Abstract: A multi-way valve includes a control pressure channel, first and second control fluid channels, a valve body in the first and second control fluid channels, and an electrically controlled device having a drive member and an armature. The armature moves back and forth by the drive member between inactive and active positions. Movement of the armature from the inactive to the active position displaces the valve body arrangement to an active position, closing the first and opening the second control fluid channel is open. The electrically controlled device includes a drive body connected to the armature and a first spring member between the armature and the drive body. The valve body arrangement is biased towards the inactive position by a second spring member. The armature in the inactive position is biased towards the active position by a third spring member. Also disclosed is an actuator including the valve.

Abstract: Pneumatic control valve of a vehicle air brake system, having at least one first valve system which is arranged in a housing upper part with a first valve piston which can be actuated via an elastomer spring element, and having a second valve system which is arranged in a housing lower part with a coaxially arranged second valve piston which can be actuated by the first valve system and with a second annular plate valve. The elastomer spring element and the first valve piston are configured in one piece as a composite component. In the region of a radial sealing lip of the spring element, the material of the elastomer spring element engages radially and axially in a positively locking manner around a radially outer section of the first valve piston.

Abstract: Pneumatic control valve of a compressed-air brake system of a vehicle, having at least one first valve system which is arranged in an upper housing and has a first valve piston which interacts with a first valve and can be actuated manually or by means of an actuator via a spring element by means of a plunger piston, having a second valve system which is arranged in a lower housing with a coaxially arranged second valve piston which can be actuated pneumatically and/or mechanically by the first valve system and with a second annular plate valve. The first valve piston is guided via the plunger piston in the cylindrical guide in the housing upper part.

Abstract: A foot brake valve apparatus is provided for a heavy vehicle braking system. The foot brake valve apparatus comprises a valve body having a first side face and a second side face opposite the first side face. The apparatus further comprises a primary supply pressure port associated with a primary braking circuit and adjoining the first side face, and a primary delivery pressure port associated with the primary braking circuit and adjoining the first side face. The apparatus also comprises a secondary supply pressure port associated with a secondary braking circuit and adjoining the first side face, and a secondary delivery pressure port associated with the secondary braking circuit and adjoining the first side face.

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

Abstract: A control device (10) for a brake-power-assisted brake system of a vehicle having a first input device (26) for a supplied first information item (28) relating to a supplied assistance force (Fu) of a brake booster (14) of the brake-power-assisted brake system, a second input device (30) for a supplied second information item (32) relating to a total force (Fg) comprising the assistance force (Fu) and a driver braking force (FI) supplied by activation of an activation element (12) of the brake-power-assisted brake system, an evaluation device (36) which is configured to define a third information item relating to a proportional relationship between the total force (Fg) and the assistance force (Fu) taking into account the first information item (28) and the second information item (32), and an output device (44, 50) which is configured to supply at least one control signal (46, 52) to at least one component (14, 54) of the brake-power-assisted brake system taking into account the defined third information ite

Abstract: A control apparatus (12) for a brake system (10) having a housing (40) with a first (42) and second (46) cylindrical members located in first (44) and second (46) bores. The first (42) and second (46) cylindrical members and corresponding first (50) and second (54) valve seat members define first (52) and second (56) chambers within the first (44) and second (46) bores which are connected to a source of pressurized fluid. First valve means (68) are located in the first chamber (52) and second valve means (70) are located in the second chamber (56). A first plunger means (72) in the first bore (40) and a first valve seat member (50) define a first brake chamber (74) which is connected to a first set (16) of wheel brakes and a second plunger means (76) in the second bore (48) and a second valve seat member (54) define a second brake chamber (78) in the second bore (46) which is connected to a second set (16′) of wheel brakes in the vehicle.

Abstract: An arrangement for use with a valve system permits facilitated adaptation to conditions where modified lever ratios are desired while an actuation force requirement remains unaffected, or where a modified actuating force requirement is desired while lever ratios remain unchanged. In order to avoid or reduce costs associated with modification of the actuation force requirement of the valve system, a spring is provided which acts upon an operating element thereof, in addition to a pressure force, and codirectional therewith, against the actuating force in such manner that a predetermined actuating force requirement results. The invention finds particular significance in applications directed to vehicle braking systems.

