BINDER ACTIVATION BY MEANS OF LIGHT-EMITTING DIODES IN THE PRODUCTION OF FIBRE-REINFORCED PLASTIC LAMINATE

Abstract

An activation device used for binder activation during the production of a fiber-reinforced plastic laminate. The activation device has at least one light-emitting diode for heating a portion of at least one semi-finished fiber ribbon. A method is used for producing a fiber-reinforced plastic laminate. It comprises automatically laying at least one semi-finished fiber ribbon on a laying support, heating at least one portion of the semi-finished fiber ribbon by means of one or more light-emitting diode(s) of an activation device, and pressing the heated portion of the semi-finished fiber ribbon on the laying support.

Claims

1. An activation device for binder activation during the production of a fiber-reinforced plastic laminate, wherein the activation device has at least one light-emitting diode for heating a portion of at least one semi-finished fiber ribbon.

2. The activation device according to claim 1, which comprises a temperature measuring device for detecting a temperature of at least one of the heated portion, the activation device, or a heated laying support.

3. The activation device according to claim 2, wherein the at least one light-emitting diode is configured to heat a plurality of semi-finished fiber ribbons, which have been laid simultaneously next to one another, in one portion, and wherein the temperature measuring device is configured to separately detect the temperature of the heated portion individually or in groups for the plurality of semi-finished fiber ribbons.

4. The activation device according to claim 1, which comprises a control unit for the light-emitting diodes.

5. The activation device according to claim 4, which has a plurality of light-emitting diodes, and wherein the control unit is configured to control at least one of the light-emitting diodes individually and the light-emitting diodes in groups.

6. The activation device according to claim 1, which comprises a light guide which is configured to transmit radiation from the at least one light-emitting diode to the portion to be heated.

7. The activation device according to claim 1, which comprises at least one optical component, which is configured to influence radiation emitted from the at least one light-emitting diode between at least one of the at least one light-emitting diode and the portion, or the at least one light-emitting diode and a laying support, radiated thereby, for the at least one semi-finished fiber ribbon.

8. The activation device according to claim 1, which is configured to be integrated into a laying head, which can move relative to a laying support, of a device for producing a fiber-reinforced plastic laminate.

9. A device for producing a fiber-reinforced plastic laminate comprising: a feed means for feeding at least one semi-finished fiber ribbon onto a laying support, an activation device for binder activation during the production of the fiber-reinforced plastic laminate, wherein the activation device has at least one light-emitting diode for heating a portion of at least one semi-finished fiber ribbon, and a compacting element for pressing the heated portion of the semi-finished fiber ribbon on the laying support.

10. A method for producing a fiber-reinforced plastic laminate comprises automatically laying at least one semi-finished fiber ribbon on a laying support, heating at least one portion of the semi-finished fiber ribbon, and pressing the heated portion of the semi-finished fiber ribbon on the laying support, wherein the portion is heated by means of one or more light-emitting diode(s) of an activation device.

11. The method according to claim 10, further comprising detecting a temperature of at least one of the heated portion, the laying support, or the activation device, of the at least one light-emitting diode.

12. The method according to claim 10, wherein two or more semi-finished fiber ribbons are simultaneously laid substantially parallel on the laying support and wherein the temperature of the heated portion is detected separately for each semi-finished fiber ribbon.

13. The method according to claim 10, which comprises at least one of controlling the light-emitting diodes individually and controlling the light-emitting diodes in groups.

14. The method according to claim 10, wherein the heating procedure comprises feeding radiation from the at least one light-emitting diode into a light guide and supplying the radiant energy through the light guide to the portion of the semi-finished fiber ribbon.

15. The method according to claim 10, wherein the heating procedure comprises passing radiation through at least one optical component between at least one of the activation device and the portion and the at least one light-emitting diode and a laying support, irradiated thereby, for the at least one semi-finished fiber ribbon.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In the following, the present invention will be described in more detail with reference to the embodiments represented in the schematic figures, in which:

[0047] FIG. 1 shows an exemplary device according to the invention for producing a fiber-reinforced plastic laminate.

[0048] FIG. 2 shows an activation device, in use, according to an exemplary embodiment of the present invention.

[0049] FIG. 3a, 3b are views of a possible irradiation of semi-finished fiber ribbons by means of an exemplary activation device according to the invention.

[0050] FIG. 4 shows an activation device, in use, according to a further exemplary embodiment of the present invention.

[0051] The accompanying figures are to provide a further understanding of the embodiments of the invention. They illustrate embodiments and, together with the description, serve to explain the principles and concepts of the invention. Other embodiments and many of the mentioned advantages are revealed in view of the drawings. The elements of the drawings have not necessarily been drawn true-to-scale relative to one another.

