Drive unit

Abstract

To provide a drive device that can suppress the increase in size. [Solution] One aspect of the drive device of the present invention includes a motor having a rotor rotatable about a central axis and a stator facing the rotor, a control unit for controlling the motor, a power transmission unit having a differential gear for transmitting power from the motor, and a housing having a first housing for housing the motor, a second housing for housing the power transmission unit, and a third housing for housing the control unit. The differential gear has a ring gear. The first housing has a cylindrical wall portion surrounding the motor from the radially outer side, and a motor cover covering an opening on one axial side of the cylindrical wall portion. The direction perpendicular to the axial direction is defined as the first direction. The second housing portion is located on the other axial side of the first housing portion. The third housing portion overlaps the motor cover in the first direction. The other axial end of the third housing portion is located on one axial side of the other axial end of the ring gear.

Description

Technical Field

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

Background Art

[0002] In recent years, drive devices including a motor and an inverter connected to the motor have been developed as drive devices for electric vehicles and the like. Such a drive device is provided with a conductive member that electrically connects the motor and the power converter (for example, Patent Document 1). In addition, a housing of such a drive device may be provided with a fluid flow path in some cases.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Depending on the arrangement of the conductive member and the flow path, the drive device may be increased in size.

[0005] In view of the above circumstances, one of the objects of the present invention is to provide a drive device that can suppress an increase in size.

Means for Solving the Problems

[0006] One aspect of the drive device of the present invention comprises a motor having a rotor rotatable about a central axis and a stator facing the rotor, a control unit for controlling the motor, a busbar unit having a busbar for electrically connecting the motor and the control unit, and a housing provided with a motor housing space for housing the motor, a control unit housing space for housing the control unit, and a busbar housing space for housing the busbar unit. The housing has a motor cover located on one axial side of the motor housing space, a partition wall portion separating the busbar housing space and the control unit housing space, and a connecting flow path portion connecting the partition wall portion and the motor cover and arranged in the busbar housing space. Two directions that are perpendicular to the axial direction and perpendicular to each other are designated as the first and second directions. The busbar housing space is a space continuous with the motor housing space and is located on one side of the motor housing space in the second direction. The busbar unit, when viewed from the axial direction, overlaps the connecting flow path portion in the first direction. [Effects of the Invention]

[0007] According to one aspect of the present invention, a drive device can be provided that can suppress an increase in size. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view of a drive device according to one embodiment. [Figure 2] Figure 2 is a front view of a drive device according to one embodiment. [Figure 3] Figure 3 is a schematic cross-sectional view of the drive mechanism along the line III-III in Figure 2. [Figure 4] Figure 4 is a schematic cross-sectional view of the drive mechanism along the line IV-IV in Figure 2. [Figure 5] Figure 5 is a perspective view of a busbar unit and pipes according to one embodiment. [Figure 6] Figure 6 is a front view showing the busbar unit and the fourth flow channel section of Modified Example 1. [Figure 7]Figure 7 is a schematic diagram showing the arrangement of the busbar and the fourth flow channel in the modified example 2. [Figure 8] Figure 8 is a schematic diagram showing the arrangement of the busbar and the fourth flow channel in Modification 3. [Modes for carrying out the invention]

[0009] The following description will explain a rotating electric machine and a drive unit according to one embodiment of the present invention, with reference to the drawings. In the following description, the vertical direction will be defined and explained based on the positional relationship when the drive unit is mounted on a vehicle located on a horizontal road surface.

[0010] The drawings show the XYZ coordinate system as a three-dimensional Cartesian coordinate system where appropriate. In the XYZ coordinate system, the direction in which the Z axis extends is the vertical direction. The vertical direction is, for example, the vertical direction. Note that in this specification, the vertical direction means the vertical direction from one viewpoint and does not necessarily mean the vertical direction. The direction in which the X axis extends is the longitudinal direction of the vehicle on which the drive unit 100 is mounted. The direction in which the Y axis extends is perpendicular to both the X and Z axes and is parallel to the first axis (center axis) J1 of the motor 2. The direction in which the Y axis extends is the lateral direction of the vehicle, that is, the vehicle width direction.

[0011] In the following explanation, unless otherwise specified, the direction parallel to the first axis J1 of motor 2 (the Y-axis direction) will simply be referred to as the "axial direction." Furthermore, the radial direction centered on the first axis J1 will simply be referred to as the "radial direction," and the circumferential direction centered on the first axis J1, that is, the direction around the axis of the first axis J1, will simply be referred to as the "circumferential direction."

[0012] In this specification, one direction perpendicular to the axial direction Y is defined as the first direction Z. The direction perpendicular to both the axial direction Y and the first direction Z is defined as the second direction X. That is, the first direction Z and the second direction X are two directions that are perpendicular to the axial direction Y and perpendicular to each other. In this specification, one side of the first direction (+Z) is the side to which the arrow indicating the Z axis in the figure points, and the other side of the first direction (-Z) is the opposite side of the side to which the arrow indicating the Z axis in the figure points. One side of the second direction (+X) is the side to which the arrow indicating the X axis in the figure points, and the other side of the second direction (-X) is the opposite side of the side to which the arrow indicating the X axis in the figure points. One side of the axial direction (+Y) is the side to which the arrow indicating the Y axis in the figure points, and the other side of the axial direction (-Y) is the opposite side of the side to which the arrow indicating the Y axis in the figure points.

[0013] (Drive system) Figure 1 is a perspective view of a drive unit 100 according to one embodiment. Figure 2 is a front view of the drive unit 100 with the motor cover 61 removed, viewed from one axial side (+Y). Figure 3 is a schematic cross-sectional view of the drive unit 100 along the line III-III in Figure 2. Figure 4 is a schematic cross-sectional view of the drive unit 100 along the line IV-IV in Figure 2.

[0014] The drive unit 100 of this embodiment is installed in a vehicle that uses a motor as a power source, such as a hybrid electric vehicle (HEV), a plug-in hybrid vehicle (PHV), or an electric vehicle (EV), and is used as its power source.

[0015] As shown in Figure 3, the drive unit 100 comprises a motor 2, a power transmission unit 3, a control unit 7, a busbar unit 70, a housing 6, a pump 9, and a cooler 8. The housing 6 houses the motor 2, the power transmission unit 3, the control unit 7, and the busbar unit 70.

[0016] (motor) The motor 2 of the present embodiment is, for example, a three-phase AC motor. The motor 2 may be a single-phase or N-phase (N is a natural number of 2 or more) AC motor, or may be a DC motor. The motor 2 may have only one of a function as an electric motor and a function as a generator, or may have both of these functions.

[0017] The motor 2 includes a rotor 20 and a stator 25. The stator 25 of the present embodiment is located on the radially outer side of the rotor 20. The motor 2 of the present embodiment is an inner rotor type motor. However, the motor 2 may be an outer rotor type motor, or may be an axial gap type motor.

[0018] The rotor 20 is rotatable around a first axis (central axis) J1. The rotor 20 includes a motor shaft 21 extending in the axial direction Y around the first axis J1, a rotor core 24 fixed to the motor shaft 21, and a rotor magnet (not shown) fixed to the rotor core 24. The motor 2 may be a motor having no rotor magnet, such as an induction motor or a reluctance motor.

