Patent Publication Number: US-10779825-B2

Title: Adapters with end effector position sensing and control arrangements for use in connection with electromechanical surgical instruments

Description:
BACKGROUND 
     The present invention relates to surgical instruments and, in various arrangements, to surgical stapling and cutting instruments and staple cartridges for use therewith that are designed to staple and cut tissue. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various features of the embodiments described herein, together with advantages thereof, may be understood in accordance with the following description taken in conjunction with the accompanying drawings as follows: 
         FIG. 1  is a perspective view of an electromechanical surgical system; 
         FIG. 2  is a perspective view of a distal end of an electromechanical surgical instrument portion of the surgical system of  FIG. 1 ; 
         FIG. 3  is an exploded assembly view of an outer shell feature and the electromechanical surgical instrument of  FIG. 2 ; 
         FIG. 4  is a rear perspective view of a portion of the electromechanical surgical instrument of  FIG. 2 ; 
         FIG. 5  is a partial exploded assembly view of a portion of an adapter and the electromechanical surgical instrument of the surgical system of  FIG. 1 ; 
         FIG. 6  is an exploded assembly view of a portion of the adapter of  FIG. 5 ; 
         FIG. 7  is a cross-sectional perspective view of a portion of an articulation assembly of an adapter; 
         FIG. 8  is a perspective view of the articulation assembly of  FIG. 7 ; 
         FIG. 9  is another perspective view of the articulation assembly of  FIG. 8 ; 
         FIG. 10  is an exploded assembly view of a loading unit employed in the electromechanical surgical system of  FIG. 1 ; 
         FIG. 11  is a perspective view of an alternative adapter embodiment; 
         FIG. 12  is a side elevational view of a portion of a loading unit of the adapter of  FIG. 11  with the jaws thereof in an open position; 
         FIG. 13  is another side elevational view of a portion of the loading unit of  FIG. 11  with portions thereof shown in cross-section and the jaws thereof in a closed position; 
         FIG. 14  is a bottom view of a portion of the loading unit of  FIG. 13  with portions thereof shown in cross-section; 
         FIG. 15  is a perspective view of a portion of the loading unit of  FIG. 14  with a portion of the outer tube shown in phantom lines; 
         FIG. 16  is a cross-sectional view of a proximal portion of another adapter employing various seal arrangements therein; 
         FIG. 17  is an end cross-sectional view of a portion of the adapter of  FIG. 16 ; 
         FIG. 18  is a side elevation al view of another adapter; 
         FIG. 19  is a cross-sectional view of a portion of the adapter of  FIG. 18 ; 
         FIG. 20  is a rear perspective view of portions of another adapter; 
         FIG. 21  is a cross-sectional view of another adapter; 
         FIG. 22  is a top view of a loading unit of an adapter with the tool assembly thereof in an unarticulated position; 
         FIG. 23  is another top view of the loading unit of  FIG. 22  with the tool assembly in a first articulated position; 
         FIG. 24  is another top view of the loading unit of  FIGS. 22 and 23  with the tool assembly in a second articulated position; 
         FIG. 25  is a perspective view of a portion of an adapter; 
         FIG. 26  is a perspective view of another portion of an adapter; 
         FIG. 27  is a partial cross-sectional perspective view of an articulation system and sensor assembly embodiment of an adapter in an unarticulated (neutral) position; 
         FIG. 28  is another perspective view of the articulation system and sensor assembly of  FIG. 27  in a first articulated position; 
         FIG. 29  is another perspective view of the articulation system and sensor assembly of  FIGS. 27 and 28  in a second articulated position; 
         FIG. 30  is a partial cross-sectional view a portion of an alternative proximal drive shaft and bearing housing of an alternative articulation system in an unarticulated (neutral) position; 
         FIG. 31  is another partial cross-sectional view the portion of an alternative proximal drive shaft and bearing housing of the alternative articulation system of  FIG. 30  in an articulated position; 
         FIG. 32  is a partial cross-sectional view a portion of an alternative proximal drive shaft and bearing housing of an alternative articulation system in an unarticulated (neutral) position; 
         FIG. 33  is another partial cross-sectional view the portion of an alternative proximal drive shaft and bearing housing of the alternative articulation system of  FIG. 32  in an articulated position; 
         FIG. 34  is a partial cross-sectional perspective view of another articulation system and sensor assembly embodiment of an adapter in an unarticulated (neutral) position; 
         FIG. 35  is a partial cross-sectional side view of the articulation system and sensor assembly embodiment of an adapter of  FIG. 34  in the unarticulated (neutral) position; 
         FIG. 36  is another partial cross-sectional side view of the articulation system and sensor assembly embodiment of an adapter of  FIGS. 34 and 35  in an articulated position; 
         FIG. 37  is another partial cross-sectional side view of the articulation system and sensor assembly embodiment of an adapter of  FIGS. 34-36  in another articulated position; and 
         FIG. 38  is a perspective view of portions of an articulation system and sensor system and a shaft rotation system and sensor arrangement of another adapter. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate various 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 U.S. patent applications that were filed on Dec. 15, 2017 and which are each herein incorporated by reference in their respective entireties:
         U.S. patent application Ser. No. 15/843,485, entitled SEALED ADAPTERS FOR USE WITH ELECTROMECHANICAL SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2019/0183492;   U.S. patent application Ser. No. 15/843,518, entitled END EFFECTORS WITH POSITIVE JAW OPENING FEATURES FOR USE WITH ADAPTERS FOR ELECTROMECHANICAL SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2019/0183496;   U.S. patent application Ser. No. 15/843,535, entitled SURGICAL END EFFECTORS WITH CLAMPING ASSEMBLIES CONFIGURED TO INCREASE JAW APERTURE RANGES, now U.S. Patent Application Publication No. 2019/0183498;   U.S. patent application Ser. No. 15/843,558, entitled SURGICAL END EFFECTORS WITH PIVOTAL JAWS CONFIGURED TO TOUCH AT THEIR RESPECTIVE DISTAL ENDS WHEN FULLY CLOSED, now U.S. Patent Application Publication No. 2019/0183499;   U.S. patent application Ser. No. 15/843,528, entitled SURGICAL END EFFECTORS WITH JAW STIFFENER ARRANGEMENTS CONFIGURED TO PERMIT MONITORING OF FIRING MEMBER, now U.S. Patent Application Publication No. 2019/0183497;   U.S. patent application Ser. No. 15/843,556, entitled DYNAMIC CLAMPING ASSEMBLIES WITH IMPROVED WEAR CHARACTERISTICS FOR USE IN CONNECTION WITH ELECTROMECHANICAL SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2019/0183490;   U.S. patent application Ser. No. 15/843,514, entitled ADAPTERS WITH FIRING STROKE SENSING ARRANGEMENTS FOR USE IN CONNECTION WITH ELECTROMECHANICAL SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2019/0183495;   U.S. patent application Ser. No. 15/843,501, entitled ADAPTERS WITH CONTROL SYSTEMS FOR CONTROLLING MULTIPLE MOTORS OF AN ELECTROMECHANICAL SURGICAL INSTRUMENT, now U.S. Patent Application Publication No. 2019/0183493;   U.S. patent application Ser. No. 15/843,508, entitled HANDHELD ELECTROMECHANICAL SURGICAL INSTRUMENTS WITH IMPROVED MOTOR CONTROL ARRANGEMENTS FOR POSITIONING COMPONENTS OF AN ADAPTER COUPLED THERETO, now U.S. Patent Application Publication No. 2019/0183494;   U.S. patent application Ser. No. 15/843,682, entitled SYSTEMS AND METHODS OF CONTROLLING A CLAMPING MEMBER FIRING RATE OF A SURGICAL INSTRUMENT, now U.S. Patent Application Publication No. 2019/0183501;   U.S. patent application Ser. No. 15/843,689, entitled SYSTEMS AND METHODS OF CONTROLLING A CLAMPING MEMBER, now U.S. Patent Application Publication No. 2019/0183502; and   U.S. patent application Ser. No. 15/843,704, entitled METHODS OF OPERATING SURGICAL END EFFECTORS, now U.S. Patent Application Publication No. 2019/0183503.       

     Numerous specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture, and use of the embodiments as described in the specification and illustrated in the accompanying drawings. Well-known operations, components, and elements have not been described in detail so as not to obscure the embodiments described in the specification. The reader will understand that the embodiments described and illustrated herein are non-limiting examples, and thus it can be appreciated that the specific structural and functional details disclosed herein may be representative and illustrative. Variations and changes thereto may be made without departing from the scope of the claims. 
     The terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include” (and any form of include, such as “includes” and “including”) and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, a surgical system, device, or apparatus that “comprises,” “has,” “includes” or “contains” one or more elements possesses those one or more elements, but is not limited to possessing only those one or more elements. Likewise, an element of a system, device, or apparatus that “comprises,” “has,” “includes” or “contains” one or more features possesses those one or more features, but is not limited to possessing only those one or more features. 
     The terms “proximal” and “distal” are used herein with reference to a clinician manipulating the handle portion of the surgical instrument. The term “proximal” refers to the portion closest to the clinician and the term “distal” refers 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 reader 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, the reader 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 elongate shaft of a surgical instrument can be advanced. 
     A surgical stapling system can comprise a shaft and an end effector extending from the shaft. The end effector comprises a first jaw and a second jaw. The first jaw comprises a staple cartridge. The staple cartridge is insertable into and removable from the first jaw; however, other embodiments are envisioned in which a staple cartridge is not removable from, or at least readily replaceable from, the first jaw. The second jaw comprises an anvil configured to deform staples ejected from the staple cartridge. The second jaw is pivotable relative to the first jaw about a closure axis; however, other embodiments are envisioned in which the first jaw is pivotable relative to the second jaw. The surgical stapling system further comprises an articulation joint configured to permit the end effector to be rotated, or articulated, relative to the shaft. The end effector is rotatable about an articulation axis extending through the articulation joint. Other embodiments are envisioned which do not include an articulation joint. 
