Title of Invention

AN APPARATUS FOR ROTATING A ROTOR BLADE OF A WIND POWER INSTALLATION

Abstract

An apparatus for rotating a rotor blade of a wind power installation The present invention relates to a device for rotating the shaft of a rotor blade of a wind energy plant relative to a hub of said wind energy plant. The inventive device comprises a bearing between the structural components and a gearwheel drive for actuating the rotation and adjusting the pitch of the rotor blade. According to the invention a gearwheel of the drive and the bearing are disposed in the volume of a lubricant chamber.

Full Text

The present invention concerns an apparatus for rotating a rotor blade of a wind power installation relative to a hub of the wind power installation, comprising a bearing arrangement between the components and a gear drive for actuation of the rotary movement for adjusting the pitch angle of a rotor blade of a wind power installation. In order on an apparatus to rotate two components relative to each other, they must be supported rotatably relative to each other, which as is known can be implemented for example by means of a plain bearing arrangement or a rolling bearing arrangement. As is known, lubrication for the bearing arrangement is required in order to minimise wear in the bearing arrangement. In order to actuate the rotary movement between the components, it is also necessary to involve a drive which, as is known, can be embodied for example by a gear transmission. If the gear transmission does not involve plastic gears which can only transmit low levels of torque, lubrication is required in the case of such a transmission in order to reduce wear. As is known, lubricants are fed to the apparatus to provide the lubricating effect, more specifically either only when constructing the apparatus, this being known as so-called service life lubrication for example for rolling bearings, or at given intervals, which makes a respective maintenance intervention operation necessary, usually carried out by irained personnel. At this juncture attention is directed generally to the following Dublications, as state of the art: DE 36 25 840 Al, DE 196 34 059 CI; DE 100 21 026 Ul; DE 44 32 986 Al; DE 37 32 730 CI; and DE 44 44 535 Al. The above-indicated publications also inter alia cast light on the ;echnological background of the present invention. A particular situation of use of an apparatus for rotating two :omponents relative to each other is an apparatus for rotating a rotor blade of a wind power installation about the longitudinal axis of the blade with respect of the rotor hub of the wind power installation for adjusting what is known as the pitch angle, that is to say the angle of incidence of the rotor blade with respect to the wind direction into which the rotor is oriented. Here, forces produced on the rotor blade by the wind exert a flexing moment of considerable magnitude on the bearing arrangement, which also adversely influences the wear aspect when rotary movement occurs. In addition, the rotary drive must produce a high rotating movement, not least because of those considerable flexing moments, and only a comparatively small amount of structural space is available for the rotary drive at th blade root where the bearing arrangement is also disposed. Because of the catastrophic consequences in the event of damage and consequential failure, for example because of excessive wear, the lubrication required both for the bearing arrangement and also for the rotary drive is particularly critical and therefore has to be carefully implemented. However, because of poor accessibility to the region to be lubricated, careful lubrication is also particularly complicated and expensive. The object of the present invention, in an apparatus for rotating a rotor blade of a wind power installation relative to a hub of the wind power installation, is to improve the lubrication, of the bearing arrangement and the drive. According to the invention that object is attained by an apparatus for rotating a rotor blade of a wind power installation relative to a hub of the wind power installation, comprising a bearing arrangement between the components and a gear drive for actuating of the rotary movement for adjusting the pitch angle of the rotor blade, characterized in that a gear of the drive and the bearing arrangement are arranged in the volume region of a lubricant chamber. Preferred configurations of the invention are recited in the appendant claims. In accordance with the invention, in an apparatus tor rotating a tirst component in relation to a second component, a