Abstract: A master cylinder assembly in which the casing defines an annular seal groove defining a forward bore portion forwardly of the annular groove and a rearward bore portion rearwardly of the annular groove. The front end of the piston in the retracted position of the piston is received in the forward bore portion to provide total bearing support for the piston and axial grooves are provided in the forward bore portion to allow recuperative fluid to flow from the associated reservoir and through the axial grooves to the forward bore portion forwardly of the retreating piston.

Abstract: A master cylinder for use in the power train of a motor vehicle to actuate the brakes or the friction clutch is designed to avoid the generation of screeching noise and/or the transmission of stray movements to the piston rod in response to shifting of the piston relative to the housing and relative to the sealing element(s) between the piston and the housing. This can be accomplished by causing the piston to turn relative to the housing and the sealing element(s) during axial movement in the housing and/or by installing one or more dampers between the piston and the housing and/or between the piston and the piston rod. The dampers can constitute separately produced parts and/or specially configured and/or finished surfaces provided on the piston and contacting the housing and/or the sealing element(s). The invention also relates to improvements in the configuration and/or the material(s) of the piston.

Abstract: The invention relates to a vehicle hydraulic brake system with electrohydraulic brake boosting by a piston pump. In order to reduce pressure pulsations on an intake side of the multi-piston pump, the brake system embodies a multi-piston pump, for example, as a six-piston pump with stepped pistons that are driven with an alternating phase shift of 30° and 90° in relation to one another. The phase shift of the drive of the stepped pistons is selected so that the intake volume flows have a uniform phase shift, by which the total intake volume flow of the multi-piston pump has a reduced amplitude of the pressure pulsation, which reduces the repercussions on a master cylinder.

Abstract: A master cylinder for use in the power train of a motor vehicle to actuate the brakes or the friction clutch is designed to avoid the generation of screeching noise and/or the transmission of stray movements to the piston rod in response to shifting of the piston relative to the housing and relative to the sealing element(s) between the piston and the housing. This can be accomplished by causing the piston to turn relative to the housing and the sealing element(s) during axial movement in the housing and/or by installing one or more dampers between the piston and the housing and/or between the piston and the piston rod. The dampers can constitute separately produced parts and/or specially configured and/or finished surfaces provided on the piston and contacting the housing and/or the sealing element(s). The invention also relates to improvements in the configuration and/or the material(s) of the piston.

Abstract: In the rotary pump, a high pressure outer circumference chamber, which is formed around an outer circumference of an outer rotor and communicates with a discharge port, presses radially inward first defined parts among the outer circumference of the outer rotor that are positioned radially outside second defined parts adjacent to teeth gap portions whose volume are largest and smallest among teeth gap portions communicating with an intake port. Teeth top clearance between the outer and inner rotors at the second defined part is reduced due to pressure difference between the discharge pressure applied to the first defined parts and the intake pressure applied to the second defined parts.

Abstract: A master cylinder of the present invention comprises a cylinder having one end open to the outside. A secondary piston guide ring, a sleeve and a primary piston guide ring are adapted to be fitted in this order into the cylinder from the one open end. A piston is slidable fitted in an axial direction of the cylinder, into each of the secondary piston guide ring, the sleeve and the primary piston guide ring. A retaining means is provided at the open end of the cylinder, and adapted to abut against the primary piston guide ring and prevent escape of the primary piston guide ring from the cylinder. An elastic member is provided between a rearward end portion of the sleeve and a forward end portion of the primary piston guide ring.

Abstract: An air booster system (10) for use with a gas turbine to deliver compressed air to a combustion chamber (14) includes a first cylinder (24) with a first piston (52) reciprocal therein and a second cylinder (26) having a second piston (54) reciprocal therein. The first piston (52) is connected to the second piston (54) by a connecting rod (56) such that the first and second pistons (52, 54) reciprocate together. The air booster system (10) also includes a third cylinder (28) having a third piston (58) reciprocal therein and a fourth cylinder (30) having a fourth piston (60) reciprocal therein. The third piston (58) is connected to the fourth piston (60) by a connecting rod (62) such that the third piston (58) and the fourth piston (60) reciprocate together. Each of the cylinders (24, 26, 28, 30) are in fluid communication with a compressor (12) to receive preliminarily compressed air therefrom.

