DE102010027011A1 - Rotary connection for rotor blade or tower bearing of wind-power plant, has rolling members arranged between inner ring and outer ring so that inner ring and outer ring can be pivoted against each other around common pivotal axis - Google Patents

Abstract

The rotary connection (1) has two sets of rolling members (9) arranged between an inner ring (4) and an outer ring (5) so that the inner ring and the outer ring can be pivoted against each other around a common pivotal axis (2). The rolling members include a two-point ball series with a two-point contact, a three-point ball series with a three-point contact, and a four-point ball series with a four-point contact, where the four-point ball series has a contact angle of between 25 and 45 degrees.

Description

Field of the invention

The invention relates to a rotary joint, in particular for rotor blade or tower bearing for a wind turbine, with an inner ring, with an outer ring and at least one Wälzkörperdoppelreihe, which is arranged rolling between the inner ring and the outer ring, so that inner ring and outer ring about a common pivot axis against each other can be pivoted, wherein the at least one Wälzkörperdoppelreihe is formed as a radial double row or as a Axialdoppelreihe. The invention also relates to a rotor blade or tower bearing for a wind turbine with this rotary joint.

Rotary connections in wind turbines make it possible to pivot a rotor blade or even a generator house together with the rotor in order to be able to optimally adjust it to prevailing wind conditions, for example. After wind turbines often have very large rotors with rotor blade lengths greater than 10 m, the rotary joints must be designed to be resilient. Often these are large bearings with pitch diameters greater than 1 m or even larger than several meters.

The loads acting on the rotary joint are often due to the attacking wind forces and prevailing weight forces a mixture of radial and axial loads, and tilting moments.

For example, the document discloses DE 20 2007 011 577 U1 , which is probably the closest prior art, a rolling bearing assembly in the form of a large rolling bearing with a diameter of 0.5 m or more, which is designed to support a wind power blade. The rolling bearing assembly comprises two concentric with each other and at least partially arranged one inside the other, annular elements for connection to one of two mutually rotatable system parts. In the region of a gap between the annular elements at least two rows of rolling elements are provided. According to the embodiment in the 4 even three rows of rolling elements for radial support in axial projection are arranged overlapping.

Field of the invention

The invention has for its object to propose a new, advantageous variant of a rotary joint, in particular for rotor blade or tower storage for a wind turbine and a corresponding rotor blade or tower storage.

This object is achieved by a rotary joint with the features of claim 1 and by a rotor blade or tower bearing with the features of claim 10. Preferred or advantageous embodiments of the invention will become apparent from the dependent claims, the following description and the accompanying drawings.

According to the invention, a rotary joint is proposed, that is to say a roller bearing arrangement which is intended for pivoting, optionally also formed over 360 degrees or endless pivoting or rotation, but is preferably not designed for a continuous rotational load. Such a rotary joint is preferably used for rotor blade or tower storage for a wind turbine, since both the rotor blade and the tower of the wind turbine for alignment relative to the wind direction must be pivoted by a few degrees and in particular do not require continuous rotation during operation. In the rotor blade bearing, the rotary joint is preferably fixed on the one hand to the rotor blade and on the other hand to the rotor hub. In the tower storage, the rotary joint is preferably located on the tower of the wind turbine, the generator house, if necessary. With rotor gear, rotor, etc., is arranged on the pivot connection pivotally mounted on the tower.

The rotary joint comprises an inner ring and an outer ring, which are arranged coaxially and / or concentrically, and preferably in the radial direction at least partially overlapping each other. On the inner ring and / or the outer ring other components can be attached, screwed or in particular integrally formed, so that, for example, a flange can form the outer ring or the inner ring (with).

