An electromechanically controlled machine case

Abstract

The utility model discloses a kind of electromechanical control machine cases, including metal frame and carbon fiber composite cover plate, the carbon fiber composite cover plate contains metal screen shielding layer, the end surface of carbon fiber composite cover plate towards metal frame is equipped with annular sealing strip of protruding carbon fiber composite cover plate surface, the annular sealing strip is integrally formed with carbon fiber composite cover plate, annular sealing strip includes the conductive contact surface formed by the metal screen shielding layer extends outward and is naked;The metal frame is equipped with the annular sealing groove matched with annular sealing strip, the metal frame is equipped with the annular sealing groove matched with annular sealing strip, the outside wall of the annular sealing strip and the inside wall of annular sealing groove are closely combined to form structural seal, the conductive contact surface and the inner wall of annular sealing groove contact to form conductive connection.The utility model has the advantages that: avoid the problem that traditional independent sealing element is prone to aging, compression is not tight, leading to the problem of shielding effectiveness decline, improve the stability and reliability of machine case structure.

Description

Technical Field

[0001] This utility model relates to the field of electromagnetic shielding technology, specifically to an electromechanical control chassis. Background Technology

[0002] With the widespread application of electronic equipment, electromagnetic interference (EMI) has become a critical issue affecting equipment performance and safety. To effectively suppress EMI, electromagnetic shielding enclosures are widely used in various electronic devices. Traditional electromagnetic shielding enclosures are mostly made of metal materials (such as aluminum alloys and steel plates), which, while possessing good conductivity and shielding effectiveness, also suffer from problems such as heavy weight, susceptibility to corrosion, and high processing costs.

[0003] In recent years, carbon fiber composite materials have been increasingly introduced into the field of electromagnetic shielding due to their excellent properties such as lightweight, high strength, and corrosion resistance. For example, Chinese Patent Publication No. CN111465304A discloses a "Carbon Fiber Composite Material Shielding Chassis with Integrated Structure," comprising a chassis, cover plate, connectors, and conductive sealing strips. Both the chassis and cover plate utilize a four-layer composite carbon fiber composite material structure (including a metal shielding mesh, nickel-plated carbon fiber, and carbon fiber layers on both sides). U-shaped grooves are provided at corresponding positions on the inner flange of the chassis and the cover plate, achieving electromagnetic sealing through contact between the conductive sealing strip and the metal shielding mesh. While this solution combines the lightweight advantages of carbon fiber composite materials, it still has the following shortcomings:

[0004] The sealing structure is complex: the conductive sealing strip needs to be placed independently in the U-shaped groove, which requires high assembly precision, and the sealing strip needs to be precisely fitted with the metal shielding mesh, otherwise the electromagnetic seal may fail.

[0005] Limited reliability: The fit between the U-groove and the conductive sealing strip depends on the assembly precision. After long-term use, poor contact may occur due to vibration or deformation, affecting the shielding effectiveness.

[0006] The connection method is cumbersome: the cover plate is fixed to the box with bolts, which requires multiple bolt holes to be made on the cover plate and the box and bolts and nuts to be installed. The operation is complicated and inefficient.

[0007] Therefore, there is an urgent need for a new type of electromagnetic shielding enclosure that can retain the lightweight advantages of carbon fiber composite materials while simplifying the connection structure, improving assembly efficiency and electromagnetic sealing reliability. Utility Model Content

[0008] The purpose of this utility model is to provide an electromechanical control chassis that can effectively solve the problems of complex sealing structure and limited reliability of shielded chassis.

[0009] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution:

[0010] An electromechanical control enclosure includes a metal frame and a carbon fiber composite cover plate. The carbon fiber composite cover plate includes a metal mesh shielding layer. An annular sealing strip protrudes from the surface of the carbon fiber composite cover plate on the end face of the carbon fiber composite cover plate facing the metal frame. The annular sealing strip is integrally formed with the carbon fiber composite cover plate and includes a conductive contact surface formed by extending outward from and exposing the metal mesh shielding layer.

[0011] The metal frame is provided with an annular sealing groove that matches the annular sealing strip. The outer wall of the annular sealing strip is tightly fitted with the inner wall of the annular sealing groove to form a structural seal. The conductive contact surface contacts the inner wall of the annular sealing groove to form a conductive connection.

