DE102015222749B4 - Sealing arrangement and bearing arrangement with sealing arrangement - Google Patents

Abstract

The present invention relates to a sealing arrangement for sealing a first machine element (02) from a second machine element (03) rotatable about an axis (04) with respect to the first machine element (02), comprising a sealing washer (07) fastened to the first machine element (02). with an elastic sealing body (08) and a first magnetic ring as well as a second disc magnet (11) attached to the second machine element (03) axially spaced from the sealing washer (07). According to the invention, the sealing body (08) is radially sealing via a circumferential sealing lip (12) to the second machine element (03) in contact, wherein the magnetic ring of the elastic sealing body (08) is designed as a first disc magnet (09) fully embedded therein and the second disc magnet (11) has a magnetization in which at least two poles of the magnetization around the Axis (04) are distributed around so that between the two discs Magnets (09, 11) alternately attracting and repelling magnetic forces act in the direction of rotation around the axis (04), by means of which the elastic sealing body (08) can be deflected in the axial direction in such a way that it causes a tumbling movement when the second disc magnet (11) rotates through which the sealing lip (12) has an axially enlarged contact area (18) on the second machine element (03). The invention also relates to a bearing arrangement (01) which is equipped with the sealing arrangement according to the invention.

Description

Field of invention

The present invention initially relates to a sealing arrangement for sealing a first machine element with respect to a second machine element rotatable relative to the first machine element. The invention also relates to a bearing arrangement which is equipped with the sealing arrangement according to the invention.

Background of the invention

A seal between at least two machine elements is used to limit or prevent unwanted material transfers from one room to another. The seal is used to seal against external influences, such as, for example, dirt or splash water, or to maintain lubrication by means of introduced fluid in the interior of a delimited space.

A sealing arrangement with sealing surfaces moving relative to one another represents a tribological system. In rotating shafts with contacting radial seals, high friction occurs at the point on the shaft where the sealing component is in contact, especially at high speeds or through high pressure to maintain the seal. The sealing component is therefore designed according to the prior art in such a way that the frictional heat is kept as low as possible. To achieve this, the sliding sealing surface is made as narrow as possible. Despite narrow sealing surfaces, very high frictional power densities can be generated at high pressure, which can result in the sealing lip burning. For example, with a sealing surface pressure of 3 MPa for a shaft with a diameter of 50 mm at a speed of only 3,000 revolutions / min and a coefficient of friction of f = 0.2, a friction power density of over 540 watts per cubic centimeter results. For this reason, the maximum rotational speeds and the maximum pressures for elastomer seals are limited. Materials with a low coefficient of friction are also used, in which a low friction power density is generated. However, seals made from these materials are more expensive.

Another alternative for reducing frictional heat are radial seals with wave-shaped sealing surfaces, which ensure improved lubrication and cooling in the sealing gap. However, these wave-like structures can wear out very quickly, so that the effect is only temporary. As is known, the frictional heat generated in the sealing gap is largely dissipated via the shaft, since the thermal conductivity of the elastic sealing component is low.

In the DE 20 2010 003 593U1 Block-shaped magnets are shown that are used to seal leaks, for example on metal barrels or tanks.

The DE 10 2010 039 378 A1 teaches a seal that has two sealing devices between at least two components, a barrier fluid being arranged in the space between the two sealing devices. An associated magnet with its magnetic field penetrates at least part of the space. The barrier fluid serves as a carrier fluid for a magnetorheological fluid, the seal at the gap sealing against the fluid flowing through. Magnetically attractable dirt particles are held by the magnet, so that the wear of the sealing devices is reduced.

Through the print GB 1 256 549 A a sealing device for a ship's propeller shaft or another rotating shaft is known which is formed with two sealing rings which are rotatable relative to one another and axially movable. One of the sealing rings is carried by a flexible membrane and has an annular sealing element and a ring of permanent magnets 32 in its end face facing a mating ring, which presses the sealing element sealingly against the mating ring and is arranged radially inside the sealing element. The counter ring is made of magnetizable material and is attached to a sleeve hub in order to rotate with the shaft.

