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.

An electronically controlled pneumatic brake system (2) for a vehicle 100, with a supply coupling head (24), a control coupling head (26), and an electronically controlled trailer control module (28) includes a first supply port (28.1), a trailer supply connection (28.2) for providing a trailer supply pressure (pT) to the supply coupling head (24), a trailer control connection (28.3) for providing a trailer control pressure (pB) to the control coupling head (26), an electro-pneumatic trailer control valve arrangement (40) for providing the trailer control pressure (pB), and a tractor protection valve electronic control unit (42). The electro-pneumatic trailer control valve arrangement (40) is configured to only supply a trailer control pressure (pB) to the trailer control connection (28.3) when compressed air is supplied to the trailer supply connection (28.2).

A system for braking a displacement-controlled drive system (10), which can be driven by means of an inflow pressure and an outflow pressure at an inflow end and an outflow end thereof, respectively, for a motion, characterized in that by means of an electro-proportional adjustment of at least one valve element (26, 28, 126, 128) an outflow volume flow of the drive system (10) is controlled such that the outflow pressure is decoupled from the motion of the drive system and can be freely preset and coupled to the inflow pressure, which can in that way be lowered to the extent necessary for the motion of the drive system (10).

An air brake electric control valve includes a valve body, a force balance unit including a guide member, and an electromagnetic urge unit including a movable column operable to move between an urging position and a retracted position. When the movable column is at the urging position, the movable column pushes the air guide member such that a through hole of the air guide member is blocked. When the movable column is at the retracted position, a gap is formed between the movable column and the air guide member such that an intermediate section and a second passage of the valve body are in fluid communication via the through hole of the air guide member and the gap.

A pressure equalization valve arrangement for a rail brake system includes a hold valve and a membrane vent valve each having a control chamber. The hold valve and vent valve are piloted by a respective solenoid valve. A further solenoid valve is connected to the control chamber of the vent valve to allow the pressure across the vent valve membrane to be equalized with the brake cylinder pressure to decrease the pressure difference across the membrane. This results in an improved vent time.

A parking brake valve device for controlling a storage spring parking brake in an electropneumatic brake system includes a compressed air input configured to be connected to a compressed air supply, a parking brake output configured to control a storage spring parking brake, and a trailer-control control output configured to control a trailer control valve (TCV) for a trailer brake system. The parking brake valve device further includes a relay valve pilot control region and a relay valve, a TCV pilot control region configured to control the trailer-control control output, an inlet valve configured to be controlled with a first electrical control signal for supplying air to the TCV pilot control region and the relay valve pilot control region, and a connecting valve configured to be controlled by a second control signal to connect and disconnect the TCV pilot control region and the relay valve pilot control region.

A valve module is provided for enabling a vehicle to control an autonomous event of the vehicle. The valve module comprises a relay valve, a first solenoid valve, and a second solenoid valve. A first control pressure can be delivered through the first solenoid valve and applied to a control port of the relay valve. In one embodiment, a second control pressure can be delivered through the second solenoid valve and combined with the first control pressure. The combined first and second control pressures are applied to the control port of the relay valve. In another embodiment, a second control pressure can be delivered through the second solenoid valve only when no first control pressure is delivered through the first solenoid valve.

A pressure equalization valve arrangement for a rail brake system includes a hold valve and a membrane vent valve each having a control chamber. The hold valve and vent valve are piloted by a respective solenoid valve. A further solenoid valve is connected to the control chamber of the vent valve to allow the pressure across the vent valve membrane to be equalized with the brake cylinder pressure to decrease the pressure difference across the membrane. This results in an improved vent time.

A brake control valve arrangement for controlling application of a braking force includes an electro-pneumatic brake control valve block including a hold valve and a vent valve (PRESSURE CONTROLLER), a main regulator valve (RELAY VALVE) and an emergency and a variable load control pressure regulator. The valve block has an inlet for a brake supply pressure, and an outlet in pneumatic connection with a brake cylinder. A pilot pressure into the main regulator valve from the variable load control pressure regulator is controlled by a remote release solenoid valve (CONTROL CHAMBER VENT MAGNET VALVE). The remote release solenoid valve adapted to vent brake cylinder pressure to atmosphere when de-energized thereby enabling release of the wheel braking force via the main regulator valve.

The invention relates to an electronically controllable secondary brake system (46), operated by pressure medium, useable as both as a parking brake system and an auxiliary brake system, with spring brake cylinders (68a, 68b) arranged on wheel brakes of at least one vehicle axle (8), with a directly or indirectly electronically controllable brake control valve (56). The brake force of the spring brake cylinder (68a, 68b) can be reduced by a feed of pressure medium and can be increased by a discharge of pressure medium, and with an electronic brake control unit (48) for controlling the brake control valve (56) dependent on the current value of a brake value signal (SBW). The brake control valve (56) is configured as a 3/3-way proportional valve with a pressure medium inlet, a pressure medium outlet, and a working connector, which is connected via a working line (60, 66) to the spring brake cylinders.