Abstract: Disclosed is a fuel injection device comprising a housing and a valve element disposed therein and cooperating with a valve seat located in the area of at least one fuel discharge port. The valve element is composed of several parts while at least two parts of the valve element are coupled to each other via a hydraulic coupler.

Abstract: A valve assembly may include a body having an axis and a flow tube attached to the body for flowing a fluid therethrough, the flow tube having a first bend and a second bend. The valve assembly may further include a valve attached to the flow tube having an axle that is perpendicular to the axis, and a piston attached to the body and the axle and parallel to the axis.

Abstract: A device for dispensing a heated liquid, such as a hot melt adhesive, which includes a dispenser body adapted to dispense the heated liquid, a solenoid valve, and a pneumatic section including a housing coupled between the solenoid valve and dispenser body. The pneumatic housing is formed from a thermally insulating material which may include a thermoplastic polymer such as polyphenylene sulfide (PPS) or a fluoroplastic polymer to reduce heat transfer from the dispenser body through the pneumatic housing thereby thermally insulating the solenoid valve.

Abstract: The shut-off system according to the invention for large conduit cross-sections has a swing flap which can be swung to and fro between two end positions about a pivot axis by means of a drive device, wherein the drive device has a drive shaft which is connected to the swing flap via an elbow lever, and at least one lever arm rigidly connected to the drive shaft is provided which is in operative connection with at least one operating cylinder for rotation of the drive shaft. The drive device has a motion link which is fastened so as to be rotatable about a pivot bearing, wherein the operating cylinder is connected to the motion link to pivot the same, and a transmission element is provided between the lever arm and the motion link in order to transmit the pivoting motion of the motion link to the drive shaft.

Abstract: The present invention relates to a leveling valve including a first port, a second port, a third port, a valve, and a clutch. The clutch is provided with an engaged position and a disengaged position. At least a portion of the clutch may move relative to the valve when the clutch is in the disengaged position. The clutch moves the valve when the clutch is in the engaged position. The valve is movable between a first position, a second position, and a third position. When the valve is in the first position, the valve blocks a first pathway, which extends from the first port, from connecting with a second pathway, which extends from the second port. When the valve is in the second position, the valve allows the first pathway to connect with the second pathway. When the valve is in the third position, the valve allows the second pathway to connect with a third pathway, which extends from the third port.

Abstract: The invention concerns pneumatic actuators for valves comprising a body closed by head flanges, two pistons moving in said body in opposite directions, an output shaft that turns actuated by the pistons, and a stop device on each head flange to limit the stroke of the pistons when they move away from each other towards the head flanges. On at least one side of the actuator body an adjusting device (22) is provided which includes stop means (26, 27) at varying distances from each other in a direction parallel to the movement of the pistons and arranged in a position to intercept and limit the stroke of the pistons when the latter move towards each other.

Abstract: A pressure relief valve includes a lever plate, a first spring, a fitting, and a guide assembly. The fitting has a first side, a second side, and a flange having a rounded end and includes a surface with which a first end of the first spring contacts. The guide assembly has two sides, two concavities, and at least a portion of the guide assembly extends through the opening of the lever plate, the first concavity is formed on the first side of the guide assembly and contacts the fitting flange rounded end, and the second concavity is aligned coaxially with the first concavity. A rounded end of a rod of the diaphragm assembly contacts the second concavity. The second spring is adapted to supply a second force against the diaphragm assembly to move the lever plate in a second direction that is substantially opposite the first direction.

Abstract: A valve actuator assembly, counter-biased by a working fluid (or gas) pressure, is disclosed. The valve actuator assembly comprises a valve and a pneumatic or hydraulic actuator. A port is defined axially through the valve and actuator that communicates a working fluid (or gas) pressure acting on the valve face to a counter-biasing chamber inside an actuator housing. This design eliminates, reduces, or overcomes a force acting on a face of the valve by communicating a common working pressure of the fluid (or gas) to a substrate on the actuator with a resultant force vector opposite the valve face.

Abstract: An actuator comprising a cylinder and a spring return piston provided with linkage means, in which one or more return springs are situated on the same side of the piston as the linkage means.

