Abstract: A hydraulic brake system with slip control for automotive vehicles, comprises a master cylinder (2) pressurizable by a hydraulic power booster (1), in which system valve members (39, 40, 43, 44, 47) are inserted between the master cylinder (2) and the wheel brakes (45, 46, 41, 42) connected thereto which serve to remove pressure fluid from the wheel brakes (41, 42, 45, 46). Pressure fluid taken from the wheel brakes (41, 42, 45, 46) is replenished out of the pressure chamber (6) of the hydraulic power booster (1). A stroke limitation of the brake pedal (7) is effected during slip control.

Abstract: A brake pressure generator for an automotive hydraulic brake system, wherein a booster piston (13) which is displaceable by an auxiliary hydraulic pressure in the direction of actuation is adapted to mechanically strike an annular piston (18) and is displaceable in the actuating direction. Sealingly guided within the annular piston (18) is a master cylinder piston (25) confining at least one working chamber (23) separable from an unpressurized supply reservoir (32), by a valve (31) controllable in way-responsive manner. Annular piston (18) is of a stepped-piston configuration and is provided with a section (19) facing pedal actuation (6) and being of a smaller diameter. According to the invention it is suggested that the pedal-sided section (19) of annular piston (18) is of a smaller diameter than that of the booster piston (13) to confine an annular chamber (22) which via a check valve (33) adapted to be switched open toward working chamber (23), is in communication with working chamber (23).

Abstract: A hydraulic brake system with slip control, in particular for automotive vehicles, comprising a master cylinder (2) actuatable by a hydraulic power booster (1), in which brake system valve means (23, 24, 28, 29, 32, 33, 34, 35) are inserted between the master cylinder (2) and the wheel brakes (25, 26, 30, 31), connected to the master cylinder (2) which allow to remove pressure fluid from the wheel brakes (25, 26, 30, 31), while the pressure fluid taken from the wheel brakes (25, 26, 30, 31) can be replenished out of the pressure chamber (10) of the hydraulic power booster (1), wherein the master cylinder piston (5) is designed as a stepped piston and an annular surface (18) of the master cylinder piston (5) remote from the working chamber (16) is adapted to be acted upon by the pressure of the working chamber (16), and wherein the chamber (19) confined by the annular surface (18) is connectible to an unpressurized supply reservoir (11) by way of a travel-responsively controllable valve (51).

Abstract: In the assembly of a master cylinder and an oil-hydraulic booster connected to the rear thereof, the master cylinder has an axial bore consisting of a forward, small-diameter bore section and a rearward, large-diameter bore section and the master cylinder piston in the master cylinder includes a small-diameter section slidably fitted in the small-diameter bore section of the master cylinder and a large-diameter section slidably fitted in the large-diameter bore section thereof. The forward end portion of the piston in the oil-hydraulic booster is formed smaller in diameter than the large-diameter bore section of the maste cylinder and is arranged proximate the large-diameter section of the master cylinder piston in the master cylinder so as to enter the large-diameter bore section of the master cylinder when the booster piston is advanced.

Abstract: Various buoyant valve arrangements are utilized to prevent quick take-up pressure from entering the master cylinder reservoir chamber until the quick take-up pressure reaches the desired value. A resiliently biased check valve is provided which opens at a predetermined quick take-up pressure to limit the amount of quick take-up pressure generated and then vents excess brake fluid from the quick take-up chamber into the reservoir chamber. The check valve may be resiliently biased by a spring or by elastic tension in an O-ring valve member.

Abstract: Various buoyant valve arrangements are utilized to prevent quick take-up pressure from entering the master cylinder reservoir chamber until the quick take-up pressure reaches the desired value. A resiliently biased check valve is provided which opens at a predetermined quick take-up pressure to limit the amount of quick take-up pressure generated and then vents excess brake fluid from the quick take-up chamber into the reservoir chamber. The check valve may be resiliently biased by a spring or by elastic tension in an O-ring valve member.

