Motor

Abstract

To suppress imbalance of a flow rate of a coolant in a plurality of individual flow paths.SOLUTION: A motor includes: a stator disposed such that a central axis intersects a vertical direction; an annular coolant flow path provided along an end surface of the stator and having a ring shape extending around the central axis; and a plurality of individual flow paths each of which is connected to the annular coolant flow path and through which a coolant supplied from the annular coolant flow path flows. The annular coolant flow path has a partition structure that partitions the annular coolant flow path into an upper flow path and a lower flow path located below the upper flow path. The plurality of individual flow paths include a plurality of upper individual flow paths connected to the upper flaw path and a plurality of lower individual flow paths connected to the lower flow path.SELECTED DRAWING: Figure 5

Description

Technical Field

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

[0002] The motor disclosed in Patent Document 1 has an annular coolant flow path provided along the end face of the stator. The annular coolant flow path has a ring shape extending around the central axis of the stator. Also, this motor has a plurality of coolant flow paths inside the stator provided inside the stator. Each coolant flow path inside the stator is connected to the annular coolant flow path. Coolant flows from the annular coolant flow path into each coolant flow path inside the stator. The motor is cooled by the coolant.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, the coolant flow path inside the stator is connected to the annular coolant flow path. Also, in other motors, another flow path (for example, a flow path that discharges coolant toward the coil end of the stator) may be connected to the annular coolant flow path. Hereinafter, a plurality of flow paths branching from the annular coolant flow path are referred to as individual flow paths.

[0005] When the central axis of the motor is arranged in a direction intersecting the vertical direction (for example, the central axis of the motor is horizontal), a height difference occurs inside the annular coolant flow path. In this case, the pressure becomes higher at the lower part of the annular coolant flow path than at the upper part. For this reason, more coolant flows through the individual flow paths connected to the lower part of the annular coolant flow path than through the individual flow paths connected to the upper part of the annular coolant flow path. Thus, when the flow rate of the coolant becomes unbalanced among the plurality of individual flow paths, the motor cannot be efficiently cooled. In this specification, a technique for suppressing the imbalance in the flow rate of the coolant among the plurality of individual flow paths is proposed.

Means for Solving the Problems

[0006] The motor of Configuration 1 disclosed in this specification includes a stator arranged such that its central axis intersects the vertical direction, an annular coolant flow path provided along the end face of the stator and having a ring shape extending around the central axis, and a plurality of individual flow paths each connected to the annular coolant flow path and through which the coolant supplied from the annular coolant flow path flows. The annular coolant flow path has a partitioning structure that partitions the annular coolant flow path into an upper flow path and a lower flow path located below the upper flow path. The plurality of the individual flow paths include a plurality of upper individual flow paths connected to the upper flow path and a plurality of lower individual flow paths connected to the lower flow path.

[0007] Note that the entire lower flow path may be arranged below the lower end of the upper flow path, or a part of the lower flow path may be arranged below the lower end of the upper flow path.

[0008] Also, the partitioning structure is a structure that partitions the upper flow path and the lower flow path so as to suppress the pressure interaction between them. The partitioning structure may completely separate the upper flow path and the lower flow path, or the upper flow path and the lower flow path may be partially connected in the partitioning structure.

[0009] In this motor, the annular coolant flow path is partitioned into an upper flow path and a lower flow path by a partitioning structure. Therefore, it is difficult for pressure to be applied from the upper flow path to the lower flow path, and it is difficult for the pressure in the lower flow path to increase. Therefore, the coolant easily flows evenly in the individual flow paths connected to the upper flow path and the individual flow paths connected to the lower flow path. Thus, according to this motor, an imbalance in the coolant flow rate among the plurality of individual flow paths can be suppressed.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

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Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

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Figure 17

Embodiments for Carrying Out the Invention

[0011] Following the above Configuration 1, additional configurations of the vehicle disclosed in this specification will be described below.

