Abstract: A pilot valve configured to provide a control pressure within a dynamic fluid system, the pilot valve comprising: (a) a valve body having a supply port, a return port, and a control pressure port, the pressure control port in fluid communication with a subsequent valving component; (b) an axial bore formed in the valve body and in fluid communication with each of the supply, return, and control pressure ports; (c) a valve spool slidably supported within the axial bore of the valve body, the valve spool configured to control fluid flow through the supply, return, and control pressure ports, and to vary the rate of change of area of at least one of the supply and return pressure ports upon being displaced, thereby providing a variable resistance to fluid flowing therethrough and reducing the quiescent power of the pilot valve; and (d) means for displacing, in a selective manner, the valve spool within the axial bore about the supply, return, and control pressure ports to apportion fluid therethrough to provide

Abstract: The present disclosure relates to isolation and reconfiguration schemes, architectures and methods for use in aircraft hydraulic systems. The main hydraulic system of each hydraulic section of the aircraft hydraulic system can be isolated from one or more consumers in the event of a leak without the use pressure from the backup system. Further, in some embodiments, the main hydraulic system of each hydraulic section of the aircraft hydraulic system can be isolated from one or more consumers in the event of a leak without the use pressure from the backup system and the main system.

Abstract: A hydraulic valve device has a fluid port arrangement (10) with various ports extending at least partially in the valve housing (14), and has a movable control device (18) for at least partially activating the ports. The control device (18) can be acted on at two opposite control sides with a control pressure (XA, XB) of an activation unit (46). A valve device of narrow construction and functionally reliable is created by a media-conducting duct (66) with a guide path extending at least partially as an open duct channel that can be closed off by a cover part or by other housing parts of the multi-part valve housing (14), to conduct the control pressure (XB) from the activation unit (46) to the assignable control side of the control device (18).

Abstract: A heat exchanger structure including multiple fluid circuits, through which respective streams of a first fluid pass from a stream inlet to a stream outlet to transfer heat to or from a second medium. The fluid circuits are arranged into at least a first group and a second group, at least the first group consisting essentially of only fluid circuits that perform substantially similarly according to at least one selected performance criterion. A control sensor for at least the first group generates a signal representative of a parameter of the first fluid in the associated group. A valve for at least the first group is in fluid communication with of all the streams of the associated group so as to be able to control the flow of fluid through the streams of the associated group in parallel.

Abstract: A hydraulic valve device, especially an LS current regulating valve, includes a fluid connection arrangement (10). As the respective control device (14) associated with a useful connection (A) comprises a control slide (16) upstream of which a pressure balance (18) is mounted in the fluid direction towards each useful connection (A, B), any system vibrations occurring in the load sensing regulating circuit can be better controlled and the respectively connected hydraulic consumer can be subjected to a constant current regulation.

Abstract: A valve system for activating a piston of a piston-cylinder arrangement for a hydraulic or fluid device includes a pilot control valve including 3/2-way valve and a main valve arrangement having a first and a second main valve. The first and second main valves include 2/2-way valves, wherein in a first position the pilot-control valve is configured to move the first main valve into an open position so as to direct a path for a high pressure fluid to a space above the piston, and wherein in a second position the pilot-control valve is configured to connect the space to a low-pressure tank so as to relieve a pressure in the space above the piston via the second main valve, and wherein the pilot-control valve is configured to open the second main valve and configured to close the first main valve.

Abstract: A solenoid operated valve and method of assembly characterized by a threaded connection between the pole piece (69) and the cage (11), the threaded connection (75) including a first threaded connecting portion fixed in relation to the pole piece and a second threaded connecting portion fixed in relation to the cage and in threaded engagement with the first threaded portion such that relative rotation of the first and second threaded portions would vary the axial spacing between the proximal end of the pole piece and the valve seat (38) over a range of adjustment; and an anti-rotation device interposed between the first and second threaded connecting portions for locking the first and second threaded connecting portions against relative rotation to fix the axial spacing between the proximal end of the pole piece and the valve seat within such range of adjustment, which axial spacing regulates the maximum pressure that can be supplied to the control port (25).

