Motor coil board and motor

Abstract

To provide a coil substrate with which a motor exhibiting stable performance is obtained, a coil substrate for the motor formed using the coil substrate, and the motor formed using the coil substrate for the motor.SOLUTION: A coil substrate according to an embodiment comprises a flexible substrate provided with a first face and a second face on an opposite side of the first face, and a plurality of coils formed from wiring provided on the first face and the second face. The coil substrate is possible to be cylindrically formed with a first end in a longitudinal direction of the flexible substrate as a starting point by being wound in a circumferential direction with an axis extending in an orthogonal direction that is orthogonal to the longitudinal direction as a center. The flexible substrate comprises a first area near the first end, and a second area next to the first area. A width of first wiring formed in the first area out of the wiring is wider than a width of second wiring formed in the second area.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The technology disclosed by this specification relates to a coil substrate, a motor coil substrate formed using the coil substrate, and a motor formed using the motor coil substrate.

Background Art

[0002] Patent Document 1 discloses a coil substrate having a flexible substrate and spiral wiring formed on both sides of the flexible substrate. A motor coil substrate is formed by winding the coil substrate cylindrically. The formed motor coil substrate is disposed inside a cylindrical yoke, and a motor is formed by disposing a rotating shaft and a magnet inside the motor coil substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] [Problems of Patent Document 1] In the technology of Patent Document 1, it is considered that the coil substrate is wound in the circumferential direction around an axis extending in the orthogonal direction (width direction) orthogonal to the longitudinal direction, starting from the side at one end in the longitudinal direction of the flexible substrate. Among the wirings, the width of the portion formed in the vicinity of one end side in the longitudinal direction of the flexible substrate (i.e., the start end side in the winding direction) is considered to be wider than the width of the portion formed in the vicinity of the other end side in the longitudinal direction of the flexible substrate (i.e., the end end side in the winding direction). That is, it is considered that the width of the wiring located on the outermost circumference when the coil substrate is wound in the circumferential direction is wider than the width of the wiring located on the inner circumference.

[0005] When a coil substrate is wound in the circumferential direction, the gaps between the wires are susceptible to force and bending because there are no wires in those gaps. In the technology described in Patent Document 1, the width of the outermost wire is wider than the width of the innermost wire. It is thought that the gaps between the outermost wires overlap with the gaps between the innermost wires. Therefore, it is thought that the motor coil substrate can be formed in a polygonal cylindrical shape with a polygonal cross-section rather than a cylindrical shape with a circular cross-section.

[0006] If the motor coil substrate is polygonal cylindrical, it may interfere with the magnets placed inside during motor assembly. Furthermore, an increase in the air gap between the motor coil substrate and the yoke may reduce heat dissipation. As a result, stable motor performance may not be achieved. [Means for solving the problem]

[0007] The coil substrate of the present invention comprises a flexible substrate having a first surface and a second surface opposite to the first surface, and a plurality of coils formed by wiring provided on the first surface and the second surface. The coil substrate can be formed into a cylindrical shape by winding it circumferentially around an axis extending in a direction perpendicular to the longitudinal direction, starting from a first end in the longitudinal direction of the flexible substrate. The flexible substrate has a first region near the first end and a second region adjacent to the first region. Of the wiring, the width of the first wiring formed in the first region is wider than the width of the second wiring formed in the second region.

[0008] In the coil substrate of the embodiment of the present invention, the width of the first wiring formed in the first region is wider than the width of the second wiring formed in the second region. When the coil substrate is wound in the circumferential direction, the second region is located in a layer further outward than the first region. The number of gaps between wirings in the outermost layer is greater than the number of gaps in the innermost layer. As a result, the overlap between the gaps between wirings located on the outermost periphery is reduced. When the coil substrate is wound in the circumferential direction, it is less likely to bend even if force is applied to the gaps between the wiring. When the coil substrate is wound in the circumferential direction, there are no wirings in the gaps between the wiring, so force is easily applied and it is prone to bending. Therefore, when the coil substrate of the embodiment is wound in the circumferential direction to form a motor coil substrate, the motor coil substrate can be formed in a cylindrical shape with a nearly circular cross-section. As a result, the occurrence of short circuits between wirings is suppressed. In addition, when forming a motor in which the motor coil substrate, magnets, and yoke are arranged inside a housing, interference between the magnets placed inside the motor coil substrate and the motor coil substrate is prevented. Furthermore, since the air gap between the motor coil substrate and the yoke remains constant, high heat dissipation is achieved. Therefore, when a motor is formed using the coil substrate of this embodiment, a motor with stable performance can be obtained.

