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 piston tube assembly (17) for a spring brake actuator (1) includes a first tubular body (35) having a contoured inside surface profile (55) for non-rotationally guiding a running nut (21) of a mechanical release mechanism (19, 21), and an internal breather valve (41) mounted to the piston tube assembly (17) for allowing fluid transport into and out of the piston tube assembly and any volume in fluid communication therewith. The piston tube assembly (17) includes a second tubular body (37) that is of a different material than the first tubular body (35), which encloses the first tubular body (35) and mechanically supports the first tubular body (35), and the internal breather valve (41) is mounted to the first tubular body (35).

In a work vehicle, a through-hole in a stay includes first and second regions. When a grip is pulled in an unlocked state in which a collar is located inside the first region and a grip assembly is not locked inside the through-hole, a state is transitioned into a locked state in which a compression spring is compressed by a pin and a plain washer, a brake lever rotates, a claw moves toward a notch, and a rod is located inside the second region and the grip assembly is locked inside the through-hole. When a brake pedal is stepped on in this locked state, the claw and the notch engage with each other, and the brake pedal is locked.

A pneumatic brake actuator has a housing and a divider that divides the housing into a spring chamber containing a spring and a pressure chamber. The divider has an opening that receives an end of an actuator tube. A bearing that is positioned within the opening in the divider is joined to both the divider and the actuator tube. A caging bolt has a first end positioned within the actuator tube and extends from the first end through openings in the bearing and housing to a second end positioned outside of the housing. The connection between the bearing, divider and actuator tube contains the spring within the housing in the event that the housing and/or divider fails. The divider can be a piston or a diaphragm and pressure plate. The bearing can be joined to either of the divider and actuator tube with threads and/or by welding.

A braking system for an air brake vehicle includes a source of working pressure and a source of vacuum pressure. The system includes at least one brake actuator having a first chamber for receiving the working pressure, a second chamber for receiving the vacuum pressure; and a push rod that moves linearly in response to pressure in the first chamber and second chamber. A brake assembly is mechanically connected to the push rod for applying friction to a wheel end of a vehicle in response to the linear movement of the push rod.

A spring brake chamber for pneumatic braking systems used in heavy commercial vehicles such as buses, trucks, trailers and tractors, includes a power spring configured to detect the parking position, the driving position and the situation in which the power spring is broken. The present invention allows the driver to be notified by sending a signal.

A pressure sensing system of a pneumatic spring brake chamber for a vehicle according to an embodiment of the present disclosure includes a plurality of pressure sensors configured to measure pressure in a pressure chamber formed between a piston and an adapter housing and a service chamber formed between the adapter housing and a diaphragm, a control box electrically connected to the plurality of pressure sensors, and an indicator electrically coupled to the control box, wherein the control box is wired for power supply and output voltage to the plurality of pressure sensors, and the indicator located in a vehicle driver's seat is configured to generate an alarm about an abnormal situation of the pneumatic spring brake chamber for a vehicle based on pressure measurement values in the pressure chamber and the service chamber through the plurality of pressure sensors.

An electropneumatic brake system for a vehicle has a parking brake system having a parking brake valve unit constructed to adjust a parking brake pressure on at least one spring loading connection in accordance with a pilot control pressure. The valve unit has a pilot control unit which in accordance with an electronic parking brake signal adjusts the pilot control pressure on a pilot control path. The parking brake unit has an additional brake pressure connection which is or can be pneumatically connected to the pilot control path to introduce an emergency release pressure. The introduction of the emergency release pressure on the additional brake pressure connection causes the adjustment of the parking brake pressure on at least one spring loading connection. A first control unit is configured to provide the electronic parking brake signal to the valve unit. The electropneumatic brake system can have an emergency release valve unit.

The present disclosure relates to a double-lip seal of a pneumatic spring brake chamber for a vehicle, the double-lip seal has sealing performance between an inner circumferential surface of a through-hole of an adaptor housing and an outer circumferential surface of an actuator rod to prevent degradation in sealing performance of the lip seal, thereby maintaining constant sealing performance and preventing fluid leakage.

A spring brake actuator assembly for actuating a brake includes a spring chamber and a service chamber. A central flange defines opposing first and second cup-shaped sections. A spring chamber housing is interconnected to the first cup-shaped section of the central flange case for defining a spring chamber. A reciprocating piston is disposed in the spring chamber and includes a tubular push rod being biased into the service chamber from the spring chamber by a power spring disposed between the spring chamber housing and the reciprocating piston. The spring chamber is sealably bifurcated into a spring portion and a brake release portion. The brake release portion is subject to pneumatic pressure for compressing the power spring disposed in the spring chamber. A service flexible diaphragm defines the service chamber that is also subject to pneumatic pressure for driving a push rod outwardly of the service chamber to actuate a brake.