CN106507262A - A kind of diaphragm of loudspeaker tester with controlled excitation source - Google Patents
A kind of diaphragm of loudspeaker tester with controlled excitation source Download PDFInfo
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- CN106507262A CN106507262A CN201611222467.6A CN201611222467A CN106507262A CN 106507262 A CN106507262 A CN 106507262A CN 201611222467 A CN201611222467 A CN 201611222467A CN 106507262 A CN106507262 A CN 106507262A
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- test
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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
- H04R29/001—Monitoring arrangements; Testing arrangements for loudspeakers
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- General Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
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Abstract
The present invention proposes a kind of diaphragm of loudspeaker tester with controlled excitation source, including platform to be measured, controlled excitation source, laser displacement sensor, control device;Vibrating diaphragm to be measured is fixed on platform to be measured, and laser displacement sensor is fixed on platform to be measured;Vibrating diaphragm to be measured is co-axially located on platform to be measured with laser displacement sensor;Control signal is input into controlled excitation source by control device, and controlled excitation source produces pumping signal according to the control signal;Pumping signal excitation of the vibrating diaphragm to be measured produced by controlled excitation source produces vibration;Vibration information during laser displacement sensor detection diaphragm oscillations.Controlled excitation source of the present invention can preferably excite diaphragm oscillations to be measured, obtain vibrating diaphragm physical parameter by measuring the number of ways such as air pressure, vibrating diaphragm displacement, with higher measuring accuracy and preferable stability.
Description
Technical field
A kind of the present invention relates to loudspeaker field tests, more particularly to diaphragm of loudspeaker test with controlled excitation source
Instrument.
Background technology
Loudspeaker is a kind of electricity-power-sonic transducer, is the critical elements in stereo set.Vibrating diaphragm is used as inside loudspeakers
Vitals, directly affect speaker performance parameter.It is therefore desirable to a kind of reliable and stable method of testing and build according to this
Tester the diaphragm of loudspeaker is tested.
Traditional testing scheme further promotes vibrating diaphragm by speaker drive air;By pressure sensor or laser
Sensor catching the amplitude curve of vibrating diaphragm to be measured, so as to obtain the resonant frequency Fo value of vibrating diaphragm.
For example sonic transducer used in 201788018 U of patent CN, picks up the pressure change of cavity, obtains film to be measured
The resonant frequency Fo value of piece;This method needs chamber pressure change to have obvious formant in actual test, if to be measured
The Q values of vibrating diaphragm are relatively low, and the error of Fo test results can be larger, loses the meaning of test.
The amplitude of laser pickup vibrating diaphragm to be measured used in 104125532 A of another patent CN, obtains the humorous of diaphragm to be measured
Vibration frequency Fo values.
But due to effectively not monitoring for drive the speaker, therefore the stability of system is driven this system
The impact of unit is larger, also compares simultaneously for vibrating diaphragm to be measured and the bubble-tight requirement between test fixture high;In practical application
In have a lot of limitation.
Accordingly, it would be desirable to new incentive program, solves the shortcoming of prior art, measuring accuracy and stability is lifted.
Content of the invention
It is an object of the present invention to a kind of diaphragm of loudspeaker tester with controlled excitation source is proposed, by gas
The parameters such as pressure, displacement carry out process and obtain diaphragm of loudspeaker mechanics and parameters,acoustic.
Further object is that proposing a kind of vibration measuring film laying state for the treatment of carries out the scheme of monitor in real time.
Another object of the present invention is to propose a kind of vibrating diaphragm adjustment pumping signal for different size, type, carries
Rise the self-adaptative adjustment scheme of test accuracy.
It is that the present invention is employed the following technical solutions up to this purpose:
A kind of diaphragm of loudspeaker tester with controlled excitation source, for test loudspeaker vibrating diaphragm, which includes:
Platform to be measured, controlled excitation source, laser displacement sensor, control device;
Vibrating diaphragm to be measured is fixed on platform to be measured, and laser displacement sensor is fixed on platform to be measured;Preferably, vibration measuring is treated
Film is co-axially located on platform to be measured with laser displacement sensor;
Control signal is input into controlled excitation source by control device, and controlled excitation source produces excitation letter according to the control signal
Number;
Pumping signal excitation of the vibrating diaphragm to be measured produced by controlled excitation source produces vibration;
Vibration information during laser displacement sensor detection diaphragm oscillations.
