Vehicle drive device

Abstract

The invention relates to a vehicle drive device. Disclosed is a drive device for a vehicle, which is provided with: a rotating electrical machine; and a flow path forming member having a cylindrical shape having an inner circumferential surface facing the outer circumferential surface of the rotating electrical machine in the radial direction, and forming a refrigerant flow path around the rotating electrical machine, the refrigerant flow path having: a first circumferential section including a connection portion with respect to the refrigerant supply portion; a second circumferential section including a connection portion with respect to the refrigerant discharge portion; a third circumferential section on one side of two circumferential sections between the first circumferential section and the second circumferential section in the circumferential direction; and a fourth circumferential section on the other side, the flow path forming member having, in the third circumferential section, a protrusion protruding in the radial direction so as to reduce the cross-sectional area of the refrigerant flow path, the axis of the shaft member being parallel to the axis of the rotating electrical machine and being offset in a direction intersecting the axial direction, and the fourth circumferential section being offset in a direction intersecting the axial direction when viewed in the axial direction. A straight line connecting the axis of the shaft member and the axis of the rotating electrical machine is intersected with each other.

Description

Technical Field

[0001] The invention relates to a vehicle driving device. Background Art

[0002] A technique for forming a refrigerant flow path (cooling water path) around a rotating electric machine is known.

[0003] Patent Document 1: U.S. Patent Application Publication No. 2020 / 0235640

[0004] However, in the above-described conventional technology, it is difficult to make the flow of the refrigerant uniform over the entire circumference of the rotating electric machine in the circumferential direction. Summary of the invention

[0005] Therefore, in one aspect, an object of the present invention is to achieve uniformity of the flow of refrigerant throughout the entire circumference around a rotating electrical machine in the circumferential direction.

[0006] In one aspect, a vehicle driving device is provided, comprising:

[0007] Rotating electrical machines;

[0008] The flow path forming member is a cylindrical member having an inner peripheral surface radially opposed to the outer peripheral surface of the rotating electrical machine and forming a refrigerant flow path around the rotating electrical machine;

[0009] A refrigerant supply unit connected to the refrigerant flow path;

[0010] a refrigerant discharge portion connected to the refrigerant flow path; and

[0011] a transmission mechanism that transmits the driving force from the rotating electric machine to the wheels via the shaft member,

[0012] The refrigerant flow path includes: a first circumferential section including a connection portion relative to the refrigerant supply portion; a second circumferential section including a connection portion relative to the refrigerant discharge portion; a third circumferential section on one side of two circumferential sections between the first circumferential section and the second circumferential section in the circumferential direction; and a fourth circumferential section on the other side,

[0013] The flow path forming member has a convex portion protruding in the radial direction in the third circumferential section so as to reduce the cross-sectional area of ​​the refrigerant flow path.

[0014] The axis of the shaft member is parallel to the axis of the rotating electrical machine and is offset in a direction intersecting the axial direction.

[0015] The fourth circumferential section intersects a straight line connecting the shaft member and the axial center of the rotating electrical machine when viewed in the axial direction.

[0016] In one aspect, according to the present invention, it is possible to achieve uniformity of the flow of the refrigerant around the entire circumference of the rotating electric machine in the circumferential direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic plan view showing a state in which a vehicle drive device is mounted on a vehicle.

[0018] Figure 2 It is a cross-sectional view of a vehicle drive device.

[0019] Figure 2A It is a schematic diagram showing a vehicle drive device.

[0020] Figure 3 It is a side view schematically showing the vehicle drive device of this embodiment.

[0021] Figure 4 It is a perspective view of a flow path forming member.

[0022] Figure 4A yes Figure 4 An enlarged view of the Q4 section.

[0023] Figure 5 This is a schematic diagram of a refrigerant flow path formed by flow path forming components.

[0024] Fig. 6A This is a cross-sectional view of a portion of the refrigerant flow path.

[0025] Figure 6B It is a side view schematically showing the positional relationship among the first output member, the refrigerant supply portion, and the refrigerant discharge portion.

[0026] Figure 6C yes Figure 2 An enlarged view of the Q6 section.

[0027] Figure 7 It is an explanatory diagram of a preferred arrangement of the fastening portion and is a side view schematically showing the vehicle drive device of this embodiment.

[0028] Fig. 7A The schematic diagram shows that a portion of the fastening portion of the comparative example is overlapped with the dotted line. Figure 7 Figure in painting.

[0029] Figure 8 It is an explanatory diagram of a preferred arrangement of the fastening portion and is a side view schematically showing the relationship with the wiring connector. DETAILED DESCRIPTION

[0030] Hereinafter, each embodiment will be described in detail with reference to the drawings. In addition, the dimensional ratios in the drawings are merely examples and are not limited thereto. In addition, for the convenience of description, the shapes and the like in the drawings may be partially exaggerated.

