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:
Jul. 10, 1990
Filed:
Dec. 16, 1988
NGK Insulators, Ltd., , JP;
Abstract
In case of manufacturing a voltage non-linear resistor, a sintering process is divided into two completely separate steps, i.e. primary and secondary sinterings. The primary sintering is carried out under a reduced pressure and the second sintering is conducted under an atmospheric pressure with a sufficient amount of oxygen. The primary sintering is effects such that the relative density and open porosity of the primarily sintered body are 85% or more and 1% or less, respectively. The secondary sintering removes to a large extent, voids existing in the body and, oxidation of the body is sufficiently effected. Therefore, the finally sintered body has a high density, a large surge withstanding capability, and a high non-linearity index.