Abstract: An anti-lock control member controls so as to realize any of a pressure decreasing mode where a normally-opened electromagnetic valve is closed, while a normally-closed electromagnetic valve is opened, a holding mode where the normally-opened electromagnetic valve is closed and the normally-closed electromagnetic valve is closed, and a pressure increasing mode where the normally-opened electromagnetic valve is opened, while the normally-closed electromagnetic valve is closed. Then, in the holding mode, for example, in the event that a predetermined condition is established where the voltage of a power supply for a vehicle or the terminal voltage of the normally-opened electromagnetic valve is equal to or smaller than a set value which is determined in advance, a current value that is applied to the normally-opened electromagnetic valve is controlled so as to become smaller than a current value that is applied to the normally-opened electromagnetic valve in the pressure decreasing mode.

Abstract: Noise produced during a supplemental brake apply is reduced eliminated by reducing the quantity of additional brake fluid supplied to the pump during the apply. The prime valve is opened only at the initiation of the supplemental apply to supply a predetermined small quantity of brake fluid to the accumulator and pump inlet and is then closed for the remainder of the apply. The quantity of extra fluid supplied can be retained by the accumulator and does not need to by blown off back to the master cylinder. The apply valve of the non-regulated wheel brake is controlled to regulate pressure to the regulated wheel brake through the apply valve thereof, which is left open while the release valve of the regulated wheel brake is left closed. The release valve of the non-regulated wheel is controlled to maintain a lower pressure at the non-regulated wheel, preferably equal to the master cylinder pressure whenever possible, while permitting fluid flow back to the accumulator.

Abstract: A hydraulic brake device is provided with a master cylinder for supplying pressurized fluid to plural brakes which respectively restrict the rotations of road wheels, a solenoid block mounted on the master cylinder and containing plural solenoid valves, and an ECU provided with a control board for controlling the solenoid valves to distribute pressurized fluid to the plural brakes and also provided with a case for containing the control board therein. The solenoid block and the ECU are constructed to be an integrated structure, and the integrated structure composed of the solenoid block and the ECU is removably mounted on the master cylinder. Further, the ECU is secured to the solenoid block by means of screw bolts which are arranged within an area insider the external form of the control board. Thus, it becomes unnecessary to provide bolt seats for the screw bolt outside the case, so that the case and hence, the ECU can be miniaturized.

Abstract: A brake control system includes an ECU having an estimate part which is so constructed as to: totalize an influent amount of fluid in a brake actuator in accordance with an output time of a valve opening drive signal of a control signal and a supply amount per unit time of fluid in a pressure control valve; estimate an amount of fluid in the brake actuator in accordance with the influent amount as totalized; estimate a value of the fluid pressure within the brake actuator in accordance with the amount of fluid as estimated; and carry out correction for obtaining a supply amount of fluid in the brake actuator when a time of retaining operation performed by the control signal is smaller than a predetermined value, correction being performed by adding a correction value corresponding to the time to the output time of the valve opening drive signal of the control signal.

Abstract: A damping force control type hydraulic shock absorber includes a plunger having a small-diameter main body portion slidably guided by a first fixed core made of a magnetic material. The plunger has a large-diameter attracted portion at an end thereof closer to a second fixed core. The diameter (D2) of the attracted portion is set larger than the diameter (D1) of the main body portion (D2>D1), thereby increasing the area of the mutually opposing surfaces of the attracted portion and the second fixed core. Accordingly, attraction force acting on the attracted portion can be increased without reducing the magnetic flux density at the main body portion.

Abstract: The present invention relates to a device for controlling electromagnetically operable valves of an electrohydraulic brake system for motor vehicles of the ‘brake-by-wire’ type having an electronic control or regulation unit that comprises at least one valve driver stage.

Abstract: A brake control device for a vehicle includes a master cylinder, a wheel cylinder, a brake pedal behavior simulator, a normally-open type electromagnetic valve, a normally-closed type electromagnetic valve, and a brake pressure control device. The brake pressure control device includes a pump, a reservoir, and two electromagnetic valves to increase and decrease wheel cylinder hydraulic pressure. When the brake pressure control device is normally operated, a hydraulic pressure in the wheel cylinder is controlled by the brake pressure control device. On the other hand, when the brake pressure control device malfunctions or is abnormally operating, the wheel cylinder hydraulic pressure is controlled by hydraulic pressure generated from the master cylinder. At least the normally-closed type electromagnetic valve is opened when the brake pedal is in the non-operational state.

