VERFAHREN UND EINRICHTUNG ZUM AUTOMATISCHEN SCHALTEN DES GETRIEBEGANGES EINER KUPPLUNGSGETRIEBEEINHEIT.

摘要

1. A process for automatically controlling a change in transmission ratio in a gearbox connected to a drive engine, for example of a motor vehicle, by a friction clutch (17), said gearbox comprising a locking action involving synchronisers (17-19) and dog clutches (22a-22c) and a primary shaft (14) which during the shift from one transmission ratio to another is capable of being simultaneously disconnected mechanically from the clutch and the secondary shaft connected to a member driven in rotation, said synchronisers being capable of preventing the dog clutch engagement of a transmission ratio as long as the synchronisation members in frictional contact have not been synchronised and the accelerator control (33) of the drive engine being inhibited or returned towards the idle position throughout the duration of the change in a transmission ratio, characterised in that in the course of shifting form one transmission ratio to another after disengagement of the clutch (2 to 8) the evolution in the angular acceleration or deceleration respectively of the primary shaft (14) is monitored and that clutch reengagement is initiated as soon as the acceleration or deceleration of the primary shaft, after having passed through a respective high threshold in respect of maximum acceleration or maximum acceleration or maximum deceleration which is markedly higher than the levels of acceleration or deceleration caused by normal operation of the gearbox with a transmission ratio engaged, again reaches a low predetermined value at a low threshold, indicating that synchronisation has occurred.