| 摘要 |
The invention is in the technical field of packaging and relates to a method and apparatus for perforating webs and sheets of varied construction on a variety of web processing equipment. The perforations are accomplished on an advancing web by means of an apparatus which incorporates a rotating cylinder with multiple pins.Stationary knives interact with rotating pins on the pin-cylinder,thereby perforating holes. Perforated holes in the web or sheet thus made,have a distinct and unique configuration. A great variety of perforating patterns can be obtained by either changing pin location on the pin-cylinder, by disengaging knives on the knife-support, or by varying the rotational speed of the pin-cylinder while keeping web-speed unchanged. The perforating action of all pins on the pin-cylinder can be interrupted for any length of time by lowering the knives which are normally in a fixed position and consequently restoring the original position of the knives to continue the process of perforation. Individual cutouts,thumb-notches and various designs can be perforated in webs and sheets by special pin location and by adapting a four-way operable carriage to the perforating apparatus.
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