Motor device, power tool, and coating method

Abstract

Provided is a technology capable of reducing the cost of a motor device. A motor device comprises a case, a motor, an intermediate part, and a clay-like heat conduction member. The motor includes a plurality of coils including a first coil and a second coil. The intermediate part is located between the first coil and the second coil. The heat conduction member is located between the first coil and the case.

Description

Motor device, power tool, and coating method

[0001] The present disclosure relates to a motor device.

[0002] Patent Documents 1 and 2 disclose technologies related to motor devices.

[0003] Japanese Patent Application Laid-Open No. 2021-69196, Japanese Patent Application Laid-Open No. 2023-137964

[0004] A motor device, a power tool, and a coating method are disclosed. In one embodiment, the motor device includes a case, a motor, an intermediate portion, and a clay-like heat conductive member. The motor has a plurality of coils including a first coil and a second coil. The intermediate portion is located between the first coil and the second coil. The heat conductive member is located between the first coil and the case.

[0005] Also, in one embodiment, the power tool includes the above-described motor device and a drive portion driven by the motor device.

[0006] Also, in one embodiment, the coating method coats a clay-like heat conductive member on a first coil end of a first coil included in the motor included in the above-described motor device.

[0007] Figure 1 is a schematic diagram showing an example of a motor device. Figure 2 is a schematic diagram showing an example of a motor device. Figure 3 is a schematic diagram showing an example of a motor device. Figure 4 is a schematic diagram showing an example of a motor device. Figure 5 is a schematic diagram showing an example of a stator. Figure 6 is a schematic diagram showing an example of a stator. Figure 7 is a schematic diagram showing an example of a stator. Figure 8 is a schematic diagram showing an example of a stator. Figure 9 is a schematic diagram showing an example of a stator. Figure 10 is a schematic diagram showing an example of a stator. Figure 11 is a schematic diagram showing an example of a stator. Figure 12 is a schematic diagram showing an example of a stator. Figure 13 is a schematic diagram showing an example of a stator. Figure 14 is a schematic diagram showing an example of a stator. Figure 15 is a schematic diagram showing an example of a coil connection method. Figure 16 is a schematic diagram showing an example of a coil connection method. Figure 17 is a schematic diagram showing an example of a coil connection method. Figure 18 is a schematic diagram showing an example of a coil connection method. Figure 19 is a schematic diagram showing an example of a heat conductive material application method. Figure 20 is a schematic diagram showing an example of a heat conductive material application method. Figure 21 is a schematic diagram showing an example of how a heat conductive material is applied to a coil. Figure 22 is a schematic diagram showing an example of how to apply the heat conductive material. Figure 23 is a schematic diagram showing an example of how to apply the heat conductive material. Figure 24 is a schematic diagram showing an example of how to apply the heat conductive material. Figure 25 is a schematic diagram showing an example of a stator. Figure 26 is a schematic diagram showing an example of a substrate. Figure 27 is a schematic diagram showing an example of a stator. Figure 28 is a schematic diagram showing an example of a stator. Figure 29 is a schematic diagram showing an example of a stator. Figure 30 is a schematic diagram showing an example of a stator. Figure 31 is a schematic diagram showing an example of how to apply the heat conductive material. Figure 32 is a schematic diagram showing an example of a power tool. Figure 33 is a schematic diagram showing an example of a power supply device.

[0008] Figures 1 to 3 are schematic diagrams showing an example of the motor device 1. Figures 1 to 3 show the motor device 1 viewed from different angles. Figure 4 is a schematic diagram showing an example of the cross-sectional structure along the line A-A in Figure 3.

[0009] As shown in Figures 1 to 4, the motor device 1 comprises, for example, a case (also called a motor case) 2, a motor (also called a motor body) 3, a motor shaft 4 attached to the motor 3, a substrate 5, and a heat conductive member 6. The motor 3, substrate 5, and heat conductive member 6 are located inside the case 2.

[0010] Case 2, for example, has thermal conductivity. Case 2 is composed of a material with high thermal conductivity. Case 2 may be composed of a metal such as aluminum, or of other materials. Case 2 can also be described as a thermal conductive member.

[0011] Case 2 comprises, for example, a first case 2a, a second case 2b, and a third case 2c. The first case 2a is, for example, cylindrical. The first case 2a surrounds the outer circumference of the motor 3 along the direction of rotation of the motor 3. The second case 2b covers, for example, the entire opening of one side of the cylindrical first case 2a. The third case 2c covers, for example, the peripheral end of the other opening of the first case 2a, as shown in Figure 2, etc. The central part of the third case 2c is open. The first case 2a can also be called, for example, an inner case or case body. The second case 2b and the third case 2c can also be called, for example, lid cases or lid members. The second case 2b and the third case 2c are fixed to the first case 2a with, for example, a plurality of screws 8, as shown in Figure 1, etc. Hereafter, for convenience of explanation, in the motor device 1, the side of the second case 2b may be referred to as the upper side, and the side of the third case 2c may be referred to as the lower side.

[0012] Motor 3 is, for example, a brushless DC motor. Motor 3 may be something other than a brushless DC motor. Motor 3 comprises, for example, a rotor 10 and a stator 11. The rotor 10 and stator 11 are, for example, annular. The stator 11 surrounds the outer circumference of the rotor 10 along the direction of rotation of the rotor 10. The rotor 10 can be said to be located inside the stator 11, or it can be said to be located within the hollow part of the stator 11. The motor shaft 4 passes through the hollow part of the rotor 10. The rotor 10 is fixed to the motor shaft 4. The motor shaft 4 rotates in accordance with the rotation of the rotor 10. When the motor device 1 is used, a drive unit driven by the motor device 1 is connected to the motor shaft 4.

[0013] Figure 5 is a schematic diagram showing an example of a stator 11 and a substrate 5. Figures 6 and 7 are schematic diagrams showing an example of a stator 11. Figure 6 shows an example of a view of the stator 11 from above, and Figure 7 shows an example of a view of the stator 11 from below.

[0014] As shown in Figures 4-7, the stator 11 comprises, for example, a stator core 12 and N coils 13 (where N is an integer of 2 or more) wound around the stator core 12. The stator core 12 (also simply called the core 12) is, for example, annular. The core 12 surrounds the outer circumference of the rotor 10 along the direction of rotation of the rotor 10. The N coils 13 are wound around the core 12 so as to surround the outer circumference of the rotor 10 along the direction of rotation of the rotor 10. The N coils 13 are arranged along the circumferential direction of the core 12, in other words, along the direction of rotation of the rotor 10.

[0015] In the examples shown in Figures 4-7, N = 6, and 6 coils 13 are wound around the core 12. The stator core 12 and rotor 10 are made of a metal such as iron. For example, the stator core 12 and rotor 10 may be made of electromagnetic steel sheet. The coils 13 are made of magnet wire, for example, copper wire coated with an insulating film. The coils and magnet wire can also be called electric wires.

[0016] The first case 2a surrounds the outer circumference of the stator 11 along the circumferential direction of the stator 11. The first case 2a surrounds the outer circumference of the annular core 12 along the circumferential direction of the core 12. It can also be said that the first case 2a surrounds the outer circumference of the stator 11 or the core 12 along the rotational direction of the rotor 10 or the rotational direction of the motor shaft 4. The first case 2a is in contact with the outer circumferential surface of the stator 11. More specifically, the first case 2a is in contact with the outer circumferential surface of the core 12.

[0017] Multiple lead wires 9 are connected to the motor 3, which transmit the drive voltage for driving the motor 3. These lead wires can also be described as electrical wires. The motor 3 is, for example, a three-phase motor and is driven by an inverter circuit. The multiple lead wires 9 consist of three lead wires 9a, 9b, and 9c, each transmitting the three-phase drive voltage output by the inverter circuit. The lead wires 9a, 9b, and 9c are connected to the stator 11. At least two coils 13 are connected to the stator 11. Furthermore, each of the lead wires 9a, 9b, and 9c is connected to at least one coil 13. A detailed example of the stator 11 configuration will be described later.

[0018] The substrate 5 is, for example, a circuit board on which circuits are formed. The substrate 5 is, for example, plate-shaped and annular. A sensor for detecting the rotational position of the rotor 10 is mounted on the substrate 5. The substrate 5 can also be called a sensor substrate. The substrate 5 is attached to the stator 11, for example. The substrate 5 is located above the rotor 10, the stator core 12, and the plurality of coils 13 (in other words, on the second case 2b side). In the rotational axis direction of the motor 3, the substrate 5 faces the N coils 13 arranged in an annular shape with a gap between them. The rotational axis direction can also be said to be the direction in which the rotation axis extends. The rotational axis direction of the motor 3 can also be said to be the rotational axis direction of the rotor 10, or the rotational axis direction of the motor shaft 4.

[0019] Hereafter, when we simply refer to the rotation axis direction or axis direction, we mean the rotation axis direction of the motor 3 (in other words, the rotation axis direction of the rotor 10 or the rotation axis direction of the motor shaft 4). Also, when we simply refer to the circumferential direction in the description of the stator 11, we mean the circumferential direction of the stator 11. The circumferential direction of the stator 11 can also be said to be the direction around the rotation axis direction.

[0020] Multiple lead wires 5a (for example, five lead wires 5a) are connected to the circuit board 5. These lead wires 5a can also be called wiring. The output signal (also called the sensor signal) of the sensor mounted on the circuit board 5 is output to the outside of the motor device 1 via some of the multiple lead wires 5a. In addition, the power supply for the sensor mounted on the circuit board 5 is supplied to the circuit board 5 from outside the motor device 1 via some of the multiple lead wires 5a.

[0021] The heat conductive member 6 is located, for example, between the coil 13 and the case 2. The heat conductive member 6 is located, for example, between each of the N coils 13 and the case 2. The heat conductive member 6 is in contact with each coil 13 and the inner surface of the case 2.

[0022] The heat conductive member 6 may be, for example, clay-like. The thermal conductivity of the heat conductive member 6 may be 2.5 W / m·K or higher, 3 W / m·K or higher, 3.5 W / m·K or higher, 4 W / m·K or higher, or 4.5 W / m·K or higher. The thermal conductivity of the heat conductive member 6 and other members may be measured, for example, by the hot-wire method.

[0023] The impurity consistency, which represents the hardness of the clay-like heat conductive member 6, may be in the range of 100 or more and 250 or less. The impurity consistency of members such as the heat conductive member 6 may be measured according to, for example, "JIS K2220". The heat conductive member 6 may also be an electrically insulating member.

[0024] The heat generated in the coil 13 is transferred to the case 2, for example, through the heat conductive member 6. The heat transferred to the case 2 is then released from the case 2 to the outside. As a result, the heat generated in the coil 13 is released to the outside of the motor device 1, and the coil 13 does not overheat easily. The thermal conductivity of the case 2 may be greater than, for example, the thermal conductivity of the heat conductive member 6.

