Abstract: Various antilock braking systems, devices, and methods using sensorized brake pads are disclosed. In some embodiments, the present disclosure provides a method for improving the performance of an antilock braking (ABS) and anti-slip regulation (ASR) system of a vehicle. The method can include detecting the actual value of the coefficient of friction (e.g., between a tire and the ground), updating the coefficient of friction during braking using the braking torque data derived from at least one braking pad of each wheel, and adjusting brake force. For example, the brake force can be adjusted as a function of and/or to be approximately equal to the value of the actual tire-road friction during braking.

Abstract: The disclosure relates to assessing and responding to wheel slippage and estimating road friction for a road surface. For instance, a vehicle may be controlled in an autonomous driving mode in order to follow a trajectory. A wheel of the vehicle may be determined to be slipping such that the vehicle has limited steering control. In response to determining that the wheel is slipping, steering of one or more wheels may be controlled in order to orient the one or more wheels towards the trajectory in order to allow the vehicle to proceed towards the trajectory when the wheel is no longer slipping. In addition, the road friction may be estimated based on the determination that the wheel is slipping. The vehicle may be controlled in the autonomous driving mode based on the estimated road friction.

Abstract: A method for adapting a driving behavior of a vehicle or of a vehicle combination based on vehicle parameters, in particular by a control unit. In the method, static vehicle parameters are received, preferably prior to starting the drive, measuring data being collected and received during at least one initiated driving maneuver, the measuring data received during the at least one initiated driving maneuver being evaluated for ascertaining at least one dynamic vehicle parameter, and the static vehicle parameters and/or ascertained dynamic vehicle parameters being transmitted to a vehicle control unit for the vehicle-specific adaptation of a driving behavior. A control unit, a computer program, and a machine-readable memory medium are also described.

Abstract: A method is provided for detecting a fault condition in a hydraulic brake system of a vehicle having a first hydraulic brake circuit and a second hydraulic brake circuit. A correlation ratio is determined between a measured pressure and the actual vehicle acceleration. A first wheel velocity differential is determined and a second wheel velocity differential is determined. A weighting value is selected in response to determining whether the correlation ratio is within the predetermined range and whether the first wheel velocity differential and the second wheel velocity differential are opposite signs. The selected weighting value is added to a fault counter. A determination is made whether the fault counter is equal to or greater than a predetermined threshold. A fault condition is detected in response to the fault counter greater than or equal to the first predetermined threshold.

Abstract: The invention relates to a method for determining a driving characteristic of an analogized or analog-controlled hydraulic valve of a brake system for motor vehicles, comprising hydraulically operatable wheel brakes, in which a brake pressure (pDBE), which is generated with the aid of an electrically controllable, electric-motor-driven (110, 35) driven pressure supply device (101, 5), is conducted to a wheel brake (105a, 105b; 8-11) via an inlet valve (102a, 102b; 6a-d) and can be conducted in particular via an outlet valve (103a, 103b, 7a-d) from the wheel brake into a pressure medium container (104, 4).

Abstract: A state display section of a work vehicle is configured to display whether an electricity storage apparatus is in an electricity charging or discharging state. A state determination unit is configured to determine the state to be displayed on the state display section on the basis of a parameter corresponding to electricity supplied to or discharged from the electricity storage apparatus. The state determination unit is configured to change a threshold for a parameter for determining if the state to be displayed on the state display section is to be set to the charging state (discharging state) based on whether or not the state displayed on the state display section most recently is the charging state (discharging state). Until a predetermined first time period elapses, the state determination section is configured to determine the state after the change as the state to be displayed on the state display section.

Abstract: A vehicle height adjustment apparatus adjusts a vehicle height by changing a front distance that is a distance in a longitudinal direction of the front fork between a body of a vehicle and a front wheel of the vehicle, and by changing a rear distance that is a distance in a longitudinal direction of the rear suspension between the body of the vehicle and a rear wheel of the vehicle. In this apparatus, the posture of the vehicle body is not affected even when the vehicle height is adjusted (i.e., raised), providing the vehicle with further stability during driving.

