Vehicle drive device

Abstract

To downsize a vehicle drive device while securing oil to appropriately lubricate a rotary member of the vehicle drive device.SOLUTION: A rotation electrical machine, a gear mechanism and an output member are coaxially arranged, and outside a case 9 storing the rotation electrical machine and the gear mechanism, an oil storage member 5 is mounted in which an oil storage part 50 is formed. The oil storage part 50 is communicated with the inside of the case 9 via a communication part provided in the case 9. The communication part includes a first communication port 93, and a second communication port arranged on an upper side Z1 further than the first communication port 93, where oil is distributed between the inside of the case 9 and the oil storage part 50.SELECTED DRAWING: Figure 5

Description

[Technical field]

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

[0002] International Publication No. 2019-073821 discloses a vehicle drive device (100) in which a vehicle drive mechanism including a rotating electric machine (2) is coaxially arranged (reference numerals in parentheses in the Background Art are those of the referenced document). Oil (7) for lubricating the drive mechanism is stored inside a case (1) of the vehicle drive device (100). This vehicle drive device (100) is configured to suppress rotational resistance by lowering the oil level below the inner diameter of a stator (24) of an inner rotor type rotating electric machine (2), thereby making it difficult for dragging of the oil (7) due to rotation of the rotor (24) and the like and stirring of the oil (7) to occur. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019-073821 Summary of the Invention [Problem to be solved by the invention]

[0004] In a configuration in which the drive mechanism is arranged on a coaxial line, excess space is less likely to be generated inside the case compared to a configuration in which the drive mechanism is arranged separately on multiple shafts. For this reason, if sufficient oil is reserved for lubrication, some of the gears included in the drive mechanism will often be submerged in oil. If the case is configured so that the space below the drive mechanism in the case is wider, it is possible to ensure the amount of oil while preventing the drive mechanism from being submerged in oil, but the case will become larger, and the vehicle drive device will also become larger.

[0005] In view of the above background, it is desirable to configure a vehicle drive device in a compact size while ensuring oil capable of properly lubricating the rotating members of the vehicle drive device. [Means for solving the problem]

[0006] In view of the above, a vehicle drive device is a vehicle drive device comprising a rotating electric machine having a rotor, an output member arranged coaxially with the rotating electric machine and drivingly connected to a wheel, a gear mechanism that transmits driving force between the rotating electric machine and the output member, and a case that houses the rotating electric machine and the gear mechanism, and further comprising an oil storage member attached to the outside of the case and having an oil storage portion formed therein, the oil storage portion being connected to the interior of the case via a communication portion provided in the case, the communication portion having a first communication port and a second communication port arranged above the first communication port, and configured to allow oil to flow between the interior of the case and the oil storage portion.

[0007] In a configuration in which the rotating electric machine and the output member are arranged on the same axis, there is often less excess space in the case than in a configuration in which the rotating electric machine and the output member are arranged on different axes. Therefore, in order to form an oil storage section that secures a sufficient amount of oil in the lower part of the case while suppressing the oil stirring resistance caused by the gear mechanism and the rotating electric machine, it is necessary to make the case shape such that the space below the gear mechanism and the rotating electric machine is secured widely, and the case is likely to become large. According to this configuration, by providing an oil storage member attached to the outside of the case, it is possible to store oil in the oil storage section formed on the outside of the case using the oil storage member. Therefore, it is possible to suppress the amount of oil inside the case to be small while securing the amount of oil required for the vehicle drive device. Therefore, it is easy to suppress the oil stirring resistance caused by the gear mechanism and the rotating electric machine housed in the case to be small, and it is easy to achieve a miniaturization of the case. In other words, according to this configuration, it is possible to configure the vehicle drive device to be small while securing oil that can properly lubricate the rotating members of the vehicle drive device.

[0008] Further features and advantages of the drive device for a vehicle will become apparent from the following description of an exemplary and non-limiting embodiment, which is given with reference to the drawings. [Brief description of the drawings]

