Textured-surface quartz resonator fluid density and viscosity monitor

Patent 5798452 Issued on August 25, 1998. Estimated Expiration Date:

April 25, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

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Inventors

Assignee

Sandia Corporation

Application

No. 846085 filed on 04/25/1997

US Classes:

73/32RSPECIFIC GRAVITY OR DENSITY OF LIQUID OR SOLID

Examiners

Primary: Oda, Christine K.

International Class

G01N 009/00

Abstract

A pair of thickness-shear mode resonators, one smooth and one with a textured surface, allows fluid density and viscosity to be independently resolved. A textured surface, either randomly rough or regularly patterned, leads to trapping of liquid at the device surface. The synchronous motion of this trapped liquid with the oscillating device surface allows the device to weigh the liquid; this leads to an additional response that depends on liquid density. This additional response enables a pair of devices, one smooth and one textured, to independently resolve liquid density and viscosity; the difference in responses determines the density while the smooth device determines the density-viscosity product, and thus, the pair determines both density and viscosity.

Other References

Martin, et al. Measuring Liquid properties with Smooth-and Textured-Surface Resonators. Proceedings of the 1993 IEEE International Frequency Control Symposium, pp. 603-608, 2 Jun. 1993
Stephen J. Martin, et al., "Characterization of a Quartz Crystall Microbalance with Simultaneous Mass and Liquid Loading," Analytical Chemistry, vol. 63, No. 20, pp. 2272-2281 (1991