Wind turbine having a hollow, walkable generator shaft

Abstract

Wind turbine having a hollow, walkable generator shaft of a generator assembly and a hollow hub attached to the generator shaft and having at least two blades attached to it, wherein the hub is enterable from the generator shaft and the wind turbine is stoppable in at least two predetermined maintenance positions of the blades, wherein the wind turbine further comprises a safety arrangement, in which a rotatably supported safety element having a door is mounted covering the opening leading from the generator shaft into the hub, wherein a locking arrangement for fixing the safety element in an entering position, in which the door is vertically oriented, is provided.

Claims

1. A wind turbine having a hollow, walkable generator shaft of a generator assembly and a hollow hub attached to the generator shaft and having at least two blades attached to it, wherein the hub is enterable from the generator shaft and the wind turbine is stoppable in at least two predetermined maintenance positions of the blades, wherein the wind turbine further comprises a safety arrangement, in which a rotatably supported safety element having a door is mounted covering the opening leading from the generator shaft into the hub, wherein a locking arrangement for fixing the safety element in an entering position, in which the door is vertically oriented, is provided.

2. The wind turbine according to claim 1, wherein the safety element comprises a fence-like structure, wherein the fence-like structure is a metal structure, in which the door is provided.

3. The wind turbine according to claim 1, wherein the safety element is rotatably supported using rollers mounted to at least one of the generator shaft and the hub.

4. The wind turbine according to claim 1, wherein the locking arrangement comprises a locking lever, wherein the locking lever engages an outer frame of the fence-like structure.

5. The wind turbine according to claim 1, wherein the door comprises a lock controlled by a detection device such that the door only opens when the safety element is in at least one of the entering position and fixed by the locking arrangement.

6. The wind turbine according to claim 5, wherein the detection device comprises a gravity sensor for detecting a predefined orientation of the safety element corresponding to at least one of the entering position, and a fixing sensor for detecting the locking state of the locking arrangement.

7. The wind turbine according to claim 1, wherein the door is configured only to be opened towards the inside of the generator shaft.

8. The wind turbine according to claim 1, wherein the door is spring-loaded towards a closed position of the door.

9. The wind turbine according to claim 1, wherein the safety arrangement further comprises a climbing aid wherein the climbing aid and/or the safety element comprise a suspension such that the climbing aid may be removably suspended into the hub from the threshold of the door.

10. The wind turbine according to claim 1, wherein at least one climbing aid is fixedly installed in the hub.

Description

BRIEF DESCRIPTION

(1) Some of the embodiments will be described in detail, with references to the following Figures, wherein like designations denote like members, wherein:

(2) FIG. 1 shows a wind turbine according to embodiments of the current invention;

(3) FIG. 2 is a view into the interior of the hub in a first position of the blades;

(4) FIG. 3 is a view into the hub in a second position of the blades;

(5) FIG. 4 is a close-up of a portion of a safety arrangement; and

(6) FIG. 5 shows a closer view of the safety arrangement in a door area.

DETAILED DESCRIPTION

(7) FIG. 1 shows a principle drawing of a wind turbine 1 according to embodiments of the current invention. The wind turbine 1 comprises a tower 2 carrying a nacelle 3, in which a generator arrangement 4 comprising a generator 5 is housed. A hollow generator shaft 6, often also called main shaft, is connected to a rotor hub 7. The rotor hub 7 is also hollow such that its interior 8 can be accessed from the interior 9 of the hollow generator shaft 6. In this case, three blades 10 are attached to the hub 7, from which, in FIG. 2, only two are visible due to perspective.

(8) To provide increased safety for a service technician who wants to enter the hub 7 from the generator shaft 6, a safety arrangement generally indicated at 11 is provided, which is now described in more detail regarding the FIGS. 2 to 5.

