Process and device for controlling locking differentials

Claim 1

A process for continuously controlling the degree of locking of externally controlling locking differentials in a drive axle of a multi-axle vehicle having driven wheels and non-driven wheels, comprising the steps of: determining a nominal value (Δ v soll) of differential speed for the driven wheels (H L , H R ) as a function of vehicle speed (V F ) determined at the non-driven wheels (V L , V R ); and recording and readjusting the wheel speed differential (Δ v ist) between the driven wheels (H L , H R ) on the nominal value of the differential speed, for offsetting the influence of interfering factors including gripping conditions, wheel load, steering angle or driving torque, by varying the locking effect, the nominal value (Δ v soll) of the differential speed always being different from nil.

Claim 10

A device for controlling the degree of locking of differential drives (1) having a locking coupling (2) in a driven axle of a multi-axle vehicle, with speed sensors at the driven wheels and at least one speed sensor at a non-driven axle, and with a regulating unit (4), comprising: first functional computer means (4 2 ) to which the at least one speed sensor at the non-driven axle (V L , V R ) is connected, the computer means calculating vehicle speed (v F ) and a value corresponding to steering angle (δ); second functional computer means (4 3 ) connected to said first functional computer means (4 2 ), for calculating a nominal value (Δ v soll) of a differential speed for wheels of the driven axle (H L ), H R ) as a function of vehicle speed and said value corresponding to steering angle (δ) or selecting it from a data store in dependence upon speed; third functional computer means (4 1 ) to which the speed sensors at the wheels of the driven axle (H L , H R ) are connected, for calculating wheel speed differential (Δ v ist); and fourth computer means for comparing the nominal value (Δ v soll) of the differential speed with the wheel speed differential (Δ v ist) and, via a functional computer unit with a regulating function (4 4 ), controlling a control member for the locking coupling (2) of the differential drive.

Claim 11

A device for controlling the degree of locking of differential drives (1) having a locking coupling (2) in a driven axle of a multi-axle vehicle, with speed sensors at the driven wheels and at least one speed sensor at a non-driven axle, and with a regulating unit (4), comprising: first functional computer means (4 2 ) to which the at least one speed sensor at the non-driven axle (V L , V R ) is connected, the computer means calculating vehicle speed (v F ) and a value corresponding to steering angle (δ); second functional computer means (4 3 ) connected to said first functional computer means (4 2 ), for calculating a nominal value (Δ v soll) of a differential speed for wheels of the driven axle (H L ), H R ) as a function of vehicle speed and said value corresponding to steering angle (δ) or selecting it from a data store in dependence upon speed; third functional computer means (4 1 ) to which the speed sensors at the wheels of the driven axle (H L , H R ) are connected, for calculating wheel speed differential (Δ v ist); and fourth computer means for comparing the nominal value (Δ v soll) of the differential speed with the wheel speed differential (Δ v ist) and, via a functional computer unit with a regulating function (4 4 ), controlling a control member for the locking coupling (2) of the differential drive.