Apparatus for movement along a tower structure

Abstract

A plurality of sliding rails and a frame structure comprising a plurality of frame elements configured to be arranged at least partly circumferentially around a tower structure. Each frame element is slidably connected to at least one of the sliding rails, and the frame elements and the sliding rails are interconnected to form a scissor structure. An upwardly directed lifting force applied by a hoisting mechanism at connecting points at or near positions where the frame elements are connected to the sliding rails, in combination with gravity working on the frame structure, causes the frame elements to slide along the sliding rails, thereby causing the scissor structure to contract or expand to adjust a diameter of the frame structure to an outer diameter of the tower structure having the apparatus mounted thereon.

Claims

1. A system for movement along a tower structure, comprising: an apparatus configured to be arranged at least partly circumferentially around the tower structure, the apparatus comprising: a plurality of sliding rails, and a frame structure comprising a plurality of frame elements, each frame element being slidably connected to at least one of the sliding rails, the frame elements and the sliding rails being interconnected to form a scissor structure, and a hoisting mechanism for raising and lowering one or more wires connected to the frame structure of the apparatus via connection points of at least some of the frame elements at or near positions where the frame elements are connected to the sliding rails, wherein the plurality of frame elements pivot with respect to each other at said connection points along a horizontal pivot axis, the hoisting mechanism for hoisting the apparatus along the tower structure having the apparatus mounted thereon, wherein raising and lowering the one or more wires using the hoisting mechanism, in combination with gravity working on the frame structure, causes the frame elements to slide along the sliding rails, thereby causing the scissor structure to contract and expand, respectively, to adjust a diameter of the frame structure to an outer diameter of the tower structure having the apparatus mounted thereon.

2. The system according to claim 1, wherein the frame elements are arranged in pairs, where a first frame element of a pair of frame elements has a first end fixedly connected to a first sliding rail and a second end connected slidingly to a second sliding rail, and where a second frame element of the pair of frame elements has a third end fixedly connected to the second sliding rail and a fourth end connected slidingly to the first sliding rail, and wherein the first frame element and the second frame element are pivotally connected to each other at a position arranged between the first end and second end of the first frame element and the third end and fourth end of the second frame element.

3. The system according to claim 1, wherein the frame structure defines a polygonal shape configured to surround the circumference of the tower structure.

4. The system according to claim 1, wherein the apparatus comprises treatment means for applying a surface treatment to a surface of the tower structure, and wherein the treatment means is configured for cleaning, abrasive treatment, painting and/or coating of the surface of the tower structure.

5. The system according to claim 4, wherein the treatment means comprises a plurality of nozzles arranged to spray a fluid onto the tower structure having the apparatus mounted thereon, and at least one fluid reservoir connected to the plurality of nozzles.

6. The system according to claim 5, wherein the treatment means comprises a plurality of spray confinement means arranged in pairs on opposing sides of at least some of the plurality of nozzles in order to substantially contain the fluid being sprayed from the at least some of the plurality of nozzles within a boundary defined by the spray confinement means.

7. The system according to claim 5, wherein the apparatus comprises or is connected to a fluid collecting system for collecting surplus fluid sprayed by means of the plurality of nozzles.

8. The system according to claim 1, wherein the frame structure comprises two or more subassemblies being releasably connected to each other, thereby allowing the frame structure to be assembled and disassembled.

9. The system according to claim 1, wherein the hoisting mechanism comprises a beam configured to be arranged on top of the tower structure, and a lifting apparatus operatively connected to the one or more wires.

10. The system according to claim 1, wherein the hoisting mechanism comprises a control mechanism arranged to ensure that the apparatus maintains a substantially horizontal orientation during movement along the tower structure.

11. The system according to claim 1, further comprising a remote control, wherein the remote control is configured for wired or wireless control of at least the hoisting mechanism from a position remote to the hoisting mechanism.

12. The system according to claim 1, wherein the apparatus comprises a plurality of nozzles arranged to spray a fluid onto the tower structure having the apparatus mounted thereon, and wherein the system further comprises a fluid reservoir connected to the plurality of nozzles and a fluid collecting system for collecting surplus fluid sprayed by means of the plurality of nozzles.

13. The system according to claim 12, wherein the fluid collecting system is configured to be arranged circumferentially around the tower structure.

14. The system according to claim 13, wherein the fluid collection system comprises a seal, wherein the seal is configured to conform to a surface of the tower structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will now be described in further detail with reference to the accompanying drawings in which

(2) FIG. 1 is a side view of an apparatus according to an embodiment of the invention,

(3) FIG. 2 is a side view of a wind turbine tower structure having an apparatus according to an embodiment of the invention mounted thereon in a first position along the tower structure,

(4) FIG. 3 is a side view of the a wind turbine tower structure having an apparatus according to an embodiment of the invention mounted thereon in a second position along the tower structure,

(5) FIG. 4 is a cross sectional view of the wind turbine tower structure and apparatus of FIG. 2, along the line A-A,

(6) FIG. 5 is a cross sectional view of the wind turbine tower structure and apparatus of FIG. 3, along the line B-B,

(7) FIG. 6 is a side view of a first detail of an apparatus according to an embodiment of the invention,

(8) FIG. 7 is a side view of a second detail of an apparatus according to an embodiment of the invention, and

(9) FIGS. 8a-8h illustrate sequential assembly of an apparatus according to an embodiment of the invention around a tower structure.

