| 摘要 |
<p>Device for winding a wrapping film around an article (1) to be packaged, said article to be packaged having the shape of a substantially flat rectangle in cross-section. The article to be packaged comprises two substantially parallel broad sides (2, 3) and two narrow sides (4,5), the edges between the broad and narrow sides forming supporting points (6) for the wrapping film. The device comprises a film distributor (7) disposed to travel along a ring-like endless track (8) at a substantially constant speed around the article to be packaged. The track (8) of the film distributor (7) is so formed that the track radius (r) from the track to the supporting point (6) increases continuously at least in the track area (S) where the film portion (12) drawn from the roll in the direction of the radius and stretched between the film distributor and the supporting point (6) approaches a position parallel to at least one broad side (2; 3) of the article being packaged, said position corresponding to a point (0) where a straight line in the direction of said broad side intersects the track (8), so that, when said point (0) is being approached and at said point, a tangent (T) to the track is at a smaller angle to the straight line in the direction of the broad side than a tangent to an imaginary circular path, the rate of increase of the radius (r) at least in said area of the track and the rate of delivery of film from the film roll (9) being higher than if the track followed the imaginary circular path mentioned. At and after said point (0) on the track, the rate of increase of the radius (r) remains substantially the same as before point (0), with no substantial changes occurring in the rate of increase of the radius. <IMAGE></p> |
