WO2011015176A1

WO2011015176A1 - Sealing device for a pivot bearing

Info

Publication number: WO2011015176A1
Application number: PCT/DE2010/000823
Authority: WO
Inventors: Rudolf Zeidlhack; Tim LÖSCHNER
Original assignee: Schaeffler Technologies Gmbh & Co. Kg
Priority date: 2009-08-01
Filing date: 2010-07-15
Publication date: 2011-02-10
Also published as: DE102009035739A1

Abstract

The invention relates to a sealing device for radial or axial bearings, wherein a first and a second rotary element (1,2) are pivotably mounted relative to one another about an axis of rotation, with or without the interposition of rolling elements (3), comprising a first sealing element (4,4a) associated with the first rotary element (1) and a second sealing element (5,5a,31,31a,32) associated with the second rotary element (2), wherein the first sealing element has a first and a second elastic sealing lip (16,16a), which engage in a tong-like manner on two sealing surfaces of the second sealing element (5,5a), which lie opposite each other on the second sealing element, and wherein the sealing lips can be slid relative to the sealing surfaces substantially perpendicularly to the axis of rotation (6) in the case of a radial bearing and substantially parallel to the axis of rotation (6') in the case of an axial bearing.

Description

Name of the invention

Seal device for a pivot bearing

description

Field of the invention

The invention is in the field of mechanical engineering and tribology, that is the surface design with special consideration of wear phenomena.

It is particularly the use in pivot bearings in the foreground, which are exposed to a special surface load. Rotary actuators of this type can, for example, be designed as radial or axial bearings and be present either in the form of plain bearings or roller bearings.

In designing such bearings, in addition to minimizing friction, reducing wear and extending service life are at the forefront. Basically, it is helpful for such camps, if they are encapsulated, that is sealed off from the environment.

For this purpose, a variety of sealing devices in the form of shields or elastic sealing lips are already known.

For example, from the German patent application DE 3602051 A1 a rolling bearing is known, which is sealed by an elastic sealing lip, which covers the space between the two bearing rings and is attached to a first of the bearing rings. The sealing lip is the continuation of an elastic, rectangular in cross-section strand, which is inserted into the groove of a bearing ring.

The sealing lip touches on the mating ring a sealing surface of an inserted sealing layer, which is optimized for the requirements of the seal in rubbing contact.

The main disadvantage of this known sealing device is that the sealing lip is pressed directly perpendicular to the contact surface of the mating ring and rests there rubbing and sealing. This can be a problem when the bearing rings are slightly tilted against each other by stressing the bearing, since then on the side of the sealing device, the sealing lip under higher pressure, the corresponding frictional forces between the sealing lip and the counter surface increase and the region of the sealing lip, the Gasket is applied, changes.

If tilting of the bearing takes place in the opposite direction, then, depending on the bias of the sealing lip, it may also happen that the sealing lip separates from the opposing surface.

The present invention is based on the background of the prior art, the task to provide a sealing device, the reliable and with low frictional forces a rotary bearing seals and in particular compensates for tilting or displacements of the bearing rings against each other. The object is achieved with the features of the invention according to the patent claim 1 or claim 2.

This is first explained in the case of a radial bearing. It is provided a first and a second rotary element, which may be formed, for example, as a bearing rings. These are rotatable about an axis of rotation against each other, in the case of a plain bearing without the interposition of rolling elements, otherwise with the interposition of rolling elements, which may be formed, for example, as balls or rollers. The first rotary element is associated with a first sealing element while the second rotary element is associated with a second sealing element. The first sealing element has a first elastic sealing lip, which bears sealingly and transversely to the axis of rotation on a transverse to the axis of rotation sealing surface of the second sealing element. This means that the sealing lip in the case of a radial bearing in the radial direction of the bearing on the counter surface, that is, the sealing surface of the second sealing element is displaceable.

This tilting of the sealing elements / bearing rings can be compensated without the sealing lip lifts off the sealing surface or is deformed substantially elastic compared to the ideal state.

In the case of a thrust bearing, the first sealing element is applied exclusively

Surface regions of the second sealing element, the coaxial with the axis of rotation, that is parallel to this and extend in the azimuthal direction. The first sealing element bears sealingly against a correspondingly aligned sealing surface of the second sealing element with a first elastic sealing lip and is displaceable on the sealing surface in parallel with the axis of rotation in order to compensate for tilting of the bearing.

