Motor

Abstract

A motor 100 includes a housing 30, a stator 10, and a rotor 20. The stator 10 includes a stator core 1 and a coil. The coil includes a slot line part 2s accommodated in a slot, and coil end parts E1, E2 composed of extension lines 2e extending to the outside of the stator core 1 in the axial direction. The housing 30 has cooling liquid flow passages 6a, 6b1, 6b2 that are formed inside a wall and through a cooling liquid passes, and cooling liquid ports 71, 72 that communicate between the cooling liquid flow passages 6b1, 6b2 and a space inside the housing 30 in which the coil end parts E1, E2 are arranged. The cooling liquid ports 71, 72 are formed to be inclined with respect to a plane perpendicular to the axial direction such that the cooling liquid ports 71, 72 extend inward into the housing 30 toward the inner side in the axial direction.

Description

Motor

[0001] The present invention relates to a motor including a stator, a rotor, and a housing.

[0002] Japanese Patent Laid-Open Publication No. 2015-33226 (Patent Document 1) discloses a motor equipped with a cooling structure capable of circulating a coolant such as oil. This motor includes a rotor, a stator including a core and a coil, and a case that houses these. The case has a first inner wall surface and a second inner wall surface that face each other in the direction of the rotation axis, and an inner circumferential wall surface that surrounds the stator between them. Holes that serve as liquid inlet ports are provided at multiple different positions in the circumferential direction of the first inner wall surface. Holes that serve as liquid outlet ports are provided at multiple different positions in the circumferential direction of the second inner wall surface. A gap is formed between the inner circumferential wall surface of the case and the outer circumferential surface of the stator, allowing the coolant to flow from the first inner wall surface side to the second inner wall surface side.

[0003] JP 2015-33226 A

[0004] The present application discloses a motor having a cooling structure that can efficiently cool a motor with a simple configuration.

[0005] A motor according to an embodiment of the present invention includes a housing, a stator accommodated in the housing, and a rotor disposed inside the stator and rotatably supported by the housing. The stator includes a stator core having a plurality of slots and coils formed by conductive wires inserted into the slots. The coils include slot wire portions housed in the slots and coil end portions formed by extending wires extending from the slots to the outside in the axial direction of the stator core. The housing includes a coolant flow path formed inside a wall constituting the housing for passing a coolant, and a coolant port radially outside the coil end portion, communicating the coolant flow path with a space within the housing in which the coil end portion is disposed. The coolant port is formed at an angle with respect to a plane perpendicular to the axial direction so as to approach the axial inner side as it extends inward of the housing.

[0006] FIG. 1 is a cross-sectional view showing an example of the configuration of a motor according to this embodiment. FIG. 2 is a perspective view of the stator 10 shown in FIG. 1. FIG. 3 is a cross-sectional perspective view of the vicinity of the cover flow paths 6b1 and 6b2 shown in FIG. 1. FIG. 4 is a view of the vicinity of the cover flow path 6b2 in FIGS. 1 and 3 as seen from the axial outside. FIG. 5 is a view showing a modified example of the multiple holes of the coolant port 72 in FIG. 4. FIG. 6 is a diagram for explaining an example of the flow of coolant in the motor 100. FIG. 7 is a diagram for explaining an example of the flow of coolant in the motor 100.

[0007] The inventors have studied a cooling structure for improving the cooling efficiency of a motor. In their study, they focused on the movement of the coolant introduced into the housing. As a result, they found that by preventing the flow of coolant from concentrating near the inlet port into the housing, the circulation of the coolant near the coil end portion can be made more efficient. After extensive study into a configuration for preventing the flow of coolant from concentrating near the inlet port, they found that by tilting the inlet port, the concentration of the flow of coolant near the inlet port can be alleviated. The following embodiment is based on this finding.

