The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 19, 2002
Filed:
Apr. 29, 2000
Stephen W Bauer, San Diego, CA (US);
Jeffrey D Rutland, San Diego, CA (US);
Grant A Webster, Valley Center, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
The present invention includes as one embodiment a method of controlling an inkjet printhead assembly, including providing the printhead assembly having ink ejection elements that eject ink from a firing chamber through a nozzle and being energizable by an electrical pulse having a first predetermined energy, monitoring the printhead assembly to determine elapsed time since each ink ejection element on the printhead assembly has been fired, calculating a predetermined maximum amount of time that an ink ejection element is not operating using ink formulation and geometry of the nozzle and the firing chamber, comparing the elapsed time for each ink ejection element on the printhead assembly with the predetermined maximum amount of time and initiating high energy spitting at a second predetermined energy for the printhead assembly if the predetermined maximum amount of time has been exceeded for at least one of the ink ejection elements on the printhead assembly.