[0012] (Configuration 2) The partition structure is a partition wall that separates the upper flow path from the lower flow path, and further includes an upper coolant supply flow path for supplying coolant to the upper flow path and a lower coolant supply flow path for supplying coolant to the lower flow path. The motor according to Configuration 1. (Configuration 3) The partition structure is a partial partition wall that reduces the cross-section of the annular coolant flow path, and further includes a coolant supply flow path for supplying coolant to the upper flow path. The motor according to Configuration 1. (Configuration 4) The partition structure is a check valve that allows the flow of coolant from the upper flow path to the lower flow path and blocks the flow of coolant from the lower flow path to the upper flow path, and further includes a coolant supply flow path for supplying coolant to the upper flow path. The motor according to Configuration 1. (Configuration 5) It further includes a coil wound around the stator and having a coil end disposed on the inner peripheral portion of the annular coolant flow path, and a plurality of the individual flow paths have a plurality of coolant discharge flow paths that discharge coolant toward the coil end. The motor according to any one of Configurations 1 to 4. (Configuration 6) A plurality of the individual flow paths have a plurality of stator internal coolant flow paths provided inside the stator. The motor according to any one of Configurations 1 to 5. (Configuration 7) A motor, A stator arranged such that its central axis intersects the vertical direction, An annular coolant flow path provided along the end face of the stator and having an annular shape extending around the central axis, A coil wound around the stator and having coil ends disposed on the inner peripheral portion of the annular coolant flow path, A plurality of coolant discharge flow paths each connected to the annular coolant flow path and discharging the coolant supplied from the annular coolant flow path toward the coil ends, having, The total cross-sectional area of the coolant discharge flow paths connected to the annular coolant flow path above the central position in the vertical direction of the annular coolant flow path is larger than the total cross-sectional area of the coolant discharge flow paths connected to the annular coolant flow path below the central position, a motor. (Configuration 8) A plurality of coolant flow paths inside the stator, each provided inside the stator, each connected to the annular coolant flow path, and through which the coolant supplied from the annular coolant flow path flows, further having, The total cross-sectional area of the coolant flow paths inside the stator connected to the annular coolant flow path above the central position is larger than the total cross-sectional area of the coolant flow paths inside the stator connected to the annular coolant flow path below the central position, The motor according to Configuration 7.

[0013] In the motor of Configuration 8, the total cross-sectional area of the coolant discharge flow paths connected to the annular coolant flow path on the upper side is larger than the total cross-sectional area of the coolant discharge flow paths connected to the annular coolant flow path on the lower side of the central position. For this reason, even if the pressure in the annular coolant flow path becomes higher on the lower side than on the upper side, the coolant easily flows evenly through each coolant discharge flow path.

[0014] In the motor of Configuration 9, the total cross-sectional area of the coolant flow paths in the stator, which are connected to the annular coolant flow path on the upper side, is larger than the total cross-sectional area of the coolant flow paths in the stator, which are connected to the annular coolant flow path below the central position. Therefore, even if the pressure in the annular coolant flow path becomes higher on the lower side than on the upper side, the coolant can easily flow evenly through each coolant flow path in the stator.

[0015] In Configurations 7 and 8, the "cross-sectional area" means the cross-sectional area at the narrowest position of each flow path. For example, when the cross-sectional area of a specific flow path varies depending on the position in the flow direction, the minimum value of the cross-sectional area of that flow path corresponds to the "cross-sectional area" in Configurations 7 and 8.

Example

[0016] The motor 10 of Example 1 shown in FIGS. 1 and 2 has a rotor 20, a stator 30, and a case 50. The rotor 20 has a shaft 24. The stator 30 has a cylindrical shape. The rotor 20 is arranged in the central hole of the stator 30 such that the central axis of the shaft 24 coincides with the central axis AX of the stator 30. The rotor 20 and the stator 30 are accommodated in the case 50. The stator 30 is fastened to the case 50 by bolts 49. Hereinafter, the direction parallel to the central axis AX is referred to as the axial direction, the direction along the radius of the circle centered on the central axis AX is referred to as the radial direction, and the direction along the circumference of the circle centered on the central axis AX is referred to as the circumferential direction. Also, the arrow UP in FIG. 2 indicates the upper side in the vertical direction. The motor 10 is arranged such that the central axis AX intersects the upward direction UP. In FIG. 2, the central axis AX is orthogonal to the upward direction UP. In other words, in FIG. 2, the central axis AX is horizontally arranged. In other examples, the central axis AX may be inclined with respect to the horizontal plane.

[0017] As shown in FIGS. 1 and 2, the case 50 has a so-called bottomed cylindrical shape and has an outer peripheral wall 52 and a side wall 54. The outer peripheral wall 52 has a cylindrical shape. The side wall 54 is provided at one end of the outer peripheral wall 52 in the axial direction. A through hole 54a is provided at the center of the side wall 54.

[0018] The stator 30 has a stator core 32 and a coil 40. In FIG. 2, the coil 40 is shown in a simplified manner. The stator core 32 has a cylindrical shape. As shown in FIG. 3, the stator core 32 is composed of a plurality of electromagnetic steel sheets 36 laminated in the axial direction. The stator core 32 has a back yoke 33 and a plurality of teeth 34. The back yoke 33 has a cylindrical shape. Each tooth 34 protrudes from the inner peripheral surface of the back yoke 33. That is, each tooth 34 protrudes radially inward from the back yoke 33. Each tooth 34 extends along the axial direction. The plurality of teeth 34 are arranged at intervals in the circumferential direction. The coil 40 is wound around each tooth 34. The stator core 32 has an end face 32a and an end face 32b. The end face 32a is one end face of the stator core 32 in the axial direction, and the end face 32b is the end face on the opposite side of the end face 32a. As shown in FIG. 2, a coil end 42a is provided on the end face 32a. A coil end 42b is provided on the end face 32b. The coil ends 42a and 42b are bent portions of the coil 40 wound around the stator core 32. The coil end 42a protrudes from the end face 32a, and the coil end 42b protrudes from the end face 32b. As shown in FIG. 4, the coil end 42a is distributed annularly on the end face 32a. Similarly, the coil end 42b is distributed annularly on the end face 32b.

[0019] As shown in FIGS. 1 and 2, the side wall 54 of the case 50 faces the end face 32a of the stator core 32. A gap is provided between the side wall 54 and the end face 32a of the stator core 32, and the coil end 42a is arranged within the gap.

[0020] The rotor 20 is arranged within the central hole of the stator core 32 in a state concentric with the stator core 32. The shaft 24 of the rotor 20 is inserted through the through hole 54a of the case 50. The rotor 20 is rotatably supported within the case 50 by bearings or the like.

[0021] As shown in FIGS. 1 and 2, the motor 10 has a guide ring 60. The guide ring 60 has a ring shape. The guide ring 60 is housed in the case 50. The guide ring 60 is arranged to extend annularly around the central axis AX of the stator 30. The guide ring 60 is arranged between the end face 32a of the stator core 32 and the side wall 54 of the case 50 in a state concentric with the stator core 32. The guide ring 60 is fixed to the end face 32a. An annular coolant flow path 62 is provided in the guide ring 60. The annular coolant flow path 62 extends along the end face 32a of the stator core 32. As shown in FIG. 4, the annular coolant flow path 62 has a ring shape extending around the central axis AX of the stator. The coil end 42a is arranged inside the guide ring 60 (i.e., the annular coolant flow path 62) in the radial direction.

[0022] During the operation of the motor 10, coolant flows through the coolant flow path including the annular coolant flow path 62, and the motor 10 is cooled. In this embodiment, the coolant is cooling oil. The cooling oil functions as a coolant for cooling the motor 10 and also functions as a lubricating oil for lubricating the rotor 20.

[0023] As shown in FIGS. 2 and 5, in the first embodiment, a plurality of coolant discharge flow paths 68 are provided in the guide ring 60. Each coolant discharge flow path 68 is provided in the wall constituting the inner peripheral surface of the guide ring 60. That is, each coolant discharge flow path 68 extends from the annular coolant flow path 62 to the inner peripheral surface of the guide ring 60. The plurality of coolant discharge flow paths 68 are provided at substantially equal angular intervals in the circumferential direction. As indicated by the arrows in FIG. 5, each coolant discharge flow path 68 discharges the coolant in the annular coolant flow path 62 toward the inside of the guide ring 60. As described above, the coil end 42a is arranged inside the guide ring 60. Therefore, each coolant discharge flow path 68 discharges the coolant toward the coil end 42a.

[0024] As shown in FIG. 5, partitions 64a and 64b are provided inside the annular coolant flow path 62. By the partitions 64a and 64b, the annular coolant flow path 62 is divided into an upper flow path 62a and a lower flow path 62b. A plurality of coolant discharge flow paths 68 are connected to each of the upper flow path 62a and the lower flow path 62b.

[0025] As shown in FIGS. 2 and 5, an upper coolant supply flow path 66a and a lower coolant supply flow path 66b are connected to the guide ring 60. The upper coolant supply flow path 66a connects the outside of the case 50 and the upper flow path 62a. The lower coolant supply flow path 66b connects the outside of the case 50 and the lower flow path 62b. As shown in FIG. 2, a coolant discharge path 53b is provided at the lower part of the case 50. The coolant discharge path 53b connects the inside and the outside of the case 50.

[0026] When the motor 10 is operating, coolant is supplied to the upper coolant supply flow path 66a and the lower coolant supply flow path 66b by a pump (not shown). The coolant flows from the upper coolant supply flow path 66a into the upper flow path 62a, and the coolant flows from the lower coolant supply flow path 66b into the lower flow path 62b. The coolant in the upper flow path 62a is discharged toward the coil end 42a through the coolant discharge flow path 68, and the coolant in the lower flow path 62b is discharged toward the coil end 42a through the coolant discharge flow path 68. The coolant discharged toward the coil end 42a flows down inside the case 50 and is discharged from the case 50 to the outside through the coolant discharge path 53b. The coolant discharged from the coolant discharge path 53b is supplied again to the upper coolant supply flow path 66a and the lower coolant supply flow path 66b by the pump. By circulating the coolant in this way, the motor 10 is cooled.

