Patent · US Expired

PTC element

US5382938A · kind A · utility

117Cited by
8References
47Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 25, 1991
Grant dateJan 17, 1995
Priority date
Expiry dateOct 25, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H3/025
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A PTC element has at least one body and two electrodes. The body or bodies has/have and is/are two parallel surfaces, of an electrically conductive polymer composition with a positive temperature coefficient. At least one of the parallel surfaces on the body, or on one of the bodies, of polymer composition is in free contact with an electrode or with a parallel surface on another body of electrically conductive polymer composition. A pressure device exerts a pressure directed perpendicularly to the parallel surfaces on the body, or the bodies, on the electrodes. The pressure device is preferably provided with pressure-exerting devices with the ability to be resilient. After changing from a low resistance to a high resistance state, the PTC element returns to the initial resistance and is reusable after having been subjected to short-circuit currents. The parallel surfaces on the body, or the bodies, of polymer composition may be concentric.

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