Patent ID: 8169284

Claim:
An electromagnetic actuator, having an actuating member associated with an armature and capable of moving under an action of at least one electromagnet, comprising: a coil; a core designed to channel a flux of the coil so as to form a return path in the armature, the core having a base from which branches extend, including a central branch around which the coil extends; and two permanent magnets which are associated with the core so that the core channels the flux of the permanent magnets so as to form a return path in the armature, the flux of the coil passing through the magnets, wherein the two permanent magnets are placed in the central branch of the core so as to form a V, which separates the central branch into a support part, which supports the permanent magnets and is integral with the base, and an end part lying above the permanent magnets, and wherein critical sections of the core or of the armature through which the flux of one or another of the permanent magnets passes, comprise: first critical sections extending in the end part between one end of the permanent magnets and a central axis X; and second critical sections, each second critical section extending in one of the support part between another end of the corresponding permanent magnets and an angle formed by the base and the support part, wherein an upper limit is given to ratios between an area of a surface of the permanent magnet, such surface being in contact with the core, and an area of said first and second critical sections, said upper limit of the ratios depending on a material used for the core and for the armature.