Abstract: In a power-brake system, a hydraulic pressure generated by means of a pump may be supplied, controllably in proportion to an actuation force via brake conduits, by a power-brake valve to individual brake cylinders. Control pressure conduits are connected to the brake cylinders or the brake conduits in the vicinity of the brake cylinders and these control pressure conduits are connected to the brake valve. The brake pressure at the brake cylinders may be fed back, via the control pressure conduits, as the control pressure for acting on the control end of the brake valve so that a control of the control plungers of the brake valve is carried out corresponding to the brake pressure build-up at the brake cylinders and, particularly when low brake pressures are desired, rapid pressure build-up times in the brake conduits are ensured.

Abstract: A pressure medium actuated braking system comprises a first (rear axle) braking circuit, a second (front axle) braking circuit, and a multi-circuit braking power imparting device, such as a motorcar brake valve. The motorcar brake valve produces first and second control signals for the first and second braking circuits. The first braking circuit has a first pressure medium storage container assigned to it, at least one braking cylinder, and a first control valve system which connects the braking cylinder to the first pressure medium storage container or to a pressure medium sink (atmosphere) depending on the first control signal. The second braking circuit has a second pressure medium storage container, first and second braking cylinders, and a second control valve system. The second control valve system comprises first and second control valves assigned to the first and second brake cylinders respectively of the second braking circuit.

Abstract: A fluid pressure type booster device is capable of feeding an output pressure of a fluid pressure source in a controlled manner by permitting a slide member to slide so as to balance the force acting in an advancing direction by a fluid pressure of a pressure chamber in accordance with an operation of an operating member and the reaction force of a reaction chamber. The device includes an input piston slidably fitted in a housing to define the pressure chamber between the input piston and an interlocking member, a spring mounted in a compressed manner between the input piston and the interlocking member, and an on-off valve interposed between the pressure chamber and the fluid tank so as to be closed in accordance with an advancing movement of the input piston with respect to the interlocking member by an amount not less than a predetermined value.

Abstract: The present invention provides a method of and an apparatus for regulating an electrically regulated brake circuit of a multi-circuit brake mechanism with pressure medium activated brakes. To decrease the expense of such multi-circuit brake mechanism, the invention transforms the pressure, modulated by the brake actuating mechanism, to an electrical signal and regulates or co-regulates the electrically regulated brake circuit (II) by this electrical signal.

Abstract: A hydraulic brake pressure generation apparatus which is provided with a pressure increasing valve apparatus, a fluid pressure increasing apparatus and a power valve. The pressure increasing valve apparatus receives a fluid pressure in a fluid pressure chamber of a master cylinder and then generates a fluid pressure the force of which is larger by a predetermined amount than the fluid pressure in the fluid pressure chamber.

Abstract: A hydraulic brake pressure control apparatus in which a relief valve is disposed in a fluid passage communicating a fluid pressure chamber of a master cylinder with an ejection end of a fluid pump for discharging a brake fluid to a reservoir when the brake fluid pressure in the fluid passage exceeds a predetermined value and the relief valve opens. An abutting direction of a valve member of the relief valve against a valve seat is the same as a discharging direction of the brake fluid during the opening operation of the relief valve.

Abstract: A hydraulic braking system capable of reducing the brake pedal stroke is provided by adding to the basic hydraulic braking system. The adding system is able to selectively execute the reduction of brake pedal stroke and, at the same time, capable of selectively adding anti-lock function and anti-slip function by including the changeover valves or opening and closing valves to the system. An auxiliary hydraulic pressure generator having a power hydraulic pressure source and regulator is interposed in the hydraulic conduit of at least one circuit, and an outlet port of the regulator is communicated to the wheel cylinders for connecting to the hydraulic conduit of the circuit.

