My invention further comprises a modification of the above described process, which has for its object to enable the weldless stayed links to be made as short and particularly as narrow as may be necessary in order to adapt the chain to run over the sheaves of pulley blocks and to suit other purposes for which short-link welded chain has heretofore only been available.
[Illustration: Figures 5_a-c_, 8_a_, 9_a_, 10-12
MANUFACTURE OF WELDLESS CHAINS.]
In the manufacture of chains by the aforesaid process of punching there is a practical minimum limit for the dimensions of the punches which cannot be reduced without compromising their efficiency, and consequently the width (and therefore the length) of the link must necessarily bear a certain proportion to the thickness of the web of metal out of which it is formed, since the breadth of the link depends on the length of the cross stay, which is determined by the breadth of the mortises forming the eyes of the link. The present modification enables these dimensions to be reduced without reducing the dimensions, and consequently the efficiency, of the punches which form the eyes of the link. The modification applies to what I have designated the fifth operation of the above described process; and it consists in punching out the middle of the cross stay (so as to leave only two short stumps jutting inward from the side members of the link), this operation serving to interrupt the continuity of the core, which was the object of the fifth operation. For this purpose I substitute for the pair of punches illustrated in Figs. 5_a_ and 5_c_ a single punch, which removes that part of the “core” of the cruciform bar which is situated at the middle of the strut. This tool is represented in Fig. 11, and the effect of its operation is shown in Fig. 12. The subsequent operations, herein designated the sixth, seventh, eighth, and ninth operations, are performed as hereinbefore described; but the tenth operation has the effect of closing together the two stumps, g g, until they abut together at the middle of the link and together constitute a cross strut or stay, which prevents any further lateral collapse of the link. In the operation of closing up the gap between the stumps, g g, the link is brought to the narrow form shown in Fig. 12, the eyes of the links being only just wide enough to receive the end of the adjacent link enchained therewith without gripping it. This operation is performed by a tool similar to that shown in Figs. 10_a_ and 10_b_, above referred to.
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