| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a printing machine having a protective cover, within which a plate exchanging device is built. <P>SOLUTION: The protective cover 8 consisting of an upper part (a plate exchanging device) 13, a middle part 14 and a lower part 15 normally closes in order to prevent from approaching to rotating rollers for printing. In order to open and close the protective cover 8, a direct drive multi-step driving means 27 and an elastically deforming mechanisms 28 and 29 are employed. Concretely, multiple step cylinders may be employed for the direct drive multi-step driving means 27. When the direct drive multi-step driving means 27 is employed, the vertically opening and closing speeds of the protective cover 8 become different from each other. For example, in the first stage of the closing of the protective cover 8, the protective cover 8 closes at a normal speed and can also be set at a reduced speed on and after the second stage, thus resulting in contriving to coexist the time-shortening and the safety in the vertical opening and closing action of the protective cover 8 with each other. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
