JPS63158358A - Bearing lubricating structure for drive pinion - Google Patents

Abstract

PURPOSE:To make a sufficiency amount of lubricating oil feedable without entailing any oil leakage from a joined part, by installing a cylindrical bush member in an oil feed passage of the joined part of each casing. CONSTITUTION:A bush fitting hole 21 is installed in an opening of an oil feed passage 8 at the side of a pinion casing 3, one side of a cylindrical bush member 20 is fitted in this hole ad positioned, then an O-ring 22 is fitly installed in a ring groove on an outer circumferential surface of the bush member fitted in an opening hole of the oil feed passage 8 at the side of a casing body 6. With this constitution, even if the number of sheets of a shim 10 is varied, an oil leakage from a joined part of the oil feed passage 8 is in no case caused there, so that a sufficient amount of lubricating oil is feedable to a taper roller bearing 5b.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a bearing lubrication structure for a drive pinion that inputs power rotation to a ring gear of a differential mechanism.

(Prior art) Conventionally, in a differential unit (final gear unit) that separates the power rotation transmitted from the propeller shaft to the left and right wheels, the differential has a ring gear (hypoid gear) as shown in Fig. 4. 〉 1 is engaged with the drive pinion gear 2 from the orthogonal direction to input power rotation, and since the drive pinion gear 2 receives a large thrust in the axial direction,
A drive pinion shaft 4 is rotatably mounted on a pinion casing (gear carrier) 3 with the support of a pair of tapered roller bearings 5a and 5b.

Furthermore, in the conventional differential unit, the casing structure is such that the pinion casing 3 as a gear carrier supporting the drive pinion gear 2 is separated from the casing body 6 in which the differential mechanism is incorporated, and the drive pinion gear is connected to the ring gear 1. This makes it easy to assemble and adjust the position.

Furthermore, the tapered roller bearings 5a and 5b incorporated in the pinion casing 3 are lubricated using lubricating oil scattered by the rotation of the ring gear 1 integrated with the differential case.

However, in such conventional bearing lubrication,
There is no problem with the lubrication of the tapered roller bearing 5a located on the drive pinion gear 2 side because it directly receives the scattering of lubricating oil due to the rotation of the ring gear 1. However, the taper roller bearing 5a located on the outside of the drive pinion shaft 4 to which the propeller shaft is connected is The roller bearing 5b is only supplied with the lubricating oil that has passed through the tapered roller bearing 5a, and there is a risk of insufficient lubrication because the lubricating oil cannot be sufficiently supplied.

Therefore, the inventors installed an oil gutter 7 inside the casing body 6 to collect the lubricating oil scattered by the rotation of the ring gear 1 inside the casing body 6, and the lubricating oil collected by the oil gutter 7 is transferred to the oil supply passage. 8 has proposed a lubrication structure in which lubrication is supplied to the outer tapered roller bearing 5b.

Since the oil supply passage 8 that supplies the lubricating oil collected in the casing body 6 to the tapered roller bearing 5b passes through the joint between the casing body 6 and the pinion casing 3, oil leakage from this joint is prevented. In order to do this, an O-ring 9 is interposed.

(Problem to be solved by the invention) However, the oil supply passage 8 passing through the casing joint part
When O-ring 9 was installed to prevent oil leakage from the engine, the following problem occurred.

That is, in the two-part casing structure, when the drive pinion gear 2 of the pinion casing 3 is engaged with the ring gear 1 of the casing main body 6, a gear is inserted between the casing coupling surfaces in order to adjust the engagement position of the two. Alternatively, a plurality of shims 10 are interposed, and the distance (1) between the coupling surface 6a of the casing body 6 and the coupling surface 3a of the pinion casing 3 is as shown in FIG. As a result, the crimping interval of the O-ring 9 also changes, and if the number of shims 10 increases, the O-ring 9
There was a problem in that the sealing function of the oil supply path 8 was lost due to this.

(Means for solving the problems) The present invention was made in view of the above problems, and
A drive pinion that reliably prevents oil leakage from the oil supply passage passing through the casing joint 81 without being affected by the meshing position adjustment between the ring gear and the drive pinion gear due to the intervention of a shim on the casing joint surface. The purpose is to provide a bearing lubrication structure.

