Patent GB-141319-A (GB)
Title: Method of and devices for welding buckles, chain links, rings and the like
IPC: B21L3/02
Filed: 1919-10-22
Abstract: 141,319. Bindel, F. W. Oct. 22, 1919. Chains; fastenings; rings.- In welding buckles, chain links, rings &c. by dies which move endways at each side of the blank, the dies are at first given in addition a transverse movement so as to shape the blank and thus prevent the formation of fins when the weld is completed by the dies moving endways cnly. The necessity of using blanks of the exact shape of the cavity in the dies is thus avoided. As shown in Figs. 4 to 6, inclined surfaces e, f on the dies a, c cause, in the initial stages of the operation, relative transverse movement when end pressure is applied and the blank is thus pressed by the projection d on the die c into the recess b in the die a. In the form shown in Fig. 13, the dies are pressed by springs i, j, against parallel guide-surfaces k, l, so as to be situated in parallel planes, inclined surfaces m, n allowing transverse movement of the dies. A series of pairs of dies may be used so as to complete the form in stages, alternate pairs of dies being reversely arranged. In some cases, one die only need by yieldingly mounted. The dies. may be operated by hand. In the form shown in Figs. 16 and 18, the blanks are presented to the machine in U-form and the ends, which are preferably pointed or reduced, are bent and then welded by a series of pairs of dies mounted in a two-part turret 1, 2, which is rotated step by step by a ratchet-wheel 7, pawl 6, lever 8, and connecting-rod 9 and held in position by a brake 40. Bending is effected by concave tools 37, 38.. rotated in opposite directions round a mandrel 36, the parts being carried by slides 33, 34 mounted on the turret. The slides are operated against the action of springs by members 57, 58 reciprocated by rods 59 and cranks 60 from a shaft 48, the ends of the members engaging screws 61, 62, Fig. 18, secured in nuts 65. 66 keyed to the slides and pressed outwards by springs 67, 68. When the stops 63, 64 engage the ends of the turret, the nuts 65, 66 are pushed forward and rotate the screw spindles 69, 70 carrying the tools, cams 75 on the screws pressing spring-retracted stops 78 into recesses 76 in the turret. Inclined surfaces 73, 74 on the spindles withdraw the spindles so as to allow the tools to pass over one another. The slides are withdrawn by members 77, the nuts 65, 66 first rotating the spindles backwards so as to withdraw the stops 78. The pairs of welding dies 18, 19, 20, 21, 22, 23, 24, 25 are moved in turn by rams 41, 42 connected by links, advanced by wooden springs or cushions and retracted by a cam 49 engaging a slot in the ram 42, the rams being normally held back by projections 44, 45 on the turret. The cam is shaped to give two successive strokes to the rams. Projections on the rams engage projections on the dies for withdrawal purposes. The links are held in a fixed position throughout the operations by means such as a pair of pliers secured to a stationary support. In the Specification as open to inspection under Sect. 91 (3) (a) it is stated that the dies a, c may be used at an angle to one another, the directions of main pressure being co-planar when the dies are closed together. This subject-matter does not appear in the Specification as accepted.