Title:
【発明の名称】同一周波数発生器及びFFTによる流体特性及び流量検知
Document Type and Number:
Japanese Patent JP2002500355
Kind Code:
A
Abstract:
A method for determining a property of a fluid of interest comprises the following steps:energizing a heater (402) and a first sensor (404) with at least two timevarying input signals, each having a different frequency, wherein the heater (402) and the first sensor (404) are thermally coupled to the fluid of interest and have a resistance that change with temperature;sensing the resistance change of the first sensor;determining a lag between selected ones of the at least two time-varying input signals and the corresponding resistance change of the first sensor; anddetermining a first ideal input frequency that would produce a phase lag between an ideal time-varying input signal and the resistance change of the first sensor that substantially equals a first calibrated phase lag value.
Inventors:
Kubisiak, David
Bonn, Ulrich
Bonn, Ulrich
Application Number:
JP2000526799A
Publication Date:
January 08, 2002
Filing Date:
December 03, 1998
Export Citation:
Assignee:
Honeywell Incorporated
International Classes:
G01F1/684; G01F1/698; G01F1/7084; G01F1/712; G01F5/00; G01N25/18; G01N27/18; (IPC1-7): G01N25/18; G01F1/698; G01N27/18
Domestic Patent References:
| JPS4970672A | 1974-07-09 | |||
| JPH08136596A | 1996-05-31 |
Attorney, Agent or Firm:
Kazuo Shamoto (5 outside)