WO2015067364A1

WO2015067364A1 - Wiper arrangement and/or sealing arrangement, and wiper and/or sealing ring therefor

Info

Publication number: WO2015067364A1
Application number: PCT/EP2014/002967
Authority: WO
Inventors: Gonzalo Barillas; Steve Cowell
Original assignee: Carl Freudenberg Kg
Priority date: 2013-11-06
Filing date: 2014-11-06
Publication date: 2015-05-14
Also published as: DE102013018513A1

Abstract

The invention relates to an arrangement comprising a first machine element (1), which on the outer circumferential side is encircled by a second machine element (2), wherein a clearance exists between the first machine element (1) and the second machine element (2) and wherein in the gap (3), which is formed by said clearance, a wiper (4) and/or a sealing ring (5) is arranged. The wiper (4) has at least one wiper lip (6) and/or the sealing ring (5) has at least one sealing lip (7). The wiper lip (6) and/or the sealing lip (7) sealingly contacts a surface of the first (1) or of the second machine element (2) to be sealed, wherein the wiper (4) is accommodated on the second (2) or on the first machine element (1). The wiper (4) and/or the sealing ring (5) are accommodated axially sealingly and in the radial direction (9) in a floating manner on the second (2) or the first machine element (1) by way of a receptacle (8).

Description

Wiper assembly and / or seal assembly and scraper and / or seal for this description

Technical area

The invention relates to arrangements, comprising a first machine element, which is on the outer circumference side of a second machine element spaced apart, wherein in the gap formed by the distance a

Scraper and / or a sealing ring are arranged, wherein the scraper at least one wiper lip and / or the sealing ring have at least one sealing lip, wherein the wiper lip and / or the sealing lip sealingly contact a surface to be sealed of the first or second machine element and wherein the scraper and / or the sealing ring on the second or first

Machine element are added.

State of the art

Such arrangements with stripping rn and / or sealing rings are well known. Such arrangements are used for example in hydraulic cylinders for use, wherein by the scraper and / or sealing ring in

translational direction of reciprocating rod is sealed. A scraper usually ensures that impurities, for example water or ice, are not taken into the hydraulic cylinder with the bar entering the hydraulic cylinder. When retracting rod, the scraper ensures that impurities, water or ice are stripped when retracting the rod from the surface to be sealed, usually a thin lubricant film for lubrication of the scraper remains on the surface to be sealed.

In contrast, a sealing ring ensures that the medium to be sealed remains inside the hydraulic cylinder and does not get into the environment. In the arrangement described above, the scraper and the

Seal come as each separately generated item for use or as a combination element in which the scraper and the sealing ring are combined as a unit. In the prior art, it is common that the scraper or the sealing ring is received stationary on one of the machine elements, so moved with its inclusion so relative to this machine element neither in the axial nor in the radial direction.

For applications in which the sealed against each other

Move machine elements in the radial direction relative to each other, these radial deflection movements of the two machine elements relative to each other solely by the flexibility of the wiper lip and / or the

Sealing lip to be bridged. The mechanical loads on the

Wiper lip and / or the sealing lip are undesirably high and it can come as a result of material fatigue malfunction and failure of the arrangement.

If the radial deflections are greater than the elasticity of the wiper lip and / or the sealing lip in the radial direction, there is also the risk that there will be a radial gap between the surface to be sealed

to be sealed machine element and the wiper lip and / or the Sealing lip results and thereby sealed medium as leakage undesirably enters the environment.

Presentation of the invention

The invention has the object of further developing arrangements of the known type such that even with large radial deflection movements of the two machine elements to be sealed against each other

mechanical stresses on the scraper and / or the sealing ring are reduced to a minimum and that in such deflecting movements the lips of scraper and / or sealing ring to seal the surface of the

Always touch the machine element and any leakage will be avoided.

