GB511217A - Improvements in or relating to forged engine crankshafts and the manufacture thereof - Google Patents

Abstract

511,217. Forging crank shafts. CHILTON, R. April 22, 1938, No. 12103. Convention date, May 1, 1937. [Classes 83 (ii) and 83 (iv)] Dies.-Multiple throw crankshafts are made from tubular or other metal stock by means of clamps or dies, all of which move axially of the work and some of which move also laterally. This produces a shaft with the grain following the contour thereof. As shown, a metal tube or other stock is clamped in dies carried by bars 22 to 28, Fig. 6, corresponding to the number of journals, the die bar 28 being fixed, the die bars 23, 24, 26, 27, corresponding to the crank-pin journals, moving laterally as well as axially, and the die bars 22, 25 and 28, corresponding to the main journals, not moving laterally. A guide rod 31 is attached to the fixed die bar 28, which is itself attached to a fixed platen 21. The die bar 22 is attached to a moving platen 20. Linkage 34 connects the die bars as shown. The four throw crank shaft produced by this apparatus is shown in Fig. 13. In the production of a six throw crank shaft, with crank pin journals in pairs spaced 120 degrees apart, three banks of die bars are spaced 60 degrees apart. Fig. 1 shows the means for operating the clamping devices, piston rods 58 operated by pressure in cylinder 59, transmitting pressure by links 60, 61 shown in the dead centre lock position of a pivoted clamp element 56.