Surgical stapler with mechanisms for reducing the firing force

Claim 2

A surgical stapler for applying staples to compressed tissue comprising: a handle portion having surfaces adapted to be manually grasped by a surgeon; a cartridge retention portion and an anvil retention portion, means for mounting said cartridge retention portion and said anvil retention portion for relative movement between a closed position in which said cartridge retention portion and said anvil retention portion are in closely spaced relationship for clamping tissue to be stapled therebetween and an open position in which said cartridge retention portion and said anvil retention portion are spaced farther from each other than in the closed position, an anvil having a plurality of specially shaped surfaces, said cartridge retention portion having a staple housing for enclosing six rows of staples in substantially parallel, linear rows having proximal and distal ends, said six rows being spaced laterally across the staple housing such that any line drawn laterally across the staple line crosses at least three staples, staple drivers adjacent staples, and a plurality of pushers each having camming surfaces, said staple housing being elongate to define a longitudinal axis, said staple housing having a plurality of longitudinally extending pusher slots adapted to receive said pushers to afford movement of said pushers in a firing direction between pre-fired and fired positions, and a plurality of driver channels for receiving said staple drivers to afford movement of said staple drivers in a staple driving direction between pre-eject and ejected positions; and each of said staple drivers having a cam follower surface for engaging the camming surface of a pusher to move the staple driver from the pre-eject toward the ejected position to substantially sequentially eject the staples in a row from the staple housing and press the ejected staples against the specially shaped surfaces of the anvil to engage, form and close staples in tissue clamped between the staple housing and the anvil.

Claim 3

A surgical stapler for applying staples to compressed tissue comprising: a handle portion having surfaces adapted to be manually grasped by a surgeon; a cartridge retention portion and an anvil retention portion, means for mounting said cartridge retention portion and said anvil retention portion for relative movement between a closed position in which said cartridge retention portion and said anvil retention portion are in closely spaced relationship for clamping tissue to be stapled therebetween and an open position in which said cartridge retention portion and said anvil retention portion are spaced farther from each other than in the closed position, an anvil having a plurality of specially shaped surfaces, said cartridge retention portion having a staple housing for enclosing six adjacent rows of staples in substantially parallel, linear rows, the distance between adjacent staples in the same row defining a staple pitch P, said six rows being spaced such that each row is longitudinally offset from all of the other rows, staple drivers adjacent staples, and a plurality of pushers each having camming surfaces, said staple housing being elongate to define a longitudinal axis, said staple housing having a plurality of longitudinally extending pusher slots adapted to receive said pushers to afford movement of said pushers in a firing direction between pre-fired and fired positions, and a plurality of driver channels for receiving said staple drivers to afford movement of said staple drivers in a staple driving direction between pre-eject and ejected positions; each of said staple drivers having a cam follower surface for engaging the camming surface of a pusher to move the staple driver from the pre-eject toward the ejected position to substantially sequentially eject the staples in a row from the staple housing and press the ejected staples against the specially shaped surfaces of the anvil to engage, form and close staples in tissue clamped between the staple housing and the anvil.

Claim 4

A surgical stapler for applying staples to compressed tissue comprising: a handle portion having surfaces adapted to be manually grasped by a surgeon; a cartridge retention portion and an anvil retention portion, means for mounting said cartridge retention portion and said anvil retention portion for relative movement between a closed position in which said cartridge retention portion and said anvil retention portion are in closely spaced relationship for clamping tissue to be stapled therebetween and an open position in which said cartridge retention portion and said anvil retention portion are spaced farther from each other than in the closed position, an anvil having a plurality of specially shaped surfaces, said cartridge retention portion having a staple housing for enclosing six adjacent rows of staples in substantially parallel, linear rows, the distance between adjacent staples in the same row defining a staple pitch P, said six rows being spaced such that each row is longitudinally offset from all of the other rows, staple drivers adjacent staples, and a plurality of pushers each having camming surfaces, said staple housing being elongate to define a longitudinal axis, said staple housing having a plurality of longitudinally extending pusher slots adapted to receive said pushers to afford movement of said pushers in a firing direction between pre-fired and fired positions, and a plurality of driver channels for receiving said staple drivers to afford movement of said staple drivers in a staple driving direction between pre-eject and ejected positions; each of said staple drivers having a cam follower surface for engaging the camming surface of a pusher to move the staple driver from the pre-eject toward the ejected position to substantially sequentially eject the staples in a row from the staple housing and press the ejected staples against the specially shaped surfaces of the anvil to engage, form and close staples in tissue clamped between the staple housing and the anvil.

