Coil arrangement and actuator

By employing a specific offset design of the first and second printed wiring boards in the coil assembly, the problem of torque variation caused by the rotating phase is solved, achieving torque stability and uniformity.

CN122178615APending Publication Date: 2026-06-09SUMITOMO ELECTRIC PRINTED CIRCUITS INC
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
SUMITOMO ELECTRIC PRINTED CIRCUITS INC
Filing Date
2025-12-03
Publication Date
2026-06-09

AI Technical Summary

Technical Problem

In existing coil devices, the torque changes drastically when the rotational phase changes, leading to instability.

Method used

The design employs first and second printed wiring boards, wherein the second printed wiring board is offset circumferentially such that multiple second coil portions overlap with two adjacent first coil portions when viewed from above, forming a specific coil layout.

Benefits of technology

It effectively suppresses torque fluctuations caused by the rotation phase, and improves the rotational stability and torque uniformity of the coil device.

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Abstract

Provided is a coil device capable of suppressing variation in torque caused by rotational phase. The coil device includes a first printed wiring board and a second printed wiring board. The first printed wiring board includes a first base film having a first main face, and a first wiring disposed on the first main face. The first wiring includes a plurality of first coil portions that are arranged in a circumferential direction when viewed from above, and that are wound in a spiral shape. The second printed wiring board includes a second base film having a second main face and a third main face, and a second wiring disposed on the second main face. The third main face faces the first main face. The second wiring includes a plurality of second coil portions that are arranged in a circumferential direction when viewed from above, and that are wound in a spiral shape.
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Description

Technical Field

[0001] This disclosure relates to coil devices and actuators. Background Technology

[0002] Japanese Patent Application Publication No. 2024-71959 (Patent Document 1) discloses an axial clearance motor. The axial clearance motor described in Patent Document 1 includes a coil assembly and a magnet. The coil assembly has a substrate and multiple wound coils disposed on the substrate. When viewed from above, the multiple wound coils are arranged in a ring shape along the circumference. Through the interaction between the magnetic field generated by the magnet and the current flowing in the wound coils, a torque is generated in the multiple wound coils that causes the coil assembly to rotate circumferentially.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2024-71959 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] In the coil arrangement of the axial clearance motor described in Patent Document 1, the aforementioned torque varies significantly due to the rotational phase. This disclosure is made in view of such prior art. More specifically, this disclosure provides a coil arrangement capable of suppressing torque variations caused by the rotational phase.

[0008] Solutions for solving technical problems

[0009] The coil device disclosed herein includes a first printed wiring board and a second printed wiring board. The first printed wiring board has: a first base film having a first main surface; and a first wiring disposed on the first main surface. The first wiring has a plurality of first coil portions that, when viewed from above, are wound into a spiral shape and arranged circumferentially. The second printed wiring board has: a second base film having a second main surface and a third main surface; and a second wiring disposed on the second main surface. The third main surface faces the first main surface. The second wiring has a plurality of second coil portions that, when viewed from above, are wound into a spiral shape and arranged circumferentially. The second printed wiring board is offset circumferentially relative to the first printed wiring board in such a way that, when viewed from above, one of the multiple second coil portions overlaps with two adjacent first coil portions of the multiple first coil portions.

[0010] Invention Effects

[0011] According to the coil device of this disclosure, it is possible to suppress torque variations caused by the rotation phase. Attached Figure Description

[0012] Figure 1This is a top view of the coil device 100.

[0013] Figure 2 This is a second top view of the coil device 100.

[0014] Figure 3 This is the third top view of the coil device 100.

[0015] Figure 4 This is the fourth top view of the coil device 100.

[0016] Figure 5 yes Figure 3 A cross-sectional view at point VV.

[0017] Figure 6 yes Figure 3 The sectional view at VI-VI.

[0018] Figure 7 This is a first cross-sectional view illustrating the operation of the coil device 100.

[0019] Figure 8 This is a second sectional view illustrating the operation of the coil device 100.

[0020] Figure 9 It is a graph showing the torque applied to the plurality of coil sections 33 and the plurality of coil sections 43 in the coil device involved in the comparative example.

[0021] Figure 10 This is a graph showing the torque applied to multiple coil sections 33 and multiple coil sections 43 in the coil device involved in the comparative example during power control.

[0022] Figure 11 It is a graph showing the torque applied to the plurality of coil sections 33 and the plurality of coil sections 43 in the coil device 100.

