Abstract: A low-flow diaphragm valve has a flexible diaphragm that cooperates with a portion of a valve body to open and close the valve. The diaphragm may have a dome for seating in a passage between the inlet and outlet of the valve. The diaphragm may have one or more ribs for seating against other portions of the body located around the passage. The valve body may include openings or interruptions to permit fluid to flow through the valve, as well as to permit relatively small particulate matter to flow through even though the ribs contact the body such that the ribs and openings affect flow and may perform screening functions to block or restrict particulate matter of relatively large size from flowing to the passage between the dome and the valve body.

Abstract: A linear solenoid valve includes a solenoid having a coil wound around a coil bobbin, a fixed core, and a movable core for being attracted to the fixed core when the coil is energized, and a valve mechanism having a valve element for selectively bringing an inlet port and an outlet port into and out of fluid communication with each other responsive to a displacement of the movable core. The movable core has a nonmagnetic layer formed on an outer surface thereof and having a predetermined thickness.

Abstract: A spool type control valve is operated by an electrically driven pilot valve. A pilot piston is attached to the control spool. As an electrical actuator moves the pilot spool, a greater pressure is applied to one side of the pilot piston than the other side, which causes movement of the control spool. When the control spool reaches the desired position, its positional relationship to the pilot valve defines a pressure differential across the pilot piston which exerts a net force on the control spool that counterbalances a spring force acting on the control spool. This defines an equilibrium position at which the control spool remains until subsequent motion of the pilot spool occurs which alters the pressure differential across the pilot piston.

Abstract: A valve assembly comprising a valve body, a first movable pressure responsive element, and a second pressure responsive movable element, wherein the valve assembly further comprises a resilient biasing element and a movable third pressure responsive element, the resilient biasing element extending between the third pressure responsive element and the valve body and the third pressure responsive element being adapted to act on both the first and second pressure responsive elements to transmit the biasing force of the resilient biasing element to both the first and second pressure responsive elements.

Abstract: A novel three-way valve comprising a valve body, a valve sleeve for adjustable position mounting within the body, and a valve stem movable so as to selectively form a pathway between line recesses in the valve sleeve. Three line recesses are used to form a three way valve and the front and rear line recesses are provided around the diameter such that an increased number of apertures may be provided while reducing the diameter of the apertures themselves to provided the necessary fluid flow with a reduced throw requirement for the valve stem. Exhaust valves are provided to relieve pressure on the unused fluid path. Preferably, the apertures are equi-spaced around the recesses diameter to create a more efficient fluid flow. The valve has a knob and/or a hex key for making fine adjustments to the position of the valve sleeve for optimal efficiency.

Abstract: When the pressure in a main fluid supply channel is lower than a no-load operation start pressure, and auxiliary fluid supply channel is communicated with the main fluid supply channel through the internal flow channel of a spool, and as the pressure rises within the main fluid supply channel, the spool moves against the biasing force of a biasing member, and the area of opening of the auxiliary fluid supply channel is reduced with regards to opening of the internal flow channel. When the pressure in the main fluid supply channel rises and reaches a no-load operation start pressure, the area of opening in the auxiliary fluid supply channel with regards to opening of the internal flow channel becomes smaller and while connected to the main fluid supply channel, the auxiliary fluid supply channel is connected to the return flow channel.

Abstract: An apparatus and a method for fluid distribution and control. A valve body defines at least two pairs of chambers which are each connectable to an external fluid circuit. A mobile structure, which moves according to a controlling unit, forms an internal penetrating passage. An internal bearing surface, which is located at the first end of the internal passage, is capable of cooperating in a sliding manner with a stationary piston head. The internal bearing surface may move beyond either side of the piston head. When the mobile structure is in an extreme position, an end chamber of the valve body is in fluid communication with the internal passage. When coupled with a PSA adsorber system, the system is capable of supplying oxygen enriched air to an occupant of an aircraft.

