Stator manufacturing method and rotary electric machine

Abstract

To provide a method of manufacturing a stator capable of improving uniformity of an adhesive when a flexible circuit board is stuck to a stator core.SOLUTION: The method of manufacturing the stator includes an attaching step of attaching the flexible circuit board 1 to the inner peripheral surface of the stator core 51 by applying the room temperature curing adhesive 80 to at least one of the inner peripheral surface of the stator core 51 and the outer peripheral surface of the flexible circuit board 1, and a pressurizing and curing step of curing the adhesive 80 while maintaining a state in which a pressing force from the inside to the outside of the stator core 51 is applied to the adhesive 80 between the stator core 51 and the flexible circuit board 1 by a magnetic force generated between the stator core 51 and the pressurizing jig 100 by magnetically attaching the plate-shaped pressurizing jig 100 formed of a permanent magnet to the inner peripheral surface of the stator core 51 to which the flexible circuit board 1 is attached by the attaching step along the circumferential direction of the stator core 51.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a stator and a rotating electric machine. [Background technology]

[0002] BACKGROUND ART Conventionally, there is known a technique for constructing a stator of a motor by attaching a flexible circuit board on which a coil pattern is formed to the inner diameter surface of a cylindrical stator yoke (see, for example, Patent Documents 1 to 4). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 3-65041 [Patent Document 2] Japanese Patent Application Publication No. 4-299040 [Patent Document 3] Japanese Patent Application Publication No. 9-46992 [Patent Document 4] Japanese Patent Application Publication No. 10-248222 Summary of the Invention [Problem to be solved by the invention]

[0004] Rotating electric machines, especially motors, are required to be small, lightweight, and have high output efficiency. The stator, a key component of a rotating electric machine, is made up of densely wound coils, and the stator is a factor that increases the weight of the rotating electric machine. Therefore, as in the background art, constructing a stator using a flexible circuit board in which a wiring pattern serving as a coil is formed by printing on a resin film is effective in reducing the weight of a rotating electrical machine. However, when a stator is constructed by attaching a flexible circuit board to a stator core, the flexibility of the flexible circuit board makes it difficult to uniformly control the thickness of the adhesive used to secure the flexible circuit board to the stator core, and there is the disadvantage that variations in the inner diameter dimensions of the stator result in reduced motor efficiency. The present application has been made in view of the above background, and aims to provide a method for manufacturing a stator that can improve the uniformity of adhesive when attaching a flexible circuit board on which coil wiring is formed to a stator core, and a rotating electric machine equipped with such a stator. [Means for solving the problem]

[0005] As a first aspect for achieving the above object, there is a method for manufacturing a stator for a rotating electric machine by attaching a strip-shaped flexible circuit board having coil wiring formed thereon in a cylindrically bent state to the inner peripheral surface of a cylindrical stator core made of a magnetic material, the method including: an attachment process for applying a room temperature curing adhesive to at least one of the inner peripheral surface of the stator core and the outer peripheral surface of the flexible circuit board to attach the flexible circuit board to the inner peripheral surface of the stator core; and a pressure curing process for magnetically attaching a plate-shaped pressure jig formed by a permanent magnet to the inner peripheral surface of the stator core to which the flexible circuit board has been attached in the attachment process along the circumferential direction of the stator core, thereby hardening the adhesive between the stator core and the flexible circuit board by maintaining a state in which a pressure is applied from the inside to the outside of the stator core by a magnetic force generated between the stator core and the pressure jig.

[0006] In the above-mentioned stator manufacturing method, the pressing jig may consist of a plurality of sub-pressing jigs, and in the pressure hardening process, the plurality of sub-pressing jigs may be arranged circumferentially around the stator core and magnetically attached to the inner surface of the stator core.

[0007] In the above-described method for manufacturing a stator, the interval between adjacently arranged sub-pressure jigs may be configured to be less than one-third of the interval between the flexible circuit board fixed to the inner surface of the stator core with the adhesive after the pressure curing process is completed, and a rotor arranged on the inner side of the flexible circuit board.

[0008] In the above-described method for manufacturing a stator, the pressing jig may be made of a flexible ferromagnetic material.

[0009] In the above-described method for manufacturing a stator, the magnetic attraction range of the pressing jig to the stator core in the pressure hardening process and the magnetic force of the pressing jig may be set under control conditions such that the thickness distribution of the adhesive between the stator core and the flexible circuit board becomes 15±5 μm as the adhesive hardens in the pressure hardening process.

[0010] The above-described method for manufacturing a stator may also include an adhesive removing step of removing the adhesive that has protruded from the end of the stator core in the pressure hardening step before hardening of the adhesive is completed.