It is provided at least one rolling element double row, which is arranged rolling off between the inner ring and the outer ring, so that inner ring and outer ring can be pivoted about a common pivot axis against each other. The Wälzkörperdoppelreihe has at least two rows of rolling elements, which are preferably arranged adjacent to each other and which can be optionally supplemented by further Wälzkörperreihen. Thus, a Wälzkörperdreifachreihe also includes at least one Wälzkörperdoppelreihe. The at least one Wälzkörperdoppelreihe is designed as a radial double row, which significantly radial forces are transmitted and / or follow the rows of rolling elements of the radial double row in the axial direction successively. Alternatively or additionally, the at least one Wälzkörperdoppelreihe formed as a Axialdoppelreihe, wherein decisively axial forces are transmitted and / or wherein the Wälzkörperreihen the Axialdoppelreihe are arranged one after the other in the radial direction. In particular, at least partially align or overlap the Wälzkörperreihen the Radialdoppelreihe in the axial direction and / or the Axialdoppelreihe in the radial direction.

In the context of the invention it is proposed that the at least one Wälzkörperdoppelreihe has a two-point ball row with a two-point contact and a four-point ball row with a four-point contact. Instead of the two-point ball row and a three-point ball row can be provided. The contacts relate in each case to a contact with the raceways of the rolling element rows. In a two-point contact, the forces are transmitted by the balls along a single pressure line from a point of contact of the outer ring to a point of contact of the inner ring. In a four-point contact, loads can be transmitted via two crossed lines of pressure, so that the loads can be transferred in any manner from two points of contact of the outer ring to two points of contact of the inner ring. In a three-point contact loads can be transmitted via two V-shaped arranged pressure lines, wherein the points of contact of the two pressure lines coincide either in a single point of contact of the inner ring or the outer ring.

The two-point ball row is thus limited to transfer loads along its pressure line. Loads that are to be diverted differently from the pressure line between the rings, lead to unfavorable conditions of the rotary joint. On the other hand, this requirement can better be taken over by the four-point sphere row with the four-point contact, since it can cover wide loading angle ranges over the two crossed printing lines. Advantages of the invention can be seen in a higher carrying capacity of the rotary joint through the at least two rows of balls in a load direction. This can result in very good kinematics higher load capacity compared to pure four-point bearings, even with an axially biased state.

In possible embodiments of the invention, the Wälzkörperdoppelreihe is formed as a radial double row, wherein it is preferably provided that at least one further row of rolling elements is available for axial bearing. In another embodiment of the invention, the Wälzkörperdoppelreihe is formed as a Axialdoppelreihe, optionally optionally a radial bearing can be provided.

In a particularly preferred embodiment of the invention, at least one of the Wälzkörperdoppelreihen is formed as the radial double row and at least one of the Wälzkörperdoppelreihen as the Axialdoppelreihe.

In possible developments of the invention, the rotary joint even on two Axialdoppelreihen, which are arranged in the axial direction like a clamp around the radial double row. In these possible embodiments, both the radial double rows and the axial double rows are very tolerant of the introduction angle of the loads.

In the context of the invention disclosure, the pressure angle is defined as the angle which is spanned between the radial plane of the rotary joint and the pressure line. As a reference pressure angle is in a pure radial bearing, which can transmit only radial loads, and / or in a radial row, in particular a radial double row, the pressure angle 0 ° and a pure thrust bearing, which can only transmit axial loads, and / or in an axial row, in particular defined axial double row 90 °.

It is particularly advantageous if the pressure angles of the pressure lines of the four-point ball row for the radial double row and / or for the axial double row each in a range between 15 degrees and 75 degrees, preferably between 20 degrees and 50 degrees and especially between 25 degrees and 45 degrees, and in particular of 30 degrees relative to the reference pressure angle is selected. In particular, the printing lines are arranged symmetrically to the reference printing angle.

In the three-point ball row, it is preferable that the print lines are each set in a range between 10 degrees and 65 degrees, preferably between 15 degrees and 50 degrees, and more preferably between 18 degrees and 40 degrees, and more specifically, 20 degrees relative to the reference pressure angle.

In a preferred embodiment of the invention, the two-point ball row in the axial double row on a pressure angle of 90 degrees and / or rectified with the pivot axis and / or in the radial double row of 0 degrees and / or directed perpendicular to the pivot axis.

