Electric motor

Abstract

To provide a motor in which both a rotor core and a coil end can be efficiently cooled.SOLUTION: An electric motor disclosed herein includes a rotor core that is fixed to a shaft, a stator, and first and second refrigerant flow channels. The stator is disposed radially outward from the rotor core, and coil ends are disposed on both ends of the stator. The first refrigerant flow channel is disposed inside the shaft, and is disposed axially outward from the rotor core. The second refrigerant flow channel extends inside the rotor core. A first outlet of the first refrigerant flow channel is disposed in the shaft, and a refrigerant eject direction in the first outlet is directed toward the coil end. The rotor core is cooled by a refrigerant flowing through the second refrigerant flow channel. The coil ends are cooled by a refrigerant flowing through the first refrigerant flow channel, that is, a refrigerant that is not cooling the rotor.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The technology disclosed in this specification relates to an electric motor.

Background Art

[0002] An electric motor includes a stator and a rotor that rotates inside the stator. Hereinafter, for simplicity of explanation, "electric motor" is simply referred to as "motor". The motor (electric motor) also has a cooling structure for cooling the stator and the rotor. Coil ends are located at both ends of the stator. The coil ends tend to get hot. It is desirable that the cooling structure of the motor can effectively cool the coil ends.

[0003] Patent Document 1 discloses a motor configured to supply a refrigerant inside the shaft of the rotor. A refrigerant outlet is provided on the side surface of the shaft. The refrigerant outlet faces the coil end of the stator. The refrigerant ejected from the refrigerant outlet hits the coil end and cools the coil end.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Although the coil ends tend to get hot, the rotor core also gets hot. This specification provides a motor capable of efficiently cooling both the rotor core and the coil ends.

Means for Solving the Problems

[0006] The motor disclosed herein comprises a shaft, a rotor core, a stator, and first / second refrigerant passages. The shaft is rotatably supported in a housing. The rotor core is fixed to the shaft. The stator is located radially outside the rotor core and has coil ends at both ends. The first refrigerant passage is located inside the shaft. The first refrigerant passage is located outside the rotor core in the axial direction of the shaft. The first refrigerant passage does not pass inside the rotor core. The shaft comprises a large-diameter section and a small-diameter section having a shorter diameter than the large-diameter section, which is located on both sides of the large-diameter section in the axial direction of the shaft. First refrigerant flow path Furthermore, the outlet of the first refrigerant flow path (first outlet) is located in a small diameter section, and the refrigerant ejection direction at the first outlet is directed toward the coil end. The second refrigerant flow path and its outlet (second outlet) are located in a large diameter section, and the refrigerant ejection direction at the second outlet intersects with the refrigerant ejection direction at the first outlet.

[0007] In the motor disclosed herein, the coil ends are cooled by a refrigerant exiting from a first outlet. Since the first refrigerant passage does not pass through the rotor core, the refrigerant in the first refrigerant passage is not heated by the rotor core. The rotor core is cooled by the refrigerant flowing through a second refrigerant passage. In the motor disclosed herein, both the rotor core and the coil ends are cooled by a cold refrigerant. This motor can efficiently cool both the rotor core and the coil ends.

[0008] The The refrigerant exiting from outlet 2 collides with the refrigerant exiting from outlet 1 and is scattered towards the coil end. The coil end is cooled not only by the refrigerant exiting from the first refrigerant passage but also by the refrigerant exiting from the second refrigerant passage. 。

[0014] Details of the technology disclosed herein and further improvements are described in the following "Modes for Carrying Out the Invention". [Brief explanation of the drawing]

[0015] [Figure 1] This is a cross-sectional view of the motor according to the first embodiment. [Figure 2] Figure 1 shows the motor viewed from the direction of the dashed arrow II. [Figure 3] This is a cross-sectional view of a modified example of the motor of the first embodiment. [Figure 4] This is a cross-sectional view of the motor in the first reference example. [Figure 5]Figure 4 shows the motor viewed from the direction of the dashed arrow V. [Figure 6] This is a view of the motor in the second reference example, seen from the direction of the dashed arrow V in Figure 4. [Modes for carrying out the invention]

[0016] (First Embodiment) Motor 2 of the first embodiment will be described with reference to the drawings. Figure 1 shows a cross-sectional view of motor 2. Motor 2 comprises a stator 10 and a rotor 20. The rotor 20 comprises a shaft 21 and a rotor core 22. For convenience of explanation, the axial direction of the shaft 21 will be referred to as the shaft axis direction below. The X direction in the coordinate system of Figure 1 corresponds to the shaft axis direction.

