JPH0611310U - coil - Google Patents

Abstract

(57) [Abstract] [Purpose] Two coil bodies made of a ribbon wire are arranged side by side to form one coil so that the coil can be easily manufactured and no protrusion or wrinkle of the ribbon wire is generated inside the coil. . [Structure] Two coil bodies 1 whose winding directions are opposite to each other
a and 1b are coaxially arranged in series while each coil body 1
The innermost thin films 2 and 2 of a and 1b are electrically connected by a conductive metal foil 3 arranged so as to straddle the two coil bodies 1a and 1b. In the two coil bodies 1a and 1b whose winding directions are opposite to each other, a current flowing in the clockwise direction from the conductor portion of the outermost layer of one coil body 1a flows to the other coil body 1b adjacent to the innermost layer portion, Further, while flowing in the clockwise direction, it reaches the outer peripheral side of the coil body, is taken out from the conductor portion of the outermost layer to the external circuit, and magnetic flux in the same direction is generated in the two coil bodies 1a and 1b.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a coil formed by winding a conductive thin film such as copper foil. More specifically, the present invention relates to a coil in which a plurality of coils, each of which is formed by winding a ribbon-shaped conductive thin film, are coaxially overlapped and arranged to function as one coil.

[0002]

[Prior art]

 Conventionally, a stator coil of a motor, for example, a coil of a PM type stepping motor, is generally used by winding a wire (round wire) around a coil bobbin, but with the recent miniaturization of the motor, the coil conductor space is occupied. A coil wound with a strip-shaped conductor (ribbon wire) such as copper foil has been considered because it is necessary to improve the efficiency. However, in the case of this ribbon wire coil, one lead must be taken out from the inside of the coil, and the necessary magnetomotive force can be obtained without increasing the coil volume (do not reduce the number of turns). ) Is difficult. In order to increase the number of turns without changing the coil volume, it is necessary to reduce the thickness of the copper foil as much as possible. However, if the copper foil is too thin, it will be difficult to wind it and it will not be possible to reduce the thickness too much. Therefore, there is a problem that a magnetomotive force cannot be obtained if the coil is downsized.

Therefore, it has come to be considered that two coil bodies formed of ribbon wires are vertically arranged coaxially and function as one coil. Conventionally, an attempt to construct such a coil with a single ribbon wire is disclosed in JP-A-62-260535. In this coil, as shown in FIG. 3 (A), a ribbon wire 101 made of copper foil is folded back in the middle, and the folded portion 102 is started to be wound and two rows of coil bodies are simultaneously wound around the core rod 103 in the same direction. It is turned to form two thin coil bodies 104 and 105 coaxially (see FIG. 3B). Next, after fixing the winding end end 106 of the one coil body 104, the other coil body 105 is unwound and unwound (see (C) and (D) of FIG. 3), and further wound in the opposite direction. A coil body having a winding direction opposite to that of the fixed one coil body is formed (see (E) of FIG. 3). As a result, two rows of coil bodies that are wound in the opposite directions from one ribbon wire and overlapped with each other are formed.

[0004]

[Problems to be solved by the device]

 However, in the case of this coil, the folded-back portion 102 of the ribbon wire 101, which is the winding start, remains clamped by the one coil body 104 that is first wound, so that the folded-back portion 102 projects toward the inside of the coil. Inevitably, it becomes a protrusion. Since the rotor is arranged inside the coil, the presence of this protrusion is not preferable.

Further, after winding the extremely thin and thin ribbon wire 101 to once form the two rows of coil bodies 104 and 105, unwinding one of them 105 and then winding in the opposite direction is a complicated process. Not only is it troublesome, but it is difficult to wind the ribbon wire 101 with high precision, and it is difficult to put it into practical use.

Further, since the folded portion 102 at the beginning of winding of the coil is folded in the opposite direction while being fixed by the one coil body 104, a crack is generated in the folded portion 107 or the folded portion does not work well and is considerably wrinkled. It may become a large protrusion.

An object of the present invention is to provide a coil which can be easily manufactured and which does not have a ribbon wire protrusion or a wrinkle inside the coil.

[0008]

[Means for Solving the Problems]

 In order to achieve such an object, in the coil of the present invention, two coil bodies whose winding directions are opposite to each other are coaxially arranged in tandem while the thin films of the innermost layers of each coil body are formed into two coil bodies. Electrically conductive metal foils are arranged so as to straddle each other. Here, for example, a copper foil or a solder foil is preferably used as the conductive metal foil.

