DK180294B1

DK180294B1 - Method and apparatus for treatment of a fibre mat

Info

Publication number: DK180294B1
Application number: DKPA201970107A
Authority: DK
Inventors: Skovgaard Henrik; Marxen Mogens
Original assignee: Mm Composite As
Priority date: 2019-02-19
Filing date: 2019-02-19
Publication date: 2020-10-13
Also published as: WO2020169160A1; DK201970107A1

Abstract

An apparatus for treatment of a fibre mat is described. The fibre mat has in a first lateral direction a greater stiffness than in a second lateral direction, being perpendicular to said first lateral direction and being parallel with side edges of the fibre mat. The apparatus comprises: - a fibre mat supply roller - guiding means, - a resin applicator with resin application nozzles, - a curing oven, and - a control unit. Said apparatus further comprises: - a product roller for rolling up said resin-treated fibre mat, which roller has an open core, - a curing oven into which the product roller may be transferred after having rolled up the resin-treated fibre mat and - transfer means. The resin applicator nozzles are arranged to form stripes while continuously advancing the fibre mat through said resin applicator in order to form parallel resin stripes extending in the first lateral direction.

Description

DK 180294 B1 1 Method and apparatus for treatment of a fibre mat Field of the Invention The present invention relates to a method for treatment of a fibre mat having laterally extending material between side edges of the fibre mat and which material has in a first lateral direction a greater stiffness than in a second lateral direction, said first lateral direction being parallel with said side edges of the fibre mat, which method comprises the steps of: - providing a fibre mat, - advancing the fibre mat through a resin applicator in a transport direction for apply- ing resin onto the fibre mat, - partly impregnating the fibre mat in a resin applicator with resin stripes being spaced in the second lateral direction of the fibre mat, - curing the resin to form spaced stripes of cured resin.

Further, the present invention relates to an apparatus for treatment of a fibre mat hav- ing laterally extending material extending between side edges of the fibre mat and which material has in a first lateral direction a greater stiffness than in a second lateral direction, said first lateral direction being parallel with said side edges of the fibre mat, which apparatus comprises: - a fibre mat supply roller being arranged on a supply roller support and which supply roller has the fibre matt rolled up, which roller has an axis of rotation being parallel with said second direction, - guiding means for advancing the fibre mat through said resin applicator in a transport direction, - a resin applicator with resin application nozzles for applying resin on a surface of the fibre mat and partly impregnating the fibre with resin stripes being spaced in the sec- ond lateral direction of the fibre - a curing oven for curing the resin to form spaced stripes of cured resin, and - a control unit for obtaining signal from sensors and/or a vision system for control- ling the position and function of elements of the apparatus and/or the fibre mat treated.

DK 180294 B1 2 Background of the Invention It is well known to use fibre mats comprising glass fibres, carbon fibres, aramid fibres, organic fibres and combinations thereof when moulding composite parts.

Such fibre mats are typically used for forming a laminate which is impregnated with a resin and cured into a hardened state, thus forming a composite article. Such article can be a blade for a wind turbine.

Composite laminates usually comprise several layers of fibre mats. Normally, it is troublesome to handle multiple layers in a mould, since wrinkles can have a detri- mental effect on the finished product. The structural characteristics of a fibre-reinforced laminate are usually governed by the amount, type and orientation of the reinforcement fibres. Typically, the stiffness and strength of fibres can only be taken into account to the extent that loading occurs in the longitudinal fibre direction. Therefore, a traditionally designed laminate as- sumes that the fibres of the finished laminate will be oriented in the same direction as the direction of the fibres when placed in the mould. However, in some cases wrinkles in the fibre layers may occur as a result of the treatment process. In such cases, the wrinkled fibres no longer have the desired orientation, and severe overload of the lam- inate may be the result. Wrinkles may occur for a number of reasons. Wrinkles in fibre-reinforced laminates are typically prevented by a combination of arrangements. A method for avoiding wrinkles in the fibre layers consists of including layers of wrinkle-preventing material between the fibre layers. Wrinkle-preventing material is treated in such a way that it is stiffer than normal fibre material. When po- sitioned between layers of, for example, fibreglass mats, the fibres in the mats are largely prevented from wrinkling, because the mats are kept flat by the wrinkle- preventing material.

Such wrinkle- preventing material is used in order to be able to lay up the fibre mats in a mould without the risk of one or more layers being wrinkled.

