Flexible circuit board, electric motor, and method for manufacturing a flexible circuit board

A flexible circuit board with alternating parallel wirings on both surfaces of an insulating sheet simplifies the manufacturing process and reduces weight by eliminating separate coil connections, enhancing magnetic force in electric motors.

JP7866447B2Active Publication Date: 2026-05-27HONDA MOTOR CO LTD
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
HONDA MOTOR CO LTD
Filing Date
2022-08-03
Publication Date
2026-05-27

AI Technical Summary

Technical Problem

Conventional stator configurations using flexible circuit boards for electric motors are heavy due to high coil density and complex manufacturing processes.

Method used

A flexible circuit board design with alternating parallel wirings on both surfaces of an insulating sheet, connected via via holes, forming continuous wirings that intersect to create electromagnetic coils, simplifying the manufacturing process and reducing weight.

Benefits of technology

The design reduces the weight and simplifies the manufacturing of electric motors by eliminating the need for separate coil connections and increasing coil density, enhancing magnetic force.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To provide a flexible circuit board that can achieve a reduction in the weight of an electric motor and simplification of manufacturing processes, and a method for manufacturing the same.SOLUTION: A flexible circuit board 1 comprises: a plurality of pieces of first wiring U1 and third wiring U3 that are formed alternately and in parallel to each other on a first surface 2 of an insulating sheet 10; a plurality of pieces of second wiring U2 and fourth wiring U4 that are formed alternately and in parallel to each other on a second surface 3 of the insulating sheet 10; first continuous wiring Us1 that connects the ends of the adjacent first wiring U1 and second wiring U2 with the insulating sheet 10 therebetween; second continuous wiring Us2 that connects the ends of the adjacent third wiring U3 and fourth wiring U4 with the insulating sheet 10 therebetween; and an inversion part Ut that connects the ends of the first continuous wiring Us1 and second continuous wiring Us2.SELECTED DRAWING: Figure 1
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Description

Technical Field

[0001] The present invention relates to a flexible circuit board, an electric motor, and a method for manufacturing a flexible circuit board.

Background Art

[0002] Conventionally, a technique for configuring a stator of a motor with a flexible circuit board has been known (see, for example, Patent Document 1). In Patent Document 1, a plurality of sheet coils in which coils are formed around each hole are wound in a roll type on a strip-shaped insulating film provided with a plurality of holes into which a stator core is inserted, and corresponding coils between the sheet coils are electrically connected to configure a stator. A manufacturing method is disclosed. Further, bending portions are set at equal intervals on an insulating sheet, and semicircular arc-shaped conductive patterns are alternately formed on each unit piece partitioned by the bending, so that they can be separated at the bending portions according to the number of turns and used (see, for example, Patent Document 2). department Further, an insulating layer, a first helical coil portion, a second helical coil portion, and a closed magnetic path are formed on a silicon substrate by a thin film forming technique, and the whole has a rectangular parallelepiped outer shape. A choke coil is known in which the first and second helical coil portions are formed such that the helical axes are substantially parallel to the substrate surface of the silicon substrate (see, for example, Patent Document 3). Further, a coreless motor is known in which parallel conductor line groups are formed on one side of a flexible substrate, two substrates in which metal conductor protrusion row groups are exposed at both ends of each parallel conductor line group are overlapped in opposite directions, and after joining the opposing metal conductor protrusion row groups, a cylindrical winding armature is used (see, for example, Patent Document 4). Further, parallel conductor A line group is formed, and two substrates in which metal conductor protrusion row groups are exposed at both ends of each parallel conductor line group are overlapped in opposite directions, and after joining the opposing metal conductor protrusion row groups, a coreless motor using a cylindrical winding armature is known (see, for example, Patent Document 4).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

[0004] While electric motors are required to be small and lightweight, the stator, a key component of electric motors, typically has a configuration in which coils are wound at high density. This configuration of the stator is a factor that increases the weight of the electric motor. Therefore, it is effective to reduce the weight of the electric motor by forming the coil pattern on a relatively lightweight flexible circuit board and constructing the stator from there. However, conventional stator configurations using flexible circuit boards have drawbacks, such as the need for processes to connect each coil formed on the flexible circuit board and to stack multiple flexible circuit boards with coil patterns formed on them, which complicates the manufacturing process and the structure of the stator. This application was filed in view of the above background, and aims to provide a flexible circuit board that enables weight reduction and simplification of the manufacturing process of electric motors, a method for manufacturing the same, and an electric motor composed of the flexible circuit board. [Means for solving the problem]

