DE102015225606A1 - Generator with gear stage - Google Patents

Abstract

Arrangement with at least one planetary stage (101), a first shaft (121) of a second shaft (109) and a generator (103); wherein the planetary stage (101) comprises a ring gear (107), one or more planet wheels (117), a sun gear (119) and a planet carrier (120); and wherein the sun gear (119) is fixed on the first shaft (121). A rotor (123) of the generator (103) is fixed on the first shaft (121).

Description

The invention relates to an arrangement according to the preamble of claim 1.

Such arrangements are particularly suitable for use in the drive train of a wind turbine. A rotor of the wind turbine is rotatably connected to an input shaft of a transmission. The transmission has at least one planetary stage. About the planetary stage, a generator is driven.

Various forms of integration of a gearbox and a generator are known from the prior art. For example, the document discloses EP 2 031 273 A1 a gearbox and a generator, whose housing can be screwed together. An output shaft of the transmission and an input shaft of the generator are rotatably connected to each other by means of a spline.

In the solutions known from the prior art, the transmission usually has two planetary stages connected in series. Hereby, ratios of about 30: 1 to 40: 1 can be realized.

The invention has for its object to couple a transmission with a generator bypassing the known from the prior art solutions inherent disadvantages. In particular, the size and mass of the generator should be reduced.

The size of the generator is a function of the maximum applied to an input shaft of the generator torque. A lower applied torque makes it possible to downsize the generator. At a given input torque applied by the rotor of the wind turbine, the torque applied to the input shaft of the generator can be reduced by increasing the gear ratio of the transmission.

To increase the transmission ratio, the invention provides a planetary stage. An arrangement according to the invention accordingly comprises this planetary stage, a first shaft, a second shaft and the generator. The first shaft and the second shaft are rotatably mounted. In particular, the first shaft and the second shaft are rotatable relative to a fixed component of the transmission, such as to a transmission housing.

The planetary stage includes a ring gear, a planet carrier, one or more planetary gears and a sun gear. The planet gears are each rotatably mounted in the planet carrier. Each planetary gear meshes with the ring gear and / or with the sun gear. Preferably, each planet gear meshes with the ring gear and the sun gear.

Accordingly, the sun gear is fixed on the first shaft. In particular, the sun gear can be fixed exclusively on the first shaft, so that the first shaft carries the sun gear.

The fixation of the sun gear on the first shaft is preferably rotationally fixed, so that no rotation of the sun gear and the first shaft relative to each other is possible about a common axis of rotation. In addition, the fixation of the sun gear may be rigid on the first shaft, so that no relative movements between the sun gear and the second shaft are possible.

According to the invention, a rotor of the generator is fixed on the first shaft. Preferably, the rotor is fixed exclusively on the first shaft, so that the first shaft carries the rotor. In this case, there is at least one rotationally fixed connection between the rotor and the first shaft. Preferably, the rotor is rigidly fixed on the first shaft, so that no relative movements between the rotor and the first shaft are possible.

The inventive arrangement may be connected downstream of a conventional transmission. Due to the additional planetary stage whose gear ratio can be between about 3: 1 and 5: 1, the transmission ratio of the entire drive train increases to about 90: 1 to 200: 1. The generator can be dimensioned accordingly small. Since the rotor is fixed on the first shaft, also eliminates a separate storage of the rotor, so that reduces the number of parts of the generator.

The planet carrier is rotatably designed in a preferred embodiment. This means that the planet carrier rotatably fixed in a fixed component of the transmission, such as in the transmission housing. In particular, the planet carrier can be made stationary. The rotationally fixed arrangement of the planet carrier prevents a lack of lubrication of the planetary gears. Since the planetary stage is coupled directly to the generator at the end of the drive train, high speeds occur here. These would lead to a rotatable planet carrier that the lubricant would flow as a result of the centrifugal forces occurring. A lack of lubrication of the planet gears would be the result. This prevents the non-rotatable arrangement of the planet carrier.

Due to the rotationally fixed planet carrier, the ring gear and the sun gear must be rotatable be stored. The axes of rotation, ie a rotational axis of each of a planetary gear, an axis of rotation of the ring gear and an axis of rotation of the sun gear, preferably run parallel to each other. The axes of rotation of the ring gear and the sun gear are preferably identical. The ring gear and the sun gear are thus rotatably mounted about a common axis of rotation.

According to training, the ring gear is also fixed on the second shaft. In particular, the ring gear can be fixed exclusively on the second shaft. This means that the second shaft carries the ring gear. Preferably, the ring gear and the second shaft are rotationally fixed relative to each other, so that no rotation of the ring gear and the first shaft relative to each other is possible about a common axis of rotation of the ring gear and the second shaft. An integral connection of the ring gear and the first shaft is possible.