Abstract: A master cylinder includes a cylinder housing having a rearwardly opening inner bore, a piston having a forwardly opening bore positioned in the inner bore of the cylinder housing, a spring disposed in the inner bore of the piston, a stopper supporting a front end of the spring, a retainer disposed in the inner bore of the piston and supporting a rear end of the spring, and a rod connecting the retainer and the stopper while allowing the spring to compress in the axial direction. A plurality of projection portions are formed on the outer circumferential portion of the retainer and the retainer is pressed into the inner bore of the piston via the projection portions.

Abstract: In a master cylinder device for a vehicle having a master cylinder with a cylinder body attached in the vicinity of a grip of a steering bar handle, and an operating lever which is supported on the cylinder body through a pivot and is pulled toward the grip to thereby push a piston of the master cylinder, the cylinder body is mounted in such a position that, below the axis of the bar handle, the axis of the cylinder body is substantially orthogonal to a vertical plane which includes the axis of the bar handle, whereby the master cylinder can be mounted even in a narrow space on the bar handle in a motorcycle and the like having a steering bar handle.

Abstract: A force transmission and amplification device for a brake system comprising a pedal (1) and an output rod (2) for transmitting by way of the output rod (2) an output force (F2) having a higher intensity than an input force (F1) applied to pedal (1). An input rod (3) is secured to the pedal (1) for supplying a primary piston (4) located in a first diameter (D1) of primary cylinder (5) to delimit a primary chamber (51) retaining a fluid. A second piston (6) secured to the output rod (2) is located in a second diameter (D2) of a second cylinder (7) to delimit a secondary chamber (71). The primary chamber (51) is connected to the secondary chamber (71) to immediately supply pressurized fluid which acts on the second piston (6) to develop the output force (F2).

Abstract: The invention relates to a master cylinder with hydraulic reaction, comprising a working chamber (12) in which there slides, under the action of a pushrod (50), a hollow main piston (13) inside which a reaction piston (14), itself moved by a plunger (80), delimits a reaction chamber (15) which communicates with the working chamber (12), a prestressed spring (16) offering resistance to a movement of the reaction piston (14) in the opposite direction (X+X−) from its actuating direction (X−X+). According to the invention, a sliding ring (18) is arranged opposite the plunger (80) so that actuation of the reaction piston (14) by the plunger (80) is also accompanied by compression of the spring (16).

Abstract: A clutch-actuating device includes a master cylinder actuated by depression of a clutch pedal, an operating cylinder actuated by fluid pressure fed from the master cylinder through a conduit which is connected to the master cylinder or the operating cylinder via a coupling member, and a restriction mechanism for restricting the flow of hydraulic fluid returning from the operating cylinder to the master cylinder, the restriction mechanism being incorporated in the coupling member. The operating cylinder (or master cylinder) of this clutch-actuating device can be commonly used regardless of whether a torque shock protection valve should be incorporated.

Abstract: A control device for a cylinder (1) is provided with an entrance (4) which is connectable to a pressure source and with an exit (5) which is connectable to the cylinder (1) that is controllable by means of the pressure source. The device (2) comprises means (6 to 12) for defining an intermediate position, not being one of the end positions, in the stroke of the cylinder piston (3). Thus a large number of options for use and application possibilities for the cylinder (1) can be realized in a simple, compact and cheap manner.

Abstract: A foot pedal (12, 42) for controlling operation of a vehicle is supported for movement relative to the vehicle. A cushion (22, 60), inflatable by inflation fluid, is connected with and, when inflated, extends from the pedal (12, 42).

