JP2019157939A - Vehicle drive unit - Google Patents

Abstract

To easily supply a sufficient quantity of lubricants to an engagement part between an input gear and an intermediate gear by a simple structure.SOLUTION: An in-wheel motor drive unit 21 has an electric motor driving wheels, a parallel-axis gear reduction gear 23 for decelerating the rotation of the electric motor, and outputting it, and a casing 25 for accommodating the parallel-axis gear reduction gear 23. The parallel-axis gear reduction gear 23 has a first gear 37 to which the rotation of the electric motor is inputted, and a second gear 35 engaged with the first gear 37. The first gear 37 is arranged at a vehicle rear side of the second gear 35, and a protrusion 56 for collecting lubricants 53 adhering to a top face 54 of the casing 25, and making them flow down to the engagement part 55 is formed at an upper region of the engagement part 55 between the first gear 37 and the second gear 35 at the top face 54 of the casing 25.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vehicle drive device that, for example, inputs a rotational driving force of an electric motor to a reduction gear, reduces the rotational speed, and transmits the reduced speed to a wheel bearing.

  As one type of conventional vehicle drive device, for example, there is an in-wheel motor drive device disclosed in Patent Document 1.

  The in-wheel motor drive device of this patent document 1 is an electric motor that generates a driving force of a wheel, a parallel shaft gear reducer that decelerates and outputs the rotation of the electric motor, and an output of the parallel shaft gear reducer. A wheel bearing for transmitting to the wheel.

  This in-wheel motor drive device has a structure in which an electric motor is housed in a motor casing and a parallel shaft gear reducer is housed in a main body casing.

  The electric motor includes a stator fixed to a motor casing, a rotor that is rotatably supported by the motor casing inside the stator, and a rotor shaft that outputs the rotation of the rotor.

  The parallel shaft gear reducer includes an input shaft, an intermediate shaft, and an output shaft. In this parallel shaft gear reducer, a first gear that is provided on the input shaft and receives rotation of the rotor meshes with a second gear that is provided on the intermediate shaft, and is provided coaxially with the second gear on the intermediate shaft. The rotation of the electric motor is decelerated by the meshing of the third gear and the fourth gear provided on the output shaft.

  By transmitting the rotation decelerated by the parallel shaft gear reducer to the wheel by the wheel bearing, the wheel is rotationally driven by the rotation output of the electric motor.

JP 2017-65306 A

  By the way, in the in-wheel motor drive device disclosed by patent document 1, in order to improve the running stability and NVH characteristic of a vehicle, it is necessary to suppress the unsprung weight. Moreover, in order to accommodate a motor casing and a main body casing in the wheel space of a wheel, size reduction of an in-wheel motor drive device is calculated | required.

  On the other hand, in this type of in-wheel motor driving device, lubricating oil for cooling the electric motor and cooling and lubricating the parallel shaft gear reducer is enclosed in a casing. With this lubricating oil, the electric motor is cooled, and each gear is cooled and lubricated by splashing by the rotation of each gear of the parallel shaft gear reducer.

  In particular, it is necessary to supply abundant lubricating oil to the meshing portion between the first gear to which the rotation of the rotor of the electric motor is input and the second gear provided on the intermediate shaft. When the lubricating oil in the meshing portion of the first gear is insufficient, the gear tooth surface is deteriorated (peeling or seizing) at an early stage, and the durability of the first gear and the second gear may be reduced.

  Here, in the parallel shaft gear reducer, in order to reduce the size of the in-wheel motor drive device, the input shaft, the intermediate shaft, and the output shaft are offset with a layout as disclosed in Patent Document 1 ( (Refer FIG. 2 of patent document 1).

  Ideally, the lubricating oil should be supplied directly to the meshing portion of the first gear, but depending on the layout of the input shaft, intermediate shaft and output shaft, the lubricating oil can be supplied before the first gear meshes. However, the lubricating oil may be supplied only after the first gear is engaged.