[0025] Because the heat conductive member 6 is clay-like, it adheres well to the uneven surface of the coil 13. Therefore, the heat generated by the coil 13 can be appropriately transferred to the heat conductive member 6. Furthermore, even if there are irregularities in the area on the inner surface of the case 2 where the heat conductive member 6 makes contact, the heat conductive member 6 adheres well to that area. Therefore, heat can be appropriately transferred from the heat conductive member 6 to the case 2. As a result, the heat dissipation characteristics for the heat generated by the coil 13 are improved, and the coil 13 becomes less likely to overheat.

[0026] Furthermore, if the motor device 1 is used with the space inside the case 2 sealed, for example by using an oil seal, it is not possible to blow air onto the coil 13 from the outside of the motor device 1, for example, from a fan. In this way, even when the motor device 1 is used with the space inside the case 2 sealed, the heat generated in the coil 13 can be released to the outside of the motor device 1 through the heat conductive member 6 and the case 2. Therefore, even when the motor device 1 is used with the space inside the case 2 sealed, the coil 13 is less likely to overheat. Note that the motor 3 does not necessarily have to be equipped with the heat conductive member 6. Also, the heat conductive member 6 does not necessarily have to be clay-like.

[0027] <Example of Stator Configuration> Figure 8 is a schematic diagram showing an example of a stator 11 and a circuit board 5. Figures 9 and 10 are schematic diagrams showing an example of a stator 11. Figure 9 shows an example of the stator 11 viewed from diagonally above, and Figure 10 shows an example of the stator 11 viewed from diagonally below. In Figures 8 to 10, for the sake of explanation, unlike Figures 5 to 7, the multiple lead wires 9, the multiple lead wires 5a, the connections between the coils 13, the connections between the coils 13 and the lead wires 9, and the jumper wires of the coils 13 are not shown.

[0028] As shown in Figures 5 to 10, the stator 11 includes, in addition to the core 12 and N coils 13, a first insulating member 21, a second insulating member 22, and N third insulating members 23. The first insulating member 21, the second insulating member 22, and the third insulating members 23 are members for insulating the core 12 and the coils 13 from each other.

[0029] The first insulating member 21 is attached to the upper side of the core 12, and the second insulating member 22 is attached to the lower side of the core 12. The core 12 is sandwiched in the axial direction by the first insulating member 21 and the second insulating member 22. N third insulating members 23 are each placed in the N slots 120 of the core 12, which will be described later. N coils 13 are wound around the core 12 over the first insulating member 21, the second insulating member 22, and the N third insulating members 23. Hereafter, the first insulating member 21 may be referred to as the upper insulating member 21, and the second insulating member 22 may be referred to as the lower insulating member 22.

[0030] Figure 11 is a schematic diagram showing an example of a core 12, an upper insulating member 21, and a lower insulating member 22. In Figure 11, the core 12, the upper insulating member 21, and the lower insulating member 22 are shown separated from each other.

[0031] The core 12 has N slots 120 arranged in the circumferential direction. The core 12 also has N teeth 121 arranged in the circumferential direction. The space between two adjacent teeth 121 in the circumferential direction constitutes a slot 120. N coils 13 are wound around each of the N teeth 121. Hereafter, when simply referred to as the winding axis direction, it means the winding axis direction of the coil 13. The winding axis direction of the coil 13 can also be said to be the direction perpendicular to the winding direction of the coil 13. Furthermore, the winding axis direction of the coil 13 can also be said to be the direction along the radial direction from the center of the stator 11 toward the coil 13.

[0032] Each coil 13 has a coil end 131 (also called the upper coil end 131) that protrudes above (in other words, to one side of) the rotor 10, and a coil end 132 (also called the lower coil end 132) that protrudes below (in other words, to the other side of) the rotor 10. The upper coil end 131 of a coil 13 wound around teeth 121 protrudes above teeth 121. The lower coil end 132 of a coil 13 wound around teeth 121 protrudes below teeth 121. The upper coil end 131 and the lower coil end 132 sandwich teeth 121 in the axial direction (in other words, vertical direction). The upper coil end 131 is located at the upper end of the coil 13 in the axial direction, and the lower coil end 132 is located at the lower end of the coil 13 in the axial direction. The upper coil end 131 can be said to constitute the upper axial end of the coil 13, and the lower coil end 132 can be said to constitute the lower axial end of the coil 13.

[0033] Furthermore, each coil 13 has a pair of coil sides 133 (see Figure 14, described later) that face the rotor 10 in the winding axis direction. Each of the pair of coil sides 133 is connected to an upper coil end 131 and a lower coil end 132. The pair of coil sides 133 of a coil 13 wound around teeth 121 are located in two slots 120 located on both sides of teeth 121 in the circumferential direction. The pair of coil sides 133 face each other on a pair of circumferential sides of teeth 121. The pair of coil sides 133 of a coil 13 are located on a pair of circumferential sides of the coil 13. It can also be said that the pair of coil sides 133 of a coil 13 are located on a pair of circumferential sides of the coil 13 in the direction of rotation of the motor 3.

[0034] The upper insulating member 21 is made of, for example, a resin molded product. The upper insulating member 21 insulates the upper coil ends 131 of the N coils 13 from the core 12. The upper insulating member 21 is also called, for example, an end insulator. For each of the N coils 13, the upper insulating member 21 has an insulating portion 211 that insulates the teeth 121 around which the coil 13 is wound from the upper coil end 131 of the coil 13. The insulating portion 211 is located on the upper surface of the teeth 121. The insulating portion 211 is located between the upper surface of the teeth 121 and the upper coil end 131 of the coil 13 wound around the teeth 121. The coil 13 is wound over the teeth 121 from above the insulating portion 211. Hereafter, the insulating portion 211 may be referred to as the upper insulating portion 211.

[0035] The upper insulating member 21 has an inner wall portion 212 and an outer wall portion 213 connected to each upper insulating portion 211. The inner wall portion 212 is connected to the inner diameter side end of the upper insulating portion 211 of the stator 11. The inner diameter side of the stator 11 can also be called the inner circumference side of the stator 11, the inner diameter side of the core 12, the inner circumference side of the core 12, or the rotor 10 side. The inner wall portion 212 is located on the upper surface of the teeth 121 and protrudes upward from the inner diameter side end of the upper insulating portion 211 of the stator 11. The inner wall portion 212 is located on the inner diameter side of the stator 11 from the upper insulating portion 211. Hereafter, the inner wall portion 212 may be referred to as the upper inner wall portion 212. Also, simply saying "inner diameter side" means the inner diameter side of the stator 11.

[0036] The outer wall portion 213 is connected to the outer diameter side end of the upper insulating portion 211 of the stator 11. The outer diameter side of the stator 11 can also be called the outer circumference side of the stator 11, the outer diameter side of the core 12, or the outer circumference side of the core 12. The outer wall portion 213 is located on the upper surface of the teeth 121 and protrudes upward from the outer diameter side end of the upper insulating portion 211 of the stator 11. The outer wall portion 213 is located on the outer diameter side of the stator 11 from the upper insulating portion 211. Hereafter, the outer wall portion 213 may be referred to as the upper outer wall portion 213. Also, simply saying "outer diameter side" means the outer diameter side of the stator 11.

[0037] The lower insulating member 22 is made of, for example, a resin molded product. The lower insulating member 22 insulates the lower coil ends 132 of the N coils 13 from the core 12. The lower insulating member 22 is also called, for example, an end insulator. For each of the N coils 13, the lower insulating member 222 has an insulating portion 221 that insulates the teeth 121 around which the coil 13 is wound from the lower coil end 132 of the coil 13. The insulating portion 221 is located on the lower surface of the teeth 121. The insulating portion 221 is located between the lower surface of the teeth 121 and the lower coil end 132 of the coil 13 wound around the teeth 121. The coil 13 is wound around the teeth 121 from above the insulating portion 221. It can also be said that the coil 13 is wound around the portion consisting of the teeth 121, the insulating portion 211 on the upper surface of the teeth 121, and the insulating portion 221 on the lower surface of the teeth 121. Hereafter, the insulating portion 221 may be referred to as the lower insulating portion 221.

[0038] The lower insulating member 22 has an inner wall portion 222 and an outer wall portion 223 connected to each lower insulating portion 221. The inner wall portion 222 is connected to the inner diameter end of the lower insulating portion 221. The inner wall portion 222 is located on the lower surface of the teeth 121 and protrudes downward from the inner diameter end of the lower insulating portion 221. The inner wall portion 222 is located on the inner diameter side of the lower insulating portion 221. Hereafter, the inner wall portion 222 may be referred to as the lower inner wall portion 222.

[0039] The outer wall portion 223 is connected to the outer diameter end of the lower insulating portion 221. The outer wall portion 223 is located on the lower surface of the teeth 121 and protrudes downward from the outer diameter end of the lower insulating portion 221. The outer wall portion 223 is located on the outer diameter side of the lower insulating portion 221. Hereafter, it may be referred to as the outer wall portion 223 or the lower outer wall portion 223.

[0040] In the following, the tooth 121 being described (in other words, the tooth 121 of interest) will be referred to as the target tooth 121. The upper insulating portion 211 on the upper surface of the target tooth 121 will be referred to as the target upper insulating portion 211. The lower insulating portion 221 on the lower surface of the target tooth 121 will be referred to as the target lower insulating portion 221. The coil 13 wound around the target tooth 121 will be referred to as the target coil 13.

[0041] The upper inner wall portion 212 on the upper surface of the target tooth 121 is located on the inner diameter side of the upper coil end 131 of the target coil 13. The upper inner wall portion 212 on the upper surface of the target tooth 121 faces the inner diameter side region of the upper coil end 131 of the target coil 13. Because the upper insulating member 21 has an upper inner wall portion 212, when the coil 13 is wound around the upper insulating portion 211 and the tooth 121, the position of the coil 13 is less likely to shift inward of the tooth 121. Therefore, it becomes easier to properly wind the coil 13 around the tooth 121.

[0042] The upper outer wall portion 213 on the upper surface of the target tooth 121 is located on the outer diameter side of the upper coil end 131 of the target coil 13. The upper outer wall portion 213 on the upper surface of the target tooth 121 faces the region on the outer diameter side of the upper coil end 131 of the target coil 13. Since the upper insulating member 21 has the upper outer wall portion 213, when the coil 13 is wound around the upper insulating portion 211 and the tooth 121, the position of the coil 13 is less likely to shift to the outer diameter side than the tooth 121. Therefore, it becomes easier to appropriately wind the coil 13 around the tooth 121.

[0043] The lower inner wall portion 222 on the lower surface of the target tooth 121 is located on the inner diameter side of the lower coil end 132 of the target coil 13. The lower inner wall portion 222 on the lower surface of the target tooth 121 faces the region on the inner diameter side of the lower coil end 132 of the target coil 13. Since the lower insulating member 22 has the lower inner wall portion 222, when the coil 13 is wound around the lower insulating portion 221 and the tooth 121, the coil 13 is less likely to shift to the inner diameter side than the tooth 121. Therefore, it becomes easier to appropriately wind the coil 13 around the tooth 121.

