Sequential Cutting Motions Patents (Class 83/555)
  • Patent number: 4004481
    Abstract: Device for making a perforation in film material, especially plastics film material, said device comprising a reciprocatable support beam for a plurality of perforating blades the cutting edges of which are saw-tooth shaped. A driving means moves, simultaneously with the support beam a series of suction members in the direction of the operative position and back, said series extending with minor spacing substantially parallel to the perforating blades. Means are provided for the support beam and the series of suction members to perform, during displacement between the operative position and the rest position, but at a distance from the operative position, a relative displacement in the longitudinal direction, such that the top film layer is cut through while the other layer remains just perforated.
    Type: Grant
    Filed: June 24, 1975
    Date of Patent: January 25, 1977
    Assignee: Wavin B.V.
    Inventor: Paul Christian Herman VAN DEN Beld