[0008] (Configuration 1) A motor according to an embodiment of the present invention includes a housing, a stator accommodated in the housing, and a rotor disposed inside the stator and rotatably supported by the housing. The stator has a stator core with a plurality of slots and coils formed by conductor wires inserted into the slots. The conductor wires of the coils include slot wire portions housed in the slots and coil end portions formed by extending wires from the slots to the outside in the axial direction of the stator core. The housing has a coolant flow path formed inside a wall constituting the housing for passing a coolant, and a coolant port radially outside the coil end portion, communicating the coolant flow path with a space within the housing in which the coil end portion is disposed. The coolant port is formed at an angle with respect to a plane perpendicular to the axial direction so as to approach the axial inner side as it extends inward of the housing.

[0009] According to the above-described configuration 1, the coolant port that guides the coolant from the coolant flow path inside the housing wall to the space in the coil end portion (coil end chamber) inside the housing is inclined axially inward toward the housing, i.e., toward the stator core. As a result, the flow direction of the coolant introduced from the coolant port into the housing has a component that flows axially inward. This makes it less likely that the flow of the coolant introduced from the coolant port will concentrate near the coolant port. This improves the efficiency of the circulation of the coolant near the coil end portion, improving cooling efficiency. As a result, efficient cooling is possible with a simple configuration.

[0010] (Configuration 2) A motor according to an embodiment of the present invention includes a housing, a stator accommodated in the housing, and a rotor disposed inside the stator and rotatably supported by the housing. The stator has a stator core with a plurality of slots and coils formed by conductor wires inserted into the slots. The conductor wires of the coils include slot wire portions housed in the slots and coil end portions formed by extending wires extending from the slots to the outside in the axial direction of the stator core. The housing has a coolant flow path formed inside a wall constituting the housing for passing a coolant, and a coolant port, radially outside the coil end portion, communicating between the coolant flow path and a space within the housing in which the coil end portion is disposed. The coolant port is formed by a plurality of holes extending in directions that move away from each other as they extend inward of the housing.

[0011] According to the above-described configuration 2, the coolant port that guides the coolant from the coolant flow path inside the housing wall to the space in the coil end portion (coil end chamber) inside the housing is formed by multiple holes. The multiple holes are formed extending in directions away from each other toward the inside of the housing. This facilitates dispersion of the coolant introduced into the housing from the multiple holes of the coolant port within the housing. This prevents the flow of coolant introduced from the coolant port from concentrating near the coolant port. This improves the efficiency of circulation of the coolant near the coil end portion, thereby improving cooling efficiency. As a result, efficient cooling is possible with a simple configuration. Note that in configuration 2, the coolant port may be formed at an angle with respect to a plane perpendicular to the axial direction so as to approach the axially inner side as it extends inward of the housing.

[0012] The inside of the housing is the direction from the outside to the inside of the housing, that is, the direction toward the interior of the housing in the thickness direction of the housing wall. The radially outside of the coil end portion is a position radially outward from the coil end portion that overlaps with the coil end portion when viewed from the radial direction. The coolant port radially outside the coil end portion is located in a position where at least a portion of the coolant port overlaps with the coil end portion when viewed from the radial direction. Note that the coolant port may be positioned so that the entire coolant port overlaps with the coil end portion when viewed from the radial direction.

[0013] (Configuration 3) In the above configurations 1 or 2, the housing may have a housing main body that holds the stator core and a cover that covers at least a portion of the radially outer side of the coil end portion. The coolant flow path may be formed across both the housing main body and the cover. The coolant port may be configured to communicate between a cover flow path formed in the cover, one of the coolant flow paths, and a space in the housing in which the coil end portion is disposed. This allows the coolant that has passed through the flow path in the housing main body that holds the stator core and the flow path in the cover to be introduced into the housing from the coolant port. Therefore, the coolant can be introduced into the housing at a position close to the coil end portion after passing through a flow path located on the outer periphery of the stator core.

[0014] For example, a flow path portion of the coolant flow path in the housing main body (main body flow path) may be formed to extend circumferentially radially outside the stator core. Also, a flow path portion of the coolant flow path in the cover (cover flow path) may be formed to extend axially from a flow path portion of the housing main body. This allows the coolant to flow circumferentially along the outer periphery of the stator core within the wall of the housing main body, and then guide the coolant axially and introduce it into the housing near the coil end portion.

