| 摘要 |
A combined shift control for a motor vehicle driveline comprising a change speed gear transmission and a two speed axle whereby, for instance, a five speed gear box with one reverse gear is effectively extended to provide a seven speed driveline with one reverse gear. The gear box includes three parallel shift rods (12, 13, 14) each carrying a respective selector block (15, 16, 17). The slot (18) of the fourth/fifth selector block (17) is deeper than usual so that the gear lever (21) can operate it in two different transverse positions. In the first position the gear lever (21) actuates the fourth and fifth gears, but in the second position, after overcoming a spring-loaded plunger (20) and operating two micro-switches (24) which serve to change the axle ratio to a higher value, the gear lever (21) effectively actuates two further driveline speeds (sixth/seventh) when selector block 17 is caused to move the shift rod 14 to engage fourth and fifth transmission gears again. In order to retain the gear lever (21) in the high axle ratio position when the driver lets go of the lever means such as a slidable gate (22) which is locked into position when the high axle ratio is selected via the micro-switches (24) are provided. Alternate forms of switch and retaining means are described with reference to other Figures. An embodiment is disclosed in (FIGS. 12, 13) for use with a selector finger mounted on a cross shaft rather than a pivotable gear lever of FIG. 4. |