Abstract: In a tandem master cylinder for a vehicle hydraulic brake system having a push-rod piston designed as stepped piston and an intermediate piston designed as stepped piston both pistons being aligned in a stepped bore of the cylinder housing for the purpose of obtaining a particularly short and compact design. The working cylinder communicates with the connecting bore of the one brake circuit provided in the large-diameter step of the intermediate piston, while the small-diameter step of the intermediate piston fits in the working cylinder formed by the small-diameter step of the stepped bore so that the working cylinder is in communication with the other brake circuit via the connecting bore.

Abstract: A master cylinder construction for automotive brake systems incorporating a servo mechanism in which the master cylinder consists of primary, secondary and fast fill pistons arranged in tandem, the fast fill piston operating in a bore of a larger diameter than that of the primary and secondary pistons the arrangement being characterized in that the fast fill piston is of hollow annular construction consisting of an inner cylindrical wall and an outer cylindrical wall joined together at one end and defining between them an annular space open at the other end, the outer wall being arranged to stroke past a seal into an annular cavity at one end of the master cylinder surrounding part of the bore of the primary piston of the master cylinder and to displace fluid therefrom. The primary piston is constructed to move simultaneously within its bore and to displace fluid therefrom to initiate movement of the secondary piston.

Abstract: A slip control hydraulic brake system for wheel brakes wherein a sliding booster piston and a second piston form a working chamber with hydraulic pressure that acts upon a wheel brake. The booster piston and the brake system housing form two annular chambers, the second annular housing chamber larger than the first, whereby upon actuating travel of the booster piston the first annular housing chamber increases in volume and the second annular housing chamber decreases in volume.

Abstract: A blow-off valve in the quick take-up master cylinder comprises first and second valves therein. The first valve is responsive to the fluid pressure built up in a primary pressure chamber. The second valve includes a valve member urged towards a valve seat thereof. The force urging the valve member of the second valve is adjustable according to the position of the first valve.

Abstract: A master cylinder includes a housing with a pair of pistons movable therein to develop fluid pressure in a pair of pressure chambers. One of the pistons carries a seal assembly in order to provide a fast-fill feature. The seal assembly engages a large diameter section during initial braking and separates therefrom after a predetermined fluid pressure level is reached so that the one piston moves relative to a small diameter section to continue fluid pressure buildup during braking.

Abstract: In a master cylinder assembly comprising two pedal-operated master cylinders, each master cylinder comprises a pedal-operated piston of stepped outline working in a complementary stepped bore in a housing and having an inner end of smaller area carrying a first seal and an outer end of greater area carrying a second seal, a pressure space in the bore in advance of the inner end of the piston, a quick-fill chamber defined in the bore between the inner and outer ends of the piston, a normally-open recuperation valve providing communication between a reservoir for fluid and the pressure space at least when the piston is in a retracted position, and a normally-closed pressure-limiting valve assembly between the quick-fill chamber and the same or a second reservoir.

Abstract: A fast-fill master cylinder (14) includes a housing (26) defining a bore (38) therein having a portion (y) thereof of substantially constant diameter. A primary piston (54) is movably received in the bore portion (y) and a secondary piston (56) is movably received in the remainder of the bore (38). The secondary piston (56) cooperates with the housing (26) to define a secondary variable-volume chamber (62). The primary piston (54) cooperates with the housing (26) and with the secondary piston (56) to define aprimary variable-volume chamber (58). The primary piston also cooperates with the housing to define a constant-volume recess (84) circumscribing the piston (54). An annular partition member (94) circumscribes the piston member (54) within the recess (84) to divide the recess (84) into a pair of variable-volume compartments (108, 110). A bore 120 communicates the one compartment (110) with the primary chamber (58).

Abstract: A fast-fill master cylinder with integral proportioning includes a housing with a stepped bore defining a large diameter and a small diameter. A piston is disposed with the large diameter and the small diameter to form a fast-fill chamber in the large diameter and a pressure chamber in the small diameter. A passage extends between the fast-fill chamber and an outlet port to bypass the pressure chamber.

