Abstract: The method and system for controllably restricting the on time of a pump of an electro-hydraulic control system for a hydraulic brake system by modeling the amount of hydraulic brake fluid in a low pressure accumulator (LPA) of the hydraulic brake system. Sensors sense wheel speed of their respective wheels of a vehicle. Control valves, including isolation and dump valves, together with the pump, vary the amount of brake fluid in the LPA. A control unit electrically coupled to the pump, the control valves and the wheel speed sensors, initially detects an electro-hydraulic control event based on the sensed wheel speeds and then activates the control valves and pump which vary the amount of brake fluid in the LPA. The control unit models the amount of brake fluid in the LPA during the activation and controls the state of the pump based on the modeled amount of brake fluid in the LPA.

Abstract: A damped piston assembly is configured for use in a vehicle anti-lock braking system pump includes a piston, an insert and an elastomeric annular element. The piston has an axial cavity in a piston end portion. The insert has a cylindrical portion slip fit to the axial cavity of the piston. The insert also has a lip at an insert end portion with a diameter larger than the axial cavity of the piston and less than or equal to an outside diameter of the piston. The an elastomeric annular element is positioned between the lip of the insert and the end portion of the piston. The elastomeric annular element defines a gap between an end of the cylindrical portion of the insert and a bottom of the axial cavity in the piston when the piston is in an unloaded condition.

Abstract: There is presented an anti-lock brake system including a motor and pump assembly for supplying brake fluid to the brake system, the assembly comprising an electric motor, and gear pumps driven by the electric motor and operative to provide the brake fluid under pressure to the brake system.

Abstract: A hydraulic brake circuit is intended for a motor vehicle provided at least with an electrically pilot-controlled braking function, and including at least a master cylinder (1), an electric pump (2), first and second brake motors (3, 4), first and second respective solenoid valves (5, 6), and a low-pressure capacity (7). In addition to a conventional accumulation chamber (8), the capacity (7) comprises an access chamber (13) which interacts with the accumulation chamber (8) to form a simplified distributor which offers additional switching options which can be used for a new braking function.

Abstract: The present invention relates to a brake fluid pressure control apparatus provided with a flow valve which, during the normal operation, when a spool is in the stationary position, a master cylinder communication port is communicated with a wheel cylinder communication port while the pump communication port is closed, and during an antiskid control operation, a pump communication port and a wheel cylinder communication port are communicated, as well as a switching device to switch between the first and the second conditions. In the first condition, a master cylinder communication port is communicated with the output fluid passage of the master cylinder while the communication between the pump communication port and the master cylinder communication port is shut off.

Abstract: A hydraulic unit for wheel slip control, which is located between a master cylinder and wheel brake cylinders. Reflection damping devices are installed in main brake lines located between the hydraulic unit and the master cylinder which damp pressure waves that originate at control valves of the hydraulic unit. When the control valves are triggered in the wheel slip control mode the pressure waves are largely kept away from the master cylinder. By the means of length adaptation of the main brake lines, the brake lines can also contribute to the damping.

Abstract: A hydraulic brake coupled to a rotary shaft including a hydraulic pump connected to the shaft, the pump having a pump inlet, and a pump outlet, a hydraulic loop having an inlet part connected to the pump outlet and an outlet part connected to the pump inlet, a flow control device positioned in the hydraulic loop between the inlet outlet parts for controlling flow of hydraulic fluid in the hydraulic loop, and a brake actuator connected to the flow control device for reducing the flow of hydraulic fluid in response to operation of the brake actuator.

Abstract: A fluid pressure boosting type brake system includes a fluid pressure source including a fluid pump and a pressure tank connected to the pump, and a control valve capable of controlling the output pressure from the fluid pressure source to a fluid pressure corresponding to the degree of brake operation to output it. In this brake system, the fluid pump can be driven in accordance with the consumption of fluid pressure in a brake device, thereby insuring a reliable sufficient fluid pressure in the fluid pressure source.