[0031] In the following description, the Y direction (refer to Figure 3 etc.) corresponds to the up-down direction in the use state of the vehicle drive device 100, that is, the up-down direction when the vehicle drive device 100 is arranged in its use state. Moreover, the Y1 side and the Y2 side correspond to the upper side and the lower side along the Y direction. In addition, the up-down direction does not necessarily need to be parallel to the vertical direction, as long as it mainly has a vertical direction component. In addition, the directions of the various components in the following description represent the directions in which they are assembled in the vehicle drive device 100. In addition, terms related to the size, configuration direction, configuration position, etc. of each component are concepts that include states with differences caused by errors (errors to an allowable degree in manufacturing). A direction (refer to Figure 2 etc.) corresponds to the axial direction. Figure 2 The A1 side and the A2 side along the A direction are defined in the above. Figure 3 etc.) is a direction orthogonal to both the A direction and the Y direction. Figure 3 The X1 side and the X2 side along the X direction are defined in FIG.

[0032] In this specification, "drive connection" refers to the state of connecting two rotating members in a manner that can transmit driving force (synonymous with torque), including the state of connecting the two rotating members in a manner that rotates as a whole, or the state of connecting the two rotating members in a manner that can transmit driving force via one or more transmission parts. Such transmission parts include various parts that transmit rotation at the same speed or at a variable speed (for example, shafts, gear mechanisms, belts, chains, etc.). In addition, as transmission parts, engaging devices that selectively transmit rotation and driving force (for example, friction engaging devices, meshing engaging devices, etc.) may also be included.

[0033] In addition, in this specification, "connected" refers to a state in which two space components are fluidically connected to each other. That is, it refers to a state in which a fluid can travel back and forth between the two space components. In this case, the two space components can be connected directly or indirectly (that is, via other space components).

[0034] In this specification, "rotating electric machine" is used as a concept including any one of a motor (electric motor), a generator (generator), and a motor / generator that performs the functions of both a motor and a generator as needed. In addition, in this specification, regarding the configuration of two components, "overlapping when viewed in a specific direction" means that when an imaginary straight line parallel to the line of sight is moved in directions orthogonal to the imaginary straight line, the area where the imaginary straight line intersects with both components at least partially exists. In addition, in this specification, regarding the configuration of two components, "overlapping of configuration areas in a specific direction" means that at least a part of the configuration area in a specific direction of one component is included in the configuration area in a specific direction of another component.

[0035] Figure 1 It is a schematic plan view showing a state in which the vehicle drive device 100 is mounted on the vehicle VC. Figure 2 It is a cross-sectional view of the vehicle drive device 100 . Figure 2A 1 is a schematic diagram showing a vehicle drive device 100 .

[0036] like Figure 2A As shown schematically, the vehicle drive device 100 includes a rotating electrical machine 1, and a pair of wheels W (see Figure 1 ) and a transmission mechanism 3 for transmitting driving force between the rotating electrical machine 1 and the pair of output members 6. The vehicle drive device 100 also includes a housing 2 for accommodating the rotating electrical machine 1. The housing 2 also accommodates a pair of output members 6 and the transmission mechanism 3. In addition, in a modified example, the housing 2 may accommodate only one of the pair of output members 6. In addition, as for the use of the vehicle drive device 100, it can be applied to any vehicle having a rotating electrical machine 1 such as an electric vehicle or a hybrid vehicle, and can also be applied to any vehicle with a driving mode such as front-wheel drive or rear-wheel drive. In addition, the driving source may also be only an engine (internal combustion engine).

[0037] The first output member 61 as one of the pair of output members 6 is drivingly connected to the first wheel W1 as one of the pair of wheels W, and the second output member 62 as the other of the pair of output members 6 is drivingly connected to the second wheel W2 as the other of the pair of wheels W. Figure 1As shown, the vehicle VC equipped with the vehicle drive device 100 includes a first drive shaft 63 that rotates integrally with the first wheel W1, and a second drive shaft 64 that rotates integrally with the second wheel W2. The first drive shaft 63 is connected to the first wheel W1 via a constant velocity coupling, for example, and the second drive shaft 64 is connected to the second wheel W2 via a constant velocity coupling, for example. Moreover, the first output member 61 is connected to the first drive shaft 63 in a manner that rotates integrally with the first drive shaft 63, and the second output member 62 is connected to the second drive shaft 64 in a manner that rotates integrally with the second drive shaft 64. In addition, the first output member 61 may be in the form of an intermediate shaft.

[0038] The vehicle drive device 100 transmits the output torque of the rotary electric machine 1 to a pair of wheels W via a pair of output members 6, so that the vehicle VC equipped with the vehicle drive device 100 travels. That is, the rotary electric machine 1 is a driving force source for the pair of wheels W. The pair of wheels W is a pair of left and right wheels of the vehicle VC (for example, a pair of left and right front wheels or a pair of left and right rear wheels). The rotary electric machine 1 can be, for example, an AC rotary electric machine driven by a three-phase AC.

