Patent ID: 7300219
Filing Date: 2007-11-27
Classification: B41J

Abstract:
1. A thermal type image forming apparatus comprising: a platen roller; a thermal printing head (TPH) unit facing the platen roller and pivoting to contact or separate from the platen roller; a first elastic member which elastically biases the TPH unit toward the platen roller; a pair of cam levers provided on both sides of the TPH unit; and a pair of rotation cams which contact the pair of cam levers and allows the TPH unit to pivot according to a rotation angle thereof, wherein the TPH unit rotates around the platen roller to be disposed in first and second positions where the TPH unit faces the first and second surfaces of a printing medium, and to initiate a phase of the pair of rotation cams, at least one of the pair of the rotation cams includes a stopper which is caught by the cam lever at a position where the TPH unit is separated from the platen roller by a maximum gap.