[0005] As a first embodiment for achieving the above objective, a plurality of first and third wirings are formed alternately in parallel along the longitudinal direction of a flexible strip-shaped insulating sheet on the first surface of the insulating sheet, and a plurality of second and fourth wirings are formed alternately in parallel along the longitudinal direction of the insulating sheet on the second surface of the insulating sheet, offset from the first and third wirings, and the ends of adjacent first and second wirings are connected via the insulating sheet to form a first continuous wiring in which a plurality of first and second wirings are alternately connected via the insulating sheet, and the ends of adjacent third and fourth wirings are connected via the insulating sheet. The wiring connection portion, by connecting thereto, forms a second continuous wiring in which a plurality of the third wirings and the fourth wirings are alternately connected via the insulating sheet; an external terminal connected to the first continuous wiring end, which is one end of the first continuous wiring; the second continuous wiring end, which is the other end of the first continuous wiring; and the second continuous wiring end, which is the end of the second continuous wiring on the side of the first continuous wiring end. The second continuous wiring end and the second continuous wiring end are formed on the same surface of the insulating sheet, the first surface and the second surface. The reverse connection portion is formed on the first surface and the second surface of the insulating sheet. surface A flexible circuit board is provided, which has a via hole formed on the surface facing the same surface and connects the second end of the first continuous wiring and the second end of the second continuous wiring through the insulating sheet.

[0006] In the above flexible circuit board, the first continuous wiring and the second continuous wiring have a chain-like shape intersecting with the insulating sheet, and the first continuous wiring and the second continuous wiring The wiring between adjacent intersections is The configuration may also be used to form an electromagnetic coil.

[0007] In the flexible circuit board described above, the wiring connection portion may be configured to connect the terminals of adjacent first and second wirings, and the terminals of adjacent third and fourth wirings, through via holes that penetrate the insulating sheet.

[0008] In the flexible circuit board described above, the external terminals and the inverting connection portion may be arranged on the same long side of the insulating sheet. In the above-described flexible circuit board, a plurality of wiring circuits comprising the first continuous wiring, the second continuous wiring, and the inversion connection portion may be provided, and the inversion connection portions of the plurality of wiring circuits may all be formed at the same end on the short side of the insulating sheet.

[0009] As a second embodiment for achieving the above objective, an electric motor comprising a stator formed by bending a flexible circuit board on which electromagnetic coil wiring is formed into a cylindrical shape, and a rotor arranged on the outer or inner circumference of the stator, wherein the flexible circuit board has a plurality of first and third wirings formed alternately in parallel in the longitudinal direction of the insulating sheet on the first surface of a flexible strip-shaped insulating sheet, a plurality of second and fourth wirings formed alternately in parallel in the longitudinal direction of the insulating sheet on the second surface of the insulating sheet, offset from the first and third wirings, and by connecting the ends of adjacent first and second wirings via the insulating sheet, a first continuous wiring is formed in which a plurality of first and second wirings are alternately connected via the insulating sheet, and the ends of adjacent third and fourth wirings are connected via the insulating sheet. As a result, the device has multiple phases of wiring connection parts that connect a wiring connection part in which a plurality of the third wirings and the fourth wirings are alternately connected via the insulating sheet to form a second continuous wiring, an external terminal connected to the first end of the first continuous wiring which is one end of the first continuous wiring, the second end of the first continuous wiring which is the other end of the first continuous wiring, and the second end of the second continuous wiring which is the end of the second continuous wiring on the side of the second end of the first continuous wiring, and the first continuous wiring and the second continuous wiring have a shape in which they intersect in a chain shape via the insulating sheet, the wiring between adjacent intersections of the first continuous wiring and the second continuous wiring each forms an electromagnetic coil of the slot of the stator, the second end of the first continuous wiring and the second end of the second continuous wiring are formed on the same surface of the insulating sheet, and the reverse connection part is formed on the first surface and the second surface of the insulating sheet surface An example is an electric motor having a via hole formed on the surface facing the same surface and connecting the second end of the first continuous wiring and the second end of the second continuous wiring through the insulating sheet.

