Vehicle drive device

Abstract

A vehicle drive device (10) is such that: a first axis (A1), which is the rotational axis of a rotating electrical machine (1), is disposed on the upper side (V1) of a second axis (A2), which is the rotational axis of a counter gear mechanism (3); the second axis (A2) is disposed on the upper side (V1) of a third axis (A3), which is the rotational axis of a pair of output members; the third axis (A3) is disposed closer to a first side (Xr) in the front-rear direction than the first axis (A1) and the second axis (A2); an inverter module (7) is disposed closer to the first side (Xr) in the front-rear direction than the first axis (A1) and the second axis (A2) and is disposed on the upper side (V1) of the third axis (A3); the vertical-direction (V) disposition region of the inverter module (7) overlaps the vertical-direction (V) disposition region of the rotating electrical machine (1); and the front-rear direction (X) disposition region of the inverter module (7) overlaps the front-rear direction (X) disposition region of a differential gear mechanism (4).

Description

Vehicle drive unit

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

[0002] Japanese Patent Application Laid-Open Publication No. 2022-44049 discloses a vehicle drive device (100) including a rotating electric machine (1) that serves as a driving force source for a pair of wheels (W), a pair of output members (6) drivingly coupled to the pair of wheels (W), and a transmission mechanism (3) that transmits power between the rotating electric machine (1) and the pair of output members (6) (reference numerals in parentheses in the Background Art section refer to those in the referenced document). The transmission mechanism (3) also includes a counter gear mechanism (4) and a differential gear mechanism (5), with the rotating electric machine (1) disposed on a first shaft (C1), the output members (6) and the differential gear mechanism (5) disposed on a second shaft (C2), and the counter gear mechanism (4) disposed on a third shaft (C3). The case (2) of the vehicle drive device (100) accommodates the rotating electric machine (1), the output members (6), the transmission mechanism (3), and an inverter module (90) that drives and controls the rotating electric machine (1). The inverter module (90) is arranged adjacent to the rotating electric machine (1), the output member (6), and the transmission mechanism (3) on one side of the front-to-rear direction (X) perpendicular to the up-down direction (Y) and the axial direction (L) when viewed in the axial direction (L) along the first axis (C1), the second axis (C2), and the third axis (C3) (see Figures 1 to 9 of the document, etc.).

[0003] Japanese Patent Application Laid-Open No. 2022-44049

[0004] As described above, when the inverter module is disposed adjacent to a drive mechanism such as a rotating electric machine or a transmission mechanism in the horizontal direction (axial direction or front-rear direction), the inverter module is often disposed horizontally offset from the drive mechanism so as not to interfere with the horizontal positioning of the inverter module. The above-mentioned document also shows a configuration in which the inverter module is disposed offset in the front-rear direction from the rotating electric machine or the transmission mechanism. When the inverter device is disposed offset in the horizontal direction, the front-rear and axial dimensions of the vehicle drive system tend to increase, which hinders the miniaturization of the vehicle drive system.

[0005] In view of the above background, it is desirable to provide a technology that can facilitate miniaturization of a vehicle drive device that includes a rotating electric machine in a drive mechanism and an inverter module that drives and controls the rotating electric machine.

[0006] In view of the above, a vehicle drive device includes a rotating electric machine having a rotor, an inverter module that drives and controls the rotating electric machine, a pair of output members that are respectively drivingly connected to wheels, an input gear that rotates integrally with the rotor, a counter gear mechanism that includes a first counter gear that meshes with the input gear and a second counter gear that is connected to rotate integrally with the first counter gear, and a differential gear mechanism that includes an output gear that meshes with the second counter gear and is disposed coaxially with the pair of output members to distribute rotation of the output gear to the pair of output members, wherein the direction along a first axis that is the rotation axis of the rotor is defined as an axial direction, and a direction perpendicular to both the axial direction and the up-down direction is defined as a front-rear direction, With one side in the fore-and-aft direction being the first side in the fore-and-aft direction, the first axis is positioned above the second axis, which is the rotation axis of the counter gear mechanism, the second axis is positioned above the third axis, which is the rotation axis of the pair of output members, the third axis is positioned on the first side in the fore-and-aft direction of the first axis and the second axis, the inverter module is positioned on the first side in the fore-and-aft direction of the first axis and the second axis and above the third axis, the vertical placement area of ​​the inverter module overlaps with the vertical placement area of ​​the rotating electric machine, and the vertical placement area of ​​the inverter module overlaps with the vertical placement area of ​​the differential gear mechanism.

[0007] According to this configuration, the first, second, and third shaft centers are arranged in this order from top to bottom in the vertical direction, allowing the main components of the drive mechanism in the vehicle drive device to be aligned vertically, thereby facilitating a reduction in the longitudinal dimension of the vehicle drive device. Furthermore, because the third shaft center is located on the first longitudinal side of the first and second shaft centers, a space can be formed on the first longitudinal side of the first and second shaft centers and above the third shaft center, allowing an inverter module to be disposed using this space. Therefore, the increase in the longitudinal dimension of the vehicle drive device due to the inverter module placement can be kept to a minimum, facilitating a reduction in the size of the vehicle drive device. In other words, according to this configuration, it is possible to easily reduce the size of a vehicle drive device that includes a rotating electric machine in the drive mechanism and an inverter module that drives and controls the rotating electric machine.

[0008] Further features and advantages of the vehicle drive device will become apparent from the following description of exemplary, non-limiting embodiments which are given with reference to the drawings.

