Patent Publication Number: US-11638581-B2

Title: Powered surgical stapler

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application claiming priority under 35 U.S.C. § 120 to U.S. patent application Ser. No. 16/746,114 entitled POWERED SURGICAL STAPLER, filed Jan. 17, 2020, which issued on Aug. 9, 2022 as U.S. Pat. No. 11,406,381, which is a continuation application claiming priority under 35 U.S.C. § 120 to U.S. patent application Ser. No. 15/869,706, entitled SURGICAL INSTRUMENT SYSTEM, filed Jan. 12, 2018, which issued on Jul. 7, 2020 as U.S. Pat. No. 10,702,266, which is a continuation application claiming priority under 35 U.S.C. § 120 to U.S. patent application Ser. No. 14/248,587, entitled POWERED SURGICAL STAPLER, filed Apr. 9, 2014, which issued on Jan. 16, 2018 as U.S. Pat. No. 9,867,612, which claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application Ser. No. 61/812,365, entitled SURGICAL INSTRUMENT WITH MULTIPLE FUNCTIONS PERFORMED BY A SINGLE MOTOR, filed Apr. 16, 2013, of U.S. Provisional Patent Application Ser. No. 61/812,376, entitled LINEAR CUTTER WITH POWER, filed Apr. 16, 2013, of U.S. Provisional Patent Application Ser. No. 61/812,382, entitled LINEAR CUTTER WITH MOTOR AND PISTOL GRIP, filed Apr. 16, 2013, of U.S. Provisional Patent Application Ser. No. 61/812,385, entitled SURGICAL INSTRUMENT HANDLE WITH MULTIPLE ACTUATION MOTORS AND MOTOR CONTROL, filed Apr. 16, 2013, and of U.S. Provisional Patent Application Ser. No. 61/812,372, entitled SURGICAL INSTRUMENT WITH MULTIPLE FUNCTIONS PERFORMED BY A SINGLE MOTOR, filed Apr. 16, 2013, the entire disclosures of which are hereby incorporated by reference herein. 
    
    
     BACKGROUND 
     Various forms of the invention relate to surgical instruments and, in various embodiments, to surgical cutting and stapling instruments and staple cartridges therefor that are designed to cut and staple tissue. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The various features and advantages of this invention and the manner of attaining them will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG.  1    is a perspective view of a modular surgical system that includes a motor-driven surgical instrument and three interchangeable end effectors; 
         FIG.  2    is a side perspective view of the motor-driven surgical instrument with a portion of the handle housing removed for clarity; 
         FIG.  3    is a partial exploded assembly view of the surgical instrument of  FIG.  2   ; 
         FIG.  4    is another partial exploded assembly view of the surgical instrument of  FIGS.  2  and  3   ; 
         FIG.  5    is a side elevational view of the motor-driven surgical instrument with a portion of the handle housing removed; 
         FIG.  6    is a perspective view of a motor drive system and transmission assembly with the transmission assembly in the first drive position wherein actuation of the motor will result in the actuation of a first drive system of the surgical instrument of  FIGS.  2 - 5   ; 
         FIG.  6 A  is a perspective view of an alternative transmission carriage with locking means; 
         FIG.  6 B  is a perspective view of a motor drive system and transmission assembly including the transmission carriage of  FIG.  6 A  with the transmission assembly in the first drive position wherein actuation of the motor will result in the actuation of the first drive system and the second drive system is locked by the locking means; 
         FIG.  6 C  is a perspective view of the motor drive system and transmission assembly of  FIG.  6 B  with the transmission assembly in the second drive position wherein actuation of the motor will result in the actuation of the second drive system and the first drive system is locked by the locking means; 
         FIG.  7    is another perspective view of the motor drive system and transmission assembly of  FIG.  6    with the transmission assembly in the second drive position wherein actuation of the motor will result in the actuation of the second drive system; 
         FIG.  8    is a side elevational view of another motor-driven surgical instrument with a portion of the handle housing and other portions thereof omitted for clarity; 
         FIG.  9    is a perspective view of the motor, transmission assembly and first and second drive systems of the surgical instrument of  FIG.  8    with the transmission assembly thereof in the first drive position; 
         FIG.  10    is a cross-sectional elevational view of the motor, transmission assembly and first and second drive systems of  FIG.  9    with the transmission assembly in the first drive position; 
         FIG.  11    is another perspective view of the motor, transmission assembly and first and second drive systems of  FIGS.  9  and  10    with the transmission assembly in the second drive position; 
         FIG.  12    is another cross-sectional elevational view of the motor, transmission assembly and first and second drive systems of  FIGS.  9 - 11    with the transmission assembly in the second drive position; 
         FIG.  13    is a partial rear perspective view of a portion of another motor driven surgical instrument; 
         FIG.  14    is a side elevational view of the motor, transmission assembly and first and second drive systems of the surgical instrument of  FIG.  13   ; 
         FIG.  15    is a cross-sectional view of the transmission assembly of the surgical instrument of  FIGS.  13  and  14    in a first drive position; 
         FIG.  16    is another cross-sectional view of the transmission assembly of the surgical instrument of  FIGS.  13 - 15    in a second drive position; 
         FIG.  17    is a perspective view of another motor driven surgical instrument arrangement with a portion of the housing removed for clarity; 
         FIG.  18    is a perspective view of a motor, transmission assembly and first and second drive systems of the surgical instrument of  FIG.  17   ; 
         FIG.  19    is an exploded assembly view of the motor, transmission assembly and first and second drive systems of  FIG.  18   ; 
         FIG.  20    is a cross-sectional view of portions of the motor, transmission assembly and first and second drive systems of  FIGS.  18  and  19    with the transmission shaft assembly thereof in a first drive position; 
         FIG.  21    is another cross-sectional view of the portions of the motor, transmission assembly and first and second drive systems of  FIG.  20    with the transmission shaft assembly thereof in a second drive position; 
         FIG.  22    is a perspective view of another motor, transmission assembly and first and second drive systems of one form of a surgical instrument of the present invention; 
         FIG.  23    is an exploded assembly view of the motor, transmission assembly and first and second drive systems of  FIG.  22   ; 
         FIG.  24    is a cross-sectional view of the motor, transmission assembly and first and second drive systems of  FIGS.  22  and  23    with the transmission assembly in first drive position; 
         FIG.  25    is another cross-sectional view of the motor, transmission assembly and first and second drive systems of  FIGS.  22 - 24    with the transmission assembly in a second drive position; 
         FIG.  26    is another cross-sectional view of the motor and transmission assembly of  FIGS.  22 - 25    with the transmission assembly in the first drive position; 
         FIG.  27    is another cross-sectional view of the motor and transmission assembly of  FIGS.  22 - 26    with the transmission assembly in the second drive position; 
         FIG.  28    is a side elevational view of a portion of another motor driven surgical instrument with a portion of the housing omitted for clarity; 
         FIG.  29    is a perspective view of a portion of another motor driven surgical instrument with a portion of the housing omitted for clarity; 
         FIG.  30    is a front perspective view of a motor driven unit with first and second rotary drive systems; 
         FIG.  31    is a bottom perspective view of the motor driven unit of  FIG.  30   ; 
         FIG.  32    is a perspective view of the motor driven unit of  FIGS.  31  and  32    with the housing removed therefrom; 
         FIG.  33    is an exploded assembly view of a mechanical coupling system for operably coupling four rotary drive shafts together; 
         FIG.  34    is a front perspective view of a surgical end effector with a portion of the end effector housing removed for clarity; 
         FIG.  35    is another front perspective view of the surgical end effector of  FIG.  34    with portions of the closure system and lower jaw omitted for clarity; 
         FIG.  36    is an exploded perspective assembly view of the surgical end effector of  FIGS.  34  and  35   ; 
         FIG.  37    is a side elevational view of the surgical end effector of  FIGS.  33 - 36    with a portion of the housing omitted for clarity; 
         FIG.  38    is a left side perspective view of another end effector arrangement with a portion of the end effector housing omitted for clarity; 
         FIG.  39    is an exploded assembly view of the end effector of  FIG.  38   ; 
         FIG.  40    is a right side perspective view of the end effector arrangement of  FIGS.  37  and  38    with another portion of the end effector housing omitted for clarity; 
         FIG.  41    is a cross-sectional view of the surgical end effector arrangement of  FIGS.  38 - 40   ; 
         FIG.  42    is a cross-sectional perspective view of another surgical end effector; 
         FIG.  43    is a partial exploded assembly view of the surgical end effector of  FIG.  42   ; 
         FIG.  44    is another partial perspective view of a portion of the surgical end effector of  FIGS.  42  and  43   ; 
         FIG.  45    is another cross-sectional view of the surgical end effector of  FIGS.  42 - 44   ; 
         FIG.  46    is a perspective view of an end effector arrangement with a drive disengagement assembly; 
         FIG.  47    is a partial perspective view of the surgical end effector of  FIG.  46    with portions thereof omitted for clarity and with the proximal drive train portion of the closure system detached from the distal drive train portion of the closure system; 
         FIG.  48    is a partial perspective view of the surgical end effector of  FIGS.  46  and  47    with portions thereof omitted for clarity and with the distal coupler member seated within the slot in the proximal coupler member and the drive coupler pin removed therefrom; 
         FIG.  49    is another partial perspective view of the surgical end effector of  FIG.  48    showing portions of the end effector firing system; 
         FIG.  50    is a perspective view of another surgical end effector arrangement; 
         FIG.  50 A  is an enlarged view of a portion of the surgical end effector of  FIG.  50   ; 
         FIG.  51    is a perspective view of a portion of the end effector of  FIG.  50    with a portion of the housing omitted for clarity; 
         FIG.  52    is another perspective view of the end effector of  FIGS.  50  and  51    with portions of the housing and closure system omitted for clarity; 
         FIG.  53    is another perspective view of the end effector of  FIGS.  50 - 52    with portions of the closure system and a portion of the housing omitted for clarity; 
         FIG.  54    is a perspective view of another end effector that is equipped with a drive disengagement assembly; 
         FIG.  55    is a side elevational view of the end effector of  FIG.  54   ; 
         FIG.  56    is a perspective view of a portion of the end effector of  FIGS.  54  and  55    with a portion of the end effector housing omitted for clarity; 
         FIG.  57    is another perspective view of the end effector of  FIGS.  54 - 56    with the tool head thereof in a closed position; 
         FIG.  58    is a another partial perspective view of the end effector of  FIG.  57    with a portion of the end effector housing omitted for clarity; 
         FIG.  59    is another perspective view of the end effector of  FIG.  58    with the drive coupler pin removed; 
         FIG.  60    is another perspective view of the end effector of  FIG.  59    with the drive coupler pin removed and the closure drive beam assembly moved proximally to open the tool head; 
         FIG.  61    is a block diagram of a modular motor driven surgical instrument comprising a handle portion and a shaft portion; 
         FIG.  62    is a table depicting total time to complete a stroke and load current requirements for various operations of various device shafts; 
         FIGS.  63 A and  63 B  illustrate a detail diagram of the electrical system in the handle portion of the modular motor driven surgical instrument; 
         FIG.  64    is block diagram of the electrical system of the handle and shaft portions of the modular motor driven surgical instrument; 
         FIG.  65    illustrates a mechanical switching motion control system to eliminate microprocessor control of motor functions; 
         FIG.  66    is a perspective view of a coupling arrangement comprising a coupler housing and a pair of sockets positioned within the coupler housing, according to various embodiments of the present disclosure; 
         FIG.  67    is a cross-sectional, perspective view of the coupling arrangement of  FIG.  66   , depicting a pair of drive members uncoupled to the pair of sockets and further depicting the coupling arrangement in an unlocked configuration, according to various embodiments of the present disclosure; 
         FIG.  68    is a cross-sectional, perspective view of the coupling arrangement of  FIG.  66   , depicting the pair of drive members coupled to the pair of sockets and further depicting the coupling arrangement in a locked configuration, according to various embodiments of the present disclosure; 
         FIG.  69    is a cross-sectional, perspective view of the coupling arrangement of  FIG.  66   , depicting the pair of drive members coupled to the pair of sockets and further depicting the coupling arrangement in an unlocked configuration, according to various embodiments of the present disclosure; 
         FIG.  70    is a perspective view of an insert of the coupling arrangement of  FIG.  66   , according to various embodiments of the present disclosure; 
         FIG.  71    is a perspective view of a socket of the coupling arrangement of  FIG.  66   , according to various embodiments of the present disclosure; 
         FIG.  72    is a perspective view of a latch of the coupling arrangement of  FIG.  66   , according to various embodiments of the present disclosure; 
         FIG.  73    is a cross-sectional, perspective view of a surgical end effector attachment for use with a surgical instrument handle, according to various embodiments of the present disclosure; 
         FIG.  74    is an exploded, perspective view of drive systems of the surgical end effector attachment of  FIG.  73   , according to various embodiments of the present disclosure; 
         FIG.  75    is a perspective view of a handle for a surgical instrument, wherein the handle comprises a drive system having a first output drive assembly and a second output drive assembly, according to various embodiments of the present disclosure; 
         FIG.  76    is a perspective view of the drive system of  FIG.  75   , according to various embodiments of the present disclosure; 
         FIG.  77    is a cross-sectional, elevation view of the handle of  FIG.  75   , depicting the drive system engaged with the first output drive assembly and disengaged from the second output drive assembly, according to various embodiments of the present disclosure; 
         FIG.  78    is a cross-sectional, elevation view of the drive system of  FIG.  75   , depicting the drive system engaged with the second output drive assembly and disengaged from the first output drive assembly, according to various embodiments of the present disclosure; 
         FIG.  79    is a partial cross-sectional perspective view of a surgical instrument including a rotatable drive shaft, a closure drive operable by said drive shaft, and a firing drive operable by said drive shaft, wherein the closure drive is illustrated in a partially open configuration and the firing drive is illustrated in an unfired configuration; 
         FIG.  80    is a perspective view of the rotatable drive shaft of  FIG.  79   ; 
         FIG.  81    is a partial cross-sectional perspective view of the surgical instrument of  FIG.  79    illustrated with the closure drive in an open configuration and the firing drive in an unfired configuration; 
         FIG.  82    is a partial cross-sectional perspective view of the surgical instrument of  FIG.  79    illustrated with the closure drive in a closed configuration and the firing drive in an unfired configuration; 
         FIG.  83    is a partial cross-sectional perspective view of the surgical instrument of  FIG.  79    illustrated with the closure drive in a closed configuration and the firing drive in a fired configuration; 
         FIG.  84    is a partial cross-sectional perspective view of the surgical instrument of  FIG.  79    illustrated with the firing drive in a retracted configuration and the closure drive in the process of being re-opened; 
         FIG.  85    is a partial cross-sectional view of an end effector and a shaft of a surgical instrument illustrated in a closed, unfired configuration; 
         FIG.  86    is a perspective view of a transmission for operating the surgical instrument of  FIG.  85    illustrated in a configuration which corresponds with the configuration of  FIG.  85   ; 
         FIG.  87    is an exploded view of the transmission of  FIG.  86   ; 
         FIG.  88    is a partial cross-sectional view of the end effector and the shaft of  FIG.  85    illustrated in an open, unfired configuration; 
         FIG.  89    is a perspective view of the transmission of  FIG.  86    illustrated in a configuration which corresponds with the configuration illustrated in  FIG.  88   ; 
         FIG.  90    is a partial cross-sectional view of the end effector and the shaft of  FIG.  85    illustrated in a closed, unfired configuration; 
         FIG.  91    is a perspective view of the transmission of  FIG.  86    illustrated in a configuration which corresponds with the configuration illustrated in  FIG.  90   ; 
         FIG.  92    is a partial cross-sectional view of the end effector and the shaft of  FIG.  85    illustrated in a closed, fired configuration; 
         FIG.  93    is a perspective view of the transmission of  FIG.  86    illustrated in a configuration which corresponds with the configuration illustrated in  FIG.  92   ; 
         FIG.  94    is a perspective view of a surgical stapling instrument in accordance with at least one embodiment; 
         FIG.  95    is an exploded view of a handle of the surgical stapling instrument of  FIG.  94   ; 
         FIG.  96    is an exploded view of an end effector of the surgical stapling instrument of  FIG.  94   ; 
         FIG.  97    is a partial perspective view of a motor and gear assembly of the surgical stapling instrument of  FIG.  94   ; 
         FIG.  98    is a cross-sectional elevational view of the surgical stapling instrument of  FIG.  94   ; 
         FIG.  99    is a perspective view of a surgical stapling instrument in accordance with at least one embodiment illustrated in an open, unlatched condition; 
         FIG.  100    is a perspective view of the surgical stapling instrument of  FIG.  99    illustrated in a closed, unlatched condition; 
         FIG.  101    is a perspective view of the surgical stapling instrument of  FIG.  99    illustrated in a closed, latched condition; 
         FIG.  102    is a plan view of the surgical stapling instrument of  FIG.  99   ; 
         FIG.  103    is a cross-sectional view of the surgical stapling instrument of  FIG.  99   ; 
         FIG.  104    is a detail cross-sectional view of the surgical stapling instrument of  FIG.  99   ; 
         FIG.  105    is an exploded view of a firing drive of the surgical stapling instrument of  FIG.  99   ; 
         FIG.  106    is an exploded view of a closing drive of the surgical stapling instrument of  FIG.  99   ; 
         FIG.  107    is a cross-sectional view of a surgical stapling instrument in accordance with at least one embodiment comprising a handle, a shaft, and an end effector; 
         FIG.  108    is a cross-sectional view of the handle of the surgical stapling instrument of  FIG.  107    illustrated in an open configuration; 
         FIG.  109    is a cross-sectional view of the handle of the surgical stapling instrument of  FIG.  107    illustrated in a closed configuration; 
         FIG.  110    is a perspective view of the handle of the surgical stapling instrument of  FIG.  107    illustrated with some components removed; 
         FIG.  111    is a perspective view of a surgical stapling instrument in accordance with at least one embodiment comprising a handle and a shaft; 
         FIG.  112    is a perspective view of the surgical stapling instrument of  FIG.  111    illustrating the handle detached from the shaft; 
         FIG.  113    is an exploded view of the surgical stapling instrument of  FIG.  111   ; 
         FIG.  114    is a partial cross-sectional view of the handle of  FIG.  111    illustrating a transmission operably engaged with a closure system of the surgical stapling instrument of  FIG.  111   ; 
         FIG.  115    is a partial cross-sectional view of the handle of  FIG.  111    illustrating the transmission of  FIG.  114    operably engaged with a firing system of the surgical stapling instrument of  FIG.  111   ; 
         FIG.  116    is an exploded view of the transmission of  FIG.  114   ; 
         FIG.  117    is a perspective view of a surgical stapling instrument in accordance with at least one embodiment illustrated with some components removed and illustrated in an open configuration; 
         FIG.  118    is a perspective view of the surgical stapling instrument of  FIG.  117    illustrated with some components removed and illustrated in a closed configuration; 
         FIG.  119    is a perspective view of another end effector arrangement and a staple pack embodiment therefor prior to installing the staple pack into the end effector; 
         FIG.  120    is another perspective view of the end effector and staple pack of  FIG.  119    with the staple pack installed into the end effector; and 
         FIG.  121    is another perspective view of the end effector and staple pack of  FIG.  120    with the keeper member of the staple pack removed therefrom. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate preferred embodiments of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
     DETAILED DESCRIPTION 
     Applicant of the present application owns the following patent applications that were filed on Mar. 1, 2013 and which are each herein incorporated by reference in their respective entireties: 
     U.S. patent application Ser. No. 13/782,295, entitled ARTICULATABLE SURGICAL INSTRUMENTS WITH CONDUCTIVE PATHWAYS FOR SIGNAL COMMUNICATION, now U.S. Pat. No. 9,700,309; 
     U.S. patent application Ser. No. 13/782,323, entitled ROTARY POWERED ARTICULATION JOINTS FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,782,169; 
     U.S. patent application Ser. No. 13/782,338, entitled THUMBWHEEL SWITCH ARRANGEMENTS FOR SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2014/0249557; 
     U.S. patent application Ser. No. 13/782,499, entitled ELECTROMECHANICAL SURGICAL DEVICE WITH SIGNAL RELAY ARRANGEMENT, now U.S. Pat. No. 9,358,003; 
     U.S. patent application Ser. No. 13/782,460, entitled MULTIPLE PROCESSOR MOTOR CONTROL FOR MODULAR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,554,794; 
     U.S. patent application Ser. No. 13/782,358, entitled JOYSTICK SWITCH ASSEMBLIES FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,326,767; 
     U.S. patent application Ser. No. 13/782,481, entitled SENSOR STRAIGHTENED END EFFECTOR DURING REMOVAL THROUGH TROCAR, now U.S. Pat. No. 9,468,438; 
     U.S. patent application Ser. No. 13/782,518, entitled CONTROL METHODS FOR SURGICAL INSTRUMENTS WITH REMOVABLE IMPLEMENT PORTIONS, now U.S. Patent Application Publication No. 2014/0246475; 
     U.S. patent application Ser. No. 13/782,375, entitled ROTARY POWERED SURGICAL INSTRUMENTS WITH MULTIPLE DEGREES OF FREEDOM, now U.S. Pat. No. 9,398,911; and 
     U.S. patent application Ser. No. 13/782,536, entitled SURGICAL INSTRUMENT SOFT STOP, now U.S. Pat. No. 9,307,986, are hereby incorporated by reference in their entireties. 
     Applicant of the present application also owns the following patent applications that were filed on Mar. 14, 2013 and which are each herein incorporated by reference in their respective entireties: 
     U.S. patent application Ser. No. 13/803,097, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING A FIRING DRIVE, now U.S. Pat. No. 9,687,230; 
     U.S. patent application Ser. No. 13/803,193, entitled CONTROL ARRANGEMENTS FOR A DRIVE MEMBER OF A SURGICAL INSTRUMENT, now U.S. Pat. No. 9,332,987; 
     U.S. patent application Ser. No. 13/803,053, entitled INTERCHANGEABLE SHAFT ASSEMBLIES FOR USE WITH A SURGICAL INSTRUMENT, now U.S. Pat. No. 9,883,860; 
     U.S. patent application Ser. No. 13/803,086, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. Patent Application Publication No. 2014/0263541; 
     U.S. patent application Ser. No. 13/803,210, entitled SENSOR ARRANGEMENTS FOR ABSOLUTE POSITIONING SYSTEM FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,808,244; 
     U.S. patent application Ser. No. 13/803,148, entitled MULTI-FUNCTION MOTOR FOR A SURGICAL INSTRUMENT, now U.S. Pat. No. 10,470,762; 
     U.S. patent application Ser. No. 13/803,066, entitled DRIVE SYSTEM LOCKOUT ARRANGEMENTS FOR MODULAR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,629,623; 
     U.S. patent application Ser. No. 13/803,117, entitled ARTICULATION CONTROL SYSTEM FOR ARTICULATABLE SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,351,726; 
     U.S. patent application Ser. No. 13/803,130, entitled DRIVE TRAIN CONTROL ARRANGEMENTS FOR MODULAR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,351,727; and 
     U.S. patent application Ser. No. 13/803,159, entitled METHOD AND SYSTEM FOR OPERATING A SURGICAL INSTRUMENT, now U.S. Pat. No. 9,888,919. 
     Applicant of the present application also owns the following patent applications that were filed on Mar. 25, 2014 and are each herein incorporated by reference in their respective entireties: 
     U.S. patent application Ser. No. 14/226,106, entitled POWER MANAGEMENT CONTROL SYSTEMS FOR SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2015/0272582; 
     U.S. patent application Ser. No. 14/226,099, entitled STERILIZATION VERIFICATION CIRCUIT, now U.S. Pat. No. 9,826,977; 
     U.S. patent application Ser. No. 14/226,094, entitled VERIFICATION OF NUMBER OF BATTERY EXCHANGES/PROCEDURE COUNT, now U.S. Patent Application Publication No. 2015/0272580; 
     U.S. patent application Ser. No. 14/226,117, entitled POWER MANAGEMENT THROUGH SLEEP OPTIONS OF SEGMENTED CIRCUIT AND WAKE UP CONTROL, now U.S. Pat. No. 10,013,049; 
     U.S. patent application Ser. No. 14/226,075, entitled MODULAR POWERED SURGICAL INSTRUMENT WITH DETACHABLE SHAFT ASSEMBLIES, now U.S. Pat. No. 9,743,929; 
     U.S. patent application Ser. No. 14/226,093, entitled FEEDBACK ALGORITHMS FOR MANUAL BAILOUT SYSTEMS FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,028,761; 
     U.S. patent application Ser. No. 14/226,116, entitled SURGICAL INSTRUMENT UTILIZING SENSOR ADAPTATION, now U.S. Patent Application Publication No. 2015/0272571; 
     U.S. patent application Ser. No. 14/226,071, entitled SURGICAL INSTRUMENT CONTROL CIRCUIT HAVING A SAFETY PROCESSOR, now U.S. Pat. No. 9,690,362; 
     U.S. patent application Ser. No. 14/226,097, entitled SURGICAL INSTRUMENT COMPRISING INTERACTIVE SYSTEMS, now U.S. Pat. No. 9,820,738; 
     U.S. patent application Ser. No. 14/226,126, entitled INTERFACE SYSTEMS FOR USE WITH SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,004,497; 
     U.S. patent application Ser. No. 14/226,133, entitled MODULAR SURGICAL INSTRUMENT SYSTEM, now U.S. Patent Application Publication No. 2015/0272557; 
     U.S. patent application Ser. No. 14/226,081, entitled SYSTEMS AND METHODS FOR CONTROLLING A SEGMENTED CIRCUIT, now U.S. Pat. No. 9,804,618; 
     U.S. patent application Ser. No. 14/226,076, entitled POWER MANAGEMENT THROUGH SEGMENTED CIRCUIT AND VARIABLE VOLTAGE PROTECTION, now U.S. Pat. No. 9,733,663; 
     U.S. patent application Ser. No. 14/226,111, entitled SURGICAL STAPLING INSTRUMENT SYSTEM, now U.S. Pat. No. 9,750,499; and 
     U.S. patent application Ser. No. 14/226,125, entitled SURGICAL INSTRUMENT COMPRISING A ROTATABLE SHAFT, now U.S. Pat. No. 10,201,364. 
     Applicant of the present application also owns the following patent applications that were filed on Apr. 9, 2014 and which are each herein incorporated by reference in their respective entireties: 
     U.S. patent application Ser. No. 14/248,590, entitled MOTOR DRIVEN SURGICAL INSTRUMENTS WITH LOCKABLE DUAL DRIVE SHAFTS, now U.S. Pat. No. 9,826,976; 
     U.S. patent application Ser. No. 14/248,581, entitled SURGICAL INSTRUMENT COMPRISING A CLOSING DRIVE AND A FIRING DRIVE OPERATED FROM THE SAME ROTATABLE OUTPUT, now U.S. Pat. No. 9,649,110; 
     U.S. patent application Ser. No. 14/248,595, entitled SURGICAL INSTRUMENT SHAFT INCLUDING SWITCHES FOR CONTROLLING THE OPERATION OF THE SURGICAL INSTRUMENT, now U.S. Pat. No. 9,844,368; 
     U.S. patent application Ser. No. 14/248,588, entitled POWERED LINEAR SURGICAL STAPLER, now U.S. Pat. No. 10,405,857; 
     U.S. patent application Ser. No. 14/248,591, entitled TRANSMISSION ARRANGEMENT FOR A SURGICAL INSTRUMENT, now U.S. Pat. No. 10,149,680; 
     U.S. patent application Ser. No. 14/248,584, entitled MODULAR MOTOR DRIVEN SURGICAL INSTRUMENTS WITH ALIGNMENT FEATURES FOR ALIGNING ROTARY DRIVE SHAFTS WITH SURGICAL END EFFECTOR SHAFTS, now U.S. Pat. No. 9,801,626; 
     U.S. patent application Ser. No. 14/248,586, entitled DRIVE SYSTEM DECOUPLING ARRANGEMENT FOR A SURGICAL INSTRUMENT, now U.S. Pat. No. 10,136,887; and 
     U.S. patent application Ser. No. 14/248,607, entitled MODULAR MOTOR DRIVEN SURGICAL INSTRUMENTS WITH STATUS INDICATION ARRANGEMENTS, now U.S. Pat. No. 9,814,460. 
     Certain exemplary embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the devices and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those of ordinary skill in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the various embodiments of the present invention is defined solely by the claims. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention. 
     Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment”, or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment”, or “in an embodiment”, or the like, in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Thus, the particular features, structures, or characteristics illustrated or described in connection with one embodiment may be combined, in whole or in part, with the features structures, or characteristics of one or more other embodiments without limitation. Such modifications and variations are intended to be included within the scope of the present invention. 
     The terms “proximal” and “distal” are used herein with reference to a clinician manipulating the handle portion of the surgical instrument. The term “proximal” referring to the portion closest to the clinician and the term “distal” referring to the portion located away from the clinician. It will be further appreciated that, for convenience and clarity, spatial terms such as “vertical”, “horizontal”, “up”, and “down” may be used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and/or absolute. 
     Various exemplary devices and methods are provided for performing laparoscopic and minimally invasive surgical procedures. However, the person of ordinary skill in the art will readily appreciate that the various methods and devices disclosed herein can be used in numerous surgical procedures and applications including, for example, in connection with open surgical procedures. As the present Detailed Description proceeds, those of ordinary skill in the art will further appreciate that the various instruments disclosed herein can be inserted into a body in any way, such as through a natural orifice, through an incision or puncture hole formed in tissue, etc. The working portions or end effector portions of the instruments can be inserted directly into a patient&#39;s body or can be inserted through an access device that has a working channel through which the end effector and elongated shaft of a surgical instrument can be advanced. 
     Turning to the Drawings wherein like numerals denote like components throughout the several views,  FIG.  1    depicts a modular surgical instrument system generally designated as  2  that, in one form, includes a motor driven surgical instrument  10  that may be used in connection with a variety of surgical end effectors such as, for example, end effectors  1000 ,  2000  and  3000 . In the illustrated embodiment, the motor driven surgical instrument  10  includes a housing  12  that consists of a handle  14  that is configured to be grasped, manipulated and actuated by a clinician. As the present Detailed Description proceeds, it will be understood that the various unique and novel drive system arrangements depicted in connection with handle  14  as well as the various end effector arrangements disclosed herein may also be effectively employed in connection with robotically-controlled surgical systems. Thus, the term “housing” may also encompass a housing or similar portion of a robotic system that may house or otherwise operably support various forms of the drive systems depicted herein and which may be configured to generate control motions which could be used to actuate the end effector arrangements described herein and their respective equivalent structures. The term “frame” may refer to a portion of a handheld surgical instrument. The term “frame” may also represent a portion of a motor driven system or a robotically controlled surgical instrument and/or a portion of the robotic system that may be used to operably control a surgical instrument. For example, the drive system arrangements and end effector arrangements disclosed herein may be employed with various robotic systems, instruments, components and methods disclosed in U.S. patent application Ser. No. 13/118,241, entitled SURGICAL STAPLING INSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENT ARRANGEMENTS, now U.S. Pat. No. 9,072,535, which is hereby incorporated by reference herein in its entirety. 
     Referring now to  FIGS.  2 - 5   , the handle  14  may comprise a pair of handle housing segments  16  and  18  that may be interconnected by screws, snap features, adhesive, etc. In the illustrated arrangement, the handle housing segments  16 ,  18  cooperate to form a pistol grip portion  19  that can be gripped and manipulated by the clinician. As will be discussed in further detail below, the handle  14  operably supports two rotary drive systems  20 ,  40  therein that are configured to generate and apply various control motions to corresponding drive shaft portions of a particular end effector coupled thereto. The first rotary drive system  20  may, for example, be employed to apply “closure” motions to a corresponding closure drive shaft arrangement that is operably supported in an end effector and the second rotary drive system  40  may be employed to apply “firing” motions to a corresponding firing drive shaft arrangement in the end effector that is coupled thereto. 
     The first and second rotary drive systems  20 ,  40  are powered by a motor  80  through a unique and novel “shiftable” transmission assembly  60  that essentially shifts power/motion between two power trains. The first rotary drive system  20  includes a first rotary drive shaft  22  that is rotatably supported in the housing  12  of the handle  14  and defines a first drive shaft axis “FDA-FDA”. A first drive gear  24  is keyed onto or otherwise non-rotatably affixed to the first rotary drive shaft  22  for rotation therewith about the first drive shaft axis FDA-FDA. Similarly, the second rotary drive system  40  includes a second rotary drive shaft  42  that is rotatably supported in the housing  12  of the handle  14  and defines a second drive shaft axis “SDA-SDA”. In at least one arrangement, the second drive shaft axis SDA-SDA is offset from and parallel or is substantially parallel to the first drive shaft axis FDA-FDA. As used in this context, the term “offset” means that the first and second drive shaft axes are not coaxial for example. The second rotary drive shaft  42  has a second drive gear  44  keyed onto or otherwise non-rotatably affixed to the second drive shaft  42  for rotation therewith about the second drive shaft axis SDA-SDA. In addition, the second drive shaft  42  has an intermediate drive gear  46  rotatably journaled thereon such that the intermediate drive gear  46  is freely rotatable on the second rotary drive shaft  42  about the second drive shaft axis SDA-SDA. 
     Referring to  FIGS.  2 - 5   , in one form, the motor  80  includes a motor output shaft  81  that has a motor drive gear  82  non-rotatably attached thereto. The motor drive gear  82  is configured for intermeshing “operable” engagement with the transmission assembly  60  as will be discussed in further detail below. In at least one form, the transmission assembly  60  includes a transmission carriage  62  that is supported for axial travel between the drive gear  82  and gears  44  and  46  on the second rotary drive shaft  42 . For example, the transmission carriage  62  may be slidably journaled on a support shaft  63  that is mounted within the housing  12  on a shaft mount  61  such that the line of action of the transmission carriage is perpendicular to the gear trains of the rotary drive systems. The shaft mount  61  is configured to be rigidly supported within slots or other features within the housing  10 . The transmission carriage  62  includes a carriage gear  64  that is rotatably supported on the support shaft  63  and is configured for selective meshing engagement with gears  44  and  46  while in driving engagement with drive gear  82 . In the arrangement depicted in  FIGS.  2 - 5   , the transmission carriage  62  is operably attached to a shifter or a “means for shifting”  70  that is configured to axially shift the transmission carriage  62  between a “first drive position” and a “second drive position”. In one form, for example, the means for shifting  70  includes a shifter solenoid  71  that is supported within the housing  12  of the handle  14 . The shifter solenoid  71  may comprise a bi-stable solenoid or, for example, may comprise a “dual position, spring loaded” solenoid. The illustrated arrangement, for example, includes a spring  72  that biases the transmission carriage  62  in the distal direction “DD” to the first drive position wherein the carriage gear  64  is in meshing engagement with the intermediate drive gear  46  while also in meshing engagement with the drive gear  82 . When in that first drive position, activation of the motor  80  will result in rotation of gears  82 ,  46  and  24  which will ultimately result in rotation of the first drive shaft  22 . As will be further discussed herein, the shifter solenoid  71  may be actuated by a firing trigger  90  that is pivotally supported on the housing  12  of handle  14  as shown in  FIGS.  2  and  5   . In the illustrated embodiment, the firing trigger  90  is pivotally supported on a firing trigger shaft  92  mounted in the handle  14 . The firing trigger  90  is normally biased in an unactuated position by a firing trigger spring  94 . See  FIG.  3   . The firing trigger  90  is mounted for operable actuation of a firing switch  96  that is operably supported on a control circuit board assembly  100 . In the illustrated arrangement, actuation of the firing trigger  90  results in the actuation of the shifter solenoid  71 . As described in more detail hereinbelow in connection with  FIGS.  61 ,  63 A,  63 B,  64   , the handle processor  7024  provides the drive signal to shifter solenoid  7032  ( 71 ). With reference now back to  FIGS.  2 - 5   , thus, actuation of the firing trigger  90  will result in the shifter solenoid  71  pulling the transmission carriage  62  in the proximal direction “PD” to thereby move the carriage gear  64  into meshing engagement with the second drive gear  44 . See  FIG.  7   . Actuation of motor  80  when the carriage gear  64  is in meshing engagement with the drive gear  82  and the second drive gear  44  will result in the rotation of the second drive shaft  42  about the second drive shaft axis “SDA”. As can also be seen in  FIGS.  2 - 5   , the shiftable transmission assembly  60  may also include an indicator system  74  that includes a pair of switches  75  and  76  that are operably coupled to the control board  100  as well as a transmission indicator light  77 . The switches  75 ,  76  serve to detect the position of the transmission carriage  62  which results in the control system actuating the indicator light  77  depending upon the position of the transmission carriage  62 . For example, the indicator light  77  may be energized when the transmission carriage  62  is in the first drive position. This provides the clinician with an indication that actuation of the motor  80  will result in the actuation of the first drive system  20 . 
     Various surgical instruments disclosed herein may also include a transmission assembly  60 ′ that is substantially identical to transmission assembly  60 , but also include a locking assembly or means (generally designated as  65 ) for locking the first and second drive systems  20 ,  40  to prevent their inadvertent actuation when they are not intended to be actuated. For example,  FIG.  6 A  illustrates an alternative transmission carriage  62 ′ that includes a first drive lock  66  and a second drive lock  68 . The first drive lock  66  comprises a first gear engagement member or tooth on the transmission carriage  62 ′ that is located for intermeshing engagement with the second drive gear  44  when the carriage gear  64  is in driving engagement with the intermediate gear  46  (i.e., when the transmission assembly  60 ′ is in the first drive position). See  FIG.  6 B . Thus, when the transmission assembly  60 ′ is in the first drive position, the first drive lock  66  is in meshing engagement with the second drive gear  44  and prevents relative rotation thereof while the first drive shaft  22  is rotated in the above-described manner. Likewise, when the transmission assembly  60 ′ is in the second drive position (i.e., the carriage gear  64  is in meshing engagement with the second drive gear  44 ), the second drive lock  68  is in meshing engagement with the intermediate drive gear  46 . See  FIG.  6 C . Thus, when the transmission assembly  60 ′ is in the second drive position, the second drive lock  68  prevents the intermediate gear  46  from rotating which also prevents the first drive gear  24  from rotating. As such, when the clinician operates the motor  80  to actuate the first drive system  20 , the second drive system  40  is locked in position. Likewise, when the clinician actuates the second drive system  40 , the first drive system  20  is locked in position. 
     The control system for the motor  80 , as described hereinbelow in connection with  FIGS.  61 ,  63 A,  63 B,  64   , may be programmed in such a way that it always stops in an orientation when one tooth of gears  42 ,  44  remains vertical or other defined position depending upon the orientation of the other matching gear. This feature will serve to avoid any interference between the gear teeth while shifting. When shifting, the locking members also shift and locks the position of the non-rotating gear train. When employed in connection with an end effector that includes a cartridge/anvil arrangement or other clamping configuration, another advantage gained by locking the non-rotating (i.e., non-powered) gear train is the retention of the clamp/anvil in a stable position while firing. 
     The motor  80  may be a DC brushed driving motor having a maximum rotation of, approximately, 25,000 RPM, for example. In other arrangements, the motor may include a brushless motor, a cordless motor, a synchronous motor, a stepper motor, or any other suitable electric motor, including motors which can be autoclavable. The motor  80  may be powered by a power source  84  that in one form may comprise a power pack  86  that is removably stored in the handle  14 . As can be seen in  FIGS.  2 - 5   , for example, the power pack  86  may be removably housed within the pistol grip portion  19  of the handle  14 . To access the power pack  86 , the clinician removes a removable cap  17  that is attached to the pistol grip portion  19  as shown. The power pack  86  may operably support a plurality of batteries (not shown) therein. The batteries may each comprise, for example, a Lithium Ion (“LI”) or other suitable battery. The power pack  86  is configured for removable operable attachment to the control circuit board assembly  100  which is also operably coupled to the motor  80  and mounted within the handle  14 . A number of batteries may be connected in series may be used as the power source for the surgical instrument. In addition, the power source  84  may be replaceable and/or rechargeable and, in at least one instance, can include CR123 batteries, for example. The motor  80  may be actuated by a “rocker-trigger”  110  that is pivotally mounted to the pistol grip portion  19  of the handle  14 . The rocker trigger  110  is configured to actuate a first motor switch  112  that is operably coupled to the control board  100 . The first motor switch  112  may comprise a pressure switch which is actuated by pivoting the rocker trigger  110  into contact therewith. Actuation of the first motor switch  112  will result in actuation of the motor  80  such that the drive gear  82  rotates in a first rotary direction. A second motor switch  114  is also attached to the circuit board  100  and mounted for selective contact by the rocker trigger  110 . Actuation of the second motor switch  114  will result in actuation of the motor  80  such that the drive gear  82  is rotated in a second direction. For example, in use, a voltage polarity provided by the power source  84  can operate the electric motor  80  in a clockwise direction wherein the voltage polarity applied to the electric motor by the battery can be reversed in order to operate the electric motor  80  in a counter-clockwise direction. As with the other forms described herein, the handle  14  can also include a sensor that is configured to detect the directions in which the drive systems are being moved. One particular implementation of the motor  80  is described hereinbelow in connection with  FIGS.  61 ,  63 A,  63 B,  64    where a brushless DC motor  7038  is described. DC motor  7038  can be autoclavable. 
       FIGS.  8 - 12    illustrate another form of surgical instrument  10 ′ that may be identical to surgical instrument  10  except for the differences noted below. Those components of surgical instrument  10 ′ that are the same as the components in the surgical instrument  10  described above will be designated with the same element numbers. Those components of surgical instrument  10 ′ that may be similar in operation, but not identical to corresponding components of surgical instrument  10 , will be designated with the same component numbers along with a “′” or in some cases a “″”. As can be seen in  FIG.  8   , for example, the first drive shaft axis “FDA” is offset from and parallel with or is substantially parallel with the second drive shaft axis “SDA”. Referring primarily to  FIG.  9   , for example, the transmission assembly  60  and, more specifically, the transmission carriage  62 ″ is manually shiftable by a linkage assembly  120  that is operably attached to the firing trigger  90 ′. As can be seen in that Figure, for example, the linkage assembly  120  includes a first transmission link  122  that is pivotally coupled to the firing trigger  90 ′ and extends axially to be pivotally coupled to a transmission yoke  124 . The transmission yoke  124  is movably pinned to the transmission carriage  62 ″. Thus, actuation of the firing trigger  90 ′ results in the axial movement of the transmission carriage  62 ″. It will therefore be understood that the linkage assembly  120  essentially performs similar actuation motions to those performed by the shifter solenoid  71  that was described above. As used in the context of this embodiment with respect to movement of the transmission carriage  62 ″, the term “manually shiftable” refers to moving the transmission carriage between the first and second drive positions without the use of electricity or other power means other than depressing the firing trigger  90 ′. 
     As can also be seen in  FIGS.  8 - 12   , the second drive gear  44 ′ is spaced apart from the intermediate gear  46 ′ on the second drive shaft  42 ′ by a spacer  45 . The second drive gear  44 ′ is keyed onto or otherwise non-rotatably affixed to the second drive shaft  42 ′, while the intermediate drive gear  46 ′ is rotatably journaled on the second drive shaft  42 ′ for free rotation relative thereto. In one form, for example, a distal drive gear  130  is supported in meshing engagement with the intermediate drive gear  46 ′. Similarly, a proximal drive gear  136  is supported in meshing engagement with the second drive gear  44 ′. In this arrangement, however, the transmission carriage  62 ″ also includes a centrally-disposed, transmission gear assembly  140  that is operably attached to the transmission carriage  62 ′ for axial travel therewith. Still referring to  FIGS.  8 - 12   , the transmission gear assembly  140  includes a centrally-disposed shifter drive gear  142  that is in slidable meshing engagement with the motor drive gear  82 . Thus, rotation of motor drive gear  82  results in rotation of the shifter drive gear  142 . In addition, a proximally extending, conically-shaped drive gear  144  is coupled to the shifter drive gear  142  and is configured for selective meshing engagement with a proximal gear socket  146  that is attached to the proximal drive gear  136 . Likewise a distally extending, conically shaped drive gear  148  is configured for selective meshing engagement with a distal gear socket  150  attached to the distal drive gear  130 . 