Abstract: In a hydraulic braking pressure control system comprising an auxiliary hydraulic pressure generator connected to a brake device for generating a hydraulic pressure depending upon a braking operation by a brake pedal; a supply source; a supply source pressure control device controlling the pressure from the supply source in accordance with the braking operation by the brake pedal; pressure transmitting device interposed in a hydraulic pressure path extending from the supply source via the supply source pressure control device to the brake device arranged to permit the transmission of the hydraulic pressure output from the supply source pressure control device to the brake device when the hydraulic pressure in the supply source is normal and to cut off the flowing of a working fluid from the brake device toward the supply source when the hydraulic pressure in the supply source is abnormally reduced; and an on-off valve interposed between the auxiliary hydraulic pressure generator and the brake device, having a

Abstract: A hydraulic braking system for an automotive vehicle having a power source for generating a hydraulic power pressure, a reservoir, a master cylinder, a hydraulic booster for actuating the master cylinder in response to depression of a brake pedal and a plurality of wheel brake cylinders for braking respective road wheels, which are divided into a first group of wheel brake cylinders communicating with the master cylinder and a second group of wheel brake cylinders communicating with the hydraulic booster. An auxiliary cylinder is disposed between the master cylinder and the first group of wheel brake cylinders to which a hydraulic braking pressure from the master cylinder is directly applied in its inoperative condition, and it increases the hydraulic braking pressure in response to depression of the brake pedal in its operative condition which is made when the hydraulic power pressure, for example, is less than the hydraulic braking pressure by a predetermined difference.

Abstract: An anti-locking automotive vehicle braking unit wherein to achieve a reduction of the costs of manufacture and of mounting with an increase of reliability in operation, a pneumatic device (39, 40) is provided for venting of the first power chamber (5) and/or evacuation of the second power chamber (6) of the vacuum brake power booster (1) in the event of a slip control action. This renders the boosting power of the vacuum brake power booster effective or ineffective in a direction opposed to the direction of actuation of the master brake cylinder (2).

Abstract: A fail safe control for a brake unit with an integral hydraulic brake booster for a road vehicle with a hydraulic dual-circuit braking system having a static front-axle brake circuit and a static rear-axle brake circuit connected respectively to primary and a secondary outlet-pressure space. The primary outlet-pressure space is delimited, by a piston element of the primary-piston arrangement and is in constant communicating connection with a second part space which is delimited by a secondary piston and by two piston elements which are displaceable relative to one another. One of these two piston elements is designed as an annular piston and the second as a plunger piston. A yoke-shaped first axial-force transmission element couples the primary piston with only one of the two piston elements.

Abstract: An off-road vehicle has ground supports on each side which can be simultaneously braked, or independently braked to aid in steering. A braking system includes a brake valve device which feeds high fluid pressure to a pair of reversing valves. The reversing valves deliver the high pressure to respective wheel brake cylinders disposed on opposite sides of the vehicle. The reversing valves and brake valve device are controlled by a common pedal which comprises separately or simultaneously actuable half-pedals. Each half-pedal actuates the brake valve device and a respective reversing valve such that when both half-pedals are depressed the system operates in a dual-sided braking mode, and when only one half-pedal is depressed the system operates in a braked-steering mode. The system can be shifted directly from the dual-sided braking mode to a brake-steering mode by simply releasing one of the half-pedals without having to first release all braking action.

Abstract: There is disclosed an apparatus for controlling brake fluid pressure of a vehicle. A supply valve of the normally closed type is opened only at the time of an anti-lock control so as to supply fluid pressure from an accumulator to a pressure fluid chamber of a master cylinder. An intake valve normally shuts off the communication between the accumulator and the fluid pressure chamber. A valve operating member for movement with a main piston of the master cylinder is engageable with a distal end of the intake valve projecting into the fluid pressure chamber to open the intake valve when the stroke of the main piston reaches a predetermined value, thereby communicating the fluid pressure chamber with the accumulator. An auxiliary piston is slidably mounted around the main piston so as to urge the main piston to move at the time of the traction control. A fluid pressure within an auxiliary fluid pressure chamber provided around the auxiliary piston acts on the auxiliary piston.

