Monitoring a brake that includes first and second braking surfaces and a magnetizing device that, in response to the electric current supplied to them, are arranged to generate a magnetic field that is arranged to move the braking surfaces from a closed state, in which the braking surfaces are connected to each other, to an open state, in which the braking surfaces are separated from each other. Determining the electric current of the brake as the braking surfaces begin to move from the closed state to the open state, determining the maximum electric current of the magnetizing device of the brake in the open state, determining the condition of the brake as a current ratio from the electric current measured as the braking surfaces start to move to the maximum electric current.

A vehicle engine activation control system includes a starter connected to a battery; an idle stop control unit configured to automatically stop an engine and automatically reactivate the engine by the starter; an input unit configured to generate an operation request in response to input from a driver; an electric parking brake device including an electric motor connected to the battery, wherein the electric motor starts driving in response to the operation request; and a mediating unit configured to prohibit the reactivation of the engine by the idle stop control unit, when the electric motor is in a driving state in response to a predetermined operation request.

An electric linear motion actuator includes an electric motor, a motion conversion mechanism for converting the torque of the electric motor to the linear driving force of an outer ring member, a load sensor, and a motor control device. The motor control device is configured to control the electric current applied to the electric motor such that the torque of the electric motor increases until the pressing force detected by the load sensor exceeds a target value, and then the torque of the electric motor decreases until the pressing force detected by the load sensor reaches the target value.

A vehicle braking system includes a first wheel cylinder, a second wheel cylinder, a master cylinder including a first master cylinder chamber in fluid communication with the first wheel cylinder via a first circuit and a second master cylinder chamber in fluid communication with the second wheel cylinder via a second circuit, and an electronically controlled pressure generating unit separate from the master cylinder. The vehicle braking system is operable to provide braking in a first configuration in which the electronically controlled pressure generating unit pressurizes fluid, through the master cylinder, in the first circuit, to the first wheel cylinder. In the first configuration, the electronically controlled pressure generating unit pressurizes fluid in the second circuit to the second wheel cylinder, bypassing the master cylinder.

An electric brake for a wheel rotor having a brake pad includes a housing with a passage. A piston assembly in the passage includes a spindle and a piston. The spindle is rotatable to cause the piston to move axially relative to the brake pad. A drive assembly includes a motor. A gear train is connected to the motor and the spindle. A coupling mechanism is coupled to the gear train and has a first condition enabling torque transmission from the motor to the spindle to axially move the piston to apply braking force to the brake pad. The coupling mechanism has a second condition disabling torque transmission from the motor to the spindle is prevented which permits the piston to retract and reduce the braking force on the brake pad without stopping or reversing the motor.

A brake system for hydraulically actuating a pair of front wheel brakes and a pair of rear wheel brakes includes master cylinder fluidly connected to a reservoir and operable to provide a brake signal responsive to actuation of a brake pedal connected thereto. The master cylinder is selectively operable in a manual push-through mode. First and second power transmission units are in fluid communication with the reservoir and selected front and rear wheel brakes. An electronic control unit selectively controls at least one of the first and second power transmission units. First and second two-position three-way valves are each hydraulically connected with a respective power transmission unit, the master cylinder, and a respective front wheel brake. The first and second two-position three-way valves are configured to place the master cylinder in push-through fluid-supplying connection with at least a corresponding one of the pair of front wheel brakes.

A method of applying an automated parking brake of a motor vehicle includes at least two phases. In a first preceding phase, no clamping force is produced by the parking brake. In a second following phase, a clamping force is produced by the parking brake via a controllable parking brake actuator configured to produce the clamping force. The method further includes detecting a transition from the first phase to the second phase based on a temporal progression of a specific parameter of a control of the parking brake actuator. A control unit is configured to perform according to the method, and a parking brake is configured to perform according to the method.

The invention relates to a ball screw including a spindle nut arranged on a lead screw, and balls, which roll on ball grooves of the spindle nut and of the lead screw, and a circumferential stop on the screw side and a circumferential stop on the nut side, the spindle nut being arranged in a sleeve surrounding the ball nut, the sleeve is formed from sheet metal by shaping and the nut-side circumferential stop is formed integrally on the sleeve.

A brake control device capable of preventing a braking force from being excessive when information cannot be transmitted between a first control unit configured to control operation of a boost mechanism and a second control unit configured to control operation of a hydraulic control mechanism. When a second ECU (32) cannot transmit information to a first ECU (26) due to a disconnection of a signal line (27), the second ECU carries out backup control of detecting a braking operation amount of a driver based on signal input from hydraulic pressure sensors (29), and operating a hydraulic pressure supply device (30) based on the detected braking operation amount, to thereby pressurize insides of wheel cylinders. In this case, the second ECU decreases a pressurization amount of a pressure inside the wheel cylinders when a pressure of a master cylinder (8) exceeds a predetermined value (PM0) during the backup control.

A brake control device capable of preventing a braking force from being excessive when information cannot be transmitted between a first control unit configured to control operation of a boost mechanism and a second control unit configured to control operation of a hydraulic control mechanism. When a second ECU (32) cannot transmit information to a first ECU (26) due to a disconnection of a signal line (27), the second ECU carries out backup control of detecting a braking operation amount of a driver based on signal input from hydraulic pressure sensors (29), and operating a hydraulic pressure supply device (30) based on the detected braking operation amount, to thereby pressurize insides of wheel cylinders. In this case, the second ECU decreases a pressurization amount of a pressure inside the wheel cylinders when a pressure of a master cylinder (8) exceeds a predetermined value (PM0) during the backup control.