Bearing and sealing arrangement of a shaft on a component, especially for a motor vehicle

Abstract

Bearing and sealing arrangement (1) of a shaft (2) on a component (3), in which: - at least one rolling bearing (4) having an inner bearing ring (6) is provided, by means of which the shaft (2) is rotatably mounted on the component (3), - at least one sealing carrier (7) formed separately from the component (3) and separately from the shaft (2) is provided, on which at least one sealing element (8) formed separately from the sealing carrier (7) and separately from the shaft (2) is held for sealing the shaft (2); characterized in that: - the sealing carrier (7) is arranged on the shaft (2) and can be rotated with the shaft (2), which can be sealed against the sealing carrier (7) by means of the sealing element (8); - the inner bearing ring (6) is at least rotationally fixed to the seal carrier (7), so that the shaft (2) can be rotatably mounted on the component (3) by means of the seal carrier (7) and the rolling bearing (4); and - at least one second sealing element (13) is held on the sealing carrier (7), which is formed separately from the sealing carrier (7) and separately from the component (3), by means of which the sealing carrier (7) can be sealed against the component (3).

Description

[0001] The invention relates to a bearing and sealing arrangement of a shaft on a component, in particular for a motor vehicle, according to the preamble of claim 1.

[0002] Such a bearing and sealing arrangement for a shaft on a component designed, for example, as a housing, is already known from DE 36 16 780 A1. In this bearing and sealing arrangement, the shaft is rotatably mounted on the component via at least one rolling bearing, the rolling bearing having an inner bearing ring. Furthermore, the bearing and sealing arrangement includes at least one sealing carrier, designed separately from the component and separately from the shaft, on which at least one sealing element, designed separately from the shaft and separate from the sealing carriers, is held for sealing the shaft.

[0003] Furthermore, EP 1 083 354 B1 discloses a bearing with an integrated seal for a shaft in a housing bore.

[0004] Furthermore, a rolling bearing is known from DE 10 2010 061 932 B3, comprising a first bearing ring and a second bearing ring radially opposite the first bearing ring. The rolling bearing also includes a sealing element with a radially circumferential sealing carrier made of a rigid, inflexible material, which is positively attached to an axial end face of the first bearing ring and extends radially for a predetermined distance towards the second bearing ring.

[0005] Furthermore, EP 2 595 767 B1 discloses a sealing arrangement for use between a housing and a rotatable shaft.

[0006] The object of the present invention is to further develop a bearing and sealing arrangement of the type mentioned above in such a way that a particularly advantageous bearing and sealing of the shaft can be achieved, especially at high rotational speeds of the shaft.

[0007] This problem is solved according to the invention by a bearing and sealing arrangement with the features of claim 1. Advantageous embodiments of the invention are the subject of the dependent claims.

[0008] In the bearing and sealing arrangement according to the invention, for a shaft on a component designed, for example, as a housing, particularly for a motor vehicle, preferably a passenger car, at least one rolling bearing is provided by which the shaft is rotatably mounted on the component, such that the shaft is rotatable about an axis of rotation relative to the component. The shaft can thus rotate about the axis of rotation relative to the component at a speed, the speed of which, for example, can assume different values, particularly in revolutions per minute, during operation of the bearing and sealing arrangement, especially in a normal operating range. The rolling bearing has an inner bearing ring.

[0009] In the bearing and sealing arrangement, at least one sealing carrier, designed separately from the component and the shaft, is provided, on which at least one sealing element, designed separately from the sealing carrier, the shaft, and the component, and made of rubber, for example, is held for sealing the shaft. The sealing element is, for example, a sealing ring, in particular a radial shaft seal.

[0010] To achieve a particularly advantageous bearing and sealing of the shaft, especially at high rotational speeds, the invention provides that the sealing carrier is arranged on the shaft and can rotate with it. This means, for example, that the sealing carrier can be rotationally fixed to the shaft at least within one operating range of the bearing and sealing arrangement. In other words, the sealing carrier is rotationally fixed to the shaft and can rotate with the shaft, particularly about the axis of rotation relative to the component, at least when the shaft speed is within at least one speed range. Specifically, the sealing carrier can be rotationally fixed to the shaft when the shaft speed falls below or reaches a predefined threshold value.The shaft can be sealed against the sealing carrier by means of the sealing element, or is sealed in the first place. In other words, the sealing element is designed to seal the shaft against the sealing carrier.

[0011] Furthermore, according to the invention, the inner bearing ring is at least rotationally fixed to the seal carrier, so that the shaft is rotatably mounted on the component via the seal carrier and the rolling bearing. In particular, the shaft can be supported in its radial direction outwards via the seal carrier on the inner bearing ring and thus on the rolling bearing, and via the rolling bearing on the component, and is thus rotatably mounted. For example, the shaft is rotatably mounted on the component via the rolling bearing at least or exclusively when the rotational speed of the shaft falls below the threshold value.