Abstract: An hydraulic system that includes a master cylinder, a slave cylinder, a fluid conduit extending between the cylinders, and a pressure relief valve within the conduit between the cylinders. The pressure relief valve includes at least one port that is closed by an elastic member that overlies the port and that opens when fluid pressure acting through the port exceeds a predetermined level to cause the elastic member to open the port.

Abstract: A master cylinder (10) for a hydraulic vehicle brake system has a housing (34) and a bore (36) which is disposed therein and in which a hollow cylindrical primary piston (38), which acts on a pressure chamber (40), is guided in a sealing and axially displaceable manner. An axially displaceable, hollow cylindrical auxiliary piston (42) is accommodated in the primary piston (38), into which piston (42) an actuating piston (46) projects, which piston (46) is adapted to be actuated by means of an input member (24), is is guided in a sealing and displaceable manner in the auxiliary piston (42) and is resiliently preloaded away from the latter at least during braking. The actuating piston (46) has a first hydraulically active diameter (D1) and the auxiliary piston (42) has a second hydraulically active diameter (D2). The auxiliary piston (42) is rigidly coupled to the actuating piston (46) after covering a determined distance against its resilient preload.

Abstract: A front brake master cylinder relocation kit which may be used for example on Harley-Davidson.RTM. motorcycles. The kit includes a master cylinder; a brake cable; a hand lever capable of being mounted on a handlebar; a brake hose; a mounting bracket, for mounting the master cylinder on a motorcycle; and a package for accommodating the master cylinder, the brake cable, the hand lever, the brake hose, and the mounting bracket. The master cylinder includes a brake cable connector; an actuator lever; an actuator device, operatively connected to the actuator lever; an oil container inside the master cylinder for accommodating hydraulic oil; and a brake hose connector operatively connected to the oil container. The package may be provided with assembly instructions for the kit.

Abstract: A hydraulically-operated micromanipulator apparatus is disclosed.

Abstract: A push rod of a vacuum booster includes an inner rod section, a pipe-shaped outer rod section which is slidably fitted over an outer periphery of a rear portion of the inner rod section and connected to a brake pedal, and a buffer member made of a synthetic resin and fitted over the outer periphery of the inner rod section in front of the outer rod section. Usually, an end face of the outer rod section is retained in a position in which it abuts against a projection of the inner rod section. When an axial compressing force is applied to the push rod upon a collision of an automobile, the end face of the outer rod section slides forwards over and past the projection, while buckling the buffer member. Thus, the pushing-up of the brake pedal toward a vehicle compartment due to the retreating movement of a master cylinder is prevented, and the load applied to a driver's foot is alleviated.

Abstract: An improved braking system includes a valving arrangement which permits reduction of deadband regardless of a randomly selectable piston home position or permits adjustment of the deadband. The system includes a fluid reservoir, a piston located in a cylinder including a reservoir port, a first fluid channel connecting the reservoir to the reservoir port, a brake actuator, and a second fluid channel connecting the cylinder to the brake actuator. The piston is moveable within the cylinder to produce fluid flow within the first channel. A first valve is disposed between the reservoir and the cylinder to prevent fluid flow from the cylinder to the reservoir when the piston is moved to pressurize fluid in the second fluid channel.

Abstract: According to the present invention, the master cylinder of a motor vehicle actuating unit has a bipartite flange, and one part of the flange is provided as a mounting plate which is guided on a spherical bead shaped on the master cylinder. The mounting plate clamps the master cylinder in relation to the wall of a brake force booster. This ensures that the master cylinder may escape or may be deflected in a rearward direction in the case of a crash, without transmitting an excessively large amount of force to the wall of the brake force booster.

