METHOD FOR MANUFACTURING PREFORMS FOR A WIND TURBINE BLADE, MANUFACTURING ARRANGEMENT FOR MANUFACTURING PREFORMS FOR A WIND TURBINE BLADE, AND MOULD FOR A MANUFACTURING ARRANGEMENT

Abstract

A method for manufacturing preforms for a wind turbine blade is provided, with the steps: providing a mold p and arranging a preform building material p in a transferable mold element removably arranged on a mold carrier, fixating the preform building material in the mold element, removing the mold element with the fixed preform building material from the mold carrier and transferring it into a heating means, heating the preform building material for producing the preform, removing the mold element with the preform from the heating means and cooling the preform.

Claims

1. A method for manufacturing preforms for a wind turbine blade, the method comprising: providing a mold and arranging a preform building material on a transferable mold element removably arranged on a mold carrier; fixating the preform building material on the transferable mold element; removing the transferable mold element with the fixated preform building material from the mold carrier and transferring into a heating means; heating the preform building material for producing the preform; and removing the transferable mold element with the preform from the heating means and cooling the preform.

2. The method according to claim 1, wherein a mold is used comprising a mold carrier with a removable stiff tray-like mold element providing a mold surface on which the building material is arranged.

3. The method according to claim 1, wherein the transferable mold elements with the fixated preform building material is transferred from the mold carrier to a, mold transport means and either stored in the mold transport means until transported with the mold transport means to the heating means or directly transported with the mold transport means to the heating means.

4. The method according to claim 3, wherein the mold transport means moves from a first mold carrier for receiving a first mold element to one or more further mold carriers for receiving one or more further mold elements.

5. The method according claim 3, wherein the mold transport means with one or more mold elements moves into the heating means, or that one or more mold elements are moved from the mold transport means into the heating means.

6. The method according to claim 1, wherein after the heating one or more transferable mold elements are removed from the heating means and cooled in ambient air, or are moved into a cooling means.

7. The method according to claim 6, wherein a transport means comprising the one or more transferable mold elements is transferred into the cooling means, or that the one or more transferable mold elements itself are transferred from the heating means onto a transport means, wherein the transport means remains in or moves into ambient air for cooling, or wherein the transport means moves to the cooling means, wherein either the one or more mold elements are transferred into the cooling means or the transport means moves into the cooling means, or the one or more mold elements itself are directly transferred from the heating means into the cooling means.

8. The method according to claim 1, wherein the fixating of the preform building material on the transferable mold element is performed by applying a vacuum, wherein the vacuum is released at an earliest after the heating of the preform building material.

9. A manufacturing arrangement for manufacturing preforms for a wind turbine blade, comprising: one or more molds each comprising a mold carrier and one or more mold elements each configured to fixedly receive preform building material and removably arrangeable on the mold carrier; and a heating means configured to receive at least one of the mold elements, with the preform building material removed from the mold carrier.

10. The manufacturing arrangement according to claim 9, wherein each mold element is a stiff tray-like mold element providing a mold surface configured to receive the preform building material with the mold carrier comprising mold element receiving means.

11. The manufacturing arrangement according to claim 9, wherein at least one mold element transport means configured to receive the one or more mold elements with the fixated preform building material for transferring the one or more mold elements to the heating means is provided.

12. The manufacturing arrangement according to claim 9, wherein the heating means is configured to receive the one or more mold elements itself or to receive the transport means comprising one or more mold elements.

13. The manufacturing arrangement according to claim 9, wherein a cooling means is provided configured to receive the one or more mold elements with the heated preforms for cooling them.

14. The manufacturing arrangement according to claim 13, wherein the cooling means is configured to receive the one or more mold elements itself or to receive a transport means comprising the one or more mold elements.

15. The manufacturing arrangement according to claim 14, wherein the transport means is the means previously positioned in the heating means or is a further transport means configured to receive the one or more mold elements from the heating means.

