motor

Abstract

To provide a motor capable of cooling a coil end without flowing a coolant to a space where a motor part is not arranged in a housing.SOLUTION: A stator cooling flow channel R includes: a first coil cooling flow channel R20 that is provided to a first mold part 41; a first communication hole R1 that is provided to a housing 11, and communicates an external cooling flow channel 100 and the first coil cooling flow channel R20; and a second communication hole that communicates the first coil cooling flow channel R20 and a core cooling flow channel R10. One end part R1a of the first communication hole R1 and one end part of the second communication hole are opened in an inner surface of the housing 11. The first coil cooling flow channel R20 is a penetration hole for penetrating a first mold part 41. In an outer surface of the first mold part 41 contacted to the inner surface of the housing 11, a first end part R20a of the first coil cooling flow channel R20 is connected to the one end part R1a of the first communication hole R1, and the second end part of the first coil cooling flow channel R20 is connected to the one end part of the second communication hole.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a motor.

Background Art

[0002] A motor includes a motor unit that rotates a rotating shaft and a housing that houses the motor unit. The motor unit has a rotor, a stator, and a resin mold part. The rotating shaft is fixed to the rotor. The rotating shaft rotates integrally with the rotor. The rotating shaft is rotatably supported by a bearing. The stator has a cylindrical stator core and a coil wound around the stator core. The coil has a pair of coil ends located at both end faces in the axial direction of the stator core. The resin mold part molds the coil with resin.

[0003] When the motor is driven, the temperature of the stator rises. Therefore, it is required to suppress the temperature rise of the stator by cooling the stator. For example, in the pump device described in Patent Document 1, the stator is cooled as follows. Refrigerant is inhaled into the housing from an intake port provided in the housing. Then, the refrigerant inhaled into the housing flows through a space in the housing where the motor unit is not arranged. The stator is cooled by the refrigerant flowing through the space in the housing where the motor unit is not arranged.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, if the refrigerant flows into the space within the housing where the motor is not located, as in Patent Document 1, the following two problems arise. The first problem is that the refrigerant coming into contact with the rotor causes power loss in the rotor. The second problem is that a seal is required between the rotating shaft and the bearing. To solve the above problems, for example, it is conceivable to cool the stator without flowing the refrigerant into the space within the housing where the motor is not located. However, in this case, there is a risk of insufficient cooling of the coil ends. [Means for solving the problem]

[0006] A motor to solve the above problems comprises a motor section and a housing housing the motor section, the motor section having a rotor, a stator having a cylindrical stator core and coils wound around the stator core, and a resin molded section for molding the coils with resin, the coils having a first coil end located on a first end face which is one end face in the axial direction of the stator core, and a second coil end located on a second end face which is the other end face in the axial direction of the stator core, the resin molded section having a first molded section for molding the first coil end and a second molded section for molding the second coil end, and a stator cooling passage is provided for cooling the stator by the flow of a coolant inside, the stator cooling passage is provided in the housing and has a core cooling passage for cooling the stator core, and is provided in the first molded section and has a first coil The gist of the invention is that the device has a first coil cooling channel for cooling the end, a first communication hole provided in the housing that connects the external refrigerant channel and the first coil cooling channel, a second communication hole provided in the housing that connects the first coil cooling channel and the core cooling channel, and a third communication hole provided in the housing that connects the core cooling channel and the external refrigerant channel, with one end of the first communication hole and one end of the second communication hole opening on the inner surface of the housing, the first coil cooling channel being a through hole penetrating the first mold portion, the outer surface of the first mold portion in contact with the inner surface of the housing, the first end of the first coil cooling channel being connected to one end of the first communication hole on the outer surface of the first mold portion in contact with the inner surface of the housing, and the second end of the first coil cooling channel, which is the end opposite to the first end, being connected to one end of the second communication hole.

[0007] According to the above configuration, the first molding section that molds the first coil end is provided with a first coil cooling channel. Therefore, the first coil end can be cooled by the refrigerant flowing through the first coil cooling channel.

[0008] Furthermore, one end of the first communication hole and one end of the second communication hole are open on the inner surface of the housing. The first coil cooling channel is a through hole that penetrates the first molded portion. The outer surface of the first molded portion is in contact with the inner surface of the housing. On the outer surface of the first molded portion that is in contact with the inner surface of the housing, the first end of the first coil cooling channel is connected to one end of the first communication hole, and the second end of the first coil cooling channel is connected to one end of the second communication hole. In other words, the first coil cooling channel, which is the part of the stator cooling channel provided inside the housing, is in contact with the external refrigerant channel and the core cooling channel, respectively, without being in contact with the space inside the housing where the motor is not located. Therefore, refrigerant does not flow into the space inside the housing where the motor is not located. Thus, the coil ends can be cooled without refrigerant flowing into the space inside the housing where the motor is not located.

[0009] In the motor described above, the first communication hole is an introduction section for introducing the refrigerant from the external refrigerant flow path to the stator cooling flow path, and the refrigerant may flow in the order of the first communication hole, the first coil cooling flow path, the second communication hole, and the core cooling flow path.

[0010] Generally, the heat resistance of the coil ends is lower than that of the stator core, so it is preferable to cool the coil ends preferentially over the stator core. In the above configuration, the refrigerant flows through the first coil cooling channel and then through the core cooling channel. Therefore, the first coil ends can be cooled more effectively compared to the case where the refrigerant flows through the core cooling channel and then through the first coil cooling channel. Consequently, the first coil ends can be cooled preferentially over the stator core.

[0011] In the motor described above, the stator cooling passage further comprises a second coil cooling passage provided in the second mold portion for cooling the second coil end, and a fourth communication hole provided in the housing for connecting the second coil cooling passage and the external refrigerant passage. The third communication hole connects the core cooling passage and the external refrigerant passage via the second coil cooling passage and the fourth communication hole. One end of the third communication hole and one end of the fourth communication hole open on the inner surface of the housing. The second coil cooling passage is a through hole penetrating the second mold portion. The outer surface of the second mold portion abuts against the inner surface of the housing. On the outer surface of the second mold portion abutting against the inner surface of the housing, the first end of the second coil cooling passage is connected to one end of the third communication hole, and the second end, which is the end opposite to the first end of the second coil cooling passage, may be connected to one end of the fourth communication hole.

[0012] According to the above configuration, the second molded section that molds the second coil end is provided with a second coil cooling channel. Therefore, the second coil end can be cooled by the refrigerant flowing through the second coil cooling channel. In this case, since not only the first coil end but also the second coil end is cooled, the temperature rise of the coil can be further suppressed.

[0013] Furthermore, one end of the third communication hole and one end of the fourth communication hole are open on the inner surface of the housing. The second coil cooling passage is a through hole that penetrates the second molded portion. The outer surface of the second molded portion is in contact with the inner surface of the housing. On the outer surface of the second molded portion that is in contact with the inner surface of the housing, the first end of the second coil cooling passage is connected to one end of the third communication hole, and the second end of the second coil cooling passage is connected to one end of the fourth communication hole. In other words, the second coil cooling passage, which is the portion of the stator cooling passage provided inside the housing, is in contact with the external refrigerant passage and the core cooling passage, respectively, without being in contact with the space inside the housing where the motor is not located. Therefore, the second coil end can be cooled without circulating refrigerant in the space inside the housing where the motor is not located.

[0014] In the motor described above, a portion of the first coil end may be exposed within the first coil cooling channel. According to the above configuration, a portion of the first coil end comes into contact with the refrigerant flowing through the first coil cooling channel, and therefore the first coil end is directly cooled by the refrigerant flowing through the first coil cooling channel. Consequently, the cooling effect of the first coil end can be increased compared to the case where the first coil end is cooled by the refrigerant flowing through the first coil cooling channel via the first mold portion.