[0011] A second aspect for achieving the above object is a rotating electric machine equipped with a stator configured by bending a strip-shaped flexible circuit board having coil wiring onto the inner surface of a cylindrical stator core made of a magnetic material into a cylindrical shape and attaching it to the inner surface with a room temperature curing adhesive, and the thickness distribution of the adhesive between the stator core and the flexible circuit board is 15±5 μm.

[0012] In the above-mentioned rotating electric machine, the flexible circuit board may include a flexible, band-shaped insulating sheet and a predetermined number of coil wirings for multiple phases formed extending in the longitudinal direction of the insulating sheet and arranged in parallel at intervals, and may be configured to have a reinforcing wiring formed in the space of the insulating sheet between the short-side ends of the insulating sheet of the coil wiring on at least one of the first and second surfaces of the insulating sheet and conductive to one of the short-side ends of the insulating sheet of the adjacent coil wiring and extending in the longitudinal direction of the insulating sheet on the other end side.

[0013] In the above-mentioned rotating electric machine, the flexible circuit board may comprise a flexible, band-shaped insulating sheet, and a predetermined number of coil wirings for multiple phases that are formed extending in the longitudinal direction of the insulating sheet and arranged in parallel at intervals, and may also be configured to have a positioning protrusion formed on the short end of the insulating sheet. [Effects of the Invention]

[0014] The above-described method for manufacturing a stator can improve the uniformity of the adhesive when attaching a flexible circuit board on which coil wiring is formed to a stator core. The above-described rotating electric machine can improve the efficiency of the rotating electric machine by including a stator in which the uniformity of the adhesive when attaching a flexible circuit board on which coil wiring is formed to a stator core is improved. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is an explanatory diagram of a motor equipped with a stator made of a flexible circuit board. [Figure 2] FIG. 2 is an explanatory diagram showing the configuration of the flexible circuit board shown in FIG. [Figure 3] FIG. 3 is an explanatory diagram of the steps of the method for manufacturing the stator. [Figure 4] FIG. 4 is an explanatory diagram of the pressure hardening step. [Figure 5]FIG. 5 is an explanatory diagram of how the pressing jig is used. [Figure 6] FIG. 6 is an explanatory diagram of a first example of a configuration in which reinforcing wiring is formed on a flexible circuit board. [Figure 7] FIG. 7 is an explanatory diagram of a second example of a configuration in which reinforcing wiring is formed on a flexible circuit board. [Figure 8] FIG. 8 is an explanatory diagram of a third example of a configuration in which reinforcing wiring is formed on a flexible circuit board. [Figure 9] FIG. 9 is an explanatory diagram of a configuration in which positioning projections are formed on a flexible circuit board. DETAILED DESCRIPTION OF THE INVENTION

[0016] [1. Flexible circuit board and motor configuration] 1 and 2, a motor 50 (corresponding to a rotating electric machine of the present disclosure) including a stator 70 manufactured by the stator manufacturing method of this embodiment, and the configuration of a flexible circuit board 1 that constitutes the stator 70 will be described. Note that the rotating electric machine in which the flexible circuit board 1 is used may be a generator or the like in addition to a motor (electric motor). The configurations of the flexible circuit board 1 and motor 50 are similar to those of the flexible circuit board and motor described in Japanese Patent Laid-Open Publication No. 2024-21472, and are manufactured by the same process. For ease of explanation, FIG. 1 shows a simplified circuit configuration of the flexible circuit board described in the above publication.

[0017] As shown in FIG. 1, the motor 50 is configured with a stator 70, which is a flexible circuit board 1 bent into a cylindrical shape and arranged on the outside of a rotor 60 to which a permanent magnet 61 is attached or embedded. The flexible circuit board 1, which will be described in detail later, is configured by arranging a first sub-circuit board 2a and a second sub-circuit board 2b. By configuring the stator using the flexible circuit board 1 in this way, it is possible to reduce the weight of the stator compared to a typical stator configured to form a coil by winding a conductor wire. Note that the stator 70 may also be configured to be arranged on the inner periphery of the rotor 60.

[0018] Furthermore, the flexible circuit board 1 makes it easy to increase the arrangement density of the slots in the stator 70, and increasing the arrangement density of the slots shortens the magnetic path of the magnetic force generated in the electromagnetic coil of each slot, allowing the stator core 51 to be made thinner. This makes it possible to reduce the weight per volume of the motor 50. The outer circumferential side 51a of the stator core 51 is made of a non-magnetic material (such as an Al material), and the inner circumferential side 51b (back yoke) of the stator core 51 is made of a magnetic material (such as an Fe material, which is a soft magnetic material).

