JPS645124Y2 - - Google Patents

Description

[Detailed description of the invention] "Industrial application field" This invention relates to a structure that prevents the shaft from falling out of the differential case, and in particular, a structure that prevents damage to the shaft seal member during assembly and disassembly. Regarding the retaining structure.

"Prior Art" Conventionally, for example, as shown in FIG. 5, a drive shaft for an automobile has a distal end mounted in a differential case 20.
One that is fitted into the inner diameter portion 22 of the differential side gear spline is known. The tip end 12 of the drive shaft 10 has an annular groove 14 formed in an annular shape in the circumferential direction of the shaft to prevent the shaft from coming off.
A clip 16 is fitted into the holder. This clip 16 must be received within the annular groove 14 when the shaft tip 12 is inserted into the splined bore 22. For this reason, clip 16
The annular groove 14 is formed relatively deep so that it does not get in the way when it is contracted and stored. After the shaft tip 12 passes through this spline inner diameter section 22, this clip 16 expands to prevent the drive shaft 10 from coming off.
The differential side gear 20 partially protrudes from the annular groove 14.
It engages with the spline end face of a to prevent the drive shaft 10 from coming off.

"Problems to be Solved by the Invention" As described above, in the conventional drive shaft 10, the annular groove 14 into which the clip 16 is fitted is formed relatively deep, so that the clip 16 is loosely fitted into the annular groove 14. It will be done. for example,
As shown in FIG.
The lip part 24 of the rubber oil seal 24 is attached to a.
When a is brought into contact with the clip 16 and pressed, one side 16a of the clip 16 is pushed deep into the annular groove 14. The other side 16b of the clip 16 is pushed out of the annular groove 14 accordingly. Therefore, the annular groove 14
The open end portion 15 of is exposed to the lip portion 24a. For example, as shown in FIG. 5, the shaft insertion port 22 of the differential case 20
Oil seal 24 attached to the periphery of a
When the drive shaft 10 is inserted, the lip portion 24a is damaged by the open end 15 of the annular groove 14 exposed by the clip 16 shifting due to contact with the shaft tip 12, and this may be a cause of oil leakage. A problem had arisen.

``Purpose of the invention'' Therefore, the main purpose of this invention is to be able to smoothly insert the shaft into the shaft insertion port without damaging the sealing member attached to the shaft insertion port of the differential case. It is an object of the present invention to provide a shaft retaining structure capable of preventing oil leakage and the like.

"Means for solving the problem" In order to achieve the above purpose, the main means adopted by this invention is to
An annular elastic member whose outer diameter is smaller than the shaft diameter when contracted is fitted, and when the shaft is inserted into a differential case with an oil seal attached to the shaft insertion port, the annular elastic member reduces the shaft diameter. In the shaft retaining structure which prevents the shaft from coming off from the differential case by increasing the diameter, a chamfer is formed at the opening end of the annular groove.

"Operation" When inserting the shaft from the shaft insertion port of the differential case, the inclined surface of the chamfered part of the annular groove causes the oil seal that engages with this annular groove to slide, and the oil seal at the open end of the annular groove slides. Avoid sharp hits.

``Effect of the invention'' According to this invention, even if the opening end of the annular groove hits the shaft insertion port of the differential case, the opening of the annular groove is chamfered, so that part becomes slippery. Sharp hits at the open end are avoided. Therefore, the shaft can be smoothly inserted into the shaft insertion port.

Furthermore, the lip of the oil seal installed at the shaft insertion port of the differential case is able to slip through the annular groove of the shaft, leaving it undamaged and preventing oil leakage. be able to.

The above objects, other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments with reference to the drawings.

``Example'' Figure 1 is a side view including a cross section of the main part showing the structure of an embodiment of this invention, Figure 2 is an enlarged sectional view of the main part in Figure 1, and Figure 3 is a clip shown in Figure 2. FIG. 4 is an explanatory diagram showing a preferred embodiment structure of this invention.

The drive shaft 10 is inserted into the differential case 20 (FIG. 5), and its tip 1
2 is the differential side gear spline inner diameter portion 22 (fifth
(Fig.). A spline 12a is formed on the outer peripheral surface of the shaft tip 12 for spline fitting with the spline inner diameter portion 22.

As shown in FIG. 2, the shaft tip 12 is formed with an annular groove 14 having an appropriate depth in the radial direction near the tip surface 12b. The annular groove 14 is formed in a ring shape, extending in the circumferential direction of the shaft tip 12 and perpendicular to the spline 12a. On the entire circumference of the open end 15' of this annular groove 14, there are side walls 14a facing each other.
and 14b, chamfered portions 18a and 18b are formed, respectively.

These chamfered portions 18a and 18b are each formed at a predetermined depth from the open end 15' of the annular groove 14.