Abstract: A hydraulic brake apparatus for a vehicle includes a hydraulic pressure generator which generates and outputs a power pressure irrespective of brake pedal operation, a regulation valve which regulates the power pressure to a predetermined pressure corresponding to the brake pedal operation force and outputs the predetermined pressure, and a master cylinder having a master cylinder pressure chamber and an auxiliary pressure chamber connectable to an output side of the regulation valve. The master cylinder is operated by auxiliary pressure in the auxiliary pressure chamber to generate a master cylinder pressure corresponding to the auxiliary pressure. A wheel brake cylinder is operated by the master cylinder pressure to apply braking force to a wheel. A pressure modulation device is disposed in a pressure passage connecting the output side of the regulation valve to the auxiliary pressure chamber to modulate the auxiliary pressure to a pressure less than the predetermined.

Abstract: A brake control apparatus for a motor vehicle includes first and second pressure regulators that regulate a pressure of a hydraulic fluid supplied from a high-pressure fluid supply source to first and second wheel cylinders, and a communication control device that controls fluid communication between the first and second wheel cylinders. A controller of the apparatus includes first and second control units that control the first and second pressure regulators, respectively. The controller determines whether one of the first and second control units may be failing to operate normally, and places the communication control device in an operating position for communicating the first and second wheel cylinders with each other when it is determined that the first or second control unit may be failing to operate normally.

Abstract: An actuator assembly for a vehicle brake system comprises a piston disposed in a bore, a reservoir, and a solenoid. A channel is in fluid communication between the bore and the reservoir, and the solenoid is disposed in the channel. The solenoid is movable between an open position and a closed position. In the closed position, the solenoid blocks fluid communication between the bore and the reservoir.

Abstract: A brake control system and method that includes high-pressure fluid supply sources and cutoff devices for cutting off communication between a master cylinder and wheel cylinders during a control process. A determination is made whether there is inconsistency between detection values of two pressure detectors for detecting a pressure in the master cylinder and a detection value of a stroke detector for detecting a stepping-on stroke of a brake pedal. A final target deceleration of the vehicle is calculated based on the detection values that are consistent with each other and braking force of each wheel is controlled based on the final target deceleration.

Abstract: The present invention provides a proportional microvalve having a first, second and third layer, and having high aspect ratio geometries. The first layer defines a cavity with inlet and outlet ports. The second layer, doped to have a low resistively and bonded between the first and third layers, defines a cavity having a flow area to permit fluid flow between the inlet and outlet ports. The second layer further defines an actuatable displaceable member, and one or more thermal actuators for actuating the displaceable member to a position between and including an open and a closed position to permit or occlude fluid flow. The third layer provides one wall of the cavity and provides electrical contacts for electrically heating the thermally expandable actuators. The thermal actuators and the displaceable member have high aspect ratios and are formed by deep reactive ion etching such that they are displaceable in the plane of the second layer while being very stiff out of the plane.

Abstract: A hydraulic brake apparatus for a vehicle comprises a master cylinder and an auxiliary hydraulic pressure source. A master cylinder hydraulic pressure outputted from the master cylinder is adjusted by adding a master cylinder hydraulic pressure in response to an operation of a brake operating member to a master cylinder hydraulic pressure at an auto-braking control when the brake operating member is operated during the auto-braking control. The master cylinder hydraulic pressure is adjusted by controlling an operation of a valve means so as to increase a power hydraulic-pressure supplied from the auxiliary hydraulic pressure source to a regulating means corresponding to the amount of the operation of the brake operating member.

Abstract: A method of employing a hydraulic unit of a brake system containing brake lines extending between a master cylinder and wheel brakes and valves which are actuatable by exertion of magnetic force and which have removable electrical coils and when unactuated assume their blocking position, including the steps of removing coils from the valves; connecting the hydraulic unit, toward the master cylinder or the wheel brakes, to an air source of adequately high pressure; switching the valves to their open position by the exertion of magnetic force of a permanent magnet; positively displacing the pressure medium contained in the hydraulic unit from the air source by air and caught.

Abstract: A brake by wire system is integrated with a brake transmission solenoid interlock (BTSI) unit to prevent a vehicle transmission from being shifted out of a park mode into a drive mode until a brake system operational state is determined. The BTSI is activated by a supplemental brake control unit, which receives a transmission release signal from a brake system controller upon receipt of a brake intent signal from one or more brake pedal sensors after a diagnostic program has determined the brake system operational state. The supplemental brake control unit includes a switch responsive to the transmission release signal to close the BTSI activating circuit and permit release of the transmission. In a split brake system with two brake controllers, the supplemental brake control unit may include a switch controlled by a logic (OR, AND) circuit or a pair of switches in an equivalent logical circuit configuration.

Abstract: Actuator unit for a hydraulic vehicle brake system, with a master brake cylinder in which a first piston, which can be displaced by an actuator, is disposed, a first brake circuit which can be connected by a valve arrangement in a basic position to the master brake cylinder or separated from the latter thereby in an actuating position, and a device which can be connected to a hydraulic chamber of the master brake cylinder to simulate the brake pedal behaviour, wherein a second piston is disposed in a displaceable manner in the master brake cylinder, wherein the displacement of one piston causes the displacement of the other piston, wherein the device for simulating the brake pedal behaviour is switched to an active or inactive mode through the displacement.

Abstract: A compressed-air processing system, notably for motor vehicles, includes, in a housing, an electromagnetic pressure regulator and a multicircuit safety valve having at least one load circuit connected to it. Each load circuit can be locked separately by an assigned pressure control unit. Reliable and economical operation of the system is achieved by positioning a pressure limiter between at least one of the pressure control units and the pressure regulator output and by the fact that in the zero-current state, the pressure limiter acts on a supply hole for the control unit so as to limit the output pressure to a defined value.

Abstract: A method and apparatus for calculating the actuation control of a hydraulic sub-system of a braking system in order to reduce noises associated with the hydraulics is presented. Input signals and measured/determined characteristics are utilized to calculate a value of a drive time for an inlet valve, a value of a pulse width modulator output, a duration of a current signal reduction time and a pulse width modulator value associated with the current signal reduction time, all of which determine actuation control of the hydraulic sub-system.

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 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: An actuator assembly for a vehicle brake system comprises a piston disposed in a bore, a reservoir, and a solenoid. A channel is in fluid communication between the bore and the reservoir, and the solenoid is disposed in the channel. The solenoid is movable between an open position and a closed position. In the closed position, the solenoid blocks fluid communication between the bore and the reservoir.

Abstract: A brake system and method of controlling the system are disclosed. The system provides secondary hydraulic braking in a de-energized mode. The system includes a wheel brake associated with wheels of a vehicle typically at each corner of the vehicle. The wheel brake typically includes a caliper or drum for deceleration of the vehicle. The system includes a master cylinder in fluid communication with the wheel brake. In the de-energized mode, the master cylinder operates the wheel brake. A solenoid isolation valve decouples the master cylinder from the wheel brake when the system is in a normal, i.e., an energized, mode. As such, the master cylinder is isolated from the wheel brake and is prevented from operating the wheel brake. Alternatively, in the de-energized mode, the isolation valve couples the master cylinder with the wheel brake to provide the secondary hydraulic braking.

Abstract: The invention relates to a device for making contact between a solenoid and an electronic control unit arranged neighboring a valve block, wherein the solenoid projects away from a side wall of the valve block by a magnetic coil and a magnetic core, contact elements being arranged in an end face region of the solenoid facing towards the valve block in such a way that the contact elements can be directly electrically connected to corresponding contact elements arranged on a wall of the electronic control unit or of the valve block.

Abstract: A vehicle hydraulic brake apparatus includes a linear solenoid valve unit for controlling a power hydraulic pressure supplied to a master cylinder from an auxiliary hydraulic pressure source. Master cylinder hydraulic pressure from the master cylinder detected by a pressure sensor is compared with a predetermined reference hydraulic pressure when the linear solenoid valve unit is electrically excited under a condition that the communication between the master cylinder and the wheel cylinders is interrupted by a hydraulic pressure control valve device disposed between the master cylinder and the wheel brake cylinders while the vehicle engine is activated and a brake operating member is not operated. The electric current supplied to the linear solenoid valve unit is corrected in response to a result of this comparison.

Abstract: A brake fluid pressure retaining unit for retaining brake fluid pressure within a wheel cylinder after releasing a brake pedal is disclosed. The brake fluid pressure retaining unit includes a brake fluid pressure reduction speed control device for retaining reduction speed of the brake fluid pressure within the wheel cylinder less than that of brake pedal load applied by a driver. The brake fluid pressure reduction speed control device may be formed by a restriction in a brake fluid pressure circuit arranged between a master cylinder at which the brake fluid pressure is generated in accordance with a brake pedal load applied by the driver and the wheel.

