JPH06137408A - Transfer device - Google Patents

Abstract

PURPOSE:To reduce weight of an output shaft, and prevent with a simple structure generation of noises and seizure of an oil pump which may be caused by suctioning air or dusts from an oil strainer by arranging the oil strainer inside a hollow space of the output shaft on the bottom of a transfer case. CONSTITUTION:When a transfer device 1 is operated, an oil pump 1.5 is driven. Oil in an oil reservoir 83 is suctioned through an oil strainer 111, a flow passage 109 and a suction port 107. On the other hand, the oil discharged from the oil pump 15 is supplied to each lubrication portion of an input shaft 3, a center differential 5, a differential control device 7 and a rear wheel side output shaft 9 through a discharge port 117, flow passages 117 and 119. A hollow space 85 is formed on an axial center of an output shaft 11, while the oil strainer 111 is arranged inside the hollow space. It is thus possible to prevent agitation of the oil in the hollow space 85 even when the oil inside the oil reservoir 83 is agitated by a chain transmission mechanism 13, and to prevent suctioning of air or dusts from the oil strainer 111.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer device for a four-wheel drive vehicle.

[0002]

2. Description of the Related Art FIG. 3 is disclosed in Japanese Utility Model Publication No. 63-166757.
A lubricating structure applied to such a transfer device has been proposed.

In this case, the input shaft 705 of the transfer device 701 is arranged above the transfer case 703,
The front wheel side output shaft 707 is arranged at the bottom of the transfer case 703. Sprockets are respectively supported on the input shaft 705 and the output shaft 707, and the drive connection between them is made by a chain. An oil reservoir is formed at the bottom inside the transfer case 703, and an oil strainer 711 of the lubricating oil pump 709 is arranged at this bottom. The oil pump 709 sucks oil from the oil strainer 711 and lubricates a lubricated portion inside the transfer case 703.

The oil in the oil sump is the sprocket,
When the oil is splashed up by the operation of the chain or the like, the oil level is lowered, and the air mixed with the oil from the strainer 711 is sucked into the oil pump 709. In order to prevent this, in the above-mentioned proposal, a partition wall 71 is provided on the inner lower wall of the transfer case 703 where oil is accumulated so as to partition the phase between the oil strainer portion and the sprocket portion.
3 is provided so as to make a difference in oil level between the oil strainer portion and the sprocket portion, and to increase the oil level in the oil strainer portion. As a result, the intake of air from the oil strainer 711 is eliminated to prevent the generation of abnormal noise due to the intake of air and the seizure of the oil pump 709 due to insufficient oil.

[0005]

However, according to this method, since a plate serving as a partition wall and mounting bolts are required, the number of parts is increased, and the mounting work is complicated, and the oil strainer has a bottom portion inside the transfer case. Since it is arranged at the position, there arises a problem that dust in the oil is easily sucked.

The present invention has been made by paying attention to this point, and has a lightweight and inexpensive structure in which the number of parts is small and the mounting work is easy, so that the intake of air from the oil strainer is eliminated and abnormal noise due to the intake of air is produced. The purpose is to prevent the oil pump from seizing due to the occurrence of oil, oil shortage, and suction of dust.

[0007]

To this end, a transfer device of the present invention comprises a transfer case, an input shaft supported by the transfer case and receiving a driving force from an engine, and the transfer case supported by the transfer case. An output shaft which is arranged below the oil level of the input shaft and is driven to be connected to the input shaft; It is characterized in that it is arranged in a cavity provided in the core.

[0008]

With this configuration, even if the oil in the oil sump is agitated by the rotation of the output shaft, the oil in the cavity of the output shaft is not agitated. Therefore, there is no intake of air from the oil strainer, and it is possible to prevent generation of abnormal noise due to intake of air and seizure of the oil pump due to insufficient oil. Further, since the oil strainer is arranged apart from the bottom of the transfer case upward, easiness of sucking dust is eliminated.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment will be described with reference to FIG. This embodiment is a transfer device for a four-wheel drive vehicle.

First, the main structure and function of the transfer device 1 will be described.