[0012] Furthermore, according to the invention, at least one second sealing element, formed separately from the sealing carrier and separately from the component, is held on the sealing carrier, by means of which the sealing carrier can be sealed against the component. It has been found that the bearing and sealing arrangement according to the invention allows for a particularly advantageous bearing and sealing of the shaft on the component, so that, especially at very high shaft rotational speeds, unwanted leakage or passage of, for example, oil-based lubricant between the shaft and the component is prevented.As a result, it is possible to design and operate the shaft as a so-called high-speed shaft, so that the shaft can rotate at very high speeds relative to the component without an excessive amount of lubricant flowing between the shaft and the component, which may be designed as a housing, for example.

[0013] The bearing and sealing arrangement according to the invention is therefore particularly advantageous for use in applications involving high shaft rotational speeds or high rotational speeds relative to the component about the axis of rotation. Thus, the bearing and sealing arrangement according to the invention can be particularly advantageously used in an electric machine which, for example, comprises a stator and a rotor rotatable relative to the stator. In this case, for example, the shaft is part of the rotor, so that the shaft, and thus the rotor, can rotate at particularly high speeds relative to the stator without an excessive amount of lubricant flowing between the shaft and the component.In particular, the bearing and sealing arrangement according to the invention makes it possible to combine the advantages of a rolling bearing with those of a sliding bearing without having to accept their respective disadvantages. In this way, for example, it is possible to support and seal the high-speed shaft exclusively using standard components, so that the bearing and sealing arrangement can be implemented particularly cost-effectively even when the shaft rotates at very high speeds around the axis of rotation relative to the component in the aforementioned normal operating range of the bearing and sealing arrangement.The term "normal operating range" means, in particular, that the bearing and sealing arrangement is designed for the normal operating range, so that the preceding and following statements apply specifically to this normal operating range and not to extreme ranges for which the bearing and sealing arrangement is not designed or in which undesirable damage such as overheating and / or insufficient lubrication of the bearing and sealing arrangement occurs.

[0014] In a particularly advantageous embodiment of the invention, the sealing carrier lifts off the shaft in the normal operating range when the shaft's rotational speed exceeds the aforementioned threshold value, which preferably lies within the normal operating range. This lifting of the sealing carrier from the shaft results in a relative rotation between the shaft and the sealing carrier. In other words, if the shaft rotates about its axis of rotation relative to the component so rapidly that its rotational speed exceeds the threshold value, the sealing carrier lifts off the shaft in the radial direction outwards. Consequently, as the shaft continues to rotate, it rotates relative to the sealing carrier, or a relative rotation occurs between the shaft and the sealing carrier.The lifting of the seal carrier from the shaft results primarily from centrifugal forces acting on the seal carrier, particularly those directed radially outwards along the shaft. These forces arise from the rotation of the shaft, and consequently the seal carrier, around its axis of rotation. In other words, before lifting off the shaft, the seal carrier is fixed to the shaft, so that the shaft and the seal carrier rotate at the same speed around the axis of rotation relative to the component. This results in the aforementioned centrifugal forces acting on the seal carrier, directed radially outwards along the shaft. As the rotational speed of the shaft and the seal carrier increases, so do the centrifugal forces acting on the seal carrier.If the rotational speed of the shaft, and thus of the seal carrier, exceeds the threshold value, the centrifugal forces, for example, exceed a limit value, resulting in the seal carrier lifting off the shaft. Consequently, the shaft rotates relative to the seal carrier. Since the threshold value and the rotational speed exceeding the threshold value are within the normal operating range, the lifting of the seal carrier from the shaft occurs intentionally. In other words, the lifting of the seal carrier from the shaft is a desired and deliberately designed event that occurs intentionally within the normal operating range when the shaft rotational speed exceeds the threshold value.By allowing this targeted or desired lifting, such conditions can be created in a particularly simple way, so that the advantages of a rolling bearing can be combined with the advantages of a sliding bearing in the bearing and sealing arrangement according to the invention.