[0015] In the motor described above, the first coil cooling channel may circulate within the first molded portion in the circumferential direction of the stator core. According to the above configuration, a single first coil cooling channel can cool the first coil ends of multiple coils arranged circumferentially around the stator core. [Effects of the Invention]

[0016] According to the present invention, the coil end can be cooled without circulating refrigerant in the space within the housing where the motor is not located. [Brief explanation of the drawing]

[0017] [Figure 1] This is a cross-sectional view showing the motor in the first embodiment. [Figure 2] This is a cross-sectional view along line 2-2 in Figure 1, showing the motor in the first embodiment. [Figure 3] This is a rear view showing the stator and resin molded part in the first embodiment. [Figure 4] This is a front view showing the stator and resin molded part in the first embodiment. [Figure 5] This is a cross-sectional view showing the motor in the first embodiment. [Figure 6] This is a rear view showing the stator and resin molded part in the second embodiment. [Figure 7]It is a front view showing a stator and a resin mold part in the second embodiment. [Figure 8] It is a cross-sectional view showing a motor in the second embodiment. [Figure 9] It is a cross-sectional view showing a motor in a modification example.

Mode for Carrying Out the Invention

[0018] [First Embodiment] Hereinafter, a first embodiment in which a motor is embodied will be described with reference to FIGS. 1 to 5. As shown in FIGS. 1 and 2, the motor 10 includes a housing 11, a motor part 12, a rotating shaft 13, and two bearings 14.

[0019] [Housing] The housing 11 is made of metal. The housing 11 of the present embodiment is made of aluminum. The housing 11 of the present embodiment has a housing body 21, a cover 22, a first flow path forming member 23, a second flow path forming member 24, and a third flow path forming member 25. The housing body 21 has a bottomed cylindrical shape having a disk-shaped bottom wall 26 and a peripheral wall 27 extending cylindrically from the outer peripheral portion of the bottom wall 26. The housing body 21 has a cylindrical first boss 28. The first boss 28 protrudes from the central portion of the inner surface 26a of the bottom wall 26. [[ID=!25]]

[0020] The cover 22 is disk-shaped. The cover 22 is connected to the opening-side end of the housing body 21. The cover 22 closes the opening of the housing body 21. The cover 22 has a shaft insertion hole 22h. The shaft insertion hole 22h penetrates the cover 22 in the plate thickness direction. The cover 22 has a cylindrical second boss 29. The second boss 29 protrudes from the cover 22 toward the bottom wall 26. The inside of the second boss 29 communicates with the shaft insertion hole 22h.

[0021] The first channel forming member 23 is cylindrical. The first channel forming member 23 is located on the outer circumference of the peripheral wall 27. The axial direction of the first channel forming member 23 coincides with the axial direction of the peripheral wall 27. A gap is provided between the inner circumferential surface of the first channel forming member 23 and the outer circumferential surface of the peripheral wall 27. The second channel forming member 24 and the third channel forming member 25 are annular. The second channel forming member 24 connects the first axial end 23a of the first channel forming member 23 to the outer circumferential surface of the housing body 21. The third channel forming member 25 connects the second axial end 23b of the first channel forming member 23 to the outer circumferential surface of the cover 22.

[0022] <Motor section> The motor unit 12 is housed within the housing 11. The inside of the housing 11 is a space partitioned by the inner surface of the housing 11. In this embodiment, the inner surface 26a of the bottom wall 26 and the inner surface 27a of the peripheral wall 27 are the inner surfaces of the housing body 21. The inner surface of the housing body 21 and the inner surface 22a of the cover 22 are the inner surfaces of the housing 11. In this embodiment, the inside of the housing 11 is a space partitioned by the inner surface 26a of the bottom wall 26, the inner surface 27a of the peripheral wall 27, and the inner surface 22a of the cover 22. The inside of the housing 11 includes an unhoused space S in which the motor unit 12 is not located.

[0023] The motor unit 12 includes a stator 30, a resin molded part 40, and a rotor 50. The stator 30 includes a stator core 31 and a coil 32. As shown in Figure 2, the stator core 31 has a yoke 33 and a plurality of teeth 34. The yoke 33 is cylindrical. Hereinafter, the axial, radial, and circumferential directions of the yoke 33 will also be referred to as the axial, radial, and circumferential directions of the stator core 31, respectively. The outer circumferential surface of the yoke 33 is fixed to the inner circumferential surface 27a of the circumferential wall 27. In this way, the stator core 31 is fixed to the housing 11. The axial direction of the stator core 31 coincides with the axial direction of the circumferential wall 27.

[0024] Each tooth 34 extends from the inner circumferential surface of the yoke 33. Each tooth 34 extends in the axial direction of the yoke 33. Multiple teeth 34 are spaced apart in the circumferential direction of the yoke 33. Each tooth 34 has an extended portion 34a and a flange portion 34b. The extended portion 34a extends from the inner circumferential surface of the yoke 33 along the radial direction of the yoke 33. The flange portion 34b protrudes from the end of the extended portion 34a opposite to the yoke 33 to both sides of the stator core 31 in the circumferential direction.

[0025] As shown in Figure 1, the stator core 31 has a first end face 31a and a second end face 31b. The first end face 31a is one axial end face of the stator core 31, and the second end face 31b is the other axial end face of the stator core 31. The first end face 31a of the stator core 31 is located on the bottom wall 26 side of the housing body 21. The second end face 31b of the stator core 31 is located on the cover 22 side.

[0026] The coil 32 is made of a conductor. In this embodiment, the coil 32 is made of copper wire. The coil 32 is wound around the stator core 31. More specifically, the coil 32 is concentrated on each of the extended portions 34a of the multiple teeth 34. Therefore, the stator 30 has the same number of coils 32 as teeth 34. The coils 32 are arranged in the circumferential direction of the stator core 31.

[0027] As shown in Figures 1 and 2, each coil 32 has a pair of coil ends 35 and a pair of main parts 36. The pair of coil ends 35 are located on both sides of the teeth 34 in the axial direction of the stator core 31. In the following description, of the pair of coil ends 35, the coil end 35 located on the first end face 31a of the stator core 31 will be referred to as the first coil end 35a, and the coil end 35 located on the second end face 31b of the stator core 31 will be referred to as the second coil end 35b. The pair of main parts 36 are located on both sides of the extended portion 34a of the teeth 34 in the circumferential direction of the yoke 33.

[0028] The resin molded section 40 molds the coil 32 with resin. The coil 32 is located inside the resin molded section 40. Therefore, the coil 32 is not exposed inside the housing 11. The resin molded section 40 has a first molded section 41, a second molded section 42, and a third molded section 43.

[0029] As shown in Figures 1 and 3, the first molded portion 41 molds the first coil end 35a. The first coil end 35a is located within the first molded portion 41. The first molded portion 41 extends in an annular shape along the circumferential direction of the stator core 31. The first molded portion 41 is located between the first end face 31a of the stator core 31 and the inner surface 26a of the bottom wall 26.

[0030] The first molded portion 41 has a first end face 41a facing the inner surface 26a of the bottom wall 26. The first end face 41a is the outer surface of the first molded portion 41. In this embodiment, the first end face 41a is in contact with the inner surface 26a of the bottom wall 26. Therefore, the first end face 41a of the first molded portion 41 is in contact with the inner surface of the housing 11.

[0031] Furthermore, the first molded portion 41 has a first outer peripheral surface 41b that faces the inner peripheral surface 27a of the peripheral wall 27. The first outer peripheral surface 41b is the outer surface of the first molded portion 41. The first outer peripheral surface 41b is in contact with the inner peripheral surface 27a of the peripheral wall 27. Therefore, the first outer peripheral surface 41b of the first molded portion 41 is in contact with the inner surface of the housing 11.

[0032] As shown in Figures 1 and 4, the second molded portion 42 molds the second coil end 35b. The second coil end 35b is located within the second molded portion 42. The second molded portion 42 extends in an annular shape along the circumferential direction of the stator core 31. The second molded portion 42 is located between the second end face 31b of the stator core 31 and the inner surface 22a of the cover 22.

[0033] The second molded portion 42 has a second end face 42a that faces the inner surface 22a of the cover 22. The second end face 42a is the outer surface of the second molded portion 42. In this embodiment, the second end face 42a is in contact with the inner surface 22a of the cover 22. Therefore, the second end face 42a of the second molded portion 42 is in contact with the inner surface of the housing 11.