16. The manufacturing arrangement according to claim 11, wherein the transport means and/or the heating means and/or the cooling means is configured to receive several mold elements itself, wherein the transport means and/or the heating means and/or the cooling means comprises vertically movable mold element receiving means for vertically stacking the several mold elements.

17. The manufacturing arrangement according to claim 11, wherein transfer means for transferring a mold element from the mold carrier to a transport means and/or from the transport means to the heating means and/or from the heating means to a further transport means or a cooling means or from the further transport means to the cooling means are provided.

18. The manufacturing arrangement according to claim 17, wherein the transfer means comprise pushing means arranged at the mold and/or at the transport means, and/or pulling means arranged at the transport means and/or at the heating means, and/or roller elements arranged at the mold and/or the transport means bearing the mold element.

19. A mold for a manufacturing arrangement according to claim 9, wherein a mold carrier and at least one interchangeable mold element, which mold element is a stiff tray-like mold element providing a mold surface configured to receive the preform building material, wherein the mold carrier comprises mold element receiving means.

20. The mold according to claim 19, wherein it comprises a transfer means for moving the mold element from the mold carrier, which transfer means comprises a pushing means and/or rolling elements arranged at the mold carrier.

Description

BRIEF DESCRIPTION

[0060] Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein:

[0061] FIG. 1 is a principle illustration of an inventive mold of a first embodiment:

[0062] FIG. 2 is a principle illustration of an inventive mold with a transport means for receiving mold elements:

[0063] FIG. 3 is a principle illustration of a manufacturing arrangement:

[0064] FIG. 4 is a principle illustration of a second alternative for transferring the mold elements into the heating means and into the cooling means:

[0065] FIG. 5 is a principle illustration of a third alternative for transferring the mold elements into the heating means and into the cooling means:

[0066] FIG. 6 is a principle illustration of a fourth alternative for transferring the mold elements into the heating means and into the cooling means; and

[0067] FIG. 7 is a principle illustration of a manufacturing arrangement of a second embodiment.

DETAILED DESCRIPTION

[0068] FIG. 1 shows a principle illustration of a mold 1 for manufacturing a preform for a wind turbine blade. The mold 1 comprises a mold carrier 2, to which a removable or interchangeable mold element 3 is attached. The mold carrier 2 comprises respective receiving elements 4, for example longitudinal rails or beams or the like, on which the mold element 3 rests. It may be fixed thereto by respective locking elements, which are released when the mold element 3 shall be removed.

[0069] The mold element 3 comprises a tray-like recess 5 with a mold surface 6, on which building material 7 for building the preform is arranged. The building material 7 comprises fiber material like fiber mats made of glass or carbon fibers, and a binding agent usually in powder or granular form. A liquid or hot melt binder may however also be used. The building material 7 is arranged in the respective order respectively the needed amounts, wherein the building material 7 obviously follows the tray-like form of the mold surface 6.

[0070] After arranging all the building material on the surface 6, a vacuum cover 8 is arranged which overlays the building material 7 and extends also onto the surface 6 of the mold element 3, as FIG. 1 shows. The mold carrier is equipped with a vacuum fixation means 9 comprising a vacuum pump and respective hoses or the like with valves allowing to couple and decouple the means 9 to the mold element 3, allowing to generate a vacuum between the mold element 3 and the vacuum cover 8 in order to evacuate the space between them, where the building material 7 is arranged. This evacuation or vacuum fixation fixes the building material 7 very tightly to the mold element 3.

[0071] The mold element 3 itself is a rigid plate-like element, which is made from a respective stiff plate for example made of a metal such as steel, aluminium or the like or a plastic that is heat resistant and form stable during the heating process that will follow. This e.g., steel or aluminium plate is shaped accordingly in order to prepare the tray-like or convex mold surface 6.

[0072] As mentioned, the mold element 3 is removable from the mold carrier 2. After vacuum fixation of the building material 7, it is possible to remove the mold element 3 with the fixed building material 7 and the vacuum cover 8 after decoupling it from the vacuum fixation means 9, while the vacuum is maintained between the mold element 3 and the vacuum cover 8, so that also the fixation of the building material is maintained. The mold element 3 can now be moved to a heating means for further processing. Solely, the mold carrier 3 remains in place and may be equipped with another new and clean mold element 3, on which immediately after removal of the previous mold element 3 a new building material 7 may be arranged etc.

[0073] The first embodiment according to FIG. 1, as mentioned, comprises a stiff and form stable, plate-like mold element 3, which is removably arranged on top of the mold carrier 2, e.g. simply by lowering it on the carrier 2 with a lifting means or by pushing it on the mold carrier 2 with a transport means or by hand. As the mold element 3 itself is stiff, the handling is easy, no form or shape change occurs during the handling and further processing.

[0074] FIG. 2 shows the inventive mold 1 according to FIG. 1. The mold element 3 with the vacuum-fixed building material is already partially moved from the mold carrier 2. The receiving means 4 are equipped with respective transfer means 14 here in form of the respective roller elements 15, on which the mold element 3 rolls and can easily be pushed or pulled in order to transfer it to a transport means 16, here in form of a rack 17. This transport means 16 is movable and guided on respective rails 18, so that it can e.g., automatically move along several molds 1, which are arranged side by side, one of which is only shown in FIG. 3. The transport means 16 is adapted to receive several of the mold elements 3 with the vacuum-fixed building material 7. As FIG. 3 shows, already one mold carrier 2 from a not-shown mold 1 is already received in the rack 17. The rack 17 comprises respective receiving means 19, here in form of longitudinal bars or carriers, which are e.g., provided with rollers or the like in order to easily move the mold element on them. The receiving means 19 are, as shown by the arrow P1, vertically movable, so that respective receiving means may be moved in place to receive a new mold element 3, whereafter the receiving means 19 with the mold element 3 is vertically moved and another receiving means 19 is moved in place in order to receive another mold element 3. The mold elements 3 are, as shown by the arrow P2, simply pushed into the rack 17 by respective pushing means, which may be arranged at the carrier 2, while these pushing action may also be performed manually, as the mold element 3 rolls on the roller elements 15. It may also be pulled into the rack 17 by using respective pulling means arranged at the rack 17. These pushing or pulling means may for example be pushing or pulling rods or the like.

[0075] The vertical movement of the receiving means 19 may be performed by respective electric motors or for example driving circulating chains or belts, to which the receiving means 19 are coupled, or respective spindle drives or the like. Also, the respective pushing or pulling means may be motor driven.

[0076] FIG. 3 shows a first embodiment of an inventive manufacturing arrangement 20 for producing preforms for turbine blades. It shows in this example three molds 1, which are arranged side by side. The mold 1a is equipped with a new mold element 3a, which is, see the arrow P3, pushed or anyhow else placed on the mold carrier 2a. The second mold 1b is equipped with the mold element 3b arranged on the mold carrier 2b. The building material 7b is already arranged on the mold element 3b, but for example not yet vacuum-fixed.

[0077] Finally, the mold element 3c of the third mold Ic is ready for the further processing and is therefore, as shown by the arrow P4, moved into the transport means 16 respectively the rack 17. The mold element 3c comprises the building material 7 covered by the vacuum cover 8c, it is therefore vacuum-fixed. As shown, it is already partially moved into the rack 17, in which already two other mold elements 3d, 3e are arranged.

[0078] The rack 17 moves on the respective rails 18 in the direction of the arrow P5 and therefore along the respective molds 1. At each mold 1 the respective mold element 3 comprising the fixed building material is received on respective receiving means 19 of the rack 17, until the rack 17 is fully loaded.

[0079] The rack 17 then moves to a heating means 21, i.e., a heating oven, which can be pre-heated respectively remains always at a certain temperature level necessary for melting the usually only locally applied binding agent in order to embed all the fiber material and core material etc. in a respective fluid binding matrix. Several mold elements are moved into the heating means 21, as shown by the arrow P6. In this illustration already several mold elements 3f, 3g are already in this heating means 21, which is shown partially opened just for illustration purpose. They are heated for a certain time necessary to build the preform. Regarding the way the mold elements are inserted in the heating means several possibilities are feasible, which are explained later.

