JP6342092B1 - Coil body, stator, rotating machine, and manufacturing method of coil body - Google Patents

Abstract

The coil body is wound in a plurality of turns and formed into a cylindrical printed circuit board (1) having a plurality of layers, and the printed circuit board (1) arranged in the circumferential direction of the printed circuit board (1) formed into a cylindrical shape. And a plurality of spiral wiring patterns (20) formed on the substrate. When viewed along the radial direction of the printed circuit board (1) formed into a cylindrical shape, the wiring patterns (20) formed in each layer of the plurality of layers overlap each other, and the wiring formed in each layer of the plurality of layers The patterns (20) are electrically connected to each other, and the wiring pattern (20) formed in the outer peripheral layer than the wiring pattern (20) formed in the inner peripheral layer among the plurality of layers, The length along the circumferential direction is long.

Description

  The present invention relates to a coil body, a stator, a rotating machine, and a method of manufacturing a coil body using a printed circuit board on which a wiring pattern is formed.

  Conventionally, it is known that a printed circuit board on which a wiring pattern is formed is wound a plurality of times and formed into a cylindrical shape as a coil body used for a stator of a rotating machine. Patent Document 1 discloses a coil body in which a printed circuit board having a wiring pattern formed in a spiral shape is wound into a cylindrical shape. By forming the printed circuit board into a cylindrical shape, the wiring pattern portion formed in a spiral shape functions as a coil of the rotating machine.

  Further, in Patent Document 2, the interval between a plurality of spiral wiring patterns formed side by side on a printed circuit board is adjusted so that the wiring pattern formed on the inner layer matches the center of the wiring pattern formed on the outer layer. The configuration is disclosed. By providing a conductive core on the outer peripheral side of such a coil body, a stator of a rotating machine can be obtained. And it can be set as a rotary machine by providing the rotor made rotatable in the inner peripheral side of a coil body.

JP-A-55-147936 Japanese Utility Model Publication No.59-173449

  In a rotating machine using a coil body formed of a printed board, it is desired to facilitate the control of current.

  The present invention has been made in view of the above, and an object thereof is to obtain a coil body capable of facilitating current control.

  In order to solve the above-described problems and achieve the object, the present invention provides a printed circuit board that is wound a plurality of times and formed into a cylindrical shape having a plurality of layers, and a circumferential direction of the printed circuit board that is formed into a cylindrical shape. And a plurality of spiral wiring patterns formed along the printed circuit board. When viewed along the radial direction of the printed circuit board formed into a cylindrical shape, the wiring patterns formed in each layer of the plurality of layers overlap, and the wiring patterns formed in each layer of the plurality of layers electrically The wiring pattern formed in the outer peripheral layer is longer in the circumferential direction than the wiring pattern formed in the inner peripheral layer among the plurality of layers.

  The coil body according to the present invention has an effect of facilitating current control.

The perspective view of the rotary machine concerning Embodiment 1 of this invention. The figure which looked at the rotary machine in Embodiment 1 along the central axis The schematic diagram which looked at the coil body in Embodiment 1 along the central axis Plane development of the printed circuit board in the first embodiment The figure which shows the modification 1 of the printed circuit board shown in FIG. The figure which shows the modification 2 of the printed circuit board shown in FIG.

  Hereinafter, a coil body, a stator, a rotating machine, and a method for manufacturing a coil body according to embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a perspective view of a rotating machine according to a first embodiment of the present invention. The rotating machine 30 includes a cylindrical stator 40 and a rotor 50 that is provided inside the stator 40 and is rotatable about the central axis C of the stator 40. Although not shown in FIG. 1, the rotating machine 30 includes a case that accommodates the stator 40 and the rotor 50.

  FIG. 2 is a view of the rotating machine 30 according to the first embodiment viewed along the central axis C. FIG. The stator 40 includes a core 41 and a coil body 42. The core 41 has a cylindrical shape and covers the outer peripheral side of the stator 40. The core 41 is formed of a conductor. The coil body 42 has a cylindrical shape and is accommodated inside the stator 40. The inner peripheral surface of the core 41 is in contact with the outer peripheral surface of the coil body 42.

  FIG. 3 is a schematic view of the coil body 42 according to the first embodiment viewed along the central axis C. The coil body 42 includes a printed circuit board 1 which is wound a plurality of times and formed into a cylindrical shape. The printed circuit board 1 has a sheet shape before being formed into a cylindrical shape. The printed circuit board 1 has a wiring pattern to be described later. FIG. 3 shows an example in which the printed board 1 is wound three times and formed into a cylindrical shape. By winding the coil body 42 a plurality of times, the printed circuit board 1 overlaps in a radial direction of the printed circuit board 1 formed into a cylindrical shape. The coil body 42 may have a circular or polygonal cross-sectional shape when cut along a plane perpendicular to the central axis C. In the following description, the radial direction of the printed circuit board 1 formed in a cylindrical shape is also simply referred to as a radial direction.

