CN102636671B - Anechoic chamber with low frequency shielding property - Google Patents
Anechoic chamber with low frequency shielding property Download PDFInfo
- Publication number
- CN102636671B CN102636671B CN201210123815.XA CN201210123815A CN102636671B CN 102636671 B CN102636671 B CN 102636671B CN 201210123815 A CN201210123815 A CN 201210123815A CN 102636671 B CN102636671 B CN 102636671B
- Authority
- CN
- China
- Prior art keywords
- anechoic chamber
- steel plate
- low frequency
- shielding
- gap
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
The invention relates to an anechoic chamber with low frequency shielding property. The anechoic chamber is of a bilayer shielding structure formed by an inner layer and an outer layer, wherein the inner layer is formed by sequentially laminating a steel plate (1), a shielding material (11), a wave absorbing material and a wave transmitting plate (1.2), leakage of a low frequency electromagnetic field can be effectively avoided, attenuation of the low frequency electromagnetic field is increased, technical indexes of the anechoic chamber in the field of low frequency are obviously improved, the anechoic chamber is simple and feasible, construction cost of the anechoic chamber is reduced, and the anechoic chamber has relatively good cost performance and promotional value.
Description
Technical field
The invention belongs to a kind of low frequency shielding properties anechoic chamber,, especially there is the technical field of structures of the anechoic chamber, of excellent low frequency shielding properties.
Background technology
Present shielded anechoic chamber kind has a variety of, as fully anechoic chamber, semi-anechoic chamber, the also promising other types darkroom that meets test request and design, although the test event in different darkrooms is different, but generally include housing shroud housing, outer casing inner wall is in conjunction with one deck absorbing material layer, dark-room door, be arranged on turntable and the bracing or strutting arrangement thereof of the equipment under test in darkroom, antenna holder system, ventilation light fixture, wave filter, ground connection, safety and electrical equipment, surveying instrument and for interface board of being connected with surveying instrument etc., the test of conduction interference transmitting pre-value, the test of radiation disturbance transmitting pre-value, the EMC test such as radiation disturbance immunity experiment all require to carry out in anechoic chamber, but along with the development of absorbing material technology, the absorption loss that is more than or equal to 30MHz frequency electromagnetic waves can very ideally solve, damping capacity is more than 100dB, and be difficult to accomplish 100dB for the electromagnetic wave attenuation amount between 100kHz-30MHz.
Summary of the invention
The object of the invention is the weak point existing for overcoming above-mentioned prior art, provide a kind of can be between 100kHz-30MHz electromagnetic wave attenuation amount reach the anechoic chamber, of 100dB, be not only applicable to the performance requirement of semi-anechoic chamber, and be applicable to the performance requirement of fully anechoic chamber, and can significantly reduce anechoic chamber design cost, increase operation rate.
The technical solution used in the present invention is as follows: whole darkroom is set to by internal layer and the outer double-layer shielding structure forming; Wherein: internal layer adopts steel plate, shielding material, absorbing material and wave transparent plate sequentially to overlap, steel plate is sealed to an entirety with anechoic chamber, floor in anechoic chamber,, shielding material is mainly used to increase the absorption loss of frequency between 30MHz-100MHz frequency, and absorbing material mainly increases frequency is more than or equal to the electromagnetic absorption loss of 100MHz; Skin is made up of steel plate and shielding material, and steel plate is sealed to an entirety with anechoic chamber, floor in anechoic chamber,, and shielding material adopts the NiZn Ferrite Material with high magnetic loss angle tangent to form.
Inner layer steel plate and outer layer plate and anechoic chamber, floor is soldered is connected together, anechoic chamber, floor is connected with the earth earth potential by the mode of single-point grounding.Inner layer steel plate and shielding material adopt screw to be fixed together, and add the plastic cap nut that does not produce reflection in screw head.Gap between absorbing material and wave transparent plate gap is each other greater than 0.05mm after installing, and is less than 0.2mm, is preferably 0.1mm.The thickness of shielding material own is more than or equal to 5.5mm, is less than or equal to 6.5mm.After shielding material is installed and the gap of another adjacent piece shielding material is less than or equal to 0.2mm.Outer layer plate and shielding material adopt screw to be fixed together, and add the plastic cap nut that does not produce reflection in screw head.
