JPH0743490Y2 - Ball bearing self-aligning seal structure - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a self-aligning seal structure for ball bearings.

[Conventional technology]

In a front engine Float-drive vehicle with the engine placed sideways, as shown in FIG. 3, since the differential device 20 is mounted so as to be biased with respect to the center of the vehicle, the differential device 20 and the left and right wheels 21a, 21b are If the distances between the driving shafts are different and the driving shafts having unequal lengths are connected to each other, the moment force applied to the driving shafts becomes different, which impairs the straightness of the vehicle. For this reason,
Currently, the differential device 20 and the drive shaft on the far side
An intermediate shaft 23 is provided between the drive shafts 22a and 22b so that the left and right drive shafts 22a and 22b have the same length.

The intermediate shaft 23 is an output shaft 20 of the differential device 20.
It is supported between a and the bearing A attached to the fixed member 24 of the engine 25 or the like, but it is difficult to accurately match the axes of the intermediate shaft and the output shaft for connection in the actual assembling work. The intermediate shaft 23 is often mounted tilted between the output shaft 20a and the drive shaft 22b.

Therefore, as the bearing A that supports the intermediate shaft 23, a ball bearing that has a function of absorbing the inclination that can smoothly support the intermediate shaft 23 that has an axis inclined and swings and rotates is used.

In this type of ball bearing, the ball rolling surfaces of the inner and outer rings have a radius of curvature that is considerably larger than the ball radius, and the bearing clearance is large, so even if the inner ring tilts with respect to the outer ring, the rotation axis The intermediate shaft can be smoothly supported.

[Problems to be solved by the device]

By the way, since the bearing that supports the intermediate shaft is arranged near the wheels on the bottom surface of the vehicle body, it is susceptible to muddy water, rainwater, dust, etc., and therefore, for preventing the muddy water from entering the inside. A seal structure is required.

4 and 5 show a conventional example in which the ball bearing is provided with a special seal structure for preventing intrusion of muddy water or the like.

In the example shown in FIG. 4, bearing seals 5'for enclosing lubricating grease inside are mounted on both sides of the ball rolling surface 4, and a metal shield plate 6 for preventing intrusion of muddy water or the like is provided outside the bearing seals 5 '. Is attached.

The bearing seal 5'is formed by integrally forming an elastic material 5'b such as rubber on the surface of a metal cored bar 5'a by baking or the like, the outer peripheral end of which is press-fitted into the outer ring 2 and the inner peripheral end thereof. Is a lip portion 13 that is in sliding contact with the outer diameter surface of the inner ring 1. Further, the shield plate 6 has an inner peripheral end press-fitted and fixed to the inner ring 1, and an outer peripheral end thereof enters grooves 14 at both ends of the outer ring 2, and a labyrinth gap 10 is formed between the inner peripheral end and the groove 14.

On the other hand, the example of FIG. 5 has the same basic structure as that of FIG. 4, but differs in that a rubber seal material 15 is attached to the outer peripheral end of the shield plate 12, and this rubber seal material 15 is used for the inner diameter of the outer ring 2. Sliding contact with the surface prevents the entry of muddy water and dust.

In FIGS. 4 and 5, 3 is a ball as a rolling element, and 16 is a cage for holding the ball 3.

However, in the ball bearing as described above, when the inner ring and the outer ring are relatively inclined at the inclination angle α, the distance between the shield plate attached to the inner ring and the bearing seal attached to the outer ring is different in the axial direction and the radial direction of the bearing. It makes a difference.

In this case, in the structure of FIG. 4, since the gap 10 between the one shield plate 6 and the outer ring 2 is larger than the gap that produces the labyrinth effect, muddy water flows from the gap 10 to the inside of the shield plate 6, Dust, etc. will enter. However, it is difficult to completely seal water with the lip portion 13 of the bearing seal 5 ', and muddy water, dust, etc., which have entered the shield plate 6,
There is a problem that the ball enters the inside of the ball rolling surface 4 as it rotates.

On the other hand, in the structure of FIG. 5, when the tightening amount between the rubber seal material 15 and the outer ring 2 is set to be small, if the inner ring and the outer ring are greatly tilted, one rubber seal material 15 and the outer ring 2 are tilted as in the case of FIG. There is a problem that there is a gap between the and where muddy water and dust enter.