[0010] As a third embodiment for achieving the above objective, the steps include: forming a plurality of first and third wirings alternately in parallel in a predetermined direction on the first surface of a flexible insulating sheet; forming a plurality of second and fourth wirings alternately in parallel in the predetermined direction on the second surface of the insulating sheet, offset from the first and third wirings; and forming a first continuous wiring in which a plurality of first and second wirings are alternately connected via the insulating sheet by connecting the ends of adjacent first and second wirings via the insulating sheet, thereby forming a first continuous wiring in which a plurality of first and second wirings are alternately connected via the insulating sheet, and forming a first continuous wiring in which a plurality of third wirings are alternately connected via the insulating sheet by connecting the ends of adjacent third and fourth wirings The process includes the steps of: forming a second continuous wiring in which the fourth wiring is alternately connected via the insulating sheet; forming an external terminal connected to the first end of the first continuous wiring, which is one end of the first continuous wiring; and forming an inverted connection portion connecting the second end of the first continuous wiring, which is the other end of the first continuous wiring, and the second end of the second continuous wiring, which is the end of the second continuous wiring on the side of the second end of the first continuous wiring, wherein the step of forming the first continuous wiring and the second continuous wiring is to form the second end of the first continuous wiring and the second end of the second continuous wiring on the same surface of the insulating sheet, and the step of forming the inverted connection portion is to form the first surface and the second surface of the insulating sheet surface One method for manufacturing a flexible circuit board is to form the inverted connection portion connecting the second end of the first continuous wiring and the second end of the second continuous wiring by via holes penetrating the insulating sheet on the surface facing the same surface. [Effects of the Invention]

[0011] The above-mentioned flexible circuit board makes it possible to reduce the weight of electric motors and simplify the manufacturing process. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is an explanatory diagram showing the configuration of the flexible circuit board that makes up the stator of an electric motor. [Figure 2] FIG. 2 is an explanatory diagram of an electric motor including a stator using a flexible circuit board. [Figure 3] FIG. 3 is an explanatory diagram showing the configuration of a flexible circuit board in which wiring forming an electromagnetic coil is doubled. [Figure 4] It is an explanatory diagram of the manufacturing process of a flexible circuit board.

Embodiments for Carrying Out the Invention

[0013] [1. Configuration of Flexible Circuit Board] Referring to FIGS. 1 and 2, the configuration of the flexible circuit board 1 of the present embodiment will be described. The flexible circuit board 1 is used as a component of the stator 70 of a three-phase brushless motor 50 (corresponding to the electric motor of the present disclosure) shown in FIG. 2. As shown in FIG. 1, the flexible circuit board 1 is configured by forming wiring of electromagnetic coils constituting slots for three phases of U, V, and W on both surfaces (the first surface 2 and the second surface 3) of an insulating sheet 10 having flexibility.

[0014] As shown in FIG. 2, by using a stator 70 in which the flexible circuit board 1 is bent in a cylindrical shape around the outer periphery of a rotor 60 to which a permanent magnet 61 is attached or embedded, it is possible to reduce the weight of the stator compared to a configuration in which a conductor is wound to form a coil like a general stator. Note that the stator 70 may be arranged on the inner peripheral side of the rotor 60.

[0015] Further, according to the flexible circuit board 1, it is easy to increase the arrangement density of the slots S of the stator 70. By increasing the arrangement density of the slots S, the magnetic path of the magnetic force generated in the electromagnetic coil of each slot S can be shortened, and the metal portion 51 of the stator 70 can be made thinner. Thereby, per unit volume of the brushless motor 50 weight can be reduced.

[0016] Referring to Figure 1, on the first surface 2 of the insulating sheet 10, a plurality of first wirings U1 (U1a, U1b, U1c, U1d) for forming a U-phase electromagnetic coil are formed in parallel and continuously in the X direction, which is the longitudinal direction of the insulating sheet 10. Also, on the second surface 3 of the insulating sheet 10, a plurality of second wirings U2 (U2a, U2b, U2c, U2d) for forming a U-phase electromagnetic coil are formed in parallel in the X direction of the insulating sheet 10.

[0017] The ends of adjacent first wiring U1 and second wiring U2 are electrically connected via via holes h through the insulating sheet 10. As a result, a first continuous wiring Us1 is formed in which the first wiring U1 and second wiring U2 are alternately connected through the insulating sheet 10 in the order of first wiring U1a → second wiring U2a → first wiring U1b → second wiring U2b → first wiring U1c → second wiring U2c → first wiring U1d → second wiring U2d.

[0018] Furthermore, on the first surface 2 of the insulating sheet 10, a plurality of third wirings U3 (U3a, U3b, U3c, U3d) for forming a U-phase electromagnetic coil are formed in parallel and continuously in the X direction of the insulating sheet 10. Also, on the second surface 3 of the insulating sheet 10, a plurality of fourth wirings U4 (U4a, U4b, U4c, U4d) for forming a U-phase electromagnetic coil are formed in parallel and continuously in the X direction of the insulating sheet 10.

[0019] The ends of the adjacent third wiring U3 and fourth wiring U4 are electrically connected via via holes h through the insulating sheet 10. As a result, a second continuous wiring Us2 is formed in which the third wiring U3 and the fourth wiring U4 are alternately connected through the insulating sheet 10 in the order of third wiring U3a → fourth wiring U4a → third wiring U3b → fourth wiring U4b → third wiring U3c → fourth wiring U4c → third wiring U3d → fourth wiring U4d.

