A hybrid filter assembly for mitigating electromagnetic interference (EMI) and sound attenuation

Abstract

The present disclosure envisages a hybrid filter assembly (100A, 100B, 100C, 100D) for mitigating electromagnetic interference (EMI) and sound attenuation. The hybrid filter assembly (100A, 100B, 100C, 100D) inludes a honeycomb structure (10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H) and the louver structure (20A, 20B, 20C). The honeycomb structure (10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H) is made from of a metallic material for electromagnetic interference (EMI) attenuation. The honeycomb structure (10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H) includes a honeycomb core, a frame for supporting the honeycomb core, and a protective screen. The louver structure (20A, 20B, 20C) integrated with the honeycomb structure (10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H). The louver structure (20A, 20B, 20C) is configured for sound attenuation and includes a sound-absorbing material consisting of at least one of foam (22), cork (24), and fire-resistant (FR) cotton fiber (26).

Description

A HYBRID FILTER ASSEMBLY FOR MITIGATING ELECTROMAGNETICINTERFERENCE (EMI) AND SOUND ATTENUATIONFIELD

[0001] The present disclosure relates to the field of filtering units for reducing electromagnetic interference (EMI) and audible noise of various equipment.

[0002] More particularly, embodiments of the present disclosure relate to a hybrid filter assembly for mitigating electromagnetic interference (EMI) and sound attenuation.BACKGROUND

[0003] The background information herein below relates to the present disclosure but is not necessarily prior art.

[0004] There is an immense need in the present market for reduction or attenuation in electromagnetic interference (EMI) and audible noise generated by power generation equipment, modern warfare / combat vehicles, combustion engines, electrical switchgear, power electronics bases equipment, etc., which require fresh air or air ventilation for their operation. Various observations reveal a great impact of electromagnetic waves and audible noise, and their resultant field of charge on human health as well as biodiversity by causing diseases such as cancer, neurological illnesses, mental disorders, etc.

[0005] To prevent such an impact on human health and the environment, currently filtering units such as filtering units made of electrically conductive material are used for mitigation of electromagnetic radiation across louvered areas. Conversely, audible noise mitigation is achieved by employing sound-absorbing material across the louvered areas. However, these conventional filtering units can be used for either for attenuating only EMI or audible noise at a time. If both the filtering units are to be used simultaneously, the system becomes bulky, adds to the weight, and is costly for installation and maintenance.

[0006] There is therefore felt a need for a hybrid filter assembly for mitigating electromagnetic interference (EMI) and sound attenuation that alleviates the aforementioned drawbacks.OBJECTS

[0007] Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:

[0008] An object of the present disclosure is to provide a hybrid filter assembly for mitigating electromagnetic interference (EMI) and sound attenuation.

[0009] Another object of the present disclosure is to provide a hybrid filter assembly that is easy to install.

[0010] Yet another object of the present disclosure is to provide a hybrid filter assembly that is compact in size.

[0011] Still another object of the present disclosure is to provide a hybrid filter assembly which can be integrated with existing equipment.

[0012] One object of the present disclosure is to provide a hybrid filter assembly which is economical.

[0013] Another object of the present disclosure is to provide a hybrid filter assembly that has relatively better efficiency.

[0014] Yet another object of the present disclosure is to provide a hybrid filter assembly that is light in weight.

[0015] Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.SUMMARY

[0016] This summary is provided to introduce concepts related to a hybrid filter assembly for mitigating electromagnetic interference (EMI) and sound attenuation. The concepts are further described below in the following detailed description. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.

[0017] The present disclosure envisages a hybrid filter assembly for mitigating electromagnetic interference (EMI) and sound attenuation. The system comprises a honeycomb structure and a louver structure. The honeycomb structure is made from a metallic material for electromagnetic interference (EMI) attenuation. The honeycomb structure includes a honeycomb core, a frame for supporting the honeycomb core, and a protective screen. The louver structure is integrated with the honeycomb structure. The louver structure is configured for sound attenuation and includes a sound-absorbing material consisting of at least one of foam, cork, and fire-resistant (FR) cotton fiber.

[0018] In an embodiment, the metallic material of the honeycomb structure is selected from the group consisting of aluminum, stainless steel, copper, or tin-plated metal.

[0019] In an embodiment, the honeycomb structure is arranged in configurations selected from plain, offset, and orthogonal alignments within the louver structure.

[0020] In an embodiment, the sound attenuation material further are arranged in a layered combination including one or more of: a first layer of foam; a second layer of cork; and a third layer of FR cotton fiber.

[0021] In an embodiment, the honeycomb structure is composed of aluminum, and the louver structure is made from sheet steel.

[0022] In an embodiment, the louver structure includes at least two louver elements arranged in a sandwich configuration with the honeycomb structure for simultaneous attenuation of electromagnetic interference and audible sound.

[0023] In an embodiment, at least two louver elements include an inside louver element and an outside louver element.

[0024] In an embodiment, the inside louver element includes louver fins angled at an angle ranging from 30 to 60 degrees. The outside louver element includes louver fins angled at an angle ranging from 120 to 150 degrees.

[0025] In an embodiment, the louver fins of the inside louver element and the outside louver element are inclined at the same angle ranging from 30 to 60 degrees.

[0026] In an embodiment, the honeycomb core is arranged in a 90-degree offset to the louver elements.

[0027] In an embodiment, the honeycomb structure includes at least two honeycomb elements arranged in a sandwich configuration with the louver structure for simultaneous attenuation of electromagnetic interference and audible sound.

[0028] In an embodiment, the louver structure includes louver fins angled at an angle ranging from 30 to 60 degrees.

[0029] In an embodiment, the honeycomb structure comprises multiple overlapping honeycomb filters, arranged to create an offset pattern to enhance EMI attenuation by increasing the absorptive surface area and inducing turbulence in the electromagnetic waves.

[0030] In an embodiment, the foam is a Polyurethane foam with open cells.

[0031] In an embodiment, the louver structure comprises sheet steel configured to provide the structural frame and the protective screen for the honeycomb core.

[0032] In an embodiment, the hybrid filter assembly is operable within a temperature range of -40°C to +55°C and a humidity range of up to 98%, ensuring effective performance across various environmental conditions, including dusty plains, deserts, and high altitudes.BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING

[0033] A hybrid filter assembly for mitigating electromagnetic interference (EMI) and sound attenuation of the present disclosure will now be described with the help of the accompanying drawing, in which:

[0034] Figure 1(a) illustrates an exploded view of a hybrid filter assembly, in accordance with an embodiment of the present disclosure;

[0035] Figure 1(b) illustrates a first embodiment of the hybrid filter assembly, in accordance with an embodiment of the present disclosure;

[0036] Figure 1(c) illustrates a second embodiment of the hybrid filter assembly, in accordance with an embodiment of the present disclosure;

[0037] Figure 1(d) illustrates a third embodiment of the hybrid filter assembly, in accordance with an embodiment of the present disclosure;

[0038] Figure 2(a) illustrates a first embodiment of a honeycomb structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0039] Figure 2(b) illustrates a second embodiment of the honeycomb structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0040] Figure 2(c) illustrates a third embodiment of the honeycomb structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0041] Figure 2(d) illustrates a fourth embodiment of the honeycomb structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0042] Figure 2(e) illustrates a fifth embodiment of the honeycomb structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0043] Figure 2(f) illustrates a sixth embodiment of the honeycomb structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0044] Figure 2(g) illustrates a seventh embodiment of the honeycomb structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0045] Figure 2(h) illustrates an eighth embodiment of the honeycomb structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0046] Figure 3(a) illustrates a first embodiment of a louver structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0047] Figure 3(b) illustrates a second embodiment of a louver structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0048] Figure 3(c) illustrates a third embodiment of a louver structure of the hybrid filter assembly of Figure 1(a) through Figure 1(d), in accordance with an embodiment of the present disclosure;

[0049] Figure 4(a) illustrates the arrangement of the honeycomb structure and the louver structure, in accordance with an embodiment of the present disclosure;

[0050] Figure 4(b) illustrates multiple overlapping honeycomb filters of honeycomb structure, in accordance with an embodiment of the present disclosure;

[0051] Figure 5(a) illustrates a graphical representation of EMI Readings without filter, in accordance with an embodiment of the present disclosure; and

[0052] Figure 5(b) illustrates a graphical representation of EMI Readings with filter, in accordance with an embodiment of the present disclosure.LIST OF REFERENCE NUMERALSDETAILED DESCRIPTION

[0053] Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.

[0054] Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.

[0055] The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggestsotherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and / or components, but do not forbid the presence or addition of one or more other features, elements, components, and / or groups thereof.

[0056] A preferred mechanism for a hybrid filter assembly 100A, 100B, 100C, 100D for mitigating electromagnetic interference (EMI) and sound attenuation of the present disclosure will now be described in detail with reference to Figure 1(a) to Figure 5(B).

[0057] As can be seen from Figures 1(a) to 1(d), the hybrid filter assembly 100A, 100B, 100C, 100D (hereinafter referred to as ‘the assembly 100A, 100B, 100C, 100D) includes a honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H and a louver structure 20A, 20B, 20C.

[0058] The honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H, shown in Figures 2(a) to 2(h), is made from a metallic material for electromagnetic interference (EMI) attenuation. The honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H includes a honeycomb core, a frame for supporting the honeycomb core, and a protective screen.

[0059] In an embodiment, the metallic material of the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H is selected from the group consisting of aluminum, stainless steel, copper, or tin-plated metal.

[0060] In an embodiment, the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H is arranged in configurations selected from plain, offset, and orthogonal alignments within the louver structure 20A, 20B, 20C.

[0061] Further, as shown in Figures 1(a), the hybrid filter assembly 100A, 100B, 100C, 100D includes the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H sandwiched between louver elements of the louver structure 20A, 20B, 20C to form the hybrid filter assembly 100A.

[0062] In another embodiment, as shown in Figure 1(b), the louver structure 20A, 20B, 20C is arranged such that one louver element of the louver structure 20A, 20B, 20C faces the second louver element of the louver structure 20A, 20B, 20C to form the hybrid filter assembly 100B. In this embodiment, an inside louver element (shown on left side of honeycomb structure) includes louver fins angled at an angle ranging from 30 to 60 degrees, while an outside louver element (shown on right side of the honeycomb structure) includes louver fins angled at an angle ranging from 120 to 150 degrees.

[0063] In yet another embodiment, as shown in Figure 1(c), the louver structure 20A, 20B, 20C is arranged such that both the louver elements of the louver structure 20 A, 20B,20C are aligned in the same direction to form the unit to form the hybrid filter assembly 100C. In this embodiment, the louver fins of the inside louver element and the outside louver element are inclined at the same angle ranging from 30 to 60 degrees.

[0064] In yet another embodiment, as shown in Figure 1(d), a louver element of louver structure 20A, 20B, 20C is sandwiched between honeycomb elements of the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H to form the hybrid filter assembly 100D. In this embodiment, the louver structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H includes louver fins angled at an angle ranging from 30 to 60 degrees.TABLE 1

[0065] From the above Table 1, it is inferred that all the embodiments of the hybrid filter assembly 100A, 100B, 100C, 100D provide efficient attenuation against electromagnetic radiation mitigation, sound mitigation, and ventilation.

[0066] Referring to Figure 2(a) to 2(h), the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H has a honeycomb configuration. The honeycomb structure 10B may have square, hexagonal, heptagonal, octagonal or any other configuration. Both the honeycomb and square, hexagonal, heptagonal, octagonal or any other configuration of the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H include a plurality of septa in each lumen of the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H. The septa help in attenuating electromagnetic radiations by increasing the absorption of electromagnetic radiation and creating turbulence in the flow of electromagnetic waves.

[0067] In an embodiment, the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H is arranged in configurations selected from plain, offset, and orthogonal alignments within said louver structure 20A, 20B, 20C.

[0068] Referring to Figure 3(a) to Figure 3(c), the louver structure 20A, 20B, 20C is integrated with the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H. Thelouver structure 20A, 20B, 20C is configured for sound attenuation and includes a soundabsorbing material consisting of at least one of foam 22, cork 24, and fire-resistant (FR) cotton fiber 26. The foam 22 is a Polyurethane foam with open cells. The louver structure 20A, 20B, 20C comprises sheet steel configured to provide the structural frame and the protective screen for the honeycomb core.

[0069] In an embodiment, the sound attenuation material further is arranged in a layered combination including one or more of a first layer of foam 22, a second layer of cork 24, and a third layer of FR cotton fiber 26.

[0070] In an embodiment, the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H are composed of aluminum, and the louver structure 20A, 20B, 20C is made from sheet steel.

[0071] In an exemplary embodiment, as shown in Figures 3(a), 3(b), and 3(c), the materials can be sandwiched in different combinations to perform the sound attenuation is shown in Table 2.

[0072] Table 2 studies the effect of material used for preparing the louver structure 20A, 20B, 20C 20A, 20B, 20C with respect to different frequencies of sound.

[0073] In an embodiment, the hybrid filter assembly 100A, 100B, 100C, 100D can be employed for operating temperatures varying from -40°C to +55°C, storage temperatures varying from -50°C to +70°C, altitude ranging up to 5000 meters from the MSL, and relative humidity ranging up to 98%.

[0074] In an embodiment, the hybrid filter assembly 100A, 100B, 100C, 100D can be used in applications in different locations selected from dusty, plains, deserts, mountains and high altitude regions.

[0075] In an embodiment, the hybrid filter assembly 100A, 100B, 100C, 100D can be used in generation equipments, modern warfare / combat vehicles, combustion engines, electrical switchgear, power electronics bases equipment among others.

[0076] Referring to Figure 4(a), the louver structure 20A, 20B, 20C includes at least two louver elements arranged in a sandwich configuration with the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H for simultaneous attenuation of electromagnetic interference and audible sound. The at least two louver elements 20A, 20B, 20C include an inside louver element 28 and an outside louver element 30. The inside louver element 28 includes louver fins angled at an angle ranging from 30 to 60 degrees. The outside louver element 30 includes louver fins angled at an angle ranging from 120 to 150 degrees. The honeycomb core is arranged in a 90-degree offset to the louver elements. The honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H comprises multiple overlapping honeycomb filters, arranged to create an offset pattern to enhance EMI attenuation by increasing the absorptive surface area and inducing turbulence in the electromagnetic waves. Further, as can be seen in Figure 4(a), the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H includes multiple overlapping honeycomb filters 32, arranged to create an offset pattern to enhance EMI attenuation by increasing the absorptive surface area and inducing turbulence in the electromagnetic wavesat.

[0077] Referring to Figure 4(b), the honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H includes least two honeycomb elements 34a, 34b arranged in a sandwich configuration with the louver structure 20A, 20B, 20C for simultaneous attenuation of electromagnetic interference and audible sound.

[0078] In an embodiment, the hybrid filter assembly 100A, 100B, 100C, 100D is operable within a temperature range of -40°C to +55°C and a humidity range of up to 98%, ensuring effective performance across various environmental conditions, including dusty plains, deserts, and high altitudes.

[0079] In an embodiment, the hybrid filter assembly 100A, 100B, 100C, 100D allows ventilation while maintaining effective attenuation of electromagnetic radiation and sound without significant airflow restriction. The combination of EMI and sound attenuation layers provides a compact and lightweight structure that can be easily integrated into existing power generation equipment, warfare vehicles, and electrical switchgear systems. The honeycomb structure 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H comprises an array of cells arranged to enhance electromagnetic wave dissipation by increasing absorptive surface area and creating turbulence in the electromagnetic field.In an embodiment, the louver structure 20A, 20B, 20C is configured in an offset arrangement at an angle of approximately 90 degrees to further enhance sound attenuation and create turbulence in electromagnetic wave flow for improved EMI attenuation.

[0080] Figure 5(a) illustrates a graphical representation of EMI Readings without filter, in accordance with an embodiment of the present disclosure; and

[0081] Figure 5(b) illustrates a graphical representation of EMI Readings with filter, in accordance with an embodiment of the present disclosure.

[0082] In an embodiment, the EMI attenuation performance reduces electromagnetic radiation by at least 5 to 6 dBpV / m for frequencies above 110 MHz under operational conditions.

[0083] Audible sound level without filter is 86 DbA.Reduction in sound level by 7 to 10 Db

[0084] The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.TECHNICAL ADVANCEMENTS

[0085] The present disclosure described herein above has several technical advantages including, but not limited to, the hybrid filter assembly for mitigating electromagnetic interference (EMI) and sound attenuation that:• efficiently attenuates electromagnetic interference (EMI);• efficiently attenuates sound;• is compact in size;• is lightweight;• is economical;• is easy to install; and• is easy to be integrated with existing equipments.

[0086] The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

[0087] The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

[0088] The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.

[0089] Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

[0090] The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher / lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.

[0091] While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

Claims

CLAIMS:

1. A hybrid filter assembly (100A, 100B, 100C, 100D) for mitigating electromagnetic interference (EMI) and sound attenuation, comprising: a honeycomb structure (10A, 10B, IOC, 10D, 10E, 10F, 10G, 10H) made from of a metallic material for electromagnetic interference (EMI) attenuation, said honeycomb structure (10A, 10B, IOC, 10D, 10E, 10F, 10G, 10H) including: a honeycomb core; a frame for supporting the honeycomb core; and a protective screen; and a louver structure (20A, 20B, 20C) integrated with said honeycomb structure (10A, 10B, IOC, 10D, 10E, 10F, 10G, 10H), said louver structure (20A, 20B, 20C) being configured for sound attenuation and including a sound-absorbing material consisting of at least one of foam (22), cork (24), and fire-resistant (FR) cotton fiber (26).

2. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 1, wherein the metallic material of the honeycomb structure (10A, 10B, IOC, 10D, 10E, 10F, 10G, 10H) is selected from the group consisting of aluminum, stainless steel, copper, or tin-plated metal.

3. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 1, wherein said honeycomb structure (10A, 10B, IOC, 10D, 10E, 10F, 10G, 10H) is arranged in configurations selected from plain, offset, and orthogonal alignments within said louver structure (20 A, 20B, 20C).

4. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 1, wherein the sound attenuation material further are arranged in a layered combination including one or more of: a first layer of foam (22); a second layer of cork (24); and a third layer of FR cotton fiber (26).

5. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 1, wherein the honeycomb structure (10A, 10B, IOC, 10D, 10E, 10F, 10G, 10H) is composed of aluminum, and the louver structure (20A, 20B, 20C) is made from sheet steel.

6. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 1, wherein the louver structure (20A, 20B, 20C) includes at least two louver elements arranged in a sandwich configuration with said honeycomb structure (10A, 10B, IOC, 10D, 10E, 10F, 10G, 10H) for simultaneous attenuation of electromagnetic interference and audible sound.

7. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 6, wherein the at least two louver elements (20 A, 20B, 20C) include an inside louver element (28) and an outside louver element (30).

8. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 6, wherein the inside louver element (28) includes louver fins angled at an angle ranging from 30 to 60 degrees, and wherein the outside louver element (30) includes louver fins angled at an angle ranging from 120 to 150 degrees.

9. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 6, wherein louver fins of the inside louver element (28) and the outside louver element (30) are inclined at the same angle ranging from 30 to 60 degrees.

10. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 6, wherein the honeycomb core is arranged in a 90-degree offset to the louver elements.

11. The hybrid filter assembly (100) as claimed in claim 1, wherein the honeycomb structure (10A, 10B, IOC, 10D, 10E, 10F, 10G, 10H) includes at least two honeycomb elements (34a, 34b) arranged in a sandwich configuration with said louver structure (20A, 20B, 20C) for simultaneous attenuation of electromagnetic interference and audible sound.

12. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 11, wherein said louver structure (20A, 20B, 20C) includes louver fins angled at an angle ranging from 30 to 60 degrees.

13. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 1, wherein the honeycomb structure (10A, 10B, IOC, 10D, 10E, 10F, 10G, 10H) comprises multiple overlapping honeycomb filters (32), arranged to create an offset pattern to enhance EMI attenuation by increasing the absorptive surface area and inducing turbulence in the electromagnetic waves.

14. The hybrid filter assembly (100A, 1OOB, 1OOC, 1OOD) as claimed in claim 1, wherein the foam (22) is a Polyurethane foam with open cells.

15. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 1, wherein the louver structure (20A, 20B, 20C) comprises sheet steel configured to provide the structural frame and the protective screen for the honeycomb core.

16. The hybrid filter assembly (100A, 100B, 100C, 100D) as claimed in claim 1, wherein the hybrid filter assembly (100A, 100B, 100C, 100D) is operable within a temperature range of -40°C to +55 °C and a humidity range of up to 98%, ensuring effective performance across various environmental conditions, including dusty plains, deserts, and high altitudes.

Images