DE9301361U1 - Axial seal, especially for rollers or similar. - Google Patents

Description

Axial seal, especially for rollers or similar

The invention relates to an axial seal, in particular for rollers or the like according to the preamble of claim 1.

Such axial seals are required to protect bearings on a shaft against contamination. The seals usually work according to the principle of gap sealing and are intended to protect against dust and splash water. In addition, an external thrust washer is provided for rollers, for example, which prevents the penetration of coarse dirt particles and at the same time forms a thread guard. This thread guard is essential because the bearings of rollers can be destroyed very quickly by packaging cords etc. Another disadvantage here is that the position of the thrust washer, e.g. in rollers, can be changed by impacts from the outside, so that the seal

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Accounts:

SaI. Oppenheim jr. &Cie.. Cologne (bank code 370 302 00) Account no. 10 Deutsche Bank AG, Cologne (bank code 37070060) Account no. 1165018 Postgiro Cologne (bank code 370100 50) Account no. 654-500

is compressed and slips out of position or is subjected to greater wear, so that after a short time the bearing is no longer protected and becomes inoperable.

The conventional gap seals also have the disadvantage that they only protect against splash water, so that the bearings can be damaged when high-pressure cleaning equipment is used.

The invention is based on the object of creating an axial seal, in particular for use in rollers, which is largely insensitive to shock loads and can be subjected to pressurized water.

The features of the main claim serve to solve this problem.

The axial seal according to the invention creates a cavity for a sealing ring and maintains a defined wall distance from the bearing. This enables the use of a sealing ring that is constantly in contact with the sealing surfaces on the thrust washer and on the bearing with the same preload, so that the bearing is protected from pressurized water from high-pressure cleaning devices. The axial seal is also highly protected against external shock loads, since the thrust washer is precisely fixed in its position on the shaft part relative to the bearing.

Preferably, the sealing ring is essentially V-shaped and symmetrical in cross section. Such a symmetrical cross section extending radially

The V-shaped design of the sealing ring on the outside ensures that essentially the same sealing force is exerted on both sealing surfaces. The V-shaped design of the sealing ring allows subsequent greasing of the bearings from the inside without any assembly work.

The radially outward-projecting wall of the thrust washer can be tapered axially towards the bearing. A conically designed thrust washer enables constant centering of the sealing ring during operation.

In a preferred embodiment, the shaft part consists of a bearing bush. Such a bearing bush is easy to manufacture, easier to assemble, independent of bearings and easily replaceable.

The bearing bush can also be made in one piece with the thrust washer. With a bearing bush made in one piece with the thrust washer, the assembly effort is reduced even further.

In one embodiment, the thrust washer is seated with a shoulder on the shoulder of the shaft part. The thrust washer can be pushed onto the shaft part with a clearance, sliding or press fit and is given a high level of strength by the radial seat on the shoulder of the shaft part, which protects the thrust washer as far as possible against deformation in the event of impacts.

The sealing ring can also be mounted floating in the cavity. The floating arrangement of the sealing ring allows the rotation speed of the sealing ring to be halved and thus the wear of the sealing lips to be evenly distributed over both sealing lips.

-A-

Alternatively, the sealing ring sits on the shoulder of the thrust washer. The advantage of this alternative is that the sealing ring and thrust washer form a complete assembly unit.

Preferably, the sealing ring is made of a polyurethane with a high ε-modulus, e.g. Aclathan.

It can also be provided that the collar of the thrust washer engages in an annular groove in the shaft part. In this case, the thrust washer is pulled over the shaft part without a step until the collar of the thrust washer snaps into the annular groove.

In the following, embodiments of the invention are explained in more detail with reference to the drawings.

Show it:

Fig. 1 shows a first embodiment of the axial seal according to the invention with a bearing bush provided with a shoulder,

Fig. 2 a second embodiment of the axial seal with floating arrangement of the sealing ring, and

Fig. 3 a third embodiment of the axial seal with a bearing bush in which the thrust washer sits in an annular groove, and

Fig. 4 shows a fourth embodiment with a thrust washer integral with the bearing bush.

The embodiment shown in Fig. 1 shows the application of the axial seal in a roller 1 with a roller lining 5 attached to a bearing carrier 3. The bearing carrier 3 accommodates a bearing 6 with its outer bearing shell at each of its axial ends. A spacer bush 7 is arranged between the inner bearing shells of the bearings 6. The bearings sit with their inner bearing shells on a shaft part 4, e.g. a shaft (not shown) or a bearing bush 18 for each bearing 6, as shown in the embodiments. The bearing bushes 18 can in turn accommodate a shaft (not shown).

The bearings 6 are offset slightly axially inwards with respect to the roller 1 in order to enable the bearings to be sealed to the outside using the axial seal.

