Patent ID: 7500727
Filing Date: 2009-03-10
Classification: B41J,G06K

Abstract:
1. An ink jet printing apparatus having printing means, wherein the printing means, having a plurality of print heads, each formed with a plurality of nozzles, performs printing onto a print medium while the plurality of print heads are scanned across the print medium, wherein each time a print head performs printing while being scanned across the print medium, the print head conducts printing in a respective predetermined print area defined by an entirety of the area which can receive ink during a respective pass of the printhead across the print medium, the print heads being adapted to eject different kinds of ink onto the print medium to form an image according to print data transferred from a predetermined print data source, among the plurality of print heads, a print head for ejecting a specific kind of ink is formed with nozzles along a nozzle arrangement direction, a nozzle arrangement in the nozzle arrangement direction in the print head for ejecting the specific kind of ink being more than twice as long as a nozzle arrangement in a nozzle arrangement direction in another print head, and a portion of the nozzle arrangement in the print head for ejecting the specific kind of ink corresponding to printing positions different from printing positions printed by nozzles in the other print head being longer than the length of the nozzle arrangement of the other print head, the ink jet printing apparatus comprising: print buffers for storing print data corresponding to each of the print head for ejecting the specific kind of ink and the other print head, a capacity of the print buffer corresponding to the other print head being smaller than a capacity of the print buffer corresponding to the print head for ejecting the specific kind of ink; discrimination means for discriminating a data transfer mode of the print data transferred from the predetermined print data source as to whether the transfer mode is: print head control means for setting a range of the nozzles to be used during the scanning of the printing means, from among the plurality of the nozzles arranged in the print head for ejecting the specific kind of ink, based on the result of the discrimination means, wherein, in the first print data transfer mode, the print head control means sets the range of the nozzles so as to use a nozzle, in a range corresponding to the first predetermined print area, from among the nozzles arranged in the print head for ejecting the specific kind of ink, and wherein, in the second print data transfer mode, the print head control means sets the range of the nozzles so as to use nozzles, in a range corresponding to the second predetermined print area, from among the nozzles arranged in the print head for ejecting the specific kind of ink.