MANUFACTURING METHOD OF PISTON OF VEHICLE DISC BRAKE, SPINNING PROCESSOR OF PISTON OF VEHICLE DISC BRAKE AND PISTON OF VEHICLE DISC BRAKE

摘要

To provide a manufacturing method of a piston of a vehicle disc brake for forming a corner between an opening end-part side external peripheral end part and an opening end part into a desired R-shape by applying spinning processing by using a prescribed pressing roller without preparatorily forming a base material having a straight shape.SOLUTION: An annular groove 54 is formed by rotating a bottomed cylindrical base material 15. An opening end-part side external peripheral end part 20, an opening end part 19 and a corner 21 are formed by pressing, from the opening end part 19 and an external peripheral face 18, a groove forming roller 3 having a protrusive groove forming part 32 from the external peripheral face 18 of the base material 15, a corner forming roller 4 having an external peripheral end-part forming part 42 contacting with the opening end-part side external peripheral end part 20 of the base material 15, an opening end-part forming part 41 contacting with the opening end part 19 of the base material 15, and an R-shaped corner forming part 47 for forming the corner 21 between the opening end-part side external peripheral end part 20 and the opening end part 19.SELECTED DRAWING: Figure 1