INTEGRATED DESIGN OF A SOLAR WAVE

Description

[0001] The invention relates to a wind turbine gearbox according to the preamble of claim 1.

[0002] Wind turbine gearboxes with two planetary stages are known from the state of the art.

[0003] A first planetary stage has a rotatable sun gear integrally connected to a sun shaft. The sun shaft drives a rotatably mounted planet carrier of a second planetary stage via a spline.

[0004] From DE 10 2018 206103 A1 a wind turbine gearbox is known which falls under the wording of the preamble of claim 1.

[0005] US 4,020,716 A discloses an axle drive for land vehicles with a planetary gear. Two planetary gear sets are arranged in series such that a first planetary gear set has a sun gear arranged on a drive shaft and a planet carrier arranged in a stationary hub. A ring gear of the first planetary gear set is fixed in the hub. A second planetary gear set comprises a sun gear supported by an extension of the planet carrier of the first planetary gear set.

[0006] The invention is based on the object of improving a wind turbine gearbox with two planetary stages. This object is achieved by a wind turbine gearbox according to claim 1.

[0007] Preferred developments are contained in the subclaims and result from the following description and the Fig. 1 illustrated embodiment.

[0008] The wind turbine gearbox comprises a first planetary stage and a second planetary stage. A planetary stage is a gear stage with a ring gear, a sun gear, a planet carrier, and one or more planet gears. The planet gears are rotatably mounted in the planet carrier. They each mesh with the sun gear and / or the ring gear. At least two of the three components—ring gear, planet carrier, and sun gear—are independently mounted for rotation about a common axis of rotation. The third component is preferably fixed to the housing. In particular, the ring gear can be fixed to the housing, while the planet carrier and the sun gear are rotatably mounted.

[0009] The sun gear of the first planetary stage and the planet carrier of the second planetary stage are connected to each other by means of a spline. Specifically, the sun gear and the planet carrier are mounted for rotation about a common axis of rotation. The spline prevents rotation of the sun gear and the planet carrier relative to each other. In particular, the spline allows torque to be transmitted from the sun gear to the planet carrier.

[0010] A spline, also called a plug-in spline, consists of an internal toothing and an external toothing. The internal and external teeth are arranged coaxially to each other, meaning they share a common central and rotational axis. The internal and external teeth mesh, creating a positive, non-rotatable connection between the two teeth.

[0011] The sun gear forms the internal gearing in one piece. The sun gear and the internal gearing are connected to each other in one piece.

[0012] The external toothing is formed as a single piece by a first web of the planet carrier or as a single piece by a sun shaft that is integrally connected to the first web. The first web, the external toothing, and possibly the sun shaft are thus connected to one another as a single piece. The planet carrier forms the external toothing as a single piece. The external toothing and the entire planet carrier consist of a single piece. A web of a planet carrier is a support structure that forms bolt seats. A bolt seat, in turn, is a means for securing a planet bolt. The planet bolts each serve to accommodate and support a planet gear. The web is characterized by being axially offset from the planet gears of the respective planetary stage.The cheek and the planetary gears are therefore located on different sides of a plane running radially between the cheek and the planetary gears, i.e. orthogonally aligned to an axis of rotation of at least two rotatable components of the planetary stage.

[0013] The external gearing meshes with the internal gearing. The external gearing is arranged within the internal gearing. Accordingly, the internal gearing has a larger diameter than the external gearing. This in turn makes it possible to use a sun gear and / or a sun shaft with a larger diameter. This reduces the stresses that have to be managed due to the torque to be transmitted. This provides additional freedom in the design of the gearbox. For example, it is possible to transmit greater torques and / or to manufacture the sun shaft from a less resilient but cheaper material. However, thanks to the spline teeth, a sun gear made of a higher-strength material can be used. The one-piece design of the first web and the sun shaft reduces the space required for the arrangement in the axial direction.

[0014] In a preferred embodiment, there is an axial overlap between a working toothing of the sun gear and the spline toothing. The working toothing is characterized in that it meshes with the toothing of one or more planet gears of the first stage. An axial overlap means that at least part of the working toothing and at least part of the spline toothing, in particular at least part of the internal toothing and at least part of the external toothing, lies between two planes oriented radially, i.e. orthogonally to the aforementioned axis of rotation, wherein the planes each touch or intersect all of the aforementioned toothings. The axial overlap between the working toothing and the spline toothing enables the formation of a sun shaft connected integrally to the first cheek and / or the planet carrier.

[0015] Preferably, the sun shaft is designed as a cast part. This is advantageous because cast parts are cost-effective to manufacture.

[0016] In a further preferred embodiment, the sun shaft has a shoulder that forms a first axial abutment relative to the sun gear. The shoulder is thus in contact with the sun gear and prevents displacement of the sun shaft and the sun gear relative to each other in a first axial direction.

[0017] In a preferred embodiment, a second axial abutment is formed by a ring that is joined to the sun shaft. In particular, the ring can be screwed to the sun shaft. The ring is in contact with the sun gear and prevents displacement of the sun shaft and the sun gear relative to each other in a second direction opposite to the first axial direction.

[0018] According to the invention, the wind turbine gearbox is designed with a bearing arrangement. This serves to support the planet carrier. The planet carrier is supported exclusively by the bearing arrangement. Furthermore, the bearing arrangement is joined exclusively to a second flange of the planet carrier. In particular, the bearing arrangement is not joined to the first flange.

[0019] The joining connection between the first bearing arrangement and the second cheek is preferably designed such that one or more outer rings of bearings of the bearing arrangement or one or more inner rings of the bearings are fixed in the second cheek.

[0020] The first flange can be designed as a free-floating flange. Preferably, however, the first flange is supported by the sun shaft and the spline in the planet carrier of the first planetary stage.

[0021] A preferred embodiment of the invention is shown in Fig. 1 In detail: Fig. 1 a wind turbine gearbox.

[0022] In the Fig. 1 The gear shown is a planetary gear with a first planetary stage 101 and a second planetary stage 103. Both planetary stages 101, 103 each comprise a ring gear 101a, 103a, a planet carrier 101b, 103b, planet gears 101c, 103c, and a sun gear 101d, 103d. The planet gears 101c, 103d mesh with the respective ring gear 101a, 103a and the respective sun gear 101d, 103. The planet carriers 101b, 103b are each rotatably mounted in a gear housing 105.

[0023] The planetary carrier 101b of the first planetary stage 101 integrally forms an input shaft 107 of the transmission. An output shaft 109 of the transmission is integrally connected to the sun gear 103d of the second planetary stage 103. A torque introduced into the transmission via the input shaft 107 is transmitted to the output shaft 109 via the first planetary stage 101 and the second planetary stage 103.

[0024] A sun shaft 111 serves as the torque-conducting connection between the two planetary stages 101, 103. This connects the sun gear 101d of the first planetary stage 101 in a rotationally fixed manner to the planet carrier 103b of the second planetary stage 103. The sun shaft 111 is integrally connected to the planet carrier 103b of the second planetary stage 103. A spline 113 establishes a rotationally fixed connection between the sun shaft 111 and the sun gear 101d of the first planetary stage 101. The spline 113 is located inside the sun gear 101d of the first planetary stage 101 and is tangentially enclosed by the sun gear 101d in the circumferential direction.

[0025] The sun shaft 111 forms a web 115. This web rests against the sun gear 101d of the first planetary stage 101 and thus prevents a displacement of the sun shaft 111 in a first axial direction.

[0026] An annular disk 117 is screwed to the end face of the sun shaft 111. The disk 117 rests against a corresponding shoulder of the sun gear 101d of the first planetary stage 101. This prevents displacement of the sun shaft 111 relative to the sun gear 101d of the first planetary stage 101 in a second axial direction opposite to the first axial direction.

[0027] The web 115 and the disk 117 thus fix the sun gear 101d of the first planetary stage 101 and the sun shaft 111 relative to each other against axial displacement. Slight tilting of the sun gear 101d of the first planetary stage 101 and the sun shaft 111 about radial axes of rotation, i.e., axes of rotation orthogonal to a common axis of rotation of the sun gear 101d of the first planetary stage 101 and the sun shaft 111, is enabled by the spline 113. This allows, in particular, load-related positional deviations to be compensated for and the associated incorrect loading to be avoided.

[0028] The planet carrier 103b of the second planetary stage 103 is supported by a single bearing 119 located on the generator side. The bearing 119 is arranged on the generator side, starting from the planet gears 103c of the second planetary stage 103. On the rotor side of the bearing 119, there is no further bearing supporting the planet carrier 103b of the second planetary stage 103. Instead, the planet carrier 103b of the second planetary stage 103 is supported by the sun gear 101d of the first planetary stage 101 via the sun shaft 111. Reference symbol

[0029] 101First planetary stage 101aRing gear 101bPlanet carrier 101cPlanet gear 101dSun gear 103Second planetary stage 103aRing gear 103bPlanet carrier 103cPlanet gear 103dSun gear 105Gearbox housing 107Input shaft 109Output shaft 111Sun shaft 113Spline 115Web 117Disk 119Bearing

Claims

1. Wind-turbine transmission having a first planetary stage (101) and having a second planetary stage (103); wherein a sun gear (101d) of the first planetary stage (101) and a planet carrier (103b) of the second planetary stage (103) are connected to one another in a rotationally conjoint manner by means of a spline toothing (113); wherein the sun gear (101d) forms an inner toothing in one piece; wherein a first side piece of the planet carrier (103b) or a sun shaft (111) connected in one piece to the first side piece forms an outer toothing of the spline toothing (113) in one piece; and wherein the outer toothing and the entire planet carrier (103b) consist of one piece; characterized in that the planet carrier (103b) is mounted by means of precisely one bearing arrangement (119), which is joined exclusively to a second side piece of the planet carrier (103b) .

2. Wind-turbine transmission according to Claim 1; characterized by an axial overlap between a working toothing of the sun gear (101d) and the spline toothing (113).

3. Wind-turbine transmission according to either of the preceding claims; characterized in that the sun shaft (111) is cast.

4. Wind-turbine transmission according to one of the preceding claims; characterized in that the sun shaft (111) has a shoulder (115) which forms a first axial abutment with respect to the sun gear (101d).

5. Wind-turbine transmission according to the preceding claim; characterized by a ring (117) which is joined to the sun shaft (111) and forms a second axial abutment with respect to the sun gear (101d).