JP2013096541A - Lubrication mechanism for vehicular drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubrication mechanism for a vehicular drive device which can suppress shortage of lubrication of a bearing supporting a first revolving shaft while a vehicle runs.SOLUTION: A lower end 88 of a connecting port between a first space 84 and a second space 86 is formed at a higher position, in the perpendicular direction, than an inner circumferential lower end of an outer ring 47b of a bearing 47. As a result, even while a vehicle runs, a lubricating oil is stored to the same height as the lower end 88 of the connecting port, in a lower part of the first space 84. Since the lower end 88 of the connecting port is positioned higher, in the perpendicular direction, than the inner circumferential lower end of the outer ring 47b of the bearing 47, at least a part of a ball 47c constituting the bearing 47 is immersed in the stored lubricating oil and shortage of lubrication of the bearing 47 is suppressed.

Description

  The present invention relates to a lubrication mechanism for a vehicle drive device, and relates to a structure that suppresses insufficient lubrication.

  A first space surrounded by a first rotating shaft in which a first gear is formed and a case that houses a bearing that rotatably supports the first rotating shaft, and a second gear that meshes with the first gear are formed. There is known a vehicle drive device including a second space surrounded by the case that houses the second rotating shaft. This is the electric drive device for a vehicle disclosed in Patent Document 1. In the vehicle electric drive device of Patent Document 1, the output shaft 30 (first rotation shaft) of the electric motor 22 in which the counter drive gear 48 (first gear) is formed and the bearing 46 that rotatably supports the output shaft 30. A counter shaft 32 (second rotating shaft) is formed in which a first space surrounded by a transaxle case 44 (case) that houses the counter drive gear 48 and a counter driven gear 50 (second gear) that meshes with the counter drive gear 48 are housed. And a second space surrounded by the transaxle case 44.

JP 2010-223376 A

  By the way, in the vehicle electric drive device of Patent Document 1, the counter drive gear 48 has a smaller outer diameter than the counter driven gear 50 meshing with the counter drive gear 48 and is separated from the bottom surface of the case. Therefore, when the lubricating oil stored in the bottom of the transaxle case 44 is scraped up by the counter driven gear 50 or the like during traveling, and the oil level of the lubricating oil stored in the bottom of the transaxle case 44 decreases, The bearing 46 that rotatably supports the output shaft 30 in which the counter drive gear 48 is formed may be insufficiently lubricated.

  The present invention has been made against the background of the above circumstances, and its object is to rotatably support the first gear and one end side of the first rotating shaft on which the first gear is formed. A vehicle drive comprising: a first space surrounded by a case for housing a bearing; and a second space surrounded by the case for housing a second rotating shaft in which a second gear meshing with the first gear is formed. An object of the present invention is to provide a lubrication mechanism for a vehicle drive device that can suppress insufficient lubrication of a bearing that supports a first rotating shaft on which a first gear is formed even during traveling of the vehicle.

  In order to achieve the above object, the gist of the invention according to the first invention is that (a) the first gear and one end side of the first rotating shaft on which the first gear is formed are rotatably supported. A vehicle drive comprising: a first space formed by a case for housing a bearing; and a second space formed by the case for housing a second rotating shaft in which a second gear meshing with the first gear is formed. (B) a lower end of a connection port between the first space and the second space is positioned higher than a lower end of an inner periphery of the outer ring of the bearing in a vertical direction. .

  In this way, since the lower end of the connection port between the first space and the second space is formed at a position higher than the inner peripheral lower end of the outer ring of the bearing in the vertical direction, even during vehicle travel Lubricating oil is stored in the lower part of the first space up to the same height as the lower end of the connection port. And since the lower end of this connection port is in a position higher in the vertical direction than the inner peripheral lower end of the outer ring of the bearing, at least a part of the rolling elements constituting the bearing is immersed in the stored lubricating oil. Insufficient lubrication is suppressed.

