WO2019208642A1

WO2019208642A1 - Vehicle power transmission device

Info

Publication number: WO2019208642A1
Application number: PCT/JP2019/017458
Authority: WO
Inventors: 山田　賢; 土橋　誠; 誠人西田; 敬士葛原; 康夫木間; 勇司古賀; 慶明小西
Original assignee: 本田技研工業株式会社
Priority date: 2018-04-26
Filing date: 2019-04-24
Publication date: 2019-10-31
Also published as: JPWO2019208642A1; CN112020618A; JP6923753B2; DE112019002135T5; CN112020618B

Abstract

A vehicle power transmission device in which a side wall (17a) forwardly of a meshing portion (38) between a final driven gear (29) and a final drive gear (28) is provided with an oil-collecting recess (50) which collects oil that has been scooped up by the final driven gear (29) from a bottom portion of a gear case (16, 17) and supplies the oil to a bearing (32). Accordingly, even when the oil scooped up by the final driven gear (29) is blocked by the meshing portion (38) and becomes less likely to reach the bearing (32), the oil that has passed through the meshing portion (38) can be collected by the oil-collecting recess (50) efficiently and supplied to the bearing (32), whereby the bearing (32) supporting the differential gear (13) can be lubricated effectively.

Description

Power transmission device for vehicle

The present invention relates to a vehicle power transmission device that lubricates a bearing that supports a differential gear on a gear case with oil scraped up by a final driven gear provided in a differential gear housed in a front portion of the gear case.

The rotation of the motor shaft of the electric motor is differential through a counter drive gear provided on the motor shaft, a counter driven gear provided on the counter shaft, a final drive gear provided on the counter shaft, and a final driven gear provided on the differential shaft. An axle drive device for transmitting to a gear is known from Japanese Patent Application Laid-Open No. 2004-228561.

Japanese Unexamined Patent Publication No. 2005-201316

By the way, in the above conventional axle drive device, since the differential gear is arranged at the front part of the gear case, the oil staying at the bottom part of the gear case is scraped upward and rearward by the final driven gear provided in the differential gear. Even if you try to lubricate, the rear part of the final driven gear meshes with the front part of the final drive gear. The problem of difficulty is addressed by using a counter driven gear provided on the counter shaft to rake up the oil rearward and supply it to the lubricated part.

However, such a method has a problem that the vertical dimension of the gear case is increased because the diameter of the counter driven gear needs to be increased.

The present invention has been made in view of the above-described circumstances, and it is an object of the present invention to effectively lubricate a bearing that supports a differential gear with oil that is scraped up by a final driven gear provided in a differential gear that is housed in a front portion of a gear case. And

To achieve the above object, according to a first aspect of the present invention, a gear case, a differential gear housed in a front portion of the gear case, a bearing for supporting the differential gear on a side wall of the gear case, A final driven gear provided on the outer periphery of the differential gear; and a final drive gear that transmits a driving force of a driving source to the final driven gear via an input shaft, the final driven gear being forward of the input shaft in the vehicle traveling direction. A power transmission device for a vehicle disposed on a side, wherein oil collected from the bottom of the gear case by the final driven gear is collected on the side wall in front of the meshing portion of the final driven gear and the final drive gear. Supply to the bearing The vehicle power transmission device, characterized in that the oil collecting recess is provided is proposed.

According to a second feature of the present invention, in addition to the first feature, an oil guide wall arranged along the rear lower part of the final driven gear is provided, and the meshing portion is horizontally arranged to collect the oil. A vehicular power transmission device is proposed which is located between a recess and the oil guide wall.

According to a third feature of the present invention, in addition to the second feature, an oil pump is provided at a lower portion of the gear case, and the oil guide wall includes a first space for housing the final driven gear, and the oil. A vehicular power transmission device is proposed, which is disposed between the second space in which the pump is accommodated.

According to a fourth feature of the present invention, in addition to the third feature, the oil level of the oil staying at the bottom of the gear case is located below the upper end of the oil guide wall, and the oil guide wall A vehicle power transmission device is proposed in which an opening for communicating the first space and the second space is formed in a lower portion of the vehicle.