Abstract: A braking system for an aircraft towing vehicle which supports the nose wheel of an aircraft in a raised position and firmly clamps it to the vehicle. The braking force generated by the front wheels of the towing vehicle is greater by about 2:1 to 8:1 than the braking force at the rear wheels. The braking system has two hydraulic circuits employing identical braking cylinders at all four wheels of the vehicle. The number of cylinders per wheel are varied and different effective lever arms are used to generate like braking forces at each side of the vehicle, and the relatively greater braking force at the front wheels, even if one of the hydraulic circuits fails. The system limits the braking force at the front and rear wheels to maximum values to prevent excessive forces from damaging the nose gear of relatively smaller aircraft.

Abstract: A brake system having anti-skid control for motor vehicles has a brake booster having a brake valve and an emergency brake piston, and a master brake cylinder, combined in one housing with the brake booster having a master brake piston and two separate brake chambers, which supply brake fluid to one dynamic brake circuit and one static brake circuit (II and I), respectively. If the pressure fails, the master brake piston is mechanically actuated via the emergency brake piston. To attain a simple structure with a feedback-free brake pedal during anti-skid control, the emergency brake piston and the master brake piston are accommodated in a continuous housing bore such that the emergency brake piston forms the second defining wall for the first brake chamber, and the master brake piston rests with force on the emergency brake piston. A device for restoring the emergency brake piston upon the onset of the anti-skid control assure free mobility of the master brake piston.

Abstract: A hydraulic braking system for an automotive vehicle having a power source for generating a hydraulic power pressure, a reservoir, a master cylinder, a regulator and a plurality of wheel brake cylinders for braking respective road wheels, which are divided into a first group of wheel brake cylinders communicated with the master cylinder and a second group of wheel brake cylinders communicated with the regulator. The regulator has a housing defining therein a regulator chamber for introducing the hydraulic power pressure thereinto from the power source and regulating the hydraulic power pressure into a regulated hydraulic pressure in response to the hydraulic braking pressure generated in the master cylinder, and which is positioned in substantially coaxial relationship with the master cylinder and responsive mechanically to depression of a brake pedal.

Abstract: The device comprises a tandem master cylinder, a booster high pressure fluid distributor, 2, a valve mechanism 4 to interconnect the master cylinder and the distributor selectively to a braking circuit. The high pressure circuit is connected to the pipeline 46 which controls the plungers 52, 56 acting on the ball valves 50, 51 respectively. In the event of failure of the high pressure circuit,the valves 50, 51 connect the pipeline 26 directly supplied by the master cylinder and the pipeline 5 which supplies a brake motor 8 for a wheel. The device may be utilized in an anti-skid circuit.

Abstract: A system is disclosed including valves which are opened or closed dependent upon the position of master cylinder pistons. Upon commencement of slip control, pumps supply fluid either into the slip control cycle or into the working chambers depending upon the position of the pistons. As a result, the pistons are reset until a pin of the valve reaches a ramp or cam and the valve opens. When the valve is open at the start of the control, the pumps first supply fluid into the open cycle, and the pressure fluid discharged from the wheel brakes for slip control is replenished out of the pressure chambers until the pin contacts the ramp or cam whereby pressure fluid supply from the pumps takes place.

Abstract: In its simplest form, the valve comprises a body with an inlet connector and an outlet connector intended to be connected to a pressure source and a pneumatic circuit respectively. In the body, a valve comprising a seat and an obturator controls communication between the connectors. A control piston is sealingly slidably mounted in the body and, in its working travel, can cause controlled movement of the obturator away from the seat to cause controlled opening of the valve. According to the invention, the seat of the valve is formed in a member mounted in the body for movement in the direction of displacement of the obturator. A member is operatively associated with the piston and intended to cause a displacement of the seat relative to the body together with and in contact with the obturator when the control piston passes beyond a predetermined position relative to the body in its working travel.

