Abstract: The present invention relates to a hydraulic piston and a process for its surface treatment in order to improve above all the wear resistance and corrosion resistance at the surface of the piston. As a favorable manufacturing process for the surface treatment of an above-mentioned hydraulic piston, a multistage process is disclosed which arranges a nitrocarburization with a subsequent oxidation and a following mechanical solidification of the oxidized surface for the piston. As a result, several superposed layers—layer of oxide, connecting layer, diffusion layer—develop at the piston surface which exhibit the desired qualities.

Abstract: The present invention relates to a hydraulic piston and a process for its surface treatment in order to improve above all the wear resistance and corrosion resistance at the surface of the piston. As a favorable manufacturing process for the surface treatment of an above-mentioned hydraulic piston, a multistage process is disclosed which arranges a nitrocarburization with a subsequent oxidation and a following mechanical solidification of the oxidized surface for the piston. As a result, several superposed layers—layer of oxide, connecting layer, diffusion layer—develop at the piston surface which exhibit the desired qualities.

Abstract: In a plastic brake piston for a disc brake, the heat conductivity is improved because the brake piston is provided with an insert member made of a metallic material which extends from end to end through the brake piston.

Abstract: A clutch master assembly made of plastic material for an automotive vehicle. The assembly a plastic cylinder housing (1) and a piston (2) and a plastic bushing (3). The plastic bushing is arranged to allow it to be screwed in by means of a thread portion (4) which is located in the housing. By the screwing-in of the bushing a grooved disc (5) and a grooved cup (6) are secured in the assembly. The grooved cup is furnished with knobs (21, 22, 23) which exert a force in axial direction on the arrangement consisting of the grooved cup (6) and the grooved disc (5). The piston-side enlarged end of the piston rod (31, 104) is secured within the piston (2, 103) by a back injection.

Abstract: A rear brake pressure proportioning control device is disclosed, with a regulating piston (7) and with a valve closing member (9) being supported within a slidable control piston (8), the movement of the control piston interrupted at a predetermined rate of vehicle deceleration. A restriction (32) between the inlet and inlet chamber within which the control piston is disposed prevents a high rate of brake pressure increase from causing too high a rear brake pressure. A multiple-stage restrictor (26) is positioned in the inlet in order to prevent a very high rate of pressure increase of the brake pressure resulting in too low a rear brake pressure.

Abstract: A vacuum brake power booster is presented in which the vacuum control valve (81) is arranged parallel to the master cylinder (55). The housing (92) of the booster is used as a carrier element for actuating members, such as the brake pedal (60, 8) and the clutch pedal (11) as well as for other elements. A twin master cylinder is employed. A short overall axial length and a space-saving design of the assembly as a whole, enabling efficient incorporation of the overall assembly at the assembly line of the vehicle manufacturer, are achieved by the selection and arrangement of the components of the brake power booster and of the master cylinder, as well as of the actuating members.

Abstract: An anti-locking brake system for automotive vehicles, comprising a tandem master cylinder (1), a device (3, 4) for modulating the pressure supplied to the wheel brakes, an anti-locking control device (2) including a pressure reducing valve (10) located in the rear-axle brake circuit (7). The pressure reducing valve can be activated only in the event of failure of the anti-locking device. To attain a particularly simple and compact design of the re-switchable brakes force distributor (10, 110), an electromagnetic drive (21, 25, 121, 125) is provided and includes an actuating element (20, 120) through which pressure is directly applicable to the valve closing member (16, 116) of the pressure reducing valve (14, 15, 16, 114, 115, 116). To ensure the pressure reducing function even in the event of a failure of the anti-locking device during a brake actuation, an additional arrangement (134, 135, 136) for the volume expansion is provided.

Abstract: The present invention relates to a braking pressure control device for automotive vehicles including a regulating valve, composed of a regulating piston (5) and a valve closure member (6), which governs the connection between a pressure-fluid inlet (3) and a pressure-fluid outlet (4). The valve closure member (6) is coupled to a pressure-responsive displaceable control piston (20). The control device also includes a deceleration responsive deflectable inertia member (33). The displacement of the control piston (20) is controlled as a function of the position of the inertia member. In order to simply accomplish an abrupt and temperature-independent locking of the control piston when a deceleration value is exceeded, the inertia member (33) moves into a mechanical latching engagement with the control piston (20).

Abstract: To warn the driver of an automotive vehicle in the event of failure of a component of the actuating apparatus in a brake pressure control device with two control valves which are acted upon by an actuating varied by an actuating variable which is common for both control valves, a separate actuating apparatus is provided for each control valve. The differential pressure between the pressure fluid outlets is permanently monitored.

Abstract: An anti-lock brake system for automotive vehicles comprising a master cylinder (1), a device for modulating the pressure supplied to the wheel brakes, at least one control device (2), at least one monitoring device and a device for pressure reduction provided in the rear-axle brake circuit (7). In order to maximally utilize the share the rear-wheel brakes have in the total brake force, without causing an unstable vehicle condition thereby, braking pressure reduction is effected only upon failure of the anti-lock device.

Abstract: A clutch master assembly made of plastic material for an automotive vehicle. The assembly a plastic cylinder housing (1) and a piston (2) and a plastic bushing (3). The plastic bushing is arranged to allow it to be screwed in by means of a thread portion (4) which is located in the housing. By the screwing-in of the bushing a grooved disc (5) and a grooved cup (6) are secured in the assembly. The grooved cup is furnished with knobs (21, 22, 23) which exert a force in axial direction on the arrangement consisting of the grooved cup (6) and the grooved disc (5). The piston-side enlarged end of the piston rod (31, 104) is secured within the piston (2, 103) by a back injection.