Preferably, in combination with the preferred pressure angles of the four-point ball row, there is a particularly preferred embodiment in which the pressure angles of the four-point ball row have a pressure angle of 30 degrees relative to the pressure angle of the two-point ball row. In this embodiment, highest loads in the axial double row in a load direction of 90 degrees or derived in the radial double row of 0 degrees through the rotary joint. At the same time, oblique loads due to the four-point ball row are also removed very well.

In one possible embodiment of the invention, the two-point ball row and the four-point ball row in the radial double ball row are equipped with the same pitch circle diameter.

In an advantageous structural realization, the raceways, in particular at least one of the rings, preferably both rings, that is, the inner ring and the outer ring, made of a tempered steel, which is surface hardened in a preferred development. In particular, the ring or rings is provided in the region of the raceways with a limited Einhärttiefe and not hardened. This embodiment makes the rotary joint less expensive to manufacture.

It is acceptable for the rotary joint that the raceway of at least one Wälzkörperdoppelreihe a slip zone, ie a locally compared to the rest of the career soft area, which may arise in a surface hardening, when the ring is hardened downhill in the direction of rotation. The slip zones can also be relieved geometrically (for example, be set back). As an option, the raceways can also be hardened without slip.

In an advantageous embodiment of the invention, the inner ring and / or the outer ring has mechanical interfaces for connecting the ring or rings to a surrounding construction. For example, the mechanical interfaces are formed as through holes, preferably rectified to the pivot axis or corresponding blind threaded holes. In some embodiments, the inner ring and / or the outer ring may have a radially aligned toothing.

In order for the rotary joint to be able to dissipate the high loads when used in a wind power plant, it is preferred that the rotary joint is designed as a large bearing, wherein the pitch circle diameter and / or the free inner diameter of the rotary joint is greater than 1,500 mm, preferably greater than 2,000 mm and in particular greater than 3,000 mm. Alternatively or additionally, it may be provided that the rolling bodies designed as balls have a diameter greater than 20 mm, preferably greater than 30 mm and / or less than 80 mm, preferably less than 60 mm.

In a preferred embodiment of the invention, the four-point ball row can be designed so that it degenerates at a load perpendicular to the reference pressure angle to an angular ball row with only one oblique line pressure. In particular, it is advantageous if an axial row or the axial double row has a four-point ball row which changes dynamically to an angular ball row in the case of radial loading of the rotary joint within the normal operation of the rotary joint. This dynamic adjustment of the four-point ball row can occur by elastic deformation and / or displacement of the rings to each other.

Another object of the invention relates to a rotor blade or tower bearing for a wind turbine, which according to the features of claim 10 has a rotary joint, as described above or according to one of the preceding claims.

Further features, advantages and effects of the invention will become apparent from the following description of a preferred embodiment of the invention and the accompanying figures. Showing:

1 a schematic longitudinal section along the pivot axis of a rotary joint as a first embodiment of the invention;

2 in the same representation as the 1 a rotary joint as a second embodiment of the invention;

3 in the same representation as the preceding figures, a third embodiment of the invention.

The same or corresponding parts are each provided with the same or corresponding reference numerals.

In the 1 is a rotary joint 1 in a highly schematic longitudinal section through the pivot axis 2 as a first embodiment of the invention. The rotary joint 1 is designed as a rolling bearing assembly and is used for example for the storage of a generator house on a tower of a wind turbine, so that the generator house is pivotable relative to the tower. In another embodiment is about the rotary joint 1 a rotor blade of the wind turbine pivotable about its own longitudinal axis in the rotary joint 1 added.

