Patent Publication Number: US-11642128-B2

Title: Method for articulating a surgical instrument

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional application claiming priority under 35 U.S.C. § 121 to U.S. patent application Ser. No. 15/635,663, entitled METHOD FOR ARTICULATING A SURGICAL INSTRUMENT, filed Jun. 28, 2017, which issued on Sep. 8, 2020 as U.S. Pat. No. 10,765,427, the entire disclosure of which is hereby incorporated by reference herein. 
    
    
     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 side elevational view of a surgical system comprising a handle assembly and multiple interchangeable surgical tool assemblies that may be used therewith; 
         FIG.  2    is an exploded assembly view of portions of the handle assembly and one of the interchangeable surgical tool assemblies depicted in  FIG.  1   ; 
         FIG.  3    is a perspective view of one of the interchangeable surgical tool assemblies depicted in  FIG.  1   ; 
         FIG.  4    is an exploded assembly view of the interchangeable surgical tool assembly of  FIG.  3   ; 
         FIG.  5    is another exploded assembly view of a distal portion of the interchangeable surgical tool assembly of  FIGS.  3  and  4   ; 
         FIG.  6    is another exploded assembly view of a distal portion of the interchangeable surgical tool assembly of  FIGS.  3 - 5   ; 
         FIG.  7    is an exploded assembly view of a proximal portion of the interchangeable surgical tool assembly of  FIGS.  3 - 6   ; 
         FIG.  8    is another exploded assembly view of a portion of the interchangeable surgical tool assembly of  FIGS.  3 - 7   ; 
         FIG.  9    is another exploded assembly view of a portion of the interchangeable surgical tool assembly of  FIGS.  3 - 8   ; 
         FIG.  10    is a perspective view of a proximal portion of the interchangeable surgical tool assembly of  FIGS.  3 - 9   ; 
         FIG.  11    is another perspective view of the proximal portion of the interchangeable surgical tool assembly of  FIGS.  3 - 10   ; 
         FIG.  12    is a cross-sectional perspective view of the proximal portion of the interchangeable surgical tool assembly of  FIGS.  3 - 11   ; 
         FIG.  13    is another cross-sectional perspective view of the proximal portion of the interchangeable surgical tool assembly of  FIGS.  3 - 12   ; 
         FIG.  14    is another cross-sectional perspective view of the proximal portion of the interchangeable surgical tool assembly of  FIGS.  3 - 13   ; 
         FIG.  15    is a cross-sectional perspective view of a distal portion of the interchangeable surgical tool assembly of  FIGS.  3 - 14   ; 
         FIG.  16    is a perspective view of another one of the interchangeable surgical tool assemblies depicted in  FIG.  1   ; 
         FIG.  17    is an exploded assembly view of a proximal portion of the interchangeable surgical tool assembly of  FIG.  16   ; 
         FIG.  18    is another exploded assembly view of a distal portion of the interchangeable surgical tool assembly of  FIGS.  16  and  17   ; 
         FIG.  19    is a perspective view of another one of the interchangeable surgical tool assemblies depicted in  FIG.  1   ; 
         FIG.  20    is an exploded assembly view of a proximal portion of the interchangeable surgical tool assembly of  FIG.  19   ; 
         FIG.  21    is another exploded assembly view of a distal portion of the interchangeable surgical tool assembly of  FIGS.  19  and  20   ; 
         FIG.  22    is a perspective view of another one of the interchangeable surgical tool assemblies depicted in  FIG.  1   ; 
         FIG.  23    is an exploded assembly view of a proximal portion of the interchangeable surgical tool assembly of  FIG.  22   ; 
         FIG.  24    is another exploded assembly view of a distal portion of the interchangeable surgical tool assembly of  FIGS.  22  and  23   ; 
         FIG.  25    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  3    with the anvil thereof in a fully closed position; 
         FIG.  26    is an enlarged side elevational view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  25   ; 
         FIG.  27    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  16    with the anvil thereof in a fully closed position; 
         FIG.  28    is an enlarged side elevational view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  27   ; 
         FIG.  29    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  19    with the anvil thereof in a fully closed position; 
         FIG.  30    is an enlarged side elevational view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  29   ; 
         FIG.  31    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  22    with the anvil thereof in a fully closed position; 
         FIG.  32    is an enlarged side elevational view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  31   ; 
         FIG.  33    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  3    with the anvil thereof in a fully open position; 
         FIG.  34    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  16    with the anvil thereof in a fully open position; 
         FIG.  35    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  19    with the anvil thereof in a fully open position; 
         FIG.  36    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  22    with the anvil thereof in a fully open position; 
         FIG.  37    is a side elevational view of a distal portion of another interchangeable surgical tool assembly with the anvil thereof shown in one open position in solid lines and another open position in phantom lines; 
         FIG.  38    is a side elevational view of a distal portion of another interchangeable surgical tool assembly with the anvil thereof in an open position; 
         FIG.  39    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  3    with the anvil thereof in a fully open position; 
         FIG.  40    is an enlarged side elevational view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  39   ; 
         FIG.  41    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIGS.  39  and  40    with the anvil thereof in a fully closed position; 
         FIG.  42    is an enlarged side elevational view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  16    with the anvil thereof in a fully open position; 
         FIG.  43    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  42    with the anvil thereof in a fully closed position; 
         FIG.  44    is an enlarged side elevational view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  19    with the anvil thereof in a fully open position; 
         FIG.  45    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  44    with the anvil thereof in a fully closed position; 
         FIG.  46    is an enlarged side elevational view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  22    with the anvil thereof in a fully open position; 
         FIG.  47    is a side elevational view of a distal portion of the interchangeable surgical tool assembly of  FIG.  46    with the anvil thereof in a fully closed position; 
         FIG.  48    is a partial cross-sectional view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  3    with the anvil in a fully open position; 
         FIG.  49    is a partial cross-sectional view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  16    with the anvil in a fully open position; 
         FIG.  50    is a partial cross-sectional view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  19    with the anvil in a fully open position; 
         FIG.  51    is a partial cross-sectional view of the anvil mounting portion and elongate channel of the interchangeable surgical tool assembly of  FIG.  22    with the anvil in a fully open position; 
         FIG.  52    is another partial cross-sectional view of a portion of the interchangeable surgical tool assembly of  FIG.  3    with the anvil of the surgical end effector thereof in a fully open position; 
         FIG.  53    is another partial cross-sectional view of a portion of the interchangeable surgical tool assembly of  FIG.  52    with the anvil in a fully closed position; 
         FIG.  54    is another partial cross-sectional view of a portion of the interchangeable surgical tool assembly of  FIG.  16    wherein the anvil is in a fully open position; 
         FIG.  55    is another partial cross-sectional view of a portion of the interchangeable surgical tool assembly of  FIG.  19    wherein the anvil is in a fully open position; 
         FIG.  56    is another partial cross-sectional view of a portion of the interchangeable surgical tool assembly of  FIG.  22    wherein the anvil is in a fully open position; 
         FIG.  57    is another partial cross-sectional view of a portion of the interchangeable surgical tool assembly of  FIG.  3    wherein the firing member thereof is in a starting position; 
         FIG.  58    is a side elevational view of the surgical end effector of  FIG.  57    with the anvil in a fully closed position; 
         FIG.  59    is another partial cross-sectional view of the portion of the surgical end effector of  FIGS.  57  and  58    wherein the firing member is in initial engagement with the anvil thereof; 
         FIG.  60    is another partial cross-sectional view of the surgical end effector of  FIGS.  57  and  58    after the firing member thereof has been distally advanced during the firing process; 
         FIG.  60 A  is a perspective view of a portion of a firing member assembly of surgical stapling instrument that includes a first firing member element and a second firing member element that is movable relative to the first firing member element between a locked and an unlocked position; 
         FIG.  60 B  is another perspective view of the firing member assembly of  FIG.  60 A  with the second firing member element in the locked position; 
         FIG.  60 C  is a cross-sectional elevational view of the surgical stapling instrument of  FIG.  60 A  with the firing member assembly in a starting position; 
         FIG.  60 D  is another cross-sectional view of the surgical stapling instrument of  FIG.  60 C  illustrated in a locked out configuration; 
         FIG.  60 E  is a side view of a firing member assembly with the second firing member element in a lockout orientation; 
         FIG.  60 F  is another side view of the firing member assembly of  FIG.  60 E  with the second firing member element illustrated in an unlocked or firing orientation; 
         FIG.  60 G  is another partial perspective view of the surgical stapling instrument of  FIG.  60 A  illustrated in an unlocked configuration; 
         FIG.  60 H  is a cross-sectional view of the surgical stapling instrument of  FIG.  60 A  with an unfired surgical fastener cartridge operably supported in an elongate channel thereof and with the firing member assembly illustrated in a starting position; 
         FIG.  60 I  is another cross-sectional view of the surgical stapling instrument of  FIG.  60 H  with the firing member assembly illustrated in a partially-fired configuration; 
         FIG.  61    is another side elevational view of the surgical end effector of  FIGS.  57 - 60    with the anvil in an over closed position; 
         FIG.  62    is a partial side elevational view of the surgical end effector of the interchangeable surgical tool assembly of  FIG.  3    in a fully open position with the distal closure tube segment shown in phantom to illustrate the anvil retaining member; 
         FIG.  63    is another partial side elevational view of the surgical end effector of  FIG.  62    with the anvil in a fully closed position; 
         FIG.  64    is a partial perspective view of a distal closure tube segment of the interchangeable surgical tool assembly of  FIG.  3    with the anvil in a fully closed position; 
         FIG.  65    is a top plan view of the distal closure tube segment and anvil of  FIG.  64   ; 
         FIG.  66    is a partial cross-sectional view of the anvil and distal closure tube segment of  FIGS.  64  and  65    illustrating the position of a proximal jaw opening feature when the anvil is in a fully closed position; 
         FIG.  67    is another partial cross-sectional view of a portion of the anvil and distal closure tube segment of  FIGS.  64 - 66    illustrating the position of the proximal jaw opening feature when the anvil is between the fully open and fully closed positions; 
         FIG.  68    is another partial cross-sectional view of a portion of the anvil and distal closure tube segment of  FIGS.  64 - 67    illustrating the position of the proximal jaw opening feature when the anvil is in the fully open position; 
         FIG.  69    is a partial cross-sectional view of the anvil and distal closure tube segment of  FIGS.  64 - 68    illustrating the position of a distal jaw opening feature when the anvil is in a fully closed position; 
         FIG.  70    is a partial cross-sectional view of the anvil and distal closure tube segment of  FIGS.  64 - 69    illustrating the position of the distal jaw opening feature when the anvil is between the fully open and fully closed positions; 
         FIG.  71    is another partial cross-sectional view of a portion of the anvil and distal closure tube segment of  FIGS.  64 - 70    illustrating the position of the distal jaw opening feature when the anvil is in the fully open position; 
         FIG.  72    is a partial left side perspective view of the anvil and distal closure tube segment of  FIGS.  64 - 71    with the anvil in a fully closed position; 
         FIG.  73    is a partial right side perspective view of the anvil and distal closure tube segment of  FIGS.  64 - 72    with the anvil in a fully closed position; 
         FIG.  74    is a partial left side perspective view of the anvil and distal closure tube segment of  FIGS.  64 - 73    with the anvil in a partially open position; 
         FIG.  75    is a partial right side perspective view of the anvil and distal closure tube segment of  FIGS.  64 - 74    with the anvil in a partially open position; 
         FIG.  76    is a partial left side perspective view of the anvil and distal closure tube segment of  FIGS.  64 - 75    with the anvil in a fully open position; 
         FIG.  77    is a partial right side perspective view of the anvil and distal closure tube segment of  FIGS.  64 - 76    with the anvil in a fully open position; 
         FIG.  78    is a graphical comparison between the jaw aperture angle and retraction of the distal closure tube segment of  FIGS.  64 - 77   ; 
         FIG.  79    is a partial plan view of an end effector of a surgical instrument in accordance with at least one embodiment; 
         FIG.  79 A  is a partial plan view of the end effector of  FIG.  79    illustrating the end effector articulated in a first direction; 
         FIG.  79 B  is a partial plan view of the end effector of  FIG.  79    illustrating the end effector articulated in a second direction; 
         FIG.  80    is a partial plan view of an end effector of a surgical instrument in accordance with at least one embodiment; 
         FIG.  80 A  is a partial plan view of the end effector of  FIG.  80    illustrating the end effector articulated in a first direction; 
         FIG.  80 B  is a partial plan view of the end effector of  FIG.  80    illustrating the end effector articulated in a second direction; 
         FIG.  81    is a partial plan view of the end effector of  FIG.  79   ; 
         FIG.  82    is a partial plan view of the end effector of  FIG.  80   ; 
         FIG.  83    is a partial plan view of the end effector of  FIG.  79    in an articulated position; 
         FIG.  84    is a partial plan view of the end effector of  FIG.  80    in an articulated position; 
         FIG.  85    is a schematic illustrating an articulation range of the end effector of  FIG.  79   ; 
         FIG.  86    is a schematic illustrating an articulation range of the end effector of  FIG.  80   ; 
         FIG.  87    is a partial perspective view of the end effector of  FIG.  80    illustrated with some components removed; 
         FIG.  88    is a partial plan view of the end effector of  FIG.  80    illustrated with some components removed; 
         FIG.  89    is a partial plan view of the end effector of  FIG.  80    illustrated in an open, unarticulated configuration; 
         FIG.  89 A  is a partial plan view of the end effector of  FIG.  80    illustrated in an open, fully-right articulated configuration; 
         FIG.  89 B  is a partial plan view of the end effector of  FIG.  80    illustrated in an open, fully-left articulated configuration; 
         FIG.  90    is a partial plan view of the end effector of  FIG.  80    illustrated in a closed, unarticulated configuration; 
         FIG.  90 A  is a partial plan view of the end effector of  FIG.  80    illustrated in a closed, fully-right articulated configuration; 
         FIG.  90 B  is a partial plan view of the end effector of  FIG.  80    illustrated in a closed, fully-left articulated configuration; 
         FIG.  91    is a partial plan view of the end effector of  FIG.  80    illustrated in an unarticulated configuration; 
         FIG.  92    is a partial plan view of the end effector of  FIG.  80    illustrated in an articulated configuration; 
         FIG.  93    is a partial plan view of the end effector of  FIG.  80    illustrated in an unarticulated configuration; 
         FIG.  93 A  is a partial plan view of the end effector of  FIG.  80    illustrated in a fully-right articulated configuration; 
         FIG.  93 B  is a partial plan view of the end effector of  FIG.  80    illustrated in a fully-left articulated configuration; 
         FIG.  94    is a partial plan view of the end effector of  FIG.  80    illustrated in an unarticulated configuration; 
         FIG.  94 A  is a partial plan view of the end effector of  FIG.  80    illustrated in a fully-right articulated configuration; 
         FIG.  94 B  is a partial plan view of the end effector of  FIG.  80    illustrated in a fully-left articulated configuration; 
         FIG.  95    is a partial perspective view of an end effector in accordance with at least one embodiment; 
         FIG.  96    is a partial plan view of the end effector of  FIG.  95   ; 
         FIG.  97    is a cross-sectional view of the end effector of  FIG.  95    illustrated in an unarticulated configuration; 
         FIG.  97 A  is a cross-sectional view of the end effector of  FIG.  95    illustrated in an articulated configuration; 
         FIG.  97 B  is a cross-sectional view of the end effector of  FIG.  95    illustrated in an articulated configuration; 
         FIG.  98    is a partial perspective view of an end effector in accordance with at least one embodiment; 
         FIG.  99    is a partial perspective view of the end effector of  FIG.  98    illustrated with some components removed; 
         FIG.  100    is a partial plan view of the end effector of  FIG.  98    illustrated with some components removed; 
         FIG.  101    is a partial elevational view of the end effector of  FIG.  98    illustrated with some components removed; 
         FIG.  102    is a cross-sectional view of the end effector of  FIG.  98    illustrated in an unarticulated configuration; 
         FIG.  102 A  is a cross-sectional view of the end effector of  FIG.  98    illustrated in an articulated configuration; 
         FIG.  102 B  is a cross-sectional view of the end effector of  FIG.  98    illustrated in an articulated configuration; 
         FIG.  103    is a partial cross-sectional view of an end effector comprising an articulation system including an articulation lock in accordance with at least one embodiment; 
         FIG.  104    is a partial exploded view of the end effector of  FIG.  103   ; 
         FIG.  105    is a cross-sectional end view of the end effector of  FIG.  103   ; 
         FIG.  106    is a partial cross-sectional view of the end effector of  FIG.  103    illustrating the articulation lock in an engaged condition; 
         FIG.  107    is a partial cross-sectional view of the end effector of  FIG.  103    illustrating the articulation lock in an unlocked condition; 
         FIG.  108    is a partial cross-sectional view of the end effector of  FIG.  103    illustrating the articulation lock in a locked condition; 
         FIG.  109    is a partial cross-sectional view of an end effector including a slidable lock plate in accordance with at least one embodiment; 
         FIG.  110    is a partial cross-sectional view of another end effector including a slidable lock plate in accordance with at least one embodiment; 
         FIG.  111    is a partial cross-sectional view of the end effector of  FIG.  110    illustrating self-adjustability of the lock plate; 
         FIG.  112    is a partial cross-sectional view of the end effector of  FIG.  110    in a locked condition; 
         FIG.  113    is a partial cross-sectional view of an end effector including another slidable lock plate in accordance with at least one embodiment; 
         FIG.  114    is a partial cross-sectional view of the end effector of  FIG.  113    illustrated in a locked condition; 
         FIG.  115    is a partial cross-sectional view of the end effector of  FIG.  113    illustrated in another locked condition; 
         FIG.  116    is a partial cross-sectional view of an end effector comprising an articulation system and an articulation lock in accordance with at least one embodiment illustrated with some components removed; 
         FIG.  116 A  is a partial cross-sectional view of the end effector of  FIG.  116    articulated in a first direction; 
         FIG.  116 B  is a partial cross-sectional view of the end effector of  FIG.  116    articulated in a second direction; 
         FIG.  117    is a partial cross-sectional view of the end effector of  FIG.  116    in an unlocked condition; 
         FIG.  118    is a partial cross-sectional view of the end effector of  FIG.  116    in a partially-locked condition; 
         FIG.  119    is a partial cross-sectional view of the end effector of  FIG.  116    in a locked condition; 
         FIG.  120    is a chart illustrating the gradual locking of the end effector of  FIG.  116   ; 
         FIG.  121    is a partial cross-sectional view of an end effector comprising an articulation system and an articulation lock in accordance with at least one embodiment illustrated with some components removed; 
         FIG.  122    is a partial cross-sectional view of the end effector of  FIG.  121    illustrated in a partially-locked condition; 
         FIG.  123    is a partial cross-sectional view of the end effector of  FIG.  121    in a locked condition; 
         FIG.  124    is a partial cross-sectional view of an end effector comprising an articulation system and an articulation lock in accordance with at least one embodiment illustrated with some components removed; 
         FIG.  125    is a partial cross-sectional view of the end effector of  FIG.  124    illustrating the articulation lock being moved toward the articulation system; 
         FIG.  126    is a partial cross-sectional view of the end effector of  FIG.  124    illustrating the articulation lock engaged with the articulation system; 
         FIG.  127    is a partial cross-sectional view of the end effector of  FIG.  124    illustrating the articulation lock in a locked condition; 
         FIG.  128    is another partial cross-sectional view of the end effector of  FIG.  124    illustrating the articulation lock in its locked condition; 
         FIG.  129    is a partial cross-sectional view of an end effector comprising an articulation system and an articulation lock in accordance with at least one embodiment illustrated with some components removed; 
         FIG.  130    is a partial cross-sectional view of the end effector of  FIG.  129    illustrating the articulation lock engaged with the articulation system; 
         FIG.  131    is a partial cross-sectional view of the end effector of  FIG.  129    illustrating the articulation lock in a locked condition; 
         FIG.  132    is a partial cross-sectional view of an end effector comprising an articulation system and an articulation lock in accordance with at least one embodiment illustrated with some components removed; 
         FIG.  133    is a partial cross-sectional view of the end effector of  FIG.  132    illustrating the articulation lock being moved toward the articulation system; 
         FIG.  134    is a partial cross-sectional view of the end effector of  FIG.  132    illustrating the articulation lock in a locked condition; 
         FIG.  135    is a partial perspective view of an end effector articulation drive system in accordance with at least one embodiment; 
         FIG.  136    is a plan view of the end effector articulation drive system of  FIG.  135   ; 
         FIG.  137    is an elevational view of the end effector articulation drive system of  FIG.  135   ; 
         FIG.  138    is a partial perspective view of an end effector articulation drive system in accordance with at least one embodiment; 
         FIG.  139    is a plan view of the end effector articulation drive system of  FIG.  138   ; 
         FIG.  140    is an elevational view of the end effector articulation drive system of  FIG.  138   ; 
         FIG.  141    is a detail view of the end effector articulation drive system of  FIG.  138   ; 
         FIG.  142    is another detail view of the end effector articulation drive system of  FIG.  138   ; 
         FIG.  143    is a perspective view of a surgical instrument in accordance with at least one embodiment comprising a shaft and an end effector; 
         FIG.  144    is a perspective view of the surgical instrument in  FIG.  143    illustrating the end effector articulated relative to the shaft; 
         FIG.  145    is a perspective view of the end effector of  FIG.  143    in an open configuration; 
         FIG.  146    is a partial elevational view of a firing member in accordance with at least one embodiment; 
         FIG.  147    is a partial cross-sectional plan view of the firing member of  FIG.  146   ; 
         FIG.  148    is a partial cross-sectional view of a distal end of a staple cartridge with a shortened nose in accordance with at least one embodiment; 
         FIG.  149    is a partial cross-sectional view of a distal end of a staple cartridge with an elongate nose in accordance with at least one embodiment; 
         FIG.  150    is a top view of various internal components of the staple cartridge of  FIG.  148    illustrating a triple staple driver spanning across three longitudinal rows of staple cavities positioned on top of a portion of a wedge sled; 
         FIG.  151    is a cross-sectional view of the triple staple driver of  FIG.  150    illustrating the centerline of the triple staple driver with respect to the sled; 
         FIG.  152    is a partial plan view of the staple cartridge of  FIG.  148    illustrating one side of the staple cartridge deck in cross-section and showing the position of the sled of  FIG.  151    within recesses defined in the shortened nose of the cartridge after the completion of a firing stroke; 
         FIG.  153    is a partial cross-sectional view of the staple cartridge of  FIG.  148    taken along line  153 - 153  in  FIG.  152    illustrating the position of the sled after the completion of a firing stroke; 
         FIG.  154    is a diagram comparing the accessibility of end effectors comprising the staple cartridges in  FIGS.  148  and  149    during a surgical procedure in a pelvic cavity; 
         FIG.  155    is a partial perspective view of an end effector comprising the staple cartridge of  FIG.  148    and a shortened opposing anvil with a protective tip in accordance with at least one embodiment; 
         FIG.  156    is a partial elevational view of the end effector of  FIG.  155   ; 
         FIG.  157    is a partial plan view of one embodiment of the anvil depicted in  FIG.  155    with a protective tip in an assembled configuration; 
         FIG.  158    is a partial cross-sectional view of the anvil depicted in  FIG.  157    taken along line  158 - 158  in  FIG.  157    and illustrated in a partially disassembled configuration showing exemplary attachment means for removably affixing the protective tip to the anvil; 
         FIG.  159    is a partial cross-sectional view of the anvil depicted in  FIG.  158    taken along line  159 - 159  in  FIG.  158    and illustrated in a partially disassembled configuration showing the geometry of an attachment feature on the anvil for connection to corresponding geometry on the protective tip; 
         FIG.  160    is a partial cross-sectional view of an additional embodiment of the anvil depicted in  FIG.  155    in a partially disassembled configuration, illustrating a protective tip positioned within a temporary holder; 
         FIG.  161    is a cross-sectional view of the anvil depicted in  FIG.  160    taken along line  161 - 161  in  FIG.  160    in a partially disassembled configuration, showing the geometry of a tip attachment feature on the anvil; 
         FIG.  162    is a cross-sectional view of the anvil depicted in  FIG.  160    taken along line  162 - 162  in  FIG.  160    in an assembled configuration with the temporary holder still attached; 
         FIG.  163    is a cross-sectional view of a trocar seal system prior to the insertion of an end effector there through; 
         FIG.  164    is a cross-sectional view of the trocar seal system of  FIG.  163    illustrating the end effector depicted in  FIG.  163    being inserted there through; 
         FIG.  165    is a cross-sectional view of the trocar seal system of  FIG.  163    illustrating the insertion of the end effector depicted in  FIG.  163    there through; 
         FIG.  166    is a cross-sectional view of the trocar seal system of  FIG.  163    illustrating an end effector comprising the shortened staple cartridge of  FIG.  148    and a shortened anvil with a protective tip being inserted there through; 
         FIG.  167    is a cross-sectional view of a trocar seal system of  FIG.  163    prior to an end effector comprising the elongate cartridge of  FIG.  149    and a shortened anvil with a sharp tip being inserted there through; 
         FIG.  168    is a cross-sectional view of the trocar seal system of  FIG.  163    illustrating the end effector depicted in  FIG.  167    being inserted there through; and 
         FIG.  169    is a cross-sectional view of the trocar seal system of  FIG.  163    illustrating the end effector depicted in  FIG.  167    being inserted there through. 
     
    
    
     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 Jun. 28, 2017 and which are each herein incorporated by reference in their respective entireties:
     U.S. patent application Ser. No. 15/635,693, entitled SURGICAL INSTRUMENT COMPRISING AN OFFSET ARTICULATION JOINT, now U.S. Patent Application Publication No. 2019/0000466;   U.S. patent application Ser. No. 15/635,729, entitled SURGICAL INSTRUMENT COMPRISING AN ARTICULATION SYSTEM RATIO, now U.S. Patent Application Publication No. 2019/0000467;   U.S. patent application Ser. No. 15/635,785, entitled SURGICAL INSTRUMENT COMPRISING AN ARTICULATION SYSTEM RATIO, now U.S. Patent Application Publication No. 2019/0000469;   U.S. patent application Ser. No. 15/635,808, entitled SURGICAL INSTRUMENT COMPRISING FIRING MEMBER SUPPORTS, now U.S. Patent Application Publication No. 2019/0000471;   U.S. patent application Ser. No. 15/635,837, entitled SURGICAL INSTRUMENT COMPRISING AN ARTICULATION SYSTEM LOCKABLE TO A FRAME, now U.S. Patent Application Publication No. 2019/0000472;   U.S. patent application Ser. No. 15/635,941, entitled SURGICAL INSTRUMENT COMPRISING AN ARTICULATION SYSTEM LOCKABLE BY A CLOSURE SYSTEM, now U.S. Patent Application Publication No. 2019/0000473;   U.S. patent application Ser. No. 15/636,029, entitled SURGICAL INSTRUMENT COMPRISING A SHAFT INCLUDING A HOUSING ARRANGEMENT, now U.S. Patent Application Publication No. 2019/0000477;   U.S. patent application Ser. No. 15/635,958, entitled SURGICAL INSTRUMENT COMPRISING SELECTIVELY ACTUATABLE ROTATABLE COUPLERS, now U.S. Patent Application Publication No. 2019/0000474;   U.S. patent application Ser. No. 15/635,981, entitled SURGICAL STAPLING INSTRUMENTS COMPRISING SHORTENED STAPLE CARTRIDGE NOSES, now U.S. Patent Application Publication No. 2019/0000475;   U.S. patent application Ser. No. 15/636,009, entitled SURGICAL INSTRUMENT COMPRISING A SHAFT INCLUDING A CLOSURE TUBE PROFILE, now U.S. Patent Application Publication No. 2019/0000476;   U.S. patent application Ser. No. 15/635,530, entitled SURGICAL INSTRUMENTS WITH ARTICULATABLE END EFFECTOR WITH AXIALLY SHORTENED ARTICULATION JOINT CONFIGURATIONS, now U.S. Patent Application Publication No. 2019/0000457;   U.S. patent application Ser. No. 15/635,549, entitled SURGICAL INSTRUMENTS WITH OPEN AND CLOSABLE JAWS AND AXIALLY MOVABLE FIRING MEMBER THAT IS INITIALLY PARKED IN CLOSE PROXIMITY TO THE JAWS PRIOR TO FIRING, now U.S. Pat. No. 10,588,633;   U.S. patent application Ser. No. 15/635,559, entitled SURGICAL INSTRUMENTS WITH JAWS CONSTRAINED TO PIVOT ABOUT AN AXIS UPON CONTACT WITH A CLOSURE MEMBER THAT IS PARKED IN CLOSE PROXIMITY TO THE PIVOT AXIS, now U.S. Patent Application Publication No. 2019/0000459;   U.S. patent application Ser. No. 15/635,578, entitled SURGICAL END EFFECTORS WITH IMPROVED JAW APERTURE ARRANGEMENTS, now U.S. Patent Application Publication No. 2019/0000460;   U.S. patent application Ser. No. 15/635,594, entitled SURGICAL CUTTING AND FASTENING DEVICES WITH PIVOTABLE ANVIL WITH A TISSUE LOCATING ARRANGEMENT IN CLOSE PROXIMITY TO AN ANVIL PIVOT, now U.S. Patent Application Publication No. 2019/0000461;   U.S. patent application Ser. No. 15/635,612, entitled JAW RETAINER ARRANGEMENT FOR RETAINING A PIVOTABLE SURGICAL INSTRUMENT JAW IN PIVOTABLE RETAINING ENGAGEMENT WITH A SECOND SURGICAL INSTRUMENT JAW, now U.S. Patent Application Publication No. 2019/0000462;   U.S. patent application Ser. No. 15/635,621, entitled SURGICAL INSTRUMENT WITH POSITIVE JAW OPENING FEATURES, now U.S. Patent Application Publication No. 2019/0000463;   U.S. patent application Ser. No. 15/635,631, entitled SURGICAL INSTRUMENT WITH AXIALLY MOVABLE CLOSURE MEMBER, now U.S. Patent Application Publication No. 2019/0000464;   U.S. patent application Ser. No. 15/635,521, entitled SURGICAL INSTRUMENT LOCKOUT ARRANGEMENT, now U.S. Patent Application Publication No. 2019/0000456;   U.S. Design patent application Ser. No. 29/609,087, entitled STAPLE FORMING ANVIL, now U.S. Design Pat. No. D851,762;   U.S. Design patent application Ser. No. 29/609,083, entitled SURGICAL INSTRUMENT SHAFT, now U.S. Design Pat. No. D854,151; and   U.S. Design patent application Ser. No. 29/609,093, entitled SURGICAL FASTENER CARTRIDGE, now U.S. Design Pat. No. D869,655.   

     Applicant of the present application owns the following U.S. Patent Applications that were filed on Jun. 27, 2017 and which are each herein incorporated by reference in their respective entireties:
     U.S. patent application Ser. No. 15/634,024, entitled SURGICAL ANVIL MANUFACTURING METHODS, now U.S. Patent Application Publication No. 2018/0368839;   U.S. patent application Ser. No. 15/634,035, entitled SURGICAL ANVIL ARRANGEMENTS, now U.S. Patent Application Publication No. 2018/0368840;   U.S. patent application Ser. No. 15/634,046, entitled SURGICAL ANVIL ARRANGEMENTS, now U.S. Patent Application Publication No. 2018/0368841;   U.S. patent application Ser. No. 15/634,054, entitled SURGICAL ANVIL ARRANGEMENTS, now U.S. Patent Application Publication No. 2018/0368842;   U.S. patent application Ser. No. 15/634,068, entitled SURGICAL FIRING MEMBER ARRANGEMENTS, now U.S. Patent Application Publication No. 2018/0368843;   U.S. patent application Ser. No. 15/634,076, entitled STAPLE FORMING POCKET ARRANGEMENTS, now U.S. Patent Application Publication No. 2018/0368844;   U.S. patent application Ser. No. 15/634,090 entitled STAPLE FORMING POCKET ARRANGEMENTS, now U.S. Patent Application Publication No. 2018/0368845;   U.S. patent application Ser. No. 15/634,099, entitled SURGICAL END EFFECTORS AND ANVILS, now U.S. Patent Application Publication No. 2018/0368846; and   U.S. patent application Ser. No. 15/634,117, entitled ARTICULATION SYSTEMS FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,631,859.   

     Applicant of the present application owns the following U.S. Patent Applications that were filed on Dec. 21, 2016 and which are each herein incorporated by reference in their respective entireties:
     U.S. patent application Ser. No. 15/386,185, entitled SURGICAL STAPLING INSTRUMENTS AND REPLACEABLE TOOL ASSEMBLIES THEREOF, now U.S. Patent Application Publication No. 2018/0168642;   U.S. patent application Ser. No. 15/386,230, entitled ARTICULATABLE SURGICAL STAPLING INSTRUMENTS, now U.S. Patent Application Publication No. 2018/0168649;   U.S. patent application Ser. No. 15/386,221, entitled LOCKOUT ARRANGEMENTS FOR SURGICAL END EFFECTORS, now U.S. Patent Application Publication No. 2018/0168646;   U.S. patent application Ser. No. 15/386,209, entitled SURGICAL END EFFECTORS AND FIRING MEMBERS THEREOF, now U.S. Pat. No. 10,588,632;   U.S. patent application Ser. No. 15/386,198, entitled LOCKOUT ARRANGEMENTS FOR SURGICAL END EFFECTORS AND REPLACEABLE TOOL ASSEMBLIES, now U.S. Pat. No. 10,610,224;   U.S. patent application Ser. No. 15/386,240, entitled SURGICAL END EFFECTORS AND ADAPTABLE FIRING MEMBERS THEREFOR, now U.S. Patent Application Publication No. 2018/0168651;   U.S. patent application Ser. No. 15/385,939, entitled STAPLE CARTRIDGES AND ARRANGEMENTS OF STAPLES AND STAPLE CAVITIES THEREIN, now U.S. Patent Application Publication No. 2018/0168629;   U.S. patent application Ser. No. 15/385,941, entitled SURGICAL TOOL ASSEMBLIES WITH CLUTCHING ARRANGEMENTS FOR SHIFTING BETWEEN CLOSURE SYSTEMS WITH CLOSURE STROKE REDUCTION FEATURES AND ARTICULATION AND FIRING SYSTEMS, now U.S. Patent Application Publication No. 2018/0168630;   U.S. patent application Ser. No. 15/385,943, entitled SURGICAL STAPLING INSTRUMENTS AND STAPLE-FORMING ANVILS, now U.S. Patent Application Publication No. 2018/0168631;   U.S. patent application Ser. No. 15/385,950, entitled SURGICAL TOOL ASSEMBLIES WITH CLOSURE STROKE REDUCTION FEATURES, now U.S. Pat. No. 10,588,630;   U.S. patent application Ser. No. 15/385,945, entitled STAPLE CARTRIDGES AND ARRANGEMENTS OF STAPLES AND STAPLE CAVITIES THEREIN, now U.S. Patent Application Publication No. 2018/0168632;   U.S. patent application Ser. No. 15/385,946, entitled SURGICAL STAPLING INSTRUMENTS AND STAPLE-FORMING ANVILS, now U.S. Patent Application Publication No. 2018/0168633;   U.S. patent application Ser. No. 15/385,951, entitled SURGICAL INSTRUMENTS WITH JAW OPENING FEATURES FOR INCREASING A JAW OPENING DISTANCE, now U.S. Pat. No. 10,568,626;   U.S. patent application Ser. No. 15/385,953, entitled METHODS OF STAPLING TISSUE, now U.S. Patent Application Publication No. 2018/0168637;   U.S. patent application Ser. No. 15/385,954, entitled FIRING MEMBERS WITH NON-PARALLEL JAW ENGAGEMENT FEATURES FOR SURGICAL END EFFECTORS, now U.S. Pat. No. 10,624,635;   U.S. patent application Ser. No. 15/385,955, entitled SURGICAL END EFFECTORS WITH EXPANDABLE TISSUE STOP ARRANGEMENTS, now U.S. Patent Application Publication No. 2018/0168639;   U.S. patent application Ser. No. 15/385,948, entitled SURGICAL STAPLING INSTRUMENTS AND STAPLE-FORMING ANVILS, now U.S. Patent Application Publication No. 2018/0168584;   U.S. patent application Ser. No. 15/385,956, entitled SURGICAL INSTRUMENTS WITH POSITIVE JAW OPENING FEATURES, now U.S. Pat. No. 10,588,631;   U.S. patent application Ser. No. 15/385,958, entitled SURGICAL INSTRUMENTS WITH LOCKOUT ARRANGEMENTS FOR PREVENTING FIRING SYSTEM ACTUATION UNLESS AN UNSPENT STAPLE CARTRIDGE IS PRESENT, now U.S. Patent Application Publication No. 2018/0168641;   U.S. patent application Ser. No. 15/385,947, entitled STAPLE CARTRIDGES AND ARRANGEMENTS OF STAPLES AND STAPLE CAVITIES THEREIN, now U.S. Pat. No. 10,568,625;   U.S. patent application Ser. No. 15/385,896, entitled METHOD FOR RESETTING A FUSE OF A SURGICAL INSTRUMENT SHAFT, now U.S. Patent Application Publication No. 2018/0168597;   U.S. patent application Ser. No. 15/385,898, entitled STAPLE FORMING POCKET ARRANGEMENT TO ACCOMMODATE DIFFERENT TYPES OF STAPLES, now U.S. Pat. No. 10,537,325;   U.S. patent application Ser. No. 15/385,899, entitled SURGICAL INSTRUMENT COMPRISING IMPROVED JAW CONTROL, now U.S. Patent Application Publication No. 2018/0168600;   U.S. patent application Ser. No. 15/385,901, entitled STAPLE CARTRIDGE AND STAPLE CARTRIDGE CHANNEL COMPRISING WINDOWS DEFINED THEREIN, now U.S. Patent Application Publication No. 2018/0168602;   U.S. patent application Ser. No. 15/385,902, entitled SURGICAL INSTRUMENT COMPRISING A CUTTING MEMBER, now U.S. Patent Application Publication No. 2018/0168603;   U.S. patent application Ser. No. 15/385,904, entitled STAPLE FIRING MEMBER COMPRISING A MISSING CARTRIDGE AND/OR SPENT CARTRIDGE LOCKOUT, now U.S. Patent Application Publication No. 2018/0168605;   U.S. patent application Ser. No. 15/385,905, entitled FIRING ASSEMBLY COMPRISING A LOCKOUT, now U.S. Patent Application Publication No. 2018/0168606;   U.S. patent application Ser. No. 15/385,907, entitled SURGICAL INSTRUMENT SYSTEM COMPRISING AN END EFFECTOR LOCKOUT AND A FIRING ASSEMBLY LOCKOUT, now U.S. Patent Application Publication No. 2018/0168608;   U.S. patent application Ser. No. 15/385,908, entitled FIRING ASSEMBLY COMPRISING A FUSE, now U.S. Patent Application Publication No. 2018/0168609;   U.S. patent application Ser. No. 15/385,909, entitled FIRING ASSEMBLY COMPRISING A MULTIPLE FAILED-STATE FUSE, now U.S. Patent Application Publication No. 2018/0168610;   U.S. patent application Ser. No. 15/385,920, entitled STAPLE FORMING POCKET ARRANGEMENTS, now U.S. Pat. No. 10,499,914;   U.S. patent application Ser. No. 15/385,913, entitled ANVIL ARRANGEMENTS FOR SURGICAL STAPLE/FASTENERS, now U.S. Patent Application Publication No. 2018/0168614;   U.S. patent application Ser. No. 15/385,914, entitled METHOD OF DEFORMING STAPLES FROM TWO DIFFERENT TYPES OF STAPLE CARTRIDGES WITH THE SAME SURGICAL STAPLING INSTRUMENT, now U.S. Patent Application Publication No. 2018/0168615;   U.S. patent application Ser. No. 15/385,893, entitled BILATERALLY ASYMMETRIC STAPLE FORMING POCKET PAIRS, now U.S. Patent Application Publication No. 2018/0168594;   U.S. patent application Ser. No. 15/385,929, entitled CLOSURE MEMBERS WITH CAM SURFACE ARRANGEMENTS FOR SURGICAL INSTRUMENTS WITH SEPARATE AND DISTINCT CLOSURE AND FIRING SYSTEMS, now U.S. Patent Application Publication No. 2018/0168626;   U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950;   U.S. patent application Ser. No. 15/385,927, entitled SURGICAL STAPLING INSTRUMENTS WITH SMART STAPLE CARTRIDGES, now U.S. Patent Application Publication No. 2018/0168625;   U.S. patent application Ser. No. 15/385,917, entitled STAPLE CARTRIDGE COMPRISING STAPLES WITH DIFFERENT CLAMPING BREADTHS, now U.S. Patent Application Publication No. 2018/0168617;   U.S. patent application Ser. No. 15/385,900, entitled STAPLE FORMING POCKET ARRANGEMENTS COMPRISING PRIMARY SIDEWALLS AND POCKET SIDEWALLS, now U.S. Patent Application Publication No. 2018/0168601;   U.S. patent application Ser. No. 15/385,931, entitled NO-CARTRIDGE AND SPENT CARTRIDGE LOCKOUT ARRANGEMENTS FOR SURGICAL STAPLE/FASTENERS, now U.S. Patent Application Publication No. 2018/0168627;   U.S. patent application Ser. No. 15/385,915, entitled FIRING MEMBER PIN ANGLE, now U.S. Patent Application Publication No. 2018/0168616;   U.S. patent application Ser. No. 15/385,897, entitled STAPLE FORMING POCKET ARRANGEMENTS COMPRISING ZONED FORMING SURFACE GROOVES, now U.S. Patent Application Publication No. 2018/0168598;   U.S. patent application Ser. No. 15/385,922, entitled SURGICAL INSTRUMENT WITH MULTIPLE FAILURE RESPONSE MODES, now U.S. Pat. No. 10,426,471;   U.S. patent application Ser. No. 15/385,924, entitled SURGICAL INSTRUMENT WITH PRIMARY AND SAFETY PROCESSORS, now U.S. Patent Application Publication No. 2018/0168624;   U.S. patent application Ser. No. 15/385,912, entitled SURGICAL INSTRUMENTS WITH JAWS THAT ARE PIVOTABLE ABOUT A FIXED AXIS AND INCLUDE SEPARATE AND DISTINCT CLOSURE AND FIRING SYSTEMS, now U.S. Pat. No. 10,568,624;   U.S. patent application Ser. No. 15/385,910, entitled ANVIL HAVING A KNIFE SLOT WIDTH, now U.S. Pat. No. 10,485,543;   U.S. patent application Ser. No. 15/385,906, entitled FIRING MEMBER PIN CONFIGURATIONS, now U.S. Patent Application Publication No. 2018/0168607;   U.S. patent application Ser. No. 15/386,188, entitled STEPPED STAPLE CARTRIDGE WITH ASYMMETRICAL STAPLES, now U.S. Pat. No. 10,537,324;   U.S. patent application Ser. No. 15/386,192, entitled STEPPED STAPLE CARTRIDGE WITH TISSUE RETENTION AND GAP SETTING FEATURES, now U.S. Patent Application Publication No. 2018/0168643;   U.S. patent application Ser. No. 15/386,206, entitled STAPLE CARTRIDGE WITH DEFORMABLE DRIVER RETENTION FEATURES, now U.S. Patent Application Publication No. 2018/0168586;   U.S. patent application Ser. No. 15/386,226, entitled DURABILITY FEATURES FOR END EFFECTORS AND FIRING ASSEMBLIES OF SURGICAL STAPLING INSTRUMENTS, now U.S. Patent Application Publication No. 2018/0168648;   U.S. patent application Ser. No. 15/386,222, entitled SURGICAL STAPLING INSTRUMENTS HAVING END EFFECTORS WITH POSITIVE OPENING FEATURES, now U.S. Patent Application Publication No. 2018/0168647;   U.S. patent application Ser. No. 15/386,236, entitled CONNECTION PORTIONS FOR DEPOSABLE LOADING UNITS FOR SURGICAL STAPLING INSTRUMENTS, now U.S. Patent Application Publication No. 2018/0168650;   U.S. patent application Ser. No. 15/385,887, entitled METHOD FOR ATTACHING A SHAFT ASSEMBLY TO A SURGICAL INSTRUMENT AND, ALTERNATIVELY, TO A SURGICAL ROBOT, now U.S. Patent Application Publication No. 2018/0168589;   U.S. patent application Ser. No. 15/385,889, entitled SHAFT ASSEMBLY COMPRISING A MANUALLY-OPERABLE RETRACTION SYSTEM FOR USE WITH A MOTORIZED SURGICAL INSTRUMENT SYSTEM, now U.S. Patent Application Publication No. 2018/0168590;   U.S. patent application Ser. No. 15/385,890, entitled SHAFT ASSEMBLY COMPRISING SEPARATELY ACTUATABLE AND RETRACTABLE SYSTEMS, now U.S. Patent Application Publication No. 2018/0168591;   U.S. patent application Ser. No. 15/385,891, entitled SHAFT ASSEMBLY COMPRISING A CLUTCH CONFIGURED TO ADAPT THE OUTPUT OF A ROTARY FIRING MEMBER TO TWO DIFFERENT SYSTEMS, now U.S. Patent Application Publication No. 2018/0168592;   U.S. patent application Ser. No. 15/385,892, entitled SURGICAL SYSTEM COMPRISING A FIRING MEMBER ROTATABLE INTO AN ARTICULATION STATE TO ARTICULATE AN END EFFECTOR OF THE SURGICAL SYSTEM, now U.S. Patent Application Publication No. 2018/0168593;   U.S. patent application Ser. No. 15/385,894, entitled SHAFT ASSEMBLY COMPRISING A LOCKOUT, now U.S. Pat. No. 10,492,785;   U.S. patent application Ser. No. 15/385,895, entitled SHAFT ASSEMBLY COMPRISING FIRST AND SECOND ARTICULATION LOCKOUTS, now U.S. Pat. No. 10,542,982;   U.S. patent application Ser. No. 15/385,916, entitled SURGICAL STAPLING SYSTEMS, now U.S. Patent Application Publication No. 2018/0168575;   U.S. patent application Ser. No. 15/385,918, entitled SURGICAL STAPLING SYSTEMS, now U.S. Patent Application Publication No. 2018/0168618;   U.S. patent application Ser. No. 15/385,919, entitled SURGICAL STAPLING SYSTEMS, now U.S. Patent Application Publication No. 2018/0168619;   U.S. patent application Ser. No. 15/385,921, entitled SURGICAL STAPLE/FASTENER CARTRIDGE WITH MOVABLE CAMMING MEMBER CONFIGURED TO DISENGAGE FIRING MEMBER LOCKOUT FEATURES, now U.S. Patent Application Publication No. 2018/0168621;   U.S. patent application Ser. No. 15/385,923, entitled SURGICAL STAPLING SYSTEMS, now U.S. Patent Application Publication No. 2018/0168623;   U.S. patent application Ser. No. 15/385,925, entitled JAW ACTUATED LOCK ARRANGEMENTS FOR PREVENTING ADVANCEMENT OF A FIRING MEMBER IN A SURGICAL END EFFECTOR UNLESS AN UNFIRED CARTRIDGE IS INSTALLED IN THE END EFFECTOR, now U.S. Pat. No. 10,517,595;   U.S. patent application Ser. No. 15/385,926, entitled AXIALLY MOVABLE CLOSURE SYSTEM ARRANGEMENTS FOR APPLYING CLOSURE MOTIONS TO JAWS OF SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2018/0168577;   U.S. patent application Ser. No. 15/385,928, entitled PROTECTIVE COVER ARRANGEMENTS FOR A JOINT INTERFACE BETWEEN A MOVABLE JAW AND ACTUATOR SHAFT OF A SURGICAL INSTRUMENT, now U.S. Patent Application Publication No. 2018/0168578;   U.S. patent application Ser. No. 15/385,930, entitled SURGICAL END EFFECTOR WITH TWO SEPARATE COOPERATING OPENING FEATURES FOR OPENING AND CLOSING END EFFECTOR JAWS, now U.S. Patent Application Publication No. 2018/0168579;   U.S. patent application Ser. No. 15/385,932, entitled ARTICULATABLE SURGICAL END EFFECTOR WITH ASYMMETRIC SHAFT ARRANGEMENT, now U.S. Patent Application Publication No. 2018/0168628;   U.S. patent application Ser. No. 15/385,933, entitled ARTICULATABLE SURGICAL INSTRUMENT WITH INDEPENDENT PIVOTABLE LINKAGE DISTAL OF AN ARTICULATION LOCK, now U.S. Pat. No. 10,603,036;   U.S. patent application Ser. No. 15/385,934, entitled ARTICULATION LOCK ARRANGEMENTS FOR LOCKING AN END EFFECTOR IN AN ARTICULATED POSITION IN RESPONSE TO ACTUATION OF A JAW CLOSURE SYSTEM, now U.S. Pat. No. 10,582,928;   U.S. patent application Ser. No. 15/385,935, entitled LATERALLY ACTUATABLE ARTICULATION LOCK ARRANGEMENTS FOR LOCKING AN END EFFECTOR OF A SURGICAL INSTRUMENT IN AN ARTICULATED CONFIGURATION, now U.S. Pat. No. 10,524,789; and   U.S. patent application Ser. No. 15/385,936, entitled ARTICULATABLE SURGICAL INSTRUMENTS WITH ARTICULATION STROKE AMPLIFICATION FEATURES, now U.S. Pat. No. 10,517,596.   