Alternatively, the ring gear can be designed rotatably. In this case, the ring gear is non-rotatably fixed in a stationary component of the transmission, such as in the transmission housing. In particular, the ring gear can be made stationary.

Due to the rotationally fixed ring gear of the planet carrier and the sun gear must be rotatably mounted. The axes of rotation, i. an axis of rotation of each of a planetary gear, a rotation axis of the planetary carrier and a rotation axis of the sun gear, preferably run parallel to each other. The axes of rotation of the planet carrier and the sun gear are preferably identical, i. the planet carrier and the sun gear are rotatably mounted about a common axis of rotation.

The rotatably developed planet carrier is fixed on the second shaft. In particular, the planet carrier can be fixed exclusively on the second shaft. This means that the second shaft carries the planet carrier. Preferably, the ring gear and the second shaft are rotatably fixed to each other, so that no rotation of the ring gear and the second shaft relative to each other is possible about a common axis of rotation of the ring gear and the second shaft. Preference is given to an integral connection of the planet carrier and the second shaft.

In a preferred embodiment, the arrangement comprises a first bearing. By means of the first bearing, the first shaft is rotatably mounted in the planet carrier and / or in the transmission housing.

"A shaft is supported by a bearing in a component" generally means that the bearing makes a rotatable connection between the first shaft and the component. The shaft and the component can thus be rotated relative to each other. Translational movements of the shaft and the component relative to each other in the radial direction, i. orthogonal to an axis of rotation of the shaft or component restricts the bearing. A first part of the bearing is equipped with the shaft, a second part of the bearing with the component. In particular, the first part may be an inner ring and the second part may be an outer ring of the bearing, or the first part may be an outer ring and the second part may be an inner ring. The first part and the second part of the bearing are rotatable relative to each other about the said axis of rotation. In the axial direction, the first part and the second part are supported directly on one another or via rolling bodies.

The first bearing is axially arranged at least partially between the sun gear and the rotor in a further preferred development.

When a first component is axially at least partially disposed between a second component and a third component, it generally means that at least a portion of the first component is disposed axially between at least a portion of the second component and at least a portion of the third component. This is the case if and only if a first radially extending plane and a second radially extending plane can be found, the first plane extending between the at least one part of the first component and the at least one part of the second component, without the at least one part the at least one portion of the first component and the at least a portion of the third component, without the at least a portion of the first component and the at least a portion of the first component third component to cut. A radially extending plane is aligned orthogonal to a rotational axis of the first component, the second component and / or the third component.

In addition to the first bearing, the arrangement in a further preferred development on a second camp. By means of the second bearing, the first shaft is rotatable in the second shaft, in the ring gear, in the planet carrier and / or in the transmission housing.

The sun gear is preferably arranged axially at least partially between the first bearing and the second bearing. In this case, the second bearing can be arranged axially at least partially between the second shaft and the sun gear.

Preferably, moreover, the second bearing is disposed axially at least partially between the second shaft and the sun gear.

Alternatively, the first bearing may be disposed axially at least partially between the second bearing and the rotor, wherein the second bearing is disposed axially at least partially between the sun gear and the first bearing. The sun gear is preferably arranged axially at least partially between the second shaft and the second bearing.

For storage of the second wave is used in a preferred embodiment, a third camp. By means of the third bearing, the second shaft is rotatably mounted in the transmission housing. Due to the fixation of the ring gear on the second shaft unnecessary as a result of other bearings for mounting the ring gear.

Preferably, the second shaft is rotatably mounted in the transmission housing exclusively by means of the third and a fourth bearing, wherein the fourth bearing is arranged axially at least partially between the third bearing and the sun gear.

In conventional planetary gears, the sun gear is often floating. The sun gear is provided with degrees of freedom that allow movement of the sun gear in the radial direction. Due to the double bearing of the first shaft by means of the first bearing and the second bearing in the present case, however, no radial movement of the sun gear is possible. Instead, therefore, in a preferred embodiment, the ring gear is fixed radially movable on the first shaft or in the transmission housing. For this purpose, a radially flexible element, i. a resilient to radial displacements element, such as a bead or a screw with radial clearance.

The radially flexible element is fixed in the second shaft or in the transmission housing. The ring gear in turn is fixed in the radially flexible element. The axially flexible element thus enables a relative movement of the ring gear in the radial direction with respect to the second shaft or the transmission housing. This improves the load distribution between the individual planetary gears.

Preferred embodiments of the invention are shown in the figures. Matching reference numbers identify identical or functionally identical characteristics. In detail shows:

1 a first variant of a gear stage with generator;

2 a second variant of a gear stage with generator;

3 a drive train; and

4 a third variant of a gear stage with generator.

