Control of differential lock for motor vehicle gearbox - has lock closed during load changes, with locking degree dependent on travel conditions, but not closed in defined speed ranges

摘要

A procedure for controlling the differential lock of a motor vehicle gearbox, particularly the "longitudinal lock" of an intermediate differential of a four-wheel-drive vehicle is described. The lock has a hydraulically operated friction clutch which is opened or closed at defined operating states of the car. The "longitudinal lock" is automatically closed during a change in load. The locking degree is controlled depending on the travel conditions. The lock is closed from traction to overrun of the car and is held with decreasing degree of locking during overrun. The lock is closed over a defined variable time interval dependent on the travel conditions. The lock is not closed in defined speed ranges.