In order to achieve this object, the present invention provides a cylindrical bushing member that is fitted from both sides into the opening hole of the oil supply passage passing through the casing joint portion having a two-part structure.

(Function) According to the configuration of the present invention, since the oil supply passage passing through the casing joint portion is connected by the cylindrical bushing member, the number of shims used to adjust the meshing position of the gears changes. However, there is no oil leakage from the joint part of the oil supply path, and there is no loss of the advantages of the two-part casing structure. Can supply lubricating oil.

(Embodiment) FIG. 1 is a sectional view showing one embodiment of the present invention, and shows a differential unit as a cross section viewed in a horizontal state.

First, to explain the structure, 6 is a casing body of a differential unit, and inside the casing body 6, a ring gear 1 is provided which is fixed to a differential case 13. Inside the differential case 13, a pair of pinion made gears 14a are provided.
, 14b are rotatably attached to the differential case 13 by a pinion made shaft 15, and a side gear 16a is located at a position orthogonal to the pinion made gears a, 14b.

16b is engaged, side gear '16a, 16b
is the axle shaft 17a taken out on both sides.

It is fixed to the tip of 17b by spline fitting or the like. The differential case 13 is rotatably supported within the casing body 6 by tapered roller bearings 18a and 18b on both sides thereof.

On the other hand, a drive pinion gear 2 is engaged with a ring gear 1 incorporated in a differential case 6 from a direction perpendicular to the ring gear 1, and a drive pinion shaft 4 formed integrally with the drive pinion gear 2 is connected to a ring gear 1 incorporated in a differential case 6.
It is rotatably supported inside by a pair of tapered roller bearings 5a and 5b.

Drive pinion shaft 4 within pinion casing 3
Tapered roller bearing 5b located on the outside supporting
As a bearing lubrication structure for this, an oil gutter 7 is installed behind the ring gear 1 inside the casing body
is installed so that lubricating oil scattered inside the casing body 6 due to the rotation of the ring gear 1 can be collected by the oil gutter 7. Furthermore, in order to efficiently collect the lubricating oil by the oil gutter 7, a fin 19 is provided behind the ring gear 1 from inside the casing body 6 near the oil gutter 7, and collects the lubricating oil scattered by the rotation of the ring gear 1. The oil comes into contact with the fins 19 to efficiently drain the oil into the gutter 7.

The outflow lower a of the oil gutter 7 is fitted into an oil supply passage 8 which passes from the inside of the casing main body 6 through the inside of the pinion casing 3 and opens at a portion where a tapered roller bearing 5b that supports the outside of the drive pinion shaft 4 is installed. Since this oil supply path 8 passes through the joint between the casing body 6 and the pinion casing 3, in the present invention, a cylindrical bushing member 20 is fitted and fixed in the casing joint in the oil supply path 8. ing.

Further, a desired number of shims 10 are interposed between the connecting surface of the pinion casing 3 and the casing body 6 in order to adjust the meshing position of the ring gear 1 and the drive pinion gear 2.

FIG. 2 is a cross-sectional view showing the casing connection part of the oil supply passage 8 in the embodiment shown in FIG.
A bushing fitting hole 21 is provided in the opening of the bushing member 20, and one of the cylindrical bushing members 20 is fitted and positioned. An O-ring 22 is fitted into the ring groove on the surface.

FIG. 3 shows an exploded view of the pinion casing 3 with the drive pinion gear 2 relative to the casing body 6.

As is clear from FIG. 3, the differential 7 differential unit can be assembled independently into the casing main body 6 side and the pinion casing 3 side, and when the assembly of both is completed, as shown in the figure. Insert the cylindrical bushing member 20 into the opening of the oil supply passage 8 on the side of the pinion casing 3 by i+X, and further incorporate the drive pinion gear 2 as shown in 2a'. 3b with the required number of shims 10 interposed for meshing adjustment.
Assemble the pinion casing 3 thereto and fix it by tightening bolts or the like. At this time, the tip of the bushing member 20 attached to the opening of the oil supply passage 8 on the side of the pinion casing 3 is fitted into the opening of the oil supply passage 8 on the side of the casing main body 6, as shown in FIG. A connected state is created at the casing joint of the oil supply path 8.

