Claims:We claim:

1. A rotor locking device for locking a rotor (5) of a wind turbine (1), the rotor locking device (12) comprising
- a holding element (13, 13a) for holding a pin (14),
- a pin (14) for locking a rotor (5), and
- a pivot shaft (15) for securing the pin (14) at the holding element (13, 13a),
characterized in that
the pin (14) and the pivot shaft (15) are arranged at the holding element (13, 13a) in such a way that the pin (14) can pivot around the pivot shaft (15) from an unlocked position to a locked position and vice versa.

2. The rotor locking device according to claim 1, characterized in that the pin (14) has a bore (16), wherein the pivot shaft (15) is pushed through the bore (16).

3. The rotor locking device according to claim 1 or 2, characterized in that the holding element (13, 13a) comprises two lugs (17, 18), wherein the two lugs are arranged spaced opposite the pin (14) is arranged and at the space (19) be-tween the two lugs (17, 18).

4. The rotor locking device according to claim 3, characterized in that each lug (17, 18) has a bore (20, 21), which are arranged in alignment to each other.

5. The rotor locking device according to claims 2 to 4, characterized in that the pin-bore (16) as well as the lug-bores (20, 21) are arranged in alignment and the pivot shaft (15) is pushed through the pin-bore (16) as well as the lug–bores (20, 21).

6. The rotor locking device according to claim 5, characterized in that the pivot shaft (15) has in the lug-bores (20, 21), an interference fit and in the pin-bore (16), a clearance fit.

7. The rotor locking device according to claim 5, characterized in that the pivot shaft (15) has in the pin-bore (16), an interference fit and in the lug-bores (20 ,21), a clearance fit.

8. The rotor locking device according to one of the preceding claims, charac-terized in that the pin (14) having a recess (22) for receiving a pin locking element (32).

9. The rotor locking device according to one of the preceding claims, charac-terized by a pin locking element (32) for securing the pin (14) in locked posi-tion and/or in unlocked position.

10. A rotor locking arrangement for locking a rotor (5) of a wind turbine (1), the rotor locking arrangement (23) comprising
- a stator element (24),
- a rotor shaft (25) and
- a brake disk (26) which is arranged at the rotor shaft (25) besides the stator element (24),
characterized by
at least one rotor locking device (12) according to one of the claims 1 to 9, which is arranged at the stator element (24).

11. The rotor locking arrangement according to claim 10, characterized in that the brake disk (26) having at least three recesses (27, 28, 29), preferred at least six recesses and more preferred nine recesses , wherein one recess (27, 28, 29) can receive one pin (14).

12. The rotor locking arrangement according to claim 10 or 11, characterized in that the brake disk (26) has nine recesses, which are arranged in three trio groups.

13. The rotor locking arrangement according to claim 11 or 12, characterized in that in locked position the pin (14) lies in the recess (28) and in unlocked po-sition the recess (28) is free.

14. A nacelle of a wind turbine comprising a rotor locking arrangement according to one of the claims 10 to 13.

15. A wind turbine having a nacelle and a rotor characterized by a rotor locking arrangement according to one of the claims 10 to 13.
, Description:FIELD OF INVENTION

The present invention is directed to a rotor locking device for locking a rotor of a wind turbine, a rotor locking arrangement comprising said rotor locking device, a nacelle of a wind turbine having said rotor locking arrangement and a wind tur-bine comprising said rotor locking arrangement.

BACKGROUND

For safety reasons work at the drive train is only permitted if a form-closed rotor lock is applied. To apply this form-closed rotor lock the rotor needs to be in one of the certain number of possible locked positions. The experience of maintenance personnel has shown that the introduction of the form-closed rotor lock is difficult and a time consuming task, because the lock device and the brake disk, especially the holes of the brake disk must be set in the right position to the pin of the lock-ing device. Only in this position the rotor lock can be applied.

In general, it is determined that because of increasing the power of wind turbines also the rotor increases, especially the diameter and the weight inertia increases. At the same time the diameter of the brake disk of the rotor stays the same or even is decreased. Consequently, in case of maintenance / repair work the force to be applied for locking the rotor increases as well. In result of this, applying the rotor lock will be more difficult.

