Stator, motor, fan device, and coil winding method

Abstract

To provide a stator whose stator core can be miniaturized in an axial direction and which can stably drive a motor.SOLUTION: A stator comprises: an A-phase coil wound around four teeth among twelve teeth and to which current in an A phase is supplied; a B-phase coil wound around four other teeth among the twelve teeth and to which current in a B phase is supplied; and a C-phase coil wound around the four remaining teeth among the twelve teeth and to which current in a C phase is supplied. The A-phase coil includes a crossover part extended along a cylindrical part on one side in an axial direction between teeth separated in a circumferential direction. Each of the B-phase coil and the C-phase coil includes a crossover part extended along a cylindrical part on the other side in the axial direction between the teeth separated in the circumferential direction. The total number of windings of the A-phase coil is fewer than the total number of windings of the B-phase coil and the total number of windings of the C-phase coil, by two windings.SELECTED DRAWING: Figure 6

Description

Technical Field

[0005]

[0001] The present invention relates to a stator, a motor, a fan device equipped with the same, and a method for winding a coil around the stator.

Background Art

[0002] In recent years, efforts have been made to promote the Sustainable Development Goals (the 2030 Agenda for Sustainable Development, adopted at the United Nations Summit on September 25, 2015, hereinafter referred to as "SDGs"). Along with this, technologies aiming to reduce waste and defective products are known in order to ensure sustainable production and consumption patterns. [[ID=~]] [[ID=~]]

[0003] [[ID=~]] In a three-phase AC motor, a U-phase coil is wound around a part of a plurality of teeth, a V-phase coil is wound around another part of the plurality of teeth, and a W-phase coil is wound around still another part of the plurality of teeth. And each of the three coils is provided with a bridging portion that crosses between teeth spaced apart in the circumferential direction.

[0004] When the bridging portions of the three coils are concentrated on one side in the axial direction of the stator core, the axial length of the stator core becomes long. Therefore, Patent Document 1 discloses a motor in which a bridging portion of a part of the three coils is arranged on one side in the axial direction of the stator core, and a bridging portion of another part is arranged on the other side in the axial direction of the stator core.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] [[ID=4~]] However, the number of turns per tooth differs between a coil with the connecting section on one side of the stator core in the axial direction and a coil with the connecting section on the other side of the stator core in the axial direction. As a result, there is a problem of unstable motor operation.

[0007] Therefore, the object of the present invention is to provide a stator that can stably drive a motor while miniaturizing the stator core in the axial direction. [Means for solving the problem]

[0008] To achieve the above objective, the present invention provides a stator comprising 12 teeth arranged in a ring shape and spaced apart in the circumferential direction, cylindrical portions protruding axially from the inner or outer circumference of the 12 teeth on both sides, and coils wound around each of the 12 teeth, wherein the coils are A-phase coils wound around four of the 12 teeth to supply A-phase current, B-phase coils wound around the other four of the 12 teeth to supply B-phase current, and 12 The A-phase coil includes a C-phase coil wound around four other teeth of the A-phase coil to which C-phase current is supplied, wherein the A-phase coil includes a connecting portion extending along one side of the cylindrical portion in the axial direction between the circumferentially spaced teeth, and the B-phase coil and the C-phase coil each include a connecting portion extending along the other side of the cylindrical portion in the axial direction between the circumferentially spaced teeth, and the total number of turns of the A-phase coil is two turns less than the total number of turns of the B-phase coil and the total number of turns of the C-phase coil. The A-phase coil is wound around each of the four teeth, and between the teeth adjacent to the tooth in the circumferential direction, there is a diagonal wire that connects the A-phase coil and the connecting portion, and each of these wires functions as a coil of 0.5 turns. It is characterized by the following: [Effects of the Invention]

[0009] According to the present invention, it is possible to obtain a stator that can be miniaturized in the axial direction and that can stably drive a motor. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments. [Brief explanation of the drawing]

[0010] [Figure 1] This is an external perspective view showing one example configuration of a fan device according to the embodiment. [Figure 2] This is a disassembled perspective view of the motor and fan after they have been taken apart. [Figure 3] This is a perspective view of the motor from the front. [Figure 4] This is a perspective view showing the motor configuration with the rotor yoke removed. [Figure 5] Figure 3 is a cross-sectional view along the VV line. [Figure 6] This is a diagram showing the teeth and coil unfolded. [Figure 7] This is a schematic diagram of a delta connection in a coil. [Figure 8] This is a perspective view of the stator from the front side. [Figure 9] This is a perspective view of the stator from the back side. [Figure 10] This diagram shows the procedure for winding a coil. [Modes for carrying out the invention]

[0011] Hereinafter, as one embodiment of the fan device according to the present invention, a fan device mounted on a vehicle such as an automobile and used to cool engine coolant flowing in a radiator will be described.

