Patent 7393085 was granted and assigned to Videojet Technologies (company) on July, 2008 by the United States Patent and Trademark Office.
A method of operating a continuous ink jet printer apparatus, the method comprising the steps of: applying a first voltage pulse to an electrode in order to modify the direction of an ink stream; applying a second voltage pulse to the electrode for a pre-determined period of time; measuring the charge carried on the ink stream; and modifying the operation of the printer in response to the charge measured.