06044694 is referenced by 63 patents and cites 22 patents.

Resonator sensors namely piezoelectric benders are used for sensing fluid viscosity and density. The benders are inserted into a liquid to be monitored. An input voltage is applied to the bender causing it to vibrate in the liquid at a resonant frequency. Output voltage amplitude or frequency are monitored to determine changes in viscosity and density, respectively. The device may be used as a liquid level sensor and to control alteration of the viscosity of the fluid as, for example, by connection with a supply of ink or solvent in an ink jet printing device.

Title
Resonator sensors employing piezoelectric benders for fluid property sensing
Application Number
8/704116
Publication Number
6044694
Application Date
August 28, 1996
Publication Date
April 4, 2000
Inventor
Michael J Rybicki
Downers Grove
IL, US
Philip D Anderson
Wood Dale
IL, US
Agent
Piper Marbury Rudnick & Wolfe
Assignee
Videojet Systems International
IL, US
IPC
G01N 11/16
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