[0015] (Configuration 4) In the above configuration 3, the housing main body may have an external flow path port that communicates between the coolant flow path and the outside of the housing. The external flow path port and the coolant port may be arranged so that at least a portion of the rotor is located between the external flow path port and the coolant port when viewed in the axial direction. This allows the external flow path port and the coolant port to be positioned at positions that are spaced apart to a certain extent in the circumferential direction. This ensures a certain length of the flow path in the housing main body through which the coolant entering from the external flow path port must travel before reaching the coolant port.

[0016] (Configuration 5) In the above configuration 3 or 4, the cover may include a first cover attached to one axial end of the housing body and a second cover attached to the other axial end of the housing body. The coolant flow path may be formed across the housing body, the first cover, and the second cover. The coolant port may be formed in each of the first cover and the second cover.

[0017] This prevents the flow of coolant from concentrating near the coolant ports in both the space where the coil end portions on one axial side of the stator core are arranged and the space where the coil end portions on the other axial side of the stator core are arranged, improving the efficiency of the circulation of coolant near the coil end portions on both axial ends of the stator core and the cooling efficiency.

[0018] (Configuration 6) In any of the above configurations 1 to 5, the housing may have an interior / exterior communication port that communicates between a space within the housing in which the coil end portion is disposed and the outside of the housing. The interior / exterior communication port and the coolant port may be arranged such that at least a portion of the rotor is located between the interior / exterior communication port and the coolant port when viewed in the axial direction.

[0019] This allows the internal / external communication port and the coolant port to be positioned at a certain distance from each other, so that the coolant introduced through the coolant port comes into contact with most of the coil end portion before being discharged through the internal / external communication port, thereby enhancing the cooling effect of the coolant.

[0020] In the above configuration, the housing may have a coolant accommodating portion that hermetically holds the coolant in a space where the coil end portion is disposed. The housing may have a rotor accommodating portion that accommodates the rotor. The motor may have a cylindrical sealing member that separates the coolant accommodating portion from the rotor accommodating portion and keeps the coolant accommodating portion liquid-tight.

[0021] (Example of Overall Motor Configuration) An example of an embodiment of the present invention will now be described with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of the configuration of a motor 100 according to this embodiment. The motor 100 includes a stator 10 and a rotor 20. The rotor 20 is rotatably supported inside the stator 10. The stator 10 and the rotor 20 are arranged coaxially. The axial direction of the motor 100 is the same as the axial direction of the stator 10 and the axial direction of the rotor 20 (i.e., the direction of the rotation axis J). The stator 10 and the rotor 20 are housed in a housing 30. The stator 10 is fixed relative to the housing 30, and the rotor 20 is rotatably supported relative to the housing 30.

[0022] In the example of FIG. 1 , the housing 30 includes a first cover 31, a second cover 32, and a housing main body 33. The housing main body 33 is formed in a cylindrical shape that surrounds the outer periphery of the stator 10 and supports the outer periphery of the stator 10. The housing main body 33 holds a stator core 1, which will be described later. The first cover 31 is attached to one axial end of the housing main body 33. The first cover 31 covers one axial end of the stator 10 and the rotor 20. The first cover 31 supports the rotor 20 via a bearing 31 a. The second cover 32 is attached to the other axial end of the housing main body 33. The second cover 32 covers the other axial end of the stator 10 and the rotor 20. The second cover 32 supports the rotor 20 via a bearing 32 a. In the example of Figure 1, the first cover 31, the housing main body 33, and the second cover 32 are each formed as separate members (separate bodies), but either the first cover 31 and the housing main body 33, or the second cover 32 and the housing main body 33, may be formed integrally, i.e., as a single member.

[0023] The stator 10 includes a stator core 1 and a conductor 2. The stator core 1 has a plurality of slots arranged in the circumferential direction. The conductor 2 includes a plurality of slot wire portions 2s inserted into each of the plurality of slots, and an extension wire 2e extending from each of the plurality of slot wire portions 2s to the outside of the slot. The extension wire 2e extends axially outward from the stator core 1. The extension wires 2e extending from the plurality of slot wire portions 2s form coil end portions E1, E2. The coil end portions E1, E2 are arranged on both axial sides of the stator core 1.

