Abstract: A grinding package fitted on robotic arm includes a main body, a pneumatic motor, a bridging part and a grinding tool. The main body is formed with a first space, a second space, a communicating hole communicating the first space to the second space, a connecting wall within the first space, an intake channel, an exhaust channel, openings of the first space and the second space respectively located on each of two parallel sides of the main body, the connecting wall having a ventilation hole. The pneumatic motor includes a motor body within the first space, and a transmission shaft connected to the motor body while extended from the second space through the communicating hole. The bridging part is combined with the main body and the robotic arm, the bridging part closing off the first space, the grinding tool facing the second space and being joined to the transmission shaft.

Abstract: A landing gear controller for an aircraft is configured to: detect an extension time for a landing gear, and if the detected extension time meets a predetermined criterion, provide a warning signal to indicate potential failure of a landing gear uplock hook. The landing gear controller may be in a landing gear system.

Abstract: A pneumatic actuator includes a housing defining a chamber. A diaphragm is positioned within the chamber. A rod member is attached to the diaphragm and is movable between a first position and a second position. A cam member is attached to the diaphragm and to the rod member. The cam member has a cam surface. A deflection rod has a first end portion and a second end portion, where the first end portion of the deflection rod is attached to the housing. A follower is attached to the second end portion of the deflection rod. The follower engages the cam surface of the cam member so as to urge the rod member towards the second position.

Abstract: A stepper motor including: a plurality of actuators, each having an actuation rod movable between retracted and expended positions, the actuation rod having an actuation pin movable along with the actuation rod; and a shuttle rotatable about a shaft, the shuttle having a plurality of pockets corresponding to the actuation pin of the plurality of actuators, the plurality of pockets being partially offset from the plurality of pins such that actuation of one or more of the plurality of actuators moves the actuation rod and corresponding actuation pin into a corresponding one of the plurality of pockets to rotate the shuttle about the shaft.

Abstract: A compressed gas motor and methods comprise a working plunger and a control plunger arranged in the internal space between the working plunger and a closed rear side such as to be mobile in linear direction. The control plunger, in a first position, covers a gas outlet opening and does not cover the gas inlet opening and, in a second position, covers the gas inlet opening and does not cover the gas outlet opening. The control plunger is supported as in a bearing such as to be mobile with respect to the working plunger, and a catch element is arranged on said working plunger and/or control plunger and pulls the control plunger in the direction of the working plunger, at a first distance, when the working plunger moves away from the control plunger, as well as a lavage system comprising said compressed gas motor.

Abstract: A working machine includes: a first switch operable to set an operation amount; a second switch operable by being pressed; a control unit capable of detecting an operation of the first switch and an operation of the second switch, the control unit outputting a control signal based on the operation amount of the first switch and continuously outputting the control signal when the operation of the first switch is detected after detecting a release of the operation of the second switch under a state where the operation of the second switch is detected; an actuator configured to be activated by a hydraulic operation fluid; a solenoid valve capable of controlling, based on the control signal, a pilot pressure; and a control valve configured to supply, based on the pilot pressure, the hydraulic operation fluid to the actuator.

Abstract: An AC motor hydraulic system which utilizes a plurality of centrally controlled AC servo motor driven hydraulic pumps with integrated reservoirs to effectuate rotation of a plurality of stabilizer fins mounted about a vessel to automatically counter unwanted movement of a vessel.

Abstract: This disclosure includes hydraulic apparatuses and methods for redundant actuation of a hydraulic device. Some apparatuses include a hydraulic device having a first hydraulic actuator and a second hydraulic actuator, wherein each of the first and second hydraulic actuators comprises at least a first hydraulic cavity, a second hydraulic cavity, and a piston. Some apparatuses also include a controller coupled to the hydraulic device. In some embodiments, the controller is configured to receive hydraulic fluid from a fluid source via at least two parallel hydraulic lines coupled to the controller, select a first hydraulic line of the at least two parallel hydraulic lines, and transfer the hydraulic fluid from the selected first hydraulic line to a first cavity of the first hydraulic actuator to apply pressure to a first piston to actuate the hydraulic device.

Abstract: A system has an actuator having a rotor or a linear piston, and ports for hydraulic fluid, an electro-mechanical sensor sensing position of the rotor or linear piston, a valve having a 1 plug in a bore of a valve body, the plug having cross bores aligning with passages within the valve body communicating inlet and outlet ports depending on relative position of the plug in the bore of the valve body, a servo motor to move the plug around or along the axis to different positions to align individual ones of the cross bores with individual ones of the passages communicating with individual ones of the ports, and a programmable controller coupled to the electro-mechanical sensor and to the servo motor, the controller enabled to control the servo motor to accomplish programmed movement and position of the rotor or linear piston of the hydraulically-driven actuator.

