Electromagnetic reverberation chamber stirring unit through-wall shielding device and reverberation chamber

Abstract

The utility model discloses an electromagnetic reverberation chamber stirring unit through-wall shielding device and a reverberation chamber, and belongs to the field of electromagnetic compatibility testing. The electromagnetic reverberation chamber stirring unit through-wall shielding device comprises a shielding box, wherein one end of a stirring shaft penetrates into the shielding box and penetrates out of the shielding box; the connecting ring is arranged between the shielding box and the stirring shaft, the connecting ring is fixedly connected with the shielding box, the connecting ring is rotatably connected with the stirring shaft, one end of the connecting ring penetrates into the reverberation chamber, and the outer wall of the shielding box is in shielding connection with the outer wall of the reverberation chamber. Through the combined design of the shielding box and the connecting ring, electromagnetic signals are effectively prevented from leaking from a gap between the stirring shaft and the reverberation chamber wall, the accuracy and repeatability of electromagnetic compatibility testing are improved, and the electromagnetic compatibility testing device is simple in structure, low in technical difficulty and low in cost.

Description

Technical Field

[0001] The present application relates to the field of electromagnetic compatibility testing, and in particular to a through-wall shielding device for a stirring unit of an electromagnetic reverberation chamber and a reverberation chamber. Background Art

[0002] As a key experimental facility for evaluating the electromagnetic compatibility performance of electronic equipment, the electromagnetic reverberation chamber simulates a complex electromagnetic environment by generating random multipath electromagnetic fields in a closed space to ensure that the equipment under test can work normally under various electromagnetic interference conditions. During this period, it is necessary to avoid electromagnetic signal leakage, especially to solve the problem of shielding signal leakage of moving parts during the test.

[0003] In traditional electromagnetic reverberation chambers, in order to achieve uniform electromagnetic field distribution, stirrers are often used to change the propagation path of electromagnetic waves in the reverberation chamber. However, the motor drive system and control circuit of the stirrer are usually located outside the reverberation chamber, which requires that the stirring shaft passing through the wall of the reverberation chamber and the shielding body must have good electromagnetic shielding effectiveness to prevent external interference from entering or indoor signal leakage, affecting the accuracy and repeatability of the test.

[0004] Existing similar technologies and problems are detailed as follows:

[0005] Sliding contact shielding structure: This technology achieves shielding effect by setting a slip ring or carbon brush contact point between the stirring shaft and the outside world. The slip ring or carbon brush allows current to pass while maintaining shielding continuity. This solution is only suitable for electromagnetic signal shielding in the low to medium frequency band. In addition, the structure is prone to wear and tear and has low shielding effectiveness. The use of high-quality conductive materials and precision processing technology are key factors affecting its quality and service life.

[0006] Waveguide penetration design: A special waveguide or coaxial transmission line structure is installed on the wall through which the stirring shaft passes, so that the stirring shaft becomes part of the waveguide. This method uses the cutoff frequency characteristics of the waveguide to effectively suppress electromagnetic leakage within a specific frequency range and is only suitable for high-frequency applications. The size, shape and terminal matching of the waveguide are key factors affecting shielding effectiveness.

[0007] Magnetic coupling technology: This technology avoids direct electrical connection and instead uses the principle of magnetic field coupling to transmit power. Contactless power transmission is achieved through the interaction between the external drive magnet and the magnetic rotor inside the stirrer. This design completely isolates electromagnetic interference, but may compromise power transmission efficiency and structural complexity.

[0008] Combination of non-metallic materials and shielding layer: non-conductive materials (such as ceramics or glass fiber reinforced plastics) are used as the main body of the stirring shaft, and a highly conductive shielding layer such as copper or silver is coated on its surface. Although this design can maintain the mechanical strength and insulation performance of the stirring shaft and effectively shield electromagnetic waves, it is expensive, has a long volume, requires a large space, and has high site requirements.

[0009] Elastic sealing and shielding composite structure: By designing an elastic sealing ring at the interface between the stirring shaft and the wall and wrapping multiple layers of shielding materials (such as metal foil, conductive fabric, etc.) on the periphery, it can prevent medium leakage and effectively block electromagnetic radiation. This structure requires high installation accuracy, high maintenance costs in the later stage, and low shielding effectiveness warranty.

