METHOD FOR PRODUCING AN EMC SHIELDING HOUSING, AND EMC SHIELDING HOUSING

Abstract

In a method for producing an EMC shielding housing, an EMC active fabric in the form of a prepreg is placed in a molding tool, and is overmolded with at least one plastic component in order to form a plastic molded part or an encapsulation compound integrated into the molded part.

Claims

1. A method for producing an electromagnetic compatibility (EMC) shielding housing, which comprises the steps of: placing an EMC active fabric in a molding tool; and overmolding the EMC active fabric with at least one plastic component in the molding tool.

2. The method according to claim 1, which further comprises forming the EMC shielding housing with a plastic molded part by overmolding the EMC active fabric with the at least one plastic component to form the molded part.

3. The method according to claim 1, which further comprises forming the EMC shielding housing with a plastic molded part and an encapsulation compound integrated into the molded part to encapsulate electronics by overmolding the EMC active fabric with the at least one plastic component to form the molded part and/or the at least one plastic component to form the encapsulation compound.

4. The method according to claim 1, which further comprises placing the EMC active fabric, in a form of a prepreg, in the molding tool.

5. The method according to claim 1, wherein the at least one plastic component contains a thermoplastic for the overmolding of the EMC active fabric.

6. The method according to claim 2, which further comprises forming the molded part from a plurality of plastic components.

7. An electromagnetic compatibility (EMC) shielding housing, comprising: a plastic molded part; and an EMC active fabric integrated into said plastic molded part.

8. The EMC shielding housing according to claim 7, wherein said EMC active fabric is overmolded with at least one plastic component of said plastic molded part.

9. The EMC shielding housing according to claim 7, wherein: further comprising an encapsulation compound for encapsulating electronics, said encapsulation compound is integrated into said plastic molded part; and said EMC active fabric is overmolded with at least one further plastic component of said encapsulation compound.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0025] FIG. 1 is a diagrammatic, sectional view of an EMC shielding housing according to one exemplary embodiment of the present invention;

[0026] FIG. 2 is a sectional view to explain a production method of the EMC shielding housing according to a first embodiment variant of the invention; and

[0027] FIG. 3 is a sectional view to explain the production method of the EMC shielding housing according to a second embodiment variant of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0028] Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown a basic structure of an EMC shielding housing 10 according to one exemplary embodiment of invention.

[0029] The EMC shielding housing 10 is used for EMC active shielding of electronics 12, which are enclosed at least partially by the EMC shielding housing 10. The electronics 12 include, for example, a circuit board with electronic components of an electronic device, for example of an electric motor, drive element, control device, etc. The electronics 12 with the EMC shielding housing may, for example, be used in electronic household devices such as washing machines, hotplates, cookers, microwave ovens, dishwashers and the like.

[0030] The EMC shielding housing 10 contains a plastic molded part 14 made of one or more plastic components, which has been molded by an injection molding method. An EMC active fabric 16 is integrated in the plastic molded part 14. The integration is carried out, for example, by at least partial overmolding of the fabric 16 with at least one plastic component of the plastic molded part, as described below.

[0031] The electronics 12 may furthermore be encapsulated in an encapsulation compound 18. The encapsulation compound 18 is preferably molded from a plastic component and is preferably thermally conductive. Besides thermal dissipation and mechanical support of the electronics 12, the encapsulation compound 18 may also be used for electrical insulation of the electronics 12. The electronics 12 with the encapsulation compound 18 may optionally be integrated with the plastic molded part 14, for example by a common injection molding process, or may be inserted as a separate unit into the plastic molded part 14.

[0032] Two variants of a production method for such an EMC shielding housing will be explained in more detail below with the aid of FIGS. 2 and 3. The EMC shielding effect is in this case integrated by composite injection molding, or inline in the injection molding process, into the plastic molded part 14 of the EMC shielding housing 10.

[0033] In the embodiment variant of FIG. 2, the integration of the electronics 12 into the EMC shielding housing 10 is carried out in a single manufacturing step with a plurality of injection molding processes carried out sequentially or in parallel in a molding tool 20.

[0034] First, the electronics 12 are placed in the molding tool 20. A plastic component 28 is then injected in order to form the encapsulation compound 18. The EMC active fabric 16 in the form of a prepreg 22, i.e. a fabric (for example made of metal, plastic and/or textile fibers) impregnated with a plastic material (for example a thermoset) is then placed in the molding tool.

[0035] A first plastic component 24 for forming the plastic molded part 14 is then first injected next to the plastic component 28 for the encapsulation compound 18. The first plastic component 24 preferably consists of a thermally conductive plastic material. The plastic components 24 and 28 in this case fuse together in their transition region.

[0036] The prepreg 22 of the EMC active fabric 16 is subsequently back-molded with a second plastic component 26 for the plastic molded part 14. That is to say, the second plastic component 26 is injected between the first plastic component 24 for the molded part 14 and the prepreg 22, and in this case also penetrates through the prepreg 22. The plastic components 24 and 26 in this case fuse together. The second plastic component 26 preferably is formed of an elastomer, by the temperature effect and pressure effect of which during curing of the molded part 14 the plastic material in the prepreg 22 is also cured, and a subsequent curing process can be obviated.

[0037] In this embodiment variant, the EMC active fabric 16 is located finally in the outer region of the plastic molded part 14 of the EMC shielding housing 10.

[0038] In the embodiment variant of FIG. 3, the integration of the electronics 12 into the EMC shielding housing 10 is likewise carried out in a single manufacturing step with a plurality of injection molding processes carried out sequentially or in parallel in a molding tool 20.

[0039] First, the electronics 12 and the EMC active fabric 16 in the form of a prepreg 22, i.e. a fabric impregnated with a plastic material, are placed in the molding tool 20. In this case, the prepreg 22 encloses the electronics 12 at a particular distance therefrom. The plastic component 28 for forming the encapsulation compound 18 is then injected. The plastic component 28 is preferably electrically nonconductive, so that the electronics 12 are insulated from the EMC active fabric 16. The plastic component 28 for the encapsulation compound 18 in this case penetrates at least partially through the prepreg 22.

[0040] A first plastic component 24 for forming the plastic molded part 14 is then first injected into the molding tool 20 next to the prepreg 22 and the plastic component 28 for the encapsulation compound 18. The plastic component 28 for the encapsulation compound 18 and the first plastic component 24 for the molded part 14 each preferably consist of a thermally conductive plastic material.

[0041] A second plastic component 26 for the molded part 14 is subsequently injected next to the first plastic component 24 for the molded part 14. The second plastic component 26 preferably formed of an elastomer, by the temperature effect and pressure effect of which during curing of the molded part 14 the plastic material in the prepreg 22 is also jointly cured, and a subsequent curing process can be obviated.

[0042] In this embodiment variant, the EMC active fabric 16 is located finally between the encapsulation compound 18, encapsulating the electronics 12, and the plastic molded part 14 of the EMC shielding housing 10, the encapsulation compound 18 and the molded part 14 being integrated with one another by the injection molding process.

[0043] The invention has been explained with the aid of various exemplary embodiments with reference to FIGS. 1 to 3. The person skilled in the art will easily identify various embodiment variants of the invention which fall within the protective scope defined by the appended claims.

[0044] Other features which are considered as characteristic for the invention are set forth in the appended claims.

[0045] For instance, in the two embodiment variants of FIGS. 2 and 3, the plastic molded part 14 is respectively formed from two plastic components 24, 26. As an alternative, the molded part 14 may also be formed from just one plastic component or from more than two plastic components.

[0046] Furthermore, in the two embodiment variants of FIGS. 2 and 3, the second plastic component 26 for the molded part 14 in each case consists of an elastomer, by the temperature effect and pressure effect of which the plastic material in the prepreg 22 is also jointly cured. If other plastic materials are used for the second plastic component 26, the plastic material in the prepreg 22 may possibly need to be cured in a separate curing process.

[0047] Furthermore, the EMC shielding housing 10 encloses the electronics 12 only partially in the two embodiment variants of FIGS. 2 and 3. As an alternative, the molded part 14 of the EMC shielding housing 10 may also enclose the electronics 12 fully. Electrical terminals of the electronics are then, for example, passed through the plastic components 24-26 of the EMC shielding housing 10.

[0048] The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention: [0049] 10 EMC shielding housing [0050] 12 electronics [0051] 14 plastic molded part [0052] 16 EMC active fabric [0053] 18 encapsulation compound [0054] 20 molding tool [0055] 22 prepreg for EMC active fabric [0056] 24 first plastic component for molded part [0057] 26 second plastic component for molded part [0058] 28 plastic component for encapsulation compound