Abstract: Provided is an electrohydrostatic actuation system including an emergency shut-off circuit to be actuated stably with a simple configuration. The electrohydrostatic actuation system includes: a hydraulic cylinder (24) including a piston (25) to which a valve element is connected, a first chamber (24A), and a second chamber (24B); a hydraulic pump (21) configured to supply hydraulic fluid to the first chamber (24A) or the second chamber (24B); a servo motor (M) configured to drive the hydraulic pump (21); a shuttle valve (11) configured to establish communication to a downstream side under a state in which a hydraulic pressure generated by the hydraulic pump (21) is maintained; a solenoid valve (12) configured to receive the hydraulic pressure via the shuttle valve (11) as a pilot pressure; and a logic valve (13) including a first port configured to receive the pilot pressure from the solenoid valve (12), and a second port to be communicated to the first chamber (24A) of the hydraulic cylinder (24).

Abstract: An artificial muscle tentacle and method for manufacturing an artificial muscle tentacle, and a computer readable medium for controlling an artificial muscle tentacle are disclosed. The artificial muscle tentacle includes two spacers and a central core that connects the two spacers. The artificial muscle tentacle also includes at least two Z-Twist actuators and at least two S-Twist actuators. The Z-Twist actuators and the S-Twist actuators are disposed around the central core and in between the two spacers connecting the two spacers. The actuation of one or more of the Z-Twist actuators and the S-Twist actuators actuates the artificial muscle tentacle.

Abstract: This disclosure includes various embodiments of apparatuses for encapsulating and stopping a flowing mass of fluid (e.g., liquid such as water, or gas such as air) to extract the kinetic energy from the mass, and for exhausting the mass once stopped (spent mass, from which kinetic energy has been extracted). This disclosure also includes various embodiments of systems comprising a plurality of the present apparatuses coupled together and/or one or more of the present apparatuses in combination with one or more flow resistance modifiers (FRMs). This disclosure also includes various embodiments of methods of extracting kinetic energy from a flowing mass of fluid (e.g., liquid such as water, or gas such as air) by stopping the mass, and for exhausting the mass once stopped (spent mass, from which kinetic energy has been extracted). This disclosure also includes embodiments of mechanical energy-storage or accumulation devices.

Abstract: The disclosure relates to a method of monitoring an electrohydrostatic actuator, wherein the electrohydrostatic actuator comprises a hydraulic pump drivable by an electric motor and a hydraulic activator drivable by means of the hydraulic pump to move a component, in particular an aircraft part. The method include detecting the instantaneous speed of the electric motor; detecting an instantaneous position of the activator; detecting a parameter that relates to an instantaneous operating point of the electrohydrostatic actuator; determining a state variable relating to an efficiency of the electrohydrostatic actuator on the basis of at least the detected speed and the detected position in dependence on the detected parameter; and determining a state of the electrohydrostatic actuator on the basis of the currently determined value.

Abstract: A generator is described comprising in particular a vertical supply column that can be filled with a certain quantity of liquid, an intake valve disposed at a base of the vertical supply column, and a leaktight tank communicating with the vertical supply column via the intake valve, which leaktight tank can be filled with liquid. The generator also comprises an exhaust valve disposed on the leaktight tank and capable of releasing pressure generated in the leaktight tank, and a piston-forming device disposed inside the leaktight tank so as to be immersed in the liquid contained in the leaktight tank. This piston-forming device is capable of being set in reciprocating movement between an upper position and a lower position, the piston-forming device comprising a first, float-forming portion capable of bringing the piston-forming device into the upper position and a second portion forming an output shaft.

Abstract: A hydraulic powering system includes a hydraulic cylinder, an accumulator, and a manifold assembly. The hydraulic cylinder includes: (i) a hydraulic cylinder construction having a hydraulic cylinder wall and first and second hydraulic cylinder end caps forming an internal volume, a piston constructed to slide within the internal volume between the first and second hydraulic cylinder end caps and dividing the internal volume into an extend region and a retract region, and a piston rod extending from the piston and through the retract region and one of the first and second end caps to outside the hydraulic cylinder; (ii) an extend port in fluid connection with the extend region of the hydraulic cylinder; and (iii) a retract port in fluid communication with the retract region of the hydraulic cylinder.