[0010] Active shielding technology: Arrange one or more circles of active electromagnetic interference suppression devices around the stirring shaft, such as active noise cancellation circuits or electromagnetic field compensation systems. These systems monitor and generate reverse electromagnetic fields in real time to neutralize interference, and are suitable for occasions with extremely high shielding requirements, but the cost and technical difficulty are relatively high.

[0011] Regarding the above-mentioned related technologies, although the existing through-wall structure can solve the shielding problem to a certain extent, it still has limitations such as insufficient shielding effectiveness, complex installation, motor anti-interference failure, high cost, and difficult maintenance. Utility Model Content

[0012] In order to effectively solve the problem of shielding leakage caused by the stirring shaft passing through the shielding wall, to reduce the electromagnetic interference generated and to improve the shielding effectiveness of the external environment on the internal signal, the present application provides an electromagnetic reverberation chamber stirring unit through the wall shielding device and a reverberation chamber.

[0013] The present application provides a wall shielding device for a stirring unit in an electromagnetic reverberation chamber, which adopts the following technical solution:

[0014] A wall shielding device for a stirring unit in an electromagnetic reverberation chamber, comprising:

[0015] A shielding box, one end of the stirring shaft penetrates into the shielding box and passes through the shielding box;

[0016] A connecting ring is arranged between the shielding box and the stirring shaft, the connecting ring is fixedly connected to the shielding box, the connecting ring is rotatably connected to the stirring shaft, one end of the connecting ring penetrates into the reverberation chamber, and the outer wall of the shielding box is shieldedly connected to the outer wall of the reverberation chamber.

[0017] By adopting the above technical solution, the shielding box is fixedly connected to the wall of the reverberation chamber; a connecting ring is provided at one end of the shielding box, which is fixed to the shielding box and passes through the wall of the reverberation chamber; so that the electromagnetic signal is not easy to leak from there, and the electromagnetic signal can only enter the shielding box along the movable connection between the connecting ring and the stirring shaft, and the external signal can only enter the shielding box, thereby effectively solving the problem of shielding leakage caused by the stirring shaft passing through the shielding wall, reducing the electromagnetic interference generated at the stirring shaft and improving the shielding effectiveness of the external environment against the internal signal. The present application effectively prevents the electromagnetic signal from leaking from the gap between the stirring shaft and the wall of the reverberation chamber through the combined design of the shielding box and the connecting ring, improves the accuracy and repeatability of the electromagnetic compatibility test, and has a simple structure, low technical difficulty and low cost.

[0018] Optionally, the shielding box is filled with metal particles.

[0019] By adopting the above technical solution, several tiny holes will be formed between the metal particles (similar to the honeycomb principle) and arranged irregularly in the shielding box. The size and arrangement of these holes are determined by the size of the metal particles. The smaller the size of the metal particles, the better the effect of attenuating electromagnetic waves within the shielding electromagnetic frequency range. The principle is that the electromagnetic waves entering the shielding box can be absorbed by means of tiny holes, thereby further ensuring higher shielding effectiveness.

[0020] Optionally, a waveguide is provided on the outer periphery of the stirring shaft that penetrates into the shielding box, and one end of the waveguide is fixedly connected to one end of the connecting ring.

[0021] By adopting the above technical solution, the length and shape of the waveguide are specially designed according to the diameter of the stirring shaft and the size of the stirring shaft, which can effectively improve the electromagnetic shielding effectiveness.

[0022] Optionally, a side wall of the shielding box is provided with an opening, and a shielding cover is connected to the opening.

[0023] By adopting the above technical solution, the design of the shielding cover can facilitate maintenance and repair of the inside of the shielding box while maintaining the shielding effect.

[0024] Optionally, a side of the connecting ring facing away from the stirring shaft is fixedly connected to the wall of the shielding box, and a side of the connecting ring facing away from the stirring shaft is movably connected to the wall of the reverberation chamber.

