| 摘要 |
A two-speed sub-transmission for a vehicle comprising a first transmission line A provided by an engine output shaft 7 directly connected to a drive shaft 10 operatively connected to a main change speed gear mechanism, a second transmission line B provided by the engine output shaft 7 operatively connected to the drive shaft 10 through a reduction gearing mechanism, and clutch means 12, 73 for selecting between the first transmission line A and the second transmission line B to transmit power. In the embodiment shown direct drive is via the hydraulically actuated clutch 12 with one way clutch 73 slipping, whereas clutch 12 is released for reduction such that drive is transmitted via a layshaft 69. A second one way clutch 79 allows the main transmission to turn the engine for starting when the vehicle ignition has failed. In a second embodiment (Figure 4, not shown) there are two hydraulic clutches, mounted coaxially with the input and output shafts, one for direct drive and one for reduction. <IMAGE> |