[0019] The motor shaft 21 is connected to the power transmission unit 3. Thereby, when the motor 2 is driven, the torque of the rotor 20 is transmitted to the power transmission unit 3. The motor shaft 21 is a hollow shaft having a hollow portion 21h inside. The hollow portion 21h opens at both end portions of the motor shaft 21.

[0020] The stator 25 faces the rotor 20 in the radial direction. The stator 25 surrounds the rotor 20 from the radially outer side. The stator 25 is held by the housing 6. The stator 25 includes an annular stator core 27 and a coil 26 mounted on the stator core 27. The coil 26 is connected to the control unit 7 via the bus bar unit 70.

[0021] As shown in Figure 2, the stator 25 has a plurality (three in this embodiment) of terminal members 26a. The terminal members 26a extend radially outward from the coil end, which is the axial end (+Y) of the coil 26. In this embodiment, the tip of the terminal member 26a is plate-shaped with the axial direction Y being the thickness direction. The terminal members 26a are connected to the busbar unit 70.

[0022] (Power transmission section) As shown in Figure 3, the power transmission unit 3 is located on the other axial side (-Y) of the motor 2. The power transmission unit 3 transmits power from the motor 2. The power transmission unit 3 is connected to the rotor 20. A pair of output shafts 55 are also connected to the power transmission unit 3. The power transmission unit 3 reduces or increases the rotation of the rotor 20 and transmits it to the output shafts 55.

[0023] The power transmission unit 3 includes a first shaft 44, a second shaft 45, a first gear 41, a second gear 42, a third gear 43, and a differential gear 5.

[0024] The first shaft 44 extends axially Y about the first axis J1. The first shaft 44 is rotatable about the first axis J1. The first shaft 44 is connected at one axial end (+Y) to the other axial end (-Y) of the motor shaft 21 and rotates together with the rotor 20. Note that the first shaft 44 and the motor shaft 21 are a single component, or the first shaft 44 and the motor shaft 21 may be parts of that single component. The first gear 41 is provided on the outer circumferential surface of the first shaft 44. The first gear 41 rotates together with the rotor 20 about the first axis J1.

[0025] The second shaft 45 extends in the axial direction Y, centered on the second axis J2 which extends parallel to the first axis J1. The second shaft 45 is rotatable about the second axis J2. The second gear 42 and the third gear 43 are provided on the outer circumferential surface of the second shaft 45. The second gear 42 meshes with the first gear 41.

[0026] The differential gear 5 includes a ring gear 51 and a differential mechanism 5a. The differential gear 5 is rotatable about a third axis J3 that is parallel to the first axis J1 and the second axis J2. The ring gear 51 meshes with the third gear 43. A pair of output shafts 55 are connected to the differential mechanism 5a. Each of the pair of output shafts 55 is provided with a wheel (not shown). When the vehicle turns, the differential mechanism 5a absorbs the speed difference between the left and right wheels and transmits torque to the pair of output shafts 55.

[0027] (Control Unit) The control unit 7 is electrically connected to the motor 2 via a busbar unit 70. The control unit 7 controls the motor 2. The control unit 7 functions, for example, as an inverter. In this case, the control unit 7 has a power board, capacitors, switching elements, etc., and converts a DC current supplied from a battery (not shown) into an AC current.

[0028] As shown in Figure 2, the control unit 7 has a plurality (three in this embodiment) of control busbars 7a. For example, alternating currents with different phases flow through the plurality of control busbars 7a. The control busbars 7a are connected to the motor 2 via a busbar unit 70.

[0029] The control busbar 7a is plate-shaped with the axial direction Y as the thickness direction. The control busbar 7a extends along the first direction Z. Multiple control busbars 7a are arranged side by side along the second direction X. As shown in Figure 4, the control busbar 7a is supported by the control busbar holder 7b.

[0030] (Bus bar unit) Figure 5 is a perspective view of the busbar unit 70 and pipe 94A of this embodiment. As shown in Figures 1 and 5, the busbar unit 70 includes a plurality (three in this embodiment) of busbars 71, 72, and 73, a busbar holder 75 that holds the plurality of busbars 71, 72, and 73, and a plurality (three in this embodiment) of nuts 77.

[0031] In this embodiment, the busbars 71, 72, and 73 are encased in the busbar holder 75 by insert molding and are formed integrally with the busbar holder 75. In this specification, "encased" means that at least a portion of it is embedded inside.

[0032] The busbars 71, 72, and 73 are made of plate-shaped conductive members. For example, the busbars 71, 72, and 73 can be made of metallic materials with high electrical conductivity, such as copper. In this embodiment, for example, alternating currents with different phases flow through the multiple busbars 71, 72, and 73 when the drive unit 100 is operating. Each of the multiple busbars 71, 72, and 73 electrically connects the motor 2 and the control unit 7.

[0033] Each of the busbars 71, 72, and 73 has a first connecting end 71a, 72a, 73a, a second connecting end 71b, 72b, 73b, and a busbar body portion 71c, 72c, 73c.

[0034] Multiple busbar body sections 71c, 72c, and 73c connect the first connection ends 71a, 72a, and 73a and the second connection ends 71b, 72b, and 73b of each busbar 71, 72, and 73. At least a portion of each of the three busbar body sections 71c, 72c, and 73c is contained within and supported by the busbar holder 75. The three busbar body sections 71c, 72c, and 73c overlap each other in the axial direction Y.

[0035] The three first connecting ends 71a, 72a, and 73a are located at the ends of the busbars 71, 72, and 73 on the other side (-X) in the second direction, respectively. The three first connecting ends 71a, 72a, and 73a are exposed from the busbar holder 75. The thickness direction of the three first connecting ends 71a, 72a, and 73a coincides with the axial direction Y. The three first connecting ends 71a, 72a, and 73a are aligned along the circumferential direction of the first axis J1. In this embodiment, the first connecting ends 71a, 72a, and 73a consist of plate-shaped members joined to the busbar body portion 71c by joining means such as welding. However, in each of the busbars 71, 72, and 73, the first connecting ends 71a, 72a, and 73a and the busbar body portions 71c, 72c, and 73c are made of a single component, and the first connecting ends 71a, 72a, and 73a may be part of the busbar body portions 71c, 72c, and 73c.

[0036] As shown in Figures 2 and 5, the three first connecting ends 71a, 72a, and 73a are each connected to the terminal member 26a. The thickness direction of the first connecting ends 71a, 72a, and 73a coincides with the thickness direction of the terminal member 26a (i.e., the axial direction Y in this embodiment). The three first connecting ends 71a, 72a, and 73a are each arranged overlapping on one axial side (+Y) of the terminal member 26a. Through holes are provided in the three first connecting ends 71a, 72a, and 73a and the three terminal members 26a, respectively, that penetrate in the thickness direction. First connecting bolts 78 are inserted into the through holes of the overlapping first connecting ends 71a, 72a, and 73a and the terminal member 26a, respectively. Nuts (not shown) are placed on the other axial side (-Y) of the overlapping first connecting ends 71a, 72a, and 73a and the terminal member 26a, respectively. When the first connecting bolt 78 is tightened into the nut, the three first connecting ends 71a, 72a, and 73a are fastened to the terminal member 26a and electrically connected.

[0037] The second connecting ends 71b, 72b, and 73b are located at the ends of the busbars 71, 72, and 73 on one side (+X) in the second direction, respectively. The three second connecting ends 71b, 72b, and 73b are each exposed from the busbar holder 75. The thickness direction of the three second connecting ends 71b, 72b, and 73b coincides with the axial direction Y. The three second connecting ends 71b, 72b, and 73b are aligned along the second direction X. The three second connecting ends 71b, 72b, and 73b each extend along the second direction X.

[0038] As shown in Figure 2, the three second connecting ends 71b, 72b, and 73b are each connected to the control bus bar 7a. The thickness direction of the second connecting ends 71b, 72b, and 73b coincides with the thickness direction of the control bus bar 7a (i.e., the axial direction Y in this embodiment). The three second connecting ends 71b, 72b, and 73b are each arranged overlapping on the other axial side (-Y) of the control bus bar 7a. Through holes are provided in the second connecting ends 71b, 72b, and 73b and the control bus bar 7a, respectively, that penetrate in the thickness direction. As shown in Figure 4, second connecting bolts 79 are inserted into the through holes of the overlapping second connecting ends 71b, 72b, and 73b and the control bus bar 7a. Nuts 77 are placed on the other axial side (-Y) of the overlapping second connecting ends 71b, 72b, and 73b and the control bus bar 7a. When the second connecting bolt 79 is tightened onto the nut 77, the three second connecting ends 71b, 72b, and 73b are fastened to the control bus bar 7a and electrically connected.

[0039] In the following explanation, when distinguishing between the three bus bars 71, 72, and 73, they will be referred to as the first bus bar 71, the second bus bar 72, and the third bus bar 73.

[0040] As shown in Figure 5, in this embodiment, the busbar body portion 73c of the third busbar 73 is a flat plate shape perpendicular to the axial direction Y. The busbar body portion 73c of the third busbar 73 has a first portion 73z extending in a first direction Z and a second portion 73x extending in a second direction X. The end of the first portion 73z on one side (+Z) in the first direction and the end of the second portion 73x on the other side (-X) in the second direction are connected to each other. The first connecting end 73a of the third busbar 73 extends from the end of the first portion 73z on the other side (-Z) in the first direction to the other side (-Z). The second connecting end 73b of the third busbar 73 extends from the end of the second portion 73x on one side (+X) in the second direction to the other side (+X). That is, the shape of the third busbar 73 when viewed from the axial direction Y is L-shaped.

[0041] In this embodiment, the busbar body portion 72c of the second busbar 72 is bent in the axial direction Y. The busbar body portion 72c of the second busbar 72 extends in the second direction X when viewed from the axial direction Y. The busbar body portion 72c of the second busbar 72 is positioned on the other axial side (-Y) of the busbar body portion 73c of the third busbar 73. That is, the second busbar 72 overlaps with the third busbar 73 in the axial direction Y. The first connecting end 72a of the second busbar 72 extends from the end of the busbar body portion 72c on the other side (-X) in the second direction to the other side (-Z) in the first direction. The second connecting end 72b of the second busbar 72 extends from the end of the busbar body portion 72c on one side (+X) in the second direction to one side (+X) in the second direction.

[0042] In this embodiment, the busbar body portion 71c of the first busbar 71 is bent in the axial direction Y. The busbar body portion 71c of the first busbar 71 extends in the second direction X when viewed from the axial direction Y. The busbar body portion 71c of the first busbar 71 is positioned on the other axial side (-Y) of the busbar body portion 72c of the second busbar 72 and the busbar body portion 73c of the third busbar 73. That is, the first busbar 71 overlaps with the second busbar 72 and the third busbar 73 in the axial direction Y. The first connecting end 71a of the first busbar 71 extends from the end of the busbar body portion 71c on the other side (-X) in the second direction to the other side (-X). The second connecting end 71b of the first busbar 71 extends from the end of the busbar body portion 71c on one side (+X) in the second direction to the one side (+X).

[0043] The busbar holder 75 holds the busbar bodies 71c, 72c, 73c of multiple busbars 71, 72, and 73, as well as multiple nuts 77. The busbar holder 75 is made of a highly insulating resin material or the like.

[0044] The busbar holder 75 in this embodiment holds multiple busbars 71, 72, and 73. However, the busbar holder 75 does not necessarily have to hold multiple busbars 71, 72, and 73, as long as it can hold multiple busbars 71, 72, and 73.

[0045] The busbar holder 75 includes a holder body 75g, a first fixing part 75a, a second fixing part 75b, a first positioning pin 75c, and a second positioning pin 75e.

[0046] In the axial direction Y, the thickness of the holder body portion 75g of this embodiment is greater than the combined thickness of at least three busbars 71, 72, and 73 aligned in the axial direction Y. The holder body portion 75g holds multiple busbars 71, 72, and 73 and multiple nuts 77. Multiple (three in this embodiment) retaining recesses 75h are provided on the surface of the holder body portion 75g facing one side in the first direction (+Z). Retaining recesses 75h are located on the other axial side (-Y) of each second connecting end 71b, 72b, and 73b. Each retaining recess 75h accommodates a nut 77.

[0047] In this embodiment, the first fixing portion 75a and the second fixing portion 75b are plate-shaped and extend along a plane perpendicular to the axial direction Y. The first fixing portion 75a protrudes from the holder body portion 75g to one side in the second direction (+X). The second fixing portion 75b protrudes from the holder body portion 75g to the other side in the first direction (-Z). The first fixing portion 75a and the second fixing portion 75b are each provided with through holes 75d that penetrate in the axial direction Y. A cylindrical collar member 75k extending in the axial direction Y is disposed in each through hole 75d. The collar member 75k is made of, for example, a metal material. The collar member 75k is incorporated into the busbar holder 75, for example, by insert molding. As a result, the collar member 75k is supported by the first fixing portion 75a and the second fixing portion 75b, respectively. Fixing bolts 76 for fixing the busbar unit 70 to the housing 6 are inserted into the collar member 75k. The axial Y-sides of the collar member 75k contact the fixing bolts 76 and the housing 6, respectively. Since the fixing bolts 76 are fastened to the busbar holder 75 and the housing 6, stress is applied to the busbar holder 75 by the fastening of the fixing bolts 76. However, by providing the collar member 75k in the through hole 75d, the stress applied to the busbar holder 75 by the fastening of the fixing bolts 76 can be suppressed, and the busbar holder 75 can be protected from deformation and breakage. Note that if the strength of the busbar holder 75 is sufficiently ensured against the fastening force of the fixing bolts 76, the collar member 75k may be omitted.

[0048] The first positioning pin 75c and the second positioning pin 75e are aligned along the second direction X. The first positioning pin 75c and the second positioning pin 75e are each cylindrical in shape. The first positioning pin 75c protrudes from the first fixing portion 75a in the other axial direction (-Y). The second positioning pin 75e protrudes from the holder body portion 75g in the other axial direction (-Y). The first positioning pin 75c and the second positioning pin 75e are inserted into positioning holes (not shown) provided on the surface of the partition wall portion 66d (which will be described later) facing one axial direction (+Y). This allows the busbar unit 70 to be positioned relative to the housing 6.

[0049] The positioning structure of the busbar unit 70 relative to the housing 6 is not limited to this embodiment. For example, the first positioning pin 75c and the second positioning pin 75e may have shapes other than cylinders, as long as they are protrusions that can be inserted into positioning recesses (e.g., positioning holes) on the housing 6 side. Furthermore, the busbar unit 70 may be positioned relative to other parts of the housing 6. For example, the positioning pins of the busbar unit 70 may protrude in one axial direction (+Y) and be inserted into positioning holes provided in the motor cover 61, which will be described later.

[0050] (housing) As shown in Figure 3, the housing 6 is provided with a motor housing space A3 in which the motor 2 is housed, a control unit housing space A1 in which the control unit 7 and cooler 8 are housed, a gear housing space A2 in which the power transmission unit 3 is housed, and a busbar housing space A4 in which the busbar unit 70 is housed.

[0051] As shown in Figure 1, the housing 6 comprises a housing body 60, a motor cover 61, a gear cover 62, and a control unit cover 63. In this embodiment, the housing body 60, motor cover 61, gear cover 62, and control unit cover 63 are separate components. The motor cover 61 is located on one axial side (+Y) of the housing body 60. The gear cover 62 is located on the other axial side (-Y) of the housing body 60. The control unit cover 63 is located on one side (+Z) of the housing body 60 in the first direction.

[0052] The housing body 60 includes a cylindrical wall portion 60a, an extended wall portion 66, a control unit case 64, a gear case 65, and a bracket 69. In this embodiment, the housing body 60 is a single component in which the cylindrical wall portion 60a, the extended wall portion 66, the control unit case 64, the gear case 65, and the bracket 69 are integrated. However, the cylindrical wall portion 60a, the extended wall portion 66, the control unit case 64, the gear case 65, and the bracket 69 may each be separate components.

[0053] As shown in Figures 1 and 3, the cylindrical wall portion 60a is substantially cylindrical, extending in the axial direction Y with respect to the first axis J1. The cylindrical wall portion 60a surrounds the motor 2 from the radial outside. The other axial end (-Y) of the cylindrical wall portion 60a is connected to the first side wall portion 65a, which will be described later. The opening on one axial side (+Y) of the cylindrical wall portion 60a is covered by the motor cover 61. The motor 2 is housed in the space enclosed by the cylindrical wall portion 60a, the first side wall portion 65a, and the motor cover 61. In other words, the motor housing space A3 is the internal space enclosed by the cylindrical wall portion 60a, the first side wall portion 65a, and the motor cover 61. The motor cover 61 is located on one axial side (+Y) of the motor housing space A3.

[0054] The expanded wall portion 66 connects to one axial end (+Y side) of the cylindrical wall portion 60a. The expanded wall portion 66 opens to one axial side (+Y). The opening of the expanded wall portion 66 connects to the opening on one axial side (+Y) of the cylindrical wall portion 60a. The opening of the expanded wall portion 66, together with the opening of the cylindrical wall portion 60a, is covered by the motor cover 61. The space enclosed by the expanded wall portion 66 and the motor cover 61 connects to the space enclosed by the cylindrical wall portion 60a and the motor cover 61. In other words, the expanded wall portion 66 expands the internal space of the cylindrical wall portion 60a radially outward.

[0055] As shown in Figures 2 and 3, the busbar unit 70 is housed in the space enclosed by the extension wall 66 and the motor cover 61. That is, the busbar housing space A4 is an internal space enclosed by the extension wall 66 and the motor cover 61. The busbar housing space A4 is a space continuous with the motor housing space A3. That is, there is no wall between the busbar housing space A4 and the motor housing space A3. Also, the busbar housing space A4 is located on one side (+X) of the motor housing space in the second direction. That is, the busbar housing space A4 extends from the motor housing space A3 on one side (+X) in the second direction. On the other hand, as shown in Figure 4, a part of the extension wall 66 (the partition wall 66d and upper wall 66a described later) is provided as a wall between the busbar housing space A4 and the control unit housing space A1. At least a part of the busbar housing space A4 is located on one side (+Y) in the axial direction of the control unit housing space A1. Furthermore, at least a portion of the busbar housing space A4 is located on the other side (-Z) of the control unit housing space A1 in the first direction.

[0056] As shown in Figure 2, the extended wall portion 66 has an upper wall portion 66a, a lower wall portion 66b, a side wall portion 66c, and a partition wall portion 66d. That is, the housing 6 has a partition wall portion 66d.

[0057] The upper wall portion 66a and the lower wall portion 66b extend along a plane perpendicular to the first direction Z. The upper wall portion 66a and the lower wall portion 66b face each other in the first direction Z. The upper wall portion 66a is located on one side (+Z) of the busbar housing space A4 in the first direction. The lower wall portion 66b is located on the other side (-Z) of the busbar housing space A4 in the first direction.

[0058] As shown in Figure 4, the upper wall portion 66a is located on the other side (-Z) of the control unit housing space A1 in the first direction. Therefore, the upper wall portion 66a divides the busbar housing space A4 and the control unit housing space A1 in the first direction Z.

[0059] A through-hole 66h is provided in the upper wall portion 66a. The through-hole 66h penetrates the upper wall portion 66a in the first direction Z. As a result, the through-hole 66h connects the busbar housing space A4 and the control unit housing space A1. Multiple control unit busbars 7a pass through the through-hole 66h. The through-hole 66h is also closed by a control unit busbar holder 7b that supports the control unit busbars 7a.

[0060] As shown in Figure 2, the side wall portion 66c extends along a plane perpendicular to the second direction X. The side wall portion 66c is located on one side (+X) of the busbar housing space A4. The side wall portion 66c connects to the ends of the upper wall portion 66a and the lower wall portion 66b on one side (+X) of the second direction. The side wall portion 66c is located on one side (+X) of the motor housing space A3, with the busbar housing space A4 in between.

[0061] The partition wall portion 66d extends along a plane perpendicular to the axial direction Y. The partition wall portion 66d connects to the other axial side (-Y) end of the upper wall portion 66a, the lower wall portion 66b, and the side wall portion 66c. Multiple (two in this embodiment) screw holes (not shown) are provided on the surface of the partition wall portion 66d facing one axial side (+Y). Fixing bolts 76 inserted into the first fixing portion 75a and the second fixing portion 75b of the busbar holder 75 are tightened into the two screw holes. In this way, the busbar unit 70 is fixed to the partition wall portion 66d.

[0062] As shown in Figure 3, the partition wall 66d is located on the other axial side (-Y) of the busbar housing space A4. The partition wall 66d is also located on one axial side (+Y) of the control unit housing space A1. The partition wall 66d separates the busbar housing space A4 and the control unit housing space A1 in the axial direction Y.

[0063] As shown in Figure 1, the bracket 69 is provided on the outer surface of the housing 6. The bracket 69 is plate-shaped and extends along a plane perpendicular to the axial direction Y. The bracket 69 extends from the outer surface of the cylindrical wall portion 60a. The bracket 69 is provided with a retaining hole 69h. The retaining hole 69h penetrates the bracket 69 in the axial direction Y. In this embodiment, the retaining hole 69h is circular with the third axis J3 as viewed from the axial direction Y. The bearing 69a and the output shaft 55 are inserted into the retaining hole 69h. The bracket 69 rotatably supports the output shaft 55 via the bearing 69a.

[0064] The motor cover 61 is fixed to the housing body 60 from one axial side (+Y). As shown in Figure 3, the motor cover 61 is located on one axial side (+Y) of the motor 2 and the busbar unit 70. A bearing B8 is attached to the motor cover 61. The motor cover 61 rotatably supports one axial end (+Y) of the motor shaft 21 via the bearing B8.

[0065] The gear case 65 has a first side wall portion 65a and a first circumferential wall portion 65b. The first side wall portion 65a extends along a plane perpendicular to the axial direction Y. The first side wall portion 65a is located on one axial side (+Y) of the gear housing space A2. Bearings B1, B2, and B3 are mounted on the first side wall portion 65a. The first side wall portion 65a rotatably supports the first shaft 44, the motor shaft 21, and the second shaft 45, respectively, via the bearings B1, B2, and B3. Also, as shown in Figure 1, a bearing B4 is arranged on the first side wall portion 65a. The first side wall portion 65a rotatably supports the differential gear 5 via the bearing B4. The first circumferential wall portion 65b extends from the outer edge of the first side wall portion 65a to the other axial side (-Y). The first peripheral wall portion 65b is located radially outward of the gear housing space A2 and surrounds the power transmission portion 3 from the radially outward direction.

[0066] As shown in Figure 3, at least a portion of the first side wall 65a is located between the motor housing space A3 and the gear housing space A2 in the axial direction Y, and separates the motor housing space A3 and the gear housing space A2. The first side wall 65a is provided with a through hole 65h that penetrates the first side wall 65a in the axial direction Y. Inside the through hole 65h, a connecting portion is arranged to connect the motor shaft 21 and the first shaft 44.

[0067] The gear cover 62 is fixed to the first circumferential wall portion 65b. The gear cover 62 covers the opening of the gear case 65 from the other axial side (-Y) of the gear case 65. The gear cover 62 has a second side wall portion 62a and a second circumferential wall portion 62b. The second side wall portion 62a extends along a plane perpendicular to the axial direction Y. The second side wall portion 62a is located on the other axial side (-Y) of the gear housing space A2. Bearings B5, B6, and B7 are arranged on the second side wall portion 62a. The second side wall portion 62a rotatably supports the first shaft 44, the second shaft 45, and the differential gear 5, respectively, via the bearings B5, B6, and B7. The second circumferential wall portion 62b extends from the outer edge of the second side wall portion 62a to one axial side (+Y). The second circumferential wall portion 62b is located radially outward of the gear housing space A2 and surrounds the power transmission section 3 from the radially outward direction. The first circumferential wall portion 65b and the second circumferential wall portion 62b are connected to each other in the axial direction Y.

[0068] As shown in Figure 1, the control unit case 64 is located on one side (+Z) in the first direction of the cylindrical wall portion 60a. In this embodiment, the control unit case 64 is provided on the outer circumferential surface of the cylindrical wall portion 60a. The control unit case 64 is box-shaped and opens on one side (+Z) in the first direction. The opening of the control unit case 64 is covered by the control unit cover 63. The control unit cover 63 is located on one side (+Z) in the first direction of the control unit housing space A1.

[0069] As shown in Figure 3, the housing 6 has a first housing section 6A, a second housing section 6B, and a third housing section 6C. The first housing section 6A has a control unit housing space A1 inside. The second housing section 6B has a gear housing space A2 inside. The third housing section 6C has a motor housing space A3 and a busbar housing space A4 inside. The first housing section 6A, the second housing section 6B, and the third housing section 6C are composed of the housing body 60, the motor cover 61, the gear cover 62, and the control unit cover 63, respectively. The first housing section 6A is composed of the control unit case 64 and the control unit cover 63 of the housing body 60. The second housing section 6B is composed of the gear case 65 and the gear cover 62 of the housing body 60. The third housing section 6C is composed of the cylindrical wall section 60a, the expanded wall section 66, and the first side wall section 65a of the housing body 60, and the motor cover 61. Note that the combination of components constituting the first housing section 6A, the second housing section 6B, and the third housing section 6C in this embodiment is merely an example, and other combinations may be used.

[0070] A flow path 90 is provided in the housing 6. In this embodiment, the flow path 90 is a path through which the fluid O circulates within the drive unit 100. The flow path 90 has a first flow path section 91, a second flow path section 92, a third flow path section 93, a fourth flow path section (connecting flow path section) 94, and a fifth flow path section 95. In this embodiment, the first flow path section 91, the second flow path section 92, the third flow path section 93, and the fifth flow path section 95 are holes provided in the wall of the housing 6. On the other hand, the fourth flow path section 94 is a flow path that passes inside the pipe 94A. That is, the pipe 94A is provided in the path of the flow path 90. In addition, the pump 9 and the cooler 8 are provided in the path of the flow path 90.

[0071] The pump 9 is fixed, for example, to the outer surface of the second housing section 6B (first peripheral wall section 65b). The pump 9 sucks the fluid O that accumulates at the bottom of the gear housing space A2 and supplies it to the first flow path section 91.

[0072] The first flow channel section 91 connects the pump 9 and the cooler 8. In this embodiment, the cooler 8 is housed in the control unit housing space A1. The cooler 8 cools the fluid O supplied from the first flow channel section 91.

[0073] The second flow channel section 92 connects to the outlet of the cooler 8. The second flow channel section 92 extends axially in one direction (+Y) from the outlet of the cooler 8 and connects to a branch section 92a provided in the partition wall section 66d.

[0074] The branching section 92a is connected to the second flow channel 92, the third flow channel 93, and the fourth flow channel 94. The fluid O flowing through the second flow channel 92 branches off at the branching section 92a into the third flow channel 93 and the fourth flow channel 94.

[0075] As shown in Figure 4, the branch section 92a is a recess provided on the surface of the partition wall 66d facing one axial side (+Y) and opening to the same axial side (+Y). In this embodiment, the opening of the branch section 92a is circular when viewed from the axial direction Y. The diameter of the opening of the branch section 92a is larger than the diameters of the second flow path section 92, the third flow path section 93, and the fourth flow path section 94. The opening of the branch section 92a is covered by the pipe 94A. Note that the shape of the opening of the branch section 92a is not limited to a circle.

[0076] As shown in Figure 3, the third flow channel 93 connects the branch section 92a and the motor housing space A3. The downstream end of the third flow channel 93 opens into the motor housing space A3 on the other axial side (-Y) of the motor 2. Liquid O is discharged from the third flow channel 93 toward the motor 2.

[0077] As shown in Figure 4, the fourth channel section 94 passes through the inside of pipe 94A. Pipe 94A is housed in the busbar housing space A4. Therefore, the fourth channel section 94 is located in the busbar housing space A4. The fourth channel section 94 is located on the other side (-Z) of the first direction of the busbar unit 70.

[0078] The pipe 94A is a cylindrical body extending in the axial direction Y. The pipe 94A has a first end 94a on the other axial side (-Y) and a second end 94b on one axial side (+Y). In this embodiment, the outer diameter of the pipe 94A is expanded at the first end 94a. The first end 94a is inserted into the opening of the branch section 92a provided in the partition wall 66d. The second end 94b is inserted into a recess 95a provided in the motor cover 61. The recess 95a is provided on the surface of the motor cover 61 facing the other axial side (-Y) and opens to the other axial side (-Y). The pipe 94A connects the branch section 92a and the recess 95a. That is, the fourth flow path section 94 connects the partition wall 66d and the motor cover 61.

[0079] Although not shown in Figure 4, an O-ring is placed on the outer circumferential surface of the first end portion 94a. This prevents the fluid O in the branch portion 92a from leaking into the busbar housing space A4. Similarly, an O-ring is placed on the outer circumferential surface of the second end portion 94b. This prevents the fluid O in the recess 95a from leaking into the busbar housing space A4. Note that a sealing material other than an O-ring may be used as long as it prevents the fluid O from leaking out.

[0080] As shown in Figure 3, the fifth flow channel 95 is located inside the motor cover 61. The upstream end of the fifth flow channel 95 connects to the downstream end of the fourth flow channel 94. The fifth flow channel 95 branches into multiple flow channels; that is, the fifth flow channel 95 has multiple downstream ends. Some of the downstream ends of the fifth flow channel 95 open into the motor housing space A3 on one axial side (+Y) of the motor 2. Liquid O is discharged from the fifth flow channel 95 toward the motor 2. The other downstream end of the fifth flow channel 95 opens toward the hollow section 21h of the motor shaft 21. The fluid O supplied to the hollow section 21h is guided, for example, to the rotor core 24 to cool the rotor core 24.

[0081] In the third flow channel section 93 and the fifth flow channel section 95, the fluid O discharged into the motor housing space A3 accumulates at the bottom of the motor housing space A3 and returns to the gear housing space A2 through the through-hole (not shown) of the first side wall section 65a.

[0082] As shown in Figure 2, in the drive unit 100 of this embodiment, the busbar housing space A4 in which the busbar unit 70 is housed is a space continuous with the motor housing space A3 in which the motor 2 is housed. Furthermore, the busbar housing space A4 in this embodiment is located on one side (+X) of the motor housing space A3 in the second direction. That is, the busbar housing space A4 is a space that extends from the motor housing space A3 on one side (+X) in the second direction. According to this embodiment, the housing 6 can be made smaller in the first direction Z and the axial direction Y compared to the case in which the busbar housing space A4 is extended in the first direction Z or the axial direction Y.

[0083] Furthermore, the busbar housing space A4 of this embodiment is provided with a busbar unit 70 and a fourth flow path 94 connecting the partition wall 66d and the motor cover 61. According to this embodiment, by arranging a part of the flow path 90 provided in the housing 6 in the busbar housing space A4, the overall length of the flow path 90 can be shortened compared to the case where a flow path is provided that bypasses the busbar housing space A4. As a result, the pressure loss of the flow path 90 can be reduced.

[0084] In addition, in the busbar housing space A4 of this embodiment, the busbar unit 70 overlaps with the fourth flow channel 94 in the first direction Z when viewed from the axial direction Y. According to this embodiment, the busbar housing space A4 can be made smaller in the second direction X compared to the case where the busbar unit 70 and the fourth flow channel 94 are arranged side by side in the second direction X. As a result, the housing 6 can be made smaller in the second direction X.

[0085] Furthermore, in this embodiment, the busbar unit 70 and the fourth flow path section 94 overlap with the first direction Z, even when viewed from the second direction X (see Figure 4). Therefore, according to this embodiment, the dimensions of the busbar housing space A4 can be reduced not only in the second direction X but also in the axial direction Y.

[0086] As shown in Figure 2, in the drive unit 100 of this embodiment, a portion of the busbar unit 70 overlaps with the fourth flow path 94 in the first direction Z when viewed from the axial direction Y. Another portion of the busbar unit 70 overlaps with the fourth flow path 94 in the second direction X when viewed from the axial direction Y. According to this embodiment, the busbar unit 70 and the fourth flow path 94 can be positioned closer to the first direction Z and the second direction X when viewed from the axial direction Y. This makes it possible to reduce the size of the busbar housing space A4 in the first direction Z and the second direction X.

[0087] Furthermore, in this embodiment, the busbar unit 70 and the fourth flow path section 94 have portions that overlap with the first direction Z and the second direction X, even when viewed from the second direction. Therefore, according to this embodiment, the dimensions of the busbar housing space A4 can be reduced not only in the first direction Z and the second direction X, but also in the axial direction Y.

[0088] In this embodiment, as shown in Figure 5, the second connecting end 73b of the third busbar 73 overlaps with the fourth flow channel 94 in the first direction Z, and the first portion 73z of the third busbar 73 overlaps with the fourth flow channel 94 in the second direction X. That is, a part of one busbar 73 overlaps with the fourth flow channel 94 in the first direction Z, and another part of the same busbar 73 overlaps with the fourth flow channel 94 in the second direction X. Therefore, one busbar (the third busbar 73) can be brought closer to the fourth flow channel 94 in the first direction Z and the second direction X. If multiple busbars are brought closer to the fourth flow channel 94 in order to reduce the size of the busbar housing space A4, in some cases the busbars may get too close to each other, making it difficult to ensure insulation between the busbars. In this embodiment, by arranging the third busbar 73 and the fourth flow channel 94 close together, the degree of freedom in arranging the other busbars is increased. Therefore, the first busbar 71 and the second busbar 72 can be positioned at a distance from the third busbar 73. Consequently, even if the first busbar 71 and the second busbar 72 are positioned with sufficient insulation distance from the third busbar 73, the busbar housing space A4 can be made smaller.

[0089] In this embodiment, not only the third busbar 73 but also the second busbar 72 have a portion that overlaps with the fourth flow path 94 in the first direction Z, and another portion that overlaps in the second direction X. Therefore, not only the third busbar 73 but also the second busbar 72 can be brought closer to the fourth flow path 94 in both the first direction Z and the second direction X. In this embodiment, the first busbar 71 has a portion that overlaps with the fourth flow path 94 in the first direction Z, but does not have a portion that overlaps in the second direction X.

[0090] In this embodiment, when the busbar unit 70 includes a plurality of busbars 71, 72, and 73, it is preferable that at least a portion of any one of the busbars 71, 72, and 73 overlaps in the first direction Z, and at least a portion of any one of the busbars 71, 72, and 73 overlaps in the second direction X. In this case, the busbar unit 70 can be brought closer to the fourth flow path section 94 in the first direction Z and the second direction X, making it easier to miniaturize the busbar housing space A4.

[0091] As shown in Figure 3, the drive unit 100 of this embodiment includes a cooler 8 housed in the control unit housing space A1 and connected to the fourth flow path section 94. When viewed from the first direction Z, the cooler 8 overlaps with the fourth flow path section 94 in the axial direction Y. Therefore, the drive unit 100 can be miniaturized in the second direction X. Furthermore, according to this embodiment, it is easier to arrange the cooler 8 and the fourth flow path section 94 closer together in the axial direction Y. Therefore, the flow path length of the flow path between the cooler 8 and the fourth flow path section 94 (the second flow path section 92 in this embodiment) can be shortened, and the pressure loss in the flow path 90 can be reduced. In this embodiment, the cooler 8 is connected to the fourth flow path section 94 via the second flow path section 92, but the cooler 8 may also be directly connected to the fourth flow path section 94. In this case, it is easier to further reduce the pressure loss in the flow path 90.

[0092] As shown in Figure 4, at least a portion of the busbar housing space A4 in this embodiment overlaps with the control unit housing space A1 in the axial direction Y. Furthermore, at least a portion of the busbar housing space A4 overlaps with the control unit housing space A1 in the first direction Z. According to this embodiment, it becomes easier to reduce the distance between the busbar housing space A4 and the control unit housing space A1. As a result, the control unit busbar 7a that extends across the control unit housing space A1 and the busbar housing space A4 can be shortened, and the electrical resistance of the control unit busbar 7a can be reduced. In addition, the path of the flow path (second flow path section 92) that extends across the control unit housing space A1 and the busbar housing space A4 can be shortened, and the pressure loss of the flow path 90 can be reduced.

[0093] As shown in Figure 3, in the drive unit 100 of this embodiment, the fourth flow path section 94, the first housing section 6A, and the second housing section 6B are arranged side by side in the axial direction Y. According to this embodiment, the drive unit 100 can be miniaturized in the first direction Z and the second direction X.

[0094] Furthermore, in the drive unit 100 of this embodiment, the fourth flow path section 94, the control unit housing space A1, and the gear housing space A2 are arranged side by side in the axial direction Y when viewed from the first direction Z. According to this embodiment, the drive unit 100 can be miniaturized in the second direction X.

[0095] As shown in Figure 2, the busbar housing space A4 in this embodiment is located on one side (+Z) of the output shaft 55 in the first direction. Therefore, in this embodiment, the bracket 69 supporting the output shaft 55 overlaps with the busbar housing space A4 in the first direction Z. According to this embodiment, the bracket 69 can be prevented from protruding in the axial direction Y and the second direction X relative to the busbar housing space A4, and the drive unit 100 can be miniaturized in the axial direction Y and the second direction X. In addition, the bracket 69 in this embodiment also overlaps with the fourth flow path section 94 and the busbar unit 70, which are located in the busbar housing space A4, in the first direction Z.

[0096] <Variation> Next, we will describe some modifications that can be adopted in the above-described embodiments. In the descriptions of each modification below, components that are identical in form to those of the embodiments or modifications already described will be denoted by the same reference numerals, and their descriptions will be omitted.

[0097] (Variation 1) Figure 6 is a front view showing the busbar unit 170 and the fourth flow channel section 94 of the modified example 1. The fourth flow path section 94 of this modified example differs from the embodiment described above mainly in that it passes through the inside of the busbar unit 170.

[0098] The busbar unit 170 in this modified example is arranged in the busbar housing space A4, similar to the embodiment described above, and electrically connects the motor 2 and the control unit 7 (see Figure 3). The busbar unit 170 in this modified example has a plurality of busbars 171, 172, 173 and a busbar holder 175, similar to the embodiment described above.

[0099] The modified busbar holder 175 has a holder body portion 175g, a first fixing portion 175a, a second fixing portion 175b, a pipe portion 175p, and a connecting plate portion 175q.

[0100] The holder body 175g encompasses and holds multiple busbars 171, 172, and 173. The first fixing part 175a and the second fixing part 175b are provided with through holes that penetrate in the axial direction Y. Fixing bolts 76 for fixing the busbar unit 170 to the housing 6 are inserted into the through holes.

[0101] The pipe section 175p is located on the other side (-Z) of the holder body 175g in the first direction. The pipe section 175p is also located on the other side (-Z) of the multiple busbars 171, 172, and 173 held by the holder body 175g. The pipe section 175p extends in the axial direction Y.

[0102] Similar to the embodiment described above, the fourth flow path 94 passes inside the pipe section 175p. The other axial end (-Y) of the pipe section 175p is inserted into the partition wall section 66d, and the other axial end (+Y) is inserted into the motor cover 61 (see Figure 3).

[0103] The connecting plate portion 175q is plate-shaped and extends along a plane perpendicular to the axial direction Y. The connecting plate portion 175q extends from the holder body portion 175g in the other direction (-Z). The connecting plate portion 175q is also connected to the outer circumferential surface of the pipe portion 175p. Therefore, the connecting plate portion 175q connects the holder body portion 175g and the pipe portion 175p.

[0104] In this modified configuration, the fourth flow channel 94 penetrates the busbar unit 170 in the axial direction Y. In this modified configuration, the busbar unit 170 and the fourth flow channel 94 can be brought closer together within the busbar housing space A4, making it easier to reduce the size of the busbar housing space A4. In this modified configuration, the fourth flow channel 94 is located on the other side (-Z) in the first direction relative to all the busbars 171, 172, and 173 of the busbar unit 170. However, the fourth flow channel 94 may be positioned between the busbars in the first direction Z.

[0105] In this specification, "the fourth flow channel 94 penetrates the busbar unit 170 in the axial direction Y" means that at least a portion of the fourth flow channel 94 is surrounded by the busbar unit 170 from a direction intersecting the axial direction Y. The portion of the busbar unit 170 surrounding the fourth flow channel 94 may be the busbar holder 175 or any of the busbars 171, 172, or 173.

[0106] In this modified example, the pipe section 175p, which is provided with the fourth flow path section 94, and the busbar holder 175 are a single component. That is, the pipe section 175p is part of the busbar holder 175. According to this modified example, the busbar holder 175 and the busbars 171, 172, and 173 can be cooled by the fluid O flowing through the fourth flow path section 94. Note that the pipe section 175p and the busbar holder 175 may be separate components.

[0107] (Modification 2) Figure 7 is a schematic diagram showing the arrangement of the busbar 273 and the fourth flow channel 94 in modified example 2. Note that the busbar holder that holds the busbar 273 is not shown in Figure 7.

[0108] In this modified example, the busbar 273 has a first portion 273z extending in a first direction Z and a second portion 273x extending in a second direction X. The end of the first portion 273z on the other side (-Z) in the first direction is connected to the end of the second portion 273x on one side (+X) in the second direction. That is, the shape of the busbar 273 when viewed from the axial direction Y is L-shaped.

[0109] In this modified example, the busbar 273 overlaps the fourth flow path 94 in the second direction X in the first portion 273z, and overlaps the fourth flow path 94 in the first direction Z in the second portion 273x. Therefore, a portion of the busbar unit 270 having the busbar 273 overlaps the fourth flow path 94 in the first direction Z when viewed from the axial direction Y, and another portion of the busbar unit 270 overlaps the fourth flow path 94 in the second direction X when viewed from the axial direction Y. In this modified example as well, it becomes easier to reduce the distance between the busbar unit 270 and the fourth flow path 94, making it easier to miniaturize the busbar housing space A4.

[0110] (Variation 3) Figure 8 is a schematic diagram showing the arrangement of the busbar 373 and the fourth flow channel 94 in modified example 3. Note that the busbar holder that holds the busbar 373 is not shown in Figure 8.

[0111] In this modified example, the busbar 373 has a first portion 373za extending in a first direction Z, a second portion 373x extending in a second direction X, and a third portion 373zb extending in a first direction Z. The end of the first portion 373za on the other side (-Z) in the first direction connects to the end of the second portion 373x on one side (+X) in the second direction. The end of the third portion 373zb on the other side (-Z) in the first direction connects to the end of the second portion 373x on the other side (-X) in the second direction. In other words, the shape of the busbar 373 when viewed from the axial direction is U-shaped.

[0112] In this modified example, pipe 94A is positioned between the first portion 373za and the third portion 373zb. Therefore, the busbar 373 in this modified example overlaps with the fourth flow path 94 in the second direction X in the first portion 373za and the third portion 373zb, and overlaps with the fourth flow path 94 in the first direction Z in the second portion 373x. As a result, a portion of the busbar unit 370 having the busbar 373 overlaps with the fourth flow path 94 in the first direction Z when viewed from the axial direction Y, and another portion of the busbar unit 370 overlaps with the fourth flow path 94 in the second direction X when viewed from the axial direction Y. In this modified example as well, it becomes easier to reduce the distance between the busbar unit 370 and the fourth flow path 94, making it easier to miniaturize the busbar housing space A4. Furthermore, similar to the modified example described above, when the fourth flow channel 94 penetrates the busbar unit 370 in the axial direction Y, the busbar 373 is easily cooled because the fourth flow channel 94 and the respective parts of the busbar 373 (first part 373za, second part 373x, third part 373zb) are close together.

[0113] Although embodiments and variations of the present invention have been described above, the configurations and combinations thereof in the embodiments and variations are merely examples, and additions, omissions, substitutions, and other modifications are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited by the embodiments.

[0114] For example, in the embodiments described above, a case in which the drive unit includes a power transmission unit was described, but a drive unit without a power transmission unit is also conceivable. Furthermore, even when a power transmission unit is included, the structure of the power transmission unit is not limited to the embodiments described above. For example, the power transmission unit may not have a second shaft, a second gear, and a third gear, and the first gear and the ring gear may mesh together. Also, in the embodiments and their modifications described above, a case in which the busbar unit includes multiple busbars was described, but the busbar unit may include only one busbar.

[0115] Furthermore, this technology can be configured as follows: (1) A motor having a rotor that can rotate about a central axis and a stator facing the rotor, A control unit for controlling the motor, A busbar unit having a busbar that electrically connects the motor and the control unit, The housing comprises a motor housing space in which the motor is housed, a control unit housing space in which the control unit is housed, and a busbar housing space in which the busbar unit is housed. The aforementioned housing is A motor cover located on one axial side of the motor housing space, A partition wall separates the busbar housing space and the control unit housing space, It has a connecting channel that connects the partition wall and the motor cover and is located in the busbar housing space, Two directions that are perpendicular to the axial direction and also perpendicular to each other are defined as the first and second directions. The busbar housing space is a space continuous with the motor housing space, and is located on one side of the motor housing space in the second direction. The busbar unit is a drive device that, when viewed from the axial direction, overlaps the connecting flow path in the first direction with the connecting flow path. (2) A portion of the busbar unit, when viewed from the axial direction, overlaps with the connecting flow channel portion in the first direction, Another part of the busbar unit, when viewed from the axial direction, overlaps the connecting flow path portion with the drive device described in (1) in the second direction. (3) A cooler connected to the connecting channel section and housed in the control unit housing space, The cooler is the drive device according to (1) or (2), which, when viewed from the first direction, overlaps the connecting flow path in the axial direction with the cooler. (4) A power transmission unit that transmits power from the motor, The aforementioned housing is A first housing unit having the aforementioned control unit housing space inside, It has a second housing section having a space inside which the power transmission section is housed, The drive device according to (1) to (3), wherein the connecting channel section, the first housing section, and the second housing section are arranged in the axial direction. (5) A power transmission unit that transmits power from the motor, A bracket supporting the output shaft connected to the power transmission section is provided on the outer surface of the housing. The drive device according to (1) to (3), wherein the bracket overlaps with the busbar housing space in a first direction. (6) A bracket is provided on the outer surface of the housing to support the output shaft connected to the power transmission section, The drive device according to (4), wherein the bracket overlaps with the busbar housing space in a first direction. (7) The connecting channel portion is a drive device according to any one of (1) to (6) that penetrates the busbar unit in the axial direction. [Explanation of Symbols]

[0116] 2…Motor, 3…Power transmission unit, 6…Housing, 6A…First housing unit, 6B…Second housing unit, 7…Control unit, 8…Cooler, 20…Rotor, 25…Stator, 55…Output shaft, 61…Motor cover, 66d…Bulkhead unit, 69…Bracket, 70, 170, 270…Busbar unit, 71, 72, 73, 171, 172, 173, 273, 373…Busbar, 90…Flow path, 94…Fourth flow path unit (connecting flow path unit), 100…Drive unit, A1…Control unit housing space, A3…Motor housing space, A4…Busbar housing space, J1…First axis (center axis), X…Second direction, Y…Axial direction, Z…First direction

Claims

1. A motor having a rotor that can rotate about a central axis, and a stator facing the rotor, A control unit for controlling the motor, A busbar unit having a busbar that electrically connects the motor and the control unit, The housing comprises a motor housing space in which the motor is housed, a control unit housing space in which the control unit is housed, and a busbar housing space in which the busbar unit is housed. The aforementioned housing is A motor cover located on one axial side of the motor housing space, A partition wall separates the busbar housing space and the control unit housing space, It has a connecting channel that connects the partition wall and the motor cover and is located in the busbar housing space, Two directions that are perpendicular to the axial direction and also perpendicular to each other are defined as the first and second directions. The busbar housing space is a space continuous with the motor housing space, and is located on one side of the motor housing space in the second direction. The busbar unit, when viewed from the axial direction, overlaps with the connecting flow path in the first direction. Drive unit.

2. A portion of the busbar unit, when viewed from the axial direction, overlaps with the connecting channel portion in the first direction. Another part of the busbar unit, when viewed from the axial direction, overlaps with the connecting flow path in the second direction. The drive device according to claim 1.

3. The cooler is connected to the aforementioned connecting channel and housed in the control unit housing space, The cooler, when viewed from the first direction, overlaps the connecting flow path in the axial direction with the cooler. The drive device according to claim 1 or claim 2.

4. It includes a power transmission unit that transmits power from the motor, The aforementioned housing is A first housing unit having the aforementioned control unit housing space inside, It has a second housing section which has a space inside which the power transmission section is housed, The connecting channel section, the first housing section, and the second housing section are arranged side by side in the axial direction. The drive device according to claim 1.

5. It includes a power transmission unit that transmits power from the motor, A bracket supporting the output shaft connected to the power transmission section is provided on the outer surface of the housing. The bracket overlaps with the busbar housing space in a first direction. The drive device according to claim 1.

6. The aforementioned connecting channel portion penetrates the busbar unit in the axial direction. The drive device according to claim 1.

Images