With reference to claim 2, the sealing device provides that the first sealing element has a first and a second elastic sealing lip, the pliers like attack on two sealing surfaces of the second sealing element, which are opposite to each other on the second sealing element, wherein the sealing lips relative to the sealing surfaces in Trap of a radial bearing substantially perpendicular to the axis of rotation, in the case of an axial bearing substantially parallel to the axis of rotation of the bearing are displaceable. The provision of two sealing lips creates an additional sealing barrier for the bearing, which further improves the partitioning towards the bearing exterior. Due to the forceps-like configuration, the pressure forces of the individual sealing lips can be oriented in opposite directions toward or away from one another so that the forces on the first and second sealing elements are neutralized. In a tilting movement of the rotary elements against each other when the support of one of the sealing lips is less solid, the other sealing lip is pressed correspondingly stronger against its corresponding counter surface, so that a good seal of the bearing is guaranteed in each case.

Advantageously, corresponding sealing elements may also be provided in pairs on both sides of the rolling elements or sliding surfaces in order to seal the bearing on both sides. Furthermore, it can be advantageously provided that the sealing lips each have legs which extend in mirror-symmetrical relationship to each other substantially in the cross-section of the first sealing element. The thighs can also at least partially advantageously parallel to each other.

It can also be provided that the second sealing element is formed by a web. In this case, the two sealing lips engage on both sides of the web on this and are pressed resiliently against each other by means of mutually directed pressure forces on the web.

The web can be designed, for example, as a round or rectangular profile or as a triangular or polygonal prismatic profile and consist of steel, in particular hardened steel or highly tempered steel, for example as a drawn round steel, or an otherwise hardened metal alloy. The web is advantageously particularly smoothed to minimize friction. In this case, the web can be inserted into a groove in the first rotary element, and soldered into this, glued or held in this elastic in a press fit. The strand of the second sealing element is advantageously closed annularly and connected at the ends, for example by soldering, gluing or welding.

Alternatively, the second sealing element may also be formed as a groove extending, for example, in a component inserted in the second rotary element. The component may consist of a suitable material such as hardened steel. In this case, the legs of the first sealing element are designed in the form of a spreading forceps and the pressure forces on the side walls of the groove are directed away from one another.

The first sealing element is preferably made of an organic material, in particular of a rubber or rubber-like material. It may, for example, also consist of polyamide or PEEK, a thermoplastic polymer or another suitable plastic. It may be closed annularly preferably by gluing the ends. In order to maintain the pressure forces, a reinforcing element, which consists of a stiffer material than the first sealing element, for example of a metal, can be integrated into the first sealing element. The reinforcing element may be formed, for example, as a metal clip, the legs of which may advantageously extend to the legs of the first sealing element or even partially into it.

The first sealing element is preferably produced as a strand, closed annularly and the ends of the sealing element are advantageously connected to each other by gluing or vulcanization.

The invention relates, in addition to a sealing device as described above, to a bearing with a sealing device, which is formed according to the features of the invention described.

Finally, the invention also relates to a method for producing a bearing with a sealing device as described above, in which initially the rotary elements are completed and treated end and in which thereafter the sealing elements are inserted.

This means, for example, if the rotary elements are galvanized, for example in the form of bearing rings, that the corresponding sealing elements are introduced only after galvanizing in the bearing rings.

The advantages of the invention are that the sealing elements can be made of suitable materials, which are resistant to wear in particular against sliding friction. In addition, they can be particularly resistant to corrosion, since they are at least partially exposed to the environmental influences from the warehouse exterior. The second sealing element can therefore for example consist of a stainless, highly tempered and hardened steel. It can thus be used for the profiles of the first and second sealing element cost-prefabricated by the meter, which is bent and cut to length on suitable machines, after which the joints are connected and the joints are smoothed.

Another advantage of the invention is that the sealing elements can be replaced independently of the rotating elements.

The invention is illustrated below with reference to a drawing and explained below.

It shows

Figure 1 in cross-section two bearing rings with two on both sides of rolling elements provided sealing elements;

FIG. 2 shows the installation of a first sealing element on a second one in FIG

Cross section round sealing element in neutral position; Figure 3 shows the system of the sealing elements of Figure 2 in a tilted

Storage position;

Figure 4 shows another embodiment of a bearing in cross section; FIG. 5, in cross-section, a radial / axial bearing with double-sided seal,

Figure 6 in cross section a bearing, in which the second sealing element as

Groove is formed and Figure 7 in cross section a bearing, in which the second sealing element as

Prism is formed. Figure 1 shows in a cross section a bearing with two formed as a bearing rings rotary elements 1, 2, wherein the first rotary member is denoted by 1, the second rotary member with 2. The first rotary member / bearing ring is on both sides of the rolling elements 3 each have a first sealing element 4a, which consists of a rubber-like material and is inserted in a circumferential groove of the first bearing ring 1. The first sealing element 4 is a respective second sealing element 5,5a arranged opposite one another and assigned to the second rotary element 2. The second sealing element 5, 5a is formed as a circular cross-section round strand-shaped steel profile, which is also inserted into a circumferential groove of the second rotary member 2.

