CN107167231A - A kind of interference shielding device measured for acoustic sensor self noise - Google Patents
A kind of interference shielding device measured for acoustic sensor self noise Download PDFInfo
- Publication number
- CN107167231A CN107167231A CN201710260829.9A CN201710260829A CN107167231A CN 107167231 A CN107167231 A CN 107167231A CN 201710260829 A CN201710260829 A CN 201710260829A CN 107167231 A CN107167231 A CN 107167231A
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- metal cabinet
- acoustic sensor
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- vacuum cylinder
- metal
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H17/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves, not provided for in the preceding groups
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- General Physics & Mathematics (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
The present invention describes a kind of interference shielding device measured for acoustic sensor self noise, belongs to field of sensor measurement, and the self noise for acoustic sensor is measured.A variety of interference that screening arrangement in the present invention is just used in Isolated Shield environment, include matrix platform, metal cabinet, vacuum cylinder and pumped vacuum systems, metal cabinet is placed on above matrix platform, vacuum cylinder is placed inside metal cabinet, tested acoustic sensor is arranged on inside vacuum cylinder, the lower end covered on vacuum cylinder is suspended on, tested acoustic sensor is connected by electric connector and cable with Noise Acquisition system；Pumped vacuum systems is located at the outside of metal cabinet, is connected between pumped vacuum systems and vacuum cylinder by flexible tracheae, and it is high vacuum state that flexible tracheae, which is passed through in the tank wall of metal cabinet, vacuum cylinder,.Beneficial effect of the present invention：There is significant shield effectiveness to vibration interference, sound wave interference and Electromagnetic Interference, can be measured effective for acoustic sensor self noise.
Description
Technical field
It is mainly a kind of to be used for what acoustic sensor self noise was measured the invention belongs to acoustic sensor parameter measurement field
Interference shielding device.
Background technology
The self noise of acoustic sensor is general all very low, in order to measure its self noise, it is desirable to have the stable acoustics of peace and quiet is surveyed
Measure environment, it is desirable to which a variety of interference of environment are far below self noise, especially highly sensitive sensor, vibratory response to external world
Very sensitive, the requirement to measuring condition is just very high, and is difficult to meet the requirement in the open place of reality, from various approach
Interference can not mostly exclude completely.
On the influential environmental disturbances of acoustic sensor self noise measurement mainly comprising vibration interference, sound wave interference and electromagnetism
Wave interference.The direct sources of vibration interference are exactly mainly the flooring residing for equipment, and secondary source is in the fortune of other facilities in building body
Row, the walking about of personnel, the large-scale sports facility on building periphery and motor vehicles etc., its route of transmission are rigid solid material.Sound
The direct sources of wave interference are the noises in air, including operation facility noise, the speech of personnel and the off-premises station inside and outside building are moved
The noise of vehicle, its route of transmission is air.The direct sources of electromagnetic interference are the electromagnetic radiation in environment, including inside and outside stair
High pressure computer room, all kinds of transformers, power circuit and other electric equipments, its route of transmission.Need to take certain measure
Isolated, to reduce these influences of the interference to acoustic sensor self noise measurement result.Anti-interference screening arrangement is acoustics
The primary condition that sensor self noise measuring system can effectively be run.The country does not possess oneself of miniature acoustic sensor still at present
Noise testing condition.
The content of the invention
It is an object of the invention to overcome the shortcomings of that prior art is present, and provide a kind of for acoustic sensor self noise
The interference shielding device of measurement, good environmental condition is provided for acoustic sensor self noise measurement.
The purpose of the present invention is completed by following technical solution.It is this to be used for what acoustic sensor self noise was measured
Interference shielding device, comprising matrix platform, metal cabinet, vacuum cylinder and pumped vacuum systems, metal cabinet is placed on matrix platform
Top, vacuum cylinder is placed inside metal cabinet, and tested acoustic sensor is arranged on inside vacuum cylinder, is suspended on vacuum cylinder and is covered
Lower end, tested acoustic sensor is connected by electric connector and cable with Noise Acquisition system；Pumped vacuum systems is located at gold
Belong to the outside of casing, connected between pumped vacuum systems and vacuum cylinder by flexible tracheae, flexible tracheae passes through the case of metal cabinet
It is high vacuum state in wall, vacuum cylinder.
