Drive unit

Abstract

The present invention provides a drive device capable of cooling multiple objects, including busbars. [Solution] 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 busbar unit 70 having a busbar connected to the motor and a busbar holder 75 supporting the busbar, and a housing housing the motor and the busbar unit. The housing is provided with a first housing passage through which fluid can flow. The busbar holder is provided with a holder passage 80. The holder passage has a first end 80a directly or indirectly connected to the first housing passage 92 and a second end 80b opening to the outside of the busbar holder.

Description

Technical Field

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

Background Art

[0002] In recent years, as drive devices for electric vehicles and the like, drive devices including a motor and an inverter connected to the motor have been developed. Such a drive device is provided with bus bars that electrically connect the motor and the inverter. Patent Document 1 discloses a structure in which bus bars are arranged in a case having a refrigerant flow path and the bus bars are cooled by a refrigerant.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The drive device has a plurality of objects to be cooled in addition to the bus bars. For this reason, there has been a problem that if the fluid supplied to the bus bars is used only for cooling the bus bars, the entire drive device cannot be cooled efficiently.

[0005] In view of the above circumstances, one object of the present invention is to provide a drive device capable of cooling a plurality of objects to be cooled including bus bars.

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 busbar unit having a busbar connected to the motor and a busbar holder supporting the busbar; and a housing housing the motor and the busbar unit. The housing is provided with a first housing passage through which fluid can flow. The busbar holder is provided with a holder passage. The holder passage has a first end directly or indirectly connected to the first housing passage and a second end opening to the outside of the busbar holder. [Effects of the Invention]

[0007] According to one aspect of the present invention, it becomes possible to supply the fluid used to cool the busbar to other objects to be cooled, thereby enabling the cooling of multiple objects, including the busbar. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic diagram showing the general outline of a drive device according to one embodiment. [Figure 2] Figure 2 is a perspective view of a busbar unit according to one embodiment. [Figure 3] Figure 3 is a front view of a busbar unit according to one embodiment. [Figure 4] Figure 4 is a schematic cross-sectional view of a busbar unit according to one embodiment. [Figure 5] Figure 5 is a front view of the busbar unit of Modification 1, and also, [Figure 6] Figure 6 is a schematic cross-sectional view of the busbar unit of the modified example 1. [Figure 7] Figure 7 is a front view of the busbar unit of Modified Example 2. [Modes for carrying out the invention]

[0009] The following description of a drive unit according to one embodiment of the present invention will be given 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) FIG. 1 is a schematic diagram showing an outline of a drive device 100 according to an embodiment. The drive device 100 of the present embodiment is mounted on a vehicle that uses a motor as a power source, such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHV), and an electric vehicle (EV), and is used as the power source thereof.

[0014] As shown in FIG. 1, the drive device 100 includes a motor 2, a power transmission unit 3, a control unit 7, a bus bar unit 70, a housing 6, a pump 9, and a cooler 8. Further, the drive device 100 is provided with a flow passage 90.

[0015] (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.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] The stator 25 radially faces the rotor 20. The stator 25 surrounds the rotor 20 from the radial 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 busbar unit 70. The coil 26 has a pair of coil ends 26e protruding in the axial direction Y from both end faces of the stator core 27 in the axial direction Y, respectively.

[0020] (Power Transmission Unit) As shown in FIG. 1, the power transmission unit 3 is located on the other axial side (-Y) of the motor 2. The power transmission unit 3 transmits the power of the motor 2. The power transmission unit 3 is connected to the rotor 20. A pair of output shafts 55 are connected to the power transmission unit 3. The power transmission unit 3 decelerates or accelerates the rotation of the rotor 20 and transmits the rotation to the output shafts 55.

[0021] 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 device 5.

[0022] The first shaft 44 extends in the axial direction Y around the first axis J1. The first shaft 44 is rotatable around the first axis J1. The first shaft 44 is coupled to the end portion on the other axial side (-Y) of the motor shaft 21 at the end portion on one axial side (+Y), and rotates together with the rotor 20. The first shaft 44 and the motor shaft 21 may be a single member, and the first shaft 44 and the motor shaft 21 may be part of that single member. The first gear 41 is provided on the outer peripheral surface of the first shaft 44. The first gear 41 rotates together with the rotor 20 around the first axis J1.

[0023] 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.

[0024] 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.

[0025] (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.

[0026] (housing) As shown in Figure 1, the housing 6 accommodates the motor 2, power transmission unit 3, control unit 7, and busbar unit 70. The housing 6 is provided with a motor housing space A3 for housing the motor 2, a control unit housing space A1 for housing the control unit 7 and cooler 8, a gear housing space A2 for housing the power transmission unit 3, and a busbar housing space A4 for housing the busbar unit 70.

[0027] The housing 6 comprises a housing body 60, a motor cover 61, and a gear cover 62. In this embodiment, the housing body 60, the motor cover 61, and the gear cover 62 are separate components. The motor cover 61 is positioned on one axial side (+Y) of the housing body 60. The gear cover 62 is positioned on the other axial side (-Y) of the housing body 60.

[0028] The housing body 60 includes a cylindrical wall portion 60a, an expanded wall portion 66, a control unit case 64, and a gear case 65. The cylindrical wall portion 60a is substantially cylindrical with the first axis J1 as its center. The cylindrical wall portion 60a surrounds the motor 2 from the radially outer side. 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, along 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.

[0029] The motor 2 is housed in the space enclosed by the cylindrical wall 60a and the motor cover 61. In other words, the motor housing space A3 is the internal space enclosed by the cylindrical wall 60a and the motor cover 61. The busbar unit 70 is arranged in the space enclosed by the extension wall 66 and the motor cover 61. In other words, the busbar housing space A4 is the internal space enclosed by the extension wall 66 and the motor cover 61.

[0030] There is no wall between the busbar housing space A4 and the motor housing space A3. Therefore, the busbar housing space A4 and the motor housing space A3 are continuous spaces. The busbar housing space A4 is located on one side (+X) of the motor housing space A3 in the second direction. The busbar housing space A4 extends from the motor housing space A3 in one side (+X) in the second direction.

[0031] The extension wall 66 has a partition wall 66d located on the other axial side (-Y) of the busbar housing space A4. The partition wall 66d is located between the busbar housing space A4 and the control unit housing space A1 in the axial direction Y. The partition wall 66d divides the busbar housing space A4 and the control unit housing space A1 in the axial direction Y.

[0032] The partition wall 66d and the motor cover 61 face each other in the axial direction Y. The partition wall 66d is provided with an internal housing branch 92a, which will be described later. The internal housing branch 92a is a recess provided on the surface of the partition wall 66d facing one axial side (+Y) and opening to the axial side (+Y). The motor cover 61 is also provided with a recess 95A, which will be described later. The recess 95A is provided on the surface of the motor cover 61 facing the other axial side (-Y) and opening to the other axial side (-Y).

[0033] 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 inserted into the first fixing portion 75a and the second fixing portion 75b of the busbar holder 75, which will be described later, are tightened into the two screw holes.

[0034] The gear case 65 has a concave shape that opens to the other axial side (-Y). The opening of the gear case 65 is covered by the gear cover 62. The gear cover 62 has a concave shape that opens to one axial side (+Y). The gear case 65 and the gear cover 62 are connected with their openings facing each other. The power transmission unit 3 is housed in the space enclosed by the gear case 65 and the gear cover 62. In other words, the gear housing space A2 is the internal space enclosed by the gear case 65 and the gear cover 62.

[0035] 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, with its opening covered by, for example, a lid member (not shown). Inside the control unit case 64, a control unit housing space A1 is provided. The control unit housing space A1 is located radially outward from the motor housing space A3. The control unit housing space A1 is located on the other axial side (-Y) of the busbar housing space A4.

[0036] (Bus bar unit) Figure 2 is a perspective view of the busbar unit 70 of this embodiment. Figure 3 is a front view of the busbar unit 70 of this embodiment.

[0037] As shown in Figure 3, the busbar unit 70 has a plurality of busbars 71, 72, and 73 (three in this embodiment) and a busbar holder 75 that holds the plurality of busbars 71, 72, and 73.

[0038] 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.

[0039] The busbars 71, 72, and 73 are made of plate-shaped conductive members. For example, metallic materials with high electrical conductivity, such as copper, can be used for the busbars 71, 72, and 73. 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. The multiple busbars 71, 72, and 73 each electrically connect the motor 2 and the control unit 7.

[0040] 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, respectively.

[0041] Multiple busbar body sections 71c, 72c, and 73c connect the first connection ends 71a, 72a, and 73a to 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 a busbar holder 75 and supported by the busbar holder 75.

[0042] The three first connecting ends 71a, 72a, and 73a are located at the end of the bus bar 71, 72, and 73 on the other side of the second direction (-X). The three first connecting ends 71a, 72a, and 73a are each exposed from the bus bar holder 75. The thickness direction of the three first connecting ends 71a, 72a, and 73a each coincides with the axial direction Y. The three first connecting ends 71a, 72a, and 73a are arranged in a direction that inclins toward the other side of the first direction (-Z) as it moves toward the other side of the second direction (+X). The three first connecting ends 71a, 72a, and 73a each extend in a direction that inclins toward the other side of the first direction (-Z) as it moves toward the other side of the second direction (-X).

[0043] As shown in Figure 2, the three first connecting ends 71a, 72a, and 73a are each connected to a terminal member 26a extending from the motor 2. 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 to overlap on one axial side (+Y) of the terminal member 26a. Alternatively, the three first connecting ends 71a, 72a, and 73a may each be arranged to overlap on the other axial side (-Y) of the terminal member 26a.

[0044] As shown in Figure 3, the three first connecting ends 71a, 72a, and 73a are each provided with through holes 70a that penetrate in the thickness direction, and the three terminal members 26a are each provided with through holes 26h that penetrate in the thickness direction. Bolts (not shown) are inserted into the through holes 70a of the overlapping first connecting ends 71a, 72a, and 73a and the through holes 26h of the terminal members 26a. 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. By tightening the bolts into the nuts, the three first connecting ends 71a, 72a, and 73a are electrically connected to the terminal member 26a.

[0045] As shown in Figure 2, the second connecting ends 71b, 72b, and 73b are located at the end of each bus bar 71, 72, and 73 on one side (+X) in the second direction. The three second connecting ends 71b, 72b, and 73b are each exposed from the bus bar 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.

[0046] The three second connection ends 71b, 72b, and 73b are each connected to the control bus bar 7a extending from the control unit 7. The thickness direction of the second connection 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 connection ends 71b, 72b, and 73b are each arranged to overlap on the other axial side (-Y) of the control bus bar 7a. Alternatively, the three second connection ends 71b, 72b, and 73b may each be arranged to overlap on one axial side (+Y) of the control bus bar 7a.

[0047] As shown in Figure 3, the second connecting ends 71b, 72b, and 73b are each provided with through holes 70b that penetrate in the thickness direction, and the three control bus bars 7a are each provided with through holes 7h that penetrate in the thickness direction. Bolts (not shown) are inserted into the through holes 70b of the overlapping second connecting ends 71b, 72b, and 73b and the through holes 7h of the control bus bars 7a. The bolts are tightened into nuts (not shown) located on the other axial side (-Y) of the second connecting ends 71b, 72b, and 73b. As a result, the three second connecting ends 71b, 72b, and 73b are electrically connected to the control bus bars 7a.

[0048] In the following description, when distinguishing between the three busbars 71, 72, and 73, they will be referred to as the first busbar 71, the second busbar 72, and the third busbar 73. Note that the shape (e.g., direction of extension), arrangement of each busbar 71, 72, and 73 included in the busbar unit 70, and the number of busbars 71, 72, and 73 are not limited to this embodiment.

[0049] As shown in Figure 2, in this embodiment, the busbar body portion 73c of the third busbar 73 is bent in the axial direction Y. The busbar body portion 73c of the third busbar 73 extends in a direction that tilts toward the other side of the first direction (-Z) as it moves toward the other side of the second direction (-X) when viewed from the axial direction Y. The first connecting end 73a of the third busbar 73 extends from the end of the busbar body portion 73c toward the other side of the second direction (-X) in a direction that tilts toward the other side of the first direction (-Z) as it moves toward the other side of the second direction (-X). The second connecting end 73b of the third busbar 73 extends toward the other side of the second direction (+X) from the end of the busbar body portion 73c toward the other side of the second direction (+X).

[0050] 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 in a direction that inclins toward the other axial side (-Z) from the end of the busbar body portion 72c toward the other axial side (-X) toward the other axial side (-X). The second connecting end 72b of the second busbar 72 extends toward the other axial side (+X) from the end of the busbar body portion 72c toward the other axial side (+X).

[0051] 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 portions 72c and 73c of the second busbar 72 and 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 in a direction that inclins toward the other axial side (-Z) from the end of the busbar body portion 71c toward the other axial side (-X) toward the other axial 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 other side (+X).

[0052] The busbar holder 75 holds the busbar body portions 71c, 72c, and 73c of multiple busbars 71, 72, and 73. The busbar holder 75 is made of a highly insulating resin material or the like.

[0053] 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.

[0054] The busbar holder 75 includes a holder body portion 75g, a first fixing portion 75a, a second fixing portion 75b, a connecting plate portion 76, and a pipe portion 77.

[0055] As shown in Figure 2, in the axial direction Y, the thickness of the holder body 75g is greater than the combined thickness of at least three busbars 71, 72, and 73 aligned in the axial direction Y. The holder body 75g holds the multiple busbars 71, 72, and 73. Multiple (three in this embodiment) retaining recesses 75h are provided on the surface of the holder body 75g facing one side in the first direction (+Z). Retaining recesses 75h are located on the other axial side (-Y) of each second connection end 71b, 72b, and 73b. Each retaining recess 75h accommodates a nut (not shown) used for fastening the second connection end 71b, 72b, and 73b to the control unit busbar 7a.

[0056] 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 in one direction (+X) in the second direction. The second fixing portion 75b protrudes from the holder body portion 75g in the other direction (-Z) in the first direction. The first fixing portion 75a and the second fixing portion 75b are provided with through holes 75ah and 75bh, respectively, that penetrate in the axial direction Y. Fixing bolts (not shown) for fixing the busbar unit 70 to the housing 6 are inserted into the through holes 75ah and 75bh. Alternatively, cylindrical collar members extending in the axial direction Y may be placed in the through holes 75ah and 75bh, respectively. In this case, the fixing bolts (not shown) are inserted into the collar members. Furthermore, both end faces of the collar member in the axial direction Y contact the fixing bolts and the housing 6, respectively. Since the fixing bolts 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. However, by providing collar members in the through holes 75ah and 75bh, the stress applied to the busbar holder 75 by the fastening of the fixing bolts can be suppressed, and the busbar holder 75 can be protected from deformation, breakage, and other damage.

[0057] The pipe section 77 is located on the other side (-Z) of the holder body 75g in the first direction. The pipe section 77 is also located on the other side (-Z) of the multiple busbars 71, 72, and 73 held by the holder body 75g in the first direction. The pipe section 77 is a cylindrical body extending in the axial direction Y. The pipe section 77 has a first pipe end 77a on the other side (-Y) in the axial direction and a second pipe end 77b on the one side (+Y) in the axial direction. Inside the pipe section 77 is provided the first holder flow path section 81, which will be described later.

[0058] The connecting plate portion 76 is plate-shaped and extends along a plane perpendicular to the axial direction Y. The connecting plate portion 76 extends from the holder body portion 75g in the other direction (-Z) of the first direction. The connecting plate portion 76 connects the holder body portion 75g and the outer circumferential surface of the pipe portion 77.

[0059] <Flow path> As shown in Figure 1, the drive unit 100 is provided with a flow path 90 through which fluid O circulates. The flow path 90 includes a first housing flow path section 91, a second housing flow path section (first housing flow path) 92, a third housing flow path section 93, a fourth housing flow path section (second housing flow path) 94, and a holder flow path 80.

[0060] In this embodiment, fluid O functions as a coolant to cool the heat-generating parts of the drive unit 100. Fluid O may also function as a lubricant to lubricate bearings and power transmission parts 3, etc. As fluid O, for example, an oil equivalent to a relatively low-viscosity automatic transmission fluid (ATF) can be used.

[0061] The first housing flow channel 91, the second housing flow channel 92, the third housing flow channel 93, and the fourth housing flow channel 94 are holes provided within the wall of the housing 6. That is, the housing 6 is provided with the first housing flow channel 91, the second housing flow channel 92, the third housing flow channel 93, and the fourth housing flow channel 94 through which the fluid O can flow. The holder flow channel 80 is a flow channel that passes through the inside of the busbar holder 75. That is, the busbar holder 75 is provided with the holder flow channel 80.

[0062] Furthermore, a pump 9 and a cooler 8 are provided in the path of the flow path 90. The pump 9 sucks up the fluid O that accumulates at the bottom of the gear housing space A2 and supplies it to the first housing flow path section 91.

[0063] The first housing flow channel 91 connects the pump 9 and the cooler 8. The cooler 8 is housed in the control unit housing space A1. The cooler 8 cools the fluid O supplied from the first housing flow channel 91.

[0064] The second housing flow path section 92 extends axially in one direction (+Y) from the outlet of the cooler 8 and connects to the internal housing branch section 92a provided in the partition wall section 66d.

[0065] The second housing flow channel 92, the third housing flow channel 93, and the holder flow channel 80 are connected to the internal branching section 92a of the housing. The fluid O flowing through the second housing flow channel 92 branches at the internal branching section 92a into the third housing flow channel 93 and the holder flow channel 80. The first pipe end 77a of the pipe section 77 is inserted into the opening of the internal branching section 92a. The second housing flow channel 92 and the third housing flow channel 93 open at the bottom of the internal branching section 92a.

[0066] The third housing flow path section 93 extends from the internal housing branch section 92a in the other axial direction (-Y). The third housing flow path section 93 connects the internal housing branch section 92a to the motor housing space A3. The downstream end of the third housing flow path section 93 opens into the motor housing space A3 on the other axial direction (-Y) of the motor 2. The fluid O is discharged from the third housing flow path section 93 toward the motor 2.

[0067] The holder channel 80 is located in the busbar housing space A4. The holder channel 80 has a first holder channel section (first channel section) 81 and a second holder channel section (second channel section) 82.

[0068] The first holder flow path 81 extends axially Y inside the pipe section 77. The first holder flow path 81 has a first end 80a, a third end 80c, and a first holder internal branch 80g. That is, the holder flow path 80 has a first end 80a, a third end 80c, and a first holder internal branch 80g. The first end 80a is located at the first pipe end 77a of the pipe section 77. The second end 80b is located at the second pipe end 77b of the pipe section 77. The first holder internal branch 80g is located between the first end 80a and the third end 80c in the axial direction Y. The first holder flow path 81 is a flow path that linearly connects the first end 80a and the third end 80c. Furthermore, the first holder flow channel 81 may have a curved or bent portion between the first end 80a and the third end 80c, provided that it is connected to the first end 80a and the third end 80c.

[0069] As shown in Figure 1, the first pipe end 77a of the pipe section 77 is inserted into the internal branching section 92a of the partition wall section 66d, so the first end 80a is connected to the second housing flow path section 92. Also, the second pipe end 77b of the pipe section 77 is inserted into the recess 95A provided in the motor cover 61, so the third end 80c is connected to the fourth housing flow path section 94. The first holder flow path section 81 connects the third housing flow path section 93 and the fourth housing flow path section 94.

[0070] It is preferable to place O-rings on the outer circumferential surfaces of the first pipe end 77a and the second pipe end 77b, respectively. This prevents the fluid O in the branch section 92a inside the housing from leaking into the busbar housing space A4.

[0071] As shown in Figure 2, the second holder flow path portion 82 is provided in the connecting plate portion 76 and the holder body portion 75g of the busbar holder 75. In this embodiment, the second holder flow path portion 82 is a hole provided in the busbar holder 75. The second holder flow path portion 82 may also be, for example, a groove provided in the busbar holder 75.

[0072] The second holder channel section 82 is connected to the first holder internal branch section 80g of the first holder channel section 81. In other words, the second holder channel section 82 branches off from the first holder channel section 81. The second holder channel section 82 also has a second end 80b that opens to the outside of the busbar holder 75. In other words, the holder channel 80 has a second end 80b. The second end 80b is provided on the upper surface 75f of the holder body section 75g facing one side (+Z) in the first direction. The second end 80b may also open on a surface other than the upper surface 75f of the busbar holder 75. The second holder channel section 82 is a channel that linearly connects the first holder internal branch section 80g of the first holder channel section 81 and the second end 80b. Furthermore, the second holder flow path 82 may have a curved or bent portion between the first holder internal branch 80g and the second end portion 80b, provided that it is connected to the first holder internal branch 80g and the second end portion 80b. In this embodiment, the second holder flow path 82 extends from the first holder internal branch 80g toward the other side in the second direction (-X) toward one side in the first direction (+Z). However, the direction in which the second holder flow path 82 extends is not limited to this embodiment.

[0073] The second holder flow channel 82 extends at the second end 80b in one direction (+Z) and the other direction (-X) in the first direction. Therefore, the fluid O flowing through the second holder flow channel 82 toward the second end 80b flows out from the second end 80b in one direction (+Z) and the other direction (-X).

[0074] As shown in Figure 1, the busbar unit 70 of this embodiment is located radially outward of the motor 2 and on one side in the second direction (+X). In particular, the busbar unit 70 of this embodiment is located radially outward of the coil end 26e. Furthermore, the busbar housing space A4 in which the busbar unit 70 is arranged is located on one side in the second direction (+X) of the motor housing space A3. The fluid O flowing through the second holder flow path 82 flows out from the second end 80b toward the motor housing space A3. Furthermore, the second end 80b is located on one side in the second direction (+X) of the coil end 26e. A portion of the fluid O flowing out from the second end 80b is supplied to the coil end 26e to cool it. According to this embodiment, the heat-generating part of the motor 2 can be cooled by the fluid O flowing through the holder flow path 80. The fluid O flowing out from the second end 80b may reach the coil end 26e directly from the second end 80b, or it may reach the coil end 26e after hitting other components such as the inner wall surface of the housing 6.

[0075] Figure 4 is a schematic cross-sectional view of the busbar unit 70, including a cross-section of the second holder channel 82. As shown in Figure 4, the cross-sectional shape of the second holder channel 82 in this embodiment is rectangular. However, the cross-sectional shape of the second holder channel 82 may be other shapes, such as circular.

[0076] In this embodiment, the second holder flow path 82 is located in the axial direction Y between the busbar body portion 72c of the second busbar 72 and the busbar body portion 73c of the third busbar 73. According to this embodiment, the second busbar 72 and the third busbar 73 can be cooled by the fluid O flowing through the second holder flow path 82.

[0077] In this embodiment, at least a portion of the busbar body portion 72c of the second busbar 72 is exposed to the internal space of the second holder flow path portion 82. That is, the second busbar 72 constitutes at least a portion of the inner surface of the second holder flow path portion 82. Therefore, the fluid O flowing through the second holder flow path portion 82 comes into direct contact with the second busbar 72. According to this embodiment, at least one of the multiple busbars 71, 72, and 73 (the second busbar 72 in this embodiment) is exposed to the internal space of the holder flow path 80, thereby allowing the busbar to be effectively cooled by the fluid O.

[0078] Note that the busbars 71, 72, and 73 do not necessarily have to constitute the inner surface of the holder flow path 80. Even if the fluid O is not in direct contact with the busbars 71, 72, and 73, it receives heat from the busbars 71, 72, and 73 via the busbar holder 75, thereby cooling the busbars 71, 72, and 73.

[0079] As shown in Figure 1, the fourth housing flow path 94 is located inside the motor cover 61. The fourth housing flow path 94 extends radially inward from the recess 95A. That is, the fourth housing flow path 94 connects to the holder flow path 80. The fourth housing flow path 94 branches into multiple flow paths. That is, the fourth housing flow path 94 has multiple downstream ends. Some of the downstream ends of the fourth housing flow path 94 open into the motor housing space A3 on one axial side (+Y) of the motor 2. The fluid O is discharged from the fourth housing flow path 94 toward the motor 2. The other downstream ends of the fourth housing flow path 94 open toward the hollow portion 21h of the motor shaft 21. The fluid O supplied to the hollow portion 21h is guided, for example, to the rotor core 24 to cool the rotor core 24.

[0080] In the second holder flow path section 82, the third housing flow path section 93, and the fourth housing flow path section 94, the fluid O that flows out 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 through holes (not shown).

[0081] As shown in Figure 1, in the drive unit 100 of this embodiment, the holder flow path 80 provided in the busbar holder 75 has a first end 80a connected to the second housing flow path section 92 of the housing 6, and a second end 80b that opens to the outside of the busbar holder 75. According to this embodiment, the fluid O supplied from the second housing flow path section 92 of the housing 6 can be supplied to the inside of the busbar holder 75. This allows the busbars 71, 72, and 73 supported by the busbar holder 75 to be cooled. Furthermore, according to this embodiment, the fluid O supplied from the second housing flow path section 92 to the holder flow path 80 and flowing out from the second end 80b of the holder flow path 80 can be used to cool the motor 2 and the like. The fluid O flowing inside the housing 6 can be supplied to the object to be cooled via the holder flow path 80. Therefore, there is no need to provide a separate component from the busbar holder to supply fluid O to the motor. In other words, according to this embodiment, the holder flow path 80 can be used to cool multiple objects to be cooled, including the busbars 71, 72, and 73, and the entire drive unit 100 can be cooled efficiently.

[0082] In this embodiment, the holder flow path 80 has a first holder flow path section 81 that connects the second housing flow path section 92 and the fourth housing flow path section 94 of the housing 6, and a second holder flow path section 82 that branches off from the first holder flow path section 81. The second holder flow path section 82 also has a second end portion 80b that opens to the outside of the busbar holder 75. According to this embodiment, the first holder flow path section 81 connects the two flow paths of the housing 6 (the second housing flow path section 92 and the fourth housing flow path section 94). This allows the two flow paths of the housing 6 to be connected without having to bypass another part, such as the expanded wall section 66, and shortens the overall length of the flow path 90. As a result, the pressure loss in the flow path 90 can be reduced. Also, according to this embodiment, the second holder flow path section 82 branches off from the first holder flow path section 81 and extends to discharge the fluid O to the outside of the busbar holder 75. This allows a portion of the fluid O flowing through the housing 6 to be supplied to the object to be cooled.

[0083] In this embodiment, the case in which the first end 80a and the third end 80c are directly connected to the flow channels of the housing 6 (the second housing flow channel section 92 and the fourth housing flow channel section 94), respectively, has been described. However, the first end 80a and the third end 80c may also be connected to the flow channels of the housing 6 via other members. That is, the first end 80a may be directly or indirectly connected to the flow channel of the housing 6 (the second housing flow channel section 92). Similarly, the third end 80c may be directly or indirectly connected to the flow channel of the housing 6 (the fourth housing flow channel section 94).

[0084] Furthermore, as a modification of this embodiment, the pipe section 77 may be a separate component from the busbar holder 75. In this modification, only the second holder flow path section 82 constitutes the holder flow path 80. The first holder flow path section 81 connects the holder flow path 80 (second holder flow path section 82) and the second housing flow path section 92. In this modification, the holder flow path 80 (second holder flow path section 82) is indirectly connected to the second housing flow path section 92 via the first holder flow path section 81.

[0085] As shown in Figure 4, according to this embodiment, the busbar unit 70 has a plurality of busbars 71, 72, and 73. In addition, at least a portion of the holder flow path 80 (the second holder flow path portion 82) passes between one busbar (the second busbar 72) and another busbar (the third busbar 73) among the plurality of busbars 71, 72, and 73. According to this embodiment, by arranging a portion of the holder flow path 80 between two busbars 72 and 73, these busbars 72 and 73 can be efficiently cooled by the fluid O flowing through the holder flow path 80.

[0086] In this embodiment, at least a portion of the busbars 71, 72, and 73 are located inside the busbar holder 75. Also, at least a portion of the inner surface of the holder flow path 80 is formed by a busbar (in this embodiment, the second busbar 72). According to this embodiment, by arranging the busbars 71, 72, and 73 inside the busbar holder 75 by insert molding, it becomes possible to manage the multiple busbars 71, 72, and 73 and the busbar holder 75 as a single part. This facilitates part management and assembly processes. Furthermore, by forming the inner surface of the second holder flow path 82 with the second busbar 72, the fluid O flowing through the second holder flow path 82 can be brought into direct contact with the second busbar 72, thereby directly cooling the second busbar 72.

[0087] Furthermore, as shown by the dashed lines (two-dotted lines) in Figure 4, the inner surface of the second holder flow channel 82A may be composed of a second busbar 72 and a third busbar 73. In other words, the opposing inner surfaces of the holder flow channel may be composed of different busbars.

[0088] <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 the same as those in the embodiments already described will be denoted by the same reference numerals, and their descriptions will be omitted.

[0089] (Variation 1) Figure 5 is a front view of the busbar unit 170 of Modification 1. The busbar unit 170 of this modification differs from the embodiment described above mainly in the configuration of the holder flow path 180.

[0090] In this modified busbar unit 170, the motor 2 and the control unit 7 are electrically connected (see Figure 1). Similar to the embodiment described above, the busbar unit 170 in this modified version has a plurality of busbars 71, 72, and 73, and a busbar holder 175. The busbar holder 175 is also provided with a holder flow path 180.

[0091] The busbar holder 175 of this modified example has a guide portion 176 in addition to the holder body portion 75g, first fixing portion 75a, second fixing portion 75b, connecting plate portion 76, and pipe portion 77 similar to those in the above embodiment. Furthermore, the holder flow path 180 of this modified example has a third holder flow path portion (third flow path portion) 183 in addition to the first holder flow path portion 81 and second holder flow path portion 82 similar to those in the above embodiment.

[0092] The guide portion 176 is provided on the upper surface 75f of the holder body portion 75g facing one side in the first direction (+Z). The guide portion 176 is a rib that protrudes from the upper surface 75f in one side in the first direction (+Z) and extends along the second direction X. In this modified example, the guide portion 176 is located on the other axial side (-Y) of the second end 80b of the holder flow path 180 that opens at the upper surface 75f of the holder body portion 75g. The guide portion 176 guides the fluid O flowing out from the second end 80b to the upper side of the upper surface 75f to one side in the second direction (+X) and the other side in the second direction (-X).

[0093] On one side (+X) of the second end 80b in the second direction, the second connection ends 71b, 72b, and 73b of the busbars 71, 72, and 73, and the control busbar 7a of the control unit 7 connected to these second connection ends 71b, 72b, and 73b are arranged. The fluid O guided by the guide portion 176 to one side (+X) in the second direction is supplied, for example, to the second connection ends 71b, 72b, and 73b and the control busbar 7a, and cools the second connection ends 71b, 72b, and 73b and the control busbar 7a.

[0094] On the other side (-X) of the second end 80b in the second direction, the first connecting ends 71a, 72a, and 73a of the busbars 71, 72, and 73, along with terminal members 26a and coil ends 26e connected to these first connecting ends 71a, 72a, and 73a, are arranged. The fluid O guided to the other side (-X) in the second direction by the guide portion 176 is supplied, for example, to the first connecting ends 71a, 72a, and 73a, terminal members 26a, and coil ends 26e, cooling the first connecting ends 71a, 72a, and 73a, terminal members 26a, and coil ends 26e.

[0095] According to this modified example, the guide portion 176 directs the fluid O flowing out from the second end portion 80b to one side (+X) and the other side (-X) of the second direction, respectively. In other words, the guide portion 176 branches the path of the fluid O flowing out from the second end portion 80b. This makes it possible to supply fluid O to two cooling targets located in different directions from each other and cool these targets.

[0096] In this modified example, the third holder flow path 183 is provided on the holder body portion 75g of the busbar holder 175. The third holder flow path 183 has a fourth end portion 180d and a fifth end portion 180e. That is, the holder flow path 180 has a fourth end portion 180d and a fifth end portion 180e. Both the fourth end portion 180d and the fifth end portion 180e open to the outside of the busbar holder 175. The third holder flow path 183 is a flow path that linearly connects the fourth end portion 180d and the fifth end portion 180e. In this modified example, the third holder flow path 183 extends substantially parallel to the second holder flow path 82. That is, the third holder flow path 183 extends in one direction (+Z) as it moves toward the other side (-X) in the second direction. Furthermore, the third holder flow channel 183 may have a curved or bent portion between the fourth end 180d and the fifth end 180e, provided that it is connected to the fourth end 180d and the fifth end 180e. Also, the direction in which the third holder flow channel 183 extends is not limited to this modified example and does not necessarily have to be substantially parallel to the second holder flow channel 82.

[0097] The fourth end 180d opens on the upper surface 75f of the holder body 75g facing one side in the first direction (+Z). In this modified example, the fourth end 180d is positioned on the other side in the second direction (-X) of the second end 80b. Note that the position of the fourth end 180d is not limited to this modified example; for example, the fourth end 180d may be located on one side in the second direction (+X) of the second end 80b. The fourth end 180d is positioned on one side in the axial direction (+Y) of the guide portion 176, similar to the second end 80b. A portion of the fluid O that flows out from the second end 80b and is guided by the guide portion 176 to the other side in the second direction (-X) flows into the fourth end 180d. Therefore, the fourth end 180d functions as an inlet that guides the fluid O into the third holder flow path 183.

[0098] The fifth end portion 180e opens on the surface facing the other side (-Z) of the first direction of the holder body portion 75g. The fluid O in the third holder flow path portion 183 flows out from the fifth end portion 180e. Therefore, the fifth end portion 180e functions as an outlet for the fluid O in the third holder flow path portion 183. The fluid O flowing out from the fifth end portion 180e is supplied to another object to be cooled, such as the motor 2.

[0099] Figure 6 is a schematic cross-sectional view of the busbar unit 170, including the cross-sections of the second holder channel section 82 and the third holder channel section 183. As shown in Figure 6, the cross-sectional shape of the third holder channel section 183 in this modified example is rectangular, similar to the second holder channel section 82. However, the cross-sectional shape of the third holder channel section 183 may be other shapes, such as circular.

[0100] In this modified example, only a portion of the fluid O flowing out of the second holder flow path 82 flows into the third holder flow path 183. Therefore, the flow rate of the fluid O flowing through the third holder flow path 183 is less than the flow rate of the fluid O flowing through the second holder flow path 82. Consequently, the flow path cross-sectional area of ​​the third holder flow path 183 in this modified example is smaller than the flow path cross-sectional area of ​​the second holder flow path 82. However, the flow path cross-sectional area of ​​the third holder flow path 183 may be the same as the flow path cross-sectional area of ​​the second holder flow path 82, or it may be larger than the flow path cross-sectional area of ​​the second holder flow path 82.

[0101] In this modified example, the third holder flow channel 183 is located in the axial direction Y between the busbar body portion 71c of the first busbar 71 and the busbar body portion 72c of the second busbar 72. In this modified example, at least a portion of the busbar body portion 71c of the first busbar 71 is exposed to the internal space of the third holder flow channel 183. That is, at least a portion of the inner surface of the third holder flow channel 183 is made up of the first busbar 71. Also, similar to the embodiment described above, the second holder flow channel 82 is located between the busbar body portion 72c of the second busbar 72 and the busbar body portion 73c of the third busbar 73. At least a portion of the inner surface of the second holder flow channel 82 is made up of the second busbar 72.

[0102] In this modified configuration, the fluid O flowing through the third holder channel 183 directly contacts the first busbar 71. Similarly, the fluid O flowing through the second holder channel 82 directly contacts the second busbar 72. In this modified configuration, at least one of the multiple busbars 71, 72, and 73 (the first busbar 71 and the second busbar 72 in this configuration) is exposed to the internal space of the holder channel 180, allowing the busbar to be efficiently cooled by the fluid O. Note that the busbars 71, 72, and 73 do not necessarily have to constitute the inner surface of the holder channel 180. Even without direct contact with the busbars 71, 72, and 73, the fluid O receives heat from the busbars 71, 72, and 73 via the busbar holder 175, thereby cooling the busbars 71, 72, and 73.

[0103] In this modified example, the holder channel 180 has a third holder channel 183 in addition to the first holder channel 81 and the second holder channel 82. The third holder channel 183 has a fourth end 180d and a fifth end 180e. The fourth end 180d and the fifth end 180e open to the outside of the busbar holder 175. According to this modified example, the holder channel 180 having multiple channel sections makes it possible to cool a wide area of ​​the busbar unit 170.

[0104] In this modified example, the holder flow path 180 has multiple flow path sections (a second holder flow path section 82 and a third holder flow path section 183). At least one of the multiple flow path sections passes between adjacent busbars (a first busbar 71 and a second busbar 72, or a second busbar 72 and a third busbar 73). According to this modified example, adjacent busbars can be cooled by the second holder flow path section 82 and the third holder flow path section 183. In this modified example, the second holder flow path section 82 is located between the second busbar 72 and the third busbar 73, and the third holder flow path section 183 is located between the first busbar 71 and the second busbar 72. In this modified example, multiple busbars can be efficiently cooled because the multiple flow path sections (the second holder flow path section 82 and the third holder flow path section 183) are located between different busbars. Furthermore, the second holder flow channel 82 and the third holder flow channel 183 may both be located between two adjacent busbars (for example, between the first busbar 71 and the second busbar 72). In this case, the fluid O flowing through the second holder flow channel 82 and the third holder flow channel 183 can further cool these two busbars.

[0105] As shown in Figure 5, the busbar unit 170 of this modified example has a guide portion 176 that guides the fluid O flowing out from the second end 80b. According to this modified example, the fluid O flowing out from the second end can be guided to the object to be cooled, and a sufficient amount of fluid O can be supplied to the object to be cooled for cooling.

[0106] In this modified example, the guide portion 176 guides the fluid O flowing out from the second end portion 80b to the fourth end portion 180d. According to this modified example, the guide portion 176 can guide the fluid O that has flowed out of the busbar holder 175 to the third holder flow path portion 183.

[0107] In this modified example, the case where the guide portion 176 is part of the busbar holder 175 has been described. However, the guide portion 176 may also be part of any of the busbars 71, 72, or 73. Furthermore, in this modified example, the case where the guide portion 176 is a rib has been described. However, the guide portion 176 may also be a groove, for example, as long as it can guide the fluid O.

[0108] In this modified example, the arrangement of the second end 80b, the fourth end 180d, and the fifth end 180e on the surface of the busbar holder 175 is merely an example. The second end 80b, the fourth end 180d, and the fifth end 180e may be provided in positions different from those described in this modified example.

[0109] (Modification 2) Figure 7 is a front view of the busbar unit 270 of Modification 2. The busbar unit 270 of this modification differs from the embodiment described above mainly in the configuration of the holder flow path 280.

[0110] In this modified busbar unit 270, the motor 2 and the control unit 7 are electrically connected (see Figure 1). Similar to the embodiment described above, the busbar unit 270 in this modified version has a plurality of busbars 71, 72, 73 and a busbar holder 275. The busbar holder 275 is also provided with a holder flow path 280.

[0111] In this modified example, the holder channel 280 has a first holder channel section 81 and a second holder channel section 82, similar to those in the above-described embodiment, as well as a fourth holder channel section (fourth channel section) 284.

[0112] In this modified example, the fourth holder flow path 284 is provided on the holder body portion 75g of the busbar holder 275. The fourth holder flow path 284 branches off from the second holder internal branch portion 280h, which is provided in the path of the second holder flow path 82, and extends to the other side (-X) in the second direction. The fourth holder flow path 284 has a sixth end portion 280f that opens to the outside of the busbar holder 275. That is, the holder flow path 280 has a sixth end portion 280f. The sixth end portion 280f opens on the surface of the holder body portion 75g facing the other side (-X) in the second direction. The fourth holder flow path 284 extends from the second holder internal branch portion 280h to the other side (-X) in the second direction. The fourth holder flow path 284 is a flow path that linearly connects the second holder internal branch portion 280h and the sixth end portion 280f. Furthermore, the fourth holder flow channel 284 may have a curved or bent portion between the second holder internal branch 280h and the sixth end portion 280f, as long as it connects the second holder internal branch 280h and the sixth end portion 280f. Also, the direction in which the fourth holder flow channel 284 extends is not limited to this modified example. For example, the fourth holder flow channel 284 may extend from the second holder internal branch 280h in one side of the second direction (+X). Also, the arrangement of the sixth end portion 280f on the surface of the busbar holder 275 is not limited to this modified example. The sixth end portion 280f may, for example, open on the surface of the busbar holder 275 facing one side of the second direction (+X).

