JP2019059391A - In-wheel motor drive device - Google Patents

Abstract

To provide an in-wheel motor drive device which can properly cool and lubricate a drive part.SOLUTION: An in-wheel motor drive device 10 includes: a drive part 20 having an electric motor 21; and a housing 11 which houses the drive part 20. The housing 11 is provided with: an attachment part 12 of a ball joint 6 for rotatably connecting a lower arm 3 to a bottom part of the housing 11; and an oil storage part 13 which stores a lubrication oil 14 to be supplied to the drive part 20 during driving. The oil storage part 13 is disposed at a position shifted from the attachment part 12 in a vehicle fore and aft direction (the vehicle front side) and is provided so as to overlap with the attachment part 12 when viewed in the vehicle fore and aft direction.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an in-wheel motor drive device.

  For example, Patent Document 1 below includes a drive unit having an electric motor, a wheel bearing for transmitting the output of the drive unit to a wheel, and a housing for accommodating the drive unit and supporting the wheel bearing, An in-wheel motor drive is disclosed in which the center of rotation of the motor and the center of rotation of the wheel bearing are offset. The in-wheel motor drive is arranged such that the entire device is disposed inside the wheel by connecting the housing to a suspension having a strut as a suspension part and a lower arm. The strut is pivotably connected to the top of the housing via a bracket, and the end in the vehicle width direction outer end of the lower arm is pivotably connected to the bottom of the housing via a ball joint.

  In the in-wheel motor drive device of patent document 1, the oil storage part (oil storage space) for storing lubricating oil which should be supplied to a drive part is provided in the housing. The lubricating oil stored in the oil storage section is supplied to the drive section by a lubrication mechanism provided with an oil pump and an oil supply path during driving of the in-wheel motor drive apparatus to cool and lubricate the drive section.

JP, 2015-214273, A

  By the way, especially when mounting an in-wheel motor drive device in a large sized vehicle, a high torque in-wheel motor drive device is needed. In order to realize a high torque and highly reliable in-wheel motor drive, for example, a large electric motor is employed, and the volume of the oil reservoir is increased to enable appropriate cooling of the large electric motor. It is necessary to take measures to cause the enlargement of the housing such as. However, since the in-wheel motor drive is disposed in the wheel, the radial enlargement of the housing is limited by the wheel size. Therefore, in order to realize a high torque in-wheel motor drive device, the housing may have to be enlarged in the vehicle width direction.

  By enlarging the housing in the vehicle width direction, the entire housing can not be accommodated inside the wheel, and when a part of the housing in the vehicle width direction protrudes outside the wheel (in the vehicle width direction), At the time of driving, flying objects such as pebbles thrown up are likely to collide with the bottom of the housing. At this time, if the oil storage portion (oil storage space) is defined by the entire bottom portion of the housing provided over a wide range as in Patent Document 1, oil leakage due to collision of flying objects on the housing bottom portion Is apt to occur.

  In view of the above-described circumstances, the present invention appropriately cools and lubricates the drive unit housed in the housing even when it is necessary to project a part of the housing inward in the vehicle width direction of the wheel. It is a main object to provide an in-wheel motor drive that can

  The present invention invented to achieve the above object comprises a drive unit having an electric motor, a bearing for a wheel, and a housing accommodating the drive unit and supporting the bearing for a wheel, and the lower arm is mounted on the housing. A mounting portion to which a ball joint for rotatably connecting to a bottom portion of the housing is mounted, and an oil storage portion for storing lubricating oil to be supplied to a driving portion being driven are provided. In the in-wheel motor drive apparatus in which the rotation center and the rotation center of the wheel bearing are offset, the oil storage portion is disposed at a position shifted in the vehicle longitudinal direction with respect to the mounting portion when viewed from the vehicle longitudinal direction The mounting portion is provided so as to overlap.