Abstract: A hydraulic system for an aircraft includes a brake operation device, a pressure supply, a reservoir, a shut-off valve, and a wheel brake. The shut-off valve is in fluid communication with and is disposed between the pressure supply and the brake valve. The shut-off valve can include a poppet, a first valve seat and a second valve seat. Movement of the poppet is controlled by operation of the brake operation device. The poppet is movable between a first position where the poppet acts against the first valve seat and a second position where the poppet acts against the second valve seat. In the first position, fluid flow is blocked between the pressure supply and the brake valve through the shut-off valve. In the second position, fluid flow is allowed between the pressure supply and the brake valve through the shut-off valve. The wheel brake is in fluid communication with and downstream from the shut-off valve.

Abstract: A brake system, and a method for operating a brake system of a vehicle. To reduce a braking force, brake fluid is able to be discharged from the braking device via a cross-section adjusting member which connects a delivery device to the braking device, in a controlled and/or regulated manner, into an intermediate reservoir and is delivered to the main brake cylinder using the delivery device. The discharge of the brake fluid from the braking device of the brake system takes place, at least at times, at a discharge volume flow that is greater than the maximum delivery volume flow of the delivery device, and when a certain operating state of the braking system occurs, the discharge volume flow is reduced.

Abstract: An actuator for a brake system of a rail vehicle has a set-value detection unit that outputs a set value or a set value corrected by a reducing signal of an anti-skid control device for a decelerating force or a decelerating torque to a set-value control device. The latter controls the set value to a first output set value. A switch-over device connects an output of the set-value control device to a input of a set-value/force conversion device in a first switching position. In a second switching position, the set-value/force conversion device receives the signal from a fall-back unit. Braking devices convert an actual value of the force into an actual value of the decelerating force or decelerating torque. When impermissible deviations from a fast braking set value in a fast-braking operation are found, the switch-over device switches from the first to the second switching position.

Abstract: A method for controlling a hydraulic braking system of a motor vehicle is provided. The method includes determining the vehicle speed and comparing the vehicle speed with a predefinable critical vehicle speed. If the vehicle speed lies below the critical vehicle speed, the method includes determining a required brake pressure or a brake pressure present in the braking system and comparing the brake pressure with a predefinable critical brake pressure. The method includes if the brake pressure lies below the critical brake pressure, blocking the buildup of a brake pressure in wheel brakes used for braking vehicle wheels of a vehicle rear axle.

Abstract: A deceleration of a vehicle is determined based on one or more wheel speeds of the vehicle. A brake pressure of the vehicle is determined. A model of a relationship of the deceleration and the brake pressure is produced. At least one of a vehicle load and a vehicle weight is determined by using the model. The brake pressure is adapted to at least one of the determined vehicle load and the vehicle weight.

Abstract: A vehicle braking force control device which, at a normal time, performs antilock brake control when the slip ratio of a wheel has become equal to or greater than a predetermined threshold. The control device acquires from the engine control unit an accelerator pedal position signal corresponding to an accelerator pedal position, a clutch connection signal corresponding to a state of connection of a clutch, and a power transmission signal corresponding to a state of power transmission of a transmission. When engine braking is large on the basis of the accelerator pedal position signal, the clutch connection signal, and the power transmission signal, the vehicle braking force control device changes the predetermined threshold value to an offset threshold value that makes it harder to perform the antilock brake control than at the normal time.

Abstract: A system and a method are provided for controlling a foundation brake of a vehicle having at least one foundation brake device, wherein the usability of the foundation brake is limited to a predetermined total application-time of the foundation brake within a predetermined time interval.

Abstract: A system for determining a safe maximum speed of an vehicle has a processor and a global positioning system receiver in communication with the processor. The processor is configured to determine a grade and distance to an end of an upcoming or a current road segment the vehicle is traveling on based on the global positioning system information received from the global positioning system receiver. The processor is further configured to determine the safe maximum speed of the vehicle based on the distance to the end and pitch of the grade of the upcoming or current road segment the vehicle is traveling on and the braking efficiency of the vehicle.