[0017] The stator 10 is fixed inside the motor housing (housing 3). The stator 10 comprises a stator core 11 and coil ends 12a and 12b. The stator core 11 is made by laminating multiple electromagnetic steel sheets. The stator core 11 may also be made by compressing magnetic iron powder under pressure. A winding (not shown) is wound around the stator core 11. The winding forms a coil. The coil ends 12a and 12b refer to the ends of the coil wound around the teeth of the stator core 11 in the direction of the shaft axis. In other words, the coil ends 12a and 12b refer to the coil portions that protrude from the end face of the stator core 11 in the direction of the shaft axis. Note that in the figure, the stator core 11 is drawn in a simplified manner, and the details of the structure of the stator 10 (such as the shape of the teeth) are not shown. The stator 10 is a cylinder extending in the direction of the shaft axis. The coil ends 12a and 12b are located at both ends of the stator 10 in the direction of the shaft axis. As shown in Figure 2, the coil end 12a includes multiple coil ends, and these multiple coil ends 12a are arranged at equal intervals along the circumferential direction of the stator 10.

[0018] The shaft 21 of the rotor 20 is rotatably supported inside the housing 3 via a bearing. One end of the shaft 21 extends outside the housing 3. The space between the opening in the housing 3 and the shaft 21 is sealed by a mechanical seal 25.

[0019] The rotor core 22 is fixed to the shaft 21. Both ends of the rotor core 22 are fixed to the shaft 21 by end plates (not shown). The rotor core 22 is located inside the cylindrical stator 10. In other words, the stator 10 surrounds the rotor core 22. In yet another word, the stator 10 is located radially outside the rotor core 22. The rotor core 22 is located between the coil ends 12a and 12b at both ends of the stator 10 in the axial direction of the shaft.

[0020] Refrigerant 9 is stored at the bottom of housing 3, and pump 4 pumps the refrigerant 9 from the bottom and supplies it to the inside of shaft 21. Refrigerant 9 is oil and also acts as a lubricant to ensure the smooth rotation of rotor 20. In Figure 1, pump 4 is located outside housing 3, but pump 4 may also be located inside housing 3.

[0021] A refrigerant flow path 5 extends from the pump 4 to the end of the shaft 21. A common refrigerant flow path 30 is formed from the end of the shaft 21 into the interior. Although not shown in the diagram, the tip of the refrigerant flow path 5 and the inlet of the common refrigerant flow path 30 are connected by a rotary fluid coupling. Inside the shaft 21, the common refrigerant flow path 30 is divided into a first refrigerant flow path 31 and a second refrigerant flow path 32. The second refrigerant flow path 32 extends into the interior of the rotor core 22. The first refrigerant flow path 31 does not extend to the inside of the rotor core 22, but is located outside the rotor core 22 in the direction of the shaft axis. In other words, the first refrigerant flow path 31 does not pass inside the rotor core 22. The refrigerant supplied by the pump 4 is divided into the first refrigerant flow path 31 and the second refrigerant flow path 32.

[0022] Fig. 2 shows a view of the motor 2 as seen from the direction of the dashed-dotted arrow II in Fig. 1. However, in Fig. 2, only the stator 10 and the rotor 20 are depicted, and the illustration of other components is omitted. The shaft 21 has a plurality of first refrigerant flow paths 31, and each first refrigerant flow path 31 extends in the radial direction of the shaft 21. In other words, the plurality of first refrigerant flow paths 31 extend radially from the center of the shaft 21. Each first refrigerant flow path 31 opens to the side surface of the shaft 21. The opening of the first refrigerant flow path 31 is referred to as the first outlet 31a. The first outlet 31a opens toward the coil end 12a.

[0023] The refrigerant passing through the first refrigerant flow path 31 jets out from the first outlet 31a toward the coil end 12a. The thick arrow line A in Figs. 1 and 2 represents the jetting direction of the refrigerant exiting from the first outlet 31a. The refrigerant jetting direction at the first outlet 31a faces the coil end 12a. In other words, the refrigerant jetting direction at the first outlet 31a extends toward the coil end 12a.

[0024] As shown in Fig. 2, a plurality of coil ends 12a are arranged so as to surround the rotor 20. When the rotor 20 rotates, the plurality of first outlets 31a also rotate, and refrigerant is jetted onto all of the plurality of coil ends 12a. The coil end 12a is cooled by the jetted refrigerant.