Different solutions for a rotor locking devices are disclosed in CN 102 635 516 A, WO 2018 054 434 A1, KR 10 2014 0 072 561 A1 and CN 101 535 635 A. These locking devices use motor driven or hydraulic driven locking pins. Such arrange-ments are high cost intensive in purchase and maintenance.

OBJECT OF THE INVENTION

The object of the present invention is to provide a rotor locking device which overcomes the disadvantages of the prior art, in particular which allows an easy and uncomplicated introduction of the pin and which is cheap in purchase and maintenance.

SUMMARY OF THE INVENTION

The present invention provides a rotor locking device for locking a rotor of a wind turbine, the locking device comprises a holding element for holding a pin for lock-ing the rotor and a pivot shaft for securing the pin at the holding element, wherein the pin and the pivot shaft are arranged at the holding element in such a way that the pin can pivot around the pivot shaft from an unlocked position to a locked position and vice versa. This is an advantageous construction which can work without additional drives. In particular, the rotor locking device is hand operated.

In a preferred embodiment, the pin has a bore, wherein the pivot shaft is pushed through the bore.

In a further preferred embodiment, the holding element comprises two lugs, wherein the two lugs are arranged spaced opposite and the pin is arranged at the space between the two lugs.

In a more preferred embodiment, each lug has a bore, which are arranged in alignment to each other.

In a further preferred embodiment, the pin-bore as well as the lug-bores are ar-ranged in alignment and the pivot shaft is pushed through the pin-bore as well as the lug–bores. Advantageously, the pivot shaft extends over the lugs in such a way that at the ends of the pivot shaft can fixed via nut(s), screw-nut connection, securing pins or something else at the holding element. However, other fixing methods are possible like over an interference fit (also called press fit).

In a more preferred embodiment, the pivot shaft has in the lug-bores, an interfer-ence fit (also called press fit) and in the pin-bore, a clearance fit. This allows an easy mounting of the pivot shaft and at the same time a secure holding at the holding element and nevertheless the pin can pivot around the pivot shaft.

In an alternative embodiment, the pivot shaft has in the pin-bore, an interference fit and in the lug-bores, a clearance fit. This allows a pivot of the pin via the pivot shaft. Advantageously, the pivot shaft has on each end or on both ends, means for rotating the pivot shaft. In result, the pin will follow the rotation of the pivot shaft and will pivot from an unlocked position to a locked position or vice versa.

In a further preferred embodiment, the pin has a recess for receiving a pin locking element. Advantageously, the pin locking element is a screw, an additional secur-ing pin or something to block/catch the pin in the rear side.

In a further embodiment, the rotor locking device is characterized by a pin locking element for securing the pin in locked position and/or in unlocked position.

A further aspect of the invention is directed to a rotor locking arrangement for locking a rotor of a wind turbine. The rotor locking arrangement comprises a stator element, a rotor shaft and a brake disk which is arranged at the rotor shaft besides the stator element, characterized by at least one rotor locking device de-scribed above, which is arranged at the stator element. Advantageously, the stator element is a main frame of a wind turbine. In particular, the holding element is fixed to the stator element respectively to the main frame via a detachable connec-tion or permanent connection. Alternatively, the holding element can be integrally formed with the stator element; in particular the holding element and the stator element could be a moulding part. For example, a detachable connection can be realized by screws, rivets or the like. For example, a permanent connection can be realized as an adhesive connection or a welded connection. Preferably, if the pin is in locked position, then the pin lies parallel to the rotor shaft.

In a more preferred embodiment of the arrangement, the brake disk has at least three recesses, preferred at least six recesses and more preferred nine recesses, wherein one recess can receive one pin. Advantageously, the corresponding re-cesses are arranged in an angle of 120°.

In a more preferred embodiment of the arrangement, the brake disk has nine re-cesses, which are arranged in three trio groups. Advantageously, the middle re-cesses of each trio group are arranged in an angle of 120° and 240° respectively. Because of the trio grouped recesses the rotor locking arrangement can comprise up to three rotor locking devices, which are arranged beside each other in an area of one trio group. In result, in each recess of a trio group is arranged one pin of a rotor locking device. This ensures an advantageous distribution of force for lock-ing the rotor.

In a further preferred embodiment of the arrangement, in locked position the pin lies in the recess and in unlocked position the recess is free.

A further aspect of the invention is directed to a nacelle of a wind turbine com-prising a rotor locking arrangement described above.

