DE102018214083A1 - Planetary gear for a wind turbine - Google Patents

Abstract

The invention relates to a planetary gear (1) for a wind power plant, comprising a planet carrier (2) and at least one planet pin (3), the at least one planet pin (3) being provided for supporting a respective planet gear (4), characterized in that that the at least one planet pin (3) is rotatably mounted in the planet carrier (2) by means of a first and second slide bearing (5a, 5b), the two slide bearings (5a, 5b) having a respective inner ring (6a, 6b) and a respective outer ring ( 7a, 7b) with corresponding conical contours (8, 9), the respective inner ring (6a, 6b) being arranged on the planet pin (3) and the respective outer ring (7a, 7b) being arranged on a respective planet carrier cheek (12a, 12b).

Description

The present invention relates to a planetary gear for a wind turbine, comprising a planet carrier. The invention further relates to the use of such a planetary gear in a wind turbine.

The storage of rotating components in wind turbines by means of conical plain bearings is already known from the prior art. From the WO 2014 117 197 A1 For example, a wind turbine transmission with an axis and a gearwheel is known, at least one plain bearing bush being arranged between the axis and the gearwheel. The at least one plain bearing bush is connected to the gearwheel via a conical press fit, the at least one plain bearing bush having a first end face and a second end face. The gear wheel is mounted on an axis, for example a planetary pin, via a slide bearing in the form of a slide bearing bush, in particular a multi-layer slide bearing. This axis can either be formed in one piece with at least part of a gear carrier, in particular a planet carrier, or it is used as a separate component in a bore in the gear carrier.

Based on the prior art, the present invention is based on the object of further developing a planetary gear, and in particular of simplifying assembly and adjustment of the bearing play of a plain bearing. The object is achieved by the subject matter of patent claim 1. Further advantageous embodiments can be found in the dependent claims.

A planetary gear according to the invention for a wind power plant comprises a planet carrier and at least one planet bolt, the at least one planet bolt being intended to support a respective planet gear, the at least one planet bolt being rotatably supported in the planet carrier by means of a first and second slide bearing, the two slide bearings have a respective inner ring and a respective outer ring with corresponding conical contours, the respective inner ring being arranged on the planet pin and the respective outer ring being arranged on a respective planet carrier cheek of the planet carrier. In other words, the respective inner ring is non-rotatably connected to the planet bolt and the respective outer ring is non-rotatably connected to the associated planet carrier cheek. For this purpose, for example, the respective inner ring is pressed onto the planet pin and the respective outer ring is pressed into the associated planet carrier cheek. The two plain bearings are thus integrated in the planet carrier.

The conical or conical contours of the inner rings have a tapering diameter on the sides facing one another, the conical contours of the outer rings having a tapering diameter on the sides facing away from one another. In other words, for example, the contours of the inner rings have a positive shape and the contours of the outer rings have a correspondingly designed negative shape. A lubricating gap with a constant height is thus formed between the contours of the respective inner ring and the associated outer ring. According to one embodiment, the respective inner ring and the associated outer ring slide off one another on the conical contours, with a sliding or contact surface between the conical contours. In a cross-section of the slide bearing, the respective contours on the inner and outer ring are ramp-shaped and opposed, so that together they form a composite rectangle with a slide surface formed between the ramp surfaces.

The planet gear is preferably designed with helical teeth, so that in addition to radial forces, axial forces are also transmitted in the planetary gear. In particular due to the acting axial forces, tilting moments occur on the planet bolt, which are taken up by the slide bearings and guided into the planet carrier. A respective slide bearing is preferably arranged in the planet carrier, in particular in the planet carrier or planet carrier cheeks, on each end face of the planet gear. This enables a space-saving design of the planetary gear, since the planet diameter can be reduced and thus a radial installation space in the planetary stage is reduced. The arrangement of the two plain bearings in the respective planet carrier cheeks results in an improvement in the tilting rigidity of the planet pin, which is particularly advantageous for absorbing the tilting moment from the planet gear.

