• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Bearing for wind turbines of the employees between the blade (2a) and the hub (2b) and consisting of a fixed ring (3) and a mobile ring (4), in a circular ring, between which the rolling elements interact (5) in its raceways (3c and 4c); and that both the fixed ring (3) and the mobile ring (4) is formed axially divided into an upper ring (3a) (4a) and a lower ring (3b) (4b), and said upper rings (3a) (4a) and lower (3b) (4b) in turn constituted by at least two segments of circular ring (6) (7) positioned in a complementary manner composing among them the desired configuration of the respective ring. (Machine-translation by Google Translate, not legally binding)
    公开号:ES2716935A1
    申请号:ES201731421
    申请日:2017-12-18
    公开日:2019-06-18
    发明作者:Santa Cruz Aitor Zurutuza；Goicoechea Oscar Barbero；Rodriguez Haritz Zabala；Ugarteburu Iker Urresti
    申请人:Laulagun Bearings SL；
    IPC主号:
    专利说明:

    [0001] PERFECTED BEARING FOR WIND TURBINES
    [0002]
    [0003]
    [0004] This invention concerns a bearing for wind turbines of the employees between the blade and the hub.
    [0005]
    [0006] At present it is known to use bearings for wind turbines of employees between the blade and the hub, called "Pitch" bearings, which act on the rotation of the blade of the wind turbine to rotate the blade at a certain angle and to orient it in function of the wind, this angle being the so-called "Pitch angle". These "Pitch" bearings are necessary for the transmission of forces from the blade to the hub, while allowing the necessary rotation to guide the blades depending on the wind to optimize their energy production and avoid damaging efforts for the elements of the wind turbine. This may be the case in extreme wind situations.
    [0007] Currently, the demands of production and energy efficiency of the wind sector market have led to the need to increase the size of the blades of the wind turbine to achieve higher power and therefore an increase in energy production. Likewise so that existing wind turbines are not obsolete and resemble their energy efficiency characteristics to new ones, it has become necessary to recondition these wind turbines to extend their useful life.
    [0008] All these conditions imply an increase in the efforts that the wind turbine must support, which in turn demands greater resistance and reliability to the wind installations, demanding the consequent increase in the diameter, thickness and height of the "Pitch" bearings used between the shovel and hub to withstand the forces produced by the wind, the weight of the blade and the centrifugal force due to the rotation of the wind turbine blade, reaching bearing diameters of more than four meters.
    [0009] The "Pitch" bearings are manufactured from a ring that is forged in the shape of a ring until it takes the diameter of the final ring. These rings forged in a large diameter piece are machined, heat treated and subjected to different production processes to achieve the final configuration of each bearing ring. All this process requires machining, tempering and manipulating rings of large dimensions that make it difficult to move from one production process to another and the manufacturing process itself, increasing manufacturing times and costs. In addition, once the rings that make up the bearing are manufactured, the final assembly of the bearing is carried out by placing the mobile ring inside the fixed ring (or vice versa according to the needs of the installation) and rolling elements are introduced for which it is necessary to foresee a introduction window in both rings. In this way, in addition to the increase in production times and costs, the transport and final assembly difficulties in the field or at home of the wind turbine manufacturer are added. Bearings without segmentation, being formed by complete rings limit their repair and reconditioning of wind turbines since for the assembly itself it is essential to disassemble the bearing of the wind turbine and the bearing itself.
    [0010]
    [0011]
    [0012] Faced with this state of the art, the essential object of this invention is a bearing for wind turbines of the employees between the blade and the hub and consisting of a fixed ring and a mobile ring, in a circular ring, between which the elements interact rolling in its raceways; and that both the fixed ring and the movable ring is formed axially divided into at least one upper ring and one lower ring, and said upper and lower rings being in turn constituted by at least two ring-shaped circular segments positioned complementary by composing among them the desired configuration of the respective ring.
    [0013] In this way, the fixed and mobile rings are divided into segments with a circular crown and axially with an upper and lower part or with as many axial divisions as necessary. Thanks to this configuration, smaller divisions of the bearing are obtained that allow greater ease of manufacture, handling, assembly, transportation and repair for the large dimensions of up to more than four meters in diameter that are currently reaching this type of bearings due to the increase in the size of wind turbine blades.
    [0014] In this way, during manufacture, it is possible to start from smaller material billets and it is not necessary to forge a complete ring of large dimensions with much higher costs. Consequently, material handling is easier and less expensive. Likewise, during the turning of complete rings of such large diameters there is a need to use specific machines for large diameters, while with this invention each of the circular ring segments in which the bearing is divided can be machined in a conventional machining center. In addition, the subsequent thermal quenching and tempering processes do not require such large furnaces. All this translates into greater productivity and reduction of manufacturing time and costs to produce the bearing.