[0020] One end of the first continuous wiring Us1 (the left end in Figure 1, corresponding to the first end of the first continuous wiring in this disclosure) is connected to the external terminal Uc of the U phase. The other end of the first continuous wiring Us1 (the right end in Figure 1, corresponding to the second end of the first continuous wiring in this disclosure) is connected to one end of the second continuous wiring Us2 (the right end in Figure 1, corresponding to the second end of the second continuous wiring in this disclosure) by an inversion section Ut, and is electrically connected. The other end of the second continuous wiring (the left end in Figure 1) is connected to a common connection section Cc. This connection forms a circuit that is electrically connected from the external terminal Uc → first continuous wiring Us1 → inversion section Ut → second continuous wiring Us2 → common connection section Cc.

[0021] Similarly, for the V phase, a first continuous wiring Vs1 is formed by alternately connecting multiple first wirings V1 (V1a, V1b, V1c, V1d) and second wirings V2 (V2a, V2b, V2c, V2d) via an insulating sheet 10. Furthermore, a second continuous wiring Vs2 is formed by alternately connecting multiple third wirings V3 (V3a, V3b, V3c, V3d) and fourth wirings V4 (V4a, V4b, V4c, V4d) via an insulating sheet 10. Finally, a circuit is formed that conducts from the external terminal Vc → first continuous wiring Vs1 → inversion section Vt → second continuous wiring Vs2 → common connection section Cc.

[0022] Similarly, for the W phase, a first continuous wiring Ws1 is formed by alternately connecting multiple first wirings W1 (W1a, W1b, W1c, W1d) and second wirings W2 (W2a, W2b, W2c, W2d) via an insulating sheet 10. In addition, multiple third wirings W3 (W3a, W3b, W3c, W3d) and a fourth wiring W4 ( W 4a, W 4b, W 4c, W 4d) is formed by alternately connecting the insulating sheet 10 to create a second continuous wiring Ws2. Then, a circuit is formed that is electrically connected from the external terminal Wc → first continuous wiring Ws1 → inversion section Wt → second continuous wiring W2s → common connection section Cc.

[0023] Thus, the flexible circuit board 1 has a chain-like intersecting circuit that constitutes electromagnetic coils for multiple slots for three phases U, V, and W. By supplying drive power from the motor drive circuit to the external terminals Uc, Vc, and Wc, a rotating magnetic field can be generated by the magnetic force generated in each slot.

[0024] In this case, unlike the stator of a typical brushless motor, the process of forming each slot with electromagnetic coils wound with conductors and the connection process to connect the coils are unnecessary, thus simplifying the stator manufacturing process. Furthermore, it is possible to improve the manufacturing quality of the brushless motor by avoiding defects in the process of connecting the electromagnetic coils in each slot, which can cause defects in the brushless motor. In Figure 1, an example is shown in which four first wirings U1, V1, W1 and four second wirings U2, V2, W2 are formed, but the number of stator slots can be arbitrarily set by increasing or decreasing the number of first wirings U1, V1, W1 and second wirings U2, V2, W2.

[0025] [2. Configuration with double wiring] Next, referring to Figure 3, we will explain an example of a configuration in which the first continuous wiring Us1 and the second continuous wiring Us2 corresponding to the U phase are duplicated. In Figure 3, for the sake of explanation, only the wiring for the U phase is shown, but the wiring for the V phase and W phase are similar.

[0026] In the example shown in Figure 3, two first continuous wirings Us1 (Us11, Us12) and two second continuous wirings Us2 (Us21, Us22) are formed. The first continuous wiring Us11 is formed by alternately connecting a plurality of first wirings U11 (U11a, U11b, U11c, U11d) formed on the first surface 2 of the insulating sheet 10 and a plurality of second wirings U21 (U21a, U21b, U21c, U21d) formed on the second surface 3 of the insulating sheet via via holes h.

[0027] Furthermore, the first second continuous wiring Us21 is formed by alternately connecting a plurality of third wirings U31 (U31a, U31b, U31c, U31d) formed on the second surface 3 of the insulating sheet 10 and a plurality of fourth wirings U41 (U41a, U41b, U41c, U41d) formed on the first surface 2 of the insulating sheet 10 via via holes h through the insulating sheet 10.

[0028] The second first continuous wiring Us12 is formed by alternately connecting a plurality of first wirings U12 (U12a, U12b, U12c, U12d) formed on the first surface 2 of the insulating sheet 10 and a plurality of second wirings U22 (U22a, U22b, U22c, U22d) formed on the second surface 3 of the insulating sheet 10 via via holes h through the insulating sheet 10.