[0025] The second refrigerant flow path 32 passes through the inside of the rotor core 22. The rotor core 22 is cooled by the refrigerant flowing through the second refrigerant flow path 32. On the other hand, the first refrigerant flow path 31 does not pass through the inside of the rotor core 22. The refrigerant passing through the first refrigerant flow path 31 jets out from the first outlet 31a toward the coil end 12a. The coil end 12a is cooled by the cold refrigerant that does not pass through the inside of the rotor core 22. In the motor 2 of the embodiment, each of the rotor core 22 and the coil end 12a is cooled by cold refrigerant. The motor 2 can efficiently cool both the rotor core 22 and the coil end 12a. Incidentally, the other coil end 12b is cooled by the refrigerant that has passed through the inside of the rotor core 22, as will be described next.

[0026] The second refrigerant flow path 32 extends into the interior of the rotor core 22. The second refrigerant flow path 32 is inside the rotor core 22 and also passes through the interior of the shaft 21. In the direction of the shaft axis, the central part of the shaft 21 has a larger diameter than the ends. The central part with a larger diameter is referred to as the large-diameter section 21a. The smaller-diameter sections extending outward from both ends of the large-diameter section 21a are referred to as the small-diameter sections 21b. The rotor core 22 is fixed to the large-diameter section 21a. There is a step at the boundary between the large-diameter section 21a and the small-diameter section 21b, and a part of the end face 24 of the large-diameter section 21a is exposed. The second refrigerant flow path 32 opens at the end faces 24 at both ends of the large-diameter section 21a. The openings of the second refrigerant flow path 32 are referred to as the second outlets 32a and 32b. Of the two end faces of the rotor core 22, the end face closer to the first refrigerant flow path 31 is called the proximal end face 22a of the rotor core 22, and the end face further away from the first refrigerant flow path 31 is called the distal end face 22b. The second outlet 32a is located on the side of the proximal end face 22a. In other words, the second outlet 32a is located on the side closer to the first outlet 31a in the shaft axis direction. The second outlet 32b is located on the side of the distal end face 22b. In other words, the second outlet 32b is located on the opposite side of the rotor core 22 from the first outlet 31a.

[0027] Refrigerant is also ejected from the second outlet 32a, which is located on the side of the proximal end face 22a. The thick arrow line B in Figure 1 indicates the direction of refrigerant ejection from the second outlet 32a. The direction of refrigerant ejection from the second outlet 32a is parallel to the shaft axis direction. The direction of refrigerant ejection at the second outlet 32a intersects with the direction of refrigerant ejection at the first outlet 31a. The direction of refrigerant ejection at the second outlet 32a is not shown in Figure 2. However, in Figure 2, the thick arrow line A intersects with the second outlet 32a, so it can be understood that the direction of refrigerant ejection at the second outlet 32a intersects with the direction of refrigerant ejection at the first outlet 31a.

[0028] The refrigerant passing through the second refrigerant flow path 32 cools the rotor core 22, causing its temperature to rise slightly. The rotor 20 is rotating. The refrigerant ejected from the second outlet 32a collides with the refrigerant ejected from the first outlet 31a and is scattered toward the coil end 12a by centrifugal force. The coil end 12a is cooled primarily by the refrigerant exiting from the first outlet 31a, but the refrigerant exiting from the second outlet 32a also contributes to the cooling of the coil end 12a.

[0029] Coolant is also ejected from the second outlet 32b located on the distal end face 22b. The rotor 20 is rotating. The coolant exiting from the second outlet 32b is bent towards the coil end 12b by centrifugal force. The thick arrow C in Figure 1 indicates the direction of the coolant exiting from the second outlet 32b. The coolant exiting from the second outlet 32b cools the coil end 12b.

[0030] The rotor core 22 has multiple second outlets 32a (multiple second outlets 32b), and these multiple second outlets 32a (multiple second outlets 32b) are arranged at equal intervals along the circumferential direction of the rotor core 22.