DK 180294 B1 3 It is common to apply a resin along some of the fibres, especially in mats with unidi- rectionally aligned fibres. Such mats are known under the term unidirectional mats or UD mats.

Currently, the overall procedure comprises applying the resin to bundles of fibres spaced a few centimetres (e.g., 5 cm) apart from each other, then curing the resin in an industrial oven and finally rolling the resulting mat for storage until the resulting mat is to be used in a mould. The length of the fibre mats may be very long. It is common to provide the mats in rolls containing mats having a length of several hundreds of meters. In particular, the curing process has many disadvantages as the mat either needs to be fed in its entirety into a rather long oven or needs to be gradually fed into a shorter oven. While the first solution requires much space and implies a high deployment cost due to the required oven, the second solution leads to a very time consuming process. GB 2433466 A discloses a method of treating a fibre mat wherein a layer of a fibrous material is at least partly impregnated by a continuous layer of thermoset resin using a conventional laminating technique. The partly bonded layers are then placed on a moulding tool with the resinous layer facing the moulding surface, a vacuum bag is placed over the layers and vacuum tubes are positioned along the layers. Air is then evacuated from the layers and the resin is set to cure under a certain temperature and pressure, thereby forming a moulded element with a high quality surface finish. Hence, there is a need in the technical field of composite moulding of overcoming the aforementioned drawbacks of the prior art solutions. Object of the Invention The object of the invention is to overcome the drawbacks of the prior art solutions and to provide a method and an apparatus to speed up the treatment process for a fibre mat and to reduce the space required for the treatment and to provide a fibre mat which is suited for use in treatment a fibre reinforced laminate.

DK 180294 B1 4 Description of the Invention The aforementioned object of the invention is achieved by a method as described by way of introduction and in the preamble of claim 1; said method further comprises the steps of’

- applying the resin stripes on a surface of the fibre mat while continuously advancing the fibre mat through a resin applicator being provided with resin application nozzles in order to form parallel resin stripes extending in the first lateral direction being par- allel with the transport direction,

- rolling said fibre mat around a product roller having an open core allowing air to pass through the core and which product roller has an axis of rotation perpendicular to said first lateral direction to form a fibre mat roll before the curing step, and - curing the resin with the fibre mat in a rolled state.

The apparatus according to the invention will be as described by way of introduction and in the preamble of claim 8; said apparatus is further peculiar in that said apparatus further comprises: - a product roller for rolling up said resin-treated fibre mat, which roller has an open core allowing air to pass through the core and which roller has an axis of rotation per- pendicular to said first lateral direction to form a fibre mat roll, - a curing oven into which the product roller may be transferred after having rolled up the resin-treated fibre mat, - transfer means for transferring the product roller from the resin applicator to the cur- ing oven, that said resin applicator nozzles are arranged to form stripes while continuously ad- vancing the fibre mat through said resin applicator in order to form parallel resin stripes extending in the first lateral direction being parallel with the transport direc- tion.

This is a unique method and apparatus, as the prior art has not disclosed a method or an apparatus for applying resin stripes in the transport direction of a continuously ad- vancing fibre mat through a resin applicator.

In general, the fibre mat will be provided in the form of web-shaped material having a long length compared to the width of the web.

In this situation, the side edges of the

DK 180294 B1 fibre mat will be the side edges of the web.

Here, the first lateral direction will be par- allel to the longitudinal direction of the web, which will also be the transport direction of the fibre mat.

Said second lateral direction will typically be perpendicular to said first lateral direction or be arranged under an angle different from 90°. 5 The invention has the advantage that there is no need to employ a long oven into which the entire unrolled resin-treated fibre mat is feed or to gradually feed the un- rolled mat into a shorter oven.

In general, the rolled fibre mat will in the rolled state be transferred to a curing oven from the resin applicator.

However, the rolled resin-treated fibre mat may from the resin applicator be fed into a small oven only used for maintaining the temperature in the roll of the resin-treated fibre mat while being rolled up.

This obviously reduces the cost and the space required for the oven.

And the time needed to complete the curing process may be optimized as more curing ovens may be provided for one resin applicator.

The fibre mat roll is fed into the curing oven, which is separated from the resin applicator.

Also, such curing oven will be a small oven which only needs to accommodate the fibre mat roll.

In general, it is possible to have a batch of up to 10 or even more fibre mat rolls in the curing oven for a simultaneously curing of more fibre mat rolls treated in one resin applicator unit.

