Abstract: The invention relates to a valve having a housing in which there is a passage having at least two spaced ports. A slide is accommodated in the passage for to and fro movements between at least two positions in one of which at least one of the ports is open and in the other of which such port is closed. A slide actuator effects movements of the slide and the slide carries a seal which effects a seal of the closed port when the slide is in the port-closing position. The seal has a sealing actuator operable separately from the slide actuator to apply a sealing force to the seal. The force applied to the seal is neutralized in response to actuation of the slide.

Abstract: A method of producing an electromagnetic coil comprises winding a length of electrically conductive wire about a non-conductive tubular body having electrically conductive pins embedded therein, coupling opposite ends of the wire to the respective pins, and embedding the pins more deeply in the body following the coupling of the opposite ends of the wire to such pins.

Abstract: The invention relates to an electromagnetic valve having a passage therethrough and a closure member which is reciprocable between first and second positions in whoch the passage is openend and closed. An electromagnectic controllable actuator effects movement of the closure member against a spring force from the first position into the second position. The valve includes a retainer which retains the closure member in the second position. The retainer is formed by a piezoelectric bending element which locks the closure member positively in the second position.