[0009] Schematic exploded perspective view of a vehicle drive device; Skeleton diagram of a vehicle drive device; Schematic block diagram of a system for driving a rotating electric machine; Side view of a vehicle drive device from a first axial side; Side view (front view) of a vehicle drive device from a first front-rear side

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a vehicle drive device will be described below with reference to the accompanying drawings. In the schematic exploded perspective view of FIG. 1, some components, such as a part of a cover member that constitutes a case 9, are omitted.

[0011] In the following description, the term "driving connection" refers to a state in which two rotating elements are connected so as to be able to transmit a driving force, and includes a state in which the two rotating elements are connected so as to rotate integrally, or a state in which the two rotating elements are connected so as to be able to transmit a driving force via one or more transmission members. Such transmission members include various members that transmit rotation at the same speed or at a variable speed, such as shafts, gear mechanisms, belts, and chains. Note that transmission members may also include engagement devices that selectively transmit rotation and driving force, such as friction engagement devices and meshing engagement devices. However, when the term "driving connection" is used to refer to each rotating element of a planetary gear mechanism, it refers to a state in which multiple rotating elements in the planetary gear mechanism are connected to each other without passing through other rotating elements.

[0012] Furthermore, with regard to the arrangement of two elements, "overlapping when viewed in a specific direction" means that when an imaginary line parallel to the line of sight is moved in each direction perpendicular to the imaginary line, there is at least a part of an area where the imaginary line intersects with both of the two elements. Furthermore, with regard to the arrangement of two elements, "arrangement areas in a specific direction overlap" means that the arrangement area of ​​one element in a specific direction contains at least a part of the arrangement area of ​​the other element in a specific direction.

[0013] As shown in FIGS. 1 and 2 , a vehicle drive system 10 includes a rotating electric machine 1, an input member 2, a counter gear mechanism 3, a differential gear mechanism 4, and a case 9. The case 9 houses the rotating electric machine 1, the input member 2, the counter gear mechanism 3, and the differential gear mechanism 4. The rotating electric machine 1 is an inner rotor type rotating electric machine in which a rotor 11 is disposed radially inward R1 relative to a stator 15. The input member 2 is connected to the rotor 11 of the rotating electric machine 1 so as to rotate integrally with the rotor 11. In this embodiment, the input member 2 is spline-coupled to a rotor shaft 20 connected to the rotor 11, and rotates integrally with the rotor 11 and the rotor shaft 20. Note that the rotor shaft 20 and the input member 2 may be the same member. The differential gear mechanism 4 distributes driving force transmitted from the rotating electric machine 1 to a pair of output members drivingly connected to a pair of wheels W. In this embodiment, a pair of differential side gears 45 of the differential gear mechanism 4, which will be described later, correspond to the output members.

[0014] The vehicle drive system 10 includes a speed reduction mechanism that reduces the rotation of the input member 2 and transmits the reduced rotation to a differential case 42 of the differential gear mechanism 4. As shown in FIG. 2 , in this embodiment, the speed reduction mechanism includes an input gear 21, a counter gear mechanism 3, and a differential input gear 41. The input gear 21 is connected to the input member 2 so as to rotate integrally with the input member 2. The input gear 21 may be formed integrally with the input member 2, which is a shaft member, using the same member, or may be formed using a member separate from the input member 2 and integrated with the input member 2 by welding or the like. Similarly, a first counter gear 31 and a second counter gear 32, which will be described later, may be formed using the same member as the shaft member (counter shaft 30) or may be separate members, and the differential input gear 41 may be formed using the same member as the differential case 42 or may be separate members.

[0015] The counter gear mechanism 3 includes a first counter gear 31 and a second counter gear 32. The first counter gear 31 and the second counter gear 32 are both connected to the counter shaft 30 so as to rotate integrally. The first counter gear 31 meshes with the input gear 21, and the second counter gear 32 meshes with a differential input gear 41. The differential input gear 41 is connected to the differential case 42 so as to rotate integrally therewith.

[0016] As shown in FIG. 2 , the rotating electric machine 1 (rotor 11) and the input member 2 are disposed on a first axis A1 (first axis). The counter gear mechanism 3 is disposed on a second axis A2 (second axis), which is a separate axis parallel to the first axis A1. The differential gear mechanism 4, including the output member, is disposed on a third axis A3 (third axis), which is a separate axis parallel to the first axis A1 and the second axis A2. In this embodiment, as shown in FIG. 1 , the first axis A1 is disposed on a side V1 above the second axis A2 and the third axis A3. While this embodiment illustrates an example in which the second axis A2 is disposed on the side V1 above the third axis A3, the second axis A2 and the third axis A3 may be disposed at the same position in the vertical direction V, or the third axis A3 may be disposed on the side V1 above the second axis A2.

[0017] In the following description, a direction parallel to the first axis A1, the second axis A2, and the third axis A3 is referred to as the "axial direction L" of the vehicle drive device 10. One side of the axial direction L is referred to as the "axial first side L1," and the other side of the axial direction L is referred to as the "axial second side L2." The direction in which the rotating members revolve around their respective rotational axes is referred to as the "circumferential direction C" (see FIG. 1). The directions perpendicular to the first axis A1, the second axis A2, and the third axis A3 are referred to as the "radial direction R" based on each axis (see FIG. 1). The side closer to the axis in the radial direction R is referred to as the "radial inner side R1," and the side farther from the axis is referred to as the "radial outer side R2." Note that when it is not necessary to distinguish which axis is used as the reference or when it is clear which axis is used as the reference, the term "radial direction R" may be used simply.

