Electromagnetic shielding chamber special for aviation product EMC test

Abstract

The invention provides an electromagnetic shielding room special for an aviation product EMC test, and relates to the technical field of electromagnetic shielding rooms, the electromagnetic shielding room comprises a shielding shell, a manual shielding door and a ventilation waveguide window, the manual shielding door is arranged on the shielding shell for debugging personnel to go in and out, and the ventilation waveguide window is arranged on the shielding shell. The ventilation waveguide windows are installed on the side wall face and the top of the shielding shell respectively to achieve ventilation and electromagnetic shielding, the shielding shell is further provided with an overhaul shielding door and a filter, and the overhaul shielding door is used for connection and overhaul of cables in the shielding shell. During use, high-quality 2mm double-sided hot-dip galvanized steel plates are adopted for splicing, high-quality conductive gaskets are used for connecting splicing positions, so that good conductivity is guaranteed, high shielding performance is achieved, meanwhile, a filter is arranged for connecting cables entering and exiting the shielding shell, high-frequency signal components in a circuit are filtered out, a ventilation waveguide window with the cut-off frequency being 18 GHz is configured, and the shielding performance is improved. And the test requirements of aviation products with the working frequency range of 10kHz-18GHz floor noise are met.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic shielding rooms, and in particular to an electromagnetic shielding room dedicated to EMC testing of aviation products. Background Art

[0002] The electromagnetic shielding room is an important part of the electromagnetic compatibility (EMC) field. The electromagnetic shielding room is a steel plate house, and the cold-rolled steel plate is its main shielding material. It includes six-sided shells, doors, windows and other general house elements, but only requires strict electromagnetic sealing performance, and corresponding shielding treatment is performed on all inlet and outlet pipelines to block the entry and exit of electromagnetic radiation.

[0003] Existing shielded boxes or rooms are not designed specifically for aviation equipment testing; In radiation emission experiments, the interference signals of auxiliary equipment are complex and the overall shielding effect is poor, which cannot meet the requirements of noise floor testing in the operating frequency range of 10kHz to 18GHz. In radiation immunity experiments, sensitive equipment in auxiliary equipment is easily interfered with, which affects / cannot accurately determine the performance of the equipment under test.

[0004] To this end, the present application proposes an electromagnetic shielding room dedicated to EMC testing of aviation products, which is used to isolate the electromagnetic environment inside and outside the shielding room and is an ideal electromagnetic shielding room designed for aviation equipment testing. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide an electromagnetic shielding room dedicated to EMC testing of aviation products, so as to solve the problem in the prior art that there is no electromagnetic shielding room dedicated to aviation.

[0006] To achieve the above-mentioned object and other related objects, the present invention provides an electromagnetic shielding room dedicated to EMC testing of aviation products, comprising a shielding shell, a manual shielding door and a ventilation waveguide window, wherein the manual shielding door is arranged on the shielding shell for debugging personnel to enter and exit; The ventilation waveguide windows are respectively installed on the side wall and the top of the shielding shell to achieve ventilation and electromagnetic shielding; The shielding shell is also provided with a maintenance shielding door and a filter, wherein the maintenance shielding door is used for connecting and repairing the cables inside the shielding shell; and the filter is used for filtering out high-frequency signal components in the circuit. The shielding shell is formed by splicing a plurality of galvanized steel plates, and the four sides of the shielding shell are bent to form inwardly curved reinforcing ribs, and mounting keels are arranged between the inwardly curved reinforcing ribs; The manual shielding door comprises a door frame and a shielding door, the door frame and the shielding door are hinged, a double-blade four-spring lock is installed on the shielding door, and when the double-blade four-spring lock is locked, the blade can be embedded in the door frame, and a shielding reflection part is arranged on one side of the shielding door facing the inside of the shielding shell; The cutoff frequency of the ventilated waveguide window is 18 GHz; All filters have insertion loss better than 100dB in the frequency range of 10kHz-40GHz.

[0007] Preferably, the thickness of the galvanized steel sheet is 2 mm, and the thickness of the zinc coating of the galvanized steel sheet is not less than 20 μm.