[0012] In the aforementioned electromechanical control chassis, permanent magnets are embedded in the metal frame and carbon fiber composite cover plate and magnetically connected to the metal frame.

[0013] In the aforementioned electromechanical control chassis, the annular sealing strip and the annular sealing groove are bonded and fixed by applying conductive adhesive, and after curing, a seamless conductive connection is formed.

[0014] In the aforementioned electromechanical control chassis, the conductive adhesive is silver paste conductive adhesive.

[0015] In the aforementioned electromechanical control enclosure, the carbon fiber composite cover plate includes a first carbon fiber layer, a metal mesh shielding layer, a metal-plated carbon fiber layer, and a second carbon fiber layer stacked sequentially, wherein the metal mesh shielding layer extends through the first carbon fiber layer and is exposed to form a conductive contact surface.

[0016] In the aforementioned electromechanical control chassis, the thickness of the first carbon fiber layer and the second carbon fiber layer is 0.56 mm, the thickness of the metal-plated carbon fiber layer is 0.8 mm, and the thickness of the metal mesh shielding layer is 0.08 mm.

[0017] In the aforementioned electromechanical control chassis, a ferrite thin film layer is further provided between the metal mesh shielding layer and the metal-plated carbon fiber layer.

[0018] In the aforementioned electromechanical control chassis, the metal-plated carbon fiber layer is a nickel-plated carbon fiber layer or a silver-plated carbon fiber layer.

[0019] In the aforementioned electromechanical control chassis, the outer surface of the carbon fiber composite cover plate is a flat, closed structure without heat dissipation grooves.

[0020] In the aforementioned electromechanical control enclosure, the metal mesh shielding layer is one of copper wire mesh, nickel-plated copper mesh, stainless steel wire mesh, or aluminum-magnesium alloy wire mesh.

[0021] Compared with the prior art, the advantages of this utility model are:

[0022] The metal mesh shielding layer in the carbon fiber composite cover plate extends to form a conductive contact surface. After being pressed together with the annular sealing groove of the metal frame, it forms a continuous conductive sealing structure, effectively blocking electromagnetic wave leakage and improving electromagnetic shielding performance. This meets the needs of aerospace, high-end military and civilian equipment, and other fields with high electromagnetic protection requirements. The annular sealing strip is integrally formed with the carbon fiber composite cover plate, eliminating the need for an additional independent conductive sealing strip. Furthermore, it transforms the traditional solution's dual-interface conductivity—where the sealing strip, frame, and metal mesh shielding layer all need to make conductive contact—into a single-interface conductivity between the conductive contact surface and the inner wall of the annular sealing groove. This significantly reduces the probability of conductive failure and improves the stability and reliability of the chassis structure.

[0023] The one-piece molded annular sealing strip eliminates the need for complex processes such as precision machining of U-shaped grooves, avoiding weakening of structural strength due to damage to fiber continuity during processing, simplifying the production process while ensuring the structural strength of the chassis. The use of carbon fiber composite cover plates combines lightweight and high strength, significantly reducing weight compared to traditional metal shielded chassis, meeting the trend of lightweight equipment development, and is especially suitable for applications with strict weight requirements.

[0024] Furthermore, permanent magnets are embedded in the metal frame and carbon fiber composite cover plate, magnetically connecting them to the metal frame. This eliminates the need for traditional bolt connections, avoiding high-frequency electromagnetic wave leakage caused by bolt hole gaps, and further improving electromagnetic shielding integrity. It is particularly suitable for equipment protection in high-frequency electromagnetic environments. The magnetic pressing connection allows for quick installation and disassembly without additional tools, significantly improving assembly efficiency and reducing maintenance costs. It is suitable for scenarios requiring frequent inspection or cover plate replacement.

[0025] Furthermore, the annular sealing strip and the annular sealing groove are bonded and fixed together by applying conductive adhesive, forming a seamless conductive connection after curing. The cured conductive adhesive fills the microscopic gaps between the sealing strip and the sealing groove, forming a continuous conductive path. This compensates for potential insufficient contact issues at the exposed contact surface of the metal mesh shielding layer, further reducing the risk of electromagnetic leakage and improving the electromagnetic shielding effectiveness in the high-frequency band. The adhesive effect of the conductive adhesive enhances the connection strength between the sealing strip and the sealing groove, preventing displacement or loosening of the sealing strip due to vibration, temperature differences, or other factors. This forms a dual-sealing structure that combines conductivity and mechanical fixation, effectively blocking external environmental interference such as dust and moisture.

