Abstract: An air duster structure that is configured to jet compressed air out of a nozzle, includes a flow amount adjustment mechanism which is configured to adjust an amount of air jetted out of the nozzle. The flow amount adjustment mechanism includes: a pipe line for circulating air; a valve member disposed inside the pipe line and being movable; and a throttle portion configured to gradually change an area of a flow channel in which air circulates, with a movement of the valve member, to control a flow amount of the air in the pipe line. The throttle portion is structured so as to increase the area of the flow channel at an accelerated rate when the valve member moves in a direction that opens the pipe line.

Abstract: A pneumatic brake system that includes at least one pneumatic latching valve; a single device, such as a solenoid, for providing momentary pilot signals to pneumatic latching valve; a source of pressurized supply air in communication with the pneumatic latching valve; a spring brake or other pneumatic device in communication with the pneumatic latching valve; and, optionally, an indicator device for monitoring and displaying the state of the pneumatic latching valve. Upon receiving a first momentary pilot signal the pneumatic latching valve changes from closed to open and delivers pressurized air to the spring brake. Upon receiving a second momentary pilot signal, the pneumatic latching valve changes from open to closed and exhausts pressurized air from the spring brake to the external environment. The valve remains “latched” in its current state until the signaling device is energized and the next momentary pilot signal is received.

Abstract: The invention relates to a remote controller for heavy construction machines with a body, comprising a cavity, running between a first outlet end and a base, a first pushrod, running between a head and a base, arranged to slide with a back and forth movement in the cavity along an axial direction, a handle which may pivot with relation to the body, whereby a skirt of said handle is in direct contact with the head. The first pushrod may furthermore be moved to an extended position opposite to the depressed position with relation to the idle position thereof. First elastic return means are arranged in the cavity to force the pushrod into the extended position thereof and detection means are provided to detect the position of the first pushrod.

Abstract: A control circuit for an attachment mounting device that has a closed position for securing an implement and an opened position for releasing an implement. The control circuit includes at least one hydraulic actuator, a control valve and an auto-close feature. The control valve has at least a first energized position and a second energized position. The first energized position applies pressurized fluid to the at least one hydraulic actuator to actuate the attachment mounting device into the closed position. The second energized position applies pressurized fluid to the at least one hydraulic actuator to actuate the attachment mounting device into the opened position. The auto-close feature is configured to be activated after the control valve is in the first energized position and is configured to be deactivated after the control valve is in the second energized position.

Abstract: The invention concerns a fluid distributor, in particular a hydraulic manipulator comprising a body (5), a pressure reducing valve (2) mounted in the body comprising a plunger (3) mobile in translation and whereof the displacement is controlled by a push-rod (11), a control member (6) including at least one finger (10) for modifying the position of the push-rod, means forming a solenoid (15) mounted in the body, a frame (16) adapted to be driven in translation simultaneously with the push-rod. The dispenser further comprises means for catching (20) the frame on the finger delimiting a window wherein the finger projects substantially transversely, the push-rod being mounted so as to pass right through the frame and project into the window, and the finger being interposed between the catching means and the push-rod.

Abstract: A valve assembly for an air pressure system includes an inlet valve, a first control valve, and a second control valve. The inlet valve includes an inlet port, an outlet port and a control port. The inlet valve inlet port communicates with the inlet valve outlet port when the inlet valve control port is above a threshold pressure. The first control valve includes an inlet port, an outlet port, an exhaust port, and a control member. The first control valve inlet port communicates with the inlet valve outlet port. The first control valve outlet port communicates with one of the first control valve inlet port and the first control valve exhaust port as a function of a position of the first control valve control member. The second control valve includes an inlet port, an outlet port, an exhaust port, and a control member. The second control valve inlet port communicates with the inlet valve outlet port.

Abstract: For a valve arrangement of a pneumatically actuated, spring-loaded control cylinder, a non-return valve in pneumatic communication with the control cylinder piston chamber. At very low backpressures in the control cylinder piston chamber caused by leaks of the valve responsible for pressurization of the piston chamber, the chamber is vented by passage of a very small air stream via the non-return valve. In this way, leaks cannot cause a very slow pressure buildup in the control cylinder piston chamber, followed at some time by undesired shifting of the control cylinder. In contrast, in the case of normal pressure buildup, i.e., during switching of the pressurizing valve, the non-return valve is promptly closed and the pressure in the control cylinder piston chamber is not influenced.

