Patent · US Expired

Current-limiting resistor having PTC behavior

US5861795A · kind A · utility

6Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 27, 1997
Grant dateJan 19, 1999
Priority date
Expiry dateFeb 27, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01C13/02
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The current-limiting resistor has two connection electrodes (1, 2) which are arranged parallel to one another as well as a resistance body (3) which has PTC behavior and with which large-area contact is made by the connection electrodes (1, 2). A varistor (40) is in electrically conductive contact with the resistance body (3). The resistance body (3) contains two contact areas (50, 51) as well as a response point (60) which is connected in parallel with the varistor (40) via the two contact areas (50, 51) and implements a PTC transition above a threshold value of a current flowing through the resistor. Since the resistance body effects the electrical contact with the varistor (40) in the case of this resistor, no metal connection electrodes are required for the varistor. At the same time, due to the outward displacement of the response point (60) away from the varistor (40), the operational reliability of the resistor is considerably improved. Effective current limiting in load circuits which are operated at high voltage can be achieved by a series circuit formed by a plurality of varistors (40, 41, . . . ) provided in a resistance body (3) which is designed in the form of a meande…

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