Abstract: An improved force transfer arrangement for use in a dual circuit master cylinder having a pair of nested concentric pistons for pressurizing a pair of respective fluid chambers, wherein the force transfer arrangement imparts an input force from an input piston on a pair of pistons such that the pair of pistons can move relative to each other to compensate for different travel lengths. The invention discloses three embodiments of the improved force transfer arrangement. A first embodiment includes a hydraulic fluid chamber in fluid communication with the input piston and the pair of pistons. A second embodiment includes a circumferentially arranged ball mechanism positioned between the input piston and the pair of pistons. A third embodiment includes a notched lever ring assembly positioned between the input piston and the pair of pistons.

Abstract: A hydraulic pressure amplifier, coupled to a turbine, for creating a fluid impulse directed to a blade of the turbine causing it to rotate. The hydraulic pressure amplifier is comprised of a series of connected sections with each section having a large cylinder and a small cylinder with a large piston and a small piston placed therein. The small piston providing an amplified force applied to the larger surface area of the larger piston through hydraulic coupling to effectively amplify an initial pressure or force. As a result very high forces are generated with relatively small movement. A free piston placed in an impulse cylinder in an end section is struck, causing a fluid impulse. The fluid impulse creates an impulse wave used to move a blade of a turbine, causing a shaft to rotate. An efficient rotational motor is achieved that has many practical applications. Additionally, the hydraulic pressure amplifier may be used in any application where a very high force is desired with relatively little motion.

Abstract: A vehicle brake booster comprises: a body having an input port, an output port, and a flow path through which the input port is communicated with the output port; a first piston which is arranged in the flow path, and on which the hydraulic pressure in the flow path acts; a control valve which is abutted against the first piston, and defines a control chamber which is able to introduce or block the hydraulic pressure of an accumulator; a second piston which is arranged downstream of the first piston in the flow path, the second piston being in the form of a stepped piston having a large diameter portion and a small-diameter portion to the end of which the hydraulic pressure in the flow path is applied, and being able to produce a wheel cylinder pressure; a hydraulic pressure chamber formed in the large-diameter portion of the second piston; and a cut valve arranged downstream of the second piston in the flow path.

Abstract: A hydraulic oil well pump drive system for driving an oil well sucker rod includes a master piston positioned within a master cylinder for axial displacement between first and second ends of the master cylinder. The master piston has a piston drive rod which extends through one end of the master cylinder. The drive rod is connected to a crank pin of an eccentric crank. A center seal assembly divides the master cylinder into a working chamber and a pressure chamber in opposite ends of the master cylinder. Each respective chamber defines a fluid volume which varies with the displacement of the master piston. The master piston displacement creates a bi-directional flow of working fluid from the working chamber. A wellhead hydraulic assembly is operably connected to the oil well sucker rod and is in fluid communication with the master cylinder working chamber to receive the working fluid flow.

Abstract: A two-stage brake valve includes a valve housing. The valve housing contains a chamber, one side of which serves as an equalizing reservoir which is connected directly or indirectly with at least one brake cylinder bore which is formed in the valve housing. The other side of the chamber forms an emergency steering volume for a hydrostatic steering circuit. A return line of the hydrostatic steering circuit opens into the chamber and an overflow opening communicates an upper region of the chamber through a channel to a fluid reservoir. To prevent foaming brake fluid from reaching the brake circuit, an intermediate wall separates the equalizing reservoir from the emergency steering volume. The equalizing reservoir and the emergency steering volume are connected to each other via an equalizing opening.

Abstract: A two stage brake valve communicates fluid pressure to a brake mechanism. The brake valve has an inlet for receiving pressurized brake fluid from a pump, a reservoir port, a stepped bore and a stepped piston member comprising a larger diameter prefill piston and a smaller diameter high pressure piston. The stepped bore and the stepped piston form a high volume prefill chamber and a high pressure chamber. The high pressure piston has a metering groove which controls communication between the inlet and the brake mechanism. A bleed orifice is formed in the high pressure piston and communicates the high pressure chamber to an outer surface of the high pressure piston. The bleed orifice includes an annular bleed groove formed in an outer surface of the high pressure piston and a radial passage extending from the bleed groove to an interior of the high pressure piston.