By connecting the oil supply path 8 in such a casing divided portion via the cylindrical bushing member 2o, the number of shims 10 used for adjusting the meshing position between the ring gear 1 and the drive pinion gear 2 can be reduced. Even if the connection interval between the casing body 6 and the pinion casing 3 changes, since the connection is made at the casing division part of the oil supply path 8 by the bushing member 20, the casing interval will fluctuate depending on the number of shims 10 used. The oil supply path 8 can be connected without being influenced by the above, and without causing oil leakage at the casing divided portion.

Therefore, the differential unit can be assembled using the number of shims 10 necessary for adjusting the engagement between the ring gear 1 and the drive pinion gear 2 without considering oil leakage at the casing connecting portion of the oil supply path.

In the above embodiment, after the bushing fitting hole 21 is formed at the opening of the oil supply path 8 on the pinion casing 3 side and the bushing member 20 is press-fitted, the oil supply on the casing body 6 side is closed. Although the casing is fitted into the opening of the channel 8 at the same time as the casing is assembled, the casing main body 6
A bushing fitting hole 21 may be formed at the opening of the oil supply passage 8 on the side, and the bushing member 20 may be press-fitted thereinto, and then the pinion casing 3 side may be fitted.

(Effects of the Invention) As explained above, according to the present invention, the casing body is separated into a casing body that incorporates a differential gear mechanism and a pinion casing that incorporates a drive pinion gear.
In a differential unit having a split casing structure, the lubricating oil structure is such that lubricating oil is supplied to the tapered roller bearing that supports the outside of the drive pinion shaft of the drive pinion gear by the oil supply path 8 passing through the casing joint part. Since a cylindrical bushing member is provided that fits from both sides of the opening hole of the oil supply path passing through the joint, the oil supply will be maintained even if the number of shims for gear mesh adjustment interposed in the casing joint changes. The drive of the drive pinion gear does not cause oil leakage from the connecting part of the drive pinion gear, and the advantage of the two-part casing structure is that the casing body side and the pinion casing side are assembled separately and then assembled. Sufficient lubricating oil can be supplied to the tapered roller bearing provided on the outside of the pinion shaft without causing oil leakage from the casing connection part.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing an embodiment of the present invention, Fig. 2 is a cross-sectional view showing the casing joint part of the oil supply passage in Fig. 1, and Fig. 3 is an exploded view of Fig. 1. , FIG. 4 is a sectional view of a conventional unit equipped with a bearing lubrication structure already proposed by the inventors of the present application, and FIG. 5 is an explanatory diagram showing oil leakage due to the use of an O-ring. 1: Ring gear 2 Nidrive pinion gear 3: Pinion casing 4 Nidrive pinion shaft 5a, 5b, 18a, 18b: Taper roller bearing 6: Casing body 7: Oil gutter 8: Oil supply passage 9: 0 ring 10: Shim 13 : Differential case 14a, 14b: Pinion made gear 15: Pinion made shaft 16a, 16b: Saitoki 7 17a, 17b: Axle shaft 19: Fin 20: Push member 21: Push fitting hole 22: O ring

Claims (1)

[Claims] A casing body with a built-in differential mechanism consisting of a differential case, a ring gear, a pair of pinion maids, and a side gear, and a shaft portion of a drive pinion gear that inputs power rotation to the ring gear are connected by a pair of tapered roller bearings. 2 with a rotatably supported pinion casing
The casing has a split casing structure, and an oil supply passage is formed through a joint portion between the casing body and the pinion casing to supply lubricating oil collected within the casing body to the roller bearing located outside within the pinion casing. A bearing lubrication structure for a drive pinion, characterized in that a cylindrical bushing member is provided which is fitted from both sides of the opening hole of the oil supply passage passing through the joint portion of each of the casings. .