Object of the invention

Proceeding from the solutions of the known prior art, the invention is thus based on the object of providing a sealing arrangement with a radially sealing sealing washer which exhibits little wear even at high contact pressure and / or at high speed. Furthermore, a bearing arrangement with such a sealing arrangement is to be provided.

Description of the invention

According to the invention, the stated object is achieved by a sealing arrangement according to the attached claim 1 and by a bearing arrangement according to the attached independent claim 7

The sealing arrangement according to the invention is used to seal a first Machine element compared to a second machine element. The second machine element can be rotated about an axis relative to the first machine element. The sealing arrangement comprises a radially sealing sealing washer, which is to be attached to the first machine element preferably in a tight and rotationally fixed manner, for example by means of a press fit or with an adhesive bond. The sealing washer has an axis which coincides with the axis of rotation described above, so that the two axes are identical. The sealing disk preferably has an annular basic shape as a flat hollow cylinder. In addition, the sealing washer has an elastic sealing body, which preferably consists of an elastomer. The elastic sealing body preferably forms the outer shape of the sealing washer. The elastic sealing body is designed to come into contact with or almost in contact with the second machine element in a radially sealing manner, for which purpose the elastic sealing body preferably comprises a circumferential sealing lip which is designed to make a sealing contact with the second machine element. The sealing lip can be formed on the inner circumference or on the outer circumference of the circular ring shape of the elastic sealing body or the sealing washer. A first disc magnet is integrated in the elastic sealing body and is at least firmly connected to the elastic sealing body; namely preferably in that it is let into the elastic material of the sealing body. The first disk magnet preferably has an annular basic shape as a flat hollow cylinder. Alternatively, the first disk magnet preferably has a circular basic shape as a flat cylinder.

Furthermore, the sealing arrangement comprises a second disc magnet, which is to be attached to the second machine element in a rotationally fixed manner at an axial distance from the first disc magnet. The second disc magnet preferably has an annular basic shape as a flat hollow cylinder. Alternatively, the second disk magnet preferably has a circular basic shape as a flat cylinder.

The second disc magnet has a magnetization in which at least two poles of the magnetization are distributed around the axis. The magnetization is thus aligned in a direction of rotation around the axis, so that at least some of the magnetic field lines are arranged circumferentially around the axis. The mentioned circumferential direction can also be viewed as running tangential to the axis. The poles of magnetization are spaced from the axis; preferably equally spaced. The axes of the two disc magnets and the axis of rotation coincide, i.e. H. the axes mentioned are identical. The directions already mentioned and the directions mentioned below, d. H. the circumferential or tangential direction, the axial direction and the radial direction are related to the axis of rotation between the two machine elements, this axis also forming the axis of the sealing disc and the two disc magnets.

In order to ensure the mode of operation according to the invention, the second disk magnet must have the magnetization described, wherein the first disk magnet can also have different magnetizations.

According to the invention, there are alternating attractive and repulsive magnetic forces between the two disc magnets in the direction of rotation around the axis. These magnetic forces deform the elastic seal body. When rotating between the two machine elements, there is also rotation between the two disc magnets, whereby the given alternating attractive and repulsive magnetic forces also rotate. Accordingly, the deformation of the elastic seal body also rotates.

The given alternating attractive and repulsive magnetic forces cause in particular a deflection of the elastic sealing body in the area where it rests against the second machine element and forms a sealing gap. In this area, the elastic sealing body preferably has the sealing lip described. The deflection of the elastic sealing body in the described area takes place in the axial direction. This deflection is undulating in the direction of rotation. The wave-shaped deflection rotates together with the second disc magnet. The wave-shaped deflection leads to the fact that the contact surface of the elastic sealing body on the second machine element is enlarged, whereby the heat dissipation into the second machine element is increased. When it rotates, the sealing body exhibits a wobbling movement, particularly in the area of its sealing lip. The sealing gap, like the sealing lip, is deflected in an undulating manner, so that, in contrast to the prior art, it does not remain stationary.