Abstract: A master cylinder (10) for a hydraulic vehicle braking system comprises a housing (12) which has a bore (14) extending along a longitudinal axis (A), whose one end is closed by an end wall associated with the housing (12) of the master cylinder (10) and whose other opposite end is sealingly closed by a closure element (16). In the bore (14) adjacent to the closure element (16) a piston (18) is accommodated sealingly and axially movable which can be actuated through same, which has a central valve (20) which enables a fluid connection between a fluid reservoir and a pressure chamber (28) which is defined in the bore (14) by the end wall and the piston (18). When the piston (18) is not actuated, the central valve (20) is held in the open position by means of an abutment member (transverse pin 34) acting on the closure element (16).

Abstract: A brake-control device having a vacuum booster (1), a master cylinder (2) and an electro-hydraulic module (3) for controlling brake pressure. The booster (1) has a front shell (10) and a rear shell (11) having a cylindro-frustroconcal shape with first (R10) and second (R11) outsider radii. The master cylinder (2) and module (3) being secured to the front shell (10) at least three fixing points (71, 72, 73). The fixing points defining a peripheral ring (100) on the front shell which is delimited by an inside radius (Ri) that is equal to half of the outside radius (R10) of the front shell (10).

Abstract: A hydraulically-operated micromanipulator apparatus is disclosed.

Abstract: For an automatic hydraulic pressure generator in which a hydraulic master cylinder driven by a computer-controlled motor lets in or takes out a friction clutch, an operation device is provided that can make the piston rod of the hydraulic master cylinder operate at high torque and at high speed and further that is advantageous in durability of its conversion mechanism from rotary motion to linear motion.

Abstract: To provide a hydraulic master cylinder with inlet ports and outlet ports arranged in an angle to each other wherein the outlet ports can be on either side of the housing without the need of two different casts, the master cylinder according to the invention is equipped with either two sets of protrusions adapted to be machined into inlet ports or two sets of protrusions adapted to be machined into outlet ports. The two sets of identical protrusions are arranged symmetrically with respect to the one set of different protrusions. Thus, depending on the desired side of the outlet ports, only one set of the two sets of identical protrusions is machined while the other set remains an unmachined accumulation of material.

Abstract: A brake system includes a pedal feel emulator and a master cylinder with a damping mechanism having a damping piston. When the emulator piston is moved from the at-rest position, fluid is displaced from the emulator through a compensation port and through a flow restrictive orifice in the damping piston to the reservoir. Flow rate of the fluid is dependent on the apply rate of the brake pedal. When the brake pedal is applied relatively slowly, sufficient flow volume will occur through the flow restrictive orifice and the damping piston will remain unmoved. As apply rates increase, a sufficient pressure differential will eventually be established across the damping piston to cause it to move. Damping piston movement compensates for rapid fluid displacement out of the variable chamber and enables a desirable pedal feel characteristic where pedal force increases relatively slowly as pedal velocity increases relatively rapidly.

Abstract: A master cylinder for a hydraulic friction clutch, said master cylinder being connected to a physically actuatable pedal by a piston rod (17) which is articulated in semi-shells (14) enclosed in a piston skirt bushing (10), an end of said piston skirt bushing (10) remote from the piston rod (17) being connected to a piston (7) which is longitudinally displaceable in a guide sleeve (96) of the master cylinder (1), an end face of said piston (7) delimiting a pressure chamber (8) wherein the semi-shells (14) fill an inner space of the piston skirt bushing (10) without play and comprise a cup-shaped recess (15) in which a ball head (16) of the piston rod (17) is retained by positive locking, the piston skirt bushing (10) forming a structural unit with the radially stepped piston (7).

Abstract: A master cylinder for attachment with a pre-installed brake booster includes a housing having a bore to receive a piston and piston rod. An outermost end of the piston rod has a guide member in the shape of a funnel which centrally aligns a push rod in the brake booster with a blind bore in the piston rod during attachment with the booster. In addition, a sealing boot is provided on the master cylinder to protect the piston rod outer sealing surface from foreign material and foreign objects that would otherwise contact the piston rod surface during shipping, storage, and installation. The sealing boot is attached at one end to the housing and at an opposite end to the guide member.

