JPH05243056A - Laminated coil - Google Patents

Abstract

PURPOSE:To provide a laminated coil for use in varieties of electric devices, sail coil being inexpensive and excellent in productivity and possessing a conductor space factor with out losing interlayer insulation and said coil being capable of dealing with a reflow furnace operable at a specific temperature or higher by solving problems of the high cost of a winding material, the low productivity, and the low conductor space factor. CONSTITUTION:A metal foil 1 such as copper or aluminum is employed for a conductor layer of a winding material, and a 500kg/mm<2> or more Young' s modulus and 10mum or less thickness polyethylene naphthalate(PEN) film 2 is employed. Hereby, there is constructed a laminated coil which is inexpensive in the material cost and which is capable of dealing with a reflow furnace operable at 250 deg.C or higher, of realizing a high space factor, and of high speed and easy winding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated coil, and more particularly to a laminated coil used in motors, transformers and the like.

[0002]

2. Description of the Related Art In recent years, as this type of laminated coil, a so-called record winding is used in which an insulated wire having a rectangular cross section coated with a self-bonding layer (hereinafter referred to as a rectangular wire) is wound around a so-called record winding. The conventional laminated coil will be described below.

In FIGS. 3 (a) and 3 (b), 4 is a metal wire, 5 is an insulating coating, and 6 is a self-fusion layer.

The structure of the laminated coil constructed as described above will be described below. First, FIG. 3 (a)
The metal wire 4 shown in Fig. 3 is coated with the insulating coating 5 and the self-bonding layer 6 on a rectangular wire while being heated by hot air or the like, and wound into a so-called record winding to form a laminated coil whose cross section is shown in Fig. 3B. To get In the structure of the laminated coil thus obtained, the insulating coating 5 around the metal wire 4 provides interlayer insulation of the metal wire 4. A self-fusing layer 6 that is fused by heating is present between the insulating coatings 5.

[0005]

However, in the above-mentioned conventional structure, the flat wire made of the material is expensive, and two layers of the insulating coating 5 and almost two layers of the self-bonding layer 6 are provided between the metal wires 4. Since the thickness of the laminated coil is enough, the conductor space factor (hereinafter, space factor) in the cross section of the laminated coil is remarkably reduced, which hinders the high performance of the laminated coil. Furthermore, the rectangular wire has poor tensile strength and is easily meandered and wound up during the process of winding a record. In order to prevent the dimensional accuracy of the laminated coil from deteriorating due to meandering, there is a problem that the winding speed is slow and the productivity is poor because the self-bonding layer is wound while being heated and wound by hot air. Was.

The present invention solves the above-mentioned conventional problems and is inexpensive, has a high conductor space factor, is excellent in productivity, and is compatible with reflow furnaces of 250 ° C. or higher without impairing interlayer insulation. An object is to provide a laminated coil.

[0007]

In order to achieve this object, the laminated coil of the present invention uses a metal foil of copper or aluminum for the conductor layer and has a Young's modulus of 500 kg / mm for the insulating layer.
A PEN film having a thickness of ² or more and a thickness of 10 μm or less is used.

[0008]

With this structure, since the metal foil is used for the conductor layer and the PEN film is used for the insulating layer, the material cost is low, the thin metal ribbon (hereinafter, ribbon) which is a winding material is inexpensive, and the laminated coil is It is compatible with reflow ovens of 250 ° C or higher. The thickness of the PEN film used for the insulating layer is 10 μm.
By setting it to m or less, a high space factor can be realized. Further, by using a PEN film having a Young's modulus of 500 kg / mm ² or more, the tensile strength of the ribbon is increased and the winding can be performed easily at high speed.

[0009]

【Example】

(Embodiment 1) A laminated coil according to an embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 (a) and 1 (b), 1 is a metal foil, 2 is a PEN film, and 3 is a laminating adhesive.