[0026] Furthermore, the conductive adhesive is a silver paste conductive adhesive. Silver paste conductive adhesive uses silver particles as the main conductive filler, exhibiting extremely high conductivity. After curing, it forms a conductive path with low contact resistance, effectively reducing impedance along the electromagnetic shielding path, improving the shielding effectiveness of high-frequency electromagnetic waves, and reducing signal leakage. Silver particles easily form a continuous conductive network within the adhesive layer, maintaining good conductive continuity even under slight vibration or deformation, thus avoiding fluctuations in shielding performance due to poor contact.

[0027] Furthermore, the carbon fiber composite cover plate includes a first carbon fiber layer, a metal mesh shielding layer, a metal-plated carbon fiber layer, and a second carbon fiber layer stacked sequentially. The metal mesh shielding layer extends through the first carbon fiber layer and forms a conductive contact surface. This carbon fiber composite cover plate structure forms a composite system of "mechanical support + conductive shielding + reinforced shielding." The metal mesh shielding layer blocks electromagnetic waves through its mesh structure, while the metal-plated carbon fiber layer utilizes the conductivity of the metal plating to form a continuous shielding layer. The combination of these two elements can cover electromagnetic interference in different frequency bands, achieving broadband electromagnetic shielding. The metal mesh shielding layer extends through the first carbon fiber layer and forms a conductive contact surface, ensuring that the shielding layer at the sealing strip is directly electrically connected to the metal frame, avoiding electromagnetic leakage caused by interruptions in the shielding layer in traditional layered structures, and improving the overall shielding integrity.

[0028] Furthermore, the thickness of the first and second carbon fiber layers is 0.56 mm, the thickness of the metal-plated carbon fiber layer is 0.8 mm, and the thickness of the metal mesh shielding layer is 0.08 mm. The 0.08 mm thickness of the metal mesh shielding layer balances conductivity and flexibility: too thin a layer can lead to mesh deformation and reduced shielding effectiveness, while too thick a layer would increase the weight of the cover plate and reduce the bonding strength of the carbon fiber layers. The 0.8 mm thickness of the metal-plated carbon fiber layer compensates for the insufficient shielding of low-frequency electromagnetic waves by the metal mesh; the combination of the two achieves a broadband shielding effectiveness of ≥80 dB for 100 kHz to 10 GHz.

[0029] Furthermore, a ferrite thin film layer is provided between the metal mesh shielding layer and the metal-plated carbon fiber layer. For low-frequency interference sources such as power supply noise and motor electromagnetic radiation, the magnetic permeability (μ≥1000) of the ferrite thin film layer causes electromagnetic waves to generate hysteresis loss within the layer, converting it into heat energy dissipation. This prevents leakage caused by low-frequency electromagnetic waves penetrating the metal mesh or bypassing the metal plating layer, making it particularly suitable for scenarios sensitive to low-frequency interference, such as industrial control and medical equipment.

[0030] Furthermore, the metal-plated carbon fiber layer is either a nickel-plated carbon fiber layer or a silver-plated carbon fiber layer. Both have significant advantages in terms of conductivity, environmental adaptability, and process feasibility, and can be precisely adapted to different application scenarios.

[0031] Furthermore, the outer surface of the carbon fiber composite cover plate is a flat, closed structure without heat dissipation grooves. The groove-free design avoids cutting and damaging the carbon fiber layers, maintains the integrity and continuity of the fiber layup (fiber orientation consistency ≥95%), improves the bending strength of the cover plate, significantly enhances its impact resistance, and can withstand greater external pressure without deformation, making it suitable for harsh mechanical environments such as aerospace.

[0032] Furthermore, the metal mesh shielding layer is one of copper wire mesh, nickel-plated copper mesh, stainless steel wire mesh, or aluminum-magnesium alloy wire mesh. Different metal mesh shielding layers have different shielding performance and manufacturing costs, allowing for the selection of a suitable metal mesh shielding layer to meet different application requirements and achieve the intended design effect. Attached Figure Description

[0033] Figure 1 This is a perspective view of an electromechanical control chassis according to the present invention;

[0034] Figure 2 A perspective view of the metal frame in this utility model after a carbon fiber composite cover plate has been assembled on part of the side wall.