Abstract: A compensation control and blow-off valve unit in a quick take-up master cylinder. In one embodiment, a stamped valve body forms a valve member within a valve chamber which permits compensation flow from the master cylinder reservoir to the pressurizing chambers. It has an O-ring seal controlling a passage from the valve chamber to the reservoir which opens the passage at a predetermined quick take-up pressure to return fluid to the reservoir. Other embodiments use an umbrella valve or a spring biased ball check valve. The valve housing in some embodiments also retains the reservoir housing in sealed position on the master cylinder housing.

Abstract: A master cylinder is provided on the cylinder body with a reservoir-receiving mouth formed near the border of the section of of a large diameter and the section of a small diameter of a stepped bore, a through hole being formed between the bottom surface of the reservoir-receiving mouth and the first pressure chamber, a compensation hole being formed between the bottom surface of the reservoir-receiving mouth and the second pressure chamber, a valve seat fitted in and fixed to the reservoir-receiving mouth and having an internal hole formed therein, a check valve provided within the reservoir-receiving mouth between the bottom surface of the reservoir-receiving mouth and the valve seat with the valve element being pressed against a resilient member fixed to the valve seat by means of a spring, a projecting member protruding into the first pressure chamber through the through hole provided for the valve element coaxially with the valve element so that the valve element is titlted to form a passage between the

Abstract: A master cylinder, according to the present invention comprises a primary piston and a secondary piston disposed within a bore of a cylinder housing in tandem relationship. The secondary piston has a sectional area facing to a secondary pressure chamber, which area is smaller than that of the primary piston facing a primary pressure chamber. The hydraulic pressure in the secondary chamber is regulated by a regulator valve means provided opposing thereto. The regulator valve means becomes operative when the hydraulic pressure applied to the secondary pressure chamber exceeds a predetermined value. Due to the difference of the sectional area between the primary piston and the secondary piston which respectively face to the primary and secondary pressure chambers, hydraulic pressure to be applied to the front and rear wheel cylinders is varied to reduce the pressure in the rear wheel cylinder for preventing skidding of the vehicle.

Abstract: A two-stage, hydro-pneumatic actuator suitable for use as a railway vehicle brake. The hydraulic cylinder comprises a large diameter bore in which a low- and a high-pressure piston operate jointly during a first stage of operation to effect a high volumetric displacement of hydraulic fluid via a small diameter bore in order to take up the clearance between the brake shoes and wheel. As the brake shoes contact the wheel, the high-pressure piston enters the small bore to interrupt further displacement of hydraulic fluid from the large bore. The force of the high-pressure piston alone during this second stage of operation produces the required brake forces with a high multiplication factor. Make-up fluid is drawn into a chamber on the backside of the low-pressure piston during a brake application stroke an amount corresponding to the over-travel of the high-pressure piston and is subsequently discharged into the hydraulic cylinder during retraction of the brakes to compensate for brake shoe wear.

Abstract: A master cylinder includes a sleeve (31) which defines fixed positions for a pair of seals (30, 32). A pair of pistons (36, 38) cooperate with the seals (30, 32) to form pressure chambers (40, 42) which communicate fluid pressure to brake circuits during braking. A bearing member (44) cooperates with one (36) of the pistons to define an auxiliary pressure chamber (50) and the bearing member (44) is provided with an additional passage (140) for communicating fluid into and out of the auxiliary pressure chamber as well as an end (46) directing movement of the one piston (36).

Abstract: A differential master cylinder adapted for use as fluid pressure generating source in a brake system comprises a cylinder body having a stepped cylinder formed therein; a stepped piston arranged to be slidable within the stepped cylinder; a first chamber defined by the end of a portion of smaller diameter of the stepped piston and a portion of smaller diameter of the stepped cylinder; a second chamber defined by the stepped piston and a portion of larger diameter of the stepped cylinder; a first fluid passage provided at the stepped piston and arranged to have the first and second chambers intercommunicate; a check valve arranged in the first fluid passage to close when fluid pressure within the second chamber reaches a first setting value; and a relief valve arranged to open to return the fluid from the second chamber to a reservoir when the fluid pressure within the second chamber reaches a second setting value which is higher than the first value.