  Preferably, the gist of the second invention is the lubrication mechanism of the vehicle drive device according to the first invention, wherein the lower end of the connection port between the first space and the second space is in the vertical direction. The position is lower than the lower end of the first gear. In this way, the first gear is not immersed in the lubricating oil stored in the lower portion of the first space, so that the stirring resistance of the first gear can be suppressed.

  Preferably, the gist of the third invention is that in the lubricating mechanism of the vehicle drive device of the first invention or the second invention, the height of the oil surface of the lubricating oil stored in the first space, and The height of the oil level of the lubricating oil stored in the second space is equal to or higher than the lower end of the connection port when the vehicle is stopped, and the height of the oil level of the second space when the vehicle is running. Is lower than the lower end of the connection port, and the height of the oil surface of the first space coincides with the height of the lower end of the connection port in the vertical direction. In this way, even if the amount of lubricating oil stored in the lower portion of the first space increases during running, the oil flows out to the second space side, so the oil level of the lubricating oil stored in the lower portion of the first space is reduced. The height does not exceed the lower end of the connection port, the first gear is prevented from being immersed in the lubricating oil in the first space, and at least a part of the rolling elements constituting the bearing is in the first space. Soaked in lubricating oil. Therefore, insufficient lubrication of the bearing is suppressed, and the stirring resistance of the first gear is also suppressed.

  Preferably, the gist of the fourth invention is the lubricating mechanism of the vehicle drive device according to any one of the first invention to the third invention, wherein (a) the vehicle drive device is a drive source. A first reduction gear pair provided between the output shaft of the motor and a counter shaft parallel thereto, and a second reduction gear pair provided between the counter shaft and a differential case parallel thereto. The differential case and the differential device provided in the differential case, and the lubricating oil scooped up from the bottom of the case by at least one of the first reduction gear pair and the second reduction gear pair (B) a counter drive gear that is one of the first reduction gear pairs. The second gear is a counter driven gear that meshes with the counter drive gear that is the other of the first reduction gear pair, and (c) the first rotating shaft is an output shaft of the electric motor, and the second rotating shaft Is the counter shaft. In this way, insufficient lubrication of the bearing that supports the output shaft on which the counter drive gear that rotates at a high rotation and has a high necessity for lubrication is formed is effectively suppressed. In addition, the stirring resistance due to the counter drive gear being immersed in the lubricating oil stored in the first space is suppressed, and a practical drive device is obtained.

It is a figure which shows schematic structure of the drive device for vehicles to which this invention was applied. FIG. 2 is a skeleton diagram illustrating a configuration of a rear transaxle in FIG. 1. FIG. 3 is a perspective view schematically showing a part of a cross section cut along a cutting line A in FIG. 2. It is the figure which looked at FIG. 3 from the arrow B direction.

  Here, preferably, in this specification, the lower end corresponds to the lower end in the vertical direction.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, and the like of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a diagram showing a schematic configuration of a vehicle drive device 10 to which the present invention is applied. In FIG. 1, this vehicle drive device includes an engine 12 constituted by a known internal combustion engine such as a gasoline engine or a diesel engine that burns fuel and outputs motive power, and an electric motor 14. 14 includes a front transaxle 20 that selectively outputs one or both of the powers 14 to rotationally drive the pair of left and right front axles 16 and the front wheels 18, and an electric motor 22. An electric four-wheel drive device including a rear axle (axle) 24 and a rear transaxle 28 that rotationally drives a rear wheel 26.

  Such an electric four-wheel drive vehicle, for example, travels by the power of the motor 14 and the motor 22 when the vehicle starts, and travels by the power of the engine 12 in a travel region where the operating efficiency of the engine 12 is good. It has become. Further, when the engine 12 has poor operating efficiency, such as when traveling at a low speed or down a gentle slope, the operation of the engine 12 is stopped and the vehicle is driven by the power of the motor 14. Further, during acceleration traveling, the vehicle travels with the power of the engine 12, and the power of the electric motor 14 and the electric motor 22 is supplementarily used. Further, at the time of deceleration (including when the accelerator is off), the motor 14 and the motor 22 are operated as a generator to convert kinetic energy into electric energy and collect it. In addition, when the front tire slips when traveling on a low friction road, the motor 14 is operated as a generator to absorb engine power and reduce the driving force of the front wheels 18. The stability of the vehicle is ensured by operating the electric motor 22 using the generated electric power to bring it into a four-wheel drive state.

