Patent · US Expired

Thermally responsive electrical control device and monitoring circuit therefor

US4576487A · kind A · utility

15Cited by
6References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 23, 1984
Grant dateMar 18, 1986
Priority date
Expiry dateJan 23, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01K3/005
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A thermally responsive electrical control device is operable for producing a control signal having first and second voltage levels for controlling the operation of a system actuating device for first and second modes of operation. One embodiment of the device includes a multiple bridge circuit for sensing two temperatures and for making multiple control decisions in response to the two temperatures. Another embodiment of the device includes a thermistor and a nonlinear variable resistance element which is matched in a substantially linear relation with the thermistor for compensating for the inherent substantially nonlinear character of the thermistor. Still another embodiment of the device includes a monitoring circuit which is interconnected to a bridge circuit of the device for providing visual indications of sensed temperatures without significantly interrupting the control function of the device.

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