[0012] (Overall configuration of fan device 1) First, the overall configuration of the fan device 1 will be described with reference to Figures 1 and 2. Figure 1 is an external perspective view showing one example configuration of the fan device 1 according to the embodiment. Figure 2 is an exploded perspective view when the motor 2 and fan 3 are separated. As shown in Figures 1 and 2, the fan device 1 comprises a motor 2, which is a drive source, and a fan 3, which is rotated by the motor 2 to generate cooling air.

[0013] (Motor 2 configuration) Next, referring to FIGS. 3 to 5, the configuration of the motor 2 will be described. FIG. 3 is an external perspective view of the motor 2 as viewed from the front side. FIG. 4 is a perspective view showing the configuration of the motor 2 with the rotor yoke 232 removed. FIG. 5 is a cross-sectional view taken along the line V-V in FIG. 3.

[0014] As shown in FIGS. 3 to 5, the motor 2 is a so-called "mechatronic" electric motor including an outer-rotor type brushless motor 201 and a driver circuit 202 that controls the brushless motor 201 (more specifically, the generation of a magnetic field by the coil 243). Note that for the motor 2 according to the present embodiment, if it has 12 slots, the number of poles is not particularly limited.

[0015] The brushless motor 201 is supported by a plate-shaped motor bracket 203. The brushless motor 201 is disposed on one side (front side) in the thickness direction of the motor bracket 203.

[0016] As shown in FIG. 5, on the other side (back side) in the thickness direction of the motor bracket 203, a driver bracket 204 is fastened by a plurality of screws 205. Thereby, a housing space 206 is formed between the motor bracket 203 and the driver bracket 204. And the driver circuit 202 is housed in this housing space 206.

[0017] Also, at the end of the motor bracket 203, a connector unit 207 in which two connectors to which an external harness is connected are integrated is attached. The brushless motor 201, the driver circuit 202, and the connector unit 207 are electrically connected to each other via the motor bracket 203.

[0018] As shown in FIGS. 4 and 5, the brushless motor 201 has a shaft 21, bearings 22A and 22B provided on the outer periphery of the shaft 21, a rotor 23 rotatably supported around the axis of the shaft 21 via the bearings 22A and 22B, and an annular stator 24 around which a coil 243 for generating a magnetic field for rotating the rotor 23 is wound.

[0019] The shaft 21 is a fixed shaft fixed to the surface side of the motor bracket 203. In the following description of the components of the motor 2, the axial direction of the shaft 21 will be simply referred to as the "axial direction," the radial direction centered on the axis of the shaft 21 will be simply referred to as the "radial direction," and the circumferential direction centered on the axis of the shaft 21 will be simply referred to as the "circumferential direction."

[0020] The rotor 23 has a plurality of permanent magnets 231 arranged at equal intervals in the circumferential direction so as to surround the outer circumference of the stator 24, and a rotor yoke 232 that covers the stator 24 and the plurality of permanent magnets 231. The rotor yoke 232 is positioned on the surface side of the motor bracket 203 so as to be concentric with the axis of the shaft 21. The rotor yoke 232 is also rotatably supported on the shaft 21 via bearings 22A and 22B. The rotor yoke 232 mainly comprises an outer circumferential wall 232A, an inner circumferential wall 232B, and a connecting wall 232C.

[0021] The outer periphery wall 232A has a cylindrical shape. Furthermore, the outer periphery wall 232A is positioned radially outward from the stator 24. In addition, the outer periphery wall 232A supports multiple permanent magnets 231 on its inner surface. In other words, the multiple permanent magnets 231 are fixed to the inner surface of the outer periphery wall 232A, spaced apart in the circumferential direction to surround the stator 24.

[0022] The inner circumferential wall 232B has a cylindrical outer shape. Furthermore, the inner circumferential wall 232B is positioned radially inward from the stator 24. In addition, the inner circumferential wall 232B is rotatably supported by the shaft 21 via bearings 22A and 22B.

[0023] The connecting wall 232C has a disc-shaped outer form. The connecting wall 232C also connects the axial ends of the outer circumferential wall 232A and the inner circumferential wall 232B. More specifically, as shown in Figure 5, the connecting wall 232C connects the outer circumferential wall 232A and the inner circumferential wall 232B at the other axial end of the shaft 21 (i.e., the side opposite to the motor bracket 203).