Abstract: A boosted braking system for a motor vehicle having a master cylinder (200) and a pneumatic booster (100). The master cylinder (200) causes an increase in pressure of brake fluid supplied to at least one wheel brake (300). The pneumatic booster (100) is controlled by the application of an input force (F2) to a control rod (26) to actuate the master cylinder (200). A main hydraulic piston (30) of the master cylinder (200) has a hollow cylinder (32) in which a reaction piston (34) slides in a leaktight and axial direction. The reaction piston (34) receives at least the input force (F2). An elastic member (46) located between the reaction piston (34) and hollow cylinder (32) exerts an elastic force for urging the reaction piston (34) toward the master cylinder (200). The reaction piston (34) delimits within the cylinder a reaction chamber (36) which is isolated from the interior volume (V) of the master cylinder (200).

Abstract: An actuator system (31) for controlling engagement and disengagement of an automated vehicular master clutch (C). The system includes an electric motor (86) controlled actuator (62) for precision positioning of the clutch and a pneumatically controlled override actuator (54) for rapidly disengaging the clutch, regardless of positioning of the electric motor-controlled actuator. Both the electric motor-controlled actuator and the pneumatically controlled override actuator are operated in accordance with command output signals from a system control unit (31).

Abstract: A master cylinder comprising a cylindrical body (1) which points along a main axis (X). The cylindrical body (1) has a free end (11) and an attached end (12) with a piston rod (2) extending axially from the attached end (12). An impact deflector (3) removably mounted on the cylindrical body (1) covers the free end (11). The impact deflector (3) has at least one deflecting surface (D) which is inclined obliquely to the main axis (X).

Abstract: The present invention is directed to a throttle control device to be used in combination with an engine having a throttle and a pump driven by the engine. The automatic control device has a housing defining a chamber having a first opening adapted to receive a fluid containing conduit in communication with the pump. A piston is slideably mounted in the chamber and has a first end acted on by a fluid contained in the conduit. A spring surrounds a portion of the piston within the chamber and biases the piston towards the first opening and, therefore, the fluid. A second end of the piston extends through a second opening in the chamber and controls the throttle. A first adjustable stop in the chamber limits travel of the piston and a second adjustable stop controls the compression of the spring.

Abstract: A brake pedal feel emulator includes a piston that is movable against the force of a compressible elastomeric body and fluid force. The emulator supplies conventional pedal feel and travel characteristics when the primary and secondary pistons of the brake system's master cylinder are substantially movable due to isolation of the master cylinder from the wheel brakes. The fluid force is supplied by controlling the flow of fluid from behind the emulator piston through a flow restrictive orifice to a conventional fluid reservoir on the master cylinder assembly. The emulator is operable with electric or electro-hydraulically controlled braking system.

Abstract: The present invention describes an apparatus for achieving power amplification in general press and elevating systems with enhanced control and without the disadvantages of the pneumatic and angle-linked devices. A motor is coupled to a screw and nut for delivering force to at least one transfer piston within a fixed volume at the base of a larger piston. Amplification of power is attained when transfer piston displaces the fluid within the fixed volume. A pressure sensor in the fixed volume and coupled to the motor provides the closed loop feedback required of the control of power amplification. The change in force exerted by the transfer piston has linear relationship with the change in power output of the larger piston.

Abstract: The improved clutch of the present invention includes a fluid actuated piston in the pressure plate assembly which may selectively and gradually be moved into and out of position to engage and disengaege the clutch plate between the pressure plate assembly and the flywheel. The improved clutch also includes a fluid actuator circuit to control the selective and gradual engagement of the clutch assembly.