     The staple cartridge comprises a cartridge body. The cartridge body includes a proximal end, a distal end, and a deck extending between the proximal end and the distal end. In use, the staple cartridge is positioned on a first side of the tissue to be stapled and the anvil is positioned on a second side of the tissue. The anvil is moved toward the staple cartridge to compress and clamp the tissue against the deck. Thereafter, staples removably stored in the cartridge body can be deployed into the tissue. The cartridge body includes staple cavities defined therein wherein staples are removably stored in the staple cavities. The staple cavities are arranged in six longitudinal rows. Three rows of staple cavities are positioned on a first side of a longitudinal slot and three rows of staple cavities are positioned on a second side of the longitudinal slot. Other arrangements of staple cavities and staples may be possible. 
     The staples are supported by staple drivers in the cartridge body. The drivers are movable between a first, or unfired position, and a second, or fired, position to eject the staples from the staple cavities. The drivers are retained in the cartridge body by a retainer which extends around the bottom of the cartridge body and includes resilient members configured to grip the cartridge body and hold the retainer to the cartridge body. The drivers are movable between their unfired positions and their fired positions by a sled. The sled is movable between a proximal position adjacent the proximal end and a distal position adjacent the distal end. The sled comprises a plurality of ramped surfaces configured to slide under the drivers and lift the drivers, and the staples supported thereon, toward the anvil. 
     Further to the above, the sled is moved distally by a firing member. The firing member is configured to contact the sled and push the sled toward the distal end. The longitudinal slot defined in the cartridge body is configured to receive the firing member. The anvil also includes a slot configured to receive the firing member. The firing member further comprises a first cam which engages the first jaw and a second cam which engages the second jaw. As the firing member is advanced distally, the first cam and the second cam can control the distance, or tissue gap, between the deck of the staple cartridge and the anvil. The firing member also comprises a knife configured to incise the tissue captured intermediate the staple cartridge and the anvil. It is desirable for the knife to be positioned at least partially proximal to the ramped surfaces such that the staples are ejected ahead of the knife. 
       FIG. 1  depicts a motor-driven (electromechanical) surgical system  1  that may be used to perform a variety of different surgical procedures. As can be seen in that Figure, one example of the surgical system  1  includes a powered handheld electromechanical surgical instrument  100  that is configured for selective attachment thereto of a plurality of different surgical tool implements (referred to herein as “adapters”) that are each configured for actuation and manipulation by the powered handheld electromechanical surgical instrument. As illustrated in  FIG. 1 , the handheld surgical instrument  100  is configured for selective connection with an adapter  200 , and, in turn, adapter  200  is configured for selective connection with end effectors that comprise a single use loading unit (“SULU”) or a disposable loading unit (“DLU”) or a multiple use loading unit (“MULU”). In another surgical system embodiment, various forms of adapter  200  may also be effectively employed with a tool drive assembly of a robotically controlled or automated surgical system. For example, the surgical tool assemblies disclosed herein may be employed with various robotic systems, instruments, components and methods such as, but not limited to, those disclosed in U.S. Pat. No. 9,072,535, entitled SURGICAL STAPLING INSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENT ARRANGEMENTS, which is hereby incorporated by reference herein in its entirety. 
     As illustrated in  FIGS. 1 and 2 , surgical instrument  100  includes a power-pack  101  and an outer shell housing  10  that is configured to selectively receive and substantially encase the power-pack  101 . The power pack  101  may also be referred to herein as handle assembly  101 . One form of surgical instrument  100 , for example, is disclosed in International Publication No. WO 2016/057225 A1, International Application No. PCT/US2015/051837, entitled HANDHELD ELECTROMECHANICAL SURGICAL SYSTEM, the entire disclosure of which is hereby incorporated by reference herein. Various features of surgical instrument  100  will not be disclosed herein beyond what is necessary to understand the various features of the inventions disclosed herein with it being understood that further details may be gleaned from reference to WO 2016/057225 A1 and other references incorporated by reference herein. 
     As illustrated in  FIG. 3 , outer shell housing  10  includes a distal half-section  10   a  and a proximal half-section  10   b  that is pivotably connected to distal half-section  10   a  by a hinge  16  located along an upper edge of distal half-section  10   a  and proximal half-section  10   b . When joined, distal and proximal half-sections  10   a ,  10   b  define a shell cavity  10   c  therein in which the power-pack  101  is selectively situated. Each of distal and proximal half-sections  10   a ,  10   b  includes a respective upper shell portion  12   a ,  12   b , and a respective lower shell portion  14   a ,  14   b . Lower shell portions  14   a ,  14   b  define a snap closure feature  18  for selectively securing the lower shell portions  14   a ,  14   b  to one another and for maintaining shell housing  10  in a closed condition. Distal half-section  10   a  of shell housing  10  defines a connecting portion  20  that is configured to accept a corresponding drive coupling assembly  210  of adapter  200  (see  FIG. 5 ). Specifically, distal half-section  10   a  of shell housing  10  has a recess that receives a portion of drive coupling assembly  210  of adapter  200  when adapter  200  is mated to surgical instrument  100 . 
     Connecting portion  20  of distal half-section  10   a  defines a pair of axially extending guide rails  21   a ,  21   b  that project radially inward from inner side surfaces thereof as shown in  FIG. 5 . Guide rails  21   a ,  21   b  assist in rotationally orienting adapter  200  relative to surgical instrument  100  when adapter  200  is mated to surgical instrument  100 . Connecting portion  20  of distal half-section  10   a  defines three apertures  22   a ,  22   b ,  22   c  that are formed in a distally facing surface thereof and which are arranged in a common plane or line with one another. Connecting portion  20  of distal half-section  10   a  also defines an elongate slot  24  also formed in the distally facing surface thereof. Connecting portion  20  of distal half-section  10   a  further defines a female connecting feature  26  (see  FIG. 2 ) formed in a surface thereof. Female connecting feature  26  selectively engages with a male connecting feature of adapter  200 . 
     Distal half-section  10   a  of shell housing  10  supports a distal facing toggle control button  30 . The toggle control button  30  is capable of being actuated in a left, right, up and down direction upon application of a corresponding force thereto or a depressive force thereto. Distal half-section  10   a  of shell housing  10  supports a right-side pair of control buttons  32   a ,  32   b  (see  FIG. 3 ); and a left-side pair of control button  34   a ,  34   b  (see  FIG. 2 ). The right-side control buttons  32   a ,  32   b  and the left-side control buttons  34   a ,  34   b  are capable of being actuated upon application of a corresponding force thereto or a depressive force thereto. Proximal half-section  10   b  of shell housing  10  supports a right-side control button  36   a  (see  FIG. 3 ) and a left-side control button  36   b  (see  FIG. 2 ). Right-side control button  36   a  and left-side control button  36   b  are capable of being actuated upon application of a corresponding force thereto or a depressive force thereto. 
     Shell housing  10  includes a sterile barrier plate assembly  60  selectively supported in distal half-section  10   a . Specifically, the sterile barrier plate assembly  60  is disposed behind connecting portion  20  of distal half-section  10   a  and within shell cavity  10   c  of shell housing  10 . The plate assembly  60  includes a plate  62  rotatably supporting three coupling shafts  64   a ,  64   b ,  64   c  (see  FIGS. 3 and 5 ). Each coupling shaft  64   a ,  64   b ,  64   c  extends from opposed sides of plate  62  and has a tri-lobe transverse cross-sectional profile. Each coupling shaft  64   a ,  64   b ,  64   c  extends through the respective apertures  22   a ,  22   b ,  22   c  of connecting portion  20  of distal half-section  10   a  when the sterile barrier plate assembly  60  is disposed within shell cavity  10   c  of shell housing  10 . The plate assembly  60  further includes an electrical pass-through connector  66  supported on plate  62 . Pass-through connector  66  extends from opposed sides of plate  62 . Pass-through connector  66  defines a plurality of contact paths each including an electrical conduit for extending an electrical connection across plate  62 . When the plate assembly  60  is disposed within shell cavity  10   c  of shell housing  10 , distal ends of coupling shaft  64   a ,  64   b ,  64   c  and a distal end of pass-through connector  66  are disposed or situated within connecting portion  20  of distal half-section  10   a  of shell housing  10 , and are configured to electrically and/or mechanically engage respective corresponding features of adapter  200 . 
     Referring to  FIGS. 3 and 4 , the power-pack or the handle assembly  101  includes an inner handle housing  110  having a lower housing portion  104  and an upper housing portion  108  extending from and/or supported on lower housing portion  104 . Lower housing portion  104  and upper housing portion  108  are separated into a distal half section  110   a  and a proximal half-section  110   b  connectable to distal half-section  110   a  by a plurality of fasteners. When joined, distal and proximal half-sections  110   a ,  110   b  define the inner handle housing  110  having an inner housing cavity  110   c  therein in which a power-pack core assembly  106  is situated. Power-pack core assembly  106  is configured to control the various operations of surgical instrument  100 . 
     Distal half-section  110   a  of inner handle housing  110  supports a distal toggle control interface  130  that is in operative registration with the distal toggle control button  30  of shell housing  10 . In use, when the power-pack  101  is disposed within shell housing  10 , actuation of the toggle control button  30  exerts a force on toggle control interface  130 . Distal half-section  110   a  of inner handle housing  110  also supports a right-side pair of control interfaces (not shown), and a left-side pair of control interfaces  132   a ,  132   b . In use, when the power-pack  101  is disposed within shell housing  10 , actuation of one of the right-side pair of control buttons or the left-side pair of control button of distal half-section  10   a  of shell housing  10  exerts a force on a respective one of the right-side pair of control interfaces  132   a ,  132   b  or the left-side pair of control interfaces  132   a ,  132   b  of distal half-section  110   a  of inner handle housing  110 . 