DETAILED DESCRIPTION OF THE DRAWINGS

(10) FIG. 1 is a side view of an apparatus 1 according to an embodiment of the invention. The apparatus 1 comprises a plurality of sliding rails 2, four of which are shown. The apparatus 1 further comprises a frame structure comprising a plurality of frame elements 3, six of which are shown. The apparatus 1 may be arranged at least partly circumferentially around a tower structure. This will be described in further detail below with reference to FIGS. 2-5 and 8a-8h.

(11) Each of the frame elements 3 has one end 4 fixedly connected to one of the sliding rails 2 and another, opposite end 5 connected slidingly to another one of the sliding rails 2. Accordingly, the ends 5 of the frame elements 3 are allowed to slide along the sliding rails 2, as indicated by arrows 6, while the ends 4 of the frame elements 3 remain in the illustrated position relative to the sliding rails 2. Furthermore, the frame elements 3 are arranged in pairs, the two frame elements 3 forming a pair being connected to the same two sliding rails 2. The frame elements 3 of a pair of frame elements 3 are further pivotally connected to each other at a pivot point 7. Accordingly, the frame elements 3 of a pair of frame elements 3 are further allowed to pivot relative to each other, about the pivot point 7. The frame elements 3 and the sliding rails 2 in combination form a scissor structure. This will be described in further detail below.

(12) The frame structure is connected to a hoisting mechanism 8, via wires 9, at connecting positions 10 being arranged near the positions where the frame elements 3 are slidingly connected to the sliding rails 2.

(13) The apparatus 1 may be operated in the following manner. When it is desired to hoist the apparatus 1 along a tower structure, i.e. to move it to a higher position along the tower structure, the hoisting mechanism 8 applies an upwardly directed lifting force to the connecting points 10. Simultaneously, gravity working on the frame structure will tend to pull the frame structure in a downwards direction. This will cause the ends 5 of the frame elements 3 to slide along the sliding rails 2 in an upwards direction, causing the frame elements 3 of each pair of frame elements 3 to pivot relative to each other. As a consequence, the scissor structure formed by the frame elements 3 and the sliding rails 2 will contract until a diameter of the frame structure matches an outer diameter of the tower structure which the apparatus 1 is moved along. In the case that the diameter of the tower structure decreases along an upwards direction, the diameter of the frame structure is thereby automatically decreased to match the outer diameter of the tower structure, as the apparatus 1 is moved upwards along the tower structure.

(14) Similarly, in the case that it is desired to lower the apparatus 1 along the tower structure, i.e. to move the apparatus to a lower position along the tower structure, the hoisting mechanism 8 will still apply an upwardly directed force to the connecting points 10 of the frame structure, while gravity working on the frame structure pulls the frame structure in a downwards direction. Accordingly, the scissor structure formed by the frame elements 3 and the sliding rails 2 is also biased towards a decreased diameter, and the diameter of the frame structure therefore also automatically matches the outer diameter of the tower structure in this case. Accordingly, the diameter of the frame structure automatically increases to match the increasing outer diameter of the tower structure, as the apparatus 1 is lowered along the tower structure.

(15) In the embodiment shown the apparatus 1 is equipped with rollers 24 that roll on the surface of the tower, as the apparatus 1 moves along the tower. The rollers 24 maintain a fixed distance between the surface of the tower and the apparatus 1. The rollers 24 apply a substantially constant force to the surface of the tower. The force depends on the weight of the apparatus 1.

(16) FIG. 2 is a side view of a wind turbine tower structure 11 having an apparatus 1 according to an embodiment of the invention mounted thereon. The tower structure 11 has an outer diameter which decreases along an upwards direction. The apparatus 1 could, e.g., be the apparatus 1 illustrated in FIG. 1.

(17) The apparatus 1 is mounted on the tower structure 11 at a first position, which is relatively close to the ground. Accordingly, the apparatus 1 is mounted on the tower structure 11 at a position where the outer diameter of the tower structure 11 is relatively large. Therefore the scissor structure formed by the frame elements 3 and the sliding rails 2 of the apparatus 1 is in an expanded position, allowing the diameter of the frame structure to adapt to the large outer diameter of the tower structure 11. It can be seen from FIG. 2 that this is obtained by allowing the slidingly connected ends of the frame elements 3 to slide to a relatively low position along the sliding rails 2.

(18) The apparatus 1 is provided with a plurality of nozzles 12, two of which are shown. The nozzles 12 are connected to a fluid reservoir 13, via a pump 14 and hoses 15. Thereby the nozzles 12 are configured to spray the fluid onto an outer surface of the tower structure 11. The fluid could, e.g., be water or a cleaning agent. In this case the apparatus 1 may be used for cleaning the outer surface of the tower structure 11. As an alternative, the nozzles 12 may be configured to spray another kind of fluid onto the outer surface of the tower structure 11, such as paint, coating or the like.