Abstract: A double acting reciprocating intensifier uses a single low pressure fluid stream as both the power supply and the source of fluid the pressure of which is to be intensified. The entire device, including flow paths, is confined within a compact cylindrical housing. Tandem drive pistons minimize operating frequency, while maximizing intensification ratio and output volume flowrate. Placement of both high pressure cylinders downstream of the drive cylinders permits simple routing of flows through the centers of the low and high pressure pistons. A check valve connected between the high pressure pistons eliminates one of the four high pressure check valves required in the prior art. A single reciprocating valve, whose state is determined by drive and high pressure piston position, coordinates all of the drive side flows. Various components perform multiple functions to permit the compact shape.

Abstract: The master cylinder of the present invention is provided with the bearing in which a bearing body includes the inner circumferencial seal groove which is formed with a L-shape in longitudinal section with one side surface thereof opened, and a set plate is secured to an end surface of the bearing body so as to close the opened side surface of the inner circumferencial seal groove, wherein the set plate has a plurality of engaging pawls formed thereon for resiliently to pressing the bearing body onto a stopper ring or pressing the bearing body onto a step portion between a cylinder hole and the bearing housing while elastically holding the bearing body, whereby the seal member can easily be fitted into an inner circumferencial seal groove, of a bearing while preventing the bearing from chattering and preventing the seal member from being deformed seriously.

Abstract: A clutch pedal dashpot for controlling the rate torque is applied to a vehicular driveline during the coupling of an engine to a transmission by controlling the rate at which the clutch engages via damping clutch pedal travel. The dashpot is for use in a vehicle, such as a heavy-duty truck, which includes a clutch pedal displaced between a resting position and a depressed position. The clutch pedal dashpot includes a damper piston, coupled to the clutch pedal, for controlling the rate at which the clutch pedal returns to the first position from the second position during coupling so as to control the rate of clutch engagement, thereby controlling the rate of torque applied to the driveline.

Abstract: Left and right two stage brake valves communicate fluid pressure to left and right brake mechanisms. Each 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 piston is movable away from a rest position to transfer fluid to the brake mechanism. The stepped bore and the stepped piston form a high volume prefill chamber and a high pressure chamber. The high pressure piston has a groove communicated with the brake mechanism, and the groove communicates with the inlet when the high pressure piston has moved a certain distance to transfer fluid from the high pressure chamber to the brake mechanism. The prefill piston has a sealing land and a second land on either side of a sealing ring which is slidable in the stepped bore.

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 self-adjusting pneumatically operated vehicular master clutch actuator is provided. A pneumatically operated primary actuation piston (1) carries a push/pull rod (7) for operation of a master clutch linkage (22). The push/pull rod (7) is mounted to the primary piston (1) by a hydraulic adjustment assembly (2, 10, 12, 11) for axial movement therewith. Sensing device (4), at least partially interior of the primary cylinder housing (8), for sensing the axial position of the primary actuation piston are also provided.

Abstract: A cap which is so constructed that parts manufacture and product assembly are facilitated. The construction is such that a cap for a master cylinder reservoir connects a cover cap and a body cap with each other and a diaphragm is disposed in a space formed therebetween to provide a valve function. The cover cap has a concentric cylindrical portion and an annular protrusion, while the body cap has a funnel portion at its center and an annular disc portion at the periphery of the funnel portion. The diaphragm is fitted between the inner periphery of annular protrusion of the cover cap and the outer periphery of the funnel portion of the body cap. The diaphragm forms a suction valve and an exhaust valve together with the cylindrical portion and the annular disc portion, respectively.

Abstract: A device for driving a tool in axial direction in the course of a vibration-like forward and reverse movement, which operates at high efficiency with a rapidly oscillating stroke frequency and can be used as an easily handled hand-held appliance because, due to the drive, an especially advantageous ratio of the weight and volume to the power exerted at output is feasible. This drive consists of a piston (8) movable non-positively to and fro, which feeds oil to a working piston (22) and moves the latter correspondingly to and fro against the pressure of a spring (25) acting on the working piston (22) and against the external air pressure. The tool to be drive is preferably connected with the working piston (22) by means of the counterpressure spring (25). Working cylinder (20) and master cylinder (9) are connected with each other by a flexible hose (14) to prevent any weight transmission to the hand-held appliance. (FIG.