Abstract: Variable displacement devices and related methods are provided that can be used to change the amount of volume displaced by pistons within corresponding cylinders. The subject matter disclosed herein can relate to variable displacement devices usable as pumps, combustion engines, air compressors, compressed air engines, hydraulic engines, or the like, that can be used to change the amount of volume displaced by pistons within corresponding cylinders while the compression ratio remains substantially constant or can be variable as well depending on the configuration of the variable displacement devices and their components.

Abstract: A pneumatic drive and a method for acquiring the power of a pneumatic drive are specified. A piston is movably disposed in a working space and coupled to a path transducer. A pressure sensor is provided for acquiring an internal pressure of the working space. An evaluation unit of the pneumatic drive is adapted to process the value of a path distance of a movement of the piston acquired by the path transducer as well as a variation of the internal pressure in the working space acquired by the pressure sensor. The variation of the internal pressure is associated with the movement of the piston in the working space. Based on these values, a power of the pneumatic drive can be determined.

Abstract: A hydraulic cylinder is provided. The hydraulic cylinder includes a casing with a longitudinal axis defined therethrough, a first fluid inlet defined in the casing, a second fluid inlet defined in the casing, a first fluid outlet defined in the casing, a second fluid outlet defined in the casing, a shaft extending along the longitudinal axis, a first switching valve mounted to the shaft, a second switching valve mounted to the shaft, and a piston mounted to the shaft between the first switching valve and the second switching valve, wherein the hydraulic cylinder is configured such that when a fluid is supplied to the first and second fluid inlets, the shaft, the first and second switching valves, and the piston oscillate back and forth along the longitudinal axis.

Abstract: A hydraulic system for a work machine may include a first hydraulic cylinder, a second hydraulic cylinder and a monospool assembly in fluid communication with the first hydraulic cylinder and the second hydraulic cylinder. The monospool assembly may facilitate at least one of a cylinder-to-cylinder regeneration flow, makeup flow and supplemental flow to at least one of the first hydraulic cylinder and the second hydraulic cylinder.

Abstract: A hydraulic actuator adapted to be coupled to one or more pistons of a compressed air energy storage (CAES) system includes a housing forming a plurality of aligned bores, with a shaft disposed therein for reciprocating movement. For a three bore configuration, the shaft has three pistons subdividing the three bores into six pressure chambers. Four valves fluidically connected to the six chambers selectively provide pressurized hydraulic fluid, permitting three levels of hydraulic shaft force for each direction of shaft motion.

Abstract: An actuation system for a joint includes an actuator having a piston, an articulating element coupled to the actuator that is driven by the piston to match a gait cycle of an appendage, an energy source engaged with the piston that energizes working fluid within the actuator to drive the piston and generate exhaust gas, a plurality of valves coupled to the actuator, and an exhaust gas holding element coupled to the actuator that is sized to hold a volume of the exhaust gas contained within the actuator.

Abstract: Force multiplication device comprising a low power reciprocable force output device serving to energize, near the end of low force stroke thereof, a coaxially aligned coupling mechanism serving to interconnect to rear shaft of said low force reciprocable force output device, a high power reciprocable force output device comprising a plurality of coaxially disposed, connected and cooperating air cylinders resulting in availability of multiplied force throughout remainder of stroke of low power reciprocable force output device.

Abstract: The invention relates to a method and to a working equipment for actuating a hydraulically movable working element (24), which is provided on a main body (14) of a working equipment (11), comprising at least one main cylinder (19) and at least one additional cylinder (28), which are supplied with pressure medium to generate a pivoting movement, wherein the pivoting movement in the rapid motion mode is actuated in a first working pressure range of the hydraulic control device (32), the pivoting movement in a working motion mode is actuated in a second working pressure range, which is higher than the first working pressure range, the pivoting movement in the heavy load motion mode is actuated in a third working pressure range, which is higher than the first and second working pressure ranges, and the pivoting movement of the working element (24) in the operating modes of rapid motion, working motion or heavy load motion is actuated in accordance with the prevailing working pressure.

