| 摘要 |
An apparatus for pulling a tubular film down over a large object has at least two guide and roller assemblies each flanking the object and each movable vertically along the object. Each assembly has a guide, an outer roller and an inner roller. The film is gathered by positioning the assemblies in an upper position, orienting the inner rollers generally below the outer rollers, and rotating the rollers while gripping the hood between them to pull the tube down and form it into folds beneath the roller assemblies. The film is pulled down over the object by orienting the inner rollers generally above the outer rollers, and then shifting the roller assemblies downward while rotating the rollers so as to pull the tube up and unfold it.
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