[0044] The lower outer wall portion 223 on the lower surface of the target tooth 121 is located on the outer diameter side of the lower coil end 132 of the target coil 13. The lower outer wall portion 223 on the lower surface of the target tooth 121 faces the region on the outer diameter side of the lower coil end 132 of the target coil 13. Since the lower insulating member 22 has the lower outer wall portion 223, when the coil 13 is wound around the lower insulating portion 221 and the tooth 121, the position of the coil 13 is less likely to shift to the outer diameter side than the tooth 121. Therefore, it becomes easier to appropriately wind the coil 13 around the tooth 121.

[0045] For each of the N upper outer wall portions 213 of the upper insulating member 21, the first columnar portion 214 and the second columnar portion 215 that are connected to the upper outer wall portion 213 and protrude above the upper outer wall portion 213 are provided. The first columnar portion 214 and the second columnar portion 215 connected to the upper outer wall portion 213 are located on the outer diameter side of the upper outer wall portion 213.

[0046] For each of the N lower outer wall portions 223 of the lower insulating member 22, it has a first columnar portion 224 and a second columnar portion 225 that are connected to the lower outer wall portion 223 and protrude downward from the lower outer wall portion 223. The first columnar portion 224 and the second columnar portion 225 connected to the lower outer wall portion 223 are located on the outer diameter side of the lower outer wall portion 223.

[0047] As shown in FIGS. 4, 5, 8, etc., the substrate 5 is attached to the upper insulating member 21, for example. The first columnar portion 214 of the upper insulating member 21 is inserted into a through hole provided in the substrate 5. The second columnar portion 215 of the upper insulating member 21 supports the substrate 5. For example, at least one of the N first columnar portions 214 provided in the upper insulating member 21 is inserted into the through hole of the substrate 5 such that its tip protrudes from the substrate 5, and then the tip is crushed, thereby fixing the substrate 5 to the upper insulating member 21. Note that the method of attaching the substrate 5 to the upper insulating member 21 is not limited to this.

[0048] The third insulating member 23 is, for example, a sheet-like member. The N third insulating members 23 provided in the stator 11 are respectively arranged in the N slots 120 provided in the core 12. The third insulating member 23 is also called a slot insulator, for example. Hereinafter, the sheet-like third insulating member 23 may be referred to as an insulating sheet 23.

[0049] FIGS. 12 and 13 are schematic views showing an example of how the core 12, the upper insulating member 21, the lower insulating member 22, and the N insulating sheets 23 are seen from below. In FIGS. 12 and 13, an example of how the core 12, etc. are seen from different angles is shown. In FIG. 13, a state where one of the N insulating sheets 23 is taken out from the slot 120 is shown. FIG. 14 is a schematic view showing an example of simplifying the cross-sectional structure taken along the arrow B - B shown in FIG. 12. In FIG. 14, for convenience of explanation, the teeth 121 of the core 12, the upper insulating portion 211 of the upper insulating member 21, the lower insulating portion 221 of the lower insulating member 22, and the cross-section of the insulating sheet 23 are shown in a simplified manner. Also, in FIG. 14, for convenience of explanation, the coil 13 wound around the teeth 121 is shown by a dashed line.

[0050] Hereafter, the slot 120 being described may be referred to as the target slot 120. The insulating sheet 23 placed in the target slot 120 may be referred to as the target insulating sheet 23. The two teeth 121 that define the target slot 120 and are arranged in the circumferential direction may be referred to as the target first tooth 121 and the target second tooth 121, respectively. The coil 13 wound around the target first tooth 121 may be referred to as the target first coil 13. The coil 13 wound around the target second tooth 121 may be referred to as the target second coil 13.

[0051] Furthermore, of the two circumferentially opposing sides of the target first tooth 121, the side facing the target second tooth 121 is sometimes called the target first side. Also, of the two circumferentially opposing sides of the target second tooth 121, the side facing the target first tooth 121 is sometimes called the target second side. The space between the target first side and the target second side constitutes the target slot 120. Furthermore, the coil side 133 of the coil 13 wound around the target first tooth that faces the target second tooth is called the target first coil side 133. Also, the coil side 133 of the coil 13 wound around the target second tooth that faces the target first tooth is called the target second coil side 133. The target first coil side 133 and the target second coil side 133 are located within the target slot 120.

[0052] The target insulating sheet 23 is placed in the target slot 120 in a folded state according to the shape of the target slot 120. As shown in Figures 12 and 13, the target insulating sheet 23 includes, for example, a first insulating portion 230 that insulates the target first tooth 121 from the target first coil side 133, and a second insulating portion 230 that insulates the target second tooth 121 from the target second coil side 133. The target first coil 13 is wound around the target first tooth 121 over the first insulating portion 230. The target second coil 13 is wound around the target second tooth 121 over the second insulating portion 230.

[0053] The first insulating portion 230 insulates the target first side surface of the target first tooth 121 from the target first coil side 133. The first insulating portion 230 is located between the target first side surface of the target first tooth 121 and the target first coil side 133. The second insulating portion 230 insulates the target second side surface of the target second tooth 121 from the target second coil side 133. The second insulating portion 230 is located between the target second side surface of the target second tooth 121 and the target second coil side 133.

[0054] When the stator 11 is assembled, for example, after the upper insulating member 21 and the lower insulating member 22 are attached to the core 12, N insulating sheets 23 are inserted into the N slots 120 of the core 12. The insulating sheets 23 are inserted into the slots 120 from below, for example, as shown in Figure 13.

[0055] In this example, as shown in Figure 14, the lower insulating portion 221 provided on the target tooth 121 protrudes more from the target tooth 121 towards the coil side 133 of the target coil 13 in the circumferential direction (in other words, in the rotation direction of the motor 3) than from the target tooth 121. As a result, when the insulating sheet 23 is inserted into the slot 120 from below, the insulating sheet 23 is less likely to interfere with the tooth 121. Consequently, it becomes easier to insert the insulating sheet 23 into the slot 120 from below.

[0056] Furthermore, in this example, as shown in Figure 14, the upper insulating portion 211 provided on the target tooth 121 does not protrude further than the target tooth 121 toward the coil side 133 of the target coil 13 in the circumferential direction (in other words, in the rotation direction of the motor 3). As a result, when the insulating sheet 23 is inserted into the slot 120 from below and moves upward, the insulating sheet 23 is less likely to interfere with the upper insulating portion 211. Consequently, it becomes easier to insert the insulating sheet 23 into the slot 120 from below.

[0057] The insulating sheet 23 may also be inserted into the slot 120 from above. In this case, the upper insulating portion 211 provided on the target tooth 121 may protrude in the circumferential direction from the target tooth 121 towards the coil side 133 of the target coil 13. This makes it less likely for the insulating sheet 23 to interfere with the tooth 121 when it is inserted into the slot 120 from above. As a result, it becomes easier to insert the insulating sheet 23 into the slot 120 from above. Furthermore, the lower insulating portion 221 provided on the target tooth 121 does not have to protrude in the circumferential direction from the target tooth 121 towards the coil side 133 of the target coil 13. This makes it less likely for the insulating sheet 23 to interfere with the lower insulating portion 221 when it is inserted into the slot 120 from above and moves downwards. As a result, it becomes easier to insert the insulating sheet 23 into the slot 120 from above.

[0058] The upper insulating member 21 may, for example, have thermal conductivity. That is, each upper insulating part 211 may have thermal conductivity. In such a case, the upper insulating member 21 may be made of a resin containing silica or alumina, for example. That is, each upper insulating part 211 may be made of a resin containing silica or alumina, for example. Furthermore, the thermal conductivity of the upper insulating member 21 may be, for example, 1.2 W / m·K or higher. That is, the thermal conductivity of each upper insulating part 211 may be, for example, 1.2 W / m·K or higher.

[0059] If the upper insulating portion 211 that insulates the target teeth 121 from the upper coil end 131 of the target coil 13 has thermal conductivity, the heat generated in the target coil 13 is more easily transferred to the target teeth 121 through the upper insulating portion 211. The heat transferred to the target teeth 121 is then released to the outside of the case 2 through the first case 2a in contact with the core 12. As a result, the target coil 13 becomes less likely to overheat.

[0060] The lower insulating member 22 may, for example, have thermal conductivity. That is, each lower insulating part 221 may have thermal conductivity. In such a case, the lower insulating member 22 may be made of a resin containing, for example, silica or alumina. Furthermore, the thermal conductivity of the lower insulating member 22 may be, for example, 1.2 W / m·K or higher.

[0061] If the lower insulating portion 221 that insulates the target teeth 121 from the lower coil end 132 of the target coil 13 has thermal conductivity, the heat generated in the target coil 13 is more easily transferred to the target teeth 121 through the lower insulating portion 221. The heat transferred to the target teeth 121 is then released to the outside of the case 2 through the first case 2a in contact with the core 12. As a result, the target coil 13 becomes less likely to overheat.

[0062] The insulating sheet 23 may, for example, have thermal conductivity. In this case, each insulating portion 230 of the insulating sheet 23 will have thermal conductivity. If the insulating sheet 23 has thermal conductivity, it may be made of a resin containing, for example, silica or alumina. The thermal conductivity of the insulating sheet 23 may be, for example, 1.2 W / m·K or higher.

[0063] If the insulating portion 230 that insulates the target teeth 121 from the coil side 133 of the target coil 13 has thermal conductivity, the heat generated in the target coil 13 is more easily transferred to the target teeth 121 through the insulating portion 230. The heat transferred to the target teeth 121 is then released to the outside of the case 2 through the first case 2a in contact with the core 12. As a result, the target coil 13 becomes less likely to overheat.

[0064] Furthermore, the thermal conductivity of the heat conduction member 6 may be greater than that of the thermally conductive upper insulating member 21. Also, the thermal conductivity of the heat conduction member 6 may be greater than that of the thermally conductive lower insulating member 22. Furthermore, the thermal conductivity of the heat conduction member 6 may be greater than that of the thermally conductive insulating sheet 23.

[0065] <Example of connection method for multiple coils> Figure 15 is a schematic diagram showing an example of a connection method for multiple coils 13 that have a stator 11. In the example of Figure 15, the connection of the multiple coils 13 (also simply called coil connection) is, for example, a series Y connection.

[0066] N coils 13 (6 coils 13 in this example) are composed of, for example, a first U-phase coil 13Ua, a second U-phase coil 13Ub, a first V-phase coil 13Va, a second V-phase coil 13Vb, a first W-phase coil 13Wa, and a second W-phase coil 13Wb. As shown in Figures 6 and 7, the first U-phase coil 13Ua, the first V-phase coil 13Va, the first W-phase coil 13Wa, the second U-phase coil 13Ub, the second V-phase coil 13Vb, and the second W-phase coil 13Wb are arranged in this order along the circumferential direction. The first U-phase coil 13Ua and the second U-phase coil 13Ub are connected in series with each other. The first V-phase coil 13Va and the second V-phase coil 13Vb are connected in series with each other. The first W-phase coil 13Wa and the second W-phase coil 13Wb are connected in series with each other.