     When the clinician desires to actuate the first drive system  20 , the clinician moves the firing trigger  90 ′ to axially move the transmission gear assembly  140  to bring the distally extending conically-shaped drive gear  148  into seated meshing engagement with the distal gear socket  150  that is attached to distal drive gear  130 . See  FIGS.  8 - 10   . When in that position, operation of motor  80  will result in the rotation of motor drive gear  82 , shifter drive gear  142 , distal drive gear  130 , intermediate drive gear  46 ′, the first drive gear  24  and the first drive shaft  22 . When the clinician desires to actuate the second drive system  40 , the clinician moves the firing trigger  90 ′ to the position shown in  FIGS.  11  and  12    to thereby bring the proximally extending conically-shaped drive gear  144  into seated meshing engagement with the proximal gear socket  146  that is attached to the proximal drive gear  136 . When in that position, operation of motor  80  will result in the rotation of drive gear  82 , shifter drive gear  142 , proximal drive gear  136 , the second drive gear  44 ′ and the second drive shaft  42 ′. As can also be seen in  FIGS.  8 - 12   , sensors  152  and  154  may be employed to detect the position of the transmission carriage  62 ″ as will be discussed in further detail below. For example, the sensors  152  and  154  may be implemented using the Hall effect sensors  7028  described hereinbelow in connection with  FIGS.  61 ,  63 A,  63 B,  64   . 
       FIGS.  13 - 16    illustrate another form of motor driven surgical instrument  310  that may be identical to surgical instrument  10  except for the differences noted below. Those components of surgical instrument  310  that are the same as the components in the surgical instrument  10  described above will be designated with the same element numbers. In this arrangement, the first and second drive systems  20 ,  40  are powered by motor  80  through a unique and novel “shiftable” transmission assembly  360 . The first drive system  20  includes a first drive shaft  22  that has a first drive pulley  324  keyed thereon or otherwise non-rotatably affixed thereto. Similarly, the second drive system  40  includes a second drive shaft  42  that has a second drive pulley  344  keyed thereon or otherwise non-rotatably thereto. As can be seen in  FIG.  14   , for example, the first drive shaft axis “FDA” is offset from and parallel with or is substantially parallel with the second drive shaft axis “SDA”. 
     Still referring to  FIGS.  13 - 16   , in one form, the motor  80  includes a first motor pulley  382  that is non-rotatably attached to the shaft of the motor  80 . The first motor pulley  382  drives a first drive belt  385  that is received on the first drive pulley  324 . In addition, a second motor pulley  384  is non-rotatably mounted to the motor shaft and operably supports a second drive belt  387  thereon. The second drive belt  387  is also received on the second drive pulley  344  on the second drive shaft  42 . The first and second drive belts  385 ,  387  may comprise V-belts, for example. 
     The instrument  310  also includes a transmission assembly  360  that includes a transmission carriage  362  that is supported for axial travel within the instrument housing. The transmission carriage  362  operably interacts with an idler carriage  374  that is supported to move laterally in response to contact with transmission carriage  362  as the transmission carriage  362  is moved axially by the shifter solenoid  71 . The idler carriage  374  includes a first idler pulley  375  and a second idler pulley  376  mounted thereon. In the illustrated arrangement, the spring  72  biases the transmission carriage  362  in the distal direction “DD” to a first drive position wherein the transmission carriage  362  causes the idler carriage  374  to move in a first lateral direction “FLD” which causes the first idler pulley  375  to remove the slack from the first drive belt  385 . When in that position, the second idler pulley  376  is located out of engagement with the second drive belt  387 . Thus, operation of motor  80  will result in the rotation of the first drive shaft  22 . Although the second motor pulley  384  will also be rotated when the motor  80  is activated, the slack in the second drive belt  387  prevents that rotary motion from being transferred to the second drive pulley  344 . Thus, no rotary motion is transferred to the second drive system  40 . As discussed above, the shifter solenoid  71  may be actuated by the firing trigger  90 . However, in alternative arrangements, the shifter solenoid  71  may also be replaced by a manually actuatable linkage assembly of the type described above, for example. In the illustrated arrangement, actuation of the firing trigger  90  will result in the shifter solenoid  71  pulling the transmission carriage  362  in the proximal direction “PD” to thereby laterally displace the idler carriage  374  in a second lateral direction “SLD” to bring the second idler  376  into contact with the second drive belt  387  to remove the slack therefrom. Such lateral movement of the idler carriage  374  also moves the first idler  375  out of engagement with the first drive belt  385  to permit the first drive belt  385  to slacken. Thus, when in such second drive position, actuation of the motor  80  results in the actuation of the second drive system  40 . The slack in the first drive belt  385  prevents the rotary motion from being transferred to the first drive system  20 . 
     The transmission assembly  360  may provide several distinct advantages. For example, the use of V-belts eliminates meshing gears or gear alignments with a clutch. Furthermore, such transmission arrangement may be activated or deactivated under load. In addition, the transmission assembly  360  requires little displacement to disengage and engage. 
       FIGS.  17 - 21    illustrate another form of motor driven surgical instrument  410  that may be identical to surgical instrument  10  except for the differences noted below. Those components of surgical instrument  410  that are the same as the components in the surgical instrument  10  described above will be designated with the same element numbers. In this arrangement, the first and second drive systems  20 ,  40  are powered by motor  480  through a unique and novel “shiftable” transmission assembly  460 . The first drive system  20  includes a first drive shaft  22  that has a first drive pulley  424  keyed thereon or otherwise non-rotatably affixed thereto. Similarly, the second drive system  40  includes a second drive shaft  42  that has a second drive pulley  444  keyed thereon or otherwise non-rotatably fixed thereto. As can be seen in  FIG.  18   , for example, the first drive shaft axis “FDA” is offset from and parallel with or is substantially parallel with the second drive shaft axis “SDA”. 
     Referring now to  FIG.  19   , in one form, the motor  480  includes a splined drive shaft  481  that is adapted to slidably engage a transmission shaft assembly  490  that is configured to interact with a transmission carriage  462  such that axial movement of the transmission carriage  462  results in axial movement of the transmission shaft assembly  490  on the splined drive shaft  481 . As can be seen in  FIG.  19   , the transmission shaft assembly  490  has a splined bore  491  therein for slidably and operably receiving the splined drive shaft  481  therein. In addition, a distal engagement collar  492  is formed on a distal end of the transmission shaft assembly  490 . The distal engagement collar  492  is configured with an annular groove  493  that is configured to receive therein two opposed yoke rods  465  that are attached to a yoke portion  464  of the transmission carriage  462 . Such arrangement serves to couple the transmission carriage  462  to the transmission shaft assembly  490  while permitting the transmission shaft assembly  490  to rotate relative to the transmission carriage  462 . 
     Still referring to  FIG.  19   , a first motor pulley  482  is configured for selective driving engagement with the transmission shaft assembly  490 . As can be seen in  FIG.  19   , for example, the transmission shaft assembly  490  has a bearing collar  494  formed on the proximal end thereof that is sized to be slidably and rotatably received within bore  483  in the first motor pulley  482 . In addition, the first motor pulley  482  also includes a star-shaped proximal drive cavity  488  that is adapted to meshingly engage a complementary-shaped drive portion  495  formed on the transmission shaft assembly  490 . The first motor pulley  482  drives a first drive belt  485  that is also received on the first drive pulley  424 . The surgical instrument  410  also includes a second motor pulley  484  that has a star-shaped bore  489  that is configured to meshingly engage the drive portion  495  of the transmission shaft assembly  490  therein. A second motor pulley  484  operably supports a second drive belt  487  thereon that is also received on the second drive pulley  444 . 
     As indicated above, the instrument  410  also includes a transmission assembly  460  that includes a transmission carriage  462  that is supported for axial travel within the instrument housing. The transmission carriage  462  operably interacts with transmission shaft assembly  490  to also move the transmission shaft assembly  490  axially while the transmission shaft assembly  490  remains engaged with the motor shaft  481 .  FIG.  20    illustrates the shifter solenoid  71  in the unactuated position. As can be seen in that Figure, the transmission carriage  462  has moved the transmission shaft assembly  490  to its proximal-most position which may also be referred to as the “first drive position” wherein the drive portion  495  is in driving engagement with the star-shaped bore  488  in the first motor pulley  482 . Thus, rotation of the motor shaft  481  will result in rotation of the transmission shaft assembly  490  and the first motor pulley  482 . Rotation of the first motor pulley  482  results in rotation of the first drive belt  485  which ultimately results in rotation of the first drive shaft  22 . When the transmission shaft assembly  490  is in the first drive position, the transmission shaft assembly  490  rotates freely relative to the second motor pulley  484 . Thus, when the first drive system  20  is actuated, the second drive system  40  remains unactuated. When the shifter solenoid  71  is actuated to the position shown in  FIG.  21    (by actuating the firing trigger  90 ), the transmission carriage  462  moves the transmission shaft assembly  490  to its distal-most position on the motor shaft  481  which may also be referred to as the ‘second drive position”. As can be seen in  FIG.  21   , when the transmission shaft assembly  490  is in the second drive position, the drive portion  495  thereof is moved into meshing engagement with the star-shaped bore  489  in the second motor pulley  484 . Thus, rotation of the motor shaft  481  will result in the rotation of the second motor pulley  484 . Rotation of the second motor pulley  484  will result in the rotation of the second drive belt  487  which results in the rotation of the second drive shaft  42 . When in that second drive position, the transmission shaft assembly  490  rotates freely within the first motor pulley  482 . Thus, when the second drive system  40  is actuated, the first drive system  20  is in an unactuated state. 
       FIGS.  22 - 27    illustrate another motor, transmission assembly and first and second drive systems that may be employed with various surgical instruments described herein. The illustrated arrangement includes a motor  580  that has a motor shaft  581 . See  FIGS.  23  and  24   . A motor drive gear  582  or “sun gear”  582  is non-rotatably affixed to the motor shaft  581  for rotation therewith. The arrangement further includes a planetary gear assembly  570  that includes three planetary gears  572  that are rotatably supported between a distal carrier bracket  573  and proximal carrier bracket  574 . The proximal carrier bracket  574  is supported on a hub portion of the sun gear  582  such that the sun gear  582  may rotate relative to the proximal carrier bracket  574 . The distal carrier bracket  573  is affixed to a second drive shaft  542  of a second drive system  40  such that rotation of the distal carrier bracket  573  will result in the rotation of the second drive shaft  542  of the second drive system  40 . The three planetary gears  572  are supported in meshing engagement with a ring gear assembly  575 . More specifically, the planetary gears  572  are in meshing engagement with an internal ring gear  576  on the ring gear assembly  575 . The ring gear assembly  575  further includes an external ring gear  577  that is in meshing engagement with a first drive gear  524  that is affixed to a first drive shaft  522  of the first drive system  20 . As can be seen in  FIG.  24   , for example, the first drive shaft axis “FDA” is offset from and parallel with or is substantially parallel with the second drive shaft axis “SDA”. 
     As can be seen in  FIG.  23   , the arrangement further includes a solenoid  71  that may be operated by the firing trigger in the various manners described herein. In this arrangement, the transmission assembly  560  is attached to the shaft  73  of the solenoid  71 .  FIG.  24    illustrates the transmission assembly  560  in the first drive position. In one form, the transmission assembly  560  includes a locking assembly, generally designated as  590  that comprises a first or proximal lock lug portion  592  and a second or distal lock lug portion  594  on the transmission assembly  560 . As can be seen in that Figure, the transmission assembly  560  is positioned such that the proximal lock lug portion  592  is in engagement with the proximal carrier bracket  574 . When in that first drive position, the proximal lock lug portion  592  prevents the planetary gear assembly  570  from rotating as a unit with the sun gear  582 . However, rotation of the sun gear  582  results in rotation of the planetary gears  572 . Rotation of the planetary gears  572  results in rotation of the ring gear assembly  575 . Rotation of the ring gear assembly  575  results in rotation of the first drive gear  524  and the first drive shaft  522 . Because the proximal carrier bracket  574  is prevented from rotating, the distal carrier bracket  573  is also prevented from rotating. Thus, the second drive shaft  544  is also prevented from rotating while the first drive shaft  522  is rotated. A spring (not shown) may be employed to bias the solenoid  71  (and the transmission assembly  560  attached thereto) into this “first drive position”. When the clinician desires to actuate the second drive system  40 , the solenoid  71  may be actuated using the firing trigger as described above to move the solenoid shaft  73  to the position shown in  FIG.  25   . When the transmission assembly  560  is in that “second drive position”, the distal lock lug portion  594  retainingly engages the ring gear assembly  575  to prevent rotation thereof. Thus, when the sun gear  582  is rotated, the planetary gear carrier (i.e., the distal carrier bracket  573  and proximal carrier bracket  574 ) will also rotate. The planetary gears  572  will rotate within the fixed internal ring gear  576 . Such rotary motion will be transferred to the second drive shaft  542  while the first drive shaft  522  remains unactuated. 
       FIG.  28    illustrates another form of motor driven surgical instrument  610  that may be identical to surgical instrument  10  except for the differences noted below. Those components of surgical instrument  610  that are the same as the components in the surgical instrument  10  described above will be designated with the same element numbers. As can be seen in  FIG.  28   , for example, the first drive shaft axis “FDA” is offset from and parallel with or is substantially parallel with the second drive shaft axis “SDA”. This arrangement comprises a motor  680  that has dual, independently actuatable motor shafts  681 ,  683 . The motor  680  may be controlled by a firing trigger arrangement of the various types described herein, such that actuation of the firing trigger in one manner causes the motor  680  to rotate the first motor shaft  681  and actuation of the firing trigger in another manner causes the motor  680  to rotate the second motor shaft  683 . In this arrangement, a first motor gear  682  is mounted on the first motor shaft  681  and is supported in meshing engagement with an idler gear  646 . Idler gear  646  is operably supported in meshing engagement with a first drive gear  624  that is mounted to a first drive shaft  622  of a first drive system  620 . Thus, actuation of the first motor shaft  681  will result in actuation of the first drive system  620 . Likewise, a second motor gear  684  is mounted on the second motor shaft  683  and is supported in meshing engagement with a second drive gear  644  that is mounted on a second drive shaft  642  of a second drive system  640 . As such, actuation of the second motor shaft  683  will result in the actuation of the second drive system  640 . 
       FIG.  29    illustrates another form of motor driven surgical instrument  710  that may be identical to surgical instrument  10  except for the differences noted below. Those components of surgical instrument  710  that are the same as the components in the surgical instrument  10  described above will be designated with the same element numbers. As can be seen in  FIG.  29   , for example, the first drive shaft axis “FDA” is offset from and parallel with or is substantially parallel with the second drive shaft axis “SDA”. In this arrangement, first and second drive systems  720 ,  740  are powered by a motor  780  through a unique and novel “shiftable” transmission assembly  760 . The first drive system  720  includes a first drive shaft  722  that has a first drive gear  724  keyed thereon or otherwise non-rotatably affixed thereto. Similarly, the second drive system  740  includes a second drive shaft  742  that has a second drive gear  744  keyed thereon or otherwise non-rotatably thereto. The motor  780  includes a motor gear  782  that is non-rotatably attached to the shaft  781  of the motor  780 . 
     In the illustrated arrangement, a second motor  750  is employed to shift the transmission assembly  760  as will be discussed in further detail below. The second motor  750  may be controlled, for example, by the various firing trigger and switch arrangements disclosed herein. The second motor  750  can be controlled in a manner similar to the way that the motor  7038  is controlled as described hereinbelow in connection with  FIGS.  61 ,  63 A,  63 B,  64   . As can be seen in  FIG.  29   , a first transfer pulley  753  is keyed onto or otherwise non-rotatably affixed to the motor shaft  752 . A first pivot shaft  754  is rotatably supported within the housing  12  of the handle  14 . The first pivot shaft defines a pivot axis “PA”. A second transfer pulley  755  is non-rotatably mounted on the first pivot shaft  754  and a transfer belt  756  is mounted on the first and second transfer pulleys  753 ,  755 . In one form, the shiftable transmission assembly  760  includes a transfer link  762  that is attached to the first pivot shaft  754 . In addition, an idler shaft  763  is attached to the transfer link  762  which operably supports an idler gear  764  thereon. The shiftable transmission assembly  760  is movable between a first drive position and a second drive position. To move the shiftable transmission assembly  760  to the first drive position, the clinician actuates the second motor  750  to rotate the pivot shaft  763  and idler gear  764  about pivot axis PA such that it is in meshing engagement with the motor gear  782  and the first drive gear  724 . When in that position, actuation of the motor  780  will then result in actuation of the first drive system  720 . When the clinician desires to actuate the second drive system  740 , the second motor  750  is actuated to rotate the idler gear  764  about pivot axis PA into meshing engagement with the motor gear  782  and the second drive gear  744 . When in that position, actuation of motor  780  results in actuation of the second drive system  740 . One benefit that may be achieved with this arrangement is that precise gear orientation is not required. As the idler gear  764  swings into position, it may be rotating and automatically will find a mating tooth. 
       FIGS.  30 - 32    illustrate a unique and novel motor unit  800  that may be mounted within a housing of the types described herein. The motor unit  800  may include a separate housing structure  801  that operably supports a first motor  802  with a first motor shaft  803  that defines a first drive system  804 . The motor unit  800  may include a second motor  805  with a second motor shaft  806  that defines a second drive system  807 . As can be seen in  FIG.  8   , for example, the first drive shaft axis “FDA” is offset from and parallel with or is substantially parallel with the second drive shaft axis “SDA”. The unit  800  may further include a control circuit board  808  which contacts  808 A that operably interface with corresponding contacts on the circuit board mounted within the instrument housing or otherwise supported therein and communicating with the instrument&#39;s control system. The housing may further include electrical contacts  808 B which are configured to operably interface with corresponding electrical contacts on an end effector tool that is coupled thereto. 
     As illustrated in  FIG.  1   , the modular surgical system  2  may include a variety of different surgical end effector arrangements  1000 ,  2000 , and  3000  that may be used in connection with various surgical instruments described herein. As will be discussed in further detail below, each of the end effectors  1000 ,  2000 ,  3000  include dual, separate “first and second end effector drive systems” that are adapted to operably interface with the first and second drive systems in the surgical instrument to receive control motions therefrom. The end effector drive systems are each configured to linearly move corresponding end effector actuator components from first or beginning linear positions to second or ending linear positions in response to corresponding rotary motions applied to the end effector drive systems by the surgical instrument to which the end effector is operably attached. The end effector actuator components apply linear actuation motions to various end effector components located in the end effector tool head portion in order to perform various surgical procedures. As will be discussed in further detail below, the end effectors employ unique components and systems for assisting the clinician in coupling the first and second drive shafts of the surgical instrument with the corresponding drive shafts in the end effector. Because the four drive shafts are essentially simultaneously coupled together, various coupling arrangements and control techniques may be employed to ensure that the shafts are in the correct positions or “near correct positions” that will facilitate such simultaneous coupling of the drive systems. 
     Referring now to  FIG.  33   , one form of mechanical coupling system  50  may be employed to facilitate the simultaneous removable and operable coupling of the two drive systems in the surgical instrument to the corresponding “driven” shafts in the end effectors. The coupling system  50  may comprise male couplers that may be attached to the drive shafts in the surgical instrument and corresponding female socket couplers that are attached to the driven shafts in the surgical end effector. For example,  FIG.  9    illustrates male couplers  51  attached to the first and second drive shafts  22 ,  42  by set screws  52 . Referring again to  FIG.  33   , each of the male couplers  51  are configured to be drivingly received within corresponding female socket couplers  57  that may also be attached to the driven shafts within the end effector. In one form, each male coupler  51  includes at least three drive ribs  53  that are equally spaced around a center portion  54  of the male coupler  51 . In the illustrated embodiment, for example, five drive ribs  53  are equally spaced around the center portion  54 . Each drive rib  53  has a pointed distal end  55 . Each drive rib  53  may be formed with somewhat rounded edges  56  to facilitate easy insertion into corresponding socket grooves  58  within the female socket coupler  57 . Each socket groove  58  has a tapered proximal entrance portion  59  to facilitate insertion of a corresponding drive rib  53  therein. The pointed distal end  55  of each drive rib  53  in conjunction with the tapered entrance  59  of each socket groove  58  will accommodate some misalignment between the male coupler  51  and its corresponding female socket coupler  57  during the coupling process. In addition, the rounded edges  57  on the pointed distal end  55  also assist in the slidable insertion of the male coupler  51  into the corresponding female socket coupler  58 . 
     In one form, at least one of the male couplers  51  is movably attached to its corresponding first or second drive shaft of the surgical instrument or its corresponding first and second driven shaft of the surgical end effector. More specifically, the male coupler  51  may be attached for radial, or angular, travel on the shaft for a “first predetermined amount of radial travel” on the shaft. This may be accomplished for example, by key and keyway arrangements that are sized relative to each other to facilitate an amount of radial, or angular, travel of the male coupler  51  on the shaft. Stated another way, for example, the shaft may have a key formed thereon or otherwise mounted thereto that is smaller than a corresponding keyway formed in the male coupler  51  such that the key may move within the keyway and establish a first predetermined amount of radial travel. This first predetermined amount of radial travel is preferably sufficient enough to back drive or forward drive the coupler. For a male coupler  51  that has five ribs  53 , for example, the first predetermined range of radial travel may be, for example, 5-37 degrees. Some embodiments may exist where the first predetermined range of radial travel may be less than 5° and preferably not more than 4°, for example. Such range of radial, or angular, travel may be sufficient if, for example, the corresponding female socket coupler  57  was rigidly affixed to its corresponding drive shaft and otherwise was incapable of any radial travel. However, if both the male and female couplers have the ability to radially, or angularly, adjust, such range of radial, or angular, travel may be reduced by 50% to provide each coupler (male coupler and corresponding female socket coupler) with a range of travel of about 3-16 degrees. The amount of radial, or angular, travel that a female socket coupler  57  may move on its corresponding shaft may be referred to herein as a “second predetermined amount of radial travel”. The female socket couplers  57  may also be attached to their respective drive shafts with a key and keyway arrangement as described above that provides the desired second predetermined amount of radial travel. Some embodiments may exist where the second range of predetermined radial travel may be less than 5° and preferably not more than 4°, for example. 
     Various combinations and mounting arrangements of the male couplers and the female socket couplers are contemplated. For example, one or both of the male couplers may be movably mounted to their respective drive shafts of the surgical instrument (or driven shafts of the surgical end effector) in the various manners described herein. Likewise one or both of the female socket couplers may be movably mounted to their respective driven shafts on the end effector (or drive shafts of the surgical instrument) in the various manners described herein. For example, a male coupler on one of the first and second drive shafts may be movably mounted thereon. The other male coupler that is attached to the other drive shaft may be non-movably mounted thereto. The female socket coupler on the driven shaft that corresponds to the movably mounted male coupler may be non-movably attached to its driven shaft and the female socket coupler mounted on the other driven shaft that corresponds to the non-movably mounted coupler may be movably mounted to its driven shaft. Thus, one of a male coupler and a female coupler socket of a “coupler pair” is movable. The term “coupler pair” refers to the male coupler and corresponding female socket coupler that is configured to be coupled together to operably couple a drive shaft of the surgical instrument to its corresponding driven shaft of the end effector. In other arrangements both the male coupler and female coupler socket of a coupler pair may both be movably coupled to their respective shafts. 
     Such coupler arrangements serve to provide a small amount of angular slack, for example, between the coupler components so that the components may rotate slightly for sufficient alignment which will permit simultaneous alignment of the coupler components attached to the two separate rotary drive trains. In addition, there may be a sufficient amount of backlash or slack provided in the drive trains to accommodate the coupling process. Such backlash or slack may be provided by forming keys/keyways into the gears, couplers and or mating shafts to facilitate such slight rotation of components. In addition, a switch arrangement may be employed in connection with the various shiftable transmission assemblies which may activate the motor to cause a slight rotation of the drive shafts for coupling purposes. This and other control techniques may be employed to ensure that the drive shafts in the surgical instruments are positioned in desired positions that facilitate their coupling with the corresponding drive shafts in the end effectors. The unique and novel mechanical coupling system  50  serves to provide some additional flexibility during the coupling process to enable the drive shafts to be coupled together in the event that there is some misalignment between the respective shafts. It will be understood that although the various embodiments described herein illustrate the male couplers  51  attached to the drive shafts within the surgical instrument and the female socket couplers  58  attached to the end effector drive shafts, the male couplers  51  could be attached to the end effector drive shafts and the female socket couplers  58  could be attached to the instrument drive shafts. 
       FIGS.  34 - 37    depict a surgical end effector  1000  that comprises a surgical cutting and fastening instrument of a type that is commonly referred to as an “open linear” stapler. Various forms of such open linear stapling devices are disclosed in, for example, U.S. Pat. No. 5,415,334, entitled SURGICAL STAPLER AND STAPLE CARTRIDGE and U.S. Pat. No. 8,561,870, entitled SURGICAL STAPLING INSTRUMENT, the entire disclosures of each being hereby incorporated by reference herein. The end effector  1000  comprises an end effector housing  1010  that may be fabricated from housing segments  1012 ,  1014  that are removably coupled together by screws, lugs, snap features, etc. Protruding from the end effector housing  1010  are a lower jaw  1020  and an upper jaw  1040  which may collectively form the end effector tool head  1004 . The lower jaw  1020  comprises a lower jaw frame  1022  that is configured to operably support a surgical staple cartridge  1060  therein. Such surgical staple cartridges are well known in the art and will therefor not be described in great detail herein. Briefly, the surgical staple cartridge  1060  may comprise a cartridge body  1062  that has lines of staple pockets  1066  formed therein on each lateral side of an elongate slot  1068  that is centrally disposed within cartridge body  1062 . The slot  1068  is configured to accommodate the longitudinal travel of a cutting member  1090  therethrough as will be discussed in further detail below. A surgical staple or staples (not shown) are supported in the staple pockets  1066  on staple drive members (not shown) that are configured to move upward within their respective pocket  1066  during a firing process. The staple cartridge  1060  may be configured to be removed from the lower jaw frame  1022  and replaced with another unspent cartridge making the end effector  1000  reusable. However, the end effector  1000  may also be disposable after a single use. 
     Referring to  FIG.  36   , the lower jaw frame  1022  may be formed from metal material and have a U-shaped distal portion  1024  that is configured to seatingly receive the surgical staple cartridge  1060  therein. The side walls  1026  of the U-shaped distal portion  1024  may have a distal end  1028  that is configured to releasably and retainingly engage a portion of the surgical cartridge  1060 . The staple cartridge body  1062  may also have engagement features  1064  that are adapted to releasably engage upstanding wall portions  1030  of the lower jaw frame  1022 . The end effector  1000  further comprises an upper jaw  1040  that includes an anvil portion  1042 . The anvil portion  1042  may include an underside (not shown) that has a plurality of staple-forming pockets therein. The upper jaw  1040  further includes a proximal body portion  1044  that has a distal trunnion pin  1046  extending therethrough. The ends of the distal trunnion pin  1046  that protrude laterally from the proximal end of the proximal body portion  1044  are rotatably received within trunnion holes  1032  in the lower jaw  1020 . The trunnion pin  1046  defines an attachment axis AA-AA about which the proximal end of the upper jaw  1040  pivots relative to the lower jaw  1020  such that the anvil portion  1042  is movable between an open position spaced from the staple cartridge  1060  mounted within the lower jaw  1020  and a closed position adjacent the staple cartridge  1060  and/or tissue that is located therebetween. The end effector  1000  may further include a transverse fulcrum pin  1050  that is received within cradles  1034  formed in the upstanding walls  1030  of the lower jaw  1020  and is mounted within holes  1016  in the housing segments  1012 ,  1014 . The fulcrum pin  1050  may serve as a fulcrum axis or surface about which the anvil portion  1042  pivots. 
     The movement of the anvil portion  1042  between the open and closed positions is controlled by a first end effector drive system also referred to herein as the end effector closure system  1070 . In one form, for example, the end effector closure system  1070  includes a closure shuttle  1072  that extends around the proximal body portion  1024  of the lower jaw  1020 . The closure shuttle  1072  may also be referred to as a “first end effector actuator”. The closure shuttle  1072  may include a U-shape portion that includes distal upstanding walls  1074  and proximal upstanding walls  1076 . Each distal upstanding wall  1074  includes an arcuate cam slot  1078  that is adapted to receive a corresponding portion of a cam pin  1048  that is attached to the upper jaw  1040 . Thus, axial or linear movement of the closure shuttle  1072  relative to the lower jaw  1020  will cause the upper jaw  1040  to pivot on the fulcrum pin  1050  and about the attachment axis AA-AA by virtue of the interaction of the cam pin  1048  within the cam slots  1078 . 
     In various forms, the closure system  1070  includes a rotary end effector closure shaft  1080  that is threaded and includes a distal end portion  1082  that is rotatably supported within the end effector housing  1010 . The end effector closure shaft  1080  defines a closure shaft axis CSA-CSA. See  FIG.  37   . A female socket coupler  57  is attached to the proximal end of the closure shaft  1080  to facilitate coupling of the closure shaft  1080  with a male coupler  51  attached to a first drive shaft in a surgical instrument. The closure system  1070  further includes a closure nut  1084  that is threadably received on the closure shaft  1080 . The closure nut  1084  is configured to be seated within mounting slots  1077  in the upstanding walls  1076  of the closure shuttle  1072 . Thus, rotation of the closure shaft  1080  in a first direction will cause the closure nut  1084  to drive the closure shuttle  1072  in the distal direction “DD”. Movement of the closure shuttle  1072  in the distal direction “DD” results in the pivotal travel of the upper jaw  1040  from an open position to a closed position. Likewise, movement of the closure shuttle  1084  in the proximal direction “PD” will result in the movement of the upper jaw  1040  from a closed position back to an open position. 
     The end effector  1000  further includes a second end effector drive system also referred to herein as a firing system  1100  for driving a tissue cutting member  1090  and wedge sled assembly  1092  between starting and ending positions. When the wedge sled assembly  1092  is driven distally through the surgical staple cartridge  1060 , the wedge sled assembly  1092  operably interacts with the drivers within the cartridge  1060  that have surgical staples supported thereon. As the wedge sled assembly  1092  is driven distally, the drivers are driven upward within their respective pockets to drive the staples supported thereon into forming engagement with the underside of the anvil portion  1042  of the upper jaw  1040 . In one form, the firing system  1100  further includes a rotary threaded firing shaft  1102  that is rotatably supported in the end effector housing  1010 . The firing shaft  1102  defines a firing shaft axis FSA-FSA that is parallel with or substantially parallel with the closure shaft axis CSA-CSA. See, e.g.,  FIG.  37   . The firing shaft  1102  includes a distal end portion  1104  that is rotatably supported in a mounting unit  1106  that is mounted within the end effector housing  1010 . A female socket coupler  57  is attached to the proximal end of the firing shaft  1102  to facilitate coupling of the firing shaft  1102  with a male closure coupler  51  that is attached to a second drive shaft in a surgical instrument. The firing system  1100  further includes a firing nut  1110  that is threadably received on the firing shaft  1102 . Thus, rotation of the firing shaft  1102  results in the axial travel of the firing nut  1110  within the end effector housing  1010 . In one form, the tissue cutting member  1090  and wedge sled assembly  1092  are coupled to the firing nut  1110  by a firing bar or firing bars  1112 . The firing bar or bars may also be referred to herein as a “second end effector actuator” that is linearly or axially moved in response to actuation of the firing system. Thus, rotation of the firing shaft  1102  in a first direction will drive the firing nut  1110 , firing bar(s)  1112 , the tissue cutting member  1090  and the wedge sled assembly  1092  in the distal direction “DD” from, for example, a starting position ( FIG.  35   ) to an ending position wherein the tissue cutting member  1090  and wedge sled assembly  1092  have been driven to the distal end of the surgical staple cartridge  1060 . Rotation of the firing shaft  1102  in an opposite direction will drive the firing nut  1110 , the firing bar(s)  1112 , the tissue cutting member  1090  and the wedge sled assembly  1092  in a proximal direction “PD” from their respective ending positions back to their respective starting positions. In some embodiments, the wedge sled assembly may remain at the distal end of the surgical staple cartridge and not return with the tissue cutting member  1090  to the starting position. In still other embodiments, the tissue cutting member and the wedge sled assembly member may remain at the distal end of the staple cartridge member. 
     The end effector  1000  may also be equipped with various sensors that are coupled to an end effector contact board  1120  mounted within the end effector housing  1010 . The contact board  1120  may be positioned with the end effector housing  1020  such that when the end effector  1000  is operably coupled to the surgical instrument, the end effector contact board  1120  is electrically coupled to a surgical instrument contact board  30  mounted in the surgical instrument housing  12 . See, e.g.,  FIG.  1   . Referring again to  FIG.  34   , a closure sensor  1122  may be mounted within the end effector housing  1010  and be electrically coupled to the end effector contact board  1120  such that when the end effector  1000  is operably coupled to the surgical instrument, the closure sensor  1122  is in communication with the surgical instrument&#39;s control system. The closure sensor  1122  may comprise a Hall effect sensor  7028  as shown hereinbelow, for example, in connection with  FIGS.  61 ,  63 A,  63 B  that is configured to detect the position of a switch lug  1086  on the closure nut  1084 . In addition, a firing sensor  1124  may also be mounted within the end effector housing  1010  to detect the presence of a firing bar  1112 . The firing sensor  1112  may comprise a Hall effect sensor  7028  as shown hereinbelow, for example, in connection with  FIGS.  61 ,  63 A,  63 B , and be electrically coupled to the end effector contact board  1120  for ultimate communication with the surgical instrument control system, such as the handle processor  7024  as will be discussed in further detail below in connection with  FIGS.  61 ,  63 A,  63 B,  64   . 
     Use of the end effector  1000  will now be explained in connection with surgical instrument  10 . It will be appreciated, however, that the end effector  1000  may be operably coupled to various other surgical instrument arrangements disclosed herein. Prior to use, the closure shaft  1080  and the firing shaft  1102  are “clocked” or positioned in their respective starting positions to facilitate attachment to the first and second drive shafts  22 ,  42 , respectively. To couple the end effector  1000  to the surgical instrument  10 , for example, the clinician moves the end effector  1000  into a position wherein the closure shaft axis CA-CA is in axial alignment with the first drive shaft axis FDA-FDA and wherein the firing shaft axis FSA-FSA is in axial alignment with the second drive shaft axis SDA-SDA. The female socket coupler  57  on the closure shaft  1080  is inserted into operable engagement with the male coupler  51  on the first drive shaft  22 . Likewise, the female socket coupler  57  on the firing shaft  1102  is inserted into operable engagement with the male coupler  51  on the second drive shaft  42 . Thus, when in that position, the closure shaft  1080  is operably coupled to the first drive shaft  22  and the firing shaft  1102  is operably coupled to the second drive shaft  42 . The end effector contact board  1120  is operably coupled to the surgical instrument contact board  30  so that the sensors  1122 ,  1124  (and any other sensors within the end effector  1000 ) are in operable communication with the surgical instrument&#39;s control system. To retain the end effector  1000  in coupled operable engagement with the surgical instrument  10 , the end effector  1000  includes a retainer latch  1130  that is attached to the end effector housing  1010  and configured to releasably engage a portion of the instrument housing  12 . The retainer latch  1130  may include a retention lug  1132  that may releasable engage a retainer cavity  15  formed in the housing  12 . See  FIG.  1   . 
     When coupled together, the closure sensor  1122  detects the position of the closure nut  1084  and the firing sensor  1124  detects the position of the firing bar  1112 . That information is communicated to the surgical instrument control system. In addition, the clinician may confirm that the shiftable transmission assembly (or the transmission carriage  62  thereof) is in its first drive position. This may be confirmed by the actuation of the indicator light  77  on the housing  12  as discussed above. If the shiftable transmission assembly  60  is not in its first drive position, the clinician may actuate the firing trigger  92  to move the transmission carriage  62  into the first drive position, such that actuation of the rocker trigger  110  to actuate the motor  80  will result in actuation of the first drive system  20 . Assuming that the closure system  1070  and firing system  1100  are each in their respective starting positions and the end effector  1000  has an unspent staple cartridge  1060  properly installed therein, the clinician can then position the jaws  1020 ,  1040  relative to the target tissue to be cut and stapled. The clinician may close the upper jaw  1040  by actuating the rocker trigger  110  to actuate the motor  80  and rotate the first drive shaft  22 . Once the target tissue has been clamped between the upper jaw  1040  and the surgical staple cartridge  1060  in the lower jaw  1020 , the clinician may then actuate the firing trigger  92  to move the transmission carriage  62  to its second drive position such that actuation of the motor  80  will result in the rotation of the second drive shaft  42 . Once the transmission carriage  62  is moved to the second drive position, the clinician may once again actuate the rocker trigger  110  to actuate the second drive system  40  and the firing system  1100  in the end effector  1000  to drive the tissue cutting member  1090  and wedge sled assembly  1092  distally through the surgical staple cartridge  1060 . As the tissue cutting member  1090  and wedge sled assembly  1092  are driven distally, the target tissue clamped between the jaws  1020 ,  1040  is cut and stapled. Once the tissue cutting member  1090  and wedge sled assembly  1092  have been driven to their distal-most positions in the surgical staple cartridge  1060 , the clinician can actuate the rocker trigger  110  to reverse the motor rotation and return the firing system  1100  to its starting position. 
     When employing end effector  1000  and other end effector and surgical instruments disclosed herein containing similar jaw arrangements it can be challenging to adequately clean the anvil pockets in the underside of the anvil. In addition, the anvil pockets can gall, scive or simply wear over time making them ill-suited for reuse. Furthermore, depending upon the application, loading and removing of the surgical staple cartridge may be difficult.  FIGS.  119 - 121    illustrate a single-use “staple pack”  1300  that may address some, if not all, of these challenges. 
       FIG.  119    depicts a portion of an end effector  1000 ′ that may be similar in construction and operation to, for example, end effector  1000  as well as other end effectors disclosed herein except for the specific differences discussed below. As can be seen in  FIG.  119   , the upper jaw  1240  includes an open distal end  1243 . The upper jaw  1240  may be formed form metal material and have a U-shaped configuration when viewed from the distal end and include two-inwardly-extending, opposed retention lips  1245 . The end effector  1000 ′ further includes a lower jaw frame  1222  that is similar to, for example, lower jaw frame  1222  described herein. As can be seen in that Figure, the lower jaw fame  1222  also has an open distal end  1223 . 
     Still referring to  FIG.  119   , one form of “single-use” staple pack  1300  includes an anvil  1302  that has a staple-forming surface  1304  that includes a plurality of staple-forming pockets (not shown) that are formed therein. The staple pack  1300  further includes a staple cartridge  1310  that has a cartridge deck  1312  that is configured for spaced confronting relationship to the staple-forming undersurface  1304  of the anvil  1302 . The staple cartridge  1310  may be similar to other staple cartridges disclosed in further detail herein and operably support a plurality of surgical staples therein. The staple pack  1300  further includes a disposable keeper member  1320  that is sized and shaped to frictionally engage the anvil  1302  and staple cartridge  1310  in such a manner as to maintain alignment between the staple pockets in the staple-forming undersurface  1304  and the staples (not shown) within the staple cartridge  1310  prior to use. The keeper  1320  may also include a spacer strip  1322  that extends between the anvil  1302  and the staple cartridge  1310 . The keeper may, for example, be molded from plastic or other suitable polymer material and the spacer strip  1322  may be fabricated from metal material. The spacer strip  1322  may be frictionally retained in a slot or other retention feature formed in the keeper  1320 . 
     Referring now to  FIG.  120   , the staple pack  1300  is installed by aligning the anvil  1302  with the open distal end  1243  in the upper jaw  1240  and the staple cartridge  1310  is aligned with the open distal end  1245  in the lower jaw frame  1222 . Thereafter, the staple pack  1300  is moved in the proximal direction “PD” to the position illustrated in  FIG.  120   . The retention lips  1245  serve to support the anvil  1302  within the upper jaw  1240 . The end effector  1000 ′ may also include a manually actuatable latch feature  1340  that may be moved from an unlatched position ( FIG.  119   ) to a latched position ( FIG.  121   ). When in the latched position, for example, the latch feature  1340  retains the anvil  1302  within the upper jaw  1240  and the staple cartridge  1310  within the lower jaw frame  1222 . For example, the latch feature  1340  may include a movable upper latch arm  1342  that is configured to releasably engage a portion (e.g., lip, detent, ledge or other retention feature(s)) formed on the proximal end of the anvil  1302 . Similarly the latch feature  1340  may include a movable lower latch arm  1344  that is configured to releasably engage a portion (e.g., lip, detent, ledge or other retention feature(s)) formed on the staple cartridge  1310 . The upper and lower latch arms  1342 ,  1344  may be pivotally or otherwise movably supported on the end effector  1000 ′ for selective movement between the latched and unlatched positions. In various forms the upper and lower latch arms  1342 ,  1344  may be normally biased into the latched position by a spring or springs (not shown). In such arrangements, the clinician may insert the staple pack  1300  into the upper jaw  1240  and lower jaw frame  1222 . As the proximal end of the anvil  1302  contacts the upper latch arm  1342 , the upper latch arm  1342  is pivoted or moved to permit the anvil  1302  to be seated into position. Once the anvil is seated in position, the upper latch arm  1342  is biased into latching engagement with the anvil  1302  (if a spring or biasing member is employed). In alternative arrangements, the upper latch arm  1342  may be manually moved into the latched position. Likewise, as the proximal end of the staple cartridge  1310  contacts the lower latch arm  1344 , the lower latch arm  1344  is pivoted or moved to permit the staple cartridge  1310  to be seated into position. Once the staple cartridge  1310  is seated in position, the lower latch arm  1344  is biased into latching engagement with the staple cartridge  1310  to retain it in position (if a spring or biasing arrangement is employed). In alternative embodiments, the lower latch arm  1344  may be manually moved to the latched position. Once the staple pack  1300  has been installed and the anvil  1302  and staple cartridge  1310  have been latched or otherwise attached to the end effector  1000 ′, the clinician may remove the keeper assembly  1320 . See, e.g.,  FIG.  121   . After the staple pack  1300  has been used, the clinician may then replace the keeper  1320  onto the distal ends of the anvil  1302  and the staple cartridge  1310 . This may be accomplished by aligning the open end of the keeper member  1320  and then pressing the keeper member  1320  back into frictional engagement with the anvil  1302  and staple cartridge  1310 . Once the distal ends of the anvil  1302  and staple cartridge  1310  have been seated into the keeper member  1320 , the clinician may move the upper and lower latch arms  1342 ,  1344  to their an unlatched positions to enable the staple pack  1300  to be pulled out of the upper jaw  1240  and lower jaw frame  1222 . Thereafter, the staple pack  1300  may be discarded as a unit. In other situations, the clinician may separately remove the anvil  1302  and staple cartridge  1310  from the end effector  1000 ′ without first installing the keeper member  1320 . 
       FIGS.  38 - 41    depict a surgical end effector  2000  that comprises a surgical cutting and fastening instrument of a type that may commonly be referred to as a “curved cutter stapler”. Various forms of such stapling devices are disclosed in, for example, U.S. Pat. No. 6,988,650, entitled RETAINING PIN LEVER ADVANCEMENT MECHANISM FOR A CURVED CUTTER STAPLER and U.S. Pat. No. 7,134,587, entitled KNIFE RETRACTION ARM FOR A CURVED CUTTER STAPLER the entire disclosures of each being hereby incorporated by reference herein. The end effector  2000  comprises an end effector housing  2010  that may be fabricated from housing segments  2012 ,  2014  that are removably coupled together by screws, lugs, snap features, etc. Protruding from the end effector housing  2010  is an elongated frame assembly  2020  that terminates in an end effector tool head  2002 . In one form, the frame assembly  2020  comprises a pair of spaced frame struts or plates  2022  that are fixedly attached to the housing  2010  and protrude distally therefrom. A C-shaped supporting structure  2024  is attached to the distal end of the frame plates  2022 . The term “C-shaped” is used throughout the specification to describe the concave nature of the supporting structure  2024  and a surgical cartridge module  2060 . The C-shaped construction facilitates enhanced functionality and the use of the term C-shaped in the present specification should be construed to include a variety of concave shapes which would similarly enhance the functionality of surgical stapling and cutting instruments. The supporting structure  2024  is attached to the frame plates  2022  by a shoulder rivet  2023  and posts  2026  which extend from the supporting structure  2024  into receiving holes in the frame plates  2022 . In various forms, the supporting structure  2024  may be formed via a single piece construction. More specifically, the supporting structure  2024  may be formed from extruded aluminum material. By forming the supporting structure  2024  in this manner, multiple parts are not required and the associated cost of manufacture and assembly is substantially reduced. In addition, it is believed the unitary structure of the supporting structure  2024  enhances the overall stability of the end effector  2000 . Furthermore, the unitary extruded structure of the supporting structure  2024  provides for a reduction in weight, easier sterilization since cobalt irradiation will effectively penetrate the extruded aluminum and less trauma to tissue based upon the smooth outer surface achieved via extrusion. 