  In order to reduce the size of the in-wheel motor drive device, the second gear, the third gear, and the fourth gear are disposed close to the first gear, so that the lubricating oil is supplied before the first gear meshes. In this case, piping or the like must be arranged in a narrow space before the first gear meshes.

  In addition, it is also effective to arrange a pump or the like in the in-wheel motor drive device and supply the shaft core from the input shaft to the meshing portion of the first gear. However, an oil passage must be formed in the input shaft and casing. This complicates the internal structure of the in-wheel motor drive device and increases the number of parts.

  Accordingly, the present invention has been proposed in view of the above-described problems, and the object of the present invention is to easily supply abundant lubricating oil to the meshing portion of the first gear and the second gear with a simple structure. It is in providing the vehicle drive device to obtain.

  A vehicle drive device according to the present invention includes an electric motor that drives a wheel, a speed reducer that decelerates and outputs the rotation of the electric motor, and a casing that houses the speed reducer. A first gear that is input and a second gear that meshes with the first gear.

  As a technical means for achieving the above-mentioned object, the present invention is arranged such that the first gear is arranged on the vehicle rear side of the second gear, and the upper portion of the meshing portion between the first gear and the second gear on the top surface of the casing. Further, the present invention is characterized in that a convex portion is formed which collects the lubricating oil adhering to the top surface of the casing and flows down to the meshing portion.

  In the present invention, the first gear to which the rotation of the electric motor is input is arranged on the vehicle rear side of the second gear, so that the lubricating oil scattered by the rotation of the first gear and the second gear is applied to the top surface of the casing. To reach. Lubricating oil adhering to the top surface of the casing is collected by the convex part formed in the upper part of the meshing part of the first gear and the second gear and flows down to the meshing part.

  Thus, by arranging the first gear on the vehicle rear side of the second gear, the lubricating oil can be supplied before the first gear and the second gear mesh. In addition, due to the simple structure of the convex portion, abundant lubricating oil can be supplied to the meshing portion between the first gear and the second gear.

  The convex portion in the present invention preferably has a structure in which an edge portion is provided at a portion corresponding to the center in the tooth width direction of the meshing portion to allow the lubricant flowing along the tooth width direction of the meshing portion to flow down to the meshing portion. .

  If such a structure is adopted, the lubricating oil flowing along the tooth width direction of the meshing portion of the convex portion is collected at the edge portion and flows down to the meshing portion. Thereby, the amount of lubricating oil supplied to the meshing portion between the first gear and the second gear can be increased.

  The speed reducer in the present invention has a fourth gear meshing with a third gear provided coaxially with the second gear, the first gear is disposed above the fourth gear, and a part of the fourth gear is A structure immersed in the lubricating oil stored in the bottom of the casing is desirable.

  If such a structure is employ | adopted, the lubricating oil stored in the bottom part of a casing will be scraped up by rotation of a 4th gear, and will reach the top | upper surface of a casing. The lubricating oil adhering to the top surface of the casing is collected by the convex portion and flows down to the meshing portion between the first gear and the second gear arranged above the fourth gear.

  In this way, not only the lubricating oil scattered by the rotation of the first gear and the second gear but also the lubricating oil scraped up by the rotation of the fourth gear is supplied to the meshing portion. Thereby, the amount of lubricating oil supplied to the meshing portion can be increased.

  In the present invention, the wall surfaces of the casings that are close to each other on the radially outer side of the first gear and the fourth gear are located radially outside the tangent line connecting the tooth tip circle of the first gear and the tooth tip circle of the fourth gear. A structure is desirable.

  By adopting such a structure, when the lubricating oil stored at the bottom of the casing is scraped up by the rotation of the fourth gear, the lubricating oil scattered toward the top surface of the casing is prevented from interfering with the wall surface of the casing. it can. As a result, the lubricating oil scraped up by the rotation of the fourth gear easily reaches the top surface of the casing.