  The rear transaxle 28 corresponds to a vehicle drive device that is a main part of the present invention. Hereinafter, the rear transaxle 28 will be described in detail.

  FIG. 2 is a skeleton diagram for explaining the configuration of the rear transaxle 28 of FIG. 1, and is a view of the vehicle as viewed from above. In FIG. 2, the rear transaxle 28 includes a motor 22 as a drive source, a first reduction gear pair 34 provided between an output shaft 30 of the motor 22 and a counter shaft 32 parallel thereto, and a counter shaft 32. And a second reduction gear pair 38 provided between the output shaft 30 of the electric motor 22 and the coaxial differential case 36 parallel to the counter shaft, and the differential case 36 and the differential case 36 provided in the differential case 36. A two-shaft type vehicle having a differential device 42 composed of a mechanism 40 and rotationally driving a pair of rear axles 24 by torque transmitted from the electric motor 22 via the first reduction gear pair 34 and the second reduction gear pair 38. Drive device. In the present embodiment, the components of the rear transaxle 28 are arranged in the order of the electric motor 22, the first reduction gear pair 34, and the second reduction gear pair 38 (differential device 42) from the left side of the vehicle in the transaxle case 44. ing. Hereinafter, when referring to the left side of the vehicle, it refers to the motor 22 side relative to the second reduction gear pair 38, and when referring to the right side of the vehicle, refers to the side of the second reduction gear pair 38 relative to the motor 22. And In this embodiment, the output shaft 30 corresponds to the first rotating shaft of the present invention, the counter shaft 32 corresponds to the second rotating shaft of the present invention, and the transaxle case 44 corresponds to the case of the present invention.

  The output shaft 30 of the electric motor 22 is a stepped hollow cylindrical member whose one end (the vehicle right side) has a larger diameter than the center and the other end (the vehicle left side). The rotor 22a of the electric motor 22 is connected to the central portion of the output shaft 30 in the longitudinal direction, and bearings (output shaft bearings) 46 and 47 are fitted to the diameter-expanded portion of one end and the other end. It has been. The output shaft 30 is rotatably supported by the transaxle case 44 via the bearings 46 and 47.

  The first reduction gear pair 34 includes a counter drive gear 48 on the small diameter side and a counter driven gear 50 on the large diameter side that meshes therewith. The counter drive gear 48 is integrally fixed to the distal end side of one end portion of the output shaft 30. Further, the counter driven gear 50 is integrally fixed to one end portion (the vehicle left side) of the counter shaft 32 in a state where it is engaged with the counter drive gear 48. The counter drive gear 48 corresponds to the first gear of the present invention, and the counter driven gear 50 corresponds to the second gear of the present invention.

  The counter shaft 32 is provided in front of the vehicle with respect to the output shaft 30, the differential case 36, the counter drive gear 48, and a final driven gear 56 described later. Accordingly, the counter driven gear 50 is disposed on the foremost side in the transaxle case 44. A pair of bearings (counter shaft bearings) 52 are fitted to one end and the other end of the counter shaft 32. The counter shaft 32 is rotatably supported by the transaxle case 44 through the pair of bearings 52.

  The second reduction gear pair 38 includes a small-diameter final drive gear 54 and a large-diameter final driven gear 56 that meshes therewith. The final drive gear 54 is integrally fixed to the other end portion of the counter shaft 32. Further, the final driven gear 56 is fitted and fixed integrally to the outer peripheral portion of the differential case 36 in a state of meshing with the final drive gear 54.