[0029] Furthermore, the second continuous wiring Us22 is formed by alternately connecting a plurality of third wirings U32 (U32a, U32b, U32c, U32d) formed on the second surface 3 of the insulating sheet 10 and a fourth wiring U42 (U42a, U42b, U42c, U42d) formed on the first surface 2 of the insulating sheet 10 via via holes h through the insulating sheet 10.

[0030] One end of the first continuous wiring Us11 (the left end in Figure 3) is connected to the external terminal Uc, and the other end of the first continuous wiring Us11 (the right end in Figure 3) and one end of the second continuous wiring Us21 (the right end in Figure 3) are connected by the inversion section Ut1. Also, one end of the first continuous wiring Us12 (the left end in Figure 3) is connected to the other end of the second continuous wiring Us21 (the left end in Figure 3) and the relay section Ur. Furthermore, the other end of the first continuous wiring Us12 (the right end in Figure 3) and one end of the second continuous wiring Us22 (the right end in Figure 3) are connected and electrically connected by the inversion section Ut2. In addition, the other end of the second continuous wiring Us22 (the left end in Figure 3) is connected to the common connection section Cc.

[0031] This forms a circuit that conducts from the external terminal Uc → first continuous wiring Us11 → inversion section Ut1 → second continuous wiring Us21 → relay section Ur → first continuous wiring Us12 → inversion section Ut2 → second continuous wiring Us22 → common connection section Cc. Then, as shown by L in Figure 3, an electromagnetic coil is formed by double wiring at the intersection of the first continuous wiring Us11 and the second continuous wiring Us21, and at the intersection of the first continuous wiring Us12 and the second continuous wiring Us22.

[0032] In this way, by using double wiring, the magnetic force generated in the electromagnetic coils of the slots can be increased when the stator is constructed using the flexible circuit board 1. Note that the wiring may be tripled or more.

[0033] [3. Manufacturing of Flexible Circuit Boards] Referring to Figure 4, the manufacturing process of flexible circuit board 1 will be explained. The manufacturing process includes the following steps: (1) CCL (Cupper Clad Lamination, copper foil) preparation, (2) via hole drilling, (3) via plating, (4) dry film application, (5) exposure, (6) development, (7) etching, (8) dry film removal, (9) CL (Cover Lay) application and curing, (10) surface treatment, (11) outline cutting, and (12) inspection.

[0034] (1) CCL fabrication: Copper foils 12a and 12b are attached to both sides of the insulating sheet 10 (corresponding to the first side 2 and second side 3 in Figures 1 and 3) using adhesives 11a and 11b. (2) Via holes… Via holes 13a and 13b are made to allow electrical conductivity between copper foil 12a and copper foil 12b via the insulating sheet 10.

[0035] (3) Via plating: The via holes 13a, 13b and copper foils 12a, 12b are plated to make the copper foils 12a, 12b on both sides of the insulating sheet 10 electrically conductive. (4) Dry film application: Dry films 15a and 15b, which are made by processing photosensitive resin into a film, are applied to the first side 2 and the second side 3.

[0036] (5) Exposure... Negative films 16a and 16b with the circuit pattern drawn on them are placed on dry films 15a and 15b and exposed to ultraviolet light (UV) to harden the circuit parts. 17a to 17f are areas other than the circuit parts. In the example in Figure 1, the first wiring U1, V1, W1 and the fourth wiring U4, V4, W4 are drawn on the negative film 16b on the first side 2, and the second wiring U2, V2, W2 and the third wiring U3, V3, W3 are drawn on the negative film 16a on the second side 3.

[0037] (6) Development: Dissolve and remove the hardened portions of dry films 15a and 15b that correspond to areas other than the circuit pattern. (7) Etching... Dry etching using a reactive gas or plasma removes only the portions 19a to 19f from which the dry films 15a and 15b of the copper foils 12a and 12b and the plating 14a, 14b, and 14c have been removed.

[0038] (8) Dry film removal: Remove dry films 15a and 15b using a chemical solution. (9) CL bonding & curing... Coverlays 21a to 21d are pressed and bonded from the first surface 2 and second surface 3 sides to form an insulating layer. (10) Surface treatment: Gold plating is applied to the exposed parts of copper foil 12a and 12b (for rust prevention).

[0039] (11) Outline cutting...By cutting out the outline from the sheet, the flexible circuit board 1 shown in Figure 1 is completed. (12) Inspection... The flexible circuit board 1 is inspected for continuity, open circuits, short circuits, etc. In this case, the flexible circuit board 1 can be inspected on its own before being incorporated into the brushless motor 50. Therefore, unlike typical brushless motors in which the stator is assembled by incorporating electromagnetic coils wound with conductors, it is possible to avoid situations where faulty wiring in the stator is discovered during inspection after the brushless motor has been assembled, requiring replacement or repair of the stator.