     The end effector  2000  further includes a first end effector drive system also referred to as end effector closure system  2070  and a second end effector drive system also referred to herein as a firing system  2100 . In one form, for example, the end effector closure system  2070  includes a closure beam assembly  2072  that is sized to be slidably received between the frame struts  2022  for axial travel therebetween. The closure beam assembly  2072  may also be referred to as a first end effector actuator and has an open bottom configured to slidably receive a firing bar assembly  2112  of the firing system  2100  as will be discussed in further detail below. In one form, for example, the closure beam assembly  2072  is a molded plastic member shaped for movement and functionality as will be further discussed below. By manufacturing the closure beam assembly  2072  from plastic, manufacturing costs may be reduced and the weight of the end effector  2000  may also be reduced. In addition, the end effector  2000  may be easier to sterilize with cobalt irradiation as plastic is easier to penetrate than stainless steel. In accordance with an alternate arrangement, the closure beam assembly  2072  may be made from extruded aluminum with the final features machined into place. While an extruded aluminum closure beam assembly might not be as easy to manufacture as the plastic component, it would still have the same advantages (i.e., elimination of components, easier to assemble, lower weight, easier to sterilize). 
     The closure beam assembly  2072  includes a curved distal end  2074  that is sized to be received between the side walls  2027  of the supporting structure  2024 . The curved distal end  2074  is sized and shaped to receive and retain a cartridge housing  2062  of the cartridge module  2060 . In various forms, the proximal end of the closure beam assembly  2072  is coupled to a closure nut  2084  that is threadably received on a threaded closure shaft  2080 . The closure shaft  2080  defines a closure shaft axis CSA-CSA and has a female socket coupler  57  is attached to its proximal end to facilitate coupling of the closure shaft  2080  with a male coupler  51  attached to a first drive shaft in a surgical instrument. Rotation of the closure shaft  2080  in a first direction will cause the closure nut  2084  to drive the closure beam assembly  2072  in the distal direction “DD”. Rotation of the closure shaft  2080  in an opposite direction will likewise result in the proximal travel of the closure nut  2084  and the closure beam assembly  2072 . 
     As indicated above, the distal end  2074  of the closure beam assembly  2072  is configured to operably support the cartridge housing  2062  of a cartridge module  2060  therein. The cartridge module  2060  includes a plurality of surgical staples (not shown) on a staple driver (not shown) that, when axially advanced, drives the surgical staples out of their respective pockets  2066  positioned on each side of a slot  1068  that is configured to accommodate the passage of a knife member  2115  therethrough. The cartridge module  2060  may, for example, be somewhat similar to the cartridge modules disclosed in, for example, U.S. Pat. Nos. 6,988,650 and 7,134,587, which have both been incorporated by reference in their respective entireties herein excepted for any noted differences. The end effector  2000  may be disposed of after a single use or the end effector  2000  may be reusable by replacing the spent cartridge module during an ongoing procedure or for a new procedure after being resterilized. 
     The end effector  2000  further includes a firing system  2100  which includes a firing bar assembly  2112  that is configured to be slidably received within the open bottom of the closure beam assembly  2072 . See  FIG.  39   . In one form, the firing system  2100  further includes a firing shaft  2102  that has a threaded distal end  2104  and a proximal portion  2106  that has a square cross-sectional shape. The threaded distal end  2104  is threadably received within a threaded firing nut  2110  that is attached to the proximal end of the firing bar assembly  2112 . The threaded firing nut  2110  is sized to be slidably received within an axial cavity  2085  within the closure nut assembly  2084 . See  FIG.  41   . Such arrangement permits the firing nut  2110  to be axially advanced with the closure nut assembly  2084  when the end effector  2000  is moved to a closed position and then move axially relative to the closure nut  2084  and closure beam assembly  2072  when the firing system  2100  is actuated. The firing shaft  2102  defines a firing shaft axis FSA-FSA that is parallel with or substantially parallel with the closure shaft axis CSA-CSA. See, e.g.,  FIG.  41   . As can also be seen in  FIGS.  39  and  41   , the proximal portion  2106  of the firing shaft  2102  is slidably received within an elongated passage  2105  within a female socket coupler  57 ′ that is otherwise identical to the female socket couplers described herein. The elongated passage  2105  has a square cross-sectional shape that is sized to slidably receive the proximal portion  2106  of the firing shaft  2102  therein. Such arrangement permits the firing shaft  2102  to move axially relative to the female socket coupler  57 ′ while being rotatable with the female socket coupler  57 ′. Thus, when the closure beam assembly  2072  is advanced in the distal direction “DD” upon actuation of the first drive system in the surgical instrument, the firing nut  2110  will be carried in the distal direction “DD” within the closure nut assembly  2084 . The proximal portion  2106  of the firing shaft  2102  will move axially within the passage  2105  in the female socket coupler  57 ′ while remaining engaged therewith. Thereafter, activation of the second drive system in one rotary direction in the surgical instrument which is operably coupled to the female socket coupler  57 ′ will rotate the firing shaft  2102  which will cause the firing bar assembly  2112  to move in the distal direction “DD”. As the firing bar assembly  2112  moves in the distal direction, the knife bar  2115  is advanced distally through the cartridge module  2060 . Actuation of the second drive system in a second rotary direction will cause the firing bar assembly  2112  to move in the proximal direction “PD”. 
     The distal end of the firing bar assembly  2112  includes a drive member  2114  and the knife member  2115  that protrudes distally therefrom. As can be seen in  FIG.  39   , the knife member  2115  is slidably received within an anvil arm portion  2142  of an anvil assembly  2140  that is configured to be seated within a curved anvil support portion  2025  of the support structure  2024 . Further details regarding the anvil assembly  2140  may be found in U.S. Pat. Nos. 6,988,650 and 7,134,587. The end effector  2000  may also include a safety lockout mechanism  2150  ( FIG.  39   ) for preventing the firing of a previously fired cartridge module  2060 . Details regarding the interaction between the cartridge module  2060  and the safety lockout mechanism may be found in U.S. Pat. Nos. 6,988,650 and 7,134,587. 
     The end effector  2000  also includes a tissue retaining pin actuation mechanism  2160 . The tissue retaining pin actuation mechanism  2160  includes a saddle shaped slide  2162  that is positioned on a top portion of the housing  2010 . The slide  2162  is pivotally connected to a push rod driver  2163  that is slidably supported within the housing  2010 . The push rod driver  2163  is restrained for longitudinal movement along the long axis of the end effector  2000 . The push rod driver  2163  is connected to a push rod  2164  by a circumferential groove  2165  on the push rod  2164  that snaps into a slot  2166  of the push rod driver  2163 . See  FIG.  41   . The distal end of the push rod  2164  contains a circumferential groove  2167  that interconnects with a groove  2172  in a proximal end of a coupler  2170  that is attached to the cartridge module  2160  (best seen in  FIG.  41   ). The distal end of the coupler  2170  contains a groove  2174  for interconnecting with a circumferential slot  2182  on a retaining pin  2180 . Manual movement of the slide  2162  results in movement of the push rod  2164 . The distal movement or proximal retraction of the push rod  2164  results in corresponding movement of the retaining pin  2180 . The retaining pin  2180  actuation mechanism  2160  also operably interacts with the closure beam assembly  2072  such that actuation of the closure system  2070  will result in automatic distal movement of the retaining pin  2180  if it has not already been manually moved to its most proximal position. When the retaining pin  2180  is advanced, it extends through the cartridge housing  2062  and into the anvil assembly  2140  to thereby capture tissue between the cartridge module  2060  and the anvil assembly  2140 . 
     In one form, the retaining pin actuation mechanism  2160  includes a yoke  2190  rotationally or pivotally supported within the housing  2010  via a pivot pin  2192 . The closure beam assembly  2072  further includes posts or lugs  2073  which extend laterally on both sides of the closure beam assembly  2072  inside the housing  2010 . These posts  2073  are slidably received within corresponding arcuate slots  2194  in the yoke  2190 . The yoke  2190  contains cam pins  2196  positioned to push camming surfaces  2168  on the push rod driver  2163 . The yoke  2190  is not directly attached to the retaining pin  2180  so the surgeon, if they chose, can advance the retaining pin  2180  manually. The retaining pin  2180  will advance automatically if the surgeon chooses to leave the retaining pin  2180  alone when the closure beam assembly  2072  is advanced distally to a closed position. The surgeon must retract the retaining pin  2180  manually. By constructing the retaining pin actuation mechanism  2160  in this manner, manual closing and retracting of the retaining pin  2180  is permitted. If the surgeon does not manually close the retaining pin  21280 , the present retaining pin actuation mechanism  2160  will do it automatically during instrument clamping. Further details regarding actuation and use of the retaining pin may be found in U.S. Pat. Nos. 6,988,650 and 7,134,587. 
     The end effector  2000  may also be equipped with various sensors that are coupled to an end effector contact board  2120  mounted within the end effector housing  2010 . For example, the end effector  2000  may include a closure sensor  2122  that is mounted within the end effector housing  2010  and is electrically coupled to the end effector contact board  2120  such that when the end effector  2000  is operably coupled to the surgical instrument, the closure sensor  2122  is in communication with the surgical instrument&#39;s control system. The closure sensor  2122  may comprise a Hall effect sensor  7028  as shown hereinbelow in connection with  FIGS.  61 ,  63 A,  63 B  that is configured to detect the position of a switch lug  2086  on the closure nut  21084 . See  FIG.  40   . In addition, a firing sensor  2124  may also be mounted within the end effector housing  2010  and be arranged to detect the location of the firing nut  2110  within the closure nut  2084 . The firing sensor  2124  may comprise a Hall effect sensor  7028  as described hereinbelow in connection with  FIGS.  61 ,  63 A,  63 B  and be electrically coupled to the end effector contact board  2120  for ultimate communication with the surgical instrument control system as discussed herein. The contact board  2120  may be positioned with the end effector housing  2020  such that when the end effector  2000  is operably coupled to the surgical instrument, the end effector contact board  2120  is electrically coupled to a surgical instrument contact board  30  mounted in the surgical instrument housing  12  as was discussed above. 
     Use of the end effector  2000  will now be explained in connection with surgical instrument  10 . It will be appreciated, however, that the end effector  2000  may be operably coupled to various other surgical instrument arrangements disclosed herein. Prior to use, the closure shaft  2080  and the firing shaft  2102  are “clocked” or positioned in their starting positions to facilitate attachment to the first and second drive shafts  22 ,  42 , respectively. To couple the end effector  2000  to the surgical instrument  10 , for example, the clinician moves the end effector  2000  into a position wherein the closure shaft axis CSA-CSA is in axial alignment with the first drive shaft axis FDA-FDA and wherein the firing shaft axis FSA-FSA is in axial alignment with the second drive shaft axis SDA-SDA. The female socket coupler  57  on the closure shaft  2080  is inserted into operable engagement with the male coupler  51  on the first drive shaft  22 . Likewise, the female socket coupler  57 ′ on the firing shaft  2102  is inserted into operable engagement with the male coupler  51  on the second drive shaft  42 . Thus, when in that position, the closure shaft  2080  is operably coupled to the first drive shaft  22  and the firing shaft  2102  is operably coupled to the second drive shaft  42 . The end effector contact board  1120  is operably coupled to the surgical instrument contact board  30  so that the sensors within the end effector  2000  are in operable communication with the surgical instrument&#39;s control system. To retain the end effector  2000  in coupled operable engagement with the surgical instrument  10 , the end effector  2000  includes a retainer latch  2130  that is attached to the end effector housing  2010  and is configured to releasably engage a portion of the instrument housing  12 . The retainer latch  2130  may include a retention lug  2132  that may releasable engage a retainer cavity  15  formed in the housing  12 . See  FIG.  1   . When coupled together, the closure sensor  2122  detects the position of the closure nut  2084  and the firing sensor  2124  detects the position of the firing nut  2110 . That information is communicated to the surgical instrument control system. In addition, the clinician may confirm that the shiftable transmission assembly (or the transmission carriage  62  thereof) is in its first drive position. This may be confirmed by the actuation of the indicator light  77  on the housing  12  as was discussed above. If the shiftable transmission assembly  60  is not in its first drive position, the clinician may actuate the firing trigger  92  to move the transmission carriage  62  into the first drive position, such that actuation of the rocker trigger  110  to actuate the motor  80  will result in actuation of the first drive system  20 . Assuming that the closure system  2070  and firing system  2100  are each in their respective starting positions and the end effector  2000  has an unspent staple cartridge module  2060  properly installed therein, the clinician can then actuate the closure system  2070  to capture the target tissue between the cartridge module  2060  and the anvil assembly  2140 . 
     The clinician may move the closure beam assembly  2072  distally by actuating the rocker trigger  110  to actuate the motor  80  and rotate the first drive shaft  22 . This actuation moves the cartridge module  2060  toward the anvil assembly  2140  to clamp the target tissue therebetween. As the closure beam  2072  moves distally, the interaction of the posts  2073  and the yoke  2190  will cause actuation of the tissue retaining actuation mechanism  2160  to drive the retaining pin  2180  distally through the deck portion  2161  and through the anvil assembly  2140  into a pin pocket  2141  (See  FIG.  41   ) therein. The retaining pin  2180  serves to trap the target tissue between the anvil assembly  2140  and the cartridge module  2060 . Once the target tissue has been clamped between the anvil assembly  2140  and the cartridge module  2060 , the clinician may then actuate the firing trigger  92  to move the transmission carriage  62  to its second drive position such that actuation of the motor  80  will result in the rotation of the second drive shaft  42 . Once the transmission carriage  62  is moved to the second drive position, the clinician may once again actuate the rocker trigger  110  to actuate the second drive system  40  and the firing system  2100  in the end effector  2000  to drive the firing bar assembly  2112  distally which also drives the knife member  2115  distally through the cartridge module  2060  cutting the target tissue clamped between the anvil assembly  2140  and the cartridge module  2060 . As the firing bar assembly  2112  moves distally, the drive member  2114  also drives the surgical staples supported in the cartridge module  2060  out of the cartridge module  2060  through the target tissue and into forming contact with the anvil assembly  2140 . Once the cutting and stapling action is completed, the clinician can actuate the rocker trigger  110  to reverse the motor rotation and return the firing system  2100  to its starting position. The clinician may then return the transmission carriage  62  to its first drive position by means of the firing trigger  92  such that actuation of the rocker trigger  110  in the opposite direction will cause the motor  80  to rotate in a reverse direction to return the closure beam assembly  2073  to its starting position. As the closure beam assembly  2073  moves in the proximal direction, the yoke  2190  may interact with the tissue retaining pin actuation mechanism  2160  to withdraw the retaining pin  2180  to its starting position. In the alternative, the clinician may manually retract the retention pin  2180  to its starting position using the saddle shaped slide  2162 . The clinician may retract the retention pin  2180  to its starting position prior to actuating the closure system  2070  to return the closure beam  2072  to its starting position. Further details regarding use of curved staple cutters may be found in U.S. Pat. Nos. 6,988,650 and 7,134,587. 
       FIGS.  42 - 45    depict a surgical end effector  3000  that comprises a surgical cutting and fastening instrument of a type that may commonly be referred to as a “circular surgical stapler”. In certain types of surgical procedures, the use of surgical staples has become the preferred method of joining tissue and, as such, specially configured surgical staplers have been developed for these applications. For example, intra-luminal or circular staplers have been developed for use in surgical procedures involving the lower colon wherein sections of the lower colon are joined together after a diseased portion has been excised. Circular staplers useful for performing such procedures are disclosed, for example, in U.S. Pat. Nos. 5,104,025; 5,205,459; 5,285,945; 5,309,927; 8,353,439; and 8,360,297 which are each herein incorporated by reference in their respective entireties. 
     As shown in  FIG.  42   , the end effector  3000  comprises an end effector housing  3010  that may be fabricated from housing segments  3012 ,  3014  that are removably coupled together by screws, lugs, snap features, etc. Protruding from the end effector housing  3010  is an elongated shaft assembly  3020 . The elongated shaft assembly  3020  is configured to operably support and interact with a circular tool head  3300  and an anvil  3320 . As evidenced by the exemplary U.S. patents referenced above, a variety of different circular staple cartridge and anvil arrangements are known in the art. As shown in  FIG.  43   , for example, the circular stapler head  3300  may include a casing member  3302  that supports a cartridge supporting assembly in the form of a circular staple driver assembly  3304  therein that is adapted to interface with a circular staple cartridge  3306  and drive staples supported therein into forming contact with the staple forming undersurface  3326  of the anvil  3320 . A circular knife member  3308  is also centrally disposed within the staple driver assembly  3304 . The proximal end of the casing member  3302  may be coupled to an outer tubular shroud  3022  of the arcuate shaft assembly  3020  by a distal ferrule member  3024 . The anvil  3320  includes a circular body portion  3322  that has an anvil shaft  3324  for attaching a trocar thereto. The anvil body  3322  has a staple forming undersurface  3326  thereon and may also have a shroud  3328  attached to the distal end thereof. The anvil shaft  3324  may be further provided with a pair of trocar retaining clips or leaf-type springs  3330  that serve to releasably retain a trocar  3042  in retaining engagement with the anvil shaft  3324  as will be discussed in further detail below. 
     In one form, the shaft assembly  3020  includes a compression shaft  3030 , a distal compression shaft portion  3032 , and a tension band assembly  3040  that are operably supported within the outer tubular shroud  3022 . A trocar tip  3042  is attached to a distal end of the tension band assembly  3040  by fasteners  3041 . As is known, the trocar tip  3042  may be inserted into the anvil shaft  3324  of the anvil  3320  and retained in engagement by trocar retaining clips  3330 . 
     The surgical end effector  3000  further includes a closure system  3070  and a firing system  3100 . In at least one form, the closure system  3070  includes a closure nut assembly  3084  that is attached to the proximal end of the tension band  3040 . As can be seen in  FIGS.  42  and  43   , the closure nut assembly  3084  includes a proximal coupler member  3085  that is attached to the proximal end of the tension band  3040  by a fastener  3087 . The closure system  3070  further includes a threaded closure shaft  3080  that is in threaded engagement with the closure nut  3084 . The closure shaft  3080  defines a closure shaft axis CSA-CSA and has a female socket coupler  57  attached to its proximal end to facilitate coupling of the closure shaft  3080  with a male coupler  51  that is attached to a first drive shaft in a surgical instrument. Rotation of the closure shaft  3080  in a first direction will cause the closure nut  3084  to drive the tension band assembly  3040  in the distal direction “DD”. Rotation of the closure shaft  3080  in an opposite direction will likewise result in the proximal travel of the closure nut  3084  and the tension band assembly  3040 . 
     As can be seen in  FIG.  43   , the distal compression shaft portion  3032  is coupled to the staple driver assembly  3304 . Thus, axial movement of the compression shaft  3030  within the outer tubular shroud  3022  causes the staple driver assembly  3304  to move axially within the casing member  3302 . The axial travel of the compression shaft  3030  is controlled by the firing system  3100 . In one form, the firing system  3100  includes a threaded firing shaft  3102  that is in threaded engagement with a threaded firing nut  3110  that is attached to the proximal end of the compression shaft  3030 . The firing shaft  3102  defines a firing shaft axis FSA-FSA that is parallel with or substantially parallel with the closure shaft axis CSA-CSA. See, e.g.,  FIGS.  44  and  45   . The proximal end of the firing shaft  3102  has a female socket coupler  57  attached thereto to facilitate coupling of the firing shaft  3102  with a male coupler  51  that is attached to a second drive shaft in a surgical instrument. Activation of the second drive system of the surgical instrument in one rotary direction will rotate the firing shaft  3102  in a first direction to thereby drive the compression shaft  3030  in the distal direction “DD”. As the compression shaft  3030  moves in the distal direction “DD”, the circular staple driver assembly  3304  is driven distally to drive the surgical staples in the staple cartridge  3306  into forming contact with the underside  3326  of the anvil body  3322 . In addition, the circular knife member  3308  is driven through the tissue clamped between the anvil body  3322  and the staple cartridge  3306 . Actuation of the second drive system in a second rotary direction will cause the compression shaft  3030  to move in the proximal direction “PD”. 
     The end effector  3000  may also be equipped with various sensors that are coupled to an end effector contact board  3120  mounted within the end effector housing  3010 . For example, the end effector  3000  may include closure sensor(s)  3122  that are mounted within the end effector housing  3010  and are electrically coupled to the end effector contact board  3120  such that when the end effector  3000  is operably coupled to the surgical instrument, the closure sensor(s)  3122  are in communication with the surgical instrument&#39;s control system. The closure sensor(s)  3122  may comprise Hall effect sensors  7028  as described hereinbelow in connection with  FIGS.  61 ,  63 A,  63 B  that are configured to detect the position of the closure nut  3084 . See  FIG.  44   . In addition, firing sensor(s)  3124  may also be mounted within the end effector housing  3010  and be arranged to detect the location of the firing nut  3110  within the closure nut  3084 . The firing sensor(s)  3124  also may comprise Hall effect sensors  7028  as described hereinbelow in connection with  FIGS.  61 ,  63 A,  63 B  and be electrically coupled to the end effector contact board  3120  for ultimate communication with the surgical instrument control system, such as the handle processor  7024 , for example, as described in further below in connection with  FIGS.  61 ,  63 A,  63 B,  64   . The contact board  3120  may be positioned with the end effector housing  3020  such that when the end effector  3000  is operably coupled to the surgical instrument, the end effector contact board  3120  is electrically coupled to a surgical instrument contact board  30  mounted in the surgical instrument housing  12  as was discussed above. 
     Use of the end effector  3000  will now be explained in connection with surgical instrument  10 . It will be appreciated, however, that the end effector  3000  may be operably coupled to various other surgical instrument arrangements disclosed herein. Prior to use, the closure shaft  3080  and the firing shaft  3102  are “clocked” or positioned in their starting positions to facilitate attachment to the first and second drive shafts  22 ,  42 , respectively. To couple the end effector  3000  to the surgical instrument  10 , for example, the clinician moves the end effector  3000  into a position wherein the closure shaft axis CSA-CSA is in axial alignment with the first drive shaft axis FDA-FDA and wherein the firing shaft axis FSA-FSA is in axial alignment with the second drive shaft axis SDA-SDA. The female socket coupler  57  on the closure shaft  3080  is inserted into operable engagement with the male coupler  51  on the first drive shaft  22 . Likewise, the female socket coupler  57  on the firing shaft  3102  is inserted into operable engagement with the male coupler  51  on the second drive shaft  42 . Thus, when in that position, the closure shaft  3080  is operably coupled to the first drive shaft  22  and the firing shaft  3102  is operably coupled to the second drive shaft  42 . The end effector contact board  3120  is operably coupled to the surgical instrument contact board  30  so that the sensors  3122 ,  3124  within the end effector  3000  are in operable communication with the surgical instrument&#39;s control system. To retain the end effector  3000  in coupled operable engagement with the surgical instrument  10 , the end effector  3000  includes a retainer latch  3130  that is attached to the end effector housing  3010  and configured to releasably engage a portion of the instrument housing  12 . The retainer latch  3130  may include a retention lug  3132  that may releasable engage a retainer cavity  15  formed in the housing  12 . See  FIG.  1   . When coupled together, the closure sensor  3122  detects the position of the closure nut  3084  and the firing sensor  3124  detects the position of the firing nut  3110 . That information is communicated to the surgical instrument control system. In addition, the clinician may confirm that the shiftable transmission assembly (or the transmission carriage  62  thereof) is in its first drive position. This may be confirmed by the actuation of the indicator light  77  on the housing  12  as was discussed above. If the shiftable transmission assembly  60  is not in its first drive position, the clinician may actuate the firing trigger  92  to move the transmission carriage  62  into the first drive position, such that actuation of the rocker trigger  110  to actuate the motor  80  will result in actuation of the first drive system  20 . Assuming that the closure system  3070  and firing system  3100  are each in their respective starting positions and the end effector  3000  has an unspent staple cartridge module properly installed therein, the end effector  3000  is ready for use. 
     As is known, when performing an anastomosis using a circular stapler, the intestine may be stapled using a conventional surgical stapler with multiple rows of staples being emplaced on either side of a target section (i.e., specimen) of the intestine. The target section is typically simultaneously cut as the section is stapled. After removing the target specimen, the clinician inserts the anvil  3320  into the proximal portion of the intestine, proximal of the staple line. This may be done by inserting the anvil body  3322  into an entry port cut into the proximal intestine portion or the anvil  3320  can be placed trans-anally, by placing the anvil  3320  on the distal end of the end effector  3000  and inserting the instrument through the rectum. Next, the clinician attaches the anvil shaft  3324  to the trocar tip  3042  of the end effector  3000  and inserts the anvil  3320  into the distal portion of the intestine. The clinician may then tie the distal end of the proximal section of the intestine to the anvil shaft  3324  using a suture or other conventional tying device and also tie the proximal end of the distal intestine portion around the anvil shaft  3324  using another suture. 
     The clinician may then move the tension band assembly  3040 , trocar tip  3042  and anvil  3320  attached thereto proximally by actuating the rocker trigger  110  to actuate the motor  80  and rotate the first drive shaft  22 . This actuation moves the anvil  3320  toward the cartridge  3306  supported in the casing member  3302  of the stapler head  3300  to close the gap therebetween and thereby engages the proximal end of the distal intestine portion with the distal end of the proximal intestine portion in the gap therebetween. The clinician continues to actuate the first drive system  20  until a desired amount of tissue compression is attained. Once the intestine portions have been clamped between the anvil assembly  3320  and the stapler head  3300 , the clinician may then actuate the firing trigger  92  to move the transmission carriage  62  to its second drive position such that actuation of the motor  80  will result in the rotation of the second drive shaft  42 . Once the transmission carriage  62  is moved to the second drive position, the clinician may once again actuate the rocker trigger  110  to actuate the second drive system  40  and the firing system  3100  in the end effector  3000  to drive the compression shaft  3030  distally which also drives the circular staple driver assembly  3304  and the circular knife member  3308  distally. Such action serves to cut the clamped pieces of intestine and drive the surgical staples through both clamped ends of the intestine, thereby joining the portions of intestine and forming a tubular pathway. Simultaneously, as the staples are driven and formed, the circular knife  3308  is driven through the intestinal tissue ends, cutting the ends adjacent to the inner row of staples. The clinician may then withdraw the end effector  3000  from the intestine and the anastomosis is complete. 
       FIGS.  46 - 49    illustrate another surgical end effector  3000 ′ that may be identical to the surgical end effector  3000  described above except for the differences noted below. Those components of the surgical end effector  3000 ′ that are the same as the components in the surgical end effector  3000  described above will be designated with the same element numbers. Those components of surgical end effector  3000 ′ that may be similar in operation, but not identical to corresponding components of the surgical end effector  3000 , will be designated with the same component numbers along with a “′”. As can be seen in  FIGS.  46 - 49   , the surgical end effector  3000 ′ includes a drive disengagement assembly, generally designated as  3090 , that is advantageously configured to enable the clinician to disengage a distal portion of a drive train from a proximal portion of a drive train. 
     In the depicted embodiment, the drive disengagement assembly  3090  is used in connection with the closure system  3070 ′ so that in the event that the distal portion of the closure system becomes inadvertently jammed or otherwise disabled, the clinician may quickly mechanically separate the distal drive train portion from the proximal drive train portion of the closure system. More specifically and with reference to  FIG.  47   , the tension band assembly  3040  and the trocar tip  3042  (See  FIGS.  42 ,  43  and  45   ) may also be referred to as the “distal drive train portion”  3092  of the closure system  3070 ′ and the closure shaft  3080  and closure nut assembly  3084  may, for example, be referred to as the “proximal drive train portion”  3094  of the closure system  3070 ′. As can be seen in  FIG.  47   , one form of the drive disengagement assembly  3090  includes a distal coupler member  3095  that is attached to a proximal end of the tension band assembly  3040 . The distal coupler member  3095  may be attached to the tension band assembly  3040  by press fit, adhesive, solder, welding, etc. or any combination of such attachment arrangements. The distal coupler member  3095  is sized to be slidable received within a slot  3097  in the proximal coupler member  3085 ′ that is attached to the closure nut assembly  3084 . The distal coupler member  3095  includes a distal hole  3096  therethrough that is configured to axially register with a proximal hole  3098  in the proximal coupler member  3085 ′ when the distal coupler member  3095  is seated within the slot  3097 . See  FIG.  48   . The drive disengagement assembly  3090  further comprises a drive coupler pin  3099  that is sized to be received within the axially aligned holes  3096 ,  3098  to retainingly couple the distal coupler member  3095  to the proximal coupler member  3085 ′. Stated another way, the drive coupler pin  3099  serves to mechanically and releasably couple the distal drive train portion  3092  to the proximal drive train portion  3094 . The drive coupler pin  3099  extends along a coupling axis CA-CA that is transverse to the closure shaft axis CSA. To provide clearance for the drive coupler pin  3099  to move axially relative to the firing nut  3110 , an axial slot  3111  is provided in the firing nut  3110 . As can be seen in  FIG.  46   , the end effector housing portion  3014 ′ is provided with an axially extending clearance slot  3016  to facilitate axial travel of the drive coupler pin  3099  during the actuation of the closure system  3070 ′. Such arrangement enables the clinician to quickly decouple the distal drive train portion  3092  from the proximal drive train portion  3094  at any time during use of the end effector  3000 ′ simply by removing or pulling the drive coupler pin  3099  transversely out of the holes  3096 ,  3098  to permit the distal coupler member  3095  to be disengaged from the proximal coupler member  3085 ′. 
     While the drive disengagement assembly  3090  has been described in connection with the closure system  3070 ′ of the end effector  3000 ′, the drive disengagement assembly could, in the alternative, be employed in connection with the firing system  3100  of the end effector  3000 ′. In other arrangements, a drive disengagement assembly  3090  could be associated with the closure system and a second drive disengagement assembly may be associated with the firing system. Thus, one or both of the proximal drive train portions may be selectively mechanically separated from their respective distal drive train portions. Further, such drive disengagement assembly may be effectively employed in connection with the closure and/or firing systems of at least some of other surgical end effectors disclosed herein including but not necessarily limited to, for example, end effector  1000  and end effector  2000  and their respective equivalent arrangements. 
       FIGS.  50 - 53    illustrate another surgical end effector  2000 ′ that may be identical to the surgical end effector  2000  described above except for the differences noted below. Those components of the surgical end effector  2000 ′ that are the same as the components in the surgical end effector  2000  described above will be designated with the same element numbers. Those components of surgical end effector  2000 ′ that may be similar in operation, but not identical to corresponding components of the surgical end effector  2000 , will be designated with the same component numbers along with a “′”. As can be seen in  FIGS.  51 - 53   , the surgical end effector  2000 ′ may be provided with indicator arrangements for providing a visual indication as to the firing status of the closure and firing systems. 
     More particularly and with reference to  FIGS.  51  and  52   , the closure system  2070  includes a closure system status assembly, generally designated as  2090 . In one form, for example, the closure system status assembly  2090  includes a closure indicator member  2092  that is attached to or otherwise extends from the closure nut  2084 ′. The closure system status assembly  2090  further includes a closure indicator window  2094  or opening in the end effector housing  2010  such that the position of the closure indicator member  2092  may be assessed by the clinician by viewing the closure indicator member  2092  through the closure indicator window  2094 . Similarly, the firing system  2100 ′ may include a firing system status assembly, generally designated as  2130 . In one form, for example, the firing system status assembly  2130  includes a firing indicator member  2132  that is attached to or otherwise extends from the firing nut  2110 ′. The firing system status assembly  2130  further includes a firing indicator window or opening  2134  in the end effector housing  2010  such that the position of the firing indicator member  2132  may be assessed by the clinician by viewing the firing indicator member  2132  through the firing indicator window  2134 . 
     The closure system status assembly  2090  and the firing system status assembly  2130  reveal the mechanical state of the closure system  2070  and the firing system  2100 . The mechanical state of the distal end of the end effector can generally be observed by the clinician, but it sometimes is covered or obstructed by tissue. The mechanical state of the proximal portion of the end effector cannot be seen without a window arrangement or protruding indicator. Color coding on the exterior of the shaft arrangement and or on the indicator may also be employed to provide the clinician confirmation that the end effector has been fully closed or fired (e.g., indicator on green for fully closed). For example, the closure indicator member  2092  may have a closure mark  2093  thereon that is viewable through the closure indicator window  2094 . In addition, the housing  2010  may have a first closure indicia  2095  and a second closure indicia  2096  adjacent to the closure indicator window  2094  to assess the position of the closure indicator  2092 . For example, the first closure indicia  2095  may comprise a first bar that has a first color (e.g., range, red, etc.) and the second closure indicia may comprise a bar or section of a second color that differs from the first color (e.g., green). When the closure mark  2093  on the closure indicator member  2092  is aligned on the proximal-most end of the first closure indicia bar  2095  (this position is represented by element number  2097  in  FIG.  50   ), the clinician can observe that the closure system  2070  is in its unactuated position. When the closure mark  2093  is aligned within the first closure indicia bar  2095 , the clinician can observe that the closure system  2070  is partially actuated—but not fully actuated or fully closed. When the closure mark  2093  is aligned with the second closure indicia  2096  (represented by element number  2098  in  FIG.  50   ), the clinician can observe that the closure system  2070  is in its fully actuated or fully closed position. 
     Similarly, the firing indicator member  2132  may have a firing mark  2133  thereon that is viewable through the firing indicator window  2134 . In addition, the housing segment  2014 ′ may have a first firing indicia  2135  and a second firing indicia  2136  adjacent to the firing indicator window  2134  to assess the position of the firing indicator  2132 . For example, the first firing indicia  2135  may comprise a first firing bar that has a first firing color (e.g., orange, red, etc.) and the second firing indicia may comprise a second firing bar or section of a second firing color that differs from the first firing color (e.g., green). When the firing mark  2133  on the firing indicator member  2132  is aligned on the proximal-most end of the first firing indicia bar  2135  (this position is represented by element number  2137  in  FIG.  50   ), the clinician can observe that the firing system  2100  is in its unactuated position. When the firing mark  2133  is aligned within the first firing indicia bar  2135 , the clinician can observe that the firing system  2100  is partially actuated—but not fully actuated or fully fired. When the firing mark  2133  is aligned with the second firing indicia  2136  (represented by element number  2138  in  FIG.  50   ), the clinician can observe that the firing system  2170  is in its fully actuated or fully fired position. Thus, the clinician may determine the extent to which the closure and firing systems have been actuated by observing the position of the indicators within their respective windows. 
     In alternative arrangement, the indicator windows  2094  and  2134  may be provided in the end effector housing  2010 ′ such that when the closure system  2070  and firing system  2100 ′ are in their starting or unactuated positions, their respective indicators  2092 ,  2132  may be in full view in the indicator windows  2094 ,  2134 , respectively. As the closure system  2070  and firing system  2100 ′ are actuated, their indicators  2092 ,  2132  will move out of their indicator windows  2094 ,  2134 . The clinician may then assess how far each of the systems  2070 ,  2100 ′ have been actuated by observing how much of the indicators  2092 ,  2132  are viewable through the windows  2094 ,  2134 . 
     The closure system status assembly  2090  and the firing system status assembly  2130  reveal the mechanical state of the closure system  2070  and the firing system  2100  whether the end effector  2000 ′ is attached to the surgical instrument handle or housing or not. When the end effector  2000  is attached to the handle or housing, the closure system status assembly  2090  and the firing system status assembly  2130  will afford the clinician with the opportunity to determine the mechanical states of those systems as a primary or secondary check to the state shown on the surgical instrument handle or housing. The closure system status assembly  2090  and the firing system status assembly  2130  also serve as a primary check when the end effector  2000 ′ is detached from the surgical instrument handle or housing. Further, such closure system and firing system status assemblies may be effectively employed in connection with the closure and/or firing systems of at least some of other surgical end effectors disclosed herein including but not necessarily limited to, for example, end effector  1000  and end effector  3000  and their respective equivalent arrangements. 
       FIGS.  54 - 60    illustrate another surgical end effector  2000 ″ that may be identical to the surgical end effector  2000 ′ described above except for the differences noted below. Those components of the surgical end effector  2000 ″ that are the same as the components in the surgical end effector  2000 ′ and/or end effector  2000  described above will be designated with the same element numbers. Those components of surgical end effector  2000 ″ that may be similar in operation, but not identical to corresponding components of the surgical end effector  2000 ′ and/or  2000 , will be designated with the same component numbers along with a “″”. As can be seen in  FIGS.  54 - 60   , the surgical end effector  2000 ″ includes a drive disengagement assembly, generally designated as  2200 , that is advantageously configured to enable the clinician to disengage a distal portion of a drive train from a proximal portion of a drive train. 
     In the depicted embodiment, the drive disengagement assembly  2200  is used in connection with the closure system  2070 ″ of the end effector  2000 ″ so that in the event that the distal portion of the closure system becomes inadvertently jammed or otherwise disabled, the clinician may quickly mechanically separate the distal drive train portion from the proximal drive train portion of the closure system. More specifically and with reference to  FIG.  56   , the closure beam assembly  2072  may also be referred to as the “distal drive train portion”  2202  of the closure system  2070 ″ and the closure shaft  2080  and closure nut assembly  2084 ″ may, for example, be referred to as the “proximal drive train portion”  2204  of the closure system  2070 ″. As can be seen in  FIG.  59   , the closure nut assembly  2084 ″, while substantially identical to closure nut assemblies  2084 ,  2084 ′ described above, is provided in two parts. More specifically, closure nut assembly  2084 ″ includes an upper threaded portion  2210  that is in threaded engagement with the closure shaft  2080  and a lower portion  2214  that supports the firing nut  2110  for axial movement therein in the manner discussed above. The lower portion  2214  of the closure nut assembly  2084 ″ is directly attached to the closure beam assembly  2072  and includes the closure indicator member  2092 ″ that functions in the same manner as closure indicator  2092  discussed above. 
     In at least one form, the drive disengagement assembly  2200  includes a drive coupler pin  2220  that serves to couple the lower portion  2214  of the closure nut assembly  2084 ″ to the upper portion  2210 . As can be seen in  FIG.  59   , for example, the upper portion  2210  of the closure nut assembly  2084 ″ includes a first dovetail slot segment  2212  that is configured for alignment with a second dovetail slot segment  2216  in the lower portion  2214  of the closure nut assembly  2084 ″. When the first and second dovetail slot segments  2212 ,  2216  are aligned as shown in  FIG.  59   , they form hole  2215  into which the barrel portion  2222  of the drive coupler pin  2220  may be inserted to couple the upper and lower portions  2010  and  2014  together as shown in  FIG.  56   . Stated another way, the drive coupler pin  2220  serves to mechanically and releasably couple the distal drive train portion  2202  to the proximal drive train portion  2204  of the closure system  2070 ″. The drive coupler pin  2220  extends along a coupling axis CA-CA that is transverse to the closure shaft axis CSA. See  FIG.  56   . To provide clearance for the drive coupler pin  2220  to move axially with the closure nut assembly  2084 ″, the housing segment  2014 ″ of the end effector housing  2010 ″ is provided with an axially extending clearance slot  2224 . Such arrangement enables the clinician to quickly decouple the distal drive train portion  2202  from the proximal drive train portion  2204  at any time during use of the end effector  2000 ″ simply by removing or pulling the drive coupler pin  2220  transversely out of the hole  2215  formed by the dovetail slot segments  2212 ,  2216 . Once the drive coupler pin  2220  has been removed from the hole  2215 , the lower portion  2214  of the closure assembly  2084 ″ can be moved relative to the upper portion  2212  to thereby enable the tissue to be released from between the cartridge module  2060  and the anvil assembly  2140 . 
       FIGS.  54 - 56    depict the end effector  2000 ″ in an “open” position prior to use. As can be seen in those Figures, for example, a cartridge module  2060  is installed and ready for use.  FIGS.  57  and  58    depict the end effector  2000  in its closed state. That is, the closure beam  2080  has been rotated to drive the closure nut assembly  2084 ″ in the distal direction “DD”. Because the lower portion  2214  of the closure nut assembly  2084 ″ is attached to the upper portion  2210  by the drive coupler pin  2220 , the closure beam assembly  2072  (because it is attached to the lower portion  2214 ) is also moved distally to its closed position to clamp target tissue between the cartridge module  2260  and the anvil assembly  2140 . As was also discussed above, the saddle shaped slide button  2162  on the housing  2010 ″ is moved distally to cause the retaining pin to extend through the cartridge housing and into the anvil assembly  2140  to thereby capture the tissue between the cartridge module  2060  and the anvil assembly  2140 . As was discussed in detail above, when the closure nut assembly  2084 ″ moves distally, the firing nut  2110  also moves distally which draws the proximal portion  2106  of the firing shaft  2102  out of the elongated passage within the female socket coupler  57 ′. See  FIG.  58   .  FIG.  59    illustrates the drive coupler pin  2220  removed from the hole  2215  formed by the dovetail slot segments  2212 ,  2216 . Once the drive coupler pin  2220  has been removed from the hole  2215 , the proximal drive train portion  2202  (closure beam assembly  2072 ) may be moved in the proximal direction “PD” by moving the saddle shaped slide button  2162  proximally. Such movement of the button  2162  will move the closure beam assembly  2072 , the lower portion  2014  of the closure nut assembly  2084 ″, the firing nut  2110  and firing bar assembly  2112 , as well as the retaining pin proximally. Such movement will enable the tissue to be released from between the cartridge module  2060  and the anvil assembly  2140 . 
       FIG.  61    is a block diagram of a modular motor driven surgical instrument  7000  comprising a handle portion  7002  and a shaft portion  7004 . The modular motor driven surgical instrument  7000  is representative of the modular surgical instrument system generally designated as  2  that, in one form, includes a motor driven surgical instrument  10  that may be used in connection with a variety of surgical end effectors such as, for example, end effectors  1000 ,  2000  and  3000  as shown in  FIG.  1   . Having described various functional and operational aspects of the modular motor driven surgical instrument  10  in detail hereinabove, for conciseness and clarity of disclosure such details will not be repeated in the following description associated with  FIGS.  61 - 64   . Rather, the description of  FIGS.  61 - 64    that follows will focus primarily on the functional and operational aspects of the electrical systems and subsystems of the modular motor driven surgical instrument  7000 , which can be applied in whole or in part to the modular motor driven surgical instrument described hereinabove. 
     Accordingly, turning now to  FIG.  61    the modular motor driven surgical instrument  7000  comprises a handle portion  7002  and a shaft portion  7004 . The handle and shaft portions  7002 ,  7004  comprise respective electrical subsystems  7006 ,  7008  electrically coupled by a communications and power interface  7010 . The components of the electrical subsystem  7006  of the handle portion  7002  are supported by the previously described control board  100 . The communications and power interface  7010  is configured such that electrical signals and power can be readily exchanged between the handle portion  7002  and the shaft portion  7004 . 
     In the illustrated example, the electrical subsystem  7006  of the handle portion  7002  is electrically coupled to various electrical elements  7012  and a display  7014 . In one instance, the display  7014  is an organic light emitting diode (OLED) display, although the display  7014  should not be limited in this context. The electrical subsystem  7008  of the shaft portion  7004  is electrically coupled to various electrical elements  7016 , which will be described in detail hereinbelow. 
     In one aspect, the electrical subsystem  7006  of the handle portion  7002  comprises a solenoid driver  7018 , an accelerometer  7020 , a motor controller/driver  7022 , a handle processor  7024 , a voltage regulator  7026 , and is configured to receive inputs from a plurality of switches  7028 . Although, in the illustrated embodiment, the switches  7028  are designated as Hall switches, the switches  7028  are not limited in this context. In various aspects, the Hall effect sensors or switches  7028  may be located either in the end effector portion of the instrument, the shaft, and/or the handle. 
     In one aspect, the electrical subsystem  7006  of the handle portion  7002  is configured to receive signals from a solenoid  7032 , a clamp position switch  7034 , a fire position switch  7036 , a motor  7038 , a battery  7040 , an OLED interface board  7042 , and open switch  7044 , close switch  7046 , and fire switch  7048 . In one aspect, the motor  7038  is a brushless DC motor, although in various aspects the motor is not limited in this context. Nevertheless, the description of the motor  7038  may be applicable to the motors  80 ,  480 ,  580 ,  680 ,  750 , and  780  previously described. The solenoid  7032  is representative example of the previously described shifter solenoid  71 . 