[0023] Figure 12 It is a graph showing the torque applied to the plurality of coil sections 33 and the plurality of coil sections 43 in the coil device 100 during power control.

[0024] Figure 13 It is a graph showing the resultant torque applied to the coil device 100 during power control.

[0025] Explanation of reference numerals in the attached figures

[0026] 10, 20 Printed Wiring Boards

[0027] 30 base film

[0028] 30a, 30b Main face

[0029] 31, 32 Wiring

[0030] Coil section of 33, 33A, 33B, 33C, 33D, 33E, 33F

[0031] 33a Part 1

[0032] 33b Part Two

[0033] 33c Part Three

[0034] 33d Part 4

[0035] Coil section of models 34, 34A, 34B, 34C, 34D, 34E, and 34F.

[0036] 34a Part 1

[0037] 34b Part Two

[0038] 34c Part Three

[0039] 34d Part Four

[0040] Pads 35 and 36

[0041] 37, 38 Connecting parts

[0042] 40 base film

[0043] 40a, 40b Main face

[0044] 41, 42 Wiring

[0045] 43, 43A, 43B, 43C, 43D, 43E, 43F Coil Section

[0046] 43a Part 1

[0047] 43b Part Two

[0048] 43c Part 3

[0049] 43d Part Four

[0050] 44, 44A, 44B, 44C, 44D, 44E, 44F Coil Section

[0051] 44a Part 1

[0052] 44b Part Two

[0053] 44c Part 3

[0054] 44d Part Four

[0055] Pads 45 and 46

[0056] 47, 48 Connecting parts

[0057] 50 bonding layer

[0058] 60 magnets

[0059] 100 coil device

[0060] DR1 Zhou Xiang

[0061] DR2 Radial. Detailed Implementation

[0062] [Description of embodiments of this disclosure]

[0063] First, embodiments of this disclosure will be described.

[0064] (1) The coil device according to the embodiment includes a first printed wiring board and a second printed wiring board. The first printed wiring board has: a first base film having a first main surface; and a first wiring disposed on the first main surface. The first wiring has a plurality of first coil portions that are wound into a spiral shape and arranged circumferentially when viewed from above. The second printed wiring board has: a second base film having a second main surface and a third main surface; and a second wiring disposed on the second main surface. The third main surface faces the first main surface. The second wiring has a plurality of second coil portions that are wound into a spiral shape and arranged circumferentially when viewed from above. The second printed wiring board is offset circumferentially relative to the first printed wiring board in such a way that one of the second coil portions overlaps with two adjacent first coil portions among the plurality of first coil portions when viewed from above. According to the coil device of (1) above, the torque variation caused by the rotation phase can be suppressed.

[0065] (2) In the coil arrangement described in (1) above, the plurality of first coil portions may each have a first portion and a second portion that extend circumferentially and are spaced apart from each other in a radial direction perpendicular to the circumferential direction when viewed from above. The plurality of second coil portions may each have a third portion and a fourth portion that extend radially and are spaced apart from each other in a circumferential direction when viewed from above. The second printed wiring board may also be offset circumferentially relative to the first printed wiring board in such a way that, when viewed from above, the third portion of one second coil portion overlaps with the first and second portions of one of the two adjacent first coil portions, and when viewed from above, the fourth portion of one second coil portion overlaps with the first and second portions of the other of the two adjacent first coil portions. According to the coil arrangement described in (2) above, the torque variation caused by the rotation phase can be further suppressed.

[0066] (3) In the coil device described in (1) or (2) above, the first base film may also have a fourth main surface. The first printed wiring board may also have a third wiring disposed on the fourth main surface. The third wiring may also have a plurality of third coil portions that are wound into a spiral shape and arranged circumferentially when viewed from above. The plurality of third coil portions may also overlap with a plurality of first coil portions when viewed from above. The second printed wiring board may also have a fourth wiring disposed on the third main surface. The fourth wiring may also have a plurality of fourth coil portions that are wound into a spiral shape and arranged circumferentially when viewed from above. The plurality of fourth coil portions may also overlap with a plurality of second coil portions when viewed from above.