Abstract: The present invention relates to a control valve for controlling flow of hydraulic fluid. The control valve comprises: a valve housing (10); a sleeve (11) slidable in a valve chamber in the valve housing (10); a first fluid conduit (12) for connecting the valve chamber to a source of pressurised hydraulic fluid; a second fluid conduit (14) for connecting the valve chamber to a fluid return for returning hydraulic fluid to a reservoir; and a third fluid conduit (16) for connecting the valve chamber to deliver hydraulic fluid to and receive hydraulic fluid from apparatus which uses the hydraulic fluid flow controlled by the control valve. The sleeve (11) is a tubular sleeve having, a tubular passage therethrough. The valve housing has a pair of spaced apart valve seat surfaces (22, 23), a first valve seat surface (22) which is engageable by a first end of the tubular sleeve (11) and a second valve seat surface (23) which is engageable by a second end of the tubular sleeve (11).

Abstract: A flow rate control valve comprising a valve body having an input port, an output port and an exhaust port, a valve means that is arranged in the valve body and controls the communication of the ports, and an electromagnetic operation means for driving the valve means. The valve means has a first valve body having a first valve portion that is seated on a partitioning plate disposed in a communication chamber formed between the input port and the output port and a first valve portion provided at one end portion, and a second valve body having a valve portion that comes in contact with the second valve portion.

Abstract: A pressure regulating valve, in particular a proportional pressure regulating valve, includes a valve body (1) with at least a pump connection (P), a use connection (A) and a tank connection (T). A piston (19), capable of being displaced by a controllable actuating device (29), is guided in the valve body (1). At the periphery of the piston, a recess (45) is formed and defines a peripheral annular gap (47) delimited by the control edges (49, 51) of the piston (19). In the piston (19), a passage (55) provides fluid communication between the front surface of the piston (19), subjected to the use connection (A) pressure, and the rear surface (35) of the piston (19), adjacent to a pressure chamber (37) located behind. The passage (55) of the piston (19) has, in the region proximate to the piston front surface, a restriction zone (57).

Abstract: A proportional solenoid valve or a camshaft adjusting device of motor vehicles has a valve housing and a piston movably arranged in the valve housing and provided with at least one pressure medium passage. A solenoid part is connected to the valve housing and acts on the piston. The valve housing has at least one working connector, a tank connector, and a pressure connector configured to supply a pressure medium into the piston. A leakage passage is provided that connects the pressure connector at all times to the at least one working connector.

Abstract: The invention relates to a valve system (1) with at least one valve body (2) and a longitudinal slide (3) slidably dispsoed therein which establishes or disrupts a connection between a feed line (4) and at least one inlet (5, 6) or outlet (7, 8) in the valve body 92). The valve system further comprises an electrochemically driven actuator (9) that displaces the longitudinal slide. The aim of the invention is to improve the valve system by simplifying the design of the valve body and the longitudinal slide and to provide a secure and reproducible connection between the inlet/outlet and the feed line in order to feed a corresponding actuating device with a hydraulic fluid. To this end, the longitudinal slide (30 has a longitudinal bore (10) connected to the feed line (4), which can be linked with the inlet (5, 6) or outlet (7, 8) via at least one connecting line (11, 12) that substantially extends radially outward from the longitudinal bore by displacing the longitudinal slide (3) by means of the actuator (9).

Abstract: A fluid control valve includes an adjustable soft start capability and pressure indicator device. The fluid control valve isolates an input port and connects an outlet port to an exhaust port when the fluid control valve is in its closed position. A system is provided for locking the fluid control valve in the closed position. The indicator device is used to provide an indication of the pressure within the outlet port to ensure safe operation.

Abstract: A directional control valve includes a pressure regulator piston configured as a hollow slide with a radial passage positioned in such a way that a connection from the internal chamber of the pressure regulator piston to a pump pressure annular channel (P) can be regulated by the radial passage and a second radial passage of a directional control valve piston. The second radial passage constitutes a control edge, which is used to regulate the connection from the internal chamber to a load sensing annular channel (LS). An annular groove, which in the neutral position forms a connection from the internal chamber to the load sensing annular channel (LS), is joined to the second radial passage. The pressure regulator is impervious to different flow forces caused by different mass fluxes and ensures that the hydraulic consumer is prevented from moving in the neutral position.

