| 摘要 |
1,060,433. Tubular films. REIFENH€USER G.m.b.H. Feb. 7, 1964 [Feb. 11, 1963], No. 5319/64. Heading B5B. Apparatus for cooling continuous extruded air-inflated tubular films of thermoplastic resinous material comprises a liquid-cooled calibrating and supporting tube member attached to the extrusion nozzle and cooling the film passing therethrough by direct contact and, connected to the liquid-cooled member, an aircooled calibrating and supporting tube member, spaced apart from the film so that an annular air current passes between the film and the inner wall of the air-cooled member. A housing consisting of a plurality of intercommunicating concentric cylinders surrounding the film may be located between the liquid-cooled and aircooled tube members. In one embodiment (Fig. 1, not shown), a tubular film extruded from annular nozzle 1 is inflated and expanded to contact a calibrating tube 3 which is connected to nozzle 1 and which is cooled by liquid flowing in ducts 4. The film then passes through an air-cooled calibrating member comprising a cylinder 16, spaced apart from the film so that an air-cushion exists in space 9 between the film and cylinder 16. The aircooled member 16 is connected to the liquidcooled member 3 by a labyrinthine housing comprising interconnected cylinders 17-20, to which air is supplied by three inlets 11. Inner cylinder 20 may lie against the film. In a further embodiment, additional cooling is provided by an annular trough, attached to the top of the air-cooled member, having radially arranged nozzles spraying liquid on to the film. The calibrating and supporting tube members may be of any cross-section and may taper in the direction of extrusion to compensate for the contraction of the cooling film. |
