vehicle braking system with means for reducing hjulspinn

摘要

A vehicle having wheels driven via a differential transmission, non-driven wheels and wheel brakes individually associated with the wheels and having wheel brake cylinders has an apparatus for reducing drive slip between the driven wheels and a road surface located beneath these wheels. The apparatus includes a control unit, which is connected to angular velocity wheel sensors for rotational wheel angle associated with the wheels and has at least one differentiating device, which emits control signals whenever drive slip exceeds a preselected switching threshold. By using the control unit, brake pressure control valves of the slipping wheels are controlled such that brake pressure in their wheel brakes builds up (P2). The pressure buildup is terminated as soon as the differentiating device ascertains that a drop of the angular wheel accelerations have dropped below a maximum value. Subsequently the brake pressure initially remains substantially constant. This has the advantage of avoiding the danger of abruptly choking off an internal combustion engine in the vehicle when the vehicle is being started up on a road surface having greatly varying traction.