Patent · US Expired

Micro-mechanical capacitive inductive sensor for wireless detection of relative or absolute pressure

US7024936B2 · kind B2 · utility

12Cited by
11References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 2003
Grant dateApr 11, 2006
Priority date
Expiry dateJul 9, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01L9/0073
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A micro-mechanical pressure transducer is disclosed in which a capacitive transducer structure is integrated with an inductor coil to form a LC tank circuit, resonance frequency of which may be detected remotely by imposing an electromagnetic field on the transducer. The capacitive transducer structure comprises a conductive movable diaphragm, a fixed counter electrode, and a predetermined air gap between said diaphragm and electrode. The diaphragm deflects in response to an applied pressure differential, leading to a change of capacitance in the structure and hence a shift of resonance frequency of the LC tank circuit. The resonance frequency of the LC circuit can be remotely detected by measuring and determining the corresponding peak in electromagnetic impedance of the transducer.

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