Patent ID: 7207644
Filing Date: 2007-04-24
Classification: B41J

Abstract:
1. A printing apparatus for performing printing on a printing medium by reciprocally scanning a carriage to which a printhead having a plurality of printing elements is mounted, said printing being performed during acceleration, deceleration, and constant-speed movement of the carriage, said apparatus comprising: a buffer storing print data to be used in a printing operation for one scan; counting means for counting at least a part of the print data, stored in said buffer, which causes the printhead to perform a printing operation during acceleration of the carriage; comparison means for comparing a counted value, counted by said counting means, with a predetermined threshold value; control means for controlling to change a number of printing elements of the printhead to be used in a printing operation for one scan of the carriage, based on a comparison result of said comparison means; a DC motor for driving the carriage; a power source for supplying electric power to the printing apparatus; and determination means for determining whether or not the power source is an AC power source or a battery power source, wherein the number of printing elements of the printhead to be used in a printing operation for one scan of the carriage, which is controlled by said control means, satisfies a condition such that a sum of a driving current required for driving the number of printing elements and a driving current supplied to the DC motor for accelerating the carriage is equal to or lower than a capacity of the power source, and wherein, in a case in which it is determined by said determination means that the power source is a battery power source, controlling is performed by said control means, and in a case in which it is determined by said determination means that the power source is an AC power source, the counting by said counting means, the comparing by said comparison means, and the controlling by said control means are skipped.