Electromagnetic actuator and switch apparatus equipped with such an electromagnetic actuator

An electromagnetic actuator for a switch apparatus, comprising a fixed part, a moving part and an excitation coil,

• the fixed part comprising a ferromagnetic yoke and a magnetized assembly of at least one magnet fixedly mounted on the yoke, the magnetized assembly extending in a direction substantially parallel to an axis of movement of the moving part,
• the moving part comprising a ferromagnetic element comprising a first air-gap surface for forming a magnetic air-gap of variable thickness from the ferromagnetic yoke, and a second air-gap surface for forming a residual magnetic air-gap of substantially constant thickness from the fixed part, said second air-gap surface being substantially parallel to the axis of movement of the moving part,
• the excitation coil enabling the position and speed of the moving part to be controlled by an electric control current,
• wherein the magnetized assembly faces the second air-gap surface so that, whatever the position of the moving part, the residual magnetic air-gap is always between the second air-gap surface of the ferromagnetic element of the moving part and a corresponding air-gap surface of the magnetized assembly, and the at least one magnet of the magnetized assembly is on a face of the ferromagnetic yoke and extends substantially over the entire dimension of said face parallel to the axis of movement.