WO2024248010A1 - Coil substrate, coil substrate for motor, and motor - Google Patents

Abstract

Provided are a coil substrate capable of reducing the influence of wiring resistance and eddy current, a coil substrate for a motor, and a motor. A coil substrate according to an embodiment includes a resin substrate having a first surface and a second surface, and coil wiring formed on the first surface and the second surface of the resin substrate. The coil wiring is composed of a first conductor layer and an additional plating layer. The first conductor layer is composed of a metal foil layer, a chemical plating layer formed on the metal foil layer, and an electrolytic plating layer formed on the chemical plating layer. The additional plating layer covers an upper surface and a side surface of the first conductor layer. The cross-sectional shape of a side-surface part of the additional plating layer that covers the side surface of the first conductor layer does not follow the cross-sectional shape of the side surface of the first conductor layer.

Description

Coil substrate, coil substrate for motor, and motor

The technology disclosed in this specification relates to a coil substrate, a coil substrate for a motor, and a motor.

Patent Document 1 discloses a method for manufacturing a coil substrate. In this method, copper foil is provided on a flexible substrate, an electrolytic plating film is formed on a seed layer exposed from a plating resist pattern provided on the surface of the copper foil, the plating resist pattern is peeled off, and the seed layer and copper foil exposed from the electrolytic plating film are peeled off to form wiring.

JP 2020-181853 A

<Problems with Patent Document 1>
In the technology of Patent Document 1, after the plating resist pattern is peeled off, the seed layer and copper foil exposed from the electrolytic plating film are peeled off by etching. Therefore, it is difficult to control the width and thickness of the wiring during pattern formation within a predetermined range, and if the width and thickness of the wiring are smaller than the predetermined range, the wiring resistance may increase, and conversely, if the width and thickness of the wiring are larger than the predetermined range, the influence of eddy currents is considered to be large. It is considered difficult to stably reduce the influence of wiring resistance and eddy currents in the coil substrate formed by the technology of Patent Document 1.

The coil board of the present invention includes a resin substrate having a first surface and a second surface, and coil wiring formed on the first surface and the second surface of the resin substrate. The coil wiring is composed of a first conductor layer and an additional plating layer, the additional plating layer covers the upper surface and side surfaces of the first conductor layer, and the cross-sectional shape of the side surface portion of the additional plating layer that covers the side surface of the first conductor layer does not follow the cross-sectional shape of the side surface of the first conductor layer.

The coil board of the present invention includes a resin substrate having a first surface and a second surface, and coil wiring formed on the first surface and the second surface of the resin substrate. The coil wiring is made of a first conductor layer and an additional plating layer, the first conductor layer is made of a metal foil layer, a chemical plating layer formed on the metal foil layer, and an electrolytic plating layer formed on the chemical plating layer, the additional plating layer covers the top surface and side surfaces of the first conductor layer, and the cross-sectional shape of the side surface portion of the additional plating layer that covers the side surface of the first conductor layer does not follow the cross-sectional shape of the side surface of the first conductor layer.

In the coil substrate of the present invention, the distance between the cross-sectional shape of the side portion of the additional plating layer and the cross-sectional shape of the side portion of the first conductor layer is not constant in the height direction.

In the coil substrate of the present invention, the cross-sectional shape of the side surface of the additional plating layer does not have any portion parallel to the cross-sectional shape of the side surface of the first conductor layer.

The coil substrate of the present invention has a width of the coil wiring of 60 μm or more and 600 μm or less, and a thickness of 20 μm or more and 200 μm or less.

The coil substrate of the present invention has a width of the coil wiring of 100 μm or more and 300 μm or less, and a thickness of 20 μm or more and 200 μm or less.

The coil substrate of the present invention has a width of the coil wiring of 60 μm or more and 600 μm or less, and a thickness of 40 μm or more and 100 μm or less.

The coil substrate of the present invention has a width of the coil wiring of 100 μm or more and 300 μm or less, and a thickness of 40 μm or more and 100 μm or less.

In the coil substrate of the present invention, the thickness M2 of the portion of the additional plating layer that covers the upper surface of the first conductor layer and the thickness M1 of the first conductor layer have a relationship of 1.4M1 ≧ M2 > 1.0M1.

In the coil substrate of the present invention, the cross-sectional shape of the first conductor layer is substantially trapezoidal, having a lower base facing the resin substrate and an upper base opposite the lower base.

In the coil substrate of the present invention, the side surfaces of the first conductor layer have different inclination angles.

In the coil substrate of the present invention, the sidewall of the additional plating layer includes an inverted tapered portion in which the thickness decreases toward the resin substrate side.

The coil substrate of the present invention is a coil substrate for a motor that is formed by winding a coil substrate into a substantially cylindrical shape.

The coil substrate for motors of the present invention has a space factor of the coil wiring of 50% or more and 99% or less.

The coil substrate for motors of the present invention has a space factor of the coil wiring of 55% or more and 90% or less.

The coil substrate for motors of the present invention has a space factor of the coil wiring of 60% or more and 80% or less.

The motor coil substrate of the present invention has a cylindricity of the outer peripheral surface of the motor coil substrate that is greater than 0.0 mm and less than or equal to 0.3 mm.

The motor coil substrate of the present invention has a cylindricity of the outer peripheral surface of the motor coil substrate that is greater than 0.0 mm and less than or equal to 0.2 mm.

The motor coil substrate of the present invention has a space factor of the coil wiring of 50% or more and 99% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.3 mm.

The motor coil substrate of the present invention has a space factor of the coil wiring of 55% or more and 90% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.3 mm.

The motor coil substrate of the present invention has a space factor of the coil wiring of 60% or more and 80% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.3 mm.

The motor coil substrate of the present invention has a space factor of the coil wiring of 50% or more and 99% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.2 mm.

The motor coil substrate of the present invention has a space factor of the coil wiring of 55% or more and 90% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.2 mm.

The motor coil substrate of the present invention has a space factor of the coil wiring of 60% or more and 80% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate is greater than 0.0 mm and less than 0.2 mm.

The motor coil substrate of the present invention has an outer diameter of 50 mm or less.

The motor of the present invention is a motor formed by mounting one of the motor coil substrate and the magnet on the rotor and the other on the stator.