[0019] 2, the flexible circuit board 1 is configured by arranging a first sub-circuit board 2a and a second sub-circuit board 2b in the longitudinal direction of the first sub-circuit board 2a and the second sub-circuit board 2b (the longitudinal direction of the insulating sheet 10a constituting the first sub-circuit board 2a and the insulating sheet 10b constituting the second sub-circuit board 2b). In the following description, the longitudinal direction of the first sub-circuit board 2a and the second sub-circuit board 2b is referred to as the X direction. Furthermore, the lateral direction of the first sub-circuit board 2a and the second sub-circuit board 2b (the lateral direction of the insulating sheet 10a constituting the first sub-circuit board 2a and the insulating sheet 10b constituting the second sub-circuit board 2b) is referred to as the Y direction.

[0020] The first sub-circuit board 2a includes a flexible, strip-shaped insulating sheet 10a extending in the left-right direction of the figure, three coil wirings 31a, 32a, 33a (corresponding to the predetermined number of the present invention) formed by connecting multiple partial wirings formed on each of the two opposing main surfaces (first surface 11a, second surface 12a) of the insulating sheet 10a at their ends in the Y direction via vias v, and a connection portion 20a having connection terminals 21a, 22a, 23a to which each of the coil wirings 31a, 32a, 33a is individually connected.

[0021] The three coil wirings 31a, 32a, and 33a cross each other in a chain shape without being electrically connected to each other. In Fig. 1, the wiring (conductor pattern) formed on the first surface 11a (front surface) is shown by a solid line, and the wiring formed on the second surface 12a (back surface) is shown by a dashed line. Similarly, in Figs. 6, 7, 8, and 9 described below, the wiring formed on the illustrated front surface is shown by a solid line, and the wiring formed on the back surface is shown by a dashed line.

[0022] Of the two sides of insulating sheet 10a extending in the X direction, the upper side in the figure is referred to as long side 13a, and the lower side is referred to as long side 14a. Of the two sides of insulating sheet 10a extending in the Y direction, the right side in the figure is referred to as short side 15a, and the left side is referred to as short side 16a. In first sub-circuit board 2a, connection portion 20a is located at the end of short side 16a in the X direction (corresponding to the first longitudinal end in this disclosure).

[0023] In the first sub-circuit board 2a, the connection between the connection portion 20a and the external circuit 90 that supplies drive currents for the U, V, and W phases is set as follows: (connection terminal 21a, connection terminal 22a, connection terminal 23a) → (U phase, V phase, W phase). As a result, a coil current flows from the left to the right in the figure as shown in A2a, generating a rotating magnetic field that moves from the left to the right in the figure as shown in A1a. A1a corresponds to the predetermined direction in this disclosure.

[0024] The second sub-circuit board 2b is the first sub-circuit board 2a with the first surface 11a and the second surface 12a inverted around the axis E in the Y direction, and like the first sub-circuit board 2a, it is equipped with an insulating sheet 10b, coil wiring 31b, 32b, 33b formed on the insulating sheet 10b, and a connection portion 20b.

[0025] For the second sub-circuit board 2b, of the two sides of the insulating sheet 10b extending in the X direction, the upper side in the figure is referred to as the long side 13b, and the lower side is referred to as the long side 14b. Of the two sides of the insulating sheet 10b extending in the Y direction, the right side in the figure is referred to as the short side 15b, and the left side is referred to as the short side 16b.

[0026] In the second sub-circuit board 2b, the connection portion 20b is disposed at the end portion on the short side 16b side in the X direction (corresponding to the second longitudinal end portion in the present disclosure). The connection between the connection portion 20b and the external circuit 90 that supplies drive currents of U, V, and W phases is set as follows: (connection terminal 23b, connection terminal 22b, connection terminal 21b) → (U phase, V phase, W phase). As a result, as shown in A2b, a coil current flows from the right side (short side 15b side) to the left side (short side 16b side) of the figure, generating a rotating magnetic field that moves from the left side to the right side of the figure as shown in A1b.

[0027] That is, the direction of the rotating magnetic field generated by the first sub-circuit board 2a and the direction of the rotating magnetic field generated by the second sub-circuit board 2b are the same. This allows the rotor to rotate normally. Note that the connection between the connection terminals 21b, 22b, and 23b of the connection portion 20b of the second sub-circuit board 2b and the external terminals for the three phases U, V, and W may be configured as follows: (connection terminal 23b, connection terminal 22b, connection terminal 21b) → (W phase, U phase, V phase) or (connection terminal 23b, connection terminal 22b, connection terminal 21b) → (V phase, W phase, U phase). By using these connection configurations, the direction of the magnetic field generated by the second sub-circuit board 2b can be made the same as the direction of the magnetic field generated by the first sub-circuit board 2a.