     With reference to  FIGS. 1-5 , inner handle housing  110  provides a housing in which power-pack core assembly  106  is situated. Power-pack core assembly  106  includes a battery circuit  140 , a controller circuit board  142  and a rechargeable battery  144  configured to supply power to any of the electrical components of surgical instrument  100 . Controller circuit board  142  includes a motor controller circuit board  142   a , a main controller circuit board  142   b , and a first ribbon cable  142   c  interconnecting motor controller circuit board  142   a  and main controller circuit board  142   b . Power-pack core assembly  106  further includes a display screen  146  supported on main controller circuit board  142   b . Display screen  146  is visible through a clear or transparent window  110   d  (see  FIG. 3 ) provided in proximal half-section  110   b  of inner handle housing  110 . It is contemplated that at least a portion of inner handle housing  110  may be fabricated from a transparent rigid plastic or the like. It is further contemplated that shell housing  10  may either include a window formed therein (in visual registration with display screen  146  and with window  110   d  of proximal half-section  110   b  of inner handle housing  110 , and/or shell housing  10  may be fabricated from a transparent rigid plastic or the like. 
     Power-pack core assembly  106  further includes a first motor  152 , a second motor  154 , and a third motor  156  that are supported by motor bracket  148  and are each electrically connected to controller circuit board  142  and battery  144 . Motors  152 ,  154 ,  156  are disposed between motor controller circuit board  142   a  and main controller circuit board  142   b . Each motor  152 ,  154 ,  156  includes a respective motor shaft  152   a ,  154   a ,  156   a  extending therefrom. Each motor shaft  152   a ,  154   a ,  156   a  has a tri-lobe transverse cross-sectional profile for transmitting rotative forces or torque. Each motor  152 ,  154 ,  156  is controlled by a respective motor controller. Rotation of motor shafts  152   a ,  154   a ,  156   a  by respective motors  152 ,  154 ,  156  function to drive shafts and/or gear components of adapter  200  in order to perform the various operations of surgical instrument  100 . In particular, motors  152 ,  154 ,  156  of power-pack core assembly  106  are configured to drive shafts and/or gear components of adapter  200 . 
     As illustrated in  FIGS. 1 and 5 , surgical instrument  100  is configured for selective connection with adapter  200 , and, in turn, adapter  200  is configured for selective connection with end effector  500 . Adapter  200  includes an outer knob housing  202  and an outer tube  206  that extends from a distal end of knob housing  202 . Knob housing  202  and outer tube  206  are configured and dimensioned to house the components of adapter assembly  200 . Outer tube  206  is dimensioned for endoscopic insertion, in particular, that outer tube is passable through a typical trocar port, cannula or the like. Knob housing  202  is dimensioned to not enter the trocar port, cannula of the like. Knob housing  202  is configured and adapted to connect to connecting portion  20  of the outer shell housing  10  of surgical instrument  100 . 
     Adapter  200  is configured to convert a rotation of either of first or second coupling shafts  64   a ,  64   b  of surgical instrument  100  into axial translation useful for operating a drive assembly  540  and an articulation link  560  of end effector  500 , as illustrated in  FIG. 10  and as will be described in greater detail below. As illustrated in  FIG. 6 , adapter  200  includes the proximal inner housing assembly  204  that rotatably supports a first rotatable proximal drive shaft  212 , a second rotatable proximal drive shaft  214 , and a third rotatable proximal drive shaft  216  therein. Each proximal drive shaft  212 ,  214 ,  216  functions as a rotation receiving member to receive rotational forces from respective coupling shafts  64   a ,  64   b  and  64   c  of surgical instrument  100 . In addition, the drive coupling assembly  210  of adapter  200  is also configured to rotatably support first, second and third connector sleeves  218 ,  220  and  222 , respectively, arranged in a common plane or line with one another. Each connector sleeve  218 ,  220 ,  222  is configured to mate with respective first, second and third coupling shafts  64   a ,  64   b ,  64   c  of surgical instrument  100 , as described above. Each connector sleeves  218 ,  222 ,  220  is further configured to mate with a proximal end of respective first, second, and third proximal drive shafts  212 ,  214 ,  216  of adapter  200 . 
     Drive coupling assembly  210  of adapter  200  also includes a first, a second, and a third biasing member  224 ,  226 , and  228  disposed distally of respective first, second, and third connector sleeves  218 ,  220 ,  222 . Each biasing members  224 ,  226 , and  228  is disposed about respective first, second, and third rotatable proximal drive shaft  212 ,  214 , and  216 . Biasing members  224 ,  226 , and  228  act on respective connector sleeves  218 ,  222 , and  220  to help maintain connector sleeves  218 ,  222 . and  220  engaged with the distal end of respective coupling shafts  64   a ,  64   b , and  64   c  of surgical instrument  100  when adapter  200  is connected to surgical instrument  100 . 
     Also in the illustrated arrangement, adapter  200  includes first, second, and third drive converting assemblies  240 ,  250 ,  260 , respectively, that are each disposed within inner housing assembly  204  and outer tube  206 . Each drive converting assembly  240 ,  250 ,  260  is configured and adapted to transmit or convert a rotation of a first, second, and third coupling shafts  64   a ,  64   b , and  64   c  of surgical instrument  100  into axial translation of an articulation driver or bar  258  of adapter  200 , to effectuate articulation of end effector  500 ; a rotation of a ring gear  266  of adapter  200 , to effectuate rotation of adapter  200 ; or axial translation of a distal drive member  248  of adapter  200  to effectuate closing, opening, and firing of end effector  500 . 
     Still referring to  FIG. 6 , first force/rotation transmitting/converting assembly  240  includes first rotatable proximal drive shaft  212 , which, as described above, is rotatably supported within inner housing assembly  204 . First rotatable proximal drive shaft  212  includes a non-circular or shaped proximal end portion configured for connection with first connector sleeve  218  which is connected to respective first coupling shaft  64   a  of surgical instrument  100 . First rotatable proximal drive shaft  212  includes a threaded distal end portion  212   b . First force/rotation transmitting/converting assembly  240  further includes a drive coupling nut  244  that threadably engages the threaded distal end portion  212   b  of first rotatable proximal drive shaft  212 , and which is slidably disposed within outer tube  206 . Drive coupling nut  244  is slidably keyed within proximal core tube portion of outer tube  206  so as to be prevented from rotation as first rotatable proximal drive shaft  212  is rotated. In this manner, as the first rotatable proximal drive shaft  212  is rotated, drive coupling nut  244  is translated along threaded distal end portion  212   b  of first rotatable proximal drive shaft  212  and, in turn, through and/or along outer tube  206 . 
     First force/rotation transmitting/converting assembly  240  further includes a distal drive member  248  that is mechanically engaged with drive coupling nut  244 , such that axial movement of drive coupling nut  244  results in a corresponding amount of axial movement of distal drive member  248 . The distal end portion of distal drive member  248  supports a connection member  247  configured and dimensioned for selective engagement with an engagement member  546  of a drive assembly  540  of end effector  500  ( FIG. 10 ). Drive coupling nut  244  and/or distal drive member  248  function as a force transmitting member to components of end effector  500 . In operation, as first rotatable proximal drive shaft  212  is rotated, as a result of the rotation of first coupling shaft  64   a  of surgical instrument  100 , drive coupling nut  244  is translated axially along first rotatable proximal drive shaft  212 . As drive coupling nut  244  is translated axially along first rotatable proximal drive shaft  212 , distal drive member  248  is translated axially relative to outer tube  206 . As distal drive member  248  is translated axially, with connection member  247  connected thereto and engaged with a hollow drive member  548  attached to drive assembly  540  of end effector  500  ( FIG. 10 ), distal drive member  248  causes concomitant axial translation of drive assembly  540  of end effector  500  to effectuate a closure of a tool assembly portion  600  of the end effector  500  and a firing of various components within the tool assembly. 
     Still referring to  FIG. 6 , second drive converting assembly  250  of adapter  200  includes second proximal drive shaft  214  that is rotatably supported within inner housing assembly  204 . Second rotatable proximal drive shaft  214  includes a non-circular or shaped proximal end portion configured for connection with second coupling shaft  64   c  of surgical instrument  100 . Second rotatable proximal drive shaft  214  further includes a threaded distal end portion  214   a  configured to threadably engage an articulation bearing housing  253  of an articulation bearing assembly  252 . Referring to  FIGS. 6-9 , the articulation bearing housing  253  supports an articulation bearing  255  that has an inner race  257  that is independently rotatable relative to an outer race  259 . Articulation bearing housing  253  has a non-circular outer profile, for example tear-dropped shaped, that is slidably and non-rotatably disposed within a complementary bore (not shown) of inner housing hub  204   a . Second drive converting assembly  250  of adapter  200  further includes articulation bar  258  that has a proximal portion that is secured to inner race  257  of articulation bearing  255 . A distal portion of articulation bar  258  includes a slot  258   a  therein, which is configured to accept a hook  562  the articulation link  560  ( FIG. 10 ) of end effector  500 . Articulation bar  258  functions as a force transmitting member to components of end effector  500 . In the illustrated arrangement and as further discussed in WO 2016/057225 A1, articulation bearing assembly  252  is both rotatable and longitudinally translatable and is configured to permit free, unimpeded rotational movement of end effector  500  when its first and second jaw members  610 ,  700  are in an approximated position and/or when jaw members  610 ,  700  are articulated. 
     In operation, as second proximal drive shaft  214  is rotated, the articulation bearing assembly  252  is axially translated along threaded distal end portion  214   a  of second proximal drive shaft  214 , which in turn, causes articulation bar  258  to be axially translated relative to outer tube  206 . As articulation bar  258  is translated axially, articulation bar  258 , being coupled to articulation link  560  of end effector  500 , causes concomitant axial translation of articulation link  560  of end effector  500  to effectuate an articulation of tool assembly  600 . Articulation bar  258  is secured to inner race  257  of articulation bearing  253  and is thus free to rotate about the longitudinal axis relative to outer race  259  of articulation bearing  253 . 