Abstract: A brake-pressure modulation device in which a hydraulic unit, fitted with solenoid valves, with return pumps, accumulators and dampers of an anti-lock brake system also has a tandem brake master cylinder. The hydraulic unit has a housing with a standard location hole, into which four lip seals identical at least in their outside diameters are inserted. The lip seals hold a primary and a secondary piston of the tandem brake master cylinder. The use of four lip seals with the same outside diameter makes it possible to use the same housing with the standard location hole for different types of vehicle, even when the piston diameter and the operating stroke are changed.

Abstract: A two-stage pressure cylinder having a work cylinder (17,100) with a work piston (18,108), and piston rod (20,110) for contact with a work piece, in which the work piston is movable, an oil cylinder (56,116) to contain hydraulic fluid (H), an oil piston (58,118) in the oil cylinder, an air cylinder (72,122), an air piston (74,124) in the air cylinder, and an air piston rod (80,126) connected to the air piston and communicating with the hydraulic fluid, and valves allowing hydraulic fluid to pass from the oil cylinder to the work cylinder to operate the work piston, and on a reverse stroke flow being operable to permit return flow of fluid from the work cylinder into the oil cylinder.

Abstract: A hydraulic oil well pump drive system for driving an oil well sucker rod includes a master piston positioned within a master cylinder for axial displacement between first and second ends of the master cylinder. The master piston has a piston drive rod which extends through one end of the master cylinder. The drive rod is connected to a crank pin of an eccentric crank. A center seal assembly divides the master cylinder into a working chamber and a pressure chamber in opposite ends of the master cylinder. Each respective chamber defines a fluid volume which varies with the displacement of the master piston. The master piston displacement creates a bi-directional flow of working fluid from the working chamber. A wellhead hydraulic assembly is operably connected to the oil well sucker rod and is in fluid communication with the master cylinder working chamber to receive the working fluid flow.

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 closed loop fully self-contained actuation system for converting a mechanical input motion into a mechanical output motion, which actuates a device such as a flight control surface on an aircraft, comprises an input actuator including a first fluid pressurizing means responsive to the mechanical input motion, and an output actuator including a second fluid pressurizing means, as well as a flexible fluid line extending between the first and second fluid pressurizing means to provide fluid communication therebetween. The second fluid pressurizing means is responsive to fluid flow through the fluid line, thereby initialing the output motion. The system is advantageous because it requires no hydraulic pumps, no accumulators, no reservoirs, and no dynamic seals or mechanical joints, permitting great reliability. The actuation system may be easily folded in conjunction with the apparatus on which it is employed, for compact storage.

Abstract: Tandem master cylinder comprises primary and secondary pistons (3,4) moved apart by means of two springs (9, 10). Only one (9) of the two springs is prestressed in the rest position of the piston. The pressures in the primary 6 and secondary 7 chambers are thus very rapidly made similar to each other, without it being necessary to mount the springs in a cage of adjustable length.

Abstract: A method for preventing bedsores is disclosed which includes rocking the patient slowly at a rocking cycle period in the range of 1 to 120 minutes. Preferably, the entire bed is rocked using a hydraulic system characterized by synchronous motion of the master cylinders and the slave cylinders at the desired rocking cycle period. A pump is disclosed characterized by 4 master cylinders for conducting the rocking. The system constitutes an attachment for a bed such as hospital bed.

Abstract: Left and right two stage brake valves communicate fluid pressure to left and right brake mechanisms, each brake valve having an inlet for receiving pressurized brake fluid, a reservoir, a stepped bore and a stepped piston. The stepped bore and the stepped piston forming a high volume prefill chamber and a high pressure chamber. A prefill drain valve communicates the prefill chambers to the reservoir only when pump pressure is available at the inlet and blocks communication between the left and right prefill chambers and between the prefill chambers and a reservoir when pump pressure is not available at the inlet.