[0009] The motor coil substrate of the present invention is formed by winding the above-described coil substrate of the present invention into a cylindrical shape. The coil substrate is wound around the axis starting from the first end, with the first surface positioned on the inner side and the second surface positioned on the outer side, the first wiring positioned in the innermost first layer and the second wiring positioned in the second layer which is outside the first layer.

[0010] As described above, the motor coil substrate of the embodiment of the present invention can be formed in a cylindrical shape with a substantially circular cross-section. Interference between the magnet and the motor coil substrate during motor formation is prevented. High heat dissipation is achieved. Therefore, when a motor is formed using the motor coil substrate of the embodiment, a motor with stable performance can be obtained.

[0011] The motor of the present invention is formed by placing the above-described motor coil substrate inside a cylindrical yoke, and arranging a rotating shaft and a magnet inside the motor coil substrate.

[0012] In the motor according to the embodiment of the present invention, interference between the magnet and the motor coil substrate is prevented. Furthermore, since the air gap between the motor coil substrate and the yoke remains constant, high heat dissipation is achieved. A motor with stable performance can be obtained. [Brief explanation of the drawing]

[0013] [Figure 1] A schematic plan view showing the coil substrate of the embodiment. [Figure 2] A schematic bottom view showing the coil substrate of the embodiment. [Figure 3] A schematic cross-sectional view showing the coil substrate of the embodiment. [Figure 4] A schematic perspective view showing the motor coil board of the embodiment. [Figure 5] A schematic cross-sectional diagram showing a portion of the motor coil substrate of the embodiment. [Figure 6] A schematic cross-sectional view showing the motor of the embodiment. [Figure 7] A schematic plan view showing the coil substrate of a modified example. [Figure 8] A schematic cross-sectional view showing the coil substrate of a modified example. [Figure 9] A schematic cross-sectional diagram showing a portion of the motor coil circuit board in a modified example. [Modes for carrying out the invention]

[0014] [Embodiment] Figure 1 is a plan view showing the coil substrate 2 of the embodiment. Figure 2 is a bottom view showing the coil substrate 2 of the embodiment. Figure 3 is a cross-sectional view of a part of the coil substrate 2. Figure 3 is a cross-sectional view between III-III in Figures 1 and 2. The coil substrate 2 of the embodiment has a flexible substrate 10 and a plurality of coils 20, 22, and 24.

[0015] 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 a resin having insulation properties such as polyimide and polyamide. The flexible substrate 10 has flexibility. The flexible substrate 10 is formed in a rectangular shape having four sides of a first side E1 to a fourth side E4. The first side E1 is a short side at one end side in the longitudinal direction (the direction of arrow LD in FIG. 1) of the flexible substrate 10. The second side E2 is a short side at the other end side in the longitudinal direction. Both the first side E1 and the second side E2 are short sides extending along an orthogonal direction (the direction of arrow OD in FIG. 1) orthogonal to the longitudinal direction. Both the third side E3 and the fourth side E4 are long sides extending along the longitudinal direction. As will be described in detail later, when the coil substrate 2 is wound in a cylindrical shape to form a motor coil substrate 50 (see FIG. 4), the first surface 10F is disposed on the inner peripheral side and the second surface 10B is disposed on the outer peripheral side.

[0016] The flexible substrate 10 has a first region R1 near the first side E1 and a second region R2 adjacent to the first region R1. The second region R2 extends from adjacent to the first region R1 to near the second side E2.

[0017] The coils 20, 22, 24 are arranged along the longitudinal direction of the flexible substrate 10. Only three coils 20, 22, 24 are shown in FIG. 1. Other coils other than the coils 20, 22, 24 may be provided between the coil 20 and the coil 22 and between the coil 22 and the coil 24 on the flexible substrate 10. The coil 20 is formed in the first region R1. The coils other than the coil 20 (i.e., the coils 22, 24) are formed in the second region R2.

[0018] The coil 20 is composed of a coil-shaped wiring 30F (FIG. 1) provided on the first surface 10F and a coil-shaped wiring 30B (FIG. 2) provided on the second surface 10B. The wirings 30F, 30B are formed in the first region R1 of the flexible substrate 10. The wiring 30F and the wiring 30B are electrically connected via a via conductor 40 penetrating the flexible substrate 10.

[0019] As shown in FIG. 1, the wiring 30F is formed in a right-handed spiral shape (hexagonal spiral shape) from the outer circumference toward the inner circumference. The via conductor 40 is formed at the inner circumferential end of the wiring 30F. As shown in FIG. 2, the wiring 30B is formed in a left-handed spiral shape (hexagonal spiral shape) from the inner circumference toward the outer circumference. Both the wirings 30F and 30B are formed for three turns (for three circumferences). The wirings 30F and 30B are formed in a spiral shape with the same winding direction when viewed from the same plane. The wirings 30F and 30B function as one coil 20 electrically connected in series.