Abstract: A solenoid valve apparatus includes a solenoid valve and a switching device that switches between a first state in which the working fluid in the pump chamber is discharged when the solenoid valve functions as a regulator valve and a second state in which discharge of the working fluid from the pump chamber is prohibited when the solenoid valve functions as the electromagnetic pump.

Abstract: A proportional pressure controller includes a body having inlet, outlet, and exhaust ports. A fill valve communicates with pressurized fluid in the inlet port. A dump valve communicates with pressurized fluid from the fill valve. An inlet poppet valve opens by pressurized fluid through the fill valve. An exhaust poppet valve when closed isolates pressurized fluid from the exhaust port. An outlet flow passage communicates with pressurized fluid when the inlet poppet valve is open, and communicates with the outlet port and an exhaust/outlet common passage. A fill inlet communicates between the inlet passage and fill valve, and is isolated from the outlet flow passage, exhaust/outlet common passage, and outlet and exhaust ports in all operating conditions of the controller.

Abstract: A flow controller includes a flow detection unit that includes a detection unit for detecting the flow rate of a fluid; and a flow control unit that is coupled to the flow detection unit and that is capable of adjusting the flow rate of the fluid. The detection sensor constituting the detection unit includes a thermal flow sensor using MEMS technology, and the flow rate of the fluid that has been detected by the detection sensor is output to a control unit. In addition, in the flow control unit, the supply state of air to a supply room is switched by each of a supply-use solenoid valve and an exhaust-use solenoid valve, and on the basis of the supply state of the air, a control valve opens and closes.

Abstract: A pressure control system remotely controls pressure within one or more remote zones, each respectively connected to an enclosure through a conduit, by controlling flow of a fluid into and out of each enclosure. The pressure of the fluid is measured within each enclosure. An estimated pressure within each zone is computed, as a function of the measured pressure in the enclosure and known characteristics of the conduit and the zone. For each zone, an inlet proportional valve and an outlet proportional valve of each enclosure is operated so as to control the input flow rate of the fluid into the respective enclosure and the output flow rate of the fluid out of the enclosure as a function of a pressure set point and the estimated pressure, thereby regulating pressure within the zone in accordance with the pressure set point.

Abstract: A double valve having inlet, outlet, and exhaust ports maintains an outlet pressure below one percent of inlet pressure during a faulted state while maintaining a relatively small exhaust for reduced overall valve size. Crossover passages receive inlet pressure through main crossover poppets when the respective valve units are not in a deactuated position. When the valve units are in a deactuated position, then the crossover passages receive inlet pressure through respective bypass passages whose flow rate can be controlled independently from the size of the crossover poppets. The use of bypass passages provides particular benefits for double valves for non-press applications which have a ratio of exhaust flow coefficient to inlet flow coefficient that is less than about 2.5.

Abstract: A proportional pressure controller includes a body having inlet, outlet, and exhaust ports. A fill valve communicates with pressurized fluid in the inlet port. A dump valve communicates with pressurized fluid from the fill valve. An inlet poppet valve opens by pressurized fluid through the fill valve. An exhaust poppet valve when closed isolates pressurized fluid from the exhaust port. An outlet flow passage communicates with pressurized fluid when the inlet poppet valve is open, and communicates with the outlet port and an exhaust/outlet common passage. A fill inlet communicates between the inlet passage and fill valve, and is isolated from the outlet flow passage, exhaust/outlet common passage, and outlet and exhaust ports in all operating conditions of the controller.

Abstract: A fluid pressure circuit that can, in either case where a first actuator that is fed from a first pump or a second actuator that is fed from a second pump is operated, by allowing feeding of the hydraulic fluid to a specific actuator from either the first or second pump, improve interlockability with the specific actuator. A control valve is incorporated with a plurality of first-group spools fed from a drive pump and a plurality of second-group spools fed from an idle pump. A solenoid selector valve unit switches a pilot line of a second-group tool controlling spool to a communicating state at the time of detection of a spool operation by a first pressure switch and switches a pilot line of a first-group tool controlling spool to a communicating state at the time of detection of a spool operation by a second pressure switch.

