Bearing assembly and transmission device

Abstract

The invention relates to a bearing assembly and a transmission device. The bearing assembly has at least one planet carrier (54), a stationary element (60) and a bearing portion (94). The planet carrier (54) has a first end region (72) and a second end region (78) axially opposite the first end region. The first end region (72) is designed to be connected to the shaft (16) in a permanently rotationally fixed manner. The second end region (78) forms a first bearing region (90) on which the bearing part (94) is supported with the radial outer side. The stationary element (60) forms a second bearing region (92) on which the bearing part (94) is supported with the radially inner side. The invention further relates to a wind power plant (10).

Description

Technical Field

[0001] This invention relates to bearing assemblies for transmission devices, which have planetary gear sets. Furthermore, the invention also relates to transmission devices and wind power generation facilities. Background Technology

[0002] The transmission device may have a planetary gear set to provide a high transmission ratio. Such a transmission device is used, for example, in wind power or hydropower facilities to generate electricity from wind or water energy. Here, the input shaft of the transmission device can be connected to the rotor shaft of such a facility. The rotor shaft may deform irregularly during operation due to the applied load. If the input shaft of the transmission device is rigidly connected to the rotor shaft, this may cause irregular positional deviations and deformations of the rotating elements of the transmission device, potentially subjecting the corresponding bearings to heavy loads. Furthermore, for example, due to the helical teeth of the planetary gear set, axial forces may act on the bearings. Summary of the Invention

[0003] The first aspect relates to a bearing assembly for a transmission device. The transmission device can be configured to transmit torque from a driving end to a driven end. The transmission device, for example, has at least one planetary gear set. The driving end can be formed, for example, by one rotating element of the planetary gear set, and the driven end by another rotating element of the planetary gear set. The transmission device can also have multiple planetary gear sets that interact with each other. Then, a rotating element of the first planetary gear set (e.g., a planet carrier) can, for example, form the input shaft of the transmission device, and a rotating element of the second planetary gear set can form the output shaft of the transmission device.

[0004] The transmission device is configured, for example, as a transmission device for a wind power generation facility or a hydropower generation facility. Such a facility may, for example, have a rotor and a generator. The rotor can drive the generator via the transmission device to generate electrical energy. The rotor is connected to the transmission device, for example, via a rotor shaft. The rotor may have a horizontal or vertical axis of rotation. The rotor may, for example, have two, three, four, or more rotor blades, which are connected to the rotor shaft via hubs. Bearing assemblies, in turn, are part of the transmission device, which may also be part of a gas turbine or other facility. The transmission device may have a transmission device housing. The transmission device housing may, for example, have one or more housing elements. The transmission device housing may be configured to create an internal space. The driving end of the transmission device is mechanically connected to the rotor, for example, and the driven end of the transmission device is mechanically connected to the generator. The transmission device can be configured to transmit torque from the rotor shaft to the generator.

[0005] The bearing assembly has at least one planet carrier. The planet carrier can be the rotating element of a planetary gear set in a transmission device. The planetary gear set is configured, for example, as a negative planetary gear set or a positive planetary gear set. The planetary gear set, for example, has a sun gear, a planet carrier, and a ring gear. The sun gear, planet carrier, and ring gear of the planetary gear set form the rotating element of the planetary gear set. Each planetary gear set may have one or more planet gears rotatably fastened to the planet carrier. The planet gears may be supported on the planet carrier via planet pins. The planet pins may be constructed individually or integrally with respect to the load-bearing element. The planet gears may be rotatably supported on the planet pins. The planet pins may alternatively or additionally be rotatably supported on the load-bearing element. The planet gears of the planetary gear set mesh, for example, with the sun gear and the ring gear of the planetary gear set, respectively. For this purpose, the sun gear, planet gears, and ring gear of the planetary gear set may each have teeth on their outer circumference. The teeth may be configured as spur teeth or helical teeth. The axis of rotation of the planetary gear set may correspond to the axis of rotation of the rotating element. The corresponding planetary gear set may be arranged coaxially with the rotor shaft, for example. The corresponding rotating elements, planetary gear sets, or the entire transmission can be considered as part of the bearing assembly, or (except for the planet carrier) as a separate part relative to the bearing assembly. In the following text, when referring to planetary gear sets and planet carriers, it means the planet carrier that forms the first support area described below, and the planetary gear set to which the planet carrier belongs.