[0015] The aforementioned threshold can be set or specified, for example, by appropriately selecting or designing the coupling or connection between the sealing carrier and the shaft. In other words, since the sealing carrier is rotatable with the shaft and, for example, is rotationally fixed to the shaft, particularly when the rotational speed falls below or reaches the threshold, a coupling or connection, especially a rotationally fixed coupling or connection, between the sealing carrier and the shaft is provided, at least when the rotational speed falls below the threshold. This rotationally fixed coupling or connection of the sealing carrier to the shaft is provided, in particular, when the shaft's rotational speed is zero, that is, when the shaft is at rest relative to the component.The rotationally fixed connection or coupling of the seal carrier to the shaft is achieved, for example, by an interference fit of the seal carrier onto the shaft, i.e., by a press fit of the seal carrier to the shaft. This means, for example, that when the shaft rotational speed falls below or reaches a certain threshold, the seal carrier is connected to the shaft by means of the aforementioned interference fit or press fit. For this purpose, an interference fit of the seal carrier onto the shaft is provided. The interference fit can be designed in a simple manner such that it weakens or decreases with increasing rotational speed and thus with increasing centrifugal forces acting on the seal carrier.If the rotational speed of the shaft exceeds the threshold value, the press fit decreases to zero or the press fit is eliminated, so that the seal carrier lifts off the shaft and the shaft subsequently rotates relative to the seal carrier.

[0016] In a particularly advantageous embodiment of the invention, the lifting process results in at least one gap into which the lubricant, which is designed in particular as a liquid and for example as oil, flows, so that a sliding bearing is created that at least includes the gap and the lubricant, by means of which the shaft is rotatably mounted on the sealing carrier.Because the seal carrier lifts off the shaft, and because the shaft is supported on the component via the rolling bearing mediated by the seal carrier, this lifting action results in, for example, the removal of any rolling bearing provided by the rolling bearing being eliminated. Consequently, the shaft is then rotatably mounted on the component around its axis of rotation relative to the component solely by means of the sliding bearing, or alternatively, the lifting of the seal carrier from the shaft results in the shaft being rotatably mounted on the component via both the sliding and rolling bearings. This allows the advantages of rolling and sliding bearings to be combined without incurring their disadvantages, or at least without their drawbacks.

[0017] The invention is based in particular on the understanding that, for example, in conventional applications such as internal combustion engines, rotating shafts are supported by plain bearings or, especially in gearboxes, by rolling bearings. Radial shaft seals are typically used to seal the respective shaft against, for example, a housing, in order to prevent, for instance, dirt from penetrating the housing from the outside or lubricant from leaking out. The support and sealing of high-speed shafts conventionally requires special and expensive bearings and seals. However, with the bearing and sealing arrangement according to the invention, it is now possible to support and adequately seal the shaft with cost-effective standard parts even when very high shaft speeds occur during normal operation.In particular, excessive loads, excessive wear, and premature failure of the rolling bearing and sealing elements can be avoided, thus preventing leaks. At the same time, the shaft can be mounted on the component with particularly low friction.

[0018] Another embodiment is characterized in that the shaft has at least one guide element by means of which the lubricant, in particular oil, can be guided in the gap. The guide element is, for example, provided or formed on or in an outer circumferential surface of the shaft. By means of the guide element, the lubricant can be directed into the resulting gap, thus enabling a particularly advantageous and, in particular, low-friction sliding bearing. Furthermore, a sufficient supply of lubricant to the sliding bearing can be ensured. It has also proven particularly advantageous if the guide element has at least one groove, in particular a spiral groove.This allows the gap to be supplied with a particularly advantageous amount of lubricant, resulting in a particularly advantageous and especially low-friction sliding bearing.

[0019] The second sealing element is designed, for example, as a sealing ring, in particular as a radial shaft seal, which allows for a particularly effective seal. It has also proven to be particularly advantageous if the respective sealing element is made of rubber, thereby achieving a superior sealing function.

[0020] In a further particularly advantageous embodiment of the invention, it is provided that the first sealing element seals the seal carrier against the shaft, at least or preferably only after lifting, in order to prevent an undesired flow of lubricating oil. For example, it can be provided that, before lifting, the sealing of the seal carrier against the shaft by the first sealing element is omitted, since a relative rotation between the shaft and the seal carrier, and thus a relative rotation between the shaft and the first sealing element, does not occur before lifting. Both before and after lifting, the first sealing element can, for example, be supported on the shaft, whereby a sealing effect or sealing function provided by the first sealing element is only established upon a relative rotation between the first sealing element and the shaft.Thus, although the first sealing element can be supported on the shaft both before and after lifting, since, for example, a relative rotation between the shaft and the first sealing element only occurs after lifting, and the sealing function of the first sealing element only occurs with such a relative rotation between the shaft and the first sealing element, sealing of the seal carrier against the shaft by means of the first sealing element only takes place after lifting and thus only with a resulting relative rotation between the shaft and the first sealing element.