Abstract: In a skid-controlled brake system including a diagonal division of the brake circuits (I and II), the wheel brakes (31 to 34), through main brake lines (62, 63) and branch lines (47 to 50), are in communication with the master cylinder (2) of the brake pressure generator (1), with inlet valves (24, 25 and 29, 30, respectively), open in de-energized position, being provided in the branch lines. Moreover, in-flow lines (45, 46) provided with check valves (38, 39) are couupled to the main brake lines (62, 63), through which, in the event of a locking tendency of the vehicle wheels, pressure fluid is delivered by two hydropumps (21, 26) into the brake circuits (I, II) causing the pistons (6, 7) of the master cylinder (2) to be restored against the pedal force (F) and the central control valves (10, 11) located in pistons (6, 7) to be opened thereby enabling pressure fluid to flow off into the tank (20).

Abstract: A setpont adjuster for a brake pedal in a motor vehicle to control an electric brake system. The setpoint adjuster includes a displacement sensor and a force sensor in parallel-connection, in which the force sensor supplies the reference value. Electronic main circuits are connected subsequently to the sensors and test the signals of the sensors for reasonableness according to different criteria and control a warning light in case of a fault.

Abstract: A brake pressure control unit operable by a hydraulic brake power booster and functionally corresponding to a tandem master cylinder for two statically pressurizable brake circuits has two casing bores spaced laterally apart. In one of the bores, the primary output pressure space bounded by the primary piston and floating piston is accommodated, and in the second bore, a piston which is also a floating piston, bounds the secondary output pressure space by a piston flange. The floating piston bounding the primary output pressure space on one side has the effect of building up, in the end control pressure spaces of the first and second bores, the control pressure acting on the second floating piston. This pressure leads to a displacement of the second floating piston in the sense of a pressure build-up in the secondary pressure space. The second floating piston is connected to a double-acting hydraulic cylinder, which is likewise accommodated in the second casing bore.

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: In order to apply the brake to a vehicle even if one of main air-conduits for introducing brake operating air is damaged, a brake circuit system for use in the vehicle has independent right hand and left hand main air-conduits, two front and two rear brake fluid chambers placed in the main air-conduits and connected to right and left front wheel brakes and right and left rear wheel brakes, respectively, a brake operating air reservoir divided into right and left chambers connected through the right hand and left hand air-conduits to pair of right hand front and rear brake chambers and another pair of left hand front and rear brake chambers, respectively, and two front and two rear relay valves placed in the main air-conduits, respectively. A pair of right hand front and rear relay valves and other pair of left hand front and rear relay valves are actuated to be opened and closed by the operation of right hand and left hand brake valves, respectively.

Abstract: The distributor includes a body with first and second inlet connectors for connection to two pressure sources, and first and second outlet connectors for connection to two separate brake circuits. Communication between the inlet connectors and the outlet connectors is controlled by two valves formed coaxially in the body and provided with a common control device. This device comprises first and second pistons movable coaxially in the body to control the first and second valves. The first piston is movable by means of the operation of the brake pedal and has an extension which extends through an aperture in the second. The latter has an associated spring which biasses it towards the position in which it opens the second valve. First and second reaction members are movable on the extension of the first piston, the first of these cooperating with the second piston and the second being located between the first reaction member and an end retaining head of the extension.

Abstract: A brake slip control apparatus fed with auxiliary energy for use in a vehicular hydraulic brake system, comprising a master-cylinder assembly (12) actuatable by the brake pedal, and with auxiliary energy being supplied into the working chamber (16) of the master cylinder. A resetting piston (49) is arranged axially slidably between stops on the secondary side of the master cylinder piston (23), which piston (49) causes the master cylinder piston (23) to assume a defined position in the event of application with auxiliary energy. To this end, the resetting piston (49) is slidably supported in an annular chamber (47) and, on brake actuation after having overcome a clearance (X), is entrained by the booster piston (57) in the actuating direction. Terminating into the annular chamber (49) is a throttle bore (46) through which pressure fluid out of the annular compartment (36) may enter into the annular chamber (47) in order to urge the resetting piston (49) back to its initial position.