[0113] According to this modified example, the holder channel 280 has a fourth holder channel section 284 that further branches off from the second holder channel section 82, making it possible to cool a wide area of ​​the busbar unit 270. Furthermore, according to this modified example, the second holder channel section 82 has a second end 80b that opens to the outside, and the fourth holder channel section 284 has a sixth end 280f that opens to the outside. Therefore, the fluid O in the holder channel 280 can be supplied to multiple objects to be cooled.

[0114] 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.

[0115] For example, the configuration of each flow path section provided in the drive device is just one example and is not limited to the embodiments described above. Furthermore, the direction in which the fluid flows in each flow path section is not limited to the embodiments described above. For example, the flow direction of the fluid flowing through the first holder flow path section may be the other axial direction (-Y).

[0116] In the embodiments described above, a case in which the drive unit includes a power transmission unit has been 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 be meshed together. Also, in the embodiments and their modifications described above, a case in which the busbar unit includes multiple busbars has been described, but the busbar unit may include only one busbar.

[0117] 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 busbar unit having a busbar connected to the motor and a busbar holder that supports the busbar, The motor and the housing that accommodates the busbar unit are provided. The housing is provided with a first housing channel through which fluid can flow, The busbar holder is provided with a holder channel, The holder flow path is, A first end connected directly or indirectly to the first housing flow path, The busbar holder has a second end that opens to the outside, Drive unit. (2) The housing is provided with a second housing flow path, The holder flow path is, A first flow channel section having a first end and a third end directly or indirectly connected to the second housing flow channel, and connecting the first housing flow channel and the second housing flow channel, It has a second flow channel branching off from the first flow channel, The drive device according to (1), wherein the second flow channel portion has the second end portion. (3) The busbar unit has a plurality of busbars, The drive device according to (1) or (2), wherein at least a portion of the holder flow path passes between one of the multiple busbars and another busbar. (4) The busbar unit has a plurality of busbars, The holder flow path has a plurality of flow path sections, The drive device according to (3), wherein at least one of the plurality of flow channels passes between adjacent busbars. (5) The drive device according to any one of (1) to (4), wherein the busbar unit has a guide portion for guiding the fluid flowing out from the second end. (6) The holder flow path has a third flow path section, The third flow channel portion has a fourth end and a fifth end, The drive device according to (2), wherein the fourth and fifth ends open to the outside of the busbar holder. (7) The drive device according to (6), wherein the busbar unit has a guide portion for guiding the fluid flowing out from the second end to the fourth end. (8) The holder flow path is The second flow channel section, It has a fourth channel section that branches off from the second channel section, The second flow channel section has the second end, The drive device according to (1), wherein the fourth flow channel has a sixth end that opens to the outside of the busbar holder. (9) At least a portion of the bus bar is located inside the bus bar holder, The drive device according to any one of (1) to (8), wherein at least a portion of the inner surface of the holder flow path is formed by the bus bar. [Explanation of Symbols]

[0118] 2...Motor, 6...Housing, 20...Rotor, 25...Stator, 70, 170, 270...Busbar unit, 71, 72, 73...Busbar, 75, 175, 275...Busbar holder, 80, 180, 280...Holder flow path, 80a...First end, 80b...Second end, 80c...Third end, 81...First holder flow path section (First flow path section), 82, 82A...Second holder flow path section (Second 2 flow channels), 92...Second housing flow channel (first housing flow channel), 94...Fourth housing flow channel (second housing flow channel), 100...Drive unit, 176...Guide section, 180d...Fourth end, 180e...Fifth end, 183...Third holder flow channel (third flow channel), 280f...Sixth end, 284...Fourth holder flow channel (fourth flow channel), J1...First axis (center axis), O...Fluid

Claims

1. A motor having a rotor that can rotate about a central axis, and a stator facing the rotor, A busbar unit having a busbar connected to the motor and a busbar holder that supports the busbar, The motor and the housing that accommodates the busbar unit are provided. The housing is provided with a first housing channel through which fluid can flow, The busbar holder is provided with a holder channel, The holder flow path is A first end connected directly or indirectly to the first housing flow path, The busbar holder has a second end that opens to the outside, Drive unit.

2. The housing is provided with a second housing flow path, The holder flow path is A first flow channel section having a third end directly or indirectly connected to the first end and the second housing flow channel, and connecting the first housing flow channel and the second housing flow channel, It has a second flow channel branching off from the first flow channel, The second flow channel portion has the second end portion, The drive device according to claim 1.

3. The busbar unit has a plurality of busbars, At least a portion of the holder flow path passes between one of the multiple busbars and another busbar. The drive device according to claim 1 or 2.

4. The busbar unit has a plurality of busbars, The holder flow path has a plurality of flow path sections, At least one of the plurality of flow channels passes between adjacent busbars, The drive device according to claim 3.

5. The busbar unit has a guide portion for guiding the fluid flowing out from the second end. The drive device according to claim 1.

6. The holder flow path has a third flow path section, The third flow channel section has a fourth end and a fifth end, The fourth and fifth ends open to the outside of the busbar holder. The drive device according to claim 2.

7. The busbar unit has a guide portion that guides the fluid flowing out from the second end to the fourth end. The drive device according to claim 6.

8. The holder flow path is The second flow channel section, It has a fourth channel section that branches off from the second channel section, The second flow channel portion has the second end portion, The fourth flow channel has a sixth end that opens to the outside of the busbar holder. The drive device according to claim 1.

9. At least a portion of the bus bar is located inside the bus bar holder, At least a portion of the inner surface of the holder flow path is formed by the bus bar. The drive device according to claim 1.

Images