In an embodiment of the present invention, an additional plating layer is formed on the first conductor layer, which is made of a metal foil layer, a chemical plating layer, and an electrolytic plating layer, to cover the top and side surfaces of the first conductor layer. Therefore, the width and thickness of the coil wiring formed primarily by the first conductor layer can be complemented by the subsequent additional plating layer and adjusted to within a predetermined range. In particular, by ensuring that the shape of the side portion of the additional plating layer does not follow the shape of the side surface of the first conductor layer, it is possible to prevent the overall width of the coil wiring from becoming excessively larger than predetermined. The coil substrate of the embodiment can reduce the effects of wiring resistance and eddy currents. It also has the effect of improving the space factor of the coil.

FIG. 2 is a plan view showing a coil substrate according to the embodiment. 2 is a cross-sectional view taken along line II-II of FIG. 1. FIG. 1 is a perspective view illustrating a coil substrate for a motor using the coil substrate according to an embodiment of the present invention. 4 is a cross-sectional view showing a schematic view of the positions of each terminal when the motor coil substrate is viewed in the axial direction. FIG. FIG. 5 is an enlarged view of a portion VIII in FIG. 4 . 3 is a cross-sectional view showing a schematic diagram of a conductor layer that becomes a coil wiring provided on the coil substrate of the embodiment. FIG. 5A to 5C are cross-sectional views each showing a schematic diagram of a method for manufacturing a coil substrate according to an embodiment of the present invention. 5A to 5C are cross-sectional views each showing a schematic diagram of a method for manufacturing a coil substrate according to an embodiment of the present invention. 5A to 5C are cross-sectional views each showing a schematic diagram of a method for manufacturing a coil substrate according to an embodiment of the present invention. 5A to 5C are cross-sectional views each showing a schematic diagram of a method for manufacturing a coil substrate according to an embodiment of the present invention. 5A to 5C are cross-sectional views each showing a schematic diagram of a method for manufacturing a coil substrate according to an embodiment of the present invention. 5A to 5C are cross-sectional views each showing a schematic diagram of a method for manufacturing a coil substrate according to an embodiment of the present invention. 5A to 5C are cross-sectional views each showing a schematic diagram of a method for manufacturing a coil substrate according to an embodiment of the present invention. 1 is a cross-sectional view that illustrates a motor using a motor coil substrate according to an embodiment of the present invention.

<Embodiment>
Fig. 1 is a plan view showing a coil substrate 2 according to an embodiment of the present invention, and Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1.

As shown in FIG. 1, the coil substrate 2 has a flexible substrate 10, a U-phase coil 20U, a V-phase coil 20V, a W-phase coil 20W, a U-phase terminal 40U, a V-phase terminal 40V, a W-phase terminal 40W, a plurality of inter-coil connection wires 50U, 50V, 50W, a plurality of inter-phase connection wires 60U, 60V, and a return wire 70W.

The flexible substrate 10 is a resin substrate having a first surface 10F and a second surface 10B opposite to the first surface 10F. The flexible substrate 10 is formed using an insulating resin such as polyimide or polyamide. The flexible substrate 10 is flexible. The flexible substrate 10 is formed in a rectangular shape having four sides, a first side E1 to a fourth side E4. The first side E1 is a short side at one end of the longitudinal direction (the direction of the arrow LD in FIG. 1) of the flexible substrate 10. The second side E2 is a short side at the other end of the longitudinal direction. The first side E1 and the second side E2 are both short sides extending along an orthogonal direction (the direction of the arrow OD in FIG. 1) perpendicular to the longitudinal direction. The third side E3 and the fourth side E4 are both long sides extending along the longitudinal direction. As will be described in detail later, when the coil substrate 2 is wound into a cylindrical shape to form the motor coil substrate 550 (see FIG. 3 described later), the first surface 10F is disposed on the inner circumference side, and the second surface 10B is disposed on the outer circumference side. Alternatively, the first surface 10F may be disposed on the outer circumference side, and the second surface 10B may be disposed on the inner circumference side.

The U-phase terminal 40U, the V-phase terminal 40V, and the W-phase terminal 40W are all formed on the third side E3 of the flexible substrate 10. As shown in FIG. 1, the U-phase terminal 40U is connected to the starting end 20US of the U-phase coil 20U. At the same time, the U-phase terminal 40U is connected to the ending end 20WE of the W-phase coil 20W via the return line 70W. The V-phase terminal 40V is connected to the starting end 20VS of the V-phase coil 20V. At the same time, the V-phase terminal 40V is connected to the ending end 20UE of the U-phase coil 20U via the interphase connection line 60U. The W-phase terminal 40W is connected to the starting end 20WS of the W-phase coil 20W. At the same time, the W-phase terminal 40W is connected to the ending end 20VE of the V-phase coil 20V via the interphase connection line 60V.

The U-phase coil 20U, V-phase coil 20V, and W-phase coil 20W respectively constitute the U-phase, V-phase, and W-phase of the three-phase motor.

<U-phase coil>
1, U-phase coil 20U includes six coils 31U, 32U, 33U, 34U, 35U, and 36U. The six coils 31U to 36U are arranged in this order from a starting end 20US to a terminal end 20UE of U-phase coil 20U.

All six coils 31U to 36U are formed by forming a first wiring that constitutes half of one turn on the first surface 10F side, and a second wiring that constitutes the remaining half turn on the second surface 10B side, with adjacent turns being arranged in a shifted manner. The first wiring and second wiring are electrically connected through via conductors that penetrate the flexible substrate 10. The coil wiring of the U layer is formed by these first wiring and second wiring.

<V-phase coil>
1, V-phase coil 20V includes six coils 31V, 32V, 33V, 34V, 35V, and 36V. The six coils 31V to 36V are arranged in this order from a starting end 20VS of V-phase coil 20V toward a terminal end 20VE.

All six coils 31V to 36V are formed by forming a first wiring that constitutes half of one turn on the first surface 10F side, and a second wiring that constitutes the remaining half turn on the second surface 10B side, with adjacent turns being arranged with a shift. The first wiring and second wiring are electrically connected through via conductors that pass through the flexible substrate 10. The coil wiring of the V layer is formed by these first wiring and second wiring.