[0034] Furthermore, the second molded portion 42 has a second outer peripheral surface 42b that faces the inner peripheral surface 27a of the peripheral wall 27. The second outer peripheral surface 42b is the outer surface of the second molded portion 42. The second outer peripheral surface 42b is in contact with the inner peripheral surface 27a of the peripheral wall 27. Therefore, the second outer peripheral surface 42b of the second molded portion 42 is in contact with the inner surface of the housing 11.

[0035] As shown in Figure 2, the third molded portion 43 molds the main portion 36. The main portion 36 is located within the third molded portion 43. The third molded portion 43 is located in the space enclosed by the inner circumferential surface of the yoke 33 and the extended portions 34a of a pair of teeth 34 adjacent to each other in the circumferential direction of the yoke 33. The flange portion 34b of each tooth 34 protrudes from the third molded portion 43.

[0036] As shown in Figures 1 and 2, the rotor 50 is positioned inside the stator 30. When a rotating magnetic field is generated in the stator 30 by energizing the coil 32 of the stator 30, the rotor 50 rotates.

[0037] The rotor 50 of this embodiment includes a cylindrical member 51 and a permanent magnet 52. The cylindrical member 51 is cylindrical in shape. The cylindrical member 51 is, for example, made of a titanium alloy. The permanent magnet 52 is cylindrical in shape. The axial dimension of the permanent magnet 52 is shorter than the axial dimension of the cylindrical member 51. The permanent magnet 52 is magnetized radially. The permanent magnet 52 is located inside the cylindrical member 51. The permanent magnet 52 is fixed to the cylindrical member 51, for example, by press-fitting it into the inside of the cylindrical member 51. The axial direction of the cylindrical member 51 coincides with the axial direction of the permanent magnet 52. Both axial ends of the cylindrical member 51 protrude axially on both sides more than the axial end faces of the permanent magnet 52. The outer circumferential surface of the cylindrical member 51 faces the flange 34b of the teeth 34.

[0038] <Rotation axis> As shown in Figure 1, the rotating shaft 13 is fixed to the rotor 50. When the rotor 50 rotates, the rotating shaft 13 rotates together with the rotor 50. In other words, the motor unit 12 rotates the rotating shaft 13.

[0039] The rotating shaft 13 of this embodiment has a first shaft member 13a and a second shaft member 13b. The first shaft member 13a and the second shaft member 13b are cylindrical in shape. The first shaft member 13a and the second shaft member 13b are made of, for example, iron.

[0040] The first shaft member 13a is inserted inside the cylindrical member 51 at its first axial end. The first shaft member 13a is fixed to the rotor 50, for example, by press-fitting it into the cylindrical member 51. The first shaft member 13a rotates integrally with the rotor 50. The first shaft member 13a is inserted inside the first boss 28. The bearing 14 is positioned between the outer circumferential surface of the first shaft member 13a and the inner circumferential surface of the first boss 28. The bearing 14 is a radial bearing. The bearing 14 rotatably supports the first shaft member 13a.

[0041] The second shaft member 13b is inserted into the inside of the cylindrical member 51 at its second axial end. The second shaft member 13b is fixed to the rotor 50, for example, by press-fitting it into the inside of the cylindrical member 51. The second shaft member 13b rotates integrally with the rotor 50. The second shaft member 13b is inserted into the inside of the second boss 29 and through the shaft insertion hole 22h. A portion of the second shaft member 13b protrudes outside the housing 11. The bearing 14 is positioned between the outer circumferential surface of the second shaft member 13b and the inner circumferential surface of the second boss 29. The bearing 14 is a radial bearing. The bearing 14 rotatably supports the second shaft member 13b.

[0042] <Cooling channel configuration> The motor 10 is provided with a stator cooling channel R for cooling the stator 30. The stator 30 is cooled by a refrigerant flowing through the stator cooling channel R. Examples of refrigerants include LLC and fluorocarbons. In this embodiment, the refrigerant is LLC.

[0043] One end of the stator cooling channel R is connected to one end of the external refrigerant channel 100, and the other end of the stator cooling channel R is connected to the other end of the external refrigerant channel 100. A pump P is provided in the middle of the external refrigerant channel 100. The external refrigerant channel 100 consists of a first refrigerant channel 101 and a second refrigerant channel 102. One end of the first refrigerant channel 101 is connected to the discharge port Pa of the pump P, and the other end of the first refrigerant channel 101 is connected to one end of the stator cooling channel R. One end of the second refrigerant channel 102 is connected to the suction port Pb of the pump P, and the other end of the second refrigerant channel 102 is connected to the other end of the stator cooling channel R. The pump P discharges the refrigerant drawn in from the second refrigerant channel 102 into the first refrigerant channel 101. The refrigerant flows in the order of first refrigerant channel 101, stator cooling channel R, and second refrigerant channel 102. The external refrigerant flow path 100 and the stator cooling flow path R constitute a circulation path through which the refrigerant circulates.

[0044] As shown in Figures 1 and 2, the stator cooling channel R has a core cooling channel R10 that cools the stator core 31. The core cooling channel R10 is provided in the housing 11. In this embodiment, the core cooling channel R10 is partitioned by the outer circumferential surface of the peripheral wall 27, the inner circumferential surface of the first channel forming member 23, the second channel forming member 24, and the third channel forming member 25. The core cooling channel R10 is a cylindrical space.

[0045] As shown in Figure 3, the stator cooling channel R has a first coil cooling channel R20 that cools the first coil end 35a. The first coil cooling channel R20 is provided in the first molded portion 41. The first coil cooling channel R20 is the portion of the stator cooling channel R provided inside the housing 11. The first coil cooling channel R20 is a through hole that penetrates the first molded portion 41.

[0046] The first coil cooling channel R20 of this embodiment has a first axial path R21, a first circumferential path R22, and a first radial path R23. The first axial path R21 extends along the axial direction of the stator core 31. The first circumferential path R22 circulates in the circumferential direction of the stator core 31 within the first molded portion 41. The first radial path R23 extends along the radial direction of the stator core 31.

[0047] As shown in Figure 1, in this embodiment, a portion of the first coil end 35a is exposed within the first circumference R22. Therefore, a portion of the first coil end 35a is exposed within the first coil cooling channel R20.

[0048] As shown in Figure 3, one end of the first circumferential path R22 is connected to one end of the first axial path R21, and the other end of the first circumferential path R22 is connected to one end of the first radial path R23. The end of the first axial path R21 opposite to the end connected to the first circumferential path R22 constitutes the first end R20a of the first coil cooling channel R20. In this embodiment, the first end R20a of the first coil cooling channel R20 is open at the first end face 41a of the first molded portion 41. The end of the first radial path R23 opposite to the end connected to the first circumferential path R22 constitutes the second end R20b of the first coil cooling channel R20. The second end R20b of the first coil cooling channel R20 is open at the first outer peripheral surface 41b of the first molded portion 41.

[0049] As shown in Figure 4, the stator cooling channel R has a second coil cooling channel R30 that cools the second coil end 35b. The second coil cooling channel R30 is provided in the second molded portion 42. The second coil cooling channel R30 is the portion of the stator cooling channel R provided inside the housing 11. The second coil cooling channel R30 is a through hole that penetrates the second molded portion 42.

[0050] The second coil cooling channel R30 of this embodiment has a second radial channel R31, a second circumferential channel R32, and a second axial channel R33. The second radial channel R31 extends along the radial direction of the stator core 31. The second circumferential channel R32 circulates within the second molded portion 42 in the circumferential direction of the stator core 31. The second axial channel R33 extends along the axial direction of the stator core 31.

[0051] As shown in Figure 1, in this embodiment, a portion of the second coil end 35b is exposed within the second circulation path R32. Therefore, a portion of the second coil end 35b is exposed within the second coil cooling channel R30.

