The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 21, 1977
Filed:
Oct. 29, 1975
Hitachi, Ltd., , JA;
Abstract
Spark gap apparatuses are provided at the receiving end or the sending end of an electric power substation, in order to protect electric apparatus in the electric power substation against the surge voltage incoming from the power transmission lines. In the case where the gap of such a spark gas apparatus is placed in electronegative gas, for example SF.sub.6 gas, the spark voltage vs. spark time characteristic varies depending on the polarity of the surge voltage and thus the protecting performance of the spark gap apparatus is poor. The improvement in the protecting performance of the spark gap apparatus is provided by substantially equilizing the maximum electric field developed between the end surfaces of a pair of electrodes which are oppositely disposed to each other to form a spark gap therebetween.