  The differential case 36 includes a main body portion 36a that accommodates the differential mechanism 40, and a pair of cylindrical end portions 36b that protrude in the axial direction from both sides in the axial direction of the main body portion 36a in the axial direction. I have. A pair of bearings (differential case bearings) 60 are fitted on the outer peripheral surfaces of the pair of cylindrical end portions 36b. The differential case 36 is rotatably supported by the transaxle case 44 through the pair of bearings 60.

  The differential mechanism 40 is a well-known so-called bevel gear type. That is, a pair of side gears 62 opposed to each other on the rotational axis in the main body portion 36a of the differential case 36 and the differential case 36 in a state orthogonal to the rotational axis of the differential case 36 between the pair of side gears 16. A pair of pinion gears 66 that are rotatably supported by a fixed pinion shaft 64 and mesh with the pair of side gears 62 are provided. The pair of rear axles 24 are integrally connected to a pair of side gears 62. The differential device 42 including the differential case 36 and the differential mechanism 40 has a pair of rear axles by torque transmitted from the motor 22 via the first reduction gear pair 34 and the second reduction gear pair 38. The pair of rear axles 24 are rotationally driven while allowing a difference in rotational speed of 24. One of the pair of rear axles 24 on the left side of the vehicle is connected to one of the pair of rear wheels 26 on the left side of the vehicle through an output shaft 30 formed in a hollow cylindrical shape.

  The transaxle case 44 includes a plurality of divided case portions divided into three in the axial direction of the rear axle 24, specifically, a cylindrical first divided case portion 68 that mainly accommodates the first reduction gear pair 34, The lid-shaped second divided case portion 70 that mainly accommodates the electric motor 22 and the lid-shaped third divided case portion 72 that mainly accommodates the second reduction gear pair 38 and the differential device 42 are fastened together by bolts (not shown). By being done, it is comprised oiltight. In the transaxle case 44 of the present embodiment, the first split case portion 68 is positioned near the center in the vehicle width direction, the second split case portion 70 is connected to the vehicle left side of the first split case portion 68, and the third The split case portion 72 is a three-split type connected to the vehicle right side of the first split case portion 68, that is, the opposite side of the first split case portion 68 from the second split case portion 70. Each of these divided case portions is formed of a cast light alloy such as aluminum die casting.

  The first split case 68 is a first support integrally provided so as to close an outer peripheral wall 68a formed in a cylindrical shape on the outer peripheral side of the first reduction gear pair 34 and an opening on the left side of the vehicle on the outer peripheral wall 68a. And a wall 68b. The first support wall 68b includes a first support portion 74 that supports a space between the motor 22 and the counter drive gear 48 at one end portion of the output shaft 30 via a bearing 47, and one end portion, that is, a pair of differential cases 36. A second support portion 76 that supports one of the left ends of the cylindrical end portion 36 b of the vehicle via a bearing 60 and a third support portion 78 that supports one end portion of the counter shaft 32 via a bearing 52 are provided. Yes. Here, the second support portion 76 is connected via a partially cylindrical case cylindrical portion 82 projecting from the opening edge of the first support portion 74 toward the differential case 36 side.

  The second split case 70 includes an outer peripheral wall 70a formed in a cylindrical shape on the outer peripheral side of the electric motor 22, and a second support wall 70b provided integrally so as to close the opening on the left side of the vehicle on the outer peripheral wall 70a. I have. The second support wall 70 b supports the other end of the electric motor 22 on the left side of the vehicle via a bearing 46 so as to be rotatable.

  The third split case 72 is integrally provided so as to block the outer peripheral wall 72a formed in a cylindrical shape on the outer peripheral side of the differential device 42 and the second reduction gear pair 38 and the opening on the right side of the vehicle on the outer peripheral wall 72a. And a third support wall 72b. The third support wall 72 b rotatably supports the other end of the differential case 36, that is, the other of the pair of cylindrical ends 36 b on the right side of the vehicle via a bearing 60.