The installation weight that described matrix platform and metal cabinet are constituted is at least above 1 ton, own resonance frequency ＜ 2Hz；
Matrix platform is in integrally bar shape, altogether comprising the part of upper, middle and lower three, and two parts are the base layer of metal material, center section up and down
For flexible Damping material layer.
Described metal cabinet has a sound absorption function, and metal cabinet is in integrally bar shape, its lower surface and matrix platform
Upper surface constitutes effective plane contact, and the tank wall of metal cabinet has certain thickness, and the metal outer of tank wall is using highdensity
Metal material is coated, and as anti-sound layer, can effectively reflect the sound wave of outside；The internal layer of tank wall and tank wall intermediate layer are sound absorption
Layer, filled with a variety of sound-absorbing materials, can effectively absorb the sound wave transmitted by tank wall outer layer into；It is provided with metal cabinet logical
Hole, for cable and flexible tracheae to be introduced in metal cabinet.
The metal outer and vacuum cylinder of described metal cabinet all use metal material, and carry out being electrically connected realization respectively
Equipotential, and gap is coated using wire netting, realize double-deck electromagnetic shielding.
Described flexible tracheae and the junction of vacuum cylinder are provided with transfer tube, are provided with the connecting line vacuumized true
Empty table and vacuum valve.
Beneficial effects of the present invention are：A variety of interference that screening arrangement in the present invention is just used in Isolated Shield environment,
There is significant shield effectiveness to vibration interference, sound wave interference and Electromagnetic Interference, can be effective for acoustic sensor self noise
Measurement.
Brief description of the drawings
Fig. 1 is structural representation of the invention.
Mark 1 is matrix platform in figure；Mark 2 is the flexible Damping material layer for being seated in matrix platform interior；Mark 3 is
Metal cabinet；Mark 4 is the metal outer of metal cabinet；Mark 5 is the tank wall intermediate layer of metal cabinet；Mark 6 is vacuum cylinder,
Mark 7 is tested acoustic sensor；Mark 8 is electric connector；Mark 9 be cable, for connect tested acoustic sensor with
Noise Acquisition system；Mark 10 is the through hole on the tank wall of metal cabinet, the introducing for cable 9 and tracheae 11；Mark 11 is
Flexible tracheae for connecting vacuum cylinder and pumped vacuum systems；Mark 12 is the switching for connecting vacuum cylinder and flexible tracheae
Pipe；Mark 13 is vacuum meter, for monitoring the vacuum in vacuum cylinder；Mark 14 is vacuum valve.
Embodiment
Detailed introduction is done to the present invention below in conjunction with accompanying drawing：
As shown in figure 1, this interference shielding device measured for acoustic sensor self noise, includes matrix platform 1, gold
Belong to casing 3, vacuum cylinder 6 and pumped vacuum systems, be provided simultaneously with the function of vibration shielding, sound wave shielding and electromagnetic shielding.Matrix is put down
Platform 1 is placed on ground, and metal cabinet 3 is placed on the top of matrix platform 1, and vacuum cylinder 6 is placed inside metal cabinet 3, tested sound
Learn sensor 7 to be arranged on inside vacuum cylinder 6, be suspended on the lower end covered on vacuum cylinder 6, tested acoustic sensor 7 is by being electrically connected
Connect device 8 and cable 9 is connected with Noise Acquisition system；Pumped vacuum systems is located at the outside of metal cabinet 3, pumped vacuum systems and vacuum
Connected between cylinder 6 by flexible tracheae 11, it is high vacuum shape that flexible tracheae 11, which is passed through in the tank wall of metal cabinet 3, vacuum cylinder 6,
State.The junction of described flexible tracheae 11 and vacuum cylinder 6 is provided with transfer tube 12, is provided with the connecting line vacuumized true
Empty table 13 and vacuum valve 14.The main object of the present invention is to reduce measuring environment interference to measure the self noise of acoustic sensor
As a result influence, realizes vibration shielding, sound wave shielding, electromagnetic interference shield function, obtains a good measuring environment condition.
On the influential environmental disturbances of acoustic sensor self noise measurement mainly comprising vibration interference, sound wave interference and electromagnetism
Wave interference, therefore anti-interference shielding design is carried out in terms of three from this respectively, realize that the effective ways of shielding interference are mainly change
The approach of interferencing propagation.
