Abstract: In vacuum brake boosters for motor vehicles, the vacuum casing is conventionally made of sheet steel. The vacuum casing is subjected to mechanical and pneumatic forces which have to be absorbed by the casing components. This makes it necessary to construct the casing components so they are strong enough to take these forces. The result of such construction is, however, high costs and high weight. To eliminate these disadvantages, the invention provides a brake booster wherein the vacuum casing includes a pipe therein extending in approximately coaxial of the longitudinal axis of the vacuum casing and connected to the transverse end walls of the vacuum casing, the pipe enclosing the master cylinder push rod, and the movable wall of the brake booster is sealed relative to the pipe and slidable thereon.

Abstract: A hydraulic jack having a piston and a cylinder in which the piston has at its head a cavity the dimensions of the cavity and the constructional materials of the cylinder and the piston being selected so that hydraulic pressure applied within the cylinder acts to deform the cylinder wall and the parts of the piston defining the cavity in such a manner that, over the normal rate of operating pressures of the jack the clearance between the piston and the cylinder remains within the capacity of the sealing means arranged between the piston and the cylinder to provide an effective seal.

Abstract: A hydraulic cartridge suitable for releasing stores in aircraft relies on a ressurized piston rod which extends upon release of hydraulic pressure. The piston rod is enclosed in a cylinder and connected to a source of hydraulic fluid. Upon arming of the piston rod a hydraulic liquid is pumped into the piston rod and forces out a gas via an accumulation piston. Upon complete filling of the piston rod, a trigger is held in place by the pressurized fluid. Upon release of pressure, the pressure on the trigger becomes unbalanced and a spring releases the trigger from the piston rod permitting it to extend.

Abstract: A pressure actuator is provided for a valve having a housing and an actuating stem, wherein an annular housing is attachable at one end of the valve housing and a cylindrical piston element is concentrically fixedly mounted to the other end of the annular housing. A cup-shaped cylinder is provided to cooperate in sliding and sealing relationship with the exterior of the piston. The cylinder defines an annular space between its exterior surface and the interior bore of the annular housing and spring elements are mounted in the annular space. If desired, an indicating stem passes through a bore in the fixed piston element and is interiorly engaged with the movable cylinder element, thus providing an indicating actuator wherein the total length of the actuator is not substantially in excess of twice the stroke of the actuator.

Abstract: A remotely operated valve, typically for use as a downhole safety valve, adapted to be connected in-line between two pieces of well pipe or other fluid-conducting members, the valve being rack-and-pinion operated and characterized by including a combined piston and rack member with the piston concentric with a through bore of the valve and with the rack eccentric with respect to the through bore, the eccentric disposition of the rack and associated support members making it possible to achieve a dependably operable valve of minimum transverse dimensions without increased complexity or cost of manufacture.

Abstract: A hydraulic actuator and system for driving a subsurface reciprocating pump. The actuator is double acting and comprises a piston reciprocable in a cylinder on a guide tube, so that the maximum volume of the chamber below the piston is greater than that of the chamber above the piston, and the lower working area of the piston is greater than its upper working area. Ports in the cylinder above and below the piston are connected to a valving and control arrangement, and a source and receiver of hydraulic fluid and an accummulator are also provided. The valving arrangement is controlled so that when the piston reaches a lower level of travel fluid is discharged from the upper chamber to the receive, to enable upward movement of the piston, and when the piston reaches an upper limit of travel discharge of fluid from the upper chamber is interrupted and flow of fluid from the lower chamber to the upper chamber and accummulator is enabled. Several valving and control arrangements are disclosed.

Abstract: A fluid actuator where an outside cylinder envelopes an inside cylinder producing four chambers, two for the power stroke and two for synchronization, for application where two or more cylinders are to drive a single load such that all cylinders advance at the same rate by cross plumbing synchronizing chambers. The combination is provided with valve means which opens at the end of each stroke to realign the actuators.

Abstract: A hydrostatic power steering system with constant volume feedback compensation including first and second steering cylinders. Each cylinder has a housing containing a piston with an attached piston rod extending through one end of the housing. The pistons and piston rods form a head chamber and two feedback chambers within each of the cylinders. The outer ends of the piston rods are connected to a pair of steerable wheels and also to each other by a mechanical link which allows the piston rods to move simultaneously. A control valve is also present which selectively controls the passage of a pressurized fluid from a supply source to a head chamber of either of the cylinders. The cylinders, which have their feedback chambers fluidly connected together, are manually operated by a steering wheel which actuates a metering pump connected across the fluid passages.