[0067] (4) The coil device according to other embodiments includes a printed wiring board. The printed wiring board has: a base film having a first main surface and a second main surface; a first wiring disposed on the first main surface; and a second wiring disposed on the second main surface. The first wiring has a plurality of first coil portions that are wound into a spiral shape and arranged circumferentially when viewed from above. The second wiring has a plurality of second coil portions that are wound into a spiral shape and arranged circumferentially when viewed from above. When viewed from above, one of the plurality of second coil portions is offset circumferentially by overlapping with two adjacent first coil portions among the plurality of first coil portions. According to the coil device of (4) above, the torque variation caused by the rotation phase can be suppressed.

[0068] (5) The actuator according to the embodiment includes: the coil device described in (1) to (4) above; and a magnet that generates a magnetic field along the normal direction of the first principal surface and the second principal surface. According to the actuator described in (5), the torque variation caused by the rotation phase can be further suppressed in the coil device.

[0069] [Details of the embodiments of this disclosure]

[0070] Next, while referring to the appendix Figure 1 The details of embodiments of this disclosure will be described below. In the following drawings, the same or equivalent parts will be labeled with the same reference numerals, and repeated descriptions will not be given. The coil device involved in the embodiment will be referred to as coil device 100.

[0071] (Structure of coil device 100)

[0072] The structure of the coil device 100 will be described below.

[0073] Figure 1 This is a top view of the coil device 100. Figure 2 This is a second top view of the coil device 100. Figure 3 This is the third top view of the coil device 100. Figure 4This is the fourth top view of the coil device 100. Figure 1 The printed wiring board 20 is omitted from the diagram. Figure 4 The printed wiring board 10 is omitted from the illustration. Figure 2 and Figure 4 The text shows the relationship between... Figure 1 and Figure 3 A top view of the coil device 100 viewed from the opposite direction. (See image) Figures 1 to 4 As shown, the coil device 100 has a printed wiring board 10 and a printed wiring board 20.

[0074] The printed wiring board 10 has a base film 30, wiring 31, and wiring 32. The base film 30 has a main surface 30a and a main surface 30b. The main surface 30b is the surface opposite to the main surface 30a. The main surfaces 30a and 30b are the end faces of the base film 30 in the thickness direction. The base film 30 is formed of a flexible, electrically insulating material. For example, the base film 30 is formed of polyimide.

[0075] Wiring 31 is disposed on the main surface 30a. Wiring 31 has multiple coil portions 33. The multiple coil portions 33 are arranged in a ring shape when viewed from above. Sometimes the direction in which the multiple coil portions 33 are arranged is called circumferential DR1. Sometimes the direction perpendicular to circumferential DR1 is called radial DR2. In the illustrated example, wiring 31 has six coil portions 33. These six coil portions 33 are designated as coil portion 33A, coil portion 33B, coil portion 33C, coil portion 33D, coil portion 33E, and coil portion 33F. When viewed from the main surface 30a side, coil portion 33A, coil portion 33B, coil portion 33C, coil portion 33D, coil portion 33E, and coil portion 33F are arranged clockwise in sequence. The coil portions 33 are formed by winding wiring 31 into a spiral shape when viewed from above. It should be noted that the winding direction of the wiring 31 of one of the two adjacent coil sections 33 is opposite to the winding direction of the wiring 31 of the other of the two adjacent coil sections 33.

[0076] The coil portion 33 has a first portion 33a, a second portion 33b, a third portion 33c, and a fourth portion 33d. The first portion 33a and the second portion 33b extend circumferentially along DR1 when viewed from above, and are separated from each other radially along DR2 when viewed from above. The third portion 33c and the fourth portion 33d extend radially along DR2 when viewed from above, and are separated from each other circumferentially along DR1 when viewed from above.

[0077] Wiring 32 is disposed on the main surface 30b. Wiring 32 has a plurality of coil portions 34. The plurality of coil portions 34 are arranged in a circumferential ring when viewed from above. In the illustrated example, wiring 32 has six coil portions 34. These six coil portions 34 are designated as coil portion 34A, coil portion 34B, coil portion 34C, coil portion 34D, coil portion 34E, and coil portion 34F. When viewed from the main surface 30b side, coil portions 34A, coil portion 34B, coil portion 34C, coil portion 34D, coil portion 34E, and coil portion 34F are arranged counterclockwise in sequence.

[0078] The coil portion 34 is formed by winding the wiring 32 into a spiral shape when viewed from above. It should be noted that the winding direction of the wiring 32 of one of the two adjacent coil portions 34 is opposite to the winding direction of the wiring 32 of the other of the two adjacent coil portions 34. The coil portion 34 has a first portion 34a and a second portion 34b that extend circumferentially DR1 when viewed from above and are separated from each other radially DR2 when viewed from above, and a third portion 34c and a fourth portion 34d that extend radially DR2 when viewed from above and are separated from each other circumferentially DR1 when viewed from above.

