Method for installing end member to hollow shaft member

A method for attaching an end member (20) to the end of a hollow shaft member (10), comprising the steps of:

• (1) providing a cylindrical hollow shaft member (10) made of soft metal and having an inner wall surface formed at an inside diameter about an axis thereof and having an outer circumferential surface;
• (2) providing a cylindrical end member (20) made of hard metal and having an outer circumferential surface formed at an outside diameter about an axis thereof such that a substantially coaxial relationship occurs when the end member (20) is inserted into an end of the hollow shaft member (10), said end member (20) having a first circumferential groove (21) and at least a second circumferential groove (21′) formed therein at predetermined respective distances from an end of the end member (20), the first groove (21) and the second groove (21′) having respective bottom surfaces substantially coaxial with the axis of the end member (20);
• (3) inserting the end member (20) into the end of the shaft member (10) a sufficient, distance so that the first groove (21) and the second groove (21′) are within the end of the hollow shaft member (10);
• (4) constraining the outer circumferential surface of the hollow shaft member (10) in a close fitting circular die to prevent expansion thereof in an outward direction;
• and
• (5) pressing at least three circumferentially spaced portions of the hollow shaft member (10) into the first groove (21) of the end member (20) using at least three respective rod-type pressing members (39a,39b,39c) and into the second groove (21′) of the end member (20) using at least three other respective rod-type pressing members (39′a,39′b,39′c) so that at least three circumferentially spaced portions of the hollow shaft member (10) are forcibly pressed into engagement with the bottom surface of the first groove (21) and at least three other circumferentially spaced portions of the hollow shaft member (10) are forcibly pressed into engagement with the bottom surface of the second groove (21′) to thereby attach the end member (20) to the end of the hollow shaft member (10), the three circumferentially spaced portions of the hollow shaft member forcibly pressed into engagement with the bottom surface of the first groove (21) being circumferentially separated from one another and the three circumferentially spaced portions of the hollow shaft member forcibly pressed into engagement with the bottom surface of the second groove (21′) being circumferentially separated from one another.