JP2879188B2 - Lubrication system for rear front axle differential in rear two axle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rear-front axle differential lubrication device for a rear two-axle vehicle, and more particularly to a suction device for an oil pump provided for lubricating a rear-front axle differential.

[0002]

2. Description of the Related Art A differential carrier case of a rear front shaft is connected to a rear portion of a transfer case provided with a lubricating oil pump near a front end, and a bottom portion of the transfer case and a bottom portion of the differential carrier case are communicated with each other. After the oil collected at the bottom of the axle is supplied by pressure to the lubricating parts by an oil pump, a strainer is provided in a carrier case or a transfer case in the two-axle wheel. However, even in the case of providing in any case,
Since it is necessary to select a stable part of the oil surface that is not easily affected by the agitation by the ring gear and install a strainer to ensure lubrication performance, a strainer is conventionally provided at a stable oil level in the differential carrier case. Alternatively, a strainer is provided at a stable oil level in the transfer case.

However, when the strainer is provided in the differential carrier case as in the former case, there is a problem that the distance from the oil pump provided at the front end of the transfer case to the strainer becomes too large. Also, when a strainer is provided inside the transfer case as in the latter case, the oil in the differential carrier case, whose oil level is low due to the scraping lubrication effect of the ring gear, is less likely to be sucked in. Oil may be circulated only in the inside, and the temperature of the oil may easily rise.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a stable lubrication function even on steep uphill slopes without being affected by ring gear agitation. An object of the present invention is to provide a lubricating device for a rear-front axle differential in a two-axle vehicle.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a case in which an enclosure is provided at a lower portion of the front end of a differential carrier case of a front shaft after being connected to a rear portion of a transfer case provided with a lubricating oil pump near the front end. A communication hole is provided for holding the bottom of the transfer case in communication with the inside of the enclosure. The strainer disposed inside the enclosure is connected to a suction port of an oil pump provided near a front end of the transfer case via a suction pipe.

[0006]

In the lubricating apparatus configured as described above, during normal traveling, oil flows from the transfer case to the inside of the enclosure and to the differential carrier case, so that the inside of the enclosure is always filled with oil. Further, the inside of the enclosure is not affected by the stirring action of the ring gear, and a fixed amount of oil can be circulated.

On the other hand, when the vehicle is going up a steep slope or down a steep slope, the oil may be biased to one of the transfer case and the differential carrier case.
However, since the oil is secured around the strainer by the volume of the enclosure, the amount of oil sucked into the oil pump can be stabilized.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a cross-sectional view of a rear front axle for a rear two-axle equipped with a lubricating device according to the present invention, FIG. 2 is a cross-sectional view showing an enlarged part of an enclosure of FIG. 1, and FIG. It is the front view which looked at the case from the front of the vehicle.

In these figures, a differential carrier case 3 of a rear front shaft is connected to a rear portion of a transfer case 2 provided with a lubricating oil pump 1 near a front end. And
A ring gear 8 of a rear front shaft differential 7 is driven by a drive pinion 6 interlocked with a drive shaft 4 connected to a propeller shaft (not shown) via an interaxle differential 5. The transfer case 2
The partition 9 separating the differential carrier case 3 and the differential carrier case 3 is provided with a through hole 10 for communicating the bottoms of the two cases 2 and 3 with each other.

An enclosure 11 is provided below the front end of the differential carrier case 3 and a communication hole 1 for communicating the bottom of the transfer case 2 with the interior of the enclosure 11.
2 are provided. Then, a strainer 13 disposed inside the enclosure 11 is connected to a suction port of the oil pump 1 via a suction pipe 14.

Accordingly, when the oil pump 1 is driven with the rotation of the drive shaft 4, the oil inside the enclosure 10 is sucked into the oil pump 1 via the strainer 13 and the suction pipe 14, and the oil pump 1
Transfer case 2 and differential carrier case 3
It is supplied to each lubricating part inside. Note that, inside the differential carrier case 3, the oil is also scooped up and lubricated with the rotation of the ring gear 8.

Reference numeral 15 denotes an insertion hole for the strainer 13 provided in the partition wall 10, 16 is a tightening bolt for the transfer case 2 and the differential carrier case 3, and 17 is a pump drive gear fixed to the input shaft of the oil pump 1. Drive gear 1
By engaging the drive shaft 4 with the drive shaft 4, the oil pump 1 is driven when the drive shaft 4 rotates. Also, the through shaft 18
A rear rear shaft differential is connected to a rear end of the rear shaft via a propeller shaft (not shown), and the interaxle differential 5 is locked when the sleeve 19 is engaged.

