Motor-driven surgical cutting instrument

Abstract

A motor-driven surgical cutting and fastening instrument that comprises an end effector, an electric motor, and a motor control circuit. The motor control circuit is for monitoring a parameter of the electric motor that is indicative of movement of a moveable member of the end effector, and for adjustably controlling the electric motor based on the monitored parameter to thereby adjustably control movement of the moveable member of the end effector during forward rotation of the electric motor.

1 - 20 . (canceled) 
     
     
         21 . A surgical stapler, comprising:
 a handle;   a shaft extending from said handle;   a surgical end effector extending from said shaft, wherein said surgical end effector comprises a replaceable staple cartridge;   a firing member configured to move through a plurality of positions during a firing stroke;   an electric motor configured to drive said firing member during the firing stroke;   a control system for controlling said electric motor, said control system comprising:
 a battery configured to supply pulses to said electric motor; 
 a pulse width modulation circuit configured to control the duration of pulses supplied from said battery to said electric motor and optimize the speed applied to said firing member from said electric motor; 
   wherein said firing member is configured to move at least partially through said surgical end effector during the firing stroke at a firing speed, wherein said pulse width modulation circuit is configured to reduce the speed of said firing member to below the firing speed at various times during the firing stroke, and wherein said surgical end effector further comprises:
 a proximal end; and 
 a distal end, wherein said pulse width modulation circuit is configured to modulate the speed of said firing member below the firing speed as said firing member approaches said distal end. 
   
     
     
         22 . The surgical stapler of  claim 21 , further comprising a firing member position sensor configured to detect a plurality of positions of said firing member, wherein said pulse width modulation circuit is configured to control said electric motor based on the detected positions of said firing member. 
     
     
         23 . The surgical stapler of  claim 21 , wherein said firing member further comprises a cutting element configured to translate in said surgical end effector. 
     
     
         24 . The surgical stapler of  claim 21 , wherein said pulse width modulation circuit is configured to modulate the speed of said firing member to below the firing speed as said firing member travels within a lockout region. 
     
     
         25 . The surgical stapler of  claim 21 , wherein said pulse width modulation circuit is configured to modulate the speed of said firing member to below the firing speed during an initial range of positions. 
     
     
         26 . A surgical instrument, comprising:
 a handle;   a shaft extending from said handle;   a surgical end effector extending from said shaft;   a firing member configured to move between a proximal position and a distal position during a firing stroke, wherein said firing member is configured to move at a firing speed during a portion of the firing stroke;   a battery-powered motor configured to drive said firing member during the firing stroke; and   a control system comprising a pulse width modulation circuit configured to control the duration of pulses supplied to said battery-powered motor, wherein said pulse width modulation circuit is configured to modulate the speed of said firing member to below the firing speed at various times during the firing stroke including when said firing member approaches the distal position.   
     
     
         27 . The surgical instrument of  claim 26 , further comprising a firing member position sensor configured to detect a plurality of positions of said firing member, wherein said pulse width modulation circuit is configured to control the duration of pulses based on the detected positions of said firing member. 
     
     
         28 . The surgical instrument of  claim 26 , wherein said firing member further comprises a cutting element configured to translate in said surgical end effector. 
     
     
         29 . The surgical instrument of  claim 26 , wherein said surgical end effector comprises a staple. 
     
     
         30 . The surgical instrument of  claim 26 , further comprising a replaceable staple cartridge positioned in said surgical end effector. 
     
     
         31 . The surgical instrument of  claim 26 , wherein said pulse width modulation circuit is configured to modulate the speed of said firing member to below the firing speed as said firing member travels within a lockout region. 
     
     
         32 . The surgical instrument of  claim 26 , wherein said pulse width modulation circuit is configured to modulate the speed of said firing member to below the firing speed during an initial range of positions. 
     
     
         33 . A surgical instrument, comprising:
 a handle;   a shaft extending from said handle;   a surgical end effector extending from said shaft;   a firing member configured to move between a proximal position and a distal position during a firing stroke;   a battery-powered motor configured to drive said firing member during the firing stroke; and   a control system comprising a pulse width modulation circuit configured to control the duration of pulses supplied to said battery-powered motor, wherein said firing member is configured to move at a speed when pulses of a first duration are supplied to said battery-powered motor, wherein said pulse width modulation circuit is configured to reduce the duration of pulses to less than the first duration at various times during the firing stroke including as said firing member approaches the distal position.   
     
     
         34 . The surgical instrument of  claim 33 , further comprising a firing member position sensor configured to detect a plurality of positions of said firing member, wherein said pulse width modulation circuit is configured to control the duration of pulses based on the detected positions of said firing member. 
     
     
         35 . The surgical instrument of  claim 33 , wherein said firing member further comprises a cutting element configured to translate in said surgical end effector. 
     
     
         36 . The surgical instrument of  claim 33 , wherein said surgical end effector comprises a staple. 
     
     
         37 . The surgical instrument of  claim 33 , further comprising a replaceable staple cartridge positioned in said surgical end effector. 
     
     
         38 . The surgical instrument of  claim 33 , wherein the duration of pulses is reduced to less than the first duration as said firing member travels within a lockout region. 
     
     
         39 . The surgical instrument of  claim 33 , wherein the duration of pulses is reduced to less than the first duration during an initial range of positions.