[0052] As shown in Figure 4, one end of the second circumferential path R32 is connected to one end of the second radial path R31, and the other end of the second circumferential path R32 is connected to one end of the second axial path R33. The end of the second radial path R31 opposite to the end connected to the second circumferential path R32 constitutes the first end R30a of the second coil cooling channel R30. The first end R30a of the second coil cooling channel R30 is open at the second outer peripheral surface 42b of the second molded portion 42. The end of the second axial path R33 opposite to the end connected to the second circumferential path R32 constitutes the second end R30b of the second coil cooling channel R30. In this embodiment, the second end R30b of the second coil cooling channel R30 is open at the second end surface 42a of the second molded portion 42.

[0053] The first molded portion 41 of this embodiment is formed by joining a first resin member and a second resin member to each other. Specifically, the first resin member is molded to have a first axial path R21 and the bottom wall 26 side half of the first circumferential path R22 and the first radial path R23. The second resin member is molded to have the stator core 31 side half of the first circumferential path R22 and the first radial path R23. The first resin member and the second resin member are joined to each other such that the first circumferential path R22 of the first resin member and the first circumferential path R22 of the second resin member face each other, and the first radial path R23 of the first resin member and the first radial path R23 of the second resin member face each other.

[0054] Similarly, the second molded portion 42 of this embodiment is formed by joining a third resin member and a fourth resin member to each other. Specifically, the third resin member is molded to have the stator core 31 side half of the second path R31 and the second circumferential path R32. The fourth resin member is molded to have the cover 22 side half of the second path R31 and the second circumferential path R32, and the second shaft path R33. The third resin member and the fourth resin member are joined to each other such that the second path R31 of the third resin member and the second path R31 of the fourth resin member face each other, and the second circumferential path R32 of the third resin member and the second circumferential path R32 of the fourth resin member face each other.

[0055] The second resin member and the third resin member may be integrally molded with the third molded portion 43. As shown in Figures 1 and 5, the stator cooling channel R has a first communication hole R1, a second communication hole R2, a third communication hole R3, and a fourth communication hole R4. The first communication hole R1, the second communication hole R2, the third communication hole R3, and the fourth communication hole R4 are each provided in the housing 11.

[0056] The first connecting hole R1 connects the external refrigerant flow path 100 to the first coil cooling flow path R20. The second connecting hole R2 connects the first coil cooling flow path R20 to the core cooling flow path R10. The third connecting hole R3 connects the core cooling flow path R10 to the second coil cooling flow path R30. The fourth connecting hole R4 connects the second coil cooling flow path R30 to the external refrigerant flow path 100.

[0057] The phrase "A connects B and C" includes cases where only A is present between B and C, i.e., A is adjacent to both B and C, and cases where, in addition to A, other pathways are present between B and C. For example, when A and D are present between B and C, and A connects B and C via D, this is also included in "A connects B and C".

[0058] In this embodiment, the third communication hole R3 connects the core cooling channel R10 and the external refrigerant channel 100 via the second coil cooling channel R30 and the fourth communication hole R4. Therefore, the third communication hole R3 connects the core cooling channel R10 and the external refrigerant channel 100. The "third communication hole R3" in this embodiment corresponds to the "third communication hole that connects the core cooling channel and the external refrigerant channel" in the claim.

[0059] As shown in Figure 1, the first communication hole R1 in this embodiment penetrates the bottom wall 26 in the thickness direction. One end R1a of the first communication hole R1 opens on the inner surface of the housing 11. In this embodiment, one end R1a of the first communication hole R1 opens on the inner surface 26a of the bottom wall 26. The other end R1b of the first communication hole R1, which is the end opposite to the one end R1a, opens on the outer surface of the bottom wall 26.

[0060] The other end R1b of the first communication hole R1 is connected to one end of the external refrigerant flow path 100 on the outer surface of the bottom wall 26. In this embodiment, the other end R1b of the first communication hole R1 is connected to the end on the outer surface of the bottom wall 26 that is opposite to the end of the first refrigerant flow path 101 that is connected to the discharge port Pa of the pump P. The first communication hole R1 is an introduction section for introducing refrigerant into the stator cooling flow path R.

[0061] The first end R20a of the first coil cooling channel R20 is connected to one end R1a of the first communication hole R1 at the outer surface of the first molded portion 41 that abuts against the inner surface of the housing 11. In this embodiment, the first end R20a of the first coil cooling channel R20 is connected to one end R1a of the first communication hole R1 at the first end surface 41a of the first molded portion 41 that abuts against the inner surface 26a of the bottom wall 26.

[0062] As shown in Figure 5, the second communication hole R2 in this embodiment penetrates the peripheral wall 27 radially. One end R2a of the second communication hole R2 opens on the inner surface of the housing 11. The other end R2b of the second communication hole R2 opens on the inner peripheral surface 27a of the peripheral wall 27. The other end R2b of the second communication hole R2, which is the end opposite to the one end R2a, opens on the outer peripheral surface of the peripheral wall 27 that defines the core cooling channel R10.

[0063] The second end R20b of the first coil cooling channel R20 is connected to one end R2a of the second communication hole R2 on the outer surface of the first molded portion 41 that abuts against the inner surface of the housing 11. The second end R20b of the first coil cooling channel R20 is connected to one end R2a of the second communication hole R2 on the first outer surface 41b of the first molded portion 41 that abuts against the inner circumferential surface 27a of the peripheral wall 27.

[0064] In this embodiment, the third communication hole R3 penetrates the peripheral wall 27 radially. One end R3a of the third communication hole R3 opens on the inner surface of the housing 11. The other end R3b of the third communication hole R3 opens on the inner peripheral surface 27a of the peripheral wall 27. The other end R3b of the third communication hole R3, which is the end opposite to the end R3a, opens on the outer peripheral surface of the peripheral wall 27 that partitions the core cooling channel R10. The third communication hole R3 is located on the opposite side of the peripheral wall 27 from the second communication hole R2, with the surface to which the stator core 31 is fixed in the axial direction.

[0065] The first end R30a of the second coil cooling channel R30 is connected to one end R3a of the third communication hole R3 at the outer surface of the second molded portion 42, which is in contact with the inner surface of the housing 11. The first end R30a of the second coil cooling channel R30 is connected to one end R3a of the third communication hole R3 at the second outer surface 42b of the second molded portion 42, which is in contact with the inner circumferential surface 27a of the peripheral wall 27.

[0066] As shown in Figure 1, the fourth communication hole R4 in this embodiment penetrates the cover 22 in the thickness direction. One end R4a of the fourth communication hole R4 opens on the inner surface of the housing 11. In this embodiment, one end R4a of the fourth communication hole R4 opens on the inner surface 22a of the cover 22. The other end R4b of the fourth communication hole R4, which is the end opposite to the one end R4a, opens on the outer surface of the cover 22.

[0067] The other end R4b of the fourth communication hole R4 is connected to the other end of the external refrigerant flow path 100 on the outer surface of the cover 22. In this embodiment, the other end R4b of the fourth communication hole R4 is connected to the end on the outer surface of the cover 22 that is opposite to the end of the second refrigerant flow path 102 that is connected to the suction port Pb of the pump P. The fourth communication hole R4 is a discharge section for discharging refrigerant from the stator cooling flow path R to the external refrigerant flow path 100.

[0068] The second end R30b of the second coil cooling channel R30 is connected to one end R4a of the fourth communication hole R4 at the outer surface of the second molded portion 42 which abuts against the inner surface of the housing 11. In this embodiment, the second end R30b of the second coil cooling channel R30 is connected to one end R4a of the fourth communication hole R4 at the second end surface 42a of the second molded portion 42 which abuts against the inner surface 22a of the cover 22.

[0069] <Refrigerant flow> The following describes in detail the flow of refrigerant in the stator cooling channel R of this embodiment. The refrigerant flows from the first refrigerant passage 101 through the first communication hole R1 into the first coil cooling passage R20. The refrigerant flows through the first coil cooling passage R20 in the order of the first axial passage R21, the first circumferential passage R22, and the first radial passage R23. The first coil ends 35a of the multiple coils 32 arranged circumferentially around the stator core 31 are cooled by the refrigerant flowing through the first circumferential passage R22. Because the coils 32 have high thermal conductivity, when the first coil ends 35a are cooled, the main section 36 is also cooled.

