CN105916093B - A kind of surface microphone calibrator - Google Patents
A kind of surface microphone calibrator Download PDFInfo
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- CN105916093B CN105916093B CN201610450879.9A CN201610450879A CN105916093B CN 105916093 B CN105916093 B CN 105916093B CN 201610450879 A CN201610450879 A CN 201610450879A CN 105916093 B CN105916093 B CN 105916093B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R29/00—Monitoring arrangements; Testing arrangements
- H04R29/004—Monitoring arrangements; Testing arrangements for microphones
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- General Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
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- Acoustics & Sound (AREA)
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- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
Abstract
A kind of surface microphone calibrator, and in particular to a kind of calibrating installation specially designed for this special type microphone of surface microphone belongs to microphone calibration field.The device non-standard platypelloid type structure special for surface microphone, devise the asymmetric short coupling cavity configuration of new platypelloid type, flat major diameter gland structure, the surface microphone upper shield structure independently simplified, ensure that surface microphone and standard microphone receive sound field consistency and leakproofness and the device for different size surfaces microphone versatility.Compared with the general calibrating installation of existing conventional microphone, which is specifically applied to surface microphone, and the calibration accuracy and device versatility of surface microphone can be improved.
Description
Technical field
The present invention relates to a kind of microphone calibrators, and in particular to one kind is that microphone this special type microphone in surface is special
The calibrating installation of door design belongs to microphone calibration field.
Background technique
Currently, the collimation techniques such as coupler reciprocal method or comparison method for conventional microphone are ripe day by day, due to normal
It advises microphone size and has standard specification (1,1/2,1/4,1/8 inch etc.), therefore its calibrating installation can be general, calibration is accurate
It spends also guaranteed.
However surface microphone belongs to special type microphone, it is pancake structure that shape is more special with structure, from
Body front end can not probe into conventional slender type coupler and be symmetrically installed with standard microphone without cavity.In addition, conventional elongated circle
The problems such as small-sized gland used in column type microphone also can not be general with pancake structure, has unbalance stress exists.Finally,
Market upper surface microphone finished product there is no unified specification at present, diameter between 40mm-60mm, thickness 2.8mm-9mm it
Between, there is larger difference from right cylindrical to spherical arc shape in shape, it is difficult to design completely general calibrating installation.
In view of the above problems, solution is producer or calibration personnel for the special switching of different product manufacture at present
It is adapted to tooling, surface microphone is transferred on conventional coupler and is calibrated.From acoustic theory angle, there are two for this method
Problem: variable diameter at switching tooling generally existing two first, one is in the diameter change to tooling of surface microphone sound wave region of acceptance
Diameter, two change to coupler internal diameter for tooling internal diameter, and variable diameter can cause sound field centainly to distort at two；Secondly switching tooling length
Generally it is not less than 10mm, too long switching inner cavity keeps sound field space in coupler seriously asymmetric, in addition can also aggravate high frequency sound
Field distortion.The above two o'clock can carry out larger impact to surface microphone calibration tape, reduce calibration accuracy.From Practical Project and economy
Angle, this method is every calibrate a kind of surface microphone just must the special tooling of first design and fabrication, add additional calibration
Period and cost.
Therefore, the calibrating installation needs of surface microphone are specially designed, and are avoided the switching link in coupler, are made table
Face microphone and standard microphone direct-coupling, inevitable external structure switching, also make every effort to simplified as far as possible, to improve it
Calibration accuracy and versatility.
Patent disclosed in 2010-11-24: CN101895809A, topic: " a kind of microphone calibrator and its calibration side
Method ", inventor: Wang Li；Wang Tongqing.A kind of microphone calibrator of the disclosure of the invention and its calibration method, including from front to back
Sequentially connected silencer, microphone construction section to be calibrated, standard microphone construction section and sound source, and pacify in microphone to be calibrated
It is provided with microphone mounting hole to be calibrated in dress section, for installing microphone to be calibrated；Standard is provided on standard microphone construction section
Microphone mounting hole, for installing standard microphone.Two different standard microphone mounting holes are selected according to different frequencies
Two standard microphones are installed, silencer complex reflection coefficient r is measured to obtain, the Complex sensitivity for then obtaining microphone to be calibrated is bent
Line；The sound wave for issuing different frequency respectively by sound source obtains the Complex sensitivity curve of microphone to be calibrated, to reach to school
The purpose of quasi- microphone calibration.Calibration while a large amount of microphones may be implemented in the invention, saves prover time, and can be with
Phase alignment is carried out to microphone.
Patent disclosed in 2012-07-25: CN102611982A, topic: " microphone calibration fixture ", inventor: what
It hears；It is all remote next；Jia Shushi.A kind of disclosure of the invention microphone calibration fixture, including be fixed on pistonphone and with it is closed
The hollow support of cavity wall connection is socketed in support for installing the hollow housing of microphone to be calibrated, and by housing
The retaining mechanism being fixed to each other with support and microphone；Microphone to be calibrated is inserted into jacket internal, housing include with it is transaudient
The sleeve part of device clearance fit and the tight lock part that microphone is fixed with retaining mechanism cooperation, the acoustic pressure compensation hole of microphone are located at
In the region of sleeve part covering；The first sealing ring, the sleeve part of support and housing are equipped between the sleeve part and microphone of housing
Between be equipped with the second sealing ring, between support and closed cavity wall be equipped with third sealing ring.The invention simple, microphone with structure
Easy for assemble or unload, the advantages of microphone clamping is solid and reliable, good airproof performance.
Patent disclosed in 2014-03-05: CN203463653U, a kind of topic: " two for the calibration of high sound pressure microphone
Section sealing machine structure ", inventor: Yan Lei；Yang Xiaowei；Zhu Gang；Liu Xin；；Miao Yin night；Li Qiang；Pei Yapeng；Zhang great You；Salty treasured
Gold.The utility model provides a kind of two sections of sealing machine structures for the calibration of high sound pressure microphone.Wherein, special-shaped O-ring is embedding
Entering to be threaded into the groove of circle, after microphone preamplifier is connect with microphone, insertion is threaded into the mounting hole of circle,
Make to be threaded into the special-shaped O-ring between circle and microphone to compress；Standard O-ring and the embedment microphone installation of wedge-type seal collar
In the mounting hole of wall；Microphone is inserted in microphone protection grid shell, and microphone protects grid shell Probe microphone mounting wall
It in mounting hole, tightens and is threaded into circle, thrust is tightened by screw thread, microphone mounting wall and microphone is made to protect grid shell
Between compressed by standard O-ring and wedge-type seal collar.The utility model structure can fix microphone position, microphone axis
Line is not deviated with mounting hole axis, and double-layer sealing structure reduces pressure leakages rate.
The present invention and existing patent the difference is that: the present invention is designed for surface microphone, and unconventional biography
Sound device.The pancake structure that coupler, gland and upper shield are directed to surface microphone has carried out special designing, and wherein platypelloid type is non-
Symmetrical short coupler is more bonded with surface microphone, enables surface microphone and standard microphone direct-coupling, and practical coupling
It is symmetry equivalent to close chamber volume, to ensure that the consistency of sound field；And large scale gland can be by surface microphone completely densified
In upper shield, the leakproofness of sound field ensure that；Finally, independently simplified upper shield inexpensive can customize simultaneously quick-replaceable, meet
The installation of different size surface microphone products reduces calibration cycle and cost to greatest extent, improves device versatility.This hair
Bright is the dedicated calibrating installation of surface microphone, and the calibration accuracy and device versatility of surface microphone can be improved.
Summary of the invention
The purpose of the present invention is to solve the dedicated calibrating installations and surface microphone that lack surface microphone on the market
The lower problem of calibration accuracy, and a kind of surface microphone calibrator has been invented, to improve the school of surface microphone
Quasi- accuracy and device versatility.
The purpose of the present invention is what is be achieved through the following technical solutions.