Abstract: An anti-lock braking system (ABS) pressure modulator is provided. The modulator includes a frame with a bore fluidly exposed to master cylinder and wheel cylinder connections and a check valve for preventing fluid communication from the master cylinder connection to the wheel cylinder connection vi the bore. A piston is slidably mounted within the bore and has a predetermined extreme position at which a stem of the piston opens the check valve. A power device is actuated by an ABS controller. A cam, moved by the power device, has a cam surface. The position of the piston is determined by the cam. A cam follower roller is connected with the piston to in contact with the cam surface. A one-way brake prevents rotation of the roller when the cam moves in one rotational direction to allow the piston to move away from the predetermined extreme position, but allowing the roller to roll over the cam surface when the cam moves in the opposite direction to move the piston toward the predetermined extreme position.

Abstract: A hydraulic brake control system for a vehicle includes a return line for reducing a pressure built up in a wheel cylinder. The return line includes therein a switching valve for opening and blocking the return line. The return line further includes therein cylinders each having therein a piston for defining a piston chamber therein. Each piston has a first state where a brake fluid flowing from the wheel cylinder via the switching valve is allowed to flow into the piston chamber, and a second state where the brake fluid is allowed to be discharged from the piston chamber so as to be returned to a master cylinder. An operation control mechanism is provided for controlling the pistons into the first states and the second states, respectively, at different timings from each other in turn.

Abstract: An hydraulic braking system for a vehicle comprises a pedal-operated combined hydraulic booster and master cylinder assembly (1) for applying a brake (15, 18) on a wheel (16, 19) and having a master cylinder (6) and a servo chamber (7), an auxiliary hydraulic power supply (10) defining a booster pressure in the servo chamber, a flow valve (17, 20) through which fluid is supplied to the brake, and a solenoid-controlled valve (27) for controlling the setting of the flow valve for brake re-application during ABS by the application to it of control fluid from the servo chamber (7) in response to signals from a control module (38).

Abstract: An antilocking brake fluid pressure control unit for a vehicle includes a fluid pressure control device which receives an antilocking operation signal for controlling the pressure applied to a wheel brake. A pump in a parallel flow circuit returns a brake working fluid. A damping chamber (13) is connected to a fluid passage (9) between an outlet port of the pump and a feedback point (15). A filter is provided in the fluid passage (9) between the damping chamber (13) and the feedback point (15). Due to this structure, air bleeding from a brake piping system is simplified when assembling the brake system in a vehicle, and the time needed for charging a working fluid into the brake system is reduced.

Abstract: A brake pressure control system for braking systems of a vehicle with anti-locking and drive slip control in which there is at least one expansion chamber provided between the wheel brake cylinders and the recirculating pump. The expansion chamber includes an inlet and an outlet on the same end with a piston having a closing mechanism thereon that is spring forced to seat the closing mechanism on a seat at the outlet. The valve seat is reduced in size compared with the piston and the spring is in a chamber which is open to the atmosphere. Due to the valve seat being reduced in relation to the area of the piston located in the expansion chamber, a steep closing force gradient is achieved, since even small pressure differences result in large closing force differences, so that the opening and closing pressures lie close together. Based on this additional closing mechanism, provided on the expansion chamber, the requirement for a separate valve for brake pressure control is no longer required.

Abstract: A simplified and improved hydraulic brake system has at least one valve arrangement for the brake pressure modulation in a wheel brake. Furthermore, a high-pressure pump is provided to return pressure medium from the wheel brake into a main brake cylinder in the case of an anti-lock control operation or to deliver pressure medium from the main brake cylinder into a wheel brake during drive-slip control operation. A shut-off valve with a spring-actuated through-flow position and a shut-off position, which can be selected by the pressure at the main brake cylinder end, is arranged upstream on the suction side of the high-pressure pump. The hydraulic brake system with anti-lock and drive-slip control device is used in motor vehicles.

Abstract: A brake fluid distribution control system for use in closed antilocking brake systems includes a switch in communication with low pressure accumulators for cyclically activating pumps that evacuate the low pressure accumulators of brake fluid under desired conditions. The method associated with this invention can be implemented by providing an indicator for indicating the amount of fluid within the accumulator and a switch for cyclically activating the pump when the fluid within the accumulator reaches a preselected capacity level. Alternatively, the antilocking brake system electronic controller is provided with appropriate software for cyclically activating the pump that evacuates the accumulators under preselected conditions.