     As illustrated in  FIG. 6 , adapter  200  includes a third drive converting assembly  260  that is supported in inner housing assembly  204 . Third drive converting assembly  260  includes rotation ring gear  266  that is fixedly supported in and connected to outer knob housing  202 . Ring gear  266  defines an internal array of gear teeth  266   a  and includes a pair of diametrically opposed, radially extending protrusions  266   b . Protrusions  266   b  are configured to be disposed within recesses defined in outer knob housing  202 , such that rotation of ring gear  266  results in rotation of outer knob housing  202 , and vice a versa. Third drive converting assembly  260  further includes third rotatable proximal drive shaft  216  which, as described above, is rotatably supported within inner housing assembly  204 . Third rotatable proximal drive shaft  216  includes a non-circular or shaped proximal end portion that is configured for connection with third connector  220 . Third rotatable proximal drive shaft  216  includes a spur gear  216  keyed to a distal end thereof. A reversing spur gear  264  inter-engages spur gear  216   a  of third rotatable proximal drive shaft  216  to gear teeth  266   a  of ring gear  266 . In operation, as third rotatable proximal drive shaft  216  is rotated, due to a rotation of the third coupling shaft  64   b  of surgical instrument  100 , spur gear  216   a  of third rotatable proximal drive shaft  216  engages reversing gear  264  causing reversing gear  264  to rotate. As reversing gear  264  rotates, ring gear  266  also rotates thereby causing outer knob housing  202  to rotate. Rotation of the outer knob housing  202  causes the outer tube  206  to rotate about longitudinal axis of adapter  200 . As outer tube  206  is rotated, end effector  500  that is connected to a distal end portion of adapter  200 , is also rotated about a longitudinal axis of adapter  200 . 
     Adapter  200  further includes an attachment/detachment button  272  ( FIG. 5 ) that is supported on a stem  273  ( FIG. 6 ) that projects from drive coupling assembly  210  of adapter  200 . The attachment/detachment button  272  is biased by a biasing member (not shown) that is disposed within or around stem  273 , to an un-actuated condition. Button  272  includes a lip or ledge that is configured to snap behind a corresponding lip or ledge of connecting portion  20  of the surgical instrument  100 . As also discussed in WO 2016/057225 A1, the adapter  200  may further include a lock mechanism  280  for fixing the axial position of distal drive member  248 . As can be seen in  FIG. 21 , for example, lock mechanism  280  includes a button  282  that is slidably supported on outer knob housing  202 . Lock button  282  is connected to an actuation bar (not shown) that extends longitudinally through outer tube  206 . Actuation bar moves upon a movement of lock button  282 . In operation, in order to lock the position and/or orientation of distal drive member  248 , a user moves lock button  282  from a distal position to a proximal position, thereby causing the lock out (not shown) to move proximally such that a distal face of the lock out moves out of contact with camming member  288 , which causes camming member  288  to cam into recess  249  of distal drive member  248 . In this manner, distal drive member  248  is prevented from distal and/or proximal movement. When lock button  282  is moved from the proximal position to the distal position, the distal end of actuation bar moves distally into the lock out (not shown), against the bias of a biasing member (not shown), to force camming member  288  out of recess  249 , thereby allowing unimpeded axial translation and radial movement of distal drive member  248 . 
     Returning again to  FIG. 6 , adapter  200  includes an electrical assembly  290  supported on and in outer knob housing  202  and inner housing assembly  204 . Electrical assembly  290  includes a plurality of electrical contact blades  292 , supported on a circuit board  294 , for electrical connection to pass-through connector of plate assembly of shell housing  10  of surgical instrument  100 . Electrical assembly  290  serves to allow for calibration and communication information (i.e., life-cycle information, system information, force information) to pass to the circuit board of surgical instrument  100  via an electrical receptacle portion of the power-pack core assembly  106  of surgical instrument  100 . Electrical assembly  290  further includes a strain gauge  296  that is electrically connected to circuit board  294 . Strain gauge  296  is mounted within the inner housing assembly  204  to restrict rotation of the strain gauge  296  relative thereto. First rotatable proximal drive shaft  212  extends through strain gauge  296  to enable the strain gauge  296  to provide a closed-loop feedback to a firing/clamping load exhibited by first rotatable proximal drive shaft  212 . Electrical assembly  290  also includes a slip ring  298  that is non-rotatably and slidably disposed along drive coupling nut  244  of outer tube  206 . Slip ring  298  is in electrical connection with circuit board  294  and serves to permit rotation of first rotatable proximal drive shaft  212  and axial translation of drive coupling nut  244  while still maintaining electrical contact of slip ring  298  with at least another electrical component within adapter  200 , and while permitting the other electrical components to rotate about first rotatable proximal drive shaft  212  and drive coupling nut  244 . 
     Still referring to  FIG. 6 , inner housing assembly  204  includes a hub  205  that has a distally oriented annular wall  207  that defines a substantially circular outer profile. Hub  205  includes a substantially tear-drop shaped inner recess or bore that is shaped and dimensioned to slidably receive articulation bearing assembly  252  therewithin. Inner housing assembly  204  further includes a ring plate  254  that is secured to a distal face of distally oriented annular wall  207  of hub  204   a . Ring plate  254  defines an aperture  254   a  therethrough that is sized and formed therein so as to be aligned with second proximal drive shaft  214  and to rotatably receive a distal tip thereof. In this manner, the distal tip of the second proximal drive shaft  214  is supported and prevented from moving radially away from a longitudinal rotational axis of second proximal drive shaft  214  as second proximal drive shaft  214  is rotated to axially translate articulation bearing assembly  252 . 
     Turning next to  FIG. 10 , in one example, the end effector  500  may be configured for a single use (“disposable loading unit—DLU”) and be similar to those DLU&#39;s disclosed in U.S. Patent Application Publication No. 2010/0301097, entitled LOADING UNIT HAVING DRIVE ASSEMBLY LOCKING MECHANISM, now U.S. Pat. No. 9,795,384, U.S. Patent Application Publication No. 2012/0217284, entitled LOCKING MECHANISM FOR USE WITH LOADING UNITS, now U.S. Pat. No. 8,292,158, and U.S. Patent Application Publication No. 2015/0374371, entitled ADAPTER ASSEMBLIES FOR INTERCONNECTING SURGICAL LOADING UNITS AND HANDLE ASSEMBLIES, the entire disclosures of each such references being hereby incorporated by reference herein. It is also contemplated that the end effector  500  may be configured for multiple uses (MULU) such as those end effectors disclosed in U.S. Patent Application Publication No. 2017/0095250, entitled MULTI-USE LOADING UNIT, the entire disclosure of which is hereby incorporated by reference herein. 
     The depicted surgical instrument  100  fires staples, but it may be adapted to fire any other suitable fastener such as clips and two-part fasteners. In the illustrated arrangement, the end effector  500  comprises a loading unit  510 . The loading unit  510  comprises a proximal body portion  520  and a tool assembly  600 . Tool assembly  600  includes a pair of jaw members including a first jaw member  610  that comprises an anvil assembly  612  and a second jaw member  700  that comprises a cartridge assembly  701 . One jaw member is pivotal in relation to the other to enable the clamping of tissue between the jaw members. The cartridge assembly  701  is movable in relation to anvil assembly  612  and is movable between an open or unclamped position and a closed or approximated position. However, the anvil assembly  612 , or both the cartridge assembly  701  and the anvil assembly  612 , can be movable. 
     The cartridge assembly  701  has a cartridge body  702  and in some instances a support plate  710  that are attached to a channel  720  by a snap-fit connection, a detent, latch, or by another type of connection. The cartridge assembly  701  includes fasteners or staples  704  that are movably supported in a plurality of laterally spaced staple retention slots  706 , which are configured as openings in a tissue contacting surface  708 . Each slot  706  is configured to receive a fastener or staple therein. Cartridge body  702  also defines a plurality of cam wedge slots which accommodate staple pushers  709  and which are open on the bottom (i.e., away from tissue-contacting surface) to allow an actuation sled  712  to pass longitudinally therethrough. The cartridge assembly  701  is removable from channel  720  after the staples have been fired from cartridge body  702 . Another removable cartridge assembly is capable of being loaded onto channel  720 , such that surgical instrument  100  can be actuated again to fire additional fasteners or staples. Further details concerning the cartridge assembly may be found, for example, in U.S. Patent Application Publication No. 2017/0095250 as well as various other references that have been incorporated by reference herein. 
     Cartridge assembly  701  is pivotal in relation to anvil assembly  612  and is movable between an open or unclamped position and a closed or clamped position for insertion through a cannula of a trocar. Proximal body portion  520  includes at least a drive assembly  540  and an articulation link  560 . In one arrangement, drive assembly  540  includes a flexible drive beam  542  that has a distal end  544  and a proximal engagement section  546 . A proximal end of the engagement section  546  includes diametrically opposed inwardly extending fingers  547  that engage a hollow drive member  548  to fixedly secure drive member  548  to the proximal end of beam  542 . Drive member  548  defines a proximal porthole which receives connection member  247  of drive tube  246  of first drive converting assembly  240  of adapter  200  when the end effector  500  is attached to the distal end of the adapter  200 . 
     End effector  500  further includes a housing assembly  530  that comprises an outer housing  532  and an inner housing  534  that is disposed within outer housing  532 . First and second lugs  536  are each disposed on an outer surface of a proximal end  533  of outer housing  532  and are configured to operably engage the distal end of the adapter  200  as discussed in further detail in WO 2016/057225 A1. 
     With reference to  FIG. 10 , for example, anvil assembly  612  includes an anvil cover  630  and an anvil plate  620 , which includes a plurality of staple forming depressions. Anvil plate  620  is secured to an underside of anvil cover  630 . When tool assembly  600  is in the approximated position, staple forming depressions are positioned in juxtaposed alignment with staple receiving slots of the cartridge assembly  701 . 
