Surgical instruments with progressive jaw closure arrangements
A surgical instrument that includes a first jaw and a second jaw that are movable between a closed position and an open position. An axially movable closure member is supported relative to the jaws to apply closing and opening motions thereto. A closure actuator operably interfaces with the closure member and is movable from an unactuated position corresponding to the open position in a closure direction during a closure procedure. A first control system is configured to apply an opening control motion to the closure actuator to return the closure actuator to the unactuated position upon completion of the closure procedure. A second control system is configured to apply a variable closure force to the closure member as the closure actuator is moved in the closure direction.
1. A surgical instrument, comprising:
a surgical end effector comprising:
a first jaw; and
a second jaw movable relative to said first jaw between an open position and a closed position;
a frame defining a cavity, wherein said frame comprises a distal frame wall;
a shuttle movable within said cavity between an unactuated position and an actuated position, wherein said shuttle comprises a proximal shuttle wall and a distal shuttle wall, wherein a first spring space is defined by said distal frame wall and said distal shuttle wall, and wherein a second spring space is defined by said distal shuttle wall and said proximal shuttle wall;
an actuator comprising a closure shaft, wherein said actuator is movable between a proximal position corresponding to said open position of said second jaw and a distal position corresponding to said closed position of said second jaw, wherein said actuator is configured to drive said second jaw toward said closed position based on said actuator moving toward said distal position, and wherein said actuator is axially movable relative to said shuttle;
a first spring positioned in said first spring space, wherein said first spring is configured to engage said distal shuttle wall to bias said shuttle proximally toward the unactuated position to move said second jaw toward said open position, and wherein said first spring is compressed by said distal shuttle wall and said distal frame wall based on said shuttle moving toward said actuated position; and
a second spring positioned in said second spring space, wherein said second spring is configured to bias a proximal portion of said closure shaft against said distal shuttle wall, wherein said second spring is configured to advance said actuator distally from said proximal position toward said distal position to apply a closure motion to said second jaw based on said shuttle moving toward said actuated position, wherein said second spring is compressed by said proximal shuttle wall and said actuator based on said shuttle moving toward said actuated position, and wherein said first spring comprises a first spring coefficient and wherein said second spring comprises a second spring coefficient that is greater than said first spring coefficient.
2. The surgical instrument of claim 1 , wherein said second spring is configured to increase the closure motion to said second jaw based on an amount of resistance experienced by said second jaw.
3. The surgical instrument of claim 1 , further comprising an axially movable knife, wherein said axially movable knife is configured to move between a starting position corresponding to the open position of said second jaw and an ending position, and wherein said axially movable knife is configured to retain said second jaw in the closed position as said axially movable knife is moved from the starting position to the ending position.
4. The surgical instrument of claim 3 , further comprising:
a motor-driven axially movable firing beam movably supported within said shuttle, wherein said motor-driven axially movable firing beam is configured to move relative to said shuttle in response to a firing motion and a retraction motion applied thereto, and wherein said motor-driven axially movable firing beam operably interfaces with said axially movable knife; and
a firing system operably interfacing with said motor-driven axially movable firing beam, wherein said firing system is configured to apply the firing motion and the retraction motion to said motor-driven axially movable firing beam based on said second jaw being in the closed position.
5. The surgical instrument of claim 1 , wherein said second spring coefficient is up to ten times greater than said first spring coefficient.
6. The surgical instrument of claim 1 , wherein said actuator comprises at least one opening feature configured to engage a corresponding opening portion on said second jaw to apply an opening motion thereto based on said actuator moving in a proximal direction.
7. The surgical instrument of claim 6 , wherein said closure shaft defines a shaft axis and comprises a hollow closure tube comprising a closure tube distal end and a closure tube proximal end, and wherein said at least one opening feature comprises:
a first opening feature formed in said hollow closure tube on one side of the shaft axis;
and a second opening feature formed in said hollow closure tube on another side of the shaft axis, and wherein said second opening feature is axially offset from said first opening feature.
8. The surgical instrument of claim 1 , wherein said frame comprises a handheld housing, and wherein said actuator comprises an elongate shaft assembly operably coupling said handheld housing to said surgical end effector, wherein the elongate shaft assembly comprises the closure shaft.
9. The surgical instrument of claim 8 , wherein said elongate shaft assembly defines a shaft axis, and wherein said surgical end effector is operably coupled to said elongate shaft assembly for selective articulation relative to a portion of said elongate shaft assembly about an articulation axis that is transverse to the shaft axis.
