Daimler-benz Ag

Jurgen Frank

Hellmut Krohn

Manfred Link

Arno Rohringer

Jurgen Pickard

Werner Kruse

A propulsion control device for a motor vehicle which has a permanently balanced all-wheel drive, wherein the drive slip thresholds at which the control responds in the sense of a braking action, is increased as a function of the velocity and decreased as a function of the transverse acceleration. The acceleration thresholds, at which the control responds, are lowered as a function of the transverse acceleration. In the case of travel in a straight line, the lowest of the wheel peripheral velocities is taken as the reference velocity relative to which the drive slip thresholds are fixed. In the case of travel in a curve, the average of the wheel peripheral velocities of the left-hand side and right-hand side vehicle wheels is taken as the reference velocity for the vehicle wheels on the left-hand side and the right-hand side of the vehicle, respectively. From the time t.sub.0 at which the control at one of the vehicle wheels comes into operation, the velocity of this vehicle wheel is updated in accordance with the expression

Device for propulsion control for a motor vehicle with all-wheel drive

A thrust-control device for a motor vehicle having wheels driven on one axle, with a dual-circuit brake system having a tandem main brake cylinder and a brake booster supplied from a special auxiliary pressure source, with an anti-lock system having a brake-pressure medium return device, and with a pressure accumulator serving for thrust control, is extended for use on vehicles with a connectable or permanent all-wheel drive, to the effect that a stop valve is arranged in the brake circuit of the wheels of the further axle and there is a control valve controlling the accumulator pressure and acting on a pressure modulator, the pressure modulator influencing the brake pressure in the brake circuit of the wheels of the further axle when the drive of these wheels is connected and drive slip occurs. This simple extension requires no additional accumulator and makes it possible to preserve the independence of the brake circuits.

Thrust-control device for a motor vehicle

A shifting arrangement for the shifting between a single-axle standard drive and an all-wheel drive having a first clutch for the locking of a central differential gear and a second clutch for the connecting and disconnecting of one vehicle axle actuated by first and second pressure medium control element respectively against the force of a spring having first and second shift valve respectively controlled by an electronic control unit, to either supply working pressure or relieve from pressure respective control elements. The improvement including a hydraulic identifying valve for bringing the control elements into a mutual interaction. The identifying valve operates, as a function of the working pressure of at least one of the control elements and exclusively during the simultaneous controlling of both shift valves, in such a way that the clutch torque at both clutches increases and decreases approximately to the same extent. As a result, when shifting into a shift step with a balanced all-wheel drive from standard drive, a shifting can first take place for a short time into an intermediate step with a longitudinally locked all-wheel drive for securing the driving stability.

Shifting arrangement for two clutches for the shifting between a

A vane for a hydraulic vane pump, with the vane being adapted to be inserted, with sliding movement, into a guide slot provided in a rotor so as to be symmetrical and parallel to a central plane of the slot. The plane forms a setting angle at an outer jacket of the rotor together with an axial plane containing the rotor axis so that an opening of the slot located at the outer jacket of the rotor leads the bottom of the slot in a direction of rotation. A convex sliding sealing surface cooperates with inner jacket of the stator and a pressure surface is located in the plane directed toward a bottom of the slot. A crown of the sliding sealing surface is displaced, with respect to the principle plane of the vane, in a direction opposite the rotational direction of the rotor. The sliding sealing surface forms, in a direction of rotation of the rotor, a wedge-shaped transistional area located at a plane which forms a complimentary angle combined with an addendum angle to the principle plane of the vane. The pressure surface forms, with the principle plane of the vane, a complimentary angle and, when combined with a re-setting angle, forms a 90.degree. angle. The angle formed by the pressure surface is such that a pressure which results at the pressure surface includes a balancing pressure component which is directed approximately at right angles to the principle plane of the vane and approximately in a direction opposite to the rotational direction of the rotor.

Growing community of inventors

Reichenbach, Germany

Jurgen Frank