  According to the present invention, by arranging the first gear on the vehicle rear side of the second gear, it is possible to supply the lubricating oil before the first gear and the second gear mesh. In addition, since the convex portion having a simple structure is formed on the top surface of the casing, abundant lubricating oil can be supplied to the meshing portion between the first gear and the second gear.

  In this way, with a simple structure, abundant lubricating oil can be supplied to the meshing portion of the first gear and the second gear, so the durability of the first gear and the second gear can be improved, and the reliability can be improved. A long-life vehicle drive device can be provided.

In embodiment of this invention, it is sectional drawing which shows the whole structure of an in-wheel motor drive device. It is sectional drawing which looked at the parallel shaft gear reducer (input shaft, intermediate shaft, and output shaft) of FIG. 1 from the wheel side. FIG. 3 is a partial enlarged cross-sectional view showing an example of the shape of the top surface of the casing with respect to the first gear, taken along the line P-P in FIG. 2. FIG. 6 is a partial enlarged cross-sectional view showing another example of the shape of the top surface of the casing with respect to the first gear, taken along the line P-P in FIG. 2. It is a top view which shows schematic structure of the electric vehicle carrying an in-wheel motor drive device. FIG. 6 is a rear sectional view showing the electric vehicle of FIG. 5.

  An in-wheel motor drive device will be described in detail with reference to the drawings as an embodiment of the present invention. FIG. 5 is a schematic plan view of the electric vehicle 11 on which the in-wheel motor drive device 21 is mounted, and FIG. 6 is a schematic cross-sectional view of the electric vehicle 11 as viewed from the rear.

  As shown in FIG. 5, the electric vehicle 11 includes a chassis 12, a front wheel 13 as a steering wheel, a rear wheel 14 as a driving wheel, and an in-wheel motor driving device 21 that transmits driving force to the rear wheel 14. Equip.

  As shown in FIG. 6, the rear wheel 14 is accommodated in a wheel housing 15 of the chassis 12, and is fixed to the lower portion of the chassis 12 via an independent suspension type suspension device (suspension) 16.

  The electric vehicle 11 includes an in-wheel motor drive device 21 that independently drives the left and right rear wheels 14 inside the wheel housing 15. This eliminates the need to provide a motor, a drive shaft, and a differential gear mechanism on the chassis 12.

  As a result, the electric vehicle 11 has an advantage that a large cabin space can be secured and the rotation of the left and right rear wheels 14 can be controlled independently.

  On the other hand, in the electric vehicle 11, it is necessary to suppress unsprung weight in order to improve running stability and NVH characteristics, and further, downsizing of the in-wheel motor drive device 21 is required in order to secure a wide cabin space. Yes.

  Therefore, the in-wheel motor drive device 21 of the embodiment shown in FIG. 1 has the following structure. Thereby, the compact in-wheel motor drive device 21 is implement | achieved and the electric vehicle 11 excellent in driving | running | working stability and NVH characteristic is obtained by suppressing unsprung weight.

  Before describing the characteristic configuration of this embodiment, the overall configuration of the in-wheel motor drive device 21 will be described. In the following description, with the in-wheel motor drive device 21 mounted on the vehicle body, the side closer to the outside of the vehicle body is referred to as the outboard side (left side in the drawing), and the side closer to the center is inboard side (right side in the drawing). Called.

  As shown in FIG. 1, the in-wheel motor drive device 21 includes an electric motor 22 that drives the rear wheel 14 (see FIGS. 5 and 6), and a parallel shaft gear reduction that decelerates and outputs the rotation of the electric motor 22. And a wheel bearing 24 for transmitting the output of the parallel shaft gear reducer 23 to the rear wheel 14 described above.

  In this embodiment, the radial gap type electric motor 22 is illustrated, but other electric motors such as an axial gap type may be used.

  The electric motor 22 and the parallel shaft gear reducer 23 are accommodated in the casing 25. The casing 25 in which the electric motor 22 and the parallel shaft gear reducer 23 are accommodated is mounted in the wheel housing 15 (see FIG. 6) of the electric vehicle 11.