The frequency and therefore also the speed of the changing deflection of the elastic sealing body are influenced by the selected magnetization of the disc magnets. A higher number of poles of the magnetization of the second disc magnet leads to more changes in the deflection of the elastic sealing body. The construction of the sealing body is preferably designed in such a way that the sealing gap is kept small even with a maximum deflection in order to ensure the function of the sealing arrangement.

The structure according to the invention improves the heat dissipation into the second machine element, so that a reduction in the temperature load on the elastic sealing body is made possible, which enables the sealing arrangement according to the invention to be used more widely than in the prior art. The sealing arrangement according to the invention can be used at higher speeds. A higher permissible sealing surface pressure can also be permitted, which leads to an improved sealing effect.

An essential advantage of the invention is the expanded area of application of the sealing arrangement according to the invention compared to the prior art, since the improved heat dissipation enables use at higher pressures or higher sealing surface pressures.

Another advantage of the invention is that the alternating deflection of the elastic sealing body ensures an improved supply of a fluid into the area between the sealing body and the second machine element. In particular, a sufficient supply of a lubricant into the sealing gap can thus be ensured.

For the invention it is irrelevant which of the two machine elements is at rest while the other of the two machine elements is rotating, or whether both machine elements are rotating. There only has to be a relative rotation that leads to a relative rotation between the two magnetic disks.

In preferred embodiments, the magnetization of the second disc magnet comprises exactly two of the poles, i. H. a north pole and a south pole, so that the magnetization of the second disc magnet is formed diametrically. The two poles are on either side of the axis. A straight line for connecting the two poles preferably intersects the axis. This diametrical magnetization can be viewed as a special case of circumferential magnetization, since the two poles are distributed circumferentially around the axis.

In further preferred embodiments, the magnetization of the second disc magnet comprises more than two of the poles, which are arranged distributed around the axis, so that the magnetization of the second disc magnet is multipolar. The more than two poles are preferably evenly distributed around the axis. The magnetization described is designed to run around the axis.

The first disk magnet preferably has a magnetization aligned in the direction of the axis with exactly two poles. A straight line connecting the two poles lies in the axis or at least parallel to the axis. The two poles are preferably formed on the two side surfaces of the first disc magnet.

Alternatively, the first disk magnet also preferably has a magnetization in which at least two poles of the magnetization are distributed around the axis. Accordingly, the first disk magnet can also be magnetized circumferentially, in particular diametrically or multipolar.

In preferred embodiments of the invention, a reinforcement extending around the axis is integrated in the elastic sealing body. The reinforcement is used to mechanically reinforce the sealing body, in particular for a secure fit on or in the first machine element. The reinforcement preferably has an L-shaped cross section. The reinforcement preferably consists of a metal.

The first disc magnet is preferably completely embedded in the elastomer of the sealing body, so that it is completely surrounded by the sealing body.

The first and second disc magnets are preferably formed by permanent magnets. The second disc magnet is preferably rigid. The magnetization of the first disk magnet and the magnetization of the second disk magnet are preferably opposite one another, so that the magnetic forces occurring between the two disk magnets are aligned parallel to the axis.

The sealing arrangement according to the invention can be installed in various bearings, in particular in roller bearings. The sealing arrangement according to the invention can be used, for example, in industry, in particular in the automotive industry, but also in medical technology or in wind power plants. A wide range of uses is given, since the sealing arrangement can be implemented in a wide range of sizes.

The bearing arrangement according to the invention comprises a first machine element and a second machine element rotatable about an axis relative to the first machine element. The bearing arrangement serves to support the first machine element with respect to the second machine element. It further comprises the sealing arrangement according to the invention. The sealing washer is attached to the first machine element in a sealed and rotationally fixed manner. The sealing washer lies radially sealing against the second machine element. The second disc magnet is non-rotatable and axially spaced attached to the sealing washer on the second machine element.

