Coil substrate for motor, motor, and method for manufacturing coil substrate for motor

Abstract

Provided are a coil substrate for a motor and a motor in which the cross-sectional shape of the coil substrate for a motor can be formed into a true circular shape. A coil substrate for a motor according to an embodiment includes a flexible substrate having a first surface and a second surface opposite from the first surface, and a plurality of coil wirings disposed along the longitudinal direction of the flexible substrate, one end-side end part of the coil substrate for a motor being a winding start part, and the coil substrate for a motor being formed in a substantially cylindrical shape, wherein: the coil substrate for a motor is composed of a coil wiring formation region in which coil wiring is formed on at least one of the first surface and the second surface of the coil substrate, and a coil wiring non-formation region in which coil wiring is not formed on either of the first surface and the second surface of the coil substrate; the coil wiring non-formation region is disposed in the vicinity of a longitudinal-direction end part of the coil substrate; and the longitudinal-direction length L1 of the coil wiring non-formation region and the circumferential-direction length C of the coil substrate for a motor satisfy the relationship in formula 1. Formula 1: 1 / 3 ≤ L1 / C < 1

Description

Motor coil substrate, motor, and method for manufacturing motor coil substrate

[0001] The technology disclosed in this specification relates to a motor coil substrate, a motor, and a method for manufacturing a motor coil substrate.

[0002] Patent Document 1 discloses a coil body formed by winding a printed wiring board on which a wiring pattern is formed multiple times to form a cylindrical shape. The printed wiring board in Patent Document 1 has wiring pattern unformed areas on both sides where no wiring pattern is formed. The wiring pattern unformed areas are provided at the end of the printed wiring board where the winding begins in the circumferential direction, and have a length equal to or greater than the inner circumference of the coil body.

[0003] International Publication No. 2020 / 194627

[0004] <Issues of Patent Document 1> A coil body is formed by winding a printed wiring board into a cylindrical shape around a core material. In the technology of Patent Document 1, the printed wiring board has a wiring pattern-free area at the end of the winding start that is longer than the inner circumference of the coil body. This is thought to cause problems such as insufficient rigidity at the innermost circumference of the coil body or failure to form a cylindrical shape when wound around the core material. As a result, the cross-sectional shape of the coil body is thought to become elliptical. If such an elliptical coil body is used in a motor, motor performance is thought to be reduced. Furthermore, it is thought that the cross-sectional shape of the coil body is more likely to become elliptical when the space factor of the coil wiring is high or the outer diameter of the coil body is 50 mm or less.

[0005] The present invention relates to a coil substrate for a motor, the coil substrate having a flexible substrate having a first surface and a second surface opposite to the first surface, and a plurality of coil wires arranged along the longitudinal direction of the flexible substrate, wherein one end of the coil substrate is a winding start portion, and the coil substrate is formed into a substantially cylindrical shape, the motor coil substrate comprising a coil wire formed region where the coil wire is formed on at least one of the first surface and the second surface of the coil substrate, and a coil wire non-formed region where the coil wire is not formed on either the first surface or the second surface of the coil substrate, a first region R1 is arranged from one end of the coil substrate, and a second region R2 is arranged adjacent to the first region R1, the first region R1 is arranged as the coil wire non-formed region, and the second region R2 is arranged as the coil wire formed region, and the longitudinal length L1 of the coil wire non-formed region and the circumferential length C of the inner circumferential surface of the motor coil substrate satisfy the relationship of Equation 1: 1 / 3≦L1 / C<1 Equation 1

[0006] The coil substrate of the present invention is formed into a motor coil substrate by being wound into a cylindrical shape around a core material. In this case, if the non-coil wiring region at the winding start end of the coil substrate is too short, the distance from the vicinity of the winding start end to the conductor layer also becomes short. As a result, the coil substrate cannot be properly wound around the core material at the winding start, and the innermost layer does not become cylindrical, but becomes elliptical. As a result, the cross-sectional shape of the motor coil substrate may become elliptical. On the other hand, if the non-coil wiring region at the winding start end of the coil substrate is too long (e.g., longer than the inner periphery length of the motor coil substrate), the rigidity of the innermost periphery of the motor coil substrate may become insufficient, and the cross-sectional shape of the motor coil substrate may become elliptical. If a motor coil substrate with an elliptical shape is used in a motor, it is believed that motor performance will be reduced.

[0007] Furthermore, it is believed that when the space factor of the coil wiring in the motor coil substrate increases or the diameter of the motor coil substrate decreases, the cross-sectional shape becomes more likely to be elliptical. Furthermore, when the space factor of the coil wiring is high and the diameter of the motor coil substrate decreases, the cross-sectional shape becomes more likely to be elliptical, and when manufacturing a motor coil substrate using a core material using a semi-automatic or automatic machine, it is believed that this control becomes more difficult. For this reason, even in motor coil substrates where the space factor of the coil wiring is high or the diameter of the motor coil substrate decreases, it is required that the cross-sectional shape does not become elliptical.

[0008] In the motor coil substrate of the present invention, the relationship between the length L1 of the coil wiring non-forming region and the length C of the inner peripheral surface of the motor coil substrate is 1 / 3≦L1 / C. This prevents the coil wiring non-forming region at the winding start end of the coil substrate from becoming too short. For example, when the coil wiring consists of three phases, U, V, and W, the length of the coil wiring non-forming region can be ensured to be at least the length of the coil wiring for one phase. Therefore, the coil substrate can be wound smoothly around the core material at the winding start. Furthermore, by satisfying L1 / C<1, the coil wiring non-forming region at the winding start end of the coil substrate can be prevented from becoming too long, thereby ensuring the rigidity of the inner peripheral surface of the motor coil substrate. As a result, the cross-sectional shape of the motor coil substrate can be made to be a perfect circle. When the motor coil substrate with a perfect circle shape is housed in a motor housing, the gap between the housing and the substrate becomes uniform, ensuring motor performance.

[0009] Motor coil substrates are designed with a circular cross-sectional shape to ensure that the coil wiring is spaced at regular intervals. Therefore, when installed in a motor, the distance between the coil wiring of the motor coil substrate and the magnet is constant regardless of its position. As a result, the magnetic force generated by the coil wiring is constant. Maintaining a constant magnetic force contributes to the motor's torque and ensures motor performance. However, if the cross-sectional shape of a motor coil substrate were elliptical, when installed in a motor, the coil wiring would have portions where the distance between the magnet and the coil wiring is not constant. Therefore, the magnetic force generated by the coil wiring would be inconsistent in some areas. As a result, the motor's torque would not reach the specified value due to the inconsistent magnetic force of the coil wiring, and motor performance would not be ensured.

[0010] In the motor coil substrate of the present invention, the coil wiring forms a half turn with the first coil wiring on the first surface and a half turn with the second coil wiring on the second surface, and the first coil wiring and the second coil wiring are connected by a through hole or a via hole.

[0011] In the motor coil substrate of the present invention, a coil is formed by electrically connecting a half turn of the first coil wiring on the first surface and a half turn of the second coil wiring on the second surface via a through hole or a via hole. A motor coil substrate having a perfectly circular cross section can be formed using a coil substrate having half-turn coil wiring formed on each of the first and second surfaces. Furthermore, by forming the coil wiring in half turns, the space factor of the coil wiring can be increased. Furthermore, by forming the coil wiring in half turns, even if the space factor of the coil wiring is increased, the coil substrate can be wound cylindrically even if the cross-sectional diameter of the motor coil substrate is 50 mm or less.

[0012] In the motor coil substrate of the present invention, the coil wiring forms a spiral with the first coil wiring on the first surface and a spiral with the second coil wiring on the second surface, and the first coil wiring and the second coil wiring are connected by a through hole or a via hole.

