| 摘要 |
PURPOSE:To enable each split roller to be independently rotated and prevent a frictional force from being generated at the part of direct contact of a thermal head with a printing roller, by splitting the printing roller for pressing a thermal recording paper against the thermal head into a plurality of split rollers, and fixing each of the split rollers to a driving shaft. CONSTITUTION:Let the frictional force between each half-friction split roller and a shaft 4 be F3 and the frictional force between a thermal head 2 and each of the split rollers be F4, then a setting condition of F4>>F3 ensures that each of the split rollers 8, 9, 13, 14 makes direct contact with the thermal head, and is not rotated. Of the split rollers 8-14 into which a printing roller 3 is split, those making direct contact with the thermal head 2 are not rotated, so that no frictional force is generated at the parts of direct contact of the head 2 with the roller 3. Therefore, the head and the printing roller are prevented from being damaged, and a rotating torque of a controller is prevented from being varied according to the width of a thermal recording paper. |
