Abstract: A detection system includes a drill bit where electro-acoustic transducers operate as a transmitter and/or receiver, are integrated; electronic circuits; a control unit associated with a data storage unit and is powered by an electrical supply system, the processing and control unit for generating driving signals sent to the electro-acoustic transducer acting as a transmitter by the analogue driving electronic circuits, for acquiring signals received from the transducer and for processing the received signals to determine discontinuity interfaces and/or anomalies in pore pressures in geological formations; wherein each of the electro-acoustic transducers is in contact with a pressurised fluid and includes: a tubular body with two end portions opposed to each other longitudinally, internally a first chamber ending with the first end portion and a second chamber on one side adjacent and in fluid communication with the first chamber and, on the other side ending with the second end portion.

Abstract: A motor control device includes an electric current detection result acquisition unit configured to acquire a result of detecting an electric current for operating a motor, an electric current determination unit configured to determine whether or not the electric current acquired by the electric current detection result acquisition unit is greater than or equal to a predetermined threshold value, an operation time setting unit configured to set an operation time period corresponding to the electric current when the electric current determination unit determines that the electric current is greater than or equal to the predetermined threshold value, and an operation control unit configured to perform control for causing the motor to be continuously operated for the operation time period set by the operation time setting unit.

Abstract: A vibration-ram arrangement for introducing a material to be rammed into a ground may include a hydraulic apparatus for generating hydraulic pressure. The hydraulic apparatus may include an internal-combustion motor and a hydraulic pump that is drivable by the internal-combustion motor. The arrangement may further include an exciter arrangement, which is configured to be spatially separate from the hydraulic apparatus and which by way of a hydraulic line is connected to the hydraulic apparatus. The exciter arrangement may have a hydraulic motor and a rotatably mounted unbalanced mass. For driving the unbalanced mass, hydraulic liquid may be guided in a circuit comprising the hydraulic apparatus, the hydraulic line, and the hydraulic motor. The unbalanced mass is drivable by the hydraulic motor to generate vibration movements of the exciter arrangement. The arrangement may also include a support device on which the hydraulic apparatus and the exciter arrangement are disposed.

Abstract: A device having a hydraulic drive for civil engineering work has least one shaft that can be rotated by a hydraulic motor. The hydraulic motor is operated by fluid of a hydraulic circuit that is supplied by a hydraulic pump. The hydraulic motor has a changeable displacement, and means for changing the volume stream are provided. A sensor for measuring the fluid pressure is disposed in the hydraulic circuit, and is connected with a control and regulation unit, by way of which the displacement of the hydraulic motor is adjustable, and by way of which the means for a change in the volume stream can be turned on. The control and regulation unit is set up so that in the event of a pressure drop in the hydraulic circuit, a reduction in the displacement of the hydraulic motor as well as a reduction in the volume stream is brought about.

Abstract: An example includes a hydraulically controllable coupling to couple a rotating input and to an output to rotate, or to decouple the input and the output, with coupling and decoupling modes selected by switching a hydraulic device such as a vane pump between a pumping mode and a mode in which it does not pump. In an example, the system cooperates with a transmission to increase the number of possible gear ratios in some examples.

Abstract: A differential fluid pressure energy conversion system includes a valve (V1) for regulating an input from a pressure source to define a fluid flow; and a lower piston chamber (LPC) in fluid communication with an output of V1, the LPC disposed about a central vertical axis of the system; Further included is a double acting reciprocatable piston (DAP) having an integral lower portion (PI) and an integral upper integral portion (P2), each portion having a bottom radial surface area, the radial surface area of P1 greater than that of P2, an outer peripheral edge of the P1 in fluid-tight slidable continuous contact with an inner complemental surface of LPC, DAP further including an elongate axial channel, co-axial with the vertical axis of the system, the channel extending an entire axial length of the DAP.

