| 摘要 |
A feed mechanism is provided for a roll of sheet material, said material being shrink film for capping and closing the open end of a container. The feed of the film is directed downward from the roll and faked as it is unrolled around a tension rod freely mounted in vertical elongated openings formed in spaced brackets and holding the film suitably taut by the weight of the rod. Also, during pay-out of the film from around the freely mounted rod, a timer cam is rotated at the top of the machine to activate a pair of spaced clamps with gripping fingers to a clamping position of the free end of each corner of the film and to pull the film sheet a predetermined distance to cover the open top of a container to be capped and sealed. The clamps are normally spring closed, until one-way cam means momentarily open the same just prior to the clamping action on the film to receive edge portions of the film and then released to close over said film to pull the film sheet for the said predetermined pull distance. A linkage is timed by the timer drive cam and is operated to transversely cut the sheet into a portion with a sufficient marginal portion to overhang the open mouth of the container. The container is mounted on an elevator means to be elevated into a heat sealing area, so the marginal area is sealed by heat over the top of the container, whereupon when the elevator is lowered the capped container may be removed and the film feeding and capping repeated.
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