Abstract: A subsea retrievable pressure sensor for measuring fluid pressure at a well or other subsea fluid system. In one embodiment, a pressure sensor assembly includes a subsea pressure housing, a first pressure sensor, an electrical connector, a first hydraulic connector, and a latching mechanism. The first pressure sensor is disposed within the housing, and the electrical connector and first hydraulic connector are disposed in wall of the housing. The electrical connector is electrically coupled to the first pressure sensor to communicate electrical power though the housing to the first pressure sensor and to communicate pressure measurement values from the first pressure sensor through the housing. The first hydraulic connector is hydraulically coupled to the first pressure sensor to communicate hydraulic pressure to the first pressure sensor through the housing. The latching mechanism extends through the housing to secure the housing to a subsea receptacle.

Abstract: Hydraulic unit adapted for connection to master and slave actuator system includes three valves, the first configured for selective fluid passage between the cap ends, the second configured for selective fluid passage between the slave cap end and an accumulator, and the third fluidly coupled for selective fluid passage between each of a single pump and the accumulator, and the slave cap end. During actuator retraction, the valves permit pressurized fluid in the slave cap end to be delivered to accumulator for storage; during extension, the valves permit pressurized fluid from pump and accumulator to be delivered to the slave cap end.

Abstract: A housing of a master cylinder device includes a housing member separating an interior of the housing into a front and a rear side chambers and having an opening through the housing member. A pressurizing piston includes a main body portion disposed in the front side chamber and is moved forward by a force for pressurizing the brake fluid. An input piston can move forward by an operation force. An input chamber into which a brake fluid from a high pressure source device is introduced is defined between a rear end of the main body portion of the pressurizing piston and the housing member. The input piston is fitted in the housing with seals, whereby, the input piston and the pressure receiving piston face to each other through the opening, though the input piston and the pressure receiving piston are not fitted to each other with any seal.

Abstract: Disclosed is a master cylinder for brake systems including a cylinder body having a bore therein, a first and second piston installed in the bore to move forward and backward, and a first hydraulic pressure chamber and a second hydraulic pressure chamber, the first and second hydraulic pressure chambers being divided from each other in the bore. The master cylinder further includes a pressure regulating channel to connect the first hydraulic pressure chamber to second hydraulic pressure chamber to reduce pressure difference between the first hydraulic pressure chamber and the second hydraulic pressure chamber, and a flow control valve provided in the pressure regulating channel to open and close the pressure regulating channel according to the pressure difference between the first hydraulic pressure chamber and the second hydraulic pressure chamber.

Abstract: Disclosed is driving unit (1) for a brake (100) comprising: a driving device (2); a hydraulic pump (3) driven by said driving device (2); a hydraulic cylinder (5) in fluid communicating with the hydraulic pump (3) and driven by said hydraulic pump (3). The hydraulic pump (5) is operably connected with one piston rod (7) to drive the piston rod (5) to reciprocate, said piston rod (5) is drivingly connected with a braking portion (8) of the brake (100). The driving unit (1) is further provided with a holding device (10) for keeping the braking portion (8) under an operation state. The present invention further discloses a brake (100) having such driving unit (1).

Abstract: A fluid dispensing apparatus having a) a compressed gas or CO2 cartridge controller, b) a hydraulic pressure medium connected to the CO2 cartridge controller, c) a flow control valve connected to the hydraulic pressure medium; and d) a hydraulic piston connected to the hydraulic pressure medium, whereby a CO2 cartridge applies pressure to the hydraulic pressure medium controlled by the CO2 cartridge controller, the flow control valve is operated to precisely meter hydraulic fluid to the hydraulic piston, and the hydraulic piston provides the linear force to dispense a fluid product with similar and matching regulation under pressure. A rotary valve can be provided to use spent CO2 to retract the piston.

Abstract: In a vehicular brake system, an input piston and a pressure piston are coaxially and axially movably supported in a cylinder, and a brake pedal is coupled to the input piston. Pressure chambers formed on the axially opposite sides of the input piston communicate with each other via a communication passage. A control oil pressure can be supplied to a first supply port of the communication passage, and a reaction-force oil pressure can be supplied to a second supply port of a reaction-force chamber of the input piston, while braking oil pressures can be delivered from delivery ports of the respective pressure chambers.