Abstract: A hydraulic pressure amplification system for increasing the output pressure in the delivery pipe to or from a ram pump, a spring rebound inertia pump or similar cyclic pumps which deliver a pulsating flow. Said hydraulic pressure amplification system comprises a fluid inlet (29), a fluid outlet (30) and one or more rigid bodies (21) which contain an enclosed convolute passageway extending between the fluid inlet and the fluid outlet. The body or bodies are sandwiched between rigid cover plates (22,23) which respectively contain the fluid inlet (29) and the fluid outlet (30).

Abstract: A fluid energy distribution system that has three general elements; the fluid energy providers; the means for fluid energy distribution; and the fluid drivers. The fluid energy providers input energy into hydraulic fluid in the form of fluid pressure and flow. This energy is then passed to the means for fluid energy distribution wherein the energy from all fluid energy providers moves a set of sliding pistons to turn a connected crankshaft that converts and consolidates the converted energy as torque in the crankshaft. Another set of differently sized sliding pistons connected to the same crankshaft is used to pressurize a fluid and disperse it in its now energized state to the various fluid drivers according to their speed and torque demands. The routing (supply) of the various fluid volumes is done by a computerized control system that operates some of the ports in a series of multi port valves.

Abstract: A drive assembly for connection to the polish rod of a reciprocating pump includes a support frame fixed in proximity to a wellhead. A linear actuator includes a lower portion fixed to the support frame and an upper portion supporting two pairs of direction altering cable guides thereon. Four lengths of cable each include a first portion substantially anchored to relative to the polish rod by a pump bracket, a second portion substantially anchored to the support frame by an anchor bracket, and an intermediate portion extending through a respective one of the direction altering cable guides on the upper portion of the linear actuator between the first portion and the second portion.

Abstract: Low-temperature, continuous “cold” combustion, constant pressure, active chamber motor-compressor unit operating with working compressed air and using a piston travel control device as well as an active chamber, with a cold chamber (29) able to reduce to very low temperatures the atmospheric air that supplies the input (28) of an air compression device (28,25,26,33), which then forces this working compressed air, still at low temperature, in an external combustion chamber (19) fitted with a heating device (19A) at constant pressure where it increases in volume, before its quasi-isothermal transfer in the active chamber (13) producing work, before being expanded in an engine cylinder (2) to produce work again.

Abstract: Systems and methods for implementing a uniflow fluid engine having at least one cylinder having at least one high-pressure input and at least one low-pressure output. In some embodiments, the engine includes piston-operated valves that are related to the piston shaft and pistons that may also act as exhaust valves. In some embodiments, a valve is slidably positioned within the cylinder on the piston shaft, the valve being movable between a first position allowing input fluid to be conveyed through a first passage and blocking input fluid from a second passage, and a second position allowing input fluid to be conveyed through the second passage and blocking input fluid from the first passage.

Abstract: A reciprocating solar engine includes a) a seesawing platform having a central fulcrum support upon which the platform is moveably positioned to reciprocally rotate through a predetermined arc b) a first solar heat-receiving closed container located on the platform on one side of the support and a second solar heat-receiving closed container located on the platform on a second side of the support; c) a connecting tube connecting the first container and the second container; d) a fluid contained within at least one of the first and the second container, the fluid being evaporable from solar heat and condensable from shading from solar heat; e) a roof above and connected to the platform, having at least one window of which is located above the first container and at least one window of above the second container; f) shuttering devices connected to the roof and movable so that one window is closed while the other is open and vice versa; and, g) shutter device controls functionally connected to the shutter device

Abstract: A drive assembly for a reciprocating pump includes a support structure with a linear actuator mounted on the support structure. The linear actuator has a stationary portion and a movable ram portion. At least one direction altering cable guide is mounted to the movable ram portion of the linear actuator. At least one cable is provided having a first end and a second end. The first end is anchored to one of the support structure or the stationary portion of the linear actuator. The second end is adapted for attachment to a polish rod of a reciprocating pump. As the movable ram portion moves, the cable and cable guide configuration provide a mechanical advantage which results in the polish rod reciprocally moving a multiple of the distance travelled by the movable ram portion of the linear actuator.

