Abstract: A brake control system for a vehicle, the brake control system including a master cylinder, a brake line for communicating brake fluid between the master cylinder and a brake, a fluid reservoir in fluid communication with the brake line during non-braking conditions, and means for selectively moving brake fluid into and/or out of the fluid reservoir. The means for selectively moving brake fluid into and/or out of the fluid reservoir includes means for removing gas from the fluid reservoir, and is configured to move brake fluid into the fluid reservoir, so that brake fluid is moved along the brake line in a direction towards the master cylinder, during non-braking conditions. Upon receiving a signal of an anticipated brake event, brake fluid may also be moved out of the fluid reservoir, so that brake fluid is moved along the brake line in a direction away from the master cylinder.

Abstract: An actuation device for a hydraulic actuation system, e.g., a motor vehicle brake or an electrified clutch actuator, may include a connection for an actuation device; a pressure supply device, driven by an electromotor drive, in the form of a piston or double-stroke piston pump; a piston cylinder unit that may be actuated by means of the actuation device; and an electronic control unit. An axis of the piston cylinder unit and an axis of the pressure supply device may be arranged in parallel.

Abstract: The present invention relates to an electrohydraulic braking-force generation device and to a method for operating an electrohydraulic braking-force generation device. The electrohydraulic braking-force generation device comprises: a power transmission assembly that is coupled to a brake pedal; a brake cylinder assembly that is to be actuated by the power transmission assembly, the brake cylinder assembly having a first cylinder-piston assembly and said first cylinder-piston assembly being designed to be fluidically coupled to at least one brake circuit; and a brake booster assembly comprising a second cylinder-piston assembly and at least one electromechanical actuator. The brake booster assembly is configured to apply hydraulic pressure to the brake cylinder assembly in order to boost the braking power and the power transmission assembly is configured to actuate the brake cylinder assembly, in each operating mode of the braking-force generation device, by means of a relative movement.

Abstract: To provide a vehicle provided with a valve-stop-mechanism-equipped internal combustion engine capable of ensuring a negative pressure in a brake booster while preventing with reliability fresh air from flowing into a catalyst during a valve stop control. An internal combustion engine provided with a valve stop mechanism capable of changing the operational state of an intake valve between a valve operating state and a valve closed/stopped state is provided. A brake booster is provided capable of assisting operation of a brake pedal of the vehicle. Exhaust side negative pressure passages are provided as communication passages that are configured to be in communication with each branch pipe section of an exhaust manifold in a period in which a negative pressure is generated in the case where the intake valve is in the valve closed/stopped state while an exhaust valve is allowed to open and close. The remaining end of the second exhaust side negative pressure passage is connected to the brake booster.

Abstract: A hydraulic brake apparatus includes a master cylinder pressurizing brake fluid in a pressure chamber and outputting a hydraulic pressure to a wheel cylinder of a first brake circuit, and a pressure control valve controlling a hydraulic pressure of an auxiliary hydraulic pressure source outputting the controlled hydraulic pressure to a wheel cylinder of a second brake circuit, wherein a master cylinder piston includes a first passage which hydraulically connects the pressure chamber and a reservoir, and a switching valve which closes and opens the first passage, and wherein a throttle means and a check valve, which allows the brake fluid to travel only from the reservoir to the pressure chamber, are hydraulically provided in parallel with each other at the first passage at a position between the switching valve and the reservoir.

Abstract: A brake apparatus includes: a master cylinder that forms a driving fluid pressure chamber, which drives master pistons as brake fluid is supplied and discharged; a pressure adjusting part adjusting a driving fluid pressure of the driving fluid pressure chamber; a reaction force generator that forms a reaction force chamber and that is configured to generate a reaction force fluid pressure in the reaction force chamber in accordance with an operating amount of the brake operation member; a brake fluid path, which connects the reaction force chamber to the driving fluid pressure chamber, and a valve device configured to block, at a current-on state, flowing of the brake fluid, and that communicates, at a current-off state, the reaction force chamber to the driving fluid pressure chamber through the brake fluid path to enable the flowing of the brake fluid.