  The electric motor 22 includes a stator 26 fixed to the casing 25, a rotor 27 disposed so as to face the inner side in the radial direction of the stator 26 with a gap, and a rotor 27 disposed on the inner side in the radial direction of the rotor 27 so as to rotate integrally with the rotor 27. And a motor rotating shaft 28.

  The motor rotating shaft 28 can rotate at a high speed of about 10,000 to 1000 rotations per minute. The stator 26 is configured by winding a coil around the outer periphery of the magnetic core. The rotor 27 has a permanent magnet or a magnetic body disposed therein.

  The motor rotating shaft 28 holds the rotor 27 by a holder portion 29 extending radially outward. The motor rotating shaft 28 is supported by the bearings 30 and 31 so as to be rotatable with respect to the casing 25.

  The parallel shaft gear reducer 23 includes an input shaft 32, an intermediate shaft 33, and an output shaft 34. The input shaft 32 is provided with a first gear 37. The intermediate shaft 33 is integrally provided with a large-diameter second gear 35 positioned on the inboard side and a small-diameter third gear 36 positioned on the outboard side. The output shaft 34 is provided with a fourth gear 38.

  In the parallel shaft gear reducer 23, the first gear 37 of the input shaft 32 and the second gear 35 of the intermediate shaft 33 are engaged, and the third gear 36 of the intermediate shaft 33 and the fourth gear 38 of the output shaft 34 are engaged. Thus, the rotation of the electric motor 22 is decelerated with a predetermined reduction ratio.

  Since the in-wheel motor drive device 21 is housed in the wheel housing 15 (see FIG. 6) and becomes an unsprung load, it is essential to reduce the size and weight.

  Therefore, by using the parallel shaft gear reducer 23 having a large reduction ratio, the electric motor 22 can be miniaturized by combining with the high-speed electric motor 22, and the in-wheel motor drive device 21 having a compact and high reduction ratio can be obtained. Can be realized.

  The input shaft 32 is coaxially attached to the motor rotating shaft 28 by spline fitting. The input shaft 32, the intermediate shaft 33, and the output shaft 34 are rotatably supported by the casing 25 by bearings 39 to 44. The output shaft 34 is coaxially attached to the hub wheel 46 of the wheel bearing 24 by spline fitting.

  FIG. 2 is a cross-sectional view of the input shaft 32, the intermediate shaft 33, and the output shaft 34 of the parallel shaft gear reducer 23 housed in the casing 25 as viewed from the outboard side. The rotation centers C1 to C3 of the input shaft 32, the intermediate shaft 33, and the output shaft 34 are offset with the layout shown in FIG.

  In this way, the input shaft 32, the intermediate shaft 33, and the output shaft 34 are offset to reduce the size of the parallel shaft gear reducer 27 in the axial direction and the radial direction.

  Here, helical gears are used for the first gear 37, the second gear 35, the third gear 36 and the fourth gear 38. Helical gears are effective in that the number of teeth engaged simultaneously increases and the tooth contact is dispersed, so that the sound is quiet and torque fluctuation is small.

  In this way, by using a helical gear as the parallel shaft gear reducer 23, it is possible to realize the in-wheel motor drive device 21 that is easy to manufacture and can be reduced in cost, and that is quiet and efficient in terms of performance. it can.

  The wheel bearing 24 includes an outer ring 45 fixed to the casing 25, a hub ring 46 disposed inside the outer ring 45, an inner ring 47 press-fitted into the hub ring 46, a hub ring 46, the inner ring 47, and the outer ring 45. The main part is composed of a plurality of rolling elements 48 arranged therebetween.

  A preload is applied to the wheel bearing 24 by crimping the end portion on the inboard side of the hub wheel 46. By applying this preload, the wheel bearing 24 has a double-row angular ball bearing structure.

