GB887785A - Improvements relating to power transmission systems - Google Patents

Abstract

887,785. Variable-speed gears. VOITH, G.m.b.H., J. M. Oct. 5, 1959 [Oct. 4, 1958], No. 33724/59. Class 80 (2). [Also in Group XXIX] A power transmission system comprises a controllable engine 1, Fig. 1, which co-operates at least in its lower speed range with a continuously-filled turbo-converter or turbo-coupling provided with automatic control means having an element or elements 46 adjustable in the vortex circuit in dependence on the fuel supply setting of the engine such that they are always in the cut-out setting wherein the flow in the vortex circuit is interrupted for the fuel supply setting corresponding to engine idling and in the cut-in setting for all higher fuel supply settings. The shaft 2 of the engine is connected to a sun-gear 3 which is connected by planetgears 4, 5 and a sun-gear 13 to a shaft 12, and by the planet-gears and their carrier 6 to a hollow shaft 7 connected to the pump 8 of the converter, the turbine 9 of which is connected by a freewheel device 11 to the shaft 12. The shaft 12 is connected to a final output shaft 11 by gearing 22, 23, 24, 26, 27, 28 for forward, neutral or reverse drive, or to a positively-operable change-speed and reversing gear. The vortex circuit of the coupling can be interrupted by an annular slide 46 when a valve 40 connected to the throttle pedal 30 of the engine by a linkage 36, 37, 38 and cam 39 and follower 39<SP>1</SP> is moved to a position permitting fluid pressure from a gear pump or other source to be supplied to a space 45, the position corresponding to the engine idling setting of the throttle and enabling the forward and reverse gears to be easily operated. The movement of the valve 40 may be effected by an electromagnet energized by movement of the throttle pedal. At high-speed ratios, the hollow shaft 7, pump 8 and turbine 9 are held stationary by a brake 18 actuated by a piston-and-cylinder device 16, 17 supplied with fluid-pressure from an automatic changeover control 14, which may be operated by a cam 50 on the same shaft as the cam 39, the drive then being purely mechanical. In another embodiment, the annular slide is disposed within the core space of the converter in its inoperative position. In a further embodiment, the guide blades 307, Figs. 5 and 7, of the converter are pivotally mounted and have toothed segments 308 meshing with a gear 309 rotatable by a piston 312 in a cylinder 313 connected to a valve 319 movable in response to the pressure in the inlet manifold 318 of the engine 301. At idling speed, the relatively high pressure in the manifold actuates the valve and piston to move the blades to the position shown in which they interrupt the vortex circuit, and at higher speeds with lower pressure in the manifold, the blades are moved to their normal operative position. Specification 470,044 is referred to.