JP2000142014A - Water-proof structure of wheel bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an invasion of water into a bearing. SOLUTION: An oil-removing aperture 50 of a backing plate 40 is formed on a projecting portion 40A forwardly deviated from the lowermost point 26B of a flange portion 26A in which water drops W are accumulated. As a result, since water drops accumulated in the lowermost point 26B of the flange portion 26A of a housing end 26 rearwardly flows and is dropped by a wind pressure at the time of a vehicle traveling, it can be prevented that the water drops are invaded from the oil-removing aperture 50 into a space 44 even if the inside of the space 44 formed at an inner side portion of a bearing retainer 42 becomes a negative pressure by a rotation of a rear axle shaft 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof structure of a wheel bearing, and more particularly to a waterproof structure of a wheel bearing for preventing water from entering a wheel bearing used for a vehicle such as an automobile.

[0002]

2. Description of the Related Art Conventionally, as an example of a waterproof structure of a wheel bearing of a vehicle such as an automobile, Japanese Utility Model Application Laid-Open No. 61-19680 is disclosed.
The structure disclosed in Japanese Patent Application Publication No. JP-A-2005-11095 is known. Hereinafter, the waterproof structure of the wheel bearing will be described.

[0003] As shown in FIG. 4, in the waterproof structure of the wheel bearing, a hub drum 102 and a backing plate 104 slidably contacting the hub drum 102 from inside a wheel 100.
The water droplets that have entered through the gap 106 between the inner surface and the inner surface of the backing plate 104 flow down along the inner surface of the backing plate 104 as shown by an arrow S in FIG. The protruding ridge 104A at the top of the plate 104 is slightly higher on the spindle 109 side, and the top surface 108A of the spindle flange 108 is also slightly higher on the spindle 109 side, lower on the backing plate 104 side, and inclined on both sides. It is divided and flows down along the side surface 108B of the spindle flange 108. As a result, the water droplet does not flow toward the spindle 109 and does not flow into the wheel bearing 112 through the seal 110.

[0004] In such a waterproof structure of the wheel bearing, as shown in FIG.
0 when the oil seal 122 is broken, and the rear axle shaft 124 and the bearing retainer 126
The water that has entered the inside of the bearing retainer 126 is drained from the gap 128 between the housing end 12 and the housing end 12.
There is known a configuration in which a groove 120B is provided in a flange 120A of a No. 0 and an oil vent hole 132 is formed in a backing plate 130.

[0005]

However, in such a waterproof structure of the wheel bearing, the oil drain hole 132 formed in the backing plate 130 is located at the lowest point of the flange 120A of the housing end 120.
Water droplets W are likely to accumulate at this site. As a result, the rotation of the rear axle shaft 124 causes the housing end 1
When a negative pressure is applied to the inside of the housing 20, as shown by an arrow Y, water flows backward into the bearing retainer 126 from the oil drain hole 132, and the water enters the bearing 134 disposed inside the housing end 120. As a result, the bearing 134 may be damaged.

The present invention has been made in view of the above circumstances, and has as its object to provide a waterproof structure for a wheel bearing that can prevent water from entering the inside of a bearing.

[0007]

According to the present invention, a housing end for covering a wheel bearing for supporting an axle shaft, and a backing plate fixed to a flange portion of the housing end and having an oil vent hole are provided. The waterproof structure of a wheel bearing provided, wherein an oil vent hole of the backing plate is provided at a position deviated from a lowermost point of a flange portion of the housing end.

Accordingly, since the oil drain hole of the backing plate is formed at a position deviated from the lowest point of the flange portion of the housing end, the oil drain hole has
Water drops are hard to adhere. As a result, even if the housing end and the inside of the bearing retainer become negative pressure due to the rotation of the axle shaft, water can be prevented from entering the inside of the bearing from the oil drain hole.

According to a second aspect of the present invention, in the waterproof structure for a wheel bearing according to the first aspect, the oil drain hole of the backing plate is displaced from the lowest point of the flange portion of the housing end toward the front side of the vehicle. Position.