Abstract: In a brake system, when setting a control origin position for a resolver for detecting a moved position of a booster piston, communication between a master cylinder and wheel cylinders is interrupted by cut valves. Thereafter, the booster piston is moved forward by an electric actuator in a direction in which a hydraulic pressure is generated so that a position detected by the resolver upon detection of generation of the hydraulic pressure by a hydraulic pressure sensor (position at a time of generation of hydraulic pressure) is obtained. A position obtained by moving backward the position at the time of generation of hydraulic pressure by a predetermined amount is set as the control origin position.

Abstract: The work vehicle includes a braking device, a lubricant feeding section, and a controlling section. The controlling section configured to execute a first control in which an amount of the lubricant fed to the braking device is controlled based on a temperature of a rotating member of the braking device. The controlling section sets the amount of the lubricant to a predetermined first feed amount when the braking device is in a braking state, calculates the temperature of the rotating member, and makes a decision in the first control, based on the calculated temperature of the rotating member, to change the amount of the lubricant from the first feed amount to a second feed amount, which is smaller than the first feed amount, when the braking device is switched from the braking state to a non-braking state.

Abstract: A deceleration system may be used for decreasing a speed of a vehicle having a plurality of wheels. The deceleration system may include a brake command receiving device configured to receive a brake command for decelerating the vehicle, a brake command sensor configured to determine a brake magnitude and a brake rate based on the brake command, a control device configured to generate a plurality of electronic brake signals based on the brake magnitude and the brake rate, and a plurality of braking devices, each of which is configured to receive one of the plurality of electronic brake signals, convert the respective electronic brake signal to a mechanical brake force, and impart the mechanical brake force to at least one of a rotor or a drum of the respective wheel, thereby causing a deceleration of the vehicle.

Abstract: Methods, systems, and vehicles are provided for calibrating a braking system of a vehicle. The braking system has an electric motor, a pump, and a hydraulic accumulator. A speed of the vehicle is obtained, and a pressure within the hydraulic accumulator is measured. The pump is operated via an electric motor to provide hydraulic pressure to the hydraulic accumulator based on the speed of the vehicle and the measure of pressure of the hydraulic accumulator.

Abstract: A brake control apparatus includes: a master cylinder; a wheel cylinder; a hydraulic pressure source; a control valve arranged to increase or reduce the pressure of the wheel cylinder; an outside gate valve arranged to connect or disconnect between the master cylinder and the wheel cylinder; a brake operation sensing section configured to sense a driver's brake operation; and a control unit configured to control the hydraulic pressure source, the control valve, and the outside gate valve, to perform an automatic-brake pressure-increasing control to control the outside gate valve in a valve closing direction, to drive the hydraulic pressure source, and thereby to increase the pressure of the wheel cylinder in accordance with a vehicle condition, and to increase a driving quantity of the hydraulic pressure source when the brake operation is sensed during the automatic-brake pressure-increasing control.

Abstract: A brake force maintain control device for a vehicle determines whether the vehicle is in a rapidly-pressed state. The rapidly-pressed state is a state in which the brake pedal of the vehicle has been further pressed rapidly. While the vehicle is in the rapidly-pressed state, the brake force maintain control device allows the brake force maintain control to start if a condition for starting the brake force maintain control is satisfied. Therefore, it is possible to prevent the brake force maintain control from being needlessly executed even though the driver does not have an intention of executing it.

Abstract: In a hybrid vehicle 20, when an ECO switch 88 is “on” when a brake demand operation is performed by a driver, a target regeneration distribution rate d is set using an ECO mode regeneration distribution rate setting map that gives priority to energy efficiency in comparison to a normal regeneration distribution rate setting map that is used when the ECO switch 88 is “off” and a braking force demand BF* that is based on the brake demand operation of the driver (S150), and a motor MG2 and a brake unit 90 are controlled so that the braking force demand BF* is obtained based on the target regeneration distribution rate d (S160 to S230).

Abstract: A vehicle control apparatus controlling a driving force or a braking force to be applied to a vehicle and conducting a vehicle control based on wheel speeds includes a detecting means detecting the wheel speed of each wheel provided at the vehicle, a storing means storing a predetermined valid wheel speed for each wheel, a determining means determining whether a difference between the detected wheel speed and a maximum wheel speed of the wheel speeds lies in a predetermined range, and an updating means updating the valid wheel speed based on the detected wheel speed of the wheel, when the detected wheel speed is lower than the predetermined valid wheel speed which is currently stored, in case that a result determined by the determining means is positive.

Abstract: A mechanism for reducing brake noise during braking of a vehicle. The mechanism includes controllers and methods that “hold” a currently applied braking torque rather than applying the operator-requested braking torque when a vehicle is traveling at a low speed and the operator-requested braking torque is within a predetermined range. The controllers and methods “release” the previously “held” braking torque and apply the operator-requested braking torque once the operator-requested braking torque is outside the predetermined range.

Abstract: A brake fill effect minimization function for preventing or reducing brake controller windup during a brake fill condition or the like that may commonly occur in hydraulic or electromechanical brake systems, particularly during initial application of the brakes or during anti-skid conditions. The function temporarily reduces error input to the brake controller during a perceived brake fill condition (hydraulic brakes) or running clearance condition (electromechanical brakes) thereby facilitating smooth application of the brakes during initial braking and/or under anti-skid conditions.

Abstract: A brake system for a vehicle having a sensor device for providing a first and second sensor signal, a first and a second brake control device, which are directly connected to the sensor device and to provide a corresponding control signal for the first and/or second sensor signal, and a first and a second signal line for transmitting the control signal, the first signal line directly connecting the first brake control device to a first and second wheel actuator device and the second signal line directly connecting the second brake control device to a third and fourth wheel actuator device, the four wheel actuator devices exerting a braking torque corresponding to the control signal on the associated wheel, and the first wheel actuator device being directly connected to the second brake control device and/or the sensor device. A method for operating a brake system for a vehicle is also provided.

Abstract: Methods and systems are provided for improving brake performance, including extending the life of carbon brakes on aircraft. One embodiment of the method comprises measuring the speed of the aircraft and the intensity of braking and comparing these to predetermined maximum values for each. If the values are both lower than the maximum values, one or more of the brakes are selectively disabled.

Abstract: A method of reducing wheel slip and wheel locking in an electric traction vehicle includes receiving in a first controller a first signal value representative of a first amount of torque to be applied to at least one wheel of the electric traction vehicle by a motor coupled to the wheel and to the first controller, and a second signal value representative of a reference speed of the electric traction vehicle. The first and second signal values are generated by a second controller in communication with the first controller. The method also includes receiving in the first controller a third signal value representative of a speed of the at least one wheel, determining in the first controller a torque output signal using the first, second, and third signal values; and transmitting the torque output signal from the first controller to the motor.

Abstract: In brake control system and method for an automotive vehicle, a vehicle body deceleration increment correction quantity is set to zero during a start of braking, the vehicle body deceleration increment correction quantity is set to be gradually larger along with at least one of a decrease in the traveling velocity of the vehicle and an increase in a braking passage time in a first region in which a traveling velocity of the vehicle is equal to or higher than a first predetermined traveling velocity, and the vehicle body deceleration increment correction quantity is set to a substantially constant value in a second region in which the traveling velocity of the vehicle is lower than the first predetermined traveling velocity.

Abstract: This apparatus is applied to a vehicle brake apparatus provided with a hydraulic booster operated by utilizing an accumulator hydraulic pressure that is adjusted to a predetermined high pressure (not less than a lower limit value) by a drive control of a hydraulic pump. This apparatus executes an automatic pressurization control by controlling plural solenoid valves with the use of the accumulator hydraulic pressure. The increasing slope of the brake hydraulic pressure during the automatic pressurization control is determined on the basis of the vehicle motion state. The increasing slope is restricted to be not more than a predetermined restriction value, in the case where the accumulator hydraulic pressure at the time of starting the automatic pressurization control is less than “a reference hydraulic pressure that is greater than a minimum value of the accumulator hydraulic pressure necessary for assisting the brake operation by the hydraulic booster and smaller than the lower limit value”.