Abstract: A brake system includes a main brake cylinder and a pedal decoupling unit provided with a holding piston, the first ring surface thereof together with a first primary brake cylinder piston defining a first hydraulic chamber that is hydraulically pressurized with an electrically controllable pressure supply device. In order to improve the pedal characteristics of the brake system, in particular in a brake-by-wire brake system, the holding piston is embodied as a differential piston, the second ring surface thereof defining a second, blockable hydraulic chamber, and a piston effect in the second chamber corresponds to a force that acts counter to the direction of actuation on the holding piston.

Abstract: A vehicle braking apparatus includes: a control piston configured to operate so that a reaction force based on the fluid pressure of the boosted fluid pressure application chamber is balanced with a braking operation input from the brake operation member; an elastic member including: a first face adapted to contact with a simulator piston connected to the brake operation member and slidably accommodated in the control piston; and a second face; a sliding member adapted to contact with the second face, the sliding member being accommodated in the control piston; a spring disposed between the sliding member and the control piston; and an odd-shaped portion disposed on at least one of the first and second faces of the elastic member, the odd-shaped portion configured to increase a contacting area of the elastic member and at least one of the simulator piston and the sliding member.

Abstract: A brake booster wherein second and third pistons are separated within a bore of a master cylinder to define second and third chambers. Compensation valves control the flow fluid from a reservoir to the bore while a passage in the second piston connects the second chamber with the third chamber that is connected to the reservoir through an tilt valve that is held opened by pressurized fluid acting on a fourth piston. A control valve responds to a resiliently applied force from an input rod carried by the third piston to supply pressurized fluid to the brake system. In an event pressurized fluid is unavailable, a spring moves the fourth piston and a sixth spring to moves the tilt valve against a seat to seal the third chamber and create a hydraulic lock. Further movement of the third piston correspondingly moves the second piston to effect a manual brake application.

Abstract: A braking system having a master cylinder to which wheel brake circuits (I, II) can be connected, a first piston coupled to a brake pedal, a second piston by means of which the master cylinder is actuated, a third piston actuated by the first piston and connected in a force transmitting fashion to the second piston, a simulation device which gives the driver of the vehicle a pedal sensation, an intermediate space between the second piston and third piston, a pressure generating device which controls the pressure in the intermediate space, a pressure medium reservoir vessel which is under atmospheric pressure and which can be connected hydraulically to the intermediate space, and means for electrically controlling the pressure in the intermediate space.

Abstract: A pressure regulating valve unit 7 is configured to be electrically driven according to a detection value of a detection unit 74 adapted to detect an amount of brake application effort made by a brake operation member 5 so as to switch states of the vehicle brake apparatus between a state where a boosted hydraulic pressure chamber 9 is made to communicate with a hydraulic pressure generating source 6 while a communication between the boosted hydraulic pressure chamber 9 and a reservoir R is interrupted, a state where the communication between the boosted pressure chamber 9 and the hydraulic pressure generating source 6 is interrupted while the boosted pressure chamber 9 is made to communicate with the reservoir R, and a state where the boosted hydraulic pressure chamber 9 is disconnected from both the hydraulic pressure generating source 6 and the reservoir R.

Abstract: A brake fluid pressure control device for a bar handle vehicle has a front wheel brake system which imparts a braking force to a front wheel and a rear wheel brake system which imparts a braking force to a rear wheel. At least one of the brake systems has a master cylinder which generates brake fluid pressure in accordance with an operation amount of a brake operation element, first and second wheel cylinders both of which impart the brake force on one of the front and rear wheels, a first hydraulic path which communicates the master cylinder with the first wheel cylinder, a second hydraulic path which is branched from the first hydraulic path and connected to the second wheel cylinder and a boosting unit which boosts the brake fluid pressure in the second wheel cylinder without boosting the brake fluid pressure in the first wheel cylinder.

Abstract: In a dual-circuit hydraulic motorcycle brake system with two hand or foot-operated master cylinders, at the commencement of the pump operation in one of the brake circuits, the change-over valve (20) and/or the separating valve (19) of that brake circuit assume a switching position in which the pressure which can be generated by the pump (9) is prevented from causing a reactive effect on the associated hand-operated or foot-operated master brake cylinder (7, 13). To this end, the separating valve (19) in the brake line may be switched to a closed or throttling position, while the change-over valve (20) in the suction path is closed. Alternatively, both the change-over valve (20) and the separating valve (19) can be opened at the same time so that the pump conveys brake fluid in a circle.