[0025] By adopting the above technical solution, the connection point is kept away from the active connection part, and multi-layer shielding treatment is performed, which helps to further reduce the possibility of electromagnetic signal leakage. At the same time, it is also easier to connect the shielding box with the connecting ring and the reverberation chamber.

[0026] Optionally, a rotating bearing is provided between the connecting ring and the stirring shaft.

[0027] By adopting the above technical solution, the design of the rotating bearing can ensure the smooth rotation of the stirring shaft and reduce the electromagnetic interference caused by friction.

[0028] Optionally, a mounting groove is formed on one side of the connecting ring relative to the stirring shaft, the rotating bearing is installed in the mounting groove, and both end surfaces of the connecting ring are respectively located in the reverberation chamber and the shielding box.

[0029] By adopting the above technical solution, this design can ensure the stable installation of the rotating bearing while maintaining the shielding effect.

[0030] Optionally, the outer wall of the shielding box is welded or detachably connected to the outer wall of the reverberation chamber.

[0031] By adopting the above technical solution, the convenience of installation between the shielding device and the reverberation chamber is improved, and it is also convenient for later maintenance.

[0032] A reverberation chamber comprises the above-mentioned electromagnetic reverberation chamber stirring unit wall shielding device.

[0033] In summary, the present application includes at least one of the following beneficial technical effects:

[0034] 1. The combined design of the shielding box and the connecting ring effectively prevents the electromagnetic signal from leaking from the gap between the stirring shaft and the reverberation chamber wall, thereby improving the accuracy and repeatability of the electromagnetic compatibility test.

[0035] 2. The design of waveguide tube and metal particle filling further enhances the shielding effect and ensures the reliability of the test results.

[0036] 3. The shielding cover, the tightly connected connecting ring, and the shielding connection design between the shielding box and the outer wall of the reverberation chamber can improve the convenience of installation and maintenance of the shielding box while ensuring high shielding effectiveness.

[0037] 4. The design of the rotating bearing and mounting groove ensures the smooth rotation and stable installation of the stirring shaft, while reducing the electromagnetic interference caused by friction.

[0038] 5. The reverberation chamber using the shielding device of the present application has higher accuracy and reliability in electromagnetic compatibility testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the overall structure of Example 1 of the present application.

[0040] Figure 2 yes Figure 1 Enlarged schematic diagram of part A.

[0041] Figure 3It is a schematic diagram of the overall structure of Example 2 of the present application.

[0042] Description of reference numerals:

[0043] 10. Reverberation chamber; 11. Stirring shaft; 20. Shielding box; 21. Opening; 22. Shielding cover; 30. Connecting ring; 31. Mounting groove; 40. Metal particles; 50. Rotating bearing; 60. Waveguide. DETAILED DESCRIPTION

[0044] The following is combined with Figure 1-3 This application is described in further detail.

[0045] Example 1

[0046] like Figure 1 and Figure 2 As shown, the electromagnetic reverberation chamber stirring unit wall shielding device provided in the embodiment of the present application includes a shielding box 20 and a connecting ring 30. The shielding box 20 is a closed metal box used to prevent the leakage of electromagnetic signals. One end of the stirring shaft 11 penetrates into the shielding box 20 and passes through the shielding box 20, and can rotate freely in the shielding box 20. The connecting ring 30 is arranged between the shielding box 20 and the stirring shaft 11, and plays a role of connection and shielding. The connecting ring 30 is fixedly connected to the shielding box 20 and is rotatably connected to the stirring shaft 11, so that the stirring shaft 11 does not affect the shielding effect when rotating. One end of the connecting ring 30 penetrates into the reverberation chamber 10 and the outer wall of the shielding box 20 is shielded and connected to the outer wall of the reverberation chamber 10, ensuring the close fit between the outer wall of the shielding box 20 and the wall of the reverberation chamber 10 to prevent electromagnetic signals from leaking from the connection.

[0047] Specifically, the shielding box 20 is made of metal material and has good conductivity and shielding effectiveness. The shape and size of the shielding box 20 are designed according to actual needs and can adapt to stirring shafts 11 of different sizes and shapes. In this embodiment, the cross-section of the shielding box 20 is square. In other embodiments, the shielding box 20 can also be circular or polygonal.