Beneficial effect of the present invention is:
1, after adopting double layer screen to process, can effectively avoid the leakage of low frequency electromagnetic field;
2, increase the damping capacity of low frequency electromagnetic field;
3, significantly improve the technical indicator of darkroom in low frequency field;
4, easy, feasible, the construction cost of reduction anechoic chamber,, has good cost performance and promotional value.
Further illustrate the present invention below in conjunction with accompanying drawing and form and embodiment.
Brief description of the drawings
Fig. 1 is dual shield inner structure scheme of installation;
Fig. 2 is NiZn ferrite gap and the relation curve of inhaling ripple shielding character;
Fig. 3 is NiZn ferrite thickness and the relation curve of inhaling ripple shielding character;
Fig. 4 is the floor map of steel plate 2;
Fig. 5 is the floor map of steel plate 1.
Embodiment
For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with accompanying drawing, the present invention is described in further detail.
As shown in Figure 1, double layer screen of the present invention has 7 parts and forms, comprise outer shielding steel plate, steel plate 2, shielding material 2, steel plate 1, shielding material 1, absorbing material and wave transparent plate form, outer shielding steel plate is the outermost layer structure of anechoic chamber, lay steel plate 2 in the skin shielding steel plate inner side through four sides bending, use self threading pin that steel plate 2 is fixed on outer shielding bending steel plate, then ferrite wave-absorbing material is used screw to be fixed on steel plate 2, add the plastic cap nut that does not produce reflection in screw head, wherein in every 600mm*600mm region, there are 4 screw height higher than other screws, be used for mounting spliting type absorbing material, two screw symmetries in other two screws and picture, to ensure the neat and stability of spliting type absorbing material.Ferrite wave-absorbing material adopts and mounts mode, and every ferrite all uses screw that ferrite module is fixed in shield on steel plate 1, and on screw, adds plastic cap to prevent reflection.When installation, engineering construction aspect is by the gap of strictly controlling between ferrite, guarantee shielding material 1 install after gap be each other greater than 0.05mm, be less than 0.2mm, be preferably 0.1mm, shielding material 2 gap is each other less than or equal to 0.2mm after installing, covering is installed and reaches 100% full laying, on wedge wave absorbing material, cover white wave transparent plate, to beautify internal environment and to increase brightness.
As shown in Figure 2, from NiZn ferrite gap and the relation curve of inhaling ripple shielding character, shielding material thickness is thicker, reflection loss is less, not more that we wish the result obtaining, when thickness is for being more than or equal to 0.2mm, while being less than or equal to 0.5mm, basic shielding attenuation does not meet the requirements, but it is too high to the quality requirements of construction and installation that gap is less than after 0.05mm, make to construction and bring very large difficulty, thereby consider, shielding material 1 gap is each other greater than 0.05mm after installing, be less than 0.2mm, be preferably 0.1mm, shielding material 2 gap is each other less than or equal to 0.2mm after installing.
As shown in Fig. 3, table 1, table 2, from NiZn ferrite thickness and the relation curve of inhaling ripple shielding character, the internal layer of basic double layer screen can be accomplished 100dB by electromagnetic wave attenuation amount more than 30MHz, the skin of double layer screen shields 2 thickness and is more than or equal to 5.5mm, be less than or equal to 6.5mm and low frequency can be accomplished to 100kHz, in conjunction with the feature of double layer screen, 100kHz damping capacity is accomplished to 100dB simultaneously, meet the more better damping capacity of low frequency.
Steel plate 1 and shielding material 1.1 adopt screw to be fixed together, steel plate 2 and shielding material 2.2 adopt screw to be fixed together, as known in Fig. 4, Fig. 5, the spacing of steel plate 1 screwing is obviously little than the spacing of steel plate 2 screwings, and on steel plate 1, under the condition of same area, the density of screw is larger.