     Applicant of the present application owns the following U.S. Patent Applications that were filed on Jun. 24, 2016 and which are each herein incorporated by reference in their respective entireties:
     U.S. patent application Ser. No. 15/191,775, entitled STAPLE CARTRIDGE COMPRISING WIRE STAPLES AND STAMPED STAPLES, now U.S. Patent Application Publication No. 2017/0367695;   U.S. patent application Ser. No. 15/191,807, entitled STAPLING SYSTEM FOR USE WITH WIRE STAPLES AND STAMPED STAPLES, now U.S. Patent Application Publication No. 2017/0367696;   U.S. patent application Ser. No. 15/191,834, entitled STAMPED STAPLES AND STAPLE CARTRIDGES USING THE SAME, now U.S. Pat. No. 10,542,979;   U.S. patent application Ser. No. 15/191,788, entitled STAPLE CARTRIDGE COMPRISING OVERDRIVEN STAPLES, now U.S. Patent Application Publication No. 2017/0367698; and   U.S. patent application Ser. No. 15/191,818, entitled STAPLE CARTRIDGE COMPRISING OFFSET LONGITUDINAL STAPLE ROWS, now U.S. Patent Application Publication No. 2017/0367697.   

     Applicant of the present application owns the following U.S. Patent Applications that were filed on Jun. 24, 2016 and which are each herein incorporated by reference in their respective entireties:
     U.S. Design patent application Ser. No. 29/569,218, entitled SURGICAL FASTENER, now U.S. Design Pat. No. D826,405;   U.S. Design patent application Ser. No. 29/569,227, entitled SURGICAL FASTENER, now U.S. Design Pat. No. D822,206;   U.S. Design patent application Ser. No. 29/569,259, entitled SURGICAL FASTENER CARTRIDGE, now U.S. Design Pat. No. D847,989; and   U.S. Design patent application Ser. No. 29/569,264, entitled SURGICAL FASTENER CARTRIDGE, now U.S. Design Pat. No. D850,617.   

     Applicant of the present application owns the following patent applications that were filed on Apr. 1, 2016 and which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 15/089,325, entitled METHOD FOR OPERATING A SURGICAL STAPLING SYSTEM, now U.S. Patent Application Publication No. 2017/0281171;   U.S. patent application Ser. No. 15/089,321, entitled MODULAR SURGICAL STAPLING SYSTEM COMPRISING A DISPLAY, now U.S. Pat. No. 10,271,851;   U.S. patent application Ser. No. 15/089,326, entitled SURGICAL STAPLING SYSTEM COMPRISING A DISPLAY INCLUDING A RE-ORIENTABLE DISPLAY FIELD, now U.S. Pat. No. 10,433,849;   U.S. patent application Ser. No. 15/089,263, entitled SURGICAL INSTRUMENT HANDLE ASSEMBLY WITH RECONFIGURABLE GRIP PORTION, now U.S. Pat. No. 10,307,159;   U.S. patent application Ser. No. 15/089,262, entitled ROTARY POWERED SURGICAL INSTRUMENT WITH MANUALLY ACTUATABLE BAILOUT SYSTEM, now U.S. Pat. No. 10,357,246;   U.S. patent application Ser. No. 15/089,277, entitled SURGICAL CUTTING AND STAPLING END EFFECTOR WITH ANVIL CONCENTRIC DRIVE MEMBER, now U.S. Pat. No. 10,531,874;   U.S. patent application Ser. No. 15/089,296, entitled INTERCHANGEABLE SURGICAL TOOL ASSEMBLY WITH A SURGICAL END EFFECTOR THAT IS SELECTIVELY ROTATABLE ABOUT A SHAFT AXIS, now U.S. Pat. No. 10,413,293;   U.S. patent application Ser. No. 15/089,258, entitled SURGICAL STAPLING SYSTEM COMPRISING A SHIFTABLE TRANSMISSION, now U.S. Pat. No. 10,342,543;   U.S. patent application Ser. No. 15/089,278, entitled SURGICAL STAPLING SYSTEM CONFIGURED TO PROVIDE SELECTIVE CUTTING OF TISSUE, now U.S. Pat. No. 10,420,552;   U.S. patent application Ser. No. 15/089,284, entitled SURGICAL STAPLING SYSTEM COMPRISING A CONTOURABLE SHAFT, now U.S. Patent Application Publication No. 2017/0281186;   U.S. patent application Ser. No. 15/089,295, entitled SURGICAL STAPLING SYSTEM COMPRISING A TISSUE COMPRESSION LOCKOUT, now U.S. Patent Application Publication No. 2017/0281187;   U.S. patent application Ser. No. 15/089,300, entitled SURGICAL STAPLING SYSTEM COMPRISING AN UNCLAMPING LOCKOUT, now U.S. Pat. No. 10,456,140;   U.S. patent application Ser. No. 15/089,196, entitled SURGICAL STAPLING SYSTEM COMPRISING A JAW CLOSURE LOCKOUT, now U.S. Pat. No. 10,568,632;   U.S. patent application Ser. No. 15/089,203, entitled SURGICAL STAPLING SYSTEM COMPRISING A JAW ATTACHMENT LOCKOUT, now U.S. Pat. No. 10,542,991;   U.S. patent application Ser. No. 15/089,210, entitled SURGICAL STAPLING SYSTEM COMPRISING A SPENT CARTRIDGE LOCKOUT, now U.S. Pat. No. 10,478,190;   U.S. patent application Ser. No. 15/089,324, entitled SURGICAL INSTRUMENT COMPRISING A SHIFTING MECHANISM, now U.S. Pat. No. 10,314,582;   U.S. patent application Ser. No. 15/089,335, entitled SURGICAL STAPLING INSTRUMENT COMPRISING MULTIPLE LOCKOUTS, now U.S. Pat. No. 10,485,542;   U.S. patent application Ser. No. 15/089,339, entitled SURGICAL STAPLING INSTRUMENT, now U.S. Patent Application Publication No. 2017/0281173;   U.S. patent application Ser. No. 15/089,253, entitled SURGICAL STAPLING SYSTEM CONFIGURED TO APPLY ANNULAR ROWS OF STAPLES HAVING DIFFERENT HEIGHTS, now U.S. Pat. No. 10,413,297;   U.S. patent application Ser. No. 15/089,304, entitled SURGICAL STAPLING SYSTEM COMPRISING A GROOVED FORMING POCKET, now U.S. Pat. No. 10,285,705;   U.S. patent application Ser. No. 15/089,331, entitled ANVIL MODIFICATION MEMBERS FOR SURGICAL STAPLE/FASTENERS, now U.S. Pat. No. 10,376,263;   U.S. patent application Ser. No. 15/089,336, entitled STAPLE CARTRIDGES WITH ATRAUMATIC FEATURES, now U.S. Patent Application Publication No. 2017/0281164;   U.S. patent application Ser. No. 15/089,312, entitled CIRCULAR STAPLING SYSTEM COMPRISING AN INCISABLE TISSUE SUPPORT, now U.S. Patent Application Publication No. 2017/0281189;   U.S. patent application Ser. No. 15/089,309, entitled CIRCULAR STAPLING SYSTEM COMPRISING ROTARY FIRING SYSTEM, now U.S. Patent Application Publication No. 2017/0281169; and   U.S. patent application Ser. No. 15/089,349, entitled CIRCULAR STAPLING SYSTEM COMPRISING LOAD CONTROL, now U.S. Patent Application Publication No. 2017/0281174.   

     Applicant of the present application also owns the U.S. Patent Applications identified below which were filed on Dec. 31, 2015 which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 14/984,488, entitled MECHANISMS FOR COMPENSATING FOR BATTERY PACK FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,292,704;   U.S. patent application Ser. No. 14/984,525, entitled MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,368,865; and   U.S. patent application Ser. No. 14/984,552, entitled SURGICAL INSTRUMENTS WITH SEPARABLE MOTORS AND MOTOR CONTROL CIRCUITS, now U.S. Pat. No. 10,265,068.   

     Applicant of the present application also owns the U.S. Patent Applications identified below which were filed on Feb. 9, 2016 which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 15/019,220, entitled SURGICAL INSTRUMENT WITH ARTICULATING AND AXIALLY TRANSLATABLE END EFFECTOR, now U.S. Pat. No. 10,245,029;   U.S. patent application Ser. No. 15/019,228, entitled SURGICAL INSTRUMENTS WITH MULTIPLE LINK ARTICULATION ARRANGEMENTS, now U.S. Pat. No. 10,433,837;   U.S. patent application Ser. No. 15/019,196, entitled SURGICAL INSTRUMENT ARTICULATION MECHANISM WITH SLOTTED SECONDARY CONSTRAINT, now U.S. Pat. No. 10,413,291;   U.S. patent application Ser. No. 15/019,206, entitled SURGICAL INSTRUMENTS WITH AN END EFFECTOR THAT IS HIGHLY ARTICULATABLE RELATIVE TO AN ELONGATE SHAFT ASSEMBLY, now U.S. Patent Application Publication No. 2017/0224331;   U.S. patent application Ser. No. 15/019,215, entitled SURGICAL INSTRUMENTS WITH NON-SYMMETRICAL ARTICULATION ARRANGEMENTS, now U.S. Patent Application Publication No. 2017/0224332;   U.S. patent application Ser. No. 15/019,227, entitled ARTICULATABLE SURGICAL INSTRUMENTS WITH SINGLE ARTICULATION LINK ARRANGEMENTS, now U.S. Patent Application Publication No. 2017/0224334;   U.S. patent application Ser. No. 15/019,235, entitled SURGICAL INSTRUMENTS WITH TENSIONING ARRANGEMENTS FOR CABLE DRIVEN ARTICULATION SYSTEMS, now U.S. Pat. No. 10,245,030;   U.S. patent application Ser. No. 15/019,230, entitled ARTICULATABLE SURGICAL INSTRUMENTS WITH OFF-AXIS FIRING BEAM ARRANGEMENTS, now U.S. Pat. No. 10,588,625; and   U.S. patent application Ser. No. 15/019,245, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764.   

     Applicant of the present application also owns the U.S. Patent Applications identified below which were filed on Feb. 12, 2016 which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 15/043,254, entitled MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,258,331;   U.S. patent application Ser. No. 15/043,259, entitled MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,448,948;   U.S. patent application Ser. No. 15/043,275, entitled MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2017/0231627; and   U.S. patent application Ser. No. 15/043,289, entitled MECHANISMS FOR COMPENSATING FOR DRIVETRAIN FAILURE IN POWERED SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2017/0231628.   

     Applicant of the present application owns the following patent applications that were filed on Jun. 18, 2015 and which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 14/742,925, entitled SURGICAL END EFFECTORS WITH POSITIVE JAW OPENING ARRANGEMENTS, now U.S. Pat. No. 10,182,818;   U.S. patent application Ser. No. 14/742,941, entitled SURGICAL END EFFECTORS WITH DUAL CAM ACTUATED JAW CLOSING FEATURES, now U.S. Pat. No. 10,052,102;   U.S. patent application Ser. No. 14/742,914, entitled MOVABLE FIRING BEAM SUPPORT ARRANGEMENTS FOR ARTICULATABLE SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,405,863;   U.S. patent application Ser. No. 14/742,900, entitled ARTICULATABLE SURGICAL INSTRUMENTS WITH COMPOSITE FIRING BEAM STRUCTURES WITH CENTER FIRING SUPPORT MEMBER FOR ARTICULATION SUPPORT, now U.S. Pat. No. 10,335,149;   U.S. patent application Ser. No. 14/742,885, entitled DUAL ARTICULATION DRIVE SYSTEM ARRANGEMENTS FOR ARTICULATABLE SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,368,861; and   U.S. patent application Ser. No. 14/742,876, entitled PUSH/PULL ARTICULATION DRIVE SYSTEMS FOR ARTICULATABLE SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,178,992.   

     Applicant of the present application owns the following patent applications that were filed on Mar. 6, 2015 and which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 14/640,746, entitled POWERED SURGICAL INSTRUMENT, now U.S. Pat. No. 9,808,246;   U.S. patent application Ser. No. 14/640,795, entitled MULTIPLE LEVEL THRESHOLDS TO MODIFY OPERATION OF POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,441,279;   U.S. patent application Ser. No. 14/640,832, entitled ADAPTIVE TISSUE COMPRESSION TECHNIQUES TO ADJUST CLOSURE RATES FOR MULTIPLE TISSUE TYPES, now U.S. Patent Application Publication No. 2016/0256154;   U.S. patent application Ser. No. 14/640,935, entitled OVERLAID MULTI SENSOR RADIO FREQUENCY (RF) ELECTRODE SYSTEM TO MEASURE TISSUE COMPRESSION, now U.S. Pat. No. 10,548,504;   U.S. patent application Ser. No. 14/640,831, entitled MONITORING SPEED CONTROL AND PRECISION INCREMENTING OF MOTOR FOR POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,895,148;   U.S. patent application Ser. No. 14/640,859, entitled TIME DEPENDENT EVALUATION OF SENSOR DATA TO DETERMINE STABILITY, CREEP, AND VISCOELASTIC ELEMENTS OF MEASURES, now U.S. Pat. No. 10,052,044;   U.S. patent application Ser. No. 14/640,817, entitled INTERACTIVE FEEDBACK SYSTEM FOR POWERED SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,924,961;   U.S. patent application Ser. No. 14/640,844, entitled CONTROL TECHNIQUES AND SUB-PROCESSOR CONTAINED WITHIN MODULAR SHAFT WITH SELECT CONTROL PROCESSING FROM HANDLE, now U.S. Pat. No. 10,045,776;   U.S. patent application Ser. No. 14/640,837, entitled SMART SENSORS WITH LOCAL SIGNAL PROCESSING, now U.S. Pat. No. 9,993,248;   U.S. patent application Ser. No. 14/640,765, entitled SYSTEM FOR DETECTING THE MIS-INSERTION OF A STAPLE CARTRIDGE INTO A SURGICAL STAPLE/FASTENER, now U.S. Pat. No. 10,617,412;   U.S. patent application Ser. No. 14/640,799, entitled SIGNAL AND POWER COMMUNICATION SYSTEM POSITIONED ON A ROTATABLE SHAFT, now U.S. Pat. No. 9,901,342; and   U.S. patent application Ser. No. 14/640,780, entitled SURGICAL INSTRUMENT COMPRISING A LOCKABLE BATTERY HOUSING, now U.S. Pat. No. 10,245,033.   

     Applicant of the present application owns the following patent applications that were filed on Feb. 27, 2015, and which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 14/633,576, entitled SURGICAL INSTRUMENT SYSTEM COMPRISING AN INSPECTION STATION, now U.S. Pat. No. 10,045,779;   U.S. patent application Ser. No. 14/633,546, entitled SURGICAL APPARATUS CONFIGURED TO ASSESS WHETHER A PERFORMANCE PARAMETER OF THE SURGICAL APPARATUS IS WITHIN AN ACCEPTABLE PERFORMANCE BAND, now U.S. Pat. No. 10,180,463;   U.S. patent application Ser. No. 14/633,560, entitled SURGICAL CHARGING SYSTEM THAT CHARGES AND/OR CONDITIONS ONE OR MORE BATTERIES, now U.S. Patent Application Publication No. 2016/0249910;   U.S. patent application Ser. No. 14/633,566, entitled CHARGING SYSTEM THAT ENABLES EMERGENCY RESOLUTIONS FOR CHARGING A BATTERY, now U.S. Pat. No. 10,182,816;   U.S. patent application Ser. No. 14/633,555, entitled SYSTEM FOR MONITORING WHETHER A SURGICAL INSTRUMENT NEEDS TO BE SERVICED, now U.S. Pat. No. 10,321,907;   U.S. patent application Ser. No. 14/633,542, entitled REINFORCED BATTERY FOR A SURGICAL INSTRUMENT, now U.S. Pat. No. 9,931,118;   U.S. patent application Ser. No. 14/633,548, entitled POWER ADAPTER FOR A SURGICAL INSTRUMENT, now U.S. Pat. No. 10,245,028;   U.S. patent application Ser. No. 14/633,526, entitled ADAPTABLE SURGICAL INSTRUMENT HANDLE, now U.S. Pat. No. 9,993,258;   U.S. patent application Ser. No. 14/633,541, entitled MODULAR STAPLING ASSEMBLY, now U.S. Pat. No. 10,226,250; and   U.S. patent application Ser. No. 14/633,562, entitled SURGICAL APPARATUS CONFIGURED TO TRACK AN END-OF-LIFE PARAMETER, now U.S. Pat. No. 10,159,483.   

     Applicant of the present application owns the following patent applications that were filed on Dec. 18, 2014 and which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 14/574,478, entitled SURGICAL INSTRUMENT SYSTEMS COMPRISING AN ARTICULATABLE END EFFECTOR AND MEANS FOR ADJUSTING THE FIRING STROKE OF A FIRING MEMBER, now U.S. Pat. No. 9,844,374;   U.S. patent application Ser. No. 14/574,483, entitled SURGICAL INSTRUMENT ASSEMBLY COMPRISING LOCKABLE SYSTEMS, now U.S. Pat. No. 10,188,385;   U.S. patent application Ser. No. 14/575,139, entitled DRIVE ARRANGEMENTS FOR ARTICULATABLE SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,844,375;   U.S. patent application Ser. No. 14/575,148, entitled LOCKING ARRANGEMENTS FOR DETACHABLE SHAFT ASSEMBLIES WITH ARTICULATABLE SURGICAL END EFFECTORS, now U.S. Pat. No. 10,085,748;   U.S. patent application Ser. No. 14/575,130, entitled SURGICAL INSTRUMENT WITH AN ANVIL THAT IS SELECTIVELY MOVABLE ABOUT A DISCRETE NON-MOVABLE AXIS RELATIVE TO A STAPLE CARTRIDGE, now U.S. Pat. No. 10,245,027;   U.S. patent application Ser. No. 14/575,143, entitled SURGICAL INSTRUMENTS WITH IMPROVED CLOSURE ARRANGEMENTS, now U.S. Pat. No. 10,004,501;   U.S. patent application Ser. No. 14/575,117, entitled SURGICAL INSTRUMENTS WITH ARTICULATABLE END EFFECTORS AND MOVABLE FIRING BEAM SUPPORT ARRANGEMENTS, now U.S. Pat. No. 9,943,309;   U.S. patent application Ser. No. 14/575,154, entitled SURGICAL INSTRUMENTS WITH ARTICULATABLE END EFFECTORS AND IMPROVED FIRING BEAM SUPPORT ARRANGEMENTS, now U.S. Pat. No. 9,968,355;   U.S. patent application Ser. No. 14/574,493, entitled SURGICAL INSTRUMENT ASSEMBLY COMPRISING A FLEXIBLE ARTICULATION SYSTEM, now U.S. Pat. No. 9,987,000; and   U.S. patent application Ser. No. 14/574,500, entitled SURGICAL INSTRUMENT ASSEMBLY COMPRISING A LOCKABLE ARTICULATION SYSTEM, now U.S. Pat. No. 10,117,649.   

     Applicant of the present application owns the following patent applications that were filed on Mar. 1, 2013 and which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 13/782,295, entitled ARTICULATABLE SURGICAL INSTRUMENTS WITH CONDUCTIVE PATHWAYS FOR SIGNAL COMMUNICATION, now U.S. Pat. No. 9,700,309;   U.S. patent application Ser. No. 13/782,323, entitled ROTARY POWERED ARTICULATION JOINTS FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,782,169;   U.S. patent application Ser. No. 13/782,338, entitled THUMBWHEEL SWITCH ARRANGEMENTS FOR SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2014/0249557;   U.S. patent application Ser. No. 13/782,499, entitled ELECTROMECHANICAL SURGICAL DEVICE WITH SIGNAL RELAY ARRANGEMENT, now U.S. Pat. No. 9,358,003;   U.S. patent application Ser. No. 13/782,460, entitled MULTIPLE PROCESSOR MOTOR CONTROL FOR MODULAR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,554,794;   U.S. patent application Ser. No. 13/782,358, entitled JOYSTICK SWITCH ASSEMBLIES FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,326,767;   U.S. patent application Ser. No. 13/782,481, entitled SENSOR STRAIGHTENED END EFFECTOR DURING REMOVAL THROUGH TROCAR, now U.S. Pat. No. 9,468,438;   U.S. patent application Ser. No. 13/782,518, entitled CONTROL METHODS FOR SURGICAL INSTRUMENTS WITH REMOVABLE IMPLEMENT PORTIONS, now U.S. Patent Application Publication No. 2014/0246475;   U.S. patent application Ser. No. 13/782,375, entitled ROTARY POWERED SURGICAL INSTRUMENTS WITH MULTIPLE DEGREES OF FREEDOM, now U.S. Pat. No. 9,398,911; and   U.S. patent application Ser. No. 13/782,536, entitled SURGICAL INSTRUMENT SOFT STOP, now U.S. Pat. No. 9,307,986.   

     Applicant of the present application also owns the following patent applications that were filed on Mar. 14, 2013 and which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 13/803,097, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING A FIRING DRIVE, now U.S. Pat. No. 9,687,230;   U.S. patent application Ser. No. 13/803,193, entitled CONTROL ARRANGEMENTS FOR A DRIVE MEMBER OF A SURGICAL INSTRUMENT, now U.S. Pat. No. 9,332,987;   U.S. patent application Ser. No. 13/803,053, entitled INTERCHANGEABLE SHAFT ASSEMBLIES FOR USE WITH A SURGICAL INSTRUMENT, now U.S. Pat. No. 9,883,860   U.S. patent application Ser. No. 13/803,086, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. Patent Application Publication No. 2014/0263541;   U.S. patent application Ser. No. 13/803,210, entitled SENSOR ARRANGEMENTS FOR ABSOLUTE POSITIONING SYSTEM FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,808,244;   U.S. patent application Ser. No. 13/803,148, entitled MULTI-FUNCTION MOTOR FOR A SURGICAL INSTRUMENT, now U.S. Pat. No. 10,470,762;   U.S. patent application Ser. No. 13/803,066, entitled DRIVE SYSTEM LOCKOUT ARRANGEMENTS FOR MODULAR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,629,623;   U.S. patent application Ser. No. 13/803,117, entitled ARTICULATION CONTROL SYSTEM FOR ARTICULATABLE SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,351,726;   U.S. patent application Ser. No. 13/803,130, entitled DRIVE TRAIN CONTROL ARRANGEMENTS FOR MODULAR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,351,727; and   U.S. patent application Ser. No. 13/803,159, entitled METHOD AND SYSTEM FOR OPERATING A SURGICAL INSTRUMENT, now U.S. Pat. No. 9,888,919.   

     Applicant of the present application also owns the following patent application that was filed on Mar. 7, 2014 and is herein incorporated by reference in its entirety:
     U.S. patent application Ser. No. 14/200,111, entitled CONTROL SYSTEMS FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 9,629,629.   

     Applicant of the present application also owns the following patent applications that were filed on Mar. 26, 2014 and are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 14/226,106, entitled POWER MANAGEMENT CONTROL SYSTEMS FOR SURGICAL INSTRUMENTS, now U.S. Patent Application Publication No. 2015/0272582;   U.S. patent application Ser. No. 14/226,099, entitled STERILIZATION VERIFICATION CIRCUIT, now U.S. Pat. No. 9,826,977;   U.S. patent application Ser. No. 14/226,094, entitled VERIFICATION OF NUMBER OF BATTERY EXCHANGES/PROCEDURE COUNT, now U.S. Patent Application Publication No. 2015/0272580;   U.S. patent application Ser. No. 14/226,117, entitled POWER MANAGEMENT THROUGH SLEEP OPTIONS OF SEGMENTED CIRCUIT AND WAKE UP CONTROL, now U.S. Pat. No. 10,013,049;   U.S. patent application Ser. No. 14/226,075, entitled MODULAR POWERED SURGICAL INSTRUMENT WITH DETACHABLE SHAFT ASSEMBLIES, now U.S. Pat. No. 9,743,929;   U.S. patent application Ser. No. 14/226,093, entitled FEEDBACK ALGORITHMS FOR MANUAL BAILOUT SYSTEMS FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,028,761;   U.S. patent application Ser. No. 14/226,116, entitled SURGICAL INSTRUMENT UTILIZING SENSOR ADAPTATION, now U.S. Patent Application Publication No. 2015/0272571;   U.S. patent application Ser. No. 14/226,071, entitled SURGICAL INSTRUMENT CONTROL CIRCUIT HAVING A SAFETY PROCESSOR, now U.S. Pat. No. 9,690,362;   U.S. patent application Ser. No. 14/226,097, entitled SURGICAL INSTRUMENT COMPRISING INTERACTIVE SYSTEMS, now U.S. Pat. No. 9,820,738;   U.S. patent application Ser. No. 14/226,126, entitled INTERFACE SYSTEMS FOR USE WITH SURGICAL INSTRUMENTS, now U.S. Pat. No. 10,004,497;   U.S. patent application Ser. No. 14/226,133, entitled MODULAR SURGICAL INSTRUMENT SYSTEM, now U.S. Patent Application Publication No. 2015/0272557;   U.S. patent application Ser. No. 14/226,081, entitled SYSTEMS AND METHODS FOR CONTROLLING A SEGMENTED CIRCUIT, now U.S. Pat. No. 9,804,618;   U.S. patent application Ser. No. 14/226,076, entitled POWER MANAGEMENT THROUGH SEGMENTED CIRCUIT AND VARIABLE VOLTAGE PROTECTION, now U.S. Pat. No. 9,733,663;   U.S. patent application Ser. No. 14/226,111, entitled SURGICAL STAPLING INSTRUMENT SYSTEM, now U.S. Pat. No. 9,750,499; and   U.S. patent application Ser. No. 14/226,125, entitled SURGICAL INSTRUMENT COMPRISING A ROTATABLE SHAFT, now U.S. Pat. No. 10,201,364.   

     Applicant of the present application also owns the following patent applications that were filed on Sep. 5, 2014 and which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 14/479,103, entitled CIRCUITRY AND SENSORS FOR POWERED MEDICAL DEVICE, now U.S. Pat. No. 10,111,679;   U.S. patent application Ser. No. 14/479,119, entitled ADJUNCT WITH INTEGRATED SENSORS TO QUANTIFY TISSUE COMPRESSION, now U.S. Pat. No. 9,724,094;   U.S. patent application Ser. No. 14/478,908, entitled MONITORING DEVICE DEGRADATION BASED ON COMPONENT EVALUATION, now U.S. Pat. No. 9,737,301;   U.S. patent application Ser. No. 14/478,895, entitled MULTIPLE SENSORS WITH ONE SENSOR AFFECTING A SECOND SENSOR&#39;S OUTPUT OR INTERPRETATION, now U.S. Pat. No. 9,757,128;   U.S. patent application Ser. No. 14/479,110, entitled POLARITY OF HALL MAGNET TO DETECT MISLOADED CARTRIDGE, now U.S. Pat. No. 10,016,199;   U.S. patent application Ser. No. 14/479,098, entitled SMART CARTRIDGE WAKE UP OPERATION AND DATA RETENTION, now U.S. Pat. No. 10,135,242;   U.S. patent application Ser. No. 14/479,115, entitled MULTIPLE MOTOR CONTROL FOR POWERED MEDICAL DEVICE, now U.S. Pat. No. 9,788,836; and   U.S. patent application Ser. No. 14/479,108, entitled LOCAL DISPLAY OF TISSUE PARAMETER STABILIZATION, now U.S. Patent Application Publication No. 2016/0066913.   

     Applicant of the present application also owns the following patent applications that were filed on Apr. 9, 2014 and which are each herein incorporated by reference in their respective entirety:
     U.S. patent application Ser. No. 14/248,590, entitled MOTOR DRIVEN SURGICAL INSTRUMENTS WITH LOCKABLE DUAL DRIVE SHAFTS, now U.S. Pat. No. 9,826,976;   U.S. patent application Ser. No. 14/248,581, entitled SURGICAL INSTRUMENT COMPRISING A CLOSING DRIVE AND A FIRING DRIVE OPERATED FROM THE SAME ROTATABLE OUTPUT, now U.S. Pat. No. 9,649,110;   U.S. patent application Ser. No. 14/248,595, entitled SURGICAL INSTRUMENT SHAFT INCLUDING SWITCHES FOR CONTROLLING THE OPERATION OF THE SURGICAL INSTRUMENT, now U.S. Pat. No. 9,844,368;   U.S. patent application Ser. No. 14/248,588, entitled POWERED LINEAR SURGICAL STAPLE/FASTENER, now U.S. Pat. No. 10,405,857;   U.S. patent application Ser. No. 14/248,591, entitled TRANSMISSION ARRANGEMENT FOR A SURGICAL INSTRUMENT, now U.S. Pat. No. 10,149,680;   U.S. patent application Ser. No. 14/248,584, entitled MODULAR MOTOR DRIVEN SURGICAL INSTRUMENTS WITH ALIGNMENT FEATURES FOR ALIGNING ROTARY DRIVE SHAFTS WITH SURGICAL END EFFECTOR SHAFTS, now U.S. Pat. No. 9,801,626;   U.S. patent application Ser. No. 14/248,587, entitled POWERED SURGICAL STAPLE/FASTENER, now U.S. Pat. No. 9,867,612;   U.S. patent application Ser. No. 14/248,586, entitled DRIVE SYSTEM DECOUPLING ARRANGEMENT FOR A SURGICAL INSTRUMENT, now U.S. Pat. No. 10,136,887; and   U.S. patent application Ser. No. 14/248,607, entitled MODULAR MOTOR DRIVEN SURGICAL INSTRUMENTS WITH STATUS INDICATION ARRANGEMENTS, now U.S. Pat. No. 9,814,460.   

     Applicant of the present application also owns the following patent applications that were filed on Apr. 16, 2013 and which are each herein incorporated by reference in their respective entirety:
     U.S. Provisional Patent Application Ser. No. 61/812,365, entitled SURGICAL INSTRUMENT WITH MULTIPLE FUNCTIONS PERFORMED BY A SINGLE MOTOR;   U.S. Provisional Patent Application Ser. No. 61/812,376, entitled LINEAR CUTTER WITH POWER;   U.S. Provisional Patent Application Ser. No. 61/812,382, entitled LINEAR CUTTER WITH MOTOR AND PISTOL GRIP;   U.S. Provisional Patent Application Ser. No. 61/812,385, entitled SURGICAL INSTRUMENT HANDLE WITH MULTIPLE ACTUATION MOTORS AND MOTOR CONTROL; and   U.S. Provisional Patent Application Ser. No. 61/812,372, entitled SURGICAL INSTRUMENT WITH MULTIPLE FUNCTIONS PERFORMED BY A SINGLE MOTOR.   