Abstract: The present invention relates to an electronic balance with a windshield having a door to be automatically smoothly opened and closed. Provided is an electronic balance including a balance main body including a weighing mechanism connected to a weighing pan, a windshield configured to form a weighing chamber by covering the weighing pan, slidable doors provided in the windshield and constituting portions of the weighing chamber, holders configured to support the doors from upper portions in a hanging manner, guide members configured to engage with the holders and slidably support the holders, and air cylinders connected to the holders and configured to slide the door through the holders. The holders supporting the doors in a hanging manner are directly moved by the air cylinders, so that the doors can be smoothly opened and closed.

Abstract: The invention provides an actuator device, which has: an output element, which is acted on by a fluid and as a result is movable into a holding position; two solid-state actuators, which are able to be activated alternately; a coupling element common to the solid-state actuators; a discharge duct, via which the fluid is able to be discharged from the output element; and at least one valve element, which is adjustable between a blocking closed state and an open state, in which the valve element allows the fluid to be discharged from the output element via the discharge duct and allows the output element to move from the holding position into at least one yielding position, wherein the valve element is actuable, via the coupling element of the respective solid-state actuator, by the respective activation of the solid-state actuator and is able to be moved into the closed state.

Abstract: A rotary drive device has a fluid-actuated rotary drive, which has a drive housing and a drive unit rotatable relative thereto. The drive unit has a pivot piston and a drive shaft connected thereto, whereby the drive shaft projects from the drive housing on an axial front side with a drive section. On the rear side, several components are mounted in axial succession on the drive housing of the rotary drive, which together with the rotary drive form a uniformly practicable drive assembly. These components include a valve carrier device carrying a control valve arrangement, a pneumatic connection unit, and an electronic control unit electrically connected to the control valve arrangement. A robot arm is also proposed, which includes the rotary drive device as an arm joint.

Abstract: A hydraulic control system of an automatic transmission for a vehicle provided with an ISG system is disclosed. The hydraulic control system may include: a mechanical hydraulic pump driven by an engine; a linear solenoid valve to control hydraulic pressure generated by the mechanical hydraulic pump; a first switch valve to selectively supply or not to supply controlled hydraulic pressure to one of friction members; an electric hydraulic pump driven by electric energy; and a second switch valve to selectively supply the hydraulic pressure, generated by the electric hydraulic pump, to the one friction member or to the linear solenoid valve. The hydraulic control system supplies the hydraulic pressure to one of the friction members operated at a gear stage where starting control is performed.

Abstract: A hydraulic drive carries out a method for discretely changing a positional output on the hydraulic drive. At least one displacement cylinder incrementally supplies or discharges the cylinder volume to or from the drive by displacing the cylinder piston element from a starting to an end position depending on at least one input signal. The piston element is repeatedly displaced from starting to end position and back to discretely change the positional output correspondingly to the supplied or discharged displacement volume. The cylinder is hydraulically connected to a pressure medium source supply or return line while displacing the piston element from starting to end position. The changed positional output is restored in a successive step. The cylinder chambers of the displacement cylinder are hydraulically short-circuited by a short-circuit line hydraulically separated from the supply or return line when returning the piston element from the end to the starting position.

Abstract: Energy-recuperating vibration damper having a cylinder in which a displacer executes a limited operating movement in a working chamber so that a pressurized fluid is supplied to a fluid motor which drives a generator. A compensation chamber compensates for a change in volume of the pressurized fluid. A pressure accumulator is provided in addition to the compensation chamber, which pressure accumulator communicates with and is parallel-connected to the fluid motor.

