Injection molded anvils

• US 5,308,576 A
• Filed: 10/18/1991
• Issued: 05/03/1994
• Est. Priority Date: 10/18/1991
• Status: Expired due to Term

• Current Assignee: United States Surgical Corporation (Medtronic Plc)
• Original Assignee: United States Surgical Corporation (Medtronic Plc)
• Inventors: Bolanos, Henry, Green, David T.
• Primary Examiner(s): Walsh, Donald P.
• Assistant Examiner(s): Greaves, John N.
• Application Number:
  US07/779,071
• Time in Patent Office: 928 Days
• Field of Search: 29/182, 75/235, 75/243, 75/246, 75/251, 75/252, 227/19, 227/76, 227/176, 227/178, 227/180, 264/63, 419/2, 419/3, 419/8, 419/23, 419/38, 419/36, 419/41
• US Class Current: 419/38
• CPC Class Codes: A61B 17/07207 the staples being applied sequentially
• CPC Class Codes: A61B 2017/07214 Stapler heads
• CPC Class Codes: B22F 2998/00 Supplementary information concerning processes or compositions relating to powder metallurgy
• CPC Class Codes: B22F 3/22 for producing castings from a slip
• CPC Class Codes: B22F 3/225 by injection molding

Abstract

A method for making metal injection molded medical devices is disclosed. The method comprises melt blending, inject ion molding, and sintering a granulated hardenable metal feedstock.

Claims

1. A method for producing a metal injection molded medical device in the shape of a grasping member comprising:

a. melt blending a feedstock, comprising a hardenable metal with a thermoplastic binder material;

b. injection molding the feedstock in a mold configured and dimensioned to form a medical device;

c. removing a majority of the binder material; and

d. sintering the medical device.

2. A method according to claim 1, wherein the melt blending process is extrusion.

3. A method according to claim 1, wherein the binder is removed by a solvent.

4. A method according to claim 3, wherein the solvent is selected from the group consisting of chloroform, methylene chloride, acetone, xylene, DMF and DMSO.

5. A method according to claim 1, wherein the binder is removed by thermal means.

6. A method according to claim 5, wherein the thermal means comprises a vacuum oven heated from about 1000 to about 2500°

C.

7. A method according to claim 1, wherein the metal has an average particle size of up to about 10 microns.

10. A medical device produced by the method of claim 1 wherein the device is a grasping member.

8. A method for producing a metal injection molded medical device comprising:

a. melt blending a feedstock, comprising a hardenable metal with a thermoplastic binder material;

b. injection molding the feedstock in a mold configured and dimensioned to form a medical device;

c. removing a majority of the binder material; and

d. sintering the medical device is in the shape of a member selected from the group consisting of an anvil, an anvil having a blank surface, an anvil having pockets configured in the shape of a rectangle, and an anvil having pockets configured in the shape of a star.

9. A method according to claim 8, wherein the device has a major axis of about 7 inches.

11. A method according to claim 8, wherein said thermoplastic binder material further comprises a material selected from the group consisting of animal wax, china wax, wool wax, paraffin wax, and mixtures thereof.