FOUR-WHEEL DRIVE TRANSMISSION FOR A MOTOR VEHICLE

摘要

A multiple-disk visco-clutch is arranged in the drive line of the front axle and the rear axle of a four wheel-drive motor vehicle. In order to prevent an overheating of the multiple-disk visco-clutch, such as when the vehicle is being towed, the visco-clutch is separable from the drive line by means of a shiftable toothed clutch. The lubricating-oil pressure, the intake pipe vacuum or other characteristic quantities of the motor vehicle may be used for actuating the toothed clutch when the internal-combustion engine is stopped, thereby automatically causing the separating of the multiple disk visco-clutch from the drive line.