Linear stapler with improved firing stroke

• US 5,697,543 A
• Filed: 03/12/1996
• Issued: 12/16/1997
• Est. Priority Date: 03/12/1996
• Status: Expired due to Term

• Current Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Original Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Inventors: Burdorff, Mark A.
• Primary Examiner(s): Smith, Scott A.
• Application Number:
  US08/614,216
• Time in Patent Office: 644 Days
• Field of Search: 227/19, 227/175.1, 227/176.1, 227/178.1
• US Class Current: 227/176.1
• CPC Class Codes: A61B 17/072 for applying a row of staples in a single action , e.g. the staples being applied simultaneously
• CPC Class Codes: A61B 17/07207 the staples being applied sequentially

Abstract

A linear stapler particularly adapted for open surgical procedures is disclosed. Staples are fired when tissue is clamped between the cartridge and anvil of the staple fastening assembly of the stapler, and the firing trigger is pivotally rotated in a counterclockwise direction from an unfired position to a fired position adjacent the hand grip of the frame of the stapler. Resistance to the pivotal rotation of the firing trigger independent of the staple fastening assembly is provided to inhibit the surgeon from inadvertently firing the staples or partially firing the staples from the cartridge against the anvil. The firing bar is sandwiched between two spacer plates secured to the firing bar, and a stationary slot pin must overcome the resistance of detents displayed on slots in the spacer plates when the firing bar is moved distally to fire the staples. An audible signal is also provided to alert the surgeon when staples have been fully fired. One of the spacer plates has a signal spring and pin which interacts with a signal ramp attached within the frame. As staples are being fired, the ramp deflects the pin, and when firing is complete, the spring disengages from the ramp and impacts the inside of the frame to provide an audible signal. Although the invention is described in connection with an open linear stapler, it is broadly applicable to other surgical fastening instruments, including endoscopic linear staplers.

Claims

1. A surgical stapling instrument comprising:

a) a frame at a first end of said instrument for gripping and manipulating said instrument, said frame having a body portion and a hand grip descending from said body portion thereof;

b) a staple fastening assembly at an opposite end of said instrument, said staple fastening assembly including a cartridge displaying a plurality of vertical rows of slots for containing staples therein, and an anvil facing said cartridge for forming staples from said cartridge thereon, said cartridge and anvil movable towards each other from a spaced position for positioning tissue therebetween to a closed position for clamping the tissue;

c) first and second elongated structural plates spaced from each other, said structural plates coupling said frame to said staple fastening assembly;

d) a clamping and firing transmission assembly fitted between said structural plates, said clamping and firing transmission assembly including first and second elongated closure plates spaced from each other, said first closure plate adjacent said first structural plate and said second closure plate adjacent said second structural plate, and an elongated firing bar fitted between said closure plates;

e) a clamping actuator at said frame and operatively connected to said clamping and firing transmission assembly, wherein when said clamping actuator is actuated, said clamping and firing transmission assembly moves distally causing said cartridge and anvil to move from their spaced position to their closed position for clamping the tissue;

f) a firing trigger pivotally mounted to said body portion of said frame for pivotal counterclockwise rotation from an unfired position spaced from said hand grip to a fired position adjacent said hand grip, wherein when said firing trigger is stated from said unfired position to said fired position, said firing bar of said clamping and firing transmission assembly moves distally causing firing of said staples from said cartridge against said anvil for staple formation;

g) first and second elongated spacer plates, said first spacer plate fitted between said first closure plate and said firing bar, and said second spacer plate fitted between said second closure plate and said firing bar, said spacer plates being secured to said firing bar; and

h) means in communication with said clamping and firing transmission assembly independent of said staple fastening assembly for providing resistance to the distal movement of said firing bar when said firing trigger is pivotally rotated from said unfired position to said fired position;

wherein;

each of said closure and spacer plates, and said firing bar, has an elongated slot therein with proximal and distal ends;

each closure plate slot has a first length, and each spacer plate slot and said firing bar slot has a second length, said second length being greater than said first length; and

when said cartridge and anvil are in their spaced position, each of said slot distal ends is mutually aligned.

2. The instrument of claim 1 further comprising:

h) means in communication with said clamping and firing transmission assembly independent of said staple fastening assembly for providing a signal when said firing trigger is rotated to said fired position.