[0024] N slot wires (N is a natural number) are inserted into each slot, arranged radially in N layers. Three-phase coils, U-phase, V-phase, and W-phase, are formed by the conductor wires 2. Bus bars 5 are connected to the ends of the conductor wires 2 that form the coils of each phase of the stator 10. The bus bars 5 are connected by welding to extension wires 2e that extend from one axial end of the stator core 1. The bus bars 5 are lead wires (power supply wires) for the coils of the stator 10.

[0025] FIG. 2 is a perspective view of the stator 10 shown in FIG. The extension wire 2e forms a coil end portion E1 at one axial end side J1 and a coil end portion E2 at the other axial end side J2. The coil end portions E1 and E2 are formed over the entire circumferential direction at both axial ends of the stator core 1. When viewed from the axial direction, the outer peripheral edges of the coil end portions E1 and E2 are located inside the outer peripheral edge of the stator core 1. In the example of FIG. 2, the bus bar 5, the neutral conductor 4, and the crossover wire 2B are connected by welding to the coil end portion E1 at one axial end side J1. Note that at least one of the bus bar 5, the neutral conductor 4, and the crossover wire 2B may be connected to the coil end portion E2 at the other axial end side J2.

[0026] As shown in FIG. 1 , the first cover 31 covers at least a portion of the radially outer side of the coil end portion E1. That is, the first cover 31 has a portion that overlaps with the coil end portion E1 when viewed radially. The first cover 31 forms at least a portion of the wall of the coil end chamber, i.e., the space in which the coil end portion E1 at one axial end J1 of the housing 30 is disposed. In the example of FIG. 1 , the first cover 31 forms the axially outer and radially outer walls of the coil end chamber. The first cover 31 is assembled to the housing main body 33 in the axial direction. The mating surfaces of the housing main body 33 and the first cover 31 are perpendicular to the axial direction.

[0027] The second cover 32 covers at least a portion of the radially outer side of the coil end portion E2. That is, the second cover 32 has a portion that overlaps with the coil end portion E2 when viewed radially. The second cover 32 forms at least a portion of the wall of the space in which the coil end portion E2 at the other axial end side J2 of the housing 30 is disposed, i.e., the coil end chamber. In the example of FIG. 1 , the second cover 32 forms the axially outer and radially outer walls of the coil end chamber. The second cover 32 is assembled to the housing main body 33 in the axial direction. The mating surfaces of the housing main body 33 and the second cover 32 are surfaces perpendicular to the axial direction. The second cover 32 is fastened to the housing main body 33 by a housing fastener (not shown). The housing main body 33 is disposed axially between the first cover 31 and the second cover.

[0028] 1, the rotor 20 includes a rotor shaft 21, a rotor core 22 attached around the rotor shaft 21, and a magnet 23 serving as a magnetic flux generator provided in the rotor core 22. The magnet 23 is embedded in the rotor core 22. The rotor shaft 21 is rotatably supported by a housing 30 via bearings 31a and 32a. In the example shown in FIG. 1, a portion of the rotor shaft 21 near one end is supported by the bearing 31a of the first cover 31, and a portion of the rotor shaft 21 near the other end is supported by the bearing 32a of the second cover 32.

[0029] 1 has a cooling structure that circulates coolant inside the housing 30 to cool the stator 10. As the cooling structure, coolant flow paths 6a, 6b1, and 6b2 for passing the coolant are provided inside the wall of the housing 30. The coolant flow paths include a main body flow path 6a formed inside the wall of the housing main body 33, and cover flow paths 6b1 and 6b2 formed inside the walls of the first cover 31 and the second cover 32, respectively. The main body flow path 6a and the cover flow paths 6b1 and 6b2 are connected to each other.