  FIG. 3 is a perspective view schematically showing a part of a cross section cut along a cutting line A shown in FIG. In FIG. 3, the counter driven gear 50 that meshes with the counter shaft 32 and the counter drive gear 48 supported by the bearing 52 is omitted. As shown in FIG. 3, the rear wheel axle 24 passes through the inner periphery of the hollow cylindrical output shaft 30, and a counter drive gear 48 is integrally formed on the outer periphery side of the output shaft 30. . The output shaft 30 is rotatably supported by a bearing 47 that is fitted to the first support portion 74 of the first support wall 60 b of the first split case portion 68.

  A bearing 47 that rotatably supports one end side of the output shaft 30 on which the rear wheel axle 24, the output shaft 30, the counter drive gear 48, and the counter drive gear 48 are formed is mainly provided in the first split case portion 68. A first space 84 surrounded by a case cylindrical portion 82 for housing the housing, and an outer periphery for housing mainly the counter shaft 32 (not shown in FIG. 3), the counter driven gear 50 (not shown in FIG. 3), and the bearing 52. A second space 86 surrounded by the wall 68a is formed. The first space 84 is a cylindrical space formed by being surrounded by a partially cylindrical case cylindrical portion 82 that is a part of the transaxle case 44. The second space 86 is a space formed by being surrounded by an outer peripheral wall 68 a that is mainly a part of the transaxle case 44. The first space 84 and the second space 86 are continuously connected to each other, and the lower end 84a in the vertical direction of the first space is formed at a position higher than the lower end 86a in the vertical direction of the second space. Yes. Further, a connection port 88 indicated by a one-dot chain line connecting the first space 84 and the second space 86 is formed. The connection port 88 has an upper end 88 a and a lower end 88 b in the vertical direction defined by the transaxle case 44, and the lower end 88 b in the vertical direction of the connection port 88 is the lower end 84 a in the vertical direction of the first space 84 and the second space 86. , 86a is formed at a higher position in the vertical direction.

  4 is a view of FIG. 3 as viewed from the direction of arrow B, that is, FIG. 3 is a view of FIG. In FIG. 4, the upper side corresponds to the vertical upper side of the vehicle. As shown in FIG. 4, a counter drive gear 48 is engaged with a counter driven gear 50, and an output shaft 30 on which the counter drive gear 48 is formed is rotatably supported by a bearing 47. The bearing 47 can rotate and revolve between an inner ring 47a fitted to the outer periphery of the output shaft 30, an outer ring 47b fitted to the inner circumference of the case cylindrical portion 82, and the inner ring 47a and the outer ring 47b. It is composed of a plurality of balls 47c that are inserted to allow relative rotation of the inner ring 47a and the outer ring 47b.

  As described above, the position of the lower end 88 b of the connection port 88 is formed at a position higher than the lower end 84 a of the first space 84 in the vertical direction. More specifically, the lower end 88 b of the connection port 88 is formed at a position higher in the vertical direction than the inner peripheral lower end 49 of the outer ring 47 b constituting the bearing 47. Alternatively, the lower end 88 b of the connection port 88 is formed at a position higher in the vertical direction than at least a part of the ball 47 when the ball 47 c revolving with the rotation of the output shaft 30 is at the lowest position in the vertical direction. Has been. The lower end 88b of the connection port 88 is formed at a position lower than the lower end 48a of the counter drive gear 48 in the vertical direction. As a result, a lubricating oil storage space 90 is formed in the lower portion (bottom portion) of the first space 84 and is indicated by hatching with the height of the lower end 88b of the connection port 88 as the upper limit.