[0021] Furthermore, it has proven particularly advantageous if the second sealing element seals the seal carrier against the component both before and after lifting. The preceding and following explanations regarding the first sealing element can also be applied to the second sealing element, such that, for example, the second sealing element only provides its sealing function for sealing the seal carrier against the component when there is a relative rotation between the seal carrier and the component.Since, for example, the seal carrier and thus the second sealing element rotate with the shaft relative to the component before lifting, a relative rotation occurs between the seal carrier and the component, and thus between the second sealing element and the component, before lifting. This means that the second sealing element already provides its sealing effect, or its sealing function, to seal the seal carrier against the component before lifting. The second sealing element is supported on the component both before and after lifting. For example, a relative rotation also occurs between the seal carrier and the component after lifting, and thus between the second sealing element and the component, so that the second sealing element continues to provide its sealing function, i.e., to seal the seal carrier against the component, even after lifting.Overall, it is evident that after lifting, both sealing elements provide their sealing function, ensuring advantageous sealing even at very high shaft speeds.

[0022] The respective sealing element is preferably connected to the sealing carrier in a rotationally fixed manner, so that the respective sealing element rotates, or can rotate, with the sealing carrier relative to the component or the shaft. For example, it is conceivable that the respective sealing element is vulcanized onto the sealing carrier. The respective sealing element has, for example, at least one sealing lip, which can be supported, or is supported, on the shaft or the component. If, for example, a relative rotation occurs between the shaft and the sealing carrier, and thus between the shaft and the first sealing element, the sealing lip of the first sealing element slides or runs along the shaft, in particular along its outer circumferential surface, so that the first sealing element seals the sealing carrier against the shaft.If a relative rotation occurs between the sealing carrier and the component, and thus a relative rotation occurs between the second sealing element and the component, the sealing lip of the second sealing element, for example, slides or runs along a surface of the component, particularly on the inner circumference, so that the second sealing element seals the sealing carrier against the component.

[0023] It has proven particularly advantageous if, as a result of lifting, the seal carrier comes into contact with the component, especially with the component's inner circumferential surface, so that the contact between the component and the seal carrier slows the seal carrier and, via the seal carrier, the inner bearing ring with respect to rotation relative to the component. This prevents, for example, excessive relative rotation between the second sealing element and the component, thus avoiding excessive heat density and consequently excessive wear.

[0024] As already indicated, in an advantageous embodiment of the invention, the threshold value lies below the limiting speed of the rolling bearing and within the normal operating range of the bearing and sealing arrangement, which is designed for this normal operating range. The limiting speed of the rolling bearing is understood to be the speed at which the bearing and sealing arrangement, and thus the rolling bearing, leave the normal operating range, resulting in excessive stress and, in particular, excessive friction and excessive heating of the rolling bearing. In this embodiment, the threshold value, and thus the lifting of the bearing, is therefore located within the normal operating range, so that the lifting of the sealing carrier is a desired effect, specifically achieved or permitted through the appropriate design of the bearing and sealing arrangement.

[0025] Finally, it has proven particularly advantageous if the seal carrier has a clearance fit relative to the component, at least before removal. In other words, a clearance fit between the seal carrier and the component is established, at least before removal. This ensures, for example, that the seal carrier can rotate with the shaft relative to the component before removal without excessive friction.At the same time, adequate sealing can be ensured, and by adjusting the clearance fit, a distance is provided, particularly in the radial direction of the shaft, between the sealing carrier and the component, which is sufficiently large to allow relative rotation between the sealing carrier and the component, but at the same time sufficiently small so that, for example, the sealing carrier comes into contact with the component as a result of lifting off, which can then brake the sealing carrier.

[0026] Further details of the invention will become apparent from the following description of a preferred embodiment with the accompanying drawing. The single figure shows a schematic and cutaway side view of a bearing and sealing arrangement according to the invention for a shaft on a component, in particular for a motor vehicle.

[0027] The single figure shows, in a schematic and cutaway side view, a bearing and sealing arrangement 1 of a shaft 2 on a component 3, which is designed, for example, as a housing. The shaft 2 and the component 3, and thus the bearing and sealing arrangement 1 as a whole, are, for example, components of a motor vehicle's drivetrain, in particular a motor vehicle designed, for example, as a passenger car. The motor vehicle can be driven, for example, by means of the drivetrain. For this purpose, the drivetrain comprises at least one drive unit, designed, for example, as an internal combustion engine or as an electric motor, by means of which the motor vehicle can be driven. The drive unit can include a transmission, which, for example, comprises the shaft 2 and the component 3 as a transmission housing.

