Abstract: An oil well pumping unit. The pumping unit has a vertical support column residing adjacent a horizontal support base at a generally transverse orientation. The pumping unit has a standing sheave fixed proximate an upper end of the vertical support column, a carrier bar configured to be attached to a polished rod along the front face of the vertical support column, and a traveling sheave configured to move up and down along the vertical support column. A near-vertical actuator resides along the horizontal support base, and is connected to the traveling sheave. Cyclical movement of the linear actuator causes the traveling sheave to reciprocate up and down along the vertical support column such that upward movement of the traveling sheave produces a downstroke of the polished rod, while downward movement of the traveling sheave produces an upstroke of the polished rod. The linear actuator remains in tension at all times during movement of the polished rod.

Abstract: A regenerative shock absorber that includes a housing and a piston that moves at least partially through the housing when the shock is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor, in turn, drives an electric generator that produced electric energy. The electric energy may be provided to a vehicle, among other things. The regenerative shock absorber may also provide ride performance that comparable to or exceeds that of conventional shock absorbers.

Abstract: A servo valve assembly includes a housing defining a cylindrical cavity having a central axis, and a spool disposed in the cavity and co-axially aligned with the central axis. A pair of transition portions define opposing conical cavity surfaces each connect a respective one of first and second cylindrical cavity portions with a third cylindrical cavity portion. The spool comprises a pair of blocking members projecting radially, and each of the blocking members defines a conical blocking surface opposing a respective one of the conical cavity surfaces to define a fluid flow passage therebetween. A cone angle of each conical blocking surface relative to the central is equal to a cone angle of the opposing conical cavity surface relative to the central axis. The spool is moveable along the central axis to vary a flow area of the flow passages between the conical blocking surfaces and the conical cavity surfaces.

Abstract: A shock absorber including: a first cylinder having an interior, first and second ends and defining an axis, wherein the interior includes a damping fluid chamber and a damping piston movably mounted therein for movement between the first and second ends, wherein the damping piston is mounted on a first end of a shaft, wherein the first end of the shaft is movably retained within the interior of the first cylinder; first and second bypass openings configured for opening into the damping fluid chamber at first and second axially spaced-apart positions; a bypass channel fluidly coupling the first and second bypass openings; a fluid metering valve; and a floating piston dividing a portion of the shock absorber into a gas chamber and the reservoir chamber, wherein the fluid metering valve and the floating piston define the reservoir chamber there between.

Abstract: A cylinder unit includes a cylinder, a rod guide, a piston, a piston rod, and a rebound member provided between the rod guide and the piston to absorb impact generated when the cylinder unit is fully extended. The rebound member includes a coil spring arranged around an outer circumference of the piston rod and a pair of upper and lower holder members fitted to the fixing portions formed in both ends of the coil spring so that the piston rod is inserted into a shaft center hole. The center portion formed between the fixing portions of the coil spring has a diameter smaller than that of the fixing portion.

Abstract: A control system for a reciprocating device which includes a switching valve for directing fluid supply under pressure to one of two drive lines in an alternating manner, means for alternating the switching valve, and an exhaust circuit including and exhaust outlet, a first flow restrictor disposed between one drive line and the exhaust outlet, and a second flow restrictor disposed between the other drive line and the exhaust outlet. The system may include a selection valve for alternately connecting one of two drivelines to the exhaust outlet.

Abstract: A shock absorber has an upper cylinder, a piston valve mounted on a lower end of the upper cylinder, a free piston slidably mounted in the upper cylinder and dividing the upper cylinder into an air chamber and an upper oil chamber, a lower cylinder slidably mounted around the lower end of the upper cylinder and has a lower oil chamber. Since the free piston and the air chamber are disposed in the upper cylinder, the shock absorber has a compact structure. Furthermore, when the upper and lower cylinders slide relatively, the free piston slides accordingly to regulate volume of the upper oil chamber and to provide a damping effect. The hydraulic oil in the shock absorber does not contact air and therefore no air permeates into the hydraulic oil.

Abstract: The invention relates to a vibration damper, especially for damping retraction or extension springing forces on motor vehicles, which includes a pressure medium cylinder (2), in which a piston (3) with a piston rod (3) is axially slidably arranged. The piston divides the pressure medium cylinder (2) into a retraction chamber (5) and an extension chamber (6), in which an electrorheological or magnetorheological fluid is contained as a pressure medium. The retraction (5) and extension chambers (6) are connected with one another at least by a throttle gap (7), in the region of which at least one field force generating element (17) is arranged. At least one further non-return check valve (14) is arranged in a further gap (13) between the pressure medium chambers (5, 6). The invention is characterized in that the length of the throttle gap (7) is divided by a gap intersection or gating point (10) into a first throttle gap section (11) and a second throttle gap section (12).

Abstract: A plunger-cylinder assembly for a press including a plunger which is accommodated at least in part in a cylinder while separating the interior of the cylinder into two partial chambers along the cylinder axis. A relieving device which counteracts an increase in pressure of a fluid accommodated in the first partial chamber is disposed in at least one first partial chamber the increase in pressure being caused by a movement of the plunger along the cylinder axis in the direction of the first partial chamber. A hydraulic press encompassing such a plunger-cylinder assembly is also described.

Abstract: The invention is a bi-fluid actuator for precise bi-directional movement and positioning of a mechanical object or load. The bi-fluid actuator includes a pneumatic fluid container defining opposed first and second pneumatic fluid chambers, and having a first mechanical object secured between the chambers; a hydraulic fluid container defining opposed first and second hydraulic fluid chambers, and having a second mechanical object secured between the first and second hydraulic chambers; a pneumatic fluid controller; and, a hydraulic fluid controller. Directing pneumatic fluid into either the first or second pneumatic chambers, while controlling flow of hydraulic fluid between the first and second hydraulic chambers, controls movement and positioning of the mechanical objects which may be secured to a load.

Abstract: In a boiling water reactor controlling each control rod hydraulically by driving a solenoid valve, the control system comprises an operation control means 41 having a duplicated data processing unit for generating sequence patterns based on the timing of the driving sequence based on the control information provided manually, a transmission control means 42 for creating a command word corresponding to each control rod being controlled based on said sequence pattern, and mutually communicating each command word between duplicated data processing units and computing the AND logic of said data within a predetermined time difference, and when the computed result coincide, transmitting the selected command word serially; a transmission unit 32 for receiving said command word and performing protocol conversion thereto, and transmitting the same to a plurality of transmission branch units positioned downstream as the control command; and a solenoid valve drive circuit 31 for driving the control rod drive unit corres

Abstract: A pneumatic cylinder having internal hydraulic dampening device for cushioning the motion of a pneumatic piston (44) at its end of stroke. The hydraulic device includes a pair of hydraulic pistons (50, 52) cooperating with a pair of hydraulic cylinders to form a pair of hydraulic chambers (58, 64), which communicate with each other by a restricted flow passage (74). When the pneumatic piston nears its end of stroke, one of the hydraulic pistons is moved to compress the corresponding hydraulic chamber, forcing hydraulic fluid through the restricted flow passage, to the other hydraulic chamber. The flow of hydraulic fluid through the restricted flow passage slows the pneumatic piston, thereby cushioning the end of stroke motion. The restricted flow passage can include a plurality of flow passages which are sequentially closed by pins (136, 138, 140, 142) connected to one of the hydraulic pistons, as the hydraulic piston moves, to vary the restriction in the flow passage.

Abstract: A suspension system (20) controls the amount of compressible fluid (42) within struts (28) to determine spring rate coefficients (Ks) and dampening coefficients (Bs) for the struts (28). The spring rate and dampening coefficients (Ks, Bs) are selected to provide forces (F) which are a sum of several components, which include a desired target static force (Fd) for balancing various forces acting upon a vehicle chassis, comparison of the target strut force (Fd) to the actual force (F) applied by the respective struts (28), comparison of velocity ({dot over (z)}5) of the chassis relative to a selected reference datum, and a ride height error (erh). Frequency dependant filtering decreases the spring rate coefficients (Ks) when changes in position (Zs) are detected at frequencies (&ohgr;) beneath a threshold level (&ohgr;K), and decreases the dampening coefficients (Bs) when changes in velocity ({dot over (z)}s) are detected at frequencies (&ohgr;) above a threshold level (&ohgr;B).

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: A composite hydraulic cylinder apparatus which has a pneumatic cylinder mechanism, a braking oil hydraulic cylinder mechanism associated concentrically with the pneumatic cylinder mechanism, an oil passage for communicating between the front chamber and the rear chamber of the oil hydraulic cylinder mechanism, and a control valve provided in the oil passage for controlling the flow of the oil. Thus, the apparatus provides high positioning accuracy, a large holding force, economy and small size as a movable element control system, and can be applied as a buffer for the movable element.

Abstract: A vibration isolating and damping suspension strut for vehicle undercarriages comprising an elongated cylinder and piston structure wherein the cylinder is divided into opposed chambers which are in communication with each other by flow restrictive passages formed in the piston or in the cylinder wall. When the strut undergoes a retraction stroke of the piston to absorb loads silicone fluid is compressed in the opposed chambers and transferred from the chamber opposite the piston rod to the rod side chamber through the restrictive passages resulting in heating of the fluid. When the strut rebounds or extends its piston rod fluid is forced to flow through the restrictive passages preferably at a more restricted rate.

Abstract: A pneumatic cylinder having an elongatged cylinder member, a reciprocally movable piston, an elongated slot formed in the cylinder member, a seal for sealing the slot during reciprocal movement of the piston and a transfer means for transferring reciprocal movement of the piston to a workpiece. The above pneumatic cylinder includes a mechanisn for providing pneumatic fluid pressure to a secondary pneumatic unit connected to, and movable with, the piston including a manifold connected with the transfer means and conduit members extending from the pneumatic chambers in the cylinder member for directing pneumatic pressure from such chambers to the transfer means.

Abstract: A digitally controlled air-over-hydraulic actuator includes a pneumatic cylinder and a hydraulic cylinder each having a separate piston and a common connecting rod. The pneumatic piston applies force to the connecting rod urging movement of the hydraulic piston. Bleeding of oil from one side of the hydraulic piston to the other is controlled by means of digital pulses applied to a digital valve that allows oil on either side of the hydraulic piston to flow to the other. The digital valve includes a moving piston having an oil passage that is momentarily aligned with ports to opposite sides of the hydraulic cylinder. A control system senses the differential pressure between opposite sides of the pneumatic piston to produce pulses that accelerate the digital valve piston past the ports, precisely controlling forced movement of the hydraulic piston.

Abstract: A vibration isolating and damping suspension strut for vehicle undercarriages comprising an elongated cylinder and piston structure wherein the cylinder is divided into opposed chambers which are in communication with each other by passages formed in the piston and in a flow restricting shuttle valve mounted on the piston rod. When the strut undergoes a retraction stroke of the piston to absorb loads silicone fluid is compressed in the opposed chambers and transferred from the chamber opposite the piston rod to the rod side chamber through passages in the piston only. When the strut rebounds or extends its piston rod fluid is forced to flow through passages in the shuttle valve member and the piston flow passages at a more restricted rate. The piston flow passages and the shuttle valve are arranged to direct fluid flow toward the outer cylinder borewall to improve heat transfer to the exterior of the strut and minimize heating of the fluid contained in the cylinder chambers.

Abstract: A fluid-pressure-operated, double-acting working cylinder which dampens the final braking of the work piston, includes a cylinder housing with a movable work piston disposed therein, the work piston dividing the cylinder into two work chambers. A piston rod, on which the work piston is mounted, extends through the housing. At least one auxiliary braking member is disposed on at least one side of the work piston in an offset slidable relation to the work piston. A braking arrangement disposed on the auxiliary braking member is controlled by fluid pressure to brake the auxiliary braking member to a desired position within the cylinder. A dampening chamber, a dampening spring configuration is disposed between the auxiliary braking member work piston such that, following braking of the auxiliary braking member, continued movement of the work piston is effectively dampened.

Abstract: An improved double-acting fluid cylinder with primary and secondary chambers of tandem construction, wherein the primary chamber is utilized to provide ram motion in a first direction and wherein the tandemly arranged secondary chamber is provided with a single biasing spring means to resiliently bias the secondary piston and to buffer and control the rate of motion induced in the ram, and also to drive the ram in a direction opposite the stroke of the first direction and at a time subsequent to the stroke so as to temper the ultimate amplitude or extent of motion induced in the ram in response to forces applied within the primary chamber.

Abstract: A shock absorber having a casing and a piston with a piston head mounted thereon and located in a chamber within the casing containing fluid, an annular peripheral groove on the shock absorber head for mounting an annular turbulence inducing member having an L-shaped cross section which is slidable on the bottom surface of the groove from a passive position which it occupies when the piston head forces liquid from one side thereof to the other in a fluid amplification mode and which moves to an active position for creating turbulence within the groove during the rebound movement of the piston head.

Abstract: An expelling mechanism adapted for use with discharge tubes and drain tubes of submarines for ejecting a weapon by compressed air includes a chamber formed with an outlet opening, and adapted to substantially communicate selectively with a storage container holding compressed gas, a discharge valve which may be moved towards the opening in a closing direction, and away therefrom in an opening direction at a selectable opening velocity, and a hydraulic control device for controlling the movement of the discharge valve. The hydraulic control device includes a cylinder adapted to be filled with hydraulic fluid, a piston reciprocally movable along a stroke within the cylinder, and partitioning the cylinder into two cylinder chambers, an overflow channel establishing communication between the cylinder chambers, and a connecting device connecting the discharge valve with the hydraulic control device.

Abstract: The piston comprises, fixed on a rod (9), a central element constituted by a thin perforated disc (8), and two lateral elements (6, 7) in which are provided valve members (21, 22) which cooperate with seats defined by the disc (8). The piston (1) is guided in a cylinder (2) by a ring (16) carried by the lateral elements (6, 7).

Abstract: An improved double-acting fluid cylinder with primary and secondary chambers of tandem construction, wherein the primary chamber is utilized to provide ram motion in a first direction and wherein the tandemly arranged secondary chamber is provided with a resiliently biased secondary piston to buffer and control the rate of motion induced in the ram, and also to drive the ram in a direction opposite the first direction so as to control the ultimate amplitude or extent of motion induced in the ram in response to forces applied within the primary chamber.

Abstract: An exercising device comprising a frame, actuating means, and a double acting hydraulic cylinder used therewith. The hydraulic cylinder includes a container having first and second chambers and passageways for placing the chambers in fluid communication with one another. A piston is slideably mounted within the first chamber and valve means are mounted with the container for preventing fluid communication into the first chamber when the piston is moved in a first direction and for preventing fluid communication around the piston when the piston is moved in a second direction. A piston rod extends into the container for moving the piston in response to movement of the actuating means. A control means governs the fluid flow through a selected passageway from the first to the second chamber to regulate the amount of force necessary to move the actuating means during exercise of a portion of the body.

Abstract: A machine tool having a spindle assembly associated with an indexing tool storage rack on which a number of distinct tools are stored, and a transport or tool carriage for conveying a selected tool between the storage rack and the spindle assembly; and including a control circuit for sequencing the operation of the various component parts of the machine tool for either manual or automatic operation. The spindle assembly includes a variable speed motor drive for rotating a spindle having a drawbar for releasably securing a tool adaptor with the tool to the end of the spindle and which is associated with a push rod operable to control the release of the tool adaptor during a tool changing operation. A spindle gear shifting assembly is operatively connected to the spindle for shifting of the spindle between direct high speed drive and back gear low speed drive or to a neutral position in which the spindle is disengaged from the variable speed motor drive.

Abstract: A machine for performing cutting, roll-grooving and like operations on pipe or tubing. A pneumatically operated head assembly provides for rapid tool advancement to a first predetermined position short of work engagement and hydraulically cushioned advancement therefrom to work engagement. A captive oil supply flow freely through poppet valves which close at first predetermined tool position, and at a controllable rate through a needle valve between the first and second tool positions. Automatic poppet reset occurs for rapid tool withdrawal, readying the apparatus for recycling.

Abstract: An improved type of hydraulic control cartridge with mounting structure and accessorial safety device for installation within both ends of reciprocative pneumatic actuators to permit a safe increase in their speed of operation. The safety device automatically stops the actuator if the hydraulic cartridge malfunctions.

Abstract: A closed circuit power system is disclosed herein having a hydraulic power device incorporated therein which includes an input piston and cylinder assemblage and an output piston and cylinder assemblage connected together by a fluid conduit so as to operate in unison. The input assemblage includes a piston moved by an input ram so as to apply a fluid pressure via the conduit to the output assemblage. The output assemblage includes a pair of pistons operating in unison in separate chambers in response to the applied fluid pressure for moving an output shaft. The pair of pistons include pressure faces against which the fluid pressure is applied which are of equal area but different shape. A selected piston of the output assemblage includes conical forward and rearward faces with a corresponding or matching concave recess in the rear cylinder wall.

Abstract: A gear shaving machine employing plunge cut (radial infeed with no lateral traverse) in which the rate of relative infeed between a meshed gear-like tool and a work gear is controlled by hydraulic escapement mechanism.

Abstract: An actuator 4 for a valve 2 disposed in a gas pipe line 1 is driven directly by the gas pressure in the pipe line, which is tapped off and supplied to the appropriate end of the actuator cylinder via an electromagnetic spool valve 12 or 25. A hydraulic transfer circuit couples the chambers on the piston rod sides of the actuator cylinder, and includes flow control valves 17, 18 for regulating the actuator speed and an oil expansion tank. The latter may be sealed and a positive pressure established therein to facilitate the oil transfer. A hand pump 22 may also be provided to implement the oil transfer and drive the actuator piston from the piston rod side if the gas pressure is too low to power the actuator.

Abstract: Operating means comprise an air cylinder and a hydraulic cylinder mounted in axial alignment. A rod passes through both cylinders, and a piston in the air cylinder is mounted on the rod. A hollow member which is positioned about the rod passes through the hydraulic cylinder and extends from the ends thereof, and a piston in the hydraulic cylinder is mounted on the hollow member and divides the interior of the hydraulic cylinder into first and second chambers. First and second axially adjustable engagement members are mounted on the rod to engage the ends of the hollow member upon movement of the rod in opposite respective directions, whereby movement of the piston in the air cylinder is accompanied by movement of the piston in the hydraulic cylinder. The first and second chambers of the hydraulic cylinder are connected by first and second passageways, each of which is provided with a non-return valve and a flow rate controlling valve. The non-return valves are biased in opposite respective senses.

Abstract: In glassware forming apparatus the reciprocation of a transfer carriage between two operating positions is effected by a cylinder and piston device in which the traverse of the piston is progressively cushioned at the ends of the piston stroke. Members, which are slidably mounted in the piston and protrude from it, close exhaust outlets in an end wall of the cylinder when the piston is at different predetermined distances from the end wall, and these members are positioned in the piston by the action of the end wall for similarly co-operating with corresponding exhaust outlets in the opposite end wall of the cylinder.

Abstract: To prevent rapid collapse of a hydraulic lift mechanism in event of the failure of the hydraulic mechanism (e.g. as by rupture of a pressurized hydraulic line) a rate of flow responsive check valve is provided, either in a separate backup cylinder or at the inlet-outlet port of the lift cylinder, to close off the return flow path of the hydraulic line in the event of sudden depressurization of the hydraulic feed line or other pressure failure in the hydraulic liquid. In normal operation, the check valve does not oppose the return flow since the rate of such flow is insufficient to activate the valve.

Abstract: The improved hydraulically actuated percussion drill described hereinafter is designed to reciprocate a striker piston contained therein regardless of whether or not the striker piston engages the drill steel whereby vibration can be imparted to the drill. The drill includes an overtravel portion that cooperates with the striker piston to prevent metal-to-metal contact of the striker piston with the housing during operation. Means are provided to prevent the loss of fluid from the overtravel chamber whereby the striker piston will be returned to the upper end of its stroke and will not become stalled in the overtravel chamber.

Abstract: A hydraulically controlled pneumatic swinging door operator comprising a pneumatic cylinder with a piston therein, a continuous loop connected to opposite sides of the piston and entrained at its ends over sprockets, one of which makes driving or driven connection with a door, a passive hydraulic system including a cylinder and a piston, the piston of which is carried by the side of the loop opposite the side carrying the pneumatic piston, and passage work in the hydraulic system for controlling the flow of hydraulic fluid in said cylinder from one side of the hydraulic piston to the other side.