     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 surgical system  10  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  10  includes four interchangeable surgical tool assemblies  1000 ,  3000 ,  5000  and  7000  that are each adapted for interchangeable use with a handle assembly  500 . Each interchangeable surgical tool assembly  1000 ,  3000 ,  5000  and  7000  may be designed for use in connection with the performance of one or more specific surgical procedures. In another surgical system embodiment, one or more of the interchangeable surgical tool assemblies  1000 ,  3000 ,  5000  and  7000  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. 
       FIG.  2    illustrates attachment of an interchangeable surgical tool assembly  1000  to the handle assembly  500 . It will be understood that any of the other interchangeable tool assemblies  3000 ,  5000 , and  7000  may be coupled to the handle assembly  500  in a similar manner. The attachment arrangement and process depicted in  FIG.  2    may also be employed in connection with attachment of any of the interchangeable surgical tool assemblies  1000 ,  3000 ,  5000  and  7000  to a tool drive portion or tool drive housing of a robotic system. The handle assembly  500  may comprise a handle housing  502  that includes a pistol grip portion  504  that can be gripped and manipulated by the clinician. As will be briefly discussed below, the handle assembly  500  operably supports a plurality of drive systems  510 ,  530  that are configured to generate and apply various control motions to corresponding portions of the interchangeable surgical tool assembly  1000 ,  3000 ,  5000  and/or  7000  that is operably attached thereto. 
     As can be seen in  FIG.  2   , the handle assembly  500  may further include a handle frame  506  that operably supports the plurality of drive systems. For example, the handle frame  506  can operably support a “first” or closure drive system, generally designated as  510 , which may be employed to apply closing and opening motions to the interchangeable surgical tool assembly  1000 ,  3000 ,  5000  and  7000  that is operably attached or coupled to the handle assembly  500 . In at least one form, the closure drive system  510  may include an actuator in the form of a closure trigger  512  that is pivotally supported by the handle frame  506 . Such arrangement enables the closure trigger  512  to be manipulated by a clinician such that when the clinician grips the pistol grip portion  504  of the handle assembly  500 , the closure trigger  512  may be easily pivoted from a starting or “unactuated” position to an “actuated” position and more particularly to a fully compressed or fully actuated position. In various forms, the closure drive system  510  further includes a closure linkage assembly  514  that is pivotally coupled to the closure trigger  512  or otherwise operably interfaces therewith. As will be discussed in further detail below, in the illustrated example, the closure linkage assembly  514  includes a transverse attachment pin  516  that facilitates attachment to a corresponding drive system on the surgical tool assembly. In use, to actuate the closure drive system  510 , the clinician depresses the closure trigger  512  towards the pistol grip portion  504 . As described in further detail in U.S. patent application Ser. No. 14/226,142, entitled SURGICAL INSTRUMENT COMPRISING A SENSOR SYSTEM, U.S. Patent Application Publication No. 2015/0272575, now U.S. Pat. No. 9,913,642, which is hereby incorporated by reference in its entirety herein, when the clinician fully depresses the closure trigger  512  to attain the full closure stroke, the closure drive system  510  is configured to lock the closure trigger  512  into the fully depressed or fully actuated position. When the clinician desires to unlock the closure trigger  512  to permit it to be biased to the unactuated position, the clinician simply activates a closure release button assembly  518  which enables the closure trigger to return to unactuated position. The closure release button assembly  518  may also be configured to interact with various sensors that communicate with a microprocessor  560  in the handle assembly  500  for tracking the position of the closure trigger  512 . Further details concerning the configuration and operation of the closure release button assembly  518  may be found in U.S. Patent Application Publication No. 2015/0272575, now U.S. Pat. No. 9,913,642. 
     In at least one form, the handle assembly  500  and the handle frame  506  may operably support another drive system referred to herein as a firing drive system  530  that is configured to apply firing motions to corresponding portions of the interchangeable surgical tool assembly that is attached thereto. As was described in detail in U.S. Patent Application Publication No. 2015/0272575, now U.S. Pat. No. 9,913,642, the firing drive system  530  may employ an electric motor  505  that is located in the pistol grip portion  504  of the handle assembly  500 . In various forms, the motor  505  may be a DC brushed driving motor having a maximum rotation of, approximately, 25,000 RPM, for example. In other arrangements, the motor  505  may include a brushless motor, a cordless motor, a synchronous motor, a stepper motor, or any other suitable electric motor. The motor  505  may be powered by a power source  522  that in one form may comprise a removable power pack. The power pack may support a plurality of Lithium Ion (“LI”) or other suitable batteries therein. A number of batteries connected in series may be used as the power source  522  for the surgical system  10 . In addition, the power source  522  may be replaceable and/or rechargeable. 
     The electric motor  505  is configured to axially drive a longitudinally movable drive member (not shown) in a distal and proximal directions depending upon the polarity of the motor. For example, when the motor is driven in one rotary direction, the longitudinally movable drive member will be axially driven in a distal direction “DD”. When the motor  505  is driven in the opposite rotary direction, the longitudinally movable drive member will be axially driven in a proximal direction “PD”. The handle assembly  500  can include a switch  513  which can be configured to reverse the polarity applied to the electric motor  505  by the power source  522  or otherwise control the motor  505 . The handle assembly  500  can also include a sensor or sensors (not shown) that is configured to detect the position of the drive member and/or the direction in which the drive member is being moved. Actuation of the motor  505  can be controlled by a firing trigger  532  ( FIG.  1   ) that is pivotally supported on the handle assembly  500 . The firing trigger  532  may be pivoted between an unactuated position and an actuated position. The firing trigger  532  may be biased into the unactuated position by a spring or other biasing arrangement such that when the clinician releases the firing trigger  532 , it may be pivoted or otherwise returned to the unactuated position by the spring or biasing arrangement. In at least one form, the firing trigger  532  can be positioned “outboard” of the closure trigger  512  as was discussed above. As discussed in U.S. Patent Application Publication No. 2015/0272575, now U.S. Pat. No. 9,913,642, the handle assembly  500  may be equipped with a firing trigger safety button (not shown) to prevent inadvertent actuation of the firing trigger  532 . When the closure trigger  512  is in the unactuated position, the safety button is contained in the handle assembly  500  where the clinician cannot readily access it and move it between a safety position preventing actuation of the firing trigger  532  and a firing position wherein the firing trigger  532  may be fired. As the clinician depresses the closure trigger  512 , the safety button and the firing trigger  532  pivot down wherein they can then be manipulated by the clinician. 
     In at least one form, the longitudinally movable drive member may have a rack of teeth (not shown) formed thereon for meshing engagement with a corresponding drive gear arrangement (not shown) that interfaces with the motor. Further details regarding those features may be found in U.S. Patent Application Publication No. 2015/0272575, now U.S. Pat. No. 9,913,642. At least one form also includes a manually-actuatable “bailout” assembly that is configured to enable the clinician to manually retract the longitudinally movable drive member should the motor  505  become disabled. The bailout assembly may include a lever or bailout handle assembly that is stored within the handle assembly  500  under a releasable door  550 . See  FIG.  2   . The lever may be configured to be manually pivoted into ratcheting engagement with the teeth in the drive member. Thus, the clinician can manually retract the drive member by using the bailout handle assembly to ratchet the drive member in the proximal direction “PD”. U.S. Pat. No. 8,608,045, entitled POWERED SURGICAL CUTTING AND STAPLING APPARATUS WITH MANUALLY RETRACTABLE FIRING SYSTEM, the entire disclosure of which is hereby incorporated by reference herein, discloses bailout arrangements and other components, arrangements and systems that may also be employed with any one of the various interchangeable surgical tool assemblies disclosed herein. 
     Turning now to  FIGS.  3  and  4   , the interchangeable surgical tool assembly  1000  includes a surgical end effector  1500  that comprises a first jaw  1600  and a second jaw  1800 . In one arrangement, the first jaw comprises an elongate channel  1602  that is configured to operably support a surgical staple/fastener cartridge  1700  therein. The second jaw  1800  comprises an anvil  1810  that is pivotally supported relative to the elongate channel  1602 . The interchangeable surgical tool assembly  1000  includes an articulation system  1300  that comprises an articulation joint  1302  and an articulation lock  1400  ( FIGS.  4 - 6   ) which can be configured to releasably hold the surgical end effector  1500  in a desired articulated position relative to a shaft axis SA 1 . Further details regarding the articulation system and articulation lock may be found in U.S. patent application Ser. No. 15/635,837, entitled SURGICAL INSTRUMENT COMPRISING AN ARTICULATION SYSTEM LOCKABLE TO A FRAME, filed on Jun. 28, 2017, now U.S. Patent Application Publication No. 2019/0000472, and hereby incorporated by reference herein in its entirety. 
     As can be further seen in  FIGS.  4  and  7 - 9   , the interchangeable surgical tool assembly  1000  includes a tool frame assembly  1200  that comprises a tool chassis  1210  that operably supports a nozzle assembly  1240  thereon. In one form, the nozzle assembly  1240  is comprised of nozzle portions  1242 ,  1244  as well as an actuator wheel portion  1246  that is configured to be coupled to the assembled nozzle portions  1242 ,  1244  by snaps, lugs, screws etc. The interchangeable surgical tool assembly  1000  includes a proximal closure assembly  1900  which is operably coupled to a distal closure assembly  2000  that is utilized to close and/or open the anvil  1810  of the surgical end effector  1500  as will be discussed in further detail below. In addition, the interchangeable surgical tool assembly  1000  includes a spine assembly  1250  that operably supports the proximal closure assembly  1900  and is coupled to the surgical end effector  1500 . In various circumstances, for ease of assembly, the spine assembly  1250  may be fabricated from an upper spine segment  1251  and a lower spine segment  1252  that are interconnected together by snap features, adhesive, welding, etc. In assembled form, the spine assembly  1250  includes a proximal end  1253  that is rotatably supported in the tool chassis  1210 . In one arrangement, for example, the proximal end  1253  of the spine assembly  1250  is attached to a spine bearing (not shown) that is configured to be supported within the tool chassis  1210 . Such arrangement facilitates rotatable attachment of the spine assembly  1250  to the tool chassis  1210  such that the spine assembly  1250  may be selectively rotated about the shaft axis SA 1  relative to the tool chassis  1210 . In particular, in one arrangement, for example, the proximal end  1253  of the spine assembly  1250  includes an upper lug seat  1254  ( FIGS.  4 ,  5 ,  7 ,  8  and  10   ) and a lower lug seat (not shown) that are each configured to receive a corresponding nozzle lug  1245  extending inwardly from each of the nozzle portions  1242 ,  1244 . Such arrangement facilitates rotation of the spine assembly  1250  about the shaft axis SA 1  by rotating the actuator wheel portion  1246  of the nozzle assembly  1240 . 
     As can be seen in  FIGS.  4  and  5   , spine assembly  1250  further includes an intermediate spine shaft segment  1256  that has a diameter that is less than the diameter of the proximal end  1253  of the spine assembly  1250 . The intermediate spine shaft segment  1256  of the upper spine segment  1251  terminates in an upper lug mount feature  1260  and the intermediate spine shaft segment of the lower spine segment  1252  terminates in a lower lug mount feature  1270 . As can be most particularly seen in  FIG.  6   , for example, the upper lug mount feature  1260  is formed with a lug slot  1262  therein that is adapted to mountingly support an upper mounting link  1264  therein. Similarly, the lower lug mount feature  1270  is formed with a lug slot  1272  therein that is adapted to mountingly support a lower mounting link  1274  therein. The upper mounting link  1264  includes a pivot socket  1266  therein that is offset from the shaft axis SA 1 . The pivot socket  1266  is adapted to rotatably receive therein a pivot pin  1634  that is formed on a channel cap or anvil retainer  1630  that is attached to a proximal end portion  1610  of the elongate channel  1602 . The lower mounting link  1274  includes lower pivot pin  1276  that adapted to be received within a pivot hole  1611  formed in the proximal end portion  1610  of the elongate channel  1602 . See  FIG.  6   . The lower pivot pin  1276  as well as the pivot hole  1611  is offset from the shaft axis SA 1 . The lower pivot pin  1276  is vertically aligned with the pivot socket  1266  to define an articulation axis AA 1  about which the surgical end effector  1500  may articulate relative to the shaft axis SA 1 . Although the articulation axis AA 1  is transverse to the shaft axis SA 1 , the articulation axis AA 1  is laterally offset therefrom and does not intersect the shaft axis SA 1 . 
     Referring now to  FIGS.  6  and  15   , the anvil  1810  in the illustrated example includes an anvil body  1812  that terminates in anvil mounting portion  1820 . The anvil mounting portion  1820  is movably or pivotably supported on the elongate channel  1602  for selective pivotal travel relative thereto about a fixed anvil pivot axis PA 1  ( FIG.  15   ) that is transverse to the shaft axis SA 1 . In the illustrated arrangement, a pivot member or anvil trunnion  1822  extends laterally out of each lateral side of the anvil mounting portion  1820  to be received in a corresponding trunnion cradle  1614  formed in the upstanding walls  1612  of the proximal end portion  1610  of the elongate channel  1602 . The anvil trunnions  1822  are pivotally retained in their corresponding trunnion cradle  1614  by the channel cap or anvil retainer  1630 . The channel cap or anvil retainer  1630  includes a pair of attachment lugs  1636  that are configured to be retainingly received within corresponding lug grooves or notches  1616  formed in the upstanding walls  1612  of the proximal end portion  1610  of the elongate channel  1602 . 
     In the illustrated example, the surgical end effector  1500  is selectively articulatable about the articulation axis AA 1  by the articulation system  1300 . In one form, the articulation system  1300  includes proximal articulation driver  1310  that is pivotally coupled to an articulation link  1320 . As can be most particularly seen in  FIG.  6   , an offset attachment lug  1314  is formed on a distal end  1312  of the proximal articulation driver  1310 . A pivot hole  1316  is formed in the offset attachment lug  1314  and is configured to pivotally receive therein a proximal link pin  1326  formed on the proximal end  1325  of the articulation link  1320 . A distal end  1322  of the articulation link  1320  includes a pivot hole  1324  that is configured to pivotally receive therein a channel pin  1618  formed on the proximal end portion  1610  of the elongate channel  1602 . Thus, axial movement of proximal articulation driver  1310  will thereby apply articulation motions to the elongate channel  1602  to thereby cause the surgical end effector  1500  to articulate about the articulation axis AA 1  relative to the spine assembly  1250 . 
     Movement of the anvil  1810  relative to the elongate channel  1602  is effectuated by axial movement of the proximal closure assembly  1900  and the distal closure assembly  2000 . Referring now to  FIGS.  4  and  7   , in the illustrated arrangement, the proximal closure assembly  1900  comprises a proximal closure tube  1910  that has a proximal closure tube portion  1920  and a distal portion  1930 . The distal portion  1930  has a diameter that is less than the diameter of the proximal closure tube portion  1920 . The proximal end  1922  of the proximal closure tube portion  1920  is rotatably supported in a closure shuttle  1940  that is slidably supported within the tool chassis  1210  such that it may be axially moved relative thereto. In one form, the closure shuttle  1940  includes a pair of proximally-protruding hooks  1942  that are configured for attachment to the attachment pin  516  that is attached to the closure linkage assembly  514  of the handle assembly  500 . The proximal end  1922  of the proximal closure tube portion  1920  is coupled to the closure shuttle  1940  for relative rotation thereto. For example, a U-shaped connector  1944  is inserted into an annular slot  1924  in the proximal closure tube portion  1920  and is retained within vertical slots  1946  in the closure shuttle  1940 . Such arrangement serves to attach the proximal closure assembly  1900  to the closure shuttle  1940  for axial travel therewith while enabling the proximal closure assembly  1900  to rotate relative to the closure shuttle  1940  about the shaft axis SA 1 . A closure spring  1948  ( FIGS.  12 - 14   ) extends over the proximal closure tube portion  1920  to bias the closure shuttle  1940  in the proximal direction PD which can serve to pivot the closure trigger  512  on the handle assembly  500  ( FIG.  2   ) into the unactuated position when the interchangeable surgical tool assembly  1000  is operably coupled to the handle assembly  500 . 
     Referring now to  FIGS.  5  and  6   , a distal portion  1930  of the proximal closure tube  1910  is attached to the distal closure assembly  2000 . In the illustrated arrangement for example, the distal closure assembly  2000  includes an articulation connector  2010  that is coupled to a distal closure tube segment  2030 . In the illustrated example, the distal closure tube segment  2030  has a diameter that is larger than the diameter of the distal portion  1930  of the proximal closure tube  1910 . The articulation connector  2010  has a proximally extending end portion  2012  that is adapted to be received on a connection flange  1934  formed on the distal end of the distal portion  1930 . The articulation connector  2010  may be retained on the connection flange  1934  by an appropriate fastener arrangement such as adhesive, welding, etc. The articulation connector  2010  includes upper and lower tangs  2014 ,  2016  protrude distally from a distal end of the articulation connector  2010  to be movably coupled to an end effector closure sleeve or distal closure tube segment  2030 . The distal closure tube segment  2030  includes an upper tang  2032  and a lower tang (not shown) that protrude proximally from a proximal end thereof. An upper double pivot link  2060  includes proximal and distal pins  2061 ,  2062  that engage corresponding holes  2015 ,  2034  in the upper tangs  2014 ,  2032  of the articulation connector  2010  and distal closure tube segment  2030 , respectively. Similarly, a lower double pivot link  2064  includes proximal and distal pins  2065 ,  2066  that engage corresponding holes  2019  in the lower tangs  2016  of the articulation connector  2010  and distal closure tube segment  2030 , respectively. As will be discussed in further detail below, distal and proximal axial translation of the proximal closure assembly  1900  and distal closure assembly  2000  will result in the closing and opening of the anvil  1810  relative to the elongate channel  1602 . 
     In at least one arrangement, the interchangeable surgical tool assembly  1000  further includes a firing system generally designated as  2100 . In the illustrated example, the firing system  2100  includes a firing member assembly  2110  that is supported for axial travel within the spine assembly  1250 . In the illustrated embodiment, the firing member assembly  2110  includes an intermediate firing shaft portion  2120  that is configured for attachment to a distal cutting portion or knife bar  2130 . The firing member assembly  2110  may also be referred to herein as a “second shaft” and/or a “second shaft assembly”. As can be seen in  FIG.  5   , the intermediate firing shaft portion  2120  may include a longitudinal slot  2124  in a distal end  2122  thereof which can be configured to receive a proximal end  2132  of the knife bar  2130 . The longitudinal slot  2124  and the proximal end  2132  of the knife bar  2130  can be sized and configured to permit relative movement therebetween and can comprise a slip joint  2134 . The slip joint  2134  can permit the intermediate firing shaft portion  2120  of the firing member assembly  2110  to be moved to articulate the end effector  1500  without moving, or at least substantially moving, the knife bar  2130 . Once the end effector  1500  has been suitably oriented, the intermediate firing shaft portion  2120  can be advanced distally until a proximal sidewall of the longitudinal slot  2124  comes into contact with a portion of the knife bar  2130  to advance the knife bar  2130  and fire the surgical staple/fastener cartridge  1700  positioned within the elongate channel  1602 . In the illustrated arrangement, a proximal end  2127  of the intermediate firing shaft portion  2120  has a firing shaft attachment lug  2128  formed thereon ( FIG.  8   ) that is configured to be seated into an attachment cradle (not shown) that is on the distal end of the longitudinally movable drive member (not shown) of the firing drive system  530  within the handle assembly  500 . Such arrangement facilitates the axial movement of the intermediate firing shaft portion  2120  upon actuation of the firing drive system  530 . 
     Further to the above, the interchangeable tool assembly  1000  can include a shifter assembly  2200  which can be configured to selectively and releasably couple the proximal articulation driver  1310  to the firing system  2100 . In one form, the shifter assembly  2200  includes a lock collar, or lock sleeve  2210 , positioned around the intermediate firing shaft portion  2120  of the firing system  2100  wherein the lock sleeve  2210  can be rotated between an engaged position in which the lock sleeve  2210  couples the proximal articulation driver  1310  to the firing member assembly  2110  and a disengaged position in which the proximal articulation driver  1310  is not operably coupled to the firing member assembly  2110 . When lock sleeve  2210  is in its engaged position, distal movement of the firing member assembly  2110  can move the proximal articulation driver  1310  distally and, correspondingly, proximal movement of the firing member assembly  2110  can move the proximal articulation driver  1310  proximally. When lock sleeve  2210  is in its disengaged position, movement of the firing member assembly  2110  is not transmitted to the proximal articulation driver  1310  and, as a result, the firing member assembly  2110  can move independently of the proximal articulation driver  1310 . In various circumstances, the proximal articulation driver  1310  can be held in position by the articulation lock  1400  when the proximal articulation driver  1310  is not being moved in the proximal or distal directions by the firing member assembly  2110 . 
     In the illustrated arrangement, the intermediate firing shaft portion  2120  of the firing member assembly  2110  is formed with two opposed flat sides  2121 ,  2123  with a drive notch  2126  formed therein. See  FIG.  8   . As can also be seen in  FIG.  13   , the lock sleeve  2210  comprises a cylindrical, or an at least substantially cylindrical, body that includes a longitudinal aperture  2212  that is configured to receive the intermediate firing shaft portion  2120  therethrough. The lock sleeve  2210  can comprise diametrically-opposed, inwardly-facing lock protrusions  2214 ,  2216  that, when the lock sleeve  2210  is in one position, are engagingly received within corresponding portions of the drive notch  2126  in the intermediate firing shaft portion  2120  and, when in another position, are not received within the drive notch  2126  to thereby permit relative axial motion between the lock sleeve  2210  and the intermediate firing shaft portion  2120 . 
     Referring now to  FIGS.  8  and  12 - 14   , in the illustrated example, the lock sleeve  2210  further includes a lock member  2218  that is sized to be movably received within a notch  1319  in a proximal end  1318  of the proximal articulation driver  1310 . Such arrangement permits the lock sleeve  2210  to slightly rotate into and out of engagement with the intermediate firing shaft portion  2120  while remaining in engagement with the notch  1319  in the proximal articulation driver  1310 . For example, when the lock sleeve  2210  is in its engaged position, the lock protrusions  2214 ,  2216  are positioned within the drive notch  2126  in the intermediate firing shaft portion  2120  such that a distal pushing force and/or a proximal pulling force can be transmitted from the firing member assembly  2110  to the lock sleeve  2210 . Such axial pushing or pulling motion is then transmitted from the lock sleeve  2210  to the proximal articulation driver  1310  to thereby articulate the surgical end effector  1500 . In effect, the firing member assembly  2110 , the lock sleeve  2210 , and the proximal articulation driver  1310  will move together when the lock sleeve  2210  is in its engaged (articulation) position. On the other hand, when the lock sleeve  2210  is in its disengaged position, the lock protrusions  2214 ,  2216  are not received within the drive notch  2126  in the intermediate firing shaft portion  2120  and, as a result, a distal pushing force and/or a proximal pulling force may not be transmitted from the firing member assembly  2110  to the lock sleeve  2210  (and the proximal articulation driver  1310 ). 
     In the illustrated example, relative movement of the lock sleeve  2210  between its engaged and disengaged positions may be controlled by a shifter assembly  2200  that is interfaces with the proximal closure tube  1910  of the proximal closure assembly  1900 . More specifically and with reference to  FIGS.  8  and  9   , the shifter assembly  2200  further includes a shifter key  2240  that is configured to be slidably received within a key groove  2217  formed in the outer perimeter of the lock sleeve  2210 . Such arrangement enables the shifter key  2240  to move axially with respect to the lock sleeve  2210 . Referring to  FIGS.  8 - 11   , the shifter key  2240  includes an actuator lug  2242  that extends through a cam slot or cam opening  1926  in the proximal closure tube portion  1920 . See  FIG.  9   . A cam surface  2243  is also provided adjacent the actuator lug  2242  which is configured to cammingly interact with the cam opening  1926  so as to cause the shifter key  2240  to rotate in response to axial motion of the proximal closure tube portion  1920 . 
     Also in the illustrated example, the shifter assembly  2200  further includes a switch drum  2220  that is rotatably received on a proximal end portion of the proximal closure tube portion  1920 . As can be seen in  FIGS.  10 - 14   , the actuator lug  2242  extends through an axial slot segment  2222  in the switch drum  2220  and is movably received within an arcuate slot segment  2224  in the switch drum  2220 . A switch drum torsion spring  2226  ( FIGS.  12 - 14   ) is mounted on the switch drum  2220  and engages nozzle portion  1244  to apply a torsional bias or rotation (arrow SR in  FIGS.  10  and  11   ) which serves to rotate the switch drum  2220  until the actuator lug  2242  reaches the end of the arcuate slot segment  2224 . See  FIGS.  11  and  12   . When in this position, the switch drum  2220  may provide a torsional bias to the shifter key  2240  which thereby causes the lock sleeve  2210  to rotate into its engaged position with the intermediate firing shaft portion  2120 . This position also corresponds to the unactuated configuration of the proximal closure assembly  1900 . In one arrangement, for example, when the proximal closure assembly  1900  is in an unactuated configuration (anvil  1810  is in an open position spaced away from the surgical staple/fastener cartridge  1700 ) the actuator lug  2242  is located in the upper portion of the cam opening  1926  in the proximal closure tube portion  1920 . When in that position, actuation of the intermediate firing shaft portion  2120  will result in the axial movement of the proximal articulation driver  1310 . Once the user has articulated the surgical end effector  1500  to a desired orientation, the user may then actuate the proximal closure assembly  1900 . Actuation of the proximal closure assembly  1900  will result in the distal travel of the proximal closure tube portion  1920  to ultimately apply a closing motion to the anvil  1810 . This distal travel of the proximal closure tube portion  1920  will result in the cam opening  1926  cammingly interacting with the cam surface  2243  on the actuator lug  2242  to thereby cause the shifter key  2240  to rotate the lock sleeve  2210  in an actuation direction AD. Such rotation of the lock sleeve  2210  will result in the disengagement of the lock protrusions  2214 ,  2216  from the drive notch  2126  in the intermediate firing shaft portion  2120 . When in such configuration, the firing drive system  530  may be actuated to actuate the intermediate firing shaft portion  2120  without actuating the proximal articulation driver  1310 . Further details concerning the operation of the switch drum  2220  and lock sleeve  2210 , as well as alternative articulation and firing drive arrangements that may be employed with the various interchangeable surgical tool assemblies described herein, may be found in U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541, and U.S. patent application Ser. No. 15/019,196, now U.S. Pat. No. 10,413,291, the entire disclosures of which are hereby incorporated by reference herein. 
     Referring again to  FIGS.  8 - 13   , the switch drum  2220  can further comprise at least partially circumferential openings  2228 ,  2230  defined therein which can receive circumferential lugs/mounts  1245  that extend from the nozzle portions  1242 ,  1244  and permit relative rotation, but not translation, between the switch drum  2220  and the nozzle assembly  1240 . The nozzle lugs  1245  extend through corresponding openings  1923  in the proximal closure tube portion  1920  to be seated in lug seats  1254  in the spine assembly  1250 . See  FIGS.  8  and  9   . Such arrangement enables the user to rotate the spine assembly  1250  about the shaft axis by rotating the nozzle assembly  1240 . 
     As also illustrated in  FIGS.  7  and  12 - 14   , the interchangeable tool assembly  1000  can comprise a slip ring assembly  1230  which can be configured to conduct electrical power to and/or from the surgical end effector  1500  and/or communicate signals to and/or from the surgical end effector  1500 , back to a microprocessor  560  ( FIG.  2   ) in the handle assembly  500  or robotic system controller, for example. Further details concerning the slip ring assembly  1230  and associated connectors may be found in U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541, and U.S. patent application Ser. No. 15/019,196, now U.S. Pat. No. 10,413,291, which have each been herein incorporated by reference in their respective entirety as well as in U.S. patent application Ser. No. 13/800,067, entitled STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, now U.S. Patent Application Publication No. 2014/0263552, which is hereby incorporated by reference herein in its entirety. As also described in further detail in the aforementioned patent applications that have been incorporated by reference herein, the interchangeable surgical tool assembly  1000  can also comprise at least one sensor that is configured to detect the position of the switch drum  2220 . 
     Referring again to  FIG.  2   , the tool chassis  1210  includes at least one, and preferably two, tapered attachment portions  1212  formed thereon that are adapted to be received within corresponding dovetail slots  507  formed within the distal end portion of the handle frame  506  of the handle assembly  500 . Various interchangeable surgical tool assemblies employ a latch system  1220  for removably coupling the interchangeable surgical tool assembly  1000  to the handle frame  506  of the handle assembly  500 . As can be seen in  FIG.  7   , for example, in at least one form, the latch system  1220  includes a lock member or lock yoke  1222  that is movably coupled to the tool chassis  1210 . In the illustrated embodiment, for example, the lock yoke  1222  has a U-shape with two spaced downwardly extending legs  1223 . The legs  1223  each have a pivot lug (not shown) formed thereon that are adapted to be received in corresponding holes formed in the tool chassis  1210 . Such arrangement facilitates pivotal attachment of the lock yoke  1222  to the tool chassis  1210 . The lock yoke  1222  may include two proximally protruding lock lugs  1224  that are configured for releasable engagement with corresponding lock detents or grooves  509  in the distal end of the handle frame  506  of the handle assembly  500 . See  FIG.  2   . In various forms, the lock yoke  1222  is biased in the proximal direction by a spring or biasing member  1225 . Actuation of the lock yoke  1222  may be accomplished by a latch button  1226  that is slidably mounted on a latch actuator assembly  1221  that is mounted to the tool chassis  1210 . The latch button  1226  may be biased in a proximal direction relative to the lock yoke  1222 . The lock yoke  1222  may be moved to an unlocked position by biasing the latch button  1226  in the distal direction which also causes the lock yoke  1222  to pivot out of retaining engagement with the distal end of the handle frame  506 . When the lock yoke  1222  is in “retaining engagement” with the distal end of the handle frame  506 , the lock lugs  1224  are retainingly seated within the corresponding lock detents or grooves  509  in the distal end of the handle frame  506 . 
     In the illustrated arrangement, the lock yoke  1222  includes at least one and preferably two lock hooks  1227  that are adapted to contact corresponding lock lug portions  1943  that are formed on the closure shuttle  1940 . When the closure shuttle  1940  is in an unactuated position, the lock yoke  1222  may be pivoted in a distal direction to unlock the interchangeable surgical tool assembly  1000  from the handle assembly  500 . When in that position, the lock hooks  1227  do not contact the lock lug portions  1943  on the closure shuttle  1940 . However, when the closure shuttle  1940  is moved to an actuated position, the lock yoke  1222  is prevented from being pivoted to an unlocked position. Stated another way, if the clinician were to attempt to pivot the lock yoke  1222  to an unlocked position or, for example, the lock yoke  1222  was inadvertently bumped or contacted in a manner that might otherwise cause it to pivot distally, the lock hooks  1227  on the lock yoke  1222  will contact the lock lug portions  1943  on the closure shuttle  1940  and prevent movement of the lock yoke  1222  to an unlocked position. 
     Referring again to  FIG.  6   , the knife bar  2130  may comprise a laminated beam structure that includes at least two beam layers. Such beam layers may comprise, for example, stainless steel bands that are interconnected by, for example, welding or pinning together at their proximal ends and/or at other locations along their length. In alternative embodiments, the distal ends of the bands are not connected together to allow the laminates or bands to splay relative to each other when the end effector is articulated. Such arrangement permits the knife bar  2130  to be sufficiently flexible to accommodate articulation of the end effector. Various laminated knife bar arrangements are disclosed in U.S. patent application Ser. No. 15/019,245, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, which is hereby incorporated by reference in its entirety. As can also be seen in  FIG.  6   , a firing shaft support assembly  2300  is employed to provide lateral support to the knife bar  2130  as it flexes to accommodate articulation of the surgical end effector  1500 . Further details concerning the operation of the firing shaft support assembly  2300  and alternative knife bar support arrangements may be found in U.S. patent application Ser. No. 15/019,245, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, and U.S. patent application Ser. No. 15/019,220, entitled SURGICAL INSTRUMENT WITH ARTICULATING AND AXIALLY TRANSLATABLE END EFFECTOR, now U.S. Pat. No. 10,245,029, which are each hereby incorporated by reference herein in their respective entireties. 
     As can also be seen in  FIG.  6   , a firing member or knife member  2140  is attached to the distal end of the knife bar  2130 . In one exemplary form, the firing member  2140  comprises a body portion  2142  that supports a knife or tissue cutting portion  2144 . The body portion  2142  protrudes through an elongate slot  1604  in the elongate channel  1602  and terminates in a foot member  2146  that extends laterally on each side of the body portion  2142 . As the firing member  2140  is driven distally through the surgical staple/fastener cartridge  1700 , the foot member  2146  rides within a passage  1622  ( FIG.  48   ) in the elongate channel  1602  that is located under the surgical staple/fastener cartridge  1700 . In one arrangement, the body portion  2142  includes two laterally protruding central tabs  2145  that may ride above the central passage within the surgical staple/fastener cartridge  1700 . See  FIG.  6   . The tissue cutting portion  2144  is disposed between a distally protruding top nose portion  2143 . As can be further seen in  FIG.  6   , the firing member  2140  may further include two laterally extending top tabs, pins or anvil engagement features  2147 . As the firing member  2140  is driven distally, a top portion of the body portion  2142  extends through a centrally disposed anvil slot  1814  and the anvil engagement features  2147  ride on corresponding anvil ledges  1816  formed on each side of the anvil slot  1814 . In one arrangement, to facilitate assembly of the anvil  1810  and firing member  2140  arrangement, the top of the anvil body  1812  has an opening  1817  therein. Once the anvil  1810  is assembled onto the elongate channel  1602  and the firing member  2140  is installed, the opening  1817  is covered by an anvil cap  1819  that is affixed to the anvil body  1812  by welding or other suitable fastening means. 
     Returning to  FIG.  6   , the firing member  2140  is configured to operably interface with a sled assembly  2150  that is operably supported within a body  1702  of the surgical staple/fastener cartridge  1700 . The sled assembly  2150  is slidably displaceable within the surgical staple/fastener cartridge body  1702  from a proximal starting position adjacent the proximal end  1704  of the cartridge body  1702  to an ending position adjacent a distal end  1706  of the cartridge body  1702 . The cartridge body  1702  operably supports therein a plurality of staple drivers (not shown) that are aligned in rows on each side of a centrally disposed slot  1708 . The centrally disposed slot  1708  enables the firing member  2140  to pass therethrough and cut the tissue that is clamped between the anvil  1810  and the surgical staple/fastener cartridge  1700 . The drivers are associated with corresponding staple/fastener pockets  1712  that open through an upper deck surface  1710  of the cartridge body  1702 . Each of the staple drivers supports one or more surgical staple/fastener or fastener (not shown) thereon. The sled assembly  2150  includes a plurality of sloped or wedge-shaped cams  2152  wherein each cam  2152  corresponds to a particular line of fasteners or drivers located on a side of the slot  1708 . 
     Attachment of the interchangeable surgical tool assembly  1000  to the handle assembly  500  will now be described with reference to  FIG.  2   . To commence the coupling process, the clinician may position the tool chassis  1210  of the interchangeable surgical tool assembly  1000  above or adjacent to the distal end of the handle frame  506  such that the tapered attachment portions  1212  formed on the tool chassis  1210  are aligned with the dovetail slots  507  in the handle frame  506 . The clinician may then move the surgical tool assembly  1000  along an installation axis IA that is perpendicular to the shaft axis SA 1  to seat the tapered attachment portions  1212  in “operable engagement” with the corresponding dovetail receiving slots  507  in the distal end of the handle frame  506 . In doing so, the firing shaft attachment lug  2128  on the intermediate firing shaft portion  2120  will also be seated in the attachment cradle (not shown) in the longitudinally movable drive member (not shown) within the handle assembly  500  and the portions of attachment pin  516  on the closure link  514  will be seated in the corresponding hooks  1942  in the closure shuttle  1940 . As used herein, the term “operable engagement” in the context of two components means that the two components are sufficiently engaged with each other so that upon application of an actuation motion thereto, the components may carry out their intended action, function and/or procedure. 
     During a typical surgical procedure, the clinician may introduce the surgical end effector  1500  into the surgical site through a trocar or other opening in the patient to access the target tissue. When doing so, the clinician typically axially aligns the surgical end effector  1500  along the shaft axis (unarticulated state). Once the surgical end effector  1500  has passed through the trocar port, for example, the clinician may need to articulate the end effector  1500  to advantageously position it adjacent the target tissue. This is prior to closing the anvil onto the target tissue, so the closure drive system  510  would remain unactuated. When in this position, actuation of the firing drive system  530  will result in the application of articulation motions to the proximal articulation driver  1310 . Once the end effector has attained the desired articulated position, the firing drive system  530  is deactivated and the articulation lock  1400  may retain the surgical end effector  1500  in the articulated position. The clinician may then actuate the closure drive system  510  to close the anvil  1810  onto the target tissue. Such actuation of the closure drive system  510  may also result in the shifter assembly  2200  delinking the proximal articulation driver from the intermediate firing shaft portion  2120 . Thus, once the target tissue has been captured in the surgical end effector  1500 , the clinician may once again actuate the firing drive system  530  to axially advance the firing member  2140  through the surgical staple/fastener cartridge  1700  to cut the clamped tissue and fire the staples into the cut tissue. Other closure and firing drive arrangements, actuator arrangements (both handheld, manual and automated or robotic) may also be employed to control the axial movement of the closure system components, the articulation system components and/or the firing system components of the surgical tool assembly  1000  without departing from the spirit and scope of the various inventions disclosed herein. 
     Returning now to  FIG.  1   , the surgical system  10  illustrated in that Figure includes four interchangeable surgical tool assemblies  1000 ,  3000 ,  5000  and  7000  that may each be effectively employed with the same handle assembly  500  to perform different surgical procedures. Turning now to  FIGS.  16 - 18   , the interchangeable surgical tool assembly  3000  includes a surgical end effector  3500  that comprises a first jaw  3600  and a second jaw  3800 . In one arrangement, the first jaw comprises an elongate channel  3602  that is configured to operably support a surgical staple/fastener cartridge  3700  therein. The second jaw  3800  comprises an anvil  3810  that is pivotally supported relative to the elongate channel  3602 . The interchangeable surgical tool assembly  3000  includes an articulation system  3300  that comprises an articulation joint  3302  and an articulation lock  3400  which can be configured to releasably hold the surgical end effector  3500  in a desired articulated position relative to a shaft axis SA 2 . Details regarding the construction and operation of the articulation lock  3400  as well as alternative lock configurations and operational details may be found in in U.S. patent application Ser. No. 13/803,086, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. Patent Application Publication No. 2014/0263541, the entire disclosure of which is hereby incorporated by reference herein. Additional details concerning the articulation lock  3400  may also be found in U.S. patent application Ser. No. 15/019,196, filed Feb. 9, 2016, entitled SURGICAL INSTRUMENT ARTICULATION MECHANISM WITH SLOTTED SECONDARY CONSTRAINT, now U.S. Pat. No. 10,413,291, the entire disclosure of which is hereby incorporated by reference herein. 
     As can be seen in  FIG.  17   , the interchangeable surgical tool assembly  3000  includes a tool frame assembly  3200  that comprises a tool chassis  3210  that operably supports a nozzle assembly  3240  thereon. In one form, the nozzle assembly  3240  is comprised of nozzle portions  3242 ,  3244  as well as an actuator wheel portion  3246  that is configured to be coupled to the assembled nozzle portions  3242 ,  3244  by snaps, lugs, screws etc. The interchangeable surgical tool assembly  3000  includes a proximal closure assembly  3900  which is operably coupled to a distal closure assembly  4000  that is utilized to close and/or open the anvil  3810  of the surgical end effector  3500  as will be discussed in further detail below. In addition, the interchangeable surgical tool assembly  3000  includes an “elastic” spine assembly  3250  that operably supports the proximal closure assembly  3900  and is coupled to the surgical end effector  3500 . One exemplary form of spine assembly  3250  is disclosed in U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950, the entire disclosure of which is hereby incorporated by reference herein. For example, the spine assembly  3250  may comprise an elastic spine member that has a proximal end portion  3253  and a distal end portion  3280  that is separated from the proximal end portion  3253  of the elastic spine assembly  3250  by a stretch feature  3282  formed therebetween. In addition, a stretch limiting insert  3284  is retainingly supported between the distal end portion  3280  and the proximal end portion  3253 . In various arrangements, the elastic spine assembly  3250  may be fabricated from, for example, suitable polymeric material, rubber, etc. which has a modulus of elasticity designated as ME 1  for reference purposes. The stretch limiting insert  3284  may have a modulus of elasticity designated as ME 2  for reference purposes. In various circumstances, the stretch limiting insert  3284  also includes a pair of stretch limiters  3285  (only one is shown in  FIG.  17   ). The stretch limiter  3285  may have a modulus of elasticity for reference purposes of ME 3 . In at least one arrangement, ME 3 &lt;ME 2 &lt;ME 1 . Further details about at least one implementation of the elastic spine assembly  3250  and stretch limiting insert  3284  may be found in U.S. patent application Ser. No. 15/385,911, now U.S. Pat. No. 10,448,950. 
     In the illustrated arrangement, the distal end portion  3280  of the spine assembly  3250  has an opening  3281  therein for ease of assembly. A spine cap  3283  may be attached thereto to cover the opening  3281  after the various components have been assembled therein. In assembled form, the proximal end portion  3253  of the spine assembly  3250  is rotatably supported in the tool chassis  3210 . In one arrangement, for example, the proximal end of the proximal end portion  3253  of the spine assembly  3250  is attached to a spine bearing (not shown) that is configured to be supported within the tool chassis  3210 . Such arrangement facilitates rotatable attachment of the spine assembly  3250  to the tool chassis  3210  such that the spine assembly  3250  may be selectively rotated about a shaft axis SA 2  relative to the tool chassis  3210 . In particular, in one arrangement, for example, the proximal end portion  3253  of the spine assembly  3250  includes two diametrically opposed lug seats  3254  (only one can be seen in  FIG.  17   ) that are each configured to receive a corresponding nozzle lug (not shown) that extend inwardly from each of the nozzle portions  3242 ,  3244 . Such arrangement facilitates rotation of the spine assembly  3250  about the shaft axis SA 2  by rotating the actuator wheel portion  3246  of the nozzle assembly  3240 . 
     Referring now to  FIG.  18   , the distal end portion  3280  of the elastic spine assembly  3250  is attached to a distal frame segment  3286  that operably supports the articulation lock  3400  therein. The spine assembly  3250  is configured to, one, slidably support a firing member assembly  4110  therein and, two, slidably support the proximal closure tube  3910  which extends around the spine assembly  3250 . The spine assembly  3250  can also be configured to slidably support a proximal articulation driver  3310 . As can be seen in  FIG.  18   , the distal frame segment  3286  is pivotally coupled to the elongate channel  3602  by an end effector mounting assembly  3290 . In one arrangement, for example, the distal end of the distal frame segment  3286  has a pivot pin  3288  formed thereon. The pivot pin  3288  is adapted to be pivotally received within a pivot hole  3292  formed in pivot base portion  3291  of the end effector mounting assembly  3290 . The end effector mounting assembly  3290  is attached to a proximal end  3610  of the elongate channel  3602  by a spring pin  3620  or other suitable member that is received within mounting holes  3611  in the proximal end portion  3610 . The pivot pin  3288  defines an articulation axis AA 2  that is transverse to the shaft axis SA 2 . See  FIG.  18   . Such arrangement facilitates pivotal travel (i.e., articulation) of the surgical end effector  3500  about the articulation axis AA 2  relative to the elastic spine assembly  3250 . The distal frame segment  3286  is further configured to support the articulation lock  3400  therein. Various articulation lock arrangements may be employed. At least one form of articulation lock  3400  is described in further detail in U.S. patent application Ser. No. 13/803,086, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. Patent Application Publication No. 2014/0263541, the entire disclosure of which is hereby incorporated by reference herein. Additional details concerning the articulation lock may also be found in U.S. patent application Ser. No. 15/019,196, filed Feb. 9, 2016, entitled SURGICAL INSTRUMENT ARTICULATION MECHANISM WITH SLOTTED SECONDARY CONSTRAINT, now U.S. Pat. No. 10,413,291. 
     In the illustrated example, the surgical end effector  3500  is electively articulatable about the articulation axis AA 2  by the articulation system  3300 . In one form, the articulation system  3300  includes the proximal articulation driver  3310  that operably interfaces with the articulation lock  3400 . The articulation lock  3400  includes an articulation frame  3402  that is adapted to operably engage a drive pin  3293  on the pivot base portion  3291  of the end effector mounting assembly  3290 . In addition, a cross link  3294  may be linked to the drive pin  3293  and articulation frame  3402  to assist articulation of the surgical end effector  3500 . As indicated above, further details regarding the operation of the articulation lock  3400  and the articulation frame  3402  may be found in U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541. Further details regarding the end effector mounting assembly and cross link  3294  may be found in U.S. patent application Ser. No. 15/019,245, filed Feb. 9, 2016, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, the entire disclosure of which is hereby incorporated by reference herein. As further described therein, as well as in other disclosures incorporated by reference herein, axial movement of proximal articulation driver  3310  will result in the engagement/disengagement of the articulation lock  3400  to thereby apply articulation motions to the elongate channel  3602  and thereby cause the surgical end effector  3500  to articulate about the articulation axis AA 2  relative to the spine assembly  3250 . 
     The anvil  3810  in the illustrated example includes an anvil body  3812  that terminates in anvil mounting portion  3820 . The anvil mounting portion  3820  is movably or pivotably supported on the elongate channel  3602  for selective pivotal travel relative thereto about a fixed anvil pivot axis PA 2  ( FIG.  18   ) that is transverse to the shaft axis SA 2 . In the illustrated arrangement, an anvil trunnion  3822  extends laterally out of each lateral side of the anvil mounting portion  3820  to be received in a corresponding trunnion pivot hole  3613  formed in the upstanding walls  3612  of the proximal end portion  3610  of the elongate channel  3602 . Movement of the anvil  3810  relative to the elongate channel  3602  is effectuated by axial movement of the proximal closure assembly  3900  and the distal closure assembly  4000 . In the illustrated arrangement, the proximal closure assembly  3900  comprises a proximal closure tube  3910  that has a proximal end  3912  and a distal end  3914 . The proximal end  3912  is rotatably supported in a closure shuttle  3940  that is slidably supported within the tool chassis  3210  such that it may be axially moved relative thereto. In one form, the closure shuttle  3940  includes a pair of proximally-protruding hooks  3942  that are configured for attachment to the transverse attachment pin  516  that is attached to the closure linkage assembly  514  of the handle assembly  500 . The proximal end  3912  is coupled to the closure shuttle  3940  for relative rotation thereto. For example, a U-shaped connector  3944  is inserted into an annular slot  3916  in the proximal end  3912  and is retained within vertical slots  3946  in the closure shuttle  3940 . Such arrangement serves to attach the proximal closure assembly  3900  to the closure shuttle  3940  for axial travel therewith while enabling the proximal closure tube  3910  to rotate relative to the closure shuttle  3940  about the shaft axis SA 2 . As was discussed above in connection with the interchangeable surgical tool assembly  1000 , a closure spring (not shown) may extend over the proximal end  3912  of the proximal closure tube  3910  to bias the closure shuttle  3940  in the proximal direction PD which can serve to pivot the closure trigger  512  on the handle assembly  500  ( FIG.  2   ) into the unactuated position when the interchangeable surgical tool assembly  3000  is operably coupled to the handle assembly  500  in the above described manner. 
     As can be seen in  FIG.  18   , the distal end  3914  of the proximal closure tube  3910  is attached to the distal closure assembly  4000 . The distal end  3914  includes upper and lower tangs  3917 ,  3918  that are configured to be movably coupled to an end effector closure sleeve or distal closure tube segment  4030 . The distal closure tube segment  4030  includes an upper tang  4032  and a lower tang  4034  that protrude proximally from a proximal end thereof. An upper double pivot link  4060  pivotally couples the upper tangs  3917  and  4032  and a lower double pivot link  4064  pivotally couples the lower tangs  3918  and  4034  together in the above-described manner. The distal advancement of the distal closure tube segment  4030  on the anvil mounting portion  3820  will result in closure or pivotal travel of the anvil  3810  towards the elongate channel  3602  about the fixed anvil pivot axis PA 2 . In the illustrated arrangement, the distal closure tube segment  4030  also includes positive jaw or anvil opening features  4040  that are configured to coact with surfaces or ramp portions on the anvil mounting portion  3820  so as to cause the anvil  3810  to pivot from a closed position to an open position as the distal closure tube segment  4030  is moved proximally back to a starting position. Other embodiments may not employ the positive jaw opening features, but may rely on springs or other biasing arrangements to bias the anvil to the open position when the distal closure tube segment has been retracted to its proximal-most starting position. Further details regarding configurations and operation of the anvil opening features may be found in for example, U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950. 