  FIG. 4 is a plan development view of the printed circuit board 1 according to the first embodiment. The direction along the arrow Y shown in FIG. 4 is the direction along the central axis C, and the direction shown by the arrow X is the circumferential direction of the printed circuit board 1. In the following description, the circumferential direction of the printed circuit board 1 formed into a cylindrical shape is also simply referred to as a circumferential direction. Hereinafter, in the description of the printed circuit board 1 that has been developed in a plane, the terminology in the circumferential direction may be used for convenience. FIG. 4 shows the printed circuit board 1 that is formed into a cylindrical shape by performing two windings, that is, by winding twice, and is 1 when it is formed into a cylindrical shape from the circumferential end to the virtual line 53. Consists of layers.

  On the printed circuit board 1, a plurality of conductive wiring patterns 20 formed in a spiral shape are formed side by side along the circumferential direction. The wiring pattern 20 is composed of three phases of a U phase, a V phase, and a W phase. Specifically, the wiring pattern 20 is formed by sequentially arranging a U-phase first phase pattern 2, a V-phase second phase pattern 3, and a W-phase third phase pattern 4. Adjacent wiring patterns 20 are electrically insulated from each other. On the printed circuit board 1, three-phase wiring patterns 20, that is, a first phase pattern 2, a second phase pattern 3, and a third phase pattern 4 are formed as a set, and n sets of these are arranged side by side. Note that n is a natural number of 1 or more.

  In the printed circuit board 1 formed into a cylindrical shape, the first phase pattern 2, the second phase pattern 3, and the third phase pattern 4 are formed on each layer of the printed circuit board 1 so as to have the same number. Further, when viewed along the radial direction, the centers of the first phase patterns 2 formed in the respective layers coincide with each other. This coincides with the case where the center of the first phase pattern 2 formed on the inner peripheral layer and the center of the first phase pattern 2 formed on the outer peripheral layer are viewed along the radial direction. In other words. The centers of the second phase patterns 3 formed on each layer and the centers of the third phase patterns 4 formed on each layer also overlap when viewed along the radial direction. The wiring patterns 20 that overlap when viewed along the radial direction are electrically connected to each other at their ends. The wiring pattern 20 functions as a coil of the stator 40 by forming the printed circuit board 1 into a cylindrical shape.

  The printed circuit board 1 is formed with a terminal connection portion 7 protruding in the direction along the central axis C. The terminal connection portion 7 is provided with the end of the wiring pattern 20. As shown in FIG. 1, the terminal connection portion 7 protrudes in the direction along the central axis C even in a state where the printed circuit board 1 is formed in a cylindrical shape. By connecting a power line (not shown) to the end of the wiring pattern 20 provided in the protruding portion, power can be supplied to the wiring pattern 20. In addition, since the wiring patterns 20 formed in each layer are electrically connected to each other, if the terminal end of the wiring pattern 20 formed in any layer is provided in the terminal connection portion 7, the wiring patterns 20 are formed in all layers. Electric power can be supplied to the wiring pattern 20.

  Next, returning to FIG. 3, the range in which the wiring pattern 20 is formed will be described. In FIG. 3, a portion where the axial pattern 20 a (see also FIG. 4) extending along the central axis C is formed as the wiring pattern 20 in one wiring pattern 20 formed in a spiral shape. Therefore, the first phase pattern 2 actually connected by one line is shown divided in the circumferential direction in FIG. The same applies to the second phase pattern 3 and the third phase pattern 4.

  As shown in FIG. 3, the length L of the wiring pattern 20 along the circumferential direction is a wiring pattern formed on the outer peripheral layer than the length L of the wiring pattern 20 formed on the inner peripheral layer. The length L of 20 is longer. In other words, the length L of the wiring pattern 20 along the circumferential direction can be said to be the length between the outermost portions of the wiring pattern 20 along the circumferential direction when viewed along the central axis C. That is, the length L of the wiring pattern 20 is the circumferential length of the wiring pattern 20 formed in a spiral shape.