     In one aspect, the electrical subsystem  7008  of the shaft portion  7004  comprises a shaft processor  7030 . The electrical subsystem  7008  of the shaft is configured to receive signals from various switches and sensors located in the end effector portion of the instrument that are indicative of the status of the clamp jaws and cutting element in the end effector. As illustrated in  FIG.  61   , the electrical subsystem  7008  of the shaft is configured to receive signals from a clamp opened status switch  7050 , a clamp closed status switch  7052 , a fire begin status switch  7054 , and a fire end status switch  7056 , which are indicative of the states of the clamp and cutting element. 
     In one aspect, the handle processor  7024  may be a general purpose microcontroller suitable for medical and surgical instrument applications and including motion control. In one instance, the handle processor  7024  may be a TM4C123BH6ZRB microcontroller provided by Texas Instruments. The handle processor  7024  may comprise a 32-bit ARM® Cortex™-M4 80-MHz processor core with System Timer (SysTick), integrated nested vectored interrupt controller (NVIC), wake-up interrupt controller (WIC) with clock gating, memory protection unit (MPU), IEEE754-compliant single-precision floating-point unit (FPU), embedded trace macro and trace port, system control block (SCB) and thumb-2 instruction set, among other features. The handle processor  7024  may comprise on-chip memory, such as 256 KB single-cycle Flash up to 40 MHz. A prefetch buffer can be provided to improve performance above 40 MHz. Additional memory includes a 32 KB single-cycle SRAM, internal ROM loaded with TivaWare™ for C Series software, 2 KB EEPROM, among other features, such as two Controller Area Network (CAN) modules, using CAN protocol version 2.0 part A/B and with bit rates up to 1 Mbps. 
     In one aspect, the handle processor  7024  also may comprise advanced serial integration including eight universal asynchronous receiver/transmitters (UARTs) with IrDA, 9-bit, and ISO 7816 support (one UART with modem status and modem flow control). Four Synchronous Serial Interface (SSI) modules are provided to support operation for Freescale SPI, MICROWIRE or Texas Instruments synchronous serial interfaces. Additionally, six Inter-Integrated Circuit (I2C) modules provide Standard (100 Kbps) and Fast (400 Kbps) transmission and support for sending and receiving data as either a master or a slave, for example. 
     In one aspect, the handle processor  7024  also comprises an ARM PrimeCell® 32-channel configurable μDMA controller, providing a way to offload data transfer tasks from the Cortex™-M4 processor, allowing for more efficient use of the processor and the available bus bandwidth. Analog support functionality includes two 12-bit Analog-to-Digital Converters (ADC) with 24 analog input channels and a sample rate of one million samples/second, three analog comparators, 16 digital comparators, and an on-chip voltage regulator, for example. 
     In one aspect, the handle processor  7024  also comprises advanced motion control functionality such as eight Pulse Width Modulation (PWM) generator blocks, each with one 16-bit counter, two PWM comparators, a PWM signal generator, a dead-band generator, and an interrupt/ADC-trigger selector. Eight PWM fault inputs are provided to promote low-latency shutdown. Two quadrature encoder interface (QEI) modules are provided, with a position integrator to track encoder position and velocity capture using built-in timer. 
     In one aspect, two ARM FiRM-compliant watchdog timers are provided along with six 32-bit general-purpose timers (up to twelve 16-bit). Six wide 64-bit general-purpose timers (up to twelve 32-bit) are provided as well as 12 16/32-bit and 12 32/64-bit capture compare PWM (CCP) pins, for example. Up to 120 general purpose input/outputs (GPIOs) can be provided depending on configuration, with programmable control for GPIO interrupts and pad configuration, and highly flexible pin multiplexing. The handle processor  7024  also comprises lower-power battery-backed hibernation module with real-time clock. Multiple clock sources are provided for the microcontroller system clock and include a precision oscillator (PIOSC), main oscillator (MOSC), 32.768-kHz external oscillator for the hibernation module, and an internal 30-kHz oscillator. 
     In one aspect, the accelerometer  7020  portion of the electrical subsystem  7006  of the handle portion  7002  may be a micro-electromechanical system (MEMS) based motion sensor. As is well known, MEMS technology combines computers with tiny mechanical devices such as sensors, valves, gears, mirrors, and actuators embedded in semiconductor chips. In one example, the MEMS based accelerometer  7020  may comprise an ultra low power 8 bit 3-axis digital accelerometer such as the LIS331DLM provided by STMicroelectronics, for example. 
     In one aspect, the accelerometer  7020 , such as the LIS331DLM, may be an ultra low-power high performance three axes linear accelerometer belonging to the “nano” family, with digital I2C/SPI serial interface standard output, with is suitable for communicating with the handle processor  7024 . The accelerometer  7020  may feature ultra low-power operational modes that allow advanced power saving and smart sleep to wake-up functions. The accelerometer  7020  may include dynamically user selectable full scales of ±2 g/±4 g/±8 g and it is capable of measuring accelerations with output data rates from 0.5 Hz to 400 Hz, for example. 
     In one aspect, the accelerometer  7020  may include self-test capability to allow the user to check the functioning of the sensor in the final application. The accelerometer  7020  may be configured to generate an interrupt signal by inertial wake-up/free-fall events as well as by the position of the instrument itself. Thresholds and timing of interrupt generators may be programmable on the fly. 
     In one aspect, the motor controller/driver  7022  may comprise a three phase brushless DC (BLDC) controller and MOSFET driver, such as the A3930 motor controller/driver provided by Allegro, for example. The 3-phase brushless DC motor controller/driver  7022  may be employed with N-channel external power MOSFETs to drive the BLDC motor  7038 , for example. In one instance, the motor controller/driver  7022  may incorporate circuitry required for an effective three-phase motor drive system. In one instance, the motor controller/driver  7022  comprises a charge pump regulator to provide adequate (&gt;10 V) gate drive for battery voltages down to 7 V, and enables the motor controller/driver  7022  to operate with a reduced gate drive at battery voltages down to 5.5 V. Power dissipation in the charge pump can be minimized by switching from a voltage doubling mode at low supply voltage to a dropout mode at the nominal running voltage of 14 V. In one aspect, a bootstrap capacitor is used to provide the above-battery supply voltage required for N-channel MOSFETs. An internal charge pump for the high-side drive allows for dc (100% duty cycle) operation. 
     An internal fixed-frequency PWM current control circuitry regulates the maximum load current. The peak load current limit may be set by the selection of an input reference voltage and external sensing resistor. The PWM frequency can be set by a user-selected external RC timing network. For added flexibility, the PWM input can be used to provide speed and torque control, allowing the internal current control circuit to set the maximum current limit. 
     The efficiency of the motor controller/driver  7022  may be enhanced by using synchronous rectification. The power MOSFETs are protected from shoot-through by integrated crossover control with dead time. The dead time can be set by a single external resistor. 
     In one aspect, the motor controller/driver  7022  indicates a logic fault in response to the all-zero combination on the Hall inputs. Additional features of the motor controller/driver  7022  include high current 3-phase gate drive for N-channel MOSFETs, synchronous rectification, cross-conduction protection, charge pump and top-off charge pump for 100% PWM, integrated commutation decoder logic, operation over 5.5 to 50 V supply voltage range, diagnostics output, provides +5 V Hall sensor power, and has a low-current sleep mode. 
     In one aspect, the modular motor driven surgical instrument  7000  is equipped with a brushless DC electric motor  7038  (BLDC motors, BL motors) also known as electronically commutated motors (ECMs, EC motors). One such motor is the BLDC Motor B0610H4314 provided by Portescap. The BLDC Motor B0610H4314 can be autoclavable. The BLDC motor  7038  is a synchronous motor that is powered by a DC electric source via an integrated inverter/switching power supply, which produces an AC electric signal to drive the motor such as the motor controller/driver  7022  described in the immediately foregoing paragraphs. In this context, AC, alternating current, does not imply a sinusoidal waveform, but rather a bi-directional current with no restriction on waveform. Additional sensors and electronics control the inverter output amplitude and waveform (and therefore percent of DC bus usage/efficiency) and frequency (i.e., rotor speed). 
     The rotor part of the BLDC motor  7038  is a permanent magnet synchronous motor, but in other aspects, BLDC motors can also be switched reluctance motors, or induction motors. Although some brushless DC motors may be described as stepper motors, the term stepper motor tends to be used for motors that are designed specifically to be operated in a mode where they are frequently stopped with the rotor in a defined angular position. 
     In one aspect, the BLDC motor controller/driver  7022  must direct the rotation of the rotor. Accordingly, the BLDC motor controller/driver  7022  requires some means of determining the rotor&#39;s orientation/position (relative to the stator coils.) In one instance, the rotor part of the BLDC motor  7038  is configured with Hall effect sensors or a rotary encoder to directly measure the position of the rotor. Others measure the back electromotive force (EMF) in the undriven coils to infer the rotor position, eliminating the need for separate Hall effect sensors, and therefore are often called sensorless controllers. 
     In one aspect, the BLDC motor controller/driver  7022  contains 3 bi-directional outputs (i.e., frequency controlled three phase output), which are controlled by a logic circuit. Other, simpler controllers may employ comparators to determine when the output phase should be advanced, while more advanced controllers employ a microcontroller to manage acceleration, control speed and fine-tune efficiency. 
     Actuators that produce linear motion are called linear motors. The advantage of linear motors is that they can produce linear motion without the need of a transmission system, such as a ball-and-lead screw, rack-and-pinion, cam, gears or belts that would be necessary for rotary motors. Transmission systems are known to introduce less responsiveness and reduced accuracy. The direct drive, BLDC motor  7038  may comprise a slotted stator with magnetic teeth and a moving actuator, which has permanent magnets and coil windings. To obtain linear motion, the BLDC motor controller/driver  7022  excites the coil windings in the actuator causing an interaction of the magnetic fields resulting in linear motion. 
     In one aspect, the BLDC motor  7038  is a Portescap BO610 brushless DC motor that provides a combination of durability, efficiency, torque, and speed in a package suitable for use in the modular motor driven surgical instrument  7000 . Such BLDC motors  7038  provide suitable torque density, speed, position control, and long life. The slotless BLDC motor  7038  uses a cylindrical ironless coil made in the same winding technique as ironless DC motors. The slotted BLDC motors  7038  also are autoclavable. The slotted BLDC motor  7038  may include a stator that consists of stacked steel laminations with windings placed in the slots that are axially cut along the inner periphery. The brushless DC slotted BLDC motor  7038  provides high torque density and heat dissipation, along with high acceleration. The three-phase configuration of the BLDC motor  7038  includes Wye connections, Hall effect sensors, supply voltage of 4.5-24V. The housing of the BLDC motor  7038  may be made of a 303SS material and the shaft may be made of a 17-4 ph material. 
     In one aspect, the Hall switches  7028  may be Hall effect sensors known under the trade name BU520245G and are unipolar integrated circuit type Hall effect sensors. These sensors operate over a supply voltage range of 2.4V to 3.6V. 
     In one aspect, the voltage regulator  7026  replaces the usual PNP pass transistor with a PMOS pass element. Because the PMOS pass element behaves as a low-value resistor, the low dropout voltage, typically 415 mV at 50 A of load current, is directly proportional to the load current. The low quiescent current (3.2 μA typically) is stable over the entire range of output load current (0 mA to 50 mA). 
     In one aspect, the voltage regulator  7026  is a low-dropout (LDO) voltage regulator such as the TPS71533 LDO voltage regulator provided by Texas Instruments. Such LDO voltage regulators  7026  provide the benefits of high input voltage, low-dropout voltage, low-power operation, and miniaturized packaging. The voltage regulator  7026  can operate over an input range of 2.5 V to 24 V, are stable with any capacitor (≥0.47 μF). The LDO voltage and low quiescent current allow operations at extremely low power levels and thus the voltage regulator  7026  is suitable for powering battery management integrated circuits. Specifically, the voltage regulator  7026  is enabled as soon as the applied voltage reaches the minimum input voltage and the output is quickly available to power continuously operating battery charging integrated circuits of the handle portion  7002 . 
     In one aspect, the battery  7040  is a lithium-ion polymer (LIPO) battery, polymer lithium ion or more commonly lithium polymer batteries (abbreviated Li-poly, Li-Pol, LiPo, LIP, PLI or LiP) are rechargeable (secondary cell) batteries. The LIPO battery  7040  may comprise several identical secondary cells in parallel to increase the discharge current capability, and are often available in series “packs” to increase the total available voltage. 
     Additional power for the modular motor driven surgical instrument  7000  may be provided by a synchronous step down DC-DC converter  7058  ( FIG.  63 A ) optimized for applications with high power density such as the TPS6217X family provided by Texas Instruments. A high switching frequency of typically 2.25 MHz may be employed to allow the use of small inductors and provides fast transient response as well as high output voltage accuracy by utilization of the DCS-Control™ topology. 
     With a wide operating input voltage range of 3V to 17V, the synchronous step down DC-DC converter  7058  ( FIG.  63 A ) is well suited for modular motor driven surgical instrument  7000  systems powered from either a Li-Ion or other battery as well as from 12V intermediate power rails. In one aspect, a synchronous step down DC-DC converter  7058  supports up to 0.5 A continuous output current at output voltages between 0.9V and 6V (with 100% duty cycle mode). 
     Power sequencing is also possible by configuring the Enable and open-drain Power Good pins. In Power Save Mode, the synchronous step down DC-DC converter  7058  ( FIG.  63 A ) show quiescent current of about 17 μA from VIN. Power Save Mode is entered automatically and seamlessly if load is small and maintains high efficiency over the entire load range. In Shutdown Mode, the synchronous step down DC-DC converter  7058  is turned off and shutdown current consumption is less than 2 μA. 
     In one aspect, the OLED interface  7042  is an interface to the OLED display  7014 . The OLED display  7014  comprises organic light-emitting diodes in which the emissive electroluminescent layer is a film of organic compound which emits light in response to an electric current. This layer of organic semiconductor is situated between two electrodes, where in general at least one of these electrodes is transparent. The OLED display  7014  may include OLEDs from two main families. Those based on small molecules and those employing polymers. Adding mobile ions to an OLED creates a light-emitting electrochemical cell or LEC, which has a slightly different mode of operation. The OLED display  7014  can use either passive-matrix (PMOLED) or active-matrix addressing schemes. Active-matrix OLEDs (AMOLED) require a thin-film transistor backplane to switch each individual pixel on or off, but allow for higher resolution and larger display sizes. In one instance, the OLED display  7014  works without a backlight. Thus, it can display deep black levels and can be thinner and lighter than a liquid crystal display (LCD), making it ideally suitable for use on the handle portion  7002  of the modular motor driven surgical instrument  7000 . 
     In one aspect, the shaft processor  7030  of the electrical subsystem  7008  of the shaft portion  7004  may be implemented as an ultra-low power 16-bit mixed signal MCU, such as the MSP430FR5738 Ultra-low Power MCU provided by Texas Instruments. The shaft processor  7030  is an ultra-low power microcontroller consisting of multiple devices featuring embedded FRAM nonvolatile memory, ultra-low power 16-bit MSP430 CPU, and additional peripherals targeted for various applications. The architecture, FRAM, and peripherals, combined with seven low-power modes, are optimized to achieve extended battery life in portable and wireless sensing applications. FRAM is a new nonvolatile memory that combines the speed, flexibility, and endurance of SRAM with the stability and reliability of flash, all at lower total power consumption. Peripherals include 10-bit A/D converter, 16-channel comparator with voltage reference generation and hysteresis capabilities, three enhanced serial channels capable of I2C, SPI, or UART protocols, internal DMA, hardware multiplier, real-time clock, five 16-bit timers, among other features. 
     The shaft processor  7030  includes a 16-bit RISC architecture up to 24 MHz clock and operates over a wide supply voltage range of 2 V to 3.6 V and is optimized for ultra-low power modes. The shaft processor  7030  also includes intelligent digital peripherals, an ultra-low power ferroelectric RAM, and up to 16 KB of nonvolatile memory. The embedded microcontroller provides ultra-low power writes, a fast write cycle of 125 ns per word, 16 KB in 1 ms, and includes built in Error Coding and Correction (ECC) and Memory Protection Unit (MPU). 
     Having described the electrical system, subsystems, and components of the handle and shaft portions  7002 ,  7004  of the modular motor driven surgical instrument  7000 , the functional aspects of the control system will now be described. Accordingly, in operation, the electrical subsystem  7006  of the handle portion  7002  is configured to receive signals from the open switch  7044 , close switch  7046 , and fire switch  7048  supported on a housing of the handle portion  7002 . When a signal is received from the close switch  7046  the handle processor  7024  operates the motor  7038  to initiate closing the clamp arm. Once the clamp is closed, the clamp closed status switch  7052  in the end effector sends a signal to the shaft processor  7030 , which communicates the status of the clamp arm to the handle processor  7024  through the communications and power interface  7010 . 
     Once the target tissue has been clamped, the fire switch  7048  may be actuated to generate a signal, which is received by the handle processor  7024 . In response, the handle processor  7024  actuates the transmission carriage to its second drive position such that actuation of the motor  7038  will result in the rotation of a second drive shaft, as described in detail above in connection with  FIGS.  1 - 8   . Once the cutting member is positioned, the fire begin status switch  7054  located in the end effector sends a signal indicative of the position of the cutting member to the shaft processor  7030 , which communicates the position back to the handle processor  7024  through the communications and power interface  7010 . 
     Actuating the first switch  7048  once again sends a signal to the handle processor  7038 , which in response actuates the second drive system and the firing system in the end effector to drive the tissue cutting member and wedge sled assembly distally through the surgical staple cartridge. Once the tissue cutting member and wedge sled assembly have been driven to their distal-most positions in the surgical staple cartridge, the fire end switch  7056  sends a signal to the shaft processor  7030  which communicates the position back to the handle processor  7024  through the interface  7010 . Now the fire switch  7048  may be activated to send a signal to the handle processor  7024 , which operated the motor  7038  in reverse rotation to return the firing system to its starting position. 
     Actuating the open switch  7044  once again sends a signal to the handle processor  7024 , which operates the motor  7038  to open the clamp. Once open, the clamp opened status switch  7050  located in the end effector sends a signal to the shaft processor  7030 , which communicates the position of the clamp to the handle processor  7024 . The clamp position switch  7034  and the fire position switch  7036  provide signals to the handle processor  7024  that indicate the respective positions of the clamp arm and the cutting member. 
       FIG.  62    is a table  7060  depicting the total time it takes to complete a stroke and the load current requirements for various operations of various device shafts. The first column  7062  from the left lists circular, contour, and TLC devices/shafts. These devices/shafts are compared over three different operations closing, opening, and firing as shown in the second column  7064 . The third column  7066  depicts the total time in seconds required for the device/shaft listed in the first column  7063  to complete one stroke. The fourth column  7068  lists the load current requirements in amperes for the devices/shafts listed in the first column  7062  to complete the operation in the second column  7064  for a complete stroke as indicated in the third column  7066 . As indicated in the chart, closing and opening the clamp arm takes about the same time for each of the device/shafts listed in the first column  7062 . For the firing operation, the circular device/shaft requires the most load current at 15.69 A and the TLC device/shaft requires the least amount load current at 0.69 A. 
       FIG.  63 A  is a detail diagram of the electrical system in the handle portion  7002  of the modular motor driven surgical instrument  7000 . As shown in  FIG.  63 A , the voltage regulator  7026  and DC-DC converter  7058  provide the operating voltages for the electrical system. The voltage regulator  7026  regulates the battery  7040  voltage. The handle processor  7024  receives inputs from the accelerometer  7020 . The VSS-ON/OFF Logic supply  7086  provides the input voltage to the handle processor  7024  and the VSS input to the DC-DC converter  7058 . 
     A tri-color LED  7072  is electrically coupled to the handle processor  7024 . The handle processor  7024  energizes either the red, blue, or green LED  7072  to provide visual feedback. 
     Three Hall effect sensor  7028  U 10 , U 11 , U 12  provide three separate Hall effect outputs U 1 _Hall 1 , U 1 _Hall 2 , U 1 _Hall 3  which are coupled to the handle processor  7024  as shown. The U 1 _Hall 3  output drives an onboard LED  7088 . In one aspect, the Hall effect sensor outputs U 1 _Hall 1 , U 1 _Hall 2 , U 1 _Hall 3 , and the ANALOG_CLAMP signal are coupled to the handle processor  7024  to determine the position of the clamp arm and the cutting member at the end effector portion of the modular motor driven surgical instrument  7000 , or the positions of other elements of the instrument  7000 . 
     The user switch  7070  is a representative example of the previously described “rocker-trigger”  110  that is pivotally mounted to a pistol grip portion of the handle. The user switch  7070  is operable to actuate a first motor switch  7044  that is operably coupled to the handle processor  7024 . The first motor switch  7044  may comprise a pressure switch which is actuated by pivoting the user switch  7070  into contact therewith. Actuation of the first motor switch  7044  will result in actuation of the motor  7038  such that the drive gear rotates in a first rotary direction. A second motor switch  7046  is also coupled to the handle processor  7024  and mounted for selective contact by the user switch  7070 . Actuation of the second motor switch  7046  will result in actuation of the motor  7038  such that the drive gear is rotated in a second direction. A fire switch  7048  is coupled to handle processor  7024 . Actuation of the fire switch  7048  results in the axial movement of the transmission carriage to advance the cutting element as was described above. 
     A Joint Test Action Group (JTAG)  7074  input is also coupled to the handle processor  7024 . The JTAG  7074  input is the IEEE 1149.1 Standard Test Access Port and Boundary-Scan Architecture devised for integrated circuit (IC) debug ports. The handle processor  7024  implements the JTAG  7074  to perform debugging operations like single stepping and breakpointing. 
     A UART  7076  is coupled to the handle processor  7024 . The UART  7076  translates data between parallel and serial forms. The UART  7076  is commonly used in conjunction with communication standards such as EIA, RS-232, RS-422 or RS-485. The universal designation indicates that the data format and transmission speeds are configurable. The electric signaling levels and methods (such as differential signaling etc.) are handled by a driver circuit external to the UART  7076 . The UART  7076  may be an individual (or part of an) integrated circuit used for serial communications over the serial port of the handle processor  1024 . The UART  7076  can be included in the handle processor  1024 . 
     A description of the remaining functional and operational aspects of the electrical subsystem  7006  of the handle portion  7002  of the modular motor driven surgical instrument  7000  will now be provided in connection with  FIG.  63 B . As shown, the handle processor  7024  provides a signal to drive the solenoid  7032 . A shaft module  7078  provides position signals SHAFT_IDO, SHAFT_ID 1 , CLAMP_HOME, and FIRE_HOME to the handle processor  7024 . A gear position module  7080  provides the position of the clamp and the cutting element to the handle processor  7024 . The positional information provided by the shaft module  7078  and the gear position module  7080  enable the handle processor  7024  to properly activate the motor  7038  when the user switch  7070  signals are received to open the clamp, close the clamp, and/or fire the cutting element. 
     The motor controller  7022  receives commands from the handle processor  7024  and provides commands to the MOSFET driver  7084 , which drives the 3-phase BLDC motor  7038  ( FIG.  61   ). As previously described, the BLDC motor controller  7022  must direct the rotation of the rotor. Accordingly, the BLDC motor controller/driver  7022  determines the position/orientation of the rotor relative to the stator coils. Accordingly, the rotor part of the BLDC motor  7038  is configured with Hall effect sensors  7028  to directly measure the position of the rotor. The BLDC motor controller  7022  contains 3 bi-directional outputs (i.e., frequency controlled three phase output), which are controlled by a logic circuit. 
     Accordingly, as described in  FIGS.  61 ,  63 A,  63 B, and  64    a motor control system comprising the motor controller  7022 , the motor driver  7084 , the motor Hall effect sensors  7028  in combination with the gear position module  7080  and/or the shaft module  7078  is operable to synchronize the gears such that the male couplers in the handle portion smoothly couple with the female couplers in the shaft portion of the surgical instruments described herein. In one instance, for example, although some tolerances may be provided for ease of shifting or keying, the motor control system is configured to track the position of the gears to ensure that the gears do not stop in a position that would prohibit shifting from one to the other or installing the two rotary keyings. In another instance, the motor may be configured to be slowly indexed during installation or shifting to resolve any minor out of synchronization conditions. These same issues may be encountered with the example described in connection with  FIG.  6    when the instrument shifts between two drives and not just when installing new end-effectors. This situation may be resolved by proper synchronization of the gears employing the motor control system described in connection with  FIGS.  61 ,  63 A,  63 B, and  64   . In other instances, encoders may be provided to track the rotations of the gears/gear shafts. 
       FIG.  64    is block diagram of the electrical system of the handle and shaft portions of the modular motor driven surgical instrument. As shown in  FIG.  64   , the handle processor  7024  receives inputs from the open switch  7044 , close switch  7046 , fire switch  7048 , clamp position switch  7034 , and fire position switch  7036 . In addition, the handle processor  7024  receives inputs from a clamp home switch  7090  and a fire home switch  7092  from the shaft module  7078 . Using various combinations of these switch inputs, the handle processor  7024  provides the proper commands to the motor  7038  and the solenoid  7032 . A battery monitoring circuit  7088  monitors the power input to the handle processor  7024  relative to ground. The handle processor  7024  drives the tri-color LED  7072 . The accelerometer  7020  provides three-axis orientation inputs to the handle processor  7024  to determine various parameters such as orientation of the instrument  7000  and whether the instrument  7000  has been dropped. The voltage regulator  7026  provides the regulated power supply for the system. A current sensing module  7094  is provided to sense the current drawn from the power supply. 
       FIG.  65    illustrates a mechanical switching motion control system  7095  to eliminate microprocessor control of motor functions. In the system described in connection with  FIGS.  61 - 64   , a microprocessor such as the handle processor  7024  is employed to control the function of the motor  7038 . The handle processor  7024  executes a control algorithm based on the various states of the switches deployed throughout the instrument  7000 . This requires the use of the handle processor  7024  and associated identification functions to provide control for different end effectors. 
     As shown in  FIG.  65   , however, an alternative technique may be employed to control the motor  7038  that eliminates the need for the handle processor  7024  by placing motion related switched  7096 A,  7096 B,  7096 C,  7096 D in the end effector shaft. The switches  7096 A-D are then configured to turn on and off specific functions of the motor  7038  or to reverse the direction of the motor  7038  based on where specific end effector components are positioned. In one instance, a switch that indicates full deployment of the cutting member could be employed to switch the functions of the motor  7038  to reverse direction and withdraw the cutting member. In another instance, the switches  7096 A-D could be configured to detect pressure or force such that a simple closure of the anvil down on the tissue would provide an on/off signal back to the closure motor  7038  to stop the closure motion. 
     In various instances, a surgical instrument can include a handle, an electric motor positioned within the handle, a shaft attachable to the handle, and an end effector extending from the shaft, wherein the electric motor is configured to motivate an end effector function at the end effector. In some instances, the surgical instrument can include a control system comprising one or more sensors and a microprocessor which can receive input signals from the sensors, monitor the operation of the surgical instrument, and operate the electric motor to perform the end effector function in view of the sensor input signals. In at least one such instance, the handle of the surgical instrument can be usable with more than one shaft. For instance, a linear stapling shaft or a circular stapling shaft could be assembled to the handle. The handle can include at least one sensor configured to detect the type of shaft that has been assembled thereto and communicate this information to the microprocessor. The microprocessor may operate the electric motor differently in response to the sensor input signals depending on the type of the shaft that has been assembled to the handle. For instance, if the electric motor is configured to operate a closing system of the end effector, the microprocessor will rotate the electric motor in a first direction to close an anvil of the circular stapler shaft and a second, or opposite, direction to close an anvil of the linear stapler shaft. Other control systems are envisioned in which the same operational control of the electric motor can be achieved without the use of a microprocessor. In at least one such instance, the shafts and/or the handle of the surgical instrument can include switches which can operate the surgical instrument differently depending on the type of the shaft that has been assembled to the handle. 
     In various instances, a surgical instrument system can include a power source, a first motor configured to perform a first end effector function, a second motor configured to perform a second end effector function, and a control system of switches configured to selectively place the power source in communication with the first motor and the second motor in response to the control system of switches. In various instances, such a surgical instrument system may not include a microprocessor. The first motor can comprise a closing motor of a closing system configured to close an anvil of the end effector and the second motor can comprise a firing motor of a firing system configured to fire staples from a staple cartridge of the end effector. The control system of switches can include a closure trigger switch which, when closed, can close a closure power circuit which couples the power source to the closing motor. The control system can further include a closure end-of-stroke switch which can be opened by the closure system when the anvil is in a fully closed position and open the closure power circuit to stop the closing motor and the closure drive. The control system of switches can also include a firing trigger switch which can be part of a firing power circuit which couples the power source to the firing motor. In various circumstances, the default condition of the firing power circuit can be open which can prevent the firing motor from being operated prior to firing power circuit being closed. Thus, closing the firing switch alone may not close the firing power circuit and operate the firing motor. The firing power circuit can further include a second closure end-of-stroke switch which can be closed by the closure system when the anvil is in a fully closed position. Closing the firing switch and the second closure end-of-stroke switch may close the firing power circuit and operate the firing motor. The control system can further include a firing end-of-stroke switch can be opened by the firing drive when the firing drive reaches the end of its firing stroke. The opening of the firing end-of-stroke switch can open the firing power circuit and stop the firing motor. The control system can further include a second firing end-of-stroke switch which can be closed by the firing drive to close a reverse firing power circuit which reverses the polarity of the power applied to the firing motor and operates the firing motor in an opposite direction and retracts the firing drive. Closing the reverse firing power circuit may also require the firing trigger switch to be in a closed condition. When the firing drive reaches its fully-retracted position, it can close a proximal firing switch. The closure of the proximal firing switch can close a reverse closing power circuit which can reverse the polarity of the power applied to the closing motor and operate the closing motor in an opposite direction and open the anvil. Closing the reverse closure power circuit may also require the closure trigger switch to be in a closed condition. When the anvil reaches its fully-open position, the anvil can open a proximal closure switch which can open the reverse closing power circuit and stop the closing motor. This is but one example. 
     In various instances, as described herein, a handle of a surgical instrument can be used with several different shaft assemblies which can be selectively attached to the handle. In some instances, as also described herein, the handle can be configured to detect the type of shaft that has been assembled to the handle and operate the handle in accordance with a control system contained within the handle. For instance, a handle can include a microprocessor and at least one memory unit which can store and execute a plurality of operating programs, each of which are configured to operate a specific shaft assembly. Other embodiments are envisioned in which the handle does not include a control system; rather, the shaft assemblies can each comprise their own control system. For instance, a first shaft assembly can comprise a first control system and a second shaft assembly can comprise a second control system, and so forth. In various instances, the handle may comprise an electrical motor, a power source, such as a battery and/or an input cable, for example, and an electrical circuit configured to operate the electrical motor based on control inputs from the attached shaft assembly. The handle may further comprise an actuator which, in conjunction with the shaft control system, may control the electrical motor. In various instances, the handle may not comprise additional control logic and/or a microprocessor, for example, for controlling the electrical motor. With the exception of the handle actuator, the control system of the shaft assembly attached to the handle would include the control logic needed to operate the electrical motor. In various instances, the control system of the shaft assembly may include a microprocessor while, in other instances, it may not. In some instances, the first control system of a first shaft assembly can include a first microprocessor and the second control system of a second shaft assembly can include a second microprocessor, and so forth. In various instances, a handle can include a first electrical motor, such as a closing motor, for example, and a second electrical motor, such as a firing motor, for example, wherein the control system of the attached shaft assembly can operate the closing motor and the firing motor. In certain instances, the handle can comprise a closing actuator and a firing actuator. With the exception of the closing actuator and the firing actuator, the control system of the shaft assembly attached to the handle would include the control logic needed to operate the closing motor and the firing motor. In various instances, a handle can include a shaft interface and each shaft assembly can include a handle interface configured to engage the shaft interface. The shaft interface can include an electrical connector configured to engage an electrical connector of the handle interface when a shaft assembly is assembled to the handle. In at least one instance, each connector may comprise only one electrical contact which are mated together such that only one control path is present between the handle and the shaft assembly. In other instances, each connector may comprise only two electrical contacts which form two mated pairs when the shaft assembly is attached to the handle. In such instances, only two control paths may be present between the handle and the shaft assembly. Other embodiments are envisioned in which more than two control paths are present between the handle and the shaft assembly. 
     In various instances, surgical end effector attachments can be compatible with a surgical instrument handle. For example, a surgical end effector can be coupled to the handle of a surgical instrument and can deliver and/or implement a drive motion that was initiated in the handle of the surgical instrument. Referring to  FIGS.  73  and  74   , the surgical end effector  8010  can be one of the several surgical end effectors that can be compatible with the handle  8000  of a surgical instrument. Various different surgical end effectors are described throughout the present disclosure and are depicted throughout the associated figures. The reader will appreciate that these various, different surgical end effectors described and depicted herein may be compatible with the same surgical instrument handle and/or can be compatible with more than one type of surgical instrument handle, for example. 
     The handle  8000  can include drive systems, for example, which can be configured to transfer a drive motion from the handle  8000  of the surgical instrument to a component, assembly and/or system of the end effector  8010 . For example, the handle  8000  can include a first drive system  8002   a  and a second drive system  8004   a . In certain instances, one of the drive systems  8002   a ,  8004   a  can be configured to deliver a closing drive motion to the jaw assembly of the end effector  8010  ( FIG.  73   ), for example, and one of the drive systems  8002   a ,  8004   a  can be configured to deliver a firing drive motion to a firing element in the end effector  8010 , for example. The drive systems  8002   a ,  8004   a  can be configured to transfer a linear motion, displacement, and/or translation from the handle  8000  to the end effector  8010 . In various instances, the first drive system  8002   a  can include a drive bar  8006 , which can be configured to translate and/or be linearly displaced upon activation of the first drive system  8002   a . Similarly, the second drive system  8004   a  can include a drive bar  8008 , which can be configured to translate and/or be linearly displaced upon activation of the second drive system  8004   a.    
     In various instances, the end effector assembly  8010  can include a first drive system  8002   b , which can correspond to the first drive system  8002   a  of the handle  8000 , for example, and can also include a second drive system  8004   b , which can correspond to the second drive system  8004   a  of the handle  8000 , for example. In various instances, the first drive system  8002   b  in the end effector  8010  can include a drive element  8012 , which can be operably and releasably coupled to the drive bar  8006  of the first drive system  8002   a  of the handle  8000 , for example, and can be configured to receive a linear motion from the drive bar  8006 , for example. Additionally, the second drive system  8004   b  of the end effector  8010  can include a drive element  8014 , which can be operably and releasably coupled to the drive bar  8008  of the second drive system  8004   a  of the handle  8000 , for example, and can be configured to receive a linear motion from the drive bar  8008 , for example. 
     In various instances, the handle  8000  and/or the end effector  8010  can include a coupling arrangement, which can be configured to releasably couple the drive bar  8006  to the drive element  8012 , for example, and/or the drive bar  8008  to the drive element  8014 , for example. In other words, the coupling arrangement can couple the first drive system  8002   a  of the handle  8000  to the first drive system  8002   b  of the end effector  8010  and the second drive system  8004   a  of the handle  8000  to the second drive system  8004   b  of the end effector  8010  such that a drive force initiated in the handle  8000  of the surgical instrument can be transferred to the appropriate drive system  8002   b ,  8004   b  of the attached surgical end effector  8010 . Though the surgical system depicted in  FIGS.  73  and  74    includes a pair of drive systems  8002   a ,  8004   a  in the handle  8000  and a corresponding pair of drive system  8002   b ,  8004   b  in the end effector  8010 , the reader will appreciate that the various coupling arrangements disclosed herein can also be used in a surgical end effector and/or handle comprising a single drive system or more than two drive systems, for example. 
     In various instances, a coupling arrangement for coupling a drive system in the handle of a surgical instrument to a drive system in an attached end effector can include a latch, which can be configured to retain and secure the connection between the corresponding handle and end effector drive systems. As described in greater detail herein, the latch can be spring-loaded, and can be coupled to a trigger, for example, which can be configured to operably overcome the bias of a spring to unlock, open, and/or release the coupling arrangement, for example. In various instances, the coupling arrangement can include independent and/or discrete coupling mechanisms and/or joints for each drive system  8002   b ,  8004   b  in the surgical end effector  8010 . In such instances, one of the drive systems  8002   b ,  8004   b  can be activated without activating the other drive system  8002   b ,  8004   b . In other instances, the drive systems  8002   b ,  8004   b  can be activated simultaneously and/or concurrently, for example. 
     Referring now to  FIGS.  66 - 72   , a coupling arrangement  8100  for use with a surgical end effector is depicted. For example, a surgical end effector can be attached to a handle  8170  ( FIGS.  67 - 69   ) of a surgical instrument via the coupling arrangement  8100 , for example. In various instances, the coupling arrangement  8100  can include a coupler housing or frame  8102 , for example. The coupler housing  8102  can be positioned within a proximal attachment portion of the end effector, for example. Additionally, the coupler housing  8102  can include a carriage  8104 , for example, which can be configured to move relative to the coupler housing  8102 , for example. For example, the coupler housing  8102  can include a channel  8103 , which can be dimensioned and structured to receive the slidable and/or shiftable carriage  8104 . For example, the carriage  8104  can be restrained by the coupler housing  8102 , such that the carriage  8104  is movably held in the channel  8103  and is configured to move and/or slide within the channel  8103 . The channel  8103  can guide and/or restrain movement of the carriage  8014  relative to the housing  8102 , for example. In certain instances, the carriage  8104  can have a ramped surface, such as a ramp or wedge  8106 , for example, which can further guide and/or facilitate movement of the carriage  8104 , for example. 
     In various instances, the coupling arrangement  8100  can include a trigger  8120  in sliding engagement with the ramp  8106  of the carriage  8104 . For example, the trigger  8120  can include an inclined surface  8122  that is configured to slide along the ramp  8106  of the carriage  8104  when the trigger  8120  is moved between a first, or unactuated, position ( FIG.  68   ) and a second, or actuated, position ( FIGS.  67  and  69   ), for example. In certain instances, the coupling arrangement  8100  can include a guide, such as guide rails  8110 , for example, which can be positioned and structured to guide the trigger  8120  between the first, unactuated position and the second, actuated position, for example. For example, the coupler housing  8102  can include a pair of guide rails  8110 , which can define an actuation path for the trigger  8120 . 
     In various instances, when the trigger  8120  is moved along the actuation path defined by at least one guide rail  8110  in a direction D 1  ( FIGS.  67  and  69   ) from the unactuated position ( FIG.  68   ) to the actuated position ( FIGS.  67  and  69   ), for example, the carriage  8104  can be shifted downward or in a direction D 3  ( FIGS.  67  and  69   ) within the channel  8103  via the inclined surface  8122  of the trigger  8120  and the ramp  8106  of the carriage  8104 . Accordingly, activation of the trigger  8120  can shift the carriage  8104  relative to the coupler housing  8102 , trigger  8120  and/or various other components, assemblies, and/or systems of the coupling arrangement  8100 , for example. 
     In various instances, when the trigger  8120  is moved along at least one guide rail  8110  in a direction D 2  ( FIG.  68   ) from the actuated position ( FIGS.  67  and  69   ) to the unactuated position ( FIG.  68   ), for example, the carriage  8104  can be shifted upward or in a direction D 4  ( FIG.  68   ) within the channel  8103  via the inclined surface  8122  of the trigger  8120  and the ramp  8106  of the carriage  8104 . Accordingly, actuation of the trigger  8120  can affect movement of the carriage  8104  relative to the coupler housing  8102 , for example. In certain instances, a spring and/or other biasing mechanism can be configured to bias the carriage  8104  and/or the trigger  8120  toward a predefined position relative to the channel  8103  and/or the coupler housing  8102 , for example. 
     Referring now to  FIG.  66   , in various instances, a slot  8112  can be defined in the coupler housing  8102  and/or the end effector. The slot  8112  can be dimensioned to receive a drive member  8172  of the handle  8170  of a surgical instrument, for example. In certain instances, a pair of slots  8112  can be defined in the coupler housing  8102 , and each slot  8112  can be configured to receive one of the drive members  8172  of the handle  8170 , for example. As described in greater detail herein, the drive members  8172  can be coupled to and/or otherwise driven by a drive system in the handle  8170 . For example, each drive member  8172  can be coupled to and/or otherwise driven by a linear actuator of a drive system in the handle  8170 , which can be configured to translate and deliver a linear drive motion to the corresponding drive system in the end effector, for example. 
     In various instances, the carriage  8104  can also be configured to move and/or shift relative to a drive member socket  8130  of the coupling arrangement  8100 . The drive member socket  8130  can be configured to receive one of the drive members  8172  from the handle  8170 , for example. Referring primarily to  FIG.  71   , the socket  8103  can include an opening  8136 , which can be dimensioned and/or structured to receive a drive system component of the handle  8170 . For example, referring primarily to  FIG.  67   , the opening  8136  can be configured to receive a distal portion of the drive bar  8172 . In such instances, when the drive bar  8172  is secured within the opening  8136  in the socket  8130 , as described in greater detail herein, the socket  8130  can be configured to transfer a drive force from the handle  8170  to the surgical end effector via the drive bar  8172  and socket  8130  engagement, for example. 
     Referring still to  FIG.  67   , the drive bar  8172  can include a bevel  8176  and a groove or divot  8174 , for example, which can facilitate engagement and/or locking of the drive bar  8172  to the socket  8130 . In various instances, the drive member socket  8130  can be secured and/or fixed within the end effector and/or within the coupler housing  8102 , for example, and the carriage  8104  can be configured to move and/or shift relative to and/or around the socket  8130  when the carriage  8104  slides within the channel  8103  in the coupler housing  8102 . 
     Referring primarily to  FIG.  71   , the socket  8130  can include at least one flexible tab  8132   a ,  8132   b . The flexible tab  8132   a ,  8132   b  can be inwardly biased toward the opening  8136  and/or can include an inwardly-biased tooth, for example. In certain instances, the flexible tab  8132   a ,  8132   b  can include the tooth  8133 , for example, which can be configured to engage the groove  8174  in the drive bar  8172  when the drive bar  8172  is inserted into the opening  8136  in the socket  8130 . For example, the bevel  8176  of the drive bar  8172  can pass by the tooth  8133  within the socket opening  8136 , and can flex or deflect the tab  8132  outward from the opening  8136 . As the drive bar  8172  continues to enter the opening  8136  of the socket  8130 , the tooth  8136  of the tab  8132   a ,  8132   b  can engage or catch the groove  8174  in the drive bar  8172 . In such instances, the tooth  8136 -groove  8174  engagement can releasably hold the drive bar  8172  within the socket  8130 , for example. 
     In various instances, the socket  8130  can include a recess  8134 , which can be configured to receive a spring  8150 , for example. In other instances, the socket  8136  can include more than one recess  8134 , and the coupling arrangement  8100  can include more than one spring  8150 , for example. Moreover, in certain instances, the socket  8130  can include more than one flexible tab  8132   a ,  8132   b . For example, the socket  8130  can include a pair of laterally-positioned tabs  8132   a ,  8132   b . A first tab  8132   a  can be positioned on a first lateral side of the socket  8130 , for example, and a second tab  8132   b  can be positioned on a second lateral side of the socket  8130 , for example. In certain instances, the tabs  8132   a ,  8132   b  can be deflected outward from the opening  8136  to accommodate entry of the drive bar  8172 , for example. In other instances, the socket  8130  may not include an inwardly-biased tab and/or can include more than two tabs, for example. 
     In various instances, the coupling arrangement  8100  can also include a latch or sleeve  8140 , which can be movably positioned relative to the socket  8130 . For example, the latch  8140  can include an opening  8142  ( FIG.  72   ), which can be dimensioned and structured to at least partially surround at least a portion of the socket  8130 . For example, the latch  8140  can be positioned around the socket  8130 , and can be movably positioned relative to the tabs  8132   a ,  8132   b  of the socket  8130 , for example. In various instances, the spring  8150  can be positioned between a portion of the socket  8130  and a portion of the latch  8140 , for example, such that the spring  8150  can bias the latch  8140  toward a socket-latching position ( FIG.  68   ). For example, the spring  8150  can bias the latch  8140  into the socket-latching position ( FIG.  68   ) in which the latch  8140  is positioned to surround and/or restrain outward deflection of the tab(s)  8132   a ,  8132   b.    