(9) FIG. 2 shows a view into the interior 8 of the hub 7 in a first maintenance position, wherein a certain one of the blades 10 is in a vertical, upwards pointing orientation. The safety arrangement 11 comprises a safety element 12 covering the opening from the generator shaft 6 to the interior 8 of the hub 7, such that a service technician 13 cannot unintentionally fall in. The safety element 12 comprises an outer, circular frame 14 made of metal, in particular aluminium or an aluminium alloy or thin sheet metal, which is part of a fence-like structure 15 made of the metal. The safety element 12 further comprises a door 16 in the fence-like structure 15.

(10) The safety element 12 is rotationally supported on the generator shaft 6 by rollers 17.

(11) A climbing means or a climbing aid 18, in this case a ladder, is separately provided and may be suspended from the frame 14 or another part of the fence-like structure 15 using corresponding suspension means or suspender before the door 16 is opened. Alternatively, the ladder could be integrated with the frame 14 as a fixed component.

(12) As can be seen, the hub 7 comprises additional climbing aids 19 and the climbing means or ladder or steps 18 is dimensioned to directly adjoin the climbing aid 19 when suspended from the frame 14 in the shown maintenance position.

(13) FIG. 3 shows another maintenance position in which a certain blade points vertically downwards. In this case, the climbing means 18 ends on top of the interior wall 20 of the hub 7 corresponding to the certain blade 10.

(14) The safety arrangement 11 further comprises a locking arrangement 21 to fix the rotatably supported safety element 12 in a certain, predefined entering position in which the door 16 is vertically oriented. Further, during normal operation of the wind turbine 1, the safety element 12 is also fixed to the hub 7 and the generator shaft 6 such that it rotates with them. If maintenance is required, once a certain maintenance position is achieved, for example one of the maintenance positions shown in FIG. 2 or FIG. 3, the service technician 13 approaches the safety arrangement 11 from inside the hollow generator shaft 6. If the safety element 12, in particular the door 16, is not oriented in the entering position, they may unlock the locking arrangement 21 and rotate the rotatably supported safety element 12 into the entering position, where it can be fixed again using the locking arrangement 21. The service technician 13 can now suspend the climbing means 18 into the interior 8 of the hub 7 and open the door 16 to enter, as shown in FIG. 3. As can be seen, the door 16 is configured to only open towards the interior 9 of the generator shaft 6. The service technician 13 can now safely climb into the interior 8 of the hub 7.

(15) As can be seen from FIG. 4, the locking arrangement 21 comprises locking lever 22 using the excenter principle to fix the rotational position of the safety element 12. As can also be seen from FIG. 4, the rollers 17 comprise indentations in which the frame 14 or outer part of the fence-like structure 15 is guided.

(16) The frame 14 is integral with the fence-like structure 15, as can also be seen in FIG. 2 and FIG. 3.

(17) FIG. 5 illustrates that the door 16 is coupled to the fence-like structure 15 by a spring-loading mechanism 23 using a spring 24 such that the door 16 automatically closes and is kept in a closed position by the corresponding restoring force of the spring 24.

(18) Optionally, the safety element 12 may also comprise a lock 25 which is controlled by a detection device 26 such that the door 16 only opens when the safety element 12 is in the entering position. In this example, the detection device 26 may comprise a gravity sensor 27 (acceleration sensor) to detect a predefined orientation of the safety element 12 corresponding to the entering position. In other embodiments, the detection device 26 may further comprise a fixing sensor for detecting the locking state of the locking arrangement 21; in this case, the lock 25 only opens if the safety element 12 is in the entering position and fixed in its rotational position by the locking means or locking device 21. It would also be possible to not use a lock 25 or to use other means for locking and unlocking the lock 25 then the discussed detection device 26, e.g. a manual lock.

(19) It is noted that the safety element 12 may also comprise handles or holds 28 at at least one side of the door 16, further simplifying climbing into or out of the hub 7.

(20) Although the present invention has been disclosed in the form of preferred embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

(21) For the sake of clarity, it is to be understood that the use of “a” or “an” throughout this application does not exclude a plurality, and “comprising” does not exclude other steps or elements.