<W-phase coil>
1, W-phase coil 20W includes six coils 31W, 32W, 33W, 34W, 35W, and 36W. The six coils 31W to 36W are arranged in this order from a starting end 20WS of W-phase coil 20W toward a terminal end 20WE.

All six coils 31W to 36W are formed by forming a first wiring that constitutes half of one turn on the first surface 10F side, and a second wiring that constitutes the remaining half turn on the second surface 10B side, with adjacent turns being arranged in a shifted manner. The first wiring and second wiring are electrically connected through via conductors that penetrate the flexible substrate 10. The coil wiring of the W layer is formed by these first wiring and second wiring.

As shown in FIG. 1, in the embodiment, the wiring of each coil 20U, 20V, 20W is arranged in a hexagonal shape. In other examples, the wiring of each coil 20U, 20V, 20W may be arranged in any shape, such as a circle (a perfect circle, an ellipse), a triangle, a quadrangle (a square, a rectangle, a diamond), a pentagon, a polygon with seven or more sides, etc. In addition, the wiring arrangement shape of all coils is not limited to be the same, and the wiring arrangement shape may be different between coils. The number of turns of one coil wiring is not particularly limited, but may be one or more turns, and is preferably three to seven turns. The coil wiring is formed by arranging a half turn on the first surface, arranging a half turn on the second surface, and connecting them by a through hole. In addition, a half turn may be arranged on the second surface, and a half turn may be arranged on the first surface. In this case, a half turn refers to half of the coil wiring. Alternatively, a quarter turn may be placed on the first surface and a quarter turn on the second surface, connected by a through hole, for a total of half a turn on the first or second surface. Furthermore, the coil wiring may be placed on the first or second surface. In this case, the coil wiring on the first surface and the coil wiring on the second surface may overlap, may overlap partially, or may not overlap at all.

<Motor coil substrate>
FIG. 3 is a perspective view showing a motor coil board 550 using the coil board 2 of the embodiment. As shown in FIG. 3, the coil board 2 of the embodiment (FIGS. 1 and 2) is wound into a substantially cylindrical shape to form a motor coil board 550 for a motor. When the coil board 2 is wound into a cylindrical shape, it is wound multiple times around an axis (an axis extending parallel to the first side E1) extending in an orthogonal direction, starting from the first side E1 (FIG. 1). The number of times the coil board is wound is not particularly limited. When the coil board 2 is wound into a cylindrical shape, the first surface 10F of the flexible board 10 is disposed on the inner periphery side, and the second surface 10B is disposed on the outer periphery side. When the coil board 2 is wound into a cylindrical shape, the first surface 10F of the flexible board 10 may be disposed on the outer periphery side, and the second surface 10B may be disposed on the inner periphery side.

Figure 4 shows a schematic diagram of the position of each terminal when the motor coil substrate 550 is viewed along the axial direction. As shown in Figure 4, the U-phase terminal 40U, the V-phase terminal 40V, and the W-phase terminal 40W are arranged at intervals of approximately 120° in the circumferential direction. The U-phase terminal 40U and the W-phase terminal 40W are arranged on the inner circumferential surface. The V-phase terminal 40V is arranged on the outer circumferential surface. Note that the U-phase terminal 40U, the W-phase terminal 40W, and the V-phase terminal 40V may be arranged in any manner.

As shown in FIG. 4, the motor coil substrate 550 has an inner circumferential surface IC and an outer circumferential surface OC. The cylindricity of the outer circumferential surface OC is greater than 0.0 mm and less than 0.3 mm. If the cylindricity of the outer circumferential surface OC is greater than 0.0 mm and less than 0.3 mm, the motor coil substrate 550 will not roll evenly on a flat surface. By having the cylindricity of the outer circumferential surface OC greater than 0.0 mm and less than 0.3 mm, the adhesive strength with the yoke is increased when the motor is formed. A motor with stable performance can be obtained. In addition, it is preferable that the cylindricity of the outer circumferential surface OC of the motor coil substrate 550 is greater than 0.0 mm and less than 0.2 mm. By having the cylindricity of the outer circumferential surface OC greater than 0.0 mm and less than 0.2 mm, the adhesive strength with the yoke is increased when the motor is formed, and the motor can be stabilized. Therefore, even when it is operated as a motor, the motor coil substrate 550 does not shift in position, and a motor with stable performance can be obtained.

The cylindricity of the outer peripheral surface OC is measured using a V-block measurement method. That is, the motor coil substrate 550 is placed on a V-block, rotated once, and the difference in the direction perpendicular to the axis is measured at three different points, and the average value is calculated to measure the cylindricity of the outer peripheral surface OC.

Figure 5 is an enlarged view of part VIII in Figure 4, showing an example of a terminal configuration. As shown in Figure 5, conductor layers 100F, 100B of coils 20U, 20V, 20W are formed on first surface 10F and first surface 10F, and insulating layers 102F, 102B are formed on conductor layers 100F, 100B of coils 20U, 20V, 20W. In addition, inter-coil connection lines 50U, 50V, 50W, inter-phase connection lines 60U, 60V, and return line 70W are covered with insulating layers 102F, 102B. The insulating layers may be formed following the wiring, or may cover the circuit and fill the spaces between adjacent wiring with insulating layers. By forming the insulating layers 102F, 102B, the conductor layers 100F, 100B are not exposed, and there is no contact between the conductor layers 100F, 100B adjacent in the longitudinal direction of the flexible substrate 10, or between the conductor layers 100F, 100B adjacent in the radial direction in the cross section when the coil substrate 2 is wound, so insulation is maintained. The method of forming the insulating layers 102F, 102B is not particularly limited, but they can be formed by printing a liquid resin, electrolytic deposition of a resin, or pasting a coverlay. Examples of resins include insulating resins such as polyimide and epoxy resin. In FIG. 5, the insulating layers 102F, 102B are formed to follow the conductor layers 100F, 100B, but they may also be in a form in which they cover the upper surfaces of the conductor layers 100F, 100B and fill the gap between the conductor layers 100F, 100B. The thickness of the insulating layers 102F and 102B is not particularly limited, but it is preferable to form them to be about 1 μm or more and 30 μm or less. In FIG. 5, the conductor layers 100F and 100B are formed symmetrically with the flexible substrate 10 in between, but the conductor layers 100F and 100B may be partially overlapped with the flexible substrate 10 in between, or the conductor layers 100F and 100B may not overlap with the flexible substrate 10 in between.