[0048] The interior of the shielding box 20 is filled with metal particles 40. A number of tiny holes are formed between the metal particles 40 (similar to the honeycomb principle). The holes are irregularly arranged inside the shielding box 20. The size and arrangement of these holes are determined by the size of the metal particles 40. The smaller the size of the metal particles 40, the better the effect of attenuating electromagnetic waves within the shielding electromagnetic frequency range. The principle is that the electromagnetic waves entering the shielding box 20 can be absorbed by means of tiny holes, thereby further ensuring higher shielding effectiveness.

[0049] In order to facilitate filling and maintenance of the metal particles 40 inside the shielding box 20, in this embodiment, an opening 21 is further provided on the upper side of the shielding box 20, and a shielding cover 22 is connected to the opening 21. The shielding cover 22 can be made of metal material, and the shielding cover 22 can be connected to the shielding box 20 by bolt connection, which is convenient for opening and closing.

[0050] The connecting ring 30 is made of a conductive material, such as metal, to ensure a good shielding effect. The shape and size of the connecting ring 30 are also designed according to actual needs to adapt to the connection between the shielding box 20 and the stirring shaft 11.

[0051] The connecting ring 30 is provided with a mounting groove 31 on one side relative to the stirring shaft 11, and a rotating bearing 50 is installed in the mounting groove 31. The two end surfaces of the connecting ring 30 are respectively located in the reverberation chamber 10 and the shielding box 20. The rotating bearing 50 is arranged on the outer periphery of the stirring shaft 11 to ensure the smooth rotation of the stirring shaft 11. The rotating bearing 50 can be a standard bearing available on the market, or can be customized according to actual needs.

[0052] In this embodiment, connecting rings 30 are provided at both connecting points between the shielding box 20 and the stirring shaft 11 , and rotating bearings 50 are installed in the connecting rings 30 , so as to improve the rotation stability of the stirring shaft 11 .

[0053] In addition, the side of the connecting ring 30 away from the stirring shaft 11 is fixedly connected to the wall of the shielding box 20, the side of the connecting ring 30 away from the stirring shaft 11 is movably connected to the wall of the reverberation chamber 10, and the outer wall of the shielding box 20 is closely attached to the outer wall of the reverberation chamber 10 to achieve a shielding connection. Such a design can reduce the leakage of electromagnetic signals through the connecting ring 30, further reduce the leakage path of electromagnetic signals, and improve the shielding effect.

[0054] In addition, in this embodiment, the outer wall of the shielding box 20 is fixedly connected to the outer wall of the reverberation chamber 10, and can be connected by flange bolts or welding, which is convenient for installation and simple for subsequent maintenance.

[0055] The embodiment of the present application effectively prevents electromagnetic signals from leaking from the gap between the stirring shaft 11 and the wall of the reverberation chamber 10 through the combined design of the shielding box 20 and the connecting ring 30, thereby improving the accuracy and repeatability of the electromagnetic compatibility test.

[0056] Example 2

[0057] Reference Figure 3On the basis of Example 1, the electromagnetic reverberation chamber stirring unit through-wall shielding device provided in the embodiment of the present application may further include a waveguide 60. The waveguide 60 is sleeved on the outer periphery of the stirring shaft 11 penetrating into the shielding box 20, and one end of the waveguide 60 is fixedly connected to one end of the connecting ring 30. The design of the waveguide 60 can further prevent the leakage of electromagnetic signals and enhance the shielding effect.

[0058] Specifically, the waveguide 60 can be made of a metal material with good conductivity and shielding effectiveness. The shape and size of the waveguide 60 are designed according to actual needs to adapt to the connection between the stirring shaft 11 and the connecting ring 30. The waveguide 60 and the connecting ring 30 can be fixedly connected by welding or the like to ensure the stability of the connection and the shielding effect.