  In the present embodiment, when the vehicle is stopped, the transaxle case is such that the oil level of the lubricating oil stored in the lower part (bottom part) of the transaxle case 44 is higher than the lower end 88b of the connection port 88. The amount of lubricating oil in 44 is adjusted. At this time, the lubricating oil stored in the first space 84 and the lubricating oil stored in the second space 86 merge, and the oil level of the first space 84 and the oil level of the second space 86 are the same. The height of the connection port 88 is equal to or higher than the lower end 88b. In the present embodiment, when the vehicle is stopped, the height of the oil level is the height H1 indicated by the broken line in FIG. 4, and at least a part of the counter drive gear 48, the counter driven gear 50, and the final driven gear 56 is the bottom of the transaxle case 44. Soaked in lubricating oil stored in

  Further, the counter driven gear 50 and the final driven gear 56 are configured to scrape up and supply the lubricating oil stored in the bottom of the transaxle case 44 to the respective lubricated parts by rotating. That is, the rear transaxle 28 of the present embodiment employs a scraping lubrication system that scoops up the lubricating oil stored in the bottom of the transaxle case 44 and supplies it to each lubrication site. The lubrication site corresponds to, for example, the meshing portion of the first reduction gear pair 34 and the second reduction gear pair 38, the gear meshing portion and the rotational sliding portion of the differential mechanism 40, and each bearing. The first support wall 68b of the first split case portion 68 is provided with the motor 22 and the first reduction gear 34 and so that the lubricating oil scraped up by the counter driven gear 50 and the final driven gear 56 does not scatter toward the motor 22. It also functions as a partition wall for partitioning the second reduction gear pair 38.

  Returning to FIG. 2, in the transaxle case 44, the lubricating oil stored at the bottom of the transaxle case 44 is reduced in the transaxle case 44 for the purpose of reducing the stirring resistance of the lubricating oil by the counter driven gear 50 that increases as the vehicle speed V increases. In order to lower the oil level position, a reservoir tank 92 is provided for storing a part of the lubricating oil to be scraped up. The reservoir tank 92 is provided in the outer peripheral walls 68a, 70a, and 72a of the divided case portions 68, 70, and 72 so that the lubricating oil can be stored at a position higher than the oil level at the bottom of the transaxle case 44. A plate-shaped tank wall 68c, 70c, and 72c extending upward from the peripheral surface is provided. In this embodiment, the reservoir tank 92 is disposed on the rearmost side of the transaxle case 44 (the vehicle rear side of the first reduction gear pair 34 and the second reduction gear pair 38 including the crankshaft 32). Since most of the lubricating oil scraped up by the counter driven gear 50 is blown upward and rearward, the reservoir tank 92 is located at a position where the lubricating oil to be blown can be efficiently stored, that is, at the end of the transaxle case 44. It is arranged on the side. As a result, the rotational speed of the counter-driven gear 50, which is faster than the final driven gear 56 and excellent in the performance of scavenging the lubricating oil (a large amount of scavenging), is smoothly performed. . The lubricating oil stored in the reservoir tank 92 is supplied to other lubricating parts from a lubricating oil supply port (not shown) provided in the reservoir tank 92, or overflows from the reservoir tank 92 when it accumulates a predetermined amount or more. As a result, the bottom of the transaxle case 44 is returned. The lubrication mechanism of the present invention includes a first reduction gear pair 34, a second reduction gear pair 38, a transaxle case 44, a reservoir tank 92, and the like.

  A lubrication mechanism for the rear transaxle 28, which is a part of the vehicle drive device 10 configured as described above, will be described. When the vehicle is stopped, the amount of lubricating oil is set so that the oil level of the lubricating oil stored at the bottom of the transaxle case 44 is the height H1 indicated by the broken line. At this time, the counter driven gear 50 and a part of the final driven gear 56 are immersed in the lubricating oil stored at the bottom of the transaxle case 44. On the other hand, when the vehicle is running, the lubricating oil stored at the bottom of the transaxle case 44 is scooped up by the counter driven gear 50 and the final driven gear 56 and supplied to each lubricating part and the reservoir tank 92 to increase the oil level. In the first space 84, the oil level of the lubricating oil stored in the storage space 90 becomes equal to the height H2 of the lower end 88b of the connection port 88 indicated by a one-dot chain line. Further, in the second space 86, the oil level of the lubricating oil is lower than the height H2 of the lower end 88b of the connection port 88, and the lubricating oil stored in the first space 84 is the oil level height H2. When the amount of storage exceeds (the height H2 of the lower end 88b of the connection port 88), it flows down to the second space 86 side. It should be noted that oil or the like scraped up by the counter drive gear 48 or the like is supplied to the traveling storage space 90.