[0020] As shown in FIG. 3, the wiring 30F on the first surface 10F and the wiring 30B on the second surface 10B overlap when projected onto the first surface 10F with light perpendicular to the first surface 10F. That is, the wirings 30F and 30B overlap via the flexible substrate 10 in the thickness direction (the vertical direction in the figure).

[0021] Similarly, the coil 22 is composed of a wiring 32F (FIG. 1) provided on the first surface 10F and a wiring 32B (FIG. 2) provided on the second surface 10B. The wirings 32F and 32B are formed in the second region R2 of the flexible substrate 10. The wirings 32F and 32B are electrically connected via a via conductor 42.

[0022] The wiring 32F is formed in a right-handed spiral shape (hexagonal spiral shape) from the outer circumference toward the inner circumference. The via conductor 42 is formed at the inner circumferential end of the wiring 32F. The wiring 32B is formed in a left-handed spiral shape (hexagonal spiral shape) from the inner circumference toward the outer circumference. Both the wirings 32F and 32B are formed for four turns. The wirings 32F and 32B are formed in a spiral shape with the same winding direction when viewed from the same plane. The wirings 32F and 32B function as one coil 22 electrically connected in series.

[0023] As shown in Figure 3, wiring 32F and wiring 32B overlap when projected onto the first surface 10F with light perpendicular to the first surface 10F. That is, wiring 32F and wiring 32B overlap in the thickness direction (vertical direction in the figure) via the flexible substrate 10. The width W32 of wiring 32F and 32B is smaller than the width W30 of wiring 30F and 30B of coil 20. The spacing between wiring 32F and 32B is the same as the spacing between wiring 30F and 30B of coil 20.

[0024] Similarly, the coil 24 consists of wiring 34F (Figure 1) provided on the first surface 10F and wiring 34B (Figure 2) provided on the second surface 10B. Wirings 34F and 34B are formed in the second region R2 of the flexible substrate 10. Wirings 34F and 34B are electrically connected via a via conductor 44.

[0025] Wiring 34F is formed in a clockwise spiral shape (hexagonal spiral) from the outer circumference to the inner circumference. Via conductor 44 is formed at the inner circumference end of wiring 34F. Wiring 34B is formed in a counterclockwise spiral shape (hexagonal spiral) from the inner circumference to the outer circumference. Both wiring 34F and 34B are formed for 5 turns. Wiring 34F and wiring 34B are formed in the same spiral shape with the same winding direction when viewed from the same plane. Wiring 34F and wiring 34B function as a single coil 24 that is electrically connected in series.

[0026] As shown in Figure 3, wiring 34F and wiring 34B overlap when projected onto the first surface 10F with light perpendicular to the first surface 10F. That is, wiring 34F and wiring 34B overlap in the thickness direction (vertical direction in the figure) via the flexible substrate 10. The width W34 of wiring 34F and 34B is smaller than the width W32 of wiring 32F and 32B of coil 22. That is, the width W34 of wiring 34F and 34B is smaller than the width W30 of wiring 30F and 30B of coil 20. The spacing between wiring 34F and 34B is the same as the spacing between wiring 32F and 32B of coil 22 (i.e., the spacing between wiring 30F and 30B of coil 20).

[0027] Although not shown in the diagram, the first surface 10F and the wiring 30F, 32F, 34F, etc. on the first surface 10F are covered with a resin insulating layer. Similarly, the second surface 10B and the wiring 30B, 32B, 34B, etc. on the second surface 10B are covered with a resin insulating layer.

[0028] Figure 4 is a schematic perspective view showing a motor coil substrate 50 using the coil substrates of the embodiment (Figures 1 to 3). As shown in Figure 4, the motor coil substrate 50 for the motor is formed by winding the coil substrate 2 of the embodiment (Figures 1 and 2) into a cylindrical shape. When the coil substrate 2 is wound into a cylindrical shape, it is wound multiple times in the circumferential direction around an axis extending in a perpendicular direction (an axis extending parallel to the first side E1), starting from the first side E1 (Figure 1). The number of times the coil substrate 2 is wound is not particularly limited. When the coil substrate 2 is wound into a cylindrical shape, the first surface 10F of the flexible substrate 10 is positioned on the inner circumference side, and the second surface 10B is positioned on the outer circumference side.