[0030] The main flow passage 6a is formed over the entire circumferential direction of the wall of the housing main body 33. The main flow passage 6a is disposed radially outside the stator 10 so as to surround the outer periphery of the stator 10. Cover flow passages 6b1, 6b2 are formed extending in the axial direction from parts of the main flow passage 6a in the circumferential direction. The cover flow passages 6b1, 6b2 are provided in parts of the circumferential direction of each of the first cover 31 and the second cover 32.

[0031] 3 is a cross-sectional perspective view of the vicinity of the cover flow channels 6b1 and 6b2 shown in FIG. 1. As shown in FIG. 3, the cover flow channels 6b1 and 6b2 are formed by extending from a portion of the circumferential direction of the main flow channel 6a toward both sides in the axial direction. The cover flow channels 6b1 and 6b2 have a shape with the axial direction as the longitudinal direction. Coolant ports 71 and 72 extend from the cover flow channels 6b1 and 6b2 to reach the coil end chambers. The coolant ports 71 and 72 connect the cover flow channels 6b1 and 6b2 (coolant flow channels) with the coil end chambers. The coolant ports 71 and 72 are holes formed in the first cover 31 and the second cover 32 (housing 30).

[0032] 1 and 3, the coolant ports 71, 72 are formed at an angle with respect to a plane perpendicular to the axial direction so that they approach the axially inner side as they move inward (radially inward) of the housing 30. In this example, the coolant ports 71, 72 are drilled at an angle with respect to the thickness direction of the wall of the housing 30 (the first cover 31 and the second cover 32 in the example of FIG. 1). The inner surfaces of the coolant ports 71, 72 are inclined with respect to a plane perpendicular to the axial direction.

[0033] The coolant introduced into the housing from the coolant ports 71, 72 flows axially inward. That is, the flow direction of the coolant introduced into the housing through the coolant ports 71, 72 has a component of flowing axially inward. This makes it less likely that the flow of the coolant introduced from the coolant ports will concentrate near the coolant ports. This improves the efficiency of the coolant circulation. Furthermore, the coolant introduced from the coolant ports 71, 72 flows toward the base of the extension line 2e of the coil end portions E1, E2, i.e., near the slot of the stator core. This allows the desired portion of the coil to be cooled effectively.

[0034] Fig. 4 is a view of the vicinity of the cover flow passage 6b2 as viewed from the outside in the axial direction. In the example of Fig. 4, the coolant port 72 is formed by a plurality of holes. The plurality of holes are formed to extend in directions that separate from each other as they move inward (radially inward) of the housing 30. In the example of Fig. 4, the plurality of holes of the coolant port 72 are formed to separate circumferentially as they move from the outside to the inside of the housing 30. The coolant port 72 is configured so that it branches out from the coolant flow passage (cover flow passage 6b2) into a plurality of holes that communicate with the coil end chambers inside the housing.

[0035] The coolant introduced into the housing through the multiple holes of the coolant port 72 is easily dispersed within the housing. This prevents the flow of coolant introduced through the coolant port from concentrating near the coolant port. This improves the efficiency of coolant circulation. Furthermore, the coolant is more likely to flow over a wide range in the circumferential direction of the coil end portion E2. This allows the desired portion of the coil to be cooled effectively.

[0036] FIG. 5 is a diagram showing a modification of the multiple holes of the coolant port 72 shown in FIG. 4 . In the example shown in FIG. 4 , the roots of the multiple holes of the coolant port 72 are connected, whereas in the example shown in FIG. 5 , the multiple holes are formed by extending independently from the coolant flow path (cover flow path 6 b 2). That is, in the example shown in FIG. 4 , the portion of the coolant port 72 that exits the coolant flow path is a single hole, and multiple holes branch off from this single hole and reach the inside of the housing. In contrast, in the example shown in FIG. 5 , multiple holes extend from the coolant flow path and reach the inside of the housing. While FIGS. 4 and 5 show examples of the coolant port 72 of the second cover 32, the coolant port 71 of the first cover 31 can also be formed with multiple holes.

