Abstract: The disclosure provides an anti-lock brake device including an oil pressure tank, a first piston and a second piston. The oil pressure tank has an internal space, an oil inlet and an oil outlet that are connected to one another. The first piston is slidably located in the internal space, and has a first oil channel penetrating a contact portion of the first piston and connected to the oil inlet. The second piston is slidably located in the internal space and includes a push portion, and an outer diameter of the push portion is smaller than that of the contact portion. When the second piston is in a closed position, a chamber having a first unoccupied volume is formed in the internal space. When the second piston is moved from the closed position to a depressurized position, the first volume of the chamber is increased to a second volume.

Abstract: A brake system for an automotive vehicle includes a controller for operating friction and powertrain braking subsystems so that hydraulic pressure to the friction brakes is minimized during powertrain braking, while at the same time emulating the driver-interface operating characteristics of a pure friction-braking system during all operating conditions.

Abstract: A combination secondary master cylinder and brake pedal compliance device for an automotive braking system includes a cylinder having a signal chamber, a working chamber, and a compliance chamber. Elastic devices mounted within the working chamber and compliance chamber allow the apparent compliance of the friction braking system attached to the combination device to remain at a relatively constant value notwithstanding the presence of varying amounts of powertrain braking.

Abstract: When the ABS control is executed by the ABS control portion, the vehicle brake control device calculates the first rotational speeds of the first and second motors necessary to achieve the corresponding pressure increase rates and calculates the second rotational speeds of the first and second motors as the upper limits caused by the unlocking pressure limits. Then the vehicle brake control device controls current values of the currents to be supplied to the first and second motors so that they are rotated in the rotational speeds obtained within a range from the first rotational speeds to the second rotational speeds.

Abstract: A vehicle brake control device determines a first duty factor required to achieve a stable rotational speed of motors and a second duty factor required to achieve a change rate of a target wheel cylinder pressure. The vehicle brake control device selects the larger one of the determined duty factors as a for-use motor duty factor to be used in outputting currents to the motors. Therefore, with the stable rotational speed and the change rate of the target wheel cylinder pressure, it is possible to achieve quick response to a request for braking made by a driver while suppressing the electric energy consumption of the motors.

Abstract: A brake fluid pressure controller for a vehicle includes: wheel brakes; a master cylinder for supplying pressure to a brake fluid; at least one fluid pressure passage connecting the wheel brakes with the master cylinder; a pump provided on each fluid pressure passage for intensifying the brake fluid pressure; a revolution-controllable motor for driving the pump; a motor drive control part for controlling motor revolutions; a target fluid pressure calculation part for setting a target fluid pressure of the brake fluid; a brake fluid pressure acquisition part; and a fluid pressure deviation calculation part for calculating a difference between the target fluid pressure and the brake fluid pressure. When the difference is less than a predetermined value, the motor drive control part drives the motor at a smaller number of revolutions, as compared with a case where the difference is the predetermined value or more.

Abstract: In a vehicle attitude control system of an automotive vehicle employing a pump-and-motor assembly, and a hydraulic actuator that regulates fluid pressures in wheel-brake cylinders of road wheels of the vehicle, independently of each other, a control unit is electronically connected to at least a motor of the pump-and-motor assembly and the hydraulic actuator, for executing vehicle attitude control by controlling a discharge pressure of the motor-driven pump and by controlling the fluid pressures in the wheel-brake cylinders to respective desired fluid pressures independently of each other. A processing unit of the control unit is programmed to determine a duty ratio of a drive signal of the motor, based on the desired fluid pressure of at least one of the wheel-brake cylinders.

Abstract: A pump drive motor control apparatus is applied to a motor for driving a hydraulic pump which supplies to a hydraulic circuit the brake fluid returned to a reservoir as a result of ABS control. When a motor inter-terminal voltage becomes equal to or less than a voltage threshold in a period during which a motor control signal is at a low level (supply of electricity to the motor is stopped), the control apparatus changes the motor control signal to a high level (resumes the supply of electricity) for a predetermined time, to thereby control the rotational speed of the motor. When the cause of the start of ABS control is not a demand for excessively abrupt braking, the voltage threshold is lowered to reduce the rotational speed of the motor during a predetermined period of time immediately after the start of ABS control.

Abstract: A hydraulically operated braking system including a master cylinder (12; 300: 500; 600) having a pressurizing piston (34; 322, 324; 504, 506) operatively connected to a brake operating member (10), to pressurize a fluid in a pressurizing chamber (30, 32; 302, 304; 508, 510), so that a brake cylinder (22–28), is actuated by the pressurized fluid, and an assisting device (81; 260–272; 109; 538; 612) for applying to the pressurizing piston an assisting drive force which is other than a primary drive force to be applied to the pressurizing piston on the basis of a brake operating force acting on the brake operating member. The assisting device is electrically controllable to control the assisting drive force.

Abstract: An auxiliary vehicle hydraulic pressure source device includes a hydraulic pressure pump pressurizing and discharging fluid, an accumulator accumulating fluid pressurized and discharged by the hydraulic pressure pump, a hydraulic pressure detector continuously detecting the accumulator hydraulic pressure, and a controller controlling operation of the hydraulic pressure pump based on a comparison of the detection result of the hydraulic pressure detector with a predetermined target pressure.

Abstract: There are provided a master cylinder M and proportional pressure intensification valves V1, V2 for each drawing a boosting hydraulic pressure in proportion to an output hydraulic pressure outputted from the master cylinder M from a source of hydraulic pressure S into a hydraulic pressure boosting chamber 30, wherein one of pairs of front wheel brakes Bfa, Bfb and rear wheel brakes Bra, Brb connects to output ports 11, 12 of the master cylinder M, and the other pair connects to the hydraulic pressure boosting chambers 30 of the respective proportional pressure intensification valves V1, V2. Accordingly, it is possible to provide a vehicle braking system comprising proportional pressure intensification valves for generating a boosted hydraulic pressure intensified in proportion to an output hydraulic pressure outputted from a master cylinder without any increase in unsprung load of the vehicle.

Abstract: In a method for the adaptive control of the hydraulic pump of a brake system containing low pressure accumulator (NDS1,2) which take up the pressure fluid discharged in the case of control from the wheel brakes and which are evacuated by the hydraulic pump (HP), first the brake pressure pattern (pR) is determined for each individual wheel with the aid of a wheel pressure model. Then a volume model (VM1,2) is formed on the basis of the wheel pressure model for each individual brake circuit, which volume model indicates, by way of approximation, the filling level of the low pressure accumulators (NDS1,2). The maximum filling level (MaxV) and the control frequency or the time interval (T) between two successive brake pressure decreasing phases (Ph2) are determined. The delivery capacity of the hydraulic pump (HP) is so dimensioned that the time interval (T) between two successive brake pressure decreasing phases (Ph2) is just adequate for completely evacuating the low pressure accumulators (NDS1,2).

Abstract: A brake force control apparatus having a pump for pumping up brake fluid from a fluid pressure passage connecting a master cylinder and a wheel cylinder is provided which can accurately detect an amount of brake operation intended by a driver during execution of a brake assist control. The brake assist control is achieved by supplying the brake fluid delivered by the pump to the wheel cylinder when an emergency brake operation is performed by a driver. The brake force control apparatus has a control signal generator and a fluid pressure controller. The control signal generator generates a control signal by compensating a decrease generated in the output signal when the pump pumps up the brake fluid from the fluid pressure passage. The fluid pressure controller performs the brake assist control by using the control signal.