The measure of vibration shielding is while improves device by improving weight and the flexible damping material two ways of addition
Vibrate shield effectiveness.Concrete measure one is the weight for improving matrix platform 1 and metal cabinet 3 so that 1 ton of device gross weight ＞, from
Body resonant frequency ＜ 2Hz.Concrete measure two is to use the platform with damping design as the matrix of whole screening arrangement, matrix
The weight of platform 1 is very big, and so its own natural resonance frequency is just very low, and the interference effect of dither is just small.Because vibration
Propagating needs certain rigid media, and Vibration propagation can be effectively blocked using flexible damping design.Overall matrix platform 1 is in cylinder
Shape, such as cylinder or cuboid, upper and lower surface are smooth, and positioned at horizontal direction, are suitable for putting for metal cabinet 3
Put.Matrix platform 1 includes the part of upper, middle and lower three altogether, and two parts are the base layer of metal material up and down, and center section hinders to be flexible
Damping material layer 2.Matrix platform can directly be placed or placed on the ground by support feet.
The measure of sound wave shielding is while improves using changing Acoustic Wave Propagation impedance and removing propagation medium two ways
Sound wave shield effectiveness, it is that removing propagation medium is based on sound wave reflecting material, absorbing material realization to change Acoustic Wave Propagation impedance
Realized based on vacuumize process.One of concrete measure is to use the metal cabinet 3 with sound absorption function.Metal cabinet 3 is overall
In bar shape, such as cylinder or cuboid, lower surface is usually smooth, can effectively be connect with the upper surface of matrix platform
Touch.The tank wall of metal cabinet 3 has certain thickness, and the metal outer 4 of tank wall is coated using highdensity metal material, is used as anti-sound
Layer, can effectively reflect the sound wave of outside.The internal layer of tank wall and tank wall intermediate layer 5 are absorbent treatment, filled with a variety of sound-absorbing materials,
The sound wave transmitted by tank wall outer layer into can effectively be absorbed.There is opened hole 10 in the side wall of metal cabinet or top, mainly
It is soft between connection cable 9, vacuum cylinder and the pumped vacuum systems between acoustic sensor and self noise measuring system for being tested
Property tracheae 11 and other cables introduce in quiet room, perforate is sealed using the encapsulant of good seal performance, with guarantor
The acoustically effective of card wall will not wait until reason and reduce because of hole.Another concrete measure of sound wave shielding is so that vacuum
It is high vacuum state in cylinder, is further to reach that sound wave is isolated because aerial propagate of sound wave is needed using air as medium
Purpose, in vacuum cylinder air carry out vacuumize process with regard to effect can be reached.Vacuum cylinder is cylinder, for example cylinder or
Cuboid, can bear stronger external pressure.Vacuum cylinder includes upper lid, barrel and the part of lower cover three, and all needing to meet certain thickness will
Ask, and using being tightly connected between three.Lid is equipped with electric connector, cable, transfer tube and flexible tracheae on vacuum cylinder.Electrical connection
Device must be airproof.Connection between being covered on electric connector and vacuum cylinder uses gas-tight design, and cable and electric connector it
Between connection without gas-tight design.Transfer tube is same with the connection on vacuum cylinder between lid, flexible tracheae and transfer tube to use gas
Close design.Electric connector and cable are used to be tested acoustic sensor and the connection of Noise Acquisition system.Transfer tube and flexible tracheae
For the connection between vacuum cylinder and pumped vacuum systems.
What is be electromagnetically shielded takes two measures altogether.Concrete measure one for metal cabinet 3 metal outer 4 and vacuum cylinder 6 all
It is electrically connected using metal material, and respectively.Wherein cabinet exterior uses ordinary steel material, and vacuum cylinder uses stainless steel
Matter, and vacuum drum outer wall copper plating treatment.Apertured place is using the flexible material of electromagnetic shielding on all outer walls of metal cabinet
Material is coated so that metal outer one complete metallic shield cavity of formation of whole casing.And to the barrel of vacuum cylinder
Using same processing, then positioned at the acoustic sensor inside vacuum cylinder just have the protection of double-deck electromagnetic shielding cavity every
From can keep out the interference of power frequency electromagnetic field, can also shield high frequency electromagnetic radiation.