Abstract: A hydraulic pressure control apparatus comprising: an introducing valve provided on a supply duct connecting to each other a hydraulic source and a control chamber for controlling a fluid-operated equipment or increasing or decreasing the hydraulic pressure of the fluid-operated equipment; and a discharge valve provided on a discharge duct discharging hydraulic fluid from the fluid-operated equipment or the control chamber. The introducing valve and/or the discharge valve are disposed in series on the supply duct or the discharge duct; at least one of a plurality of the introducing valves and/or the discharge valves consists of a flow rate-variable valve capable of changing the flow rate of the hydraulic fluid continuously according to the intensity of electric current; and the other introducing valves and/or discharge valves consist of electromagnetic change-over valves fully opened or fully closed.

Abstract: A master cylinder having first and second compensating ports with a plurality of openings therein for rapidly allowing fluid communication between a reservoir and first and second chambers to maintain the master cylinder in a ready condition with respect to an input force in the development of pressurized fluid to effect a brake application.

Abstract: An arrangement for a master cylinder and a vacuum booster for an automotive vehicle is provided including a vacuum booster having a first travel axis generally parallel with a travel axis of a vehicle and a housing for attachment to the vehicle, a master cylinder for fluidly actuating a braking system, the master cylinder having a piston slidably mounted along a second travel axis generally perpendicular to the first travel axis, a tubular enclosed conduit relay housing having a first end connected with the booster housing having a first opening and a second opening, the relay housing being connected with and supporting the master cylinder housing at a position spaced away from the vacuum booster housing, and a relay link pivotally mounted with respect to the relay housing by the pin, the relay link transmitting force between the booster and the master cylinder via first and second pivotally connected clevises.

Abstract: A closed loop fully self-contained actuation system for converting a mechanical input motion into a mechanical output motion, which actuates a device such as a flight control surface on an aircraft, comprises an input actuator including a first fluid pressurizing means responsive to the mechanical input motion, and an output actuator including a second fluid pressurizing means, as well as a flexible fluid line extending between the first and second fluid pressurizing means to provide fluid communication therebetween. The second fluid pressurizing means is responsive to fluid flow through the fluid line, thereby initialing the output motion. The system is advantageous because it requires no hydraulic pumps, no accumulators, no reservoirs, and no dynamic seals or mechanical joints, permitting great reliability. The actuation system may be easily folded in conjunction with the apparatus on which it is employed, for compact storage.

Abstract: A hydraulic pressure actuating system has a master cylinder pivotally mounted to the dash panel in line with the actuator pedal, a remotely mounted hydraulic fluid reservoir assembly positioned at the high point of the system for selfbleeding, and an actuating device actuated by pressurized fluid generated by actuation of the master cylinder. The reservoir assembly uses a fluid flow valve mechanism to control its connection with the fluid passage of the system. Several types of reservoirs are disclosed, including a siphon tube arrangement and various flexible bag arrangements. The reservoir volume is contained in minimum space by using a sidesaddle reservoir arrangement. Indicator arrangements are also disclosed which when actuated indicate actuation and release of the master cylinder in one instance and the amount of fluid in a flexible bag reservoir in another instance.

Abstract: The subject invention relates to a fluid pressure intensifier (32) for increasing the pressure of an incompressible fluid and comprises a fluid reservoir (112) supplying fluid to a cylinder housing (72). The housing (72) includes first inlet (88) and outlet (90) cylinders extending between opposite ends (74,76) of the housing (72) and slideably receiving first inlet (96) and outlet (100) pistons therein. Second inlet (92) and outlet (94) cylinders are spaced parallel to the first cylinders (88,90) and further extend between the housing ends (74,76) for slideably receiving second inlet (98) and outlet (102) pistons therein. The first pistons (96,100) are forced in unison axially through the housing (72) to increase the pressure of the hydraulic fluid in the first outlet cylinder (90).

Abstract: A two-stage brake control valve has a larger first stage and a smaller second stage. First stage operates to fill a brake. Then, after a transition phase only the second stage is used to supply the working pressure. A check valve is between the first stage pressure chamber a sump. The check valve opens if the pressure in the first stage pressure chamber exceeds a predetermined value. To minimize the operating force of the valve and to avoid a sudden change of the valve working pressure during the changing phase, the closing force of the check valve is controlled as a function of the valve working pressure. The valve working pressure acts on a valve spool which influences the closing force of the check valve in the way that the closing force decreases with increasing working pressure.

