GB518168A - New or improved means for controlling undesired movement of a vehicle - Google Patents

Abstract

518,168. Preventing reverse movement of vehicle and other shafts. HACKETT, , A. G., and EDWARDS, J. L. July 18, 1938, No. 21210. [Class 103 (i)] [Also in Group XXIV] For ensuring unidirectional rotation of the shaft of a vehicle, crane &c., part-circular detents 12 are mounted to turn in recesses ina fixed member 10, to engage a toothed disc 11 on the shaft. The tooth faces engaged by the detents are preferably concentric with the detents to facilitate disengagement when required. As applied to the end of the wormshaft 27 of a vehicle rear-axle drive to prevent reverse movement of the vehicle, detents 29 mounted in a fixed casing 28 to engage a toothed disc 25 on the shaft are held in neutral position during forward running of the shaft by a cam ring 33 frictionally engaged with the shaft, the periphery of which engages parts 30 of the detents. Turning movement of the ring 33 is. limited by a stop 38<1>. When the shaft tends to reverse, recesses 37 in the ring 33 permit springs 32 to turn the detents into the engaged position. The cam ring may be held in neutral position, to permit reverse movement of vehicle, by engagement of a lug 40 on the ring with a finger 41 on a spindle having an arm 43 which may be connected to a hand- 'lever or to the, gear-selecting mechanism. According to Fig. 11, a vertical hand-lever l controlling the detent device is mounted adjacent the gate of the change-speed mechanism and normally occupies the position 601. When the gear lever is moved in the slot shown to the reverse position R it engages a peg 63 on lever l and moves this lever to position 60<11> in which the detent is held out of action and in which it is held by a latch 65 until when the gear lever is moved to the other end of the slot to engage a forward gear, it engages a finger 67 which releases the latch and permits return of the lever l. In another arrangement a lever mounted on the gear box is adapted to be moved to hold the detent out of action by the selector rod which engages the reverse gear and to be held in this position by a latch which is disengaged by the selector rods for engaging the forward gears. The detents may instead be controlled directly by a hand-lever or in the case of a trailer vehicle by breakage of the coupling, by a spring-urged cam ring' which puts the detents into engagement when a latch is withdrawn by a cable extending to the tractor.