[0013] In the motor coil substrate of the present invention, a coil is formed by electrically connecting a spiral of first coil wiring on the first surface and a spiral of second coil wiring on the second surface via a through hole or a via hole. A motor coil substrate having a perfectly circular cross section can be formed by using a coil substrate having spiral coil wiring formed on the first surface or the second surface.

[0014] In the motor coil substrate of the present invention, it is preferable that the space factor of the coil wiring of the coil substrate exceeds 50%. When the space factor of the coil wiring exceeds 50%, the magnetic force generated by the coil wiring is increased, contributing to the motor torque and stabilizing the motor performance. In the present invention, even when the space factor of the coil wiring exceeds 50%, it is easy to wind the motor coil substrate into a cylindrical shape.

[0015] The motor coil substrate of the present invention preferably has a cross-sectional diameter of 50 mm or less. By making the cross-sectional diameter of the motor coil substrate 50 mm or less, it becomes possible to apply the motor coil substrate to small motors. In the present invention, even if the cross-sectional diameter is 50 mm or less, it is easy to wind the motor coil substrate into a cylindrical shape.

[0016] In the motor coil substrate of the present invention, the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and not more than 0.3 mm. In the present invention, a motor coil substrate having a cross-sectional shape of a perfect circle can be formed.

[0017] In the motor coil substrate of the present invention, the third region R3 is disposed adjacent to the second region R2, and the third region R3 is a region where no coil wiring is formed.

[0018] In the motor coil substrate of the present invention, the coil wiring non-forming region of the third region R3 is disposed so as to correspond to the coil wiring non-forming region of the first region R1.

[0019] The motor of the present invention is formed by providing one of the motor coil substrate and the magnet on the rotor and the other on the stator. By forming a motor using a motor coil substrate with a perfect circular shape, a motor that can ensure motor performance can be obtained.

[0020] The method for manufacturing a motor coil substrate of the present invention is a method for manufacturing a motor coil substrate in which the coil substrate is formed into a substantially cylindrical shape and includes a coil wiring formed region where coil wiring is formed on at least one of a first surface and a second surface of the coil substrate, and a coil wiring non-formed region where the coil wiring is not formed on either the first surface or the second surface of the coil substrate, the method comprising: preparing a coil substrate in which a first region R1 is arranged from one end of the coil substrate, a second region R2 is arranged adjacent to the first region R1, the first region R1 is the coil wiring non-formed region, and the second region R2 is the coil wiring formed region, a length L1 in the longitudinal direction of the coil wiring non-formed region and a length C in the circumferential direction of the inner peripheral surface of the motor coil substrate satisfy the relationship of Equation 1; and placing a core material on the end of the first region R1 of the coil substrate and winding the coil substrate to manufacture the motor coil substrate.

[0021] The manufacturing method of the motor coil substrate of the present invention makes it possible to form a motor coil substrate having a perfectly circular cross section. By forming a motor using the perfectly circular motor coil substrate, a motor that can ensure motor performance can be obtained.

[0022] FIG. 4 is a top view showing a coil substrate of an embodiment. FIG. 5 is a cross-sectional view taken along line II-II in FIGS. 1 and 3. FIG. 6 is a bottom view showing a coil substrate of an embodiment. FIG. 7 is a perspective view schematically showing a motor coil substrate using the coil substrate of an embodiment. FIG. 8 is a cross-sectional view showing a cross section perpendicular to the central axis of a motor coil substrate using the coil substrate of an embodiment. FIG. 9 is a cross-sectional view showing a cross section perpendicular to the central axis of a motor coil substrate using the coil substrate of a first comparative example. FIG. 10 is a cross-sectional view showing a cross section perpendicular to the central axis of a motor coil substrate using the coil substrate of a second comparative example. FIG. 11 is a cross-sectional view schematically showing a motor using the motor coil substrate of an embodiment. FIG. 12 is a top view showing a coil substrate of a modified example. FIG. 13 is a bottom view showing a coil substrate of a modified example. FIG. 14 is a diagram showing an example of a method for manufacturing a motor coil substrate.

[0023] [Embodiment] Fig. 1 is a top view showing a coil substrate 2 of an embodiment. Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1 and Fig. 3. Fig. 3 is a bottom view showing the coil substrate 2 of the embodiment.

[0024] As shown in Figures 1 to 3, 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, terminal connection wiring 45U, 45V, 45W, inter-coil connection wiring 50U, 50V, 50W, and inter-phase connection wiring 60U, 60V, 60W.

[0025] The flexible substrate 10 is a resin substrate having a first surface 10F and a second surface 10B opposite 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, a second side E2, a third side E3, and a fourth side E4. The first side E1 is a short side at one end of the flexible substrate 10 in the longitudinal direction (the direction of arrow LD in FIG. 1 ). The second side E2 is a short side at the other end of the flexible substrate 10 in the longitudinal direction. Both the first side E1 and the second side E2 are short sides extending in an orthogonal direction (the direction of arrow OD in FIG. 1 ) perpendicular to the longitudinal direction of the flexible substrate 10. The third side E3 and the fourth side E4 are long sides extending in the longitudinal direction of the flexible substrate 10. The flexible substrate 10 becomes the coil substrate 2 by forming coil wiring on it.

[0026] As shown in FIGS. 1 to 3 , the coil substrate 2 has a first region R1 located near one end of the coil substrate 2 in the longitudinal direction, a second region R2 located adjacent to the first region R1, and a third region R3 located adjacent to the second region R2 and near the other end of the coil substrate 2 in the longitudinal direction. As shown in FIG. 2 , the first region R1 is a non-coil wiring region where no coil wiring is formed on either the first surface 10F or the second surface 10B of the coil substrate 2. The second region R2 is a coil wiring region where coil wiring is formed on at least one of the first surface 10F or the second surface 10B of the coil substrate 2. The third region R3 is a non-coil wiring region where no coil wiring is formed on either the first surface 10F or the second surface 10B of the coil substrate 2. The first region R1 includes a first edge E1, and the third region R3 includes a second edge E2. The coil wiring formation region refers to a region where coil wiring is formed on either the first surface 10F or the second surface 10B, or on both surfaces.

[0027] The U-phase terminal 40U, the V-phase terminal 40V, and the W-phase terminal 40W are formed on the third side E3 of the coil substrate 2. The U-phase terminal 40U, the V-phase terminal 40V, and the W-phase terminal 40W are arranged within the second region R2. As shown in FIGS. 1 and 3 , the U-phase terminal 40U is connected to the starting end 20US of the U-phase coil 20U by a terminal connecting wiring 45U. The U-phase terminal 40U is also connected to the ending end 20WE of the W-phase coil 20W via an inter-phase connecting wiring 60W. The V-phase terminal 40V is connected to the starting end 20VS of the V-phase coil 20V by a terminal connecting wiring 45V. The V-phase terminal 40V is also connected to the ending end 20UE of the U-phase coil 20U via an inter-phase connecting wiring 60U. The W-phase terminal 40W is connected to the starting end 20WS of the W-phase coil 20W by a terminal connecting wiring 45W. Furthermore, W-phase terminal 40W is connected to termination 20VE of V-phase coil 20V via interphase connecting wiring 60V. That is, in the embodiment, U-phase coil 20U, V-phase coil 20V, and W-phase coil 20W are delta-connected. Note that, in other examples, U-phase coil 20U, V-phase coil 20V, and W-phase coil 20W may be Y-connected or may be connected in some other way.

