| 摘要 |
<p>An electric switch with a set of stationary contacts and a set of movable contacts situated on a contact bridge (30) between an IN-position and an OUT-position includes a forcibly guiding mechanism (32) for manual handling of the contact bridge (30) and an ejector mechanism (56) and a trip device (74) co-operating with the ejector mechanism, whereby the contact bridge (30) is automatically longitudinally displaced from its IN-position to its OUT-position when an overloading, a fault or a signal current is present. The forcibly guiding mechanism (32) and the contact bridge (30) are interconnected by means of a releasably blocking device in such a manner that the ejector mechanism (56) in the releasing state need only overcome frictional forces between the stationary and the movable contacts as the blocking device is released by means of the trip device (74). The forcibly guiding mechansim (32) and the ejector mechanism (56) co-operate in such a manner that the latter containing an energy reservoir such as a spring (64) is automatically reset before the contact bridge (30) can be forced to the IN-position. The forcibly guiding mechanism (32), in the form of an elbow joint, moves between two extreme positions and during such movement it passes a dead center. It includes a tilting spring (40) the potential energy of which after the passage of the dead center is utilized for charing the energy reservoir (64) of the ejector mechanism (56).</p> |