[0028] In the bearing and sealing arrangement 1, the shaft 2 is rotatably mounted on the component 3 via at least one rolling bearing 4, such that the shaft 2 can rotate about an axis of rotation 5 relative to the component 3 at a given speed. The rolling bearing 4 thus provides a rolling bearing for the rotatable mounting of the shaft 2. During operation of the vehicle, the speed at which the shaft 2 rotates about the axis of rotation 5 relative to the component 3 can change, or the speed can assume different values. In particular, the speed can be zero or significantly higher than zero. If the speed of the shaft 2 is zero, the shaft 2 does not rotate about the axis of rotation 5 relative to the component 3, but is then at rest.

[0029] The rolling bearing 4 comprises an inner bearing ring 6 and a corresponding outer bearing ring 20. The outer bearing ring 20 can be formed integrally with the component 3. In the embodiment illustrated in the figure, however, the outer bearing ring 20 is a component formed separately from the component 3, wherein the outer bearing ring 20 is fixed to the component 3, for example, in the axial direction of the shaft 2, in the radial direction of the shaft 2, and in its circumferential direction. The outer bearing ring 20 is also referred to as the outer bearing ring and is, for example, pressed into the component 3, that is, connected to the component 3 via a press fit or a press-fit connection. Thus, the outer bearing ring 20 is connected to the component 3 at least in a rotationally fixed manner, so that relative rotations about the axis of rotation 5 between the outer bearing ring 20 and the component 3 are prevented.

[0030] Furthermore, the bearing and sealing arrangement 1 comprises at least one sealing carrier 7, which is formed separately from the component 3 and separately from the shaft 2 and which may, for example, be formed integrally with the inner bearing ring 6. In the embodiment illustrated in the figure, however, the sealing carrier 7 is formed as a component formed separately from the inner bearing ring 6. A sealing element in the form of a first radial shaft seal 8, which is formed separately from the sealing carrier 7, the shaft 2, and the component 3, is held on the sealing carrier 7 for sealing the shaft 2. The radial shaft seal 8 is connected to the sealing carrier 7 in a rotationally fixed manner, so that relative rotations about the axis of rotation 5 between the sealing carrier 7 and the radial shaft seal 8 are avoided.Furthermore, the radial shaft seal 8 is fixed to the seal carrier 7 in the radial and axial directions.

[0031] To achieve a particularly advantageous seal between shaft 2 and component 3, even at high rotational speeds of shaft 2, the seal carrier 7 is arranged on shaft 2 and is rotatable with shaft 2 about the axis of rotation 5 relative to component 3. The inner bearing ring 6, which is formed separately from the seal carrier 7, is at least rotationally fixed to the seal carrier 7, so that shaft 2 is coupled, or can be coupled, to the inner bearing ring 6 (also referred to as the inner bearing ring) via the seal carrier 7. Thus, shaft 2 is rotatably mounted, or is mounted, on component 3, particularly in the radial direction, via the seal carrier 7 and the rolling bearing 4. The inner bearing ring 6 is fixed to the seal carrier 7 in both the radial and axial directions.Furthermore, the inner bearing ring 6 is rotationally fixed to the seal carrier, thus preventing relative rotations between the inner bearing ring 6 and the seal carrier 7 about the axis of rotation 5. For example, the inner bearing ring 6 is pressed into the seal carrier 7 or connected to the seal carrier 7 via a press fit or a press-fit connection.

[0032] The rolling bearing 4 comprises a plurality of rolling elements 9. In the embodiment illustrated in the figure, for example, the rolling elements 9 are designed as balls, so that the rolling bearing 4 can be configured as a ball bearing. Of course, it is also conceivable that the rolling bearing 4 is configured as a different type of rolling bearing, such as a tapered roller bearing or the like. The bearing rings (inner ring 6 and outer ring 20) form, for example, respective raceways 10 for the rolling elements 9. If a relative rotation occurs between the bearing rings about the axis of rotation 5, the rolling elements 9 roll on the raceways 10 and thus on the bearing rings, enabling a particularly low-friction bearing arrangement of the shaft 2 on the component 3, especially in the radial direction.

[0033] For example, when shaft 2 is stationary, and especially when shaft 2 or its rotational speed falls below a threshold value greater than zero (which will be explained in more detail below), the sealing carrier 7 is connected to shaft 2 over a length L of shaft 2 by means of an interference fit or press fit, and is thus rotationally fixed to shaft 2. Furthermore, the sealing carrier 7 is then fixed to shaft 2 in both the radial and axial directions. During the manufacture of the bearing and sealing assembly 1, the sealing carrier 7 is thus, for example, press-fitted onto shaft 2 over the length L. As a result, the sealing carrier 7 rotates at the same speed as shaft 2 about the axis of rotation 5 relative to the component 3 when the rotational speed falls below, or potentially reaches, the threshold value.The inner bearing ring 6 is pressed onto the seal carrier 7, for example, with the outer bearing ring 20 being pressed into the component 3, which is designed in particular as a gearbox housing.