At least one of the inner rings of the two slide bearings is preferably axially displaceable in order to preload the first and / or the second slide bearing axially, as a result of which a bearing play can be set and the axial position of the respective slide bearing can be secured. The axial displaceability of the respective inner ring is understood to mean that the at least one inner ring can be moved in translation along an axis of rotation or along the planet pin. Only the first inner ring, only the second inner ring, or the first and second inner rings can be axially displaceable. By axially displacing the first and / or second inner ring, a lubrication gap thickness of the respective slide bearing can advantageously be changed. Under the lubrication gap is to be understood as the distance between the first inner ring and the first outer ring, or between the second inner ring and the second outer ring. In particular, the lubrication gap or the lubrication gap thickness is reduced if the first and the second inner ring are moved axially toward one another.

The lubrication gap of the respective slide bearing corresponds to the bearing play of the slide bearing. On the one hand, it is necessary to set the bearing clearance or the specified lubrication gap thickness specified by the manufacturer during commissioning. On the other hand, it may also be necessary to adapt or correct the bearing play or the lubrication gap due to wear, temperature influences or changes in load. Often, a determined increased bearing play means that one or all components of the plain bearing have to be replaced, even though the individual components have not yet reached the wear limit. By adjusting or correcting and adjusting the lubrication gap, the service life of the components or the plain bearing can thus be increased and costs can be saved at the same time.

According to a preferred embodiment, at least one of the inner rings can be axially displaced relative to one another by means of a respective axial securing device in order to axially preload the respective slide bearing. In other words, a separate axial securing device is preferably provided on each of the slide bearings. The axial lock is preferably designed as a shaft nut. The respective axial securing device can therefore be provided, for example, in the form of a thread pairing between the shaft nut and the planet bolt. In other words, the planet bolt has an external thread and the shaft nut has a corresponding internal thread, the shaft nut being screwable onto the planet bolt. The rotational movement of the respective axial securing device generates a translatory movement of the first or the second inner ring in the axial direction as a result of the thread engagement. It is advantageous if there is a free space between the respective inner ring and the planet gear, as a result of which an axial movement of the first and second inner rings is possible. In other words, the inner rings move towards each other by screwing in the two shaft nuts. Furthermore, the respective shaft nut is designed to prevent unwanted axial displacement of the first and / or second inner ring. The respective shaft nut also preferably has a locking ring for axial locking. Thus, the two plain bearings are arranged in the respective planet carrier cheek removable. This is particularly advantageous in relation to assembly, disassembly and / or adjustment of the bearing play or lubrication gap thickness. In other words, this ensures that the plain bearings in the planetary gear can be reached, since both the plain bearings and the associated axial securing device can be mounted, dismantled and / or adjusted from the outside. In particular, the adjustment of the bearing play and the adjustment of the lubrication gap thickness can be carried out with little effort and time, without having to completely dismantle the planetary gear set.

As described above, the axial displacement of the first and / or second inner ring has an effect on the lubrication gap thickness or the bearing play of the respective plain bearing. An unwanted or uncontrolled shifting during operation could thus have a negative impact on the service life, wear or other influences (vibrations).

A respective sliding element is preferably arranged spatially between the respective inner ring and the associated outer ring. This can be, for example, a so-called floating bush or a normal fixed bush. In other words, the sliding element is a separate component which is arranged spatially between the respective inner ring and outer ring in order to reduce friction and wear and comes into contact with the inner ring and outer ring. The respective sliding element advantageously has a contour which is designed to correspond to the conical contour of the respective inner and outer ring. In an advantageous embodiment, this is a respective conical ring, which is arranged in the lubrication gap of the respective slide bearing.