Abstract: The electrohydraulic or electropneumatic braking-control device for axles of trailers having mechanical brakes includes a hydraulic or pneumatic circuit mounted on the trailer, made up principally of a pressure accumulator, the internal pressure of which is automatically adjusted above a minimum value, as well as of a control gate, the opening of which is proportional to a control current function of the pressure exerted on the brake pedal of the tractor vehicle and of an adjustment carried out as a function of the load of the trailer. In case of attachment parting or of unhitching of the trailer, the disconnection of the connection plug actuates a safety valve that automatically controls the energetic braking of the trailer. The safety valve includes a manual control. It is possible to unbrake, then to rebrake the trailer in order to maneuver it. The trailer braking device may be mounted from the outset or subsequently, requiring only few transformations of the tractor vehicle.

Abstract: A vehicle powered by an electric motor which may be operated as a generator to effect regenerative braking of certain vehicle wheels in combination with individual friction brakes associated with other wheels. A commanded vehicle deceleration is apportioned among the wheels by determining the maximum regenerative braking deceleration achievable by drive wheels, and braking the vehicle occurs solely by regenerative braking so long as the commanded deceleration is less than the determined maximum deceleration. When a commanded deceleration exceeds the determined maximum, the regenerative braking is supplemented with friction braking of the other wheels while the maximum regenerative braking is maintained.

Abstract: According to the invention there is provided a hydraulic brake coupled to a rotary shaft. It includes a hydraulic pump connected to the shaft, the pump having a pump inlet, and a pump outlet, a hydraulic loop having an inlet part connected to the pump outlet and an outlet part connected to the pump inlet, a flow control device positioned in the hydraulic loop between the inlet part and the outlet part for controlling flow of hydraulic fluid in the hydraulic loop, and a brake actuator connected to the flow control device for reducing the flow of hydraulic fluid in response to operation of the brake actuator. The pump is advantageously a gearwheel pump, and may include a gearwheel housing having one side formed as a flow-control plate.

Abstract: Brake fluid pressure control unit improved for smaller size and lower cost. A motor for a pump ms mounted in the circuit block and the pump is mounted on one axial end of the motor. The pressure adjusting units having solenoid valves are arranged around the motor. The case of the motor has a portion forming a part of a magnetic circuit through which magnetic fluxes produced in the coils or the solenoid valves flow.

Abstract: The invention relates to a pressure-regulating device for a hydraulic circuit, especially for a brake circuit of a motor vehicle, comprising at least one source of fluid under pressure (10) connected to a reservoir of fluid under low pressure (16) and, in at least one subcircuit (I, II), a second source of fluid under pressure (50) and two pressure receivers (20, 22). According to the invention, a proportional solenoid valve (24, 26) is associated with each pressure receiver (20, 22) and is connected to the source of fluid under pressure (10) and to the second source of fluid under pressure (50), and a differential pressure/vacuum valve (100) closes, at rest, communication between the source of fluid under pressure (10) and the supply of the second source of fluid under pressure (50), this communication being opened when the second source of fluid under pressure is put into operation.

Abstract: In a hydraulic braking pressure control system comprising a brake device (B.sub.FL, B.sub.FR, B.sub.RL, B.sub.

Abstract: A fluid pressure control system which includes an operational reaction force generating device having a piston which includes a front surface facing a pressure chamber and is operatively connected to an operating member so as to reduce a volume of the pressure chamber in response to the operation of the operating member. The fluid pressure control system further includes a fluid pressure control valve capable of adjusting and outputting an output pressure from a fluid pressure supply source capable of outputting a constant fluid pressure in accordance with the operation amount of the operating member and a stroke accumulator connected to the pressure chamber.

Abstract: A hydraulic brake system is described including a brake slip and/or traction slip control, wherein a pump required herefor is connected in series into the brake conduit through which, in a normal deceleration process, pressure fluid is displaced from the master brake cylinder to the wheel brake. The pump is mounted so that the intake side thereof is in communication with the master brake cylinder and the pressure side thereof is in communication with the wheel brake. Upon commencement of a slip control, the pump drive is turned on. As the master cylinder pressure prevails on the intake side of the pump the pump can very quickly reach the full discharge capacity, thereby enhancing control response of the slip. Moreover, the risk of air being sucked into the brake system is reduced.

