ELECTROMAGNETIC ACTUATOR HAVING A HIGH UNLOCKING FORCE

摘要

The invention relates to an electromagnetic trigger of the differential relay type comprising: a U shaped armature (1) the ends of the two legs (4 5) of which form two coplanar polar surfaces; a pivoting plate (2) that pivots between two positions in which it respectively is at distance i.e. there is a gap between it and said armature (1) and in the armed position of the trigger it makes contact with said polar surfaces and thus closes the magnetic circuit formed by said armature (1) and said plate (2) the hinge (3) of the plate (2) being located in the immediate vicinity of the end of one of the legs (4) of the armature (1); a permanent magnet (6) for biasing the magnetic circuit placed between the legs (4 5) of the armature (1) and creating a permanent magnetic force attracting the plate (2) toward the polar surfaces which magnetic force acts against a return force exerted by a spring (13); and an inductive coil (16) encircling the magnetic circuit connected for example to a circuit to be controlled with a view to modifying the initial balance between the magnetic force and the return force of the spring (13). The magnet (6) is positioned in the vicinity of the leg (5) of the armature (1) opposite the leg (4) proximate the hinge (3) of the plate (2).