A valve system includes an isolation check valve delivering pneumatic fluid as a supply pressure, a double-check valve adapted to deliver a braking demand control signal of the pneumatic fluid based on a higher of a first braking demand in a first pneumatic braking circuit and a second braking demand in a second pneumatic braking circuit, and a control module. The control module is adapted to receive the supply pressure as a control module supply pressure of the pneumatic fluid, receive a control module control pressure of the pneumatic fluid based on the braking demand control signal, and deliver a control module delivery pressure of the pneumatic fluid based on the control module supply pressure and the control module control pressure. A park control module selectively transmits the pneumatic fluid at the supply pressure based on a park brake control signal.

A valve system includes a control module on a tractor portion of a vehicle adapted to receive a supply pressure as a control module supply pressure of the pneumatic fluid, receive a control module control pressure of the pneumatic fluid, and deliver a control module delivery pressure of the pneumatic fluid based on the control module supply pressure and the control module control pressure. A park control module selectively transmits the pneumatic fluid at the supply pressure based on a park brake control signal. A supply glad-hand fluidly communicates the selectively transmitted supply pressure of the pneumatic fluid to supply a brake on an associated trailer portion of the vehicle. A control glad-hand fluidly communicates the control module delivery pressure of the pneumatic fluid to control the brake on the associated trailer portion of the vehicle. An exhaust valve, which fluidly communicates with both the selectively transmitted supply pressure and the control module delivery pressure, exhausts the control module delivery pressure of the pneumatic fluid from the control glad-hand.

The disclosure is directed to a fail-safety valve unit for a parking brake function of an electronically controllable pneumatic braking system for a utility vehicle. The fail-safety valve unit has a monostable release valve and a ventilating valve. The release valve, when energized, provides a release pressure at a first release valve port for the parking brake function and, when de-energized, connects the first release valve port to the ventilating valve. The ventilating valve has a nonlinear ventilating characteristic which permits ventilating of the release valve port from the release pressure to a partial brake pressure with a first gradient, and ventilating of the release valve port from the partial brake pressure to a full brake pressure with a second gradient, wherein the first gradient is greater than the second gradient. A parking brake module and a vehicle are part of the disclosure.

A pneumatic braking device for a utility vehicle includes at least one pneumatically controllable spring accumulator for a parking brake of the utility vehicle and an electronic parking brake device. The electronic parking brake device has at least one electronic control unit, at least one bistable valve unit, at least one first valve unit by which a parking brake of a trailer of the utility vehicle can be deactivated when activating the parking brake of the utility vehicle, at least one second valve device which can be connected in such a way that when there is a decrease in the system pressure for supplying the parking brake of the trailer, the parking brake of the trailer can be activated, and a traction vehicle protection valve.

The invention relates to a driverless transport vehicle for moving a semi-trailer. The driverless transport vehicle comprises a coupling device which is designed to establish a connection with the braking system and/or an electronic system of a semi-trailer. The invention also relates to a method for coupling a driverless transport vehicle to a semi-trailer.

An electronic brake system for a trailer with a pneumatic brake installation is disclosed. The electronic brake system comprises a brake controller (18) in the trailer (11) connected to a first communication device (20) that is part of a first communication channel (23) for wirelessly receiving brake signals of a towing vehicle (10). The electronic brake system also comprises a second communication channel for receiving brake signals of the towing vehicle. The brake controller (18) converts the brake signals of the first communication channel (23) into brake commands for the pneumatic brake installation only if brake signals arrive via the second communication channel (24) at the same time or within a defined time window. The time window begins as soon as a brake signal arrives on one of the first and second communication channels (23, 24).

A pneumatic braking device for a utility vehicle includes at least one pneumatically controllable spring accumulator for a parking brake of the utility vehicle and an electronic parking brake device. The electronic parking brake device has at least one electronic control unit, at least one bistable valve unit, at least one first valve unit by which a parking brake of a trailer of the utility vehicle can be deactivated when activating the parking brake of the utility vehicle, at least one second valve device which can be connected in such a way that when there is a decrease in the system pressure for supplying the parking brake of the trailer, the parking brake of the trailer can be activated, and a traction vehicle protection valve.

A pneumatic braking device for a utility vehicle includes at least one pneumatically controllable spring accumulator for a parking brake of the utility vehicle with an electronic parking brake device. The electronic parking brake device has at least one electronic control unit, at least one first bistable valve unit, at least one second bistable valve unit, at least one valve device which can be connected in such a way that when there is a decrease in the system pressure for supplying the parking brake of the trailer of the traction vehicle, the parking brake of the trailer can be activated, and a traction vehicle protection valve.

A braking system of a trailer and work machine includes a pressurized fluid supply, a hydraulic base valve fluidly coupled to the supply, and a pneumatic base valve fluidly coupled to the supply. A proportional control valve is also fluidly coupled to the supply, and it includes an outlet disposed in fluid communication with the inlets of the hydraulic base valve and the pneumatic base valve. The system further includes a hydraulic output configured to be fluidly coupled to a hydraulic braking system of a trailer, and a pneumatic output configured to be fluidly coupled to a pneumatic braking system of a trailer. The hydraulic output is fluidly coupled to the outlet of the hydraulic base valve, and the pneumatic output is fluidly coupled to the outlet of the pneumatic base valve.

An air supply control arrangement for a heavy-duty vehicle including a lift axle which includes a brake chamber. The air supply control arrangement includes a valve configured to be arranged in an air supply passage that enables pressurized air to be supplied from a pressurized air source to a brake chamber of a lift axle of a heavy-duty vehicle; a processing circuitry configured to receive measurement values of the pressure inside a tire of the lift axle, wherein the processing circuitry is configured to, based on the received measurement values, determine whether the lift axle is in its raised lift condition or in its lowered ride condition, wherein the processing circuitry is configured to control the valve to move to a closed state upon determination that the lift axle has been raised from its ride condition to its lift condition, thereby preventing pressurized air from reaching the brake chamber.