JPS62151629A - Thrust receiving device serving as seal for bearing for cross joint - Google Patents

Abstract

PURPOSE:To maintain a sealing force between the inside and outside of a bearing even under an excessive thrust by forming a large space part which accommodates a swelled-out material and absorbing the deformation of a lip by said space part. CONSTITUTION:A second lip 10 is pushed out to a large extent and outwardly deformed due to thrust. However, a large space part 13 which is formed on the second lip 10 toward a first lip 9, accommodates and houses the pushed out part of the second lip 10, and some zone of the space part 13 filled with the moved second lip 10. Accordingly, since the movement of the volume of the second lip 10 is restricted to the space part 13 and absorbed by this space part, the sealing function between an on outer race 7 and a shaft 2 is not deteriorated either by the first lip 9 or by the second lip 10.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a bearing seal and thrust bearing device in a cross shaft joint used for an automobile steering shaft, propeller shaft, etc. By eliminating the transmission force, even if the lip that mainly receives the thrust is greatly deformed due to excessive thrust, the other lip will not be affected.

[Conventional technology]

As a conventional seal/thrust bearing device for a bearing for a cruciform joint, there is one described, for example, in Japanese Utility Model Publication No. 54-41883.

In both of these conventional devices, the first
a lip and a second lip, the first lip is in contact with the outer periphery of the bearing outer ring, and the second lip is in contact with the end face of the bearing outer ring, and these lips seal between the bearing and the cross shaft; It receives the thrust of the bearing.

[Problem that the invention seeks to solve]

However, in such conventional devices, the first
The lip and the second lip were integrally connected by an intermediate rubber-like elastic body with sufficient volume.

For this reason, for example, if the second lip is deformed due to the thrust of the bearing (especially its outer ring), the deformation may occur due to a thrust greater than the design value that should be applied when assembling the cruciform joint. When it's big enough to scratch,
The second lip may be greatly deformed and a part of its volume may be transferred to the intermediate rubber-like elastic body, and the intermediate rubber-like elastic body may receive this and protrude toward the outer circumference. Then, this protruding part pushes the first lip outward and separates it from the outer ring of the bearing, while at the same time creating a gap between the outer ring of the bearing and the boundary between the part where the protrusion occurs and the part where the protrusion does not occur in the circumferential direction. Sometimes.

When the first lip separates from the outer ring and the gap is created, the function of sealing between the inside and outside of the bearing is reduced, allowing dust and moisture to enter the outer circumference of the shaft, lubricant leaking, etc. The problem arises.

This invention was made by focusing on such conventional problems, and by eliminating the force transmission force between the two lips, the lip that mainly receives thrust is greatly deformed due to excessive thrust. The purpose is to prevent the deformation of the lip from having an adverse effect on other parts of the body.

[Means for solving problems]

The seal/thrust bearing device for a bearing for a cruciform joint according to the present invention is provided with a first
The thickness of the rubber-like elastic body covered with the reinforcing ring is reduced or the rubber-like elastic body is eliminated between the lip and a second lip made of a rubber-like elastic body and in contact with the end surface of the outer ring of the bearing. A large space is formed to block the transmission of force and to serve as an escape for the material bulging due to compression deformation of the second lip.

[Effect]

When assembling a cruciform joint, a thrust larger than the design value was applied to the bearing, and the second lip, which was backed up by a reinforcing ring, was greatly deformed and part of its volume moved outward. However, the moving portion of the second lip only enters the space, and therefore the deformation is absorbed in the space, so that it does not affect other parts such as the first lip. Therefore, even with excessive thrust, the sealing force between the inside and outside of the bearing can be maintained.

〔Example〕

1 to 3 show a first embodiment of this invention,
(2) is a cross axis, which is constructed by four axes 2 intersecting each other in a cross shape at a crossing part 3, and 4 is a local part of the axes 2. This shaft 2 is rotatably fitted through a bearing 6 to a yoke 5 of a cross-shaft joint, which is a type of universal joint.

