Bearing assembly

Abstract

The invention relates to a bearing assembly, in particular a bearing assembly (1) for a wind turbine, comprising a shaft (3) rotatably mounted in at least one first bearing, the shaft being at least partially immersed in a hydraulic oil sump (6) filled with a hydraulic fluid (5), a hydraulic delivery device (7) being arranged in the hydraulic oil sump, the hydraulic delivery device has a concave, circular, arcuate contour (8) in cross section, which, together with the shaft having a circular cross section, forms a cylindrical, annular hydraulic channel (9) between the contour of the hydraulic delivery device and the shaft rotating in the direction of rotation during operation, the hydraulic channel has a channel inlet (10) located in the direction of rotation of the rotating shaft and a channel outlet (11) located downstream of the channel inlet in the direction of rotation, and a pressure channel (12) is formed between the channel inlet and the channel outlet, which pressure channel extends from the contour and through the hydraulic delivery device, the pressure channel is arranged such that during operation of the bearing arrangement, hydraulic fluid can be conveyed out of the hydraulic oil sump via the pressure channel.

Description

Technical Field

[0001] The invention relates to a bearing assembly, in particular for a wind turbine, comprising a shaft rotatably mounted in at least one first bearing, wherein the shaft is at least partially immersed in a hydraulic oil sump filled with a hydraulic fluid. Background Art

[0002] Rolling bearings are usually used today for rotor bearings in wind turbines. However, it has already been proposed, for example in DE 102 55 745 A1, to use sliding bearings for such rotors.

[0003] The use of plain bearings in the field of transmission gears for wind turbines is also known in principle, as shown in EP 1 184 567 A2. Another field of application of plain bearings in wind turbines can also be tower slewing ring bearings, which are also known from DE 100 43 936 A1. Furthermore, it is also known to use plain bearings for rotor blade bearings in wind turbines, as is apparent from DE 10 2005 051 912 A1, for example.

[0004] Common to all possible applications of plain bearings within wind turbines is that adequate and secure lubrication is essential for the life and operational reliability of such plain bearings. The oil pressure or volume flow usually required to lubricate the plain bearings is usually provided by an electric pump (e.g. a gear pump). In the event of a power failure, the lubrication and subsequently the plain bearing may fail, which is usually undesirable.

[0005] Hydrodynamic plain bearings are also known in other fields of application than wind power generation; these plain bearings are "self-lubricating" plain bearings that can be operated without an oil pump. Examples of this can be found in US 568756, US 1193471 and DE 19546974 B4. Fixed or loose lubrication rings are usually used, which carry the lubricating oil by wetting, and then scrape the lubricating oil off at another point of the plain bearing. However, due to the low speed of the main rotor of the wind turbine, these methods are difficult or impossible to implement. In addition, these design variants do not allow any significant pressure accumulation, which is usually required when used in a wind turbine. Summary of the invention

[0006] The object of the present invention is therefore to avoid or at least reduce the problems known from the prior art and to provide a bearing assembly, in particular for a wind turbine, which enables particularly safe lubrication of bearing parts which are movable relative to each other independently of the electric pump.

[0007] The object is achieved by a bearing assembly, in particular a bearing assembly for a wind turbine, comprising a shaft rotatably mounted in at least one first bearing, wherein the shaft is at least partially immersed in a hydraulic oil pool filled with a hydraulic fluid, wherein a hydraulic delivery device is arranged in the hydraulic oil pool and has a concave circular arc-shaped profile in cross section, which together with the shaft having a circular cross section forms a cylindrical annular hydraulic channel between the profile of the hydraulic delivery device and the shaft rotating in a rotational direction during operation, wherein the hydraulic channel has a channel inlet located in the rotational direction of the rotating shaft and has a channel outlet located behind the channel inlet in the rotational direction, and a pressure channel is formed between the channel inlet and the channel outlet, which pressure channel starts from the profile and extends through the hydraulic delivery device, so that during operation of the bearing assembly, the hydraulic fluid can be delivered from the hydraulic oil pool via the pressure channel.

[0008] The object of the present invention is also achieved by a bearing assembly, in particular a bearing assembly for a wind turbine, which bearing assembly comprises a shaft rotatably mounted in at least one first bearing, wherein the shaft is at least partially immersed in a hydraulic oil pool filled with a hydraulic fluid, wherein a hydraulic delivery device is arranged in the hydraulic oil pool and has a substantially flat profile, which together with an end face of the shaft having a circular cross section forms a cylindrical annular hydraulic channel between the profile of the hydraulic delivery device and the shaft rotating in a rotational direction during operation, wherein the hydraulic channel has a channel inlet located in the rotational direction of the rotating shaft and has a channel outlet located behind the channel inlet in the rotational direction, and a pressure channel is formed between the channel inlet and the channel outlet, which pressure channel starts from the profile and extends through the hydraulic delivery device, so that during operation of the bearing assembly, the hydraulic fluid can be delivered from the hydraulic oil pool via the pressure channel.

