| 摘要 |
PURPOSE:To simplify a structure and improve speed change precision by providing a selecting means selectively moving and engaging only one input gear to one output gear on an input shaft. CONSTITUTION:When individual cams 7 are rotated together with a cam shaft 4 by a driving motor 9, if the recessed cam section 7' of a cam 7b is located at the tip projection 12' of a lever 12, for example, a control lever 8' is rotated clockwise by a spring 14, and an input gear 5b is slid along an input gear 5b and engaged with an output gear 6b on the small-diameter side. The driving force of the input shaft 2 rotated and driven by a driving device is converted at the gear ratio between the input gear 5b and the output gear 6b on the small-diameter side and transferred to an output shaft 3. The rotating speed of the input shaft 2 is constant, but the rotating speed of the output shaft 3 is determined by the gear ratio between input and output gears 5 and 6. An original bed can be fed at the preset feed speed. |
