JP2001185940A - Method for manufacturing sheet type antenna coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an economical method which can easily and efficiently manufacture a sheet type antenna coil, reduce the cost, and finish the coil with thin thickness. SOLUTION: The antenna coil is manufactured by forming a spiral coil by winding a conductor spirally around a plane. A winding start end part 3A of a beltlike conductor 3 having its surface coated 4 with a nonconductor is fixed to a nonconductive core material 2 by adhesion or insertion and then rolled; and the nonconductive core material 2 and beltlike conductor 3 are heated and adhered in one body to form a rolled antenna raw material 6, which is sliced in the crossing direction to form sheet type antenna coils 1 having specific spiral coils.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna coil, in particular, a non-contact type IC card (Integrate).
The present invention relates to a method for manufacturing a sheet-like antenna coil incorporated in a dCircuit Card or an IC tag (Integrated Circuit Tag).

[0002]

2. Description of the Related Art An IC card in which an IC chip of a microprocessor and a memory is embedded in a plastic card has a large storage capacity and an arithmetic function, and is expected to be used in various fields. In particular, recently, a non-contact IC card or an IC tag having a built-in antenna coil has attracted attention.

FIG. 6 shows a general method of manufacturing a sheet-like antenna coil by a conventional winding method. FIG.
In the winding method, a round conductor 7 composed of a conductive thin wire (generally a copper thin wire) having an insulating coating on the surface is aligned in a plane and spirally wound to form a spiral winding 8. The spiral antenna coil 9 is finished. The number of turns of the spiral winding 8 is determined by a predetermined number of turns according to a frequency (wavelength) band used by the antenna coil. FIG. 7 is a sectional view taken along line AA of FIG.

In addition to the winding method, as a method of manufacturing an antenna coil, a conductive thin wire is passed through a nozzle, the nozzle is moved in a spiral orbit on an adhesive sheet, and the thin wire is attached to form a coil. Drawing method, paint method in which conductive paint is spirally applied on the sheet by silk screen method to make a coil, masking the part that you want to leave as an antenna using metal foil as a conductor,
There is an etching method in which the remaining portion is removed by etching to form a coil.

[0005]

However, according to the conventional method for manufacturing an antenna coil, there is a problem that each of them is unsuitable in any of the following aspects such as product characteristics, productivity and manufacturing cost. . (1) In the winding method, since a round wire is wound on a plane, it is very difficult to wind the wire in a neatly aligned and spiral manner. In most cases, adjacent wires overlap each other as shown in FIG. The antenna coil itself increases in thickness, and the finished thickness of the card when the antenna is embedded is inevitably thicker, and the antenna characteristics are inferior to other systems, resulting in cost reduction. Is also a problem. (2) Although the drawing method can prevent overlapping of lines, it is not suitable for manufacturing an antenna coil having a long wavelength and a large number of turns. (3) Since the paint method generally uses a silver paste as a conductor, the cost is high, and the paint method is susceptible to distortion such as bending, so that it is not suitable for manufacturing an antenna coil having a large number of turns. (4) The etching method has a low production rate and low productivity (material yield), and requires the use of a chemical. Therefore, it is necessary to manage a liquid that does not dissolve parts other than the antenna and to consider the environment.

Therefore, an object of the present invention is to provide a method of manufacturing a sheet-shaped antenna coil which is easy and efficient to manufacture and can reduce the cost.

Another object of the present invention is to provide an economical method of manufacturing a sheet-like antenna coil which can make the coil thinner.

[0008]

In order to achieve the above object, the present invention provides a method of manufacturing an antenna coil in which a conductor is spirally wound on a plane to form a spiral winding. Core material, a band-shaped conductor having a surface coated with a non-conductor, after winding in a roll shape, the non-conductive core material and the band-shaped conductor,
A method of manufacturing a sheet-shaped antenna coil, comprising forming a predetermined spiral winding by integrally bonding to form a roll-shaped antenna material, and then slicing the roll-shaped antenna material in a cross-sectional direction. I will provide a.

According to the present invention, in order to achieve the above object, the step of spirally winding the strip-shaped conductor around the non-conductive core material comprises the step of: Fixed by bonding to non-conductive core material,
Alternatively, after fixing by insertion, a method for manufacturing a sheet-shaped antenna coil is provided, in which a spiral winding is formed by winding in a roll shape, and the step of forming the roll-shaped antenna material includes the step of forming the strip-shaped conductive material. After the body is wound around the non-conductive core material in a roll shape, the non-conductive core material and the strip-shaped conductor are bonded together by heating to form a spiral winding. A method for manufacturing a sheet-shaped antenna coil is provided.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A manufacturing method according to an embodiment of the present invention will be described with reference to FIGS. 1 to 4 (first embodiment) and FIG. 5 (second embodiment). For example, 88 mm x 56
The sheet-shaped antenna coil embedded in the non-contact type IC card of the mm card size is designed to have a predetermined size in accordance with a frequency (wavelength) band to be adopted, and an appropriate value is set for the thickness of the card.