[0059] In this embodiment, the waveguide 60 is only provided on one side where the stirring shaft 11 passes through the shielding box 20. In other embodiments, the waveguide 60 may also be provided on the other side where the stirring shaft 11 passes through the shielding box 20, so as to reduce the gap between the stirring shaft 11 and the waveguide, effectively preventing the electromagnetic waves in the reverberation chamber 10 from leaking out, and also effectively preventing the electromagnetic waves outside from entering the reverberation chamber 10, thereby effectively improving the through-wall shielding effect.

[0060] In summary, the electromagnetic reverberation chamber stirring unit wall shielding device of the present application effectively prevents electromagnetic signals from leaking from the gap between the stirring shaft 11 and the wall of the reverberation chamber 10 through the design of the shielding box 20, the connecting ring 30, the waveguide 60 and other structures, thereby improving the accuracy and repeatability of the electromagnetic compatibility test. At the same time, the device has a simple structure, is easy to install, and has low maintenance costs, and has broad application prospects and market value.

[0061] Example 3

[0062] The embodiment of the present application also discloses a reverberation chamber, including the electromagnetic reverberation chamber stirring unit wall shielding device described in Example 1 or Example 2. In practical applications, the shielding device is installed at the wall of the stirring unit of the reverberation chamber 10, which can effectively prevent the electromagnetic signal from leaking from the gap between the stirring shaft 11 and the wall of the reverberation chamber 10, thereby improving the accuracy and reliability of the reverberation chamber 10 in electromagnetic compatibility testing. This reverberation chamber 10 is suitable for various products and equipment that need to be tested for electromagnetic compatibility, such as electronic equipment, communication equipment, automotive electronics, etc. By using the shielding device of the present application, the accuracy and credibility of the test results can be significantly improved, providing strong support for the research and development and production of products.

[0063] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A wall shielding device for a stirring unit in an electromagnetic reverberation chamber, characterized in that: include: A shielding box (20), one end of the stirring shaft (11) penetrates into the shielding box (20) and passes through the shielding box (20); A connecting ring (30) is arranged between the shielding box (20) and the stirring shaft (11); the connecting ring (30) is fixedly connected to the shielding box (20); the connecting ring (30) is rotatably connected to the stirring shaft (11); one end of the connecting ring (30) penetrates into the reverberation chamber (10); and the outer wall of the shielding box (20) is shieldedly connected to the outer wall of the reverberation chamber (10).

2. The electromagnetic reverberation chamber stirring unit wall shielding device according to claim 1, characterized in that: The shielding box (20) is filled with metal particles (40).

3. The electromagnetic reverberation chamber stirring unit wall shielding device according to claim 1, characterized in that: A waveguide tube (60) is sleeved on the outer periphery of the stirring shaft (11) that penetrates into the shielding box (20), and one end of the waveguide tube (60) is fixedly connected to one end of the connecting ring (30).

4. The electromagnetic reverberation chamber stirring unit wall shielding device according to claim 3, characterized in that: The side wall of the shielding box (20) is provided with an opening (21), and the opening (21) is connected to a shielding cover (22).

5. The electromagnetic reverberation chamber stirring unit wall shielding device according to claim 1, characterized in that: The side of the connecting ring (30) facing away from the stirring shaft (11) is fixedly connected to the wall of the shielding box (20), and the side of the connecting ring (30) facing away from the stirring shaft (11) is movably connected to the wall of the reverberation chamber (10).

6. The electromagnetic reverberation chamber stirring unit wall shielding device according to claim 1, characterized in that: A rotary bearing (50) is provided between the connecting ring (30) and the stirring shaft (11).

7. The electromagnetic reverberation chamber stirring unit wall shielding device according to claim 6, characterized in that: A mounting groove (31) is provided on one side of the connecting ring (30) relative to the stirring shaft (11), the rotating bearing (50) is mounted in the mounting groove (31), and both end surfaces of the connecting ring (30) are respectively located in the reverberation chamber (10) and in the shielding box (20).

8. The electromagnetic reverberation chamber stirring unit wall shielding device according to claim 1, characterized in that: The outer wall of the shielding box (20) is welded or detachably connected to the outer wall of the reverberation chamber (10).

9. A reverberation chamber, characterized in that: The invention comprises the wall shielding device for the stirring unit of the electromagnetic reverberation chamber according to any one of claims 1 to 8.

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