CN113446386A

CN113446386A - Lubricating structure for vehicle power transmission device

Info

Publication number: CN113446386A
Application number: CN202110301249.6A
Authority: CN
Inventors: 河合则和; 深水信贵; 金瀬拓人
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2020-03-25
Filing date: 2021-03-22
Publication date: 2021-09-28
Also published as: JP7051926B2; JP2021156324A

Abstract

The invention provides a lubrication structure of a power transmission device for a vehicle, which can effectively lubricate a transfer case device and a front differential device under the condition of not increasing oil quantity. A lubrication structure for a power transmission device (PT) for a vehicle, wherein a transmission (3) including a final driven gear (44) and a final drive gear (30) and a transfer device (5) including a transfer input gear (52) are housed in a case (61), the transfer input gear (52) meshes with the final driven gear (44) at a position above a rotation center, and the case (61) is provided with a lubrication guide section (62) that guides oil stirred up by the final drive gear (30) to a bearing (42), wherein the lubrication guide section (62) includes: a first rib (62a) extending toward the axial center of the final driven gear (44); and a second rib (62b) extending toward the final drive gear (30) continuously with the first rib (62 a).

Description

Lubricating structure for vehicle power transmission device

Technical Field

The present invention relates to a lubrication structure of a vehicle power transmission device mounted on a four-wheel drive vehicle (4WD (4wheels drive)).

Background

In a transmission (transmission) of a vehicle power transmission device for transmitting a driving force of a driving source such as an engine or an electric motor to wheels, a case (case) houses various rotating members such as gears, and as a lubrication method thereof, an oil bath (oil bath) method may be used in which oil for lubrication stored in a bottom portion of the case is stirred up by rotation of the rotating members and the stirred oil lubricates each portion.

In addition, there is a four-wheel drive vehicle (4WD vehicle) that travels by transmitting the driving force of a driving source disposed at the front portion to left and right front wheels and left and right rear wheels, respectively, and a power transmission device of this type of four-wheel drive vehicle is provided with a transfer (transfer) device that transmits the driving force from a front differential device to a rear differential device, and the transfer device is connected to the rear differential device via a propeller shaft (propeller shaft). Here, the front differential device is a device that distributes and transmits driving force to the left and right front wheels, and the rear differential device is a device that distributes and transmits driving force to the left and right rear wheels.

Further, some transmissions for such four-wheel drive vehicles include a transfer case device disposed above a front differential device (see, for example, patent document 1).

[ Prior art documents ]

[ patent document ]

[ patent document 1] Japanese patent No. 6636877 publication

Disclosure of Invention

[ problems to be solved by the invention ]

In addition, in the four-wheel drive vehicle, it is necessary to lubricate the transfer device and the front differential device with oil stirred up by the rotating member housed in the case of the transmission of the power transmission device. In this case, in the power transmission device including the transmission in which the transfer device is disposed above the front differential device, the amount of oil tends to be insufficient in the transmission of the two-wheel drive vehicle (2WD) and the four-wheel drive vehicle in which the transfer device is disposed below the front differential device.

Therefore, a measure for increasing the amount of oil is considered, but if the amount of oil is increased, the pulling loss (stirring resistance) due to the viscosity of the oil when the rotating member stirs up the oil becomes large, which causes deterioration of fuel consumption rate or increase in weight.

The present invention has been made in view of the above problems, and an object thereof is to provide a lubrication structure of a power transmission device for a vehicle, which can effectively lubricate a transfer case device and a front differential device without increasing the amount of oil.

[ means for solving problems ]

In order to achieve the above object, the present invention provides a lubricating structure for a vehicle power transmission device PT, in which a case 61 having oil stored in a bottom portion thereof accommodates: a transmission 3 including a final driven gear 44 and a final drive gear 30 meshed with the final driven gear 44, the final driven gear 44 being rotatably supported by the housing 61 through a bearing 42; and a transfer device 5 including a transfer input gear 52 that meshes with the final driven gear 44, the transfer input gear 52 meshing with the final driven gear 44 at a position above a rotation center of the final driven gear 44, wherein a lubrication guide 62 is provided in the housing 61, the lubrication guide 62 being located above the bearing 42 and guiding oil stirred up by the final drive gear 30 or the transfer input gear 52 to the bearing 42, and the lubrication guide 62 includes: a first rib 62a extending toward the shaft center of the final driven gear 44; and a second rib 62b extending toward the final drive gear 30 continuously with the first rib 62 a.