[0028] Terminal connecting wiring 45U connects the coil wiring of U-phase coil 20U to U-phase terminal 40U, terminal connecting wiring 45V connects the coil wiring of V-phase coil 20V to V-phase terminal 40V, and terminal connecting wiring 45W connects the coil wiring of W-phase coil 20W to W-phase terminal 40W. Interphase connecting wiring 60U connects the coil wiring of U-phase coil 20U to V-phase terminal 40V, interphase connecting wiring 60V connects the coil wiring of V-phase coil 20V to W-phase terminal 40W, and interphase connecting wiring 60W connects the coil wiring of W-phase coil 20W to U-phase terminal 40U.

[0029] The U-phase coil 20U, the V-phase coil 20V, and the W-phase coil 20W respectively constitute the U-phase, the V-phase, and the W-phase of the three-phase motor.

[0030] 1 and 3, the starting end 20US and the ending end 20UE of U-phase coil 20U are disposed within second region R2. U-phase coil 20U includes eight coils 31U, 32U, 33U, 34U, 35U, 36U, 37U, and 38U. The eight coils 31U to 38U are arranged in this order along the longitudinal direction of flexible substrate 10 from starting end 20US toward ending end 20UE of U-phase coil 20U. The eight coils 31U to 38U are connected to each other by inter-coil connection wiring 50U.

[0031] Each of the eight coils 31U to 38U is formed by forming a first coil wiring, which constitutes half of one turn, on the first surface 10F side, and a second coil wiring, which constitutes the remaining half turn, on the second surface 10B side, with adjacent turns being staggered. The first coil wiring and the second coil wiring are electrically connected by through holes or via holes formed in the flexible substrate 10.

[0032] The winding start positions (starting ends) of the first coil 31U, the third coil 33U, the fifth coil 35U, and the seventh coil 37U from the starting end 20US of the U-phase coil 20U are arranged on the first surface 10F, and the winding end positions (terminating ends) are arranged on the second surface 10B. When the flexible substrate 10 is viewed from the first surface 10F side, the coils 31U, 33U, 35U, and 37U are wound counterclockwise.

[0033] Meanwhile, the winding start positions (starting ends) of the second coil 32U, the fourth coil 34U, the sixth coil 36U, and the eighth coil 38U from the starting end 20US of the U-phase coil 20U are disposed on the second surface 10B, and the winding end positions (terminating ends) are disposed on the first surface 10F. When the flexible substrate 10 is viewed from the first surface 10F side, the coils 32U, 34U, 36U, and 38U are wound clockwise.

[0034] 1, 2, and 3, a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 31U overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 32U via the flexible substrate 10. Furthermore, a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 32U overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 33U. Furthermore, a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 33U overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 34U. Furthermore, a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 34U overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 35U. Furthermore, a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 35U overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 36U. Further, a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 36U overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 37U. Further, a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 37U overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 38U.

[0035] 1 and 3, the coil-to-coil connection wiring 50U connecting coil 31U and coil 32U, the coil-to-coil connection wiring 50U connecting coil 33U and coil 34U, the coil-to-coil connection wiring 50U connecting coil 35U and coil 36U, and the coil-to-coil connection wiring 50U connecting coil 37U and coil 38U are arranged on the second surface 10B. On the other hand, the coil-to-coil connection wiring 50U connecting coil 32U and coil 33U, the coil-to-coil connection wiring 50U connecting coil 34U and coil 35U, and the coil-to-coil connection wiring 50U connecting coil 36U and coil 37U are arranged on the first surface 10F. The U-phase terminal 40U, the terminal connection wiring 45U, and the interphase connection wiring 60U are arranged on the first surface 10F.

[0036] 1 and 3, the starting end 20VS and the ending end 20VE of the V-phase coil 20V are disposed within the second region R2. The V-phase coil 20V includes eight coils 31V, 32V, 33V, 34V, 35V, 36V, 37V, and 38V. The eight coils 31V to 38V are arranged in this order along the longitudinal direction of the flexible substrate 10 from the starting end 20VS of the V-phase coil 20V toward the ending end 20VE. The eight coils 31V to 38V are connected to each other by inter-coil connection wiring 50V.

[0037] Each of the eight coils 31V to 38V is formed by forming a first coil wiring, which constitutes half of one turn, on the first surface 10F side, and a second coil wiring, which constitutes the remaining half turn, on the second surface 10B side, with adjacent turns being staggered. The first coil wiring and the second coil wiring are electrically connected by through holes or via holes formed in the flexible substrate 10.

[0038] The winding start positions (starting ends) of the first coil 31V, the third coil 33V, the fifth coil 35V, and the seventh coil 37V from the starting end 20VS of the V-phase coil 20V are arranged on the first surface 10F, and the winding end positions (terminating ends) are arranged on the second surface 10B. When the flexible substrate 10 is viewed from the first surface 10F side, the coils 31V, 33V, 35V, and 37V are wound counterclockwise.

[0039] Meanwhile, the winding start positions (starting ends) of the second coil 32V, the fourth coil 34V, the sixth coil 36V, and the eighth coil 38V from the starting end 20VS of the V-phase coil 20V are disposed on the second surface 10B, and the winding end positions (terminating ends) are disposed on the first surface 10F. When the flexible substrate 10 is viewed from the first surface 10F side, the coils 32V, 34V, 36V, and 38V are wound clockwise.

[0040] 1, 2, and 3, a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the coil 31V overlaps a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the adjacent coil 32V via the flexible substrate 10. Furthermore, a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the coil 32V overlaps a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the adjacent coil 33V. Furthermore, a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the coil 33V overlaps a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the adjacent coil 34V. Furthermore, a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the coil 34V overlaps a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the adjacent coil 35V. Furthermore, a portion of the wiring (first coil wiring) on ​​the first surface 10F side of coil 35V overlaps a portion of the wiring (second coil wiring) on ​​the second surface 10B side of adjacent coil 36V. Further, a portion of the wiring (first coil wiring) on ​​the first surface 10F side of coil 36V overlaps a portion of the wiring (second coil wiring) on ​​the second surface 10B side of adjacent coil 37V. Further, a portion of the wiring (first coil wiring) on ​​the first surface 10F side of coil 37V overlaps a portion of the wiring (second coil wiring) on ​​the second surface 10B side of adjacent coil 38V.

[0041] 1 and 3, the coil-to-coil connection wiring 50V connecting coil 31V and coil 32V, the coil-to-coil connection wiring 50V connecting coil 33V and coil 34V, the coil-to-coil connection wiring 50V connecting coil 35V and coil 36V, and the coil-to-coil connection wiring 50V connecting coil 37V and coil 38V are arranged on the second surface 10B. On the other hand, the coil-to-coil connection wiring 50V connecting coil 32V and coil 33V, the coil-to-coil connection wiring 50V connecting coil 34V and coil 35V, and the coil-to-coil connection wiring 50V connecting coil 36V and coil 37V are arranged on the first surface 10F. The V-phase terminal 40V, the terminal connection wiring 45V, and the interphase connection wiring 60V are arranged on the first surface 10F.

[0042] 1 and 3, a starting end 20WS and a terminal end 20WE of W-phase coil 20W are disposed within second region R2. W-phase coil 20W includes eight coils 31W, 32W, 33W, 34W, 35W, 36W, 37W, and 38W. The eight coils 31W to 38W are arranged in this order along the longitudinal direction of flexible substrate 10 from starting end 20WS toward terminal end 20WE of W-phase coil 20W. The eight coils 31W to 38W are connected to each other by inter-coil connection wiring 50W.

[0043] Each of the eight coils 31W to 38W is formed by forming a first coil wiring, which constitutes half of one turn, on the first surface 10F side, and a second coil wiring, which constitutes the remaining half turn, on the second surface 10B side, with adjacent turns being staggered. The first coil wiring and the second coil wiring are electrically connected by through holes or via holes formed in the flexible substrate 10.