  The number of turns of the wiring pattern 20 formed in a spiral shape is larger or the same as the number of turns of the wiring pattern 20 formed in the outer peripheral layer. Note that the number of windings of the first phase pattern 2, which is the wiring pattern 20 formed in the same layer, the second phase pattern 3, and the third phase pattern 4 may be the same or different. Also good.

  In FIG. 3, the coil body 42 is formed on the printed circuit board 1 when the first phase pattern 2, the second phase pattern 3, and the third phase pattern 4 are formed on each layer of the coil body 42. The coil body 42 in the case where n, which is the number of sets of the first phase pattern 2, the second phase pattern 3, and the third phase pattern 4, is 1, is illustrated. Here, when the line connecting the center positions between the wiring patterns 20 is the radial center line 51, the angle θ1 formed by the radial center lines 51 is 120 °. In addition, the length L along the circumferential direction of the wiring pattern 20 is defined as a gap between the wiring pattern 20 and the radial center line 51, and the wiring pattern 20 is formed in a state where the printed circuit board 1 is formed into a cylindrical shape. When the radius of the layer formed is r, L = r × (2/3) π−d × 2, that is, L = (2/3) πr−2d.

  The size of the gap d is determined by the relationship between the insulation distance between the adjacent wiring patterns 20 or the width of the line forming the wiring pattern 20 and the line interval. In the present embodiment, as shown in FIG. 3, since the size of the gap d is constant between the inner peripheral layer and the outer peripheral layer, the length L of the wiring pattern 20 is changed from the inner peripheral layer to the outer peripheral side. Longer towards the layer.

  In addition, the axial pattern 20a (see also FIG. 4) extending along the central axis C among the one wiring pattern 20 formed in a spiral shape has a range in which the angle θ2 from the radial center line 51 is 45 °. It is formed. In other words, the axial pattern 20a is formed while avoiding a range where the angle θ3 from the pattern center line 52, which is the center line between the radial center lines 51, to both sides is 15 °.

  The axial pattern 20a formed within a range in which the angle θ3 from the pattern center line 52 to both sides is 15 ° has a small contribution to the generation of magnetic flux, and causes a loss due to a resistance component to increase. Therefore, it is desirable to form the axial pattern 20a while avoiding this range, but it does not deny that the axial pattern 20a is formed within a range where the angle θ3 is 15 °.

  Examples of the material of the printed circuit board 1 include a glass epoxy board in which a general epoxy material and a glass cloth are combined, but the material is not limited thereto. For example, a polyimide-based flexible substrate may be used.

  The method for forming the wiring pattern 20 on the printed circuit board 1 is not particularly limited. In a general method for forming the wiring pattern 20, a copper layer is formed on a glass epoxy substrate, and copper electroless plating and electroplating are performed. Thereafter, a resist is formed, and the copper layer is patterned using the resist as a mask to obtain a spiral wiring pattern 20. Further, a solder resist may be formed on the wiring pattern 20 to protect the wiring pattern 20 from dust, dust, and moisture and to ensure insulation.

  The wiring pattern 20 may be formed on both sides of the printed circuit board 1 or only on one side. When each of the first phase pattern 2, the second phase pattern 3, and the third phase pattern 4 is formed on both surfaces of the printed circuit board 1, it is necessary to form the wiring patterns 20 having different phases so as not to cross each other. When wiring patterns 20 of different phases intersect, a material that takes insulation into consideration may be placed between the wiring patterns 20. Further, when the U-phase, V-phase, and W-phase wiring patterns 20 are arranged, it is necessary to provide the neutral point 6.

  When the printed circuit board 1 is wound and formed into a cylindrical shape, an adhesive is applied to the entire surface or a part of the insulating layer surface that is one surface of the wiring pattern 20 of the printed circuit board 1 to provide an adhesive layer. Thereafter, the printed board 1 is wound and formed into a cylindrical shape. Thereafter, the cylindrical coil body 42 is formed by curing the adhesive by room temperature curing, heat curing, photocuring, or moisture curing. When a solder resist is formed on the wiring pattern 20, each layer of the printed circuit board 1 may be bonded with the solder resist to form an adhesive layer.

  Or after winding the printed circuit board 1 which provided the insulating layer on the wiring pattern 20, and shape | molding it in a cylinder shape, an adhesive agent is made to adhere to the edge part of the printed circuit board 1, and room temperature hardening, heat-curing, photocuring, or moisture The coil body 42 may be formed by curing the adhesive by curing. Examples of the adhesive used at this time include a solvent volatile adhesive or a solventless curable adhesive as long as it is a heat curable adhesive. Examples of the solvent volatile adhesive include vinyl acetate and nitrile rubber. If it is a solvent-free curable adhesive, an epoxy adhesive, an acrylic adhesive, or a silicone adhesive is exemplified. Examples of the ultraviolet curable adhesive include an epoxy adhesive and an acrylic adhesive. If it is a room temperature curable adhesive, a moisture curable adhesive or an anaerobic adhesive is exemplified. Examples of moisture-curing adhesives include cyanoacrylate adhesives and silicone rubber adhesives. If it is an anaerobic adhesive, an acrylate adhesive will be exemplified. These adhesives may be used alone or in combination.