[0027] In Example 1, since the lower channel 62b is separated from the upper channel 62a by the partition walls 64a and 64b, the pressure in the upper channel 62a and the pressure in the lower channel 62b are independent. Therefore, it is possible to prevent the pressure in the lower channel 62b from becoming extremely high with respect to the pressure in the upper channel 62a. Accordingly, an imbalance between the flow rate of the coolant flowing through the coolant discharge channel 68 provided in the upper channel 62a and the flow rate of the coolant flowing through the coolant discharge channel 68 provided in the lower channel 62b is suppressed. For this reason, according to Example 1, the coil end 42a can be cooled uniformly.

[0028] In Example 1, the partition walls 64a and 64b were arranged at the same height. However, as illustrated in FIG. 6, the partition walls 64a and 64b may be arranged at different heights.

Example

[0029] In Example 2, the partitioning structure that partitions the upper channel 62a and the lower channel 62b and the coolant supply channel are different from those in Example 1. Other configurations of Example 2 are the same as those of Example 1.

[0030] As shown in FIG. 7, in Example 2, the upper channel 62a and the lower channel 62b are partitioned by partial partition walls 64c and 64d. The partial partition wall 64c partially blocks the annular coolant channel 62, and a microchannel 64e is provided adjacent to the partial partition wall 64c. The microchannel 64e connects the upper channel 62a and the lower channel 62b. The cross-sectional area of the microchannel 64e is smaller than the cross-sectional area of the upper channel 62a and the cross-sectional area of the lower channel 62b. That is, the partial partition wall 64c reduces the cross-section of the annular coolant channel 62. The partial partition wall 64c may be a throttling mechanism such as an orifice. Similar to the partial partition wall 64c, the partial partition wall 64d also partially blocks the annular coolant channel 62, and a microchannel 64f is arranged adjacent to the partial partition wall 64d. The microchannel 64f connects the upper channel 62a and the lower channel 62b. The cross-sectional area of the microchannel 64f is smaller than the cross-sectional area of the upper channel 62a and the cross-sectional area of the lower channel 62b.

[0031] In Example 2, similar to Example 1, an upper coolant supply channel 66a connected to the upper channel 62a is provided. On the other hand, in Example 2, a lower coolant supply channel 66b connected to the lower channel 62b is not provided.

[0032] When the motor in Example 2 operates, coolant is supplied to the upper channel 62a through the upper coolant supply channel 66a by a pump (not shown). Since micro-channels 64e and 64f are provided adjacent to the partial partitions 64c and 64d, the coolant flows from the upper channel 62a to the lower channel 62b through the micro-channels 64e and 64f. The coolant in the upper channel 62a is discharged toward the coil end 42a through the coolant discharge channel 68, and the coolant in the lower channel 62b is discharged toward the coil end 42a through the coolant discharge channel 68. Since the upper channel 62a and the lower channel 62b are partitioned by the partial partitions 64c and 64d, the pressure applied from the upper channel 62a to the lower channel 62b is reduced. Therefore, it is prevented that the pressure in the lower channel 62b becomes extremely higher than the pressure in the upper channel 62a. Accordingly, the imbalance between the flow rate of the coolant flowing through the coolant discharge channel 68 provided in the upper channel 62a and the flow rate of the coolant flowing through the coolant discharge channel 68 provided in the lower channel 62b is suppressed. For this reason, according to Example 2, the coil end 42a can be cooled uniformly.

Example

[0033] In Example 3, the partitioning structure that partitions the upper channel 62a and the lower channel 62b and the coolant supply channel are different from those in Example 1. Other configurations of Example 3 are the same as those in Example 1.

[0034] As shown in FIG. 8, in Example 3, the upper channel 62a and the lower channel 62b are partitioned by check valves 64g and 64h. Each of the check valve 64g and the check valve 64h allows the flow of coolant from the upper channel 62a to the lower channel 62b and blocks the flow of coolant from the lower channel 62b to the upper channel 62a.

[0035] In Example 3, similar to Example 2, while there is an upper coolant supply channel 66a connected to the upper channel 62a, there is no lower coolant supply channel 66b connected to the lower channel 62b.

[0036] When the motor in Example 3 operates, coolant is supplied to the upper channel 62a through the upper coolant supply channel 66a by a pump (not shown). The coolant flows from the upper channel 62a to the lower channel 62b through check valves 64g and 64h. The coolant in the upper channel 62a is discharged toward the coil end 42a through the coolant discharge channel 68, and the coolant in the lower channel 62b is discharged toward the coil end 42a through the coolant discharge channel 68. Since the upper channel 62a and the lower channel 62b are partitioned by the check valves 64g and 64h, the pressure applied from the upper channel 62a to the lower channel 62b is reduced. Therefore, it is prevented that the pressure in the lower channel 62b becomes extremely higher than the pressure in the upper channel 62a. Accordingly, the imbalance between the flow rate of the coolant flowing through the coolant discharge channel 68 provided in the upper channel 62a and the flow rate of the coolant flowing through the coolant discharge channel 68 provided in the lower channel 62b is suppressed. For this reason, according to Example 3, the coil end 42a can be cooled uniformly.