In 1 shown is a planetary stage 101 with a generator 103 , The planetary stage 101 is via an input shaft 105 driven. Here is the input shaft 105 rotatably with a rotatable ring gear 107 connected. At the ring gear 107 is a hollow shaft 109 formed, which has a spline 111 connected to the input shaft.

The hollow shaft 109 and thus the ring gear 107 are over camp 113 rotatable in a transmission housing 115 stored. Camps 113 are designed so that they have bending moments of the ring gear 107 be able to record. Tapered roller bearings in a multi-row arrangement are particularly suitable for this purpose.

To the planetary stage 101 belong next to the ring gear 107 planetary gears 117 and a sun wheel 119 , The planet wheels 117 are rotatable in a fixed to the transmission housing 115 connected planet carrier 120 stored. The planet wheels 117 each comb with the ring gear 107 and the sun wheel 119 ,

The sun wheel 119 drives a sun wave 121 at. Next to the sun wheel 119 is also a rotor 123 of the generator 103 on the sun wave 121 appropriate. The rotor 123 is exclusively from the sun wave 121 carried. In particular, the rotor 123 rigid in the sun wave 121 fixed. This means that no relative movements between the rotor 123 and the sun wave 121 possible are.

Because the sun wave 121 the rotor 123 of the generator 103 is not possible, the sun wave 121 radially yielding to radial movements of the sun gear 119 about a radial degree of freedom of the sun's shaft 121 take. The sun wave 121 rather has a single - rotational - degree of freedom.

Nevertheless, a load balance within the planetary stage 101 to allow is the ring gear 107 suspended radially. This purpose is a bead 125 which the ring gear 107 radially movable with the hollow shaft 109 combines.

The planet carrier 120 is with a cover 127 Mistake. Through the cover 127 the sun wave passes through it 121 , The cover 127 serves to the sun wave 121 oil impermeable to the planet carrier 120 seal. In this way, the planetary carrier form 120 and the cover 127 a part of the gearbox 115 ,

With the gearbox 115 or the planet carrier 120 screwed is a generator housing 129 , which is designed in two parts for the purpose of better assembly and disassembly. In particular, the cover seals 127 the gearbox 115 Oil-tight against the generator housing 129 from.

By means of a first camp 131 and a second camp 133 is the sun wave 121 rotatably mounted. The first camp 131 stores the sun wave 121 in the planet carrier 120 , By means of the first camp 131 So it's the sun's wave 121 rotatable in the planet carrier 120 fixed.

At the in 1 illustrated embodiment is the sun wave 121 by means of the second bearing 133 in the ring gear 107 and the hollow shaft 109 stored. The second camp 133 fixes the sun's wave 121 rotatable in the ring gear 107 and the hollow shaft 109 ,

In the axial direction between the first bearing 131 and the second camp 133 are each a part of the sun gear 119 , the planet wheels 117 and the ring gear 107 arranged. The first camp 131 and the second camp 133 can be single or multi-row. Additional bearings for mounting the sun shaft 121 and thus the rotor 123 of the generator 103 are not provided.

This in 2 illustrated embodiment differs in contrast by the arrangement of the second bearing 133 , According to 2 is the sun wave 121 by means of the second bearing 133 not in the ring gear 107 and the hollow shaft 109 stored but together with the first camp 131 in the planet carrier 120 , Again, next to the first camp 131 and the second camp 133 no further bearings for mounting the sun shaft 121 and thus the rotor 123 of the generator 103 intended.

The planetary stage 101 and the generator 103 can like in 3 shown in the drive train 301 a wind turbine can be integrated. The powertrain 301 includes next to the planetary stage 101 a first upstream planetary stage 303 and a second upstream planetary stage 305 , Both planetary stages 303 . 305 have a rotatable planet carrier 309 . 319 , a rotatable sun gear and a fixed ring gear.

One from a rotor of the wind turbine to the generator 103 running torque flow is passed in turn via a rotor shaft 307 , a rotationally fixed with the rotor shaft 307 connected planet carrier 309 the first upstream planetary stage 303 , Planetary gears 311 the first upstream planetary stage 303 that with a ring gear 313 and a sun wheel 315 the first upstream planetary stage 303 comb, the sun wheel 315 the first upstream planetary stage 303 , a rotation with the sun gear 315 connected sun wave 317 the first upstream planetary stage 303 , a non-rotatable with the sun shaft 317 the first upstream planetary stage 303 connected planet carrier 319 the second upstream planetary stage 305 , Planetary gears 321 the second upstream planetary stage 305 that with a fixed ring gear 323 and a rotatable sun gear 325 the second upstream planetary stage 305 comb, the sun wheel 325 the second upstream planetary stage 305 and one rotatable with the sun gear 325 connected sun wave 327 the second upstream planetary stage 305 to the first planetary stage 101 and thus to the generator 103 , The sun wave 327 the second upstream planetary stage 305 thus serves as an input shaft 105 the planetary stage 101 ,

The gear ratio of the two upstream planetary stages 303 . 305 , which is usually between 30: 1 and 40: 1, can be, as described above, by interposing another planetary stage 101 increase. This is how the intermediate planetary stage reaches 101 a gear ratio of 3: 1 to 5: 1. This results in a transmission ratio of the entire drive train 301 from 90: 1 to 200: 1. This, in turn, allows a smaller sized generator 103 to use.

