Vehicle drive device

Abstract

This vehicle drive device comprises: a rotary electric machine that includes a stator having a stator core; a resin tube member that covers at least the outer peripheral surface of the stator core; and a case that accommodates the rotary electric machine and the tube member. A refrigerant flow path through which a refrigerant for cooling the stator core flows is formed between the tube member and the case.

Description

Vehicle drive unit

[0001] The present invention relates to a vehicle drive device.

[0002] A rotating electric machine having a coolant passage through which a coolant for cooling a stator core flows is known. Such a rotating electric machine is disclosed, for example, in International Publication No. 2020 / 213052.

[0003] International Publication No. 2020 / 213052 discloses a rotating electric machine having a coolant flow path (refrigerant flow path) formed therein through which a coolant (refrigerant) for cooling a stator core flows. In the rotating electric machine described in International Publication No. 2020 / 213052, a rotor and a stator including a stator core are housed in a housing (case). The housing has a double-wall structure consisting of an inner housing and an outer housing to form a coolant flow path inside the housing through which a coolant for cooling the stator core flows.

[0004] International Publication No. 2020 / 213052

[0005] However, in WO 2020 / 213052, the housing (case) has a double-wall structure consisting of an inner housing and an outer housing to form a coolant flow path (refrigerant flow path), which makes the housing relatively large and the structure of the housing relatively complex. Therefore, there is a need for a configuration that can form a coolant flow path (refrigerant flow path) through which a coolant (refrigerant) for cooling a stator core flows while preventing the housing (case) from becoming large and the housing structure from becoming complex.

[0006] This invention has been made to solve the above-mentioned problems, and one object of the invention is to provide a vehicle drive device that is capable of forming a refrigerant flow path through which a refrigerant for cooling a stator core flows, while preventing the case from becoming larger and the case structure from becoming more complex.

[0007] In order to achieve the above object, a vehicle drive device in one aspect of the present invention includes a rotating electric machine that includes a rotor, a stator that is arranged opposite the outer peripheral surface of the rotor and has a stator core, and functions as a driving force source for a wheel, a resin tube member that covers at least the outer peripheral surface of the stator core, and a case that houses the rotating electric machine and the tube member, and a refrigerant flow path is formed between the tube member and the case through which a refrigerant flows to cool the stator core.

[0008] According to one aspect of the present invention, a vehicle drive device includes a rotating electric machine including a stator having a stator core, a resin tube member covering at least an outer peripheral surface of the stator core, and a case accommodating the rotating electric machine and the tube member. A refrigerant flow path through which a refrigerant for cooling the stator core flows is formed between the tube member and the case. Since the outer peripheral surface of the stator core and the refrigerant flow path are adjacent to each other via the resin tube member, the refrigerant flow path can be formed without requiring the case to have a double-wall structure. As a result, the refrigerant flow path through which a refrigerant for cooling the stator core flows can be formed while preventing the case from becoming large and the case structure from becoming complicated. Resin tube members generally do not allow liquids to pass through them, even when they have a very thin thickness (e.g., on the order of microns). Therefore, even if the tube member is made of a resin having a thermal conductivity significantly lower than that of metal, the stator core can be sufficiently cooled by the refrigerant flowing through the refrigerant flow path by using a resin tube member having a very thin thickness (e.g., on the order of microns).

[0009] In the vehicle drive device according to the aforementioned aspect, the tube member preferably covers at least one of one axial end face and the other axial end face of the stator core in addition to the outer peripheral surface of the stator core.

[0010] With this configuration, the sealing performance between the stator core and the refrigerant flow path provided by the tube member can be improved compared to when the tube member covers only the outer peripheral surface of the stator core.

[0011] In the configuration in which the tube member covers not only the outer peripheral surface of the stator core but also at least one of the end faces on one axial side and the other axial side of the stator core, preferably the tube member covers not only the outer peripheral surface of the stator core but also the end face on one axial side of the stator core, and further includes a sealing member that seals between the case and the one-side covering portion of the tube member that covers the end face on one axial side of the stator core.

[0012] With this configuration, the sealing member seals between the case and the one-side covering portion of the tube member that covers one axial end face of the stator core, thereby further improving the sealing performance between the stator core and the refrigerant flow path provided by the tube member.

