Patent · US Expired

Interactive overvoltage protection device

US4625255A · kind A · utility

6Cited by
3References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 23, 1984
Grant dateNov 25, 1986
Priority date
Expiry dateApr 23, 2004

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H9/06
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An overvoltage protection device, especially for telephone equipment and the like, comprises two protectors connected directly in parallel. One protector, for example a back-to-back semiconductor diode, has a breakdown voltage below which it is a high impedance. Between the breakdown voltage and a failure voltage it has a lower impedance. Above the failure voltage it has negligible impedance. The other protector, for example a gas tube, has a range of operating voltages which extends from below the breakdown voltage of the diode, to a voltage between the breakdown voltage and the failure voltage of the diode. In operation the two protectors interact, the diode operating, for example, on faster surges and, in so doing, slowing the surge front so as to increase the likelihood that the gas tube will fire.

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