[0040] [4. Other Embodiments] In the above embodiment, an example was shown in which the flexible circuit board 1 of this disclosure is used as a component of the stator of a brushless motor 50. However, the flexible circuit board 1 can also be used to configure the stator of other types of electric motors in which the stator is composed of electromagnetic coils.

[0041] Furthermore, the flexible circuit board disclosed herein can be applied to applications other than the stator of an electric motor. For example, the flexible circuit board disclosed herein may be used for noise suppression applications such as choke coils instead of electromagnetic coils. In addition, by forming reversing sections that reverse the direction of current flow in the wiring, as shown in Figure 1 (Ut, Vt, Wt), the flexible circuit board 1 can also be applied to applications that define the direction of current flow in the circuit board.

[0042] In the above embodiment, as shown in Figure 4, an example of manufacturing the flexible circuit board 1 by dry etching was described, but it may also be manufactured by wet etching. Furthermore, the flexible circuit board 1 may be manufactured using other manufacturing methods, such as an additive method in which copper is deposited only in the wiring portions by electroless plating, instead of a subtractive method by etching.

[0043] [5. Configurations supported by the above embodiment] The above embodiment is a specific example of the following configuration.

[0044] (Configuration 1) A flexible circuit board comprising: a first surface of a flexible strip-shaped insulating sheet having a plurality of first and third wirings formed alternately in parallel in the longitudinal direction of the insulating sheet; a second surface of the insulating sheet having a plurality of second and fourth wirings formed alternately in parallel in the longitudinal direction of the insulating sheet, offset from the first and third wirings; a wiring connection section that connects the ends of adjacent first and second wirings via the insulating sheet to form a first continuous wiring in which a plurality of first and second wirings are alternately connected via the insulating sheet, and connects the ends of adjacent third and fourth wirings via the insulating sheet to form a second continuous wiring in which a plurality of third and fourth wirings are alternately connected via the insulating sheet; an external terminal connected to the first continuous wiring end, which is one end of the first continuous wiring; the second continuous wiring end, which is the other end of the first continuous wiring; and the second continuous wiring end, which is the end of the second continuous wiring on the side of the first continuous wiring end. In the flexible circuit board of Configuration 1, the connections of the first, second, third, and fourth wirings formed on the insulating sheet are completed by the wiring connection section. Furthermore, a reversal connection section for reversing the direction of current flow between the first continuous wiring and the second continuous wiring, and an external terminal for supplying current to the first continuous wiring are also formed. Therefore, the manufacturing process can be simplified by eliminating the need for additional connection steps, and the circuit board is made lighter by increasing the density of wiring formed on the insulating sheet. Thus, by constructing an electric motor using the flexible circuit board of Configuration 1, it is possible to make the electric motor lighter and simplify the manufacturing process.

[0045] (Configuration 2) The flexible circuit board according to Configuration 1, wherein the first continuous wiring and the second continuous wiring have a chain-like shape intersecting with the insulating sheet, and the intersection of the first continuous wiring and the second continuous wiring forms an electromagnetic coil. According to the flexible circuit board of configuration 2, the magnetic field generated by energizing the first and second continuous wiring at the intersection allows the flexible circuit board to function as a stator with enhanced magnetic force.

[0046] (Configuration 3) The flexible circuit board according to Configuration 1 or Configuration 2, wherein the wiring connection portion connects the terminals of adjacent first and second wirings, and the terminals of adjacent third and fourth wirings, by via holes penetrating the insulating sheet. According to the flexible circuit board of configuration 3, by making connections using via holes, it becomes unnecessary to make separate connections between the terminals of the first and second wiring, and between the terminals of the third and fourth wiring, thereby simplifying the manufacturing of the flexible circuit board.

[0047] (Configuration 4) A flexible circuit board according to any one of Configurations 1 to 3, wherein the external terminal and the inverting connection portion are arranged on the same long side of the insulating sheet. According to the flexible circuit board of configuration 4, the arrangement efficiency of the external terminals and the inverting connection section can be improved, and the size of the flexible circuit board can be reduced.