[0070] Next, the refrigerant flows from the first coil cooling channel R20 through the second communication hole R2 into the core cooling channel R10. The refrigerant flows through the core cooling channel R10 axially along the stator core 31 from the second communication hole R2 towards the third communication hole R3. The refrigerant also flows circumferentially along the stator core 31 within the core cooling channel R10. The yoke 33 of the stator core 31 is cooled by the refrigerant flowing through the core cooling channel R10 via the peripheral wall 27.

[0071] Next, the refrigerant flows from the core cooling channel R10 through the third communication hole R3 into the second coil cooling channel R30. The refrigerant flows through the second coil cooling channel R30 in the order of the second radial path R31, the second circumferential path R32, and the second axial path R33. The second coil ends 35b of the multiple coils 32 arranged circumferentially around the stator core 31 are cooled by the refrigerant flowing through the second circumferential path R32. Because the coils 32 have high thermal conductivity, when the second coil ends 35b are cooled, the main section 36 is also cooled.

[0072] The refrigerant then flows out from the second coil cooling channel R30 through the fourth communication hole R4 into the second refrigerant channel 102. The refrigerant that flows into the second refrigerant channel 102 is cooled by a cooling device (not shown) and then returns to the first refrigerant channel 101 by the operation of pump P.

[0073] [Operation and Effects of the First Embodiment] The operation and effects of this embodiment will now be explained. (1-1) The first molded section 41, which molds the first coil end 35a, is provided with a first coil cooling channel R20. Therefore, the first coil end 35a is cooled by the refrigerant flowing through the first coil cooling channel R20. The first coil cooling channel R20 is a through-hole that penetrates the inside of the first molded section 41.

[0074] The housing 11 is provided with a first communication hole R1, a second communication hole R2, and a third communication hole R3. The first communication hole R1 connects the external refrigerant flow path 100 to the first coil cooling flow path R20. The second communication hole R2 connects the first coil cooling flow path R20 to the core cooling flow path R10. The third communication hole R3 connects the core cooling flow path R10 to the external refrigerant flow path 100. One end R1a of the first communication hole R1 opens on the inner surface 26a of the bottom wall 26. One end R2a of the second communication hole R2 opens on the inner surface 27a of the peripheral wall 27.

[0075] The first end R20a of the first coil cooling channel R20 is connected to one end R1a of the first communication hole R1 at the first end face 41a of the first molded portion 41, which abuts against the inner surface 26a of the bottom wall 26. The second end R20b of the first coil cooling channel R20 is connected to one end R2a of the second communication hole R2 at the first outer surface 41b of the first molded portion 41, which abuts against the inner surface 27a of the peripheral wall 27.

[0076] In other words, the first coil cooling passage R20, which is the portion of the stator cooling passage R provided within the housing 11, communicates with the external refrigerant passage 100 and the core cooling passage R10, respectively, without communicating with the non-contained space S, which is the space within the housing 11 where the motor unit 12 is not located. Therefore, the first coil end 35a can be cooled without refrigerant flowing through the non-contained space S. As a result, power loss of the rotor 50 caused by refrigerant flowing over the rotor 50 can be avoided. In addition, a seal between the rotating shaft 13 and the bearing 14 is unnecessary.

[0077] (1-2) Generally, the heat resistance of the coil end 35 is lower than that of the stator core 31, so it is preferable to cool the coil end 35 preferentially over the stator core 31. In this embodiment, the first communication hole R1 is an introduction part for introducing refrigerant from the external refrigerant flow path 100 to the stator cooling flow path R. The refrigerant flows in this order through the first communication hole R1, the first coil cooling flow path R20, the second communication hole R2, and the core cooling flow path R10. That is, the refrigerant flows through the first coil cooling flow path R20 and then through the core cooling flow path R10. Therefore, the first coil end 35a can be cooled more effectively compared to the case where the refrigerant flows through the core cooling flow path R10 and then through the first coil cooling flow path R20. Thus, the first coil end 35a can be cooled preferentially over the stator core 31.

[0078] (1-3) The second molding section 42, which molds the second coil end 35b, is provided with a second coil cooling channel R30. Therefore, the second coil end 35b is cooled by the coolant flowing through the second coil cooling channel R30. In this case, since not only the first coil end 35a but also the second coil end 35b is cooled, the temperature rise of the coil 32 can be further suppressed.

[0079] The housing 11 is provided with a fourth communication hole R4 that connects the second coil cooling passage R30 to the external refrigerant passage 100. The third communication hole R3 connects the core cooling passage R10 to the external refrigerant passage 100 via the second coil cooling passage R30 and the fourth communication hole R4. The second coil cooling passage R30 is a through hole that penetrates the second molded portion 42. One end R3a of the third communication hole R3 opens on the inner surface 27a of the peripheral wall 27. One end R4a of the fourth communication hole R4 opens on the inner surface 22a of the cover 22.

[0080] The first end R30a of the second coil cooling channel R30 is connected to one end R3a of the third communication hole R3 at the second outer surface 42b of the second molded portion 42, which abuts against the inner surface 27a of the peripheral wall 27. The second end R30b of the second coil cooling channel R30 is connected to one end R4a of the fourth communication hole R4 at the second end surface 42a of the second molded portion 42, which abuts against the inner surface 22a of the cover 22.

[0081] In other words, the second coil cooling channel R30, which is the portion of the stator cooling channel R located within the housing 11, communicates with the external refrigerant channel 100 and the core cooling channel R10, respectively, without communicating with the non-contained space S. Therefore, the second coil end 35b can be cooled without circulating refrigerant through the non-contained space S.

[0082] (1-4) A portion of the first coil end 35a is exposed within the first coil cooling channel R20. As a result, a portion of the first coil end 35a comes into contact with the refrigerant flowing through the first coil cooling channel R20, and the first coil end 35a is directly cooled by the refrigerant flowing through the first coil cooling channel R20. Therefore, the cooling effect of the first coil end 35a can be increased compared to the case where the first coil end 35a is cooled by the refrigerant flowing through the first coil cooling channel R20 via the first mold portion 41.

[0083] Similarly, a portion of the second coil end 35b is exposed within the second coil cooling channel R30. As a result, a portion of the second coil end 35b comes into contact with the coolant flowing through the second coil cooling channel R30, and the second coil end 35b is directly cooled by the coolant flowing through the second coil cooling channel R30. Therefore, the cooling effect of the second coil end 35b can be increased compared to the case where the second coil end 35b is cooled by the coolant flowing through the second coil cooling channel R30 via the second mold portion 42.

[0084] (1-5) As a configuration for cooling the coil end 35 without flowing refrigerant into the non-contained space S, for example, a cooling channel extending in the axial direction of the stator core 31 can be provided within the third molded portion 43. In this case, the main portion 36 is cooled by the refrigerant flowing through the cooling channel, and the coil end 35 is also cooled. However, since the cooling channel is formed between adjacent coils 32 in the circumferential direction of the stator core 31, the cooling channel tends to become narrow. Also, if the cooling channel is widened, the packing ratio of the coils 32 decreases.

[0085] In contrast, in this embodiment, the first coil end 35a is cooled by the refrigerant flowing through the first coil cooling channel R20. The second coil end 35b is cooled by the refrigerant flowing through the second coil cooling channel R30. In this case, the coil ends 35 can be cooled without forming a cooling channel between adjacent coils 32 in the circumferential direction of the stator core 31, thus avoiding a decrease in the coil occupancy rate due to the formation of a refrigerant channel.

[0086] (1-6) The core cooling channel R10, the first coil cooling channel R20, and the second coil cooling channel R30 are in communication with each other. Therefore, a single pump P can supply refrigerant to the core cooling channel R10, the first coil cooling channel R20, and the second coil cooling channel R30. Consequently, there is no need to provide a separate pump P for each channel, as in the case where the core cooling channel R10, the first coil cooling channel R20, and the second coil cooling channel R30 are independently provided, thus reducing the number of pumps P.