[0013] In the vehicle drive device according to the aforementioned aspect, the tube member is preferably a heat-shrinkable tube member.

[0014] With this configuration, by applying heat to the tube member to shrink the tube member, the tube member can be brought into close contact with at least the outer peripheral surface of the stator core, which improves the cooling performance of the refrigerant through the tube member covering the outer peripheral surface of the stator core compared to when the tube member is not heat-shrinkable.

[0015] In the present application, the vehicle drive device according to the above aspect may also have the following configuration.

[0016] (Additional Item 1) In the vehicle drive device according to the above aspect, preferably, the stator core includes a fastening protrusion portion that protrudes toward the outer periphery and has a core through hole through which a fastening member for fixing the stator core to the case passes, and the tube member covers the outer periphery of the stator core, including the outer periphery of the fastening protrusion portion.

[0017] By configuring it in this manner, it is possible to form a refrigerant flow path through which a refrigerant flows to cool the stator core including the fastening protrusion portion, while preventing the case from becoming larger and the case structure from becoming more complex.

[0018] (Additional Item 2) In a configuration including a sealing member that seals between the case and one side covering portion of the tube member, preferably, a first sealing member groove for arranging the sealing member is formed in the portion of the case facing the one side covering portion of the tube member, and an O-ring as a sealing member is arranged in the first sealing member groove.

[0019] With this configuration, the O-ring as the seal member disposed in the first seal member groove can easily seal the gap between the case and one side cover portion of the tube member.

[0020] (Additional Item 3) In a configuration including a sealing member that seals between the case and one side covering portion of the tube member, preferably, the tube member covers the outer peripheral surface of the stator core, one axial end face of the stator core, and the other axial end face of the stator core, and in the space including the refrigerant flow path between the case and the tube member, a lip seal member formed by vulcanization welding a resin member with a tongue-shaped tip to a metal plate member is arranged in a portion facing the one axial end face of the tube member that covers the one axial end face of the stator core.

[0021] With this configuration, the lip seal member, which serves as a seal member facing the one-side covering portion of the tube member in the space including the refrigerant flow path between the case and the tube member, can easily seal the gap between the case and the one-side covering portion of the tube member. In this case, there is no need to form a groove for the seal member in the case, which simplifies the manufacturing process of the case.

[0022] (Additional Item 4) In a configuration including a sealing member that seals between the case and one side covering portion of the tube member, preferably, the configuration further includes an annular plate-shaped member that is arranged on the other axial end face side of the stator core and forms a refrigerant flow path together with the tube member and the case, and a second sealing member groove for arranging the sealing member is formed in a portion of the plate-shaped member that faces the other axial covering portion that covers the other axial end face of the tube member, and a third sealing member groove for arranging the sealing member is formed in a portion of the plate-shaped member that faces the case, and a second O-ring and a third O-ring are arranged as sealing members in the second sealing member groove and the third sealing member groove, respectively.

[0023] With this configuration, the second O-ring as a seal member disposed in the second seal member groove can easily seal between the plate-like member and the other side covering portion of the tube member, and the third O-ring as a seal member disposed in the third seal member groove can easily seal between the plate-like member and the case.

[0024] (Additional Item 5) In the vehicle drive device according to the above aspect, preferably, the device further includes an annular plate-shaped member that is arranged on the other axial end face side of the stator core, has a fastening through hole through which a fastening member for fixing the stator core to the case passes, and forms a refrigerant flow path together with the tube member and the case, and the stator core is fixed to the case by being fastened to the case by the fastening member, with the plate-shaped member arranged on the other axial end face side of the stator core so as to form a refrigerant flow path.

[0025] With this configuration, the stator core can be easily fixed to the case by the annular plate-shaped member arranged on the other axial end face of the stator core, while forming a refrigerant flow path together with the tube member and the case. Furthermore, because the stator core is fixed to the case by fastening it to the case with the fastening member, compressive stress is not applied to the stator core compared to when the stator core is fixed to the case by shrink fitting. Therefore, an increase in iron loss (energy loss) due to compressive stress applied to the stator core during rotor rotation can be suppressed, thereby suppressing a decrease in electric fuel efficiency.

