US 4,543,857 AGranted

Surgical instrument and method of making same

AssigneeUrban Engineering Company, Inc.

InventorsLarry K. Kleinberg, Don S. Evans

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Abstract

A surgical instrument, with method and apparata for making same. A pair of coaxial tubular members include cooperating oval openings the formations of which are developed by the apparata and method. One apparatus comprises a fixture for supporting the inner or blade member in a spindle having a follower, and a cam assembly and registry means for mounting to the fixture. The cam assembly is mounted to the fixture and through cooperative action with the follower directs movement of blade member and spindle during grinding formation of a blade's thickness including a positive cutting angle across its wall. The registry means comprises a body mountable to the cam assembly and having a pin which properly seats an initially formed opening in the blade member exteriorly of the cam assembly for subsequent grinding thereon. A second apparatus provides for the initial formation of both openings after which the first apparatus operates to finish the blade member's body formation for its opening. The methods of forming these openings also are unique.

Claims19

Dependent claims

A method of forming a positive cutting angle across the thickness of a tubular wall forming a cutting edge about a compound oval opening in a tubular member having such wall and comprising the steps of

(1) securing a fixture including a bore terminating at an end face for the fixture,
(2) inserting into the fixture's bore a cylindrical unit comprising a spindle and a tubular member with such an opening in its tubular wall, at least the opening projecting outwardly of the fixture's face and having on the spindle a follower extending therefrom in an angular direction,
(3) positioning a camming surface relative to such follower for cooperative engagement during subsequent grinding action on the cutting edge,
(4) engaging the spindle's follower with the camming surface,
(5) securing the spindle to the fixture,
(6) setting the extent of the projection of the tubular member's compound oval opening,
(7) registering the cutting edge about such opening in a proper position for subsequent grinding action thereon,
(8) securing the tubular member to the spindle,
(9) unsecuring the cylindrical unit from the fixture, and
(10) causing the follower to follow the camming surface during grinding action on the cutting edge forming the compound oval opening.

7 more elements

Dependencies are inferred from the claim text.