  As described above, the lubricating oil is stored in the storage space 90 of the first space 84 even while the vehicle is traveling. Here, the oil level of the lubricating oil stored in the first space 84 during traveling of the vehicle becomes the height H2 of the lower end 88b of the connection port 88, and a part of the ball 47c of the bearing 47 is lubricated during traveling. Therefore, insufficient lubrication of the bearing 47 is suppressed. In addition, since the output shaft 30 is rotated at a relatively high rotation, there is a high necessity for lubrication of the bearing 47 that supports the output shaft 30. However, the bearing 47 is effectively lubricated by the above configuration. Further, since the height H2 of the lower end 88b of the connection port 88 is lower than the lower end 48a of the counter drive gear 48 in the vertical direction, the counter drive gear 48 is not immersed in the stored lubricating oil. Therefore, the stirring resistance generated when the counter drive gear 48 is immersed does not occur. As described above, both the suppression of insufficient lubrication and the suppression of the agitation resistance of the counter drive gear 48 due to the supply of an appropriate amount of lubricating oil to the bearing 47 during traveling are achieved.

  As described above, according to the present embodiment, the lower end 88b of the connection port 88 between the first space 84 and the second space 86 is formed at a higher position in the vertical direction than the inner peripheral lower end 49 of the outer ring 47b of the bearing 47. Therefore, the lubricating oil is stored in the lower part of the first space 84 up to the same height as the lower end 88b of the connection port 88 even when the vehicle is running. Since the lower end 88b of the connection port 88 is higher in the vertical direction than the inner peripheral lower end 49 of the outer ring 47b of the bearing 47, at least a part of the ball 47c constituting the bearing 47 is caused by the stored lubricating oil. It is immersed and insufficient lubrication of the bearing 47 is suppressed.

  Further, according to the present embodiment, the lower end 88b of the connection port 88 between the first space 84 and the second space 86 is located at a position lower than the lower end 48a of the counter drive gear 48 in the vertical direction. Is not immersed in the lubricating oil stored in the lower portion of the first space 84, the stirring resistance of the counter drive gear 48 can be suppressed.

  Further, according to the present embodiment, the height of the oil level of the lubricating oil stored in the first space 84 and the height of the oil level of the lubricating oil stored in the second space 86 are determined when the vehicle stops. When the vehicle travels, the oil level of the second space 86 is lower than the lower end 88b of the connection port 88 and the oil level of the first space 84 is high. And the vertical height of the lower end 88b of the connection port 88 coincide with each other. In this way, even if the amount of lubricating oil stored in the lower part of the first space 84 increases during traveling, it flows out to the second space 86 side, so that the lubricating oil stored in the lower part of the first space 84 is reduced. The height of the oil level does not exceed the lower end 88b of the connection port 88, the counter drive gear 48 is suppressed from being immersed in the lubricating oil in the first space 84, and at least the balls 47c constituting the bearing 47 A part is immersed in the lubricating oil in the first space 47. Therefore, insufficient lubrication of the bearing 47 is suppressed, and the stirring resistance of the counter drive gear 48 is also suppressed.

  Further, according to the present embodiment, the vehicle drive device 10 includes the first reduction gear pair 34 provided between the electric motor 22 as a driving source, the output shaft 30 of the electric motor 22 and the counter shaft 32 parallel thereto. And a differential gear unit 38 provided between the counter shaft 32 and the differential case 36 parallel to the counter shaft 32, the differential case 36 and the differential mechanism 40 provided in the differential case 36. 42 and a reservoir tank 92 in which a part of the lubricating oil scraped up from the bottom of the transaxle case 44 by at least one of the first reduction gear pair 34 and the second reduction gear pair 38 is stored in the transaxle case 44. The first reduction gear pair 34 includes a counter drive gear 48 and a counter driven gear 50. Constructed. In this way, insufficient lubrication of the bearing 47 that supports the output shaft 30 in which the counter drive gear 48 that rotates at a high speed and has a high necessity for lubrication is formed is effectively suppressed. In addition, the stir resistance due to the counter drive gear 48 being immersed in the lubricating oil stored in the first space 86 is suppressed, and the vehicle drive device 10 is practical.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

