Patent · US Expired

Signal decision system

US4165458A · kind A · utility

21Cited by
5References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 14, 1977
Grant dateAug 21, 1979
Priority date
Expiry dateApr 14, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V1/001
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An electrical signal originating from an abnormal sound is passed through a bandpass filter and compared with a reference signal by a comparator. When the electrical signal is not less than the reference signal, the comparator produces a pulse. A counter counts the pulses from the comparator and causes a display device to display the presence of the abnormal sound when its count exceeds a predetermined value within a predetermined time interval.

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