The bearing shown may be formed for example as a radial bearing. In this case, the axis of rotation is shown schematically in broken representation in the lower part of the figure and denoted by 6. However, the bearing can also be designed as a thrust bearing, in which case the axis of rotation runs perpendicular to the bearing rings and is shown in an interrupted representation and provided with the reference numeral 6 '.

In the figure, a rolling element is shown in the form of a sphere and designated 3. The ball 3 rolls between the bearing surfaces 8 and 9, wherein the Lagerflächenkonstellation is sealed off by the sealing elements 4,4a, 5,5a from the outside of the warehouse.

On both sides of the rolling elements 3, sealing elements 4, 4a, 5, 5a are provided, which cause a foreclosure on both sides of the bearing and are advantageously of identical construction. The interaction and the contact between the first sealing element 4 and the second sealing element 5 are shown only schematically and geometrically inaccurate in FIG. A more detailed representation can be seen from FIG.

There, in the upper part, the first sealing element 4 is shown, which has two sealing lips 16, 16a, which bear against the web 5 on both sides, which constitutes the second sealing element. The pressing forces of the sealing lips 16, 16a are directed towards one another inwardly and represented by the arrows 20, 20a. It should be noted that the sealing device can also have only one of the sealing lips 16, 16a. It is important that the sealing lip relative to the web 5 in the direction of the arrow 21 is displaceable and thus relative movements of the rotary elements 1, 2, in particular tilting movements against each other without significant change in the pressing force on the web 5 can compensate.

However, the embodiment with two sealing lips 16, 16a is particularly advantageous. FIGS. 2 and 3 additionally show a reinforcing profile 7 made of metal, which is integrated in the sealing element 4 and extends into the legs 30, 30a of the sealing lips 16, 16a.

FIG. 3 shows a position in which the first sealing element 4 is tilted counterclockwise relative to the second sealing element 5 by an angle α, which is approximately a tilting of the first bearing ring 1 relative to the second bearing ring 2 in the direction of the arrow 22 in Figure 1 corresponds. Simultaneously with the tilting movement of the sealing elements against each other, a shift of the first sealing element 4 to the second sealing element 5 occurs. On the opposite side of the rolling elements 3 is done according to the figure 1 between the sealing elements 4a, 5a a kind of tilting, wherein the first sealing element 4a there is a little away from the second sealing element 5a. However, this displacement movement is compensated without Schwierigkei- by a relative displacement of the sealing lips 16, 16a relative to the web 5 without the pressure forces change noticeably. A seal is thus still ensured.

FIG. 4 shows a configuration in which the first sealing elements 4, 4a have sealing lips with legs that diverge from each other, each of which surround a web 5, 5a with a rectangular cross-section.

The representation is in turn only schematically and in more detail in the enlarged detail of Figure 4. Again, the sealing lips of the first sealing element 4, 4a engage on side faces of the second sealing element 5, 5a, which in the case of a radial bearing extend substantially perpendicular to the axis of rotation, but at least transversely. By a transverse course, for example, an angular range between the axis of rotation and the area between 90 and 60 ° is meant.

If it is a thrust bearing, the side surfaces of the second sealing elements 5, 5a are substantially parallel to the axis of rotation or coaxial to this, with angular deviations, which should also be a maximum of +/- 30 °.

FIG. 5 shows an embodiment in which the sealing devices 4, 4a, 5, 5a according to the invention are used in a radial bearing. There are between the first rotary member 1 and the second rotary member 2 obliquely mounted rolling elements 25, 26 are provided there. Since these have a space requirement, which goes laterally beyond the extension of the first rotary element 1 addition, a web 27, 28 attached to this and attached, for example by means of a screw, in the circumferential web 27, 28 each within a groove, the first sealing elements 4, 4a are recessed. These act as described above in a similar manner with the second sealing elements 5, 5a together. Despite the necessary additional webs 27,28 the total cost and space requirements of the bearing including the seal is minimized.

FIG. 6 shows the embodiment of a bearing with two first sealing elements 4, 4a and two second sealing elements, each of which is designed as an annular component 32 having a groove 31, 31a. The sealing lips of the first sealing elements lie against the walls of the grooves.

