Abstract: A control device for a movable contact relative to a fixed contact of a vacuum bottle of an electrical switching device. The control device includes a principal mechanism for disconnection and connection of the contacts, of the mechanical energy accumulation type. The control device further includes an auxiliary disconnection-assistance mechanism arranged such as to accumulate mechanical energy when the movable contact is moved towards the connection position and such as to restore the mechanical energy thus accumulated in such a manner as to exert an additional disconnection force in the form of an impact tending to move the movable contact from the connection position towards the disconnection position when the movable contact is immobilized in the connection position despite the action of the principal disconnection force.

Abstract: A control device for a movable contact relative to a fixed contact of a vacuum bottle of an electrical switching device. The control device comprises a principal mechanism for disconnection and connection of the contacts, of the mechanical energy accumulation type. The control device further comprises an auxiliary disconnection-assistance mechanism arranged such as to accumulate mechanical energy when the movable contact is moved towards the connection position and such as to restore the mechanical energy thus accumulated in such a manner as to exert an additional disconnection force in the form of an impact tending to move the movable contact from the connection position towards the disconnection position when the movable contact is immobilized in the connection position despite the action of the principal disconnection force.

Abstract: A switch comprises a long, slender stationary contact means and a movable contact means moving between an open position and a closed position. The contact zone of the contact means is separated from the electrical connection zone by a slot which opens out on the side where the movable contact means are situated in the open position. The depth of the slot is sufficient so that, when opening takes place, the current lines passing through the contact means are curved and run approximately parallel to the flank of the slot. This arrangement prevents the foot of the electrical arc from being directed towards the free end of the contact means, away from the arc extinguishing chamber.

Abstract: A selective magnetic trip unit comprises a fixed magnetic armature located facing a movable magnetic armature and a damping device with a blade mounted on the movable magnetic armature. The damping device is designed to be in an inactive state up to an intermediate non-tripping position when the movable magnetic armature is attracted by polar parts of the fixed magnetic armature during a first travel, switching to the active state resulting from a deformation of the damping device during a second travel of the movable armature between the intermediate position and the final attraction position causing tripping of the circuit breaker.