[0087] (1-7) The first coil cooling channel R20 has a first circumferential path R22 that circulates in the circumferential direction of the stator core 31 within the first mold portion 41. Therefore, one first coil cooling channel R20 can cool the first coil ends 35a of multiple coils 32 that are arranged in the circumferential direction of the stator core 31 together.

[0088] Similarly, the second coil cooling channel R30 has a second circumferential path R32 that circulates in the circumferential direction of the stator core 31 within the second mold portion 42. Therefore, a single second coil cooling channel R30 can cool the second coil ends 35b of multiple coils 32 arranged in the circumferential direction of the stator core 31 together.

[0089] [Second Embodiment] The second embodiment of the motor will be described below with reference to Figures 6 to 8. In the second embodiment, only the configuration of the stator cooling channel R differs from that of the first embodiment. Therefore, a detailed explanation of the same configuration as in the first embodiment will be omitted.

[0090] As shown in Figure 6, the stator cooling channel R has a plurality of first coil cooling channels R20. In this embodiment, the number of first coil cooling channels R20 is the same as the number of coils 32. The plurality of first coil cooling channels R20 are spaced apart in the circumferential direction of the stator core 31. The first coil cooling channels R20 are provided at positions corresponding to the first coil ends 35a in the circumferential direction of the stator core 31. The first coil cooling channels R20 are aligned with the first coil ends 35a in the axial direction of the stator core 31.

[0091] Each first coil cooling channel R20 is a through-hole that penetrates the first molded portion 41. In this embodiment, each first coil cooling channel R20 extends linearly so as to be inclined with respect to both the axial and radial directions of the stator core 31. The first end R20a of each first coil cooling channel R20 opens at the first end face 41a of the first molded portion 41. The second end R20b of each first coil cooling channel R20 opens at the first outer peripheral surface 41b of the first molded portion 41.

[0092] As shown in Figure 7, the stator cooling channel R has a plurality of second coil cooling channels R30. In this embodiment, the number of second coil cooling channels R30 is the same as the number of coils 32. The plurality of second coil cooling channels R30 are spaced apart in the circumferential direction of the stator core 31. The second coil cooling channels R30 are provided at positions corresponding to the second coil ends 35b in the circumferential direction of the stator core 31. The second coil cooling channels R30 are aligned with the second coil ends 35b in the axial direction of the stator core 31.

[0093] Each second coil cooling channel R30 is a through-hole that penetrates the second molded portion 42. In this embodiment, each second coil cooling channel R30 extends linearly so as to be inclined with respect to both the axial and radial directions of the stator core 31. The first end R30a of each second coil cooling channel R30 opens at the second outer peripheral surface 42b of the second molded portion 42. The second end R30b of each second coil cooling channel R30 opens at the second end surface 42a of the second molded portion 42.

[0094] As shown in Figure 8, the stator cooling channel R has a plurality of first connecting holes R1, a plurality of second connecting holes R2, a plurality of third connecting holes R3, and a plurality of fourth connecting holes R4. In this embodiment, the number of first connecting holes R1 and second connecting holes R2 is the same as the number of first coil cooling channels R20. The number of third connecting holes R3 and fourth connecting holes R4 is the same as the number of second coil cooling channels R30. Note that in Figure 8, two of each of the first connecting holes R1, second connecting holes R2, third connecting holes R3, and fourth connecting holes R4 are shown.

[0095] Multiple first communication holes R1 are arranged at intervals in the circumferential direction of the stator core 31. The first communication holes R1 are located in the circumferential direction of the stator core 31, corresponding to the first end R20a of the first coil cooling channel R20. Each first communication hole R1 penetrates the bottom wall 26 in the thickness direction. One end R1a of each first communication hole R1 opens on the inner surface 26a of the bottom wall 26. The other end R1b of each first communication hole R1, which is the end opposite to the one end R1a, opens on the outer surface of the bottom wall 26. The first end R20a of the first coil cooling channel R20 is connected to one end R1a of the first communication hole R1 at the first end face 41a of the first molded portion 41, which abuts against the inner surface 26a of the bottom wall 26.

[0096] Multiple second communication holes R2 are arranged at intervals in the circumferential direction of the stator core 31. The second communication holes R2 are located in the circumferential direction of the stator core 31, corresponding to the second end R20b of the first coil cooling channel R20. Each second communication hole R2 penetrates the circumferential wall 27 radially. One end R2a of each second communication hole R2 opens on the inner circumferential surface 27a of the circumferential wall 27. The other end R2b of each second communication hole R2, which is the end opposite to the one end R2a, opens on the outer circumferential surface of the circumferential wall 27 that defines the core cooling channel R10. The second end R20b of the first coil cooling channel R20 is connected to one end R2a of the second communication hole R2 at the first outer circumferential surface 41b of the first molded portion 41, which abuts against the inner circumferential surface 27a of the circumferential wall 27.

[0097] Multiple third communication holes R3 are arranged at intervals in the circumferential direction of the stator core 31. The third communication holes R3 are located in the circumferential direction of the stator core 31, corresponding to the first end R30a of the second coil cooling channel R30. Each third communication hole R3 penetrates the circumferential wall 27 radially. One end R3a of each third communication hole R3 opens on the inner circumferential surface 27a of the circumferential wall 27. The other end R3b of each third communication hole R3, which is the end opposite to the one end R3a, opens on the outer circumferential surface of the circumferential wall 27 that partitions the core cooling channel R10. Each third communication hole R3 is located on the opposite side of the circumferential wall 27 from the second communication hole R2, with the surface on which the stator core 31 is fixed in the axial direction. The first end R30a of the second coil cooling channel R30 is connected to one end R3a of the third communication hole R3 at the second outer surface 42b of the second molded portion 42, which abuts against the inner surface 27a of the peripheral wall 27.

[0098] Multiple fourth communication holes R4 are spaced apart in the circumferential direction of the stator core 31. The fourth communication holes R4 are located in the circumferential direction of the stator core 31, corresponding to the second end R30b of the second coil cooling channel R30. Each fourth communication hole R4 penetrates the cover 22 in the thickness direction. One end R4a of each fourth communication hole R4 opens on the inner surface 22a of the cover 22. The other end R4b of each fourth communication hole R4, opposite to the end R4a, opens on the outer surface of the cover 22. The second end R30b of the second coil cooling channel R30 is connected to one end R4a of the fourth communication hole R4 at the second end face 42a of the second molded portion 42, which abuts against the inner surface 22a of the cover 22.

[0099] <Refrigerant flow> The flow of refrigerant in the stator cooling channel R of the second embodiment will be described in detail. The refrigerant flows from the external refrigerant flow path 100 through each first communication hole R1 into each first coil cooling flow path R20. The coils 32 are cooled by the refrigerant flowing through each first coil cooling flow path R20. In the second embodiment, the first coil ends 35a of the multiple coils 32 arranged circumferentially around the stator core 31 are individually cooled by the refrigerant flowing through the first coil cooling flow path R20 located at their corresponding positions.

[0100] Next, the refrigerant flows from each first coil cooling channel R20 through each second communication hole R2 into the core cooling channel R10. The refrigerant flows axially through the core cooling channel R10 from each second communication hole R2 towards each third communication hole R3 of the stator core 31. The yoke 33 of the stator core 31 is cooled by the refrigerant flowing through the core cooling channel R10 via the peripheral wall 27.

[0101] Next, the refrigerant flows from the core cooling channel R10 through each third communication hole R3 into each second coil cooling channel R30. The coils 32 are cooled by the refrigerant flowing through each second coil cooling channel R30. In the second embodiment, the second coil ends 35b of the multiple coils 32 arranged circumferentially around the stator core 31 are individually cooled by the refrigerant flowing through the second coil cooling channels R30 located at their corresponding positions. The refrigerant then flows out from each second coil cooling channel R30 through each fourth communication hole R4 into the external refrigerant channel 100.

[0102] [Effects of the second embodiment] In the second embodiment, in addition to the effects (1-1) to (1-6) of the first embodiment, the following effects can be obtained.

