GB213902A - Improvements in lock nuts - Google Patents

Abstract

213,902. Furlan Nut Machinery Corporation, (Assignees of Furlan, J. G.). April 2, 1923, [Convention date]. Turning.-In a method of producing lock-nuts of the kind wherein two groups of threads are in axial alignment but are displaced axially out of helical alignment the thread is separated by an annular groove into two sections and lateral pressure is applied to the groove to displace one section axially relatively to the other. As applied to a turret lathe, Fig. 1, bar stock 4 from which nuts are produced is fed against a stop 6, after which a drill 7 and a tap 8 are brought into operation. The groove 11, which has inclined sides, Fig. 4, is then acted upon by an expanding tool 9 which consists of rollers 10, Fig. 2, carried by levers 15 and pressed into engagement with the work by a wedge 12 introduced between adjustable screws 14. The wedge is carried by a cross-slide 13, Fig. 1, which also carries a forming tool 16 so that when one nut is being expanded the next nut is being grooved and chamfered. Finally a tool 18 cuts off the expanded nut. The rollers 10 engage the inclined sides of the groove 11 and deform these axially to the shape shown in Fig. 5 so that the diameter of the thread remains unchanged. The groove 11 may be cut before or after screwing and the steps of the method may be performed independently. Tools.-The Specification as open to inspection under Sect. 91 (3) (a) comprises also a similar method of making lock-bolts. Fig. 13 (Cancelled), the sequence of operations being similar but the grooves 11 being produced by the form-tools shown in Figs. 8 (Cancelled) and 12 (Cancelled) and the rollers acting on the bottoms of these grooves. This subject-matter does not appear in the Specification as accepted.