To provide a high fatigue strength type wheel disk having excellent fatigue strength, a forming die, a working method and a fitting method.
The wheel disk 1 for a passenger car having excellent fatigue strength has a plurality of contact surfaces 3 with a vehicle hub 4 in the circumferential direction. The wheel disk is formed of a steel plate of the tensile strength of 590 MPa, and at least one recess 2 having deapth less than 50 m, the minor diameter of a planar shape of 2-10 mm, and the major diameter of 3-20 mm with the ratio of the major diameter to the minor diameter being 1-8 at the center of each contact surfaces 3. The wheel disk has at least one projection of the height of 100 m, the minor diameter in plan view of 2-10 mm, and the major diameter of 3-20 mm with the ratio of the major diameter to the minor diameter being 1-8 on the surface having the contact surfaces 3 with the vehicle hub 4.
Tetsuo Kanamoto
Miaki Kametani
Next Patent: ASSEMBLY OF VEHICULAR STEERING COLUMN