WO2011082709A1

WO2011082709A1 - Winding machine

Info

Publication number: WO2011082709A1
Application number: PCT/DK2010/050356
Authority: WO
Inventors: Anton Bech
Original assignee: Vestas Wind Systems AS
Current assignee: Vestas Wind Systems AS
Priority date: 2010-01-08
Filing date: 2010-12-22
Publication date: 2011-07-14
Anticipated expiration: 2012-07-08

Abstract

The invention relates to a winding machine for winding ribbon or filament material (203) around an elongated object (292), e.g. the spar of a wind turbine blade. According to the invention the winding machine has an opening (204,304) in a structural part which at least partly encircles the object during the winding process. The opening (204, 304) allows easy positioning o the winding machine or the object (292) since the object can pass through the opening along a radial direction, i.e. a direction perpendicular to the elongated extension of the object. The winding machine includes a carrousel which includes a movable element configured to be guided by a guiding support Accordingly, the carrousel is constructed as an open structure in contrast to a closed structure such a closed ring.

Description

WINDING MACHINE

FIELD OF THE INVENTION

The invention relates to a winding machine for winding material around an object, in particular to such a machine for winding material around elongated objects.

BACKGROUND OF THE INVENTION

Blades for wind turbine generators may be constructed from an outer airfoil which may be structurally supported by a spar, i.e. a beam, extending in the interior of the airfoil throughout the length of the blade. Due to the length of the blade, the spar may be manufactured from prefabricated sections which are joined to form the final spar.

The joining of the spar sections may be performed by winding material around the abutting spar sections, for example carbon and glass material in the form of fibres or ribbon which are impregnated with adhesives and finally cured.

It is known to use ring shaped carrousels for winding material around objects. During the winding, the object can be translated through the carrousel to form a helix shaped winding on the object. However, translation of the object is impractical for long objects, in particular for sectioned objects. Therefore, it would be desirable to improve winding machines for long objects and sectioned objects.

Furthermore, it would be desirable to improve winding based methods for joining of sectioned elongated objects.

US2003/0051795 discloses a filament winding apparatus for fabrication of composite material products based on a mechanism that rotates filaments around a non-rotating mandrel. The primary filaments in predetermined patterns tend to move on the mandrel and thus such filaments are fixed in position relative to the mandrel by over-wrapping them with secondary filaments applied over the primary filaments. The winding mechanism functions by rotating filament spools around a non-rotating mandrel rather than rotating the mandrel to pull the filaments onto the mandrel. The mandrel is axially translated through the centre of the winding mechanism or the winding mechanism is translated over a stationary mandrel which is supported in such a manner as to provide for such translation .

When objects become very long or when elongated objects are sectioned, the winding machine of US2003/0051795 becomes impractical . In particular, it may be difficult to translate sectioned elongated objects through the rotating carrousel of US2003/0051795. Accordingly, improvements relating to winding machines for elongated objects as indicated are desired . SUMMARY OF THE INVENTION

It would be advantageous to achieve improvements of methods and machines for winding material around long objects. It would also be desirable to improve methods for joining sectioned long objects. In general, the invention preferably seeks to mitigate, alleviate or eliminate one or more of the above mentioned disadvantages of winding material around long objects and/or joining of long objects by winding . In particular, it may be seen as an object of the present invention to provide a method that solves the above mentioned problems, or other problems, of the prior art. To better address one or more of these concerns, in a first aspect of the invention a winding device for winding filament or ribbon material around an elongated object is presented which comprises

- a moveable element,

- one or more spools for accommodating the winding material and attached to the moveable element,

- a guiding support arranged to guide the moveable element along a closed trajectory having a radial direction and a perpendicular axial direction,

wherein the moveable element and/or the guiding support has a passage to enable relative movement between the winding device and the elongated object in the radial direction between a configuration where the elongated object is circumscribed by the closed trajectory and a configuration where the elongated object is located outside the closed trajectory, and

- a closure structure formed to fit the passage of the moveable element. Since the moveable element, alternatively or additionally the guiding support, has a passage, it is possible to locate the object in a winding position, i.e. a position enabling winding of some material around a section of the object, simply by moving the winding device or the object in a direction perpendicular to the elongated direction of the object to a position where the elongated object becomes circumscribed by the closed guiding trajectory. Similarly, due to the passage, it is possible to oppositely move the winding device or the object in the traverse directions so as to free the object from the winding device, e.g. after the winding has been completed.

