| 摘要 |
Opening arrangements for packing containers are realized inter alia in the form of a portion of the wall of the packing container delimited by means of an opening indication line which portion is opened with the help of a tearing thread. The application of the tearing thread along a nonrectilinear opening indication line is difficult and up to now it has not been possible to realize it automatically in the rapid manufacture of packing containers from e.g. a moving material web. In accordance with the invention an opening arrangement is now provided wherein an openable part (6) of the container wall, limited by a curved opening indication line (5 min ), is opened with the help of a tearing thread (7) which extends rectilinearly between two points on the opening indication line (5 min ). The tearing thread (7) is applied so that on opening it follows and breaks up the material of the packing container along the curved opening indication line (5 min ). The possibility of applying the thread rectilinearly makes the opening arrangement especially suitable for application in the manufacture of packing containers from a moving material web, since the thread can be applied at high speed parallel with the direction of the web. |