Abstract: A device to actuate a contamination cover on a machine bracket is disclosed. The device may include a first transition cylinder mounted on the machine bracket and connected to the contamination cover, a transition circuit connected to the first transition cylinder for transmission of hydraulic pressure to the first transition cylinder; and a transition sensor coupled to the transition circuit to control the transmission of hydraulic pressure to the first transition cylinder. The activation of the transition sensor may permit the transmission of hydraulic pressure to drive the first transition cylinder for transition of the contamination cover from a close to an open position.

Abstract: The present disclosure provides a control system of a powered machine. The control system includes a hydraulic motor configured to drive a track system of the machine. The motor is operable with a variable displacement. A control valve is fluidly coupled to the motor. In addition, the control system includes a controller and an electro-hydraulic valve disposed in electrical communication with the controller and fluid communication with the control valve. The electro-hydraulic valve receives a signal from the controller, and based on the signal, the electro-hydraulic valve hydraulically varies the start of control pressure of the motor.

Abstract: A hydraulic system for a power shovel is disclosed. The hydraulic system may have a cylinder operatively connectable to a dipper door of the power shovel, a reservoir located at and fluidly connected to the cylinder, and an accumulator located at and fluidly connected to the cylinder in parallel with the reservoir. The hydraulic system may further have a control valve disposed between the cylinder, the reservoir, and the accumulator. The control valve may be movable to selectively direct fluid from the cylinder into the accumulator and fluid from the reservoir into the cylinder.

Abstract: An economizer device associable with a linear pneumatic actuator includes a body having openings and a Venturi vacuum generator slidably housed in a first conduit. The device operates between a first operating configuration, where a first opening is supplied with air at an operating pressure and the vacuum generator moves in the first conduit to permit primary flow of air and to reduce outlet pressure thereof from a second opening so as to supply the chamber of the actuator with air at a reduced pressure lower than the operating pressure, and a second operating configuration, where the first opening is connected to the environment at atmospheric pressure and a third opening is supplied with pressurized air with which it supplies the vacuum generator, which creates a vacuum in the second opening in such a manner as to suck air from and create a vacuum in the chamber.

Abstract: An apparatus for compensating for fluid contraction in a hydraulic powered telescoping boom may include a monitor determining the elevation angle of the telescoping boom, a supply of hydraulic fluid, and a fluid control responsive to the monitor. The fluid control provides the hydraulic fluid from the supply to a hydraulic cylinder controlling extension of the telescoping boom when the elevation angle exceeds a predetermined threshold angle to compensate for thermal contraction of hydraulic fluid and thus prevent uncommanded boom retraction. A method in accordance with the invention is also disclosed.

Abstract: A multifunctional cylinder includes: a cylinder housing in which an operating fluid is filled; a rod having one end provided in the cylinder housing and linearly moved in the longitudinal direction of the cylinder housing in accordance with a flow of the operating fluid; and a piston assembly provided at one end of the rod and moved together with the rod and changing a movement amount of the rod per unit time by controlling a passing flow rate of the operating fluid that flows to the other end from one end in the cylinder housing per unit time, and a method for controlling the cylinder.

Abstract: A fluid-driven linear actuator comprises a piston configured for reciprocating motion in a piston chamber and a spool valve in a valve chamber. The valve chamber is fluidly connected to a fluid input and to a fluid output. The spool valve is configured to be hydraulically moved within the valve chamber between a plurality of spool valve configurations, comprising a first spool valve configuration wherein the valve chamber is fluidly connected to the piston chamber to thereby create a first fluid pressure differential which tends to force the piston in a first axial direction and a second spool valve configuration wherein the valve chamber is fluidly connected to the piston chamber to thereby create a second fluid pressure differential which tends to force the piston in a second axial direction.

Abstract: An end cap assembly for a reciprocating air motor comprises a pilot valve and an end cap body. The pilot has a valve stem. The end cap body comprises a central bore for receiving an air motor rod, a valve bore in which the pilot valve is disposed such that the valve stem extends through the end cap body, and an air port extending through the end cap body. The air port has a contour to direct air toward the valve stem.

Abstract: A ram air turbine actuator includes a piston rod arranged in a cylinder. The cylinder and piston rod are configured to move longitudinally relative to one another between retracted and deployed positions. An annular space provided between the cylinder and piston rod, and a fluid flow regulating feature is provided in the piston rod. The fluid flow regulating feature is progressively blocked from the retracted position to the deployed position. The RAT actuator is deployed by initiating a deploy sequence and reducing a volume of an annular space. Fluid flow is forced from the annular space through a flow regulating feature to a cavity. The size of the flow regulating feature reduces to damp the actuator during the deploy sequence.