     In various instances, when the latch  8140  is positioned to limit and/or prevent outward deflection of the tab(s)  8132   a ,  8132   b , i.e., in the socket-latching position, outward movement of the tab(s)  8132   a ,  8132   b  away from the opening  8136  can be limited, such that the tab(s)  8132   a ,  8132   b  can block and/or otherwise prevent entry and/or release of the drive bar  8172  relative to the opening  8136  in the socket  8130 , for example. Moreover, when the trigger  8120  moves from the unactuated position ( FIG.  68   ) to the actuated position ( FIGS.  67  and  69   ), the latch  8140  can overcome the bias of the spring(s)  8150 , for example, and can be moved from the socket-latching position ( FIG.  68   ) to an unlatched position ( FIGS.  67  and  69   ). When in the unlatched position, the latch  8140  can be shifted away from the flexible tab(s)  8132   a ,  8132   b , such that the flexible tab(s)  8132   a ,  8132   b  can be deflected outward, for example, and the socket  8130  can receive the drive bar  8172 , for example. 
     In various instances, the latch  8140  can comprise a nub or protrusion  8144 . Furthermore, referring primarily to  FIG.  70   , the carriage  8104  in the coupler housing  8102  can include a biasing member  8108 . The biasing member  8108  can include a ramp or angled surface, for example, which can be configured to bias the nub  8144 , and thus the latch  8140 , between the first or socket-latching position ( FIGS.  67  and  69   ) and the second, or latched, position ( FIG.  68   ), for example. For example, when movement of the trigger  8120  causes the carriage  8104  to shift relative to the coupler housing  8102  and the socket  8130 , as described herein, the nub  8144  can slide along the angled surface of the biasing member  8108 , such that the latch  8140  moves relative to the flexible tab  8132  of the socket  8130 . In such instances, the activation of the trigger  8120  can overcome the bias of the spring  8150  and retract the latch  8140  from the socket-latching position around the flexible tab(s)  8132  of the socket  8130  to the unlatched position. In such instances, when the latch  8140  is retracted, the flexible tab(s)  8132  can be permitted to deflect and/or engage a driving bar  8172 . Moreover, when the trigger is unactuated, the spring  8150  can bias the latch  8140  relative to and/or around the flexible tab(s)  8132   a ,  8132   b , such that deflection of the tab(s)  8132   a ,  8132   b , and thus engagement with a drive bar  8172 , is limited and/or prevented, for example. 
     In certain instances, the latch  8140  can include a pair of laterally-opposed nubs  8144 , which can slidably engage laterally-opposed biasing members  8108  of the carriage  8104 . Furthermore, in instances where the coupling arrangement  8100  couples more than one drive system between the handle  8170  and the surgical end effector, for example, the carriage  8104  can include multiple biasing members  8108 , and/or multiple pairs of biasing members  8108 . For example, each socket  8130  can include a pair of laterally positioned nubs  8144 , and the carriage  8104  can include a biasing member  8108  for each nub  8144 , for example. 
     Referring primarily to  FIG.  68   , prior to activation of the trigger  8120  and/or upon release of the trigger  8120 , the trigger  8120  can be positioned in the distal, unactuated position, the carriage  8104  can be positioned in the lifted position relative to the coupler housing  8102 , and the latch  8140  can be positioned in the socket-latching position. In such an arrangement, the latch  8140  can prevent entry and/or engagement of the drive bar  8172  with the socket  8130 , for example. In various instances, spring(s)  8150  and/or a different spring and/or biasing member can bias the trigger  8120  into the unactuated position, the carriage  8104  into the lifted position, and/or the latch  8140  into the socket-latching position, for example. To connect and/or attach one of the drive bars  8172  to one of the sockets  8130 , referring now to  FIG.  67   , the trigger  8120  can be moved to the proximal, actuated position, which can shift the carriage  8104  to the lowered position, which can shift the latch  8140  to the unlatched position, for example. In such an arrangement, a drive bar  8172  can be configured to enter and/or be received by the socket  8130 , for example. 
     Thereafter, if the trigger  8120  is released, referring now to  FIG.  68   , for example, the spring(s)  8150  can bias the trigger  8120  back to the distal, unactuated position, can bias the carriage  8104  back to the lifted position, and can bias the latch  8140  back to a socket-latching position. Accordingly, the drive member  8172  can be locked into engagement with the socket  8130  because the latch  8140  can prevent outward deflection of the flexible tabs  8132   a ,  8132   b , and thus, can secure the drive member  8172  within the socket  8130 , for example. Accordingly, referring now to  FIG.  69   , to decouple the drive member  8172  from the socket  8130 , the trigger  8120  can again be moved to the proximal, actuated position, which can shift the carriage  8104  to the lowered position, which can shift the latch  8140  to the unlatched position, for example. In such an arrangement, i.e., when the socket  8130  is unlatched, the drive member  8172  can be removed from the socket  8130 , for example. 
     In various instances, a surgical instrument can include a drive system coupled to a motor. In certain instances, the motor and the drive system can affect various surgical functions. For example, the motor and the drive system can affect opening and/or closing of a surgical end effector, and can affect a cutting and/or firing stroke, for example. In certain instances, the motor and drive system can affect multiple distinct surgical functions. For example, opening and closing of the surgical end effector can be separate and distinct from cutting and/or firing of fasteners from the surgical end effector. In such instances, the drive system can include a transmission and/or clutch assembly, which can shift engagement of the drive system between different output systems, for example. 
     In various instances, a surgical instrument can include a drive system having multiple output shafts, and a clutch for shifting between the different output shafts. In certain instances, the output shafts can correspond to different surgical functions. For example, a first output shaft can correspond to an end effector closure motion, and a second output shaft can correspond to an end effector firing motion, for example. In various instances, the drive system can switch between engagement with the first output shaft and the second output shaft, for example, such that the surgical functions are separate and distinct and/or independent. For example, an end effector closure motion can be separate and distinct from an end effector firing motion. For example, it may be preferable to initiate a closure motion and, upon completion of the closure motion, initiate a separate firing motion. Moreover, it may be preferable to control and/or drive the independent closure motion and firing motion with a single drive system, which can be coupled to an electric motor, for example. In other instances, the first output shaft and the second output shaft can be operably coupled and the various surgical functions and/or surgical motions can occur simultaneously and/or at least partially simultaneously, for example. 
     Referring now to  FIGS.  75 - 78   , a handle  8600  for a surgical instrument can include a drive system  8602 , which can include a first output drive system  8610  and a second output drive system  8620 , for example. In various instances, when an end effector is attached to the handle  8600 , the first output drive system  8610  can be coupled to a first drive system in the attached end effector, and the second output drive system  8620  can be coupled to a second drive system in the attached end effector. The first output drive system  8610  can affect a first surgical function, such as clamping of the end effector jaws, for example, and the second output drive system  8620  can affect a second surgical function, such as firing of a firing element through the end effector, for example. In other instances, the surgical functions with respect to the first output drive system  8610  and the second output drive system  8620  can be reversed and/or otherwise modified, for example. 
     In various instances, the drive system  8602  can include a motor assembly, which can include an electric motor  8640  and a motor shaft  8642 . A drive gear  8644  can be mounted to the motor shaft  8642 , for example, such that the electric motor  8640  drives and/or affects rotation of the drive gear  8644 . In various instances, the first output drive system  8610  can include a first drive shaft  8612  and a first driven gear  8612 . The first driven gear  8614  can be mounted to the first drive shaft  8612 , for example, such that the rotation of the first driven gear  8614  affects the rotation of the first drive shaft  8612 . In various instances, a linear actuator  8616  can be threadably positioned on the first drive shaft  8612 , and rotation of the first drive shaft  8612  can affect linear displacement of the linear actuator  8616 , for example. Moreover, in various instances, the second output drive system  8620  can include a second drive shaft  8622  and a second driven gear  8624 . The second driven gear  8624  can be mounted to the second drive shaft  8622 , for example, such that the rotation of the second driven gear  8624  affects the rotation of the second drive shaft  8622 . In various instances, a linear actuator  8626  can be threadably positioned on the second drive shaft  8624 , and rotation of the second drive shaft  8624  can affect linear displacement of the linear actuator  8626 , for example. 
     In various instances, the drive system  8602  can further comprise a transmission or shifter assembly  8648 . The shifter assembly  8648  can be configured to shift engagement of the drive gear  8644  between the first output drive system  8610  and the second output drive system  8620 , for example. For certain instances, the shifter assembly  8648  can include a shifting gear  8652 , which can be in meshing engagement with the drive gear  8644 , for example. Additionally, the shifting gear  8652  can be configured to shift or move between a range of positions, for example, and can remain in meshing engagement with the drive gear  8644  as the shifting gear  8652  moves within the range of positions. 
     For example, the shifting gear  8652  can move into and/or out of engagement with at least one of the first driven gear  8614  and/or the second driven gear  8624 . In various instances, the shifting gear  8652  can move into meshing engagement with the second driven gear  8624  of the second output drive system  8620 . For example, when in a first position ( FIG.  78   ) of the range of positions, the shifting gear  8652  can be disengaged from the second driven gear  8624 , and when in a second position ( FIG.  77   ) of the range of positions, the shifting gear  8652  can be engaged with the second driven gear  8624 , for example. In instances when the shifting gear  8652  is engaged with the second driven gear  8624 , the shifting gear  8652  can transfer a force from drive gear  8644  to the second driven gear  8624 , such that the motor  8640  can affect a surgical function via the second output drive system  8620 , for example. Moreover, in instances when the shifting gear  8652  is disengaged from the second driven gear  8624 , rotation of the motor  8640  may not be transferred to the second output drive system  8620 , for example. 
     In various instances, the shifter assembly  8648  can further comprise an intermediate and/or transfer gear  8654 . The transfer gear  8642  can be configured to transfer a drive force from the shifting gear  8652  to the first driven gear  8614 , for example. In various instances, the transfer gear  8654  can be in meshing engagement with the first drive gear  8614 , for example, such that the rotation of the transfer gear  8654  is transferred to the first driven gear  8614 , for example. Moreover, in various instances the shifting gear  8652  can move into and/or out of engagement with the transfer gear  8654 . For example, when in the first position ( FIG.  78   ) of the range of positions, the shifting gear  8652  can be engaged with the transfer gear  8654 , and when in the second position ( FIG.  77   ) of the range of positions, the shifting gear  8652  can be disengaged from the transfer gear  8654 , for example. In instances when the shifting gear  8652  is engaged with the transfer gear  8654 , the shifting gear  8652  can transfer a force from the drive gear  8644  to the first driven gear  8614  via the transfer gear  8654 . In such instances, the motor  8640  can affect a surgical function via the first output drive system  8610 , for example. Moreover, in instances when the shifting gear  8652  is disengaged from the transfer gear  8654 , rotation of the motor  8640  may not be transferred to the first output drive system  8610 , for example. 
     In various instances, the transfer gear  8654  can be rotatably mounted on the second drive shaft  8622  of the second output drive system  8620 . For example, the transfer gear  8654  can be configured to rotate relative to the second drive shaft  8622  without affecting rotation of the second drive shaft  8622  and the second driven gear  8624  fixed thereto. In various instances, the shifter assembly  8648  can include a bracket or collar  8650 , which can at least partially surround the shifting gear  8652 . The bracket  8650  can be positioned around the shifting gear  8652 , for example, such that movement of the bracket  8650  can move the shifting gear  8652 . 
     In various instances, the handle  8600  and/or the shifting assembly  8648  can further include a trigger or clutch  8630 . The clutch  8630  can be configured to shift the bracket  8650  and/or the shifting gear  8652  within the range of positions. For example, clutch  8630  can comprise a trigger extending from the handle  8600 , and can be engaged with the bracket  8650  and/or the shifting gear  8652 . In various instances, the bracket  8650  can include a pin  8656 , which can extend from the bracket  8640  into an aperture  8638  ( FIG.  75   ) in the clutch  8630 . For example, the clutch  8630  can include an arm  8632  and/or a pair of arms  8632  coupled to a pivot point  8634  on the handle  8600 . The clutch  8630  can pivot at the pivot point  8634 , for example, and pivoting of the arm(s)  8632  can move the pin  8656  of the bracket  8560 . Movement of the bracket  8650  can shift the shifting gear  8652  between the first position ( FIG.  78   ) and the second position ( FIG.  77   ), for example. 
     In various instances, the movement of the bracket  8650  can be constrained such that the shifting gear  8652  moves along a longitudinal axis through its range of positions. Moreover, the pivoting stroke and/or range of movement of the clutch  8630  can be restrained and/or limited, for example, such that the shifting gear  8652  remains within the range of positions as the clutch  8630  pivots. Furthermore, the aperture  8638  ( FIG.  75   ) in the clutch  8630  can be configured and/or structured to maintain and/or hold the shifting gear  8652  within the range of positions and/or in alignment with one of the second driven gear  8624  and/or the transfer gear  8654 , for example. In various instances, the handle  8600  can include a spring or other biasing mechanism, to bias the shifting gear  8652  into one of the first position or the second position. In some instances, the handle  8600  can include a bistable complaint mechanism configured to hold the shifting gear  8652  in its first position or its second position. To the extent that the shifting gear  8652  is between the first position and the second position, the bistable compliant mechanism can be dynamically unstable and act to place the shifting gear  8652  in its first position or its second position. Alternatively, the shifting gear  8652  can be biased into an intermediate position, wherein the shifting gear  8652  can be simultaneously engaged with the first output drive system  8610  and the second output drive system  8620 , for example. Additionally or alternatively, the handle  8600  can include a lock and/or detent for holding the shifting gear  8652  in one of the first position or the second position, for example. 
     A surgical instrument can include a rotatable drive shaft configured to operate a closure drive and a firing drive of a surgical instrument. Referring to  FIGS.  79 - 84   , a surgical instrument  10000  can include a rotatable drive shaft  10020 , a closure drive  10030 , and a firing drive  10040 . As will be described in greater detail below, the drive shaft  10020  can include a first thread  10024  configured to operate the closure drive  10030  and a second thread  10026  configured to operate the firing drive  10040 . In various instances, the instrument  10000  can comprise a circular stapler, for example. 
     The surgical instrument  10000  can comprise a frame  10002  and means for generating a rotary motion. In certain instances, rotary motion can be created by a manually-driven hand crank, for example, while, in various instances, rotary motion can be created by an electric motor. In either event, the generated rotary motion can be transmitted to a rotary input shaft  10010 . Input shaft  10010  can include a proximal bearing portion  10011  and a distal bearing portion  10013  which are rotatably supported by the frame  10002 . In various instances, the proximal bearing portion  10011  and/or the distal bearing portion  10013  can be directly supported by the frame  10002  while, in certain instances, the proximal bearing portion  10011  and/or the distal bearing portion  10013  can include a bearing positioned between the input shaft  10010  and the frame  10002 . The input shaft  10010  can further include a gear  10012  mounted to and/or keyed to the input shaft  10010  such that, when input shaft  10010  is rotated in direction A ( FIG.  79   ), gear  10012  is also rotated in direction A. Correspondingly, when input shaft  10010  is rotated in an opposite direction, i.e., direction A′ ( FIG.  82   ), the gear  10012  is also rotated in direction A′. 
     Referring primarily to  FIGS.  79  and  80   , the drive shaft  10020  can include a proximal end  10021  and a distal end  10023 . The proximal end  10021  and the distal end  10023  can be rotatably supported by the frame  10002 . In various instances, the proximal end  10021  and/or the distal end  10023  can be directly supported by the frame  10002  while, in certain instances, the proximal end  10021  and/or the distal end  10023  can include a bearing positioned between the drive shaft  10020  and the frame  10002 . A gear  10022  can be mounted to and/or keyed to the proximal end  10021  of the drive shaft  10020 . The gear  10022  is meshingly engaged with the gear  10012  such that, when the input shaft  10010  is rotated in direction A, the drive shaft  10020  is rotated in direction B. Correspondingly, referring to  FIG.  81   , when the input shaft  10010  is rotated in direction A′, the drive shaft  10020  is rotated in direction B′. 
     Referring again to  FIG.  79   , the closure drive system  10030  can include a closure pin  10032  engaged with the first thread  10024  of the drive shaft  10020 . The closure drive system  10030  can further comprise a translatable closure member  10033 . The closure pin  10032  is positioned within an aperture defined in the proximal end of the closure member  10033 . The closure pin  10032  can include a first end positioned within the groove defined by the first thread  10024 . When the drive shaft  10020  is rotated, a sidewall of the groove can contact the first end of the closure pin  10032  and displace the closure pin  10032  proximally or distally, depending on the direction in which the drive shaft  10020  is being rotated. For example, when the drive shaft  10020  is rotated in direction B ( FIG.  79   ), the closure pin  10032  can be displaced, or translated, distally as indicated by direction D. Correspondingly, when the drive shaft  10020  is rotated in direction B′ ( FIG.  82   ), the closure pin  10032  can be displaced, or translated, proximally as indicated by direction P. The closure pin  10032  can be closely received within the aperture defined in the closure member  10033  such that the displacement, or translation, of the closure pin  10032  is transferred to the closure member  10033 . As the reader will appreciate, the closure pin  10032  and the closure member  10033  are constrained from rotating relative to the frame  10002  such that the rotation of the drive shaft  10020  is converted to the translation of the closure pin  10032  and the closure member  10033 . 
     Referring primarily to  FIG.  80   , the first thread  10024  extends along a first length  10025  of the drive shaft  10020 . In certain instances, the first thread  10024  may extend along the entire length of the drive shaft  10020  while, in other circumstances, the first thread  10024  may extend along less than the entire length of the drive shaft  10020 . The first thread  10024  can include a proximal portion adjacent the proximal end  10021  of the drive shaft  10020  and a distal portion adjacent the distal end  10023  of the drive shaft  10020 . When the closure pin  10032  is in the distal portion of the first thread  10024 , as illustrated in  FIG.  81   , the closure member  10033  can position an anvil of the surgical instrument  10000  in an open position. As the drive shaft  10020  is rotated in direction B′, the closure pin  10032  can translate proximally until the closure pin  10032  reaches the proximal portion of the first thread  10024 , as illustrated in  FIG.  82   . As the closure pin  10032  moves proximally, the closure pin  10032  can pull the closure member  10033  and the anvil proximally. When the closure pin  10032  reaches the proximal portion of the first thread  10024 , the anvil can be in a fully closed position. 
     Further to the above, the closure drive  10030  can be operated to move the anvil of the surgical instrument  10000  into a suitable position relative to a staple cartridge. In various instances, the surgical instrument  10000  can include an actuator which can be operated in a first direction to rotate the input shaft  10010  in direction A and the drive shaft  10020  in direction B and a second direction to rotate the input shaft  10010  in direction A′ and the drive shaft  10020  in direction B′. In other instances, the surgical instrument  10000  can include a first actuator configured to rotate the input shaft  10010  in direction A and the drive shaft  10020  in direction B, when operated, and a second actuator configured to rotate the input shaft  10010  in direction A′ and the drive shaft  10020  in direction B′, when operated. In either event, an operator of the surgical instrument  10000  can move the anvil of the surgical instrument  10000  toward and away from the staple cartridge, as needed, in order to create a desired gap between the anvil and the staple cartridge. Such a desired gap may or may not be created when the anvil is in its fully closed position. 
     Further to the above, the surgical instrument  10000  can include a catch configured to receive and releasably hold the drive pin  10032  when the closure system  10030  has reached its fully closed configuration. Referring primarily to  FIGS.  81  and  82   , the surgical instrument  10000  can include a catch bar  10073  comprising a catch aperture  10077  defined therein. As the drive pin  10032  is advanced proximally, the drive pin  10032  can become aligned with, and then at least partially enter, the catch aperture  10077 . The catch pin  10032  can be biased toward the catch bar  10073  by a spring  10035  positioned intermediate the closure member  10033  and a circumferential head  10037  extending around the catch pin  10032 . When the catch pin  10032  is positioned distally with respect to the catch aperture  10077 , the spring  10035  can bias the drive pin  10032  against the catch bar  10073 . When the catch pin  10032  is moved proximally by the rotation of the drive screw  10020  and becomes aligned with the catch aperture  10077 , the spring  10035  can move the drive pin  10032  upwardly into the catch aperture  10077 . The drive pin  10032  can be moved upwardly by the spring  10035  until the head of the drive pin  10032  contacts the catch bar  10073 . Notably, the movement of the drive pin  10032  toward the catch aperture  10077  can cause the drive pin  10032  to become operably disengaged from the first thread  10024 . Thus, the closure system  10030  can become deactivated when the drive pin  10032  reaches the catch aperture  10077  such that subsequent rotation of the drive shaft  10020  does not move the drive pin  10032 , the closure member  10033 , and the anvil operably engaged therewith, at least until the drive pin  10032  is re-engaged with the first thread  10024  as described in greater detail further below. 
     As discussed above, the entry of the drive pin  10032  into the catch aperture  10077  of the catch bar  10073  can demarcate the end of the closing stroke of the closure system  10030  and the fully closed position of the anvil. In various instances, the catch bar  10073  may not be movable relative to the frame  10002  and the catch aperture  10077  may demarcate a fixed position. In other instances, the catch bar  10073  may be movable relative to the frame  10002 . In such instances, the final, closed position of the anvil will depend on the position of the catch aperture  10077 . As a result, the gap between the anvil and the staple cartridge of the surgical instrument  10000  will depend on the position of the catch aperture  10077 . Referring generally to  FIG.  79   , the surgical instrument  10000  can further comprise a gap setting system  10070  configured to move the catch bar  10073 . The gap setting system  10070  can comprise a rotatable knob  10072  and a drive gear  10071  engaged with the rotatable knob  10072 . The catch bar  10073  can include a rack  10075  extending therefrom which comprises a plurality of teeth. The drive gear  10071  is meshingly engaged with the rack  10075  such that, when the knob  10072  is rotated in a first direction, the rack  10075  can drive the catch bar  10073  distally and, when the knob  10072  is rotated in a second direction opposite the first direction, the rack  10075  can drive the catch bar  10073  proximally. When the catch bar  10073  is moved distally, the catch aperture  10077  can be positioned such that a larger gap between the anvil and the staple cartridge may be present when the closure drive  10030  is in its fully closed position. When the catch bar  10073  is moved proximally, the catch aperture  10077  can be positioned such that a smaller gap between the anvil and the staple cartridge may be present when the closure drive  10030  is in its fully closed position. In various instances, the catch aperture  10077  can be positionable within a range of positions which can accommodate a range of distances between the anvil and the staple cartridge of the surgical instrument  10000 . 
     In various instances, the gap setting system  10070  can comprise a knob lock configured to releasably hold the knob  10072  in position. For instance, the frame  10002  can include a lock projection  10004  extending therefrom which can be received within one or more lock apertures  10074  defined in the knob  10072 . The lock apertures  10074  can be positioned along a circumferential path. Each lock aperture  10074  can correspond with a preset position of the closure drive  10030  and a preset gap distance between the anvil and the staple cartridge of the surgical instrument  10000 . For instance, when the lock projection  10004  is positioned in a first lock aperture  10074 , the closure drive  10030  can be held in a first preset position and, correspondingly, the anvil can be held a first preset distance from the staple cartridge. In order to move the knob  10072  into a second preset position, the knob  10072  can be lifted away from the frame  10002  such that lock projection  10004  is no longer positioned in the first lock aperture  10074 , rotated to drive the rack  10075  and the catch bar  10073 , and then moved toward the frame  10002  such that the lock projection  10004  enters into a second lock aperture  10074  defined in the knob  10072 . When the lock projection  10004  is positioned in the second lock aperture  10074 , the closure drive  10030  can be held in a second preset position and, correspondingly, the anvil can be held a second preset distance from the staple cartridge which is different than the first preset distance. In order to move the knob  10072  into a third preset position, the knob  10072  can be lifted away from the frame  10002  such that lock projection  10004  is no longer positioned in the first or second lock aperture  10074 , rotated to drive the rack  10075  and the catch bar  10073 , and then moved toward the frame  10002  such that the lock projection  10004  enters into a third lock aperture  10074  defined in the knob  10072 . When the lock projection  10004  is positioned in the third lock aperture  10074 , the closure drive  10030  can be held in a third preset position and, correspondingly, the anvil can be held a third preset distance from the staple cartridge which is different than the first and second preset distances. The gap setting system  10070  can further include a biasing element configured to bias the knob  10072  toward the frame  10002 . For instance, the gap setting system  10070  can include a spring  10076  positioned intermediate the housing  10002  and the drive gear  10071 , for example, configured to bias a lock aperture  10074  into engagement with the lock projection  10004 . 
     In certain instances, an operator of the surgical instrument  10000  may be able to discern the position of the closure system  10030  by observing the position of the anvil. In some instances, however, the anvil may not be visible in a surgical field. Referring primarily to  FIG.  79   , the surgical instrument  10000  can further comprise an anvil position indicator system  10050  configured to indicate the position of the anvil. The anvil position indicator system  10050  can include a window  10058  defined in the frame  10002  and a pivotable member  10051  observable through the window  10058 . The pivotable member  10051  can include a pivot  10052  rotatably mounted to the frame  10002 , a drive end  10054 , and a display end  10056 . The pivotable member  10051  can be movable between a first position ( FIG.  81   ) which indicates that the anvil is in a fully open position, a second position ( FIG.  82   ) which indicates that the anvil is in a fully closed position, and a range of positions between the first position and the second position which represent a range of positions of the anvil. The closure system  10030  can be configured to contact the drive end  10054  of the pivotable member  10051  to move the pivotable member  10051 . When the drive pin  10032  is moved proximally by the drive shaft  10020 , referring primarily to  FIG.  82   , the drive pin  10032  can pull the closure member  10033  proximally such that a shoulder  10036  defined on the closure member  10033  can contact the drive end  10054  of the pivotable member  10051  and rotate the pivotable member  10051  about the pivot  10052 . The rotation of the pivotable member  10051  can move the display end  10056  within the window  10058  to indicate the position of the anvil. To facilitate this observation, the frame  10002  and/or the window  10058  can include one or more demarcations  10059  which can indicate the position of the anvil. For instance, when the display end  10056  of the pivotable member  10051  is aligned with a proximal demarcation  10059  ( FIG.  81   ), the operator can determine that the anvil is in an open position and, when the display end  10056  is aligned with a distal demarcation  10059  ( FIG.  82   ), the operator can determine that the anvil is in a closed position. If the display end  10056  is positioned intermediate the proximal and distal demarcations  10059 , the operator can assume that the anvil is in a position between its open position and its closed position. Additional demarcations  10059  between the proximal and distal demarcations  10059  can be utilized to indicate additional positions of the anvil. When the closure member  10033  is moved distally to open the anvil ( FIG.  84   ), the pivotable member  10051  can rotate back into its first position and become aligned with the proximal demarcation  10059  once again. The position indicator system  10050  can further include a biasing member, such as a spring, for example, configured to bias the pivotable member  10051  into its first position. 
     As discussed above, the closure system  10030  of the surgical instrument  10000  can be operated to position the anvil of the surgical instrument  10000  relative to the staple cartridge. During the operation of the closure system  10030 , the firing system  10040  may not be operated. The firing system  10040  may not be operably engaged with the drive shaft  10020  until after the closure drive  10030  has reached its fully closed position. The surgical instrument  10000  can include a switch, such as switch  10060 , for example, configured to switch the surgical instrument between an anvil closure operating mode and a staple firing operating mode. The closure drive  10030  can further comprise a switch pin  10031  extending from the proximal end of the closure member  10033 . Upon comparing  FIGS.  81  and  82   , the reader will appreciate that the switch pin  10031  comes into contact with the switch  10060  as the closure pin  10032  is being advanced proximally to close the anvil. The switch  10060  can be pivotably mounted to the frame  10002  about a pivot  10062  and can include one or more arms  10064  extending therefrom. The switch pin  10031  can contact the arms  10064  and rotate the switch  10060  about the pivot  10062  when the drive pin  10032  reaches its fully closed position. The switch  10060  can further comprise an arm  10066  extending therefrom which can be configured to push a firing nut  10042  of the firing drive  10040  into operative engagement with the drive shaft  10020  when the switch  10060  is rotated about pivot  10062 . More particularly, in at least one circumstance, the arm  10066  can be configured to displace a push bar  10044  distally which can, in turn, push the firing nut  10042  onto the second thread  10026 . At such point, the drive pin  10032  and the closure system  10030  may be disengaged from the first thread  10024 , as a result of the catch aperture  10077  described above, and the firing nut  10042  and the firing system  10040  can be engaged with the second thread  10026 . 
     Further to the above, the firing nut  10042  can comprise a threaded aperture  10041  defined therein which can be threadably engaged with the second thread  10026 . When the closure drive  10030  is being operated, further to the above, the firing nut  10042  may be positioned proximally with respect to the second thread  10026  such that the threaded aperture  10041  is not threadably engaged with the second thread  10026 . In such circumstances, the firing nut  10042  may sit idle while the drive shaft  10020  is rotated to operate the closure system  10030 . When the firing nut  10042  is displaced distally, further to the above, the threaded aperture  10041  can become threadably engaged with the second thread  10026 . Once the firing nut  10042  is threadably engaged with the second thread  10026 , rotation of the drive shaft  10020  in direction B′ ( FIG.  82   ) will displace the firing nut  10042  distally. The firing nut  10042  can include one or more anti-rotation features, such as flanges  10043 , for example, which can be slidably engaged with the frame  10002  to prevent the firing nut  10042  from rotating with the drive shaft  10020 . The firing drive  10040  can further include a firing member coupled to the firing nut  10042  which can be pushed distally by the firing nut  10042 . The firing member can be configured to eject staples from the staple cartridge. When the firing nut  10042  reaches the distal end of the second thread  10026 , the firing nut  10042  may become threadably disengaged from the second thread  10026  wherein additional rotation of the drive shaft  10020  in direction B′ may no longer advance the firing nut  10042 . 
     Referring primarily to  FIGS.  82  and  83   , the surgical instrument  10000  can further comprise a reverse activator  10047  positioned at the distal end of the second thread  10026 . The firing nut  10042  can be configured to contact the reverse actuator  10047  and displace the reverse actuator  10047  distally when the firing nut  10042  reaches the distal end of the second thread  10026 . A biasing member, such as spring  10048 , for example, can be positioned intermediate the reverse actuator  10047  and the frame  10002  which can be configured to resist the distal movement of the reverse actuator  10047 . The distal movement of the reverse actuator  10047  can compress the spring  10048 , as illustrated in  FIG.  83   , and apply a proximal biasing force to the firing nut  10042 . When the drive shaft  10020  is rotated in direction B, the proximal biasing force applied to firing nut  10042  can re-engage the threaded aperture  10041  of the firing nut  10042  with the second thread  10026  and the firing nut  10042  can be moved proximally, as illustrated in  FIG.  84   . The proximal movement of the firing nut  10042  can move the firing member proximally. When moving proximally, the firing nut  10042  can displace the push bar  10044  such that the push bar  10044  contacts the arm  10066  of the switch  10060  and rotates the switch  10060  in an opposite direction back into its unswitched position. At such point, the firing nut  10042  may become threadably disengaged from the second thread  10026  and further rotation of drive shaft  10020  in direction B may no longer displace the firing nut  10042  proximally. At such point, the firing nut  10042  will have resumed its idle position. 
     When the switch  10060  is rotated back into its original position, further to the above, the arms  10064  of the switch  10060  can push the switch pin  10031  and the closure member  10033  distally. The distal movement of the switch pin  10031  and the closure member  10033  can displace the drive pin  10032  from the catch aperture  10077  defined in the catch bar  10073 . As the drive pin  10032  exits the catch aperture  10077 , the drive pin  10032  can move downwardly against the biasing force of the spring  10035  in order to slide under the catch bar  10073 . The downward movement of the drive pin  10032  can re-engage the drive pin  10032  with the first thread  10024 . Further rotation of the drive shaft  10020  in direction B will displace the drive pin  10032  and the closure member  10033  distally to open the anvil of the surgical instrument  10000 . At such point, the surgical instrument  10000  will have been reset for a subsequent use thereof. In various instances, the staple cartridge can be replaced and/or reloaded and the surgical instrument  10000  can be used once again. 
     As the reader will appreciate from the above, the drive screw  10020  can displace the drive pin  10032  to operate the closure drive  10030  and the firing nut  10042  to operate the firing drive  10040 . Further to the above, the drive screw  10020  can displace the drive pin  10032  along a first length  10025  of the drive screw  10020 . Similarly, the drive screw  10020  can displace the firing nut  10042  along a second length  10027  of the drive screw  10020 . The first length  10025  can define a closure stroke of the closure system  10030  and the second length  10027  can define a firing stroke of the firing stroke  10040 . The first length  10025  can be longer than the second length  10027 , although the second length  10027  could be longer than the first length  10025  in certain circumstances. In use, the closure pin  10032  can pass by the firing nut  10042 . For instance, when the closure pin  10032  is moved proximally to close the anvil, the closure pin  10032  can pass by the firing nut  10042  when the firing nut  10042  is in its idle position. Similarly, the closure pin  10032  can pass by the firing nut  10042  in its idle position when the closure pin  10032  is moved distally to open the anvil. In order to facilitate this relative movement, the firing nut  10042  can include an opening, such as slot  10046 , for example, defined therein through which the closure pin  10032  can pass as the closure pin  10032  moves relative to the firing nut  10042 . Such an opening defined in the firing nut  10042  could also permit the firing nut  10042  to slide by the closure pin  10032  in various other embodiments. 
     Further to the above, the first length  10025  and the second length  10027  can at least partially overlap. Moreover, the first thread  10024  and the second thread  10026  can at least partially overlap. The first thread  10024  and the second thread  10026  can be defined on the same portion of the drive screw  10020 . The first thread  10024  and the second thread  10026  can be sufficiently dissimilar such that the closure pin  10032  does not follow the second thread  10026  and such that the firing nut  10042  does not follow the first thread  10024 . For instance, the first thread  10024  can include a first thread pitch and the second thread  10026  can include a second thread pitch which is different than the first thread pitch. The first thread pitch of the first thread  10024  may or may not be constant. In the event that the first thread pitch is constant, the closure pin  10032  and the anvil operably engaged with the first thread  10024  will move at a constant speed throughout the closure stroke for a given rotational speed of the drive shaft  10020 . In the event that the first thread pitch is not constant, the closure pin  10032  and the anvil will move at different speeds during the closure stroke for a given rotational speed of the drive shaft  10020 . For instance, the distal portion of the first thread  10024  can include a thread pitch which is greater than the thread pitch of the proximal portion of the first thread  10024 . In such circumstances, the anvil will move quickly away from its open position and move slower once it nears its closed position for a given rotational speed of the drive shaft  10020 . Such an arrangement would permit the anvil to be moved quickly into position against tissue positioned intermediate the anvil and the staple cartridge and then slower once the anvil was engaged with the tissue in order to mitigate the possibility of over-compressing the tissue. In various other instances, the distal portion of the first thread  10024  can include a thread pitch which is less than the thread pitch of the proximal portion of the first thread  10024 . In either event, the thread pitch can change between the ends of the first thread  10024 . This change can be linear and/or non-linear. 
     Further to the above, the second thread pitch of the second thread  10026  may or may not be constant. In the event that the second thread pitch is constant, the firing nut  10042  and the firing member operably engaged with the second thread  10026  will move at a constant speed throughout the closure stroke for a given rotational speed of the drive shaft  10020 . In the event that the second thread pitch is not constant, the firing nut  10042  and the firing member will move at different speeds during the firing stroke for a given rotational speed of the drive shaft  10020 . For instance, the distal portion of the second thread  10026  can include a thread pitch which is less than the thread pitch of the proximal portion of the second thread  10026 . In such circumstances, the firing member will move slower at the end of its firing stroke for a given rotational speed of the drive shaft  10020 . Such an arrangement would slow the firing member down as it reached the end of the staple forming process. Moreover, such an arrangement could generate a larger amount of torque at the end of the firing stroke which correlates with the completion of the staple forming process. In various other instances, the distal portion of the second thread  10026  can include a thread pitch which is greater than the thread pitch of the proximal portion of the second thread  10026 . In either event, the thread pitch can change between the ends of the second thread  10026 . This change can be linear and/or non-linear. 
     Turning now to  FIGS.  86 - 93   , a surgical instrument  10500  can include a shaft  10504  and an end effector  10505 . The end effector  10505  can include a staple cartridge  10506  and a movable anvil  10508 . The surgical instrument  10500  can include a closure drive including a closure member operably engageable with the anvil  10504  and a firing drive including a firing member configured to deploy staples from the staple cartridge  10506 . The surgical instrument  10500  can include means for generating a rotary motion such as a hand crank and/or an electric motor, for example. The rotary motion can be transmitted to an input shaft  10510 . The surgical instrument  10500  can include a transmission  10502  which is configured to selectively transmit the rotation of the input shaft  10510  to the closure drive and to the firing drive, as discussed in greater detail further below. 
     The input shaft  10510  can include a input gear  10512  mounted and/or keyed thereto which rotates with the input shaft  10510 . The input shaft  10510  can be rotatably supported by a frame of the surgical instrument  10500  by a proximal end  10511  and a distal end  10519 . The input gear  10512  can be meshingly engaged with an intermediate gear  10522  mounted and/or keyed to an intermediate shaft  10520 . Thus, when input shaft  10510  and input gear  10512  are rotated in direction A ( FIG.  89   ), intermediate shaft  10520  and intermediate gear  10522  are rotated in direction B ( FIG.  89   ). Similar to the above, the intermediate shaft  10520  can be rotatably supported by the surgical instrument frame by a proximal end  10521  and a distal end  10529 . The intermediate shaft  10520  can further include a threaded portion  10524  which can be threadably engaged with a shifter block  10526 . Referring primarily to  FIG.  87   , the shifter block  10526  can include one or more threaded apertures  10527  threadably engaged with the threaded portion  10524 . When the intermediate shaft  10520  is rotated in direction B, referring primarily to  FIG.  89   , the intermediate shaft  10520  can displace the shifter block  10526  proximally. 
     Further to the above, the shifter block  10526  can include a gear slot  10528  defined therein. The input shaft  10510  can further include a slider gear  10516  slidably mounted thereto which is positioned in the gear slot  10528 . When the shifter block  10526  is moved proximally by the intermediate shaft  10520 , as discussed above, the shifter block  10526  can push the slider gear  10516  proximally along a keyed input shaft portion  10514 . Referring primarily to  FIG.  87   , the slider gear  10516  can include an aperture  10517  defined therein including one or more flat surfaces, for example, which are aligned with corresponding flat surfaces on the keyed input shaft portion  10514 . The flat surfaces of the aperture  10517  and the keyed input shaft portion  10514  can permit the slider gear  10516  to be slid longitudinally along the input shaft  10510  and, in addition, co-operate to transmit rotational motion between the slider gear  10516  and the input shaft  10510 . As will be described in greater detail below, the shifter block  10526  can slide the slider gear  10516  through a first range of positions in which the slider gear  10516  is engaged with a closure shaft  10530 , a second range of positions in which the slider gear  10516  is engaged with a firing shaft  10540 , and a null position, or a range of null positions, intermediate the first range and the second range of positions in which the slider gear  10516  is not engaged with either the closure shaft  10530  or the firing shaft  10540 . 
     Further to the above,  FIG.  85    depicts the anvil  10508  of the end effector  10505  in a fully closed position and a firing driver  10548  in an unfired position.  FIG.  86    depicts the transmission  10502  in a configuration which is consistent with the configuration of the end effector  10505  depicted in  FIG.  85   . More particularly, the slider gear  10516  is in its null, or idle, position and is not operably engaged with a closure shaft  10530  of the closure drive or a firing shaft  10540  of the firing drive. When the slider gear  10516  is in its idle position, the slider gear  10516  is positioned intermediate a closure gear  10532  mounted and/or keyed to the closure shaft  10530  and a firing gear  10542  mounted and/or keyed to the firing shaft  10540 . Moreover, the slider gear  10516  is not engaged with the closure gear  10532  or the firing gear  10542  when the slider gear  10516  is in its idle position. In order to move the anvil  10508  into its open position, and/or detach the anvil  10508  from the end effector  10505 , as illustrated in  FIG.  88   , the input shaft  10510  can be rotated in direction A, as illustrated in  FIG.  89   . As discussed above, the rotation of input shaft  10510  in direction A can rotate the intermediate shaft  10520  in direction B and move shifter block  10526  proximally. When the shifter block  10526  moves proximally, the shifter block  10526  can push the slider gear  10516  into operative engagement with the closure gear  10532 . At such point, the continued rotation of input shaft  10510  in direction A can be transmitted to the closure shaft  10530  via the meshingly engaged slider gear  10516  and closure gear  10532 . When the slider gear  10516  is meshingly engaged with the closure gear  10532 , the rotation of the input shaft  10510  in direction A will rotate the output shaft  10530  in direction C, as illustrated in  FIG.  89   . The closure drive can further include a closure nut  10536  comprising a threaded aperture  10537  defined therein which is threadably engaged with a threaded portion  10534  of the closure shaft  10530 . The closure nut  10536  can include one or more anti-rotation features slidably engaged with the frame of the surgical instrument, for example, which can prevent the closure nut  10536  from rotating with the closure shaft  10530  such that the rotational movement of the closure shaft  10530  can be converted to longitudinal movement of the closure nut  10536 . The closure system can further include a closure member  10538  extending from the closure nut  10536  which can be engaged with the anvil  10508 . When the closure shaft  10530  is rotated in direction C, referring again to  FIG.  89   , the closure nut  10536  and the closure member  10538  can be advanced distally to move the anvil  10508  into an open position. 
     Further to the above,  FIG.  89    depicts the transmission  10502  in a closure configuration, i.e., a configuration in which the anvil  10508  can be opened and closed. When the slider gear  10516  is meshingly engaged with the closure gear  10532 , the input shaft  10510  will directly drive the closure shaft  10530 . Concurrently, the input shaft  10510  will directly drive the intermediate shaft  10520  owing to the meshing engagement between the input gear  10512  and the intermediate gear  10522 . Also, when the slider gear  10516  is meshingly engaged with the closure gear  10532 , the slider gear  10516  is not meshingly engaged with the firing gear  10542  and, as such, the input shaft  10510  will not drive the firing shaft  10540  when the transmission  10502  is in the closure configuration. 
     Once the anvil  10508  has been moved into an open position and/or detached from the closure member  10538 , further to the above, tissue can be positioned intermediate the anvil  10508  and the staple cartridge  10506 . Thereafter, referring to  FIGS.  90  and  91   , the anvil  10508  can be moved into its closed position by rotating the input shaft  10510  in an opposite direction, i.e., direction A′, which will rotate the closure shaft  10530  in an opposite direction, i.e., direction C′, in order to move the closure nut  10536 , the closure member  10538 , and the anvil  10508  proximally. The input shaft  10510  will also rotate intermediate shaft  10520  in an opposite direction, i.e., direction B′, when the input shaft  10510  is rotated in direction A′. When the intermediate shaft  10520  is rotated in direction B′, the intermediate shaft  10520  will displace the shifter block  10526  and the slider gear  10516  distally. The shifter block  10526  can push the slider gear  10516  distally until the slider gear  10516  is no longer meshingly engaged with the closure gear  10532  and the slider gear  10516  has been returned to its idle position. Additional rotation of the intermediate shaft  10520  in direction B′ will cause the shifter block  10526  to displace the slider gear  10516  distally until the slider gear  10516  is meshingly engaged with the firing gear  10542 . At such point, referring to  FIGS.  92  and  93   , the input shaft  10510  can directly drive the firing shaft  10540 . Thereafter, the input shaft  10510  can rotate the firing shaft  10540  in direction D′ when the input shaft  10510  is rotated in direction A′. The firing system can further comprise a firing nut  10546  including a threaded aperture  10547  which is threadably engaged with a threaded portion  10544  of the firing shaft  10540 . When the firing shaft  10410  is rotated in direction A′, the firing shaft  10540  can advance the firing nut  10546  distally. The firing nut  10546  can include one or more anti-rotation features which can be slidably engaged with the frame of the surgical instrument such that the firing nut  10546  does not rotate with the firing shaft  10540  and such that rotational movement of the firing shaft  10540  can be converted to longitudinal movement of the firing nut  10546 . The firing drive can further include a firing member  10548  extending from the firing nut  10546  which is advanced distally to eject staples from the staple cartridge  10506 . Throughout the firing stroke of the firing system, the shifter block  10526  can continue to advance the slider gear  10516  distally. The firing stroke can be completed when the shifter block  10526  advances slider gear  10516  distally to the point in which the slider gear  10516  is no longer threadably engaged with the firing gear  10542 . At such point, the firing member  10548  may be in its fully fired position. 
     Further to the above,  FIG.  93    depicts the transmission  10502  in a firing configuration, i.e., a configuration in which the firing member  10548  can be advanced or retracted. When the slider gear  10516  is meshingly engaged with the firing gear  10542 , the input shaft  10510  will directly drive the firing shaft  10540 . Concurrently, the input shaft  10510  will directly drive the intermediate shaft  10520  owing to the meshing engagement between the input gear  10512  and the intermediate gear  10522 . Also, when the slider gear  10516  is meshingly engaged with the firing gear  10542 , the slider gear  10516  is not meshingly engaged with the closure gear  10532  and, as such, the input shaft  10510  will not drive the closure shaft  10530  when the transmission  10502  is in the firing configuration. 
     In order to retract the firing member  10548 , the input shaft  10510  can be rotated in direction A to rotate intermediate shaft  10520  in direction B, displace the shifter block  10526  proximally, and re-engage the slider gear  10516  with the firing gear  10542 . At such point, the continued rotation of input shaft  10510  in direction A will rotate the firing shaft  10540  in an opposite direction to direction D′, displace the firing nut  10546  proximally, and retract the firing member  10548 . As the slider gear  10516  is rotating the firing gear  10542 , the shifter block  10526  can continue to pull the slider gear  10516  proximally until the slider gear  10516  is no longer meshingly engaged with the firing gear  10542  and the slider gear  10516  reaches its idle position. At such point, the continued rotation of input shaft  10510  in direction A will continue to displace the shifter block  10526  and the slider gear  10516  proximally and re-engage the slider gear  10516  with the closure gear  10532  in order to re-open the anvil  10508 . 
       FIGS.  94 - 98    illustrates a surgical instrument  11010  configured to staple and/or incise tissue. Surgical instrument  11010  can include a pistol-grip shaped handle  11015 . Handle  11015  includes a first handle portion  11020  defining a longitudinal axis  11030  from which jaws  11070  and  11090  can extend. Handle  11015  includes a second handle portion, i.e., handle grip  11040 , which defines a second portion axis  11050 . Second portion axis  11050  defines an angle  11060  with longitudinal axis  11030 . In various instances, angle  11060  can comprise any suitable angle, such as about 120 degrees, for example. The jaw  11070  can comprise a cartridge channel including an opening configured to removably receive a staple cartridge  11080 . The staple cartridge  11080  can include a plurality of staples removably stored within staple cavities arranged in at least two longitudinal rows, one on either side of a channel in which a knife for transecting tissue can travel, as described in greater detail below. In at least on instance, three longitudinal rows of staple cavities can be arranged on a first side of the knife channel while three longitudinal rows of staple cavities can be arranged on a second side of the knife channel. The jaw  11090  can comprise an anvil rotatable to a position in opposition to and alignment with the staple cartridge  11080  so that anvil pockets defined in the anvil  11090  can receive and form staples ejected from the staple cartridge  11080 .  FIG.  98    depicts the anvil  11090  in an open position while  FIG.  94    depicts the anvil  11090  in a closed position. Although not illustrated, other embodiments are envisioned in which the jaw including the staple cartridge  11080  is rotatable relative to the anvil  11090 . In any event, as will be described in greater detail below, the handle  11015  can further include a closure button  11065  ( FIG.  98   ) configured to operate a closure system which moves the anvil  11090  between its open and closed positions and a firing button  11055  configured to operate a firing system which ejects the staples from the staple cartridge  11080 . The closure button  11065  can be positioned and arranged on the handle  11015  such that it can be easily accessed by the thumb of the operator&#39;s hand which is supporting the handle  11015 , for example, while the firing button  11055  can be positioned and arranged such that it can be easily accessed by the index finger of the operator&#39;s handle which is supporting the handle  11015 . 
     Further to the above, the anvil  11090  can be moved toward and away from the staple cartridge  11080  during use. In various instances, the closure button  11065  can include a bi-directional switch. When the closure button  11065  is depressed in a first direction, the closure system of the surgical instrument  11010  can move the anvil  11090  toward the staple cartridge  11080  and, when the closure button  11065  is depressed in a second direction, the closure system can move the anvil  11090  away from the staple cartridge  11080 . Referring primarily to  FIGS.  95  and  97   , the closure system can include a closure motor  11110  configured to move the anvil  11090 . The closure motor  11110  can include a rotatable closure shaft  11130  extending therefrom to which a first closure gear  11140  can be affixed. The closure motor  11110  can rotate the closure shaft  11130  and the closure shaft  11130  can rotate the first closure gear  11140 . The first closure gear  11140  can be meshingly engaged with an idler gear  11150  which, in turn, can be meshingly engaged with a closure lead screw drive gear  11160 . Closure lead screw drive gear  11160  is affixed to a closure lead screw  11170 . When the first closure gear  11140  is rotated by the closure shaft  11130 , the first closure gear  11140  can rotate the idler gear  11150 , the idler gear  11150  can rotate the closure lead screw drive gear  11160 , and the closure lead screw drive gear  11160  can rotate the closure lead screw  11170 . 
     Referring primarily to  FIG.  97   , the closure shaft  11130 , the first closure gear  11140 , the idler gear  11150 , and the closure lead screw drive gear  11160  can be rotatably supported by a motor block  11125  supported within the handle portion  11120 . The closure lead screw  11170  can include a first end which is also rotatably supported by the motor block  11125  and/or a second end which is rotatably supported by the housing of the handle  11015 . The closure lead screw  11170  can further comprise a threaded portion intermediate the first end and the second end. The closure system can further comprise a closure block  11175  ( FIG.  96   ) which can include a threaded aperture  11176  which is threadably engaged with the threaded portion of the closure lead screw  11170 . The closure block  11175  can be constrained from rotating with the closure lead screw  11170  such that, when the closure lead screw  11170  is rotated, the closure lead screw  11170  can displace the closure block  11175  proximally or distally, depending on the direction in which the closure lead screw  11170  is being rotated. For instance, if the closure lead screw  11170  is rotated in a first direction, the closure lead screw  11170  can displace the closure block  11175  distally and, when the closure lead screw  11170  is rotated in a second, or opposite, direction, the closure lead screw  11170  can displace the closure block  11175  proximally. Referring primarily to  FIG.  96   , the closure block  11175  can be mounted to a latch member in the form of closure channel  11180 , which translates along the outside of cartridge channel  11170 . In various instances, the closure channel  11180  can be enclosed within the handle portion  11120  while, in some instances, the closure channel  11180  can protrude from the handle portion  11120 . Closure channel  11180  can comprise an approximately “U” shaped channel when viewed from the end and can include opposing sidewalls  11182 . Each sidewall  11182  can include a cam slot  11190  defined therein. As described in greater detail further below, the cam slots  11190  can be configured to engage the anvil  11090  and move the anvil  11090  relative to the staple cartridge  11080 . 
     Further to the above, the closure channel  11180  fits around the cartridge channel  11070  so that cartridge channel  11070  nests inside the “U” shape of the closure channel  11180 . Referring primarily to  FIG.  96   , the cartridge channel  11070  can include elongated slots  11195  defined therein and the closure channel  11180  can include pins which extend inwardly into the elongated slots  11195 . The closure channel pins and the elongated slots  11195  can constrain the movement of the closure channel  11180  such that closure channel  11180  translates relative to the cartridge channel  11070  along a longitudinal path. The translational movement of the closure channel  11180  can rotate the anvil  11090 . The anvil  11090  can be connected to the closure channel  11180  via a distal closure pin  11210  which extends through anvil cam holes  11211  defined in the anvil  11090  and the cam slots  11190  defined in the closure channel  11180 . Each cam slot  11190  can include a first, or distal, end  11191  and a second, or proximal, end  11192 . Each cam slot  11190  can further include a first, or proximal, drive surface  11193  and a second, or distal, drive surface  11194 . When the closure system is in its open configuration and the anvil  11090  is in its open position, the closure channel  11180  can be in its first, or unadvanced, position and the distal closure pin  11210  can be in the first, or distal, ends  11191  of the cam slots  11190 . When the closure channel  11180  is advanced distally to move the anvil  11090  toward the staple cartridge  11080 , the first drive surface  11193  can contact the distal closure pin  11210  and push the distal closure pin  11210  downwardly toward the staple cartridge  11080 . When the closure system is in its closed configuration and the anvil  11090  is in its closed position opposite the staple cartridge  11080 , the closure channel  11180  can be in its second, or completely advanced, position and the distal closure pin  11210  can be in the second, proximal ends  11192  of the cam slots  11190 . 
     Each cam slot  11190  can comprise a curved, or arcuate, path. The first drive surface  11193  can comprise a first arcuate surface and the second drive surface  11194  can comprise a second arcuate surface. In various instances, each cam slot  11190  can include at least one curved portion and at least linear portion. In at least one instance, each first drive surface  11193  can comprise a flat surface in a distal end  11191  of a cam slot  11190 . The flat surface can comprise a vertical surface which is perpendicular to, or at least substantially perpendicular to, the longitudinal axis  11030  of the instrument  11010 . Such a flat surface can act as a detent which would require an initial amount of force to displace the closure pin  11210  into the arcuate portion of the cam slot  11190 . In certain instances, each first drive surface  11193  can comprise a flat surface  11196  in a proximal end  11192  of a cam slot  11190 . Each flat surface  11196  can comprise a horizontal surface which is parallel to, or at least substantially parallel to, the longitudinal axis  11030 . The flat surfaces  11196  can provide a large mechanical advantage between the closure channel  11180  and the anvil  11090 . In various instances, the first drive surfaces  11193  can apply very little mechanical advantage to the closure pin  11210  when the closure pin  11210  is in the distal ends  11191  of the slots  11190 ; however, as the closure pin  11210  slides through the cam slots  11190  toward the proximal ends  11192 , the mechanical advantage applied to the closure pin  11210  by the first drive surfaces  11193  can increase. When the closure pin  11210  enters into the proximal ends  11192 , the mechanical advantage applied by the first drive surfaces  11193  can be at its greatest, and certainly larger than the mechanical advantage applied by the first drive surfaces  11193  when the closure pin  11210  is in the distal ends  11191  of the cam slots  11190 . That said, where the distal ends  11191  may apply a lower mechanical advantage to the closure pin  11210 , the distal ends  11191  may quickly displace the closure pin  11210  relative to the cartridge  11080 . As the closure channel  11180  is advanced distally and the mechanical advantage applied to the closure pin  11210  increases, as discussed above, the first drive surfaces  11193  may move the anvil  11090  more slowly for a given speed of the closure channel  11180 . 
     As illustrated in  FIG.  96   , the cartridge channel  11070  can further include distal closure slots  11215  defined therein which can be configured to receive the distal closure pin  11210  as the anvil  11090  approaches its closed position. Distal closure slots  11215  are substantially vertical and can include open ends at the top of the cartridge channel  11070  and closed ends at the opposite ends thereof. The slots  11215  may be wider at their open ends than their closed ends. In various instances, the closure pin  11210  can contact the closed ends of the closure slots  11215  when the anvil  11090  reaches its closed position. In such instances, the closed ends of the closure slots  11215  can stop the movement of the anvil  11090 . In certain instances, the anvil  11090  can contact the staple cartridge  11080  when the anvil  11090  is in its closed position. In at least one instance, the anvil  11090  can be rotated about the pivot pin  11200  until a distal end  11091  of the anvil  11090  contacts a distal end  11081  of the staple cartridge  11080 . As illustrated in  FIG.  98   , the distal closure pin  11210  which moves the anvil  11090  is positioned distally with respect to the pivot pin  11220 . Thus, the closure force applied to the anvil  11090  by the closure drive is applied distally with respect to the pivot which rotatably connects the anvil  11090  to the cartridge channel  11070 . Similarly, the opening force applied to the anvil  11090  by the closure drive is applied distally with respect to the pivot which rotatably connects the anvil  11090  to the cartridge channel  11070 . 
     As discussed above, the handle  11015  can include a closure button  11065  configured to operate the closure system of the surgical instrument  11010 . The movement of the closure button  11065  can be detected by a sensor or a switch, for example. When the closure button  11065  is pressed, a closure switch  11285  can be activated, or closed, which causes power to flow to the closure motor  11110 . In such instances, the switch  11285  can close a power circuit which can supply electrical power to the closure motor  11110 . In certain instances, the surgical instrument  11010  can include a microprocessor, for example. In such instances, the closure switch  11285  can be in signal communication with the microprocessor and, when the closure switch  11285  has been closed, the microprocessor can operably connect a power supply to the closure motor  11110 . In any event, a first voltage polarity can be applied to the closure motor  11110  to rotate the closure output shaft  11130  in a first direction and close the anvil  11090  and, in addition, a second, or opposite, voltage polarity can be applied to closure motor  11110  to rotate the closure output shaft  11130  in a second, or opposite, direction and open the anvil  11090 . 
     In various instances, the surgical instrument  11010  may be configured such that the operator of the surgical instrument  11010  is required to hold the closure button  11065  in a depressed state until the closure drive has reached its fully closed configuration. In the event that the closure button  11065  is released, the microprocessor can stop the closure motor  11110 . Alternatively, the microprocessor can reverse the direction of the closure motor  11110  if the closure button  11065  is released prior to the closure drive reaching its fully closed configuration. After the closure drive has reached its fully closed configuration, the microprocessor may stop the closure motor  11110 . In various instances, as described in greater detail below, the surgical instrument  11010  can comprise a closure sensor  11300  ( FIGS.  96  and  98   ) configured to detect when the closure system has reached its fully closed configuration. The closure sensor  11300  can be in signal communication with the microprocessor which can disconnect the power supply from the closure motor  11110  when the microprocessor receives a signal from the closure sensor  11300  that the anvil  11090  has been closed. In various instances, re-pressing the closure button  11065  after the closure system has been placed in its closed configuration, but before the firing system has been operated, can cause the microprocessor to reverse the direction of the closure motor  11110  and re-open the anvil  11090 . In certain instances, the microprocessor can re-open the anvil  11090  to its fully open position while, in other instances, the microprocessor can re-open the anvil  11090  to a partially open position. 
     Once the anvil  11090  has been sufficiently closed, the firing system of the surgical instrument  11010  can be operated. Referring primarily to  FIGS.  95  and  97   , the firing system can include a firing motor  11120 . The firing motor  11120  can be positioned adjacent to the closure motor  11110 . The closure motor  11110  can extend along a first longitudinal motor axis and the firing motor  11120  can extend along a second longitudinal motor axis which is parallel, or at least substantially parallel to the first motor axis. The first longitudinal motor axis and the second longitudinal motor axis can be parallel to the longitudinal axis  11030  of the surgical instrument  11010 . The closure motor  11110  can be positioned on a first side of the longitudinal axis  11030  and the firing motor  11120  can be positioned on a second side of the longitudinal axis  11030 . In such instances, the first longitudinal motor axis can extend along a first side of the longitudinal axis  11030  and the second longitudinal motor axis can extend along a second side of the longitudinal axis  11030 . In various instances, the first longitudinal motor axis can extend through the center of the closure shaft  11130 . Similar to the above, the firing motor  11120  can include a rotatable firing shaft  11230  extending therefrom. Also similar to the above, the second longitudinal motor axis can extend through the center of the firing shaft  11230 . 
     Further to the above, a first firing gear  11240  can be mounted to the firing shaft  11230 . The first firing gear  11240  is meshingly engaged with a firing lead screw drive gear  11250  which is mounted to a firing lead screw  11260 . When the firing shaft  11230  is rotated by the motor  11120 , the firing shaft  11230  can rotate the first firing gear  11240 , the first firing gear  11240  can rotate the firing lead screw drive gear  11250 , and the firing lead screw drive gear  11250  can rotate the firing lead screw  11260 . Referring primarily to  FIG.  97   , the firing shaft  11230 , the first firing gear  11240 , the firing lead screw drive gear  11250 , and/or the firing lead screw  11260  can be rotatably supported by the motor block  11125 . The first firing gear  11240  and the firing lead screw drive gear  11250  can be positioned intermediate the motor block  11125  and a first block plate  11126 . The first block plate  11126  can be mounted to the motor block  11125  and can also rotatably support the firing shaft  11230 , the first firing gear  11240 , the firing lead screw drive gear  11250 , and/or the firing lead screw  11260 . In various instances, the surgical instrument  11010  can further comprise a second block plate  11127  which can be mounted to the first block plate  11126 . Similar to the above, the first closure gear  11140 , the idler gear  11150 , and the closure lead screw drive gear  11160  can be positioned intermediate the first block plate  11126  and the second block plate  11127 . In various instances, the first block plate  11126  and/or the second block plate  11127  can rotatably support the closure shaft  11130 , the first closure gear  11140 , the idler gear  11150 , the closure lead screw drive gear  11160 , and/or the closure lead screw  11170 . 
     The motor and gear arrangement described above can aid in conserving space within the handle  11015  of surgical instrument  11010 . As described above, and referring primarily to  FIG.  97   , the closure motor  11110  and the firing motor  11120  are located on the motor block  11125 . The closure motor  11110  is located on one side and slightly proximally of the firing motor  11120 . Offsetting one motor proximally from another creates space for two gear trains with one gear train behind the other. For example, the closure gear train comprising the first closure gear  11140 , the closure idler gear  11150 , and the closure lead screw drive gear  11160  is proximal to the firing gear train comprising the first firing gear  11240  and the firing lead screw drive gear  11250 . Having motor shafts extend proximally away from the jaws, with the main body of the motor extending distally toward the jaws, creates room in the handle  11015  and allows a shorter handle  11015  by having the main body of the motors  11110  and  11120  aligned parallel alongside other parts within the handle  11015 . 
     Further to the above, the closure and firing gear trains are designed for space conservation. In the embodiment depicted in  FIG.  97   , the closure motor  11110  drives three gears, while the firing motor  11120  drives two gears; however, the closure gear train and the firing gear train can include any suitable number of gears. The addition of a third gear, i.e., the closure idler gear  11150 , to the closure gear train permits the closure lead screw  11170  to be shifted downwardly with respect to the firing lead screw  11260  so that the separate lead screws can rotate about different axes. Moreover, the third gear eliminates the need for larger diameter gears to shift the axes of the lead screws so that the overall diameter of the space required by the gear trains, and the volume of the handle  11015 , can be reduced. 
     Referring primarily to  FIG.  98   , the closure lead screw  11170  can extend along a first longitudinal shaft axis and the firing lead screw  11260  can extend along a second longitudinal shaft axis. The first longitudinal shaft axis and the second longitudinal shaft axis can be parallel to the longitudinal axis  11030  of the surgical instrument  11010 . The first longitudinal shaft axis or the second longitudinal shaft axis can be collinear with the longitudinal axis  11030 . In various instances, the firing lead screw  11260  can extend along the longitudinal axis  11030  and the second longitudinal shaft axis can be collinear with the longitudinal axis  11030 . In such instances, the closing lead screw  11170  and the first longitudinal shaft axis can be offset with respect to the longitudinal axis  11030 . 
     Further to the above, the firing lead screw  11260  can include a first end rotatably supported by the motor block  11125 , for example, a second end rotatably supported by the handle  11015 , and a threaded portion extending between the first end and the second end. The firing lead screw  11260  can reside within the “U” shape of the cartridge channel  11070  and above the closure lead screw  11170 . Referring primarily to  FIG.  95   , the firing drive can further comprise a firing block  11265  which can include a threaded aperture  11266  threadably engaged with the threaded portion of the firing lead screw  11260 . The firing block  11265  can be constrained from rotating with the firing lead screw  11260  such that the rotation of the firing lead screw  11260  can translate the firing block  11265  proximally or distally depending on the direction that the firing lead screw  11260  is rotated by the firing motor  11120 . For instance, when the firing lead screw  11260  is rotated in a first direction, the firing lead screw  11260  can displace the firing block  11265  distally and, when the firing lead screw  11260  is rotated in a second direction, the firing lead screw  11260  can displace the firing block  11265  proximally. As described in greater detail below, the firing block  11265  can be advanced distally to deploy staples removably stored in the staple cartridge  11080  and/or incise tissue captured between the staple cartridge  11080  and the anvil  11090 . 
     Further to the above, the firing block  11265  can be affixed to a pusher block  11270  such that the pusher block  11270  translates with the firing block  11265 . The firing system can further include firing wedges  11280  which are attached to and extend distally from the pusher block  11270 . The firing wedges  11280  can each include at least one cam surface at a distal end thereof which can be configured to eject staples from the staple cartridge  11080 . The firing system can further comprise a knife block  11281  slidably disposed along the firing wedges  11280 . In various instances, the initial distal movement of the firing block  11265  may not be transferred to the knife block  11281 ; however, as the firing block  11265  is advanced distally, the pusher block  11270 , for example, can contact the knife block  11281  and push the knife block  11281  and a knife  11282  mounted thereto distally. In other instances, the knife block  11281  can be mounted to the firing wedges  11280  such that the knife block  11281  and the knife  11282  move with the firing wedges  11280  throughout the movement of the firing wedges  11280 . The firing block  11265 , the pusher block  11270 , the firing wedges  11280 , the knife block  11281 , and the knife  11282  can form a pusher block and knife assembly. In any event, the firing wedges  11280  and the knife  11282  can be moved distally to simultaneously fire the staples stored within the staple cartridge  11080  and incise the tissue captured between the staple cartridge  11080  and the anvil  11090 . The cam surfaces of the firing wedges  11280  can be positioned distally with respect to the cutting surface of the knife  11282  such that the tissue captured between the staple cartridge  11080  and the anvil  11090  can be stapled before it&#39;s incised. 
     As discussed above, the closure button  11065 , when pushed, contacts the closure switch  11285  to energize closure motor  11110 . Similarly, the firing button  11055 , when pushed, contacts a firing switch  11290  to energize the firing motor  11120 . In various instances, the firing switch  11290  can close a power circuit which can supply electrical power to the firing motor  11120 . In certain instances, the firing switch  11290  can be in signal communication with the microprocessor of the surgical instrument  11010  and, when the firing switch  11290  has been closed, the microprocessor can operably connect a power supply to the firing motor  11120 . In either event, a first voltage polarity can be applied to the firing motor  11120  to rotate the firing output shaft  11230  in a first direction and advance the firing assembly distally and a second, or opposite, voltage polarity can be applied to firing motor  11120  to rotate the firing output shaft  11230  in a second, or opposite, direction and retract the firing assembly. In various instances, the firing button  11055  can include a bi-directional switch configured to operate the firing motor  11120  in its first direction when the firing button  11055  is pushed in a first direction and in its second direction when the firing button  11055  is pushed in a second direction. 
     As discussed above, the firing system can be actuated after the closure system has sufficiently closed the anvil  11090 . In various instances, the anvil  11090  may be sufficiently closed when it has reached its fully closed position. The surgical instrument  11010  can be configured to detect when the anvil  11090  has reached its fully closed position. Referring primarily to  FIG.  98   , the surgical instrument  11010  can include a closure sensor  11300  configured to detect when the closure channel  11180  has reached the end of its closure stroke and, thus, detect when the anvil  11090  is in its closed position. The closure sensor  11300  can be positioned at or adjacent to the distal end of the closure lead screw  11170 . In at least one instance, the closure sensor  11300  can comprise a proximity sensor configured to sense when the closure channel  11180  is adjacent to and/or in contact with the closure sensor  11300 . Similar to the above, the closure sensor  11300  can be in signal communication with the microprocessor of the surgical instrument  11010 . When the microprocessor receives a signal from the closure sensor  11300  that the closure channel  11180  has reached its fully advanced position and the anvil  11090  is in a closed position, the microprocessor can permit the firing system to be actuated. Moreover, the microprocessor can prevent the firing system from being actuated until the microprocessor receives such a signal from the closure sensor  11300 . In such instances, the microprocessor can selectively apply power from a power source to the firing motor  11120 , or selectively control the power being applied to the firing motor  11120 , based on the input from the closure sensor  11300 . Ultimately, in these embodiments, the firing switch  11290  cannot initiate the firing stroke until the instrument is closed. 
     Certain embodiments are envisioned in which the firing system of the surgical instrument  11010  can be operated even though the closure system is in a partially closed configuration and the anvil  11090  is in a partial closed position. In at least one embodiment, the firing assembly of the surgical instrument  11010  can be configured to contact the anvil  11090  and move the anvil  11090  into its fully closed position as the firing assembly is advanced distally to fire the staples stored in the staple cartridge  11080 . For instance, the knife  11282  can include a camming member configured to engage the anvil  11090  as the knife  11282  is advanced distally which can move the anvil  11090  into its fully closed position. The knife  11282  can also include a second camming member configured to engage the cartridge channel  11070 . The camming members can be configured to position the anvil  11090  relative to the staple cartridge  11080  and set a tissue gap distance therebetween. In at least one instance, the knife  11282  can comprise an I-beam which is displaced distally to set the tissue gap, eject the staples from the staple cartridge  11080 , and incise the tissue. 
     The surgical instrument  11010  can a sensor configured to detect when the firing system has completed its firing stroke. In at least one instance, the surgical instrument  11010  can include a sensor, such as an encoder, for example, which can be configured to detect and count the rotations of the firing lead screw  11260 . Such a sensor can be in signal communication with the microprocessor of the surgical instrument  11010 . The microprocessor can be configured to count the rotations of the firing lead screw  11260  and, after the firing lead screw  11260  has been rotated a sufficient number of times to fire all of the staples from the staple cartridge  11080 , the microprocessor can interrupt the power supplied to the firing motor  11120  to stop the firing lead screw  11260 . In certain instances, the microprocessor can reverse the voltage polarity applied to the firing motor  11120  to automatically retract the firing assembly once the firing assembly has fired all of the staples. 
     As discussed above, the surgical instrument  11010  can include a power supply. The power supply can include a power supply located external to the handle  11015  and a cable which can extend into the handle  11015 , for example. The power supply can include at least one battery contained within handle  11015 . A battery can be positioned in the first handle portion  11020  and/or the handle grip  11040 . It is envisioned that the batteries, gears, motors, and rotating shafts may all be combined in one unit separable from the rest of handle  11015 . Such a unit may be cleanable and sterilizable. 
     In various instances, the surgical instrument  11010  can include one or more indicators configured to indicate the state of the surgical instrument  11010 . In at least one embodiment, the surgical instrument  11010  can include an LED  11100 , for example. To communicate the state of the surgical instrument to the user, the LED  11100  can glow in different colors during different operating states of surgical instrument  11010 . For example, the LED  11100  can glow a first color when the surgical instrument  11010  is powered and an unspent staple cartridge  11080  is not positioned in the cartridge channel  11070 . The surgical instrument  11010  can include one or more sensors which can be configured to detect whether a staple cartridge  11080  is present in the cartridge channel  11070  and whether staples have been ejected from the staple cartridge  11080 . The LED  11100  can glow a second color when the surgical instrument  11010  is powered and an unspent staple cartridge  11080  is positioned in the cartridge channel  11070 . The LED  11010  can glow a third color when the instrument  11010  is powered, an unspent staple cartridge  11080  is loaded into the cartridge channel  11070 , and the anvil  11090  is in a closed position. Such a third color can indicate that the surgical instrument  11010  is ready to fire the staples from the staple cartridge  11080 . The LED  11100  can glow a fourth color after the firing process has begun. The LED can glow a fifth color after the firing process has been completed. This is but one exemplary embodiment. Any suitable number of colors could be utilized to indicate any suitable number of states of the surgical instrument  11010 . While one or more LEDs may be utilized to communicate the state of the surgical instrument, other indicators could be utilized. 
     In use, a user of the surgical instrument  11010  may first load the surgical instrument  11010  with a staple cartridge  11080  by placing the staple cartridge  11080  into the cartridge channel  11070 . Loading the cartridge  11080  into the cartridge channel  11070  may cause the LED  11100  to change from a first color to a second color. The user may grasp the handle grip  11040  and use the thumb activated closure switch  11065  to open the anvil  11090  of the surgical instrument  11010  in order to place the staple cartridge  11080  within the cartridge channel  11070 . The user could then position the staple cartridge  11080  on one side of the tissue to be stapled and transected and the anvil  11090  on the opposite side of the tissue. Holding closure button  11065  with their thumb, the user may close surgical instrument  11010 . Release of the closure button  11065  before the closing stroke is completed can reopen the anvil  11090  and allow the user to reposition the surgical instrument  11010 , if necessary. The user may enjoy the advantage of being able to use an open linear cutter with pivotable jaws without the necessity of assembling linear cutter portions. The user may further enjoy the advantage of a pistol-grip feel. 
     As the anvil  11090  is being moved into its fully closed position, the closure channel  11080  can contact the closure sensor  11300 , and the closure sensor  11300  can signal the microprocessor to arm firing switch  11290 . At such point, the LED  11100  may glow a third color to show a loaded, closed, and ready-to-fire surgical instrument  11010 . The user can then press the firing button  11055  which contacts the firing switch  11290  and causes the firing switch  11290  to energize the firing motor  11120 . Energizing the firing motor  11120  rotates the firing shaft  11230  which, in turn, rotates the first firing gear  11240  and the firing lead screw drive gear  11250 . The firing lead screw drive gear  11250  rotates the firing lead screw  11260 . Threads of the firing lead screw  11260  engage and apply a force against internal threads defined in the firing block  11265  to move the firing block  11265  distally. The firing block  11265  moves pusher block  11270  distally, carrying firing wedges  11280  distally. The cam surfaces  11305  at the distal end of the firing wedges  11280  cam staples stored within the staple cartridge  11080  toward the anvil  11090 , and the anvil  11090  can form the staples to fasten the tissue. The pusher block  11270  engages the knife block  11281  to push the knife block  11281  and the knife  11282  distally to transect the stapled tissue. After the firing stroke has been completed, the firing motor  11120  can be reversed to return the pusher block  11270 , the knife block  11281 , the firing wedges  11280 , and the knife  11282 . The surgical instrument  11010  can include a button and/or switch which automatically instructs the microprocessor to retract the firing assembly even though the firing stroke has not yet been completed. In some instances, the firing assembly may not need to be retracted. In any event, the user can open the surgical instrument  11010  by pressing the closure button  11065 . The closure button  11065  can contact the closure switch  11285  and energize the closure motor  11110 . The closure motor  11110  can be operated in a reverse direction to retract the closure channel  11180  proximally to reopen the anvil  11090  of the surgical instrument  11010 . The LED  11100  may glow a fourth color designating a fired cartridge, and a complete procedure. 
     A surgical stapling instrument  12010  is depicted in  FIGS.  99 - 106   . The instrument  12010  can include a handle  12015 , a closure drive including a closure latch  12050  configured to compress tissue between a staple cartridge  12080  and an anvil  12090 , and a firing drive configured to eject staples from the staple cartridge  12080  and incise the tissue.  FIG.  99    depicts the instrument  12010  in an open, unlatched condition. When the instrument  12010  is in its open, unlatched condition, the anvil  12090  is pivoted away from the staple cartridge  12080 . In various instances, the anvil  12090  can be pivoted relative to the staple cartridge  12080  through a wide angle so that the anvil  12090  and the staple cartridge  12080  may be easily positioned on opposite sides of the tissue.  FIG.  100    depicts the instrument  12010  in a closed, unlatched condition. When the instrument  12010  is in its closed, unlatched condition, the anvil  12090  has been rotated toward the staple cartridge  12080  into a closed position opposite the staple cartridge  12080 . In various instances, the closed position of the anvil  12090  may depend on the thickness of the tissue positioned intermediate the anvil  12090  and the staple cartridge  12080 . For instance, the anvil  12090  may reach a closed position which is further away from the staple cartridge  12080  when the tissue positioned intermediate the anvil  12090  and the staple cartridge  12080  is thicker as compared to when the tissue is thinner.  FIG.  101    depicts the instrument  12010  in a closed, latched condition. When the instrument  12010  is in its closed, latched condition, the closure latch  12050  has been rotated to engage the anvil  12090  and position the anvil  12090  relative to the staple cartridge  12080 . At such point, as described in greater detail further below, the firing drive of the surgical instrument  12010  can be actuated to fire the staples from the staple cartridge  12080  and incise the tissue. 
     Referring primarily to  FIG.  106   , the surgical instrument  12010  can include a frame  12020  extending from the handle  12015 . The frame  12020  can include a frame channel  12022  defined therein which can be configured to receive and/or support a cartridge channel  12070 . The cartridge channel  12070  can include a proximal end and a distal end. The proximal end of the cartridge channel  12070  can be connected to the frame  12020 . The distal end of the cartridge channel  12070  can be configured to removably receive a staple cartridge  12080  therein. The frame channel  12022  can include pivot apertures  12207  defined in opposite sides thereof. A pivot pin  12205  can be supported within the pivot apertures  12207  and can extend between the sides of the channel  12022 . The closure latch  12050  can include a latch frame  12051  comprising latch bars  12052 . The latch bars  12052  can be rotatably mounted to the frame  12020  via the pivot pin  12205  which can extend through pivot apertures  12206  defined in the latch bars  12052 . In various instances, the pivot apertures  12206 ,  12207  and the pivot pin  12205  can define a fixed axis  12208  about which the closure latch  12050  can rotate. The closure latch  12050  can further include a latch housing  12057  mounted to the latch bars  12052 . When the latch housing  12057  is moved by the user of the surgical instrument  12010 , the latch housing  12057  can move the latch bars  12052 . The operation of the closure latch  12050  is described in greater detail further below. 
     Further to the above, the anvil  12090  can include a proximal end and a distal end. The distal end of the anvil  12090  can include a plurality of staple forming pockets which are alignable, or registerable, with staple cavities defined in the staple cartridge  12080  when the anvil  12090  is in its closed position. The proximal end of the anvil  12090  can be pivotably connected to the frame  12020 . The anvil  12090  can include a pivot aperture  12201  which can be aligned with pivot apertures  12202  defined in the cartridge channel  12207  and a pivot aperture  12203  defined in the frame  12020 . A pivot pin  12200  can extend through the pivot apertures  12201 ,  12202 , and  12203  and can rotatably connect the anvil  12090  to the cartridge channel  12207 . In various instances, the pivot apertures  12201 ,  12202 , and  12203  and the pivot pin  12200  can define a fixed axis about the anvil  12090  can rotate. In certain instances, the pivot apertures  12201 ,  12202  and/or  12203  can be longitudinally elongate, for example, such that the pivot pin  12200  can slide within the pivot apertures  12201 ,  12202  and/or  12203 . In such instances, the anvil  12090  can rotate about an axis relative to the cartridge channel  12070  and, in addition, translate relative to the cartridge channel  12070 . The anvil  12090  can further include an anvil housing  12097  mounted thereto. When the anvil housing  12097  is moved by the user of the surgical instrument  12010 , the anvil housing  12097  can move the anvil  12090  such that the anvil  12090  can be rotated between an open position ( FIG.  99   ) and a closed position ( FIG.  100   ). 
     Further to the above, the anvil  12090  can further include a latch pin  12210 . The anvil  12090  can include latch pin apertures  12211  and the anvil housing  12097  can include latch pin apertures  12212  which are configured to receive and support the latch pin  12210 . When the anvil  12090  has been moved into its closed position, or a position adjacent to its closed position, the latch  12050  can engage the latch pin  12210  and pull the anvil  12090  toward the staple cartridge  12080 . In various instances, the latch bars  12052  of the latch  12050  can each include a latch arm  12053  configured to engage the latch pin  12210 . The latch  12050  can be rotated between an unlatched position ( FIG.  100   ) in which the latch arms  12053  are not engaged with the latch pin  12210  and a latched position ( FIG.  101   ). When the latch  12050  is moved between its unlatched position and its latched position, the latch arms  12053  can engage the latch pin  12210  and move the anvil  12090  toward the staple cartridge  12080 . Each latch arm  12053  can include a camming surface configured to contact the latch pin  12210 . The camming surfaces can be configured to push and guide the latch pin  12210  toward the staple cartridge  12080 . When the latch  12050  has reached its latched position, the latch pin  12210  can be captured within latch slots  12054  defined in the latch bars  12052 . The latch slots  12054  can be at least partially defined by the latch arms  12053 . The opposite sides of the latch slots  12054  can include lift surfaces which can be configured to engage the latch pin  12210  and lift the anvil  12090  away from the staple cartridge  12080  when the latch  12050  is rotated between its latched position and its unlatched position to open the instrument  12010 , as discussed in greater detail further below. 
     As discussed above, the anvil  12090  can be moved toward the staple cartridge  12080 . In various instances, the movement of the anvil  12090  toward the staple cartridge  12080  can be stopped when a distal end of the anvil  12090  contacts a distal end of the staple cartridge  12080 . In certain instances, the movement of the anvil  12090  can be stopped when the latch pin  12210  contacts the cartridge channel  12070 . The cartridge channel  12070  can include slots  12215  defined therein which are configured to receive the latch pin  12210 . Each slot  12215  can include an upwardly-facing open end through which the latch pin  12210  can enter the slot  12215  and, in addition, a closed end. In various instances, the latch pin  12210  can contact the closed ends of the slots  12215  when the anvil  12090  reaches its closed position. In certain instances, the latch pin  12210  may not contact the closed ends of the slots  12215  if thick tissue is positioned between the anvil  12090  and the staple cartridge  12080 . In at least one instance, the anvil  12090  can further include a stop pin  12095 . The stop pin  12095  can be mounted to and supported by the anvil  12090  via pin apertures  12096  defined therein. The stop pin  12095  can be configured to contact the cartridge channel  12070  and stop the movement of the anvil  12090  toward the staple cartridge  12080 . Similar to the above, the cartridge channel  12070  can further include stop slots  12075  defined therein which can be configured to receive the stop pin  12095 . Each stop slot  12075  can include an upwardly-facing open end through which the stop pin  12095  can enter the stop slot  12275  and, in addition, a closed end. In various instances, the stop pin  12095  can contact the closed ends of the stop slots  12075  when the anvil  12090  reaches its closed position. In certain instances, the stop pin  12095  may not contact the closed ends of the stop slots  12075  if thick tissue is positioned between the anvil  12090  and the staple cartridge  12080 . 
     As discussed above, the cartridge channel  12070  can be mounted to the frame  12020 . In various instances, the cartridge channel  12070  can be rigidly and fixedly mounted to the frame  12020 . In such instances, the cartridge channel  12070  may not be movable relative to the frame  12020  and/or the handle  12015 . In certain instances, the cartridge channel  12070  can be pivotably coupled to the frame  12020 . In at least one such instance, the cartridge channel  12070  can include pivot apertures  12202  defined therein which can be configured to receive the pivot pin  12200 . In such circumstances, both the anvil  12090  and the cartridge channel  12070  may be rotatable relative to the frame  12020  about the pivot pin  12200 . The latch  12050  can hold the anvil  12090  and the cartridge channel  12070  in position when the latch  12050  is engaged with the latch pin  12210 . 
     In certain instances, further to the above, the instrument  12010  can include one or more sensors configured to detect whether the anvil  12090  is in its closed position. In at least one instance, the instrument  12010  can include a pressure sensor positioned intermediate the frame  12020  and the cartridge channel  12070 . The pressure sensor can be mounted to the frame channel  12022  or the bottom of the cartridge channel  12070 , for example. When the pressure sensor is mounted to the bottom of the cartridge channel  12070 , the pressure sensor can contact the frame channel  12022  when the cartridge channel  12070  is moved toward the frame channel  12022 . The cartridge channel  12070  can be moved toward the frame channel  12022  if the cartridge channel  12070  is rotatable relative to the frame channel  12022 , as discussed above. In addition to or in lieu of the above, the cartridge channel  12070  can be moved toward the frame channel  12022  if the cartridge channel  12070  flexes toward the frame channel  12022 . The cartridge channel  12070  can flex toward the frame channel  12022  when a compressive load is generated between the anvil  12090  and the cartridge channel  12070 . A compressive load between the anvil  12090  and the cartridge channel  12070  can be generated when the anvil  12090  is moved into its closed position and/or when the anvil  12090  is moved toward the cartridge channel  12070  by the latch  12050 . When the anvil  12090  is pushed toward the cartridge channel  12070  and/or when the latch  12050  is used to pull the anvil  12090  toward the cartridge channel  12070 , the cartridge channel  12070  can bear against the pivot pin  12205 . In various instances, the cartridge channel  12070  can include a slot or groove  12209  defined therein which can be configured to receive the pivot pin  12205 . In any event, the pressure sensor can be configured to detect the pressure or force being applied to the cartridge channel  12070 . The pressure sensor can be in signal communication with a microprocessor of the surgical instrument  12010 . When the pressure or force detected by the pressure sensor exceeds a threshold value, the microprocessor can permit the firing system of the instrument  12010  to be operated. Prior to the pressure or force exceeding the threshold value, the microprocessor can warn the user of the surgical instrument  12010  that the anvil  12090  may not be closed, or sufficiently closed, when the user attempts to operate the firing system. In addition to or in lieu of such a warning, the microprocessor can prevent the firing system of the instrument  12010  from being operated if the pressure or force detected by the pressure sensor has not exceeded the threshold value. 
     In certain instances, further to the above, the instrument  12010  can include one or more sensors configured to detect whether the latch  12050  is in its latched position. In at least one instance, the instrument  12010  can include a sensor  12025  positioned intermediate the frame  12020  and the cartridge channel  12070 . The sensor  12025  can be mounted to the frame channel  12022  or the bottom of the cartridge channel  12070 , for example. When the sensor  12025  is mounted to the bottom of the cartridge channel  12070 , the latch  12050  can contact the sensor  12025  when the latch  12050  is moved from its unlatched position to its latched position. The sensor  12025  can be in signal communication with the microprocessor of the surgical instrument  12010 . When the sensor  12025  detects that the latch  12050  is in its latched position, the microprocessor can permit the firing system of the instrument  12010  to be operated. Prior to the sensor  12025  sensing that the latch  12050  is in its latched position, the microprocessor can warn the user of the surgical instrument  12010  that the anvil  12090  may not be closed, or sufficiently closed, when the user attempts to operate the firing system. In addition to or in lieu of such a warning, the microprocessor can prevent the firing system of the instrument  12010  from being operated if the latch  12050  is not detected in its latched position. In various instances, the sensor  12025  can comprise a proximity sensor, for example. In certain instances, the sensor  12025  can comprise a Hall Effect sensor, for example. In at least one such instance, the latch  12050  can include at least one magnetic element, such as a permanent magnet, for example, which can be detected by the Hall Effect sensor. In various instances, the sensor  12025  can be held in position by a bracket  12026 , for example. 
     Referring primarily to  FIG.  105   , the firing system of the surgical instrument  12010  can include a firing motor  12120  configured to rotate a firing shaft  12230 . The firing motor  12120  can be mounted to a motor frame  12125  within the handle  12015  of the surgical instrument  12010  such that the firing shaft  12230  extends distally. The firing system can further comprise a gear train including, one, a first firing gear  12240  mounted to the closure shaft  12230  and, two, a lead screw gear  12250  mounted to a lead screw  12260 . The first firing gear  12240  can be meshingly engaged with the lead screw gear  12250  such that, when the first firing fear  12240  is rotated by the firing shaft  12230 , the first firing gear  12240  can rotate the lead screw gear  12250  and the lead screw gear  12250  can rotate the lead screw  12260 . Referring primarily to  FIG.  104   , the lead screw  12260  can comprise a first end  12261  rotatably  12250  mounted within an aperture defined in the motor block  12125  and a second end  12263  rotatably supported within a bearing mounted to a bearing portion  12264  of the handle  12015 . The lead screw  12260  can further include a threaded portion  12262  extending between the first end  12261  and the second end  12263 . The firing system can further comprise a firing nut  12265  threadably engaged with the threaded portion  12262  of the lead screw  12260 . The firing nut  12265  can be constrained from rotating with the lead screw  12260  such that, when the lead screw  12260  is rotated in a first direction by the firing motor  12120 , the lead screw  12260  can advance the firing nut  12265  distally and, correspondingly, when the lead screw  12260  is rotated in a second, or opposite, direction by the firing motor  12120 , the lead screw  12260  can retract the firing nut  12265  proximally. 
     Further to the above, the firing nut  12265  can be mounted to a firing block  12270  which can translate with the firing nut  12265 . In various instances, the firing nut  12265  and the firing block  12270  can be integrally formed. Similar to the above, the firing system can further include firing bars  12280  extending therefrom which translate with the firing nut  12265  and the firing block  12270 . In various instances, the firing nut  12265 , the firing block  12270 , and the firing bars  12280  can comprise a firing assembly that is translated proximally and/or distally by the lead screw  12160 . When the firing assembly is advanced distally by the lead screw  12260 , the firing bars  12280  can enter into the staple cartridge  12080  and eject the staples therefrom. The firing system can further comprise a knife block  12281  and a knife bar  12282  mounted to and extending from the knife block  12281 . As the firing block  12270  is advanced distally, the firing bars  12280  can engage the knife block  12281  and advance the knife block  12281  and the knife bar  12282  distally. In various instances, the firing block  12270  can move relative to the knife block  12281  during the initial portion of the firing stroke and then move together during the final portion of the firing stroke. In at least one such instance, the firing bars  12280  can slide through slots defined in the knife block  12281  until one or more raised surfaces extending from the firing bars  12280  contact the knife block  12281  and push the knife block  12281  distally with the firing bars  12280 . In various instances, the firing assembly can further include the knife block  12281  and the knife bar  12282  which can move concurrently with the firing block  12270  and the firing bars  12280 . In either event, as the knife bar  12282  is advanced distally, a cutting edge  12283  of the knife bar  12282  can incise tissue captured between the anvil  12090  and the staple cartridge  12080 . The disclosure of U.S. Pat. No. 4,633,874, entitled SURGICAL STAPLING INSTRUMENT WITH JAW LATCHING MECHANISM AND DISPOSABLE LOADING CARTRIDGE, which issued on Jan. 6, 1987, is incorporated by reference herein in its entirety. 
     Referring primarily to  FIG.  106   , the firing system of the surgical instrument  12010  can include a firing button  12055  and a firing switch  12290 . When the user of the surgical instrument  12010  depresses the firing button  12055 , the firing button  12055  can contact the firing switch  12290  and close a firing circuit which can operate the firing motor  12120 . When the user of the surgical instrument  12010  releases the firing button  12055 , the firing circuit can be opened and the power supplied to the firing motor  12120  can be interrupted. The firing button  12055  can be pushed once again to operate the firing motor  12120  once again. In certain instances, the firing button  12055  can comprise a bi-directional switch which, when pushed in a first direction, can operate the firing motor  12120  in a first direction and, when pushed in a second direction, can operate the firing motor  12120  in a second, or opposite, direction. The firing switch  12090  and/or any suitable arrangement of firing switches can be in signal communication with the microprocessor of the surgical instrument  12010  which can be configured to control the power supplied to the firing motor  12120 . In certain instances, further to the above, the microprocessor may ignore signals from the firing button  12055  until the sensor  12025  has detected that the latch  12050  has been closed. In any event, the firing button  12055  can be pushed in its first direction to advance the firing bars  12280  and the knife  12282  distally and its second direction to retract the firing bars  12280  and the knife  12282  proximally. In certain instances, the surgical instrument  12010  can include a firing button and switch configured to operate the firing motor  12120  in its first direction and a retraction button and switch configured to operate the firing motor  12120  in its second direction. After the firing bars  12280  and the knife  12282  have been retracted, the latch  12050  can be moved from its latched position to its unlatched position to disengage the latch arms  12053  from the latch pin  12210 . Thereafter, the anvil  12090  can be pivoted away from the staple cartridge  12080  to return the surgical instrument  12010  to an open, unlatched condition. Similar to the above, the surgical instrument  12010  can include one or more indicators, such as LED  12100 , for example, configured to indicate the status of the surgical instrument  12010 . The LED  12100  can be in signal communication with the microprocessor of the surgical instrument  12010  and can operate in a similar manner to that described in connection with the LED  11100 , for example. The LED  12100  can be held in position by a bracket  12101 , for example. 
     In various instances, the instrument  12010  can include a firing lockout system which can block the advancement of the knife  12282  and/or the firing bars  12280  if the anvil  12090  is not in a closed, or a sufficiently closed, position. Referring to  FIGS.  104  and  106   , the instrument  12010  can comprise a biasing member  12400  mounted to the cartridge channel  12070 , for example, which can bias the knife  12282  into engagement with a lock portion of the handle  12015 . When the anvil  12090  is rotated into its closed position, the anvil  12090  can push the knife  12282  downwardly away from the lock portion against the biasing force of the biasing member  12400 . At such point, the knife  12282  can be advanced distally. Similarly, the instrument  12010  can include a biasing member which can bias the firing bars  12280  into engagement with a lock portion of the handle  12015  wherein the anvil  12090  can disengage the firing bars  12280  from the lock portion when the anvil  12090  is moved into its closed position. 
     The surgical instrument  12010  can comprise a manually driven closure system and a motor driven staple firing system. A portion  12040  of the handle  12015  can be gripped by one hand of the user of the surgical instrument  12010  and the anvil  12090  and the latch  12050  can be manipulated by their other hand. As part of closing the latch  12050 , in at least one embodiment, the user can move one of their hands in the general direction of their other hand which can reduce the incidental and accidental movement of the surgical instrument  12010 . The surgical instrument  12010  can be powered by any suitable power source. For instance, an electrical cable can extend from an external power source and into the handle  12015 . In certain instances, a battery can be stored in the handle  12015 , for example. 
     A surgical stapling instrument  13010  is illustrated in  FIGS.  107 - 110   .  FIG.  107    is a side view of the surgical instrument  13010  illustrated with some components removed and others shown in cross-section. The instrument  13010  can comprise a handle  13015 , a first actuator  13020 , a second actuator  13030 , a shaft assembly  13040 , and an end effector  13012  including an anvil  13050  and a staple cartridge  13055 . The shaft portion  13040  and the anvil  13050  can operate as shown and discussed in U.S. Pat. No. 5,704,534, entitled ARTICULATION ASSEMBLY FOR SURGICAL INSTRUMENTS, which issued on Jan. 6, 1998. The disclosure of U.S. Pat. No. 5,704,534, entitled ARTICULATION ASSEMBLY FOR SURGICAL INSTRUMENTS, which issued on Jan. 6, 1998, is incorporated herein by reference by its entirety. An electrical input cable  13018  can connect the instrument  13010  to an external power source. In at least one instance, the external power source can comprise a generator, such as the GEN11 generator manufactured by Ethicon Energy, Cincinnati, Ohio, for example. In various instances, the external power source can comprise an AC to DC adaptor. In certain instances, the instrument  13010  can be powered by an internal battery, such as the batteries shown and discussed in U.S. Pat. No. 8,210,411, entitled MOTOR-DRIVEN SURGICAL CUTTING INSTRUMENT, which issued on Jul. 3, 2012, for example. The disclosure of U.S. Pat. No. 8,210,411, entitled MOTOR-DRIVEN SURGICAL CUTTING INSTRUMENT, which issued on Jul. 3, 2012, is incorporated herein by reference in its entirety. 
     In various instances, referring primarily to  FIG.  107   , the anvil  13050  of the end effector  13012  can be movable between an open position, as illustrated in  FIG.  107   , and a closed position in which the anvil  13050  is positioned adjacent to, or in contact with, the staple cartridge  13055 , as described in greater detail further below. In at least one such instance, the staple cartridge  13055  may not be pivotable relative to the anvil  13050 . In certain instances, although not illustrated, the staple cartridge  13055  can be pivotable relative to the anvil  13050 . In at least one such instance, the anvil  13050  may not be pivotable relative to the staple cartridge  13055 . In any event, the user of the instrument  13010  can manipulate the end effector  13012  in order to position tissue T between the anvil  13050  and the cartridge  13055 . Once the tissue T has been suitably positioned between the anvil  13050  and the staple cartridge  13055 , the user can then pull the first actuator  13020  to actuate the closure system of the instrument  13010 . The closure system can move the anvil  13050  relative to the staple cartridge  13055 . For example, the first actuator  13020  can be pulled toward a pistol grip portion  13016  of the handle  13015  to close the anvil  13050 , as described in greater detail further below. 
     The closure drive can include a closure motor  13105  ( FIG.  110   ) configured to move the anvil  13050 . The closure motor  13105  can be mounted to the handle  13015  via a motor bracket  13101 , for example. Squeezing the first actuator  13020  from its open position ( FIG.  108   ) to its closed position ( FIG.  109   ) can energize the closure motor  13105 . Referring primarily to  FIG.  110   , the closure motor  13105  can include a rotatable output shaft which is operably engaged with a closure lead screw  13110 . When the closure motor  13105  rotates the output shaft in a first direction, the output shaft can rotate the closure lead screw  13110  in the first direction. The closure lead screw  13110  can be rotatably supported within the handle  13015  and can include a threaded portion. The closure drive can further comprise a closure nut threadably engaged with the threaded portion of the closure lead screw  13110 . The closure nut can be constrained from rotating with the closure lead screw  13110  such that the rotational motion of the closure lead screw  13110  can translate the closure nut. The closure nut can be engaged with or integrally formed with a closure yoke  13120 . When the closure motor  13015  is rotated in its first direction, the closure lead screw  13110  can advance the closure yoke  13120  distally. In various instances, the closure yoke  13120  can be slidably supported within the handle  13015  by rails  13122  extending from the handle  13015  which can constrain the movement of the closure yoke  13120  to a path defined along a longitudinal axis. Such an axis can be parallel to, substantially parallel to, collinear with, or substantially collinear with a longitudinal axis defined by the shaft assembly  13040 . The closure drive can further comprise a closure tube  13125  extending distally from the closure yoke  13120 . The closure tube  13125  can also be part of the shaft assembly  13040  and can translate relative to a frame of the shaft assembly  13040 . When the closure yoke  13120  is advanced distally by the closure lead screw  13110 , the closure yoke  13120  can advance the closure tube  13125  distally. A distal end of the closure tube  13125  can be operably engaged with the anvil  13050  such that, when the closure tube  13125  is advanced distally, the closure tube  13125  can push the anvil  13050  from its open position toward its closed position. U.S. Pat. No. 5,704,534, entitled ARTICULATION ASSEMBLY FOR SURGICAL INSTRUMENTS, which issued on Jan. 6, 1998, discloses a manually-driven closure system. 
     In at least one form, the instrument  13010  can include a closure system switch positioned in the handle  13015  which can be closed when the first actuator  13020  is moved from its open position ( FIG.  108   ) toward its closed position ( FIG.  109   ). In certain instances, the closure system switch can be closed when the first actuator  13020  is in its closed position ( FIG.  109   ). In either event, when the closure system switch is closed, a closure system power circuit can be closed to supply electrical power to the closure motor  13105  in order to rotate the closure motor  13105  in its first direction, as discussed above. In certain instances, the surgical instrument  13010  can include a microprocessor and, similar to the above, the closure system switch can be in signal communication with the microprocessor. When the closure system switch sends a signal to the microprocessor indicating that the first actuator  13020  has been closed, the microprocessor can permit power to be supplied the closure motor  13105  to operate the closure motor  13105  in its first direction and move the anvil  13050  toward its closed position. In various instances, the closure motor  13105  can move the anvil  13050  toward its closed position so long as the first actuator  13020  is at least partially actuated and the closure system switch is in a closed state. In the event that the user releases the first actuator  13020  and the first actuator  13020  is returned to its unactuated position, the closure system switch can be opened and the power supplied to the closure motor  13105  can be interrupted. Such instances may leave the anvil  13050  in a partially closed position. When the first actuator  13020  is actuated once again and the closure system switch has been closed, power can be supplied to the closure motor  13105  once again to move the anvil  13050  toward its closed position. In view of the above, the user of the surgical instrument  13010  can actuate the first actuator  13020  and wait for the closure motor  13105  to position the anvil  13050  in its fully closed position. 
     In at least one form, the movement of the first actuator  13020  can be proportional to the movement of the anvil  13050 . The first actuator  13020  can move through a first, or actuator, range of motion when it is moved between its open position ( FIG.  108   ) and its closed position ( FIG.  109   ). Similarly, the anvil  13050  can move through a second, or anvil, range of motion when it is moved between its open position ( FIG.  107   ) and its closed position. The actuator range of motion can correspond to the anvil range of motion. By way of example, the actuator range of motion can be equal to the anvil range of motion. For instance, the actuator range of motion can comprise about 30 degrees and the anvil range of motion can comprise about 30 degrees. In such instances, the anvil  13050  can be in its fully open position when the first actuator  13020  is in its fully open position, the anvil  13050  can be rotated 10 degrees toward its closed position when the first actuator  13020  is rotated 10 degrees toward its closed position, the anvil  13050  can be rotated 20 degrees toward its closed position when the first actuator  13020  is rotated 20 degrees toward its closed position, and so forth. This directly proportional movement between the first actuator  13020  and the anvil  13050  can give the user of the instrument  13010  a sense of the anvil position  13050  relative to the staple cartridge  13055  in the event that the anvil  13050  is obstructed from view in the surgical site. 
     Further to the above, the anvil  13050  can be responsive to both closing and opening motions of the first actuator  13020 . For example, when the first actuator  13020  is moved 10 degrees toward the pistol grip  13016 , the anvil  13050  can be moved 10 degrees toward the staple cartridge  13055  and, when the first actuator  13020  is moved 10 degrees away from the pistol grip  13016 , the anvil  13050  can be moved 10 degrees away from the staple cartridge  13055 . While the movement of the first actuator  13020  and the movement of the anvil  13050  can be directly proportional according to a 1:1 ratio, other ratios are possible. For instance, the movement of the first actuator  13020  and the movement of the anvil  13050  can be directly proportional according to a 2:1 ratio, for example. In such instances, the anvil  13050  will move 1 degree relative to the staple cartridge  13055  when the first actuator  13020  is moved 2 degrees relative to the pistol grip  13016 . Moreover, in such instances, the range of motion of the first actuator  13020  may be twice the range of motion of the anvil  13050 . In another instance, the movement of the first actuator  13020  and the movement of the anvil  13050  can be directly proportional according to a 1:2 ratio, for example. In such instances, the anvil  13050  will move 2 degrees relative to the staple cartridge  13055  when the first actuator  13020  is moved 1 degree relative to the pistol grip  13016 . Moreover, in such instances, the range of motion of the first actuator  13020  may be half the range of motion of the anvil  13050 . In various instances, the motion of the first actuator  13020  may be linearly proportional to the motion of the anvil  13050 . In other instances, the motion of the first actuator  13020  may be non-linearly proportional to the motion of the anvil  13050 . Regardless of the ratio that is used, such embodiments can be possible through the use of a potentiometer, for example, which can evaluate the rotation of the first actuator  13020 , as will be discussed in greater detail further below. 
     Further to the above, referring to  FIGS.  108 - 110   , the closure system of the instrument  13010  can comprise a slide potentiometer  13090  which can detect the movement of the first actuator  13020 . The first actuator  13020  can be pivotably mounted to the handle  13015  via a pivot  13021 . The first actuator  13020  can comprise a gear portion  13070  comprising a plurality of gear teeth extending circumferentially about the pivot  13021 . When the first actuator  13020  is rotated proximally toward the pistol grip  13016 , further to the above, the gear portion  13070  can be rotated distally. Correspondingly, when the first actuator  13020  is rotated distally away from the pistol grip  13016 , the gear portion  13070  can be rotated proximally. The closure system can further comprise a closure yoke rack  13080  which is slidably supported within the handle  13015 . The closure yoke rack  13080  can comprise a longitudinal array of teeth extending along a bottom surface thereof which faces the gear portion  13070  of the first actuator  13020 . The gear portion  13070  of the first actuator  13020  can be meshingly engaged with the array of teeth defined on the closure yoke rack  13080  such that, when the first actuator  13020  is rotated about the pivot  13021 , the first actuator  13020  can displace the closure yoke rack  13080  proximally or distally, depending on the direction in which the first actuator  13020  is rotated. For instance, when the first actuator  13020  is rotated toward the pistol grip  13016 , the first actuator  13020  can displace the closure yoke rack  13080  distally. Correspondingly, when the first actuator  13020  is rotated away from the pistol grip  13016 , the first actuator  13020  can displace the closure yoke rack  13080  proximally. The handle  13015  can include a guide slot defined therein which can be configured to slidably support the closure yoke rack  13080  and constrain the movement of the closure yoke rack  13080  to a path defined along a longitudinal axis. This longitudinal axis can be parallel to, substantially parallel to, collinear with, or substantially collinear with a longitudinal axis of the shaft assembly  13040 . 
     The closure yoke rack  13080  can include a detectable element  13081  mounted thereon. The detectable element  13081  can comprise a magnetic element, such as a permanent magnet, for example. The detectable element  13081  can be configured to translate within a longitudinal slot  13091  defined in the slide potentiometer  13090  when the closure rack  13080  is translated within the handle  13015 . The slide potentiometer  13090  can be configured to detect the position of the detectable element  13081  within the longitudinal slot  13091  and convey that position to the microprocessor of the surgical instrument  13010 . For example, when the first actuator  13020  is in its open, or unactuated, position ( FIG.  108   ), the detectable element  13081  can be positioned at the proximal end of the longitudinal slot  13091  and the potentiometer  13090  can transmit a signal to the microprocessor that can indicate to the microprocessor that the first actuator  13020  is in its open position. With this information, the microprocessor can maintain the anvil  13050  in its open position. As the first actuator  13020  is rotated toward the pistol grip  13016 , the detectable element  13081  can slide distally within the longitudinal slot  13091 . The potentiometer  13090  can transmit a signal, or a plurality of signals, to the microprocessor that can indicate the position of the first actuator  13020 . In response to such a signal, or a plurality of signals, the microprocessor can operate the closure motor  13105  to move the anvil  13055  to a position which corresponds to the position of the first actuator  13020 . When the first actuator  13020  is in its closed, or fully actuated, position ( FIG.  109   ), the detectable element  13081  can be positioned at the distal end of the longitudinal slot  13091  and the potentiometer  13090  can transmit a signal to the microprocessor that can indicate to the microprocessor that the first actuator  13020  is in its closed position. With this information, the microprocessor can move the anvil  13050  into its closed position. 
     When the first actuator  13020  is pulled such that it is substantially adjacent to the pistol grip  13016  of the handle  13015 , as discussed above, the closure yoke rack  13080  is moved to its most distal position. When the closure yoke rack  13080  is in its most distal position, a closure release button  13140  can engage the closure yoke rack  13080  to releasably hold the closure yoke rack  13080  in its distal most position and, as a result, releasably hold the anvil  13050  in its closed position. Referring primarily to  FIG.  108   , the closure release button  13140  can be pivotably mounted to the handle  13015  about a pivot  13141 . The closure release button  13140  can include a lock arm  13142  extending therefrom. When the first actuator  13120  is in its unactuated position and the closure yoke rack  13080  is in its proximal-most position, the lock arm  13142  may be positioned above and/or against a top surface of the closure yoke rack  13080 . In such a position, the closure yoke rack  13080  can slide relative to the lock arm  13142 . In some circumstances, the lock arm  13142  can be biased against the top surface of the closure yoke rack  13080 . As will be described in greater detail further below, the instrument  13010  can further comprise a lock  13290  configured to releasably hold the first actuator  13020  and the second actuator  13030  in the unactuated configuration depicted in  FIG.  108   . A spring  13150  can be positioned intermediate the lock  13290  and the firing button  13140  which can rotatably bias the closure release button  13140  about the pivot  13141  and position the lock arm  13142  against the top surface of the closure yoke rack  13080 . In various instances, the lock  13290  can include a proximal projection  13296  and the closure release button  13140  can include a distal projection  13146  which can be configured to hold and align the spring  13150  in position between the lock  13290  and the closure release button  13140 . When the first actuator  13020  is rotated into its actuated position, as illustrated in  FIG.  109   , the closure yoke rack  13080  can be in its distal-most position and the lock arm  13142  can be biased into, or drop into, a notch  13082  defined in the proximal end of the closure yoke rack  13080 . Moreover, when the first actuator  13020  is moved into its closed, or actuated, position illustrated in  FIGS.  109  and  110   , the first actuator  13020  can push the lock  13290  proximally and rotate the lock  13290  about pivot  13214 . In at least one instance, the first actuator  13020  can include an actuator projection  13025  extending therefrom configured to engage a distal projection  13295  extending from the lock  13290 . Such movement of the lock  13290  can compress the spring  13150  between the lock  13290  and the closure release button  13140  and increase the biasing force applied to the closure release button  13140 . Once the lock arm  13142  is engaged with the notch  13082 , the closure yoke rack  13080  may not be movable, or at least substantially movable, in the proximal direction or the distal direction. 
     As discussed above, the first actuator  13020  and the second actuator  13030  can be releasably held in and/or biased into their unactuated positions illustrated in  FIG.  108   . The instrument  13010  can include a return spring  13210  including a first end coupled to the pivot  13214  and a second end coupled to a spring mount  13034  extending from the second actuator  13030 . The second actuator  13030  can be rotatably mounted to the handle  13015  about the pivot  13021  and the return spring  13210  can apply a biasing force to the second actuator  13030  to rotate the second actuator  13030  about the pivot  13021 . The lock  13290  can stop the rotation of the second actuator  13030  about the pivot  13021 . More specifically, the spring  13150 , which acts to bias the closure return button  13140  into engagement with the closure yoke rack  13080 , can also act to push the lock  13290  distally such that a lock arm  13292  of the lock  13290  is positioned behind a shoulder  13032  defined on the second actuator  13030  which can limit the rotation of the second actuator  13030  and hold the second actuator  13030  in its unactuated position as illustrated in  FIG.  108   . Referring primarily to  FIG.  110   , the second actuator  13030  can comprise a shoulder  13031  which can be configured to abut the gear portion  13070  of the first actuator  13020  and bias the first actuator  13020  into its unactuated position ( FIG.  108   ). When the first actuator  13020  is rotated toward its actuated position ( FIG.  109   ), the first actuator  13020  can at least partially rotate the second actuator  13030  toward the pistol grip  13016  against the biasing force supplied by the spring  13210 . In fact, the actuation of the first actuator  13020  can make the second actuator  13030  accessible to the user of the surgical instrument  13010 . Prior to the actuation of the first actuator  13020 , the second actuator  13030  may be inaccessible to the user. In any event, the reader will recall that the actuation of the first actuator  13020  pushes the lock  13295  proximally. Such proximal movement of the lock  13295  can displace the lock  13295  from behind the shoulder  13032  defined on the second actuator  13030 . 
     Once the first actuator  13020  has been moved and locked into its fully actuated position ( FIG.  109   ) and the anvil  13050  has been moved into its closed position, as discussed above, the instrument  13010  can be used to staple the tissue positioned intermediate the anvil  13050  and the staple cartridge  13055 . In the event that the user is unsatisfied with the position of the tissue between the anvil  13050  and the staple cartridge  13055 , the user can unlock the anvil  13050  by depressing the closure release button  13140 . When the closure release button  13140  is depressed, the lock arm  13142  of the closure release button  13140  can be pivoted upwardly out of the notch  13082  which can permit the closure yoke rack  13080  to move proximally. Moreover, the return spring  13210  can return the first actuator  13120  and the second actuator  13130  to their unactuated positions illustrated in  FIG.  109    and, owing to the meshed engagement between the gear portion  13070  and the closure yoke rack  13080 , the return spring  13210  can return the closure yoke rack  13080  back into its proximal position. Such movement of the closure yoke rack  13080  can be detected by the slide potentiometer  13090  which can transmit a signal to the microprocessor of the instrument  13010  that the first actuator  13020  has been returned to its unactuated position and that the anvil  13050  should be returned to its open position. In response thereto, the microprocessor can instruct the closure motor  13105  to rotate in its second direction to drive the closure nut of the closing system proximally and retract the closure tube  13125  proximally which will return the anvil  13050  back to its open position. The user can then reposition the anvil  13050  and the staple cartridge  13055  and re-close the anvil  13050  by actuating the first actuator  13020  once again. In various instances, the microprocessor of the instrument  13010  can be configured to ignore input signals from the second actuator  13030  until the potentiometer  13090  detects that the anvil  13050  is in a closed, or a sufficiently closed, position. 
     Once the user is satisfied with the position of the anvil  13050  and the staple cartridge  13055 , further to the above, the user can pull the second actuator  13030  to a closed, or actuated, position such that it is in close proximity to the first actuator  13020 . The actuation of the second actuator  13030  can depress or close a firing switch  13180  in the handle  13015 . In various instances, the firing switch  13180  can be supported by a motor mount  13102  which can also be configured to support the closure motor  13105  and/or a firing motor  13100 . The closure of the firing switch  13180  can operate the firing motor  13100 . In certain instances, the firing switch  13180  can be in signal communication with the microprocessor of the surgical instrument  13010 . When the microprocessor receives a signal from the firing switch  13180  that the second actuator  13030  has been sufficiently actuated, the microprocessor can supply power to the firing motor  13100 . In various embodiments, the closure of the firing switch  13180  can connect the firing motor  13100  directly to a DC or AC power source to operate the firing motor  13100 . In at least one instance, the firing switch  13180  can be arranged such that the firing switch  13180  is not closed until the second actuator  13030  has reached its fully closed position. Referring primarily to  FIG.  110   , the rotation of the second actuator  13030  can be stopped in its fully closed position when it comes into contact with the first actuator  13020 . In at least one such instance, the first actuator  13020  can comprise a stop depression  13023  configured to receive a stop projection  13033  extending from the second actuator  13030  when the second actuator  13030  reaches its closed position. 
     The firing motor  13100  can include a rotatable output shaft which is operably engaged with a firing lead screw  13190  of the firing system. When the firing motor  13100  is operated to rotate its output shaft in a first direction, the output shaft can rotate the firing lead screw  13190  in the first direction. When the firing motor  13100  is operated to rotate its output shaft in a second, or opposite, direction, the output shaft can rotate the firing lead screw  13190  in the second direction. The firing system can further comprise a firing nut which is threadably engaged with a threaded portion of the firing lead screw  13190 . The firing nut can be constrained from rotating with the firing lead screw  13190  such that the rotation of the firing lead screw  13190  can translate the firing nut proximally or distally depending on the direction in which the firing lead screw  13190  is rotated. The firing system can further comprise a firing shaft  13220  operatively connected to the firing nut which can be displaced with the firing nut. The firing system can also comprise a knife bar  13200  and staple deploying firing bands which extend distally from the firing shaft  13220 . When the firing motor  13020  is rotated in its first direction, the firing lead screw  13190  can displace the firing nut, the firing shaft  13220 , the knife bar  13200 , and the firing bands distally to eject the staples from the staple cartridge  13055  and incise the tissue positioned intermediate the anvil  13050  and the staple cartridge  13055 . Once the knife  13200  and the firing bands reach their end of travel, the microprocessor can rotate the firing motor  13100  in its second, or opposite, direction to bring the knife  13200  and the bands back to their original position. In various instances, the instrument  13010  can include an end of travel sensor in signal communication with the microprocessor which can signal to the microprocessor that the firing drive has reached the end of its firing stroke and that the firing stroke should be retracted. Such an end of travel sensor can be positioned in the anvil  13050  and/or the staple cartridge  13055 , for example. In certain instances, an encoder operably coupled to the firing motor  13100  can determine that the firing motor  13100  has been rotated a sufficient number of rotations for the knife  13200  and firing bands to reach their end of travel and signal to the microprocessor that the firing system should be retracted. 
     Once the second actuator  13030  has been actuated, however, the instrument  13010  is in its firing state and the microprocessor can be configured to ignore any inputs from the first actuator  13020  and/or the slide potentiometer  13090  until the firing system has been returned it to its original position. In various instances, the instrument  13010  can include an abort button which, when depressed, can signal to the microprocessor that the firing assembly should be immediately retracted. In at least one such instance, the firing sequence can be halted when the closure release button  13140  is depressed. As discussed above, pressing the closure release button  13140  moves the closure yoke rack  13080  proximally which, in turn, moves the detectable element  13081  proximally. The proximal movement of the detectable element  13081  can be detected by the slide potentiometer  13090  which can signal to the microprocessor to reverse the rotation of the firing motor  13100  to retract the firing assembly and/or operate the closure motor  13105  to open the anvil  13050 . 
     The instrument  13010  can also include one or more indicators, such as LED  13300 , for example, which can be configured to indicate the operating state of the instrument  13010 . In various instances, the LED  13300  can operate in a manner similar to that of LED  11100 , for example. The instrument  13010  also incorporates the ability to articulate the end effector  13012 . This is done through the articulation knob  13240  as discussed in U.S. Pat. No. 5,704,534. Manual rotation of the shaft assembly  13040  is also discussed in U.S. Pat. No. 5,704,534. 
     In a modular concept of the instrument  13010 , the shaft assembly  13040  and the end effector  13012  could be disposable, and attached to a reusable handle  13015 . In another embodiment, the anvil  13050  and the staple cartridge  13055  are disposable and the shaft assembly  13040  and the handle  13015  are reusable. In various embodiments, the end effector  13012 , including the anvil  13015 , the shaft assembly  13040 , and the handle  13015  may be reusable and the staple cartridge  13055  may be replaceable. 
       FIG.  111    is a perspective view of a surgical stapling instrument  14010 . The instrument  14010  can comprise an actuator, or handle,  14020 , a shaft portion  14030 , a tubular cartridge casing  14040 , and an anvil  14050 . The instrument  14010  can further include a closure system configured to move the anvil  14050  between an open position and a closed position. The actuator  14020  can comprise a rotating closure knob  14075  which can operate the closure system as described in greater detail further below. The instrument  14010  can further include a firing system configured to eject staples which are removably stored in the cartridge casing  14040 . The actuator  14020  can further comprise a firing activation trigger  14070  which can operate the firing system as described in greater detail further below. Shaft portion  14030 , cartridge casing  14040 , and anvil  14050  can operate in a manner similar to that shown and discussed in U.S. Pat. No. 5,292,053, entitled SURGICAL ANASTOMOSIS STAPLING INSTRUMENT, which issued on Mar. 8, 1994. The disclosure of U.S. Pat. No. 5,292,053, entitled SURGICAL ANASTOMOSIS STAPLING INSTRUMENT, which issued on Mar. 8, 1994, is incorporated herein by reference in its entirety. 
     Further to the above, the actuator  14020  can include a transmission  14000  and a slider button  14060  configured to operate the transmission  14000 . The slider button  14060  is movable between a distal position ( FIG.  115   ), which is closer to the cartridge casing  14040 , and a proximal position ( FIG.  114   ), which is further away from the cartridge casing  14040 . When the slider button  14060  is in its proximal position, the actuator  14020  is in a first operating mode, or closure mode, and can move the anvil  14050  toward and away from the cartridge casing  14040 . When the slider button  14060  is in its distal position, the actuator  14020  is in a second operating mode, or firing mode, and can eject staples from the cartridge casing  14040  toward the anvil  14050 . When the actuator  14020  is in its closure mode, the rotating closure knob  14075  can be rotated about a longitudinal axis extending through the actuator  14020  in order to move the anvil  14050  proximally or distally depending on the direction in which the closure knob  14075  is rotated. When the actuator  14020  is in its firing mode, the firing activation trigger  14070  can be rotated proximally to eject the staples from the cartridge casing  14040 . The closure system and the firing system are discussed in greater detail further below. 
     The actuator  14020  can comprise an electric motor, such as motor  14090  ( FIGS.  113 - 115   ), for example, which can operate the closure drive and the firing drive via the transmission  14000 . The motor  14090  can be supported within an actuator housing  14080  of the actuator  14020 . Referring primarily to  FIG.  113   , the actuator housing  14080  can comprise two halves, an actuator housing right half  14080   a  and an actuator housing left half  14080   b . Actuator housing halves  14080   a  and  14080   b  can be held together by screws, although any suitable fastening and/or adhesive methods could be used to assemble actuator housing  14080 . The motor  14090  can be supported between the actuator housing halves  14080   a  and  14080   b  and can include a rotatable shaft  14100  extending distally therefrom. In certain instances, the actuator  14020  can comprise a motor support  14101  positioned in the housing  14080  configured to support the housing of the motor  14100  and constrain the motor housing from rotating relative to the actuator housing  14080 . In various instances, the rotatable shaft  14100  can comprise an extender portion  14110  affixed thereto. The shaft  14100  and the extender portion  14110  can be rotatably coupled such that they rotate together. 
     Further to the above, referring primarily to  FIG.  116   , the extender portion  14110  can comprise a cylindrical, or an at least substantially cylindrical, body  14111  and a flat portion  14120  defined in a distal end  14113  of the extender portion  14110 . The cylindrical body  14111  of the extender portion  14110  can be rotatably supported within the actuator housing  14080  by a bearing  14105 . The distal end  14113  of the extender portion  14110  can be positioned within a slider aperture  14114  defined in a slider  14115 . The slider  14115 , as will be discussed in greater detail further below, is part of the transmission  14000  and can be shifted between a proximal position ( FIG.  114   ) in which the slider  14115  transmits the rotary motion of the motor  14090  to the closure system and a distal position ( FIG.  115   ) in which the slider  14115  transmits the rotary motion of the motor  14090  to the firing system. When the slider  14115  is shifted between its proximal position ( FIG.  114   ) and its distal position ( FIG.  115   ), the slider  14115  can slide relative to the extender portion  14110 . The slider aperture  14114  defined in the slider  14115  can define a perimeter which matches, or at least substantially matches, the perimeter of the distal end  14113  of the extender portion  14110  such that, one, the extender portion  14110  and the slider  14115  are rotationally coupled together and, two, the slider  14115  can translate relative to the extender portion  14110 . In at least one instance, the slider aperture  14114  comprises a cylindrical portion  14116  which matches the cylindrical body  14111  of the extender portion  14110  and a flat portion  14117  which matches the flat portion  14120  defined in the distal end  14113  of the slider  14115 . 
     Further to the above, the slider  14115  can comprise a tubular, or a generally tubular, structure. The slider  14115  can comprise a distal end  14118  and a plurality of outer circumferential splines  14130  extending around an outer surface of the distal end  14118  which can be operably engaged with the firing drive, as illustrated in  FIG.  115   . The slider  14115  can further comprise a plurality of internal circumferential splines  14140  defined in the distal end of the slider aperture  14114  which can be operably engaged with the closure drive, as illustrated in  FIG.  114   . The slider  14115  can be part of a slider assembly  14150 . Referring primarily to  FIG.  116   , the slider assembly  14150  can further comprise an upper journal bearing  14160 , a lower journal bearing  14170 , the slider button  14060 , and a slider spring  14180 . The upper journal bearing  14160  and the lower journal bearing  14170  combine to form a journal bearing which can, one, support the slider  14115  loosely enough so that the slider  14115  may rotate within the journal bearing and, two, displace the slider  14115  proximally and distally. Referring primarily to  FIG.  116   , the slider  14115  can comprise a distal flange  14121  and a proximal flange  14122  extending therefrom which can define a recess  14123  therebetween which is configured to closely receive the journal bearing. When the slider button  14060  is pushed distally, the journal bearing can bear against the distal flange  14121  to push the slider  14115  distally. Correspondingly, when the slider button  14060  is pushed proximally, the journal bearing can bear against the proximal flange  14122  to push the slider  14115  proximally. 
     The slider assembly  14150  can comprise a lock configured to releasably hold the slider  14115  in position. Referring primarily to  FIG.  116   , the slider button  14060  can comprise a flange  14181  that can selectively fit into a first depression defined at a first, or proximal, end of a longitudinal slot defined in the actuator housing  14080  and a second depression defined at a second, or distal, end of the longitudinal slot. When the flange  14181  is engaged with the proximal depression, the flange  14181  can hold the slider assembly  14150  in its proximal position which operably engages the slider  14115  and the closure drive with the motor  14090 . When the flange  14181  is engaged with the distal depression, the flange  14181  can hold the slider assembly  14150  in its distal position which operably engages the slider  14115  and the firing drive with the motor  14090 . The upper journal bearing  14160  can include a journal aperture  14161  configured to slidably receive a shaft  14061  of the button  14060 . The button  14060  can be pushed downwardly within the journal aperture  14161  to disengage the flange  14181  from the actuator housing  14080 . Once the flange  14181  has been disengaged from the actuator housing  14080 , the button  14060  can be slid within the longitudinal slot defined in the actuator housing  14080  to move the slider  14115  between its proximal and distal positions. The spring  14180  can be configured to bias the flange  14181  toward the actuator housing  14080  and, when the user of the surgical instrument  14010  releases the button  14060 , the spring  14180  can bias the button  14060  upwardly into engagement with the actuator housing  14080  once again. 
     When the slider assembly  14150  is in its proximal position, further to the above, the slider  14115  is engaged with a closing nut  14190  of the closure drive. The closing nut  14190  comprises an elongate tubular structure including closing nut external splines  14200  defined at the proximal end thereof. When the slider  14115  is in its proximal position, the internal splines  14140  of the slider  14115  are meshingly engaged with the external splines  14200  of the closing nut  14190  such that, when the slider  14115  is rotated by the motor  14090 , the closing nut  14190  is rotated by the slider  14115 . The closing nut  14190  can be rotatably supported within the actuator housing  14080  by one or more bearings, such as bushing  14220 , for example, which rotatably supports the distal end of the closing nut  14190 . The closing nut bushing  14220  may be comprised of Delrin, Nylon, copper, brass, bronze, and/or carbon, for example. In certain instances, the closing nut bushing  14220  can comprise a ball bearing or roller bearing, for example. In various instances, the closing nut bushing  14220  may be an integral portion of the actuator housing  14080 . 
     The closing nut  14190  can comprise a longitudinal aperture  14191  defined therein. The closure system can further comprise a closing rod  14230  which can be at least partially positioned within the longitudinal aperture  14191 . The closing rod  14230  can comprise a thread  14231  defined thereon which is threadably engaged with a closing nut thread  14210  defined in the longitudinal aperture  14191 . The closing rod  14230  can be constrained from rotating with the closing nut  14190  such that, when the closing nut  14190  is rotated in a first direction by the motor  14090 , the closing rod  14230  can be translated proximally by the closing nut  14190 . As illustrated in  FIG.  115   , the closing rod  14230  can move proximally within the longitudinal aperture  14191  of the closing nut  14190 . Similarly, when the closing nut  14190  is rotated in an opposite, or second, direction by the motor  14090 , the closing rod  14230  can be translated distally by the closing nut  14190 . As will be described in greater detail further below, the closing rod  14230  can be operably engaged with the anvil  14050  such that, when the closing rod  14230  is pulled proximally, the anvil  14050  can be moved toward the cartridge casing  14040 . Correspondingly, when the closing rod  14230  is pushed distally, the anvil  14050  can be moved away from the cartridge casing  14040 . In various instances, a closure stroke length of the closure system can be measured between the open position and the closed position of the anvil  14050 . The closing rod  14230  can be at least as long as the closure stroke length to accommodate the same. 
     As discussed above, the button  14060  of the actuator  14020  is movable between a proximal position ( FIG.  114   ) in which the transmission  14000  is engaged with the closure drive and a distal position ( FIG.  115   ) in which the transmission  14000  is engaged with the firing drive. In this way, the transmission  14000  can be used to selectively couple the closure drive and the firing drive with the motor  14090 . When the user of the surgical instrument  14010  is satisfied with the position of the anvil  14050  relative to the cartridge casing  14040 , the user can displace the button  14060  distally, as illustrated in  FIG.  115   , to disengage the slider  14115  from the closing drive and engage the slider  14115  with the firing drive. When the slider  14115  is slid distally, the internal splines  14140  of the slider  14115  are disengaged from the external splines  14200  of the closing nut  14190  such that the subsequent rotation of the slider  14115  is no longer transmitted to the closing nut  14190  and the closure system. Concurrent with the disengagement of the slider from the closure system, the slider  14115  can become engaged with the firing system. Alternatively, the slider  14115  can become disengaged from the closure system as the slider  14115  is displaced distally and, owing to additional distal displacement of the slider  14115 , the slider  14115  can become engaged with the firing system. In such circumstances, the transmission  14000  may not operably engage the closure drive and the firing drive with the motor  14090  at the same time. In any event, the firing system can include a firing nut  14260  which can be engaged by the slider  14115  when the slider  14115  is moved distally. 
     Further to the above, referring primarily to  FIG.  116   , the firing nut  14260  can include an aperture  14261  defined therein which can be configured to receive the distal end  14118  of the slider  14115  therein when the slider  14115  is advanced into its distal position ( FIG.  115   ). The firing nut aperture  14261  can include firing nut splines  14270  defined around an inner circumference thereof which can intermesh with the outer circumferential splines  14130  of the slider  14115 . When the outer circumferential splines  14130  of the slider  14115  are engaged with the firing nut splines  14270  of the firing nut  14260 , the slider  14115  can be rotatably coupled with the firing nut  14260  such that the rotation of the slider  14115  is transmitted to the firing nut  14260 . The actuator  14020  can further comprise a firing nut bushing  14275  that rotatably supports the firing nut  14260 . The firing nut bushing  14275  may comprise a needle bearing, a Delrin, Nylon, and/or other plastic bushing, a metal bushing, or an integral part of the actuator housing  14080 , for example. The firing nut  14260  can further comprise internal threads  14272  defined in a distal interior surface of the firing nut aperture  14261 . The firing system can further comprise a firing tube  14280  threadably engaged with the internal threads  14272  of the firing nut  14260 . 
     In various instances, further to the above, the firing tube  14280  can include a thread  14281  defined on an outer surface thereof which is threadably engaged with the internal threads  14272 . The firing tube  14280  can be constrained from rotating with the firing nut  14260  such that, when the firing nut  14260  is rotated by the motor  14090  and the slider  14115 , the firing nut  14260  can translate the firing tube  14280 . For instance, when the firing nut  14260  is rotated in a first direction, the firing tube  14280  can be displaced distally by the firing nut  14260  and, when the firing nut  14260  is rotated in a second, or opposite, direction, the firing tube  14280  can be displaced proximally by the firing nut  14260 . At least a portion of the firing tube  14280  can be positioned within the aperture  14261  defined in the firing nut  14260 . When the firing tube  14280  is displaced proximally, the firing tube  14280  can move proximally within the aperture  14261 . When the firing tube  14280  is displaced distally, the firing tube  14280  can move distally within the aperture  14261 . As will be described in greater detail below, the firing tube  14280  can be operably connected with a firing member which can eject the staples from the cartridge housing  14040  when the firing tube  14280  is advanced distally. The firing tube  14280  can retract the firing member when the firing tube  14280  is moved proximally. The firing tube  14280  can be long enough to accommodate the firing stroke of the firing member when the firing member is moved between an unfired position and a fired position. In various instances, the threaded portion of the firing tube  14280  is shorter than the threaded portion of the closure rod  14230 . In such circumstances, the firing stroke can be shorter than the closure stroke. In other instances, the threaded portion of the firing tube  14280  can be the same length as the threaded portion of the closure rod  14230 . In such instances, the firing stroke can be the same length as the closure stroke. In certain instances, the threaded portion of the firing tube  14280  is longer than the threaded portion of the closure rod  14230 . In such circumstances, the firing stroke can be longer than the closure stroke. 
     Further to the above, the actuator  14020  and the shaft portion  14030  can comprise an integral system. In various instances, the actuator  14020  and the shaft portion  14030  can comprise a unitary assembly. In certain instances, the actuator  14020  can be disassembled from the shaft portion  14030 .  FIG.  34    is a perspective view of the surgical stapling instrument  14010  depicting the actuator  14020  disassembled from the shaft portion  14030 . The instrument  14010  can comprise one or more locks or latches configured to releasably hold the shaft portion  14030  to the actuator  14020 . For instance, the actuator  14020  can include latches  14025  on opposite sides thereof which are configured to releasably hold the shaft portion  14030  to the actuator  14020 . The latches  14025  can be slid between a first position in which they are engaged with the shaft portion  14030  and a second position in which they have been disengaged from the shaft portion  14030 . As described in greater detail below, the actuator  14020  and the shaft portion  14030  can comprise portions of the closure system which are operably assembled together when the shaft portion  14030  is assembled to the actuator  14020 . Similarly, the actuator  14020  and the shaft portion  14030  can comprise portions of the firing system which are operably assembled together when the shaft portion  14030  is assembled to the actuator  14020 . 
     Further to the above, referring primarily to  FIG.  113   , the closure system can further comprise a closing fixture piece  14240  affixed to the distal end of the closing rod  14230 . In various instances, a screw can lock the closing fixture piece  14240  to the closing rod  14230  such that the closing fixture piece  14240  is translated distally when the closing rod  14230  is translated distally and, correspondingly, translated proximally when the closing rod  14230  is translated proximally. The closing fixture piece  14240  can comprise one or more lateral extensions that can fit into grooves in the actuator housing  14080  to align the closing fixture piece  14240  and the closing rod  14230 . The lateral extensions can also prevent the closing rod  14230  and the closing fixture piece  14240  from rotating when the closing rod  14230  is driven by the closing nut  14190 , as discussed above. The closing fixture piece  14240  may comprise a closing drive output of the actuator  14020  and can be attached to a closure drive input of the shaft portion  14030 . The closure drive input of the shaft portion  14030  can comprise a second fixture piece  14250  which can be attached to the closing fixture piece  14240  when the shaft portion  14030  is assembled to the actuator  14020 . The closing fixture piece  14240  can push the second fixture piece  14250  distally when the closing fixture piece  14240  is advanced distally by the closing rod  14230 ; correspondingly, the closing fixture piece  14240  can pull the second fixture piece  14250  proximally when the closing fixture piece  14240  is retracted proximally by the closing rod  14230 . 