[0079] When viewed from above, each of the multiple coil portions 34 overlaps with a plurality of coil portions 33. More specifically, coil portions 34A, 34B, 34C, 34D, 34E, and 34F overlap with coil portions 33A, 33B, 33C, 33D, 33E, and 33F, respectively, when viewed from above. It should be noted that one of the multiple coil portions 34 overlaps only with one of the multiple coil portions 33 when viewed from above, and does not overlap with the other coil portions 33. When viewed from above, the first portion 34a and the second portion 34b overlap with the first portion 33a and the second portion 33b, respectively, and the third portion 34c and the fourth portion 34d overlap with the third portion 33c and the fourth portion 33d, respectively.

[0080] Wiring 31 also has a plurality of pads 35. The plurality of pads 35 are respectively connected to the innermost periphery of each of the plurality of coil portions 33. Wiring 32 also has a plurality of pads 36. The plurality of pads 36 are respectively connected to the innermost periphery of each of the plurality of coil portions 34. The plurality of pads 36 overlap with the plurality of pads 35 when viewed from above, and are electrically connected to the plurality of pads 35.

[0081] Wiring 31 also has a plurality of connecting portions 37. The plurality of connecting portions 37 are respectively connected to the outermost periphery of each of the plurality of coil portions 33. Wiring 32 also has a plurality of connecting portions 38. The plurality of connecting portions 38 are respectively connected to the outermost periphery of the coil portion 34.

[0082] A connecting part 37 is connected to coil part 33A and electrically connected to a power terminal (not shown). A connecting part 38 is connected to coil part 34F and also connected to a power terminal (not shown). Although not shown, another connecting part 38 is electrically connected to coil part 34A and to another connecting part 37 connected to coil part 33B. Similarly, coil part 34B is electrically connected to coil part 33C, coil part 34C to coil part 33D, coil part 34D to coil part 33E, and coil part 34E to coil part 33F via connecting parts 37 and 38.

[0083] The printed wiring board 20 has a base film 40, wiring 41, and wiring 42. The base film 40 has a main surface 40a and a main surface 40b. The main surface 40b is the surface opposite to the main surface 40a. The main surfaces 40a and 40b are end faces of the base film 40 in the thickness direction. The base film 40 is formed of a flexible, electrically insulating material. The base film 40 is, for example, formed of polyimide.

[0084] Wiring 41 is disposed on the main surface 40a. Wiring 41 has multiple coil portions 43. The multiple coil portions 43 are arranged in a ring shape when viewed from above. In the illustrated example, wiring 41 has six coil portions 43. These six coil portions 43 are designated as coil portion 43A, coil portion 43B, coil portion 43C, coil portion 43D, coil portion 43E, and coil portion 43F. When viewed from the main surface 40a side, coil portions 43A, coil portion 43B, coil portion 43C, coil portion 43D, coil portion 43E, and coil portion 43F are arranged clockwise in sequence. The coil portions 43 are formed by winding the wiring 41 into a spiral shape when viewed from above. It should be noted that the winding direction of wiring 41 in one of two adjacent coil portions 43 is opposite to the winding direction of wiring 41 in the other of the two adjacent coil portions 43.

[0085] The coil portion 43 has a first portion 43a, a second portion 43b, a third portion 43c, and a fourth portion 43d. The first portion 43a and the second portion 43b extend circumferentially along DR1 when viewed from above, and are separated from each other radially along DR2 when viewed from above. The third portion 43c and the fourth portion 43d extend radially along DR2 when viewed from above, and are separated from each other circumferentially along DR1 when viewed from above.

[0086] Wiring 42 is disposed on the main surface 40b. Wiring 42 has a plurality of coil portions 44. The plurality of coil portions 44 are arranged in a circumferential ring when viewed from above. In the illustrated example, wiring 42 has six coil portions 44. These six coil portions 44 are designated as coil portion 44A, coil portion 44B, coil portion 44C, coil portion 44D, coil portion 44E, and coil portion 44F. When viewed from the main surface 40b side, coil portions 44A, coil portion 44B, coil portion 44C, coil portion 44D, coil portion 44E, and coil portion 44F are arranged in a counterclockwise order.

