JPH07254479A - Flat heater and manufacture of heating unit thereof - Google Patents

Abstract

PURPOSE:To facilitate handling of a heater element, and prevent short circuit between the elements by cutting reinforcing bridge parts after it is bonded and fixed by a thin holding insulating sheet before cutting from the reinforcing bridge parts. CONSTITUTION:A metallic foil body 4 in which a heater element 2 patterned in a prescribed shape and reinforcing bridge parts 3 are formed is manufactured on a metallic foil base material 1. A heat resistant film or a thin holding insulating sheet such as a laminated mica prepreg sheet or varnish impregnated glass cloth is set on both surfaces or a single surface in a part of the base material 1 containing the foil body 4, the element 2 and the bridge parts 3, and both are bonded together by heating, pressurization or heat resistant resin. The unnecessary bridge parts 3 and the base material 1 are removed by a press or the like, and a heating unit 6 is manufactured. Afterwards, cover insulating plates 7 are fixed to both surfaces of the unit 6. By this method, a creeping discharge distance can be secured with high reliability without position deviation of the element 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar heater, and more particularly to a metal foil body comprising a metal foil base material and a heater element patterned in a predetermined shape and a plurality of reinforcing bridge portions. Then, a thin holding insulating sheet is fixed to one or both sides of the metal foil body, and then unnecessary reinforcing bridge portions are cut off and removed to produce a heating unit. The present invention relates to a planar heater that is used.

[0002]

2. Description of the Related Art Conventionally, a sheet heater having a metal foil as a heating resistor has a metal foil body formed by punching or etching, that is, a metal foil base material 1 shown in FIG. The heater element 2 is separated from the metal foil body 4 formed with the heater element 2 and a plurality of reinforcing bridge portions 3 by hand or by pressing and set on an insulating plate such as a ceramic plate or a mica plate. It was fixed with an adhesive or with a prepreg sheet by heating and pressurizing to create a heating unit. A cover insulating plate is fixed on both sides of the heat generating unit to manufacture a planar heater.

[0003]

According to the conventional method for manufacturing a planar heater, in manufacturing the heat generating unit, the heater element 2 is cut from the reinforcing bridge portion 3 to insulate the ceramic plate, the mica plate or the like. Since the process of setting on a plate or prepreg sheet is adopted, the heater element 2 after cutting is entangled and it is difficult to maintain its original shape,
Once the shape collapses, it is almost impossible to restore it to its original state, and it is difficult to handle the heater element 2 after cutting.

Further, when the heater element 2 is set on an insulating plate or the like, its position is likely to be displaced, and there is a drawback that insulation failure between the elements at the ends is likely to occur. The present invention aims to solve the above drawbacks,
A method of manufacturing a heat generating unit that facilitates handling of the heater element, secures the creepage insulation distance of the heater element with high reliability, and prevents short-circuiting between the elements, and the surface shape using the heat generating unit. The purpose is to provide a heater.

[0005]

In order to achieve the above object, a method of manufacturing a sheet heater and a heating unit thereof according to the present invention is a heater element of a metal foil which is patterned in a predetermined shape on a metal foil base material. And a plurality of reinforcing bridge portions are formed, and a thin holding insulating sheet is fixed to at least one side of the metal foil body, and the heater element is separated from the reinforcing bridge portion. It is characterized in that it is provided with the above-mentioned heat generating unit and a cover insulating plate that is adhered and fixed to both sides of the heat generating unit.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view of an embodiment of a sheet heater according to the present invention, FIG. 2 is an explanatory diagram of its configuration, and FIG. 3 is an explanatory diagram of a heating unit used in the sheet heater of the present invention. Shows.

Before describing the sheet heater according to the present invention,
The heat generating unit shown in FIG. 3 will be described first with reference to the front view of the embodiment of the metal foil body in which the heater element of FIG. 4 is formed.

A heater element 2 as a heating resistor patterned in a predetermined shape on the metal foil base material 1 by punching or etching method and a plurality of reinforcing bridge portions 3 connected to the heater element 2. The metal foil body 4 is formed by forming.

On the whole of the metal foil body 4 or a part of the metal foil base material 1 including the heater element 2 and the reinforcing bridge portion 3, for example, a heat resistant film or an assembled mica prepreg sheet, varnish impregnated glass cloth, etc. The thin holding insulating sheet 5 is set on both sides or one side, and both are adhered and fixed by heat, pressure or heat resistant resin.

