Transmission mechanism and drive device

Abstract

To provide a transmission mechanism and a driving device capable of supplying fluid scooped up by a gear to a desired part.SOLUTION: The transmission mechanism includes a power transmission part and a housing. A direction orthogonal to the up-down direction is defined as a first direction, and a direction orthogonal to the up-down direction and the first direction is defined as a second direction. The power transmission unit includes a first gear that rotates about a first axis extending in the first direction, a second gear and a third gear that rotate about a second axis, and a fourth gear that rotates about a third axis. The third axis is located on one side in the second direction relative to the first axis. A first fluid guide extending in the first direction is provided on an inner surface of the gear accommodation portion. At least a part of the first fluid guide is located above the meshing portion between the first gear and the second gear and on the other side in the second direction with respect to the first axis, and overlaps the fourth gear in the radial direction. The first fluid guide includes a first inclined portion inclined downward from the other side toward the one side in the second direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a transmission mechanism and a drive device. [Background technology]

[0002] In recent years, development of transmission mechanisms for drive units mounted on electric vehicles has progressed. In such transmission mechanisms, fluid may be stored in the internal space of the housing to efficiently lubricate the gears. Patent Document 1 discloses a structure in which oil stored at the bottom of the case is scooped up by the rotation of the gears and supplied to an oil path, and then from the oil path to the bearings. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-59477 Summary of the Invention [Problem to be solved by the invention]

[0004] In the transmission mechanism, the arrangement of each gear is determined by comprehensively considering the size of each gear, the distance from the liquid surface, the size of the housing, etc. However, depending on the arrangement of the gears, there are cases where the fluid cannot be sufficiently supplied to, for example, the meshing portions of each gear due to the gears stirring up the fluid.

[0005] In view of the above-mentioned problems, one aspect of the present invention aims to provide a transmission mechanism and a drive device that can supply fluid scooped up by gears to a desired location. [Means for solving the problem]

[0006] A transmission mechanism according to one embodiment of the present invention transmits power from a motor. The transmission mechanism includes a power transmission unit and a housing having a gear accommodating portion that accommodates the power transmission unit. A first direction is a direction perpendicular to the up-down direction, and a second direction is a direction perpendicular to both the up-down direction and the first direction. The power transmission unit includes a first gear that rotates about a first axis extending in the first direction, a second gear that meshes with the first gear and rotates about a second axis extending parallel to the first axis, a third gear that rotates about the second axis, and a fourth gear that meshes with the third gear and rotates about a third axis extending parallel to the first axis. The third axis is located to one side of the first axis in the second direction. A first fluid guide extending in the first direction is provided on an inner surface of the gear accommodating portion. At least a portion of the first fluid guide is located above an engagement portion between the first gear and the second gear and on the other side of the first axis in the second direction, and overlaps with the fourth gear in the radial direction. The first fluid guide has a first inclined portion that inclines downward as it moves from the other side to one side in the second direction.

[0007] A drive device according to one embodiment of the present invention includes the above-described transmission mechanism and the motor. [Effects of the Invention]

[0008] According to one aspect of the present invention, it is possible to provide a transmission mechanism and a drive device that can supply fluid scooped up by a gear to a desired location. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a conceptual diagram of a drive device according to one embodiment. [Figure 2] FIG. 2 is a view of a power transmission unit and a part of a housing according to an embodiment, viewed from the other side in the first direction. [Figure 3] FIG. 3 is a view of a power transmission unit and a part of a housing according to an embodiment, viewed from one side in a first direction. [Figure 4] FIG. 4 is a perspective view of a first fluid guide according to one embodiment. [Figure 5] FIG. 5 is a perspective view of a second fluid guide according to one embodiment. [Figure 6] FIG. 6 is a perspective view of the third fluid guide and the fourth fluid guide of one embodiment. [Figure 7] FIG. 7 is a perspective view of the first fluid guide of the first modification. [Figure 8] FIG. 8 is a perspective view of the fourth fluid guide of the second modification. DETAILED DESCRIPTION OF THE INVENTION

[0010] A drive unit according to an embodiment of the present invention will be described below with reference to the drawings. In the following description, the vertical direction is defined based on the positional relationship when the drive unit 100 of this embodiment is mounted on a vehicle positioned on a horizontal road surface.

[0011] In the drawings, an XYZ coordinate system is shown as a three-dimensional Cartesian coordinate system as appropriate. In the XYZ coordinate system, the Z-axis direction is the up-down direction. The up-down direction is, for example, the vertical direction. In the following embodiments, the +Z side is the upper side in the vertical direction, and the -Z side is the lower side in the vertical direction. In this embodiment, 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 fore-and-aft direction of the vehicle on which the drive unit 100 is mounted. 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, i.e., the vehicle width direction.

[0012] In this specification, a direction perpendicular to the up-down direction Z is referred to as a first direction Y, and a direction perpendicular to the up-down direction Z and the first direction is referred to as a second direction X. In this specification, the first direction Y is the left-right direction of the vehicle, and the second direction X is the front-rear direction of the vehicle.

[0013] The first axis J1, second axis J2, and third axis J3 shown in each drawing as appropriate are parallel to one another and extend in a first direction Y. In the following description, one side in the first direction refers to the +Y side in the direction along the Y axis, and the other side in the first direction refers to the -Y side in the direction along the Y axis. Furthermore, one side in the second direction refers to the -X side in the direction along the X axis, and the other side in the second direction refers to the +X side in the direction along the X axis. Note that in this specification, the up-down direction refers to the up-down direction from a single viewpoint and does not necessarily refer to the vertical direction.

[0014] FIG. 1 is a conceptual diagram of a driving device 100. As shown in FIG. The drive unit 100 of this embodiment is mounted on an electric vehicle (EV) and used as its power source. The drive unit 100 may also be mounted on a vehicle that uses a motor as a power source, such as a hybrid electric vehicle (HEV) or a plug-in hybrid electric vehicle (PHV).

[0015] 1, the driving device 100 of this embodiment includes a motor 2 and a transmission mechanism 4 that transmits the power of the motor 2. The driving device 100 may further include an inverter. The transmission mechanism 4 includes a power transmission unit 3 and a gear accommodating portion 6b of a housing 6.

[0016] <Motor> The motor 2 of this embodiment is a three-phase AC motor. The motor 2 of this embodiment functions both as an electric motor and as a generator. The motor 2 may have either the function of an electric motor or the function of a generator.

[0017] The motor 2 is located on the other side (-Y) in the first direction of the power transmission unit 3. The motor 2 includes a rotor 20 that rotates about a first axis J1 that extends in the first direction Y, and a stator 25 that is located radially outside the rotor 20. The motor 2 of this embodiment is an inner rotor motor in which the rotor 20 is disposed inside the stator 25. However, the motor 2 may also be an outer rotor motor. In other words, the configuration of the motor 2 is not limited to this embodiment.

[0018] The rotor 20 rotates about a first axis J1 extending in the first direction Y. The rotor 20 has a motor shaft 21, a rotor core 24 fixed to the outer peripheral surface of the motor shaft 21, and a rotor magnet (not shown) fixed to the rotor core. The motor 2 may be a type of motor such as an induction motor in which the rotor 20 does not have a rotor magnet.

[0019] The motor shaft 21 extends in the first direction Y around the first axis J1. The motor shaft 21 rotates around the first axis J1. The first shaft 46 of the power transmission unit 3 is connected to the end of the motor shaft 21 on one side (+Y) in the first direction. This allows the torque of the rotor 20 to be transmitted to the power transmission unit 3. The motor shaft 21 is rotatably supported by the housing 6 via bearings B5 and B6. The motor shaft 21 and the first shaft 46 may be parts of a single shaft.

[0020] The stator 25 is held by the housing 6. The stator 25 surrounds the rotor 20 from the radially outer side. The outer peripheral surface of the stator 25 faces the inner peripheral surface of the housing 6. The stator 25 has an annular stator core 27 centered on the first axis J1, and coils 26 attached to the stator core 27. The stator core 27 is fixed to the housing 6.

[0021] Coil 26 is attached to each tooth of stator core 27 via an insulator (not shown). Coil 26 is made up of a plurality of coil wires. Coil 26 may also be made up of a plurality of rod-shaped conductors connected together.

[0022] <Transmission mechanism> The power transmission unit 3 is located on one side (+Y) in the first direction of the motor 2. The power transmission unit 3 has a plurality of gears 41, 42, 43, 51 that transmit the power of the motor 2. The power transmission unit 3 reduces the rotational speed output from the motor 2 and increases the torque output from the motor 2, and outputs it from the output shaft 55.

[0023] The power transmission unit 3 has a first shaft 46, a first gear 41, a second shaft 45, a second gear 42, a third gear 43, a differential device 5, and an output shaft 55. The first shaft 46, the second shaft 45, and the output shaft 55 extend parallel to one another. The first gear 41 and the second gear 42 are located on one side (+Y) in the first direction relative to the third gear 43 and the ring gear 51.

[0024] The first shaft 46 and the first gear 41 are disposed about the first axis J1. The first shaft 46 extends in the first direction Y about the first axis J1. The first shaft 46 is connected to the motor shaft 21 at its end on the other side (-Y) in the first direction. The first gear 41 is provided on the outer peripheral surface of the first shaft 46. The first gear 41 rotates together with the first shaft 46 about the first axis J1. The first shaft 46 is rotatably supported by the housing 6 via bearings B1 and B2.