Abstract: A seated-type valve S provided for the double-acted cylinder Z of an electric disconnector TS, comprises a housing G containing a slider closure element 7 and a separating actuating force generator C1 and a switch-on actuating force generator C2 for the slider closure element 7, respectively. At least the separating actuating force generator C1 is equipped with a piston D1 contained in an interior bore 23 of the slider closure element 7, which piston D1 abuts in the housing G without generating lateral forces for the slider element 7.

Abstract: A braking system control requires that a first or service braking system be actuated before a second or parking braking system can be released to prevent unexpected movements. A sensor senses that the service brakes are engaged and controls a device to release the parking brakes. A latch ensures that the parking brakes remain released. For example, a piston and check valve form the sensor and latch. Service brake pressure works against the piston. Above a threshold level, service brake pressure drives the piston to open a valve that provides pressurized air to a parking brake release system. Once released, the check valve directs parking brake release pressure to the piston to keep the valve open.

Abstract: A spool valve may be used in a subsea system with a single upstream pilot valve to control the spool valve. The spool valve opens and closes a main valve in response to fluid signals from the pilot valve. The main valve is connected to a source of pressurized supply fluid, which is selectively directed to a downstream apparatus. The spool valve and the main valve can be produced in an integrated design with a single body. In an alternative embodiment, the spool valve and main valve are separate with separate bodies. The spool valve may also be used in non-subsea systems.

Abstract: A hydraulic latching spool valve has at movable piston and valve cage defining two seats. In the valve cage, a moveable piston is operable to move the valve into open and closed positions. A spring positioned in a pilot close chamber urges the piston to close. A pulse of fluid pressure at a pilot open chamber causes the piston to open. A latching chamber is formed on the interior of the piston, the latching chamber being exposed to supply pressure when the piston is in the open position. Accordingly, in the open position, supply fluid in the latching chamber generates sufficient latching force to overcome opposing forces generated by the sprig. The supply pressure holds the piston in the open position until a pulse of fluid pressure is applied to the pilot close chamber, thereby causing the valve to close.

Abstract: Governor valve device for a pressure fluid operated tool having a ball valve (23, 24), the valve ball (24) of which is provided in a cavity (25), open towards the seal ring (23) of the valve, in a movable piston (26). A spring-loaded member (30) urges the valve ball against the seal ring. By movement of the piston, the ball can be moved out of and into, respectively, a sealing position against the seal ring in order to permit and to prevent, respectively, the passage of pressure fluid to a drive chamber (17) in the tool.

Abstract: The normally closed, two-position, three-way latching hydroseal valve can be used in subsea applications in connection with the production of oil and natural gas. The latching hydroseal valve can be operated by remote pilot valves to open and close the latching hydroseal valve or in an alternative embodiment attached solenoid pilot valves can be used. The seal carrier has pistons of different diameters to latch the valve open after the pilot fluid is vented to atmosphere. The main seal assembly includes a bi-directional seal.

Abstract: A directional control valve comprises a spool which is movable in a chamber and which carries shear seals urged against a respective wall of the chamber, the spool being movable between a first position in which a fluid supply inlet is in communication with a functional outlet and a second position in which the fluid supply inlet is cut off from the functional outlet, and a safety piston which is spring-loaded towards engagement with the spool in a sense to move the spool to the second position. An intermediate piston is interposed between the spool and the safety piston so that the intermediate piston can allow relative movement between itself and the spool. The chamber includes a port coupled to a pressure transducer which can monitor the position of the valve spool or the function line pressure.

Abstract: A directional control valve has snap-locking device for retaining the slide of the directional control valve in at least one switching position. The snap-locking device has a snap-locking part with a snap-locking piston that allows an engagement part to engage and lock the slide of the directional control valve. A kick-out device disengages the engagement part when a predetermined control pressure is exceeded. The kick-out device triggering force may be adjusted by a setting device that acts on a kick-out spring. A switching device that allows the kick-out function to be switched off independently of the setting of the setting device associated with the directional control valve in order to prevent disengagement independently of the initial stress of the kick-out spring.