  As described above, if the oil storage unit is disposed at a position shifted in the vehicle longitudinal direction (front or rear side of the vehicle) with respect to the ball joint mounting unit, driving of the vehicle equipped with the in-wheel motor drive device The risk of oil leakage can be reduced as much as possible because flying objects such as pebbles splashed up during traveling are less likely to collide with the housing (the defining portion of the oil storage portion of the housing). Further, since the oil storage portion is provided so as to overlap the mounting portion of the ball joint when the oil storage portion is viewed from the longitudinal direction of the vehicle, the volume of the oil storage portion can be sufficiently secured. Therefore, even when a large electric motor is employed, the oil storage section can store lubricating oil of a necessary and sufficient amount for appropriately cooling and lubricating the drive section including the electric motor.

  The lower arm is pivotably connected to the bottom of the housing via a ball joint, so that, for example, when the wheel bounces and rebounds in the form of following the unevenness of the road surface, the bottom of the housing There is a possibility that the lower arm may interfere with the forming portion). Such a problem can be prevented as much as possible, for example, by curving the lower arm downward, but another problem arises that the minimum ground clearance of the vehicle is lowered.

  So, in this invention, the 1st inclination part which shifted to the upper side of a vehicle gradually toward the vehicle width direction inner side from the vehicle width direction outer side is provided in the bottom part of an oil storage part. In this way, interference between the housing (oil storage portion) and the lower arm at the time of the wheel rebound can be avoided without taking measures such as bending the lower arm downward. In addition, if the above configuration is adopted, the lubricating oil stored in the oil storage portion is less likely to be unevenly distributed in the vehicle width direction inner region of the oil storage portion. For this reason, for example, in the case where an oil pipe inlet port for supplying lubricating oil to the drive section is opened in the oil reservoir section, the inlet port can be disposed in the vehicle width direction outer region of the oil reservoir section. For example, the possibility that the suction port is exposed to the atmosphere when the vehicle turns or the like can be reduced as much as possible. Thus, the lubricating oil can be stably supplied to the drive unit even when the vehicle turns.

  The bottom of the oil storage portion may be provided with a second inclined portion which is gradually shifted upward of the vehicle as the distance between the front and rear of the vehicle from the suction port of the oil pipe opened in the oil storage portion increases. In this way, the possibility that the suction port is exposed to the atmosphere during acceleration or deceleration of the vehicle can be reduced as much as possible.

  In the above configuration, the drive unit may further include a reduction gear that decelerates and outputs the rotation of the electric motor. As this reduction gear, a parallel shaft gear reduction gear having a plurality of gears (gear shafts) whose rotation center axes are arranged in parallel to each other can be adopted.

  From the above, according to the present invention, in the in-wheel motor drive device in which the parallel shaft gear reducer is applied to the reducer, the parallel shaft gear reducer is configured without causing increase in size and complexity of the entire device. It becomes possible to efficiently lubricate and cool the meshing portion of the gears. This makes it possible to realize a lightweight, compact, highly reliable in-wheel motor drive device.

It is the schematic when the suspension structure of the left front wheel of the vehicle in which the in-wheel motor drive device which concerns on embodiment of this invention was integrated is seen from the vehicle rear side. It is a schematic front view of an in-wheel motor drive device. It is an AA line arrow schematic sectional view of FIG. It is a B-C-D line schematic sectional drawing of FIG. It is a schematic diagram near the housing bottom part at the time of driving run of vehicles.

  Hereinafter, embodiments of the present invention will be described based on the drawings.

  FIG. 1 is a schematic view of a suspension structure of a left front wheel of a vehicle (for example, an electric vehicle) incorporating the in-wheel motor drive device 10 according to the embodiment of the present invention as viewed from the rear side of the vehicle. The in-wheel motor drive device 10 is connected to the chassis 4 via a suspension device 1 provided with struts 2 and lower arms (for example, A-type lower arms) 3 as suspension arms. The upper end (end on the vehicle upper side) of the strut 2 is rotatably connected to the chassis 4, and the lower end (end on the vehicle lower side) of the strut 2 is a housing of the in-wheel motor drive 10 It is rotatably connected to a knuckle 5 provided at 11. The end of the lower arm 3 inside in the vehicle width direction (hereinafter also referred to as “inboard side”) is rotatably connected to the chassis 4, and the outside in the vehicle width direction of lower arm 3 (hereinafter also referred to as “outboard side”) The end of) is rotatably connected to the bottom of the housing 11 of the in-wheel motor drive 10 through a ball joint 6 (see FIG. 2).

