DK144839B - MULTI-CORN FLEXIBLE ELECTRIC WIRE - Google Patents

Description

in 144839

The invention relates to multi-core flexible electrical wires known as "plastic hose lines" or "rubber hose lines". Such wires are used in particular for power supply of mobile devices, e.g. also for power supply of 5 household appliances such as vacuum cleaners, coffee makers and drilling machines.

A special type of wiring has been developed for domestic heating utensils, ie. for tools where a heated part of the apparatus may come into contact with the cord, such as e.g. is the case with 10 toasters and irons. Such wires usually consist of several knotted rubber insulated cores, which are surrounded by a braid network of textile and / or plastic fibers. The winding spaces between the joined choirs are usually filled with winding fills, e.g. with cotton stride (German usage pattern 72 38 145). In an improved embodiment 15, it is proposed to use a rubber sheath as an outer sheath on which is placed a casing of mercerized cotton. With such cables, it is considered an advantage that the casing of mercerized cotton has a low coefficient of friction, so that the cord e.g. glides easily on the fabrics ("Der Elektromeister + Deutsches Elektrohandwerk", 20 booklet 19, 1975, page 1213).

In addition, it is known for rubber hose lines to be used at elevated temperatures, to use ethylene vinyl acetate or silicone rubber material for both insulation and casing.

25 Also known are single-core wires on whose rubber insulation is applied a lacquer layer of a condensation-curing lacquer for protection against chemical stresses, in particular to improve the resistance to ozone and fuel. Such wires are used as ignition cables in cars and airplanes (German patent 935 253).

The use of a lacquer coating is also known by multicore flexible electrical wiring. Here, a sliding lacquer is applied to the individual choirs to improve the internal friction conditions and thus the flexibility of the conduit (German publication publication 25 28 307).

For the manufacture of lacquer-insulated electrical wires, which the 35 are processed into coils, modified alkyd resin-based paints, which are distinguished by heat and temperature resistance, are also known (German Patents 953 182 and 1 125 023).

2 144839

The invention relates to multi-core flexible electrical wiring for power supply of mobile domestic heating appliances such as e.g. irons and toasters to replace it heretofore by a rubber sheath and a slip-resistant outer protective layer in the form of a 5-yarn braid mesh sheath with a mechanically approximately equivalent sheath, which improves the thermal and electrical safety of the conduit as much as possible, and which has more favorable manufacturing costs.

According to the invention, this task is solved by the fact that the rubber jacket 10 consists of a cross-linked ethylene-vinyl acetate copolymer or a cross-linked chlorosulfonated polyethylene, and that the slip-resistant protective layer consists of a thin coating of an alkyd resin-based heat-resistant lacquer.

An electrical cord with a casing thus constructed is highly resistant to the heat effects occurring during use of the cord and is sufficiently flexible and is characterized by an equally good coefficient of friction as the textile yarn braided wires. Furthermore, the casing structure ensures that the ends of the cord can be provided with plugs known per se, if e.g. of polyvinyl chloride 20 housing is applied by injection molding.

An exemplary embodiment of the present wire is shown in the drawing.

The conduit 1 consists of three interconnected cores 2, each consisting of a fine-wire copper conductor 3 and an insulation 4 of a cross-linked ethylene-propylene rubber yoke. A sheath 5 of an extruded and cross-linked ethylene-vinyl acetate copolymer is applied to the three interconnected cores. In addition, the heat-resistant lacquer layer 6 is of an alkyd resin-based lacquer which is applied in direct connection to the cross-linking of the sheath 5 by pulling the conduit through a lacquer solution.

Such a wire was used as a connection wire for an iron. This gave excellent slip properties on the treated fabrics. Furthermore, after an application of the approx. 240 ° C heat sole of the iron for a period of approx. 30 minutes on the 35 wiring surface, no damage to the plastic casing which degraded the conductivity of the wire was found. The utility value of such a cord is thus significantly higher than the utility value of the conventional wires so far used for such a purpose, with a wrap of textile yarn.