[0103] (2-1) Each first coil cooling channel R20 extends linearly within the first molded portion 41 in a direction inclined with respect to both the axial and radial directions of the stator core 31. Similarly, each second coil cooling channel R30 extends linearly within the second molded portion 42 in a direction inclined with respect to both the axial and radial directions of the stator core 31. In this case, the resin molded portion 40 can be molded in one piece without having to divide it into multiple resin members as in the first embodiment.

[0104] [Example of changes] The above embodiment can be implemented with the following modifications. The above embodiment and the following modifications can be combined with each other to the extent that they do not contradict each other technically.

[0105] ○ In the second embodiment, the number of first coil cooling channels R20 does not have to be the same as the number of coils 32. For example, one first coil cooling channel R20 may be a channel that cools the first coil ends 35a of two coils 32. In this case, the number of first coil cooling channels R20 may be half the number of coils 32.

[0106] Similarly, the number of second coil cooling channels R30 does not have to be the same as the number of coils 32. For example, one second coil cooling channel R30 may be a channel that cools the second coil ends 35b of two coils 32. In this case, the number of second coil cooling channels R30 can be half the number of coils 32. Note that the number of first coil cooling channels R20 and the number of second coil cooling channels R30 do not have to be the same.

[0107] ○ The first communication hole R1 may be a through hole penetrating the peripheral wall 27, as long as it connects the external refrigerant flow path 100 and the first coil cooling flow path R20. In this case, one end R1a of the first communication hole R1 opens on the inner peripheral surface 27a of the peripheral wall 27, which is the inner surface of the housing 11. The first end R20a of the first coil cooling flow path R20 opens on the first outer peripheral surface 41b, which is the outer surface of the first molded portion 41. The first end R20a of the first coil cooling flow path R20 is connected to one end R1a of the first communication hole R1 at the first outer peripheral surface 41b of the first molded portion 41, which abuts against the inner peripheral surface 27a of the peripheral wall 27. The first end surface 41a of the first molded portion 41 does not have to abut against the inner surface 26a of the bottom wall 26.

[0108] ○ The fourth communication hole R4 may be a through hole penetrating the peripheral wall 27, as long as it connects the second coil cooling passage R30 with the external refrigerant passage 100. In this case, one end R4a of the fourth communication hole R4 opens on the inner peripheral surface 27a of the peripheral wall 27, which is the inner surface of the housing 11. The first end R30a of the second coil cooling passage R30 opens on the second peripheral surface 42b, which is the outer surface of the second molded portion 42. The first end R30a of the second coil cooling passage R30 is connected to one end R4a of the fourth communication hole R4 at the second peripheral surface 42b of the second molded portion 42, which abuts against the inner peripheral surface 27a of the peripheral wall 27. The second end surface 42a of the second molded portion 42 does not have to abut against the inner surface 22a of the cover 22.

[0109] ○ The other end R1b of the first communication hole R1 may be connected to the second refrigerant flow path 102, and the other end R4b of the fourth communication hole R4 may be connected to the first refrigerant flow path 101. That is, the first communication hole R1 may be a discharge section for discharging refrigerant from the stator cooling flow path R to the external refrigerant flow path 100, and the fourth communication hole R4 may be an introduction section for introducing refrigerant from the external refrigerant flow path 100 to the stator cooling flow path R. In this case, the refrigerant flows through the stator cooling flow path R in the reverse order of the above embodiment. That is, the refrigerant flows in the order of fourth communication hole R4, second coil cooling flow path R30, third communication hole R3, core cooling flow path R10, second communication hole R2, first coil cooling flow path R20, and first communication hole R1.

[0110] ○ As shown in Figure 9, the stator cooling channel R may have a fifth communication hole R5 instead of the second coil cooling channel R30, the third communication hole R3, and the fourth communication hole R4. The fifth communication hole R5 penetrates radially through the second end 23b of the first channel forming member 23. The fifth communication hole R5 directly connects the core cooling channel R10 and the external refrigerant channel 100. Therefore, the "fifth communication hole R5" corresponds to the "third communication hole that connects the core cooling channel and the external refrigerant channel" in the claim. The fifth communication hole R5 is provided, for example, in the circumferential direction of the stator core 31 at a position corresponding to the second communication hole R2.

[0111] For example, the first connecting hole R1 is the inlet. The fifth connecting hole R5 is the outlet. In this case, the refrigerant flows in the following order: first connecting hole R1, first coil cooling channel R20, second connecting hole R2, core cooling channel R10, and fifth connecting hole R5. The second coil end 35b is cooled via the main section 36 as the first coil end 35a is cooled.

[0112] With this configuration, the motor 10 can be simplified compared to the case where a second coil cooling channel R30 is formed in the second molded portion 42 and a third communication hole R3 and a fourth communication hole R4 are formed in the housing 11. In addition, since the refrigerant flows through the first coil cooling channel R20 before the core cooling channel R10, the same effects as those of the first embodiment (1-2) can be obtained.

[0113] The first connecting hole R1 may be a discharge section, and the fifth connecting hole R5 may be an inlet section. In this case, the refrigerant flows in the following order: fifth connecting hole R5, core cooling channel R10, second connecting hole R2, first coil cooling channel R20, and first connecting hole R1.

[0114] The fifth communication hole R5 does not have to be located in a position corresponding to the second communication hole R2 in the circumferential direction of the stator core 31. For example, the fifth communication hole R5 may be located at a position shifted 180 degrees relative to the second communication hole R2 in the circumferential direction of the stator core 31.

[0115] ○ The stator cooling channel R may have a fifth communication hole R5 in addition to the core cooling channel R10, the first coil cooling channel R20, the second coil cooling channel R30, and the first to fourth communication holes R1 to R4. The fifth communication hole R5 connects the core cooling channel R10 and the external refrigerant channel 100 by, for example, passing radially through the axial central portion of the first channel forming member 23. Therefore, the "fifth communication hole R5" corresponds to the "third communication hole that connects the core cooling channel and the external refrigerant channel" in the claim.

[0116] For example, the first communication hole R1 and the fourth communication hole R4 are inlet sections. The fifth communication hole R5 is a discharge section. In this case, the refrigerant flows in the order of first communication hole R1, first coil cooling channel R20, second communication hole R2, and core cooling channel R10. Alternatively, the refrigerant flows in the order of fourth communication hole R4, second coil cooling channel R30, third communication hole R3, and core cooling channel R10. After the refrigerant merges in the core cooling channel R10, it is discharged from the fifth communication hole R5 to the external refrigerant channel 100. In this case, since the refrigerant flows through the first coil cooling channel R20 and the second coil cooling channel R30 before the core cooling channel R10, the same effects as those of the first embodiment (1-2) can be obtained.

[0117] The first and fourth connecting holes R1 and R4 may serve as discharge points, while the fifth connecting hole R5 may serve as an inlet. In this case, the refrigerant flows from the external refrigerant flow path 100 through the fifth connecting hole R5 into the core cooling flow path R10. The refrigerant that flows into the core cooling flow path R10 is divided into two parts: one that flows into the first coil cooling flow path R20 through the second connecting hole R2, and the other that flows into the second coil cooling flow path R30 through the third connecting hole R3. The refrigerant that flows into the first coil cooling flow path R20 is then discharged to the external refrigerant flow path 100 through the first connecting hole R1. The refrigerant that flows into the second coil cooling flow path R30 is then discharged to the external refrigerant flow path 100 through the fourth connecting hole R4.

[0118] ○ The core cooling channel R10 may be formed inside the peripheral wall 27. In this case, the first to third channel forming members 23 to 25 become unnecessary. ○ The core cooling channel R10 may be formed by a cylindrical member provided inside the peripheral wall 27. For example, the cylindrical member may be a metal pipe.

[0119] ○ Fins may be provided within the core cooling channel R10, protruding from the outer surface of the peripheral wall 27 or the inner surface of the first channel forming member 23. In this case, the surface area of ​​the core cooling channel R10 is increased, thereby increasing the cooling effect of the stator core 31.

[0120] ○ The core cooling channel R10 may be provided with guide walls that guide the flow of refrigerant in the core cooling channel R10 to a desired flow. For example, the core cooling channel R10 may be provided with spiral guide walls that guide the refrigerant to flow spirally through the core cooling channel R10.