According to a fifth feature of the present invention, in addition to the fourth feature, a vehicle power transmission device is proposed in which the opening is positioned above the lower end of the final driven gear. .

According to a sixth feature of the present invention, in addition to any one of the first to fifth features, a motor case that houses therein the electric motor that is the drive source is coupled to the gear case, A vehicular power transmission device is proposed in which an internal space of the motor case and a communication hole for communicating the internal space of the gear case are formed below the oil level of oil staying at the bottom of the gear case.

According to a seventh feature of the present invention, in addition to any one of the first to sixth features, the oil collecting recess disposed forward of the center of the final driven gear faces the bearing. A bottom wall extending radially inward, a front inclined wall connected to the front side of the bottom wall and inclined at a first inclination angle, and a rear inclination inclined to a rear side of the bottom wall and inclined at a second inclination angle There is proposed a vehicle power transmission device having a wall and a groove-like cross section, wherein the second inclination angle is smaller than the first inclination angle.

Further, according to an eighth feature of the present invention, in addition to the seventh feature, there is proposed a vehicle power transmission device characterized in that the width of the bottom wall decreases toward the bearing.

According to a ninth feature of the present invention, in addition to the seventh or eighth feature, an inclination start line of the rear inclined wall constituting the rear edge of the groove-shaped cross section is formed with respect to the rear in the horizontal direction. The angle is set to be 90 ° or more when the vehicle climbs at the maximum climb angle, and the angle formed by the inclination start line of the front inclined wall constituting the front edge of the groove-shaped cross section with respect to the rear in the horizontal direction is A vehicle power transmission device is proposed which is set to be 170 ° or less when the vehicle descends at a maximum descending angle.

The electric motor 11 of the embodiment corresponds to the drive source of the present invention, the left housing 15 of the embodiment corresponds to the motor case of the present invention, and the central housing 16 and the right housing 17 of the embodiment correspond to the present invention. The angular roller bearing 32 of the embodiment corresponds to the bearing of the present invention.

According to the first aspect of the present invention, a vehicle power transmission device includes a gear case, a differential gear housed in a front portion of the gear case, a bearing that supports the differential gear on a side wall of the gear case, and an outer periphery of the differential gear. A final driven gear is provided, and a final drive gear that transmits the driving force of the drive source to the final driven gear via the input shaft, and the final driven gear is disposed on the front side in the vehicle traveling direction with respect to the input shaft.

An oil collecting recess that collects oil collected from the bottom of the gear case by the final driven gear and supplies it to the bearing is provided on the side wall in front of the meshing portion of the final driven gear and the final drive gear. Even if the oil is blocked by the meshing part of the final driven gear and the final drive gear and becomes difficult to reach the bearing, the oil that has passed through the meshing part of the final driven gear and the final drive gear is efficiently collected by the oil collecting recess and supplied to the bearing. By doing so, the bearing can be effectively lubricated.

According to the second aspect of the present invention, the oil guide wall is disposed along the rear lower portion of the final driven gear, and the meshing portion is positioned between the oil collecting recess and the oil guide wall in the horizontal direction. Even if the oil driven up by the final driven gear is obstructed by the meshing part and it is difficult to reach the bearing, the oil driven up by the final driven gear is supplied forward along the oil guide wall and efficiently supplied to the oil collecting recess. The bearing can be lubricated.

According to the third aspect of the present invention, the oil pump is disposed below the gear case, and the oil guide wall is disposed between the first space that houses the final driven gear and the second space that houses the oil pump. Therefore, the oil guide wall functions as a baffle plate to suppress the oil surface undulation caused by the rotation of the differential gear, thereby preventing the oil pump from sucking air.

According to the fourth aspect of the present invention, the oil level of the oil staying at the bottom of the gear case is located below the upper end of the oil guide wall, and the first and second storage portions are disposed below the oil guide wall. Is formed so that the first storage portion and the second storage portion partitioned by the oil guide wall are communicated with each other by the opening portion, and the oil level of the first storage portion and the second storage portion is increased. In addition, it is possible to equalize, and it is difficult to entrain air when the oil passes through the opening, thereby preventing generation of bubbles.