Abstract: Brake installation consisting of a master cylinder associated with a brake booster furnished with a motor driving an actuator piston and acting on the primary piston of the master cylinder by means of a reaction disk against which the piston rests. For a safety operation, the hydraulic actuator connected to the control rod actuated by the brake pedal rests on the rear face of the reaction disk. The actuator piston is combined with an auxiliary piston in order to interact with the reaction disk and it is guided by its sleeve-shaped portion in a bore of the body of the brake booster. An adapting shim is supported by the auxiliary piston in order to receive as a support the end of a rear rod, secured to the primary piston of the master cylinder. The thickness of the assembly formed by the adapting shim and the auxiliary piston is defined on mounting of the master cylinder and of the brake booster as a function of the free travel measured previously.

Abstract: In a vehicular brake system, an input piston and a pressure piston are coaxially and axially movably supported in a cylinder, and a brake pedal is coupled to the input piston. Pressure chambers formed on the axially opposite sides of the input piston communicate with each other via a communication passage. A control oil pressure can be supplied to a first supply port of the communication passage, and a reaction-force oil pressure can be supplied to a second supply port of a reaction-force chamber of the input piston, while braking oil pressures can be delivered from delivery ports of the respective pressure chambers.

Abstract: Disclosed is driving unit (1) for a brake (100) comprising: a driving device (2); a hydraulic pump (3) driven by said driving device (2); a hydraulic cylinder (5) in fluid communicating with the hydraulic pump (3) and driven by said hydraulic pump (3). The hydraulic pump (5) is operably connected with one piston rod (7) to drive the piston rod (5) to reciprocate, said piston rod (5) is drivingly connected with a braking portion (8) of the brake (100). The driving unit (1) is further provided with a holding device (10) for keeping the braking portion (8) under an operation state. The present invention further discloses a brake (100) having such driving unit (1).

Abstract: An actuator assembly (1) comprises a body (2) in which works an actuating piston (7), a first piston (5) and at least one second piston (6), a chamber (26) containing a substantially incompressible fluid by which each of the first and second pistons (5, 6) acts on the actuating piston (7). The movement of the first piston (5) from a retracted position to an extended position acts via the fluid to cause the actuating piston (7) to move from a retracted position to an operational position, and subsequent movement of a second piston (6) from a retracted position to an extended position acts via the fluid to cause an actuation movement of the actuating piston (7).

Abstract: A hydraulic system that allows pressurized fluid to be stolen from a master or lift cylinder and directed to a single acting cylinder to perform a function. The system utilizes a spring in the single acting cylinder to force the fluid to retract through the same single line that powered the single acting cylinder. The fluid is then routed to the unloaded side of the master cylinder. This system provides many cost efficiencies and may be utilized by work vehicles to perform secondary functions such as attaching and removing an implement and locking and unlocking a loader.

Abstract: A hydraulic system maintains squareness while extending an object via two lift cylinder assemblies. A hydraulic circuit is connected to the cylinder assemblies, and includes synchronizer with multiple isolated chambers corresponding to the cylinder assemblies, a rod extending axially through the chambers, and pistons mounted on the rod and associated with the isolated chambers. The hydraulic circuit operably connects a pump to the synchronizer and to the cylinder assemblies for controlling and providing synchronized movement of the cylinder assemblies. The hydraulic circuit includes valving for an automatic re-synchronization cycle, fill cycle, and air purge cycle. The system is effective for moving large objects in a non-binding manner, such as an extendable room on a recreational vehicle, while maintaining accurate squareness.

Abstract: Apparatus for controlling brakes in bicycles and the like, made with a pump connected to a relevant reservoir, characterized in that the reservoir is disposed inside a containment body and exhibits a concave portion shaped complementarily to a handlebar's portion to which the body is to be fixed.

Abstract: A lift table maintains levelness while lifting a support surface via two or more lift cylinder assemblies. A hydraulic circuit is connected to the cylinder assemblies, and includes synchronizer with multiple isolated chambers corresponding to the lift cylinder assemblies, a rod extending axially through the chambers, and pistons mounted on the rod and associated with the isolated chambers. An axial passageway extends continuously through the rod and is connected to first passageways for communicating hydraulic fluid to one side of the chambers. The hydraulic circuit operably connects a pump to the axial passageway of the synchronizer and to second passageways connected to the chambers and to the cylinder assemblies for controlling and providing synchronized movement of the at least two lift cylinder assemblies. The hydraulic circuit includes valving for an automatic re-synchronization cycle, fill cycle, and air purge cycle.

Abstract: A combined master cylinder and dump valve includes a piston slideable within a body bore that defines a master cylinder for pressurizing a brake port. The piston includes a piston seal for isolating a pressure port from a tank port, a piston bore, a first piston hole set for hydraulically connecting the pressure port to the piston bore and a second piston hole set for hydraulically connecting the piston bore to the tank port. A plunger slideably received in the piston bore has a plunger hole set for selectively connecting the first piston hole set with a plunger bore, and a plunger seal arrangement for selectively isolating the first piston hole set from the plunger bore. The plunger bore is hydraulically connected to the piston bore.

Abstract: A device for clamping a rod to stop axial and/or rotative movement between the rod and the device. The device includes pressure and clamp units, the clamp unit having a bushing fixed therein and provided with a radially resilient center section normally sized to permit movement of the rod therein. The pressure unit has an actuating piston normally held under fluid pressure in one position but movable under spring pressure toward a second position should the fluid pressure be lost or released. Such movement results in the application of pressure to the bushing to radially deflect its center section inwardly into clamping engagement with the rod to stop its movement. The center section remains clamped on the rod until sufficient fluid pressure is applied to the actuating piston to move it back to its first position thus permitting radial expansion of the center section to release the rod for movement.

Abstract: A lift table maintains levelness while lifting a support surface via two or more lift cylinder assemblies. A hydraulic circuit is connected to the cylinder assemblies, and includes synchronizer with multiple isolated chambers corresponding to the lift cylinder assemblies, a rod extending axially through the chambers, and pistons mounted on the rod and associated with the isolated chambers. An axial passageway extends continuously through the rod and is connected to first passageways for communicating hydraulic fluid to one side of the chambers. The hydraulic circuit operably connects a pump to the axial passageway of the synchronizer and to second passageways connected to the chambers and to the cylinder assemblies for controlling and providing synchronized movement of the at least two lift cylinder assemblies. The hydraulic circuit includes valving for an automatic re-synchronization cycle, fill cycle, and air purge cycle.

Abstract: A servoactuator (20) is operatively arranged to control the movement of an output member (21) in either of two directions in response to a command signal. The servoactuator includes an electric motor (25); a first transmission mechanism (34); a hydrostatic second transmission mechanism (35); a transfer mechanism (36) operatively arranged to selectively couple the motor output shaft to the output member either through the first transmission mechanism to impart a high-speed low-force drive to the output member, or through the second transmission mechanism to impart a low-speed high-force drive to the output member; at least one feedback transducer (29, 32); and a servo control loop (30, 33) closed about the motor, controller, transmission mechanisms, transfer mechanism, feedback transducer and output member for selectively controlling at least one of the position, velocity or force of the output member as a function of the command signal.

Abstract: A brake booster comprising an envelope (2) having a longitudinal axis (X) formed of a first (4) and of a second (6) shell to define an interior volume divided by moving a skirt into a low-pressure first chamber and a variable-pressure second chamber. A three-way valve (12) actuated by a control rod places the front chamber and the rear chamber in communication at rest and during a braking phase interrupts the communication between the front chamber and the rear chamber and thereafter allows communication of pneumatic fluid at high pressure to the rear chamber. The booster is attached to the master cylinder by a clip-fastening arrangement wherein tabs (52) that radially extend from a sleeve tube (48) are plastically deformable in the radial direction on enter into a passage (54) in a flange (56) of the master cylinder and returning to the initial position when the attachment operation is complete.