    [0015] In addition to these advantages for its manufacture, once the circular ring segments are obtained, the assembly of the bearing is facilitated. The manipulation is easier since it is divided into elements of smaller dimensions more manipulable even than for complete segments not divided axially. It also has the additional advantage over bearings of complete segments not axially divided that do not require additional holes for the insertion of the rolling elements, which It implies another additional process and locally weaken the bearing's resistant section. While with the combination of axial and radial division once the lower rings are assembled, the rolling elements are introduced and the upper rings are assembled without the need to practice windows for introducing the rolling elements.
    [0016] Additionally, when the assembly is carried out in the field or at the home of the manufacturer of wind turbines, the transport is more space efficient even than other solutions that use complete segments without axial division, being able to use conventional transport limiting the size of the segments to The maximum allowed width of 2.55 meters.
    [0017] Therefore, this invention reduces the manufacturing, transport and assembly times and, consequently, the costs until the final assembly of the complete bearing.
    [0018] Another additional advantage of this configuration is that for other embodiments, in the field repair for complete bearings, it is necessary to disassemble the bearing of the wind turbine and the bearing itself. While with the present invention the circular ring segments can be replaced individually without the need to disassemble the complete bearing.
    [0019] In the present invention, within the circumferential arch of the rings, the positioning joints are angularly offset from the upper ring with respect to the lower ring, avoiding their coincidence.
    [0020] Thanks to this configuration, the problems caused by the bearings divided into circular ring segments without discontinuity between them are avoided. In this type of bearings, the junction positioning joint between joints is continuous transversely along the ring. As a result, the ring segments transmit stresses to the bushing through the connecting screws between the hub and the fixed ring or between the blade and movable ring connection. However, in the present invention and thanks to the axial division it is possible to face the positioning joints of the non-coinciding shape of the upper ring with respect to the lower one, thus one of the segments facing in a mismatched manner transmits the tangential forces, preventing the hub from supporting the tangential forces , which can cause a malfunction and even generation of cracks. This increases the useful life of the wind turbine and reduces maintenance costs considerably in order to achieve a bearing with greater strength, robustness and durability.
    [0021] Another peculiarity of the invention is that it is provided that at least one of the circular ring segments is constituted by a reinforced segment of greater strength than the others, enabling its specific geometric location within the perimeter to raise the resistance of the assembly in that angular section of the bearing. This configuration allows a greater adaptation, versatility and modularity of the bearing. This is especially interesting for this type of bearings "Pitch" since they have a certain angle of rotation and therefore greater forces are produced in certain areas of the bearing. These stresses are accentuated in the contour of the housings of the bearing rings in a particularly critical arc-circumferential zone where the greatest stresses occur during operation due to the force due to the wind, the force due to the weight of the blade and the Centrifugal force due to the rotation of the wind turbine blade. In this way, this type of reinforced segments can be used for the replacement of cracked circular crown segments or to reinforce those critical areas of the bearing, giving it greater strength without having to replace the complete bearing and resize it. The use of reinforced segments by means of the treatment of the material, dimensional increase in height or diameter or by use of different material for a certain segment, provides a versatile bearing and adaptable to the needs of the installation in issue, and that can also be replaced easily. In addition, this same solution allows to locally optimize each bearing area obtaining a bearing that meets the same loads but with much less weight.
    [0022] According to the invention, in their positioning the circular ring segments use the known joining means to be fixed to each other. In this way apart from the union given by the screws that join the mobile ring with the blade and the fixed ring with the bushing, fixing means are used between the circular ring segments such as additional screws, section with overlap of the joint Positioning or adhesive elements, which allow easy disassembly. Thus, the circular ring segments are joined together to support the bearing's own weight and are not dismantled during handling and before they are mounted between the hub and the blade.
    [0023] It is envisaged that in an alternative embodiment only one of the bearing rings will be axially divided into an upper ring and a lower ring and into circular ring segments. In this way, the bearing can be divided into a fixed ring divided both axially and in segments and in a mobile ring without division or vice versa, according to the needs of each installation.
    [0024] In another alternative embodiment it is provided that by maintaining the division into circular ring segments the fixed ring and / or the movable ring do not possess axial division. In this way, depending on the needs of each installation, segments of small dimensions can be used that do not require another axial division and also maintain a lag in the positioning joint, as could be the use of a staggering.