The respective sliding element is preferably formed from a copper-tin alloy, preferably from bronze. The respective inner ring and the associated outer ring are made of a material that is harder in comparison to this. Alternatively, the sliding element can also be made of copper or another suitable soft material with good sliding properties. With such a design of the sliding element, it is advantageous that the respective sliding bearing is comparatively insensitive to dirt and has a high resistance to impacts and vibrations. Furthermore, the respective sliding element has a relatively low sensitivity to counter sliding surfaces with poor surface quality.

The respective inner ring and / or the respective outer ring preferably has a wear-resistant coating. The coating is preferably a carbon coating. The carbon coating is made of, for example formed amorphous carbon, with additional friction and / or wear-reducing alloy elements can be added. Amorphous carbon is also known under the name DLC (Diamond Like Carbon) or diamond-like carbon.

Furthermore, the wear-resistant coating is preferably designed as a tungsten carbide-carbon coating. Tungsten carbide carbon coatings (WC / C coatings) are characterized in particular by their high adhesive strength to the carrier material.

The respective slide bearing can therefore have only one slide element which is arranged between the respective inner ring and the associated outer ring. Alternatively, the respective inner ring and / or the associated outer ring can have the wear-resistant coating in the region of the contact surface, that is to say in the region of the respective conical contour, the respective inner ring sliding off the outer ring. Furthermore, alternatively, both the sliding element can be arranged spatially between the inner and outer ring and a coating can be provided for the inner ring and / or outer ring.

The coating is formed in particular by means of a PVD process in the area of the contact surfaces between the respective inner ring and outer ring. In addition to reducing friction, the carbon coating and the tungsten carbide carbon coating also have positive effects on the corrosion behavior and the fatigue strength of the inner ring and / or the outer ring. As a result, the coated components have improved resistance to fatigue.

According to a further embodiment, the respective outer ring is formed in one piece with a respective planet carrier cheek of the planet carrier. The planet carrier then has a conical bore with the conical contour, the likewise conical inner rings being displaced translationally relative to the respective conical planet carrier bores in order to adjust the bearing play and the lubrication gap thickness.

Furthermore, the use of a planetary gear according to the invention in a wind turbine is proposed.

A preferred exemplary embodiment of the invention is explained in more detail below with reference to the single figure, the same or similar elements being provided with the same reference symbols. Here, the single figure shows a schematic sectional view of a partially illustrated planetary gear according to the invention.

According to the single figure comprises a planetary gear 1 For a - not shown here - wind turbine a planet carrier 2 and a planet bolt 3 , where the planet bolt 3 there is provided a respective planet gear 4 to store. The planet bolt 3 is also by means of a first plain bearing 5a in a first planet carrier cheek 12a of the planet carrier 2 and by means of a second plain bearing 5a in a second planet carrier cheek 12b of the planet carrier 2 rotatably supported, the first plain bearing 5a a first inner ring 6a and a first outer ring 6a and the second plain bearing 5b a second inner ring 6b and a second outer ring 6b exhibit. The inner rings 6a . 6b and the associated outer rings 7a . 7b each have corresponding conical contours 8th . 9 on. The respective inner ring 6a . 6b is axially displaceable in the present case on the planet pin 3 arranged and the respective outer ring 7a . 7b is non-rotatable on the respective planet carrier cheek 12a . 12b arranged. Alternatively, the respective outer ring 7a . 7b in one piece with the respective planet carrier cheek 12a . 12b of the planet carrier 2 be trained.

The conical contours 8th the inner rings 6a . 6b have a tapering diameter on the mutually facing sides of the plain bearings 5a . 5b on, the conical contours 9 the outer rings 7a . 7b a tapered diameter on the opposite sides of the plain bearings 5a . 5b exhibit. So there is between the inner rings 6a . 6b and the associated outer rings 7a . 7b spatially formed a lubrication gap with a lubrication gap thickness, in which also a respective sliding element 11a . 11b is arranged. With the respective sliding element 11a . 11b it is a conical ring, which is spatially between the respective inner ring 6a . 6b and outer ring 7a . 7b in the formed lubrication gap of the respective plain bearing 5a . 5b located. The respective sliding element 11a . 11b is made of bronze in the present case, and comes both on the respective inner ring 6a . 6b and outer ring 7a . 7b to the system, so that there is a frictional resistance in the operation of the planetary gear 1 is reduced. Alternatively or in addition, the inner rings 6a . 6b and the associated outer rings 7a . 7b in the area of the conical contours 8th . 9 have a wear-resistant coating, which is designed, for example, as a carbon coating or tungsten carbide-carbon coating.

