Valve actuator, valve, and machine consisting thereof

A valve actuator comprising moving equipment arranged to cause a plug of said equipment to slide along a given axis between two end positions, making it possible in service for the plug to put an admission channel of the valve into communication with at least one outlet of said valve, the moving equipment comprising a core constrained to move in translation with the plug along the given axis, the actuator including a coil lying between two rings of ferromagnetic material, all three of which are secured to a frame of the actuator so as to surround the core, which itself carries two magnets mounted in opposition on the core level with the coil, a ring of ferromagnetic material lying between the two magnets that also lie between two other rings of ferromagnetic material,

• applying power to the coil causing one of the magnets carried by the core to be attracted and the other magnet to be repelled depending on the direction in which the coil is powered, co-operation between the pair of rings of the frame and a respective one of the pairs of rings of the core serving to lock the plug in each of its end positions when the coil ceases to be powered, the moving equipment also having at least two elastically deformable elements connected to the core in such a manner that the pairs of rings of the core are offset from the pair of rings of the frame while locking the plug in each of its end positions.