GB191403779A - Improvements in Feed Mechanism for Drilling Machines and the like. - Google Patents

Abstract

3779. Herbert, A., and Vernon, P. V. Feb. 13. Drilling-machines. - A feed-mechanism for drilling-machines of the type wherein the hand feed is automatically converted into a power feed on the tool coming into contact with the work, as described in Specification 16,704/13, has a positive clutch instead of a friction clutch, and may be provided with a stop-motion. The feed-sleeve A is fed by the usual rack-and-pinion motion from a feed-shaft A<4>, which carries a lever B, Fig. 2, mounted in a hole in the shaft so as to be capable of slight relative rotation. The lever has two V-projections B<2> adapted normally to engage two V-slots on the end of a clutch sleeve E, which carries teeth atits other end for engagement with corresponding teeth on a power-driven worm D, a spring E2 normally keeping the clutch out of gear. The feed-shaft is rotated by the lever B until the tool comes against the work, and the lever, on further rotation, rides out of the V-grooves and pushes the clutch into engagement, whereupon power feed occurs. If hand feed only is required, a cap-piece. J is used, having two projections J<2> which engage recesses G, Fig. 2, and prevent the. relative rotation of the lever B. To stop the feed, a head L, through which the lever passes, carries an adjustable ring M, which has a nose M2 adapted to engage a fixed stop N, whereby the lever B is stopped while the clutchpiece E still rotates until disengaged by the spring. The spindle head is retracted by means of a spring K, which is wound up during feeding.