Grid assembly for an air opening of a motor vehicle

Abstract

Grid assembly for an air opening of a motor vehicle (10), which has a grid (30) and a frame (23) for the grid (30), which grid (30) has a border (31) and defines a grid surface (32) which is provided between a first area (33) and a second area (34) opposite the first area (33), which frame (23) has a first section (40) and a second section (60), which together form a receptacle for the edge (31) of the grid (30), which first section (40) is formed from a first plastic and which second section (60) is formed from a second plastic, where the first plastic is harder than the second plastic, which first section (40) has a first base area (41) and which second section (60) has a second base area (61), which first base area (41) and which second base area (61) have contact with each other in a connecting area (70), wherein the first base area (41) and the second base area (61) are firmly connected to each other in the connection area (70), and wherein the first base area (41) and the second base area (61) are firmly connected to each other in the connection area (70) by an injection molding connection.

Description

[0001] The invention relates to a grid assembly for an air opening, in particular in the front part of a motor vehicle, a motor vehicle and a method for producing a grid assembly.

[0002] Due to legal requirements, an object with a specified diameter may not be inserted into air vents in the front area (front end). However, for thermal and aesthetic reasons, these vents must be made larger. To comply with legal requirements, louvers are inserted into the vents to prevent the object from being inserted. Typically, a grille is inserted into the vent for this purpose.

[0003] Typically, a grille is integrated using a sandwich construction consisting of two frames and a grille. The front support frame forms the transition to the front fairing and is bolted to the second, rear frame, sandwiching the grille between them.

[0004] With the sandwich construction, the front support frame is first snapped or clipped into the front fairing. Then, the metal grille and the rear support frame are inserted. Finally, the three components are secured with a few screws or U-clamps. This complex and time-consuming assembly process is acceptable for low-volume series. For larger production runs, this procedure is uneconomical.

[0005] DE 10 2004 020 085 A1 describes a method for producing a plastic-encapsulated lead frame on which components are provided. This lead frame is embedded in a housing.

[0006] DE 10 2014 210 480 A1 shows a metal stamping grid overmolded with plastic. An adhesive material, such as an adhesive, can be applied to the stamping grid.

[0007] DE 10 2007 022 385 A1 describes a hybrid manufacturing process in which a sheet metal component and a plastic insert are first manufactured separately. A plastic component is then molded onto the plastic insert using two-component injection molding.

[0008] DE 43 21 969 A1 shows a synthetic resin framework consisting of a grid part and a frame part surrounding the grid part, wherein the frame part is manufactured in a sandwich construction.

[0009] US 2002 / 0171169 A1 shows a method for producing a plastic layer on a metal plate.

[0010] DE 10 2016 113 880 A1 shows a panel for a motor vehicle, wherein the panel comprises at least a first panel part and a protective grille, wherein the protective grille has a central viewing area and a circumferential molded part, and wherein the first panel part is joined to the molded part away from the viewing area.

[0011] DE 10 2009 027 475 A1 shows an air guiding device with two air guiding parts.

[0012] DE 20 2013 002 705 U1 shows a motor vehicle hood with a structure.

[0013] DE 2 229 782 A shows a vehicle with a body end section made of rubber or plastic.

[0014] WO 2013 / 139 992 A1 shows a filter element with a filter bellows and a support element.

[0015] DE 10 2012 012 347 A1 shows a gas filter attachment.

[0016] One object of the invention is to develop a grid composite which significantly reduces assembly time, ideally with better component performance in terms of function and weight.

[0017] This object is achieved by a grid composite according to claim 1 and claim 13.

[0018] Such a grid composite with a first section and a second section made of different plastics has clear advantages. In particular, the following advantages can result from the design, although not all advantages need to be present simultaneously: 1. Lower unit costs due to the elimination of fastening elements 2. Reduced weight due to the elimination of fastening elements 3. Lower installation costs due to the elimination of additional frames and fastening elements 4. Lower logistics and storage costs by reducing to one component 5. Reducing sources of error during assembly to a minimum 6. No creaking or squeaking due to the “rubber-mounted” tight fit of the grille 7. Higher air flow through elimination of stiffening measures such as webs 8. Possible reduction of flow leakage by applying the soft component to the air duct 9. Partial integration of the air guidance function into the soft component 10. No stress in the component assembly (thermal expansion) due to “rubber-mounted” tight fit 11. Hidden spray ejection

[0019] In the past, attempts were made to optimize the airflow to prevent leaks to the front end by attaching a sealing profile or directly injecting a soft component onto an airflow component. However, all of these concepts had a critical disadvantage: Due to the assembly tolerances, so much clearance had to be maintained that the advantage over the labyrinth seal commonly used today was quickly lost.