[0018] Furthermore, in a state in which the vehicle drive device 10 is mounted on a vehicle, the direction along the vertical direction is referred to as the up-down direction V, and the upper side along the up-down direction V is referred to as the upper side V1, and the lower side along the up-down direction V is referred to as the lower side V2. In this embodiment, in a state in which the vehicle is mounted, the axial direction L is along the horizontal direction, and the axial direction L and the up-down direction V are orthogonal to each other. In this state, the direction orthogonal to the axial direction L and the up-down direction V is referred to as the fore-aft direction X, and one side of the fore-aft direction X is referred to as the "first fore-aft direction side Xr," and the other side of the fore-aft direction X is referred to as the "second fore-aft direction side Xf."

[0019] In this embodiment, the rotating electric machine 1 is exemplified as an electrically excited synchronous motor (EESM) having a stator 15 with a plurality of phases (N phases, e.g., three phases, where N is an arbitrary natural number) of stator coils 17 arranged thereon, and a wound-field rotor 11. The wound-field synchronous rotating electric machine has a rotor structure with an electromagnet using a field winding (rotor coil 13) instead of a permanent magnet as a field source. The field magnetic flux generated by the electromagnet is controlled by a rotating electric machine control device 70 (described later) and can be adjusted by a field current supplied to the rotor winding 13 from an excitation circuit 72 (both included in an inverter module 7 (described later)) via a wireless power supply 18 and a rectifier circuit 19 (see FIG. 2 ). The excitation circuit 72 includes a switching element and adjusts the DC voltage supplied from the DC power source 6 so as to pass a set field current through the rotor winding 13. The power generated by the excitation circuit 72 is transmitted as AC via the non-contact power supply unit 18 , converted to DC by the rectifier circuit 19 , and supplied to the rotor coil 13 .

[0020] As described above, the EESM generates a field in the rotor 11 by passing a field current through the rotor winding 13, but because the rotor 11 rotates, it is necessary to provide a structure for passing a field current in the same direction through the rotor winding 13. In this embodiment, the direction of the field current is electrically controlled by providing a contactless power supply unit 18 that transmits power contactlessly from the excitation circuit 72 and a rectifier circuit 19. However, this does not preclude a structure that mechanically switches the direction of the field current, for example, by providing brushes.

[0021] Wound-field synchronous rotating electric machines have advantages over permanent magnet synchronous motors (PMSMs), such as (1) variable field flux, which is expected to improve efficiency in the medium-to-high speed / low torque operating range and expand the constant output range, and (2) they are not affected by supply instability of permanent magnets using rare earths, etc. For this reason, in recent years, they have also been increasingly used as a driving force source for the wheels of electric vehicles and hybrid vehicles. In light of this background, although an EESM is used as an example of the rotating electric machine 1 in this embodiment, the rotating electric machine 1 may have other structures, such as a PMSM.

[0022] The vehicle drive device 10 includes an inverter module 7 that drives and controls the rotating electric machine 1. As shown in Fig. 3 , in this embodiment, the inverter module 7 includes a rotating electric machine control device 70 (e.g., a control board) that controls the rotating electric machine 1, which serves as a driving force source for the vehicle, an inverter 71 (e.g., a power element module) that is switching controlled by the rotating electric machine control device 70 to supply current to the stator coil 17, an excitation circuit 72 that is switching controlled by the rotating electric machine control device 70 to excite the rotor winding 13, and a smoothing capacitor 77. Note that the inverter module 7 is only required to include at least the inverter 71, and any one or more of the rotating electric machine control device 70, the smoothing capacitor 77, and the excitation circuit 72 may be configured separately from the inverter module 7.

[0023] The rotating electric machine 1 is an AC rotating electric machine that functions as a motor powered by power supplied from a DC power source 6 and as a generator that generates power using power transmitted from the wheels W and supplies (regenerates) the power to the DC power source 6. The inverter 71 is connected to the AC rotating electric machine 1 and the DC power source 6, and converts power between multi-phase AC and DC. A pair of DC side terminals of the inverter 71 are connected to both positive and negative terminals of the DC power source 6. Furthermore, the multi-phase AC side terminals of the inverter 71 are connected to the multi-phase stator coils 17, respectively. A smoothing capacitor 77 (DC link capacitor) that smoothes the voltage between the positive and negative poles (DC link voltage Vdc) is provided on the DC side of the inverter 71.

[0024] The inverter 71 is configured to have a plurality of switching elements. Similarly, the excitation circuit 72 is configured to have a plurality of switching elements. As the switching elements, it is preferable to use power semiconductor elements capable of operating at high frequencies, such as an IGBT (Insulated Gate Bipolar Transistor), a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor), a SiC-MOSFET (Silicon Carbide-Metal Oxide Semiconductor FET), a SiC-SIT (SiC-Static Induction Transistor), or a GaN-MOSFET (Gallium Nitride-MOSFET).

[0025] The DC power supply 6 is configured by, for example, a rechargeable secondary battery (battery) such as a lithium ion battery, an electric double layer capacitor, etc. When the rotating electric machine 1 is used as a driving power source for a vehicle as in this embodiment, the DC power supply 6 is a high-voltage, large-capacity DC power supply with a rated power supply voltage of 200 volts or more.