[0028] Furthermore, the connection portion 20a of the first sub-circuit board 2a and the connection portion 20b of the second sub-circuit board 2b are adjacent to each other, and the first external terminal 71a connected to the connection portion 20a and the second external terminal 71b connected to the connection portion 20b can be arranged adjacent to each other. This allows the motor 50 and the external circuit 90 to be connected at a single point, making it easier to route the wiring.

[0029] 1 and 2 show an example in which a stator is constructed using one first sub-circuit board 2a and one second sub-circuit board 2b. However, as shown in FIG. 1, by arranging multiple sets of flexible circuit boards 1, each of which is a pair of a first sub-circuit board 2a and a second sub-circuit board 2b arranged in the X direction, it is possible to easily construct a long flexible circuit board that can be used to construct a stator compatible with a large motor.

[0030] [2. Stator manufacturing method] 3 to 5, a method for manufacturing the above-mentioned stator 70 will be described. As shown in Fig. 3, the manufacturing process for the stator 70 includes a "bonding step" in which adhesive 80 is applied to the inner peripheral surface of the prepared stator core 51 and a flexible circuit board 1 is bonded thereto, and a "pressure curing step" in which the adhesive is hardened while being pressed against the flexible circuit board 1 by a pressure jig 100.

[0031] The adhesive 80 is a room-temperature curing adhesive that does not require a heat source for curing, such as a two-component room-temperature curing epoxy adhesive, with a main component of epoxy, a curing agent of modified amine, a viscosity of 10 to 100 Pa·S, a tensile shear bond strength of 10 MPa or more, and heat resistance of 150°C-3000 hours or more. The pressure jig 100 is formed from a flexible ferromagnetic material such as a Nd rubber magnet.

[0032] 4 shows the state in which the pressing jig 100 is set in the "pressure hardening step." Because the pressing jig 100 is a permanent magnet, the pressing jig 100 is set by being magnetically attached to the inner circumferential side 51b of the stator core 51, which is made of a magnetic material, via the flexible circuit board 1. At this time, a magnetic force generated between the pressing jig 100 and the inner circumferential side 51b of the stator core 51 generates a pressing force, indicated by F in the figure, directed from the inside to the outside of the stator core 51.

[0033] This pressing force applies a constant pressure to the adhesive applied between the flexible circuit board 1 and the inner peripheral surface of the stator core 51. A plurality of pressing jigs 100 (12 in FIG. 4) are arranged along the inner peripheral surface of the stator core 51, and as shown in FIG. 5, each pressing jig 100 has a plate-like shape. Therefore, each pressing jig 100 maintains a uniform surface pressure that presses the flexible circuit board 1 against the inner peripheral surface of the stator core 51, hardening the adhesive.

[0034] Therefore, the flexible circuit board 1 can be accurately positioned and fixed at a predetermined position on the inner circumferential surface of the stator core 51, and the thickness of the adhesive 80 that fixes the flexible circuit board 1 can be controlled to be uniform (for example, within a range of 15±5 μm). This makes it possible to suppress non-uniformity in the magnetic flux distribution when the motor 50 is constructed, thereby improving the reliability of the motor 50.

[0035] Here, g in FIG. 1 indicates the clearance (air gap) between the inner periphery of the stator 70 and the outer periphery of the rotor 60, and the smaller the air gap g, the better the performance of the motor 50. In order to reduce the air gap, it is necessary not only to improve the precision of the components of the motor 50 as much as possible, but also to improve the assembly precision in the manufacturing process of the motor 50. Therefore, by using the "pressure curing process" described above, the adhesive is cured while the pressure jig 100 is magnetically attached to the inner periphery side 51b of the stator core 51, and the thickness of the adhesive 80 is controlled to be uniform throughout the entire flexible circuit board 1, thereby reducing the air gap g and improving the performance of the motor 50.

[0036] 4, it is preferable to set the allowable value of the distance d between adjacent pressing jigs 100 to less than 1 / 3 of the air gap g. For example, if the outer diameter φ of the stator 70 is 100 mm and the design value of the air gap g is 0.5 mm, the allowable value of the distance d is less than 0.5 / 3 = 0.1667. If the outer diameter φ of the stator 70 is 300 mm and the design value of the air gap g is 0.8 mm, the allowable value of the distance d is less than 0.8 / 3 = 0.2667.

[0037] [3. Formation of reinforcing wiring] Reinforcing wiring may be formed on the first sub-circuit board 2a and the second sub-circuit board 2b of the flexible circuit board 1 shown in Figure 2 to increase the strength of the board. By providing reinforcing wiring, the thickness of the flexible circuit board 1 can be reduced by eliminating the need to attach a reinforcing sheet or encapsulate with resin. Furthermore, by using a stator formed from a flexible circuit board 1 with such a reduced thickness, it is possible to reduce the size and weight of a rotating electric machine such as a motor. Below, a configuration in which reinforcing wiring is formed on the first sub-circuit board 2a will be described, but the same applies to the second sub-circuit board 2b.

