US 5,272,930 A · Mechanical element having a shaft pressure-fitted into an engaging member and its manufacturing method

Abstract

A mechanical element has a shaft pressure-fitted into at least one composite engaging member. The shaft has at least one engaging region disposed thereon, and at least one swollen portion formed radially outwardly around the engaging portion. The composite engaging member comprises an engaging body made of sintered alloy and having a recess therein, and a ring-shaped steel inner piece having a hardness not greater than the swollen portion. The inner piece is secured to the inside circumference of the recess of the engaging body by a securing method. The inner piece has a shaft hole formed therein, the shaft hole having a plurality of a larger inside diameter portions and a plurality of a smaller inside diameter portions arranged circumferentially, with the smaller inside diameter arranged to be smaller than the outside diameter of the swollen portion of the shaft. The composite engaging member is then pressure-fitted onto the shaft mainly in a plastic-deforming operation, with a minor chip-removing operation, if any, between the swollen portion and the shaft hole, to form the mechanical element.

Claims16

Dependent claims

A mechanical element having a shaft pressure-fitted into at least one composite engaging member comprising:

said shaft having at least one engaging region disposed thereon, the shaft having at least one swollen portion formed radially outwardly around said engaging portion;
said composite engaging member including an engaging body made of sintered alloy, said engaging body having a recess disposed therein and having a minimum radial width;
said engaging body having a ring-shaped steel inner piece secured to the inside circumference of said recess of said engaging body by a securing method, the inner piece having a maximum radial width, said inner piece having a hardness not greater than said swollen portion, the minimum radial width of the engaging body being greater than the maximum radial width of the inner piece such that the inner piece is markedly smaller in radial width than said engaging body, the inner piece being generally circular around an outer circumference thereof, said inner piece having a shaft hole formed axially therein, said shaft hole having a plurality of larger inside diameter portions and a plurality of smaller inside diameter portions, said smaller inside diameters being smaller than an outside diameter of said swollen portion;
said composite engaging member being fitted on said shaft by being pressure-fitted onto said shaft and having at least plastic deformation between said swollen portion and said shaft hole.

1 more element

A method for manufacturing a mechanical element having a shaft pressure-fitted into at least one composite engaging member, said shaft having an engaging region disposed thereon, said composite engaging member comprising an engaging body and a ring-shaped inner piece having a generally circular outer circumference, the engaging body being a sintered alloy and having a recess therein, the engaging body having a minimum radial width, the method comprising the steps of:

forming a swollen portion radially outwardly around said engaging portion of said shaft;
forming said composite engaging member by securing said generally circular outer circumference of said inner piece to an inside circumference of said recess of said engaging body by a securing method, said inner piece having a hardness not greater than said swollen portion and having a maximum radial width, the minimum radial width of the engaging body being greater than the maximum radial width of the inner piece such that the inner piece is markedly smaller in radial width than said engaging body;
forming a shaft hole axially in said inner piece, said shaft hole having a plurality of larger inside diameter portions and a plurality of smaller inside diameter portions, said smaller inside diameter portions being smaller than an outside diameter of said swollen portion;
and
pressure-fitting said shaft into said composite engaging member and causing at least plastic deformation between said swollen portion and said shaft hole.

2 more elements

Dependencies are inferred from the claim text.

Mechanical element having a shaft pressure-fitted into an engaging member and its manufacturing method

Life of this patent

Mechanical element having a shaft pressure-fitted into an engaging member and its manufacturing method

Life of this patent

Abstract

Claims16