Patent ID: 6481823
Filing Date: 2002-11-19
Classification: B41J

Abstract:
A method of controlling an inkjet printhead assembly, comprising: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.