This object is achieved by the arrangements according to one of claims 1 to 3. In advantageous embodiments, the claims referring back refer to it. To achieve the object, it is provided that the scraper and / or the sealing ring comprise a receptacle and are received by the recording axially sealing and floating in the radial direction of the second or first machine element.

It is advantageous that the scraper and / or the sealing ring, largely independent of the size of the radial deflection movement of the two

Machine elements relative to each other during the intended use of the arrangement are always exposed to consistently low mechanical loads, because the radial deflection movements of the two machine elements are compensated relative to each other by the floating recording. Regardless of the radial deflection movements of the two

Machine elements relative to each other, enclose the wiper lip and / or the sealing lip with the surface to be sealed substantially

constant radial bias, so that, viewed in the circumferential direction of the scraper and / or sealing ring, results in a uniform distribution of the mechanical stress of the respective lips. Due to the even load and the small local deformation of the lips results in only minimal abrasive wear, so that the arrangements consistently good performance characteristics have a long service life.

The first machine element may be formed by a rod or shaft, the second machine element by a housing. The housing may for example be the housing of a hydraulic cylinder, wherein the housing may comprise a front cover, in which the scraper and / or the sealing ring are received axially sealing and floating in the radial direction. By the floating mounting of the scraper and / or sealing ring on one of the machine elements to be sealed against each other and the possibility that the scraper and / or the sealing ring and the

Machine element in the radial direction can move relative to each other, the respective geometry of the lips of scraper and / or sealing ring also practically does not change relative to the surface of the machine element to be sealed, when the machine elements are deflected in the radial direction relative to each other. For the scraper result and / or the seal result, this is the advantage to be emphasized. Even if the two machine elements are deflected maximally to each other in the radial direction, the angle of the lip geometries change only negligible, so that the performance properties are consistently good even in such a case. It can be provided that the scraper and the sealing ring are each formed as separately produced items.

The scraper and the sealing ring can each alone in one

Arrangement apply.

According to another embodiment, there is the possibility that the scraper and the sealing ring in the same arrangement are used. In such a case, it may be provided that the scraper and the sealing ring, although received by the same machine element, but are spatially separated from each other.

According to an advantageous embodiment, it may be provided that the scraper and the sealing ring are combined in a combination element, wherein the combination element comprising the scraper and the sealing ring comprises a single receptacle and by this recording axially sealing and floating in the radial direction on the second or first machine element is received. Such an embodiment is in production engineering and economic terms of hervorzuhebendem advantage. In addition, the assembly of such a combination element on the second or first

Machine element to which it is added, particularly simple.

The scraper and the sealing ring may be integrally merging into each other and / or formed of the same material. For many applications, it has proven to be advantageous if the scraper and the sealing ring are integrally merging into each other and formed of the same material. The

Production of such a combination element is particularly simple and inexpensive.

For some applications, it may be useful if the scraper and the sealing ring are indeed integrally formed merge into one another, but consist of different materials. The materials can be adapted particularly well to the particular circumstances of the application. Thus, for example, the material of the scraper can be adapted to the environmental conditions of the arrangement, without that would have an adverse effect on the performance characteristics of the sealing ring, which then consists of another, also particularly suitable material.

According to an advantageous embodiment, it may be provided that the receptacle is formed integrally with the scraper and / or the sealing ring. In comparison to a recording that is generated separately and then connected to the scraper and / or the sealing ring, has such

Design manufacturing and economic advantages. The receptacle can for example be integrally formed in the material of which the scraper and / or the sealing ring consist.

The receptacle preferably has a maximum radial adjustment path which is> the maximum radial deflection of the two machine elements relative to each other. In such a ratio of radial displacement to radial deflection is advantageous that the mechanical stress on the scraper and / or the sealing ring during the entire

the intended use of the arrangement practically never changes, regardless of how strongly the two machine elements are deflected relative to each other.