Abstract: Disclosed is a pressure control device including a housing incorporating a pressure control valve which governs a connection between a pressure-fluid inlet and a pressure-fluid outlet. Included is a deceleration-responsively movable inertia member, and control piston arranged in the housing and being slidable in dependence upon the pressure of the pressure fluid and the position of the inertia member and acting upon the pressure control valve. In order to provide for a pressure control device which is more cost-efficient and which switches precisely irrespective of the viscosity and the flow velocity of the pressure fluid, the inertia member is arranged in a chamber of the pressure control device which is substantially free from pressure fluid and the inertia member controls a valve which isolates a compartment confined by the housing and the control pisotn from the chamber.

Abstract: A pressure regulator for an automotive hydraulic braking system includes a housing provided with at least one pressure fluid inlet and one pressure fluid outlet with a connection between the inlet and outlet controlled by a valve unit driven by a driving force in proportion to an application force. The pressure regulator is substantially located in the interior of a suspension spring of a vehicle. To attain a load-sensitive pressure regulator of high precision, there is provided a fluid enclosed by a membrane which serves to transform the application force to the valve driving force. The driving force is applied to the pressure regulator valve unit through a partial face of the membrane in an opening direction of the valve.

Abstract: The present invention discloses a pressure regulator including a regulating valve disposed in a housing between an inlet and an outlet, with the regulating valve being provided in a regulating piston. The regulating piston is displaceable, in pressure-sensitive manner, against a control force. The valve also includes an inertia element movable in a manner sensitive to acceleration and driving a control piston. To provide a pressure regulator that is inexpensive to manufacture and easy to assemble and having a dynamic pressure characteristic, there is provided a pressure chamber between the control piston and the valve seat of the inertia element which is connected to the main bore, with the volume of the pressure chamber being variable against the force of a resilient element.

Abstract: A floating-caliper spot-type disc brake comprises a brake support member with two radially extending brake-shoe carrying and guiding arms and a floating caliper arranged between the arms. The floating caliper is axially guided by at least one axial bolt supported on the brake support member. For securing the floating caliper in position while mounting or dismounting the axial bolt, both circumferential sides of the floating caliper are provided with extensions which radially inwardly engage underneath abutments disposed on the associated brake-shoe carrying and guiding arms.

Abstract: An arrangement for supplying pressurized fluid into a user circuit, particularly a master cylinder of a clutch, includes a cylinder housing defining a bore. A cylinder sleeve is slidably accommodated in the bore and bounds an external feeding compartment with the housing, as well as an internal pressure chamber. A piston is received in the pressure chamber for displacement in the axial direction of the arrangement in response to the application of an external force, especially that of a clutch pedal, thereto, to exert pressure on the fluid present in the pressure chamber. The sleeve has a connecting port at its end remote from the point of application of the external force, and the housing has an auxiliary port communicating with an auxiliary reservoir and a supply port which communicates with the user circuit.

Abstract: A deceleration-sensitive braking pressure control unit having a ball valve freely movable in an inlet chamber of the housing of the unit. The ball opens or closes a channel for the passage of pressure fluid through a longitudinally slidable, pressurized stepped piston upon attainment of the change-over pressure with the vehicle loaded. The stepped piston is movable in the longitudinal bore of a pressurized annular piston which is supported slidably in the housing. In this arrangement, the annular piston is slidable in the housing to control the pressure fluid passage between its annular end face and the surface of the ball upon attainment of the change-over pressure, with the vehicle unloaded. Both the stepped piston, which contains the channel and the annular piston are comprised of varying effective surfaces acted upon by pressure fluid and are maintained in their initial positions in the housing by springs.

Abstract: The multiple-circuit hydraulic brake system includes a brake-actuating device having three working chambers for actuating wheel brake cylinders. A first brake circuit is connected to a first of the three working chambers and separately to each wheel brake cylinder of the rear axle through a different one of two control valves controlled by the pressure of a second and a third of the three working chambers. A second brake circuit is connected between one of the wheel brake cylinders of the front axle and the second of the three working chambers and a third brake circuit is connected between the other of the wheel brake cylinders of the front axle and the third of the three working chambers. Upon failure of the second and/or third brake circuit, the associated one of the two control valves retain the pressure of the diagonally opposite rear axle wheel brake cylinder below the wheel locking limit.

Abstract: A load-responsive brake pressure control device for vehicle brake systems includes a control valve actuatable by a stepped piston. The stepped piston has one surface of a larger axially effective area which is acted upon in the valve closing direction by the pressure prevailing downstream of the valve, and another surface of a smaller axially effective area which is acted upon in the valve closing direction by the pressure prevailing upstream of the valve. A load-responsive spring acts in the opening direction of the valve on a movable component of a cylinder-and-piston unit, especially on a flange of a cylinder component of such a unit, to urge the same into its initial position in which it abuts a stop surface of a support. The cylinder and piston components of the unit together define a chamber which communicates with a flow path having a stationary portion accommodating a sealing element bounding a passage of a reduced cross section.

Abstract: The brake actuating device is disposed in a cylindrical bore of a disc brake caliper leg and comprises an actuating spindle and an actuating nut interconnected by a ball bearing thread. The actuating spindle has a central bore receiving an adjusting spindle surrounded by a sleeve, one end of which is connected to an adjusting nut threaded onto the adjusting spindle and transmitting the actuating force thereon. The other end of the sleeve is accessible through a bore from the outside of the caliper leg and can be turned with a tool in order to reset the adjusting nut for replacement of the worn brake pads.