JPH1148805A - Differential device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lengthen the life, of a differential device by suppressing damage of raceway track parts of components of respective taper roller bearing. SOLUTION: In a differential device A having oil circulation structure, at least, upper half areas of confronting end faces of two taper roller bearings 5, 6 for supporting a pinion gear shaft 4 are provided with barriers 15, 15 for limiting oil inflow into the two bearing 5, 6. In this event, since the oil inflow from the upper halves of the two taper roller bearings 5, 6 is limited, the total quantity of oil passing through the respective taper roller bearings 5, 6 becomes small and consequently the infiltration of gear abrasion powder can be reduced. However, because oil can flow in from lower halves of the taper roller bearings 5, 6, the respective taper roller bearings 5, 6 are lubricated by oil passing therethrough moderately.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential device used for a driving system of various automobiles.

[0002]

2. Description of the Related Art As a conventional differential device, for example, there is one disclosed in Japanese Utility Model Laid-Open No. 2-58156.

[0003] The differential device of this publication has a general structure, that is, is provided with a pinion gear shaft that is rotationally driven by a drive shaft, and a differential transmission mechanism that is rotationally driven by this pinion gear. The pinion gear shaft is rotatably supported at two locations separated in the axial direction from the differential case via tapered roller bearings.

[0004] As a lubricating form of the two tapered roller bearings described above, oil stored in a differential case is made to spring upward with the rotation of the ring gear, and this oil is supplied to an intermediate portion of the two tapered roller bearings. And flow into the bearing. The oil that has passed through the inside of the tapered roller bearing is returned to the ring gear side. As described above, the oil is circulated inside the differential case to lubricate the tapered roller bearing.

[0005]

By the way, generally,
During operation, a phenomenon occurs in which the oil in the differential case is biased toward the space where the tapered roller bearing is disposed due to the oil jumping action of the ring gear. Since the deviation of the oil becomes more remarkable as the rotation speed increases, the two tapered roller bearings may be completely immersed in the oil in an extreme case.

As described above, when the tapered roller bearing is completely immersed in the oil, the amount of oil passing through each tapered roller bearing becomes excessive, and the raceway surfaces of the inner and outer rings and the outer peripheral surface of the tapered roller are reduced. It is easy to be damaged. This is because gear wear powder is usually contained in oil, so if the amount of oil passing increases as described above, the amount of gear wear powder passing through each tapered roller bearing can be said to be enormous. As a result, the above-mentioned internal damage is likely to occur.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a differential device that suppresses damage to raceway portions of the components of each tapered roller bearing and improves the life.

[0008]

According to a first differential device of the present invention, the oil in a differential case is flipped upward with the rotation of a ring gear driven by a pinion gear, and the oil in the differential case is lifted with respect to the differential case. The double tapered roller bearing has an oil circulation structure in which two axially separated pinion gear shafts are guided to an intermediate region between two tapered roller bearings rotatably supporting the pinion gear shaft and then returned to the ring gear side. In at least the upper half region of the opposed end surfaces of the two bearings, there is provided a barrier that restricts oil from flowing into the bearings. In this case, since the oil inflow from the upper half of the two tapered roller bearings is restricted, the total amount of oil passing through each tapered roller bearing is reduced, and as a result, the intrusion of gear wear powder can be reduced. However, since the oil can flow in from the lower half of the tapered roller bearing, each tapered roller bearing is lubricated by a moderately passing oil.

[0009] The second differential device of the present invention comprises:
In the first device, the barrier is a shield plate mounted on an inner peripheral surface of a bearing mounting wall in a differential case. In this case, since the existing differential case can be used, unnecessary cost increase can be avoided.

[0010] A third differential device of the present invention comprises:
In the second device, the shield plate is formed in a horseshoe shape by cutting a lower half of an annular plate. In this case, the shield plate can be easily manufactured by, for example, punching, which is advantageous in cost.

[0011] A fourth differential device of the present invention comprises:
In the second device, the shield plate is an annular plate having a through hole for a pinion gear shaft at the center and a through hole for an oil passage in a lower half region. In this case, not only the same action as in the third device is obtained, but also the entire circumference of the shield plate can be mounted on the bearing mounting wall by press-fitting or the like, so that the fixing strength of the shield plate is increased and the shield plate is improved. Deformation is avoided.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the embodiments shown in FIGS.

1 to 3 relate to an embodiment of the present invention. FIG. 1 is a longitudinal sectional side view of a differential device used in an automobile, and FIG. 2 is a sectional view taken along line (2)-(2) of FIG. FIG. 3 is a perspective view of the shield plate of FIG.