[0037] In Examples 1 to 3, the coolant discharge channel 68 is an example of an individual channel. More specifically, the coolant discharge channel 68 connected to the upper channel 62a is an example of an upper individual channel, and the coolant discharge channel 68 connected to the lower channel 62b is an example of a lower individual channel.

Example

[0038] As shown in FIGS. 9 and 10, in Example 4, the motor does not have a coolant discharge passage 68, but instead has a plurality of coolant passages 70 within the stator. Other configurations of Example 4 are the same as those of Example 1. Each coolant passage 70 within the stator is provided inside the stator core 32. As shown in FIG. 9, each coolant passage 70 within the stator extends axially from one end face 32a of the stator core 32 to the other end face 32b. The upstream end of each coolant passage 70 within the stator is connected to the annular coolant passage 62. The downstream end of each coolant passage 70 within the stator opens to the end face 32b. As shown in FIG. 10, the upstream ends of the coolant passages 70 within the stator are provided at equal angular intervals in the circumferential direction. A plurality of coolant passages 70 within the stator are connected to the upper passage 62a, and a plurality of coolant passages 70 within the stator are connected to the lower passage 62b.

[0039] When the motor of Example 4 operates, coolant is supplied to the upper coolant supply passage 66a and the lower coolant supply passage 66b by a pump (not shown). The coolant flows from the upper coolant supply passage 66a into the upper passage 62a, and the coolant flows from the lower coolant supply passage 66b into the lower passage 62b. The coolant in the upper passage 62a flows through the coolant passage 70 within the stator and is discharged from its downstream end (i.e., the end face 32b). The coolant in the lower passage 62b flows through the coolant passage 70 within the stator and is discharged from its downstream end (i.e., the end face 32b). The stator core 32 is cooled from the inside by the coolant flowing through each coolant passage 70 within the stator. The coolant discharged from the downstream end of each coolant passage 70 within the stator flows down through the case 50 and is discharged to the outside of the case 50 through the coolant discharge passage 53b. The coolant discharged from the coolant discharge passage 53b is supplied again to the upper coolant supply passage 66a and the lower coolant supply passage 66b by the pump. By circulating the coolant in this way, the motor 10 is cooled.

[0040] In Embodiment 4, since the lower channel 62b is separated from the upper channel 62a by the partition walls 64a and 64b, the pressure in the upper channel 62a and the pressure in the lower channel 62b are independent. Therefore, it is possible to prevent the pressure in the lower channel 62b from becoming extremely high relative to the pressure in the upper channel 62a. Accordingly, an imbalance between the flow rate of the coolant flowing through the coolant flow path 70 in the stator connected to the upper channel 62a and the flow rate of the coolant flowing through the coolant flow path 70 in the stator connected to the lower channel 62b is suppressed. For this reason, according to Embodiment 4, the stator core 32 can be cooled uniformly.

[0041] In Embodiment 4, the coolant flow path 70 in the stator is an example of an individual flow path. More specifically, the coolant flow path 70 connected to the upper channel 62a is an example of an upper individual flow path, and the coolant flow path 70 connected to the lower channel 62b is an example of a lower individual flow path.

[0042] Note that, in Embodiment 4 (i.e., FIG. 10), the upper channel 62a and the lower channel 62b were partitioned by the partition walls 64a and 64b, but the partitioning structure of Embodiment 2 shown in FIG. 7 (i.e., the partial partition wall), or the partitioning structure of Embodiment 3 shown in FIG. 8 (i.e., the check valve) may be applied to Embodiment 4.

[0043] Further, the motor of Embodiment 4 had the coolant flow path 70 in the stator while not having the coolant discharge flow path 68. However, as shown in FIG. 11, the motor may have both the coolant discharge flow path 68 and the coolant flow path 70 in the stator. Even in this case, by adopting the same partitioning structure as in Embodiments 1 to 4, an imbalance in the flow rate between the respective coolant discharge flow paths 68 and an imbalance in the flow rate between the respective coolant flow paths 70 in the stator can be suppressed.

Embodiment

[0044] In Embodiment 5, the structure of the guide ring 60 is different from that of Embodiment 1. Except for the guide ring 60, Embodiment 5 is the same as Embodiment 1.