According to the present invention, since the oil stirred up by the final drive gear, the final driven gear, and the transfer input gear is guided to the bearing supporting the final driven gear by the first rib and the second rib of the lubrication guide portion, the lubrication of the bearing by the oil is effectively performed.

Here, it is desirable that the second rib 62b extends from a portion continuous with the first rib 62a toward a position above the axial center of the final drive gear 30.

According to the above configuration, the oil stirred up by the final drive gear and dropped while hitting the upper inner peripheral surface of the housing is received by the second rib, and the oil is guided to the bearing of the final driven gear, so that the bearing can be lubricated efficiently by the oil.

It is preferable that the parking mechanism 10 is accommodated in the housing 61, a guide portion 61a for attaching a part of the parking mechanism 10 is disposed above the bearing 42 in the housing 61, and the second rib 42 is disposed between the guide portion 61a and the final driven gear 44 in the vertical direction.

According to the above configuration, the oil stirred up by the final drive gear and the oil scattered by the rotation of the other gear collide with the guide portion and fall toward the second rib, and the oil is guided by the second rib and supplied to the bearing of the final driven gear, so that the bearing can be lubricated more effectively.

Further, the following structure may be adopted: a first oil reservoir 73 is provided above the transfer input gear 52 of the housing 61, a guide wall 64 extending toward the central axis of the final driven gear 44 is provided between the first oil reservoir 73 and the bearing 42, and an end of the guide wall 64 on the first oil reservoir 73 side faces an end of the first oil reservoir 73 on the guide wall 64 side, so that the oil of the first oil reservoir 73 is guided to the bearing 42 via the guide wall 64.

According to the above structure, the oil that is stirred up by the rotation of the transfer input gear and flows into the first oil reservoir is guided from the first oil reservoir to the bearing via the guide wall, so the bearing can be lubricated more effectively.

Further, the guide wall 64 may be disposed in the second oil reservoir 63 communicating with the first oil reservoir 73, and the guide wall 64 may constitute a flat plate-shaped partition plate 64a, and the partition plate 64a may divide the second oil reservoir 63 into two spaces S1, S2, and may receive and guide the oil flowing into the respective spaces S1, S2 toward the bearing 42.

According to the above configuration, the flow of the oil which is stirred up by the transfer input gear and the final driven gear and stored in the second oil storage portion can be divided by the partition plate of the guide wall, and the oil is supplied to the bearing of the final driven gear, so that the bearing can be lubricated more effectively.

It is preferable that a discharge plate 64b is provided at an end of the guide wall 64 on the bearing 42 side, and the discharge plate 64b covers a part of the opening of the second oil reservoir 63 and discharges the oil stored in the second oil reservoir 63 toward the bearing 42 from an axial gap δ with the wall surface of the housing 61.

According to the above configuration, the oil stored in the oil storage portion and flowing through the partition wall of the guide wall is received by the discharge plate of the guide wall, and the oil is discharged from the axial gap between the discharge plate and the wall surface of the housing toward the bearing of the final driven gear, so that the bearing is lubricated more effectively with the oil.

Further, it is desirable that the guide wall 64 is disposed on the opposite side of the lubrication guide 62 from the final drive gear 30.

According to the above configuration, the oil stirred up by the final drive gear flows into the oil reservoir and is efficiently stored in the oil reservoir, and the stored oil is supplied to the bearing of the final driven gear through the lubrication guide portion, so that the bearing is efficiently lubricated by the oil.

The transfer case input gear 52 may be supported by a transfer case cover 57 via a bearing 58, the transfer case cover 57 may be provided with a receiving portion for receiving the bearing 58, the receiving portion may be formed with a notch groove 57b, the notch groove 57b may be disposed at a position facing a meshing portion between the final driven gear 44 and the transfer case input gear 52 or at a position above the position facing the meshing portion, and the first oil reservoir 73 of the housing 61 may be provided with a communication hole 57a for guiding oil between the transfer case cover 57 and the housing 61.

According to the above configuration, the transfer device can be lubricated by guiding the oil in the first oil reservoir into the transfer case cover from the communication hole, and the return oil returned from the transfer case cover through the notch groove can be stirred up by the meshing portion of the final driven gear and the transfer input gear and sent to the first oil reservoir again. Therefore, efficient lubrication of the transfer device and the like can be achieved.