In the figure, A indicates the entire differential device, 1 is a differential case, 2 is a differential transmission mechanism, 3 is a pinion gear, and 4 is a pinion gear shaft.

The differential case 1 includes a case body 1a made of a sheet metal press and a bearing case 1b made of a casting connected to a front portion of the case body 1a. In the stopped state, it is stored at a level as indicated by L in FIGS.
The above-mentioned bearing case 1b is provided with two bearing mounting annular walls 1 on which the following two tapered roller bearings 5 and 6 are mounted.
3, 14 and an oil introduction path 11 for guiding oil flowing during operation to an intermediate portion between the annular walls 13 and 14, and oil guided from the oil introduction path 11 is returned to the case body 1a. And an oil recirculation path 12 are provided.

The differential transmission mechanism 2 differentially interlocks left and right axles (not shown), and is disposed on the case body 1a side of the differential case 1.

The pinion gear 3 meshes with the ring gear 2 a of the differential transmission mechanism 2 and is formed integrally with the inner end of the pinion gear shaft 4.

The pinion gear shaft 4 is rotatably supported at required positions of a bearing case 1b of the differential case 1 via tapered roller bearings 5 and 6, respectively, at two locations separated in the axial direction. A flange joint 7 to which a drive shaft (not shown) is connected is provided at an outer end of the pinion gear shaft 4. That is, in the differential device A, the pinion gear shaft 4 serves as a drive shaft, and drives the above-described differential transmission mechanism 2.

The above-mentioned two tapered roller bearings 5, 6
Are defined in relative positions by a cylindrical spacer 8 interposed therebetween. An oil seal 9 for preventing oil leakage to the outside is provided between the outer peripheral surface on the outer end side of the pinion gear shaft 4 and the inner peripheral surface on the small end side of the bearing case portion 1b of the differential case 1. A seal protection cup 1 for covering the oil seal 9 from the outside is mounted on the outer end side of the pinion gear shaft 4.
0 is attached. The front (right side in FIG. 1) tapered roller bearing 5 is incorporated from the small end side opening of the bearing case portion 1b, and the rear (left side in FIG. 1) tapered roller bearing 6 is mounted.
Is installed from the opening on the large end side of the bearing case 1b.

Next, the characteristic configuration of the present invention will be described. That is, the oil guided to the oil introduction path 11 is prevented from flowing into the inside of each tapered roller bearing 5, 6 from the upper half thereof into the bearing case portion 1 b of the differential case 1, while each of the tapered roller bearings 5, 5 is prevented. A barrier is provided to allow the lower half to flow into the interior of 6. In this embodiment, shield plates 15 and 15 that are separate from the bearing case portion 1b are used as the barrier. Specifically, as shown in FIGS. 2 and 3,
An annular plate provided with an insertion hole for the pinion gear shaft 4 at the center is formed in a horseshoe shape in which a lower half of the annular plate is cut out. As shown in FIG. 1, these shield plates 15, 15 are provided on the inner peripheral surfaces of the annular walls 13, 14 for mounting the bearing of the bearing case portion 1 b, at the end edges on their facing sides, by tapered roller bearings. They are press-fitted in such a manner as to cover the upper halves of the end faces on the sides facing each other.

Next, the above-described differential device A
The flow of oil at the time of operation will be briefly described.

Here, the ring gear 2a of the differential transmission mechanism 2
In the normal rotation driving state, for example, as shown by the arrow in FIG. 1, the rotation of the ring gear 2a causes the oil in the differential case 1 to jump upward. Become like

The oil which has been splashed up above the differential case 1 is guided downward from an oil introduction passage 11 provided at an upper portion of the bearing case portion 1b, so that a pair of two tapered roller bearings is formed. It flows between 5 and 6.

Here, the above oil is supplied to the shield plate 1
Since the inflow into the tapered roller bearings 5 and 6 is prevented by 5 and 15, the flow is diverted right and left by the cylindrical spacer 8 externally fitted to the pinion gear shaft 4 and dropped downward. Part of the oil that has fallen down is
Annular wall 1 for mounting bearings by notch in lower half of 5, 15
The oil flows from the oil passage 16 formed between the tapered roller bearings 5 and 6 to the inside of the tapered roller bearings 5 and 6 which are not concealed by the shield plates 15 and 15 to lubricate the tapered roller bearings 5 and 6. Will do. On the other hand, most of the oil that has fallen downwards is supplied to the oil return path 1 of the bearing case 1b.
2 returns to the case body 1a side.