(First Embodiment) FIG. 1 shows the relationship between a non-conductive core material and a strip-shaped conductor in a method for manufacturing a sheet-like antenna coil according to an embodiment of the present invention. As the non-conductive core material 2, for example, a vinyl chloride resin (PVC) having a circular column is prepared. As the strip-shaped conductor 3, for example, a vinyl chloride resin ( A strip-shaped conductor 3 provided with a non-conductive coating 4 of PVC) is prepared. As shown in FIG. 1, the winding start end 3 </ b> A of the strip-shaped conductor 3 is fixed to the non-conductive core material 2 by an adhesive portion 5 </ b> A by heat welding.

FIG. 2 shows winding of a strip-shaped conductor in a method of manufacturing a sheet-like antenna coil according to an embodiment of the present invention. The belt-shaped conductor 3 having the winding start end 3A fixed to the non-conductive core material 2 is made of a non-conductive core material 2
Is rotated around the non-conductive core material 2 in a roll shape by a predetermined number of turns set according to the frequency (wavelength) to be adopted. When winding the strip-shaped conductor 3 around the non-conductive core material 2, the tension is applied to the strip-shaped conductor 3 while applying a tension equal to or less than the tensile breaking load of the strip-shaped conductor 3. Core material 2
It is realized that the strip-shaped conductor 3 is wrapped neatly.

FIG. 3 shows a roll-shaped antenna material in a method for manufacturing a sheet-shaped antenna coil according to an embodiment of the present invention. Circular pillar vinyl chloride resin (PVC)
The strip-shaped conductor 3 wound in a roll shape around the non-conductive core member 2 made of is then heated. Due to this heating, the non-conductive core material 2 made of a circular column of vinyl chloride resin (PVC) and the strip-shaped conductor 3 provided with a non-conductive coating 4 of vinyl chloride resin (PVC)
As a result, the roll-shaped antenna material 6 is formed. The roll-shaped antenna material 6 in FIG.
A band-shaped conductor 3 is wound around the non-conductive core material 2 by a predetermined number of turns set in accordance with a frequency (wavelength) band to be adopted. Next, the roll-shaped antenna material 6 is sent to a slicing process.

FIG. 4 shows a sheet-like antenna coil manufactured by the manufacturing method according to the embodiment of the present invention.
The sheet-shaped antenna coil 1 is made of a roll-shaped antenna material 6.
Each of the non-conductive core members 2 and the strip-shaped conductors 3 constituting FIG. 3 is manufactured by slicing in a cross-sectional direction (round cutting), and has a thin sheet having a predetermined spiral winding. The formation of the antenna coil 1 is realized. The slice (round slice) of the roll-shaped antenna material 6 (FIG. 3) may be mechanically cut by, for example, a sharp rotary cutter, or may be sliced by processing with high-energy laser light. . For this reason,
The material of the non-conductive core material has a dielectric loss tangent desired for antenna characteristics, and an insulator having good machinability during manufacture is desired.

(Second Embodiment) FIG. 5 shows the relationship between a non-conductive core material and a strip-shaped conductor in a method for manufacturing a sheet-like antenna coil according to another embodiment of the present invention. As the non-conductive core material 2, for example, a vinyl chloride resin (PVC) having a circular column is prepared. As the strip-shaped conductor 3, for example, a vinyl chloride resin ( A strip-shaped conductor 3 provided with a non-conductive coating 4 of PVC) is prepared. FIG.
As shown in the figure, the non-conductive core material 2 is provided with an insertion groove 5B in the longitudinal direction of the circular column, and the winding start end 3A of the strip-shaped conductor 3 is inserted into the insertion groove 5B and fixed. Have been. The subsequent manufacturing process of the antenna coil according to the second embodiment shown in FIG. 5 will be described with reference to FIGS.
By the same steps as described above, the desired sheet-like antenna coil (same configuration as the coil in FIG. 4) is formed,
Description is omitted.

According to the embodiment of the present invention, the non-conductive core material, the non-conductive coating material, and the strip-shaped conductor constituting the antenna coil are all radio waves used in the antenna coil, for example, This material is suitable for frequency bands such as medium wave (MF) or very high frequency (VHF) and is easy to manufacture.

In the embodiment of the present invention, the shape of the core material is preferably a circular column, an elliptical column, a polygonal column, or the like, and the non-conductive material constituting the core material has a small dielectric loss tangent. Dielectric, ie, electrically insulating, materials are suitable. An electrically insulating material such as an electrically insulating synthetic resin or a natural resin, for example, a vinyl chloride resin (PVC), a polyurethane resin, or a natural rubber can be used.

