| 摘要 |
PURPOSE:To perform the unidirectional winding-up of an ink ribbon regardless of the movement direction of a printing head, by providing an one-way clutch for changing over the rotation of a pulley, which is reversibly rotated by the reciprocal movement of a feed belt, to one direction. CONSTITUTION:A coupling 22 is engaged with the wind-up core of a ribbon cassette and a feed belt 7 is driven to wind up an ink ribbon. In the case of printing in a positive direction, the feed operation of the ink ribbon is performed by rotating a pulley 14 to the direction shown by the arrow while rotating a shaft 25 to the same direction as the pulley 14 by a clutch plate 23. At the time of positive rotation, an one-way clutch 17a is rotated and, when at the time of reverse rotation, an one-way clutch 18a is rotated and the coupling 22 is rotated to an ink ribbon wind-up direction through a gear train regardless of the movement of a carrier, that is, the rotary direction of the pulley 14. |