10. The surgical instrument of claim 9 , further comprising an articulation drive system comprising:
a proximal link assembly movably supported for selective axial travel along the shaft axis; and
a distal link pivotally coupled to said proximal link assembly and said surgical end effector, wherein said distal link extends transversely across the shaft axis.
11. The surgical instrument of claim 10 , wherein said articulation drive system further comprises a drive motor operably interfacing with said proximal link assembly.
12. The surgical instrument of claim 1 , further comprising a manually actuatable trigger operably interfacing with said shuttle to selectively move said shuttle from the unactuated position to the actuated position.
13. The surgical instrument of claim 1 , wherein said first spring space comprises a first axial length, wherein said second spring space comprises a second axial length, and wherein said first axial length is greater than said second axial length when said shuttle is in said unactuated position.
14. The surgical instrument of claim 13 , wherein said second axial length is fixed.
15. A surgical instrument, comprising:
a housing defining a cavity, wherein said housing comprises a housing wall;
an end effector operably coupled to said housing, wherein said end effector comprises:
a first jaw; and
a second jaw movable between an open position and a closed position relative to said first jaw;
an axially movable closure tube movable between a first position corresponding to said open position of said second jaw and a second position corresponding to said closed position of said second jaw, wherein said axially movable closure tube is configured to move said second jaw toward the closed position based on the axially movable closure tube moving toward said second position;
a closure actuator movable within said cavity between an unactuated position and an actuated position, wherein said closure actuator comprises a first actuator wall and a second actuator wall, wherein a first spring space is defined between said first actuator wall and said housing wall, and wherein a second spring space is defined by said first actuator wall and said second actuator wall;
a first biasing member positioned in said first spring space, wherein said first biasing member is configured to apply an opening motion to said first actuator wall to move said closure actuator toward the unactuated position, and wherein said first biasing member is compressed by said first actuator wall and said housing wall based on said closure actuator moving toward said actuated position; and
a second biasing member positioned in said second spring space, wherein said second biasing member is configured to bias a proximal portion of said closure tube against said first actuator wall, wherein said second biasing member is configured to apply a variable amount of a closure force to said axially movable closure tube based on an amount of closure resistance experienced by said second jaw as said second jaw moves toward said closed position, wherein said second biasing member is configured to advance said axially movable closure tube from said first position toward said second position based on said closure actuator moving toward said actuated position, and wherein said second biasing member is compressed by said second actuator wall and said axially movable closure tube based on said closure actuator moving toward said actuated position, wherein said first biasing member comprises a first spring coefficient and wherein said second biasing member comprises a second spring coefficient that is greater than said first spring coefficient.
16. The surgical instrument of claim 15 , wherein said first jaw comprises a surgical staple cartridge, and wherein said second jaw comprises an anvil.
17. The surgical instrument of claim 16 , wherein said first jaw comprises an elongated channel configured to removably support said surgical staple cartridge therein.
18. A surgical instrument, comprising:
an end effector, comprising:
a first jaw; and
a second jaw movable relative to said first jaw between an open position and a closed position;
a frame comprising a distal frame wall;
a shuttle movable within said frame between an unactuated position and an actuated position, wherein said shuttle comprises a proximal shuttle wall and a distal shuttle wall, wherein a first spring space is defined between said distal frame wall and said distal shuttle wall, and wherein a second spring space is defined between said distal shuttle wall and said proximal shuttle wall;
a closure driver movable between a proximal position corresponding to the open position of said second jaw and a distal position corresponding to the closed position of said second jaw, wherein said closure driver is configured to drive said second jaw toward the closed position based on said closure driver moving toward said distal position, and wherein said closure driver is axially movable relative to said shuttle;
a first spring positioned in said first spring space, wherein said first spring is configured to bias said shuttle toward the unactuated position to move said second jaw toward the open position, and wherein said first spring is compressed by said distal shuttle wall based on said shuttle moving toward said actuated position; and
a second spring positioned in said second spring space, wherein said second spring is configured to advance said closure driver distally from said proximal position toward said distal position based on said shuttle moving toward said actuated position, and wherein said first spring comprises a first spring coefficient, and wherein said second spring comprises a second spring coefficient less than said first spring coefficient.
19. The surgical instrument of claim 18 , wherein said first spring is engaged with said distal frame wall and said distal shuttle wall, and wherein said second spring is engaged with said closure driver and said proximal shuttle wall.
20. The surgical instrument of claim 18 , wherein said first spring is journaled on said closure driver.