[0039] like Figure 2 As shown, the rotating electric machine 1 and the pair of output members 6 are separately arranged on two axes parallel to each other (specifically, the first axis C1 and the second axis C2). Specifically, the rotating electric machine 1 is arranged on the first axis C1, and the pair of output members 6 are arranged on the second axis C2 different from the first axis C1. The first axis C1 and the second axis C2 are axes (imaginary axes) arranged parallel to each other. The transmission mechanism 3 has an output gear (ring gear) 30 drivingly connected to at least one of the pair of output members 6, and the output gear 30 is coaxial with the pair of output members 6 (that is, on the second axis C2).

[0040] The rotating electrical machine 1 is, for example, an inner rotor type. The rotating electrical machine 1 has a stator 11 (see Figure 2 ) is arranged radially inside the rotor 14 which can rotate around the first axis C1.

[0041] The transmission mechanism 3 has a reduction mechanism 34 in the power transmission path between the rotating motor 1 and the output gear 30. The reduction mechanism 34 is arbitrary and may include a reduction mechanism using a counter gear, a reduction mechanism using a planetary gear, etc. In the present embodiment, as an example, the reduction mechanism 34 includes a planetary gear mechanism, and the reduction mechanism 34 is coaxially arranged with the rotating motor 1. The output gear (planetary carrier) 342 of the reduction mechanism 34 is radially meshed with the output gear 30 of the differential gear mechanism 5. Such a vehicle drive device 100 can have a compact structure consisting of two shafts (a first shaft C1 and a second shaft C2). In addition, in a modified example, the vehicle drive device 100 may also have more than three shafts.

[0042] In this embodiment, the speed reduction mechanism 34 is arranged coaxially with the rotating electrical machine 1 (i.e., on the first axis C1) in a manner drivingly connected to the rotating electrical machine 1. In this embodiment, as an example, the rotor 14 of the rotating electrical machine 1 rotates integrally with the input member 16 together with the sun gear 341 of the speed reduction mechanism 34.

[0043] The transmission mechanism 3 also includes a differential gear mechanism 5. The differential gear mechanism 5 distributes the driving force transmitted from the rotating electrical machine 1 to a pair of output members 6. Figure 2 In the example shown, the differential gear mechanism 5 distributes the rotation of the output gear 30 to the first side gear 51 and the second side gear 52. The differential gear mechanism 5 can be arranged coaxially (i.e., on the second axis C2) with the pair of output members 6. In addition, the differential gear mechanism 5 can be a bevel gear type differential gear mechanism, and the output gear 30 is connected to the differential case portion 50 provided in the differential gear mechanism 5 in a manner that the output gear 30 rotates integrally with the differential case portion 50.

[0044] Next, refer to Figure 3 The following drawings illustrate the water cooling structure of the rotary electric machine 1 of the present embodiment and its related structural components (such as the flow path forming member 90 ).

[0045] Figure 3 FIG. 1 is a side view schematically showing the vehicle drive device 100 of this embodiment. Figure 3 In order to make the state in the motor housing chamber S1 clear, the motor cover member 201 is omitted from the illustration. Figure 3 In FIG. 2 , the inverter device 70 inside the inverter case portion 24 is schematically shown by a dotted line. Figure 4 is a perspective view of the flow path forming member 90. Figure 4 ( Figure 5 Similarly, the positions of the inlet 95 and the outlet 96 relative to the refrigerant flow path 300 are schematically shown in a projection diagram (circle with a single-dot chain line). Figure 4A yes Figure 4 An enlarged view of the Q4 section. Figure 5 1 is a schematic diagram of the refrigerant flow path 300 formed by the flow path forming member 90 , and is an explanatory diagram in which the outer peripheral surface of the flow path forming member 90 is developed on a plane. Fig. 6A It is a part of the refrigerant flow path 300 ( Figure 5 A cross-sectional view of the portion along line AA). Figure 6B It is a side view schematically showing the positional relationship among the first output member 61 , the refrigerant supply portion 40 , and the refrigerant discharge portion 42 . Figure 6C yes Figure 2 An enlarged view of the Q6 section.

[0046] The water cooling structure of the rotating electric machine 1 of the present embodiment is a structure for cooling the rotating electric machine 1 by cooling water. In addition, the cooling water may be water containing LLC (Long Life Coolant), for example, and may be circulated by a water pump (not shown). In addition, a heat dissipation unit such as a radiator (not shown) may be provided in the circulation path of the cooling water. In addition, the cooling water may be used not only for cooling the rotating electric machine 1, but also for cooling other structural members, such as the inverter device 70 electrically connected to the rotating electric machine 1.

[0047] like Figure 4 As shown, the water cooling structure of the rotary electric machine 1 of the present embodiment may include a refrigerant supply portion 40 , a refrigerant discharge portion 42 , and a flow path forming member 90 .

[0048] The refrigerant supply unit 40 communicates with, for example, a discharge side of a water pump (not shown), and supplies cooling water to a refrigerant flow path 300 (described later) formed by the flow path forming member 90 .