Abstract: A servoactuator (20) is operatively arranged to control the movement of an output member (21) in either of two directions in response to a command signal. The servoactuator includes an electric motor (25); a motor controller (24); a first transmission mechanism (34); a hydrostatic second transmission mechanism (35); a transfer mechanism (36) operatively arranged to selectively couple the motor output shaft to the output member either through the first transmission mechanism to impart a high-speed low-force drive to the output member, or through the second transmission mechanism to impart a low-speed high-force drive to the output member; at least one feed-back transducer (29, 32); and a servo control loop (30, 33) closed about the motor, controller, transmission mechanisms, transfer mechanism, feedback transducer and output member for selectively controlling at least one of the position, velocity or force of the output member as a function of the command signal.

Abstract: An improved brake hydraulic pressure generating device is provided in which the hydraulic pressure supplied from a hydraulic pressure source is adjusted to a value corresponding to the brake operating force by means of a pressure adjusting valve which is activated according to displacement of an input piston or a simulator piston, and while the device is normal, a master cylinder is activated by the output hydraulic pressure. If the hydraulic pressure source or a hydraulic line connecting thereto fails, a sufficient braking force is ensured with a short stroke. There are provided a shutoff valve which shuts off communication between the simulator chamber and the atmospheric reservoir when the stroke of the input piston has exceeded a predetermined value, and a check valve which permits the flow of fluid from the atmospheric reservoir to the simulator chamber. This suppresses an unavailable stroke of the simulator piston without impairing the return of the simulator piston.

Abstract: A piston-cylinder mechanism includes a cylinder (50) that defines a cylindrical bore (51). Two pistons (52, 53) are disposed within the cylindrical bore, so that a first pressure chamber (57), a second pressure chamber (58) and a third pressure chamber (59) are defined within the cylindrical bore. The first pressure chamber and one of the second and third pressure chambers individually receive a supply of a pressurized fluid. The pressurized fluid is delivered individually from the second pressure chamber and the third pressure chamber to respective external devices (16, 17). A valve (60; 160) is arranged between one of the second pressure chamber and the third pressure chamber and the corresponding external device. The valve is operable to open and close when the one of the second pressure chamber and the third pressure chamber is expanded and contracted, respectively, due to the movement of the pistons.

Abstract: A fluid operated actuator includes a shaft and a housing. The shaft is at least partially mounted in the housing for relative rotation between the shaft and the housing. The shaft includes a substantially central bore in which a first piston is mounted. The shaft also includes a fluid inlet that is connectable to supply of pressurised fluid and a fluid outlet. A conduit is provided for the flow of fluid between the inlet and the outlet. One end of the housing includes a chamber in which there is mounted a valve assembly comprising a second piston and a valve arranged to selectively open or close an inlet to the chamber. Fluid exiting the outlet opens the valve and exerts a force on the second piston, causing movement thereof in a first direction.

Abstract: The main subject of the present invention is a pneumatic brake booster comprising an envelope (2) of longitudinal axis (X) formed of a first (4) and of a second (6) shell, and defining an interior volume divided by a moving skirt into a low-pressure first chamber and a variable-pressure second chamber, a three-way valve (12) actuated by a control rod and placing the front chamber and the rear chamber in communication at rest and during a braking phase interrupting the communication between the front chamber and the rear chamber and supplying the rear chamber with pneumatic fluid at high pressure, said booster also comprising at least one means (46) for securing a master cylinder to said booster, advantageously two means, characterized in that said means (46) allow the master cylinder to be attached to the booster by clip-fastening.

Abstract: A vehicle hydraulic brake apparatus includes a hydraulic pressure generator which generates a power pressure irrespective of operation of a brake pedal and a regulation valve which regulates the power pressure to a predetermined pressure corresponding to an operation force of the brake pedal and outputs it to an output chamber. A master cylinder generates a master cylinder pressure in a master cylinder chamber by forward movement of the master cylinder piston and a wheel brake cylinder is operated by the master cylinder pressure to apply braking force to a vehicle wheel. An auxiliary piston is located backward the master cylinder piston to define an auxiliary pressure chamber between the master cylinder piston and the auxiliary piston and to move the master cylinder piston forward by an auxiliary pressure in the auxiliary pressure chamber. A pressure modulating device decreases the predetermined pressure outputted from the output chamber to supply the auxiliary pressure to the auxiliary pressure chamber.

