CN112780688A

CN112780688A - Wheel bearing seal

Info

Publication number: CN112780688A
Application number: CN202010939716.3A
Authority: CN
Inventors: D.沙赫; V.温特
Original assignee: SKF AB
Current assignee: SKF AB
Priority date: 2019-11-05
Filing date: 2020-09-09
Publication date: 2021-05-11
Also published as: DE102019216994A1

Abstract

The invention relates to a wheel bearing seal (10) for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing, comprising a first ring (12) and an annular unit (14) having a second ring (16) made of metal. It is proposed that the ratio of the radial distance (18) which is present in space between the radially outermost point (20) of the first ring and the second ring to the maximum radial extent (22) of a region (24) of the wheel bearing seal having a point, which is obtained at the location of the wheel bearing seal having the point by a section through the wheel bearing seal in the axial direction (26) and in the radial direction (28), is greater than 0.2.

Description

Wheel bearing seal

Technical Field

The invention relates to a device according to the preamble of claim 1.

Background

From fig. 1, a wheel bearing seal for the unilateral sealing of the space between the inner ring and the outer ring of a wheel bearing is known, which has a first metal ring 54 and an annular unit 56, which has an elastomer ring 58 and a second ring 60 made of metal. On the usual running rail 62, dirt moves through the narrow opening delimited by the annular unit and the ring 60 into the wheel bearing seal and deposits radially on the sealing lip 64.

Disclosure of Invention

The object of the invention is, in particular, to provide a wheel bearing seal with improved sealing properties.

The above-mentioned object is achieved according to the invention by the features of claim 1, advantageous embodiments and refinements of the invention being found in the dependent claims.

The invention relates to a wheel bearing seal for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing, having a first ring and an annular unit with a second ring made of metal.

According to the invention, it is proposed that the ratio of the radial distance which is present in space between the radially outermost point of the first ring and the second ring to the maximum radial extent of the region of the wheel bearing seal having said point, which is obtained by a section through the wheel bearing seal in the axial direction and in the radial direction at the location of the wheel bearing seal having said point, is greater than 0.2. Improved sealing characteristics can be achieved according to the present invention. In particular, it is possible that dirt, which is formed, for example, by a liquid with abrasive particles (in particular silicates), moves out of the wheel bearing seal again after it has penetrated into the wheel bearing seal through its opening and does not remain on the sealing lip, which dirt can damage the sealing lip. In addition, it can be prevented in particular that abrasive particles enter from the outside between the dynamic sealing lip and the region on which the sealing lip is intended to bear for sealing, and mix there with the lubricant of the seal to form a lubricating gel paste, which prevents the lubricating gel paste from causing damage to the sealing lip and thus to the sealing function. In particular, a long service life of the wheel bearing in which the wheel bearing seal is installed can be achieved.

Furthermore, a wheel bearing seal for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing is proposed, having a first ring and an annular unit with a second ring made of metal, wherein the annular unit has an elastomer element which is designed to guide particles which move outward in the radial direction of the wheel bearing seal in the direction of an opening which is delimited by the annular unit and the first ring. According to the present invention, improvement of sealing characteristics can be achieved. In particular, it is possible that dirt, which may be formed, for example, by a liquid with abrasive particles, moves out of the opening and does not remain on the sealing lip, which dirt remains and may damage the sealing lip.

Furthermore, a wheel bearing seal for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing is proposed, having a first ring and an annular unit with a second ring made of metal, wherein the annular unit has at least one elastomer element with at least one first region which, in an axial section through the first region, in each case has substantially the shape of a radially inwardly directed tip. Thereby, an improvement of the sealing properties can be achieved. In particular, it is possible to achieve that dirt which has moved toward the wheel bearing seal drops or falls off in the radial direction on this region, so that penetration of dirt into the opening of the wheel bearing seal is prevented.

The elastomer element preferably has at least one second region having substantially the same shape as the first region, wherein the first region and the second region are separated from one another in the circumferential direction by an intermediate space. It is thereby possible to achieve that dirt which has penetrated into the wheel bearing seal through the opening of the wheel bearing seal can flow out of the wheel bearing seal unhindered by the effect of centrifugal force.

Furthermore, a wheel bearing seal for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing is proposed, which has a first ring and an annular unit with a second ring made of metal, wherein, at a radial end of a leg of the first ring, which leg extends substantially in the radial direction, the first ring has an annular shoulder which extends at least in sections in the axial direction toward the second ring and/or extends outward in the radial direction. Thereby, an improvement of the sealing properties can be achieved. In particular, it is possible to prevent dirt which moves radially inward or slightly obliquely relative thereto and which drips off, in particular, from the axially outer region of the annular unit from penetrating into the wheel bearing seal.

Advantageously, the shoulder forms a circumferentially extending groove. This makes it possible to achieve a particularly effective screening of dirt and an outflow of dirt.

Preferably, at least a substantial portion of the shoulder is at a lesser axial distance from the radial leg of the second ring than the free end of the axial leg of the second ring. In this way, dirt dripping from the free end or from the region adjacent to the free end and radially inward is prevented from penetrating into the opening of the wheel bearing seal.