In general, there is also the possibility that the maximum radial travel is smaller than the maximum radial deflection of the two machine elements relative to each other. By such a configuration, the mechanical loads on the scraper and / or the sealing ring are indeed reduced, but the performance characteristics are not as advantageous as previously described. Therefore, the ratio of maximum radial displacement to maximum radial deflection of the two machine elements relative to each other be at least 1.

The receptacle can be formed by a substantially U-shaped groove having a congruent designed and extending in the radial direction projection of the second or first

Machine element axially sealing and radially enclosing floating. Such a groove and such a projection are simple and inexpensive to produce and the function "floating recording of the scraper and / or sealing ring on the second or first machine element" is particularly reliable and good, even during a long period of use of the arrangement.

The groove preferably has two static on its radially open side

Sealing edges, which touch the projection axially on both sides in each case under axial bias sealing. Through these static sealing edges

encloses the U-shaped receptacle of the scraper and / or sealing ring, the adjacent adjacent end faces of the projection, even then axially sealed, when the projection and the receptacle in the radial direction relative to each other to move back and forth.

The groove has end faces, one of which, based on the other, may be conical, such that the groove bottom of the groove has an extension in the axial direction, that the sealing edges have an axial distance from each other and that the extension is smaller than the distance is.

Due to the conical design is advantageous that the scraper and / or the sealing ring always centered automatically on the congruent designed, also conical projection. The assembly of the sealed

Machine element is simplified. The scraper and / or the sealing ring may consist of an elastomeric or polymeric material.

Preferred materials for the wiper with its wiper lip are, for example, thermoplastic elastomers (for example TPE, TPU, TPV),

Elastomers (for example NBR, FKM, EPDM, HNBR) or combinations of different materials (for example TPU / TPE, PA / TPV).

Preferred materials for the sealing ring with its sealing lip are, for example, thermoplastic elastomers (for example TPE, TPU, TPV) or elastomers (for example NBR, FKM, EPDM, HNBR).

If the wiper and the sealing ring are integral with one another and of the same material, TPU is preferably used for fluid power applications, for example. TPU is a material that is particularly well suited for its wear resistance, media resistance and rigidity. For higher temperature applications, TPV, HNBR or FKM may be considered as these materials have high temperature resistance and good flexibility. Moreover, the invention relates to a scraper and / or sealing ring for an arrangement, as described above, wherein the receptacle of the scraper and / or sealing ring is formed by a substantially U-shaped groove, wherein the receptacle on a congruent designed, substantially in the radial direction extending projection of the second or first machine element in the radial direction floating back and forth and axially sealing can be applied to the projection. A

Overuse of the material from which the scraper and / or the sealing ring is made, is excluded, as well as undesirable large deformations that could adversely affect the performance characteristics of the scraper and / or seal. The scraper and / or the sealing ring always have consistently good service properties during a long service life, especially when the two machine elements to be sealed against each other are deflected in the radial direction relative to each other.

Brief description of the drawing

Arrangements according to the invention are described in more detail below with reference to FIGS. 1 to 11.

These show in a schematic representation:

Fig. 1 shows an arrangement according to the prior art, in which the two

against each other to be sealed machine elements in radial

Direction are deflected relative to each other,

Fig. 2 shows the arrangement of Fig. 1, wherein the radial deflection of the two

Machine elements is further increased relative to each other,

3 shows an embodiment of an arrangement according to the invention, wherein the arrangement is used in a hydraulic cylinder and the first machine element is formed by a rod and the second machine element by the lid of a housing,

4 is a detail of FIG. 3 in an enlarged view,

Fig. 5 is a greatly simplified representation of an inventive

Arrangement in which the two machine elements are deflected at maximum relative to one another in the radial direction, 6 shows a combination element with scraper and sealing ring, as shown in FIG. 5, which is accommodated by its receptacle on a projection of the second machine element, FIG.

7 shows the combination element from FIG. 6 as an individual part, FIG.