[0049] The refrigerant discharge portion 42 communicates with, for example, a suction side of a water pump (not shown), and supplies (discharges) cooling water from a refrigerant flow path 300 (described later) formed by the flow path forming member 90 to the water pump (not shown).

[0050] like Figure 6B As shown, the refrigerant supply unit 40 and the refrigerant discharge unit 42 may be provided on the upper and lower sides respectively with the first output member 61 interposed therebetween. In this case, the refrigerant supply unit 40 and the refrigerant discharge unit 42 can be established by effectively utilizing the space around the first output member 61.

[0051] like Figure 4 As shown, the flow path forming member 90 is in a cylindrical shape having an inner peripheral surface radially opposed to the outer peripheral surface of the rotating electrical machine 1. The flow path forming member 90 forms a refrigerant flow path 300 around the rotating electrical machine 1.

[0052] The flow path forming member 90 can be formed of a material with good thermal conductivity such as aluminum. In the present embodiment, as an example, the flow path forming member 90 is embedded with the stator core 12 of the stator 11 by, for example, burn-in. As a result, the close contact (interference) between the flow path forming member 90 and the stator core 12 can be improved, and the thermal resistance between the flow path forming member 90 and the stator core 12 can be reduced. In addition, in other embodiments, the flow path forming member 90 can also be formed integrally with the stator core 12 by casting or the like. In addition, the flow path forming member 90 can also be formed as a part of the housing 2.

[0053] In this embodiment, the flow path forming member 90 is taken as an example. Figure 3 As shown, it is a form of an inner shell fastened to the shell 2. In this case, as Figure 3 As shown, the flow channel forming member 90 has a plurality of fastening portions 500 on one axial end side. A preferred example of the arrangement of the plurality of fastening portions 500 will be described later.

[0054] The flow path forming member 90 is inserted into the cylindrical space portion (motor housing chamber S1) of the housing 2. At this time, the outer peripheral surface of the flow path forming member 90 is aligned with the motor housing portion 21 of the housing 2 (see Figure 2 ) are radially opposed to each other. In addition, the inner peripheral surface of the housing 2 surrounding the flow path forming member 90 is also referred to as "the flow path forming surface 209 of the housing 2" below. In addition, the inner diameter of the flow path forming surface of the housing 2 may be larger than the basic outer diameter of the stator core 12 by the basic wall thickness t0 of the flow path forming member 90 (see Fig. 6A ) constant value.

[0055] The flow path forming member 90 cooperates with the flow path forming surface 209 of the housing 2 to form the refrigerant flow path 300. Specifically, the refrigerant flow path 300 is formed between the outer peripheral surface of the flow path forming member 90 and the flow path forming surface 209 of the housing 2 in the radial direction.

[0056] The refrigerant flow path 300 may extend in the circumferential direction in such a manner that cooling water flows in the circumferential direction throughout the entire circumference. In addition, the refrigerant flow path 300 may also be formed to extend throughout the entire axial direction of the stator core 12 of the rotating electrical machine 1 and to be radially opposed to the outer peripheral surface of the stator core 12. In addition, the refrigerant flow path 300 is closed at both axial ends. For example, a sealing member 97 may be provided between the flow path forming member 90 and the flow path forming surface 209 of the housing 2, at both axial ends of the flow path forming member 90 throughout the entire circumference (see Figure 6C ).

[0057] In this embodiment, if Figure 3 as well as Figure 4 As shown, the refrigerant flow path 300 is roughly divided into a first circumferential section SC1, a second circumferential section SC2, a third circumferential section SC3, and a fourth circumferential section SC4.

[0058] The first circumferential section SC1 is a section including the inlet portion 95. The refrigerant supply portion 40 is connected to the inlet portion 95. Therefore, cooling water is introduced from the inlet portion 95 to the refrigerant flow path 300. The inlet portion 95 may be an open end portion of the refrigerant supply portion 40.

[0059] The second circumferential section SC2 is a section including the outlet portion 96. The refrigerant discharge portion 42 is connected to the outlet portion 96. Therefore, the cooling water introduced into the refrigerant flow path 300 is discharged to the outside of the refrigerant flow path 300 through the outlet portion 96. In addition, the outlet portion 96 may be in a form in which the end of the refrigerant discharge portion 42 is open.

[0060] The third circumferential interval SC3 may be an interval extending between the first circumferential interval SC1 and the second circumferential interval SC2 in the circumferential direction and having the longest circumference. The flow path forming component 90 has a convex portion 91 protruding radially in the third circumferential interval SC3 in a manner that reduces the cross-sectional area of ​​the refrigerant flow path. In the present embodiment, the convex portion 91 is in the form of a convex strip or rib extending continuously in the circumferential direction, and is formed in a manner that a plurality of convex portions are arranged in the axial direction. However, in other embodiments, the convex portion 91 may also be implemented in other forms and other configurations. For example, the convex portion in a cylindrical form may also be configured in a serrated shape. The upper surface (radially outer surface) of the convex portion 91 may be in radial contact with the flow path forming surface 209 of the shell 2, or may be slightly separated from the flow path forming surface 209 of the shell 2. In any case, the portion of the third circumferential interval SC3 in the refrigerant flow path 300 is mainly formed by a portion where the convex portion 91 is not formed.