Table 1 is the technical indicator of common anechoic chamber,
| Frequency | Shielding attenuation | |
| 30MHz | ≥70dB | Magnetic field |
| 100MHz | ≥100dB | Plane wave |
| 500MHz | ≥100dB | Plane wave |
| 1GHz | ≥100dB | Plane wave |
| 18GHz | ≥100dB | Microwave |
Table 2 is technical indicators that anechoic chamber, of the present invention can reach
| Frequency | Shielding attenuation | |
| 100kHz | ≥100dB | Magnetic field |
| 1MHz | ≥100dB | Magnetic field |
| 30MHz | ≥100dB | Magnetic field |
| 100MHz | ≥100dB | Plane wave |
| 500MHz | ≥100dB | Plane wave |
| 1GHz | ≥100dB | Plane wave |
| 18GHz | ≥100dB | Microwave |
Claims (7)
1. an anechoic chamber, for low frequency shielding properties, is characterized in that: whole darkroom is set to by internal layer and the outer double-layer shielding structure forming; Wherein: internal layer adopts the first steel plate (1), the first shielding material (1.1), absorbing material and wave transparent plate (1.2) sequentially to overlap; the first steel plate (1) is sealed to an entirety with anechoic chamber, floor in anechoic chamber; the first shielding material (1.1) is mainly used to increase the absorption loss of frequency between 30MHz-100MHz frequency, and absorbing material mainly increases frequency is more than or equal to the electromagnetic absorption loss of 100MHz; Skin is made up of the second steel plate (2) and secondary shielding material (2.2); the second steel plate (2) is sealed to an entirety with anechoic chamber, floor in anechoic chamber,, and secondary shielding material (2.2) adopts the NiZn Ferrite Material with high magnetic loss angle tangent to form; Gap between absorbing material and wave transparent plate (1.2) gap is each other greater than 0.05mm after installing, and is less than the thickness of 0.2mm secondary shielding material (2.2) own and is more than or equal to 5.5mm, is less than or equal to 6.5mm.
2. the anechoic chamber, of a kind of low frequency shielding properties according to claim 1, it is characterized in that: the first steel plate (1) and the second steel plate (2) are connected together with anechoic chamber, floor is soldered, and anechoic chamber, floor is connected with the earth earth potential by the mode of single-point grounding.
3. the anechoic chamber, of a kind of low frequency shielding properties according to claim 1 and 2, is characterized in that: the first steel plate (1) and the first shielding material (1.1) adopt screw to be fixed together, and add the plastic cap nut that does not produce reflection in screw head.
4. the anechoic chamber, of a kind of low frequency shielding properties according to claim 1, is characterized in that: after secondary shielding material (2.2) is installed and the gap of another adjacent piece shielding material is less than or equal to 0.2mm.
5. the anechoic chamber, of a kind of low frequency shielding properties according to claim 1, is characterized in that: the second steel plate (2) and secondary shielding material (2.2) adopt screw to be fixed together, and add the plastic cap nut that does not produce reflection in screw head.
6. the anechoic chamber, of a kind of low frequency shielding properties according to claim 1, is characterized in that: the first steel plate (1) screwing gap ratio the second steel plate (2) screwing spacing is little.