The bearing 6 is a shell-shaped needle roller bearing, and includes a shell-shaped outer ring 7 having a bottom 71 at one end and an inward flange 72 at the other end, and a large number of needle rollers 8 disposed inside the shell-shaped outer ring 7. Consisting of This bearing 6 has rollers 8 disposed on the outer periphery of the shaft 2 so as to be freely movable, and an outer ring 7 fitted inside the yoke 5.
This forms a bearing for shaft 2. The bottom 71 of the outer ring 7 and the shaft 2
A gap t is ensured between the tip end surface and the tip surface so that the two do not come into contact with each other.

Flange 72 of outer ring 7 in bearing 6 and shoulder 4 of shaft 2
A seal/thrust receiving device according to the present invention is interposed between the shaft 2 and the shaft 2. This device includes a first lip 9 made of a rubber-like elastic body and in contact with the outer periphery of the outer ring 7, a second lip 10 made of a rubber-like elastic body in contact with the surface of the flange 72, and a second lip 9 disposed near the shoulder 4. and both lips 9 and 10 are vulcanized and bonded.
- Thrust reinforcing ring 11 for increasing rigidity.

91 is the tip of the first lip 9, 101 is the second lip 10
The first lip 9, in particular, has a larger wall thickness on the tip side than the root, thereby increasing the binding force against the outer ring 7.

The first 'J knob 9 is vulcanized and bonded to the vicinity of the outer periphery of the thrust reinforcing ring 11, and the second lip 10 is vulcanized and bonded to the surface of the thrust reinforcing ring 11 near the inner periphery on the flange 72 side. By disarranging the bonding parts of both lips 9, 10 to thrust reinforcing ring 11, both lips 9, 1
The thickness of the rubber-like elastic body 12 coated on the thrust reinforcing ring 11 is made extremely thin to about 0.2 mm between the lips 9 and 10, thereby creating a large space between the lips 9 and 10 that blocks the transmission of force. 13
is formed. In order to make the rubber-like elastic body 12 thin and at the same time ensure resistance (rigidity) against thrust force,
In this embodiment, the thickness of the thrust reinforcing ring 11 is increased.

In addition to the function of the reinforcing ring in the conventional seal-cum-thrust receiving device, the thrust reinforcing ring 11 increases the rigidity in the thrust transmission direction, and furthermore, as described above, the
This compensates for the decrease in the mass of the entire device caused by increasing the size. Note that the rubber-like elastic body 12 is attached to the first lip 9 side and the second lip 1 side during molding of this seal/thrust receiving device.
This is formed by the gap between the thrust reinforcing ring 11 and the mold formed to ensure that the rubber (fabric) goes around to the 0 side. Therefore, this part affects the sealing function and the thrust bearing function. does not affect If the rubber (dough) can sufficiently wrap around through another route, it is not necessary to form the rubber-like elastic body 12.

The space 13 is formed in order to absorb the volume of the second lip 10 moved by the deformation of the second lip 10, as will be described later.
The size of the second lip 10 is determined by conditions such as the volume of the second lip 10 and the expected amount of deformation thereof. On the other hand, the volume of the second lip 10 is set to a necessary and sufficient value in accordance with the magnitude of the thrust received by the seal/thrust receiving device, and is set to a value that is not excessively large, so that it does not have an excessive volume. 13
In relation to its size, the negative impact on other parts during its deformation is minimized as much as possible.

Therefore, in this seal/thrust receiving device, even if excessive thrust is applied due to differences in the assembly equipment 9 assembly method etc. when assembling the cross shaft joint, as shown in Fig. 3, the thrust Combined with the function of the reinforcing ring 11, only the second lip 10 is greatly deformed by the thrust, and other parts are not affected.

This is explained as follows. That is, ten.