At this time, the cross section of the motor coil substrate 550 is composed of the flexible substrate 10, the conductor layers which are the wiring of each phase, and the insulating layers which cover the conductor layers. At this time, the result of calculating the cross-sectional area of all the conductor layers in the cross-sectional area of the motor coil substrate 550 is the coil space factor. At this time, the coil space factor in the cross section of the motor coil substrate 550 is 50% or more and 99% or less. A high space factor of the coil conductor is ensured. Therefore, when a motor is formed using the motor coil substrate 550 of the embodiment, high torque is obtained. A motor with high performance is obtained. At this time, the coil space factor is calculated as follows: Space factor = (sum of cross-sectional areas of conductor parts / coil cross-sectional area) x 100.

The space factor of the coils 20U, 20V, and 20W combined in the cross section of the motor coil substrate 550 is 50% or more and 99% or less. By using the motor coil substrate 550 with a space factor of 50% or more and 99% or less, a high-torque motor can be obtained. Furthermore, when the motor coil substrate 550 of the embodiment is applied to a small motor, the torque can be improved and problems due to eddy currents and electrical resistance are also suppressed. As a result, a high-performance motor can be obtained. Note that a small motor in this specification is a motor with an outer diameter of 50 mm or less.

In addition, it is preferable that the coil space factor in the cross section of the motor coil substrate 550 is 55% or more and 90% or less. By using a motor coil substrate 550 with a coil space factor of 55% or more and 90% or less, a high-torque motor can be obtained. Furthermore, when the motor coil substrate 550 of the embodiment is applied to a small motor, the torque can be improved and problems due to eddy currents and electrical resistance are also suppressed. As a result, a high-performance motor can be obtained.

Moreover, it is more preferable that the coil space factor in the cross section of the motor coil substrate 550 is 60% or more and 80% or less. A high space factor of the coil conductor is ensured, and when wound cylindrically, it forms a specified cylindrical shape. Furthermore, even in small motors, a high space factor of the coil conductor is ensured, and when wound cylindrically, it forms a specified cylindrical shape, the torque can be improved, and problems with eddy currents and electrical resistance are suppressed. As a result, a high-performance motor is obtained.

When forming the motor coil substrate 550, the number of turns of the coil substrate 2 is arbitrary. The number of turns of the coil substrate 2 is preferably 2 to 10 turns. By setting the number of turns to 2 to 10 turns, the cylindricity of the outer peripheral surface OC of the formed motor coil substrate 550 is greater than 0.0 mm and less than 0.3 mm, as described above. As a result, the deterioration of motor performance can be suppressed.

The coil space factor in the cross section of the motor coil substrate 550 is 50% or more and 99% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and 0.3 mm or less. In the motor coil substrate 550 of the embodiment of the present invention, when a motor is formed using the motor coil substrate 550 having a coil space factor of 50% or more and 99% or less, and a cylindricity of the outer peripheral surface OC of greater than 0.0 mm and 0.3 mm or less, the adhesive strength with the yoke is increased during motor formation, and high torque is obtained. A high-performance motor is obtained. Furthermore, when the motor coil substrate 550 of the embodiment is applied to a small motor, the torque can be improved and defects due to eddy currents and electrical resistance are also suppressed. As a result, a high-performance motor is obtained.

In addition, the coil space factor in the cross section of the motor coil substrate 550 is 55% or more and 90% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and 0.3 mm or less. In the motor coil substrate 550 of the embodiment of the present invention, when a motor is formed using the motor coil substrate 550 in which the coil space factor is 55% or more and 90% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and 0.3 mm or less, the adhesive strength with the yoke is increased when the motor is formed, high torque is obtained, and defects due to eddy currents and electrical resistance are suppressed. As a result, a high-performance motor is obtained.

Furthermore, the coil space factor in the cross section of the motor coil substrate 550 is 60% or more and 80% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and 0.3 mm or less. In the motor coil substrate 550 of the embodiment of the present invention, when a motor is formed using the motor coil substrate 550 in which the coil space factor is 60% or more and 80% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and 0.3 mm or less, the adhesive strength with the yoke is increased when the motor is formed, high torque is obtained, and defects due to eddy currents and electrical resistance are suppressed. As a result, a high-performance motor is obtained.

The coil space factor in the cross section of the motor coil substrate 550 is 50% or more and 99% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and less than 0.2 mm. In the motor coil substrate 550 of the embodiment of the present invention, when a motor is formed using the motor coil substrate 550 having a coil space factor of 50% or more and 99% or less, and a cylindricity of the outer peripheral surface OC of greater than 0.0 mm and less than 0.2 mm, the adhesive strength with the yoke is increased when the motor is formed, high torque is obtained, and defects due to eddy currents and electrical resistance are suppressed. As a result, a high-performance motor is obtained.

In addition, the coil space factor in the cross section of the motor coil substrate 550 is 55% or more and 90% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and 0.2 mm or less. In the motor coil substrate 550 of the embodiment of the present invention, when a motor is formed using the motor coil substrate 550 in which the coil space factor is 55% or more and 90% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and 0.2 mm or less, the adhesive strength with the yoke is increased when the motor is formed, high torque is obtained, and defects due to eddy currents and electrical resistance are suppressed. As a result, a high-performance motor is obtained.

Furthermore, the coil space factor in the cross section of the motor coil substrate 550 is 60% or more and 80% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and 0.2 mm or less. In the motor coil substrate 550 of the embodiment of the present invention, when a motor is formed using the motor coil substrate 550 in which the coil space factor is 60% or more and 80% or less, and the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and 0.2 mm or less, the adhesive strength with the yoke is increased when the motor is formed, high torque is obtained, and defects due to eddy currents and electrical resistance are suppressed. As a result, a high-performance motor is obtained.

The motor coil substrate 550 of the embodiment is used in a slotless motor. In another example, the motor coil substrate 550 may be used in a motor other than a slotless motor.