[0009] This has the advantage, inter alia, that reliable oil lubrication can be provided without having to resort to, for example, an electrically driven pump, so that by dispensing with a conventional oil pump, a large number of moving, wear-prone mechanical parts can also be dispensed with.

[0010] Compared to the lubricating oil pumps commonly used today, the hydraulic delivery device of the bearing assembly according to the invention is extremely reliable and virtually wear-free.

[0011] The basic idea of ​​the present invention is to exploit this hydrodynamic pressure build-up effect to pressurize hydraulic fluid; not necessarily to carry loads, but to divert hydraulic fluid, particularly from pressure zones, and use the hydraulic fluid for lubrication inside or outside a bearing assembly.

[0012] In particular, the hydraulic conveying device is thus a component separate from the bearing of the bearing assembly. However, in principle, it is also conceivable to design the hydraulic conveying device, for example, with a plain bearing of the bearing assembly or in a plain bearing of the bearing assembly. The hydraulic conveying device can also be configured as a so-called plain bearing seat.

[0013] The hydraulic fluid delivered by the hydraulic delivery device can be used to lubricate the plain bearings and / or rolling bearings of the bearing assembly.

[0014] The hydraulic delivery device is preferably designed in such a way that the pressure of the pressurized hydraulic fluid in the pressure channel is higher than the pressure of the hydraulic fluid in the hydraulic oil sump.

[0015] In particular, the hydraulic conveying device can also be designed so that it can be operated in a substantially wear-free manner. This means that during operation of the bearing assembly, the rotating shaft is mechanically separated from the hydraulic conveying device by the hydraulic channel.

[0016] The hydraulic delivery device has a pressure channel with a channel inlet which is preferably located in the region of a pressure zone established in the hydraulic channel during operation of the bearing assembly so that hydraulic fluid can be “drained” from the hydraulic channel under pressure and fed into the pressure channel.

[0017] As a result, the hydraulic conveying device itself can no longer participate in the bearing of the shaft or can participate only to a limited extent and can therefore preferably be designed as a separate component of the bearing assembly.

[0018] The first bearing of the bearing assembly according to the invention can be designed as a sliding bearing or as a rolling bearing.

[0019] The hydraulic fluid may in particular be a lubricating oil and / or a cooling oil.

[0020] According to an advantageous embodiment of the invention, it can be provided that the pressure channel is arranged in the region of the channel outlet, which has proven to be particularly advantageous for pressurizing the hydraulic fluid.

[0021] According to another preferred refinement of the invention, it can also be provided that the hydraulic conveying device is mounted in a tiltable manner relative to the shaft, so that during operation of the bearing assembly, the channel inlet can have a larger flow cross section than the channel outlet. This makes it possible to achieve a particularly advantageous pressure build-up in the hydraulic channel.

[0022] Furthermore, according to an equally advantageous embodiment of the invention, it can be provided that the hydraulic delivery device is spring-loaded in the radial direction toward the shaft by means of a spring element, which can also contribute to optimizing the pressure buildup in the hydraulic channel and improving the control of the volume flow of the hydraulic fluid. Alternatively, the hydraulic delivery device can be spring-loaded in the axial direction toward the shaft by means of a spring element.

[0023] According to another particularly preferred embodiment of the invention, it can be provided that the spring element is arranged on the side of the symmetry axis of the profile facing the channel outlet, whereby the volume flow of the hydraulic fluid and the pressurization of the hydraulic fluid can be regulated and controlled even more precisely.

[0024] In addition, the present invention can be further improved so that the hydraulic delivery device has a first groove on its profile, the first groove extends in the axial direction and is hydraulically connected to the pressure channel, which helps to discharge the pressurized hydraulic fluid from the hydraulic channel to the pressure channel in a controlled manner. Alternatively, the hydraulic delivery device can have a first groove on its profile extending in the radial direction, the first groove is hydraulically connected to the pressure channel.

[0025] In a likewise preferred embodiment variant of the invention, it can also be provided that the hydraulic delivery device has a second groove on its contour, which extends tangentially and is hydraulically connected to the first groove, which can also contribute to optimizing the volume flow of the hydraulic fluid to the pressure channel.

