Abstract: A vehicle brake system includes a hydraulic service brake system having a service brake circuit and a trailer brake control system. The trailer brake control system includes a trailer brake valve with a service brake demand input port and a trailer brake demand output port connected to a trailer brake control coupling. The output at the trailer brake demand output port is dependent on the pressure applied at the service brake demand input port. An electronic trailer brake control system has a solenoid control valve to connect the service brake demand input port to a source of pressurized hydraulic fluid to trigger an output at the trailer brake demand output port. An ECU is configured to actuate the control valve to apply the trailer brakes if it determines that the vehicle is at risk of jack-knifing. The system may also include a shuttle valve.

Abstract: A brake module for a hydraulically braked tractor coupled to a pneumatically braked trailer has a trailer control valve connected via hydraulic control inlet to a hydraulic pressure line leaving a master brake cylinder, and via pneumatic inlet to a compressed air reservoir. Hydraulic control pressure determines pneumatic output pressure level at a trailer control valve pneumatic outlet. The brake module has a break-off prevention module which, if the control line leaks or separates from the trailer control valve relative to the trailer brake system, closes a supply pressure coupling head supply line and causes trailer brake system venting. The break-off prevention module has a pneumatic supply pressure inlet and a pneumatic tear-off control pressure inlet connected to the air reservoir independently of trailer control valve pressure inlets. Supply pressure inlet supply pressure passes through the break-off prevention module and feeds to a trailer control valve pneumatic supply pressure inlet.

Abstract: A brake module for a hydraulically braked tractor coupled to a pneumatically braked trailer has a trailer control valve connected via hydraulic control inlet to a hydraulic pressure line leaving a master brake cylinder, and via pneumatic inlet to a compressed air reservoir. Hydraulic control pressure determines pneumatic output pressure level at a trailer control valve pneumatic outlet. The brake module has a break-off prevention module which, if the control line leaks or separates from the trailer control valve relative to the trailer brake system, closes a supply pressure coupling head supply line and causes trailer brake system venting. The break-off prevention module has a pneumatic supply pressure inlet and a pneumatic tear-off control pressure inlet connected to the air reservoir independently of trailer control valve pressure inlets.

Abstract: A tire pressurization arrangement on a vehicle in which the pressurization of the tire is controlled by a vehicle control unit and the vehicle control unit is notified of a desired tire pressure or desired tire volume. An air flow rate in a supply line to the tire is established so that the time to pressurize the tire to the desired tire pressure/volume is calculable, or the time taken to pressurize the tire to an interval pressure/volume is calculable, said interval pressure/volume being between a current tire pressure/volume and the desired pressure/volume, and if the time to pressurize the tire to the desired pressure is exceeded, the control unit gives a warning signal and/or stops deflation or inflation.

Abstract: A tire pressurization arrangement on a vehicle in which the pressurization of the tire is controlled by a vehicle control unit and the vehicle control unit is notified of a desired tire pressure or desired tire volume. An air flow rate in a supply line to the tire is established so that the time to pressurize the tire to the desired tire pressure/volume is calculable, or the time taken to pressurize the tire to an interval pressure/volume is calculable, said interval pressure/volume being between a current tire pressure/volume and the desired pressure/volume, and if the time to pressurize the tire to the desired pressure is exceeded, the control unit gives a warning signal and/or stops deflation or inflation.

Abstract: A tire pressurization arrangement on a vehicle in which the pressurization of the tire is controlled by a vehicle control unit and the vehicle control unit is notified of a desired tire pressure or desired tire volume. An air flow rate in a supply line to the tire is established so that the time to pressurize the tire to the desired tire pressure/volume is calculable, or the time taken to pressurize the tire to an interval pressure/volume is calculable, said interval pressure/volume being between a current tire pressure/volume and the desired pressure/volume.

Abstract: A tyre pressurisation arrangement on a vehicle in which the pressurisation of the tyre is controlled by a vehicle control unit and the vehicle control unit is notified of a desired tyre pressure or desired tyre volume. An air flow rate in a supply line to the tyre is established so that the time to pressurise the tyre to the desired tyre pressure/volume is calculable, or the time taken to pressurise the tyre to an interval pressure/volume is calculable, said interval pressure/volume being between a current tyre pressure/volume and the desired pressure/volume.