The diameter of the outer peripheral surface OC (outer diameter of the cross section) of the motor coil substrate 550 is 50 mm or less. The diameter of the outer peripheral surface OC (outer diameter of the cross section) of the motor coil substrate 550 is preferably 30 mm or less. By forming a small motor using a motor coil substrate 550 with a diameter of 50 mm or less, it is possible to effectively suppress the deterioration of motor performance. The diameter of the outer peripheral surface OC of the motor coil substrate 550 is measured with a vernier caliper. In the embodiment shown in FIG. 1, the coil occupancy rate in the cross-sectional area of the motor coil substrate 550 is 70%. The ratio of wiring to the total weight of the motor coil substrate 550 is 93%. The cylindricity of the outer peripheral surface OC is 0.1 mm. The diameter of the outer peripheral surface OC (outer diameter of the cross section) of the motor coil substrate 550 is 16 mm.

<Detailed structure of coil wiring>
Next, the structure of the conductor layers 100F, 100B forming the coil wiring will be described. Fig. 6 is a schematic cross-sectional view showing an example of the cross-sectional structure of the conductor layer 100F or 100B (hereinafter, when there is no need to distinguish between them, they will simply be referred to as "conductor layer 100"). As shown in Fig. 6, the conductor layer 100 is composed of a first conductor layer 110 formed on the first surface 10F or the second surface 10B of the flexible substrate 10, and a second conductor layer 150 (additional plating layer).

The first conductor layer 110 consists of a metal foil layer 120, a chemical plating layer 130 formed on the metal foil layer 120, and an electrolytic plating layer 140 formed on the chemical plating layer 130.

The metal foil layer 120 contains Cu, Ni, Al, etc., and is formed by attaching it to the flexible substrate 10. It is preferable to use a metal foil layer 120 that is mainly composed of Cu, since it is easy to form wiring and has excellent electrical properties. A second boundary surface 125 is formed at the boundary between the metal foil layer 120 and the chemical plating layer 130. The second boundary surface 125 is located on the upper surface of the metal foil layer 120. A first boundary surface 115, which is the boundary between the metal foil layer 120 and the flexible substrate 10, is located on the lower surface of the metal foil layer 120. The first boundary surface 115 is the same as the first surface 10F or the second surface 10B. The first boundary surface 115 is the surface facing the flexible substrate 10. The cross-sectional shape of the metal foil layer 120 is approximately a trapezoid with the first boundary surface 115 as the lower base and the second boundary surface 125 as the upper base. The lower base of the metal foil layer 120 has a width W1. The sides 122, 122 of the metal foil layer 120 are inclined with respect to the illustrated up-down direction perpendicular to the first surface 10F or the second surface 10B of the flexible substrate 10. The metal foil layer 120 has a thickness t1. t1 = 10 to 50 μm.

The chemical plating layer 130 is formed by chemical plating containing Cu, Ni, etc. It is preferable to use a chemical plating layer 130 mainly composed of Cu, since this makes it easier to form wiring. A third boundary surface 135 is formed at the boundary between the chemical plating layer 130 and the electrolytic plating layer 140. The third boundary surface 135 is located on the upper surface of the chemical plating layer 130. The second boundary surface 125 is located on the lower surface of the chemical plating layer 130. The chemical plating layer 130 has side surfaces 132, 132. The chemical plating layer 130 has a thickness t2. t2 = 1 to 5 μm.

The electrolytic plating layer 140 is formed by electrolytic plating containing Cu and Ni. It is preferable to use electrolytic plating containing Cu as the main component because it is easy to form wiring and has excellent electrical properties. The electrolytic plating layer 140 has an upper surface 145. The third boundary surface 135 is located on the lower surface of the electrolytic plating layer 140. Although not clearly shown in the figure, the cross-sectional shape of the electrolytic plating layer 140 is approximately trapezoidal with the third boundary surface 135 as the lower base and the upper surface 145 as the upper base. The side surfaces 142, 142 of the electrolytic plating layer 140 are inclined with respect to the illustrated up-down direction perpendicular to the first surface 10F or the second surface 10B of the flexible substrate 10. The electrolytic plating layer 140 has a thickness t3. t3 = 10 to 50 [μm]. The inclination of the side surface 142 of the electrolytic plating layer 140 is steeper than the inclination of the side surface 122 of the metal foil layer 120.

Due to the shapes of the metal foil layer 120, the chemical plating layer 130, and the electrolytic plating layer 140 as described above, the cross-sectional shape of the first conductor layer 110 is approximately a trapezoid having a lower base (first boundary surface 115) facing the flexible substrate 10 and an upper base (upper surface 145) opposite the lower base. The first conductor layer 110 has an overall thickness t1 + t2 + t3. t1 + t2 + t3 ≧ 15 [μm]. The first conductor layer 110 has a width (width of the lower base of the metal foil layer 120) W1. W1 ≧ 55 [μm]. The inclination of the side surface 122 of the metal foil layer 120 in the first conductor layer 110 is gentler than the inclination of the side surface 142 of the electrolytic plating layer 140. In addition, the inner angle of the side surface 122 of the metal foil layer 120 is smaller than the inner angle of the electrolytic plating layer 140. Since the side of the first conductor layer 110 has different inclination angles, when the coil substrate 2 is wound, contact between adjacent conductor layers 100 is suppressed, and the coil substrate 2 is easy to wind. As a result, a predetermined cylindrical shape is formed, and rewinding is suppressed. In other words, the cross-sectional shape of the first conductor layer 110 may have side surfaces with different inclinations. Also, the side surfaces of the approximately trapezoid may have side surfaces with different inclinations. Since the cross-sectional shape of the first conductor layer 110 of the coil wiring is a trapezoidal shape having side surfaces with different inclination angles, even if additional plating is formed and the thickness direction is made thicker to increase the space factor of the coil, the coil wiring is suppressed from contacting adjacent wiring even in the motor coil substrate obtained by winding the coil substrate in an approximately cylindrical shape, and the cross-sectional shape of the motor coil substrate is also approximately circular. Note that the motor coil substrate obtained by winding the coil substrate in an approximately cylindrical shape (cylindrical shape) is synonymous with the motor coil substrate obtained by forming the coil substrate in an approximately cylindrical shape (cylindrical shape).

