Patent · US Expired

Movement detector

US4212005A · kind A · utility

4Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 28, 1978
Grant dateJul 8, 1980
Priority date
Expiry dateJun 28, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B13/1654
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The invention relates to a movement detector, more particularly a sensor comprising a container partially filled with a liquid into which three electrodes extend. An input alternating signal is applied to two of the electrodes and an output signal amplitude modulated in accordance with movement of the liquid in the container, is detected from another two of the electrodes by means of a sensing circuit which includes a demodulator for detecting the amplitude modulation and a circuit arrangement which provides a container movement signal in response to successive peaks in the demodulated signal which are in excess of a given threshold value being spaced apart in time from one another by a time dependent upon the peak magnitudes of the demodulated signal.

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