A clip 16 having a suitable elasticity is fitted into the annular groove 14 thus formed.
The clip 16 has a circular shape when viewed in cross section, and is, for example, a ring-shaped member with a portion of its circumference cut out, as shown in FIG. Note that, like the conventional clip, the clip 16 is loosely fitted into the annular groove 14 so as to be movable in the radial direction of the shaft. It is formed in a size that protrudes from 14. Further, the depth of the annular groove 14 is set to such an extent that the clip 16 can fit into the annular groove 14 when the clip 16 is pressed in the radial direction and reduced in size.

For example, assume that the shaft tip 12 described in FIG. 2 is inserted into the shaft insertion port 22a of the differential case 20 shown in FIG. 5. At this time, the oil seal 24 is inserted into the annular groove 14.
When the lip portion 24a abuts against the clip (FIG. 2), the lip portion 24a pushes one side 16a of the clip 16 deep into the annular groove 14. The other side 1 of the clip 16
6b is accordingly pushed out of this annular groove 14. Therefore, one side 16 of the clip 16
The open end 15' of the annular groove 14 where a is located is exposed to the lip portion 24a. but,
Chamfered portions 18a and 18 are provided at the open end 15'.
b is formed, so that the abutting lip portion 24
A sharp hit against a is avoided. as a result,
The lip portion 24a passes through the open end portion 15' without being damaged, and the shaft tip portion 12 is smoothly inserted into the differential case 20.
Therefore, oil will not leak from the differential case 20.

FIG. 4 is an explanatory diagram showing a more preferred embodiment of this invention. This figure shows the shaft tip 12.
However, as mentioned above, differential case 20
This schematically shows a state in which the differential side gear spline is inserted into the inner diameter portion 22 of the differential side gear spline. In this case, the spline 12a formed on the shaft tip 12 and the spline 22a formed on the inner peripheral surface of the spline inner diameter portion 22 mesh with each other. Chamfered portions 23 and 25 are formed at both ends of the spline 22a in the axial direction, that is, at the entrance and exit sides of the shaft tip 12, respectively, at chamfer angles α and β.

With such a configuration, the spline inner diameter portion 2
When the shaft tip 12 is fitted into the shaft tip 12, that is, when the shaft tip 12 moves in the direction of the arrow A, the chamfer 23 is formed by, for example, one chamfer 18 of the annular groove 14 set at a chamfer angle α'.
Opposite a. Next, when the shaft tip 12 is extracted from the inside of the spline inner diameter section 22, that is, when the shaft tip 12 moves in the direction of arrow B, the chamfer 25 is cut into the annular groove 14a set at the chamfer angle β', for example. Other chamfered part 1
Opposite 8b.

On the other hand, the clip 16 is inserted when the shaft tip 12 is inserted into the spline inner diameter portion 22 (arrow A
direction), once the annular groove 14 is formed on the inclined surface of the chamfered portion 23.
Pushed inside. Conversely, when pulled out from the spline inner diameter portion 22 (in the direction of arrow B), the chamfered portion 2
It is pressed into the annular groove 14 again by the inclined surface 5.
In particular, the clip 16 shown in FIG. 4 shows the latter case. That is, when removing the shaft tip 12 from the spline inner diameter portion 22, the clip 16 moves in the direction of arrow A against the pressure of the chamfered portion 25.
Trying to "escape" in the direction. To prevent this, the chamfer angle β' of the chamfered portion 18b is set to satisfy the relationship β>β'. Similarly, when inserting the shaft tip 12 into the spline inner diameter section 22, the clip 16 tends to "escape" in the direction of arrow B against the pressure of the chamfered portion 23. To prevent this, the chamfered portion 18a
The chamfer angle α' is set to satisfy the relationship α>α'.

In this way, in this preferred embodiment, in addition to the effects of the embodiments described above, by providing the annular groove with a chamfered portion at a predetermined angle, the shaft is prevented from coming off when the shaft is inserted or extracted. It is possible to sufficiently prevent the clip used from coming off.

[Brief explanation of the drawing]

Fig. 1 is a side view including a cross section of the main part showing the structure of an embodiment of this invention, Fig. 2 is an enlarged sectional view of the main part in Fig. 1, and Fig. 3 is a plan view of the clip shown in Fig. 2. FIG. 4 is an explanatory diagram showing a preferred embodiment structure of this invention, and FIGS. 5 and 6 are side views including a cross section of the main parts showing a conventional shaft stopper structure which is the background of this invention. . Explanation of symbols, 10... Drive shaft, 12
...shaft tip, 14... annular groove, 14a,
14b...Side wall, 16...Clip, 18a, 1
8b...Slope surface.

Claims (1)

[Claims for Utility Model Registration] 1. An annular elastic member whose outer diameter is smaller than the shaft diameter when contracted is fitted into an annular groove formed at the end of the shaft, and the shaft is fitted with an oil seal in the shaft insertion port. When the shaft is inserted into the differential case, the annular elastic member becomes larger in diameter than the shaft diameter, thereby preventing the shaft from coming off from the differential case. A shaft retaining structure, characterized in that a chamfer is formed at the opening end of the annular groove. 2. The shaft slip-off prevention structure according to claim 1, wherein the chamfer angle of the annular groove opening end is smaller than the chamfer angle formed on the end face of the shaft insertion port of the differential case.