When fitting the yoke 5 onto the shaft 2 of the character ring 1, the bearing 6
The yoke 5 is fitted onto the outer periphery of the outer ring 7 while the yoke 5 is fitted onto the shaft 2 and pressed in the direction of the intersection 3. However, when the bearing 6 is pushed in the direction of the intersection 3, the flange of the outer ring 7 72 is the seal and thrust receiver is the second lip l of the device
A flange 72 on the outer periphery of the outer ring 7 and pressed against the O
A first lip 9 is pressed near the .

In this case, when the thrust of the outer ring 7 is excessive, the distance between the flange 72 and the thrust reinforcing ring 11 becomes extremely small, and the second lip IO pressed by the flange 72 is greatly deformed. A large volume shift of IO is forced. However, since the second U knob 1O is surrounded by the shaft 2 on the inside and by the flange 72 and the thrust reinforcing ring 11 in the axial direction, it cannot be deformed in these directions and can only be deformed mainly on the outside. unable to move. Therefore, the second lip 10 is deformed so as to be largely pushed outward by the thrust;
Since a large space 13 is formed between the second lip 10 and the first lip 9, the pushed out portion of the second lip 10 escapes into this space 13 and is accommodated in the space 13. The area formed by the second lip 10 is filled in by the moved second lip 10.

However, the movement of the volume of the second J-knob 10 remains up to the space 13 and is absorbed there, so the influence of the second lip 10 does not extend to the first lip 9.
Further, a portion of the second lip 10 does not protrude significantly toward the outer circumferential direction of the flange 72.

Therefore, the first lip 9 does not separate from the flange 72, and the protruding portion of the second lip IO
There is no gap between them. Therefore, the sealing function between the outer ring 7 and the shaft 2 is not diminished by either the first lip 9 or the second lip 10, and prevents intrusion of dust, water, etc. from the outside and lubricant from the inside. Leakage can be reliably prevented.

FIG. 4 shows a second embodiment, in which the second lip 10
is made smaller, and the rubber-like elastic body (the rubber-like elastic body indicated by the reference numeral 12 in the first embodiment) covered with the thrust reinforcing ring 11 between both lips 9 and 10 is eliminated,
A thrust reinforcing ring 11 is exposed between both lips 9 and 10. Since the second lip 10 is small as described above, this seal/thrust receiving device has high rigidity in the axial direction, and the amount of volume movement due to deformation of the second lip 10 is also small. Further, the shoulder portion 4 in the thrust reinforcing ring 11
It can be seen that the thickness of the rubber-like elastic body 14 on the side surface is large, and that it is through this that the rubber (dough) wraps around within the mold during manufacturing. Reference numeral 141 denotes a hole formed in which a support is arranged to support the thrust reinforcing ring 11 within the formwork. In this embodiment, on the outer ring 7 side of the thrust reinforcing ring 11, the first lip 9 and the second lip 10 are completely separated and completely independent of each other. Therefore, there is no physical influence on the first lip 9 due to the deformation of the second lip 10. Other configurations and operations are the same as in the first embodiment.

FIG. 5 shows a third embodiment, in which the thrust reinforcing ring 11 has a radial portion 111 and an axial portion 112 in a cross-sectional shape to reduce the weight of the thrust reinforcing ring 11, and the axial portion 112 protrudes toward the second lip 10 side,
This is an example in which the thickness is substantially increased. This increases the thickness of the portion of the axial portion 112 that receives the thrust, thereby ensuring sufficient resistance (rigidity) against the thrust force, and expanding the space 13 toward the shoulder portion 4 side. (Thus, since a sufficient space 13 can be secured, the influence of deformation of the second lip 10 on other parts is further eliminated.Other configurations and functions are the same as those of the first and second embodiments. be.

