Patent ID: 7034855

Claim:
A printing apparatus comprising: a thermal head provided with a plurality of heating elements arranged in a line and divided into a plurality of blocks each of which is energized for printing; a memory that stores data for control of the printing apparatus; and a control unit that performs printing control, wherein the memory includes a printing information storing area that temporarily stores print data including a plurality of printing lines each of which is printed in one printing operation by one line of the heating elements and that has a capacity that is at least double the printing lines to be printed in a time required from a printing stop state to reach a maximum printing constant speed, and the control unit includes a processor for executing: a heating element number counting process for counting the number of heating elements in each printing line by looking ahead, among the print data in the printing information storing area, printing lines at least double the printing lines to be printed in the time required from the printing stop state to reach the maximum printing constant speed; a block number setting process for setting the number of the blocks to be energized in the thermal head based upon a counting result of the heating element number; and a printing speed adjusting process for selecting a printing constant speed from a plurality of printing constant speeds according to the block number set in the block number setting process, thereby adjusting the printing speed for acceleration or deceleration.