| 摘要 |
732,600. Making dowel and like pins. STANDARD PRESSED-STEEL CO. April 20,1953 [Sept. 27, 1952], No. 10777/53. Classes 83 (2) and 83 (4). Stamping; breaking.-In a method of making slit tubular pins with bevelled ends in a connected strip for subsequent separation by breaking a strip 18, Figs. 7, 8, preformed to arcuate cross-section at its edges 13<SP>1</SP>, 14<SP>1</SP> as by rolls or dies is provided with transverse breaking grooves 17 by a punch 20, Fig. 6, before the strip is finally formed to circular section. The punch 20 has bevelled faces 23, 23<SP>1</SP> which form the bevelled ends and both the punch 20 and backing member 30 have arcuate contours corresponding to the cross-section of the blank 18. In making pins which are bevelled at one end only a section of the punch 20 is used with one of the bevelled faces removed. The finished connected strip is fed through a support 33, Fig. 10, engaged by an impact member 32 so that it breaks at the grooves 17. |
