Material combinations and processing methods for a surgical instrument

Patent metadata

Field	Value
Publication number	US-12357304-B2
Application number	US-202418756597-A
Country	US
Kind code	B2
Filing date	Jun 27, 2024
Priority date	Oct 29, 2020
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

Surface preparation for sliding surfaces can enhance wear performance for surgical instruments such as surgical staplers which include reusable mechanisms that are used multiple times with single use reload cartridges. To reduce the potential for galling wear in a metal-to-metal sliding engagement, a combination of surface hardening, surface finish, and surface coatings can be applied to metallic components of a surgical instrument. Surface hardening techniques can allow further manufacturing operations such as welding without compromising the strength of the underlying metal substrate. With stainless steel metal substrates, as surface or case hardening techniques can reduce corrosion resistance, a surface coating can be applied to inhibit surface oxidation as well as provide a barrier to metal-to-metal contact. A further lubricious coating layer such as a bone wax coating layer can enhance galling resistance.

First claim

What is claimed is:

1. A surgical instrument comprising:
an end effector comprising:
a first jaw comprising a first channel formed therein, and
a second jaw pivotably coupled to the first jaw, the second jaw comprising

a second channel formed therein; and
a firing member longitudinally slidably engaged with the end effector to pivotably move the second jaw with respect to the first jaw and actuate the end effector, the firing member having an I-beam profile defined by an upper flange connected to a lower flange by a vertical blade member, the upper flange being slidable within the first channel and the lower flange being slidable within the second channel;
wherein at least a portion of each of the first jaw, the second jaw, and the firing member that are in sliding engagement comprises a sliding surface configured to resist galling, the sliding surfaces each comprising a metallic substrate layer, a metallic surface layer, a first surface coating layer overlying the metallic surface layer, and a second surface coating layer overlying the first surface coating layer.

2. The surgical instrument of claim 1 , wherein the metallic substrate layer has a first hardness and the metallic surface layer has a second hardness greater than the first hardness.

3. The surgical instrument of claim 2 , wherein the hardness of the metallic surface layer is within the range of approximately 45 HRC to approximately 70 HRC.

4. The surgical instrument of claim 2 , wherein the metallic surface layer comprises a case hardened surface.

5. The surgical instrument of claim 1 , wherein the first surface coating layer comprises an oxidation inhibition material.

6. The surgical instrument of claim 1 , wherein the first surface coating layer comprises a dry film PTFE coating.

7. The surgical instrument of claim 1 , wherein the second surface coating layer comprises a lubricant material.

8. The surgical instrument of claim 7 , wherein the second surface coating layer comprises a bone wax layer.

9. A surgical stapler comprising:
a jaw assembly comprising:
an anvil comprising a first channel formed therein, and
a reload support coupled to the anvil, the reload support comprising a second channel formed therein; and

a firing member longitudinally slidably engaged with the jaw assembly to pivotably move the anvil with respect to the reload support and actuate the jaw assembly, the firing member having an I-beam profile defined by an upper flange connected to a lower flange by a vertical blade member, the upper flange being slidable within the first channel and the lower flange being slidable within the second channel;
wherein the anvil, the reload support, and the firing member each comprise sliding surfaces defined by a metallic surface layer, a first surface coating layer overlying the metallic surface layer, and a second surface coating layer overlying the first surface coating layer, and
wherein the metallic surface layer of the sliding surface of the anvil and the reload support has a first hardness, wherein the metallic surface layer of the sliding surface of the firing member has a second hardness, and wherein the second hardness is lower than the first hardness.

10. The surgical stapler of claim 9 , wherein the first hardness and the second hardness are within the range of approximately 45 HRC to approximately 70 HRC.

11. The surgical stapler of claim 10 , wherein the second hardness is up to approximately 10 HRC smaller than the first hardness.

12. The surgical stapler of claim 9 , wherein the first surface coating layer comprises a dry film surface coating.

13. The surgical stapler of claim 9 , wherein the second surface coating layer comprises a bone wax layer.

Assignees

• Applied Med Resources

Inventors

• Krasts Andrew
• Darnall Darci
• Weiss Eric J
• Hopkins Timothy M

Classifications

• A61B2017/00933

  bone or bone-like · CPC title

• A61B2017/00845

  of moving parts with respect to each other · CPC title

• A61B2017/00836

  corrosion-resistant (A61B2017/00853 takes precedence; preventing galvanic or electrolytic corrosion in prostheses A61F2210/0009) · CPC title

• A61B2017/00526

  Methods of manufacturing · CPC title

• A61B2017/07214

  Stapler heads · CPC title