  The suspension system 1 described above is a strut type, which is a kind of independent suspension system, but the in-wheel motor drive system 10 has a chassis 4 via a suspension system adopting a double wishbone system or other suspension system. It is also possible to connect. Since the strut type suspension device 1 also functions as the upper arm, the strut type suspension device 1 is characterized in that it is lighter, more compact and less expensive than a so-called double wishbone type in which the upper arm is an essential component.

  A kingpin axis (a virtual center of rotation of the front wheel at the time of steering operation, defined by a straight line connecting a rotation center of the upper end of the strut 2 and a rotation center (ball joint 6) of an end on the outboard side of the lower arm 3 The king pin axis) K is inclined at a predetermined angle with respect to the vertical direction (vertical direction) of the vehicle such that the upper portion thereof is positioned inward in the vehicle width direction than the lower portion. The kingpin offset defined by the distance between the road intersection point of the extension line of the kingpin axis K and the contact center of the wheel (front wheel) usually decreases the steering operability and the straight running stability of the vehicle as this increases. Therefore, the ball joint 6 is attached to the end (near the end) on the outboard side of the bottom of the housing 11.

  2 is a schematic front view of the in-wheel motor drive device 10 (a view from the left side of the in-wheel motor drive device 10 shown in FIG. 1), and FIG. 3 is a schematic cross-sectional view taken along line AA of FIG. 2 is a schematic cross-sectional view taken along the line B-C-D of FIG. As shown in FIGS. 2 to 4, the in-wheel motor drive device 10 accommodates a drive unit 20 that generates a drive force, a wheel bearing 40 that transmits the output of the drive unit 20 to the front wheels, and the drive unit 20. And the housing 11 to which the wheel bearing 40 is attached. The drive unit 20 of the present embodiment includes the electric motor 21 and the reduction gear 30 that decelerates the rotation of the electric motor 21 and outputs the same to the wheel bearing 40, and the rotation centers of the electric motor 21 and the wheel bearing 40 are mutually different. They are arranged at different positions (offset arrangement).

  As shown in FIG. 3, the electric motor 21 has a stator 22 fixed to the housing 11, a rotor 23 opposed to the inner diameter side of the stator 22 with a radial gap therebetween, and a motor having the rotor 23 mounted on the outer periphery It is a radial gap type provided with a rotating shaft 24. The motor rotation shaft 24 is rotatable at a rotational speed of about 1 / several thousand times per minute, and is rotatably supported relative to the housing 11 by the rolling bearings 25 and 26 disposed at two places separated in the axial direction thereof. It is done. As the electric motor 21, in place of the radial gap type, an axial gap type in which the stator 22 and the rotor 23 are disposed to face each other with a gap in the axial direction may be employed.

  The reduction gear 30 has a plurality of gears, and is configured by a so-called parallel shaft gear reduction gear in which the rotation centers of the respective gears are offset (the rotation center axes of the respective gears are arranged parallel to each other). The reduction gear 30 of this embodiment is disposed coaxially with the motor rotation shaft 24 and coaxially with the input gear 31 connected integrally with the motor rotation shaft 24 so as to be rotatable integrally with the rotation of the wheel bearing 40 Three-shaft type equipped with an output gear 33 connected integrally rotatably with the input side (hub wheel 41) of the bearing 40 and an intermediate gear 32 disposed between the input gear 31 and the output gear 33 . The intermediate gear 32 has a large diameter gear portion 32 a meshing with the input gear 31 and a small diameter gear portion 32 b meshing with the output gear 33. The number of teeth of the large diameter gear portion 32a of the intermediate gear 32 is larger than the number of teeth of the small diameter gear portion 32b of the input gear 31 and the intermediate gear 32, and the number of teeth of the output gear 33 is the same as that of the small diameter gear portion 32b of the intermediate gear 32. More than the number of teeth. From the above configuration, the reduction gear 30 of the present embodiment reduces the rotation of the motor rotation shaft 24 in two steps and transmits it to the wheel bearing 40.

