Lining element, and process for manufacturing a lining element

Abstract

A lining element for use in a vehicle in order to cover an airbag includes a dimensionally stable backing layer with a first predetermined breaking region which is delimited from a surrounding region and/or from a second predetermined breaking region by at least one predetermined breaking line, where a plurality of regularly spaced predetermined breaking points are disposed along the predetermined breaking line.

Claims

1. A method for producing a lining element by an injection molding integral foam method, wherein the lining element comprises: a dimensionally stable backing layer with a first predetermined breaking region which is delimited from a surrounding region and/or from a second predetermined breaking region by at least one predetermined breaking line, wherein a plurality of regularly spaced predetermined breaking points are disposed along the predetermined breaking line, wherein the breaking points are recesses in the backing layer, wherein the backing layer has a visible side and a rear side facing away from the visible side, and wherein the recesses are disposed only on the visible side of the backing layer such that the recesses have a respective depth in the backing layer that reduces a thickness of the backing layer in regions of the recesses to a residual thickness; and a decorative layer disposed flat on the backing layer on the visible side of the backing layer, wherein a first surface of the decorative layer directly above one of the plurality of regularly spaced predetermined breaking points disposed on the visible side forms a plane together with a second surface of the decorative layer, wherein the second surface is directly adjacent to the first surface and completely surrounds the first surface such that the decorative layer on the visible side of the backing layer does not have any recesses in a region opposite the recesses of the backing layer; and the method comprising: injecting a fiber composite material into a cavity formed between a first die side and a second die side of a die to form the backing layer; compressing the backing layer by bringing the first die side and the second die side of the die toward each other before the cavity formed between the first die side and the second die side has been enlarged in the injection molding integral foam method in order to foam the injected fiber composite material and, via the compressing, forming the recesses in the backing layer by impressing a plurality of projections which are disposed or formed on the first die side into the backing layer; after the compressing, enlarging the cavity formed between the first die side and the second die side and foaming the injected fiber composite material of the backing layer such that the backing layer is expanded; and removing the backing layer from the die and disposing the decorative layer flat on the visible side of the backing layer such that the first surface of the decorative layer directly above one of the plurality of regularly spaced predetermined breaking points disposed on the visible side forms the plane together with the second surface of the decorative layer and such that the decorative layer on the visible side of the backing layer does not have any recesses in a region opposite the recesses of the backing layer.

2. The method according to claim 1, wherein the decorative layer is leather.

3. The method according to claim 1, wherein the backing layer forms a welding rib on the rear side and wherein at least some of the plurality of regularly spaced predetermined breaking points are disposed opposite the welding rib.

4. The method according to claim 1, wherein the rear side of the backing layer has a reinforcing network which is disposed on the backing layer or in the backing layer.

5. The method according to claim 4, wherein the reinforcing network includes aramid fibers.

6. The method according to claim 1, wherein the recesses have a shape that is cylindrical, cuboidal, conical, or pyramidal and/or wherein edges of the recesses are rounded.

7. The method according to claim 1, wherein the recesses have a depth of between 1 mm and 4 mm, a width of between 1 mm and 3 mm, a length of between 1 mm and 10 mm, and/or wherein a distance from one recess to a further recess is between 1 mm and 4 mm, and/or wherein the backing layer has a thickness of between 2 mm and 6 mm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a detail of a lining element with a predetermined breaking contour with two predetermined breaking regions from a horizontal projection;

(2) FIG. 2 shows a sectional view through a backing layer;

(3) FIGS. 3a-3d show various recess geometries from the top view; and

(4) FIGS. 4a-4c show various states of the backing layer during the method for producing the backing layer.

DETAILED DESCRIPTION OF THE DRAWINGS

(5) The figures are shown schematically by way of example. The same reference signs in the figures indicate identical functional and/or structural features.

(6) FIG. 1 shows a lining element 1 with two predetermined breaking regions 3. The predetermined breaking regions 3 are each delimited by four predetermined breaking lines 4, wherein one predetermined breaking line 4 lies between the predetermined breaking regions 3 and delimits the two predetermined breaking regions 3 from each other such that a total of seven predetermined breaking lines 4 run on the lining element 1. The predetermined breaking lines 4 of the predetermined breaking regions 3 that provide a delimitation with respect to the surrounding region 5 merge into one another such that the corners of the predetermined breaking regions 3 are rounded with respect to the surrounding region 5. The individual predetermined breaking points are arranged along the respective predetermined breaking lines, wherein the distances and dimensions of the predetermined breaking points of the predetermined breaking lines are coordinated with respect to one another between the predetermined breaking lines.

(7) FIG. 2 shows a sectional view through a lining element 1. A recess 7 is arranged on the visible side of a backing layer 2 and a decorative layer 6 composed of leather is arranged on the visible side of the backing layer 2 such that the recess 7 is covered. The backing layer 2 is composed of a fiber composite material foamed to form an integral foam, wherein the backing layer is produced in the injection molding integral foam method. The edge regions of the backing layer 2 essentially have no pores or very small pores in comparison to the inner regions of the backing layer, and therefore the backing layer 2 has a flat surface from the outside. In the interior of the backing layer 2, large pores or cavities are partly formed, and therefore the backing layer has a low weight and high strength. The recess 7 has a depth T in the backing layer 2, and therefore the thickness D of the backing layer 2 in the region of the recess 7 is reduced to a residual thickness R. The surface of a first region of the decorative layer 6 on the visible side, the region lying directly above a recess 7, forms a common plane together with a second region which lies directly adjacent to the first region on the decorative layer 6, and therefore the decorative layer on the visible side of the backing layer does not have any recesses or jumps in level in a region opposite the recesses.

(8) FIGS. 3a to 3d show various variant shapes of the predetermined breaking points or recesses 7. The recesses can be formed in different ways depending on the predetermined breaking force sought, the predetermined breaking profile and the residual thickness sought.

(9) In FIG. 3a, the recesses 7 are of round design in their basic shape or are of cylindrical design in their geometry. The width B corresponds to the length L as diameter X, and the individual recesses 7 are spaced from one another at a constant distance A.

(10) FIG. 3b shows recesses of a multiplicity of predetermined breaking points, wherein the recesses are formed in a pyramid-shaped manner, stretched along the predetermined breaking line.

(11) In FIG. 3c, the recesses are of oval design and are spaced from one another with distances A1, A2 and A3 becoming uniformly smaller.

(12) FIG. 3d shows recesses of a multiplicity of predetermined breaking points which are formed hexagonally in their basic shape and taper from the visible side in the direction of the rear side such that a respective bottom surface of the respective recess 7 furthermore has a hexagonal shape which is, however, smaller than the hexagonal basic shape. By tapering in a section transversely with respect to the predetermined breaking line, the recess is of trapezoidal design. In each case one edge of the hexagonal shape on each side of the hexagonal shape in the longitudinal direction faces in the direction of the predetermined breaking line.

(13) FIGS. 4a to 4c each show a state of the backing layer 2 during the production of the lining element 1 by the injection molding integral foam method as a cross section through the backing layer 2.

(14) In FIG. 4a, the backing layer 2 can be seen after injection of the material of which the backing layer 2 is composed. The backing layer 2 forms a welding rib 8 on its rear side opposite the recess 7 and, on the welding rib 8, a notch 9 which at least partly encircles the predetermined breaking region.

(15) In FIG. 4b, the backing layer 2 from FIG. 4a has been compressed by the die by the first die side and the second die side having been brought toward each other. In the process, the projections dip into the welding rib 8 in order to produce the recesses 7. The projections which dip into the welding rib 8 can be designed to be longer than projections which do not dip into the welding rib 8, since the projections would otherwise collide with the opposite die side.

(16) In FIG. 4c, the cavity in which the backing layer 2 from FIG. 4b is arranged in a die has been enlarged. By means of chemical or physical blowing agents, the backing layer 2 in the cavity is expanded or foamed. As the cavity increases, those inner regions of the backing layer 2 which have not yet solidified expand. The expansion of the inner regions gives rise to the internal foam structure. Furthermore, the profile of the sought breaking profile 10 through the backing layer 2 can be seen in FIG. 4c in the cross section of the backing layer 2. The sought breaking profile 10 extends from the notch 9 through the backing layer 2 into the recess 7. The predetermined breaking region 3 lies on the right of the breaking profile 10 in FIG. 4c, and the surrounding region 5 lies on the left of the breaking profile 10.

(17) The invention is not restricted in its embodiment to the preferred exemplary embodiments indicated above. On the contrary, a number of variants are conceivable which use the solution illustrated even in fundamentally different embodiments. For example, the multiplicity of projections which are arranged on the first die side could be designed as retractable and extendable pins which can be retracted and extended into the first die side such that the distance between the first die side and the second die side can be freely selected and the retractable and extendable pins can be freely set in their height in relation to the first die side.

(18) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.