JPS561217A - Manufacturing apparatus for metal made polygonal cylinder - Google Patents

Abstract

PURPOSE: To press and bend the sheet blank into a polygonal cylinder, and to make mass production of the titled product of high accuracy and uniform shape possible through two passes, by making a V-notch at the bending position of the metallic blank to be formed into the polygonal cylinder, and by using the core die and the pinch die possessing the ridgeline coincident with the V-notch.

CONSTITUTION: The uniformly pitched V-notches 16 are made in one side of the metallic sheet blank 13 by the male die 11 and the female die 12 possessing the cavity 14. The depth (t) of notches 16 is desirable to be t=T/2WT/4, for example, in which T is for thickness of the blank 13. Next, the blank 13 is laid across the poles 27, 27, and the press die 17 is put down for pushing down the middle of the blank 13 by its core die 18, and hereby, the blank 13 is pushed into the gap between the pinch dies 21, 22. Hereby, the blank 13 is bent so as to wind around the core die 18. At this bending work, the blank 13 is bent along the V-notch by the coinciding action of the octagonal ridgeline of the core die 18 with the V-notch. Further, the core die 18 pushes down the back side of the pinch die so as to make both pinch dies to close; thus the blank 13 is wound around the core die 18, and the blank 18 is bent to form the octagonal cylinder.

COPYRIGHT: (C)1981,JPO&Japio