A further aspect of the invention is directed to a wind turbine having a nacelle and a rotor characterized by a rotor locking arrangement described above.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be explained in more detail with respect to exemplary embodiments with reference to the enclosed drawings, wherein:

Figure 1 shows a perspective sectional view of a wind turbine;

Figure 2 shows a perspective view of a rotor locking device, wherein the pin is in locked position;

Figure 3 shows a perspective view of the rotor locking device according to Fig. 1, wherein the pin is in unlocked position

Figure 4 shows a perspective view of a pin of the rotor locking device ac-cording to Fig. 1 in more detail and

Figure 5 shows a perspective sectional view of a rotor locking arrangement;

Figure 6 shows a perspective sectional view of a rotor locking arrangement, wherein the pin is secured with a pin locking element in locked po-sition and

Figure 7 shows a perspective sectional view of a rotor locking arrangement according to Fig. 6, wherein the pin is secured with a pin locking element in unlocked position.

The foregoing and other aspects will become apparent from the following detailed description of the invention when considered in conjunction with the accompany-ing drawing figures.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 depicts a schematic view of a wind turbine (1) with a tower (2) and a nacelle (3). Depending on given requirements the wind turbine (1) can be used for offshore or onshore applications. The nacelle (3) is rotatable, mounted on the tow-er (2). The nacelle (3) incorporates beside others a main frame and (indicated in Fig. 5) a number of components of a drive train chain (4) comprising for example a rotor shaft (indicated in Fig. 5). The nacelle (3) also incorporates a generator (not shown) connected with a plurality of electrical components (not shown). Further the nacelle (3) comprises a yaw system (not shown) for rotating the nacelle (3). Said rotor shaft is connected to a rotor (5). The rotor (5) comprises three rotor blades (6) which are mounted to a hub (7). The hub (7) is connected to the rotor shaft (indicated in Fig. 5) of the drive train chain (4). The rotor blades (6) are ad-justably mounted on the hub (7). This is realized by means of pitch drives (8), said pitch drives (8) being part of a pitch system (not shown). The pitch system con-trols the rotor speed to given set points. By means of pitch-drives (8), the rotor blades (6) may be moved about a rotor blade (6) axes into different pitch posi-tions, said rotor blade (6) axis extending in an axial direction of the rotor blades (6). Each rotor blade (6) is connected to the hub (7) via its pitch-drive (8). The nacelle (3) is covered by a nacelle cover (9), which has a nacelle cover interface (10). The hub (7) is covered by a spinner (11).

In the following by reference to the Figs. 2 to 3, one embodiment of the rotor locking device (12) is described in more detail.

The rotor locking device (12) comprises a holding element (13) for holding a pin (14) for locking the rotor (5) and a pivot shaft (15). The pin (14) and the pivot shaft (15) are arranged at the holding element (13) in such a way that the pin (14) can pivot around the pivot shaft (15) from a locked position (Fig. 2) to an un-locked position (Fig. 3) and vice versa. Therefore, the pin (14) is mounted to the pivot shaft (15), wherein the pin (14) having a bore (16), hereinafter called pin-bore (see Fig. 4). The pivot shaft (15) is pushed through the pin-bore (16). The holding element (13) comprises two lugs (17, 18), wherein the two lugs (17, 18) are arranged spaced opposite and at the space (19) between the two lugs (17, 18) the pin (14) is arranged. For mounting the pivot shaft (15) each lug (17, 18) com-prises a bore (20, 21), hereinafter called lug-bore respectively lug-bores, which are arranged in alignment to each other. For assembling the rotor locking device (12) the pin-bore (16) as well as the lug-bores (20, 21) are arranged in alignment and the pivot shaft (15) is pushed through the pin-bore (16) as well as the lug–bores (21, 21). According to the shown embodiment the pivot shaft (15) has in the lug-bores (20, 21), an interference fit and in the pin-bore, (16) a clearance fit. In alternative, the pivot shaft (15) has in the pin-bore (16), an interference fit and in the lug-bores (20, 21), a clearance fit. However, other fixings are also possible.