Abstract: A two-stage brake valve includes a stepped valve bore and pressure piston defining a first stage with a large effective area and a second stage with a smaller effective area. The two stages become effective in succession so that, initially the first stage is used to fill a system and then, following a transitional phase, the second stage generates an operating pressure. A relief channel communicates the pressure chamber of the first stage with a reservoir. A relief valve closes the relief channel in response to an excess pressure generated by operation of the second stage.

Abstract: A pressure intensifier drive unit has walls that form a cylinder with an intermediate divider plug separating a working chamber and a pressure intensifying chamber aligned in the cylinder. The working chamber has a working piston and a working piston rod extending from an end of the cylinder. A carrier piston is located between the working piston and the divider plug and has a cylindrical recess receiving the working piston, a hydraulic fluid chamber, and a bore. A locking piston is movably mounted on the carrier piston and locks the carrier piston in place when the working piston rod initially contacts a workpiece. A pressure intensifier piston in the pressure intensifying chamber has a pressure intensifier piston rod extending through a bore in the divider plug and through the bore in the carrier piston into the hydraulic fluid chamber.

Abstract: A modular digital actuator is formed by interconnecting a plurality of modules. Each of the modules includes a housing having a pair of different sized axially extending cylinder sections in which is received a T-shaped piston with the top of the T mating with the larger cylinder and the leg of the T forming a piston in the smaller cylinder. The leg of the T is hollow and forms a cylinder to receive an axially extending piston forming shaft to thereby provide three preferably different sized cooperating piston and cylinder areas, one formed in the cavity or hollows of the leg of the T, a second formed between the top of the T surrounding the leg of the T and the junction between the larger cylinder section and smaller cylinder section and the third formed in the smaller cylinder section between a closed free end of the smaller cylinder section and the leg of the T surrounding the piston forming shaft. The top of the T forms a piston wall in a fourth hydraulic cavity.

Abstract: In order to reduce the number of component parts required for a master cylinder incorporated in a hydraulic brake system and steering brake system which is composed of two master cylinders interconnected through a compensating line, it is suggested by the present invention that the compensating line (60) be connected to a compensating chamber (22) adjacent to the pressure chamber (21), and that a valve assembly isolating the pressure chamber (21) from the compensating chamber (22) be formed by a sealing cup (7) arranged on an operating piston (3) that is actuatable by the master cylinder piston (2).

Abstract: The boosted brake system comprises two tandem master cylinders (15, 16), each controlled by way of the piston of a vacuum booster (10, 11) comprising at least two chambers, one (10) of these brake boosters being controlled by way of a pedal and comprising a valve mechanism making it possible to generate a difference between the pressures prevailing in the two corresponding chambers, and a reservoir (17) for feeding brake fluid to the associated hydraulic circuits the two chambers of one (10) of these boosters communicate respectively with the two corresponding chambers of the other booster (11), and the two hydraulic circuits (30, 32) associated with one (15) of the master cylinders communicate respectively with the two hydraulic circuits (30, 32) of the other master cylinder (16).

Abstract: A vacuum brake power booster is presented in which the vacuum control valve (81) is arranged parallel to the master cylinder (55). The housing (92) of the booster is used as a carrier element for actuating members, such as the brake pedal (60, 8) and the clutch pedal (11) as well as for other elements. A twin master cylinder is employed. A short overall axial length and a space-saving design of the assembly as a whole, enabling efficient incorporation of the overall assembly at the assembly line of the vehicle manufacturer, are achieved by the selection and arrangement of the components of the brake power booster and of the master cylinder, as well as of the actuating members.

Abstract: The present invention provides a pneumatically powered actuator having hydraulic control for both locking and controlling the velocity of an output rod without any sponginess. The invention includes a double-acting pneumatic actuator having a bore, a piston slidably engaged within the bore, and a control rod connected to the piston. The double-acting pneumatic actuator is mounted to a frame. A first double-acting hydraulic actuator having a bore, a piston slidably engaged within the bore, and a follower rod mounted to the piston is mounted to the frame such that the follower rod is fixedly connected to the control rod. The maximum translation of the piston within the bore of the first double-acting hydraulic actuator provides a volumetric displacement V.sub.1. The present invention also includes a second double-acting hydraulic actuator having a bore, a piston slidably engaged within the bore, and an output rod mounted to the piston.

