A spring brake actuator has a service brake with a service brake housing and a service brake working chamber located in the service brake housing. The service brake working chamber is confined by a diaphragm. A service brake piston movable along an actuator-longitudinal axis and abuts the diaphragm, which applies a brake force onto the service brake piston. A spring between the service brake piston and the service brake housing pushes the service brake piston against the direction of the brake force. A modulator valve unit communicates with the service brake working chamber and is configured to regulate the inlet and outlet of fluid into and out of the service brake working chamber. The modulator valve unit is integrated into the spring brake actuator and includes a controllable inlet valve communicating with the service brake working chamber and a controllable outlet valve communicating with the service brake working chamber.

A relay valve (10) for a pneumatic valve unit (14), for example for a braking system of a utility vehicle, has a first assembly component (18) and a second assembly component (20). A hollow cylindrical guide portion (28) of a piston (24) of the relay valve (10) is received, in an axially guided manner, in the first assembly component (18). The second assembly component (20) includes additional valve components and the venting region of the relay valve (10). At least the first assembly component (18) and the second assembly component (20), when assembled, form a preassembly unit (26) first assembly component (18) and are joined by a bayonet connection (30). The preassembly unit (26) is inserted into a housing (12) of the valve unit (14), The interior of the housing is delimited by a cup-shaped inner wall (32), and the preassembled unit is fastened therein.

A method for adjusting brake pressures at pneumatically actuated wheel brakes of a vehicle includes receiving an external braking demand. The method further includes, in response to the received external braking demand, performing, during each of a plurality of computation cycles: (i) ascertaining control signals for pressure control valves of the pneumatically actuated wheel brakes of the vehicle, (ii) continuously ascertaining a differential slip value, wherein the differential slip value is a difference between a slip of two axles of the vehicle and is determined by measuring signals supplied by speed sensors of wheels of the vehicle, (iii) evaluating the differential slip value with respect to a predefined or adjustable setpoint differential slip value, (iv) based on the evaluation of the differential slip value, adapting the ascertained control signals, and (v) releasing the adapted control signals to the pressure control valves.

A relay valve (10) for a pneumatic valve unit (14), for example for a braking system of a utility vehicle, has a first assembly component (18) and a second assembly component (20). A hollow cylindrical guide portion (28) of a piston (24) of the relay valve (10) is received, in an axially guided manner, in the first assembly component (18). The second assembly component (20) includes additional valve components and the venting region of the relay valve (10). At least the first assembly component (18) and the second assembly component (20), when assembled, form a preassembly unit (26) first assembly component (18) and are joined by a bayonet connection (30). The preassembly unit (26) is inserted into a housing (12) of the valve unit (14), The interior of the housing is delimited by a cup-shaped inner wall (32), and the preassembled unit is fastened therein.

This disclosure relates to an air brake system for a vehicle having a front set of wheels having a front air brake and a rear set of wheels having a rear air brake. The air brake system comprises a front air brake cylinder included in the front air brake, and a rear air brake cylinder included in the rear air brake. A foot valve having a first side and a second side is included. A primary air tank is pneumatically connected with the second side of the foot valve, and a secondary air tank is pneumatically connected with the first side of the foot valve. A rear relay valve is pneumatically connected with second side of the foot valve and is pneumatically connected with the rear brake cylinder. A front relay valve is pneumatically connected with the first side of the foot valve and pneumatically connected with the front brake cylinder.

A system on a tractor for controlling trailer service brakes comprises a manually operated trailer brake switch, a first electropneumatic valve in communication with a pressure source and a controller. The controller has an input communicating with the trailer brake switch, an output communicating with the electropneumatic valve and control logic. The control logic receives an input from the trailer brake switch indicating a driver's request to apply the trailer service brakes of the combination vehicle, determines if a predetermined condition exists and transmits a signal to the output to the electropneumatic valve. The electropneumatic valve transmits pressure to a trailer service control line to actuate the trailer service brakes in response to the trailer brake switch and existence of the predetermined condition.

An electropneumatic brake control module (1) for utility vehicles (100) includes a supply port (2) for connecting a compressed air supply (3); a first axle channel port (4); a pneumatically controlled inlet/outlet valve unit (10) for outputting a first braking pressure (PB1) at the first axle channel port (4); and an electropneumatic pilot control unit (8) for outputting at least one first control pressure (P1) at the inlet/outlet valve unit (10). The brake control module (1) further includes a redundancy pressure port (6) for receiving a redundancy pressure (PR) and a redundancy valve unit (12) connected to the redundancy pressure port (6) for outputting a redundancy braking pressure (PBR) at the first axle channel port (4) in the event that the electropneumatic pilot control unit (8) has a fault.

The present disclosure relates to a method for operating a vehicle brake. The vehicle brake includes a hydraulic service brake having an actuating piston, which for generating a first braking force component is movable, under the action of a hydraulic pressure, into an actuating position in which the actuating piston presses a friction lining against a rotatingly supported brake disc, and an electric parking brake, with an actuating element, that is designed to build up a second braking force component that acts on the brake disc. The method includes ascertaining the hydraulic pressure, determining a first braking force component, establishing a second braking force component to be set by means of the parking brake, based on the first braking force component and a desired total braking force, and establishing a position of the actuating element of the parking brake to be set.

A foot brake valve (2′) of a pneumatic brake system in a motor vehicle has an installation plate (4′), on which a brake pedal (14) is pivotably mounted and to which a housing (18′) of a control unit (16, 26) is fastened. A spring-loaded plunger piston (36) in actuating contact with the brake pedal (14) is guided axially movably in an annular collar (50) projecting upward out of the installation plate (4′). For fastening the housing (18′) of the control unit (16, 26) to the installation plate (4′), the housing (18′) has an intermediate flange (48) which is screw-connected to the main part of the housing (18′) and has the annular collar (50). The intermediate flange (48) is coaxially rotatably about a vertical central axis (32), and is connectable in non-positively locking fashion to the installation plate (4′) via a releasable clamping connection (62).

A solenoid valve for brake system includes a valve housing installed in a modulator block, and having an oil flow path; a valve seat installed in the inside of the valve housing, and forming an orifice; an armature configured to move up and down by a magnet core in the valve housing, and to open or close the orifice; a sleeve coupled with the valve housing, and accommodating the armature therein; a restoring spring configured to provide an elastic restoring force to the armature to close the orifice normally; and a damper member interposed between the magnet core and the armature.