The bearing arrangement preferably comprises a preferred embodiment of the sealing arrangement according to the invention. The bearing arrangement preferably also has features that are described in connection with the sealing arrangement according to the invention.

The first machine element is preferably formed by a housing. The second machine element is preferably formed by a shaft. The sealing washer is preferably firmly seated in an opening in the housing. The opening preferably has a circular cross section. The shaft is passed through the opening.

Of course, the second machine element can also be formed by a housing, while the first machine element is formed by a shaft.

Figure list

• 1 eine perspektivische Teilansicht einer bevorzugten Ausführungsform einer erfindungsgemäßen Lageranordnung; und
• 2 eine perspektivische Schnittansicht einer weiteren bevorzugten Ausführungsform der erfindungsgemäßen Lageranordnung.

Further advantages and details of the present invention emerge from the following description of preferred embodiments with reference to the accompanying drawings. Show:

• 1 a perspective partial view of a preferred embodiment of a bearing arrangement according to the invention; and
• 2 a perspective sectional view of a further preferred embodiment of the bearing arrangement according to the invention.

Detailed description of the drawings

1 shows a perspective view of a section of a preferred embodiment of a bearing arrangement according to the invention 01 . The bearing arrangement 01 comprises a housing forming a first machine element 02 , in which a shaft forming a second machine element 03 around an axis 04 is rotatably mounted. The axis 04 thus forms the axis of rotation and is also a central axis of symmetry of the shaft 03 .

The bearing arrangement 01 furthermore comprises a circular opening 06 of the housing 02 pressed-in circular sealing washer 07 which the wave 03 seals radially. The sealing washer 07 sits tightly and rotatably in the housing 02 . It comprises an elastic sealing body 08 made of an elastomer, which is the outer shape of the sealing washer 07 certainly.

The sealing washer 07 serves to seal between the shaft 03 and the case 02 and protects an interior of the case 02 from external influences.

In the seal body 08 is a first circular disc magnet 09 embedded. The axis 04 also forms an axis of the first disc magnet 09 . The bearing arrangement also includes 01 one on the wave 03 non-rotating rigid second disc magnet 11 , which is axially spaced from the first disc magnet 09 is arranged. The second disc magnet 11 is circular or annular.

The seal body 08 the sealing washer 07 tapers in a section that is touching the shaft 03 applied in the direction of the axis 04 , creating a contacting sealing lip 12 is trained. Between the sealing lip 12 and the wave 03 becomes a hydrodynamic sealing gap during operation 13 educated.

The first disc magnet 09 has a magnetization that is in the direction of the axis 04 is aligned. This magnetization has exactly two poles, namely a north pole N and a south pole S. A straight line connecting the two poles is parallel to the axis 04 . The two poles are on the two sides of the first disc magnet 09 .

The second disc magnet 11 has a diametrical magnetization. This magnetization has exactly two poles, namely a north pole N and a south pole S, which are opposite with respect to the axis 04 are arranged. The two poles are thus around the axis 04 arranged around.

2 shows a perspective sectional view of a further preferred embodiment of the bearing arrangement according to the invention 01 . This embodiment is initially similar to that in 1 embodiment shown. Deviating from the in 1 The embodiment shown has the sealing washer 07 a reinforcement 16 on. The reinforcement 16 consists of a metal and has an L-shaped cross section. The reinforcement 16 stabilizes the elastic seal body 08 and ensures a tight fit of the sealing washer 07 in the opening 06 of the housing 02 . The elastic seal body 08 has a circumferential recess on both sides 17th on which a material weakening of the seal body 08 represents and thus to an increased mobility of the sealing lip 12 in the direction of the axis 04 leads.