     The tool assembly  600  includes a mounting assembly  800  that comprises an upper mounting portion  810  and a lower mounting portion  812 . A mounting tail  632  protrudes proximally from a proximal end  631  of the anvil cover  630 . A centrally-located pivot member  814  extends from each upper and lower mounting portions  810  and  812  through openings  822  that are formed in coupling members  820 . In at least one arrangement, the pivot member  814  of the upper mounting portion  810  also extends through an opening  634  in the mounting tail  632  as well. Coupling members  820  each include an interlocking proximal portion  824  that is configured to be received in corresponding grooves formed in distal ends of the outer housing  532  and inner housing  534 . Proximal body portion  520  of end effector  500  includes articulation link  560  that has a hooked proximal end  562 . The articulation link  560  is dimensioned to be slidably positioned within a slot in the inner housing. A pair of H-block assemblies  830  are positioned adjacent the distal end of the outer housing  532  and adjacent the distal end  544  of axial drive assembly  540  to prevent outward buckling and bulging of the flexible drive beam  542  during articulation and firing of surgical stapling apparatus  10 . Each H-block assembly  830  includes a flexible body  832  which includes a proximal end fixedly secured to the distal end of the outer housing  532  and a distal end that is fixedly secured to mounting assembly  800 . In one arrangement, a distal end  564  of the articulation link is pivotally pinned to the right H block assembly  830 . Axial movement of the articulation link  560  will cause the tool assembly to articulate relative to the body portion  520 . 
       FIGS. 11-15  illustrate an adapter  200 ′ that is substantially identical to adapter  200  described above, except for the differences noted below. As can be seen in  FIG. 11 , the adapter  200 ′ includes an outer tube  206  that has a proximal end portion  910  that has a first diameter “FD” and is mounted within the outer knob housing  202 . The proximal end portion  910  may be coupled to the inner housing assembly  204  or otherwise supported therein in the manners discussed in further detail in WO 2016/057225 A1 for example. The proximal end portion  910  extends proximally from a central tube portion  912  that has a second diameter “SD”. In the illustrated embodiment, an end effector  500  is coupled to a distal end  914  of a shaft assembly  203  or outer tube  206 . The outer tube  206  defines a longitudinal axis LA that extends between the proximal end portion  910  and the distal end  914  as can be seen in  FIG. 11 . As can be seen in  FIGS. 10 and 11 , an outer sleeve  570  of the proximal body portion  520  of the end effector  500  has a distal end portion  572  and a proximal end portion  574 . The proximal end portion  574  has a diameter SD′ that is approximately equal to the second diameter SD of the central tube portion  912 . The distal end portion  572  has a third diameter “TD”. In one arrangement, FD and TD are approximately equal and greater than SD. Other arrangements are contemplated wherein FD and TD are not equal, but each are greater than SD. However, it is preferable that for most cases FD and TD are dimensioned for endoscopic insertion through a typical trocar port, cannula or the like. In at least one arrangement ( FIG. 11 ), the outer sleeve  570  is formed with a flat or scalloped side  576  to facilitate improved access within the patient while effectively accommodating the various drive and articulation components of the adapter  200 ′. In addition, by providing the central tube portion  912  with a reduced diameter may afford the adapter  200 ′ with improved thoracic in-between rib access. 
     In at least one arrangement, channel  720 , which may be machined or made of sheet metal, includes a pair of proximal holes  722  ( FIG. 10 ) that are configured to align with a pair of corresponding holes  636  in the anvil cover  630  to receive corresponding pins or bosses  638  ( FIG. 12 ) to facilitate a pivotal relationship between anvil assembly  612  and cartridge assembly  701 . In the illustrated example, a dynamic clamping assembly  550  is attached to or formed at the distal end  544  of the flexible drive beam  542 . The dynamic clamping assembly  550  includes a vertical body portion  552  that has a tissue cutting surface  554  formed thereon or attached thereto. See  FIG. 10 , for example. An anvil engagement feature  556  is formed on one end of the body portion  552  and comprises an anvil engagement tab  557  that protrudes from each lateral side of the body portion  552 . Similarly, a channel engagement feature  558  is formed on the other end of the of the body portion  552  and comprises a channel engagement tab  559  that protrudes from each lateral side of the body portion  552 . See  FIG. 15 . 
     As indicated above, the anvil assembly  612  includes an anvil plate  620 . The anvil plate  620  includes an elongate slot  622  that is configured to accommodate the body portion  552  of the dynamic clamping assembly  550  as the dynamic clamping assembly  550  is axially advanced during the firing process. The elongate slot  622  is defined between two anvil plate ledges  624  that extend along each lateral side of the elongate slot  622 . See  FIG. 10 . As the dynamic clamping assembly  550  is distally advanced, the anvil engagement tabs  557  slidably engage the anvil plate ledges  624  to retain the anvil assembly  612  clamped onto the target tissue. Similarly, during the firing operation, the body portion  552  of the dynamic clamping assembly  550  extends through a central slot in the channel  720  and the channel engagement tabs  559  slidably engage channel ledges  725  extending along each side of the central channel slot to retain the cartridge assembly  701  clamped onto the target tissue. 
     Turning to  FIGS. 13 and 15 , the channel  720  defines a docking area generally designated as  730  that is configured to accommodate the dynamic clamping assembly  550  when it is in its proximal most position referred to herein as an unfired or starting position. In particular, the docking area  730  is partially defined by planar docking surfaces  732  that provides clearance between the channel engagement tabs  559  on the dynamic clamping assembly  550  to enable the cartridge assembly  701  to pivot to a fully opened position. A ramped or camming surface  726  extends from a distal end of each of the docking surfaces  732 . Ramped surface  726  is engaged by the dynamic clamping assembly  550  in order to move the anvil assembly  612  and the cartridge assembly  701  with respect to one another. Similar camming surface could be provided on the anvil assembly  612  in other embodiments. It is envisioned that ramped surfaces  726  may also facilitate the alignment and/or engagement between channel  720  and support plate  620  and/or cartridge body  702 . As the drive assembly  540  is distally advanced (fired), the channel engagement tabs  559  on the dynamic clamping assembly  550  engage the corresponding ramped surfaces  726  to apply a closing motion to the cartridge assembly  701  thus closing the cartridge assembly  701  and the anvil assembly  612 . Further distal translation of the dynamic clamping assembly  550  causes the actuation sled  712  to move distally through cartridge body  702 , which causes cam wedges  713  of actuation sled  712  to sequentially engage staple pushers  709  to move staple pushers  709  vertically within staple retention slots  706  and eject staples  704  into staple forming depressions of anvil plate  620 . Subsequent to the ejection of staples  704  from retention slots  706  (and into tissue), the cutting edge  554  of the dynamic clamping assembly  550  severs the stapled tissue as the tissue cutting edge  554  on the vertical body portion  552  of the dynamic clamping assembly  550  travels distally through a central slot  703  of cartridge body  702 . After staples  704  have been ejected from cartridge body  702  and a user wishes to use the same instrument  10  to fire additional staples  704  (or another type of fastener or knife), the user can remove the loading unit  510  from the adapter  200 ′ and replace it with another fresh or unspent loading unit. In an alternative arrangement, the user may simply remove the spent cartridge body  702  and replace it with a fresh unspent or unfired cartridge body  702 . 
     During use of conventional adapters, debris and body fluids can migrate into the outer tube of the adapter and detrimentally hamper the operation of the adapter articulation and firing drive systems. In egregious cases, such debris and fluids infiltrate into the inner housing assembly of the adapter which may cause the electrical components supported therein to short out and malfunction. Further, due to limited access to the interior of the outer tube of the adapter, such debris and fluids are difficult to remove therefrom which can prevent or reduce the ability to reuse the adapter. 
     Turning to  FIGS. 16 and 17 , in one arrangement, at least one first seal  230  is provided between the proximal inner housing assembly  204  and the first rotatable proximal drive shaft  212  to prevent fluid/debris infiltration within and proximal to the proximal inner housing assembly  204 . In addition, at least one second seal  232  is provided between the articulation bar  258  and the outer tube  206  to prevent fluid/debris from passing therebetween to enter the proximal inner housing assembly  204 . At least one third housing seal  233  may be provided around a hub  205  of the proximal inner housing  204  to establish a seal between the hub  205  and the outer knob housing  202 . The first, second, and third seals  230 ,  232 ,  233  may comprise, for example, flexible O-rings manufactured from rubber or other suitable material. 
     In other arrangements, it may be desirable for the first and second seals  230 ,  232  to be located in the adapter  200  distal to the electronic components housed within the outer knob housing  202 . For example, to prevent fluids/debris from fouling/shorting the slip ring assembly  298 , it is desirable establish seals between the various moving components of the adapter  200  that are operably supported within the outer tube  206  in a location or locations that are each distal to the slip ring assembly  298 , for example. The seals  230 ,  232  may be supported in the wall of the outer tube and/or in mounting member  234  or other separate mounting member/bushing/housing supported within the outer tube  206  and configured to facilitate axial movement of the distal drive member  248  as well as the articulation bar  258  while establishing a fluid-tight seal between the bushing and/or outer tube and the distal drive member  248  and the articulation bar  258 . See  FIGS. 18 and 20 . In the embodiment illustrated in  FIG. 19  for example, the first seal  230  may additionally have wiper features  231  that also slidably engage the distal drive member  248  to prevent fluid/debris D from infiltrating in the proximal direction PD into the proximal inner housing assembly  204 . In at least one arrangement to enable debris and fluids that have collected in the outer tube  206  distal to the first and second seals  230 ,  232 , at least two flushing ports  236 ,  238  are provided within the outer tube  206 . See e.g.,  FIGS. 18 and 20 . The axially spaced flushing ports  236 ,  238  are located distal to the first and second seals  230 ,  232 . A flushing solution (e.g., cleaning fluid, saline fluid, air, etc.) may be entered into one or more port(s) to force the errant debris and fluid out of one or more other port(s). 
