MAIN SECTION AND AUXILIARY SECTION TYPE DUAL-COUNTERSHAFT TWELVE-SPEED TRANSMISSION FOR VEHICLE

摘要

A main section and auxiliary section type dual-countershaft twelve-speed transmission for vehicle is comprised of a main section and an auxiliary section. The main section includes a first shaft (1), a second shaft (10) and several countershafts (14) provided on both sides of the second shaft (10). There is gear drive provided between the second shaft and the countershaft. There are six gears on the second shaft, each of which is positioned independently. There are three synchronizers (4) on the second shaft. A shifting fork (5) of the synchronizer is connected to the control mechanism and gear lever by a fork shaft (16). A main shaft (20) and a countershaft (22) are provided in the auxiliary section. The gear (29) engages with the gear (28), and the gear (25) engages with the gear (30). A synchronizer (9), the shifting fork (15) and the fork shaft (31) are provided between the gear (25) and the gear (29). The synchronizer is self-locked by the reverse taper teeth. The fork shaft is self-locked by the mechanism composed of a spring (18) and a steel ball (19).