Abstract: A power transmission has a plurality of shift valves each of which has an engaged position and a disengaged position. Each shift valve has a pair of chambers which is selectively pressurized by a latching valve to maintain the shift valves in their respective selected positions. During a ratio change, the latching valve discontinues pressure at the respective shift valve chambers to permit the appropriate shift valve movement.

Abstract: In a hydraulic control system including a valve device B for controlling a hydraulic fluid supplied from a hydraulic pump A to a hydraulic cylinder C, the valve device comprises a spool 16 slidably fitted into a valve body 1, and a non-leak valve 27 for controlling communication of an actuator passage 19. The non-leak valve comprises a main valve section 40 including a seat valve 41 provided in the valve body, and a pilot control section 60 including a pilot poppet valve 61 provided in an end cover 31. The seat valve is controlled in proportion to an opening of the pilot poppet valve, and a relief valve 55 for preventing the hydraulic cylinder from being subject to an overload is built in the seat valve. The non-leak valve thus fulfills a load holding function and an overload relief function. By arranging the non-leak valve and the spool in two lines, the valve device can be made more compact.

Abstract: A hydraulic pilot valve, including a plurality of pressure reduction valve portions, each having an inlet port, an outlet port and a pressure regulating valve for establishing and blocking communication between both ports by movement of the pressure regulating valve, a plurality of pistons actuating the pressure regulating valves of the pressure reduction valve portions in the direction establishing communication, an operation lever having a pushing member pushing the plurality of pistons, and springs for biasing the pistons upwardly beyond a neutral position to retain them in an abutting relation with a pushing member. An operating lever is rocked from the neutral position in one direction to place the lever in an actuating position and push one piston to place one of the pressure reduction valve portions in a pressurized fluid supply condition to establish communication between the inlet portion and the outlet portion.

Abstract: An input apparatus capable of concurrently accommodating itself to any external signal from a different hydraulic control system or the like. The apparatus includes electrical load sensors each arranged on a push rod or block for detecting the amount of operation of a control lever to generate an electrical signal corresponding to the amount of operation of the control lever. Also, an input apparatus which is capable of concurrently responding to both a signal generated by itself and an external signal fed thereto is provided. The apparatus includes a pilot section for exerting force which permits a shuttle to be moved against coiled compression springs. The pilot section is fed with a signal from an external hydraulic control system.

Abstract: A connector 5 having an outlet 4 for delivering a pressure oil to a power steering apparatus PS is secured in an opening of a valve receiving bore 2 in which a flow controlling spool valve 3 is received. The connector 5 includes an axial bore 5a which continues from the outlet 4 and in which a valve sleeve 10 is slidably fitted. The valve sleeve 10 has pressure oil passages 11, 12 therein in which orifices 13, 14, 15 are formed, and pressure differentials thereacross are utilized to operate the spool valve 3 in order to return an excess amount of flow. At its outer end, the valve sleeve 10 is formed with a flange 10b, and a restriction 20 is defined between the outer peripheral surface of the flange 10b and the internal peripheral surface of the valve receiving bore 2 for restricting the flow rate of the pressure oil. A pressure differential developed across the restriction 20 is effective to move the valve sleeve 10 to control the orifices 14, 15 so that the latter may be reduced.

Abstract: In a control device (S) for a hydraulic motor (V) which is adapted to be ed upon at both sides, there are provided working conduits (4, 5) which are alternately connectable via a directional control valve (C) to a pressure source (P) and a tank (T), a load holding valve (H) which is hydraulically openable in a controlled way and is arranged in at least one working conduit (4), as well as a control pressure conduit (13) which is connected to the opening side (16) of said load holding valve (H), with pressure variations arising during the controlled opening of the load holding valve, and the amplitudes of the pressure variations being adapted to be dampened in the control pressure conduit (13) at least via a damping throttle (D).

Abstract: A transmission control system includes a plurality of hydraulic pressure operated control elements for engaging a gear of the transmission in response to actuation of a shift control lever having neutral and non-neutral positions, a plurality of control valves for controlling pressurization of the control elements and a pump for supplying pressurized fluid to the control valves. An engagement override system includes a switch which is coupled to the shift lever and which energizes a solenoid when the shift lever is in its neutral position and de-energizes the solenoid when the shift lever is in its non-neutral position. In a preferred embodiment, an engagement override valve includes a pilot operated valve which controls communication between the pump, a reservoir and the pressure operated control elements. The solenoid controls the pilot operated valve.

Abstract: In a hydraulic control device (S) comprising a double-acting hydraulic consumer (V) which is actuable by pressure via two working conduits (4, 5) and secured in at least one working direction by a load holding valve (H) which is hydraulically openable and closable in a controlled way, further comprising a control pressure conduit (12) which is connected to a control connection of the load holding valve and selectively actuable, as well as a damping throttle (13) arranged in control pressure conduit (12), there is provided a valve (15, 15', 15", 15'", 15.sup.IV) which during the controlled closing movement of load holding valve (H, 6) is automatically responsive to a delay of the controlled closing movement which is caused by the instantaneous viscosity of the pressure medium and/or a too tight setting of damping throttle (13) and is critical as to the after-running of hydraulic consumer (V) under a load (F), with the valve switching in such a case to passage and bypassing damping throttle (13).

Abstract: An improved pneumatic control system is selectively deactuable and actuable for controlling movement of the armature of a pneumatically-operated device between first and second working positions and includes a timing subsystem that enhances the efficiency of the overall system by stabilizing the control system at a pressure necessary to maintain certain static conditions in the pneumatically-operated device, while still providing for full control air pressure when dynamic operations are required. In addition, such a control system compensates for system leakage in an efficient manner by using full control air pressure only when needed for proper operating functions of the overall system.

Abstract: A pneumatic percussion tool includes a head valve device including first and second head valves disposed in the body and movable in response to the pressure variation in the head valve chamber. The first and second head valves are positioned at a first position for preventing communication between the main air chamber and the percussion piston chamber while permitting communication between the percussion piston chamber and the outside of the body and preventing communication between the head valve chamber and the outside of the body when the compressed air is introduced into the head valve chamber through the change-over valve.

Abstract: A control valve includes a main valve spool movable to a plurality of positions. A detent mechanism with a plurality of operational modes operates to releasably hold the main valve spool in displaced positions. An operator-controlled selector mechanism is coupled to the detent mechanism and is operable to selectively place the detent mechanism in a selected one of its operational modes.

Abstract: A hydraulic system includes a multi-position valve which controls the flow of system fluid pressure to various work stations. The multi-position valve is biased by a centering spring to a neutral position from which it can be shifted to a selected working position. A retaining mechanism is able to retain the valve in the selected working position when the system pressure is in a prescribed pressure range. The retaining mechanism is urged to its retaining position by a control fluid pressure which is derived from the system pressure. When the system pressure is below or above the prescribed pressure range the retaining mechanism is unable to resist the force of the centering spring and the valve assumes a neutral position. When the system pressure is in the prescribed range, a constant control pressure is supplied to the retaining mechanism for effectively resisting the force of the centering spring.

Abstract: A bistable slide valve 10 (FIG. 1) has a slide member 12 moved between operating positions by short control fluid pulses and has a safety shut-off for supply pressure failure in the form of safety spring 38 opposed by valve supply liquid in line 22 acting on a safety piston 37. Slide member 12 has a through-aperture 29 connecting supply and function lines 22, 23 when the valve is open and venting the function line via slide chamber 12 to return line 24 when the slide member is displaced. Safety shut off, less dependent upon indeterminate frictional resistance of the slide member, is achieved by a stronger safety spring and greater liquid-derived restraining force so that the frictional resistance force is a small proportion of the total restraining force, with smaller variations in residual pressure at which the safety means operates.

Abstract: A piloted rotary two-way "on-off" valve which will couple hydraulic fluid from the valve input to the valve output in the "on" position and then move to the "off" position where it will maintain the pressure on the down stream side while enabling the pressure on the upstream side to be removed.