[0009] [Figure 1] Schematic external perspective view of a vehicle drive device [Diagram 2] Schematic skeleton diagram of a vehicle drive device [Diagram 3] Schematic exploded perspective view of a vehicle drive device [Figure 4] FIG. 1 is a front view of a vehicle drive device as viewed from a first axial side; [Diagram 5] A side view and a partially enlarged cross-sectional view of a vehicle drive device [Figure 6] FIG. 1 is a diagram showing an example of an oil passage through which oil discharged from an oil pump flows. [Figure 7] Schematic external perspective view of an oil storage member DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of a vehicle drive device will be described with reference to the drawings. As shown in Fig. 1 to Fig. 3, the vehicle drive device 100 is a single-shaft drive device including a rotating electric machine 1 having a rotor 11 arranged on a rotating shaft X, an output member (differential side gear 31, drive shaft DS) arranged on the rotating shaft X coaxial with the rotating electric machine 1 and drivingly connected to wheels W, a gear mechanism 4 that transmits driving force between the rotating electric machine 1 and the output member, and a case 9 that accommodates the rotating electric machine 1 and the gear mechanism 4. As will be described in detail later with reference to Fig. 2, in this embodiment, the gear mechanism 4 includes a planetary gear mechanism 2 that functions as a reducer and a differential gear device 3 that distributes the rotation transmitted from the rotating electric machine 1 to a pair of wheels W. As will be described in detail later, the vehicle drive device 100 further includes an oil storage member 5 that is attached to the outside of the case 9 and has an oil storage portion 50 formed therein.

[0011] In addition, when the vehicle drive device 100 is mounted on the vehicle in a standard posture (mounted on the vehicle or standard mounted on the vehicle), the direction along the vertical direction is referred to as the "upper-lower direction Z", the upper side in the vertical direction Z is referred to as the "upper side Z1", and the lower side is referred to as the "lower side Z2". In addition, the direction along the rotation axis X is referred to as the "axial direction L", one side in the axial direction L is referred to as the "first axial side L1", and the other side is referred to as the "second axial side L2". In addition, in this specification, with regard to the arrangement of two elements, "overlapping when viewed from a specific direction" means that when a virtual line parallel to the line of sight is moved in each direction perpendicular to the virtual line, there is at least a part of an area where the virtual line intersects both of the two elements.

[0012] 4 and 5, the oil reservoir 50 communicates with the inside of the case 9 (at least a first storage chamber E1 described below) via communication parts (first communication port 93, second communication port 94) provided in the case 9. The communication parts include the first communication port 93 and the second communication port 94 that is disposed on the upper side Z1 of the first communication port 93, and are configured to allow oil to circulate between the inside of the case 9 and the oil reservoir 50.

[0013] As shown in FIG. 2, the rotating electric machine 1 is an inner rotor type rotating electric machine including a stator 12 fixed to a case 9 and a rotor 11 arranged radially inside the stator 12. The stator 12 includes a stator core 12a and a stator coil 12b wound around the stator core 12a. The rotor 11 is connected to a rotor shaft 13 arranged radially inside the rotor 11, and the rotor 11 and the rotor shaft 13 rotate integrally. In this embodiment, the rotor shaft 13 is a hollow cylindrical member, and a drive shaft DS (which may be a connecting member as described later) penetrates the rotor shaft 13 radially inside. The rotor shaft 13, the rotor 11, and the drive shaft DS are arranged on a rotation axis X. For example, a sun gear of the planetary gear mechanism 2 is formed integrally with the rotor shaft 13. The sun gear may be formed integrally with the rotor shaft 13 by the same member, or may be formed by a separate member and connected by welding or the like.

[0014] Although detailed structure is omitted since it is a known configuration, the planetary gear mechanism 2 includes, for example, a sun gear, a ring gear, a plurality of pinion gears arranged between the sun gear and the ring gear, and a carrier that rotatably supports the plurality of pinion gears. For example, in the case where the sun gear that rotates integrally with the rotor shaft 13 as described above is the input element, the ring gear can be fixed to the case 9 and the carrier can be used as the output element to configure the planetary gear mechanism 2 as a reducer. Note that the planetary gear mechanism 2 can be of various configurations, such as a so-called single pinion type or double pinion type.

[0015] The differential gear device 3 includes a differential gear mechanism that distributes the power transmitted from the output element of the planetary gear mechanism 2 to a pair of wheels W, and a differential input gear that inputs the power from the planetary gear mechanism 2 to the differential gear mechanism. Although a detailed structure is omitted because it is a known configuration, the differential gear mechanism is configured, for example, by a bevel gear mechanism including a plurality of differential pinion gears and a pair of differential side gears 31 that mesh with the plurality of differential pinion gears. The differential pinion gears are supported rotatably by pinion shafts that are supported by the differential case and arranged to extend along the radial direction. The pinion shafts rotate integrally with the differential case, and the differential pinion gears are configured to rotate freely about the pinion shafts and revolve freely about the rotation axis X of the differential case. The plurality of pinion shafts are arranged radially (for example, in a cross shape) about the rotation axis X of the differential case, and a differential pinion gear is attached to each of the plurality of pinion shafts. The differential case accommodates the pinion gear, the differential side gear 31, and the pinion shaft inside. The differential case rotates integrally with the differential input gear.

[0016] The differential side gears 31 are arranged in a pair on the axial first side L1 and the axial second side L2 at a distance from each other. Each of the pair of differential side gears 31 is arranged to mesh with each of the multiple differential pinion gears and rotate around the rotation axis of the differential case. As shown in FIG. 2, the differential side gear 31 on the axial first side L1 is connected to the drive shaft DS on the axial first side L1 and is drivingly connected to the wheels W on the axial first side L1. The differential side gear 31 on the axial second side L2 is connected to the drive shaft DS on the axial second side L2 and is drivingly connected to the wheels W on the axial second side L2. Since the differential gear device 3 is arranged on the axial first side L1 with respect to the rotating electric machine 1, the drive shaft DS on the axial second side L2 penetrates the radial inner side of the hollow cylindrical rotor shaft 13 and extends further toward the axial second side L2 than the rotating electric machine 1. The drive shaft DS on the second axial side L2 may be composed of a member (a so-called drive shaft) that is drivingly connected to the wheels W, and a connecting member that is connected to the differential side gear 31 and connects the member (drive shaft DS) to the differential side gear 31. The differential side gear 31 and the drive shaft DS correspond to an output member in the vehicle drive device 100.

[0017] As shown in FIG. 3, the case 9 is formed with a first housing chamber E1 in which the gear mechanism 4 is housed, a second housing chamber E2 in which the rotating electric machine 1 is housed, and a third housing chamber E3 in which the rotating electric machine control device 10 that drives and controls the rotating electric machine 1 is housed. In this embodiment, the case 9 includes a first case member 91, a second case member 92, and a cover member 95. The first case member 91 is formed in a bottomed cylindrical shape centered on the rotation axis X so as to surround a space that becomes the first housing chamber E1 in which the gear mechanism 4 is mainly housed. The second case member 92 includes a cylindrical portion formed in a bottomed cylindrical shape centered on the rotation axis X so as to surround a space that becomes the second housing chamber E2 in which the rotating electric machine 1 is mainly housed, and a box-shaped portion formed in a bottomed rectangular cylindrical shape centered in the direction along the vertical direction Z so as to surround a space that becomes the third housing chamber E3 in which the rotating electric machine control device 10 is housed. The second case member 92 is partitioned by a partition wall, with a cylindrical portion forming the second storage chamber E2 being arranged below the partition wall Z2, and a box-shaped portion forming the third storage chamber E3 being arranged above the partition wall Z1.

[0018] An end face of the second axial side L2 of the first case member 91 and an end face of the first axial side L1 of the cylindrical portion of the second case member 92 are joined, and an end of an upper side Z1 of a wall portion forming an opening of the box-shaped portion of the second case member 92 is joined to a cover member 95, thereby forming a case 9 having a first storage chamber E1, a second storage chamber E2, and a third storage chamber E3 therein. In this embodiment, a partition portion 99 extending in the up-down direction Z is formed between the first storage chamber E1 and the second storage chamber E2 (see FIG. 5).

[0019] The rotating electric machine 1 is driven and controlled by a rotating electric machine control device 10 based on a target torque of the rotating electric machine 1 that is set according to a command from a vehicle control device (not shown). The rotating electric machine 1 is a multi-phase (e.g., three-phase) AC rotating electric machine, and is driven by electric power supplied from a DC power source (high-voltage DC power source with a rated voltage of about 200 to 800 volts) (not shown) mounted on the vehicle. The DC power source is a power storage device such as a rechargeable secondary battery such as a lithium-ion battery or an electric double-layer capacitor, and the rotating electric machine 1 has a function as a motor (electric motor) that receives power from the DC power source to generate power, and a function as a generator (electric generator) that receives power from the wheel W side to generate power.

[0020] The rotating electric machine control device 10 controls the switching of an inverter composed of a plurality of switching elements, and causes the inverter to convert power between DC and multiple-phase AC. The switching elements are power semiconductor elements, for example, IGBTs (Insulated Gate Bipolar Transistors) and power MOSFETs (Metal Oxide Semiconductor Field Effect Transistors). The rotating electric machine control device 10 is configured to include an ECU (Electronic Control Unit) composed of a processor such as a microcomputer as its core, an inverter, a drive circuit connecting the ECU and the inverter, and the like. The rotating electric machine control device 10 may further include a DC link capacitor connected to the DC side of the inverter to smooth the DC voltage.

[0021] In the case 9, oil is also stored for cooling the stator coil 12b, lubricating the bearings that rotatably support the rotor shaft 13, lubricating each gear and bearing constituting the planetary gear mechanism 2, lubricating each gear and bearing constituting the differential gear device 3, and lubricating the bearings that rotatably support the drive shaft DS. In the vehicle drive device 100 having a single shaft configuration in which the rotating electric machine 1, the gear mechanism 4, the drive shaft DS, and the wheels W are coaxially arranged as in the present embodiment, the excess space in the case is smaller than that in a vehicle drive device having two or more shafts. For this reason, in order to secure a sufficient amount of oil in the lower part of the case 9 while suppressing the oil stirring resistance caused by the gear mechanism 4 and the rotor 11 to a small amount, it is necessary to shape the case 9 so as to secure a larger space on the lower side Z2 than the gear mechanism 4 and the rotating electric machine 1, and the case 9 is likely to be large in size. In this embodiment, by providing an oil storage member 5 attached to the outside of the case 9, it is possible to prevent the case 9, which is made of metal, from becoming larger, while storing oil in an oil storage section 50 formed on the outside of the case 9 using an oil storage member 5 formed, for example by resin molding, which is lighter and less expensive than metal.

[0022] As shown in FIG. 3 and FIG. 7, the oil storage member 5 includes a lower surface facing portion 5a arranged to face the lower surface 9b of the case 9, a side surface facing portion 5c arranged to face the side surface 9c of the case 9, and an axial facing portion 5d arranged to overlap the case 9 and face the case 9 when viewed in the axial direction L. The lower surface 9b of the case 9 refers to the outer surface of the case 9 located on the lower side Z2 of the horizontal direction when mounted on the vehicle, and preferably refers to the outer surface of the case 9 located on the lower side Z2 of the horizontal direction and included within a range of 90 degrees around the vertical direction Z. The side surface 9c of the case 9 refers to the outer surface of the case 9 included within a range of 45 degrees to the upper side Z1 and the lower side Z2, respectively, based on the horizontal direction. Note that the lower surface 9b of the case 9 and the side surface 9c of the case 9 may partially overlap with each other on the outer surface of the case 9.

[0023] 1, 4, 5, etc., when the lower surface facing portion 5a of the oil storage member 5 is arranged to overlap either the gear mechanism 4 or the rotating electric machine 1, whichever has a smaller outer diameter, when viewed in the vertical direction Z, the oil storage portion 50 can be formed on the outside of the case 9 while suppressing an increase in the overall diameter of the vehicle drive device 100. Note that it is sufficient that the lower surface facing portion 5a of the oil storage member 5 overlaps at least a part of the gear mechanism 4 when viewed in the vertical direction Z.

[0024] Naturally, the oil reservoir member 5 may be disposed such that the lower surface facing portion 5a overlaps with either the gear mechanism 4 or the rotating electric machine 1, whichever has a larger outer diameter, when viewed in the vertical direction Z. In this case as well, the expansion of the case 9 is suppressed compared to a configuration in which the capacity of the oil reservoir 50 is expanded inside the case 9.

[0025] 1, 4, 5, etc., in this embodiment, the first communication port 93 is provided in an area of ​​the case 9 facing the axially opposed portion 5d, and is configured to communicate between a lower area E9 inside the case 9 and the oil reservoir 50. The second communication port 94 is provided in an area of ​​the case 9 facing the side face opposed portion 5c, and is configured to allow oil scooped up by a rotating body (for example, a differential case or differential input gear of the differential gear unit 3, or a carrier of the planetary gear mechanism 2) that rotates in conjunction with the rotor 11 to flow into the oil reservoir 50.

[0026] Since the oil scooped up by the gears of the planetary gear mechanism 2 and the differential gear device 3 can flow into the oil reservoir 50 from the second communication port 94, the amount of oil in the case 9 can be reduced while the vehicle is running with the gears rotating, and the oil stirring resistance caused by the rotating bodies such as the gears can be reduced. Inside the case 9, the oil used for cooling and lubrication falls into the lower area E9 of the case 9, but since the lower area E9 and the oil reservoir 50 are connected via the first communication port 93, the circulation of oil between the inside of the case 9 and the oil reservoir 50 can be ensured. Therefore, for example, the oil used for cooling and lubrication can be collected and appropriately used for the next cooling and lubrication.

