| 摘要 |
PURPOSE:To increase a shear force of a fixed ink layer, facilitate releasing of a printing ribbon from a printing paper and reduce vibration and releasing noise of the ribbon, by enlarging the releasing angle of the ribbon against the paper. CONSTITUTION:The printing ribbon 3 from which an ink is transferred onto the printing paper 2 by a printing head 1 is wound around a guide piece 13 by a force generated by a take-up core 12 and the head 1. An end part around which the ribbon 3 is wound is so shaped that the angle formed between the paper 2 and the ribbon 3 released is not larger than 90 deg., and the tip of the end part has such a radius of curvature that the ribbon 3 is not cut by a taking- up tension. An abrupt bending stress is generated in an ink layer on the ribbon 3, and a crack is generated at the boundary between a part fixed to the paper 2 due to printing and a non-fixed part, so that the ribbon 3 can be smoothly released. |