In FIG. 7, a bearing is shown in cross-section with first sealing elements 4, 4a, each of which faces a second sealing element 17, 17a in the form of a prism-shaped strand. The prism is rectangular in cross-section, wherein a rectangular part of the prism is embedded in a groove of the second rotary element and a symmetrical roof-like double bevel is available as a contact surface for the sealing lips of the first sealing elements 4,4a. The invention allows, in particular pliers-like design of the first sealing element and corresponding formation of two sealing points on both sides of the bearing hermetic encapsulation of bearings, which is insensitive to tilting of the bearing parts both in their sealing effect and in the development of frictional forces. In addition, the friction partners of the sealing device are independent of the rotary elements / bearing rings manufactured and optionally also independently of these replaceable. LIST OF REFERENCE NUMBERS

1.2 rotary elements

3 rolling elements

4, 4a, 5,5a, 17,17a sealing elements

6,6 'rotation axis

7 reinforcement profile

8.9 storage areas

10.11 sealing surfaces

16,16a sealing lips

20, 20a pressure forces of the sealing lips

21 Displacement direction of the sealing lip

22 Tilting direction of the first bearing ring

25,26 obliquely mounted rolling elements 27,28 bridge

30,30a thighs

31,31a groove

32 component with groove

Claims

claims

1. A sealing device for a radial or a thrust bearing, in which a first and a second rotary element (1, 2) about a rotation axis (6,6 ') against each other rotatable with or without the interposition of rolling elements (3) are mounted, with a the first rotary element (1) associated first sealing element (4,4a) and a second rotary element (2) associated second sealing element (5,5a), wherein the first sealing element (4,4a) exclusively on transversely to the axis of rotation (6) extending surface areas in the case of a radial bearing, and wherein the first sealing element (4, 4a) extends exclusively on surface regions of the second sealing element (5, 5) extending substantially parallel and azimuthal to the rotation axis (6 '). 5a) is applied, as long as it is a thrust bearing and wherein the first sealing element has a first elastic sealing lip (16,16a), the sealing on a sealing surface of the second sealing element and in the case a radial bearing displaceable transversely to the axis of rotation, in the case of an axial bearing substantially parallel to the axis of rotation slidably. 2. Sealing device for radial or thrust bearing, in which a first and a second rotary element (1,

2) about an axis of rotation (6,6 ') against each other rotatable with or without the interposition of Wälz- Bodies (3) are mounted with a first rotary element (1) associated first sealing element (4,4a) and a second rotary element (2) associated with the second sealing element (5,5a), wherein the first sealing element has a first and a second elastic sealing lip (16,16a), the tongs on two sealing surfaces of the second

Sealing element (5,5a) attack, which are opposite to each other on the second sealing element, and wherein the sealing lips relative to the sealing surfaces in the case of a radial bearing substantially perpendicular to the axis of rotation (6) and in the case of an axial bearing substantially borrowed parallel to the axis of rotation (6 ') are displaceable.

3. Sealing device according to claim 1 or 2, characterized in that on both sides of the bearing surfaces of the bearing in each case a first and a second sealing element (4, 4a, 5, 5a) are provided.

4. Sealing device according to claim 2 or 3,

characterized in that the sealing lips (16,16a) each have legs (30,30a) which extend substantially in cross-section mirror symmetry to each other.

5. Sealing device according to claim 4,

characterized in that the legs (30,30a) at least partially parallel to each other.

6. Sealing device according to claim 1 or one of the following, characterized in that the second sealing element (5,5a) is formed by a web.

7. Sealing device according to claim 6,

characterized in that the web is formed as a round or rectangular profile.

8. Sealing device according to claim 7,

characterized in that the web is inserted into a groove in the first rotary element.

9. Sealing device according to claim 1 or one of the following, characterized in that the second sealing element as a groove (31, 31 a) is formed.

10. Sealing device according to claim 9,

characterized in that the groove extends in a loaded in the second rotary member (32).

11. Sealing device according to claim 1 or one of the following, characterized in that the first sealing element (4,4a) consists of an organic material, in particular rubber or a rubber-like material.

12. Sealing device according to claim 11,

characterized in that the first sealing element (4, 4a) has an amplifying element (7) made of a stiffer material than the first sealing element.

13. Pivot bearing with a sealing device according to one of claims 1 to 12.

14. A method for producing a bearing with a sealing device according to one of claims 1 to 12,

characterized in that first the rotary elements (1, 2) are finished and finally treated and that thereafter the sealing elements (4, 4a, 5, 5a, 31, 31a, 32) are connected to the rotary elements.