[0024] The stator 24 is housed in a space enclosed by the outer peripheral wall 232A, the inner peripheral wall 232B, the connecting wall 232C, and the motor bracket 203. As shown in Figure 3, the stator 24 is fixed to the surface side of the motor bracket 203 radially inward from the multiple permanent magnets 231. Furthermore, the stator 24 faces the multiple permanent magnets 231 with a predetermined gap in the radial direction. As shown in Figures 4 and 5, the stator 24 consists of a stator core 240 composed of a cylindrical cylindrical portion 241 and multiple (12 in this embodiment) teeth 242, and multiple coils 243.

[0025] The cylindrical portion 241 has a cylindrical shape with both ends open in the axial direction. The cylindrical portion 241 is fixed to the surface side of the motor bracket 203 at a position surrounding the shaft 21. The 12 teeth 242 protrude radially outward from positions spaced apart in the circumferential direction on the outer surface of the cylindrical portion 241. Furthermore, both ends of the cylindrical portion 241 in the axial direction protrude from the positions of the teeth 242 on both sides. In other words, the 12 teeth 242 are arranged in a ring shape, spaced apart in the circumferential direction. The cylindrical portion 241 also protrudes from the inner circumference of the 12 teeth on both sides in the axial direction.

[0026] The 12 teeth 242 are formed, for example, from multiple steel plates stacked in the axial direction. The stator core 240 is constructed by covering the stacked steel plates with an insulating insulator. Furthermore, the coil 243 is wound around the teeth 242 from above the insulator. The cylindrical portion 241 is part of the insulator.

[0027] Multiple coils 243 are wound around each of the multiple teeth 242. The multiple coils 243 are also connected to a driver circuit 202. The driver circuit 202 supplies either U-phase, V-phase, or W-phase current to the multiple coils 243. This causes the multiple coils to generate a magnetic field that rotates the rotor 23. More specifically, the attractive and repulsive forces between the magnetic field generated by the coils 243 and the multiple permanent magnets 231 cause the rotor yoke 232 to rotate around the axis of the shaft 21.

[0028] Figure 6 shows the teeth 242 and coil 243 in an unfolded state. Figure 7 is a schematic diagram of the delta connection of coil 243. Figure 8 is a perspective view of the stator 24 from the front side (opposite side of the motor bracket 203). Figure 9 is a perspective view of the stator 24 from the back side (motor bracket 203 side).

[0029] As shown in Figures 6 and 7, the multiple coils 243 include coils 243U1 (first A-phase coil) and 243U2 (second A-phase coil) to which U-phase (A-phase) current is supplied, coils 243V1 (first B-phase coil) and 243V2 (second B-phase coil) to which V-phase (B-phase) current is supplied, and coils 243W1 (first C-phase coil) and 243W2 (second C-phase coil) to which W-phase (C-phase) current is supplied.

[0030] Coils 243U1 and 243U2 are examples of A-phase coils, coils 243V1 and 243V2 are examples of B-phase coils, and coils 243W1 and 243W2 are examples of C-phase coils. In this embodiment, (A-phase, B-phase, C-phase) is associated with (U-phase, V-phase, W-phase), but this combination is not limited to the examples described above.

[0031] Furthermore, the coil 243 includes two connection ends 244 and 245 connected to the driver circuit 202, two coil sections 246 and 247 wound around the teeth 242, and a connecting section 248 that spans between the circumferentially spaced teeth 242. The connection ends 244 and 245 are the ends of the coil 243. The connecting section 248 is the section between the coil sections 246 and 247. In other words, coil section 246 is located between connection end 244 and connecting section 248, and coil section 247 is located between connection end 245 and connecting section 248.

[0032] Furthermore, in the following explanation, the 12 teeth 242 will be referred to as, in clockwise order in Figure 8, the 1st tooth W1, the 2nd tooth U2, the 3rd tooth U3, the 4th tooth V4, the 5th tooth V5, the 6th tooth W6, the 7th tooth W7, the 8th tooth U8, the 9th tooth U9, the 10th tooth V10, the 11th tooth V11, and the 12th tooth W12.

[0033] Coil 243U1 is wound from the driver circuit 202 to the third tooth U3 and the eighth tooth U8 and returns to the driver circuit 202. More specifically, the connecting end 244U1 connected to the driver circuit 202 passes between the second tooth U2 and the third tooth U3, coil portion 246U1 is wound around the third tooth U3, coil portion 247U1 is wound around the eighth tooth U8, and the connecting end 245U1, which passes between the eighth tooth U8 and the ninth tooth U9, is connected to the driver circuit 202. Also, as shown in Figure 9(B), the connecting portion 248U1 extends along the cylindrical portion 241 between the circumferentially spaced third tooth U3 and the eighth tooth U8, on the motor bracket 203 side (i.e., one side in the axial direction) from tooth 242.

