Patent · US Expired

Circuit breaker including two magnetic coils and a positive temperature coefficient resistivity element

US6020802A · kind A · utility

2Cited by
28References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 2, 1998
Grant dateFeb 1, 2000
Priority date
Expiry dateApr 2, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H71/40
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A circuit breaker for interrupting the flow of electric current in a line includes a switch connected in series with the line, the switch having an open position and a closed position. At least one positive temperature coefficient resistivity element (PTC element) is connected in series with the line. A first magnetic coil is positioned around a yoke, for example, an iron core, and connected in parallel with the PTC element and a second magnetic coil is positioned around the yoke and connected in series with the line and the switch. A voltage limiting device, such as a metal oxide varistor, is connected in parallel with the at least one PTC element. An armature is pivotally mounted in relation to the yoke wherein the yoke and the armature form a magnetic circuit with the first magnetic coil and the second magnetic coil. A trip lever is connected to the armature and the switch, the trip lever effecting movement of the switch from a closed position to an open position wherein the flow of electric current in the line is interrupted. When the first magnetic coil or the second magnetic coil reaches a predetermined current value, the armature is pulled to trip by the magnetic circuit whe…

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