Embodiment：
Matrix platform 1 is placed on the ground first, every square metre of ground ability >=2 ton.The implementation case of the present invention
Example matrix platform is in integrally that the flexible damping material 2 in cuboid, matrix platform uses multilayer solid composite rubber, is added in proportion
The materials such as fiber, graphite have been added to synthesize.The lower surface of platform 1 is placed on the ground using four supporting legs, adjustment matrix platform 1
Supporting leg, make its upper surface be in horizontality.The length, width and height size of case study on implementation matrix platform 1 of the present invention is respectively
1.6 meters, 1.2 meters and 0.6 meter, it is about 2Hz~3Hz to obtain its intrinsic frequency, and the μ of Oscillation Amplitude ＜ 1 of the upper surface of matrix platform 1
M, platform gross weight 600kg.
The lower surface of the case study on implementation metal cabinet 3 of the present invention is placed on the upper surface of matrix platform 1, and metal cabinet 3 is whole
Body is in cube, and length, width and height size is respectively 1.6 meters, 1.2 meters and 1.2 meters.The tank wall intermediate layer 5 of metal cabinet 3 uses air
Deadener constitutes the light structure of composite bed, and thickness is 200mm.One side of metal cabinet 3 with one soundproof door, width and
Highly be respectively 800mm and 800 ㎜, soundproof door uses steel sound-proof door, single fan rotary type, sound insulation door frame with wall connecting
The effect of sealing shock insulation is played, prevents sound from passing through the weak link string such as hole of doorframe and wall using shock absorber processing in place
Enter interior.Carried out using shock absorber after impedance bundary, effectively suppress door leaf and receive caused vibration during sound wave incident, hence it is evident that improve
Sound insulation room effect, significantly increases its frequency range that insulates against sound.Another side cornice of metal cabinet 3 has through hole 10, cable 9
With flexible tracheae 11 therethrough, sound absorbent rubber is filled with hole.Illumination electricity-saving lamp is installed, to ensure room in metal cabinet
Intraoral illumination.The metal outer 4 of metal cabinet 3 carries out totally-enclosed electric connection using electromagnetic shield rubber material, and all pipelines are all
Wrapped up using electromagnetic shielding net, realize function of shielding.The case study on implementation metal cabinet gross weight of the present invention is 600kg.
The case study on implementation vacuum cylinder 6 of the present invention is cylinder, overall diameter 300mm, height 300mm, wall thickness 2cm.Vacuum cylinder 6
It is placed on by the soundproof door of metal cabinet 3 on the bottom surface of box house, O-ring seal is used between its upper and lower covers and bucket wall
Carry out gas seal member.The electric connector 8 that the upper lid of vacuum cylinder 6 is installed is connected from small circular two core that Subconn companies of the U.S. produce
Device is connect, transfer tube 12 and flexible tracheae 11 are from the big Lip river gram product of German generation.In order to obtain vacuum, ensure flexible tracheae first
Valve 14 is in open mode, and operation pumped vacuum systems 20 minutes turns off valve 14, finally closes vavuum pump, observes vacuum
The vacuum degree of table 13, numerical value is good and stablizes constant then satisfaction requirement.It is observed that the vacuum cylinder 3, which can be stablized, keeps ＜ 1kPa
Vacuum.
By test, case study on implementation of the invention possesses good shield effectiveness, device low-frequency resonant ＜ 2Hz, ground with
Sound wave shield effectiveness ＞ outside vibration shield effectiveness ＞ 20dB between in vacuum cylinder, metal cabinet between metal drum inside
40dB, effectiveness ＞ 60dB.
It is understood that it will be understood by those skilled in the art that being subject to technical scheme and inventive concept
It should all belong to the protection domain of appended claims of the invention with replacing or changing.
Claims (5)
1. a kind of interference shielding device measured for acoustic sensor self noise, it is characterised in that：Comprising matrix platform (1),
Metal cabinet (3), vacuum cylinder (6) and pumped vacuum systems, metal cabinet (3) are placed on above matrix platform (1), vacuum cylinder (6)
Place metal cabinet (3) internal, tested acoustic sensor (7) is arranged on vacuum cylinder (6) inside, is suspended on vacuum cylinder (6)
The lower end of lid, tested acoustic sensor (7) is connected by electric connector (8) and cable (9) with Noise Acquisition system；Vacuumize
System is located at the outside of metal cabinet (3), is connected between pumped vacuum systems and vacuum cylinder (6) by flexible tracheae (11), flexible
It is high vacuum state that tracheae (11), which is passed through in the tank wall of metal cabinet (3), vacuum cylinder (6),.