Further, according to the present invention, a plurality of sets of the above-mentioned coils are coaxially overlapped and arranged, and the outermost thin films of one coil body of an adjacent set are electrically connected to function as one coil. I am trying to do it.

[0010]

[Action]

 Therefore, two coil bodies that have been formed separately in advance are stacked with the winding directions of the thin films being opposite to each other, and a copper foil or solder is placed on the thin film of the innermost layer so as to straddle the two coil bodies. When a metal foil such as foil is placed and heated or bonded with a conductive adhesive, a conductive film-like material that connects the two coil bodies is formed between the two coil bodies. At the same time as the coil bodies are joined, it functions as a coil. For example, the current flowing clockwise from the outermost conductor part of one coil body flows to the other coil body adjacent to the innermost conductive metal foil (film), and further in the clockwise direction. While flowing, it reaches the outer circumferential side of the coil body and is taken out from the thin film portion of the outermost layer to an external circuit or the like, and magnetic fluxes in the same direction are generated in the two coil bodies.

[0011]

【Example】

 Hereinafter, the configuration of the present invention will be described in detail based on the embodiments shown in the drawings.

First, the structure of one coil body and its manufacturing method will be described. The coil body is obtained, for example, by slicing a rod-shaped wound body obtained by winding a conductive thin film into a desired width. Although not shown, the rod-shaped wound body made of a conductive thin film is wound around a core jig while applying an adhesive to a conductive thin film such as copper foil with an electrically insulating coating formed on one surface. It is formed by putting on. Here, in order to enable the core jig to be removed, no adhesive is applied to the thin film portion that directly contacts the core jig. In addition, the thin film portion that comes into contact with the winding jig is not pre-formed with an electrically insulating film, or even if it is formed, it will be peeled off in a later step and the It is provided so that the inner surface is not covered by the electrically insulating coating. After the winding is completed, the adhesive is cured to solidify the wound body, and the wound body of the conductive thin film is removed from the winding jig. After that, the cylindrically wound winding body is sliced into a coil body with a predetermined width using a multi-wire saw or the like to obtain a coil body. The multi-wire saw is made by arranging tens to hundreds of wires at a desired pitch as needed. The cut portion of the coil body obtained by slicing is cut or melted by the wire saw to cause an interlayer short circuit. Therefore, a cut surface is formed by etching treatment (this surface is referred to as the side surface of the coil body in this specification). Burrs, etc. are removed. This prevents shorting of the copper foil electrically isolated by the electrical insulation and adhesive. In order to prevent a short circuit between the side surface 4 of the coil body after the etching process and the side surface 4 of another coil body, as shown in FIG. 1C, an electrical insulating material such as an epoxy-based material or a phenol-based material is used. A resin coating 7 is formed.

As shown in FIG. 1, the coil bodies 1a and 1b thus obtained are arranged back to back so that the winding directions of the coils are opposite to each other, and the coil bodies 1a and 1b The thin film portion is electrically connected by the conductive metal foil 3. For example, as shown in FIG. 1 (C), the coil bodies are connected to each other by solder foil, preferably 0.2 mm or less of solder foil so as to straddle one set (two) of coil bodies 1a and 1b. It is carried out by placing the slice 3 and passing it in that state through a reflow furnace. In some cases, as shown in FIG. 1 (D), a piece 3 of a conductive material foil such as a copper foil is placed so as to straddle the two coil bodies 1a and 1b. The conductive adhesive 5 or the like is used for adhesion. The copper foil preferably has a thickness of 100 μm or less and a length shorter than the thickness of two coil bodies. As a result, two coil bodies 1a and 1b whose winding directions of the thin film 2 are opposite to each other are connected in series at the innermost layer portion through the section 3, and the current flows in the same direction but the winding directions are opposite to each other. It becomes the direction coil. For this reason, magnetic fluxes in the same direction are generated in the two coil bodies 1a and 1b, and an effect (magnetomotive force) is obtained such that these two coil bodies 1a and 1b are integrated into a large diameter. Before the adhesion of the conductive metal foil 3, the electrically insulating coating on the inner peripheral surfaces of the two coil bodies 1a and 1b makes it possible to electrically connect the whole or at least two coil bodies 1a and 1b. The gain has been removed. The electric insulating film may be removed by sanding after molding the coil bodies 1a and 1b, or the insulating material at the corresponding position of the conductive thin film before winding may be removed in advance. It is possible.

A flexible substrate, a lead wire 6 or the like is soldered to the thin film 2 in the outermost layer portion so as to be connectable to an external circuit. Further, since the inner peripheral surface of the coil 1 is covered with the conductive foil 3, it is necessary to form the electrically insulating coating 8 on the surface. This electric insulating film 8 is for preventing contact with the magnet of the rotor arranged inside and for preventing short circuit. Further, instead of the electrically insulating film 8, for example, a plastic coil bobbin can be inserted. In addition, a flexible substrate or lead wires 6 are soldered to the thin film 2 in the outermost layer so as to be connectable to an external circuit.

It should be noted that the above-described embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention. For example, in the present embodiment, the case where the two coil bodies 1a and 1b are connected has been mainly described, but the present invention is not particularly limited to this, and two or more coils can be connected if necessary. Is. For example, as shown in FIG. 1, one set of two coils 1 in which the thin film of the innermost layer portion is electrically connected by a conductive foil 3 is arranged in plural sets as shown in FIG. It is also possible to electrically connect the outermost thin films of one coil of the adjacent set to each other by, for example, copper foil 9 and connect two or more sets of coils in series to form one coil. is there.

Further, in the present embodiment, a description has been given mainly of an example in which a coil body having the same winding direction is produced in large quantity by slicing a rod-shaped winding body, and the coils are turned and the combination is connected. There is no particular limitation to this, and a coil body wound in the clockwise direction and a coil body wound in the counterclockwise direction are separately prepared in advance, and these are combined to produce one coil. May be.

Further, in the present embodiment, the two coil bodies have a perfect circular shape, but the present invention is not limited to this. For example, a substantially triangular coil used in a face-to-face motor or the like can be used. Applicable.

[0018]

[Effect of device]

 As is apparent from the above description, in the coil of the present invention, two coil bodies whose winding directions are opposite to each other are coaxially arranged in a column, while the thin films of the innermost layer of each coil body are two coil bodies. Since the electrically conductive metal foils are arranged so as to straddle the body to make the electrical connection, the two coil bodies are butted and the metal foils are placed inside them to electrically connect to each coil body. A coil in which two coil bodies or more coil bodies function as one coil can be easily manufactured by a simple operation of simply connecting. However, since the electrical connection is completed at the same time when the two coil bodies are joined, the connection work is extremely easy. There is no protrusion of the folded ribbon wire or twisting of the ribbon wire in the innermost layer. .

Further, according to the coil of the present invention, it is possible to simplify the winding work by eliminating the useless work of winding the coil once and then unwinding only the other coil and winding again in the opposite direction. At the same time, it is possible to reduce the occurrence of defective products due to defective winding. Moreover, since the coil body obtained by slicing the rod-shaped wound body around which the conductive thin film is wound can be used, the coil can be easily manufactured and the mass productivity is excellent. In particular, when connecting coils wound in the same direction in opposite directions, it is sufficient to manufacture one type of coil body in the winding direction.

Further, since the ribbon wire forming the coil is not folded back or twisted, the coil can be formed using an extremely thin copper foil of several μm, and the space factor of the coil conductor can be reduced. Can be improved. Moreover, according to the coil of the present invention, a crack does not occur in the middle of the coil.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of a coil of the present invention, (A)
Is a perspective view showing one set of coils before connection, (B) is a cross-sectional view showing the coils in a connected state, (C) is an enlarged view showing an exaggerated example of the connected state of the coil body, (D) is a coil It is an enlarged view which exaggerates and shows another example of the connected state of the body.

FIG. 2 is a side view showing another embodiment of the coil of the present invention.

FIG. 3 is an explanatory diagram showing a conventional coil manufacturing method.

[Explanation of symbols]

 1 coil 1a one coil body 1b other coil body 2 thin film (ribbon wire) that constitutes the coil body 3 conductive metal foil 4 side surface of the coil body 5 conductive adhesive

Claims (4)

[Scope of utility model registration request] 1. Two coil bodies whose winding directions are opposite to each other are coaxially arranged in tandem, while thin films of innermost layers of each coil body are arranged so as to straddle two coil bodies. A coil characterized by being electrically connected with a conductive metal foil. 2. The coil according to claim 1, wherein the metal foil is a copper foil. 3. The coil according to claim 1, wherein the metal foil is a solder foil. 4. A plurality of sets of the coils according to claim 1 are coaxially overlapped and arranged, and the outermost thin films of one coil body of an adjacent set are electrically connected to each other to function as one coil. A coil characterized by.