[0087] The coil portion 44 is formed by winding the wiring 42 into a spiral shape when viewed from above. It should be noted that the winding direction of the wiring 42 of one of the two adjacent coil portions 44 is opposite to the winding direction of the wiring 42 of the other of the two adjacent coil portions 44. The coil portion 44 has a first portion 44a and a second portion 44b that extend circumferentially DR1 when viewed from above and are separated from each other radially DR2 when viewed from above, and a third portion 44c and a fourth portion 44d that extend radially DR2 when viewed from above and are separated from each other circumferentially DR1 when viewed from above.

[0088] When viewed from above, each of the multiple coil portions 44 overlaps with a plurality of coil portions 43. More specifically, coil portions 44A, 44B, 44C, 44D, 44E, and 44F overlap with coil portions 43A, 43B, 43C, 43D, 43E, and 43F, respectively, when viewed from above. It should be noted that one of the multiple coil portions 44 overlaps only with one of the multiple coil portions 43 when viewed from above, and does not overlap with any of the other coil portions 43. When viewed from above, the first portion 44a and the second portion 44b overlap with the first portion 43a and the second portion 43b, respectively, and the third portion 44c and the fourth portion 44d overlap with the third portion 43c and the fourth portion 43d, respectively.

[0089] Wiring 41 also has a plurality of pads 45. The plurality of pads 45 are respectively connected to the innermost periphery of each of the plurality of coil portions 43. Wiring 42 also has a plurality of pads 46. The plurality of pads 46 are respectively connected to the innermost periphery of each of the plurality of coil portions 44. The plurality of pads 46 overlap with the plurality of pads 45 when viewed from above, and are electrically connected to the plurality of pads 45.

[0090] Wiring 41 also has a plurality of connecting portions 47. The plurality of connecting portions 47 are respectively connected to the outermost periphery of each of the plurality of coil portions 43. Wiring 42 also has a plurality of connecting portions 48. The plurality of connecting portions 48 are respectively connected to the outermost periphery of the coil portion 44.

[0091] A connecting part 47 is connected to coil part 43A and electrically connected to a power terminal (not shown). A connecting part 48 is connected to coil part 44F and electrically connected to a power terminal (not shown). Although not shown, another connecting part 48 is electrically connected to coil part 44A and to another connecting part 47 connected to coil part 43B. Similarly, coil part 44B is electrically connected to coil part 43C, coil part 44C to coil part 43D, coil part 44D to coil part 43E, and coil part 44E to coil part 43F via connecting parts 47 and 48.

[0092] It should be noted that wiring 31, wiring 32, wiring 41, and wiring 42 are formed of conductive material. Wiring 31, wiring 32, wiring 41, and wiring 42 are formed, for example, of copper or copper alloy. Wiring 31, wiring 32, wiring 41, and wiring 42 can be formed by a semi-additive method or by a subtractive method.

[0093] Figure 5 yes Figure 3 A cross-sectional view at point VV. Figure 6 yes Figure 3 The sectional view at VI-VI. (See example) Figure 5 and Figure 6 As shown, the printed wiring board 20 overlaps with the printed wiring board 10 such that the main surface 40b is opposite to the main surface 30a. The printed wiring board 20 is attached to the printed wiring board 10 by a bonding layer 50 disposed between the main surface 30a and the main surface 40b.

[0094] like Figure 3 As shown, when viewed from above, the columns of coil portions 34 arranged along the circumferential DR1 overlap with the columns of coil portions 33 arranged along the circumferential DR1. The printed circuit board 20 is offset relative to the printed circuit board 10 along the circumferential DR1 in such a way that when viewed from above, one coil portion 34 overlaps with both adjacent coil portions 33. For example, the third portion 43c of a coil portion 43 overlaps with the first portion 33a and the second portion 33b of one of the two adjacent coil portions 33 when viewed from above, and the fourth portion 43d of the same coil portion 43 overlaps with the first portion 33a and the second portion 33b of the other of the two adjacent coil portions 33 when viewed from above.

[0095] More specifically, for example, when viewed from above, the third portion 43c of coil portion 43A overlaps with the first portion 33a and the second portion 33b of coil portion 33A, and the fourth portion 43d of coil portion 43A overlaps with the first portion 33a and the second portion 33b of coil portion 33B. The same applies to the relationships between coil portion 43B and coil portions 34B and 34C, coil portion 43C and coil portions 34C and 34D, coil portion 43D and coil portions 34D and 34E, coil portion 43E and coil portions 34E and 34F, and coil portion 43F and coil portions 34F and 34A.