Abstract: There is set forth herein an actuator having a housing and a piston assembly. The piston assembly can have a piston and a piston rod extending from the piston. In one embodiment, the housing can receive the piston and a portion of the piston rod. The piston assembly can define a piston assembly interior and a fluid reservoir can be located within the piston assembly interior. A chamber region within the interior of the housing can be separated by the piston assembly to define a piston side chamber and rod side chamber. The piston assembly can be moveable so that respective volumes of each of the piston side chamber and the rod side chamber are variable. For operation of the actuator by movement of the piston assembly within the interior of the housing, fluid can be moved between the reservoir and the chamber region.

Abstract: Disclosed is a direct drive generator for a wind turbine, the generator including a rotor, a stator configured to remain stationary relative to the rotor, and at least one bearing connected to the stator. The rotor includes at least one rotor part extending circumferentially about an axis of rotation and a plurality of active materials arranged on a side of the at least one rotor part. The stator includes at least one stator part extending circumferentially about the axis of rotation and positioned adjacent to the at least one rotor part, and at least one winding arrangement supported by the at least one stator part and facing the plurality of active materials. The bearing is flexibly connected to the at least one stator part, wherein the bearing abuts the rotor part to help maintain a gap between the at least one winding arrangement and the active materials.

Abstract: An electro-hydraulic actuator (EHA) includes a hydraulic circuit having a plurality of pressure compensated flow control valves for limiting the maximum flow rate through the fluid conduits regardless of the loads imparted on the actuator. In one embodiment of the EHA, a plurality of combination manual override/thermal expansion valves that simplify the manufacture of the EHA.

Abstract: A balance having at least one adjusting device (2, . . . ) having a drive, wherein the drive of the adjusting device is configured as a fluidic drive (4, . . . ), to which pressure can be applied by a pressure source disposed outside the scales via a pressure connection.

Abstract: In an automotive servo-assisted mechanical transmission, an electro-hydraulic actuation group has an actuation unit, a power unit able to provide hydraulic pressure to the actuation unit and an electronic control unit, the actuation and power units being equipped with respective components that are all mounted on a hydraulic casing of the actuation unit so as to define with one another a single assembly structurally separated from the electronic control unit, at least part of the components being equipped with respective electrical connectors that are arranged in a manner such that they can all be engaged by a same multiple electrical connector device.

Abstract: An actuation system includes a pump assembly configured to form a pump chamber, an actuator having first and second chambers and a movable member and configured to convert pressures applied to the first and second chambers into a movement of the movable member, and a valve section. The valve section has a plurality of positions set by a controller, and the plurality of positions includes a first position in which the valve section opens the first flow path and closes the second flow path, a second position in which the valve section closes the first flow path and opens the second flow path, and a neutral position in which the valve section closes the first and second flow paths.

Abstract: A hydraulic drive system for an actuator uses a pair of pressure compensated hydraulic machines to control flow to and from the drive chambers of the actuator. The capacity of one of the machines is limited in a motoring mode to determine a maximum rate of efflux from one of the chambers. The pressure of fluid supplied to the other of said chambers is maintained at a predetermined level to provide motive force. The machines are mechanically coupled to permit energy recovery and charge an accumulator to store surplus energy.

Abstract: A cylinder device (1) according to the present invention includes: a cylinder (2); a piston (3) slidably inserted into the cylinder (2); a rod (4) inserted into the cylinder (2) and connected to the piston (3); a rod-side chamber (5) and a piston-side chamber (6) partitioned by the piston (3) within the cylinder (2); a first on-off valve (9) provided in the middle of a first passage (8) allowing the rod-side chamber (5) to communicate with the piston-side chamber (6); a second on-off valve (11) provided in the middle of a second passage (10) allowing the piston-side chamber (6) to communicate with the tank (7); and a pump (12) for supplying liquid to the rod-side chamber (5).

Abstract: A door operator includes a housing, a first pressure compartment; a second pressure compartment, a drive unit disposed in the housing and coupleable to a door via an output shaft, the driving unit being associated with the first pressure compartment, a hydraulic pump in hydraulic connection with the first and second pressure compartments, a motor in driving relationship with the hydraulic pump, and a spring force accumulator disposed in the housing. The spring force accumulator is associated with the second pressure compartment and coupled to the drive unit.