[0031] (Modified Version) Figure 3 shows a cross-sectional view of a modified version of motor 2 (motor 102). In motor 102, the first refrigerant flow path 131 is provided on both sides of the rotor core 22 in the direction of the shaft axis. Furthermore, the angle of the first refrigerant flow path 131 is different from that of motor 2 in the first embodiment. In motor 2 in the first embodiment, the longitudinal direction of the first refrigerant flow path 31 was perpendicular to the direction of the shaft axis. In motor 102, the longitudinal direction of the first refrigerant flow path 131 is not perpendicular to the direction of the shaft axis. However, the longitudinal direction of the first refrigerant flow path 131 extends toward the coil end 12a. The first outlet 131a also faces toward the coil end 12a. The direction of refrigerant ejection from the first outlet 131a (thick arrow line A) is toward the coil end 12a. In other words, the direction of refrigerant ejection at the first outlet 131a extends toward the coil end 12a. Furthermore, the refrigerant ejection direction of the second outlet 32a (thick arrow line B) intersects with the refrigerant ejection direction of the first outlet 131a (thick arrow line A). Motor 102 has the same effect as motor 2.

[0032] On the opposite side of the rotor core 22, the longitudinal direction of the first refrigerant flow path 131 extends toward the coil end 12b. The first outlet 131b also faces toward the coil end 12b. The direction of refrigerant ejection from the first outlet 131b (thick arrow line C) is toward the coil end 12b. In other words, the direction of refrigerant ejection at the first outlet 131b (thick arrow line C) extends toward the coil end 12b. Furthermore, the direction of refrigerant ejection at the second outlet 32b (thick arrow line D) intersects with the direction of refrigerant ejection at the first outlet 131b (thick arrow line C). The refrigerant ejected from the second outlet 32b collides with the refrigerant ejected from the first outlet 131b and is scattered toward the coil end 12b. The coil end 12b is cooled by the refrigerant ejected from the first outlet 131b and the refrigerant ejected from the second outlet 32b. In the modified motor 102, the coil ends 12a and 12b at both ends of the stator 10 are effectively cooled.

[0033] ( First reference example (Refer to Figures 4 and 5) First reference example The motor 202 is described below. Figure 4 is a cross-sectional view of the motor 202, and Figure 5 is a view of the motor 202 from the direction of the dashed arrow V in Figure 4. However, in Figure 5 as well, only the stator 10 and rotor 220 of the motor 202 are depicted, and the other parts are not shown.

[0034] The motor 202 comprises a stator 10 and a rotor 220, the rotor 220 comprising a shaft 221 and a rotor core 22.

[0035] In the motor 202, multiple protrusions 226 extend from the side of the shaft 221 toward the coil end 12a. A common refrigerant passage 30 extends along the centerline of the shaft 221. The first refrigerant passage 231 extends radially from the common refrigerant passage 30 toward the shaft 221. The first refrigerant passage 231 further extends into the interior of the protrusions 226. The outlet of the first refrigerant passage 231 (first outlet 231a) opens at the tip of the protrusion 226.

[0036] As shown in Figure 5, multiple first refrigerant flow paths 231 extend radially from the center of the shaft 221. Each first refrigerant flow path 231 opens at the tip of the projection 226. The opening of the first refrigerant flow path 231 is referred to as the first outlet 231a. The first refrigerant flow path 231 extends toward the coil end 12a, and the first outlet 231a opens toward the coil end 12a. The direction of refrigerant ejection at the first outlet 231a is toward the coil end 12a. In other words, the direction of refrigerant ejection at the first outlet 231a extends toward the coil end 12a.

[0037] Similar to motor 2 in the first embodiment, in motor 202, the refrigerant that has passed through the first refrigerant flow path 231 is ejected from the first outlet 231a toward the coil end 12a. The thick arrow A in Figure 4 indicates the direction of refrigerant ejection from the first outlet 231a. The first refrigerant flow path 231 is cold because it does not pass inside the rotor core 22. The coil end 12a is cooled by the cold refrigerant that has not passed through the rotor core 22. Furthermore, the first outlet 231a is closer to the coil end 12a compared to the case of the first embodiment. The position of the first outlet 231a close to the coil end 12a also contributes to the effective cooling of the coil end 12a.

[0038] The second refrigerant flow path 232 passes through the interior of the rotor core 22. The rotor core 22 is cooled by the refrigerant flowing through the second refrigerant flow path 232. The second refrigerant flow path 232 is inside the rotor core 22 and passes outside the shaft 221. The second refrigerant flow path 232 opens at the proximal end face 22a and the distal end face 22b of the rotor core 22 (second outlets 232a and 232b). The thick arrow line B indicates the refrigerant ejection direction of the second outlet 232a, which is located on the proximal end face 22a. The refrigerant ejection direction of the second outlet 232a (thick arrow line B) intersects with the projection 226. Although the refrigerant ejection direction is not shown in Figure 5, the projection 226 and the second outlet 232a overlap when viewed from the shaft axis direction, so it can be understood that the refrigerant ejection direction of the second outlet 232a overlaps with the projection 226.