[0048] (Configuration 5) An electric motor comprising a stator formed by bending a flexible circuit board on which electromagnetic coil wiring is formed into a cylindrical shape, and a rotor disposed on the outer or inner circumference of the stator, wherein the flexible circuit board has a plurality of first and third wirings formed alternately in parallel in the longitudinal direction of the insulating sheet on the first surface of a flexible strip-shaped insulating sheet, a plurality of second and fourth wirings formed alternately in parallel in the longitudinal direction of the insulating sheet on the second surface of the insulating sheet, offset from the first and third wirings, and a first continuous wiring is formed in which a plurality of first and second wirings are alternately connected via the insulating sheet by connecting the ends of adjacent first and second wirings via the insulating sheet. The motor comprises multiple phases of a wiring connection section that connects the ends of adjacent third and fourth wirings via the insulating sheet to form a second continuous wiring in which a plurality of third and fourth wirings are alternately connected via the insulating sheet, an external terminal connected to the first continuous wiring end which is one end of the first continuous wiring, the second continuous wiring end which is the other end of the first continuous wiring, and the second continuous wiring end which is the end of the second continuous wiring on the side of the first continuous wiring end which is the first continuous wiring end, and the first continuous wiring and the second continuous wiring have a chain-like crossing shape via the insulating sheet, and the crossings of the first continuous wiring and the second continuous wiring form the electromagnetic coils of the stator slots. According to the electric motor of configuration 5, since the stator circuit wiring is formed on the flexible circuit board, the process of constructing the stator by incorporating coils wound with conductors and the inspection of the assembled stator are eliminated, thereby simplifying the electric motor manufacturing process. Furthermore, by constructing the stator using a flexible circuit board, the electric motor can be made lighter.

[0049] (Configuration 6) A method for manufacturing a flexible circuit board, comprising the steps of: forming a plurality of first and third wirings on a first surface of a flexible insulating sheet, arranged alternately in parallel in a predetermined direction; forming a plurality of second and fourth wirings on a second surface of the insulating sheet, arranged alternately in parallel in the predetermined direction and offset from the first and third wirings; forming a first continuous wiring in which a plurality of first and second wirings are alternately connected via the insulating sheet by connecting the ends of adjacent first and second wirings via the insulating sheet, and forming a second continuous wiring in which a plurality of third and fourth wirings are alternately connected via the insulating sheet by connecting the ends of adjacent third and fourth wirings via the insulating sheet; forming an external terminal connected to the first continuous wiring end, which is one end of the first continuous wiring; and forming a reverse connection portion that connects the second continuous wiring end, which is the other end of the first continuous wiring, and the second continuous wiring end, which is the end of the second continuous wiring on the side of the first continuous wiring end. By implementing the manufacturing method of configuration 6, the flexible circuit board of configuration 1 can be manufactured. [Explanation of Symbols]

[0050] 1... Flexible circuit board, 2... First side of insulating sheet, 3... Second side of insulating sheet, 10 insulating sheets, U1 (U1a~U1d)... First wiring of U phase, V1 (V1a~V1d)... First wiring of V phase, W1 (W1a~W1d)... First wiring of W phase, U2 (U2a~U2d)... Second wiring of U phase, V2 (V2a~V2d)... Second wiring of V phase, W2 (W2a~W2d)... Second wiring of W phase, U3 (U3a~U3d)... Third wiring of U phase, V3 ( V3a~V3d)...Third wiring of the V phase, W3(W3a~W3d)...Third wiring of the W phase, U4(U4a~U4d)...Fourth wiring of the U phase, Us1...First continuous wiring of the U phase, Vs1...First continuous wiring of the V phase, Ws1...First continuous wiring of the W phase, Us2...Second continuous wiring of the U phase, Vs2...Second continuous wiring of the V phase, Ws2...Second continuous wiring of the W phase, Ut...Inverting section of the U phase, Vt...Inverting section of the V phase, Wt...Inverting section of the W phase, Uc...External terminal of the U phase, Vc...External terminal of the V phase, Wc...External terminal of the W phase, Cc... Common connection section, U11 (U11a~U11d), U12 (U12a~U12d)... Double first wiring of the U phase, U21 (U21a~U21d), U22 (U22a~U22d)... Double second wiring of the U phase, Us11, Us12... Double first continuous wiring of the U phase, Us21, Us22... Double second continuous wiring of the U phase, Ut1, Ut2... Double reversing section of the U phase, 50... Brushless motor (electric motor), 51... Metal part, 60... Rotor, 61... Permanent magnet, 70... Stator.

Claims

1. On the first surface of a flexible, strip-shaped insulating sheet, a plurality of first and third wirings are formed alternately in parallel in the longitudinal direction of the insulating sheet, On the second surface of the insulating sheet, a plurality of second and fourth wirings are formed alternately in parallel in the longitudinal direction of the insulating sheet, offset from the first and third wirings, A wiring connection section that connects the ends of adjacent first and second wirings via the insulating sheet to form a first continuous wiring configuration in which a plurality of first and second wirings are alternately connected via the insulating sheet, and connects the ends of adjacent third and fourth wirings via the insulating sheet to form a second continuous wiring configuration in which a plurality of third and fourth wirings are alternately connected via the insulating sheet, An external terminal connected to the first end of the first continuous wiring, which is one end of the first continuous wiring, The device comprises a reversing connector that connects the second end of the first continuous wiring, which is the other end of the first continuous wiring, and the second end of the second continuous wiring, which is the end of the second continuous wiring on the side of the second end of the first continuous wiring, The second end of the first continuous wiring and the second end of the second continuous wiring are formed on the same surface of the first and second surfaces of the insulating sheet. The inverted connection portion is formed on the surface of the insulating sheet facing the same surface, between the first and second surfaces, and connects the second end of the first continuous wiring and the second end of the second continuous wiring by via holes penetrating the insulating sheet. Flexible circuit board.

