| 摘要 |
1323749 Electric heating strips HERAEUSWITTMANN GmbH 16 Sept 1970 [16 Sept 1969] 44326/70 Heading H5H A flexible heating strip with earthing protection includes a plurality of spaced heating conductors 4 with insulation 3, and an earthed conductor 2 in the form of a meshed, laced, woven or knitted metal wire structure surrounds each insulated heating conductor. An outer envelope 1 of a temperature- and chemicallyresistant, synthetic material and/or a covering of glass or asbestos fibres is provided. The conductor 2 may be intermeshed with the insulated conductors, Fig. 3, by weaving, knitting or otherwise interlacing, before the outer envelope is added. Electrical contact with the conductor structure 2 is improved by a bare wire 5 included in the strip. Conductor 2 is of nickel or high grade steel. A thermally insulating layer may be provided on one side of the strip by bundles of glass fibres forming tufts 6, Fig. 5 (not shown), connected with the conductor structure 2. Applications of the heating strip to heating laboratory flasks, metal containers or tubes, furnishings, wall hangings, carpets, hot plates, dinner wagons, or other apparatus for keeping food hot, are mentioned. The strips form heating jackets or heating coverings for machines. Conductors 4 are coils enclosed by an insulating sleeve 3 or a meshed, laced, knitted or woven covering of glass or asbestos fibres. Synthetic envelope 1 is silicone or P.T.F.E. |