[0034] The seal carrier 7 is designed to accommodate and hold the radial shaft seal 8. This allows the shaft 2 to be sealed against the seal carrier 7 by means of the radial shaft seal 8. In particular, the radial shaft seal 8 seals the shaft 2 against the seal carrier 7 when the rotational speed of the shaft 2 exceeds the threshold value. The radial shaft seal 8 has at least one sealing lip 11 which is supported or bears against the shaft 2, in particular against an outer circumferential surface 12 of the shaft 2, especially both when the rotational speed of the shaft 2 falls below the threshold value and when the rotational speed reaches and exceeds the threshold value.The radial shaft seal 8, for example, provides its sealing function, or rather its sealing effect, to seal the shaft 2 against the seal carrier 7 when there is a relative rotation about the axis of rotation 5 between the shaft 2 and the seal carrier 7, and thus between the shaft 2 and the radial shaft seal 8. Since the seal carrier 7, and therefore the radial shaft seal 8, are rotationally fixed to the shaft 2 when the rotational speed does not exceed the threshold value, the radial shaft seal 8 does not yet exhibit its sealing effect when the rotational speed does not exceed the threshold value.

[0035] Furthermore, the bearing and sealing arrangement 1 comprises at least a second sealing element in the form of a second radial shaft seal 13, which is formed separately from the seal carrier 7, separately from the shaft 2, and separately from the component 3. The radial shaft seal 13 is connected to the seal carrier 7 in a rotationally fixed manner. Thus, relative rotations about the axis of rotation 5 between the radial shaft seal 13 and the seal carrier 7 are prevented. The seal carrier 7 is sealed against the component 3 by means of the radial shaft seal 13.The radial shaft seal 13 provides its sealing effect or sealing function for sealing the seal carrier 7 against the component 3, in particular, and for example, only, when there is a relative rotation between the component 3 and the seal carrier 7, and thus a relative rotation between the component 3 and the radial shaft seal 13. The radial shaft seal 13 has, for example, at least one sealing lip 14, which is supported, in particular, always or permanently, against the component 3, especially against an inner circumferential surface 15 of the component 3. If a relative rotation occurs between the radial shaft seal 8 and the shaft 2, the sealing lip 11, for example, slides or runs off the outer circumferential surface 12.For example, if a relative rotation occurs between the component 3 and the radial shaft seal 13, the sealing lip 14 slides or runs off the inner circumferential surface 15. In particular, a relative rotation between the radial shaft seal 13 and the component 3 occurs both when the rotational speed of the shaft 2 falls below the threshold value and when the rotational speed reaches and exceeds the threshold value. The preceding and following descriptions of the bearing and sealing arrangement 1 refer entirely to a normal operating range, or to the operation of the bearing and sealing arrangement 1 within a normal operating range for which the bearing and sealing arrangement 1 is designed.Within this normal operating range, there is no excessive stress, excessive heating, or excessive wear of the bearing and sealing arrangement 1, so that effects, events, or occurrences within this normal operating range are desirable. This means that the bearing and sealing arrangement 1 is designed in such a way that events occurring within the normal operating range are intentionally or desired to take place or be permitted.

[0036] As can be seen from the figure, the sealing carrier 7 has a material accumulation 16 which is arranged further outwards in the radial direction of the shaft 2 than the radial shaft seal 8. The material accumulation 16 adjoins, for example, the radial shaft seal 13 in the axial direction of the shaft 2, particularly towards the rolling bearing 4. The material accumulation 16 is a partial region T of the sealing carrier 7 which has a greater wall thickness in partial region T than in at least one further partial region B adjoining partial region T.For example, at least when the rotational speed of the shaft 2 does not exceed the threshold value, a clearance fit S is established between the sealing carrier 7 and the component 3, in particular between the material accumulation 16 and the inner circumferential surface 15, such that the sealing carrier 7, in particular the material accumulation 16, has the aforementioned clearance fit S relative to the component 3, in particular relative to the inner circumferential surface 15.