Abstract: A hydraulic booster for a vehicle brake master cylinder having a power piston with only one large diameter sliding seal which is exposed to a high hydraulic pressure. This provides a brake booster having lower hysteresis.

Abstract: In a veneer stacking system, a sensing device for sensing the incoming veneer sheets and computer determining from the information of the sensing device the stack on which the sheets are to be deposited. Knock-off shoes are positioned above the path of incoming veneer sheets. Multiple hydraulic cylinders connected into a hydraulic control system controls movement of the shoes. The multiple cylinders are simultaneously actuated by master cylinders which in turn are simultaneously actuated by a computer controlled mover piston. Air leaked into the hydraulic system is bled off by bleed orifices in the master cylinders communicating with a hydraulic fluid reservoir whereby air rises in the system up through the orifices and into the reservoir.

Abstract: A fluid circuit assembly for maintaining substantially constant pressure between two abutting solid objects, the circuit assembly comprising a master cylinder assembly, a plurality of working cylinder assemblies, piston rods extending from the working cylinder assemblies, a spool on distal ends of the piston rods adapted to engage a surface against which it is desired to maintain constant pressure, the master cylinder and the working cylinders having first chambers in communication with a first fluid circuit, the master cylinder having a second chamber in communication with a source of gas under a selected substantially constant pressure, said gas being in communication with a gas reservoir portion of a liquid/gas tank, a liquid reservoir portion of said tank being in communication with second chambers of said working cylinder assemblies, such that upon change of pressure on the spool by the surface, a reaction is generated in the circuit assembly, such as to move the spool to restore a selected pressure betw

Abstract: In a hydraulic cylinder apparatus of a type actuated by a booster, a plunger chamber (39) of a booster (32) is connected in communication with an extension cylinder chamber (35) of a hydraulic cylinder (30). An annular oil make-up chamber (48) is disposed outside an outer peripheral surface of the cylinder chamber (35). The oil make-up chamber (48) is connected in communication with the plunger chamber (39) and an electromagnetically opened and closed type shutoff valve (49) is interposed between both said chambers (39) (48).

Abstract: A twin master cylinder for a road vehicle brake system has master cylinders assigned respectively, to a front-axle brake circuit and to a rear-axle brake circuit. The master cylinders are arranged laterally next to one another in a common housing and are each actuable via an arm of a pivotable rocker with a variable ratio L1/L2 of the lengths L1 and L2 of arms of the rocker. A supporting element is provided which, by its support point on the pivotable rocker, marks the pivot axis of the rocker and, by support on a push-rod piece, transmits the actuating force acting on piece to the rocker. The supporting element is arranged between the rocker and the supporting surface of the push-rod so as to be displaceable transversely relative to the direction of exertion of the actuating force.

Abstract: In a brake apparatus for a hydraulic two-circuit brake installation of a road vehicle with static brake circuits, an outlet pressure space is provided for one of these brake circuits in which the brake pressure that is coupled into a static brake circuit of the vehicle, is adapted to be built up by the displacement in the same direction of a master cylinder piston which is also displaceable by the pedal force alone, and of a servo piston which is displaceable only when the brake force servo unit is intact.

Abstract: This invention comprises four hydraulic muscle pumps connected to four hydraulic dynamic muscles in hermetically sealed pairs to transfer tensive forces from a local to a remote location for use in actuating the articulation section of a borescope or endoscope.

Abstract: A brake pressure generator for brake systems exhibiting an anti-locking control comprises a vacuum brake force booster (1), and a master brake cylinder (2) coupled upstream thereto, a vacuum counter-force generator (6 or 6') and a hydraulic force converter (27). The pressure and the pressure difference, respectively, in chambers (15 or 15'; 16 or 16') of the counter-force generator (6 or 6') are controlled with the aid of electrically reswitchable multi-way valves (17 to 17') in communication with the atmosphere (Atm) and the vacuum (Vac) source.

