| 摘要 |
825,687. Variable-speed gear; clutch combinations. DAIMLER-BENZ A.G. Oct. 7, 1957 [Oct. 13, 1956], No. 31364/57. Class 80 (2). A change-ratio transmission in a motor car having an accelerator pedal controlled engine comprises a mechanical gear driven through an hydrodynamic torque converter the pump wheel of which is driven through a two-speed gear giving direct drive and a reduced ratio, establishment of the reduced ratio being effected by kick-down of the accelerator pedal. In one form, an input shaft is fast with a casing 9, Fig. 1, carrying a ring gear 8 meshed by planet gears carried by the impeller 11 of an hydrodynamic torque converter 5. The planet gears mesh a sun-gear 12 mounted through a one-way detent 16 on a stationary casing 17. A fluid coupling 7 is filled to give a virtually direct drive through the input casing 9 and the sun-gear 12 to the torque converter impeller 11, the one-way detent 16 then overrunning. When the fluid coupling 7 is empty, the one-way detent 16 takes the reaction from the sun-gear 12 and the impeller 11 is driven through the planetary gearing at a reduced ratio from the input shaft and the casing 9. The reactor 18 of the hydrodynamic torque converter is mounted through a one-way detent 19 upon the casing 17, and the turbine 22 is fast with a shaft 23. In a modification, the fluid coupling 7 is replaced by a multidisc clutch 24, Fig. 2, engaged to lock the planetary gear for direct drive, and the one-way detent 16 is replaced by a brake 26, engaged when the clutch is disengaged to hold the sungear 12 stationary for the step-down ratio. The fluid coupling 7 is emptied or the multidisc clutch 24 is disengaged by kick-down of the motor-car accelerator pedal. The planetary gear then given its reduce ratio, and maximum acceleration is obtained. The shaft 23 fast with the torque converter turbine 22 is connected in series with a two forward and one reverse ratio planetary gear comprising a sun-gear 28, Fig. 3, meshing stepped planet gears 34 also meshing a sun-gear 31 and a ring gear 37, the planet carrier being fast with an output shaft 33. The ratios are obtained by selective engagement of a multidisc clutch 30, a brake 32 and a brake 36. |