Abstract: In at least some embodiments, an apparatus includes a hydraulic directional control manifold and a plurality of electric piezopumps. The apparatus also includes an electric piezopump controller that operates the plurality of electric piezopumps in varying combinations to provide generation and directional control of hydraulic power to linear hydraulic actuators using localized closed-loop hydraulic fluid.

Abstract: A pressure balancing device for a transducer is provided. The pressure balancing device comprises: a pressure transmission device having a cross-sectional area and arranged, in use, to be exposed to a fluid; and a fluid chamber having a hollow shaft, the fluid chamber being arranged to be acted on by the pressure transmission device; wherein the cross-sectional area of the hollow shaft is less than the cross-sectional area of the pressure transmission device.

Abstract: We present a high-efficiency crankless reciprocating steam engine that loses only a small amount of energy when the rectilinear motion of its piston is changed into the rotary motion of its driveshaft. The present invention continuously rotates a valve in one direction while alternately introducing steam into two piston housing chambers to generate the rotary force of the driveshaft. Therefore, engine efficiency is greatly increased because the inertial force losses in the valve are much smaller compared to the case when the valve rotation stops or changes direction.

Abstract: An arm structure intended for controlling the impulse valve (5) of the oscillating cylinder which performs a back and forth movement whereupon the oscillating cylinder comprises a cylinder body (14), a cylinder chamber (1) formed into the mentioned body, a piston (2) which can be moved in the cylinder chamber with the help of a pressure media, feeding channels (15, 16, 17) of the pressure media to the cylinder chamber (1) and control devices in order to direct the pressure media to the cylinder chamber to various sides of the piston and away from the cylinder chamber in order to achieve a back and forth movement for the piston and whereupon the impulse valves (5) belong to the control devices the operation of which at least one arm (10); (12), which explores mechanically the position of the piston arm (7) the movement of which arm is adjusted to open the pressure relieving channel of the impulse valve (5).

Abstract: An actuator includes a power source, a cam member driven by power from the power source, a following member moving in connection with a motion of the cam member, an accommodation chamber accommodating an actuating medium, and a punch cylinder outputting the power transmitted to the actuating medium by the following member.

Abstract: The invention relates to a catapult drive for an object to be accelerated, preferably the car of a fairground ride, wherein the object is accelerated by means of a driving element. The movement of the driving element is produced by a flexible drive and a hydraulic cylinder via which all movements of the driving element can be controlled. The invention also relates to a control system for suitably controlling the inventive catapult drive.

Abstract: A toroidal ram actuator comprising a part toroidal shaped cylinder mounted to a first member and a part toroidal piston reciprocally movable within the cylinder, a free end of the piston being mounted to a second member, wherein the first and second members are pivotally attached along an axis and the relative movement between the cylinder and piston produces rotary motion of the first or second member about the axis.

Abstract: A drive assembly for a reciprocating pump includes a support structure with a linear actuator mounted on the support structure. The linear actuator has a stationary portion and a movable ram portion. At least one direction altering cable guide is mounted to the movable ram portion of the linear actuator. At least one cable is provided having a first end and a second end. The first end is anchored to one of the support structure or the stationary portion of the linear actuator. The second end is adapted for attachment to a polish rod of a reciprocating pump. As the movable ram portion moves, the cable and cable guide configuration provide a mechanical advantage which results in the polish rod reciprocally moving a multiple of the distance traveled by the movable ram portion of the linear actuator.

Abstract: Power generation apparatus includes a wing-shaped blade having opposite sides, opposite ends and leading and trailing edges extending between those ends. A lift differential producing device in the blade produces a lift differential at the opposite sides of the blade and that device is switched so that one blade side or the other produces the greater lift. A blade shaft extends along an axis in the blade that is in close parallel relation to the leading edge of the blade and that shaft is fixed to move with the blade. Supports support the blade shaft so that the blade can be positioned in a fluid stream with the leading edge facing upstream and swing about the axis between first and second extreme positions on opposite sides of a neutral position, the blade shaft oscillating with the blade. A coordinating device coordinates the switching of the lift differential producing device with the swinging of the blade so that the switching occurs at the extreme positions of the blade.