[0052] In the figures of the drawings, identical, functionally identical and identically acting elements, features and components have been respectively provided with the same reference numerals, unless indicated otherwise.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0053] FIG. 1 shows a first exemplary device 10 according to the invention for producing a fiber-reinforced plastic laminate. The device comprises a feed means 11 for feeding at least one semi-finished fiber ribbon 20 onto a laying support 30. Due to the schematic side view of the device, only a single semi-finished fiber ribbon can be seen in FIG. 1; according to an advantageous embodiment, the feed means 11 delivers to the laying support 30 a plurality of semi-finished fiber ribbons, which extend in parallel, next to one another. In the situation shown, the laying support of the currently laid semi-finished fiber ribbon(s) 20 is a previously laid layer of semi-finished fiber ribbons; in another situation, the support could be a forming tool 40 and/or a substrate (not shown).

[0054] The feed means 11 is preferably configured to move relative to the laying support 30 in the direction of the arrow to deliver the semi-finished fiber ribbon successively to the laying support 30, in particular to deposit said ribbon thereon. In the figure, the feed means 11 is shown schematically as an unwinding roller, from which the at least one semi-finished fiber ribbon is unwound during the mentioned movement.

[0055] The device 10 also has a compacting element 12 for pressing portions of the at least one semi-finished fiber ribbon onto the laying support. The compacting element 12 is also preferably configured to move relative to the laying support 30 in the direction of the arrow. The at least one delivered and deposited semi-finished fiber ribbon can thereby be pressed in portions, i.e., gradually, onto the laying support.

[0056] Before a portion A of the semi-finished fiber ribbon is pressed on the laying support by the compacting element 12, it is heated by an activation device 100; in this way, a binder material in the semi-finished fiber ribbon is activated and thereby produces a tackiness of the semi-finished fiber ribbon, due to which the semi-finished fiber ribbon adheres to the laying support and in particular, does not slip.

[0057] In the example shown, the activation device 100 comprises a plate 120 on which light-emitting diodes 110a, 110b, 110c are mounted. In the example shown, the light-emitting diodes 110a, 110b, 110c are directed in particular or substantially onto the contact point P (or onto a straight line, running through said contact point, perpendicularly to the plane of the drawing), at which the delivered at least one semi-finished fiber ribbon is just contacting the laying support. The activation device with the light-emitting diodes 110a, 110b, 110c irradiates the portion A of the at least one semi-finished fiber ribbon 20 and thus heats it directly before it is pressed by the compacting element 12 onto the laying support. Furthermore, the portion is heated indirectly in that the activation device 100 also irradiates a region of the laying support 30, the heat of which then radiates onto the portion of the semi-finished fiber ribbon, particularly after said portion has been deposited.

[0058] The activation device 100 shown in FIG. 1 also has a temperature measuring device 130 for detecting a temperature of the heated portion A. In the present example, the temperature measuring device 130 is, for example, a pyrometer, directed onto region A, for detecting the temperature without making contact. The activation device 100 preferably comprises a control unit (not shown) which can control the light-emitting diodes on the basis of one or more temperatures detected thus; a control of this type preferably comprises a comparison of at least one detected value with one or more set value(s).

[0059] One embodiment is particularly preferred in which the light-emitting diodes 110a, 110b, 110c can be controlled individually and/or in groups. Thus, for example, subject to a detected temperature, the radiant power of the light-emitting diodes 110a, 110b and 110c could be adjusted independently of one another. If the activation device 100 has further light-emitting diodes in analogous positions (for example perpendicularly to the plane of the drawing), light-emitting diodes, for example, which are arranged along a straight line perpendicularly to the direction of the ribbons could be respectively combined into a common controllable group. In particular, for example light-emitting diodes which (like light-emitting diode 110c in the drawing) only irradiate the laying support, could thereby be adjusted in a different manner compared to light-emitting diodes which only irradiate the at least one semi-finished fiber ribbon to be laid (like light-emitting diode 110a in the drawing) and/or compared to light-emitting diodes which irradiate the semi-finished fiber ribbon to be laid as well as the laying support (like light-emitting diode 110b in the drawing). It is understood that, alternatively, other segmentations are possible.

[0060] FIG. 2 shows an activation device 200 in use, according to an alternative embodiment; the activation device 200 is heating a portion of a semi-finished fiber ribbon 20 which is laid on a laying support 30 and is pressed thereon by a compacting element 12, as in the procedure shown in FIG. 1.

[0061] The activation unit 200 comprises plates 220a, 220b which are respectively arranged on a surface of a basic body 240 of the activation unit 200 and on which a plurality of light-emitting diodes 210, 210b are respectively arranged. Some of the light-emitting diodes (namely those identified by 210a) are directed at a delivered portion of the semi-finished fiber ribbon 20 which is to be laid, in order to heat said portion. On the other hand, other light-emitting diodes (namely those identified by 210b) are directed at the laying support and thus indirectly heat the portion of the semi-finished fiber ribbon, in that the heat introduced into the laying support radiates into the portion of the semi-finished fiber ribbon after it has been applied. The light-emitting diodes can preferably be controlled individually or in groups (as described above).

[0062] Arranged inside the activation unit 200 is a cooling system 260, through which a cooling medium flows. In this way, heat loss from the light-emitting diode(s) can be dissipated.

[0063] The activation unit 200 further comprises two optical components 250a, 250b which are respectively lenses in the case shown. In this case, the optical component 250a is arranged between the activation device and the portion of semi-finished fiber ribbon to be heated or irradiated and the optical component 250b is arranged between the at least one light-emitting diode and the laying support 30, irradiated thereby, for the at least one semi-finished fiber ribbon. In both cases, the optical component is configured to influence, for example to refract and/or to focus radiation which is emitted by the at least one light-emitting diode. Consequently, it is possible to achieve a particularly advantageous irradiation and thus heating, which causes a corresponding binder activation and thereby adhesion of the semi-finished fiber ribbon to the laying support.

[0064] FIGS. 3a and 3b are two different perspective sketches of possible radiation paths of radiation which is emitted by light-emitting diodes 310a, 310b, 310c onto respective portions of semi-finished fiber ribbons 20a, 20b, 20c which extend in parallel. The different perspectives are marked in the figures by respectively indicated (x, y, z) coordinate systems.

[0065] FIG. 3a is a cross-sectional view of the semi-finished fiber ribbons 20a, 20b, 20c. Each of the semi-finished fiber ribbons 20a, 20b, 20c is irradiated by a light-emitting diode 310a, 310b, 310c associated therewith and is thus heated. The radiation is respectively passed through an optical component 350 (for example through a Fresnel lens) which, in the present case, refracts the radiation in a parallel manner and thereby orients it so that overlaps of the radiation from the different light-emitting diodes are prevented.

[0066] As can be seen in FIG. 3a, a spread of the radiation is refracted, which radiation spread extends in a plane orthogonal to a longitudinal direction of the semi-finished fiber ribbons (in the drawing, a spread of this type lies in the (x, y) plane which is the plane of the drawing in FIG. 3a). In contrast thereto, FIG. 3b shows that the optical component 350 does not refract a spread which extends in a plane parallel to the longitudinal direction of the semi-finished fiber ribbons, so that the radiation spreads out along the semi-finished fiber ribbons (of which only semi-finished fiber ribbon 20a can be seen in FIG. 3b due to the perspective); in this case, the mentioned plane is denoted as the (x, z) plane in the drawing of FIG. 3b.

[0067] Thus, the optical component 350 with its refraction according to FIG. 3a, 3b allows an irradiation and thus a heating of the semi-finished fiber ribbons 20a, 20b, 20c which is substantially free of overlaps (and can thereby be monitored, in particular controlled particularly effectively via the respective light-emitting diodes 310a, 310b, 310c) and which nevertheless advantageously reaches a greater portion of the semi-finished fiber ribbons 20a, 20b, 20c in each case.

[0068] FIG. 4 shows an activation device 400 in use, according to a further exemplary embodiment of the present invention. Analogously to the procedure shown in FIGS. 1 and 2, the activation device 400 heats a portion of a semi-finished fiber ribbon 20 which is laid on a laying support 30 and is there pressed thereon by a compacting element 12.

[0069] The activation unit 400 comprises a light guide 470, a discharge body 480 and a plurality of light-emitting diodes 410. In the embodiment shown, the light-emitting diodes 410 are arranged such that they are spatially separated from the location to which the at least one semi-finished fiber ribbon 20 is fed on the laying support 30 (for example, the light-emitting diodes 410 can be positioned outside a forming tool in which the at least one semi-finished fiber ribbon is laid on the laying support). The radiation emitted by the light-emitting diodes 410 is fed into the light guide 470 and delivered therefrom to the discharge body 480 which, during the use shown, is arranged at least partly between the semi-finished fiber ribbon to be laid and the laying support 30. Radiation which is emitted from the light-emitting diodes 410 and is guided through the light guide 470 can issue from the discharge body 480 and, in the example shown, is projected onto a portion of the semi-finished fiber ribbon 20 to be heated and also onto a region of the laying support.

[0070] In its interior, the discharge body can comprise micro lenses which can precisely control the issue of the radiation. In particular, the discharge body can be segmented so that radiation can be directed specifically onto a portion of one (individual) or more semi-finished fiber ribbons and/or onto the laying support 30, depending on a region in which it is fed into the discharge body.

[0071] The light guide 470 preferably comprises a plurality of bundles which are respectively associated with a semi-finished fiber ribbon 20 and/or with a surface of the discharge body so that radiation which is guided through a corresponding bundle impacts on an associated semi-finished fiber ribbon 20 or passes into an associated surface of the discharge body (in order to then pass out of a further associated surface of the discharge body).

[0072] While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms comprise or comprising do not exclude other elements or steps, the terms a or one do not exclude a plural number, and the term or means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.