7. the anechoic chamber, of a kind of low frequency shielding properties according to claim 1, is characterized in that: gap between absorbing material and wave transparent plate (1.2) gap is each other preferably 0.1mm after installing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210123815.XA CN102636671B (en) | 2012-04-25 | 2012-04-25 | Anechoic chamber with low frequency shielding property |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210123815.XA CN102636671B (en) | 2012-04-25 | 2012-04-25 | Anechoic chamber with low frequency shielding property |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102636671A CN102636671A (en) | 2012-08-15 |
| CN102636671B true CN102636671B (en) | 2014-08-27 |
Family
ID=46621140
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210123815.XA Active CN102636671B (en) | 2012-04-25 | 2012-04-25 | Anechoic chamber with low frequency shielding property |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102636671B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102944800B (en) * | 2012-11-30 | 2015-04-22 | 中国西电电气股份有限公司 | High-voltage electrical appliance electromagnetic radiation emission type testing system |
| CN109640613A (en) * | 2018-12-12 | 2019-04-16 | 许露敏 | A kind of reply New-energy electric vehicle EMC way to solve the problem |
| CN110231502A (en) * | 2019-04-30 | 2019-09-13 | 无锡敬仁电子材料科技有限公司 | A kind of anechoic chamber, improves the new structure of darkroom performance |
| CN111163625B (en) * | 2020-01-08 | 2022-05-13 | 李志宏 | Semi-anechoic chamber and floor structure thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2874722Y (en) * | 2005-09-23 | 2007-02-28 | 宝钢集团上海五钢有限公司 | Super low frequency electromagnet shielding device of multilay composite structure |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4909832B2 (en) * | 2007-07-18 | 2012-04-04 | Ｔｄｋ株式会社 | Radio wave absorber and radio wave anechoic chamber using the same |
| JP4752934B2 (en) * | 2009-03-05 | 2011-08-17 | Ｔｄｋ株式会社 | Radio wave absorber and manufacturing method thereof |
| WO2011016109A1 (en) * | 2009-08-04 | 2011-02-10 | 株式会社リケン | Wave absorber |
| KR101134202B1 (en) * | 2010-04-13 | 2012-04-09 | 고려대학교 산학협력단 | anechoic chamber having ferrite resonator |
-
2012
- 2012-04-25 CN CN201210123815.XA patent/CN102636671B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2874722Y (en) * | 2005-09-23 | 2007-02-28 | 宝钢集团上海五钢有限公司 | Super low frequency electromagnet shielding device of multilay composite structure |
Non-Patent Citations (2)
| Title |
|---|
| JP特开2009-26837A 2009.02.05 |
| JP特开2010-206064A 2010.09.16 |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102636671A (en) | 2012-08-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102636671B (en) | Anechoic chamber with low frequency shielding property | |
| CN204498078U (en) | Ultra broadband shielded enclosure power-supply filter | |
| US8987610B2 (en) | Vent structure for electromagnetic shielding | |
| EP2703964B1 (en) | Touch-control screen and mobile communications device | |
| CN205266129U (en) | PCB electromagnetic shield box | |
| CN102900164B (en) | Radiation-resistant acoustic board and production method thereof | |
| CN203774458U (en) | Small radio frequency directional antenna used for smart grid | |
| CN100593966C (en) | Electromagnetic wave shielding method and electromagnetic wave shielding cover | |
| CN104200078A (en) | Method for restraining electromagnetic interference (EMI) | |
| CN204538375U (en) | A kind of shielding construction for connector supply socket | |
| JP2009212187A (en) | Electronic control device | |
| CN205272705U (en) | Compound absorbing material | |
| CN203193504U (en) | Power supply adapter for proofing information leakage | |
| CN204392771U (en) | A kind of for communication terminal casing electromagnetic armouring structure | |
| CN102254595A (en) | Signal cable | |
| CN201590084U (en) | Computer interface capable of preventing information leaked | |
| CN204652865U (en) | A kind of radio shielding box body | |
| CN204104286U (en) | A kind of suction ripple radome | |
| CN204696011U (en) | A kind of electromagnetic armouring structure for keyboard | |
| CN202838101U (en) | Novel computer main board insulation sheet | |
| CN203011444U (en) | High-frequency electromagnetic interference preventing device of electromagnetic flowmeter | |
| CN201821635U (en) | Novel magnetic shielding device | |
| CN203423897U (en) | Device for preventing electromagnetic radiation of satellite power amplifier | |
| CN206236776U (en) | A kind of attachment structure of air environment and antenna | |
| CN104563576A (en) | Shielded room |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |