JPH0584142B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a flat air-core coil for use in a combination of a plurality of flat air-core coils as a drive coil of a motor or the like.

[Prior Art] Conventionally, this type of flat air-core coil has most commonly used an insulating coated electric wire with a circular cross section wound around a winding core of a desired shape and a desired number of turns.

[Problem to be solved by the invention]

However, the conventional flat air core coil
As shown in the figure, even if the winding is possible with the least amount of air gaps, the cross-sectional area will be larger than the required number of turns because the space factor occupied by the conductor 1 in the cross-sectional area cannot be kept high. There was an inconvenience.

That is, in FIG. 4, the radius of the wire including the insulating layer 2 is R ₁ , and the radius of the conductor 1 in the wire is R1.
Assuming R ₂ , the ratio of the cross-sectional area of the conductor 1 to the cross-sectional area (space factor) is 3πR ₂ ² /6×√3R ₁ ² ×100 = 90.69%, which is calculated by R ₁ and R This is an ideal value when the values of ₂ are equal, but in reality there is a space between the wires, so the value is lower than this.

The space factor of the conductor 1 in the wire differs slightly depending on the wire used, but for example, when a copper wire with a diameter of 0.17 mm is used as the conductor 1, the maximum finished diameter of the polyurethane-coated copper wire is Since it is 0.214mm,
It is 69%.

Therefore, even in an ideal case, the area ratio occupied by the conductor 1 in the cross-sectional area of the flat air-core coil is 90.69% x 69% ≒ 62%, and in reality it is usually around 50%. At best, it is only 60%, and the space factor of the conductor 1 in flat air-core coils used in cassette record players and the like is also about 60%.

Therefore, as shown in Figure 5, an insulating coated copper wire with a circular cross section is crushed flat using a roll machine, etc.
A method of winding this around a core has also been proposed.

Also in this case, since the material of the wire is an insulating coated copper wire, the space factor of the wire itself remains unchanged, and the space factor of the conductor 1 as a flat air-core coil cannot exceed 70%.

In addition, since the insulating layer 2 is rolled with a roller or the like, if the aspect ratio of the cross section is increased, the insulating layer 2
The conductor 1 with a diameter of 0.17 mm cannot be flattened very much, as this may damage the conductor and cause an interlayer short circuit.
Since it is about 0.022 mm, the thickness of the conductor 1 becomes smaller than the thickness including the insulating layer 2, which results in a decrease in the space factor, which is not preferable.

Furthermore, if the diameter of the conductor 1 varies, the variation in the width of the crushed wire increases, so that the width of the wound flat air-core coil as a whole does not fall within a predetermined width. In the case of a flat air-core coil used as part of a magnetic circuit, the gap between the flat air-core coil and the magnet increases in some areas, resulting in a decrease in magnetic efficiency. I end up.

Recently, as shown in FIG. 6, a metal thin film is pasted on a thin insulating sheet 4, a predetermined pattern is printed on this metal thin film, or a predetermined pattern is printed on the metal thin film, or a predetermined coil shape is formed by etching after photoresist processing. It has been proposed to use a required number of printed coils with a thin metal film left on top of them.

However, since this coil is formed as described above, the width of the metal thin film that becomes the coil is 3.
Since this requires a large dimension relative to the thickness of the thin film, it cannot be used for a coil that requires a large number of turns even if the insulating sheets 4 are piled up.

In addition, when considering productivity, insulating sheet 4
Since it is difficult to reduce the thickness to 0.01 mm or less, there remains the disadvantage that no improvement in the space factor can be expected.

Therefore, the present applicant has proposed Japanese Patent Application No. 58-073729 and Japanese Patent Application No. 58-073 to improve the above-mentioned disadvantages.
Nos. 249126 to 249131 were proposed.

This application involves winding a wide copper foil around a winding core, insulating and adhering the copper foils together with an insulating agent or adhesive, and then removing the winding core or cutting it together with the winding core into a desired width. be.

By the way, in the case where the core is removed and cut, there is a possibility that the shape may collapse during cutting, so it requires time and effort to solidify with a shape-retaining material, and in the case where the core is also cut. This had the disadvantage that the winding core could only be used once, increasing material costs (parts costs).

This invention was made in order to solve the above-mentioned conventional disadvantages, and it is possible to increase the space factor of the conductive thin strip, define its outer shape, and increase the number of turns. High efficiency,
The present invention provides a method for manufacturing a flat air-core coil that can be of high quality.