Disengagement of the object from the winding device by simply moving either of them in a traverse direction may be particularly advantageous when the winding device is used for joining spar sections of a spar for wind turbine blades. That is, after the sections have been joined, the spar and the winding device can be separated by moving e.g . the winding device in a direction perpendicular to the elongate direction of the spar through the passage provided in the moveable element and/or the guiding support.

Without the passage it would be necessary to move the winding device from an end of the elongated object to a given position before winding starts. Similarly it would be necessary to move the winding device from the winding position to an end to disengage the winding device from the elongated object after winding has been completed. The translation of the winding device along the elongated object is further complicated when the spar or spar sections are supported by floor supports which have to be removed to allow passage of the winding device.

Thus, the passage in the guiding support of the moveable element

advantageously improves winding of long objects and, in particular, joining of long objects by winding material around abutting ends.

In an embodiment the moveable element or the guiding support is formed as an arc shaped structure having an opening between the ends of the arc forming the passage towards the center of the closed trajectory. In general the arc shaped structure may be any open structure having an interior capable of accommodating a section of the object. In an embodiment the winding device comprises a closure structure formed to fit the passage by connecting the ends of the guiding support, i.e. instead of closing the passage of the moveable element the passage of the guiding support may be closed .

The closure structure advantageously stabilizes the open structure whether it is used for closing the moveable element or the guiding support. Furthermore, the closure may improve smooth rotation of the movable element when the closure has a shape or curvature corresponding to the moveable element or the guiding support so as to form a continuous surface, e.g . a continuous inner or outer periphery.

Thus, in an embodiment the closure structure has a curvature corresponding to the curvature of the arc shaped structure so as to form a closed ring when the closure structure is positioned relative to the opening of the arc shaped structure, for example inserted into the opening of the arc shaped structure.

In another embodiment the guiding support comprises a driver for driving the movable element along the closed trajectory. Whereas one driver may be sufficient, use of a plurality of drivers is also feasible.

In an embodiment the guiding support comprises rollers angularly distributed along at least a section of the closed trajectory to contact an inner and/or outer circumference of an arc shaped body of the moveable element. The rollers may be provided for achieving smooth rotation of the movable element. Additionally, the rollers may be configured to stabilize the movable element in an axial direction, i.e. to avoid or minimize tilt of the movable element. In an embodiment at least one of the rollers is driven, e.g . by an electromotor to drive the rotation of the movable element.

In an embodiment the winding device comprises a transportation device for enabling transport of the winding device in the axial direction of the closed trajectory. In an embodiment the winding device comprises a transportation device for enabling transport of the winding device in the radial direction of the closed trajectory.

It is understood that the transportation device may be configured to enable transport of the winding device both in the radial and the axial directions, e.g. by wheels arranged to roll on a floor, which wheels may be oriented to enable transport in the radial and axial directions.

In a related embodiment the transportation device is additionally configured to enable transport of the winding device in a radial direction of the ring shaped structure parallel with a floor surface. Accordingly, the transportation device may be used for positioning of the winding device before winding starts and/or for removal of the winding device after the winding has been completed by moving the winding device in a radial direction. Additionally or alternatively, the transportation device may be used for translating the winding device along the elongated object during winding by moving the winding device in the axial direction.

