GB209191A - Improvements in the manufacture of cams and camshafts - Google Patents

Abstract

209,191. Soc. Anon. des Anciens Etablissements Hotchkiss et Cie, and Taylor, H. E. Oct. 5, 1922. Shaping; tools.-Cam shafts, e.g. for internal-combustion engines, are machined by a series of planing-tools which are controlled by a master cam shaft rotating in phase with the work, the cutting action of the tools being in a direction parallel with the work axis. The work E, Fig. 1, is mounted by means of a chuck L and a swivel bearing L' in a vertical slide J which is reciprocated by a crank-shaft driven through gearing from the main shaft of the machine. The planing-tools C<2>, one for each cam, are carried by holders formed with slots in which operates the cams D<2> of the master cam shaft D. The holders are held up to their operating cams either by springs or by a system of interacting levers Q, Q<3>, Q<4>, acted on by a cranked lever and a hanging weight. The master carn shaft and the work are rotated synchronously by worm gearing M, O<2>, splined shafts being provided as necessary. The master cam shaft is carried in eccentric bearings P, P<2> which are yoked together and are partially rotated at each reciprocation of the elide J in order to lift the tools clear of the work during the idle stroke. The depth of cut is determined by a cam F actuating a rod G' having a threaded portion G<4> connected by means of a nut G<5> to the slide B on which the master cam shaft and the cutting tools are mounted. The nut G<5> may be rotated by a handle to adjust the slide B independently of the feed cam F. The master cams are made larger than the work shaft cams but have the same lift and angular pattern. The machine is started bv a handle S and a handle T may be provided to throw the feed cam in or out of gear. The machine may be stopped by an automatic mechanism operated by the feed cam. In a modification, the tools may be secured in levers which are rocked by the cams of the master cam shaft.