| 摘要 |
Apparatus for severing bags from a two-ply web of thermoplastic material. The apparatus includes web guide rollers defining a nip, and a plurality of peripheral grooves in the guide rollers in which upper and lower air directing tubes are positioned to guide a web as it passes downstream of the feed rollers. A continuously transversely moving severing knife is provided downstream of the feed rollers and below the plane defined by the moving web. A pair of welding jaws are provided adjacent the cutting knife to grip the web in a plane below the web movement plane to weld the plies of the web together and to deflect the web into position for providing a transverse cut therein by means of the severing knife. A pivot lever is provided to pivot downstream ends of the lower air directing tubes in a downward direction to prevent interference between the downwardly deflected web and the downstream ends of the air directing tubes. A set of clamping jaws is provided on the opposite side of the severing knife from the welding jaws in order to securely hold the web during the cutting operation. |