Furthermore, a wheel bearing seal for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing is proposed, which has a first ring and an annular unit with a second ring made of metal, wherein the annular unit has at least one lip extending substantially in the axial direction, which lip is bent radially outward at its axial free end. This makes it possible for the lip to form a circumferentially extending channel which receives dirt and thus prevents the dirt from being pushed in particular against the contact surface of the lip on the first ring.

Preferably, the wheel bearing seal is formed by said annular unit and said first ring. This makes it possible to achieve a simple and inexpensive design.

Furthermore, a wheel bearing, in particular a truck wheel bearing, having a wheel bearing seal is proposed. Furthermore, a motor vehicle, in particular a truck, with a wheel bearing is proposed, wherein the ring unit rotates when the motor vehicle is in motion. Thereby, better sealing properties can be achieved.

Drawings

Further advantages are obtained from the following description of the figures. Embodiments of the invention are shown in the drawings. The figures, description and claims contain a number of combinations of features. The person skilled in the art suitably also considers these features individually and generalizes them to meaningful further combinations.

FIG. 1 shows an axial cross-sectional view through a wheel bearing seal according to the prior art;

FIG. 2 shows an axial cross-sectional view through a wheel bearing seal according to the present invention;

FIG. 3 shows a perspective view through an axial section of a further wheel bearing seal according to the invention;

figure 4 shows a perspective view in axial section through a further wheel bearing seal according to the invention with a continuous drip edge.

Detailed Description

Fig. 2 shows an axial section through a wheel bearing seal according to the invention, which is designed for single-side sealing of the space between the inner ring and the outer ring of a wheel bearing. The wheel bearing seal has a first ring 12 composed of metal and an annular unit 14 comprising a second ring 16 also composed of metal. The first ring 12 has a leg 66 which extends in the axial direction 46 and has an annular shape and, in the fully installed state of the wheel bearing seal, rests against the inner ring of the wheel bearing. Furthermore, the second ring 16 has a leg 68 which also has an annular shape and extends in the axial direction 26 and rests against the outer ring of the wheel bearing in the fully mounted state.

The radially outermost point 20 of the first ring has a radial distance 18 from the second ring. Furthermore, a region 24 of the wheel bearing seal having the point 20, which is obtained by cutting through the wheel bearing seal in the axial direction 26 and the radial direction 28 of the wheel bearing seal at the location of the wheel bearing seal having the point, has a maximum radial extent 22. The ratio between the distance 18 and the extension length 22 is greater than 0.2.

The annular unit is constituted by the second ring and the elastomeric element 30. The annular unit is designed to guide particles which move outward in the radial direction of the wheel bearing seal in the direction of the opening 32 delimited by the annular unit and the first ring. For this purpose, the elastomer element 30 has a surface 70, which is obtained in an axial sectional view by an extension section, which extends obliquely to the axial direction and to the radial direction, i.e. extends from the inner region of the wheel bearing seal outward in the radial direction, so that particles which move outward in the radial direction to the surface and which impinge on the surface are deflected in the direction of the opening 32 of the wheel bearing seal and leave the wheel bearing seal through the opening. Furthermore, depending on the size of the opening, a movement path 72 is provided for a certain portion of the penetrating dirt, which, although initially opens into the wheel bearing seal, leads the dirt out again through the opening 32 after a certain circular path.

The wheel bearing seal is comprised of an annular unit and a first ring. The wheel bearing seal may be installed in a truck, for example. If the wagon itself moves, the annular unit rotates about its axis of symmetry, so that the dirt particles move by centrifugal force onto the surface 70, for example on the lip 50 extending substantially in the axial direction. In the installed state, the free end of the lip 50 is bent radially outward, so that a circumferentially extending groove is formed between the tip of the lip and the end opposite the tip, in which groove dirt can accumulate. In the state in which dirt accumulates in the groove, if the amount of dirt in the groove is comparatively small or moderate, it can be achieved that this dirt does not reach the free end of the lip 50 and therefore does not reach the sealing contact of the lip. The liquid entering the wheel bearing seal through opening 32 assists in carrying dirt away from the wheel bearing seal.

In order to further improve the sealing, the elastomer element 30 has two further sealing lips, one of which rests against the leg 66 extending in the axial direction and the other extends axially in the direction of the interior space of the bearing and radially inward in the fully mounted state. The last-mentioned lip forms a contactless seal together with the leg 66.

Fig. 3 and 4 show alternative embodiments. Components, features and functions which remain substantially the same are denoted in principle by the same reference numerals. To distinguish the embodiments, however, the reference numerals of the embodiments in fig. 3 and 4 are added with the letter "a" or "b". The following description is essentially limited to the differences from the embodiment in fig. 2, wherein reference may be made to the description of the embodiment in fig. 2 with regard to the components, features and functions remaining the same.