[0044] The winding start positions (starting ends) of the first coil 31W, the third coil 33W, the fifth coil 35W, and the seventh coil 37W from the starting end 20WS of the W-phase coil 20W are arranged on the first surface 10F, and the winding end positions (terminating ends) are arranged on the second surface 10B. When the flexible substrate 10 is viewed from the first surface 10F side, the coils 31W, 33W, 35W, and 37W are wound counterclockwise.

[0045] Meanwhile, the winding start positions (starting ends) of the second coil 32W, the fourth coil 34W, the sixth coil 36W, and the eighth coil 38W from the starting end 20WS of the W-phase coil 20W are disposed on the second surface 10B, and the winding end positions (terminating ends) are disposed on the first surface 10F. When the flexible substrate 10 is viewed from the first surface 10F side, the coils 32W, 34W, 36W, and 38W are wound clockwise.

[0046] 1, 2, and 3, a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 31W overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 32W via the flexible substrate 10. Also, a portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 32W overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 33W. A portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 33W overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 34W. A portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 34W overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 35W. A portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 35W overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 36W. A portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 36W overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 37W. A portion of the wiring (second coil wiring) on ​​the second surface 10B side of the coil 37W overlaps a portion of the wiring (first coil wiring) on ​​the first surface 10F side of the adjacent coil 38W.

[0047] 1 and 3, the coil-to-coil connection wiring 50W connecting coil 31W and coil 32W, the coil-to-coil connection wiring 50W connecting coil 33W and coil 34W, the coil-to-coil connection wiring 50W connecting coil 35W and coil 36W, and the coil-to-coil connection wiring 50W connecting coil 37W and coil 38W are arranged on the second surface 10B. On the other hand, the coil-to-coil connection wiring 50W connecting coil 32W and coil 33W, the coil-to-coil connection wiring 50W connecting coil 34W and coil 35W, and the coil-to-coil connection wiring 50W connecting coil 36W and coil 37W are arranged on the first surface 10F. The W-phase terminal 40W, the terminal connection wiring 45W, and the interphase connection wiring 60W are arranged on the first surface 10F.

[0048] As shown in FIGS. 1 and 3 , in this embodiment, the wiring of each coil 20U, 20V, and 20W is arranged in a hexagonal shape. In other examples, the wiring of each coil 20U, 20V, and 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, or a polygon with more than two sides. The wiring arrangement of all coils does not necessarily have to be the same; the wiring arrangement may differ between coils. The number of turns of each coil wiring is not particularly limited, but may be one or more turns, preferably three to seven turns. The coil wiring is formed by forming a half turn of the first coil wiring on the first surface 10F and a half turn of the second coil wiring on the second surface 10B, and connecting the first coil wiring and the second coil wiring via a through hole or a via hole. A half turn refers to half of the coil wiring. Alternatively, a quarter turn may be formed on the first surface 10F and a quarter turn on the second surface 10B, and these may be connected by a through hole or a via hole, forming a half turn in total on the first surface 10F or the second surface 10B. Furthermore, the coil wiring may be disposed on either the first surface 10F or the second surface 10B. In this case, the coil wiring on the first surface 10F and the coil wiring on the second surface 10B may overlap entirely, partially, or not at all.

[0049] Although not shown, the first and second coil wirings of the U-phase coil 20U, V-phase coil 20V, and W-phase coil 20W, the terminal connection wirings 45U, 45V, and 45W, the inter-coil connection wirings 50U, 50V, and 50W, and the inter-phase connection wirings 60U, 60V, and 60W are covered with an insulating layer. The insulating layer may be formed to conform to the wiring, or it may cover the circuit and fill the spaces between adjacent wirings. The insulating layer prevents the wiring from being exposed, maintaining insulation. The method for forming the insulating layer is not particularly limited, but it can be formed by printing a liquid resin or by electro-deposition of a resin. An example of the resin is polyimide.

[0050] [Motor Coil Substrate] FIG. 4 is a perspective view schematically illustrating a motor coil substrate 550 using the coil substrate 2 (FIGS. 1 to 3) of the embodiment. As shown in FIG. 11, a core material CM is placed on the end of the first region R1 of the coil substrate 2 of the embodiment, and the coil substrate 2 is wound cylindrically around the core material CM to form a motor coil substrate 550. The material of the core material CM is not particularly limited, but metal is preferably used. When the coil substrate 2 is wound cylindrically, the winding starts at the first edge E1 of the flexible substrate 10 and ends at the second edge E2 of the flexible substrate 10, and the coil substrate 2 is wound multiple times around a central axis AX (FIGS. 5 to 7) extending parallel to the first edge E1. The number of times the coil substrate 2 is wound is not particularly limited, but is preferably between two and ten times. When the coil substrate 2 is wound cylindrically, the first surface 10F of the flexible substrate 10 is positioned on the outer periphery, and the second surface 10B is positioned on the inner periphery. When the coil substrate 2 is wound into a cylindrical shape, the first surface 10F of the flexible substrate 10 may be disposed on the inner periphery side, and the second surface 10B may be disposed on the outer periphery side. Winding the coil substrate 2 into a cylindrical shape also means forming the coil substrate 2 into a cylinder.

[0051] The coil substrate 2 is wound such that coils 31U, 32U, 33U, and 34U overlap with coils 35U, 36U, 37U, and 38U in the radial direction. Similarly, the coil substrate 2 is wound such that coils 38V, 37V, 36V, and 35V overlap with coils 34V, 33V, 32V, and 31V in the radial direction. Similarly, the coil substrate 2 is wound such that coils 31W, 32W, 33W, and 34W overlap with coils 35W, 36W, 37W, and 38W in the radial direction. As a result, the coil substrate 2 is wound such that the U phase, V phase, and W phase are repeated four times per turn. Note that the coil substrate 2 may be configured such that the U phase, V phase, and W phase are repeated one to three times or five or more times per turn.

[0052] Fig. 5 is a cross-sectional view showing a cross section perpendicular to the central axis AX of a motor coil substrate 550 using the coil substrate 2 of the embodiment (Figs. 1 to 3). Fig. 6 is a cross-sectional view showing a cross section perpendicular to the central axis AX of a motor coil substrate 550A using the coil substrate 2A of the first comparative example. Fig. 7 is a cross-sectional view showing a cross section perpendicular to the central axis AX of a motor coil substrate 550B using the second proportional coil substrate 2B. In Figs. 5 to 7, the vertically hatched portion indicates the first region R1, the grid-hatched portion indicates the second region R2, and the horizontally hatched portion indicates the third region R3.

[0053] 5, L1 is the longitudinal length of the first region R1 in the coil substrate 2 (the circumferential length of the first region R1 in the motor coil substrate 550), and C is the circumferential length of the inner circumferential surface of the motor coil substrate 550 (the circumferential length of the outer circumferential surface of the cylindrical core material CM). The length C is π × DI, where DI is the inner diameter of the motor coil substrate 550 (the diameter of the cylindrical core material CM). As shown in FIG. 5, in the coil substrate 2 of this embodiment, the length L1 and the length C satisfy the relationship of Equation 1: 1 / 3≦L1 / C<1 (Equation 1)

[0054] When L1 / C is 1, the angular range of the first region R1 is 360° (one revolution) with respect to the imaginary line VL, which is a straight line connecting the start of winding (first side E1) of the coil substrate and the central axis AX, which is the center of the cylindrical shape of the coil substrate 2. When L1 / C is 1 / 3, the angular range of the first region R1 is 120° with respect to the imaginary line VL. FIG. 5 shows an example in which the length L1 is approximately 1 1 / 12 of the length C. Note that the length L1 of the first region R1 may be other than 1 1 / 12 of the length C.