Abstract: The invention relates to an electrohydraulic actuator comprising a body (1) that defines a cylindrical cavity (2) in which a piston (3) slides in leaktight manner and divides an inside volume of the cavity into two chambers (A, B) of variable volume, the piston being associated with at least one rod (4) passing in leaktight manner through an end wall of the cavity, the actuator including a bidirectional pump (5) having two ports (P1, P2), each connected to one of the chambers, an electric motor (8) for selectively driving the pump in one direction or the other, the pump being placed inside the piston of the actuator so as to move together therewith.

Abstract: The hydraulic linear actuator system of the present invention includes a pump that is configured to rotate in a single direction at a substantially constant velocity. Both the direction and flow rate of fluid through the system is controlled by adjusting the positional relationship between the stator and the rotor of the pump. This positional relationship is adjustable between a forward flow state, a non-flow state and a reverse flow state. The hydraulic linear actuator is responsive to the flow of fluid through the system so as to be displaced in a first direction by the forward flow state of the pump and in a second direction by the reverse flow state of the pump.

Abstract: In a directional control valve device, a first passage connects a second port with a first port by using a part of a movement path of a moving valve element when the moving valve element is in a position of a first end. A second passage connects the second port with the third port by using an internal passage of the moving valve element when the moving valve element is in a second end. The moving valve element is provided with a first check valve for permitting a flow in the internal passage only in the direction from the third port to the second port. When a fluid pressure is applied to the third port, the fluid pressure presses the moving valve element toward the second end so that the first passage is closed, and the first check valve is opened to open the second passage.

Abstract: The hydraulic linear actuator system of the present invention includes a pump that is configured to rotate in a single direction at a substantially constant velocity. Both the direction and flow rate of fluid through the system is controlled by adjusting the positional relationship between the stator and the rotor of the pump. This positional relationship is adjustable between a forward flow state, a non-flow state and a reverse flow state. The hydraulic linear actuator is responsive to the flow of fluid through the system so as to be displaced in a first direction by the forward flow state of the pump and in a second direction by the reverse flow state of the pump.

Abstract: An axle driving apparatus in which a hydraulic pump and a hydraulic motor which constitute a hydrostatic transmission are disposed on a center section. In a horizontal portion of the center section are provided a pair of linear oil passages in parallel to each other. A pair of arcuate ports are provided on a pump mounting surface formed on the horizontal portion of the center section. The pair of arcuate ports are substantially perpendicular with respect to the direction in which the oil passages extend. The axis of slanting movement of a movable swash plate of the hydraulic pump extends laterally of the vehicle body on which the axle driving apparatus is provided. The rotating direction of an arm provided on a control shaft for slantingly operating the movable swash plate is coincident with the operating direction of a control rod connected with a speed changing member. Thus, the link mechanism for connecting the speed changing member and the control arm for the movable swash plate is simplified.

Abstract: According to one embodiment of the invention, a method for biomedical imaging includes directing time-varying excitation light at a surface area of a light scattering material, the material comprising a fluorescent target. Time-varying emission light from the fluorescent target is detected, substantially at a two-dimensional sensor surface, in response to the time-varying excitation light stimulating the fluorescent target. The time-varying emission light is filtered to reject excitation light re-emitted from the material. A three-dimensional image of the fluorescent target is generated based on the detection substantially at the sensor surface.

Abstract: The invention regards a hydraulic cylinder (1) or a plug comprising a hydraulic cylinder for operation of anchoring and or sealing devices, where the hydraulic cylinder comprising a cylinder chamber (6), a piston head (4) within said cylinder chamber (6) forming two sub chambers (7, 7?) of said cylinder chamber (6) one on each side of the piston head (4), and a piston rod (5) which runs through the piston head (4) and said two sub chambers (7, 7?) or only one of said cub chambers. The hydraulic power unit (8) for operation of the hydraulic cylinder (1) is situated at least partly within the parts forming the hydraulic cylinder (1) itself, preferably the piston head (4) and or the piston rod (5).

