JPS5832242Y2 - metal foil resistor - Google Patents

Description

[Detailed description of the invention] The present invention relates to a metal foil resistor, and aims to provide a metal foil resistor suitable for high power applications, which is composed of a substrate serving as a supporting base, a metal foil, and an adhesive for bonding these together. That is.

Conventionally, wire-wound resistors have been used as high-power resistors.

There are fixed resistors and variable resistors, but metal wire-wound resistors cannot avoid residual inductance and capacitance components, and variable resistors also have resolution, There were problems with characteristics such as sliding noise.

In order to prevent this, if a resistive metal foil is pasted on a substrate, a resist layer is formed on it, etched, and unnecessary parts are removed to create a metal foil resistor. Since an adhesive layer is formed on the substrate, there are disadvantages such as lowering the surface insulation of the base material, causing electrolytic corrosion, and easily adsorbing dirt.

The present invention aims to provide a metal foil resistor that has stable performance and can be mass-produced.

The substrate that becomes the support according to the present invention is a metal plate such as an iron plate, a copper plate, or an aluminum plate, and is made of epoxy resin, polyimide resin, etc.
A film made of unsaturated polyester resin, triazine resin, fluororesin, etc. is used.

Also, the adhesive used for this is epoxy resin, phenolic resin,
Single or mixed adhesives such as silicone resins and alkyd resins, as well as modifying resins such as butyl rubber and nitrile rubber, can be used.

A substrate made by adhering a film to metal foil is heat resistant, has excellent heat dissipation properties even when used for high-load power applications, and has excellent dimensional stability and mechanical strength.

The resistance foil is 80 Ni-20Cr. 75 Ni
-20Cr-3Al-2Cu, 35 Ni-20Cr-
45Fe.

80 Fe-15Cr-5Al, 85 Cu-10
Many types of resistive materials such as Mn-5Ni can be used.

In addition, adhesives for the metal foil include single resins such as phenol formaldehyde, resorcinol formaldehyde, epoxy, silicone, and alkyd, and composite resin adhesives such as phenol formaldehyde nitrile rubber, phenol formaldehyde vinyl acetal, and resorcinol polyamide. be able to.

The thickness of this adhesive layer is preferably 10 to 40 μm.

If the adhesive layer is thinner than 10 μm, there may be pinholes or uneven coating may occur, resulting in non-uniform adhesion.

Moreover, if it exceeds 40 μm, the adhesive may flow out to unnecessary areas or the adhesion itself may deteriorate.

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a resistance foil and 2 is an adhesive layer, and the adhesive used is one that has been applied to the resistance foil 1 in advance.

3 is a metal plate made of iron, copper, etc., 4 is a resin film, and the metal plate 3 and the resin film 4 are bonded together by an adhesive layer 5.

Reference numeral 6 indicates a mold having a blade mold 7 shaped like a resistor pattern.

As shown in FIG. 2, the resistance foil 1 punched out by this mold 6 is mechanically extremely strong because it is fixed by the adhesive layer 2 to the substrate surface, which is a metal plate 3 with a surface resin film. , perfect against warping, twisting, impact, etc.

Furthermore, since the adhesive layer 2 is not attached to the surface of the resin film 4 that is not electrically in contact with the resistance foil 1, moisture adsorption does not occur, and the insulation properties of the film itself are guaranteed. Therefore, electrolytic corrosion does not occur, and flame retardancy is achieved.

As mentioned above, this invention uses a resin film bonded to a metal plate, so it is not only suitable for high power applications, but also has excellent dimensional stability9 mechanical strength, and It has good smoothness and has excellent performance as a variable resistor.

In addition, the present invention has adhesive only in the areas necessary for attaching the resistance foil, and if the thickness of the adhesive layer is appropriate, the base material and the resistance foil can be firmly bonded, and mechanically, It is a resistor that is electrically and chemically stable.

This resistor can be easily mass-produced, does not emit any harmful substances such as etching liquid during the manufacturing process, is extremely rational and economical, and is a high-power type. A resistor with stable performance and long life can be realized.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the manufacturing procedure of an embodiment of a metal foil resistor according to the present invention, and FIG. 2 is a sectional view of the embodiment. 1... Resistance foil, 2... Adhesive layer, 3.
...Metal plate, 4...Resin film, 5.
...adhesive layer.

Claims (1)

[Scope of utility model registration request] Resistance foil is pasted with adhesive on a substrate made of a resin film laminated onto a metal plate, and the thickness of this adhesive layer is 10 mm.
A metal foil resistor characterized in that it has a thickness of ~40 μm.