[0039] The refrigerant passing through the second refrigerant flow path 232 cools the rotor core 22, causing its temperature to rise slightly. The rotor 220 rotates. The refrigerant ejected from the second outlet 232a collides with the projection 226 and is scattered toward the coil end 12a by centrifugal force. The coil end 12a is cooled primarily by the refrigerant ejected from the first outlet 231a, but the refrigerant ejected from the second outlet 232a also contributes to the cooling of the coil end 12a. In particular, the projection 226 acts as a guide, directing the flow of refrigerant ejected from the second outlet 232a toward the coil end 12a.

[0040] Coolant is also ejected from the second outlet 232b located on the distal end face 22b. The rotor 220 is rotating. The coolant exiting from the second outlet 232b is bent towards the coil end 12b by centrifugal force. The thick arrow C in Figure 4 indicates the direction of the coolant exiting from the second outlet 232b. The coolant exiting from the second outlet 232b cools the coil end 12b.

[0041] The rotor core 22 has multiple second outlets 232a (multiple second outlets 232b), and these multiple second outlets 232a (multiple second outlets 232b) are arranged at equal intervals along the circumferential direction of the rotor core 22.

[0042] A first refrigerant flow path and a projection may also be provided on the distal end face 22b. On the distal end face 22b, the outlet of the first refrigerant flow path (first outlet) is also provided at the tip of the projection. On the distal end face 22b, the refrigerant ejection direction at the second outlet 2321b intersects with the projection.

[0043] ( Second reference example (Refer to Figure 6) Second reference example The motor 302 is described below. The cross-sectional view of the motor 302 is the same as in Figure 4. However, the projection 226 is replaced by a disc 326. Figure 6 is a view of the motor 302 from the direction of the dashed arrow V in Figure 4. However, in Figure 6 as well, only the stator 10 and rotor 320 of the motor 302 are depicted, and the other parts are omitted from the illustration. did.

[0044] The motor 302 comprises a stator 10 and a rotor 320. The rotor 320 comprises a shaft 321 and a rotor core 22.

[0045] In the motor 302, a disc 326 is attached coaxially to the shaft 321. The disc 326 is positioned in the same location as the coil end 12a in the axial direction of the shaft. A common refrigerant passage 30 extends along the centerline of the shaft 321. The first refrigerant passage 331 extends radially from the common refrigerant passage 30 along the shaft 321. The first refrigerant passage 331 further extends into the interior of the disc 326. The outlet of the first refrigerant passage 331 (first outlet 331a) opens onto the side (circumferential surface) of the disc 326. The refrigerant ejection direction of the first outlet 331a is directed toward the coil end 12a.

[0046] As shown in Figure 6, multiple first refrigerant flow paths 331 extend radially from the center of the shaft 321. Each first refrigerant flow path 331 opens onto the side of the disc 326. The opening of the first refrigerant flow path 331 is referred to as the first outlet 331a. The first refrigerant flow paths 331 extend toward the coil end 12a, and the first outlet 331a opens toward the coil end 12a.

[0047] Similar to motor 2 in the first embodiment, in motor 302, the refrigerant that has passed through the first refrigerant passage 331 is ejected from the first outlet 331a toward the coil end 12a. The first refrigerant passage 331 is cold because it does not pass inside the rotor core 22. The coil end 12a is cooled by the cold refrigerant that has not passed through the rotor core 22. Furthermore, the first outlet 331a is closer to the coil end 12a compared to the case of the first embodiment. The position of the first outlet 331a close to the coil end 12a also contributes to the effective cooling of the coil end 12a.

[0048] The second refrigerant passage of motor 302 is the same as the second refrigerant passage 232 of motor 202. The second refrigerant passage 232 passes inside the rotor core 22. The rotor core 22 is cooled by the refrigerant flowing through the second refrigerant passage 232. The second refrigerant passage 232 is inside the rotor core 22 and passes outside the shaft 221.

[0049] In the motor 302, the second refrigerant flow path 232 opens to the proximal end face 22a and the distal end face 22b of the rotor core 22. The refrigerant outlet provided on the proximal end face 22a corresponds to the second outlet 332a. The second refrigerant flow path extends in the direction of the shaft axis inside the rotor core 22 and opens at the end face of the rotor core 22 (second outlet 332a). Although the direction of refrigerant ejection is not shown in Figure 6, the disc 326 and the second outlet 332a overlap when viewed from the direction of the shaft axis, so it can be understood that the direction of refrigerant ejection from the second outlet 332a coincides with that of the disc 326.