In the lubricating apparatus constructed as described above, the scraping action by the small-diameter drive pinion 6 is performed in the transfer case 2, but the scraping lubrication by the large-diameter ring gear 8 in the differential carrier case 3. Since the operation is performed, the oil level in the differential case 3 is lower than the oil level in the transfer case 2. Accordingly, during normal traveling, the oil in the transfer case 2 flows through the communication holes 12 and the through holes 10 to the inside of the enclosure 11 and the differential carrier case 3, so that the interior of the enclosure 11 is always filled with oil. The interior of the enclosure 11 is not affected by the stirring action of the ring gear 8, so that the oil level is stable.

For this reason, when the oil pump 1 is driven with the rotation of the drive shaft 4, the oil inside the enclosure 10 is sucked into the oil pump 1 via the strainer 13 and the suction pipe 14. The oil discharged from the oil pump 1 is supplied to the lubricating parts in the transfer case 2 and the differential carrier case 3 via an oil gallery 21 provided in the drive shaft 4 through a discharge passage 20 under pressure.

The oil thus supplied to the lubricating parts flows down to the bottom of each of the cases 2 and 3 together with the oil supplied to the lubricating parts from the bottom of the differential carrier case 3 after lubricating and cooling the lubricating parts. I do. Then, the oil flows into the inside of the enclosure 11 and the inside of the differential carrier case 3 from the bottom of the transfer case 2 and is sucked by the oil pump 1. The oil that has flowed down to the differential carrier case 3 is again supplied to the lubricating parts by the scraping action of the ring gear 8, and the same circulation follows.

Further, in such oil circulation,
The interior of the enclosure 11 provided with the strainer 13 is filled with oil as described above, and the oil inside the enclosure 11 is not affected by the action of the ring gear 8 to lift and stir. For this reason, since the oil having a stable oil level which is not affected by the stirring action of the ring gear 8 is held inside the enclosure 11, the oil is supplied to the lubricating parts by the oil pump 1 under pressure. The amount of oil can be stabilized.

On the other hand, when the vehicle is going up a steep slope or down a steep slope, the oil may be biased to one of the transfer case 2 and the differential carrier case 3. However, around the strainer 13 is an enclosure 11
Since the oil is secured only for the volume of the oil, the amount of oil sucked into the oil pump 1 is stabilized, and the lubrication performance is maintained.

[0018]

As is apparent from the above description, according to the lubricating apparatus according to the present invention, the oil temperature rises or the suction pipe becomes longer not only during normal running but also during steep ascent. Lubricating oil can be stably supplied to the lubricating portions in the transfer case and the differential carrier case of the rear two-axle without the need.

[Brief description of the drawings]

FIG. 1 is a sectional view of a rear front axle for a rear two-axle equipped with a lubrication device according to the present invention.

FIG. 2 is a cross-sectional view showing an enlarged part of an enclosure in FIG. 1;

FIG. 3 is a front view of the differential carrier case of FIG. 1 as viewed from the front of the vehicle.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 oil pump 2 transfer case 3 differential carrier case 4 drive shaft 5 interaxle differential 6 drive pinion 7 rear and front shaft differential 8 ring gear 9 partition 10 through hole 11 enclosure 12 communication hole 13 strainer 14 suction pipe 15 strainer insertion hole 16 tightening Bolt 17 pump drive gear 18 through shaft 19 sleeve 20 discharge passage 21 oil gallery

Claims (1)

(57) [Claims] A differential carrier case of a rear front shaft is connected to a rear portion of a transfer case provided with a lubricating oil pump near a front end, and a bottom portion of the transfer case and a bottom portion of the differential carrier case are communicated with each other, so that both ends are connected. In a two-axle vehicle in which oil at the bottom of the case is supplied to lubricated parts by an oil pump, a communication hole is provided at the lower front end of the differential carrier case, and the bottom of the transfer case is communicated and held inside the enclosure. And a differential lubricating device for a rear front axle in a rear two-axle vehicle, wherein a strainer disposed inside the enclosure and a suction port of the oil pump are connected via a suction pipe.