The rotary joint 1 includes an inner ring 4 and an outer ring 5 which are mutually about the pivot axis 2 over a plurality of as spheres 3 trained rolling elements are stored. inner ring 4 and outer ring 5 are coaxial and / or concentric and overlapping in the radial direction arranged. The outer ring 5 shows axially extending through holes or blind holes 6 in the direction of rotation about the pivot axis 2 are arranged distributed and to connect the outer ring 5 with a bearing partner, such as a surrounding construction are formed. Similarly, the inner ring shows 4 Through holes or blind threaded holes 7 which are also arranged distributed in the direction of rotation and which can be connected to another storage partner.

For example, the outer ring 5 over the through holes 6 with the tower and the inner ring 4 over the through holes 7 be connected to a generator housing. In another embodiment, the outer ring 5 with a rotor hub and the inner ring 4 be connected to the rotor blade. It is also possible that the assignment of the rings 4 . 5 is chosen differently, so that, for example, the inner ring 4 at the rotor hub and the outer ring 6 attached to the rotor blade.

To initiate the pivoting movements, the inner ring 4 an internal toothing 8th which is optionally coupled via a transmission with a motor.

In this embodiment, inner ring 4 and outer ring 5 over two axial double rows 9 and a radial row 10 stored to each other. The axial double rows 9 each have two rows of balls, with one of the rows of balls as a four-point ball row 11 and the other row of balls as a two-point ball row 12 is trained. The printing line 13 the two-point ball row 12 , which is a two-point contact with the adjacent raceways of the outer ring 5 or inner ring 4 is defined, is rectified to the pivot axis 2 or with a print angle of 90 degrees.

The four-point ball series 11 on the other hand shows a four-point contact, with two crossed printing lines 14a , b, in each case a point of contact with the inner ring 4 or the outer ring 5 to have. The opened in the axial direction intermediate angle between the pressure lines 14a , b is about 60 degrees, the pressure angle between a parallel to the pivot axis 2 or the print line 13 and the printing lines 14a , b is about 30 degrees. The two-point ball row 12 and the four-point sphere series 11 one of the axial double rows 9 are in the same axial height of the pivot axis 2 arranged. By using the axial double row 9 with a two-point ball row 12 and a four point ball row 11 this is able to load not only parallel to the pivot axis 2 but also to transfer angled loads or moments.

The radial series 10 In contrast, in this embodiment, it is designed as a cylindrical roller row and can be realized as desired.

The raceways of the axial double rows 9 or the radial row 10 are located in sections of the inner ring 4 or the outer ring 5 , which are made of tempered steel at least in these areas. The raceways are case hardened, in particular are inner ring 4 and outer ring 5 not hardened. In the embodiment shown, the inner ring 4 formed so as to be divided in axial direction for assembly purposes, so that it can be decomposed into at least two parts which are mounted apart in the axial direction. The division of the inner ring 4 allows to bias the rotary joint in the axial direction.

The 2 shows a second embodiment of the invention in the same representation as in the 1 , this time the axial rows 16 Conventionally, for example, as a cylindrical roller train are formed and the radial rows as a radial double row 17 is realized. The radial double row 17 is analogous to the axial double row 9 formed in the preceding figure and rotated in comparison to this by 90 degrees. Thus, the two-point ball row 12 a printing line 13 with a pressure angle of 0 degrees and the four-point sphere series 11 two crossed printing lines 14a , b on, which occupy a radially open angle of 60 degrees or in the axial direction open angle of 120 degrees to each other.

The 3 shows a third embodiment of the invention in the same representation, in which case the axial rows as Axialdoppelreihen 9 like in the 1 and the radial row as a radial double row 17 like in the 2 are formed.

The 4 shows a fourth embodiment of the invention in the same representation, wherein compared to the embodiment in the 1 instead of the two-point ball row 12 a three-point ball row 15 is used. The three-point sphere row 15 points at the balls 3 in each case two V-shaped crossed printing lines 18a , b on, which each have a common point of contact on the track in the inner ring 4 and two spaced-apart contact points on the raceway in the outer ring 5 having. The V-shaped printing lines have an intermediate angle of about 40 °, so that they show a pressure angle of 70 ° or 110 ° with respect to a reference printing angle of 90 °. The three-point sphere row 15 can with the four point ball row 11 also be arranged reversed. It is also possible that such a three-point ball row 15 instead of the four-point ball series 11 in the 1 and 2 is arranged.