The metal foil body 4, which is adhered and fixed on both sides or one side by a thin holding insulating sheet, has the unnecessary reinforcing bridge portion 3 and the metal foil base material 1 removed by pressing or the like, and is punched into a predetermined outer shape. The heating unit 6 shown in FIG. 3 is created.

At the time of punching the outer shape with this press or the like, the punched end of the heater element 2 is punched at a distance of at least 3 mm from the outer shape of the product defined by the Electrical Appliance and Material Control Law, and the outer shape of the heat generating unit 6 is cut. Part of the product has the same outer shape as that of the product to be assembled, and is punched for convenient positioning during assembly.

Since the heater element 2 during the production of the heat generating unit 6 is punched by a press or the like after the thin holding insulating sheet 5 is bonded and fixed under the state of being connected to the reinforcing bridge portion 3. , Heater element 2
The creepage insulation distance is maintained at the original distance when the metal foil body 4 is formed.

For example, the metal foil body 4 shown in FIG. 4 is sandwiched by a 0.1 mm thick silicone resin laminated mica prepreg sheet on both sides, and heated at 100 ° C. and 20 kg / cm ² to generate heat. A master plate for Unit 6 was prepared. After that, the position is determined by using the punching hole 8, the die is punched to form the heat generating unit 6 having a predetermined shape, and the arrangement state of the heater element 2 is observed. Was done.

The unnecessary reinforcing bridge portion 3 and the metal foil base material 1 may be removed and a predetermined outer shape may be formed by a punching machine or a cutting machine. As shown in FIGS. 1 and 2, the heat generating unit 6 thus produced has a cover insulating plate 7 made of a silicone resin laminated mica plate having a thickness of 0.35 mm on both sides thereof, as shown in FIGS. It is closely fixed by the fixing means, and a planar heater that complies with the electrical appliance law is created.

The cover insulating plate 7 is not limited to a silicone resin laminated mica plate having a thickness of 0.35 mm.
It goes without saying that members having other thicknesses and materials may be used.

[0016]

As described above, according to the present invention, the heater element is adhered and fixed with a thin holding insulating sheet before cutting from the reinforcing bridge portion, and then the reinforcing bridge portion is cut. As a result, the entanglement of the heater element is eliminated, its handling is facilitated, and there is no displacement of the heater element, and a heating unit in which the creepage insulation distance of the heater element is secured with high reliability is created.

Therefore, the planar heater using the heat generating unit has high insulation quality. In addition, since it is possible to mechanize, the heating unit and the planar heater can be automated, and mass production is possible, and the cost is reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a planar heater according to the present invention.

FIG. 2 is an explanatory diagram of the configuration of FIG.

FIG. 3 is a structural explanatory view of a heating unit used in the planar heater of the present invention.

FIG. 4 is a front view of an example of a metal foil body on which a heater element is formed.

[Explanation of symbols]

 1 Metal Foil Base Material 2 Heater Element 3 Reinforcement Bridge 4 Metal Foil 5 Retaining Insulation Sheet 6 Heating Unit 7 Cover Insulation Plate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Manabu Abe 1 Okabe Mica Co., Ltd., 1596 659, Naka, Naka, Fukuoka, Japan

Claims (2)

[Claims] 1. A metal foil body comprising a metal foil base material and a plurality of metal foil heater elements patterned in a predetermined shape and a plurality of reinforcing bridge portions, wherein at least the metal foil body is formed. The present invention is characterized by comprising a heat generating unit formed by fixing a thin holding insulating sheet on one surface and then separating a heater element from a reinforcing bridge portion, and a cover insulating plate closely fixed to both surfaces of the heat generating unit. Sheet heater. 2. A metal foil body comprising a metal foil base material and a plurality of metal foil heater elements patterned in a predetermined shape and a plurality of reinforcing bridge portions formed on at least one surface of the metal foil body. A surface which is characterized in that a sheet is fixed, and the heater element is cut off from the reinforcing bridge portion under the state where the heater element is fixed to the thin holding insulating sheet, so that a heating unit is created. Of manufacturing a heating unit of a rectangular heater.