[0037] Since the sealing carrier 7 rotates with the shaft 2 around the axis of rotation 5 relative to the component 3, at least when the rotational speed does not exceed the threshold value, the rotational speed at which the sealing carrier 7 rotates around the axis of rotation 5 relative to the component 3 increases with increasing rotational speed of the shaft 2. As mentioned previously, the sealing carrier 7 and the shaft 2 rotate at the same rotational speed around the shaft 5 relative to the component 3, particularly when the rotational speed of the shaft 2 does not exceed the threshold value. With increasing rotational speed of the sealing carrier 7, the centrifugal forces acting on the sealing carrier 7 and directed outwards in the radial direction of the shaft 2 also increase. In other words, if the rotational speed of the shaft 2, and thus the rotational speed of the sealing carrier 7, increases while the rotational speed does not exceed the threshold value, the centrifugal force acting on the sealing carrier 7 also increases.In particular, the material accumulation 16 causes a centrifugal force directed radially outwards, which affects the press fit provided in the length region L between the sealing carrier 7 and the shaft 2 in such a way that the press fit between the sealing carrier 7 and the shaft 2 decreases or weakens. However, as long as the rotational speed of the shaft 2 and thus of the sealing carrier 7 does not exceed the threshold value, the press fit between the sealing carrier 7 and the shaft 2 is maintained, so that the sealing carrier 7 rotates with the shaft 2 or is rotationally fixed to the shaft 2.At such a time, or when the rotational speed of shaft 2 does not exceed the threshold, for example, only radial shaft seal 13 seals with respect to radial shaft seals 8 and 13, since radial shaft seal 13 rotates relative to component 3, while radial shaft seal 8 does not rotate relative to shaft 2.

[0038] If the rotational speed of shaft 2 exceeds the threshold value, which is below the limiting speed of the rolling bearing 4, the press fit between the seal carrier 7 and shaft 2, provided in the length range L, is reduced to zero. In other words, the press fit between the seal carrier 7 and shaft 2 is then released, thus eliminating the rotationally fixed connection between the seal carrier 7 and shaft 2. Consequently, a relative rotation occurs about the axis of rotation 5 between shaft 2 and the seal carrier 7, and thus between shaft 2 and the radial shaft seal 8. The press fit between the seal carrier 7 and shaft 2 is released because the seal carrier 7 lifts off shaft 2 in the length range L due to the centrifugal forces acting upon it.As a result, at least in the length range L, a gap D is formed in the radial direction of the shaft 2 between it and the sealing carrier 7. Lubricant, especially in the form of oil, can penetrate into this gap D.

[0039] Preferably, the shaft 2 is designed in at least one area C arranged within the component 3 such that oil can easily enter the resulting gap D. For this purpose, the shaft 2 has, for example, at least one guide element in area C, particularly in the form of a spiral groove, by means of which a sufficient quantity of oil is guided into the resulting gap D. Since the gap D is created and oil enters or is guided into the gap D, a sliding bearing G encompassing the gap D and the oil guided into the gap D is formed. The shaft 2 is supported by this bearing on the sealing carrier 7 and, via the carrier, on the component 3, or at least is supported when the rotational speed exceeds the threshold value.Thus, for example, the rolling bearing of the shaft 2 provided by the rolling bearing 4 is no longer the only bearing provided on the component 3, but the rolling bearing transitions, for example, into the sliding bearing G, so that the shaft 2 is rotatably mounted on the component 3 by means of the rolling bearing provided by the rolling bearing 4 and by means of the sliding bearing G, or exclusively by means of the sliding bearing G.

[0040] Since the seal carrier 7 lifts off the shaft 2, and since the inner bearing ring 6 is rotationally fixed to the seal carrier 7, a relative rotation occurs between the shaft 2 and the inner bearing ring 6 when the rotational speed exceeds the threshold value. Therefore, after the seal carrier 7 lifts off the shaft 2, the rotational speed of the inner bearing ring 6 does not increase, or only increases slightly. Because a relative rotation about the axis of rotation 5 occurs between the shaft 2 and the seal carrier 7, and thus between the shaft 2 and the radial shaft seal 8, the radial shaft seal 8 seals the seal carrier 7 against the shaft 2 when the rotational speed exceeds the threshold value. Since, for example, a relative rotation also occurs between the radial shaft seal 13 and the component 3 during this time, the radial shaft seal 13 also seals against the component 3.This means, for example, that an opening in component 3 is sealed by means of both the radial shaft seal 8 and the radial shaft seal 13, wherein, for example, the shaft 2 passes through this opening in component 3, which is designed, in particular, as a through-hole. This means, in particular, that the shaft 2 penetrates the aforementioned opening. If the rotational speed of the shaft 2 does not exceed the threshold value, the opening is sealed, for example, with respect to the radial shaft seals 8 and 13, only by means of the radial shaft seal 13.

[0041] Since, as a result of the lifting of the seal carrier 7 from the shaft 2, the rotational speed of the seal carrier 7 is lower than that of the shaft 2, no impermissibly high relative rotational speeds and thus no impermissibly high relative velocities occur between the radial shaft seal 8 and the shaft 2 and the radial shaft seal 13 and the component 3, so that excessive overloads and in particular excessive heating of the radial shaft seals 8 and 13 can be avoided.