Abstract: A method of controlling a pneumatic actuator for actuation of a pneumatically actuated device. The actuator comprises a piston and a pneumatic cylinder, the piston is arranged to move axially within the pneumatic cylinder. The piston is moved as a function of a pressure in a pressure chamber of the pneumatic cylinder, and the pressure in the pressure chamber is adjusted by a control unit which controls at least a valve and/or a pressure regulator and/or a pressure generating device. A pilot control component, for the control, is determined as a function of at least a sliding friction force and/or at least a static friction force of the pneumatic actuator.

Abstract: An exemplary hydraulic system includes a plurality of digital valves, each valve fluidly connectable to a corresponding hydraulic load. The digitals valves are operable to fluidly connect the corresponding hydraulic load to a pressure source. The hydraulic system further includes a digital controller operably connected to the plurality of digital valves. The digital controller is configured to assign a priority level so that it is associated with each of a plurality of hydraulic loads, and to formulate a pulse width modulated control signal based on the assigned priority levels. The digital controller transmits the control signal to the plurality of digital valves for controlling the operation of the valves.

Abstract: To provide an axial piston motor (1), comprising at least one main burner (2), which has at least one main combustion space (21) and at least one main nozzle space (23), and comprising at least one pre-burner (3), which has at least one pre-combustion space (31) and at least one pre-nozzle space (33), wherein the pre-combustion space (31) is connected to the main nozzle space (23) by way of at least one hot gas feed (30), that has improved operating and control characteristics even under non-steady-state operating conditions, the pre-nozzle space (33) of the pre-burner (3) has at least one auxiliary hot gas feed (40).

Abstract: A telescopic cylinder comprises a housing, a nestable first sleeve, a nestable second sleeve, and a nestable piston rod. A dividing wall is disposed at at least one of the first ends of the first and the second sleeves thereby defining a first chamber between the housing and the at least one of the first ends of the first and second sleeves, and a second chamber between the at least one of the first ends of the first and second sleeves and the piston rod. A valve extends through the dividing wall for selectively allowing communication from the second chamber to the first chamber when pressure inside the second chamber is above a predetermined pressure. A method of extending a telescopic cylinder where the at least second sleeve extends before the at least first sleeve is also presented.

Abstract: The invention provides for a hydraulic cylinder position sensing and locking system that automatically maintains the position of a lock nut (36) that engages a plunger (16) on a hydraulic actuator such that if hydraulic pressure is lost, the lock nut prevents retraction of the plunger into the hydraulic cylinder (14). The hydraulic cylinder position sensing and locking system also provides for a position sensing feature that allows for the calculation of the axial stroke position of the plunger based on rotary movement of the lock nut. In addition, the invention provides for a synchronous hydraulic cylinder position sensing and locking system and methods of using both the hydraulic cylinder position sensing and locking system as well as the synchronous hydraulic cylinder position sensing and locking system.

Abstract: Provided is a method of and valve assembly for dumping excess fluid during retraction of a cylinder actuator. The method includes pumping fluid with a pump from a piston side of the cylinder to a rod side of the cylinder; opening a first check valve with relatively high pressure fluid from a downstream side of the pump to allow flow into the rod side of the cylinder; and opening an extend relief valve via a first spool with fluid from the downstream side of the pump to allow excess fluid at an upstream side of the pump to return to a reservoir at relatively low pressure.

Abstract: A fluid working machine has at least one working chamber of cyclically varying volume and low and high pressure valves to regulate the flow of working fluid into and out of the working chamber, from low and high pressure manifolds. The low and high pressure valves are actuated by electronically controlled valve actuation means which, when actuated, applies forces to the low and high pressure valve members to open and/or close the respective valves. The low and high pressure valve members are independently moveable and, although the low pressure valve member typically begins to move quickly in response to a shared valve control signal, the high pressure valve member typically moves only after a change in the pressure within the working chamber.

Abstract: An annular valve (1) has an annular valve member (4) and inner and outer annular valve seats (12, 14). Inner and outer sealing ridges (8, 10) are formed either on the annular valve member or on the valve seats. The inner sealing ridges are more resistant to plastic deformation than the outer sealing ridges. They may be thicker, or made from a harder material. Thus, the annular valve better resists damage arising from greater plastic deformation of the inner sealing ridge than the outer sealing ridge due to greater forces (Fi, Fo) acting on the inner sealing ridge than the outer sealing ridge in use.