[ Effect of the invention ]

According to the present invention, the following effects can be obtained: the transfer case device and the front differential device of the power transmission device for a vehicle can be effectively lubricated without increasing the amount of oil.

Drawings

Fig. 1 is a plan view showing a basic structure of a power transmission system of a four-wheel drive vehicle.

Fig. 2 is a skeleton diagram showing a basic structure of a vehicle power transmission device including a lubricating structure of the present invention.

Fig. 3 is a partial side view showing a structure of a side of the transmission case where the side is joined to the torque converter case.

Fig. 4 is a partial side view showing a structure of an engagement surface side of the transmission case and the torque converter case with various gears removed.

Fig. 5 is a partial side sectional view showing a state in which the transmission case is cut inward in the vertical direction of the paper of fig. 4.

Fig. 6 is a partial side sectional view showing a structure of an engagement surface side of the torque converter case with the transmission case.

Fig. 7 is a sectional view taken along line a-a of fig. 6.

Fig. 8 is an enlarged detail view of part B of fig. 7.

Fig. 9 is a diagram for explaining the flow of oil, and the flow of oil is added to fig. 5.

Fig. 10 is a diagram for explaining the flow of oil, and the flow of oil is additionally described in fig. 6.

[ description of symbols ]

1: crankshaft

3: speed variator

4: front differential device

5: transfer case device

6: rear differential device

9: transmission shaft

10: parking mechanism

16: support member for parking mechanism

30: final drive gear

42: bearing assembly

44: final driven gear

52: transfer case input gear

57: transfer case cover body

57 a: communicating hole

57 b: oil circuit (notch groove)

61: transmission housing

61A: longitudinal wall of transmission housing

61 a: guide part of transmission housing

62: lubrication guide

62 a: first rib

62 b: second rib

63: second oil reservoir

64: beam board (guide wall)

64 a: beam board partition

64 b: discharge plate of beam plate

71: torque converter shell

73: the first oil reservoir

100: four-wheel drive vehicle

PT: power transmission device

S1, S2: space of oil reservoir

δ: axial clearance

Detailed Description

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

[ basic Structure of Power Transmission device for vehicle ]

Fig. 1 is a plan view showing a basic structure of a power transmission system of a four-wheel drive vehicle, and fig. 2 is a skeleton view showing a basic structure of a vehicle power transmission device including a lubricating structure of the present invention.

In the four-wheel drive vehicle 100 shown in fig. 1, an engine E as a drive source is disposed at a front portion (upper portion in fig. 1), a torque converter 2 and a transmission 3 are connected in order to a crankshaft 1 as an output shaft of the engine E, and the engine E, the torque converter 2, and the transmission 3 are mounted at a front portion of a vehicle body in a state of being arranged side by side in a vehicle width direction (left-right direction in fig. 1).

The power transmission device PT that transmits the driving force of the engine E to the left and right front wheels WFL, WFR and the left and right rear wheels WRL, WRR includes: a torque converter 2, a transmission 3 connected to the torque converter 2, a front differential device 4 connected to the transmission 3, a transfer device 5 connected to the front differential device 4, and a rear differential device 6 connected to the transfer device 5.

The front differential device 4 is connected to left and right front wheels WFL, WFR via left and right

front axles

7L, 7R, and the rear differential device 6 is connected to left and right rear wheels WRL, WRR via left and right

rear axles

8L, 8R. The rear differential device 6 is connected to the transfer case device 5 via a propeller shaft 9 disposed along the vehicle front-rear direction (vertical direction in fig. 1).

As shown in fig. 2, in the transmission 3, a main shaft MS extending in the vehicle width direction, a counter shaft SS, and an intermediate shaft CS are disposed in parallel with each other so as to be rotatable. The main drive gear 21 is fixed to the main shaft MS, and the main three-speed gear 22 that can be coupled to the main shaft MS by the three-speed clutch C3, and the main four-speed gear 23 and the main reverse gear 24 that can be coupled to the main shaft MS by the four-speed-reverse clutch C4R are supported so as to be relatively rotatable.

The counter shaft SS is fixed with a counter driven gear 25, and is supported so as to be relatively rotatable with respect to a first speed gear 26 that can be coupled to the counter shaft SS by a first speed clutch C1 and a second speed gear 27 that can be coupled to the counter shaft SS by a second speed clutch C2.

