| 摘要 |
A package is conveyed to a package elevator which elevates it into a film sheet stretched above the elevator. Side folding levers and a coordinated rear folder fold three sides of the film sheet about the package such that edges of first and second opposed sides of the film sheet are overlapped by edges of a third or rear side of the film sheet. The infolding of the third side of the film sheet by the side underfolders is delayed at the rear edge of the package by expanding the opening between the side underfolders in that area. Thus, the rear underfolding of the third side commences substantially at the rear corners of the package to expand the underfolded third side and ensure film overlap. The package is then pushed onto a conveyor to underfold the fourth side of the film and entirely cover the underside of the package by overlapping edges of the folded sides of the film sheet. The infolding is delayed by an improved side folding lever having a curvilinear folding edge with a notch formed at its inner end in substantial alignment with the rear edge of the largest packages to be wrapped using the folding lever. Preferably, the notches comprise curvilinear trailing edges which serve to tuck and roll the edges or infolded portions of the third or rear side of the film sheet as it is rear underfolded.
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