A sheet of foil prevents that the resin-treated fibres glue together when the mat is rolled before curing.

However, in case of applying resin stripes being orientated paral- lel to the transport direction, the production speed will be so high that there normally is no need to use such foil.

The foil does not stick to the resin-treated fibres, it does not melt in the oven and it can be easily removed before placing the mats in a mould for applying the final resin.

DK 180294 B1 6 Said fibres may comprise glass fibre mat or any other fabrics. Said resin may be polyester, vinyl ester, epoxy, phenol, polyurethane or other suitable types of resin, and may be applied to spaced-apart bundles of fibres (e.g., in case of unidirectionally aligned fibres). Resin may be a form of glue, which is fixed to, and thereby provides rigidity to, the respective fibres. According to the invention, said resin applicator comprises more movable nozzles for dispensing said resin. For example, in case of a unidirectional fibre mat, the nozzles may be aligned in a direction substantially perpendicular to the direction of the unidi- rectionally aligned fibres. Moreover, the nozzles may be movable in a direction sub- stantially parallel to the direction of the unidirectionally aligned fibres. An advantage herewith is that a plurality of nozzles simultaneously dispenses resin on a plurality of fibres, which makes the step of applying the resin fast.

According to the present invention, the unidirectionally aligned fibres will be orientat- ed in the first lateral direction being parallel with the transport direction. Nevertheless, embodiments where the nozzles are aligned in a direction substantially parallel to the direction of the unidirectionally aligned fibres are also encompassed by the invention. Herein, “substantially parallel” and “substantially perpendicular” are defined by an- gles in the range + 5° relative to a true “parallel and a true “perpendicular” orienta- tion. In context of the present invention, a laterally extending material is a material with a lateral dimension which is considerably larger than the thickness of the material. Moreover, the laterally extended layer and/or the laterally extended material may comprise different portions with a greater stiffness in a first lateral direction than in a second lateral direction, wherein the first lateral directions of the different portions may be orientated differently relative to each other.

DK 180294 B1 7 In general, the supply of fibre mat is provided in a rolled or folded configuration. In such case, said method further comprises rolling out or unfolding said fibre mat before applying said resin and/or said sheet of foil. Preferably, this method step comprises progressively rolling out or unfolding said fibre mat and applying said resin and/or said sheet of foil to an unrolled or unfolded portion of said fibre mat. An advantage connected herewith is that there is no need to wait until the whole mat is rolled out or unfolded before performing the next steps, thus speeding up the overall process. The product roller will be made from a heat-conducting material, preferably steel. Hereby heated air, which in the curing oven circulates within the open core, can heat the fibre mat roll from the inner side being in contact with the cylindrical surface of the product roller as well as from the outer side and the lateral sides of the fibre mat roll. A uniform heating and curing of the resin stripes is hereby possible in all layers of the fibre mat roll.

From the product roller, the fibre mat will after the curing of the resin be transferred to a delivery roller for transport to a costumer. When transferring the web to the delivery roll, the orientation of the windings on the roller may be reversed. Hereby it is possi- ble to deliver to the costumer a roll having the desired orientation of the fibre mat in the roll. During the curing of the resin, minor portions of the resin may stick to a near-lying layer in the roll. However, in general it is experienced that the sticking is negligible and there is no need to have a sheet of foil arranged on the fibre mat. However, in case of thin fibre mats and requirements for an amount of resin which soaks through the thickness of the fibre mat, a sheet of foil may be used to separate the near-lying layers in a roll. In an embodiment of the invention, said method is peculiar in that said fibre mat is a unidirectional fibre mat in which the unidirectionally-aligned fibres are parallel to said first direction, wherein said method further comprises the steps of: - applying said resin on a plurality of unidirectionally-aligned fibres on said unidirec- tional fibre mat for generating a resin-treated, unidirectional fibre mat, and

DK 180294 B1 8 - rolling said unidirectional fibre mat around an axis perpendicular to said unidirec- tionally aligned fibres. When applying the resin on unidirectionally-aligned fibres, the increased stiffness in the first lateral direction is obtained in the direction of the unidirectionally aligned fibres. When advancing a fibre mat having a long extension being a web-like fibre mat, the lengths would be many times longer than the width of the fibre mat. In this fibre mat, the unidirectionally aligned fibres could be in the longitudinal direction of the web, which corresponds to the transport direction of the web through the applying step in a resin applicator.

Hereby a web is obtained, in which it is possible to have an increased strength in the longitudinal direction of the web.

