Abstract: An electromagnetically-actuated two-way two-position valve is normally closed and comprises an axially-mobile group (5) which has an upper end (5a) that faces a fixed group (6) and which is attracted thereby. An obturator (4) is intercepted and then drawn in an opening movement by the mobile group (5) when the mobile group (5) is at a short distance from an end of its run. A return spring (9), which displaced the obturator (4) towards a closed position when the fixed group is deactivated, is entirely located behind the upper end (5a) of he mobile group (5). An air gap (8) is comprised, in a radial direction, between a coil (7) for activating the fixed group (6) and the upper end (5a) of the mobile group (5). The valve is constructionally simple and economical and has a higher fatigue resistance than known valves.

Abstract: An electromagnetically-actuated two-way two-position valve is normally closed and comprises an axially-mobile group (5) which has an upper end (5a) that faces a fixed group (6) and which is attracted thereby. An obturator (4) is intercepted and then drawn in an opening movement by the mobile group (5) when the mobile group (5) is at a short distance from an end of its run. A return spring (9), which displaced the obturator (4) towards a closed position when the fixed group is deactivated, is entirely located behind the upper end (5a) of he mobile group (5). An air gap (8) is comprised, in a radial direction, between a coil (7) for activating the fixed group (6) and the upper end (5a) of the mobile group (5). The valve is constructionally simple and economical and has a higher fatigue resistance than known valves.

Abstract: The valve described herein comprises a movable core (28) which is drawn toward a fixed core (21) once the valve is opened by excitation of its coil, or solenoid (24). The valve's needle-obturator (17) is capable of moving axially with respect to the movable core (28) but, upon the coil's being excited, remains thrust into the orifice (16) during a first opening stage while the movable core only (28) is caused to rise. Subsequently--once the movable core (28) arrives within a few millimeters of the fixed core--a shoulder (51) offered by the movable core to a shoulder (18) incorporated in the obturator (17) duly makes contact and draws the latter upward, whereupon the action of a spring (27) overcomes such resistance as is offered by a further spring (19) and the obturator itself (17) is raised to a generous distance from its seat in orifice (16) aforesaid.