     In the illustrated arrangement, the interchangeable surgical tool assembly  3000  further includes a firing system generally designated as  4100 . In various instances, the firing system  4100  includes a firing member assembly  4110  that is supported for axial travel within the spine assembly  3250 . In the illustrated embodiment, the firing member assembly  4110  includes an intermediate firing shaft portion  4120  that is configured for attachment to a distal cutting portion or knife bar  4130 . A support bushing arrangement  4121  may be employed to support the intermediate firing shaft portion  4120  within the spine assembly  3250 . The firing member assembly  4110  may also be referred to herein as a “second shaft” and/or a “second shaft assembly”. As can be seen in  FIG.  18   , the intermediate firing shaft portion  4120  may include a longitudinal slot  4124  in a distal end  4122  thereof which can be configured to receive a proximal end  4132  of the knife bar  4130 . The longitudinal slot  4124  and the proximal end  4132  of the knife bar  4130  can be sized and configured to permit relative movement therebetween and can comprise a slip joint  4134 . The slip joint  4134  can permit the intermediate firing shaft portion  4120  of the firing member assembly  4110  to be moved to articulate the end effector  3500  without moving, or at least substantially moving, the knife bar  4130  as was discussed above. In the illustrated arrangement, a proximal end  4127  of the intermediate firing shaft portion  4120  has a firing shaft attachment lug  4128  formed thereon that is configured to be seated into the attachment cradle (not shown) that is on the distal end of the longitudinally movable drive member (not shown) of the firing drive system  530  within the handle assembly  500  as was discussed above. Such arrangement facilitates the axial movement of the intermediate firing shaft portion  4120  upon actuation of the firing drive system  530 . Other attachment configurations may also be employed to couple the intermediate firing shaft portion  4120  to other firing drive arrangements (e.g., manually actuated, robotic, etc.). 
     Further to the above, the interchangeable tool assembly  3000  can include a shifter assembly  4200  which can be configured to selectively and releasably couple the proximal articulation driver  3310  to the firing member assembly  4110  in the manner described above. In one form, the shifter assembly  4200  includes a lock collar, or lock sleeve  4210 , positioned around the intermediate firing shaft portion  4120  of the firing member assembly  4110  wherein the lock sleeve  4210  can be rotated between an engaged position in which the lock sleeve  4210  couples the proximal articulation driver  3310  to the firing member assembly  4110  and a disengaged position in which the proximal articulation driver  3310  is not operably coupled to the firing member assembly  4110 . As was discussed above, the intermediate firing shaft portion  4120  of the firing member assembly  4110  is formed with a drive notch  4126 . The lock sleeve  4210  comprises a cylindrical, or an at least substantially cylindrical, body that includes a longitudinal aperture  4212  that is configured to receive the intermediate firing shaft portion  4120  therethrough. The lock sleeve  4210  can comprise diametrically-opposed, inwardly-facing lock protrusions  4214 ,  4216  that, when the lock sleeve  4210  is in one position, are engagingly received within corresponding portions of the drive notch  4126  in the intermediate firing shaft portion  4120  and, when in another position, are not received within the drive notch  4126  to thereby permit relative axial motion between the lock sleeve  4210  and the intermediate firing shaft  4120  as was discussed in further detail above. The lock sleeve  4210  further includes a lock member  4218  that is sized to be movably received within a notch  3319  in a proximal end of the proximal articulation driver  3310 . When the lock sleeve  4210  is in its engaged position, the lock protrusions  4214 ,  4216  are positioned within the drive notch  4126  in the intermediate firing shaft portion  4120  such that a distal pushing force and/or a proximal pulling force can be transmitted from the firing member assembly  4110  to the lock sleeve  4210 . Such axial pushing or pulling motion is then transmitted from the lock sleeve  4210  to the proximal articulation driver  3310  to thereby articulate the surgical end effector  3500 . 
     As was discussed above, in the illustrated example, relative movement of the lock sleeve  4210  between its engaged and disengaged positions may be controlled by the shifter assembly  4200  that interfaces with the proximal closure tube  3910  of the proximal closure assembly  3900 . The shifter assembly  4200  further includes a shifter key  4240  that is configured to be slidably received within a key groove (similar to the key groove  2217  illustrated in  FIG.  8   ) formed in the outer perimeter of the lock sleeve  4210 . Such arrangement enables the shifter key  4240  to move axially with respect to the lock sleeve  4210 . Operation of the shifter assembly  4200  may be identical to the operation of the shifter assembly  2200  which was described in further detail above and which will not be repeated again for brevity. Further details, alternative arrangements and drive configurations that may be employed are disclosed in other arrangements that may be employed are disclosed in U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950, U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541, and U.S. patent application Ser. No. 15/019,196, now U.S. Pat. No. 10,413,291, the as well as other disclosures that have been incorporated herein. 
     The interchangeable tool assembly  3000  can comprise a slip ring assembly  3230  which can be configured to conduct electrical power to and/or from the surgical end effector  3500  and/or communicate signals to and/or from the surgical end effector  3500 , back to a microprocessor  560  in the handle assembly  500  or robotic system controller, for example as was discussed above. Further details concerning the slip ring assembly  3230  and associated connectors may be found in U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541, and U.S. patent application Ser. No. 15/019,196 now U.S. Pat. No. 10,413,291, which have each been herein incorporated by reference in their respective entirety as well as in U.S. patent application Ser. No. 13/800,067, entitled STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, now U.S. Patent Application Publication No. 2014/0263552, which is hereby incorporated by reference herein in its entirety. 
     The illustrated interchangeable surgical tool assembly  3000  also employs a latch system  3220  for removably coupling the interchangeable surgical tool assembly  3000  to the handle frame  506  of the handle assembly  500 , for example. The latch system  3220  may be identical to the latch system  1220  described in detail above. The knife bar  4130  may comprise a laminated beam structure that includes at least two beam layers. Such beam layers may comprise, for example, stainless steel bands that are interconnected by, for example, welding or pinning together at their proximal ends and/or at other locations along their length. In alternative embodiments, the distal ends of the bands are not connected together to allow the laminates or bands to splay relative to each other when the end effector is articulated. Such arrangement permits the knife bar  4130  to be sufficiently flexible to accommodate articulation of the end effector. Various laminated knife bar arrangements are disclosed in U.S. patent application Ser. No. 15/019,245, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, which is hereby incorporated by reference in its entirety. As can also be seen in  FIG.  18   , a firing shaft support assembly  4300  is employed to provide lateral support to the knife bar  4130  as it flexes to accommodate articulation of the surgical end effector  3500 . Further details concerning the operation of the firing shaft support assembly  4300  and alternative knife bar support arrangements may be found in U.S. patent application Ser. No. 15/019,245, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, and U.S. patent application Ser. No. 15/019,220, entitled SURGICAL INSTRUMENT WITH ARTICULATING AND AXIALLY TRANSLATABLE END EFFECTOR, now U.S. Pat. No. 10,245,029, which are each hereby incorporated by reference herein in their respective entireties. 
     As can also be seen in  FIG.  18   , a firing member or knife member  4140  is attached to the distal end of the knife bar  4130 . The firing member  4140  is configured to operably interface with a sled assembly  4150  that is operably supported within the body  3702  of the surgical staple/fastener cartridge  3700 . The sled assembly  4150  is slidably displaceable within the surgical staple/fastener cartridge body  3702  from a proximal starting position adjacent the proximal end  3704  of the cartridge body  3702  to an ending position adjacent a distal end  3706  of the cartridge body  3702 . The cartridge body  3702  operably supports therein a plurality of staple drivers (not shown) that are aligned in rows on each side of a centrally disposed slot  3708 . The centrally disposed slot  3708  enables the firing member  4140  to pass therethrough and cut the tissue that is clamped between the anvil  3810  and the staple cartridge  3700 . The drivers are associated with corresponding staple pockets  3712  that open through the deck surface  3710  of the cartridge body  3702 . Each of the staple drivers supports one or more surgical staple/fastener or fastener (not shown) thereon. The sled assembly  4150  includes a plurality of sloped or wedge-shaped cams  4152  wherein each cam  4152  corresponds to a particular line of fasteners or drivers located on a side of the slot  3708 . 
     In one exemplary form, the firing member  4140  comprises a body portion  4142  that supports a knife or tissue cutting portion  4144 . See  FIG.  49   . The body portion  4142  protrudes through an elongate slot  3604  in the elongate channel  3602  and terminates in a foot member  4146  that extends laterally on each side of the body portion  4142 . As the firing member  4140  is driven distally through the surgical staple/fastener cartridge  3700 , the foot member  4146  rides within a passage  3622  in the elongate channel  3602  that is located under the surgical staple/fastener cartridge  3700 . The tissue cutting portion  4144  is disposed between a distally protruding top nose portion  4143 . As can be further seen in  FIG.  18   , the firing member  4140  may further include two laterally extending top tabs, pins or anvil engagement features  4147 . As the firing member  4140  is driven distally, a top portion of the body portion  4142  extends through a centrally disposed anvil slot  3814  and the anvil engagement features  4147  ride on corresponding ledges  3816  formed on each side of the anvil slot  3814 . Further details concerning the firing member  4140 , sled assembly  4150  and their various alternatives as well as examples of their operation will be discussed in further detail below and may also be found in U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950. The interchangeable surgical tool assembly  3000  may be to the handle assembly  500  in the manner as described above with respect to the interchangeable surgical tool assembly  1000 . 
     Returning again to  FIG.  1   , as was discussed above, the surgical system  10  illustrated in that Figure includes four interchangeable surgical tool assemblies  1000 ,  3000 ,  5000  and  7000  that may each be effectively employed with the same handle assembly  500  to perform different surgical procedures. Turning now to  FIGS.  19 - 21   , the interchangeable surgical tool assembly  5000  includes a surgical end effector  5500  that comprises a first jaw  5600  and a second jaw  5800 . In one arrangement, the first jaw comprises an elongate channel  5602  that is configured to operably support a surgical staple/fastener cartridge  5700  therein. The second jaw  5800  comprises an anvil  5810  that is movably supported relative to the elongate channel  5602 . The interchangeable surgical tool assembly  5000  includes an articulation system  5300  that comprises an articulation joint  5302  and an articulation lock  5400  which can be configured to releasably hold the surgical end effector  5500  in a desired articulated position relative to a shaft axis SA 3 . Details regarding the construction and operation of the articulation lock  5400  as well as alternative lock configurations and operational details may be found in U.S. patent application Ser. No. 15/385,894, entitled SHAFT ASSEMBLY COMPRISING A LOCK OUT, now U.S. Pat. No. 10,492,785, the entire disclosure of which is hereby incorporated by reference herein. Alternative articulation lock arrangements may also be found in U.S. patent application Ser. No. 13/803,086, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. Patent Application Publication No. 2014/0263541 and U.S. patent application Ser. No. 15/019,196, filed Feb. 9, 2016, entitled SURGICAL INSTRUMENT ARTICULATION MECHANISM WITH SLOTTED SECONDARY CONSTRAINT, now U.S. Pat. No. 10,413,291, the entire disclosures of each such reference being hereby incorporated by reference herein. 
     As can be seen in  FIG.  20   , the interchangeable surgical tool assembly  5000  includes a tool frame assembly  5200  that comprises a tool chassis  5210  that operably supports a nozzle assembly  5240  thereon. In one form, the nozzle assembly  5240  is comprised of nozzle portions  5242 ,  5244  as well as an actuator wheel portion  5246  that is configured to be coupled to the assembled nozzle portions  5242 ,  5244  by snaps, lugs, screws etc. The interchangeable surgical tool assembly  5000  includes a proximal closure assembly  5900  which is operably coupled to a distal closure assembly  6000  that is utilized to close and/or open the anvil  5810  of the surgical end effector  5500  as will be discussed in further detail below. In addition, the interchangeable surgical tool assembly  5000  includes a spine assembly  5250  that operably supports the proximal closure assembly  5900  and is coupled to the surgical end effector  5500 . In the illustrated arrangement, the spine assembly  5250  includes a distal end portion  5280  that has an opening  5281  therein for ease of assembly. A spine cap  5283  may be attached thereto to cover the opening  5281  after the various components have been assembled therein. In assembled form, a proximal end portion  5253  of the spine assembly  5250  is rotatably supported in the tool chassis  5210 . In one arrangement, for example, the proximal end of the proximal end portion  5253  of the spine assembly  5250  is attached to a spine bearing (not shown) that is configured to be supported within the tool chassis  5210 . Such arrangement facilitates rotatable attachment of the spine assembly  5250  to the tool chassis  5210  such that the spine assembly  5250  may be selectively rotated about the shaft axis SA 3  relative to the tool chassis  5210 . In particular, in one arrangement, for example, the proximal end portion  5253  of the spine assembly  5250  includes two diametrically opposed lug seats  5254  (only one can be seen in  FIG.  20   ) that are each configured to receive a corresponding nozzle lug (not shown) that extend inwardly from each of the nozzle portions  5242 ,  5244 . Such arrangement facilitates rotation of the spine assembly  5250  about the shaft axis SA 3  by rotating the actuator wheel portion  5246  of the nozzle assembly  5240 . 
     Referring now to  FIG.  21   , the distal end portion  5280  of the spine assembly  5250  is attached to a distal frame segment  5286  that operably supports the articulation lock  5400  therein. The spine assembly  5250  is configured to, one, slidably support a firing member assembly  6110  therein and, two, slidably support a proximal closure tube  5910  which extends around the spine assembly  5250 . The spine assembly  5250  can also be configured to slidably support a first articulation driver  5310  and a second articulation driver  5320 . As can be seen in  FIG.  21   , the distal frame segment  5286  is pivotally coupled to a proximal end  5610  of the elongate channel  5602 . In one arrangement, for example, the distal end of the distal frame segment  5286  has a pivot pin  5288  formed thereon. The pivot pin  5288  is adapted to be pivotally received within a pivot hole  5611  formed in the proximal end portion  5610  of the elongate channel  5602 . The pivot pin  5288  defines an articulation axis AA 3  that is transverse to the shaft axis SA 3 . See  FIG.  21   . Such arrangement facilitates pivotal travel (i.e., articulation) of the surgical end effector  5500  about the articulation axis AA 3  relative to the spine assembly  5250 . The distal frame segment  5286  is further configured to support the articulation lock  5400  therein. 
     In the illustrated arrangement, a distal end  5314  of the first articulation driver  5310  is formed with a loop  5316  that is adapted to receive a first articulation pin  5618  therein that is formed on the proximal end portion  5610  of the elongate channel  5602 . Similarly, a distal end  5324  of the second articulation driver  5320  has a loop  5326  that is adapted to receive a second articulation pin  5619  therein that is formed on the proximal end portion  5610  of the elongate channel  5602 . In one arrangement, for example, the first articulation driver  5310  further comprises a proximal rack of teeth  5315  that is in meshing engagement with an idler gear  5330  rotatably supported in the spine assembly  5250 . Similarly the second articulation driver  5320  further comprises a proximal rack of teeth  5325  that is in meshing engagement with the idler gear  5330 . Thus, in such arrangement, movement of the first articulation driver  5310  in the distal direction DD will result in movement of the second articulation driver  5320  in the proximal direction PD. Movement of the first articulation driver  5310  in the proximal direction PD will result in the movement of the second articulation driver  5320  in the distal direction DD. Thus, such movement of the first and second articulation drivers  5310 ,  5320  will provide simultaneously pushing and pulling motions to the surgical end effector  5500  to articulate the surgical end effector about the articulation axis AA 3 . 
     The anvil  5810  in the illustrated example includes an anvil body  5812  that terminates in anvil mounting portion  5820 . The anvil mounting portion  5820  is movably supported on the elongate channel  5602  for selective pivotal and vertical travel relative thereto. In the illustrated arrangement, an anvil trunnion  5822  extends laterally out of each lateral side of the anvil mounting portion  5820  to be received in a corresponding “open-ended” vertical cradle  5613  formed in upstanding walls  5612  of the proximal end portion  5610  of the elongate channel  5602 . Movement of the anvil  5810  relative to the elongate channel  5602  is effectuated by axial movement of the proximal closure assembly  5900  and the distal closure assembly  6000 . In the illustrated arrangement, the proximal closure assembly  5900  comprises the proximal closure tube  5910  that has a proximal end  5912  and a distal end  5914 . The proximal end  5912  is rotatably supported in a closure shuttle  5940  that is slidably supported within the tool chassis  5210  such that it may be axially moved relative thereto. In one form, the closure shuttle  5940  includes a pair of proximally-protruding hooks  5942  that are configured for attachment to the transverse attachment pin  516  that is attached to the closure linkage assembly  514  of the handle assembly  500 . The proximal end  5912  of the proximal closure tube  5910  is coupled to the closure shuttle  5940  for relative rotation thereto. For example, a U-shaped connector  5944  is inserted into an annular slot  5916  in the proximal end  5912  and is retained within vertical slots  5946  in the closure shuttle  5940 . Such arrangement serves to attach the proximal closure assembly  5900  to the closure shuttle  5940  for axial travel therewith while enabling the proximal closure tube  5910  to rotate relative to the closure shuttle  5940  about the shaft axis SA 3 . As was discussed above in connection with the interchangeable surgical tool assembly  1000 , a closure spring (not shown) may extend over the proximal end  5912  of the proximal closure tube  5910  to bias the closure shuttle  5940  in the proximal direction PD which can serve to pivot the closure trigger  512  on the handle assembly  500  ( FIG.  2   ) into the unactuated position when the interchangeable surgical tool assembly  5000  is operably coupled to the handle assembly  500  in the above described manner. 
     As can be seen in  FIG.  21   , the distal end  5914  of the proximal closure tube  5910  is attached to the distal closure assembly  6000 . The distal end  5914  includes upper and lower tangs  5917 ,  7918  that are configured to be movably coupled to an end effector closure sleeve or distal closure tube segment  6030 . The distal closure tube segment  6030  includes an upper tang  6032  and a lower tang  6034  that protrude proximally from a proximal end thereof. An upper double pivot link  6060  pivotally couples the upper tangs  5917  and  6032  and a lower double pivot link  6064  pivotally couples the lower tangs  5918  and  6034  together in the above-described manner. The distal closure tube segment  6030  includes an internal cam surface  6036  that is configured to cammingly engage an anvil cam surface  5821  on the anvil mounting portion  5820 . The distal advancement of the distal closure tube segment  6030  on the anvil mounting portion  5820  will result in closure or pivotal travel of the anvil  5810  towards the elongate channel  5602 . In the illustrated arrangement, upstanding anvil tabs  5827  are formed on the anvil mounting portion  5820  and are configured to be contacted by two positive jaw opening tabs  6038  that extend inwardly within the distal closure tube segment  6030 . Each positive jaw opening tab  6038  is configured to engage a corresponding one of the anvil tabs  5827  to pivot the anvil  5810  to an open position when the distal closure tube segment  6030  is axially moved in the proximal direction PD. 
     In the illustrated arrangement, the interchangeable surgical tool assembly  5000  further includes a firing system generally designated as  6100 . In various instances, the firing system  6100  includes the firing member assembly  6110  that is supported for axial travel within the spine assembly  5250 . In the illustrated embodiment, the firing member assembly  6110  includes an intermediate firing shaft portion  6120  that is configured for attachment to a distal cutting portion or knife bar  6130 . The firing member assembly  6110  may also be referred to herein as a “second shaft” and/or a “second shaft assembly”. As can be seen in  FIG.  21   , the intermediate firing shaft portion  6120  may include a longitudinal slot  6124  in a distal end  6122  thereof which can be configured to receive a proximal end  6132  of the knife bar  6130 . The longitudinal slot  6124  and the proximal end  6132  of the knife bar  6130  can be sized and configured to permit relative movement therebetween and can comprise a slip joint  6134 . The slip joint  6134  can permit the intermediate firing shaft portion  6120  of the firing member assembly  6110  to be moved to articulate the end effector  5500  without moving, or at least substantially moving, the knife bar  6130  as was discussed above. In the illustrated arrangement, a proximal end  6127  of the intermediate firing shaft portion  6120  has a firing shaft attachment lug  6128  formed thereon that is configured to be seated into an attachment cradle (not shown) that is on the distal end of the longitudinally movable drive member (not shown) of the firing drive system  530  within the handle assembly  500  as was discussed above. Such arrangement facilitates the axial movement of the intermediate firing shaft portion  6120  upon actuation of the firing drive system  530 . Other attachment configurations may also be employed to couple the intermediate firing shaft portion to other firing drive arrangements (e.g., manually actuated, robotic, etc.). 
     Further to the above, the interchangeable tool assembly  5000  can include a shifter assembly  6200  which can be configured to selectively and releasably couple the first articulation driver  5310  to the firing member assembly  6110  in the manner described above. In one form, the shifter assembly  6200  includes a lock collar, or lock sleeve  6210 , positioned around the intermediate firing shaft portion  6120  of the firing member assembly  6110  wherein the lock sleeve  6210  can be rotated between an engaged position in which the lock sleeve  6210  couples the first articulation driver  5310  to the firing member assembly  6110  and a disengaged position in which the first articulation driver  5310  is not operably coupled to the firing member assembly  6110 . As was discussed above, the intermediate firing shaft portion  6120  of the firing member assembly  6110  is formed with a drive notch  6126 . The lock sleeve  6210  comprises a cylindrical, or an at least substantially cylindrical, body that includes a longitudinal aperture that is configured to receive the intermediate firing shaft portion  6120  therethrough. The lock sleeve  6210  can comprise diametrically-opposed, inwardly-facing lock protrusions  6214 ,  6216  that, when the lock sleeve  6210  is in one position, are engagingly received within corresponding portions of the drive notch  6126  in the intermediate firing shaft portion  6120  and, when in another position, are not received within the drive notch  6126  to thereby permit relative axial motion between the lock sleeve  6210  and the intermediate firing shaft  6120  as was discussed in further detail above. The lock sleeve  6210  further includes a lock member  6218  that is sized to be movably received within a notch  5319  in a proximal end of the first articulation driver  5310 . When the lock sleeve  6210  is in its engaged position, the lock protrusions  6214 ,  6216  are positioned within the drive notch  6126  in the intermediate firing shaft portion  6120  such that a distal pushing force and/or a proximal pulling force can be transmitted from the firing member assembly  6110  to the lock sleeve  6210 . Such axial pushing or pulling motion is then transmitted from the lock sleeve  6210  to the first articulation driver  5310 . Axial movement of the first articulation driver  5310  results in the axial movement of the second articulation driver  5320  in an opposite direction to thereby articulate the surgical end effector  5500 . 
     As was discussed above, in the illustrated example, relative movement of the lock sleeve  6210  between its engaged and disengaged positions may be controlled by the shifter assembly  6200  that interfaces with the proximal closure tube  5910  of the proximal closure assembly  5900 . The shifter assembly  6200  further includes a shifter key  6240  that is configured to be slidably received within a key groove (similar to the key groove  2217  illustrated in  FIG.  8   ) formed in the outer perimeter of the lock sleeve  6210 . Such arrangement enables the shifter key  6240  to move axially with respect to the lock sleeve  6210 . Operation of the shifter assembly  6200  may be identical to the operation of the shifter assembly  2200  which was described in further detail above and which will not be repeated again for brevity. Further details, alternative arrangements and drive configurations that may be employed are disclosed in Other arrangements that may be employed are disclosed in U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950, U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541, and U.S. patent application Ser. No. 15/019,196, now U.S. Pat. No. 10,413,291, the as well as other disclosures that have been incorporated herein. 
     The interchangeable tool assembly  5000  can comprise a slip ring assembly  5230  which can be configured to conduct electrical power to and/or from the surgical end effector  5500  and/or communicate signals to and/or from the surgical end effector  5500 , back to a microprocessor  560  in the handle assembly  500  or robotic system controller, for example as was discussed above. Further details concerning the slip ring assembly  5230  and associated connectors may be found in U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541, and U.S. patent application Ser. No. 15/019,196, now U.S. Pat. No. 10,413,291, which have each been herein incorporated by reference in their respective entirety as well as in U.S. patent application Ser. No. 13/800,067, entitled STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, now U.S. Patent Application Publication No. 2014/0263552, which is hereby incorporated by reference herein in its entirety. 
     The illustrated interchangeable surgical tool assembly  5000  also employs a latch system  5220  for removably coupling the interchangeable surgical tool assembly  5000  to the handle frame  506  of the handle assembly  500 , for example. The latch system  5220  may be identical to the latch system  1220  described in detail above. The knife bar  6130  may comprise a laminated beam structure that includes at least two beam layers. Such beam layers may comprise, for example, stainless steel bands that are interconnected by, for example, welding or pinning together at their proximal ends and/or at other locations along their length. In alternative embodiments, the distal ends of the bands are not connected together to allow the laminates or bands to splay relative to each other when the end effector is articulated. Such arrangement permits the knife bar  6130  to be sufficiently flexible to accommodate articulation of the end effector. Various laminated knife bar arrangements are disclosed in U.S. patent application Ser. No. 15/019,245, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, which is hereby incorporated by reference in its entirety. As can also be seen in  FIG.  21   , a firing shaft support assembly  6300  is employed to provide lateral support to the knife bar  6130  as it flexes to accommodate articulation of the surgical end effector  5500 . Further details concerning the operation of the firing shaft support assembly  6300  and alternative knife bar support arrangements may be found in U.S. patent application Ser. No. 15/019,245, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, and U.S. patent application Ser. No. 15/019,220, entitled SURGICAL INSTRUMENT WITH ARTICULATING AND AXIALLY TRANSLATABLE END EFFECTOR, now U.S. Pat. No. 10,245,029, which are each hereby incorporated by reference herein in their respective entireties. 
     As can also be seen in  FIGS.  21  and  50   , a firing member or knife member  6140  is attached to the distal end of the knife bar  6130 . The firing member  6140  is configured to operably interface with a sled assembly  6150  that is operably supported within the body  5702  of the surgical staple/fastener cartridge  5700 . The sled assembly  6150  is slidably displaceable within the surgical staple/fastener cartridge body  5702  from a proximal starting position adjacent a proximal end  5704  of the cartridge body  5702  to an ending position adjacent a distal end  5706  of the cartridge body  5702 . The cartridge body  5702  operably supports therein a plurality of staple drivers (not shown) that are aligned in rows on each side of a centrally disposed slot  5708 . The centrally disposed slot  5708  enables the firing member  6140  to pass therethrough and cut the tissue that is clamped between the anvil  5810  and the staple cartridge  5700 . The drivers are associated with corresponding staple pockets that open through the upper deck surface of the cartridge body  5702 . Each of the staple drivers supports one or more surgical staple/fastener or fastener (not shown) thereon. The sled assembly includes a plurality of sloped or wedge-shaped cams  6152  wherein each cam corresponds to a particular line of fasteners or drivers located on a side of the slot  5708 . 
     In one exemplary form, the firing member  6140  comprises a body portion  6142  that supports a knife or tissue cutting portion  6144 . See  FIG.  50   . The body portion  6142  protrudes through an elongate slot  5604  in the elongate channel  5602  and terminates in a foot member  6146  that extends laterally on each side of the body portion  6142 . As the firing member  6140  is driven distally through the surgical staple/fastener cartridge  5700 , the foot member  6146  rides within a passage  5622  in the elongate channel  5602  that is located under the surgical staple/fastener cartridge  5700 . The tissue cutting portion  6144  is disposed between a distally protruding top nose portion  6143 . As can be further seen in  FIGS.  21  and  50   , the firing member  6140  may further include two laterally extending top tabs, pins or anvil engagement features  6147 . As the firing member  6140  is driven distally, a top portion of the body portion  6142  extends through a centrally disposed anvil slot  5814  and the anvil engagement features  6147  ride on corresponding ledges  5816  formed on each side of the anvil slot  5814 . Further details concerning the firing member  6140 , sled assembly  6150 , and their various alternatives as well as examples of their operation will be discussed in further detail below and may also be found in U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950. The interchangeable surgical tool assembly  5000  may be operably coupled to the handle assembly  500  in the manner as described above with respect to the interchangeable surgical tool assembly  1000 . 
     Returning again to  FIG.  1   , as was discussed above, the surgical system  10  illustrated in that Figure includes four interchangeable surgical tool assemblies  1000 ,  3000 ,  5000  and  7000  that may each be effectively employed with the same handle assembly  500  to perform different surgical procedures. Turning now to  FIGS.  22 - 24   , the interchangeable surgical tool assembly  7000  includes a surgical end effector  7500  that comprises a first jaw  7600  and a second jaw  7800 . In one arrangement, the first jaw comprises an elongate channel  7602  that is configured to operably support a surgical staple/fastener cartridge  7700  therein. The second jaw  7800  comprises an anvil  7810  that is movably supported relative to the elongate channel  7602 . The interchangeable surgical tool assembly  7000  includes an articulation system  7300  that comprises an articulation joint  7302  and an articulation lock  7400  which can be configured to releasably hold the surgical end effector  7500  in a desired articulated position relative to a shaft axis SA 4 . Details regarding the construction and operation of the articulation lock  7400  as well as alternative lock configurations and operational details may be found in U.S. patent application Ser. No. 13/803,086, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. Patent Application Publication No. 2014/0263541, the entire disclosure of which is hereby incorporated by reference herein. Additional details concerning the articulation lock  7400  and/or alternative articulation lock arrangements may also be found in U.S. patent application Ser. No. 15/019,196, filed Feb. 9, 2016, entitled SURGICAL INSTRUMENT ARTICULATION MECHANISM WITH SLOTTED SECONDARY CONSTRAINT, now U.S. Pat. No. 10,413,291, the entire disclosure of which is hereby incorporated by reference herein. 
     As can be seen in  FIG.  24   , the interchangeable surgical tool assembly  7000  includes a tool frame assembly  7200  that comprises a tool chassis  7210  that operably supports a nozzle assembly  7240  thereon. In one form, the nozzle assembly  7240  is comprised of nozzle portions  7242 ,  7244  as well as an actuator wheel portion  7246  that is configured to be coupled to the assembled nozzle portions  7242 ,  7244  by snaps, lugs, screws etc. The interchangeable surgical tool assembly  7000  includes a proximal closure assembly  7900  which is operably coupled to a distal closure assembly  8000  that is utilized to close and/or open the anvil  7810  of the surgical end effector  7500  as will be discussed in further detail below. In addition, the interchangeable surgical tool assembly  7000  includes a spine assembly  7250  that operably supports the proximal closure assembly  7900  and is coupled to the surgical end effector  3500 . In the illustrated arrangement, the spine assembly  7250  includes a distal end portion  7280  that has an opening  7281  therein for ease of assembly. A spine cap  7283  may be attached thereto to cover the opening  7281  after the various components have been assembled therein. In assembled form, a proximal end portion  7253  of the spine assembly  7250  is rotatably supported in the tool chassis  7210 . In one arrangement, for example, the proximal end of the proximal end portion  7253  of the spine assembly  7250  is attached to a spine bearing (not shown) that is configured to be supported within the tool chassis  7210 . Such arrangement facilitates rotatable attachment of the spine assembly  7250  to the tool chassis  7210  such that the spine assembly  7250  may be selectively rotated about the shaft axis SA 4  relative to the tool chassis  7210 . In particular, in one arrangement, for example, the proximal end portion  7253  of the spine assembly  7250  includes two diametrically opposed lug seats  7254  (only one can be seen in  FIG.  23   ) that are each configured to receive a corresponding nozzle lug (not shown) that extend inwardly from each of the nozzle portions  7242 ,  7244 . Such arrangement facilitates rotation of the spine assembly  7250  about the shaft axis SA 4  by rotating the actuator wheel portion  7246  of the nozzle assembly  7240 . 
     Referring now to  FIG.  24   , the distal end portion  7280  of the spine assembly  7250  is attached to a distal frame segment  7286  that operably supports the articulation lock  7400  therein. The spine assembly  7250  is configured to, one, slidably support a firing member assembly  8110  therein and, two, slidably support a proximal closure tube  7910  which extends around the spine assembly  7250 . The spine assembly  7250  can also be configured to slidably support a proximal articulation driver  7310 . As can be seen in  FIG.  24   , the distal frame segment  7286  is pivotally coupled to the elongate channel  7602  by an end effector mounting assembly  7290 . In one arrangement, for example, the distal end of the distal frame segment  7286  has a pivot pin  7288  formed thereon. The pivot pin  7288  is adapted to be pivotally received within a pivot hole  7292  formed in pivot base portion  7291  of the end effector mounting assembly  7290 . The end effector mounting assembly  7290  is attached to a proximal end portion  7610  of the elongate channel  7602  by a spring pin  7620  or other suitable member that is received within mounting holes  7611  in the proximal end portion  7610 . The pivot pin  7288  defines an articulation axis AA 4  that is transverse to the shaft axis SA 4 . See  FIG.  24   . Such arrangement facilitates pivotal travel (i.e., articulation) of the surgical end effector  7500  about the articulation axis AA 4  relative to the spine assembly  7250 . The distal frame segment  7286  is further configured to support the articulation lock  7400  therein. Various articulation lock arrangements may be employed. At least one form of articulation lock  7400  is described in further detail in U.S. patent application Ser. No. 13/803,086, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING AN ARTICULATION LOCK, now U.S. Patent Application Publication No. 2014/0263541, the entire disclosure of which is hereby incorporated by reference herein. Additional details concerning the articulation lock may also be found in U.S. patent application Ser. No. 15/019,196, filed Feb. 9, 2016, entitled SURGICAL INSTRUMENT ARTICULATION MECHANISM WITH SLOTTED SECONDARY CONSTRAINT, now U.S. Pat. No. 10,413,291. 
     In the illustrated example, the surgical end effector  7500  is electively articulatable about the articulation axis AA 4  by the articulation system  7300 . In one form, the articulation system  7300  includes the proximal articulation driver  7310  that operably interfaces with the articulation lock  7400 . The articulation lock  7400  includes an articulation frame  7402  that is adapted to operably engage a drive pin  7293  on the pivot base portion  7291  of the end effector mounting assembly  7290 . In addition, a cross link  7294  may be linked to the drive pin  7293  and articulation frame  7402  to assist articulation of the surgical end effector  7500 . As indicated above, further details regarding the operation of the articulation lock  7400  and the articulation frame  7402  may be found in U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541. Further details regarding the end effector mounting assembly and cross link  7294  may be found in U.S. patent application Ser. No. 15/019,245, filed Feb. 9, 2016, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, the entire disclosure of which is hereby incorporated by reference herein. As further described therein, as well as in other disclosures incorporated by reference herein, axial movement of proximal articulation driver  7310  will result in the engagement/disengagement of the articulation lock  7400  to thereby apply articulation motions to the elongate channel  7602  and thereby cause the surgical end effector  7500  to articulate about the articulation axis AA 4  relative to the spine assembly  7250 . 
     The anvil  7810  in the illustrated example includes an anvil body  7812  that terminates in anvil mounting portion  7820 . The anvil mounting portion  7820  is movably supported on the elongate channel  7602  for selective pivotal and axial travel relative thereto. In the illustrated arrangement, an anvil trunnion  7822  extends laterally out of each lateral side of the anvil mounting portion  7820  to be received in a corresponding “kidney-shaped” opening  7613  formed in upstanding walls  7612  of the proximal end portion  7610  of the elongate channel  7602 . Movement of the anvil  7810  relative to the elongate channel  7602  is effectuated by axial movement of the proximal closure assembly  7900  and the distal closure assembly  8000 . In the illustrated arrangement, the proximal closure assembly  7900  comprises the proximal closure tube  7910  that has a proximal end  7912  and a distal end  7914 . The proximal end  7912  is rotatably supported in a closure shuttle  7940  that is slidably supported within the tool chassis  7210  such that it may be axially moved relative thereto. In one form, the closure shuttle  7940  includes a pair of proximally-protruding hooks  7942  that are configured for attachment to the transverse attachment pin  516  that is attached to the closure linkage assembly  514  of the handle assembly  500 . The proximal end  7912  of the proximal closure tube  7910  is coupled to the closure shuttle  7940  for relative rotation thereto. For example, a U-shaped connector  7944  is inserted into an annular slot  7916  in the proximal end  7912  of the proximal closure tube  7910  and is retained within vertical slots  7946  in the closure shuttle  7940 . Such arrangement serves to attach the proximal closure assembly  7900  to the closure shuttle  7940  for axial travel therewith while enabling the proximal closure tube  7910  to rotate relative to the closure shuttle  7940  about the shaft axis SA 4 . As was discussed above in connection with the interchangeable surgical tool assembly  1000 , a closure spring (not shown) may extend over the proximal end  7912  of the proximal closure tube  7910  to bias the closure shuttle  7940  in the proximal direction PD which can serve to pivot the closure trigger  512  on the handle assembly  500  ( FIG.  2   ) into the unactuated position when the interchangeable surgical tool assembly  7000  is operably coupled to the handle assembly  500  in the above described manner. 
     As can be seen in  FIG.  24   , the distal end  7914  of the proximal closure tube  3910  is attached to the distal closure assembly  8000 . The distal end  7914  includes upper and lower tangs  7917 ,  7918  that are configured to be movably coupled to an end effector closure sleeve or distal closure tube segment  8030 . The distal closure tube segment  8030  includes an upper tang  8032  and a lower tang  8034  that protrude proximally from a proximal end thereof. An upper double pivot link  8060  pivotally couples the upper tangs  7917  and  8032  and a lower double pivot link  8064  pivotally couples the lower tangs  7918  and  8034  together in the above-described manner. The distal advancement of the distal closure tube segment  8030  on the anvil mounting portion  7820  will result in closure or pivotal travel of the anvil  7810  towards the elongate channel  7602 . In the illustrated arrangement, an upstanding anvil tab  7824  is formed on the anvil mounting portion  7820  and extends into a horseshoe-shaped opening  8038 . Opening  8038  defines an opening tab  8039  configured to operably interface with the anvil tab  7824  as the distal closure tube is retracted in the distal direction. Such interaction between the opening tab  8039  and the anvil tab  7824  applies an opening motion to the anvil  7810  to thereby cause the anvil  7810  to move to an open position. 
     In the illustrated arrangement, the interchangeable surgical tool assembly  7000  further includes a firing system generally designated as  8100 . In various instances, the firing system  8100  includes the firing member assembly  8110  that is supported for axial travel within the spine assembly  7250 . In the illustrated embodiment, the firing member assembly  8110  includes an intermediate firing shaft portion  8120  that is configured for attachment to a distal cutting portion or knife bar  8130 . The firing member assembly  8110  may also be referred to herein as a “second shaft” and/or a “second shaft assembly”. As can be seen in  FIG.  24   , the intermediate firing shaft portion  8120  may include a longitudinal slot  8124  in a distal end  8122  thereof which can be configured to receive a proximal end  8132  of the knife bar  8130 . The longitudinal slot  8124  and the proximal end  8132  of the knife bar  8130  can be sized and configured to permit relative movement therebetween and can comprise a slip joint  8134 . The slip joint  8134  can permit the intermediate firing shaft portion  8120  of the firing member assembly  8110  to be moved to articulate the end effector  7500  without moving, or at least substantially moving, the knife bar  8130  as was discussed above. In the illustrated arrangement, a proximal end  8127  of the intermediate firing shaft portion  8120  has a firing shaft attachment lug  8128  formed thereon that is configured to be seated into an attachment cradle (not shown) that is on the distal end of the longitudinally movable drive member (not shown) of the firing drive system  530  within the handle assembly  500  as was discussed above. Such arrangement facilitates the axial movement of the intermediate firing shaft portion  8120  upon actuation of the firing drive system  530 . Other attachment configurations may also be employed to couple the intermediate firing shaft portion to other firing drive arrangements (e.g., manually actuated, robotic, etc.). 
     Further to the above, the interchangeable tool assembly  7000  can include a shifter assembly  8200  which can be configured to selectively and releasably couple the proximal articulation driver  7310  to the firing member assembly  8110  in the manner described above. In one form, the shifter assembly  8200  includes a lock collar, or lock sleeve  8210 , positioned around the intermediate firing shaft portion  8120  of the firing member assembly  8110  wherein the lock sleeve  8210  can be rotated between an engaged position in which the lock sleeve  8210  couples the proximal articulation driver  7310  to the firing member assembly  8110  and a disengaged position in which the proximal articulation driver  7310  is not operably coupled to the firing member assembly  8110 . As was discussed above, the intermediate firing shaft portion  8120  of the firing member assembly  8110  is formed with a drive notch  8126 . The lock sleeve  8210  comprises a cylindrical, or an at least substantially cylindrical, body that includes a longitudinal aperture that is configured to receive the intermediate firing shaft portion  8120  therethrough. The lock sleeve  8210  can comprise diametrically-opposed, inwardly-facing lock protrusions  8214 ,  8216  that, when the lock sleeve  8210  is in one position, are engagingly received within corresponding portions of the drive notch  8126  in the intermediate firing shaft portion  8120  and, when in another position, are not received within the drive notch  8126  to thereby permit relative axial motion between the lock sleeve  8210  and the intermediate firing shaft  8120  as was discussed in further detail above. The lock sleeve  8210  further includes a lock member  8218  that is sized to be movably received within a notch  7319  in a proximal end of the proximal articulation driver  7310 . When the lock sleeve  8210  is in its engaged position, the lock protrusions  8214 ,  8216  are positioned within the drive notch  7126  in the intermediate firing shaft portion  8120  such that a distal pushing force and/or a proximal pulling force can be transmitted from the firing member assembly  8110  to the lock sleeve  8210 . Such axial pushing or pulling motion is then transmitted from the lock sleeve  8210  to the proximal articulation driver  7310  to thereby articulate the surgical end effector  7500 . 
     As was discussed above, in the illustrated example, relative movement of the lock sleeve  8210  between its engaged and disengaged positions may be controlled by the shifter assembly  8200  that interfaces with the proximal closure tube  7910  of the proximal closure assembly  7900 . The shifter assembly  8200  further includes a shifter key  8240  that is configured to be slidably received within a key groove (similar to the key groove  2217  illustrated in  FIG.  8   ) formed in the outer perimeter of the lock sleeve  8210 . Such arrangement enables the shifter key  8240  to move axially with respect to the lock sleeve  8210 . Operation of the shifter assembly  8200  may be identical to the operation of the shifter assembly  2200  which was described in further detail above and which will not be repeated again for brevity. Further details, alternative arrangements and drive configurations that may be employed are disclosed in Other arrangements that may be employed are disclosed in U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950, U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541, and U.S. patent application Ser. No. 15/019,196, now U.S. Pat. No. 10,413,291, the as well as other disclosures that have bee incorporated herein. 
     The interchangeable tool assembly  7000  can comprise a slip ring assembly  7230  which can be configured to conduct electrical power to and/or from the surgical end effector  7500  and/or communicate signals to and/or from the surgical end effector  7500 , back to a microprocessor  560  in the handle assembly  500  or robotic system controller, for example as was discussed above. Further details concerning the slip ring assembly  7230  and associated connectors may be found in U.S. patent application Ser. No. 13/803,086, now U.S. Patent Application Publication No. 2014/0263541, and U.S. patent application Ser. No. 15/019,196, now U.S. Pat. No. 10,413,291, which have each been herein incorporated by reference in their respective entirety as well as in U.S. patent application Ser. No. 13/800,067, entitled STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, now U.S. Patent Application Publication No. 2014/0263552, which is hereby incorporated by reference herein in its entirety. 
     The illustrated interchangeable surgical tool assembly  7000  also employs a latch system  7220  for removably coupling the interchangeable surgical tool assembly  7000  to the handle frame  506  of the handle assembly  500 , for example. The latch system  7220  may be identical to the latch system  1220  described in detail above. The knife bar  8130  may comprise a laminated beam structure that includes at least two beam layers. Such beam layers may comprise, for example, stainless steel bands that are interconnected by, for example, welding or pinning together at their proximal ends and/or at other locations along their length. In alternative embodiments, the distal ends of the bands are not connected together to allow the laminates or bands to splay relative to each other when the end effector is articulated. Such arrangement permits the knife bar  8130  to be sufficiently flexible to accommodate articulation of the end effector. Various laminated knife bar arrangements are disclosed in U.S. patent application Ser. No. 15/019,245, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, which is hereby incorporated by reference in its entirety. As can also be seen in  FIG.  24   , a firing shaft support assembly  8300  is employed to provide lateral support to the knife bar  8130  as it flexes to accommodate articulation of the surgical end effector  7500 . Further details concerning the operation of the firing shaft support assembly  8300  and alternative knife bar support arrangements may be found in U.S. patent application Ser. No. 15/019,245, entitled SURGICAL INSTRUMENTS WITH CLOSURE STROKE REDUCTION ARRANGEMENTS, now U.S. Pat. No. 10,470,764, and U.S. patent application Ser. No. 15/019,220, entitled SURGICAL INSTRUMENT WITH ARTICULATING AND AXIALLY TRANSLATABLE END EFFECTOR, now U.S. Pat. No. 10,245,029, which are each hereby incorporated by reference herein in their respective entireties. 
     As can also be seen in  FIG.  24   , a firing member or knife member  8140  is attached to the distal end of the knife bar  8130 . The firing member  8140  is configured to operably interface with a sled assembly  8150  that is operably supported within the body  7702  of the surgical staple/fastener cartridge  7700 . See  FIG.  51   . The sled assembly  8150  is slidably displaceable within the surgical staple/fastener cartridge body  7702  from a proximal starting position adjacent a proximal end  7704  of the cartridge body  7702  to an ending position adjacent a distal end  7706  of the cartridge body  7702 . The cartridge body  7702  operably supports therein a plurality of staple drivers (not shown) that are aligned in rows on each side of a centrally disposed slot  7708 . The centrally disposed slot  7708  enables the firing member  8140  to pass therethrough and cut the tissue that is clamped between the anvil  7810  and the staple cartridge  7700 . The drivers are associated with corresponding staple pockets that open through the upper deck surface of the cartridge body  7702 . Each of the staple drivers supports one or more surgical staple/fastener or fastener (not shown) thereon. The sled assembly includes a plurality of sloped or wedge-shaped cams wherein each cam corresponds to a particular line of fasteners or drivers located on a side of the slot  7708 . 
     In one exemplary form, the firing member  8140  comprises a body portion  8142  that supports a knife or tissue cutting portion  8144 . See  FIG.  51   . The body portion  8142  protrudes through an elongate slot  7604  in the elongate channel  7602  and terminates in a foot member  8146  that extends laterally on each side of the body portion  8142 . As the firing member  8140  is driven distally through the surgical staple/fastener cartridge  7700 , the foot member  8146  rides within a passage  7622  in the elongate channel  7602  that is below the staple cartridge  7700 . The tissue cutting portion  8144  is disposed between a distally protruding top nose portion  8143 . As can be further seen in  FIG.  24   , the firing member  8140  may further include two laterally extending top tabs, pins or anvil engagement features  8147 . As the firing member  8140  is driven distally, a top portion of the body portion  8142  extends through a centrally disposed anvil slot  7814  and the anvil engagement features  8147  ride on corresponding ledges  7816  formed on each side of the anvil slot  7814 . Further details concerning the firing member  8140 , sled assembly  8150 , and their various alternatives as well as examples of their operation will be discussed in further detail below and may also be found in U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950. The interchangeable surgical tool assembly  7000  may be operably coupled to the handle assembly  500  in the manner as described above with respect to the interchangeable surgical tool assembly  1000 . 