Abstract: A displacement magnifying device for magnifying the displacement of a piezoelectric element according to an applied voltage, is applied to a vibration absorber and an actuator. The device includes a member for supporting the element, a first elastic sealing member forming part of a sealed chamber containing a non-compressible fluid which moves together with the other end of the element, a second elastic sealing member also forming part of the chamber, and a displacement transmitting member connected to the second sealing member. Preferably, the first sealing member is a diaphragm and the second sealing member is a bellows. By setting the volume change of the chamber per unit displacement of the first sealing member to be larger than the volume change of the chamber per unit displacement of the second sealing member, the displacement of the piezoelectric element is magnified and transmitted to the displacement transmitting member.

Abstract: A cylinder apparatus capable of effectively restraining a loss of energy with a simple structure at a low cost. When a piston 16 of a main cylinder 11 cuts off a communication between a subchamber 20 and a supply/exhaust passage 32, a pressure of the subchamber 20 is pushed by the piston 16 and thereby increased. However, an exhaust fluid from the subchamber 20 having the increased pressure is fed to a subcylinder 62. A piston 48 is moved while controlling a velocity by a flow rate control valve 70 in synchronization with the piston 16. This arrangement eliminates a necessity for a special position detector, etc.. The structure is therefore simplified, and the cost decreases. Simultaneously, the energy can be effectively utilized because of employing the exhaust fluid.

Abstract: An hydraulic piston and cylinder unit with a piston rod and first and second cylinders. The piston rod extends into the first cylinder, and the first cylinder extends into the second cylinder. The piston rod is connected to a first piston which divides the first cylinder into first and second chambers. A second piston, connected to the first cylinder, divides the second cylinder into first and second chambers. The second chambers of the first cylinder, and the first chamber of the second cylinder are in fluid communication such that an extension of the first cylinder causes a proportional extension of the second cylinder. A similar effect occurs during retraction of the cylinders.

Abstract: An intensifier cylinder including a body structure defining a first bore, a first piston structure including a piston mounted in the first bore and a piston rod secured to the piston and extending at its forward end through an end wall of the body structure, a second bore defined in the body structure, a second piston structure including a second piston mounted in the second bore and a second piston rod secured by the second piston and movable at its forward end into the first bore upon stroking of the second piston in response to the introduction of pressurized gas into the second bore to seal off and act upon hydraulic fluid in the first bore to produce an intensified force on the first piston structure.

Abstract: The master cylinder comprises a body 10 formed with a bore 13, a piston 19 slidable in the bore to discharge hydraulic working fluid from the bore and an annular reservoir 17 for communication with the bore 13 and which is concentric with the bore. The reservoir contains a flexible diaphragm 30 which separate fluid in the reservoir 17 from ambient air. The use of the concentric reservoir 17 and diaphragm 30 makes the master cylinder particulary compact and suitable for use in a pre-filled clutch release system of a vehicle.

Abstract: A hydraulic control apparatus, more particularly for operating a motor vehicle clutch release mechanism, comprising a master cylinder, a slave cylinder and a conduit connecting the master cylinder to the slave cylinder. The apparatus is in the form of separate modular units which are separately filled with hydraulic fluid, and the filled modular units are shipped unconnected to a user. Each modular unit is provided with a leakproof quick-connect connector member, through which filling of the modular unit may be effected, and which mates with a complementary leakproof quick-connect connector member of another modular unit, such that after installation on a utilization device, a motor vehicle for example, complementary connector members are reconnected, thus opening ports in each connector member placing each member in fluid communication with the other. Preferably, the two connector members are provided with a one-way locking arrangement preventing separation of the connector members after coupling.