Component made of fiber composite material

Abstract

Component with at least one fiber layer (12) between front and rear laminates (13, 14), with at least one recess (18) in the rear laminate (14) extending approximately to the plane of the fiber layer (12), with locally recessed opaque coating (15) on the rear laminate (14) behind axially associated emission areas (16) in front of the front laminate (13), and with a rough coating (23) on the front laminate (13) which is interrupted in the emission areas (16).

Description

[0001] A component described in more detail in DE 10 2009 019 495 A1 essentially consists of a fiber composite material, such as a so-called organic sheet, deformed under the influence of heat and pressure. This is a single- or multi-layer fiber structure that is enclosed, usually on both sides, in a matrix of thermoplastic laminate. The back of a fiber composite material, facing away from the view, is usually covered with a film or a coating of paint to provide an opaque coating. Fiber extensions, oriented primarily in the direction of the expected mechanical stress, give the component excellent strength properties despite its low wall thickness and low weight. Components made from this material are rigid and impact-resistant. Even flat to shallowly curved housing shells with bent edges are exceptionally rigid and torsion-resistant.Structures that shimmer or emboss through the lamination matrix, such as woven or knitted fiber patterns, impart a special feel and, especially when carbon-colored fibers are used, a sophisticated appearance to the component. By weaving in carbon or other electrically conductive fibers, targeted electrothermal or electromagnetic effects (such as antenna or shielding) can be achieved locally, or circuits can be wired.

[0002] US 4,053,340 A, WO 2005 / 095189 A1 and US 2010 / 0130081 A1 disclose various illuminable components which do not have a fiber layer.

[0003] The unpublished German patent application 10 2011 115 803.4 proposes providing a rear milled recess for local backlighting and, if necessary, filling it with light-conducting plastic. The present invention is based on the technical problem of further developing the application scenario of fiber-reinforced components, which are already versatile in use, without restrictions regarding thermoplastic or thermosetting material or fiber types, arrangements, or lengths.

[0004] This is not achieved by the fact that, according to DE 10 2010 039 270 A1, luminous foils and, if applicable, touch sensors are recessed into a solid foamed plastic layer on the visible and emission sides, and are overlapped at the edges by openings in a decorative layer, perhaps a metal one, located on top of the plastic layer, with structural stiffening provided by a thin functional layer made of semi-finished fiber composite material behind the plastic layer. Such a layer arrangement of injected and foamed plastic between the perforated decorative layer and the unperforated functional layer cannot be backlit by ambient light or light sources for geometrically defined, decorative, or informative radiation.

[0005] WO 02 / 32692 A1 discloses another fiber-reinforced component in which the fiber layer is irradiated from the back.

[0006] The problem is solved according to the invention by the essential features specified in the main claim. By locally removing the lacquer layer or similar opaque coating on the rear laminate of a fiber composite matrix and locally milling it into this rear laminate, ideally up to approximately the level of the fiber structures, the fiber composite component, which otherwise only translucently translucent, is locally given a decidedly decorative or informative effect. This can include, for example, a decorative pattern, a company logo, or operational information, and can also be further developed to trigger switching functions.

[0007] Side walls that are locally oriented, inclined or concave in cross-section instead of transverse to the fiber plane, lead to locally less contrast-limited radiation.

[0008] The effect is already apparent on the visible side due to the mere ambient brightness from behind. It becomes even more pronounced when the component is illuminated from behind, and more informative when different, mutually isolated areas of such rear material interventions are specifically controlled by switching their backlighting on and off or changing its color.

[0009] If such a translucent or even light-emitting area is backed by a translucent electrode, then this area can be specifically used for a switch function. When a fingertip is brought close to this area of ​​the front and visible side of the composite material, with its matrix acting as a dielectric, the effective capacitance changes, which can be interpreted by a resonance or other evaluation circuit as confirmation of or a request to actuate a switch to trigger circuit functions. Different symbols or other geometries of the transmissible areas allow such functions to be easily differentiated from one another. Such an electrode can be arranged behind the rear laminate in the area of ​​a lacquer recess.However, the reaction in the form of the change in capacitance is more sensitive if the electrode is embedded at the back into the bottom of a depression in the matrix in order to reduce the distance to the front radiation and action area.

[0010] In principle, milled recesses or similar depressions can also be made in the visible, front laminate of the fiber composite matrix. To prevent contamination, however, these recesses should then be filled or covered with a translucent, curing material; this could, however, impair the surface feel. If the component is covered with a rough, surface-roughened paint layer or film on the visible side, this is best removed locally to create a sharply defined emission zone. If the fiber structure in the matrix of an organic sheet or similar fiber composite material then shines through in this emission zone when backlit, this can be considered a special design feature.

[0011] Additional developments of the invention and modifications thereof emerge from the further claims and, also with regard to their advantages, from the following description of a preferred implementation of the invention, which is shown in the drawing, enlarged to scale and abstracted to show the essential functions.

[0012] The sole figure in the drawing shows a fragmentary sectional view of a component with a locally translucent fiber composite material 11, referred to as an organic sheet. This essentially consists of at least one, for example, woven, long- and / or short-filament fiber layer 12, which is plastic-impregnated by pressing it between, usually thermoplastic, laminates 13, 14 and embedded in this matrix. The fiber composite material 11 is usually coated on the back with an opaque lacquer or similar coating 15. Such a fiber composite material 11 is, if at all, only diffusely translucent and therefore cannot be used as a luminous information or decorative carrier, for example, in addition to its actual component function.

[0013] In order to nevertheless achieve geometrically defined local radiation areas 16 on the front laminate 13, correspondingly geometrically defined recesses 17 are introduced into the coating 15 at the rear, or milled recesses or similar depressions 18 are introduced into the rear laminate 14. If the fiber composite material 11 is coated with a scatter-reflecting rough coating 23 on the visible side, i.e. on the front laminate 13 of its matrix, this is expediently removed locally in the interest of a high-contrast border of the radiation area 16, which is coaxial with the recess 17 or milled recess 18 but not necessarily congruent.

[0014] The rear opaque coating 15 can be selectively removed using laser energy, for example, to create lettering or ornamentation. Depressions 18 can be of varying depths for areas 16 with different levels of brightness and can extend into the area of ​​the fiber layer 12. However, in the case of a single-layer fiber composite material 11 as outlined, the fiber layer 12 is not affected as much as possible in the interest of mechanical stability, thus limiting the depression 18 to a maximum of the material thickness of the rear laminate 14 of the fiber matrix.For example, created using a finger milling cutter, the rear depressions 18 can have not only circular geometries at certain points, but also decorative or informative channel-like shapes with side walls oriented transversely to the fiber plane. Instead, locally inclined or concavely curved side walls, which can be easily created using appropriate milling head geometries or by back-side impressions in the thermoplastic matrix, lead to locally targeted, less contrast-limited radiation. In individual cases, it may also be expedient to modify the radiation penetration of the fiber composite material by applying structures to the back during injection molding.

[0015] In a component prepared in this way and positioned, for example, as a panel, even the ambient brightness accessible from the rear is sufficient to allow the geometries of, for example, rear recesses 17 or depressions 18 to shine through on the visible side as emission areas 16. However, emission areas 16 are particularly prominent when illuminated from behind, particularly selectively, for example, with regard to color and intensity, by at least one light source 19, such as a light-emitting semiconductor diode (LED). For this purpose, light chambers 20 associated with the recesses 17 or depressions 18 are expediently sealed off from one another behind the fiber composite material 11 in order to be able to control the individual emission areas 16 independently of one another without mutual interference.

[0016] A fiber composite material 11 equipped in this way can be used as the housing wall of, for example, a battery-operated, portable electronic device, and thus, in what is essentially only a mechanically stabilizing and protective component, can also assume direct display functions. Instead or additionally, as already discussed above, it can also be designed for switch functions. For this purpose, in the exemplary embodiment sketched in the drawing, a translucent electrode 21 is inserted into a recess 18 and connected to an evaluation circuit 22, which responds and triggers another function, for example, when an operator sufficiently approaches the locally assigned radiation area 16 with a fingertip.Such actuation can be prompted by illuminating the emission area 16 as a result of controlling the associated light source 19, for example from the evaluation circuit 22; or to acknowledge the activation of the function, the light source 19 is redirected, for example, by modifying its intensity and / or color emission and / or emission period.

[0017] According to the invention, a component with fiber composite material 11 such as the so-called organic sheet has, in the case of visible-side radiation areas 16 axially assigned to these but not necessarily geometrically congruent therewith, at least one recess 17 in an opaque coating 15 and / or at least one depression 18 milled or formed into the laminate 13 or 14 of the matrix of the fiber composite material 11, which is backlit from a sealed light chamber 20 by at least one light source 19 which, if possible, can be controlled in terms of intensity, timing or color.The light sources 19 can be connected to the evaluation circuit 22 for at least one capacitance with a light-permeable electrode 21, which is arranged behind a radiation area 16 and preferably embedded in a recess 18 to trigger switching functions by approaching a fingertip to the associated radiation area 16. Thus, functional functions can now be integrated into housing parts made of fiber composite material 11 that actually only fulfill mechanical protective functions. These functional functions previously required the logistical and manufacturing effort for information and functional elements such as displays and switches to be individually mounted in housing shells. List of reference symbols 11 fiber composite material (with 12 in matrix of 13 / 14) 12 fiber layers (between 13 / 14) 13 front laminate (of the matrix of 11) 14 back laminate (of the matrix of 11) 15 opaque coating (behind 14) 16 Radiation area (out of 13) 17 recess (in 15) 18 depressions (in 14) 19 Light source (behind 17, 18 in 20) 20 light chambers (behind 17, 18) 21 Electrode (in 18, on 22) 22 evaluation circuit (for capacity with 21) 23 Rough coating

Claims

[1] Component with at least one fiber layer (12) between front and rear laminates (13, 14), with at least one depression (18) in the rear laminate (14) which extends approximately into the plane of the fiber layer (12), with a locally recessed opaque coating (15) on the rear laminate (14) behind axially assigned radiation areas (16) in front of the front laminate (13), and with a rough coating (23) on the front laminate (13) which is interrupted in the radiation areas (16). [2] Component according to the previous claim, characterized by that depressions (18) have inclined or concavely curved side walls in cross-section. [3] Component according to the preceding claim, characterized by that the fibre layer (12) is not attacked by the depression (18). [4] Component according to one of the preceding claims, characterized by that the depression (18) runs in a channel-like manner. [5] Component according to one of the preceding claims, characterized by that it is backlit by at least one light source (19). [6] Component according to the preceding claim, characterized by that the light source (19) is color, intensity and / or clock controllable.

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