Abstract: The disclosure relates to a method for commissioning pneumatically operated actuators that are controlled by a positioner. To determine the drive type, a constant flow of pneumatic fluid is applied to the actuator during commissioning while a drive-specific characteristic curve of the fed back position is recorded over time. Then the measured characteristic curve is compared with a given specimen characteristic curve. The drive type is inferred from the level of difference or agreement between the drive-specific characteristic curve and the specimen characteristic curve.

Abstract: A device for dispensing a heated liquid, such as a hot melt adhesive, which includes a dispenser body adapted to dispense the heated liquid, a solenoid valve, and a pneumatic section including a housing coupled between the solenoid valve and dispenser body. The pneumatic housing is formed from a thermally insulating material which may include a thermoplastic polymer such as polyphenylene sulfide (PPS) or a fluoroplastic polymer to reduce heat transfer from the dispenser body through the pneumatic housing thereby thermally insulating the solenoid valve.

Abstract: Hydraulic actuating device (1) for actuating a water evacuation mechanism (2), includes: an actuating unit (4) with plunger(s), a control unit (5) that can be integrated with the actuating unit, at least one three-way hydraulic valve (6) supplied by a water distribution system and controlled by the control unit (5), and at least one single-action hydraulic jack (3) supplied via the valve and ensuring the triggering of the water evacuation mechanism by raising a closing flap (56) or a plug.

Abstract: A pressure-reducing valve is provided in which a diaphragm rod connected to a valve body of a valve mechanism is connected to a central part of a diaphragm having its peripheral edge part clamped between a body and a diaphragm cover, wherein the diaphragm (28) is formed from a disk-shaped rubber sheet for which the sheet thickness of at least its peripheral edge part is uniform in the natural state, and in a state in which the diaphragm cover (17) is fixed to the body (16) so that the peripheral edge part of the diaphragm (28) is compressively held between a collar portion (17b) of the diaphragm cover (17) and a clamping face (91) of the body (16), a portion having, of the gap between the collar portion (17b) and the clamping face (91), a minimum gap is positioned further inward in the radial direction of the diaphragm (28) than a portion having a maximum gap.

Abstract: A tap adapter comprises a tap head, a tap body and a plunger. The plunger is mounted within the body so as to be movable from a closed position to both a first open position and a second open position. Resilient means are arranged to return the plunger from either open position to said closed position. The adapter is arranged such that the return to the closed position from said first and second open positions takes different lengths of time.

Abstract: An adaptor for a water delivery device to avoid water wastage by the provision of two durations of water flow, comprising a tap head, a tap body and a plunger, the plunger being slidably mounted within the body so as to be movable from a closed position to both a first open position and a second open position; resilient means being arranged to return the plunger from either open position to said closed position, the adapter being arranged such that the return to the closed position from said first and second open positions takes different lengths of time, and adjustment means arranged to adjust the ratio between the length of time for the plunger to return to the closed position from the first open position and the length of time for the plunger to return to the closed position from the second open position.

Abstract: The present application relates to an arrangement for selectively providing a plurality of output forces, such as for example, a higher and a lower output force or a predetermined, time dependent output force. In one embodiment, a first piston assembly is moveable between a first and a second position and a second piston assembly moveable between a third and a fourth position. When the first piston assembly is in the first position, the second piston assembly is selectively movable between the third position and the fourth position. When the first piston assembly moves the second position, it moves the second piston assembly to the fourth position.

Abstract: A valve actuator comprises a housing, a lever, and a positioning device.

Abstract: A dispenser includes an actuating section having a first moveable member and a hydraulic section coupled with the actuating section and having a second moveable member. The hydraulic section is adapted to dispense a liquid from an outlet therein and the actuating section is adapted to control dispensing of the liquid. An actuator assembly operatively couples the first moveable member with the second moveable such that the first moveable member is operative to move the second moveable member between open and closed positions for respectively starting and stopping flow of liquid from the outlet. The actuator assembly may include a pivoting lever arm having a first end operatively coupled with the first moveable member, a second end operatively coupled with the second moveable member and defining a fixed pivot point therebetween.

Abstract: A controller comprises power transmitting means (11) for amplifying the force applied on the operating shaft (6) and transmitting to the valve rod (4); and a slow start means (12) for slowly moving the operating shaft (6) upward are arranged.

Abstract: A valve actuator comprises a housing, a lever, a collet, and a biasing device. The lever is disposed within the housing and is adapted to be operatively coupled to rotate the valve shaft. The collet is carried by the lever and adapted to couple the lever to the valve shaft. The biasing device comprising a spring operatively coupled to the collet to bias the lever into a predetermined position.