[0026] According to the present invention, as described above, a vehicle drive device can be provided that is capable of forming a refrigerant flow path through which a refrigerant for cooling a stator core flows, while preventing the case from becoming larger and the case structure from becoming more complex.

[0027] Fig. 1 is a cross-sectional view showing a vehicle drive device according to a first embodiment of the present invention. Fig. 1 is a cross-sectional view taken along line 920-920 in Fig. 1. Fig. 1 is an enlarged cross-sectional view of the periphery of a cooling water flow path in Fig. 1. Fig. 1 is a cross-sectional view taken along line 930-930 in Fig. 1. Fig. 2 is an enlarged cross-sectional view of the periphery of a cooling water flow path in a vehicle drive device according to a second embodiment of the present invention. Fig. 3 is an enlarged cross-sectional view of the periphery of a cooling water flow path in a vehicle drive device according to a modified example of the present invention.

[0028] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0029] 1 to 4, the configuration of a vehicle drive device 100 according to a first embodiment of the present invention will be described. The vehicle drive device 100 is a drive device used in, for example, an electric vehicle, a hybrid vehicle, or the like.

[0030] 1, the vehicle drive device 100 includes a rotating electric machine RE including a rotor 10 and a stator 20, a tube member 30, a case 40, and a plate-shaped member 50. The rotating electric machine RE is, for example, a motor, a generator, or a motor / generator combination. The rotating electric machine RE functions as a driving force source for the wheels.

[0031] In the following description, the axial, radial, and circumferential directions of the rotor 10 (see FIG. 1) and the stator 20 (see FIG. 1) of the rotating electric machine RE are referred to as the Z direction, the R direction, and the C direction, respectively. Furthermore, one side and the other side in the axial direction (Z direction) are referred to as the Z1 side and the Z2 side, respectively. Furthermore, the inside (inner peripheral side) and outside (outer peripheral side) in the radial direction (R direction) are referred to as the R1 side and the R2 side, respectively.

[0032] <Configuration of the rotor> As shown in Fig. 1, the rotor 10 has a rotor core 11 and a rotor shaft 12. The rotor core 11 is formed in an annular shape. The rotor core 11 is formed by laminating a plurality of electromagnetic steel plates. When viewed from the Z direction, a shaft insertion hole 11a extending in the Z direction is formed in the center of the rotor core 11. The rotor shaft 12 is fixed to the rotor core 11 in a state where it is inserted into the shaft insertion hole 11a. The rotor 10 and the rotor shaft 12 are configured to be rotatable about a central axis 910 that lies along the Z direction.

[0033] <Configuration of Stator> As shown in Fig. 1 , the stator 20 is disposed on the R2 side of the rotor 10 (rotor core 11) so as to face the outer peripheral surface 10a of the rotor 10. That is, the rotating electric machine RE is an inner rotor type rotating electric machine. The stator 20 has a stator core 21 and a coil (not shown). The stator core 21 is formed in an annular shape. The stator core 21 is formed by laminating multiple electromagnetic steel plates. The coil (not shown) is wound around the stator core 21.

[0034] As shown in Fig. 2, the stator core 21 includes a fastening protrusion 21a that protrudes toward the outer periphery (R2 side). A core through hole 21b is formed in the fastening protrusion 21a. As shown in Fig. 1, a fastening member 60 for fixing the stator core 21 to the case 40 passes through the core through hole 21b. Note that Fig. 1 shows an example in which the fastening member 60 is a bolt.

[0035] 3, the tube member 30 covers not only the outer peripheral surface 21c of the stator core 21, but also an end face 21d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21 (Z1 side) and an end face 21e on the other side (Z2 side). Specifically, the tube member 30 covers the entire outer peripheral surface 21c of the stator core 21, including the outer peripheral surfaces of the fastening protrusions 21a. The tube member 30 also covers a portion of the Z1-side end face 21d of the stator core 21 on the R2 side. The tube member 30 also covers a portion of the Z2-side end face 21e of the stator core 21 on the R2 side.

