| 摘要 |
Device comprises at least one perforation welding tool (5) and a supporting frame (6) having guiding rollers (7) on one side of a sheet of plastic film (1) and an actual value sensor in the form of an air blast tube (9) connected to a pressurized air source and having at least one air outlet opening (12) at least on the side facing the sheet of plastic film. The air blast tube interacts with a measurement reader (14) which is connected to a drive of the preferential roller pair (2) and/or preferably the take-up roller pair (3). The air blast tube has on its side having the air outlet opening and facing the sheet of plastic film a wall surface (11) which is essentially parallel to the sheet of plastic film. |