A kind of preferred tester, wherein,
The controlled excitation source is loudspeaker driving source;Preferably, the loudspeaker driving source is that band baroceptor is anti-
The loudspeaker excitation system of feedback;
Preferably, baroceptor, the air pressure change between baroceptor detection controlled excitation source and vibrating diaphragm are also included;
Preferably, a closed cavity structure is formed between the loudspeaker driving source and the vibrating diaphragm to be measured;Preferably, seal
Close inside cavity and baroceptor is set, baroceptor is used for detecting that seal cavity inner and outer air pressure is poor;Preferably, flat by test
Platform forms a closed cavity structure between the loudspeaker driving source and the vibrating diaphragm to be measured;
It is furthermore preferred that the baroceptor can be:Probe type microphone, Electret Condencer Microphone, the wheat of mems structures
The combination of gram wind, special mems baroceptors or special mems baroceptors;It is furthermore preferred that described special mems air pressure transmissions
Sensor is combined, and including the mems baroceptors that a broadband frequency band is 0Hz~1kHz, and a high-resolution resolution ratio is excellent
Mems microphones in 1mPa;
Preferably, there is data processor also, test result is processed;Preferably, data processor is by treating
Survey the vibration information that the diaphragm of loudspeaker produces to be processed, vibrating diaphragm resonant frequency Fo values, Q value, pliable can be obtained
Mechanics and the parameters,acoustics such as Cms, oscillating mass Mms, displacement curve;
Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, or many based on laser
The general laser vibrometer sensor for strangling effect.
A kind of preferred tester, wherein,
The controlled excitation source is the stepping push-rod electric machine excitation system with baroceptor feedback;
Preferably, test chamber is formed by platform to be measured between stepping push-rod electric machine and vibrating diaphragm to be measured;Preferably, in test chamber
Baroceptor is placed, poor for detecting seal cavity inner and outer air pressure;
Preferably, the stepping push-rod electric machine pusher cylinder produces controlled air-flow;
Preferably, test chamber of the air-flow by the conducting tube of sealing to platform to be measured;Preferably, sealing duct can be with
It is silicone tube or metal tube;
Preferably, table top fixed placement to be measured vibrating diaphragm to be measured, the coaxial top of vibrating diaphragm to be measured arrange laser displacement sensing
Device, for detecting the parameters such as vibrating diaphragm amplitude, speed, acceleration;
Preferably, there is data processor also, test result is processed;Preferably, data processor is by treating
Survey the vibration information that the diaphragm of loudspeaker produces to be processed, vibrating diaphragm resonant frequency Fo values, Q value, pliable can be obtained
Mechanics and the parameters,acoustics such as Cms, oscillating mass Mms, displacement curve;
Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, or many based on laser
The general laser vibrometer sensor for strangling effect.
A kind of preferred tester, wherein,
The controlled excitation source is the cylinder excitation system with baroceptor feedback;
Preferably, sealing test chamber is formed by platform to be measured between cylinder and vibrating diaphragm to be measured;Preferably, in sealing test chamber
Baroceptor is placed, poor for detecting seal cavity inner and outer air pressure;
The cylinder pusher cylinder produces controlled air-flow;
Test chamber of the air-flow by the conducting tube of sealing to platform to be measured;Preferably, sealing duct can be silica gel
Pipe or metal tube;
Preferably, table top fixed placement to be measured vibrating diaphragm to be measured, the coaxial top of vibrating diaphragm to be measured arrange laser displacement sensing
Device, for detecting the parameters such as vibrating diaphragm amplitude, speed, acceleration;
Preferably, there is data processor also, test result is processed;Preferably, data processor is by treating
Survey the vibration information that the diaphragm of loudspeaker produces to be processed, vibrating diaphragm resonant frequency Fo values, Q value, pliable can be obtained
Mechanics and the parameters,acoustics such as Cms, oscillating mass Mms, displacement curve;
Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, or many based on laser
The general laser vibrometer sensor for strangling effect;
Preferably, in test, cylinder loads air pressure;It is located at the vibrating diaphragm above annular seal space and is promoted generation deformation, air pressure
Sensor, laser displacement sensor detect initial gas pressure initial value and displacement initial value simultaneously;Preferably, annular seal space is present specially
With leakage device, slow gas leakage in cavity, it is free laying state that vibrating diaphragm is slowly replied;Preferably, the process that replys in vibrating diaphragm
In simultaneously detect air pressure change value and change in displacement value;Preferably, to the suitable of vibrating diaphragm can be obtained after the process of above testing result
The parameters such as property Cms, resonant frequency value Fo.