The transfer device 1 includes an input shaft 3, a center differential 5, a differential limiting device 7, an output shaft 9 on the rear wheel side, an output shaft 11 on the front wheel side, and sprockets 5 on the input / output shafts 3 and 11.
A chain transmission mechanism 13 for transmitting a driving force between 3, 81,
A lubricating oil pump 15 and the like are provided.

The driving force of the engine is input to the center differential 5 via the transmission and the input shaft 3. The driving force divided by the center differential 5 is transmitted to the rear wheel side via the output shaft 9, and is also transmitted from the chain transmission mechanism 13 to the output shaft 1.
1 is transmitted to the front wheel side. The differential limiting device 7 limits the differential between the outputs (front and rear wheels) of the center differential 5. Also,
All of these components are housed in the transfer case 21. The transfer case 21 is divided into a front case 21a and a rear case 21b, and a bottom portion thereof forms an oil reservoir 83 of lubricating oil.

Next, each function will be described.

The input shaft 3 is provided with a flange 17 for connecting to the transmission side, the front end side is supported by the front case 21a via a bearing 19, and the rear end portion is supported by the center differential 5 via a bearing 23. It is supported by the differential case 25. The differential case 25 is formed integrally with the output shaft 9 on the rear wheel side. A flange 27 is spline-connected to the rear end of the output shaft 9 and is fixed by a nut 29. The flange 27 is connected to the propeller shaft on the rear wheel side.

The differential case 25 and the output shaft 9 are supported by the rear case 21b by bearings 31 and 33, respectively. Seals 35 and 37 are arranged between the transfer case 21 and the flanges 17 and 27, respectively.

The center differential 5 is housed in a differential case 25. The center differential 5 is of a planetary gear type and is provided with an internal gear 39, a pinion gear 41 and a sun gear 43 which are meshed in this order.

The internal gear 39 is formed on the differential case 25. The pinion gear 41 is the pinion shaft 4
5, the shaft 45 is rotatably supported, and both ends of the shaft 45 are supported by front and rear pinion carriers 47 and 49.
The carriers 47 and 49 are welded together. The sun gear 43 is formed on a hollow hub 50 through which the input shaft 3 penetrates. The hub 50 is supported on the input shaft 3 by a bearing 51.

The input shaft 3 is spline-connected to the rear pinion carrier 49, and the hub 50 is spline-connected to the drive-side sprocket 53 at the outer diameter portion of the front end thereof. This drive side sprocket 53 has bearings 5 at both ends.
It is supported by the transfer case 21 via 5, 57.

Therefore, the driving force from the engine is applied to the input shaft 3
Input from the pinion carrier 49 to the center differential 5 via the internal gear 39 (differential case 25) to the rear wheel side through the output shaft 9 and the sun gear 43 (drive side sprocket 53) through the output shaft 11 to the front wheel side. When the drive resistance difference is transmitted between the front and rear wheels, the pinion gear 41
The driving force is differentially distributed to each side of the front and rear wheels due to the rotation and the revolution of the vehicle.

On the front side of the center differential 5, a multi-plate type main clutch 6 connecting the differential case 25 and the hub 59 to each other.
1 is arranged, and this hub 59 is the sun gear 43 (hub 5
The front end side of 0) is spline-connected to this. At the front end of the main clutch 61, a pressing ring 63, which is engaged with the hub 59 so as to be movable back and forth, is arranged.

A ball cam 69 is formed via a ball 67 between the pressing ring 63 and a cam ring 65 arranged in front of the pressing ring 63. Cam ring 65 and differential case 2
A bearing 71 and a washer 73 that receive a cam thrust force are disposed between the bearing 5 and the bearing 5.

A multi-plate type pilot clutch 75 is further arranged between the cam ring 65 and the differential case 25. On the rear side of the clutch 75, an armature 77 engaged with the cam ring 65 so as to be movable back and forth is arranged. A ring-shaped electromagnet 79 is coaxially arranged on the front side of the differential case 25 and fixed to the transfer case 21.

When an exciting current is supplied to the electromagnet 79, the armature 77 is attracted and the pilot clutch 75 is engaged, and the cam ring 65 is connected to the differential case 25 via the clutch 75. On the other hand, since the cam ring 65 is connected to the sun gear 43 side via the ball cam 69 and the pressing ring 63, the differential between the internal gear 39 and the sun gear 43 is limited according to the engagement force (slip) of the clutch 75, and the center differential 5 is moved. The differential limitation of is performed.