Abstract: The adaptive brake application and initial skid detection system allows rapid brake application and prevents deep initial skids. Brake pressure is compared with a predetermined threshold brake pressure. Wheel velocity error signals are also generated to indicated the difference between the wheel velocity and a reference velocity signal. A pressure bias modulator integrator responsive to brake pressure signals adjusts the wheel velocity error signals to provide an anti-skid control signal. The pressure bias modulator integrator can also be initialized to the value of the measured brake pressure when the wheel velocity error signals indicate the beginning of a skid. Brake pressure difference signals are generated to indicate the difference between brake pressure and a commanded brake pressure, and an adjusted brake pressure error signal is generated in response to the brake pressure difference signals.

Abstract: This apparatus is applied to a vehicle brake apparatus provided with a hydraulic booster operated by utilizing an accumulator hydraulic pressure that is adjusted to a predetermined high pressure (not less than a lower limit value) by a drive control of a hydraulic pump. This apparatus executes an automatic pressurization control by controlling plural solenoid valves with the use of the accumulator hydraulic pressure. The increasing slope of the brake hydraulic pressure during the automatic pressurization control is determined on the basis of the vehicle motion state. The increasing slope is restricted to be not more than a predetermined restriction value, in the case where the accumulator hydraulic pressure at the time of starting the automatic pressurization control is less than “a reference hydraulic pressure that is greater than a minimum value of the accumulator hydraulic pressure necessary for assisting the brake operation by the hydraulic booster and smaller than the lower limit value”.

Abstract: System for detecting stability/instability of behavior of a motor vehicle upon occurrence of tire slip or lock. State of the motor vehicle is determined on the basis of an alignment torque (Ta) applied from a road and a side slip angle (?). By taking advantage of such torque/slip-angle characteristic that although the alignment torque is proportional to a side slip angle when the latter is small, the alignment torque becomes smaller as the side slip angle increases, a normal value is determined from a straight line slope and the side slip angle in a region where the latter is small. Unstable behavior of the motor vehicle is determined when deviation of actual measured value from the normal value increases. Further, unstable state is determined when the slope of the alignment torque for the slip angle departs significantly from that of approximate straight line slope.

Abstract: The adaptive brake application and initial skid detection system allows rapid brake application and prevents deep initial skids. Brake pressure is compared with a predetermined threshold brake pressure. Wheel velocity error signals are also generated to indicated the difference between the wheel velocity and a reference velocity signal. A pressure bias modulator integrator responsive to brake pressure signals adjusts the wheel velocity error signals to provide an anti-skid control signal. The pressure bias modulator integrator can also be initialized to the value of the measured brake pressure when the wheel velocity error signals indicate the beginning of a skid. Brake pressure difference signals are generated to indicate the difference between brake pressure and a commanded brake pressure, and an adjusted brake pressure error signal is generated in response to the brake pressure difference signals.

Abstract: A vehicle braking system has two driver-operable input devices. The vehicle braking system is sufficiently configured such that one of the driver-operable input devices is effective in causing resistance to the rotation of at least one wheel only when a predetermined condition exists, and the other driver-operable input device is effective independent of the predetermined condition.

Abstract: A method for electronically regulating brake force distribution to the front axle and the rear axle of a motor vehicle (EBV control), wherein the rotational behavior of the vehicle wheels is determined, compared with the vehicle speed or vehicle reference speed and/or with the changes of these variables, and evaluated to limit the slip on the rear-wheel brakes by modulating the braking pressure. The brake force distribution is controlled in dependence on the sum signals obtained by addition of acceleration values determined on each individual rear wheel and/or by addition of slip values determined on each individual rear wheel. It is particularly arranged for to weight the sum signals with variable sum factors and evaluate them as a criterion for triggering the EBV control (so-called EBV plus control).

