Patent GB-689057-A (GB)
Title: Improvements in or relating to vehicle driving arrangements
IPC: F16H47/06
Filed: 1950-07-17
Abstract: 689,057. Change-speed gear. KRUPP LOKOMOTIVFABRIK, F. July 17, 1950 [July 30, 1949], No. 17809/50. Class 80 (ii). [Also in. Group XXXI] In a hydro-mechanical drive for a vehicle, in which a power distributing transmission is arranged to drive, according to the speed required, varying numbers of axles, the wheels of which are not coupled by connecting rods, and reversing gears co-operate with the transmission so that, at the speed at which the whole power is taken by a single axle, one axle is driven for forward travel and another for reverse travel, the reversing gears are driven by a system of gear wheels, constituting the transmission, one member of which is directly driven at all speeds, both forward and reverse, by a single hydraulic torque converter. In the embodiment shown in Fig. 1 a non-reversible prime mover (e.g. an internal combustion engine or a steam turbine) drives the hydraulic torque converter 1, a differential gear mechanism 4 and gearing shafts 12, 20 which are connected by bevel gearing to the axles 15, 23, the gearing being arranged that at one speed only the rear axle is driven in each case, the differential mechanism effecting two speeds. The torque converter 1 has its output shaft 2 connected to the planet carrier 3 of the differential gear, whilst one sun gear 6 thereof is connected by a shaft to a gear 10 through a free wheel device 9 and a brake 24 and the other sun gear 7 is connected by a hollow shaft 16 to a gear 17 meshing with a reversing idler (not shown). The shafts 12, 20 slidably carry gears 11, 19 and in the full line position of which gears the axles 15, 23 are driven with the brake 24 released and only the axle 23 is driven with the brake 24 applied and in the dotted line position of which gears the axles 15, 23 are driven when the brake 24 is released and when it is applied only the axle 15 is driven, moving in the opposite direction. In the embodiment shown in Fig. 3 the differential mechanism is arranged to give three speed ratios and the shafts 12, 20 carry clutch sleeves 35, 36 to engage one or the other of gears 29, 33 and 30, 32, the gears 29, 30 meshing with a gear 28 connected by a hollow shaft 27 to the planet carrier 3 of the differential mechanism and the gears 32, 33 meshing with a gear 31 connected by a free wheel device 34 to a shaft 26 connected to one sun wheel 7 of the differential mechanism, the shaft 26 carrying a brake 37 and a clutch 38 being arranged between the gear 28 and the shaft 26. In the first gear both axles 15, 23 are driven, the brake 37 and clutch 38 being released and the ratios of the gearing 28, 29, 30 and 31, 32, 33 compensating difference in speeds between the shafts 26, 27 due to the differential mechanism. Reversal of the drive is obtained by opposite movements of the sleeves 35, 36. In the second gear the brake 37 is locked so that the drive is taken from the gear 28 either the gears 29 or 30 being positively engaged with the respective driving shaft 12 or 20 depending on the direction of drive required, the other shaft being connected to the gear 31 and the free wheel device 34 operating. In the third gear the clutch 38 is operative and the brake 37 is released, the clutch rendering the differential mechanism inoperative and only one axle is driven dependent on which direction of drive is required, the appropriate gear 29, 30 being positively engaged with its respective driving shaft and the other driving shaft is connected to the gear 31 with the free wheel device 34 operative. Fig. 4 shows an arrangement of the parts shown in Fig. 3 mounted on a bogie of a railwav vehicle, an engine 61 driving the torque converter 1 through a free wheel device 62 and gearing 65, 66, a casing 67 housing the gearing 29, 30, 32, 33 and an intermediate transverse beam of the bogie being shown at 60.