Abstract: A brake apparatus capable of applying a regulator pressure regulated by a regulator valve device to an assisting chamber, to obtain a smooth brake feeling, even when a brake pedal is operated by a vehicle driver, during an automatic braking operation. A first control valve is disposed in a power pressure passage for controlling hydraulic pressure in the assisting chamber to be increased. A changeover valve device is disposed in a regulator pressure passage for selecting either one of a communicating state and a shutting-off state of the passage. A second control valve is connected to the regulator pressure passage between the changeover valve device and the assisting chamber, and controls the hydraulic pressure in the assisting chamber to be decreased.

Abstract: A normally closed secondary solenoid opening/closing valve 36 is provided along a secondary branched fluid pipe 35 establishing a communication between an accumulator 11 and a reservoir 8 through a fluid pressure input side to a fluid pressure output side of a regulator valve 3, and in the event that a fluid pressure supplied to the regulator valve 3 decreases down to or lower than a predetermined range due to something abnormal occurring in the accumulator 11, the state of the secondary solenoid opening/closing valve 36 is changed over from a closed state to an opened state, whereby a residual pressure in the accumulator 11 and a residual pressure in the output fluid pressure chamber 15 can be released through the reservoir 8 which is in communication therewith through an output fluid pipe 31 and the secondary branched fluid pipe 35 along which the secondary opening/closing valve 36 is provided.

Abstract: The present invention is directed to a braking stroke simulator for use in a brake system, which comprises a simulator piston moved in response to operation of a manually operated braking member, and an elastic element for providing a stroke to the simulator piston in response to braking operation force applied to the manually operated braking member, wherein restoring amount of the elastic element is restricted to set an initial load to be applied thereto. The elastic element includes a first elastic member made of rubber, and a second elastic member made of a helical spring, which is disposed in series with the first elastic member. The initial load applied to the first elastic member and the initial load applied to the second elastic member are set to be substantially equal to each other.

Abstract: A braking system includes a brake actuator which is moveable in a first direction to cause a brake applying member to apply a braking force to a member to be braked. A master valve includes a piston assembly which upon operation of a brake operating member, directs the hydraulic fluid under pressure to the brake actuator to apply the brake. A charging valve is operable in first and second states. The master valve piston assembly includes a pair of coupled pistons separated by a chamber. In a first state, the charging valve connects a source of pressurized hydraulic fluid to the master valve chamber to move the pistons apart, directing a volume of hydraulic fluid to the brake actuator. In a second state, the charging valve connects the chamber to a lower pressure area to allow the pair of pistons to be moved towards one another by a restoring force.

Abstract: A simulator piston is slidably fitted in a control piston to form a stroke liquid chamber between itself and an end wall of a control piston. A port which is closed at a forward limit of the control piston with respect to a backup piston is provided in the end wall of the control piston. A first reaction piston which constantly abuts against the end wall of the control piston and a second reaction piston which abuts against the end wall of the control piston when the control piston advances toward the backup piston through a predetermined travel distance or more, are relatively slidably mounted on the backup piston so that hydraulic pressure of the boosted hydraulic pressure chamber acts on their front ends. Thus, it is possible to curb increase in a stroke and reaction of a brake operating member which would be invalidated by a brake stroke simulator when a hydraulic power source fails, and avoid insufficient strokes of the brake operating member even if spikes are inputted.

Abstract: A hydraulic brake system includes a hydraulic accumulator that stores much of the energy generated upon brake pedal depression. The stored energy can be used to maintain the brakes in their fully engaged state and to help return an applied brake pedal to its released position, in which case return fluid flow to the master cylinder is damped to avoid undesirable severe kickback of the brake pedal. A booster is provided to automatically boost the energy storage capacity of the accumulator during normal brake and hold cycles in order to provide sufficient energy accumulation to compensate for relatively severe pressure drops occurring, e.g., during prolonged periods of storage at extremely low temperatures. The booster may comprise an indexing arm that is acted upon by the system's brake pedal to selectively move a variable thickness spacer on the indexing arm into and out of engagement with the accumulator.

