GB391837A - Improvements in power transmission systems - Google Patents

Abstract

391,837. Driving-gear for locomotives, vehicles, &c. SINCLAIR, H., 6, The Crest, Surbiton Hill, Surrey. Nov. 5, 1931, No. 30729. [Classes 79 (ii) and 79 (v).] In transmission mechanism for motor vehicles, locomotives, tractors, cranes, &c. comprising, in order, a driving-shaft 2, Fig. 1, a Vulcan, F÷ttinger, or like hydraulic clutch 1, and change-speed gearing 7, a one-way clutch is interposed between the driving-shaft and gearing. In one form, for facilitating speed changing, a roller clutch 9, in parallel with a claw or friction clutch 13, is disposed between the hydraulic-clutch driven shaft 4 and the gear-box driving-shaft 6, a brake drum 18 also being mounted on the shaft 4. The brake band 19, the clutch member 13, and the engine throttle 21 may be operated in due sequence from a com. mon pedal 15, as described in Specification 366,081, an ordinary accelerator pedal (not shown) also being provided. The brake 18, 19 may be arranged, on full application thereof, to reverse the shaft 4 slightly, in order to relieve stresses in the gears, as described in Specification 365,998, [Group XXIV]. The claw-clutch teeth are preferably chamfered. The gear-wheels or claw clutches in the box 7 may be synchronized by friction gears or clutches, e.g. as described in Specification 358,674, [Group XXIV]. In a modification, the one-way and claw clutches are disposed in an extension 70, Fig. 5, of the gear-box 7, the one-way clutch being of the Humfrey-Sandberg type, comprising a driving- cage 60, driven outer conoid 59, floating inner conoid 61 pressed towards engagement by spring plungers 64, and skewed rollers 62. As the spring-returned pedal 15 is released to move the chamfer-toothed claw-clutch driving- member 51 towards the driven member 56, a coned face 69 allows balls 66 to ride up a tapered collar 67 and progressively release a thrust ring 65, and hence the conoid 61, so increasing the magnitude of the forward torque transmissible by the rollers 62. In order to allow appreciable forward torque to be transmitted from the shaft 4 to the shaft 2, as when starting the engine 3 from the road wheels, a reverselyacting one-way clutch may be arranged in parallel with the hydraulic clutch. Fig. 2 shows a simple roller clutch 33, 34, 35 acting between the shaft 4 and an extension 32 of the impeller 30, while Fig. 3 shows a skew-roller clutch 40, 41, 42 replacing the usual spigot bearing between the shaft 4 and the hub 44 of a casing 32a forming an extension of the impeller 30a. The outer conoid 41, pressed by springs 43, may have positive means to limit its axial engaging movement and thus the torque transmissible. The Provisional Specification describes also the following modifications :-the clutch between the hydraulic coupling and the gear-box may comprise forwardly and reversely acting progressive clutches in parallel, both of which may be rendered inoperative for starting, the forward clutch being operative with or without the reverse clutch during normal running, and the reverse clutch inoperative with the forward clutch in or out during gear-changing ; a reverse progressive clutch may be combined with a forward non-progressive free-wheel clutch, with or without a brake for turning back the shaft 4 ; a forward progressive clutch may be combined with a friction clutch, with or without the brake ; in any of the foregoing, the reverse clutch may have torque-limiting means for engine-starting purposes ; the clutch in parallel with the hydraulic coupling may have means to allow transmission of substantial torque in both directions, and may comprise a simple free-wheel clutch combined with a friction clutch ; and the forward free-wheel clutch may be located in the hydraulic-coupling housing, between the driven member and driven shaft thereof.