Patent ID: 7891893

Claim:
A printing apparatus comprising: a thermal recording paper conveyance mechanism which conveys thermal recording paper along a paper conveyance path; a first thermal head which is provided along the paper conveyance path, and is arranged to face a first surface side of the paper conveyance path; a first platen roller which is arranged to face the first thermal head across the paper conveyance path; a first spring that biases the first thermal head toward the first platen roller; a second thermal head which is provided along the paper conveyance path and on a supply side of the thermal recording paper with respect to the first thermal head, and is arranged to face a second surface side of the paper conveyance path; a second platen roller which is arranged to face the second thermal head across the paper conveyance path; a second spring that biases the second thermal head toward the second platen roller; a drive mechanism that includes a selective torque transmission mechanism that drives only the first platen roller in a conveyance direction of the thermal recording paper, and drives both the first platen roller and second platen roller in a reverse conveyance direction, wherein the second platen roller is driven only by the thermal recording paper in the conveyance direction, and the circumferential velocity of the second platen roller is set to be greater than that of the first platen roller in the reverse conveyance direction.