| 摘要 |
PURPOSE:To form a fitted surface having high accuracy by means of press- working, by providing a specific projecting part on a cylindrical fitted surface, and after that, working the fitted surface by a ironing die, when deep drawing a steel plate and forming the cylindrical fitted surface. CONSTITUTION:When deep drawing a steel plate and forming a cylindrical fitted surface, at first, as the first process, a steel plate 11 is placed on a punch 12 having a lot of projecting parts 12a on its outside circumferential part, is pressed by a die 15, an excess metal is put out to an escape groove between the projecting parts 12a of the punch 12, and a projection 11a is formed on the inside surface of a work 11 of a formed steel plate. This work 11 is taken out and is inserted into a punch of a ironing die, and when the work 11 is pressed by a die and the projection 11a formed in the previous process is ironed, since a dent part in which an excess metal can be left is formed against the projection 11a in the work 11, the ironing excess metal is crushed and is plastically moved to the dent part, a variation of thickness of a metal in the first process is equalized, and a fitted surface having extremely high accuracy is formed on the inside surface of the work 11. |