  Although detailed illustration is omitted, it is preferable to use a so-called helical gear for each of the gears 31 to 33 constituting the reduction gear 30. The helical gear has an advantage that the noise at the time of meshing is quiet and the torque fluctuation is small because the number of teeth meshing simultaneously and the tooth contact is dispersed. Therefore, the use of the helical gear is advantageous in realizing the reducer 30 which is quiet and excellent in torque transmission efficiency.

  As shown in FIG. 4, the wheel bearing 40 is a so-called inner ring rotation type wheel bearing. The wheel bearing 40 is a double-row angular contact ball bearing provided with an inward member 43 including a hub wheel 41 and an inner ring 42, an outer ring 44, a plurality of balls 47, and a cage not shown. Although detailed illustration is omitted, the internal space of the wheel bearing 40 is filled with grease as a lubricant. Seal members are provided at both axial ends of the wheel bearing 40 in order to prevent foreign matter from entering the bearing internal space and grease leakage to the outside of the bearing.

  The hub wheel 41 is integrally rotatably connected to the shaft portion of the output gear 33 by spline fitting. A flange portion 41a (see FIG. 2) is provided on an outer periphery of an end portion of the hub wheel 41 on the outboard side, and a brake disc and a wheel of a front wheel are attached to the flange portion 41a. At the inboard end of the hub wheel 41, a crimped portion 41b formed by crimping and fixing the inner ring 42 is formed. The crimped portion 41 b applies a preload to the wheel bearing 40.

  An inner raceway surface 45 on the outboard side is formed on the outer periphery of the hub wheel 41, and an inner raceway surface 45 on the inboard side is formed on the outer periphery of the inner ring 42. On the inner periphery of the outer ring 44, a double-row outer raceway 46 corresponding to both inner raceways 45, 45 is formed, and a ball track formed by a pair of the inner raceway 45 and the outer raceway 46 A plurality of balls 47 are incorporated in the. The outer ring 44 integrally includes a flange portion 44a extending radially outward from an end portion on the outboard side, and the housing 48 is positioned relative to the outer ring 44 by the flange portion 44a and the snap ring 49. It is bolted to 11.

  As shown in FIGS. 3 and 4, the housing 11 includes a cylindrical member 11A, and a first cover member 11B and a second cover member 11C that close the openings on the outboard side and the inboard side of the cylindrical member 11A, respectively. , And these three members 11A to 11C are connected using bolt members not shown. As shown in FIG. 2, the housing 11 (first cover member 11B) is integrally provided with a mounting portion 12 to which the ball joint 6 is mounted. The mounting portion 12 is provided near the end on the outboard side of the bottom of the housing 11 for the reason described above (see FIG. 3).

  In the in-wheel motor drive device 10 having the above configuration, when an alternating current is supplied to the stator 22 of the electric motor 21 and an electromagnetic force is generated, the rotor 23 and the motor rotation shaft 24 rotate. The rotation of the motor rotation shaft 24 is reduced by the reduction gear 30 and transmitted to the wheel bearing 40. Therefore, even when the low torque and high-speed rotation type electric motor 21 is adopted, it is possible to transmit the torque necessary for rotating the front wheel at a predetermined speed.

  As shown in FIGS. 2 to 4, the in-wheel motor drive device 10 further includes a lubrication mechanism 50 for repeatedly (continuously) supplying the lubricating oil 14 to the drive unit 20 being driven.

  The lubrication mechanism 50 includes an oil pump 51 and an oil pipe 52, and an oil reservoir 13 which is provided in the housing 11 and stores the lubricating oil 14 to be supplied to the drive unit 20 via the oil pump 51 and the oil pipe 52. In the present embodiment, the bottom side region of the internal space of the housing 11 functions as the oil storage portion 13.

  The oil pump 51 is disposed adjacent to the inboard side of the output gear 33 of the reduction gear 30. Here, the oil pump 51 is configured to perform suction and discharge operations of the lubricating oil 14 as the output gear 33 rotates. used.

  The oil pipe 52 includes a suction pipe 53 extending from the suction port of the oil pump 51 to (the internal space of) the oil reservoir 13 and a supply pipe 54 extending from the discharge port of the oil pump 51. As shown in FIGS. 2 and 3, the suction port of the suction pipe 53 is disposed so as to open at the deepest portion (here, near the end portion on the outboard side) of the oil storage portion 13.

  As shown in FIG. 4, the supply piping 54 mainly extends in the vehicle width direction on the lower side of the electric motor 21, and an end opening on the outboard side is disposed close to the discharge port of the oil pump 51. A supply pipe 55, and an oil passage 56 provided inside the second cover member 11C constituting the housing 11 and extending in the vertical direction and having a lower end connected to the inboard end opening of the first supply pipe 55; A second supply pipe 57 is disposed on the upper side of the electric motor 21 and extends in the vehicle width direction, and an end opening on the inboard side is connected to the upper end of the oil passage 56. As shown in FIG. 2, the supply pipe 54 ends at a position substantially immediately above the input gear 31. That is, the end on the outboard side of the second supply pipe 57 is disposed substantially directly above the input gear 31. Then, when the lubricating oil 14 is discharged from the discharge port of the oil pump 51 by the oil pump 51 performing suction and discharging operations of the lubricating oil 14 with the rotation of the output gear 33, the lubricating oil 14 is supplied. The electric motor 21 and the reduction gear 30 are supplied via the pipe 54 (the flow of the lubricating oil 14 is referred to the white arrow in FIG. 4).

  More specifically, the second supply pipe 57 is provided with a discharge port 57a opened to the inner and outer diameter surfaces, and the lubricating oil 14 discharged (dropped) from the discharge port 57a is the upper end of the electric motor 21. It is supplied to the department. The lubricating oil 14 supplied to the upper end portion of the electric motor 21 cools the stator 22 and the rotor 23 while moving downward under the influence of gravity, and finally falls into the oil reservoir 13 and is recovered. . In addition, when the lubricating oil 14 is discharged from the end opening 57 b on the outboard side of the second supply pipe 57 (the end opening of the supply pipe 54), the lubricating oil 14 is transferred to the input gear 31 of the reduction gear 30. After being supplied (see FIG. 2), the input gear 31 (the meshing portion between the input gear 31 and the large diameter gear portion 32a of the intermediate gear 32) is lubricated and cooled, and then dropped into the oil reservoir 13 and recovered.

  In the present embodiment, lubrication and cooling of the output gear 33 are carried out by immersing the lower portion of the output gear 33 in the lubricating oil 14 stored in the oil reservoir 13 as shown in FIG. Lubrication and cooling 32 are performed by scraping (splashing) the lubricating oil 14 stored in the oil reservoir 13 with the rotation of the output gear 33. For this reason, the oil storage portion 13 provided in the housing 11 is formed such that the lubricating oil 14 stored therein can be in contact (always) with a part of the output gear 33. Therefore, the upper end portion of the oil storage portion 13 is located above the lower end portion of the output gear 33.

