Abstract: An automotive braking system controls the flow of pressurized brake fluid from a tandem master cylinder to several wheel brakes via a pair of braking circuits. Each circuit features a pressure relief line having, in series, a normally-closed valve, low-pressure accumulator, check valve, pump, damping chamber, and throttling orifice. A bypass line including a normally-closed bypass valve that is operated to interconnect the pressure relief lines of the first and second braking circuits proximate to the suction side of the pump, preferably downstream of the wheel brake outlet valves between the low-pressure accumulator and the check valve, selectively feeds fluid from one braking circuit to the other braking circuit to thereby reduce system response time when, for example, one or more wheel brakes driven by the other braking circuit is actuated to enhance vehicle traction or stability.

Abstract: An apparatus for controlling a pump driving motor includes estimated fluid volume obtaining means for obtaining an estimated volume of a brake fluid discharged to a reservoir, hydraulic pump controlling means for specifying the number of rotations of the motor for driving a hydraulic pump based on the estimated volume and for driving the hydraulic pump with the specified number of rotations, and changing means for changing the number of rotations of the motor to be smaller than the number of rotations specified on the basis of the estimated volume in a case where an actual time defined from a driving start of the hydraulic pump to a point where the brake fluid in the reservoir actually turns to zero is shorter than an estimated time over which the estimated volume turns to zero by a driving of the hydraulic pump with the specified number of rotations of the motor.

Abstract: Braking system including a master cylinder having at least two pressurizing pistons partially defining at least two mutually isolated pressurizing chambers, and wherein a working fluid in each pressurizing chamber is pressurized by an advancing movement of the corresponding pressurizing piston, a hydraulically operable brake cylinder for activating a brake, and a valve device having a first state in which the pressurized fluid is delivered from two pressurizing chambers of the at least two pressurizing chambers to the brake cylinder, and a second state in which the pressurized fluid is delivered from only one of the two pressurizing chambers.

Abstract: A vehicle brake system is provided with a brake ECU serving as controlled hydraulic brake force control means for executing a controlled hydraulic brake force control to decrease the rotational speed of an electric motor when at least both of a regenerative brake force and a controlled hydraulic brake force are being applied. The brake ECU decreases the rotational speed of the electric motor when the gradient of a target controlled hydraulic brake force being a controlled hydraulic pressure command value given to a hydraulic brake device is downhill or is not present. Thus, the pressured fluid supplied from a pump driven by the electric motor to be supplied to wheel cylinders of a vehicle is decreased to enhance the efficiency in utilizing the regenerative energy which an electric motor for driving the vehicle has in dependence on the stepping state of a brake pedal.

Abstract: The present disclosure relates to a pump system for parking brakes for a rail vehicle. The pump system includes at least one actuator, at least one pump and a reservoir as a fluid source. Also included is a manifold in fluid communication with the reservoir and the actuator. Further included are a plurality of valves and fluid paths internal to the manifold to allow fluid flow among the at least one pump and the reservoir.

Abstract: A hydraulic control system for operating at least one hydraulic motor and at least one hydraulic brake. In one specific embodiment of the invention, the hydraulic motor and brake are part of an industrial vehicle.

Abstract: Braking system including a power-operated hydraulic pressure source operable to deliver a pressurized working fluid, a brake including a hydraulically operated brake cylinder, and a flow-rate changing device disposed between the power-operated hydraulic pressure source and the brake cylinder and operable to change a rate of flow of the pressurized working fluid into the brake cylinder, which rate corresponds to a given rate at which the pressurized working fluid is delivered from the power-operated hydraulic pressure source.

Abstract: A brake system for a vehicle is comprised of a first brake system that mechanically applies a braking force to wheels according to a master cylinder hydraulic pressure outputted from a master cylinder which receives a brake manipulation force of a driver, and a second brake system that apply a braking force to other wheels according to at least a braking state of the first brake system.

Abstract: In a vehicle brake control device, a target W/C pressure depending on an amount of operation performed to a brake operating member, exhibits hysteresis due to a forward mapping dataset and a backward mapping dataset. The vehicle brake control device selects the forward mapping dataset or the backward mapping dataset based on the amount of operation performed to the brake operating member, and determines a current value of a current to be supplied to one of first to fourth linear valves. Therefore, it is possible to prevent a wheel cylinder pressure from changing too sensitively to the operation to the brake operating member and from changing even when the driver is not intentionally operating the brake operating member. This makes the driver experience an improved brake feeling.