    [0025] It is also provided that the number of circular ring segments to be used in a particular case depends on the dimensions and strength characteristics of each configuration. Thus, for larger diameters the number of sectors to be used will be greater and depending on the critical area where greater efforts will be produced, a segmentation according to these needs will be required.
    [0026] Additionally, it is envisaged that the bearing will consist of one or more rows of rolling elements.
    [0027] This characteristic allows the use of this invention for bearings that use one or more rows of rolling elements according to the needs of the installation, being able to combine the axial division according to the number of rows of rolling elements, to facilitate the assembly and disassembly without the elements wheelers are out of their raceway. It is also contemplated that the rolling elements may be balls, rollers, needles and other configurations used for rolling elements of bearings.
    [0028] And finally, the use of this type of circular ring segment bearings is foreseen in the other wind turbine bearings. Thus, they could be used for other bearings of large dimensions of the wind turbine such as bearings that orient the nacelle in the prevailing direction of the wind and are driven by a number of pinions and reducers placed on its perimeter that engage on the joint ring teeth to the tower. Getting a bearing of great applicability.
    [0029]
    [0030] In order to better understand the nature of the invention, the attached drawings show an industrial embodiment that is purely illustrative and not limiting in its nature.
    [0031] Figure 1 represents in the lower part a view of the wind turbine (2) with a detail for a better clarification of the situation of the bearing (1) in the wind turbine. And in the upper part of figure 1 there is an enlarged detail of the perspective view of said bearing (1), which for a better understanding and to be able to visualize the rolling elements (5) it is represented without two circular ring segments (6) of the fixed ring (3) having a circular ring segment (6) expanded, and without two circular ring segments (7) of the mobile ring (4), one segment of crown being circular (7) expanded. In this case, the fixed ring (3) is the one corresponding to the outer ring and the mobile ring (4) to the inner ring, which may be the opposite according to the needs of the installation.
    [0032] Furthermore, for a better visualization, the positioning joint (8) is represented in thicker line stroke, in this case being an overlapping section for the fixed ring (3) and a straight section for the mobile ring (4).
    [0033] Figure 2 represents a perspective view of the complete bearing (1) once assembled, in this case for positioning joint section (8) straight for both the fixed ring (3) and the mobile ring (4).
    [0034] Figure 3 represents a perspective view of an alternative embodiment of the bearing (1) in which reinforced segments (6a) are used, in this case a reinforced segment (6a) with greater height than the rest of circular ring segments (6) and another reinforced segment (6a) with a height and diameter greater than that of the other circular crown segments (6).
    [0035] In Figure 4 is represented an isometric view of another alternative embodiment with the fixed ring (3) without axial division.
    [0036] In these figures the following references are indicated: 1.-Bearing
    [0037] 2. - Wind turbine
    [0038] 2a. Shovel
    [0039] 2b. Bushing
    [0040] 2 C. Gondola
    [0041] 2d. Tower
    [0042] 3. - Fixed ring
    [0043] 3a. Top ring of the fixed ring (3)
    [0044] 3b. Lower ring of fixed ring (3)
    [0045] 3c. Raceway of the fixed ring (3)
    [0046] 4.- Mobile ring
    [0047] 4a. Top ring of the mobile ring (4)
    [0048] 4b. Bottom ring of the mobile ring (4)
    [0049] 4c. Raceway of the mobile ring (4)
    [0050] 5.- Rolling elements
    [0051] 6. - Circle ring segment of the fixed ring (3)
    [0052] 6a. Reinforced segment of the fixed ring (3)
    [0053] 7. - Circular ring segment of the mobile ring (4)
    [0054] 7a. Reinforced segment of the mobile ring (4) 8.- Positioning joint
    [0055]
    [0056] With reference to the drawings and references listed above, a preferred embodiment of the object of the invention concerning a bearing for wind turbines of the employees between the blade (2a) and the bushing (2b) is illustrated in the attached drawings. it consists of a fixed ring (3) and a mobile ring (4), in a circular ring, between which the rolling elements (5) interact in their raceways (3c and 4c); and that both the fixed ring (3) and the mobile ring (4) is formed axially divided into at least one upper ring (3a) (4a) and one lower ring (3b) (4b), and said rings being upper (3a) ) (4a) and lower (3b) (4b) in turn constituted by at least two segments of circular crown (6) (7) positioned in a complementary manner composing among them the desired configuration of the respective ring ..
    [0057] In Figure 1 it can be seen how this bearing (1) is of the employees between the blade (2a) and the bushing (2b) that currently reach diameters of more than four meters. Thus, the bearing (1) of the present invention is represented by two circular ring segments (6) of the fixed ring (3) and two circular ring segments (7) of the mobile ring (4) without being assembled. A circular ring segment (6) of the upper ring (3a) of the fixed ring (3) and a circular ring segment (7) of the upper ring (4a) of the fixed ring (4) can also be seen. So you can see how segmentation and axial division contributes to the
    [0058]
    [0059]
    [0060] manufacture of elements of smaller dimensions easier to handle and manufacture. In this way, starting from smaller billets of material, the circular crown segments (6) (7) are manufactured with lower manufacturing and transportation costs. And once the final product is obtained, the bearing can be mounted on the wind turbine itself more easily, and thanks to the axial division, it is possible to insert the rolling elements (5) in the raceway (3c) (4c) without having to carry the bearing (1) already mounted to the wind system or having to drill additional holes for the introduction of the rolling elements (5).
    [0061] Thus the final result of the bearing (1) mounted is that shown in figure (2) which shows segments of circular crown (6) and (7) with the positioning joint (8) of vertical section straight. Also in said figure (2) is observed as within the perimeter of the rings (3 and 4) the positioning joints (8) are angularly offset from the upper ring (3a) (4a) with respect to the lower ring (3b) (4b) avoiding their coincidence and thus giving greater robustness and resistance to the bearing (1) than in other segmented bearings.
    [0062] In another embodiment it is provided that at least one of the circular crown segments (6) (7) is constituted by a reinforced segment (6a) (7a) of different strength characteristics, enabling its specific geometric location within the perimeter raise the resistance characteristics of the assembly in that angular section of the bearing (1) as can be seen in figure (3) in which reinforced segments (6a) are used, in this case a reinforced segment (6a) with a height greater than rest of segments of circular crown (6) and another reinforced segment (6a) with height and diameter greater than the rest of circular ring segments (6). This allows a greater versatility and adaptation of the wind turbine, which by means of the replacement only of these reinforced segments (6a) both in the fixed ring (3) and in the mobile ring (4), bearings can be repaired (1) locally deteriorated or adaptation of old wind turbines (2) for greater production and therefore to withstand greater efforts by the bearing (1), and all without the need to disassemble or resize the entire bearing (1).
    [0063] During the assembly it is sometimes necessary, in its positioning, that the circular crown segments (6) (7) use known joining means to be fixed to each other, so that they support their own weight and do not disassemble. It is thus possible to use screws, bolts or other solutions such as the one shown in figure 1, in which an overlap mechanism is used in the circular ring segment (6) as a means of joining segments, which it would only need the use of the usual bolts for connecting the blade and the hub. Adhesives and other joining means could also be used to secure the segments to each other, allowing for easy assembly and disassembly. Another possible solution to be used as means for joining the circular ring segments (6) (7), is the use of adjustable joining means, these being capable of varying the arcolongitudinal dimension of the fixed ring (3) or the ring mobile (4) respectively. Thus, threading elements inserted axially between segments of circular crown (6) (7) and with handling adjustments such as a nut regulates the space corresponding to the separation joint (8), which in some cases during assembly can be wider than normal. In this way, the separation between circular ring segments (6) (7) is avoided, giving continuity to the ring (3) (4) and thus achieving more precisely the transmission of tangential forces by the bearing, which without connecting means they are made only by the contact between the circular ring segments (6) (7) and therefore with less effectiveness. A more effective transmission of tangential forces in the rings (3) (4) is thus achieved by preventing the wear of the bushing (2b).
    [0064] Likewise, it is foreseen that according to the needs of the wind installation, only one of the rings could be divided fixed (3) or mobile (4).
    [0065] And it is also provided that maintaining the division into segments of circular crown (6) (7) the fixed ring (3) and / or the mobile ring (4) do not have axial division. As is the case with the fixed ring (3) of figure (4) in which the movable ring (4) is divided both axially and in segments, while the fixed ring (3) is only divided into circular ring segments ( 6), and furthermore, as can be seen, they maintain in their positioning joint (8) a stepped configuration as a means of joining circular ring segments (6), achieving the same effect as with the angular offset of the circular ring segments. (7) of the mobile ring (4), to avoid the transmission of tangential forces to the hub itself (2b).
    [0066] It is anticipated that for this type of bearing (1) the number of circular crown segments (6) (7) to be used in a particular case depends on the dimensions and strength characteristics of each configuration, depending on the stresses to be supported and the Size of facilities that limit their number by weight or by dimensions necessary for conventional transport.
