PISTON FOR CLUTCHING AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a piston for clutching having an outer cylindrical part with a large wall thickness embodied without executing any machining process or bonderizing treatment. SOLUTION: The piston 1 for clutching is composed of a piston body 2 in a ring shape, an outer cylindrical part 3 tying to the peripheral edge of the piston body 2, and an inner cylindrical part tying to the inner edge of the piston body 2 and concentrical with the outer cylindrical part 3. The outer cylindrical part 3 is composed of a riser part 3a tying to the peripheral edge of the piston body 2 and rising in the axial direction of the piston body 2 and a foldback part 3b tying to the forefront of the riser part 3a and folded back in such a way as covering the peripheral surface of the riser part 3a.