Abstract: In an ABS control, a vehicle brake control device detects a sudden change road in which a friction coefficient changes suddenly from a high value to a lower value and controls, based on the detection of the sudden change road, the currents to be supplied to a first and a second electrical motor in a first manner or a second manner, wherein in the first manner the currents are controlled so that the first and second electrical motors would eventually stop rotating if the motor control portion kept controlling the currents in the first manner for a sufficiently long time, and in the second manner the currents are controlled so that the first and second electrical motors would eventually start rotating in a reverse direction if the motor controlling portion kept controlling the currents in the second manner for a sufficiently long time.

Abstract: A vehicle braking apparatus is provided with a brake operating element that is operated by a driver, and an actuator that generates a braking force in accordance with a braking operation of the brake operating element. A controller is operatively arranged to control the actuator such that an increase in a rate of change of the braking force with respect to the braking operation by the driver is suppressed upon determining that vehicle cabin background noise is equal to or below a prescribed threshold value.

Abstract: In a method for joining at least two work pieces by friction stir welding wherein the work pieces are placed placed in overlapping relationship and are at least partially plasticized in the area where they are to be joined by a rotating friction tool provided with a pin-like projection which is moved axially into the area of the joint to be formed, the projection on the rotating tool has a length corresponding about to the thickness of the upper work piece and a shoulder around the pin-like projection so that, upon movement of the tool toward the work pieces, the work piece material is plasticized by the rotating pin-like projection which moves axially into the work piece material until it reaches the surfaces of the lowermost workpiece.

Abstract: A brake control apparatus for a vehicle includes controlling device having a target wheel cylinder pressure calculating portion, an accumulated motor rotation calculating device, and a motor actuation determining portion, wherein the brake fluid in the first and the second front and rear wheel cylinders are pressurized by driving the first, second, third and fourth linear valves and the first and the second motors when the necessary amount of brake fluid is judged to be larger than the current amount of brake fluid and the brake fluid in the first and the second front wheel cylinders, and the pressurizing of the first and the second rear wheel cylinders are stopped by reducing the number of rotations or stopping the rotation of the first and the second motors when the necessary amount of brake fluid is judged not to be larger than the current amount of brake fluid.

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 hydraulic control system for operating at least one hydraulic motor and at least one hydraulic brake. In one specific embodiment of the invention, the hydraulic motor and brake are part of an industrial vehicle.

Abstract: A vehicular brake control apparatus detects risky occasions and locations that may be risky by using, for example, an infrastructure information input device or a navigation device, and, for such locations and the like, performs the pre-charge so that braking force will be promptly generated. Therefore, the pre-charge can be precisely performed under necessary circumstances, irrespectively of the driver's accelerator operation. Hence, when the driver depresses the brake pedal at such a location or the like, braking force will be promptly generated. Thus, accidents and the like can be prevented.

Abstract: A tank according to the invention comprises a casing, a filling port (5) extending, on the outside of said tank, into a filling neck (7), which is provided with a screw thread having a pitch (p) and which cooperates with a cap (9). The inner surface of the cap cooperating with the screw thread, at least one outlet port for the hydraulic-fluid flow towards a hydraulic circuit. The inner space (3) of the tank is connected with ambient air through two channels (45), that extend from a first lengthwise end (47) of the filling neck (7) to a second lengthwise end (49) of the filling neck (7) and through a helical passage (41) between the filling neck (7) and the cap (9) to connect the inside of the tank with the ambient air to avoid the development of negative pressure in the tank.

Abstract: This brake hydraulic pressure control apparatus adopts, as the pressure-increasing valve, a normally-open linear solenoid valve that can linearly adjust the actual differential pressure. This apparatus repeatedly executes, in principle, a control cycle in which a pressure-reducing control, holding control and linear pressure-increasing control make one set, after ABS control start conditions are satisfied (after time t1). In this case, a pulse pressure-increasing control is executed instead of the linear pressure-increasing control only in the first-time control cycle (time t3 to t6).

Abstract: A brake device comprises a brake cylinder, a reservoir, a pump, a master cylinder, and a pulsation-reduction device. The reservoir serves to accumulate a working liquid discharged from the brake cylinder. The pump serves to pump the working liquid accumulated within the reservoir. The master cylinder serves to receive the working liquid discharged from the pump. The pulsation-reduction device comprises a valve device disposed in a communication channel connecting the downstream side of the pump and the master cylinder. The valve device comprises a spool disposed within the communication channel. The spool is movable along the communication channel in response to differences in pressure between the pump side of the communication channel and the master cylinder side of the communication channel. The movement of the spool operates to open and close at least a part of the communication channel.