[0036] The tube member 30 is made of resin. The tube member 30 is a heat-shrinkable tube member. The tube member 30 preferably has a continuous use temperature (long-term heat resistance temperature) of 200°C or higher. The tube member 30 has a thickness of at least less than 1000 μm, and preferably has a thickness of 20 μm or more and 500 μm or less. The tube member 30 is made of, for example, fluororesin PFA (Per Fluoro Alkoxy Polymer) or fluororesin FEP (Fluorinated Ethylene Propylene).

[0037] <Configuration of the Case> As shown in FIG. 1 , the case 40 houses the rotating electric machine RE and the tube member 30. The case 40 is made of a metal such as aluminum. A coolant flow path 70 is formed between the tube member 30 and the case 40. Specifically, as shown in FIG. 3 , the coolant flow path 70 is formed between an outer peripheral surface covering portion 31 of the tube member 30 that covers the outer peripheral surface 21 c of the stator core 21 and a tube member facing portion 41 of the case 40 that faces the outer peripheral surface covering portion 31 of the tube member 30 in the R direction. Coolant for cooling the stator core 21 flows through the coolant flow path 70. The coolant is, for example, a liquid containing a component with an antifreeze effect. The coolant flow path 70 and the coolant are examples of a "refrigerant flow path" and a "refrigerant," respectively, as defined in the claims.

[0038] 2, the cooling water flow path 70 is formed in an annular shape. In the C direction, a width W1 of a portion of the cooling water flow path 70 where the fastening protrusion 21 a of the stator core 21 is present is smaller than a width W2 of a portion of the cooling water flow path 70 where the fastening protrusion 21 a of the stator core 21 is not present.

[0039] <Configuration of Plate-Shaped Member> As shown in FIG. 1 , the plate-shaped member 50 is disposed on the end face 21e of the stator core 21 on the other side (Z2 side) in the axial direction (Z direction). As shown in FIG. 4 , the plate-shaped member 50 is formed in an annular shape. As shown in FIG. 3 , the plate-shaped member 50, together with the tube members 30 and the case 40, forms a coolant flow path 70. Specifically, the plate-shaped member 50 contacts the other-side cover portion 32 of the tube members 30 that covers the end face 21e of the stator core 21 on the Z2 side, and the portion of the Z2-side end face 21e of the stator core 21 that is not covered by the tube members 30. The plate-shaped member 50 is formed to extend in the R direction. An R2-side end 51 of the plate-shaped member 50 contacts the case 40. That is, the Z2-side end of the coolant flow path 70 formed by the outer peripheral surface cover portion 31 of the tube members 30 and the tube member-facing portion 41 of the case 40 is blocked by the plate-shaped member 50. The Z1 side end of the cooling water flow path 70 formed by the outer peripheral surface covering portion 31 of the tube member 30 and the tube member opposing portion 41 of the case 40 is blocked by the one side covering portion 33 of the tube member 30, which covers the Z1 side end face 21d of the stator core 21, coming into contact with the surface 42 of the case 40 extending along the RC plane.

[0040] The plate-shaped member 50 has fastening through-holes 52 through which fastening members 60 for fixing the stator core 21 to the case 40 pass. The stator core 21 is fixed to the case 40 by fastening the plate-shaped member 50 to the case 40 with the fastening members 60, with the plate-shaped member 50 arranged on an end face 21 e on the other side (Z2 side) in the axial direction (Z direction) of the stator core 21 so as to form a cooling water flow path 70. Specifically, a fastening hole 44 into which a tip end of the fastening member 60 is inserted is formed in a portion 43 of the case 40 arranged on the Z1 side of the stator core 21, which has a surface 42 extending along the RC plane. The fastening hole 44 has a female thread formed therein that engages with a male thread formed on the tip end of the fastening member 60. Then, as viewed from the Z direction, the portion 43 of the case 40, the stator core 21, and the plate-shaped member 50 are aligned in this order from the Z1 side to the Z2 side so that the fastening hole 44 of the case 40, the core through hole 21b of the stator core 21, and the fastening through hole 52 of the plate-shaped member 50 overlap. Then, the fastening member 60 is passed through the fastening through hole 52 of the plate-shaped member 50 and the core through hole 21b of the stator core 21 from the Z2 side of the plate-shaped member 50. Then, the male thread formed at the tip of the fastening member 60 is engaged with the female thread formed in the fastening hole 44 of the case 40.