Abstract: A master cylinder assembly has a low pressure, high volume displacement quick take-up chamber and a high pressure, low volume displacement pressurizing chamber formed by a stepped bore and a stepped piston. A compensation control and blow-off valve unit has a peripheral lip seal type valve providing compensation flow on brake release but preventing flow from the quick take-up chamber during brake apply. A valve body is integrally molded as a part of the reservoir. A normally closed check valve can open to provide communication between the quick take-up pressurizing chamber and the fluid reservoir. When the pressurizing cup for the high pressure chamber closes its compensation port, the check valve is subjected to the pressure in the quick take-up pressurizing chamber. Initial fluid flow is obtained from the quick take-up chamber past the pressurizing cup into the high pressure chamber.

Abstract: A master cylinder assembly has a low pressure, high volume displacement quick take-up chamber and a high pressure, low volume displacement pressurizing chamber formed by a stepped bore and a stepped piston. A compensation control and blow-off valve unit has a peripheral lip seal type valve providing compensation flow on brake release but preventing flow from the quick take-up chamber during brake apply. A normally closed check valve can open to provide communication between the quick take-up pressurizing chamber and the fluid reservoir. When the pressurizing cup for the high pressure chamber closes its compensation port, the check valve is subjected to the pressure in the quick take-up pressurizing chamber. Initial fluid flow is obtained from the quick take-up chamber past the pressurizing cup into the high pressure chamber.

Abstract: A master cylinder includes a housing defining a reservoir and a bore for movably receiving a pair of pistons. A primary piston cooperates with a secondary piston to define a primary chamber therebetween and cooperates with the housing to substantially define an auxiliary chamber. The primary chamber and auxiliary chamber are disposed within a substantially uniform diameter section of the housing bore. The primary piston is movable within the bore to communicate fluid pressure from the auxiliary chamber to the primary chamber until a predetermined pressure level is reached in the primary chamber whereupon the auxiliary chamber is vented to the reservoir. A sealing member disposed within a recess on the bore cooperates with the piston to define the auxiliary chamber. Upon initial movement of the piston relative to the sealing member, a small portion of the fluid within the auxiliary chamber is communicated to the reservoir so as to bleed the auxiliary chamber.

Abstract: A brake master cylinder, having a body, with an attached brake booster which includes first and second pneumatic pressure chambers provided in a booster housing, a power piston defining the first and second chamber therebetween, a first valve mechanism provided within the power piston and generating a pressure difference between the first and second chambers in response to the operation of an associated brake pedal, first and second hydraulic pressure chambers provided in the master cylinder body, a primary piston disposed in the first hydraulic pressure chamber operably connected to the power piston, a first passage member communicating the second hydraulic pressure chamber with a brake wheel cylinder, a second passage member communicating the first hydraulic pressure chamber with a reservoir, a second valve mechanism controlling the communication between the second passage member and the reservoir upon slidable movement with the primary piston, a third valve mechanism provided within the primary piston and

Abstract: A master cylinder includes a housing defining a reservoir containing fluid. A bore within the housing communicates with the reservoir and movably receives a pair of pistons which substantially define a pair of pressure chambers. One of the pistons includes a cavity movably receiving a position sensitive piston which cooperates with the one piston to define an auxiliary pressure chamber. When the one piston is moved during a brake application, the position sensitive piston is movable relative to the one piston to generate fluid pressure within the auxiliary pressure chamber. A passage between the auxiliary pressure chamber and one of the pair of pressure chambers provides one way communication between the auxiliary and one pressure chambers.