The intermediate second-speed gear 28, the intermediate third-speed gear 29, and the final drive gear 30 are fixed to the intermediate shaft CS, and the intermediate idle gear 31, the intermediate fourth-speed gear 32, and the intermediate reverse gear 33 are supported so as to be rotatable relative to each other. Further, the intermediate shaft CS is supported so as to be relatively rotatable by an intermediate first speed gear 34 that can be coupled to the intermediate shaft CS via a first speed holding clutch CLH.

Here, the reverse idler gear 35 meshes with the main reverse gear 24 and the intermediate reverse gear 33. The intermediate first speed gear 34 can be coupled to the intermediate third speed gear 29 by the one-way clutch COW, and the intermediate fourth speed gear 32 and the intermediate reverse gear 33 can be selectively coupled to the intermediate shaft CS by the selector 36.

The main drive gear 21 meshes with the intermediate idle gear 31, and the intermediate idle gear 31 meshes with the sub driven gear 25. Therefore, the rotation of the crankshaft 1 of the engine E is transmitted to the counter shaft SS via the torque converter 2, the main shaft MS, the main drive gear 21, the intermediate idle gear 31, and the sub driven gear 25.

When the first speed clutch C1 couples the counter shaft SS to the second speed gear 26 rotatably supported on the counter shaft SS, the rotation of the counter shaft SS is transmitted to the intermediate shaft CS via the first speed clutch C1, the second speed gear 26, the one-way clutch COW, and the third intermediate gear 29, and the first speed gear is established. The first-speed clutch C1 is maintained in the engaged state even when the second to fourth speed gears are established, but the one-way clutch COW slips (slip) when the second to fourth speed gears are established.

When the second clutch C2 couples the counter shaft SS to the sub second-speed gear 27 supported by the counter shaft SS in a relatively rotatable manner, the rotation of the counter shaft SS is transmitted to the intermediate shaft CS via the second clutch C2, the sub second-speed gear 27, and the intermediate second-speed gear 28, and the second speed gear is established.

When the main third gear 22 supported by the main shaft MS so as to be relatively rotatable is coupled to the main shaft MS by the third clutch C3, the rotation of the main shaft MS is transmitted to the intermediate shaft CS via the third clutch C3, the main third gear 22, and the intermediate third gear 29, and a third speed gear is established.

When the main four-speed gear 23 supported by the main shaft MS so as to be relatively rotatable is coupled to the main shaft MS by the four-speed-reverse clutch C4R in a state where the intermediate four-speed gear 32 supported by the intermediate shaft CS so as to be relatively rotatable is coupled to the intermediate shaft CS by the selector 36, the rotation of the main shaft MS is transmitted to the intermediate shaft CS via the four-speed-reverse clutch C4R, the main reverse gear 24, the reverse idler gear 35, the intermediate reverse gear 33, and the selector 36, and the fourth-speed gear stage is established.

When the main reverse gear 24 supported by the main shaft MS so as to be relatively rotatable is coupled to the main shaft MS by the four-speed-reverse clutch C4R in a state where the intermediate reverse gear 33 supported by the intermediate shaft CS so as to be relatively rotatable is coupled to the intermediate shaft CS by the selector 36, the rotation of the main shaft MS is transmitted to the intermediate shaft CS via the four-speed-reverse clutch C4R, the main reverse gear 24, the reverse idler gear 35, the intermediate reverse gear 33, and the selector 36, and a reverse gear is established.

When the first speed holding clutch CLH is engaged with the first speed clutch C1 engaged, the first speed holding gear stage is established. If the first-speed-maintaining gear position is established when strong engine braking is required, even if the one-way clutch COW slips, the torque of the rear wheels WRL and WRR can be transmitted in reverse to the engine E via the first-speed-maintaining clutch CLH.

Next, the structure of the front differential device 4 will be explained.

As shown in fig. 2, the front differential device 4 includes a differential case 41 rotatably supported by a transmission case (see fig. 3)61 described later via a bearing 42, and a large-diameter final driven gear 44 is fixed to an outer periphery of the differential case 41. Here, the final driven gear 44 meshes with the final drive gear 30 fixed to the counter shaft CS. Since the configurations of the front differential device 4 and the rear differential device 6 are well known, detailed descriptions thereof will be omitted.