[0038] (First Example of Reinforcing Wiring) Fig. 6 shows a first example of a configuration for forming reinforcing wiring. In the first example, first reinforcing wiring Sa is formed on the first surface 11a (front surface) of the first sub-circuit board 2a shown in Fig. 1, and second reinforcing wiring Sb is formed on the second surface 12a (back surface).

[0039] On the first surface 11a (front surface) of the insulating sheet 10a, on each of the long sides 13a and 14a, in the spaces H between the ends of the coil wirings 31a, 32, and 33a and the Y-direction end of the insulating sheet 10a, L-shaped first reinforcing wirings Sa are formed, which are electrically connected to adjacent ends of the coil wirings 31a, 32, and 33a and extend in the X-direction on the other end side. For example, at both ends of the coil wiring 31a in the Y direction, first reinforcing wirings Sa are formed, which extend in the X-direction on the side of the adjacent coil wiring 32a.

[0040] Similarly, on the second surface 12a (back surface) of the insulating sheet 10a, on each of the long sides 13a and 14a, in the spaces H between the ends of the coil wirings 31a, 32, and 33a and the Y-direction end of the insulating sheet 10a, L-shaped second reinforcing wirings Sb are formed, which are electrically connected to adjacent ends of the coil wirings 31a, 32, and 33a and extend in the X-direction on the other end side. For example, second reinforcing wirings Sb are formed at both ends of the coil wiring 32a in the Y direction, extending in the X-direction on the side of the adjacent coil wiring 33a.

[0041] 6 is a cross-sectional view of the first sub-circuit board 2a taken along the arrows A1-A1, with the insulating sheet 10a made transparent when viewed from the long side 13a. Also, K1 is a cross-sectional view of the first sub-circuit board 2a taken along the arrows B1-B1, with the insulating sheet 10a made transparent when viewed from the long side 14a. As shown in K1 and J1, the first reinforcing wiring Sa formed on the first surface 11a and the second reinforcing wiring Sb formed on the second surface 12a partially overlap in the X direction.

[0042] This results in wiring being formed over the entire range in the X direction in which the coil pattern is formed on both long sides 13 a and 14 b of first sub-circuit board 2 a, thereby increasing the strength of first sub-circuit board 2 a. Note that first reinforcing wiring Sa and second reinforcing wiring Sb may be formed only on either long side 13 a or long side 14 a.

[0043] (Second Example of Reinforcing Wiring) Figure 7 shows a second example of the configuration for forming reinforcing wiring. In the second example, a first first reinforcing wiring Sa1 and a second first reinforcing wiring Sa2 are formed on the first surface 11a (front surface) of the first sub-circuit board 2a shown in Figure 1.

[0044] On the first surface 11a (front surface) of the insulating sheet 10a, on each of the long sides 13a and 14a, in a space H between the ends of the coil wirings 31a, 32a, and 33a and the Y-direction end of the insulating sheet 10a, a T-shaped or L-shaped first first reinforcing wiring Sa1 and second first reinforcing wiring Sa2 are formed, which are electrically connected to adjacent ends of the coil wirings 31a, 32a, and 33a and extend in the X-direction on the other end side. The first first reinforcing wiring Sa1 and second first reinforcing wiring Sa2 are arranged with a gap in the Y direction.

[0045] For example, with respect to the coil wiring 31a, a first first reinforcing wiring Sa1 and a second first reinforcing wiring Sa2 are formed at both ends of the long side 13a and the long side 14a, and are electrically connected to the coil wiring 31a and extend in the X direction toward the adjacent coil wirings 32a and 33a.

[0046] 7 is a cross-sectional view of the first sub-circuit board 2a taken along the arrows A2-A2, viewed from the long side 13a, with the insulating sheet 10a made transparent. Also, K2 is a cross-sectional view of the first sub-circuit board 2a taken along the arrows B2-B2, viewed from the long side 14a, with the insulating sheet 10a made transparent. As shown in J2 and K2, the first first reinforcing wiring Sa1 and the second first reinforcing wiring Sa2 formed on the first surface 11a are arranged so that their positions in the X direction partially overlap.

[0047] This results in wiring being formed over the entire range in the X direction in which the coil pattern is formed on both long sides 13a and 14b of first sub-circuit board 2a, thereby increasing the strength of first sub-circuit board 2a. Note that first first reinforcing wiring Sa1 and second first reinforcing wiring Sa2 may be formed only on either long side 13a or long side 14a of first sub-circuit board 2a.