In a second aspect the invention relates to a method for winding filament or ribbon material around a stationary elongated object, the method comprising

- providing a moveable element, where the moveable element has one or more spools attached for accommodating the winding material,

- providing a guiding support arranged to guide the moveable element along a closed trajectory having a radial direction and a perpendicular axial direction,

- obtaining relative movement between the guiding support and the elongated object in the radial direction between a configuration where the elongated object is circumscribed by the closed trajectory and a configuration where the elongated object is located outside the closed trajectory via a passage formed by the moveable element and/or the guiding support, and

- closing the passage of the moveable element with a closure structure. Accordingly, a method is provided for winding filament or ribbon material around a stationary elongated object using the winding device according to an

embodiment of the invention by performing the steps acoording to this second aspect.

In an embodiment of the method, during the relative passage of the winding device and the elongated object, the longitudinal direction of the elongated object is parallel, or substantially parallel, with the axial direction of the closed

trajectory.

In an embodiment of the method, a first stationary elongated object is joined to a second elongated object by winding the filament or ribbon shaped material around the first object and the second object. Since the winding device is provided with a passage to enable passage of the elongated object, the winding device may be particularly advantageous for joining abutting ends of the sectioned elongated objects.

In an embodiment of the first or second aspects the elongated object is a spar of a wind turbine blade.

A third aspect of the invention relates to a winding device for winding filament or ribbon material around an elongated object. The device comprises

- a spool for accommodating the winding material,

- a first arm engageable with the spool and configured to move the spool from a first location to a second location along a first trajectory partly circumscribing the elongated object,

- providing a second arm engageable with the spool and configured to move the spool from the second location to the first location along a second trajectory partly circumscribing the elongated object,

where the combined first and second trajectories fully circumscribe the elongated object.

A fourth aspect of the invention relates to a method for joining a first stationary elongated object to a second elongated object by winding filament or ribbon shaped material around the first object and the second object. The method comprises

- moving a spool accommodating the winding material using a first arm from a first location to a second location along a first trajectory partly circumscribing the first and second elongated objects,

- moving the spool using a second arm from the second location to the first location along a second trajectory partly circumscribing the elongated object, so that the first and second trajectories in combination fully circumscribe the first and second elongated objects.

Accordingly, the third and fourth aspects are based on the same or corresponding inventive technical concepts as the first and second aspects. That is, the third and fourth aspects have a passage in the form of an open structure provided by the separate first and second arms to allow easy positioning of the object relative to the winding position. Correspondingly, the first and second aspects have an equivalent passage in the form of an opening provided in the guiding support and/or the movable element.

In summary, the invention relates to a winding device for winding ribbon or filament material around an elongated object, e.g. the spar of a wind turbine blade. According to the invention the winding device has an opening in a structural part which at least partly encircles the object during the winding process. The opening allows easy positioning of the winding device or the object since the object can pass through the opening along a radial direction, i.e. a direction perpendicular to the elongated extension of the object. The winding device includes a carrousel which includes a movable element configured to be guided by a guiding support. Accordingly, the carrousel is constructed as an open structure in contrast to a closed structure such as a closed ring. In general the various aspects of the invention may be combined and coupled in any way possible within the scope of the invention. These and other aspects, features and/or advantages of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. BRIEF DESCRIPTION OF FIGURES

Embodiments of the invention will be described, by way of example only, with reference to the drawings, in which Fig. 1A shows a wind turbine blade with a strengthening spar,

Fig. IB shows a sectioned elongated spar for a wind turbine blade,

Fig. 1C shows a cross sectional view of the spar and a winding carrousel,

Fig. 2A shows a winding device having an arc shaped carrousel for rotating spools around a cross sectional section of an elongated object,

Fig. 2B shows a side view of the winding device,

Fig. 3 shows a winding device having an arc shaped guide for guiding a spool on a guided object around a cross sectional section of an elongated object,

Figs. 4A-D illustrate different configurations of winding devices,

Fig. 5 illustrates an alternative winding device.

DESCRIPTION OF EMBODIMENTS

Fig. 1A shows a blade 101 for a wind turbine generator. The blade 101 is strengthened by a spar 100 which is fixed to the interior of the outer shells of the blade 101. The spar is generally a hollow elongated structure made from metal, composite material or similar.

