US2973425A - Electrically warmed mats or matting - Google Patents

Description

Feb. 28, 1961 A. KELEMEN 2,973,425

ELECTRICALLY WARMED MATS OR MATTING Filed May 20, ,1959

Ufl tsd S e P m ELECTRICALLY WARMED MATS on MATI'ING Leslie Andrew Kelemen, 19 Carlotta Road, Double Bay, near Sydney, New South Wales, Australia Filed May 20, 1959, Ser. No. 814,442 Claims priority, application Australia May 21, 1958 5 Claims. (Cl. 219-46) This invention has reference in general to mats and matting incorporating an electrical conductor which by radiation, applies heat throughout the whole or practically the whole of their exposed surfaces.

In using the known forms of warmed mats or matting, it has been found that those articles tend to crease, with the result that, after the passage oftime the electrical conductor or conductors incorporated therein tend to fracture, and this interrupts the flow of electricity or impairs the heating efiect normally imparted by it.

The present invention has been devised in an attempt to prevent creasing of the mats or matting, at least in one direction, and it thus renders those articles more efficient as warming devices especially for incorporation in, or application to the upper surface of bed mattresses.

According to the present invention the mats or matting are made up of a plurality of threads which, in general, are woven much as ordinarily. However, those threads which constitute the weft are arranged in clusters alternately with one or more single strands; and the electrical conductor, which consists of a fairly fine flexible copper strand or strands is enclosed, as a single thread or as a helix around a flexible core, in each of the beforementioned clusters.

Preferably the weft is of jute or other relatively inexpensive textile material, and it is intertwined by the warp threads as in normal weaving. When higher temperatures are to be provided for, the weft may be of fibre glass or similar materials.

The warp threads of the mats or matting can be relatively thin, and preferably they are of cotton or like strong material; though the warp threads too, may be of fibre glass or similar materials when higher temperatures are to be provided for. The complete mats or matting are characterised in that the clusters of the weft threads create ribs at intervals throughout the material. Those ribs carry within them the flexible electrical conductor, and thereby serve to insulate and protect it. They also serve to minimize the possibility of the mats or matting being creased longitudinally as distinct from transversely. That is to say, in its application to a bed mattress the woven material is permitted to crease transversely of the mattress; but provided it is kept reasonably flat as by tapes around its margin it will not crease longitudinally of the mattress.

While the present invention has been devised primarily to provide improved Warming mats for the upper surface of a bed mattress, if desired, they can be used to warm the upholstery of lounge chairs, and the like. They can also be used under or incorporated in carpets or carpeting to impart a uniform heating effect to enclosed apartments, the electrical conductor in the mats or matting being connected to a suitable source of electric energy, if necessary through the medium of a step-down transformer or other appropriate electrical device of known type.

A further feature of the present invention resides in the fact that the electrical conductor is formed helically and,

, 2,973,425 Patented Feb. 28, 1961 preferably, is wound around a j'ute thread which constitutes a core for the conductor.

In order however, that the invention may be clearly understood and readily carried into practical effect, reference is now made to the accompanying drawings wherein:

Figure 1 represents the plan of portion of an electric mat constructed in accordance with one practical application of the present invention and suitable for attachment to or incorporation in the upper portion of a bed mattress.

Figure 2 is a section taken on the plane 2-2 of Figure 1.

Figure 3 is a magnified sectional fragment, in perspective, of the mat represented by Figure 1.

Figure 4 is a view similar to Figure 1, but representing a mat wherein there are eight weft strands between each cluster.

Figure 5 is a section taken on the plane 55 of Figure 4.

Reverting to Figure 1 it will be seen that the mat thereby represented is made up of a plurality of weft threads 10 and a plurality of warp threads 11 interwoven by known weaving means. However some of the weft threads 10 are arranged in clusters 12 as indicated in Figure 2: that is to say, in this particular form the mat, starting at the top edge, has two single weft threads 10 side by side. There is then a cluster 12 of four weft threads 10 and then two more single weft threads 10 and so on, alternately.

The beforementioned electrical conductor 13 is woven into the mat as a weft thread and passes from side to side of the mat within each cluster 12.

In a practical application of the invention, adopted by way of experiment, the electrical conductor 13 consisted of eight twisted strands of .0052 wire wound helically around a jute core, such as 14 (see Figure 3). That arrangement proved quite satisfactory.

The exemplification of the invention illustrated by Figures 4 and 5 is much the same as that shown by Figures 1 and 2, but in that second exemplification the mat has eight single weft threads 10 between each cluster 12, instead of two.

The improved mats or matting can be heated by either AC. or DC. current supplied by normal electrical installations, through the medium of voltage break-down appliances of known type, care being taken to ensure that the current cannot rise to a dangerous degree.

When intended for the warming of bed mattresses, the improved mats would be furnished with suitable tapes, or other known fastening means such as press-studs, so they may be secured to the upper surface of the mattress. Alternatively, the mats could be incorporated in the mattress itself. 1

It will be appreciated that apart from their domestic uses, the mats or matting may be employed for drying-out and other known purposes in industrial establishments.

I claim:

1. An electric warming mat of Woven construction comprising a plurality of weft threads arranged in clusters at intervals throughout the length of said mat and spaced by at least one weft thread, the weft threads of each cluster together being sufficiently stout to prevent formation of creases across them, and a flexible electrical conductor longitudinally enclosed within said clusters and woven into said mat, said conductor electrically insulated by the several weft threads constituting said clusters.

2. An electric warming mat of woven construction as defined in claim 1, wherein said flexible electric conductor consists of a plurality of wire strands wound helically around a weft textile thread constituting a core.

3. An electric warming mat of woven construction as defined in claim 1, wherein each of said clusters comprises at least four threads grouped together in parallel relation to each other and surrounding said electrical conductor throughout their length.

4. An electric warming mat of woven construction as defined in claim 1 wherein said clusters create evenly spaced parallel ribs throughout the length of said mat.

5. An electric warming mat designed to be attached to the upper surface of a bed mattress, said mat comprising a plurality of weft threads arranged in clusters at intervals throughout the length of the mat, said clusters spaced from each other by at least one weft thread, the weft threads of each cluster together being sufficiently stout to prevent formation of creases across them, a flexible electrical conductor woven into said mat and longitudinally enclosed within said clusters and electrically inuslated by the weft threads constituting said clusters, and means on said mat for fastening said mat to the upper surface of the mattress.

References Cited in the file of this patent UNITED STATES PATENTS 729,171 Herrgott May 26, 1903 1,368,412 Rohne Feb. 15, 1921 1,615,294 Turver Jan. 25, 1927 2,490,417 Cochran Dec. 6, 1949 2,610,286 Cox Sept. 9, 1952

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