Abstract: An anti-locking brake system for a land vehicle, which is set up in particular for traction control and vehicle dynamics control, comprises a pump (42) for actuating a wheel brake (37) which removes brake fluid from a brake pressure generating unit (31) and supplies it to the wheel brake (37), wherein a first valve arrangement (1) blocks in a non-actuated (normal) position (1.1) the connection between the brake pressure generating unit (31) and an input connection (42e) of the pump (42) and in at least one actuated position (1.3) establishes a primary flow connection (A), a first electromagnetic valve (50) establishes in a non-actuated position (50.1) the connection between an output connection (42a) of the pump (42) and the brake pressure generating unit (31), and blocks it in an actuated position (50.

Abstract: In a brake system of a vehicle in which a pair of wheel cylinders are supplied with a fluid pressure by a fluid circuit having a pair of inlet control valves for selectively connecting the pair of wheel cylinders respectively to an outlet port of a motor-driven pump and a pair of outlet control valves for selectively connecting the pair of wheel cylinders respectively to a fluid reservoir, a brake control device controls the motor driving of the pump and opening/closing of the inlet and outlet control valves, such that a controlled fluid pressure is supplied to the pair of wheel cylinders at least temporarily with the pair of inlet control valves substantially fully opened, while the pair of outlet control valves substantially closed, wherein it is judged if there is a difference between output signals of a pair of wheel cylinder pressure sensors beyond a predetermined threshold value, thereby judging the pair of wheel cylinder pressure sensors to be both operating normally when the difference is not larger t

Abstract: A pressure sensor is integrated upon a solenoid valve by attaching at least one micro-machined strain gauge to an end of the solenoid valve sleeve. The solenoid valve is included in a vehicle brake control system. As the hydraulic fluid pressure in the brake system changes, the end of the solenoid valve sleeve is deflected, causing a change in an electrical property of the strain gauge. The stain gauge is included in a bridge circuit that is electrically connected to a signal conditioning circuit. The signal conditioning circuit generates a pressure signal that is a function of the change in the electrical property of the strain gauge.

Abstract: A method and apparatus for calculating the actuation control of a hydraulic sub-system of a braking system in order to reduce noises associated with the hydraulics is presented. Input signals and measured/determined characteristics are utilized to calculate a value of a drive time for an inlet valve, a value of a pulse width modulator output, a duration of a current signal reduction time and a pulse width modulator value associated with the current signal reduction time, all of which determine actuation control of the hydraulic sub-system.

Abstract: The present invention is directed to a brake control system for a vehicle, wherein a first valve device for opening or closing a main passage, a hydraulic pressure pump, and a second valve device for opening or closing an auxiliary passage are disposed in each hydraulic pressure circuit of a dual hydraulic pressure circuit system. At least one of the first and second valve devices is controlled to equalize the slip rates of a pair of wheels, with the wheel brake cylinders operatively mounted thereon and disposed in different hydraulic circuits, and placed at the left side and right side of the vehicle, respectively, when a difference between the slip rates of the wheels placed at the left side and right side exceeds a predetermined value.

Abstract: A hydraulic system for actuating at least two operating systems of a motor vehicle has a first hydraulic medium reservoir for storing a hydraulic medium. A distribution valve is connected to the first hydraulic medium reservoir and to the operating systems of the motor vehicle. A control unit is connected to the distribution valve which is configured to distribute the hydraulic medium from the first hydraulic medium reservoir to the operating systems of the motor vehicle and to control flow of the hydraulic medium to the operating systems of the motor vehicle such that one of the operating systems has priority with regard to supply of the hydraulic medium. A first one of the operating systems is a brake device having a brake power assist unit, a brake valve, and a master brake cylinder. The brake power assist unit is connected via the brake valve to the control unit.

Abstract: Existing valve control devices are set up in housings that feature also the complete yoke in addition to the valve spools.

Abstract: In a method and a device for controlling a brake system, the wheel brake pressure is set at the wheel brakes electrically as a function of the driver's braking input. The high-pressure supply arrangement for pressure buildup, for which at least one pump and one accumulator are provided, is monitored by comparing the change in accumulator pressure to a least one permissible limiting value. In the case of a fault in the pressure supply, it is made possible for the driver to grip through hydraulically to the wheel brakes.