Abstract: A variable effort power steering system for an automobile includes a rotary valve power steering gear, a detent type variable effort detent system whereby a fluid detent pressure proportional to vehicle speed operates on a detent between an input member of the steering gear and an output member of the steering gear to prevent relative angular displacement therebetween until steering handwheel effort exceeds a threshold magnitude increasing with increasing detent pressure, and a shunt system between the two working chambers of the steering assist fluid motor. The shunt system includes a shunt valve in a shunt passage between the working chambers which is closed at zero or low vehicle speed and is progressively opened by detent pressure as vehicle speed increases whereby progressively more fluid is shunted from the active working chamber to the reservoir at higher vehicle speeds.

Abstract: A hydraulic motor has its lube drain connected to the motor return line. A motor seal protector valve has a pilot which responds to pressure in the motor return line. Normally, the valve connects system pressure to the motor inlet. High pressure in the return line causes the pilot to move the valve to block the motor feed line and then to connect the motor feed line to sump. In a preferred embodiment, system pressure is connected to the plot to "lock up" the valve in response to return line overpressurization.

Abstract: A solenoid-operated fluid control valve having manual override and fluid latching for establishing a fluid path between a supply port and a delivery port when a brake-release solenoid pilot valve coil is momentarily energized to cause a pilot piston to close an exhaust valve and to open a supply valve for causing feedback pressure to be fed from a delivery chamber to a pilot chamber for fluid latching the pilot piston in a brake-release position until a brake-application solenoid pilot valve coil is momentarily energized which causes the pilot chamber to exhaust to atmosphere so that the pilot piston returns and opens the exhaust valve and allows the closure of the supply valve.

Abstract: The fluid distributing device, more especially for remote control, comprises a body (2) having bores (3) with parallel axes in which are slidably mounted slide valves (4) associated in pairs and controlled by push-rods (5) actuated by an oscillating cam (6). Each slide valve bore (3) has a groove (8) connected to the pressurized fluid intake, each slide valve being combined with a chamber (9) limited by at least one transverse annular surface (b) of the slide valve and connected to the reservoir by a constriction.

Abstract: A pilot valve having a universally tiltable joy stick further includes a cam attached to said joy stick and movable therewith. A plunger is selectively movable into engagement with the cam for latching the joy stick in a selected one position. Fluid is supplied to the plunger for developing a force acting thereon to move the plunger into engagement with the cam. The fluid force is eliminated and the plunger disengaged from the cam to delatch the joy stick.

Abstract: A tractor hydraulic control system of the kind comprising a power lift with a hydraulic actuator (12) and a main control valve (17) controlling the supply of fluid from a pump (19) to the actuator, the system including selector valve means (50) interconnected with the main control valve (17) and movable between a first position in which flow to and from the actuator (12) occurs via the selector valve means under the control of the main control valve and the associated system control mechanism (28) and a second position in which the actuator is hydraulically locked in a given position and an external services outlet (51) is placed in communication with the pump. Linkage means (60,61,62) operatively connects the selector valve means (50) and the system control mechanism (28) to condition the main control valve (17) to cause the pump (19) to supply fluid to the external service outlet (51) via the selector valve means on movement of the selector valve means to the second position.

Abstract: A control valve and a multiple control system therefor for controlling a plurality of remotely positioned hydraulically actuated underwater devices. The control valve includes first and second equal size pilot pistons acted upon by first and second pilot ports, respectively, for moving the valve to either an open or closed position, and third and fourth unequal size pilot pistons acted upon by third and fourth pilot ports for moving the valve to either an open or closed position. The control valve may be operated in an electro-hydraulic control mode by the use of electrically actuated valves controlling the supply of fluid to the first and second ports. In addition, the control valve can be operated in a hydraulic mode by hydraulically controlling the supply of fluid to the third and fourth pilot ports.

Abstract: A manually-operable hydraulic control device of the hydraulic pressure liquid directional control type, with hydraulic position-retention, particularly for regulating the flow of pressurized fluid supplied to the power jack of a component or implement of an earth moving machine, comprises a pair of valves and a control lever having a central neutral position and two respective extreme operative positions for controlling the said valves. The device is provided with hydraulic means for retaining the control lever in at least one of the said extreme operative positions.