  For example, in the above-described embodiment, the rear transaxle 28 of the vehicle drive device 10 is configured to rotationally drive the pair of left and right rear axles 24 and the rear wheels 26 by the power of the electric motor 22. The present invention is not limited to the drive device, and may be applied to, for example, a hybrid drive device including an engine.

  In the above-described embodiment, in the counter drive gear 48 and the counter driven gear 50, insufficient lubrication of the counter drive gear 48 is suppressed and stirring resistance of the counter drive gear 48 is suppressed. The gear 48 and the counter driven gear 50 are not limited. For example, the present invention can be applied to the final drive gear 54 and the final driven gear 56 constituting the second reduction gear pair 38. In such a case, insufficient lubrication of the bearing 52 that supports the final drive gear 54 is suppressed, and stirring resistance of the final drive gear 54 is suppressed.

  In the above-described embodiment, the cylindrical first space 84 is formed by the case cylindrical portion 82 formed in a cylindrical shape, but the structure of the first space 84 is not necessarily limited to the cylindrical shape. The first space 84 can be appropriately changed within a range in which a portion lower in the vertical direction than the lower end 88b of the connection port 88 is formed and a storage space 90 in which lubricating oil can be stored is formed.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

10: Vehicle drive device 22: Electric motor 30: Output shaft (first rotation shaft)
32: Counter shaft (second rotary shaft)
34: first reduction gear pair 36: differential case 38: second reduction gear pair 40: differential mechanism 42: differential device 44: transaxle case (case)
47: Bearing 47b: Outer ring 48: Counter drive gear (first gear)
50: Counter driven gear (second gear)
84: First space 86: Second space 88: Connection port 88b: Lower end of connection port 92: Reservoir tank

Claims (4)

A first space surrounded by a case for housing a first gear and a bearing that rotatably supports one end of the first rotating shaft on which the first gear is formed; and a second gear meshing with the first gear. A lubricating mechanism for a vehicle drive device, comprising: a second space surrounded by the case accommodating the formed second rotating shaft;
A lubricating mechanism for a vehicle drive device, wherein a lower end of a connection port between the first space and the second space is positioned higher than a lower end of an inner periphery of an outer ring of the bearing in a vertical direction.   The lubricating mechanism for a vehicle drive device according to claim 1, wherein a lower end of a connection port between the first space and the second space is at a position lower than a lower end of the first gear in a vertical direction. The height of the lubricating oil stored in the first space and the height of the lubricating oil stored in the second space are equal to or higher than the lower end of the connection port when the vehicle is stopped. I will
When the vehicle is traveling, the height of the oil level in the second space is lower than the lower end of the connection port, and the height of the oil level in the first space and the height in the vertical direction of the lower end of the connection port. And the lubricating mechanism of the vehicle drive device according to claim 1 or 2. The vehicle drive device includes an electric motor as a drive source, a first reduction gear pair provided between an output shaft of the electric motor and a counter shaft parallel thereto, and a counter case and a differential case parallel thereto. At least one of a second reduction gear pair provided therebetween, a differential device including a differential case and a differential mechanism provided in the differential case, and the first reduction gear pair and the second reduction gear pair A reservoir tank in which a part of the lubricating oil scraped up from the bottom of the case is stored is provided in the case.
The first gear is a counter drive gear that is one of the first reduction gear pairs, and the second gear is a counter driven gear that meshes with the counter drive gear that is the other of the first reduction gear pairs;
4. The lubricating mechanism for a vehicle drive device according to claim 1, wherein the first rotating shaft is an output shaft of the electric motor, and the second rotating shaft is the counter shaft. 5.

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