Abstract: In a brake control system for a vehicle, a target wheel cylinder pressure of each wheel is calculated in accordance with a braking force applied by the driver, a brake control mode is determined to be one of an increase pressure mode, a decrease pressure mode, or a maintain pressure mode, and a target increase/decrease force slope is calculated in accordance with a slip amount of the wheel. In particular, the target wheel cylinder pressure is calculated based on actual wheel cylinder pressure and the target increase/decrease pressure slope, set on the target increase/decrease force slope when starting anti-skid control, the target wheel cylinder pressure is calculated after starting the anti-skid control based on the most recent target wheel cylinder pressure and the target increase/decrease pressure slope, and the wheel cylinder pressure Pi is controlled so as to become equal to the target wheel cylinder pressure.

Abstract: In a vehicle brake control device, it is determined whether a first starting condition, that a master cylinder pressure and a rate of change of the master cylinder pressure are equal to or more than respective first reference values, is satisfied. Furthermore, it is determined whether a second starting condition is satisfied based on a determination as to whether the master cylinder pressure is equal to or more than a second reference value at a time when a predetermined time has elapsed since a time when the first starting condition was satisfied. In a case where the second starting condition is determined as being satisfied, a brake assist control is executed until a termination condition of the brake assist control is satisfied.

Abstract: For determining a reference speed which is approximated to the actual vehicle speed, at least two wheel sensors are provided for each wheel speed to be measured. All existing wheel sensors are analyzed, and only one is selected and used for determining the reference speed as a function of the actual driving condition and of at least one defined speed criterion. At least one sensor is always available for controlling each wheel, even if one sensor is faulty.

Abstract: The present invention relates to a brake pressure control device, more particularly, for anti-lock pressure control and for automatic brake intervention for the purpose of traction slip control and/or driving dynamics control in automotive vehicle brake systems, including accommodating bores for pressure modulation valves arranged in a housing, pressure sensor connecting ports which lead into the housing and into which there are inserted pressure sensors that sense the pressure in a housing-side pressure fluid conduit respectively connected to a brake pressure generator. The pressure sensor connecting port either opens into the pressure fluid conduit between two accommodating bores that are directed into the housing, or is part of the pressure modulation valve.

Abstract: A control system (12) for an automotive vehicle includes a wheel speed sensor (18) generating a rotational speed signal and a controller (14) coupled to the wheel speed sensor. The controller determines a vehicle speed, calculates wheel slip based upon the vehicle speed and the rotational speed, calculates a predicted future wheel slip based upon the vehicle speed and the rotational speed, estimates a normal force on the wheel, calculates a modified brake torque signal in response to the wheel slip, the predicted future wheel slip and the normal force, and actuates the wheel brake in response to the modified brake torque signal.

Abstract: In a vehicle hydraulic brake system of a type adapted to release brake fluid discharged from the wheel cylinders into a reservoir for a master cylinder during pressure reduction phase of antilock brake control or vehicle stability control, the volume of the pressure chamber of the master cylinder can decrease until it becomes impossible to further increase pressure as a result of repeated pressure increase and reduction. An inexpensive solution to this problem is provided. The solution includes means for estimating the amount of pressure increase and/or pressure reduction of the wheel cylinders, and solenoid valves provided in a line connecting a pressure source with the master cylinder pressure chamber and adapted to be opened for a calculated time period.

Abstract: A method and/or a device for estimating pressure and/or volume changes in a hydraulic system having two peripheral volume storage vessels connected to a central volume storage vessel, in which, to increase the response rate, the estimate is based at least at times on a model in which a direct connection to the peripheral volume storage vessels is assumed, regardless of whether or not the peripheral volume storage vessels are simultaneously connected directly to each other.

Abstract: A combination brake and anti-lock system for a wheeled vehicle such as an aircraft includes an operator controlled source of pressurized hydraulic fluid for selectively applying hydraulic pressure to a hydraulically actuated wheel rotation braking device which responds to the applied hydraulic pressure to apply a braking force to a wheel of the vehicle to thereby arresting wheel motion. There is a low pressure hydraulic fluid return with a normally open hold valve in circuit between the source and the braking device for selectively opening and closing a fluid flow path from the source to the braking device and a normally closed decay valve in circuit between the braking device and the return for selectively opening and closing a fluid flow path from the braking device to the return.