[0034] The coil 243U2 is wound from the driver circuit 202 around the ninth tooth U9 and the second tooth U2 and returns to the driver circuit 202. More specifically, the connecting end 244U2 connected to the driver circuit 202 passes between the eighth tooth U8 and the ninth tooth U9, the coil portion 246U2 is wound around the ninth tooth U9, the coil portion 247U2 is wound around the second tooth U2, and the connecting end 245U2, which passes between the second tooth U2 and the third tooth U3, is connected to the driver circuit 202. Also, as shown in Figure 9(A), the connecting portion 248U2 extends along the cylindrical portion 241 between the circumferentially spaced ninth tooth U9 and the second tooth U2, on the motor bracket 203 side (i.e., one side in the axial direction) from tooth 242.

[0035] Specifically, coil 243U1 is wound in series around the circumferentially spaced third teeth U3 and eighth teeth U8. Coil 243U2 is wound in series around the circumferentially spaced ninth teeth U9 and second teeth U2. Coils 243U1 and 243U2 are connected in parallel. Furthermore, one coil section 246U1 and 247U1 has N turns (where N is an integer greater than or equal to 2), and the other has (N-1) turns. One coil section 246U2 and 247U2 has N turns, and the other has (N-1) turns. That is, the total number of turns for coils 243U1 and 243U2 is 2N-1 turns.

[0036] Coil 243V1 is wound from the driver circuit 202 to the fifth tooth V5 and the tenth tooth V10 and returns to the driver circuit 202. More specifically, the connecting end 244V1 connected to the driver circuit 202 passes between the fourth tooth V4 and the fifth tooth V5, coil section 246V1 is wound around the fifth tooth V5, coil section 247V1 is wound around the tenth tooth V10, and the connecting end 245V1, which passes between the tenth tooth V10 and the eleventh tooth V11, is connected to the driver circuit 202. Also, as shown in Figure 8(B), the connecting section 248V1 extends along the cylindrical section 241 between the circumferentially spaced fifth tooth V5 and the tenth tooth V10, on the side opposite to the motor bracket 203 from tooth 242 (i.e., the other side in the axial direction).

[0037] Coil 243V2 is wound from the driver circuit 202 around the 11th tooth V11 and the 4th tooth V4 and returns to the driver circuit 202. More specifically, the connecting end 244V2 connected to the driver circuit 202 passes between the 10th tooth V10 and the 11th tooth V11, coil section 246V2 is wound around the 11th tooth V11, coil section 247V2 is wound around the 4th tooth V4, and the connecting end 245V2, which passes between the 4th tooth V4 and the 5th tooth V5, is connected to the driver circuit 202. Also, as shown in Figure 8(A), the connecting section 248V2 extends along the cylindrical section 241 between the circumferentially spaced 11th tooth V11 and the 4th tooth V4, on the side opposite to the motor bracket 203 from tooth 242 (i.e., the other side in the axial direction).

[0038] Specifically, coil 243V1 is wound in series with the 5th tooth V5 and the 10th tooth V10, which are spaced apart in the circumferential direction. Coil 243V2 is wound in series with the 11th tooth V11 and the 4th tooth V4, which are spaced apart in the circumferential direction. Coils 243V1 and 243V2 are connected in parallel. Furthermore, the number of turns in each of the coil sections 246V1, 247V1, 246V2, and 247V2 is N turns. That is, the total number of turns in coils 243V1 and 243V2 is 2N turns.

[0039] Coil 243W1 is wound from the driver circuit 202 around the first tooth W1 and the sixth tooth W6 and returns to the driver circuit 202. More specifically, the connecting end 244W1 connected to the driver circuit 202 passes between the twelfth tooth W12 and the first tooth W1, coil section 246W1 is wound around the first tooth W1, coil section 247W1 is wound around the sixth tooth W6, and the connecting end 245W1, which passes between the sixth tooth W6 and the seventh tooth W7, is connected to the driver circuit 202. Also, as shown in Figure 8(A), the connecting section 248W1 extends along the cylindrical section 241 between the circumferentially spaced first tooth W1 and the sixth tooth W6, on the side opposite to the motor bracket 203 from tooth 242 (i.e., the other side in the axial direction).

