GB1416258A - Drive assemblies - Google Patents

Abstract

1416258 Change-speed gear; friction clutches GKN TRANSMISSIONS Ltd 21 March 1974 [28 March 1973] 14856/73 Headings F2D and F2C A motor-vehicle transmission comprises a countershaft or planetary gear 11, in which stepped ratios, excepting first and reverse, are established by plate or cone friction clutches 51, 56, or brakes, and driven through an hydrodynamic torque converter 15 or fluid coupling, associated with two friction input clutches, one 32, 34 a separating clutch between the converter turbine 22 and gear input shaft 31, the other 32, 33 connecting the input impeller shell 15 directly to the gear input shaft 31 to lock-up the converter for wholly mechanical drive, hydraulic, pneumatic or electric means (not described) being provided for operating the ratio clutches under manual or automatic control (not described), responding to output speed and engine torque or speed, and for sequentially, during ratio shift, disengaging whichever of the two input clutches 33 or 34 is engaged, and, after shift, engaging a predetermined one of the said input clutches. The lock-up clutch 33 is engaged in only the upper, or the top, ratios, and when that clutch is to be engaged the clutch 34 may be temporarily engaged first to produce synchronism. In the countershaft gear shown the top four ratios are established by the double cone friction clutches 51, 56, first and reverse by a double toothed clutch 57.