[0029] Figure 5 is a schematic cross-sectional diagram illustrating a portion of the motor coil substrate 50 shown in Figure 4. As shown in the figure, in the motor coil substrate 50, the first region R1 forms the innermost layer. The second region R2 forms a layer outside the innermost layer.

[0030] As described above, in the coil substrate 2 of the embodiment, the width W30 of the wirings 30F and 30B formed in the first region R1 is wider than the widths W32 and W34 of the wirings 32F, 32B, 34F, and 34B formed in the second region R2 (see Figure 3). The number of turns of the coils 22 and 24 formed by the wirings 32F, 32B, 34F, and 34B is greater than the number of turns of the coil 20 formed by the wirings 30F and 30B. Therefore, the number of gaps between wirings in the outermost layer is greater than the number of gaps in the innermost layer (see Figure 5). As a result, the overlap between the gaps between wirings located on the outermost periphery is reduced compared to the gaps between wirings located on the inner periphery. When the coil substrate 2 is wound in the circumferential direction, it is less likely to bend even if force is applied to the gaps between the wirings. Therefore, when the coil substrate 2 of the embodiment is wound in the circumferential direction to form a motor coil substrate 50, the motor coil substrate 50 can be formed in a cylindrical shape with a nearly circular cross-section.

[0031] Figure 6 is a schematic cross-sectional view showing a motor 100 using the motor coil substrate 50 (Figures 4 and 5) of the embodiment. The motor 100 is formed by placing the motor coil substrate 50 inside the yoke 60, and arranging a rotating shaft 80 and a magnet 70 fixed to the rotating shaft 80 inside the motor coil substrate 50.

[0032] As described above, the configurations of the coil substrate 2 (Figures 1-3), motor coil substrate 50 (Figures 4 and 5), and motor 100 (Figure 6) of the embodiment have been explained. As described above, by using the coil substrate 2 of the embodiment, the motor coil substrate 50 can be formed in a cylindrical shape with a substantially circular cross-section. As a result, the occurrence of short circuits between wiring is suppressed. In addition, interference between the magnet 70, which is placed inside the motor coil substrate 50, and the motor coil substrate 50 is prevented when the motor 100 is formed. Furthermore, since the air gap between the motor coil substrate 50 and the yoke 60 becomes constant, high heat dissipation is achieved. Therefore, when the motor 100 is formed using the coil substrate 2 of the embodiment, a motor 100 with stable performance can be obtained.

[0033] Wiring 30F and 30B in the embodiment is an example of "first wiring". Wiring 32F, 32B, 34F, and 34B is an example of "second wiring". Coil 20 is an example of "first coil". Coils 22 and 24 are examples of "second coil".

[0034] [Another example of an embodiment] In another embodiment, coils 20, 22, and 24 have the same number of turns.

[0035] [Examples of modifications to the embodiment] Figures 7 to 9 show modified examples of the embodiment. In the modified examples, the arrangement of the wiring constituting coils 20, 22, and 24 differs from that of the embodiment. Figure 7 is a plan view showing the coil substrate 102 of the modified example. Figure 8 is a cross-sectional view of a part of the coil substrate 102. Figure 8 is a cross-sectional view between VIII-VIII in Figure 7.

[0036] As shown in Figures 7 and 8, the modified coil 20 is formed such that the wiring 30F constituting half a turn of one turn is formed on the first surface 10F side, and the wiring 30B constituting the remaining half turn is formed on the second surface 10B side, with adjacent turns being arranged with a staggered arrangement. The coil 20 comprises wiring 30F and 30B for three turns. The wiring 30F and wiring 30B constituting each turn are electrically connected via via conductors 40 that penetrate the flexible substrate 10. Both the wiring 30F and wiring 30B constituting the coil 20 are formed in the first region R1.

[0037] Similarly, the coil 22 is formed by arranging the wiring 32F, which constitutes half a turn in one turn, on the first surface 10F side, and the wiring 32B, which constitutes the remaining half turn, on the second surface 10B side, with each adjacent turn being offset from the others. However, the coil 22 has wiring 32F and 32B for four turns. The wiring 32F and 32B that constitute each turn are electrically connected via a via conductor 42. The wiring 32F and 32B are formed across the first region R1 and the second region R2.

[0038] As shown in Figure 8, the width W32 of wiring 32F and 32B is smaller than the width W30 of wiring 30F and 30B of coil 20. The spacing between wiring 32F and 32B is the same as the spacing between wiring 30F and 30B of coil 20.

[0039] Coil 24 is formed by arranging wiring 34F, which constitutes half a turn of one coil, on the first surface 10F side, and wiring 34B, which constitutes the remaining half turn, on the second surface 10B side, with adjacent turns being offset from each other. However, coil 24 has wiring for 5 turns. Wiring 34F and wiring 34B that constitute each turn are electrically connected via via conductor 44. Wirings 34F and 34B are formed in the second region R2.