[0020] The invention, in which the softer component is located on the mesh, does not have this disadvantage. On the contrary, the sealing lip is pressed even more firmly against the air duct or other element as the wind increases.

[0021] A further object of the invention is to provide a motor vehicle with such a grid composite.

[0022] This object is achieved by a vehicle according to claim 14.

[0023] A further object of the invention is to provide a method for producing such a grid composite.

[0024] This object is achieved by a method according to claim 15.

[0025] In this method, the first section (40) can optionally remain in the partial mold (101) (101 = 109) and be rotated to the second partial mold (110) (rotary table tool), whereupon the grid (30) is applied to the first section (40).

[0026] A grid composite is integrated into a visible component using two-component injection molding technology, with the first component being designed as a hard component and the second component as a soft component, which reduces flow leakage by adhering to the air duct.

[0027] The design of the grid assembly as a single component is possible using a two-component mold. First, a hard component, the actual support frame, is molded. The component is then transferred into a second cavity. A metal grid is placed on the component. A second component, a soft component, is then molded. The grid is firmly connected to the support frame.

[0028] The invention is described in more detail with reference to the drawings, in which: Fig. 1 a front part of a motor vehicle with air intake openings according to the state of the art, Fig. 2 a front part of a motor vehicle with a grid composite according to the invention, Fig. 3 the lattice collar of Fig. 2 without the front part, Fig. 4 in a cross-section along the section line IV-IV of Fig. 3 the grid connection of Fig. 3, Fig. 5 a manufacturing process for a grid composite according to the invention, Fig. 6 a grille in installation position with adjacent air duct, Fig. 7 a grid assembly according to the invention in the installed position with adjacent air duct, Fig. 8 the grid composite according to the invention as a visible component, and Fig. 9 a manufacturing tool with a die pressing against the hard component.

[0029] Fig. 1 shows a bow area (front area) 20 of a motor vehicle, in particular a passenger car, according to the prior art.

[0030] A front fairing 80 is provided in which, for example, a central air inlet grille 81, two side air inlet grilles 82 and an upper air inlet grille 83 are provided as air inlets.

[0031] The central air inlet grille 81 has, for example, a front support frame 81A, a metal grille 81B, a rear support frame 81C and 18 U-brackets 81D as fastening means.

[0032] The side air intake grille 82 has a front support frame 82A, a metal grille 82B, a rear support frame 82C and 10 U-brackets 82D as fastening means.

[0033] The upper air intake grille 83 has an upper support frame 83A, a metal grille 83B, a lower support frame 83C and 23 screws 83D as fastening means.

[0034] The air intake grilles 81, 82, and 83 are thus realized as a sandwich structure, and the metal grille is clamped between two support frames. One of the frames, usually the front frame, is connected to the front fairing 80. This is therefore not a composite assembly.

[0035] This type of construction and assembly is complex.

[0036] Fig. 2 shows the front area 20 of a motor vehicle 10 with the front fairing 80 and a grid assembly 21 according to the invention.

[0037] Fig. Figure 3 shows a schematic representation of the grid assembly 21 with a grid 30 and a frame 23 for the grid 30. The frame 23 preferably extends around the entire grid 30, but it can also be formed around only a portion of the grid 30.

[0038] Fig. 4 shows a partial section through the grid assembly 21 according to the section line IV - IV of Fig. 3.

[0039] The grid 30 has an edge 31.

[0040] The grille 30 defines a grille surface 32, which is provided between a first region 33 and a second region 34 opposite the first region 33. The grille 30 and thus the grille surface 32 can be flat or curved, depending on the contour of the front fairing 80.

[0041] The frame 23 has a first section 40 and a second section 60, which together form a receptacle 24 for the edge 31 of the grid 30.

[0042] The first section 40 is formed from a first plastic, and the second section 60 is formed from a second plastic. The first plastic is preferably harder than the second plastic. Preferably, the first plastic is a hard component and the second plastic is a soft component. Preferably, the first plastic is a thermoplastic and the second plastic is a thermoplastic elastomer or elastomer.