[0048] (Third Example of Reinforcing Wiring) Fig. 8 shows a third example of the configuration for forming reinforcing wiring. In the third example, for the first sub-circuit board 2a shown in Fig. 1, a first first reinforcing wiring Sa1 and a second first reinforcing wiring are formed on the first surface 11a (front surface), and a first second reinforcing wiring Sb1 and a second second reinforcing wiring Sb2 are formed on the second surface 12a (back surface).

[0049] On the first surface 11a (front surface) of the insulating sheet 10a, first first reinforcing wirings Sa1 and second first reinforcing wirings Sa2 are formed in the same arrangement pattern as in the second example shown in Fig. 8. Also on the second surface 12a (back surface) of the insulating sheet 10a, first second reinforcing wirings Sb1 and second second reinforcing wirings Sb2 are formed in the same arrangement pattern as in the second example shown in Fig. 8.

[0050] That is, on both the first surface 11a (front surface) and the second surface 12a (back surface) of the insulating sheet 10a, the first first reinforcing wiring Sa1 and the second first reinforcing wiring Sa2 are formed on the first surface 11a (front surface), and the first second reinforcing wiring Sb1 and the second second reinforcing wiring Sb2 are formed on the second surface 12a (back surface) in an arrangement pattern similar to that of the first first reinforcing wiring Sa1 and the second first reinforcing wiring Sa2 shown in the second example above.

[0051] 8 is a cross-sectional view of the first sub-circuit board 2a taken along the arrows A3-A3, as viewed from the long side 13a, with the insulating sheet 10a made transparent. Also, K3 is a cross-sectional view of the first sub-circuit board 2a taken along the arrows B3-B3, as viewed from the long side 14a, with the insulating sheet 10a made transparent. As shown in J3 and K3, the first first reinforcing wiring Sa1 and the second first reinforcing wiring Sa2 are formed on the first surface 11a so as to partially overlap in the X direction, and the first second reinforcing wiring Sb1 and the second second reinforcing wiring Sb2 are formed on the second surface 12a so as to partially overlap in the X direction.

[0052] This results in wiring being formed on both the long sides 13a and 14a of the first sub-circuit board 2a, on both the first surface 11a (front surface) and the second surface 12a (back surface), over the entire range in the X direction in which the coil pattern of the first sub-circuit board 2a is formed, thereby increasing the strength of the first sub-circuit board 2a. Note that the first first reinforcing wiring Sa1, the second first reinforcing wiring Sa2, the first second reinforcing wiring Sb1, and the second second reinforcing wiring may be formed only on one of the long sides 13a and 14a.

[0053] [4. Formation of protrusions] As shown in Fig. 9, the first sub-circuit board 2a and the second sub-circuit board 2b of the flexible circuit board 1 shown in Fig. 2 may be provided with positioning protrusions 40 for arranging the first sub-circuit board 2a and the second sub-circuit board 2b at predetermined positions on the stator core 51 (see Fig. 1), as shown in Fig. 9. Although Fig. 9 shows an example in which protrusions are provided on both the long side 13a and the long side 14 of the first sub-circuit board 2a, protrusions 40 may be provided on only one of the long side 13a and the long side 14a.

[0054] By forming the heat conduction pattern 41 on the protrusion 40 using a material with higher thermal conductivity than the material of the insulating sheet 10a, the heat generated in the flexible circuit board 1 can be efficiently dissipated to the outside of the case 51 via the heat conduction pattern 41 of the protrusion 40. The heat conduction pattern 41 is made of the same metal (copper, etc.) as the wiring such as the coil wirings 31a, 32a, 33a, etc.

[0055] 5. Other Embodiments In the above embodiment, the manufacturing method of the starter may include an "adhesive removal process" in which the adhesive 80 that has overflowed onto the end 52 of the stator core 51 (see Figure 5) during the "pressure hardening process" is removed before the hardening of the adhesive 80 is completed.

[0056] In the above embodiment, a "pressure hardening process" using multiple pressure jigs 100 is shown, but the pressure jig of the present disclosure may be a single belt-shaped pressure jig that is flexible and has a length similar to that of the flexible circuit board 1, or a single cylindrical pressure jig that is flexible and has a diameter similar to the inner diameter of the stator core 51.

[0057] In the above embodiment, the flexible circuit board 1 is configured by the first sub-circuit board 2a and the second sub-circuit board 2b, but it may be a single-sheet flexible circuit board.

[0058] 6. Configurations Supported by the Above Embodiments The above embodiment is a specific example of the following configuration.

