Patent ID: 8011844

Claim:
A printer, comprising: a main body having a paper roll container for containing a paper roll in which belt-shaped paper is wound plenty of times; a lid rotatably attached to the main body for closing an opening section of the main body through which opening section the paper roll is loaded in the paper roll container; a letter printing mechanism which operates when the lid is closed and prints a letter (image) on the belt-shaped paper of the paper roll by pulling out the belt-shaped paper from the paper roll container; and a detecting arm which detects a near-end state of the paper roll contained in the paper roll container; wherein the detecting arm is rotatably attached onto a rear surface of the lid, when the lid is closed, the lid is disposed at an approximately vertical position, an upper part of the detecting arm is held by the rear surface of the lid as a rotational center, the detecting arm is rotated so that the detecting arm protrudes into the paper roll container, the rotation of the detecting arm is stopped when the detecting arm contacts an outer circumferential surface of the paper roll contained in the paper roll container, and when the paper roll reaches the near-end state, the detecting arm is not stopped by the outer circumferential surface of the paper roll and rotates by a predetermined angle.