| 摘要 |
The invention relates to a new type of variable speed transmission, especially advantageous for agricultural tractors and commercial vehicles, which comprises a combination of a full synchromesh basic transmission (3) with a double clutch (2) and a plurality of gears, shiftable under load, with an auxiliary transmission (4) on the output side with three forwards and one reverse ranges. An essential simplification of the operation is achieved in that the driver shifts the gears of the basic transmission (3) in stages under load by means of the clutch pedal. By means of the manual shift lever of the auxiliary transmission, which is appropriately mounted on the steering wheel, he merely engages another range, thereby declutching and at the same time automatically shifting the suitable gear of the basic transmission (3), so that a continuous series of twelve speeds is obtained with an approximately equal and finely graduated progressive ratio. A considerable reduction of the manufacturing costs is achieved in that only two friction clutches are required which have only to transmit the single engine torque and are accommodated in the flywheel of the engine without taking up additional space; in that individual gear pairs are repeatedly used in different gears, so that compared to the number of shift stages a minimum number of gear wheels and shift positions is achieved. <IMAGE> |