[0041] 3, the vehicle drive device 100 includes a seal member that seals between the case 40 and the one side cover portion 33 of the tube member 30. Specifically, a first seal member groove 45 for arranging the seal member is formed in a portion of the case 40 that faces the one side cover portion 33. A first O-ring 81 serving as a seal member is arranged in the first seal member groove 45.

[0042] The vehicle drive device 100 includes a seal member that seals between the plate-shaped member 50 and the other-side cover portion 32 of the tube member 30. Specifically, a second seal member groove 53 for arranging the seal member is formed in a portion of the plate-shaped member 50 that faces the other-side cover portion 32 of the tube member 30. A second O-ring 82 serving as a seal member is arranged in the second seal member groove 53.

[0043] The vehicle drive device 100 includes a seal member that seals between the plate-shaped member 50 and the case 40. Specifically, a third seal member groove 54 for arranging the seal member is formed in a portion of the plate-shaped member 50 that faces the case 40 (a portion of the plate-shaped member 50 that comes into contact with the case 40). A third O-ring 83 serving as a seal member is arranged in the third seal member groove 54.

[0044] (Effects of First Embodiment) In the first embodiment, the following effects can be obtained.

[0045] In the first embodiment, the vehicle drive device 100 includes a rotating electric machine RE including a stator 20 having a stator core 21, a resin tube member 30 covering at least an outer peripheral surface 21 c of the stator core 21, and a case 40 accommodating the rotating electric machine RE and the tube member 30. A coolant flow path 70 through which coolant for cooling the stator core 21 flows is formed between the tube member 30 and the case 40. Since the outer peripheral surface 21 c of the stator core 21 and the coolant flow path 70 are adjacent to each other via the resin tube member 30, the coolant flow path 70 can be formed without making the case 40 a double-wall structure. As a result, the coolant flow path 70 through which coolant for cooling the stator core 21 flows can be formed while preventing the case 40 from becoming large and the structure of the case 40 from becoming complicated. The resin tube member 30 is generally impermeable to liquids even when it has a very thin thickness (for example, on the order of μm). Therefore, even if the tube member 30 is made of resin, which has a very low thermal conductivity compared to metal, by using a resin tube member 30 with a very thin thickness (for example, on the order of μm), the stator core 21 can be sufficiently cooled by the cooling water flowing through the cooling water flow path 70.

[0046] Furthermore, in the first embodiment, the tube member 30 covers not only the outer peripheral surface 21c of the stator core 21, but also an end face 21d on one side (Z1 side) and an end face 21e on the other side (Z2 side) in the axial direction (Z direction) of the stator core 21. This improves the sealing performance between the stator core 21 and the coolant flow path 70 provided by the tube member 30 compared to a case where the tube member 30 covers only the outer peripheral surface 21c of the stator core 21.

[0047] Furthermore, in the first embodiment, the vehicle drive device 100 includes a seal member (first O-ring 81) that seals between the case 40 and one side cover portion 33 of the tube member 30 that covers the end face 21 d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21. This allows the seal member (first O-ring 81) to seal between the case 40 and the one side cover portion 33 of the tube member 30 that covers the end face 21 d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21, thereby further improving the sealing performance between the stator core 21 and the coolant flow path 70 by the tube member 30.

[0048] In the first embodiment, the tube member 30 is a heat-shrinkable tube member. By applying heat to the tube member 30 to shrink the tube member 30, the tube member 30 can be brought into close contact with at least the outer peripheral surface 21 c of the stator core 21. As a result, the cooling performance of the coolant passing through the tube member 30 that covers the outer peripheral surface 21 c of the stator core 21 can be improved compared to when the tube member 30 is not heat-shrinkable.

[0049] In the first embodiment, the stator core 21 includes a core through-hole 21b through which a fastening member 60 for fixing the stator core 21 to the case 40 passes and a fastening protrusion 21a protruding outward (toward the R2 side). The tube member 30 covers the outer peripheral surface 21c of the stator core 21, including the outer peripheral surface of the fastening protrusion 21a. This makes it possible to form a cooling water flow path 70 through which cooling water flows for cooling the stator core 21, including the fastening protrusion 21a, while preventing the case 40 from becoming larger and the structure of the case 40 from becoming complicated.