[0035] Figure 3 This is a schematic diagram of the carbon fiber composite cover plate in this utility model;

[0036] Figure 4 Partial cross-sectional view of the assembly of the metal frame and carbon fiber composite cover plate in this utility model. Figure 1 ;

[0037] Figure 5 Partial cross-sectional view of the assembly of the metal frame and carbon fiber composite cover plate in this utility model. Figure 2 .

[0038] The attached figures are labeled as follows:

[0039] Metal frame 10, annular sealing groove 11;

[0040] Carbon fiber composite cover plate 20, first carbon fiber layer 21, metal mesh shielding layer 22, metal-plated carbon fiber layer 23, second carbon fiber layer 24, and annular sealing strip 25;

[0041] Permanent magnet 30. Detailed Implementation

[0042] An electromechanical control chassis includes a metal frame 10 and a carbon fiber composite cover plate 20. The carbon fiber composite cover plate 20 includes a metal mesh shielding layer 22. The end face of the carbon fiber composite cover plate 20 facing the metal frame 10 is provided with an annular sealing strip 25 protruding from the surface of the carbon fiber composite cover plate 20. The annular sealing strip 25 is integrally formed with the carbon fiber composite cover plate 20. The annular sealing strip 25 includes a conductive contact surface formed by the metal mesh shielding layer 22 extending outward and exposed.

[0043] The metal frame 10 is provided with an annular sealing groove 11 that matches the annular sealing strip 25. The outer wall of the annular sealing strip and the inner wall of the annular sealing groove are tightly fitted to form a structural seal. The conductive contact surface contacts the inner wall of the annular sealing groove 11 to form a conductive connection.

[0044] The metal mesh shielding layer 22 in the carbon fiber composite cover plate 20 extends to form a conductive contact surface. After being pressed with the annular sealing groove 11 of the metal frame 10, it forms a continuous conductive sealing structure, effectively blocking electromagnetic wave leakage and improving electromagnetic shielding performance. This meets the needs of fields with high electromagnetic protection requirements, such as aerospace and high-end military and civilian equipment. The annular sealing strip 25 is integrally formed with the carbon fiber composite cover plate 20, eliminating the need for an additional independent conductive sealing strip. Furthermore, it transforms the traditional solution of dual-interface conductivity, where the sealing strip, frame, and metal mesh shielding layer all need to make conductive contact, into a single-interface conductivity between the conductive contact surface and the inner wall of the annular sealing groove. This significantly reduces the probability of conductive failure and improves the stability and reliability of the chassis structure.

[0045] The one-piece molded annular sealing strip 25 eliminates the need for complex processes such as precision machining of U-shaped grooves, avoiding weakening of structural strength due to damage to fiber continuity during processing, simplifying the production process while ensuring the structural strength of the chassis. The carbon fiber composite cover plate 20 combines lightweight and high strength, significantly reducing weight compared to traditional metal shielded chassis, meeting the trend of lightweight equipment development, and is especially suitable for applications with strict weight requirements.

[0046] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0047] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0048] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0049] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0050] See Figures 1 to 5 This invention relates to an embodiment of an electromechanical control chassis. The chassis includes a metal frame 10 and a carbon fiber composite cover plate 20. The metal frame 10 primarily provides support, while the carbon fiber composite cover plate 20 is fixed to the outer periphery of the metal frame 10, serving as electromagnetic shielding. In this embodiment, the metal frame 10 has a rectangular frame structure; however, frames of different shapes can be manufactured according to actual design needs.

