Method to manufacture at least a component of a blade of a wind-turbine

1. A method to manufacture at least a component of a blade of a wind-turbine, comprising:

providing at least one layer of a composite structure; and

building up the at least one layer by automatically laying down a plurality of dry and unconnected single roving-bundles,

wherein the plurality of roving-bundles are laid down onto a carrier, which is positioned inside a forming tool or part of the forming tool, such that the plurality of roving-bundles are aligned unidirectionally inside the forming tool, the forming tool is arranged and shaped for building up a part of the blade, and

wherein the plurality of roving-bundles which are laid onto carrier are cut individually in a randomized manner to form an irregular intersection for a joining of a further blade component.

2. The method according to claim 1 , wherein the forming tool is a mould used for a vacuum assisted resin transfer-method.

3. The method according to claim 1 , wherein the forming tool is pre-impregnated or partially impregnated.

4. The method according to claim 1 , wherein at least one roving-bundle is laid down in a longitudinal direction of the forming tool.

5. The method according to claim 1 , wherein the carrier is used to transport the plurality of roving-bundles into a mould.

6. The method according to claim 5 , wherein paper or a membrane is used as carrier, wherein the paper or membrane allows an infusion of resin.

7. The method according to claim 5 , wherein the forming tool is positioned nearby the mould, and the carrier and the plurality of roving-bundles are lifted and positioned into the mould by help of a vacuum.

8. The method according to claim 7 , wherein the vacuum is applied by a machine through stacked layers of the plurality of roving bundles and onto the carrier, so the carrier is sucked towards the machine together with the roving-bundles.

9. The method according to claim 1 , further comprising individually cutting each of the plurality of roving-bundles to a predetermined length, when the respective roving-bundle is laid into the forming tool.

10. The method according to claim 1 , wherein a layup machine is used to lay-up and cut the roving-bundles on the forming tool, and the layup machine is moved forward and backward along a longitudinal axis of the forming-tool to build up the at least one layer by stacking a at least a portion of the plurality of roving-bundles.

11. The method according to claim 10 , wherein the plurality of roving-bundles is supplied by bobbins, which are located in a stationary fixture or which are attached to the machine.

12. The method according to claim 10 , wherein the machine uses cutting devices to individually cut each of the plurality of roving-bundle in a predetermined manner to achieve a specific length of the respective roving-bundle.

13. The method according to claim 10 , wherein a cutting-device is allocated to each single roving-bundle.

14. The method according to claim 10 , wherein a cutting-device is allocated to a number of the plurality of roving-bundles.

15. A method according to claim 12 , wherein a cutting device is located movable within the machine to be used as single cutting device for different roving bundles.

16. The method according to claim 10 , wherein the layup machine is a multi-axis machine comprising a carriage being designed to shuttle back and forth across the forming tool, and at least one layer of the plurality of roving bundles is fed into the forming tool in a predetermined direction between 0 and 180 degree.

17. A method according to claim 1 , wherein the manufactured component is a blade of a wind turbine.