The blade 101 and the spar 100 may have a length greater than 30 or 50 meters and possibly greater than 100 meters. Therefore, it may be advantageous to manufacture the spar 100 in shorter sections 100a and 100b as illustrated in Fig. IB. Before the spar 100 is fixed to the shells of the blade 101, the sections need to be joined . As illustrated in Fig. IB, the spar sections may be joined by a sleeve 110 fixed to the outer surfaces of abutting ends of the spar sections.

Practically, the spar sections may be joined by winding material around the outer periphery of abutting spar ends to form a sleeve 110. The winding material may include glass and carbon material in the form of yarn, filament, tape and ribbon structures. In order to obtain a strong joint, several layers of winding material, preferably different materials, may be wound around the ends of the spar sections 100a, 100b. Before the spar sections 100a, 100b can be joined, they need to be aligned accurately relative to each other. Due to the length and stiffness of the spars they need to be supported by a number of spar supports 102 which need to be placed sufficiently close to limit bending of the spar sections.

Fig. 1C shows a carrousel 100 of a known winding machine. The carrousel is formed as a closed ring, which circumscribes the spar 100 or the abutting spar sections (Fig. 1C shows a cross sectional view of the spar perpendicular to the elongated direction). By rotating the carrousel, winding material 191 is wound around the spar 100. Due to the design of the carrousel as a ring shaped structure, the winding device needs to be positioned from one of the ends of the spar sections and merely moved along the spar until the correct position is achieved. However, the supports 102 hinders free movement of the winding device and, therefore, one or more supports 102 must be removed and relocated during the movement of the winding device along the elongated length of the spar.

Fig. 2A shows an embodiment of a winding device 200 for winding filament or ribbon material around elongated objects, for example for joining spar sections 100a, 100b. The winding device 200 comprises a moveable element 201 and one or more spools 202 attached to the moveable element. The spools accommodate the winding material 203 which has been wound onto the spools.

Generally the spool 202 is a holder for accommodating the winding material and configured to be rotatably connected to the moveable element 201 to enable the winding material to be un-wound from the holder. For example, the winding material may have been wound onto a simple hollow cylinder which fits onto a rotatable rod protruding from the face of the moveable element 201. Accordingly, winding material 203 can be wound around the periphery of the object 100 by attaching an end of the winding material to the object and rotating the moveable element 201 around the object so that the winding material 203 will be un-wound from the spools 202. Instead of rotating the moveable element 201, the elongated object 100 may be rotated around its axial axis 292 (pointing into the paper). In order to wind the winding material 203 along the longitudinal direction of the object 100, either the winding device 200 or the object 100 may be translated along the longitudinal axis 292.

However, for the purpose of joining sections of abutting elongating objects it is preferred to rotate and translate the winding device 200 while keeping the object stationary.

In the embodiment in Fig. 2A the moveable element is a ring or arc shaped structure 201 forming a face with a circular opening. The side of the structure 201 has an opening 204 which forms a passage into an interior of the ring structure. The opening 204 enables passage of the elongated object 100, e.g. a spar section 100a into the interior of the ring or out from the ring. Accordingly, the elongated object 100 can be brought into the interior of the winding device 200 prior to starting the winding process, and can be brought out from the winding device after the winding process simply by displacing the winding device or the elongated object along a radial axis 291 of the of ring shaped structure 201. Accordingly, since the ring shaped structure 201 does not form a closed ring, it is not necessary to displace the winding device 200 or the elongated object 100 along the longitudinal axis 292, i.e. the elongated direction of the object 100, in order to bring the object into the interior or out from the interior of the circular structure.