In the transmission 3, the rotation of the intermediate shaft CS is transmitted to the differential case 41 via the final drive gear 30 and the final driven gear 44, and the rotation of the differential case 41 is transmitted to the left and right

front axles

7L and 7R in accordance with the load of the left and right front wheels WFL and WFR, so that the left and right front wheels WFL and WFR are rotationally driven.

Next, the structure of the actuator device 5 will be explained.

In the transfer device 5, a transfer input gear 52 and a first bevel gear 53 are formed at both axial ends of a transfer input shaft 51 rotatably arranged in the vehicle width direction, respectively, and the transfer input gear 52 meshes with the final driven gear 44 of the front differential device 4. The first bevel gear 53 meshes with a second bevel gear 55 fixed to one end (front end) in the axial direction of a transfer output shaft 54, and the transfer output shaft 54 is arranged in the vehicle front-rear direction and is rotatable. The other end (rear end) of the transfer output shaft 54 is connected to the propeller shaft 9 shown in fig. 1 by a joint (not shown).

Therefore, the rotation transmitted from the engine E to the final driven gear 44 of the front differential device 4 is transmitted to the rear differential device 6 shown in fig. 1 via the transfer input gear 52, the transfer input shaft 51, the first bevel gear 53, the second bevel gear 55, the transfer output shaft 54, and the propeller shaft 9, and is distributed to the left and right

rear axles

8L, 8R in the rear differential device 6, so that the left and right rear wheels WRL, WRR are rotationally driven. As a result, the four-wheel drive vehicle 100 shown in fig. 1 travels by the rotation of the left and right front wheels WFL, WFR and the left and right rear wheels WRL, WRR.

[ lubricating structure of Power Transmission device ]

Next, a lubrication structure of the power transmission device according to the present invention will be described below with reference to fig. 3 to 8.

Fig. 3 is a partial side view showing a structure of an engagement surface side of a transmission case with a torque converter case, fig. 4 is a partial side view showing a structure of an engagement surface side of the transmission case with the torque converter case with various gears removed, fig. 5 is a partial side sectional view showing a state where the transmission case is cut inward in a direction perpendicular to a paper surface of fig. 4, fig. 6 is a partial side sectional view showing a structure of an engagement surface side of the torque converter case with the transmission case, fig. 7 is a sectional view taken along a line a-a of fig. 6, and fig. 8 is an enlarged detail view of a portion B of fig. 7.

The case housing the transmission 3, the front differential device 4, and the transfer device 5 shown in fig. 2 is configured by joining the transmission case 61 shown in fig. 3 and the torque converter case 71 shown in fig. 6, and joining and integrating both by a plurality of bolts, not shown.

As shown in fig. 3, a large-diameter final driven gear 44, and a small-diameter final drive gear 30 and a transfer input gear 52 that mesh with the final driven gear 44 are disposed on the side of the transmission case 61 that is joined to the torque converter case 71. The parking mechanism 10 is disposed above the final driven gear 44 and the final drive gear 30. Further, lubricating oil is stored in the bottom portions of the transmission case 61 and the torque converter case 71, and a part of the final driven gear 44 is immersed in the oil. Here, the transfer input gear 52 meshes with the final driven gear 44 at a position above the rotation center P of the final driven gear 44.

The parking mechanism 10 includes a parking lever 12, a parking rod 13, a parking gear 14, and the like, the parking column 12 is rotatably supported by a vertical wall (a wall on the inner side of the paper surface of fig. 3) 61A of a transmission case 61 via a shaft 11, the parking rod 13 slides in the vehicle width direction (the direction perpendicular to the paper surface of fig. 3) via an actuator (not shown), and the parking gear 14 is coupled to a counter shaft CS. Here, a plurality of (6 in the illustrated example) engagement grooves 14a are formed at equal angular (60 °) intervals in the circumferential direction on the outer periphery of the parking gear 14. An engagement claw 12a is formed at one end of the parking lever 12, and the parking lever 12 is biased in the unlocking direction (the direction in which the engagement claw 12a is disengaged from the engagement groove 14a of the parking gear 14) by a return spring 15 wound around the shaft 11. Further, at an end portion of the parking rod 13, a truncated cone shaped cam 13a that engages with the other end 12b of the parking rod 12 is provided.

Further, a boss (boss) -shaped guide portion (mount seat) 61A for mounting a support member 16 is integrally formed on an upper portion of the vertical wall 61A of the transmission case 61 (above the bearing 42 supporting the final driven gear 44), and the support member 16 supports the parking rod 13 of the parking mechanism 10.