Abstract: A valve control unit that prevents a decline in interlocking operation performance when pilot pressure control of a plurality of pilot-operated control valves is carried out by proportional solenoid valves. First and second proportional solenoid valves include a Common Operation Table of lever operation amount/boom-up pilot pressure characteristics and are inputted with a common boom-up lever operation amount. A third proportional solenoid valve also includes the Operation Table and is inputted with a stick-in lever operation amount common to the fourth proportional solenoid valve. The fourth proportional solenoid valve includes an Operation Table of lever operation amount/stick-in pilot pressure characteristics different from that of the first, second, and third proportional solenoid valves and is inputted with the stick-in lever operation amount common to the third proportional solenoid valve.

Abstract: A pressure control valve is provided, which can variably control the set pressure of the pressure control valve through manipulation of a signal pressure generation device in an operator's seat or the like.

Abstract: A softstart valve means comprises a main valve member which is only switched over after a certain time from a closed position into an open position. The opening force required for switch over of the main valve member can be produced selectively in a manner dependent from pressure obtaining in a secondary duct or in a time dependent fashion. The respective operational mode can be selected by actuation of switch over means.

Abstract: The invention relates to a piloted valve, particularly a piloted proportional throttle valve, having a valve piston (29) displaceably guided in the longitudinal direction in a valve housing (13) having a fluid inlet (2) and outlet (1), the front side (27) whereof can be pressurized against a main valve seat (25) by fluid pressure acting on the back side thereof, having a pilot valve device comprising an actuating member (7) displaceable in the longitudinal direction by means of an electrically actuatable magnet system (4), working together with a pilot valve seat (37) in a bore (17) of the valve piston (29) connecting the back side thereof to the fluid outlet (1) on the front side of the piston, in order to reduce the fluid pressure on the back side of the piston (29) for an opening motion when the pilot valve seat (33) is released, a flow baffle device (39) being disposed between the back side of the piston and the fluid inlet (2) of the housing (13) for building up the fluid pressure pressurizing the piston

Abstract: A system and a method for partial stroke testing of a critical valve using a bypass valve includes flowing two streams of gas simultaneously through a bypass valve, opening the critical valve with the gas from the bypass valve, and determining a calibration time interval for closing the opened critical valve to a preset partial stroke testing position. The method includes determining a measured time interval for closing the opened critical valve, creating a tolerance band, and comparing the measured time interval to determine if the critical valve passes the partial stroke testing. The system includes a two stage bypass valve, having four solenoid valves. The system includes a processor with a memory having partial stroke testing logic. Each solenoid valve and the bypass valve include a pressure sensor.

Abstract: A pressure control system is disclosed. The control system in one embodiment includes a main body comprising a pilot chamber wherein an intake port and a discharge port are formed, and a spool comprising an upper slide and a lower slide. The spool in this embodiment is attached by a spring to the upper part of the main body. The exhaust apparatus pressure control system includes an absolute pressure sensor for detecting the pressure in the intake port and a differential pressure sensor for detecting the difference between the pressure in the intake port and atmospheric pressure; a control valve for supplying a pressure regulating gas to the pilot chamber; and a control circuit for sending switching signals to the absolute pressure sensor and the differential pressure sensor, and driving the control valve based on the output from the absolute pressure sensor or differential pressure sensor.

Abstract: A hydraulic system having at least one hydraulic valve for actuating a component, wherein a control pressure acting on the hydraulic valve can be activated through a supply pressure of a pilot circuit having at least one actuator. At least one pressure reduction apparatus is connected in series with the actuator.