When the cam ring 65 is connected to the differential case 25 via the clutch 75, a differential torque between the internal gear 39 of the center differential 5 and the sun gear 43 is applied to the ball cam 69, and the rearward cam thrust force generated causes the pressing ring. 63 moves, the main clutch 61 is engaged, and the differential between the gears 39 and 43 is limited. Thus
A large differential limiting force is obtained by adding the engaging force of the clutch 61 to the engaging force of the clutch 75.

The pilot clutch 75 is driven by the electromagnet 79.
When the slip of the ball cam 69 is adjusted, the engaging force of the main clutch 61 changes due to the change of the differential torque applied to the ball cam 69.
The differential limiting force can be controlled.

When the engaging force of each clutch 61, 75 is made sufficiently large, the differential between the front and rear wheels is locked, and when the engaging force is moderately relaxed, this differential is allowed. When the exciting current of the electromagnet 79 is stopped and the clutch 75 is released, the ball cam 69
Cam thrust force disappears and the clutch 61 is released,
The differential becomes free.

Such control of the differential limiting force by the electromagnet 79 is manually operated from the driver's seat or automatically according to road surface conditions or vehicle steering conditions.

The output shaft 11 is arranged in parallel with the input shaft 3 at the bottom of the transfer case 21, and an output shaft sprocket 81 meshing with the chain transmission mechanism 13 is integrally formed on the outer periphery thereof. The output side sprocket 81 is almost entirely submerged in the oil in the oil sump 83 when stationary. Also,
A hollow 85 having a tapered hole is formed in the axial center of the output shaft 11, and the magnet 8 is provided on the inner circumference of the maximum diameter portion of the hollow 85.
7 are provided.

Both ends of the output shaft 11 are bearings 89a, 8
The transfer case 21 is supported by 9b.
A plurality of notches 91 are provided in the circumferential direction of the inner boss of the transfer case 21b of the bearing 89b supporting portion. The front end of the output shaft 11 is the transfer case 2
1, which is connected to the propeller shaft on the front wheel side. A seal 93 is arranged between the transfer case 21 and the output shaft 11 at the protruding portion of the output shaft 11, and a blind plug 95 is fixed to the output side end of the cavity 85.

A lubricating oil pump 1 is mounted on the differential case 25.
5 are arranged. Oil pump 15 is differential case 2
5 is connected by a key and is rotationally driven by receiving a driving force from the engine. The case 103 of the oil pump 15 is fixed to the transfer case 21 with a screw 105.

A flow path 109 and an oil strainer 111 are connected in this order to the suction port 107 of the oil pump 15. The oil strainer 111 at the suction side tip penetrates the bottom side wall of the transfer case 21 and is arranged in the cavity 85 of the output shaft 11. The bottom wall side wall penetrating portion 113 of the transfer case 21 of the flow path 109 is fixed by welding.

When the transfer device 1 operates, the oil pump 15 is driven and the oil in the oil sump 83 is sucked through the oil strainer 111, the flow path 109, and the suction port 107. Then, the oil discharged from the oil pump 15 passes through the discharge port 115, the flow path 117 provided in the differential case 25, and the flow path 119 provided in the input shaft 3 to the input shaft 3, the center differential 5, the differential limiting device 7, and the rear. Wheel-side output shaft 9
Is supplied to each lubrication part.

As described above, since the cavity 85 is provided in the shaft center portion of the output shaft 11 and the oil strainer 111 is disposed therein, the cavity is generated even if the oil in the oil sump 83 is agitated by the operation of the chain transmission mechanism 13. There is no agitation of the oil in 85, and since the oil is filled in the cavity 85 through the notch 91 of the inner boss of the transfer case 21, it is possible to prevent sucking air from the oil strainer 111. Further, since the oil strainer 111 is arranged apart from the bottom of the transfer case upward and the magnet 87 arranged in the cavity 85 adsorbs the dust in the oil, it is possible to prevent the dust from being sucked in.