[0045] As shown in FIG. 12, in Example 5, no partitioning structure is provided in the annular coolant flow path 62 inside the guide ring 60. That is, the annular coolant flow path 62 is annularly connected and has a constant flow path cross-sectional area over its entire circumference. A coolant supply flow path 66 is connected to the guide ring 60. The guide ring 60 is provided with a plurality of coolant discharge flow paths 68. Similar to Example 1, each coolant discharge flow path 68 discharges coolant toward the coil end 42a. Different from Example 1, in Example 5, no coolant discharge flow path 68 is provided at the lowermost part of the annular coolant flow path 62. Except for the lowermost part, the coolant discharge flow paths 68 are provided at equal angular intervals in the circumferential direction of the guide ring 60. For this reason, the number of coolant discharge flow paths 68 connected to the annular coolant flow path 62 above the center position CH in the vertical direction of the annular coolant flow path 62 (that is, the horizontal line passing through the center of the circle of the annular coolant flow path 62) is larger than the number of coolant discharge flow paths 68 connected to the annular coolant flow path 62 below the center position CH. Also, the cross-sectional areas of the respective coolant discharge flow paths 68 are equal. Therefore, the total value of the cross-sectional areas of the coolant discharge flow paths 68 connected to the annular coolant flow path 62 above the center position CH is larger than the total value of the cross-sectional areas of the coolant discharge flow paths 68 connected to the annular coolant flow path 62 below the center position CH. When there is a coolant discharge flow path 68c provided at the center position CH as shown in FIG. 12, the cross-sectional area is distributed according to the ratio between the upper side and the lower side of the center position CH to calculate the above total value.

[0046] During the operation of the motor of Example 5, the coolant is supplied to the annular coolant flow path 62 through the coolant supply flow path 66 by a pump (not shown). The coolant in the annular coolant flow path 62 is discharged from each coolant discharge flow path 68 toward the coil end 42a. In Example 5, since no partitioning structure is provided in the annular coolant flow path 62, the pressure in the annular coolant flow path 62 is higher below the center position CH than above the center position CH due to the influence of gravity. On the other hand, as described above, the total cross-sectional area of the coolant discharge flow paths 68 above the center position CH is larger than the total cross-sectional area of the coolant discharge flow paths 68 below the center position CH. That is, the overall flow path resistance of the coolant discharge flow paths 68 above the center position CH is smaller than the overall flow path resistance of the coolant discharge flow paths 68 below the center position CH. Therefore, even if there is a pressure difference between above and below the center position CH, it is difficult for a difference to occur between the flow rate of the coolant discharged to the coil end 42a above the center position CH and the flow rate of the coolant discharged to the coil end 42a below the center position CH. Thus, according to Example 5, the coil end 42a can be cooled uniformly.

Example

[0047] As shown in FIG. 13, in Example 6, the motor has an in-stator coolant flow path 70 in addition to the coolant discharge flow path 68. Other configurations of Example 6 are the same as those of Example 5. Each in-stator coolant flow path 70 axially penetrates the stator core 32, similar to Example 4 (i.e., FIG. 9). As shown in FIG. 13, the upstream end of each in-stator coolant flow path 70 is connected to the annular coolant flow path 62.

[0048] In Embodiment 6, the coolant flow path 70 inside the stator is not provided at the lowermost part of the annular coolant flow path 62. Except for the lowermost part, the coolant flow paths 70 inside the stator are provided at equal angular intervals in the circumferential direction of the guide ring 60. For this reason, the number of coolant flow paths 70 inside the stator connected to the annular coolant flow path 62 above the center position CH is larger than the number of coolant flow paths 70 inside the stator connected to the annular coolant flow path 62 below the center position CH. Also, the cross-sectional areas of the respective coolant flow paths 70 inside the stator are equal. Therefore, the total value of the cross-sectional areas of the coolant flow paths 70 inside the stator connected to the annular coolant flow path 62 above the center position CH is larger than the total value of the cross-sectional areas of the coolant flow paths 70 inside the stator connected to the annular coolant flow path 62 below the center position CH. When there is a coolant flow path 70c inside the stator provided at the center position CH as shown in FIG. 13, the cross-sectional area is distributed according to the ratio between the upper side and the lower side of the center position CH to calculate the above total value.