[0026] The inverter 71 is controlled by a rotating electric machine control device 70. The rotating electric machine control device 70 is constructed with a logic circuit such as a microcomputer as its core component. For example, the rotating electric machine control device 70 performs current feedback control using a vector control method based on a target torque (torque command) for the rotating electric machine 1 provided as a request signal from another control device such as a vehicle control device 60, which is one of the higher-level control devices, to drive the rotating electric machine 1 via the inverter 71 and the excitation circuit 72. The operating voltage of logic circuit elements such as a microcomputer is approximately 3.3 to 5 volts. In this embodiment, although not shown for simplicity, control signals generated by the logic circuit elements are transmitted to the inverter 71 and the excitation circuit 72 via a drive circuit.

[0027] The actual current flowing through the stator coil 17 of each phase of the rotating electric machine 1 is detected by a current sensor (motor current sensor 81), and the rotating electric machine control device 70 acquires the detection results. In addition, the rotational position and rotational speed (angular velocity) of the rotor 11 of the rotating electric machine 1 at each point in time are detected by a rotation sensor 82, such as a resolver or an inductive position sensor, and the rotating electric machine control device 70 acquires the detection results. The rotating electric machine control device 70 performs current feedback control using the detection results of the motor current sensor 81 and the rotation sensor 82. The rotating electric machine control device 70 is configured to have various functional units for current feedback control, and each functional unit is realized by cooperation between hardware such as a microcomputer and software (programs).

[0028] 1 and 2, the input member 2, input gear 21, counter gear mechanism 3, and differential gear mechanism 4 are disposed on the first axial side L1 with respect to the rotary electric machine 1. As described above, the input member 2, which rotates integrally with the input gear 21, is connected to the rotor shaft 20 so as to rotate integrally with the rotor shaft 20. The input member 2 is also rotatably supported with respect to the case 9 via an input bearing (not shown).

[0029] The counter gear mechanism 3 is rotatably supported relative to the case 9 via a counter bearing (not shown). Specifically, a counter shaft 30 to which a first counter gear 31 and a second counter gear 32 are connected is rotatably supported relative to the case 9 by the counter bearing.

[0030] The differential gear mechanism 4 is rotatably supported relative to the case 9 via a differential bearing (not shown). Specifically, the differential case 42 is rotatably supported relative to the case 9 via the differential bearing.

[0031] In this embodiment, a bevel gear type differential gear mechanism 4 is illustrated. The differential gear mechanism 4 includes a plurality of differential pinion gears 44 housed in a differential case 42 and a pair of differential side gears 45. The differential pinion gears 44 are rotatably supported by differential pinion shafts 43 that are fixed to the differential case 42 and rotate integrally with the differential case 42. A plurality of differential pinion shafts 43 are provided radially (e.g., in a cross shape) along a radial direction R based on the third axis A3, and a plurality of differential pinion gears 44 are also arranged at intervals in the radial direction R. The pair of differential side gears 45 mesh with the plurality of differential pinion gears. The differential side gears 45 are arranged to rotate about the third axis A3. Of the pair of differential side gears 45, the first differential side gear 45 is arranged on a first axial side L1 relative to the differential pinion shaft 43, and the second differential side gear 45 is arranged on a second axial side L2 relative to the differential pinion shaft 43.

[0032] In this embodiment, the first differential side gear 45 arranged on the first axial side L1 is connected to a first drive shaft DS, and the first drive shaft DS is connected to a first wheel W. The second differential side gear 45 arranged on the second axial side L2 is connected to a connecting shaft JS, which is connected to a second drive shaft DS, and the second drive shaft DS is connected to a second wheel W. Since the pair of drive shafts DS and connecting shaft JS rotate integrally with the respective differential side gears 45, the pair of drive shafts DS and connecting shaft JS can also be considered a pair of output members.

[0033] Although a bevel gear type differential gear mechanism 4 has been exemplified here, the differential gear mechanism 4 may also be a planetary gear mechanism. For example, if the differential gear mechanism 4 is a double pinion type planetary gear mechanism, a member that rotates integrally with the carrier and a member that rotates integrally with the sun gear correspond to the output member.

[0034] The case 9 has a first storage chamber E1 that houses the drive mechanism TA, such as the rotating motor 1, input member 2, input gear 21, counter gear mechanism 3, and differential gear mechanism 4, and a second storage chamber E2 that is partitioned from the first storage chamber E1 and houses the inverter module 7, which includes the rotating motor control device 70, inverter 71, excitation circuit 72, smoothing capacitor 77, etc.

[0035] The case 9 includes a case main body 90, which forms the core of the first storage chamber E1 and the second storage chamber E2, a first cover 91, a second cover (not shown), and a third cover 93. The case main body 90 includes a cylindrical portion having openings on both sides in the axial direction L, and a box-shaped portion having a side wall portion forming a rectangular opening extending from the peripheral wall of the cylindrical portion to one side in the front-rear direction X (here, the first front-rear direction side Xr). The first cover 91 is a lid member that closes the opening on the first axial side L1 of the cylindrical portion of the case main body 90 from the first axial side L1 (see FIG. 1 ). The second cover is a lid member that closes the opening on the second axial side L2 of the cylindrical portion of the case main body 90 from the second axial side L2. The third cover 93 is a lid member that closes the opening on the first front-rear direction side Xr of the box-shaped portion of the case main body 90. A first storage chamber E1 is formed in a space surrounded by the inner wall of the cylindrical portion of the case body 90, the first cover 91, and the second cover. A second storage chamber E2 is formed in a space surrounded by the outer wall of the cylindrical portion of the case body 90, the side wall of the box-shaped portion, and the third cover 93.

[0036] Since the inverter module 7 is accommodated in the second accommodation chamber E2 of the case 9, the case 9 is also provided with a first connector CN1 to which power wiring from the high-voltage DC power supply 6 is connected (see FIGS. 4 and 5 ). The case 9 is also provided with a second connector CN2 to which power wiring of about 12 volts is connected to supply drive power to the rotating electrical machine control device 70 in the inverter module 7 and signal wiring connected to a control device higher in level than the inverter module 7 (e.g., a vehicle control device 60 that controls the entire vehicle) and various sensors are connected. A coolant supply port Wi serving as an inlet for coolant for cooling the inverter 71 and smoothing capacitor 77 of the inverter module 7, the drive mechanism TA, oil accommodated in the case 9 to lubricate and cool the drive mechanism TA, and a coolant discharge port (not shown) serving as an outlet for coolant are also provided on the case 9 and on a component attached to the case 9 (e.g., an oil cooler (not shown) that cools the oil).

[0037] As described above, the vehicle drive device 10 of this embodiment includes the rotating electric machine 1, the inverter module 7, a pair of output members, the input gear 21, the counter gear mechanism 3, and the differential gear mechanism 4. The first axis A1 on which the rotating electric machine 1 is disposed is disposed on the upper side V1 of the second axis A2 on which the counter gear mechanism 3 is disposed. The second axis A2 is also disposed on the upper side V1 of the third axis A3 on which a pair of output members (such as the differential side gears 45) are disposed. The third axis A3 is also disposed on the first side Xr in the front-rear direction of the first axis A1 and the second axis A2.

[0038] In this embodiment, the first axis A1, the second axis A2, and the third axis A3 are arranged in order from top to bottom in the vertical direction V, and the main components of the drive mechanism TA in the vehicle drive device 10 are arranged along the vertical direction V. In particular, in this embodiment, the first axis A1 and the second axis A2 are arranged at approximately the same position in the front-rear direction X. Therefore, in the three-axis vehicle drive device 10, it is easy to shorten the dimension in the front-rear direction X.

[0039] 4, the third axis A3 is disposed on the first side Xr in the front-rear direction relative to the first axis A1 and the second axis A2. As a result, the dimension of the vehicle drive device 10 in the front-rear direction X is slightly larger than when all three axes are aligned in a straight line along the up-down direction V, but the increase in dimension in the up-down direction V is suppressed. Also, as shown in FIG. 4, it is easy to ensure a space (second accommodation chamber E2) in which the drive mechanism TA is not disposed, on the first side Xr in the front-rear direction relative to the first axis A1 and the second axis A2 and above the side V1 of the third axis A3.

[0040] The inverter module 7 is disposed in a second housing chamber E2 formed in the space within the case 9. That is, the inverter module 7 is disposed on the first side Xr in the front-rear direction of the first axis A1 and the second axis A2 and on the upper side V1 of the third axis A3. Preferably, the entire inverter module 7 is disposed on the first side Xr in the front-rear direction of the first axis A1 and the second axis A2 and on the upper side V1 of the third axis A3. As a result, the arrangement area of ​​the inverter module 7 in the up-down direction V overlaps with the arrangement area of ​​the rotating electric machine 1 in the up-down direction V as shown in FIGS. 4 and 5 , and the arrangement area of ​​the inverter module 7 in the up-down direction X overlaps with the arrangement area of ​​the differential gear mechanism 4 in the up-down direction X as shown in FIG. 4 .

[0041] 4 and 5 , the present embodiment illustrates a configuration in which the arrangement area of ​​the inverter module 7 in the up-down direction V does not overlap with the arrangement area of ​​the differential gear mechanism 4 in the up-down direction V. However, as long as the inverter module 7 is arranged above the third axis A3, this does not preclude a configuration in which part of the arrangement area of ​​the differential gear mechanism 4 in the up-down direction V (for example, part of the upper side V1 of the differential input gear 41) overlaps with the arrangement area of ​​the inverter module 7 in the up-down direction V.

[0042] 5, in this embodiment, the arrangement area of ​​the inverter module 7 in the axial direction L overlaps with the arrangement area of ​​the drive mechanism TA (the rotating electric machine 1, the counter gear mechanism 3, and the differential gear mechanism 4) in the axial direction L. However, all of the arrangement areas of the drive mechanism TA in the axial direction L do not have to overlap with the arrangement area of ​​the inverter module 7 in the axial direction L. As shown in FIG. 3, since it is the rotating electric machine 1 that is electrically connected to the inverter module 7, it is preferable that the inverter module 7 overlaps with at least the arrangement area of ​​the rotating electric machine 1 in the axial direction L.

[0043] 4, in this embodiment, the end of the inverter module 7 on the second front-rear direction side Xf is disposed closer to the second front-rear direction side Xf than the third axis A3. In addition, when viewed in the axial direction, the second axis A2 is disposed on the second front-rear direction side Xf (opposite the side on which the inverter module 7 is disposed) with respect to an imaginary line (imaginary plane) passing through the first axis A1 and the third axis A3.

[0044] In this embodiment, the length of the arrangement area in the vertical direction V of the drive mechanism TA, which is a combination of the rotating electric machine 1 and the counter gear mechanism 3 arranged on two axes, the first axis A1 and the second axis A2, which are aligned in the vertical direction V, is longer than the length of the arrangement area in the front-rear direction X of the differential gear mechanism 4 arranged on the third axis A3, which is a single axis. Therefore, it is easy to form the space on the first side Xr in the front-rear direction relative to the first axis A1 and the second axis A2 and on the upper side V1 in the vertical direction V relative to the third axis A3 so that the dimension in the vertical direction V is larger than the dimension in the front-rear direction X.