[0040] Coil 243W2 is wound from the driver circuit 202 to the 7th tooth W7 and the 12th tooth W12 and returns to the driver circuit 202. More specifically, the connecting end 244W2 connected to the driver circuit 202 passes between the 6th tooth W6 and the 7th tooth W7, coil section 246W2 is wound around the 7th tooth W7, coil section 247W2 is wound around the 12th tooth W12, and the connecting end 245W2, which passes between the 12th tooth W12 and the 1st tooth W1, is connected to the driver circuit 202. Also, as shown in Figure 8(B), the connecting section 248W2 extends along the cylindrical section 241 between the circumferentially spaced 7th tooth W7 and the 12th tooth W12, on the side opposite to the motor bracket 203 from tooth 242 (i.e., the other side in the axial direction).

[0041] Specifically, coil 243W1 is wound in series around the circumferentially spaced first teeth W1 and sixth teeth W6. Coil 243W2 is wound in series around the circumferentially spaced seventh teeth W7 and twelfth teeth W12. Coils 243W1 and 243W2 are connected in parallel. Furthermore, the number of turns in each of the coil sections 246W1, 247W1, 246W2, and 247W2 is N turns. That is, the total number of turns in coils 243W1 and 243W2 is 2N turns.

[0042] From the above, the total number of turns of coil 243U1 (2N-1) is 1 turn less than the total number of turns of coil 243V1 (2N) and the total number of turns of coil 243W1 (2N). Also, the total number of turns of coil 243U2 (2N-1) is 1 turn less than the total number of turns of coil 243V2 (2N) and the total number of turns of coil 243W2 (2N). Furthermore, the total number of turns of the U-phase coils 243U1 and 243U2 (4N-2) is 2 turns less than the total number of turns of the V-phase coils 243V1 and 243V2 (4N) and the total number of turns of the W-phase coils 243W1 and 243W2 (4N).

[0043] Note that the parts of coils 243U1 and 243U2 that connect the coil sections 246U1, 247U1, 246U2, and 247U2 with the connecting sections 248U1, 248U2 (the four parts shown by diagonal lines between circumferentially adjacent teeth 242 in Figure 6) are not counted in the aforementioned number of turns. In other words, the aforementioned number of turns only counts the number of turns wound by, for example, a well-known winding machine. However, each of the four parts shown by diagonal lines in Figure 6 generates a magnetic field equivalent to 0.5 turns. Therefore, by maintaining the aforementioned relationship between the total number of turns of the U-phase coils 243U1 and 243U2, the total number of turns of the V-phase coils 243V1 and 243V2, and the total number of turns of the W-phase coils 243W1 and 243W2, the overall balance of the magnetic field is maintained.

[0044] On the other hand, if we count the turns in the four sections indicated by the diagonal lines in Figure 6, then one of the coil sections 246U1 and 247U1 will have (N+0.5) turns, and the other will have (N-0.5) turns. Similarly, one of the coil sections 246U2 and 247U2 will have (N+0.5) turns, and the other will have (N-0.5) turns. In other words, the total number of turns in the coil sections 246U1 and 247U1 is 2N turns, and the total number of turns in the coil sections 246U2 and 247U2 is also 2N turns. Furthermore, the total number of turns in the U-phase coils 243U1 and 243U2 is 4N turns.

[0045] Furthermore, as shown in Figure 6, the connection ends 244V1, 245V1, 244V2, 245V2, 244W1, 245W1, 244W2, and 245W2 of coils 243V1, 243V2, 243W2 extend to the driver circuit 202, passing radially outside the connecting portions 248U1 and 248U2 of coils 243U1 and 243U2.

[0046] Furthermore, as shown in Figure 9, the motor 2 includes a plurality of positioning sections 25A, 25B, 25C, 25D, 25E, and 25F. The positioning sections 25A to 25F are located on the motor bracket 203 side of the teeth 242. Also, the positioning sections 25A to 25F are arranged at predetermined intervals in the circumferential direction along the cylindrical section 241. Furthermore, the positioning sections 25A to 25F are fixed to the stator 24 (more specifically, the insulator) and housed in recesses of the motor bracket 203.

[0047] Positioning sections 25A to 25F position the connection ends 244U1, 245U1, 244U2, 245U2, 244V1, 245V1, 244V2, 245V2, 244W1, 245W1, 244W2, and 245W2. More specifically, the connecting ends 244W1 and 245W2 are inserted into and positioned in the positioning section 25A, the connecting ends 244U1 and 245U2 are inserted into and positioned in the positioning section 25B, the connecting ends 244V1 and 245V2 are inserted into and positioned in the positioning section 25C, the connecting ends 244W2 and 245W1 are inserted into and positioned in the positioning section 25D, the connecting ends 244U2 and 245U1 are inserted into and positioned in the positioning section 25E, and the connecting ends 244V2 and 245V1 are inserted into and positioned in the positioning section 25F.