Abstract: The invention is a launching system made of a gripping conus connected to a wire that is connected to a winch system, a turning sheave, and a lifting cylinder that is affixed to a base, wherein the winch system has a motor driven hydraulic pump connected to an accumulator system connected to a hydraulic motor that drives a winch drum, and wherein an attached booster system is made of a cylinder connected to accumulator system and a set of sheaves connected to wire that is connected to a gripping conus that moves or stops a cart.

Abstract: A fluid powered linkage (12) has at least three side plates (18) of substantially equal width joined by connectors (17) to form a polygon of variable cross sectional area. An upper plate and a lower plate enclose a variable volume within the polygon. At least one port (37) allows fluid to enter into or leave from the enclosed variable volume in a controllable manner. Seals prevent fluid from entering or leaving the enclosed variable volume other than through the one or more ports. Two abutments (19, 11) are located on the side plates or connectors and the distance between the two abutments varies non-linearly with, but in the same direction as, the variable cross-sectional area. Optionally, an inner surface of one or more of the side plates defines a recess. A preferred linkage has a cross-section in the shape of a diamond or rhombus of varying internal angles, or a half or quarter thereof. In use, the obtuse angle preferably ranges from nearly 180 degrees to about 135 degrees.

Abstract: In a fluid displacement system having a pressure vessel, an expansion vessel, first and second tubes in fluid communication with the two vessels, and an energy source, fluid contained within the system is transferred from one vessel to the other by activating the energy source, which in turn generates pressure in the pressure vessel. The generated pressure in the pressure vessel, in turn, displaces the fluid in the expansion vessel, and the system advantageously has no moving parts.

Abstract: A cable restrained reciprocating blade system is adapted for extracting energy from a moving body of water to facilitate conversion to electric energy.

Abstract: A wellhead mounted pneumatic actuator for bottom hole oil pumps designed for operation by compressed air or gas. The preferred embodiment utilizes a single action cylinder with the downstroke actuated by the weight of the sucker rods and the fluid contained therein. Sufficient relatively high pressure air or gas from an external source is supplied under the piston of the cylinder to lift the piston at all times. A pressure or solenoid control floating piston bleeder valve selectively routes air or gas into the power cylinder on both sides of the piston to accomplish the downstroke. First and second contactors are mounted to cables suspended from a spreader reciprocating with the piston to contact respective first and second pivot arms to pivot the pivot arms into engagement with the respective first and second activator buttons of the bleeder valve to shift the bleeder valve from one position to the other to effectuate the selective routing of air or gas to the top of the piston as well as under the piston.

Abstract: A long stroke deep well pumping unit which employs a fluid motor connected with a polish rod by using a plurality of belts, fixed at either end, to reciprocate the sucker rod through repeated long strokes with a minimum of stress and shock to the sucker rod during directional change.

Abstract: A pressure-driven engine is provided therein with an intake valve and an exhaust valve the opening and closing operations of which are controlled by a combination of the urging force of the respective springs and the attractive force of the respective magnets. The engine automatically repeats reciprocating motion merely by supplying a pressure source such as steam or various kinds of compression gas. The reciprocating motion or the rotational motion converted from the reciprocating motion is utilized as a power.

Abstract: A rotary type hydraulic damper for motorcycle suspension application is disclosed in which a shaft and a housing each containing oppositely extending vanes are arranged for relative rotational movement. The vanes cooperate to define alternately spaced expansion and compression chambers between which hydraulic fluid is passed in response to relative movement between the shaft and the housing. According to one aspect of the invention, a manifold arrangement includes the interconnection of the expansion chambers at one end of the housing and that of the compression chambers at the other end thereof, and a throttling device restricts the flow of fluid between the respective chambers to provide a damping force generator. According to another aspect of the invention the damper shaft provides structural support for the motorcycle drive sprocket, whereby strength requirements for the sprocket bearing case are reduced.