[0061] The fourth circumferential section SC4 may be a section extending between the first circumferential section SC1 and the second circumferential section SC2 in the circumferential direction and having a circumference significantly shorter than that of the third circumferential section SC3. The flow path forming member 90 may not have a convex portion such as the convex portion 91 in the fourth circumferential section SC4. In the present embodiment, the flow path forming member 90 has a substantially flat surface (peripheral surface) in the fourth circumferential section SC4.

[0062] In this embodiment, when cooling water is introduced into the inlet portion 95 of the refrigerant flow path 300, the cooling water flows in the axial direction in the first circumferential section SC1 (see Figure 5 and is distributed to the third circumferential section SC3 and the fourth circumferential section SC4 (see arrow R52). Figure 5 In addition, the cooling water flowing in the circumferential direction in the third circumferential section SC3 (see arrows R51, R53) Figure 5 If the arrows R51 and R55) reach the second circumferential section SC2, the Figure 5 The cooling water (see arrow R54) flowing in the circumferential direction (which may also have an axial component) in the fourth axial section SC4 is discharged from the outlet portion 96. Figure 5 If the arrow R53 reaches the second circumferential section SC2, it flows in the axial direction (refer to Figure 5 , as indicated by arrow R54), and is discharged from outlet portion 96.

[0063] However, it is usually desirable to allow the fluid to flow in a flow path with low resistance. In this regard, there is a resistance component such as the convex portion 91 in the third circumferential section SC3. Therefore, if there is a flow path portion between the inlet 95 and the outlet 96 having a resistance significantly smaller than that of the third circumferential section SC3, there is a possibility that the cooling water will not fully flow to the third circumferential section SC3. In this case, there is a concern that the cooling of the portion of the stator core 12 that is radially opposite to the third circumferential section SC3 (cooling of the cooling water) will become insufficient. In particular, in the case where the resistance of the flow path portion from the inlet 95 to the outlet 96 via the fourth circumferential section SC4 is different from the relationship of this embodiment as described later and is significantly smaller, there is a concern that the cooling of the portion that is radially opposite to the third circumferential section SC3 (cooling of the cooling water) will become insufficient.

[0064] Therefore, in this embodiment, the flow path structure of the fourth circumferential section SC4 can be adjusted in such a way that the pipe loss coefficient of the fourth circumferential section SC4 is the same as the pipe loss coefficient of the third circumferential section SC3. In addition, the pipe loss coefficient can be evaluated as pipe loss coefficient = (pressure loss) / (flow rate) α . Wherein, α>1. Alternatively, from the same point of view, the flow path structure of the fourth circumferential section SC4 can be adjusted in such a way that the flow rate of the fourth circumferential section SC4 is the same as the flow rate of the third circumferential section SC3. Thus, the flow rate of the cooling water flowing in the refrigerant flow path 300 (and the cooling capacity associated therewith) can be uniformed throughout the circumference.

[0065] However, the flow rate of the fourth circumferential section SC4 and the flow rate of the third circumferential section SC3 may correspond to the ratio of the circumference of the fourth circumferential section SC4 to the circumference of the third circumferential section SC3, because the longer the circumference, the more useful the high cooling capacity is.

[0066] In the present embodiment, the maximum value of the radial width of the cross section of the refrigerant flow path 300 is the smallest in the fourth circumferential section SC4 and the largest in the third circumferential section SC3 from the first circumferential section SC1 to the fourth circumferential section SC4. Thus, the resistance in the fourth circumferential section SC4 can be made relatively large, so the flow rate of the cooling water flowing in the third circumferential section SC3 can be properly ensured. In addition, in the present embodiment, the convex portion 91 is provided in the third circumferential section SC3, so the maximum value of the radial width of the cross section of the refrigerant flow path 300 in the third circumferential section SC3 is generated in the portion without the convex portion 91.

[0067] In the present embodiment, in each of the first circumferential section SC1 to the fourth circumferential section SC4, the maximum value of the radial width of the cross section of the refrigerant flow path 300 is set to h1 to h4 (see Fig. 6A, but h2 is not shown), there is a relationship of h4

[0068] In the present embodiment, as described above, the flow path forming member 90 is disposed between the stator core 12 and the flow path forming surface 209 of the housing 2, and the radial distance between the stator core 12 and the flow path forming surface 209 of the housing 2 is substantially constant throughout the entire circumference (i.e., a constant value corresponding to the basic wall thickness t0). Therefore, in the present embodiment, the above-mentioned relationship of h4t1>t3 and t4>t2>t3 is achieved. In other words, when the wall thickness of the portion excluding the protrusion 91 is set to t4, the fourth circumferential section SC4 has the relationship of t4>t1>t3 and t4>t2>t3. In this case, t1=t2 or t1≈t2 may be satisfied. For example, t1=(t4+t3) / 2 may be satisfied.<h1>

[0069] The portion of the flow path forming member 90 that forms the refrigerant flow path 300 is the portion through which the refrigerant actually passes, and may be, for example, a portion radially opposite to the stator core 12 or a portion in the axial direction between the inlet 95 and the outlet 96 .

[0070] Here, if there is a relatively large difference in wall thickness in the flow path forming member 90 as in this embodiment, stress concentration is likely to occur due to the difference. In particular, in this embodiment, the flow path forming member 90 is burn-in, so stress concentration during burn-in is likely to become a problem. In addition, the flow path forming member 90 may shrink due to heat from the stator core 12 and the influence of cooling water, so thermal stress is likely to occur.

[0071] ​In contrast, in the present embodiment, although there is a relatively large difference in wall thickness (= t4 - t3) between the fourth circumferential section SC4 and the third circumferential section SC3 in the flow path forming member 90, the first circumferential section SC1 and the second circumferential section SC2 can mitigate the difference in wall thickness. Specifically, there are the first circumferential section SC1 and the second circumferential section SC2 having an intermediate wall thickness between the fourth circumferential section SC4 and the third circumferential section SC3. Thus, in the present embodiment, the flow path forming member 90 can mitigate the difference in wall thickness (= t4 - t3) between the fourth circumferential section SC4 and the third circumferential section SC3 in the first circumferential section SC1 and the second circumferential section SC2. As a result, the problem of stress that may be generated in the flow path forming member 90 due to the relatively large difference in wall thickness can be reduced or eliminated.

[0072] Here, as in the present embodiment, the convex portion 91 in the flow path forming member 90 also has a difference in wall thickness, so stress concentration is likely to occur at the edge of the convex portion 91. In this regard, if the circumferential end position of the convex portion 91 is set at the boundary between the third circumferential section SC3 and the first circumferential section SC1 and the second circumferential section SC2, stress concentration is likely to occur at the boundary. That is, in this case, in the boundary, stress caused by the difference in wall thickness (= t1 or t2-t3) between the third circumferential section SC3 and the first circumferential section SC1 and the second circumferential section SC2, and stress caused by the generation of the convex portion 91 are likely to occur simultaneously.

[0073] Therefore, in this embodiment, if Figure 4 as well as Figure 5 As shown, the convex portion 91 preferably ends in the first circumferential section SC1 and the second circumferential section SC2. That is, the convex portion 91 of the third circumferential section SC3 preferably extends continuously with a part of the first circumferential section SC1 and a part of the side connected to the third circumferential section, and a part of the second circumferential section SC2 and a part of the side connected to the third circumferential section SC3. Thus, it is possible to reduce stress concentration that may occur at the boundary between the third circumferential section SC3 and the first circumferential section SC1 and the second circumferential section SC2.

[0074] Furthermore, in the present embodiment, the fourth circumferential section SC4 of the flow path forming member 90 is arranged to intersect the straight line L6 connecting the axis (second axis C2) of the first output member 61 and the axis (first axis C1) of the rotary electric machine 1 when viewed in the axial direction. Thus, as described above, the refrigerant supply portion 40 and the refrigerant discharge portion 42 can be arranged vertically across the axis (second axis C2) of the first output member 61, and the space that may become a dead zone can be efficiently utilized.

[0075] Next, refer to Figure 4 , Figure 7-8 A preferred example of the arrangement of the fastening portion 500 of the flow channel forming member 90 will be described.

[0076] Figure 7 It is a side view schematically showing the vehicle drive device of this embodiment. Figure 8 8 is an explanatory diagram of a preferred configuration of the fastening portion 500, and is a side view schematically showing the relationship with the wiring connector 802. Figure 8 In the figure, for convenience of explanation, the fastening portion 500 and the wiring connector 802 arranged at different positions in the axial direction are shown in the same side view.

[0077] Hereinafter, a preferred example of the arrangement of the fastening portion 500 will be described. It is assumed that a rectangle (in this case, a square) 600 circumscribing the outer shape of the rotating electrical machine 1 when viewed in the axial direction and having two sides parallel to the vertical direction (see Figure 7 ). In addition, the outer shape of the rotating electrical machine 1 of the rectangular shape 600 may be the outer shape of the stator core 12 .

[0078] like Figure 4 as well as Figure 7 As shown, the fastening portion 500 is provided at the end portion on the A1 side of the flow path forming member 90. The fastening portion 500 is in a form that protrudes radially outward relative to the circular outer shape of the flow path forming member 90 when viewed in the axial direction. In addition, the fastening portion 500 may be formed integrally with the flow path forming member 90 or may be separate. The fastening portion 500 is fastened to the housing 2 by bolts (not shown) (bolt holes BT4). For example, the fastening portion 500 may be fastened to the motor housing portion 21 (refer to Figure 2 ) on the axial A1 side of the housing 2. Thus, the flow path forming component 90 is firmly fixed to the housing 2 via the fastening portion 500. In addition, when the fastening portion 500 is independent of the flow path forming component 90, the fastening portion may be in a plate-like form, and the axial displacement of the flow path forming component may be limited by abutting against the axial end face of the flow path forming component in the axial direction. The above-mentioned plate-like fastening portion may be formed on the axial end face of the flow path forming component, and the circumferential displacement of the flow path forming component may be limited by fitting with the recess.

[0079] The fastening portion 500 preferably overlaps with at least one of the four corners CN1 to CN4 of the rectangle 600 when viewed in the axial direction. Figure 3In the example shown, the fastening portion 500 overlaps with the corner CN1 on the X1 side and the upper side (Y1 side) and the corner CN2 on the X1 side and the lower side (Y2 side) of the housing 2, among the four corners CN1 to CN4 of the housing 2 when viewed in the axial direction. Here, the fastening portion 500 overlapping with the corner when viewed in the axial direction means that a part or all of the fastening portion 500 overlaps with the corner when viewed in the axial direction. For example, the fastening portion 500 overlapping with the corner when viewed in the axial direction may be a bolt (not shown) (bolt hole BT4) of the fastening portion 500 overlapping with the corner when viewed in the axial direction. In addition, the corner overlapped by the fastening portion 500 when viewed in the axial direction may be an area on the outside of the rotating electrical machine 1 in the rectangle 600 when viewed in the axial direction.

[0080] However, if the fixing of the flow path forming member 90 by the fastening portion 500 (fixation to the housing 2) is insufficient, there may be a problem that cooling water leaks from the refrigerant flow path 300 formed by the flow path forming member 90 or oil intrudes into the refrigerant flow path 300. In order to prevent such a problem, from the viewpoint of improving the reliability of the fixing of the flow path forming member 90 by the fastening portion 500, it is preferred that the fastening portions 500 are provided at three or more locations and are arranged at substantially equal intervals along the circumferential direction (for example, at 120 degree intervals in the case of three locations).

[0081] For example, in Fig. 7A The fastening parts 500' are shown by imaginary dotted lines when arranged at intervals of 120 degrees. In this case, the fastening parts 500' protrude from the outer shape (outer shape viewed in the axial direction) of the housing 2, which can easily lead to an increase in the volume of the housing 2 (and the volume of the vehicle drive device 100 associated therewith). In particular, in a layout where the first output member 61 is arranged in the vicinity of the rotating electrical machine 1 as in this embodiment, it is difficult to establish fastening parts at more than three positions in a manner that the fastening parts do not interfere with the first output member 61.

[0082] In this regard, in this embodiment, as described above, two of the three fastening portions 500 overlap with the corner CN1 on the X1 side and the upper side (Y1 side) and the corner CN2 on the X1 side and the lower side (Y2 side) when viewed in the axial direction. Figure 7As shown, the fastening parts 500 at three positions can be arranged at relatively uniform intervals along the circumferential direction without causing an increase in the volume of the housing 2 (and the volume of the vehicle drive device 100 associated therewith) and without interfering with the first output component 61. In addition, the relatively uniform intervals can be, for example, angular intervals that are significantly different from 120 degrees, but by being relatively uniform intervals, the required fixing strength throughout the entire circumference can be ensured. For example, when viewed in the axial direction, the center of the flow path forming component 90 (on the first axis C1) can be arranged within the triangle of the bolts (not shown) (bolt holes BT4) connecting the fastening parts 500 at the three positions. As a result, high reliability of the fixation of the flow path forming component 90 by the fastening parts 500 can be ensured, and the volume of the housing 2 (and the volume of the vehicle drive device 100 associated therewith) can be reduced.

[0083] In this embodiment, two bolts (not shown) (bolt holes BT4) are fastened to two of the three fastening portions 500. This can further improve the reliability of fixing the flow path forming member 90 by the fastening portions 500.

[0084] However, when viewed in the axial direction, the area overlapping with the corner CN1 among the four corners CN1 to CN4 is preferably used as the wiring area for the inverter housing portion 24. This is because the above-mentioned area is the upper side for the inverter housing portion 24. In addition, in particular, when the inverter housing portion 24 extends to the X1 side of the first axis C1 when viewed in the axial direction, the wiring inside the inverter housing portion 24 becomes easy to lay.

[0085] In this regard, in the present embodiment, a wiring connector 802 for an electronic component (not shown) is provided in a region between the rotary electric machine 1 and the speed reduction mechanism 34 in the axial direction and overlapping with the corner CN1 when viewed in the axial direction. In this case, the electronic component (not shown) may be a low-voltage system electronic component arranged in the motor housing chamber S1, and may include, for example, a sensor (e.g., a resolver) for detecting the rotation angle of the rotary electric machine 1, an oil temperature sensor, and the like.

