| 摘要 |
PROBLEM TO BE SOLVED: To reduce the amount of scrap of a metal plate and eliminate obstacles to the manufacturing of highly accurate products about the base stock for forming an annular disk such as a retaining plate in the clutch pack of an automatic transmission of an automobile and the method for forming the same, and a die. SOLUTION: The base stock 10 for forming the annular disk is press-punched from a metallic plate and made into an ellipse. Formation from the ellipse to the circle is performed by plastic working and the minor axial part is extended and the major axial part is reduced by bringing a forming part 27 contact with the inner periphery of the minor axial part of the base stock 10 and making the forming part 27 separate and move with a cam 22. Finally, the base stock is plastically deformed into the circle by guiding the base stock in the outer circumference by a recessed part 24-2 during working. Restriction is performed between the upper and lower surfaces so as to prevent the stock from running off during plastic deformation. COPYRIGHT: (C)2012,JPO&INPIT |