Abstract: A slurry pump has slurry hopper and dual pumping cylinders. The slurry pumping members are driven by opposite-phase actuators. Each actuator has a rigid-hollow-stem partition dividing the space between the actuator plunger and the cylinder into two drive chambers of different areas selectively supplied with pressurized fluid to drive the plunger with a selected force and speed. An associated valve shuts off flow to one of the drive chambers and is controlled at any given time to occupy the same position as a corresponding valve of the other actuator. The valves coordinate supply of fluid to corresponding drive chambers on alternate strokes of two actuators.

Abstract: A hydraulic pump jack is disclosed which utilizes a hydraulic cylinder to provide pumping force to an oil well sucker rod. The hydraulic pump jack may be directly mounted on an oil well casing either above or below ground. A tubular piston rod which may be connected to a sucker rod in telescoping relation for transmitting vertical force without side loading is also disclosed. Apparatus for mounting the piston rod within a cylindrical housing is described. The use of a counter weight system for balancing the pump load is also described.

Abstract: A hydraulic power and control system for operating a reciprocating hydraulic mechanism including pump means connected to the hydraulic mechanism, a continuous torque hydraulic motor, a direction control driven by the motor to sequentially direct hydraulic power fluid to separate inlets of the mechanism, an escapement for restraining the motor at 180.degree. intervals of rotation for sequentially holding the direction control at two separate positions, one for supplying one inlet and the other for supplying the other inlet of the mechanism, and hydraulic limit valves for controlling the escapement when a reciprocating member of the mechanism reaches the end of each stroke. One embodiment has two constant volume hydraulic pumps connected with the hydraulic mechanism through a reversing valve assembly operated by a scotch yoke connected with the escapement.

Abstract: For use with a pumped well having a string of sucker rods connecting to a downhole pump, hydraulic pumping apparatus is disclosed. In the preferred and illustrated embodiment, a polished rod is surrounded by a selectively located sleeve. The sleeve locks to a piston in a hydraulic cylinder. The piston is forced upwardly. The length of stroke is adjusted. The location of the sleeve on the polished rod is likewise adjustable. This enables the device to be adjusted so that any length of sucker rods can be accommodated without requiring cutting sucker rods to achieve a particular length. Moreover, the length of stroke is adjustable to take into account the stroke of the pump and sucker rod elongation during operation.

Abstract: A pump jack having a walking beam oscillated in a vertical arc by a hydraulic actuating cylinder that receives pressurized hydraulic fluid from a variable displacement pump. The hydraulic actuating cylinder is controlled by a hydraulic valve having an operating member mechanically shifted by a second hydraulic actuating cylinder near the end points of the pivotation arc of the walking beam to reverse the direction of movement of the walking beam during the shifting of the operating member of the hydraulic valve. The second hydraulic actuating cylinder is controlled by a second hydraulic valve that transmits pressure to the second hydraulic actuating cylinder from the variable displacement pump and reverses the flow of pressurized hydraulic fluid to the ports of the second hydraulic actuating cylinder near the end points of the pivotation arc of the walking beam.

Abstract: A hydraulic pumping unit is provided that is especially adapted for use for pumping oil from a well, and that provides for independent upstroke and downstroke speed control of the well sucker rod. The pumping unit includes a load sensing, pressure and flow compensated pump that is destroked under no load conditions, a pumping cylinder including a polished rod coupled to the sucker rod, and a unique hydraulic valving assembly that couples the hydraulic fluid pump with the pumping cylinder. The hydraulic valving assembly includes a cylinder control module for independent control of the rates at which the polished rod is raised and lowered, and a signal control module for indicating the upper and lower limits of polished rod travel within the pumping cylinder. The cylinder control module provides for soft turnaround of the polished rod, thereby guarding against stretching of the sucker rod and subsequent degradation of the unit's pumping capacity.

Abstract: My invention relates to pumping apparatus, particularly to a hydraulically-operated pump jack for oil, brine water and the like. The apparatus is fabricated from steel plate to make a strong, but light-weight tower which may be easily transported from one site to another by a small boom truck or gin pole truck. In contrast to pump jacks of the walking beam type which are massive in size, my improved pump jack is compact and is seated on and secured directly to the head of an oil well casing. A vertically-arranged hydraulic cylinder has its piston rod connected to a cross head on which a pair of sprockets are journalled. Chains pass around respective sprockets, one reach of each chain extending upwardly and is anchored to a stationary part of the tower. The other reach of each chain extends upwardly and over and around an upper sprocket journalled on a shaft carried by the upper end of the tower, each chain then extending downwardly to a yoke to which the polish rod is connected.

Abstract: A hydraulic drive apparatus for a wellhead pump jack which utilizes oppositely driven single-acting hydraulic cylinders as actuated by a variable volume pump having flow direction and flow volume controlled by a servo linkage and control lever. The linkage transmits oscillatory sine function motion of the walking beam for movement of the control lever as intermediate biasing force prevents nulling of the system.

Abstract: A torque transfer apparatus includes one or more externally powered energy pumps having a plurality of piston and follower arrangements. The pistons are attached to crankshafts, while the associated followers are controlled by a timing chain driven camshaft. The energy pumps are provided with belt drives to power one or more oil pumps, and the oil pumps provide pressurized oil between the followers and pistons so as to improve power transfer efficiency. Additionally, return lines are provided which permit the pressurized oil to be returned to the oil pump during a return stroke of the associated pistons.

Abstract: A mechanism for moving an element in opposite directions includes a piston connected with the element. The piston reciprocates in a cylinder as high pressure fluid is alternately directed against one side or the other of the piston by a rotatable directional valve. The directional valve is rotated by a gerotor motor. A single rotatable valve element has passages at one end which form a commutator valve for the gerotor motor and ports at the other end which form the directional valve. A passage through the valve element connects the output of the gerotor motor with the directional valve ports. Cushioning means are provided to damp the motion of the piston at each end of its stroke to prevent impact with the ends of the cylinder.

Abstract: The hydraulic operated surface pumping unit of this invention is a counterbalanced cross beam type pumping unit driven by a hydraulic cylinder. The pumping unit can be operated in a first mode of equal upstroke and down stroke speeds or in a second mode of slower upstroke and faster down stroke speeds. The stroke lengths are controlled by cams and are adjustable over a large range. Stroke cycle speeds can be varied by adjusting the output rate of a hydraulic pump used to drive the system. The main hydraulic valve includes intermediate lock positions to hold the pumping unit steady during phase shifts between upstrokes and down strokes and during shut down of the pumping unit. Pressure indicators are provided for optimum counterbalancing of the pumping unit, and a needle valve control for return fluid flow to tank is provided for slow let down of the pump rod for initial tag out settings.

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: The preferred embodiment is directed to an oil well pumping apparatus incorporating a walking beam having a horsehead at one end which connects to the sucker rods in the oil well. The opposite end of the walking beam is supported on a fixed pivot. A hydraulic and pneumatic combination unit connects from a supporting platform to a central point on the beam to raise and lower the beam. The improved apparatus utilizes air pressure to balance the static load on the apparatus and dynamically strokes the sucker rod string by imparting a reciprocating motion through hydraulic power applied at a specified rate to raise and lower the walking beam. A pump and motor system for a closed hydraulic loop is included. Alternate preferred embodiments are disclosed. In one form, a lubricating system is incorporated. First and second alternate forms of pickoff apparatus which powers the pneumatically balanced pumping apparatus is also included.