Abstract: A hydraulic anti-lock brake system is disclosed in which the pressure in the wheel brakes can be regulated by means of an inlet valve and an outlet valve in response to the wheel rotational pattern. The wheel brake is supplied with pressure fluid out of the pumps through the inlet valve, and pressurized fluid is taken therefrom through the outlet valve. A differential pressure limiter (18) in front of the inlet valve (15) limits the difference in pressure allowed to build up across the inlet valve by closing a valve until a sufficient pressure build up occurs on the wheel brake. This considerably decreases the noise developed during valve operation. A pressure relief valve (30) insures that an evenly high pressure build-up takes place when the inlet valve (15) is closed by opening when a predetermined pressure difference develops across the inlet valve to allow a higher wheel brake pressure to equalize with the pressure upstream from the inlet valve.

Abstract: An anti-locking hydraulic brake system in which the pedal is brought into a variable position during a brake pressure control action. A correcting variable is determined in such a way that any pressure rating in the power chamber is correlated with a position of the power piston, the correlation between the pressure and the position roughly corresponding to the ratio of pressure and position during a noncontrolled braking action.

Abstract: A pump system is disclosed which operates at high efficency in either a high volume, low pressure mode or a low volume, high pressure mode. First and second internal gear pumps are driven by a common drive shaft. The first pump has a smaller displacment than the second pump and both pumps deliver pressurized fluid to a common discharge passage. An unloading valve is operative to dump the output of the second pump in response to fluid pressure in the discharge passage so that it delivers fluid to the load device only when the pressure is below a predetermined value. The unloading valve also performs the function of a low capacity accumulator. A check valve is provided to prevent back flow in the outlet of the second pump.

Abstract: A braking system (8) comprising: a master cylinder (10); rear brakes (12a,b) communicated to the master cylinder (10); front brakes (14a,b) hydraulically isolated from the rear brakes; an isolation valve (16; 16') interposing the master cylinder (10) and the front brakes (14a,b) having a first state communicating the master cylinder to the front brakes and a second state isolating the master from the front brakes and connecting a pump (42) to the front brakes; a motor (44) for powering the pump (42); a reservoir (54) communicated to an inlet of the pump (42); a control unit (40) for causing front brake pressure to follow rear brake pressure comprising: a first pressure sensor (30) for generating a signal indicative of rear brake pressure; electric proportioning device (94) for generating a commanded front brake pressure signal (P.sub.C); a second pressure sensor (32) for generating a signal of actual front brake pressure (P.sub.

Abstract: A fluid leakage preventing device incorporated in a hydraulically-operated system which includes an accumulator for storing a working fluid under pressure, an actuator operated by the fluid supplied from the accumulator, and a control valve having an open position and a closed position for fluid communication and disconnection between the accumulator and the actuator, respectively. The fluid leakage preventing device includes a fluid leakage detector for generating an output signal indicative of the leakage flow of the fluid from said accumulator through the control valve placed in the closed position. The device further includes a valve reciprocating arrangement responsive to the output signal of said fluid leakage detector, for effecting at least one reciprocating movement of a valving member of the control valve.

Abstract: A radial piston pump is described with dual pistons which are slidingly accommodated within a bushing coupled end to end to a valve body. Automatically controlled suction and discharge valves for a pressure chamber are arranged one behind the other in the longitudinal axis of the pump. The pistons are sealed by means of elastomeric seals compressed by an end of the valve body and bushing under pressure of a threaded sealing plug installed in the pump housing. The valves, valve body and bushing form a cartridge separately assembled and installed as a unit in the housing. The threaded sealing plug is formed with a damping chamber for damping of pressure pulsations.

Abstract: A spring-applied, pressure-released parking brake is controlled by an electrohydraulic control system. A solenoid operated parking brake control valve and a manually operated tow control valve control communication between the engine driven pump, the sump, the operator driven pump and the release chamber of the parking brake so that the parking brake can be released and applied during normal operation of the engine driven pump and so that the parking brake can be released by operation of the operator driven pump when the vehicle is shut down. A transport sump valve and an inlet check valve operate to prevent the parking brake from engaging while the vehicle is moving too fast, as a result of operator error, hydraulic failure or electrical failure.

