| 摘要 |
<p>1448700 Flexible heating tape PATENTKONSORTIET ROBERT MEINICH & CO 9 Oct 1973 [13 Oct 1972] 46982/73 Heading H5H A flexible heating film comprises a plurality of narrow parallel conductive strips 5 interconnected at opposite ends by a series of short transverse conductive strips 6 to form a meander heating pattern, the strips 6 being formed from transverse strips, e.g. 9 which extend across all all of the longitudinal strips 5 and the strips 5 and 6 being sandwiched between insulating foil layers 2, 3 which are joined together, e.g. by heat sealing, in those areas which are in direct contact. Terminal connector strips 7 are provided at one end of the film. A hot melt adhesive 8 or adhesive tape may protect the two ends of the heating film. In production metal foil 11 is fed to rotating knives 15 to slit it longitudinally. Next, spacers 17 separate the narrow foil strips 5 produced by a gap corresponding to the gap between the longitudinal strips 5 in the finished product. After a lower insulating web 2 has been introduced, transverse connectors 9 are applied across the entire width of the web, an upper insulating web 3 is applied, the webs 2 and 3 are heat sealed together during passage through a welding device 20 and the transverse connectors 9, which comprise copper strips with the underside coated with lead, are soldered to the strips 5 by heated pressure rollers 22. As shown, the strips 9 having staggered notches from opposite side edges is produced from a continuous strip by a pair of punches as it is fed to the moving web 2 and strips 5. When the finished web is cut to length along the centre of the strip 9, the overlapping of the notches from the opposite edges ensures that the separate short connectors 6, joining only two adjacent strips 5 are formed. Alternatively the strips 9 need have no notches, the individual short connectors 6 being formed therefrom by cutting the strips 9 transversely between every second strip 5. Finally the strips 9 may be replaced by correctly sized and spaced short connectors carried on an insulating carrier strip so that no subsequent operation is needed to divide the transverse connector into separate short sections. Wide sections 2 containing no resistive strip 5 are provided along opposite sides of the film to enable the film to be nailed in position. The resistive foil strips 5 are preferably made of lead-tin-antimony alloy and are thinner than the connectors 6 so that the heating effect is determined predominantly by the strips 5.</p> |