[0043] The first plastic, for example, is a PPE - Polyphenylene ether PA 6.12 - Poly(hexa-methylene-dodecane-diamide)

[0044] The second plastic is, for example, a SBR - Styrene-Butadiene Rubber NBR - Nitrile rubber

[0045] The first section 40 and the second section 60 are connected to each other in a connecting region 70. In the preferred connection by means of multi-component injection molding, the expert refers to compound adhesion. This compound adhesion leads to a bond strength of the composite 40, 60, and possibly 30.

[0046] The first section 40 has a base region 41, and the second section 60 has a base region 61. The base regions 41, 61 are arranged adjacent to one another, and the connecting region 70 is provided between the base regions 41, 61. In other words, the first base region 41 and the second base region 61 are in contact with each other in a connecting region 70.

[0047] Preferably, the first base region 41 and the second base region 61 are firmly connected to one another in the connecting region 70, particularly preferably by bonding, as can be achieved in particular by multi-component injection molding. The connecting region 70 can also extend into the region of the grid 30 by the soft component extending through a grid opening of the grid 30 to the first base region 41. This provides a particularly stable connection of the grid 30 in the receptacle formed by the first section 40 and the second section 60.

[0048] The second base region 61 extends inward from the edge 31 of the grid 30 along a lateral region of the grid 30. This enables a good fit of the grid 30 in the frame 23 and, if necessary, a bond between the second base region 61 and the grid 30.

[0049] The second base region 61 is also arranged at the outer edge of the rim 31. This enables good damping when the grating 30 moves toward this region, since the second base region 61 is made of a softer and preferably elastic material.

[0050] Preferably, the first section 40 and the second section 60 are each formed from a plastic, wherein the first section 40 is harder than the second section 60.

[0051] The first section 40 and the second section 60 enclose the edge 31 of the grid 30 at least in part.

[0052] The grille 30 allows air to flow through the grille assembly 21. The first region 33 is preferably provided as the inflow region 33, and the second region 34 as the outflow region. Air can flow from the inflow region 33 via the grille 30 to the outflow region 34, as indicated by an arrow 25.

[0053] The first section 40 has a first projection 42 and a second projection 43, each extending toward the first region 33. The second section 60 has a third projection 62, which extends toward the second region 34.

[0054] The projections 42, 43 and 62 may also be referred to as lips, and they preferably run around the entire grid 30, or at least partially around it.

[0055] The first projection 42 preferably serves as an air guide. Its cross-section preferably tapers with increasing distance from the grille 30 to reduce weight.

[0056] The second projection 43 is arranged outside the first projection 42 and serves for mounting the grid assembly 21 on the motor vehicle 10 of Fig. 2. It is advantageous for structural stability that the first section 40 is harder than the second section 60.

[0057] The first projection 42 and the second projection 43 together have a U-shaped profile in cross-section, and this ensures good stability of the first section 40.

[0058] The third projection enables air guidance in the second region 34 of the grille 30. Preferably, the third projection 62 tapers in cross-section with increasing distance from the grille 30, and thereby a deformability of the third projection 62 is increased.

[0059] The grid 30 is preferably designed as a metal grid. This enables high stability of the grid assembly 21.

[0060] Fig. 5 shows a method for producing the grid composite 21.

[0061] On the left (A) is a first injection mold 101 with a first partial mold (die) 105 and a second partial mold (core) 106, which together form a first cavity (hollow space to be filled) 107.

[0062] With the first injection mold 101, the first section 40 is produced as a component made of a harder plastic (hard component) (B).

[0063] Subsequently, a second injection mold 102 is used with a third partial mold (die) 109 and a fourth partial mold (core) 110, which form a second cavity (cavity to be filled) 111.

[0064] Injection molds 101 and 102 can also be the same. In this case, the component remains in the die (rotary mold).

[0065] The first section 40 is inserted into the third part mold 109 (C), and the grid 30 is applied to the first section 40 (D).

[0066] Subsequently (E), the fourth partial mold 110 is placed against the first section 40 and preferably also against the grid 30, and the second cavity 111 present in the fourth partial mold 110 is filled with a softer plastic (soft component) so that the first section 40 and the second section 60 form a composite, with composite adhesion occurring between the first section 40 and the second section 60, which holds these sections 40, 60 together. This is referred to as a plastic-plastic composite. Additional composite adhesion between the first plastic and the grid 30 and / or in particular between the second plastic and the grid 30 is possible. Floating mounting of the grid 30 in the frame 23 is advantageous, in particular for damping movements of the grid.

[0067] Thus, frame 23 is manufactured using a two-component injection molding process. A multi-component injection molding process with more than two components is also possible. The finished lattice composite can also be referred to as an integrated molded part to distinguish it from a sandwich-type component.

[0068] The grid assembly 21 enables the supply of air into the interior of the motor vehicle. For this purpose, the grid assembly 21 preferably cooperates with an air duct 120, for example, a wall, inside the motor vehicle.

[0069] For efficient cooling and to avoid noise, it is advantageous if the interaction between the grille assembly 21 and the air duct 120 functions well and there is little leakage.

[0070] Fig. 6 shows various methods for sealing between the grid assembly 21 and the air duct 120.

[0071] In the left illustration, the air guide 120 has a sealing lip 122 at its end facing the grille assembly 21.

[0072] In the middle illustration, the air duct 120 has a piping 124 at its end facing the grille assembly 21.

[0073] In the right-hand illustration, the grid assembly has a projection 126 made of a hard component that extends toward the air duct 120.

[0074] The methods using the sealing lip 122 and the piping 124 have the disadvantage that, due to the assembly tolerances that must be taken into account, a large clearance must be provided between the air duct 120 and the grille assembly 21. Therefore, these methods do not have a particularly positive effect, but on the other hand, they are complex to manufacture. The method using the labyrinth 126 (in conjunction with the air duct 120) works and is relatively easy to install.

[0075] Fig. Figure 7 shows a preferred possibility for sealing between the grid assembly 21 and the air duct 120. The grid assembly 21 has the second section corresponding to Fig. 4, which is softer than the first section 40, preferably made of a soft component.

[0076] In the left picture, little air flows through the grille 30, which is indicated by a few arrows 25, and the second section 60 has largely its basic shape.

[0077] In the right-hand image, however, a large amount of air flows through the grille 30, for example, when the vehicle is traveling at high speed, as indicated by numerous arrows 25. The leakage air flow 130 increases with increasing speed, causing the relatively soft second section 60 to deform toward the air duct 120, further sealing it. It is assumed that Bernoulli's law, according to which a higher flow velocity is associated with a reduction in pressure, is responsible for this.

[0078] With increasing speed, the deformation leads to an increasing seal between the air guide 120 and the second section 60. It is advantageous that the second section 60 (deformation) is softer than the first section 40 (assembly).

[0079] Fig. 8 shows what a viewer 142 sees when the grid assembly 21 is arranged with the grid 30 and the frame 23 in the field of view.

[0080] Since the first section 40 was manufactured in a first step, the edges, etc., can be produced with good quality and without major burrs. The second section 60 is arranged on the inside of the grid assembly 21 and is therefore not directly visible. Furthermore, the second section 60 is offset slightly outward from the first section (relative to the grid 30), so that the area 140 is not visible. In other words, the first section 40 extends further inward relative to the grid 30 than the second section 60.

[0081] The design of the grid assembly 21 makes it possible to use the grid assembly 21 directly as a visible component in the motor vehicle 10.

[0082] Manufacturing the grid assembly 21 using a one-component injection molding process would result in material bulging or a broad burr in the area of ​​the grid 30, since a good seal in the area of ​​the grid 30 is difficult to achieve with the injection mold. Such bulging is visually disturbing. Therefore, a grid assembly 21 produced in this way would not be suitable for use as a visible component.

[0083] Fig. 9 shows an embodiment for the production of the grid composite 21 according to Fig. 5, Step E.

[0084] It can be seen that the fourth partial mold 110 rests against both the first section 40 and the grid 30, with a part of the grid 30 protruding into the cavity. This allows the plastic for the second section to form a bond with both the first section 40 and the grid 30. It can also be seen that the region 140 (cf. Fig.8) is located further outward on the grid 30 than the first section 40, so that the area in which the second section 60 is molded is located further outward relative to the grid 30. As a result, the first section 40 determines the visual impression when viewed from the outside, and a shapely grid assembly 21 can be achieved.

[0085] In other words, the grille is integrated into a visible component using two-component injection molding technology, with the second component being designed as a soft component, which significantly reduces flow leakage by adhering to the air duct.

[0086] Two-component injection molding technology makes it possible to place the material extrusion in a non-visible area. This is achieved by pressing the core against the inserted part, the hard component, in the second cavity, thus assuming the sealing function.

[0087] Naturally, many variations and modifications are possible within the scope of the invention.

Claims

[1] Grid assembly for an air opening of a motor vehicle (10), which has a grid (30) and a frame (23) for the grid (30), which grid (30) has an edge (31) and defines a grid surface (32) which is provided between a first region (33) and a second region (34) opposite the first region (33), which frame (23) has a first section (40) and a second section (60), which together form a receptacle for the edge (31) of the grid (30), which first section (40) is made of a first plastic and which second section (60) is made of a second plastic, where the first plastic is harder than the second plastic, which first section (40) has a first base region (41) and which second section (60) has a second base region (61), which first base region (41) and which second base region (61) are in contact with each other in a connecting region (70), wherein the first base region (41) and the second base region (61) are firmly connected to one another in the connecting region (70), and wherein the first base region (41) and the second base region (61) are firmly connected to one another in the connecting region (70) by an injection-molded connection. [2] Grid composite according to claim 1, wherein the first base region (41) and the second base region (61) are firmly connected to one another in the connecting region (70) by bonding. [3] Grid assembly according to one of the preceding claims, wherein the grid (30) comprises a metallic material. [4] Grid assembly according to one of the preceding claims, wherein the first portion (40) extends further inward relative to the grid (30) than the second portion (60). [5] Grid assembly according to one of the preceding claims, wherein the second base region (61) extends inwardly from the edge (31) of the grid (30) along a lateral region of the grid (30). [6] Grid composite according to one of the preceding claims, in which the second base region (61) is arranged at least in regions on the outer edge of the rim (31). [7] Grid assembly according to one of the preceding claims, wherein the first portion (40) has a first projection (42) which extends into the first region (33) to enable air guidance there. [8] Grid assembly according to claim 7, wherein the first projection (42) tapers in cross-section with increasing distance from the grid (30). [9] Grid assembly according to claim 7 or 8, wherein the first portion (40) has a second projection (43) which extends into the first region (33) and is arranged outside the first projection (42) to enable mounting of the grid assembly (21) on a motor vehicle (10). [10] Grid assembly according to claim 9, wherein the first projection (42) and the second projection (43) together have a U-shaped profile in cross section. [11] Grid assembly according to one of the preceding claims, wherein the second portion (60) has a third projection (62) which extends into the second region (34) to enable air guidance there. [12] Grid assembly according to claim 11, wherein the third projection (62) tapers in cross-section with increasing distance from the grid (30) in order to increase a deformability of the third projection (62). [13] Grid assembly for an air opening of a motor vehicle (10), which has a grid (30) and a frame (23) for the grid (30), which grid (30) has an edge (31) and defines a grid surface (32), which is provided between a first region (33) and a second region (34) opposite the first region (33), which frame (23) has a first section (40) and a second section (60), which together form a receptacle for the edge (31) of the grid (30), which first section (40) is made of a first plastic and which second section (60) is made of a second plastic, wherein the first plastic is harder than the second plastic, which first section (40) has a first base region (41) and which second section (60) has a second base region (61), which first base region (41) and which second base region (61) are in contact with each other in a connecting region (70), wherein the first base region (41) and the second base region (61) are firmly connected to one another in the connecting region (70), and wherein the grid (30) comprises a metallic material. [14] Motor vehicle with a grid assembly (21) according to one of the preceding claims, in which the grid assembly (21) is installed as a visible component. [15] Method for producing a grid assembly, which grid assembly comprises a grid (30) and a frame (23) for the grid (30), which grid (30) has an edge (31), which frame (23) has a first section (40) and a second section (60), which together form a receptacle for the edge (31) of the grid (30), which first section (40) is made of a first plastic and which second section (60) is made of a second plastic, where the first plastic is harder than the second plastic, which procedure comprises the following steps: A) The first section (40) is manufactured by plastic injection molding B) The first section (40) is placed in a first part mold (109) and the grid (30) is applied to the first section (40) C) A second partial mold (110) is positioned relative to the first partial mold (109) in such a way that it has contact with both the grid (30) and the first section (40) and together with them defines a cavity (111) D) The second section (60) is manufactured in the cavity (111) by plastic injection molding.

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