In Fig. 2A the ring shaped structure 201 is rotatably supported by rollers 220 comprising two rollers 221-222 arranged to contact the outer periphery and two rollers 223-224 supporting the inner periphery. Accordingly, independently of the angular position of the arc-shaped ring or C-ring 201, the inner or outer periphery is always supported by at least two rollers 220, either the exterior rollers 221- 222, the interior rollers 223-224, or a combination of exterior and interior rollers. By selecting the length between neighbouring rollers 220 to be smaller than the corresponding gap of the opening 204 it is ensured that the ring 201 is always supported by three rollers 220 when a total of four rollers is used. Thus, generally the distance between rollers 220 and the number of rollers can be adapted to the gap of the opening 204 so that the opening can make a full rotation along a closed circle or trajectory without causing significant linear displacements of the moveable element 201. In general one or more rollers 220 distributed angularly to contact an inner periphery, an outer periphery or both inner and outer peripheries of the ring shaped structure 201 may be used . Accordingly, application of two rollers 221- 222 arranged to contact the outer periphery may be sufficient to establish stable rotation of the ring shaped structure 201.

As will be clear from alternative embodiments described below, the rollers 220 embod ies a g uid ing support 220 having the function of guid ing the moveable element 201 along a closed trajectory. The outermost rollers 221-222 arranged along the outer periphery of the moveable element 201 form an outer guiding support and the inmost rollers 223-224 form an inner guiding support. The closed guiding trajectory is preferably a circular trajectory, but other closed guiding trajectories, e.g . elliptic, may also be beneficial under certain conditions. It is understood that the closed guiding trajectory generally comprises continuous trajectories which are formed by rotating the movable element around the object 100 by at least 360 deg rees. In this context an end less guiding trajectory like a helix is also understood as a closed guiding trajectory.

Fig . 2A shows that the moveable element 201 may be carried by a transportation device 230, for example a trolley. The movable element 201 may be rotatably supported by the trolley 230 via exterior rollers 221-222 fixed to the trolley. The trolley 230 is moveable in the axial d irection 292 via wheels 231 or similar transportation means to enable translation of the wind ing device 200 relative to the elongated direction of the object 100 during the winding process. Additionally, the trolley 230 may be moveable along the radial axis 291 to enable positioning of the object 100 interior or exterior to a circle circumscribing the rollers 220 or the moveable element 201. Motion of the trolley 230 in the radial d irection 291 may be enabled by wheels 231 which are hinged around a vertical direction .

Alternatively, separate wheels or transportation means may be provided for transportation along the respective axial 292 and rad ial 291 directions. The trolley may be placed on a floor surface of the manufacturing facilities.

The moveable element 201 may be rotated along a trajectory given by the position of the rollers 220 by a driver 240, for example an electro-motor. The driver may be integ rated with a roller 220 to form a driven roller capable of rotating the moveable element 201 via contact to the inner or outer periphery. One or more of the rollers 220 may function as a driver 240. The moveable element 201 may be driven by other driving means, for example a pinion interacting with a gear wheel arranged with the inner or outer periphery of the arc shaped element 201. In order to obtain continuous driving of the moveable element 201, two or more drivers 240 may be used so that at least one of the drivers is always in contact with the moveable element 201, i.e. when one or more drivers are not in contact with the moveable element 201 due to the opening 204, other drivers will be in contact. The opening 204 may be closed by a closure structure 214 as illustrated in Fig. 2A. The closure structure 214 may be formed to fit to the opening of the C-ring 201 by connecting the ends of the C-ring.

In an embodiment the closure structure 214 has a curvature equal to or corresponding to the curvature of the inner or outer periphery of the ring shaped structure so as to form a closed ring when the closure structure is inserted into the opening of the ring shaped structure. Thus, when the moveable element 201 is closed by a closure structure 214 to form a circular outer periphery, the moveable element 201 can be supported by only two rollers 221-222 located below the centre axis 292 to contact the outer periphery or two roller 223-224 located above the centre axis 292 to contact the inner periphery.

Thus, the closure structure may function both to stiffen the moveable element and to establish a continuous surface on the outer and/or inner periphery of the closed moveable element 201. Since the movable element 201 does not need to be closed in order to rotate, the closure element 214 may simply be a structure, e.g . a rod, connecting the ends of the C-ring 214 in order to stiffen the open shaped structure 201. In case the closure structure 214 is used to establish a continuous surface to support a guiding support 220, e.g . rollers 220, or constitute a guiding support in itself, the closure structure 214 may generally be an arc shaped beam, e.g. an arc of a circle.