Abstract: The present invention is a safety-enhancing automatic air parking brake actuator system that automatically actuators the air brakes in an engaged condition when one or more dangerous conditions exist at various stations around/in the vehicle or equipment. The preferred actuator system operates on the principle that the brake actuator system is electrically connected to the various stations, and, when a circuit including the actuator unit is interrupted, a solenoid valve of the actuator system closes and vents, to cut off the air supply to the air brakes to engage the brakes. The stations may include the vehicle ignition, one or more doors, a wheelchair lift, a dump truck bed, a backhoe arm, or other equipment.

Abstract: The pump is connected on its delivery side through an auxiliary passage to a primary passage connecting the master cylinder and brake cylinder to each other, and a pressure control valve is provided in a portion of the primary passage between the master cylinder and a point of connection thereof to the auxiliary passage. The pressure control valve releases working fluid from the pump to the master cylinder when delivery pressure of the pump is higher than the master cylinder pressure by more than a predetermined amount, and the pump is activated when the fluid pressure generated in the brake cylinder is required to be higher than the master cylinder pressure, during brake operation.

Abstract: An inexpensive hydraulic brake system for a vehicle including an antilock device, by means of which brake pressures in front wheel brakes and rear wheel brakes of a four-wheeled vehicle that are connected to diagonal brake circuits can be changed to a large extent independently of one another in order to reduce or eliminate the danger of wheel locking. The antilock device should have one return feed pump per brake circuit. The brake system is equipped with the antilock device with a total of six electrically controllable valves. In each of the brake circuits a first valve is disposed between the master cylinder and a front wheel brake and a second valve is disposed between the master cylinder and the rear wheel brake and a third valve is disposed between the front wheel brake and an inlet of each of the return feed pumps.

Abstract: An electro-hydraulic braking system for motor vehicles. The system includes a brake pedal and a braking device associated with at least one vehicle wheel which is brought into communication with an electronically controlled valve arrangement in order to apply hydraulic fluid under pressure to the braking device. A fluid pressure accumulator fed by the pump provides a pressurized hydraulic fluid which can be passed to the braking device by way of an electronically controlled valve arrangement in order to apply hydraulic fluid in proportion to the driver braking demand as sensed at the brake pedal in the “brake by wire” mode. A first device within the system provides a level of fluid pressure supply within the electro-hydraulic system whose highest value is less than that sufficient for the maximum possible braking demand level which may be required.

Abstract: A multi-way pressure control valve for an electromagnetically actuatable multi-way control valve for slip-controlled hydraulic automotive vehicle brake systems, for providing a flow connection between at least one wheel brake and a high-pressure source or a low-pressure accumulator.

Abstract: A switchable solenoid valve is disposed between the master cylinder port and the wheel caliper port for an anti-lock brake system. The switchable solenoid valve includes a valve housing, a valve seat that includes a center orifice and a plurality of perimeter bores, and an axially moveable valve plate and tappet for sealing against the valve seat. The switchable solenoid valve is movable between a normally open position, a closed position and an intermediate position that occurs when the brake system is in anti-lock mode. In the open position, both the valve plate and tappet are spaced away from the valve seat to allow unrestricted pressure fluid flow between the master cylinder and the wheel caliper. When the solenoid valve is moved in to the closed position, the valve plate is in face-to-face engagement with the valve seat to seal the perimeter bores while the tappet is simultaneously sealingly engaged with the center orifice.

Abstract: A pre-engagement for a braking pressure modulator for a pressure regulating circuit of an electronic braking system of a vehicle includes a first pneumatic inlet through which a supply pressure is supplied to the pre-engagement unit, a second pneumatic inlet through which a redundancy pressure is supplied to the pre-engagement unit, a first pneumatic output terminal through which the pre-engagement unit is connected to an air quantity augmenting relay valve, and a second pneumatic output terminal through which the pre-engagement unit is connected to a pressure sink. The pre-engagement unit also includes an electrically actuated valve system having a plurality of solenoid valves, including a plurality of interconnected pneumatic terminals, and a plurality of electrical terminals which are connected to output terminals of an electronic control unit. An electric braking command signal transmitter delivers a driver initiated electric brake value setting to an input of the electronic control unit.

Abstract: A one-time bleed valve with reset capability for an anti-lock hydraulic control unit comprises a piston adapted to be sealingly installed in a bore made in a body of the hydraulic control unit in response to a brake pressure. The bore is located in a portion of the body that is immediately under a recessed part of the body that accommodates a normally open electromagnet valve. On its one end, the bore is in communication with a primary hydraulic pressure circuit, whereas on another its end it is connected with a low-pressure line. Owing to such a structure, when the piston sits loosely in the bore, an air communication is established between the primary hydraulic pressure circuit and the low-pressure line, and air can evacuate from the low-pressure brake circuit on exposure to a vacuum applied to the primary hydraulic pressure circuit. To provide the bleed valve with a reset capability, an access hole is made between outside of the body and the bore.

