METHOD OF SLOTTING OPENINGS IN PLASTIC BLANK AND A DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2018 - IPC B29D19/04 

FIELD: technological processes.

SUBSTANCE: invention relates to devices for slotting openings in thermoplastic films along the contour of openings and can be used in various branches of the national economy in the manufacture of shelters for greenhouses, bags, covers, etc. Method for cutting the opening in the plastic blank includes feeding the plastic blank, pressing the blank against the heated annular knife, removing the blanking out from the plastic blank with the ejector. Annular knife has a surface in the form of a cylinder and an inclined (cone-shaped in the case of a circular hole) surface. Cutting edge of the annular knife is parallel to the plane of the plastic blank. Cylindrical surface of the annular knife is located on the inner side, and the inclined surface of the annular knife is located on the outside of the annular knife. Part of the material from the opening in the plastic blank during operation is removed through the inner cylindrical part of the annular knife.

EFFECT: technical result of the invention is to increase the durability, reliability and manufacturability of the service.

5 cl, 1 dwg