Abstract: A pump device including a plurality of pumps having respective different operating characteristics, and a pump control device for controlling the plurality of pumps, wherein the pump control device includes a control changing portion operable in response to detection of a failure of at least one of the pumps, for changing a manner of controlling at least one of the other of the pumps such that at least a portion of the operating characteristic of each defective pump is compensated for by the changed manner of controlling each normal pump. The pump device may be used in a hydraulic pressure control system as used for a hydraulically operated braking system for an automotive vehicle.

Abstract: A braking pressure control apparatus including a first pressure source including a power-operated pressurizing device, a second pressure source operable by a manually operable brake operating member to pressurize a fluid to a pressure higher than a level corresponding to the operating force of the brake operating member, a switching device for selectively placing the braking system in a first state in which a brake cylinder is operated with the fluid pressurized by the first pressure source and a second state in which the brake cylinder is operated with the fluid pressurized by the second pressure source, and a change restricting device operable upon a switching between the first and second states, to restrict a change of the operating state of the brake operating member and a change of the brake cylinder pressure, which change take place due to the switching, or a switching control device for controlling the switching device on the basis of the running condition of a vehicle whose wheel is braked by the brak

Abstract: A brake fluid pressure control device controls brake fluid pressures through control of fluid pressure control valves operated in accordance with control signals from, for example, a computer. Signal lines for supplying control signals to control circuits controlling coils of linear valve devices for some wheels (e.g., front-left and rear-right wheels) are connected to a brake ECU by a connector, and signal lines for supplying control signals to the control circuits controlling coils of linear valve devices for other wheels (e.g., front-right and rear-left wheels) are connected to the brake ECU by a different connector. Thus, even if one of the connectors starts operating abnormally, it is possible to supply control signals via the signal lines connected by the other connector and control linear valve devices for some of the wheels (e.g., a pair of diagonally located wheels).

Abstract: A braking pressure control apparatus for a hydraulically operated brake, including a first hydraulic system having a first hydraulic pressure source power-operated to pressurize a working fluid and capable of controlling the fluid pressure, for operating the brake, a second hydraulic system having a second hydraulic pressure source operable by an operating force acting on a manually operable brake operating member, to pressurize the working fluid to a pressure higher than a level corresponding to the operating force, for operating the brake, a switching device operable to selectively establish a first state in which the brake is operated with the pressurized fluid delivered from the first hydraulic pressure source, and a second state in which the brake is operated with the pressurized fluid delivered from the second hydraulic pressure source, and a diagnosing device operable to diagnose the second hydraulic system on the basis of the fluid pressure in the second hydraulic system.

Abstract: A power source monitoring apparatus for monitoring a state of a subject power source which consists of at least one of a plurality of electric power sources in an electric system wherein a load device having at least one electrically operated load is electrically connected to the power sources, the monitoring device apparatus a detecting portion which detects a voltage and/or a current of at least one of the load device and the plurality of electric power sources, and a diagnosing device which diagnoses the subject power source for an abnormality on the basis of an output of the detecting portion, while the electric system is placed in a power supply state wherein an electric power is permitted to be supplied from only the subject power source to the load device.

Abstract: An electric brake apparatus generates an appropriate brake force without unnecessarily consuming electric power. The electric brake apparatus has a brake actuator generating a brake force. The brake actuator uses a brake motor system including a brake motor as a power source. A motor current provided to the brake motor is generated under a normal control so as to generate a brake force required for a vehicle. The motor current generated under the normal control is reduced when the brake motor is overheated or when the vehicle is stopped for a long time.

Abstract: An electric brake apparatus can positively prevent a brake motor from being excessively rotated in a reverse direction in which a braking force is cancelled. A determination is made as to whether or not the brake motor is excessively driven in the reverse direction. An operation of the brake motor is stopped when the brake motor is determined to be excessively driven in the reverse direction. Accordingly, a member of the electric brake apparatus moved by the brake motor is prevented from being excessively moved beyond a predetermined position. Thus, a part of the electric brake apparatus is prevented from being damaged due to an excessive movement of the member moved by the brake motor.

Abstract: Vehicle hydraulic braking system including a hydraulic pressure source for pressurizing a fluid according to an operation of a brake operating member, so that the pressurized fluid is supplied to at least one wheel brake cylinder for braking at least wheel of the vehicle, a pressure control valve device for regulating the pressure of the fluid to be applied to each wheel brake cylinder, the valve device having a pressure-increasing, pressure-holding and pressure-reducing states, and a reservoir for storing the fluid which has been discharged from each wheel brake cylinder through the pressure control valve device during the operation of the brake operating member, so that the fluid is returned from the reservoir to the hydraulic pressure source after the operation of the brake operating member. The reservoir has a storage capacity smaller than a maximum total amount of the fluid that can be accommodated in all of the at least one wheel brake cylinder during operation of the at least one wheel brake cylinder.

Abstract: A method of diagnosing an electrically operated brake for abnormality thereof in an automotive vehicle wherein a wheel is braked by a friction force generated by an electric motor of the brake upon an operation of a brake operating member, the method comprising the steps of: applying an abnormality checking drive signal to the electric motor to operate the electric motor while the brake operating member is placed in a non-operated position; detecting a quantity relating to an output of the electric motor while the drive signal is applied to the electric motor; and determining that the electrically operated brake is abnormal, if the detected quantity does not normally correspond to a magnitude of the abnormality checking drive signal.

Abstract: A brake stroke simulator for achieving good stroke feeling in a vehicular brake apparatus has a first piston being displaceable by receiving a master cylinder pressure, and a second piston disposed so as to form a gap between the second piston and the first piston. A plug is disposed so as to form another gap between the plug and the second piston. A first spring is disposed between the first piston and the second piston so as to urge the pistons away from each other. A second spring is provided for urging the second piston away from the plug. The brake stroke simulator is able to reduce the characteristic variations among individual products.

Abstract: Hydraulic pressure control apparatus wherein a pressure difference across a seating valve disposed in a fluid passage acts on a valve member for placing the seating valve in an open state, while an elastic member biases the valve member for placing the seating valve in a closed state, and a valve driving device operated with an electric current applied thereto generates a drive force acting on the valve member so as to open the seating valve. A control device for controlling the electric current includes a stepping controller for incrementing the amount of the electric current when the seating valve is operated from the closed state into the open state, such that an increment of the electric current decreases with an increase in the pressure difference. The hydraulic pressure control apparatus may be suitably used in a vehicle braking system, for controlling fluid pressure in wheel brake cylinder.

Abstract: A brake apparatus for an electric vehicle which maintains the regenerative energy generated in a traction motor of each of wheels to be at a maximum. A hydraulic pressure brake and a regenerative brake are provided in the same brake apparatus. The hydraulic pressure brake generates a brake torque by providing a hydraulic pressure to a wheel cylinder of each wheel of the vehicle. The regenerative brake generates a brake torque by regeneration in a traction motor for each wheel. The brake torque to be provided is calculated for each wheel. A maximum regenerative energy is calculated for each wheel. A hydraulic pressure calculating unit calculates a hydraulic pressure to be provided to the wheel cylinder of each wheel based on the brake torque and the maximum regenerative energy so that the regenerative energy generated by the traction motor of each wheel becomes a maximum.