  The rotor 50 is provided inside the stator 40, that is, inside the coil body 42 formed in a cylindrical shape, and is rotatable about the central axis C. The rotor 50 rotates about the central axis C by supplying power to the wiring pattern 20 that is a coil of the rotating machine 30 at a predetermined timing.

  According to the rotating machine 30 described above, the length L of the wiring pattern 20 formed on the outer peripheral layer is longer than the length L of the wiring pattern 20 formed on the inner peripheral layer. . When the length L of the wiring pattern 20 is made equal on the inner peripheral side and the outer peripheral side, the gap d between the wiring patterns 20 increases toward the outer peripheral side. On the other hand, in the rotating machine 30 according to the first embodiment, the length L of the wiring pattern 20 formed in the outer peripheral layer is increased, so that the gap between the wiring patterns 20 in the outer peripheral layer is enlarged. Can be suppressed. Thereby, more magnetic flux can be collected by the wiring pattern 20, and the output of the rotating machine 30 using the coil body 42 can be improved. In addition, by increasing the length L in the outer layer, the inductance can be increased and the current can be easily controlled.

  In the first embodiment, the gap d between the wiring patterns 20 is constant in the inner peripheral layer and the outer peripheral layer, but it is not necessarily constant. For example, even if the gap d between the wiring patterns 20 is not constant, if the length L of the wiring pattern 20 is increased toward the outer layer, the inductance can be reduced compared to the case where the length L is constant. The effect of increasing is obtained.

  In addition, the number of turns of the wiring pattern 20 formed in a spiral shape is larger or the same as the number of turns of the wiring pattern 20 formed on the outer peripheral layer. As a result, the output of the rotating machine 30 using the coil body 42 can be improved.

  FIG. 5 is a diagram illustrating a first modification of the printed circuit board 1 illustrated in FIG. 4. The printed circuit board 1 according to the first modification is provided with a mark 11 that is an alignment part that aligns a portion that becomes the inner peripheral layer and a portion that becomes the outer peripheral layer of the printed circuit board 1. The mark 11 was viewed along the radial direction by overlapping the mark 11 formed on the inner peripheral layer and the mark 11 formed on the outer peripheral layer when the printed circuit board 1 was wound in a cylindrical shape. In this case, the wiring patterns 20 are formed at positions where the centers thereof coincide with each other. When the mark 11 of the layer provided on the back side can be confirmed through the printed circuit board 1, the mark 11 can be overlapped to form a cylinder. In addition, the mark 11 does not need to be provided in all the layers, and the number may differ for every layer. The number of the marks 11 may be one for one layer or plural. The position where the mark 11 is provided may be inside or outside the wiring pattern 20 formed in a spiral shape.

  By providing the alignment portion, the positional accuracy of the wiring pattern 20 can be improved, and the magnetic flux distribution in the space can be approximated to a sine wave. Thereby, torque ripple can be reduced. A normal coil is formed by winding a winding around a tooth. Therefore, winding of the winding is performed in order from the inner diameter side. That is, since the winding arrangement is performed on the basis of the inner diameter, the position of the winding on the outer diameter side where a large amount of magnetic flux is collected varies depending on the stacking tolerance due to the winding, so that the motor characteristics are likely to vary. On the other hand, in the first embodiment, the wiring pattern 20 formed on the printed circuit board 1 can be formed with higher positional accuracy than the winding regardless of the inner diameter side or the outer diameter side. Variations in motor characteristics due to can be suppressed.

  In addition, the coil according to the first embodiment is not configured by winding the winding around the teeth, but is formed by forming the wiring pattern 20 on the printed circuit board 1, and thus the wiring pattern 20 on the inner diameter side is omitted. It is also possible to do. When the winding magnetic flux hardly interlinks with the inner diameter side wiring pattern 20, the inner diameter side wiring pattern 20 not only contributes to an increase in output, but may cause an increase in resistance loss. In such a case, the motor efficiency can be improved by omitting the wiring pattern 20 on the inner diameter side.