Abstract: A hydraulic brake system includes a hydraulic accumulator that stores much of the energy generated upon brake pedal depression. The stored energy can be used to maintain the brakes in their fully engaged state and to help return an applied brake pedal to its released position, in which case return fluid flow to the master cylinder is damped to avoid undesirable severe kickback of the brake pedal. A booster is provided to automatically boost the energy storage capacity of the accumulator during normal brake and hold cycles in order to provide sufficient energy accumulation to compensate for relatively severe pressure drops occurring, e.g., during prolonged periods of storage at extremely low temperatures. The booster may comprise an indexing arm that is acted upon by the system's brake pedal to selectively move a variable thickness spacer on the indexing arm into and out of engagement with the accumulator.

Abstract: A hydraulic brake system includes a hydraulic accumulator that stores much of the energy generated upon brake pedal depression. The stored energy can be used to maintain the brakes in their fully engaged state and to help return an applied brake pedal to its released position, in which case return fluid flow to the master cylinder is damped to avoid undesirable severe kickback of the brake pedal. A booster is provided to automatically boost the energy storage capacity of the accumulator during normal brake and hold cycles in order to provide sufficient energy accumulation to compensate for relatively severe pressure drops occurring, e.g., during prolonged periods of storage at extremely low temperatures. The booster may comprise an indexing arm that is acted upon by the system's brake pedal to selectively move a variable thickness spacer on the indexing arm into and out of engagement with the accumulator.

Abstract: A brake booster amplifies driver brake pedal input into an output force and travel for operating a master cylinder. A power unit builds and stores high pressure fluid to provide boost. Inlet and outlet solenoid valves regulate pressurized fluid to the amplifying mechanism. In one embodiment, a single boost chamber provides fluid pressure to operate the master cylinder and to provide a brake pressure indicative opposing force to driver input. One travel sensor monitors the position and movement of an input rod and piston, and a second travel sensor monitors the position and movement of an output piston. An ECU monitors system parameters and controls a motor pump, inlet and outlet valves and peripherals. In another embodiment, the opposing force to the brake pedal input is provided by a separate pressure fluid chamber located within and movable with the output piston. Boost chamber pressure and, optionally, output piston travel are monitored to provide a braking force indication.

Abstract: A hydraulic brake valve comprising a body, a passageway defined in the body, an inlet to the passageway, an outlet from the passageway and a movable valve member in the passageway, the valve member is movable between a first position blocking the passageway to prevent communication between the inlet and the outlet, and a second position opening the passageway to allow communication between the inlet and the outlet in response to a pressure differential exceeding a predetermined value. The valve member remains in its second position once it has been moved to its second position.

Abstract: A brake assembly is provided for implementation with a brake system and includes a support bracket, a master cylinder supported by the support bracket and operable to provide hydraulic pressure to the brake system, an accumulator piston extending from the master cylinder and operable to maintain hydraulic pressure within the hydraulic brake system, and an accumulator assembly extending from the support bracket. The accumulator assembly includes a compression plate engaging the accumulator piston, an end cap and an accumulator spring disposed between the compression plate and the end cap, biasing the compression plate against the accumulator piston. A booster arm is pivotally supported by the support bracket and is actuable between first and second positions. In the first position the booster arm limits axial movement of the compression plate against the accumulator piston and in the second position the booster arm permits increased axial movement thereof.

Abstract: A hydraulic pressure control device is provided in which a proportional pressure control valve is actuated by operating the brake pedal to adjust the hydraulic pressure supplied from a pressure source to the wheel brakes to a value corresponding to the pedal operating amount. Also, a brake device for a vehicle using it is provided. The proportional pressure control valve is integrated with a hydraulic pressure generator to transmit the input from the brake pedal to a spool valve in the control valve through a first piston, first spring, second piston and second spring of the hydraulic pressure generator. If the pressure source or the wheel brakes in a first line fail, after the second piston has made a full stroke, brake fluid in a fluid chamber is pressurized, so that the hydraulic pressure generated is supplied to wheel brakes in a second line through a copy valve which is open.