Abstract: A diaphragm controlled bypass valve includes a diaphragm valve portion and a needle valve portion. The diaphragm valve portion regulates pressurized gas supplied from a pump to determine whether or not to open or close a needle valve. The needle valve portion includes an inlet port, an outlet port and a flow pathway defined between the inlet and outlet ports. A needle pin is disposed within the flow pathway and is coupled to a diaphragm positioned within the diaphragm valve portion. When the diaphragm is displaced in response to changes in pressure, the needle valve pin is likewise displaced which opens and closes the flow pathway.

Abstract: A valve assembly includes a valve body having an inlet port and an outlet port, the valve body also having a valve chamber extending between the inlet port and the outlet port, a pair of seals each being located on opposing ends of the valve chamber; and a reciprocating piston extending into the valve chamber and movable between a closed position extending through the pair of seals and an open position extending only through one of the pair of seals, wherein the inlet port is fluidly connected with the outlet port when the piston is in the open position. A method of using the valve assembly is also disclosed.

Abstract: A pneumatic valve with lockout for controlling the flow of a fluid includes a housing, a fluid flow passage extending through the housing between a fluid inlet and a fluid outlet, and a valve movable along an axis to open and close the flow passage. A pneumatic actuator is operable to move the valve to open and close the flow passage. A manual lockout device is actuable to selectively enable and actuation of disable the valve. The device includes a locking member movable to prevent the lockout device when the valve is disabled. A fitting on the housing to convey a pressurized gas to the pneumatic actuator is mounted to swivel about the housing for connection to an air source on any radial within 360°. The valve is compact, simple to connect in a system and safe.

Abstract: The present invention provides a valve actuator for a valve that includes a cylindrical body that is thermally nonconductive and configured to engage a valve stem. A cylindrical adjuster is positioned coaxially with the body. A shaft extends through the adjuster and the adjuster is axially movable between a first position and a second position such that when the adjuster is in the first position a first engaging means engages a second engaging means thereby fixing the position of the adjuster relative to the body. When the adjuster is in the second position the adjuster is radially movable relative to the body. A spring is aligned with the shaft and configured to bias the adjuster toward the first position such that the first engaging means engages the second engaging means thereby fixing the position of the adjuster relative to the body.

Abstract: An actuator assembly including an actuator housing assembly having a linear drive mechanism disposed at least partially therein. A linear variable differential transducer (LVDT) is coupled to the linear drive mechanism and configured to eliminate rotation of the linear drive mechanism and provide linear positioning of the linear drive mechanism. A valve shaft is coupled to the linear drive mechanism and in substantially linear alignment with the linear drive mechanism. A rotational coupler, in the form of a helical groove and reciprocating guide member, is formed to couple the linear drive mechanism to the valve shaft. The valve shaft is configured to allow for the linear displacement therein of the linear drive mechanism and thereby output a rotation moment via the rotational coupler to the valve shaft.

Abstract: There is disclosed an actuator for delivering a supplementary force to the piston of a shear ram in a blowout preventer (BOP), and a corresponding BOP. In one embodiment, a supplementary force actuator (12) is disclosed for use on a hydraulic ram (10), the actuator comprising an actuator body (30) connected to the hydraulic ram; first and second chambers (38, 36) located in the body, the chambers isolated from each other by an actuator piston (46); a rod (42) connected to an operating piston (24) of the hydraulic ram, passing through the first chamber and the actuator piston, and extending into at least a portion of the second chamber; wherein the actuator piston is releasably engageable to the rod by gripping means (48); and wherein the hydraulic ram is operated by a force from movement of the operating piston and by a supplementary force from movement of the actuator piston.

Abstract: A combined actuator provided with: a mobile element; a driver for displacing the mobile element; and a rheological control brake, which is mechanically coupled to the mobile element to adjust the displacement of the mobile element; the rheological control brake has: two contiguous adjustment chambers; a rheological fluid contained in the two adjustment chambers; a sliding piston, which tightly separates the two adjustment chambers and is mechanically connected to the mobile element; at least one external connection pipe, which reciprocally connects the two adjustment chambers; and a driving device which is coupled to the external connection pipe so as to apply a variable electromagnetic field to the rheological fluid contained in the external connection pipe for varying the viscosity of the rheological fluid between a minimum value and a maximum value.