     As discussed above, in one example, the surgical end effector  500  comprises a loading unit  510  that is configured to be operably coupled to a distal end of a shaft assembly of an adapter. As can be seen in  FIGS. 22-24 , in one arrangement the loading unit  510  comprises a proximal body portion  520  and a tool assembly  600  that is configured to be articulated relative to the proximal body portion  520 . When the proximal body portion  520  is coupled to the shaft assembly, the proximal body portion  520  is axially aligned with a longitudinal axis LA that is defined by the shaft assembly of the adapter. When the tool assembly  600  is in an unarticulated position ( FIG. 22 ), an axis TA of the tool assembly  600  is aligned with the longitudinal axis LA of the adapter shaft assembly, for example. The tool assembly  600  may also be articulated to a first side ( FIG. 23 ) wherein the tool axis TA is transverse to the longitudinal axis LA as well as to a second side ( FIG. 24 ) wherein the tool axis TA is transverse to the longitudinal axis LA. During some articulation motions, an articulation bar  258  of the adapter may encounter significant resistive forces. Sensing the resisting forces on the articulation frame or articulation bar  258  which is interconnected to an articulation link  560  of the DLU or MLU via a strain gauge or other deflection oriented circuit would enable the control circuit for the articulation motor to back drive the articulation motor when the force exceeds a predetermined threshold. Such action would remove some or all of the resistance provided to the articulation frame via the drive member of the adapter and thereby prevent internal drive damage and/or minimize collateral tissue damage.  FIG. 26  illustrates use of multi-axis strain gauges  310 ,  312  on the outer tube assembly  206 . The multi-axis strain gauges  310 ,  312  are connected to the circuit board  294  located within the inner housing assembly  204  (shown in  FIG. 6 ). The strain gauges may, in the alternative, be mounted on the articulation bar  258 . In at least one arrangement, for example, the strain goes negative as the force on the articulation bar  258  increases. Such arrangement may be particularly useful when the user intended to straighten the tool assembly ( FIG. 22 ) to pull it back through a trocar, but failed to get the tool assembly  600  fully straightened. In such case, the end effector may become jammed within the trocar cannula and/or result in high loading of the articulation frame or articulation bar  258  and drive shaft  214 . This condition might be completely mitigated if the articulation system could sense this condition via load on the articulation bar  258  or drive screw  214  and longitudinally adjust the position of the articulation bar  258  by energizing the articulation motor of the surgical instrument  100  to which the adapter is attached until the bending forces are below the predetermined threshold. 
     Articulation of the end effector  500  or, more particularly, the articulation of the tool assembly  600  of the end effector  500  is controlled by rotating the second proximal drive shaft  214  that is in threaded engagement with the articulation bearing assembly  252  as was discussed above. See  FIGS. 6-9 . The second drive converting assembly  250  of adapter  200  further includes articulation bar  258  that has a proximal portion that is secured to inner race  257  of articulation bearing  255 . See  FIG. 7 . A distal portion of articulation bar  258  includes a slot  258   a  therein, which is configured to accept a hook  562  of the articulation link  560  ( FIG. 10 ) of end effector  500 . Articulation bar  258  functions as a force transmitting member to components of end effector  500 . In the illustrated arrangement and as further discussed in WO 2016/057225 A1, articulation bearing assembly  252  is both rotatable and longitudinally translatable and is configured to permit free, unimpeded rotational movement of the tool assembly  600  of the end effector  500  when its jaw members  610 ,  700  are in an approximated position and/or when jaw members  610 ,  700  are articulated. 
     In operation, as second proximal drive shaft  214  is rotated due to a rotation of second connector sleeve  222 , as a result of the rotation of the second coupling shaft  64   c  of surgical instrument  100 , articulation bearing assembly  252  is translated axially along threaded distal end portion  214   a  of second proximal drive shaft  214 . This axial translation of the articulation bearing assembly  252  causes the articulation bar  258  to be axially translated relative to outer tube  206 . As articulation bar  258  is translated axially, it causes concomitant axial translation of articulation link  560  of end effector  500  to effectuate an articulation of tool assembly  600 . Articulation bar  258  is secured to inner race  257  of articulation bearing  253  and is thus free to rotate about the longitudinal axis relative to outer race  259  of articulation bearing  253 . 
     It may be desirable to control the articulation of the end effector and to monitor the articulated position thereof during a surgical procedure.  FIGS. 27-29  illustrate an improved articulation control system or second drive converting assembly  3250 . The second drive converting assembly  3250  in many aspects is identical to the second drive converting assembly  250  described above, except for the specific differences discussed below. As can be seen in  FIG. 27 , the second drive converting assembly  3250  includes second proximal drive shaft  3214  that is rotatably supported within inner housing assembly  204  (shown in  FIG. 6 ). Second rotatable proximal drive shaft  3214  includes a non-circular or shaped proximal end portion  3215  that is configured for connection with second coupling shaft  64   c  of surgical instrument  100 . Second rotatable proximal drive shaft  3214  further includes a threaded distal end portion  3214   a  that is configured to threadably engage an articulation bearing housing  3253  of an articulation bearing assembly  3252 . Housing  3253  supports an articulation bearing  255  that has an inner race  257  that is independently rotatable relative to an outer race  259 . Articulation bearing housing  3253  has a non-circular outer profile, for example tear-dropped shaped, that is slidably and non-rotatably disposed within a complementary bore (not shown) of inner housing hub  204   a  ( FIG. 6 ). Second drive converting assembly  3250  further includes articulation bar  3258  that has a proximal portion that is secured to inner race  257  of articulation bearing  255 . A distal portion of articulation bar  3258  includes a slot  3258   a  therein, which is configured to accept a hook  562  of the articulation link  560  ( FIG. 10 ) of end effector  500 . Articulation bar  3258  functions as a force transmitting member to components of end effector  500 . 
     In the illustrated arrangement, the articulation bearing housing  3253  is in threaded engagement with the threaded distal end portion  3214   a  of the second rotatable proximal drive shaft  3214 . The bearing housing  3253  may also be referred to herein as an articulation driver arrangement. In at least one example, the bearing housing or articulation driver arrangement  3252  is configured to move axially in two directions from a central or neutral position ( FIG. 27 ) to a proximal axial position ( FIG. 28 ) and to a distal axial position ( FIG. 29 ). When the bearing housing  3253  is in the central or neutral position, the tool assembly  600  is axially aligned with the proximal body portion  520  such that the tool assembly axis TA is aligned with the longitudinal axis LA ( FIG. 22 ). Stated another way, the tool assembly or surgical end effector is unarticulated. The tool assembly  600  is oriented in the unarticulated position initially to facilitate insertion of the end effector through a trocar cannula. When the second rotatable proximal drive shaft  3214  is rotated in a first rotary direction, the bearing housing  3252  is driven in a proximal axial direction from the neutral position. As the bearing housing  3252  moves in the proximal direction PD, the tool assembly  600  articulates in a first articulation direction AD 1  until the bearing housing  3252  reaches the proximal axial position ( FIG. 28 ) at which point the tool assembly  600  is fully articulated in the articulation direction AD 1  shown in  FIG. 23 , for example. When the second rotatable proximal drive shaft  3214  is rotated in a second rotary direction (opposite the first rotary direction), the bearing housing  3253  is driven in a distal direction DD from the neutral position. As the bearing housing  3253  moves in the distal direction DD, the tool assembly  600  articulates in a second articulation direction AD 2  until the bearing housing  3253  reaches the distal axial position ( FIG. 29 ) at which point the tool assembly  600  is fully articulated in the articulation direction AD 2  shown in  FIG. 24 , for example. 
     As discussed above, to insert the surgical end effector into the patient through a cannula of a trocar, the tool assembly may need to be in the unarticulated position and it may need to be returned to the unarticulated position to enable the surgical end effector to be removed from the patient through the trocar cannula after the procedure is completed. Thus, the articulation control system may need to be able to precisely control the axial position of the bearing housing to ensure that the tool assembly is precisely aligned with the proximal housing to avoid possible jamming of the end effector with the trocar cannula. In one example, an articulation sensor assembly, generally indicated as  3300  is employed to communicate with a motor controller circuit board  142   a  ( FIG. 4 ), or other controller arrangement of the electromechanical surgical instrument  100  to which the adapter is operably coupled. In the illustrated example, the articulation sensor assembly  3300  comprises a proximal sensor  3310  and a distal sensor  3320  that are mounted to a sensor bracket  3302 . In addition, the bearing housing  3253  includes a sensor magnet  3330  as can be seen in  FIG. 27 . The proximal and distal sensors  3310 ,  3320  may comprise conventional Hall sensors and be wired to the adapter circuit board  294  ( FIG. 6 ) for ultimate electrical communication with the motor controller circuit board  142   a  in the electromechanical surgical instrument  100  ( FIG. 4 ). The sensors  3310 ,  3320  serve to detect the position of the sensor magnet  3330  so as to monitor when the bearing housing  3253  nears the neutral position and reaches the neutral position and convey that information back to the motor controller circuit board. Such arrangement enables a motor controller algorithm to vary the speed of the articulation motor as it approaches the neutral position to allow the user to stop near the neutral position without the system intentionally pausing at that predetermined position. 
     In addition to the above described articulation sensor assembly, an O-ring  3340  or similar feature is located on the threaded portion  3214   a  of the second rotatable proximal drive shaft  3214  in place of or over some of the threads of the threaded portion  3214   a . In such an arrangement, a spike in the articulation motor current (e.g., motor  156 — FIG. 4 ) will occur when the O-ring  3340  encounters a threaded portion  3350  of the bearing housing  3253 . This current spike will occur when the O-ring  3340  encounters the threads  3350  to increase rotary resistance or friction when entering from a proximal direction or a distal direction of travel and is used to determine the distance that the bearing housing  3253  is from the neutral position. Once a spike in motor current is detected, an algorithm controlling the articulation motor  156  sets the drive screw rotary position to zero and the articulation motor  156  then rotates the drive screw  3214  in the proper rotary direction to drive the bearing housing  3253  axially to reach the neutral position. In alternative arrangements of the O-ring, select threads of the threaded portion  3214   a  may be removed or omitted or intentionally damaged or altered to alter the rotational resistance/friction and thus alter the amount of motor current drawn by the articulation motor to facilitate control of the articulation motor in the above-described manner. 
