| 摘要 |
<p>PURPOSE:To enable a film to be conveyed matching with its perforation speed while ensuring its plane quality by a machine simplified in its structure by correlating a sprocket and a feed roller to each other in a manner wherein a linear speed of the sprocket is a little higher than the linear speed of the feed roller. CONSTITUTION:A punching part 5 provides in its downstream side a sprocket 6 meshed with perforation after punching further in the upstream side a pad roller 3' and a feed roller 3 holding a film 2. This sprocket 6 is correlated with the feed roller 3 through timing pulleys 21, 23 and a timing belt 22. Here the sprocket 6 sets its linear speed a little higher than that of the feed roller 3, slipping the film 2 held by the feed roller 3 and the pad roller 3'. By this slipping of the film 2, it is given back tension, and the film 2, while its plane quality is ensured, is conveyed at a high speed matching with a perforation speed of the film.</p> |