Abstract: Apparatus and method for fail-safe high-speed-pneumatic valve is disclosed. Fail-safe dependability is provided by a spring-loaded normally-closed pneumatic actuator. When the spring-loaded actuator is pressurized, the normally closed mechanism is actuated to the valve active position. Concurrently, the pressure is directly applied to deflect a diaphragm or a bellow-assembly back to sealing position. Ultra high purity embodiments with standard dome shaped diaphragms are disclosed. Additional high conductance diaphragms and bellows embodiments are employed for higher conductance valves. Novel flow path layouts are disclosed. The valves are applicable for fast gas and fluid switching and are particularly suitable for high productivity Atomic Layer Deposition (ALD) applications. Additional embodiments cover improved diaphragm and seal reliability, externally adjustable valve conductance, improved valve safety and high temperature valve seals.

Abstract: A method and a valve arrangement are provided for electronic wear state determination of the valve arrangement for controlling a process medium flow. A valve element, which is arranged so as to move axially within a valve housing, is moved via electrically drivable linear drive means on the basis of positioning regulation. The valve element has an essentially constant drive force applied to it, and a position speed profile over the switching travel of the valve element is determined by detecting the speed as a function of the current position of the valve element. A change profile is created by comparing the determined speed profile with previous position speed profiles, as a measure of the position-dependent wear state of the valve mechanism.

Abstract: The invention relates to a device for controlling the opening and closing of a compressed gas consuming circuit (U), the device comprising a normally-closed two-position cutoff valve (2), said cutoff valve (2) having a pilot chamber (2a) and a counter-pilot chamber (2b) permanently in communication with a source (P) of compressed gas, directly for the pilot chamber (2a) and via a constriction (6) for the counter-pilot chamber (2b), the counter-pilot chamber including a purge branch connection (8) that is opened or closed by a two-position, two-port valve (9).

Abstract: A hydraulic trip unit for a valve unit in a prime mover plant is described, with monitoring passages which are grouped together in a hydraulic block and interconnected forming a 2 out of 3 circuit, of which each monitoring passage is provided with a solenoid valve unit, with a power oil line connection which is provided on the hydraulic block and from which an emergency oil passage and an auxiliary emergency oil passage extend inside the hydraulic block, of which the emergency oil passage can be connected to the valve unit and the auxiliary emergency oil passage is connected via connecting lines to a solenoid valve unit in each case, wherein a first connecting line feeds a first and third solenoid valve unit, a second connecting line feeds the second and a first solenoid valve unit, and a third connecting line feeds the third and second solenoid valve unit.

Abstract: A manifold-type solenoid valve comprises a main valve section and a solenoid operating section. The main valve section has a spool in a valve hole to which respective switching flow paths for supply, output, and discharge are opened. The main valve section comprises connecting flow paths for collective supply and/or collective discharge having connecting ports, output ports, and an external port for connecting an external piping for independent supply or independent discharge. The output ports are in communication with the switching flow path for output. The connecting flow paths for collective supply and/or collective discharge are in communication with the switching flow path for supply and the switching flow path for discharge. Additionally, the external port is in communication with the switching flow path for supply or the switching flow path for discharge.

Abstract: There is provided a circuit configuration which does not require an additional fail-safe mechanism caused by the addition of a changeover valve in a hydraulic pressure control device for an automatic transmission having a function to directly supply a line pressure and hold (lock) an engaging pressure by combinations of electromagnetic valves and changeover valves. A changeover valve 20 is disposed between an output port 12 and a feedback port 13 of a linear solenoid valve 10 of the hydraulic pressure control device for an automatic transmission.

Abstract: A composite valve includes a main valve unit that individually opens and closes a vacuum channel for applying vacuum pressure to a load and a pressure channel for supplying vacuum-breaking pressure fluid with two valves for vacuuming and pressurizing; a channel combining section that connects the vacuum channel and the pressure channel to the load via a combining port; and a pilot valve unit that opens and closes the valve members individually with two pilot valves. The main valve unit, the channel combining section, and the pilot valve unit have the same width, and connect to one another in line along the axis of the valve.

Abstract: The present invention includes fluid control systems employing compliant electroactive materials.

Abstract: A system for on-line testing of an emergency shut-off valve includes a first emergency shut-off valve and a control for initiating a test on the first emergency shut-off valve. The system also includes a fluid actuator for opening and closing the first emergency shut-off valve. A subsystem is also provided for testing the first emergency shut-off valve without fully closing the shut-off valve in response to a signal from the control. In this system, a second solenoid valve bleeds off pressurized fluid to move the emergency shut-off valve from a fully opened to a partially closed position functions as a second emergency shut-off valve. A second emergency shut-off valve is also provided in series with the first emergency shut-off valve and a bypass around the second emergency shut-off valve allows the second emergency shut-off valve to be tested by being fully closed without shutting down the process.

Abstract: A tube defines a cavity. Normally-open fitting (2) and normally-closed fitting (3) are respectively fitted into the tube to form ports (34),(35) having seats (40),(13). A body secured to fitting (3) defines a chamber (26) to which port (35) leads. Body (4) defines holes (27),(30) leading into chamber (26). A solenoid assembly (6) is slidable within chamber (26), includes a coil, segregates chamber (26) to chambers (7),(29) which communicate respectively with holes (27),(30) and defines a chamber (16), a seat (18), a seal (14) and an orifice (33) leading between seat (18) and seat (13). A rod-piston assembly includes a rod (37) attached to: assembly (6), sealably passing through body (4) into cavity and preventing gas communication between cavity and chamber (7); and a piston with a seal (39). A magnetic rod (15) slides within chamber (16). Spring (17) urges rod (15) towards seat (18) to seal orifice (33). Spring (12) urges assembly (6) towards seat (13) to seal port (35).

Abstract: Attaching/detaching workability of a fitting block to/from an solenoid valve assembly is improved, and a fixing strength of the fitting block to the solenoid valve assembly is enhanced. The fitting block 41 is intended to be detachably mounted to the solenoid valve assembly 12, and the fitting block 41 is provided with port connecting tubes 42 and 43 detachably fitted in output ports A and B, and tube fittings 44 and 45 to which tubes 46 are connected. The fitting block 41 is further provided with an engagement projection 52 which is engaged with a concave portion formed in the solenoid valve assembly 12, and the fitting block is fixed to the solenoid valve assembly 12 via a portion of the engagement projection 52 by a clip 53 engaged with an engagement groove 57 formed in the engagement projection 52.

Abstract: A valve manifold includes a valve body carrying pairs of laterally spaced piston actuated valves controlled by control modules operative to selective pressurize and exhaust an outlet port connected to a fluidic device and configured in grouping permitting varying valve functionalities.

Abstract: The invention relates to an electrohydraulic valve system comprising a feeding duct (P), a working duct (A), and a discharge duct (T), a first and a second valve mechanism (20, 30), each of which is provided with a valve piston (3.1), a control device, and a magnetic regulating device for impinging the valve piston (3.1, 3.2) with a controlled actuating force. The first and the second valve mechanism (20, 30) are placed parallel to each other. The first valve mechanism or the second valve mechanism is active and performs the function of the electrohydraulic valve system while the other valve mechanism is passive during operation. The control device of the active valve mechanism activates the passive valve mechanism and deactivates itself when said control device recognizes a fault while the control device of the passive valve mechanism activates itself and deactivates the active valve mechanism when the control device of the passive valve mechanism recognizes a fault.

Abstract: A pressure control system is disclosed. The control system in one embodiment includes a main body comprising a pilot chamber wherein an intake port and a discharge port are formed, and a spool comprising an upper slide and a lower slide. The spool in this embodiment is attached by a spring to the upper part of the main body. The exhaust apparatus pressure control system includes an absolute pressure sensor for detecting the pressure in the intake port and a differential pressure sensor for detecting the difference between the pressure in the intake port and atmospheric pressure; a control valve for supplying a pressure regulating gas to the pilot chamber; and a control circuit for sending switching signals to the absolute pressure sensor and the differential pressure sensor, and driving the control valve based on the output from the absolute pressure sensor or differential pressure sensor.

Abstract: A control valve apparatus couples pressurized fluid to first and second actuators using first and second double valves. The first double valve includes first and second crossover passages and first and second pilots. The second double valve includes third and fourth crossover passages and third and fourth pilots. A first interconnection couples the first crossover passage with the third pilot fluid inlet. A second interconnection couples the second crossover passage with the fourth pilot fluid inlet. A third interconnection couples the third crossover passage with the first pilot fluid inlet. A fourth interconnection couples the fourth crossover passage with the second pilot fluid inlet. Thus, operation of each pilot depends upon receiving pressurized fluid from the other double valve which is only present when the other double valve is not in a fault condition.

Abstract: A control valve structure for an oxygen machine uses a motor to link a disc to spin, which activates a pair of valve rods to open and close in sequence through rotation of the motor to control air flow.

Abstract: Disclosed is an infinitely variable directional valve comprising a seat slide on which a valve cone is formed which is prestressed counter to a valve seat in the initial position of the directional valve. The directional valve is configured with a pilot control device wherefore a pilot control valve seat which interacts with a pilot control valve cone is provided inside the closing cone.

Abstract: A hydraulic circuit of an option device for an excavator is disclosed, which can constantly supply hydraulic fluid to an option device, such as a breaker and so on, selectively mounted on the excavator, irrespective of the size of a load occurring when the option device operates, and control respective flow rates required for various kinds of option devices. The hydraulic circuit includes a variable hydraulic pump, an option device, a first spool shifted to control hydraulic fluid fed to the option device, a poppet and a piston, an option spool shifted to control hydraulic fluid fed to the option device via the first spool, a second spool shifted to control hydraulic fluid fed to a back pressure chamber of the poppet, and a control means installed in the poppet and controlling hydraulic fluid passing through an orifice of the poppet when the piston and the poppet are pressed by the hydraulic fluid fed from the hydraulic pump, through the shifting of the second spool.

Abstract: To construct solenoid valves used as a solenoid assembly by assembling the solenoid valves in a group so that both collective wiring and individual wiring can be performed and the solenoid valves can be simultaneously cut off from a collective wiring power supply and an individual wiring power supply. An individually receiving connector for connecting an individual feeding connector, a switching member being able to be freely shifted between a first operational position where the connection of the individual feeding connector to the individual receiving connector is prohibited and a second operational position where the connection is allowed, and a switch operating in response to operation of the switching member are provided in a solenoid valve connected to a power supply by collective wiring.

Abstract: The valve includes a body having five surfaces and a plurality of blind holes, grooves and channels interconnected with the blind holes to form communication net. Two rectangular diaphragms are embedded separately into the grooves so as to selectively open and close the blind holes. An internal sliding base with an external sliding base coupled to the external periphery thereof and comprises a sliding section and an internal press pillar disposed separately on two corresponding ends of the bottom of the sliding section. The two internal press pillars are capable of selectively opening and closing the two diaphragms. The external sliding base includes an external press pillar disposed separately on both corresponding ends of the concave groove. A casing for covering the external periphery of the external sliding base is secured with the body. At least one elastic member is installed between the top surface of the casing and the external sliding base.

Abstract: A distributed hydraulic system locates a control assembly, that has electrohydraulic valves and a electronic controller, adjacent the respective hydraulically powered actuator controlled by that assembly. The control assembly includes a manifold block with ports to that the pump, tank return and actuator fluid conduits connect. One or more pressure ports are provided on the manifold block at which to sense pressure at different locations therein. A controller housing, in addition to containing an electronic function controller, also contains a separate pressure sensor for each pressure port, and is mounted against the manifold block so that each pressure sensor connects to a pressure port. The manifold block also has a pair of exterior walls that extend on opposites sides of the controller housing to protect the electronic controller. Other features that facilitate distributing the hydraulic control adjacent the actuators are provided.

Abstract: A control valve for operating a fluid-actuated device includes a fluid inlet, a fluid outlet and a passage in fluid communication between the fluid inlet and the fluid outlet, the passage defining a longitudinal axis. A valve seat is disposed in the passage and includes an upstream diameter and a downstream diameter, the downstream diameter smaller than the upstream diameter. A ball poppet is positionable in a seated line contact position with the valve seat. The valve seat has a valve seat angle relative to a centerline of the longitudinal axis that is greater than an angle formed by the centerline and a line tangent to the ball poppet at the seated line contact position.