[0055] As described above, the second region R2 is wound in two layers by radially overlapping coils 31U-34U and coils 35U-38U, coils 38V-35V and coils 34V-31V, and coils 31W-34W and coils 35W-38W. Note that, because a portion of the second coil wiring of coils 38U, 31V, and 38W on one end radially overlaps a portion of the first coil wiring of coils 31U, 38V, and 31W on the other end, the second region R2 is wound in three layers in the angle range corresponding to this overlapping portion.

[0056] The length L3 of the third region R3 corresponds to approximately 1 1 / 12 of the length LO in FIG. 5, and is disposed on the outermost periphery. The length L3 of the third region R3 may be other than 1 1 / 12 of the length LO. L3 is the longitudinal length of the third region R3 in the coil substrate 2 (the circumferential length of the third region R3 in the motor coil substrate 550), and LO is the circumferential length of the outer surface of the motor coil substrate 550. The length LO is π × DO, where DO is the outer diameter of the motor coil substrate 550. As shown in FIG. 5, in the coil substrate 2 of this embodiment, the length L3 and the length LO preferably satisfy the relationship of Equation 2: 1 / 3≦L3 / LO<1 (Equation 2)

[0057] Furthermore, it is preferable that the arrangement of the third region R3 corresponds to the arrangement of the first region R1. By arranging the third region R3 so that the arrangement of the first region R1 corresponds to the arrangement of the third region R3, when viewed in a cross section of the motor coil substrate 550, the coil wiring non-forming region becomes equal, the thickness direction becomes constant, and the shape becomes close to a perfect circle.

[0058] Motor coil substrates are designed to have a nearly perfect circular or perfect circular cross-sectional shape so that the coil wiring is spaced at regular intervals. Therefore, when housed in a motor, the distance between the coil wiring of the motor coil substrate and the magnet is constant regardless of its position. As a result, the magnetic force generated by the coil wiring is constant. Maintaining a constant magnetic force contributes to the motor's torque and ensures motor performance. However, if the cross-sectional shape of a motor coil substrate is elliptical, when housed in a motor, the coil wiring will have portions where the distance from the magnet is not constant. Therefore, the magnetic force generated by the coil wiring will be inconsistent in some areas. As a result, it is believed that the motor's torque will not reach the specified value due to the portions of the coil wiring that have inconsistent magnetic force, and that motor performance will not be ensured.

[0059] Here, a coil substrate with an increased coil wiring space factor may not be easily wound into a cylindrical shape using a core material CM. In particular, a coil substrate with a coil wiring space factor exceeding 50% is more likely to be difficult to wind into a cylindrical shape using a core material CM. Furthermore, a coil substrate in which a half turn of the first coil wiring and a half turn of the second coil wiring are connected by a through hole or a via hole has an increased coil wiring space factor, making it difficult to wind into a cylindrical shape using a core material CM. Therefore, a coil substrate consisting of a half turn of the first coil wiring and a half turn of the second coil wiring and having a coil wiring space factor exceeding 50% is difficult to wind into a cylindrical shape using a core material CM. Here, a coil substrate with a coil wiring space factor exceeding 50% is called a high-density coil substrate. Even when a motor coil substrate is formed using this high-density coil substrate, the length L1 of the coil wiring non-forming region of the high-density coil substrate and the circumferential length C of the inner peripheral surface of the motor coil substrate satisfy the relationship of Equation 1, thereby enabling the motor coil substrate to be formed into a cylindrical shape. 1 / 3≦L1 / C<1 (Equation 1) In this case, when forming a motor coil substrate by forming the high-density coil substrate into a cylindrical shape, the core material CM is used to facilitate cylindrical winding. In this case, the cross-sectional shape of the motor coil substrate becomes approximately or completely circular. After forming into a cylindrical shape, insulation is ensured on the inner peripheral surface. Furthermore, the coil wiring is less likely to be scratched. Furthermore, when manufacturing a motor coil substrate using the core material CM, it is believed that the cross-sectional shape of the motor coil substrate will be approximately or completely circular, even when the process is performed using semi-automatic or automatic machines. In addition, problems such as winding misalignment of the motor coil substrate are reduced, and the need for rewinding the coil substrate is suppressed.

[0060] Furthermore, when the cross-sectional diameter of a motor coil substrate is small, it becomes difficult to wind the coil substrate into a cylindrical shape using a core material CM. In particular, when the cross-sectional diameter of a motor coil substrate is 50 mm or less, it tends to become difficult to wind the coil substrate into a cylindrical shape using a core material CM. Furthermore, as the cross-sectional diameter becomes smaller, the frequency of rewinding increases. Here, a coil substrate with a cross-sectional diameter of 50 mm or less is referred to as a miniaturized coil substrate. Even when a motor coil substrate is formed using a miniaturized coil substrate, the motor coil substrate can be formed into a cylindrical shape by satisfying the relationship in Equation 1 between the length L1 of the coil wiring non-forming region of the miniaturized coil substrate and the circumferential length C of the inner peripheral surface of the motor coil substrate. 1 / 3≦L1 / C<1 (Equation 1) In this case, when forming a motor coil substrate using a miniaturized coil substrate into a cylindrical shape, it becomes easy to wind the motor coil substrate into a cylindrical shape using a core material CM. In this case, the cross-sectional shape of the motor coil substrate becomes approximately a perfect circle or a perfect circle. After forming into a cylindrical shape, insulation is ensured on the inner peripheral surface. Furthermore, the coil wiring is less likely to be scratched. Furthermore, when manufacturing a motor coil substrate using the core material CM, it is thought that the cross-sectional shape of the motor coil substrate will become approximately a perfect circle or a perfect circle even if semi-automatic or automatic machines are used. Furthermore, even if the cross-sectional diameter of the motor coil substrate is set to 30 mm or less, the cross-sectional shape will become approximately a perfect circle or a perfect circle.

[0061] In other words, to accommodate both high density and miniaturization of motor coil substrates, the length L1 of the coil wiring non-forming region of the coil substrate and the circumferential length C of the inner peripheral surface of the motor coil substrate must satisfy the relationship in Equation 1, allowing the motor coil substrate to be formed into a cylindrical shape. 1 / 3≦L1 / C<1 (Equation 1) In this case, when forming a motor coil substrate with a cylindrical shape to achieve high density and / or miniaturization, it is easy to wind the coil into a cylindrical shape using a core material CM. In this case, the cross-sectional shape of the motor coil substrate becomes approximately or completely circular. After forming the cylindrical shape, insulation is ensured on the inner peripheral surface. Furthermore, the coil wiring is less likely to be scratched. Furthermore, when manufacturing a motor coil substrate using the core material CM, the cross-sectional shape of the motor coil substrate becomes approximately or completely circular, even when using semi-automatic or automatic machinery, and it is believed that control for this is also easy. Here, "high density" refers to a coil wiring space factor of over 50% on the coil substrate, and "miniaturization" refers to a cross-sectional diameter of the motor coil substrate of 50 mm or less. The coil wiring space factor refers to the space factor of the coil wiring on the coil substrate. The coil wiring space factor is calculated as follows: coil wiring space factor = (sum of cross-sectional areas of conductor parts / coil cross-sectional area) x 100.

[0062] Furthermore, the cross-sectional shape of the motor coil substrate being nearly perfect circular or perfect circular means that 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 cylindricity of the outer peripheral surface is measured using a V-block measurement method. That is, the motor coil substrate is placed on a V-block, rotated once, and the difference in the direction perpendicular to the axis is measured at five different points, and the average value is calculated to measure the cylindricity of the outer peripheral surface OC.

