| 摘要 |
A wheel bearing spindle is produced by an improved method which provides adequate structural clearance from the sharp edge of a wheel drum hub, while actually improving the effective yield strength of the spindle. The spindle is produced from a near net shape steel forging which has a cylindrical spindle and flat wheel flange radiating therefrom. The circular hub of a brake drum fits radially closely over the pilot, and abuts with the wheel flange. Therefore, the juncture of the pilot and flange needs to be relieved or cut away somehow, both radially and axially, in order to assure non interference with the circular edge of the hub, which could prevent the rest of the hub from intimately abutting the surface of the wheel flange. The radial component of the clearance is provided by conventionally machining a channel radially into the pilot. This can be done, since it does not weaken the flange. The axial clearance, which has to be provided into the surface of the flange, is provided not by machining, but by a coining operation. This creates an axial channel of a specific shape which not only provides clearance but which, by strain hardening the surface of the flange near its juncture with the pilot, shifts the stress zone radially inwardly. This actually effectively increases the yield strength of the flange, despite the axial thinning of the flange.
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