     As can be appreciated from the foregoing descriptions, the interchangeable surgical tool assemblies described herein may be actuated by the same handle assembly, robotic system or other automated actuation system. All of the above described interchangeable surgical tool assemblies comprise surgical cutting and fastening instruments that have somewhat similar closure and firing components. However, the closure and firing systems and components of each of these tool assemblies have differences that may seem somewhat subtle at first blush, but, as will be further discussed below, such differences can result in significant improvements in the material composition, design, construction, manufacture and use of such tools. As will become apparent as the present Detailed Description proceeds, the interchangeable surgical tool assembly  1000  contains subtle design differences when compared to the other interchangeable surgical tool assemblies  3000 ,  5000 ,  7000  described herein that can result in significant improvements in the overall functionality, reliability, and cost of the tool assembly. Moreover, we have discovered that, in some cases, a synergistic effect exists between certain component arrangements employed by the tool assembly  1000  which can further enhance the overall efficiency and functionality of the tool assembly  1000 . In order to better understand these differences and improvements, certain components and systems of each of the tool assemblies  1000 ,  3000 ,  5000 ,  7000  will now be further described and compared to each other below. 
     For example, each of the interchangeable surgical tool assemblies  1000 ,  3000 ,  5000 ,  7000  must be able to apply a sufficient amount of closure force to cause the jaws to sufficiently clamp the target tissue so as to permit the firing member to properly treat the clamped tissue upon actuation of the firing drive system. For example, in the illustrated assemblies, the respective closure system components must be able to clamp the anvil and surgical staple/fastener cartridge onto the target tissue to enable the firing member to properly sever the clamped tissue and eject lines of staples or fasteners on each side of the tissue cut line. Depending upon the thickness and composition of the target tissue, significant closure forces and firing forces are often required. Thus, the closure and firing drive systems in the handle assembly housing, robotic housing, etc. must be able to generate such forces of sufficient magnitude (through the use of a motor or manually generated motion, for example) to sufficiently close the jaws and fire the firing member through the clamped tissue. Such procedures further require that the components within the interchangeable shaft assemblies to be sufficiently robust to accommodate the magnitudes of the forces being transmitted therethrough. In the past, the magnitudes of such forces often dictated that the closure system components, as well as the firing system components, be fabricated from metal or other suitable materials with relatively large cross-sectional thicknesses and of substantial reinforced configurations. 
     The tissue loads encountered during the clamping process typically create a large “moment” about the anvil pivot axis PA. The closure system components must be designed to counteract such moment. In various circumstances, for example, a moment about the anvil pivot axis PA in the opposite direction is needed. To maximize the efficiency of the system (e.g., minimize the magnitude of the force applied), the largest practical moment arm is desired. However, as will be further discussed below, there are trade-offs with other design variables when seeking to establish a large counter moment. For example, there is a balance between the distance from the articulation joint to the first staple and the length of the moment arm for a closure system where the firing and closing systems are separate and distinct. The larger the moment arm of the closure system, the more efficiently it handles clamp loads and tissue compression. However, the distance between the articulation joint and the first staple may have a large impact on the access of the surgical end effector as it is positioned into tight spaces within a laparoscopic environment. 
       FIGS.  25 - 32    illustrate exemplary moment arms for each of the surgical end effectors  1500 ,  3500 ,  5500 ,  7500 . Turning first to  FIG.  25   , as was described above, the anvil trunnions  1822  extend laterally out of each lateral side of the anvil mounting portion  1820  to be received in a corresponding trunnion cradle  1614  formed in the upstanding walls  1612  of the proximal end portion  1610  of the elongate channel  1602 . The anvil trunnions  1822  are pivotally retained in their corresponding trunnion cradle  1614  by the channel cap or anvil retainer  1630 . The channel cap  1630  includes a pair of attachment lugs  1636  that are configured to be retainingly received within corresponding lug grooves or notches  1616  formed in the upstanding walls  1612  of the proximal end portion  1610  of the elongate channel  1602 . Such arrangement constrains the anvil  1810  to only pivot about the pivot axis PA 1  (see  FIG.  3   ). Under such arrangement, the anvil mounting portion  1820  does not move axially or vertically. As the distal closure tube segment  2030  is advanced in the distal direction DD under a horizontal closure force F H1  ( FIG.  26   ), the interaction between an internal cam surface  2036  on the distal closure tube segment  2030  and an anvil cam surface  1821  on the anvil mounting portion  1820  results in the application of a closure force F C1  to the anvil cam surface  1821 . The closure force F C1  comprises the resultant force of the horizontal closure force F H1  and a vertical closure force F V1  and is essentially “normal to” or perpendicular to the cam surface  1821  on the anvil mounting portion  1820 . See  FIG.  26   . M A1  represents a closure moment arm from the anvil pivot axis PA 1  (coincident with the center of anvil trunnions  1822 ) to the point of contact between the internal cam surface  2036  on the distal closure tube segment  2030  and the anvil cam surface  1821  on the anvil mounting portion  1820  when the anvil  1810  has been pivoted to the fully closed position. In one example, the closure moment arm M A1  may be approximately 0.415 inches, for example. M A1 ×F C1 =a closure moment C M1  that is applied to the anvil mounting portion  1820 . 
     To ensure that the each side of the tissue cut line is fastened with staples or fasteners extending from the proximal end to the distal end of the tissue cutline, a proximal end portion  1818  of the anvil body  1812  is formed with two tissue stop formations or tissue locating features  1830  that extend downwardly from each lateral side of the anvil body  1812  (only one tissue stop formation  1830  may be seen in FIGS.  25  and  26 ). When the anvil  1810  is opened to receive the target tissue between the underside of the anvil and the cartridge deck surface, the downwardly extending tissue stop  1830  serve to prevent the target tissue from extending proximally past the proximal most staples/fasteners in the surgical staple/fastener cartridge  1700 . If the tissue were to extend proximally beyond the proximal most staples/fasteners, that portion of tissue may be severed by the firing member during the firing process and may not be fastened which may lead to catastrophic results. The downwardly extending tissue stops  1830  may prevent this from happening. In the embodiment depicted in  FIG.  26   , for example, the proximal-most staple/fastener pockets  1720  are shown in phantom lines relative to the tissue stops  1830 . As can be seen in that Figure, the tissue stop  1830  has a downwardly extending portion  1832  and a chamfered portion  1834 . The target tissue is contacted by the portions  1832 ,  1834  to prevent the target tissue from extending proximally beyond the proximal most staples/fasteners that are supported in the proximal most staple/fastener pockets  1720  in the staple/fastener cartridge body  1702 . 
     Returning again to  FIG.  25   , as the anvil  1810  is pivoted closed onto the target tissue (not shown) that is positioned between the underside or tissue contacting surface  1813  of the anvil body  1812 , the tissue applies tissue forces T F1  to the underside  1813  of the anvil body  1812  which cause the anvil  1810  to experience a tissue counter moment CTS that must be overcome by the closure moment C M1  established by the closure system components. The example depicted in  FIG.  25    illustrates equally distributed tissue forces T F1  on the anvil  1810  and a tissue moment arm M T1  established by the clamped tissue (the clamped tissue is not shown in  FIG.  25    for clarity purposes). As can be seen in that Figure, in that example, the tissue moment arm M T1  is considerably longer than the closure moment arm M A1  (i.e., M T1 &gt;M A1 ). 
     Turning next to  FIGS.  27  and  28   , as was described above, the anvil trunnions  3822  of the anvil  3810  of the interchangeable surgical tool assembly  3000  extend laterally out of each lateral side of the anvil mounting portion  3820  to be received in corresponding trunnion holes  3613  formed in the upstanding walls  3612  of the proximal end portion  3610  of the elongate channel  3602 . Such arrangement constrains the anvil  3810  to only pivot about the anvil pivot axis PA 2  (see  FIG.  18   ). Under such arrangement, the anvil mounting portion  3820  does not move axially or vertically. As the distal closure tube segment  4030  is advanced in the distal direction DD under a horizontal closure force F H2  ( FIG.  28   ), the interaction between an internal cam surface  4036  on the distal closure tube segment  4030  and an anvil cam surface  3821  on the anvil mounting portion  3820  results in the application of a closure force F C2  to the anvil cam surface  3821 . The closure force F C2  comprises the resultant force of the horizontal closure force F H2  and a vertical closure force F V2  and is essentially “normal to” or perpendicular to the anvil cam surface  3821  on the anvil mounting portion  3820 . See  FIG.  28   . M A2  represents the closure moment arm from the anvil pivot axis PA 2  (center of anvil trunnions  3822 ) to the point of contact between the internal cam surface  4036  on the distal closure tube  4030  and the anvil cam surface  3821  on the anvil mounting portion  3820  when the anvil  3810  has been pivoted to the fully closed position. In one example, closure moment arm M A2  may be approximately 0.539 inches, for example. M A2 ×F C2 =a closure moment C M2  that is applied to the anvil mounting portion  3820 . 
     In the example depicted in  FIGS.  27  and  28   , the anvil body  3812  is formed with two tissue stop formations or tissue locating features  3830  that extend downwardly from each lateral side of the anvil body  3812  (only one tissue stop formation  3830  may be seen in  FIGS.  27  and  28   ). When the anvil  3810  is opened to receive the target tissue between the underside of the anvil and the cartridge deck surface, the downwardly extending tissue stop formations  3830  serve to prevent the target tissue from extending proximally past the proximal most staples/fasteners in the surgical staple/fastener/fastener cartridge  3700 . In the embodiment depicted in  FIG.  28   , for example, the proximal-most staple pockets  3720  are shown in phantom lines relative to the tissue stop formations  3830 . As can be seen in that Figure, the tissue stop formation  3830  has a downwardly extending portion  3832  and a chamfered portion  3834 . The target tissue is contacted by the portions  3832 ,  3834  to prevent the target tissue from extending proximally beyond the proximal most staples/fasteners that are supported in the proximal-most staple/fastener pockets  3720  in the staple/fastener cartridge body  3702 . 
     Returning again to  FIG.  27   , as the anvil  3810  is pivoted closed onto the target tissue (not shown) that is positioned between the underside or tissue contacting surface  3813  of the anvil body  3812 , the tissue applies tissue forces T F2  to the underside  3813  of the anvil body  3812  which cause the anvil  3810  to experience a tissue counter moment C T2  that must be overcome by the closure moment C M2  established by the closure system components. The example depicted  FIG.  27    illustrates equally distributed tissue forces T F2  on the anvil  3810  and a tissue moment arm M T2  established by the clamped tissue (the clamped tissue is not shown in  FIG.  27    for clarity purposes). As can be seen in that Figure, in that example, the tissue moment arm M T2  is considerably longer than the closure moment arm M A2  (i.e., M T2 &gt;M A2 ). 
     Turning next to  FIGS.  29  and  30   , as was described above, the anvil trunnions  5822  of the anvil  5810  of the interchangeable surgical tool assembly  5000  extend laterally out of each lateral side of the anvil mounting portion  5820  to be received in the corresponding “open-ended” vertical cradle  5613  formed in the upstanding walls  5612  of the proximal end portion  5610  of the elongate channel  5602 . In this arrangement, the anvil trunnions  5822  are free to pivot within their respective cradles  5613  as the distal closure tube segment  6030  cammingly contacts the anvil cam surface  5821  on the anvil mounting portion  5820 . Under such arrangement, the anvil  5810  does not move axially, but the anvil trunnions  5822  are free to move vertically (arrow V) within their respective cradles  5613 . As the distal closure tube segment  6030  is advanced in the distal direction DD under the horizontal closure force F H3  ( FIG.  30   ), the interaction between an internal cam surface  6036  on the distal closure tube segment  6030  and the anvil cam surface  5821  on the anvil mounting portion  5820  results in the application of a closure force F C3  to the anvil cam surface  5821 . The closure force F C3  comprises the resultant force of the horizontal closure force F H3  and a vertical closure force F V3  and is essentially “normal to” or perpendicular to the anvil cam surface  5821  on the anvil mounting portion  5820 . See  FIG.  30   . M A3  represents the closure moment arm from the anvil pivot axis PA 3  (coincident with the center of anvil trunnions  5822 ) to the point of contact between the internal cam surface  6036  on the distal closure tube  6030  and the anvil cam surface  5821  on the anvil mounting portion  5820  when the anvil  5810  has been pivoted to the closed position. In one example, closure moment arm M A3  may be approximately 0.502 inches, for example. M A3 ×F C3 =a closure moment C M3  that is applied to the anvil mounting portion  5820 . 
     In the example depicted in  FIGS.  29  and  30   , the anvil body  5812  is formed with two tissue stop formations or tissue locator features  5830  that extend downwardly from each lateral side of the anvil body  5812  (only one tissue stop formation  5830  may be seen in  FIGS.  29  and  30   ). When the anvil  5810  is opened to receive the target tissue between the underside of the anvil and the cartridge deck surface, the downwardly extending tissue stop formations  5830  serve to prevent the target tissue from extending proximally past the proximal most staples/fasteners in the surgical staple/fastener cartridge  5700 . In the embodiment depicted in  FIG.  29   , for example, the proximal-most staple/fastener pockets  5720  are shown in phantom lines relative to the tissue stop formations  5830 . As can be seen in that Figure, the tissue stop formation  5830  has a downwardly extending portion  5832  and a chamfered portion  5834 . The target tissue is contacted by the portions  5832 ,  5834  to prevent the target tissue from extending proximally beyond the proximal most staples/fasteners that are supported in the proximal-most staple/fastener pockets  5720  in the staple/fastener cartridge body  5702 . 
     Returning again to  FIG.  29   , as the anvil  5810  is pivoted closed onto the target tissue (not shown) that is positioned between the underside  5813  of the anvil body  5812 , the tissue applies tissue forces T F3  to the underside or tissue contacting surface  5813  of the anvil body  5812  which cause the anvil  5810  to experience a tissue counter moment C T3  that must be overcome by the closure moment C M3  established by the closure system components. The example depicted in  FIG.  29    illustrates equally distributed tissue forces T F3  on the anvil  5810  and a tissue moment arm M T3  established by the clamped tissue (the clamped tissue is not shown in  FIG.  29    for clarity purposes). As can be seen in that Figure, in that example, the tissue moment arm M T3  is considerably longer than the closure moment arm M A3  (i.e., M T3 &gt;M A3 ). 
     Turning now to  FIGS.  31  and  32   , as was described above, the anvil trunnions  7822  of the anvil  7810  of the interchangeable surgical tool assembly  7000  extend laterally out of each lateral side of the anvil mounting portion  7820  to be received in the corresponding “kidney-shaped” opening  7613  formed in the upstanding walls  7612  of the proximal end portion  7610  of the elongate channel  7602 . When the anvil  7810  is in a “fully” open position, the anvil trunnions  7822  may generally be located in the bottom portion  76136  of the kidney slot  7613 . The anvil  7810  can be moved to a closed position by distally advancing the distal closure tube segment  8030  in the distal direction DD so that the internal cam surface  8036  on the distal end  8035  of the distal closure tube segment  8030  rides up an anvil cam surface  7821  that is formed on the anvil mounting portion  7820  of the anvil  7810 . As the internal cam surface  8036  on the distal end  8035  of the distal closure tube segment  8030  is distally advanced along the anvil cam surface  7821  on the anvil mounting portion  7820  under the horizontal closure force F H4  ( FIG.  32   ), the distal closure tube segment  8030  causes the body portion  7812  of the anvil  7810  to pivot and move axially relative to the surgical staple/fastener cartridge  7700  as the anvil trunnions  7822  move upwardly and distally in the kidney slots  7613 . When the distal closure tube segment  8030  reaches the end of its closure stroke, the distal end  8035  of the distal closure tube segment  8030  abuts/contacts an abrupt anvil ledge  7823  and serves to position the anvil  7810  so that the forming pockets (not shown) in the underside or tissue contacting surface  7813  of the body portion  7812  are properly aligned with the staples/fasteners in the staple/fastener cartridge  7700 . The anvil ledge  7823  is defined between the anvil cam surface  7821  on the anvil mounting portion  7820  and the anvil body portion  7812 . Stated another way, in this arrangement, the anvil cam surface  7821  does not extend to an outermost surface  7817  of the anvil body  7812 . When in that position, the anvil trunnions  7822  are located at top portions  7613 T of the kidney slots  7613 . M A4  represents the moment arm from the anvil pivot axis PA 4  (coincident with the center of the anvil trunnions  7822 ) when the trunnions  7822  are located in the top portions  7613 T of the kidney slots  7613  as shown. In one example, the moment arm M A4  may be approximately 0.184 inches, for example. M A4 ×F H4 =a closure moment C M4  that is applied to the anvil mounting portion  7820 . 
     In the example depicted in  FIGS.  31  and  32   , the anvil body  7812  is formed with two tissue stop formations or tissue locator formations  7830  that extend downwardly from each lateral side of the anvil body  7812  (only one tissue stop formation  7830  may be seen in  FIGS.  31  and  32   ). When the anvil  7810  is opened to receive the target tissue between the underside of the anvil and the cartridge deck surface, the downwardly extending tissue stop formations  7830  serve to prevent the target tissue from extending proximally past the proximal most staples/fasteners in the surgical staple/fastener cartridge  7700 . In the embodiment depicted in  FIG.  31   , for example, the proximal most staple/fastener pockets  7720  are shown in phantom lines relative to the tissue stop formations  7830 . As can be seen in that Figure, the tissue stop formation  7830  has a downwardly extending portion  7832  and a chamfered portion  7834 . The target tissue is contacted by the portions  7832 ,  7834  to prevent the target tissue from extending proximally beyond the proximal most staples/fasteners that are supported in the proximal most staple/fastener pockets  7720  in the staple/fastener cartridge body  7702 . 
     Returning again to  FIG.  31   , as the anvil  7810  is pivoted closed onto the target tissue (not shown) that is positioned between the underside or tissue contacting surface  7813  of the anvil body portion  7812 , the tissue applies tissue forces T F4  to the underside  7813  of the anvil body  7812  which cause the anvil  7810  to experience a tissue counter moment C T4  that must be overcome by a closure moment C M4  established by the closure system components. The example depicted  FIG.  31    illustrates equally distributed tissue forces T F4  on the anvil  7810  and a tissue moment arm M T4  established by the clamped tissue (the clamped tissue is not shown in  FIG.  31    for clarity purposes). As can be seen in that Figure, in that example, the tissue moment arm M T4  is considerably longer than the closure moment arm M A4  (i.e., M T4 &gt;M A4 ). 
     The illustrated exemplary interchangeable surgical tool assemblies  1000 ,  3000 ,  5000 ,  7000  comprise surgical stapling devices that employ “separate and distinct” closure and firing systems. That is, the closure system employed to close the jaws is separately actuatable from the firing system used to drive the firing member through the surgical staple/fastener cartridge to cut and fasten tissue. These separate and distinct closure and firing systems may be distinguishable from those surgical stapling instruments wherein actuation of the firing system to advance the firing member is required to move the jaws from an open position to a closed position. As will be discussed in further detail below, however, the firing members of some of the interchangeable surgical tool assemblies disclosed herein may also apply additional closure motions to the anvil as the firing member is fired (i.e., distally advanced through the surgical end effector). As can be seen from reference to  FIGS.  25 - 32   , in the illustrated examples, M A2 &gt;M A3 &gt;M A1 &gt;M A4 .  FIGS.  25 ,  27 ,  29  and  31    also illustrate the resistive forces established by the tissue during the closure process. T F  represents the force generated by the tissue when the tissue is clamped between the anvil and the staple cartridge. These forces establish a “counter” moment C T  that is applied to the anvil about the point/area where the distal closure tube segment is in camming contact with the anvil cam surface on the anvil mounting portion. In these illustrated examples, the tissue moment arm for each surgical instrument (tool assembly) is generally larger than the closure moment arm for that instrument. It may be appreciated from the difference between a typical tissue moment arm encountered when clamping tissue between the anvil and the surgical staple/fastener cartridge and the closure moment arm of the instrument results in the need for sufficient closure forces to be applied by the distal closure tube segment to the anvil in order to sufficiently close the anvil onto the tissue. Thus, the distal closure tube segment must be sufficiently strong and robust to handle the considerable stresses formed therein during the closure process. To establish a stress state in the distal closure tube segment that more closely resembles a “hoop stress” state instead of a “ring stress” state, the sidewalls of the distal closure tube segment may be thickened so as to contact the side walls and anvil mounting portions of the corresponding elongate channel. Such arrangement may also add strength to the overall hoop-like structure of the tube. Maximizing the thickness on the anvil side of the distal closure tube segment may also improve the strength of the tube segment (hoop) while allowing room for a large bearing or cam surface to cam the anvil downward towards the cartridge. U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950, discloses several distal closure tube segment configurations which may be employed in the various interchangeable surgical tool assemblies disclosed herein. 
     The forgoing discussion and comparisons may illustrate that closure system designs that have large closure moment arms may lead to improved efficiencies of the closure system components and can reduce the amount of closure forces that are required to achieve full anvil closure onto the tissue. However, as noted above, there may be tradeoffs with other design variables when attempting to maximize the closure moment arm. For example, another desirable attribute relates to “jaw aperture”. “Jaw aperture” may refer to a distance J A  which is measured from the middle of a distalmost staple or fastener center along a line that is perpendicular to the corresponding distalmost staple forming pocket on the underside or tissue contact surface of the anvil body portion.  FIG.  33    illustrates the jaw aperture J A1  for the surgical end effector  1500 . In the illustrated example, the distalmost staple/fastener pockets  1730  contain the distalmost staples or fasteners (not shown) therein. Each distalmost staple or fastener corresponds to a distalmost staple/fastener forming pocket  1815  (shown in phantom in  FIG.  33   ) that is formed in the underside or tissue contacting surface  1813  of the anvil body  1812 . The distance J A1  between the distalmost staple/fastener pocket  1730  and the corresponding distalmost staple/fastener forming pocket  1815  is the “jaw aperture” for the surgical end effector  1500 . In at least one embodiment, for example, J A1  is approximately 1.207 inches.  FIG.  34    illustrates the jaw aperture J A2  for the surgical end effector  3500 . In the illustrated example, the distalmost staple/fastener pockets  3730  contain the distalmost staples or fasteners (not shown) therein. Each distalmost staple or fastener corresponds to a distalmost staple/fastener forming pocket  3815  that is formed in the underside or tissue contact surface  3813  of the anvil body  3812 . The distance J A2  between the distalmost staple/fastener pocket  3730  and the corresponding distalmost staple/fastener forming pocket  3815  is the “jaw aperture” for the surgical end effector  3500 . In at least one embodiment, for example, J A2  is approximately 0.781 inches.  FIG.  35    illustrates the jaw aperture J A3  for the surgical end effector  5500 . In the illustrated example, the distalmost staple/fastener pockets  5730  contain the distalmost staples/fasteners (not shown therein). Each distalmost staple/fastener corresponds to a distalmost staple/fastener forming pocket  5815  that is formed in the underside or tissue contact surface  5813  of the anvil body  5812 . The distance J A3  between the distalmost staple/fastener pocket  5730  and the corresponding distalmost staple/fastener forming pocket  5815  is the “jaw aperture” for the surgical end effector  5500 . In at least one embodiment, for example, J A3  is approximately 0.793 inches.  FIG.  36    illustrates the jaw aperture J A4  for the surgical end effector  7500 . In the illustrated example, the distalmost staple/fastener pockets  7730  contain the distalmost staples or fasteners (not shown) therein. Each distalmost staple or fastener corresponds to a distalmost staple/fastener forming pocket  7815  that is formed in the underside or tissue contact surface  7813  of the anvil body  7812 . The distance J A4  between the distalmost staple/fastener pocket  7730  and the corresponding distalmost staple/fastener forming pocket  7815  is the “jaw aperture” for the surgical end effector  7500 . In at least one embodiment, for example, J A4  is approximately 0.717 inches. Thus, for these examples, J A1 &gt;J A3 &gt;J A2 &gt;J A4 . As such, comparatively, surgical end effector  1500  has the greatest jaw aperture. 
     In those surgical end effector designs that employ separate and distinct closure and firing systems that utilize an axially movable closure ring or distal closure tube segment such as the examples described above, the interrelationships between the anvil or jaw pivot axis PA and the distal end of the distal closure tube segment as well as the robustness of the anvil mounting portion may determine the magnitude of the jaw aperture that is attainable for each specific end effector design. These interrelationships may be better appreciated from reference to  FIG.  37   , for example.  FIG.  37    depicts a surgical end effector  1500 R that employs an anvil  1810 R that has an anvil mounting portion  1820 R that is shown in solid lines. The anvil mounting portion  1820 R includes anvil trunnions  1822 R that define a reference pivot axis P AR  about which the anvil mounting portion  1820 R may pivot relative to an elongate channel  1602 R. The surgical end effector  1500 R also employs a distal closure tube segment  2030 R that has a distal end  2035 R that is configured to cammingly contact the anvil mounting portion  1820 R in the various manners discussed above. A surgical staple/fastener cartridge  1700 R is supported in the elongate channel  1602 R and has a cartridge deck surface or tissue contact surface  1710 R.  FIG.  37    depicts a distance D P  between the reference pivot axis P AR  and the distal end  2035 R of the distal closure tube segment  2030 R.  FIG.  37    illustrates the anvil  1810 R in solid lines. The anvil body  1812 R is in its maximum open position when the distal closure tube segment  2030 R is in its proximal most starting position relative to the anvil mounting portion  1820 R. The maximum aperture angle APA R  for that configuration is approximately ten degrees, for example. This aperture angle APA R  is typical for many end effector arrangements. In another end effector arrangement, the aperture angle is 12.25 degrees. In one arrangement, for example, D P  may be approximately 0.200 inches. To attain a larger aperture angle APA R1  of, for example, twenty-two degrees, if the relationship between the distal end  2035 R of the distal closure tube segment  2030 R and the reference pivot axis P AR  remains unchanged, then a cross-sectional width Mw of an anvil mounting portion  1820 R 1  must undesirably be decreased. The anvil  1810 R 1  is illustrated in phantom lines. As can be seen in that Figure, an abrupt ledge must be formed between the anvil body  1812 R 1  and the anvil mounting portion  1820 R 1  such that the cross-sectional width thereof is reduced. The aperture angle APA R1  is measured from the underside  1813 R 1  of the anvil body  1812 R 1  and the deck surface  1710 R of the surgical staple/fastener cartridge  1700 R. Such reduction in robustness of the anvil mounting portion of the anvil may lead to reduced anvil reliability and is less desirable than anvils that have anvil mounting portions with larger cross-sectional profiles. 
     Referring now to  FIGS.  38  and  39   , increases in jaw aperture (or aperture angle) may be more easily achieved as the pivot or pivot axis PA moves closer to the distal end of the starting or proximal position of the distal closure tube segment.  FIG.  38    illustrates a surgical end effector  1500 ′ that is substantially similar to surgical end effector  1500 , except for the location of the pivot axis PA′ relative to the distal end  2035  of the distal closure tube segment  2030 . As can be seen in that Figure, the distance between the pivot axis PA′ and the distal end  2035  of the distal closure tube segment  2030  when the distal closure tube segment  2030  is in its proximal-most starting position is represented by DP′ and the aperture angle is APA. Stated another way, when the distal closure tube segment  2030  is in its starting position that corresponds with the fully open position of the anvil  1810 , the distal end  2035  thereof is on a reference plane RF that is perpendicular to said shaft axis SA. The distance between the pivot axis PA′ and the reference plane RF′ measured along a line that is perpendicular to the reference plane RF′ and extends through the pivot axis PA′ is DP′. In at least one arrangement, DP′ is approximately 0.200 inches and the aperture angle APA may be approximately 10°. 
       FIG.  38    illustrates the aperture angle APA of a surgical end effector  1500 ′ with a distance DP′ between the reference pivot axis PA′ and the distal end  2035  of the distal closure tube segment  2030 . Turning next to  FIG.  39   , as can be seen in that Figure, the distance DP between the pivot axis PA and the reference plane RF upon which the distal end  2035  of the distal closure tube segment  2030  is located when the distal closure tube segment  2030  is in its proximal most starting position is less than distance DP′ and the aperture angle APA 1  is greater than APA. For example, in at least one embodiment, the distance DP is approximately 0.090 inches and the aperture angle APA 1  is approximately twenty two degrees. Thus, by moving the pivot axis PA closer to the distal end of the distal closure tube segment when the distal closure tube segment is in its proximal most starting position, the jaw aperture may be significantly increased without the need to reduce the cross-sectional width of the anvil mounting position. This may represent a significant improvement over other surgical end effector arrangements. In various circumstances, the center of the anvil trunnions  1822  may ideally be located between 0.010-0.060 inches from the distal end  2035  of the distal closure tube segment  2030  when the distal closure tube segment is in the starting (proximal most) position. A maximum distance for large jaw aperture applications may be, for example, 0.090 inches. As can also be seen in  FIG.  39   , when the anvil  1810  is in its fully open position as shown, the downwardly extending portion  1832  of the tissue stop  1830  generally stops at the staple cartridge deck surface  1710  to prevent any proximal movement of the target tissue during clamping. 
       FIGS.  40  and  41    illustrate tissue stop or tissue locator arrangements  1830  employed on one form of the surgical end effector  1500 . As indicated above, the tissue stops  1830  comprise a downwardly extending portion  1832  and a chamfered portion  1834 . The downwardly extending portion  1832  comprises a distal edge  1833  that terminates in a distal corner portion  1835 .  FIG.  40    illustrates the anvil  1810  in its fully open position. The underside  1813  of the anvil body  1812  is positioned at an aperture angle APA 1 . In at least one arrangement, the aperture angle APA 1  is greater than 12.25 degrees (12.25°) and may be as large as eighteen degrees (18°). When in that fully open position, the surgical end effector  1500  may further have a proximal aperture P APP1  that in at least one arrangement may be approximately 0.254 inches, for example. The proximal aperture defines how much tissue can be positioned between the proximal portions of the jaws (anvil and cartridge). A large proximal aperture may be most advantageous, for example, when cutting and fastening lung tissue which may be partially inflated when being introduced between the anvil and cartridge. The proximal aperture may be measured from the center of the proximal most fastener pocket or pocket pair directly vertical to the underside or tissue contact surface on the anvil body. 
     When the anvil  1810  is in the fully opened position as shown in  FIG.  40   , the distal corner  1835  does not extend above the cartridge deck surface  1710  so as to prevent tissue from moving proximal to the proximal most staples in the proximal most staple pockets  1720 . In at least one embodiment, an upstanding channel stop portion  1619  may extend upwardly from the side walls of the elongate channel  1602  so as to coincide with each corresponding tissue stop  1830  to further prevent any proximal infiltration of tissue between the tissue stop  1830  and the channel stop portion  1619 .  FIG.  41    illustrates the anvil  1810  in a fully closed position. When in that position, the distal edges  1833  of the tissue stops  1830  are approximately aligned or coincident with the locations of the proximal most staples/fasteners in the staple/fastener cartridge  1700 . The distance from the articulation axis AA 1  to the proximal most staples/fasteners is identified as T SD1 . In one arrangement, T SD1  is approximately 1.044 inches, for example. When the anvil  1810  is fully closed, the tissue stops  1830  may be sized and shaped relative to the proximal end portion  1610  of the elongate channel  1602  so as to facilitate easy insertion through a correspondingly sized standard trocar. In at least one example, the tissue stops  1830  of the anvil  1810  are sized and shaped relative to the elongate channel  1602  so as to permit the surgical end effector  1500  to be inserted through a conventional 12 mm trocar. 
       FIGS.  42  and  43    illustrate tissue stop arrangements  3830  employed on one form of the surgical end effector  3500 . As indicated above, the tissue stops  3830  comprise a downwardly extending portion  3832  and a chamfered portion  3834 . The downwardly extending portion  3832  comprises a distal edge  3833  that terminates in a distal corner portion  3835 .  FIG.  42    illustrates the anvil  3810  in its fully open position. The underside  3813  of the anvil body  3812  is positioned at an aperture angle APA 2 . In at least one arrangement, the aperture angle APA 2  is approximately thirteen and one half degrees (13.5°). When in that fully open position, the surgical end effector  3500  may further have a proximal aperture P APP2  that in at least one arrangement may be approximately 0.242 inches, for example. When the anvil  3810  is in the fully opened position as shown in  FIG.  42   , the distal corner  3835  does not extend above the cartridge deck surface  3710  so as to prevent tissue from moving proximal to the proximal most staples/fasteners in the proximal most staple/fastener pockets  3720 .  FIG.  43    illustrates the anvil  3810  in a fully closed position. When in that position, the distal edges  3833  of the tissue stops  3830  are approximately aligned or coincident with the locations of the proximal most staples/fasteners in the staple/fastener cartridge  3700 . The distance from the articulation axis AA 2  to the proximal most staples/fasteners is identified as T SD2 . In one arrangement, T SD2  is approximately 1.318 inches, for example. 
       FIGS.  44  and  45    illustrate tissue stop arrangements  5830  employed on one form of the surgical end effector  5500 . As indicated above, the tissue stops  5830  comprise a downwardly extending portion  5832  and a chamfered portion  5834 . The downwardly extending portion  5832  comprises a distal edge  5833  that terminates in a distal corner portion  5835 .  FIG.  44    illustrates the anvil  5810  in its fully open position. The underside  5813  of the anvil body  5812  is positioned at an aperture angle APA 3 . In at least one arrangement, the aperture angle APA 3  is approximately eight degrees (8°). When in that fully open position, the surgical end effector  5500  may further have a proximal aperture P APP3  that in at least one arrangement may be approximately 0.226 inches, for example. When the anvil  5810  is in the fully opened position as shown in  FIG.  44   , the distal corner  3835  extends slightly above the cartridge deck surface  5710 .  FIG.  45    illustrates the anvil  5810  in a fully closed position. When in that position, the distal edges  5833  of the tissue stops  5830  are approximately aligned or coincident with the locations of the proximal most staples/fasteners in the staple/fastener cartridge  5700 . The distance from the articulation axis AA 3  to the proximal most staples/fasteners is identified as T SD3 . In one arrangement, T SD3  is approximately 1.664 inches, for example. 
       FIGS.  46  and  47    illustrate tissue stop arrangements  7830  employed on one form of the surgical end effector  7500 . As indicated above, the tissue stops  7830  comprise a downwardly extending portion  7832  and a chamfered portion  7834 . The downwardly extending portion  7832  comprises a distal edge  7833  that terminates in a distal corner portion  7835 .  FIG.  46    illustrates the anvil  7810  in its fully open position. The underside  7813  of the anvil body portion  7812  is positioned at an aperture angle APA 4 . In at least one arrangement, the aperture angle APA 4  is approximately ten degrees (10°). When in that fully open position, the surgical end effector  7500  may further have a proximal aperture P APP4  that in at least one arrangement may be approximately 0.188 inches, for example. When the anvil  7810  is in the fully opened position as shown in  FIG.  46   , the distal corner portion  7835  extends slightly below the cartridge deck surface  7710  so as to prevent tissue from getting proximal to the proximal most staples/fasteners in the proximal most staple pockets  7720 .  FIG.  47    illustrates the anvil  7810  in a fully closed position. When in that position, the distal edges  7833  of the tissue stops  7830  is approximately aligned or coincident with the locations of the proximal most staples/fasteners in the staple/fastener cartridge  7700 . The distance from the articulation axis AA 4  to the proximal most staples/fasteners is identified as T SD4 . In one arrangement, T SD4  is approximately 1.686 inches, for example. 
     In various circumstances, the relationships of the firing member to the articulation axis AA as well as to the jaw pivot axis PA about which the anvil pivots may bear upon the length of the articulation joint arrangement. Of course, longer articulation joint arrangements may detrimentally affect the end effector&#39;s maneuverability within tight spaces and also limit the magnitude of the jaw aperture that may ultimately be obtained by the end effector.  FIG.  48    illustrates the surgical end effector  1500  in a fully open position. That is, the anvil  1810  has been pivoted to its fully open position and the firing member  2140  is in its home or starting position. The distance between the distal end of each of the anvil engagement features  2147  and the articulation axis AA 1  is represented by AJD 1 . In at least one example, AJD 1  is approximately 0.517 inches. By way of comparison and turning to  FIG.  49   , the distance AJD 2  from the distal end of each of the anvil engagement features  4147  and the articulation axis AA 2  is, in at least one example, is approximately 0.744 inches. Referring to  FIG.  50   , the distance AJD 3  from the distal end of each of the anvil engagement features  6147  and the articulation axis AA 3  is, in at least one example, is approximately 1.045 inches. Turning to  FIG.  51   , the distance AJD 4  from the distal end of each of the anvil engagement features  8147  and the articulation axis AA 4  is, in at least one example, is approximately 1.096 inches. Thus, as can be seen from this comparison, the articulation joint arrangement (as measured by distances AJD 1 , AJD 2 , AJD 3 , AJD 4 ) of the surgical end effector  1500  is more compact and thus may be more maneuverable than the surgical end effectors  3500 ,  5500  and  7500  in at least some surgical applications. 
     Another factor that may affect the length of the joint arrangement relates to the location of the firing member relative to the anvil pivot axis PA about which the anvil pivots. For example,  FIG.  52    illustrates the anvil  1810  of surgical end effector  1500  in its fully open position. When in that position, the firing member  2140  is in its parked or “starting position”. As can be seen in that Figure, one useful metric for comparing the “compactness” of the articulation joint arrangement is the proximal tab distance TD 1  between the proximal end  2149  of each of the top anvil engagement features  2147  and the anvil pivot axis PA 1 . In at least one preferred arrangement, the proximal tab distance TD 1  is approximately greater than thirty-five percent (35%) of the overall length TL 1  of each of the anvil engagement features  2147  when the anvil  1810  is in a fully open position and the firing member  2140  is in its proximal most or starting position. Stated another way, when the anvil  1810  and the firing member  2140  are in the above described positions, at least 35% of each of the anvil engagement features  2147  extends proximally past the anvil pivot axis PA 1 .  FIG.  53    illustrates the end effector  1500  with the anvil  1810  in the closed position and the firing member  2140  in its proximal most or starting position. As can be seen in that Figure, at least 35% of each of the anvil engagement features  2147  extends proximally past the anvil pivot axis PA 1 . 
       FIG.  54    illustrates the position of the firing member  4140  of the surgical end effector  3500  when the anvil  3810  is in its fully open position and the firing member  4140  is in its proximal most or starting position. As can be seen in that Figure, each of the anvil engagement features  4147  are completely distal to the anvil pivot axis PA 2  thereby resulting in a longer articulation joint arrangement. Thus, the distance TD 2 , is the distal distance between the proximal ends  4149  of the anvil engagement features  4147  and the anvil pivot axis PA 2 .  FIG.  55    illustrates the position of the firing member  6140  of the surgical end effector  5500  when the anvil  5810  is in its fully open position and the firing member  6140  is in its proximal most or starting position. As can be seen in that Figure, each of the anvil engagement features  6147  are completely distal to the anvil pivot axis PA 3  thereby resulting in a longer articulation joint arrangement. Thus, the distance TD 3 , is the distal distance between the proximal ends  6149  of the anvil engagement features  6147  and the anvil pivot axis PA 3 .  FIG.  56    illustrates the position of the firing member  8140  of the surgical end effector  7500  when the anvil  7810  is in its fully open position and the firing member  8140  is in its proximal-most or starting position. As can be seen in that Figure, each of the anvil engagement features  8147  are completely distal to the anvil pivot axis PA 4  thereby resulting in a longer articulation joint arrangement. Thus, the distance TD 4 , is the distal distance between the proximal ends  8149  of the anvil engagement features  8147  and the anvil pivot axis PA 4 . For comparison purposes, the surgical end effector  1500  is the only surgical end effector wherein a portion of the anvil engagement features on the firing member extend proximally past the anvil pivot axis when the firing member is in its proximal most or starting position. The anvil engagement features of each of the firing members of the surgical end effectors  3500 ,  5500  and  7500  are completely distal to their respective anvil pivot axes when the firing members are in their proximal most or starting position. Taking this comparison further, for example, the surgical end effector  1500  is the only surgical end effector wherein at least thirty-five percent (35%) of the anvil engagement features reside between the anvil pivot axis and the articulation axis when the firing member is in its starting position and the anvil is fully opened. Similar comparisons may be drawn from comparing the same distances between the location of the lower channel engagement features on the firing member to the jaw pivot axis when the firing member is in its proximal most starting position. 
     Another metric that may be used to assess the compactness of the articulation joint arrangement may comprise comparing the ratio between the distance from the articulation axis to the distal end of the anvil engagement features on the firing member (distances AJD 1 , AJD 2 , AJD 3 , AJD 4 — FIGS.  48 - 51   ) relative to the distance from the articulation axis to the distal edge of the tissue stops or the proximal most staple/fastener (distances TSD 1 , TSD 2 , TSD 3 , TSD 4 — FIGS.  41 ,  43 ,  45 ,  47   ) for each end effector. For example, in a preferred arrangement, AJD/TSD&lt;0.500. The ratio of AJD/TSD may be referred to herein as the “compactness ratio” of that particular surgical end effector. In one arrangement, for example, for end effector  1500 , AJD 1 /TSD 1 =0.517 inches/1.044 inches=0.495. In one illustrated example for end effector  3500 , AJD 2 /TSD 2 =0.744 inches/1.318 inches=0.564. In one illustrated example for end effector  5500 , AJD 3 /TSD 3 =1.045 inches/1.664 inches=0.628. In one illustrated arrangement, AJD 4 /TSD 4 =1.096 inches/1.686 inches=0.650. Thus, in at least one preferred arrangement wherein the articulation joint arrangement is the most compact, has the largest jaw aperture and is the most maneuverable, the ratio between the distance from the articulation axis to the proximal end of the anvil engagement features on the firing member and the distance from the articulation axis to the distal edge of the tissue stops or the proximal most staple/fastener is approximately less than 0.500. 
       FIGS.  57 - 61    illustrate a progressive closure arrangement for moving the anvil  1810  of the surgical end effector  1500  from a fully open position to a closed position and then to an over closed position.  FIGS.  57  and  58    illustrate the anvil  1810  in a closed position. In both of those Figures, the distal closure tube segment  2030  has been advanced in the distal direction DD to its fully closed position. As was discussed above, the interaction between an internal cam surface  2036  on the distal closure tube segment  2030  and an anvil cam surface  1821  on the anvil mounting portion  1820  causes the anvil  1810  to pivot to the closed position. As can be seen in  FIG.  58   , the staple forming underside or tissue contacting surface  1813  of the anvil body  1812  may be relatively parallel and spaced relative to the cartridge deck surface  1710  of the surgical staple/fastener cartridge. When in that initial closed position, the firing member  2140  is in its starting position as can be seen in  FIG.  57   . When in that position, the anvil engagement features  2147  of the firing member  2140  have not engaged the anvil  1810  but are in substantial horizontal alignment with the ledges  1816  formed in the anvil  1810 . In at least one arrangement, a ramp segment  1829  is formed proximal to each of the horizontal anvil ledges  1816 .  FIG.  59    illustrates the position of the firing member  2140  after it has been distally advanced to a point wherein the anvil engagement features  2147  have initially engaged the horizontal anvil ledges  1816  on the anvil  1810  and  FIG.  61    illustrates the position of the firing member  2140  and the anvil  1810  such that the anvil engagement features are in full engagement with the anvil ledges  1816  to apply an “overclosure” force to the anvil  1810  as the firing member  2140  continues to be distally advanced. In at least one arrangement as illustrated in  FIG.  61   , for example, when the anvil  1810  is in the over closed position (with no tissue being clamped between the anvil and the cartridge), the distal portion of the anvil  1810  will contact with the cartridge deck surface  1710 . As a result of such configuration, the force required to distally advance the firing member from its starting position to its ending position within the end effector may generally be less than other surgical end effector arrangements that do not employ such progressive closure arrangements. 
       FIG.  62    illustrates the anvil  1810  of the surgical end effector  1500  in a fully opened position. As was discussed above, each of the anvil trunnions  1822  are received in a corresponding trunnion cradle  1614  that is formed in the upstanding walls  1612  of the proximal end portion  1610  of the elongate channel  1602 . The anvil trunnions  1822  are pivotally retained in their corresponding trunnion cradle  1614  by the channel cap or anvil retainer  1630 . The channel cap  1630  includes a pair of attachment lugs  1636  that are configured to be retainingly received within corresponding lug grooves or notches  1616  formed in the upstanding walls  1612  of the proximal end portion  1610  of the elongate channel  1602 . During a portion of the closure stroke for the anvil  1810  on thick tissue, counterforces established during the tissue clamping process seek to push the anvil trunnions  1822  out of their respective trunnion cradles  1614 . The channel cap  1630  includes a pair of slot cap portions  1632  that correspond to each trunnion cradle  1614 . When the channel cap  1630  is installed onto the proximal end portion  1610  of the elongate channel  1602 , each slot cap portion  1632  serves to retain the anvil trunnions  1822  within their respective trunnion cradles  1614  during the closure process. As can be seen in  FIGS.  62  and  63   , each slot cap portion  1632  may have an arcuate bottom portion  1638  that is configured to pivotally receive the corresponding anvil trunnion  1822 . Each slot cap  1632  may have a wedge shape to completely block the open end of the trunnion cradles  1614 . Such channel cap arrangement  1630  may facilitate ease of assembly of the anvil  1810  to the elongate channel  1602 . Once the anvil trunnions  1822  have been placed into their respective trunnion cradles  1614 , the channel cap  1630  may then be installed as shown. In at least one arrangement, the distal closure tube segment  2030  serves to retain the channel cap  1630  in position which serves to prevent the anvil trunnions  1822  from moving vertically in their respective trunnion cradles  1614  during closure as shown in  FIG.  63   . In another arrangement, the attachment lugs  1636  may be frictionally retained within their respective notches  1616  or otherwise be retained therein by adhesive or other fastening means. 
     The four interchangeable tool assemblies  1000 ,  3000 ,  5000  and  7000  employ different jaw opening configurations to facilitate moving the anvil from a closed position to a fully open position. For example, the distal closure tube segment  4030  of the interchangeable tool assembly  3000  includes positive jaw or anvil opening features  4040  that correspond to each of the sidewalls of the distal closure tube segment  4030  and protrude inwardly therefrom. The positive anvil opening features  4040  extend inwardly through corresponding openings in the transitional sidewalls and may be welded to the distal closure tube segment  4030 . In this arrangement, the positive anvil opening features are axially aligned with each other and are configured to operably interface with corresponding opening ramps formed on the undersides of the anvil mounting portion  3820 . When the anvil  3810  and the distal closure tube segment  4030  are in their fully closed positions, each of the positive anvil opening features  4040  is located in a cavity that is established between the anvil opening ramps and the bottom portion of the elongate channel  3602 . When in that position, the positive anvil opening features  4040  do not contact the anvil mounting portion  3820  or at least may not apply any significant opening motions or forces thereto. When the distal closure tube segment  4030  is moved in the proximal direction, the anvil opening features  4040  are brought into contact with the anvil opening ramps to cause the anvil  3810  to pivot to an open position. Further details regarding the positive anvil opening features  4040  may be found in U.S. patent application Ser. No. 15/385,911, entitled SURGICAL STAPLE/FASTENERS WITH INDEPENDENTLY ACTUATABLE CLOSING AND FIRING SYSTEMS, now U.S. Pat. No. 10,448,950. 
     With regard to the surgical end effector  5500  of tool assembly  5000 , the distal closure tube segment  6030  includes two inwardly extending positive anvil opening tabs  6038  that may be punched into the wall of the distal closure tube segment  6030 . See  FIG.  21   . In the illustrated arrangement, the tabs  6038  are axially aligned with each other and are configured to contact corresponding upstanding anvil tails  5827  formed on the anvil mounting portion  5820 . When the distal closure tube segment  6030  is moved in the proximal direction, the anvil opening features  6038  are brought into contact with the anvil tails  5827  to cause the anvil  5810  to pivot to an open position. 
     With regard to the surgical end effector  7500  of the tool assembly  7000 , a positive anvil opening motion is applied to the anvil  7810  by the distal closure tube segment  8030  when the distal closure tube segment  8030  is moved proximally. As was discussed above, an upstanding anvil tab  7824  is formed on the anvil mounting portion  7820  and extends into the horseshoe-shaped opening  8038  in the distal closure tube segment  8030 . See  FIG.  24   . Opening  8038  defines an opening tab  8039  that is configured to operably interface with the anvil tab  7824  as the distal closure tube segment  8030  is retracted in the distal direction. Such interaction between the opening tab  8039  and the anvil tab  7824  applies an opening motion to the anvil  7810  to thereby cause the anvil  7810  to move to an open position. 