[0063] As shown in Fig. 6, in the coil substrate 2A of the first comparative example, the length L1 of the coil wiring non-forming region and the circumferential length C of the inner peripheral surface of the motor coil substrate satisfy the relationship of Equation 3: 0≦L1 / C<1 / 3 (Equation 3) Fig. 6 shows an example in which the length L1 is approximately 1 / 8 of the length C (L1 / C = 1 / 8), i.e., the angular range of the first region R1 is approximately 45°. Note that the length L1 may be other than 1 / 8 of the length C as long as Equation 3 is satisfied. The second region R2 is configured in the same manner as in the embodiment, and the third region R3 has an angular range of approximately 90°.

[0064] In the motor coil substrate 550A of the first comparative example, the first region R1, which is the non-coil wiring region at the winding start end of the coil substrate 2A, is too short, resulting in high rigidity near the winding start end. This prevents the coil substrate 2A from being properly wound around the core material CM at the beginning of winding, potentially resulting in an elliptical cross-sectional shape of the motor coil substrate 550A. Specifically, when the coil substrate 2A is wound around the core material CM, the coil substrate 2A may not align with the core material CM and may float. Continued winding leads to an elliptical shape. Furthermore, high-density coil substrates or miniaturized coil substrates are more likely to align with the core material CM and float, resulting in an elliptical shape. In particular, as the diameter of the motor coil substrate 550A decreases, the cross-sectional shape tends to become elliptical, making it more difficult to apply to small motors. If the motor coil substrate 550A has an elliptical cross-sectional shape, when the motor coil substrate 550A is installed in a motor, the coil wiring will have portions with an inconsistent distance from the magnet. Therefore, the magnetic force obtained by the coil wiring is not uniform in some areas. As a result, it is thought that the motor torque does not reach a predetermined value due to the inconsistent magnetic force of the coil wiring, and motor performance cannot be ensured. Note that the motor coil substrate 550A of the first comparative example has a coil wiring space factor of 75%, a cross-sectional diameter of the motor coil substrate 550A of 10 mm, and a cylindricity of the outer peripheral surface of the motor coil substrate 550A of more than 0.3 mm (0.39 mm).

[0065] As shown in Fig. 7, in the coil substrate 2B of the second comparative example, the length L1 and the length C satisfy the relationship of Equation 4: 1≦L1 / C (Equation 4) Fig. 7 shows an example in which the length L1 is greater than the length C (L1 / C>1), i.e., the angular range of the first region R1 is approximately 200°. Note that the length L1 may also be approximately equal to the length C (L1 / C=1). The second region R2 is configured in the same manner as in the embodiment, and the third region R3 has an angular range of approximately 390°.

[0066] In the motor coil substrate 550B of the second comparative example, the first region R1, which is the non-coil wiring region at the winding start end of the coil substrate 2B, is too long. This may result in insufficient rigidity at the inner periphery of the motor coil substrate 550B, resulting in an elliptical cross-sectional shape. As a specific example, when the coil substrate 2B is wound around the core material CM, the non-coil wiring region of the coil substrate 2B is crushed or shifted, resulting in an elliptical cross-sectional shape if the winding continues. Furthermore, if there is an overlapping portion of the non-coil wiring region on the inner periphery of the motor coil substrate 550B, the overlapping portion will form a protrusion, resulting in an elliptical cross-sectional shape. When the motor coil substrate 550B has an elliptical cross-sectional shape, the coil wiring will have an inconsistent distance from the magnet when installed in a motor. This results in inconsistent magnetic force generated by the coil wiring. As a result, it is thought that the motor torque will not reach a predetermined value due to the portions of the coil wiring where the magnetic force is not constant, and motor performance will not be ensured. Note that, in the motor coil board 550B of one example of the second comparative example, the coil wiring space factor is 75%, the cross-sectional diameter of the motor coil board 550B is 10 mm, and the cylindricity of the outer peripheral surface of the motor coil board 550B exceeds 0.3 mm (0.38 mm).

[0067] In the coil substrate 2 of the embodiment, as described above, the relationship between the length L1 of the first region R1 (the region where no coil wiring is formed) and the length C of the inner periphery of the motor coil substrate 550 satisfies 1 / 3≦L1 / C. This prevents the first region R1 at the winding start end of the coil substrate 2 from becoming too short. Furthermore, when the coil wiring consists of three phases (U, V, and W), the length of the first region R1 can be ensured to be at least the length of the coil wiring for one phase. Therefore, the coil substrate 2 can be smoothly wound around the core material CM at the winding start. Furthermore, satisfying L1 / C<1 prevents the first region R1 at the winding start end of the coil substrate 2 from becoming too long, thereby ensuring the rigidity of the inner periphery of the motor coil substrate 550. The relationship 1 / 3≦L1 / C was also obtained through trial and error in winding using the core material CM. As a result, the cross-sectional shape of the motor coil substrate 550 can be made perfectly circular. The motor coil substrate 550 is designed to have a perfectly circular cross section so that the coil wiring is spaced at regular intervals. Therefore, when housed in a motor, the distance between the coil wiring of the motor coil substrate 550 and the magnet is constant at any position. As a result, the magnetic force obtained by the coil wiring is constant. Keeping the magnetic force constant contributes to the motor torque and ensures motor performance.

[0068] [Motor] FIG. 8 is a cross-sectional view schematically illustrating a motor 600 using the motor coil substrate 550 (FIGS. 4 and 5) according to an embodiment. The motor 600 is formed by providing one of the motor coil substrate 550 and the magnet 570 on a rotor 610 and the other on a stator 620. As shown in FIG. 8, the motor 600 is formed by placing the motor coil substrate 550 inside a yoke 560, and placing a rotating shaft 580 and a magnet 570 fixed to the rotating shaft 580 inside the motor coil substrate 550. The motor 600 according to this embodiment is a slotless motor. The magnet 570 and the rotating shaft 580 form the rotor 610, and the motor coil substrate 550 and the yoke 560 form the stator 620.

[0069] The motor coil substrate 550 is disposed inside a cylindrical yoke 560 (an example of a housing). 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.

[0070] In the embodiment, the magnet 570 is provided on the rotor 610, and the motor coil substrate 550 is provided on the stator 620, but this is not limiting. In another example, the magnet 570 may be provided on the stator, and the motor coil substrate 550 may be provided on the rotor. Furthermore, although the motor coil substrate 550 in the embodiment is used in a slotless motor, it may also be used in motors other than slotless motors.

[0071] [Effects of the Embodiments] As described above, the configurations of the coil substrate 2 (FIGS. 1 to 3), motor coil substrate 550 (FIGS. 4 and 5), and motor 600 (FIG. 8) of the embodiment have been described. As described above, the coil substrate 2 of the embodiment is wound cylindrically around a core material CM to form the motor coil substrate 550. In this case, if the first region R1, which is the non-coil wiring region at the winding start end of the coil substrate 2, is too short, the distance from the vicinity of the winding start end to the conductor layer will also be short. As a result, the coil substrate 2 cannot be wound properly around the core material CM at the winding start, and the innermost layer will not be cylindrical but will instead be elliptical. As a result, the cross-sectional shape of the motor coil substrate 550 may become elliptical. In particular, as the diameter of the motor coil substrate 550 becomes smaller, the cross-sectional shape becomes more likely to be elliptical. On the other hand, if the first region R1 is too long (for example, longer than the inner periphery of the motor coil substrate 550), the rigidity of the innermost periphery of the motor coil substrate 550 may become insufficient, and the cross section of the motor coil substrate 550 may become elliptical. If the motor coil substrate 550 having an elliptical shape is used in the motor 600, it is thought that the motor performance will deteriorate.