[0006] The bearing assembly has a stationary component. This stationary component may be part of the transmission housing, thus forming a housing element. The stationary component may be fixed to a base or frame, for example. The stationary component may be axially arranged between the first and second planetary gear sets of the transmission, for example, on the side of the first planetary gear set away from the drive end of the transmission. The stationary component may be permanently anti-rotationally connected to a ring gear, or it may be constituted by the stationary ring gear of the transmission.

[0007] The bearing assembly has a bearing section. The bearing section may, for example, at least at the bearing location, allow two relatively rotatable parts to support each other. The bearing section may, for example, have rotational freedom. The bearing section may be configured to support a planetary carrier on a stationary element. The bearing section may have one or more bearing elements, such as rolling bearings or sliding bearings.

[0008] The planetary carrier has a first end region and a second end region axially opposite to the first end region. These two end regions can be axial end regions of the planetary carrier. The two end regions can be arranged on the axially opposite sides of the planet gears supported on the planetary carrier. The planetary carrier can be constructed as a single piece or in multiple pieces. The first end region can, for example, be formed by a first planetary carrier element, and the second end region can be formed by a second planetary carrier element. These two planetary carrier elements can be permanently connected to each other against relative rotation, for example, by a screw connection.

[0009] The first end region is configured for a permanent, anti-rotational connection to the shaft. For this purpose, the first end region may have radially outward or inward teeth, which may be configured, for example, as interlocking teeth. The shaft may have corresponding teeth, for example, on the end region of the shaft facing the first end region. The connection may be configured, for example, as a press fit, clearance fit, or transition fit. For example, even without applied torque, the tooth flanks of the connected teeth may abut against each other. Alternatively or additionally, the first end region may be screwed or otherwise connected to the shaft. In two permanently anti-rotational connected rotatable elements (e.g., a planetary carrier and a shaft), rotation of one element always causes the same rotation of the other element. The planetary carrier, for example, always rotates in the same direction at the same angular velocity as the shaft. The planetary carrier and shaft, for example, are arranged coaxially. The shaft may be part of a bearing assembly. The shaft may be the shaft of a transmission (e.g., a rotating element), or it may be a separate component relative to the transmission. The shaft may be a drive shaft, by which the transmission can be driven. The shaft may, for example, be a rotor shaft. Planetary carriers can form the drive end of a transmission device.

[0010] The second end region of the planetary carrier constitutes the first support region, on which the bearing is supported radially outward. The second end region may be constructed with one or more radially inward circumferential surfaces, on which the bearing rests. A stationary element constitutes the second support region, on which the bearing rests radially inward. The stationary element may be constructed with one or more radially outward circumferential surfaces, on which the bearing rests. These outward circumferential surfaces may be arranged radially inward relative to other sections of the stationary element. If multiple circumferential surfaces are provided, they may be axially adjacent. With this arrangement, the second planetary carrier can be supported simply and safely. The bearing can have a small diameter, and thus be inexpensive. The bearing can be arranged axially upward next to the teeth of the planetary gear set. Therefore, the effective diameter of the teeth can be selected largely independently of the bearing. Furthermore, the bearing can have a larger lever arm due to its bearing position and its connection to the shaft, which permanently resists relative rotation. This allows forces acting from the shaft to be better supported. For example, this results in only a small overturning of the planetary carrier and, alternatively, an additional eccentric displacement. This results in a smaller additional load entering the teeth of the planetary gear set, leading to a longer service life. Furthermore, the axial length of the bearing assembly, and consequently the transmission device, can be shorter.

[0011] The bearing assembly may have only a single bearing section. The planetary carrier may be supported solely by this bearing section. Alternatively, the planetary carrier may be supported, for example, solely on a shaft (which is permanently anti-rotationally connected to the planetary carrier at a first end region of the planetary carrier) and supported by teeth on other rotating elements. The two support regions may form a single bearing location for the planetary carrier. Both support regions may be arranged in the same axial region. The bearing section may be configured to absorb radial forces and optionally also to absorb axial forces.