As can be best seen in Fig. 4, the pin (14) has a recess (22), hereinafter called pin-recess, for receiving a screw, an additional securing pin or something to block/catch the pin in the rear side (not shown) for securing the pin (14) in locked position as well as in unlocked position. The pin locking element could be a screw, which will be described in detail below. When the pin (14) is in locked position the pin locking element can be applied in the pin-recess (22). At this arrangement the pin (14) is secured against leaving the locked position. Further, a part of the force to be applied for locking the rotor could be received by the pin locking element, in particular the screw. Otherwise, when the pin (14) is in unlocked position the pin locking element can be applied to the outer surface of the pin (14). At this arrangement the pin (14) is secured against leaving the unlocked position, especially pivoting to the locked position, so the rotor would be locked in undesirable situations. This undesirable situation is when the rotor (5) rotates in nominal state, if then the pin (14) is pivoting in locked position, heavy damages can be caused.

Figure 5 depicts a perspective view of a rotor locking arrangement (23) having a stator element (24), a rotor shaft (25) and a brake disk (26), which is arranged at the rotor shaft (25) besides the stator element (24), and the rotor locking device (12) as described above, which is arranged at the stator element (24) besides the brake disk (26). In the shown embodiment, the stator element (24) is the main frame of the wind turbine (1), so hereinafter it will be referred as main frame (24). The holding element (13) of the rotor locking device (12) is integrally formed with the main frame (24). The brake disk (26) comprises nine recesses (27, 28, 29), which are arranged in three trio groups, however Fig. 5 only shows three recesses (27, 28, 29) arranged in one trio group. It’s clear that the other both trio groups are arranged in an angle of 120° and 240o respectively. As shown, in the locked position the pin (14) lies in the recess (28). At the stator sided end (30) of the pin (14) there can be arranged a pin locking element (not shown) as described above. As can be seen in locked position the pin (14) lies axial to the rotor shaft (25). The recesses (27, 28, 29), especially recess 28, allows a visible identification of the position of the recesses (27, 28, 29).

Further the recesses (27, 28, 29) of the brake disk (26) have rounded or beveled edges (31). These edges (31) serve as positioning aids for the pin (14).

As can be best seen in Fig. 3 the pin (14) is arranged in such a way that in the un-locked position, the pin (14) is partly visible. So the pin can be seen by the maintenance personnel. Together with the recesses (27, 28, 29), especially recess 28, it will be allowed that maintenance personnel can position the recess (28) rela-tive to the pin (14), so that the pin (14) can pivot in locked position.

Figures 6 and 7 show an embodiment of the rotor locking arrangement (23) that comprises a pin locking element (32). The pin locking element (32) can be a screw, an additional securing pin or something to block/catch the pin in the rear side. Before describing this embodiment in detail it should be pointed out that the pin locking element (32) is a part of the rotor locking device (12). For arranging the pin locking element (32) the holding element (13) has to be modified, therefore the holding element will be referred as holding element (13a). The difference is that the holding element (13a) has a connection lug (33) for connecting the lugs 17, 18. And the connection lug (33) comprises a bore (34) for receiving the pin locking element (32). As can be seen in Fig. 6 for securing the pin (14) the pin locking element (32) engages in the pin-recess (22) once and is held at the bore (34) of the connection lug (33) twice. This arrangement allows securing of the pin (14) on one hand and force distribution to the holding element (13a) on the other hand. By pulling the pin locking element (32) out of the pin-recess (22) the pin (14) is free and can pivot in unlocked position, as shown in Fig. 7.

Apart from that, the rotor locking device (12) as well as the rotor locking ar-rangement (23) is the same as described above. Also the holding element (13a) is integrally formed with the stator element (24). In case the stator element is the main frame (24), the holding element (13a) is integrally formed with the main frame (24). So the force for locking the rotor (5) will be distributed from the hold-ing element (13a) to the stator element too. This optimizes the force distribution overall.

List of reference signs

1 wind turbine
2 tower
3 nacelle
4 drive train chain
5 rotor
6 rotor blades
7 hub
8 pitch drives
9 nacelle cover
10 nacelle cover interface
11 spinner
12 rotor locking device
13, 13a holding element
14 pin
15 pivot shaft
16 pin-bore
17, 18 lug
19 space
20, 21 lug-bore
22 pin-recess
23 rotor locking arrange-ment
24 stator element (main frame)
25 rotor shaft
26 brake disk
27, 28, 29 recess
30 stator sided end
31 edges
32 pin locking element
33 connection lug
34 bore