However, if the length of the rubber seal material 15 is increased so that the clearance between the rubber seal material 15 and the outer ring 2 is not generated even if the bearing is tilted, the tightening margin of the rubber seal material 15 with respect to the outer ring is increased. There is a problem that the frictional force between 15 and the outer ring 2 increases, causing an increase in rotational torque and an increase in heat generation.

Therefore, the present invention aims to provide a seal structure capable of preventing the intrusion of muddy water, rainwater, dust or the like into the inside regardless of the inclination of the bearing ring by modifying the shape of the bearing seal and the shield plate. There is.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, the present invention has an outer ring 2 having outer diameter ends on both sides of a ball rolling surface 4 of an inner ring 1 and an outer ring 2.
The bearing seal 5 fixed to the inner ring 1 and the shield plate 6 having the inner diameter end fixed to the inner ring 1 are sequentially provided from the inner side, and the outer peripheral surface of the bearing seal 5 is formed with the protruding piece 7 continuously protruding outward on the circumference. Then, the central portion of the side surface of the shield plate 6 is bent to form an annular recess 8 into which the projection piece 7 is inserted, and a labyrinth gap 11 is formed between the annular recess 8 and the projection piece 7, and The side surface 7a on the outer ring side is an inclined surface that approaches the outer ring 2 toward the tip, and the inner and outer side surfaces 8a and 8b of the annular recess 8 facing the protruding piece 7 are inclined so as to separate from each other toward the inside of the bearing. As the surface, the amount of protrusion of the protrusion 7 into the annular recess 8 is set to be larger than the amount of displacement when the inner ring 1 and the outer ring 2 are tilted to the maximum, and the outer diameter end of the shield plate 6 and the inner diameter surface of the outer ring 2 are set. It formed a labyrinth gap 10 between and.

〔Example〕

 1 and 2 show an embodiment of this invention.

The structure of the embodiment is basically the same as the structure of FIG. 5 described in the prior art, and the same portions are denoted by the same reference numerals and the description thereof will be omitted. Here, the characteristic portion will be described.

The bearing seal 5 is composed of a metal cored bar 5a and an elastic material 5b such as rubber, and a protruding piece 7 protruding outward is formed on the outer surface of the elastic material 5b forming the surface layer thereof.

The projecting pieces 7 are continuously formed on the same circumference, and the side surface 7a facing the outer ring 2 has a root portion to a tip portion.
It is an inclined surface that approaches the outer ring 2 as it goes to 7b.

The shield plate 6 is made of an annular metal thin plate, and the inner diameter end is press-fitted into the inner ring 1 and fixed. The outer diameter end of the shield plate 6 enters a circumferential groove 9 provided on both sides of the outer ring 2 and a labyrinth gap 10 is formed between the outer edge and the groove 9.

The side surface of the shield plate 6 is bent outward from the middle in the width direction, and an annular recess 8 is formed at the center of the inner side surface by this processing. When the bearing seal 5 and the shield plate 6 are mounted between the inner and outer races, the tip portion 7b of the projection piece 7 is inserted into the annular recessed portion 8. The tip end of the projection piece 7 is normally used. A labyrinth gap 11 is formed between the portion 7b and the inner surface of the annular recess 8.

Further, the amount 1 of the protrusion piece 7 entering the annular recess 8 is the displacement amount when the inner ring 1 and the outer ring 2 are tilted to the maximum, that is, the maximum amount of the bearing seal 5 and the shield plate 6 when the inner and outer rings are tilted. It is set to be larger than the separation amount, and the protrusion piece 7 is always
The distal end portion 7b of the above is inserted into the annular recess 8 so as not to come out of the shield plate 6.

Further, in the annular recessed portion 8, the inner side surface 8a and the outer side surface 8b facing the protruding piece 7 are inclined surfaces which are inclined in directions in which the inner side surface 8a and the outer side surface 8b are separated from each other toward the inner side of the bearing A. The surface is enlarged.

This embodiment has the structure as described above, and the operation will be described below.

When the bearing A of the embodiment is used to support the intermediate shaft 23 as shown in FIG. 3, the bearing A is mounted sideways in order to support the intermediate shaft 23 arranged horizontally with respect to the ground.

In such a state of use, the upper part of the bearing A is
As shown in FIGS. 2 and 3, the side surface 7a of the protruding piece 7 of the bearing seal 5 is an inclined surface that inclines downward toward the root portion.