  The alignment portion is not limited to the mark 11 and may be a hole formed in the printed circuit board 1. Moreover, the unevenness | corrugation which is formed in the printed circuit board 1 and fits mutually when it winds in the cylinder shape may be an alignment part. When the alignment portion is a hole or an unevenness, the positional accuracy of the wiring pattern 20 can be improved even when the mark 11 of the layer provided on the back side through the printed board 1 cannot be confirmed.

  FIG. 6 is a diagram illustrating a second modification of the printed circuit board 1 illustrated in FIG. 4. The printed circuit board 1 according to the modified example 2 is formed with an external force adding portion 12 that is a protruding portion protruding in a direction along the central axis C, in addition to the terminal connecting portion 7. A wiring pattern 20 is not formed on the external force adding portion 12. For this reason, even if an external force is applied to the external force adding portion 12, there is little possibility of disconnecting the wiring pattern 20. Further, since the external force adding portion 12 protrudes in the direction along the central axis C with respect to the printed board 1, it is easy to apply an external force in the process of winding the printed board 1. For example, it is possible to apply a force by gripping the external force addition unit 12. Therefore, an external force necessary for winding the printed circuit board 1 can be easily applied through the external force applying portion 12, and the printed circuit board 1 can be easily formed into a more accurate shape. Moreover, the work of winding the printed circuit board 1 can be facilitated.

  The position of the external force adding portion 12 is not particularly limited, but it is desirable that the external force adding portion 12 be provided at an end portion along the circumferential direction at which winding starts. Further, the number of the external force adding portions 12 is not limited, but it is easy to apply a force to the printed circuit board 1 by providing the external force applying portions 12 at positions facing the printed circuit board 1 in the direction along the central axis C. The external force adding portion 12 may be removed after the coil body 42 is molded, or may be left as a part of the coil body 42 as it is.

  Moreover, you may provide both the alignment part shown in FIG. 5 and the external force addition part 12 shown in FIG.

  The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

  DESCRIPTION OF SYMBOLS 1 Printed circuit board, 2 1st phase pattern, 3 2nd phase pattern, 4 3rd phase pattern, 6 Neutral point, 7 Terminal connection part, 11 mark, 12 External force addition part, 20 Wiring pattern, 20a Axial direction pattern, 30 Rotating machine, 40 stator, 41 core, 42 coil body, 50 rotor, 51 radial center line, 52 pattern center line, 53 imaginary line.

Claims (9)

A printed circuit board formed into a cylindrical shape having a plurality of layers wound around a plurality of turns;
A plurality of spiral wiring patterns formed on the printed circuit board along the circumferential direction of the printed circuit board formed into a cylindrical shape, and
When viewed along the radial direction of the printed circuit board formed into a cylindrical shape, the wiring patterns formed in each layer of the plurality of layers overlap,
The wiring patterns formed in each of the plurality of layers are electrically connected,
The direction of the wiring pattern formed in a layer on the outer peripheral side of the wiring pattern in which is formed on the periphery of the layers out of the plurality of layers, the length along the circumferential direction is rather long,
The printed circuit board has a plurality of protrusions protruding in a direction along the central axis of the printed circuit board formed into a cylindrical shape,
The plurality of protrusions are formed in pairs at positions facing each other with the printed circuit board interposed therebetween, and are arranged side by side in the circumferential direction .   2. The number of turns of the wiring pattern formed on the outer peripheral layer of the plurality of layers is greater than the number of turns of the wiring pattern formed on the inner peripheral layer. Coil body.   The coil body according to claim 1 or 2, wherein the wiring pattern is electrically insulated from the wiring pattern adjacent along the circumferential direction.   The coil body according to any one of claims 1 to 3, wherein the printed circuit board has alignment portions that overlap with the plurality of layers when viewed in the radial direction. Before SL wiring pattern, a coil body according to claim 1, any one of claims 4, characterized in that is formed to avoid the protrusion. The pair of projecting portions among the plurality of projecting portions are provided at an end portion on the inner peripheral side that becomes the start of winding of the printed circuit board formed in a cylindrical shape. The coil body according to any one of 5. The coil body according to any one of claims 1 to 6 ,
A stator having a cylindrical shape surrounding an outer periphery of the coil body and having an inner peripheral surface in contact with the outer peripheral surface of the coil body. A stator according to claim 7 ;
And a rotor provided rotatably inside the stator. It is a manufacturing method of the coil object according to claim 1,
Applying an adhesive to the planar printed circuit board;
A step of winding the printed circuit board into a cylindrical shape;
And a step of curing the adhesive.

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