| 摘要 |
PURPOSE:To save machining process and shorten the time for processing by forming the bearing accommodation part of an inner cylinder by means of press processing, and forming a bearing retaining pawl adjoining to this accommodation part in a small wall thickness by the same press processing. CONSTITUTION:In inner cylinder material 11 is fitted on a stepped punch 15 from above, and a pad 16 is put in contact with a dia. reduction end wall 14 and sunk to allow the inner cylinder material 11 to be intruded together with the punch 15 into a die 17. Now molding takes place. In this intruding process from a point near the finish till the very finish, the bottom of the inner cylinder material 11 is subjected to squeezing in cooperation of punch 15 and die 17 to accomplish small wall thickness. Thus a bearing retaining pawl 18 is formed through a series of press shaping works, wherein no machining process for making wall thickness smaller is required, and the operating time can be shortened and the cost suppressed. |
