Cobalt base alloy end effectors for laparoscopic surgical scissors

Claim 2

A scissors device comprising: a) a pair of investment cast homogeneous scissor elements each comprised of a cobalt based alloy, each said investment cast homogeneous scissor element having in its as-cast form an elongate portion having an integral cutting edge and an adjacent base portion, and at least one of said investment cast homogeneous scissor elements having a through-hole in said base portion transverse to said elongate portion, wherein said pair of investment cast homogeneous scissor elements are laterally offset one to the other with respective said integral cutting edges oppositely adjacent each other, and each said scissor element has a length, a height, and a thickness, said height being less than about 0.4 inches, and said thickness being less than about 0.2 inches; and b) a pivot means extending transverse said pair of investment cast homogeneous scissor elements and extending through said through-hole of said at least one of said scissor elements, said pivot means for permitting pivoting of at least one of said pair of investment cast homogeneous scissor elements relative to the other or said pair of scissor elements.

Claim 3

A scissors device according to claim 1, wherein: said cobalt base alloy is a cobalt base super alloy.

Claim 4

A scissors device according to claim 2, wherein: said cobalt base alloy contains about 20 to 30% by weight chromium, and said cobalt base alloy contains at least about 38% by weight cobalt.

Claim 5

A scissors device according to claim 3, wherein: said cobalt base alloy contains about 0.45 to 0.55% by weight carbon.

Claim 6

A scissors device according to claim 4, wherein: said cobalt base alloy consists essentially of, in weight percent, about 25-29% Cr, 2-3% Fe, 5-6% Mo, up to 0.04% P,, up to 0.007% B, up to 1% Ni, up to 1% Mn, up to 1% Bi, balance Co and trace amounts of incidental impurities.

Claim 7

A scissors device according to claim 5, wherein: said cobalt base alloy consists essentially of 28.6% Cr, 2.7% Fe, 5.3% Mo, 0.54% C, 0.25% Ni, 0.91% Bi, 0.5% Mn, less than 0.01% P, 0.005% S, 0.005% B, balance Co in an amount of at least 61.2%.

Claim 8

A scissors device according to claim 1, wherein: said cobalt base alloy contains at least about 38% by weight cobalt.

Claim 9

A scissors device according to claim 1, wherein: said cobalt base alloy contains at least about 50% by weight cobalt.

Claim 10

A scissors device according to claim 1, wherein: each said investment cast homogeneous end effector has a said transverse through-hole, and each said investment cast homogeneous end effector has a length less than about 0.75 inches from said transverse through-hole to the end of said end effector.

Claim 11

A scissors device according to claim 1, wherein: said cutting edge of said element is hard enough to scratch stainless steel.

Claim 12

In a surgical instrument for insertion through a trocar, tube, and having an outer tube having a longitudinal axis, first and second scissor end effector elements coupled to said outer tube, with at least one of said first and second scissor elements rotating around an axis perpendicular to said longitudinal axis, and an actuating means extending through said outer tube and coupled to at least said rotating scissor element for effecting rotation thereof by movement of said actuating means, an improvement comprising: said first and second end effector elements are each comprised of a cobalt base alloy, each end effector in the form of a homogeneous cast blade having in its as-cast form an elongate portion, and at least one of said end effector elements having a through-hole transverse to said elongate portion, said first and second end effector elements being laterally offset relative to each other and having their respective cutting edges opposite each other wherein said rotation of at least one of said first and second end effector elements effects a scissoring action.

Claim 13

In a surgical instrument for insertion through a trocar, tube, and having an outer tube having a longitudinal axis, first and second scissor end effector elements coupled to said outer tube, with at least one of said first and second scissor elements rotating around an axis perpendicular to said longitudinal axis, and an actuating means extending through said outer tube and coupled to at least said rotating scissor element for effecting rotation thereof by movement of said actuating means, an improvement comprising: said first and second end effector elements are each comprised of a cobalt base alloy, each end effector in the form of a homogeneous cast blade having in its as-cast form an elongate portion, and at least one of said end effector elements having a through-hole transverse to said elongate portion, said first and second end effector elements being laterally offset relative to each other and having their respective cutting edges opposite each other wherein said rotation of at least one of said first and second end effector elements effects a scissoring action.

Claim 14

In a surgical instrument according to claim 11, wherein: said surgical instrument further comprises a clevis coupled to said outer tube and having a pivot perpendicular to said longitudinal axis and, said surgical instrument is a double acting instrument, and both said first and second end effector elements have through-holes and are pivotally engaged at their respective through-holes to said pivot, and both said first and second end effector elements are coupled to said actuation means. PG,26

Claim 15

In a surgical instrument according to claim 11, wherein: said cobalt base alloy is a cobalt base superalloy containing at least about 38% by weight cobalt.

Claim 16

In a surgical instrument according to claim 13, wherein: said cobalt base alloy consists essentially of by weight, 25-29% Cr, 2-3% Fe, 5-6% Mo, up to 0.04% P,, up to 0.007% B, up to 1% Ni, up to 1% Mn, up to 1% Bi, balance Co and trace amounts of incidental impurities.

