JPH08210473A - Differential gear device for vehicle and washer thereof - Google Patents

Abstract

PURPOSE: To improve lubricatability and to prevent the abrasion of a washer by forming an oil lubricating groove, extended from a peripheral side toward an internal peripheral side to open both end parts, in at least one of contact surfaces with a housing and with a washer arranged between the housing and an end face of a sun gear. CONSTITUTION: A differential gear device A is provided with a housing 1, pair of sun gears 2A, 2B, for instance, three pairs of plant gears 3A, 3B, center washer 4A and an end washer 4B. Each pair of the planet gears 3A, 3B is meshed with the sun gears 2A, 2B. Here inside the center washer 4A formed with a through hole 41 in a central part, three oil introducing holes 43 are formed. Each oil introducing hole 43 is provided so as to be positioned in an intermediate part of adjacent two engaging protrusions 42, 42, to enlarge this width gradually in accordance with toward the outside from inside the washer 4A. In this way, lubricating oil in a differential gear case can be sufficiently supplied to a washer internal peripheral side through the oil introducing groove 43.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a parallel shaft type differential gear device for a vehicle and a washer used for the same.

[0002]

2. Description of the Related Art Generally, in a parallel shaft type differential gear for a vehicle, a washer is arranged between the end faces of a pair of sun gears and between the end faces of the sun gear and a housing. The washer is adapted to rotate integrally with the housing. Therefore, when the sun gear rotates relative to the housing as in the differential operation, the sun gear rotates while contacting the sun gear. Then, due to the frictional resistance generated between the washer and the sun gear during this relative rotation, the ratio of torques transmitted from the engine to the pair of output shafts via the differential gear device (torque bias ratio).
Is set to a predetermined size.

By the way, since the washer rotates while being in contact with the sun gear, it tends to wear early. In order to prevent such early wear, JP-A-5-272600
In the one disclosed in the publication, a through hole is formed in the facing portion of the washer facing the tooth groove of the sun gear, and the lubricating oil is forcibly fed into this through hole by the feeding action of the torsion tooth of the sun gear. Hold it. Then, the lubricating oil held in the through hole is supplied between the contact surfaces of the washer and the sun gear.

[0004]

However, in the washer described in the above publication, the portion of the washer facing the tooth groove is located on the outer peripheral side. Therefore, the through hole has to be formed on the outer peripheral side. If the through hole is formed on the outer peripheral side of the washer, a sufficient amount of lubricating oil cannot be supplied to the inner peripheral side of the contact surface between the washer and the sun gear. For this reason, there is a problem that it is not possible to sufficiently prevent early wear on the inner peripheral side of the washer. Further, when the through holes are formed, the contact area with the sun gear is reduced by that amount, the surface pressure is increased, and the wear is likely to occur.

If the through hole is an elongated hole extending toward the inner peripheral side of the washer, the problem of supplying lubricating oil to the inner peripheral side of the washer can be solved, but such an elongated hole is formed. Then, there is a problem that the contact area between the washer and the sun gear is further reduced and the washer wears earlier.

[0006]

In order to solve the above-mentioned problems, the invention according to claim 1 provides a housing which is driven to rotate, and is rotatably provided in the housing such that an axis of the housing coincides with an axis of the housing. And a pair of sun gears that are rotatably provided in the housing with the axis parallel to the axis of the housing, and mesh with the pair of sun gears, respectively, and at least a pair of planet gears that mesh with each other, the housing, and the housing. In a vehicle differential gear device, which is disposed between the end surface of the sun gear and a washer that rotates integrally with the housing, in at least one of the contact surfaces of the housing and the washer, from the outer peripheral side to the inner peripheral side. It is characterized in that an oil introduction groove is formed which extends toward and is open at both ends. In this case, it is desirable to make the cross-sectional area of the groove larger on the outer peripheral side than on the inner peripheral side for the reason described later. Further, it is desirable that the groove be inclined so as to be directed toward the front side in the rotation direction of the housing when the vehicle is moving forward from the inner peripheral side toward the outer peripheral side. Further, the invention according to claim 4 is a housing that is rotationally driven, and a pair of sun gears that are rotatably provided in the housing such that the axis of the housing coincides with the axis of the housing.
The pair of vehicle differential gear devices, which are rotatably provided in the housing with the axis parallel to the axis of the housing, respectively mesh with the pair of sun gears, and at least a pair of planetary gears meshing with each other. In the washer arranged between the end faces of the sun gear or between the housing and the end face of the sun gear, an oil introduction hole penetrating from the outer peripheral surface to the inner peripheral surface is formed. In this case, it is desirable to make the cross-sectional area of the oil introduction hole larger on the outer peripheral side than on the inner peripheral side for the reason described later. Further, it is desirable that the oil introduction hole be inclined with respect to a radial line passing through the center of the washer. Further, the washer is composed of a pair of half bodies that are butted in the axial direction, and at least one butting surface of the pair of half bodies is provided with an oil introduction recess extending from the outer peripheral surface to the inner circumferential surface. It is desirable to form the oil introduction hole by the oil introduction recess and the abutting surface of the other half.