A kind of surface microphone calibrator includes base portion, coupling cavity segment and retained part.Base portion includes
Pedestal, standard microphone upper shield, standard microphone, foot pad, play the role of support device；Coupling cavity segment includes lower coupling
Chamber, upper coupler, coupler liner, dynamic iron sound source, seal O-ring, are apparatus main body, are calibrated using its inner cavity；Clamping
Part include loop, major diameter gland, surface microphone upper shield, connection bolt, tension spring, to be calibrated surface microphone into
Row is clamped and is fixed.Wherein coupler is platypelloid type, unsymmetric structure and the design of short inner cavity；Major diameter gland, which uses, is not less than table
The flat gland of face microphone diameter；Microphone upper shield design in surface is independent to be simplified, and upper layer and lower layer are different inner diameters, are socketed respectively
Upper coupler and surface microphone, and the two is connected, simple structure, processing and replacement rapid and convenient and cost is extremely low, maximum
Limit ensure that device versatility.
Before calibration, first the pedestal with foot pad is placed in the horizontal plane；Loop covers the blending bolt on pedestal and fastens,
It is connected by tension spring with major diameter gland, loop can be moved up and down in datum axle under bolt relaxation state, be drawn to adjust
The tensile force of power spring；Standard microphone is inserted in standard microphone upper shield, is pressed into base intracavity top together；It is transaudient with standard
Device is fulcrum, is inserted in the coupling cavity of lower coupler and upper coupler composition.
When calibration, first the under shed of surface microphone upper shield is covered on upper coupler, then surface will be calibrated
Microphone is put into the upper opening of surface microphone upper shield, and major diameter gland is finally pressed in the upper table for being calibrated surface microphone
On face.Since surface microphone upper shield under shed internal diameter is identical as upper coupler outer diameter, upper opening internal diameter and it is calibrated surface
Microphone outer diameter is identical, in conjunction with the pressure that tension spring tensile force is converted to, is calibrated surface microphone and is just socketed and is compressed
In the plane of upper coupler, cooperation seal O-ring reaches fixed and sealing effect.
For the surface microphone of different model, the upper opening internal diameter R of surface microphone upper shield can be changed according to its size
With thickness H, it is customized.Due to its simple structure, easy making process is suitble to fast custom and assembly, to subtract to the greatest extent
Major's paracycle and cost, and improve the versatility of device.
Beneficial effect
1, the invention devises a kind of asymmetric short coupler of platypelloid type.It, can not due to the flat structure of surface microphone
Probe into conventional elongated lumens with standard microphone direct-coupling, it is therefore necessary to transfer, variable diameter position among these can make
Sound field is distorted；Furthermore in view of microphone itself front end in surface is without cavity, if coupler still follows conventional symmetrical junction
Structure design, then the practical coupler volume of surface microphone can be less than the practical coupler volume of standard microphone, the difference of volume
Itself cavity as between standard microphone diaphragm and grid cover, and the practical coupler volume of the two is different, will cause coupling
Also there is difference in intracavitary sound field, i.e. the sound field that receives of surface microphone and standard microphone is not consistent, to reduce calibration
Accuracy.Therefore the present invention has redesigned coupler, and flat structure design pastes coupler with surface microphone in shape
It closes, so that surface microphone is directly coupled with standard microphone opposite direction in conjunction with the short cavity design of of length no more than 3mm, avoid
Inner cavity switching；The ante-chamber that the design of asymmetrical cavity volume joined microphone itself calculates, and guarantees the practical coupling of surface microphone
It closes chamber volume and is equal to standard microphone coupler volume plus its own ante-chamber volume, and then the sound field for receiving the two is basic
Unanimously, achieve the purpose that improve calibration accuracy.
2, the invention devises a kind of new surface microphone installation gland.Original small-sized convex surface gland is suitable for cut
The lesser cylindrical type routine microphone of area is together in upper shield indentation coupler.But for surface microphone, shaped flat and cut
Area is larger, and no image of Buddha routine microphone probes into coupler equally to guarantee leakproofness, can only be pressed in coupler upper surface, if
Still continue to use original small-sized convex gland mode it will cause installation unbalance stress, cannot be by surface microphone completely densified in coupling
It closes on chamber, sound field is caused to leak between uncompacted plane gap.Therefore the present invention devises major diameter gland, that is, uses
Flat gland not less than surface microphone diameter is installed, and complete compacting surface microphone makes itself and table on coupler
The reserved seamless uniform contact of groove in face, ensure that the leakproofness of sound field.
