Abstract: An aircraft actuation system is disclosed that includes a pair of cylinders, a piston movably disposed in each cylinder, and a roller train that extends between the pistons in the two cylinders. A portion of the roller train is disposed beyond the cylinders to engage a pinion. Movement of the pistons in the two cylinders in opposite directions produces a corresponding movement of the roller train to in turn rotate the pinion. The roller train may be maintained in compression between its two ends by fluid pressure exerted on a common face of each of the pistons in the two cylinders. The cylinders may be disposed in non-colinear relation, including in parallel relation to one another. A guide may be used to maintain rollers of the roller train in a proper orientation for entry into a space between an outer race and the pinion.

Abstract: Fluid refining systems and methods are disclosed. A fluid refining apparatus may include an upper motor connected to an upper housing, and a lower motor connected to a lower housing. A central housing may be connected between the upper and lower housing. An upper shaft may be connected to the upper motor and rotatably disposed within the upper housing. A lower shaft may be connected to the lower motor and rotatably disposed within the lower housing. A group of nested upper cylinders may be connected to the upper shaft. A group of nested lower cylinders may be connected to the lower shaft. The group of nested upper cylinders may be positioned adjacent the group of nested lower cylinders in an interlacing, fingerlike relationship, and disposed for counter rotation relative to one other. Each of the cylinders may include flow apertures adapted for cooperative relationship to establish fluid flow paths.

Abstract: A construction machine according to an exemplary embodiment of the present invention includes: an engine; a boom cylinder which is divided into a head side and a rod side; a regeneration line through which hydraulic fluid discharged from the head side of the boom cylinder moves when the boom descends; a regeneration motor which is connected with the regeneration line and is operated, and assists the engine; a pilot pump which generates a pilot pressure; a pilot line through which pilot hydraulic fluid discharged from the pilot pump moves; a regeneration connection line which connects the pilot line and the regeneration line; an on/off valve installed in the regeneration connection line; and a control device which closes the on/off valve when a pressure of the pilot line drops below a predetermined pressure or the hydraulic fluid discharged from the boom cylinder is supplied to the regeneration motor.

Abstract: An actuation system for controlling flight control members of a vehicle. Each flight control member is controlled by two or more linear hydraulic actuators. Synchronization members extend between the hydraulic actuators on the same flight control members to synchronize the movements of the hydraulic actuators for consistent movement across the length of the flight control members. Brakes can maintain the positions of the synchronization members and thus the flight control members. Motors can provide for moving the synchronization members to control the positioning of the hydraulic actuators and flight control members.

Abstract: A device for changing a blade on shears, in particular for a rolled band, and to such shears in which a blade can be fixed to at least one blade support automatically by a tie bar pretensioned by a force accumulator. The device includes at least one adjusting element which can be actuated in order to release the blade from the blade support such that the tie rod is moved in an axial direction against the tie rod pretension. The adjusting element can be arranged on an outer face of the blade support or outside of the blade support.

Abstract: An energy recovery system for a machine is disclosed. The energy recovery system may have a pump configured to provide a flow of pressurized fluid. The energy recovery system may also have a first fluid actuator with a first chamber and a second chamber and being configured to receive the pressurized fluid, a second fluid actuator with a third chamber and a fourth chamber and being configured to receive the pressurized fluid, and a first valve fluidly connected between the pump and the first and second actuators. The energy recovery system may additionally include an isolation unit with a first selectively restrictable passageway fluidly connecting the first chamber, the third chamber, and a first outlet of the first valve, and a second selectively restrictable passageway fluidly connecting the second chamber, the fourth chamber, and a second outlet of the first valve, as well as an energy recovery unit in fluid communication with the isolation unit.

Abstract: A hydraulic blowout preventer operator comprises a first piston rod coupled to a closure member. The operator further comprises a first operator housing coupled to a bonnet and a head. The first piston rod extends through the bonnet into the first operator housing where is couples to a first piston disposed within the first operator housing. The operator further comprises a second piston rod coupled to the closure member. The second piston rod has a longitudinal axis that is parallel to a longitudinal axis of the first piston rod. The second piston rod extends through the bonnet into a second operator housing and is coupled to a second piston that is disposed within the second operator housing.