[0067] One end of the first U-phase coil 13Ua is connected to lead wire 9a, and the other end of the first U-phase coil 13Ua is connected to one end of the second U-phase coil 13Ub. One end of the first V-phase coil 13Va is connected to lead wire 9b, and the other end of the first V-phase coil 13Va is connected to one end of the second V-phase coil 13Vb. One end of the first W-phase coil 13Wa is connected to lead wire 9c, and the other end of the first W-phase coil 13Wa is connected to one end of the second W-phase coil 13Wb. The other end of the second U-phase coil 13Ub, the other end of the second V-phase coil 13Vb, and the other end of the second W-phase coil 13Wb are connected to each other. The connection point between the other end of the second U-phase coil 13Ub, the other end of the second V-phase coil 13Vb, and the other end of the second W-phase coil 13Wb is also called the neutral point.

[0068] The stator 11 has a connection section CU1 where lead wire 9a is connected to the first U-phase coil 13Ua, and a connection section CU2 where the first U-phase coil 13Ua is connected to the second U-phase coil 13Ub. The stator 11 has a connection section CV1 where lead wire 9b is connected to the first V-phase coil 13Va, and a connection section CV2 where the first V-phase coil 13Va is connected to the second V-phase coil 13Vb. The stator 11 has a connection section CW1 where lead wire 9c is connected to the first W-phase coil 13Wa, and a connection section CW2 where the first W-phase coil 13Wa is connected to the second W-phase coil 13Wb. The stator 11 has a connection section CC to which the second U-phase coil 13Ub, the second V-phase coil 13Vb, and the second W-phase coil 13Wb are connected. Figures 6 and 7 above show the connection sections CU1, CU2, CV1, CV2, CW1, CW2, and CC.

[0069] A connection section, such as connection sections CU1 and CU2, in which multiple wires are connected, includes, for example, a splice terminal 30 (see Figure 7) for connecting multiple wires and an insulating tube 31 (see Figure 7) covering the splice terminal 30. The splice terminal 30 is made of, for example, metal and electrically connects multiple wires. The insulating tube 31 may be a varnished tube in which an insulating varnish is applied to an insulating sleeve made of, for example, polyester. In addition, in the connection section, the insulating tube 31 may be placed over the soldered joints where the multiple wires are soldered together.

[0070] In this example, the stator 11 has an intermediate section (also called an inter-coil intermediate section) located between two coils 13 that are adjacent to each other in the circumferential direction (also called an inter-coil section). The stator 11 has N inter-coil intermediate sections, each located within one of the N slots 120. The inter-coil intermediate section can also be described as being located in the gap (also called an inter-coil gap) between two coils 13 that are adjacent to each other in the circumferential direction.

[0071] The intermediate portion between coils includes, for example, at least a portion of the connection portion. The connection portion has a portion located between coils. A portion of the connection portion may be located between coils, or the entirety of the connection portion may be located between coils.

[0072] In the examples of Figures 6 and 7, at least a portion of the connection section CU1 is located between the first U-phase coil 13Ua and the first V-phase coil 13Va. The intermediate section between the coils located between the first U-phase coil 13Ua and the first V-phase coil 13Va includes at least a portion of the connection section CU1. The connection section CU1 is inserted from above into the gap between the coils between the first U-phase coil 13Ua and the first V-phase coil 13Va, for example, after the lead wire 9a and the first U-phase coil 13Ua are connected.

[0073] At least a portion of the connection section CU2 is located between the second U-phase coil 13Ub and the second V-phase coil 13Vb. The intermediate section between the coils located between the second U-phase coil 13Ub and the second V-phase coil 13Vb includes at least a portion of the connection section CU2. The connection section CU2 is inserted from above into the gap between the coils between the second U-phase coil 13Ub and the second V-phase coil 13Vb, for example, after the first U-phase coil 13Ua and the second U-phase coil 13Ub are connected.

[0074] At least a portion of the connection section CV1 is located between the first V-phase coil 13Va and the first W-phase coil 13Wa. The intermediate section between the coils located between the first V-phase coil 13Va and the first W-phase coil 13Wa includes at least a portion of the connection section CV1. The connection section CV1 is inserted from above into the gap between the coils between the first V-phase coil 13Va and the first W-phase coil 13Wa, for example, after the lead wire 9b and the first V-phase coil 13Va have been connected.

[0075] At least a portion of the connection section CV2 is located between the second V-phase coil 13Vb and the second W-phase coil 13Wb. The intermediate portion between the coils located between the second V-phase coil 13Vb and the second W-phase coil 13Wb includes at least a portion of the connection section CV2. The connection section CV2 is inserted from above into the gap between the coils between the second V-phase coil 13Vb and the first W-phase coil 13Wa, for example, after the first V-phase coil 13Va and the second V-phase coil 13Vb have been connected.

[0076] At least a portion of the connection section CW1 is located between the first W-phase coil 13Wa and the second U-phase coil 13Ub. The intermediate section between the coils located between the first W-phase coil 13Wa and the second U-phase coil 13Ub includes at least a portion of the connection section CW1. The connection section CW1 is inserted from above into the gap between the coils between the first W-phase coil 13Wa and the second U-phase coil 13Ub, for example, after the lead wire 9c and the first W-phase coil 13Wa have been connected.

[0077] At least a portion of the connection section CW2 and at least a portion of the connection section CC are located between the second W-phase coil 13Wb and the first U-phase coil 13Ua. The intermediate section between the coils located between the second W-phase coil 13Wb and the first U-phase coil 13Ua includes at least a portion of the connection section CW2 and at least a portion of the connection section CC. The connection section CW2 is inserted from above into the gap between the coils between the second W-phase coil 13Wb and the first U-phase coil 13Ua, for example, after the first W-phase coil 13Wa and the second W-phase coil 13Wb have been connected. On the other hand, the connection section CC is inserted from below into the gap between the coils between the second W-phase coil 13Wb and the first U-phase coil 13Ua, for example, after the second U-phase coil 13Ub, the second V-phase coil 13Vb, and the second W-phase coil 13Wb have been connected.

[0078] As shown in Figure 6, an insulating tube 32a is placed over the jumper wires in the first U-phase coil 13Ua to the connection section CU2. The insulating tube 31 of the connection section CU2 is placed over the end of the insulating tube 32a on the connection section CU2 side. The end of the insulating tube 32a on the connection section CU2 side is located between the second U-phase coil 13Ub and the second V-phase coil 13Vb. The intermediate section between the coils located between the second U-phase coil 13Ub and the second V-phase coil 13Vb includes at least a part of the connection section CU2 and the end of the insulating tube 32a on the connection section CU2 side.

[0079] An insulating tube 32b is placed over the jumper wires in the first V-phase coil 13Va to the connection section CV2. The insulating tube 31 of the connection section CV2 is placed over the end of the insulating tube 32b on the connection section CV2 side. The end of the insulating tube 32b on the connection section CV2 side is located between the second V-phase coil 13Vb and the second W-phase coil 13Wb. The intermediate section between the coils located between the second V-phase coil 13Vb and the second W-phase coil 13Wb includes at least a part of the connection section CV2 and the end of the insulating tube 32b on the connection section CV2 side.

[0080] An insulating tube 32c is placed over the jumper wires in the first W-phase coil 13Wa to the connection section CW2. The insulating tube 31 of the connection section CW2 is placed over the end of the insulating tube 32c on the connection section CW2 side. The end of the insulating tube 32c on the connection section CW2 side is located between the second W-phase coil 13Wb and the first U-phase coil 13Ua. The intermediate section between the coils located between the second W-phase coil 13Wb and the first U-phase coil 13Ua includes at least a part of the connection section CW2 and the end of the insulating tube 32c on the connection section CW2 side.

[0081] In the examples of Figures 6 and 7, one connection is located in the inter-coil gap other than the gap between the second W-phase coil 13Wb and the first U-phase coil 13Ua, but multiple connection parts may be located there. Also, one connection part may be located in the inter-coil gap between the second W-phase coil 13Wb and the first U-phase coil 13Ua, or three or more connection parts may be located there. Furthermore, at least one of the N inter-coil gaps may be an inter-coil gap in which no connection part is located. Also, at least one of the connection parts CU1, CU2, CV1, CV2, CW1, CW2, and CC may not be located in an inter-coil gap.

[0082] The intermediate portion between the coils may include at least a part of the insulating sheet 23, as shown in the examples in Figures 6 and 7. The connection portion may also be sandwiched between the coil 13 and the insulating sheet 23 in the gap between the coils. This makes it less likely for floating wires to occur. In other words, the spacing between wires in one wound coil tends to be narrower. Here, the insulating sheet 23 inserted into the slot 120 between the teeth 121 around which the first U-phase coil 13Ua is wound and the teeth 121 around which the first V-phase coil 13Va is wound is called the specific insulating sheet 23. For example, the connection portion CU1 may be sandwiched between the first U-phase coil 13Ua and the portion of the specific insulating sheet 23 located in the gap between the coils. Alternatively, the connection portion CU1 may be sandwiched between the first V-phase coil 13Va and the portion of the specific insulating sheet 23 located in the gap between the first U-phase coil 13Ua and the first V-phase coil 13Va. The same applies to connection portions other than the connection portion CU1.

[0083] The connection of the N coils 13 may be other than a series Y connection. Figure 16 is a schematic diagram showing an example of how the N coils 13 are connected in a parallel Y connection. Figure 17 is a schematic diagram showing an example of how the N coils 13 are connected in a series Δ connection. Figure 18 is a schematic diagram showing an example of how the N coils 13 are connected in a parallel Δ connection.

[0084] In the parallel Y-connection shown in Figure 16, the first U-phase coil 13Ua and the second U-phase coil 13Ub are connected in parallel. Also, the first V-phase coil 13Va and the second V-phase coil 13Vb are connected in parallel. Furthermore, the first W-phase coil 13Wa and the second W-phase coil 13Wb are connected in parallel. In the example of Figure 16, the stator 11 has a connection section CU11 to which a lead wire 9a is connected to one end of the first U-phase coil 13Ua and one end of the second U-phase coil 13Ub. The stator 11 has a connection section CV11 to which a lead wire 9b is connected to one end of the first V-phase coil 13Va and one end of the second V-phase coil 13Vb. The stator 11 has a connection section CW11 to which a lead wire 9c is connected to one end of the first W-phase coil 13Wa and one end of the second W-phase coil 13Wb. The stator 11 has a connection section CC11 to which the other end of the first U-phase coil 13Ua, the other end of the second U-phase coil 13Ub, the other end of the first V-phase coil 13Va, the other end of the second V-phase coil 13Vb, the other end of the first W-phase coil 13Wa, and the other end of the second W-phase coil 13Wb are connected. The connection point between the other end of the first U-phase coil 13Ua, the other end of the second U-phase coil 13Ub, the other end of the first V-phase coil 13Va, the other end of the second V-phase coil 13Vb, the other end of the first W-phase coil 13Wa, and the other end of the second W-phase coil 13Wb is also called the neutral point.

[0085] In the example shown in Figure 16, the four connection points CU11, CV11, CW11, and CC11 may be located in, for example, four of the six gaps between coils. At least two of the four connection points CU11, CV11, CW11, and CC11 may be located in a single gap between coils. Furthermore, at least one of the four connection points CU11, CV11, CW11, and CC11 does not need to be located in a gap between coils.