Claim 17

In a surgical instrument according to claim 14, wherein: said cobalt base alloy consists essentially of 28.6% Cr, 2.7% Fe, 5.3% Mo, 0.54% C, 0.25% Ni, 0.91% Bi, 0.5% Mn, less than 0.01% P, 0.005% S, 0.005% B., balance Co in an amount of at least 61.2%.

Claim 18

In a surgical instrument according to claim 11, wherein: said cutting edge of said first and second end effector is hard enough to scratch stainless steel.

Claim 19

In a surgical instrument according to claim 11, wherein: said first and second end effector elements each have a length, a height, and a thickness, said length being less than 0.75 inches from said transverse through-hole to the end of said end effector element, said height being less than 0.40 inches, and said thickness being less than 0.20 inches.

Claim 20

In a surgical instrument according to claim 11, wherein: said cobalt base alloy is a cobalt base super alloy.

Claim 21

In a surgical instrument according to claim 11, wherein: said cobalt base alloy contains about 0.45 to 0.55% by weight carbon.

Claim 22

A surgical scissors, comprising: a) a hollow tube having a first end and a second end; b) a clevis coupled to said first end of said hollow tube; c) two homogeneous cast end effector scissor elements, at least one of said scissor elements pivotally engaging said clevis, said scissor elements being laterally offset relative to each other and having respective cutting edges arranged opposite each other; d) a rod extending at least partially through said hollow tube and having a first end and a second end, said first end of said rod being coupled to at least said scissor element which pivotally engages said clevis; and e) actuating means engaged to said second end of said rod for imparting reciprocal motion to said rod relative to said tube which is translated at said clevis to pivotal motion of said pivotally engaged scissor element, wherein said at least one scissor element which pivotally engages said clevis has a base portion having a through-hole therethrough which is used to couple said rod to said at least one scissor element, and said at least one scissor element which pivotally engages said clevis has a length, a height, and a thickness, said height being less than about 0.4 inches, and said thickness being less than about 0.2 inches, and said two cast end effector scissor elements are comprised of a cobalt base alloy.

Claim 23

A surgical scissors, comprising: a) a hollow tube having a first end and a second end; b) a clevis coupled to said first end of said hollow tube; c) two homogeneous cast end effector scissor elements, at least one of said scissor elements pivotally engaging said clevis, said scissor elements being laterally offset relative to each other and having respective cutting edges arranged opposite each other; d) a rod extending at least partially through said hollow tube and having a first end and a second end, said first end of said rod being coupled to at least said scissor element which pivotally engages said clevis; and e) actuating means engaged to said second end of said rod for imparting reciprocal motion to said rod relative to said tube which is translated at said clevis to pivotal motion of said pivotally engaged scissor element, wherein said at least one scissor element which pivotally engages said clevis has a base portion having a through-hole therethrough which is used to couple said rod to said at least one scissor element, and said at least one scissor element which pivotally engages said clevis has a length, a height, and a thickness, said height being less than about 0.4 inches, and said thickness being less than about 0.2 inches, and said two cast end effector scissor elements are comprised of a cobalt base alloy.

Claim 24

A surgical scissors according to claim 20, wherein: said through-holes in said base portion of said scissor elements are coaxial with each other.

Claim 25

A surgical scissors according to claim 21, wherein: said homogeneous cast end effector scissor elements are investment cast homogeneous elements, said cobalt base alloy is a cobalt base superalloy containing at least about 38% by weight cobalt, and said cutting edges of said end effector scissor elements are hard enough to scratch stainless steel.

Claim 26

A surgical scissors according to claim 20, wherein: said cobalt base alloy is a cobalt base super alloy.

Claim 27

A surgical scissors according to claim 23, wherein: said cobalt base alloy contains at least about 38% by weight cobalt.

Claim 28

A surgical scissors according to claim 23, wherein: said cobalt base alloy contains at least about 50% by weight cobalt.

Claim 29

A surgical scissors according to claim 23, wherein: said cobalt base alloy contains about 20 to 30% by weight chromium, and said cobalt base alloy contains at least about 38% by weight cobalt.

Claim 30

A surgical scissors according to claim 26, wherein: said cobalt base alloy contains about 0.45 to 0.55% by weight carbon.

Claim 31

A surgical scissors according to claim 27, wherein: said cobalt base alloy consists essentially of, in weight percent, about 25-29% Cr, 2-3% Fe, 5-6% Mo, up to 0.04P,, up to 0.007% B, up to 1% Ni, up to 1% Mn, up to 1% Bi, balance Co and trace amounts of incidental impurities.

Claim 32

A surgical scissors according to claim 28, wherein: said cobalt base alloy consists essentially of 28.6% Cr, 2.7% Fe, 5.3% Mo, 0.54% C, 0.25% Ni, 0.91% Bi, 0.5% Mn, less than 0.01% P, 0.005% S, 0.005% B, balance Co in an amount of at least 61.2%.