FIG. 3 illustrates an alternative embodiment of a wheel bearing seal. On the axially outer end, the annular unit has first regions 34a on its elastomer element, which in an axial section through the regions each have the shape of a radially inwardly directed tip 35 a. This shape is advantageous for allowing dirt that hits the end side of the annular unit directly adjacent to the tip 35a to drip radially inward. Furthermore, the elastomer element comprises a second region 36a, which is identical in its shape to the region 34a and is likewise arranged at an axial end of the elastomer element. The region 34a and the region 36a are separated from each other in the circumferential direction by an intermediate space 38 a. Dirt particles which impinge on the surface 30a and are deflected in the direction of the opening 32a can escape from the inner region of the wheel bearing seal through the intermediate space 38a in such a way that they move substantially counter to the axial direction 26 a.

Furthermore, at the radial end 42a of the radially extending leg 44a of the first ring, the first ring has an annular shoulder 46a which extends partially in the axial direction toward the second ring and partially in the radial direction outward. In this case, the shoulder 46a forms a groove 47a which extends in the circumferential direction 40a and captures and guides dirt dripping off from the tip 35a, so that the dirt cannot enter the interior of the wheel bearing seal. Dirt can be captured in that a majority of the shoulder 46a is at a smaller axial distance from the radial leg 49a of the second ring than the free end 48a of the axial leg 51a of the second ring.

Furthermore, the annular unit comprises a lip 50a which extends substantially in the axial direction and which is bent radially outward at its free axial end 52a and, as a result, forms a groove on its radial outer side, in which groove dirt is captured which can be transported out of the wheel bearing seal as a result of the centrifugal forces acting during the rotation of the annular unit.

Figure 4 shows a further embodiment of a wheel bearing seal according to the invention. The wheel bearing seal has an elastomer element 30b which comprises a region 34b and a tip 35b, wherein the region extends over 360 ° in the circumferential direction. The only difference between the embodiment of fig. 3 and the embodiment of fig. 4 is, therefore, that there is no intermediate space 38a in the embodiment of fig. 4.

List of reference numerals

10 wheel bearing seal

12 rings

14 Ring Unit

16 rings

18 distance

20 points

22 extended length

24 region

26 axial direction

28 radial direction

30 elastomeric element

32 opening

34 area

35 tip part

36 region

38 intermediate space

40 circumferential direction

42 end of the pipe

44 side leg

46 shoulder

47 groove

48 end part

49 side leg

50 lip

51 side leg

52 end portion

54 metal ring

56 annular unit

58 elastomer ring

60 ring

62 orbit

64 sealing lip

66 side leg

68 side leg

70 surface

72 path of motion

Claims

1. A wheel bearing seal (10) for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing, having a first ring (12) and an annular unit (14) with a second ring (16) made of metal, characterized in that the ratio between a radial distance (18) which is present in space between a radially outermost point (20) of the first ring and the second ring and a maximum radial extent (22) of a region (24) of the wheel bearing seal having said point, which region is obtained by a cut through the wheel bearing seal in an axial direction (26) and a radial direction (28) at the location of the wheel bearing seal having said point, is greater than 0.2.

2. Wheel bearing seal, in particular according to claim 1, for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing, having a first ring and an annular unit with a second ring made of metal, characterized in that the annular unit has an elastomer element (30) which is designed to guide particles which move outward in the radial direction of the wheel bearing seal in the direction of an opening (32) which is bounded by the annular unit and the first ring.

3. Wheel bearing seal, in particular according to claim 1 or 2, for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing, having a first ring and an annular unit with a second ring made of metal, characterized in that the annular unit has at least one elastomer element with at least one first region (34) which, in an axial section through the first region, in each case has substantially the shape of a radially inwardly directed tip (35).

4. Wheel bearing seal according to claim 3, wherein the elastomer element has at least one second region (36) having a shape which is substantially the same as the shape of the first region, wherein the first region and the second region are separated from each other in a circumferential direction (40) by an intermediate space (38).

5. Wheel bearing seal, in particular according to one of claims 1 to 4, for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing, having a first ring and an annular unit with a second ring made of metal, characterized in that the first ring has an annular shoulder (46) at a radial end (42) of a leg (44) of the first ring which extends substantially in the radial direction, which shoulder extends at least in sections in the axial direction toward the second ring and/or extends outward in the radial direction.

6. The wheel bearing seal according to claim 5, wherein the shoulder forms a circumferentially extending groove.

7. Wheel bearing seal according to claim 5 or 6, wherein at least a major part of the shoulder is at a smaller axial distance from the radial leg (49) of the second ring than the free end (48) of the axial leg (51) of the second ring.

8. Wheel bearing seal, in particular according to one of the preceding claims, for the unilateral sealing of a space between an inner ring and an outer ring of a wheel bearing, having a first ring and an annular unit with a second ring made of metal, characterized in that the annular unit has at least one lip (50) which extends substantially in the axial direction and which is bent radially outward at its axial free end (52).

9. The wheel bearing seal according to any of the preceding claims, consisting of the annular unit and the first ring.

10. Wheel bearing, in particular a lorry wheel bearing, having a wheel bearing seal according to one of the preceding claims.

11. A motor vehicle, in particular a lorry, having a wheel bearing according to claim 10, in which the ring unit rotates when the motor vehicle is in motion.