METHOD FOR MANUFACTURING A HEATED INTERIOR PANEL AND METHOD FOR MANUFACTURING AN INTERIOR PANEL
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- LISA DRAXLMAIER GMBH
- Filing Date
- 2022-02-14
- Publication Date
- 2026-07-09
AI Technical Summary
Existing methods for producing interior trim parts with visible heating elements, such as armrests, result in increased costs and reduced heating capacity due to the use of additional foam layers or visible heating strands, which impair the aesthetic appearance.
A method involving a flat heating element embedded as a foam mat within a foaming tool, where the heating element is back-foamed on one side only, ensuring it remains flush with the visible surface and avoids additional foam layers, using a softer foam material to maintain heating efficiency and aesthetic quality.
The method produces interior trim parts with hidden heating elements, reducing material and process costs while maintaining heating performance and enhancing the material's softness and appearance.
Smart Images
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Abstract
Description
Technical field
[0001] The present invention relates to a method for manufacturing an interior trim part which, when in use, has a visible side and a flat heating element for heating the visible side. The invention further relates to the use of the interior trim part manufactured in this way as an armrest in a vehicle, such as a motor vehicle. State of the art
[0002] For example, interior trim parts are known from DE 10 2014 005 190 A1, which are used, for example, in vehicles as heated armrests, steering wheels, or the like. Such an interior trim part typically has at least one layer of foam to provide cushioning for its intended use. The heating of such an interior trim part is achieved via a heating element, usually a flat surface consisting of a fleece with heating wires attached to it.
[0003] In practice, it has been shown that heating wires that protrude even slightly from the fleece become visible on the interior trim panel unless additional design measures are taken. One possible design measure is to provide an additional layer of cut foam between the fleece and the decorative material forming the visible surface. The disadvantage of this is the increased processing and material costs due to the additional cut foam. Another possibility is proposed by the aforementioned DE 10 2014 005 190 A1, namely, encasing the flat heating element with a foam material. However, this can impair the heating performance of the interior trim panel, as encasing the flat heating element inevitably creates an additional layer of foam on the visible surface of the interior trim panel. Description of the invention
[0004] One object of the invention is therefore to provide an interior fitting, using the simplest possible means, on the visible side of which a heating element is at least slightly visible and which can be heated as well as possible.
[0005] The problem is solved by the subject matter of the independent claims. Advantageous embodiments of the invention are specified in the dependent claims, the description, and the accompanying figures.
[0006] A method for manufacturing an interior trim panel with a visible side and a flat heating element is proposed. The interior trim panel produced by this method, or possibly by a subsequent process, can be used, for example, as an armrest on a door panel, a center console, or similar. In this configuration, the interior trim panel can also be referred to as a heated interior trim panel. The method comprises the following steps, which can be carried out in the specified order or in a different order. A carrier element is provided. Furthermore, the flat heating element, in the form of a foam mat or heating mat, is arranged in a foaming tool such that the first flat surface of the heating element, facing the visible side of the interior trim panel to be manufactured, rests against an inner surface of the foaming tool.Furthermore, a first layer of foam material is introduced into the foaming tool onto the second flat side of the flat heating element, opposite the first flat side, in such a way that the flat heating element is only foamed over on the second flat side. It is also intended that the first layer of foam material bonds with the support element and the flat heating element.
[0007] In other words, the flat heating element is provided as a foam mat or heating mat and used in the interior trim panel being manufactured. Furthermore, it is only foamed from one side, not from both sides, since the flat heating element rests against the inner surface of the foaming tool. Thus, little or no foam material reaches the first flat side of the heating element, and it remains largely untreated. Consequently, compared to conventional methods, this avoids the situation where a cut foam or other foam layer between the flat heating element and the visible surface acts as an insulator and reduces heating performance.In particular, compared to the use of a fleece with heating wires attached to it, the foam mat used in the proposed method is less noticeable or even invisible on the visible surface, since the foam mat, unlike the fleece, has a lower hardness, for example, compression strength, or is softer. Furthermore, the foam mat allows for greater softness and can therefore yield more, which enhances the material appearance of the interior trim component.
[0008] The "foam mat," which can also be called a "foamed mat," can be understood in this context as a mat-shaped element made of a suitable foam material that is softer and / or harder than, in particular, a non-woven material. Furthermore, the "foam mat" can be understood as a mat-shaped element with two opposing, at least essentially flat surfaces without any raised areas, i.e., with integrated rather than surface-mounted heating elements.
[0009] The "support element" in this context can be understood as a structural element in the form of, for example, a door panel or a part thereof, in particular an armrest, a center console or a part thereof, in particular a center armrest, or similar. The support element can be made of a metallic material, but preferably of a plastic material such as polycarbonate (PC) or acrylonitrile butadiene styrene copolymer (ABS). The support element can be manufactured and provided, for example, by means of an injection molding process. The support element can therefore be prefabricated.
[0010] According to a further development of the proposed method, the flat heating element can be laminated with a decorative material in such a way that the first flat surface of the heating element is in direct contact with the decorative material. The decorative material then forms the visible surface of the interior trim panel. The decorative material can be, for example, leather, imitation leather, or a similar material. Lamination can be carried out, for example, by press lamination, which represents a manufacturing process that is at least largely fully automated. This enables particularly efficient production of the interior trim panel, whereby an additional foam layer can be eliminated by encasing the flat heating element in foam or by providing an additional cut foam layer.
[0011] In a further development of the proposed method, the planar heating element can be provided as a foam mat with heating elements, e.g., heating wires, embedded in a second foam material. Preferably, a plurality of heating elements, i.e., at least two or more, is provided. The heating elements can be supplied with electrical energy via an electrical conductor, a supply line, and thus produce a heating effect. In this context, "embedded" can be understood to mean that the heating elements are arranged within the foam material of the foam mat in such a way that at least the first planar side or both planar sides of the foam mat are at least substantially flat or planar, i.e., have no protrusion with respect to the heating elements.It is also possible that the heating elements are embedded in the foam material of the foam mat in a sandwich-like manner, meaning that they are not exposed on the first flat side of the heating element, but rather covered by the foam material, preferably the same foam material. This makes it particularly easy to prevent the heating elements from showing through on the visible side of the interior trim panel.
[0012] According to a further development of the proposed method, the planar heating element can be provided such that the heating elements are arranged flush with or recessed into the first planar surface. In other words, the heating elements of the foam mat can be recessed into the foam material of the planar heating element to such a depth relative to the first planar surface that they extend at most into a plane defined by the first planar surface, but do not protrude beyond it, thus preventing the heating elements from protruding on the first planar surface. This makes it particularly easy to prevent the heating elements from showing through on the visible side of the interior trim panel.
[0013] In a further development of the proposed method, the first foam material applied to the second flat surface of the flat heating element can be polyurethane foam (PUR foam). It has been shown that the PUR foam bonds particularly well with the second foam material of the foam mat. The first foam material can be applied using a so-called one-shot process, in which all components are mixed without solvents, resulting in particularly efficient manufacturing.
[0014] According to a further development of the proposed method, the planar heating element can have a thickness of approximately 1 mm to approximately 4 mm, preferably approximately 1 mm. The heating elements of the planar heating element can be arranged within the 1 mm to 4 mm overall outer dimension, so that they do not increase the outer dimensions of the foam mat. Furthermore, the softness or hardness, in particular the compression hardness, of the foam mat can be adjusted by varying the thickness.
[0015] In a further development of the proposed method, the first foam material can be introduced using front foaming, in which the first foam material bonds directly and materially to the carrier element. This allows for particularly efficient manufacturing of the interior trim component.
[0016] According to a further development, the flat heating element can be inserted into a first tool side of the foaming tool, and the support element can be inserted into a second tool side of the foaming tool. The flat heating element, with the first foam material applied to its first flat surface, is connected to the support element by closing the first and / or second tool side, i.e., by bringing the two tool sides together. This allows for a particularly simple manufacturing process for the interior trim part.
[0017] In a further development process, the carrier element can be provided with a cutout for routing the electrical conductor of the flat heating element. The electrical conductor is routed at least partially within the foaming tool, and a functional test of the electrical conductor and / or the flat heating element is performed during the foaming process. For example, an end facing away from the flat heating element can be connected to a functional test device, e.g., plugged into it or similar, suitable for continuity testing or other functional testing. This can be done, for example, during the reaction of the foam material, e.g., an exothermic reaction, and / or during the foaming, curing, etc., of the foam material, thus saving time in the manufacturing process.
[0018] Furthermore, the use of the interior trim part manufactured according to the above-described method in one or more of the described further developments as a heated armrest in a vehicle is proposed. The interior trim part manufactured according to the proposed method enables high product quality, which can also be achieved with a comparatively simple process, since no heating element or parts thereof, such as heating elements, are visible on the interior trim part.
[0019] Furthermore, a method for manufacturing an interior trim panel in at least two different versions is proposed. The interior trim panel is optionally available in a first version as a heated panel with a visible surface and a flat heating element, and in a second version as an unheated panel with a visible surface. The method comprises the following steps. First, it is determined whether the interior trim panel is to be manufactured or provided in the first or the second version. Additionally, a support element with a cutout for optionally guiding an electrical conductor of the flat heating element is provided. If it is determined that the interior trim panel is to be provided in the first version, the method is carried out in the following steps: Arranging the flat heating element as a foam mat in a foaming tool such that the flat heating element, with a first flat side facing the visible side of the interior trim part to be produced, rests against an inner surface of the foaming tool; Introducing a first foam material into the foaming tool onto a second flat side of the flat heating element opposite the first flat side, such that the flat heating element is only foamed behind on the second flat side; the first foam material connects with the support element and the flat heating element. However, if it is determined that the interior trim part is to be provided in the second version variant, the procedure is carried out with the following steps: Introducing an initial foam material into a foaming tool; the first foam material bonds with the support element, and the notch of the support element is filled with the first foam material.
[0020] In other words, a uniformly designed carrier element is provided for both production variants, resulting in a single, unified part without any variations. If the first, heated version of the interior trim panel is to be produced, the process described above is carried out in one or more of the described refinements, so that a heated interior trim panel can then be produced or provided using the uniformly provided carrier element. However, if the second, unheated version of the interior trim panel is to be produced, the same carrier element is used, but the cutout is simply filled with foam. This means that subsequent processes, such as laminating the foam-backed carrier element, do not need to be modified compared to the first version of the interior trim panel.The proposed method thus enables a variety of variants of the interior trim part, in which the support element only needs to be available in a single, uniform design variant and the manufacturing process remains essentially the same, or at least does not need to be modified in subsequent processes.
[0021] Further features, advantages and possible applications of the invention will become apparent from the following description of advantageous embodiments and the accompanying figures. List of characters
[0022] An advantageous embodiment of the invention is explained below with reference to the accompanying figures. These show: Fig. Figure 1 shows an exploded view of a heated interior lining part that can be manufactured using a method according to one embodiment. Fig. Figure 2 shows a top view of a heated interior lining part which can be manufactured using a method according to one embodiment. Fig. Figure 3A shows a rough schematic of an arrangement of heating elements on, for example, a non-woven material, as used in conventional methods for manufacturing heated interior lining parts. Fig. Figure 3B shows a schematic arrangement of heating elements embedded in a foam material to form a foam mat, as used in a method according to an embodiment of a method for manufacturing heated interior trim parts. Fig. Figure 4 shows a schematic representation of a foaming tool with a flat heating element arranged therein, as used in a method according to an embodiment of a method for manufacturing heated interior trim parts.
[0023] The figures are merely schematic representations and serve only to illustrate the invention. Identical or equivalent elements are consistently identified by the same reference numerals. Detailed description of preferred embodiments
[0024] Fig. Figure 1 shows an exploded view of a heated interior trim part 100, which can be manufactured using a method according to one embodiment. For example, the interior trim part 100 can be used as an armrest on a door panel, a center console, or the like in a vehicle, aircraft, or similar. The interior trim part 100 has a visible side that, when in use, faces the vehicle or aircraft interior or an occupant.
[0025] The interior trim part 100 has a support element 110 as its structural element, i.e., base element. This support element 110 can be made, for example, of a plastic material such as polycarbonate (PC) or acrylonitrile butadiene styrene copolymer (ABS). The support element 110 can, for example, be manufactured by injection molding. The support element 110 can have one or more cutouts, such as a material recess, a through-hole, or similar features, which are suitable for guiding and / or routing an electrical conductor. (See exploded view according to...) Fig. 1 is the support element 110, which is the part furthest from the visible side of the interior trim part 100 and thus represents the lowest part of the same.
[0026] Furthermore, the interior trim part 100 has a foam material 120, i.e., a foam body, made of a foamed plastic material, e.g. polyurethane (PUR) or similar, which is connected to the carrier element 110, preferably by a material bond, and in Fig. 1 is arranged above the support element 110. In this application, the foam material 120 is also referred to as the “first foam material”.
[0027] Furthermore, the interior lining part 100 has a planar heating element 130 for optional heating. This element is designed as a foam mat with a plate-shaped foam body 131 made of a foam material, e.g., a foamed polymer, with embedded heating elements 132, e.g., heating wires or the like. It can therefore also be described as a foamed heating mat with embedded heating elements. The heating elements 132 are arranged flush with or recessed into a planar side of the foam body 131, which faces the visible side and is also referred to in this application as the "first planar side". The foam material, for example, has a higher softness or lower hardness than, in particular, a nonwoven material. In this application, the foam material of the planar heating element is also referred to as the "second foam material", in contrast to the first foam material 120.It should be noted that the first and second foam materials can be different, although an identical pairing of materials is also conceivable, provided that both foam materials can be bonded or adhere to each other. The planar heating element 130 has two opposing, at least substantially flat surfaces without any elevation, i.e., with heating elements 131 embedded in the foam material rather than placed on top of it. In . Fig. Figure 1 indicates that the flat heating element 130 is arranged above the foam material 120, wherein the flat heating element 130 is preferably bonded to the foam material 120, e.g. by means of front foaming. In other words, the flat heating element 130 is back-foamed with the foam material 120.
[0028] The interior trim panel 100 also features a decorative material 140, such as leather, imitation leather, or similar material, which essentially forms or is arranged on the visible side of the interior trim panel. Accordingly, the decorative material 140 is the uppermost element of the Fig. 1 of the illustrated structure, i.e., it is arranged above the flat heating element 130. From this, it can be deduced that the flat heating element 130 is in direct contact with the decorative material 140, i.e., no further element is arranged in between, such as a cut foam, which in conventional methods serves to prevent the outline of any heating elements, such as heating strands attached to a fleece.
[0029] Fig. Figure 2 shows the interior trim part 100 in a top view, in which the decorative material 140 is partially omitted for illustrative purposes only, to show that the flat heating element 130 lies directly against the decorative material 140 and its heating elements 132, e.g. heating strands or similar, do not protrude from its foam body 131.
[0030] Based on Fig. 3, which the Fig. 3A and Fig. Section 3B further clarifies that, as in Fig. 3A shows that in a conventional arrangement with a fleece and heating wires arranged on it, these would be visible in the decorative material, i.e., on the visible side of the interior trim panel. The foam mat used in the proposed interior trim panel – as shown in Fig. As shown in Figure 3B, the heating elements 132, e.g., heating wires or similar, are embedded in the foam material or the foam body 131, so that the heating wires are not arranged on top and are at least slightly or not at all visible through the decorative material 140. As shown in Fig. 3A and Fig. As indicated in 3B, the heating elements 132 are at least embedded in the foam material of the flat heating element 130 or arranged in a sandwich-like manner.
[0031] Based in particular Fig. Figure 4, which shows a foaming tool 200 with a flat heating element 130 arranged therein, now describes a method for manufacturing the inner lining part 100.
[0032] First, the carrier element 110 is provided, which, as described above, can be manufactured, for example, from a plastic material using an injection molding process. In addition, the flat heating element 130, in the form of a foam mat, is arranged in the foaming tool 200 such that its first flat surface, facing the visible side of the interior trim part 100 to be produced, rests against an inner surface of the foaming tool 200. Then, the first foam material is injected into the foaming tool 200 onto the second flat surface of the flat heating element 130, opposite the first flat surface, such that the flat heating element 130 is only foamed over on this second flat surface. In this process, the first foam material bonds with the carrier element 110 and the flat heating element 130.
[0033] The method described above also enables the production of the interior trim part 100 in at least two different versions. In a first version, it is heatable and has the flat heating element 130. In a second version, the interior trim part is unheatable and lacks the flat heating element 130.
[0034] First, it is determined whether the interior trim part 100 is to be provided in the first or the second version. This can be accomplished, for example, by evaluating the specification or order data, even automatically via computer-implemented evaluation. In addition, the support element 110 is fitted with a cutout 111 (see Fig. 1) provided for the optional routing of an electrical conductor of the planar heating element 130, as a unit independent of the specified embodiment of the inner lining part 100. If it is determined that the inner lining part is to be provided in the first embodiment, the method is carried out such that the planar heating element 130 is arranged as a foam mat in the foaming tool 200 in such a way that the planar heating element 130, with a first planar side facing the visible side of the inner lining part 100 to be produced, rests against an inner surface of the foaming tool 130 (the lower side of the foaming tool 200 according to Fig.4) The first foam material is then introduced into the foaming tool 200 onto the second flat side of the flat heating element 130, opposite the first flat side, such that the flat heating element 130 is only foamed over on its second flat side, bonding the first foam material with the carrier element 110 and the flat heating element 130. However, if it is determined that the inner lining part 100 is to be provided in the second embodiment, the procedure is carried out such that the first foam material is introduced into the foaming tool 200 without the flat heating element 130 being used or inserted into the foaming tool 200 at all. The first foam material then bonds with the carrier element 100, and the cutout 111 of the carrier element 110 is filled with the first foam material. REFERENCE MARK LIST 100 Interior trim part 110 support element 120 (first) foam material 130 flat heating element 131 (second) foam material 132 Heating element 140 decorative materials 200 foaming tools QUOTES INCLUDED IN THE DESCRIPTION
[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature
[0000] DE 102014005190 A1 [0002, 0003]
Claims
[1] Method for manufacturing an interior trim part (100) with a visible side and a planar heating element (130), comprising the steps: Providing a support element (110), Arranging the planar heating element (130) as a foam mat in a foaming tool (200) such that the planar heating element (130) with a first planar side, which is facing the visible side of the interior lining part (100) to be produced, rests against an inner surface of the foaming tool (200), Introducing a first foam material into the foaming tool (200) onto a second flat side of the flat heating element (130) opposite the first flat side, such that the flat heating element (130) is only foamed behind on the second flat side, wherein the first foam material connects with the support element (110) and the flat heating element (130). [2] Method according to claim 1, wherein the planar heating element (130) is covered with a decorative material (140) such that the first planar side of the planar heating element (130) is directly adjacent to the decorative material (140) which forms the visible side of the inner lining part (100). [3] Method according to claim 1 or 2, wherein the planar heating element (130) is provided as a foam mat with heating elements (132) embedded in a second foam material. [4] Method according to claim 3, wherein the planar heating element (130) is provided such that the heating elements (132) are arranged flush with or recessed to the first planar side. [5] Method according to one of the preceding claims, wherein the planar heating element (130) has a thickness of about 1 mm to about 4 mm, preferably about 1 mm. [6] Method according to one of the preceding claims, wherein the first foam material is introduced by means of front foaming, in which the first foam material directly bonds to the carrier element (110). [7] Method according to one of the preceding claims, wherein the planar heating element (130) is inserted into a first tool side of the foaming tool (200), the support element (110) is inserted into a second tool side of the foaming tool (200) and the planar heating element (130) is connected to the support element (110) with the first foam material applied to its first planar side by closing the first and second tool sides. [8] Method according to one of the preceding claims, wherein the carrier element (110) is provided with a notch (111) for guiding an electrical conductor of the planar heating element (130), the electrical conductor is guided within the foaming tool (200) and a functional test of the electrical conductor and / or the planar heating element (130) is carried out during the foaming process. [9] Use of the interior trim part (100) produced according to the method according to one of the preceding claims as a heated armrest in a vehicle. [10] Method for manufacturing an interior trim part (100) in at least two different embodiments, wherein the interior trim part (100) in a first embodiment is heatable with a visible side and a planar heating element (130) and the interior trim part (100) in a second embodiment is unheatable with a visible side, and wherein the method comprises the following steps: Determine whether the interior trim part (100) is to be provided in the first or the second version variant, Providing a support element (110) with a notch (111) for optionally guiding an electrical conductor of the planar heating element (130), where, if it is determined that the interior trim part (100) is to be provided in the first embodiment variant, the procedure comprises the following steps: Arranging the planar heating element (130) as a foam mat in a foaming tool (200) such that the planar heating element (130) with a first planar side, which is facing the visible side of the interior lining part (100) to be produced, rests against an inner surface of the foaming tool (200), Introducing a first foam material into the foaming tool (200) onto a second flat side of the flat heating element (130) opposite the first flat side, such that the flat heating element (130) is only foamed behind on the second flat side, wherein the first foam material connects with the support element (110) and the flat heating element (130), and where, if it is determined that the interior trim part (100) is to be provided in the second embodiment variant, the procedure comprises the following steps: Introducing an initial foam material into a foaming tool (200), wherein the first foam material bonds with the carrier element (110), and wherein the notch (111) of the support element (110) is filled with the first foam material.