Therefore, in addition to the contents described in the first aspect, due to the wind pressure during traveling of the vehicle, water droplets collected at the lowest point of the housing end flange flow backward and fall. Therefore, even if the housing end and the inside of the bearing retainer become negative pressure due to the rotation of the axle shaft, it is possible to effectively prevent water from entering the inside of the bearing from the oil drain hole.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a waterproof structure for a wheel bearing according to the present invention will be described with reference to FIGS.

In the drawings, an arrow FR indicates a vehicle forward direction, an arrow UP indicates a vehicle upward direction, and an arrow IN indicates a vehicle width inside direction.

As shown in FIG. 3, in this embodiment, a brake drum 16 is fixed to a flange portion 10A of a rear axle shaft 10 by a hub bolt 12 and a hub nut 14. A disc wheel 18 is fixed to the brake drum 16 by a hub bolt 12 and a hub nut 14, and a tire 20 is set on the disc wheel 18.

A housing tube 22 into which the rear axle shaft 10 is inserted is supported by a vehicle body via a bracket 24. A housing end 26 is provided at an end of the housing tube 22.

As shown in FIG. 2, the rear axle shaft 10 is connected to the housing end 2 via a bearing 28.
6 is rotatably supported by the inner peripheral portion. A spacer 30 is interposed between the end 22A of the housing tube 22 and the bearing 28, and an oil seal 32 is provided between an outer peripheral portion of the spacer 30 and an inner peripheral portion of the housing end 26. It is arranged. A through hole 34 is formed in the flange portion 26 </ b> A of the housing end 26 in parallel with the rear axle shaft 10.

As shown in FIG. 1, the housing end 2
The sixth flange portion 26A has a hexagonal shape in a side view (as viewed from the axial direction of the rear axle shaft 10), and a total of four through holes 34 are formed at upper and lower sides of both sides.

As shown in FIG. 2, the housing end 2
The backing plate set bolts 36 are inserted into the through holes 34 formed in the flange portion 26A of the No. 6 from the inside in the vehicle width direction (left side in the drawing), and are screwed to these backing plate set bolts 36. The nut 38 allows the backing plate 40 to be
And is fixed to the flange portion 26A of the housing end 26 through the boss. Note that a brake assembly 43 is fixed to the backing plate 40.

A bearing retainer 42 is fixed to the flange 26A of the housing end 26 with the backing plate 40 interposed therebetween by the backing plate set bolt 36 and the nut 38. As a result, a space 44 is formed inside the bearing retainer 42. The backing plate 40
A paper gasket (not shown) is provided between the bearing and the bearing retainer 42.

As shown in FIG. 1, a lower part of the backing plate 40 is formed with a downwardly convex portion 40A, and a portion of the bearing retainer 42 facing the convex portion 40A is formed downwardly. The projection 42A is formed. Further, the convex portion 40A and the convex portion 42A are formed on the flange portion 26 of the housing end 26 having a hexagonal shape.
A is located forward of the vehicle body from the lowermost point 26B of A.

Therefore, the convex portion 4 of the backing plate 40
0A and the convex portion 42A of the bearing retainer 42, forward of the vehicle body from the lowest point 26B of the flange portion 26A,
A protrusion 44A of the space 44 is formed.

As shown in FIG. 2, an oil drain hole 50 is formed in the convex portion 40A of the backing plate 40, and water, oil, etc. accumulated in the space 44A through the oil drain hole 50 are discharged. It is possible. Also,
Since the convex portion 40A and the oil vent hole 50 of the backing plate 40 are disposed at a position forward of the vehicle body from the lowermost point 26B of the flange portion 26A of the hexagonal housing end 26, the uppermost portion of the flange portion 26A of the housing end 26 is formed. Water or the like accumulated at the lower point 26B is difficult to reach the oil drain hole 50.

Next, the operation of the present embodiment will be described.

The water droplets entering the inside of the disc wheel 18 and reaching the flange 26A of the housing end 26 are
As shown by arrow A in FIG. 1, the lower part 2 of the flange 26A moves downward along the periphery of the flange 26A.
The water accumulates at 6B and becomes a water droplet W. On the other hand, in the present embodiment, the oil release hole 50 of the backing plate 40 is provided.
However, it is formed on the convex portion 40A which is deviated from the lowest point 26B of the flange portion 26A where the water droplet W accumulates. For this reason, it is difficult for the water droplet W to accumulate in the portion of the oil drain hole 50.