[0040] As shown in Figure 8, the width W34 of wiring 34F and 34B is smaller than the width W32 of wiring 32F and 32B of coil 22. That is, the width W34 of wiring 34F and 34B is smaller than the width W30 of wiring 30F and 30B of coil 20. The spacing between wiring 34F and 34B is the same as the spacing between wiring 32F and 32B of coil 22 (i.e., the spacing between wiring 30F and 30B of coil 20).

[0041] Although not shown in the diagram, the first surface 10F and wiring 30F, 32F, and 34F are covered with a resin insulating layer. Similarly, the second surface 10B and wiring 30B, 32B, and 34B are covered with a resin insulating layer.

[0042] In the modified example, the above-mentioned coil substrate 102 (Figures 7 and 8) is wound multiple times in the circumferential direction starting from the first side E1 to form the motor coil substrate 50 (see Figure 4). The number of times the coil substrate 102 is wound is not particularly limited. In the motor coil substrate 50, the first surface 10F of the flexible substrate 10 is positioned on the inner circumference side, and the second surface 10B is positioned on the outer circumference side.

[0043] Figure 9 is a schematic cross-sectional diagram showing a portion of the modified motor coil substrate 50. As shown in Figure 9, in the modified motor coil substrate 50, the first region R1 forms the innermost layer. The second region R2 forms a layer outside the innermost layer.

[0044] As described above, in the coil substrate 2 of the embodiment, the width W30 of the wirings 30F and 30B formed in the first region R1 is wider than the widths W32, W34, etc. of the wirings 32F, 32B, 34F, and 34B formed in the second region R2 (see Figure 8). The number of turns of the coils 22 and 24 formed by the wirings 32F, 32B, 34F, and 34B is greater than the number of turns of the coil 20 formed by the wirings 30F and 30B. Therefore, the number of gaps between wirings in the outermost layer is greater than the number of gaps in the innermost layer. As a result, the overlap between the gaps between wirings located on the outermost periphery is reduced compared to the gaps between wirings located on the inner periphery. When the coil substrate 2 is wound in the circumferential direction, it is less likely to bend even if force is applied to the gaps between the wirings. Therefore, when the coil substrate 2 of the embodiment is wound in the circumferential direction to form a motor coil substrate 50, the motor coil substrate 50 can be formed in a cylindrical shape with a nearly circular cross-section.

[0045] Wiring 30F and 30B in the embodiment is an example of "first wiring". Wiring 32F, 32B, 34F, and 34B is an example of "second wiring". Coil 20 is an example of "first coil". Coils 22 and 24 are examples of "second coil".

[0046] [Another example of modification] In another example of the modification, the number of turns for coils 20, 22, and 24 are equal. [Explanation of symbols]

[0047] 2,102: Coil board 10: Flexible circuit board 10F: 1st page 10B: 2nd side 20, 22, 24: Coil 30F, 32F, 34F: Wiring (on the first surface) 30B, 32B, 34B: Wiring (on the second plane) 40, 42, 44: Via conductors 50: Motor coil board 60: York 70: Magnet 80: Rotation axis 100: Motor E1: First side E2: Second side E3: Third side E4: Fourth side R1: 1st area R2: 2nd area

Claims

1. A motor coil substrate is formed by winding multiple coil substrates around the flexible substrate, each of which can be formed into a cylindrical shape by winding around an axis extending in a direction perpendicular to the longitudinal direction, starting from a first end in the longitudinal direction of the flexible substrate, the flexible substrate having a first surface and a second surface opposite to the first surface, and wherein the coil substrate is formed by winding multiple coil substrates around the flexible substrate in a direction perpendicular to the longitudinal direction, The flexible substrate has a first region near the first end and a second region adjacent to the first region. Of the aforementioned wirings, the width of the first wiring formed in the first region is wider than the width of the second wiring formed in the second region. The coil substrate is wound around the axis starting from the first end, with the first surface facing the inner side and the second surface facing the outer side, the first wiring is located in the innermost first layer, and the second wiring is located in the second layer which is outside the first layer.

2. A motor coil substrate according to claim 1, wherein the plurality of coils include a first coil formed by the first wiring and a second coil formed by the second wiring, and the number of turns of the second coil is greater than the number of turns of the first coil.

3. A motor formed by arranging the motor coil substrate according to claim 1 inside a cylindrical yoke, and arranging a rotating shaft and magnets inside the motor coil substrate.

Images