Fig. 2B shows a side view of the winding device 200. In order to avoid tilting of the moveable element 201 it must be stabilized. The moveable element 201 may be sufficiently stabilized by ensuring that at least three rollers 220 are always in contact with the inner and/or outer peripheries. In a preferred embodiment four rollers are evenly distributed to contact the outer periphery, and a closure structure 214 is used to ensure continuous contact with all rollers to obtain smooth rotation of the moveable element. The tilting stability of the moveable element 201 may alternatively be obtained or improved by use of very wide rollers 220. Accordingly, if the rollers 220 are sufficiently long, e.g. 1 m along their axis, it may be sufficient to support the moveable element 201 by two rollers 221-222 arranged to contact the outer periphery below the center 292.

Additionally or alternatively, rollers 220 may be provided with flanges 225 arranged in contact with or slightly separated from the faces 227 of the moving element 201 so as to avoid tilting . As another means for stabilizing the moving element 201 with respect to tilting, radially oriented rollers 226 may alternatively or additionally be arranged to contact the faces 227 in a radial direction. Fig. 3 shows an alternative winding device 300 where the guiding support 220 is an arc shaped structure or C-shaped structure having an opening 304 forming a passage along the radial axis 214 into the interior of the closed guiding trajectory of the guiding support 220. In Fig. 3 the moveable element 201 subtends an angle which is less than 180 degrees and, therefore, represents no obstacle for passage of the object 100 through the closed guiding trajectory. The moveable element is provided with rollers 301,302 rotatably fixed to the moveable element. The rollers 301 are in a constrained engagement with the guiding support 220 which constrains the rollers 301 to move along a closed trajectory determined by the guiding support 220. Thus, the engagement ensures that the moveable element does not fall down due to the action of gravity when it is located on top of the guiding support. For example, the engagement may be formed as a two elongated notches, i.e. grooves, forming rails in facing flanges of the guiding support 301 along the periphery of the C-shaped flanges. The notches match the rollers 301 so that moveable element 201 can move along the closed trajectory. To ensure that the moveable element 201 does not displace radially, i.e. fall down, when the movable element is located at the bottom of the guiding support 220, additional rollers 302 rotatably fixed to the moveable element 201 and arranged to contact the inner periphery of the guiding support may be provided. One or more of the rollers 301 may be driven rollers corresponding to roller 240 of Fig. 2A.

The gap of the opening 304 or the arc length of the opening 304 along the inner periphery may be selected to be shorter than the distance or arc length between the outermost rollers 301, and at least three rollers 301 should be arrange along each rail notch, to enable the moveable element 201 to pass the opening.

Alternatively, a closure structure 391 provided with notch shaped rails may be provided and inserted into the opening 304 to enable continuous contact between rollers 301 and the guiding support 220.

Reference signs and depictions of Fig. 3 which are identical or equivalent with reference signs or equivalent depictions of Fig . 2A are functionally equivalent and, therefore, a detailed description is omitted for the embodiment of Fig. 3.

Figs. 4A-D show schematic illustrations of differently configured winding devices 401-404. Fig. 4A illustrates a winding device 411 comprising a moveable element 201 guided by a guiding support 220 having a radial axis 214 and an axial axis 292. The guiding support has a passage 404 to enable relative movement between the winding device 200,300,411 and the elongated object 100 in the radial direction 214 between a first configuration where the elongated object - oriented along the axial axis 292 - is circumscribed by the guiding trajectory of the guiding support, and a second configuration where the elongated object is located outside the guiding trajectory.

