Machine fluid sensor and method

• US 7,043,969 B2
• Filed: 06/02/2003
• Issued: 05/16/2006
• Est. Priority Date: 10/18/2002
• Status: Expired due to Term

• Current Assignee: Meas France
• Original Assignee: Symyx Technologies Incorporated (Dassault Systemes SA)
• Inventors: Bennett, James, Spitkovsky, Mikhail, Pinkas, Daniel M., Varni, John F., Dales, G. Cameron, Matsiev, Leonid, Kolosov, Oleg, Guan, Shenheng, Padowitz, Dave, Low, Eric, Gammer, Vladimir, Uhrich, Mark, Walker, Blake
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): FITZGERALD, JOHN P
• Application Number:
  US10/452,264
• Publication Number:
  US 20040099050A1
• Time in Patent Office: 1,079 Days
• Field of Search: 73/240.6, 73/310.6, 73/300.4, 73/32.A, 73/542.4, 73/543.8, 73/544.1, 73/614.9, 73/617.5, 422/68.1
• US Class Current: 73/54.41
• CPC Class Codes: F02D 2200/0611 Fuel type, fuel composition or fuel quality
• CPC Class Codes: F02D 2250/11 Oil dilution, i.e. prevention thereof or special controls according thereto
• CPC Class Codes: F02D 41/021 Introducing corrections for particular conditions exterior to the engine conjoint control of vehicle sub-units for propelling the vehicle B60W30/18
• CPC Class Codes: G01F 23/2966 making use of acoustical resonance or standing waves
• CPC Class Codes: G01N 11/16 by measuring damping effect upon oscillatory body
• CPC Class Codes: G01N 2291/014 Resonance or resonant frequency
• CPC Class Codes: G01N 2291/0226 Oils, e.g. engine oils
• CPC Class Codes: G01N 2291/02416 Solids in liquids
• CPC Class Codes: G01N 2291/02818 Density, viscosity
• CPC Class Codes: G01N 2291/02836 Flow rate, liquid level
• CPC Class Codes: G01N 2291/0422 Shear waves, transverse waves, horizontally polarised waves
• CPC Class Codes: G01N 2291/0423 Surface waves, e.g. Rayleigh waves, Love waves
• CPC Class Codes: G01N 2291/0426 Bulk waves, e.g. quartz crystal microbalance, torsional waves
• CPC Class Codes: G01N 2291/0427 Flexural waves, plate waves, e.g. Lamb waves, tuning fork, cantilever
• CPC Class Codes: G01N 29/022 Fluid sensors based on microsensors, e.g. quartz crystal-microbalance [QCM], surface acoustic wave [SAW] devices, tuning forks, cantilevers, flexural plate wave [FPW] devices microdevices per se B81B
• CPC Class Codes: G01N 29/036 by measuring frequency or resonance of acoustic waves
• CPC Class Codes: G01N 29/30 Arrangements for calibrating or comparing, e.g. with standard objects
• CPC Class Codes: G01N 29/348 with frequency characteristics, e.g. single frequency signals, chirp signals measuring frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04; measuring frequency or analysing frequency spectra G01R23/00
• CPC Class Codes: G01N 9/002 using variation of the resonant frequency of an element vibrating in contact with the material submitted to analysis G01N9/34 takes precedence

Abstract

A method for analyzing a fluid contained within a machine, comprising the steps of providing a machine including a passage for containing a fluid; placing a sensor including a mechanical resonator in the passage; operating the resonator to have a portion thereof translate through the fluid; and monitoring the response of the resonator to the fluid in the passage. A preferred sensor includes a tuning fork resonator.

Claims

1. A method for analyzing a fluid contained within a vehicle, the method comprising the steps of:

a) operating a tuning fork resonator at a frequency of less than 1 MHz while the resonator is in contact with said fluid contained within said vehicle; and

b) monitoring a response of the resonator.

2. The method of claim 1 wherein said monitoring step comprises monitoring the change of frequency of the tuning fork resonator while maintaining an input signal to the resonator as a constant.

3. The method of claim 1, wherein said monitoring step comprises monitoring a change in electrical feedback from the tuning fork resonator.

4. The method of claim 1, further comprising operating said tuning fork resonator in a non-resonant mode wherein at least a portion of the tuning fork resonator is translated through said fluid.

5. The method of claim 1, wherein the response is at least related to the viscosity of the fluid.

6. The method of claim 1, wherein the vehicle is an automotive vehicle.

7. The method of claim 1, wherein the tuning fork resonator is located in an engine oil pan of the vehicle.

8. The method of claim 1 further comprising the step of mounting a sensor comprising said tuning fork resonator on the vehicle.

9. The method of claim 1, wherein the operating step comprises applying a variable frequency input signal to the tuning fork resonator.

10. The method of claim 9, wherein said operating step further comprises varying the frequency of the input signal over a predetermined frequency range, and wherein said monitoring step comprises obtaining a frequency-dependent resonator response of the tuning fork resonator.

11. The method of claim 1 wherein the resonator comprises a resonator element made of a material selected from piezoelectric materials, electrostrictive material, magneto restrictive materials, piezoresistive materials, elasto-optic materials, anisotropic material, or combinations thereof.

12. The method of claim 11, wherein the monitoring step comprises monitoring a response of the tuning fork resonator while the resonator is located in a temperature controlled region.

13. The method of claim 11, wherein said resonator element comprises a piezoelectric material.