Abstract: A brake master cylinder device includes a first and a second cylinder bore formed within a body. A piston member is formed with a first piston and a second piston, which are respectively engaged with the first and the second cylinder bores to define a first and a second cylinder chamber, the arrangement being such that when the piston member is moved in a certain direction the volumes of both the first and the second cylinder chambers are reduced together. The piston member is biased in the direction opposite to said certain direction. A fluid conduit opens from the second cylinder chamber for connection to a brake actuator. A means for transferring fluid allows brake fluid to pass substantially freely from the first cylinder chamber to the second cylinder chamber. A fluid accumulator is communicated with the first cylinder chamber, and commences to accumulate fluid from it when the pressure in it rises to a predetermined pressure value.

Abstract: A quick take-up valve in a quick take-up master cylinder assembly which reduces fluid flow noise and restriction caused by fluid flowing in one mode of operation through an incipiently or substantially closed valve spring coil stack. The check valve arrangement has a coil compression limiting device and also has the outlet orifice so positioned as not to require fluid flow through the check valve spring coils while the check valve is open.

Abstract: A split-type brake master cylinder for motor vehicles comprises a stepped bore, a stepped primary piston to constitute a first fluid chamber between a large diameter portion and a small diameter portion thereof, a secondary piston to form a primary pressure chamber in cooperation with the primary piston as well as a second fluid chamber in normal fluidic communication with a reservoir, and a compensation port continuously connected to the primary pressure chamber and in the fluidic connection to the second fluid chamber at the brake release condition while in the fluidic isolation therefrom at the brake application. Thus, the compensation port has no direct relationship with the pressure increase in the first fluid chamber thereby to assure the stable output pressure of the master cylinder regardless of the depression speed of brake pedal.

Abstract: A compound master brake cylinder assembly (10) for a braking system, the cylinder assembly having a reservoir (34), a first low pressure cylinder (72), and a removable high pressure cylinder (58). A relief valve (84) is provided with a poppet valve (104) normally biased to a closed position. The relief valve (84) extends between the low pressure cylinder (72) and reservoir (34) and is responsive to first cylinder (72) pressure and outlet pressure through pilot passageways (114 and 111, respectively) to vent fluid from cylinder (72) to reservoir (34) to progressively reduce the pressure in the cylinder to insure that the force applied by push rod (14) does not substantially vary while cylinder (72) pressure is being reduced after outlet pressure exceeds a predetermined position.

Abstract: The present invention relates to a brake master cylinder device including a first and a second cylinder bore formed within a body. A piston member is formed with a first piston and a second piston, which are respectively engaged with the first and the second cylinder bores to define a first and a second cylinder chamber, the arrangement being such that when the piston member is moved in a certain direction the volumes of both the first and the second cylinder chambers are reduced together. The piston member is biased in the direction opposite to said certain direction. A fluid conduit opens from the second cylinder chamber for connection to a brake actuator. A first one way valve always allows fluid to flow freely from the first to the second cylinder chamber. A second one way valve allows fluid to flow from a fluid reservoir, within which fluid is kept at atmospheric pressure, to the first cylinder chamber, when the pressure in the first cylinder chamber is below atmospheric pressure.

Abstract: In a master cylinder a housing defines a bore for movably receiving a pair of pistons. A pair of seals cooperate with the pair of pistons to define a pair of pressure chambers and a sleeve disposed within the bore fixedly locates the pair of seals within the bore so that when the pair of pistons are moved within the bore, the pair of pistons move relative to the pair of seals to displace fluid within the pressure chambers to respective brake circuits. A bearing member engages the sleeve to fixedly retain the sleeve within the bore and cooperates with one of the pair of pistons to define an auxiliary chamber which is contracted during a brake application to communicate fluid to one of the pair of pressure chambers.

Abstract: A fluid pressure intensifier in which a body has a side wall and first and second end walls. A tube extends inwardly in the body from the first end wall and a piston head is slidably disposed on the tube. A cylindrical element in spaced relation to the body side wall extends from the piston head toward the second end wall. A fluid inlet in the second end wall supplies pressurized fluid to move the piston head on the tube. A fluid outlet through the tube transfers pressurized fluid from within the element out of the intensifier. The amount of pressure intensification is proportional to the surface area differential of the piston head and a cross section of the element.