The guiding support 220 subtends an angle greater than 180 degrees (relative to its center point), whereas the moving element 201 subtends and angle less than 180 degrees (relative to the centre point) and, therefore, the guiding support is provided with a passage 404 sufficiently large to allow passage of the object 100. Alternatively, both the guiding support 220 and the moveable element 201 may subtend an angle greater than 180 degrees in which case both the guiding support and the moveable element have a passage 404. When the moveable element 201 has a sufficiently open structure, e.g. when it subtends an angle less than 180 degrees, a specific passage construction may not be required to enable relative passage of the object 100. The guiding support 220 may be embodied by a groove shaped rail arranged along an open trajectory, e.g . a C-shaped trajectory, to enable guiding of rollers 301,302 of the moveable element 201 along a closed trajectory, e.g. an O-shaped trajectory. Alternatively, the guiding support 220 may be embodied by rollers 220, as may be particularly advantageous when the moveable element 201 subtends an angle greater than 180 degrees.

Fig. 4B shows a winding device 412 capable of guiding the moveable element 201 along a closed trajectory similarly to the winding device 411. The moveable element 201 here subtends an angle greater than 180 degrees and, therefore, has a passage 404. The guiding support 220 subtends an angle less than 180 degrees and may be embodied by two or more rollers or other guiding means arranged to contact the outer periphery of the moveable element 201. When the guiding support 220 has a sufficiently open structure, e.g. when it subtends an angle less than 180 degrees, a specific passage construction may not be required to enable relative passage of the object 100. Since the moveable element 201 subtends an angle greater than 180 degrees relative to a center point, it is possible to support the moveable element with only two rollers 220, for example rollers 221-222 as illustrated in Fig. 2A. It is understood that when the movable element 201, the guiding support 220, or both subtend an angle less than 180 degrees, the reciprocal opening which may subtend an angle greater than 180 degrees also represents a passage 404 embodied by the open structure. Clearly, when the movable element or the guiding support subtends only an angle of e.g. 30 degrees, the structure is an open structure which inherently has a passage.

Fig . 4C shows an alternative embodiment of a guiding device 413 comprising a moveable element 201 guided by an outer guiding support 220a and an inner guiding support 220b. The outer and inner guiding supports 220a, 220b subtend an angle greater than 180 degrees (relative to their center points), whereas the moving element 201 subtends and angle less than 180 degrees (relative to its centre point). Accordingly, the outer and inner guiding supports are provided with respective passages 404a, 404b having sufficiently large openings to allow passage of the object 100. The inner and outer guiding supports 220a, 220b may be configured as rails or rollers as described in embodiments of Fig . 2A and Fig . 3.

Fig . 4D shows an embodiment of a winding device 414 corresponding to the winding device of Fig . 2A. Winding device 414 differs from winding device 413 by having outer and inner guiding supports 220a, 220b subtending angles smaller than 180 degrees, and a moving element 201 subtending an angle greater than 180 degrees. Accordingly, to provide clearance for the elongated object 100, the moving element 201 is provided with an opening 404. For example, each of the outer and inner guiding supports 220a, 220b may be constituted by two or more rollers 220.

Optionally, any of the winding devices 411-414 may have a closure structure matching the openings 404, 404a, 404b.

The guiding support 220 need not be formed as a continuous rail or a continuous sequence of rollers 221-224, but may be formed as a plurality of rail sections or a plurality of sequences of rollers distributed along an open trajectory, for example a C-shaped trajectory, to enable movement of the moveable element 201 along a closed trajectory, e.g . a circular trajectory. In general, both the moveable element 201 and the guiding support 220 may have passages 404. Alternatively, the moveable element 201 may have a passage 404 and the guiding support may be constructed from rollers 221-224 to enable relative movement between the winding device and the elongated object 100. As another alternative, the guiding support 220 may have a passage 404 and the moveable element 201 may be constructed as small moveable element as illustrated in Fig . 3 to enable relative movement between the winding device and the elongated object 100.

The passage 404 may be closable via a closure structure 214,391 formed to fit the passage. The passage 404 may be formed as an opening formed for example in a circle- shaped moveable element and/or a circle-shaped guiding support. Relative to the centre point of the moveable element or the guiding support the passage 404 may subtend an angle less than 180 degrees, for example an angle less than 90 degrees, such as an angle less than 45 degrees, for example an angle in the range from 5 to 40 degrees to enable relative passage of the object 100 through the passage.

Fig. 5A shows an alternative winding machine or device 500 for winding material 203 around an elongated object 100, for example in order to join abutting ends of spar sections 100a, 110b. The winding device 500 comprises a spool 202 for accommodating the winding material and first and second arms 502a, 502b which are engageable with the spool 202. The first and second arms may be operated by robots 501. The first arm is configured to connect to the spool 202 and to move the spool from a first location as shown in Fig. 5A to a second location as shown in Fig. 5B. The second arm is also configured to connect to the spool 202 and to move the spool 202 from the second location as shown in Fig. 5B back to the first location as shown in Fig. 5C. The first arm is able to connect to the spool when the spool is located in the first position and to move the spool to the second position again. Accordingly, by operating the first and second arms 502a, 502b as described above, it is possible to move the spool along a trajectory which circumscribes the elongated object around a cross sectional slice substantially perpendicular to the longitudinal direction, i.e. the axial direction 292. In other words, the first arm 502a is capable of moving the spool along a first trajectory partly circumscribing the object, and the second arm 502b is capable of moving the spool around a second complementary trajectory partly circumscribing the object so that the combination of the first and second trajectories gives a closed trajectory which fully circumscribes the object 100. The winding device 500 is similar to the winding devices 200, 300, 411-414 in that all devices enable an elongated object 100 to be located at a position for winding material around it by moving the winding device or the object in a direction being merely perpendicular to the longitudinal direction of the elongated object. That is, the object 100 may simply by moved over one of the first or second arms 502a, 502b and the robot device 501 to locate the object at the correct position. Thus, all winding devices are based on the same common inventive concept in terms of the opening 404 or the open two-part structure of the winding device 500 which creates a space between the arms 502a, 502b which is accessible for the object 100 in the same way as the interior of the guiding support 220 or the ring shaped structure 201 is accessible via the opening 404, 404a, 404b.

While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Claims

1. A winding device for winding filament or ribbon material around an elongated object, the device comprising

- a moveable element,

- a closure structure formed to fit the passage of the moveable element.

2. A winding device according to claim 1, where the moveable element or the guiding support is formed as an arc shaped structure having an opening between the ends of the arc forming the passage towards the center of the closed trajectory.

3. A winding device according to claim 1 or 2, comprising a closure structure formed to fit the passage by connecting ends of the guiding support.

4. A winding device according to claim 1 or 3, where the closure structure has a curvature corresponding to the curvature of the arc shaped structure so as to form a closed ring when the closure structure is positioned relative to the opening of the arc shaped structure.

5. A winding device according to any of the preceding claims, where the guiding support comprises a driver for driving the movable element along the closed trajectory.

6. A winding device according to any of the preceding claims, where the guid support comprises rollers angularly distributed along at least a section of the closed trajectory to contact an inner and/or outer circumference of an arc shaped body of the moveable element.

7. A winding device according to claim 6, where at least one of the rollers is driven.

8. A winding device according to any of the preceding claims, further comprising a transportation device for enabling transport of the winding device in the axial direction of the closed trajectory.

9. A winding device according to any of claims 1-7, further comprising a transportation device for enabling transport of the winding device in the radial direction of the closed trajectory.

10. A method for winding filament or ribbon material around a stationary elongated object, the method comprising

- closing the passage of the moveable element with a closure structure.

11. A method according to claim 10, where during the relative passage of the winding device and the elongated object, the longitudinal direction of the elongated object is parallel, or substantially parallel, with the axial direction of the closed trajectory.

12. A method according to claim 10, for joining a first stationary elongated object to a second elongated object by winding the filament or ribbon shaped material around the first object and the second object.

13. A method according to any of the preceding claims, where the elongated object is a spar of a wind turbine blade.

14. A winding device for winding filament or ribbon material around an elongated object, the device comprising

- a spool for accommodating the winding material,

15. A method for joining a first stationary elongated object to a second elongated object by winding filament or ribbon shaped material around the first object and the second object, the method comprising

- moving a spool accommodating the winding material using a first arm from a first location to a second location along a first trajectory partly circumscribing the elongated first and second objects,