| 摘要 |
<p>An apparatus for use in a system for making bags or the like from a continuous web or sheet of film material, the system including a perforator for imparting series of transverse perforations onto the web at regularly spaced intervals, which comprises a spreader roll having a reduced diameter portion between two enlarged diameter portions; a switch device located adjacent the reduced diameter portion; wherein the large diameter portions cause each series of perforation to pull apart and form a gap as the web is drawn over the spreader roll; and wherein the switch device is capable of being activated each time a gap passes in close proximity to the switch device.</p> |