[0045] 1 and 4 , when the vehicle drive device 10 is mounted on the vehicle, the inverter module 7 is disposed in the second housing chamber E2 within the case 9 in an orientation such that the dimension in the up-down direction V is greater than the dimension in the front-rear direction X. That is, the inverter module 7 is appropriately housed in a space (second housing chamber E2) that can be easily formed so that the dimension in the up-down direction V is greater than the dimension in the front-rear direction X, as described above. In other words, by disposing the inverter module 7 in the above orientation, the dimension of the vehicle drive device 10 in the front-rear direction X can be kept small, making it easy to miniaturize the vehicle drive device 10. Therefore, it is easy to achieve miniaturization of the vehicle drive device 10 with the inverter module 7 housed within the case 9.

[0046] In this embodiment, the inverter module 7 not only has a dimension in the up-down direction V that is greater than a dimension in the front-rear direction X, but also has a dimension in the axial direction L that is greater than the dimension in the up-down direction V, as shown in FIG.

[0047] Furthermore, since the shape of the space corresponding to the second storage chamber E2 differs depending on the size of each mechanism that constitutes the drive mechanism TA, this does not prevent the inverter module 7 from being configured such that its dimension in the front-to-back direction X is larger than its dimension in the up-down direction V, or such that its dimension in the up-down direction V is larger than its dimension in the axial direction L.

[0048] 4, in this embodiment, the inverter module 7 is disposed so as not to protrude further toward the first front-rear side Xr than the end of the differential gear mechanism 4 on the first front-rear side Xr. Since the inverter module 7 does not protrude further toward the first front-rear side Xr than the drive mechanism TA, which is a main component of the vehicle drive device 10, the vehicle drive device 10 can be easily configured to be compact without increasing the dimension of the vehicle drive device 10 in the front-rear direction X. Naturally, this does not prevent the inverter module 7 from being disposed so as to protrude further toward the first front-rear side Xr than the end of the differential gear mechanism 4 on the first front-rear side Xr.

[0049] 4, the inverter module 7 does not overlap with the first axis A1 and the second axis A2 when viewed in the axial direction L, and as shown in FIG. 5, the inverter module 7 overlaps with the rotating electric machine 1 and the counter gear mechanism when viewed in the front-rear direction X. That is, the inverter module 7 overlaps with the rotating electric machine 1 and the counter gear mechanism 3 in both the arrangement area in the up-down direction V and the arrangement area in the axial direction L. In other words, the arrangement area of ​​the inverter module 7 in the up-down direction V overlaps with the arrangement area of ​​the rotating electric machine 1 in the up-down direction V and the arrangement area of ​​the counter gear mechanism 3 in the up-down direction V, and the arrangement area of ​​the inverter module 7 in the axial direction L overlaps with the arrangement area of ​​the rotating electric machine 1 in the axial direction L and the arrangement area of ​​the counter gear mechanism 3 in the axial direction L.

[0050] 4, in this embodiment, the inverter module 7 overlaps with part of the rotating electric machine 1 (for example, part of the stator 15 on the first side Xr in the front-rear direction) when viewed in the axial direction, but does not overlap with the input gear 21 or the counter gear mechanism 3. Although not shown, it is preferable that the inverter module 7 does not overlap with the rotor 11 even if part of the stator 15 overlaps with the inverter module 7 when viewed in the axial direction.

[0051] 4, in a configuration in which the dimension of the inverter module 7 in the front-rear direction X is shorter than that shown in the figure and the inverter module 7 is disposed closer to the first side Xr in the front-rear direction, the vehicle drive device 10 can be configured so that the inverter module 7 does not overlap with the rotating electric machine 1 when viewed in the axial direction. In other words, the vehicle drive device 10 can also be configured so that the inverter module 7 does not overlap with the rotating electric machine 1 and the counter gear mechanism 3 when viewed in the axial direction.

[0052] Furthermore, in this embodiment, the inverter module 7 does not overlap with the third axis A3 when viewed in the axial direction L. That is, it does not overlap with any of the first axis A1, the second axis A2, and the third axis A3. Of the differential gear mechanism 4 arranged on the third axis A3, the differential case 42 (including the gear housed in the differential case 42) preferably does not overlap with the inverter module 7 when viewed in the axial direction. However, the differential input gear 41, which is also arranged on the third axis A3 and meshes with the second counter gear 32, may or may not overlap with the inverter module 7 when viewed in the axial direction.

[0053] In terms of the arrangement area, the arrangement area of ​​the inverter module 7 in the front-rear direction X does not overlap with the arrangement area of ​​the counter gear mechanism 3 in the front-rear direction X, but overlaps with the arrangement area of ​​the differential gear mechanism 4 in the front-rear direction X. Also, as described above, the arrangement area of ​​the rotating electric machine 1 in the front-rear direction X (particularly the arrangement area of ​​the stator 15 in the front-rear direction X) partially overlaps with the arrangement area of ​​the inverter module 7 in the front-rear direction X. However, this does not preclude a configuration in which the arrangement area of ​​the inverter module 7 in the front-rear direction X does not overlap with the arrangement area of ​​the rotating electric machine 1 in the front-rear direction X.

[0054] Furthermore, in this embodiment, a configuration is exemplified in which the inverter module 7 overlaps with the counter gear mechanism 3 when viewed in the front-rear direction. However, in a configuration in which the dimension of the inverter module 7 in the up-down direction V is shorter than that shown in the figure and the inverter module 7 is disposed closer to the upper side V1 in Fig. 4, the inverter module 7 may be configured not to overlap with the counter gear mechanism 3 when viewed in the front-rear direction.

[0055] When the inverter module 7 overlaps at least one of the first axis A1 on which the rotating electric machine 1, the input member 2, and the input gear 21 are arranged and the second axis A2 on which the counter gear mechanism 3 is arranged, as viewed in the axial direction L, the dimension of the vehicle drive device 10 in the axial direction L becomes larger than when there is no overlap. However, in this embodiment, the inverter module 7 does not overlap with either the first axis A1 or the second axis A2 as viewed in the axial direction, so it is easy to keep the dimension of the vehicle drive device 10 in the axial direction L small.

[0056] Furthermore, when the inverter module 7 does not overlap with the first axis A1 and the second axis A2 when viewed in the axial direction, and does not overlap with at least one of the rotating electric machine 1 and the counter gear mechanism 3 when viewed in the longitudinal direction X, the inverter module 7 will be either (i) positioned on the first longitudinal side Xr of the differential gear mechanism 4 so as to overlap with the differential gear mechanism 4 when viewed in the longitudinal direction, or (ii) positioned so as not to overlap with the drive mechanism TA, including the differential gear mechanism 4, when viewed in the longitudinal direction.

[0057] In the case of (i), since the third axis A3 is disposed on the first side Xr in the longitudinal direction relative to the first axis A1 and the second axis A2, if the inverter module 7 overlaps with the differential gear mechanism 4 in the longitudinal direction, the dimensions of the vehicle drive device 10 tend to increase in the longitudinal direction X. In the case of (ii), if the inverter module 7 does not overlap with any of the drive mechanisms TA in the longitudinal direction, the inverter module 7 needs to be shifted in the vertical direction V relative to the drive mechanisms TA, which tends to increase the dimensions of the vehicle drive device 10 in the vertical direction V.

[0058] In this embodiment, the inverter module 7 does not overlap with the first axis A1 and the second axis A2 when viewed in the axial direction, and overlaps with the rotating electric machine 1 and the counter gear mechanism 3 when viewed in the front-rear direction X. Therefore, it is easy to ensure an arrangement area for the inverter module 7 in the up-down direction V, and by appropriately arranging the inverter module 7, it is easy to make the vehicle drive device 10 compact.

[0059] As described above, the vehicle drive device 10 of this embodiment includes the contactless power supply unit 18 and the rectifier circuit 19 to pass a field current through the rotor winding 13 of the rotating electric machine 1, which is an EESM. The contactless power supply unit 18 and the rectifier circuit 19 can be collectively referred to as a power supply module that supplies power to the rotor winding 13. As shown in FIGS. 1 and 2 , the power supply module is disposed adjacent to the rotor 11 on one axial side (second axial side L2) of the rotor 11. In this embodiment, the inverter module 7 also overlaps with the power supply module when viewed in the front-rear direction.

[0060] Summary of the embodiment The vehicle drive device (10) described above will be briefly summarized below.

[0061] In one aspect, a vehicle drive device (10) includes a rotating electric machine (1) having a rotor (11), an inverter module (7) that drives and controls the rotating electric machine (1), a pair of output members (45) that are each drivingly connected to wheels (W), an input gear (21) that rotates integrally with the rotor (11), a first counter gear (31) that meshes with the input gear (21), and a second counter gear (32) that is connected to rotate integrally with the first counter gear (31). a differential gear mechanism (4) including a counter gear mechanism (3) having a first counter gear (32) and a second counter gear (32), and an output gear (41) meshing with the second counter gear (32), and arranged coaxially with the pair of output members (45), distributing rotation of the output gear (41) to the pair of output members (45); a direction along a first axis (A1) which is the rotation axis of the rotor (11) is defined as an axial direction (L); a direction perpendicular to both the axial direction (L) and the up-down direction (V) is defined as a front-back direction (X); With one side of the direction (X) being a first side (Xr) in the front-rear direction, the first axis (A1) is disposed above (V1) a second axis (A2) which is a rotation axis of the counter gear mechanism (3), the second axis (A2) is disposed above (V1) a third axis (A3) which is a rotation axis of the pair of output members (45), and the third axis (A3) is disposed on the first side (Xr) in the front-rear direction of the first axis (A1) and the second axis (A2), The inverter module (7) is disposed on the first side (Xr) in the front-rear direction of the first axis (A1) and the second axis (A2) and above the third axis (A3) (V1), and the vertical (V) placement area of ​​the inverter module (7) overlaps with the vertical (V) placement area of ​​the rotating electric machine (1), and the vertical (X) placement area of ​​the inverter module (7) overlaps with the vertical (X) placement area of ​​the differential gear mechanism (4).

[0062] According to this configuration, the first axis (A1), the second axis (A2), and the third axis (A3) are arranged in this order from top to bottom in the vertical direction (V), thereby allowing the main components of the drive mechanism (TA) in the vehicle drive device (10) to be arranged side by side in the vertical direction (V), making it easier to shorten the dimension of the vehicle drive device (10) in the fore-and-aft direction (X). Furthermore, because the third axis (A3) is arranged closer to the first side (Xr) in the fore-and-aft direction than the first axis (A1) and the second axis (A2), a space can be formed on the first side (Xr) in the fore-and-aft direction than the first axis (A1) and the second axis (A2) and above the third axis (A3). This space can be used to arrange the inverter module (7). Therefore, the increase in the dimension of the vehicle drive device (10) in the fore-and-aft direction (X) due to the arrangement of the inverter module (7) can be kept to a minimum, making it easier to miniaturize the vehicle drive device (10). In other words, with this configuration, it is possible to easily miniaturize a vehicle drive device (10) that includes a rotating electric machine (1) in a drive mechanism (TM) and an inverter module (7) that drives and controls the rotating electric machine (1).