3, the invention devises a kind of new surface microphone installation upper shield.Since conventional microphone size has standard rule
Lattice (1,1/2,1/4,1/8 inch etc.), therefore original calibrating installation and switching adaptive device can be general.But surface microphone
It there is no unified specification at present, diameter is between 40mm-60mm, and thickness is between 2.8mm-9mm, and shape is from right cylindrical to ball
There is larger difference in arc, can not omit for the switching fixture of external structure, also cannot achieve absolute general, Zhi Neng
Under the premise of guarantee does not influence inner cavity, will retained part relevant to external dimensions it is independent and simplify, convenient for according to production
Product size fast custom is simultaneously replaced, and calibration cycle and cost are reduced, and improves device versatility.Therefore the present invention devises independent letter
The surface microphone upper shield of change, upper layer and lower layer are different inner diameters, are socketed coupler epicoele and surface microphone respectively, and by the two
Connection, simple structure, processing with replace rapid and convenient and cost it is extremely low, ensure that device versatility to greatest extent.And the upper shield
The switching of external structure is only related to, is not related to inner cavity switching, therefore have no effect on sound field in coupler.
In general, the advantage of the invention is that considering surface microphone special structure and shape, to coupler, pressure
Lid re-starts design with upper shield, ensure that surface microphone and standard microphone receive the consistency and leakproofness of sound field, with
And the versatility to different size surfaces microphone.Compared with the general calibrating installation of existing conventional microphone, the calibrating installation
The calibration accuracy and device versatility of surface microphone can be improved in more applicable and surface microphone.
Detailed description of the invention
Fig. 1 is general structure schematic diagram of the invention；
Fig. 2 is enlarged diagram in coupling cavity of the invention；
Fig. 3 is surface microphone upper shield schematic diagram of the invention；
Appended drawing reference: coupler, the upper coupler of 5-, 6- coupling under 1- pedestal, 2- loop, 3- standard microphone upper shield, 4-
Intracavitary lining, 7- major diameter gland, the surface 8- microphone upper shield, 9- connection bolt, the surface 10- microphone, 11- move iron sound source, 12-
Seal O-ring, 13- tension spring, 14-1/2 inch standard microphone, 15- foot pad.
Specific embodiment
With reference to the accompanying drawing with embodiment, the present invention will be described in detail.
A kind of surface microphone calibrator, overall structure is as shown in Figure 1, calibration object is disposable type surface microphone
10, reference object is 1/2 inch standard microphone 14.
Device noumenon includes three parts:
One, base portion, comprising: pedestal 1, standard microphone upper shield 3, standard microphone 14, foot pad 15 play support dress
The effect set；
Two, couple cavity segment, including lower coupler 4, upper coupler 5, coupler liner 6, dynamic iron sound source 11, sealing are O-shaped
Circle 12 is apparatus main body, is calibrated using its inner cavity；
Three, retained part, including loop 2, major diameter gland 7, surface microphone upper shield 8, connection bolt 9, tension spring
13, it is clamped and is fixed to surface microphone 10 is calibrated.
Before calibration, first do following assembly: the pedestal 1 with foot pad 15 is placed in the horizontal plane；2 sets of loop in pedestal 1
Upper blending bolt fastening, is connected by tension spring 13 with major diameter gland 7, loop 2 can be in 1 axis of pedestal under bolt relaxation state
It moves up and down, to adjust the tensile force of tension spring 13；Standard microphone 14 is inserted in standard microphone upper shield 3, is pressed together
Enter 1 inner cavity top of pedestal；It is fulcrum with standard microphone 14, is inserted in the coupling cavity of lower coupler 4 with upper coupler 5 composition
In.
When calibration, first the under shed of surface microphone upper shield 8 is covered on upper coupler 5, then table will be calibrated
Face microphone 10 is put into the upper opening of surface microphone upper shield 8, is finally pressed in major diameter gland 7 and is calibrated surface microphone
On 10 upper surface.Since microphone upper shield 8 under shed internal diameter in surface is identical as upper 5 outer diameter of coupler, upper opening internal diameter with
It is calibrated that microphone 10 outer diameter in surface is identical, in conjunction with the pressure that 13 tensile force of tension spring is converted to, calibration surface microphone 10
Just it is socketed and is pressed in the plane of upper coupler 5, cooperation seal O-ring 12 reaches fixed and sealing effect.