Abstract: A vehicle braking system in which an annular piston brake and a booster to generate an amplified output force for actuating the brake are combined to form an integrated unit. The booster is mounted on an axle casing in which the piston brake is located so that the amplified force acts directly on fluid in a chamber to displace the piston brake. A self-bleeding facility for the brake fluid is provided via the booster.

Abstract: A hydraulic intensifier generates a hydraulic pressure which is higher than the input hydraulic pressure generated in the discharge port and the outer periphery hydraulic pressure chamber. The hydraulic intensifier, provided inside a case member, has a discharge part connected with an outer periphery hydraulic pressure chamber. An input port supplies input hydraulic pressure from the exterior to an input oil chamber of hydraulic intensifier. Oil is filled in a sealed manner in outer periphery hydraulic pressure chamber.and discharge part. The hydraulic intensifier is driven by the input hydraulic pressure. The rod is locked by the elastic deformation of a thinned tube part of a sleeve body. A relatively small hydraulic locking device having a relatively high power is achieved. Furthermore, a relatively small hydraulic pressure source having reduced pressure is realized.

Abstract: In a brake booster of the present invention, by depression of a brake pedal 3, an input shaft 4 travels to the left, a pedal input converter generates thrust, and a valve element 5a moves to the left. A valve passage 5a1 is shut off from a valve passage 5b1 and a valve passage 5a2 is connected to a valve passage 5b2 so as to develop output pressure Pr at an output port 5c of a control valve 5 because of the pressure of a pressure source. The output pressure Pr is supplied to a wheel cylinder 7, thereby actuating the brake. At this point, since the displacement of the input shaft 4 required for operating the control valve 5 is defined only by the converter 6, the input side is not affected by the brake rigidity of a circuit from the control valve 5 to the wheel cylinder 7. The output pressure Pr of the control valve 5 acts on the valve element 5a through a first reaction receiving portion 8 and is regulated to pressure proportional to the thrust of the converter 6.

Abstract: A hydraulic pressure brake device is provided with a vacuum boosting device performing a boosting operation and a hydraulic boosting device performing a hydraulic boosting operation. The hydraulic pressure brake device includes a valve device that prohibits the hydraulic boosting operation for the master cylinder piston by the hydraulic boosting device until the vacuum boosting device reaches its boosting limit and allows the hydraulic boosting operation for the master cylinder piston by the hydraulic boosting device when the vacuum boosting device exceeds its boosting limit. A detecting sensor detects the operational condition of the vacuum boosting device and/or the operational condition of the brake pedal. Based on the detected output by the detecting sensor, a pump device for supplying the boosting pressure by the hydraulic boosting device is controlled to be driven.

Abstract: The fluid-pressure ram, for controlling a clutch release bearing for an automobile clutch, has two variable-volume control chambers which follow each other axially and comprise a primary chamber which is fed with pressurized fluid and which is axially delimited sealingly, to the front by a fixed base and to the rear by a movable wall integral with a shell, and a secondary chamber which is axially delimited sealingly, to the front by the movable wall and to the rear by the piston, the movements of the fluidtight movable wall bringing about a decantation of a fluid contained in an intermediate chamber to the secondary chamber, and vice versa, the said shell separating the intermediate chamber from the secondary chamber.

Abstract: The invention relates to a hydraulic pressure transformer, wherein a storage chamber and a work chamber are connected with each other via an overflow bore into which a plunger piston dips to generate a pressure stage and thereby separates the two chambers for generating a high pressure in the work chamber. An additional connecting conduit with a check valve is provided between the work chamber and the storage chamber.

Abstract: The combined pneumatic-hydraulic press head includes a body inside which a substantially cylindrical main chamber is defined; the chamber accommodates a main piston and a secondary piston so that they can slide along an axial direction. The main piston has a stem which protrudes from an axial end of the main chamber, and the secondary piston is spaced from the main piston on the side opposite to the stem. The two pistons sealingly divide the main chamber into three chambers: two end chambers, which can be connected to a source of compressed air or to the atmosphere in order to move the two pistons along the axis of the main chamber during the approach of the main stem or spacing motion with respect to the part to be treated, and an intermediate chamber which contains a liquid. An actuation stem is furthermore accommodated in the main chamber and sealingly passes through the secondary piston.