Fig. 8 is a combination element, similar to in Fig. 7, wherein additionally

Pressure relief grooves are provided on the inner, static sealing edge,

9 shows a scraper according to the invention as a single part,

10 shows a combination element, similar to FIG. 6, but with the receptacle formed by flanks extending parallel to one another, FIG.

11 shows the combination element from FIG. 10.

Embodiment of the invention

In Figs. 1 and 2, an arrangement is shown, as it is known from the prior art.

The first machine element 1 is formed by a translationally reciprocable rod 10 which is enclosed by the second machine element 2, which is designed as a housing 11, on the outer peripheral side with a radial spacing. In the housing 11, a radially in the direction of the rod 10 open installation groove 27 is provided, in which the sealing ring 5 is received. Radial outer peripheral side of the sealing ring 5 is located on the groove bottom of the installation groove 27 statically sealed. In Fig. 1, the rod 10 is deflected relative to the housing 11 in the radial direction to the right.

It can be seen that by this radial deflection of the rod 10, the sealing lip 7 of the sealing ring 5 on the right side of the representation in the radial direction is charged significantly higher and that the sealing lip 7 in the left part of the representation just the surface to be sealed of the rod 10th adjacent touched. In Fig. 2, the radial deflection of the rod 10 with respect to the housing 11 is further increased.

In the right part of the illustration, the sealing lip 7 of the sealing ring 5 is even more compressed. The overlap, which has the sealing lip 7 of the sealing ring 5 to be sealed surface of the rod 10, is no longer sufficient that the sealing lip 7, the sealed surface of the rod 10 in the circumferential direction fully fitting and thus sealingly. In the left part of the illustration it can be seen that the large radial deflection of the two

Machine elements 1, 2 relative to each other results in a gap through which the medium to be sealed from the space 28 to be sealed in the direction

Environment 29 escapes.

Both the undesirably high mechanical loads on the lip 7 of the sealing ring 5 are to be prevented by the arrangement according to the invention, as well as an undesirable leakage.

In Fig. 3, an embodiment of an inventive arrangement is shown as a whole. A detail of the invention is shown in Fig. 4 enlarged. In Fig. 3, the arrangement comprises the first machine element 1, which is designed as a rod 10 of a hydraulic cylinder, wherein the rod 10 is radially outer peripheral side of the second machine element 2, which is formed by the housing 11 of the hydraulic cylinder enclosed. Of the

Hydraulic cylinder 13 is frontally closed on the one hand by the cover 12, in which the scraper 4 is arranged.

In Fig. 4, the wiper lip 6 of the scraper 4 is shown, which is arranged in the gap 3 between the two machine elements 1, 2. The

Scraper lip 6 sealingly encloses the sealed surface of the rod 10 under radial bias to strip contaminants from the surface of the rod 10, such as dirt particles, water or ice, upon retraction of the rod 10 into the hydraulic cylinder.

In Fig. 5, the principle of the inventive arrangement is shown.

The scraper 4 and the sealing ring 5 are in the combi-element 30th

summarized, thereby forming a pre-assembled unit. The scraper 4 surrounds the rod 10 with the wiper lip 6. As already described above, for example, dirt particles, water or ice are stripped off during retraction of the rod 10 into the hydraulic cylinder 13. On the wiper lip 6 axially opposite side of the combi-element 30 is the

Sealing ring 5 is arranged with its sealing lip 7, which also surrounds the surface of the rod 10 sealingly and prevents sealed medium escapes from the space 28 to be sealed in the interior of the hydraulic cylinder 13 in the environment 29.

The scraper 4 and the sealing ring 5 are taken together by the common receptacle 8 axially sealing and floating in the radial direction 9 on the second machine element 2. The second machine element 2 is in embodiment shown here, the cover 12 of the hydraulic cylinder 13, wherein the lid 12 forms a part of the housing 11.