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: An electronically controlled hydraulic brake system is configured to obtain an attainment brake hydraulic pressure which can be achieved when a motor drive current command value is applied to a pressure increasing pump motor, to set a virtual initial pressure of the brake hydraulic pressure, to obtain a linear compensation executed attainment brake hydraulic pressure by linearly compensating the attainment brake hydraulic pressure using the actual brake hydraulic pressure, to calculate an ideal flow rate of the pressure increasing pump from a hydrodynamic flow rate equation, to obtain the linear compensation executed attainment brake hydraulic pressure by executing an inverse calculation of the flow rate equation from the ideal flow rate and the actual brake hydraulic pressure, and to obtain a linear compensation executed motor drive current command value by executing an inverse calculation of the calculation for obtaining the linear compensation executed attainment brake hydraulic pressure.

Abstract: An actuating unit (1) for a wheel brake (2) of a motor vehicle has a hydraulic pump (14) that can be driven at variable speeds by an electric motor (13). In addition, a cylinder-piston unit (3) is provided, with a piston (6) and with cylinder chambers (7, 8) disposed on both sides of the piston. By means of the cylinder-piston unit (3), a brake lining (9) can be pressed against and lifted away from a friction element (10) connected to a vehicle wheel. A 4/3-port directional-control valve (15) is provided between the pump (14) and the cylinder-piston unit (3) and is used to modulate the pressure in the cylinder-piston unit. The actuating unit (1) is associated with a control unit (29), which can process an electric brake request signal and can control the electric motor (13) and the valve (15).

Abstract: A vehicle brake control system includes an electric fluid pump that, upon energization thereof, pumps brake fluid from a reservoir to a brake circuit at a position upstream of a pressure control valve, an inlet circuit connecting the inlet opening of the pump to a master cylinder, an inside gate valve installed in the inlet circuit, and a control unit that controls the pressure control valve, the inlet gate valve and the electric fluid pump and carries out a predetermined brake control to adjust the hydraulic pressure of the wheel cylinder by operating the pressure control valve. The control unit is configured to carry out a flow back control after completion of the predetermined brake control. The flow back control is a control wherein the inside gate valve is kept open having the electric fluid pump kept de-energized.

Abstract: A braking apparatus comprises a first contact unit arranged on the rotary shaft side of a wheel, at least a second contact unit for contacting the first contact unit for generating a friction force, an actuator for pressing the second contact unit against the first contact unit, and a control unit for controlling the operation of the actuator, wherein the control unit performs the position control operation for moving the second contact unit in such a manner that the interval between the first contact unit and the second contact unit is smaller than a preset distance, and the force control operation for pressing the second contact unit against the first contact unit in accordance with the required braking force.

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: A braking system comprised of a rotor, a plurality of actuators, a brake control unit and a by-pass valve. When in a brake-on mode of operation, the brake control unit effects braking by restricting the flow of a working fluid that is pumped in and out by each of the plurality of actuators as they engage the rotating rotor. The degree of restriction to the flow of the working fluid can be varied to adjust the amount of braking force applied. The brake system is self-energizing in that it is not reliant on a substantial external source to create the operating pressure necessary to effect braking. Operating the by-pass valve into a by-pass on position effectively negates the generation of braking forces normally resulting from operation into the brake-on mode of operation while still allowing the actuators to engage the rotor and working fluid to be circulated.

Abstract: Hydraulic pressure control apparatus for controlling a pressure of a brake cylinder pressure, including a pump device connected to the brake cylinder and including at least one set of a pump for delivering a pressurized fluid to the brake cylinder and a pump operating electric motor, a low-pressure source for storing the fluid discharged from the brake cylinder, a solenoid-operated pressure control valve disposed between the low-pressure source and the brake cylinder and operated with an electric energy applied thereto, for controlling the brake cylinder pressure depending upon the electric energy, and a controller including a pressure increase control device for increasing the brake cylinder pressure by controlling the electric motor, and a pressure reduction control device or reducing the brake cylinder pressure by controlling the electric energy applied to the control valve.