  A shaft portion 50 extending integrally from the fourth gear 38 of the parallel shaft gear reducer 23 to the outboard side is coupled to the shaft hole 49 of the hub wheel 46 of the wheel bearing 24 so as to transmit torque by spline fitting. Yes.

  Seal members 51 are provided at both ends in the axial direction of the wheel bearing 24 to prevent intrusion of muddy water and the like and leakage of grease.

  A flange 52 is integrally formed on the outboard side of the hub wheel 46. The rear wheel 14 (see FIGS. 5 and 6) is connected to the flange 52 by a hub bolt (not shown).

  In the in-wheel motor drive device 21 having the above configuration, the rotation of the electric motor 22 is decelerated by the first gear 37, the second gear 35, the third gear 36, and the fourth gear 38 of the parallel shaft gear reducer 23, and the wheels Is transmitted to the bearing 24 for use.

  Since the rotation of the electric motor 22 is decelerated by the parallel shaft gear reducer 23 and transmitted to the wheel bearing 24, the rear wheel 14 (FIGS. 5 and 5) is used even when the low-torque high-speed electric motor 22 is employed. 6) can be transmitted.

  The overall configuration of the in-wheel motor drive device 21 in this embodiment is as described above, and the characteristic configuration will be described in detail below.

  In the in-wheel motor drive device 21, lubricating oil for cooling the electric motor 22 and cooling and lubricating the parallel shaft gear reducer 23 is enclosed in the internal space of the casing 25.

  In particular, as shown in FIG. 2, a part of the fourth gear 38 of the output shaft 34 is in an oil bath state in which the oil is constantly immersed in the lubricating oil 53, and the parallel shaft gear reducer is splashed by the rotation of the fourth gear 38. 23 is cooled and lubricated.

  In this way, by immersing only the fourth gear 38 having the slowest rotation speed, there is an effect of avoiding a reduction in the efficiency of the parallel shaft gear reducer 23 due to an increase in the stirring resistance of the lubricating oil 53.

  Here, in order to realize a lightweight and compact in-wheel motor drive device 21, as shown in FIG. 1, the first gear 37, the second gear 35, the third gear 36 and the fourth gear of the parallel shaft gear reducer 23 are used. 38 is arranged densely, and the radial gap and the axial gap between the parallel shaft gear reducer 23 and the casing 25 are made as small as possible.

  In this embodiment, as shown in FIG. 2, the first gear 37 of the input shaft 32 is arranged on the vehicle rear side of the second gear 35 of the intermediate shaft 33. Further, the convex portion for collecting the lubricating oil 53 adhering to the top surface 54 of the casing 25 and flowing down to the meshing portion 55 at a position above the meshing portion 55 of the first gear 37 and the second gear 35 on the top surface 54 of the casing 25. A portion 56 is formed.

  The lubricating oil 53 spattered by the centrifugal force of the first gear 37, the second gear 35, the third gear 36 and the fourth gear 38 rotates and reaches the top surface 54 of the casing 25. The lubricating oil 53 adhering to the top surface 54 of the casing 25 is collected by the convex portion 56 formed at the upper portion of the meshing portion 55 between the first gear 37 and the second gear 35 and flows down to the meshing portion 55.

  The convex portion 56 may be formed at the same time as the casing 25 is manufactured by casting. Moreover, the convex part 56 may be other than the shape shown in FIG. 2, and the shape is arbitrary.

  The first gear 37 of the input shaft 32 to which the rotation of the electric motor 22 is input via the motor rotation shaft 28 (see FIG. 1) is disposed on the vehicle rear side of the second gear 35 of the intermediate shaft 33. Thus, when the vehicle moves forward, lubrication occurs before the first gear 37 that rotates counterclockwise (see arrow A in FIG. 2) and the second gear 35 that rotates clockwise (see arrow B in FIG. 2) mesh with each other. Oil 53 can be supplied.

  In this way, by forming the convex portion 56 having a simple structure on the top surface 54 of the casing 25, the lubricating oil is caused to flow down from the convex portion 56 before the first gear 37 and the second gear 35 are engaged with each other. 53 can be supplied. As a result, abundant lubricating oil 53 can be supplied to the meshing portion 55 between the first gear 37 and the second gear 35.