The cross-sectional shapes of the metal foil layer 120 and the electrolytic plating layer 140 are not limited to trapezoidal, and may be other quadrangular shapes such as square or rectangle. The cross-sectional shapes of the metal foil layer 120, the chemical plating layer 130, and the electrolytic plating layer 140 may be the same (e.g., trapezoidal) or may be different from each other.

The second conductor layer 150 is formed by electrolytic plating containing Cu and Ni. It is preferable to use a material containing Cu as the main component of the second conductor layer 150 because it is easy to form wiring and has excellent electrical properties. The second conductor layer 150 covers the upper surface and side surfaces of the first conductor layer 110. The upper surface of the first conductor layer 110 is the upper surface 145 of the electrolytic plating layer 140. The side surfaces of the first conductor layer 110 are the metal foil layer 120, the chemical plating layer 130, and the side surfaces 122, 132, and 142 of the electrolytic plating layer. It is also possible for there to be a recess in part of the side surface. The thickness of the second conductor layer 150 is 5 μm or more. The thickness tA of the portion of the second conductor layer 150 covering the upper surface of the first conductor layer 110 is greater than the thickness t1 + t2 + t3 of the first conductor layer 110. In other words, the thickness of the portion of the second conductor layer (additional plating layer) 150 that covers the upper surface of the first conductor layer 110 is greater than the thickness of the first conductor layer 110. The thickness tA is the distance from the upper surface 155 of the second conductor layer 150 to the upper surface 145 of the electrolytic plating layer 140.

The cross-sectional shape of the side portion of the second conductor layer 150 that covers the side of the first conductor layer 110 does not follow the cross-sectional shape of the side of the first conductor layer 110. Specifically, as shown in the enlarged view in FIG. 6, the cross-sectional shape of the side wall 152 of the second conductor layer 150 does not follow the cross-sectional shapes of the side surfaces 122, 132, and 142 of the metal foil layer 120, the chemical plating layer 130, and the electrolytic plating layer. The cross-sectional shape of the side wall 152 of the second conductor layer 150 does not have any part that is parallel to the cross-sectional shapes of the side surfaces 122, 132, and 142 of the metal foil layer 120, the chemical plating layer 130, and the electrolytic plating layer.

The distance between the cross-sectional shape of the sidewall 152 of the second conductor layer 150 and the cross-sectional shapes of the side surfaces 122, 132, and 142 of the metal foil layer 120, the chemical plating layer 130, and the electrolytic plating layer is not constant in the height direction. That is, as shown in the enlarged view of FIG. 6, the distance tB from the first conductor layer 110 to the outer surface of the second conductor layer 150 is not constant from top to bottom as shown in the figure, such as tB1 → tB2 → tB3 → tB4. In particular, the sidewall 152 of the second conductor layer 150 includes an inverted taper portion 152A that becomes thinner as it approaches the flexible substrate 10. In the inverted taper portion 152A, the distance tB from the first conductor layer 110 to the outer surface of the second conductor layer 150 becomes smaller as it approaches the flexible substrate 10.

The relationship between the thickness tA of the second conductor layer 150 and the distance tB to the outer surface of the second conductor layer 150 is 1.0≦tA/tB≦1.4. In the second conductor layer 150, 1.0≦tA/tB≦1.4 increases the space factor of the coil, making it easier to wind the coil substrate 2 when it is wound. In other words, the cylindricity of the motor coil substrate 550 can be within a predetermined range while keeping the space factor of the coil at a predetermined ratio. In addition, the relationship between the thickness tA of the second conductor layer 150 and the distance tB to the outer surface of the second conductor layer 150 is preferably 1.0≦tA/tB≦1.2. In the second conductor layer 150, 1.0≦tA/tB≦1.2 increases the space factor of the coil, making it easier to wind the coil substrate 2 when it is wound, and reducing the need for rewinding.

The second conductor layer 150 has an overall thickness t4. The second conductor layer 150 has a width W. The second conductor layer 150 has an inverted tapered portion 152A, which prevents contact with adjacent conductor circuits when the coil substrate 2 is wound. This prevents short circuits.

Due to the shapes of the first conductor layer 110 and the second conductor layer 150, the conductor layer 100 as a whole has a thickness t4 (=thickness of the second conductor layer 150). 20 [μm] ≦ t4 ≦ 200 [μm]. Preferably, 40 [μm] ≦ t4 ≦ 100 [μm]. The conductor layer 100 as a whole has a width W (width of the second conductor layer 150). 60 [μm] ≦ W ≦ 600 [μm]. Preferably, 100 [μm] ≦ W ≦ 300 [μm]. There is a distance (gap) G between adjacent conductor layers 100. 10 [μm] ≦ G ≦ 50 [μm].

The width W of the entire conductor layer 100 is 60 μm≦W≦600 μm, and the thickness t4 is 20 μm≦t4≦200 μm. By keeping the width W and thickness t4 of the entire conductor layer 100 within a specified range, the effects of wiring resistance and eddy currents can be stably reduced. This also has the effect of improving the space factor of the coil.

The width W of the entire conductor layer 100 is 60 μm≦W≦600 μm, and the thickness t4 is 40 μm≦t4≦100 μm. By keeping the width W and thickness t4 of the entire conductor layer 100 within a specified range, the effects of wiring resistance and eddy currents can be stably reduced. This also has the effect of improving the space factor of the coil.

The width W of the entire conductor layer 100 is 100 [μm] ≦ W ≦ 300 [μm], and the thickness t4 is 20 [μm] ≦ t4 ≦ 200 [μm]. By setting the width W and thickness t4 of the entire conductor layer 100 within a specified range, the influence of wiring resistance and eddy currents can be stably reduced. This also has the effect of improving the space factor of the coil.

The width W of the entire conductor layer 100 is 100 [μm] ≦ W ≦ 300 [μm], and the thickness t4 is 40 [μm] ≦ t4 ≦ 100 [μm]. By setting the width W and thickness t4 of the entire conductor layer 100 within a specified range, the influence of wiring resistance and eddy currents can be stably reduced. This also has the effect of improving the space factor of the coil.