[0027] In this embodiment, the lower surface facing portion 5a of the oil storage member 5 is arranged to overlap either the gear mechanism 4 or the rotating electric machine 1, whichever has a smaller outer diameter, as viewed in the vertical direction Z, and the oil storage member 5 is arranged on the lower side Z2 of the first case member 91. Therefore, the second case member 92, which houses either the gear mechanism 4 or the rotating electric machine 1, whichever has a larger outer diameter, overlaps with the oil storage member 5 as viewed in the axial direction L, and the oil storage member 5 has an axial facing portion 5d facing the second case member 92. In order to ensure smooth flow of oil between the inside of the case 9 and the oil storage portion 50, it is preferable that the first communication port 93 is provided below the lower region E9 in the case 9 so as to communicate with the oil storage portion 50. Therefore, it is preferable that the first communication port 93 is provided in a region of the case 9 that faces the axial facing portion 5d.

[0028] Here, consider a case where the lower surface facing portion 5a of the oil storage member 5 is arranged to overlap with either the gear mechanism 4 or the rotating electric machine 1, whichever has a larger outer diameter, as viewed in the vertical direction Z. For example, when applied to the case 9 of this embodiment, this corresponds to a case where the oil storage member 5 is arranged on the lower side Z2 of the second case member 92. In this case, the oil storage member 5 does not overlap with the first case member 91 as viewed in the axial direction L, and the oil storage member 5 does not have an axial facing portion 5d facing the first case member 91. Therefore, in this case, it is preferable that the first communication port 93 communicating with the oil storage portion 50 below the lower region E9 of the case 9 is provided in the area of ​​the case 9 facing the lower surface facing portion 5a.

[0029] That is, the first communication port 93 is preferably provided in an area of ​​the case 9 facing the axial facing portion 5d or the underside facing portion 5a, and is configured to connect the lower area E9 inside the case 9 with the oil storage portion 50, and the second communication port 94 is preferably provided in an area of ​​the case 9 facing the side facing portion 5c, and is configured so that the oil scooped up by the rotating body rotating in conjunction with the rotor 11 flows into the oil storage portion 50. More specifically, when the oil storage member 5 has a bottom surface facing portion 5a arranged opposite the bottom surface 9b of the case 9 and a side surface facing portion 5c arranged opposite the side surface 9c of the case 9, the first communication port 93 is preferably provided in an area of ​​the case 9 facing the bottom surface facing portion 5a and configured to connect the lower area E9 inside the case 9 with the oil storage portion 50, and the second communication port 94 is preferably provided in an area of ​​the case 9 facing the side surface facing portion 5c and configured so that oil scooped up by the rotating body rotating in conjunction with the rotor 11 flows into the oil storage portion 50. In addition, when the oil storage member 5 has a bottom surface opposing portion 5a arranged opposite the bottom surface 9b of the case 9, a side surface opposing portion 5c arranged opposite the side surface 9c of the case 9, and an axially opposing portion 5d arranged to overlap with the case 9 when viewed in the axial direction L and opposed to the case 9, it is preferable that the first communication port 93 is provided in an area of ​​the case 9 facing the axially opposing portion 5d or the bottom surface opposing portion 5a and configured to communicate the lower area E9 inside the case 9 with the oil storage portion 50, and the second communication port 94 is provided in an area of ​​the case 9 facing the side surface opposing portion 5c and configured so that oil scooped up by the rotating body rotating in conjunction with the rotor 11 flows into the oil storage portion 50.

[0030] As shown in FIG. 7, the oil storage member 5 includes a first communication port 51 connected to the first communication port 93 and a second communication port 52 connected to the second communication port 94. As shown in FIG. 4 and FIG. 5, a seal member S is disposed between the second communication port 94 and the second communication port 52, and the oil that splashes from the second communication port 94 to the outside of the case 9 is configured to be stored in the oil storage section 50 formed inside the oil storage member 5 without leaking to the outside of the case 9. Similarly, as shown in FIG. 5, a seal member S is also disposed between the first communication port 93 and the first communication port 51 so that the oil does not leak to the outside of the case 9 when the oil flows between the oil storage section 50 and the lower region E9 in the case 9.

[0031] As shown in Figures 4, 5, 6, etc., the vehicle drive device 100 includes an oil pump 6 that supplies sucked oil to at least one of the rotating electric machine 1 and the gear mechanism 4. In this embodiment, the oil pump 6 is disposed inside the oil storage member 5. By disposing the oil pump 6 inside the oil storage member 5, it is possible to simplify the mounting structure of the oil pump 6 to the vehicle drive device 100. For example, the assembly process of the vehicle drive device 100 can be simplified by assembling the oil storage member 5 and the oil pump 6.

[0032] FIG. 6 shows an example of the oil passage 7 through which the oil discharged from the oil pump 6 flows. The first oil passage 71 is a discharge oil passage to which the discharge port of the oil pump 6 is connected. The second oil passage 72 is an annular oil passage. The third oil passage 73 is an oil passage that extends above the second housing chamber E2 along the axial direction L to supply cooling oil to the stator coil 12b. The fourth oil passage 74 is an oil passage that connects the third oil passage 73 with an in-shaft oil passage 75 described later. The in-shaft oil passage 75 extends along the axial direction L from the second axial side L2 of the rotor 11 of the rotating electric machine 1 to at least the differential gear device 3. The in-shaft oil passage 75 supplies oil to bearings that rotatably support the rotor 11 and the rotor shaft 13, gears and bearings that mesh in the planetary gear mechanism 2, and gears and bearings that mesh in the differential gear device 3.

[0033] At least a portion of the first oil passage 71 is formed in the oil storage member 5. The oil storage member 5 is formed, for example, by resin molding, and an oil passage leading to the oil pump 6 can be easily formed therein. In addition, the first oil passage 71 can be connected to the oil pump 6 at the time the oil pump 6 is installed inside the oil storage member 5, so that the assembly process of the vehicle drive device 100 can also be simplified.

[0034] An intake oil passage 60 is connected to the intake port of the oil pump 6. The intake oil passage 60 extends to the first communication port 93 so as to incline downward Z2 in the vertical direction Z from the intake port of the oil pump 6 arranged on the first axial side L1 toward the second axial side L2. Since the tip of the intake oil passage 60 (the tip opposite the intake port of the oil pump 6) can be positioned further downward Z2 within the case 9, it is easy to appropriately suck in oil regardless of the amount of oil or the attitude (inclination) of the vehicle drive device 100.

[0035] Further, a partition wall portion 99 is provided in the case 9 to partition the first accommodation chamber E1 and the second accommodation chamber E2 and to support the rotor 11 and the gear mechanism 4. Even if the vehicle drive device 100 is tilted in a direction in which the second axial side L2 is the lower side Z2, the partition wall portion 99 restricts the oil flowing into the second accommodation chamber E2. Therefore, the suction oil passage 60 can appropriately suck in oil even if the vehicle is tilted with the first axial side L1 on the upper side Z1 and the second axial side L2 on the lower side Z2, and the vehicle drive device 100 is also tilted together with the vehicle.

[0036] The oil pump 6 may be disposed outside the oil storage member 5. Even in this case, it is preferable that the oil passage leading to the intake port of the oil pump 6 (the oil passage corresponding to the intake oil passage 60) opens in the lower region E9 of the case 9 or near the first flow port 51 of the oil storage member 5.

[0037] In addition, in this embodiment, the partition wall 99 is provided between the first storage chamber E1 and the second storage chamber E2, so that the mutual flow of the oil in the first storage chamber E1 and the oil in the second storage chamber E2 is restricted. In other words, the oil is configured to move so that the oil level in the first storage chamber E1 and the oil level in the second storage chamber E2 do not match quickly, but match over time. For example, when the amount of oil supplied to the second storage chamber E2 is greater than that in the first storage chamber E1 in order to cool the rotating electric machine 1, if the flow of oil between the first storage chamber E1 and the second storage chamber E2 is not restricted, the oil level in the first storage chamber E1 may rise quickly, and the agitation resistance of the oil caused by the rotor of the gear mechanism 4 may increase. If the partition wall 99 is provided as in this embodiment to suppress the rise in the oil level in the first storage chamber E1, the oil in the first storage chamber E1 can be quickly moved to the oil reservoir 50, thereby reducing the agitation resistance.

[0038] Conversely, when the amount of oil supplied to the first storage chamber E1 is greater than the amount of oil supplied to the second storage chamber E2, the partition wall portion 99 may not be provided, or even if the partition wall portion 99 is provided, the communication hole connecting the first storage chamber E1 and the second storage chamber E2 may be enlarged so that the oil level in the first storage chamber E1 and the oil level in the second storage chamber E2 can quickly match.

[0039] Other embodiments will be described below. Note that the configurations of the embodiments described below are not limited to being applied independently, and may be applied in combination with the configurations of other embodiments as long as no contradiction occurs.

[0040] (1) In the above, an embodiment in which the oil storage portion 50 is formed inside the oil storage member 5 has been described as an example. However, the present invention is not limited to such a configuration. The oil storage member 5 may be disposed in contact with the outer surface of the case 9 via the seal member S, and the oil storage portion 50 may be formed between the oil storage member 5 and the outer surface of the case 9.

[0041] (2) In the above, the gear mechanism 4 includes a reduction gear using the planetary gear mechanism 2 and a differential gear device 3. However, the gear mechanism 4 may include only one of the planetary gear mechanism 2 and the differential gear device 3. For example, the gear mechanism 4 may include only the differential gear device 3 without including the planetary gear mechanism 2. The differential gear device 3 is not limited to a bevel gear type, and may be a planetary gear type. For example, the vehicle drive device 100 is not limited to a type that drives a pair of wheels W, and may be a type that drives one wheel W. In this case, the gear mechanism 4 does not need to include the differential gear device 3 for distributing power, and the gear mechanism 4 may include only the reduction gear using the planetary gear mechanism 2.

[0042] (3) In the above, an example has been given in which the case 9 has the first communication port 93 and the second communication port 94, and the oil storage member 5 has the first flow port 51 and the second flow port 52. However, the present invention is not limited to this example, and the case 9 may have a third communication port, and the oil storage member 5 may have a third flow port connected to the third communication port.

[0043] The vehicle drive device (100) described above will be briefly summarized below.

[0044] In one embodiment, the vehicle drive device (100) includes a rotating electric machine (1) having a rotor (11), an output member (31, DS) arranged coaxially with the rotating electric machine (1) and drivingly connected to wheels (W), a gear mechanism (4) that transmits driving force between the rotating electric machine (1) and the output member (31, DS), and a case (9) that houses the rotating electric machine (1) and the gear mechanism (4), and is attached to the outside of the case (9). The case (9) further includes an oil storage member (5) having an oil storage portion (50) formed therein, and the oil storage portion (50) is in communication with the interior of the case (9) via communication portions (93, 94) provided in the case (9). The communication portions (93, 94) include a first communication port (93) and a second communication port (94) positioned above (Z1) the first communication port (93), and are configured so that oil circulates between the interior of the case (9) and the oil storage portion (50).

[0045] In a configuration in which the rotating electric machine (1) and the output member (31, DS) are arranged on the same axis, there is often less excess space in the case (9) than in a configuration in which the rotating electric machine (1) and the output member (31, DS) are arranged on different axes. Therefore, in order to form an oil storage section that reserves a sufficient amount of oil in the lower part of the case (9) while suppressing the oil stirring resistance caused by the gear mechanism (4) and the rotating electric machine (1) to a small amount, it is necessary to form a case shape that reserves a large space below (Z2) the gear mechanism (4) and the rotating electric machine (1), and the case (9) is likely to become large. According to this configuration, by providing the oil storage member (5) attached to the outside of the case (9), it is possible to reserve oil in the oil storage section (50) formed on the outside of the case (9) using the oil storage member (5). Therefore, it is possible to reduce the amount of oil inside the case (9) while securing the amount of oil required for the vehicle drive device (100). Therefore, it is easy to reduce the oil stirring resistance caused by the gear mechanism (4) and the rotating electric machine (1) housed in the case (9), and it is also easy to reduce the size of the case (9).

[0046] Furthermore, in the vehicle drive device (100), it is preferable that the oil storage member (5) has a bottom facing portion (5a) arranged opposite the bottom surface (9b) of the case (9), and that the bottom facing portion (5a) is arranged so as to overlap with either the gear mechanism (4) or the rotating electric machine (1), whichever has a smaller outer diameter, when viewed in the vertical direction (Z).

[0047] According to this configuration, the oil storage member (5) is arranged so as to overlap, when viewed in the vertical direction (Z), with either the rotating electric machine (1) or the gear mechanism (4), whichever has the smaller outer diameter. Therefore, the oil storage section (50) can be formed on the outside of the case (9) while preventing the overall diameter of the vehicle drive device (100) from becoming larger.