[0050] The refrigerant passing through the second refrigerant flow path 232 cools the rotor core 22, causing its temperature to rise slightly. The rotor 320 rotates. The refrigerant ejected from the second outlet 332a collides with the disc 326 and is scattered toward the coil end 12a by centrifugal force. The coil end 12a is cooled primarily by the refrigerant ejected from the first outlet 331a, but the refrigerant ejected from the second outlet 332a also contributes to the cooling of the coil end 12a. In particular, the disc 326 acts as a guide, directing the flow of refrigerant ejected from the second outlet 332a toward the coil end 12a.

[0051] Although not shown in the diagram, the motor 302 also has a second outlet (another refrigerant outlet of the second refrigerant flow path) at the distal end face of the rotor core 22. The refrigerant exiting from the second outlet at the distal end face cools the coil end 12b.

[0052] A first refrigerant flow path and a disc may also be provided on the distal end face 22b. On the distal end face 22b, the outlet of the first refrigerant flow path (first outlet) is also provided on the side of the disc. On the distal end face 22b, the refrigerant ejection direction at the second outlet 2321b intersects with the projection.

[0053] As explained above, the motor 2(10 2) This allows for efficient cooling of both the coil end and the rotor core. Additionally, the projection 226 or disc 326 provided on the shaft guides the refrigerant exiting the second outlet 232a (332a) to the coil end 12a. The projection 226 or disc 326 further enhances the efficiency of the coil end cooling.

[0054] Examples and reference examples The following are points to note regarding the technology described above. The second refrigerant passage runs through the inside of the rotor core. The second refrigerant passage may run either through the inside of the shaft or through the outside of the shaft. In other words, "inside the rotor core" in this specification means the inside of the rotor core's outline.

[0055] "The refrigerant outlet (first outlet) of the first refrigerant flow path is open toward the coil end" means that while the shaft is rotating, the first outlet is facing either coil end 12a.

[0056] The second refrigerant passage runs through the interior of the rotor core. In other words, at least a portion of the second refrigerant passage is located between one end face and the other end face of the rotor core in the axial direction of the shaft. In other words, at least a portion of the second refrigerant passage is located in the area where the rotor core and the shaft overlap in the axial direction of the shaft.

[0057] Although specific examples of the present invention have been described in detail above, these are merely illustrative and do not limit the scope of the claims. The technologies described in the claims include various modifications and changes to the specific examples illustrated above. The technical elements described in this specification or drawings exhibit technical usefulness individually or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technologies illustrated in this specification or drawings can achieve multiple objectives simultaneously, and achieving even one of these objectives itself constitutes technical usefulness. [Explanation of symbols]

[0058] 2, 102, 202, 302: Motor 3: Housing 4: Pump 5: Refrigerant passage 10: Stator 11: Stator core 12a, 12b: Coil end 20, 220, 320: Rotor 21, 221, 321: Shaft 21a: Large diameter section 21b: Small diameter section 22: Rotor core 22a: Proximal end face 22b: Distal end face 24: End face 25: Mechanical seal 30: Common refrigerant passage 31, 131, 231, 331: First refrigerant passage 31a, 131a, 231a, 331a: First outlet 32, 232: Second refrigerant passage 32a, 32b, 232a, 232b, 332a: Second outlet 226: Projection 326: Disc

Claims

[Claim 1] A shaft rotatably supported in the housing, The rotor core fixed to the aforementioned shaft, A stator is positioned radially outward from the rotor core and has coil ends at both ends, A first refrigerant flow path provided inside the shaft, the first refrigerant flow path being located outside the rotor core in the axial direction of the shaft, A second refrigerant flow path passing through the inside of the aforementioned shaft, It is equipped with, The shaft comprises a large-diameter portion and a small-diameter portion having a shorter diameter than the large-diameter portion, which is arranged on both sides of the large-diameter portion in the axial direction. The rotor core is fixed to the large diameter portion, The first refrigerant flow path and the first outlet of the first refrigerant flow path are provided in the small diameter portion, and the direction of refrigerant ejection at the first outlet is directed toward the coil end. The second refrigerant flow path and the second outlet of the second refrigerant flow path are provided in the large-diameter portion, and the refrigerant ejection direction at the second outlet intersects with the refrigerant ejection direction at the first outlet. Electric motor.

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