Abstract: A hydraulically operated pump jack utilizing dual hydraulically operated piston and cylinder assemblies for pivoting the beam of the pump jack and including a unique control arrangement associated with a reversing valve for controlling operation of the piston and cylinder assemblies. The control arrangement includes a hydraulically operated holding valve incorporated into each of the conduits between the reversing valve and the hydraulically operated piston and cylinder assemblies combined with a control piston and cylinder assembly for controlling the operation of the holding valves. A manually operated valve assembly is also incorporated into each conduit to enable conversion of either or both of the piston and cylinder assemblies from double acting to single acting.

Abstract: Apparatus for pumping oil from a well includes a hydraulic pump for reciprocating a sucker rod string. A counterweight is connected to the sucker rod string by a chain strung over sprockets within a compact framework. The hydraulic pump applies a shock absorbing back pressure to the sucker rod.

Abstract: A pump jack for pumping oil and like wells having a polish rod extending vertically out of a well casing is provided including a frame adapted to fit over said well, a hydraulic cylinder depending from said frame generally coaxially of said polish rod, a piston movable in said cylinder and having an end engaging said polish rod, a source of high pressure fluid connected to said cylinder for raising said piston in the cylinder, dump means on said frame simultaneously discharging the raising fluid from said cylinder and by-passing fluid from said source of high pressure fluid to said source of fluid, means on said piston selectively actuating said dump valve from a first position where all fluid from the source of high pressure fluid is delivered to one side of the cylinder for raising the piston to a second position where all fluid from the source and from said one side of the piston is simultaneously returned to the source and to the other side of the cylinder whereby the piston and polish rod are successivel

Abstract: A self-reversing hydraulic control system for use with a device to be driven in opposite directional modes, especially a self-reversing pump driven by such a device. The system depends upon a flow sensing element disposed to sense flow associated with movement of the driven device and adapted to generate a stop signal responsive to the termination of such flow. A means responsive to the stop signal is then effective to shift the system from one directional mode to the other. Also featured is a sensor disposed to receive and transmit hydraulic fluid under pressure to drive the device, stoppage of the flow adapted to cause the sensor to shift position and to transmit pressurized hydraulic fluid pressure, as the stop signal via a hydraulic line. In preferred embodiments the self-reversing hydraulic control system has a two-position 4-way valve which is shifted in position by the hydraulic stop signal.

Abstract: A high torque hydraulic power plant is operated by electrical power through the use of a hydraulic pump, opposing double-ended cylinders containing double-ended pistons and appropriate cycling valve means. Pressure is maintained in the system by a constant pneumatic force applied to the full piston side of each opposing double-ended piston.

Abstract: A fluid actuated power device which includes a reciprocal cylinder rotatably mounted on a central, tubular shaft for back-and-forth movement along the shaft between a pair of end support members. The cylinder has first and second sets of spiral grooves on its outer surface, the first set of spiral grooves being in mesh with the spiral teeth of a first ratchet gear and the second set of spiral grooves being in mesh with the spiral teeth of a second ratchet gear, the ratchet gears being carried by a cylindrical body fixed relative to the shaft. The ratchet gears permit the cylinder to rotate only in one direction relative to and about the shaft as the cylinder moves back and forth along the length of the shaft. The cylinder is coupled by spline means to a gear assembly which, in turn, is connected to a rotatable second shaft, the latter serving as a power takeoff means which can be connected to external work-producing apparatus.

Abstract: An oil well pump jack with dual hydraulically operated piston and cylinder assemblies for pivoting the walking beam of the pump jack and including a unique control arrangement for controlling operation of the piston and cylinder assemblies. The pump jack includes a unique base or skid and an adjustable knee brace assembly to facilitate positioning of the pump jack in properly supported relation to the oil well at the oil well site. The control arrangement for the piston and cylinder assemblies includes a reversing valve, a linkage mechanism for operating the reversing valve to cause controlled oscillation of the walking beam and a cushioning device for controlling acceleration and deceleration of the oscillating walking beam to reduce abrupt tension forces exerted on the polish rod and sucker rods and impact forces imparted to the pump jack during oscillation of the walking beam.