[0121] ○ A portion of the first coil end 35a does not need to be exposed within the first coil cooling channel R20. In this case, the first coil end 35a is cooled via the first molded portion 41 by the coolant flowing through the first coil cooling channel R20.

[0122] ○ A portion of the second coil end 35b does not need to be exposed within the second coil cooling channel R30. In this case, the second coil end 35b is cooled via the second molded portion 42 by the coolant flowing through the second coil cooling channel R30.

[0123] ○ The configuration of the housing 11 in the above embodiment is an example. The housing 11 may be composed of, for example, a cylindrical member, a first end wall that closes one opening of the cylindrical member, and a second end wall that closes the other opening of the cylindrical member. In this case, the inner circumferential surface of the cylindrical member, the inner surface of the first end wall, and the inner surface of the second end wall are the inner surfaces of the housing 11. The inside of the housing 11 is partitioned by the inner circumferential surface of the cylindrical member, the inner surface of the first end wall, and the inner surface of the second end wall.

[0124] ○ The configuration of the rotor 50 in the above embodiment is just one example. The rotor 50 may, for example, have a cylindrical rotor core through which a single rotating shaft 13 is inserted, and permanent magnets embedded in the rotor core.

[0125] [Note] The technical concepts that can be understood from each of the above embodiments and their modifications are described below. [1] A motor comprising a motor section and a housing housing the motor section, wherein the motor section comprises a rotor, a stator having a cylindrical stator core and coils wound around the stator core, and a resin molded section for molding the coils with resin, the coils having a first coil end located on a first end face which is one end face in the axial direction of the stator core, and a second coil end located on a second end face which is the other end face in the axial direction of the stator core, the resin molded section having a first molded section for molding the first coil end and a second molded section for molding the second coil end, and a stator cooling passage is provided through which a coolant flows to cool the stator, the stator cooling passage is provided in the housing and comprises a core cooling passage for cooling the stator core and a second molded section provided in the first molded section for cooling the first coil end A motor comprising: a coil cooling channel; a first communication hole provided in the housing that connects an external refrigerant channel with the first coil cooling channel; a second communication hole provided in the housing that connects the first coil cooling channel with the core cooling channel; and a third communication hole provided in the housing that connects the core cooling channel with the external refrigerant channel, wherein one end of the first communication hole and one end of the second communication hole are open on the inner surface of the housing; the first coil cooling channel is a through hole penetrating the first molded portion; the outer surface of the first molded portion is in contact with the inner surface of the housing; the first end of the first coil cooling channel is connected to one end of the first communication hole on the outer surface of the first molded portion that is in contact with the inner surface of the housing; and the second end of the first coil cooling channel, which is the end opposite to the first end, is connected to one end of the second communication hole.

[0126] [2] The motor according to [1], wherein the first communication hole is an introduction section for introducing the refrigerant from the external refrigerant flow path to the stator cooling flow path, and the refrigerant flows in the order of the first communication hole, the first coil cooling flow path, the second communication hole, and the core cooling flow path.

[0127] [3] The stator cooling passage further comprises a second coil cooling passage provided in the second mold portion for cooling the second coil end, and a fourth communication hole provided in the housing for connecting the second coil cooling passage and the external refrigerant passage, wherein the third communication hole connects the core cooling passage and the external refrigerant passage via the second coil cooling passage and the fourth communication hole, one end of the third communication hole and one end of the fourth communication hole are open on the inner surface of the housing, the second coil cooling passage is a through hole penetrating the second mold portion, the outer surface of the second mold portion is in contact with the inner surface of the housing, the first end of the second coil cooling passage is connected to one end of the third communication hole on the outer surface of the second mold portion in contact with the inner surface of the housing, and the second end, which is the end opposite to the first end of the second coil cooling passage, is connected to one end of the fourth communication hole, as described in [1] or [2].

[0128] [4] A motor according to any one of [1] to [3], wherein a portion of the first coil end is exposed in the first coil cooling channel. [5] The motor according to any one of [1] to [4], wherein the first coil cooling channel is circumferential to the stator core within the first mold portion. [Explanation of Symbols]

[0129] 10…Motor, 11…Housing, 12…Motor section, 22a…Inner surface of the cover as the inner surface of the housing, 26a…Inner surface of the bottom wall as the inner surface of the housing, 27a…Inner circumferential surface of the peripheral wall as the inner surface of the housing, 30…Stator, 31…Stator core, 31a…First end face, 31b…Second end face, 32…Coil, 35a…First coil end, 35b…Second coil end, 40…Resin molded section, 41…First molded section, 41a…First end face as the outer surface of the first molded section, 41b…First outer circumferential surface as the outer surface of the first molded section, 42…Second molded section, 42a ...the second end surface as the outer surface of the second molded part, 42b...the second outer peripheral surface as the outer surface of the second molded part, 50...the rotor, 100...the external coolant flow path, R...the stator cooling flow path, R1...the first communication hole, R1a...one end of the first communication hole, R2...the second communication hole, R2a...one end of the second communication hole, R3...the third communication hole, R3a...one end of the third communication hole, R4...the fourth communication hole, R4a...one end of the fourth communication hole, R10...the core cooling flow path, R20...the first coil cooling flow path, R20a...the first end, R20b...the second end, R30...the second coil cooling flow path, R30a...the first end, R30b...the second end.

Claims

1. It comprises a motor unit and a housing that accommodates the motor unit, The motor section comprises a rotor, a stator having a cylindrical stator core and coils wound around the stator core, and a resin molded section that molds the coils with resin. The coil has a first coil end located on a first end face, which is one end face in the axial direction of the stator core, and a second coil end located on a second end face, which is the other end face in the axial direction of the stator core. The resin molded portion comprises a first molded portion for molding the first coil end and a second molded portion for molding the second coil end. A motor is provided with a stator cooling channel through which a refrigerant flows to cool the stator, The stator cooling channel is, The housing is provided with a core cooling channel for cooling the stator core, A first coil cooling channel is provided in the first mold portion for cooling the first coil end, The housing is provided with a first communication hole that connects the external refrigerant flow path and the first coil cooling flow path, A second communication hole is provided in the housing, which connects the first coil cooling channel and the core cooling channel, A third communication hole is provided in the housing, which connects the core cooling channel and the external refrigerant channel, It has, One end of the first communication hole and one end of the second communication hole are open on the inner surface of the housing. The first coil cooling channel is a through-hole that penetrates the first mold portion, The motor is characterized in that the outer surface of the first molded portion is in contact with the inner surface of the housing, and on the outer surface of the first molded portion that is in contact with the inner surface of the housing, the first end of the first coil cooling channel is connected to one end of the first communication hole, and the second end, which is the end of the first coil cooling channel opposite to the first end, is connected to one end of the second communication hole.

2. The first communication hole is an introduction section for introducing the refrigerant from the external refrigerant flow path to the stator cooling flow path, The motor according to claim 1, wherein the refrigerant flows in the order of the first communication hole, the first coil cooling channel, the second communication hole, and the core cooling channel.

3. The stator cooling channel is, A second coil cooling channel is provided in the second mold portion for cooling the second coil end, A fourth communication hole is provided in the housing, which connects the second coil cooling channel and the external refrigerant channel, It further possesses, The third communication hole connects the core cooling channel and the external refrigerant channel via the second coil cooling channel and the fourth communication hole. One end of the third communication hole and one end of the fourth communication hole are open on the inner surface of the housing. The second coil cooling channel is a through-hole that penetrates the second mold portion, The motor according to claim 1, wherein the outer surface of the second mold portion is in contact with the inner surface of the housing, and on the outer surface of the second mold portion in contact with the inner surface of the housing, the first end of the second coil cooling channel is connected to one end of the third communication hole, and the second end, which is the end opposite to the first end of the second coil cooling channel, is connected to one end of the fourth communication hole.

4. The motor according to claim 1, wherein a portion of the first coil end is exposed within the first coil cooling channel.

5. The motor according to claim 1, wherein the first coil cooling channel is circumferentially routed within the first mold portion in the circumferential direction of the stator core.

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