Abstract: A multistage mast assembly for use on a lift truck and method of operation for staging first and second mast sections of the multistage mast assembly. Each mast section has a retracted position and an extended position. The apparatus includes a mast staging hydraulic circuit which diverts hydraulic fluid from the second mast section actuator to the first mast section actuator using a multi-position valve having an open position and a restricted flow position. In the restricted flow position, hydraulic pressure in a hydraulic line supplying the second mast section increases to divert hydraulic fluid to the first mast section actuator before the second mast section reaches its extended position.

Abstract: A pair of hydraulic cylinders 10 which are coupled to a driven member, placed parallel to each other and extend/contract in synchronization with each other, and a control valve 20 which controls hydraulic fluid supplied to or discharged from the hydraulic cylinder 10 are provided. An elastic support mechanism 50 which supports the control valve 20 to each hydraulic cylinder between the paired hydraulic cylinders 10; metallic piping 30 and the metallic piping 40 which connect the control valve 20 with the respective hydraulic cylinders 10 and leads the hydraulic fluid controlled by the controlling valve 20; and curved portions 31c, 32, 41c, 42a which are provided at some midpoints of the piping and flexibly deform in accordance with relative deformation of each hydraulic cylinder 10 are provided. A difference in relative displacement of each hydraulic cylinder with respect to the control valve 20 is absorbed by deformation produced in the elastic support mechanism 50 and the curved portions.

Abstract: A power steering assembly and method of retrofitting therefore includes a housing having a cavity defined therein. A drive member extends axially into the cavity and a first piston and a second piston are received in the cavity for axial reciprocation therein. The first and second pistons define at least in part first and second pairs of chambers. The first pair of chambers receive fluid under pressure to move the first and second pistons toward one end of the housing to rotate the driven shaft in a first direction. The second pair of chambers receive fluid under pressure to move the first and second pistons toward the other end of the housing to rotate the driven shaft in a second direction opposite the first direction.

Abstract: The knuckle boom includes a hoist boom having a proximal end pivoted to a machine base, and a stick boom having a proximal end pivoted to a distal end of the hoist boom. At least one hydraulic hoist cylinder is mounted between the machine base and the hoist boom, and at least one hydraulic stick cylinder is mounted between the hoist boom and the stick boom. A hydraulic circuit supplies hydraulic oil to the cylinders, and provides an oil flow path between working ends of the cylinders so as to transfer a slug of pressurized hydraulic oil between the working ends. In one embodiment, reaching movement is controlled by a pump connected to control transferring of the slug between the hoist and stick cylinders. The pump determines which cylinder receives which portion of the slug of oil, and thereby controls the angle between the booms, thereby producing reach.

Abstract: A system for simultaneously operating first and second hydraulic cylinders has an inlet node for connection to a source of pressurized fluid and an outlet node for connection to a tank. A two-position, three-way primary control valve has a first port connected to the inlet node, a second port connected to the outlet node, and a common port. A first electrohydraulic proportional valve connects the common port to a first port of the first cylinder, and a second electrohydraulic proportional valve connects the common port to a first port of the second cylinder. A third electrohydraulic proportional valve connects the inlet node to a second port of the first cylinder and a second port of the second cylinder. Selectively operating the primary control valve and one of the third and fourth electrohydraulic proportional valves determines the direction in which the first and second cylinders move.

Abstract: An integral valve-cylinder assembly and a fork folding hydraulic system for front loading waste collection vehicles is provided that allows the forks to be full tucked for over-the-road travel and without exceeding the vehicle height limit that uses a multi-port hydraulic cylinder integrated with a remotely activated valve that is operated with a single control valve from within the vehicle cab.

Abstract: The invention provides a method and apparatus for controlling in a path-dependent manner the force generated by a piston. A first piston travels in a first cylinder—divided into a first and second chamber by the first piston—together with a pressure fluid. A second cylinder is provided in which a second piston travels. Like the first cylinder, the second cylinder is also divided by the second piston into a first and a second chamber, in this case by the second piston. The first and second pistons are coupled mechanically. The pressure in the second chamber of the second cylinder is regulated such that it is always equal to the counterpressure in the first chamber of the second cylinder and the second chamber of the first cylinder.

Abstract: A tandem pneumatic booster having a shell body, the inside of which is divided into two, front and rear, chambers by a center shell. Each chamber includes a negative pressure chamber and a working pressure chamber. A valve body is slidably fitted in the shell body and the center shell with seal members therebetween. The valve body is provided with an air passage for communication between the front and rear working pressure chambers. A valve mechanism is actuated in association with an input shaft to introduce atmospheric air into the front and rear working pressure chambers through the air passage so as to apply thrust to front and rear power pistons. The diaphragm of the front power piston has a bead on an inner periphery thereof. The valve body has a groove on an outer periphery thereof. A portion of the air passage which leads to the front working pressure chamber has a main passage portion extending axially in the valve body, and a bypass extending radially outward from the main passage portion.

Abstract: A removable side shifter attachment attachable to the carriage bar of a lift truck has a frame shiftable with respect to the truck. The frame includes a shifter carriage bar for receiving a lift fork. A hydraulic cylinder attached to the truck carriage bar having rods contacting the frame at its sides is positioned horizontally forwardly of the truck carriage bar and between the truck carriage bar and the shifter carriage bar. The cylinder is positioned generally within a J-shaped portion of the shifter carriage bar so that the cylinder does not extend substantially above or below the carriage bar and does not appreciable add to the overall thickness of the apparatus. The cylinder further includes two axially aligned chambers separated by a central partition, each chamber containing a piston in contact with a respective rod, each piston dividing its respective chamber into interior and exterior portions.

Abstract: To prevent a rolling diaphragm (13), which forms the movable wall (4) of a vacuum brake booster along with a metallic diaphragm disk (12), from becoming detached from an annular groove (52) accommodating a radially inner bead (32) of the rolling diaphragm (13), the rolling diaphragm is connected to the edge of the bead (32) located away from the (first) diaphragm disk (12). By connecting the rolling diaphragm (13) to the edge of the bead (32) located away from the (first) diaphragm disk (12), a pneumatic space (27) is defined by the rolling diaphragm (13) and the (first) diaphragm disk (12). Pressure occurring in the vacuum chamber(s) (28, 30) can be admitted to the pneumatic space (27).

Abstract: A tandem vacuum booster includes a front shell and a rear shell which are connected to each other to form a housing, a front movable wall having an outer circumferential portion that is fit in a fluid-tight manner between the front shell and the rear shell, and a rear movable wall having an outer circumferential portion that is fixed to the rear shell. A fixed wall has an outer circumferential portion that is fit between the front movable wall and the rear shell, with the fixed wall including a bent portion which presses the outer circumferential portion of the rear movable wall to the rear shell.

Abstract: A guide rod extends longitudinally through the power piston of a vacuum power booster providing lateral support thereto and tying the master cylinder housing to a bracket on the rear of the power booster housing. A guide rod provides a means of positively laterally supporting the power piston, control valve and push rods of the power booster thereby providing the ability to reduce the relative supportive strength of the housing, housing divider and piston bearings.

Abstract: A multi-piston assembly is illustrated wherein a cylindrical housing (A) is ported through longitudinal circumferentially spaced ports (F) and (G) carried within the cylindrical housing. Porting through piston rods is thus avoided so that their cross section may be reduced thereby increasing the area of the pistons available for contact by pressurized fluid. Even greater force may be made available for actuating a tool by the addition of an add-on unit utilizing complementary longitudinal porting.

Abstract: An improvement of the inner periphery of a power piston which is connected to a valve body of a booster is disclosed. The inner periphery of the power piston comprises a radial portion which is disposed in abutment against an end face of a step formed on the valve body, an annular groove located radially outward of the radial portion, and a step formed at the boundary between the radial portion and the annular groove. The provision of the annular groove and the step assures sufficient strength around the inner periphery of the power piston without requiring an increased wall thickness of the power piston.

Abstract: A method of manufacturing a tandem brake booster by selectively choosing a front shell having a first cylindrical body with first effective diameter, a transition shell having a second cylindrical body with a second effective diameter and a rear shell having a third cylindrical body with a third effective diameter. The cylindrical body of the transition shell is an integral component of an end wall which separates the interior the resulting tandem brake booster. The end wall has a peripheral ledge with a flange extending therefrom and a groove located on the flange connected to the second cylindrical body. An annular surface on the first cylindrical body is crimped into the groove on the flange while a corresponding annular surface on the second cylindrical body is crimped onto the third cylindrical to join the transition shell with the rear shell to form an integral unit.

Abstract: A hydraulic drive passenger lift with distinct lifting "up and down" (loading, unloading) and "fold-unfold" (storage) motion patterns, includes a flow control structure that accommodates various hydraulic flows, somewhat unrestricted for "up-and-down" movement, and different for "fold" and "unfold" movements. The flow control structure includes multiple paths between a source and an actuator, with control for selecting the appropriate path to yield predetermined flow rates. A solenoid driven spool valve and a biased movable orifice member select the desired path. Accordingly, while the flow is substantially unrestricted during "up-and-down" movement, it is somewhat restricted for reduced speed during the "unfold" movement and is more restricted during the power-driven "fold" movement.

Abstract: The present invention discloses an actuating unit that achieves shortening of the actuating travel of the brake power booster when the brake system is precharged. The actuating unit is preferably used with hydraulic brake systems of automotive vehicles having a master brake cylinder and a pneumatic brake power booster connected upstream thereof. The master brake cylinder is integrated in the booster housing of the brake power booster and a control valve of the brake power booster is arranged laterally beside the master brake cylinder. The control valve operates opposite to the actuating direction of the actuating member actuating the brake power booster by means of a lever mechanism with variable transmission. The lever mechanism is adapted to be deactivated in terms of effect after a predefinable actuating stroke of the master brake cylinder.

Abstract: In a tandem type vacuum booster, the inner peripheral end of a front booster piston and the inner peripheral bead of a front diaphragm are clamped between a front end of a sleeve fitted over the outer periphery of a piston boss and a flange provided on the piston boss and are thereby fixed to a front portion of the piston boss, while the inner peripheral end of a rear booster piston and the inner peripheral bead of a rear diaphragm are clamped between a stopper member mounted on the piston boss and a rear end of the sleeve and are thereby fixed to a rear portion of the piston boss. A first port for communicating the front and rear working chambers with the control valve, and a second port for communicating the front and rear vacuum chambers with the control valve extend through both the piston boss and the sleeve, and communication between both the ports is inhibited by a single annular sealing member mounted at an axially intermediate portion of a junction surface between the piston boss and the sleeve.

Abstract: A method of manufacturing a tandem brake booster wherein a rearwall is derived from the separation plate of a single brake booster. The separation plate is modified by creating a passageway therethrough and using splines on the hub which are mated with keyways in a cylindrical body that extends from a front movable wall to assure that passages between the resulting front and rear chambers are aligned. A return spring holds a seal between the cylindrical body and hub to assure cross communication does not occur between the passageways. Thereafter, any operational pressure differential created during a brake application is directed into the development of an output force to effect a brake application.

Abstract: The invention relates to a vacuum brake-booster of the tandem type comprising two compartments (22, 24) separated by a stationary plate (20), each of the compartments being divided into a front chamber and a rear chamber by way of a piston (26, 28) and of an isolating diaphragm, at least the inner edge of which is equipped with a bead (38), each of the pistons (26, 28) being fixed to a movable hub (42) containing a valve mechanism, the piston (26) of the front compartment being so fixed by way of a cylindrical sleeve (30). According to the invention, the hub (42) possesses, on its periphery, a groove (32) into which penetrate respectively the inner end (34) of the piston (28) of the rear compartment (24) and the rear end (26) of the cylindrical sleeve (30), the bead (38) of the inner edge of the diaphragm (40) of the rear compartment (24) ensuring the locking of the assembly as a whole.

Abstract: A negative brake booster having a power piston 8 with a piston unit 8a extending in a radial direction, a cylinder unit 8b provided at a backward position in an axial direction and airtightly and slidably supported on a center plate 4. A front diaphragm 12 is provided between the outer peripheral edge of the piston unit 8a and the front shell 2. A rear power piston with a piston unit 9a extending in a radial direction and a cylinder unit 9b furnished at a backward position in an axial direction, and a rear diaphragm 12 are provided between the outer peripheral edge of the piston unit 9a and the front shell. Further, the rear power piston 9 is connected with the valve body 7 where the flange unit 8c of the front power piston 8 is squeezed between the stepped portion of the outer periphery of the valve body 7 by the rear power piston 9.

Abstract: A pneumatic booster for use, for example, in a brake system of a vehicle, and designed so that the overall axial length is reduced without interfering with the operation thereof. The booster comprises a valve body which is movable back and forth between first and second positions in a housing that is divided by a diaphragm with a power piston into front and rear chambers communicated with respective pressure sources, a valve which allows at least one of the front and rear chambers to selectively communicate with the pressure sources which differ from each other in the level of pressure, and a guide which slidably fits on the outer periphery of the valve body. The valve body has a passage one end of which opens on the outer periphery thereof to connect one of the front and rear chambers to the associated pressure source, the opening of the passage being positioned in the axial direction of the valve body so that the guide overlaps the opening when the valve body is at either the first or second position.

Abstract: An improvement of a variable pressure passage which is formed in a valve body of a booster, for example, a brake booster, is disclosed. The valve body which is disposed within a shell of the booster comprises a first and a second tubular member which are connected together. An axial space is defined by the outer peripheral surface of the first tubular member and the inner peripheral surface of the second tubular member when they are integrally connected together, and forms a variable pressure passage providing a communication between forwardly and rearwardly located, variable pressure chambers. This avoids the formation of an axial bore and a radial opening which are formed in a solid portion of a single member valve body, as occurs in the prior art, thus allowing the mechanical strength of the valve body to be improved.

Abstract: A peripheral sealed interlock for a dual diaphragm tandem vacuum booster with front and rear housings is provided. An outer radial peripheral end of a divider of the inventive interlock is greatly simplified and in the preferred embodiment a bead of a secondary diaphragm is allowed to seal on a rear housing member as well as with the periphery of the divider. The interlock provides a simplified design allowing independent compression of primary and secondary diaphragm beads while at the same time providing an interlock which require lower compression for assembly and sealing.

Abstract: A brake booster includes a center plate disposed within a shell. A seal member is provided to interrupt a communication between a variable and a constant pressure chamber which are located across the center plate. The seal member is formed with a lip, acting as a check valve which releases to the variale pressure chamber any pressure developed in the constant pressure chamber which is to be sealed by the seal member and which rises above the pressure in the variable pressure chamber.

Abstract: An improvement relating to a front shell of a brake booster and a reinforcing plate which is connected to and extends along the inner surface of the front shell is disclosed. A radially inward portion of the front shell is formed with a cylindrical section which extends rearwardly, and an end face which provides a mounting surface for a master cylinder is defined adjacent to the rear end of the cylindrical section. The reinforcing plate is formed with a cylindrical portion which is fitted around the cylindrical section of the front shell, and an end face which is disposed in overlapping relationship with the end face of the front shell. This allows the rigidity of the front shell to be increased without requiring the welding of the reinforcing plate to the front shell.

Abstract: A pneumatic booster comprising a housing, a power piston separating the inside of the housing into a constant pressure chamber and a variable pressure chamber, a valve body attached to the power piston, an output shaft, a plunger slidably received in a bore in the valve body, an input shaft and a valve mechanism in the bore for selectively communicating the variable pressure chamber with a negative pressure source or the atmospheric pressure, the valve mechanism including a valve member mounted on the inner wall of the bore, a first valve seat formed on the inner wall of the bore and a second valve seat formed on the plunger.

Abstract: The variable speed hydraulic unit has the peculiarity of comprising a fixed body and a rotatable body with hydraulic actuation and fixed displacement, which are operatively interconnected. The output shaft of the fixed body is rigidly associated with the input of the rotatable body in turn operatively associated with a terminal output shaft. A flow divider is furthermore provided for dividing the flow of working fluid fed at a constant flow-rate, having its deliveries connected respectively to the fixed body and to the rotatable body, the percentual distribution between the deliveries determining the direction and speed of rotation of the terminal output shaft.

Abstract: A full free lift mast assembly having a first pair of spaced apart uprights, a second pair of spaced apart uprights mounted on the first pair of uprights and elevationally movable therealong and a carriage mounted on the second pair of uprights is provided. A first mast lift jack is connected between the first and second pairs of spaced apart uprights, and first and second interconnected carriage lift jacks are pivotally connected to and between the second pair of spaced apart uprights and the carriage. A first connecting arrangement connects a cylinder of the first and second carriage lift jacks and maintains the first and second carriage lift jacks parallel, in a preselected overlapping relationship relative to each other. Therefore, bending of the carriage lift jacks, fluid leakage, missequencing and the like have been substantially reduced. The full free lift mast assembly is particularly suited for use on a material handling vehicle.

Abstract: A fluid-powered actuator having a body with first and second end walls, with a bulkhead positioned therebetween, which is adjustably rotatable to angularly position the bulkhead relative to the body for fluid-powered operation to establish the end limits of rotation of an output shaft. The actuator has first and second piston heads disposed in the body on opposite sides of the bulkhead to define four fluid-tight chambers. In the preferred embodiment, the bulkhead is selectively clamped between two sidewall portions. A sleeve extends between and fixedly connects the piston heads together. A plurality of guide rods are fixedly attached to and extend between the piston heads and through apertures in the bulkhead in one embodiment, and between the first piston head and the bulkhead and through apertures in the first piston head in another embodiment to transmit torque to the body and through the bulkhead.

Abstract: This invention relates to a fail-safe or auto-return actuator cylinder employing the air spring effect provided by compressed air trapped in an air-spring compartment; which air spring effect replaces the conventional mechanical coil spring employed in conventional fail safe or auto-return air cylinders. The air spring chamber integrally built into the cylinder body is connected to the compressed air supply tube through a check valve that provides the self-charging and self-recharging feature for the air-spring chamber and, consequently, the air-spring chamber remains fully charged with compressed air even when there is a compressed air leak from the air-spring chamber. The air-spring compartment stays charged or becomes automatically recharged even when there is a leak from the air-spring compartment as long as there is compressed air to actuate the cylinder.

Abstract: A cylinder valve includes a body with a threaded extension defining a first output port which screws directly into the cylinder port. An input port connected to a source of hydraulic fluid communicates with the first output port through an axially extending passage in a cylindrical valve spool. The passage also communicates with a second output port axially aligned with the first port and connected through a hose to a second cylinder which operates in unison with the first cylinder. A handle is provided for rotating the spool ninety degrees to block the ports and lock the cylinders against movement. The valve is particularly useful for locking the basket lift cylinders on a cotton harvester in the raised position for maintenance work.

Abstract: The mechanism comprises two movable cylinders (7, 9) which are sealingly slidably mounted on respective stationary pistons which are firmly carried by rods (3, 4) mounted in a stationary casing (1). One of the cylinders (9) supports a rack (11) which meshes with a control pinion (12) and which is centrally connected to the other cylinder (7) and to output members (21) which are intended to be connected to a linkage for the steerable wheels and which pass through an opening (22) formed in a lateral wall of the casing (1).

Abstract: An improved right angle drill including a pneumatically powered motor and feed and retract apparatus driven by the motor. The feed and retract apparatus includes a control valve for controlling the flow of pressurized air to the motor and to the feed and retract apparatus to automatically stop the feed motion, to automatically stop the retract motion, and to stop the drill completely.

Abstract: A tandem diaphragm brake booster includes a housing, first and second diaphragms disposed in said housing, a partition wall disposed between said first and second diaphragms within said housing for defining four pressure chambers. The housing is composed of a cup-shaped shell section having a broad cylindrical outer wall and a flange shaped rear shell section. A bead of the first diaphragm is situated between the inner surface of the front sell section and a securing member of the partition wall for defining the first and second chambers. The second diaphragm has inner and outer beads and through-holes at its periphery. The inner bead is compressed between the peripheral edge of the partition wall and the inner surface of the rear shell section and the outer bead is air-tightly secured between both peripheral edges of the front shell section and rear shell section.

Abstract: A petroleum pumping unit which is especially suitable for use in remote oil fields and under unpredictable pumping conditions is disclosed. The petroleum pumping unit of the present invention, which is easily movable between a folded, collapsed position for storage and shipment and an erect position for pumping operations, includes a horizontal support platform on which is pivotally mounted a mast assembly including a pair of masts spaced outwardly from the centrally positioned well polish rod. The polish rod is engaged by a notch in a horizontal, vertically movable bridle and is powered by at least one pair of flexibly mounted hydraulic cylinders and associated piston rods attached to the bridle and positioned between the polish rod and the masts and parallel thereto. Vertical movement of the bridle and, therefore, the stroke of the polish rod is defined by upper and lower limit switches which are actuated by actuating means on the bridle.

Abstract: In a servo booster for a vehicle braking system, of the kind having a tie rod for relieving the booster housing of braking reaction forces which extends through the movable wall(s) of the booster, the movable wall is sealingly connected to a wall of the housing by a bellows located substantially coaxially about the tie rod. The bellows has at least one integral reinforcing rib which completely encircles the tie rod. The rib resists ballooning of the bellows and also guides the bellows along the tie rod. In the case of a tandem booster having a stationary partition wall between a pair of movable walls, the interior of a bellows connecting the rear movable wall to the partition wall provides fluid communication between the chambers bounded by the rears of the movable walls. Fluid communication between the other two chambers is provided via a tubular member integral with the front movable wall and extending sealingly through the partition wall.

Abstract: A valve, comprising: a cylindrical casing, closed at its ends by covers, and having axially aligned inlet and outlet chambers midway of its length disposed at right angles to the axis of the casing. Communication between said chambers is controlled by a ported, fluid pressure operated, movable valve plate assembly, including parallel cylinders, each containing a stationary piston connected to the inner end of a pair of axially aligned rods, or guides, fixed at their outer end to the covers. Each rod has a passageway communicating at its inner end with one end of its associated cylinder for supplying operating fluid thereto to bodily reciprocate the valve plate assembly on said rods within the casing. An adjustable collar positions a fixed wear plate in sealing engagement with one side of the valve plate assembly, and a fluid pressure actuated loading ring urges a floating wear plate into contact with the other side of said valve plate assembly.

Abstract: The brake booster comprises two booster units in a tandem arrangement each having a movable wall. A stationary partition is provided between the two movable walls. In order to increase the axial stiffness of the booster casing, the partition is provided with bolt projections extending in both directions therefrom and are rigidly connected to the appropriate end walls of the casing. The ends of the bolt projections at the end walls form anchor means for connecting the booster to a master brake cylinder and to a supporting surface of a motor vehicle.

Abstract: An apparatus for use in the generation of impulses, comprising a stepped piston assembly having a large piston and a small piston mechanically linked to one another and reciprocable between forward and rearward positions with the large piston being located in a large cylinder and having a large rearward face in communication with a reservoir for compressed fluid, and with the small piston having a small forward face for delivering the impulse; wherein the stepped piston assembly has an auxiliary piston located between the large piston and the small piston which auxiliary piston is mechanically linked to the large piston and which is reciprocable in an auxiliary cylinder, and wherein there is provided a valve through which fluid can flow from the volume enclosed by the large cylinder forward of the large piston into the volume enclosed by the auxiliary cylinder rearward of the auxiliary piston.

Abstract: This invention relates to a pneumatic cylinder and valve control system in which a block and two plates bolted to the block form one end of the cylinder. This block and plate combination, moreover, provides the housing for the valves and conduits that comprise the pneumatic control system for the operation of the cylinder. To produce greater force, moreover, two pistons mounted within the cylinder on the same line of action both are in fluid communication with the pneumatic control system.

Abstract: A vibration motor comprising a rotor arranged within a cylindrical chamber having opposed radially arranged reciprocating pistons within cylinders opening into the chamber. Circumferential grooves formed in the rotor surface sequentially open the cylinders to a pressurized fluid outlet passageway, to move each piston outwardly, and to a fluid exit passageway to drain the cylinders for inward movement of the pistons. The pistons are axially aligned with and coupled to each other for producing rapid, low amplitude beam vibration. This is a division of application Ser. No. 898,905, filed Apr. 24, 1978, now U.S. Pat. No. 4,154,641.

Abstract: A hydraulic drive for the die closing unit of an injection molding machine in which at least one power cylinder and power piston with a coaxially attached auxiliary cylinder opens and closes the molding die by executing the opening and closing travel with a differential piston action in the power cylinder and/or with the auxiliary cylinder, while valve-closable bypass channels in the power piston are kept open. The closing of these channels switches the drive from an accelerated travel mode to a high-pressure die clamping mode.An annular valve plunger cooperates with a valve seat on the power piston to open and close the bypass channels, several alternatives of guiding and hydraulically moving the valve plunger being contemplated.