Jason K Singleton

US Patent:

60991011, Aug 8, 2000

Filed:

Apr 6, 1998

Appl. No.:

9/055868

Inventors:

Giuseppe Andre Maurelli - Lexington KY
Brant Dennis Nystrom - Lexington KY
Jason Edward Singleton - Lexington KY

Assignee:

Lexmark International, Inc. - Lexington KY

International Classification:

B41J 2195

US Classification:

347 7

Abstract:

The invention described in the specification relates to an apparatus and method for disabling an ink jet print head cartridge so that the disposable cartridge can not be refilled and used again. The method involves placing a monitoring and disabling device inside of the ink jet print head cartridge. When the print head has exceeded its useful life span, the disabling device disables the print head cartridge. The apparatus consists of a set of electrically charged capacitors, a small processor, ink sensors, and an extra long life miniature battery. A card containing the battery, processor and capacitors is placed in the ink jet print head cartridge. A sensor is placed in the bottom of each ink well of the cartridge. The processor periodically checks the level of ink in each inkwell. Once the processor determines that a specific inkwell has been empty for a certain period of time, the capacitors are discharged to the section of the nozzle plate corresponding to the expended inkwell.