An electric booster for a vehicle includes a housing having a cylinder structure capable of supporting a hydraulic pressure formed therein; a screw bolt installed in the housing; a screw nut screwed to the screw bolt; a gear unit configured to transfer a rotational force of a motor to the screw nut; a rotation preventing unit coupled with the screw bolt, and configured to prevent rotation of the screw bolt by being brought into contact with the housing; and a piston moved by being pressed by the screw bolt, and configured to form a hydraulic pressure in the housing.

An electric booster including an input member that is advanceably/retractably moved according to a brake pedal operation. An electric motor of an electric actuator advanceably/retractably moves a power piston. A master pressure control unit sets a target movement amount of the power piston according to an amount of a movement of the input member that is caused by the brake pedal, and controls the electric motor to move the power piston so as to achieve the target movement amount, thereby causing a brake hydraulic pressure to be generated in a master cylinder. The master pressure control unit includes a reaction force generation portion, which changes a characteristic of a hydraulic reaction force applied to the brake pedal. The reaction force generation portion corrects the target movement amount of the power piston according to a temporal change in the movement amount of the input member.

A method of calibrating a solenoid actuated valve includes: providing a brake system including a fluid pressure source: providing a valve having a solenoid, and wherein the valve is in fluid communication with the fluid pressure source; operating the fluid pressure source to provide a constant flow of fluid to the valve; energizing the solenoid of the valve with a constant current such that fluid flows through the valve; measuring the pressure of the fluid flowing at the valve; adjusting the current sent to the solenoid until a predetermined pressure has been obtained; storing a nominal current value of the current required to obtain the predetermined pressure; and calibrating the valve by adding a correction offset factor to the nominal current value for future actuation of the solenoid of the valve.

A brake controller according to the present disclosure that changes an effect correlation value correlating to an effect of braking in a first braking system provided in a vehicle in accordance with a vehicle condition of the vehicle includes a control part generating a braking force by at least one of the first braking system and a second braking system different from the first braking system in a case where the vehicle condition is a first condition based on a braking distribution ratio different from that in a case where the vehicle condition is a second condition and a setting part setting the effect correlation values so as to be different from each other in the case where the vehicle condition is the first condition and in the case where the vehicle condition is the second condition.

Systems and methods for providing open loop motor control for an electromechanical brake when closed loop motor control fails. The method includes determining, with an electronic controller, whether a rotor position sensor or a current sensor is not operating correctly, generating, with the electronic controller, a generated control signal for controlling a permanent magnet synchronous machine, and activating, with the electronic controller, the permanent magnet synchronous machine using the generated control signal to generate a stator magnetic field to operate the rotor of the permanent magnet synchronous machine of the electromechanical brake.

A method of controlling the fluid pressure at wheel brakes of a brake system, the method comprising: (a) providing a brake system capable of delivering fluid pressure to the wheel brakes during an autonomous braking event, and wherein the brake system includes a brake pedal and sensor for sensing a driver's braking intent when applying force to the brake pedal; (b) controlling the fluid pressure at the wheel brakes at a predetermined pressure during an autonomous braking event, wherein the sensor detects no depression of the brake pedal; (c) cancelling the autonomous braking event when the sensor detects depression of the brake pedal; and (d) subsequently to step (c), the brake system enters into a handoff procedure to maintain the predetermined pressure at the wheel brakes after the sensor senses the brake pedal being depressed when a requested pressure by the driver is less than the predetermined pressure.

The vehicular brake device includes a determination unit, a ratio setting unit, and the control unit. The determination unit determines the operating condition of a vehicular brake device. The ratio setting unit sets, on the basis of the result of determination by the determination unit, a first ratio which is the ratio of a wheel pressure generated by a piston drive unit to a target wheel pressure, and a second ratio which is the ratio of a wheel pressure generated by a hydraulic pressure adjusting unit to the target wheel pressure. The control unit controls the piston drive unit and the hydraulic pressure adjusting unit on the basis of the first ratio and the second ratio.

Systems and methods for providing open loop motor control for an electromechanical brake when closed loop motor control fails. The method includes determining, with an electronic controller, whether a rotor position sensor or a current sensor is not operating correctly, generating, with the electronic controller, a generated control signal for controlling a permanent magnet synchronous machine, and activating, with the electronic controller, the permanent magnet synchronous machine using the generated control signal to generate a stator magnetic field to operate the rotor of the permanent magnet synchronous machine of the electromechanical brake.

A control device is applied to a friction brake device of a vehicle. The friction brake device produces a friction brake force in the vehicle by starting driving of an electric motor. The control device includes a motor control unit configured to control the electric motor. The control device includes an acquisition unit configured to acquire an index value corresponding to a magnitude of a target value of the friction brake force. A value for determining a magnitude of the index value is set as a limit determination value. The motor control unit limits an increase speed of the number of rotations of the electric motor if the index value is equal to or less than the limit determination value, and releases the limit if the index value exceeds the limit determination value.

An electric booster for a vehicle includes a housing having a cylinder structure capable of supporting a hydraulic pressure formed therein; a screw bolt installed in the housing; a screw nut screwed to the screw bolt; a gear unit configured to transfer a rotational force of a motor to the screw nut; a rotation preventing unit coupled with the screw bolt, and configured to prevent rotation of the screw bolt by being brought into contact with the housing; and a piston moved by being pressed by the screw bolt, and configured to form a hydraulic pressure in the housing.