GB412306A - Automatic control for variable speed gearing upon motor vehicles - Google Patents

Abstract

412,306. Controlling variable speed gearing ; controlling motor vehicles. VINCENT, C., 61, Rue Joseph Deflandre, Sauheid-Embourg, Liege, Belgium. Jan. 16, 1933, Nos. 1464 and 1465. Convention dates, Jan. 15, 1932 and Feb. 19, 1932. [Class 80 (ii).] An automatic controlling-device for variablespeed gearing on motor vehicles comprises a gear control lever 13, Fig. 1, operated by the free element 11 of a differential device, a second element 4 of which is operated by the accelerator 1, the third element 5 being operated by a centrifugal governor 6 rotating with the roadwheel shaft or with the engine shaft. The engine is thus allowed automatically to turn at the speed at which it develops maximum power. In the arrangement of Fig. 1, the lever 13 controls continuously-variable gearing of suitable construction, not shown, and the governor 6 is driven from the road wheels 10. The differential device comprises two racks 5, 11 with a pinion 4 floating between them. A lever 3 is shown connecting to the engine throttle. An arrangement is described for operating continuously-variable gearing similar to the arrangement shown in Fig. 4 in which a lever 34 there shown controls the gearing directly, as does the gear control lever 13, Fig. 1. The governor 26 is driven from the engine cam-shaft 15 and influences a rack 49. The accelerator, not shown, through a cam 31 operates the other rack 50. The free differential element, a pinion 48, controls the position of the slide valve 19 of a servomotor, the piston 46 of which operates the said gear control lever. The arrangement shown in Fig. 4 is adapted to control a change gear of the step-by-step type. Brakes a, b, c, d of step-wise epicyclic change gearing are operated selectively by a switch 37 which is connected to the lever 34 shown by springs 42. The movement of the switch lever 37 in following the lever 34 is resisted by friction on a fixed electric contact such as b<2>, so that a spring 42 is compressed. When a contact member 44, Fig. 5, of the lever 37 comes to the end of the contact b<2>, as shown, this resistance vanishes so that the lever 37 is shot over by the spring 42 and the contact member 44 jumps the gap to the next fixed electric contact c<2> so as to tighten a different change gearing brake and effect a stepped change in the transmission. If the vehicle is running with the throttle fully open and the accelerator is released, the lever 34, Fig. 4, is pulled right down so that the lever contact 44 passes upwards beyond and clear of the last fixed contact c<2>. This disconnects the drive and the vehicle coasts. This happens only when the vehicle is running fast. At low vehicle speeds, braking by the engine is retained. A hand switch 38 on the vehicle dash-board is moved one way for automatic forward-speed changing, and the other way for reversed driving. An adaptation for operating step-wise change gearing is described, being a development of the arrangement of Fig. 1 in which the governor is driven from the propeller shaft end of the transmission. In this, there is no servomotor and the free differential element carries a lever which acts directly on the lever 34 of the gear-changing switch shown in Fig. 5.