[0042] In particular, it is conceivable that between the sealing carrier 7 and the building element 3, especially between the material accumulation 16 and the building element 3, such a dimensional concept is provided that the sealing carrier 7, especially the material accumulation 16, comes into contact with the building element 3, especially with the inner circumferential surface 15, as a result of lifting off.

[0043] As a result, the component 3 brakes the seal carrier 7 and, via this, the inner bearing ring 6 against rotation about the axis of rotation 5 relative to the component 3. This reliably prevents, for example, excessively high rotational speeds of the rolling bearing 4.

[0044] Overall, it is evident that the bearing and sealing arrangement 1 provides a particularly advantageous seal even at high rotational speeds of the shaft 2, thus preventing, for example, an undesirable flow of oil from a first area 17, located, for instance, in the component 3, through the opening designated 18 into a second area 19, which is located, for example, in the vicinity of the component 3. This allows the shaft 2 to be designed and operated as a high-speed shaft without excessive oil flow into area 18 and thus into the surrounding environment. Reference symbol list 1. Bearing and sealing arrangement 2nd wave 3 Component 4 rolling bearings 5 axis of rotation 6 inner bearing ring 7 sealing carriers 8 Radial shaft seal 9 rolling elements 10 Career 11 Sealing lip 12 outer circumferential surface 13 Radial shaft seal 14 Sealing lip 15 inner circumferential surface 16. Material accumulation Area 17 18 Opening Area 19 20 outer bearing ring B Sub-area C area D gap G Plain bearing L Length range S Game Pass T sub-area

Claims

[1] Bearing and sealing arrangement (1) of a shaft (2) on a component (3), in which: - at least one rolling bearing (4) having an inner bearing ring (6) is provided, by means of which the shaft (2) is rotatably mounted on the component (3), - at least one sealing carrier (7) designed separately from the component (3) and separately from the shaft (2) is provided, on which at least one sealing element (8) designed separately from the sealing carrier (7) and separately from the shaft (2) is held for sealing the shaft (2); characterized by , that: - the sealing carrier (7) is arranged on the shaft (2) and can be rotated with the shaft (2), which can be sealed against the sealing carrier (7) by means of the sealing element (8); - the inner bearing ring (6) is at least rotationally fixed to the seal carrier (7), so that the shaft (2) can be rotatably mounted on the component (3) by means of the seal carrier (7) and the rolling bearing (4); and - at least one second sealing element (13) is held on the sealing carrier (7), which is formed separately from the sealing carrier (7) and separately from the component (3), by means of which the sealing carrier (7) can be sealed against the component (3). [2] Bearing and sealing arrangement (1) according to claim 1, characterized by , that if the rotational speed of the shaft (2) exceeds a threshold value, the sealing carrier (7) lifts off from the shaft (2), resulting in a relative rotation between the shaft (2) and the sealing carrier (7). [3] Bearing and sealing arrangement (1) according to claim 2, characterized by, that at least a gap (D) results from the lifting, into which a lubricant flows, so that a sliding bearing (G) comprising at least the gap (D) and the lubricant is created, over which the shaft (2) is rotatably mounted on the sealing carrier (7). [4] Bearing and sealing arrangement (1) according to claim 3, characterized by , that the shaft (2) has at least one guiding element by means of which the lubricant can be guided into the gap (D). [5] Bearing and sealing arrangement (1) according to claim 4, characterized by that the guiding element has at least one groove, in particular a spiral groove. [6] Bearing and sealing arrangement (1) according to any one of claims 2 to 5, characterized by , that at least after lifting, the first sealing element (8) seals the sealing carrier (7) against the shaft (2). [7] Bearing and sealing arrangement (1) according to any one of claims 2 to 6, characterized by, that before and after lifting, the second sealing element (13) seals the sealing carrier (7) against the component (3). [8] Bearing and sealing arrangement (1) according to any one of claims 2 to 7, characterized by , that the sealing carrier (7) comes into contact with the component (3) as a result of lifting off, which thereby slows down the sealing carrier (7) and via this the inner bearing ring (6) with respect to a rotation relative to the component (3). [9] Bearing and sealing arrangement (1) according to any one of claims 2 to 8, characterized by , that the threshold value is below the limiting speed of the rolling bearing (4) and within a normal operating range of the bearing and sealing arrangement (1), which is designed for the normal operating range. [10] Bearing and sealing arrangement (1) according to any one of claims 2 to 9, characterized by, that the sealing carrier (7) has a clearance fit (S) relative to the component (3) at least before lifting.

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