摘要 |
<p>An electric switching device comprises a quick mechanical electric switch and an irradiation source and at least one switching element sensitive to irradiation and adapted to create an electrically well conducting current path by-passing the electric mechanical switch upon irradiation thereon through the irradiation source, but assuming an electrically insulating state in absence of irradiation thereon. The quick mechanical electric switch is capable of being quickly de-ionized after extinction of an electric arc created therein upon separation of the contacts of the mechanical switch.</p> |