In addition, there is no short circuit between the winding layers due to burrs on the cut end surface, burrs can be removed relatively easily, and lead wires can be easily soldered directly to the conductive thin strip. It provides:

[Means to solve the problem]

In order to achieve the above-mentioned object, the method for manufacturing a flat air core coil according to the present invention includes an insulating layer that has a softening point lower than that of solder and insulates between each wound layer of a conductive thin strip, and an insulating layer that has a softening point lower than that of solder. A wide three-layer thin strip, which has a softening point lower than the softening point and has an adhesive layer that bonds the insulating layer and the thin strip, is cut into a predetermined width using a cutting machine such as a slitting machine, and the cut three-layer thin strip is After winding the strip into a predetermined shape, burrs on the cut end surface of the cut three-layer thin strip were removed by etching, or burrs on the cut end surface of the cut three-layer thin strip were removed by etching. After that, the cut three-layer ribbon is wound into a predetermined shape, and the side end surfaces of the three-layer ribbon wound into a predetermined shape are insulated, and then the inner peripheral end of the wound conductive ribbon is A lead wire or the like is soldered to the outer peripheral end.

[Effect]

The method for manufacturing a flat air-core coil according to the present invention insulates and adheres the ribbon by providing an insulating layer and an adhesive layer on the ribbon, thereby eliminating unnecessary space and increasing the space factor of the ribbon. By making the outer shape more regular and increasing the number of turns, high efficiency and high quality can be achieved.

In addition, since the three-layer thin strip is cut to a predetermined width and either deburred or wound is performed first, there is no short circuit between the winding layers due to burrs on the cut end surface, and burr removal can be performed relatively easily. .

Furthermore, since the softening point of the insulating layer and adhesive layer is lower than that of the solder, lead wires can be easily soldered directly to the conductive ribbon without peeling off the insulating layer or adhesive layer. can.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3.

First, it is rolled to a thickness of 10μm~20μm, then 50mm~
Copper foil a with a width of about 200 mm is as shown in Figure 1 A.
It is sent out from the supply reel 5 at a speed of about 20 m to 50 m per minute.

One side of the sent-out copper foil a is in contact with an application roller 6 in an insulating agent tank 7 containing a heat-softening insulating agent made of, for example, urethane epoxy resin, which will not be corroded by etching. A guide is in contact with the application roller 6, and the excess insulating agent is removed by the guide, and an insulating layer b of a certain thickness is applied to one side of the copper foil a.

The insulating layer b thus applied is heated by a heater 8 to volatilize the solvent and solidify the insulating agent, and then is wound onto a take-up reel 9.

Next, as shown in FIG.
It is sent out toward the adhesive tank 10 at a speed of about 50 m.

This copper foil a is in contact with a coating roller 6 in an adhesive tank 10 containing a urethane epoxy resin having a softening point lower than that of the insulating agent on its lower surface, that is, the surface opposite to the insulating layer b. 6 is in contact with a guide, excess adhesive is removed by the guide, and adhesive c of a certain thickness is applied to the lower surface of copper foil a.

The adhesive layer c thus applied is heated by the heater 8 to volatilize the solvent and solidify the adhesive, and then is wound onto the take-up reel 11.

In this way, the insulating layer b and the adhesive layer c are formed, and the copper foil a having a width of about 20 mm to 50 mm is wound on the take-up reel 11, and is cut into a predetermined width by the slitting roller 12, as shown in FIG. 1C. take-up reel 11
from there to the slitter roller 12.

The slitter roller 12 is composed of two rollers in which large-diameter disks and small-diameter disks of the same width are arranged alternately, and the large-diameter disk of the other roller is inserted into the small-diameter disk of one roller. The copper foil a inserted between the two rollers is cut to fit the pitch width of the disc.

The copper foils d (FIG. 3) cut to a certain width in this manner are respectively wound onto separate take-up reels 13.

The insulating layer b and the adhesive layer c are formed on the copper foil d, which is cut into a predetermined width and placed on the winding frame 1 as shown in FIG. 1D.
It is rolled up to 7.

That is, the copper foil d sent out from the take-up reel 13 is moved by the guide roller 15 having the spring 14.
A certain tension is applied by passing through the
The adhesive layer c is slightly softened by the heater 16,
After being heated to the extent that it has adhesive strength, the winding frame 1
7 for the required number of turns.

By winding the copper foil around the winding frame 17, the adhesive layer c adheres the copper foil d and the insulating layer b, thereby maintaining the wound shape.

