Patent · US Expired

Acoustical volume/pressure measurement device

US4704902A · kind A · utility

29Cited by
3References
12Claims
0Family size

Inventor

Key dates

Filing dateJul 10, 1986
Grant dateNov 10, 1987
Priority date
Expiry dateJul 10, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01F17/00
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The apparatus consists of a mechanical acoustical driver producing sound vibrations in a fluid, such as a liquid or gas, within an enclosed space. A pickup transducer positioned within the tank measures the sound vibrations of the gas within the tank and transmits the same to an amplifier and a low pass filter. Either the same or another transducer positioned in the tank measures static pressure P output of which is amplified. A divider circuit receives the dynamic pressure signal and static pressure signal and provides electrical signal E proportional to (.DELTA.P/P). A differential amplifier receives the reference signal Erf and the signal E and supplies the error signal (Erf-E) to a gain controlled amplifier. The gain controlled amplifier amplifies the AC signal proportional to (Erf-E). The driver generates .DELTA.P in the tank proportional to the output of the gain controlled amplifier.

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