As a result, in this embodiment, the rotation of the rear axle shaft 10 causes the bearing retainer 4 to rotate.
Even if the inside of the space 44 formed in the inner part of 2 becomes negative pressure,
Water droplets hardly enter the space 44 from the oil drain hole 50, so that water can be prevented from entering the bearing 28.

Further, in the present embodiment, the oil drain hole 50 of the backing plate 40 is provided with the convex portion 4 which is displaced from the lowermost point 26B of the flange portion 26A where the water droplet W accumulates toward the vehicle front side.
0A. As a result, due to the wind pressure during traveling of the vehicle, water droplets accumulated at the lowest point 26B of the flange portion 26A of the housing end 26 flow toward the rear of the vehicle (in the direction of arrow B in FIG. 1) and fall. Even if the pressure in the space 44 formed inside the bearing retainer 42 becomes negative,
Water droplets can be effectively prevented from entering the space 44 from zero.

In the above, the present invention has been described in detail with respect to a specific embodiment. However, the present invention is not limited to such an embodiment, and various other embodiments are within the scope of the present invention. It is clear to a person skilled in the art that is possible. For example, in the present embodiment, the backing plate 4
No oil drain hole 50 is formed in flange portion 2 where water droplet W accumulates.
6A is formed at a position deviated from the lowermost point 26B to the front side of the vehicle, but instead of this, the oil drain hole 50 of the backing plate 40 is formed in the flange portion 26A in which the water droplet W is accumulated.
May be formed at a position deviated rearward from the lowermost point 26B of the vehicle. Further, in the present embodiment, the waterproof structure of the wheel bearing of the present invention is applied to the rear wheel of the vehicle. However, the waterproof structure of the wheel bearing of the present invention is applicable to other wheels such as the front wheel of the vehicle.

[0027]

According to the first aspect of the present invention, there is provided a wheel bearing having a housing end for covering a wheel bearing for supporting an axle shaft, and a backing plate fixed to a flange portion of the housing end and having an oil vent hole. In the waterproof structure, since the oil release hole of the backing plate is provided at a position deviated from the lowest point of the flange portion of the housing end, there is an excellent effect that water can be prevented from entering the inside of the bearing.

According to a second aspect of the present invention, in the waterproof structure of the wheel bearing according to the first aspect, the oil drain hole of the backing plate is displaced from the lowest point of the flange portion of the housing end toward the front of the vehicle. Since it is located at the position, there is an excellent effect that water can effectively be prevented from entering the inside of the bearing from the oil drain hole.

[0029]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view taken along line 1-1 of FIG.

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

FIG. 3 is a sectional view along the axial direction of a rear axle shaft showing a rear wheel to which a waterproof structure for a wheel bearing according to an embodiment of the present invention is applied.

FIG. 4 is a cross-sectional view showing a waterproof structure of a wheel bearing according to a conventional embodiment.

FIG. 5 is a sectional view taken along the axial direction of a rear axle shaft showing a waterproof structure of a wheel bearing according to another conventional embodiment.

[Explanation of symbols]

 Reference Signs List 10 rear axle shaft 16 brake drum 18 disc wheel 26 housing end 26A flange end of housing end 26B lowest point of flange portion 28 bearing 36 backing plate set bolt 38 nut 40 backing plate 40A convex portion of backing plate 42 bearing retainer 42A bearing retainer Convex part 50 Through hole

Claims (2)

[Claims] 1. A waterproof structure for a wheel bearing, comprising: a housing end that covers a wheel bearing that supports an axle shaft; and a backing plate that is fixed to a flange portion of the housing end and that has an oil vent hole. A waterproof structure for a wheel bearing, wherein an oil vent hole of the backing plate is provided at a position deviated from a lowermost point of an end flange portion. 2. The waterproof structure for a wheel bearing according to claim 1, wherein the oil release hole of the backing plate is located at a position deviated from the lowermost point of the flange portion of the housing end toward the front of the vehicle.