4 shows an embodiment of the planetary stage 101 with a non-rotatable ring gear 107 , Here is in place of the ring gear 107 the planet carrier 120 rotatably with the hollow shaft 109 connected. The planet carrier 120 and the hollow shaft 109 are in particular integrally connected with each other. The ring gear 107 however, it is non-rotatable with the gearbox 115 connected.

The ring gear 107 can with the bead 125 radially movable relative to the transmission housing 115 be hung up. Alternatively, fittings are suitable 401 with which the ring gear 107 in the transmission housing 115 is screwed. The screw connections 401 are such that they have play in the radial direction and thus a radial mobility of the ring gear 107 enable.

LIST OF REFERENCE NUMBERS

101

planetary stage

103

generator

105

input shaft

107

ring gear

109

hollow shaft

111

pass teeth

113

camp

115

gearbox

117

planetary gears

119

sun

120

planet carrier

121

sun wave

123

rotor

125

Beading

127

cover

129

generator housing

131

first camp

133

second camp

301

powertrain

303

first upstream planetary stage

305

second upstream planetary stage

307

rotor shaft

309

planet carrier

311

planetary gears

313

ring gear

315

sun

317

sun wave

319

planet carrier

321

planetary gears

323

planetary gears

325

sun

327

sun wave

401

screw

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

• EP 2031273 A1 [0003]

Claims (12)

Arrangement with at least one planetary stage ( 101 ), a first wave ( 121 ) a second wave ( 109 ) and a generator ( 103 ); where the planetary stage ( 101 ) a ring gear ( 107 ), one or more planet gears ( 117 ), a sun wheel ( 119 ) and a planet carrier ( 120 ); and where the sun wheel ( 119 ) on the first wave ( 121 ) is fixed; characterized in that a rotor ( 123 ) of the generator ( 103 ) on the first wave ( 121 ) is fixed. Arrangement according to claim 1; characterized in that the ring gear ( 107 ) and the planet carrier ( 120 ) is rotationally fixed; the ring gear ( 107 ) on the second wave ( 109 ) is fixed. Arrangement according to claim 1; characterized in that the ring gear ( 107 ) rotatably and the planet carrier ( 120 ) is rotatable. the planet carrier ( 120 ) on the second wave ( 109 ) is fixed. Arrangement according to one of the preceding claims; characterized by a first bearing ( 131 ); where the first wave ( 121 ) by means of the first bearing ( 131 ) rotatable in the planet carrier ( 120 ), in a transmission housing ( 115 ), in the ring gear ( 107 ) and / or in the planet carrier ( 120 ) is stored. Arrangement according to the preceding claim; characterized in that the first bearing ( 131 ) axially at least partially between the sun gear ( 119 ) and the rotor ( 123 ) is arranged. Arrangement according to one of the preceding claims; characterized by a second bearing ( 133 ); where the first wave ( 121 ) by means of the second bearing ( 133 ) rotatable in the planet carrier ( 120 ) and / or in the transmission housing ( 115 ) is stored. Arrangement according to claim 4 or 5 and according to claim 6; characterized in that the sun gear ( 119 ) axially at least partially between the first bearing ( 131 ) and the second bearing ( 133 ) is arranged. Arrangement according to one of claims 6 or 7; characterized in that the second bearing ( 133 ) axially at least partially between the second shaft ( 109 ) and the sun wheel ( 119 ) is arranged. Arrangement according to one of claims 6 or 7; characterized in that the first bearing ( 131 ) axially at least partially between the second bearing ( 133 ) and the rotor ( 123 ) is arranged; the second bearing ( 133 ) axially at least partially between the sun gear ( 119 ) and the first bearing ( 131 ) is arranged. Arrangement according to the preceding claim; characterized in that the sun gear ( 119 ) axially at least partially between the second shaft ( 109 ) and the second bearing ( 133 ) is arranged. Arrangement according to one of the preceding claims; characterized by a third camp ( 113 ); the second wave ( 109 ) by means of the third warehouse ( 113 ) rotatably in the transmission housing ( 115 ) is stored. Arrangement according to one of the preceding claims; characterized in that the ring gear ( 107 ) radially movable on the second shaft ( 109 ) or in the transmission housing ( 115 ) is fixed.

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