Abstract: A feed position of oil from an oil pump is changed to improve the machinability of an engine cylinder block. A plunger guide is obtained which attains improvement in pump pressure resistance and retention of magnetic efficiency. An oil feed port connected to an oil feed path on the oil pump side is formed in a front end face of a sleeve in an electromagnetic type oil control valve, while a drain port connected to an oil discharge path on a drain side is formed in a side face of the sleeve, whereby an oil feed path formed in the engine cylinder block is positioned coaxially with a mounting hole of the electromagnetic type oil control valve. Further, a bottom wall portion of the plunger guide is curved so that the pump pressure resistance can be improved without increasing the plate thickness of the plunger guide.

Abstract: A solenoid valve is provided which may be used to inject fuel into an internal combustion engine for automotive vehicles. The solenoid valve includes an armature and stator attracting the armature to open a fluid passage. The solenoid valve also includes a retaining nut and an end body. The retaining nut engages a housing to retain a hollow cylindrical stator casing in the housing. The end body is joined to the casing in alignment therewith to hold the stator within the casing without subjecting the stator to the pressure produced by the engagement of the retaining nut with the housing. This minimizes undesirable loads on the stator.

Abstract: A booster pilot valve operable at ultra low power levels is provided. The booster valve includes a moveable spool capable of directing a fluid flow to at least two different paths. The booster valve may be coupled to a piezotronic three-way valve, which controls the movement of the spool by redirecting a main fluid flow along different paths to create a force on the spool. The piezotronic valve is capable of actuation at very low power levels such as might be provided by a Profibus PA or other Bus system.

Abstract: A directional control valve which has a movable control piston (5) which separates two pressure chambers (6, 8) from each other in the valve housing interior, which pressure chambers can be subjected to control pressure in order to move the control piston (5) into axial positions corresponding to relevant switch positions of the valve in accordance with the difference in pressure prevailing between the control chambers (6, 8). An arrangement (29) acts on the control piston (5), produces an actuating force and prestresses the control piston for movement into an axial position corresponding to a desired predetermined position.

Abstract: A solenoid valve has a housing having work, pressure, and tank connectors. An armature is movably arranged in the housing and cooperates with a coil. A slide is moveably arranged in the housing and has a hydraulic chamber connected to the work connector and connectable to the pressure connector. A plunger is positioned between the armature and the slide. The armature acts on the plunger which acts on the slide for moving the slide against a counter force. The plunger has a cross-section and the slide has a piston surface cooperating with the plunger, wherein the cross-section is smaller than the piston surface. In another embodiment, the slide has a first end, loaded by a supply pressure of the pressure connector, and a second end, loaded by a return pressure, so that the slide is hydraulically tensioned by the supply pressure and the return pressure.

Abstract: A proportional, pilot-operated directional valve has a sleeve with at least four sets of radial holes, and a spool disposed within the sleeve, with a channel being defined between the spool and the sleeve. The spool has at least two sets of radial holes, and the exterior surface of the spool has annular protrusions, each being in at least partial contact with the inner wall of the sleeve. When the valve is in an open position, the first set of radial holes of the sleeve is in communication with one of the two sets of radial holes of the spool, the second and third sets of radial holes of the sleeve are each at least in partial communication with the channel, and the fourth set of radial holes of the sleeve is in communication with the other of the two sets of radial holes of the spool. The spool may be kept in an open position by pressure from a flow of fluid that is provided at one end of the sleeve.

Abstract: Since an output port is formed at a front end portion of a sleeve, an electromagnetic valve is arranged in series with a control valve. Thus, a system becomes small, and it becomes easy to attain a mounting space. Further, since a feedback chamber is formed in the vicinity of the linear solenoid, it is possible to install a spool after the sleeve is attached to the linear solenoid. Thus, unidirectional assembling becomes possible, and the number of assembling steps is decreased. Furthermore, since a small-diameter land is provided in the spool at a side of the linear solenoid, a small-diameter inner wall for slidably guiding the small-diameter land is concentrated to one place at the side of the linear solenoid. Thus, forming a small-diameter hole in the sleeve becomes easy, and forming accuracy is improved.