Abstract: The present invention relates to a vehicle equipped with wheels coupled to fluid motors, restrictions being placed on supply or exhaust conduits of the motors. According to the invention, the vehicle comprises front and rear wheels, each coupled to one of the motors, each motor being of a reversible type, while a restriction is placed on the supply conduit of each motor coupled to the rear wheels, another restriction being placed on the exhaust conduit of each motor coupled to the front wheels. One application of the invention is the production of a wheeled vehicle equipped with a simple and efficient anti-skid system for its wheels.

Abstract: A pressure supply system for a vehicle according to the invention incorporates a pump and an accumulator in which an output pressure of the pump is maintained within a prescribed range by controlling the on-off operation of the pump according to the inner pressure of the accumulator. By changing the prescribed range of pressure according to the actual pressure requirement, for instance according to the change in the travelling speed of the vehicle, the burden on the system is reduced. The prescribed range can be changed either by simply changing the upper and/or lower pressure limits at which the pump is deactivated and activated, respectively, or by operating the pump for a prescribed time period which is dependent on the pressure requirement after a certain reference pressure value is reached. Thus, the structure of the fluid pressure system is simplified, and the generation of unnecessary high pressure can be avoided.

Abstract: The present invention is directed to providing an accumulator for pulsation absorption on a feeding passage between a hydraulic pressure generating device and hydraulic pressure booster equipment, and to provide a restriction on a section of the feeding passage between the accumulator and the hydraulic pressure generating device. As the result, the pulsation caused by a pump is reduced by the restriction, and the pulsation thus reduced is absorbed by the accumulator. Therefore, pulsation is effectively decreased by the restriction and the accumulator, and the pulsation transmitted to the hydraulic pressure booster equipment is quite small.

Abstract: A brake pressure control system with an anti-locking control is presented which is operated with hydraulic fluid including a master cylinder and a plurality of valves for the modulation of the hydraulic pressure in the wheel cylinders of the wheel brakes during a brake pressure control mode, and at least one motor-driven pump (48). An axially movable rotor (66) of the motor (14) is furnished with a thrust member (49) which shifts upon motor start up to actuate a control valve. The fluid connection between the master cylinder (37) and the wheel cylinder (43) is thereby interrupted almost instantaneously. Also, by actuating the valve, fluid flows through a flow limiting valve (59), delivered by the pump (48), into the wheel cylinder (43). A rapid pressure reduction is achieved in the wheel cylinder.

Abstract: In an antilock braking system (ABS) operating on the recirculating principle with a static brake circuit and a tandem master cylinder as the brake booster, a control stage is provided in order to lessen the intensity of reaction shocks noticeable at the brake pedal when the antilock control commences. From the onset of a pressure reduction signal, the control stage generates, for at least one brake-pressure control valve of the ABS, an operating voltage for the drive motor of the recirculating pump unit which rises with increasing duration of this signal. After a predetermined rising time, the voltage can reach a maximum value, correlated with maximum speed of the motor, and then is held at this value at least until dying-out, or otherwise rises to that value which is reached within the pressure-reduction signal duration.

Abstract: The proposed brake system eliminates breather bores and central valves in the working pistons of the master brake cylinder and establishes short-term pressure fluid connections between the supply reservoir and the working chambers when the brake is not applied by controlling replenishment valves and outlet valves. Therefore, connection of the supply reservoir to the working chambers of the working cylinder is constituted solely via electromagnetically controllable connections.

Abstract: A hydraulic dual-circuit brake system with an anti-skid system (ABS) and traction control (ASR) for motor vehicles having a four-channel hydraulic unit with four control valves; a return pump with two separate pump elements for each brake circuit; and two-low-pressure reservoirs connected to the inlets of the pump elements. To supply brake pressure in the traction control mode, an additional hydraulic unit is used, which has a precharging pump for feeding brake fluid from a brake fluid tank into each brake circuit containing a driven wheel, and having a valve unit, which in traction control operation disconnects the pump element associated to a brake circuit having at least one driven wheel from the master brake cylinder on the outlet side. For the sake of improved dynamics during brake pressure buildup, a shutoff element, which in traction control operation disconnects the low-pressure reservoir from the precharging pump, is provided between the low-pressure reservoir and the associated pump element.