[0086] In the series delta connection shown in Figure 17, the first U-phase coil 13Ua and the second U-phase coil 13Ub are connected in series. Also, the first V-phase coil 13Va and the second V-phase coil 13Vb are connected in series. Also, the first W-phase coil 13Wa and the second W-phase coil 13Wb are connected in series. In the example in Figure 17, the stator 11 has a connection section CU21 where one end of the first U-phase coil 13Ua is connected to one end of the second U-phase coil 13Ub. The stator 11 has a connection section CV21 where one end of the first V-phase coil 13Va is connected to one end of the second V-phase coil 13Vb. The stator 11 has a connection section CW21 where one end of the first W-phase coil 13Wa is connected to one end of the second W-phase coil 13Wb. The stator 11 has a connection section CUW1 in which lead wire 9a is connected to the other end of the first U-phase coil 13Ua and the other end of the second W-phase coil 13Wb. The stator 11 has a connection section CUV1 in which lead wire 9b is connected to the other end of the second U-phase coil 13Ub and the other end of the first V-phase coil 13Va. The stator 11 has a connection section CVW1 in which lead wire 9c is connected to the other end of the second V-phase coil 13Vb and the other end of the first W-phase coil 13Wa.

[0087] In the example shown in Figure 17, the six connection points CU21, CV21, CW21, CUW1, CUV1, and CVW1 may be located, for example, in the gaps between the six coils. At least two of the six connection points CU21, CV21, CW21, CUW1, CUV1, and CVW1 may be located in one of the gaps between the coils. Also, at least one of the six connection points CU21, CV21, CW21, CUW1, CUV1, and CVW1 does not have to be located in the gaps between the coils.

[0088] In the parallel delta connection shown in Figure 18, the first U-phase coil 13Ua and the second U-phase coil 13Ub are connected in parallel. Also, the first V-phase coil 13Va and the second V-phase coil 13Vb are connected in parallel. Furthermore, the first W-phase coil 13Wa and the second W-phase coil 13Wb are connected in parallel. In the example of Figure 18, the stator 11 has a connection section CUW2 to which lead wires 9a are connected to one end of the first U-phase coil 13Ua, one end of the second U-phase coil 13Ub, one end of the first W-phase coil 13Wa, and one end of the second W-phase coil 13Wb. The stator 11 has a connection section CUV2 in which lead wire 9b is connected to the other end of the first U-phase coil 13Ua, the other end of the second U-phase coil 13Ub, one end of the first V-phase coil 13Va, and one end of the second V-phase coil 13Vb. The stator 11 also has a connection section CVW2 in which lead wire 9c is connected to the other end of the first V-phase coil 13Va, the other end of the second V-phase coil 13Vb, the other end of the first W-phase coil 13Wa, and the other end of the second W-phase coil 13Wb.

[0089] In the example shown in Figure 18, the three connection points CUW2, CUV2, and CVW2 may be located in, for example, three of the six gaps between coils. At least two of the three connection points CUW2, CUV2, and CVW2 may be located in a single gap between coils. Furthermore, at least one of the three connection points CUW2, CUV2, and CVW2 does not need to be located in a gap between coils.

[0090] <Example of method for arranging the heat conductive member on the coil> The heat conductive member 6 is provided on the coil 13 by, for example, being applied to the coil 13. The heat conductive member 6 is applied to the coil 13 by, for example, a high-pressure injection machine. The high-pressure injection machine is equipped with a nozzle 900 that discharges the heat conductive member 6. The heat conductive member 6 is applied to each coil 13 by the nozzle 900 after, for example, the substrate 5 is attached to the stator 11. The heat conductive member 6 is applied to at least the upper coil end 131 and the lower coil end 132 of each coil 13. The heat conductive member 6 may also be provided on the coil 13 by hand.

[0091] Figure 19 is a schematic diagram showing an example of a method for applying the heat conductive member 6 to the lower coil end 132. As shown in Figure 19, the nozzle 900 of the high-pressure injector is positioned below the lower coil end 132. The nozzle 900 then applies the heat conductive member 6 to the lower coil end 132 from a direction along the axial direction. Applying the heat conductive member 6 to the lower coil end 132 from a direction along the axial direction makes it easier for the heat conductive member 6 to be properly applied to the lower coil end 132.

[0092] The nozzle 900 moves along the circumferential direction, applying the heat conductive member 6 to each of the N lower coil ends 132 arranged in the circumferential direction from a direction along the axial direction. For example, after the heat conductive member 6 has been applied to one lower coil end 132, the heat conductive member 6 extending from the nozzle 900 is detached from the nozzle 900 by a predetermined member. The nozzle 900 then moves to the underside of the lower coil end 132 adjacent to the lower coil end 132 to which the heat conductive member 6 has been applied, and applies the heat conductive member 6 to that adjacent lower coil end 132, as shown in Figure 20. The heat conductive member 6 extending from the nozzle 900 is then detached from the nozzle 900 by a predetermined member. Thereafter, the heat conductive member 6 is applied to the remaining lower coil ends 132 in the same manner by the nozzle 900. Figure 21 is a schematic diagram showing an example of how the heat conductive member 6 has been applied to each lower coil end 132.

[0093] Furthermore, the heat conductive member 6 may not be applied to some of the N lower coil ends 132. Also, when the heat conductive member 6 is applied to the lower coil ends 132 of the coil 13, it may also be applied to at least one of the pair of coil sides 133 of the coil 13. In addition, the heat conductive member 6 may be applied to two coils 13 such that it is located in the region between the two coils 13 wound around two adjacent teeth 121 in the circumferential direction.

[0094] Figures 22-24 are schematic diagrams showing an example of a method for applying the heat conductive member 6 to the upper coil ends 131. The nozzle 900 applies the heat conductive member 6 to the upper coil ends 131 through the gap between the motor 3 and the substrate 5. Specifically, as shown in Figure 22, the nozzle 900 applies the heat conductive member 6 to the upper coil ends 131 through the gap between the stator 11 of the motor 3 and the substrate 5. The nozzle 900 moves along the circumferential direction and applies the heat conductive member 6 to each of the N upper coil ends 131 arranged in the circumferential direction from the direction of the winding axis.

[0095] After the heat conductive material 6 is applied to the upper coil end 131, for example, the heat conductive material 6 extending from the nozzle 900 is separated from the nozzle 900 at the outer edge of the substrate 5. This allows the substrate 5 of the motor device 1 to be effectively used for separating the heat conductive material 6 from the nozzle 900.

[0096] For example, the nozzle 900 applies the heat conductive member 6 to one upper coil end 131 from the direction of the winding axis of the upper coil end 131, and then moves axially away from the stator 11. As the nozzle 900 moves axially away from the stator 11, the heat conductive member 6 extending from the nozzle 900 comes into contact with the outer edge of the substrate 5, as shown in Figure 23. Then, as the nozzle 900 moves further axially away from the stator 11 and reaches the outside of the substrate 5, the heat conductive member 6 extending from the nozzle 900 is separated from the nozzle 900 at the outer edge of the substrate 5, as shown in Figure 24. When the heat conductive member 6 extending from the nozzle 900 is separated from the nozzle 900 at the outer edge of the substrate 5, the nozzle 900 moves as close as possible to the outer edge of the substrate 5, making it easier for the heat conductive member 6 extending from the nozzle 900 to be separated from the nozzle 900 at the outer edge of the substrate 5.

[0097] After the heat conductive member 6 extending from the nozzle 900 is detached from the nozzle 900 at the outer edge of the substrate 5, the nozzle 900 moves circumferentially to the upper coil end 131 adjacent to the upper coil end 131 to which the heat conductive member 6 has been applied. The nozzle 900 then applies the heat conductive member 6 to the adjacent upper coil end 131 through the gap between the stator 11 and the substrate 5. Subsequently, the heat conductive member 6 extending from the nozzle 900 is detached from the nozzle 900 at the outer edge of the substrate 5. Thereafter, the heat conductive member 6 is applied to the remaining upper coil ends 131 by the nozzle 900 in the same manner.

[0098] Furthermore, when the heat conductive member 6 is applied to the upper coil end 131 of the coil 13, it may also be applied to at least one of the pair of coil sides 133 of the coil 13. In addition, the heat conductive member 6 may not be applied to some of the N upper coil ends 131.

[0099] After the heat conductive material 6 is applied to each lower coil end 132 and each upper coil end 131 as described above, the motor 3, including the stator 11 to which the substrate 5 is attached, is inserted into the first case 2a. Subsequently, the second case 2b and the third case 2c are attached to the first case 2a. As shown in Figure 4 above, the heat conductive material 6 applied to the lower coil end 132 comes into contact with, for example, the third case 2c. The heat conductive material 6 applied to the upper coil end 131 comes into contact with, for example, the first case 2a or the second case 2b.

[0100] As described above, in this example, the motor device 1 is equipped with an inter-coil intermediate section located between the coils. Therefore, when a heat conductive member 6 is provided between the coil 13 and the case 2 to reduce the amount of heat generated by the coil 13, the inter-coil intermediate section located between the coil 13 and the adjacent coil 13 makes it difficult for the heat conductive member 6 to enter between the coil 13 and the adjacent coil 13. Thus, the amount of heat conductive member 6 used in the motor device 1 can be reduced. As a result, the cost of the motor device 1 can be reduced.

[0101] Furthermore, as in this example, if the intermediate portion between coils includes at least a part of a connection section where at least one coil 13 is connected to another wire (for example, another coil 13 or lead wire 9), the connection section can be effectively utilized as at least a part of the intermediate portion between coils.

[0102] Furthermore, the positioning of the heat conductive member 6 between the upper coil end 131 and the lower coil end 132 of the coil 13 and the case 2 makes it less likely for the coil 13 to generate heat.

[0103] The upper inner wall portion 212 of the upper insulating member 21, which is located on the inner diameter side of the upper coil end 131, may have a portion that protrudes above the upper coil end 131, as shown in Figures 8, 22, 23, and 24. In this case, when a heat conductive member 6 is provided on the upper coil end 131, the heat conductive member 6 is less likely to protrude on the inner diameter side of the upper coil end 131. Therefore, the amount of heat conductive member 6 used in the motor device 1 can be reduced. As a result, the cost of the motor device 1 can be reduced. Note that at least one of the N upper inner wall portions 212 does not need to have a portion that protrudes above the upper coil end 131.

[0104] In the example shown in Figure 8, the upper outer wall portion 213 located on the outer diameter side of the upper coil end 131 does not have a portion that protrudes above the upper coil end 131. However, as shown in Figure 25, it may have such a protruding portion. In this case, when a heat conductive member 6 is provided on the upper coil end 131, the heat conductive member 6 is less likely to protrude on the outer diameter side of the upper coil end 131. Therefore, the amount of heat conductive member 6 used in the motor device 1 can be reduced. At least one of the N upper outer wall portions 213 may have a portion that protrudes above the upper coil end 131.