     With regard to surgical end effector  1500  of the interchangeable tool assembly  1000 , in the illustrated example, the distal closure tube segment  2030  employs two axially offset, proximal and distal positive jaw opening features  2040  and  2050  as illustrated in  FIGS.  64 - 77   . As can be seen in  FIGS.  64  and  65   , the proximal positive jaw opening feature  2040  is axially proximal to the distal positive jaw opening feature  2050  by an axial offset distance AOF. In  FIG.  65   , the proximal positive jaw opening feature  2040  is located on the right side (as viewed by a user of the tool assembly) of the shaft axis SA 1 .  FIGS.  66 ,  72  and  73    illustrate the position of the proximal positive jaw opening feature  2040  when the anvil  1810  is in the closed position. As can be most particularly seen in  FIG.  66   , when in that position, the proximal positive jaw opening feature  2040  is in a right side or first relieved area  1825  formed in the anvil mounting portion  1820 .  FIGS.  69 ,  72  and  73    illustrate the position of the distal positive jaw opening feature  2050  when the anvil  1810  is in the closed position. As can be most particularly seen in  FIG.  69   , when in that position, the distal positive jaw opening feature is in contact with a stepped portion  1823  of the anvil cam surface  1821 . 
     To commence the opening process, the jaw closure system is actuated to move the distal closure tube segment  2030  in the proximal direction PD. As the distal closure tube segment  2030  is moved in the proximal direction PD, the proximal positive jaw opening feature  2040  contacts a first or right side jaw opening cam surface  1826  and begins to apply a jaw opening motion to the anvil  1810 . See  FIGS.  67 ,  74  and  75   . As can be seen in  FIGS.  70 ,  74  and  75   , during this proximal movement of the distal closure tube segment  2030 , the distal positive jaw opening feature  2050  is axially movable within a second or left relief area  1840  formed in the anvil mounting portion  1820 . Thus, while the proximal positive jaw opening feature  2040  is applying a first or initial opening motion to the anvil mounting portion  1820 , the distal positive jaw opening feature  2050  is not applying any significant opening motion to the anvil  1810 . Further proximal motion of the distal closure tube segment  2030  will result in the distal positive jaw opening feature  2050  contacting a left anvil open tab  1842  and the proximal positive jaw opening feature  2040  disengaging the jaw opening cam surface  1826 . Thus, the proximal positive jaw opening feature  2040  has disengaged the anvil mounting portion  1820  and is not applying any further opening motion thereto while the distal positive jaw opening feature  2050  is applying a second jaw opening motion to the anvil mounting portion  1820  to pivot the anvil  1810  to a fully open position illustrated in  FIGS.  68 ,  71 ,  76  and  77   . 
       FIG.  78    depicts the anvil or jaw opening process employed by the interchangeable tool assembly  1000  in graphical form. As can be seen in that Figure, the left or vertical axis of the graph represents the amount of jaw aperture from about 0° to about 22° (“anvil aperture angle”) and the bottom or horizontal axis represents the approximate proximal axial travel of the distal closure tube segment  2030  from a position wherein the anvil is fully closed to a position wherein the anvil is fully open. As indicated above, the “anvil aperture angle” or “jaw aperture angle” may represent the angle between the cartridge deck surface or tissue contacting surface on the surgical fastener cartridge or “first jaw” and the fastener forming surface or tissue contacting surface on the anvil or “second jaw”. When the anvil is fully closed, the anvil aperture angle may be approximately 0°, for example. In the illustrated arrangement, the distal closure tube segment  2030  can move proximally from a first position ( 1850  on the graph) that corresponds to the fully closed position a proximal distance of, for example, about 0.040 inches to a first intermediate position ( 1852  on the graph) before the proximal positive jaw opening feature  2040  begins to apply a first jaw opening motion to the anvil  1810 . As the distal closure tube segment  2030  continues to move proximally from the first intermediate position  1852  to a second intermediate position ( 1854  on the graph) a further proximal distance of, for example, about 0.040 inches to about 0.120 inches, the proximal positive jaw opening feature  2040  moves the anvil  1810  through an anvil aperture angle from 0° to about 10°. While the distal closure tube segment  2030  continues to travel proximally from the second intermediate position  1854  to a third intermediate position ( 1856  on the graph) a further proximal distance (from about 0.120 inches to about 0.140 inches), the anvil remains at about a 10° anvil aperture angle. Further proximal movement of the distal closure tube segment  2030  from the third intermediate position  1856  to a fourth intermediate position ( 1858  on the graph) a proximal distance (from about 0.140 inches to about 0.240 inches), the distal positive jaw opening feature  2050  begins to apply a second jaw opening motion to the anvil  1810 . As the distal closure tube segment  2030  continues to move proximally from the third intermediate position  1856  to a fourth intermediate position ( 1858  on the graph) a further proximal distance (from, for example, about 0.140 inches to about 0.240 inches), the distal positive jaw opening feature  2050  moves the anvil  1810  relative to the elongate channel  1602  such that the anvil aperture angle increases from about 10° to about 22°, for example. While the distal closure tube segment  2030  continues to travel proximally from the fourth intermediate position  1858  to a final proximal position ( 1860  on the graph) a further proximal distance (from about 0.240 inches to about 0.260 inches, for example), the anvil  1810  remains at a fully open position with an anvil aperture angle of approximately 22°. 
     The closure process of the illustrated example of the interchangeable tool assembly  1000  may be understood from reference to  FIGS.  67 - 69  and  70 - 72   , as well as  FIG.  78   .  FIGS.  68  and  71    illustrate the anvil  1810  in its fully open position. As can be seen in those Figures, the proximal positive jaw opening feature  2040  is out of contact with the anvil mounting portion  1820  and the distal positive jaw opening feature  2050  is in contact with the left anvil open tab  1842 . When the anvil closure process is commenced, the closure drive system is actuated to move the distal closure tube segment  2030  in the distal direction DD. As the distal closure tube segment moves from the final proximal position  1860  to the fourth intermediate position  1858  ( FIG.  78   ), the anvil  1810  remains in its fully open position. Thus, once the closure process is commenced, in at least one example, the distal closure tube segment  2030  may move distally a first or initial predetermined axial closure distance before the anvil  1810  begins to move. Stated another way, the distal closure tube segment may move the first predetermined axial closure distance before any closure motion is applied to the anvil  1810 . In at least one example, the first or initial predetermined closure distance may be approximately 0.020 inches. As the distal closure tube segment  2030  continues to move distally through an intermediate axial closure distance, the distal end  2035  of the distal closure tube segment  2030  begins to contact the anvil cam surface  1821  on the anvil mounting portion  1820  ( FIGS.  67  and  70   ) until the internal cam surface  2036  on the distal closure tube segment  2030  begins to cammingly contact the anvil cam surface  1821 . As the internal cam surface  2036  travels up the anvil cam surface  1821 , the anvil  1810  is pivoted to the fully closed position. The anvil cam surface  1821  and the internal cam surface  2036  may be configured to permit further distal travel of the distal closure tube segment  2030  from, for example, first intermediate point or position  1852  to the first position  1850  ( FIG.  78   ). Thus, in at least one example, the distal closure tube segment  2030  may move distally a final predetermined axial closure distance during the closing process after the anvil  1810  has attained its fully closed position. In at least one example, the final predetermined axial closure distance may be approximately 0.040 inches. 
     In those surgical stapling devices that employ a firing member assembly that comprises a firing member that has a tissue cutting surface, it may be desirable for the firing system and portions of the end effector to be configured in such a way so as to prevent the inadvertent advancement of the firing member unless an unspent staple cartridge is properly supported in the end effector. If, for example, no staple cartridge is present at all and the firing member is distally advanced through the end effector, the tissue would be severed, but not stapled. Similarly, if a spent staple cartridge (i.e., a staple cartridge wherein at least some of the staples have already been fired therefrom) is present in the end effector and the firing member is advanced, the tissue would be severed, but may not be completely stapled, if at all. It will be appreciated that such occurrences could lead to undesirable catastrophic results during the surgical procedure. U.S. Pat. No. 6,988,649 entitled SURGICAL STAPLING INSTRUMENT HAVING A SPENT CARTRIDGE LOCKOUT, U.S. Pat. No. 7,044,352 entitled SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING, U.S. Pat. No. 7,380,695 entitled SURGICAL STAPLING INSTRUMENT HAVING A SINGLE LOCKOUT MECHANISM FOR PREVENTION OF FIRING, U.S. Patent Application Publication No. 2016/0367247, entitled SURGICAL STAPLING INSTRUMENTS WITH LOCKOUT ARRANGEMENTS FOR PREVENTING FIRING SYSTEM ACTUATION WHEN A CARTRIDGE IS SPENT OR MISSING, now U.S. Pat. No. 10,154,841, and U.S. patent application Ser. No. 15/385,958, entitled SURGICAL INSTRUMENTS WITH LOCKOUT ARRANGEMENTS FOR PREVENTING FIRING SYSTEM ACTUATION UNLESS AN UNSPENT STAPLE CARTRIDGE IS PRESENT, now U.S. Pat. No. 10,639,034, each disclose various firing member lockout arrangements. Each of those references is hereby incorporated by reference in its entirety herein. 
     Referring to  FIGS.  60 A- 60 I , there is shown a surgical end effector  9010  that comprises a portion of a surgical tool assembly  9000  that comprises a first jaw  9020  and a second jaw  9120 . In the illustrated arrangement, for example, the first jaw  9020  comprises an elongate channel  9022  that is configured to removably and operably support a surgical staple cartridge  9600  therein. The elongate channel  9022  is attached to an elongate shaft assembly  9300  of the surgical tool assembly. In the arrangement depicted in  FIGS.  60 C and  60 D , for example, the elongate channel  9022  is pivotally coupled to a spine assembly  9310  of the elongate shaft assembly  9300  for selective articulation relative thereto. See  FIGS.  60 D,  60 E,  60 H and  60 I . The elongate shaft assembly  9300  may define a shaft axis SA. The second jaw  9120  comprises an anvil  9122  that is movably supported on the elongate channel  9022  and which is movable between open and closed positions by the closure system  9400 . The anvil  9122  includes an anvil body  9124  and an anvil mounting portion  9126  that is pivotally supported for pivotal travel relative to the proximal end  9024  of the elongate channel  9022 . The closure system  9400  may include, for example, an axially movable distal closure tube segment  9410  that is configured to cammingly engage a cam surface  9128  on the anvil mounting portion  9126  when the distal closure tube segment  9410  is axially advanced in the distal direction DD. The distal closure tube segment  9410  may also be configured to apply opening motions to the anvil mounting portion  9126  when the distal closure tube segment  9410  is moved in the proximal direction PD. See  FIGS.  60 C and  60 D . 
     The surgical tool assembly  9000  further includes a firing system  9500  that, in the illustrated arrangement, comprises a firing member assembly  9510  that is configured to receive firing motions from a firing control system supported in a housing of a handheld control system or a robotic control system, for example. In the illustrated embodiment, one form of firing member assembly  9510  comprises a first firing member element  9520  that consists of a firing member body  9522  that supports a tissue cutting surface or blade  9524  thereon. The firing member body  9522  is coupled to a firing bar or knife bar  9530  that operably interfaces with corresponding portions of the firing system  9500  to receive the firing motions from the firing control system. The firing member body  9522  may include second jaw or anvil engagement features  9526  that may comprise laterally extending tab features configured to be received within corresponding second jaw passages or slots  9125  in the anvil body  9124 . In addition, the firing member body  9522  may further include first jaw or channel engagement features or a foot  9528  that is configured to be received in corresponding first jaw passages or slots or openings  9023  in the elongate channel  9022 . 
     The staple cartridge  9600  comprises a cartridge body  9602 . See  FIGS.  60 H and  60 I . The cartridge body  9602  includes a proximal end  9604 , a distal end (not shown), and a deck  9606  extending between the proximal end and the distal end. In use, the staple cartridge  9600  is positioned on a first side of the tissue to be stapled and the anvil  9122  is positioned on a second side of the tissue. The anvil  9122  is moved toward the staple cartridge  9600  to compress and clamp the tissue against the deck  9606 . Thereafter, staples or fasteners removably stored in the cartridge body  9602  can be deployed into the tissue. The cartridge body  9602  includes staple or fastener cavities (not shown) defined therein wherein staples or fasteners (not shown) are removably stored in the staple cavities. The staple cavities may be arranged in longitudinal rows. In one arrangement, for example, 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. The longitudinal slot is configured to axially receive the first firing member element  9520  therethrough. Other arrangements of staple/fastener cavities and staples or fasteners may be possible. 
     The staples or fasteners are supported by staple drivers (not shown) that are movably supported in the cartridge body  9602 . The drivers are movable between a first, or unfired position, and a second, or fired, position to eject the staples or fasteners from the cavities. The drivers are retained in the cartridge body  9602  by a retainer (not shown) which extends around the bottom of the cartridge body  9602  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  9610 . The sled  9610  is movable between a proximal, or “unfired” position adjacent the proximal end  9604  and a distal or “fired” position adjacent the distal end (after firing). As can be seen in  FIG.  60 G , the sled  9610  comprises a plurality of ramped or cam surfaces  9620  that are configured to slide under the drivers and lift the drivers, and the staples or fasteners supported thereon, toward the anvil. An “unfired”, “unspent”, “fresh” or “new” staple cartridge  9600  means herein that the staple cartridge  9600  has all of its staples or fasteners in their “ready-to-be-fired positions”. When in that position, the sled assembly  9610  is located in its starting or “unfired” position. The new staple cartridge  9600  is seated within the elongate channel  9022  and may be retained therein by snap features on the cartridge body  9602  that are configured to retainingly engage corresponding portions of the elongate channel  9022 .  FIGS.  60 G and  60 H  illustrate a portion of the surgical end effector  9010  with a new or unfired surgical staple cartridge  9600  seated therein. As can be seen in  FIGS.  60 G and  60 H , the sled  9610  is in the unfired position. To prevent the firing system  9500  from being activated and, more precisely, to prevent the first firing member element  9520  from being distally driven through the surgical end effector  9010  unless an unfired or new surgical staple cartridge  9600  has been properly seated within the elongate channel  9022 , the illustrated surgical tool assembly  9000  employs a firing member lockout system generally designated as  9700 . 
     Referring now to  FIGS.  60 E and  60 F , in one form, the firing member lockout system  9700  comprises a second firing member element or tippable element  9710  that comprises a sled engaging portion  9720 . In the illustrated arrangement, the second firing member element  9710  is pivotally coupled to the firing member body  9522  by an attachment joint  9713  in the form of, for example, a pivot member or members  9714  that are pivotally received in corresponding pivot holes  9523  provided in the firing member body  9522  for pivotal travel relative thereto about a pivot axis PA that is transverse to the shaft axis SA. Such arrangement facilitates pivotal travel of the second firing member element  9710  relative to the firing member body  9522  between a locked position ( FIG.  60 E ) and an unlocked position ( FIG.  60 F ). In the illustrated example, the firing member body  9522  comprises a distal surface  9525  that is approximately perpendicular to the channel engagement features  9528  and a lockout surface  9527  that is angled relative to the distal surface  9525 . In addition, one or more support ramps  9529  are formed on the firing member body  9522  that serve to define corresponding landing surfaces  9531  for receiving the second firing member element  9710  when in the locked configuration. See  FIG.  60 E . 
     As can be seen in  FIG.  60 F , when the second firing member element  9710  is in the unlocked position, a space, generally indicated as  9724 , is provided between a proximal surface  9722  of the second firing member element  9710  and the distal surface  9525  of the firing member body  9522 . Thus, when in the unlocked position, the proximal surface  9722  of the second firing member element  9710  is not in contact with the distal surface  9525  of the firing member body  9522 . Referring now to  FIGS.  60 A- 60 D , the second firing member element  9710  further comprises at least one lockout-engaging portion  9730  that includes an angled lock end  9732  that is configured to engage a corresponding lock-out notch  9026  that is formed in the elongate channel  9022  when the second firing member element  9710  is in the locked position. In one embodiment, for example, the second firing member element  9710  includes two lockout-engaging portions  9730 . As can also be seen in  FIGS.  60 A- 60 D , a lockout spring or biasing member  9740  is mounted in the proximal end  9024  of the elongate channel  9022  and includes two spring arms  9742  that each correspond to a lockout-engaging portion  9730 . The spring arms  9742  serve to bias the second firing member element  9710  into the locked position as shown in  FIGS.  60 B- 60 D . 
     Turning now to  FIGS.  60 G- 60 I , the sled  9610  comprises an unlocking portion  9630  that is configured to engage the sled engaging portion  9720  on the second firing member element  9710  when the sled  9610  is in the unfired position. Such arrangement serves to pivot the second firing member element  9710  into the unlocked position. When in the unlocked position, the angled lock end  9732  of each lockout-engaging portion  9730  is pivoted out of the corresponding lock-out notch  9026  in the elongate channel  9022  so that the firing member assembly  9510  may be fired or distally advanced through the staple cartridge. If the staple cartridge that has been loaded into the elongate channel  9022  was previously fired or even partially fired, the sled  9610  will not be in the unfired position so as to pivot the second firing member element  9710  into the unlocked position. In such instance therefor, the clinician will be unable to distally advance or fire the firing member assembly  9510 . When in the unlocked position, actuation of the firing system  9500  will result in the distal travel of the firing member assembly  9510 . As indicated above, when the firing member assembly  9510  is driven distally, the second firing member element  9710  is in contact with the firing member body  9522  through the pivot members  9714 . However, when the second firing member element  9710  is pivoted into the locked position ( FIG.  60 E ), a portion of the proximal surface  9722  is in abutting contact with the angled lockout surface  9527  on the firing member body  9522 . In addition, as can be most particularly seen in  FIGS.  60 E and  60 F , the pivot hole  9523  in the firing member body  9522  is sized relative to the corresponding pivot member  9714  to provide clearance C therebetween so that the load is transferred through the second firing member element directly to the firing member body  9522  and not through the pivot members  9714 . As can be seen in  FIG.  60 E , the angled lockout surface  9527  facilitates pivotal travel of the sled engaging portion  9720  into the locked position. When the second firing member element  9720  is in the locked position, should the clinician inadvertently apply a firing motion FM to the firing member assembly  9510  in the distal direction DD, the engagement between the second firing member element  9720  and the lock-out notch  9026  in the elongate channel  9022  will prevent the distal advancement of the firing member assembly  9510  and cause a resultant unlocking load force UL to be applied to the second firing member element  9720 . This unlocking load force UL will be applied to the angled lockout surface  9527  on the firing member body  9522  and will not be applied to the pivot members  9714 . Such arrangement avoids loading or stressing the pivot members  9714  should the clinician inadvertently attempt to advance the firing member assembly  9510  when in the locked position. Thus, this configuration may prevent the pivot members  9714  from shearing off during such attempted advancement of the firing member assembly  9510 . 
     Thus, the foregoing firing member assembly  9510  and firing member lockout assembly  9700  may provide several advantages. For example, as was discussed above, the distal surface  9525  on the firing member body  9522  carries the load during firing and avoids transferring such load to the pivot members that attach the second firing member element  9710  to the first firing member element  9520 . When in the lockout state or locked position, the load is carried by the angled lock ends  9732  on the lockout engaging portions  9730 . Such arrangement also avoids the need for the firing member assembly  9510  or more precisely the first firing member element  9520  from moving vertically which may inadvertently lead to misalignment with the anvil and elongate channel when moved into an unlocked state for firing. Moreover, because the first firing member element  9520  does not move vertically, the anvil engagement features as well as the channel engagement features may be advantageously shaped and designed to obtain desirable engagement with the anvil and channel during firing. The design and shape of the firing member body may also afford a large surface area for attachment to the knife bar by, for example, welding. For example, the distal end of the knife bar may be attached to the firing member body by a butt weld and a laser weld from both sides to interconnect the laminates forming the knife bar at the distal end. Such weld configuration may be more longitudinally compact than prior weld configurations and can lead to superior joint length. Other advantages may also be enjoyed from the foregoing firing member and lockout system arrangements. 
     An end effector  10500  of a surgical instrument  10000  is illustrated in  FIGS.  79 - 79 B . The end effector  10500  comprises a cartridge jaw  10600  ( FIG.  81   ) including a staple cartridge  10700  and, in addition, an anvil  10800  configured to deform staples ejected from the staple cartridge  10700 . In use, the anvil  10800  is rotatable between an open, unclamped position and a closed, clamped position; however, the cartridge jaw  10600  can be rotatable toward the anvil  10800  in other embodiments. The surgical instrument  10000  further comprises a shaft  10100  wherein the end effector  10500  is rotatably connected to the shaft  10100  about an articulation joint  10200 . In use, the end effector  10500  is rotatable about the articulation joint  10200  between a fully-articulated right position ( FIG.  79 A ), indicated by angle θ R , and a fully-articulated left position ( FIG.  79 B ), indicated by angle θ L —and/or any suitable position there between. As discussed in greater detail below, the angles θ R  and θ L  are limited by the design of the articulation drive system of the surgical instrument  10000 . In at least one instance the angles θ R  and θ L  are limited to approximately 45 degrees with respect to the unarticulated position of the end effector  10500  ( FIG.  79   ). 
     Referring to  FIG.  81   , the shaft  10100  of the surgical instrument  10000  comprises an outer closure tube including an outer housing  10110  which is movable distally to engage the anvil  10800  and move the anvil  10800  toward the staple cartridge  10700 . The shaft  10100  further comprises a distal housing portion  10130  rotatably connected to the outer housing  10110  by two connector plates  10120  positioned on opposite sides of the articulation joint  10200 . Each connector plate  10120  is connected to the outer housing  10110  at a pivot  10115  and, similarly, to the distal housing portion  10130  at a pivot  10125 . The connector plates  10120  permit the closure tube to slide relative to the articulation joint  10200  when the end effector  10500  is in an articulated position and, as a result, the anvil  10800  can be opened and closed while the end effector  10500  is in an articulated position. Further to the above, the distal housing  10130  comprises an opening defined therein configured to receive a tab extending from the proximal end of the anvil  10800 —a sidewall of which is configured to engage the tab and transfer a proximal, or opening motion, of the closure tube to the anvil  10800 . 
     An end effector  11500  of a surgical instrument  11000  is illustrated in  FIGS.  80 - 80 B . The end effector  11500  comprises a cartridge jaw  11600  ( FIG.  82   ) including a staple cartridge  11700  and, in addition, an anvil  11800  configured to deform staples ejected from the staple cartridge  11700 . In use, the anvil  11800  is rotatable between an open, unclamped position and a closed, clamped position; however, embodiments are envisioned in which the cartridge jaw  11600  is movable relative to the anvil  11800 . The surgical instrument  11000  further comprises a shaft  11100  wherein the end effector  11500  is rotatably connected to the shaft  11100  about an articulation joint  11200 . In use, the end effector  11500  is rotatable about the articulation joint  11200  between a fully-articulated right position ( FIG.  80 A ), indicated by angle α R , and a fully-articulated left position ( FIG.  80 B ), indicated by angle α L —and/or any suitable position there between. Although the angles α R  and α L  are ultimately limited by the design of the articulation drive system of the surgical instrument  11000 , the angles α R  and α L  are larger. In at least one instance the angles α R  and α L  are approximately 60 degrees with respect to the unarticulated position of the end effector  11500  ( FIG.  80   ), for example. 
     Referring to  FIG.  82   , the shaft  11100  of the surgical instrument  11000  comprises an outer closure tube including an outer housing  11110  which is movable distally to engage the anvil  11800  and move the anvil  11800  toward the staple cartridge  11700 . The shaft  11100  further comprises a distal housing  11130  rotatably connected to the outer housing  11110  by two connector plates  11120  positioned on opposite sides of the articulation joint  11200 . Each connector plate  11120  is connected to the outer housing  11110  at a pivot  11115  and, similarly, to the distal housing  11130  at a pivot  11125 . Similar to the above, the connector plates  11120  permit the closure tube to slide relative to the articulation joint  11200  when the end effector  11500  is in an articulated position wherein, as a result, the anvil  11800  can be opened and closed while the end effector  11500  is in an articulated position. Further to the above, the distal housing  11130  comprises an opening defined therein configured to receive a tab extending from the proximal end of the anvil  11800 —a sidewall of which is configured to engage the tab and transfer a proximal, or opening, motion of the closure tube to the anvil  11800 . 
     Referring again to  FIG.  81   , the surgical instrument  10000  further comprises an articulation drive system  10300  including an articulation drive actuator  10310  extending through an interior aperture  10105  defined within the closure tube  10110  of the shaft  10100 . The articulation drive actuator  10310  comprises a distal end operably engaged with the cartridge jaw  10600  of the end effector  10500 . More specifically, the distal end of the articulation drive actuator  10310  comprises an opening, or slot,  10320  defined therein and the cartridge jaw  10600  comprises a pin  10620  extending into the slot  10320 . When the articulation drive actuator  10310  is pushed distally, the end effector  10500  is driven to the right ( FIG.  79 A ) about a fixed axis defined by a pivot  10210  which rotatably connects the cartridge jaw  10600  to a frame of the shaft  10100 . Correspondingly, the end effector  10500  is rotated to the left ( FIG.  79 B ) about the pivot  10210  when the articulation drive actuator  10310  is pulled proximally. 
     Referring again to  FIG.  82   , the surgical instrument  11000  further comprises an articulation drive system  11300  including an articulation drive actuator  11310  extending through an interior aperture  11105  defined within the closure tube  11110 . The articulation drive system  11300  further comprises an articulation link  11320  rotatably coupled to a distal end of the articulation drive actuator  11310  about a pin  11315 . Similarly, the articulation link  11320  is rotatably coupled to the cartridge jaw  11600  about a drive pin  11620  which extends through an aperture defined in the articulation link  11320 . When the articulation drive actuator  11310  is pushed distally, the end effector  11500  is driven to the right ( FIG.  80 A ) about a fixed axis defined by a pivot  11210  which rotatably connects the cartridge jaw  11600  to a frame of the shaft  11100 . Correspondingly, the end effector  11500  is rotated to the left ( FIG.  80 B ) about the pivot  11210  when the articulation drive actuator  11310  is pulled proximally. 
     Further to the above, the articulation link  11320  of the articulation system  11300  allows the end effector  11500  to be articulated through a larger range of articulation angles than the end effector  10500  for a given, or equal, stroke length of the articulation actuators  10310  and  11310 . A side-by-side comparison of the end effectors  10500  and  11500  is provided in  FIGS.  83  and  84    illustrating the end effectors  10500  and  11500  in their fully right-articulated configurations—and also illustrating that the end effector  11500  can be articulated further to the right than the end effector  10500 . A similar comparison can be made showing the end effectors  10500  and  11500  in their fully left-articulated configurations. Moreover,  FIG.  85    depicts the full articulation range of the end effector  10500  while  FIG.  86    depicts the full articulation range of the end effector  11500 . 
     Referring again to  FIG.  85   , the articulation actuator  10310  of the surgical instrument  10000  is advanced a distal stroke length (DSL) with respect to its unarticulated position to fully articulate the end effector  10500  to the right. Correspondingly, the articulation actuator  10310  is retracted a proximal stroke length (PSL) with respect to its unarticulated position to fully articulate the end effector  10500  to the left. The distal stroke length (DSL) and the proximal stroke length (PSL) of the articulation actuator  10310  are equal, or at least substantially equal. Referring now to  FIG.  86   , the articulation actuator  11310  is advanced a distal stroke length (DSL) with respect to its unarticulated position to fully articulate the end effector  11500  to the right. Correspondingly, the articulation actuator  11310  is retracted a proximal stroke length (PSL) with respect to its unarticulated position to fully articulate the end effector  11500  to the left. The distal stroke length (DSL) and the proximal stroke length (PSL) of the articulation actuator  11310  are not equal—instead, the distal stroke length (DSL) is shorter than the proximal stroke length (PSL). In other embodiments, the proximal stroke length (DSL) is shorter than the distal stroke length (PSL). In any event, referring now to  FIGS.  94 - 94 B , the combination of the proximal stroke length (PSL) and the distal stroke length (DSL) equals the entire stroke length (SL). 
     Further to the above, the articulation actuator  10310  is configured to apply a torque to the first jaw  10600  of the end effector  10500  via the pin  10620  to rotate the end effector  10500  about the articulation joint  10200 . Referring again to  FIG.  85   , a lateral torque arm defined between the pivot joint  10210  of the articulation joint  10200  and the pin  10620  has a length TA C1  when the end effector  10500  is in its unarticulated position. The length TA C1  is measured in an orthogonal direction with respect to a longitudinal axis  10190  extending through the articulation pivot joint  10210 . Similarly, the lateral torque arm defined between the pivot joint  10210  and the pin  10620  has a length TA R1  when the end effector  10500  is fully articulated to the right and, similarly, a length TA L1  when the end effector  10500  is fully articulated to the left—both lengths of which are measured orthogonally with respect to the longitudinal axis  10190 . Notably, the lengths TA R1  and TA L1 , and the torque arms which they define, are equal, or at least substantially equal. Moreover, the lengths TA R1  and TA L1  are less than the unarticulated lateral torque arm length TA C1 . Thus, the largest torque arm, or mechanical advantage, of the articulation system  10300  exists when the end effector  10500  is in its unarticulated position. 
     In at least one instance, the arm length TA C1  is approximately 0.180″, the arm length TA R1  is approximately 0.130″, and the arm length TA L1  is approximately 0.130″, for example. 
     Further to the above, the articulation actuator  11310  of the surgical instrument  11000  is configured to apply a torque to the first jaw  11600  of the end effector  11500  via the pin  11620  to rotate the end effector  11500  about the articulation joint  11200 . Referring to  FIGS.  86 ,  91 , and  93   , a lateral torque arm (LTA) defined between the pivot joint  11210  of the articulation joint  11200  and the pin  11620  is defined by a length TA C2  when the end effector  11500  is in its unarticulated position. The length TA C2  is measured in an orthogonal direction with respect to a longitudinal axis  11190  extending through the articulation pivot joint  11210 . Notably, the longitudinal axis  11190  is offset and parallel with respect to the centerline of the shaft  11100 , as discussed in greater detail below in connection with  FIG.  88   . Similar to the above, the lateral torque arm defined between the pivot joint  11210  and the pin  11620  is defined by a length TA R2  when the end effector  11500  is fully articulated to the right ( FIG.  93 A ) and, similarly, a length TA L2  when the end effector  11500  is fully articulated to the left ( FIG.  93 B )—both lengths of which are measured orthogonally with respect to the longitudinal axis  11190 . Notably, the length TA R2  is larger than the unarticulated lateral torque arm length TA C1  and the length TA L2  is shorter than the unarticulated lateral torque arm length TA C1 . Moreover, the lengths TA R2  and TA L2 , and the torque arms which they define, are not equal. Instead, the right-articulated torque arm length TA R2  is considerably larger than the left-articulated torque arm length TA L2 . In fact, the right-articulated torque arm length TA R2  and the left-articulated torque arm length TA L2  extend in different directions. Such an arrangement provides for a larger pushing torque arm as compared to a smaller pulling torque arm. In various instances, as a result, the retraction pulling force applied by the articulation actuator  11310  to articulate the end effector  11500  to the left ( FIG.  93 B ) may be, or may need to be, larger than the distal pushing force to articulate the end effector  11500  to the right ( FIGS.  92  and  93 A ). Advantageously, the articulation actuator  11310  can accommodate such a larger pulling force as the articulation actuator  11310  is not subject to buckling failure when being pulled. 
     In at least one instance, the arm length TA C2  is approximately 0.149″, the arm length TA R2  is approximately 0.154″, and the arm length TA L2  is approximately 0.015″, for example. 
     Further to the above, the surgical instrument  11000  is configured and arranged to provide a large torque to the end effector  11500  while, at the same time, providing a large articulation range, or sweep, in response to a short articulation stroke. To wit, several design ratios for these relationships can be established and used to design the surgical instrument  11000 . For instance, a first ratio comprises the fully-right articulated torque arm length (TA) divided by the full articulation stroke length (SL) of the articulation actuator  11310 . The value of this first ratio is unitless. In at least one instance, the fully-right articulated torque arm length (TA) is 0.154″ and the full articulation stroke length (SL) is 0.275″, resulting in a ratio value of 0.56, for example. Larger ratio values for the first ratio indicate more efficient articulation systems. In various instances, the value for the first ratio is less than 1.0, but can be more than 1.0. In at least one instance, the fully-right articulated torque arm length (TA) is 2.79 mm and the full articulation stroke length (SL) is 11.43 mm, resulting in a ratio value of 0.24, for example. 
     The examples provided above for the first ratio were based on the torque arm length (TA) when the end effector  11500  is in its fully-right articulated position. This particular position of the end effector  11500  is notable because the articulation actuator  11310  is in compression and can undergo buckling when the load transmitted there through is excessive. That said, the first ratio could also be used to analyze any suitable position of the end effector  11500  such as its unarticulated position and its fully-left articulated position, for example. In at least one instance, the unarticulated torque arm length (TA) is 6.17 mm, resulting in a ratio value of 0.54 for a stroke length (SL) of 11.43 mm, for example. Also, in at least one instance, the fully-left articulated torque arm length (TA) is 1.41 mm, resulting in a ratio value of 0.12 for a stroke length (SL) of 11.43 mm, for example. 
     A second ratio includes the arc length in which the drive pin  11620  is swept through when the end effector  11500  is articulated between its fully-right articulated position and its fully-left articulated position, i.e., its arc length sweep (ALS). More specifically, the second ratio comprises the arc length sweep (ALS) of the drive pin  11620  divided by the full articulation stroke length (SL) of the articulation actuator  11310 . The value of this second ratio is unitless. In at least one instance, the arc length sweep (ALS) of the drive pin  11620  is 0.387″ and the full articulation stroke length (SL) is 0.275″, resulting in a ratio value of 1.41, for example. In at least one instance, the arc length sweep (ALS) is 0.444″ and the full articulation stroke length (SL) is 0.306″, resulting in a ratio value of 1.45, for example. In at least one instance, the arc length sweep (ALS) is 12.94 mm and the full articulation stroke length (SL) is 11.43 mm, resulting in a ratio value of 1.13, for example. Larger ratio values for the second ratio indicate more efficient articulation systems. In various instances, the value for the second ratio is more than 1.0, such as between 1.0 and 3.0, for example. In at least one instance, the second ratio value is approximately 2.0, for example. In certain instances, the value for the second ratio is about 1.1, but between 0.9 and 1.3, for example. 
     A third ratio comprises the sum of the fully-right articulated torque arm length (TA) and the arc length sweep (ALS) of the drive pin  11620  divided by the full articulation stroke length (SL). The value of this third ratio is unitless. In at least one instance, the fully-right articulated torque arm length (TA) is 0.154″, the arc length sweep (ALS) of the drive pin  11620  is 0.387″, and the full articulation stroke length (SL) is 0.275″, resulting in a ratio value of 1.97, for example. In at least one instance, the fully-right articulated torque arm length (TA) is 2.79 mm, the arc length sweep (ALS) of the drive pin  11620  is 12.94 mm, and the full articulation stroke length (SL) is 11.43 mm, resulting in a ratio value of 1.38, for example. Larger ratio values for the third ratio indicate more efficient articulation systems. In various instances, the value for the third ratio is more than 1.0, such as between 1.0 and 3.0, for example. In at least one instance, the third ratio value is approximately 2.0 or more than 2.0, for example. 
     Similar to the above, the third ratio could be used to evaluate the articulation system when the end effector  11500  is in any suitable position, such as its unarticulated and fully-left articulated positions, for example. 
     A fourth ratio comprises the product of the fully-right articulated torque arm length (TA) and the arc length sweep (ALS) of the drive pin  11620  divided by the full articulation stroke length (SL). The value of this fourth ratio is not unitless and is, instead, measured in distance. In at least one instance, the fully-right articulated torque arm length (TA) is 0.154″, the arc length sweep (ALS) of the drive pin  11620  is 0.387″, and the full articulation stroke length (SL) is 0.275″, resulting in a ratio value of 0.217″, for example. This value can be made unitless by dividing it by the stroke length (SL) once again resulting in a value of 0.79. In at least one instance, the fully-right articulated torque arm length (TA) is 2.79 mm, the arc length sweep (ALS) of the drive pin  11620  is 12.94 mm, and the full articulation stroke length (SL) is 11.43 mm, resulting in a ratio value of 3.15 mm, for example. In certain instances, the value for the fourth ratio is about 3.1 mm, but between 0.9 mm and 5.4 mm, for example. Similar to the above, this value can be made unitless by dividing it by the stroke length (SL) once again resulting in a value of 0.28. Larger ratio values for the fourth ratio indicate more efficient articulation systems. 
     Similar to the above, the fourth ratio could be used to evaluate the articulation system when the end effector  11500  is in any suitable position, such as its unarticulated and fully-left articulated positions, for example. 
     As discussed above, the end effector  11500  is rotatably mounted to the shaft  11100  about a fixed pivot  11210  of the articulation joint  11200 . Referring now to  FIGS.  87  and  88   , the shaft  11100  comprises distal mounting tabs  11220  which extend from and are fixedly mounted to the frame, or spine, of the shaft  11100 . A first distal mounting tab  11220  is mounted to the first jaw  11600 , which comprises a lower frame portion, and a second distal mounting tab  11220  is mounted to an upper frame portion  11230 . The interconnection between the mounting tabs  11220  and the first jaw  11600  and upper frame portion  11230  defines the fixed pivot  11210 . As also discussed above, the fixed axis pivot  11210  is laterally offset with respect to a central longitudinal axis LA of the shaft  11100  by an offset distance OD. In at least one instance, the fixed axis pivot  11210  is laterally offset by approximately 0.036″, for example. Moreover, referring to  FIGS.  91 - 93 B , the pin  11620  is longitudinally offset with respect to the fixed pivot  11210  which creates a longitudinal, or axial, torque arm (ATA). 
     As discussed above, the closure tube of the shaft  11100  is movable distally to engage the anvil jaw  11800  of the end effector  11500  and move the anvil jaw  11800  toward a staple cartridge  11700  positioned in the cartridge jaw  11600 . Stated another way, the closure tube is configured to move the anvil  11800  from an open position ( FIGS.  89 - 89 B ) to a closed position ( FIGS.  90 - 90 B ) to clamp the tissue of a patient against the staple cartridge  11700 . In such instances, the closure tube, comprising the housing  11110 , the connector plates  11120 , and the distal housing  11130 , are slid distally with respect to the articulation joint  11200  during a closure stroke. When the end effector  11500  is in an open, unarticulated configuration, referring now to  FIG.  89   , the connector plates  11120  extend in a direction which is slightly transverse to the central longitudinal axis LA of the shaft  11100 . More specifically, an axis CA extending between the joints  11115  and  11125  is slightly transverse with respect to the central longitudinal axis LA of the shaft  11100  when the end effector  11500  is in an open, unarticulated configuration. When the end effector  11500  is articulated relative to the right ( FIG.  89 A ) or the right ( FIG.  89 B ), the orientation of the axis CA relative to the central longitudinal axis LA can change. 
     In various instances, further to the above, the orientation of the axis CA will change relative to a longitudinal axis extending between the proximal end and the distal end of the end effector  11500 . In at least one instance, the axis CA is transverse to such a longitudinal end effector axis except in one configuration in which the axis CA will be parallel to the longitudinal end effector axis. 
     Further to the above, the orientation of an axis AA defined between the articulation pivot  11210  and the distal pivot  11125  of the connector plates  11120  changes as the end effector  11500  is articulated. Referring to  FIG.  89   , the axis AA extends at an angle β with respect to the axis CA when the end effector  11500  is in an open, unarticulated configuration. When the end effector  11500  is articulated into an open, right configuration ( FIG.  89 A ), the angle β decreases. When the end effector  11500  is articulated into an open, left configuration ( FIG.  89 B ), the angle β increases. At no point, however, is the axis AA collinear with or parallel to the axis CA when the open end effector  11500  is articulated. Instead, the axis AA is transverse to the axis CA when the end effector  11500  is articulated in an open configuration. 
     Referring to  FIG.  90   , the axis AA extends at an angle γ with respect to the axis CA when the end effector  11500  is in a closed, unarticulated configuration. When the end effector  11500  is articulated into a closed, right configuration ( FIG.  90 A ), the angle γ increases. When the end effector  11500  is articulated into a closed, left configuration ( FIG.  90 B ), the angle δ also increases. At no point, however, is the axis AA collinear with the axis CA when the end effector  11500  is articulated in a closed configuration, and/or any other configuration between an open configuration and a closed configuration. Instead, the axis AA is transverse to the axis CA when the end effector  11500  is articulated in a closed configuration and/or any other configuration between an open configuration and a closed configuration. 
     Referring again to  FIGS.  83  and  84   , the design of the surgical instrument  11000  can shorten the end effector  11500  as compared to the end effector  10500 . Also, the distance between the articulation joint  10200  and the proximal end of the staple line that is applied to the tissue of a patient by the end effector  10500  is a distance L 1 —while the distance between the articulation joint  11200  and the proximal end of the staple line that is applied by the end effector  11500  is a distance L 2 , which is shorter than the distance L 1 . 
     Turning now to  FIGS.  103 - 108   , the surgical instrument  11000  further comprises an articulation lock  11400  configured to selectively lock the articulation drive system  11300  and the end effector  11500  in position. The articulation lock  11400  comprises a distal end  11402  mounted to a frame  11180  of the shaft  11100 . More particularly, the shaft frame  11180  comprises pins, or projections,  11182  closely received and/or pressed within apertures defined in the distal end  11402 . The articulation lock  11400  further comprises a proximal end  11404  configured to move relative to the distal end  11402 . In at least one respect, the articulation lock  11400  comprises a cantilever beam where the distal end  11402  comprises a fixed end and the proximal end  11404  comprises a free end. The proximal end  11404  is positioned in a cavity  11184  defined in the shaft frame  11180  and is configured to move laterally toward and away from the articulation drive actuator  11310 , as described in greater detail below. 
     Further to the above, the proximal end  11404  of the articulation lock  11400  comprises one or more teeth  11406  defined thereon which are configured to engage the articulation drive actuator  11310 . As illustrated in  FIG.  103   , the teeth  11406  are arranged in a longitudinal array; however, any suitable arrangement may be used. The articulation drive actuator  11310  comprises a longitudinal array of teeth  11316  defined thereon which are configured to be engaged by the articulation lock teeth  11406 . Referring to  FIG.  104   , the shaft frame  11180  further comprises a longitudinal array of teeth  11186  defined therein which are also configured to be engaged by the articulation lock teeth  11406 . When the articulation lock  11400  is in a fully-locked state, as described in greater detail below, the articulation lock teeth  11406  are engaged with the drive actuator teeth  11316  and the shaft frame teeth  11186  such that the articulation lock  11400  locks the articulation drive actuator  11310  to the shaft frame  11180  and prevents, or at least inhibits, relative movement between the articulation drive actuator  11310  and the shaft frame  11180 . 
     Further to the above, the articulation lock  11400  is configurable in three states—a self-locked state, an unlocked state, and a fully-locked state. When the articulation lock  11400  is in a self-locked stated, referring to  FIG.  106   , the teeth  11406  of the articulation lock  11400  are engaged with the drive actuator teeth  11316  and the shaft frame teeth  11186 . In such instances, the articulation lock  11400  can resist some force transmitted through the articulation drive actuator  11310 ; however, proximal and/or distal movement of the articulation drive actuator  11310  can overcome the holding force of the articulation lock  11400  and displace the articulation lock  11400  into its unlocked configuration, as illustrated in  FIG.  107   . In such instances, the articulation lock  11400  can flex or deflect laterally away from the drive actuator  11310 . The articulation lock  11400  comprises a spring member  11403  extending between the distal portion  11402  and the proximal portion  11404  which is configured to resiliently return, or at least bias, the articulation lock toward its self-locked configuration ( FIG.  105   ). As a result, the articulation drive system  11300  can lock and unlock itself as a result of its own motion and articulate the end effector  11500  unless the articulation lock  11400  is placed in its fully-locked position, as discussed below. 
     As discussed further above, the shaft  11100  of the surgical instrument  11000  comprises a closure tube  11110  that is advanced distally during a closure stroke to close the end effector  11500 . Prior to the closure stroke, the articulation lock  11400  is movable between its self-locked and unlocked configurations to permit the end effector  11500  to be articulated by the articulation drive system  11300 . During the closure stroke, however, the closure tube  11110  is configured to engage the articulation lock  11400  and place or hold the articulation lock  11400  in its fully-locked configuration. More specifically, the closure tube  11110  comprises a projection, or tab,  11118  configured to engage a cam surface  11408  defined on the back side of the articulation lock  11400  and prevent the articulation lock teeth  11406  from becoming demeshed from the drive actuator teeth  11316  and the shaft frame teeth  11186 . When the closure tube  11110  is retracted proximally to open the end effector  11500 , the tab  11118  disengages from the articulation lock  11400  and the articulation lock  11400  is free to move between its self-locked and unlocked positions, as discussed above, so that the end effector  11500  can be articulated once again. 
     The surgical instrument  11000  described above is further illustrated in  FIGS.  143 - 145   . The surgical instrument  11000  comprises a shaft  11100  which is configured for use with a trocar having a passageway defined therein. The surgical instrument shaft  11100  comprises different diameters at different points along the length of the surgical instrument shaft  11100 . Among other things, the surgical instrument shaft  11100  comprises a central region  11160  comprising a smaller diameter than any other region of the surgical instrument shaft  11000 . This geometry of the surgical instrument shaft  11100  provides significant advantages over previous designs and solves a long felt problem associated with the use of a trocar. Typically, when a surgical instrument is used in combination with a trocar during a surgical procedure, the surgical procedure is limited by the range of angles the instrument can take as a result of constrictions created by the trocar passageway. The configuration of the surgical instrument shaft  11100  is an improvement over existing shaft configurations because it increases the range of angles that a surgical instrument can take relative to the longitudinal axis of a trocar. As a result, the user of the surgical instrument  11000  can manipulate the surgical instrument  11000  in a variety of angles relative to the longitudinal axis of the trocar due to the smaller diameter of the central region  11160  of the surgical instrument shaft  11100 . 
     Referring to  FIGS.  143  and  144   , the surgical instrument shaft further  11100  comprises a proximal region  11150  and a distal region  11170 . The proximal region  11150  of the surgical instrument shaft  11000  is located adjacent to a nozzle assembly  11140  of the shaft  11100 . The distal region  11170  is located closest to the end effector  11500 . The proximal region  11150  of the surgical instrument shaft comprises a first diameter, and the central region  11160  comprises a second diameter. The distal region  11170  further comprises a third diameter. The first diameter of the proximal region  11150  is different than the second diameter of the central region  11160 . Similarly, the second diameter of the central region  11160  is different than the third diameter of the distal region  11170 . The first diameter of the proximal region  11150  is different than the third diameter of the distal region  11170 ; however, embodiments are envisioned in which the first diameter and the third diameter are the same. 
     Further to the above, the proximal region  11150  defines a central longitudinal axis. The central region  11160  extends along the central longitudinal axis and is centered with respect to the central longitudinal axis. The proximal region  11150  and the central region  11160  each define a circular profile, although they can comprise any suitable configuration. The distal region  11170  is not centered with respect to the central longitudinal axis. Instead, the distal region  11170  is offset laterally with respect to the central longitudinal axis. Moreover, more of the cross-section and/or perimeter of the distal region  11170  is positioned on a first side of the central longitudinal axis than a second side. In at least one instance, the distal region  11170  comprises an enlargement extending to one side of the central longitudinal axis. Additionally, the distal region  11170  does not define a circular profile. 