The two inner rings 6a . 6b are axially displaceable around the first and second plain bearings 5a . 5b preload axially and to set a bearing play. In other words, the inner rings 6a . 6b translationally along a axis of rotation 13 of the planet bolt 3 towards the planet gear 4 slidable to set a bearing clearance. Furthermore, due to the axial displacement of the inner rings 6a . 6b the lubrication gap thickness, which is spatially between the inner rings 6a . 6b and the associated outer rings 7a . 7b trained, set.

The axial displacement takes place in the present case by a respective axial lock designed as a shaft nut 10 , The planet pin points to this 3 an external thread (not shown here) and the axial lock 10 an internal thread - also not shown here. A rotary movement of the respective axial lock 10 generates an axial movement of the respective inner ring 6a . 6b and clamps the respective slide bearing 5a . 5b axially in front. The axial lock 10 also enables an unwanted axial emergence of the respective inner ring 6a . 6b is prevented.

LIST OF REFERENCE NUMBERS

1

planetary gear

2

planet carrier

3

planet shaft

4

planet

5a

First plain bearing

5b

Second plain bearing

6a

First inner ring

6b

Second inner ring

7a

First outer ring

7b

Second outer ring

8th

First conical contour

9

Second conical contour

10

axial safety

11a

First sliding element

11b

Second sliding element

12a

First planet carrier cheek

12b

Second planet carrier cheek

13

axis of rotation

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included 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.

Patent literature cited

• WO 2014117197 A1 [0002]

Claims (9)

Planetary gear (1) for a wind power plant, comprising a planet carrier (2) and at least one planet pin (3), the at least one planet pin (3) being intended to support a respective planet gear (4), characterized in that the at least one Planet pin (3) is rotatably mounted in the planet carrier (2) by means of a first and second slide bearing (5a, 5b), the two slide bearings (5a, 5b) having a respective inner ring (6a, 6b) and a respective outer ring (7a, 7b) with corresponding conical contours (8, 9), the respective inner ring (6a, 6b) on the planet pin (3) and the respective outer ring (7a, 7b) on a respective planet carrier cheek (12a, 12b). Planetary gear (1) after Claim 1 , characterized in that at least one of the inner rings (6a, 6b) of the two slide bearings (5a, 5b) is axially displaceable in order to axially preload the first and / or the second slide bearing (5a, 5b), as a result of which a bearing play is adjustable and the axial Position of the respective slide bearing (5a, 5b) can be secured. Planetary gear (1) after Claim 2 , characterized in that at least one of the inner rings (6a, 6b) is axially displaceable relative to one another by means of a respective axial lock (10). Planetary gear (1) after Claim 3 , characterized in that the axial lock (10) is designed as a shaft nut. Planetary gear (1) according to one of the preceding claims, characterized in that a respective sliding element (11a, 11b) is arranged spatially between the respective inner ring (6a, 6b) and the associated outer ring (7a, 7b). Planetary gear (1) after Claim 5 , characterized in that the respective sliding element (11a, 11b) is formed from a copper-tin alloy, preferably from bronze. Planetary gear (1) according to one of the preceding claims, characterized in that the respective inner ring (6a, 6b) and / or the respective outer ring (7a, 7b) has a wear-resistant coating. Planetary gear (1) according to one of the preceding claims, characterized in that the respective outer ring (7a, 7b) is formed in one piece with a respective planet carrier cheek (12a, 12b) of the planet carrier (2). Use of a planetary gear (1) according to one of claims 1 to 8 in a wind turbine.

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