[0008] Preferably, a conductive gasket is provided between any two adjacent galvanized steel plates to connect them.

[0009] Preferably, the blades and springs of the double-blade four-spring lock are tightly connected, and the springs are fixed to the door frame by bolts.

[0010] Preferably, the shielding door comprises a reflective layer and an isolation layer, wherein the reflective layer covers the outer surface of the isolation layer, an active cavity is provided between the isolation layers, and the active part of the double-blade four-spring lock is installed inside the active cavity.

[0011] Preferably, the ventilation waveguide window comprises a window edge frame and a waveguide matrix, wherein the waveguide matrix is ​​installed inside the window edge frame and is formed by welding hexagonal metal tubes.

[0012] Preferably, the hexagonal metal tubes constituting the waveguide matrix are connected by vacuum brazing, and the waveguide matrix has a shielding performance better than 100 dB in the frequency range of 10 kHz to 18 GHz.

[0013] Preferably, the ventilation waveguide window at the top is installed above the heat dissipation part of the equipment inside the shielding shell.

[0014] Preferably, the filter is mounted on the wall surface of the galvanized steel plate, and all cables entering and exiting the shielding shell are connected through the filter.

[0015] Preferably, a base frame is provided at the bottom of the shielding shell, and the base frame includes a bracket connected to the bottom of the shielding shell and a universal wheel installed at the bottom of the bracket.

[0016] As described above, the electromagnetic shielding room dedicated to EMC testing of aviation products of the present invention has the following beneficial effects: 1. The present invention adopts high-quality 2mm double-sided hot-dip galvanized steel plates for splicing, and uses high-quality conductive pads to connect the splicing to ensure good conductivity and achieve high shielding performance. At the same time, a filter is set to connect the cables entering and exiting the shielding shell to filter out the high-frequency signal components in the line, and a ventilated waveguide window with a cutoff frequency of 18GHz is configured to meet the testing requirements of aviation products with an operating frequency range of 10kHz to 18GHz background noise.

[0017] 2. The present invention provides a shielding door with a double-blade four-spring lock and adopts an inserted high-performance double-blade four-spring revolving door. The blades and the springs are tightly connected to improve the shielding effect. An inspection shielding door is provided for the connection and inspection of the cables inside the shielding shell. The manual shielding door and the inspection shielding door are both set to a frequency range of 10kHz~18GHz. The shielding efficiency meets the military standard C level, thereby further improving the shielding effect.

[0018] 3. The ventilation waveguide window of the present invention is composed of a hexagonal metal waveguide matrix and adopts vacuum brazing technology. The waveguide matrix has a certain length, that is, the ventilation waveguide window has a certain thickness. It relies on multiple reflections of electromagnetic waves in the ventilation waveguide window to ensure that the electromagnetic wave attenuation meets the requirements and at the same time ensure good indoor ventilation.

[0019] 4. The present invention provides a base frame at the bottom of the shielding shell and provides universal wheels for support, so that the shielding shell can be easily moved, thereby improving the convenience of use.

[0020] Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Shown is a schematic structural diagram of the present invention.

[0022] Figure 2 Shown is a side view of the structure of the present invention.

[0023] Figure 3 Shown is a partial structural schematic diagram of the shielding shell of the present invention.

[0024] Figure 4 Shown is a schematic structural diagram of the manual shielding door of the present invention.

[0025] Figure 5 Shown is a structural side view of the manual shielding door of the present invention.

[0026] Figure 6 Shown is a structural cross-sectional view of the shielding door of the present invention.

[0027] Figure 7 Shown is a schematic structural diagram of the ventilation waveguide window of the present invention.

[0028] Figure 8 Shown is a schematic three-dimensional structure diagram of the ventilation waveguide window of the present invention.

[0029] Fig. 9 Shown is a test schematic diagram of the filter of the present invention.

