GB205832A - Improvements in or relating to speedometers - Google Patents

Abstract

205,832. Suffit, R. Courtois-. Oct. 23, 1922, [Convention date]. Void [Published under Sect. 91 of the Act]. Impulse and momentum speed indicators.- The shaft or reciprocating member whose speed is to be measured drives a rotary member 4, Fig. 1, having teeth or a friction surface over part of its periphery engaging teeth or a friction surface of a wheel 1, which is advanced during the engagement of surfaces and returned during disengagement by a spring 2. Tappets 38, 39 on the wheel 1 engage a rod 40 on the index hand 3, which is mounted on an axis independent of and in alignment with the shaft of the wheel 1, and is retained by a blade spring 37 in a position corresponding with the mean position of the oscillating wheel. The wheel 1 may be returned by a spring-actuated sector 41, Fig. 8, the spring 42 of which, owing to its angular position, acts with increasing force as the speed increases; or a number of springs coming into action successively may be employed. The transmission shaft may be in alignment with the axis of the wheel 1, as shown in Fig. 9. In this arrangement the actuating pinion 4 is carried by an arm 43 on a driven shaft 7, and rolls freely on the wheel 1, except when an arm 46 on the pinion engages internal projections 45 on an enclosing ring 44, during which time the wheel 1 is advanced. The wheel 1 or the pinion 4 may be yieldingly mounted to prevent jamming during engagement. Speed-indicator transmission mechanism.-The member 4 may be rotated by a connecting-rod 23, Fig. 5, on an armature 21 of electromagnets 20, the circuits of which are closed by a rotary switch 16 on the speed shaft 15. Or one electromagnet and a return spring may be used. In another arrangement, a piston 26, Fig. 6, is reciprocated by pneumatic impulses transmitted from a speed shaft, and rotates the member 4 by a connecting- rod 27, while in a further arrangement, a cam 28, Fig. 7, on the speed shaft 15 rocks an arm 29 connected by an enclosed cable 31 with a connecting rod 36, the return being effected by a spring 35. The effect of dead centres is eliminated by means of a cam 14 on the member 4 engaged by spring pawl 12. A complete speed indicator with distance registering mechanism driven from the wheel of a bicycle is referred to in the Specification, but this subject matter is not illustrated.