| 摘要 |
PURPOSE:To improve the quality of folded book by rotating the needle tip of a needle drum in the inner opposite direction from the paper feed direction thereby reducing the tension on the print paper and preventing the bending of the print paper due to the unballance of force of each needle. CONSTITUTION:When a cam roll 14 slides from X to Y positions of a fixed cam 25, the tip of a needle 8 will project through the outercircumferential face of the needle drum 3 and stick into the tip section of a print paper 4 to carry the print paper 4 along the circumferential face of the needle drum 2. In the interval from Y to Z positions, the tip of needle 8 will rotate in the opposite direction from the rotation of the needle drum 2 to reduce tension at the tip of the print paper 4. When sliding from Z position to the end face 25d of a mountain section 25c, the tip of needle 8 will further rotate inwardly while when sliding on the top face 25f, it will departed from the print paper 4 and when returning to X position it will stick again into the tip portion of the print paper 4 to repeat the operation. In such a manner, bending of print paper due to the shift of needle and the unballance of needle force is prevented to improve the quality of folded book. |
