Thermal printer.

摘要

A forward/backward printing thermal printer which brings a printing paper onto a printing member and performs a printing action in order to form an image. The printer comprises a thermal head which transfers the image onto the paper according to an image signal, a platen roller which moves the paper back and forth when it rotates, and a pair of paper pressing means which press the paper on the platen roller and cause it to move back and forth with the roller. When the paper moves and is no longer held on one side by a paper pressing means, the paper pressing means on the side where the paper has been released is moved on the outer circumference of the platen roller by a fan-shaped gear rotated by a drive gear so as to again grip the edge of the paper which is carried to the position of the other paper pressing means. In this way, the effective printing range on the paper is enlarged without any error in the paper's position or color due to the transport mechanism. The printer can also be made compact.