Abstract: A device is disclosed for controlling a variable displacement compressor. The device comprises a microvalve operated control valve. A microvalve device for controlling fluid flow and a micro spool valve for use as a microvalve are also disclosed.

Abstract: The supply of operating air or oil to a press, shears or like machine is controlled by a pair of spool valves connected in series and each operates a pair of switches. The switches connect DC current to the solenoids via external relays which open and close the valves. The external relays are standard components on the switchboard of the machine subject to control. Sharing the control between two valves allows malfunction in either valve to indicate the system needs correction while at the same time preventing supply to the machine. The switches are coupled to the DC switchboard of the machine by cables and thus can be retrofitted.

Abstract: Electropneumatic double regulating valve for an air-operated vehicle brake system, which is disposed centrally on a wheel axle, equipped with two brakes, with a common relay valve housing (1), in which is integrated for each brake an assigned regulating valve unit, which comprises for valve actuation a control piston, which can be axially adjusted and is disposed inside an assigned control chamber (3a, 3b) and which is driven with a control pressure by way of an electromagnetic pilot valve assembly, housed in an adjacent pilot valve housing, for independent axial adjustment, whereby the pilot valve housing is connected detachably to the relay valve housing (1) by way of a sealing arrangement that lies in-between, whereby the sealing arrangement is designed as one-piece and comprises two sealing ring segments (5a, 5b), which are in essence ring-shaped and are assigned to one control chamber (3a, 3b) each and which are connected together by means of several footbridges (6a to 6c), which are molded on in-between

Abstract: A valve assembly having a fluid switch and a main valve for controlling fluid pressure in a working volume in three control states wherein the main valve has three ports for fluid, flow of fluid through a first port and a second port being controlled by the fluid switch being provided with an electrical signal in a first state or a second state respectively, and flow of fluid through the third port being controlled by alternating the signal, preferably rapidly, between the first and second states.

Abstract: A double valve is constructed from first and second unitary valve assemblies each having a respective inlet port, a respective outlet port, a respective exhaust port, a respective first cross-mirror port, and a respective second cross-mirror port. A first plate is coupled to the first and second unitary valve assemblies and includes respective passages to provide a common inlet port coupled to the respective inlet ports of the first and second unitary valve assemblies and a common outlet port coupled to the respective outlet ports of the first and second unitary valve assemblies.

Abstract: The invention relates to a control valve (10) for controlling the pressure and flow of hydraulic oil from or to the working connections (A, B) of a consumer. The pressure and the pressure flow are controlled by means of at least one sliding piston which can be actuated by at least one drive mechanism and which can be displaced in a slider hole and in co-operating annular channels. The invention is characterized in that the annular channels are symmetrically arranged, whereby a tank connection annular channel is arranged in the symmetrical centre point on a symmetrical axis. Annular channels associated with the working connections (A, B), pump-pressure annular channels, load-sensing annular channels and end-chamber annular channels are arranged behind each other on both sides. According to the invention, the latter can be connected to other channels.

Abstract: The invention relates to a valve system comprising a housing, an actuator, a main valve disposed between an inlet chamber and an outlet chamber, and a pilot chamber. Said pilot chamber is linked with the outlet chamber via a main valve, comprising at least one pilot valve member and one valve body linked with the electromagnetic actuator, and with the inlet chamber via at least one connecting channel. The invention is characterized in that the stationary seat of the main valve is formed by an insert that is mounted in the; housing of the valve system. The main valve member is impinged upon on its diametrically opposed surfaces by the pressure present in the inlet chamber and the pressure present in the pilot chamber. The pilot chamber is linked with the inlet chamber via a connecting channel that extends through the main valve member. The pilot valve member is formed by the insert mounted in the housing of the valve system or by the housing.