Surgical stapler with corrugated thermoplastic leaf spring

Patent metadata

Field	Value
Publication number	US-9265501-B2
Application number	US-201213604919-A
Country	US
Kind code	B2
Filing date	Sep 6, 2012
Priority date	Sep 6, 2012
Publication date	Feb 23, 2016
Grant date	Feb 23, 2016

Abstract

A surgical stapler can comprise: a housing having side walls an end wall, a front wall, and a upper side that define a channel; a trigger; and a thermoplastic leaf spring having a proximal end and a distal end, the leaf spring comprising a non-corrugated portion and a corrugated portion. The leaf spring is attached to the trigger at the proximal end. The leaf spring extends from the trigger, through the channel toward the upper side. In an embodiment, a method for using a surgical stapler can comprise: creating relative motion between a housing and a trigger of a surgical stapler by placing a load on the surgical stapler; contacting a surface of the trigger with a cartridge comprising staple pins; releasing a staple pin from the cartridge and folding ends of the staple pin; releasing the load; and biasing the housing and trigger apart with the thermoplastic leaf spring.

First claim

What is claimed is:

1. A surgical stapler comprising:
a housing having side walls an end wall, a front wall, and a upper side that define a channel;
a trigger;
a thermoplastic leaf spring having a proximal end and a distal end, the leaf spring comprising a non-corrugated portion and a corrugated portion, wherein the proximal end is located closer to a staple release area than the distal end;
wherein the leaf spring is attached to the trigger at the proximal end;
wherein the leaf spring extends from the trigger, through the channel toward the upper side; and
wherein at least one of
(i) a corrugation amplitude in the corrugated portion is dissipating amplitude or accumulating amplitude, from the proximal end to the distal end;
(ii) the thermoplastic leaf spring exhibits maximum Von Mises stress of no more than 51 MPa for a load of 85% of a stapler load; and
(iii) the corrugated portion has a corrugation amplitude h of 1.0 to 10 mm, an amplification constant k of 0.2 to 2.0, a corrugation angle φ of 75 to 15 degrees, and a number of corrugations of 2 to 24.

2. The surgical stapler of claim 1 , wherein the corrugated portion has a thickness that is different than the non-corrugated portion.

3. The surgical stapler of claim 1 , wherein a thickness ratio between the proximal end and the distal end is 20:19 to 2:1.

4. The surgical stapler of claim 1 , wherein the thermoplastic material is polybutylene terephthalate; acrylonitrile-butadiene-styrene; polycarbonate; acrylic-styrene-acrylonitrile; acrylonitrile-(ethylene-polypropylene diamine modified)-styrene; phenylene ether resins; polyamides; phenylene sulfide resins; polyvinyl chloride; high impact polystyrene; thermoplastic polyolefins; or a combination comprising at least one of the foregoing.

5. The surgical stapler of claim 1 , wherein the thermoplastic leaf spring has Poisson Ratio of 0.3 to 0.5.

6. The surgical stapler of claim 1 , wherein Young's modulus of the thermoplastic leaf spring is 0.1 to 70 GPa.

7. The surgical stapler of claim 1 , wherein a thickness at the proximal end and the distal end of the thermoplastic leaf spring is 0.5 and 10 mm.

8. The surgical stapler of claim 1 , wherein the thermoplastic leaf spring has a span (L) of 50 to 150 mm and a width (W) of 2 to 20 mm.

9. The surgical stapler of claim 1 , wherein the corrugated portion has a length (l) of 2 to 50 mm.

10. The surgical stapler of claim 1 , wherein the corrugation amplitude is dissipating amplitude or accumulating amplitude, from the proximal end to the distal end.

11. The surgical stapler of claim 1 , wherein the thermoplastic leaf spring exhibits maximum Von Mises stress of no more than 51 MPa for a load of 85% of a stapler load.

12. The surgical stapler of claim 11 , wherein the surgical stapler has fixed thickness form proximal end to distal end of 1.5 to 2.5 and exhibits maximum Von Mises stress of no more than 42 MPa for a load of less than or equal to 60%.

13. The surgical stapler of claim 1 , wherein the thermoplastic leaf spring has a 10% decrease in thickness from the proximal end to the distal end.

14. The surgical stapler of claim 1 , wherein the corrugation amplitude h is 1.0 to 10 mm, an amplification constant k is 0.2 to 2.0, a corrugation angle φ is 75 to 15 degrees, and a number of corrugations is 2 to 24.

15. The surgical stapler of claim 1 , wherein the thermoplastic leaf spring is configured to undergo 40 to 60 compression-release cycles without increase in maximum Von Mises stress for a load of 85% of a stapler load.

16. The surgical stapler of claim 1 , wherein the thermoplastic leaf spring is configured to undergo no less than 38 compression-release cycles without increase in maximum Von Mises stress for a load of 85% of a stapler load.

17. A surgical stapler comprising:
a housing having side walls an end wall, a front wall, and a upper side that define a channel;
a trigger;
a thermoplastic leaf spring having a proximal end and a distal end, the leaf spring comprising a non-corrugated portion and a corrugated portion, wherein the proximal end is located closer to a staple release area than the distal end;
wherein the leaf spring is attached to the trigger at the proximal end;
wherein the leaf spring extends from the trigger, through the channel toward the upper side;
wherein the corrugated portion begins at a distance (X 0 ) of 50% to 95% from the distal end based on a span (L) of the surgical stapler.

18. Method for using a surgical stapler, comprising:
creating relative motion between a housing and a trigger of a surgical stapler by placing a load on the surgical stapler;
contacting a surface of the trigger with a cartridge comprising staple pins;
releasing a staple pin from the cartridge and folding ends of the staple pin;
releasing the load; and
biasing the housing and trigger apart with a thermoplastic leaf spring having a proximal end and a distal end, the leaf spring comprising a non-corrugated portion and a corrugated portion, wherein the leaf spring is attached to the trigger at the proximal end, and wherein the leaf spring extends from the trigger, through a channel in the housing, and
wherein at least one of
(i) a corrugation amplitude in the corrugated portion is dissipating amplitude or accumulating amplitude, from the proximal end to the distal end;
(ii) the thermoplastic leaf spring exhibits maximum Von Mises stress of no more than 51 MPa for a load of 85% of a stapler load; and
(iii) the corrugated portion has a corrugation amplitude h of 1.0 to 10 mm, an amplification constant k of 0.2 to 2.0, a corrugation angle φ of 75 to 15 degrees, and a number of corrugations of 2 to 24.

Assignees

• Tiwari Anil
• Sabic Global Technologies Bv

Inventors

• Tiwari Anil

Classifications

• A61B17/10

  for applying or removing wound clamps {, e.g. containing only one clamp or staple (A61B17/076 takes precedence; containing multiple wound clamps A61B17/068)}; Wound clamp magazines · CPC title

• A61B2017/00955

  thermoplastic · CPC title

• A61B17/0684 Primary

  having a forming anvil staying above the tissue during stapling · CPC title