Abstract: A proportional, pilot-operated directional valve has a sleeve with at least four sets of radial holes, and a spool disposed within the sleeve, with a channel being defined between the spool and the sleeve. The spool has at least two sets of radial holes, and the exterior surface of the spool has annular protrusions, each being in at least partial contact with the inner wall of the sleeve. When the valve is in an open position, the first set of radial holes of the sleeve is in communication with one of the two sets of radial holes of the spool, the second and third sets of radial holes of the sleeve are each at least in partial communication with the channel, and the fourth set of radial holes of the sleeve is in communication with the other of the two sets of radial holes of the spool. The spool may be kept in an open position by pressure from a flow of fluid that is provided at one end of the sleeve.

Abstract: A recovery check valve 26 and a piston valve 27 are axially slidably disposed within a spool 2 in coaxial relation. An axial fluid passage 32 is formed within a cylindrical portion 27a of the piston valve 27, and a seat portion 33 for the recovery check valve is formed at an open end of the cylindrical portion 27a. The cylindrical portion 37a of the piston valve is formed with a hole 36 through which a hydraulic fluid in the fluid chamber 32 is introduced to a bridge passage 21 when the spool 2 is operated so as to introduce a hydraulic fluid from a hydraulic pump to the bottom side of a hydraulic cylinder. Fluid passages 40, 31 are formed within the spool so that a hydraulic fluid in the bridge passage 21 is introduced to the closed end of the piston valve through the fluid passages when the spool is operated in the opposite direction. With such a structure, the size of the valve apparatus can be set to the same size as the directional control valve not provided with the recovery check valve.

Abstract: A booster pilot valve operable at ultra low power levels is provided. The booster valve includes a moveable spool capable of directing a fluid flow to at least two different paths. The booster valve may be coupled to a piezotronic three-way valve, which controls the movement of the spool by redirecting a main fluid flow along different paths to create a force on the spool. The piezotronic valve is capable of actuation at very low power levels such as might be provided by a Profibus PA or other Bus system.

Abstract: A solenoid for a hydraulic valve has an armature chamber having chamber walls. A pole core forms one of the chamber walls and has an axial central bore. An armature is slidably arranged in the armature chamber. The armature has a central receptacle. An armature piston is arranged in the central receptacle of the armature and extends through the axial central bore of the pole core. The armature piston consists of a nonmagnetic material. The armature piston acts on a valve member when moved by the armature piston. The armature piston is a tubular member formed of a piece of planar sheet metal and has a radially outwardly projecting anti-stick disc that defines a minimal axial spacing between the armature and the pole core. The radially outwardly projecting anti-stick disc is formed as a monolithic part of the tubular member by parts of the sheet metal being bent radially outwardly relative to the tubular member.

Abstract: A hydraulic valve, especially for controlling a camshaft movement in a motor vehicle, is provided. A valve bushing is insertable from an end face thereof into the receiving bore of a housing. The valve bushing has an axially extending control bore into which a disk is pressed with press fit from the end face of the valve bushing. The valve bushing, on an exterior surface thereof and starting from the end face, is provided with a turned groove that is disposed remote from a pressure medium flow.

Abstract: In a check valve assembly and a valve assembly employing such a check valve assembly, a topping piston may be taken into contact with a main poppet to raise the main poppet from its seat. The main poppet is designed without significant area difference from the valve seat and the topping piston is actuated through a pilot valve, so that the process of raising the main poppet from the valve seat is controllable.

Abstract: A valve assembly for actuation of a user and a method for actuation of the valve assembly, wherein a supply throttle device and a drain throttle device may be actuated independent of each other, is disclosed. In the case of single-action users, the drain throttle device is actuated such that the open cross-section of the drain throttle is maximum upon attaining the desired volumetric flow of hydraulic oil, so that the energy losses in the drain conduit are reduced to minimum.

Abstract: A valve assembly for pressure adapted and volumetric flow adapted supply of at least one user may be supplied with hydraulic fluid or connected to a tank via two work ports of a continuously adjustable directional control valve. To the two work ports of the valve assembly a common pressure compensator is associated, the piston of which is guided in axial translation in an axial bore of the directional control valve spool, so that one of the two work ports may optionally be connected to the pump port upon suitable actuation of the directional control valve. At both end surfaces of the directional control valve spool and at the spring side of the pressure compensator piston, there acts a respective control pressure which, for example, corresponds to the highest system load pressure, the individual load pressure, or a pressure derived therefrom.