[0072] In the coil substrate 2 of this embodiment, the relationship between the length L1 of the first region R1 and the length C of the inner circumferential surface of the motor coil substrate 550 is 1 / 3≦L1 / C. This prevents the first region R1 at the winding start end of the coil substrate 2 from becoming too short. Furthermore, when the coil wiring consists of three phases (U, V, and W), the length of the first region R1 can be ensured to be at least the length of the coil wiring for one phase. Therefore, the coil substrate 2 can be properly wound around the core material CM at the winding start. Furthermore, by satisfying L1 / C<1, the first region R1 of the coil substrate 2 can be prevented from becoming too long, thereby ensuring the rigidity of the innermost periphery of the motor coil substrate 550. As a result, the cross-sectional shape of the motor coil substrate 550 can be made perfectly circular. When the motor coil substrate 550 with a perfectly circular shape is accommodated in the yoke 560 of the motor 600, the gap between the yoke 560 and the motor coil substrate 550 becomes uniform, ensuring motor performance.

[0073] In the coil substrate 2 of the embodiment, a coil is formed by electrically connecting a half turn of the first coil wiring on the first surface 10F of the flexible substrate 10 and a half turn of the second coil wiring on the second surface 10B via a through hole or a via hole. A motor coil substrate 550 having a perfectly circular cross section can be formed by using a coil substrate 2 in which half-turn coil wiring is formed on each of the first surface 10F and the second surface 10B.

[0074] In the coil substrate 2 of the embodiment, when the coil substrate is made cylindrical to achieve high density or small size, or both, and the motor coil substrate 550 is formed, it is easy to wind the coil substrate into a cylindrical shape using the core material CM. Furthermore, after forming the coil substrate into a cylindrical shape, insulation is ensured on the inner peripheral surface. Furthermore, the coil wiring is less likely to be scratched.

[0075] The motor coil substrate 550 of the embodiment can have a perfectly circular cross section. When the perfectly circular motor coil substrate 550 is housed in the yoke 560 of the motor 600, the gap between the yoke 560 and the motor coil substrate 550 becomes uniform, thereby improving motor performance.

[0076] The motor 600 of this embodiment is formed using a motor coil substrate 550 that has a perfect circular shape. This results in a high-performance motor 600. In one example embodiment, the relationship between the length L1 of the first region R1 and the length C of the inner circumferential surface of the motor coil substrate 550 is L1 / C = 0.917. The layout of the third region R3 corresponds to the layout of the first region R1. The space factor of the coil wiring is 75%, the cross-sectional diameter of the motor coil substrate 550 is 10 mm, and the cylindricity of the outer circumferential surface of the motor coil substrate 550 is 0.2 mm.

[0077] [Modification of the Embodiment] In a first modification of the embodiment, in addition to or instead of specifying the longitudinal length L1 of the first region R1, which is a coil wiring non-forming region at one longitudinal end, a longitudinal length L3 of the third region R3, which is a coil wiring non-forming region at the other longitudinal end, is specified. The length L3 is the longitudinal length of the third region R3 in the coil substrate 2 (the circumferential length of the third region R3 in the motor coil substrate 550), and the length LO is the circumferential length of the outer surface of the motor coil substrate 550. The length LO is π × DO, where DO is the outer diameter of the motor coil substrate 550. In the coil substrate 2 of the first modification, the length L3 and the length LO satisfy the relationship of Equation 5: 1 / 3≦L3 / LO<1 (Equation 5)

[0078] In the coil substrate 2 of the first modified example, as described above, the relationship between the length L3 of the third region R3 (the region where no coil wiring is formed) and the length LO of the outer peripheral surface of the motor coil substrate 550 is 1 / 3≦L3 / LO. This prevents the third region R3 at the end of the winding of the coil substrate 2 from becoming too short. Furthermore, when the coil wiring consists of three phases (U, V, and W), the length of the third region R3 can be ensured to be at least the length of the coil wiring for one phase. Therefore, the coil substrate 2 can be wound properly around the core material CM at the end of the winding. Furthermore, by satisfying L3 / LO<1, the third region R3 at the end of the winding of the coil substrate 2 can be prevented from becoming too long, thereby ensuring the rigidity of the outer periphery of the motor coil substrate 550. As a result, the cross-sectional shape of the motor coil substrate 550 can be made perfectly circular.

[0079] 9 and 10 show a second modified example of the embodiment. Fig. 9 is a top view showing a coil substrate 102 of the modified example. Fig. 10 is a bottom view showing the coil substrate 102 of the modified example.

[0080] 9 and 10 , coil substrate 102 includes flexible substrate 10, U-phase coil 20U, V-phase coil 20V, W-phase coil 20W, U-phase terminal 40U, V-phase terminal 40V, W-phase terminal 40W, terminal connecting wirings 45U, 45V, 45W, and inter-phase connecting wirings 60U, 60V, 60W. In the second modified example, coils 31U, 31V, 31W constituting U-phase coil 20U, V-phase coil 20V, and W-phase coil 20W form a spiral with first coil wiring on first surface 10F and form a spiral with second coil wiring on second surface 10B, and the first coil wiring and second coil wiring are connected by through holes TH or via holes VH. In addition, in Figures 9 and 10, only coils 31U, 31V, and 31W are shown as the coils that make up U-phase coil 20U, V-phase coil 20V, and W-phase coil 20W, but U-phase coil 20U, V-phase coil 20V, and W-phase coil 20W may be formed by multiple coils including coils 31U, 31V, and 31W.

[0081] 9 and 10 , U-phase terminal 40U, V-phase terminal 40V, W-phase terminal 40W, terminal connecting wiring 45U, 45V, 45W, first coil wiring of coils 31U, 31V, 31W, and a portion of interphase connecting wiring 60W on the terminal connecting wiring 45U side are formed on first surface 10F of flexible substrate 10. On the other hand, interphase connecting wiring 60U, 60V, second coil wiring of coils 31U, 31V, 31W, and a portion of interphase connecting wiring 60W on the coil 31W side are formed on second surface 10B of flexible substrate 10.

[0082] The first coil wiring on the first surface 10F constituting the coil 31U and the second coil wiring on the second surface 10B constituting the coil 31U are each formed in a spiral shape (a hexagonal spiral shape). The first coil wiring and the second coil wiring are overlapped via the flexible substrate 10, and the inner peripheral end of the first coil wiring and the inner peripheral end of the second coil wiring are connected via a through hole TH or a via hole VH. As shown in FIG. 9, the outer peripheral end of the first coil wiring of the coil 31U is connected to the U-phase terminal 40U via a terminal connecting wiring 45U. As shown in FIG. 10, the outer peripheral end of the second coil wiring of the coil 31U is connected to one end of the interphase connecting wiring 60U.

[0083] The first coil wiring on the first surface 10F constituting the coil 31V and the second coil wiring on the second surface 10B constituting the coil 31V are each formed in a spiral shape (a hexagonal spiral shape). The first coil wiring and the second coil wiring are overlapped via the flexible substrate 10, and the inner peripheral end of the first coil wiring and the inner peripheral end of the second coil wiring are connected via a through hole TH or a via hole VH. As shown in FIG. 9, the outer peripheral end of the first coil wiring of the coil 31V is connected to the V-phase terminal 40V via the terminal connection wiring 45V and to the other end of the interphase connecting wiring 60U via a through hole TH or a via hole VH. As shown in FIG. 10, the outer peripheral end of the second coil wiring of the coil 31V is connected to one end of the interphase connecting wiring 60V.