Abstract: A hydraulic brake system includes a hydraulic accumulator that stores much of the energy generated upon brake pedal depression. The stored energy can be used to maintain the brakes in their fully engaged state and to help return an applied brake pedal to its released position, in which case return fluid flow to the master cylinder is damped to avoid undesirable severe kickback of the brake pedal. A booster is provided to automatically boost the energy storage capacity of the accumulator during normal brake and hold cycles in order to provide sufficient energy accumulation to compensate for relatively severe pressure drops occurring, e.g., during prolonged periods of storage at extremely low temperatures. The booster may comprise an indexing arm that is acted upon by the system's brake pedal to selectively move a variable thickness spacer on the indexing arm into and out of engagement with the accumulator.

Abstract: A hydraulic brake booster (12) for use in a brake system (10) having a first housing (100) with a first bore (102) separated from a second bore (104). The first bore (102) retains a power piston (118) and the second bore (104) retains a control valve arrangement (170). A push rod (30) of an input arrangement (49) is connected to the power piston (118) and linked to the control valve arrangement (170) by a lever arrangement (50). A second housing (200) encloses the control valve arrangement (170), lever arrangement (50) and a projection (117) that extends from the power piston (118) to define a cavity or relief chamber (202) having a permanent low pressure. The input arrangement (49) supplies the control valve arrangement (170) with an input force in response to a braking force applied to the push rod (30) to regulate the communication of pressurized supply fluid from the second bore (104).

Abstract: A hydraulic pressure intensifier for operating a vehicle braking system under conditions that are not conducive to the proper operation of a power assist for the braking system. The hydraulic pressure intensifier has an intensifier inlet fluidly connected to a master cylinder and an intensifier outlet fluidly connected to a wheel cylinder. A bypass valve has an input and output fluidly connected to the intensifier inlet and the intensifier outlet, respectively. With normal power assisted braking operation, the bypass valve is open and the master cylinder is fluidly connected to the wheel cylinder via the bypass valve. In a manual or nonpower assisted braking operation, the bypass valve is closed; and the hydraulic pressure intensifier is fluidly connected between the master cylinder and the wheel cylinder.

Abstract: A hydraulic braking pressure generating apparatus for a vehicle includes a hydraulic pressure generator for generating a predetermined hydraulic pressure irrespective of a braking operation of a brake operation member and for outputting the predetermined hydraulic pressure, an input member moved in response to the brake operation member, a first elastic member for transmitting a brake operation force applied to the input member and for applying a stroke corresponding to the brake operation force to the input member, a regulation valve connecting to the first elastic member and for regulating the outputted hydraulic pressure of the hydraulic pressure generator in response to the brake operation force transmitted through the first elastic member and for outputting a regulated hydraulic pressure and a second elastic member connecting the regulation valve and for urging the regulation valve toward its initial position.

Abstract: A hydraulic pressure intensifier for operating a vehicle braking system under conditions that are not conducive to the proper operation of a power assist for the braking system. The hydraulic pressure intensifier has an intensifier inlet fluidly connected to a master cylinder and an intensifier outlet fluidly connected to a wheel cylinder. A bypass valve has an input and output fluidly connected to the intensifier inlet and the intensifier outlet, respectively. With normal power assisted braking operation, the bypass valve is open and the master cylinder is fluidly connected to the wheel cylinder via the bypass valve. In a manual or nonpower assisted braking operation, the bypass valve is closed; and the hydraulic pressure intensifier is fluidly connected between the master cylinder and the wheel cylinder.

Abstract: A braking pressure generating apparatus for a vehicle includes a hydraulic pressure generator for generating and outputting a power pressure irrespective of an operation of a brake pedal, and an input member connected with the brake pedal. A regulation valve is disposed coaxially with the input member to regulate the power pressure outputted from the hydraulic pressure generator to a predetermined pressure corresponding to the braking operation force of the brake pedal and output the predetermined pressure. The regulation valve includes a body and a valve portion movably disposed in the body. A force distribution device is disposed between the input member and the regulation valve to the distribute braking operation force applied to the input member the valve portion and the body of the regulation valve.

Abstract: A spool-out type booster brake valve device for industrial vehicles is configured to allow hydraulic working fluid to be supplied not only to a booster chamber but also to a master chamber thereby eliminating the need to use a separate brake fluid reservoir tank for supplementing brake fluid in the master chamber. The brake valve device is used in an industrial vehicle equipped with a fluid pump, a reservoir tank and a brake actuator. The brake valve device includes a valve body having an inlet port, a drain port, a brake port, a booster chamber communicatable with the pump via the inlet port and a master chamber communicatable with the brake actuator via the brake port. The master chamber is connected to the inlet port to receive working fluid from the pump. A valve spool is slidably fitted in the valve body through the booster chamber and the master chamber, the valve spool being shifted between an idle position and an operating position.

