| 摘要 |
A multi-speed main gear set is shiftable by a hand lever. A two- speed auxiliary gear set is shiftable by a piston-cylinder unit 8, 7, which is controlled by a control valve 10. A gearshift shaft 1 is shiftable by the hand lever as it moves to select a gate slot and is rotatable by the hand lever to engage a selected gear. The piston- cylinder unit 8, 7 is pressure-relieved by a second control valve 14 in response to a turning of the gearshift shaft 1 from its neutral position, in which the gearshift shaft is normally held by a locking piston 6. The latter is controlled by a third control valve 17, which causes the locking piston 6 to release the gearshift shaft 1 for a turning out of its neutral position only when the piston 8 of the piston- cylinder unit 8, 7 is in either of its end positions. <IMAGE> |