[0051] The carbon fiber composite cover plate 20 includes a metal mesh shielding layer 22. The metal mesh shielding layer 22 blocks electromagnetic waves through its mesh structure. Generally, the metal mesh shielding layer 22 is not directly exposed but is encased inside the carbon fiber composite cover plate 20. The end face of the carbon fiber composite cover plate 20 facing the metal frame 10 has an annular sealing strip 25 protruding from the surface of the carbon fiber composite cover plate 20. The annular sealing strip 25 is generally arranged along the outer periphery of the carbon fiber composite cover plate 20 to form a large enough area. The annular sealing strip 25 is integrally formed with the carbon fiber composite cover plate 20, thus eliminating the need for a separate conductive sealing strip. This avoids the traditional method of separately slotting and setting a sealing strip on the carbon fiber composite cover plate 20, saving the complex process of slotting the carbon fiber composite cover plate 20, and also avoids damaging the continuity of the carbon fiber, ensuring the overall strength of the carbon fiber composite cover plate 20. The annular sealing strip 25 can be formed by laminating and extruding the metal mesh shielding layer 22 protruding from the carbon fiber composite cover plate 20; or the carbon fiber protrusions on the surface of the carbon fiber composite cover plate 20 can form the main body of the annular sealing strip 25, while the metal mesh shielding layer 22 extends through the annular sealing strip 25 and covers its surface to form a conductive contact surface.

[0052] The metal frame 10 is provided with an annular sealing groove 11 that matches the annular sealing strip 25. The annular sealing strip 25 includes a conductive contact surface formed by the outward extension and exposure of the metal mesh shielding layer 22. The outer wall of the annular sealing strip is tightly fitted with the inner wall of the annular sealing groove to form a structural seal, and the conductive contact surface contacts the inner wall of the annular sealing groove 11 to form a conductive connection. The metal mesh shielding layer 22 in the carbon fiber composite cover plate 20 extends to form a conductive contact surface. After being pressed with the annular sealing groove 11 of the metal frame 10, it can form a continuous conductive sealing structure, effectively blocking electromagnetic wave leakage and improving electromagnetic shielding effectiveness. This can meet the needs of fields with high electromagnetic protection requirements, such as aerospace and high-end military and civilian equipment. The conductive contact surface of the annular sealing strip 25 is directly formed by the exposed extension of the metal mesh shielding layer 22. During pressing, it automatically fits with the inner wall of the sealing groove, avoiding poor contact due to assembly errors.

[0053] Furthermore, in this embodiment, the carbon fiber composite cover plate 20 and the metal frame 10 are no longer fixed with bolts as in the past. Traditional bolt fixing methods can lead to high-frequency electromagnetic wave leakage through the bolt hole gaps. To address this issue, this embodiment can directly press the annular sealing strip 25 into the annular sealing groove 11, ensuring a secure connection. Alternatively, auxiliary connection methods can be used to firmly connect the carbon fiber composite cover plate 20 and the metal frame 10, including but not limited to the following:

[0054] I. For example Figure 4 As shown, conductive adhesive is applied and bonded between the annular sealing strip 25 and the annular sealing groove 11, forming a seamless conductive connection after curing. The cured conductive adhesive fills the microscopic gaps between the annular sealing strip 25 and the annular sealing groove 11, forming a continuous conductive path. This compensates for any potential insufficient contact between the conductive contact surface and the inner wall of the annular sealing strip, further reducing the risk of electromagnetic leakage and improving the high-frequency electromagnetic shielding effectiveness. Furthermore, the adhesive effect of the conductive adhesive enhances the connection strength between the annular sealing strip 25 and the annular sealing groove 11, preventing displacement or loosening of the annular sealing strip 25 due to vibration, temperature differences, or other factors. This creates a dual-seal structure that combines conductivity and mechanical fixation, effectively blocking external environmental interference such as dust and moisture.

[0055] Conductive adhesives can be made using silver paste, which uses silver particles as the main conductive filler. It has extremely high conductivity and, after curing, forms a conductive path with low contact resistance, effectively reducing impedance along the electromagnetic shielding path, improving the shielding effectiveness of high-frequency electromagnetic waves, and reducing signal leakage. Silver particles easily form a continuous conductive network in the adhesive layer, maintaining good conductive continuity even under slight vibration or deformation, avoiding fluctuations in shielding performance due to poor contact. Silver paste exhibits good adhesion to the metal mesh shielding layer 22 (such as copper, nickel, stainless steel, etc.) and carbon fiber composite material surfaces, and can be cured at room temperature or low temperature. It is compatible with the integrated molding process of the carbon fiber composite cover plate 20, requiring no additional high-temperature treatment and simplifying the production process. Besides silver paste, gold-based, carbon-based, copper-based, and nickel-based conductive adhesives can also be used depending on the specific application scenario and budget.

