| 摘要 |
PURPOSE:To decrease bursting noise and enhance impact resistance by interposing a different kind of insulating material between a conductive container and a current limiting element, and providing bursting holes in the container and the insulating material. CONSTITUTION:Bursting holes 1a are provided in a side wall of cylindrical conductive container 1, and a current limiting element 2 and a high voltage side electrode 3 are housed inside the container 1. Outside circumferences of the current limiting element 2 and the electrode 3 are covered by insulating materials 5 and 6 having bursting holes 5a, and the whole of the container 1 is covered by an insulating material 7. With this constitution, when an internal arc is generated by a lightning surge and the like excuding a design value, the current limiting element 2 and the electrode 3 are protected by the insulating material 5. The internal arc is blown out through the bursting hole 5a, and the arc is not discharged outside but is continued in short passages between the hole 5a and the conductive container 1. Accordingly, the arc is limited within arc generation between the current limiting element 2 and the container 1, bursting noise is decreased, and durability is retained. |
