Method for manufacturing a plastic component, plastic component and its use

Abstract

Method for manufacturing a plastic component (1), comprising at least two plate-shaped sub-bodies (2.1, 2.2, 2.3) which are arranged layer by layer on top of each other and each have at least one recess (3) on their mutually facing sides, wherein the recesses (3) jointly define a channel (4) and wherein the sub-bodies (2.1, 2.2, 2.3) are each manufactured in a thermoplastic foam injection molding process and are subsequently joined layer by layer to form the plastic component (1).

Description

Technical area

[0001] The invention relates to a method for producing a plastic component, the plastic component produced by the method and its use. State of the art

[0002] The production of plastic components is well known. One method used to manufacture plastic components is injection molding. In injection molding, the plastic is first plasticized and then injected under pressure into the cavity of the injection mold. After the material has solidified in the cavity, the injection mold is opened and the finished plastic component is removed. This process allows for large quantities to be produced cost-effectively.

[0003] However, it should be noted that the melt flow behavior during injection should be as laminar as possible in order to obtain plastic components with the best possible dimension.

[0004] For this purpose and to ensure the most uniform cooling and shrinkage possible, it is of crucial importance that the plastic components produced by the process have the most uniform wall thickness possible.

[0005] To improve the dimensional accuracy and surface quality of the plastic component, it is possible to allow material to flow into the mold cavity through a process known as post-pressing, thereby improving shrinkage and the surface quality of the plastic component. Post-pressing is an additional step and therefore lengthens and increases the cost of the manufacturing process.

[0006] A thermoplastic foam injection molding process is also known. In this process, the plasticized plastic is foamed in the cavity of the injection mold using a blowing agent. This causes the foaming plastic to expand and reliably fill the mold cavity completely. The advantage of this process is that sink marks are avoided and even thicker-walled molded parts can be produced. The plastic components produced using this process are also lightweight and have a low susceptibility to warping, making them particularly dimensionally stable.

[0007] Conventional re-pressing, as previously described, is not required when using this method. Description of the invention

[0008] The invention is based on the object of showing a method by which plastic components can be manufactured from plate-shaped partial bodies of different wall thicknesses in a simple and reliable manner with dimensionally accurate results.

[0009] The plastic components should have low tolerances and be particularly sustainable.

[0010] In addition, the use of a plastic component manufactured in this way should be mentioned.

[0011] This object is achieved according to the invention by a method according to claim 1. The claims directly or indirectly referring back to claim 1 refer to advantageous developments of the method. Furthermore, the object is achieved by a plastic component according to claim 5.

[0012] The use of such a plastic component is mentioned in claim 6.

[0013] To achieve the object, a method for producing a plastic component is provided, comprising at least two plate-shaped partial bodies which are arranged layer by layer on top of one another and each have at least one recess on their mutually facing sides, wherein the recesses together delimit a channel and wherein the partial bodies are each produced in a thermoplastic foam injection molding process and are then connected to one another layer by layer to form the plastic component.

[0014] Particularly for plastic components that are constructed layer by layer from several plate-shaped sub-assemblies, high dimensional accuracy of the sub-assemblies is particularly important. Due to the layered construction, manufacturing-related tolerances of the individual sub-assemblies add up, so the tolerances of the sub-assemblies must be very small in order to achieve a dimensionally accurate, layered plastic component. The thermoplastic foam injection molding process is well suited for this.

[0015] The greater the variation in the thickness of the individual components, the better the thermoplastic foam injection molding process is suited for producing layered plastic components. These varying thicknesses can be caused by recesses in the components. These recesses can be formed by depressions or perforations. By producing the components using the thermoplastic foam injection molding process, such varying wall thicknesses along the flow path are virtually irrelevant in the production of the components, in contrast to the manufacturing processes previously used, such as the conventional injection molding mentioned above.

[0016] The dimensionally accurate partial bodies produced by the thermoplastic foam injection molding process each have connecting surfaces that are also particularly dimensionally accurate and have a good level of flatness, whereby the connecting surfaces do not have any sink marks or defects due to the manufacturing process.

[0017] The process, particularly the simple and precise manufacture of the resulting components, provides the designer with considerable design freedom in the wall thickness of the respective parts and a free choice of injection point. Shrinkage that typically occurs in the mold cavity is automatically compensated for by foaming the material during the cooling phase, without the need for additional pressure. This results in consistent shrinkage values ​​throughout the entire part despite different wall thicknesses. The parts produced in this way and the plastic component manufactured from the stacked parts thus achieve the highest achievable precision.

[0018] The thermoplastic foam injection molding process has previously been used to achieve material savings in the component to be manufactured.

[0019] In contrast, this method was not used to produce stack-like plastic parts comprising at least two plate-shaped partial bodies which are arranged one above the other in layers and connected to one another, wherein the partial bodies together define a channel.

[0020] For such plastic parts, it is essential that the channel structures of the sub-assemblies be congruent. This places high demands on the injection moldability of significant wall thickness changes within the supporting bodies and on the shape / position tolerances of the surface structures of adjacent sub-assemblies in the layered structure.

[0021] Depending on the specific circumstances of the application, it may be provided that the partial bodies produced with particularly high dimension accuracy using the process described above are subjected to further processing after their production and before the layer-by-layer joining to form the plastic component.

[0022] Following their production, the components can be provided with an electrically conductive coating. Such a coating is necessary, for example, to conduct electromagnetic waves.

[0023] For this purpose, the partial bodies can be metallized after their production.

[0024] To connect the sub-bodies arranged in layers on top of each other, the metallized sub-bodies can be soldered together to form the plastic component.

[0025] The coating may be different and have special properties, such as good sealing properties, high surface quality or good wear resistance against abrasive media.

[0026] The coated parts can be connected to each other in a suitable manner, for example by gluing, welding, riveting or snap-on connections.

[0027] Furthermore, the invention relates to a plastic component, produced by the thermoplastic foam injection molding process described above, comprising at least two plate-shaped partial bodies which are arranged one above the other in layers and each have at least one recess on their mutually facing sides, wherein the recesses together delimit a channel.

[0028] Such a channel can be used, for example, to direct and control any media, material and energy flows.

[0029] In particular, the channel can be used to conduct electromagnetic waves. The plastic component is then designed as a waveguide antenna.

[0030] In such cases, the duct must be particularly dimensionally accurate. Even minor dimensional deviations in the mutual alignment of the facing recesses, such as a very slight offset, can cause the duct system and the associated mass and energy flows to no longer function satisfactorily.

[0031] The plastic component can thus be used as a transport and control system for material, energy and information flows, in particular as a waveguide antenna.

[0032] The plastic component can also be used as a cell element in an electrolyzer. In such a case, the plastic component has comparatively large dimensions, so high dimensional accuracy due to its manufacturing process is particularly advantageous.

[0033] The plastic component can alternatively be used as a control block for hydraulic fluids. Short description of the drawing

[0034] Two embodiments of the plastic component according to the invention are described below with reference to Fig. 1 and Fig. 2 is explained in more detail.

[0035] These show in schematic representation: Fig. 1 shows a first embodiment of a plastic component with three plate-shaped partial bodies which are arranged in layers one above the other, Fig. 2 a second embodiment. Implementation of the invention

[0036] In the Fig. 1 and Fig. 2 shows a plastic component 1 in a schematic representation.

[0037] In the Fig. 1 and Fig. 2, the plastic component 1 comprises three plate-shaped partial bodies 2.1, 2.2, 2.3, which are arranged in layers one above the other.

[0038] The partial bodies 2.1, 2.2, 2.3 not only have different overall thicknesses, but they are also designed differently, with recesses 3 of varying depths, whereby the recesses 3 of adjacent partial bodies 2.1, 2.2; 2.2, 2.3 together form channels 4. The recesses 3 are designed as depressions or openings.

[0039] Due to the differently designed and differently deep recesses, the respective partial bodies 2.1, 2.2, 2.3 have very different wall thicknesses along their extension.

[0040] Thanks to the thermoplastic foam injection molding process, these geometrical features of the respective components 2.1, 2.2, and 2.3 are virtually irrelevant during their production. This process allows the respective plate-shaped components 2.1, 2.2, and 2.3 to be designed as required for their function, without having to consider specific injection molding features.

[0041] This process prevents sink marks and undesirable distortion; the parts exhibit the greatest possible precision with the smallest tolerances. This also results in particularly accurate plastic component 1.

[0042] Another advantage of the process is that it results in highly precise channel structures with surfaces that are free of sink marks and other defects typical of conventional injection molding, thus ensuring particularly low-loss transport through the channel.

[0043] In these exemplary embodiments, the partial bodies 2.1, 2.2, 2.3 are metallized with an electrically conductive coating 5. This allows the plastic component 1 to be used as a waveguide antenna, with the electromagnetic waves propagating within the channels 4.

Claims

[1] Method for producing a plastic component (1), comprising at least two plate-shaped partial bodies (2.1, 2.2, 2.3) which are arranged one above the other in layers and each have at least one recess (3) on their mutually facing sides, wherein the recesses (3) together delimit a channel (4) and wherein the partial bodies (2.1, 2.2, 2.3) are each produced in a thermoplastic foam injection molding process and are then connected to one another in layers to form the plastic component (1). [2] Method according to claim 1, characterized by that the partial bodies (2.1, 2.2, 2.3) are provided with a coating (5) following their production. [3] Method according to claim 2, characterized by that the coating (5) is electrically conductive. [4] Method according to one of claims 1 to 3, characterized by that the partial bodies (2.1, 2.2, 2.3) are metallized after their production. [5] Method according to claim 4, characterized by that the metallized partial bodies (2.1, 2.2, 2.3) are soldered together to form the plastic component (1). [6] Plastic component, produced according to one of claims 1 to 5, comprising at least two plate-shaped partial bodies (2.1, 2.2, 2.3), which are arranged in layers one above the other and each have at least one recess (3) on their mutually facing sides, wherein the recesses (3) together delimit a channel (4). [7] Use of a plastic component (1) according to claim 6 as a transport and control system for material, energy and information flows. [8] Use of a plastic component (1) according to claim 7 as a waveguide antenna.

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