Patent · US Expired

High-voltage variable resistor unit

US5508678A · kind A · utility

10Cited by
4References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 24, 1995
Grant dateApr 16, 1996
Priority date
Expiry dateJan 24, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01C10/32
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A high-voltage variable resistor unit including a variable resistance circuit board and a fixed resistance circuit board, and capable of being down-sized and exhibiting satisfactory dielectric strength. A variable resistance circuit board which is provided on a front surface thereof with a variable resistance circuit pattern is received in a board receiving chamber of an insulating casing. A lid member made of an insulating resin material is arranged so as to close an opening of the board receiving chamber while keeping a front surface thereof facing a rear surface of the variable resistance circuit board. A fixed resistance circuit board is fixed on a rear surface of the lid member while keeping a rear surface thereof facing the rear surface of the lid member. A space for charging an insulating resin material therein is defined between a circuit board and the rear surface of the lid member. The lid member is provided on the rear surface thereof with both a creeping distance increase recess and a creeping distance increase projection in a manner to surround the circuit board.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.