Abstract: The combined pneumatic-hydraulic press with controlled stroke, includes a body inside which a substantially cylindrical main chamber is defined; the main chamber accommodates, so that it can slide along an axial direction, a working piston which protrudes from the body with its stem. The working piston delimits, in the main chamber, a first compartment which contains a liquid and is connected, through a passage, to a secondary chamber which is provided with elements for exerting pressure on the liquid contained in the secondary chamber in order to transfer at least part of the liquid from the secondary chamber to the first compartment in order to axially move the working piston.

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: The hydraulic cylinder comprises a cylinder jacket (1), a piston-rod guide flange (2), and a cylinder bottom (3). Disposed within the cylinder are a primary piston (4) provided with a piston rod (6) and a secondary piston (11) connected to two plungers (7, 8). The plungers enter two bores (5, 6) in the primary piston. Two spring-biased (19, 20), openable check valves (17, 18) are disposed in the cylinder bottom. In each valve there is a bore (41, 42) connecting the front and rear sides of the valve. The rear portions (24, 25) of the valve chambers (26, 27) each contain a spherical unstopping piston (21, 22). Two supply ducts (23, 30) for the hydraulic fluid are connected to the valve chambers, these chambers in turn having supply ducts at various locations (36, 40, 45) of the interior of the cylinder. A very compact construction is possible for the hydraulic cylinder with pressure transmission.

Abstract: An improvement of a liquid pressure booster provided with a reaction piston is disclosed. A guide formed on a housing (plug) is caused to project into a tubular section of a power piston. A reaction piston is slidably supported by the guide, and an input shaft is slidably supported by the reaction piston. A spring which urges the reaction piston is disposed in a clearance defined between the outer periphery of the guide and the inner periphery of the tubular section of the power piston. In this manner, the guide, a sliding portion of the reaction piston, a sliding portion of the input shaft and the spring can be disposed radially of each other while overlapping each other in the axial direction to minimize the axial size of the liquid pressure booster.

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: A hydraulic actuator is formed by a first element incorporating a plurality of different sized piston cavities by a first set of piston elements which cooperate with a second set of piston elements and piston cavities respectively formed on a second element. Each of the cavities is selectively connected to a source of high pressure fluid or a source of low pressure fluid. The second element forms a driven piston in a cylinder formed by an extension of the first element. A second cylinder of a cross sectional area different from the first cylinder is hydrulically connected to the first cylinder and incorporates a second piston at its end remote from the first piston. The force or distance travelled by the second piston is correlated with that of the first or driven piston in a ratio equal to the ratio of the cross sectional areas of the two pistons. Preferably the second piston will be a double acting piston so that pressure may be applied to force the driven piston and first element together.

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: The invention relates to a braking device for a motor vehicle having a bulkhead (1) separating the passenger compartment (5) from the engine compartment (3). The device comprises a master cylinder (7) having a flange (13), via which it is fastened by means of a screw/nut assembly (15) to the front wall of a pneumatic brake booster (9) controlled as a result of the action on a tappet (11) passing through the rear wall of a brake booster, and a mechanism for fastening the device to the bulkhead (1) such that the brake booster (9) is arranged on the same side as the passenger compartment (5). The master cylinder (7) is partially arranged in the passenger compartment (5) and passes through an opening made in the bulkhead (1) for this purpose.

Abstract: A pneumatic piston/cylinder unit comprises primary and secondary pistons operable in first and second cylinder zones respectively. Each of the primary and secondary pistons divide its respective cylinder zone into two chambers, one of the chambers of the first cylinder zone being connected to one of the chambers of the second cylinder zone via a passageway which includes at least one control for the flow of hydraulic fluid therethrough. A tertiary piston is provided in the one chamber of the first cylinder zone and divides that chamber into two parts, one of which is between the primary and tertiary pistons. In use the passageway, the one chamber of the second cylinder zone and the other part of the one chamber of the first cylinder zone are filled with hydraulic fluid. Application of pneumatic pressure to the other chamber of the first cylinder zone causes the primary piston to be displaced until it abuts the tertiary piston whereupon movement of the primary piston may be arrested or controlled.