[0012] In one embodiment of the bearing assembly, the bearing portion may be configured to absorb axial forces. For example, the bearing portion may be configured to absorb axial forces in both directions. Thus, the bearing portion can also support axial forces introduced by corresponding rotating elements or other planetary gear sets with helical teeth. Therefore, such helical teeth can also be used simply. For example, the bearing portion may have one or more angular contact ball bearings or tapered roller bearings to absorb axial forces. Alternatively, the bearing portion may be configured to absorb essentially only radial forces.

[0013] In one embodiment of the bearing assembly, the bearing section can be configured with two inclined rolling bearings, such as two angular contact ball bearings or tapered roller bearings. This allows the bearing section to be particularly compact radially while still absorbing high loads. Support for axial forces in both directions can also be easily achieved, for example, by arranging them in opposite inclination configurations. Thus, the bearing section can make full use of the available axial structural space.

[0014] In one embodiment of the bearing assembly, the two inclined rolling bearings can be arranged in an X-shape. In the X-shape arrangement, the center of pressure can be axially located between the two rolling bearings. Alternatively, the two inclined rolling bearings can be arranged in an O-shape. In the O-shape arrangement, the center of pressure can be axially located outside the two rolling bearings. The bearing portion can be an adjustable support type bearing portion. The bearing portion can be pre-tensioned.

[0015] In one embodiment of the bearing assembly, one of the two rolling bearings may be larger than the other. The larger rolling bearing can be designed for higher loads. For example, the larger of the two rolling bearings may have larger rolling elements, a larger outer diameter, and alternatively or additionally a smaller inner diameter. The corresponding dimensions that do not result in the larger rolling bearing can be the same size. The two rolling bearings may, for example, be asymmetrical. The camber of the rolling bearings may be different. The larger rolling bearing may, for example, be configured to absorb a larger load. This configuration may be meaningful when, for example, the bearing portion must primarily absorb axial loads in one direction. This is the case, for example, when the transmission has helical gears and operates only or primarily in one direction of rotation. The rotors of wind power and hydroelectric power plants, for example, typically always rotate in only one direction, and thus the axial force also acts in only one direction. With this configuration, the bearing portion can then be optimized for this force. In the case of different rolling bearing sizes, one or both support regions may, for example, be configured as stepped. The first support region may, for example, have a first axial section and a second axial section, wherein the first section has a smaller inner diameter than the second section.

[0016] In one embodiment of the bearing assembly, the stationary element may have a radially extending first wall region. This first wall region may extend from the outside of the transmission to the inner diameter of the bearing portion. The first wall region may divide the internal space into different sub-spaces. The first wall region may be configured to supply lubricant, for example, to the bearing portion, the planet carrier, and alternatively or additionally to the planet gears. The first wall region may extend along the planet carrier, for example. The first wall region may be axially spaced from a second end region of the planet carrier.

[0017] A second wall region extending axially toward the planet carrier, which can be connected to a stationary element of the first wall region. The first and second wall regions can be integrally formed or constructed through different interconnected components. The second wall region can constitute a second support region. The second wall region can also be configured for lubrication supply. The second wall region can, for example, extend axially entirely along the bearing portion. The second wall region can be arranged radially within the bearing portion. The second wall region can, for example, be at least partially arranged axially in the same axial region as the bearing portion. The second wall region can extend axially along the entire bearing portion. The second wall region can be arranged axially in the same region as the first support region. The second wall region extends radially inward relative to the planet carrier, for example. The second wall region extends at least radially inward relative to the second end region of the planet carrier, for example. The second wall region extends radially inward relative to the first support region, for example.

[0018] In one embodiment of the bearing assembly, the bearing portion can be axially fixed. This reliably prevents slippage of the bearing portion. Furthermore, this allows for better absorption of axial forces. Axial fixing of the bearing portion can be achieved on a stationary component and alternatively or additionally on the planetary carrier. For example, axial fixing is achieved by a stop and alternatively or additionally by fixing elements (e.g., retaining rings, screws, and alternative or additional washers).