Abstract: A braking system including: a pressure control cylinder having a housing, a piston displaceable by activation of a drive source, and a pressure controlling chamber so that a working fluid can be supplied from the pressure controlling chamber to a brake cylinder, by displacement of the piston; and a braking pressure control device operable to control the activation of the drive source, for controlling a pressure of the working fluid in the pressure controlling chamber or in the brake cylinder. The braking-pressure control device includes: a piston-bottoming-state detecting portion operable to detect a piston-bottoming state of the pressure control cylinder and/or a possibility of occurrence of the piston-bottoming state; and a drive-source control portion operable to control the activation of the drive source on the basis of result of detection made by the piston-bottoming-state detecting portion.

Abstract: The present invention describes an electronic circuit arrangement with a motor vehicle control adapted to be activated by a current/voltage supply, wherein the motor vehicle control or the current/voltage supply for the motor vehicle control is connected to an activation unit for the independent activation of the motor vehicle control, and the motor vehicle control can be switched on or off by the activation unit, and it also describes the use thereof for the control and/or monitoring of electronic or electrohydraulic brake systems. Also described is a system wherein leakage of a pressure reservoir is monitored and the pressure reservoir is replenished by means of a filling device as soon as the pressure drops below a defined limit value during the temporally limited activation.

Abstract: If a hydraulic motor (23) (traveling wheel (27)) is rotated (or skidding) at high rate, and a hydraulic motor (24) is hardly rotated, a detection controller (68) compares the rotational speeds of both hydraulic motors (23, 24). Then the rotation detected by the rotation detectors (66, 67) to detect the traveling wheel (27) to be skidding, and moves a piston (71) to allow a negative brake (40) to give a braking force to the hydraulic motor (23), and rotate the hydraulic motor (24). In this way, this invention can release the traveling wheel from skidding without the use of a flow dividing valve.

Abstract: An improved electro-hydraulic brake system having an electrically powered normal source of pressurized hydraulic brake fluid, and a manually powered backup source of pressurized hydraulic brake fluid to all four of the vehicle brakes in the event of failure of the normal source. During normal braking, fluid from the backup source is redirected from the vehicle brakes to a pedal simulator. The brake system of the invention further diverse arrangements for providing braking in the event of a failure of the normal source of pressurized fluid. The brake circuit for the front wheels are provided with relatively low cost fluid separator units, while the rear brake circuit is not.

Abstract: A vehicle brake apparatus comprises brake operation detecting device for detecting an operation of a brake operating member, a fluid pressure type booster which boosts the operating force applied to the brake operating member, a pressure detecting device for detecting a pressure supplied to the fluid pressure type booster, and an electric motor control device. A recirculating type hydraulic pressure modulator is disposed in a hydraulic pressure conduit between a master cylinder and a wheel brake cylinder. The electric motor control device drives an electric motor for activating a recirculating pump in response to the brake operation detected by the brake operation detecting device and the pressure detected by the pressure detecting means so that the pressure in the wheel brake cylinder is modulated.

Abstract: A pressure sensor module for use in conjunction with an electropneumatic brake, comprising a casing and a plurality of pneumatic input ports on a first face of the casing. Transducers are inside the casing and in communication with its own port. A common electrical connector is positioned on a second face of the casing, and each of the transducers is connected, interior the casing, to the common electrical connector.

Abstract: A braking control device for a vehicle executes braking force distribution (BFD) biased to front wheel, taking into account auxiliary braking control such as Braking assist control to be executed when an abrupt or full braking action is done by the driver. In BFD control, braking force on rear wheels is held at a holding braking force and braking force on the front wheels is incremented beyond braking force requested by a braking action of a driver. After the starting of BFD control, further increase in the braking action is reflected in the front wheel braking force. When the auxiliary braking control is executed, the holding braking force on the rear wheels and the increment of the braking force on the front wheels are determined based upon a demand of the auxiliary braking action as well as the braking action amount by the driver.

Abstract: In a case where a generation of a brake noise is detected at least one of the front and rear wheels on the left side and on the right side, respectively, the vehicle brake system selects a wheel where the generation of the brake noise is detected as a noise generating single-wheel. Then the vehicle brake system reduces target braking force for the noise generating wheel by a predetermined amount, thereby reducing or suppressing the brake noise in the noise generating wheel. At the same time, the vehicle brake system increases target braking force for one of the front and rear wheels which is other than the noise generating wheel by the amount equivalent to the predetermined amount mentioned above. Accordingly, while the deviation of the braking force from the optimal distribution between the front and the rear of the vehicle is reduced, the driver does not feel an unpleasant sensation due to an abnormal vehicle behavior and the like.