According to the fifth feature of the present invention, since the opening is located above the lower end of the final driven gear, the opening can be formed without causing the bottom of the gear case to bulge downward, and the large size of the gear case. Is prevented.

According to a sixth aspect of the present invention, a motor case that houses an electric motor as a driving source is coupled to the gear case, and a communication hole that communicates the internal space of the motor case and the internal space of the gear case is provided in the gear case. Since it is formed below the oil level of the oil staying at the bottom, even if the oil in the gear case internal space flows out of the communication hole into the motor case internal space, The bearing can be reliably lubricated.

According to the seventh aspect of the present invention, the oil collecting concave portion arranged in front of the center of the final driven gear has a bottom wall extending radially inward toward the bearing and a front side of the bottom wall. A front inclined wall inclined at one inclination angle and a rear inclined wall connected to the rear side of the bottom wall and inclined at a second inclination angle are formed in a groove-like cross section, and the second inclination angle is the first inclination angle. Since the angle is smaller than the angle, the oil is efficiently guided to the bottom wall of the oil collecting recess by the rear inclined wall having a weak inclination angle, and the oil is effectively blocked by the front inclined wall having a strong inclination angle to be used as a bearing. Can be supplied automatically.

Further, according to the eighth feature of the present invention, since the width of the bottom wall decreases toward the bearing, the oil collected in the oil collecting recess can be efficiently supplied to the bearing.

According to the ninth feature of the present invention, the angle formed by the inclination start line of the rear inclined wall constituting the trailing edge of the groove-shaped cross section with respect to the rear in the horizontal direction is when the vehicle climbs at the maximum climb angle. The angle formed by the inclination start line of the front inclined wall constituting the front edge of the groove-shaped cross section with respect to the horizontal rear is set to be 90 ° or more, and is 170 ° when the vehicle descends at the maximum downhill angle. Since it is set to be as follows, oil can be reliably supplied to the bearings when the vehicle is traveling uphill or downhill.

FIG. 1 is a longitudinal sectional view (cross-sectional view taken along line 1-1 of FIG. 2) of a power unit of an automobile. (First embodiment) FIG. 2 is a view taken along line 2-2 of FIG. (First embodiment) FIG. 3 is a view taken along line 3-3 in FIG. (First embodiment) 4 is an enlarged sectional view taken along line 4-4 of FIG. (First embodiment) FIG. 5 is an explanatory diagram of the action when the automobile is climbing up and down. (First embodiment)

11 Electric motor (drive source)
13 Differential gear 15 Left housing (motor case)
16 Central housing (gear case)
16b Communication hole 16c Oil guide wall 17 Right housing (gear case)
17a Side wall 20 Input shaft 28 Final drive gear 29 Final driven gear 32 Angular roller bearing (bearing)
38 meshing portion 45 oil pump 47 first space 48 second space 49 opening 50 oil collecting recess 50a bottom wall 50b front side inclined wall 50c rear side inclined wall 50d front side inclined wall inclination start line 50e rear side inclined wall inclination start line θ1 First tilt angle θ2 Second tilt angle α Angle formed by the tilt start line of the rear tilt wall with respect to the rear in the horizontal direction β Angle formed by the tilt start line of the front tilt wall with respect to the rear in the horizontal direction

Hereinafter, embodiments of the present invention will be described with reference to FIGS.

First embodiment

As shown in FIGS. 1 and 2, the power unit of the electric vehicle includes a motor housing 14 that houses an electric motor 11, a speed reducer 12, and a differential gear 13. The motor housing 14 is divided into three in the vehicle width direction. The left housing 15, the central housing 16, and the right housing 17. A first accommodating portion 43 is defined between the left housing 15 and the central housing 16, and a second accommodating portion 44 is defined between the central housing 16 and the right housing 17.