Abstract: A brake control valve has a valve bore, a piston member and an end member closing one end of the valve bore. One of the piston and end members has a projection and the other member has a corresponding blind bore for sealingly receiving the projection. The blind bore and the projection are spaced apart axially in the rest position of the piston. Upon axial movement of the piston the projection is sealingly received by the blind bore so that the effective working area of piston is reduced. By means of appropriate channels and grooves the chamber surrounding the projection is connected to reservoir.

Abstract: The invention relates to an assisted hydraulic braking system comprising a brake pedal (10) connected to an actuating rod (46), a pneumatic brake booster (14) comprising a front vacuum chamber (102) and a rear working chamber (104) separated by a movable deformable partition acting on a push rod, a single master cylinder (16) the piston of which is acted by the push rod, a mechanism (12) for controlling the booster (14), comprising a shutter mechanism (34) putting a first chamber (26) selectively in communication with a second chamber (30) or with the atmosphere responsive to an actuating of the brake pedal (10), a first pipeline (110) putting the first chamber (26) of the control mechanism (12) in communication with the working chamber (104) of the booster (14), a second pipeline (112) putting the second chamber (30) of the control mechanism (12) in communication with the vacuum chamber (102) of the booster (14), a second master cylinder (74) the outlets of which are connected to at least one wheel brake, th

Abstract: A master cylinder assembly wherein pressure cylinders are formed in a body and interconnected by a transfer passage through which fluid flow is controlled by valve elements. The valve elements are operated in response to actuating pressure in the cylinders and are opened by this pressure to interconnect the cylinders when the latter are pressurized simultaneously. When only one cylinder is pressurized, the valve elements associated with other cylinders remain closed to prevent fluid flow through the transfer passage. The valve elements have stems which control expulsion of fluid from the cylinders through outlets.

Abstract: A brake unit having a hydraulic brake booster and twin master cylinders in a common housing. The brake booster comprises a drive cylinder between the master cylinders which can be subjected to the outlet pressure of a brake valve of the brake booster which supplies an outlet pressure proportional to the pedal travel. A compensating cylinder, which jointly executes the strokes of the drive-cylinder piston and can likewise be subjected to the outlet pressure of the brake valve transmits the actuating forces generated by the drive cylinder to the pistons of the master cylinders via a rocker articulated pivotably on the compensating piston. The effective piston surface of the compensating cylinder is somewhat larger than that of the drive piston.

Abstract: An electro-hydraulic actuator assembly comprises a master piston-and-cylinder 32, 42 connected to be driven by a rotary actuator 56 and hydraulically connected to a slave master piston-and-cylinder 12 coupled to an output member, e.g. a throttle linkage rod 10, for automatic control of the displacement of the member 10. An override for manual control of the member 10 is provided by a valve 60 which, when opened, hydraulically shortcircuits the member 10 by equalizing pressures on the two sides of the slave piston 16. To re-establish automatic control and synchronize master and slave, a (possibly remote) controller 80 shuts the valve 60 and drives the actuator 56 until master and slave pistons both attain end positions; if necessary, by reopening valve 60 for a short time and continuing to drive the actuator 56.

Abstract: An adaptive braking system (10, 210) for an automotive vehicle provides a three-channel split pump-back system which may be utilized with either two- or three-chamber master cylinders. The three-channel adaptive braking system (10, 210) includes a first braking circuit (40) for controlling one of the front wheel brakes (25), a second braking circuit (60) for controlling the other of the front wheel brakes (27), and a third braking circuit (80) for controlling the rear wheel brakes (24). A two-section pump (110) provides hydraulic pressure for the first and second braking circuits (40, 60) and for the third braking circuit (80). Alternatively, a three-section pump (310) can provide hydraulic pressure for each of the circuits (40, 60, 80).

Abstract: A mechanical arrangement to provide power assistance for the application of vehicle brakes with a positive shut-off of power assistance immediately upon release of the brake control by the user. The shut-off is achieved mechanically by providing pressure relief from the power assist pressure chamber by connecting a pressure relief channel between the power assist chamber and the brake fluid reservoir or by disconnecting the power piston in the power assist chamber from the main piston as soon as the brake control is released by the user.