[0050] In the first embodiment, a first seal groove 45 for disposing a seal member is formed in a portion of the case 40 facing the one side cover portion 33 of the tube member 30. A first O-ring 81 serving as a seal member is disposed in the first seal groove 45. This allows the first O-ring 81 serving as a seal member disposed in the first seal groove 45 to easily seal the gap between the case 40 and the one side cover portion 33 of the tube member 30.

[0051] In the first embodiment, the vehicle drive device 100 includes an annular plate-shaped member 50 disposed on the other end face 21e (Z2 side) of the stator core 21 in the axial direction (Z direction) and forming a coolant flow path 70 together with the tube member 30 and the case 40. A second seal groove 53 for disposing a seal member is formed in a portion of the plate-shaped member 50 facing the other-side cover portion 32 that covers the other end face 21e (Z2 side) of the tube member 30 in the axial direction (Z direction). A third seal groove 54 for disposing a seal member is formed in a portion of the plate-shaped member 50 facing the case 40. A second O-ring 82 and a third O-ring 83 serving as seal members are disposed in the second seal groove 53 and the third seal groove 54, respectively. This allows the second O-ring 82 serving as a seal member disposed in the second seal groove 53 to easily seal the gap between the plate-shaped member 50 and the other-side cover portion 32 of the tube member 30. Furthermore, the third O-ring 83 as a seal member disposed in the third seal member groove 54 can easily seal the gap between the plate-like member 50 and the case 40 .

[0052] Furthermore, in the first embodiment, the vehicle drive device 100 includes an annular plate-shaped member 50 that is disposed on the end face 21 e of the stator core 21 on the other side (Z2 side) in the axial direction (Z direction), has fastening through holes 52 through which fastening members 60 for fixing the stator core 21 to the case 40 pass, and forms a coolant flow path 70 together with the tube members 30 and the case 40. The stator core 21 is fixed to the case 40 by fastening the plate-shaped member 50 to the case 40 with the fastening members 60 in a state in which the plate-shaped member 50 is disposed on the end face 21 e of the stator core 21 on the other side (Z2 side) in the axial direction (Z direction) so as to form the coolant flow path 70. This makes it possible to easily fix the stator core 21 to the case 40 by the annular plate-shaped member 50 that is disposed on the end face 21 e of the stator core 21 on the other side (Z2 side) in the axial direction (Z direction), while forming the coolant flow path 70 together with the tube members 30 and the case 40. Furthermore, because stator core 21 is fixed to case 40 by being fastened to case 40 with fastening members 60, compressive stress is not applied to stator core 21 compared to when stator core 21 is fixed to case 40 by being shrink-fitted to case 40. Therefore, when rotor 10 rotates, an increase in iron loss (energy loss) due to compressive stress applied to stator core 21 can be suppressed, and a decrease in electricity consumption can be suppressed.

[0053] Second Embodiment The configuration of a vehicle drive device 200 according to a second embodiment of the present invention will be described with reference to Fig. 5. In the figure, the same components as those in the first embodiment are denoted by the same reference numerals.

[0054] (Overall Configuration of Vehicle Drive Device) As shown in FIG. 5 , the vehicle drive device 200 includes a rotating electric machine RE including a rotor 10 and a stator 20 , a tube member 30 , a case 240 , and a plate-like member 50 .

[0055] As in the first embodiment described above, the tube member 30 covers not only the outer peripheral surface 21c of the stator core 21, but also the end face 21d on one side (Z1 side) and the end face 21e on the other side (Z2 side) of the axial direction (Z direction) of the stator core 21.

[0056] As in the first embodiment, the case 240 houses the rotor 10 and the stator 20. As in the first embodiment, a cooling water flow path 70 is formed between the tube member 30 and the case 240. Cooling water for cooling the stator core 21 flows through the cooling water flow path 70.