[0048] In addition, in the vehicle drive device (100), a direction along an axis (X) on which the rotating electric machine (1) and the gear mechanism (4) are arranged is defined as an axial direction (L), and the oil storage member (5) includes a side facing portion (5c) arranged to face a side surface (9c) of the case (9) and an axial facing portion (5d) arranged to overlap with the case (9) as viewed in the axial direction (L) and face the case (9). It is preferable that the second communication port (94) is provided in a region of the case (9) facing the axial opposing portion (5d) so as to communicate between a lower region (E9) inside the case (9) and the oil storage portion (50), and the second communication port (94) is provided in a region of the case (9) facing the side opposing portion (5c) so as to allow oil scooped up by a rotating body rotating in conjunction with the rotor (11) to flow into the oil storage portion (50).

[0049] According to this configuration, the oil scooped up by the rotor can be caused to flow into the oil reservoir (50) through the second communication port (94), so that the amount of oil around the rotor inside the case (9) while the vehicle is running can be kept small, and the agitation resistance of the oil caused by the rotor can be kept small. Furthermore, according to this configuration, the lower area inside the case is in communication with the oil reservoir through the first communication port (93), so that the flow of oil between the inside of the case and the oil reservoir can be ensured.

[0050] In addition, the vehicle drive device (100) further includes an oil pump (6) that supplies sucked oil to at least one of the rotating electric machine (1) and the gear mechanism (4), and it is preferable that the oil pump (6) is disposed inside the oil storage member (5) and at least a portion of an oil passage (7) connected to the oil pump (6) is formed in the oil storage member (5).

[0051] According to this configuration, the oil pump (6) is disposed inside the oil storage member (5), thereby simplifying the structure for mounting the oil pump (6) to the vehicle drive device (100). For example, the assembly process of the vehicle drive device (100) can be simplified by assembling the oil storage member (5) and the oil pump (6). In addition, it is easy to facilitate the arrangement of the oil passage (7), such as the oil flow path between the oil storage portion (50) and the oil pump (6). [Explanation of symbols]

[0052] 1: rotating electric machine, 4: gear mechanism, 5: oil storage member, 5a: underside facing portion, 5c: side facing portion, 5d: axial facing portion, 6: oil pump, 7: oil passage, 9: case, 9b: underside, 9c: side, 11: rotor, 31: differential side gear (output member), 50: oil storage portion, 60: intake oil passage (oil passage leading to oil pump), 71: first oil passage (oil passage leading to oil pump), 93: first communication port, 94: second communication port, 100: vehicle drive device, DS: drive shaft (output member), E9: lower region, L: axial direction, W: wheel, Z: up-down direction, Z1: upper side, Z2: lower side

Claims

1. A rotating electric machine having a rotor; an output member that is disposed coaxially with the rotating electric machine and is drivingly connected to wheels; a gear mechanism that transmits a driving force between the rotating electric machine and the output member; a case that houses the rotating electric machine and the gear mechanism, The oil storage member is attached to the outside of the case and has an oil storage portion formed therein. The oil reservoir communicates with the inside of the case via a communication portion provided in the case, The communication portion includes a first communication port and a second communication port positioned above the first communication port, and is configured to allow oil to circulate between the inside of the case and the oil storage portion.

2. The oil storage member includes a lower surface facing portion disposed opposite a lower surface of the case, The vehicle drive device according to claim 1 , wherein the lower surface opposed portion is disposed so as to overlap, when viewed in the up-down direction, either the gear mechanism or the rotating electric machine, whichever has a smaller outer diameter.

3. A direction along an axis on which the rotating electric machine and the gear mechanism are arranged is defined as an axial direction, The oil storage member includes a side facing portion arranged to face a side surface of the case, and an axial facing portion arranged to overlap with the case when viewed in the axial direction and to face the case, the first communication port is provided in a region of the case facing the axially opposing portion and configured to communicate between a lower region inside the case and the oil reservoir, 3. The vehicle drive device according to claim 2, wherein the second communication port is provided in an area of ​​the case facing the side facing portion, and is configured so that oil scooped up by a rotating body rotating in conjunction with the rotor flows into the oil storage portion.

4. an oil pump that supplies the sucked oil to at least one of the rotating electric machine and the gear mechanism; The vehicle drive device according to claim 1 , wherein the oil pump is disposed inside the oil storage member, and at least a portion of an oil passage leading to the oil pump is formed in the oil storage member.

Images