[0096] Figure 7 This is a first cross-sectional view illustrating the operation of the coil device 100. Figure 8 This is a second sectional view illustrating the operation of the coil device 100. (See attached image.) Figure 7 and Figure 8As shown, the actuator using the coil device 100 has a magnet 60. The magnet 60 generates a magnetic field (indicated by dashed arrows in the figure) along the normal direction of the principal surface 40a (principal surface 40b, principal surface 30a, principal surface 30b). Figure 7 and Figure 8 In the example shown, the magnetic field moves from the top to the bottom of the diagram.

[0097] When the coil device 100 operates, current flows in wiring 31 and wiring 32, that is, in the plurality of coil sections 33 and coil sections 34. More specifically, in Figure 7 and Figure 8 In the example shown, in parts 33c, 33d, 34c, 34d, 43c, 43d, 44c, and 44d, the current flows from the inside of the paper toward the front of the paper in a direction perpendicular to the paper.

[0098] As a result, through the interaction between the aforementioned magnetic field and current, a thrust is generated along the circumferential direction DR1 in the third part 33c, the fourth part 33d, the third part 34c, the fourth part 34d, the third part 43c, the fourth part 43d, the third part 44c, and the fourth part 44d (indicated by solid arrows in the figure). Since this thrust is along the circumferential direction DR1, the coil device 100 rotates along the circumferential direction DR1 by the torque based on this thrust and functions as an actuator.

[0099] (Effect of coil device 100)

[0100] The effects of the coil device 100 will be explained below while comparing it with the coil device involved in the comparative example.

[0101] In the coil device of the comparative example, the plurality of coil portions 34 overlap with the plurality of coil portions 33 respectively when viewed from above. That is, in the coil device of the comparative example, the printed wiring board 20 overlaps with the printed wiring board 10 in the circumferential direction DR1 without offset when viewed from above, such that one coil portion 34 overlaps with only one coil portion 33. In other respects, the structure of the coil device of the comparative example is common to the structure of the coil device 100.

[0102] Figure 9 It is a graph showing the torque applied to the plurality of coil sections 33 and the plurality of coil sections 43 in the coil device involved in the comparative example. Figure 10 This is a graph showing the torque applied to the plurality of coil sections 33 and the plurality of coil sections 43 in the coil device involved in the comparative example during power control. For example... Figure 9As shown, in the coil device involved in the comparative example, since the printed wiring board 20 is not offset relative to the printed wiring board 10 along the circumferential direction DR1, the phase of the torque applied to the plurality of coil sections 33 is not offset from the phase of the torque applied to the plurality of coil sections 43.

[0103] Furthermore, the torque applied to the plurality of coil sections 33 and the torque applied to the plurality of coil sections 43 vary according to the rotation phase of the coil device involved in the comparative example. This variation in torque caused by the rotation phase occurs because a strong thrust is generated in the portion where the current flows radially along DR2, but no strong thrust is generated in the portion where the current flows circumferentially along DR1. As a result, as... Figure 10 As shown, even if the power supply is controlled in such a way that the torque applied to the multiple coil sections 33 and the torque applied to the multiple coil sections 43 are always positive, the torque applied to the multiple coil sections 33 and the torque applied to the multiple coil sections 43 will vary greatly depending on the rotation phase.

[0104] Figure 11 It is a graph showing the torque applied to the plurality of coil sections 33 and the plurality of coil sections 43 in the coil device 100. Figure 12 It is a graph showing the torque applied to the plurality of coil sections 33 and the plurality of coil sections 43 in the coil device 100 during power control. Figure 13 This is a graph showing the resultant torque applied to the coil device 100 during power supply control. It should be noted that... Figures 11 to 13 The example shown is a case where the phase of the torque applied to the plurality of coil sections 43 is offset by λ / 4 relative to the phase of the torque applied to the plurality of coil sections 33.

[0105] As described above, in the coil assembly 100, the printed wiring board 20 is offset relative to the printed wiring board 10 in the circumferential direction DR1 such that, when viewed from above, one coil portion 43 overlaps with both adjacent coil portions 33. For this purpose, as... Figure 11 As shown, in the coil device 100, the phase of the torque applied to the plurality of coil sections 43 is offset from the phase of the torque applied to the plurality of coil sections 33. Therefore, when power supply control is performed in a manner that keeps both the torque applied to the plurality of coil sections 33 and the torque applied to the plurality of coil sections 43 positive, a peak in the phase of the torque applied to the plurality of coil sections 43 is located between two adjacent peaks in the phase of the torque applied to the plurality of coil sections 33, and the variation of the combined torque applied to the coil device 100 with respect to each rotation phase is reduced.