[0048] Next, with reference to Figure 10, the winding direction of the coil 243 relative to the stator 24 will be explained. Figure 10 shows the procedure for winding the coil 243.

[0049] First, coils 243U1 and 243U2 are wound onto tooth 242 using a winding machine (S1). The total number of turns in step S1 is (4N-2) turns. More specifically, coil section 246U1 is wound onto the third tooth U3, a connecting section 248U1 is extended from tooth 242 along the cylindrical section 241 on the motor bracket 203 side, and coil section 247U1 is wound onto the eighth tooth U8. Also, coil section 246U2 is wound onto the ninth tooth U9, a connecting section 248U2 is extended from tooth 242 along the cylindrical section 241 on the motor bracket 203 side, and coil section 247U2 is wound onto the second tooth U2.

[0050] Next, after step S1 is performed, coils 243V1 and 243V2 are wound onto tooth 242 by a winding machine (S2). The total number of turns in step S2 is 4N turns. More specifically, coil section 246V1 is wound onto the fifth tooth V5, a connecting section 248V1 is extended from tooth 242 along the cylindrical section 241 on the opposite side of the motor bracket 203, and coil section 247V1 is wound onto the tenth tooth V10. Also, coil section 246V2 is wound onto the eleventh tooth V11, a connecting section 248V2 is extended from tooth 242 along the cylindrical section 241 on the opposite side of the motor bracket 203, and coil section 247V2 is wound onto the fourth tooth V4.

[0051] Furthermore, after step S1 is performed, coils 243W1 and 243W2 are wound onto teeth 242 by a winding machine (S3). The total number of turns in step S3 is 4N turns. More specifically, coil section 246W1 is wound onto the first tooth W1, a connecting section 248W1 is extended from tooth 242 along the cylindrical section 241 on the opposite side of the motor bracket 203, and coil section 247W1 is wound onto the sixth tooth W6. Also, coil section 246W2 is wound onto the seventh tooth W7, a connecting section 248W2 is extended from tooth 242 along the cylindrical section 241 on the opposite side of the motor bracket 203, and coil section 247W2 is wound onto the twelfth tooth W12.

[0052] By performing steps S2 and S3 after step S1, the connecting ends 244V1, 245V1, 244V2, 245V2, 244W1, 245W1, 244W2, and 245W2 of coils 243V1, 243V2, 243W1, 243W2 are positioned radially outward from the connecting portions 248U1 and 248U2 of coils 243U1 and 243U2. Note that the order in which steps S2 and S3 are performed is not limited to the example in Figure 10, and may be performed in reverse order.

[0053] Next, after performing steps S1 to S3, a so-called "forming process" is performed (S4) in which the connecting ends 244U1, 245U1, 244U2, 245U2, 244V1, 245V1, 244V2, 245V2, 244W1, 245W1, 244W2, and 245W2 are inserted into the positioning sections 25A to 25F and positioned. More specifically, the connecting ends 244U1, 245U1, 244U2, 245U2, 244V1, 245V1, 244V2, 245V2, 244W1, 245W1, 244W2, and 245W2 are pulled and inserted into the positioning sections 25A to 25F while a predetermined tension is applied.

[0054] Next, after performing step S4, the connection terminals 244U1, 245U1, 244U2, 245U2, 244V1, 245V1, 244V2, 245V2, 244W1, 245W1, 244W2, and 245W2 are connected to the driver circuit 202 (S5).

[0055] (Fan 3 configuration) As shown in Figures 1 and 2, the fan 3 has a boss portion 31 that rotates integrally with the rotor 23 with the axis of rotation on the shaft 21, a plurality of blades 32 (seven in this embodiment) that protrude radially from the outer circumference of the boss portion 31, and a plurality of connecting members 33 (seven in this embodiment) that connect adjacent blades 32 at their tips.

[0056] Furthermore, the boss portion 31 includes a disc-shaped disc portion 311 and a cylindrical peripheral wall portion 312 that protrudes from the outer edge of the disc portion 311 toward the motor 2 and to which a plurality of blades 32 are attached. When the fan 3 is attached to the motor 2, the disc portion 311 faces the connecting wall 232C of the rotor yoke 232, and the peripheral wall portion 312 surrounds the outer peripheral wall 232A of the rotor yoke 232.

