GB652546A - A device for restraining return motion - Google Patents

Abstract

652,546. Ratchet gearing; locking devices. VITKOVICKE ZELEZARNY NARODNI PODNIK, and KOUN, M. Aug. 24, 1948, No. 22303. Convention date, Aug. 26, 1947. [Class 80(iii)] A housing 1, Fig. 3, slidable along a guide 4 (which may be a rod, cable, chain or the like), is restrained from return motion by wedging means comprising two or more cheeks 2, 3 normally spring-pressed into engagement with the guide. Balls or rollers 5 are interposed between the parallel wedging surfaces of the cheeks 2, 3 and the housing 1. Initial movement in the direction S<SP>2</SP> compresses springs 8 until motion is unrestrained. Initial movement in direction S<SP>1</SP> causes the cheeks 2, 3 firmly to clamp the guide 4, thus preventing motion in this direction unless a lever 9 is rotated to compress the springs 8 and release the cheeks. Two oppositely acting wedging devices may be contained in one housing, Fig. 4, so that the direction of locking may be changeable. either the bolts 19 or the bolts 19a being withdrawn and held by pins 20. The device may be used as ratchet means in an apparatus in which it is desired to convert reciprocating motion into step-by-step motion along a guide. In one application a drilling hammer is rigid with a restraining device according to Fig. 3 and is automatically advanced along a fixed guide by virtue of the reaction on the casing of the impact piston. In a second application a coal cutting machine carries two restraining devices, the one rigid with the machine to prevent backrunning and the other reciprocated by a motor carried by the machine. The amplitude of the reciprocation is adjusted by moving the pivot pin of an oscillating slotted lever.