[0019] In one embodiment of the bearing assembly, the bearing assembly may include a sun gear. The sun gear may be the sun gear of a planetary gear set, to which the planet carrier also belongs. The sun gear may have gear elements and separate shaft elements, which are permanently connected against relative rotation. For example, the gear elements and shaft elements are screwed together. The sun gear may be constructed in at least two pieces, for example. This simplifies assemblability. Furthermore, although the bearing portion may be arranged radially inward to a large extent and the wall sections of the stationary elements may be extended radially inward to a large extent, a large effective diameter can still be easily achieved in the teeth of the sun gear.

[0020] In one embodiment of the bearing assembly, the gear element may have an outer diameter larger than the inner diameter of the stationary element in the second support region. This allows for a larger transmission ratio. In the case of the aforementioned at least two-piece design of the sun gear, assemblability can be facilitated. The stationary element may extend radially inward beyond the outer diameter of the gear element, for example. The stationary element may be axially offset relative to the gear element, particularly offset towards the second end region. The gear element may have an outer diameter larger than the inner diameter of the planet carrier in the second support region.

[0021] The second aspect relates to a transmission device. This transmission device may have a bearing assembly according to the first aspect, and optionally no shaft. Corresponding advantages and other features can be understood from the description of the first aspect, wherein the design of the first aspect also forms the design of the second aspect, and vice versa. The planetary carrier is supported in the transmission device, for example, via the bearing assembly.

[0022] On the other hand, a facility is provided having a transmission device according to the first aspect and, alternatively or additionally, a bearing assembly according to the first aspect. Corresponding advantages and other features can be understood from the description of the first and second aspects, wherein the design of the first or second aspect also forms the design of this other aspect, and vice versa. The facility can, for example, be configured to generate electric current. The facility can, for example, be configured as a wind power generation facility, a hydropower generation facility, or a gas turbine. The facility can have a shaft, for example, a shaft configured as a rotor shaft. The shaft can be permanently anti-rotationally connected to a first end region of the planetary carrier. Attached Figure Description

[0023] Figure 1 A schematic illustration of a wind power generation facility with a transmission device;

[0024] Figure 2 A schematic illustration based on a side sectional view. Figure 1 A first embodiment of a bearing assembly for a transmission device used in wind power generation facilities;

[0025] Figure 3 A schematic illustration based on a side sectional view. Figure 1 A second embodiment of a bearing assembly for a transmission device used in wind power generation facilities. Detailed Implementation

[0026] Figure 1 A horizontally oriented wind power generation facility 10 is described. The wind power generation facility 10 has a rotor 12, which is held on a rotor shaft 16 via a hub 14. The axis of rotation of the rotor shaft 16 extends substantially horizontally. During normal operation, the rotor 12, and consequently the rotor shaft 16, always rotates in only one direction. The rotor shaft 16 is supported in a nacelle 20 via two rolling bearings 18. The rotor shaft 16 is mechanically connected to a generator 24 via a transmission 22. A brake 26 is arranged in the connection between the transmission 22 and the generator 24, acting on the input shaft of the generator 24. The nacelle 20 is rotatably supported at the upper end of a tower 28 anchored to the ground. In another embodiment, the wind power generation facility 10 is constructed as an offshore unit. In addition to the tower 28, the wind power generation facility 10 also has a grid interface 30.

[0027] The transmission device 22 has a bearing assembly, wherein the first embodiment is in Figure 2 The transmission device 22 has a planetary gear set 50. The planetary gear set 50 has a sun gear 52, a planet carrier 54, and a ring gear 56 as rotating elements. A plurality of planet gears 58 are rotatably supported on the planet carrier 54 via corresponding planetary pins 62. The planet gears 58 mesh with the teeth of the ring gear 56 and the sun gear 52, respectively. The ring gear 56 is fixed to a stationary element 60 of the bearing assembly, which forms part of the housing of the transmission device 22.