(19) A fluid collecting system 16 is mounted circumferentially around the base of the tower structure 11. The fluid collecting system 16 comprises a seal 17, which is configured to conform to the surface of the tower structure 11. Thereby a tight fit is provided between the outer surface of the tower structure 11 and the fluid collecting system 16. The fluid collecting system 16 further comprises an outer inflatable barrier 18. When the outer inflatable barrier 18 is inflated, leakage from the fluid collecting system 16 is prevented. Thus, surplus fluid sprayed onto the outer surface of the tower structure 11 by means of the nozzles 12 flows along the outer surface of the tower structure 11, and is collected in the fluid collecting system 16.

(20) The hoisting mechanism 8 comprises a beam 19 arranged on top of the wind turbine, and a number of lifting apparatuses 20, two of which are shown. The lifting apparatuses 20 could, e.g., be in the form of cranes or winches. The lifting apparatuses 20 are connected to the apparatus 1 via wires 9.

(21) An operator 21 can operate the lifting apparatuses 20, and possibly also at least the nozzles 12 of the apparatus 1, by means of a remote control 22. Accordingly, the apparatus 1 can be moved along the tower structure 11 without requiring that the operator 21 is positioned on the apparatus 1 or at the position of the lifting apparatuses 20.

(22) FIG. 3 is a side view of the wind turbine tower structure 11 and apparatus 1 of FIG. 2. However, in FIG. 3 the apparatus 1 is mounted on the tower structure 11 at a second position, which is further away from the ground and closer to the top of the tower structure 11 than the first position illustrated in FIG. 2. Accordingly, the apparatus 1 is mounted on the tower structure 11 at a position where the outer diameter of the tower structure 11 is smaller than is the case in the situation illustrated in FIG. 2. Therefore the scissor structure formed by the frame elements 3 and the sliding rails 2 of the apparatus 1 is contracted as compared to the situation illustrated in FIG. 2, allowing the diameter of the frame structure to adapt to the smaller outer diameter of the tower structure 11. It can be seen from FIG. 3 that this is obtained by allowing the slidingly connected ends of the frame elements 3 to slide to a relatively high position along the sliding rails 2.

(23) FIG. 4 is a cross sectional view of the wind turbine tower structure 11 and apparatus 1 of FIG. 2, along the line A-A, and FIG. 5 is a cross sectional view of the wind turbine tower structure 11 and apparatus 1 of FIG. 3, along the line B-B. It is clear from FIGS. 4 and 5 that the scissor structure defined by the frame elements 3 and sliding rails 2 of the apparatus 1 of FIGS. 3 and 5 is contracted as compared to the situation illustrated in FIGS. 2 and 4.

(24) FIG. 6 is a side view of a first detail of an apparatus 1 according to an embodiment of the invention. Two frame elements 3 of the frame structure are connected pivotally to each other in a pivot point. At the pivot point, a pendulum 23 is mounted. In the case that the frame structure is tilted during hoisting or lowering of the apparatus 1, the pendulum 23 will swing away from its neutral position. The pendulum 23 may be connected to a control unit for controlling operation of the lifting apparatuses of the hoisting mechanism in such a manner that the operation of the lifting apparatuses is adjusted when the pendulum 23 swings away from its neutral position. Thereby a substantially horizontal orientation of the frame structure is restored.

(25) FIG. 7 is a side view of a second detail of an apparatus 1 according to an embodiment of the invention. Two frame elements 3 of the frame structure are connected pivotally to each other in a pivot point 7. Four nozzles 12 are mounted on one of the frame elements 3. Spray confinement means in the form of spray protection brushes 24 are mounted adjacent to the nozzles 12. Thereby the fluid being sprayed by means of the nozzles 12 is contained within a boundary defined by the spray confinement means 24. Accordingly, it is ensured that the fluid being sprayed by means of the nozzles 12 is directed towards a desired portion of the outer surface of the tower structure having the apparatus 1 mounted thereon.

(26) FIGS. 8a-8h illustrate sequential assembly of an apparatus 1 according to an embodiment of the invention around a tower structure 11. In FIG. 8a only one subassembly of the apparatus 1 has been arranged adjacent to the tower structure 11. The subassembly includes a number of frame elements 3 having a nozzle 12 mounted thereon, the frame elements 3 being connected to two sliding rails 2.

(27) In FIG. 8b a second subassembly has been assembled to the first section, in the form of an additional number of frame elements 3, having a nozzle 12 mounted thereon, and an additional sliding rail 2.

(28) In FIGS. 8c-8h, additional subassemblies are sequentially added to the apparatus 1, until eight subassemblies cover the entire periphery of the tower structure 11, as illustrated in FIG. 8h. It can be seen from FIG. 8h that the frame structure of the final apparatus 1 defines an octagonal shape. This shape represents a suitable balance between a structure which follows the circular circumference of the tower structure 11 and straight sections which are easy to handle.

(29) It is an advantage of the embodiment illustrated in FIGS. 8a-8h that it is modular in the sense that it is manufactured from a number of subassemblies which can be transported and handled separately. This makes it easier to transport the apparatus 1 and to mount the apparatus 1 on a tower structure 11.