[0037] (Example of Coolant Flow) FIGS. 6 and 7 are diagrams illustrating an example of the flow of coolant in the motor 100. FIG. 6 is a perspective view showing a cross section of the second cover 32 taken along a plane perpendicular to the axial direction. FIG. 7 is a perspective view showing a cross section of the first cover 31 taken along a plane perpendicular to the axial direction. In the example shown in FIG. 6 , the housing main body 33 has external flow path openings 83, 83a. The external flow path openings 83, 83a are holes that communicate between the coolant flow path (main body flow path 6a) of the housing main body 33 and the outside of the housing 30. The external flow path openings 83, 83a are holes formed in the outer peripheral wall of the housing main body 33. The external flow path opening 83 is provided on the opposite side of the coolant port 72 with respect to the rotation axis J of the rotor. The external flow path opening 83 is also provided on the opposite side of the cover flow path 6b2 with respect to the rotation axis J of the rotor.

[0038] When viewed from the axial direction, the flow path external ports 83, 83a and the coolant port 72 may be arranged so that at least a portion of the rotor 20 is located between the flow path external ports 83, 83a and the coolant port 72. For example, when viewed from the axial direction, the flow path external ports 83 and the coolant port 72 may be arranged so that an arbitrary imaginary line K2 passing through the flow path external port 83 and the coolant port 72 passes through the arrangement region of the rotor 20. As a result, the flow path external port 83 and the coolant port 72 are arranged at positions spaced apart to some extent in the circumferential direction.

[0039] In the example of Fig. 6, the second cover 32 has an internal / external communication port 82. The internal / external communication port 82 is a hole that communicates between the coil end chamber and the outside of the housing 30. The internal / external communication port 82 is a hole formed in the outer peripheral wall of the second cover 32. The internal / external communication port 82 is provided on the opposite side of the rotation axis J of the rotor from the coolant port 72. The internal / external communication port 82 is also provided on the opposite side of the rotation axis J of the rotor from the cover flow path 6b2.

[0040] The interior / exterior communicating port 82 and the coolant port 72 may be arranged such that, as viewed from the axial direction, at least a portion of the rotor 20 is located between the interior / exterior communicating port 82 and the coolant port 72. For example, the interior / exterior communicating port 82 and the coolant port 72 may be arranged such that, as viewed from the axial direction, an arbitrary imaginary line K2 passing through the interior / exterior communicating port 82 and the coolant port 72 passes through the arrangement area of ​​the rotor 20. As a result, the interior / exterior communicating port 82 and the coolant port 72 are arranged at positions spaced apart to some extent in the circumferential direction.

[0041] 6 , the coolant that enters the coolant flow path 6a of the housing main body 33 from the flow path external port 83 passes through the coolant flow path (main body flow path) 6a to reach the cover flow path 6b2, and is then introduced from the cover flow path 6b2 into the coil end chamber via the coolant port 72. The coolant travels approximately halfway around the wall of the housing main body 33 on the outer periphery of the stator core 1 before reaching the coolant port 72 from the flow path external port 83. This makes it easier to release heat from the outer periphery of the stator core 1.

[0042] The coolant that enters the coil end chamber from the coolant port 72 flows through the coil end chamber, reaches the internal / external communication port 82, and is discharged to the outside of the housing 30. From the coolant port 72 to the internal / external communication port 82, the coolant travels approximately halfway around the coil end portion E2 of the stator 10 while coming into contact with the coil end portion E2. This facilitates heat release from the coil of the stator 10. In this way, by arranging the flow path external port 83 and the coolant port 72, and the internal / external communication port 82 and the coolant port 72 at positions that are spaced apart in the circumferential direction, heat is facilitated to release from both the outer periphery of the stator core 1 and the coil end portion E2 of the stator 10 inside the housing. This enables efficient cooling.

[0043] 7 , the housing main body 33 has an external flow path port 83b in addition to the external flow path port 83. The external flow path port 83 is located on the opposite side of the coolant port 71 of the first cover 31 with respect to the rotor's rotation axis J. In this way, by providing the external flow path port 83b between the external flow path port 83, which is located on the opposite side of the rotor's rotation axis J from the coolant port 71, and the coolant port 71, it is possible to promote circulation of the coolant.

[0044] When viewed from the axial direction, the flow path external ports 83, 83b and the coolant port 71 may be arranged so that at least a portion of the rotor 20 is located between the flow path external ports 83, 83b and the coolant port 71. For example, when viewed from the axial direction, the flow path external ports 83 and the coolant port 71 may be arranged so that an arbitrary imaginary line K1 passing through the flow path external port 83 and the coolant port 71 passes through the arrangement area of ​​the rotor 20. As a result, the flow path external ports 83, 83b and the coolant port 72 are arranged at positions spaced apart to some extent in the circumferential direction.

[0045] In the example of FIG. 7 , the first cover 31 has an interior / exterior communication port 81. The interior / exterior communication port 81 is provided on the opposite side of the coolant port 71 with respect to the rotation axis J of the rotor. The interior / exterior communication port 81 and the coolant port 71 may be arranged so that at least a portion of the rotor 20 is located between the interior / exterior communication port 81 and the coolant port 71 when viewed from the axial direction. For example, the interior / exterior communication port 81 and the coolant port 71 may be arranged so that an arbitrary imaginary line K1 passing through the interior / exterior communication port 81 and the coolant port 71 passes through the arrangement area of ​​the rotor 20 when viewed from the axial direction. As a result, the interior / exterior communication port 81 and the coolant port 71 are arranged at positions spaced apart to a certain extent in the circumferential direction.

[0046] 7, as in the example of Fig. 6, the coolant travels approximately halfway around the wall of the housing main body 33 on the outer periphery of the stator core 1 from the flow path external port 83 until it reaches the coolant port 71. In addition, the coolant travels approximately halfway around the coil end portion E1 of the stator 10 from the coolant port 71 until it reaches the inside-outside communication port 81. This allows for efficient cooling.

[0047] In this embodiment, the housing 30 includes a coolant reservoir that seals and retains coolant in the space (coil end chamber) where the coil end portions E1 and E2 are located. This allows the coil end chamber to be filled with coolant, allowing the coil end portions E1 and E2 to be cooled while immersed in the coolant. With the coil end chamber filled with coolant, the coolant is introduced into the coil end chamber through the coolant ports 71 and 72 via the coolant flow paths 6a, 6b1, and 6b2, thereby circulating the coolant. In this configuration, forming the coolant ports 71 and 72 at an angle, as in the above example, reduces the concentration of the coolant flow near the coolant ports 71 and 72, allowing the coolant to circulate efficiently through the coil end portions. Furthermore, forming the coolant ports 71 and 72 by drilling them at an angle relative to the wall thickness direction facilitates cutting.

[0048] 1 , a cylindrical sealing member 9 is provided to keep the coolant accommodating section liquid-tight. The sealing member 9 is inserted between the stator core 1 and the rotor 20. A seal member is provided between the sealing member 9 and the housing 30. As a result, the coil end chamber is surrounded by the first cover 31 or the second cover 32, the housing main body 33, the stator core 1, and the sealing member 9, and serves as a coolant accommodating section that is kept liquid-tight. The sealing member 9 separates the coolant accommodating section from a rotor accommodating section in which the rotor 20 is accommodated.

[0049] In the example shown in FIG. 1 , a spacer 11 is provided in the coil end chamber between the coil end portions E1, E2 and the inner wall of the housing 30. The spacer 11 limits the area of ​​the coil end chamber filled with coolant to the vicinity of the coil end portions. For example, as shown in FIGS. 6 and 7 , the spacer 11 may be disposed radially outward of the coil end portions E1, E2 and extend circumferentially. In this case, the spacer 11 is not provided in the space between the coolant ports 71, 72 and the coil end portions E1, E2. This facilitates the flow of coolant from the coolant ports 71, 72 to the coil end portions E1, E2. Furthermore, the surface of the spacer 11 may be provided so as to widen radially inward on both circumferential sides of the space between the coolant ports 71, 72 and the coil end portions E1, E2 (see FIGS. 4 to 7 ). This facilitates the flow of coolant from the coolant ports 71, 72 to the coil end portions E1, E2.

