Abstract: In a known dual-circuit braking pressure control valve, a tilting lever arrangement is provided for distribution of the preloading force to the two control pistons, whereby the change-over point of the intact brake circuit is increased upon failure of one brake circuit. The tilting lever arrangement is complicated with respect to its construction and assembly, and its mode of operation is not safe. According to the present invention the tilting lever arrangement is replaced by a carrier bridge at the ends of the two pistons which synchronizes the points of application of the preloading forces by allowing a slight relative movement betweeen the two pistons when both of the brake circuits are operative.

Abstract: A known pressure control valve for vehicular hydraulic brake systems comprises a valve inserted between an inlet and an outlet with a control piston acting as a valve closure member and slidable in opposition to a spring force. The control piston cooperates with a sealing device encompassing the control piston, the sealing device carrying a valve seat and acting as a check valve from the outlet to the inlet. In accordance with the present invention the control piston is supported in an annular member which is axially slidable in a tubular member and a compression spring to provide the spring force is disposed outside the tubular member with at least one surface against which the compression spring abuts being adjustable during assembly.

Abstract: Dual circuit pressure control valves for brake system are known in which the control pistons are located parallel to each other with each control piston controlling a different one of two brake circuits. Both control pistons are loaded by a common preloading force. The known arrangement is complicated in its construction and has a large overall length. According to the present invention, the construction is simplified and the overall length is reduced by providing a torsion spring which provides the preloading force acting on the control pistons via stationarily supported swivelling levers.

Abstract: Dual-circuit pressure control valves are known in which the control pistons are acted upon by a common control force. A preload distributor constructed as beams of balance to compensate for differences in the control behavior of the two control valves due to manufacturing tolerances have not provided the desired compensation. Therefore, according to the present invention an improved compensation arrangement is provided in the form of a compensating piston which is subjected to the outlet pressures of the two brake circuits.

Abstract: The brake fluid reservoir warning arrangement responds when the fluid level drops below a predetermined minimum level and includes two contact pins and a contact disc arranged on a float to electrically connect the contact pins when the fluid level is below the minimum level. Checking arrangements to check the warning arrangement are disclosed which include manual swivelling or axially displacing the contact pins to make an electrical connection with the contact disc, or the contact carrier includes an opening accessible to both contact pins receiving a metal part to electrically connect the two contact pins together.

Abstract: The reservoir includes a housing, a separating wall in the housing in the transverse direction of the vehicle to provide two chambers, each of the two chambers being divided by a partition in the longitudinal direction of the vehicle into a large and a small chamber compartments. The two chambers are interconnected by a first port in the partition of one of the two chambers spaced from the separating walls interconnecting the large and small chamber compartments of the one of the two chambers, the small chamber compartment of the one of the two chambers, a second port in the separating wall interconnecting the small chamber compartment of the one of the two chambers with the small chamber compartment of the other of the two chambers and a third port in the partition of the other of the two chambers spaced from the separating wall interconnecting the large and small chamber compartments of the other of the two chambers.