A vehicle braking system (20) has a primary braking unit (22) with a first pressure generating unit (34) and a first reservoir (26). The vehicle braking system (20) further has a secondary braking unit (24) with a second pressure generating unit (52) and second reservoir (70). A method of operating the vehicle braking system (20) includes actuating the pressure generating unit (34) of the primary braking unit (22) thereby pressurizing a fluid at a wheel cylinder (30) to slow or stop the vehicle. The wheel cylinder (30) is depressurized in response to an electrical signal provided to an electronic control unit (100,102). The fluid is transferred from the wheel cylinder (30) to the second reservoir (70). The fluid path (PI) between the wheel cylinder (30) and the second reservoir (70) is shorter and has less fluid resistance than the fluid path (P2) between the wheel cylinder (30) and the first reservoir (26). The present invention further comprises two braking systems. The present inventions are intended for fast pressure depressurization at quick start or launch control.

The invention concerns an electronic parking brake system (2), comprising an air supply (4), a check valve (6), connected to the air supply, an electro-pneumatic control unit (8), at least one park brake actuator (10), a relay valve (12), comprising a first port (12a) connected to the check valve, a second port (12b) connected to the electro-pneumatic control unit, a third port (12c) connected to the park brake actuator and a fourth port (12d) which is in communication with the atmosphere, and an electrically actuated valve (14), which is controlled by the electro-pneumatic control unit (8) and which includes a first orifice (14a) connected to a compressed air line (16) extending between the check valve and the air supply, a second orifice (14b), a third orifice (14c) connected to the electro-pneumatic control unit (8), and preferably a vent orifice. The second orifice (14b) is connected to another compressed air line (18) extending between the check valve (6) and the first port (12a) of the relay valve (12).

A control arrangement for a vehicle motion system including a braking function, comprising motion actuators with one or more brake actuators pertaining to the braking function, a first vehicle motion management controller (VMM1) and a second vehicle motion management controller (VMM2), forming a redundant assembly to control the braking function, wherein, in riding conditions, the first vehicle motion management controller controls the brake actuators with a current nominal expected braking performance, while the second vehicle motion management controller (VMM2) is in a waiting-to-operate mode, the control arrangement comprising a hot swap functionality in which the second vehicle motion management controller (VMM2) is configured to take over control of the brake actuators from the first vehicle motion management controller, with the current nominal expected braking performance, in a short time period (SWT) less than one second, preferably less than 0.5 second, preferably less than 0.3 second, and associated control method.

An electropneumatic control module for an electronically controllable pneumatic brake system for a vehicle combination with a tractor vehicle and a trailer vehicle includes a pneumatic reservoir input, which is connectable to a compressed-air reservoir, and a trailer control unit, which has a trailer control valve unit with one or more electropneumatic valves, a trailer brake pressure port and a trailer supply pressure port. The electropneumatic control module further includes an immobilizing brake unit, which has a spring-type actuator port for at least one spring-type actuator for a tractor vehicle and an immobilizing brake valve unit with one or more electropneumatic valves, and an electronic control unit, wherein the electronic control unit is designed to, based on an electronic immobilizing signal, trigger the immobilizing brake valve unit to switch at least one valve of the immobilizing brake valve unit.

An electropneumatic control module for an electronically controllable pneumatic brake system for a vehicle combination with a tractor vehicle and a trailer vehicle includes a pneumatic reservoir input, which is connectable to a compressed-air reservoir, and a trailer control unit, which has a trailer control valve unit with one or more electropneumatic valves, a trailer brake pressure port and a trailer supply pressure port. The electropneumatic control module further includes an immobilizing brake unit, which has a spring-type actuator port for at least one spring-type actuator for a tractor vehicle and an immobilizing brake valve unit with one or more electropneumatic valves, and an electronic control unit, wherein the electronic control unit is designed to, based on an electronic immobilizing signal, trigger the immobilizing brake valve unit to switch at least one valve of the immobilizing brake valve unit.

A brake pedal unit includes a housing defining a bore formed therein. An input piston is slidably disposed in the bore. The input piston is connected to a brake pedal such that engagement of the brake pedal causes movement of the input piston within the bore of the housing of the brake pedal unit. The brake pedal unit is defined to be in an at rest position when the brake pedal in not engaged causing movement of the input piston. A primary piston is slidably disposed in the bore for pressurizing a primary chamber. A primary passageway permits fluid communication between the primary chamber and the reservoir, wherein fluid flow through the primary passageway is blocked when the brake pedal unit is in the rest position. A secondary piston is slidably disposed in the bore for pressurizing a secondary chamber. A secondary passageway permits fluid communication between the secondary chamber and the reservoir, wherein fluid flow through the secondary passageway is blocked when the brake pedal unit is in the rest position.

An electropneumatic trailer control-valve unit for a vehicle, including a storage port for coupling a store of compressed air for a trailer, a brake-pressure port, a brake-pressure pilot-control unit configured to output at least one first control pressure, a brake-pressure main-valve unit configured to receive the at least one first control pressure and to output a brake pressure at a brake-pressure port, a trailer operating-pressure port configured to receive a trailer operating pressure, and a pneumatically switched trailer protection valve with a protection-valve control port which is connected to the trailer operating-pressure port for receiving the trailer operating pressure, wherein the trailer protection valve switches from a first switching position into a second switching position if the trailer operating pressure exceeds a predetermined first threshold value, and wherein the trailer operating pressure is a supply control pressure.

A brake system includes a first functional unit having at least one first hydraulic pressure generator, which is designed to build up a hydraulic pressure at a wheel brake, and a first hydraulic fluid reservoir, from which the first hydraulic pressure generator can draw in hydraulic fluid. The brake system furthermore comprises a second functional unit having at least one second, electric hydraulic pressure generator, which is controllable in order to build up a hydraulic pressure at the wheel brake, a check valve and at least one second hydraulic fluid reservoir, having an outlet, via which the second, electric hydraulic pressure generator can draw in hydraulic fluid, and an inlet, relative to which the check valve is arranged upstream in such a way that it has a blocking effect toward the inlet in respect of a flow direction.

A brake system for selectively actuating at least one of a pair of front wheel brakes and a pair of rear wheel brakes includes a reservoir and a power transmission unit configured for selectively providing pressurized hydraulic fluid for actuating at least a selected one of the wheel brakes during a braking event. The power transmission unit includes an electric motor for selectively actuating a fluid pressurization cycle. The electric motor is a dual-wound electric motor having first and second windings. A first electronic control unit is provided for selectively controlling the first windings of the electric motor of the power transmission unit. A second electronic control unit is provided for selectively controlling the second windings of the electric motor of the power transmission unit. An isolation valve and a dump valve are associated with each wheel brake.

A brake system for selectively actuating at least one wheel brake includes a reservoir and a power transmission unit for selectively providing pressurized hydraulic fluid for actuating at least a selected one of the wheel brakes during a braking event. A first electronic control unit at least partially controls at least one of the power transmission unit and a selected one of the pair of rear brake motors. A second electronic control unit at least partially controls at least one of the power transmission unit and an other one of the pair of rear brake motors. The first electronic control unit controls at least one SAP valve, an isolation valve, and a dump valve for a selected two of the wheel brakes, and the second electronic control unit controls at least one SAP valve, an isolation valve, and a dump valve for an other two of the wheel brakes.