[0106] From another perspective, in the coil device 100, the portion of the coil section 43 (coil section 44) subjected to enhanced thrust overlaps with the portion of the coil section 33 (coil section 34) not subjected to enhanced thrust, and vice versa. Therefore, fluctuations in the combined torque applied to the coil device 100 caused by the rotation phase are suppressed. Thus, according to the coil device 100, fluctuations in torque and thrust caused by the rotation phase can be suppressed.

[0107] (Modified example)

[0108] In the above description, an example of a coil device 100 having two printed wiring boards (printed wiring board 10 and printed wiring board 20) was given, but the coil device 100 may also have only one printed wiring board. In this case, for example, the coil device 100 does not have printed wiring board 20, and printed wiring board 10 has wiring 41 on the main surface 30b instead of wiring 32. That is, in a single printed wiring board, the multiple coil portions of the wiring disposed on one main surface of the base film 30 may be offset in the circumferential direction DR1 in such a way that they overlap with two adjacent coil portions of the wiring disposed on the other main surface of the base film 30.

[0109] It should be understood that the embodiments disclosed herein are exemplary and not limiting in all respects. The scope of the invention is shown not by the above embodiments but by the claims, and is intended to include all modifications within the meaning and scope of the claims.

Claims

1. A coil device comprising: First printed wiring board; and Second printed wiring board, The first printed wiring board has: a first base film having a first main surface; and a first wiring disposed on the first main surface. The first wiring has a plurality of first coil portions that, when viewed from above, are wound into a vortex shape and arranged circumferentially. The second printed wiring board includes: a second base film having a second main surface and a third main surface; and a second wiring disposed on the second main surface. The third main surface is opposite to the first main surface. The second wiring has a plurality of second coil portions that, when viewed from above, are wound into a spiral shape and arranged along the circumference. The second printed wiring board is offset relative to the first printed wiring board in the circumferential direction such that, when viewed from above, one of the plurality of second coil portions overlaps with two adjacent first coil portions of the plurality of first coil portions.

2. The coil device according to claim 1, wherein, The plurality of first coil portions each have a first portion and a second portion that, when viewed from above, extend along the circumferential direction and are spaced apart from each other along a radial direction perpendicular to the circumferential direction. The plurality of second coil portions each have a third portion and a fourth portion that, when viewed from above, extend radially and are spaced apart from each other circumferentially. The second printed wiring board is offset relative to the first printed wiring board in the circumferential direction such that, when viewed from above, the third portion of the second coil portion overlaps with the first and second portions of one of the two adjacent first coil portions, and when viewed from above, the fourth portion of the second coil portion overlaps with the first and second portions of the other of the two adjacent first coil portions.

3. The coil device according to claim 1, wherein, The first base film has a fourth principal surface. The first printed wiring board also has a third wiring disposed on the fourth main surface. The third wiring has a plurality of third coil portions that, when viewed from above, are wound into a vortex shape and arranged along the circumference. When viewed from above, the plurality of third coil portions overlap with the plurality of first coil portions. The second printed wiring board also has a fourth wiring disposed on the third main surface. The fourth wiring has a plurality of fourth coil portions that, when viewed from above, are wound into a vortex shape and arranged along the circumference. The plurality of fourth coil portions overlap with the plurality of second coil portions when viewed from above.

4. A coil device comprising a printed wiring board, The printed wiring board has: The base film has a first main surface and a second main surface; The first wiring is configured on the first main surface; as well as The second wiring is configured on the second main surface. The first wiring has a plurality of first coil portions that, when viewed from above, are wound into a vortex shape and arranged circumferentially. The second wiring has a plurality of second coil portions that, when viewed from above, are wound into a spiral shape and arranged along the circumference. When viewed from above, one of the plurality of second coil portions is offset in the circumferential direction in such a way that it overlaps with two adjacent first coil portions of the plurality of first coil portions.

5. An actuator comprising: The coil device according to any one of claims 1 to 4; and The magnet generates a magnetic field along the normal direction of the first principal surface and the second principal surface.