<Method of Manufacturing Coil Substrate>
The coil substrate 2 of the embodiment is manufactured by any method. For example, the coil substrate 2 is formed by a tenting method using a flexible substrate 10 having a metal foil as a starting material. An example of the manufacturing process will be described below with reference to Figures 7A to 7G. Figures 7A to 7G are cross-sectional views that typically show a method of manufacturing the coil substrate 2 of the embodiment.

As shown in FIG. 7A, a flexible substrate 10 is prepared, with a metal foil layer 120 formed on a first surface 10F and a second surface 10B.

As shown in FIG. 7B, a through hole 10a is formed through the flexible substrate 10 using a drill or a laser. Note that a non-through hole remaining in the metal foil layer 120 on one side may be formed instead of the through hole 10a.

As shown in FIG. 7C, a chemical plating layer 130 is formed on the surface of the metal foil layer 120 and within the through-holes 10a of the flexible substrate 10 by chemical plating mainly composed of Cu.

As shown in FIG. 7D, the chemical plating layer 130 is used as a seed layer to form an electrolytic plating layer 140 on the surface of the chemical plating layer 130 by electrolytic plating, the main component of which is Cu.

As shown in FIG. 7E, a plating resist pattern 210 is formed on the electrolytic plating layer 140.

As shown in FIG. 7F, the electrolytic plating layer 140, the chemical plating layer 130, and the metal foil layer 120 exposed from the plating resist pattern 210 are removed by etching. The plating resist pattern 210 is then peeled off to complete the wiring pattern.

As shown in FIG. 7G, a second conductor layer 150 is formed on the entire exposed surface of the wiring pattern by electrolytic plating using Cu as the main component, completing the conductor layer 100.

<Motor>
8 is a cross-sectional view that shows a motor 600 that uses the motor coil substrate 550 (FIGS. 3 to 5) of the embodiment. The motor 600 is formed by arranging the motor coil substrate 550 inside a yoke 560, and arranging a rotating shaft 580 and a magnet 570 fixed to the rotating shaft 580 inside the motor coil substrate 550. The motor 600 of the embodiment is a slotless motor. The magnet 570 and the rotating shaft 580 form a rotor 610, and the motor coil substrate 550 and the yoke 560 form a stator 620.

The motor coil substrate 550 is disposed inside the cylindrical yoke 560. The outer peripheral surface OC of the motor coil substrate 550 and the inner peripheral surface 560a of the yoke 560 are fixed by adhesive. The inner peripheral surface IC of the motor coil substrate 550 and the outer peripheral surface 570a of the magnet 570 are disposed so as to face each other in the radial direction with a predetermined gap therebetween.

In the above embodiment, the magnet 570 is provided on the rotor 610, and the motor coil board 550 is provided on the stator 620, but this is not limited to the above. The magnet 570 may be provided on the stator, and the motor coil board 550 may be provided on the rotor.

Effects of the embodiment
As described above, the configurations of the coil board 2 (FIGS. 1-2), the motor coil board 550 (FIGS. 3-5), and the motor 600 (FIG. 8) of the embodiment have been described. As described above, in the coil board 2 of the embodiment, the second conductor layer 150 is formed to cover the upper surface and side surface of the first conductor layer 110, which is composed of the metal foil layer 120, the chemical plating layer 130, and the electrolytic plating layer 140. Therefore, the width and thickness of the coil wiring formed primarily by the first conductor layer 110 can be complemented by the second conductor layer 150 thereafter, and adjusted to a desired size. In particular, by making the cross-sectional shape of the side surface portion of the second conductor layer 150 not follow the cross-sectional shape of the side surface portion of the first conductor layer 110, it is possible to prevent the width W of the entire conductor layer 100 from becoming excessively larger than a predetermined value. In the coil board 2 of the embodiment, it is possible to reduce the influence of wiring resistance and eddy current, and also to improve the space factor of the coil. Furthermore, when the coil substrate 2 is wound, contact between adjacent conductor layers is suppressed, and the coil substrate 2 is easily wound into a predetermined cylindrical shape, so that the need for rewinding is suppressed.

In the coil board 2 of the embodiment, the distance between the cross-sectional shape of the side wall 152 of the second conductor layer 150 and the cross-sectional shapes of the side surfaces 122, 132, 142 of the metal foil layer 120, the chemical plating layer 130, and the electrolytic plating layer is not constant in the height direction. A specific configuration can be reliably realized in which the cross-sectional shape of the side surface portion of the second conductor layer 150 does not follow the cross-sectional shape of the side surface portion of the first conductor layer 110.

In the coil substrate 2 of the embodiment, the cross-sectional shape of the side wall 152 of the second conductor layer 150 does not have any parts parallel to the cross-sectional shapes of the side surfaces 122, 132, 142 of the metal foil layer 120, the chemical plating layer 130, and the electrolytic plating layer. A specific configuration can be reliably realized in which the cross-sectional shape of the side surface portion of the second conductor layer 150 does not follow the cross-sectional shape of the side surface portion of the first conductor layer 110.

In the coil substrate 2, if the width of the coil wiring is less than 60 μm and the thickness is less than 20 μm, the influence of the wiring resistance becomes large. In the coil substrate 2 of the embodiment, the width W of the conductor layer 100 is set to 60 μm or more and the thickness t4 is set to 20 μm or more, thereby reliably reducing the influence of the wiring resistance. If the width of the coil wiring exceeds 600 μm and the thickness exceeds 200 μm, the influence of eddy currents becomes large. By setting the width W of the conductor layer 100 to 600 μm or less and the thickness t4 to 200 μm or less, the influence of eddy currents can be reliably reduced.

In the coil substrate 2 of the embodiment, the thickness M2 (= tA) of the portion of the second conductor layer 150 covering the upper surface of the first conductor layer 110 and the thickness M1 (= t1 + t2 + t3) of the first conductor layer 110 satisfy the relationship 1.4M1 ≧ M2 > 1.0M1. By largely compensating for the thickness of the upper portion of the first conductor layer 110 with the thickness of the second conductor layer 150, it is possible to prevent the thickness of the entire conductor layer 100 from becoming smaller than the specified thickness.

