| 摘要 |
1,147,466. Cutting and welding plastics tubing to form bags; seaming non-metallic sheet material ; cutting webs. KUREHA KAGAKU K.K. 17 May, 1966 [17 May, 1965; 1Dec., 1965; 2 Dec., 1965], No. 21941/66. Headings B4B, B5D and B5K. Flattened tubular film is transversely cut into bag lengths by a rotary blade 38 in an area held between welding jaws 32, 40 and a clamp 31, 37: the jaws then weld the film and an air blast cools it. High frequency current to the welding jaws rnay be applied before the cutting, but is not sufficient to effect welding before the cut is complete. The rotary knife is moved axially into and from its cutting position: in the embodiment illustrated its cuts at each fourth revolution. The web is fed from a roll 5, mounted on an arm 7 so that it rests by gravity on a driven roller 8, and then passes through pinch rolls 9, 9a, driven intermittently through a ratchet (13) (Fig. 7a, not shown) from an adjustable crank (15). The feed may be controlled by a clutch operated by a photo-cell detecting markings on the tubing. The completed bags are fed by pinch rollers 41, 42 to conveyers (57), (58) (Fig. 7a). |