2. The first continuous wiring and the second continuous wiring have a chain-like crossing configuration via the insulating sheet, and the wiring between adjacent intersections of the first continuous wiring and the second continuous wiring each forms an electromagnetic coil. The flexible circuit board according to claim 1.

3. The wiring connection section connects the terminals of adjacent first and second wirings, and the terminals of adjacent third and fourth wirings, through via holes that penetrate the insulating sheet. A flexible circuit board according to claim 1 or claim 2.

4. The external terminal and the inversion connection portion are arranged on the same long side of the insulating sheet. A flexible circuit board according to claim 1 or claim 2.

5. The wiring circuit comprises a plurality of the first continuous wiring, the second continuous wiring, and the inverting connection section, The inverted connection portions of the multiple wiring circuits are all formed at the same end on the short side of the insulating sheet. A flexible circuit board according to claim 1 or claim 2.

6. An electric motor comprising a stator formed by bending a flexible circuit board on which electromagnetic coil wiring is formed into a cylindrical shape, and a rotor arranged on the outer or inner circumference of the stator, The aforementioned flexible circuit board is On the first surface of a flexible, strip-shaped insulating sheet, a plurality of first and third wirings are formed alternately in parallel in the longitudinal direction of the insulating sheet, On the second surface of the insulating sheet, a plurality of second and fourth wirings are formed alternately in parallel in the longitudinal direction of the insulating sheet, offset from the first and third wirings, A wiring connection section that connects the ends of adjacent first and second wirings via the insulating sheet to form a first continuous wiring configuration in which a plurality of first and second wirings are alternately connected via the insulating sheet, and connects the ends of adjacent third and fourth wirings via the insulating sheet to form a second continuous wiring configuration in which a plurality of third and fourth wirings are alternately connected via the insulating sheet, An external terminal connected to the first end of the first continuous wiring, which is one end of the first continuous wiring, An inverting connector is provided to connect the second end of the first continuous wiring, which is the other end of the first continuous wiring, and the second end of the second continuous wiring, which is the end of the second continuous wiring on the side of the second end of the first continuous wiring. Equipped with multiple phases, The first continuous wiring and the second continuous wiring have a chain-like crossing shape via the insulating sheet, and the wiring between adjacent intersections of the first continuous wiring and the second continuous wiring each forms an electromagnetic coil in the slot of the stator. The second end of the first continuous wiring and the second end of the second continuous wiring are formed on the same surface of the first and second surfaces of the insulating sheet. The inverted connection portion is formed on the surface of the insulating sheet facing the same surface, between the first and second surfaces, and connects the second end of the first continuous wiring and the second end of the second continuous wiring by via holes penetrating the insulating sheet. Electric motor.

7. A step of forming a plurality of first and third wirings on the first surface of a flexible insulating sheet, which are arranged alternately in parallel in a predetermined direction, A step of forming a plurality of second and fourth wirings on the second surface of the insulating sheet, arranged alternately in parallel in the predetermined direction and offset from the first and third wirings, The process involves connecting the ends of adjacent first and second wirings via the insulating sheet to form a first continuous wiring in which a plurality of first and second wirings are alternately connected via the insulating sheet, and connecting the ends of adjacent third and fourth wirings via the insulating sheet to form a second continuous wiring in which a plurality of third and fourth wirings are alternately connected via the insulating sheet, A step of forming an external terminal connected to the first end of the first continuous wiring, which is one end of the first continuous wiring; The process includes the step of forming an inverted connection portion that connects the second end of the first continuous wiring, which is the other end of the first continuous wiring, and the second end of the second continuous wiring, which is the end of the second continuous wiring on the side of the second end of the first continuous wiring, The step of forming the first continuous wiring and the second continuous wiring involves forming the second end of the first continuous wiring and the second end of the second continuous wiring on the same surface of the first and second surfaces of the insulating sheet. The step of forming the inverted connection portion involves forming the inverted connection portion on the surface of the insulating sheet facing the same surface, of the first and second surfaces, by via holes penetrating the insulating sheet, thereby connecting the second end of the first continuous wiring and the second end of the second continuous wiring. A method for manufacturing flexible circuit boards.