2. the interference shielding device according to claim 1 measured for acoustic sensor self noise, it is characterised in that：Institute
The installation weight that the matrix platform (1) and metal cabinet (3) stated are constituted is at least above 1 ton, own resonance frequency ＜ 2Hz；Matrix
Platform (1) is in integrally bar shape, altogether comprising the part of upper, middle and lower three, and two parts are the base layer of metal material, center section up and down
For flexible Damping material layer (2).
3. the interference shielding device according to claim 1 measured for acoustic sensor self noise, it is characterised in that：Institute
The metal cabinet (3) stated has a sound absorption function, and metal cabinet (3) is in integrally bar shape, its lower surface and matrix platform (1) it is upper
Surface constitutes effective plane contact, and the tank wall of metal cabinet (3) has certain thickness, and the metal outer (4) of tank wall is using highly dense
The metal material cladding of degree, as anti-sound layer, can effectively reflect the sound wave of outside；The internal layer of tank wall and tank wall intermediate layer (5)
For absorbent treatment, filled with a variety of sound-absorbing materials, the sound wave transmitted by tank wall outer layer into can be effectively absorbed；Metal cabinet (3)
On be provided with through hole (10), for cable (9) and flexible tracheae (11) to be introduced in metal cabinet (3).
4. the interference shielding device according to claim 3 measured for acoustic sensor self noise, it is characterised in that：Institute
The metal outer (4) and vacuum cylinder (6) for the metal cabinet (3) stated all use metal material, and carry out being electrically connected realization respectively
Equipotential, and gap is coated using wire netting, realize double-deck electromagnetic shielding.
5. the interference shielding device according to claim 1 measured for acoustic sensor self noise, it is characterised in that：Institute
The junction of the flexible tracheae (11) stated and vacuum cylinder (6) is provided with transfer tube (12), is provided with the connecting line vacuumized
Vacuum meter (13) and vacuum valve (14).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710260829.9A CN107167231A (en) | 2017-04-20 | 2017-04-20 | A kind of interference shielding device measured for acoustic sensor self noise |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710260829.9A CN107167231A (en) | 2017-04-20 | 2017-04-20 | A kind of interference shielding device measured for acoustic sensor self noise |
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| CN107167231A true CN107167231A (en) | 2017-09-15 |
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| CN201710260829.9A Pending CN107167231A (en) | 2017-04-20 | 2017-04-20 | A kind of interference shielding device measured for acoustic sensor self noise |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108490844A (en) * | 2018-05-11 | 2018-09-04 | 湖南菲尔姆真空设备有限公司 | A kind of high-accuracy and constant pressure closed-loop control instrument |
| CN114089237A (en) * | 2021-09-26 | 2022-02-25 | 湖北省地震局(中国地震局地震研究所) | Isolation structure of fluxgate sensor |
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| US20160376740A1 (en) * | 2013-02-18 | 2016-12-29 | Owens Corning Intellectual Capital, Llc | Acoustically insulated machine |
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Patent Citations (4)
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| CN101813513A (en) * | 2010-01-07 | 2010-08-25 | 中国科学院半导体研究所 | Hydrophone testing device |
| US20160376740A1 (en) * | 2013-02-18 | 2016-12-29 | Owens Corning Intellectual Capital, Llc | Acoustically insulated machine |
| CN203635464U (en) * | 2013-12-04 | 2014-06-11 | 北京国奥时代新能源技术发展有限公司 | High-power ultrasonic transducer blimp |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108490844A (en) * | 2018-05-11 | 2018-09-04 | 湖南菲尔姆真空设备有限公司 | A kind of high-accuracy and constant pressure closed-loop control instrument |
| CN114089237A (en) * | 2021-09-26 | 2022-02-25 | 湖北省地震局(中国地震局地震研究所) | Isolation structure of fluxgate sensor |
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Application publication date: 20170915 |