Abstract: The invention provides a motor-driven movement system for moving a movable element, the system comprising at least two actuators, each provided with means connecting it to the movable element and each dimensioned to be capable, on its own, of driving the movable element, a central control unit being connected to the two actuators in order to be capable of sending a position setpoint (Pos1, Pos2) to one or other of the actuators. According to the invention, the system further comprises control means for simultaneously controlling both actuators in terms of force in response to the position setpoint sent to one of the actuators. The invention also provides a method of driving such a system and a method of testing such a system.

Abstract: A compressed-gas motor has a cylindrical inner chamber closed gas-tight at a first base surface, and a piston arranged so as to be movable along the cylinder axis in the cylindrical inner chamber. A first opening feeds a compressed gas into the inner chamber, and a second opening discharges a gas from inside the inner chamber. The openings are arranged in the cylinder casing of the cylindrical inner chamber, wherein the first opening is arranged between the second opening and the closed first base surface. The first opening is closable by a first piston part and the second opening by a second piston part. The compressed-gas motor has a resetting device which exerts a force on the piston in the direction of the first base surface of the cylindrical inner chamber if the second piston part does not completely close the second opening.

Abstract: An apparatus (10) for compressing and expanding a gas includes a chamber (22), a positive displacement device (24) moveable relative thereto, first and second valves (26, 28) activatable to control flow of gas into and out of the chamber (22) and a controller (80) for controlling activation of the valves (26, 28) that selectively switches operation between a compression and an expansion mode with selective switching between modes being achieved by selectively changing the activation timing of at least one of the valves during the first mode. An energy storage system including the device may be operatively coupled via a rotary device for power transmission to an input/output device, whereby the direction and speed of rotation are preserved during switching, and the input/output device may be synchronised to the grid.

Abstract: A piston-chamber hydro-gravity engine capable of converting the stagnant volume of the liquid matter of sea, lake, pond or artificially made hydro container, to a moving volume of liquid matter that flows back upon itself and in meanwhile exploits this motion as a working agent to produce mechanical kinetic power, capable of being used for mechanical production of kinetic work for hydro-electricity generation, or to be used multi-purposely for other energy needs that demand mechanical kinetic force sufficient to solve energy production problems worldwide forever beneficial to the economy and, friendly to the environment, consisting of particular accessories of mechanisms embodied in a single system of mutual successive co-operation by exploiting gravity, that is the hydro-container (7), capable of creating the means of exploiting the gravity-hydro-static tension of squashing compression exist within the volume of liquid matter of the sea, lake, pond or artificially made containers, the cylinder-chamber (15) a

Abstract: A method of suppressing a pulsation of axial type hydraulic pump/motor includes performing a pressure accumulation operation in which each of ports of each of two pressure accumulation oil passages exclusively communicates with a corresponding one of communication holes and pressure inside one of the cylinder bores is accumulated in a corresponding one of the pressure accumulation oil passages through the communication hole in two levels, the communication holes being provided for each of the cylinder bores to communicate with inside of each of the cylinder bores and having opening portions sliding on the respective ports with rotation of the cylinder block to communicate with the respective ports; and performing an accumulated pressure collection operation in which the pressure accumulated in the pressure accumulation oil passage is collected in one of the cylinder bores in two levels.

Abstract: A method of operating a dual acting hydraulic cylinder comprising the steps of returning a hydraulic fluid from a rod-side chamber to a piston-side chamber of the cylinder during a start phase of cylinder extraction with a speed component and increasing pressure of the fluid during end phase of cylinder extraction with a booster component and permitting the fluid to flow from the rod-side chamber to a reservoir. A hydraulic device for operating a dual acting hydraulic cylinder comprising a speed component arranged to return a hydraulic fluid from a rod-side chamber to a piston-side chamber of the cylinder at a start phase of cylinder extraction and a booster component arranged to increase the pressure of the fluid at an end phase of cylinder extraction.

Abstract: A multiple valve compressor head having a casing defining an intake chamber in selective communication with a cavity through a plurality of one-way intake valves and an exhaust chamber in selective communication with the cavity through a plurality of one-way exhaust valves is disclosed. The casing further defines an inlet port for the entry of gas into the intake chamber and an outlet port for forcing out compressed gas from the exhaust chamber. In operation, the multiple valve compressor head is in operative engagement with a reciprocating diaphragm that draws the gas into the intake chamber and then the cavity during the intake stroke of the diaphragm, while expelling compressed gas from the cavity and through the outlet port during the exhaust stroke of the diaphragm.

