Magnetic actuator with short response time

Magnetic actuator having a closed magnetic circuit (26) capable of guiding a magnetic flux, this magnetic circuit (26) comprising a fixed magnetic part (30, 31, 32) with a yoke (30) and a mobile magnetic part (22), magnetically connected to each other and also at least one main air gap (29) delimited by at least one portion (28) of the mobile magnetic part (22) and by the yoke (30), in which the magnetic flux is closed by being set up approximately transverse to the mobile magnetic part (22), characterised in that the fixed magnetic part (30, 31, 32) comprises flux recuperation means (40) that contribute with the mobile part (22) to delimiting an auxiliary air gap (38) in which the magnetic flux is set up laterally to the mobile part (22), the magnetic flux being contained on each side of the main air gap (29), on one side by the yoke (30), and on the other side jointly by the mobile part (22) and the flux recuperation means (40) through the part (28) contributing to delimiting the main air gap (29), the dimension of the auxiliary air gap (38) in the direction in which magnetic flux is set up being a minimum in at least one area of the portion (28) contributing to delimiting the main air gap (29).