Abstract: In an agricultural vehicle in which a power takeoff modulating valve is shifted in response to a control lever so as to pass pressurized hydraulic fluid through a groove in the outer surface thereof between recesses in an adjacent bore wall for application to a power takeoff clutch to cause engagement of the clutch, application of the hydraulic fluid pressure to the clutch is modulated by an arrangement which selectively diverts the pressurized hydraulic fluid away from the clutch and to a sump in accordance with the rate of pressure increase of the hydraulic fluid to prevent excessively rapid engagement of the clutch. The hydraulic fluid is sumped by a trimmer valve having a first end which immediately responds to high fluid pressures by sliding into a position which sumps the conduit supplying hydraulic fluid to the clutch by an amount directly related to the pressure.

Abstract: A hydraulic system includes a selective control valve and a cam member movable to selected positions for controlling a hydraulic cylinder powered by a pump. A follower is urged to a locking relationship with the cam by a hydromechanical mechanism to releasably hold the control valve in the selected positions. The hydromechanical mechanism includes a bore exposed to sump pressure and to pressure upstream and downstream from a metering valve in a passage interconnecting the pump and the control valve. A hollow apertured sleeve is movably mounted in the bore. An apertured piston is slidably received by the sleeve. A rod, engageable with the follower, extends through the piston and sleeve apertures. A first spring interconnects the rod and the piston and a second spring interconnects the piston and the sleeve. The sleeve moves to a preload position in response to a no-flow differential pressure between the sump and the passage to urge the follower via the rod towards its locking position.

Abstract: A shut-off valve arrangement for a gas turbine engine fuel supply system includes a shut-off valve in a fuel supply line to the engine, and a drain valve communicating with said supply line downstream of the shut-off valve. Said shut-off valve and drain valve are responsive to a servo pressure signal which is applied through flow restrictors such that the drain valve shuts before the shut-off valve, but opens after the shut-off valve.

Abstract: A spool valve for use with pressurized fluid to control components of a control system. The spool valve has two stable positions in one of which the spool is firmly held by pressurized fluid.

Abstract: A pressure biased control valve holding the valve in the actuated position against the force of a return spring operating in connection with a linkage having a separate return spring and a loss motion connection to allow the valve and linkage to operate independently to the return position and assure the pressurized fluid in the valve maintains the valve in the actuating position regardless of pressure changes in the hydraulic system.

Abstract: A delaying device for a fluid system for operating a hydraulic motor (10) wherein electrically operated pilot valves (39,40) are actuated by limit switches (13,13') in the motor to control flow through pilot lines (37,38) into a control block (20) and then to and from the motor, said delaying device comprising a dashpot cylinder (46) connected to said pilot lines for momentarily continuing to supply fluid to said control block (20) after pilot valve (39 or 40) is shut off.

Abstract: The disclosure is directed to a closed center, pressure compensated hydraulic system which uses a multiple section hydraulic control valve in conjunction with a variable output hydraulic pump. The hydraulic control valve has a plurality of independently operable power spools each of which is used to control the flow of hydraulic fluid to a separate hydraulic actuator and load. Each valve section includes an automatic spool positioner which enables the operator to move the valve handle to a preselected position, the power spool thereafter being retained in such position until the actuator completes its stroke. After completion of the stroke, the automatic spool positioner causes the power spool to return to the neutral position. The multiple section hydraulic control valve also includes means for selecting the highest demand or work port pressure, and for controlling the variable output pump as a function of this selected pressure.

Abstract: A source of fluid, regulated as to pressure intensity before entry into a control valve assembly, drives a fluid biased piston motor. A mechanically actuated and fluid held valve in the control valve assembly controls pressurization of a pressure chamber in the piston motor displacing the motor piston through its return stroke. Pressure differential on opposite sides of a fluid operated valve actuator insures rapid opening of the valve and holding thereof in its open position during the motor piston return stroke. At the end of the return stroke, the pressure differential is eliminated to allow spring-biased closing of the valve and venting of the pressure chamber.

Abstract: A four-way spool valve controls a double acting fluid motor for locking or unlocking a part such as a tailgate. The valve is spring-urged to a locking position and hand-operable to its unlocking position. A position at the end of the valve is pressurized when in the unlocking position to counteract the spring. This piston monitors supply pressure so that the valve will be automatically shifted to its locking position when pressure drops. This will insure a locked position of the part when pressure is reapplied.