| 摘要 |
An apparatus for feeding a preferably multi-ply web of synthetic thermoplastics comprises a pair of feed rolls, which define a feeding nip and each of which is formed with annular grooves, and two scraping rakes, which are secured in the frame and have tines extending through the annular grooves, wherein at least one of said rakes is movably mounted and arranged to actuate a switch for stopping the drive for the rolls when the scraping rake is moved out of its normal position by the web because it is bulged. It is intended so to improve such an apparatus that the switch will be operated even by relatively small bulges formed in the web. That object is accomplished in that each scraping rake is guided to be movable in the direction of travel of the web. A scraping rake for actuating the switch can be moved by a much weaker force if the rake is displaced in the direction of travel of the web rather than being pivotally moved. The apparatus in accordance with the invention is capable of a much more sensitive response to a bulging of the web than known apparatuses.
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