A bistable hydraulic solenoid valve has a valve spool that transitions between two positions, remaining in one of the two positions under an attractive magnetic force when the solenoids are not energized. The valve spool has a first permanent magnet attached to one end and a second permanent magnet attached to the other end, so that the first permanent magnet faces a first solenoid, and the second permanent magnet faces a second solenoid. The first solenoid is energized to have a first polarity, and the second solenoid is energized to have an opposite polarity to concurrently push and pull the valve spool within the valve body between a first position and a second position, the first position establishing a first flow path and the second position establishing a second flow path through the valve body and valve spool so as to enable flow of hydraulic fluid.

Provided is a piezoelectric actuator that can reduce a risk of air leakage due to weakening of pressing force of a valve element against a valve seat surface and airtightness. The piezoelectric actuator is used for a piezoelectric valve that opens and closes a valve utilizing displacement of a laminated piezoelectric element. The piezoelectric actuator includes: a valve element; a laminated piezoelectric element that generates a driving force, required for operation of the valve element, as a displacement; and a displacement enlargement mechanism that enlarges a displacement of a laminated piezoelectric element and causes the enlarged displacement to act on the valve element. In the piezoelectric actuator, a surface of the valve element to be in contact with a valve seat of the piezoelectric valve is made flat and smooth in a state in which a tensile load is applied to the laminated piezoelectric element.

A translating actuator acting between two extreme positions defined by mechanical stops is described. Said actuator comprises: an armature mass movable relative to the armature body, a stiff armature spring set such that the natural resting position of the armature mass is close to the centre of travel between the two extreme positions and pair of latches with sufficient holding force that the armature mass can be held at either extreme position against the restoring force of the spring and can be released quickly relative to the natural period of vibration determined by the armature mass on the armature spring.

A valve (10) including a first port (12), a second port (14), a third port (16) and a flexure (30), the flexure (30) being moveable between a first position which causes the first port (12) to open, a second position which causes the second port (14) to open, and a third position which causes the first and second ports (12, 14) to close, wherein at least a part of the flexure (30) is magnetisable, to provide a first magnet (32), a second magnet (34) is associated with the first port (12) and a third magnet (36) is associated with the second port (14). A valve assembly includes a pair of valves wherein only one of the valves is operable at any given time.

The present disclosure relates to an improved pilot valve assembly for a hydrant pit valve. The pilot valve assembly includes a poppet that is movable between an open position and a closed position. The poppet has a molded seal with an interlock feature to hold the seal rigidly. The pilot valve assembly also includes a manually reset mechanism. The reset mechanism can be horizontally positioned and can function to reset the pilot actuator for the next refueling operation. A lanyard can be connected to the poppet to be used a deactuation mechanism.

A method for filling and venting a device for extracorporeal blood treatment is disclosed, such as a patient module in a heart-lung machine, without attached patient. A filling liquid from a filling liquid container located higher than the device flows by gravity via a venous side of the system into a reservoir and flows onwards into a blood pump located at the lower end of the reservoir, wherein a first controllable valve (HC1) for a venting line of a filter is opened and, after the response of an upper filling level sensor in the reservoir, is closed. An upper level of the filter is positioned higher than the upper filling level sensor, and a start-stop motion of the blood pump is performed, as a result of which a stepped flooding of the filter is made providing for an advantageous de-airing of the device.

The invention relates to a constant-pressure valve (45), in particular for an alarm valve station (100) of a sprinkler system (200), having a fluid inlet (16), a fluid outlet (15), a flow channel between the fluid inlet and the fluid outlet, and a control piston (3, 8) which is arranged in the flow channel and which is movable back and forth between a standby position and a triggering position and which has a first piston surface (S.sub.1) facing toward the flow channel and has a second piston surface (S.sub.2).

It is proposed according to the invention that the constant-pressure valve has a switching chamber which is separate from the flow channel and which has a switching pressure inlet (4) in fluid communication with the switching chamber, wherein the second piston surface (S.sub.2) faces toward the switching chamber (4a), wherein the constant-pressure valve (45) has a securing element (21) which is coupled to the control piston (3, 8) of the constant-pressure valve (45) and which, in the standby position, absorbs the forces acting on the first piston surface (S.sub.1) of the control piston (3, 8).

A bistable electromagnetic actuator includes a housing extending along an exertion axis of the actuator, two excitation coils arranged inside the housing and having at least one winding around the exertion axis for generating a magnetic control flux, a core that can be moved along the exertion axis and immobilized in two end positions depending on the magnetic flux generated by the coils, an actuating member coupled to the core to form a movable assembly, and a manual control device comprising a drive shaft mounted such that it can rotate about a first axis orthogonal to the exertion axis.

The drive shaft has at least one tooth engaging with at least one first raised part translationally connected to the actuating member such that rotation of the drive shaft generates translational movement of the movable assembly.

A bistable valve. The valve includes an interior cavity; a first pressure source; a second pressure source; a first post connected to the interior cavity at a first end of the interior cavity; a second post connected to the interior cavity at a second end of the interior cavity; a magnetic shuttle located within the interior cavity; a first electromagnetic coil disposed about the first post; a second electromagnetic coil disposed about the second post; wherein when the first electromagnetic coil is energized, the first electromagnetic coil supplies a magnetic charge to the first post and actuates the magnetic shuttle to move towards the first end of the interior cavity towards the first post and seal the first pressure source.

A shut-off valve that has a closure orifice, a closure member to open and close a gas passage through the shut-off valve, an electromagnetic actuator including a movable assembly attached to the closure member, the closure member, and an electromagnetic filed generator magnetically associated with the movable assembly. The shut-off valve also includes a manual actuator for acting on the movable assembly, the manual actuator comprising an open position in which it is decoupled from the movable assembly, the electromagnetic actuator thus being able to act on the closure member to cause its closure.