[0026] It may also be advantageous to further develop the invention such that the channel inlet and the channel outlet are positioned within the hydraulic oil sump during operation of the bearing assembly, which may contribute to a particularly reliable supply of hydraulic fluid.

[0027] According to another preferred embodiment of the subject matter of the invention, it can be provided that the bearing assembly has a plurality of hydraulic delivery devices, which can also contribute to improving the supply of pressurized hydraulic fluid. In particular, it is preferred that the hydraulic delivery devices are designed to be substantially the same, which has cost advantages due to a high degree of uniformity.

[0028] Finally, the invention can also advantageously be designed such that the first bearing of the bearing assembly is a sliding bearing, wherein the sliding bearing is lubricated by means of a hydraulic fluid pumped from a hydraulic oil sump. In this context, the hydraulic fluid pumped from the hydraulic oil sump is guided above the hydraulic oil sump in the direction of gravity through an inlet opening, in particular directly to the first bearing. The pressurization of the hydraulic fluid is regulated by the hydraulic delivery device in such a way that corresponding height differences and pressure losses occurring in corresponding hydraulic lines are overcome. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The invention is explained in more detail below with reference to the accompanying drawings without limiting the general concept of the invention.

[0030] In the attached picture:

[0031] Figure 1 shows a cross-sectional view of a bearing assembly,

[0032] Figure 2 shows a top view of the hydraulic conveying device,

[0033] Figure 3 shows a longitudinal section through a first embodiment of a hydraulic conveying device,

[0034] Figure 4 shows a longitudinal section through a second embodiment of a hydraulic conveying device,

[0035] Figure 5 shows an axial cross-sectional view of a first bearing assembly,

[0036] Figure 6 shows an axial cross-sectional view of a second bearing assembly,

[0037] Figure 7 A schematic diagram of a wind turbine is shown. DETAILED DESCRIPTION

[0038] Figure 1 A bearing assembly 1 for a wind turbine 2 is shown, which bearing assembly is also shown by way of example in FIG. Figure 7 The bearing assembly 1 comprises a shaft 3 rotatably mounted in at least one first bearing 4 , wherein the shaft 3 is at least partially immersed in a hydraulic oil sump 6 filled with a hydraulic fluid 5 .

[0039] A hydraulic delivery device 7 is arranged in the hydraulic oil pool 6, which has a concave circular segment-shaped profile 8 in cross section, which together with the shaft 3 which is circular in cross section forms a cylindrical annular hydraulic channel 9 between the profile 8 of the hydraulic delivery device 7 and the shaft 3 which rotates in one rotational direction during operation. The hydraulic channel 9 has a channel inlet 10 located in the rotational direction of the rotating shaft 3 and a channel outlet 11 located after the channel inlet 10 in the rotational direction. A pressure channel 12 is formed between the channel inlet 10 and the channel outlet 11, which starts from the profile 8 and extends through the hydraulic delivery device 7, so that during operation of the bearing assembly 1, the hydraulic fluid 5 can be delivered from the hydraulic oil pool 6 via the pressure channel 12. The pressure channel 12 is arranged in the region of the channel outlet 11. The channel inlet 10 and the channel outlet 11 are positioned in the hydraulic oil pool 6 during operation of the bearing assembly 1.

[0040] from Figure 1It can also be clearly seen in the figure that the hydraulic conveying device 7 is mounted in a tiltable manner relative to the shaft 3, so that during operation of the bearing assembly 1, the channel inlet 10 can have a larger flow cross section than the channel outlet 11. This significantly eccentric support of the hydraulic conveying device 7 ensures a higher throughput of the hydraulic fluid 5 through the hydraulic channel 9. This tiltability of the hydraulic conveying device 7 relative to the shaft 3 is achieved by means of a spring element 14, which is connected to the hydraulic conveying device 7 on the one hand and to a component of the bearing assembly 1 that is fixed in place relative to the shaft 3 on the other hand. The hydraulic conveying device 7 is also spring-loaded in the radial direction toward the shaft 3 by means of the spring element 14. In the embodiment shown, the spring element 14 is arranged on the side of the symmetry axis 15 of the profile 8 facing the channel outlet 11, which thus promotes the tiltability.

