TRANSMISSION CONCEPT FOR A 6-GEAR COUNTERSHAFT VARIABLE SPEED TRANSMISSION FOR MOTOR VEHICLES

摘要

The invention relates to a transmission concept for a 6-gear countershaft variable speed transmission for motor vehicles, comprising at least one input shaft (1 or 1c/1h) and at least two countershafts (2 and 3) mounted parallel thereto and fitted with a pinion (5 and 6) meshing with an end output gear (8). Fixed gears (F1, F2, F3, F5, F4/F6) are disposed on the input shaft or shafts (1 or 1c/1h) which constantly mesh with the idler gears (L1, L2, L3, L4, L5 and L6). Double or simple synchronizing units (DS1, DS2 and S3 and S4) are provided adjacent thereto by means of which they can be connected to their countershafts (2 and 3) in a selectively driving manner. In a manually selectable manual shift version, the input shaft (1) is impinged upon by a simple coupling (C). In an auxiliary power-actuated powershift version, two concentric input shafts (1c and 1h) are impinged upon by a double coupling (C1 and C2). Successive gears are assigned to the double and simple synchronizing units in such a way that gear shifting from one gear to the next can be performed in a powershifted manner by means of preselection and change of coupling. The gear pairs for the different gears are disposed on the input shafts (1c and 1h) or the countershafts (2 and 3) in the arrangement and geometric layout required for the powershift version. In the manual shift version, when the inputs shafts (1) and the fixed gears (F1' to F6') are changed to match the corresponding countershafts (2 or 3') in a position that is axially modified and rotated by 180 DEG , the corresponding idler gears (L1 to L6) are disposed in identical geometric layout in such a way that successive gears such as (1 and 2; 3 and 4 and 5 and 6) are assigned to a double synchronizing unit (DS1, DS2 and DS3).