  As shown in FIG. 2, the oil storage portion 13 is disposed at a position shifted with respect to the mounting portion 12 of the ball joint 6 provided in the housing 11 in the vehicle longitudinal direction (the vehicle front side in the present embodiment). This makes it difficult for flying objects such as pebbles splashed up during driving of a vehicle equipped with an in-wheel motor to hardly collide with the housing 11 (the defining portion of the oil storage portion 13 of the housing 11). The risk of oil leakage due to damage can be reduced as much as possible. In particular, if the oil storage portion 13 is disposed at a position shifted to the vehicle front side with respect to the mounting portion 12 of the ball joint 6 as in the present embodiment, a position shifted to the vehicle rear side with respect to the mounting portion 12 As compared with the case where the oil storage portion 13 is disposed, the possibility of the impact of an impact on the defining portion of the oil storage portion 13 of the housing 11 can be reduced, which is advantageous in reducing the risk of oil leakage.

  Further, as schematically shown in FIG. 3, the oil storage portion 13 is provided so as to overlap the mounting portion 12 of the ball joint 6 when the oil storage portion 13 is viewed from the longitudinal direction of the vehicle. That is, the lower end of the oil storage portion 13 is positioned lower than the lower end of the mounting portion 12, the upper end of the oil storage portion 13 is positioned upper than the upper end of the mounting portion 12, and the end of the oil storage portion 13 on the outboard side is The inboard end of the oil reservoir 13 is positioned more inboard than the inboard end of the mounting portion 12 than the outboard end of the mounting portion 12 . Thereby, the volume of oil storage part 13 can be secured sufficiently. Therefore, even when the large-sized electric motor 21 is employed, the oil storage portion 13 can store a sufficient amount of lubricating oil 14 for adequately cooling and lubricating the drive portion 20 including the electric motor 21. it can.

  Further, as shown in FIG. 3, the bottom of the oil reservoir 13 is provided with an inclined portion (first inclined portion) 15 which is gradually shifted upward from the outboard side to the inboard side. In this way, interference between the housing 11 and the lower arm 3 at the time of bounding and rebounding of the front wheel can be avoided without taking measures to bend the lower arm 3 downward (see FIG. 5). In this case, there is also an advantage that it is possible to prevent the occurrence of an adverse effect that the minimum ground height of the vehicle caused by curving the lower arm 3 downward becomes low.

  In addition, if the first inclined portion 15 is provided at the bottom of the oil storage portion 13, the suction port of the oil pipe 52 is arranged to open at the deepest portion (near the end portion on the outboard side) of the oil storage portion 53. The possibility of the oil inlet being exposed to the atmosphere can be reduced as much as possible when the vehicle is turning, etc. (see FIG. 5). Thus, the lubricating oil 14 can be stably supplied to the drive unit 20 even when the vehicle turns.

  Further, as shown in FIG. 2, the bottom of the oil storage portion 13 is provided with a second inclined portion 16 gradually shifted to the upper side of the vehicle as the distance from the oil inlet to the vehicle in the vehicle longitudinal direction increases. In the present embodiment, the second inclined portion 16 is provided on both the vehicle front side and the rear side of the oil suction port. In this way, even if the oil surface of the lubricating oil 14 stored in the oil storage unit 13 is inclined with respect to the longitudinal direction of the vehicle as the vehicle accelerates or decelerates, the oil inlet may be exposed to the atmosphere. Can be reduced. Therefore, the lubricating oil 14 can be stably supplied to the drive unit 20 also at the time of acceleration and deceleration of the vehicle.

  Although the second inclined portion 16 may be provided only on either the front side or the rear side of the oil suction port, in such a case, the oil suction port is exposed to the atmosphere during acceleration or deceleration of the vehicle. You are more likely to Therefore, as in the present embodiment, it is preferable to provide the second inclined portion 16 on both the vehicle front side and the rear side of the oil suction port.

  The in-wheel motor drive device 10 according to the present embodiment can properly cool and lubricate the drive unit 20 housed in the housing 11 and has high reliability because of the effects described above. It has the features.

  As mentioned above, although in-wheel motor drive 10 concerning one embodiment of the present invention was explained, an embodiment of the present invention is not restricted to this.