[0063] Here, it is preferable that the vehicle drive device (10) is arranged such that the inverter module (7) is positioned in a position where the dimension in the up-down direction (V) is greater than the dimension in the front-rear direction (X).

[0064] The arrangement area in the vertical direction (V) of the mechanism arranged on two axes, the first axis (A1) and the second axis (A2), aligned in the vertical direction (V), of the drive mechanism (TA) tends to be longer than the arrangement area in the front-rear direction (X) of the mechanism arranged on a single axis, the third axis (A3). Therefore, the dimension in the vertical direction (V) of the space on the first side (Xr) in the vertical direction relative to the first axis (A1) and the second axis (A2) and above the third axis (A3) in the vertical direction (V) tends to be larger than the dimension in the front-rear direction (X). When the inverter module (7) is arranged in the above-mentioned orientation, the inverter module (7) can be appropriately arranged in the space, and the dimension in the front-rear direction (X) of the vehicle drive device (10) can be kept small, making it easier to miniaturize the vehicle drive device (10).

[0065] Furthermore, it is preferable that the vehicle drive device (10) is arranged in a state in which the inverter module (7) does not protrude further toward the first side (Xr) in the fore-and-aft direction than the end of the differential gear mechanism (4) on the first side (Xr) in the fore-and-aft direction.

[0066] If the inverter module (7) protrudes toward the first side (Xr) in the fore-and-aft direction relative to the differential gear mechanism (4), the dimension of the vehicle drive device (10) in the fore-and-aft direction (X) increases by the amount of protrusion. With this configuration, such an increase in the dimension of the vehicle drive device (10) in the fore-and-aft direction (X) can be avoided, and it is easy to keep the dimension of the vehicle drive device (10) in the fore-and-aft direction (X) small.

[0067] Furthermore, it is preferable that the vehicle drive device (10) has an inverter module (7) that does not overlap with the first axis (A1) and the second axis (A2) when viewed in the axial direction along the axial direction (L), and that overlaps with the rotating electric machine (1) and the counter gear mechanism (3) when viewed in the fore-and-aft direction along the fore-and-aft direction (X).

[0068] According to this configuration, it is easier to reduce the axial (L) dimension of the vehicle drive device (10) compared to a configuration in which the inverter module (7) overlaps with at least one of the first axis (A1) and the second axis (A2) when viewed in the front-rear direction (X). Also, compared to a configuration in which the inverter module (7) does not overlap with at least one of the rotating electric machine (1) and the counter gear mechanism (3) when viewed in the front-rear direction (X), it is easier to ensure an arrangement area for the inverter module (7) in the up-down direction (V), and by appropriately arranging the inverter module (7), it is easier to miniaturize the vehicle drive device (10).

[0069] 1: rotating electric machine, 3: counter gear mechanism, 4: differential gear mechanism, 7: inverter module, 10: vehicle drive device, 11: rotor, 21: input gear, 31: first counter gear, 32: second counter gear, 45: differential side gear (output member), 71: inverter, A1: first shaft (first shaft center), A2: second shaft (second shaft center), A3: third shaft (third shaft center), DS: drive shaft (output member), JS: connecting shaft (output member), L: axial direction, V: up-down direction, V1: upper side, W: wheel, X: front-rear direction, Xr: first side in the front-rear direction

Claims

1. A rotating electric machine comprising: a rotor; an inverter module for driving and controlling the rotating electric machine; a pair of output members each drivingly connected to wheels; an input gear rotating integrally with the rotor; a counter gear mechanism including a first counter gear meshing with the input gear and a second counter gear connected to rotate integrally with the first counter gear; and a differential gear mechanism including an output gear meshing with the second counter gear, the differential gear mechanism being arranged coaxially with the pair of output members and distributing the rotation of the output gear to the pair of output members, wherein the direction along the first axis which is the rotation axis of the rotor is defined as the axial direction, the direction perpendicular to both the axial direction and the up-down direction is defined as the front-to-rear direction, and one side of the front-to-rear direction is defined as a first side in the front-to-rear direction, the first axis is located above the second axis which is the rotation axis of the counter gear mechanism, and the second axis is located above the third axis which is the rotation axis of the pair of output members, A vehicle drive device, wherein the third axis is positioned on a first side in the longitudinal direction of the first axis and the second axis, the inverter module is positioned on the first side in the longitudinal direction of the first axis and the second axis and above the third axis, the vertical placement area of ​​the inverter module overlaps with the vertical placement area of ​​the rotating electric machine, and the vertical placement area of ​​the inverter module overlaps with the vertical placement area of ​​the differential gear mechanism.

2. The vehicle drive device according to claim 1, wherein the inverter module is disposed in an orientation such that the vertical dimension is greater than the longitudinal dimension.

3. A vehicle drive device as described in claim 1 or 2, wherein the inverter module is positioned so as not to protrude further toward the first side in the longitudinal direction than the end of the differential gear mechanism on the first side in the longitudinal direction.

4. A vehicle drive device as described in claim 1 or 2, wherein the inverter module does not overlap with the first axis and the second axis when viewed axially along the axial direction, and overlaps with the rotating electric machine and the counter gear mechanism when viewed in the fore-and-aft direction.

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