Claim 5

A surgical stapler according to claim 2 wherein the staples in each of the rows are longitudinally offset at least 1/6 of the pitch P from any staple in any of the other rows.

Claim 6

A surgical stapler according to claim 3 wherein one of the rows is longitudinally offset 1/3 of the pitch from each of the adjacent rows.

Claim 7

A surgical stapler for applying staples to compressed tissue comprising: a handle portion having surfaces adapted to be manually grasped by a surgeon; a cartridge retention portion and an anvil retention portion, means for mounting said cartridge retention portion and said anvil retention portion for relative movement between a closed position in which said cartridge retention portion and said anvil retention portion are in closely spaced relationship for clamping tissue to be stapled therebetween and an open position in which said cartridge retention portion and said anvil retention portion are spaced farther from each other than in the closed position, an anvil having a plurality of specially shaped surfaces, said cartridge retention portion having a staple housing for enclosing six rows of staples in substantially parallel, linear rows, the distance between adjacent staples in the same row defining a staple pitch P, said six rows of staples being separated into a first set of three parallel linear rows and a second set of three parallel linear rows by a centerline, each of the three parallel linear rows of staples in the first set being spaced such that it is longitudinally offset from the other two rows of staples in the first set, each of the three parallel linear rows of staples in the second set being spaced such that it is longitudinally offset from the other two rows of staples in the second set, staple drivers adjacent staples, and a plurality of pushers each having camming surfaces, said staple housing being elongate to define a longitudinal axis, said staple housing having a plurality of longitudinally extending pusher slots adapted to receive said pushers to afford movement of said pushers in a firing direction between pre-fired and fired positions, and a plurality of driver channels for receiving said staple drivers to afford movement of said staple drivers in a staple driving direction between pre-eject and ejected positions; and each of said staple drivers having a cam follower surface for engaging the camming surface of a pusher to move the staple driver from the pre-eject toward the ejected position to substantially sequentially eject the staples in a row from the staple housing and press the ejected staples against the specially shaped surfaces of the anvil to engage, form and close staples in tissue clamped between the staple housing and the anvil.

Claim 8

A surgical stapler for applying staples to compressed tissue comprising: a handle portion having surfaces adapted to be manually grasped by a surgeon; a cartridge retention portion and an anvil retention portion, means for mounting said cartridge retention portion and said anvil retention portion for relative movement between a closed position in which said cartridge retention portion and said anvil retention portion are in closely spaced relationship for clamping tissue to be stapled therebetween and an open position in which said cartridge retention portion and said anvil retention portion are spaced farther from each other than in the closed position, an anvil having a plurality of specially shaped surfaces, said cartridge retention portion having a staple housing for enclosing six rows of staples in substantially parallel, linear rows, the distance between adjacent staples in the same row defining a staple pitch P, said six rows of staples being separated into a first set of three parallel linear rows and a second set of three parallel linear rows by a centerline, each of the three parallel linear rows of staples in the first set being spaced such that it is longitudinally offset from the other two rows of staples in the first set, each of the three parallel linear rows of staples in the second set being spaced such that it is longitudinally offset from the other two rows of staples in the second set, staple drivers adjacent staples, and a plurality of pushers each having camming surfaces, said staple housing being elongate to define a longitudinal axis, said staple housing having a plurality of longitudinally extending pusher slots adapted to receive said pushers to afford movement of said pushers in a firing direction between pre-fired and fired positions, and a plurality of driver channels for receiving said staple drivers to afford movement of said staple drivers in a staple driving direction between pre-eject and ejected positions; and each of said staple drivers having a cam follower surface for engaging the camming surface of a pusher to move the staple driver from the pre-eject toward the ejected position to substantially sequentially eject the staples in a row from the staple housing and press the ejected staples against the specially shaped surfaces of the anvil to engage, form and close staples in tissue clamped between the staple housing and the anvil.

Claim 9

A surgical stapler according to claim 5 wherein at least one of said rows of staples in said first set is longitudinally aligned with one of said rows of staples in said second set.

Claim 10

A surgical stapler according to claim 5 wherein said first set of rows is a mirror image of said second set of rows.