[0025] The second shaft 45, the second gear 42, and the third gear 43 are disposed about a second axis J2 that extends parallel to the first axis J1. The second shaft 45 extends in the first direction Y around the second axis J2. The second shaft 45 is rotatably supported by the housing 6 via bearings B3 and B4. The second gear 42 and the third gear 43 are provided on the outer circumferential surface of the second shaft 45 and spaced apart from each other in the first direction Y. The second gear 42 and the third gear 43 rotate together with the second shaft 45 around the second axis J2. The second gear 42 meshes with the first gear 41. The third gear 43 meshes with a ring gear 51 of the differential device 5.

[0026] The differential device 5 has a ring gear (fourth gear) 51, a differential mechanism 5a, and a differential case (not shown). That is, the power transmission unit 3 has the ring gear 51 and the differential mechanism 5a. The ring gear 51 meshes with the third gear 43 and rotates about a third axis J3 extending parallel to the first axis J1. The ring gear 51 is the gear with the largest diameter among the multiple gears in the power transmission unit 3. The differential case accommodates the differential mechanism 5a therein. In this embodiment, the differential case is fixed to the ring gear 51. The differential case is also supported by the housing 6 via a bearing B7. That is, the ring gear 51 is rotatably supported by the housing 6 via the differential case and the bearing B7. Note that a differential case need not be provided, and the output shaft 55 may be supported by the housing 6 via the bearing B7. The rotation of the ring gear 51 is transmitted to the differential mechanism 5a and further transmitted from the output shaft 55 connected to the differential mechanism 5a. When the vehicle turns, the differential mechanism 5a transmits torque to the output shafts 55 for both the left and right wheels while absorbing the speed difference between the left and right wheels. The output shafts 55 extend along the third axis J3. The output shafts 55 are connected to the wheels.

[0027] Fig. 2 is a view of the power transmission unit 3 and a portion of the housing 6 as seen from one side (+Y) in the first direction. Fig. 3 is a view of the power transmission unit 3 and a portion of the housing 6 as seen from the other side (-Y) in the first direction.

[0028] As shown in FIGS. 2 and 3, the first axis J1 is located on the other side in the second direction (+X) of the second axis J2 and the third axis J3. The second axis J2 is located between the first axis J1 and the third axis J3 in the second direction X. The third axis J3 is located on one side in the second direction (-X) of the first axis J1 and the second axis J2. In the power transmission unit 3, the power of the motor 2 is transmitted in the following order: the gear rotating about the first axis J1, the gear rotating about the second axis J2, and the gear rotating about the third axis J3. According to this embodiment, the gears of the power transmission unit 3 are aligned in the second direction X, thereby enabling the size of the power transmission unit 3 in the up-down direction Z to be reduced.

[0029] The first axis J1 is located below (-Z) the second axis J2 and the third axis J3. The second axis J2 is located above (+Z) the first axis J1 and the third axis J3. The third axis J3 is located between the first axis J1 and the third axis J3 in the vertical direction Z. The ring gear 51 has a larger diameter than the other gears. According to this embodiment, since the third axis J3 is located between the first axis J1 and the second axis J2 in the vertical direction Z, other gears are less likely to protrude above or below the upper and lower ends of the ring gear 51. This allows the power transmission unit 3 to be made smaller in size in the vertical direction Z.

[0030] <Housing> 1, the housing 6 has a motor accommodating portion 6a that accommodates the motor 2 and a gear accommodating portion 6b that accommodates the power transmission unit 3. The gear accommodating portion 6b is located on one side (+Y) in the first direction of the motor accommodating portion 6a.

[0031] A fluid O is stored within the housing 6. The housing 6 is also provided with a flow path 90. The fluid O circulates within the housing 6 through the flow path 90. In this embodiment, the fluid O functions as a refrigerant for cooling the motor 2 and as a lubricant for the power transmission unit 3. It is preferable to use, as the fluid O, an oil equivalent to a lubricating oil for automatic transmissions (ATF: Automatic Transmission Fluid) with a relatively low viscosity, in order to function as a lubricating oil and a cooling oil.

[0032] The fluid O accumulates in a lower region of the internal space of the housing 6. That is, the fluid O accumulates in the lower region of the housing 6. Hereinafter, the lower region of the housing 6 where the fluid O is accumulated will be referred to as the accumulation portion P. In the housing 6 of this embodiment, the bottom surface of the gear accommodating portion 6b is located lower (-Z) than the bottom surface of the motor accommodating portion 6a. Therefore, the accumulation portion P is provided in the lower region of the internal space of the gear accommodating portion 6b. However, the accumulation portion P may be provided across the lower regions of the motor accommodating portion 6a and the gear accommodating portion 6b. Note that, as long as the accumulation portion P is provided in the internal space of the gear accommodating portion 6b, the bottom surface of the gear accommodating portion 6b may be at the same vertical position as the bottom surface of the motor accommodating portion 6a or may be higher than the bottom surface of the motor accommodating portion 6a.

[0033] The ring gear 51 is immersed in the fluid O in the reservoir P. As the ring gear 51 rotates about the third axis J3, the fluid O in the reservoir P is scooped up and scattered into the internal space of the gear accommodating portion 6b. The fluid O scooped up by the ring gear 51 is supplied to each gear accommodated in the gear accommodating portion 6b and lubricates the gear tooth surfaces, etc.

[0034] As shown in FIG. 2, a first fluid guide 70, a second fluid guide 80, a third fluid guide 83, and a fourth fluid guide 87 are provided on the inner surface of the gear accommodating portion 6b in this embodiment. The first fluid guide 70, the second fluid guide 80, the third fluid guide 83, and the fourth fluid guide 87 guide the fluid O scooped up by the ring gear 51. In this embodiment, the first fluid guide 70, the second fluid guide 80, the third fluid guide 83, and the fourth fluid guide 87 are each rib-shaped and extend in the first direction Y. The first fluid guide 70, the second fluid guide 80, the third fluid guide 83, and the fourth fluid guide 87 will be described in detail later.

[0035] 1, the fluid O in the reservoir P passes through a flow path 90 and is sent to the internal space of the motor housing 6a and the internal space of the gear housing 6b. The fluid O sent to the internal space of the motor housing 6a flows over the surface of the motor 2 to cool it. The fluid O sent to the internal space of the gear housing 6b lubricates the gears of the power transmission unit 3 and the bearings that support the power transmission unit 3.

[0036] The housing 6 is formed by combining multiple members. The housing 6 of this embodiment has a housing main body 61, a motor cover 63, and a gear cover 62. The motor cover 63 is located on the other side (-Y) of the housing main body 61 in the first direction. The gear cover 62 is located on one side (+Y) of the housing main body 61 in the first direction. The housing main body 61 and the motor cover 63 are abutted in the first direction Y to form the motor accommodating section 6a. The housing main body 61 and the gear cover 62 are abutted in the first direction Y to form the gear accommodating section 6b.

[0037] In this embodiment, the housing 6 is described as being composed of the above-mentioned three members (housing main body 61, motor cover 63, and gear cover 62) that are separable from one another. However, the member configuration of the housing 6 is not limited to this embodiment. For example, each member of the housing 6 may be further separable. Furthermore, the housing 6 may further have a portion that houses an inverter (not shown), for example.

[0038] The housing 6 has a first wall portion 65, a second wall portion 66, a third wall portion 67, a first surrounding portion 68, and a second surrounding portion 69. The first wall portion 65, the second wall portion 66, the third wall portion 67, the first surrounding portion 68, and the second surrounding portion 69 are parts of the housing main body 61, the motor cover 63, and the gear cover 62 described above. The first wall portion 65, the second wall portion 66, and the third wall portion 67 extend along a plane perpendicular to the first axis J1. The first surrounding portion 68 surrounds the power transmission unit 3 from the radially outer side of the first axis J1, the second axis J2, and the third axis J3. The second surrounding portion 69 surrounds the motor 2 from the radially outer side of the first axis J1.

[0039] The first wall portion 65 is provided on the housing main body 61. The first wall portion 65 separates the internal space of the motor accommodating portion 6a from the internal space of the gear accommodating portion 6b. The first wall portion 65 constitutes a part of the motor accommodating portion 6a and the gear accommodating portion 6b. The first wall portion 65 covers the motor 2 from one side (+Y) in the first direction. The first wall portion 65 also covers the power transmission portion 3 from the other side (-Y) in the first direction.

[0040] The first wall portion 65 is provided with a first through hole 65a, a second through hole 65b, a third through hole 65c, and a fourth through hole 65d. The first through hole 65a, the second through hole 65b, the third through hole 65c, and the fourth through hole 65d penetrate the first wall portion 65 in the first direction Y. The first through hole 65a connects the reservoir P with the suction port of the pump 8 (described later). The second through hole 65b connects the lower part of the internal space of the motor accommodating portion 6a with the internal space of the gear accommodating portion 6b. The third through hole 65c accommodates a connecting portion between the motor shaft 21 and the first shaft 46, a bearing B5 that holds the motor shaft 21, and a bearing B2 that holds the first shaft 46. The fourth through hole 65d connects the upper part of the internal space of the motor accommodating portion 6a with the upper part of the internal space of the gear accommodating portion 6b.

[0041] The second wall portion 66 is provided on the gear cover 62. The second wall portion 66 constitutes a part of the gear accommodating portion 6b. That is, the gear accommodating portion 6b has the second wall portion 66. The second wall portion 66 covers the power transmission portion 3 from one side (+Y) in the first direction. The second wall portion 66 faces the first wall portion 65 across the internal space of the gear accommodating portion 6b.

[0042] The third wall portion 67 is provided on the motor cover 63. The third wall portion 67 constitutes a part of the motor accommodating portion 6a. The third wall portion 67 covers the motor 2 from the other side (-Y) in the first direction. The third wall portion 67 faces the first wall portion 65 across the internal space of the motor accommodating portion 6a.

[0043] The first surrounding portion 68 extends in a cylindrical shape along the first direction Y. The first surrounding portion 68 connects the first wall portion 65 and the second wall portion 66. In this embodiment, the first surrounding portion 68 has a first surrounding wall 68a and a second surrounding wall 68b. The first surrounding wall 68a is a part of the housing main body 61. The first surrounding wall 68a protrudes from the first wall portion 65 to one side in the first direction (+Y). The second surrounding wall 68b is a part of the gear cover 62. The second surrounding wall 68b protrudes from the second wall portion 66 to the other side in the first direction (-Y).

[0044] The first surrounding wall 68a has a first opposing surface 68f facing one side in the first direction (+Y). The second surrounding wall 68b has a second opposing surface 68g facing the other side in the first direction (-Y). The first opposing surface 68f and the second opposing surface 68g face each other in the first direction Y. The first opposing surface 68f and the second opposing surface 68g contact each other via a sealing member such as a gasket. This connects the first surrounding wall 68a and the second surrounding wall 68b to each other.

[0045] The second surrounding portion 69 is provided in the housing main body 61. The second surrounding portion 69 constitutes a part of the motor accommodating portion 6a. The second surrounding portion 69 is cylindrical and extends along the first direction Y with the first axis J1 as its center. The second surrounding portion 69 connects the first wall portion 65 and the third wall portion 67. The second surrounding portion 69 surrounds the motor 2 from the radial outside of the first axis J1.

[0046] <Flow path> 1, a flow path 90 is provided in the housing 6. The flow path 90 is a circulation path through which the fluid O flows. That is, the fluid O circulates through the flow path 90 provided in the housing 6. It is sufficient that at least a portion of the flow path 90 is provided in the housing 6.

[0047] A pump 8, a cooler 9, a first supply pipe 93A, and a second supply pipe (supply unit) 94A are arranged in the flow path 90. In the drive device 100 of this embodiment, the pump 8 and the cooler 9 are arranged on the outer surface of the housing 6, and the first supply pipe 93A and the second supply pipe 94A are arranged in the internal space of the housing 6. The pump 8 and the cooler 9 may also be arranged in the internal space of the housing 6.

[0048] The pump 8 sucks and pressure-feeds the fluid O from the reservoir P through the first through-hole 65a. The cooler 9 cools the fluid O in the flow path 90. In this embodiment, a refrigerant (not shown) flows inside the cooler 9. The cooler 9 in this embodiment is a heat exchanger that exchanges heat between the fluid O and the refrigerant.

[0049] The first supply pipe 93A is disposed in the internal space of the motor accommodating portion 6a. The first supply pipe 93A extends along the first direction Y. An end portion of the first supply pipe 93A on one side (+Y) in the first direction is inserted into the fourth through-hole 65d and supported by the first wall portion 65. An end portion of the first supply pipe 93A on the other side (-Y) in the first direction is supported by the motor cover 63. The first supply pipe 93A is provided with a plurality of supply ports that open toward the stator 25. The first supply pipe 93A supplies a portion of the fluid O flowing inside it to the motor 2 from the supply ports.

[0050] The second supply pipe 94A is disposed in the internal space of the gear accommodating portion 6b. The second supply pipe 94A extends along the first direction Y. An end portion of the second supply pipe 94A on one side (+Y) in the first direction is supported by the gear cover 62. An end portion of the second supply pipe 94A on the other side (-Y) in the first direction is inserted into the fourth through-hole 65d and supported by the first wall portion 65. As a result, the second supply pipe 94A is connected to the first supply pipe 93A via the fourth through-hole 65d. The second supply pipe 94A of this embodiment is provided with a supply port 94h. The second supply pipe 94A supplies at least a portion of the fluid O flowing therethrough from the supply port 94h to a first fluid guide 70, which will be described later.

[0051] 2, a protrusion 94b is provided on the outer periphery of the second supply pipe 94A. The protrusion 94b is arranged along the first wall 65. An insertion pin 94c extending in the first direction Y is provided on a surface of the protrusion 94b facing the other side in the first direction (-Y). Furthermore, a supply pipe fixing portion 65k is provided on a surface of the first wall 65 facing one side in the first direction (+Y). The supply pipe fixing portion 65k has a recess (not shown) recessed from a surface of the first wall portion 65 facing one side in the first direction (+Y) toward the other axial side (-Y). The supply pipe fixing portion 65k is located above a first fluid guide 70 (described later). The supply pipe fixing portion 65k is also connected to the first fluid guide 70 (described later). This increases the rigidity of the supply pipe fixing portion 65k. The insertion pin 94c is inserted into the recess of the supply pipe fixing portion 65k. This prevents the second supply pipe 94A from rotating around the axis of the second supply pipe 94A, making it easier to determine the opening direction of the supply port 94h of the second supply pipe 94A.

[0052] As shown in FIG. 1 , the flow path 90 of this embodiment has an intake flow path section 91a, a connecting flow path section 91b, an in-wall flow path section 92, a first in-pipe flow path section 93, and a second in-pipe flow path section 94. The intake flow path section 91a is a flow path inside the first through-hole 65a and connects the reservoir P and the pump 8. The connecting flow path section 91b connects the pump 8 and the cooler 9. The in-wall flow path section 92 is provided inside the wall of the motor housing section 6a and connects the cooler 9 and the first supply pipe 93A. The first in-pipe flow path section 93 is a flow path inside the first supply pipe 93A. The second in-pipe flow path section 94 is a flow path inside the second supply pipe 94A.

[0053] The flow path 90 of the present embodiment is merely an example, and the flow path 90 may further include other flow path portions. As an example, the flow path 90 may include a flow path portion that is connected to the downstream side of the second in-pipe flow path portion 94 and supplies the fluid O to a bearing held by the gear cover 62.

[0054] The fluid O passes through the intake passage 91a and is sucked into the pump 8. Then, it passes through the connecting passage 91b and is sent to the cooler where it is cooled. The fluid O then passes through the in-wall passage 92 and reaches the first supply pipe 93A. The fluid O supplied to the first supply pipe 93A flows through a first in-pipe passage 93 provided inside the first supply pipe 93A. A portion of the fluid O flowing through the first in-pipe passage 93 is supplied to the motor 2 via a supply port provided in the first supply pipe 93A. The fluid O supplied to the motor 2 and dripping downward flows into the reservoir P of the gear housing 6b via the second through-hole 65b. The downstream end of the first in-pipe passage 93 is connected to the second in-pipe passage 94 via the fourth through-hole 65d. A portion of the fluid O that flows into the second in-pipe passage 94 is supplied to the first fluid guide 70 (described later) via a supply port 94h provided in the second supply pipe 94A.

[0055] <Route> As shown in FIG. 2 , when the power transmission unit 3 is viewed from one side (+Y) in the first direction, the direction in which the ring gear 51 rotates clockwise about the third axis J3 is defined as a first rotation direction R1, and the direction in which the ring gear 51 rotates counterclockwise is defined as a second rotation direction R2. In this embodiment, when the ring gear 51 rotates in the first rotation direction R1, the vehicle on which the drive unit 100 is mounted moves forward, and when the ring gear 51 rotates in the second rotation direction R2, the vehicle on which the drive unit 100 is mounted moves backward. However, the traveling direction of the vehicle relative to the rotation direction of the ring gear 51 in this embodiment is merely an example, and the relationship between the rotation direction of the ring gear 51 and the traveling direction of the vehicle is not limited to this embodiment. For example, when the ring gear 51 rotates in the first rotation direction R1, the vehicle on which the drive unit 100 is mounted moves backward, and when the ring gear 51 rotates in the second rotation direction R2, the vehicle on which the drive unit 100 is mounted moves forward.

[0056] The ring gear 51 rotating in the first rotation direction R1 has a portion on the other side in the second direction (+X) relative to the third axis J3 moving upward, and the portion on the other side in the second direction (+X) relative to the third axis J3 scoops up the fluid O in the storage section P. The ring gear 51 rotating in the second rotation direction R2 has a portion on one side in the second direction (-X) relative to the third axis J3 moving upward, and the portion on the one side in the second direction (-X) relative to the third axis J3 scoops up the fluid O in the storage section P.

[0057] The main flow of the fluid O after being stirred up by the ring gear 51 rotating in the first rotation direction R1 will be described as a first path F1, a second path F2, and a third path F3. The main flow of the fluid O after being stirred up by the ring gear 51 rotating in the second rotation direction R2 will be described as a fourth path F4.

[0058] The first path F1 is a path along which the fluid O travels from the reservoir P to the first fluid guide 70. A portion of the first path F1 extends upward and toward the other side (+X) of the second direction of the third axis J3, and is located between the first axis J1 and the second axis J2. A portion of the first path F1 is located in a region that overlaps with the ring gear 51 in the radial direction. A portion of the first path F1 is located in a region that overlaps with the second gear 42 in the first direction Y.

[0059] In this specification, when a specific portion or region "overlaps with a gear in the radial direction," it means that the portion or region overlaps with the gear in the radial direction of the gear.

[0060] The second path F2 is a path through which the fluid O changes direction when it strikes the second fluid guide 80 from the reservoir P and reaches the meshing portion 49, where the teeth of the first gear 41 and the teeth of the second gear 42 mesh with each other. The second path F2 extends upward and toward the other side (+X) of the second direction of the third axis J3 to reach the second fluid guide 80. A portion of the fluid O flowing through the second path F2 strikes a protrusion 81 of the second fluid guide 80, changes its flow direction toward one side (+Y) of the first direction, and reaches the meshing portion 49. The protrusion 81 will be described in detail later. At least a portion of the fluid flowing through the second path F2 until it reaches the protrusion 81 of the second fluid guide 80 passes through a region that radially overlaps with the ring gear 51. In the second path F2, at least a part of the fluid that has hit the convex portion 81 of the second fluid guide 80 passes through a region that does not overlap with the ring gear 51 in the radial direction.

[0061] The third path F3 is a path through which the fluid O travels from the reservoir P along the other side (+X) of the third axis J3 in the second direction until it reaches the third fluid guide 83. The third path F3 extends upward in the second direction X, passing between the first axis J1 and the third axis J3 and between the second axis J2 and the third axis J3. A portion of the third path F3 is located in a region that overlaps with the ring gear 51 in the radial direction. A portion of the third path F3 is located in a region that overlaps with the second gear 42 in the first direction Y.

[0062] The fourth path F4 is a path along which the fluid O travels from the reservoir P along one side (-X) in the second direction of the third axis J3 and above, until it reaches the third fluid guide 83. The fourth path F4 extends from one side (-X) in the second direction of the third axis J3 toward the upper side and the other side (+X) in the second direction. A portion of the fourth path F4 is located in a region radially overlapping with the ring gear 51.

[0063] The first path F1, the second path F2, the third path F3, and the fourth path F4 described above are merely representative paths for the fluid O being scooped up by the ring gear 51, and the fluid may flow through other paths. For example, as other paths, when the ring gear 51 rotates in the first rotational direction R1, the fluid O may be scooped up by the ring gear 51, pass above the second axis J2, and reach the first fluid guide 70.

[0064] <First fluid guide> 1, the first fluid guide 70 extends in the first direction Y. The first fluid guide 70 connects the first wall portion 65 and the second wall portion 66. In this embodiment, the first fluid guide 70 has a first portion 70A and a second portion 70B aligned in the first direction Y.

[0065] The first portion 70A extends from the first wall portion 65 toward one side (+Y) in the first direction. The first portion 70A radially overlaps with the third gear 43 and the ring gear 51. The second portion 70B extends from the second wall portion 66 toward the other side (-Y) in the first direction. The second portion 70B radially overlaps with the first gear 41 and the second gear 42. Note that the first portion 70A and the second portion 70B may radially overlap with any of the gears. Furthermore, as long as at least a portion of the first fluid guide 70 radially overlaps with the ring gear 51, either the first portion 70A or the second portion 70B may not radially overlap with any of the first gear 41, the second gear 42, the third gear 43, or the ring rear 51. Furthermore, even if the first portion 70A and the second portion 70B do not overlap with any gear in the radial direction, it is sufficient that at least a portion of the first fluid guide 70 overlaps with the ring gear 51.

[0066] The first portion 70A has a first tip surface 70f facing one side (+Y) in the first direction. The second portion 70B has a second tip surface 70g facing the other side (-Y) in the first direction. The first tip surface 70f and the second tip surface 70g face each other and are connected to each other in the first direction Y. That is, the second portion 70B is connected to the first portion 70A.

[0067] In this embodiment, the first tip surface 70f and the second tip surface 70g are in contact with each other. However, a gap may be provided between the first tip surface 70f and the second tip surface 70g to allow the fluid O to flow between the first portion 70A and the second portion 70B.

[0068] The first fluid guide 70 of this embodiment is configured by a first portion 70A protruding from the first wall portion 65 and a second portion 70B protruding from the second wall portion 66, with the tip surfaces 70f, 70g butting against each other. According to this embodiment, the lengths of the first portion 70A and the second portion 70B in the first direction can be shortened compared to when the entire first fluid guide protrudes in the first direction from only one of the first wall portion 65 and the second wall portion 66. This makes it easier to mold the protruding portions in the manufacturing process. In addition, by reducing the protruding lengths of the protruding portions (first portion 70A and second portion 70B), it becomes easier to move and adjust the orientation of the housing main body 61 and the gear cover 62 during the assembly process of the housing 6, thereby simplifying the assembly process.

[0069] In this embodiment, in the first direction Y, the first tip surface 70f of the first portion 70A is disposed on the same plane as the first opposing surface 68f of the first surrounding wall 68a. Therefore, when machining the housing main body 61, the first tip surface 70f and the first opposing surface 68f can be machined simultaneously by machining, such as milling. Similarly, in the first direction Y, the second tip surface 70g of the second portion 70B is disposed on the same plane as the second opposing surface 68g of the second surrounding wall 68b. When machining the gear cover 62, the second tip surface 70g and the second opposing surface 68g can be machined simultaneously. This prevents uneven gaps from occurring between the first opposing surface 68f and the second opposing surface 68g and between the first tip surface 70f and the second tip surface 70g when assembling the housing main body 61 and the gear cover 62. The first tip surface 70f and the second tip surface 70g do not necessarily have to be disposed on the same plane as the first opposing surface 68f and the second opposing surface 68g.

[0070] As shown in FIG. 3, a surface of the second wall portion 66 facing the other side (-Y) in the first direction is provided with a plurality of ribs 66a extending toward the other side (-Y) in the first direction. This increases the rigidity of the gear cover 62. The second portion 70B is connected to one of the plurality of ribs 66a. This increases the rigidity of the second portion 70B. In this embodiment, the rib 66a connected to the second portion 70B is a rib extending radially from a cylindrical bearing holder portion 66b centered on the second axis J2 in the second axis J2 direction.

[0071] As shown in FIG. 2, the first fluid guide 70 has a first inclined portion 71 and a second inclined portion 72. The first inclined portion 71 inclines downward as it moves from the other side (+X) in the second direction to one side (-X). The second inclined portion 72 is connected to at least a part of an end portion 71p of the first inclined portion 71 on one side (-X) in the second direction. The second inclined portion 72 inclines upward as it moves from the other side (+X) in the second direction to one side (-X).

[0072] As described above, at least a portion (first portion 70A) of the first fluid guide 70 of this embodiment overlaps with the ring gear 51 in the radial direction. Therefore, the first fluid guide 70 can efficiently receive the fluid O that is scooped up from the ring gear 51 and passes through the first path F1. Furthermore, at least a portion of the first fluid guide 70 of this embodiment is located above the meshing portion 49 between the first gear 41 and the second gear 42 and on the other side (+X) in the second direction of the first axis J1. Furthermore, the first inclined portion 71 inclines downward as it moves from the other side (+X) in the second direction to one side (-X). That is, according to this embodiment, the first inclined portion 71 inclines toward the meshing portion 49. As a result, the first inclined portion 71 can direct the fluid O received by the first fluid guide 70 toward the meshing portion 49 and supply it to the meshing portion 49. According to this embodiment, when the ring gear 51 rotates in the first rotation direction R1, the stirred-up fluid O can be supplied to the meshing portion 49 between the first gear 41 and the second gear 42, thereby lubricating and cooling the meshing portion 49.

[0073] In this embodiment, the first fluid guide 70 is located on the other side (+X) of the first axis J1 in the second direction. As described above, the third axis J3 is located on one side (-X) of the first axis J1 in the second direction. Therefore, the first fluid guide 70 is located on the opposite side of the third axis J3 in the second direction X, across the first axis J1. According to this embodiment, the first fluid guide 70 can be disposed apart in the second direction X from the ring gear 51, which is the gear with the largest diameter. Furthermore, by disposing the first fluid guide 70 around a gear with a diameter smaller than that of the ring gear 51 in the internal space of the gear accommodating portion 6b, the transmission mechanism 4 can be made smaller in size in the second direction X.

[0074] The first inclined portion 71 has a first plate portion 71a and a second plate portion 71b aligned in the second direction X. The first plate portion 71a is inclined at an inclination angle α with respect to the second direction X. The second plate portion 71b is inclined at an inclination angle β with respect to the second direction X. The first plate portion 71a is connected to an end portion of the second plate portion 71b on one side (-X) in the second direction.

[0075] According to this embodiment, the inclination angle α of the first inclined portion 71 with respect to the second direction X decreases as it moves from the other side (+X) in the second direction to one side (-X) in the second direction. According to this embodiment, the fluid O scooped up by the ring gear 51 is received by the second plate portion 71b, which has a large inclination angle β, and guided to the first plate portion 71a, which has a small inclination angle α, and can be supplied from the first plate portion 71a to the meshing portion 49. By increasing the inclination angle β of the second plate portion 71b, the second plate portion 71b can be brought closer to the ring gear 51 that scoops up the fluid O, allowing the second plate portion 71b to receive more of the fluid O before the range in which the fluid O scatters to expand. Furthermore, by decreasing the inclination angle α of the first plate portion 71a, the component in the second direction X of the flow velocity vector of the fluid O flowing out from the first plate portion 71a to one side (-X) in the second direction can be made larger than the component in the vertical direction Z of the flow velocity vector. This makes it easier to supply the fluid O from the first fluid guide 70 to the meshing portion 49 even if the first fluid guide 70 and the meshing portion 49 are spaced apart in the second direction X.

[0076] In the present embodiment, the first inclined portion 71 is described as having a first plate portion 71a and a second plate portion 71b with a uniform inclination angle arranged side by side in the second direction X, so that the inclination angle changes stepwise along the second direction X. However, the first inclined portion 71 may have a curved shape in which the inclination angle changes continuously along the second direction X.

[0077] The second plate portion 71b extends from the inner surface of the first surrounding portion 68 toward one side (-X) in the second direction. That is, the first fluid guide 70 is connected to the inner surface of the first surrounding portion 68. This allows the first fluid guide 70 to receive a larger amount of the fluid O that is scooped up by the ring gear 51 and scattered toward the other side (+X) in the second direction, and supply it to the meshing portion 49.

[0078] The second inclined portion 72 in this embodiment is connected to the end of the first inclined portion 71 on one side (-X) in the second direction, and is inclined upward as it moves from the other side (+X) in the second direction to one side (-X). Therefore, the first inclined portion 71 and the second inclined portion 72 are arranged in a V shape when viewed from the first direction Y. According to this embodiment, it is possible to temporarily retain the fluid O on the upper side of the first fluid guide 70, and the received fluid O can be easily flowed in the first direction Y and supplied to a desired region (the meshing portion 49 in this embodiment).

[0079] FIG. 4 is a perspective view of the first fluid guide 70 of this embodiment. 4, in the first fluid guide 70, both a first inclined portion 71 and a second inclined portion 72 are provided in the first portion 70A, and only the first inclined portion 71 is provided in the second portion 70B. Here, a portion of the first inclined portion 71 that is located on the other side (+X) in the second direction from the second inclined portion 72 and extends further toward the one side (+Y) in the first direction than the end of the second inclined portion 72 on the one side (+Y) in the first direction is referred to as an extended portion 71q. In this embodiment, the extended portion 71q is at least a part of the first inclined portion 71 provided in the second portion 70B.

[0080] The extension portion 71q overlaps with the second gear 42 in the radial direction. The second inclined portion 72 is not connected to the one side (-X) of the extension portion 71q in the second direction. Therefore, the end portion of the extension portion 71q on the one side (-X) of the second direction directly faces the second gear 42. According to this embodiment, the first inclined portion 71 has the extension portion 71q, so that the fluid O received by the first fluid guide 70 can flow out from the end portion of the extension portion 71q on the one side (-X) of the second direction to the one side (-X) of the second direction. This allows the fluid O to be supplied to the meshing portion 49 between the second gear 42 and the first gear 41, which faces the extension portion 71q.

[0081] In the present embodiment, the second inclined portion 72 is provided in the first portion 70A, and the extending portion 71q is provided in the second portion 70B. Note that it is sufficient that at least a portion of the second inclined portion 72 is provided in the first portion 70A, and at least a portion of the extending portion 71q is provided in the second portion 70B. With this configuration, the first fluid guide 70 having the second inclined portion 72 and the extending portion 71q can be easily configured by butting the first portion 70A and the second portion 70B together in the first direction Y.

[0082] In particular, in this embodiment, the entire second inclined portion 72 is provided in the first portion 70A, and the entire extending portion 71q is provided in the second portion 70B. In this case, the first portion 70A and the second portion 70B can each have a substantially uniform cross-sectional shape. According to this embodiment, the shapes of the first portion 70A and the second portion 70B can be simplified, and the manufacturing cost of the housing 6 can be reduced.

[0083] Furthermore, it is preferable that the entire second inclined portion 72 is provided in the first portion 70A, and at least a portion of the extension portion 71q is provided in the second portion 70B. In particular, when the housing 6 including the first portion 70A and the second portion 70B is manufactured by a manufacturing method using a mold, such as casting, it is preferable that the mold for the first portion 70A and the second portion 70B is drawn in the first direction Y. By providing the entire second inclined portion 72 in the first portion 70A, it is possible to prevent the distal end of the second portion 70B from being wider than the proximal end. This eliminates the need to provide a slide mechanism in the mold used to mold the second portion 70B, simplifying the mold structure.

[0084] In this embodiment, the upper surface of the first portion 70A preferably slopes downward toward one side (+Y) in the first direction. In this case, the fluid O received by the first portion 70A can flow toward the second portion 70B by utilizing gravity. This makes it easier to supply the fluid O received by the first portion 70A to the meshing portion 49 from the extension portion 71q of the second portion 70B.

[0085] If at least a portion of the upper surface of the first fluid guide 70 is inclined downward in the first direction Y as it approaches the second gear 42, the fluid O received by the first fluid guide 70 can be made to flow toward the second gear 42 by utilizing gravity. In other words, it is sufficient that at least a portion of the upper surface of the first fluid guide 70 is inclined downward in the first direction Y as it approaches the second gear 42.

[0086] 4, the first inclined portion 71 of the present embodiment radially overlaps with the second gear 42 at the extension portion 71q. According to the present embodiment, the fluid O that is received by the first fluid guide 70 and flows out from the first inclined portion 71 in the second direction X can be easily supplied to the meshing portion 49.

[0087] The first inclined portion 71 of the present embodiment overlaps with the second gear 42 in the up-down direction Z at the extension portion 71q. According to the present embodiment, it is easy to arrange the first inclined portion 71 close to the meshing portion 49 of the first gear 41 and the second gear 42, and it is easy to supply the fluid O flowing through the first inclined portion 71 to the meshing portion 49.

[0088] The second inclined portion 72 of this embodiment overlaps with the second gear 42 in the first direction Y. According to this embodiment, the first fluid guide 70 can be disposed close to the second gear 42, making it easier to supply the fluid O received by the first fluid guide 70 to the meshing portion 49. In addition, according to this embodiment, a portion of the first fluid guide 70 overlaps with the second gear 42 in the first direction Y, making it possible to reduce the size of the gear accommodating portion 6b in the second direction X.

[0089] The second inclined portion 72 of this embodiment overlaps with the ring gear 51 in the radial direction. The fluid O scooped up by the ring gear 51 is mainly scattered in the region overlapping with the ring gear 51 in the radial direction. According to this embodiment, the second inclined portion 72 blocks the fluid O scooped up by the ring gear 51 and received by the first inclined portion 71, thereby preventing the fluid O from flowing out of the first fluid guide 70 to one side in the second direction. This allows the first fluid guide 70 to direct the received fluid O to a region that does not overlap with the ring gear 51 in the radial direction, making it possible to supply the fluid O to regions that are difficult for the fluid O to reach by scooping up by the ring gear 51 alone.

[0090] As shown in FIG. 2 , the gear accommodating portion 6b is provided with a second supply pipe 94A located above the first fluid guide 70. In this embodiment, the second supply pipe 94A is a cylindrical member and extends along the first direction Y. The second supply pipe 94A is provided with at least one supply port 94h that opens toward the first fluid guide 70. The second supply pipe 94A supplies a portion of the fluid O flowing through the flow path 90 from the supply port 94h to the first fluid guide 70. According to this embodiment, the first fluid guide 70 can supply not only the fluid O scooped up by the ring gear 51 but also the fluid O discharged from the second supply pipe 94A to the meshing portion 49. That is, according to this embodiment, a larger amount of fluid O can be supplied to the meshing portion 49.

[0091] In the present embodiment, the fluid O flowing through the second supply pipe 94A is pressure-fed by the pump 8. Therefore, the fluid O can be stably supplied to the second supply pipe 94A regardless of the driving state of the motor 2. For example, when the vehicle equipped with the drive unit 100 tilts and the rotation speed of the motor 2 slows, such as when the vehicle is going uphill, the fluid O accumulated in the storage section may become uneven within the storage section, the amount of fluid O scooped up by the ring gear 51 may decrease, and the amount of fluid O supplied to the gears, the meshing portion 49, and the like may become insufficient. However, according to the present embodiment, even when the amount of fluid O scooped up by the ring gear 51 decreases and the supply of fluid O to the gears, etc. is insufficient, the fluid O can be sent to the first fluid guide 70 by flowing the fluid O through the second supply pipe 94A, and the insufficient supply of fluid O to the meshing portion 49 may be prevented.

[0092] In the present embodiment, the second supply pipe 94A is provided in the gear housing 6b as a supply unit that supplies the fluid O to the first fluid guide 70. However, the structure of the supply unit is not limited to this embodiment as long as it stores or flows the fluid O and has a supply port that supplies the fluid O to the first fluid guide 70. The supply unit may be, for example, a flow path or a storage unit provided inside the wall of the gear housing 6b. The supply unit may also be a gutter or the like that is disposed in the internal space of the gear housing 6b and stores or flows the fluid O. If the supply unit has a structure that opens at the top of a gutter or the like, the supply port may be the upper opening of the supply unit and supply overflowing fluid O to the first fluid guide 70.

[0093] As shown in FIG. 1 , the housing 6 may be provided with holes 70c and 70d that open to the upper surface of the first fluid guide 70 and penetrate the first fluid guide 70 in the vertical direction Z. The holes 70c and 70d are preferably provided at positions corresponding to areas requiring the supply of fluid O. In this embodiment, the holes 70c and 70d extend from the upper surface of the first fluid guide 70 to the support portions of the bearings B1 and B2 that support the first shaft 46. The holes 70c and 70d supply a portion of the fluid O flowing along the upper surface of the first fluid guide 70 to the bearings B1 and B2. The first fluid guide 70 may also be provided with openings of holes that supply fluid O to the other bearings B3, B4, and B7.

[0094] <Second fluid guide> As shown in FIG. 2, the second fluid guide 80 is located on one side (-X) in the second direction of the first axis J1 and the second axis J2 and on the other side (+X) in the second direction of the third axis J3. The second fluid guide 80 extends upward from the bottom of the first enclosure 68. The second fluid guide 80 extends along the first direction Y to connect the first wall 65 and the second wall 66. The second fluid guide 80 divides the reservoir P in the gear accommodating portion 6b in the second direction X. This makes it easier to maintain the liquid level in the reservoir P at a certain level or higher around the ring gear 51, allowing the ring gear 51 to stably scoop up the fluid O in the reservoir P.

[0095] The second fluid guide 80 has a third portion 80A shown in Fig. 2 and a fourth portion 80B shown in Fig. 3. The third portion 80A and the fourth portion 80B are connected and aligned in the first direction Y. The third portion 80A extends from the first wall portion 65 to one side (+Y) in the first direction. The fourth portion 80B extends from the second wall portion 66 to the other side (-Y) in the first direction.

[0096] The leading end surface of the third portion 80A facing one side in the first direction (+Y) and the leading end surface of the fourth portion 80B facing the other side in the first direction (-Y) face each other and contact each other. The leading end surfaces of the third portion 80A and the fourth fluid guide 87 may face each other via a gap. The leading end surface of the third portion 80A is disposed on the same plane as the first opposing surface 68f of the first surrounding wall 68a. Therefore, when machining the leading end surface of the third portion 80A, machining such as milling can be performed on the leading end surface of the third portion 80A and the first opposing surface 68f simultaneously. The leading end surface of the fourth portion 80B is disposed on the same plane as the second opposing surface 68g of the second surrounding wall 68b. Therefore, when machining the leading end surface of the fourth portion 80B, machining such as milling can be performed on the leading end surface of the fourth portion 80B and the second opposing surface 68g simultaneously. The tip end surface of the third portion 80A and the tip end surface of the fourth portion 80B do not necessarily have to be disposed on the same plane as the first opposing surface 68f and the second opposing surface 68g.

[0097] The second fluid guide 80 extends in a substantially arcuate shape in the circumferential direction centered on the third axis J3. In this embodiment, the second fluid guide 80 extends along the tooth tips of the ring gear 51. As a result, the fluid O scooped up by the ring gear 51 rotating in the first rotational direction R1 flows along the second fluid guide 80 and splashes onto the upper side of the second fluid guide 80. The second fluid guide 80 guides the fluid O splashing through the first path F1, the second path F2, and the third path F3.

[0098] The second fluid guide 80 has an opposing surface 80f that faces the ring gear 51 in the radial direction of the third axis J3. In this embodiment, the opposing surface 80f is a curved surface that extends in the circumferential direction about the third axis J3. The opposing surface 80f is provided with a protrusion 81 that protrudes in the radial direction of the third axis J3. Note that the opposing surface 80f may extend linearly without being curved, as long as it extends in the radial direction of the third axis J3 and faces the ring gear 51.

[0099] FIG. 5 is a perspective view showing a part of the second fluid guide 80 of this embodiment. As shown in FIG. 5, the convex portion 81 is located below the meshing portion 49 between the first gear 41 and the second gear 42 and on the other side (-Y) in the first direction. The convex portion 81 has a substantially triangular shape when viewed from the radial direction of the third axis J3. A guide surface 81f is provided on the lower surface of the convex portion 81. The guide surface 81f inclines from the other side (-Y) in the first direction to one side (+Y) as it extends upward. The shape of the second fluid guide 80 is not limited to this embodiment. For example, the guide surface 81f may be curved, and the shape of the convex portion 81 does not have to be substantially triangular.

[0100] According to the second fluid guide 80 of the present embodiment, part of the fluid O that splashes upward between the tooth tips of the ring gear 51 and the opposing surface 80f can be guided to one side (+Y) in the first direction on the guide surface 81f. This makes it possible to change the splash direction of part of the fluid O that is scooped up by the ring gear 51 to one side (+Y) in the first direction, and to supply the fluid O to an area that does not overlap with the ring gear 51 in the radial direction.

[0101] In particular, in this embodiment, the first gear 41, the second gear 42, and the third gear 43 are located on one side (+Y) in the first direction relative to the ring gear 51. That is, the meshing portion 49 is disposed on one side (+Y) in the first direction of the convex portion 81. Therefore, the second fluid guide 80 can guide the fluid O by the guide surface 81f and supply it to the meshing portion 49.

[0102] <Third fluid guide> As shown in FIG. 2, the third fluid guide 83 is located above the first axis J1, the second axis J2, and the third axis J3. The third fluid guide 83 is located on one side (-X) in the second direction of the first axis J1 and the second axis J2 and on the other side (+X) in the second direction of the third axis J3. The third fluid guide 83 extends from the first wall portion 65 to one side (+Y) in the first direction. The third fluid guide 83 overlaps with the ring gear 51 in the radial direction. At least a portion of the third fluid guide 83 is located above the ring gear 51.

[0103] FIG. 6 is a perspective view of the third fluid guide 83 and the fourth fluid guide 87. As shown in FIG. The third fluid guide 83 has a vertical wall portion 84, a first bottom wall portion 85, and a second bottom wall portion 86. The vertical wall portion 84 extends in the up-down direction Z. The first bottom wall portion 85 extends from the lower portion of the vertical wall portion 84 toward one side (-X) in the second direction. The second bottom wall portion 86 extends from the lower portion of the vertical wall portion 84 toward the other side (+X) in the second direction.

[0104] According to this embodiment, the fluid O that splashes through the third path F3 hits the surface of the vertical wall portion 84 that faces the other side (+X) in the second direction. This allows the fluid O to be guided to the upper side of the second bottom wall portion 86. Furthermore, the second bottom wall portion 86 can guide the fluid O that flows from the vertical wall portion 84 in a desired direction.

[0105] Furthermore, according to this embodiment, the fluid O splashing through the fourth path F4 hits the surface of the vertical wall portion 84 facing one side (-X) in the second direction. This allows the fluid O to be guided to the upper side of the first bottom wall portion 85. Furthermore, the first bottom wall portion 85 can guide the fluid O flowing from the vertical wall portion 84 in a desired direction. That is, the third fluid guide 83 of this embodiment can receive and guide the fluid O in a desired direction regardless of whether the fluid O passes through the third path F3 or the fourth path F4.

[0106] The first bottom wall portion 85 of this embodiment is inclined upward as it moves away from the vertical wall portion 84 in the second direction X. Therefore, the third fluid guide 83 can store the fluid O between the vertical wall portion 84 and the first bottom wall portion 85. This makes it easy for the third fluid guide 83 to direct the fluid O, which has been scooped up by the ring gear 51, in the first direction Y. Similarly, the second bottom wall portion 86 of this embodiment is inclined upward as it moves away from the vertical wall portion 84 in the second direction X. Therefore, the third fluid guide 83 can store the fluid O between the vertical wall portion 84 and the second bottom wall portion 86. This makes it easy for the third fluid guide 83 to direct the fluid O, which has been scooped up by the ring gear 51, in the first direction Y.

[0107] In this embodiment, the upper surfaces of the first bottom wall portion 85 and the second bottom wall portion 86 are inclined downward toward one side (+Y) in the first direction. Therefore, the first bottom wall portion 85 and the second bottom wall portion 86 can use gravity to cause the fluid O flowing from the vertical wall portion 84 to flow toward the one side (+Y) in the first direction. In this embodiment, a fourth fluid guide 87 is disposed on the one side (+Y) in the first direction of the third fluid guide 83. Therefore, the third fluid guide 83 guides the fluid O passing through the third path F3 or the fourth path F4 to the fourth fluid guide 87. It is sufficient that at least a portion of the upper surfaces of the first bottom wall portion 85 and the second bottom wall portion 86 are inclined downward toward the one side (+Y) in the first direction.

[0108] <Fourth fluid guide> 3, the fourth fluid guide 87 overlaps with the third fluid guide 83 in the first direction Y. That is, the fourth fluid guide 87 is arranged side by side with the third fluid guide 83 in the first direction Y. The fourth fluid guide 87 extends from the second wall portion 66 to the other side (-Y) in the first direction.

[0109] Similar to the third fluid guide 83, the fourth fluid guide 87 is located above the first axis J1, the second axis J2, and the third axis J3. The fourth fluid guide 87 is located on one side (-X) in the second direction of the first axis J1 and the second axis J2 and on the other side (+X) in the second direction of the third axis J3. The fourth fluid guide 87 overlaps with the second gear 42 in the radial direction. At least a portion of the fourth fluid guide 87 is located above the second gear 42.

[0110] The fourth fluid guide 87 extends in the circumferential direction of the third axis J3. The upper surface of the fourth fluid guide 87 is located lower than the upper surfaces of the first bottom wall portion 85 and the second bottom wall portion 86. Therefore, the fluid O flowing from the third fluid guide 83 to one side (+Y) in the first direction is supplied to the upper surface of the fourth fluid guide 87.

[0111] In this embodiment, the upper surface of the fourth fluid guide 87 is inclined downward as it approaches the other side (+X) in the second direction. That is, the upper surface of the fourth fluid guide 87 is inclined downward in the second direction X as it approaches the second gear 42. Therefore, the fourth fluid guide 87 can supply the fluid O guided from the third fluid guide 83 to the tooth surface of the second gear 42. It is sufficient that at least a portion of the upper surface of the fourth fluid guide 87 is inclined downward as it approaches the other side (+X) in the second direction.

[0112] According to the present embodiment, at least a portion of the upper surface of the fourth fluid guide 87 is located below the upper surface of the third fluid guide 83. Therefore, the fluid O flowing along the upper surface of the third fluid guide 83 can be supplied to the upper surface of the fourth fluid guide 87. Furthermore, the fourth fluid guide 87 guides the fluid O guided from the third fluid guide 83 in a desired direction, so that the fluid O passing through the third path F3 or the fourth path F4 can be used to lubricate gears, bearings, etc.

[0113] The leading end surface of the third fluid guide 83 facing one side in the first direction (+Y) and the leading end surface of the fourth fluid guide 87 facing the other side in the first direction (-Y) face each other and contact each other. The leading end surfaces of the third fluid guide 83 and the fourth fluid guide 87 may face each other via a gap. In the axial direction, the leading end surface of the third fluid guide 83 is located on the same plane as the first opposing surface 68f of the first surrounding wall 68a. Therefore, when machining the leading end surface of the third fluid guide 83, the leading end surface of the third fluid guide 83 can be machined by milling or the like simultaneously with the first opposing surface 68f. In the axial direction, the leading end surface of the fourth fluid guide 87 is located on the same plane as the second opposing surface 68g of the second surrounding wall 68b. Therefore, when machining the leading end surface of the fourth fluid guide 87, the leading end surface of the fourth fluid guide 87 can be machined by milling or the like simultaneously with the second opposing surface 68g. The tip end surface of the third fluid guide 83 and the tip end surface of the fourth fluid guide 87 do not necessarily have to be disposed on the same plane as the first opposing surface 68f and the second opposing surface 68g.

[0114] In this embodiment, the first bottom wall portion 85 and the second bottom wall portion 86 of the third fluid guide 83 are inclined downward in the first direction Y as they approach the second gear 42. Therefore, the third fluid guide 83 can use gravity to cause the fluid O to flow toward the second gear 42. Similarly, the fourth fluid guide 87 is preferably inclined downward in the first direction Y as it approaches the second gear 42. In this case, the fluid O on the upper surface of the fourth fluid guide 87 can be caused to flow toward the second gear 42. That is, in this embodiment, it is preferable that the upper surface of at least one of the third fluid guide 83 and the fourth fluid guide 87 be inclined downward in the first direction Y as it approaches the second gear. Furthermore, it is sufficient that at least a portion of the upper surface of the third fluid guide 83 and the upper surface of the fourth fluid guide 87 are inclined in the above-mentioned direction.

[0115] The lower surface of the vertical wall portion 84, the first bottom wall portion 85, or the second bottom wall portion 86 of the third fluid guide 83, or the lower surface of the fourth fluid guide 87 may be inclined downward in the first direction Y as it approaches the second gear 42. In this case, the fluid O is supplied to the second gear 42 along the lower surface.

[0116] The surface of the vertical wall portion 84 facing one side (-X) in the second direction receives the fluid O flowing through the fourth path F4. The surface of the vertical wall portion 84 facing one side (-X) in the second direction may be inclined from one side (-X) in the second direction to the other side (+X) as it moves from the other side (-Y) in the first direction to the one side (+Y). In this case, part of the fluid O that flows through the fourth path F4 and hits the vertical wall portion 84 is guided to the second gear 42.

[0117] <Modification> Modifications that can be adopted in the above-described embodiment will be described below. In the description of each modification below, the same components as those in the already described embodiment or modification will be assigned the same reference numerals, and the description thereof will be omitted.

[0118] (Variation 1) 7 is a perspective view of a first fluid guide 170 of Modification 1 that can be used in the above-described embodiment. The first fluid guide 170 of this modification extends from the first wall portion 65 to one side in the first direction (+Y). In other words, the first fluid guide 170 of this modification is not divided in the first direction Y.

[0119] According to this modification, the first fluid guide 170 is made of a single member and does not have boundaries between the members. Therefore, with the first fluid guide 170 of this modification, gaps do not occur at the boundaries between the members, compared to when multiple members are connected, and the fluid O can be smoothly guided in the first direction Y.

[0120] Although this modification illustrates the case where the first fluid guide 170 extends in the first direction Y from the first wall portion 65, the first fluid guide 170 may extend in the first direction Y from the second wall portion 66. In other words, it is sufficient that the first fluid guide 170 extends in the first direction Y from either the first wall portion 65 or the second wall portion 66.

[0121] (Variation 2) 8 is a perspective view of a fourth fluid guide 287 of Modification 2 that can be used in the above-described embodiment. The fourth fluid guide 287 of this modification is located below the third fluid guide 83. That is, the fourth fluid guide 287 overlaps with the third fluid guide 83 in the up-down direction Z, and is located below the third fluid guide 83.

[0122] Similar to the above-described embodiment, the fourth fluid guide 287 extends in the first direction Y. The fourth fluid guide 287 overlaps with the second gear 42 in the radial direction. The fourth fluid guide 287 is located above the second axis J2.

[0123] According to this modification, the fourth fluid guide 287 is positioned below the third fluid guide 83. Therefore, the fourth fluid guide 287 can receive the fluid O flowing out from the third fluid guide 83. Furthermore, the fourth fluid guide 287 can guide the fluid O flowing out from the third fluid guide 83 in a desired direction, allowing the fluid O to be used for lubricating gears, bearings, etc.

[0124] The fourth fluid guide 287 of this modified example is located below the end portion on one side (+Y) in the first direction of the third fluid guide 83. Therefore, the fourth fluid guide 287 can receive the fluid O that flows out from the end portion on one side (+Y) in the first direction of the third fluid guide 83 to the one side (+Y) in the first direction.

[0125] While various embodiments and modifications of the present invention have been described above, the configurations and combinations thereof in each embodiment and modification are merely examples, and additions, omissions, substitutions, and other modifications of the configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments.

[0126] In the above-described embodiment, the arrangement and orientation of each part represented by one side and the other side in the first direction are merely examples, and may be reversed from the description in the embodiment. For example, in the above-described embodiment, the third gear and the ring gear are described as being arranged closer to the motor than the first gear and the second gear in the first direction. However, the third gear and the ring gear may be arranged farther from the motor than the first gear and the second gear in the first direction.

[0127] The configuration of each shaft of the transmission mechanism in the above-described embodiment is an example. For example, the number of shafts and gears constituting the transmission mechanism are not limited to those in the embodiment. Furthermore, the direction relative to the forward direction of the vehicle may be opposite to that in the above-described embodiment in the second direction. Furthermore, the first fluid guide, the second fluid guide, the third fluid guide, and the fourth fluid guide may be separate from the housing.

[0128] Further structures may be added to the above-described embodiment. For example, as shown in FIG. 3, the gear accommodating portion 6b may have a reservoir guide 366c located below the second gear 42. The reservoir guide 366c extends in an arc in the circumferential direction centered on the second axis J2. The fluid O is stored above the reservoir guide 366c, allowing the fluid O to be supplied to the tips of the teeth of the second gear 42.

[0129] The fluid O stored in the housing 6 is not particularly limited and may be a fluid other than oil. The fluid supplied to the motor by the fluid supply unit may be, for example, water.