Abstract: A hydraulic brake booster includes a primary master cylinder M1, a hydraulic power source 5, a fluid tank 11 and proportional booster valves Vf, Vr for boosting an output hydraulic pressure from the primary master cylinder M1 proportionally so as to supply the hydraulic pressure so boosted to wheel brakes Bfa, Bfb, Bra, Brb, the proportional booster valves being constructed as a spool type proportional booster valve.

Abstract: Disclosed herein is an improved braking system. The braking system includes a valving arrangement which reduces the dead band of the system and the freedom to randomly select the pistons return position. In particular, the system includes a fluid reservoir, a piston located in a cylinder including a reservoir port, a first fluid channel connecting the reservoir to the reservoir port, a brake actuator, and a second fluid channel connecting the cylinder to the brake actuator. The piston is moveable within the cylinder to produce fluid flow within the first channel. A first valve is disposed between the reservoir and the cylinder to prevent fluid flow from the cylinder to the reservoir when the piston is moved to pressurize fluid in the second fluid channel.

Abstract: A plurality of electrical fluid pressure control valves or a plurality of groups each comprised of a plurality of electrical fluid pressure control valves are operatively associated with respective power supply replays. The electrical fluid pressure control valves and a plurality of electrical switch valves are connected in parallel to a power source. A plurality of failure sensors are associated with the respective electrical fluid pressure control valves or the respective groups so as to detect whether an electrical system failure in any one of the electrical fluid pressure control valves or the groups occurs. If occurs, failure control unit is operable to control a corresponding one of the power supply relays so as to cause a corresponding one of the electrical switch valves to selectively connect a corresponding one of the wheel cylinders to a master cylinder.

Abstract: A control valve assembly for a total pressure hydraulic brake is provided with an input port, and output port, a remote control input port connected to a hydraulic fluid supply, a first response which is moved together with depression of a brake pedal, a second response which is moved by the hydraulic fluid flowing through the remote control input port, and a control valve which operates in accordance with the movement of either the first or the second response. The control valve supplies the hydraulic fluid from the input port to the output port in response to the hydraulic fluid flowing through the remote control input port, as well as the depressing force exerted on the brake pedal.

Abstract: A brake device has a static pressure line for generating brake fluid pressure in at least one line by manual operation, a dynamic pressure source such as a power pump, an electronic control unit, a stroke sensor for detecting the control input of the manual operation, a unit for measuring or estimating the vehicle deceleration, a first control valve adapted to alternately supply and not supply pressure fluid from the dynamic pressure source to the static pressure line, and a second control valve adapted to alternately discharge and not discharge pressure fluid from the static pressure line to a reservoir.

Abstract: An electronically controlled brake device for controlling a brake pressure according to a manual input. While the dynamic pressure line is functioning normally, the dynamic pressure acts on one end of a push rod associated with a brake pedal to give such a force as to counteract the control input to the brake pedal. If the dynamic pressure line fails, the push rod comes into contact with a dynamic pressure piston to transmit the control input force to a master cylinder. An electronic pressure control valve is provided to adjust the connection of the dynamic pressure source with a reservoir and with a dynamic pressure chamber in response to the commands of an electronic control unit so that its output pressure will be in a predetermined relationship with the pedal stroke. Thus in normal conditions, a desired deceleration is obtained with a shorter pedal stroke and in the failure of dynamic pressure, a minimum deceleration is obtained with a lighter pedal force.

Abstract: A slip-controlled hydraulic brake system with improved operational reliability during the slip control phase of operation has a master cylinder having shortened overall axial length. The master cylinder includes a valve-opening mechanism of one central control valve supported on the bottom of the longitudinal bore of the master cylinder, and the valve-opening mechanism of another central control valve supported on the secondary piston wherein during a slip control action, in the presence of a predetermined travel of the pistons of the master cylinder, a force component is generated that increases the reliability of the opening of the central control valves.