Abstract: An air cylinder including a piston adapted to be stopped freely in any position as desired includes an automatic restoring type air cylinder member and a hydraulic cylinder member. The piston is formed with a hydraulic cylinder chamber having fitted therein a hydraulic fixed piston of the hydraulic cylinder member so that the piston can move freely in a cylinder body. An oil chamber defined by the end of the hydraulic fixed piston and the end of the hydraulic cylinder chamber is communicated with an oil tank via an oil passage mounting a check valve that can be opened by pressing means including a pilot piston and other parts.

Abstract: A variable speed multi-cylinder assembly is provided with expandable bushing seals to block leakage of fluid from higher speed stages to lower speed stages.

Abstract: Discussed herein is a rapid actuating device for a hydraulic actuator utilizing two or more relief valves to control the hydraulic flow of the actuator for various loading or no loading conditions in order to speed up the required operation time.

Abstract: In a press with two parallel, spaced apart multiple-acting cylinders that have their respective pistons connected to end portions of a beam to which a bending or forming tool is secured, the cylinders are respectively fed from effectively separate pressure fluid sources providing equal pressures and flow rates. For synchronization of piston extension through an initial rapid advance, the chamber of each cylinder that is normally pressurized for retraction of its piston is connected in feedback relation to the pressure fluid source for the other cylinder, so that fluid expelled from a leading cylinder augments the fluid supply to the lagging one. The system further comprises a pair of sensors, one for each beam end, and a synchronizing bleed-off valve for each sensor.

Abstract: A compact valve actuator for operating a valve of the butterfly type or the like. The actuator comprises a pair of joined pistons which respond by simultaneous reciprocation to introduction of operating fluid such as air into the actuator. Means such as a linkage for connecting the actuator to a valve is provided, such means being connected to the pistons interiorly thereof for minimizing the actuator size for a given required stroke. One of the pistons at a bearing surface thereof, rides on a guide means received interiorly of the piston thereby further enhancing the compactness of the actuator. The surface of the guide means is pressurized with the operating fluid applied to that one piston whereby risk of operating fluid leakage across that piston at the bearing surface thereof is substantially eliminated.

Abstract: A linear fluid actuator having two pistons and two cylinder chambers in tandem to provide redundancy when supplied from independent pressure sources. The actuator is balanced in that the actuator output force is equal in extend or retract positions. The two cylinder chambers are made from separate housings to prevent crack propagation between the chambers and dual piston rod construction is provided to enhance redundancy.

Abstract: A method and apparatus are disclosed for displacing a crane lift hook and hook cable to follow the relative vertical motion between a crane and a loading deck such as occurs between floating vessels and a fixed crane. In the method, the hook cable is paid out or reeled in to maintain the hook a substantially constant distance from the deck in order to facilitate loading or unloading of cargo from the hook. The apparatus for achieving the method includes a vertically displaceable sheave over which the lift cable is reeved, a power ram to displace the sheave, and motive means operating the power ram. Preferably, the power ram is subjected to a constant upward pneumatic force to provide at least a portion of the force for displacing the moveable sheave upwardly to reel in the cable, such as in response to an upward heave of the deck relative to the crane.

Abstract: A hydraulic actuator, readily assemble and disassemble, which can be used for effecting actuation of food processing machinery or bulk bait or other commodity dispensers. Since it is necessary that such devices be safe and non-polluting, components which come in contact with the hydraulic fluid can be made of plastic so that tap water can be utilized as the hydraulic fluid.The actuator is made readily assemble and disassemble by including devices for quick and easy sealing and locking of the component parts. These devices have only a minimal number of subcomponents.

Abstract: The invention relates to a thrust reverser for a jet engine of an aircraft, which comprises two symmetrical doors pivotally mounted about an axis which is transverse and substantially diametrical to the jet of said engine and which is disposed downstream of the jet exhaust pipe thereof, the doors each being pivoted due to two diametrically opposite hinges and occupying a folded or stowed position in which they form part of the fairing of the engine or fuselage of the aircraft, or an unfolded or opened out position in which they are disposed transversely to the jet, while at least one longitudinal jack is provided at the level of a hinge, for the simultaneous control of the doors via connecting rods.

Abstract: A hydraulically-operated road breaker comprises a casing with a tool mounting and housing an oscillatory piston/striker and cylinder arrangement. A sequence valve mounted in the casing controls pressurization and exhausting of the piston to produce power and return strokes of the piston. Pilot port means positioned in the cylinder of the device are uncovered, at the end of each return stroke of the piston, to allow a valve-actuating flow of hydraulic fluid through the port means to change over the sequence valve and thereby cause stroke reversal of the piston. Manually-operable stroke selection means provide for adjustment of the position of the piston in the cylinder at which the valve-actuating flow occurs, whereby to vary the piston stroke.

Abstract: Herein disclosed is a hydraulic actuator which comprises an outer cylinder; an inner cylinder attached at its one end to the axial inner one end of the outer cylinder in coaxial relation with the outer cylinder to define an annular gap between the outer and inner cylinders; a piston having a hollow bore axially extending from its one end to the other end and closed at the other end and slidably received in the annular gap; and a locking mechanism temporarily locking the piston with the outer cylinder upon the farthest movement of the piston to the other end thereof; the locking mechanism including a locking member coupled with one end portion of the piston and which is radially movable, a ram resiliently received in the other end of the inner cylinder and having an inclined stepped portion and a hollow bore axially extending from its one end to the other end and opened at the other end, and an annular locking groove formed at the inner periphery of the other end of the outer cylinder, whereby the locking memb

Abstract: A tooth forming machine disclosed provides high production output and accurately controlled tooth forming due to the provision of equal displacement hydraulic cylinders which reciprocate die racks on upper and lower base portions connected by a base connecting portion and preloaded deflection control connections. Each cylinder includes a hollow housing, a slidable piston received within the housing, a hollow connecting rod secured to the slidable piston and projecting outwardly from the housing, and a stationary piston received within the hollow rod while allowing movement of the slidable piston. An annular pull chamber and a push chamber of the same cross-sectional area are defined by the cylinder components and alternately fed pressurized hydraulic fluid from a closed loop pump system while fluid from the other chamber is returned to the pump system in order to extend or retract the cylinder and thereby move the associated die rack in one direction or the other.

Abstract: A device for controlling two output elements pivotally mounted with respect to two stationary elements is provided with two coaxial rectilinear double action pressure fluid jacks. The two stationary elements are respectively secured to the ends of a stationary outer longitudinal elongated member while the two pivoting elements are respectively secured to the ends of pivotal inner longitudinal elongated member coaxially arranged in said outer member. The jacks are of annular configuration and formed between the outer and inner aforesaid members with a common median bottom and annularly slotted cylinder-heads remote from each other. The tubular piston rod of each jack extends in leak-tight manner through the annularly slotted cylinder-head and is angularly positioned on the one hand, with respect to the corresponding stationary element by a first set of guides and on the other hand with respect to the corresponding pivoting element by a second set of guides forming an angle relative to the first set of guides.

Abstract: The invention provides a hydraulically-driven reciprocatory tool comprising piston with a shoulder reciprocable in a cylinder, and a shuttle valve for controlling supply of fluid to a first face of the piston, the fluid producing a force on the first face which is alternately greater than and less than a constant bias force applied to a second face of the piston, wherein the position of the shuttle valve is determined by the pressure of fluid in a fluid connection between the shuttle valve and first and second ports in the wall of the cylinder, the fluid connection including a first non-return valve for preventing flow of fluid from one of the ports to the shuttle valve and a second non-return valve for preventing flow of fluid from the shuttle valve to the other of the ports. Preferably, each non-return valve has associated with it a variable throttle in the fluid connection and further means are provided for controllable flow of fluid along a branch of the fluid connection.

Abstract: A fluid power cylinder comprising a cylinder barrel, a guide rod received within the cylinder barrel and a piston slidably received within the cylinder barrel over the guide rod for rectilinear movement, means for slidably keying the piston to the guide rod whereby the piston is locked against rotation with respect to the guide rod about the longitudinal axis thereof, a guide rod holder rotatably received in the end cap for rotation coaxially with the piston and the guide rod, a pin connecting the guide rod and guide rod holder so that the guide rod is locked against rotation with respect to the holder about its longitudinal axis yet is permitted a limited degree of tilting about the end received in the guide rod holder, and a cam lock associated with the end cap for releasably clamping the guide rod holder against rotation.

Abstract: This invention relates to a non-rotatable fluid powered nozzle and valve combination which includes a cylinder having a piston reciprocally received therein for movement between two reciprocated positions and which defines two separated fluid chambers therewith. A piston rod secured to the piston is slidably received through one end of the cylinder, the cylinder being provided with two ports communicating with said two chambers, respectively. The piston and piston rod conjointly having a longitudinally extending passage therethrough. A hexagonal pin is disposed in one of said chambers and is slidably received in sealing relation by a hexagonal portion of the aforesaid passage. The pin is secured in the other end of the cylinder for limited radial but against longitudinal movement with respect to the cylinder.

Abstract: An engine of the air-cooled, super-charged type which includes a stationary piston, a cylinder movable relative to the piston and operable in a first position to provide a compression chamber between adjoining ends of the cylinder and piston. In a second position, the compression chamber is opened to provide purging air flow from a compressor stage. A cooling air flow is provided about the surfaces of the cylinder and piston in both positions of the cylinder and during its travel between those positions.In a different embodiment of the engine, the internal combustion portion of the engine just described above is combined with a gas turbine stage. Upon firing of the fuel in the compression chamber and the subsequent opening of the chamber, the flow of hot gases is applied to provide a further rotative force to the turbine wheel.

Abstract: In a disc brake in which the brake applying mechanism is actuated by movement of a first pull rod, the hydraulic actuator which effects movement of the pull rod comprises an assembly of piston and cylinder members of which one is rigidly fixed with respect to a housing and the other is movable relative thereto and acts on the first pull rod. A second pull rod is coupled to the first pull rod and is used for parking or emergency braking.

Abstract: A pressure medium servo-motor, especially for servo-steering systems, in which a working piston operating in a working cylinder is provided with a piston pressure surface actuatable by the pressure in one working pressure chamber of the working cylinder for producing a servo-force directed in the sense of the relative movement of the working piston with respect to the working cylinder; the piston pressure surface of the working piston is thereby reduced with respect to the reference value fulfilling the equilibrium condition of the piston pressure forces in the neutral position of the working piston, by a reducing piston which includes a pressure disengaging surface actuatable by the pressure in the working pressure chamber and a relief pressure surface actuatable by the pressure in a relief pressure chamber.

Abstract: A telescopic fluid ram or thruster utilizing pressurized gas and having an inner and outer piston that slides within a cylindrical bore including a central probe which is tapered and extends into the bore of the inner piston where it will cause the inner piston to move under high pressure while the gas escaping from around the tapered area produces a holding force to hold the outer piston in place until the inner piston is fully extended, at which time the outer piston will extend under a reduced pressure.

Abstract: An apparatus for selectively moving, for instance alternately or simultaneously rotating and displacing in axial direction, a machine element mounted to be rotatable and axially displaceable, comprising a motor, a hollow cylinder and a piston displaceable in said hollow cylinder. The piston is provided with a connection element for rigidly connecting it with the machine element. The piston also has a lengthwise extending opening which is sealed towards the outside at the side of the connection element and at the other end there extends into said lengthwise extending opening a drive shaft connected with said motor. This drive shaft at the side of the connection element has an end which together with the inner surface of the piston forms a first sealing section forming a sealed sliding seat, said drive shaft at the region of its end connected with the motor possessing a second sealing section which together with the hollow cylinder or an element rigidly connected therewith forms a tightly closing sliding seat.

Abstract: The positioning of the piston rod of a double acting hydraulic cylinder is accurately controlled by means of applying hydraulic pressure, created by the controlled displacement of a fluid independent from the primary fluid system, against the piston of a servo-cylinder which controls the servo-valve for the double acting cylinder. As the piston rod of the double acting cylinder moves, the pressure on the servo-cylinder is relieved and the servo-cylinder is returned to a balanced condition, restoring the neutral position of the servo-valve. In another embodiment the application of pressure to a fluid system independent from the primary fluid system is sensed by an electro-hydraulic transducer and a proportional electric signal is produced for controlling the electro-hydraulic servo-valve of the double acting cylinder. As the piston rod of the double acting cylinder moves, fluid is displaced, relieving the sensed pressure and returning the servo-valve to a neutral position at a new setting of the piston rod.

Abstract: A double-acting hydraulic cylinder includes a hollow cylinder body with a closed end and an end with a first rod opening. A first hollow piston and rod assembly, having a second rod opening at the piston end, projects through the first rod opening and slides in the cylinder body. A second hollow piston and rod assembly, secured at the rod end to the hollow cylinder body, projects through the second rod opening and slides in the first hollow piston and rod assembly. The first and second hollow piston and rod assemblies cooperate to form a first variable volume chamber. A rod secured to the rod end of the first hollow piston and rod assembly slidably projects into the second hollow piston and rod assembly and cooperates therewith to form a second variable volume chamber. The first variable volume chamber is connected to a first port in the cylinder body and is expandable and contractable in response respectively to retraction and extension of the first hollow piston and rod assembly.

Abstract: A control cylinder assembly for servo-steering systems including a fluid pressure circuit and steering shaft and an output shaft, in which a servo piston is supported during axial travel by axially spaced sleeves connected to a housing cover and the sleeves form circumposed fluid areas, and the piston forms opposed variable-volume operational areas, all of the areas being operatively connected in a fluid pressure circuit.

Abstract: A pressure regulator comprising a body having an inlet, a first channel, an outlet for passage of gas therethrough and a chamber, a valve located within the channel between inlet and outlet for regulating outlet pressure, the inlet being in effective communication with the chamber through the valve, and a slide contacting the valve, reciprocally moveable within the chamber of the body so as to open or close the valve, biased in a direction tending to open the valve, and responsive in a direction tending to close the valve to pressure of gas which has passed through the valve into the chamber, featuring in one aspect a seal located between the body and slide to prevent the escape of gas therebetween, the seal having an annular base and an annular lip resiliently connected to the base, the base and lip forming a pocket for the gas so that the pressure of the gas helps to bias the lip outward from the base to provide an improved sealing effect, and featuring in another aspect a valve having a reciprocally moveab

Abstract: A compact rack and pinion steering gear having a hydraulically operated power cylinder concentric with respect to an internal cylindrical tube slidably supporting a pinion driven rack. The piston of the power cylinder is slidably mounted in the power cylinder and on the internal tube so that the teeth of the rack can pass through the plane of fluid sealing means adjacent to one end of the power unit to provide for a shortened rack length. The power cylinder is actuated by fluid pressure and is operatively connected to a rotary valve by one external line and by an internal passage in the valve housing. Protective flexible boot seals are provided at each end of the assembly which are pneumatically interconnected by an internal passage formed by existing structure in the assembly.

Abstract: An equal area displacement hydraulic cylinder includes a hollow reciprocal piston rod and piston, and between said cylinder and rod, a first chamber communicating with a first port for retracting the piston rod. A rod end closes said piston rod and includes an attachment device. A hollow tube extends within the piston rod and is anchored at one end to the cylinder and terminates in a second port. A stationary piston is mounted on the other end of said tube. Said tube defines a second chamber communicating with the rod end and second piston for advancing the piston rod when said second port is pressurized. The working area of the reciprocal piston is the same as the working area of the rod end, whereby equal rod force is applied to the reciprocal piston rod in either direction.

Abstract: The brake, including a brake housing, is characterized by a housing having an inwardly extending flange forming a pressure chamber with an annular piston slidably positioned in the brake housing, and the annular piston and a secondary piston are operatively associated with opposed sides of the inwardly extending flange to form pressure chambers therewith for individual actions in the brake. Spring means operatively engage the secondary piston for moving the same into operative pressure braking position for fail safe braking operation. Air pressure is supplied to the two pressure chambers or cylinders for controlling brake release and braking action.

Abstract: A hydraulic actuator for producing translational movement over a long distance having two jack cylinders with pistons mounted for reciprocal movement and connected to a worm wheel through a worm gear. When a piston is driving, the worm gear acts as a rack to turn the worm wheel and when a piston is being returned to its starting position the worm gear rotates. Means are provided to alternately switch from one cylinder to the other.