Abstract: A brake system with hydraulic force boosting comprises a master cylinder (1) and an auxiliary pressure supply system including a hydraulic pump (10), the driving motor (M) of which is actuated when the brake is applied. The pressure in the working chambers (18,19) of the master cylinder (1) results in the re-switching of valve arrangements (2,3) with the result that the controlled auxiliary pressure is applied to the wheel brakes (4-7) in lieu of the master cylinder pressure (1). For pedal travel simulation, a hydraulic cylinder (37) is connected to a work chamber (19), with the piston (38) of the hydraulic cylinder being displaceable against a restoring spring (39) and against the controlled auxiliary pressure. A pressure-controlled multidirectional valve (40) provides for a connection of the auxiliary pressure source.

Abstract: A dual circuit brake valve is provided with a delivery differential control mechanism which controls the differential between the delivery pressures of the primary and secondary braking circuits. The delivery differential control mechanism includes a spring retainer which is mounted on the end of the stem of the relay valve and which receives a spring-biased plunger. The plunger engages with the actuating member during the brake application to thereby transfer the force of the spring to the relay member and therefore to the valve members of the secondary circuit. This transfer of the spring force reduces the crack open pressure of the valve members controlling communication through the secondary circuit, to thereby reduce the differential between the pressures generated and the primary and secondary circuits.

Abstract: A hydraulic brake booster including, master brake cylinder pistons disposed in telescoping fashion in a short housing structure, and a locking piston for the brake pedal actuation is disposed parallel to the master brake cylinder in axial alignment with the travel simulator and a brake valve. A further parallel disposition of an adjusting piston is acted upon by reservoir pressure and in which the master brake cylinder pistons are supported in a slidably displaceable manner.

Abstract: A brake system with hydraulic brake force boosting comprises a master cylinder (1), to which the wheel brakes (36 to 39, 36' to 39') are connected, as well as of an auxiliary-pressure supply system (11, 12) and of an auxiliary-pressure control valve (10) which causes an auxiliary pressure proportional to the pedal force (F). Inserted into the pressure fluid conduits from the master cylinder (1) to the wheel brakes (36 and 39, 36' to 39') are pressure-controlled multidirectional valves (15, 15', 16, 16') which, in their initial position, provide for hydraulic communication between the master cylinder (1) and the wheel brakes. After a second switch position has been assumed, the auxiliary-pressure source (11, 12) will be connected to the wheel brakes (36 to 39, 36' to 39'), whereby dynamic braking is effected instead of the master cylinder (1).

Abstract: A hydraulic brake system comprises a pedal-actuated tandem generator cylinder (3), an auxiliary-pressure supply system with electromotively driven pump (8) and pressure fluid supply reservoir (31) and an auxiliary-pressure control valve (7, 67). The tandem generator cylinder (3) is provided with a bore (24) extending wherethrough is an actuating rod (25, 72) which acts upon a primary piston (4, 68) and whose end remote from the primary piston (4, 68) cooperates with an initial-pressure piston (16) or a vacuum brake power booster (84) slidably supported in the bore (24) and being in turn coupled with the brake pedal (19) by way of a piston rod (17, 86). An annular piston (26) is displaceably arranged in the bore (24) between the primary piston (4, 68) and the initial-pressure piston (16) or, respectively, the force-output member (74) of the booster (84).

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 dual circuit brake valve includes a plunger assembly carrying the primary valve seat, and the primary valve plunger within the primary piston. A pair of axially-spaced, circumferentially extending bearing members extend from the primary piston slidably engaging larger and smaller diameter portions of the bore of the housing to thereby guide the primary piston independently of other components within the housing. The secondary set of valve actuating members is actuated by a relay piston which is similarly guided in larger and smaller diameters of the bore independently of other components within the valve housing. The primary piston defines a pressure effective area due to the difference in the larger and smaller portions, so that inlet port pressure acting on the effective area yieldably urges the plunger toward the brake released position.