The magnetizations of the first disc magnet 09 and the second disc magnet 11 lead to the flexible sealing body 08 especially in the area of its sealing lip 12 in the direction of the axis 04 is deflected. Because the poles of the second disc magnet 09 around the axis 04 are arranged distributed around, circumferential areas of the sealing lip 12 with different sense of direction in the direction of the axis 04 deflected so that the sealing lip 12 on the wave 03 describes a wavy line that defines a contact area 18th Are defined. Rotates the shaft 03 in the housing 02 , so will the poles of the second disc magnet 11 turned. This means that the deflection of the sealing lip also rotate 12 causing forces, whereby the deflection of the sealing lip 12 according to the rotation of the shaft 03 around the axis in a tangential direction 04 moves around. There is a wobbling movement of the sealing lip 12 whereby the derivation of the in the area of the sealing gap 13 resulting heat in the shaft 03 is made possible according to the invention to an increased extent. This results in a reduction in the thermal load on the elastic material of the sealing body 08 , whereby the invention allows an extended area of application. The bearing arrangement according to the invention can be operated at higher speeds and / or with a higher sealing surface pressure compared to the prior art.

The sealing lip 12 is designed in such a way that even with a maximum deflection of the sealing lip 12 in the direction of the axis 04 the sealing gap 13 is kept low in order to ensure the function of the seal.

List of reference symbols

01

Bearing arrangement

02

casing

03

wave

04

axis

05

-

06

opening

07

Sealing washer

08

Seal body

09

first disc magnet

10

-

11

second disc magnet

12

Sealing lip

13

Sealing gap

14th

-

15th

-

16

Reinforcement

17th

circumferential recess

18th

Contact area

Claims (8)

Sealing arrangement for sealing a first machine element (02) with respect to a second machine element (03) rotatable about an axis (04) relative to the first machine element (02), comprising a sealing washer (07) with an elastic sealing body (08) attached to the first machine element (02) ) and a first magnetic ring as well as a second disk magnet (11) fastened axially spaced from the sealing disk (07) on the second machine element (03), characterized in that the sealing body (08) seals radially to the second machine element (12) via a circumferential sealing lip (12). 03) is in contact, the magnetic ring of the elastic sealing body (08) being designed as a first disc magnet (09) fully embedded in it and the second disc magnet (11) having a magnetization in which at least two poles of the magnetization around the axis (04 ) are distributed around, so that between the two disc magnets (09, 11) in Umlaufrichtun g alternately attractive and repulsive magnetic forces act around the axis (04), by means of which the elastic sealing body (08) can be deflected in the axial direction in such a way that, when the second disc magnet (11) rotates, it executes a tumbling movement through which the sealing lip ( 12) has an axially enlarged contact area (18) on the second machine element (03). Seal arrangement according to Claim 1 , characterized in that the magnetization of the second disc magnet (11) comprises exactly two of the poles, so that the magnetization of the second disc magnet (11) is formed diametrically. Seal arrangement according to Claim 1 , characterized in that the magnetization of the second disc magnet (11) comprises more than two of the poles which are equally distributed around the axis (04) so that the magnetization of the second disc magnet (11) is multipolar. Sealing arrangement according to one of the Claims 1 to 3 , characterized in that the first disk magnet (09) has a magnetization oriented in the direction of the axis (04). Sealing arrangement according to one of the Claims 1 to 3 , characterized in that the first disc magnet (09) has a magnetization in which at least two poles of the magnetization are distributed around the axis (04). Sealing arrangement according to one of the Claims 1 to 5 , characterized in that a reinforcement (16) extending around the axis (04) is integrated in the elastic sealing body (07). Bearing arrangement (01) with a first machine element (02) and with a second machine element (03) rotatable about an axis (04) relative to the first machine element (02), further comprising a sealing arrangement according to one of the Claims 1 to 6th , characterized in that the sealing washer (07) is attached tightly and non-rotatably to the first machine element (02) and rests sealingly on the second machine element (03), the second disc magnet (11) being rotationally fixed and axially spaced from the sealing washer (07) on the second machine element (03) is attached. Bearing arrangement (01) Claim 7 , characterized in that the first machine element (02) is formed by a housing and that the second machine element (03) is formed by a shaft, the sealing washer (07) sitting firmly in an opening (06) in the housing and the shaft through the opening (06) is passed in the housing.

Images