| 摘要 |
PURPOSE:To prevent an ink ribbon from sagging and prevent the ribbon from jamming, by providing feeding rollers at a left and a right position, and feeding the ink ribbon in the same directions as the moving directions of a printing hammer by using motors as drive sources. CONSTITUTION:Feeding rollers 2, 3 are disposed in a ribbon cassette 1, and are coupled directly to motors 4, 5, respectively. The feeding roller 2 takes in an ink ribbon 6 when being rotated clockwise, whereas the feeding roller 3 takes in the ribbon 6 when being rotated counterclockwise. The ribbon 6 are pressed by leaf springs 7, 8, whereby it is so tensioned that it does not sag on the front side of a printing hammer 9. The ribbon 6 are pressed by leaf springs 7, 8, whereby it is so tensioned that it does not sag on the front side of a printing hammer 9. The ribbon 6 is twisted 180 deg. at a Mobius twisting part 10, and an upper part and a lower part of the ribbon 6 are used for printing while the ribbon 6 makes a round. When the rotating frequency of the motor 4 is set to be higher than that of the motor 5, the ribbon 6 is advanced by an amount corresponding to the difference between the rotating frequencies of the motors during one reciprocation of the ribbon 6, so that the repeated use of the same ribbon parts for printing can be obviated.
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