Abstract: Actuator assemblies comprise an actuator element and two piezoelectric assemblies, with the two piezoelectric assemblies being configured and arranged for controlling movement of the actuator element. In some example implementations, the first piezoelectric assembly and the second piezoelectric assembly are constructed and arranged so that a temperature dependency of the first piezoelectric assembly is cancelled by the temperature dependency of the second piezoelectric assembly. In a first example embodiment, a first piezoelectric assembly comprises a first or main piezoelectric diaphragm connected to the actuator element for displacing the actuator element in response to displacement of the first piezoelectric diaphragm. The first piezoelectric diaphragm and the second piezoelectric diaphragm are fixedly mounted to a movable carriage.

Abstract: The hydraulic linear actuator system of the present invention includes a pump that is configured to rotate in a single direction at a substantially constant velocity. Both the direction and flow rate of fluid through the system is controlled by adjusting the positional relationship between the stator and the rotor of the pump. This positional relationship is adjustable between a forward flow state, a non-flow state and a reverse flow state. The hydraulic linear actuator is responsive to the flow of fluid through the system so as to be displaced in a first direction by the forward flow state of the pump and in a second direction by the reverse flow state of the pump.

Abstract: The invention provides a choke system with hydraulic circuits which provide choke valve positioning that can be varied by the use of incremental steps. The incremental movement action in either the opening or closing direction is accomplished through the use of one of the two hydraulic slave cylinders which can either add or subtract a fixed volume of hydraulic fluid from the choke actuator. A series of check valves provides direction for flow in the hydraulic lines, locking of the choke actuator, and re-filling of the slave cylinders during operation. The system eliminates excessive lines or solenoid valves and avoids the need for mechanical locking mechanisms. Preferred embodiments include a “fast close” system which, instead of running through a series of steps to close the valve, provides valve control in a fast close line to move the choke actuator to the full closed position from anywhere in the travel over a shorter period of time than through normal stepping operation.

Abstract: The system includes a hydraulic powered actuator. A pump system having first and second hydraulic lines is coupled to the first and second ports, respectively and is capable of providing hydraulic fluid to either the first and second lines. First and second pressure sensors are coupled to the first and second lines, respectively. A third line is coupled between the first and second lines and includes first and second valves mounted in series therein. Preferably, the first and second valves are capable of latching in the open position. A reservoir is coupled to the third line between the first and second valves. A shut off valve is included for cutting off the flow from the reservoir.

Abstract: A power steering system includes a reversible-type oil pump supplying hydraulic fluid to first and second pressure chambers of a hydraulic power cylinder through first and second passages and having first and second discharge ports, and a branch passage conveying part of hydraulic fluid discharged from the discharge ports of the oil pump to the outside of the pressure chambers of the power cylinder, wherein the branch passage has a passage sectional area greater than a total leak sectional area of the oil pump.

Abstract: A power steering apparatus includes a hydraulic power cylinder, and a reversible pump driven by a motor. A steering assist sensor senses a steering assist force provided to a steering wheel. A controller ascertains a pump discharge quantity of the reversible pump, and a cylinder volume variation of the pressure chambers of the hydraulic power cylinder; and calculates a leak quantity of the reversible pump from a difference between the pump discharge quantity and the cylinder volume variation. The controller controls the motor to cause the motor to produce a desired fluid pressure in accordance with the steering assist force and the leak quantity.

Abstract: A hydraulic swinging-leaf door drive for swinging doors includes an actuating piston, which acts on a drive shaft. A hydraulic pump acts on the actuating piston by way of a hydraulic circuit. The hydraulic circuit is designed as a closed circuit.