[0028] The planetary carrier 54 forms part of the bearing assembly and the drive end of the transmission 22. For this purpose, the planetary carrier 54 is permanently connected to the rotor shaft 16, which serves as another shaft, in a manner resistant to relative rotation. To this end, the first end region 72 of the planetary carrier 54 facing the rotor shaft 16 and further facing the rotor 12 has interlocking teeth formed on its radial inner circumference. The rotor shaft 16 has corresponding interlocking teeth formed on its outer circumference at its end region facing the planetary carrier 54. The rotor shaft 16 and the planetary carrier 54 are also secured relative to each other by a plurality of screws 74.

[0029] The sun gear 52 forms the output shaft of the planetary gear set 50 of the transmission 22. In one embodiment, the sun gear 52 also forms the driven end of the transmission 22. In the embodiment shown here, the sun gear 52 is permanently anti-rotationally connected to another planet carrier 76 of another planetary gear set of the transmission 22, which is arranged on the side of the planetary gear set 50 away from the rotor 12, and further arranged on the side of the transmission 22 facing the generator 24. Thus, in one embodiment, the other sun gear of this other planetary gear set forms the driven end of the transmission 22.

[0030] The planetary carrier 54 forms a first support region 90 on its radially inner circumference on the side away from the rotor 12 and further on the side facing the generator 24. The first support region 90 is thus formed by a second end region 78 axially opposed to the first end region 72, which is arranged on the other axially opposite side with respect to the planet gear 58. The stationary element 60 has a radially extending first wall region 80, to which a second wall region 82 extending axially toward the planetary carrier 54 is connected. The second wall region 82 forms a second support region 92 on its radially outer circumference.

[0031] The first wall region 80 is connected to the gear ring 56 via a third wall region 84 that extends axially and is arranged on the outside of the planetary carrier 54. The third wall region 84 forms the outer side of the housing of the transmission device 22.

[0032] The bearing assembly also includes a bearing portion 94 of the transmission 22. The bearing portion 94 is supported radially outward on a first support region 90 and radially inward on a second support region 92. The bearing portion 94 is configured to absorb axial and radial forces. For this purpose, the bearing portion 94 has an inclined first rolling bearing 96 and an inclined second rolling bearing 98. The two inclined rolling bearings 96 and 98 are arranged in an X-shape. The bearing portion 94 is positioned axially relative to the connection between the planetary carrier 54 and the rotor shaft 16, thus better preventing overturning. This reduces the additional load entering the teeth of the planetary gear set 50 due to bending of the rotor shaft 16. The bearing portion 94 is also advantageously arranged within the transmission 22 in terms of structural space.

[0033] The second rolling bearing 98 is larger than the first rolling bearing 96. In the illustrated embodiment, the two rolling bearings 96 and 98 have the same inner diameter. Accordingly, the second support region 92 is constructed as a continuous circumferential surface with a uniform diameter. The corresponding rolling elements and outer diameter of the second rolling bearing 98 are larger than those of the first rolling bearing 96. The first support region 90 is correspondingly constructed in a stepped shape. The bearing portion 94 is thus configured to absorb more axial force toward the second end region 78 and thus the generator 24 than axial force toward the first end region 72 and thus the rotor 12.

[0034] The bearing portion 94 is axially fixed. For this purpose, the first support region 90 has a stop facing the first end region 72. In the opposite direction, the bearing portion 94 is fixed by screws 40 and washers. In a variant, the bearing portion 94 is clamped in the first support region 90. Furthermore, the second support region 92 has a stop facing away from the first end region 72. In the direction facing the first end region 72, the bearing portion 94 is fixed by screws 42 and washers. In a variant, the bearing portion 94 is clamped in the second support region 92. Axial fixing allows for simple installation along the rotation axis of the transmission device 22. In the illustrated example, screws 40 and 42 are tightened from the direction opposite to the first end region 72.

[0035] In the illustrated embodiment, the sun gear 52 has a two-piece structure. The sun gear 52 has a gear element 44 and a separate shaft element 46, which are permanently connected to each other against relative rotation. For this purpose, screws 48 and washers are provided, which can be tightened via a rotor shaft 16 constructed as a hollow shaft. The gear element 44 has an outer diameter larger than the inner diameter of the stationary element 60 within the second wall region 82 and thus the second support region 92. In one embodiment, the bearing portion 94 is assembled before the gear element 44 is assembled onto the shaft element 46.

