GB707259A - Variable speed transmission device, particularly intended for motor vehicles - Google Patents

Abstract

707,259. Hydro - mechanical variable - speed gear. KREIS, F., and SOC. ITALIANA BREVETTI AUTOMOBILISTICI, AR.L. Dec. 13, 1951 [Dec. 15,1950], No. 29207/51. Class 80 (2) A variable-speed gear between an input drum 5 and aligned output shaft 2 on a motor-vehicle, . comprises an input-driven torque-converter 10 providing a countershaft geared ratio 8, 15; 19, 20 for starting only ; an input-driven centrifugal friction clutch 3, providing an allmechanical direct-drive; and one or more additional input-driven centrifugal friction clutches 4, providing one or more additional allmechanical countershaft-geared reduction ratios and mounted on a hollow shaft or shafts 7 concentric with the output shaft 2 and passing through the torque converter, the input impeller of which latter is free on the outermost hollow shaft 7, whilst its turbine 10 is either fast thereon or drivingly connected thereto as by a freewheel 11 with a locking dog-clutch 14 for enginebraking through the converter. In operation, at a predetermined speed, converter drive through the countershaft train, is automatically superseded by mechanical drive through the clutch 4 and same countershaft train, with overrun of the converter turbine at 11, whilst at a higher predetermined speed the direct all-mechanical drive clutch 3 engages, and the last geared-wheel 20 is overrun in a free-wheel mounting 21, which latter may be locked by a dog-clutch 22 for engine braking. Additional geared trains and clutches, where provided, give intermediate speed stages. Reverse is by a sliding wheel 17 and idler not shown.