It illustrates, as shown in Fig. 2, by lower coupler 4, coupler liner 6, seal O-ring 12, to be calibrated surface transaudient
Device 10, standard microphone 14 define closed interior coupling cavity, and cavity length is no more than 3mm, that is, is calibrated surface microphone 10
It is coupled with the directly opposite direction of standard microphone 14, avoiding intracavitary switching influences.And it according to the asymmetrical design precalculated, moves
The assembly axis of iron sound source 11 moves down, and the practical coupler volume a for being calibrated surface microphone 10 is made to be equal to standard microphone 14
Coupler volume b ensure that plus cavity volume c before standard microphone 14 itself and be calibrated surface microphone and standard microphone
Practical coupler volume it is equal, and then both make the sound field received almost the same, reach that improve the calibration of surface microphone quasi-
The purpose of exactness.
As above all after the assembly is completed, control dynamic iron sound source 11 according to vertification regulation sounding, standard of comparison microphone 14 with
It is calibrated the response of surface microphone 10, and then is calibrated to surface microphone 10 is calibrated.
For the product of different model, the upper opening internal diameter R and thickness of surface microphone upper shield 8 can be changed according to its size
H is customized, as shown in Figure 3.Due to its simple structure, easy making process is suitble to fast custom and assembly, thus utmostly
Reduction calibration cycle and cost, and improve the versatility of device.
Claims (2)
1. a kind of surface microphone calibrator, which is characterized in that include base portion, coupling cavity segment and retained part；Its
Middle base portion includes pedestal, standard microphone upper shield, standard microphone, foot pad, plays the role of support device；Couple cavity portion
Be apparatus main body point including lower coupler, upper coupler, coupler liner, dynamic iron sound source, seal O-ring, using its inner cavity into
Row calibration；Retained part includes loop, major diameter gland, surface microphone upper shield, connection bolt, tension spring, to being calibrated
Surface microphone is clamped and is fixed；
The coupler is platypelloid type, unsymmetric structure and the design of short inner cavity；The major diameter gland, which uses, is not less than table
The flat gland of face microphone diameter；The surface microphone upper shield design is independent to be simplified, and upper layer and lower layer are different inner diameters, point
Coupler and surface microphone Tao not be connected, and the two is connected；In the unsymmetric structure, the assembly axis of iron sound source is moved
It moves down, so that the practical coupler volume a for being calibrated surface microphone is equal to standard microphone coupler volume b transaudient plus standard
Cavity volume c before device itself；
Connection relationship are as follows: before calibration, first place the pedestal with foot pad in the horizontal plane；Loop covers on pedestal and uses spiral shell
Bolt fastening, is connected by tension spring with major diameter gland, loop is moved up and down in datum axle under bolt relaxation state, to adjust
Save the tensile force of tension spring；Standard microphone is inserted in standard microphone upper shield, is pressed into base intracavity top together；With standard
Microphone is fulcrum, is inserted in the coupling cavity of lower coupler and upper coupler composition；When calibration, first by surface microphone
The under shed of upper shield covers on upper coupler, then the upper opening that will be calibrated surface microphone and be put into surface microphone upper shield
It is interior, finally major diameter gland is pressed on the upper surface for being calibrated surface microphone；Due to surface microphone upper shield under shed
Internal diameter is identical as upper coupler outer diameter, and upper opening internal diameter is identical as surface microphone outer diameter is calibrated, and is tensioned in conjunction with tension spring
The pressure that power is converted to is calibrated surface microphone and is just socketed and is pressed in the plane of upper coupler, cooperates seal O-ring
Reach fixed and sealing effect.
2. a kind of surface microphone calibrator as described in claim 1, which is characterized in that the surface microphone upper shield
Upper opening internal diameter R and thickness H according to the size of the surface microphone of different model change, be customized.
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| CN108007561B (en) * | 2017-12-12 | 2019-11-12 | 中国航空工业集团公司北京长城计量测试技术研究所 | Probe microphone high temperature calibrating installation |
| CN110505562B (en) * | 2018-05-17 | 2021-02-09 | 北京航天计量测试技术研究所 | Planar microphone mounting structure for free field calibration |
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| CN101895809A (en) * | 2010-07-01 | 2010-11-24 | 北京航空航天大学 | Microphone calibrator and calibration method thereof |
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