| 摘要 |
<p>PURPOSE:To make heat treatment needless for improving production efficiency in a manufacture line by reducing a varistor voltage change factor to the extent of being able to be put to practical use by impressing surge voltage at least of 5kV charged to the prescribed capacity. CONSTITUTION:Surge voltage is impressed on a nonohmic electrode given to the primary body surface so as to break an insulating layer for making the nonohmic electrode ohmic. Surge voltage of at least 5kV having small capacity, for instance, being charged to the capacity of 1000pF is impressed, for instance, five times. In this way, when surge voltage is at least 5kV, a varistor voltage change factor can be reduced to an extent able to be fully put to practical use under 5% of a varistor change factor without heat treatment. Accordingly, a varistor can be formed in a series of manufacture line so as to improve its production efficiency.</p> |