[0080] Further shown is a cooling means 22, like a housing or unit comprising a cooling fan or the like, which is adapted to actively cool the heated preforms, which are, as shown by the arrow P7, transferred from the heating means 21 to the cooling means 22. This transfer will also be described later. The mold element capacity of the cooling means 22 corresponds to the mold element capacity of the heating means 21, so that all heated mold elements 3 can be transferred to the cooling means 22 and be cooled simultaneously.

[0081] In this cooling means 22 the hot preforms are cooled down to an ambient temperature, whereafter they are removed from the cooling means 22, as shown by the arrow P8 to be further processed.

[0082] As this principle layout clearly shows, the molds 1 are only used for preparing the building material 7 and for shaping the form of the building material 7 according to the requested preform shape and for fixing the building material 7 to the respective mold element 3. Right after the respective mold element 3 is removed from the mold carrier, a new mold element 3 may be put in place on the mold carrier, which new mold element 3 is completely surface cleaned to ensure that the building material 7 may be properly arranged.

[0083] The heating process is completely separated from the mold area. As only the heating is performed in the heating means, this heating means can be held on a constant temperature, which allows a very short heating operation.

[0084] The same holds for the cooling means 22, which allows for a separated cooling step, and which cooling means 22 can also be maintained on a certain cooling temperature or allows to actively run a certain cooling ramp in order to enhance the cooling.

[0085] Thus, an almost constant manufacturing may be realised, as it is constantly possible to provide respective loaded mold elements 3 ready for the heating and cooling processing. The time, for which a mold 1 is occupied, is very short and corresponds almost only to the time needed for arranging a new mold element 3 in place, loading the building material 7 and fixing it, and for removing the loaded mold element 3. As both the heating means 21 and the cooling means 22 are adapted to receive several mold elements, also the heating and cooling process is significantly faster, as a certain number of mold elements may simultaneously be processed.

[0086] FIG. 4 shows a first alternative regarding the transfer of the mold elements 3 into the heating means 21 and the cooling means 22. In this embodiment the mold elements 3 are arranged in the transport means 16, i.e., the rack 17, and are received on respective receiving means 19, which are, as shown by the double arrow P9, vertically movable, as previously mentioned.

[0087] In this embodiment, the complete transport means 16 with all the mold elements 3 moves into the heating means 21 and stay's there during the heating process. When the heating process is finished, the transport means 16 moves out of the heating means 21 and directly into the cooling means 22 to be finally cooled. After the cooling step is finished, the whole transport means 16 with the cool mold elements 3 comprising the cooled preforms is moved out of the cooling means 22, whereafter the mold elements 3 may be removed from the transport means 16 and the finished preforms may be removed from the mold elements 3 for further processing. In an alternative the transport means 16 may be moved to a storage area for storing the finished preforms.

[0088] The mold elements 3 will be, after the preforms are removed, automatically surface cleaned and will be automatically recirculated again for being arranged on an unloaded mold carrier 2 again.

[0089] In the embodiment of FIG. 5, again a transport means 16 respectively a rack 17 is shown, which comprises several mold elements 3 arranged on a respective vertically movable receiving means 19, as shown again by the arrow P9.

[0090] The heating means 21 is equipped with separate receiving means 23 which are vertically movable, as shown by the double arrow P10. The separate mold elements 3 of the transport means 16 are, as shown by the arrow P11, horizontally moved from the transport means 16 to the heating means 21 respectively from a receiving means 19 to a receiving means 23. For example, only the lowest mold element 3 is moved to the lowest position in the heating means 21. In the next step, the next mold element 3 of the transport means 16 is lowered, while the previous mold element received in the heating means 21 is raised, so that a new transfer may start until all mold elements are unloaded. As soon as the transport means 16 is unloaded, it returns to again receive new mold elements 3.