[0105] Furthermore, in the example shown in Figure 8, the lower inner wall portion 222 located on the inner diameter side of the lower coil end 132 does not have a portion that protrudes below the lower coil end 132, but it may have such a protruding portion. At least one of the N lower inner wall portions 222 may have a portion that protrudes below the lower coil end 132.

[0106] Furthermore, in the example shown in Figure 8, the lower outer wall portion 223 located on the outer diameter side of the lower coil end 132 does not have a portion that protrudes below the lower coil end 132, but it may have such a portion. At least one of the N lower outer wall portions 223 may have a portion that protrudes below the lower coil end 132.

[0107] The outer shape 50 of the substrate 5 used to separate the heat conductive member 6 from the nozzle 900 may be a circle with a uniform diameter, as shown in Figure 26. In this case, when separating the heat conductive member 6 from the nozzle 900 using the outer edge of the substrate 5 each time the heat conductive member 6 is applied to one upper coil end 131, it becomes easier to separate the heat conductive member 6 from the nozzle 900 compared to the case where the diameter of the outer shape 50 of the substrate 5 is uneven, as shown in Figure 5, etc.

[0108] In the example above, the heat conductive member 6 was detached from the nozzle 900 each time it was applied to one coil end, but the method of applying the heat conductive member 6 to each coil end is not limited to this. For example, the heat conductive member 6 may be applied to each upper coil end 131 or each lower coil end 132 while the nozzle 900 moves in the circumferential direction without the heat conductive member 6 being detached from the nozzle 900, and then the heat conductive member 6 may be detached from the nozzle 900. Also, similar to the method of applying the heat conductive member 6 to the upper coil end 131, the heat conductive member 6 may be applied to the lower coil end 132 from the direction of the winding axis of the lower coil end 132. Furthermore, in the method of applying the heat conductive member 6 to the upper coil end 131, the heat conductive member 6 is detached from the nozzle 900 each time the heat conductive member 6 is applied to the upper coil end 131, whereas in the method of applying the heat conductive member 6 to the lower coil end 132, the heat conductive member 6 is applied to the lower coil end 132 while the nozzle 900 moves in the circumferential direction without being detached from the nozzle 900, and then the heat conductive member 6 may be detached from the nozzle 900.

[0109] As shown in Figure 16 above, when the connection of the multiple coils 13 is a parallel Y connection, the stator 11 includes a connection section CC11 with eight wires connected. Also, as shown in Figure 18 above, when the connection of the multiple coils 13 is a parallel Δ connection, the stator 11 includes connection sections CUW2, CUV2, and CVW2 with five wires connected. Connection sections with a large number of wires connected, such as CC11, CUW2, CUV2, and CVW2, may be difficult to place in the gaps between coils. Conversely, it may be necessary to increase the gaps between coils so that connection sections with a large number of wires can fit in the gaps between coils, which may increase the size of the stator 11.

[0110] In contrast, when the connections of the multiple coils 13 are in a series Y connection (see Figure 15) or a series delta connection (see Figure 17), the number of wires connected at the connection point is a maximum of three. Therefore, it becomes easier to place the connection point in the gap between the coils. Alternatively, even when the connection point is placed in the gap between the coils, it is not necessary to increase the gap between the coils, and the size of the stator 11 can be reduced.

[0111] The configuration of the motor device 1 is not limited to the above example. For example, the core 12 of the stator 11 may be a split stator core. Figures 27 to 29 are schematic diagrams showing an example of a stator 11 (also called stator 11A) equipped with a core 12 (also called a split core 12A) which is a split stator core. A motor 3 equipped with a split core 12A is also called a split core motor or split core motor. Figures 27 and 28 show the stator 11A together with a circuit board 5 attached to the stator 11A. Figure 29 shows the stator 11A as viewed from above. In Figures 27 to 29, as in Figures 8 to 10, the multiple lead wires 9, the multiple lead wires 5a, the connections between the coils 13, the connections between the coils 13 and the lead wires 9, and the jumper wires of the coils 13 are not shown. In this example, the split core 12A does not necessarily have to be located between the coils 13. For example, it may be located axially outward from the coil end, or it may be located axially between the substrate 5 and the upper coil end 131.

[0112] The divided core 12A is composed of N core segments 129 combined together. Each core segment 129 has one tooth 121. The N core segments 129 are arranged in a ring shape. N coils 13 are wound around the teeth 121 of each of the N core segments 129. For example, each core segment 129 is connected to the adjacent core segments 129 by welding or the like. Figure 30 is a schematic diagram showing an example of the structure shown in Figure 29 with the N coils 13 removed.

[0113] In the stator 11A, the upper insulating member 21 is composed of N insulating members 219, and the N insulating members 219 are each attached to the upper side of the N core segments 129. Each insulating member 219 has an upper insulating portion 211 that insulates the teeth 121 from the upper coil end 131 of the coil 13 wound around the teeth 121, an upper inner wall portion 212 located on the inner diameter side of the upper coil end 131, and an upper outer wall portion 213 located on the outer diameter side of the upper coil end 131.

[0114] As shown in Figure 28, the upper outer wall portion 213 has a notch portion 213a. The notch portion 213a is recessed from the upper end to the lower end of the upper outer wall portion 213. When viewing the coil 13 from the outside of the stator 11A along the winding axis direction of the coil 13, as shown in Figure 28, the upper coil end 131 of the coil 13 is partially exposed from the notch portion 213a. Note that the upper outer wall portion 213 does not necessarily have to have a notch portion 213a.

[0115] Furthermore, the insulating member 219 is connected to the upper outer wall portion 213 and has a first columnar portion 214 and a second columnar portion 215 that protrude above the upper outer wall portion 213. The first columnar portion 214 is inserted into a through hole in the substrate 5.

[0116] In the stator 11A, the lower insulating member 22 is composed of N insulating members 229. The N insulating members 229 are each attached to the underside of the N core segments 129. Each insulating member 229 has a lower insulating portion 221 that insulates between the teeth 121 and the lower coil end 132 of the coil 13 wound around the teeth 121, a lower inner wall portion 222 located on the inner diameter side of the lower coil end 132, and a lower outer wall portion 223 located on the outer diameter side of the lower coil end 132. As shown in Figure 28, the lower outer wall portion 223 has a notch 223a. The notch 223a is recessed from the lower end to the upper end of the lower outer wall portion 223. When viewing the coil 13 from the outside of the stator 11A along the winding axis direction of the coil 13, as shown in Figure 28, the lower coil end 132 of the coil 13 is partially exposed from the notch 223a. Furthermore, the lower outer wall portion 223 does not necessarily need to have a notch 223a.

[0117] The stator 11A is equipped with 2N insulating sheets 23. As shown in Figure 30, two insulating sheets 23 are placed in each slot 120. The two insulating sheets 23 in a slot 120 are arranged in the circumferential direction. Hereafter, of the two insulating sheets 23 placed in a target slot 120, the insulating sheet 23 on the target first tooth 121 side will be called the target first insulating sheet 23. Of the two insulating sheets 23 placed in a target slot 120, the insulating sheet 23 on the target second tooth 121 side will be called the target second insulating sheet 23.

[0118] The first insulating sheet 23 insulates the first coil side 133 of the first coil 13 wound around the first tooth 121 from the first tooth 121. The second insulating sheet 23 insulates the second coil side 133 of the second coil 13 wound around the second tooth 121 from the second tooth 121. The pair of coil sides 133 of the coil 13 wound around the tooth 121 are insulated from the tooth 121 by the two insulating sheets 23. The first insulating sheet 23 surrounds the first coil side 133, for example, around its longitudinal direction. The second insulating sheet 23 surrounds the second coil side 133, for example, around its longitudinal direction.

[0119] In the stator 11A having a divided core 12A, the distance between the target first coil side 133 and the target second coil side 133 located in the target slot 120 is smaller compared to the stator 11 shown in Figures 6 and 7 above. In other words, in the stator 11A, the distance between two adjacent coils 13 in the circumferential direction is smaller compared to the stator 11 shown in Figures 6 and 7 above.

[0120] Between the target first coil side 133 and the target second coil side 133, a portion of the target first insulating sheet 23 and a portion of the target second insulating sheet 23 are located. The portion of the target first insulating sheet 23 and the portion of the target second insulating sheet 23 are, for example, sandwiched between the target first coil side 133 and the target second coil side 133.

[0121] A portion of the first insulating sheet 23 and a portion of the second insulating sheet 23 located between the target first coil side 133 and the target second coil side 133 can be said to be an insulating portion that insulates the target first coil side 133 and the target second coil side 133. In other words, a portion of the first insulating sheet 23 and a portion of the second insulating sheet 23 located between the target first coil side 133 and the target second coil side 133 can be said to be an insulating portion that insulates the coil 13 having the target first coil side 133 and the coil 13 having the target second coil side 133. In this example, the intermediate portion between the coils located between the coil 13 having the target first coil side 133 and the coil 13 having the target second coil side 133 includes a portion of the first insulating sheet 23 and a portion of the second insulating sheet 23. The intermediate portion between two coils 13 adjacent to each other in the circumferential direction includes an insulating portion that insulates the two coils 13.

[0122] In the stator 11A, one stator segment 19 is composed of one core segment 129, one coil 13 wound around the teeth 121 of the core segment 129, two insulating sheets 23 that insulate a pair of coil sides 133 of the coil 13 from the teeth 121, one insulating member 219 attached to the core segment 129, and one insulating member 229 attached to the core segment 129. The stator 11A is composed of N stator segments 19 combined together. The N stator segments 19 are arranged in a ring shape. After the N stator segments 19 are manufactured, the stator 11A is manufactured by combining the manufactured N stator segments 19.

[0123] As described above, in the stator 11A having a divided core 12A, the distance between two adjacent coils 13 in the circumferential direction is small. Therefore, when a heat conductive member 6 is provided between the coil 13 and the case 2, it becomes difficult for the heat conductive member 6 to fit between the coil 13 and the adjacent coil 13. Thus, the amount of heat conductive member 6 used in the motor device 1 can be reduced.

[0124] Furthermore, in this example, a notch 213a is provided in the upper outer wall portion 213 of the upper insulating member 21 on the substrate 5 side. As a result, as shown in Figure 31, the heat conductive member 6 can be applied to the upper coil end 131 through the notch 213a. Therefore, it becomes easier to apply the heat conductive member 6 to the upper coil end 131.

[0125] Furthermore, a notch 213a may be provided in the upper outer wall portion 213 of the stator 11 as shown in Figures 4 to 10, etc. Also, if the voltage applied to the coil 13 of the stator 11A is low, the stator 11A may not be provided with an insulating sheet 23.

[0126] <Examples of Motor Device Usage> The motor device 1 can be used in various electrical devices. For example, the motor device 1 may be used in power tools or other electrical devices. Figure 32 is a schematic diagram showing an example of a power tool 500 equipped with the motor device 1.

[0127] The power tool 500 is, for example, a random orbital sander. The power tool 500 includes a case 501. The case 501 houses a motor unit 1, a plurality of lead wires 9 and a plurality of lead wires 5a, etc. The power tool 500 also includes a drive unit driven by the motor unit 1. The drive unit may include a fan 502. The fan 502 is housed in the case 501. Furthermore, if the power tool 500 is a random orbital sander, the drive unit may include, for example, an eccentric pulley for causing an eccentric movement of the pad to which the sanding paper is attached.