Now, when the inner ring 1 and the outer ring 2 are tilted and the left and right projection pieces 7 and the shield plate 6 are relatively brought into contact with each other, the projection pieces 7 are separated from each other by the amount of contact and separation.
Since the amount of entry into the annular recess 8 is large, the tip portion 7b of the protruding piece 7 is always in the interior of the annular recess 8. Therefore, the gap created between the outer ring 2 and the shield plate 6
The muddy water or rainwater that has entered from 10 is received by the side surface 7a of the protruding piece 7, flows along the inclination of the side surface 7a to its root, and from the tip portion 7b of the protruding piece 7 at the upper position to the annular recess 8
Does not flow inside. The muddy water and the like flow downward along the surface of the protruding piece 7, and under the bearing, the shield plate 6 and the outer ring 2 are provided.
It is discharged from the gap created between and.

[Effects of the Invention] As described above, according to the present invention, the bearing seal and the shield plate are each formed with a projection piece continuous on the circumference and an annular recess into which the projection piece is inserted, and muddy water entering between the outer ring and the shield plate is formed. It is designed to receive rainwater and rainwater on the surface of the protruding piece, and to flow downward along the surface and discharge it to the outside, effectively preventing intrusion of muddy water etc. into the bearing seal regardless of the inclination of the bearing. It is possible to obtain stable bearing performance.

In addition, the shield plate 6 and the outer ring 2, and the shield plate 6 and the protruding piece 7
Since the double labyrinth seal is configured between the space and the space, it is possible to suppress the intrusion of muddy water and the like, and the shield plate 6 rotates in a non-contact state with other parts, so that heat generation and torque of the seal part are prevented. The increase can be prevented.

Furthermore, the inner and outer surfaces 8a and 8b of the annular recess 8 are inclined surfaces that are inclined in opposite directions, and the projection piece 7 is sandwiched between them,
The gap between the surface of the projection piece 7 and the surface of the annular recess 8 can be narrowed over the entire length, and a labyrinth sealing effect can be expected even during that time. Even if muddy water or the like enters from the clearance 10 at the tip of the projection piece 7, the muddy water is guided to the clearance 10 by the inclination of the projection piece 7 and the inner side surface 8a, and is smoothly discharged along the outer side surface 8b.

In addition, by bending the central portion of the side surface of the shield plate 6 to form the annular recessed portion 8, the deformation resistance strength of the shield plate itself can be increased, and the seal portion can be reliably protected against external force. The fixing strength between the inner ring 1 and the shield plate 6 can be increased.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing a ball bearing of an embodiment, FIG. 2 is an enlarged cross-sectional view showing a main part of FIG. 1, and FIG. 3 is a surface showing a wheel drive structure of a front engine front drive vehicle. FIG. 4 is a vertical sectional side view showing a conventional example, and FIG. 5 is a vertical sectional side view showing another conventional example. 1 ... Inner ring, 2 ... Outer ring, 3 ... Ball, 4 ... Ball rolling surface, 5 ... Bearing seal, 6 ... Shield plate, 7 ... Projection piece, 7a ... Side surface, 7b ... Tip Part, 8 ... annular recess, 1
0,11 …… Labyrinth gap, A …… Bearing.

Claims (1)

[Scope of utility model registration request] 1. Bearing seals 5 having outer diameter ends fixed to the outer ring 2 on both sides of a ball rolling surface 4 of the inner ring 1 and the outer ring 2.
And a shield plate 6 whose inner diameter end is fixed to the inner ring 1 are provided in order from the inside, and a projection piece 7 is formed on the outer surface of the bearing seal 5 so as to continuously project outward on the circumference, and the side surface of the shield plate 6 is formed. Is bent to form an annular recess 8 into which the protrusion 7 is inserted, a labyrinth gap 11 is formed between the annular recess 8 and the protrusion 7, and the outer ring side surface 7a of the protrusion 7 is a tip. Toward the outer ring 2 toward the outer ring 2, and the inner and outer side surfaces 8a and 8b of the annular recess 8 facing the protruding piece 7 are inclined surfaces in a direction away from each other toward the inner side of the bearing. Of the inner ring 1 into the annular recess 8
Of the ball bearing characterized in that a labyrinth gap 10 is formed between the outer diameter end of the shield plate 6 and the inner diameter surface of the outer ring 2 by setting the displacement larger than the displacement amount when the outer ring 2 is tilted to the maximum. Self-aligning seal structure.