In the coil substrate 2 of the embodiment, the sidewall 152 of the second conductor layer 150 includes an inverted tapered portion 152A that is thinner toward the flexible substrate 10 side. The thickness tB of the second conductor layer 150 on the flexible substrate 10 side is smaller than the thickness on the top surface (top surface 145 of the electrolytic plating layer 140) side of the first conductor layer 110. This makes it possible to prevent the overall width W of the conductor layer 100 from becoming larger than a predetermined value.

In this embodiment, the motor coil substrate 550 is bonded to the inner peripheral surface 560a of the yoke 560 disposed around the magnet 570 to form the motor 600. In this embodiment, the cylindricity of the outer peripheral surface OC of the motor coil substrate 550 is greater than 0.0 mm and is equal to or less than 0.3 mm. Therefore, compared to when the cylindricity is 0.0 mm, the outer peripheral surface OC of the motor coil substrate 550 and the inner peripheral surface 560a of the yoke 560 in the bonded state are less likely to slip, and the adhesive strength is high.

In this embodiment, a small motor 600 is formed using a motor coil substrate 550 with a diameter of 50 mm or less, which effectively prevents deterioration of motor performance. The diameter of the outer periphery of the motor coil substrate 550 is measured with a vernier caliper.

In the above, the coil substrate 2 is wound into a cylindrical shape to form the motor coil substrate 550, but this is not limited to the above. The configuration having the conductor layer 100 shown in FIG. 6 etc. can also be applied to a coil substrate that is used in a substantially flat shape without being wound into a cylindrical shape.

2: Coil substrate 10: Flexible substrate 10B: Second surface 10F: First surface 100: Conductive layer 110: First conductor layer 115: First boundary surface 120: Metal foil layer 122: Side surface 125 of metal foil layer: Second boundary surface 130: Chemical plating layer 132: Side surface 135 of chemical plating layer: Third boundary surface 140: Electrolytic plating layer 142: Side surface 145 of electrolytic plating layer: Top surface 150 of electrolytic plating layer: Second conductor layer 152: Side of second conductor layer Wall 152A: Inverted tapered portion 550: Motor coil substrate 570: Magnet 600: Motor 610: Rotor 620: Stator OC: Outer surface of motor coil substrate tA: Thickness of portion of second conductor layer covering first conductor layer tB: Distance from first conductor layer to outer surface of second conductor layer t1: Thickness of metal foil layer t2: Thickness of chemical plating layer t3: Thickness of electrolytic plating layer W: Width of second conductor layer W1: Width of bottom of metal foil layer

Claims (26)

A coil substrate including a resin substrate having a first surface and a second surface, and coil wiring formed on the first surface and the second surface of the resin substrate,
The coil wiring is made of a first conductor layer and an additional plating layer,
The additional plating layer covers an upper surface and a side surface of the first conductor layer,
The cross-sectional shape of a side surface portion of the additional plating layer that covers the side surface of the first conductor layer does not follow the cross-sectional shape of the side surface of the first conductor layer. The coil substrate of claim 1,
The first conductor layer is made of a metal foil layer, a chemically plated layer formed on the metal foil layer, and an electrolytically plated layer formed on the chemically plated layer. The coil substrate of claim 1, in which the distance between the cross-sectional shape of the side portion of the additional plating layer and the cross-sectional shape of the side portion of the first conductor layer is not constant in the height direction. The coil substrate of claim 1, wherein the cross-sectional shape of the side surface of the additional plating layer does not have any portion parallel to the cross-sectional shape of the side surface of the first conductor layer. The coil substrate of claim 1, wherein the width of the coil wiring is 60 μm or more and 600 μm or less, and the thickness is 20 μm or more and 200 μm or less. The coil substrate of claim 1, wherein the width of the coil wiring is 100 μm or more and 300 μm or less, and the thickness is 20 μm or more and 200 μm or less. The coil substrate of claim 1, wherein the width of the coil wiring is 60 μm or more and 600 μm or less, and the thickness is 40 μm or more and 100 μm or less. The coil substrate of claim 1, wherein the width of the coil wiring is 100 μm or more and 300 μm or less, and the thickness is 40 μm or more and 100 μm or less. The coil substrate of claim 1, wherein the thickness M2 of the portion of the additional plating layer that covers the upper surface of the first conductor layer and the thickness M1 of the first conductor layer have a relationship of 1.4M1 ≧ M2 > 1.0M1. The coil substrate of claim 1, wherein the cross-sectional shape of the first conductor layer is substantially trapezoidal, having a lower base facing the resin substrate and an upper base opposite the lower base. The coil substrate of claim 1, wherein the side surfaces of the first conductor layer have different inclination angles. The coil substrate of claim 1, wherein the sidewall of the additional plating layer includes an inverted tapered portion that becomes thinner toward the resin substrate. A coil substrate for a motor formed by winding the coil substrate of claim 1 into a substantially cylindrical shape. The motor coil substrate of claim 13, wherein the space factor of the coil wiring is 50% or more and 99% or less. The motor coil substrate of claim 13, wherein the space factor of the coil wiring is 55% or more and 90% or less. The motor coil substrate of claim 13, wherein the space factor of the coil wiring is 60% or more and 80% or less. The motor coil substrate of claim 13, wherein the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than or equal to 0.3 mm. The motor coil substrate of claim 13, wherein the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than or equal to 0.2 mm. The motor coil substrate of claim 13, wherein the space factor of the coil wiring is 50% or more and 99% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.3 mm. The motor coil substrate of claim 13, wherein the space factor of the coil wiring is 55% or more and 90% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.3 mm. The motor coil substrate of claim 13, wherein the space factor of the coil wiring is 60% or more and 80% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.3 mm. The motor coil substrate of claim 13, wherein the space factor of the coil wiring is 50% or more and 99% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.2 mm. The motor coil substrate of claim 13, wherein the space factor of the coil wiring is 55% or more and 90% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.2 mm. The motor coil substrate of claim 13, wherein the space factor of the coil wiring is 60% or more and 80% or less, and the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and less than 0.2 mm. The motor coil substrate of claim 13, wherein the outer diameter of the motor coil substrate is 50 mm or less. A motor formed by providing one of the motor coil board and the magnet according to claim 13 on a rotor and providing the other on a stator.

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