[0128] The case 501 is provided with multiple intake ports 501a for drawing air into the case 501 from the outside. The case 501 is also provided with multiple exhaust ports 501b for discharging air from inside the case 501 to the outside. The air drawn into the case 501 through the multiple intake ports 501a flows through the case 501 and is discharged to the outside through the multiple exhaust ports 501b. The airflow within the case 501 cools the inside of the case 501.

[0129] The motor unit 1 is located within the airflow path inside the case 501. The rotation of the fan 502 draws air into the case 501 from multiple intake ports 501a, and the drawn-in air flows towards the motor unit 1. The air drawn into the case 501 then hits the case 2 of the motor unit 1 due to the rotation of the fan 502, and is then discharged outside the case 501 from multiple exhaust ports 501b.

[0130] In this example, as described above, the space inside the case 2 of the motor device 1 is sealed. Therefore, even when the power tool 500 is used for metalworking or the like, dust from iron and other materials is unlikely to enter the case 2. Thus, the possibility of dust adhering to the motor 3 and causing malfunctions in the motor 3 is reduced.

[0131] If the space inside the case 2 of the motor device 1 is sealed, the air taken into the case 501 of the power tool 500 cannot be directed onto the coil 13 inside the case 2 of the motor device 1. In other words, the coil 13 of the motor device 1 cannot be cooled by the air flowing inside the case 501 of the power tool 500. Even in such a case, in this example, the heat generated in the coil 13 can be released to the outside of the motor device 1 through the heat conductive member 6 and the case 2, so the coil 13 is less likely to overheat.

[0132] The power tool 500 equipped with the motor device 1 may be something other than a random orbital sander. For example, the power tool 500 may be a disc grinder, an impact driver, a drill driver, a circular saw, a reciprocating saw, or any other type of power tool. For example, if the power tool 500 is a disc grinder, the drive unit of the power tool 500 may include gears and a rotating grinding wheel driven by the motor device 1.

[0133] Figure 33 is a schematic diagram showing an example of a power supply unit 600 capable of supplying power voltage to an electric power tool 500. For example, multiple electric power tools 500 can be connected to the power supply unit 600 simultaneously. The electric power tools 500 connected to the power supply unit 600 can operate based on the power voltage supplied from the power supply unit 600. In other words, the electric power tools 500 can operate based on the power supplied from the power supply unit 600. The power voltage of the electric power tool 500 can also be said to be, for example, the power voltage of the motor 3 of the motor unit 1 of the electric power tool 500.

[0134] Hereafter, when we simply refer to "motor device 1," we mean the motor device 1 provided by the power tool 500. Similarly, when we simply refer to "motor 3," we mean the motor 3 included in the motor device 1 provided by the power tool 500.

[0135] Multiple types of power tools 500 can be connected to the power supply unit 600 simultaneously, or multiple power tools 500 of the same type can be connected simultaneously. Figure 33 shows an example of one power tool 500 connected to the power supply unit 600. The power tool 500 shown in Figure 33 is a disc grinder.

[0136] The power supply unit 600 includes, for example, M connectors 602 (where M is an integer of 2 or more). Each of the M connectors 602 can be connected to a power tool 500. The power supply unit 600 can simultaneously connect up to M power tools 500. In the example in Figure 33, M=4, but M=2, M=3, or M>4.

[0137] The power tool 500 is connected to the power supply unit 600, for example, by a connecting cable 700. One end of the connecting cable 700 is detachable from the power supply unit 600, and the other end of the connecting cable 700 is detachable from the power tool 500. The multiple lead wires 9 and multiple lead wires 5a of the power tool 500 are electrically connected to the power supply unit 600 through the connecting cable 700.

[0138] Connectors 701 and 702 are provided at one end and the other end of the connecting cable 700, respectively. Connector 702 is connected to connector 510 on the power tool 500, and connector 701 is connected to connector 602 on the power supply unit 600. One end of the connecting cable 700 may be fixed to the power supply unit 600 and not detachable from the power supply unit 600. The other end of the connecting cable 700 may be fixed to the power tool 500 and not detachable from the power tool 500.

[0139] The power supply unit 600 generates the power supply voltage for the power tool 500 based on, for example, an AC voltage. The AC voltage is supplied to the power supply unit 600 through a connecting cable 750. One end of the connecting cable 750 is detachable from the power supply unit 600. A connector 751 is provided at the other end of the connecting cable 750. The power supply unit 600 is provided with a connector 603 that connects to the connector 751. Alternatively, one end of the connecting cable 750 may be fixed to the power supply unit 600 and not detachable from it.

[0140] The other end of the connecting cable 750 is provided with a connector 752 that connects to an outlet that supplies AC voltage from a commercial power source or the like. The power supply unit 600 is supplied with single-phase AC voltage from a commercial power source or the like through the connecting cable 750. For example, the power supply unit 600 is supplied with AC voltage with an effective value of 100V.

[0141] The power supply unit 600 generates a DC voltage of, for example, 140V based on an AC voltage with an effective value of 100V supplied through the connecting cable 750. The power supply unit 600 may also convert the AC voltage with an effective value of 100V to a DC voltage of 140V using, for example, a full-wave rectifier circuit and a smoothing capacitor.

[0142] The power supply unit 600 includes an inverter circuit that controls the motor 3 of the motor unit 1, and a control circuit that controls the inverter circuit. The inverter circuit generates a drive voltage for controlling the motor 3 based on a 140V DC voltage, controlled by the control circuit. The drive voltage for controlling the motor 3 can be said to be the power supply voltage for the motor 3, or the power supply voltage for the motor unit 1. The power supply unit 600 also generates and outputs the power supply voltage (also called the sensor power supply voltage) for the sensor mounted on the circuit board 5 of the motor unit 1.

[0143] The sensor signal output by the sensor mounted on the circuit board 5 of the motor device 1 is input to the control circuit of the power supply unit 600 through the connecting cable 700 and a portion of the multiple lead wires 5a of the power tool 500. The control circuit controls the inverter circuit based on the sensor signal from the motor device 1. The three-phase drive voltage output by the inverter circuit is supplied to the motor 3 through the connecting cable 700 and the multiple lead wires 9 of the power tool 500. The power supply voltage of the motor 3 output by the inverter circuit, that is, the three-phase drive voltage (specifically the maximum voltage) output by the inverter circuit, is, for example, 140V. The sensor power supply voltage output by the power supply unit 600 is supplied to the sensor mounted on the circuit board 5 through the connecting cable 700 and a portion of the multiple lead wires 5a of the power tool 500.

[0144] Hereafter, the power supply voltage of motor 3 will also be referred to as the motor voltage. Furthermore, the power tool 500 connected to the power supply unit 600 may be referred to as the connected power tool 500.

[0145] When P (P is an integer less than or equal to M) power tools 500 are connected to the power supply unit 600, the power supply unit 600 may output a motor voltage to only one of the P power tools 500, or it may output a motor voltage to each of Q (Q is an integer less than P) of the P power tools 500 individually. Alternatively, the power supply unit 600 may output a motor voltage to each of the P power tools 500 individually.

[0146] Furthermore, the power supply unit 600 may have only one connector 602. In other words, the power supply unit 600 may not be able to connect multiple power tools 500 simultaneously, and may only be able to connect one power tool 500 at a time.

[0147] Furthermore, the power supply unit 600 may be equipped with a battery. In this case, the power supply unit 600 may generate a motor voltage of, for example, 20V or more and 40V or less based on the DC voltage (also called the battery voltage) output from the battery.

[0148] Hereafter, a power supply unit 600 that generates motor voltage based on AC voltage will be referred to as an AC-type power supply unit 600. An AC-type power supply unit 600 can also be said to operate based on AC voltage. Furthermore, a power supply unit 600 that generates motor voltage based on battery voltage will be referred to as a battery-type power supply unit 600. A battery-type power supply unit 600 can also be said to operate based on battery voltage.

[0149] Furthermore, a power tool 500 in which the motor 3 operates based on the motor voltage (also called the first motor voltage) output by the AC power supply unit 600 is called the first power tool 500. Furthermore, a power tool 500 in which the motor 3 operates based on the motor voltage (also called the second motor voltage) output by the battery power supply unit 600 is called the second power tool 500. Furthermore, the motor 3 equipped in the first power tool 500 is called the first motor 3, and the motor 3 equipped in the second power tool 500 is called the second motor 3. The first motor 3 rotates based on the first motor voltage, and the second motor 3 rotates based on the second motor voltage.

[0150] The first motor voltage output by the AC power supply 600 is higher than, for example, the second motor voltage output by the battery power supply 600. As described above, for example, the first motor voltage is 140V, and the second motor voltage is 20V or more and 40V or less. When comparing the first motor voltage and the second motor voltage, it can be said that the first motor voltage is higher and the second motor voltage is lower.

[0151] Now, let's consider the case where the output power of the first motor 3 and the output power of the second motor 3 are the same. In this case, since the voltage of the first motor is higher than the voltage of the second motor, the current flowing through the first motor 3 (also called the first motor current) will be smaller than the current flowing through the second motor 3 (also called the second motor current). When comparing the first motor current and the second motor current, it can be said that the first motor current is smaller and the second motor current is larger.

[0152] For example, consider the case where the coil connection in the second motor 3 is a parallel Y connection (see Figure 16) or a parallel Δ connection (see Figure 18). Since the voltage of the second motor is low, the number of windings in each coil 13 of the second motor 3 can be reduced. On the other hand, although the current of the second motor is large, since the two coils 13 of the same phase (for example, the first U-phase coil 13Ua and the second U-phase coil 13Ub) are connected in parallel, the current flowing through each of the two coils 13 of the same phase can be reduced. Therefore, the wire diameter of each coil 13 of the second motor 3 can be reduced.

[0153] Thus, when the coil connection in the second motor 3 is a parallel Y connection or a parallel delta connection (in other words, when multiple coils 13 of the same phase are connected in parallel in the second motor 3), the wire diameter of the coil 13 of the second motor 3 can be reduced, and the number of windings of the coil 13 of the second motor 3 can be reduced. This makes it easier to wind the coil 13 of the second motor 3 onto the teeth 121. Therefore, when the coil connection in the second motor 3 is a parallel Y connection or a parallel delta connection, the assembly workability of the stator 11 is improved. When the power tool 500 operates based on the power supply voltage supplied from the battery-type power supply unit 600, the assembly workability of the second motor 3 is improved by making the coil connection in the second motor 3 of the power tool 500 a parallel Y connection or a parallel delta connection.

[0154] Furthermore, consider the case where the coil connection in the first motor 3 is a series Y connection (see Figure 15) or a series delta connection (see Figure 17). Since the current of the first motor is small, even if two coils 13 of the same phase are connected in series, the current flowing through each of the two coils 13 of the same phase can be reduced. Therefore, the current flowing through each coil 13 of the first motor 3 can be reduced. On the other hand, although the voltage of the first motor is high, since the two coils 13 of the same phase are connected in series, the voltage across each of the two coils 13 of the same phase can be reduced. Therefore, the number of windings in each coil 13 of the first motor 3 can be reduced.

[0155] Thus, when the coil connection in the first motor 3 is a series Y connection or a series delta connection (in other words, when multiple coils 13 of the same phase are connected in series in the first motor 3), the wire diameter of the coil 13 of the first motor 3 can be reduced, and the number of windings of the coil 13 of the first motor 3 can be reduced. This makes it easier to wind the coil 13 of the first motor 3 onto the teeth 121. Therefore, when the coil connection in the first motor 3 is a series Y connection or a series delta connection, the assembly workability of the stator 11 is improved. When the power tool 500 operates based on the power supply voltage supplied from the AC type power supply unit 600, the assembly workability of the first motor 3 is improved by making the coil connection in the first motor 3 of the power tool 500 a series Y connection or a series delta connection.

[0156] As described above, the motor device has been explained in detail, but the above explanation is illustrative in all respects, and this disclosure is not limited thereto. Furthermore, the various examples described above can be combined and applied insofar as they do not contradict each other. And it is understood that countless examples not illustrated can be conceived without falling outside the scope of this disclosure.

[0157] This disclosure includes the following:

[0158] In one embodiment, (1) the motor device comprises a case, a motor located inside the case and having a plurality of coils including a first coil and a second coil, an intermediate portion located between the first coil and the second coil, and a clay-like heat conductive member located between the first coil and the case.

[0159] (2) The motor device of (1) above, wherein the intermediate portion includes at least a part of a connection portion in which at least one coil of the plurality of coils is connected to a wire other than the at least one coil.

[0160] (3) The motor device according to (1) or (2) above, wherein the connections of the plurality of coils are in series delta connection or series Y connection.

[0161] (4) Any one of the motor devices described in (1) to (3) above, wherein the motor comprises a divided stator core and a plurality of coils wound around the divided stator core, and the intermediate portion includes an insulating portion that insulates the first coil and the second coil.

[0162] (5) Any one of the motor devices described in (1) to (4) above, wherein the first coil has a first coil end located at the end of the first coil in the direction of the rotation axis of the motor, and the heat conductive member is located between the first coil end and the case.

[0163] (6) The motor device according to (5) above, wherein the first coil further has a second coil end located on the opposite side from the first coil end, and the heat conductive member is located between the second coil end and the case.

[0164] (7) The motor device according to (5) or (6) above, wherein the motor has first teeth around which the first coil is wound, a first insulating portion that insulates the first teeth from the first coil end, and a first inner wall portion connected to the first insulating portion and located on the inner diameter side of the stator than the first coil end, wherein the first inner wall portion has a portion that protrudes from the first coil end along the rotation axis direction of the motor.

[0165] (8) Any one of the motor devices described in (5) to (7) above, wherein the motor has first teeth around which the first coil is wound, a first insulating portion that insulates the first teeth from the first coil end, and a first outer wall portion connected to the first insulating portion and located on the outer diameter side of the stator than the first coil end, wherein the first outer wall portion has a portion that protrudes from the first coil end along the rotation axis direction of the motor.

[0166] (9) Any one of the motor devices described in (5) to (8) above, wherein the motor has first teeth around which the first coil is wound, a first insulating portion that insulates the first teeth from the first coil end, and a first outer wall portion connected to the first insulating portion and located on the outer diameter side of the stator than the first coil end, the first outer wall portion having a notch.

[0167] (10) Any one of the motor devices described in (5) to (9) above, wherein each of the plurality of coils has a first coil end located at the end of the coil in the direction of the rotation axis, and a substrate is provided facing the first coil end of the plurality of coils in the direction of the rotation axis.

[0168] (11) The motor device according to (10) above, wherein the heat conductive member is located between the first coil end of the plurality of coils and the case, and the outer shape of the substrate is circular with a constant diameter.

[0169] (12) Any one of the motor devices described in (1) to (11) above, wherein the first coil has a first coil end located at the end of the first coil in the direction of the rotation axis of the motor, the motor has first teeth around which the first coil is wound, and an insulating portion that insulates the first teeth from the first coil end, the insulating portion having thermal conductivity.

[0170] (13) Any one of the motor devices described in (1) to (12) above, wherein the first coil has a first coil end located at the end of the first coil in the direction of the rotation axis of the motor, a second coil end located on the opposite side from the first coil end, and a first coil side connected to the first coil end and the second coil end, and the motor has a first tooth around which the first coil is wound, a first insulating portion that insulates the first tooth from the first coil end, a second insulating portion that insulates the first tooth from the second coil end, and a third insulating portion that insulates the first tooth from the first coil side, wherein the first insulating portion protrudes further toward the first coil side than the first tooth, and the second insulating portion does not protrude further toward the first coil side than the first tooth.

[0171] (14) Any one of the motor devices described in (1) to (13) above, wherein the first coil has a first coil side located on the side of the first coil in the direction of rotation of the motor, the motor has a first tooth around which the first coil is wound, and an insulating portion that insulates the first tooth from the first coil side, the insulating portion having thermal conductivity.

[0172] In one embodiment, the (15) power tool comprises one of the motor devices described in (1) to (14) above, and a drive unit driven by the motor device.

[0173] In one embodiment, the (16) coating method is a method for coating the heat conductive member provided in any one of the motor devices described in (5) to (8) above, wherein the heat conductive member is coated onto the first coil end from a direction along the rotation axis of the motor.

[0174] In one embodiment, (17) the coating method is a method for coating the heat conductive member provided in the motor device described in (9) above, wherein the heat conductive member is coated onto the first coil end through the notch.

[0175] In one embodiment, (18) coating method is a method for coating the heat conductive member provided in the motor device of (10) or (11) above, wherein the heat conductive member is applied to the first coil end from the gap between the motor and the substrate using a nozzle that discharges the heat conductive member, and after the heat conductive member is applied to the first coil end, the heat conductive member extending from the nozzle is separated from the nozzle at the outer edge of the substrate.

[0176] 1 Motor device 2 Case 3 Motor 5 Circuit board 6 Viscous heat conductive material 11 Stator 13 Coil 13Ua First U-phase coil 13Ub Second U-phase coil 13Va First V-phase coil 13Vb Second V-phase coil 13Wa First W-phase coil 13Wb Second W-phase coil 121 Teeth 131, 132 Coil end 133 Coil side 211, 221 Insulating part 212, 222 Inner wall part 213, 223 Outer wall part 213a Notch part 230 Insulating part 900 Nozzle CC, CC11, CU1, CU11, CU2, CUV1, CUV2, CUW1, CUW2, CV1, CV11, CV2, CVW1, CVW2, CW1, CW11, CW2 Connection section

Claims

1. A motor device comprising: a case; a motor located inside the case and having a plurality of coils including a first coil and a second coil; an intermediate portion located between the first coil and the second coil; and a clay-like heat conductive member located between the first coil and the case.

2. A motor device according to claim 1, wherein the intermediate portion includes at least a part of a connection portion in which at least one coil of the plurality of coils is connected to a wire other than the at least one coil.

3. A motor device according to claim 1 or claim 2, wherein the connections of the plurality of coils are in a series delta connection or a series Y connection.

4. A motor device according to any one of claims 1 to 3, wherein the motor comprises a divided stator core and a plurality of coils wound around the divided stator core, and the intermediate portion includes an insulating portion that insulates the first coil and the second coil.

5. A motor device according to any one of claims 1 to 4, wherein the first coil has a first coil end located at the end of the first coil in the direction of the rotation axis of the motor, and the heat conductive member is located between the first coil end and the case.

6. A motor device according to claim 5, wherein the first coil further has a second coil end located on the opposite side from the first coil end, and the heat conductive member is located between the second coil end and the case.

7. A motor device according to claim 5 or claim 6, wherein the motor has first teeth on which the first coil is wound, a first insulating portion that insulates the first teeth from the first coil end, and a first inner wall portion connected to the first insulating portion and located on the inner diameter side of the stator than the first coil end, wherein the first inner wall portion has a portion that protrudes from the first coil end along the rotation axis direction of the motor.

8. A motor device according to any one of claims 5 to 7, wherein the motor has first teeth on which the first coil is wound, a first insulating portion that insulates the first teeth from the first coil end, and a first outer wall portion connected to the first insulating portion and located on the outer diameter side of the stator than the first coil end, the first outer wall portion having a portion that protrudes from the first coil end along the rotation axis direction of the motor.

9. A motor device according to any one of claims 5 to 8, wherein the motor has first teeth on which the first coil is wound, a first insulating portion that insulates the first teeth from the first coil end, and a first outer wall portion connected to the first insulating portion and located on the outer diameter side of the stator than the first coil end, the first outer wall portion having a notch.

10. A motor device according to any one of claims 5 to 9, wherein each of the plurality of coils has a first coil end located at the end of the coil in the direction of the rotation axis, and the motor device comprises a substrate facing the first coil end of the plurality of coils in the direction of the rotation axis.

11. A motor device according to claim 10, wherein the heat conductive member is located between the first coil end of the plurality of coils and the case, and the outer shape of the substrate is a circle with a constant diameter.

12. A motor device according to any one of claims 1 to 11, wherein the first coil has a first coil end located at the end of the first coil in the direction of the rotation axis of the motor, the motor has first teeth around which the first coil is wound, and an insulating portion that insulates the first teeth from the first coil end, and the insulating portion is thermally conductive.

13. A motor device according to any one of claims 1 to 12, wherein the first coil has a first coil end located at the end of the first coil in the direction of the rotation axis of the motor, a second coil end located on the opposite side from the first coil end, and a first coil side connected to the first coil end and the second coil end, and the motor has a first tooth around which the first coil is wound, a first insulating portion that insulates the first tooth from the first coil end, a second insulating portion that insulates the first tooth from the second coil end, and a third insulating portion that insulates the first tooth from the first coil side, wherein the first insulating portion protrudes further toward the first coil side than the first tooth, and the second insulating portion does not protrude further toward the first coil side than the first tooth.

14. A motor device according to any one of claims 1 to 13, wherein the first coil has a first coil side located on the side of the first coil in the direction of rotation of the motor, the motor has a first tooth around which the first coil is wound, and an insulating portion that insulates the first tooth from the first coil side, and the insulating portion is thermally conductive.

15. A power tool comprising a motor device according to any one of claims 1 to 14, and a drive unit driven by the motor device.

16. A method for applying a heat conductive member to a motor device according to any one of claims 5 to 8, the method comprising applying the heat conductive member to the first coil end from a direction along the rotation axis of the motor.

17. A method for applying a heat conductive member to a motor device according to claim 9, comprising applying the heat conductive member to the first coil end through the notch.

18. A method for applying a heat conductive member to a motor device according to claim 10 or claim 11, comprising: applying the heat conductive member to the first coil end from the gap between the motor and the substrate using a nozzle that discharges the heat conductive member; and, after applying the heat conductive member to the first coil end, separating the heat conductive member extending from the nozzle at the outer edge of the substrate.

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