[0057] (Sealing structure of cooling water flow path) In the space including the cooling water flow path 70 between the case 240 and the tube member 30, a lip seal member 280, which is a sealing member and is made of a resin member having a tongue-shaped tip portion vulcanization-welded to a metal plate-like member, is disposed in a portion facing the one-side cover portion 33 of the tube member 30 that covers the end face 21 d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21. Note that, because a space is required for disposing the lip seal member 280 in the portion facing the one-side cover portion 33 of the tube member 30, an end face 242 on the Z1 side of the space including the cooling water flow path 70 between the case 240 and the tube member 30 is separated from the end face 21 d on the Z1 side of the stator core 21.

[0058] The other configurations of the vehicle drive device 200 of the second embodiment are similar to those of the vehicle drive device 100 of the first embodiment.

[0059] (Effects of Second Embodiment) In the second embodiment, the following effects can be obtained.

[0060] In the second embodiment, a vehicle drive device 200 includes a rotating electric machine RE including a stator 20 having a stator core 21, a resin tube member 30 covering at least an outer peripheral surface 21 c of the stator core 21, and a case 240 accommodating the rotating electric machine RE and the tube member 30. A coolant flow path 70 through which coolant for cooling the stator core 21 flows is formed between the tube member 30 and the case 240. As a result, similar to the first embodiment, the outer peripheral surface 21 c of the stator core 21 and the coolant flow path 70 are adjacent to each other via the resin tube member 30, so that the coolant flow path 70 can be formed without making the case 240 a double-wall structure. As a result, similar to the first embodiment, the coolant flow path 70 through which coolant for cooling the stator core 21 flows can be formed while preventing the case 240 from becoming large and the structure of the case 240 from becoming complex.

[0061] Furthermore, in the second embodiment, as described above, a lip seal member 280, which is formed by vulcanization welding a resin member having a tongue-shaped tip to a metal plate-like member, is disposed in a portion of the tube member 30 facing the one side cover portion 33 that covers the end face 21d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21 in the space including the coolant flow path 70 between the case 240 and the tube member 30. This makes it possible to easily seal between the case 240 and the one side cover portion 33 of the tube member 30 by the lip seal member 280, which serves as a seal member disposed in a portion facing the one side cover portion 33 of the tube member 30 in the space including the coolant flow path 70 between the case 240 and the tube member 30. In this case, there is no need to form a groove for disposing a seal member in the case 240, and therefore the manufacturing process of the case 240 can be simplified.

[0062] The other effects of the second embodiment are the same as those of the first embodiment.

[0063] [Modifications] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above-mentioned embodiments, and further includes all modifications (modifications) within the meaning and scope of the claims.

[0064] For example, in the above first and second embodiments, an example was shown in which the vehicle drive device 100 (200) is arranged on the end face 21e side (Z2 side) of the stator core 21 in the axial direction (Z direction), has fastening through holes 52 through which fastening members 60 for fixing the stator core 21 to the case 40 (240), and includes an annular plate-shaped member 50 that forms the cooling water flow path 70 together with the tube member 30 and the case 40 (240), and the stator core 21 is fixed to the case 40 (240) by being fastened to the case 40 (240) with the fastening members 60, with the plate-shaped member 50 arranged on the end face 21e side (Z2 side) of the stator core 21 in the axial direction (Z direction) so as to form the cooling water flow path 70, but the present invention is not limited to this. In the present invention, as in a modified example shown in Fig. 6 , the vehicle drive device 300 does not include the annular plate-like member 50 like the vehicle drive device 100 (200), and the stator core 21 may be fixed to the case 240 without being fastened to the case 240 by the fastening member 60. As shown in Fig. 6 , the vehicle drive device 300 includes a seal member 381 arranged near the Z1-side end of the coolant flow path 70 formed by the outer circumferential surface covering portion 31 of the tube member 30 and the tube member-facing portion 41 of the case 240, and a seal member 382 arranged at the Z2-side end of the coolant flow path 70 formed by the outer circumferential surface covering portion 31 of the tube member 30 and the tube member-facing portion 41 of the case 240.

[0065] In addition, in the above first and second embodiments, the vehicle drive device 100 (200) is provided with an annular plate-shaped member 50 that is arranged on the end face 21e side (Z2 side) of the stator core 21 in the axial direction (Z direction) and forms the coolant flow path 70 together with the tube member 30 and the case 40 (240), and a second seal member groove 53 for arranging a seal member is formed in a portion of the plate-shaped member 50 that faces the other-side cover portion 32 that covers the end face 21e on the other side (Z2 side) of the tube member 30 in the axial direction (Z direction), and a third seal member groove 54 for arranging a seal member is formed in a portion of the plate-shaped member 50 that faces the case 40 (240), and a second O-ring 82 and a third O-ring 83 are arranged as seal members in the second seal member groove 53 and the third seal member groove 54, respectively. However, the present invention is not limited to this. In the present invention, as in the modified example shown in FIG. 6, the vehicle drive device 300 does not have to include the annular plate-shaped member 50 as in the vehicle drive device 100 (200).

[0066] In the above-described first and second embodiments, the stator core 21 includes the fastening protrusions 21a protruding outward (toward the R2 side) and having the core through-holes 21b through which the fastening members 60 for fixing the stator core 21 to the case 40 (240) pass, and the tube members 30 cover the outer peripheral surface 21c of the stator core 21, including the outer peripheral surfaces of the fastening protrusions 21a. However, the present invention is not limited to this. In the present invention, the stator core 21 may not include the fastening protrusions 21a, and the tube members 30 may cover the outer peripheral surface 21c of the stator core 21 that does not include the fastening protrusions 21a.

[0067] In the first and second embodiments, the tube member 30 is a heat-shrinkable tube member, but the present invention is not limited to this. In the present invention, the tube member 30 may be a tube member that does not have heat-shrinkability.

[0068] Furthermore, in the above-described first and second embodiments, an example was shown in which the vehicle drive device 100 (200) includes a seal member (first O-ring 81) that seals between the case 40 (240) and the one-side cover portion 33 of the tube member 30 that covers the end face 21 d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21, but the present invention is not limited to this. In the present invention, the vehicle drive device 100 (200) does not have to include a seal member (first O-ring 81) that seals between the case 40 (240) and the one-side cover portion 33 of the tube member 30 that covers the end face 21 d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21.

[0069] Furthermore, in the above-described first and second embodiments, an example has been described in which the tube member 30 covers not only the outer peripheral surface 21c of the stator core 21 but also the end face 21d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21 and the end face 21e on the other side (Z2 side) of the stator core 21. However, the present invention is not limited to this. In the present invention, the tube member 30 may cover not only the outer peripheral surface 21c of the stator core 21 but also only one of the end face 21d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21 and the end face 21e on the other side (Z2 side) of the stator core 21. Furthermore, the tube member 30 may cover the outer peripheral surface 21c of the stator core 21 but not the end face 21d on one side (Z1 side) in the axial direction (Z direction) of the stator core 21 and the end face 21e on the other side (Z2 side) of the stator core 21.

[0070] In the first and second embodiments, the "refrigerant" in the claims is cooling water, but the present invention is not limited to this. In the present invention, the "refrigerant" in the claims may be a refrigerant other than cooling water (for example, a refrigerant used in a heating and cooling device).

[0071] 10... rotor, 10a... outer peripheral surface of rotor, 20... stator, 21... stator core, 21c... outer peripheral surface of stator core, 21d... one end face in the axial direction of stator core, 30... tube member, 33... one side cover portion, 40, 240... case, 70... cooling water flow path (refrigerant flow path), 100, 200, 300... vehicle drive device, rotating electric machine... RE

Claims

1. A vehicle drive device comprising: a rotating electric machine including a rotor and a stator having a stator core arranged opposite the outer peripheral surface of the rotor, functioning as a driving force source for wheels; a resin tube member covering at least the outer peripheral surface of the stator core; and a case accommodating the rotating electric machine and the tube member, wherein a refrigerant flow path is formed between the tube member and the case through which a refrigerant for cooling the stator core flows.

2. The vehicle drive device according to claim 1, wherein the tube member covers not only the outer peripheral surface of the stator core but also at least one of an end face on one side and an end face on the other side in the axial direction of the stator core.

3. A vehicle drive device as described in claim 2, wherein the tube member covers, in addition to the outer peripheral surface of the stator core, one axial end face of the stator core, and further includes a sealing member that seals between the case and a one-side covering portion of the tube member that covers the one axial end face of the stator core.

4. The vehicle drive device according to claim 1, wherein the tube member is a heat-shrinkable tube member.

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