[0130] The present technology can be configured as follows. [1] A transmission mechanism that transmits the power of a motor, A power transmission unit; a housing having a gear accommodating portion that accommodates the power transmission portion, a direction perpendicular to the up-down direction is defined as a first direction, and a direction perpendicular to the up-down direction and the first direction is defined as a second direction; The power transmission unit is a first gear that rotates about a first axis extending in the first direction; a second gear that meshes with the first gear and rotates about a second axis that extends parallel to the first axis; a third gear that rotates about the second axis; a fourth gear that meshes with the third gear and rotates about a third axis that extends parallel to the first axis, the third axis is located on one side in the second direction relative to the first axis, a first fluid guide extending in the first direction is provided on an inner surface of the gear accommodating portion; At least a portion of the first fluid guide the first gear is positioned above an engagement portion between the first gear and the second gear and on the other side in the second direction relative to the first axis, and overlaps with the fourth gear in the radial direction; The first fluid guide has a first inclined portion that inclines downward as it moves from the other side to the one side in the second direction. [2] The transmission mechanism according to [1], wherein the first inclined portion overlaps with the second gear in the vertical direction. [3] The transmission mechanism according to [1] or [2], wherein the first inclined portion overlaps with the second gear in the radial direction. [4] The transmission mechanism according to any one of [1] to [3], wherein the inclination angle of the first inclined portion with respect to the second direction decreases from the other side to one side in the second direction. [5] The first fluid guide has a second inclined portion connected to at least a part of an end portion of the first inclined portion on one side in the second direction, The transmission mechanism according to any one of [1] to [4], wherein the second inclined portion is inclined upward from the other side to the one side in the second direction. [6] The first inclined portion is located on the other side in the second direction than the second inclined portion and has an extending portion that extends further toward the one side in the first direction than an end portion of the second inclined portion on the one side in the first direction, The transmission mechanism according to [5], wherein the extension portion overlaps with the second gear in the radial direction. [7] The transmission mechanism described in [6], wherein the second inclined portion overlaps with the second gear in the first direction. [8] The gear accommodating portion is a first wall portion that covers the power transmission portion from the other side in the first direction; a second wall portion that covers the power transmission portion from one side in the first direction, The first fluid guide is a first portion extending from the first wall portion to one side in the first direction; a second portion extending from the second wall portion to the other side in the first direction and connected to the first portion, the second inclined portion is provided on the first portion, The transmission mechanism according to [6] or [7], wherein the extension portion is provided in the second portion. [9] The gear accommodating portion is a first wall portion that covers the power transmission portion from the other side in the first direction; a second wall portion that covers the power transmission portion from one side in the first direction, The transmission mechanism according to [6] or [7], wherein the first fluid guide extends in the first direction from either the first wall portion or the second wall portion.

[10] A transmission mechanism described in [8] or [9], wherein at least a portion of the upper surface of the first fluid guide is inclined downward as it approaches the second gear in the first direction.

[11] The first gear and the second gear are located on one side in the first direction relative to the third gear and the fourth gear, A second fluid guide is provided on the inner surface of the gear accommodating portion, the second fluid guide extends along the tooth tip of the fourth gear, a convex portion that protrudes in the radial direction is provided on a surface of the second fluid guide that faces the fourth gear in the radial direction, The transmission mechanism according to any one of [1] to

[10] , wherein a guide surface is provided on the lower surface of the convex portion, the guide surface inclining from the other side to one side in the first direction as it goes upward.

[12] The gear accommodating portion is provided with a supply portion located above the first fluid guide, The transmission mechanism according to any one of [1] to

[11] , wherein the supply unit is provided with a supply port that opens toward the first fluid guide.

[13] A third fluid guide is provided on an inner surface of the gear accommodating portion, the third fluid guide extending in the first direction and having at least a portion located above the fourth gear, The third fluid guide is a vertical wall portion extending in the up-down direction; a first bottom wall portion extending from a lower portion of the vertical wall portion toward one side in the second direction; The transmission mechanism according to any one of [1] to

[12] , further comprising: a second bottom wall portion extending from a lower portion of the vertical wall portion toward the other side in the second direction.

[14] A fourth fluid guide is provided on an inner surface of the gear accommodating portion, the fourth fluid guide being arranged alongside the third fluid guide in the first direction, overlapping the second gear in the radial direction, and positioned above the second axis; The transmission mechanism according to

[13] , wherein an upper surface of the fourth fluid guide is located lower than an upper surface of the third fluid guide.

[15] A transmission mechanism as described in

[13] , wherein a fourth fluid guide is provided on the inner surface of the gear accommodating portion, radially overlapping with the second gear, and positioned below the third fluid guide and above the second axis.

[16] A transmission mechanism described in

[14] or

[15] , wherein the upper surface of at least one of the third fluid guide and the fourth fluid guide slopes downward in the first direction as it approaches the second gear.

[17] [1] The transmission mechanism described in [1]; a drive device comprising the motor. [Explanation of symbols]

[0131] 2...motor, 3...power transmission portion, 4...transmission mechanism, 6...housing, 6b...gear accommodating portion, 41...gear, 41...first gear, 42...second gear, 43...third gear, 49...meshing portion, 51...ring gear (fourth gear), 65...first wall portion, 66...second wall portion, 70, 170...first fluid guide, 70A...first portion, 70B...second portion, 71...first inclined portion, 71p...end portion, 71q...extension portion, 72...second Inclined portion, 80...second fluid guide, 81...convex portion, 81f...guide surface, 83...third fluid guide, 84...vertical wall portion, 85...first bottom wall portion, 86...second bottom wall portion, 87, 287...fourth fluid guide, 94h...supply port, 94A...second supply pipe (supply portion), 100...drive device, J1...first axis, J2...second axis, J3...third axis, O...fluid, X...second direction, Y...first direction, Z...vertical direction, α, β...inclination angle

Claims

1. A transmission mechanism that transmits power from a motor, A power transmission unit; a housing having a gear accommodating portion that accommodates the power transmission portion, a direction perpendicular to the up-down direction is defined as a first direction, and a direction perpendicular to the up-down direction and the first direction is defined as a second direction; The power transmission unit is a first gear that rotates about a first axis extending in the first direction; a second gear that meshes with the first gear and rotates about a second axis that extends parallel to the first axis; a third gear that rotates about the second axis; a fourth gear that meshes with the third gear and rotates about a third axis that extends parallel to the first axis, the third axis is located on one side in the second direction with respect to the first axis, a first fluid guide extending in the first direction is provided on an inner surface of the gear accommodating portion; At least a portion of the first fluid guide the first gear is positioned above an engagement portion between the first gear and the second gear and on the other side in the second direction relative to the first axis, and overlaps with the fourth gear in the radial direction; the first fluid guide has a first inclined portion that is inclined downward from the other side to the one side in the second direction; Transmission mechanism.

2. The first inclined portion overlaps with the second gear in the vertical direction. The transmission mechanism according to claim 1 .

3. The first inclined portion overlaps with the second gear in the radial direction. The transmission mechanism according to claim 1 .

4. an inclination angle of the first inclined portion with respect to the second direction becomes smaller from the other side to the one side in the second direction; The transmission mechanism according to claim 1 .

5. the first fluid guide has a second inclined portion connected to at least a part of an end portion of the first inclined portion on one side in the second direction, the second inclined portion inclines upward from the other side to the one side in the second direction; The transmission mechanism according to claim 1 .

6. the first inclined portion is located on the other side in the second direction than the second inclined portion and has an extending portion that extends further toward the one side in the first direction than an end portion of the second inclined portion on the one side in the first direction, The extension portion overlaps with the second gear in the radial direction. The transmission mechanism according to claim 5 .

7. the second inclined portion overlaps with the second gear in the first direction; The transmission mechanism according to claim 6.

8. The gear accommodating portion is a first wall portion that covers the power transmission portion from the other side in the first direction; a second wall portion that covers the power transmission portion from one side in the first direction, The first fluid guide is a first portion extending from the first wall portion to one side in the first direction; a second portion extending from the second wall portion to the other side in the first direction and connected to the first portion, the second inclined portion is provided on the first portion, The extension portion is provided in the second portion. The transmission mechanism according to claim 6.

9. The gear accommodating portion is a first wall portion that covers the power transmission portion from the other side in the first direction; a second wall portion that covers the power transmission portion from one side in the first direction, The first fluid guide extends in the first direction from either the first wall portion or the second wall portion. The transmission mechanism according to claim 6.

10. At least a portion of an upper surface of the first fluid guide is inclined downward as it approaches the second gear in the first direction.

10. A transmission mechanism according to claim 8 or 9.

11. the first gear and the second gear are located on one side in the first direction relative to the third gear and the fourth gear, A second fluid guide is provided on an inner surface of the gear accommodating portion, the second fluid guide extends along a tooth tip of the fourth gear, a convex portion that protrudes in the radial direction is provided on a surface of the second fluid guide that faces the fourth gear in the radial direction, a guide surface that slopes upward from the other side to the one side in the first direction is provided on the lower surface of the convex portion; The transmission mechanism according to claim 1 .

12. The gear accommodating portion is provided with a supply portion located above the first fluid guide, The supply unit is provided with a supply port that opens toward the first fluid guide. The transmission mechanism according to claim 1 .

13. a third fluid guide extending in the first direction and at least a portion of which is located above the fourth gear is provided on an inner surface of the gear accommodating portion; The third fluid guide is a vertical wall portion extending in the up-down direction; a first bottom wall portion extending from a lower portion of the vertical wall portion toward one side in the second direction; a second bottom wall portion extending from a lower portion of the vertical wall portion toward the other side in the second direction, The transmission mechanism according to claim 1 .

14. a fourth fluid guide is provided on an inner surface of the gear accommodating portion, the fourth fluid guide being arranged alongside the third fluid guide in the first direction, overlapping with the second gear in the radial direction, and positioned above the second axis; An upper surface of the fourth fluid guide is located lower than an upper surface of the third fluid guide.

14. A transmission mechanism according to claim 13.

15. a fourth fluid guide is provided on an inner surface of the gear accommodating portion, the fourth fluid guide being radially overlapping with the second gear and positioned below the third fluid guide and above the second axis; 14. A transmission mechanism according to claim 13.

16. an upper surface of at least one of the third fluid guide and the fourth fluid guide inclines downward in the first direction as it approaches the second gear; 16. A transmission mechanism according to claim 14 or 15.

17. The transmission mechanism according to claim 1; The motor. Drive unit.

Images