       FIGS. 30 and 31  depict an alternative proximal drive shaft  3414  that may be employed to axially advance the bearing housing  3253  and detect the position of the bearing housing  3253  as the drive shaft  3414  is rotated in the first and second rotary directions. As can be seen in  FIGS. 30 and 31 , the proximal drive shaft  3414  is formed with a proximal set of threads  3420 , a distal set of threads  3430  and a center thread  3440 . The center thread  3440  is centrally located between the proximal set of threads  3420  and the distal set of threads  3430  and is separated therefrom by unthreaded portions  3450 . Threads  3420 ,  3430 ,  3440  are configured to threadably engage internal threads  3350  formed in the bearing housing  3253 .  FIG. 30  illustrates the bearing housing  3253  in the neutral position. As can be seen in  FIG. 30 , the least mount of threads (including the threads of the proximal thread segment  3420 , the distal thread segment  3430  and the center thread  3430 ) are in threaded contact with the threads  3350  of the bearing housing  3253  and will thus result in the lowest amount of current drawn by the articulation motor.  FIG. 31  illustrates the bearing housing  3253  being moved in the proximal direction with all of the threads of the proximal thread segment  3420  in threaded engagement with the threads in the bearing housing  3253  which will cause the articulation motor  156  to experience a higher amount of current. Such higher current will also be experienced when the bearing housing  3253  is driven in the distal direction DD. By monitoring when the current is at its lowest magnitude or is approaching the lowest magnitude, an algorithm controlling the articulation motor  156  may be used to slow down and stop the articulation motor  156  in the various manners described herein. 
       FIGS. 32 and 33  depict an alternative proximal drive shaft  3514  and switch arrangement  3550  that may be employed to detect when the bearing housing  3253  approaches and reaches the neutral position as the drive shaft  3514  is rotated in the first and second rotary directions. As can be seen in  FIGS. 32 and 33 , the proximal drive shaft  3514  is formed with a proximal set of threads  3520  and a distal set of threads  3530  that are separated by an unthreaded central portion  3540  that has a diameter that decreases or tapers from each end so that it is smallest in its center. Threads  3520 ,  3530  are configured to threadably engage internal threads  3350  formed in the bearing housing  3253 . In this arrangement, the switch arrangement  3550  comprises a radially movable switch plunger  3552  that is supported in the bearing housing  3253  and is biased into contact the drive shaft  3514  by a biasing member such as a spring  3554 . The switch plunger  3552  includes contacts  3556  that are configured to operably interface with contacts  3558  in the bearing housing  3253 .  FIG. 32  illustrates the bearing housing  3253  in the neutral position. As can be seen in that  FIG. 32 , the switch plunger  3552  is in contact with approximately the center of the unthreaded central portion  3540  of the drive shaft  3514  such that the contacts  3556  are in contact with the contacts  3558 . Contacts  3556 / 3558  communicate with the motor control circuit in the surgical instrument  100  through the circuit board  294  to indicate that the bearing housing  3253  is in the neutral position.  FIG. 33  illustrates the bearing housing  3253  being moved in the proximal direction PD with all of the threads of the proximal thread segment  3520  in threaded engagement with the threads in the bearing housing  3253  and the switch plunger  3552  in contact with the proximal thread segment  3520  which moves the contacts  3556  away from contacts  3558  as shown. This condition will also occur when the bearing housing  3253  is moved in the distal direction. Such arrangements may be employed to control the articulation motor in the above-described manners. 
       FIGS. 34-37  depict an alternative switch arrangement  3650  for detecting when the bearing housing  3553  is in the neutral position. In this arrangement for example, the switch arrangement  3650  is supported in the inner housing  204  and includes a radially movable switch plunger  3652 . As can be seen in  FIGS. 34-37 , the bearing housing  3553  is formed with an activator detent  3555  that is configured to interact with the switch plunger  3652 . The switch plunger  3652  interacts with a leaf spring  3654  that is configured to engage a contact  3658  in the inner housing  204 .  FIG. 35  illustrates the bearing housing  3553  in a neutral position. When in that position, the switch plunger  3652  has biased the leaf spring  3654  into contact with the contact  3658  to complete a circuit to inform the motor controller circuit through the circuit board  294  that the bearing housing  3553  is in the neutral position.  FIG. 36  illustrates the bearing housing  3553  in a position that is proximal to the neutral position such that the detent  3555  on the bearing housing  3553  is proximal to the center of the switch plunger  3652  to enable the spring  3654  to move out of contact with the contact  3658 .  FIG. 37  illustrates the bearing housing  3553  in a position distal to the neutral position such that the detent  3555  on the bearing housing  3553  is distal to the center of the switch plunger  3652  to enable the leaf spring  3654  to move out of contact with the contact  3658 . Such arrangements may be employed to control the articulation motor  158  in the above-described manners. 
     As described above, in at least some examples, the adapter  200  employs a proximal rotary drive shaft  216  that is ultimately rotated by a corresponding motor in the surgical instrument  100  to rotate the shaft assembly about the longitudinal axis LA. During a procedure, it may be desirable for the clinician to know the exact rotary position of the shaft assembly for adjustment purposes and resetting purposes. One arrangement, for example, could employ an optical detector arrangement for detecting incremental etched or printed markings on the outer shaft tube  206 , for example. Such markings may be provided completely around a proximal end portion of the outer tube  206  that allow for detection and indication of multiple 360 increments. Longitudinal marks may correlate with a ring advancing feature that moves one increment distal for each full 360° rotation. 
       FIG. 38  illustrates another rotational detection system  3750  that may be employed to detect and control the rotation of the shaft assembly about the longitudinal axis LA. As can be seen in that Figure, the rotational detection system  3750  includes a pair of rotational sensors  3752 ,  3754  that are configured to sense the position of a sensor magnet  3756  in one of the opposed, radially extending protrusions  266   b . The sensors  3752 ,  3754  are below the centerline of the adapter. In another arrangement, one rotational sensor is employed and a sensor magnet is mounted in each of the protrusions  266   b . The magnets are oriented so their polarities are different. Due to the different polarities, a single sensor is able to detect the positions of both magnets ensuring unique tracking of each magnet and proper determination of position. This information is transmitted to the motor controller circuit in the surgical instrument  100  through circuit board  294  and contacts  292 . A control algorithm may be employed to control the second motor  154  such that the rotation of the shaft assembly may be limited to rotate through a certain range or stop at a certain point or to bring the rotations induced within the last use back to a zero position. In other examples, multiple 360° rotation overall limiting features which allow the shaft to turn a predetermined number of 360° rotations before instructing the user to counter rotate. In other arrangements, the system may automatically cause the motor to counter rotate the shaft assembly after the first closure cycle after the cartridge is reloaded or the DLU is replaced. 
     EXAMPLES 
     Example 1 
     An adapter for use with an electromechanical surgical instrument. In at least one example, the adapter comprises an adapter housing assembly that is configured to be operably coupled to the electromechanical surgical instrument. A shaft assembly defines a longitudinal axis that extends between a proximal end and a distal end thereof. The proximal end is operably coupled to the adapter housing assembly. A surgical end effector is operably coupled to the distal end of the shaft assembly for selective articulation relative to the shaft assembly. The adapter further comprises an articulation control system that includes a rotary drive shaft that is configured to operably interface with a source of rotary drive motions in the electromechanical surgical instrument when the adapter housing assembly is operably coupled thereto. An articulation driver arrangement operably interfaces with the rotary drive shaft and the surgical end effector. The articulation driver arrangement comprises an articulation member that is configured to move axially in response to rotation of the rotary drive shaft to articulate the surgical end effector through a range of articulated orientations. The articulation control system further comprises means for monitoring an axial position of the articulation member during rotation of the rotary drive member. The means is also configured to communicate a signal corresponding to the axial position of the articulation member to the electromechanical surgical instrument when the adapter housing assembly is operably coupled thereto. 
     Example 2 
     The adapter of Example 1, wherein the articulation member is configured to move axially between a beginning axial position and an ending axial position in response to rotation of the rotary drive shaft. The means for monitoring is configured to monitor the axial position of the articulation member between the beginning axial position and the ending axial position. 
     Example 3 
     The adapter of Example 2, wherein the means for monitoring comprises an articulation sensor assembly that is configured to communicate with the electromechanical surgical instrument when the adapter housing assembly is operably coupled thereto. In at least one example, the articulation sensor assembly comprises a first articulation sensor that corresponds to the beginning axial position and a second articulation sensor that corresponds to the ending axial position. The first and second articulation sensors are configured to detect the axial position of the articulation member between the beginning axial position and the ending axial position and generate the signal that corresponds to the axial position of the articulation member and communicate the signal to the electromechanical surgical instrument. 
     Example 4 
     The adapter of Example 3, wherein a portion of the articulation member is operably supported in an axially movable articulation bearing housing that is in threaded engagement with the rotary drive shaft and is configured to move between the beginning axial position and the ending axial position in response to rotation of the rotary drive shaft. The first and second articulation sensors are configured to sense a position of an articulation magnet that is supported by the articulation bearing housing. 
     Example 5 
     The adapter of Examples 2, 3 or 4, wherein when a portion of the articulation member is in a neutral axial position located between the beginning axial position and the ending axial position, the surgical end effector is axially aligned with the longitudinal axis in an unarticulated position. 
     Example 6 
     The adapter of Example 5, further comprising means for determining when the portion of the articulation member is in the neutral axial position. 
     Example 7 
     The adapter of Example 6, wherein the portion of the articulation member is operably supported in an axially movable articulation bearing housing that is in threaded engagement with the rotary drive shaft and is configured to move between the beginning axial position and the ending axial position in response to rotation of the rotary drive shaft. The means for determining when the portion of the articulation member is in the neutral axial position comprises a neutral switch member that is configured to detect the bearing housing when the bearing housing is in the neutral axial position and send a corresponding signal to the electromechanical instrument. 
     Example 8 
     The adapter of Examples 6 or 7, wherein the source of rotary drive motions comprises an electrical powered articulation motor in the electromechanical surgical instrument. The rotary drive shaft is configured to operably interface with an output shaft of the electrically powered articulation motor such that operation of the electrical powered articulation motor at a an electrical current level is sufficient to move the portion of the articulation member between the beginning axial position and the ending axial position. The means for determining when the portion of the articulation member is in the neutral axial position comprises means for altering the level of electrical current when the portion of the articulation member is in the neutral position. 
