Centering a Line in a Rotating Shaft

Abstract

The device for centering a line in a rotating hollow shaft comprises a tube, the wall of which is slotted over the entire tube length, substantially parallel to the tube axis, and which can be deformed for the temporary widening of the slot for the radial introduction of a line into the tube. Bristle tufts distributed in the longitudinal and circumferential direction are arranged on the outer side of the tube for support on the inner wall of the rotating hollow shaft. In the wind turbine having a rotor rotatably supported on a gondola around a rotor shaft formed as a hollow shaft, wherein at least one line is led from the rotor through the rotor shaft to the gondola, the line guidance in the rotor shaft is implemented as an arrangement according to the invention.

Claims

1. A device for centering a line in a rotating hollow shaft (23) having an inside surface, said device comprising: a tube (2) having a length and a wall (3) surrounding a central axis, said wall (3) having an outside surface and including a slot (4) substantially parallel with said axis and extending the entire length of the tube (2) said wall is deformable for the temporary widening of the slot (4) to allow the introduction of a line (91) in a radial direction through the slot (4) into the tube (2); and bristle tufts (5) distributed on said outside surface of the wall (3) of said tube (2), said bristle tufts (5) comprising bristles having free ends projecting away from said outside surface and distributed about a circumference and along the length of said tube (2).

2. The device of claim 1, wherein said tube (2) is elastically deformable for the temporary widening of said slot (4).

3. The device of claim 1, wherein an outside diameter (6) of the device (1) is defined by the free ends of said bristle tufts (5), said outside diameter (6) is larger than an inside diameter of the rotating hollow shaft (23).

4. The device of claim 3, wherein said outside diameter (6) is 5% to 10% greater than the inside diameter of the rotating hollow shaft (23).

5. The device of claim 1, wherein said bristle tufts (5) project from said outside surface at an angle not equal to 90 with respect to said outside surface, and said bristles are inclined away from an expected direction of movement (92).

6. The device of claim 1, wherein said bristle tufts (5) are distributed uniformly over the length or about the circumference of the tube (2).

7. The device of claim 1, wherein said wall (3) has a thickness includes at least one tapering region (9) wherein said thickness is reduced, said at least one tapering region (9) extending the length of the tube (2) and parallel with said axis.

8. The device of claim 7, wherein said at least one tapering region (9) comprises a plurality of tapering regions (9) uniformly distributed about the circumference of said tube (2).

9. The device of claim 7, wherein each of said tapering regions includes longitudinally extending edges facing the inner side of said tube (2), and said longitudinally extending edges are de-burred or defined by a radius.

10. The device of claim 1, comprising a connecting element (10) for connecting the device to an axially adjacent second said device, said connecting element (10) is provided on the outside surface or an end of said tube (2).

11. The device of claim 1, wherein the tube (2) has sections (8) free of bristle tufts (5).

12. The device of claim 1, wherein said tube (2) is extruded or injection molded from plastic and is then provided with bristle tufts (5).

13. An arrangement comprising a hollow shaft (23) and at least one line (91) guided in the hollow shaft (23) by a device of claim 1, said device surrounding said at least one line (91) and the free ends of said bristles contacting an inside surface of said hollow shaft (23).

14. The arrangement of claim 13, wherein said tube (2) has an internal diameter that is less than or equal to the diameter of the at least one line (91) guided therein.

15. The arrangement of claim 13, comprising a plurality of the devices of claim 1 arranged one after another along a length of the at least one line (91).

16. The arrangement of claim 13, wherein said hollow shaft (23) is the rotor shaft of a wind turbine (20) and the at least one line (91) extends from a rotor of the wind turbine (20) through the rotor shaft to a gondola (27) of the wind turbine (20), said at least one line (91) is guided through the rotor shaft by at least one said device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The invention will now be described by way of example by using advantageous embodiments and with reference to the appended drawings, in which:

[0030] FIG. 1 shows a first exemplary embodiment of a device according to the invention;

[0031] FIGS. 2A-2C show schematic illustrations of the use of the device from FIG. 1;

[0032] FIG. 3 shows a second exemplary embodiment of a device according to the invention;

[0033] FIG. 4 shows a schematic sectional illustration of the device from FIG. 3;

[0034] FIG. 5 shows a schematic sectional illustration of variation of the device from FIG. 4;

[0035] FIG. 6 shows a schematic sectional illustration of another variation of the device from FIG. 4; and

[0036] FIG. 7 shows a schematic sectional illustration of a wind turbine with a device according to any one of the FIGS. 1-6.

DETAILED DESCRIPTION

[0037] A first exemplary embodiment of a device 1 according to the invention is illustrated in FIG. 1.

[0038] The device 1 comprises a tube 2 of plastic, the wall 3 of which is provided over the entire tube length with a slot 4 parallel to the tube axis. The plastic is chosen to be elastic, such that the slot 4 can be deformed for the radial introduction of a line bundle 90 or an individual line 91 into the tube 2.

[0039] Arranged on the outer side of the tube 2, distributed in a regular grid in the longitudinal and circumferential direction are bristle tufts 5, which project at right angles to the outer side of the tube 2.

[0040] The longest bristles of the bristle tufts 5 define the external diameter of the device 1. This external diameter is chosen such that it is larger by 5% than the internal diameter of that hollow shaft into which the device 1 is to be inserted. Following the insertion into just this hollow shaft, the line bundle 90 is held centered by the bristle tufts 5, which rest on the inner wall of the hollow shaft.

[0041] The introduction of lines 91 or a line bundle into the device 1 according to FIG. 1 is illustrated schematically in FIGS. 2A-2C. Starting from an initial state, in which the tube 2 is not deformed and has an internal diameter 2 (FIG. 2A), the slot 4 is widened by elastic deformation of the tube wall 3 in such a way that the lines 91 laid together to form a line bundle 90 with an outer diameter 92, which is slightly greater than the internal diameter 2 of the tube 2, can be introduced into the tube 2 in the radial direction relative to the tube axis (FIG. 2B). Then, the tube 2 returns into its original shape, which means that the tube 2 encloses the line bundle 90 (FIG. 2C).

[0042] In FIG. 2C, the external diameter 6 defined by the free ends of the bristle tufts 5more accurately the respectively longest bristles thereofis also illustrated. This external diameter 6 is larger than the inner diameter 95 of the rotating hollow shaft in which the device 1 is to be introduced. The tube 2 in the configuration illustrated in FIG. 2C can be secured with cable ties 7, which are laid around the tube 2 in bristle tuft-free sections (cf. FIG. 1).

[0043] FIG. 3 shows a second exemplary embodiment of a device 1 according to the invention, which builds on the first exemplary embodiment. In the following text, only the differences from the first exemplary embodiment will therefore be explained and reference will be made below to the above explanations relating to FIGS. 1 and 2A-C.

[0044] The bristle tufts 5 in the exemplary embodiments according to FIG. 3 are no longer perpendicular with respect to the outer side of the tube 2 but are instead arranged inclined at an angle of less than 90 in the direction of the rotor axis. By means of an appropriate arrangement of the bristle tufts 5, the insertion of the device 1 into a hollow shaft in the direction indicated by arrow 92 is made easier.

[0045] Furthermore, the device 1 also has a plurality of bristle tuft-free sections 8, at which the device 1 can be severed as necessary. As a result, it is possible to reduce the length of the device 1 to a desired dimension. In just these sections 8, cable ties 7 for securing the device 1 to the line bundle 90 can also be arranged (cf. FIG. 1).

[0046] At the two ends of the tube 2, connecting elements 10 are also provided, via which the device 1 can be connected to adjacent devices 1 as illustrated. The connecting elements 9 are implemented as projections with a passage hole, into which connecting clips (not illustrated) can be inserted.

[0047] As can be seen in the sectional illustration according to FIG. 4, the wall 3 of the tube 2 has, at the point opposite the slot 4 in the circumferential direction, a tapering region 9 on the inside, which extends over the entire length the tube 2. By means of this tapering region 9, the widening of the slot 4 via elastic deformation of the tube 2 is made easier. The edges in the region of the tapering region 9 are all rounded in order to avoid damage to the lines 91 of the line bundle 90.

[0048] While the tube 2 of the first exemplary embodiment according to FIGS. 1 and 2A-C can be produced in an extrusion process, the tube of the second exemplary embodiment is an injection molding. The common feature of the two embodiments is that the bristle tufts 5 are attached to the tube 2 following fabrication of the latter. Furthermore, the tubes 2 are of such elastic plastic that the widening of the slot 4 described in conjunction with FIGS. 2A-C is possible without damage.

[0049] FIG. 5 shows a variation of the second exemplary embodiment according to FIGS. 3 and 4, where instead of a single tapering region 9, two tapering regions 9 are provided symmetrically to the median plane 4 defined by the slot 4. Furthermore, the edges defining the slot 4 are provided with radii. For securing the device 1 enclosing the line bundle 90, a number of latching elements 11 are provided along the length of the device 1.

[0050] FIG. 6 shows yet another variation of the second exemplary embodiment according to FIGS. 3 and 4. The device 1 comprises two slots 4 located at opposite sides of the device 1. Each of the slots 4 is bordered by a flange 12 that allows for screw fixing 13 the two halves of the device 1 together.

[0051] FIG. 7 shown the usage of the inventive device in a wind turbine 20. The wind turbine 20 has a rotor 21 with rotor blades 22 rotatably supported on a gondola 27 around a rotor shaft formed as a hollow shaft 23. The hollow shaft 23 passes through a gearbox 24 whose pinion shaft 25 drives a generator 26. Inside the hollow shaft 23, two inventive devices 1 are provided for centering lines 91 inside the hollow shaft 23. The lines 91 run from a slip ring arrangement 28 in the gondola 27 to pitch actuators 29 at the rotor blades 22.