GB765196A - Improvements in apparatus for making bolts - Google Patents

Abstract

765,196. Forging bolts. GUEST, KEEN & NETTLEFOLDS (MIDLANDS), Ltd., and ACTON BOLT, Ltd. Aug. 3, 1954 [July 31, 1953], No. 21232/53. Class 83 (4). A side - forging die assembly 19 for mounting on the reciprocating punch slide 16 of a boltheading machine, comprises a plurality of dies 20, Fig. 2, corresponding in number to the number of sides on the bolt head, said dies being arranged in sets, which sets are closed successively on to the periphery of the bolt head in response to the forward movement of the punch slide. Six dies 20, for forming hexagon heads, are mounted in collet formation in a punch holder 19. The dies are biased into their open position by springs and have projections 26 which co-operate with two sets of axially spaced cam surfaces 31 on the stationary die 15, whereby three alternate dies 20 are first closed by the outer cam surfaces 31 and the other three dies are then closed by the inner cam surfaces after the first set of dies have been opened. The cam surfaces 31 may be in the form of rollers. The heading machine, Fig. 1, has a cut-off station 12 where a blank is severed from a stock length and then. transferred to a first heading station 13 where a conical head is formed. The blank is then transferred by transfer fingers, to a second station 14 where it is formed into a preliminary hexagonal shape and it is then moved into alignment with the die 15 and pushed therein by shoulders 25 on the dies 20. A retractable plunger may be provided instead of the shoulders 25 to push the blank into the die 15. The blank is removed from the die 15 by an ejector which pushes the blank through the bore of punch holder 19 where it falls into a shoot leading to a pointing and thread-rolling station.