Patent · US Expired

Apparatus for and method of detecting a malfunction of a controller

US5249119A · kind A · utility

7Cited by
7References
10Claims
0Family size

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Key dates

Filing dateApr 25, 1991
Grant dateSep 28, 1993
Priority date
Expiry dateApr 25, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B9/02
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

An deviation E between a setting value SV and an actual phase value PV in a controller is integrated, and the resulting integrated value S is compared with a predetermined threshold D for detecting a malfunction. Checking a change in setting value SV, checking an increase or a decrease in deviation E and comparison with the absolute value .vertline.E.times.S.vertline. are made to ensure stability against fluctuations and rapid detection of a malfunction.

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