[0056] II. Figure 5 As shown, the metal frame 10 and the carbon fiber composite cover plate 20 are magnetically connected by embedding a permanent magnet 30. For example, a permanent magnet 30 is embedded in the carbon fiber composite cover plate 20 and magnetically presses against the metal frame 10 of the magnetic material. The uniform magnetic force generated by the permanent magnet 30 can form a stable and uniform pressing force between the annular sealing strip 25 and the annular sealing groove 11, ensuring full contact of the conductive contact surfaces, enhancing sealing reliability, and avoiding a decrease in shielding effectiveness due to localized insufficient pressing. The magnetic connection method has relatively low requirements for the processing precision of the metal frame 10 and the carbon fiber composite cover plate 20, and can be compatible with components of different sizes and specifications. At the same time, it reduces the risk of structural deformation caused by stress concentration in mechanical connections and improves the overall structural stability of the chassis. Compared with the potential problems of loosening and corrosion in bolted connections, magnetic connections have no wear on moving parts and can maintain stable connection force and sealing effect after long-term use, reducing maintenance needs and extending the service life of the chassis.

[0057] Based on the above embodiments, the carbon fiber composite cover plate 20 in this embodiment includes a first carbon fiber layer 21, a metal mesh shielding layer 22, a metal-plated carbon fiber layer 23, and a second carbon fiber layer 24 stacked sequentially. The metal mesh shielding layer 22 extends through the first carbon fiber layer 21 and forms a conductive contact surface. The stacked design of the first carbon fiber layer 21, the metal mesh shielding layer 22, the metal-plated carbon fiber layer 23, and the second carbon fiber layer 24 forms a composite system of "mechanical support + conductive shielding + enhanced shielding". The metal mesh shielding layer 22 blocks electromagnetic waves through its mesh structure, and the metal-plated carbon fiber layer 23 utilizes the conductivity of the metal plating to form a continuous shielding layer. The combination of the two can cover electromagnetic interference of different frequency bands (e.g., the metal mesh is effective for high-frequency bands, and the metal plating layer supplements low-frequency bands), achieving broadband electromagnetic shielding. The metal mesh shielding layer 22 extends through the first carbon fiber layer 21 and forms a conductive contact surface, ensuring that the shielding layer at the sealing strip is directly electrically connected to the metal frame 10, avoiding electromagnetic leakage caused by the interruption of the shielding layer in the traditional layered structure, and improving the overall shielding integrity.

[0058] Furthermore, the thickness of the first carbon fiber layer 21 and the second carbon fiber layer 24 is 0.56 mm, the thickness of the metal-plated carbon fiber layer 23 is 0.8 mm, and the thickness of the metal mesh shielding layer 22 is 0.08 mm.

[0059] The 220.08 mm thickness of the metal mesh shielding layer strikes a balance between conductivity and flexibility: too thin a layer can lead to mesh deformation and reduced shielding effectiveness, while too thick a layer increases the weight of the cover plate and reduces the bonding strength of the carbon fiber layer. At this thickness, the sheet resistivity of the metal mesh (such as copper wire mesh) can be controlled below 0.1 Ω, effectively reflecting high-frequency electromagnetic waves (>1 GHz), while minimizing diffraction loss of electromagnetic waves due to the mesh structure. If the metal mesh is too thick, it increases the difficulty of laying up the carbon fiber layer, resulting in a decrease in the flatness of the cover plate surface; if the metal mesh is too thin, it is easily deformed by the carbon fiber during the pressing process, disrupting the continuity of the conductive contact surface.

[0060] A 230.8 mm thick metal-plated carbon fiber layer forms a continuous conductive layer: sufficient metal plating thickness ensures the continuity of the internal conductive path, compensating for the insufficient shielding of low-frequency electromagnetic waves (<1 GHz) by the metal mesh. The combination of the two achieves a broadband shielding effectiveness of ≥80 dB for 100 kHz to 10 GHz. The 230.8 mm thickness of the metal-plated carbon fiber layer ensures that the carbon fiber bundle is uniformly coated (e.g., a nickel plating layer thickness ≥5 μm), avoiding plating breakage and conductivity degradation due to excessive thinness, or decreased fiber flexibility and interlaminar shear strength due to excessive thickness.

[0061] The thickness of the first carbon fiber layer 21 and the second carbon fiber layer 24 is 0.56 mm each, ensuring that the overall bending strength of the cover plate is ≥500 MPa (the tensile strength of the carbon fiber layers is dominant), and meeting the requirement that the chassis panel can withstand 100 N / m.2 The requirement is to prevent deformation under pressure, while also avoiding excessive weight due to excessive thickness.

[0062] Furthermore, a ferrite thin film layer can be provided between the metal mesh shielding layer 22 and the metal-plated carbon fiber layer 23. The ferrite thin film layer absorbs low-frequency electromagnetic waves (e.g., 100kHz to 10MHz) using magnetic loss characteristics, while the metal mesh shielding layer 22 and the metal-plated carbon fiber layer 23 suppress high-frequency electromagnetic waves (>10MHz) through conductive reflection. The combination of the two forms a synergistic system of "magnetic loss absorption + electrical reflection shielding", extending the shielding frequency band from 10MHz to 10GHz of a single metal layer to 100kHz to 10GHz, and improving the shielding effectiveness by 10 to 20dB across the entire frequency band (e.g., the shielding effectiveness increases from 50dB to 70dB at 1MHz). As an intermediate transition layer, the ferrite thin film layer can reduce the electromagnetic reflection interface between the metal mesh and the metal-plated layer, reduce the multiple reflection losses of electromagnetic waves between layers, and weaken the energy of electromagnetic waves through magnetic loss, forming a cyclic shielding path of "incident wave → ferrite absorption → metal layer reflection → residual wave re-absorption", thereby improving the anti-interference capability in complex electromagnetic environments.

[0063] In the above embodiments, the metallized carbon fiber layer 23 is a nickel-plated carbon fiber layer or a silver-plated carbon fiber layer. The electrical conductivity of nickel is approximately 1.4 × 10⁻⁶. 7 With a resistivity of S / m, a nickel-plated layer (thickness ≥ 5 μm) can form a continuous conductive layer on the carbon fiber surface, resulting in a low sheet resistance of the metal-plated carbon fiber layer 23. This effectively reflects mid-to-high frequency electromagnetic waves (10 MHz to 10 GHz), achieving a shielding effectiveness ≥ 70 dB. Furthermore, nickel is less expensive than silver, making it suitable for mass production. Silver has a conductivity as high as 6.3 × 10⁻⁶. 7 The silver plating layer (thickness ≥3μm) allows the sheet resistance of the metal-plated carbon fiber layer 23 to reach a low value, resulting in minimal reflection loss of high-frequency electromagnetic waves (>1GHz) and a shielding effectiveness ≥90dB. It is especially suitable for scenarios with stringent high-frequency shielding requirements, such as 5G communication and radar equipment.

[0064] In the above embodiments, the metal mesh shielding layer 22 is one of copper wire mesh, nickel-plated copper mesh, stainless steel wire mesh, or aluminum-magnesium alloy wire mesh. Copper wire mesh has the lowest cost and is suitable for consumer electronics and general industrial equipment; nickel-plated copper mesh increases the cost by 15% to 20%, but improves corrosion resistance and is suitable for medium protection scenarios; stainless steel wire mesh costs 2 to 3 times that of copper mesh and is suitable for high reliability requirements (such as military and aerospace); aluminum-magnesium alloy wire mesh has a cost close to that of stainless steel, but has a significant advantage in lightweight design and is suitable for the aerospace field.

[0065] In this embodiment, the outer surface of the carbon fiber composite cover plate 20 is a flat, closed structure without heat dissipation grooves. The flat surface, without any unevenness, reduces the coupling area between external electromagnetic fields and the cover plate surface (reducing coupling capacitance by 30%–40%), preventing strong external electromagnetic pulses (such as lightning and EMP) from coupling into the chassis through the gaps in the heat dissipation grooves, thus protecting sensitive electronic components. The groove-free design avoids cutting and damaging the carbon fiber layers, maintaining the integrity and continuity of the fiber layup (fiber orientation consistency ≥95%), increasing the cover plate's bending strength by 20%, and significantly enhancing its impact resistance (e.g., drop hammer impact energy ≥5J), allowing it to withstand 100 kg / m². 2 It does not deform under external pressure and is suitable for harsh mechanical environments such as aerospace.