[0086] In this case, one of the three fastening parts 500 overlaps with the wiring connector 802 at the corner CN1 when viewed in the axial direction. Thus, the wiring connector 802 and the fastening part 500 can be efficiently established in a manner that reduces the volume of the housing 2 (and the volume of the vehicle drive device 100 associated therewith). In other words, when the housing 2 extends to the region overlapping with the corner CN1 when viewed in the axial direction due to the provision of the wiring connector 802, the fastening part 500 is arranged to overlap with the corner CN1 when viewed in the axial direction, thereby preventing the volume of the housing 2 from being increased due to the fastening part 500.

[0087] Although each embodiment is described in detail above, it is not limited to a specific embodiment, and various modifications and changes can be made within the scope of the technical claims. In addition, all or a plurality of the structural components of the above-mentioned embodiments can also be combined.

[0088] For example, in the above-described embodiment, when the cross-sectional areas (cross-sectional areas of the flow path) of the first circumferential section SC1 to the fourth circumferential section SC4 are set to s1 to s4, the relationship of s4>s1>s3 and the relationship of s4>s2>s3 are efficiently achieved only by the wall thickness of the flow path forming member 90. However, for example, the wall thickness of the flow path forming member 90 may be set constant, and the relationship of s4>s1>s3 and the relationship of s4>s2>s3 may be achieved. For example, the relationship of s4>s1>s3 and the relationship of s4>s2>s3 may be achieved by forming a convex portion such as the convex portion 91 in the first circumferential section SC1 to the third circumferential section SC3 and making the shapes (arrangement, size) of the convex portions of the first circumferential section SC1 to the fourth circumferential section SC4 different.

[0089] In the above embodiment, the wall thickness of the flow path forming member 90 satisfies both the relationship of t4>t1>t3 and the relationship of t4>t2>t3. However, even if either one of the relationships is satisfied, part of the effect of this embodiment can be achieved.

[0090] Description of Reference Numerals

[0091] 100…vehicle drive device, 1…rotating electric machine (drive source), 11…stator core, 90…flow path forming member, 91…convex portion, 92…groove portion, 95…inlet portion (connection portion relative to the refrigerant supply portion), 96…outlet portion (connection portion relative to the refrigerant discharge portion), 40…refrigerant supply portion, 42…refrigerant discharge portion, 300…refrigerant flow path, SC1…first circumferential section, SC2…second circumferential section, SC3…third circumferential section, SC4…fourth circumferential section, 34…speed reduction mechanism (transmission mechanism), 5…differential gear mechanism (transmission mechanism), 61…first output member (shaft member), C1…first shaft (axis center of the rotating electric machine), C2…second shaft (axis center of the shaft member), W…wheel.

Claims

1. A vehicle drive device, comprising: Rotating electrical machines; The flow path forming member is a cylindrical member having an inner peripheral surface radially opposed to the outer peripheral surface of the rotating electrical machine and forming a refrigerant flow path around the rotating electrical machine; A refrigerant supply unit connected to the refrigerant flow path; a refrigerant discharge portion connected to the refrigerant flow path; and a transmission mechanism that transmits the driving force from the rotating electric machine to the wheels via the shaft member, The refrigerant flow path includes: a first circumferential section including a connection portion relative to the refrigerant supply portion; a second circumferential section including a connection portion relative to the refrigerant discharge portion; a third circumferential section on one side of two circumferential sections between the first circumferential section and the second circumferential section in the circumferential direction; and a fourth circumferential section on the other side, The flow path forming member has a convex portion protruding in the radial direction in the third circumferential section so as to reduce the cross-sectional area of ​​the refrigerant flow path. The axis of the shaft member is parallel to the axis of the rotating electrical machine and is offset in a direction intersecting the axial direction. The fourth circumferential section intersects a straight line connecting the shaft member and the axial center of the rotating electrical machine when viewed in the axial direction.

2. The vehicle drive device according to claim 1, wherein: When the flow path cross-sectional area of ​​the refrigerant flow path is s1 to s4 in each of the first to fourth circumferential sections, at least one of the relationship of s4>s1>s3 and the relationship of s4>s2>s3 is satisfied.

3. The vehicle drive device according to claim 2, wherein: In each of the first circumferential section to the fourth circumferential section, when the minimum value of the radial wall thickness of the portion of the flow path forming component that forms the refrigerant flow path is set to t1 to t4, there is at least one of the relationships of t4>t1>t3 and t4>t2>t3.

4. The vehicle drive device according to claim 2, wherein: In each of the first to fourth circumferential sections, when the radial width of the cross section of the refrigerant flow path is set to h1 to h4, and h3 represents the radial width of the groove portion adjacent to the convex portion, there is a relationship of h4<h1<h3 and h4<h2<h3.

5. The vehicle drive device according to claim 1, wherein: The convex portion in the third circumferential section is continuous with a portion of the first circumferential section and a portion of the side connected to the third circumferential section, and a portion of the second circumferential section and a portion of the side connected to the third circumferential section.

6. The vehicle drive device according to any one of claims 1 to 5, wherein: The flow path forming member is fitted to the stator core of the rotating electrical machine by shrink-fitting.

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