[0049] During the operation of the motor of Embodiment 6, coolant also flows through the coolant flow paths 70 inside the stator in addition to the coolant discharge flow path 68. In Embodiment 6, due to the influence of gravity, the pressure in the annular coolant flow path 62 is higher below the center position CH than above the center position CH. Similar to Embodiment 5, the imbalance of the coolant flowing through the coolant discharge flow path 68 is suppressed between the upper side and the lower side of the center position CH, and the coil end 42a is cooled uniformly. Also, in Embodiment 6, the total value of the cross-sectional areas of the coolant flow paths 70 inside the stator above the center position CH is larger than the total value of the cross-sectional areas of the coolant flow paths 70 inside the stator below the center position CH. That is, the overall flow path resistance of the coolant flow paths 70 inside the stator above the center position CH is smaller than the overall flow path resistance of the coolant flow paths 70 inside the stator below the center position CH. For this reason, even if there is a pressure difference between above the center position CH and below the center position CH, it is difficult for a difference to occur between the flow rate of the coolant flowing through the coolant flow paths 70 inside the stator above the center position CH and the flow rate of the coolant flowing through the coolant flow paths 70 inside the stator below the center position CH. For this reason, according to Embodiment 6, the stator core 32 can be cooled uniformly.

Embodiment

[0050] In Example 7, the arrangement and cross-sectional area of the coolant discharge flow path 68 are different from those in Example 5. Other configurations of Example 7 are the same as those of Example 5.

[0051] As shown in FIG. 14, in Example 7, the coolant discharge flow paths 68 are provided at equal angular intervals throughout the circumferential direction of the annular coolant flow path 62. For this reason, the number of coolant discharge flow paths 68 connected to the annular coolant flow path 62 above the center position CH is equal to the number of coolant discharge flow paths 68 connected to the annular coolant flow path 62 below the center position CH. In Example 7, the cross-sectional area of each coolant discharge flow path 68a located above the center position CH is larger than the cross-sectional area of each coolant discharge flow path 68b located below the center position CH. For this reason, the total value of the cross-sectional areas of the coolant discharge flow paths 68 connected to the annular coolant flow path 62 above the center position CH is larger than the total value of the cross-sectional areas of the coolant discharge flow paths 68 connected to the annular coolant flow path 62 below the center position CH. The flow resistance of each coolant discharge flow path 68a is smaller than the flow resistance of each coolant discharge flow path 68b.

[0052] When the motor of Example 7 is in operation, the coolant in the annular coolant flow path 62 is discharged from each coolant discharge flow path 68 toward the coil end 42a. In Example 7, since no partitioning structure is provided in the annular coolant flow path 62, the pressure in the annular coolant flow path 62 is higher below the center position CH than above the center position CH due to the influence of gravity. However, since the flow resistance of the coolant discharge flow path 68a located above the center position CH is smaller than the flow resistance of the coolant discharge flow path 68b located below the center position CH, even if there is a pressure difference between above and below the center position CH, it is difficult for a difference to occur between the flow rate of the coolant discharged to the coil end 42a above the center position CH and the flow rate of the coolant discharged to the coil end 42a below the center position CH. For this reason, according to Example 7, the coil end 42a can be cooled uniformly.

Example

[0053] As shown in FIG. 15, in Example 8, the motor has a coolant flow path 70 in the stator in addition to the coolant discharge flow path 68. Other configurations of Example 8 are the same as those of Example 7. Each coolant flow path 70 in the stator axially penetrates the stator core 32, similar to Example 4 (i.e., FIG. 9). As shown in FIG. 15, the upstream end of each coolant flow path 70 in the stator is connected to the annular coolant flow path 62.

[0054] In Example 8, the coolant flow paths 70 in the stator are provided at equal angular intervals throughout the circumferential direction of the annular coolant flow path 62. Therefore, the number of coolant flow paths 70 in the stator connected to the annular coolant flow path 62 above the center position CH is equal to the number of coolant flow paths 70 in the stator connected to the annular coolant flow path 62 below the center position CH. Also, in Example 8, the cross-sectional area of each coolant flow path 70a in the stator located above the center position CH is larger than the cross-sectional area of each coolant flow path 70b in the stator located below the center position CH. Therefore, the total value of the cross-sectional areas of the coolant flow paths 70 in the stator connected to the annular coolant flow path 62 above the center position CH is larger than the total value of the cross-sectional areas of the coolant flow paths 70 in the stator connected to the annular coolant flow path 62 below the center position CH. The flow resistance of each coolant flow path 70a in the stator is smaller than the flow resistance of each coolant flow path 70b in the stator.

[0055] When the motor of Example 8 is operating, in addition to the coolant discharge passage 68, coolant also flows through the coolant passage 70 in the stator. In Example 8, due to the influence of gravity, the pressure in the annular coolant passage 62 is higher below the center position CH than above the center position CH. Similar to Example 7, the imbalance of the coolant flowing through the coolant discharge passage 68 between the upper and lower sides of the center position CH is suppressed, and the coil end 42a is cooled uniformly. Also, in Example 8, since the flow resistance of the coolant passage 70a in the stator located above the center position CH is smaller than the flow resistance of the coolant passage 70b in the stator located below the center position CH, even if there is a pressure difference between the upper side and the lower side of the center position CH, it is difficult for a difference to occur between the flow rate of the coolant flowing through the coolant passage 70 in the stator located above the center position CH and the flow rate of the coolant flowing through the coolant passage 70 in the stator located below the center position CH. Therefore, according to Example 8, the stator core 32 can be cooled uniformly.