Thereafter, after waiting for the adhesive layer c to solidify, it is taken out from the winding frame 17, and as shown in FIG.
After the contamination is washed away, it is immersed in an etching tank 20 containing an etching solution such as ferric chloride (Fecl ₃ ) or nitric acid (HNO ₃ ).

This etching step dissolves the burrs caused by cutting and the copper powder generated in the subsequent process, etches the cut end surface of the copper foil d, prevents short circuits between the wound layers, and returns it to the cleaning tank 19. Immerse to clean the etching solution.

Next, when cleaning of the etching solution is completed, the cleaning solution is placed in a drying oven 21 and dried, and then, as shown in FIG.
An insulating layer b is also formed on the end face of the coil, that is, on the side end face of the coil, and then dried in a drying oven 23.

Thereafter, although not shown in the drawings, lead wires and the like are soldered to the inner and outer peripheral ends of the wound three-layer ribbon copper foil d.

When soldering lead wires etc. to copper foil d in this way, the softening points of insulating layer b and adhesive layer c are lower than the softening point of the solder, so it is easy to solder lead wires etc. directly to copper foil d. Can be soldered.

That is, lead wires and the like can be easily soldered directly to the copper foil d without peeling off the insulating layer b and the adhesive layer c.

Note that even if the cleaning and etching steps of the above-described embodiments are performed while the copper foil d is wound on the take-up reel 13 before being wound on the winding frame 17, as shown in FIG. 2, no problem will occur. do not have.

Further, although the method for manufacturing a flat air-core coil for a motor has been described, it goes without saying that the present invention can also be applied to a method for manufacturing a coil for a speaker and a method for manufacturing a coil for a pickup section of a laser disc player.

〔Effect of the invention〕

As explained above, according to the present invention, an insulating layer that has a softening point lower than that of solder and insulates between each wound layer of the conductive thin strip has a softening point lower than that of solder, A wide 3-layer ribbon on which an adhesive layer is formed to bond the insulating layer and the ribbon is cut into a specified width using a cutting machine such as a slitting machine, and the cut 3-layer ribbon is wound into a specified shape. , removing burrs on the cut end surface of the cut three-layer ribbon by etching, or removing burrs on the cut end surface of the cut three-layer ribbon by etching, and then cutting the three-layer ribbon Since it is wound into a predetermined shape, the space factor of the conductive thin strip can be increased, its outer shape can be defined, and by increasing the number of turns, high efficiency and high quality can be achieved. There is no short circuit between the winding layers due to burrs on the cut end surface, and burrs can be removed relatively easily.

In addition, after insulating the side edges of the three-layer thin strip wound into a predetermined shape, lead wires and the like are soldered to the inner and outer edges of the wound three-layer conductive thin strip. , lead wires and the like can be easily soldered directly to the thin strip without peeling off the insulating layer and the adhesive layer.

[Brief explanation of the drawing]

Figure 1 is a process diagram showing one embodiment of this invention, Figure 2 is a process diagram showing another embodiment of this invention, and Figure 3 is a process diagram showing another embodiment of this invention.
The figure is a cross-sectional view of cut copper foil, Figure 4 is an explanatory diagram of the space factor of a coil using a conventional wire rod with a circular cross section, and Figure 5 is a cross-sectional view when the wire rod with a circular cross section is flattened. FIG. 6 is an explanatory sectional view of the printed coil. a... wide copper foil, b... insulating layer, c... adhesive layer, d... cut copper foil, 12... slitting roller, 17... winding frame, 20... etching tank, 2
2...Insulating agent tank.

Claims (1)

[Claims] 1. An insulating layer having a softening point lower than that of solder is formed on one side of a conductive thin strip, and an adhesive layer having a softening point lower than that of solder is formed on the other side of the thin strip. a cutting step of cutting the wide three-layer thin strip on which the insulating layer and the adhesive layer are formed into a predetermined width using a cutting machine such as a slitting machine; After winding the three-layer ribbon into a predetermined shape, the burrs on the cut end face of the cut three-layer ribbon are removed by etching, or the burrs on the cut end face of the cut three-layer ribbon are removed by etching. a winding/burr removal step of winding the cut three-layer ribbon into a predetermined shape after removing it by etching; and insulating the side end surfaces of the three-layer ribbon wound into the predetermined shape. and a lead wire soldering step of soldering a lead wire or the like to the inner peripheral end and the outer peripheral end of the wound conductive thin strip. Method of manufacturing air core coil.