[0059] (Configuration 1) A method for manufacturing a stator for a rotating electric machine by attaching a strip-shaped flexible circuit board, on which coil wiring has been formed, in a cylindrically bent state to the inner peripheral surface of a cylindrical stator core made of a magnetic material, the method including: an attachment process for applying a room temperature curing adhesive to at least one of the inner peripheral surface of the stator core and the outer peripheral surface of the flexible circuit board to attach the flexible circuit board to the inner peripheral surface of the stator core; and a pressure curing process for magnetically attaching a plate-shaped pressure jig formed of a permanent magnet to the inner peripheral surface of the stator core to which the flexible circuit board has been attached in the attachment process, along the circumferential direction of the stator core, thereby hardening the adhesive between the stator core and the flexible circuit board by maintaining a state in which a pressure is applied from the inside to the outside of the stator core by the magnetic force generated between the stator core and the pressure jig. According to the stator manufacturing method of configuration 1, it is possible to improve the uniformity of the adhesive when attaching the flexible circuit board on which the coil wiring is formed to the stator core.

[0060] (Configuration 2) The method for manufacturing a stator according to Configuration 1, wherein the pressure jig is composed of a plurality of sub-pressure jigs, and in the pressure hardening process, the plurality of sub-pressure jigs are arranged circumferentially around the stator core and magnetically attached to the inner surface of the stator core. According to the stator manufacturing method of configuration 2, by using a plurality of sub-pressing jigs, it is possible to easily arrange the pressing jigs on the inner peripheral surface of the stator core.

[0061] (Configuration 3) The method for manufacturing a stator according to Configuration 2, wherein the interval between adjacently arranged sub-pressure jigs is less than 1 / 3 of the interval between the flexible circuit board fixed to the inner surface of the stator core by the adhesive after the pressure curing process is completed, and a rotor arranged on the inner side of the flexible circuit board. According to the stator manufacturing method of configuration 3, the spacing between the multiple sub-pressure jigs can be appropriately set, thereby maintaining the uniformity of the adhesive that fixes the flexible circuit board to the stator core.

[0062] (Configuration 4) The method of manufacturing a stator according to any one of Configurations 1 to 3, wherein the pressing jig is made of a flexible ferromagnetic material. According to the stator manufacturing method of configuration 4, by making the pressing jig flexible, it is possible to increase the degree of adhesion when the pressing jig magnetically adheres to the inner surface of the stator core via the flexible circuit board and adhesive.

[0063] (Configuration 5) A method for manufacturing a stator according to any one of Configurations 1 to 4, wherein the magnetic attraction range of the pressing jig to the stator core in the pressure curing process and the magnetic force of the pressing jig are set under control conditions such that the thickness distribution of the adhesive between the stator core and the flexible circuit board becomes 15±5 μm as the adhesive hardens in the pressure curing process. According to the stator manufacturing method of configuration 5, a pressure curing process using a pressure jig allows the thickness distribution of the adhesive between the stator core and the flexible circuit board to be maintained at 15±5 μm while manufacturing the stator.

[0064] (Configuration 6) A method for manufacturing a stator according to any one of configurations 1 to 5, including an adhesive removal step of removing the adhesive that has protruded from the end of the stator core during the pressure hardening step before the adhesive has completely hardened. According to the stator manufacturing method of configuration 6, the adhesive that has protruded from the end of the stator core can be easily removed by wiping or the like before the room-temperature curing adhesive has completely hardened.

[0065] (Configuration 7) A rotating electric machine equipped with a stator configured by bending a strip-shaped flexible circuit board having coil wiring formed thereon into a cylindrical shape and attaching it to the inner surface of the cylindrical stator core formed from a magnetic material with a room temperature curing adhesive, wherein the thickness distribution of the adhesive between the stator core and the flexible circuit board is 15±5 μm. According to the rotating electric machine of configuration 7, by providing a stator in which the thickness distribution of the adhesive between the stator core and the flexible circuit board is maintained at 15±5 μm, a rotating electric machine with improved efficiency can be constructed.

[0066] (Configuration 8) A rotating electric machine according to Configuration 7, wherein the flexible circuit board comprises a flexible, strip-shaped insulating sheet and a predetermined number of the coil wirings for multiple phases formed extending in the longitudinal direction of the insulating sheet and arranged in parallel at intervals, and the flexible circuit board has a reinforcing wiring formed in the space of the insulating sheet between the short-side end of the insulating sheet of the coil wiring on at least one of the first and second surfaces of the insulating sheet and the short-side end of the insulating sheet, which is conductive to one of the short-side ends of the insulating sheet of the adjacent coil wiring and extends in the longitudinal direction of the insulating sheet on the other end side. According to the rotating electric machine of configuration 8, the strength of the flexible circuit board can be increased by forming reinforcing wiring on the flexible circuit board. This eliminates the need to attach a reinforcing sheet to the flexible circuit board or seal it with resin, and allows the thickness of the flexible circuit board to be reduced, making it possible to configure a rotating electric machine that can be made smaller and lighter.