[0041] The load applied to the hydraulic conveyor 7 by the spring element 14 is much lower than the load applied by a "correctly" mounted plain bearing and corresponds to approximately p 横向 = 1 MPa, which allows a higher lubricating film thickness and thus also a higher volume flow of the hydraulic fluid 5 through the hydraulic channel 9. Figure 3 The longitudinal cross-section is shown in Figure 2 A hydraulic delivery device 7 known in the art.

[0042] Figure 1 It is also shown that the hydraulic delivery device 7 has a first groove 13 extending in the axial direction on its contour 8, which is hydraulically connected to the pressure channel 12. Figure 2 It can also be seen in the figure that the hydraulic conveying device 7 also has two second grooves 16 extending in the tangential direction and in parallel on its profile 8, which are hydraulically connected to the first groove 13. In the embodiment shown, this results in a U-shaped channel structure being formed at the profile 8.

[0043] Figure 5 A first embodiment of a bearing assembly 1 is shown, in which the bearing assembly 1 has two hydraulic delivery devices 7 which are axially spaced apart from one another. The first bearing 4 of the bearing assembly 1 is a plain bearing, wherein the plain bearing is lubricated by means of a hydraulic fluid 5 delivered from a hydraulic oil sump 6 via the hydraulic delivery device 7. The hydraulic fluid 5 delivered from the hydraulic oil sump 6 is guided directly to the first bearing 4 above the hydraulic oil sump 6 in the direction of gravity through an inlet opening 17.

[0044] Figure 6 A second embodiment of a bearing assembly 1 is shown, in which the bearing assembly 1 also has two hydraulic conveying devices 7 axially spaced apart from one another, but wherein the hydraulic conveying devices 7 interact with the shaft 3 in an axial configuration. Figure 6 and Figure 4 Both explain this in more detail.

[0045] The bearing assembly 1 shown comprises a shaft 3 rotatably mounted in at least one first bearing 4, wherein the shaft 3 is at least partially immersed in a hydraulic oil sump 6 filled with a hydraulic fluid 5. In this respect, the basic structure is similar to Figure 5 The configuration shown in is the same.

[0046] In the hydraulic oil sump 6, a hydraulic conveying device 7 is arranged on the left-hand end face, which has a substantially flat contour 8, which together with the left-hand end face of the shaft 3 with a circular cross section forms a hydraulic channel 9 between the contour 8 of the hydraulic conveying device 7 and the shaft 3 rotating in one rotational direction during operation. Although this embodiment has a hydraulic conveying device 7 arranged radially relative to the shaft 3, Figure 6 Also shown is a hydraulic delivery device 7 arranged axially on the left-hand end face of the shaft 3 .

[0047] In the axial configuration shown, the hydraulic channel 9 has a channel inlet 10 located in the rotational direction of the rotating shaft 3 and a channel outlet 11 located behind the channel inlet 10 in the rotational direction, and a pressure channel 12 is formed between the channel inlet 10 and the channel outlet 11, which starts from the contour 8 and extends through the hydraulic delivery device 7, so that during operation of the bearing assembly 1, the hydraulic fluid 5 can be delivered from the hydraulic oil pool 6 via the pressure channel 12.

[0048] The hydraulic delivery device 7 is spring-loaded by means of a spring element 14 in the axial direction toward the shaft 3 and has on its contour 8 a first groove 13 extending in the radial direction which is hydraulically connected to the pressure channel 12 .

[0049] The present invention is not limited to the embodiments shown in the accompanying drawings. Therefore, the above description should not be regarded as limiting, but rather as illustrative. The attached claims should be understood to mean that the stated features exist in at least one embodiment of the present invention. This does not exclude the existence of other features. Where the claims and the above description define a "first" feature and a "second" feature, such naming is used to distinguish between two features of the same type without defining the order of precedence.