In the embodiment of the present invention, the non-conductive material used for the coating material is a dielectric material, that is, a material of an electrical insulator, and is referred to as a synthetic resin,
Alternatively, not only a general electric insulator such as a natural resin or an electric insulating paint, but also an electric insulating oxide film or the like is included, and a flexible and widely-defined electric insulating material can be used. As the non-conductive synthetic resin, for example, a film such as a vinyl chloride resin (PVC) or polyester is used, and an electrically insulating paint film such as a polyurethane resin, a phenol resin, a silicone resin, or an epoxy resin can also be used. Examples of the electrically insulating oxide film include copper oxide and aluminum oxide.

As the strip-shaped conductor in the embodiment of the present invention, a copper strip, a copper foil, an aluminum foil or the like is used. Further, as a means for fixing the non-conductive coated strip-shaped conductor to the non-conductive core material, when the winding start end of the strip-shaped conductor is bonded, welding by heating, fusion by dielectric heating, Adhesion with an adhesive or the like is used.

[0020]

According to the method for manufacturing a sheet-shaped antenna coil of the present invention, the winding start end of a strip-shaped conductor having a surface coated with a non-conductor is fixed to a non-conductive core material and then formed into a roll. After winding, a non-conductive core material and a band-shaped conductor are bonded together by heating to form a roll-shaped antenna material, and then the roll-shaped antenna material is sliced in a cross-sectional direction (round cutting) to form one. From this roll-shaped antenna material, a large number of sheet-shaped antenna coils having a predetermined spiral winding can be manufactured at one time. In particular, a sheet-shaped antenna coil can be formed from one roll-shaped antenna material by slicing, for example, 100 sheets, 200 sheets, or the like.
There is an effect that an extremely thin antenna coil suitable for being embedded in a card can be provided with high efficiency, high productivity, and low cost.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a relationship between a non-conductive core material and a strip-shaped conductor in a method for manufacturing a sheet-shaped antenna coil according to an embodiment of the present invention.

FIG. 2 is a perspective view showing winding of a strip-shaped conductor in a method for manufacturing a sheet-like antenna coil according to an embodiment of the present invention.

FIG. 3 is a perspective view showing a roll-shaped antenna material in a method for manufacturing a sheet-shaped antenna coil according to an embodiment of the present invention.

FIG. 4 is an explanatory sectional view showing a sheet-like antenna coil manufactured by the manufacturing method according to the embodiment of the present invention;

FIG. 5 is a perspective view showing a relationship between a non-conductive core material and a strip-shaped conductor in a method for manufacturing a sheet-shaped antenna coil according to another embodiment of the present invention.

FIG. 6 is an explanatory view showing a method of manufacturing a sheet-like antenna coil by a conventional winding method.

FIG. 7 is a sectional view taken along the line AA of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet-shaped antenna coil 2 Non-conductive core material 3 Strip-shaped conductor 3A Winding start end 4 Non-conductive coating 5A Adhesive part 5B Insertion groove 6 Roll-shaped antenna material 7 Round conductor 8 Spiral winding 9 Spiral Antenna coil

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01Q 7/06 G06K 19/00 K (72) Inventor Masahiro Nagai 5-1-1 Hidakacho, Hitachi City, Ibaraki Prefecture No. 1 Hitachi Cable, Ltd. Power System Laboratory F-term (reference) 2C005 MA18 MB10 NA08 PA18 PA27 TA22 5B035 AA04 BB09 CA01 CA23 5J046 AA01 AA19 AB11 AB12 PA06 PA07 QA01

Claims (3)

[Claims] 1. A method of manufacturing an antenna coil in which a conductor is spirally wound on a plane to form a spiral winding, wherein a non-conductive core material is coated with a non-conductor on the surface. Is wound in a roll shape, the non-conductive core material and the strip-shaped conductor are bonded together to form a roll-shaped antenna material, and then the roll-shaped antenna material is sliced in a cross-sectional direction. A method for manufacturing a sheet-shaped antenna coil, wherein a predetermined spiral winding is formed. 2. The step of spirally winding the strip-shaped conductor around the non-conductive core material comprises fixing the winding start end of the strip-shaped conductor by bonding to the non-conductive core material. 2. The method for manufacturing a sheet-like antenna coil according to claim 1, wherein the spiral winding is formed by forming the spiral coil after fixing by inserting or by inserting. 3. The step of forming the roll-shaped antenna material includes winding the strip-shaped conductor around the non-conductive core material in a roll shape, and then rolling the non-conductive core material and the strip-shaped conductor. 2. The method for manufacturing a sheet-like antenna coil according to claim 1, wherein the spirally wound winding is formed by heating and bonding together.