Abstract: In a brake booster, a master brake cylinder is connected to a brake pedal via a piston rod, which acts upon a master cylinder piston by way of which at least one brake chamber can be put at brake pressure. In this way, servo fluid flows via brake lines to corresponding wheel brake cylinder is a servo chamber, which via a control element communicates with a device for supplying servo fluid to the servo chamber. This control element is controlled via a travel transducer that detects the motion of the piston rod. A lever arrangement is also connected to the piston rod, and on its other end is operatively connected to the travel transducer, which triggers the control element via an electronic unit to maintain the servo pressure.

Abstract: An apparatus is provided for connecting a master cylinder to a brake booster of the type which has a shell with a planar front surface and a plurality of threaded studs displayed about the bore and projecting from the planar front surface. The master cyliner has a necked down end portion defining a shoulder facing the booster. The master cylinder has a circumferential extending groove provided in the necked down end portion and spaced longitudinally from the shoulder. An adapter has a central aperture to receive the necked down end portion of the master cylinder and a plurality of apertures which register with the plurality of threaded studs. A lock ring or other locking device is received in the groove of the master cylinder and effective to lock the adapter to the master cylinder and in engagement with the shoulder. A plurality of threaded nuts are installed on the threaded studs to retain the adapter in engagement with the planar surface of the booster shell.

Abstract: In a brake system having an auxiliary, booster or slave cylinder, the addition of a middle chamber between the forward and rear chambers of the master cylinder to increase the unit pressure (psi) and insure sufficient fluid volume to prevent failure of the system.

Abstract: The brake pressure generator (1) includes a tandem master cylinder (2) actuable by two booster pistons (19, 32) to which a hydraulic auxiliary pressure is applied and by a pedal actuating mechanism (17,18). A control valve (14, 20) controls the auxiliary boost pressure. The control valve, through an actuator (16), cooperates with the pedal actuating mechanism (17,18). One booster piston (32) is disposed on the bottom of the tandem master cylinder (2) adjacent the push rod (22). Normally-open valve (37) closes when brake pressure exceeds boost pressure to trap fluid in chamber (34).

Abstract: A modular brake actuator useful in automotove vehicles includes a mounting base adapted to fit into a complementary opening in and form part of the fire wall between the engine compartment and the driver's cockpit. On one side of the mounting base there are assembled brake operating components and on the other side there are assembled hydraulic components. This module can be easily installed during assembly of the vehicle.

Abstract: A fastener driving tool for driving remotely located fasteners through preformed openings in a structure. The tool (10) comprises a housing (12) having a pneumatic-hydraulic intensifier (14) mounted thereon and a remotely located second hydraulic cylinder assembly (20) attached to the housing (12) by means of an extension tube (110). Pressurized air is provided to the tool (10) through a cartridge regulator (36) that is controlled by a trigger assembly (41). A pneumatic piston (72), connected to a first hydraulic piston (76) by a piston rod (80), moves from a first position located away from a nose portion (66) to a second position located toward a nose portion (66). The pressurizing valve (56) admits air to the pneumatic piston (72) to cause the first hydraulic piston (76) to move to the second position, thereby pressurizing hydraulic fluid (92) and causing the second hydraulic piston (102) to extend from the second cylinder housing (104).

Abstract: A tandem master cylinder with a booster used for a hydraulic actuator such as an automotive brake system. The master cylinder has a first and a second independently movable presser piston disposed in tandem in a first housing such that the presser pistons and the first housing define a first and a second pressure chamber. The booster has a first power piston advanced by a fluid pressure in a first power chamber formed in a second housing, to advance the first presser piston. The booster has a valve operable due to a relative movement between the first power piston, and an operating member for operating said booster, whereby the fluid pressure in the first power chamber is controlled according to an operating force applied to the operating member.

Abstract: An engine or heat pump for a refrigeration system employing a first elongated expansion-compression device defining a pair of chambers, each having a linearly movable piston therein which are axially interconnected by a hollow cylinder. A second expansion-compression device is mounted within the cylinder. Conduit means are provided, one extending into each end of the first device, through the associated piston and into the cylinder. The first device forces working fluid received through the device to provide fluid under relatively high pressure to the power and work loops of a refrigeration system, while the second device actuated by the first device draws relatively low pressure fluid from the system and returns it under pressure to a source.