Next, a second embodiment will be described with reference to FIG.

This embodiment is a transfer device for a four-wheel drive vehicle. The structure and function of this transfer device 301 are the same as those of the first embodiment except for the front wheel side output shaft part at the bottom of the transfer case.

Therefore, in order to avoid duplication of explanation, the first
Only the differences from the embodiment will be described here. The reference numerals are not attached to the constituent members whose description is omitted.

The output shaft 311 is a transfer case 321.
An output side sprocket 381, which is arranged in parallel with the input shaft 303 at the bottom and meshes with the chain transmission mechanism 313, is integrally formed on the outer periphery thereof. Transfer case 321
The inner bottom portion is an oil reservoir 383 of lubricating oil, and the output side sprocket 381 is almost entirely submerged in the oil in the oil reservoir 383 when stationary. Further, a tapered hole-shaped cavity 385 is formed in the axial center of the output shaft, and a magnet 387 is arranged on the inner circumference of the maximum diameter portion of the cavity 385. In addition, a cylindrical guard cylinder 503 that surrounds the oil strainer 511 is disposed in the cavity 385. The flange portion 505 of the guard cylinder 503 is sandwiched between the bearing 389b and the transfer case 321b.

Bearings 389 are provided at both ends of the output shaft 311.
The transfer case 321 is supported by a and 389b. A plurality of notches 391 are provided in the circumferential direction of the inner boss of the transfer case 321b of the bearing 389b supporting portion. The front end of the output shaft 311 projects from the transfer case 321, and is connected to the propeller shaft on the front wheel side. A seal 393 is arranged between the transfer case 321 and the output shaft 311 at the projecting portion of the output shaft 311, and a blind plug 395 is fixed to the output side end of the cavity 385.

When the transfer device 301 operates, the lubricating oil pump 315 is driven, and the oil sump 383.
Oil is sucked through the oil strainer 511, the pipe line 509, and the suction port 507. Then the oil pump 315
The oil discharged from the discharge port 515, the differential case 3
25 through the flow path 117 and the input shaft 303 through the flow path 519, the input shaft 303, the center differential 305,
The differential limiting device 307 and the rear wheel side output shaft 309 are supplied to each lubricated portion.

As described above, since the cavity 385 is provided in the shaft center portion of the output shaft 311 and the oil strainer 511 is disposed therein, the cavity in the oil reservoir 383 is agitated by the operation of the chain transmission mechanism 313. There is no agitation of the oil in 385 and the oil is transferred to the transfer case 32.
The air is prevented from being sucked from the oil strainer 511 because the cavity 385 is filled through the notch 391 of the first inner boss.

Furthermore, the guard cylinder 503 prevents the oil around the oil strainer 511 from rotating around in the cavity 385 as the output shaft 311 rotates, and prevents the oil from separating from the oil strainer 511 by centrifugal force. It becomes easier for the air to accumulate in the surroundings, eliminating the problems of air intake and oil shortage. Further, since the oil strainer is arranged apart from the bottom of the transfer case upward and the magnet 387 arranged in the cavity 385 adsorbs dust in the oil, the ease of sucking dust is eliminated.

[0042]

In the transfer device of the present invention, since the oil strainer is arranged in the cavity of the output shaft at the bottom of the case, the weight of the output shaft can be reduced, and the exclusive structure for mounting is not necessary. It is possible to prevent generation of abnormal noise due to suction, oil shortage, and seizure of the oil pump due to suction of dust.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment.

FIG. 2 is a sectional view of a second embodiment.

FIG. 3 is a front view of a conventional example.

[Explanation of symbols]

 1,301 Transfer device 3,303 Input shaft 11,311 Output shaft 15,315 Oil pump 21,321 Transfer case 85,385 Cavity 111,511 Oil strainer

Claims (1)

[Claims] 1. A transfer case, an input shaft supported by the transfer case and receiving a driving force from an engine, a transfer case supported by the transfer case, disposed below an oil level of the transfer case, and connected to and driven by the input shaft. An output shaft, an oil pump for lubricating a lubricated portion of the input shaft, and an oil strainer provided on a suction side of the oil pump are arranged in a cavity provided at an axial center of the output shaft. Transfer device.