Electromagnetic switchgear comprising a magnetic drive and a contact apparatus placed thereabove

Electromagnetic switchgear comprising a magnetic drive having a yoke which contains a permanent magnet arrangement and surrounds a coil form whose continuous bore contains an armature which, by means of a reverse-transfer lever, actuates an adjusting slider mounted with allowance for sliding in a contact apparatus placed above the coil form parallel to the longitudinal axis thereof, the adjusting slider being in operative connection with two return springs preloaded in opposite directions, and carrying spring-loaded bridge contacts to each of which are assigned two opposed fixed contacts, characterized in that said coil form is subdivided into two spaced-apart chambers arranged side by side which receive corresponding coil windings, that said permanent magnet arrangement lies symmetrically to the longitudinal axis of said coil form between said two chambers, is polarized at right angles to the longitudinal axis of the coil former, and has a through-opening for said armature which corresponds substantially to the diameter of the bore of the coil form, said armature being mounted on a non-magnetic guide bar and having two end faces which cooperate with the pole faces of the yoke located in the area of the end openings of the bore of the coil form, and that the adjusting slider is in operative connection with both return springs only in its geometric middle position, but upon leaving said middle position stresses only one of the return springs.