[0036] exist Figure 3A second embodiment of the bearing assembly of the transmission device 22 is described. Only the differences from the first embodiment are explained. In the second embodiment, the first rolling bearing 96, which faces the first end region 72 and thus the rotor 12 axially, is larger than the second rolling bearing 98. In this embodiment of the bearing portion 94, the outer diameters of the two rolling bearings 96 and 98 are the same. The radially inner circumferential surface forming the first support region 90 can be continuously constructed, wherein a load-reducing notch is provided axially between the two rolling bearings 96 and 98. The rolling elements of the first rolling bearing 96 are larger, thus its inner diameter is smaller than that of the second rolling bearing 98. Therefore, in the second embodiment, the second support region 92 in the second wall region 82 of the stationary element 60 is constructed in a stepped shape. The bearing portion 94 according to the second embodiment can absorb greater axial forces toward the rotor 12. In the example shown, these axial forces are caused by corresponding helical teeth in the second planetary gear set.

[0037] List of reference numerals

[0038] 10 Wind power generation facilities

[0039] 12 rotors

[0040] 14 hubs

[0041] 16 rotor shafts / shafts

[0042] 18 rolling bearings

[0043] 20 cabins

[0044] 22 Transmission device

[0045] 24 generators

[0046] 26 brakes

[0047] 28 towers

[0048] 30 power grid interface

[0049] 40, 42, 48, 74 screws

[0050] 44 Gear Components

[0051] 46-axis components

[0052] 50 planetary gear sets

[0053] 52 Sun Gears

[0054] 54 planetary frames

[0055] 56 gear ring

[0056] 58 Planetary Wheels

[0057] 60 Fixed components

[0058] 62 planetary pins

[0059] 72 First end region

[0060] 76 Another planetary support

[0061] 78 Second end region

[0062] 80 First Wall Area

[0063] 82 Second Wall Area

[0064] 84 Third Wall Area

[0065] 90 First Support Area

[0066] 92 Second Support Area

[0067] 94 bearing

[0068] 96 First Rolling Bearing

[0069] 98 Second Rolling Bearing

Claims

1. A bearing assembly for a transmission device (22), wherein, The bearing assembly has at least one planetary carrier (54), a stationary element (60), and a bearing portion (94), wherein the planetary carrier (54) has a first end region (72) and a second end region (78) axially opposite to the first end region, wherein the first end region (72) is configured for permanent anti-rotational connection with the shaft (16), wherein the second end region (78) constitutes a first support region (90), the bearing portion (94) is supported on the first support region by means of radial outer side, and wherein the stationary element (60) constitutes the second support region (92), the bearing portion (94) is supported on the second support region by means of radial inner side.

2. The bearing assembly according to claim 1, characterized in that, The bearing portion (94) is configured to absorb axial forces.

3. The bearing assembly according to claim 2, characterized in that, The bearing section (94) has two inclined rolling bearings (96, 98).

4. The bearing assembly according to claim 3, characterized in that, The two inclined rolling bearings (96, 98) have an X-shaped arrangement.

5. The bearing assembly according to claim 3 or 4, characterized in that, One of the two rolling bearings (96; 98) is larger than the other of the two rolling bearings (98; 96).

6. The bearing assembly according to any one of the preceding claims, characterized in that, The stationary element (60) has a radially extending first wall region (80) and a second wall region (82) connected to the first wall region and extending axially toward the planet carrier (54), wherein the second wall region (82) forms the second support region (92).

7. The bearing assembly according to any one of the preceding claims, characterized in that, The bearing portion (94) is axially fixed.

8. The bearing assembly according to any one of the preceding claims, characterized in that, The bearing assembly has a sun gear (52), wherein the sun gear (52) has a gear element (44) and a shaft element (46) separate from the gear element, which are permanently connected to each other against relative rotation.

9. The bearing assembly according to claim 8, characterized in that, The gear element (44) has a larger outer diameter than the inner diameter of the stationary element (60) at the second support region (92).

10. A transmission device having a planetary gear set (50) and a bearing assembly according to any one of the preceding claims.

11. A wind power generation facility (10) having a transmission device according to claim 10.

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