[0066] In traditional solutions, the sealing strip needs to achieve conductive connection at both the frame and the metal mesh shielding layer. Failure at any point in this conductive path will lead to electromagnetic leakage. In this solution, the annular sealing strip 25 is integrally formed with the carbon fiber composite cover plate 20. A conductive contact surface is formed on the annular sealing strip 25 by extending the metal mesh shielding layer 22 from within the carbon fiber composite cover plate 20. The annular sealing strip 25 and the carbon fiber composite cover plate 20 are integrally formed, and the metal mesh shielding layer 22 extends to form the conductive contact surface. After being pressed against the annular sealing groove 11 of the metal frame 10, it replaces the traditional independent conductive sealing strip. This application simplifies the dual-interface conductivity to a single-interface conductivity by directly extending the metal mesh shielding layer to form the conductive contact surface and pressing it against the inner wall of the annular sealing groove of the metal frame. This significantly improves reliability, and the shielding effectiveness remains at a high level even after long-term use.

[0067] When connecting the carbon fiber composite cover plate 20 to the metal frame 10, the traditional bolt connection is abandoned. The carbon fiber composite cover plate 20 and the metal frame 10 can be fixedly connected by pressing the annular sealing strip 25 and the annular sealing groove 11. Alternatively, conductive adhesive can be applied to the annular sealing strip 25 to achieve bonding and pressing between the two. A permanent magnet 30 can also be set between the carbon fiber composite cover plate 20 and the metal frame 10 for magnetic attraction connection, avoiding high-frequency electromagnetic wave leakage caused by bolt hole gaps. At the same time, tool-free rapid assembly is achieved, improving assembly efficiency.

[0068] The above description is only a specific embodiment of the present utility model, but the technical features of the present utility model are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present utility model are covered by the patent scope of the present utility model.

Claims

1. An electromechanical control enclosure, comprising a metal frame and a carbon fiber composite cover plate, wherein the carbon fiber composite cover plate includes a metal mesh shielding layer, characterized in that: The end face of the carbon fiber composite cover plate facing the metal frame is provided with an annular sealing strip protruding from the surface of the carbon fiber composite cover plate. The annular sealing strip is integrally formed with the carbon fiber composite cover plate and includes a conductive contact surface formed by extending outward from the metal mesh shielding layer and being exposed. The metal frame is provided with an annular sealing groove that matches the annular sealing strip. The outer wall of the annular sealing strip is tightly fitted with the inner wall of the annular sealing groove to form a structural seal. The conductive contact surface contacts the inner wall of the annular sealing groove to form a conductive connection.

2. The electromechanical control chassis according to claim 1, characterized in that: The metal frame and carbon fiber composite cover plate are embedded with permanent magnets that are magnetically connected to the metal frame.

3. The electromechanical control chassis according to claim 1, characterized in that: The annular sealing strip and the annular sealing groove are bonded and fixed together by applying conductive adhesive, and after curing, they form a seamless conductive connection.

4. The electromechanical control chassis according to claim 3, characterized in that: The conductive adhesive is a silver paste conductive adhesive.

5. The electromechanical control chassis according to claim 1, characterized in that: The carbon fiber composite cover plate includes a first carbon fiber layer, a metal mesh shielding layer, a metal-plated carbon fiber layer, and a second carbon fiber layer stacked in sequence, and the metal mesh shielding layer extends through the first carbon fiber layer and is exposed to form a conductive contact surface.

6. The electromechanical control chassis according to claim 5, characterized in that: The thickness of the first carbon fiber layer and the second carbon fiber layer is 0.56 mm, the thickness of the metal-plated carbon fiber layer is 0.8 mm, and the thickness of the metal mesh shielding layer is 0.08 mm.

7. The electromechanical control chassis according to claim 5, characterized in that: A ferrite film layer is also provided between the metal mesh shielding layer and the metal-plated carbon fiber layer.

8. The electromechanical control chassis according to claim 5, characterized in that: The metal-plated carbon fiber layer is either a nickel-plated carbon fiber layer or a silver-plated carbon fiber layer.

9. The electromechanical control chassis according to claim 1, characterized in that: The outer surface of the carbon fiber composite cover plate is a flat, closed structure without heat dissipation grooves.

10. The electromechanical control chassis according to claim 1, characterized in that: The metal mesh shielding layer is one of copper wire mesh, nickel-plated copper mesh, stainless steel wire mesh, or aluminum-magnesium alloy wire mesh.

Images