Anvil for circular surgical stapler and associated method of manufacture with MIM

Patent metadata

Field	Value
Publication number	US-12023032-B2
Application number	US-202117155799-A
Country	US
Kind code	B2
Filing date	Jan 22, 2021
Priority date	Dec 31, 2018
Publication date	Jul 2, 2024
Grant date	Jul 2, 2024

Abstract

A method is used to manufacture an anvil of a surgical circular stapler. The anvil includes a head and a shank extending proximally from the head. The method includes forming the head of a surgical circular stapler using a metal injection molding process. The method also includes forming an annular array of staple forming pockets in the head. The method also includes machining the shank of the surgical circular stapler. The method also includes coupling together the head and the shank of the surgical circular stapler that were separately manufactured.

First claim

We claim:

1. A surgical instrument comprising:
(a) a shaft extending distally;
(b) a stapling assembly operatively coupled with the shaft, wherein the stapling assembly includes:
(i) an anvil coupling projection,
(ii) at least one annular array of staples, and
(iii) a staple driver; and

(c) an anvil configured to couple with the anvil coupling projection, wherein the anvil is further configured to deform the staples driven by the staple driver, wherein the anvil comprises:
(i) a shank having a free distal end,
(ii) a head that includes an annular array of staple forming pockets, and
(iii) a cap coupling the shank and the head of the anvil together, wherein the cap defines a distal-most end of the anvil and includes a proximal end that overlies and directly contacts each of the free distal end of the shank and a distal end of the head to thereby fix the head relative to the shank, wherein the cap extends laterally across a distal end surface of the head to an outer-most edge of the distal end surface.

2. The surgical instrument of claim 1 , wherein the cap is configured to sandwich a portion of the shank between the cap and the head.

3. The surgical instrument of claim 1 , wherein the cap is overmolded onto the shank and the head of the anvil.

4. The surgical instrument of claim 1 , wherein the cap includes at least one proximally facing projection, wherein the head includes at least one recess, wherein the at least one proximally facing projection is configured to be inserted into the at least one recess to secure the cap to the shank.

5. The surgical instrument of claim 1 , wherein only a predetermined surface of at least one staple forming pocket of the annular array of staple forming pockets has a smoother and denser surface than a remaining surface of the staple forming pocket that is less dense than the predetermined surface.

6. The surgical instrument of claim 1 , wherein the free distal end of the shank includes a flange extending radially outward, wherein the cap is configured to sandwich the flange of the shank between the cap and the head.

7. The surgical instrument of claim 6 , wherein the cap is fixably coupled with at least one of the flange of the shank or the head.

8. The surgical instrument of claim 6 , wherein the head comprises a distal outer surface and a distal recessed portion that is disposed proximal to the distal outer surface, wherein the distal recessed portion is sized and configured to receive the flange of the shank.

9. The surgical instrument of claim 8 , wherein the flange includes a proximal surface that is opposed from the distal surface, wherein the proximal surface of the flange is configured to contact the distal recessed portion of the head.

10. The surgical instrument of claim 9 , wherein the cap is coupled with the distal surface of the flange and the distal outer surface of the head.

11. The surgical instrument of claim 9 , wherein the proximal surface of the flange is configured to contact the distal recessed portion of the head such that the distal outer surface of the head is generally flush with the distal surface of the flange.

12. The surgical instrument of claim 6 , wherein the flange includes an inner shallow portion and a rounded outer edge portion, wherein a proximal surface of the flange is coupled with a distal surface of the head.

13. The surgical instrument of claim 1 , wherein the head is formed from a metallic material, wherein the shank is formed from a metallic material, and wherein the cap is formed from a polymeric material.

14. A surgical instrument comprising:
(a) a shaft extending distally;
(b) a stapling assembly positioned at a distal end of the shaft, wherein the stapling assembly includes:
(i) an anvil coupling feature,
(ii) at least one annular array of staples, and
(iii) a staple driver, wherein the staple driver is operable to drive the at least one annular array of staples; and

(c) an anvil configured to couple with the anvil coupling feature, wherein the anvil is further configured to deform the staples driven by the staple driver, wherein the anvil comprises:
(i) a shank that includes a flange and defines an axial direction,
(ii) a head that includes an annular array of staple forming pockets, wherein a distal surface of the flange is flush with a distal surface of the head, and
(iii) a cap sandwiching the flange of the shank between the cap and the head of the anvil in the axial direction, wherein the cap is positioned distal to the distal surfaces of the head and the shank and is configured to couple the head to the shank.

15. The surgical instrument of claim 14 , wherein the cap is overmolded onto the flange of the shank and the head of the anvil to sandwich the flange of the shank between the cap and the head of the anvil.

16. The surgical instrument of claim 14 , wherein the head is formed from a metallic material, and wherein the shank is formed from a metallic material, wherein the cap is formed from a polymeric material.

17. A method of manufacturing an anvil of a surgical circular stapler, wherein the anvil includes a head and a shank extending proximally from the head, the method comprising:
(a) manufacturing the head and the shank separately from one another;
(b) aligning the shank with the head such that a distal surface of the shank is flush with a distal surface of the head; and
(c) once the distal surface of the shank is flush with the distal surface of the head, coupling together the head and the shank of the anvil of the surgical circular stapler using at least one overmolding process.

18. The method of claim 17 , wherein the shank includes a flange, wherein the overmolding process further comprises overmolding a cap onto at least one the head or the shank to sandwich a flange of the shank between the cap and the head.

19. The method of claim 17 , wherein coupling together the head and the shank of the anvil further comprises overmolding the head directly to the shank of the anvil.

20. The method of claim 17 , wherein manufacturing the head and the shank separately from one another further comprises:
(a) forming the head using a metal injection molding process;
(b) forming an annular array of staple forming pockets in the head; and
(c) machining the shank of the surgical circular stapler.

Assignees

• Cilag Gmbh Int

Inventors

• Nalagatla Anil K
• Shelton Iv Frederick E
• Baxter Iii Chester O
• Gupta Amit
• Acharya Sambit Kumar

Classifications

• B21K5/00

  Making tools or tool parts, e.g. pliers · CPC title

• A61B2017/00734

  battery operated · CPC title

• A61B2017/00526

  Methods of manufacturing · CPC title

• A61B2017/00477

  Coupling (A61B2017/0046 takes precedence) · CPC title

• A61B2017/07257

  characterised by its anvil · CPC title