  By supplying abundant lubricating oil 53 based on this simple structure, the gear tooth surface can be prevented from deteriorating (peeling or seizing), so the durability of the first gear 37 and the second gear 35 can be improved, A long-life in-wheel motor drive device 21 with high performance can be provided.

  Further, as shown in FIG. 3, in the convex portion 56, lubrication that flows along the tooth width direction of the meshing portion 55 at a portion corresponding to the center of the meshing portion 55 of the meshing portion 55 of the first gear 37. A bent portion 57 is provided as an edge portion for allowing oil to flow down to the meshing portion 55.

  The convex portion 56 of the top surface 54 of the casing 25 extends in a horizontal direction from the wall surface and has a shape inclined upward at a portion corresponding to the center of the meshing portion 55 of the first gear 37 in the tooth width direction. The bent portion 57 shown in FIG. 3 is formed at the boundary between the horizontal portion and the inclined portion.

  With this structure, the lubricating oil 53 that flows along the slanting convex portion 56 along the tooth width direction of the meshing portion 55 is collected in the bent portion 57 and flows down to the meshing portion 55. Thereby, the amount of lubricating oil supplied to the meshing portion 55 between the first gear 37 and the second gear 35 can be increased.

  The edge portion may have a structure as shown in FIG. 4 other than the bent portion 57 shown in FIG. In the structure shown in FIG. 4, the convex portion 56 of the top surface 54 of the casing 25 has a shape inclined upward from the wall surface. In the convex portion 56, a concave portion 58 as an edge portion is formed at a portion corresponding to the center in the tooth width direction of the meshing portion 55 of the first gear 37.

  With this structure, the lubricating oil 53 that flows along the slanting convex portion 56 along the tooth width direction of the meshing portion 55 is collected in the concave portion 58 and flows down to the meshing portion 55. Thereby, the amount of lubricating oil supplied to the meshing portion 55 between the first gear 37 and the second gear 35 can be increased.

  The parallel shaft gear reducer 23 of this embodiment includes a layout in which a first gear 37 is disposed above a fourth gear 38 immersed in a lubricating oil 53 stored in the bottom of the casing 25.

  With this structure, the lubricating oil 53 stored at the bottom of the casing 25 is scraped up by the rotation of the fourth gear 38 and reaches the top surface 54 of the casing 25. The lubricating oil 53 adhering to the top surface 54 of the casing 25 is collected on the convex portion 56 of the top surface 54 of the casing 25 and flows down to the meshing portion 55 of the first gear 37.

  Thus, not only the lubricating oil 53 scattered by the rotation of the first gear 37 and the second gear 35, but also the lubricating oil 53 scraped up by the rotation of the third gear 36 and the fourth gear 38 is also the first gear 37. Is supplied to the meshing portion 55. Thereby, the amount of lubricating oil supplied to the meshing part 55 of the first gear 37 can be increased.

  In the layout in which the first gear 37 is arranged above the fourth gear 38, as shown in FIG. 2, the wall surface 59 of the casing 25 that is close to the first gear 37 and the fourth gear 38 on the radially outer side is the first gear 37. It is located radially outside the tangent L connecting the tooth tip circle of the gear 37 and the tooth tip circle of the fourth gear 38.

  That is, the wall surface 59 of the casing 25 is not interposed in the space between the first gear 37 and the fourth gear 38. Therefore, when the lubricating oil 53 stored at the bottom of the casing 25 is scraped up by the rotation of the fourth gear 38, the lubricating oil 53 scattered toward the top surface 54 of the casing 25 interferes with the wall surface 59 of the casing 25. This can be suppressed.

  As a result, the lubricating oil 53 scraped up by the rotation of the fourth gear 38 easily reaches the top surface 54 of the casing 25. The lubricating oil 53 adhering to the top surface 54 of the casing 25 is collected on the convex portion 56 of the top surface 54 of the casing 25 and flows down to the meshing portion 55 of the first gear 37.

  In the above embodiment, the case where the convex portion 56 is provided immediately above the meshing portion 55 between the first gear 37 and the second gear 35 is illustrated, but the third gear 36 and the portion above the meshing portion 55 are provided. A convex portion different from the convex portion 56 described above may be provided near the meshing portion of the fourth gear 38, and the number of convex portions is arbitrary.

  In this way, by providing a convex portion near the meshing portion of the third gear 36 and the fourth gear 38 above the meshing portion 55 of the first gear 37 and the second gear 35, the top surface 54 of the casing 25 is provided. It is also possible to supply the adhering lubricating oil to the meshing portion between the third gear 36 and the fourth gear 38.

  In the above embodiment, the vehicle drive device in which the in-wheel motor drive device 21 for driving the left and right rear wheels 14 is provided inside the wheel housing 15 (see FIG. 6) has been described. However, the present invention is limited to this. The present invention can also be applied to a vehicle drive device called an on-board type.

  In this on-board type vehicle drive device, two sets of an electric motor 22 and a parallel shaft gear reducer 23 are attached to the vehicle body, and the output of the parallel shaft gear reducer 23 is transmitted to the rear wheels 14 via the left and right drive shafts. The structure which comprises.

  Alternatively, a structure is provided in which a set of electric motor 22 and parallel shaft gear reducer 23 is attached, the output of parallel shaft gear reducer 23 is distributed to the left and right with a differential gear, and transmitted to rear wheel 14 via a drive shaft.

  Further, in the above embodiment, as shown in FIGS. 5 and 6, the electric vehicle 11 having the rear wheel 14 as the driving wheel is illustrated, but the front wheel 13 may be the driving wheel, and the vehicle is a four-wheel driving vehicle. Also good. In the present specification, “electric vehicle” is a concept including all vehicles that obtain driving force from electric power, and includes, for example, a hybrid vehicle.

  The present invention is not limited to the above-described embodiments, and can of course be implemented in various forms without departing from the gist of the present invention. It includes the equivalent meanings recited in the claims and the equivalents recited in the claims, and all modifications within the scope.

21 Vehicle drive device (in-wheel motor drive device)
22 Electric motor 23 Reducer (Parallel shaft gear reducer)
25 casing 35 second gear 36 third gear 37 first gear 38 fourth gear 53 lubricating oil 54 top surface 55 meshing portion 56 convex portion 57 edge portion (bending portion)
58 Edge (recess)
59 Wall

Claims (4)

A vehicle drive device comprising: an electric motor that drives a wheel; a speed reducer that decelerates and outputs rotation of the electric motor; and a casing that houses the speed reducer,
The speed reducer has a first gear to which rotation of an electric motor is input, and a second gear meshing with the first gear, and the first gear is disposed on the vehicle rear side of the second gear,
A convex portion is formed on the top surface of the casing at the upper portion of the meshing portion between the first gear and the second gear to collect the lubricating oil adhering to the top surface of the casing and flow down to the meshing portion. Vehicle drive device.   The convex portion has a structure in which an edge portion is provided at a portion corresponding to the center in the tooth width direction of the meshing portion to allow the lubricant flowing along the tooth width direction of the meshing portion to flow down to the meshing portion. Item 4. The vehicle drive device according to Item 1.   The speed reducer has a fourth gear meshing with a third gear provided coaxially with the second gear, and the first gear is disposed above the fourth gear and is a part of the fourth gear. The vehicle drive device according to claim 1, wherein the vehicle is immersed in a lubricating oil stored in a bottom portion of the casing.   The wall surface of the casing adjacent to the first gear and the fourth gear on the radially outer side is located on the radially outer side with respect to the tangent line connecting the tooth tip circle of the first gear and the tooth tip circle of the fourth gear. The vehicle drive device according to claim 3.

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