[0056] In Example 8, a difference in cross-sectional area was provided throughout the flow direction of the coolant passage 70 in the stator. However, the flow resistance of the coolant passage 70 in the stator may be adjusted by providing a throttle portion in a part of the coolant passage 70 in the stator. For example, as shown in FIG. 16, by providing a throttle portion 70x with a small cross-sectional area at the downstream end of the coolant passage 70b in the stator below the center position, the flow resistance of the lower coolant passage 70b in the stator may be made larger than the flow resistance of the upper coolant passage 70a in the stator.

[0057] In each of the above-described embodiments, the annular coolant passage 62 was provided inside the guide ring 60. However, as shown in FIG. 17, the guide ring 60 may not have a passage inside, and the annular coolant passage 62 may be formed by the outer peripheral surface of the guide ring 60, the inner surface of the case 50, and the end face 32a of the stator core 32.

[0058] Although the embodiments have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes to the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical utility either alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Also, the technology illustrated in this specification or the drawings achieves multiple purposes simultaneously, and achieving one of those purposes itself has technical utility.

Explanation of Reference Numerals

[0059] 10: Motor 32: Stator Core 42a: Coil End 60: Guide Ring 62: Annular Coolant Flow Path 62a: Upper Flow Path 62b: Lower Flow Path 64a, 64b: Partition Wall 66: Coolant Supply Flow Path 68: Coolant Discharge Flow Path

Claims

1. A motor, comprising: a stator arranged such that a central axis intersects with the vertical direction; an annular coolant flow path provided along an end face of the stator and having an annular shape extending around the central axis; a plurality of individual flow paths each connected to the annular coolant flow path and through which the coolant supplied from the annular coolant flow path flows; and having: the annular coolant flow path having a partition structure that divides the annular coolant flow path into an upper flow path and a lower flow path located below the upper flow path; the plurality of individual flow paths including a plurality of upper individual flow paths connected to the upper flow path and a plurality of lower individual flow paths connected to the lower flow path; a motor.

2. The partition structure is a partition wall that separates the upper flow path from the lower flow path, and further includes an upper coolant supply flow path for supplying coolant to the upper flow path and a lower coolant supply flow path for supplying coolant to the lower flow path. The motor according to claim 1. The motor according to claim 1.

3. The partition structure is a partial partition wall that reduces a cross section of the annular coolant flow path, and further includes a coolant supply flow path for supplying coolant to the upper flow path. The motor according to claim 1. The motor according to claim 1.

4. The partition structure is a check valve that allows the flow of coolant from the upper flow path to the lower flow path and blocks the flow of coolant from the lower flow path to the upper flow path, and further includes a coolant supply flow path for supplying coolant to the upper flow path. The motor according to claim 1. The motor according to claim 1.

5. Further including a coil wound around the stator and having a coil end disposed at an inner peripheral portion of the annular coolant flow path, and the plurality of individual flow paths having a plurality of coolant discharge flow paths that discharge coolant toward the coil end. The motor according to any one of claims 1 to 4. The motor according to any one of claims 1 to 4.

6. The plurality of individual flow paths have a plurality of stator internal coolant flow paths provided inside the stator. The motor according to any one of claims 1 to 4. The motor according to any one of claims 1 to 4.

7. A motor, comprising: a stator arranged such that a central axis intersects with the vertical direction; an annular coolant flow path provided along an end face of the stator and having an annular shape extending around the central axis; a coil wound around the stator and having a coil end disposed at an inner peripheral portion of the annular coolant flow path; ​ ​ ​ ​ A plurality of coolant discharge channels, each of which is connected to the annular coolant flow path and discharges the coolant supplied from the annular coolant flow path toward the coil end, having, wherein a total value of cross-sectional areas of the coolant discharge channels connected to the annular coolant flow path above a central position in the vertical direction of the annular coolant flow path is larger than a total value of cross-sectional areas of the coolant discharge channels connected to the annular coolant flow path below the central position, a motor. **Claim 8** further comprising a plurality of coolant flow channels inside the stator, each of which is provided inside the stator, each of which is connected to the annular coolant flow path, and through which the coolant supplied from the annular coolant flow path flows, wherein a total value of cross-sectional areas of the coolant flow channels inside the stator connected to the annular coolant flow path above the central position is larger than a total value of cross-sectional areas of the coolant flow channels inside the stator connected to the annular coolant flow path below the central position, The motor according to claim 7.

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