Abstract: A hydraulic change-over valve is adapted for a vehicle brake system with anti-lock control and traction slip control which operates according to the return delivery principle during an anti-lock control operation and the self-priming pump of which takes in pressure fluid through the master brake cylinder during a traction slip control operation. The change-over valve is arranged in the suction line between a pump and a master brake cylinder and shuts off the connection during each pedal-operated braking operation and opens it during each traction slip control operation. To avoid negative effects on the brake pedal feeling, restrictors are provided which prolong the closing time of the switch-over valve so that the fluid volume for switching is received gradually and continuously. The switching position is determined by a diaphragm, whose effective surface depends on its flexure to afford a non-stick-slip operation.

Abstract: A brake pressure control apparatus having a brake pressure master unit, a brake connected to the brake pressure master unit through a pressure line, a pressure-controlled inlet valve which is positioned in the pressure line and through which the brake pressure master unit is connected, in a first switching position, through a restrictor orifice to the brake and which is furnished with a control piston which in one direction is subject to the pressure in the pressure line and in the opposite direction is subject to the action of a spring and of the pressure in a return line which contains an outlet valve which is controllable by a control device, which blocks the return line in its position of rest and which releases the return line in its switching position.

Abstract: A brake system which can be employed both for brake slip control and for traction slip control, wherein the brake slip control is performed according to the return delivery principle, while an open-loop system is set up during traction slip control. In order to manage with the same pump (10) in both cases, a valve system composed of a first non-return valve (16) and a second non-return valve (17) is provided at the suction side of the pump. The opening pressure of the first non-return valve (16) is greater than that of the second non-return valve (17). Further, the initial pressure of a low-pressure accumulator (9) is in excess of the opening pressure of the first non-return valve (16). The first non-return valve (16) is operative during brake slip control, while the second non-return valve (17) is operative during traction slip control. Switch-over can be effected for instance by the master cylinder pressure via a control line (18).

Abstract: A process for adjusting the travel sensor for a brake power booster movable wall is disclosed to compensate for tolerance variations, in which a fixed stop is installed to engage the output member upon applying a predetermined input force to shift the movable wall to a test location. The distance to the test location of the movable wall from a booster housing reference surface is measured with a measuring instrument installed temporarily in the booster housing opening normally receiving the travel sensor. The tips of the travel sensor is positioned at the test location with the travel sensor in the corresponding signal condition either by using an appropriately dimensioned replaceable tip or sensor holder, or by use of an adjustable length sensor holder.

Abstract: A travel sensor for measuring mechanical quantities of motion, in particular for determining the brake pedal position, comprising a transmission unit axially slidable in a housing and comprising a measuring apparatus for generating an electric signal representative of the travel of the transmission unit. The transmission unit is formed of two mechanical transmissions elements (12, 13 and 3, 6, respectively) corresponding with each other and effecting a reduction of the introduced quantity of motions that the test signal is tapped by a reduced test travel. This provides a travel sensor of particularly short dimensions which permits to use of Hall-effect sensors.