[0030] Component number description 1. Shielding shell; 101. Galvanized steel plate; 102. Inward bending reinforcement rib; 103. Install keel; 2. Manual shielding door; 201. Door frame; 202. Shielding door; 2021. Reflection layer; 2022. Isolation layer; 2023. Movable cavity; 203. Double-blade four-spring lock; 204. Shielding reflection part; 3. Maintenance shielding door; 4. Ventilation waveguide window; 401. Window edge frame; 402. Waveguide matrix; 5. Filter; 6. Base frame. DETAILED DESCRIPTION

[0031] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0032] See also Figures 1 to 9 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0033] like Figure 1-Figure 9 As shown, the present invention provides an electromagnetic shielding room dedicated to EMC testing of aviation products, comprising a shielding shell 1, a manual shielding door 2 and a ventilation waveguide window 4. The manual shielding door 2 is arranged on the shielding shell 1 for debugging personnel to enter and exit. The ventilation waveguide window 4 is respectively installed on the side wall and the top of the shielding shell 1 to achieve ventilation and electromagnetic shielding.

[0034] The shielding shell 1 is also provided with a maintenance shielding door 3 and a filter 5. The maintenance shielding door 3 is used for connecting and maintaining the cables inside the shielding shell 1. The filter 5 is used to filter out high-frequency signal components in the line. Since the shielding room lighting, equipment power supply lines, and equipment and outdoor control and communication lines often carry high-frequency interference signals while transmitting useful signals, thus affecting the shielding shell 1's isolation effect on the electromagnetic field, all cables entering and exiting the shielding shell 1 must pass through the filter 5.

[0035] The shielding shell 1 is made of multiple galvanized steel plates 101. The thickness of the galvanized steel plate 101 is 2mm, and the thickness of the zinc coating of the galvanized steel plate 101 is not less than 20μm. The four sides of the shielding shell 1 are bent to form inner bending reinforcement ribs 102. The 50mm wide bending reinforcement provides installation holes and electrical installation inside the shielding shell 1, effectively preventing deformation. An installation keel 103 is arranged between the inner bending reinforcement ribs 102, which is also used to reinforce the inside of the shielding shell 1 and provide support for equipment installation. The galvanized steel plate 101 should be able to ensure the strength and stable structure of the steel plate. The two corners are fully welded and re-polished and rust-proofed. Holes are drilled at appropriate intervals at the connection, and high-quality self-locking screws are used to connect and tighten.

[0036] The manual shielding door 2 includes a door frame 201 and a shielding door 202. The door frame 201 and the shielding door 202 are hinged. When the shielding door 202 and the door frame 201 are closed together, the shielding shell 1 can be sealed to improve the shielding effect. In order to ensure the shielding efficiency, a double-blade four-spring lock 203 is installed on the shielding door 202. When the double-blade four-spring lock 203 is locked, the blade can be embedded in the interior of the door frame 201. The blade and the spring of the double-blade four-spring lock 203 are tightly connected. The spring is fixed to the door frame 201 by bolts and can be manually opened from the inside and outside of the shielding shell 1.

[0037] A shielding reflector 204 is disposed on one side of the shielding door 202 facing the inside of the shielding shell 1 . The shielding reflector 204 is made of an absorbing material and has an uneven surface for reducing reflection of electromagnetic waves.

[0038] The cutoff frequency of the ventilation waveguide window 4 is 18 GHz. The ventilation waveguide window 4 includes a window edge frame 401 and a waveguide matrix 402. The waveguide matrix 402 is installed inside the window edge frame 401. The waveguide matrix 402 is welded from hexagonal metal tubes and is used to achieve good ventilation and electromagnetic wave attenuation inside the shielding shell 1.

[0039] The filter 5 is installed on the wall of the galvanized steel plate 101, and all cables entering and exiting the shielding shell 1 are connected through the filter 5. Since the shielding shell 1 lighting, equipment power supply lines, equipment and outdoor control, communication lines, etc. often carry high-frequency interference signals while transmitting useful signals, the shielding shell 1's electromagnetic field isolation effect is affected. Therefore, all cables entering and exiting the shielding shell 1 must pass through the filter 5. The insertion loss test of the filter 5 used meets the requirements of CISPR publication 17 and MIL-STD 220A standards. All filters 5 have insertion losses better than 100dB in the frequency range of 10kHz-40GHz to ensure safe use.