[0084] The first coil wiring on the first surface 10F constituting the coil 31W and the second coil wiring on the second surface 10B constituting the coil 31W are each formed in a spiral shape (a hexagonal spiral shape). The first coil wiring and the second coil wiring are overlapped via the flexible substrate 10, and the inner peripheral end of the first coil wiring and the inner peripheral end of the second coil wiring are connected via through holes TH or via holes VH. As shown in FIG. 9, the outer peripheral end of the first coil wiring of the coil 31W is connected to the W-phase terminal 40W via the terminal connecting wiring 45W and to the other end of the interphase connecting wiring 60V via the through holes TH or via holes VH. As shown in FIG. 10, the outer peripheral end of the second coil wiring of the coil 31W is connected to one end of the interphase connecting wiring 60W. The portion of the interphase connecting wiring 60W on the coil 31W side and the portion on the terminal connecting wiring 45U side are connected via the through holes TH or via holes VH.

[0085] 9 and 10 , the flexible substrate 10 has a first region R1 located near one end of the flexible substrate 10 in the longitudinal direction, a second region R2 located adjacent to the first region R1, and a third region R3 located adjacent to the second region R2 and near the other end of the flexible substrate 10 in the longitudinal direction. As shown in FIGS. 9 and 10 , the first region R1 is a non-coil wiring region where no coil wiring is formed on either the first surface 10F or the second surface 10B of the flexible substrate 10. The second region R2 is a coil wiring region where coil wiring is formed on at least one of the first surface 10F or the second surface 10B of the flexible substrate 10. The third region R3 is a non-coil wiring region where no coil wiring is formed on either the first surface 10F or the second surface 10B of the flexible substrate 10. The first region R1 includes a first edge E1, and the third region R3 includes a second edge E2.

[0086] 9 and 10 , in the modified example, the wiring of each of the coils 20U, 20V, and 20W is arranged in a hexagonal shape. In other examples, the wiring of each of the coils 20U, 20V, and 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, or a polygon with seven or more sides. Furthermore, the wiring arrangement shape of all the coils does not have to be the same, and the wiring arrangement shape may differ between the coils.

[0087] The coil substrate 102 of the modified example also has the same characteristics as the coil substrate 2 of the embodiment. Specifically, in the coil substrate 102, the relationship between the length L1 of the first region R1 and the length C of the inner circumferential surface of the motor coil substrate 550 using the coil substrate 102 is 1 / 3≦L1 / C. This prevents the first region R1 at the winding start end of the coil substrate 102 from becoming too short. Furthermore, when the coil wiring consists of three phases, U, V, and W, the length of the first region R1 can be ensured to be at least the length of the coil wiring for one phase. Therefore, the coil substrate 102 can be smoothly wound around the core material CM at the winding start. Furthermore, by satisfying L1 / C<1, the first region R1 of the coil substrate 102 can be prevented from becoming too long, thereby ensuring the rigidity of the inner circumferential surface of the motor coil substrate 550. As a result, the cross-sectional shape of the motor coil substrate 550 can be made perfectly circular. When the motor coil substrate 550 having a perfect circular shape is housed in the yoke 560 of the motor 600, the gap between the yoke 560 and the motor coil substrate 550 becomes uniform, thereby improving the motor performance.

[0088] In addition, in the coil substrate 102 of the modified example, the spiral of the first coil wiring on the first surface 10F and the spiral of the second coil wiring on the second surface 10B are electrically connected via through holes or via holes to form a coil. A motor coil substrate 550 having a perfectly circular cross-sectional shape can be formed using a coil substrate 102 having spiral coil wiring formed on the first surface 10F or the second surface 10B. As an example of a modified embodiment, the relationship between the length L1 of the first region R1 and the length C of the inner circumferential surface of the motor coil substrate 550 is L1 / C = 0.917. The arrangement of the third region R3 corresponds to the arrangement of the first region R1. The space factor of the coil wiring is 55%, the cross-sectional diameter of the motor coil substrate 550 is 10 mm, and the cylindricity of the outer circumferential surface of the motor coil substrate 550 is 0.2 mm.

[0089] 2 Coil substrate 10 Flexible substrate (resin substrate) 10B Second surface 10F First surface 20U U-phase coil (coil wiring) 20V V-phase coil (coil wiring) 20W W-phase coil (coil wiring) 102 Coil substrate 550 Motor coil substrate 570 Magnet 600 Motor 610 Rotor 620 Stator E1 First side E2 Second side L1 Length L3 Length C Length LO Length R1 First region (coil wiring non-formed region) R2 Second region (coil wiring formed region) R3 Third region (coil wiring non-formed region)

Claims

1. A motor coil substrate comprising: a flexible substrate having a first surface and a second surface opposite to the first surface; and a plurality of coil wires arranged along the longitudinal direction of the flexible substrate, wherein one end of the coil substrate is a winding start portion; and the coil substrate is formed into a substantially cylindrical shape, and comprises a coil wire forming region where the coil wire is formed on at least one of the first surface and the second surface of the coil substrate; and a coil wire non-forming region where the coil wire is not formed on either the first surface or the second surface of the coil substrate; a first region R1 is arranged from one end of the coil substrate; and a second region R2 is arranged adjacent to the first region R1; the coil wire non-forming region is arranged in the first region R1; and the coil wire forming region is arranged in the second region R2; and the longitudinal length L1 of the coil wire non-forming region and the circumferential length C of the inner peripheral surface of the motor coil substrate satisfy the relationship of Equation 1: 1 / 3≦L1 / C<1 Equation 1 2. A motor coil substrate according to claim 1, wherein the coil wiring forms a half turn with the first coil wiring on the first surface and a half turn with the second coil wiring on the second surface, and the first coil wiring and the second coil wiring are connected by through holes or via holes.

3. A motor coil substrate according to claim 1, wherein the coil wiring forms a spiral with the first coil wiring on the first surface and a spiral with the second coil wiring on the second surface, and the first coil wiring and the second coil wiring are connected by through holes or via holes.

4. A motor coil substrate according to claim 1, wherein the space factor of the coil wiring of said coil substrate exceeds 50%.

5. A motor coil substrate according to claim 1, wherein the cross-sectional diameter of said motor coil substrate is 50 mm or less.

6. A motor coil substrate according to claim 1, wherein the cylindricity of the outer peripheral surface of said motor coil substrate is greater than 0.0 mm and not more than 0.3 mm.

7. A motor coil substrate according to claim 1, wherein a third region R3 is disposed adjacent to the second region R2, and the coil wiring non-forming region is disposed in the third region R3.

8. A motor coil substrate according to claim 7, wherein the coil wiring non-forming region of the third region R3 is arranged to correspond to the coil wiring non-forming region of the first region R1.

9. A motor formed by providing one of the motor coil substrate and magnet of claim 1 on a rotor and the other on a stator.

10. A method for manufacturing a motor coil substrate, in which the coil substrate is formed into a substantially cylindrical shape and is composed of a coil wiring formed region where coil wiring is formed on at least one of a first surface and a second surface of the coil substrate, and a coil wiring non-formed region where the coil wiring is not formed on either the first surface or the second surface of the coil substrate, wherein a first region R1 is arranged from one end of the coil substrate, a second region R2 is arranged adjacent to the first region R1, the first region R1 is the coil wiring non-formed region, and the second region R2 is the coil wiring formed region, a coil substrate is prepared in which the longitudinal length L1 of the coil wiring non-formed region and the circumferential length C of the inner peripheral surface of the motor coil substrate satisfy the relationship of Equation 1, and a core material is placed on the end of the first region R1 of the coil substrate, and the coil substrate is manufactured by winding the coil substrate. 1 / 3≦L1 / C<1 Equation 1 11. A method for manufacturing a motor coil substrate according to claim 10, wherein the space factor of the coil wiring of the coil substrate exceeds 50%.

12. A method for manufacturing a motor coil substrate according to claim 10, wherein the diameter of the cross section of the motor coil substrate is 50 mm or less.

13. A method for manufacturing a motor coil substrate according to claim 10, wherein the cylindricity of the outer peripheral surface of the motor coil substrate is greater than 0.0 mm and not more than 0.3 mm.

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