Abstract: A method and device for estimating pressure changes within a hydraulic system having a first reservoir and at least one second reservoir connected to the first reservoir via valves, including the following steps: (a) specifying a pressure differential between the first and second reservoirs; (b) calculating a volume exchanged within a specified time interval between the first and second reservoirs via the valve, on the basis of a value for the pressure differential that is valid at the start of the time interval; (c) calculating a volume to be exchanged between the two reservoirs to achieve equal pressures in them; (d) if the amount of the exchanged volume calculated in step (b) is greater than the volume to be exchanged as calculated in step (c), replacing the value of the exchanged volume with that of the volume to be exchanged; and (e) adopting the volume value obtained in step (d) as the change in the volume in the second reservoir and determining the pressure change in the reservoirs on the basis of

Abstract: In a brake by wire system, a linear differential pressure control valve is provided to control accurately wheel cylinder pressure. A brake fluid conduit extending from a reservoir is branched out into two conduits, each of which is transmitted to each of right and left wheel cylinders. A linear differential pressure control valve is disposed in the conduit and an another linear differential pressure control valve in each of the branched out conduits. Brake fluid sucked from the reservoir by a motor pump is discharged to each of the branched out conduits between the valve and the wheel cylinder. The two valves thus connected in series are operative step by step to control the wheel cylinder pressure in accordance with the current commanded in response to brake pedal depression.

Abstract: A vehicle brake system including a wheel brake and a master cylinder operable to provide pressurized fluid to the wheel brake. The master cylinder includes a housing having a bore formed therein, and further including a piston slidably disposed in the bore. The brake system further includes a fluid reservoir in selective fluid communication with the bore of the master cylinder. The brake system also includes an isolation valve movable between an open position, wherein fluid is permitted to flow between the master cylinder and the wheel brake, and a closed position, wherein fluid is restricted from flowing between the master cylinder and the wheel brake. The brake system further includes a dump valve movable between a closed position, wherein fluid is prevented from flowing between the wheel brake and the reservoir, and an open position, wherein fluid is permitted to flow between the wheel brake and the reservoir.

Abstract: A braking hydraulic pressure control apparatus for a vehicle comprising switching valve capable of switching between communicating and shut-off states between a master cylinder and hydraulic passages, and between communicating and shut-off states between the master cylinder and open passages. A driving-wheel control valve is also provided for controlling hydraulic pressure in driving-wheel brakes, and pumps whose inlet ports are connected to respective reservoirs and whose discharge ports are connected to respective hydraulic passages. The open passages are connected to the inlet ports of the respective pumps to improve the ability to remove air from the hydraulic pressure system, and allow simpler air-removing equipment to be utilized. The switching valve comprise opened-type and closed-type electromagnetic valves. Opened-type electromagnetic valves are positioned between the master cylinder and the hydraulic passages.

Abstract: An hydraulic braking system of the brake-by-wire type has an hydraulic pressure source comprising an hydraulic accumulator adapted to be charged by a pump. An accumulator isolating valve is so positioned and biased to correspond to the direction of flow from the accumulator to a solenoid-operated proportional valve. The valve is biased into a closed position in opposition to the flow from the pump to the accumulator.

Abstract: A brake system including a master cylinder for generating pressurized fluid, a wheel brake in fluid communication with the master cylinder, and a first valve for regulating the flow of fluid between the master cylinder and the wheel brake. The brake system further includes a pedal travel simulator including a housing having a bore formed therein. A piston is slidably disposed in the bore. The piston and the housing generally defining a fluid chamber which is in fluid communication with the master cylinder. The pedal travel simulator further includes a spring which biases the piston in a direction so as to contract the fluid chamber. The brake system further includes a source of pressurized fluid and a boost valve which is in fluid communication with the source of pressurized fluid and the wheel brake.

Abstract: The present invention relates to a method of bubble-free filling of brake fluid into a hydraulic automotive vehicle brake system, which is equipped with slip control and/or automatic braking intervention, the pump of which, under operating conditions, delivers brake fluid from the secondary circuit into the primary circuit according to the return delivery principle. In this arrangement, exclusively the primary circuit is bled and filled with undersaturated brake fluid.