Abstract: The invention relates to a method for controlling the supply of a pressure medium on rail vehicles which are coupled together in a tractive link both mechanically and in order to enable the flow of said pressure medium, whereby said pressure medium is supplied by a main air container pipe which extends through all rail vehicles and which is fed with a pressure medium via a plurality of compressors individually mounted in each rail vehicle. The aim of the invention is to allow a balanced use of the compressors included in the tracture link. In order to achieve this, a changeable or fixed order of priority is defined for the compressors according to the total number of compressors in the tracture link, whereby the number of compressors activated depends on the order of priority necessary to meet the actual required amount of pressure medium.

Abstract: The present invention is directed to a hydraulic brake apparatus provided with a pressure source for generating hydraulic pressure, a pressure regulating valve for regulating the hydraulic pressure generated by the pressure source in response to an input state, a master cylinder having a master piston for defining a pressure chamber for receiving therein the hydraulic pressure fed from the pressure regulating valve, and a master chamber for discharging hydraulic braking pressure. And, a pressure supply device is provided for supplying the hydraulic pressure from the pressure chamber into a hydraulic pressure circuit including the master cylinder and the wheel brake cylinder, when the hydraulic braking pressure discharged from the master cylinder is equal to or greater than a first predetermined pressure, and/or when the hydraulic pressure in the pressure chamber is equal to or greater than a second predetermined pressure.

Abstract: Master cylinder pressure generated in a master cylinder is transmitted to wheel cylinders through a linear valve that generates a differential pressure proportional to the amount of current supplied, and respective increase control valves. As a result, a braking force is generated. Brake fluid discharged from the wheel cylinders is, for example, reserved in a pressure regulating reservoir. The brake fluid sucked up from the pressure regulating reservoir by a pump is discharged to the downstream side of the linear valve, and then the fluid is again returned to the pressure regulating reservoir. When existence of brake noise is detected, dither control of the linear valve is executed. By setting a dither frequency to 500 Hz to 1 kHz which is lower than a resonance frequency of a caliper, pulsation for suppressing brake noise can be applied to the wheel cylinder pressure.

Abstract: The system comprises friction brake means for braking the motor, which means are controlled by brake control means for causing braking to take place, means for determining a level of actuation of said control means, and braking management means which, in addition to the friction braking, are suitable for causing progressive hydrostatic braking to take place, thereby causing a decrease to take place in the ratio between the fluid flow rate delivered by the pump and the active cubic capacity of the motor. The system further comprises means for detecting an emergency braking situation or a normal braking situation as a function of the level of actuation of the brake control means. In an emergency braking situation, the braking management means are suitable for successively causing a sudden decrease to take place in the fluid flow rate delivered by the pump, and then causing progressive hydrostatic braking to take place.

Abstract: A multi-cylinder diesel engine provides split mode operation in which one or more cylinders function as air pumps. Compressed air supplied by the cylinders is amplified and stored to a high pressure air tank from which it may be used to run air brakes or other systems. Improved energy density is achieved over prior art vehicle air systems and an auxiliary air compressor is eliminated.

Abstract: A switching reservoir which reserves brake fluid for reducing a pressure to a wheel cylinder is connected to a pressure decrease control valve and an intake port of a pump through a reservoir port, and connected to a M/C through a connection port. There are a ball valve and a rod below the ball valve inside the connection port. The rod moves up and down the ball valve integrally with a piston of the reservoir chamber. When an amount of the brake fluid in the reservoir chamber becomes less than a predetermined amount, the rod moves upward to cause the ball valve separates from a valve seat and is changed to be in an open sate, allowing the brake fluid to flow in from the M/C. Accordingly, the pump is always capable of sucking up the fluid, thereby preventing sharp increase of the rotational speed of the motor due to a sharp decrease in the pump load caused by an empty reservoir chamber and enabling driving of the motor with a duty control. Therefore, low noise and low pulse pressure can be achieved.

Abstract: A hydraulic brake apparatus includes a brake master cylinder having a rod piston moving in response to a brake pedal; a separation valve provided in a hydraulic brake circuit in order to establish and shut off communication between the brake master cylinder and the brake wheel cylinders; a pressure control valve unit for controlling fluid pressure to be supplied from an external fluid-pressure supply source to the brake wheel cylinders while the separation valve is in a shutoff condition; and a stroke simulator mechanism for allowing an idle stroke of the rod piston so as to ensure a stroke of the brake pedal in accordance with an input load to the brake pedal. An orifice is provided in a passage which establishes, during the idle stroke of the rod piston, communication between a pressure chamber and an atmospheric pressure chamber which are defined within the brake master cylinder by means of the rod piston.