bearing arrangement between the components and a gear of the drive for the rotary movement are arranged in the volume region of a lubricant chamber. The bearing arrangement to be lubricated and the gear to be lubricated are consequently disposed in closely juxtaposed positional relationship so that a lubricant which is fed to the gear and/or the bearing arrangement is distributed and interchanged between the bearing and the gear. Preferably the lubricant can be fed to the bearing arrangement and is then distributed from there to the gear. Particularly in the situation where the bearing arrangement and the gear of the apparatus are arranged coaxially and/or substantially in a plane perpendicular to the axis thereof - which is preferably the case for example in an apparatus according to the invention for adjusting the pitch angle at the rotor blade of a wind power installation - the teeth of the gear of the rotary drive and the rolling bodies of the preferred rolling bearing arrangement - in particular a twin-row ball bearing - in the cross-section of the apparatus are so close together, surrounded by a lubricant chamber wall, that lubricant can be distributed through the lubricant chamber from the rolling bodies to the teeth. The invention is described by way of example hereinafter with reference to the accompanying drawings. Figure 1 is a view in cross-section through an apparatus according to the invention for rotating a rotor blade of a wind power installation with respect to the rotor hub thereof, Figure 2 is a view in cross-section through the bearing arrangement and the gear of the apparatus of Figure 1 as a detail from Figure 1, Figure 3 shows a view on to the underside of a rolling bearing, and Figure 4 shows a view in cross-section through the bearings and the gear of a lubricating grease feed arrangement according to the invention. Figure 1 shows an apparatus 2 for rotating the blade root 4 of a rotor blade (not shown) of a wind power installation about the longitudinal axis 6 of the rotor blade with respect to the hub 8 of the wind power installation. It is also possible to see in Figure 1 in particular an electric motor 10 which actuates the rotary movement by way of a transmission 12. In this arrangement, a pinion 14 of the transmission 12 engages a gear 16 which, looking at Figure 2, can be better seen in the detail illustrated therein from Figure 1. The rotational bearing arrangement in the form of a twin-row ball bearing 18 can also be particularly clearly seen in Figure 2. Looking at Figures 1 and 2, it will also be seen that, as measured at the diameter of the rolling bearing 18 and the gear 16 about the axis 6 (Figure 1), the spacing between the rolling bodies of the bearing 18 and the teeth of the gear 16 is very small in the cross-sectional view (Figure 2). In the cross-section shown in Figure 2 the bearing arrangement 18 and the teeth 16 are disposed in the volume region of a lubricant chamber 20 through which lubricating grease can be distributed from the rolling bodies 18 to the teeth 16 over a short distance and as an adequate supply of lubricant. The lubricant chamber 20 is therefore a chamber in the form of a circular ring which is coaxial with the bearing 18 and the gear 16 about the axis 6 and which has two radially outer wall regions 22, 24 of which one 22 is fixed to the rotor blade root 4 and one 24 is fixed to the rotor hub 8. The wall regions 22, 24 are separated from each other by a gap 26 which permits the rotary movement of the two wall portions 22, 24 with the rotor blade 4 and the hub 8 and which is sealed off by a sealing ring 28. Radially inwardly the gap between the wall regions 22 and 24 extends with the gap between the rolling bearing shell portions of the rolling bearing 18 and is there sealed off by a rolling bearing seal 30. Figure 3 is a simplified view on to the underside of the rolling bearing 18. Bores 19 are arranged in the rolling bearing 18. The majority of those bores 19 are through bores. Some of those bores however are in the form of a blind bore. The rolling bearing is screwed to one of the counterpart bearing components through the through bores while the blind bores which are shown in the form of black-filled circles in Figure 3 are not provided for fixing to the counterpart bearing component but for feeding the lubricant for the rolling bearing. Figure 4 shows the hub 8, the blade root and the rolling bearing 18 arranged therebetween. In this Figure the blind bore is denoted by reference 35. In accordance with the invention, a screw is not used here to make a connection between the counterpart bearing