The receptacle 8 is formed by a substantially U-shaped groove 16 and disposed on the extending in the radial direction 9 projection 17 axially sealing and floating in the radial direction 9.

In Fig. 5, the rod 10, relative to the housing 11, deflected in the radial direction downwards. By floating on the projection 17th

taken shot 8 follows the combination element 30, consisting of the scraper 4 and the sealing ring 5, the relative deflection movement of the two machine elements 1, 2 relative to each other and is therefore corresponding to the rod 10 eccentrically, based on the second machine element 2, respectively. By the floating receiving the wiper lip 6 of the scraper 4 and the sealing lip 7 of the sealing ring 5 are circumferentially in

Essentially consonant burdened; undesirably high and / or different deformations in the circumferential direction on the wiper lip 6 and / or sealing lip 7 are caused by the floating in the radial direction

Recording of scraper 4 and / or sealing ring 5 within the gap 3 avoided.

The receptacle 8 has in all embodiments shown here a maximum radial adjustment path 14, which is at least as large as the maximum radial deflection 15 of the two machine elements 1, 2 relative to each other.

In Fig. 6, an embodiment is shown, which corresponds to the embodiment of FIG. 5. The end faces 21, 22 of the groove 16 are formed relatively conical to each other. The groove base 23 of the groove 16 has an extension 24 in the axial direction 25, which is smaller than the distance 26, the limit the sealing edges 19, 20 in the axial direction. The conical groove 16 allows better manufacturability, and by the cone of the scraper during the intended use always independently on the second machine element 2, here on the cover 12, centered.

As in all embodiments shown here, the groove 16 has on its radially open side 18, two static sealing edges 19, 20 which touch the projection 17 axially on both sides in each case under axial bias sealingly.

By the cone described above, a bias of the static sealing edges 19, 20 produced on the projection 17, which has a positive influence on the sealing effect in the area of recording and projection.

In Fig. 7, the combination element 30 of FIG. 6 is shown as a single part.

In Fig. 8, a combination element 30 is shown, which substantially corresponds to the combination element 30 of FIG. 7, wherein the axially in the direction of

having sealed space 28 arranged static sealing edge 19 has additional pressure relief grooves. Such a configuration allows a pressure relief between the space 28 to be sealed

arranged sealing ring 5 and the scraper 4, in order to prevent the combination element 30 is pressed out of its installation space due to pressure. Through the pressure relief grooves 31, the medium to be sealed can escape in small quantities. This pressure is reduced and the user gets an indication of the due maintenance without the system collapsing.

In Fig. 9, a scraper 4 or a sealing ring 5 is shown as a single part, with a scraper lip 6 or a sealing lip 7. In contrast to the combi-element 30 of FIG. 6 is here only the scraper 4 or the sealing ring 5 part of the arrangement. FIGS. 10 and 11 show a further embodiment.

In Fig. 10, the combination element comprising the scraper 4 and the sealing ring 5, a receptacle 8, in which the end faces 21, 22 of the groove 16 are arranged in the radial direction substantially parallel to each other. The end faces 21, 22 touch the projection 17 fitting and axially sealing. In Fig. 11, the combination element 30 of FIG. 10 is shown as a single part.

Claims

claims

1. Arrangement comprising a first machine element (1), the

on the outer peripheral side is spaced apart by a second machine element (2), wherein in the gap formed by the gap (3) a scraper (4) is arranged, wherein the scraper (4) at least one scraper lip (6), wherein the scraper lip ( 6) a surface to be sealed of the first (1) or second

Machine element (2) sealingly contacted and wherein the scraper (4) on the second (2) or first machine element (1) is accommodated, characterized in that the scraper (4) comprises a receptacle (8) and axially through the receptacle (8) sealingly and in the radial direction (9) floating on the second (2) or first machine element (1) is received.

