An electrohydraulic actuator assembly for use in a brake-by-wire hydraulic brake system. The electrohydraulic actuator assembly includes a pair of electrohydraulic actuator EHA units. One EHA unit provides fluid to front brakes and the other EHA unit provides fluid to rear brakes. Each EHA unit includes an electric motor, a reduction gear unit, a pair of magnetorheological clutches, and a pair of fluid pumps. The system further including an ECU that actuates the electric motor and controls engagement of the clutches to cause the fluid pump to pump brake fluid to at least one of the front and rear brakes. The system further includes a regeneration system for providing supplemental electricity to the electric motors.

A non-return valve having a valve opening spring is positioned between an unpressurized brake fluid reservoir and a brake master cylinder of a hydraulic vehicle power brake system having an externally-powered brake pressure generator. The non-return valve allows for a flow-through in the direction of the brake master cylinder and blocking against a return flow from the brake master cylinder into the brake fluid reservoir starting at a counterpressure in the brake master cylinder specified by the valve opening spring.

An electrohydraulic actuator assembly for use in a brake-by-wire hydraulic brake system. The electrohydraulic actuator assembly includes a pair of electrohydraulic actuator EHA units. One EHA unit provides fluid to front brakes and the other EHA unit provides fluid to rear brakes. Each EHA unit includes an electric motor, a reduction gear unit, a pair of magnetorheological clutches, and a pair of fluid pumps. The system further including an ECU that actuates the electric motor and controls engagement of the clutches to cause the fluid pump to pump brake fluid to at least one of the front and rear brakes. The system further includes a regeneration system for providing supplemental electricity to the electric motors.

Disclosed herein are an electric brake system and an operating method thereof. The electric brake system includes a master cylinder to discharge a pressurized medium in accordance with displacement of a brake pedal, a simulation device to provide a driver with a pedal feeling, a hydraulic pressure supply device to generate a hydraulic pressure by operating a hydraulic piston in accordance with an electrical signal output in response to the displacement of the brake pedal, and a hydraulic control unit to control a hydraulic pressure of the pressurized medium supplied to each wheel cylinder. The electric brake system may perform a normal mode, an abnormal mode, and an inspection mode.