[0057] As shown in Figure 2, the fan 3 is fastened to the rotor yoke 232 by screws 10. In this embodiment, considering the rotational balance of the fan 3, the three screws 10 are mounted at equal intervals on the circumference of the fan 3 centered on its rotation center. It is not necessary to use three screws 10 as fastening members to fasten the fan 3 to the motor 2; there are no particular restrictions on the number of screws 10 or the type of fastening members as long as the fan 3 can be fastened to the motor 2.

[0058] According to the above embodiment, for example, the following effects are achieved.

[0059] According to the above embodiment, the U-phase connecting sections 248U1 and 248U2 and the V-phase and W-phase connecting sections 248V1, 248V2, 248W1 and 248W2 are distributed on opposite sides in the axial direction with respect to the teeth 242. Compared to concentrating all the connecting sections on one side in the axial direction, the stator core 240 can be made smaller in the axial direction. This contributes to the miniaturization of the fan device 1 and the motor 2.

[0060] Furthermore, by making the total number of turns of the U-phase coils 243U1 and 243U2 (4N-2) two turns less than the total number of turns of the V-phase coils 243V1 and 243V2 (4N) and the total number of turns of the W-phase coils 243W1 and 243W2 (4N), the difference in the number of turns resulting from distributing the connecting sections 248U1 and 248U2 with the connecting sections 248V1, 248V2, 248W1, and 248W2 can be absorbed. This allows the motor 2 to be driven stably. As a result, the lifespan of the motor 2 and the fan device 1 equipped with it can be extended, contributing to the reduction of waste and defective products.

[0061] Here, if the total number of turns of one of the coils 243U1 or 243U2 is reduced by 2 turns, the voltage across coils 243U1 and 243U2 becomes uneven, causing a circulating current. Therefore, as in the embodiment described above, by reducing the total number of turns of the coils 243U1 and 243U2 connected in parallel by 1 turn each, the motor 2 can be driven even more stably.

[0062] Furthermore, according to the above embodiment, the forming process is facilitated by passing the connecting ends 244V1, 245V1, 244V2, 245V2, 244W1, 245W1, 244W2, and 245W2 radially outside the connecting portions 248U1 and 248U2 of the coils 243U1 and 243U2. This can be achieved by winding the coil 243 in the procedure shown in Figure 10.

[0063] In the above embodiment, an example of applying the present invention to an outer rotor type motor 2 in which the rotor 23 is arranged outside the stator 24 was described. However, the present invention is also applicable to an inner rotor type motor in which the rotor is arranged inside the stator. In an inner rotor type motor, the cylindrical portion protrudes from both sides in the axial direction from the outer circumference of the 12 stators.

[0064] Furthermore, in the above embodiment, an example of the use of the fan device 1 was described as supplying cooling air to a radiator, but the use of the fan device 1 is not limited to this. Also, in the above embodiment, an example of the use of the motor 2 was described as a fan motor that rotates and drives the fan 3, but the use of the motor 2 is not limited to this.

[0065] Embodiments of the present invention have been described above. It should be noted that the present invention is not limited to the embodiments described above, and various modifications are included. For example, the embodiments described above are described in detail to make the present invention easier to understand, and are not necessarily limited to those having all the described configurations. Furthermore, it is possible to replace some of the configurations of this embodiment with those of other embodiments, and it is also possible to add configurations from other embodiments to the configuration of this embodiment. Moreover, it is possible to add, delete, or replace some of the configurations of this embodiment with those of other embodiments. [Explanation of symbols]

[0066] 1: Fan device 2: Motor 3: Fan 10,205: Screws 21: Shaft 22A, 22B: Bearings 23: Rotor 24: Status 25A~25F: Positioning section 31: Boss Department 32: Feather 33: Connecting member 201: Brushless motor 202: Driver Circuit 203: Motor bracket 204: Driver bracket 206: Containment Space 207: Connector Unit 231: Permanent magnet 232: Rotor yoke 232A: Outer wall 232B: Inner wall 232C: Connecting wall 240: Stator core 241: Cylindrical section 242: Teeth 243: Coil 244,245: Connection ends 246,247: Coil section 248: Watari-bu 311: Disc section 312: Peripheral wall part

Claims

1. A stator comprising 12 teeth arranged in a ring shape and spaced apart in the circumferential direction, cylindrical portions protruding axially from the inner or outer circumference of the 12 teeth on both sides, and coils wound around each of the 12 teeth, The aforementioned coil is An A-phase coil is wound around four of the twelve teeth and supplied with A-phase current, A B-phase coil is wound around the other four of the twelve teeth and supplied with B-phase current, It includes a C-phase coil wound around four of the twelve teeth, to which the C-phase current is supplied, The A-phase coil includes a connecting portion that extends along the cylindrical portion on one side in the axial direction between the teeth which are spaced apart in the circumferential direction. Each of the B-phase coil and the C-phase coil includes a connecting portion that extends along the other cylindrical portion in the axial direction between the teeth which are spaced apart in the circumferential direction. The total number of turns of the A-phase coil is 2 turns less than the total number of turns of the B-phase coil and the total number of turns of the C-phase coil. A stator characterized in that each of the four teeth around which the A-phase coil is wound has a diagonal wire between the tooth and the tooth adjacent to the tooth in the circumferential direction, connecting the A-phase coil and the connecting portion, and each wire functions as a coil of 0.5 turns.

2. In the stator according to claim 1, The A-phase coil is A first A-phase coil wound in series around two teeth spaced apart in the circumferential direction, A second A-phase coil, wound in series around two other teeth spaced apart in the circumferential direction, is connected in parallel with the second A-phase coil. The aforementioned B-phase coil is A first B-phase coil wound in series around two teeth spaced apart in the circumferential direction, A second B-phase coil, wound in series around two other teeth spaced apart in the circumferential direction, is connected in parallel with the second B-phase coil. The C-phase coil is A first C-phase coil is wound in series around two teeth spaced apart in the circumferential direction, A second C-phase coil, wound in series around two other teeth spaced apart in the circumferential direction, is connected in parallel with the second C-phase coil. The total number of turns of the first A-phase coil is one turn less than the total number of turns of the first B-phase coil and the total number of turns of the first C-phase coil. A stator characterized in that the total number of turns of the second A-phase coil is one turn less than the total number of turns of the second B-phase coil and the total number of turns of the second C-phase coil.

3. In the stator according to claim 1, A stator characterized in that the B-phase coil and the C-phase coil pass radially outside the connecting portion of the A-phase coil.

4. Motor bracket and A shaft fixed to one side in the thickness direction of the motor bracket, The stator according to claim 1, wherein the cylindrical portion is fixed to the motor bracket so as to surround the shaft, A rotor comprising a rotor yoke rotatably supported on the shaft, and a plurality of permanent magnets supported on the rotor yoke and spaced apart in the circumferential direction so as to surround the stator, A motor comprising a driver circuit disposed on the other side in the thickness direction of the motor bracket, which generates a magnetic field in the coil for rotating the rotor, The connecting portion of the A-phase coil extends along the cylindrical portion on the motor bracket side from the teeth, The motor is characterized in that the connecting portions of the B-phase coil and the C-phase coil each extend from the teeth along the cylindrical portion on the side opposite to the motor bracket.

5. In the motor according to claim 4, The twelve teeth are arranged circumferentially as the first tooth, second tooth, third tooth, fourth tooth, fifth tooth, sixth tooth, seventh tooth, eighth tooth, ninth tooth, tenth tooth, eleventh tooth, and twelfth tooth, The A-phase coil is A first A-phase coil is wound from the driver circuit around the third tooth, across the motor bracket side from the tooth, around the eighth tooth, and returns to the driver circuit. It includes a second A-phase coil that is wound from the driver circuit around the ninth tooth, across the motor bracket side from the tooth, around the second tooth, and returns to the driver circuit, The aforementioned B-phase coil is A first B-phase coil is wound from the driver circuit around the fifth tooth, then across from the tooth to the motor bracket on the opposite side, and wound around the tenth tooth, returning to the driver circuit. It includes a second B-phase coil that is wound from the driver circuit around the 11th tooth, across the tooth to the opposite side of the motor bracket, around the 4th tooth, and returns to the driver circuit. The C-phase coil is A first C-phase coil is wound from the driver circuit around the first tooth, then across from the tooth to the motor bracket on the opposite side, and wound around the sixth tooth, returning to the driver circuit. A motor characterized by including a second C-phase coil that is wound from the driver circuit around the seventh tooth, and then wound from the tooth across to the opposite side of the motor bracket around the twelfth tooth, returning to the driver circuit.

6. The motor according to claim 4, A fan device characterized by comprising a fan that is rotationally driven by the aforementioned motor to generate cooling air.

7. In the method for winding a coil for a stator according to claim 1, The A-phase coil is wound around the aforementioned, After winding the A-phase coil, wind the B-phase coil and the C-phase coil, A coil winding method characterized by winding the B-phase coil and the C-phase coil, and then positioning the portions of the A-phase coil, the B-phase coil, and the C-phase coil that are connected to the respective driver circuits.

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