2. Arrangement, comprising a first machine element (1), the

on the outer circumference side of a second machine element (2) is enclosed at a distance, wherein in the gap formed by the gap (3) a sealing ring (5) is arranged, wherein the sealing ring (5) has at least one sealing lip (7), wherein the sealing lip ( 7) a surface to be sealed of the first (1) or second

Machine element (2) sealingly contacted and wherein the sealing ring (5) on the second (2) or first machine element (1) is accommodated, characterized in that the sealing ring (5) comprises a receptacle (8) and axially through the receptacle (8) sealingly and in the radial direction (9) floating on the second (2) or first machine element (1) is received.

3. Arrangement, comprising a first machine element (1), the outer peripheral side of a second machine element (2) is spaced apart, wherein in the gap formed by the gap (3) a scraper (4) and a sealing ring (5) are arranged wherein the wiper (4) at least one wiper lip (6) and the sealing ring (5) at least one sealing lip (7), wherein the wiper lip (6) and the sealing lip (7) to be sealed surface of the first (1) or second machine element (2) sealingly touching and being the

Scraper (4) and the sealing ring (5) on the second (2) or first

Machine element (1) are accommodated, characterized in that the scraper (4) and the sealing ring (5) comprise a receptacle (8) and by the receptacle (8) axially sealing and in the radial direction (9) floating on the second (2) or first machine element (1)

are included.

4. Arrangement according to one of claims 1 to 3, characterized in that the first machine element (1) by a rod or shaft (10) is formed and the second machine element (2) by a housing (1 1).

5. Arrangement according to claim 4, characterized in that the

Housing (1) comprises a cover (12) of a hydraulic cylinder (13).

6. Arrangement according to claim 5, characterized in that the

Scraper (4) and / or the sealing ring (5) axially sealing and in the radial direction (9) floating in the lid (12) are added.

7. Arrangement according to one of claims 1 to 6, characterized in that the scraper (4) and the sealing ring (5) are each formed as separately produced items.

8. Arrangement according to one of claims 3 to 6, characterized in that the scraper (4) and the sealing ring (5) are integrally formed merge into one another.

9. Arrangement according to claim 8, characterized in that the

Scraper (4) and the sealing ring (5) are formed of the same material.

10. Arrangement according to one of claims 1 to 9, characterized in that the receptacle (8) is formed integrally with the scraper (4) and / or the sealing ring (5).

11. Arrangement according to one of claims 1 to 10, characterized in that the receptacle (8) has a maximum radial adjustment path (14), the> the maximum radial deflection (15) of the two machine elements (1, 2) relative to each other.

12. Arrangement according to one of claims 1 to 11, characterized in that the receptacle (8) by a substantially U-shaped groove (16) is formed, which has a congruent designed and in the

Essentially in the radial direction (9) extending projection (17) of the second (2) or first machine element (1) axially sealing and in the radial direction (9) enclosing floating.

13. Arrangement according to claim 12, characterized in that the groove (16) on its radially open side (18) has two static sealing edges (19, 20) which touch the projection (17) axially on both sides in each case under axial prestressing sealing.

14. Arrangement according to one of claims 12 or 13, characterized in that the groove (16) end faces (21, 22), of which one is conical with respect to the other, such that the groove bottom (23) of the groove ( 16) has an extension (24) in the axial direction

(25), that the sealing edges (19, 20) have an axial distance (26) from each other and that the extension (24) is smaller than the distance

(26).

15. Arrangement according to one of claims 1 to 14, characterized in that the scraper (4) and / or the sealing ring (5) consist of an elastomeric or polymeric material.

16. scraper and / or sealing ring for an arrangement according to one of

Claims 1 to 15, characterized in that the receptacle (8) of the scraper (4) and / or sealing ring (5) by a substantially U-shaped groove (16) is formed and that the receptacle (8) on a congruent designed, substantially in the radial direction (9) extending projection (17) of the second (2) or first

Machine element (1) floating in the radial direction back and forth and axially sealing to the projection (17) can be applied.