components, but a lubricating grease cartridge 32 (lubricant reservoir) is connected to the blind bore 35 by way of a feed duct 34. From the blind bore 35 a first passage 36 and a second passage 38 lead to the rolling bodies which in this Figure are denoted by references 18. The lubricant which is urged under pressure out of the lubricating grease cartridge 32 therefore passes ;hrough the feed duct 34 and the blind bore 35 through the passages 36, 58 into the rolling bearing and lubricates it. Due to the fact that the rolling rearing is sealingly fitted to the counterpart bearing components, the ubricating grease which is urged out of the rolling bearing by the grease vhich is pressed thereinto by the follow-on feed of grease into the bearing ;an only escape to the underside of the rolling bearing into the lubricant :hamber 20. There, that grease is still used to lubricate the pitch drive. As can be seen from Figure 3, such blind bores are distributed over he periphery of the rolling bearing. This provides that the rolling bearing .8 contains fresh lubricating grease at those six locations which are iistributed over its periphery, and that the old lubricating grease issues utwardly into the lubricant chamber at for example those six peripherally Iistributed positions. That provides for lubrication for the blade adjusting Irive over the entire periphery thereof. As will be clearly apparent from Figures 3 and 4 of the description, he lubricant chamber 20 is not for example a lubricant bath which provides jbrication for the blade adjusting drive on the one hand and the rolling learing on the other hand, but rather the fresh lubricating grease is firstly ed to the rolling bearing 18 and, when it issues there, it is still used to jbricate the blade adjusting drive. An oppositely directed flow of lubricant ould transport particles from the blade adjusting drive into the rolling earing and thus give rise to damage to the rolling bearing, which is ibsolutely to be avoided. This means that the path of the lubricating agent in one direction in the sense of a 'one-way street' which is only from the oiling bearing into the lubricant chamber 20 but is not returned. I CLAIM: 1. An apparatus for adjusting a rotor blade (4) of a wind powei installation relative to a hub (8) of the wind power installation, comprising £ bearing arrangement between the components, and a gear drive for actuatior of the rotary movement for adjusting the pitch angle of the rotor blade (4) characterized in that a gear (16) of the drive (10, 12, 14) and the bearing arrangement (18) are arranged in the volume region of a lubricant chambei (20) and in that a lubricant feed is effected through the bearing arrangemen (18). 2. The apparatus as claimed in claim 1, wherein the bearing arrangement (18) and the gear (16) are arranged coaxially. 3. The apparatus as claimed in any one of the preceding claim: wherein the bearing arrangement (18) and the gear (16) are arrangec substantially in a plane perpendicular to the axis (6) thereof. 4. The apparatus as claimed in any one of the preceding claim wherein the bearing arrangement is a rolling bearing (18). 5. The apparatus as claimed in claim 1, wherein the bearin] arrangement is a twin-row bearing (18). 6. The apparatus as claimed in any one of the preceding claim wherein a lubricant feed is provided through the bearing (18). 7. The apparatus as claimed in any of the preceding claims wherein a lubricant reservoir (32) is provided which communicates with the bearing (18) by way of a feed duct (34). 8. The apparatus as claimed in claim 7, wherein the unused lubricant is firstly fed from the lubricant reservoir to the bearing and after use can be fed from the bearing to the lubricant chamber. 9. The apparatus as claimed in claim 8, wherein the feed of lubricant from the lubricant chamber back to the bearing arrangement is not possible. 10. An apparatus for rotating a rotor blade of a wind power installation substantially as herein described with reference to the accompanying drawings.

Documents:

387-chenp-2004 abstract duplicate.jpg

387-chenp-2004 abstract duplicate.pdf

387-chenp-2004 claims duplicate.pdf

387-chenp-2004 description (complete) duplicate.pdf

387-chenp-2004 drawings duplicate.pdf

387-chenp-2004-abstract.pdf

387-chenp-2004-claims.pdf

387-chenp-2004-correspondnece-others.pdf

387-chenp-2004-correspondnece-po.pdf

387-chenp-2004-description(complete).pdf

387-chenp-2004-drawings.pdf

387-chenp-2004-form 1.pdf

387-chenp-2004-form 26.pdf

387-chenp-2004-form 3.pdf

387-chenp-2004-form 5.pdf

387-chenp-2004-other.doc.pdf

387-chenp-2004-pct.pdf