The axial seal preferably consists of a symmetrical sealing ring 2 made of aclathane with a V-shaped cross-section, which is arranged between a thrust washer 8 and the bearing 6. The sealing ring 2 opens radially outwards in a V-shape and rests with its sealing lips 11 on the one hand on the thrust washer 8 and on the other hand on the outer bearing shell of the bearing 6. When installed, the sealing lips 11 are pre-tensioned and prevent the ingress of dirt and water. When the cavity 16 is pressurized from the outside, the pressure of the sealing lips 11 on the sealing surfaces on both sides is even increased, so that a reliable seal is also achieved against pressurized water.

The sealing ring 2 and the thrust washer 8 interact with the shaft part 4 and the bearing bush 18. The

For this purpose, the shaft part 4 or the bearing bush 18 have a stop 9, which in the embodiment examples of Figs. 1 and 2 consists of a radially projecting shoulder 10 of the bearing bush 18 and in the embodiment 3 of an annular groove 22 in the shaft part 4 or in the bearing bush 18.

The bearing bush 18 is simple, e.g. made of sintered metal, easy to assemble and easy to replace. The thrust washer 8 has a shoulder 20, which sits radially on the shoulder 10 of the bearing bush 18 and gives the thrust washer a high level of stability. The sealing ring 2 can in turn sit on this shoulder 20 or, as shown in Fig. 2, be mounted floating in the cavity 16 formed between the thrust washer 8 and the bearing 6. The cavity 16 is preferably filled with grease.

The thrust washer 8 has a radially inwardly projecting collar 12, which in the embodiments of Figs. 1 and 2 rests against the shoulder 10 and in the embodiment of Fig. 3 engages in the annular groove 22. The collar 12 can snap into the annular groove 22 with radial preload or be pushed onto the bearing bush 18.

A wall 14 of the thrust washer 8 extends radially outward from the shoulder 20 and is preferably inclined conically axially inward toward the bearing 6. The conical inclination of the wall 14 ensures permanent centering of the sealing ring 2, particularly in the embodiment of Fig. 2 with a floating arrangement of the sealing ring 2.

Fig. 4 shows an embodiment in which the thrust washer 8 is in one piece with the bearing bush 18. In this case too, the bearing bush 18 has a shoulder 10 which serves as a stop for the bearing 6.

Alternatively, instead of the shoulder 10, an annular web or an annular groove 22 with a snap ring can be provided in the bearing bush 18 which is integral with the thrust washer 8 as a stop for the bearing 6.

The spacer bushing 7 has an opening 15 which serves to regrease the bearings via a grease chamber 17. The sealing lips 11 of the sealing ring allow the grease to pass through the bearing 6 and past one of the sealing lips to the outside, whereby any dirt in the cavity 16 can be pressed out.

Claims (11)

Q _ Claims 1. Axial seal, in particular for rollers or the like, with a seal and a thrust washer,
characterized, that the shaft part (4) has a stop (9) against which the thrust washer (8) rests axially with a radially inwardly projecting collar (12), that the collar (12) of the thrust washer (8) forms a stop for the bearing (6), and that the thrust washer (8) with a radially outwardly projecting wall (14) forms a cavity (16) for the seal in the form of a sealing ring (2) with a defined wall distance from the bearing (6). 2. Axial seal according to claim 1, characterized in that the sealing ring (2) is essentially V-shaped and symmetrical in cross section. 3. Axial seal according to one of claims 1 or 2, characterized in that the radially projecting wall (14) of the thrust washer (8) is conically inclined axially towards the bearing (6). 4. Axial seal according to one of claims 1 to 3, characterized in that the shaft part (4) consists of a bearing bush (18). 5. Axial seal according to one of claims 1 to 4, characterized in that the stop (9) of the shaft part (4) is formed by a shoulder (10). 6. Axial seal according to one of claims 1 to 5, characterized in that the stop (9) of the shaft part (4) is formed by an annular groove (22) of the shaft part (4). 7. Axial seal according to one of claims 1 to 6, characterized in that the thrust washer (8) is seated radially on the shaft part (4) with a shoulder (20). 8. Axial seal according to one of claims 1 to 7, characterized in that the sealing ring (2) is mounted in a floating manner in the cavity (16). 9. Axial seal according to one of claims 1 to 8, characterized in that the sealing ring (2) sits on the shoulder (20) of the thrust washer (8). 10. Axial seal according to one of claims 1 to 9, characterized in that the sealing ring (2) consists of a polyurethane with a high ε-modulus, e.g. Aclathan. 11. Axial seal according to one of claims 1 to 10, characterized in that the bearing bush (18) is integral with the thrust washer (8).