[0067] (Configuration 9) A rotating electric machine according to Configuration 7 or 8, wherein the flexible circuit board comprises a flexible, strip-shaped insulating sheet, and a predetermined number of the coil wirings for multiple phases that are formed extending in the longitudinal direction of the insulating sheet and arranged in parallel at intervals, and has a positioning protrusion formed on the short-side end of the insulating sheet. According to the rotating electric machine of configuration 9, by forming a positioning protrusion on the flexible circuit board, it is possible to easily assemble the flexible circuit board, thereby making it possible to configure a rotating electric machine that is easy to manufacture. [Explanation of symbols]

[0068] 1...flexible circuit board, 2a...first sub-circuit board, 2b...first sub-circuit board, 10a, 10b...insulating sheet, 20a, 20b...connection portion, 21a to 23a, 21b to 23b...connection terminal, 31a to 33a, 31b to 33b...coil wiring, 40...positioning protrusion, 41...heat conduction pattern, 50...motor, 51...stator core, 60...rotor, 70...stator, 71a, 71b...external terminal, 80...adhesive, 90...external circuit, Sa...first reinforcing wiring, Sa1...first first reinforcing wiring, Sa2...second first reinforcing wiring, Sb...second reinforcing wiring, Sb1...first second reinforcing wiring, Sb2...second second reinforcing wiring.

Claims

1. A method for manufacturing a stator for a rotating electric machine by attaching a strip-shaped flexible circuit board having coil wiring formed thereon in a cylindrically bent state to an inner peripheral surface of a cylindrical stator core made of a magnetic material, the method comprising: a bonding process of applying a room temperature curing adhesive to at least one of an inner peripheral surface of the stator core and an outer peripheral surface of the flexible circuit board, and bonding the flexible circuit board to the inner peripheral surface of the stator core; and a pressure curing process in which a plate-shaped pressure jig formed by a permanent magnet is magnetically attached to the inner peripheral surface of the stator core to which the flexible circuit board has been attached in the pasting process, along the circumferential direction of the stator core, thereby hardening the adhesive by maintaining a state in which a pressure from the inside to the outside of the stator core is applied to the adhesive between the stator core and the flexible circuit board by a magnetic force generated between the stator core and the pressure jig. A method for manufacturing a stator.

2. The pressure jig is composed of a plurality of sub-pressure jigs, In the pressure hardening step, the plurality of sub-pressure jigs are arranged in the circumferential direction of the stator core and magnetically attached to the inner peripheral surface of the stator core. The method for manufacturing the stator according to claim 1 .

3. The interval between the adjacently arranged sub-pressure jigs is less than one-third of the interval between the flexible circuit board fixed to the inner peripheral surface of the stator core by the adhesive after the pressure curing step is completed and the rotor arranged on the inner peripheral side of the flexible circuit board. The method for manufacturing a stator according to claim 2 .

4. The pressure jig is made of a flexible ferromagnetic material. A method for manufacturing a stator according to any one of claims 1 to 3.

5. The magnetic attraction range of the pressure jig to the stator core in the pressure hardening process and the magnetic force of the pressure jig are set under control conditions such that the thickness distribution of the adhesive between the stator core and the flexible circuit board becomes 15±5 μm as the adhesive hardens in the pressure hardening process. A method for manufacturing a stator according to any one of claims 1 to 3.

6. an adhesive removing step of removing the adhesive that has protruded from the end of the stator core in the pressure hardening step before hardening of the adhesive is completed; The method for manufacturing a stator according to claim 1 or 2.

7. The stator is configured by bending a strip-shaped flexible circuit board, on which coil wiring is formed, into a cylindrical shape and attaching it to the inner peripheral surface of the cylindrical stator core made of a magnetic material with a room temperature curing adhesive, and the thickness distribution of the adhesive between the stator core and the flexible circuit board is 15±5 μm. Rotating electric motor.

8. The flexible circuit board is The coil winding includes a flexible, strip-shaped insulating sheet and a predetermined number of coil wirings for a plurality of phases, the coil wirings being formed to extend in the longitudinal direction of the insulating sheet and arranged in parallel at intervals, A reinforcing wire is provided in a space of the insulating sheet between an end of the coil wiring in the short direction of the insulating sheet on at least one of the first surface and the second surface of the insulating sheet and an end of the insulating sheet in the short direction, the reinforcing wire being electrically connected to one end of the short direction of the insulating sheet of the adjacent coil wiring and extending in the longitudinal direction of the insulating sheet on the other end side. The rotating electric machine according to claim 7.

9. The flexible circuit board is The coil winding includes a flexible, strip-shaped insulating sheet and a predetermined number of coil wirings for a plurality of phases, the coil wirings being formed to extend in the longitudinal direction of the insulating sheet and arranged in parallel at intervals, The insulating sheet has a positioning projection formed on the end portion in the lateral direction. The rotating electric machine according to claim 7.

Images