Abstract: An improved one-way fluid valve construction is provided. A valve housing (102) includes one or more valve ports (108) and control ports (110). A control member (304) is disposed within the control port (110). The control member (304) is movable within the control port (110) between a first position and a second position. A control rod (302) can extend between the control member (304) and a portion of the valve port (108). A control rod coupling (402) interacts with the control member (304) to cause a rotational or pivotal movement the control rod (302) through a predetermined angular arc in response to movement of the control member (304). A sealing face (404) formed on a second portion of the control rod (302) advantageously forms a seal with an orifice (316) that separates an input side of the valve port (108) from an output side. The seal can be formed when the control rod (302) is in a control rod sealed position.

Abstract: A bearing mounted ball valve (10) comprises a housing (12) having a throughbore and a valve seat (16) and an apertured ball (18) mounted within the housing in continuous engagement with the valve seat. The apertured ball is rotatable by rotation means (20), about an axis of rotation, between a throughbore open position and a throughbore closed position. The bearing mounted ball valve further comprises bearing means (26) coupled between the apertured ball and the housing for constraining the rotation of the apertured ball about the axis of rotation between the throughbore open and the throughbore closed position. In the throughbore closed position, the bearing means is adapted to release the apertured ball from the axis of rotation to permit the apertured ball to float into a sealing engagement with the valve seat.

Abstract: A fluid control device or a device for coupling a rotary valve actuator to a rotary valve shaft comprises a housing, a lever, a threaded collet, and first and second stops carried by the housing. The lever comprises a cylindrical member containing the threaded collet. During operation, the first and second stops limit the rotation of the lever between first and second positions, thereby limiting rotation of the valve shaft. During assembly, the device further comprises a third stop that is removably carried by the housing. The third stop engages the lever in the first position simultaneously with the first stop, for example, thereby locking the lever against rotation. With the lever locked, a technician may apply generally any amount of torque to a draw nut disposed on the collet to tighten and/or loosen the collet onto the rotary valve shaft without rotating the lever.

Abstract: A diaphragm valve for use in an irrigation system is disclosed that is adapted to reduce the water hammer effect, reduce debris in a flow path through a valve seat, improve bleed operation and/or reduce manufacturing and materials costs.

Abstract: The invention concerns a hydraulic valve arrangement (1) with several valve modules (2-6), each having a supply channel arrangement with a high-pressure channel (7) and a low-pressure channel (8), a working connection arrangement with at least one working connection (A, B), a directional valve arrangement (15, 16) between the supply channel arrangement and the working connection arrangement and a compensation arrangement (19, 28). It is endeavoured to improve the control possibilities. For this purpose, it is provided that in at least one valve module (3, 5) the compensation arrangement is a pre-compensation arrangement (19) and in at least one other valve module (4, 6) the compensation arrangement is a post-compensation arrangement (28).

Abstract: The invention relates to the field of the submarine valve actuators, and specifically to those actuators, that in order to effect a standard valve closing operation are connected to an oleo system feeding an hydraulic cylinder (1), whose plunger (3), by a mechanical link, operates the valve and compresses a spring (8) which provides for the standard opening operation. Said actuators are provided with an input shaft (21) for connectin a ROV for valve opening and closing operations when there is a failure in the oleo system. The connection between the ROV-operated input shaft (21) and the mechanical link between the piston (3) and the spring (8) is carried out by a planetary gear reducer (15).

Abstract: A locking assembly is provided to simply and effectively prevent any unintentional adjustment of the adjustable valve mechanism in a fluid flow control device, without compromising the function of the device. The locking assembly generally includes at least one gripping arm for frictionally engaging at least a portion of the adjustable valve mechanism, and an actuating mechanism for controlling the deployment and release of the gripping arm. The locking assembly prevents unintentional adjustments that can adversely affect the pressure settings of the fluid flow control device. In particular, the locking assembly prevents unintentional adjustment, such as may be caused by the presence of a strong external magnetic field. The locking assembly can be easily disengaged, such as through the application or removal of an external mechanical force, to allow a clinician to adjust the pressure settings of the fluid flow control device as necessary.

Abstract: A valve arrangement includes a spool movable in first and second strokes. A first biasing member has a first spring constant and a first preload, and a second biasing member has a second spring constant lower than the first spring constant and a second preload higher than the first preload. The first biasing member and not the second biasing member biases the spool toward the center position through the entire first stroke and during movement of the spool from a center position to an intermediate position within the second stroke. The first and second biasing members act in series to bias the spool toward the center position during movement of the spool from the intermediate position to an end of the second stroke.

Abstract: A valve actuator comprises a housing, a lever, a collet and a biasing device. The lever is disposed within the housing and is adapted to be operatively coupled to rotate the valve shaft. The collet is carried by the lever and adapted to couple the lever to the valve shaft. The biasing device comprising a spring operatively coupled to the collet to bias the lever into a predetermined position.

Abstract: A multifunctional regulator provides a housing having an inlet passage joined with an outlet passage through a poppet valve. The housing has a control diaphragm separating the control chamber into a first volume and a second volume and depending on the differential pressure between the two volumes, the diaphragm will push open the poppet valve. Pressurizing and depressurizing valves join the first volume with the inlet and outlet passages, whereby, with an inlet pressure level within the inlet passage greater than an outlet pressure level within the outlet passage, and with the pressurizing valve admitting the inlet pressure level to the first volume, the diaphragm is displaced into the second volume thereby forcing the poppet valve to open and thereby raising the outlet pressure toward the inlet pressure with fluid flow from the inlet to outlet passages.

Abstract: Force amplifying means 5 comprises a tapered member 41 extending vertically downward from the lower end of an operating rod 3, a disk member 42 provided at the upper end of a valve stem 16, and front and rear pivotal members 43, 44 arranged between the two members 41, 42 and opposed to each other with the tapered member 41 positioned therebetween, the pivotal members 43, 44 being pivotally movable about respective pivots 45, 46. Each of the pivotal members 43, 44 has a plate body 43a, 44a, an upper contact face 43b, 44b formed on an upper portion of the body and in bearing contact with a tapered face of the tapered member 41, and a lower contact face 43c, 44c formed on a lower portion of the body and bearing on the upper surface of the disk member 42. The lower contact face 43c, 44c of each pivotal member is in the form of a circular-arc cam face centered about a center line positioned away from the axis of the pivot 45, 46.

Abstract: A valve actuator comprising a lower housing comprising a mounting spool that is operable to couple to a valve body. A rotating sleeve is disposed within the lower housing and coupled to a stem connector. A fixed sleeve in disposed within the lower housing and includes a first slot disposed therethrough. A second slot is disposed in the rotating sleeve, wherein at least one of the slots is a helical slot. An axle engages both the first slot and the second slot. A shaft is coupled to the axle and extends through a connector flange that is coupled to an upper end of the lower housing. A piston is coupled to the shaft and movably disposed within an upper housing that is coupled to the connector flange. Axial movement of the piston within the upper housing will result in rotational movement of the rotating sleeve.

Abstract: The present invention is a method where a one-piece throttle valve is fastened to a throttle valve shaft in a first step. In another step, at least one elastic compensating element is placed onto the throttle valve. In another step, the elastic compensating element is pressed against the inner wall of the throttle valve housing by an expanding tool. In another step, the elastic compensating element pressed against the inner wall of the throttle valve housing is joined to the throttle valve.

Abstract: An actuator (16) for a rotor valve (10). The actuator includes a rack (86) for driving a pinion gear (87) of the valve. The rack is moved between first and second positions by the action of a first piston (88). Movement of the first piston and rack is selectively restricted in one direction by the movement of a moveable stop (104) from a withdrawn position to an extended position, thereby defining a third position of the rack. The moveable stop may be driven by a second piston (102). The first and second pistons may be powered by a common compressed air supply (122). The cross-sectional area of the first piston may be at least 1.4 times the cross-sectional area of the second piston to ensure that the force exerted by the first piston is not sufficient to displace the moveable stop from the extended position when the second piston is open to the compressed air supply.

Abstract: A valve assembly for controlling flow of cryogenic fluids is disclosed. In an embodiment, the valve assembly includes a valve housing and a valve member supported at the valve housing for movement between a valve opened and a valve closing position. A pneumatic cylinder is disposed laterally spaced from the valve member and thermally isolated with respect to cryogenic fluids controlled by the valve member. A lever operatively connects the pneumatic cylinder with the valve member and a linkage is pivotally connected with the lever at a position spaced from the valve member. The valve member is a needle valve member supported for axial movement at the housing.

Abstract: A valve, actuator and control system that allows minimizing the size of the actuator and operation of the control system in a manual mode that automatically prevents accidental operation by pipeline pressure is disclosed. The actuator uses gas pressure from the pipeline to power the actuator. In the event gas pressure is unavailable, a pair of manual hand pumps are incorporated to allow operation of the actuator and valve.

Abstract: The invention is therefore directed to a rotary valve actuating system coupled to a pipeline for a pressurized fluid, the actuating system being coupled to the rotary valve to selectively cause operation of the valve. The valve actuating system comprises at least two reservoirs having an amount of an operating liquid in a first portion being coupled to an external source of pressurized fluid in a second portion thereof. A slideable piston is positioned within each of the reservoirs to isolate the first and second portions, and upon application of pressure from the external pressurized fluid against the slideable piston, operating liquid is supplied to actuate the rotary valve. In this manner, the operating liquid is isolated from the external source of pressurized fluid, such as supplied from the pipeline.

Abstract: A pipeline isolating device for istallation into and occlusion of a pressurised liquid or fluid supply pipe comprising a substantially solid and deformable boot (1) wich is adapted to move between an expanded and an unexpanded state and a shaped plunger (2) adapted to move into and out of said boot (1) wherein the boot (1) has a hollow interior (3) with a displacement contour (6) adapted to receive and cooperate with said plunger (2) so as to cause said boot (1) to move between said expanded state when the plunger (2) is inserted into said hollow interior (3) of the boot (1) and said unexpanded state when said plunger (2) is withdrawn from the interior (3) of the boot (1).

Abstract: A servomechanism for a valve controlling engine intake flow via a cooler and a bypass uses a proportional solenoid operating a hydraulic valve to power a hydraulic actuator setting the position of the control valve. An engine sensor and electric controller provide input to the proportional solenoid, and feedback from the position of the control valve is applied to the hydraulic valve by a cam and spring applying a force in opposition to the proportional solenoid.

Abstract: An electrohydraulic valve actuator assembly for an engine includes a movable engine valve, a movable spool valve, and a driving channel interconnecting the spool valve and the engine valve. The electrohydraulic valve actuator assembly includes an actuator operatively cooperating with the spool valve to position the spool valve to prevent and allow fluid flow in and out of the driving channel to position the engine valve. The electrohydraulic valve actuator assembly further includes a mechanical feedback interconnecting the engine valve and the spool valve to control the position of the spool valve.

Abstract: A pressure relief system is provided to detect and abate an overpressure condition in a pressurized fluid disposed in a conduit. The system includes a valve assembly and an actuator configured to actuate the valve assembly to establish an overpressure path for the pressurized fluid. The system further includes a piston assembly coupled to the conduit, a pressure responsive member (preferably a collapsible buckling pin) configured to mechanically fail when an axially directed compressive force exceeds a threshold level, and a multi-port, two-position valve disposed between the piston assembly and the pressure responsive member. The multi-port, two-position valve includes a spool that moves from a first position to a second position upon failure of the pressure responsive member, thereby directing control fluid through the spool to the actuator assembly.

Abstract: The present invention includes a disc drive shocker having a fast valve which can be moved from a full on position to a full off position within a desired interval of time to impart a shock to a disc drive. The valve is connected to a valve actuator which moves the valve spool within the valve housing. The valve actuator is connected to the valve spool though a lever. The lever is pivotable about a fulcrum. The pivot point of the fulcrum is adjusted, away from center, such that the end of the lever connected to the valve spool moves more quickly than the end of the lever connected to the valve actuator.

Abstract: A fluid control valve for a pipeline pig includes a main valve and a mechanism for operating the main valve. The main valve comprises a valve body communicated to a fluid pipe, a main valve core movably disposed in the inner chamber of the valve body, and a main valve stem connected to the main valve core. The operating mechanism includes a hydrocylinder, which comprises a piston disposed in the cylinder, and a piston rod connected to the piston. The piston rod is transmissibly connected with the main valve stem so as to drive the main valve core by the main valve stem. A valve device includes a pilot valve, positioned in the pipeline which communicates the fluid pipe with the hydrocylinder, and an operator for controlling the actuation of the pilot valve so as to enable the piston to move reciprocally by the pressure of fluid in the fluid pipe.