JP7424106B2 - drive device - Google Patents

Description

The present invention relates to a drive device.

2. Description of the Related Art A drive device is known that includes two housings and a partition wall that separates the interiors of the two housings, and in which the partition wall is provided with a through hole that connects the interiors of the two housings. For example, Patent Document 1 describes a power transmission device for a vehicle as such a drive device.

Japanese Patent Application Publication No. 2013-119918

In the above drive device, fluid such as oil accumulated inside one housing may flow into the inside of the other housing through a through hole provided in the partition wall. However, simply providing a through hole may make it difficult for fluid such as oil to flow into the other housing.

In view of the above circumstances, one object of the present invention is to provide a drive device having a structure that allows fluid such as oil to easily flow from the inside of one housing to the inside of the other housing.

One aspect of the drive device of the present invention includes a motor and a housing that houses the motor therein. The housing includes a first housing, a second housing connected to the first housing, and a partition wall separating the inside of the first housing and the inside of the second housing. The first housing has a first bottom portion located on one side in a predetermined direction. The second housing has a second bottom portion located on one side in the predetermined direction. At least a portion of the second bottom surface on the other side in the predetermined direction is located closer to one side in the predetermined direction than the first bottom surface on the other side in the predetermined direction. The first bottom portion has a concave portion recessed toward one side in the predetermined direction at a position adjacent to the partition wall. The partition wall has a through hole that connects the inside of the first housing and the inside of the second housing. The inside of the recess is connected to the inside of the through hole.

According to one aspect of the present invention, in the drive device, fluid such as oil can easily flow from the inside of one housing to the inside of the other housing.

FIG. 1 is a schematic configuration diagram schematically showing a drive device according to a first embodiment. FIG. 2 is a sectional view showing a through hole and a recess in the first embodiment. FIG. 3 is a perspective view showing a through hole and a recess in the first embodiment. FIG. 4 is an axial view of the through hole and recess of the first embodiment. FIG. 5 is a cross-sectional view showing a through hole and a recess in a modification of the first embodiment. FIG. 6 is a sectional view showing a through hole and a recess in the second embodiment.

In the following description, the vertical direction will be defined based on the positional relationship when the drive device of each embodiment shown in each figure is mounted on a vehicle located on a horizontal road surface. In addition, in the drawings, an XYZ coordinate system is appropriately shown as a three-dimensional orthogonal coordinate system. In the XYZ coordinate system, the Z-axis direction is the vertical direction. The +Z side is the upper side in the vertical direction, and the -Z side is the lower side in the vertical direction. In the following description, the upper side in the vertical direction is simply referred to as the "upper side", and the lower side in the vertical direction is simply referred to as the "lower side". The X-axis direction is a direction perpendicular to the Z-axis direction, and is the front-rear direction of the vehicle in which the drive device is mounted. In each embodiment below, the +X side is the front side of the vehicle, and the -X side is the rear side of the vehicle. The Y-axis direction is a direction perpendicular to both the X-axis direction and the Z-axis direction, and is the left-right direction of the vehicle, that is, the vehicle width direction. In each embodiment below, the +Y side is the left side of the vehicle, and the -Y side is the right side of the vehicle. The front-rear direction and the left-right direction are horizontal directions perpendicular to the vertical direction. In each embodiment, the vertical direction corresponds to a "predetermined direction". The lower side corresponds to "one side in the predetermined direction" and the upper side corresponds to "the other side in the predetermined direction."

Note that the positional relationship in the longitudinal direction is not limited to the positional relationship in each embodiment below, and the +X side may be the rear side of the vehicle and the -X side may be the front side of the vehicle. In this case, the +Y side is the right side of the vehicle and the -Y side is the left side of the vehicle.

A motor shaft J1 shown as appropriate in each figure extends in a direction intersecting the vertical direction. More specifically, the motor shaft J1 extends in the Y-axis direction, that is, in the left-right direction of the vehicle. In the following description, unless otherwise specified, the direction parallel to the motor shaft J1 is simply referred to as the "axial direction", the radial direction centered on the motor shaft J1 is simply referred to as the "radial direction", and the direction parallel to the motor shaft J1 is simply referred to as the "radial direction". The circumferential direction around the center, that is, the circumferential direction around the motor shaft J1 is simply referred to as the "circumferential direction." Note that in this specification, "parallel directions" include substantially parallel directions, and "orthogonal directions" include substantially orthogonal directions.

<First embodiment>
A drive device 1 according to the present embodiment shown in FIG. 1 is installed in a vehicle that uses a motor as a power source, such as a hybrid vehicle (HEV), a plug-in hybrid vehicle (PHV), or an electric vehicle (EV), and is used as the power source. be done. As shown in FIG. 1, the drive device 1 includes a motor 2, a transmission device 3 including a speed reduction device 4 and a differential device 5, a housing 6, an oil pump 96, a cooler 97, and a pipe 10. . Note that in this embodiment, the drive device 1 does not include an inverter unit. In other words, the drive device 1 has a separate structure from the inverter unit.

The housing 6 houses the motor 2 and the transmission device 3 therein. The housing 6 includes a first housing 61, a second housing 62, and a partition wall 63. The first housing 61 houses the motor 2 therein. The second housing 62 accommodates the transmission device 3 therein. The second housing 62 is connected to the first housing 61. In this embodiment, the second housing 62 is located on the left side of the first housing 61. The partition wall 63 separates the inside of the first housing 61 and the inside of the second housing 62. The partition wall 63 has a through hole 68 that connects the inside of the first housing 61 and the inside of the second housing 62.

The first housing 61 surrounds the motor 2 from the outside in the radial direction. As shown in FIG. 2, the inner peripheral surface of the first housing 61 is a tapered surface whose inner diameter increases toward the right side. The first housing 61 has a first bottom portion 61a located on the lower side. The bottom surface 61b of the first bottom portion 61a is a part of the inner peripheral surface of the first housing 61. Since the inner circumferential surface of the first housing 61 is a tapered surface, the bottom surface 61b is an inclined surface that is located lower toward the right side. The bottom surface 61b is the upper surface of the first bottom portion 61a.

As shown in FIGS. 2 to 4, the first bottom portion 61a has a recessed portion 64 that is recessed downward at a position adjacent to the partition wall 63. As shown in FIGS. As shown in FIG. 4, the recess 64 is, for example, depressed diagonally downward and forward from the bottom surface 61b. The inside of the recess 64 has a substantially rectangular shape when viewed in the axial direction. As shown in FIG. 3, in this embodiment, the recess 64 is a groove extending in the axial direction. The right end of the recess 64 is closed. The left end of the recess 64 is connected to the through hole 68 . Thereby, the inside of the recess 64 is connected to the inside of the through hole 68. Thus, in this embodiment, the recess 64 is a groove that extends to the through hole 68. A left end of the recess 64 opens into the second housing 62 through a through hole 68 .

As shown in FIG. 2, the lower surface of the inner surface of the recess 64 is an inclined surface 64a that is located lower toward the through hole 68. In this embodiment, the inclined surface 64a is located on the left side. It is located slightly lower as you go towards it. A surface located on the right side of the inner surface of the recess 64 is a connecting surface 64b that extends downward from the bottom surface 61b of the first bottom portion 61a and connects the bottom surface 61b and the inclined surface 64a. The connection surface 64b is, for example, a flat surface perpendicular to the axial direction. The connecting surface 64b is a stepped surface provided between the bottom surface 61b and the inclined surface 64a.

In this specification, "the recess is recessed toward one side in a predetermined direction" may mean that the direction in which the recess is recessed includes a component toward one side in the predetermined direction. For example, in the present embodiment, "the recessed portion 64 is recessed downward" may mean that the recessed direction of the recessed portion 64 includes a downward component. That is, in the present embodiment, "the recess 64 is depressed downward" means that the recess 64 may be depressed directly below in the vertical direction, or in a direction perpendicular to the vertical direction within a range of less than 90 degrees with respect to directly below the vertical direction. It may be recessed in a diagonal direction. As described above, in the illustrated example, the recess 64 is recessed downward and obliquely forward.

The second housing 62 has a second bottom portion 62a located on the lower side. At least a portion of the bottom surface 62b of the second bottom portion 62a is located below the bottom surface 61b of the first bottom portion 61a. In this embodiment, the entire bottom surface 62b of the second bottom portion 62a is located below the bottom surface 61b of the first bottom portion 61a. The bottom surface 62b is the upper surface of the second bottom portion 62a. For example, the bottom surface 62b is located further away below the through hole 68. A step is provided between the bottom surface 62b and the inclined surface 64a of the recess 64. In this embodiment, the entire second bottom portion 62a is located below the first bottom portion 61a.

As shown in FIG. 1, in this embodiment, the partition wall 63 partitions the inside of the first housing 61 and the inside of the second housing 62 in the axial direction. The partition wall 63 is located on the left side of the stator 30. The partition wall 63 holds a bearing 27, which will be described later. As shown in FIG. 2, the portion of the partition wall 63 where the bearing 27 is held projects, for example, to the left. The portion of the partition wall 63 where the bearing 27 is held is, for example, the center portion of the partition wall 63 in the vertical direction.

In this embodiment, the through hole 68 is provided at the lower end of the partition wall 63. The through hole 68 passes through the lower end of the partition wall 63, for example, in an axially diagonal downward direction from a surface on the first housing 61 side toward a surface on the second housing 62 side. As a result, the opening 68c of the through hole 68 that opens into the inside of the first housing 61 opens obliquely upward in the vertical direction. The opening 68d of the through hole 68 that opens into the second housing 62 opens in a direction that is obliquely inclined downward in the vertical direction.

The lower end of the through hole 68 is located below the bottom surface 61b. In this embodiment, the lower end of the through hole 68 is located at the same position as the lower end of the recess 64 in the vertical direction. As a result, the lower end of the recess 64 opens into the second housing 62 through the through hole 68 . In this embodiment, the upper end of the through hole 68 is located above the first bottom 61a.

In this embodiment, the entire left (+Y side) end of the recess 64 is connected to the through hole 68 and opens into the second housing 62 via the through hole 68 . As shown in FIG. 4, the entire recess 64 overlaps with the through hole 68 when viewed in the axial direction in which the first housing 61 and the second housing 62 are lined up.

The through hole 68 has an upper portion 68a and a lower portion 68b. The upper portion 68a is a portion of the through hole 68 located above the bottom surface 61b. The upper portion 68a connects the inside of the first housing 61 and the inside of the second housing 62 without using the recess 64. The lower portion 68b is connected to the lower side of the upper portion 68a. The lower portion 68b is formed by the opening of the recess 64 on the second housing 62 side. The lower portion 68b connects the inside of the first housing 61 and the inside of the second housing 62 via the recess 64. The longitudinal dimension of the lower portion 68b is smaller than the longitudinal dimension of the upper portion 68a.

In this embodiment, the partition wall 63, the portion of the first housing 61 that circumferentially surrounds the motor 2, and the portion of the second housing 62 that circumferentially surrounds the transmission device 3 are integrally formed bodies. be. The molded body is made, for example, by die casting. For example, after molding the molded body, the mold for molding the through hole 68 and the recess 64 is moved to the left side and removed from the molded body. Here, as described above, the inclined surface 64a of the recess 64 is an inclined surface located slightly lower toward the left. In this way, the inclined surface 64a of the recess 64 is provided with a draft angle, so that the portion of the mold for molding the recess 64 can be easily pulled out to the left.

As shown in FIG. 1, the housing 6 accommodates oil O as a refrigerant therein. In this embodiment, oil O is accommodated inside the first housing 61 and the second housing 62. An oil reservoir P in which oil O accumulates is provided in a lower region inside the second housing 62 . Oil O in the oil reservoir P is sent into the first housing 61 through an oil passage 90, which will be described later. The oil O sent into the first housing 61 accumulates in a lower region inside the first housing 61 . At least a portion of the oil O accumulated inside the first housing 61 moves to the second housing 62 via the through hole 68 and returns to the oil reservoir P.

In addition, in this specification, "oil is stored inside a certain part" means that oil is located inside a certain part at least part of the time the motor is being driven; When the engine is stopped, there is no need for oil to be located inside a certain part. For example, in this embodiment, the oil O is stored inside the first housing 61, which means that the oil O is located inside the first housing 61 at least partially while the motor 2 is being driven. Alternatively, when the motor 2 is stopped, all the oil O inside the first housing 61 may have moved to the second housing 62 through the through hole 68. Note that a part of the oil O sent into the first housing 61 through an oil passage 90, which will be described later, may remain inside the first housing 61 when the motor 2 is stopped.

Oil O circulates within an oil passage 90, which will be described later. Oil O is used for lubricating the reduction gear 4 and the differential gear 5. Further, oil O is used for cooling the motor 2. As the oil O, in order to perform the functions of a lubricating oil and a cooling oil, it is preferable to use an oil equivalent to automatic transmission fluid (ATF), which has a relatively low viscosity.

In this embodiment, the motor 2 is an inner rotor type motor. The motor 2 includes a rotor 20, a stator 30, and bearings 26 and 27. The rotor 20 is rotatable around a motor shaft J1 that extends in the horizontal direction. The rotor 20 has a shaft 21 and a rotor body 24. Although not shown, the rotor main body 24 includes a rotor core and a rotor magnet fixed to the rotor core. The torque of the rotor 20 is transmitted to the transmission device 3.

The shaft 21 extends in the axial direction centering on the motor shaft J1. The shaft 21 rotates around the motor shaft J1. The shaft 21 is a hollow shaft with a hollow portion 22 provided therein. The shaft 21 is provided with a communication hole 23 . The communication hole 23 extends in the radial direction and connects the hollow portion 22 and the outside of the shaft 21.

The shaft 21 extends across the first housing 61 and the second housing 62 of the housing 6. The left end of the shaft 21 projects into the second housing 62 . A first gear 41 of the transmission device 3, which will be described later, is fixed to the left end of the shaft 21. The shaft 21 is rotatably supported by bearings 26 and 27.

The stator 30 faces the rotor 20 in the radial direction with a gap therebetween. More specifically, stator 30 is located radially outside of rotor 20. Stator 30 includes a stator core 32 and a coil assembly 33. Stator core 32 surrounds rotor 20 . Stator core 32 is fixed to the inner circumferential surface of first housing 61 . Although not shown, the stator core 32 includes a cylindrical core back that extends in the axial direction, and a plurality of teeth that extend inward in the radial direction from the core back. The plurality of teeth are arranged at equal intervals all around the circumferential direction.

As shown in FIG. 2, a gap G is provided between the stator core 32 and the first bottom portion 61a in the vertical direction. In the present embodiment, the bottom surface 61b of the first bottom portion 61a is positioned upward toward the left, so the vertical dimension of the gap G becomes smaller toward the left.

As shown in FIG. 1, the coil assembly 33 includes a plurality of coils 31 attached to the stator core 32 along the circumferential direction. The plurality of coils 31 are respectively attached to each tooth of the stator core 32 via an insulator (not shown). The plurality of coils 31 are arranged along the circumferential direction. More specifically, the plurality of coils 31 are arranged at regular intervals along the circumferential direction. Although not shown in the drawings, the coil assembly 33 may have a binding member that binds the coils 31 together, or may have a crossover wire that connects the coils 31 together.

Coil assembly 33 has coil ends 33a and 33b that protrude from stator core 32 in the axial direction. The coil end 33a is a portion that projects from the stator core 32 to the right side. Coil end 33b is a portion that protrudes from stator core 32 to the left side. Coil end 33a includes a portion of each coil 31 included in coil assembly 33 that protrudes to the right side of stator core 32. Coil end 33b includes a portion of each coil 31 included in coil assembly 33 that protrudes to the left of stator core 32. As shown in FIG. 2, in this embodiment, the coil ends 33a and 33b have an annular shape centered on the motor shaft J1. Although not shown, the coil ends 33a and 33b may include a binding member for binding each coil 31, or may include a crossover wire for connecting each coil 31.

As shown in FIG. 1, bearings 26 and 27 rotatably support rotor 20. As shown in FIG. The bearings 26 and 27 are, for example, ball bearings. The bearing 26 is a bearing that rotatably supports a portion of the rotor 20 located on the right side of the stator core 32. In this embodiment, the bearing 26 supports a portion of the shaft 21 located on the right side of the portion to which the rotor body 24 is fixed. The bearing 26 is held by a wall portion 61c of the first housing 61 that covers the right side of the rotor 20 and the stator 30.

The bearing 27 is a bearing that rotatably supports a portion of the rotor 20 located on the left side of the stator core 32. In this embodiment, the bearing 27 supports a portion of the shaft 21 located on the left side of the portion to which the rotor body 24 is fixed. The bearing 27 is held by the partition wall 63.

The transmission device 3 is housed in a second housing 62 of the housing 6. The transmission device 3 is connected to the motor 2. More specifically, the transmission device 3 is connected to the left-hand end of the shaft 21. The transmission device 3 includes a speed reduction device 4 and a differential device 5. Torque output from the motor 2 is transmitted to the differential gear 5 via the reduction gear 4.

The speed reducer 4 is connected to the motor 2 . The speed reducer 4 reduces the rotational speed of the motor 2 and increases the torque output from the motor 2 according to the speed reduction ratio. The reduction gear 4 transmits the torque output from the motor 2 to the differential gear 5. The speed reduction device 4 includes a first gear 41, a second gear 42, a third gear 43, and an intermediate shaft 45.

The first gear 41 is fixed to the outer peripheral surface of the left end of the shaft 21. The first gear 41 rotates together with the shaft 21 around the motor shaft J1. Intermediate shaft 45 extends along intermediate axis J2 parallel to motor axis J1. The intermediate shaft 45 rotates around the intermediate shaft J2. The second gear 42 and the third gear 43 are fixed to the outer peripheral surface of the intermediate shaft 45. The second gear 42 and the third gear 43 are connected via an intermediate shaft 45. The second gear 42 and the third gear 43 rotate around the intermediate shaft J2. The second gear 42 meshes with the first gear 41. The third gear 43 meshes with a ring gear 51, which will be described later, of the differential device 5.

Torque output from the motor 2 is transmitted to the ring gear 51 of the differential device 5 via the shaft 21, the first gear 41, the second gear 42, the intermediate shaft 45, and the third gear 43 in this order. The gear ratio of each gear, the number of gears, etc. can be changed in various ways depending on the required reduction ratio. In this embodiment, the speed reducer 4 is a parallel shaft gear type speed reducer in which the axes of each gear are arranged in parallel.

The differential gear 5 is connected to the motor 2 via the speed reduction gear 4 . The differential device 5 is a device for transmitting torque output from the motor 2 to the wheels of the vehicle. The differential device 5 absorbs the speed difference between the left and right wheels when the vehicle turns, and transmits the same torque to the axles 55 of both the left and right wheels. Thus, in this embodiment, the transmission device 3 transmits the torque of the motor 2 to the axle 55 of the vehicle via the reduction gear device 4 and the differential device 5. The differential device 5 includes a ring gear 51, a gear housing (not shown), a pair of pinion gears (not shown), a pinion shaft (not shown), and a pair of side gears (not shown). The ring gear 51 rotates around a differential shaft J3 parallel to the motor shaft J1. Torque output from the motor 2 is transmitted to the ring gear 51 via the reduction gear device 4 .

The motor 2 is provided with an oil passage 90 through which oil O circulates inside the housing 6. The oil passage 90 is an oil O path that supplies oil O from the oil reservoir P to the motor 2 and leads it back to the oil reservoir P. The oil passage 90 is provided across the inside of the first housing 61 and the inside of the second housing 62.

Note that in this specification, "oil path" means an oil path. Therefore, the term "oil path" is a concept that includes not only a "flow path" that creates a constant flow of oil in one direction, but also a path where oil temporarily remains and a path where oil drips. The path for temporarily retaining oil includes, for example, a reservoir for storing oil.

The oil passage 90 has a first oil passage 91 and a second oil passage 92. The first oil passage 91 and the second oil passage 92 each circulate oil O inside the housing 6. The first oil passage 91 has a scooping passage 91a, a shaft supply passage 91b, an intra-shaft passage 91c, and an intra-rotor passage 91d. Further, a first reservoir 93 is provided in the path of the first oil passage 91 . The first reservoir 93 is provided within the second housing 62 .

The scraping path 91 a is a path that scrapes up oil O from the oil reservoir P by rotation of the ring gear 51 of the differential device 5 and receives the oil O in the first reservoir 93 . The first reservoir 93 opens upward. The first reservoir 93 receives the oil O stirred up by the ring gear 51. Further, when the liquid level Sg of the oil reservoir P is high, such as immediately after the motor 2 is driven, the first reservoir 93 is scraped up by the second gear 42 and the third gear 43 in addition to the ring gear 51. It also receives oil O.

The shaft supply path 91b guides the oil O from the first reservoir 93 to the hollow portion 22 of the shaft 21. The intra-shaft path 91c is a path through which the oil O passes through the hollow portion 22 of the shaft 21. The internal rotor path 91d is a path that passes from the communication hole 23 of the shaft 21 through the inside of the rotor body 24, and is scattered to the stator 30.

The internal rotor path 91d has a supply port 24a provided in the rotor body 24. The supply port 24a opens inside the first housing 61. Oil O passing through the rotor internal path 91d is injected toward the stator 30 from the supply port 24a. In this way, the supply port 24a supplies the oil O as a fluid into the first housing 61. For example, a plurality of supply ports 24a are provided. In this embodiment, the rotor main body 24 corresponds to a supply section having a supply port 24a.

In the shaft inner path 91c, centrifugal force is applied to the oil O inside the rotor 20 as the rotor 20 rotates. As a result, the oil O is continuously scattered radially outward from the rotor 20. Further, as the oil O scatters, the path inside the rotor 20 becomes negative pressure, the oil O accumulated in the first reservoir 93 is sucked into the rotor 20, and the path inside the rotor 20 is filled with oil O.

The oil O that has reached the stator 30 removes heat from the stator 30. The oil O that has cooled the stator 30 is dripped downward and accumulates in the lower region within the first housing 61 . Oil O accumulated in the lower region within the first housing 61 moves to the second housing 62 via a through hole 68 provided in the partition wall 63. As described above, the first oil passage 91 supplies oil O to the rotor 20 and the stator 30.

In the second oil passage 92, oil O is pulled up from the oil reservoir P and supplied to the stator 30. The second oil passage 92 is provided with an oil pump 96, a cooler 97, and a pipe 10. The second oil passage 92 has a first passage 92a, a second passage 92b, a third passage 92c, and a fourth passage 94.

The first flow path 92a, the second flow path 92b, the third flow path 92c, and the fourth flow path 94 are provided in the wall of the housing 6. The first flow path 92a connects the oil reservoir P and the oil pump 96. The second flow path 92b connects the oil pump 96 and the cooler 97. The third flow path 92c connects the cooler 97 and the fourth flow path 94. The third flow path 92c is provided, for example, in the front (+X side) wall of the first housing 61. The fourth flow path 94 is provided in the partition wall 63. The fourth flow path 94 connects the third flow path 92c and the pipe 10.

In this embodiment, the pipe 10 extends in the axial direction. The left end of the pipe 10 is fixed to the partition wall 63. In this embodiment, the pipe 10 has a cylindrical shape that extends linearly in the axial direction. The pipe 10 is housed inside the housing 6. The pipe 10 is located on the radially outer side of the stator 30. The pipe 10 is located above the stator 30, for example. Note that a plurality of pipes 10 may be provided.

The pipe 10 has supply ports 11 and 12 that supply oil O as a fluid into the first housing 61 . The supply ports 11 and 12 open into the first housing 61 . Oil O flowing into the pipe 10 from the fourth flow path 94 is injected toward the stator 30 from the supply ports 11 and 12. Oil O injected from the supply port 11 is supplied to the stator core 32. Oil O injected from the supply port 12 is supplied to the coil ends 33a and 33b. For example, a plurality of supply ports 11 and a plurality of supply ports 12 are provided. In this embodiment, the pipe 10 corresponds to a supply section having supply ports 11 and 12.

As described above, in this embodiment, the drive device 1 includes the rotor main body 24 and the pipe 10 as a supply section. In this embodiment, the opening area of the opening 68c and the opening area of the opening 68d of the through hole 68 are each larger than the total opening area of the supply ports 11, 12, and 24a. In this embodiment, the total opening area of the supply ports 11, 12, and 24a is the sum total of the opening areas of all the supply ports 11, 12, and 24a. Note that, for example, when only one supply port is provided, the total opening area of the supply ports is the opening area of one supply port.

The oil pump 96 is a pump that sends oil O as a refrigerant. In this embodiment, the oil pump 96 is an electric pump driven by electricity. The oil pump 96 sucks up oil O from the oil reservoir P through the first flow path 92a, and supplies the oil O to the second flow path 92b, the cooler 97, the third flow path 92c, the fourth flow path 94, and the pipe. Oil O is supplied to the motor 2 via 10.

The oil O supplied from the pipe 10 to the stator 30 drips downward and accumulates in a lower region within the first housing 61 . The oil O accumulated in the lower region within the first housing 61 moves to the oil reservoir P of the second housing 62 via the through hole 68 provided in the partition wall 63. As described above, the second oil passage 92 supplies oil O to the stator 30.

The cooler 97 cools the oil O passing through the second oil passage 92. A second flow path 92b and a third flow path 92c are connected to the cooler 97. The cooler 97 has a flow path 97a that connects a second flow path 92b and a third flow path 92c. The flow path 97a is a flow path provided inside the cooler 97. The flow path 97a is connected to the inside of the second housing 62 via the second flow path 92b and the first flow path 92a. The cooler 97 is connected to a cooling water pipe 98 through which cooling water cooled by a radiator (not shown) passes. The oil O passing through the flow path 97a provided inside the cooler 97 is cooled by heat exchange with the cooling water passing through the cooling water pipe 98.

As shown in FIG. 2, the cooler 97 is fixed to the outer surface of the first housing 61. More specifically, the cooler 97 is fixed to the outer surface of the portion of the first bottom 61a where the recess 64 is provided. At least a portion of the cooler 97 overlaps with the recess 64 when viewed in the direction in which the recess 64 is depressed. In this embodiment, the left end of the cooler 97 overlaps the recess 64 when viewed in the direction in which the recess 64 is depressed. In this embodiment, the cooler 97 corresponds to an auxiliary machine.

The drive device 1 further includes a temperature sensor 70 that can detect the temperature of the motor 2. The type of temperature sensor 70 is not particularly limited as long as it can detect the temperature of the motor 2. The temperature of the motor 2 includes the temperature of the stator 30. In this embodiment, the temperature sensor 70 is capable of detecting the temperature of the stator 30. Temperature sensor 70 is located inside first housing 61 . In this embodiment, the temperature sensor 70 is arranged at the coil end 33b. More specifically, at least a portion of the temperature sensor 70 is embedded in the coil end 33b. In this embodiment, the temperature sensor 70 is inserted into the coil end 33b and is almost entirely embedded in the coil end 33b.

In this embodiment, the temperature sensor 70 is arranged at the vertical center of the coil end 33b. For example, the temperature sensor 70 overlaps the shaft 21 when viewed in the front-rear direction. The temperature sensor 70 is located above the through hole 68. Here, in this embodiment, the oil O accumulated in the first housing 61 flows to the second housing 62 through the through hole 68, so that the liquid level Sm of the oil O in the first housing 61 is lower than that of the through hole 68. Also, it is difficult to be on the upper side. Thereby, by arranging the temperature sensor 70 above the through hole 68, the temperature sensor 70 can be prevented from being soaked in the oil O inside the first housing 61.

When temperature sensor 70 is immersed in oil O, the temperature detected by temperature sensor 70 decreases regardless of the actual temperature of stator 30. Therefore, it may become difficult to accurately detect the temperature of the stator 30. On the other hand, according to the present embodiment, since the temperature sensor 70 is not easily immersed in the oil O as described above, it is possible to suppress the difficulty in accurately detecting the temperature of the stator 30 by the temperature sensor 70.

In this embodiment, the drive device 1 controls the drive of the oil pump 96 based on the detection result of the temperature sensor 70. For example, when the drive device 1 determines that the temperature of the stator 30 is equal to or higher than a predetermined threshold based on the detection result of the temperature sensor 70, the drive device 1 increases the output of the oil pump 96. Thereby, the amount of oil O supplied to the stator 30 via the first oil passage 91 and the second oil passage 92 can be increased, and the temperature of the stator 30 can be lowered.

According to this embodiment, the first bottom portion 61a has a recessed portion 64 that is recessed downward at a position adjacent to the partition wall 63. The partition wall 63 has a through hole 68 that connects the inside of the first housing 61 and the inside of the second housing 62. The inside of the recess 64 is connected to the inside of the through hole 68. Therefore, the through hole 68 can be enlarged in the direction in which the recess 64 is depressed. Thereby, the overall size of the through hole 68 can be increased without expanding the through hole 68 upward. Therefore, for example, the through hole 68 can be made larger while avoiding interference with the bearing 27 etc. held by the partition wall 63. Therefore, the oil O can easily flow from the inside of the first housing 61 to the inside of the second housing 62 through the through hole 68.

Further, by providing the recess 64, it is possible to widen the gap between the member housed inside the first housing 61 and the first bottom portion 61a. In this embodiment, the recess 64 can widen the gap between the motor 2 and the first bottom 61a. Therefore, the oil O in the first housing 61 can be easily guided to the through hole 68 via the recess 64. Thereby, the oil O can easily flow from the inside of the first housing 61 to the inside of the second housing 62 via the through hole 68.

In particular, when the bottom surface 61b of the first bottom portion 61a is an inclined surface that approaches the motor 2 as it goes toward the partition wall 63 as in this embodiment, the gap G between the bottom surface 61b and the stator 30 in the axial direction is It becomes narrower toward the partition wall 63. Therefore, there is a possibility that the oil O in the first housing 61 becomes difficult to flow into the through hole 68. On the other hand, by providing the recessed portion 64, the space between the stator 30 and the first bottom portion 61a is reduced in the portion of the first bottom portion 61a adjacent to the partition wall 63, that is, the portion where the gap G with the stator 30 is the narrowest. Can be expanded. As a result, even if the bottom surface 61b is an inclined surface that approaches the motor 2 as it goes toward the partition wall 63, the oil O inside the first housing 61 can be transferred to the inside of the second housing 62 through the through hole 68. It can be easily washed away.

As described above, by making it easier for the oil O to flow from the inside of the first housing 61 to the inside of the second housing 62, it is possible to suppress the oil O from accumulating too much inside the first housing 61. Therefore, for example, the liquid level Sm of the oil O in the first housing 61 can be prevented from being located above the lower end of the rotor 20. Thereby, when the rotor 20 rotates, it is possible to suppress the oil O accommodated inside the first housing 61 from becoming a resistance. Further, it is possible to further suppress the temperature sensor 70 from being immersed in the oil O.

Further, according to the present embodiment, the predetermined direction is the vertical direction, and one side in the predetermined direction where the recess 64 is depressed is the lower side in the vertical direction. Therefore, the oil O in the first housing 61 can easily flow from the recess 64 to the through hole 68 by gravity. This allows the oil O to flow more easily from the inside of the first housing 61 to the inside of the second housing 62.

Further, according to the present embodiment, the entire upper surface of the second bottom portion 62a, that is, the bottom surface 62b, is located below the upper surface of the first bottom portion 61a, that is, the bottom surface 61b. Therefore, as shown in FIG. 2, the oil O accumulated on the first bottom part 61a in the first housing 61 is caused to flow from the through hole 68 onto the second bottom part 62a in the second housing 62 using gravity. It's easy to do. This allows the oil O to flow more easily from the inside of the first housing 61 to the inside of the second housing 62.

Further, according to the present embodiment, the opening 68d of the through hole 68 that opens into the inside of the second housing 62 opens in a direction that is obliquely inclined downward in the vertical direction. Therefore, the oil O flowing into the second housing 62 from the through hole 68 can easily flow using gravity. This allows the oil O to flow more easily from the inside of the first housing 61 to the inside of the second housing 62.

Further, according to the present embodiment, the upper end of the through hole 68 is located above the first bottom portion 61a. Therefore, the through hole 68 can be made larger. This allows the oil O to flow more easily from the inside of the first housing 61 to the inside of the second housing 62.

Further, according to the present embodiment, the lower end of the recess 64 opens into the second housing 62 through the through hole 68 . Therefore, the through hole 68 can be made larger than when the lower end of the recess 64 is closed by the partition wall 63. This makes it easy to make the through hole 68 larger by making maximum use of the depressed recess 64. Therefore, the oil O can flow more easily from the inside of the first housing 61 to the inside of the second housing 62.

Further, according to this embodiment, the recess 64 is a groove extending to the through hole 68. Therefore, the oil O that has flowed into the recess 64 in the first housing 61 can be more easily guided to the through hole 68. This allows the oil O to flow more easily from the inside of the first housing 61 to the inside of the second housing 62.

Further, according to the present embodiment, the lower surface of the inner surface of the recess 64 is the inclined surface 64 a that is lower toward the through hole 68 . Therefore, the oil O flowing into the recess 64 can be easily guided to the through hole 68 along the inclined surface 64a. Here, as described above, the inclination of the inclined surface 64a also functions as a draft angle when removing the portion of the mold for molding the recess 64. Therefore, the recess 64 can be easily formed by die-casting, and the oil O can more easily flow from the inside of the first housing 61 to the inside of the second housing 62.

Further, according to the present embodiment, the entire recess 64 overlaps with the through hole 68 when viewed in the direction in which the first housing 61 and the second housing 62 are lined up. Therefore, the recess 64 can be provided only in a portion necessary for expanding the through hole 68 downward. Thereby, although the through hole 68 is enlarged by the recess 64, the size of the recess 64 can be made relatively small. Therefore, compared to, for example, a case where the recess 64 extends further in the front-rear direction than the through hole 68, the area in which the recess 64 is provided can be made smaller in the first bottom 61a. Therefore, the portion where the thickness of the first bottom portion 61a is reduced due to the recessed portion 64 can be reduced. This makes it easy to ensure the strength of the first bottom portion 61a without increasing the thickness of the first bottom portion 61a.

Further, according to the present embodiment, the opening area of the opening 68c of the through hole 68 that opens into the inside of the first housing 61 is larger than the total opening area of the supply ports 11, 12, and 24a. Therefore, it is easier to increase the amount of oil O flowing into the second housing 62 from the through hole 68 than the amount of oil O flowing into the first housing 61 from the supply ports 11, 12, 24a. This allows the oil O to flow more easily from the inside of the first housing 61 to the inside of the second housing 62, and prevents too much oil O from accumulating inside the first housing 61.

Further, according to the present embodiment, the drive device 1 includes a cooler 97 as an auxiliary device fixed to the outer surface of the first housing 61. Therefore, the first housing 61 in which the recess 64 is provided in the first bottom portion 61a can be reinforced by the cooler 97 attached to the outer surface. Thereby, even if the recess 64 is provided in the first bottom portion 61a, the strength of the first housing 61 can be easily ensured.

Further, according to the present embodiment, the cooler 97 as an auxiliary device has a flow path 97a connected to the inside of the second housing 62, and the outer surface of the portion of the first bottom portion 61a where the recess 64 is provided. Fixed. Therefore, it is easy to arrange the cooler 97 near the through hole 68 to which the recess 64 is connected. This makes it easy to shorten the path through which the oil O flowing into the second housing 62 through the through hole 68 flows into the flow path 97a. Therefore, it is easy to reduce the loss of the oil O from the inside of the second housing 62 to the flow path 97a of the cooler 97. Furthermore, by fixing the cooler 97 to the outer surface of the portion of the first bottom portion 61a where the recess 64 is provided, the strength of the first bottom portion 61a reduced by the recess 64 can be more suitably reinforced.

Further, according to the present embodiment, the first housing 61 houses the motor 2 therein, and the second housing 62 houses the transmission device 3 therein. Therefore, the oil O sent to the inside of the first housing 61 to cool the motor 2 can be suitably returned to the inside of the second housing 62 via the through hole 68.

(Modified example of the first embodiment)
As shown in FIG. 5, the inner surface of the recess 164 in the first bottom 161a of the first housing 161 of this modification includes a curved surface. Therefore, the oil O that has flowed into the recess 164 can easily flow into the through hole 68 along the curved surface. This allows the oil O to flow more easily from the inside of the first housing 161 to the inside of the second housing 62.

A lower surface 164a of the inner surface of the recess 164 and a right surface 164b of the inner surface of the recess 164 form a curved surface that is smoothly connected and concave downward when viewed in the front-rear direction. The inner surface of the recess 164 is, for example, a curved surface that is smoothly connected as a whole. The other configurations of the first housing 161 can be made similar to the other configurations of the first housing 61 described above.

<Second embodiment>
As shown in FIG. 6, in this embodiment, the through hole 268 of the partition wall 263 passes through the lower end of the partition wall 263 in a direction obliquely inclined in a direction perpendicular to the axial direction. Among the inner surfaces of the through hole 268, surfaces located on both sides in the vertical direction are inclined surfaces 268e and 268f that are located downward from the first housing 261 toward the second housing 62. The inclined surface 268e is a surface located on the upper side of the inner surface of the through hole 268. The inclined surface 268f is a surface located on the lower side of the inner surface of the through hole 268. For example, the inclined surface 268e and the inclined surface 268f are parallel to each other.

The bottom surface 261b of the first bottom portion 261a of the first housing 261 is, for example, a flat surface perpendicular to the vertical direction. In this embodiment, the inner surface of the recess 264 has an inclined surface 264a that is located lower toward the partition wall 263. The inclined surface 264a connects the bottom surface 261b and the inclined surface 268f. When viewed in the front-rear direction, the angle of inclination of the inclined surface 264a with respect to the axial direction is, for example, the same as the angle of inclination of the inclined surfaces 268e and 268f of the through hole 268 with respect to the axial direction. The inclined surface 264a and the inclined surface 268f form an inclined surface that is smoothly connected and inclined at a constant angle of inclination. The recessed portion 264 is provided, for example, over the entire first bottom portion 261a in the front-rear direction. The other configurations of this embodiment can be made similar to the other configurations of the first embodiment.

According to this embodiment, the through hole 268 has an inclined surface 268f located on the lower side as it goes from the first housing 261 to the second housing 62, and the recess 264 has an inclined surface 264a connected to the inclined surface 268f of the through hole 268. has. Therefore, the oil O in the first housing 261 can be easily guided into the second housing 62 along the inclined surface 264a and the inclined surface 268f. This allows the oil O to flow more easily from the inside of the first housing 261 to the inside of the second housing 62.

The present invention is not limited to the above-described embodiments, and other configurations may be adopted within the scope of the technical idea of the present invention. In the embodiment described above, a case has been described in which the fluid flowing from the inside of the first housing to the inside of the second housing through the through hole is oil O, but the present invention is not limited to this. The fluid is not particularly limited. The fluid may be, for example, an insulating liquid or water. When the fluid is water, the surface of the stator may be insulated.

The shape of the recess is not particularly limited. When viewed in the direction in which the first housing and the second housing are lined up, the interior of the recess may be, for example, semicircular, arcuate, or polygonal. The shape of the through hole is not particularly limited. The through hole may be a circular hole, a rectangular hole, or an arcuate hole.

If the inside of the recess is connected to the inside of the through hole, the end of the through hole on one side in the predetermined direction may be located on the other side of the recess in the predetermined direction than the end of the recess on the one side in the predetermined direction. good. For example, the lower end of the through hole 68 in the first embodiment described above may be located above the lower end of the recess 64.

The surface on the other side in the predetermined direction of the second bottom part may be located at the same position in the predetermined direction as the surface on the other side of the first bottom part in the predetermined direction, It may be located on the other side in the predetermined direction than the surface on the other side in the predetermined direction. For example, in the first embodiment described above, a portion of the bottom surface 62b of the second bottom portion 62a may be located at the same position in the vertical direction as the bottom surface 61b of the first bottom portion 61a, or may be located above the bottom surface 61b. Good too. Moreover, the other surface of the second bottom in the predetermined direction may be connected to an edge of an opening of the through hole that opens into the inside of the second housing. For example, in the first embodiment described above, the bottom surface 62b is located at the same position in the vertical direction as the lower end of the through hole 68, and the right end of the bottom surface 62b is the lower edge of the opening 68d of the through hole 68. May be connected.

The members housed inside the first housing and the members housed inside the second housing are not particularly limited. The first housing may house a transmission device therein. The second housing may house the motor therein. The auxiliary equipment fixed to the outer surface of the first housing is not particularly limited. The auxiliary machine fixed to the outer surface of the first housing may be an oil pump or an electric actuator.

The predetermined direction is not particularly limited. The predetermined direction may be a horizontal direction orthogonal to the vertical direction. In this case, for example, the fluid in the second housing may be sucked by the pump to cause a flow of fluid from the first housing into the second housing. Also in this case, by providing the recessed portion in the first bottom portion, the through hole can be enlarged, and the fluid can easily flow from the inside of the first housing to the inside of the second housing. In this case, the first bottom portion is a portion of the first housing located on one side in the horizontal direction, and the second bottom portion is a portion of the second housing located on one side in the horizontal direction.

The drive device is not particularly limited as long as it is a device that can move a target object using a motor as a power source. The drive device may not include a transmission mechanism. The motor torque may be output directly to the target from the motor shaft. In this case, the drive device corresponds to the motor itself. The direction in which the motor shaft extends is not particularly limited. The motor shaft may extend vertically. Note that in this specification, "the motor shaft extends in the horizontal direction perpendicular to the vertical direction" includes not only the case in which the motor shaft extends strictly in the horizontal direction, but also the case in which the motor shaft extends in the substantially horizontal direction. That is, in this specification, "the motor shaft extends in the horizontal direction perpendicular to the vertical direction" may mean that the motor shaft is slightly inclined with respect to the horizontal direction. Further, in the above-described embodiment, a case has been described in which the drive device does not include an inverter unit, but the present invention is not limited to this. The drive device may include an inverter unit. In other words, the drive device may have an integral structure with the inverter unit.

The use of the drive device is not particularly limited. The drive device does not have to be mounted on the vehicle. The configurations described above in this specification can be combined as appropriate within a mutually consistent range.

DESCRIPTION OF SYMBOLS 1... Drive device, 2... Motor, 3... Transmission device, 6... Housing, 10... Pipe (supply part), 11, 12, 24a... Supply port, 24... Rotor body (supply part), 61, 161, 261... First housing, 61a, 161a, 261a...first bottom part, 62...second housing, 62a...second bottom part, 63,263...partition wall, 64,164,264...recessed part, 64a...inclined surface, 68,268...penetration Hole, 68c, 68d, 268c...Opening, 70...Temperature sensor, 97...Cooler (auxiliary equipment), 97a...Flow path, O...Oil (fluid)

Claims (15)

motor and
a housing that houses the motor therein;
Equipped with
The motor has a stator,
The housing includes:
a first housing;
a second housing connected to the first housing;
a partition wall separating the inside of the first housing and the inside of the second housing;
has
The stator has a stator core,
The first housing has a first bottom portion located on one side in a predetermined direction,
The second housing has a second bottom portion located on one side in the predetermined direction,
At least a portion of the second bottom surface on the other side in the predetermined direction is located on one side in the predetermined direction than the first bottom surface on the other side in the predetermined direction,
The first bottom portion has a concave portion recessed on one side in the predetermined direction at a position adjacent to the partition wall,
The stator core has a portion located on the other side of the predetermined direction than the recess and facing the recess in the predetermined direction,
The partition wall has a through hole that connects the inside of the first housing and the inside of the second housing,
The inside of the recess is connected to the inside of the through hole. The predetermined direction is a vertical direction,
The drive device according to claim 1, wherein one side in the predetermined direction is a vertically lower side. 3. The drive device according to claim 2, wherein a vertically upper surface of the second bottom portion is located entirely below a vertically upper surface of the first bottom portion. 4. The drive device according to claim 2, wherein the opening of the through hole that opens into the second housing opens obliquely downward in the vertical direction. The drive device according to claim 1 , wherein an end of the through hole on the other side in the predetermined direction is located on the other side in the predetermined direction than the first bottom portion. The drive device according to any one of claims 1 to 5, wherein one end of the recess in the predetermined direction opens into the second housing through the through hole. The drive device according to any one of claims 1 to 6, wherein the recess is a groove extending to the through hole. The drive device according to any one of claims 1 to 7, wherein the surface located on the lower side in the vertical direction among the inner surfaces of the recessed portion is an inclined surface located on the lower side in the vertical direction toward the through hole. . The drive device according to any one of claims 1 to 8, wherein the recess entirely overlaps the through hole when viewed in the direction in which the first housing and the second housing are lined up. further comprising a supply part having a supply port for supplying fluid into the first housing,
The drive device according to any one of claims 1 to 9, wherein an opening area of an opening portion of the through hole that opens into the inside of the first housing is larger than a total opening area of the supply port. The drive device according to any one of claims 1 to 10, wherein an inner surface of the recess includes a curved surface. Further comprising a temperature sensor capable of detecting the temperature of the motor,
The drive device according to any one of claims 1 to 11, wherein the temperature sensor is located vertically above the through hole. The drive device according to any one of claims 1 to 12, further comprising an auxiliary machine fixed to an outer surface of the first housing. The drive device according to claim 13, wherein the auxiliary device has a flow path connected to the inside of the second housing and is fixed to an outer surface of a portion of the first bottom where the recess is provided. . further comprising a transmission device connected to the motor,
the first housing accommodates the motor therein;
The drive device according to any one of claims 1 to 14, wherein the second housing houses the transmission device therein.

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