As described above, during the operation of the differential device A, the oil in the differential case 1 is circulated in the above-described flow path, and the components inside the differential device are lubricated. . However, as described above, each tapered roller bearing 5, 6
As a result, it is possible to suppress damage to the tapered roller bearings 5 and 6 due to gear abrasion powder contained in the oil. 6 can contribute to improvement in durability.
In addition, although the flow of oil into each of the tapered roller bearings 5, 6 is restricted, the lower half of each of the tapered roller bearings 5, 6 permits the flow of oil, so that the lubricating action is sufficient. .

It should be noted that the present invention is not limited to only the above embodiment, and various applications and modifications are conceivable.

(1) FIG. 4 shows another example of the shield plate 15. The shield plate 15 here is a circular plate having a circular shaft insertion hole 17 at the center, and an appropriate number of through holes 18 of an appropriate size are provided in the lower half thereof. In this case, the entire circumference of the shield plate 15 is the annular wall 13 for mounting the bearing,
14, the through holes 18 of the shield plate 15 form the oil passages 16 in the above embodiment.

(2) FIG. 5 shows still another example of the shield plate 15. The shield plate 15 here is a circular plate having an oval shaft insertion hole 17 at the center. In this case, the hole portion of the shaft insertion hole 17 of the shield plate 15 excluding the insertion area of the pinion gear shaft 4 becomes the oil passage 16 in the above embodiment.

(3) The above shield plates 15 can be incorporated into the openings formed in the inner walls of the bearing mounting annular walls 13 and 14 in a loosely fitted state. It is also possible to support the shield plate with the outer rings of the bearings 5 and 6 to prevent the shield plate from coming off.

(4) In each of the above embodiments, a separate shield plate 15 is used as a barrier for the bearing case portion 1b. However, the inner portions of the annular walls 13 and 14 for mounting the bearings are integrally formed by hanging down. Also included in the present invention.

[0031]

According to the first to fourth aspects of the present invention, even if a large amount of oil in the case is supplied to the intermediate portion of the double tapered roller bearing by the jumping of the high-speed rotating ring gear,
The barrier is designed to limit the oil inflow to each tapered roller bearing, so that the total amount of oil passing through each tapered roller bearing can be reduced, and as a result, the intrusion of gear wear powder can be reduced. Become. Therefore, damage to the raceway of the components of the tapered roller bearing can be suppressed as much as possible, and it is possible to contribute to the improvement of the bearing life.

In particular, according to the second aspect of the present invention, as the barrier,
Since a shield plate separate from the differential case is used, it is possible to avoid an unnecessary increase in cost, for example, by using an existing differential case. In addition, since such a shield plate can be mounted by press-fitting on the bearing mounting wall of the differential case, the accuracy of the shape of the shield plate can be made relatively low, and the assembling thereof becomes easy. In addition, the pressure resistance can be set high by increasing the thickness.

Further, according to the third and fourth aspects of the present invention, the shield plate can be easily manufactured by, for example, punching, which is advantageous in terms of cost. In addition, according to the fourth aspect of the present invention, in addition to the above effects, the entire periphery of the shield plate can be mounted on the bearing mounting wall by press-fitting or the like. Can be avoided.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a differential device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line (2)-(2) of FIG.

FIG. 3 is a perspective view of the shield plate of FIG. 1;

FIG. 4 is a perspective view showing another example of the shield plate of FIG. 3;

FIG. 5 is a front view showing still another example of the shield plate of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Differential case 1a Case main body 1b Bearing case part 2 Differential transmission mechanism 2a Ring gear 3 Pinion gear 4 Pinion gear shaft 5, 6 Tapered roller bearing 11 Oil introduction path of bearing case part 12 Oil return path of bearing case part 13, 14 Bearing case part Annular wall for mounting bearings on the vehicle 15 Shield plate 16 Oil passage

Claims (4)

[Claims] 1. The oil in a differential case is
Along with the rotation of the ring gear that is driven to rotate by the pinion gear, the ring gear jumps upward and moves away from the differential case in the axial direction of the pinion gear shaft.
A differential device having an oil circulation structure adapted to return to the ring gear side after being guided to an intermediate region between the two tapered roller bearings rotatably supporting the two locations, wherein at least one of opposed end faces of the double tapered roller bearing is provided. A differential device, wherein an upper half region is provided with a barrier that restricts oil flow into the bearings. 2. The differential device according to claim 1, wherein the barrier is a shield plate mounted on an inner peripheral surface of a bearing mounting wall in a differential case. 3. The differential device according to claim 2, wherein the shield plate is formed in a horseshoe shape by cutting out a lower half of an annular plate. 4. The differential device according to claim 2, wherein the shield plate has an annular hole provided with a through hole for a pinion gear shaft at the center and a through hole for an oil passage in a lower half region. A differential device, characterized in that: