To check an electrohydraulic power vehicle brake system of a passenger car traveling autonomously on public roads for air in the brake fluid, the method provides for a consecutive generation of a brake pressure using a first power brake-pressure generator and a redundant, second power brake-pressure generator. The brake pressure is intermittently lowered to ambient pressure. In the method, a comparison of the brake fluid volumes required for generating the brake pressure is provided. If the brake fluid volume required for generating the brake pressure using the second power brake-pressure generator is greater, then the presence of air in a brake fluid of the vehicle brake system is inferred.

To check an electrohydraulic power vehicle brake system of a passenger car traveling autonomously on public roads for air in the brake fluid, the method provides for a consecutive generation of a brake pressure using a first power brake-pressure generator and a redundant, second power brake-pressure generator. The brake pressure is intermittently lowered to ambient pressure. In the method, a comparison of the brake fluid volumes required for generating the brake pressure is provided. If the brake fluid volume required for generating the brake pressure using the second power brake-pressure generator is greater, then the presence of air in a brake fluid of the vehicle brake system is inferred.

Provided is an electronic brake system. The electronic brake system includes: a reservoir in which a pressurized medium is stored; an integrated master cylinder including a master chamber and a simulation chamber; a reservoir flow path to communicate the integrated master cylinder and the reservoir; a hydraulic pressure supply device configured to generate a hydraulic pressure by operating a hydraulic piston according to an electrical signal output in response to a displacement of a brake pedal, and including a first pressure chamber provided on one side of the hydraulic piston accommodated to be movable in a cylinder block and connected to one or more wheel cylinders, and a second pressure chamber provided on another side of the hydraulic piston and connected to the one or more wheel cylinders; a hydraulic control unit having a first hydraulic circuit configured to control a hydraulic pressure transferred to two wheel cylinders and a second hydraulic circuit configured to control a hydraulic pressure transferred to other two wheel cylinders; and an electronic control unit configured to control valves based on hydraulic pressure information and displacement information of the brake pedal.

Provided is an electronic brake system. The electronic brake system includes: a reservoir in which a pressurized medium is stored; an integrated master cylinder including a master chamber and a simulation chamber; a reservoir flow path to communicate the integrated master cylinder and the reservoir; a hydraulic pressure supply device configured to generate a hydraulic pressure by operating a hydraulic piston according to an electrical signal output in response to a displacement of a brake pedal, and including a first pressure chamber provided on one side of the hydraulic piston accommodated to be movable in a cylinder block and connected to one or more wheel cylinders, and a second pressure chamber provided on another side of the hydraulic piston and connected to the one or more wheel cylinders; a hydraulic control unit having a first hydraulic circuit configured to control a hydraulic pressure transferred to two wheel cylinders and a second hydraulic circuit configured to control a hydraulic pressure transferred to other two wheel cylinders; and an electronic control unit configured to control valves based on hydraulic pressure information and displacement information of the brake pedal.

A vehicle braking device includes a first supply unit supplying fluid to main flow channels connected to wheel cylinders of a vehicle, a differential solenoid valve provided on the main flow channels and generating a differential pressure across the differential solenoid valve, a second supply unit supplying fluid to the wheel cylinders by drawing at least some fluid supplied from the first supply unit through branch flow channels branching off from the main flow channels upstream of the differential solenoid valve, and a setting unit setting a supply amount of fluid supplied from the first supply unit in accordance with a draw amount of fluid drawn by the second supply unit.

The present invention relates to an electronic parking brake device for a vehicle, in particular a utility vehicle. As a function of at least one operating state of a towing vehicle parking brake supply line and/or a trailer parking brake supply line, a towing vehicle parking brake control valve is activatable by means of a control unit in such a way that a towing vehicle parking brake supply line can be deaerated or aerated by the towing vehicle parking brake control valve. By manually actuating a trailer parking brake control element, a trailer parking brake control valve is activatable by means of the control unit in such a way that a trailer parking brake supply line can be deaerated or aerated by the trailer parking brake control valve. The present invention also relates to a method for operating the above electronic parking brake device for a vehicle.

The present invention relates to an electronic parking brake device for a vehicle, in particular a utility vehicle. As a function of at least one operating state of a towing vehicle parking brake supply line and/or a trailer parking brake supply line, a towing vehicle parking brake control valve is activatable by means of a control unit in such a way that a towing vehicle parking brake supply line can be deaerated or aerated by the towing vehicle parking brake control valve. By manually actuating a trailer parking brake control element, a trailer parking brake control valve is activatable by means of the control unit in such a way that a trailer parking brake supply line can be deaerated or aerated by the trailer parking brake control valve. The present invention also relates to a method for operating the above electronic parking brake device for a vehicle.

A brake system for a motor vehicle comprises a normally closed circuit separation valve such that the system is configured to operate in 1) in a by-wire mode when the circuit separation valve is open, such that pressure only from a pressure chamber of a linear actuator is delivered to both first and second pairs of wheel brakes, and 2) in a circuit separation mode with the circuit separation valve in the normally closed position, such that pressure from a tandem master cylinder is delivered only to the first pair of wheel brakes, and such that pressure from the pressure chamber of the linear actuator is concurrently delivered only to the second pair of wheel brakes. The system can provide braking pressure even in the event of a by-wire braking module leak that causes inoperability of an ECU.

A brake system for a motor vehicle comprises a normally closed circuit separation valve such that the system is configured to operate in 1) in a by-wire mode when the circuit separation valve is open, such that pressure only from a pressure chamber of a linear actuator is delivered to both first and second pairs of wheel brakes, and 2) in a circuit separation mode with the circuit separation valve in the normally closed position, such that pressure from a tandem master cylinder is delivered only to the first pair of wheel brakes, and such that pressure from the pressure chamber of the linear actuator is concurrently delivered only to the second pair of wheel brakes. The system can provide braking pressure even in the event of a by-wire braking module leak that causes inoperability of an ECU.

Disclosed herein an electronic brake system includes a first block in which a mechanical unit operated mechanically in association with a brake pedal is disposed; a second block in which an electrical unit electronically operated and controlled by an electronic control unit is disposed; and a connection line configured to hydraulically connect the first block and the second block, and the first block and the second block are installed at positions spaced apart in a vehicle so that mountability of the brake system and the degree of freedom in design of the vehicle may be improved.