  For example, in the embodiment described above, as the oil pump 51 constituting the lubrication mechanism 50, suction of the lubricating oil 14 (using the rotation of the output gear 33) along with the rotation of the output gear 33 of the reduction gear 30 Although the type which performs discharge operation was adopted, as oil pump 51, you may adopt other types, such as an electric oil pump, for example. Further, although the oil pump 51 is disposed in the internal space of the housing 11 in the embodiment described above, the oil pump 51 may be disposed outside the housing 11.

  In the embodiment described above, the lubricating mechanism 50 substantially supplies only the input gear 31 (the meshing portion between the input gear 31 and the large diameter gear portion 32 a of the intermediate gear 32) of the reduction gear 30 by the lubrication mechanism 50. However, if there is no problem in the arrangement of the oil piping 52 (especially the supply piping 54) in the housing 11, the intermediate gear 32 and the output gear 33 The lubricating oil 14 can also be supplied to at least one of them.

  In the embodiment described above, the bottom of the oil reservoir 13 is constituted by the flat portion extending along the vehicle width direction and the vehicle front-rear direction, and the first inclined portion 15 and the second inclined portion 16. The bottom of the oil reservoir 13 can also be configured with only the first inclined portion 15 and the second inclined portion 16 (not shown).

  In the embodiment described above, the reduction gear (parallel shaft gear reduction gear) 30 is used to reduce the rotation of the motor rotation shaft 24 in two steps and transmit it to the wheel bearing 40. The rotation of the motor rotation shaft 24 may be decelerated in three or more steps and transmitted to the wheel bearing 40. Furthermore, although the case where the in-wheel motor drive device 10 is used in front wheels of a vehicle is described above, it is also possible to use the in-wheel motor drive device 10 in rear wheels of the vehicle.

  The present invention is not limited to the embodiment described above, and may be embodied in various forms without departing from the scope of the present invention. That is, the scope of the present invention is indicated by the claims, and further includes the equivalent meaning described in the claims and all the modifications within the scope.

Reference Signs List 1 suspension device 3 lower arm 6 ball joint 10 in-wheel motor drive 11 housing 12 (ball joint) mounting portion 13 oil reservoir 14 lubricating oil 15 first inclined portion 16 second inclined portion 20 driving portion 21 electric motor 30 reduction gear 40 Wheel bearing 50 Lubrication mechanism 51 Oil pump 52 Oil piping 53 Intake piping 54 Supply piping K King pin shaft

Claims (4)

A drive unit having an electric motor, a wheel bearing unit, and a housing accommodating the drive unit and supporting the wheel bearing unit, wherein the lower arm can be rotated relative to the bottom of the housing A mounting portion on which a ball joint for connecting to the driving portion is mounted, and an oil storage portion for storing lubricating oil to be supplied to the drive unit being driven, the rotation center of the electric motor and the wheel bearing In the in-wheel motor drive device in which the rotational center of the unit is offset and
The oil storage portion is disposed at a position shifted in the vehicle longitudinal direction with respect to the mounting portion, and is provided to overlap the mounting portion when viewed from the vehicle longitudinal direction. Wheel motor drive.   The in-wheel motor drive according to claim 1 provided with the 1st slope which shifted to the upper part side of the vehicle gradually towards the inner side of the cross direction from the cross direction outside to the bottom of said oil storage part.   The bottom portion of the oil storage portion is provided with a second inclined portion which is gradually shifted upward of the vehicle as the separation distance in the vehicle longitudinal direction from the suction port of the oil pipe opened in the oil storage portion increases. Or in-wheel motor drive according to 2. The drive unit further includes a reduction gear that decelerates and outputs the rotation of the electric motor,
The in-wheel motor drive according to any one of claims 1 to 3, wherein the reduction gear is a parallel-shaft gear reduction gear having a plurality of gears whose rotation center axes are arranged parallel to each other.

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