LIST OF REFERENCE NUMBERS

1

rotary joint

2

swivel axis

3

roll

4

inner ring

5

outer ring

6

Through holes

7

Through holes

8th

internal gearing

9

Axialdoppelreihe

10

radial series

11

Four-point ball row

12

Two-point ball row

13

pressure line

14a, b

crossed printing lines

15

Three point ball row

16

axial row

17

Radial double row

18a, b

V-shaped pressure lines

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 202007011577 U1 [0004]

Claims (10)

Rotary joint ( 1 ), in particular designed as a rotor blade or turbine bearing for a wind turbine, with an inner ring ( 4 ), with an outer ring ( 5 ), with at least one rolling element double row ( 9 . 17 ), which between the inner ring ( 4 ) and the outer ring ( 5 ) is arranged to roll, so that inner ring ( 4 ) and outer ring ( 5 ) about a common pivot axis ( 2 ) can be pivoted against each other, and wherein the at least one Wälzkörperdoppelreihe ( 9 . 17 ) is formed as a radial double row or as an axial double row, characterized in that the at least one Wälzkörperdoppelreihe ( 9 . 17 ) a two-point ball row ( 12 ) with a two-point contact or a three-point ball row ( 15 ) with a three-point contact and a four-point ball row ( 11 ) having a four-point contact. Rotary joint ( 1 ) according to claim 1, characterized in that at least one of the Wälzkörperdoppelreihen than the Radialdoppelreihe ( 17 ) and at least one of the rolling element double rows as the axial double row ( 9 ) is trained. Rotary joint ( 1 ) according to claim 1 or 2, characterized in that the four-point ball row ( 11 ) has a contact angle between 15 ° and 75 °, preferably between 20 ° and 50 ° and in particular between 25 ° and 45 ° and in particular of 35 °, each measured from a reference pressure angle of 0 ° in a radial row and a reference pressure angle of 90 ° with an axial row. Rotary joint ( 1 ) according to one of the preceding claims, characterized in that the two-point ball row ( 12 ) in the axial double row ( 9 ) a pressure angle of 90 ° and / or in the radial double row ( 17 ) of 0 °. Rotary joint ( 1 ) according to one of the preceding claims, characterized in that the two-point ball row ( 12 ) and the four-point sphere series ( 11 ) in the radial double row ( 17 ) have the same pitch circle diameter. Rotary joint ( 1 ) according to one of the preceding claims, characterized in that the raceway of at least one Wälzkörperdoppelreihe ( 9 . 17 ), of several rolling element double rows ( 9 . 17 ) or all rolling element double rows ( 9 . 17 ) are made of a tempered steel and / or that the track of at least one Wälzkörperdoppelreihe ( 9 . 17 ), of several rolling element double rows ( 9 . 17 ) or all rolling element double rows ( 9 . 17 ) are surface hardened. Rotary joint ( 1 ) according to one of the preceding claims, characterized in that the raceway of at least one Wälzkörperdoppelreihe ( 9 . 17 ), of several rolling element double rows ( 9 . 17 ) or all rolling element double rows ( 9 . 17 ) have a slip zone. Rotary joint ( 1 ) according to one of the preceding claims, characterized in that the inner ring ( 4 ) and / or the outer ring ( 5 ) mechanical interfaces ( 6 . 7 ) for connection to a surrounding structure, wherein the mechanical interfaces are preferably formed as through holes, threaded holes or threaded blind holes. Rotary joint ( 1 ) according to one of the preceding claims, characterized in that the pitch circle diameter and / or the free inner diameter of the rotary joint ( 1 ) greater than 1500 mm, preferably greater than 2000 mm and in particular greater than 3000 mm is formed. Rotor blade or tower bearing for a wind turbine, characterized by a rotary joint ( 1 ) according to any one of the preceding claims.

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