     Still referring to  FIGS.  143  and  144   , the central region  11160  comprises a second width that is smaller than the first width of the proximal region  11150 . The central region further comprises a second width which is smaller than the third width of the distal region  11170 . The proximal region  11150  further comprises a different width than the width of the distal region  11170 . For example, the width of the proximal region  11150  is smaller than the width of the distal region  11170 , but is still larger than the width of the central region  11160 . Similarly, the width of the proximal region  11150  is larger than the width of the distal region  11170  and the width of the central region  11160 . In other instances, the proximal region  11150  and the distal region  11170  comprise approximately the same width. 
     Referring to  FIGS.  143 - 145   , the surgical instrument shaft  11100  of the surgical instrument  11000  is configured to fit through a 12 mm trocar, for example. In at least one such instance, the central region  11160  of the surgical instrument shaft  11100  comprises a maximum diameter of approximately 9 mm. Such a diameter of the central region  11160  provides for a wider range of angles that the shaft  11100  can take relative to the centerline of the trocar. Also, such an arrangement can reduce the possibility of causing intercostal nerve damage associated with placing the surgical instrument shaft  11100  between the ribs of a patient during certain surgical procedures. The distal region  11170  of the surgical instrument shaft  11100  is configured to fit through a 12 mm trocar, and comprises one or more flat sides  11172  in order to provide for an increased level of access during procedures which require a high level of articulation. Other embodiments are envisioned in which the shaft  11100  is inserted through a 8 mm trocar and/or a 5 mm trocar, for example. 
     The proximal region  11150  comprises a stepped down, or tapered, region near the proximal end of the surgical instrument shaft  11100 , where the surgical instrument shaft  11100  transitions from the proximal region  11150  to the central region  11160 . The central region  11160  further comprises a stepped up, or tapered, region near the distal end of the surgical instrument shaft  11100 , where the surgical instrument shaft  11100  transitions from the central region  11160  to the distal region  11170 . 
     Still referring to  FIGS.  143  and  144   , the proximal region  11150  comprises a first circumference, the central region  11160  comprises a second circumference, and the distal region  11170  comprises a third circumference. The circumference of the proximal region  11150  is different than the circumference of the central region  11160 , owing to the difference in diameters of such portions of the surgical instrument shaft  11100 . Similarly, the circumference of the central region  11160  and the circumference of the distal region  11170  are different. The circumference of the proximal region  11150  and the circumference of the distal region  11170  are the same, but can be different in other embodiments. 
     Referring again to  FIGS.  143  and  144   , the surgical instrument shaft  11100  comprises a single, formed piece of material, although the surgical instrument shaft  11100  can comprise multiple pieces of material that are combined to form a single, cohesive surgical instrument shaft in other instances. The pieces of material can be assembled using any appropriate process. The surgical instrument shaft  11100  is configured to operate with a variety of surgical arrangements not limited to the surgical stapling instruments described above. The surgical instrument shaft  11100  can be used with other surgical instruments having articulatable end effectors. The other surgical instruments can include, for example, ultrasonic surgical devices, clip appliers, and fastener appliers. In addition, the surgical instrument shaft  11100  is configured for use with any surgical instrument wherein use of a trocar passageway is appropriate. 
     Further to the above, the outer tube  11110  of the shaft  11100  comprises a proximal end  11150  and a longitudinal portion  11160  comprising a diameter, or width, which is narrower than the diameter, or width, of the proximal end  11150 . That said, the surgical instrument  11000  is configured and arranged to provide a large torque to the end effector  11500  while, at the same time, the longitudinal portion  11160  comprises a narrow diameter. To wit, at least one design ratio for this relationship can be established and used to design the surgical instrument  11000 . For instance, one ratio comprises the diameter of the longitudinal portion  11160  (D) divided by the fully-right articulated torque arm length (TA). The value of this ratio is unitless. In at least one instance, the diameter of the longitudinal portion  11160  (D) is 0.316″ and the torque arm length (TA) is 0.154″, resulting in a ratio value of 2.06, for example. Smaller values for this ratio indicate more efficient articulation systems. In various instances, the value for this ratio is less than 2.0, such as between 1.0 and 2.0, for example. In at least one instance, the ratio value is between 2.0 and 3.0, for example. In certain instances, the ratio value is smaller than 3.38, for example. 
     Further to the above, the outer tube  11110  of the shaft  11100  comprises a longitudinal portion  11160  and an enlarged distal end  11170  ( FIG.  143   ). Referring again to  FIG.  103   , the entirety of the articulation lock  11400  is positioned in the longitudinal portion  11160  and not the enlarged distal end  11170 . Embodiments are envisioned, however, in which at least a portion of the articulation lock  11400  is positioned in the enlarged distal end  11170 . In at least one such instance, the articulation lock  11400  is mounted to the shaft frame such that the distal end  11402  of the articulation lock  11400  is in the enlarged distal end  11170  of the outer tube  11110 . In certain instances, the articulation lock  11400  is re-arranged such that the movable end of the articulation lock  11400  is positioned in the enlarged distal end  11170  of the outer tube  11110 . In various instances, the entirety of the articulation lock  11400  is positioned in the enlarged distal end  11170 . 
     Turning now to  FIG.  109   , a surgical instrument  14000  comprises a shaft  14100 , an end effector  11500 , and, in addition, an articulation drive system including an articulation drive actuator  14310  configured to articulate the end effector  11500 . The shaft  14100  comprises an articulation lock system configured to selectively lock the articulation drive actuator  14310  and the end effector  14500  in position. The articulation lock system comprises an articulation lock  14400  including proximal end and distal ends mounted to a frame  14180  of the shaft  14100 . In at least one respect, the articulation lock  14400  comprises a beam fixedly and/or simply-supported at both ends. The articulation lock  14400  further comprises an intermediate portion  14404  positioned in a cavity  14184  defined in the shaft frame  14180  which is configured to move laterally toward and away from an articulation drive actuator  14310  of the articulation drive system  14300 . Similar to the above, the articulation lock  14400  comprises one or more spring portions  14403  configured to permit the articulation lock  14400  to flex toward and away from the articulation drive actuator  14310 . 
     Further to the above, the intermediate portion  14404  of the articulation lock  14400  comprises one or more teeth  14406  defined thereon which are configured to engage the articulation drive actuator  14310 . The teeth  14406  are arranged in a longitudinal array; however, any suitable arrangement may be used. The articulation drive actuator  14310  comprises a longitudinal array of teeth  14316  defined thereon which are configured to be engaged by the articulation lock teeth  14406 . The articulation lock system further comprises a lock plate  14420  slidably positioned in the shaft cavity  14184  which includes a longitudinal array of teeth  14226  defined therein which are also configured to be engaged by the articulation lock teeth  14406 . When the articulation lock  14400  is in a fully-locked state, as described in greater detail below, the articulation lock teeth  14406  are engaged with the drive actuator teeth  14316  and the lock plate teeth  14226  such that the articulation lock  14400  locks the articulation drive actuator  14310  in position and prevents, or at least inhibits, relative movement between the articulation drive actuator  14310  and the shaft frame  14180 . 
     The lock plate  14420  comprises a shoulder  14424  which is positioned under the articulation drive actuator  14310 . The lock plate teeth  14426  are defined on a lateral edge of the shoulder  14424  and are substantially aligned with the teeth  14316  defined in the articulation drive actuator  14310 . In at least one instance, the articulation drive actuator teeth  14316  are aligned along a first teeth axis and the lock plate teeth  14406  are defined along a second teeth axis which is parallel, or at least substantially parallel, to the first teeth axis. In various instances, the drive actuator teeth  14316  are defined in a plane which is parallel to a plane including the lock plate teeth  14406 . Such arrangements permit the articulation lock  14400  to simultaneously engage the lock plate  14420  and the articulation drive actuator  14310 . Although the first teeth axis and the second teeth axis are parallel to a longitudinal axis of the shaft  14100 , embodiments are envisioned in which the first teeth axis and the second teeth axis are skew or transverse with respect to the longitudinal axis of the shaft  14100 . 
     Referring again to  FIG.  109   , the lock plate  14420  is slidable longitudinally within the cavity  14184 ; however, the longitudinal movement of the lock plate  14420  is limited by proximal and distal end walls  14427 . As a result, the lock plate  14420  can float within the shaft cavity  14184  between the end walls  14427 . In various instances, the lock plate teeth  14426  may not be completely aligned with the drive actuator teeth  14316  when the articulation lock  14400  engages the teeth  14426  and  14316 . In such instances, the lock plate  14420  can move longitudinally, to a certain degree, such that the lock plate teeth  14426  are aligned with the drive actuator teeth  14316 . In various instances, the lock plate  14420  can move in response to a locking force applied thereto by the articulation lock  14400 . In at least one instance, the lock plate  14420  can be permitted to move distally one tooth pitch distance and proximally one tooth pitch distance with respect to its centered position, for example, wherein a tooth pitch distance is the distance between the peaks of adjacent lock teeth  14426  of the lock plate  14420 . In other instances, the lock plate  14420  can be permitted to move distally ¼ of a tooth pitch distance and proximally ¼ of a tooth pitch distance with respect to its centered position, for example. In various instances, the lock plate  14420  can be permitted to move proximally and distally more than one toot pitch distance. 
     Further to the above, the articulation lock  14400  is configurable in three states—a self-locked state, an unlocked state, and a fully-locked state. When the articulation lock  14400  is in a self-locked stated, the teeth  14406  of the articulation lock  14400  are engaged with the drive actuator teeth  14316  and the shaft frame teeth  14186 . In such instances, the articulation lock  14400  can resist some force transmitted through the articulation drive actuator  14310 ; however, proximal and/or distal movement of the articulation drive actuator  14310  can overcome the holding force of the articulation lock  14400  and displace the articulation lock  14400  into its unlocked configuration. In such instances, the articulation lock  14400  can flex or deflect laterally away from the drive actuator  14310  so that the end effector  11500  can be articulated. Similar to the above, the spring members  14403  of the articulation lock  14400  can resiliently return, or at least bias, the articulation lock  14400  toward its self-locked configuration. As a result, the articulation drive system can lock and unlock itself as a result of its own motion unless it is placed in its fully-locked position, as discussed below. 
     Similar to the above, the shaft  14100  of the surgical instrument  14000  comprises a closure tube that is advanced distally during a closure stroke to close the end effector  11500 . Prior to the closure stroke, the articulation lock  14400  is movable between its self-locked and unlocked configurations to permit the end effector  11500  to be articulated by the articulation drive system. During the closure stroke, the closure tube is configured to engage the articulation lock  14400  and place, block, and/or hold the articulation lock  14400  in its fully-locked configuration. More specifically, the closure tube comprises a cam  14118  configured to engage a cam surface  14405  defined on the back side of the articulation lock  14400  and prevent the articulation lock teeth  14406  from becoming de-meshed from the drive actuator teeth  14316  and the shaft frame teeth  14186 . The cam  14118  comprises an angled surface  14115  which engages a corresponding angled surface defined on the cam surface  14405 , although any suitable arrangement could be used. When the closure tube is retracted proximally to permit the end effector  11500  to be opened, the tab  14118  disengages from the articulation lock  14400  and the articulation lock  14400  is free to move between its self-locked and unlocked positions, as discussed above, so that the end effector  11500  can be articulated once again. 
     When the articulation lock  14400  is moved into its fully-locked configuration by the closure tube, referring again to  FIG.  109   , the articulation lock  14400  pushes the lock plate  14420  against a lateral sidewall  14183  of the shaft cavity  14184 . In fact, the articulation lock  14400  engages the lock plate  14420  with sufficient force to pin the lock plate  14420  against the sidewall  14183  such that the lock plate  14420  cannot move, or at least substantially move, longitudinally with respect to the shaft frame  14180 . The lock plate  14420  comprises one or more projections  14422  extending therefrom which are configured to dig into, bite, and/or deflect the sidewall  14183  of the shaft cavity  14184  when the lock plate  14420  is pushed against the sidewall  14183  to prevent, or at least reduce the possibility of, the lock plate  14420  from moving longitudinally relative to the shaft frame  14180 . 
     Further to the above, the shaft frame  14180  comprises one or more cavities, or openings, defined therein which are configured to permit and/or facilitate the deflection of the sidewall  14183 . For example, as illustrated in  FIG.  109   , the shaft frame  14180  comprises cavities  14182  defined therein which are aligned, or at least substantially aligned, with the projections  14422 . When the lock plate  14420  is displaced laterally by the closure tube, as discussed above, the sidewall  14183  elastically displaces into the cavities  14182  and the lock plate  14420  is locked in position. In such instances, the engagement between the shaft frame  14180  and the lock plate  14420  prevents the articulation drive actuator  14310  from being moved longitudinally and locks the end effector  11500  in position. When the closure tube is retracted and disengaged from the articulation lock  14400 , the sidewall  14183  can return to its unflexed state and displace the lock plate  14420  laterally. At such point, the lock plate  14420  is unlocked and the end effector  11500  can be articulated, as outlined above. 
     A surgical instrument  15000  is illustrated in  FIGS.  110 - 112    and is similar to the surgical instrument  14000  in many respects, most of which will not be repeated herein for the sake of brevity. Among other things, the surgical instrument  15000  comprises a shaft, an end effector  11500 , and an articulation drive system including an articulation drive actuator  14310 . The surgical instrument  15000  further comprises an articulation locking system including an articulation lock  15400  which is, similar to the above, movable between a self-locking position, an unlocked position, and a fully-locked position. The articulation locking system further comprises a lock plate  15420  which is similar to the lock plate  14420  in many respects. For instance, the lock plate  15420  is movable laterally into engagement with the wall  14183 . Also, for instance, the lock plate  15420  is movable longitudinally to float into a suitable locked position in which an array of teeth  15426  defined on the lock plate  15420  are meshed with the teeth  14406  of the articulation lock  15400 , as depicted in  FIG.  111   . That said, the shaft of the surgical instrument  15000  further comprises a distal spring  15429  positioned intermediate the lock plate  15420  and a distal end wall  15427  defined in the shaft frame and, in addition, a proximal spring  15429  positioned intermediate the lock plate  15420  and a proximal end wall  15427  defined in the shaft frame. The springs  15429  are configured to position the lock plate  15420  in a centered, or balanced, position between the end walls  15427 , which is illustrated in  FIG.  110   . Such a centered position creates a proximal gap (PG) and a distal gap (DG) between the end walls  15427  and the lock plate  15420  which are equal, or at least substantially equal, to one another. That said, the springs  15429  may experience different deflections or loading when the lock plate  15420  seats itself into meshing engagement with the articulation lock  15400 , as illustrated in  FIG.  112   , which may create unequal gaps PG and DG. 
     A surgical instrument  16000  is illustrated in  FIGS.  113 - 115    and is similar to the surgical instruments  14000  and  15000  in many respects, most of which will not be repeated herein for the sake of brevity. Among other things, the surgical instrument  16000  comprises a shaft, an end effector  11500 , and an articulation drive system including an articulation driver  16310 . Referring primarily to  FIG.  113   , the surgical instrument  16000  further comprises an articulation locking system including an articulation lock  16400  which is, similar to the above, configurable in a self-locking configuration, an unlocked configuration, and a fully-locked configuration. The articulation locking system further comprises a lock plate  16420  which is similar to the lock plate  14420  in many respects. For instance, the lock plate  16420  is movable laterally into engagement with the wall  14183 , as illustrated in  FIG.  114   . Also, for instance, the lock plate  16420  is movable longitudinally to float into a suitable locked position in which teeth  16426  of the lock plate  16420  are meshed with the teeth  16406  of the articulation lock  16400 , as depicted in  FIG.  115   . Moreover, the teeth  16406  of the articulation lock  16400 , the teeth  16426  of the lock plate  16420 , and the lock teeth  16316  of the articulation driver  16310  are configured and arranged to provide a plurality of positions, or permutations of positions, in which the articulation lock  16400  can lock the articulation driver  16310  to the lock plate  16420 . For instance, the articulation lock system has reached a fully-locked configuration in a set of positions illustrated in  FIG.  114    and a fully-locked configuration in a different set of positions illustrated in  FIG.  115   . 
     The above-discussed adaptability of the articulation locking system can be achieved via the tooth pitches of the articulation lock teeth  16406 , the articulation driver teeth  16316 , and the lock plate teeth  16426 . For instance, referring primarily to  FIG.  113   , the articulation lock teeth  16406  are set at a first pitch  16407 , the articulation driver teeth  16316  are set at a second pitch  16317 , and the lock plate teeth  16426  are set at a third pitch  16427 . The first pitch is different than the second pitch and the third pitch—the second pitch is different than the first pitch and the third pitch—and the third pitch is different than the first pitch and the second pitch, although embodiments are envisioned in which two of the first pitch, the second pitch, and the third pitch are the same. Referring again to  FIG.  113   , the third pitch  16427  of the lock plate teeth  16426  is larger than the second pitch  16317  of the articulation driver teeth  16316 , and the second pitch  16317  is larger than the first pitch  16407  of the articulation lock teeth  16406 , although any suitable arrangement can be used. 
     A surgical instrument  17000  is illustrated in  FIGS.  116 - 119    and is similar to the surgical instrument  11000  in many respects, most of which will not be repeated herein for the sake of brevity. The surgical instrument  17000  comprises a shaft, an end effector  11500  rotatably connected to the shaft about an articulation joint  11200 , and an articulation drive system configured to articulate the end effector  11500  about the articulation joint  11200 . Similar to the above, the articulation drive system comprises an articulation link  17320  rotatably mounted to the jaw  11600  about a pin  11620  and an articulation driver  17310  rotatably mounted to the articulation link  17320  about a pin  17315 . The surgical instrument  17000  further comprises an articulation lock  17400  movably mounted to a shaft frame of the surgical instrument  17000  which is movable between an unlocked position and a locked position. The articulation lock  17400  comprises a distal end  17402  fixedly mounted to the shaft frame and a proximal end  17404  slidably mounted to the shaft frame. More specifically, the shaft frame comprises a pin extending into an aperture defined in the distal end  17402  of the articulation lock  17400  and a guide projection  17114  extending into an elongate aperture defined in the proximal end  17404 . In certain instances, the shaft frame can comprise two or more pins extending into apertures defined in the distal end  17402  of the articulation lock  17400  to fix the distal end  17402  to the shaft frame and prevent the distal end  17402  from rotating relative to the shaft frame. As a result of the above, at least the proximal end  17404  of the articulation lock  17400  is movable relative to the shaft frame to engage the articulation driver  17310  and lock the articulation system and end effector  11500  in position. 
     Further to the above, the articulation driver  17310  comprises a longitudinal rack of teeth  17316  defined thereon and the articulation lock  17400  comprises a longitudinal rack of teeth  17406  defined thereon. When the articulation lock  17400  is in its unlocked position, as illustrated in  FIGS.  116 - 117   , the teeth  17406  of the articulation lock  17400  are not engaged with the teeth  17316  of the articulation driver  17310 . In such instances, the articulation driver  17310  can move freely relative to the articulation lock  17400  to articulate the end effector  11500 . When the articulation lock  17400  is in a partially-locked position, as illustrated in  FIG.  118   , the articulation lock teeth  17406  are partially engaged with the articulation driver teeth  17316 . In such instances, the proximal and distal movement of the articulation driver  17310  is impeded by the articulation lock  17400 ; however, the articulation driver  17310  can still move relative to the articulation lock  17400  to articulate the end effector  11500 . When the articulation lock  17400  is in a fully-locked position, as illustrated in  FIG.  119   , the articulation lock teeth  17406  are fully engaged with the articulation driver teeth  17316 . In such instances, the proximal and distal movement of the articulation driver  17310 , and the articulation of the end effector  11500 , is prevented by the articulation lock  17400 . 
     Further to the above, the surgical instrument  17000  does not include a biasing member configured to move the articulation lock  17400  toward the articulation driver  17310  other than a closure member, or tube,  17110 . The closure tube  17110  is configured to engage the articulation lock  17400  and move the articulation lock  17400  from its unlocked position ( FIG.  117   ) to its partially-locked ( FIG.  118   ) and fully-locked positions ( FIG.  119   ). Similar to the above, the closure tube  17110  comprises a cam  17118  configured to engage a cam surface defined on the articulation lock  17400 , although other arrangements can be used. The closure tube  17110  is configured to move the articulation lock  17400  between its unlocked position and its partially-locked position when the closure tube  17110  is moved distally through a partial closing stroke (PCS) which at least partially closes the end effector  11500 . In such instances, the end effector  11500  of the surgical instrument  17000  can be used to grasp the tissue of a patient, for example. The closure tube  17110  is configured to move the articulation lock  17400  into its fully-locked position when the closure tube  17110  is moved distally through a full closing stroke (FCS) which completely closes the end effector  11500 . In such instances, the end effector  11500  of the surgical instrument  17000  can be used to fully clamp the tissue of a patient, for example. 
     As discussed above, the locking force applied to the articulation driver  17310  by the articulation lock  17400  increases as the closure tube  17110  is advanced distally. Stated another way, the articulation locking force is a function of the closure tube  17110  stroke. Further to the above, turning now to  FIG.  120   , the locking force between the articulation driver  17310  and the articulation lock  17400  is represented by line  17101 . As illustrated in  FIG.  120   , the articulation lock teeth  17406  become initially engaged with the articulation driver teeth  17316  during the partial closure stroke. In at least one instance, such initial engagement of the teeth  17406  and  17316  occurs after approximately 0.050″ of closure stroke of the closure tube  17110 , although any suitable distance can be used. Notably, such initial engagement of the teeth  17406  and  17316  does not necessarily coincide with the end of the partial closing stroke; rather, it can occur at some point during the partial closure stroke (PCS). It also occurs at some point during the full closure stroke (FCS). Such an initial engagement, however, does not comprise a locking force couple. Instead, a locking force couple between the teeth  17406  and  17316  is only established at some during the full closing stroke (FCS). In at least one instance, the full closing stroke (FCS) has a length of approximately 0.260″, for example. 
     A surgical instrument  18000  is illustrated in  FIGS.  121 - 123    and is similar to the surgical instruments  11000  and  17000  in many respects, most of which will not be repeated herein for the sake of brevity. The surgical instrument  18000  comprises a shaft, an end effector  11500  rotatably connected to the shaft about an articulation joint, and an articulation system configured to articulate the end effector  11500 . The shaft comprises a frame  18180  including first and second longitudinal racks of teeth  18186  which are parallel, or at least substantially parallel, to one another, although the racks of teeth  18186  can extend transversely to one another. The surgical instrument  18000  further comprises an articulation lock  18400  and a closure member including a cam  18118 . The articulation lock  18400  includes a first lock arm  18410  configured to engage the first longitudinal rack of teeth  18186  and a second lock arm  18420  configured to engage the second longitudinal rack of teeth  18186 . Referring primarily to  FIGS.  122  and  123   , the first lock arm  18410  comprises a first cam surface  18415  defined thereon and the second lock arm  18420  comprises a second cam surface  18425  defined thereon which are configured to be contacted by the cam  18118  during a closure stroke of the closure member and displaced or flexed outwardly into a fully-locked engagement with the longitudinal racks of teeth  18186 . Moreover, one or both of the lock arms  18410  and  18420  also engage the articulation system to lock the end effector  11500  in place when the lock arms  18410  and  18420  are displaced outwardly into engagement with the shaft frame  18180 . 
     Once displaced or flexed into their fully-locked states, the lock arms  18410  and  18420  define a longitudinal slot  18430  there between which is configured to permit the cam  18118  to pass thereby during the remainder of the closure stroke, for example. Moreover, in such instances, the cam  18118  wedges the articulation lock  18400  into engagement with the frame  18180  and securely holds the lock arms  18410  and  18420  in their fully-locked positions. 
     In at least one alternative embodiment, further to the above, the first lock arm  18410  of the articulation lock  18400  can be configured to engage the shaft frame  18180  of the surgical instrument  18000  while the second lock arm  18420  of the articulation lock  18400  can be configured to engage the articulation system of the surgical instrument  18000 . 
     A surgical instrument  19000  is illustrated in  FIGS.  124 - 128    and is similar to the surgical instrument  11000  in many respects, most of which will not be repeated herein for the sake of brevity. The surgical instrument  19000  comprises a shaft  19100  including a closure member  19110 , an end effector  11500  rotatably connected to the shaft  19100  about an articulation joint  11200 , and an articulation drive system  19300  including an articulation driver  19310  configured to articulate the end effector  11500  about the articulation joint  11200 . Referring primarily to  FIG.  124   , the surgical instrument  19000  further comprises an articulation lock  19400  configured to selectively engage the articulation drive system  19300  and lock the end effector  11500  in position. The shaft  19100  further comprises a frame  19180  and the articulation lock  19400  is movably mounted to the frame  19180  between an unlocked position ( FIG.  124   ), a partially-locked position ( FIG.  126   ), and a locked position ( FIG.  127   ). As described in greater detail below, the articulation lock  19400  is movable laterally toward the articulation driver  19310  to bring the articulation lock  19400  into close approximation with the articulation driver  19310  ( FIG.  126   ) and, also, transversely into interference with the articulation driver  19310  ( FIG.  127   ). 
     Further to the above, the shaft frame  19180  comprises a proximal guide post  19182  and a distal guide post  19184 . The proximal guide post  19182  extends into a lateral elongate slot defined in a proximal end  19402  of the articulation lock  19400  and, similarly, the distal guide post  19184  extends into a lateral elongate slot defined in a distal end  19404  of the articulation lock  19400 . The lateral elongate slots permit the articulation lock  19400  to move laterally toward and away from the articulation driver  19310 , as outlined above. The lateral elongate slots also define the lateral path of the articulation lock  19400  and prevent, or at least substantially prevent, longitudinal movement of the articulation lock  19400  relative to the shaft frame  19180 . As a result, the elongate slots of the articulation lock  19400  can guide the articulation lock  19400  between an unlocked position ( FIG.  124   ) in which the lock teeth  19406  of the articulation lock  19400  are not engaged with a longitudinal rack of teeth  19316  defined on the articulation driver  19310 , a partially-locked position ( FIG.  126   ) in which the lock teeth  19406  are partially engaged with the teeth  19316 , and a fully-locked position ( FIG.  127   ) in which the lock teeth  19406  are fully engaged with the teeth  19316 . 
     Further to the above, the articulation lock  19400  further comprises a longitudinal cam slot  19408  defined therein and the closure member  19110  comprises a cam pin  19188  positioned in the cam slot  19408 . When the closure member  19110  is in an unactuated, or open, position ( FIG.  124   ), the cam pin  19188  is positioned in a proximal portion  19408   a  of the cam slot  19408 . When the closure member  19110  is moved distally into a partially-actuated, or partially-closed, position, as illustrated in  FIG.  125   , the cam pin  19188  is moved into a central portion  19408   b  of the cam slot  19408 . In such instances, the cam pin  19188  displaces the articulation lock  19400  toward the articulation driver  19310 . In such instances, however, the teeth  19406  of the articulation lock  19400  may not be engaged with the teeth  19316  of the articulation driver  19310  and, as a result, the articulation driver  19310  can still be moved to articulate the end effector  11500  relative to the shaft  19100 . As a result, the end effector  11500  can be articulated when the closure stroke of the closure member  19110  has only been partially completed. 
     When the closure member  19110  is moved further distally, as illustrated in  FIG.  126   , the cam pin  19188  is moved into a distal portion  19408   c  of the cam slot  19408 . In such instances, the cam pin  19188  displaces the articulation lock  19400  into close approximation with the articulation driver  19310  and into partial intermeshment with the teeth  19316  of the articulation driver  19310 . That said, such partial intermeshment between the teeth  19406  and  19316  can only resist a certain amount of force transmitted through the articulation driver  19310  and such resistance can be overcome to move the articulation driver  19310  relative to the articulation lock  19400  and articulate the end effector  11500 . 
     Further to the above, the articulation lock  19400  is not transversely lifted or lowered relative to the shaft frame  19180  during the partial closure stroke of the closure member  19110  ( FIGS.  124 - 126   ). Rather, the articulation lock  19400  is lifted upwardly such that teeth  19406  of the articulation lock  19400  fully engage the teeth  19316  of the articulation driver  19310  and lock the articulation driver  19310  in position during the final or last portion of the closure stroke of the closure member  19110 , as illustrated in  FIG.  127   . The articulation lock  19400  is moved upwardly by a different cam pin extending from the closure member  19110 , i.e., cam pin  19189  which engages the articulation lock  19400  at the end of the closure stroke of the closure member  19110 . Notably, the cam pin  19189  is not engaged with the articulation lock  19400  at the beginning of the closure stroke or during the partial closure stroke of the closure member  19110 . At most, the cam pin  19189  may slidingly touch the bottom of the articulation lock  19400  during the partial closure stroke. That said, referring primarily to  FIG.  128   , the articulation lock  19400  comprises a cut-out, or recess,  19409  defined therein which provides clearance between the cam pin  19189  and the articulation lock  19400  during the partial closure stroke. That said, the cam pin  19189  comes into contact with the articulation lock  19400  when the cam pin  19189  reaches the end of the recess  19409  and, in such instances, drives the articulation lock  19400  transversely upwardly such that the lock teeth  19406  interferingly engage with the teeth  19316  of the articulation driver  19310  and the articulation lock  19400  is placed in its fully-locked position, as illustrated in  FIG.  127   . At such point, the articulation driver  19310  is locked in position and cannot be moved longitudinally to articulate the end effector  11500 . 
     Referring again to  FIG.  128   , the teeth  19316  of the articulation driver  19310  are angled, or tilted, relative to the longitudinal axis of the shaft  19100 . The lock teeth  19406  of the articulation lock  19400  are not angled, or are angled at a different orientation than the teeth  19316 . As a result, the lock teeth  19406  of the articulation lock  19400  can be partially engaged with the teeth  19316  of the articulation driver  19310  when the articulation lock  19400  is in its lowered position ( FIG.  126   ) and fully engaged with the teeth  19316  when the articulation lock  19400  is in its raised position ( FIG.  127   ). 
     In order to unlock the articulation system  19300  of the surgical instrument  19000 , the closure member  19110  must be retracted to disengage the cam pin  19189  from the articulation lock  19400  so that the articulation lock  19400  can return to its lowered position. Once the cam pin  19189  has been disengaged from the articulation lock  19400 , the proximal retraction of the cam pin  19188  can drive the articulation lock  19400  downwardly as the cam pin  19188  is pulled proximally through cam slot  19408 . Moreover, the cam pin  19188  can displace the articulation lock  19400  away from the articulation driver  19310  when it is pulled proximally. In various embodiments, the shaft  19110  can comprise one or more biasing members, such as springs, for example, configured to bias or push the articulation lock  19400  downwardly to quickly reset the articulation lock to an unlocked position. 
     A surgical instrument  20000  is illustrated in  FIGS.  129 - 131    and is similar to the surgical instruments  11000 ,  17000 ,  18000 , and  19000  in many respects, most of which will not be repeated herein for the sake of brevity. The surgical instrument  20000  comprises a shaft including a closure tube  20110 , an end effector  11500  rotatably mounted to the shaft about an articulation joint  11200 , and an articulation system configured to articulation the end effector  11500  relative to the shaft. Similar to the above, the articulation system comprises an articulation link  20320  rotatably pinned to the end effector  11500  and, in addition, an articulation actuator  20310  rotatably pinned to the articulation link  20320 . In use, the articulation actuator  20310  is moved proximally and/or distally to drive the articulation link  20320  and articulate the end effector  11500 . The surgical instrument  20000  further comprises an articulation lock system comprising an articulation lock gear  20400  rotatably mounted to a frame of the shaft about a fixed axis. The articulation lock gear  20400  comprises an annular array of teeth  20406  which is meshingly engaged with a longitudinal array of teeth  20316  defined on the articulation actuator  20310 . As a result, referring generally to  FIG.  129   , the articulation lock gear  20400  will rotate in response to the proximal and/or distal movement of the articulation actuator  20310  until the articulation lock gear  20400  is locked in position by the closure tube  20110 , as illustrated in  FIG.  131   . 
     Further to the above, the articulation lock system further comprises lock arms  20405  extending from the shaft frame into a central aperture defined in the articulation lock gear  20400  and, when the closure tube  20110  is moved distally during a closure stroke to close the end effector  11500 , a cam, or wedge,  20118  of the closure tube  20110  is configured to engage the lock arms  20405  and splay the lock arms  20405  outwardly into engagement with the articulation lock gear  20400 . Once the lock arms  20405  are engaged with the articulation lock gear  20400 , the lock arms  20405  can prevent the rotation of the articulation lock gear  20400  and, also, the longitudinal movement of the articulation actuator  20310 . In such instances, the lock arms  20405  can prevent, or at least substantially prevent, the articulation of the end effector  11500  until the wedge  20118  of the closure tube  20110  is retracted proximally during an opening stroke and the lock arms  20405  resiliently return to their unflexed, or unlocked, configurations. 
     Further to the above, the articulation system of the surgical instrument  20000  can be placed in an unlocked configuration ( FIG.  129   ), a partially-locked configuration ( FIG.  130   ), and a fully-locked configuration ( FIG.  131   ). The articulation system can be placed in its partially-locked configuration ( FIG.  130   ) when the closure tube  20110  is advanced distally through a partial closing stroke (PCS). In such instances, the end effector  11500  is at least partially closed but can still be articulated even though the lock arms  20405  may be partially engaged with the articulation lock gear  20400 . More particularly, the articulation lock gear  20400  can still rotate despite drag created by the partial engagement of the lock arms  20405  against the articulation lock gear  20400 . In at least one instance, the PCS is approximately 0.050″, for example. The articulation system can be placed in its fully-locked configuration ( FIG.  131   ) when the closure tube  20110  is advanced distally through a full closure stroke (FCS). In such instances, the end effector  11500  is completely closed and cannot be articulated until the articulation system is returned to its partially-locked and/or unlocked configurations. 
     A surgical instrument  21000  is illustrated in  FIGS.  132 - 134    and is similar to the surgical instruments  11000 ,  17000 ,  18000 ,  19000 , and  20000  in many respects, most of which will not be repeated herein for the sake of brevity. The surgical instrument  21000  comprises a shaft including a closure member  21110 , an end effector  11500  rotatably mounted to the shaft about an articulation joint  11200 , and an articulation system including an articulation actuator  21130  configured to articulate the end effector  11500  relative to the shaft. The surgical instrument  21000  further comprises an articulation lock system comprising an articulation lock gear  21400  rotatably mounted to a frame of the shaft about a fixed axis. The articulation lock gear  21400  comprises an annular array of teeth  21406  which is meshingly engaged with a longitudinal array of teeth  21316  defined on the articulation actuator  21310 . As a result, referring generally to  FIG.  132   , the articulation lock gear  21400  rotates in response to the proximal and/or distal longitudinal movement of the articulation actuator  21310  until, as described in greater detail below, the articulation lock gear  21400  is locked in position by the closure member  21110  ( FIG.  134   ). 
     Further to the above, the articulation lock system of the surgical instrument  21000  further comprises a movable lock element  21405  which is slidably mounted to the shaft frame. More specifically, referring primarily to  FIG.  132   , the lock element  21405  comprises a guide projection  21402  extending therefrom which extends into a lateral elongate slot  21403  defined in the shaft frame which is configured to permit the lock element  21405  to slide laterally toward and/or away from the articulation driver  21310 . Moreover, referring primarily to  FIG.  133   , the lock element  21405  slides laterally within an aperture defined in the articulation lock gear  21400  between an unlocked position ( FIG.  132   ) and a locked position ( FIG.  134   ). The lock element  21405  comprises an annular array of lock teeth  21407  and the articulation lock gear  21400  comprises an annular array of lock teeth  21408  defined around the inner aperture thereof and, when the lock element  21405  is in its unlocked position ( FIG.  132   ), the lock teeth  21407  of the lock element  21405  are not engaged with the lock teeth  21408  of the articulation lock gear  21400 . When the lock element  21405  is in its locked position ( FIG.  134   ), the lock teeth  21407  of the lock element  21405  are engaged with the lock teeth  21408  of the articulation lock gear  21400  such that the articulation lock gear  21400  cannot rotate and, as a result, the articulation actuator  21300  is prevented from being moved longitudinally to articulate the end effector  11500 . 
       FIGS.  132 - 134    illustrate the distal progression of the closure member  21110  during a closure stroke.  FIG.  132    illustrates the closure member  21110  in an unactuated, or open, position. In such a position, the closure member  21110  is not engaged with the lock element  21405 .  FIG.  133    illustrates the closure member  21110  in a partially closed position in which the closure member  21110  has at least partially closed the end effector  11500 . In such a position, a cam surface  21115  of the closure member  21110  has engaged the lock element  21405 . In at least one instance, the closure member  21110  moves distally approximately 0.050″ from its open position ( FIG.  132   ) to its partially closed position (PCP) ( FIG.  133   ).  FIG.  134    illustrates the closure member  21110  in a fully closed position (FCP) in which the closure member  21110  has completely closed the end effector  11500 . In such a position, the cam surface  21115  has moved by the lock element  21405  and the lock element  21405  has been displaced by the full thickness of the closure member  21110 . 
     In view of the above, a surgical instrument can include an articulation lock system configured to prevent the end effector of the surgical instrument from being articulated and/or unintentionally back-driven by a load, or torque, applied to the end effector. At least a portion of the articulation lock system can be moved into engagement with an articulation drive system of the surgical instrument to prevent the articulation of the end effector. In at least one instance, an articulation lock can be integral to the articulation drive system, as described in greater detail below. 
     Referring to  FIGS.  135 - 137   , a surgical instrument  22000  comprises a shaft and an articulation drive system  22300  which is configured to articulate an end effector, such as an end effector  11500 , for example, of the surgical instrument  22000  relative to the shaft. The articulation drive system  22300  comprises an articulation driver  22310  and a pinion gear  22320 . The articulation driver  22310  comprises a longitudinal rack of teeth  22316  defined thereon which is operably meshed with teeth  22326  of the pinion gear  22320 . When the articulation driver  22310  is translated distally, the pinion gear  22320  is rotated in a first direction. Correspondingly, the pinion gear  22320  is rotated in a second direction when the articulation driver  22310  is translated proximally. The pinion gear  22320  comprises a bevel gear  22330  fixedly mounted thereto such that the bevel gear  22330  rotates with the pinion gear  22320  about a common axis of rotation. The combined assembly of the pinion gear  22320  and the bevel gear  22330  is rotatably mounted in the shaft of the surgical instrument  22000 . 
     Further to the above, teeth  22336  of the bevel gear  22330  are meshingly engaged with the teeth  22346  of a bevel gear  22340  which is rotatably mounted about a rotatable threaded articulation lead screw  22350 . More specifically, the bevel gear  22340  comprises a nut portion which includes an at least partially threaded aperture which is threadably engaged with the articulation lead screw  22350 . When the bevel gear  22340  is rotated in a first direction by the articulation driver  22310  via the bevel gear  22330 , the bevel gear  22340  rotates the articulation lad screw  22350  in a first direction. Correspondingly, the bevel gear  22340  rotates the articulation lead screw  22350  in a second direction when the bevel gear  22340  is rotated in a second direction. Moreover, the end effector  11500  is rotated in a first direction when the articulation lead screw  22350  is rotated in its first direction and, correspondingly, in a second direction when the threaded articulation driver shaft  22350  is rotated in its second direction. 
     Further to the above, the pitch of the threads on the threaded articulation lead screw  22350  can be selected to prevent back-driving within the articulation drive system  22300 . Stated another way, a steep pitch of the threads defined on the articulation lead screw  22350  would be able to resist a force and/or torque transmitted proximally from the end effector  11500  through the articulation drive system  22300  and, as a result, can prevent the end effector  11500  from being unintentionally articulated. As such, the thread pitch can serve as an articulation lock integral to the articulation drive system  22300 . In at least one instance, the articulation lead screw comprises an ACME lead screw, for example. 
     Referring to  FIGS.  138 - 142   , a surgical instrument  23000  comprises a shaft and an articulation drive system  23300  which is configured to articulate an end effector, such as an end effector  11500 , for example, of the surgical instrument  23000  relative to the shaft. The articulation drive system  23300  comprises an articulation driver  23310  and a pinion gear  23320 . The articulation driver  23310  comprises a longitudinal rack of teeth  23316  defined thereon which is operably meshed with the teeth  23326  of the pinion gear  23320 . When the articulation driver  23310  is translated distally, the pinion gear  23320  is rotated in a first direction. Correspondingly, the pinion gear  23320  is rotated in a second direction when the articulation driver  23310  is translated proximally. The pinion gear  23320  comprises a worm gear  23330  fixedly mounted thereto such that the worm gear  23330  rotates with the pinion gear  23320  about a common axis of rotation. The combined assembly of the pinion gear  23320  and the worm gear  23330  is rotatably mounted in the shaft of the surgical instrument  23000 . 
     Further to the above, teeth  23336  of the worm gear  23330  are meshingly engaged with the teeth  23346  of a worm  23340  which is rotatably mounted to the shaft frame. The worm  23340  comprises a pinion gear  23350  fixedly mounted thereto such that the pinion gear  23350  rotates with the worm  23340  about a common axis of rotation. The pinion gear  23350  is operably engaged with a translatable articulation output driver  23360 . More specifically, the pinion gear  23350  comprises teeth  23356  which are meshingly engaged with a rack of teeth  23366  defined on the output driver  23360 . When the worm  23340  is rotated in a first direction by the articulation driver  23310  via the worm gear  23330 , the pinion gear  23350  drives the output driver  23360  distally. Correspondingly, the worm  23340  and the pinion gear  23350  drive the output driver  23360  proximally when the worm  23340  is rotated in a second direction by the worm gear  23330 . Moreover, the end effector  11500  is rotated in a first direction when the output driver  23350  is driven distally by the articulation drive system  23330  and in a second direction when the output driver  23350  is driven proximally by the articulation drive system  23330 . 
     Further to the above, the pitch of the threads on the worm  23340  can be selected to prevent back-driving within the articulation drive system  23300 . Stated another way, a steep pitch of the threads defined on the worm  23340 , for instance, would be able to resist a force and/or torque transmitted proximally from the end effector  11500  through the articulation drive system  23300  and can prevent the end effector  11500  from being unintentionally articulated. As such, the thread pitch can serve as an articulation lock integral to the articulation drive system  23300 . 
     A surgical instrument  12000 , illustrated in  FIGS.  95 - 97 B , is similar to the surgical instrument  11000  in several respects, many of which will not be repeated herein in the interest of brevity. In addition to a shaft  11100 , an end effector  11500 , and an articulation joint  11200 , the surgical instrument  12000  further comprises a staple firing system  12900 , for example, including a firing bar  12910  extending through the articulation joint  11200 . In use, the firing bar  12910  is translatable distally to perform a staple firing stroke and retractable proximally after at least a portion of the staple firing stroke has been completed. The firing bar  12910  extends through a channel, or slot,  11190  defined in the frame  11180  of the shaft  11100  which is configured to closely receive and/or guide the firing bar  12910  as the firing bar  12910  moves relative to the shaft  11100 . Similarly, the end effector  11500  comprises a channel, or slot,  11590  defined in the frame  11580  of the end effector  11500  which is also configured to closely receive and/or guide the firing bar  12910  as the firing bar  12910  moves relative to the end effector  11500   
     Further to the above, the channels  11190  and  11590  do not extend into the articulation joint  11200  and, without more, the firing bar  12910  may be unsupported within the articulation joint  11200 . When the end effector  11500  is in an unarticulated configuration ( FIG.  97   ), the firing bar  12910  is unlikely to buckle within the articulation joint  11120  during the staple firing stroke—however, the likelihood of the firing bar  12910  buckling laterally during the staple firing stroke increases when the end effector  11500  is in an articulated configuration ( FIGS.  97 A and  97 B ). To reduce the possibility of such buckling, the surgical instrument  12000  further comprises a firing bar support  12400  configured to support the firing bar  12910 . The firing bar support  12400  comprises a proximal portion  12410  connected to the shaft frame  11180 , a distal portion  12430  connected to the end effector frame  11580 , and an intermediate portion  12420  extending between the proximal portion  12410  and the distal portion  12430 . The portions  12410 ,  12420 , and  12430  of the firing bar support  12400  are integrally formed; however, other embodiments are envisioned in which the portions  12410 ,  12420 , and  12430  are assembled to one another and/or comprise separate components. 
     Further to the above, the distal portion  12430  of the firing bar support  12400  is fixedly mounted to the end effector frame  11580  and does not move, or at least substantially move, relative to the end effector frame  11580 . The intermediate portion  12420  of the firing bar support  12400  comprises one or more portions having a reduced cross-section which, among other things, allows the firing bar support  12400  to flex within the articulation joint  11200  when the end effector  11500  is articulated. The proximal portion  12410  of the firing bar support  12400  is slideably mounted to the shaft frame  11180  such that the firing bar support  12400  can translate relative to the shaft frame  11180  when the end effector  11500  is articulated. That said, the proximal portion  12410  of the firing bar support  12400  comprises a proximal head  12415  that is slideable within a chamber, or cavity,  11185  defined within the shaft frame  11180  which can limit the travel of the firing bar support  12400 . Embodiments are envisioned, however, without such a travel constraint. In any event, the proximal portion  12410 , intermediate portion  12420 , and distal portion  12430  of the firing bar support  12400  co-operatively define a channel, or slot,  12490  which is configured to support the firing bar  12910 —especially within the articulation joint  11200 —and reduce the possibility of the firing bar  12910  buckling during the staple firing stroke, for instance. 
     In various instances, the firing bar  12910  is comprised of a plurality of parallel, or at least substantially parallel, layers. The layers are affixed to a distal cutting member and can partially translate or slide longitudinally relative to one another—especially within the articulation joint  11200 . Each such layer is configured to transmit a load in the same direction, i.e., proximally or distally, even though such layers can move, or slide, relative to one another. Further to the above, such layers may splay laterally relative to one another—especially within the articulation joint  11200 —when the end effector  11500  has been articulated. The intermediate portion  12420  of the firing bar support  12400  comprises a plurality of connected control elements which can at least reduce, if not prevent, the relative lateral splay of the firing bar layers. Alternatively, as mentioned above, one or more of the control elements can be unconnected to one another. 
     In addition to or in lieu of the firing bar support  12400 , the surgical instrument  12000  comprises one or more dividers which separate and control the layers of the firing bar  12910 . Referring to  FIGS.  97 - 97 B , the shaft  11110  comprises a divider  12920  positioned within the layers of the firing bar  12910 . Two layers of the firing bar  12910  are positioned on one side of the divider  12920  while two layers are positioned on the other side of the divider  12920 , although any suitable arrangement can be used. The divider  12920  prevents half of the layers of the firing bar  12910  from splaying outwardly when the end effector  11500  is articulated. Stated another way, the divider  12920  prevents the two right-most firing bar layers from splaying to the left when the end effector  11500  is articulated to the right ( FIG.  97 A ) and, similarly, the divider  12920  prevents the two left-most firing bar layers from splaying to the right when the end effector  11500  is articulated to the left ( FIG.  97 B ). The divider  12920  extends through the articulation joint  11200  and the firing bar support  12400  and into the end effector  11500  and can bend when the end effector  11500  is articulated. Accordingly, in such instances, the divider  12920  is flexible. The divider  12920  is mounted to the frame  11180  of the shaft  11110  and does not move relative to the frame  11180 ; however, embodiments are envisioned in which the divider  12920  is not mounted to the frame  11180  and can float within the firing bar layers. 
     A surgical instrument  13000 , illustrated in  FIGS.  98 - 102 B , is similar to the surgical instruments  11000  and  12000  in several respects, many of which will not be repeated herein in the interest of brevity. In addition to a shaft  13100 , an end effector  13500 , and an articulation joint  11200 , the surgical instrument  13000  further comprises a staple firing system  12900 , for example, including a firing bar  12910  extending through the articulation joint  11200 . In use, the firing bar  12910  is translatable distally to perform a staple firing stroke and retractable proximally after at least a portion of the staple firing stroke has been completed. Referring primarily to  FIGS.  102 - 102 B , the firing bar  12910  extends through a channel, or slot,  13190  defined in the frame  13180  of the shaft  13100  which is configured to closely receive and/or guide the firing bar  12190  as the firing bar  12910  moves relative to the shaft  11100 . Similarly, the end effector  13500  comprises a channel, or slot, defined in the frame  13580  of the end effector  13500  which is also configured to closely receive and/or guide the firing bar  12190  as the firing bar  12910  moves relative to the end effector  13500   
     When the end effector  13500  is in an unarticulated configuration ( FIG.  102   ), further to the above, the firing bar  12910  is unlikely to buckle within the articulation joint  11120  during the staple firing stroke—however, the likelihood of the firing bar  12910  buckling laterally during the staple firing stroke increases when the end effector  13500  is in an articulated configuration ( FIGS.  102 A and  102 B ). To reduce the possibility of such buckling, the surgical instrument  13000  further comprises a firing bar support  13400  configured to support the firing bar  12190 . The firing bar support  13400  comprises a first lateral plate  13410  and a second lateral plate  13420 . The lateral plates  13410  and  13420  are positioned on opposite sides of the firing bar  12910 . Each lateral plate  13410 ,  13420  comprises a proximal portion connected to the shaft frame  13180 , a distal portion connected to the end effector frame  13580 , and an intermediate portion extending between the proximal portion and the distal portion. The portions of each plate  13410 ,  13420  are integrally formed; however, other embodiments are envisioned in which the portions are assembled to one another and/or comprise separate components. 
     Further to the above, the first lateral plate  13410  comprises a distal portion  13416  which is fixedly mounted to the end effector frame  13580  and does not move, or at least substantially move, relative to the end effector frame  13580 . Similarly, the second lateral plate  13420  comprises a distal portion  13426  which is fixedly mounted to the end effector frame  13580  and does not move, or at least substantially move, relative to the end effector frame  13580 . The first lateral plate  13410  comprises a proximal portion  13412  which is slideably mounted to the shaft frame  13180  such that the first lateral plate  13410  can translate relative to the shaft frame  13180  when the end effector  13500  is articulated. The proximal portion  13412  comprises a head that is slideable within a chamber, or cavity,  13185  defined within the shaft frame  13180  which can limit the travel of the firing bar support  13400 . Similarly, the second lateral plate  13420  comprises a proximal portion  13422  which is slideably mounted to the shaft frame  13180  such that the firing bar support  13400  can translate relative to the shaft frame  13180  when the end effector  13500  is articulated. The proximal portion  13422  comprises a head that is slideable within the chamber  13185  defined within the shaft frame  13180  which can also limit the travel of the firing bar support  13400 . 
     The first lateral plate  13410  comprises a flexible portion  13414  positioned in the articulation joint  11200  which permits the distal portion  13416  of the first lateral plate  13410  to flex relative to the proximal portion  13412  and accommodate the articulation of the end effector  13500 . The flexible portion  13414  extends laterally from the first lateral plate  13410  and comprises a hinge including gaps  13413  defined therein which permit rotation within the first lateral plate  13410 . In addition to or in lieu of the above, the first lateral plate  13410  comprises longitudinal openings  13415  defined therein which permit the first lateral plate  13410  to flex within the end effector  13500  and accommodate the articulation of the end effector  13500 . The first lateral plate  13410  can comprise any suitable number and configuration of openings and/or recesses defined therein at any suitable location which are configured to permit the first lateral plate  13410  to flex during the articulation of the end effector  13500 . Similarly, the second lateral plate  13412  comprises a flexible portion  13424  positioned in the articulation joint  11200  which permits the distal portion  13426  of the second lateral plate  13420  to flex relative to the proximal portion  13422  and accommodate the articulation of the end effector  13500 . The flexible portion  13424  extends laterally from the first lateral plate  13420  and comprises a hinge including gaps defined therein which permit rotation within the second lateral plate  13420 . In addition to or in lieu of the above, the second lateral plate  13420  comprises longitudinal openings defined therein which permit the second lateral plate  13420  to flex within the end effector  13500  and accommodate the articulation of the end effector  13500 . The second lateral plate  13420  can comprise any suitable number and configuration of openings and/or recesses defined therein at any suitable location which are configured to permit the second lateral plate  13420  to flex during the articulation of the end effector  13500 . 
     Further to the above, the lateral plates  13410  and  13420  are flexible and can resiliently return to their unflexed configurations when the end effector  13500  is returned to its unarticulated configuration. In various instances, the lateral plates  13410  and  13420  comprise springs which resiliently bias the end effector  13500  into its unarticulated configuration. 
     A firing member  24900  is illustrated in  FIGS.  146  and  147    and can be used with any of the surgical stapling instruments disclosed herein. The firing member  24900  comprises a firing bar  24910  which, similar to the above, comprises a plurality of layers. More specifically, the firing bar  24910  comprises two exterior layers  24911  and two interior layers  24912 . The firing member  24900  further comprises a distal cutting member  24920  which includes a tissue cutting edge  24926 . The distal cutting member  24920  further comprises a first cam  24922  configured to engage a first jaw of an end effector and a second cam  24924  configured to engage a second jaw of the end effector. That said, embodiments are envisioned in which the distal cutting member  24920  is configured to only engage one jaw of an end effector or, alternatively, neither jaw of an end effector. 
     The layers  24911  and  24912  of the firing bar  24910  are welded to the distal cutting member  24920  at welds  24930 . As illustrated in  FIG.  147   , a first weld  24930  is present on a first side of the firing member  24900  and a second weld  24930  is present on a second side of the firing member  24900 . The first weld  24930  penetrates a first exterior layer  24911  and the adjacent interior layer  24912 . In various instances, the first weld  24930  penetrates entirely through the adjacent interior layer  24912  and/or also penetrates into the other interior layer  24912 . The second weld  24930  penetrates a second exterior layer  24911  and the adjacent interior layer  24912 . In various instances, the second weld  24930  penetrates entirely through the adjacent interior layer  24912  and/or also penetrates into the other interior layer  24912 . 
     Referring primarily to  FIG.  146   , each weld  24930  of the firing member  24900  comprises a weld line which is configured to securely hold the firing bar  24910  to the cutting member  24920  and, at the same time, provide a flexible connection there between. Each weld  24930  comprises a butt weld  24931  connecting the cutting member  24920  to the distal ends of the plates  24911  and  24912  and is placed in tension and/or compression when a longitudinal firing force is transmitted through the firing member  24900 . The butt weld is orthogonal to, or at least substantially orthogonal to, a longitudinal firing axis (FA) of the firing member  24900 . The butt weld  24931  can comprise any suitable configuration, such as a square, closed square, single-bevel, double-bevel, single-J, double-J, single-V, double-V, single-U, double-U, flange, flare, and/or tee configuration, for example. 
     Further to the above, each weld  24930  further comprises a distal hook weld portion  24932  and a proximal hook weld portion  24933 . Each hook weld portion  24932  and  24933  comprises a longitudinal portion which is aligned with, or is parallel to, the longitudinal firing axis (FA) of the firing member  24900  and is placed in shear when a longitudinal firing force is transmitted through the firing member  24900 . In addition, each hook weld portion  24932  and  24933  comprises a butt portion which is orthogonal, or at least substantially orthogonal, to the longitudinal firing axis (FA) and is placed in tension and/or compression when a longitudinal firing force is transmitted through the firing member  24900 . Notably, each set of hook weld portions  24932  and  24933  comprises an interlocking connection between the firing bar  24910  and the cutting member  24920  which can transmit a flow of stress there between without failing and/or yielding unsuitably. 
     Each weld  24930  is generally L-shaped, for example; however, the welds  24930  can comprise any suitable configuration. 
     Although the surgical instruments  10000 ,  11000 ,  12000 ,  13000 ,  14000 ,  15000 ,  16000 ,  17000 ,  18000 ,  19000 ,  20000 ,  21000 ,  22000 , and  23000  are surgical staplers, their designs can be readily adapted to other surgical instruments having articulatable end effectors, among others. Such other surgical instruments can include, for example, clip appliers, fastener appliers, and/or surgical instruments capable of delivering electrical and/or vibrational energy to tissue. 
       FIG.  149    depicts a surgical staple cartridge  25100  comprising an elongate nose  25150  located at a distal end thereof, generally denoted as  25102 . The elongate nose  25150  has a base  25152  that is defined by a first length  25154  extending a distance between the end of the staple line  25056  and a distal tip  25142  of the staple cartridge  25100 . The distal tip  25142  is formed at an angle σ from the base  25152  of the staple cartridge  25100 . The distal tip  25142  on the staple cartridge  25100  is pointed and configured to serve as a parking area for a wedge sled, not shown, of the firing system upon the completion of a staple firing stroke. 
     In an effort to shorten the overall length of the staple cartridge without sacrificing length of stapled tissue, the surgical staple cartridge  25200  depicted in  FIG.  148    comprises a cartridge body  25210  including a shortened nose  25250  located at a distal end thereof, generally denoted as  25202 . The shortened nose  25250  has a base  25252  that is defined by a second length  25254  extending a distance between the end of the staple line  25056  and a blunted distal tip  25242  of the staple cartridge  25200 . The second length  25254  of the shortened nose  25250  is minimized by blunting the parking area for the wedge sled  25270  (See  FIG.  152   ). While the blunt, shortened nose  25250  of the staple cartridge  25200  in  FIG.  148    still provides a parking area for the wedge sled, additional accommodations for storage may have to be made, as will be discussed below. The blunted distal tip  25242  is formed at an angle γ from the base  25252  of the staple cartridge  25200 . 
     Upon comparing the staple cartridges  25200  and  25100  depicted in  FIGS.  148  and  149   , respectively, the reader should recognize that the second length  25254  is shorter than the first length  25154 . As a result, the length of the staple cartridge  25200  beyond the end of the staple line  25056  is minimized to allow for improved spatial access within a surgical site, among other things. The shortened nose  25250  also prevents the blunted distal tip  25242  from puncturing a seal on a trocar system, as discussed further below. Furthermore, one will recognize the angle γ of the blunted distal tip  25242  of the staple cartridge  25200  with respect to the base  25252  is greater than the angle σ of the pointed distal tip  25142  of the staple cartridge  25100  with respect to the base  25152 . For example, the blunted distal tip  25242  can extend at an angle of approximately 45-50 degrees with respect to the base  25252  of the staple cartridge  25200 , while the pointed distal tip  25142  can extend at an angle of approximately 30 degrees with respect to the base  25152  of the staple cartridge  25100 . The steeper angle of the blunted distal tip  25242  provides increased stability throughout distal regions of the structure of the staple cartridge  25200 . 
       FIG.  152    is a plan view of the staple cartridge  25200 . The cartridge body  25210  of the staple cartridge  25200  comprises an elongate slot  25230  that extends from a proximal end  25204  of the staple cartridge  25200  toward the distal, shortened nose  25250 . A plurality of staple cavities  25220  are formed within the cartridge body  25210 . Staple cavities  25220  extend between the proximal end  25204  and the distal end  25202  of the staple cartridge  25200 . The staple cavities  25220  are arranged in six laterally-spaced longitudinal rows  25221 ,  25222 ,  25223 ,  25224 ,  25225 ,  25226 , with three rows on each side of the elongate slot  25230 . Removably positioned within the staple cavities  25220  are staples  25260 . 
       FIG.  150    illustrates one embodiment of a triple staple driver  25240  within the staple cartridge  25200  for supporting and driving three staples  25260 . The staple driver  25240  comprises a first driver portion  25342 , a second driver portion  25344 , and a third driver portion  25346 . A central base member  25348  connects the first driver portion  25342  and the third driver portion  25346  to the second driver portion  25344 . The first driver portion  25342  is positioned at least partially distal to the second driver portion  25344 . Additionally, the third driver portion  25346  is positioned at least partially distal to the second driver portion  25344 . A plurality of first staple drivers  25240  are slidably mounted within corresponding staple cavities  25220  from the three longitudinal rows  25221 ,  25222 ,  25223  on one side of the elongate slot  25230 . In other words, each first staple driver  25240  is configured to support three staples  25260 : a staple  25260  stored within a staple cavity  25220  in the first longitudinal row  25221 ; a staple  25260  stored within a staple cavity  25220  in the second longitudinal row  25222 ; and a staple  25260  stored within a staple cavity  25220  in the third longitudinal row  25223 . Due to the distal position of the first driver portion  25342  and the third driver portion  25346  relative to the second driver portion  25344 , the staples  25260  are fired in a reverse arrow configuration. As shown in  FIG.  152   , the last staples  25260  in the first longitudinal row  25221  and the third longitudinal row  25223  are closer to the shortened nose  25250  of the staple cartridge  25200  than the last staple  25260  in the second longitudinal row  25222 . 
     On the other side of the elongate slot  25230 , a plurality of second staple drivers are mounted within corresponding staple cavities  25220  in the three longitudinal rows  25224 ,  25225 ,  25226 . Similar to the staple driver  25240 , the second staple drivers each comprise a first driver portion  25342 , a second driver portion  25344 , and a third driver portion  25346 . A central base member  25348  connects the first driver portion  25342  and the third driver portion  25346  to the second driver portion  25344 . The first driver portion  25342  is positioned at least partially distal to the second driver portion  25344 . Additionally, the third driver portion  25346  is positioned at least partially distal to the second driver portion  25344 . As the staple driver  25240  above, each second staple driver is configured to support three staples  25260 : a staple  25260  stored within a staple cavity  25220  in the fourth longitudinal row  25224 , a staple  25260  stored within a staple cavity  25220  in the fifth longitudinal row  25225 , and a staple  25260  stored within a staple cavity  25220  in the sixth longitudinal row  25226 . Due to the distal position of the first driver portion  25342  and the third driver portion  25346  relative to the second driver portion  25344 , the staples  25260  are fired in a reverse arrow configuration. As shown in  FIG.  152   , the last staples  25260  in the fourth longitudinal row  25224  and the sixth longitudinal row  25226  are closer to the shortened nose  25250  of the staple cartridge  25200  than the last staple  25260  in the fifth longitudinal row  25225 . 
     The first driver portion  25342  of the staple driver  25240  has a first forward support column  25352  and a first rearward support column  25354  protruding upward from a first driver portion base. The first forward support column  25352  and the first rearward support column  25354  are spaced from each other and collectively form a first staple cradle for supporting a staple  25260  in an upright position (i.e., the prongs of the staple facing the anvil). Similarly, the second driver portion  25344  has a second forward support column  25362  and a second rearward support column  25364  protruding upward from a second driver portion base. The second forward support column  25362  and the second rearward support column  25364  are spaced from each other and collectively form a second staple cradle for supporting a staple  25260  in an upright position (i.e., the prongs of the staple facing the anvil). The third driver portion  25346  has a third forward support column  25372  and a third rearward support column  25374  protruding upward from a third driver portion base. The third forward support column  25372  and the third rearward support column  25374  are spaced from each other and collectively form a third staple cradle for supporting a staple  25260  in an upright position (i.e., the prongs of the staple facing the anvil). 
     The center of mass of the first and third driver portions  25342 ,  25346  is represented by the dashed line D-D. Similarly, the dashed line P-P represents the center of mass of the second driver portion  25344 . The combined center of mass of the triple staple driver  25240  is represented in  FIGS.  150  and  151    as dashed line C-C. As such, staple driver  25240  is less likely to roll forward. Notably, C-C is closer to D-D than P-P which makes the staple driver  25240  very stable. 
     As discussed above, the central base member  25348  of the staple driver  25240 , depicted in  FIG.  151   , attaches the first driver portion  25342  and the third driver portion  25346  to the second driver portion  25344 . The central base member  25348  extends laterally between the proximal ends of the first and third rearward support columns  25354 ,  25374  on the first and third driver portions  25342 ,  25346 , respectively, and the proximal end of the second forward support column  25362  on the second driver portion  25344 . As can be seen in  FIG.  153   , the central base member  25348  has an angled rearwardly facing edge  25349  adapted to be engaged by a wedge sled  25270 , as will be discussed in further detail below. Due to the extension of the central base member  25348  between all three driver portions  25342 ,  25344 ,  25346 , the midpoint of the rearwardly facing edge  25349  may be bifurcated into a portion which is closer to the first portion  25342  and a portion which is closer to the third portion  25346 . Such an arrangement can balance moments created during the firing and formation of the staples  25260  stored within the staple cavities  25220 . 
     Referring primarily to  FIG.  152   , each staple cavity  25220  defined in the cartridge body  25210  of the staple cartridge  25200  comprises a proximal wall  25264  and a distal wall  25262 . The reverse arrow orientation formed by the arrangement of the first, second, and third driver portions  25342 ,  25344 ,  25346  of the triple staple driver  25240  discussed above, reduces forward and/or lateral roll of the staple driver  25240  during a staple firing stroke. In various instances, the distal end of the first forward support column  25352  and the distal end of the third forward support column  25372  are pushed into the distal walls  25262  of their respective staple cavities  25220 , which stabilize the driver  25240 . Thus, when the sled  25270  ( FIG.  152   ) lifts the staple driver  25240  upwardly during the staple firing stroke, two distal walls  25262  of the staple cavities  25220  provide an opposing force against the forward support columns  25352 ,  25372 , preventing any unwanted movement or rolling of the staple driver  25240 . 
     As illustrated in  FIGS.  150 - 153   , the elongate slot  25230  of the staple cartridge  25200  is configured to receive a portion of a firing assembly  25280 . The firing assembly  25280  is configured to push the sled  25270  distally to eject the staples  25260  stored within the staple cavities  25220  and deform the staples  25260  against an anvil positioned opposite the staple cartridge  25200 . More specifically, a coupling member  25282  pushes the wedge sled  25270  of the staple cartridge  25200  distally. The wedge sled  25270  has four rails, two inner rails  25272  and two outer rails  25274  which are connected to each other by a central member  25276 . One inner rail  25272  and one outer rail  25274  are positioned on one side of the elongate slot  25230 , while the other inner rail  25272  and the other outer rail  26274  are positioned on the opposite side of the elongate slot  25230 . When driven distally, the inner rails  25272  pass through inner channels  25212  defined within the cartridge body  25210  and engage the rearwardly facing edge  25349  of the drivers  25240  supporting the staples  25260  to cause the firing of the staples toward the anvil. Likewise, the outer rails  25274  pass through outer channels  25214  defined within the cartridge body  25210  and engage portions of the drivers  25240  supporting the staples  25260  to push the staples toward the anvil. Distal movement of the wedge sled  25270  causes the rails  25272 ,  25274  to make contact with the rearwardly facing edges  25349  of the staple drivers  25240 , pushing drivers  25240  upwards to eject the staples  25260  from the staple cartridge  25200  into tissue captured between the staple cartridge  25200  and an opposing anvil. The coupling member  25282  also comprises a cutting edge  25284  which incises the tissue as the coupling member  25282  is advanced distally to eject the staples  25260  from the cartridge body  25210 . 
     Referring again to  FIG.  150   , the positioning of the first, second, and third driver portions  25342 ,  25344 ,  25346  of the staple driver  25240  between or adjacent an inner rail  25272  and an outer rail  25274  of the wedge sled  25270  provides increased lateral stability. Two rails, one inner rail  25272  and one outer rail  25274 , straddle the staple driver  25240 , providing increased support and stability of throughout a firing stroke. In addition to providing enhanced stability to the staple driver  25240 , another benefit of having a staple driver  25240  spanning across two rails  25272 ,  25274  of a wedge sled  25270  is a reduced force required to perform a firing stroke. The required force is decreased as there is less deflection and loss within the system. Additionally, the additional drive surface provided by the rearwardly facing edge  25349  allows for the rails  25272 ,  25274  of the wedge sled  25270  to extend at a steeper angle from the base  25278  of the wedge sled  25270 . The steeper angle of the wedge sled  25270  allows for an overall decrease in the length of the base  25278  of the wedge sled  25270 , further contributing to the reduction in length of the shortened nose  25250  of the staple cartridge  25200 . Upon the completion of the staple firing stroke, referring again to  FIG.  152   , the wedge sled  25270  of the firing assembly  25280  is parked within the shortened nose  25250  of the staple cartridge  25200 . 
       FIG.  152    depicts the wedge sled  25270  of the firing assembly  25280  parked in the shortened nose  25250  upon the completion of the staple firing stroke. The shortened nose  25250  comprises a plurality of openings  25292 ,  25294  at the distal end of the shortened nose  25250  to receive the four rails  25272 ,  25274 . The shortened nose  25250  further comprises an opening  25296  configured to receive the central sled member  25276  of the wedge sled  25270 . Thus, portions of the rails  25272 ,  25274  and central sled member  25276  of the wedge sled  25270  are exposed at the distal end  25202  of the staple cartridge  25200 . The openings  25292 ,  25294  are continuations of the channels  25212 ,  25214  within which the rails  25272 ,  25274  of the wedge sled  25270  slidably travel. Two inner openings  25292  are configured to receive the two inner rails  25272  of the wedge sled  25270 , while two outer openings  25294  are configured to receive the two outer rails  25274  of the wedge sled  25270 . A central opening  25296  in the center of the distal portion  25202  of the shortened nose  25250  is configured to receive the central member  25276  of the wedge sled  25270 . The openings  25292 ,  25294 ,  25296  at the distal end  25202  of the shortened nose  25250  allow for the staple firing stroke to be completed and for the wedge sled  25270  to be parked in a shortened distal end. 
     Referring again to  FIG.  152   , the staple cartridge  25200  further includes projections  25262  extending around the proximal and distal ends of the staple cavities  25220 . The projections  25262  in the first longitudinal row  25221  are shown to be singular, while the projections in the second and third longitudinal rows  25222 ,  25223  are shown to be connected. The projections  25262  are configured to provide additional support to the staples  25260  as they are fired upwardly out of their staple cavities  25220 . Furthermore, the projections  25264  formed on the distalmost staple cavity  25220  are ramped to control the flow of tissue into the end effector. A more detailed discussion of the projections can be found in U.S. Patent Application Publication No. 2015/0297228, entitled FASTENER CARTRIDGES INCLUDING EXTENSIONS HAVING DIFFERENT CONFIGURATIONS, filed on Jun. 30, 2014, the entire disclosure of which is incorporated by reference. 
       FIG.  154    illustrates some of the advantages gained by using the shortened staple cartridge  25200  from  FIG.  148    instead of the elongate staple cartridge  25100  from  FIG.  149   . Both staple cartridges are suitable for various surgical procedures, including, for example, Low Anterior Resection Surgery (LAR). LAR is a common treatment for colorectal cancer, for example. Such procedures require precise dissection and sealing of tissue deep within the pelvic cavity of a patient. As will be discussed in more detail below, the shortened length of the staple cartridge  25200 , owing to the shortened nose  25250  in  FIG.  148   , among other things, allows the end effector of the surgical instrument to gain greater access to tissue within the pelvic cavity. The reader should understand that the staple cartridges described herein can be used in various surgical treatments and are not to be limited by the specific procedures discussed herein. 
     Further to the above, the short staple cartridge  25200  is part of a first end effector  25202  on a first surgical instrument  25201  which also includes an anvil  25203 . The first surgical instrument  25201  further comprises a first shaft  25206  that is rotatably connected to the first end effector  25202 . The first end effector  25202  is articulatable about an articulation joint  25208  positioned intermediate the first end effector  25202  and the first shaft  25206 . The first end effector  25202  is capable of being articulated to an angle α with respect to the first shaft  25206 . Similarly, the elongate staple cartridge  25100  is part of a second end effector  25102  on a second surgical instrument  25101  which also includes an anvil  25103 . Also, the second surgical instrument  25101  further comprises a second shaft  25106  that is rotatably connected to the second end effector  25102 . The second end effector  25102  is articulatable about an articulation joint  25108  positioned intermediate the second end effector  25102  and the second shaft  25106 . The second end effector  25102  is capable of being articulated to an angle β with respect to the second shaft  25106 . 
     Further to the above, in use, a clinician inserts the end effector  25202  through a cannula, or trocar, and into a patient when the end effector  25202  is in its unarticulated condition. Once through the trocar, the end effector  25202  can be articulated as illustrated in  FIG.  154   . At such point, the shaft  25206  can be moved to position the end effector  25202  in the pelvic cavity. Similar steps would be used to position the end effector  25102 . 
     The first end effector  25202  is able to reach a distance X 1  from the pelvic floor within the pelvic cavity during a LAR procedure. The second end effector  25102  is able to reach a distance X 2  from the pelvic floor within the pelvic cavity during a LAR procedure. Distance X 1  is shorter than distance X 2 , allowing the first surgical instrument  25201  to be placed deeper into the pelvic cavity than the second surgical instrument  25101 , giving the surgeon the capability to, among other things, target, access, and remove a greater array of diseased tissue from the colon. Additionally, the articulation capabilities of the first surgical instrument  25201  allow deeper access to tissue within the surgical site while inflicting minimal trauma to surrounding tissue. The first end effector  25202  is able to be articulated to a greater degree than the second end effector  25102 , as β is larger than α. For example, the first end effector  25202  may be articulated to an angle 115 degrees from the first shaft  25206 , while the second end effector  25102  may only be articulated to an angle 135 degrees from the second shaft  25106 . 
     As illustrated in  FIG.  154   , the staple cartridge  25100  and the anvil  25103  of the end effector  25102  have approximately the same length, but the staple cartridge  25100  is noticeably longer than the anvil  25103 . Comparatively, the staple cartridge  25200  and the anvil  25203  of the end effector  25202  are substantially the same length, if not the same length. In any event, the difference in length between the staple cartridge  25200  and the anvil  25203  of the end effector  25202 , if any, is much smaller than the end effector  25102 . 
     An extreme difference between the distal end of a staple cartridge and a distal end of an anvil can cause damage to a trocar when the end effector is inserted there through. Referring to  FIG.  155   , an end effector  25810  comprises a distal end  25802 , an anvil  25820 , and a staple cartridge  25830 . The staple cartridge  25830  has a blunt, shortened nose  25840  similar to the shortened nose  25250  on the staple cartridge  25200  in  FIG.  148   . As can be seen in  FIGS.  155  and  156   , the anvil  25820  has a protective tip  25822  thereon. The protective tip  25822  is sized and positioned on the anvil  25820  in a way that causes the anvil  25820  to be shorter in length than the staple cartridge  25830 . Thus, the shortened nose  25840  of the staple cartridge  25830  extends distally relative to the anvil  25820 . The protective tip  25822  may be integrally formed (molded, machined, etc.) on the distal end  25802  of the anvil  25820  or it may comprise a separate piece configured to receive a complementary portion of the anvil. A more extensive discussion of protective tips can be found U.S. Patent Application Publication No. 2008/0169328, entitled IMPROVED BUTTRESS MATERIAL FOR USE WITH A SURGICAL STAPLER, the entire disclosure of which is hereby incorporated by reference in its entirety. 
     As can be seen in  FIGS.  155  and  156   , the protective tip  25822  of the anvil  25820  has a first curved, or angled, outer surface  25824  and a second curved, or angled, outer surface  25826  configured to form a stubby distal end on the anvil  25820 . The first angled outer surface  25824  extends downwardly from a top surface  25828  of the anvil  25820  at a first angle ϕ. The second angled outer surface  25826  extends downwardly from the first angled outer surface  25824  toward the staple cartridge  25830  at a second angle θ. The second angle θ is greater than the first angle ϕ. Various embodiments are envisions in which angle θ is approximately 90 degrees, for example. Other embodiments of the protective tip  25822  are envisioned having only one of either a first angled outer surface  25824  or a second angled outer surface  25826 . The first angled outer surface  25824  serves to deflect a centering ring of a trocar seal assembly during the insertion of the end effector  25810  through the trocar. When the second angle θ gets farther from 90 degrees, and/or when the first and second curved outer surfaces  25824 ,  25826  are not continuous, the anvil  25820  might pierce through a trocar seal or can displace the centering ring of a trocar seal system, as will be discussed in greater detail below. 
     A protective tip can be attached to an anvil in any suitable manner.  FIGS.  157 - 162    illustrate exemplary embodiments of separately formed protective tips  25922 ,  26022 , and various methods for their attachment to an anvil. As depicted in  FIGS.  157 - 159   , a distal portion of an anvil  25920  comprises an attachment feature including attachment members  25927 ,  25929  which are configured to retainingly mate with complementary retention channels  25926 ,  25928  formed in the protective tip  25922 . More specifically, a central retention channel  25928  is formed within the protective tip  25922  to receive a central attachment member  25929  of the anvil  25920 . A pair of side retention channels  25296  is formed within the protective tip  25922  to receive a pair of corresponding side attachment members  25927  on the anvil  25920 .  FIG.  159    is a cross-sectional view of the anvil  25920  of  FIG.  157    taken along the line  159 - 159  in  FIG.  158    in a disassembled configuration showing the alignment of the retention channels  25926 ,  25928  with their respective attachment members  25927 ,  25929 . An elongate slot  25994  extends longitudinally from the proximal end  25904  of the anvil  25920  toward the distal end  25902  of the anvil  25920 . The elongate slot  25994  is configured to receive a portion of the firing assembly discussed herein. 
     In addition, or in the alternative, to the above, the protective tip  25922  may be secured to the anvil  25920  using rivets  25924 . As shown in  FIG.  159   , a through-hole  25925  extends through the central retention channel  25928  of the protective tip  25922 . A through-hole  25925  also extends through the central attachment member  25929  of the anvil  25920  so that when the protective tip  25922  is attached to the anvil  25920 , the through-holes  25925  line up to facilitate the insertion of a rivet  25924  therein.  FIG.  158    is a cross-sectional view of the anvil  25920  of  FIG.  157    taken along line  158 - 158  in  FIG.  157    in a disassembled configuration illustrating a rivet assembly for removably affixing the protective tip  25922  to the anvil  25920 . In addition, or in the alternative, to the above, the protective tip  25922  may be affixed to the anvil  25920  by adhesives such as, for example, cyanoacrylates, light-curable acrylics, polyurethanes, silicones, epoxies, and/or ultra-violet curable adhesives such as HENKEL LOCTITE®. In any event, a combination of attachment members and retention channels may be provided on the anvil  25920  and the protective tip  25922 . Still other forms of attachments and attachment arrangements may be used to affix the protective tip  25922  to the anvil  25920 . 
       FIGS.  160 - 162    illustrate another embodiment of a tip attachment arrangement. A distal portion of an anvil  26020  comprises attachment members  26027  configured to retainingly mate with complementary retention channels  26026  defined in the protective tip  26022 . In addition, a central retention channel  26028  defined within the protective tip  26022  is configured to receive a central attachment member  26029  of the anvil  26020 .  FIG.  161    is a cross-sectional view of the anvil  26020  of  FIG.  160    taken along the line  161 - 161  in  FIG.  160    in a disassembled configuration showing the alignment of the retention channels  26026 ,  26028  with their respective attachment members  26027 ,  26029 .  FIG.  162    is a cross-sectional view of the anvil  26020  of  FIG.  160    taken along the line  162 - 162  in  FIG.  160    in an assembled configuration. The protective tip  26022  is secured to the anvil  26020  using a compression fit. The central attachment member  26029  is press-fit into the central retention channel  26028 , remaining in place due to the geometry of the central retention channel  26028 . The central attachment member  26029  of the anvil  26020  in  FIG.  161    has a trapezoidal shape that is mimicked by the central retention channel  26028 . An elongate slot  26094  extends longitudinally from a proximal end  26004  of the anvil  26020  toward the distal end  26002  of the anvil  26020 . The elongate slot  26094  is configured to receive a portion of the firing assembly discussed herein. 
     In addition, or in the alternative, to the above, the protective tip  26022  may be affixed to the anvil  26020  by adhesives such as, for example, cyanoacrylates, light-curable acrylics, polyurethanes, silicones, epoxies, and/or ultra-violet curable adhesives such as HENKEL LOCTITE®, for example. In various embodiments, a combination of attachment members and retention channels may be provided on the anvil  26020  and the protective tip  26022 . Still other forms of attachments and attachment arrangements may be used to affix the protective tip  26022  to the anvil  26020 .  FIGS.  160 - 162    further illustrate means for assisting a user in attaching the protective tip  26022  to the anvil  26020 .  FIG.  160    illustrates the protective tip  26022  removably positioned within a temporary holder  26030 . In order to releasably affix the protective tip  26022  to the anvil  26020 , the user presses the temporary holder  26030  and the anvil  26020  together. The temporary holder  26030  may provide an additional sterilization barrier to the protective tip  26022  while the protective tip  26022  is affixed to the anvil  26020 . Furthermore, the temporary holder  26030  provides the user with an object that is more substantial to hold onto while attaching the protective tip  26022  to the anvil  26020 , as the protective tip  26022  may be small in size. It is envisioned that the temporary holder  26030  can be used across various embodiments of protective tips, including the other embodiments disclosed herein. 
     Various protective anvil tips have been described and depicted herein as being used in connection with a linear end effector. Those of ordinary skill in the art will readily appreciate, however, that the protective anvil tips described herein may be used in connection with a variety of different end effector configurations such as curved end effectors and other types of end effectors without departing from the spirit and scope of the present disclosure. Thus, the protective tip described above should not be limited solely to use in connection with linear end effectors and/or staplers. 
       FIGS.  163 - 169    illustrate an exemplary practical application of the various end effectors described herein when they are inserted through a trocar seal system prior to being introduced into a surgical site. The trocar seal system  27040  of  FIGS.  163 - 169    comprises a housing  27042  configured to support a floating seal assembly  27050  and a central opening  27044  configured to receive a surgical instrument. The floating seal assembly  27050  comprises a first seal door  27052  and a second seal door  27054  that work together to prohibit gas from escaping from an insufflated cavity in a patient during a surgical procedure. The floating seal assembly  27050  further comprises a centering ring  27058  which is configured to guide a surgical instrument through the central opening  27044  of the trocar seal system  27040 . The floating seal assembly  27050  is attached to the housing  27042  of the trocar seal system  27040  through an annular resilient member  27056 . 
       FIG.  163    depicts an end effector  27000  comprising an anvil  27010  and a staple cartridge  27020 . The staple cartridge  27020  comprises a blunt, shortened nose  27022 , similar to the shortened nose  25250  depicted on the staple cartridge  25200  in  FIG.  148   . The distal end  27202  of the anvil  27010  is pointed and does not have a protective tip, such as that shown in  FIG.  155   . As can be seen in  FIG.  163   , the anvil  27010  is shorter in length than the staple cartridge  27020 . In other words, the shortened nose  27022  of the staple cartridge  27020  extends longitudinally beyond the distal end  27002  of the anvil  27010 . Prior to inserting the end effector  27000  through the trocar seal system  27040 , the first seal door  27052  and the second seal door  27054  extend inwardly to prevent gas from escaping from the surgical site.  FIG.  164    depicts the end effector  27000  of  FIG.  163    partially inserted into the trocar seal system  27040 . The shortened nose  27022  of the staple cartridge  27020  is the first component of the end effector  27000  to come into contact with the first and second seal doors  27052 ,  27054  of the trocar seal system  27040 , tilting the floating seal assembly  27050  to one side. Due to its blunt shape, the shortened nose  27022  does not damage the second seal door  27054  despite exerting a force on it. 
       FIG.  165    depicts the end effector  27000  of  FIGS.  163  and  164    when the end effector  27000  has been further introduced into the central opening  27044  of the trocar seal system  27040 . After the initial contact of the shortened staple cartridge nose  27022  with the trocar seal system  27040 , the pointed distal end  27002  of the anvil  27010  contacts the first seal door  27052  of the trocar seal system  27040 . In various instances, the pointed distal end  27002  of the anvil  27010  can rupture the first seal door  27052  of the trocar seal system  27040 , as the contact between the shortened nose  27022  and the second seal door  27054  has already shifted the position of the floating seal assembly  27050  laterally. As illustrated in  FIG.  166   , had the distal end  27002  of the anvil  27010  comprised a protective tip  27012  similar to the protective tip  25822  shown in  FIG.  155   , the risk of rupturing the first seal door  27052  would have been reduced. The risk of rupture decreases with the use of a protective tip  27012  on the anvil  27010 , as the first seal door  27052  will smoothly stretch around the protective tip  27012 . Moreover, the same length of the cartridge and the anvil reduces, or prevents, the pre-shifting of the floating seal assembly. 
       FIG.  167    depicts an end effector  27100  comprising an anvil  27110  and a staple cartridge  27120 . The staple cartridge  27120  comprises a pointy, elongate nose  27122 , similar to the elongate nose  25150  depicted on the staple cartridge  25100  in  FIG.  149   . The distal end  27102  of the anvil  27110  is pointed and does not have a protective tip, such as that shown in  FIG.  155   . The anvil  27110  is shorter in length than the staple cartridge  27120 . In other words, the elongate nose  27122  of the staple cartridge  27120  extends longitudinally beyond the distal end  27102  of the anvil  27110 . Prior to the insertion the end effector  27100  through the trocar seal system  27040 , the first seal door  27052  and the second seal door  27054  of the trocar seal system  27040  extend inwardly to prevent gas from escaping the surgical site.  FIG.  168    depicts the end effector  27100  of  FIG.  167    when the end effector  27100  is initially inserted into the trocar seal system  27040 . The elongate nose  27122  of the staple cartridge  27120  is the first component of the end effector  27100  to come into contact with the first and second seal doors  27052 ,  27054  of the trocar seal system  27040 , tilting, or pre-shifting, the floating seal assembly  27050  to one side as discussed above. 
       FIG.  169    depicts the end effector  27100  of  FIGS.  167  and  168    when the end effector  27100  has been further introduced into the central opening  27044  of the trocar seal system  27040 . After the initial contact of the elongate nose  27122  of the staple cartridge  27120 , the pointed distal end  27102  of the anvil  27110  contacts the first seal door  27052  of the trocar seal system  27040 . In various instances, the pointed distal end  27102  of the anvil  27110  may rupture the first seal door  27052  of the trocar seal system  27040 , as the contact between the elongate nose  27122  and the second seal door  27054  displaced the position of the floating seal assembly  27050 . 
     As discussed herein, a first staple cartridge can comprise a first cartridge length and a second staple cartridge can comprise a second cartridge length which is different than the first cartridge length. In various instances, an end effector of a surgical stapling instrument can comprise a cartridge jaw configured to receive the first staple cartridge and, in the alternative, the second staple cartridge. Stated another way, the cartridge jaw is configured to receive the first staple cartridge and the second staple cartridge, but not at the same time. The first staple cartridge and the second staple cartridge each comprise a proximal end which is aligned with a proximal cartridge jaw datum when it is positioned in the cartridge jaw. When the first cartridge length is longer than the second cartridge length, for instance, the distal end of the first staple cartridge would be positioned further away from the proximal cartridge jaw datum than the distal end of the second staple cartridge. The reader should understand that the second cartridge length can be longer than the first cartridge length in other instances. 
     Further to the above, the end effector comprises an anvil jaw movable relative to the cartridge jaw between an open, or unclamped, position, and a closed, or clamped, position. In alternative embodiments, the cartridge jaw is movable relative to the anvil jaw. In either event, the anvil jaw comprises a distal anvil end which is supported by the first staple cartridge and the second staple cartridge, depending on which staple cartridge is positioned in the cartridge jaw. The distal anvil end is supported at a first location on the first cartridge jaw and at a second location on the second cartridge jaw. In various instances, the first location and the second location may not be the same distance from the proximal cartridge jaw datum. In some instances, however, they can be the same distance from the proximal cartridge jaw datum. Moreover, in various instances, the first location is located a first distance away from the distal end of the first staple cartridge while the second location is located a second, or different, distance away from the distal end of the second staple cartridge. In use, the tissue of a patient will be positioned between the anvil jaw and the cartridge jaw but, nonetheless, the support locations of the staple cartridges will still support the anvil jaw, or the clamping load applied by the anvil jaw. 
     In various instances, further to the above, the distal anvil end can extend distally beyond the distal end of the first staple cartridge when the end effector is in a clamped configuration and the first staple cartridge is positioned in the cartridge jaw and, similarly, the distal anvil end can extend distally beyond the distal end of the second staple cartridge when the end effector is in a clamped configuration and the second staple cartridge is positioned in the cartridge jaw. However, when the first cartridge length is longer than the second cartridge length, in various instances, the distal anvil tip can extend distally beyond the distal end of the second staple cartridge but not extend distally beyond the distal end of the first staple cartridge. In such instances, the anvil jaw can be longer than the second staple cartridge when the second staple cartridge is positioned in the cartridge jaw but shorter than the first staple cartridge when the first staple cartridge is positioned in the cartridge jaw. In some instances, the anvil jaw is the same length as the first staple cartridge or the second staple cartridge. 
     Further to the above, the anvil jaw will deflect when it is moved into its clamped position. Owing to the different cartridge lengths of the staple cartridges, the deflection of the anvil jaw may be different depending on which staple cartridge is positioned in the cartridge jaw. As a result, the staple forming gap between the anvil jaw and the staple drivers of the first cartridge jaw can be different than the staple forming gap between the anvil jaw and the staple drivers of the second cartridge jaw. In some instances, the difference in staple forming gap is negligible, and the staples ejected from the first staple cartridge and the second staple cartridge will be formed to the same, or at least suitable, heights and sufficiently staple the tissue captured between the anvil jaw and the cartridge jaw. In such instances, the unformed height of the staples in the first staple cartridge can be the same as the unformed height of the staples in the second staple cartridge. In other instances, the unformed height of the staples in the first staple cartridge is different than the unformed height of the staples in the second staple cartridge. In such instances, taller staples can be used in the first staple cartridge and shorter staples can be used in the second staple cartridge, for example, depending on the anticipated deflection and/or orientation of the anvil jaw when clamped against the first and second staple cartridges. In at least one such instance, each of the staples in the first staple cartridge has an unformed height in a first unformed height range and each of the staples in the second staple cartridge has an unformed height in a second unformed height range. In some instances, the first unformed height range is completely different than the second unformed height range while, in other instances, the first unformed height range partially overlaps the second unformed height range. 
     As discussed above, the first staple cartridge and the second staple cartridge are selectively positioned in the cartridge jaw of the end effector and, further to the above, the cartridge jaw further comprises a bottom support or surface configured to support the staple cartridges when they are seated in the cartridge jaw. Such a support can comprise a vertical datum. In various instances, the first support location on the first staple cartridge and the second support location on the second staple cartridge, discussed above, are the same vertical distance from the vertical datum of the cartridge jaw. The vertical distance is measured orthogonally from the vertical datum, but can be measured in any suitable manner. In other instances, the first support location on the first staple cartridge has a different vertical height than the second support location on the second staple cartridge. In such instances, the orientation and/or deflection of the anvil jaw when the anvil jaw is in its clamped position can be different as a result of the first support location and the second support location having different vertical heights. Such different vertical heights can occur when the distal end, or nose, of the first staple cartridge is different than the distal end of the second staple cartridge, among other reasons. 
     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. 
     The entire disclosures of:
     U.S. Pat. No. 5,403,312, entitled ELECTROSURGICAL HEMOSTATIC DEVICE, which issued on Apr. 4, 1995;   U.S. Pat. No. 7,000,818, entitled SURGICAL STAPLING INSTRUMENT HAVING SEPARATE DISTINCT CLOSING AND FIRING SYSTEMS, which issued on Feb. 21, 2006;   U.S. Pat. No. 7,422,139, entitled MOTOR-DRIVEN SURGICAL CUTTING AND FASTENING INSTRUMENT WITH TACTILE POSITION FEEDBACK, which issued on Sep. 9, 2008;   U.S. Pat. No. 7,464,849, entitled ELECTRO-MECHANICAL SURGICAL INSTRUMENT WITH CLOSURE SYSTEM AND ANVIL ALIGNMENT COMPONENTS, which issued on Dec. 16, 2008;   U.S. Pat. No. 7,670,334, entitled SURGICAL INSTRUMENT HAVING AN ARTICULATING END EFFECTOR, which issued on Mar. 2, 2010;   U.S. Pat. No. 7,753,245, entitled SURGICAL STAPLING INSTRUMENTS, which issued on Jul. 13, 2010;   U.S. Pat. No. 8,393,514, entitled SELECTIVELY ORIENTABLE IMPLANTABLE FASTENER CARTRIDGE, which issued on Mar. 12, 2013;   U.S. patent application Ser. No. 11/343,803, entitled SURGICAL INSTRUMENT HAVING RECORDING CAPABILITIES, now U.S. Pat. No. 7,845,537;   U.S. patent application Ser. No. 12/031,573, entitled SURGICAL CUTTING AND FASTENING INSTRUMENT HAVING RF ELECTRODES, filed Feb. 14, 2008;   U.S. patent application Ser. No. 12/031,873, entitled END EFFECTORS FOR A SURGICAL CUTTING AND STAPLING INSTRUMENT, filed Feb. 15, 2008, now U.S. Pat. No. 7,980,443;   U.S. patent application Ser. No. 12/235,782, entitled MOTOR-DRIVEN SURGICAL CUTTING INSTRUMENT, now U.S. Pat. No. 8,210,411;   U.S. patent application Ser. No. 12/249,117, entitled POWERED SURGICAL CUTTING AND STAPLING APPARATUS WITH MANUALLY RETRACTABLE FIRING SYSTEM, now U.S. Pat. No. 8,608,045;   U.S. patent application Ser. No. 12/647,100, entitled MOTOR-DRIVEN SURGICAL CUTTING INSTRUMENT WITH ELECTRIC ACTUATOR DIRECTIONAL CONTROL ASSEMBLY, filed Dec. 24, 2009, now U.S. Pat. No. 8,220,688;   U.S. patent application Ser. No. 12/893,461, entitled STAPLE CARTRIDGE, filed Sep. 29, 2012, now U.S. Pat. No. 8,733,613;   U.S. patent application Ser. No. 13/036,647, entitled SURGICAL STAPLING INSTRUMENT, filed Feb. 28, 2011, now U.S. Pat. No. 8,561,870;   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;   U.S. patent application Ser. No. 13/524,049, entitled ARTICULATABLE SURGICAL INSTRUMENT COMPRISING A FIRING DRIVE, filed on Jun. 15, 2012, now U.S. Pat. No. 9,101,358;   U.S. patent application Ser. No. 13/800,025, entitled STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, filed on Mar. 13, 2013, now U.S. Pat. No. 9,345,481;   U.S. patent application Ser. No. 13/800,067, entitled STAPLE CARTRIDGE TISSUE THICKNESS SENSOR SYSTEM, filed on Mar. 13, 2013, now U.S. Patent Application Publication No. 2014/0263552;   U.S. Patent Application Publication No. 2007/0175955, entitled SURGICAL CUTTING AND FASTENING INSTRUMENT WITH CLOSURE TRIGGER LOCKING MECHANISM, filed Jan. 31, 2006; and   U.S. Patent Application Publication No. 2010/0264194, entitled SURGICAL STAPLING INSTRUMENT WITH AN ARTICULATABLE END EFFECTOR, filed Apr. 22, 2010, now U.S. Pat. No. 8,308,040, are hereby incorporated by reference herein.   

     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. 
     Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials do not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.