Device for controlling 4wd vehicle central differential restriction device according to front and rear wheels rotational speed difference, and method of operation thereof.

摘要

In a four-wheel drive vehicle, a central differential (10) receives rotational power from an engine (1) and provides it to the combination of the front wheels and also to the combination of the rear wheels of the vehicle. This central differential (10), includes a torque distribution control clutch (21) for selectively restricting its operation. A control device (45, 22) is provided for this clutch (21) operating in a way so that the operation of the central differential (10) is substantially not restricted when the difference between the rotational speed of the combination of the front wheels of the vehicle and the rotational speed of the combination of the rear wheels of the vehicle is not greater than a determined value, while, when the difference between the rotational speed of the combination of the front wheels of the vehicle and the rotational speed of the combination of the rear wheels of the vehicle is greater than the determinant value, the amount of restriction of the operation of the central differential (10) is increased gradually. The method of operation of the controller (45) is also disclosed.