Abstract: A timing device for an intermittent vacuum regulator comprises a diaphragm assembly that includes a diaphragm housing, a return spring, and a diaphragm projecting at least partially out of the diaphragm housing. A piston rod is coupled to the diaphragm. A connecting rod comprising an upper free end coupled to the piston rod and a lower fixed end coupled to a valve pin is provided. A piston stop comprising a semicircular C-shaped portion on its front side and a semi-cylindrical portion on its back side is also provided, wherein the piston rod directly pushes and pulls the connecting rod, such that during an intermittent operation of the timing device to actuate a valve assembly, the upper free end of the connecting rod rotates about the valve pin but is being limited in a range of motion by the piston stop.

Abstract: Arrangement for damping of a piston movement in a compressed air cylinder (10; 20), which arrangement includes a compressed air cylinder (10; 20), a valve device, a compressed air device, and a control unit. The control unit controls valve devices such that the movement of the piston is damped before the piston reaches the casing of the compressed air cylinder. A method for control of the arrangement is disclosed.

Abstract: An arrangement for providing a throttle cross-section for a fluid flow. The throttle cross-section can be varied depending on a pressure difference present across the throttle cross-section. The arrangement is designed such that the polarity of the pressure difference, by which the throttle cross-section can be varied and/or changed. It is thereby possible to use the arrangement for fluid flows that alternate in the flow direction thereof.

Abstract: A bootstrap accumulator system includes an actuator cylinder that drives an accumulator piston through a multiple of nested actuator sleeves, comprising a multistage actuator cylinder.

Abstract: A staged rocket apparatus includes first and second stages connected by a releasable connector. A plurality of pressurized gas struts are connected between the first and second stages and provide a separating force urging the first and second stages apart. The gas struts are held in a telescopingly collapsed first position by the releasable connector. The separating force is maintained at a minimum value so long as the releasable connector holds the struts in their first position. When the releasable connector is disconnected the separating force increases due to gas flow through a metering passage having a progressively increasing flow area from a high pressure chamber to a low pressure chamber.

Abstract: A digital hydraulic controller has at least two rows of valve elements: one can connect a supply line to a controller output, the other can connect the controller output to an outlet line. The valve elements of each row are connected in parallel and are switchable individually or simultaneously in different combinations with each other and have different flow cross sections. The valve element with the smallest flow cross section is present twice in the row. A system unit has a differential cylinder and a digital hydraulic controller with four rows of valve elements, two of which are, with their common controller output, connected to the one pressure chamber of the differential cylinder, while the other two rows of valve elements are, with their common controller output, connected to the other pressure chamber of the differential cylinder. The differential cylinder can be used as a precisely adjustable linear actuator.

Abstract: An electronically controlled valve includes a valve member moveable between a first position and a second position. A valve member moving mechanism is operable to receive energy from a fluid-working machine crankshaft, or other rotating shaft, and to provide a valve member moving force to urge the valve member from the first position to the second position using the received energy. Thus, the energy used for movement of the valve against a pressure gradient is derived from the crankshaft. Energy received from the crankshaft can be stored and used subsequently to urge the valve member from the first position, allowing the valve to function despite timing differences between the availability of energy from the crankshaft and the requirement for energy to move the valve member.

Abstract: The present invention provides a control method and a control apparatus for a vehicle that make it possible to moderate or completely eliminate the impacts generated when the bucket is operated in a tilt direction, from a state in which the bucket in a dump position is forcibly actuated in the tilt direction and the bucket hydraulic cylinder is pressurized by the lifting operation of the boom and also to perform the boom lifting operation with good operability and workability.

Abstract: An apparatus includes a first plurality of cylinders, each coupled to a shared first port by a separate first valve and to a shared second port by a separate second valve. Each first and second valve has a chamber to which pressure from either the associated cylinder or the respective port is dynamically applied to select different operating modes. Each one of a second plurality of cylinders is coupled to the first port by a separate third valve and to a shared third port by a separate fourth valve. Each third and fourth valve has a chamber to which pressure from either the associated cylinder or the respective port is dynamically applied to select different operating modes. Selecting an operating mode enables the apparatus to act as a bidirectional pump or a hydraulic motor. Selectively controller the valves can deactivate an individual cylinder, while other cylinders remain active.