Abstract: A two step pressure intensifier system consisting of three piston-cylinder units in coaxial arrangement, the first unit being a low pressure medium supplied to it to jointly move the pistons of all the units. The initial movement employing the second unit for a moderate pressure increase and the final movement bringing the piston of the third unit into its cylinder for a high pressure increase.

Abstract: A two-stage intensifier system for use in conjunction with a pressure-operable swing clamp or other pressure-operable device for supplying fluid pressure at a relatively low pressure to perform a first operation and thereafter to supply fluid pressure at a higher pressure to perform a second operation.

Abstract: A master cylinder assembly has a low pressure, high volume displacement quick take-up chamber and a high pressure, low volume displacement pressurizing chamber formed by a stepped bore and a stepped piston. A compensation control and blow-off valve unit has a peripheral lip seal type valve providing compensation flow on brake release but preventing flow from the quick take-up chamber during brake apply. A normally closed check valve can open to provide communication between the quick take-up pressurizing chamber and the fluid reservoir. When the pressurizing cup for the high pressure chamber closes its compensation port, the check valve is subjected to the pressure in the quick take-up pressurizing chamber. Initial fluid flow is obtained from the quick take-up chamber past the pressurizing cup into the high pressure chamber.

Abstract: A tandem master cylinder for a vehicle split hydraulic braking system which has disc brakes in one half of the system and drum brakes in the other. One of the pistons in the master cylinder is prevented from developing a substantial pressure until a predetermined pressure has been developed by the other piston by virtue of a quantity of fluid trapped in a control chamber by a control piston. First and second valve means control the pressure in the control chamber. The valve means include a plunger which initially moves against a first control spring to allow a valve member to seat and trap the fluid in the control chamber and subsequently moves away from the valve member under an increased pressure in the control chamber against a second control spring to release the trapped fluid.

Abstract: A tandem master cylinder for a vehicle split hydraulic braking system which has disc brakes in one part of the system and drum brakes in the other half. One of the pistons in the master cylinder is prevented from developing a substantial pressure until a predetermined pressure is developed by the other piston by virtue of a control piston working in a blind bore in one of the pistons. Hydraulic fluid is trapped in a control chamber formed by the blind bore and the control piston by a first valve means and released by a second valve means at the predetermined pressure. The arrangement allows pressure to the disc brakes to be delayed while pressure to the drum brakes is overcoming the effects of the usual pull-off springs.

Abstract: A control member responsive to a predetermined operational pressure signal for transferring that portion of an input force acting on a first diameter of a pressurizing piston in a two stage servomotor to a second diameter. The input force acts on the pressurizing piston and moves the second diameter section thereof in an outlet chamber to further pressurize the fluid therein and meet an operational demand associated with the input force.

Abstract: A master cylinder assembly has a low pressure, high volume displacement quick take-up chamber and a high pressure, low volume displacement pressurizing chamber formed by a stepped bore and a stepped piston. A compensation control and blow-off valve unit has a peripheral lip seal type valve providing compensation flow on break release but preventing flow from the quick take-up chamber during brake apply. A normally closed check valve is held open while the master cylinder is in the fully released position to provide communication between both pressurizing chambers and the fluid reservoir. As the pressurizing cup for the high pressure chamber closes its compensation port, the check valve is permitted to close by camming action of a valve pin and a camming surface on the piston. Initial flow is obtained from the quick take-up chamber past the pressurizing cup into the high pressure chamber.

Abstract: The invention relates to a master-cylinder having a two-part cylinder, one part being of narrower diameter than the other, and a two-part piston slidable in the cylinder. Two pressure chambers are defined by the cylinder and the piston. Advance of the piston reduces the volume of both. One, the high pressure chamber feeds an external pressure system, and is itself fed by the other chamber through a valve system during an initial phase of the piston stroke. In a later phase the feed from the second in the first chamber ceases and instead the second chamber feeds the fluid reservoir through a control valve. Pressure-transmitting means such as a rod is arranged between the high pressure chamber and the control valve to open the control valve when the pressure in the high pressure chamber exceeds a predetermined value.