As shown in fig. 4 and 5, a lubrication guide 62 bent in an inverted L shape is integrally formed on the transmission case 61 at a position close to the upper guide 61a and above the bearing 42. The lubrication guide 62 is located above the bearing 42 (see fig. 2), functions to guide oil stirred up by the transfer input gear 52 or oil scattered by the rotation of the final drive gear 30 to the bearing 42, and includes: a first rib 62a extending toward the shaft center of the final driven gear 44; and a second rib 62b extending toward the final drive gear 30 continuously with the first rib 62 a. Here, the second rib 62b extends from a portion continuous with the first rib 62a toward a position above the axial center of the final drive gear 30, and is disposed between the guide portion 61a and the final driven gear 44 in the vertical direction.

As shown in fig. 4 and 6, a first oil reservoir 73 is provided between the transmission case 61 and the torque converter case 71 and above the transfer input gear 52. The first oil reservoir 73 is a space separated from the transfer input gear 52 by a substantially circular-arc rib 65 (see fig. 4) and a rib 75 (see fig. 6) along a part of the upper side of the transfer input gear 52. Further, a second oil reservoir 63 is provided between the transmission housing 61 and the torque converter housing 71 and between the first oil reservoir 73 and the center of the final driven gear 44 and the bearing 42. As shown in fig. 4 and 5, a beam plate (garter plate)64 constituting a guide wall is provided in the second oil reservoir 63.

The beam plate 64 performs the following functions: the oil that is stirred up by the final driven gear 44, the final drive gear 30, and the transfer input gear 52 and flows into the first oil reservoir 73 and the second oil reservoir 63 from three directions is received and guided to the bearing 42. The beam plate 64 is disposed on the opposite side (left side in fig. 4 and 5) of the final drive gear 30 with respect to the first rib 62a and the second rib 62b constituting the lubrication guide 62.

That is, one end portion of the beam plate 64 (the transfer input gear 52 and the end portion on the first oil reservoir 73 side) constitutes a flat plate-shaped partition plate 64a, and the partition plate 64a extends from the end portion of the first oil reservoir 73 toward the central axis of the final driven gear 44, and divides the second oil reservoir 63 into two spaces S1, S2 in the up-down direction. The partition plate 64a performs the following functions: the oil flowing into the spaces S1 and S2 is received and guided toward the bearing 42 (see fig. 2) of the final driven gear 44. Further, a discharge plate 64b having a curved arc shape is formed at the other end portion (end portion on the side of the final driven gear 44 and the bearing 42) of the beam plate 64, and the discharge plate 64b covers a part of the opening portion of the second oil reservoir 63 and discharges the oil stored in the second oil reservoir 63 toward the bearing 42 from an axial gap δ between the oil and the wall surface of the vertical wall 61A of the transmission case 61. The discharge plate 64b is integrally formed at one end of the partition plate 64a so as to be orthogonal to the partition plate 64 a.

As shown in fig. 6, the first oil reservoir 73 formed above the transfer input gear 52 communicates with the space S shown in fig. 7 via a communication hole 74 formed in the torque converter case 71.

Here, as shown in fig. 7, in the transfer device 5, a first bevel gear 53, a second bevel gear 55, and the like that mesh with each other are housed in a transfer case 56 and a transfer cover 57 attached to the transfer case 56. The transfer input shaft 51 formed with the first bevel gear 53 and the transfer output shaft 54 formed with the second bevel gear 55 are rotatably supported by a transfer cover 57 and a transfer case 56 via a bearing (tapered roller bearing) 58 and a bearing (tapered roller bearing) 59, respectively, and the space S is formed between the torque converter case 71 and the transfer cover 57.

As shown in fig. 8, a communication hole 57a for communicating the space S with the inside of the transfer case cover 57 is formed in the side portion of the transfer case cover 57. In addition, an L-shaped bent oil passage (notch groove) 57b is formed in a portion of the transfer case cover 57 that supports one of the bearings 58 (lower portion in fig. 8), and the inside of the transfer case cover 57 and the inside of the transmission case 61 communicate with each other through the oil passage 57 b. As shown in fig. 6, the outflow end (outflow port) of the oil passage 57b is disposed at a position (facing position) facing the meshing portion between the final driven gear 44 and the transfer input gear 52 in the torque converter case 71.

