An electro-pneumatic brake system for an automotive vehicle comprising brake actuators each with a service brake chamber and a park brake chamber, a service brake system forming a pneumatic main deceleration system and comprising service brake lines configured to supply air pressure to the service brake chamber of the brake actuators, a park brake system forming a pneumatic immobilization system and a backup pneumatic deceleration system, and comprising park brake lines configured to supply air pressure to the park brake chamber of the brake actuators, wherein the park brake system comprises a pressure controller device configured to perform a wheel anti-locking function under a condition of the park brake system being used as a backup deceleration system, the pressure controller device being configured to control the air pressure supply in the park brake lines.

A valve arrangement for use in a parking brake system of a commercial vehicle or trailer, includes a differential piston having a first section and a second section, wherein the second section has a smaller diameter compared to the first section, and wherein there is a fluidic connection between the first section and the second section. The arrangement includes a housing with a bore, in which the differential piston is adapted to move. The bore has at least two sections, wherein the first section corresponds to the diameter of the first section of the differential piston, and the second section corresponds to the diameter of the second section of the differential piston, and wherein a step is formed between the first section and second section of the bore. A first passage and a second passage are arranged and axially spaced in the bore, and a third passage is arranged in or next to the second section of the bore. When the differential piston is in a first end position, the second section of the differential piston rests against the step, and a connection of the first passage and the second passage within the bore is provided. When the differential piston is in a second end position, a connection of the first passage and the second passage within the bore is blocked.

A parking brake assembly for an electronically controllable pneumatic braking system for a vehicle includes a parking brake unit having a supply connection to receive a supply pressure, a brake request connection to receive a parking brake request, and a parking brake pressure connection to provide a parking brake pressure. The parking brake assembly further includes a first ABS valve unit for a first channel and a second ABS valve unit for a second channel. The first ABS valve unit is configured to provide a pressure for a first spring-loaded brake cylinder at the first channel and to admit air to the first channel, in stages. The second ABS valve unit is configured to provide a second brake pressure for at least one second spring-loaded brake cylinder at the second channel and to admit air to the second channel, in stages.

An electronically controllable braking system for a vehicle is provided. The electronically controllable braking system includes a service brake sub-system and a redundancy brake sub-system. The service brake sub-system includes a front axle service brake circuit with front axle service brakes and a rear axle service brake circuit with rear axle service brakes. The redundancy brake sub-system includes a front axle redundancy brake circuit and a rear axle redundancy brake circuit. A service brake control module is configured to generate a service brake control signal in dependence upon a braking specification for generating a front axle service brake pressure. A redundancy brake control module is configured to generate a redundancy brake control signal in dependence upon a braking specification for generating a front axle redundancy brake pressure.

A spring brake actuator (1) provides a service brake function and a parking brake function and comprises a housing (2) with a housing base (4). A compression spring (14) and a ram assembly (10, 11, 28) with a spring brake piston (28) are provided are provided in the housing (4). The ram assembly separates a spring chamber (12), in which the compression spring (14) is disposed, from a parking chamber (16). The spring brake actuator (1) includes a check valve (50), which is included in the ram assembly to allow an air flow to the parking chamber (16) in case of a compounding condition. The check valve (50) includes a one-way valve, for example a duckbill valve, and a supporting element for securing the one-way valve in the ram assembly.

A compressed-air braking system (DBA*) for a motor vehicle, includes a compressed-air supply device (1) with a compressor (2) and several brake circuits which are connected to the compressed-air supply device (1) via a multi-circuit protection valve (7) and include at least one parking brake circuit with parking brake cylinders (25.1, 25.2). In order to reduce the operating noise of the compressed-air braking system (DBA*) occurring in particular on venting of the parking brake cylinders (25.1, 25.2), it is provided that the parking brake cylinders (25.1, 25.2) can be vented, per wheel or per vehicle axle, alternately either to the surrounding atmosphere or into an additional reservoir (31) via a respective quick-venting valve (29) connected to a connecting line (28) and a changeover valve (30) arranged downstream thereof.

A system for controlling compounding in a vehicle brake actuator includes first and second valves configured to control, respectively, a first fluid pressure in a parking brake chamber of a brake actuator that acts against a spring force applied by a spring of the actuator to a pushrod of the actuator and a second fluid pressure in a service brake chamber of the actuator that applies a fluid force to the pushrod. A controller is configured to receive first and second fluid pressure signals indicative of the first and second fluid pressures, determine a total brake actuator force applied to the pushrod responsive to the first and second fluid pressure signals and control at least one of the first and second valves responsive to the total brake actuator force to adjust a corresponding one of the first and second fluid pressures and thereby obtain an adjusted total brake actuator force.

An electro-pneumatic hand brake system is for a vehicle with spring-loaded brakes. The system includes a pneumatic relay valve, a bistable solenoid valve for controlling the relay valve and a control unit for controlling the bistable solenoid valve. An outlet of the relay valve is connected to ports for the spring-loaded brakes. An inlet of the bistable solenoid valve is provided for connecting to a line carrying ventilation pressure. A self-retaining switching valve with a control input is provided before the inlet of the bistable solenoid valve. The self-retaining switching valve can be moved against the force of a restoring element from a blocking position into a flow-through position when there is sufficient pressure at its control input. An outlet of the self-retaining switching valve is connected to the inlet of the bistable solenoid valve.

A method for emergency engagement of a holding brake of a vehicle having an electropneumatic brake system. The electropneumatic brake system includes a service brake system with a service brake and a holding brake system with the holding brake. The holding brake system has spring brake cylinders. The service brake system includes a service brake control unit. The electropneumatic braking system includes at least one brake circuit for the service brake and the holding brake. The service and holding brakes may be in separate brake circuits. The spring brake cylinders can be vented when a supply pressure in at least one brake circuit for the service brake decreases. The method includes reducing, via the service brake control unit, the supply pressure in at least one brake circuit for the service brake under a program control in defined conditions.

A spring brake actuator for a commercial vehicle includes a service brake portion (4) and a spring brake portion (6) that has a housing (8, 108) with a first end (10, 110) proximal to the service brake portion (4), a wall section (12, 112) extending from the first end (10, 110), a second end (14, 114) distal to the service brake portion (4), and a locking mechanism (16, 116) for locking the first and second ends (10, 110, 14, 114) to the wall section (12, 112). The locking mechanism (16, 116) is arranged between the wall section (12, 112) and the second end (14, 114) of the housing (8, 108).