Patent ID: 7448707
Filing Date: 2008-11-11
Classification: B41J

Abstract:
1. A method of expelling ink from nozzles of a printhead module, the method comprising the steps of: (a) providing a fire signal to nozzles at a first and nth position in each set of n adjacent nozzles in each row of a plurality of rows of the printhead module so as to expel ink from the nozzles, the rows being offset from each other in an intended direction of print media movement relative to the printhead; (b) providing a fire signal to the next inward pair of nozzles in each set so as to expel ink from the nozzles; (c) in the event n is an even number, repeating step (b) until all of the nozzles in each set has been fired; and (d) in the event n is an odd number, repeating step (b) until all of the nozzles but a central nozzle in each set have been fired, and then firing the central nozzle, wherein each nozzle is fired simultaneously with the nozzle or nozzles at the same position in at least some of the other rows.