Abstract: A magnetohydraulic motor with a positive displacement pump that pumps hydraulic fluid to and from the two sides of a bi-directional piston that provides the motor's output force and motion. Motion control is provided by properly controlling valves that selectively open and close fluid passageways between the actuator member and each side of the piston.

Abstract: A tandem electrohydrostatic actuator (70) broadly includes a first piston (22) operatively arranged in a first cylinder (23), and a second piston (24) operatively arranged in a second cylinder (25). The pistons are coupled to move together. The first piston has a small extend area (35) and a large retract area (36). The second piston has a large extend area (38) and a small retract area (39). The large areas (36, 38) of the pistons are equal to one another and the small areas (35, 39) of the pistons are equal to one another. A reversible fixed-displacement first pump (45) has equal inlet and outlet flows supplied to the small areas of the first and second pistons, respectively. A reversible fixed-displacement second pump (40) has equal inlet and outlet flows supplied to the large areas of the first and second pistons, respectively. The total volume of the fluid in the actuator remains constant at all positions of the pistons.

Abstract: The present invention is a hydraulic actuated artificial muscles for use with orthetic devices, prosthetic devices or as an actuator for other applications in medical or robotic devices. Working fluid is pumped between two expandable fluid-containing cells, which are complimentary active elements of the artificial muscle. This eliminates the need for a storage reservoir, thereby providing a self-contained, force efficient device. Each of the preferred embodiments describe has one or more expandable fluid-containing cells that are defined by at least one flexible wall. The flexible walls are configured so as to have elastic properties that are limited to predefined directions of expansion and contraction.

Abstract: A hydraulic actuator that is capable of substantial actuation but does not require a conventional pump, uses only deflectable membranes and passive valves, or, at most, a minimum of active valves, and, under certain circumstances, may be free to move when the actuator is de-energized, is provided. The actuator utilizes the deflectable membranes to move fluid throughout the actuator. The movement of the fluid actuates a shaft or other suitable device, as required.

Abstract: An hydraulic power system having a reversible motor operating a pump to deliver liquid under pressure to operate an actuator mechanism, where the motor is submerged within the liquid inside a reservoir. Flow direction of the liquid is controlled by alternating the direction of rotation of the motor and pump.

Abstract: A control system for swing cylinders to position a boom on a backhoe or the like includes a pair of double acting hydraulic cylinders on the backhoe frame operatively connected to the boom for swinging the boom with respect to the frame, a closed circuit pump arranged in a closed circuit with the hydraulic cylinders such that the control on the pump is the sole means of controlling the cylinders.

Abstract: A hydraulic system manifold having a body, a counterbalancer in the body and a flow controller in the body is disclosed. The body has first and second pump ports, first and second cylinder ports, first and second compensator ports and first and second supply conduits in communication with the first and second pump ports, the counterbalancer and the flow controller. The counterbalancer is in communication with the first and second supply conduits and the cylinder ports, to communicate hydraulic fluid between the first and second supply conduits and the first and second cylinder ports while counterbalancing hydraulic fluid pressure in the first and second supply conduits. The flow controller is in communication with the first and second supply conduits and the compensator ports, to control the flow of hydraulic fluid between the compensator ports and the first and second supply conduits to supply and store hydraulic fluid in a volumetric compensator in communication with the compensator ports.

Abstract: An electrohydraulic actuator has a housing divided into pump and cylinder portions respectively containing a centrifugal impeller driven through a hub by an externally mounted motor, and a pushrod actuated by a piston and arranged to advance the piston and pushrod to deliver thrust when the motor is operated. The major parts except the motor and the pushrod are castings and only one size castings are required for a large range of thrust capacities. The impeller casting is machined to a diameter suitable for a desired thrust and a motor of required speed and horsepower for that thrust capacity is selected to drive the impeller.