The electric motor 11 disposed in the first housing portion 43 includes a motor shaft 20 supported by the left housing 15 and the central housing 16 via

ball bearings

18 and 19, respectively, a rotor 21 fixed to the motor shaft 20, And a stator 22 fixed to the central housing 16 so as to surround the outer periphery of the rotor 21. Oil is stored at the bottom of the motor housing 14, and the oil level is OL.

The speed reducer 12 disposed in the second housing portion 44 includes a first speed reduction gear 23 fixed to the tip of the motor shaft 20 protruding rightward from the right housing 17, and an angular roller on each of the central housing 16 and the right housing 17. A reduction shaft 26 supported via

bearings

24 and 25, a second reduction gear 27 fixed to the reduction shaft 26 and meshing with the first reduction gear 23, and a final drive gear 28 fixed to the reduction shaft 26 And a final driven gear 29 fixed to the outer periphery of the differential gear 13 and meshing with the final drive gear 28.

The differential case 30 that constitutes the outline of the differential gear 13 disposed in the second accommodating portion 44 is supported by the central housing 16 and the right housing 17 via

angular roller bearings

31 and 32, respectively, and from the differential case 30 to the left. An inboard joint 34 provided at the tip of the extended long left output shaft 33 projects outward from the left housing 15, and an inboard joint 36 provided at the tip of the short right output shaft 35 extending rightward from the differential case 30 extends from the right housing 17. Projects outward. The left inboard joint 34 is connected to the left rear wheel via a left half shaft (not shown), and the left inboard joint 36 is connected to the right rear wheel via a right half shaft (not shown). The left end of the left output shaft 33 whose right end is supported by the differential gear 13 is supported by the left housing 15 via a ball bearing 37.

As apparent from FIG. 2, the first housing portion 43 and the second housing portion 44 are positioned on the side wall 16 a of the central housing 16 that partitions the first housing portion 43 and the second housing portion 44 at a position lower than the oil level OL. A communication hole 16b is formed to communicate with each other. An oil pump 45 and an oil strainer 46 are disposed in the rear lower part of the second housing portion 44 so as to overlap each other, and a front first space 47 for housing the differential gear 13, an oil pump 45 and an oil strainer 46. An arcuate oil guide wall 16c is formed along the outer periphery of the final driven gear 29 so as to partition the second space 48 on the rear side for housing the final driven gear 29. An opening 49 that allows the first space 47 and the second space 48 to communicate with each other is formed below the lower end of the oil guide wall 16c.

FIG. 3 shows the left side surface of the right housing 17 coupled to the right side surface of the central housing 16. The side wall 17 a of the right housing 17 includes a circular concave portion 17 b that covers the right side surface of the differential gear 13, and a concave portion. A bearing support hole 17c formed in the center of 17b and into which an angular roller bearing 32 for supporting the right end of the differential gear 13 is fitted, and an oil collecting recess 50 in which a part of the recess 17b is recessed in a groove shape are formed. . The oil collecting recess 50 extends obliquely forward and upward from the center of the differential gear 13 toward the radially outer side.

As shown in detail in FIGS. 3 and 4, the oil collecting recess 50 includes a flat bottom wall 50 a and a front inclined wall 50 b extending obliquely forward from the front end of the bottom wall 50 a and continuing to the wall surface of the recess 17 b of the right housing 17. And a rear inclined wall 50c extending obliquely rearward from the rear end of the bottom wall 50a and continuing to the wall surface of the recess 17b of the right housing 17 and having a groove shape in cross section. The width of the bottom wall 50a is gradually reduced from the radially outer side to the inner side, and the radially inner end thereof is connected to the bearing support hole 17c.

The inclination angle of the front inclined wall 50b with respect to the plane orthogonal to the axis of the differential gear 13 (the split surface of the right housing 17) is the first inclination angle θ1, and the inclination angle of the rear inclination wall 50c is the second inclination angle θ2. At this time, the second inclination angle θ2 is set smaller than the first inclination angle θ1. That is, the front inclined wall 50 b stands with respect to the split surface of the right housing 17, and the rear inclined wall 50 c lies with respect to the split surface of the right housing 17.

Next, the operation of the embodiment of the present invention having the above configuration will be described.