Abstract: A vehicle brake system comprises two pressure modulators (16, 18) one of which (16) is associated with one of the brake circuits (12) and the other of which (18) is associated with the other (14) of the brake circuits. The modulators (16, 18) are accommodated in a housing, preferably in the form of a twin arrangement, and are actuated by means of a common drive unit. The pressure modulators (16, 18) each include a plunger piston (78) which is acted on by a differential gear in the common drive unit. In a first embodiment, a vacuum servo drive (20) serves as the drive unit and the differential gear comprises a linear guiding element (106) and an angular lever (112) articulated thereto. The force required to hold down the plunger pistons (78) in their initial position can be applied mainly pneumatically. A ventilatable chamber (M2) of the vacuum servo drive (20) being connected for that purpose with the ventilatable working chamber (B2) of a vacuum brake power booster (32 ).

Abstract: A brake booster has a first booster cylinder and a booster piston disposed in it for displacing a master cylinder piston to pressurize a brake circuit. A tappet displaces the first booster piston directly if boost fluid pressure is inadequate. A second booster piston in a parallel booster cylinder drives a pump piston which also pressurizes the brake circuit. The second booster piston and the pump piston have hydraulically effective surface areas which are matched to one another so as to have a larger boosting ratio than the first booster piston and master cylinder piston. Forward displacement of the second booster piston causes a bent arm to contact and push the first booster piston forward. If the boost pressure supply apparatus fails, then only the first booster piston and the master cylinder piston are displaced by the brake pedal; brake pedal travel increases considerably.

Abstract: A fluid actuator including at least two cylinders connected to a common pressurized-fluid supply mechanism. Actuation units are connected to piston rods of the cylinders, respectively. The piston of one of the cylinders is operated by pressurized fluid, and when the piston is moved back, the pressure in the cylinder is increased to operate the piston of the other cylinder. The actuation units are thus operated with a certain amount of interval of time or in a synchronous mode.

Abstract: This brake system contains a braking pressure generator aggregate which influences the rear axle braking pressure so as to control the braking force distribution between front and rear axles in dependence on the static and dynamic axle load distribution and on other parameters resulting from the braking behavior. The braking pressure generator aggregate is connected to a tandem master brake cylinder and pressurized by an operating pressure, the braking pressure generator aggregate reduces in a ratio corresponding to a basic rating of the braking force distribution and makes available for basic rear axle braking pressure. The tandem master brake cylinder thus performs the major part of the braking operation at the rear axle. A vacuum servo drive is a part of the braking pressure generator aggregate and is activated in order to raise or lower the braking pressure at the rear axle above or below the basic braking pressure.

Abstract: A brake system with anti-skid control and/or traction slip control is disclosed. This system includes a pedal-operated braking pressure generator and an auxiliary-force-generating system connected between the brake pedal and the braking pressure generator for generating auxiliary forces for assisting the pedal force or for generating an opposed force dependent on the brake pedal travel, the rotational behavior of the wheels and on predetermined control patterns. Control elements in the form of electric linear motors or hydraulically or vacuum-driven servomotors are used for generating the auxiliary forces.

Abstract: A brake system for automotive vehicles is disclosed comprising a vacuum brake force booster operatively located between a brake pedal and a master brake cylinder. The vacuum brake force booster includes at least two working chambers separated from one another by a membrane plate, one of the working chambers, through a master magnetic valve, being in communication with a vacuum source and the other working chamber being vented through a control valve acutable by the brake pedal to generate a brake force proportional to the brake pedal force. Connected to the master brake cylinder are brake circuits applying pressure to the wheel brake cylinders. Sensors associated with the wheels detect the rotational behavior of the wheels to identify a locking condition.

Abstract: An integrated anti-lock braking system includes a master cylinder, a modulator valve assembly, an electric motor pump, a brake proportioning valve, and a differential pressure valve all integrated into a common assembly. Primary and secondary fluid passages defined within the housing are provided to communicate the various devices included within the assembly. The assembly includes a bracket engaging portion upon which a mounting bracket is provided to attach the assembly to the vehicle and which is capable of mounting the assembly to accommodate mounting at selected angles.