[0040] In some embodiments, a conductive gasket is provided between any two adjacent galvanized steel plates 101 of the present invention to ensure good conductivity.

[0041] In some embodiments, the shielding door 202 of the present invention includes a reflective layer 2021 and an isolation layer 2022, wherein the reflective layer 2021 covers the outer surface of the isolation layer 2022, thereby improving the shielding effect of the shielding door 202 through the structure in addition to the material itself. An active cavity 2023 is provided between the isolation layers 2022, and the electromagnetic waves inside and outside will be greatly attenuated after passing through the reflective layer 2021, the isolation layer 2022 and the active cavity 2023, thereby achieving a shielding effect. The active part of the double-blade four-spring lock 203 is installed inside the active cavity 2023, so that when the handle is turned inside and outside the shielding shell 1, the movement of the blades of the double-blade four-spring lock 203 can be conveniently controlled.

[0042] In some embodiments, the hexagonal metal tubes constituting the waveguide matrix 402 of the present invention are connected by vacuum brazing, and the waveguide matrix 402 has a shielding performance better than 100 dB in the frequency range of 10 kHz to 18 GHz. The waveguide matrix 402 needs to have a certain length, that is, the ventilation waveguide window 4 has a certain thickness, and relies on the multiple reflections of electromagnetic waves inside the hexagonal metal tubes to ensure that the electromagnetic wave attenuation meets the requirements and ensures good indoor ventilation. Ensure that the temperature inside the shielding shell 1 is uniform without obvious gradients.

[0043] In some embodiments, the top ventilation waveguide window 4 of the present invention is installed above the heat dissipation part of the device inside the shielding shell 1 to dissipate the heat of the device inside the shielding shell 1. This reduces the heat dissipation path of the device and improves the directness and efficiency of heat dissipation.

[0044] In some embodiments, a base frame 6 is provided at the bottom of the shielding shell 1 of the present invention to support the shielding shell 1, so that the bottom of the shielding shell 1 is off the ground, thereby reducing the interference of the ground on the electromagnetic waves to the inside of the shielding shell 1. The base frame 6 includes a bracket connected to the bottom of the shielding shell 1 and a universal wheel installed at the bottom of the bracket, and the universal wheel can be used to conveniently push the entire shielding shell 1 to improve the convenience of using the device.

[0045] In summary, the electromagnetic shielding room of the present invention, which is specially used for EMC testing of aviation products, is spliced ​​by high-quality 2mm double-sided hot-dip galvanized steel plates 101, and the splicing is connected with high-quality conductive pads to ensure good conductivity and achieve high shielding performance. At the same time, a filter 5 is set to connect the cables entering and exiting the shielding shell 1 to filter out high-frequency signal components in the line, and a ventilated waveguide window 4 with a cutoff frequency of 18GHz is configured to meet the testing requirements of aviation products with an operating frequency range of 10kHz to 18GHz background noise.

[0046] By setting a shielding door 202 with a double-blade four-spring lock 203 and adopting an inserted high-performance double-blade four-spring revolving door, the blades and the springs are tightly connected to improve the shielding effect, and a maintenance shielding door 3 is set for the connection and maintenance of the cables inside the shielding shell 1, and the manual shielding door 2 and the maintenance shielding door 3 are both set to a frequency range of 10kHz~18GHz, and the shield efficiency meets the military standard C level, thereby further improving the shielding effect.

[0047] At the same time, the ventilation waveguide window 4 is composed of a hexagonal metal waveguide matrix 402, and adopts vacuum brazing technology. Its waveguide matrix 402 has a certain length, that is, the ventilation waveguide window 4 has a certain thickness. Relying on multiple reflections of electromagnetic waves in the ventilation waveguide window 4, it ensures that the electromagnetic wave attenuation meets the requirements and at the same time ensures good indoor ventilation.

[0048] By arranging a base frame 6 at the bottom of the shielding shell 1 and arranging universal wheels for support, the shielding shell 1 can be conveniently moved, thereby improving the convenience of use.