FIG. 6 shows a fourth embodiment, in which the shape of the thrust reinforcing ring 11 is made to have an angular cross section in the axial direction portion 112 facing oppositely to that of the third embodiment, thereby increasing the diameter. The direction portion 111 is brought closer to the space 13 side, and the surface of the thrust reinforcing ring 11 on the space 13 side is arranged in the same manner as in the first embodiment, and is also lighter than the first embodiment. The other configurations and effects are the same as those of the first to third embodiments.

In each of the embodiments described above, the tip end 101 of the second lip 10 is sharpened as shown in the figure, but it may be made flat so that it makes surface contact with the flange 72 from the beginning. However, even in this case, it goes without saying that the second lip 10 should have a volume proportional to the thrust received.

〔Effect of the invention〕

As explained above, in the present invention, the thickness of the rubber-like elastic body covered with the thrust reinforcing ring between the first and second lips is reduced or the rubber-like elastic body is eliminated, so that the force between the two lips is reduced. The second lip is backed up by a thrust reinforcing ring. For this reason, when assembling a cruciform joint, a thrust larger than the design value is applied to the bearing, and the second lip that receives this becomes thick (deformed and some of its volume moves outward). , the moving part of the second lip only escapes into the space, and the deformation is absorbed in the space, so it does not affect other parts such as the first lip. The first lip does not move or deform due to deformation of the lip, and the second lip does not become thicker (protrudes or protrudes) toward the outer circumference of the flange.
Since there is no change in surface pressure or formation of gaps between the protruding part and the flange at the boundary between the protruding part and other parts, the first
The sealing function of the lip can be maintained as expected, and the sealing function of the second lip will not deteriorate. Thus,
Since the sealing force between the inside and outside of the bearing can be maintained even with excessive thrust, reliability can be improved in preventing dust, water, etc. from entering the shaft outer periphery and lubricant from leaking to the outside. As a result, there is no need to provide the cruciform joint assembly machine with a minute thrust control function for the bearings, which simplifies machine design, and also eliminates the need to perform extremely rigorous visual inspections after assembly. . Furthermore, since the space between the two lips is enlarged, the amount of elastic rubber required is reduced, which has the effect of reducing weight and cost.

It should be noted that, as a matter of course, the shapes of the first lip, the second lip, the shape of the thrust reinforcing ring, etc. are not limited to the examples, but depend on the conditions of use.

Depending on the bearing and the structure around the bearing, modifications may be made as appropriate within the conditions set forth in the claims.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing a first embodiment of the present invention, Fig. 2 is an enlarged view of the main part of Fig. 1, Fig. 3 is an explanatory diagram of a modification of Fig. 2, and Fig. 4 is a second embodiment. FIG. 5 is a cross-sectional view of the third embodiment, and FIG. 6 is a cross-sectional view of the fourth embodiment. l... cross axis, 2... axis, 3... intersection, 4...
・Shoulder, 5... Yoke, 6... Bearing, 7... Outer ring, 71... Bottom, 72... Flange, 8... Roller,
9...First lip, 10...Second lip, 11...
・Thrust reinforcement ring, 12...Rubber-like elastic body, 13...
・Space part. Figure 1 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] A shoulder part that is fitted onto the shaft constituting the cross shaft and is formed near the intersection of the cross shaft and an outer ring of the bearing that is fitted onto the shaft, and is located at a position close to the shoulder part. a reinforcing ring disposed, a first lip made of a rubber-like elastic material and in contact with the outer periphery of the outer ring, and a second lip made of a rubber-like elastic material and in contact with an end surface of the outer ring, and the outer ring of the bearing and the cross-shaped lip are provided. In the sealing and thrust bearing device for a bearing for a cruciform joint that seals between the shaft and receives the thrust of the outer ring, the first
The thickness of the rubber-like elastic body coated on the reinforcing ring between the second lip is reduced or the rubber-like elastic body is eliminated to block the transmission of force between both lips and to prevent expansion due to compressive deformation of the second lip. A seal and thrust bearing device for a bearing for a cruciform joint, characterized in that a large space is formed as an escape area for the material being discharged.