     Example 9 
     The adapter of Example 8, wherein the portion of the articulation member is operably supported in an axially movable articulation bearing housing that is in threaded engagement with a threaded portion of the rotary drive shaft and is configured to move between the beginning axial position and the ending axial position in response to rotation of the rotary drive shaft. The means for altering the level of electrical current when the portion of the articulation member is in the neutral position comprises a rotational resistance generator on the rotary drive shaft that is configured to increase rotational resistance between the rotary drive shaft and the articulation bearing housing when the articulation bearing housing is in the neutral position to thereby increase the level of electrical current drawn by the electrical powered articulation motor. 
     Example 10 
     The adapter of Example 9, wherein the rotational resistance generator comprises an O-ring on the threaded portion of the rotary drive shaft. 
     Example 11 
     The adapter of Example 6, wherein the portion of the articulation member is operably supported in an axially movable articulation bearing housing that is in threaded engagement with the rotary drive shaft and is configured to move between the beginning axial position and the ending axial position in response to rotation of the rotary drive shaft. The source of rotary drive motions comprises an electrical powered articulation motor in the electromechanical surgical instrument. The rotary drive shaft is configured to operably interface with an output shaft of the electrically powered articulation motor such that when the electrical powered articulation motor draws a level of electrical current, the articulation motor causes the rotary drive shaft to move said portion of said articulation member between the beginning axial position and the ending axial position. The means for determining when the portion of the articulation member is in the neutral axial position comprises a thread arrangement on the rotary drive shaft that is configured to reduce the level of electrical current drawn by the electrically powered articulation motor when the bearing housing is in the neutral axial position. 
     Example 12 
     The adapter of Example 11, wherein the thread arrangement comprises a plurality of threads in threaded engagement with the bearing housing for moving the bearing housing between said beginning and ending axial positions. The plurality of threads are configured such that a lesser number of threads are in threaded engagement with the bearing housing when the bearing housing is in the neutral position so as to reduce the level of electrical current drawn by the electrically powered articulation motor. 
     Example 13 
     The adapter of Example 6, wherein the portion of the articulation member is operably supported in an axially movable articulation housing that is in threaded engagement with a thread arrangement of the rotary drive shaft and is configured to move between the beginning axial position and the ending axial position in response to rotation of the rotary drive shaft. The thread arrangement comprises a first thread segment that is configured to threadably engage the articulation housing and a second thread segment that is spaced from the first thread segment by a central segment that has a configuration that differs from the first and second thread segments. The means for determining when the portion of the articulation member is in the neutral axial position comprises a sensor assembly that is configured to interact with the central segment and generate a signal that is indicative of an axial position of the movable articulation housing. 
     Example 14 
     The adapter of Example 13, wherein the central segment is not threaded. 
     Example 15 
     The adapter of Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 or 14, wherein the adapter housing assembly comprises a drive coupler portion that is configured to be operably coupled to the electromechanical surgical instrument. An outer knob housing is coupled to the shaft assembly and is rotatably supported on the drive coupler portion for selective rotation relative thereto about the longitudinal axis. The adapter further comprises a rotary drive system that is configured to operably interface with another source of rotary drive motions in the electromechanical surgical instrument when the drive coupler portion is operably coupled thereto. The rotary drive system is configured to selectively rotate the outer knob housing about the longitudinal axis. The adapter further comprises means for monitoring a rotary position of the outer knob housing during operation of the rotary drive system and communicating another signal corresponding to the rotary position of the outer knob housing to the electromechanical surgical instrument when the drive coupler portion is operably coupled thereto. 
     Example 16 
     The adapter of Example 15, wherein the rotary drive system comprises another rotary drive shaft arrangement that is configured to operably interface with another source of rotary drive motions in the electromechanical surgical instrument. The other rotary drive shaft arrangement is in meshing engagement with the outer knob housing such that rotation of the other rotary drive shaft rotates the outer knob housing. The means for monitoring a rotary position of the outer knob housing comprises a sensor arrangement that is configured to detect at least one magnet that is supported by the outer knob housing. 
     Example 17 
     An adapter for use with an electromechanical surgical instrument. In at least one example, the adapter comprises a shaft assembly that defines a longitudinal axis that extends between a proximal end and a distal end thereof. A surgical end effector is operably coupled to the distal end of the shaft assembly. The adapter further comprises an adapter housing assembly that includes a drive coupler portion that is configured to be operably coupled to the electromechanical surgical instrument. An outer knob housing is coupled to the shaft assembly and is rotatably supported on the drive coupler portion for selective rotation relative thereto about the longitudinal axis. The adapter further comprises a rotary drive system that is configured to operably interface with a source of rotary drive motions in the electromechanical surgical instrument when the drive coupler portion is operably coupled thereto. The rotary drive system is configured to selectively rotate the outer knob housing about the longitudinal axis. The adapter also comprises means for monitoring a rotary position of the outer knob housing about the longitudinal axis during operation of the rotary drive system and communicating a signal corresponding to the rotary position to the electromechanical surgical instrument. 
     Example 18 
     The adapter of Example 17, wherein the rotary drive system comprises a rotary drive shaft arrangement that is configured to operably interface with the source of rotary drive motions in the electromechanical surgical instrument. The rotary drive shaft arrangement is in meshing engagement with the outer knob housing such that rotation of the rotary drive shaft rotates the outer knob housing. The means for monitoring a rotary position of the outer knob housing comprises a sensor arrangement that is configured to detect at least one magnet that is supported by the outer knob housing. 
     Example 19 
     An adapter for use with an electromechanical surgical instrument. In at least one example, the adapter comprises an adapter housing assembly that is configured to be operably coupled to the electromechanical surgical instrument. A shaft assembly defines a longitudinal axis that extends between a proximal end and a distal end thereof. The proximal end is operably coupled to the adapter housing assembly. A surgical loading unit is operably coupled to the distal end of the shaft assembly for selective articulation relative to the shaft assembly. The surgical loading unit comprises a staple cartridge assembly and an anvil assembly. A dynamic clamping assembly is axially movable in the surgical loading unit in response to a firing drive motion applied thereto to clamp the anvil assembly and staple cartridge assembly onto tissue and cut the clamped tissue and fire staples from the staple cartridge assembly. The adapter further comprises a first rotary drive shaft assembly that is configured to operably interface with a first source of rotary drive motions in the electromechanical surgical instrument and the dynamic clamping assembly to apply the firing drive motion thereto. The adapter further comprises an articulation control system that includes a second rotary drive shaft that is configured to operably interface with a second source of rotary drive motions in the electromechanical surgical instrument when the adapter housing assembly is operably coupled thereto. An articulation driver arrangement operably interfaces with the second rotary drive shaft and the surgical loading unit and comprises an articulation member that is configured to move axially in response to rotation of the second rotary drive shaft to articulate the surgical loading unit through a range of articulated orientations. The adapter further comprises means for monitoring an axial position of the articulation member during rotation of the second rotary drive member and communicating a signal corresponding to the axial position to the electromechanical surgical instrument when the adapter housing is operably coupled thereto. 
     Example 20 
     The adapter of Example 19, wherein the adapter housing comprises a drive coupler portion that is configured to be operably coupled to the electromechanical surgical instrument. An outer knob housing is coupled to the shaft assembly and is rotatably supported on the drive coupler portion for selective rotation relative thereto about the longitudinal axis. The adapter further comprises a rotary drive system that is configured to operably interface with a third source of rotary drive motions in the electromechanical surgical instrument when the drive coupler portion is operably coupled thereto and is configured to selectively rotate the outer knob housing about the longitudinal axis. The adapter further comprised means for monitoring a rotary position of the outer knob housing during operation of the rotary drive system and communicating another signal corresponding to the rotary position to the electromechanical surgical instrument when the drive coupler portion is operably coupled thereto. 
     Many of the surgical instrument systems described herein are motivated by an electric motor; however, the surgical instrument systems described herein can be motivated in any suitable manner. In various instances, the surgical instrument systems described herein can be motivated by a manually-operated trigger, for example. In certain instances, the motors disclosed herein may comprise a portion or portions of a robotically controlled system. Moreover, any of the end effectors and/or tool assemblies disclosed herein can be utilized with a robotic surgical instrument system. 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, for example, discloses several examples of a robotic surgical instrument system in greater detail. 
     The surgical instrument systems described herein have been described in connection with the deployment and deformation of staples; however, the embodiments described herein are not so limited. Various embodiments are envisioned which deploy fasteners other than staples, such as clamps or tacks, for example. Moreover, various embodiments are envisioned which utilize any suitable means for sealing tissue. For instance, an end effector in accordance with various embodiments can comprise electrodes configured to heat and seal the tissue. Also, for instance, an end effector in accordance with certain embodiments can apply vibrational energy to seal the tissue. 
     Although various devices have been described herein in connection with certain embodiments, modifications and variations to those embodiments may be implemented. 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 ore more other embodiments without limitation. Also, where materials are disclosed for certain components, other materials may be used. Furthermore, according to various embodiments, a single component may be replaced by multiple components, and multiple components may be replaced by a single component, to perform a given function or functions. The foregoing description and following claims are intended to cover all such modification and variations. 
     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. In either case, however, a device can be reconditioned for reuse after at least one use. Reconditioning can include any combination of the steps including, but not limited to, the disassembly of the device, followed by cleaning or replacement of particular pieces of the device, and subsequent reassembly of the device. In particular, a reconditioning facility and/or surgical team can disassemble a device and, after cleaning and/or replacing particular parts of the device, the device can be reassembled for subsequent use. Those skilled in the art will appreciate that reconditioning of a device can 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. 
     The devices disclosed 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, and/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 radiation, gamma radiation, ethylene oxide, plasma peroxide, and/or steam. 
     While this invention has been described as having exemplary designs, the present invention may be further modified within the spirit and scope of the disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles.