A filter housing structure

Abstract

This utility model discloses a filter housing structure, including a housing. The housing comprises a protective layer, a soft magnetic layer, and a metal base layer arranged sequentially from top to bottom. The protective layer, soft magnetic layer, and metal base layer are tightly bonded together. An ATO layer is embedded inside the soft magnetic layer, dividing the soft magnetic layer into upper and lower layers. This utility model provides a filter housing structure that employs a multi-layer shielding structure to improve the shielding performance of the housing.

Description

Technical Field

[0001] This utility model relates to the field of filter products, and in particular to a filter housing structure. Background Technology

[0002] In the field of filter product manufacturing, in order to meet the requirements of integration and electromagnetic compatibility, the core components and auxiliary electronic components of the filter are usually encapsulated in a metal housing, and the electrical signal connection with the user equipment is achieved through external terminals.

[0003] Currently, most filter housings are made of single-layer metal materials (such as aluminum alloy, galvanized steel plate, etc.). However, this traditional single-layer metal housing has significant limitations when operating at high frequencies. Due to the skin effect of high-frequency electromagnetic waves, the current mainly flows in the conductor surface layer, resulting in insufficient attenuation capability of single-layer metal for high-frequency interference. This leads to a decrease in overall shielding effectiveness, making it unable to effectively suppress the radiation and conduction of high-frequency electromagnetic interference, thus affecting the normal operation performance and signal integrity of the filter. Utility Model Content

[0004] The purpose of this invention is to provide a filter housing structure that employs a multi-layer shielding structure to improve the shielding performance of the housing.

[0005] The technical solution adopted in the housing structure of the filter disclosed in this utility model is: The device includes a housing, which comprises a protective layer, a soft magnetic layer, and a metal base layer arranged sequentially from top to bottom. The protective layer, the soft magnetic layer, and the metal base layer are tightly bonded together. An ATO layer is embedded inside the soft magnetic layer, dividing the soft magnetic layer into upper and lower layers.

[0006] As a preferred embodiment, the soft magnetic layer is made of ferrite material and is used to absorb and reflect some electromagnetic waves.

[0007] As a preferred embodiment, the ATO layer is a tin oxide thin film used for impedance matching of electromagnetic waves.

[0008] As a preferred embodiment, the metal substrate is iron-plated with nickel to reflect electromagnetic waves.

[0009] As a preferred embodiment, the protective layer is an antioxidant layer.

[0010] The beneficial effects of the filter housing structure disclosed in this utility model are: After the incident electromagnetic wave passes through the protective layer and enters the upper layer of the soft magnetic layer, this layer absorbs the electromagnetic wave for the first time and reflects some of its energy. The remaining electromagnetic wave enters the ATO layer, where impedance matching is achieved, enabling the electromagnetic wave to be transmitted without reflection. This allows the electromagnetic wave to be efficiently fed into the lower layer of the soft magnetic layer, improving the absorption bandwidth and efficiency. The remaining electromagnetic wave continues to enter the lower layer of the soft magnetic layer, where it is absorbed a second time and reflects some of its energy again. The remaining electromagnetic wave reaches the metal substrate and is reflected. The reflected electromagnetic wave passes through the soft magnetic layer and the ATO layer again and is absorbed once more. At the same time, the incident electromagnetic wave and the reflected electromagnetic wave cancel each other out, further enhancing the absorption bandwidth effect and ultimately improving the electromagnetic shielding performance of the shell. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the housing structure of a filter according to the present invention.

[0012] Figure 2 This is a cross-sectional view of the housing structure of a filter according to this utility model.

[0013] Figure 3 This utility model relates to a filter housing structure. Figure 2 (Area A) Enlarged view.

[0014] Figure 4 This is a schematic diagram of the operation of the housing structure of a filter according to this utility model. Detailed Implementation

[0015] The present invention will be further described and illustrated below with reference to specific embodiments and the accompanying drawings: Please refer to Figures 1-3 .

[0016] The present invention discloses a filter housing structure, including a housing 5, the housing 5 including an upper shell 51 and a cover plate 52, the filter core components and auxiliary electronic components are installed in the upper shell 51, and the cover plate 52 is placed on the upper shell 51 to encapsulate the filter core components and auxiliary electronic components in the upper shell 51. Both the upper shell 51 and the cover plate 52 include a protective layer 511, a soft magnetic layer 512 and a metal base layer 514 arranged sequentially from top to bottom, and the protective layer 511, the soft magnetic layer 512 and the metal base layer 514 are tightly attached to each other; an ATO layer 513 is embedded inside the soft magnetic layer 512, and the ATO layer 513 divides the soft magnetic layer 512 into upper and lower layers. Furthermore, in this embodiment, the protective layer 511 is preferably treated with anti-oxidation and has a thickness of 1μm-3μm. The protective layer 511 is located on the surface of the upper shell 51 and the cover plate 52, so that the protective layer 511 can isolate the soft magnetic layer 512 from contact with air and achieve the effect of anti-corrosion and anti-oxidation. Furthermore, in this embodiment, the soft magnetic layer 512 is preferably made of ferrite material and is a high permeability material with a thickness of 0.5-1μm. The soft magnetic layer 512 utilizes the characteristics of ferrite to absorb and reflect part of the electromagnetic waves. The absorption loss of the soft magnetic layer 512 is A1, the reflection loss is R1, and the multiple reflection loss is B1. Furthermore, in this embodiment, the ATO layer 513 is preferably a tin oxide thin film with a thickness of 100nm-300nm; both the soft magnetic layer 512 and the ATO layer 513 are located in the middle layer between the upper shell 51 and the cover plate 52. The ATO layer 513 utilizes the characteristics of the tin oxide thin film to perform impedance matching for electromagnetic waves, thereby enhancing the absorption and reflection effect of the soft magnetic layer 512 on electromagnetic waves. The matching impedance is adjusted according to the signal frequency band, with an adjustment range of 50Ω-100Ω. The absorption loss is A2, the reflection loss is R2, and the multiple reflection loss is B2. Furthermore, in this embodiment, the preferred metal base layer 514 is iron-plated nickel, with a thickness of 1-2 mm. The metal base layer 514 is located at the bottom of the upper shell 51 and the cover plate 52. The metal base layer 514 uses the characteristics of iron-plated nickel to reflect electromagnetic waves, with an absorption loss of A4, a reflection loss of R4, and a multiple reflection loss of B4.

[0017] Please refer to Figures 1-4 .

[0018] Since the protective layer 511 does not reflect or block electromagnetic waves, the incoming electromagnetic waves pass through the protective layer 511 and enter the upper layer of the soft magnetic layer 512. This layer uses the properties of ferrite to absorb and reflect part of the electromagnetic waves for the first time. The remaining electromagnetic waves pass through the upper layer of the soft magnetic layer 512 and enter the ATO layer 513. This layer uses the characteristics of the tin oxide film to perform impedance matching for the electromagnetic waves. The electromagnetic waves are transmitted without reflection on the ATO layer 513, thereby efficiently feeding the electromagnetic waves into the lower layer of the soft magnetic layer 512 to improve the absorption and reflection effect of the lower layer of the soft magnetic layer 512 on the electromagnetic waves. The remaining electromagnetic waves continue to enter the lower layer of the soft magnetic layer 512, where the ferrite material is used to absorb and reflect some of the electromagnetic waves a second time. The remaining electromagnetic waves are reflected after reaching the metal base layer 514. The reflected electromagnetic waves pass through the soft magnetic layer 512 and the ATO layer 513 again and are absorbed again. At the same time, the incident electromagnetic waves and the reflected electromagnetic waves cancel each other out, further enhancing the absorption bandwidth effect and ultimately improving the electromagnetic shielding performance of the shell 5.

[0019] The shielding effectiveness of housing 5 is measured as follows: SE=20lgA1+20lgR1+20lgB1+20lgA2+20lgR2+20lgB2+20lgA3+20lgR3+20lgB3+20lgA4+20lgR4+20lgB4; Absorption loss: A = 8.68t1 / t2 (t1 is the shield thickness, t2 is the skin depth). When the frequency is higher, the skin depth is smaller, and the value of A is larger. Reflection loss: R=(Zm+Zw)² / 4ZmZw, (Zm is the transmission impedance, Zw is the spatial impedance). The ZmZw of high permeability ferrite is larger than that of metallic materials, resulting in greater reflection loss. Multiple reflection loss: B = 1 - ((Zm-Zw) / (Zm+Zw))²10 - 0.1A², the loss of multiple reflections between layers will tend to 1; As can be seen from the above formula, when the shielding layer and ferrite reach the process thickness, the A value is relatively large, multiple reflections can be ignored, the field strength propagating to the next layer has been significantly weakened, and the final shielding effectiveness SE will reach a high level.

[0020] This invention provides a filter housing structure. After an incident electromagnetic wave passes through the protective layer and enters the upper layer of the soft magnetic layer, this layer absorbs and reflects part of the energy of the electromagnetic wave for the first time. The remaining electromagnetic wave enters the ATO layer, where impedance matching is achieved, enabling the electromagnetic wave to be transmitted without reflection. This allows the electromagnetic wave to be efficiently fed into the lower layer of the soft magnetic layer, improving the absorption bandwidth and efficiency. The remaining electromagnetic wave continues to enter the lower layer of the soft magnetic layer, where it is absorbed a second time and reflects part of the energy again. The remaining electromagnetic wave reaches the metal substrate and is reflected. The reflected electromagnetic wave passes through the soft magnetic layer and the ATO layer again and is absorbed again. At the same time, the incident electromagnetic wave and the reflected electromagnetic wave cancel each other out, further enhancing the absorption bandwidth effect and ultimately improving the electromagnetic shielding performance of the housing.

[0021] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit the scope of protection of this utility model. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the essence and scope of the technical solutions of this utility model.

Claims

1. A filter housing structure, characterized in that, The device includes a housing, which comprises a protective layer, a soft magnetic layer, and a metal base layer arranged sequentially from top to bottom. The protective layer, the soft magnetic layer, and the metal base layer are tightly bonded together. An ATO layer is embedded inside the soft magnetic layer, dividing the soft magnetic layer into upper and lower layers.

2. The housing structure of a filter as described in claim 1, characterized in that, The soft magnetic layer is made of ferrite material and is used to absorb and reflect some electromagnetic waves.

3. The housing structure of a filter as described in claim 2, characterized in that, The ATO layer is a tin oxide thin film used for impedance matching of electromagnetic waves.

4. The housing structure of a filter as described in claim 3, characterized in that, The metal base layer is made of iron plated with nickel, and is used to reflect electromagnetic waves.

5. The housing structure of a filter as described in claim 4, characterized in that, The protective layer is an antioxidant layer.

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