Abstract: A braking power converter for trucks, busses, trailers, semitrailers and cars as a long-term brake, with oil as the working fluid and an oil cooler, wherein one or more high-pressure reciprocating pumps, which can control the transporting capacity up to zero transport, are driven continuously by the vehicle proportionately to the travelling speed, and an oil flow is compressed to a high pressure of roughly 300 to 900 bar during the braking operation, subsequently relieved of pressure and thereby heated up, after which the heated oil flow is recooled in the oil cooler.

Abstract: A hydraulic pump comprises at least one alternating-cycle piston (20) having a suction phase and a delivery phase, and sliding in a fixed cylinder (22). The pump possesses in addition a nonreturn suction valve (32) placed between a source of fluid under low pressure (28) and a working chamber (30) defined in the cylinder, and a nonreturn delivery valve (34) placed between the working chamber (30) and an output chamber (16) for the fluid under high pressure, connected to an application circuit 10, 12). The output chamber (16) possesses a wall (40) which is movable as a function of the pressure which prevails in the output chamber (16), the movable wall (40) being capable of controlling the locking of the delivery valve (34) in an open position substantially during the greater part of the suction phase when the pressure in the output chamber (16) is greater than a given pressure, in such a way that the suction valve (32) stays closed in a corresponding manner.

Abstract: A brake pressure control apparatus for automotive vehicles with an anti-locking control system (ABS) and/or with a traction slip control system (TSS) is presented. In the inlet line to the wheel cylinder an inlet valve is provided which affords a change-over from an orifice function into a flow limiting valve function at a predetermined wheel cylinder pressure. Flow is initially through an orifice (6) in a control slide valve piston (20), held in its initial position by a prestressing spring (23) acting through an auxiliary piston in engagement with control slide valve piston (20). An increase in pressure in the wheel cylinder (13), also exerted in the wheel cylinder pressure chamber (9), to a predetermined level, causes the auxiliary piston (27) to disengage from the control slide valve piston (20), preventing the force of the prestressing spring (23) from acting on the control slide valve piston (20).

Abstract: A hydraulic system having a pressure generator which is protected against destructive overload. The hydraulic system has a pulsating feeding pressure generator, such as a piston pump, which feeds pressure fluid at high pressure into a damper chamber of a housing. A throttle body having a throttle bore is disposed on the outlet side of the damper chamber. For producing the protective effect, the damper chamber is preceded by a rupture disk communicating with the outlet. The throttle body suitably has a thin-walled portion, embodied as a rupture disk, in which the throttle bore is located. The embodiment described is advantageously usable in hydraulic systems in which pressure fluids are pulsatingly fed at high pressures.

Abstract: A hydraulic braking system having wheel cylinders, a tandem type master cylinder with first and second output ports, a hydraulic pressure transmitting device with a free piston slidably received in a housing with an input chamber located on one side of the free piston connected to the first output port in the master cylinder and an output chamber on the opposite side of said free piston leading to the wheel cylinders. An on-off valve is included, adapted to cut off the communication between a valve chest and the wheel cylinder in response to the hydraulic pressure in a pilot chamber leading to the first output port becoming larger than the hydraulic pressure in the valve chest by at least a given value. A differential pressure generating device is interposed between the second output port and the valve chest to reduce the output hydraulic pressure from the second output port in the master cylinder by a predetermined value to apply the reduced hydraulic pressure to the valve chest.

Abstract: The disc brake (10, 106, 108, 206) with powered integral parking mechanism comprises a twin piston disc brake (106, 108, 206) having a screw member (22, 24; 122, 124; 222, 224) and nut (28, 29; 228, 229) adjuster mechanism. The twin pistons (16, 18; 216, 218) receive service braking hydraulic pressure to effect a service braking application, and also may be displaced mechanically for a parking application by way of the rack (80, 180) and pinion (47, 48; 247, 248) parking mechanism that is operated by hydraulic pressure.

