JPS6134708Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a surface heating element used in electric carpets, electric heating boards, etc.

Conventional surface heating elements are made by depositing a metal foil on one side of an insulating film, etching the metal foil to create a zigzag-shaped metal foil heater wire, and placing an insulator on top of the metal foil heater wire. It is manufactured by gluing films together.

Electric carpets, electric heating boards, etc. using such surface heating elements are inconvenient to store because of their planar shape, and there is a strong desire to fold them when stored. However, conventional surface heating elements tend to suffer from elastic fatigue when bending stress (strain) is applied to them, and the metal foil heater wire breaks after being bent several times, resulting in extremely shortened service life. There was a problem.

Therefore, the object of this invention is to provide a surface heating element that can extend its life when used in folded condition.

An embodiment of this invention is shown in FIGS. 1 and 2. That is, this surface heating element is a bendable surface heating element constructed by sandwiching a zigzag metal foil heater wire 1 between two insulating films 2 and 3. A plurality of parts 1 are provided in parallel so as to intersect at right angles to the folding line A,
In addition, they are approximately evenly distributed in the length direction of the folding line A.

In this way, in this embodiment, a plurality of metal foil heater wires 1 located on the folding line A are provided in parallel so as to intersect at right angles to the folding line A, and
Since the distribution is almost even in the length direction, the bending force is applied almost evenly in the length direction of the folding line A of the surface heating element, and elastic fatigue is dispersed, and the metal foil heater at the bending part is Breakage of each wire 1 is less likely to occur than in the conventional example, resulting in a longer service life.Moreover, even if one or more wires break, current can be ensured with the remaining wires. Since cracks in the heater wires are not transmitted to the rest of the heater wires, there is no chain of disconnections, and a sufficiently long life can be achieved. Furthermore, since the metal foil heater wire 1 is formed by etching or the like,
Even if multiple units are installed in parallel, the cost will not increase.

As described above, the surface heating element of this invention is a bendable surface heating element that is constructed by sandwiching a metal foil heater wire between two insulating films, and the metal foil heater wire portion of the folding line is set at right angles to the folding line. The surface heating element is characterized in that a plurality of them are arranged in parallel so as to intersect with each other, and are distributed almost evenly in the length direction of the folded line, so that the bending force is applied almost equally in the length direction of the folded line of the surface heating element. As a result, elastic fatigue is dispersed, and each metal foil heater wire is less likely to break at the bent part than in the conventional case, resulting in a longer service life.Moreover, even if one or more wires break, Electricity can be ensured with the remaining wires, and since a crack in one metal foil heater wire is not transmitted to the remaining wires, there is no chain reaction and disconnection, and a sufficiently long life can be achieved. There is an effect that it can be done.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of this invention, and FIG. 2 is a sectional view thereof. 1... Metal foil heater wire, 2, 3... Insulating film, A... Folded line.

Claims (1)

[Scope of utility model registration request] In a bendable surface heating element configured by sandwiching a metal foil heater wire between two insulating films, a plurality of metal foil heater wires are provided in parallel so that the portion of the metal foil heater wire on the folding line intersects at right angles to the folding line, and A surface heating element characterized by being distributed almost evenly in the length direction of the folded line.