Abstract: In an antiskid brake control system, an ECU estimates a wheel slip in accordance with a sensed wheel speed and controls a fluid pressure control valve for braking operation in accordance with the estimated wheel slip for an antiskid brake control, the fluid pressure being reduced when the wheel slip is enlarged and being increased when the wheel slip is lowered. When a vehicle-body speed is smaller than a predetermined quick pressure reduction prohibiting speed, the ECU performs a quick pressure reduction prohibiting control to restrain a quick pressure reduction having a greater reduction amount than a predetermined reduction amount.

Abstract: A device for controlling the wheel slip, particularly for controlling the brake slip and/or the drive slip of individual wheels for a motor vehicle, by which a braking pressure applied to the vehicle wheels can be varied and/or set as a function of the movement behavior of the vehicle wheels, having means for braking, particularly for locking, at least the front wheels and/or the rear wheels of the motor vehicle in the event a skidding condition is detected, the vehicle having wheel-speed sensors (5) whose signals contain information about the direction of rotation of the respective wheel, these signals being processed within the framework of a skid detection.

Abstract: In a vehicle hydraulic brake system of a type adapted to release brake fluid discharged from the wheel cylinders into a reservoir for a master cylinder during pressure reduction phase of antilock brake control or vehicle stability control, the volume of the pressure chamber of the master cylinder can decrease until it becomes impossible to further increase pressure as a result of repeated pressure increase and reduction. An inexpensive solution to this problem is provided. The solution includes means for estimating the amount of pressure increase and/or pressure reduction of the wheel cylinders, and solenoid valves provided in a line connecting a pressure source with the master cylinder pressure chamber and adapted to be opened for a calculated time period.

Abstract: A hydraulic brake apparatus for a vehicle includes a brake operating member, a hydraulic pressure generating source, a regulating valve, a master cylinder having first and second pistons, a pressure detecting means connected to a second pressure chamber for detecting a brake hydraulic pressure outputted from the second pressure chamber, a brake operating amount detecting means for detecting an operating amount of the brake operating member, and a judging means for judging a hydraulic pressure condition of first and second hydraulic systems respectively connected to first and second chambers based upon the brake hydraulic pressure detected by the pressure detecting means relative to the operating amount of the brake operating member detected by the brake operating amount detecting means.

Abstract: The solenoid current increases at low temperatures and decreases at high temperatures because the modulus of elasticity of an elastically deformable valve body and the slide resistance of an elastically deformable seal member vary with temperatures. Therefore the solenoid current for opening the valve mechanism from a closed position is required to be changed with low and high temperatures. To supply the solenoid current necessary for opening the valve mechanism without directly measuring the temperature, the solenoid current (the boost starting current leaning value) indicated when the pressure varies with the opening of the valve mechanism is recorded at the time of pressure-increasing, and thereafter when the valve mechanism is opened again after the closing of the valve mechanism, the solenoid current computed on the basis of the pressure-increase starting current learning value thus recorded is supplied.

Abstract: An actuating unit (1) for a wheel brake (2) of a motor vehicle has a hydraulic pump (12), which can be driven at variable speeds by an electric motor (11) and supplies pressure fluid from a storage tank (22), and has an element (24), which adjusts a return flow of pressure fluid to the pump (12) and is disposed between the pressure side (13) and the suction side (16) of the pump (12). In addition, a cylinder-piston unit (3) is provided, which is for pressing a brake lining (7) against a friction element (8) connected to a vehicle wheel. For purposes of controlling the brake pressure as a function of wheel slip, a pressure increase valve (18) and a pressure decrease valve (21) are disposed between the pump (12) and the cylinder-piston unit (3). In addition, a control unit (29) is provided, which can process electrical brake request signals and slip signals and can control the electric motor (11), the element (24), and the valves (18, 21).