Abstract: A brake system having a master brake cylinder with at least one piston in a stepped bore in which the piston is acted upon at one end by a piston rod and on the other end defines a pressure chamber, from which an outlet or a brake line leads to wheel brake cylinders of at least one brake circuit. The pressure chamber, or the brake line discharging from this pressure chamber communicates on the one hand with a compensation chamber and on the other with an annular chamber, the volumes of both these chambers being variable contrarily by movement of the piston. The connection between the pressure chamber and the compensation chamber is interrupted by a valve, and a connection is then established with a fluid reservoir. A suitable amount of fluid can then be transported from this fluid reservoir into the compensation chamber by means of a return pump.

Abstract: A clutch booster control system having parallel booster cylinder and a control valve, the booster cylinder having an extendible rod and being operatively connected between the vehicle frame and the clutch operating lever, the control valve having a slidable piston and being connected between the clutch operating lever and the pedal linkage. Movement of the clutch pedal moves the control valve piston to provide air to the booster cylinder for operating the clutch operating lever.

Abstract: A cylindrical casing accommodates an operator pistion and a power piston separated by a fixed barrier which serves to define with the former a reservoir and with the latter a power chamber. A piston rod affixed to the operator piston extends through the barrier into manual brake actuating relation with the power piston. Hydraulic fluid under pressure is introduced to the reservoir from which it flows through barrier passages, past a check valve, into the power chamber and out through venting ports formed in the piston rod. To apply vehicle brakes linked to the power piston, the operator piston is manually propelled toward the barrier, and the power piston is thus forced away from the barrier by the piston rod, resulting in rapid transfer of hydraulic fluid from the reservoir to the power chamber. The venting ports then close, such that the power chamber is pressurized to exert a brake power assisting hydrostatic force on the power piston.

Abstract: A brake unit for a road vehicle with a hydraulic dual-circuit brake system having two master cylinders, the brake booster and elements for antilock and/or propulsion or slip control in a common housing. A brake booster drive cylinder which can be subjected to the outlet pressure, proportional to the pedal travel, of a brake valve, is arranged between static master cylinders. Coupled to the piston of the drive cylinder is a pivotable rocker, the arms of which are each supported on one of the master cylinder pistons via tappet. Assigned to at least one of the master cylinders is a regulating cylinder having an opposed piston which can be supported on the piston of the master cylinder and which, when subjected on one side to the outlet pressure of the auxiliary pressure source of the brake booster, causes the piston of the master cylinder to be returnable towards its basic position counter to the actuating force exerted on it.

Abstract: A hydraulic brake system (FIG. 2) composed of a master cylinder (30) coupled to the brake pedal (46), wherein there is provided a hydraulic booster (31) with a booster piston (91) and a booster chamber (35), and an auxiliary pressure proportional to the pedal force (F) develops in the booster chamber (35) during braking by way of a brake valve (6) actuated by the brake pedal (46). With the booster (31) intact, the auxiliary pressure prevailing in the booster chamber (35) acts by way of a pressure line (85, 87) on the two-stage piston (20) of a fast-fill cylinder (18), whose small stage (95) is immersed into a filling chamber (22) and, during the brake action, presses the pressure fluid available in the filling chamber (22) by way of pressure line (33) into the one brake line (37) connected to the working chamber (34) of the master cylinder (30).

Abstract: A hydraulic dual-circuit tandem master brake cylinder intended for use in brake systems of motor vehicles is proposed, to which a closed brake circuit (I) and an open brake circuit (II), the latter reinforced by auxiliary pressure, are connected. In order to switch the control valve, the main brake cylinder has a foot-actuated push rod as an actuation member, with transmission of force via a control contour or a travel-limiting spring, and it furthermore has an auxiliary piston member near the pedal, this member having an effective surface for making the feedback of the brake pressure which has been established perceptible. In this manner, a small, compact master brake cylinder construction which is very favorable in price is created. It is furthermore of advantage that the pedal characteristic is designed optimally in terms of human engineering. The main cylinder can also be used at little expense for an anti-wheel-lock apparatus as well.

Abstract: A brake pressure modulating control valve for a hydraulically operated brake system. The control valve includes a spool associated with an air spring chamber. The system includes equipment for modulating the air pressure in the air chamber for constantly and concurrently modulating the pressure of the hydraulic fluid in the brake system.