Abstract: A hydraulic brake system with slip control for automotive vehicles comprising a master cylinder (2) pressurizable by a hydraulic power booster (1), in which system valve(s) (31,27,32,28,33,23) are inserted between the master cylinder (2) and the wheel brakes (29,30,24,25) connected to the master cylinder (2) which allow pressure fluid removal from the wheel brakes (29,30,24,25) that can be replenished out of the pressure chamber (19) of the hydraulic power booster (1) by way of a change-over valve (36). A stroke limitation of the brake pedal (8) is effected during slip control. The end surface of the master cylinder piston (5) close to the working chamber (16) being larger than the is effective surface of the booster piston (4), and wherein a stepped piston is employed as master cylinder piston (5) with an annular surface (18) thereof being adapted to be acted upon in the actuating direction by the pressure prevailing in the working chamber (16).

Abstract: A dual circuit foot valve for a compressed air braking system has a plunger (38) which acts through a spring (39) on a first piston (6) which carries an exhaust seat for a first double valve controlling the supply of pressure from an input port (27) to a first circuit delivery port (28), the delivered pressure at (28) acting beneath the piston (6) in a sense to cause lapping of the valve and also acting above a second piston (16) which similarly acts as a control piston for a further double valve controlling the supply of pressure from an input port (29) to a second circuit delivery port (30), a further spring 43 being carried within the piston 6 to be engageable with a projection (55) of the second piston (16) following operation of the plunger to act on the second piston to beneficially influence the differential between the two delivered pressures.

Abstract: A relay valve device having a first control surface and a second control surface. A shut-off device is located in the line feeding the control pressure into the second control surface throughout the period in which a signal pressure is present, and connecting the second control surface to atmosphere at other times. Thus, the relay valve device releases a greater pressure into a load circuit when actuated during effectiveness of the signal pressure than while the signal pressure is not effective. The shut-off device having a pressure relief valve with a switch-off device so that when the signal pressure is effective, the switch-off device switches OFF the pressure relief function of the pressure relief valve and so that when the signal pressure is not effective, the pressure relief valve is opened as long as the control pressure remains below the relief pressure and is closed when the control pressure moves above the relief pressure.

Abstract: A power brake booster including booster pressure acting upon a booster piston and controlled by a brake valve which is actuated by an actuating element supported in the booster housing is disclosed. A travel simulator is interposed between the actuating element and the brake valve. Acting on which travel simulator is a simulator piston which is acted on by the actuating pressure in opposition to main actuating direction. The simulator piston is connected to a valve spool for the purpose of actuating the brake valve. The actuating element includes a plunger piston which projects into a booster chamber and which transmits a reaction force onto the actuating element on actuation of the power brake booster.

Abstract: A tractor-trailer braking system with a control valve for the trailer which is controllable by at least two service brake circuits of the tractor. One circuit of this multi-circuit control has an electrical control in the form of magnetic valves, or the like, in order to speed up the control process. The system may be combined with a load-dependent switching element and/or with an anti-skid protection-dependent switching element.

Abstract: A dual brake valve assembly including two co-axial primary and secondary valves for primary and secondary braking circuits is modified to include an auxiliary exhaust valve operable in conjunction with the pressure plate and a secondary piston for controlling operation of the secondary valve in response to operation of the primary valve. When the valve assembly is operated to apply the brakes, the auxiliary exhaust valve remains closed to prevent the premature release of fluid from the primary circuit irrespective of uncontrolled relative movement between parts of the valve assembly.

Abstract: A pressure-medium brake system, which comprises multiple circuits and has associated with each brake cylinder or group of brake cylinders relay valves which are controllable by a control medium. Depending on the number of brake circuits and the kind of the respective control medium, the relay valves are provided with several, possibly different, control chambers. This results in an overlapping control which insures that each relay valve can even be controlled in the event that a control circuit has been lost. The brake system is preferably used in utility vehicles equipped with air brakes.

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 control system in which the master cylinder has two pressurizing chambers for each brake circuit. Three brake circuits are disclosed in detail. One piston of each set of pressurizing chambers is directly applied by brake pedal force. The other piston of each set receives brake pedal force through resilient means, with additional force supplied by suitable servomotors. The servomotors are individually controlled to provide power-assist when appropriate, or to decrease the forces supplied by them to control wheel slip or wheel spin.