| 摘要 |
<p>A vacuum type circuit interrupter having a main arcing shield, surrounding the contacts, which is provided with arc inhibiting means preventing migration of the arc root along the external surface of the main arcing shield. In one embodiment of the invention an insulating coating is applied to the external surface of the main arcing shield to prevent arc movement. In another embodiment auxiliary end shields, which are supported from the main arcing shield, are disposed around the free ends of the main arcing shield preventing arc movement to the outer surface of the main arcing shield. Auxiliary end shields can either be directly attached to the main arcing shield or connected to the main arcing shield through insulating members. In another embodiment of the invention the main arcing shield, generally tubular shaped, has a circumferential groove formed around the main arcing shield near the end. This groove which can be either inwardly projecting or outwardly projecting with respect to the longitudinal axis of the vacuum interrupter limits migration of an arc from traveling along the outside surface of the main arcing shield. The various arc inhibiting means described can be used singly or in combination to restrict arc movement.</p> |