Abstract: An ALC-system of the closed type is provided, with a throttle (27) switched in response to the filling level of the intermediate reservoir (9) inserted into the intake conduit between the intermediate reservoir (9) and a pump (10). This ensures damping of the pressure pulsation of the pedal and further ensures operation of the brake system for traction slip control operation.

Abstract: A brake system (20) comprising: a master cylinder (26) and a pump (12) for selectively pressurizing an associated brake cylinder or cylinders; a motor (14) for powering the pump; a control circuit (16,90) for modulating motor speed in response to a signal indicative of desired braking effort and actual braking effort; and a control valve (30) responsive to master cylinder pressure for controlling pump flow and for permitting the decay of pressure in the brake cylinders.

Abstract: A piston-type pressure accumulator for traction slip controlled brake systems, and a switching arrangement provided therewith. An accumulator piston (2) is hydraulically pressurized through a compression spring (1) and slidingly guided within a housing (4). At least one sealing element (27) is provided at the accumulator piston (2) which separates an accumulator chamber (21) from a spring chamber (24). The compression spring (1) is clamped between a first cap (3) directly contacting and surrounding the accumulator piston (2) and a second cap (5) straddling the housing (4) and the first cap (3), the first cap (3) performing a relative movement within the second cap (5) which is sensed by a control switch (7), charging of the accumulator chamber 21 is controlled by energization of a loading valve (8) and pump (9), in turn controlled by the control switch (7).

Abstract: A method for braking a wheeled vehicle which has at least one adjustable hydrostatic drive unit with a variable displacement pump and a motor and a driving engine wherein the vehicle driving engine absorbs a drag moment and the kinetic energy of the vehicle is partially reduced hydraulically after the maximum drag moment which is absorbable by the vehicle driving engine is exceeded. In the method positive hydraulic braking is achieved when a limiting rpm of the driving engine is exceeded and the vehicle is braked to a speed at which the incline output power is less than or of the same magnitude as the drag power which is absorbable by the driving engine.

Abstract: A brake control device for vehicles includes a master cylinder, a plurality of wheel cylinders, and an anti-lock control apparatus disposed between the master cylinder and the wheel cylinders of at least one hydraulic circuit. The anti-lock control apparatus includes a hydraulic pump, a reservoir and a changeover device which is selectively changed over at least between a first condition which permits an increase in the hydraulic pressure of the wheel cylinders of at least one hydraulic circuit and a second condition which permits an decrease in the hydraulic pressure of the wheel cylinders of at least one hydraulic circuit in response to the locking condition of the road wheels.

Abstract: The ABS pump output pulsation dampening device (59) comprises a body (10) having disposed therein a pressure source (12) communicating with an inlet line (14) that transmits pressure to an outlet line (16) via an accumulator or storage chamber (20). The body (10) receives at an open end (13) a spring (38) operated accumulator (30) having an accumulator piston (36) received within said accumulator chamber (20). One end (50) of the accumulator piston (36) includes an interior opening (32) which receives slideably and with clearance a dampening piston (60) and a resilient member (62) which biases the dampening piston (60) into engagement with a seat (15) at the end of the inlet line (14). The dampening piston (60) includes an orifice (64) at an one end (63) adjacent the seat (15) and which communicates with a passage (65) extending through the dampening piston (60).

Abstract: A hydraulic braking system includes a master cylinder having a bore with an opening and a closed wall at opposite ends. At least one piston is slidably fitted in the bore and operatively connected to a brake pedal and at least one pressure chamber is defined in the bore by the piston and in communication with wheel cylinders of the vehicle. A normally open valve is associated with the piston so as to close a passage communicating between a reservoir and the pressure chamber when the piston is moved in response to the depression of the brake pedal. A hydraulic booster actuates the master cylinder in response to depression of the brake pedal, and an interrupting device interrupts the communication between the pressure chamber and the reservoir before the normally open valve closes the passage means and is interposed between the pressure chamber and the reservoir. Thereby, the idle stroke of previous master cylinders is eliminated.