Michael J Rybicki

US Patent:

7347539, Mar 25, 2008

Filed:

Sep 24, 2004

Appl. No.:

10/949605

Inventors:

Michael J. Rybicki - Downers Grove IL, US
Andrew Earl Fickling - Mt. Prospect IL, US

Assignee:

Videojet Technologies Inc. - Wood Dale IL

International Classification:

B41J 2/085

US Classification:

347 76

Abstract:

Certain embodiments provide a system and method for auto-threshold adjustment using a continuous ink jet printer. An embodiment of a system includes a nozzle for producing ink drops from an ink stream, a sensor positioned with respect to the nozzle for measuring charge from the ink drops to generate a charge signal, a peak detector for detecting peaks in the charge signal, and a threshold storage device for adjusting the threshold based on a number of detected peaks. In an embodiment, the threshold storage device stores the threshold. The threshold storage device may be a digital potentiometer, for example. The system may also include a comparator comparing the charge signal to the threshold. The comparator may select between the threshold and a standard reference signal to compare to the charge signal.

US Patent:

60446943, Apr 4, 2000

Filed:

Aug 28, 1996

Appl. No.:

8/704116

Inventors:

Philip D. Anderson - Wood Dale IL
Michael J. Rybicki - Downers Grove IL

Assignee:

Videojet Systems International, Inc. - Wood Dale IL

International Classification:

G01N 1116

US Classification:

73 5441

Abstract:

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.