The structure of the laminated coil constructed as described above will be described below. As shown in FIG. 1A, the PEN film 2 is laminated with the adhesive 3 on only one surface of the metal foil 1. In the experiment, two types of rolled copper foil of 35 μm and 18 μm were used for the metal foil 1, and 5 μm was used.
A ribbon was used in which m-thick PEN films were each laminated with a 2 μm-thick adhesive. Of course, it is also possible to use a method of forming a metal layer on the PEN film by using any of vapor deposition, sputtering, plating, or a combination thereof without using an adhesive. When the ribbon is wound as shown in FIG. 1B, a high space factor can be obtained because only two layers, that is, the PEN film 2 of the insulating layer and the adhesive 3 are present between the layers of the metal foil 1. .. PE between metal layers
Since the N film 2 is interposed, the insulation is high and reliable. The space factor of the laminated coil obtained by winding the ribbon used in the experiment was 83% when the 35 μm copper foil was used.

Table 1 shows that PEN is used as the insulating layer of the laminated coil.
This is a comparison of suitability in consideration of various characteristics when a film is used and various characteristics when another plastic film is used.

[0013]

[Table 1]

Polyphenylene sulfide (PPS) film has excellent heat resistance, but is not suitable in terms of mechanical properties, weather resistance and cost. In particular, sulfur contained in the PPS film causes a change in electric resistance of the coil due to corrosion or migration of copper, and therefore cannot be used as a laminated coil material. Polyethylene terephthalate (PET) film is excellent in weather resistance and inexpensive in price, but has low heat resistance and is not suitable for reflow, and since it has a low Young's modulus, high tension cannot be applied during winding. Polyimide (PI)
Although the film is slightly unstable in winding property but has other properties, the price of the film is higher than other films, and the PI film with a thickness of 10 μm or less is more expensive, which affects the price of the coil. Is big.

On the other hand, the PEN film is excellent as a material for the laminated coil because it is excellent in heat resistance, mechanical properties and weather resistance and is inexpensive.

The laminated coil shown in FIG. 2 has 35 μm and 18 μm.
Two types of rolled copper foil with a thickness of m are laminated on a PEN film with a thickness of 5 μm using an adhesive with a thickness of 2 μm on average, and then slit into a width of 1.2 mm.
The ribbon using the copper foil of m has a good winding accuracy in the tension region of about 6 N or more, and the ribbon using the copper foil of 18 μm has a winding region of about 3 N or more in the tension region. To achieve winding in this tension region, Young's modulus is 50
It is considered necessary to laminate a PEN film of 0 kg / mm ² or more.

According to the laminated coil of this embodiment, a laminated coil having a heat resistance of at least 230 ° C. or higher can be realized as a chip component.

[0018]

As is apparent from the above description of the embodiments, according to the laminated coil of the present invention, a metal foil such as copper or aluminum is used for the conductor layer and the Young's modulus is 5 for the insulating layer.
By using a PEN film with a thickness of 00 kg / mm ² or more and a thickness of 10 μm or less, it is inexpensive, has a high conductor space factor, does not impair the interlayer insulation property, and has excellent productivity,
It is possible to realize a laminated coil that can be applied to the above reflow furnace.

[Brief description of drawings]

FIG. 1A is a sectional view showing a concept of a sectional structure of a ribbon used in a laminated coil according to an embodiment of the present invention. FIG. 1B is a sectional view showing a concept of a sectional structure of a laminated coil obtained by winding the ribbon.

FIG. 2 is a graph showing the elongation of the ribbon with respect to a tensile load.

FIG. 3 (a) is a cross-sectional view showing the concept of a cross-sectional structure of a rectangular wire used in a conventional laminated coil, and (b) is a cross-section showing the concept of a cross-sectional structure of a laminated coil obtained by winding a rectangular wire. Figure

[Explanation of symbols]

 1 Metal foil 2 PEN film

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[Procedure amendment]

[Submission date] September 28, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007]

In order to achieve this object, the laminated coil of the present invention has a conductor layer made of copper or aluminum .
Using the throat of the metal foil, and the Young's modulus in the insulating layer is 500kg
/ Mm ² or more are using the following PEN film thickness of 10 [mu] m.

Claims (4)

[Claims] 1. A laminated coil having a copper or aluminum metal foil as a conductor layer and a polyethylene naphthalate (PEN) film as an insulating layer. 2. The laminated coil according to claim 1, comprising a PEN film having a thickness of 10 μm or less. 3. A PEN having a Young's modulus of 500 kg / mm ² or more.
The laminated coil according to claim 1, comprising a film. 4. The laminated coil according to claim 1, which has a heat resistance of at least 230 ° C. or higher that can be used as a chip component.