[0049] Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0050] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. An electromagnetic shielding room specially used for EMC testing of aviation products, comprising a shielding shell (1), a manual shielding door (2) and a ventilation waveguide window (4), characterized in that: The manual shielding door (2) is arranged on the shielding shell (1) for debugging personnel to enter and exit; The ventilation waveguide windows (4) are respectively installed on the side wall surface and the top of the shielding shell (1) to achieve ventilation and electromagnetic shielding; The shielding shell (1) is also provided with a maintenance shielding door (3) and a filter (5), respectively. The maintenance shielding door (3) is used for connecting and maintaining cables inside the shielding shell (1); the filter (5) is used for filtering out high-frequency signal components in the line. The shielding shell (1) is formed by splicing a plurality of galvanized steel plates (101); the four sides of the shielding shell (1) are bent to form inwardly curved reinforcing ribs (102); and mounting keels (103) are provided between the inwardly curved reinforcing ribs (102); The manual shielding door (2) comprises a door frame (201) and a shielding door (202); the door frame (201) and the shielding door (202) are hinged; a double-blade four-spring lock (203) is installed on the shielding door (202); when the double-blade four-spring lock (203) is locked, a blade can be embedded in the door frame (201); and a shielding reflection portion (204) is provided on a side of the shielding door (202) facing the inside of the shielding shell (1); The cut-off frequency of the ventilated waveguide window (4) is 18 GHz; All filters (5) have insertion losses better than 100dB in the frequency range of 10kHz-40GHz.

2. The electromagnetic shielding room dedicated to EMC testing of aviation products according to claim 1 is characterized by: The thickness of the galvanized steel sheet (101) is 2 mm, and the thickness of the zinc coating of the galvanized steel sheet (101) is not less than 20 μm.

3. The electromagnetic shielding room dedicated to EMC testing of aviation products according to claim 1 is characterized by: A conductive gasket is provided between any two adjacent galvanized steel plates (101) to connect them.

4. The electromagnetic shielding room dedicated to EMC testing of aviation products according to claim 1 is characterized by: The blades and the spring of the double-blade four-spring lock (203) are tightly connected, and the spring is fixed to the door frame (201) by bolts.

5. The electromagnetic shielding room dedicated to EMC testing of aviation products according to claim 4 is characterized in that: The shielding door (202) comprises a reflective layer (2021) and an isolation layer (2022); the reflective layer (2021) covers the outer surface of the isolation layer (2022); an active cavity (2023) is provided between the isolation layers (2022); and the active part of the double-blade four-spring lock (203) is installed inside the active cavity (2023).

6. The electromagnetic shielding room dedicated to EMC testing of aviation products according to claim 1 is characterized by: The ventilation waveguide window (4) comprises a window edge frame (401) and a waveguide matrix (402); the waveguide matrix (402) is installed inside the window edge frame (401); the waveguide matrix (402) is formed by welding hexagonal metal tubes.

7. The electromagnetic shielding room dedicated to EMC testing of aviation products according to claim 6, characterized in that: The hexagonal metal tubes constituting the waveguide matrix (402) are connected by vacuum brazing, and the waveguide matrix (402) has a shielding performance better than 100 dB in a frequency range of 10 kHz to 18 GHz.

8. The electromagnetic shielding room dedicated to EMC testing of aviation products according to claim 7, characterized in that: The ventilation waveguide window (4) at the top is installed above the heat dissipation part of the equipment inside the shielding shell (1).

9. The electromagnetic shielding room dedicated to EMC testing of aviation products according to claim 1, characterized in that: The filter (5) is mounted on the wall surface of the galvanized steel plate (101), and all cables entering and exiting the shielding shell (1) are connected via the filter (5).

10. The electromagnetic shielding room dedicated to EMC testing of aviation products according to any one of claims 1 to 9, characterized in that: A base frame (6) is provided at the bottom of the shielding shell (1), and the base frame (6) comprises a bracket connected to the bottom of the shielding shell (1) and a universal wheel installed at the bottom of the bracket.

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