[0007]

In the invention according to claim 1, the lubricating oil stored in the differential case reaches the inner peripheral side of the washer through the oil introduction groove and enters the inner peripheral portion between the washer and the housing. Therefore, a sufficient amount of lubricating oil can be supplied to the inner peripheral portion. In this case, by increasing the cross-sectional area of the oil introduction groove on the outer peripheral side, it is possible to increase the amount of lubricating oil that enters the oil introduction groove. Further, when the oil introduction groove is inclined as described above, the lubricating oil can be forcibly fed to the inner peripheral side of the oil introduction groove by the feeding action of the oil introduction groove accompanying the rotation of the housing when the vehicle moves forward. . Further, in the invention according to claim 4, the lubricating oil stored in the differential case reaches the inner peripheral side through the oil introduction hole and enters between the washer and the sun gear or the housing.
Therefore, a sufficient amount of lubricating oil can be supplied between them. In this case, by increasing the cross-sectional area of the oil introduction hole on the outer peripheral side, it is possible to increase the amount of lubricating oil that enters the oil introduction hole. When the oil introducing hole is inclined, the washer is installed in the differential gear device in a state where the oil introducing hole is inclined similarly to the oil introducing groove according to the third aspect, whereby the lubricating oil is introduced into the oil introducing hole. Can be forcibly sent to the inner circumference side. Further, if the washer is composed of a pair of halves, and the oil introduction hole is formed by the oil introduction recess formed in at least one half and the other half, the oil introduction hole is easily formed. be able to.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be described with reference to. 1 to 3 show an embodiment of a differential gear device provided with a washer according to claim 4, FIG. 1 is a sectional view taken along line XX of FIG. 2, and FIG. 2 is taken along line YY of FIG. FIG. The differential gear device A shown in these figures includes a housing 1, a pair of sun gears 2A and 2B, at least a pair (three pairs in this embodiment) of planetary gears 3A and 3B, a center washer (washer) 4A, and an end washer ( It has a washer) 4B.

The housing 1 has a bottom 11a at one end and a cylindrical main body 11 having the other end open, and the main body 11
The cover 12 is fixed to the other end of the main body 11 by a screw T and shields the other end opening of the main body 11. Rotational torque of an engine (not shown) is transmitted to the housing 1 via a ring gear (not shown), and the housing 1 is rotationally driven about its axis L.

Through holes 11b penetrating through the bottom portion 11a of the main body 11 are formed at equal intervals in three circumferential directions, and through holes 1 passing through the peripheral wall portion of the main body 11 are formed.
1 c are arranged and formed at equal intervals in six circumferential directions.
Further, a through hole 12 a penetrating this is also formed in the lid body 12 so as to face the through hole 11 b of the main body 11. Then, the lubricating oil stored in the differential case (not shown) is introduced into the housing 1 through the through holes 11b, 11c, 12a.

The bottom 11a of the main body 11 and the lid 1
2, support holes 11d and 12b extending on the axis L are formed respectively. An axle (not shown) is rotatably inserted in each of the support holes 11d and 12b.
At the ends of the housing 1 of each axle, the sun gears 2A, 2A, 2
Each B is spline-coupled. An axle spacer 5 for positioning each axle is arranged between the pair of sun gears 2A, 2B.

In the housing 1, three pairs of planetary gears 3 are provided.
A and 3B are rotatably arranged so as to be located between the three oil introducing holes 11b. Each planetary gear 3
A and 3B mesh with one of the sun gears 2A and 2B, and mesh with each other. As a result, during differential operation, one sun gear 2A (2B) rotates at a lower speed than the housing 1, and the other sun gear 2B (2A) rotates at a higher speed than the housing 1 by that amount.

A center washer 4A is arranged between the end faces of the sun gears 2A and 2B. As shown in FIG. 3, the center washer 4A has a disc shape, and a through hole 41 is formed in the center thereof. The inner diameter of the through hole 41 is formed to be slightly larger than the outer diameter of the axle spacer 5. As a result, between the inner periphery of the center washer 4A and the outer periphery of the axle spacer 5,
An annular space S is formed. Further, on the outer peripheral surface of the center washer 4A, three engaging projections 42 are formed at equal intervals in the circumferential direction. As shown in FIG. 2, each engagement protrusion 42 is fitted between the pair of planetary gears 3A and 3B, so that the center washer 4A rotates integrally with the housing 1. Therefore, the center washer 4A has the sun gear 2A,
It will be in sliding contact with each end face of 2B.

As shown in FIG. 3, three oil introduction holes 43 are formed inside the center washer 4A. Each oil introduction hole 43 is arranged so as to be located at an intermediate portion between two adjacent engaging projections 42, 42, and an inner end portion thereof opens to an inner peripheral surface of the through hole 41 and an outer end portion thereof. The part is open to the outer peripheral surface. Further, although the oil introduction hole 43 is formed to have a rectangular cross section in this embodiment, the shape thereof is arbitrary.

The width of the oil introducing hole 43, that is, the width of the center washer 4A in the circumferential direction gradually increases from the inside to the outside. As a result, the oil introduction hole 4
The cross-sectional area of 3 gradually increases from the inside to the outside.

Further, the oil introducing hole 43 is formed in a spiral shape so that the outer portion is located forward of the inner portion in the rotation direction of the housing 1 (the direction of arrow F in FIG. 2) when the vehicle is moving forward. Has become. As a result, the oil introduction hole 4
3 is inclined with respect to a radial line passing through the center of the center washer 4A so as to be directed in the arrow F direction from the inner peripheral side toward the outer peripheral side. Moreover, the inclination angle of each part of the oil-introduced oil 43 gradually increases from the inside to the outside. The oil introduction hole 43 can be formed by, for example, electric discharge machining or lost wax casting.

As shown in FIG. 1, the bottom portion 1 of the body 11 is
An accommodating recess 11e is formed in the center of 1a, and an accommodating recess 12c is formed in the center of the lid 12.
The end washer 4 is provided in each of the accommodation recesses 11e and 12c.
B is housed in each. One end washer 4
B has one end surface in contact with the bottom portion 11a and the other end surface in contact with the sun gear 2A, and the end washer 4B and the bottom portion 11a.
The frictional resistance between the end washer 4B and the sun gear 2 is
It is larger than the frictional resistance with A. Therefore, the end washer 4B rotates integrally with the housing 1 and comes into sliding contact with the sun gear 2A during differential operation.

As described above, the end washer 4B
Since it is designed to rotate integrally with the housing 1 due to frictional resistance, it is not necessary to form the engaging projection 41 in the center washer 4A. The center washer 4A is formed in the same manner as the center washer 4A except for this point and the outer diameter being slightly smaller than the center washer 4A. Further, the inner diameter of the through hole 41 of the end washer 4B is slightly larger than the outer diameter of the output shaft (= the inner diameter of the support holes 11d and 12b), and the inner circumference of the end washer 4B and the outer circumference of the output shaft are different from each other. An annular space S ′ similar to the annular space S is also formed therebetween. The other end washer 4B
Is similar to the one end washer 4B except that it is in contact with the lid 12 and the sun gear 2B.

In the differential gear device A having the above structure, a part of the lubricating oil introduced into the housing 1 enters from the outer peripheral side between the center washer 4A and the end faces of the sun gears 2A and 2B. This point is similar to the conventional differential gear device.

A part of the lubricating oil introduced into the housing 1 flows into the annular space S through the oil introduction hole 43. In this case, since the cross-sectional area of the oil introduction hole 43 is large on the outer peripheral side, a large amount of lubricating oil can be flowed in as compared with the case where the oil introduction hole 43 is formed to have a constant cross-sectional area.
Moreover, since the oil introduction hole 43 is inclined toward the arrow F direction from the inner peripheral side toward the outer peripheral side,
A larger amount of lubricating oil can flow into the annular space S when the vehicle, which is frequently used, moves forward. Furthermore, since the inclination angle of the oil introduction hole 43 is large on the outer peripheral side, the amount of lubricating oil flowing into the annular space S can be further increased. Then, the lubricating oil that has flowed into the annular space S enters from the inner peripheral side between the center washer 4A and the sun gears 2A and 2B.

As described above, in the differential gear device A, the lubricating oil not only enters from the outer peripheral side but also from the inner peripheral side between the center washer 4A and the sun gears 2A and 2B. Therefore, a sufficient amount of lubricating oil can be supplied between the center washer 4A and the sun gears 2A, 2B. Therefore, it is possible to prevent early wear of the center washer 4A. Moreover, since the oil introduction hole 43 is formed inside the center washer 4A, the contact area between the center washer 4A and the sun gears 2A, 2B does not change. Therefore, early wear of the center washer 4A can be prevented more reliably. In addition, such a point is the same between the end washer 4B and the sun gears 2A and 2B.

Next, another embodiment of the washer according to claim 4 will be described. The washer 6 shown in FIG. 4 is generally the same as the center washer 4A except that a pair of half bodies 6A and 6B are fixed to each other. That is, the washer 6 has a circular shape, and the through hole 6 corresponding to the through hole 41 of the center washer 4A is formed in the center thereof.
1 is formed, and an engagement protrusion 62 corresponding to the engagement protrusion 42 is formed on the outer peripheral surface.

The respective halves 6A and 6B are shown in FIG.
As shown in (B) and (C), the center washer 4A is used.
Has a shape bisected at the central portion in the axial direction, and the abutting surfaces 64A and 64B are fixed by diffusion bonding, adhesion or the like. The oil introduction recesses 63A, 63 are formed on the abutting surfaces 64A, 64B of the respective half bodies 6A, 6B.
Three Bs are formed. Each oil introduction recess 63A, 6
3B has a shape in which the oil introduction hole 43 of the center washer 4A is divided into two parts, and the half body 6 is aligned with each other.
When A and 6B are butted and fixed, an oil introduction hole 63 corresponding to the oil introduction hole 43 is formed.

Since the washer 6 has the same shape as the center washer 4A as a whole, the same effect as that of the center washer 4A can be obtained. Moreover, the hole introduction recesses 63A and 63B forming the oil introduction hole 63 can be cut by, for example, an end mill. Therefore, the oil introduction hole 63 can be easily formed.

Next, the differential gear device according to claim 1 will be described. In the differential gear device B shown in FIG.
The end washer 7B is formed in a simple disc shape,
Oil introduction hole is not formed. Then, on the bottom surface of the housing recess 12c of the housing 1 that houses the end washer 7B instead of the oil introduction hole, as shown in FIG. 6, the end on the outer peripheral side is opened to the through hole 12a, and the end on the inner peripheral side is opened. Part is support hole 1
An oil introduction groove 12d opened to 2b is formed. Similarly, an oil introduction groove 11f is also formed on the bottom surface of the accommodation recess 11e. Each of the oil introducing grooves 11f and 12d is formed in a spiral shape like the oil introducing oil 43. Since the configuration other than the above-described configuration is similar to that of the differential gear device A, the description thereof will be omitted.

In the differential gear device B, the lubricating oil flows into the annular space S'through the oil introducing grooves 11f and 12d, and the inner peripheral side is provided between the end washer 7B and the sun gears 2A and 2B. Get in from. Therefore, it is possible to prevent early wear of the end washer 7B. Further, although the oil introducing grooves 11f and 12d are formed in the housing 1,
The housing 1 and the end washer 7B rotate integrally without rotating relative to each other. Therefore, those grooves 11
Even if f and 12d are formed, the contact area between the end washer 7B and the sun gears 2A and 2B does not decrease. As is clear from this, the oil introduction grooves 11f and 12d
Instead of this, an oil introduction groove may be formed on the contact surface of the end washer 7B with the housing 1.

The present invention is not limited to the above embodiment, but the design can be changed appropriately. For example, in the above-described differential gear device A, the inclination angle of the oil introduction hole 43 is increased on the outer peripheral side, but it may be inclined at a constant inclination angle, or it may pass through the center of the washer 4A (4B). It may be formed on the radial line without being inclined with respect to the radial line. Further, although the cross-sectional area of the oil introduction hole 43 is increased on the outer peripheral side, the cross-sectional area of each part may be constant. Further, in the above-described differential gear device B, the end portion on the outer peripheral side of the oil introduction groove 12d is directly opened to the through hole 12a, but as shown in FIG. 7, both ends penetrate the end surface of the lid body 12. A communication groove 12e communicating with the holes 12a, 12a may be formed, and the end portion on the outer peripheral side of the oil introduction hole 12d may be opened to the communication groove 12e. This also applies to the oil introduction groove 11e.

[0028]

As described above, according to claim 1 or 4,
According to the invention related to (1), it is possible to obtain the effect that it is possible to prevent early wear of the washer. In addition, claim 2,
According to the third, fifth or sixth aspect of the invention, it is possible to obtain the effect that the early wear of the washer can be prevented more reliably. Further, according to the invention of claim 7, it is possible to obtain the effect that the oil introduction hole of the washer can be easily formed.

[Brief description of drawings]

1 shows an embodiment of the invention according to claim 4,
FIG. 3 is a sectional view taken along line XX of FIG. 2.

FIG. 2 is a sectional view taken along line YY of FIG. 1 showing the same embodiment.

3A and 3B show an embodiment of a center washer used in the embodiment, FIG. 3A is a plan view thereof, FIG. 3B is a sectional view taken along line BB of FIG. (C) is a plan view seen from below.

FIG. 4 shows another embodiment of the center washer used in the embodiment, FIG. 4 (A) is a plan view thereof, and FIG.
(B) and (C) are the P arrow view and Q arrow view of FIG. 4 (A), respectively.

FIG. 5 shows an embodiment of the invention according to claim 1,
It is a sectional view similar to FIG.

FIG. 6 is a view taken along the line ZZ in FIG.

FIG. 7 is a view similar to FIG. 6, showing another embodiment of the invention according to claim 1.

[Explanation of symbols]

 A differential gear device B differential gear device 1 housing 2A sun gear 2B sun gear 3A planetary gear 3B planetary gear 4A center washer (washer) 4B end washer (washer) 11f oil introduction groove 12d oil introduction groove 43 oil introduction hole 63 oil Introduction hole 63A Oil introduction recess 63B Oil introduction recess

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akinori Misaki, Toyota Town, Toyota City, Aichi Prefecture, 1st Toyota Motor Co., Ltd. (72) Inventor, Kiyonari Ishikawa, 1 Toyota Town, Toyota City, Aichi Toyota Motor Co., Ltd. Within

Claims (7)

[Claims] 1. A housing that is driven to rotate, a pair of sun gears that are rotatably provided in the housing such that the axis of the housing coincides with the axis of the housing, and the axis of the housing is parallel to the axis of the housing. It is rotatably provided and meshes with the pair of sun gears, respectively,
A vehicle differential gear including at least a pair of planetary gears that mesh with each other, and a washer that is disposed between the housing and the end surface of the sun gear with one end surface in contact with the housing and that rotates integrally with the housing. In the device, a differential gear for a vehicle, characterized in that at least one of contact surfaces of the housing and the washer is formed with an oil introduction groove extending from an outer peripheral side toward an inner peripheral side and having both ends open. apparatus. 2. The differential gear device for a vehicle according to claim 1, wherein a cross-sectional area of the oil introduction groove is larger on the outer peripheral side than on the inner peripheral side. 3. The oil introducing groove according to claim 1, wherein the oil introducing groove is inclined toward the front side in the rotation direction of the housing when the vehicle is moving forward from the inner peripheral side toward the outer peripheral side. The vehicle differential gear device described. 4. A housing which is rotationally driven, a pair of sun gears which are rotatably provided in the housing such that the axis of the housing coincides with the axis of the housing, and the axis of the housing is parallel to the axis of the housing. It is rotatably provided and meshes with the pair of sun gears, respectively,
In a washer arranged between the end faces of the pair of sun gears of the vehicle differential gear device including at least a pair of planetary gears meshing with each other, or between the housing and the end faces of the sun gears, an outer peripheral surface is formed inside. A washer for a vehicular differential gear device, characterized in that an oil introduction hole is formed so as to penetrate from to the inner peripheral surface. 5. The washer for a differential gear device for a vehicle according to claim 4, wherein the cross-sectional area of the oil introduction hole is larger on the outer peripheral side than on the inner peripheral side. 6. The oil introduction hole is inclined with respect to a radial line passing through the center of the washer.
Alternatively, the washer of the vehicle differential gear device according to Item 5. 7. The washer comprises a pair of halves axially butted against each other, and at least one butting surface of the pair of halves has an oil introduction recess extending from an outer peripheral surface to an inner peripheral surface, The washer for a vehicle differential gear according to any one of claims 4 to 6, wherein the oil introducing hole is formed by the oil introducing concave portion and the abutting surface of the other half body.