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Band-shaped electrical heating element There are already known electrical heating elements in which non-metallic materials, in particular rubber or rubber-like plastics, are used as the heating conductors, which are rendered conductive by the addition of electrically conductive substances, in particular carbon black or graphite. These heating conductors are provided at two opposite points with supply wires and od in an insulating sheath of rubber. Like. embedded, preferably vulcanized together with this. Such heat elements are particularly suitable for a mild heat generation, which can be dispensed with the otherwise required for heating elements with metallic conductors temperature switch without the heat element reaches excessively high surface temperatures. According to the invention, the production of such electrical heating elements can thereby be substantially simplified and improved, that on both sides of the heating bare metal conductors are inserted, which are over the entire length of the element in conductive connection with the heating element. This makes it possible to produce the heat element in unlimited length, for example by the heating element itself is produced on an extruder; bare metallic wires are inserted on both sides of the heating conductor. The heating element is then provided with a shell made of rubber, the z. B. is applied in Längsbedeckungsverfahren.

Although there are already known heating elements in tape form, which can be produced in unlimited length and in which a corresponding piece can be cut off from the production length as required for textile products as needed. Such band-shaped heating elements consist of a fabric of metallic heating conductors and textile fibers and have been inserted on both sides, z. B. woven, metallic conductor, with which the heat conductor inserted as a shot are alternately in conductive connection. However, such a fabric is not easy to manufacture and has the aforementioned disadvantages of heating elements with metallic heating conductors. The necessary devices for its production are relatively complicated.

Heat elements according to the invention are to be used for a variety of purposes. They are particularly low z. B. suitable for the treatment of diseased limbs. For this they have over known heating elements in the form of sleeves od. Like. The advantage that one and the same thermal element for different cases, for the treatment of strong and weak limbs, z. B. for adults and children, for thighs and wrists are suitable. The band-shaped heating elements according to the invention are wound around the area to be treated several times as needed in narrow or further turns, wherein the heat can be well dosed.

Ribbon-shaped heat elements according to the invention but also for technical purposes, eg. B: to protect piping against freezing, very suitable. Depending on the type and dimensions of the parts to be protected, they can be stretched next to them or wrapped around them in more or less tight turns. In addition, such heat elements according to the invention are also suitable for space heating or as a floor covering in the form of runners or mats, etc.

It is particularly favorable between the laterally inserted metallic. Ladders still embed other bare metallic conductors in the heating element. In this way, heat elements for three-phase connection to three-conductor networks can be formed. But you can also use the individual head to regulate the heat output of the heating element by either parallel or series connection of the individual leads.