Patent ID: 7857409
Filing Date: 2010-12-28
Classification: B41J

Abstract:
1. An ink jet printing apparatus for performing a printing operation by scanning a print head including a plurality of print elements for ejecting ink, comprising: obtaining means for obtaining temperature information of the print head during each scanning operation and for obtaining maximum temperature information of the print head at the previous scanning operation; driving means for driving the print elements by using a pulse signal comprising a preheat pulse and a main heat pulse; selection means for selecting a voltage value of the pulse signal for the next scanning operation based on both of the maximum temperature information obtained by the obtaining means and threshold information corresponding to the voltage value at the previous scanning operation and for selecting a pulse width corresponding to the voltage value for the next scanning operation; and control means for starting to drive the print elements based on the voltage value and the pulse width selected by the selection means for the scanning operation of the print head, and for changing the pulse width during the scanning operation, based on the temperature information obtained by the obtaining means during the scanning operation.