[0050] In the above example, a coolant port is provided in each of the first cover 31 and the second cover 32. As a variation of this, the coolant port may be provided in, for example, the housing main body, or may be provided in only either the first cover or the second cover. Furthermore, a coolant flow path that allows coolant to flow around the entire outer periphery of the stator 10 may be provided in at least one of the first cover 31 or the second cover 32.

[0051] In the above embodiment, the motor is typically a three-phase AC motor. The coil groups for each of the U, V, and W phases may have at least two parallel coils. While the motor 100 is an interior permanent magnet synchronous motor in the above embodiment, the configuration of the motor 100 is not limited to this. For example, the motor may be a reluctance synchronous motor or an induction motor. Furthermore, the motor 100 may be used as a power source that outputs driving force, or as a generator.

[0052] Although the embodiments of the present invention have been described above, the above-described embodiments are merely examples for carrying out the present invention. Therefore, the present invention is not limited to the above-described embodiments, and the above-described embodiments can be appropriately modified and carried out within the scope of the gist of the present invention.

[0053] 1: stator core, 2s: slot line portion, 2e: extension line, 6a, 6b1, 6b2: coolant flow path, 10: stator, 20: rotor, 30: housing, 31: first cover, 32: second cover, 33: housing body, E1, E2: coil end portion, 71, 72: coolant port, 81, 82: internal / external communication port, 83, 83a, 83b: flow path external port

Claims

1. A motor comprising: a housing; a stator accommodated in the housing; and a rotor disposed inside the stator and rotatably supported by the housing, the stator having a stator core having a plurality of slots, and coils formed of conductors inserted into the slots, the conductors of the coils including slot wire portions housed in the slots and coil end portions constituted by extension wires extending from the slots to the outside in the axial direction of the stator core, the housing having a coolant flow path formed inside a wall constituting the housing for passing a coolant, and a coolant port, radially outside the coil end portion, communicating between the coolant flow path and a space within the housing in which the coil end portion is disposed, the coolant port being formed at an angle with respect to a plane perpendicular to the axial direction so as to approach the axial inner side as it extends inward of the housing.

2. A motor comprising: a housing; a stator accommodated in the housing; and a rotor disposed inside the stator and rotatably supported by the housing, wherein the stator has a stator core having a plurality of slots, and coils formed of conductors inserted into the slots, the conductors of the coils including slot wire portions housed in the slots and coil end portions constituted by extension wires extending from the slots to the outside in the axial direction of the stator core, wherein the housing has a coolant flow path formed inside a wall constituting the housing for passing a coolant, and a coolant port, radially outside the coil end portion, communicating between the coolant flow path and a space within the housing in which the coil end portion is disposed, and the coolant port is formed of a plurality of holes formed extending in directions that move away from each other as they approach the inside of the housing.

3. A motor as claimed in claim 1 or 2, wherein the housing has a housing main body which holds the stator core and a cover which covers at least a portion of the radially outer side of the coil end portion, the coolant flow path is formed across both the housing main body and the cover, and the coolant port communicates between a cover flow path formed in the cover among the coolant flow paths and a space in the housing in which the coil end portion is disposed.

4. A motor as claimed in claim 3, wherein the housing body has an external flow path opening which communicates between the cooling liquid flow path and the outside of the housing, and the external flow path opening and the cooling liquid opening are arranged so that, when viewed in the axial direction, at least a part of the rotor is located between the external flow path opening and the cooling liquid opening.

5. A motor as claimed in claim 3 or 4, wherein the cover includes a first cover assembled to one axial end side of the housing body and a second cover assembled to the other axial end side of the housing body, the coolant flow path is formed across the housing body, the first cover and the second cover, and the coolant port is formed in each of the first cover and the second cover.

6. A motor as claimed in any one of claims 1 to 5, wherein the housing has an internal / external communication port that connects the space within the housing in which the coil end portions are arranged with the outside of the housing, and the internal / external communication port and the coolant port are arranged so that, when viewed in the axial direction, at least a part of the rotor is located between the internal / external communication port and the coolant port.

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