[0091] After the heating process is finished, the separate mold elements 3 are transferred to the cooling means 22. The set-up of the cooling means 22 is comparable to the set-up of the heating means 21. Also, the cooling means 22 comprises receiving means 24, which are, see the double arrow P12, vertically movable. Again, by using respective transfer means, as shown by the arrow P13, separate and single mold elements 3 are moved from the heating means 11 respectively a receiving means 23 to the cooling means 22 respectively a receiving means 24. Also, here the respective vertical movement is performed.

[0092] After the cooling is finished, the mold elements 3 with the cooled preforms are transferred to another transport means 25, again a rack, with a respective receiving means 26 for receiving the respective mold elements 3, as shown by the arrow P14. The receiving means 26 are, as shown by the arrow P15, also vertically movable. With this transport means 25 the mold elements 3 with the finished preforms may be transported to a storage area or to a further processing device etc.

[0093] It is to be noted that the transport means 25 is only optional. It is certainly possible to transfer the separate cooled mold elements 3 for example to a respective conveyor belt or the like and to transport them into a storage area or to a lifting device for vacuum-lifting the finished preforms from the mold element for further processing the preforms. The emptied mold element 3 will then be surface cleaned if so needed and recirculated.

[0094] FIG. 6 shows an embodiment with a first transport means 16, which set-up is identically to the transport means 16 of FIG. 5. Also, the heating means 21 and the cooling means 22 correspond in their set-up and function to the heating and cooling means 21, 22 of FIG. 6. In this embodiment, the heating means 21 and the cooling means 22 are distanced, thus a direct transfer of the mold elements is not possible. For the transfer a further transport means 27 is provided, comprising respective receiving means 28, e.g., beams or rails, on which the separate mold elements 3 are received from the heating unit 21, as shown by the arrow P16. Again, the receiving means 28 can be vertically moved, as shown by the arrow P17.

[0095] After the transport means 27, again a rack, is completely loaded, it moves to the cooling means 22, where the separate mold elements 3 are unloaded as shown by the double arrow P18 onto respective receiving means 24 of the cooling unit 22. After the cooling step is finished, the mold elements 3 may again be transferred to the transport means 25 or may be directly transferred to a conveyor belt etc.

[0096] In both embodiments according to FIGS. 5 and 6 the mold elements 3 are transferred separately into and out of the heating unit. The order, in which they are transferred into and out of the heating unit 21 may be the same. This means that each mold element 3 receives the same temperature treatment respectively remains for the same process time in the heating means 21. In case a mold element 3 respectively the building elements needs a shorter or longer heat treatment, the respective mold element may remain shorter or longer in the heating unit 21 than other mold elements 3, so that the transfer order may vary depending on the needed treatment time. This is possible due to the separate mold element transfer.

[0097] Finally, FIG. 7 shows another layout of a manufacturing arrangement 20. It again comprises in this example four molds 1, with each mold having a removable mold element 3. For arranging the building material 7 on the respective mold element 3, the building material 7 is arranged close to the respective mold 1 and is for example unwound from respective fiber mat rolls etc., while the binding agent is applied from respective hoppers or the like.

[0098] In this embodiment, a transport means 18 in form of a forklift is provided between the two rows of molds 1. This transport means 16 respectively forklift is adapted to take a loaded mold element 3 and to transport it to the heating means 21, as shown by the arrow P19. From the heating means 21 the mold element 3 is then transferred to the cooling means 22, from where it is then further processed as described.

[0099] The empty mold element 3 is then returned by another transport means 25 like a forklift after cleaning the surface of the mold element 3 for replacing it on a mold carrier 2.

[0100] This figure also shows the various rails 18, on which the transport means 25 moves, wherein this rails 18 may also be used by respective transport cars 29 used for distributing the building material.

[0101] Although the present invention has been disclosed in the form of embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

[0102] For the sake of clarity, it is to be understood that the use of a or an throughout this application does not exclude a plurality, and comprising does not exclude other steps or elements.