[0050] Reference numerals list

[0051] 1 Bearing assembly

[0052] 2. Wind Turbines

[0053] 3 Axis

[0054] 4 Bearings

[0055] 5 Hydraulic fluid

[0056] 6 Hydraulic oil tank

[0057] 7 Hydraulic conveying device

[0058] 8. Outline

[0059] 9 Hydraulic channels

[0060] 10 Channel Entrance

[0061] 11 Channel Exit

[0062] 12 Pressure channels

[0063] 13 Grooves

[0064] 14 Spring element

[0065] 15 Axis of symmetry

[0066] 16 grooves

[0067] 17 Entrance opening

Claims

1. A bearing assembly, in particular a bearing assembly (1) for a wind turbine (2), comprising a shaft (3) rotatably mounted in at least one first bearing (4), the shaft (3) being at least partially immersed in a hydraulic oil sump (6) filled with a hydraulic fluid (5), It is characterized in that A hydraulic delivery device (7) is arranged in the hydraulic oil pool (6), and the hydraulic delivery device has a concave circular arc-shaped profile (8) in cross section, and the profile together with the shaft (3) having a circular cross section forms a cylindrical annular hydraulic channel (9) between the profile (8) of the hydraulic delivery device (7) and the shaft (3) rotating in a rotational direction during operation, wherein the hydraulic channel (9) has a channel inlet (10) located in the rotational direction of the rotating shaft (3) and a channel outlet (11) located after the channel inlet (10) in the rotational direction, and a pressure channel (12) is formed between the channel inlet (10) and the channel outlet (11), the pressure channel starting from the profile (8) and extending through the hydraulic delivery device (7), so that during operation of the bearing assembly (1), the hydraulic fluid (5) can be delivered from the hydraulic oil pool (6) via the pressure channel (12).

2. A bearing assembly, in particular a bearing assembly (1) for a wind turbine (2), comprising a shaft (3) rotatably mounted in at least one first bearing (4), the shaft (3) being at least partially immersed in a hydraulic oil sump (6) filled with a hydraulic fluid (5), It is characterized in that A hydraulic delivery device (7) is arranged in the hydraulic oil pool (6), and the hydraulic delivery device has a substantially flat profile (8), which together with an end face of the shaft (3) having a circular cross section forms a hydraulic channel (9) between the profile (8) of the hydraulic delivery device (7) and the shaft (3) rotating in a rotational direction during operation, wherein the hydraulic channel (9) has a channel inlet (10) located in the rotational direction of the rotating shaft (3) and a channel outlet (11) located after the channel inlet (10) in the rotational direction, and a pressure channel (12) is formed between the channel inlet (10) and the channel outlet (11), the pressure channel starting from the profile (8) and extending through the hydraulic delivery device (7), so that during operation of the bearing assembly (1), the hydraulic fluid (5) can be delivered from the hydraulic oil pool (6) via the pressure channel (12).

3. The bearing assembly (1) according to claim 1 or 2, It is characterized in that The pressure channel (12) is arranged in the region of the channel outlet (11).

4. Bearing assembly (1) according to any one of the preceding claims, It is characterized in that The hydraulic delivery device (7) is mounted in a tiltable manner relative to the shaft (3) so that during operation of the bearing assembly (1), the channel inlet (10) can have a larger flow cross section than the channel outlet (11).

5. Bearing assembly (1) according to any one of the preceding claims, It is characterized in that The hydraulic delivery device (7) is spring-loaded in a radial direction toward the shaft (3) by means of a spring element (14), or the hydraulic delivery device (7) is spring-loaded in an axial direction toward the shaft (3) by means of a spring element (14).

6. The bearing assembly (1) according to claim 4, It is characterized in that The spring element (14) is arranged on the side of the symmetry axis (15) of the contour (8) facing the channel outlet (11).

7. Bearing assembly (1) according to any one of the preceding claims, It is characterized in that The hydraulic conveying device (7) has a first groove (13) extending in the axial direction on the contour (8) of the hydraulic conveying device, and the first groove is hydraulically connected to the pressure channel (12), or the hydraulic conveying device (7) has a first groove (13) extending in the radial direction on the contour (8) of the hydraulic conveying device, and the first groove is hydraulically connected to the pressure channel (12).

8. The bearing assembly (1) according to claim 7, It is characterized in that The hydraulic conveying device (7) has a second groove (16) extending in a tangential direction on a contour (8) of the hydraulic conveying device, the second groove being hydraulically connected to the first groove (13).

9. Bearing assembly (1) according to any one of the preceding claims, It is characterized in that The channel inlet (10) and the channel outlet (11) are positioned within the hydraulic oil sump (6) during operation of the bearing assembly (1).

10. Bearing assembly (1) according to any one of the preceding claims, It is characterized in that The bearing assembly (1) comprises a plurality of the hydraulic delivery devices (7).

11. Bearing assembly (1) according to any one of the preceding claims, It is characterized in that The first bearing (4) of the bearing assembly (1) is a sliding bearing, wherein the sliding bearing is lubricated by means of the hydraulic fluid (5) pumped from the hydraulic oil sump (6).

12. Bearing assembly (1) according to any one of the preceding claims, It is characterized in that The hydraulic fluid (5) delivered from the hydraulic oil sump (6) is guided above the hydraulic oil sump (6) in the direction of gravity through an inlet opening (17) to, in particular directly to, the first bearing (4).

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