Abstract: A load control device applicable on agricultural machinery in general and in particular on machinery used for direct planting, so that the working components in contact with the ground will maintain the same load constantly at all times for any ground profile condition. An oil-pneumatic device is provided with a fluid compressor connectable to the tractor's power take-off by a cardan shaft and an electromagnetic clutch that can be powered from the tractor's electrical system or by an independent source, including a compressor with its associated pressurestat which governs it in order to maintain the air pressure required by the circuit. The compressor supplies a tank of compressed air, to which is connected at least one hydraulic cylinder whose upper and lower chambers are each connected to intermediate air and oil collecting reservoirs.

Abstract: A pneumatically driven hydrostatic actuator and a pneumatically driven recirculating hydraulic actuator are provided. Each of these actuators consists of a hydraulic pump fluidly coupled to an actuator. The pump is driven by a low inertia pneumatic motor that extracts pressure energy from pressurized gas and converts it to rotary motion. The pneumatic motor is preferably made from stainless steel A286 so that it can operate using pressurized hydrogen gas. The components of both actuators are in a closely coupled relationship so that they can be arranged in a compact unitary package.

Abstract: An improved hydraulic door actuator comprising a hydraulic fluid pump having first and second ports; integral operating cylinder and fluid control apparatus including a barrel coupled at each end to the first and second ports of the hydraulic fluid pump; a piston fluidly sealed within the barrel; and means for controlling the flow of fluid of the hydraulic fluid pump to and from the barrel disposed between the barrel and the first and second ports such that the door automatically slows to a stop upon opening or closing wherein the fluid flow control means comprises a plurality of openings disposed along the length of the barrel for bypassing pressurized fluid from the barrel.

Abstract: A hydraulic cylinder has a piston in it with a rod projecting out of the cylinder and connectable with a tool which is operable by movement of the piston rod. A high pressure space is defined in the cylinder at one side of the piston and a low pressure space is defined at the other side of the piston. A partition defines the other end of the low pressure space. A diaphragm on the other side of the partition defines an equalizing space between the diaphragm and the partition. A low pressure line is in communication with the low pressure space and with the equalizing space. A change over valve in the lines to both the high pressure space and the low pressure space enables connection of high pressure from a pump either to one space or to the other space in the cylinder while always permitting communication from the low pressure line to the equalizing space, the connection to the equalizing space is in the low pressure line between the change over valve and a non-return valve at the pump.

Abstract: Hydrostatic drives for wave generating apparatus in swimming pools require a large amount of energy. A hydrostatic drive for the wave generating apparatus is provided which allows that part of the kinetic energy of the rearwardly moving water to be transformed into hydraulic energy, which in turn is used to impart onto the water a forward movement.

Abstract: A dual axis actuator consisting of two fluid cylinders having the fluid inputs to the cylinders connected in parallel to a source of pressurized fluid, resulting in an automatic sequencing of cylinder rod drives. The cylinder rod encountering the least resistance to motion extends first until it reaches a stop, followed by the extension of the second cylinder rod. In the preferred embodiment of the invention, the source of fluid input to the two fluid cylinders is derived from the fluid port of a third fluid cylinder having its cylinder rod driven by an external power source. By utilizing two port fluid cylinders, the dual axis actuator can be adapted to provide a sequence of drives for powering workpiece transferring units in a multiple workstation transfer press. Such a system provides an automatic sequencing of translations for engaging and lifting workpieces for movement to a subsequent work station, followed by lowering and retracting from workpieces to allow the next stroke of the press.

Abstract: A hydraulic system manifold having a body, a counterbalancer in the body and a flow controller in the body is disclosed. The body has first and second pump ports, first and second cylinder ports, first and second compensator ports and first and second supply conduits in communication with the first and second pump ports, the counterbalancer and the flow controller. The counterbalancer is in communication with the first and second supply conduits and the cylinder ports, to communicate hydraulic fluid between the first and second supply conduits and the first and second cylinder ports while counterbalancing hydraulic fluid pressure in the first and second supply conduits. The flow controller is in communication with the first and second supply conduits and the compensator ports, to control the flow of hydraulic fluid between the compensator ports and the first and second supply conduits to supply and store hydraulic fluid in a volumetric compensator in communication with the compensator ports.