When rolling such fibre mat with unidirectionally aligned fibres on a roller in order to provide a roll of the resin-treated fibre mat, this would be effected around an axis which is perpendicular to the direction of the fibres.

When the resin stripes are applied in the longitudinal direction the rolling on a roller is easily effected seeing that the fibre mat will not have the increased stiffness until a curing has been effected.

However, it is necessary to have a roller with a relatively large diameter, as the curing of the resin is effected with the fibre mat in a rolled state.

In a further embodiment of the invention, said method is peculiar in that said method further comprises the step of: - choosing said open core of said product roller with a diameter between 800 mm and

2.000 mm, preferably between 1.200 mm and 1.400 mm and most preferably being

1.300 mm.

The width of such roll can be between 200 and 800 mm.

DK 180294 B1 9 With these dimensions and an open core of the roller, it is possible to cure the resin in a curing oven and having efficient temperature distribution which ensures a uniform temperature through the roll of the resin-treated fibre mat. Heating air in a curing oven will influence on the roll from all sides, including the inner side where air could enter into the open core of the product roller. It is important to have the open core in order to obtain sufficient space for air, and also to have a diameter which makes it possible to have the final fibre mat with resin cured in a roll having a sufficient large diameter, which ensures that the fibre mat can be laid out in a flat condition. Experiences have shown that the use of product rollers with diameters within the above-mentioned limits will make it possible that the final fibre mat with cured resin can be laid out in a flat condition. In order to obtain a better condition for laying in flat state the cured fibre mat after the curing procedure has ended, the fibre mat is transferred from a product roller to a de- livery roller where the orientation of the windings preferably is reversed. When transferring from the product roller to a delivery roller, it is also possible to deliver to a customer a roll of fibre mat having a correct orientation to be used in the equipment which is used for laying the fibre mat in a mould. In a further embodiment of the invention, said method is peculiar in that said method further comprises the step of: - controlling and adjusting the mutual position of said fibre mat and said resin applica- tion nozzles, when forwarding the fibre mat through the resin applicator. When receiving the untreated fibre mat in a roll from a manufacturer, this fibre mat may be supplied on a roller in a condition where the layers in the roll are not fully aligned.

Accordingly, it is beneficial that the method comprises the step of an adjustment of the mutual positions of the fibre mat and the resin applicator nozzles in order to ensure that the resin stripes are arranged correctly on the fibre mat when forwarding the fibre mat through the resin applicator.

DK 180294 B1 10 In a further embodiment of the invention, said method is peculiar in that said control- ling and adjusting step comprises: - sensoring the position of the resin stripes by means of a vision system, - generating a position signal to a control unit, in which the position signal is com- pared with a signal for the position of the resin application nozzles, - generating in said control unit an adjustment signal for movement means which ef- fects a mutual movement of the fibre mat and said resin application nozzles in said second direction, if necessary.

In order to control and adjust the mutual position, it is advantageous to have a vision system in order to obtain the position of the resin stripes on the fibre mat. Hereby the signals from the vision system can be forwarded to a control unit which adjusts the mutual lateral positions of the fibre mat on which the resin stripes has been applied and the resin application nozzles.

The apparatus may comprise a vision system. The vision system may be arranged for a movement in relation to a support table on which the fibre mat is advanced. When operating the apparatus according to the invention, the vision system will be in a fixed position.

The vision system is used to determine whether a correct application of resin stripes is established on the fibre mat.

The vision system will be connected with a control unit in which signals from the vi- sion system are handled, and which makes it possible to give alarm and/or to adjust the mutual positions of the resin application nozzles and the fibre mat.

The apparatus may also comprise sensor means which detect the positions of side edges of the fibre mat. These measurements are used for correct formation of the roll on the product roller.

In a further embodiment of the invention, said method is peculiar in that said method further comprises the step of: - detaching said fibre mat roll from the resin applicator,

DK 180294 B1 11 - transferring said fibre mat roll to a curing oven and - curing the resin in said curing oven having circulating air around the fibre mat roll and through the core of the roller on which the fibre mat roll is placed.

The fibre mat roll will preferably have an intermediate position after the resin applica- tor. Hereby it is possible to have the most efficient throughput in a plant. When the fibre mat roll is transferred from the intermediate position to a curing oven, it is also possible to increase the efficiency of the curing oven used for curing the resin.

Even though it might be possible to have the roller placed in a curing oven directly after the resin applicator, it is more beneficial to have an intermediate position and a transfer between the resin applicator and a curing oven. The time used for curing the resin may be up to 3-5 times longer than the time which is needed for applying the resin on the fibre mat and rolling up this fibre mat on the product roller.

The curing oven is provided with circulating air in order to ensure a uniform tempera- ture distribution and a uniform temperature throughout the fibre mat roll.

In a further embodiment of the invention, said method is peculiar in that said applying step comprises: - applying resin in an amount which only partly entering through the fibre mat thereby leaving a dry surface opposite to the surface of the fibre mat on which the resin stripes are applied.

When resin is applied in an amount not going through the fibre mat, there would be no risk for stitching between layers in the formed roll.

Therefore, the curing may be effected without the risk that the resin in different layers is cured in such a way that they would attach and be bound to each other.

Even if a minor amount of resin is going through the fibre mat, only a very limited stitching is established, which may easily be broken when unrolling a fibre mat from the product roller and transferring it to a delivery roller.

DK 180294 B1 12 Alternatively, it may also be possible that the fibre mat is placed on a foil and being resin-coated when being supported on the foil, which is also wound up on the product roller.

However, practise has shown that it is possible to control the amount of resin applied compared to the thickness of the fibre mat so precisely that a sheet of foil is not neces- sary to protect against a mutual bonding of layers to each other in the product roller during the curing step.

In a further embodiment of the invention, said apparatus is peculiar in that said resin application nozzles are arranged on a common support beam extending perpendicular to said transport direction, and that said support beam is arranged for movement of the resin application nozzles perpendicular to said transport direction.

An apparatus is most efficient with resin application nozzles arranged on a common support beam. Having this support beam extending perpendicular to the transport di- rection makes it possible to provide a number of parallel resin stripes on the fibre mat which is unrolled from the supply roller.

In a fibre mat, the distance between the resin stripes is between 40 and 100 mm, pref- erably about 50 mm, which will also be the distance between the resin application nozzles on the support beam.

In order to have a correct adjustment of the resin stripes on the fibre mat, the support beam is arranged for movement perpendicular to the transport direction. The transport direction will correspond to the first lateral direction in which the greater stiffness is obtained in the final fibre mat having resin in a cured state.

The nozzles may be arranged moveable on the support beam. Hereby they can be ar- ranged with different mutual distance between the nozzles arranged on one support beam. Therefore, the stripes may be provided, which does not need to have same mu- tual distance for all stripes.

DK 180294 B1 13 In a further embodiment of the invention, said apparatus is peculiar in that said appa- ratus is provided with: - a vision system for sensoring the position of the resin stripes on the fibre mat, which vision system is connected with the control unit, - movement means which are either connected with said resin application nozzles or connected with the supply roller support in order to effect a mutual movement of the fibre mat and said resin application nozzles in said second direction if necessary.

As already mentioned in connection with the method, it is advantageous to have a vision system for determining the position of the resin stripes on the fibre mat. The vision system may be considered to be a sensor means. The vision system will prefer- ably be arranged right after the position of the resin applicator as seen in the transport direction.

Furthermore, it is advantageous to have sensors for determining the position of the side edges of the fibre mat when the fibre mat is transferred through the resin applica- tor. Sensors determine the position of the side edges of the fibre mat when entering the resin applicator and make it possible to have an adjustment of the mutual position of the resin application nozzles and the fibre mat in order to have correct positioning of the resin stripes on the fibre mat.

The movement means may be arranged for a movement of the support beam or may be connected with movement means connected with the supply roller support in order to effect a lateral movement of the supply roller.

Alternatively, it is possible to have specific guide means for guiding the fibre mat by an engagement with the side edges of the fibre mat and thereby adjusting the position of the fibre mat, even if the supply roller support and the support beam are kept in fixed positions.

In a further embodiment of the invention, said apparatus is peculiar in that said open core of the product roller has a diameter between 800 mm and 2.000 mm, preferably between 1.200 mm and 1.400 mm and most preferably being 1.300 mm.

DK 180294 B1 14 As already mentioned, large diameter is necessary in order to have a final product which may be laid out in flat condition, and it is also necessary to have an open core in order to allow circulating air to enter the inner side of the product roll formed on the product roller. In order to have a heat transfer, the product roller will preferably be made of a metal and most preferably be made of steel. Hereafter, the invention will be described in connection with drawings illustrating non-limiting examples of a method and an apparatus for preparing a fibre mat for moulding. Description of the Drawing Fig. 1 illustrates a schematic view of an apparatus according to the invention for treatment of a fibre mat, and Fig. 2 illustrates a partial view of a fibre mat treatment according to a method and in an apparatus according to the present invention. Detailed Description of the Invention Fig. 1 illustrates an apparatus 1 for treating a fibre mat 2 with resin stripes.

The resin-treated fibre mat 2 is illustrated more clearly in Fig. 2. The fibre mat 2 is provided as a web having a lateral direction. The lateral direction is the plane of the web.

The fibre mat has side edges 3, 4 of the fibre mat. The fibre mat 2 has in a first lateral direction 5 a greater stiffness than in a second lateral direction 6. The second lateral direction 6 is perpendicular to the first lateral direction 5. The first lateral direction 5 is parallel with the side edges 3,4 of the fibre mat and also parallel with a transport direction 7 of the fibre mat. In Fig. 2, the fibre mat 2 is shown with six resin stripes 8 arranged in parallel form and parallelly with the transport direction 7. The resin stripes will in the final product be

DK 180294 B1 15 provided in cured state. The fibre mat will, after having passed through an applicator device, be provided in uncured state and therefore it can easily be rolled up. This will be explained further below with reference to Fig. 1 The apparatus illustrated in Fig. 1 comprises a roller 9 being provided with a roll 10 of untreated fibre mat material. The untreated fibre mat 11 in the roll 10 is preferably provided with unidirectionally aligned fibres in the longitudinal direction of the web forming the roll 10.

11 designate the fibre mat in form of an untreated web which is unrolled from the roll

10.

The untreated fibre mat/web 11 is advanced in accordance with the transport direction

7.

The roller 9 rotates the operational direction 12 and has an axis of rotation 13 being perpendicular to the transport direction 7 and accordingly being perpendicular to the first direction 5 of the fibre mat.

The apparatus comprises a lifting table 14 which includes a support bearing 15 for the roll 9. The support bearing 15 comprises a stop 16 ensuring that the roll is arranged in the bearing 15 and rotates in accordance with the operational direction 12 without leaving the bearing 15. There may be arranged a brake in connection with the bearing 15 in order to ensure correct tensioning in the fibre mat/web 11. The lifting table 14 is provided with scissor arms making it possible to adjust the height of the roll 10. Alter- natively, other lifting structures may be used.

The apparatus furthermore comprises a resin applicator 17. The resin applicator has a height 18, a width 19 and a length 20 in order to provide a support for the untreated fibre mat 11 and the resin stripes provided fibre mat 2 and also a support for further equipment to be explained below.

The resin applicator 17 comprises a support table 21 which at one end comprises a guide roller 22 being provided at entry end of a support plate 23. A corresponding

DK 180294 B1 16 guide roller is also arranged at the other end of the support plate (not visible in the Figure). The support plate 23 provides a support surface on which the fibre mat is guided through the resin applicator 17.

The guide roller 22 is associated with an encoder 24. The encoder has a housing 25 which through an arm 26 is connected with a metering bar 27 arranged over the guide roller 22, with the fibre mat 11 advanced there between.

Furthermore, the resin applicator 17 comprises a number of resin application nozzles 28 being provided on a common support beam 29. The support beam 29 is arranged with an extension perpendicular to the transport direction 7. Moreover, the support beam 29 is provided on a support 30 for a transversal movement 31 perpendicular to the transport direction 7. The resin application nozzles 28 are connected with a pump 32 through tubes (not shown). Beneath the resin application nozzles 28, a collector 33 is arranged for collecting sur- plus resin in a container 34. In the container 34, a cleaning of the resin may be effect- ed before the resin is transferred to the pump 32 and pumped forward to the resin ap- plication nozzles 28. The resin applicator 17 furthermore comprises a vision system 35. The vision system 35 1s arranged for a movement in vertical direction 36 and a horizontal direction 37 parallel to the transport direction 7. The vision system may possibly also be movable in a direction perpendicular to the transport direction 7. Hereby it is possible to adjust the position of the vision system 35 in relation to the support plate. When operating the apparatus according to the invention the vision sys- tem will be in a fixed position. The vision system 35 is used to determine whether a correct application of resin stripes 8 is established on the fibre mat 2.

DK 180294 B1 17 The vision system will be connected with a control unit (not illustrated) in which sig- nals from the vision system are handled, and which makes it possible to give alarm and/or to adjust the mutual positions of the resin application nozzles and the fibre mat. The fibre mat 2 leaves the support plate 23 in a condition where resin stripes 8 are provided in the longitudinal direction of the web forming the fibre mat. The apparatus furthermore comprises a product roller 38 on which a roll 39 of resin treated fibre mat 2 is provided.

The roller 38 has an operational direction 40. The roller 38 may be lowered or raised as indicated with arrow 41. A support structure 42 for the roller 38 is provided with a motor 43 which ensures the correct rotation of the roller 38. The roller 38 is arranged on a support 44. Furthermore, side guides 45 are arranged in order to ensure that a roll is placed correctly in the apparatus. The roller 38 has a shaft 46 which is arranged in bearings (not shown). The roller 38 is provided with a rim 47 encircling an open core 48. On the rim 47, the roll 39 is provided. The apparatus is connected to a control unit (not illustrated). The control unit may be arranged in association with the support table 21 or in a position separated from the resin applicator 17. The control unit is used for controlling the mutual positions of the untreated fibre mat 11, the resin-treated fibre mat 2 and the support beam 29 for resin application nozzles 28, in order to obtain a correct positioning of the resin stripes 8. The control unit is also connected with the vision system 35 in order to give feedback for the quality of the resin stripes provided on the fibre mat 2. The open core 48 of the product roller 38 will have a diameter between 1000 mm and 1600 mm. The width will be between 500 and 800 mm.

DK 180294 B1 18 When the product roller 38 is filled with the fibre mat forming the roll of resin provid- ed fibre mat 2, it will be removed from the apparatus and transferred to a curing oven. In the curing oven, curing is effected with circulating air circulating around the roll 39 and also inside the open core 48. Due to the metal in the rim 47, a good heat transfer will be obtained and an effective and uniform curing can be obtained. The curing oven is not illustrated, seeing that such curing oven with circulating air is well known.

Reference numbers:

1. apparatus

2. fibre mat

3. side edge

4. side edge

5. first lateral direction

6. second lateral direction

7. transport direction

8. resin stripes

9. supply roller

10. roll

11. untreated fibre mat

12. operational direction

13. axis of rotation

14. lifting table

15. support bearing

16. stop

17. resin applicator

18. height

19. width

20. length

21. support table

22. guide roller

23. support plate

DK 180294 B1 19

24. encoder

25. housing

26. arm

27. metering bar

28. resin application nozzles

29. support beam

30. support

31. transversal movement

32. pump

33. collector

34. container

35. vision system

36. vertical direction

37. horizontal direction

38. product roller

39. roll

40. operational direction

41. arrow

42. support structure

43. motor

44. support

45. side guides

46. shaft

47. rim

48. open core

Claims

DK 180294 B1 1 PATENTKRAV

A method of treating a fiber mat (2, 11) having laterally extending material between side edges (3, 4) of the fiber mat (2, 11) and which material in a first lateral direction (5) has greater stiffness than in a secondary lateral direction (6), said first lateral direction (5) is parallel to said side edges (3, 4) of the fiber mat (2, 11), which method comprises the steps of: - providing a fiber mat (11), - advancing the fiber mat (11 through a resin applicator (17) in a conveying direction (7) to apply resin to the fiber mat (11, - partially impregnating the fiber mat (11) in the resin applicator (17) with resin strips, - curing the resin, characterized by, said method further comprising the steps of: - applying the resin strips (8) to a surface of the fiber mat (11), while continuously advancing the fiber mat (11) through the resin applicator (17) provided with resin application nozzles (28) to form parallel resin streaks that run in a first lateral direction (5) parallel to the conveying direction (7), the resin strips (8) are separated in the secondary lateral direction (6) by the fiber mat (11), - providing said resin strips (21) with an extension which does not reach said side edges (3, 4), thereby leaving an edge area (30) along the side edges (3, 4) free of resin streaks (21), - rolling said fiber mat (2) around a product roll (38), having an open core (48) allowing air to pass through the core (48), and said product roll (38) having an axis of rotation perpendicular to said first lateral direction (5) to form a fiber mat roll (39) before the curing step, and - curing the resin together with the fiber mat (2) in the rolled-up state to form separate strips of cured resin.

The method according to claim 1, characterized in that said fiber mat (2, 11) is a unidirectional fiber mat, wherein the unidirectional in line fibers are parallel to said first lateral direction (5), said method further comprising the steps of: applying said resin to a plurality of unidirectional in-line fibers on said unidirectional fiber mat to generate a resin-treated, unidirectional fiber mat, and

DK 180294 B1 2 - rolling said unidirectional fiber mat around an axis perpendicular to said unidirectional on line fibers.

The method according to claim or 2, characterized in that said method further comprises the step of: - selecting said open core (48) of said product roll (38) with a diameter between 800 mm and 2,000 mm, preferably between 1,200 mm and 1,400 mm and most preferably 1,300 mm.

The method according to any one of the preceding claims, characterized in that said method further comprises the steps of: - controlling and adjusting the mutual placement of said fiber mat (2, 11) and said resin application nozzles (28) in advancing the fiber mat ( 2, 11) through the resin applicator (17).

The method according to claim 4, characterized in that said control and adjustment steps comprise: - sensing the position of the resin stripes (8) by means of a vision system (35), - generating a position signal for a control unit, wherein the position signal compares a signal for the position of resin application nozzles (28), - generation 1, said control unit an adjustment signal for movement means which, if necessary, effect mutual movement of the fiber mat (2, 11) and said resin application nozzles (28) in said secondary lateral direction ( 6).

The method according to any one of the preceding claims, characterized in that said method further comprises the steps of: - releasing said fiber mat roll (39) from the resin applicator (17). transferring said fiber mat roll (39) to a curing oven, and - curing the resin in said curing oven having circulating air around the fiber mat roll (39) and through the open core (48) of the product roll (38) on which the fiber mat roll (39) is located.

The method according to any one of the preceding claims, characterized in that said application step comprises:

DK 180294 B1 3 - application of resin in an amount which only partially penetrates the fiber mat (11), thereby leaving a dry surface opposite the surface of the fiber mat (11) on which the resin strips (8) are applied.

An apparatus for treating a fiber mat (2, 11) having laterally extending material between side edges (3, 4) of the fiber mat (2, 11) and which material in a first lateral direction (5) has greater stiffness than in a secondary lateral direction (6), said first lateral direction (5) is parallel to said side edges (3, 4) of the fiber mat (2, 11), which apparatus comprises: - a fiber mat supply roller (9), which is arranged on a supply roller support, and which supply roller (9) has a wound fiber mat, which supply roller (9) has an axis of rotation (13) parallel to said secondary lateral direction (6), - guide means for advancing the fiber mat ( 11) through a resin applicator (17) in a conveying direction (7), and - the resin applicator (17) has resin application nozzles (28) for applying resin to a surface of the fiber mat (11) and partially impregnating the fiber mat (11) with resin strips ( 8) separated in the secondary lateral direction (6) by fibers the mat (11), characterized in that said apparatus further comprises: - a product roll (38) for winding said resin-treated fiber mat (2), which product roll (38) has an open core (48) which allows air to pass through the core. (48) and which product roller (38) has an axis of rotation perpendicular to said first lateral direction (5) to form a fiber mat roller (39), a control unit for obtaining signals from sensors and / or a vision system (35) for controlling the position and function of elements of the apparatus and / or the treated fiber mat (2), - a curing oven to which the product roll (38) can be transferred after winding the resin-treated fiber mat (2) to cure the resin to form separate strips of cured resin, - transfer means for transferring the product roll (38) from the resin applicator to the curing oven, and said resin application nozzles (28) being arranged to form resin strips (8) during continuous feeding of the fiber mat (11) through said resin applicator (17) to form

DK 180294 B1 4 parallel resin strips (8) extending in the first lateral direction (5), which are parallel to the transport direction (7).

The apparatus according to claim 8, characterized in that said resin application nozzles (28) are arranged on a common support beam (29) extending perpendicular to said conveying direction (7), said support beam (29) being arranged for movement of resin application the nozzles (28) perpendicular to said conveying direction (7).

The apparatus according to claim 8 or 9, characterized in that said apparatus is provided with: - a vision system (35) for sensing the position of the resin stripes (8) on the filter mat (2), which vision system (35) is connected to the control unit, moving means either connected to said resin application nozzles (28) or connected to the supply roller support to effect, if necessary, a mutual movement of the fiber mat (2, 11) and said resin application nozzles (28) in said secondary lateral direction (6).

The apparatus according to any one of claims 8-10, characterized in that said open core (48) of the product roll (38) has a diameter between 800 mm and 2,000 mm, preferably between 1,200 mm and 1,400 mm and most preferably 1,300 mm.