Abstract: A brake hydraulic pressure generator is proposed in which the brake stroke fluctuate less when the amount of brake fluid consumed in the wheel brakes fluctuates. Even when the brake pedal force is increased after the brake assisting force has reached its maximum, the reaction force to the pedal force as well as the master cylinder pressure increases corresponding to the increased pedal force. The brake hydraulic pressure generator has a control valve including a spool and a cylinder and adapted to control the hydraulic pressure in a dynamic pressure chamber to a value corresponding to the stroke of an input shaft. It further includes a pressure sensor, a solenoid valve and a fluid chamber.

Abstract: A method and a device for controlling the braking torque of a brake force controller at at least one wheel of a motor vehicle, in which the control pulses for a hydraulic valve is not calculated as a function of the control signal of the hydraulic pump (pump motor PM) but of the actual standstill of the pump motor PM. To detect the actual standstill of the pump motor PM, its induced voltage &mgr;PM is measured. When voltage &mgr;PM falls below a predefined minimum threshold value Vx, then the pump motor PM is assumed to be at a standstill.

Abstract: To monitor the emergency braking capability of an electro-hydraulic braking system (EHBwherein, during normal operation, the brake pressure in the wheel brakes is generated by means of a pressure source comprised of a hydraulic pump, an umulator, and hydraulic valves, and wherein a switch-over to a hydraulic connection between a master cylinder and the wheel brakes is executed in the event of an emergency braking situation. With predetermined events, e.g.

Abstract: A vehicular braking force control apparatus includes a solenoid valve disposed between a master cylinder and the suction side of a hydraulic pump. A ripple absorption low-pressure reservoir is provided between the solenoid valve and the suction side of the hydraulic pump. The low-pressure reservoir is partitioned, by a partition member, into an operation liquid portion that communicates with an auxiliary suction passage and an air portion where air exists. A spring member for pressing the partition member toward the operation liquid portion side is provided in the air portion.

Abstract: A vehicle electro-hydraulic braking system having a fluid pressure accumulator of the pre-charged diaphragm type which is used to store fluid under pressure, charged by means of a fluid pump or compressor driven either by an electric motor or directly from the vehicle engine for supply to a valve system which is adapted to supply the brake or brakes of the vehicle with fluid pressure in accordance with the level of the driver's braking demand, the control of the accumulator pressure being arranged to lie within a fixed control range, with a cut-in pressure defining the lower limiting pressure of the control range and a cut-out pressure defining the upper limiting pressure of the control range, and there being a warning pressure range defined between a warning pressure level and the cut-in pressure, wherein at least one of the warning, cut-in and cut-out pressure levels is arranged to be controlled in dependence upon temperature.

Abstract: A control device for the parking brake of a motor vehicle has a hydraulic cylinder with a piston chamber that can be pressurized by means of a valve arrangement, and has a hydraulic piston connected mechanically to engagement elements of the parking brake. The parking brake is forced into an engaged or disengaged position depending on the hydraulic pressure in the piston chamber. The piston chamber connects to a pressure sensor providing pressure signals that represent the state of the parking brake and that are evaluated by an electrical control unit. The control unit defines a first predetermined pressure threshold corresponding to the engaged state of the parking brake, and a second predetermined pressure threshold corresponding to the disengaged state of the parking brake.

Abstract: A hydraulic drive for a vehicle has a pressure source (7) generating a predetermined pressure for maintaining the operating pressure of a hydraulic motor (5), a braking cylinder (18) with a spring chamber (20) comprising a spring arrangement (19) for operating a braking arrangement (17) and a release chamber (21) that can be acted upon by pressurised fluid from the pressure source (7) against the force of the spring arrangement (19) with the purpose of retaining the braking device (17) in its release position, and comprises a braking control valve (22) that, in a release position, releases a flow from the pressure source (7) to the release chamber (21).

Abstract: In order to improve precision and reliability of a hydraulic pressure control apparatus for a brake system of a vehicle, this invention provides a hydraulic pressure control apparatus for a brake system of a vehicle including a control unit for controlling operation of the hydraulic pressure control apparatus, a pressurized fluid generating unit for pressurizing brake fluid and supplying the pressurized fluid, and a hydraulic pressure distributing unit for mechanically selecting and transmitting at least one of hydraulic pressure of the pressurized fluid supplied from the pressurized fluid generating unit and hydraulic pressure supplied from a master cylinder of the brake system to a wheel brake cylinder of the brake system.