    [0067] Therefore and by means of this type of bearings, great versatility and adaptability are available and can be used for bearings of one or more rows of rolling elements, in the case of figure 1 the representation would be for two rows of rolling elements, that even for a greater number of rows could be adapted in number of axial divisions. It is also contemplated that the rolling elements can be balls, rollers, needles and other configurations used for rolling elements (5) of bearings (1).
    [0068] Finally, it is expected that this type of bearings can be used in other bearings (1) of the wind turbine (2) such as the bearings (1) that orient the nacelle (2c) in the prevailing direction of the wind. Any other simpler alternative embodiment being possible.
    [0069]
    [0070]
    [0071] The essentiality of this invention does not alter variations in materials, shape, size and arrangement of the component elements, described in a non-limiting manner, this being sufficient to proceed to its reproduction by an expert.
    权利要求:
    Claims (9)
    [1]
    1a.- Bearing for wind turbines of the employees between the blade (2a) and the hub (2b) and consisting of a fixed ring (3) and a mobile ring (4), in a circular ring, between which the rolling elements interact (5) in its raceways (3c and 4c) characterized in that both the fixed ring (3) and the mobile ring (4) is formed axially divided into an upper ring (3a) (4a) and a lower ring (3b) (4b), and said hoops being upper (3a) (4a) and lower (3b) (4b) in turn constituted by at least two segments of circular crown (6) (7) positioned in a complementary manner composing among them the configuration desired of the respective ring.
    [2]
    2a.- Bearing (1) for wind turbines (2) according to the first claim characterized in that within the perimeter arch of the rings (3 and 4), the positioning joints (8) are angularly offset from the upper ring (3a) (4a) with respect to the lower ring (3b) (4b) avoiding their coincidence.
    [3]
    3a.- Bearing (1) for wind turbines (2) according to the preceding claims, characterized in that it is provided that at least one of the segments of circular crown (6) (7) is constituted by a reinforced segment (6a) (7a) of resistance characteristics different from the others, enabling their specific geometric location within the perimeter to raise the resistance characteristics of the assembly in that angular section of the bearing (1).
    [4]
    4a.- Bearing (1) for wind turbines (2) according to the preceding claims, characterized in that in their positioning the circular ring segments (6) (7) use the known joining means to be fixed to each other.
    [5]
    5a.- Bearing (1) for wind turbines (2) according to the preceding claims, characterized in that it is provided that only one of the rings (3 or 4) is divided axially in an upper ring (3a) (4a) and a lower ring (3b) (4b) and in circular ring segments (6) (7).
    [6]
    6a.- Bearing (1) for wind turbines (2) according to the preceding claims, characterized in that it is provided that maintaining the division in circular ring segments (6) (7) the fixed ring (3) and / or the mobile ring (6) 4) do not have axial division.
    [7]
    7a.- Bearing (1) for wind turbines (2) according to the preceding claims, characterized in that it is provided that the number of circular ring segments (6) (7) to be used in a specific case depends on the dimensions and strength characteristics of each configuration.
    [8]
    8a.- Bearing (1) for wind turbines (2) according to the preceding claims, characterized in that it is provided that the bearing (1) is constituted by one or more rows of rolling elements (5).
    [9]
    9a.- Bearing (1) for wind turbines (2) according to the preceding claims, characterized in that the use of this type of bearings (1) of circular ring segments (6) (7) in the other bearings of the wind turbine ( two).
    one
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    同族专利:
    公开号 | 公开日
    ES2716935B2|2020-07-02|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US20120177311A1|2009-08-26|2012-07-12|Mitsubishi Heavy Industries, Ltd.|Planet bearing structure|
    US20120008892A1|2010-07-09|2012-01-12|Schaeffler Technologies Gmbh & Co. Kg|Antifriction bearing for mounting the rotor of a wind power plant|
    WO2013047617A1|2011-09-30|2013-04-04|三菱重工業株式会社|Rotating ring bearing structure for wind wheel and method for replacing rotating ring bearing structure for wind wheel|
    WO2017005264A1|2015-07-06|2017-01-12|Vestas Wind Systems A/S|Segmented pitch ring for a wind turbine blade pitch system|
    US20170067450A1|2015-09-08|2017-03-09|Siemens Aktiengesellschaft|Reinforced bearing of a wind turbine|
    法律状态:
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    优先权:
    申请号 | 申请日 | 专利标题
    ES201731421A|ES2716935B2|2017-12-18|2017-12-18|PERFECTED BEARING FOR WIND TURBINES|ES201731421A| ES2716935B2|2017-12-18|2017-12-18|PERFECTED BEARING FOR WIND TURBINES|
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