Next, the flow of oil in the lubrication structure configured as described above will be described. Fig. 9 and 10 are views for explaining the flow of oil, and the flow of oil is additionally described in fig. 5 and 6, respectively. According to the lubrication structure configured as described above, oil flowing in the following three modes [ 1] to [ 3 ] can be efficiently supplied to the bearing 42.

The oil stirred up by the final driven gear 44 is blocked by the beam plate 64 and supplied to the bearing 42.

The oil that is stirred up by the transfer input gear 52 and guided to the first oil reservoir 73 is guided by the beam plate 64 and supplied to the bearing 42.

The oil scattered by the rotation of the gears (the final drive gear 30 and the like) other than the final driven gear 44 is guided by the inner surfaces (inner walls) of the transmission case 61 and the torque converter case 71 and the beam plate 64, and is supplied to the bearing 42.

The flow of oil in each mode will be described in detail below.

First, in the mode [ 1], the oil is stirred up along the arrow a of fig. 9 by the rotating final driven gear 44, but the oil flows into one of the spaces S1 of the second oil reservoir 63. In this case, when the rotation speed of the final driven gear 44 is low, as indicated by an arrow a1, the oil is not collided with the partition plate 64a of the beam plate 64 and is blocked by the discharge plate 64b, and the oil is discharged from the axial gap δ formed between the discharge plate 64b and the vertical wall 61A of the transmission case 61, falls toward the bearing 42 of the final driven gear 44, and is supplied to the bearing 42 for lubrication.

On the other hand, when the rotational speed of the final driven gear 44 is high, as shown by an arrow a2 in fig. 9, the oil stirred up by the final driven gear 44 collides with the partition plate 64a of the beam plate 64. The oil that has collided with the partition plate 64a changes its direction, is received by the discharge plate 64b of the beam plate 64, is discharged from the axial gap δ formed between the discharge plate 64b and the vertical wall 61A of the transmission case 61 in the same manner as described above, falls toward the bearing 42 of the final driven gear 44, and is supplied to the bearing 42 for lubrication.

In the mode [ 2 ], as shown by an arrow b1 in fig. 10, the oil stirred up by the transfer input gear 52 that meshes with the final driven gear 44 and rotates in the arrow direction (clockwise direction) in fig. 10 flows into the first oil reservoir 73. The oil that has flowed into the first oil reservoir 73 is transferred from the end portions of the first oil reservoir 73 that face each other to the end portion of the beam plate 64, as shown by arrow b2 in fig. 9, and flows into the second oil reservoir 63. The oil flowing into the second oil reservoir 63 flows along the partition plate 64a of the beam plate 64, is received by the discharge plate 64b of the beam plate 64 in the same manner as described above, is discharged from the axial gap δ formed between the discharge plate 64b and the vertical wall 61A of the transmission case 61, falls toward the bearing 42 (see fig. 2) of the final driven gear 44, and is supplied to the bearing 42 for lubrication.

Further, a part of the oil in the first oil reservoir 73 flows into a space (a space between the torque converter case 71 and the transfer case cover 57) S shown in fig. 7 from the communication hole 74 opened in the first oil reservoir 73. As shown in detail in fig. 8, the oil flowing into the space S flows into the transfer case cover 57 from the communication hole 57a formed in the transfer case cover 57 to lubricate the respective parts, and then flows into the transmission case 61 through the L-shaped oil passage 57b formed in the transfer case cover 57. At this time, the outflow end of the oil passage 57b is disposed at a position facing the meshing portion of the final driven gear 44 and the transfer input gear 52, so that the oil (return oil from the transfer device 5) flowing out of the oil passage 57b is stirred up by the rotation of the final driven gear 44 and the transfer input gear 52, and flows into the first oil reservoir 73 again as shown by an arrow b1 in fig. 10. In the present embodiment, the case where the outflow end of the oil passage 57b is disposed at a position facing the meshing portion between the final driven gear 44 and the transfer case input gear 52 is shown, but otherwise, although not shown, the outflow end of the oil passage 57b may be disposed at a position above the position facing the meshing portion between the final driven gear 44 and the transfer case input gear 52.