     The closing drive portion of the shaft portion  14030  can further comprise one or more tension bands  14252  and  14253  mounted to and extending from the second fixture piece  14250 . The tension bands  14252  and  14253  can be fastened to the second fixture piece  14250  such that the second fixture piece  14250  can push the tension bands  14252 ,  14253  distally when the second fixture piece  14250  is advanced distally by the closing fixture piece  14240  and, correspondingly, such that the second fixture piece  14250  can pull the tension bands  14252 ,  14253  proximally when the second fixture piece  14250  is retracted proximally by the closing fixture piece  14240 . In various instances, the shaft portion  14030  can be curved and, in at least one instance, can include a curved shaft housing  14031  extending from a proximal housing mount  14032 . In certain instances, the tension bands  14252  and  14253  can be flexible to accommodate a curved path of the closing drive portion of the shaft portion  14030 . The closing drive portion of the shaft portion  14030  can further comprise an attachment portion, or trocar,  14258  attached to the tension bands  14253  and  14253 . The trocar  14258  can be fastened to the tension bands  14252 ,  14253  such that the trocar  14258  is advanced and retracted with the tension bands  14252 ,  14253 . The trocar  14258  can comprise a distal end which can be releasably engaged with the anvil  14050  such that the anvil  14050  is advanced and retracted with the trocar  14258  when the anvil  14050  is assembled to the trocar  14258 . U.S. Pat. No. 5,292,053, referenced above, discusses this in greater detail. 
     Further to the above, referring primarily to  FIG.  113   , the firing system can further comprise a firing fixture piece  14290  affixed to a distal end of the firing tube  14280 . In various instances, a screw can lock the firing fixture piece  14290  to the firing tube  14280  such that the firing fixture piece  14290  is translated distally when the firing tube  14280  is translated distally and, correspondingly, translated proximally when the firing tube  14280  is translated proximally. The firing fixture piece  14290  can comprise one or more lateral extensions that can fit into grooves in the actuator housing  14080  to align the firing fixture piece  14290  and the firing tube  14280 . The lateral extensions can also prevent the firing tube  14280  and the firing fixture piece  14290  from rotating when the firing tube  14280  is driven by the firing nut  14260 , as discussed above. The firing fixture piece  14290  may comprise a firing drive output of the actuator  14020  and can be attached to a firing drive input of the shaft portion  14030 . The firing drive input of the shaft portion  14030  can comprise a second fixture piece  14300  which can be attached to the firing fixture piece  14290  when the shaft portion  14030  is assembled to the actuator  14020 . The firing fixture piece  14290  can mate in a tongue-in-groove manner with the secondary firing fixture piece  14300 . When assembled, the firing fixture piece  14290  can push the second fixture piece  14300  distally when the firing fixture piece  14290  is advanced distally by the firing tube  14280 ; correspondingly, the firing fixture piece  14290  can pull the second fixture piece  14300  proximally when the firing fixture piece  14290  is retracted proximally by the firing tube  14280 . 
     The firing drive can further comprise a staple driver  14310  coupled to the second fixture piece  14300  such that the staple driver  14310  moves proximally and distally with the second fixture piece  14300 . When the staple driver  14310  is moved distally by the second fixture piece  14300 , the staple driver  14310  can eject the staples from the cartridge housing  14040 . In various instances, the second fixture piece  14300  can advance a knife  14320  distally with the staple driver  14310  to incise tissue captured between the anvil  14050  and the cartridge housing  14040 . The second fixture piece  14300  can retract the staple driver  14310  and the knife  14320  proximally when the second fixture piece  14300  is retracted proximally by the firing fixture piece  14290 . 
     Further to the above, it can be noted that portions of the closing system comprising the closing nut  14190  and the closing rod  14230  and portions of the firing system comprising the firing nut  14260  and the firing tube  14280  can be concentric and nested. The firing nut  14260  and the firing tube  14280  may be considered an outer mechanism while the closing nut  14190  and the closing rod  14230  may be considered an inner mechanism. Together with the slider  14115 , the closing nut  14190 , the closing rod  14230 , the firing nut  14260 , and the firing tube  14280  can comprise the transmission  14000 . The concentric and nested arrangement of the transmission  14000  can reduce the space required by the closing and firing systems in order to create a smaller and more easily held actuator  14020 . This arrangement also allows the outer mechanism to serve as support and provide bearing surfaces for moving parts of the inner mechanism. In the embodiment shown, the translation members of the inner mechanism are shown longer than the translation members of the outer mechanism. The closing rod  14230  may be, for example, of the order of two inches while the firing tube  14280  is of the order of one inch, for example; however, any suitable lengths can be used. Longer translation members are useful when longer translation distances are needed. In the embodiment shown, the inner mechanism, or closure drive, can drive a load a longer distance than the outer mechanism, or firing drive. That said, the firing drive could drive a load a longer distance than the firing drive. 
     As discussed above, the actuator  14020  and the shaft portion  14030  are designed for easy assembly. The firing fixture piece  14290  comprises a semi-circular lip at the end of a distally extending flange. This semi-circular lip fits into a semi-circular groove at a proximal end of the second firing fixture piece  14300 . Because the fit is about a semicircular surface, it is possible to connect firing fixture piece  14290  with the second firing fixture piece  14300  by translating the firing fixture piece  14290  toward the second firing fixture piece  14300  in a direction transverse or orthogonal to a general longitudinal axis of the pieces. Connection of the closure assembly pieces is also facilitated generally in the same manner. For instance, the closing fixture piece  14240  can comprise a distally extending flange. At a distal end of this flange is a semi-circular lip extending from a substantially semi-cylindrical portion of the closing fixture piece  14240 . A circumferential groove on a proximal portion of the second fixture piece  14250  receives this semi-circular lip to attach the closing fixture piece  14240  to the second fixture piece  14250 . Because of the semi-circular nature of closing fixture piece  14240 , the closing fixture piece  14240  and the second fixture piece  14250  may be assembled and disassembled by translation transverse or orthogonal to the general longitudinal axis of the pieces, thus facilitating quick connection and disconnection of the shaft portion  14030  and the actuator  14020 . 
     Referring generally to  FIG.  113   , the firing trigger  14070  and the closing knob  14075  are further displayed in exploded view to better see their interaction with adjacent parts. The closing knob  14075  is rotatable in a first, or clockwise, direction and a second, or counterclockwise, direction. When the closing knob  14075  is rotated in the first direction, the closing knob  14075  can contact and close a first switch and, when the closing knob  14075  is rotated in the second direction, the closing knob  14075  can contact and close a second switch. When the first switch is closed by the closing knob  14075 , the motor  14090  can be energized and operated in a first direction and, when the second switch is closed by the closing knob, the motor  14090  can be energized and operated in a second direction. When the motor  14090  is operated in its first direction, the motor  14090  can drive the closing rod  14230  distally to move the anvil  14050  away from the cartridge casing  14040  and, when the motor  14090  is operated in its second direction, the motor  14090  can drive the closing rod  14230  proximally to move the anvil  14050  toward the cartridge casing  14040 . The closing knob  14075  can be positionable in a center, or neutral, position in which neither the first switch nor the second switch are closed and the motor  14090  is not responsive to the closing knob  14075 . In various instances, the instrument  14010  can comprise at least one spring, such as spring  14076 , for example, configured to bias the closing knob  14075  into its neutral position, for example. 
     Turning now to the firing trigger  14070 , the firing trigger  14070  is rotatably pinned to the actuator housing  14080  and is spring-loaded by a torsion spring  14071  that forces the firing trigger  14070  to a position which is rotated away from the actuator housing  14080 . A firing switch  14305  located near the firing trigger  14070  is in a position to be contacted by the firing trigger  14070  when the firing trigger  14070  is rotated toward the actuator housing  14080  against the biasing force of the torsion spring  14071 . The firing trigger  14070  can close the firing switch  14305  when the firing trigger  14070  is actuated. When the firing switch  14305  is closed, the motor  14090  can be operated in a first direction to advance the firing tube  14280  and the staple driver  14310  distally. When the firing trigger  14070  is released, the torsion spring  14071  can move the firing trigger  14070  back to its unactuated position and out of contact with the firing switch  14305 . At such point, the firing switch  14305  may be in an open condition and the motor  14090  may not be responsive to the firing trigger  14070 . In various instances, the instrument  14010  can further comprise a safety latch  14320  rotatably pinned to the actuator housing  14080  which is rotatable between a locked position which blocks the firing trigger  14070  from being actuated and a second position in which the firing trigger  14070  can be actuated to close the firing switch  14035 . In any event, the motor  14090  can be operated in a second direction to retract the firing tube  14280  and the staple driver  14310 . In certain instances, the motor  14090  can be switched between the first direction and the second direction when the firing system has reached the end of its firing stroke. In some instances, the actuator  14020  can further comprise a reversing button and switch which can be operated to operate the motor  14090  in its second direction. 
     In view of the above, a method of using the instrument  14010  is provided below, although any suitable method could be used. Moreover, it has been described above that the actuator  14020  is capable of providing two outputs and the shaft portion  14030  is capable of receiving two inputs to perform two functions. Such functions have been described as closing functions and firing functions, but the invention is not so limited. The functions could include any suitable functions, such as an articulation function, for example. To use the actuator  14020 , in various instances, a user can first assemble the actuator  14020  to the shaft portion  14030  by moving the actuator  14020  toward the shaft portion  14030  perpendicular to the longitudinal axis of the actuator  14020 , as seen in  FIG.  112   . The user can align the open side of the proximal end of the shaft portion  14030  toward the open side of the distal portion of the actuator  14020  and assemble the pieces together. Such assembly can connect the closing and firing fixture pieces as discussed above. As also discussed above, the latches  14025  on the actuator  14020  can grip ledges on the shaft portion housing  14032  to releasably hold the actuator  14020  and the shaft portion  14030  together. After assembling the actuator  14020  and the shaft portion  14030 , a user can place the slider assembly  14150  in its first position to use the first desired function of the surgical tool of the attached portion. As discussed above, the button  14060  can be utilized to position the slider assembly  14150  in its first portion. 
     Referring generally to  FIG.  114   , the inner splines  14140  on the slider  14115  can engage the external splines  14200  on the closing nut  14190  when the slider assembly  14150  is in its first position. The user would then rotate closing knob  14075  to position the anvil  14050  relative to the cartridge housing  14040 . As discussed above, the closing knob  14075  can be rotated in its first direction to close the first closure switch and move the anvil  14050  away from the cartridge housing  14040  and its second direction to close the second closure switch and move the anvil  14050  toward the cartridge housing  14040 . In certain instances, the closure of the first closure switch can close a circuit which operates the motor  14090  in its first direction and, correspondingly, the closure of the second closure switch can close a circuit which operates the motor  14090  in its second direction. In certain instances, the first closure switch and the second closure switch can be in communication with a microprocessor of the surgical instrument  14010  which can control the electrical power supplied, including the polarity of the electrical power supplied, to the motor  14090  based on the input from the first closure switch and the second closure switch. As discussed above, the motor  14090  can rotate the rotatable shaft  14100 , the extender portion  14110 , the slider  14115 , and owing to the configuration of the transmission  14000 , the closing nut  14190 . As discussed above, the closing nut  14190  is threadably engaged with the closing rod  14230  which displaces the anvil  14050  proximally and distally. Alternatively, the closing rod  14230  could perform some other function. 
     When the slider assembly  14150  is in its first, or proximal, position, as illustrated in  FIG.  114   , the motor  14090  may be responsive to the closing knob  14075  and not the firing trigger  14070 . In at least one instance, the lower journal bearing  14170  of the slider assembly  14150  can contact and close a first transmission switch  14340  when the slider assembly  14150  is in its first position. In various instances, the first transmission switch  14340  can be in communication with the microprocessor of the surgical instrument  14010  which can be configured to ignore input from the firing switch  14305  when the first transmission switch  14340  has been closed. In such circumstances, the user of the surgical instrument  14010  may depress the firing trigger  14070  and the motor  14090  will not be responsive thereto. Rather, in such circumstances, the motor  14090  is responsive to the first and second closure switches which are actuated by the closing knob  14075  to move the anvil  14050 . When the slider assembly  14150  is moved toward its second, or distal, position, as illustrated in  FIG.  115   , the lower journal bearing  14170  is disengaged from the first transmission switch  14340  and the first transmission switch  14340  will return to an open condition. When the slider assembly  14150  is moved into its second, or distal, position, the lower journal bearing  14170  can contact and close a second transmission switch  14350 . In various instances, the second transmission switch  14350  can be in communication with the microprocessor of the surgical instrument  14010  which can be configured to ignore input from the closure knob  14075  when the second transmission switch  14350  has been closed. In such circumstances, the user of the surgical instrument  14010  may rotate the closing knob  14075  and the motor  14090  will not be responsive thereto. Rather, in such circumstances, the motor  14090  is responsive to the firing switch  14305  which is actuated by the firing trigger  14070 . 
     In order to move the slider assembly  14150  from its first position to its second position, as discussed above, the user can depress the slider button  14060  to release the slider button  14060  from its detent and move the slider assembly  14150  distally to its second position. In such circumstances, the slider  14115  can be disengaged from the closing nut  14160  and engaged with the firing nut  14260 . More particularly, the inner splines  14140  on the slider  14115  can become disengaged from the external splines  14200  on the closing nut  14190  and, furthermore, the outer splines  14130  of the slider  14150  can become engaged with the inner splines  14270  of the firing nut  14260 . At such point, the user can rotate the safety latch  14320  to its unlocked position to ready the firing trigger  14070  for firing. The user can fire the firing system by rotating the firing trigger  14070  counterclockwise as depicted in  FIG.  115    toward actuator housing  14080 . As discussed above, the firing trigger  14070  can contact a firing switch  14305  which can electrically energize the motor  14090 . Similar to the first configuration of the transmission  14000 , the motor  14090  can rotate the rotatable shaft  14100 , the extender portion  14110 , and the slider  14115 ; however, in the second configuration of the transmission  14000 , the slider  14115  rotates the firing nut  14260  to translate the firing tube  14280 . 
     In various instances, power can be supplied to the instrument  14010  by an external power source. In certain instances, one or more batteries positioned within the actuator  14020  could be utilized. The batteries could be, for example, lithium rechargeable batteries. In some instances, the batteries and the motor  14090  could be positioned in a sealed, removable housing that is cleanable, sterilizable, and reusable. 
     After the actuator  14020  has been used during a surgical procedure, the user may disassemble the actuator  14020  from the shaft portion  14030 . The user may depress the latches  14025  to disassemble the actuator  14020  from the shaft portion  14030 . Thereafter, the actuator  14020  can be cleaned, sterilized, and reused or disposed of. Similarly, the shaft portion  14030  can be cleaned, sterilized, and reused or disposed of. When the shaft portion  14030  is reused, staples can be reloaded into the cartridge housing  14040 . In certain instances, the cartridge housing  14040  can include a replaceable cartridge which can be used to reload the staples. In various instances, various portions of the actuator  14020  may also be combined in a sealed, compartmentalized module which can be easily inserted into and removed from the actuator housing  14080 . For example, the motor  14090 , the rotatable shaft  14100 , the extender portion  14110 , the slider assembly  14150 , the closing nut  14190 , the closing rod  14230 , the firing nut  14260 , and the firing tube  14280  may be combined into a modular assembly removable from the actuator housing  14080 . Furthermore, portions of the actuator  14020  may be part of separate assemblable modules. For example, electronic portions of the actuator  14020 , such as the motor  14090  and a battery, may comprise one module, while mechanical assemblies containing rotating and/or translating parts may comprise a second module. In such circumstances, the first module may be sterilized by different methods than the second module. Such circumstances can facilitate the use of, for example, gamma radiation for the second module which may be inappropriate for sterilizing the first module. 
     Various additions to the actuator  14020  are envisioned. For example, microprocessing may be utilized to detect the end-of-stroke positions of the closing system and/or the firing system and to signal the motor  14090  when to stop the closing stroke and/or the firing stroke. Microprocessing could also be utilized to determine the type of shaft assembly that is attached to the actuator  14020 . For instance, the actuator  14020  can include a sensor in signal communication with the microprocessor in the actuator  14020  that a circular stapler shaft assembly is attached the actuator  14020  or that a linear cutter shaft assembly is attached to the actuator  14020 . It is envisioned that the actuator  14020  can power many types of surgical tools requiring at least one and perhaps two or more longitudinal motion inputs, for example. In various instances, the actuator  14020  can power a circular stapler, a liner stapler, a right-angle stapler, scissors, graspers, and/or other types of surgical instruments, for example. 
     Further modifications of the actuator  14020  include utilizing multiple motors so that the number of functions employable by the actuator  14020  can be increased. Certain modifications of the actuator  14020  include performing more than two functions with the same motor. For example, a third position of the slider assembly  14150  is envisioned wherein a third function is driven by a third nested mechanism. In some instances, further to the above, the slider assembly  14150  may have a third position which is an idler or neutral position wherein no function is driven by the motor  14090 . Further modifications may include the use of electrical and/or magnetic means to translate the slider  14115  from one position to another. For example, a solenoid may be used to move the slider  14115  from one position to another. A spring may preload the slider  14115  into a default position, and energizing the solenoid may move the slider  14115  from the default position to a second position. 
     A surgical stapling instrument  15010  is illustrated in  FIGS.  117  and  118   . Similar to the above, the instrument  15010  can comprise a handle, a closure system configured to move an anvil  15090  between an open position ( FIG.  117   ) and a closed position ( FIG.  118   ) relative to a staple cartridge  15080  and, in addition, a firing system configured to deploy staples from the staple cartridge  15080  and incise tissue captured between the anvil  15090  and the staple cartridge  15080 . The housing of the surgical instrument handle has been removed from  FIGS.  117  and  118    for the purposes of illustrating various components contained therein. Also similar to the above, the closure system of the instrument  15010  can comprise a closing motor  15110 , a closing gear train including closure drive screw gear  15160  operably coupled to the closing motor  15110 , and a closure drive screw  15170  operably coupled to the closure drive screw gear  15160 . In various instances, the closing motor  15110  can be supported by a motor frame  15125  which can, in addition, rotatably support the closure drive screw gear  15160  and the closure drive lead screw  15170 . The closure system can further include a closure button  15065  configured to contact and close a closure switch  15285  which, when closed, can operate the closing motor  15110 . In some instances, further to the above, the closure button  15065  can be configured to contact a closure switch configured to operate the closure motor  15110  in a first direction and close the anvil  15090  and an opening switch configured to operate the closure motor  15110  in a second direction and open the anvil  15090 . 
     Further to the above, the closure system can further comprise a carriage  15180  configured to engage the anvil  15090  and move the anvil  15090  between its open position (FIG.  117 ) and its closed position ( FIG.  118   ). The carriage  15180  can include a threaded nut portion  15175  which is threadably engaged with a threaded portion of the closure drive lead screw  15170 . The carriage  15180  can be constrained from rotating with the closure drive lead screw  15170  such that the rotation of the closure drive lead screw  15170  can translate the carriage  15180  proximally and distally, depending on the direction in which the closure drive lead screw  15170  is rotated. When the closure drive lead screw  15170  is rotated in a first direction by the closing motor  15110 , the closure drive lead screw  15170  can displace the carriage  15180  distally to close the anvil  15090 . Correspondingly, when the closure drive lead screw  15170  is rotated in a second, or opposite, direction, by the closing motor  15110 , the closure drive lead screw  15170  can displace the carriage  15180  proximally to open the anvil  15090 . The carriage  15180  can be at least partially disposed around a cartridge channel  15070  and, in various instances, can be slidably retained to the cartridge channel  15070 . Referring primarily to  FIG.  118   , the cartridge channel  15070  can include one or more slots  15195  defined in opposite sides thereof which are configured to slidably receive one or more projections  15185  extending inwardly from the carriage  15080 . In other circumstances, the channel  15070  can comprise the projections  15185  and the carriage  15080  can comprise the slots  15195 . In either event, the slots  15195  and the projections  15185  can be configured to constrain the movement of the carriage  15180  to a longitudinal, or substantially longitudinal, path, for example. 
     The carriage  15080  is movable from a first, or proximal, position ( FIG.  117   ) to a second, or distal, position ( FIG.  118   ) to close the anvil  15090 . The carriage  15080  can include a crossbar  15081  which is configured to contact and move the anvil  15090  when the carriage  15080  is moved relative to the anvil  15090 . In various instances, the anvil  15090  can be pivotably coupled to the cartridge channel  15070  about a pivot  15200  and the anvil  15090  can be rotated about the pivot  15200  by the carriage crossbar  15081 . More specifically, the carriage crossbar  15181  can be configured to contact a top, or cam, surface  15092  of the anvil  15090  and slide across the top surface  15092  as the carriage  15080  is moved distally to rotate the anvil  15090  toward the cartridge  15080  positioned in the cartridge channel  15070 . In some instances, the distal end  15091  of the anvil  15090  can contact the distal end  15081  of the cartridge  15080  when the anvil  15090  reaches its fully closed position. The carriage  15180  can be advanced distally until it reaches its distal-most position and/or the anvil  15090  is in its fully closed position, which is illustrated in  FIG.  118   . In various circumstances, the carriage  15180  can contact and close an end-of-stroke sensor when the carriage  15180  reaches its distal-most position. In certain instances, the end-of-stroke sensor can be in signal communication with a microprocessor of the surgical instrument  15010 . When the end-of-stroke sensor is closed by the carriage  15180 , the microprocessor can interrupt the power supplied to the closing motor  15110  and stop the advancement of the carriage  15180 . 
     As discussed above, the crossbar  15181  of the carriage  15180  can cam the anvil  15090  toward the staple cartridge  15080  by pushing the cam surface  15092  downwardly. The anvil  15090  can further comprise a latch pin  15210  extending from the sides thereof which can be received in slots  15215  defined in the sides of the cartridge channel  15070  when the anvil  15090  is rotated toward the staple cartridge  15080 . In various instances, the latch pin  15210  can contact the closed ends of the slots  15215  when the anvil  15090  reaches its closed position, for example. In some instances, the anvil  15090  may be in a closed position and the latch pin  15210  may not be in contact with the closed ends of the slots  15215 . In certain instances, the closure system can comprise one or more latches  15190  configured to engage the latch pin  15210  and/or move the anvil  15090  closer to the staple cartridge  15080 . The latches  15190  can be rotatably coupled to the cartridge channel  15070  by a pivot pin  15191  and can be rotated about a pivot axis to engage the latch pin  15210 . In some instances, the latches  15190  can engage the latch pin  15210  and position the latch pin  15210  against the closed ends of the slots  15215 . Each latch  15190  can comprise a latch arm  15192  which can slide over the latch pin  15210  and push the latch pin  15210  downwardly as the latch  15190  is rotated distally into its closed position. Each latch arm  15192  can at least partially define a latch slot  15193  which can be configured to receive the latch pin  15210  as the latches  15190  are moved into their actuated positions. The latch arms  15192  and the closed ends of the slots  15215  can co-operate to trap and/or hold the latch pin  15210  in position. 
     Further to the above, the latches  15190  can be moved between an unlatched position ( FIG.  117   ) and a latched position ( FIG.  118   ) by the carriage  15180  when the carriage  15180  is advanced distally. To the extent that the anvil  15090  is not moved into its fully closed position by the crossbar  15181 , the latches  15190  can move the anvil  15090  into its fully closed position. In various instances, the carriage  15180  can include distal cam surfaces  15182  defined thereon which can engage the latches  15190  when the carriage  15180  is advanced distally. In at least one such instance, each cam surface  15182  can comprise a sloped or angled surface, for example. When the closure drive lead screw  15170  is rotated in its second direction and the carriage  15180  is retracted proximally by the closure drive lead screw  15170 , the latches  15190  can be returned to their unactuated positions. In various instances, the instrument  15010  can further comprise one or more biasing springs  15195 , for example, which can be configured to rotate the latches  15190  proximally when the distal cam surfaces  15182  are retracted away from the latches  15190 . Each latch  15190  can include an aperture  15194  defined therein configured to receive a first end of a spring  15195 . A second end of each spring  15195  can be engaged with a spring post  15079  extending from the cartridge channel  15070 . When the latches  15190  are rotated distally from their unlatched positions to the their latched positions by the carriage  15180 , as discussed above, the springs  15195  can be resiliently stretched such that, when the carriage  15180  is retracted, the springs  15195  can elastically return to their original condition thereby applying a force to the latches  15090  via the apertures  15194 , for example. In any event, when the latches  15190  have been returned to their unlatched positions, the anvil  15090  can be moved relative to the staple cartridge  15080  once again. 
     As discussed above, the crossbar  15181  of the carriage  15180  can contact the cam surface  15092  of the anvil  15090  to rotate the anvil  15090  toward the staple cartridge  15080 . The carriage  15180  can also be configured to rotate the anvil  15090  away from the staple cartridge  15080 . In at least one such instance, the anvil  15090  can comprise a second cam surface  15093  defined thereon which can be contacted by the crossbar  15181  of the carriage  15080  as the carriage  15080  is moved proximally by the closure drive lead screw  15170 . As the reader will appreciate, the closing cam surface  15092  can be defined on a first side of the pivot pin  15200  and the opening cam surface  15093  can be defined on a second, or opposite, side of the pivot pin  15200 . The opening cam surface  15093  can extend at an angle with respect to the closing cam surface  15092 . In various instances, the crossbar  15181  can contact and slide relative to the opening cam surface  15093  as the carriage  15180  is retracted. The opening cam surface  15093  can be configured such that the degree, or amount, in which the anvil  15090  is opened relative to the staple cartridge  15080  is dependent upon the distance in which the crossbar  15181  is retracted proximally. For instance, if the crossbar  15181  is retracted a first distance proximal to the pivot  15200 , the crossbar  15181  can pivot the anvil  15090  upwardly away from the staple cartridge  15080  a first degree and, if the crossbar  15181  is retracted a second distance proximal to the pivot  14200  which is larger than the first distance, the crossbar  15181  can pivot the anvil  15090  upwardly away from the staple cartridge  15080  a second degree which is larger than the first degree. 
     The closing system discussed above can permit the user of the surgical instrument to pivot the anvil  15090  between an open and a closed position without having to manipulate the anvil  15090  by hand. The closing system discussed above can also latch or lock the anvil  15090  in its closed position automatically without requiring the use of a separate actuator. To the extent that the user is unsatisfied with the positioning of the tissue between the anvil  15090  and the staple cartridge  15080  when the anvil  15090  is in its closed position, the user can reopen the anvil  15090 , reposition the anvil  15090  and the staple cartridge  15080  relative to the tissue, and then close the anvil  15090  once again. The user can open and close the anvil  15090  as many times as needed prior to actuating the firing system of the instrument  15010 . The firing system can comprise a firing motor  15120  mounted to the motor frame  15125 , a firing drive gear train operably coupled to the firing motor  15120  including a firing gear  15240 , a firing lead screw gear  15250 , and a firing drive lead screw  15260 . Similar to the above, the firing drive gear train and/or the firing drive lead screw  15260  can be rotatably supported by the motor frame  15125 . The firing drive can further comprise a firing trigger  15055  configured to close a firing switch  15290  when the firing trigger  15055  is depressed to operate the firing motor  15120 . When the firing motor  15120  is operated in a first direction to rotate the firing drive lead screw  15260  in a first direction, the firing drive can deploy the staples removably stored in the staple cartridge  15080  and incise the tissue captured between the anvil  15090  and the staple cartridge  15080 . When the firing motor  15120  is operated in a second direction to rotate the firing drive lead screw  15260  in a second, or opposite, direction, the firing drive can be retracted. Thereafter, the anvil  15090  can be reopened to remove the tissue from between the anvil  15090  and the staple cartridge  15080 . In some instances, the firing drive may not need to be retracted to open the anvil  15090 . In such instances, the firing drive may not engage the anvil  15090  as it is advanced distally. In at least one such instance, the firing drive can enter into the staple cartridge  15080  to eject the staples therefrom and a knife edge may travel between the staple cartridge  15080  and the anvil  15090  to incise the tissue. The firing drive may not lock the anvil  15090  in its closed position, although embodiments are envisioned in which the firing drive could lock the anvil  15090  in its closed position. Such embodiments could utilize an I-beam, for example, which can engage the anvil  15090  and the staple cartridge  15080  and hold them in position relative to each other as the I-beam is advanced distally. 
     The instrument  15010  can be powered by an external power source and/or an internal power source. A cable can enter into the actuator housing  15080  to supply power from an external power source, for example. One or more batteries, such as battery  15400 , for example, can be positioned within the handle of the instrument  15010  to supply power from an internal power source, for example. The instrument  15010  can further comprise one or more indicators, such as LED indicator  15100 , for example, which can indicate the operating state of the instrument  15010 , for example. The LED indicator  15100  can operate the same manner as or a similar manner to the LED indicator  11100  described above, for example. The LED indicator  15100  can be in signal communication with the microcontroller of the instrument  15010  which can be positioned on a printed circuit board  15500 , for example. 
     Previous surgical instruments have utilized a manually-driven closure system configured to move an anvil between an open position and a closed position. Various embodiments disclosed herein utilize a motor-driven closure system configured to move an anvil between an open position and a closed position relative to a fixed staple cartridge. Other embodiments are envisioned in which an anvil can be fixed and a motor-driven closure system could move a staple cartridge between an open position and a closed position. In either event, the motor of the closure system can set the tissue gap between the anvil and the staple cartridge. In various instances, the closure system of the surgical instrument is separate and distinct from the firing system. In other instances, the closure system and the firing system can be integral. When the closure system and the firing system are separate and distinct, the user of the surgical instrument can evaluate the position of the anvil and the staple cartridge relative to the tissue that is to be stapled and incised before operating the firing system. 
     As discussed above, an end effector of a surgical instrument, such as end effector  1000 , for example, can be configured to clamp tissue between an anvil jaw  1040  and a staple cartridge  1060  thereof. When the anvil jaw  1040  is in its closed position, a tissue gap can be defined between the anvil jaw  1040  and the staple cartridge  1060 . In certain instances, the end effector  1000  may be suitable for use with thin tissue, thick tissue, and tissue having a thickness intermediate the thin tissue and the thick tissue. The thinnest tissue and the thickest tissue in which the end effector  1000  can be suitably used to staple can define a tissue thickness range for the end effector  1000 . In various instances, a surgical instrument system can include a handle and a plurality of end effectors which can be assembled to the handle, wherein one or more of the end effectors can have different tissue thickness ranges. For instance, a first end effector can have a first tissue thickness range and a second end effector can have a second tissue thickness range which is different than the first tissue thickness range. In some instances, the first tissue thickness range and the second tissue thickness range can be discrete while, in other instances, the first tissue thickness range and the second tissue thickness range can partially overlap. Surgical instrument systems can utilize any suitable number of end effectors having different tissue thickness ranges where some of the tissue thickness ranges may at least partially overlap and other tissue thickness ranges may not overlap at all. 
     In various instances, further to the above, a staple cartridge of an end effector, such as staple cartridge  1060  of end effector  1000 , for example, can be replaceable. In various instances, the staple cartridge  1060  can be removably locked into position within the lower jaw  1020  of the end effector  1000 . Once locked into position, the deck, or tissue contacting, surface of the staple cartridge  1060  may not move, or at least substantially move, relative to the lower jaw  1020 . Thus, when the anvil jaw  1040  is moved into its closed position, a fixed distance, or tissue gap, can be defined between the anvil jaw  1040  and the deck surface of the staple cartridge  1060 . To change this fixed distance, the staple cartridge  1060  can be removed from the lower jaw  1020  and a different staple cartridge can be removably locked within the lower jaw  1020 . The deck surface of the different staple cartridge can be configured to provide a different tissue gap than the tissue gap provided by the staple cartridge  1060 . Embodiments are envisioned in which a surgical instrument system includes a handle, a plurality of end effectors which can be assembled to the handle, and a plurality of staple cartridges which can be replaceably inserted into the end effectors. Such an embodiment can allow a user to select an end effector capable of being used with a range of tissue thicknesses and the staple cartridge selected for use with the end effector can adjust or fine tune the range of tissue thicknesses that can be stapled by the end effector. In certain instances, a first staple cartridge of the surgical instrument system can include a first type of staple and a second staple cartridge can include a second type of staple. For example, the first staple cartridge can include staples having a first unformed, or unfired, height, and the second staple cartridge can include staples having a second unformed, or unfired, height which is different that the first height. 
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     U.S. patent application Ser. No. 13/800,025, entitled STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, filed on Mar. 13, 2013, now U.S. Pat. No. 9,345,481; 
     U.S. patent application Ser. No. 13/800,067, entitled STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, filed on Mar. 13, 2013, now U.S. Patent Application Publication No. 2014/0263552; 
     U.S. Patent Application Publication No. 2007/0175955, entitled SURGICAL CUTTING AND FASTENING INSTRUMENT WITH CLOSURE TRIGGER LOCKING MECHANISM, filed Jan. 31, 2006; and 
     U.S. Patent Application Publication No. 2010/0264194, entitled SURGICAL STAPLING INSTRUMENT WITH AN ARTICULATABLE END EFFECTOR, filed Apr. 22, 2010, now U.S. Pat. No. 8,308,040, are hereby incorporated by reference herein. 
     As described earlier, sensors may be configured to detect and collect data associated with the surgical device. The processor processes the sensor data received from the sensor(s). 
     The processor may be configured to execute operating logic. The processor may be any one of a number of single or multi-core processors known in the art. The storage may comprise volatile and non-volatile storage media configured to store persistent and temporal (working) copy of the operating logic. 
     In various embodiments, the operating logic may be configured to process the data associated with motion, as described above. In various embodiments, the operating logic may be configured to perform the initial processing, and transmit the data to the computer hosting the application to determine and generate instructions. For these embodiments, the operating logic may be further configured to receive information from and provide feedback to a hosting computer. In alternate embodiments, the operating logic may be configured to assume a larger role in receiving information and determining the feedback. In either case, whether determined on its own or responsive to instructions from a hosting computer, the operating logic may be further configured to control and provide feedback to the user. 
     In various embodiments, the operating logic may be implemented in instructions supported by the instruction set architecture (ISA) of the processor, or in higher level languages and compiled into the supported ISA. The operating logic may comprise one or more logic units or modules. The operating logic may be implemented in an object oriented manner. The operating logic may be configured to be executed in a multi-tasking and/or multi-thread manner. In other embodiments, the operating logic may be implemented in hardware such as a gate array. 
     In various embodiments, the communication interface may be configured to facilitate communication between a peripheral device and the computing system. The communication may include transmission of the collected biometric data associated with position, posture, and/or movement data of the user&#39;s body part(s) to a hosting computer, and transmission of data associated with the tactile feedback from the host computer to the peripheral device. In various embodiments, the communication interface may be a wired or a wireless communication interface. An example of a wired communication interface may include, but is not limited to, a Universal Serial Bus (USB) interface. An example of a wireless communication interface may include, but is not limited to, a Bluetooth interface. 
     For various embodiments, the processor may be packaged together with the operating logic. In various embodiments, the processor may be packaged together with the operating logic to form a System in Package (SiP). In various embodiments, the processor may be integrated on the same die with the operating logic. In various embodiments, the processor may be packaged together with the operating logic to form a System on Chip (SoC). 
     Various embodiments may be described herein in the general context of computer executable instructions, such as software, program modules, and/or engines being executed by a processor. Generally, software, program modules, and/or engines include any software element arranged to perform particular operations or implement particular abstract data types. Software, program modules, and/or engines can include routines, programs, objects, components, data structures and the like that perform particular tasks or implement particular abstract data types. An implementation of the software, program modules, and/or engines components and techniques may be stored on and/or transmitted across some form of computer-readable media. In this regard, computer-readable media can be any available medium or media useable to store information and accessible by a computing device. Some embodiments also may be practiced in distributed computing environments where operations are performed by one or more remote processing devices that are linked through a communications network. In a distributed computing environment, software, program modules, and/or engines may be located in both local and remote computer storage media including memory storage devices. A memory such as a random access memory (RAM) or other dynamic storage device may be employed for storing information and instructions to be executed by the processor. The memory also may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by the processor. 
     Although some embodiments may be illustrated and described as comprising functional components, software, engines, and/or modules performing various operations, it can be appreciated that such components or modules may be implemented by one or more hardware components, software components, and/or combination thereof. The functional components, software, engines, and/or modules may be implemented, for example, by logic (e.g., instructions, data, and/or code) to be executed by a logic device (e.g., processor). Such logic may be stored internally or externally to a logic device on one or more types of computer-readable storage media. In other embodiments, the functional components such as software, engines, and/or modules may be implemented by hardware elements that may include processors, microprocessors, circuits, circuit elements (e.g., transistors, resistors, capacitors, inductors, and so forth), integrated circuits, application specific integrated circuits (ASIC), programmable logic devices (PLD), digital signal processors (DSP), field programmable gate array (FPGA), logic gates, registers, semiconductor device, chips, microchips, chip sets, and so forth. 
     Examples of software, engines, and/or modules may include software components, programs, applications, computer programs, application programs, system programs, machine programs, operating system software, middleware, firmware, software modules, routines, subroutines, functions, methods, procedures, software interfaces, application program interfaces (API), instruction sets, computing code, computer code, code segments, computer code segments, words, values, symbols, or any combination thereof. Determining whether an embodiment is implemented using hardware elements and/or software elements may vary in accordance with any number of factors, such as desired computational rate, power levels, heat tolerances, processing cycle budget, input data rates, output data rates, memory resources, data bus speeds and other design or performance constraints. 
     One or more of the modules described herein may comprise one or more embedded applications implemented as firmware, software, hardware, or any combination thereof. One or more of the modules described herein may comprise various executable modules such as software, programs, data, drivers, application program interfaces (APIs), and so forth. The firmware may be stored in a memory of the controller  2016  and/or the controller  2022  which may comprise a nonvolatile memory (NVM), such as in bit-masked read-only memory (ROM) or flash memory. In various implementations, storing the firmware in ROM may preserve flash memory. The nonvolatile memory (NVM) may comprise other types of memory including, for example, programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or battery backed random-access memory (RAM) such as dynamic RAM (DRAM), Double-Data-Rate DRAM (DDRAM), and/or synchronous DRAM (SDRAM). 
     In some cases, various embodiments may be implemented as an article of manufacture. The article of manufacture may include a computer readable storage medium arranged to store logic, instructions and/or data for performing various operations of one or more embodiments. In various embodiments, for example, the article of manufacture may comprise a magnetic disk, optical disk, flash memory or firmware containing computer program instructions suitable for execution by a general purpose processor or application specific processor. The embodiments, however, are not limited in this context. 
     The functions of the various functional elements, logical blocks, modules, and circuits elements described in connection with the embodiments disclosed herein may be implemented in the general context of computer executable instructions, such as software, control modules, logic, and/or logic modules executed by the processing unit. Generally, software, control modules, logic, and/or logic modules comprise any software element arranged to perform particular operations. Software, control modules, logic, and/or logic modules can comprise routines, programs, objects, components, data structures and the like that perform particular tasks or implement particular abstract data types. An implementation of the software, control modules, logic, and/or logic modules and techniques may be stored on and/or transmitted across some form of computer-readable media. In this regard, computer-readable media can be any available medium or media useable to store information and accessible by a computing device. Some embodiments also may be practiced in distributed computing environments where operations are performed by one or more remote processing devices that are linked through a communications network. In a distributed computing environment, software, control modules, logic, and/or logic modules may be located in both local and remote computer storage media including memory storage devices. 
     Additionally, it is to be appreciated that the embodiments described herein illustrate example implementations, and that the functional elements, logical blocks, modules, and circuits elements may be implemented in various other ways which are consistent with the described embodiments. Furthermore, the operations performed by such functional elements, logical blocks, modules, and circuits elements may be combined and/or separated for a given implementation and may be performed by a greater number or fewer number of components or modules. As will be apparent to those of skill in the art upon reading the present disclosure, each of the individual embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several aspects without departing from the scope of the present disclosure. Any recited method can be carried out in the order of events recited or in any other order which is logically possible. 
     It is worthy to note that any reference to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is comprised in at least one embodiment. The appearances of the phrase “in one embodiment” or “in one aspect” in the specification are not necessarily all referring to the same embodiment. 
     Unless specifically stated otherwise, it may be appreciated that terms such as “processing,” “computing,” “calculating,” “determining,” or the like, refer to the action and/or processes of a computer or computing system, or similar electronic computing device, such as a general purpose processor, a DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein that manipulates and/or transforms data represented as physical quantities (e.g., electronic) within registers and/or memories into other data similarly represented as physical quantities within the memories, registers or other such information storage, transmission or display devices. 
     It is worthy to note that some embodiments may be described using the expression “coupled” and “connected” along with their derivatives. These terms are not intended as synonyms for each other. For example, some embodiments may be described using the terms “connected” and/or “coupled” to indicate that two or more elements are in direct physical or electrical contact with each other. The term “coupled,” however, also may mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other. With respect to software elements, for example, the term “coupled” may refer to interfaces, message interfaces, application program interface (API), exchanging messages, and so forth. 
     It should be appreciated that any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material. 
     The disclosed embodiments have application in conventional endoscopic and open surgical instrumentation as well as application in robotic-assisted surgery. 
     Embodiments of the devices disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. Embodiments may, in either or both cases, be reconditioned for reuse after at least one use. Reconditioning may include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces, and subsequent reassembly. In particular, embodiments of the device may be disassembled, and any number of the particular pieces or parts of the device may be selectively replaced or removed in any combination. Upon cleaning and/or replacement of particular parts, embodiments of the device may be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of a device may utilize a variety of techniques for disassembly, cleaning/replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application. 
     By way of example only, embodiments described herein may be processed before surgery. First, a new or used instrument may be obtained and when necessary cleaned. The instrument may then be sterilized. In one sterilization technique, the instrument is placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and instrument may then be placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation may kill bacteria on the instrument and in the container. The sterilized instrument may then be stored in the sterile container. The sealed container may keep the instrument sterile until it is opened in a medical facility. A device may also be sterilized using any other technique known in the art, including but not limited to beta or gamma radiation, ethylene oxide, or steam. 
     One skilled in the art will recognize that the herein described components (e.g., operations), devices, objects, and the discussion accompanying them are used as examples for the sake of conceptual clarity and that various configuration modifications are contemplated. Consequently, as used herein, the specific exemplars set forth and the accompanying discussion are intended to be representative of their more general classes. In general, use of any specific exemplar is intended to be representative of its class, and the non-inclusion of specific components (e.g., operations), devices, and objects should not be taken limiting. 
     With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations are not expressly set forth herein for sake of clarity. 
     The herein described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples and that in fact many other architectures may be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “operably connected,” or “operably coupled,” to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being “operably couplable,” to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components, and/or wirelessly interactable, and/or wirelessly interacting components, and/or logically interacting, and/or logically interactable components. 
     Some aspects may be described using the expression “coupled” and “connected” along with their derivatives. It should be understood that these terms are not intended as synonyms for each other. For example, some aspects may be described using the term “connected” to indicate that two or more elements are in direct physical or electrical contact with each other. In another example, some aspects may be described using the term “coupled” to indicate that two or more elements are in direct physical or electrical contact. The term “coupled,” however, also may mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other. 
     In some instances, one or more components may be referred to herein as “configured to,” “configurable to,” “operable/operative to,” “adapted/adaptable,” “able to,” “conformable/conformed to,” etc. Those skilled in the art will recognize that “configured to” can generally encompass active-state components and/or inactive-state components and/or standby-state components, unless context requires otherwise. 
     While particular aspects of the present subject matter described herein have been shown and described, it will be apparent to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from the subject matter described herein and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true scope of the subject matter described herein. It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that when a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to claims containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. 
     In addition, even when a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that typically a disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms unless context dictates otherwise. For example, the phrase “A or B” will be typically understood to include the possibilities of “A” or “B” or “A and B.” 
     With respect to the appended claims, those skilled in the art will appreciate that recited operations therein may generally be performed in any order. Also, although various operational flows are presented in a sequence(s), it should be understood that the various operations may be performed in other orders than those which are illustrated, or may be performed concurrently. Examples of such alternate orderings may include overlapping, interleaved, interrupted, reordered, incremental, preparatory, supplemental, simultaneous, reverse, or other variant orderings, unless context dictates otherwise. Furthermore, terms like “responsive to,” “related to,” or other past-tense adjectives are generally not intended to exclude such variants, unless context dictates otherwise. 
     In summary, numerous benefits have been described which result from employing the concepts described herein. The foregoing description of the one or more embodiments has been presented for purposes of illustration and description. It is not intended to be exhaustive or limiting to the precise form disclosed. Modifications or variations are possible in light of the above teachings. The one or more embodiments were chosen and described in order to illustrate principles and practical application to thereby enable one of ordinary skill in the art to utilize the various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the claims submitted herewith define the overall scope.