The first housing portion 43 partitioned between the left housing 15 and the central housing 16 of the motor housing 14 and the second housing portion 44 partitioned between the central housing 16 and the right housing 17 of the motor housing 14 are the central housing 16. Since the communication holes 16b are connected to each other, the oil staying in the second storage portion 44 is supplied to the first storage portion 43 and used for lubrication and cooling of the electric motor 11.

When the oil oil level staying in the second storage portion 44 changes as the vehicle travels, the oil in the first space 47 and the second space 48 on the front side of the second storage portion 44 travels through the opening 49, The oil level OL of the first space 47 and the second space 48 on the rear side can be made uniform. At this time, since the opening 49 is at a position much lower than the oil level OL, it is difficult to entrain air when the oil passes through the opening 49, and generation of bubbles can be prevented. Moreover, since the opening 49 is located above the lower end of the final driven gear 29, the opening 49 can be formed without causing the bottom of the central housing 16 to bulge downward, and the motor housing 14 is prevented from being enlarged. The

The oil guide wall 16c disposed between the first space 47 that accommodates the oil pump 45 and the second space 48 that accommodates the final driven gear 29 functions as a baffle plate, and the oil surface generated by the rotation of the differential gear 13 The oil pump 45 can be prevented from sucking air.

Further, by arranging the oil guide wall 16c along the rear lower portion of the final driven gear 29, the oil scooped up by the final driven gear 29 is supplied forward along the oil guide wall 16c, and the oil on the side wall 17a of the right housing 17 is supplied. The collecting recess 50 can be supplied.

Since the second inclined angle θ2 of the rear inclined wall 50c of the oil collecting recess 50 is small, the oil is smoothly guided to the rear inclined wall 50c and reaches the bottom wall 50a, where the front inclined having a large first inclined angle θ1. By being blocked by the wall 50b, the angular roller bearing 32 that flows radially inward along the bottom wall 50a, passes through the bearing support hole 17c, and supports the right end of the differential gear 13 to the right housing 17 is lubricated. . At this time, since the width of the bottom wall 50a of the oil collecting recess 50 decreases toward the angular roller bearing 32, the oil collected in the oil collecting recess 50 can be efficiently directed to the angular roller bearing 32. .

The differential gear 13 is disposed at the front portion of the motor housing 14, and the final drive gear 28 and the final driven gear are provided in a path through which the oil driven by the final driven gear 29 along the oil guide wall 16c is supplied to the angular roller bearing 32. Since the 29 meshing portions 38 (see FIG. 2) are located, the supply of oil is hindered by the meshing portions 38, and the oil may not easily reach the oil collecting recess 50.

However, according to the present embodiment, since oil is actively collected by the oil collecting recess 50 and supplied to the angular roller bearing 32, the supply of oil is obstructed by the meshing portion 38 of the final drive gear 28 and the final driven gear 29. Even if this is done, the required amount of oil can be supplied to the angular roller bearing 32 in addition to that.

The first housing portion 43 and the second housing portion 44 of the motor housing 14 communicate with each other through a communication hole 16b lower than the oil level OL, and the oil in the second housing portion 44 is used to lubricate and cool the electric motor 11. Even if the amount of oil in the second storage portion 44 decreases after flowing into the first storage portion 43, the amount of oil necessary for the angular roller bearing 32 is compensated for by the oil collection effect of the oil collection recess 50. Oil can be supplied.

FIG. 5 (A) shows a state where the vehicle climbs at the maximum possible climb angle δ. In this case, since the motor housing 14 is tilted upward, the tilt start line 50e, which is the rear edge of the rear inclined wall 50c of the oil collecting recess 50, is also tilted rearward, but the tilt start line 50e is rearward in the horizontal direction. The formed angle α is set to 90 ° or more. Thus, even when the vehicle climbs at the assumed maximum climb angle δ, it is possible to reliably introduce oil urged downward by gravity into the oil collecting recess 50.

FIG. 5B shows a state where the vehicle descends at the assumed maximum descending angle δ. In this case, since the motor housing 14 is inclined forward and downward, the inclination start line 50d that is the front edge of the front inclined wall 50b of the oil collecting recess 50 is also inclined forward, but the inclination start line 50d forms the rear in the horizontal direction. The angle β is set to 170 ° or less. Thus, even when the vehicle descends at the assumed maximum descending angle δ, the front inclined wall 50b of the oil collecting recess 50 is inclined downward by 10 ° or more toward the angular roller bearing 32, and the oil collecting The oil collected in the recess 50 can be smoothly supplied to the angular roller bearing 32.

Although the embodiments of the present invention have been described above, various design changes can be made without departing from the scope of the present invention.

For example, the bearing of the present invention is not limited to the angular roller bearing 32 of the embodiment, and may be any type of bearing.

The drive source of the present invention is not limited to the electric motor 11 of the embodiment, and may be another type of drive source such as an engine.

Claims

The gear case (16, 17), the differential gear (13) housed in the front part of the gear case (16, 17), and the differential gear (13) are supported on the side wall (17a) of the gear case (16, 17). Bearing (32), a final driven gear (29) provided on the outer periphery of the differential gear (13), and a driving force of a drive source (11) to the final driven gear (29) via an input shaft (20). A final drive gear (28) for transmitting, and the final driven gear (29) is a vehicle power transmission device disposed on the front side in the vehicle traveling direction with respect to the input shaft (20),
The final driven gear (29) is scraped from the bottom of the gear case (16, 17) to the side wall (17a) in front of the meshing portion (38) of the final driven gear (29) and the final drive gear (28). An oil collecting recess (50) for collecting the collected oil and supplying it to the bearing (32) is provided.
An oil guide wall (16c) arranged along the rear lower part of the final driven gear (29) is provided, and the meshing part (38) is horizontally aligned with the oil collecting recess (50) and the oil guide wall (16c). The vehicle power transmission device according to claim 1, wherein the vehicle power transmission device is located between the two.
An oil pump (45) is provided below the gear case (16, 17), and the oil guide wall (16c) includes a first space (47) for housing the final driven gear (29) and the oil pump (45). The vehicle power transmission device according to claim 2, wherein the vehicle power transmission device is disposed between the second space and the second space.
The oil level of the oil staying at the bottom of the gear case (16, 17) is located below the upper end of the oil guide wall (16c), and the first space (47) is located below the oil guide wall (16c). 4. The vehicle power transmission device according to claim 3, wherein an opening (49) that communicates with the second space (48) is formed. 5.
The vehicle power transmission device according to claim 4, wherein the opening (49) is located above a lower end of the final driven gear (29).
A motor case (15) that houses the electric motor (11) as the drive source is coupled to the gear case (16, 17), and the internal space of the motor case (15) and the gear case (16, 17) The communication hole (16b) for communicating the internal space is formed below the oil level of the oil staying at the bottom of the gear case (16, 17). The vehicle power transmission device according to claim 1.
The oil collecting recess (50) disposed in front of the center of the final driven gear (29) includes a bottom wall (50a) extending radially inward toward the bearing (32), and the bottom wall (50a). ) And the front inclined wall (50b) inclined at the first inclination angle (θ1) and the rear inclined wall connected to the rear side of the bottom wall (50a) and inclined at the second inclination angle (θ2). The first inclination angle (θ1) is smaller than the first inclination angle (θ1), and the second inclination angle (θ2) is smaller than the first inclination angle (θ1). The vehicle power transmission device according to claim 1.
The vehicle power transmission device according to claim 7, wherein the width of the bottom wall (50a) decreases toward the bearing (32).
The angle (α) formed by the inclination start line (50e) of the rear inclined wall (50c) constituting the rear edge of the groove-shaped cross section with respect to the rear in the horizontal direction is 90 ° when the vehicle climbs at the maximum climb angle. The angle (β) formed by the inclination start line (50d) of the front inclined wall (50b) constituting the front edge of the groove-shaped cross section with respect to the rear in the horizontal direction is the maximum downhill angle of the vehicle. The vehicle power transmission device according to claim 7, wherein the vehicle power transmission device is set to be 170 ° or less when descending at a slope.