In the mode [ 3 ], the oil scatters as indicated by an arrow c1 in fig. 9 due to the rotation of the final drive gear 30 meshing with the final driven gear 44. The oil hits the upper inner peripheral surface of the transmission case 61 or the guide portion 61a and drops, and flows into the space S2 of the second oil reservoir 63 as indicated by an arrow c2 in fig. 9. In addition, a part of the dropped oil is received by the second rib 62b of the lubrication guide 62. Then, the oil received by the second rib 62b also flows into the space S2 of the second oil reservoir 63 along the second rib 62b while being guided by the first rib 62 a. Then, the oil that has flowed into the space S2 of the second oil reservoir 63 is redirected by the partition plate 64a of the beam plate 64, flows toward the discharge plate 64b, and is stopped by the discharge plate 64 b. The oil received by the discharge plate 64b is discharged from the axial gap δ formed between the discharge plate 64b and the vertical wall 61A of the transmission case 61, falls toward the bearing 42 of the final driven gear 44, and is supplied to the bearing 42 for lubrication.

As described above, in the present embodiment, since the oil stirred up by the final driven gear 44, the final drive gear 30, and the transfer input gear 52 is collected into the second oil reservoir 63 from three directions, and is supplied from the second oil reservoir 63 to the bearing 42 of the final driven gear 44 to lubricate the bearing 42, and a part of the oil is supplied to the transfer device 5 to lubricate the transfer device 5, the following effects are obtained: the transfer case device 5 and the front differential device 4 of the power transmission device PT can be lubricated efficiently without increasing the amount of oil.

The application of the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical ideas described in the claims, the specification, and the drawings.

Claims

1. A lubrication structure of a power transmission device for a vehicle, characterized in that:

a case having oil stored in the bottom thereof accommodates:

a transmission, comprising: a final driven gear and a final drive gear meshed with the final driven gear, the final driven gear being rotatably supported by the housing through a bearing; and

transfer case device, comprising: a transfer case input gear meshed with the final driven gear,

wherein the transfer case input gear is meshed with the final driven gear at a position above a rotation center of the final driven gear,

a lubrication guide portion is provided in the housing, the lubrication guide portion being located above the bearing and guiding oil stirred up by the final drive gear or the transfer case input gear toward the bearing,

the lubrication guide portion includes:

a first rib extending toward a shaft center of the final driven gear; and

a second rib extending toward the final drive gear continuously with the first rib.

2. The lubrication structure of a vehicular power transmitting apparatus according to claim 1,

the second rib extends from a portion continuous with the first rib toward a position above a shaft center of the final drive gear.

3. The lubrication structure of a vehicular power transmitting apparatus according to claim 1,

a parking mechanism is accommodated in the housing,

a guide portion for mounting a part of the parking mechanism, disposed above the bearing in the housing,

the second rib is disposed between the guide portion and the final driven gear in the vertical direction.

4. The lubrication structure of a vehicular power transmitting apparatus according to claim 1,

a first oil reservoir is provided above the transfer case input gear of the housing,

a guide wall extending toward a central axis of the final driven gear is provided between the first oil reservoir and the bearing,

an end portion of the guide wall on the first oil reservoir side, an end portion of the guide wall side facing the first oil reservoir,

so that the oil of the first oil reservoir is guided to the bearing via the guide wall.

5. The lubrication structure of a vehicular power transmitting apparatus according to claim 4,

the guide wall is disposed in a second oil reservoir portion communicating with the first oil reservoir portion,

the guide wall constitutes a flat plate-like partition plate that divides the second oil reservoir into two spaces, receives oil that flows into each space, and guides the oil toward the bearing.

6. The lubrication structure of a vehicular power transmitting apparatus according to claim 5,

a discharge plate is provided at the bearing-side end of the guide wall,

the discharge plate covers a part of the opening of the second oil reservoir, and discharges the oil stored in the second oil reservoir toward the bearing from an axial gap between the discharge plate and the wall surface of the housing.

7. The lubrication structure of the vehicular power transmitting apparatus according to any one of claims 4 to 6, characterized in that,

the guide wall is disposed on the opposite side of the lubrication guide from the final drive gear.

8. The lubrication structure of the vehicular power transmitting apparatus according to any one of claims 4 to 6, characterized in that,

the transfer case input gear is supported by the transfer case cover via a bearing,

the transfer case cover body is provided with a containing part for containing the bearing,

a notch groove is formed in the housing portion, the notch groove being disposed at a position facing a meshing portion between the final driven gear and the transfer input gear or at a position above a position facing the meshing portion,

the first oil reservoir of the case is provided with a communication hole that guides oil between the transfer case lid and the case.