3. The instrument of claim 2 wherein said signal is an audible signal.

4. The instrument of claim 3 further comprising:

j) a stationary slot pin fixed to each of said structural plates through each of said slots;

wherein when said cartridge and anvil are in their spaced position, said stationary slot pin is initially located adjacent each of said slot distal ends;

when said clamping actuator is actuated to move said clamping and firing transmission assembly distally causing said cartridge and anvil to move to their closed position, each of said slots moves distally over said first length, and said stationary slot pin is intermediately located adjacent said slot proximal ends of each of said closure plates; and

when said firing trigger is thereafter pivotally rotated to move each of said spacer plates and said firing bar distally so as to fire said staples, said slots of each of said spacer plates and said firing bar move distally from an intermediate slot position, and said stationary slot pin is finally located adjacent said slot proximal ends of each of said spacer plates and said firing bar.

5. The instrument of claim 4 wherein said resistance means includes first and second detents displayed on said elongated slots of each of said spacer plates, each of said detents is located adjacent said intermediate slot position, and when said firing trigger is pivotally rotated to fire said staples, each of said detents moves distally across said stationary slot pin.

6. The instrument of claim 5 wherein each of said spacer plate slots has upper and lower ledges, and each of said detents has a proximal and distal protruding surface extending from said upper and lower ledges, said distal protruding surface being generally perpendicular to said upper and lower ledges, and said proximal protruding surface being sloped in relation to said upper and lower ledges.

7. The instrument of claim 6 wherein said signal means includes:

a signal spring extending from one of said spacer plates, said signal spring having a signal pin thereon; and

a signal ramp having a sliding surface thereon attached within said body portion of said frame;

wherein when said firing trigger is pivotally rotated from said unfired position, said signal spring is deflected as said signal pin slides on said sliding surface of said signal ramp; and

when said firing trigger is pivotally rotated to said fired position, said signal pin slides off said sliding surface so as to deflect said pin against said body portion of said frame.

8. A surgical stapling instrument comprising:

a) a frame at a first end of said instrument for gripping and manipulating said instrument, said frame having a body portion and a hand grip descending from said body portion thereof;

b) a staple fastening assembly at an opposite end of said instrument, said staple fastening assembly including a cartridge displaying a plurality of vertical rows of slots for containing staples therein, an anvil facing said cartridge for forming said staples from said cartridge thereon, said cartridge and anvil movable towards each other from a spaced position for positioning tissue therebetween to a closed position for clamping the tissue;

c) a firing transmission assembly including an elongated firing bar interposed between said body portion of said frame and said staple fastening assembly;

d) a firing trigger pivotally mounted to said body portion of said frame for pivotal counterclockwise rotation from an unfired position spaced from said hand grip to a fired position adjacent said hand grip, wherein when said cartridge and anvil are in their closed position and said firing trigger is rotated from said unfired position to said fired position, said firing bar of said firing transmission assembly moves distally causing firing of staples from said cartridge against said anvil for staple formation;

e) a stationary slot pin fixed between said body portion of said frame and said staple fastening assembly, said stationary slot pin being received through an elongated slot in said firing transmission assembly; and

f) a detent displayed on said elongated slot in said firing transmission assembly, and when said firing trigger is pivotally rotated to move said firing transmission assembly distally so as to fire said staples, said detent moves distally across said stationary slot pin so as to provide resistance to the distal movement of said firing bar.

9. The instrument of claim 8 further comprising:

f) means in communication with said firing transmission assembly independent of said staple fastening assembly for providing a signal when said firing trigger is rotated to said fired position.

10. The instrument of claim 9 wherein said signal is an audible signal.

11. The instrument of claim 10 wherein said detent has proximal and distal protruding surfaces extending from said elongated slot.

12. The instrument of claim 11 wherein said signal means includes:

a signal spring movable with said firing bar, said signal spring having a signal pin thereon; and

a signal ramp having a sliding surface thereon attached within said body portion of said frame;

wherein when said firing trigger is pivotally rotated from said unfired position, said signal spring is deflected as said signal pin slides on said sliding surface of said signal ramp; and

when said firing trigger is pivotally rotated to said fired position, said signal pin slides off said sliding surface so as to deflect said pin against said body portion of said frame.