Patent · US Expired

Acoustical switch

US3970987A · kind A · utility

34Cited by
6References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 31, 1974
Grant dateJul 20, 1976
Priority date
Expiry dateMay 31, 1994

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S1/72
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An acoustical switch is actuated from a remote location by a sound generator such as an ultrasonic whistle. The switch includes a special tuned signal receiver coupled with an amplifier having a frequency selective feedback network. The output of the amplifier is an a.c. signal which is applied to a bistable circuit which, in one state, energizes a relay to turn on an appliance connected to the switch and, in its other state, turns the appliance off.

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