A kind of preferred tester, wherein,
The controlled excitation source is voice coil motor excitation system;Preferably, by voice coil motor as driving source;
Preferably, the voice coil motor excitation system resonant frequency need to be less than the resonant frequency of vibrating diaphragm to be measured;
Preferably, vibrating diaphragm fixed placement to be measured between platform to be measured, the voice coil motor and the vibrating diaphragm to be measured without gas
Close property is required;Preferably, baroceptor need not be placed between the voice coil motor and the vibrating diaphragm to be measured;
Preferably, the coaxial top of vibrating diaphragm to be measured arranges laser displacement sensor, for detecting vibrating diaphragm amplitude, speed, acceleration
The parameters such as degree;
Including cantilever, cantilever outer end is fixed on test platform, and cantilever core fixes vibrating diaphragm to be measured.Cantilever is by least
One muscle connection central area and perimeter;
Preferably, adjusted by the shape of muscle, quantitative design, or material, the thickness adjustment of cantilever itself, adjust voice coil loudspeaker voice coil
The resonant frequency of motor oscillating part, makes voice coil motor oscillating component resonant frequency be less than vibrating diaphragm resonant frequency to be measured;
Preferably, voice coil motor pushes directly on Platform Vibration to be measured, and platform to be measured drives and is fixed on treating on platform to be measured
Survey diaphragm oscillations;When the voice coil motor driving frequency is identical with vibrating diaphragm resonant frequency, vibrating diaphragm resonates;Laser displacement sensor
The information such as amplitude of the vibrating diaphragm under different driving frequencies can be detected, can draw vibrating diaphragm by process being carried out to test data
Resonant frequency Fo value and vibrating diaphragm Q value;
Preferably, there is data processor also, test result is processed;Preferably, data processor is by treating
Survey the vibration information that the diaphragm of loudspeaker produces to be processed, vibrating diaphragm resonant frequency Fo values, Q value, pliable can be obtained
Mechanics and the parameters,acoustics such as Cms, oscillating mass Mms, displacement curve;
Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, or many based on laser
The general laser vibrometer sensor for strangling effect.
A kind of method of test loudspeaker vibrating diaphragm, wherein,
Aforementioned arbitrary tester is provided;
Control signal is input into controlled excitation source by control device, and controlled excitation source produces excitation letter according to the control signal
Number;
Pumping signal excitation of the vibrating diaphragm to be measured produced by controlled excitation source produces vibration;
Vibration information during laser displacement sensor detection diaphragm oscillations.
Preferably, according to the air-tightness between the different adjustment test platforms and driving source of driving source mode, controlled excitation
Using seal cavity when source is the driving source of baroceptor feedback, without the need for seal cavity when controlled excitation source is voice coil motor;
Preferably, the frock of fixed vibrating diaphragm can be with horizontal direction translation adjustment;The support of fixed laser displacement transducer can
Adjusted with vertical direction up and down.Laser displacement sensor is made to focus on vibrating diaphragm to be measured.
A kind of preferred method, wherein,
The draught head being arranged between the baroceptor pickup inside cavity of inside cavity and external atmosphere pressure, and feed back
Give data processor;
Laser displacement sensor pickup vibrating diaphragm displacement, speed, acceleration signal, and feed back to data processor;
Data processor adjusts excitation amplitude according to feedback signal, it is ensured that different vibrating diaphragms to be measured have suitable amplitude, carry
Rise laser displacement sensor detection signal-to-noise ratio;
Preferably, for the diaphragm of loudspeaker, preliminary survey calibration is first carried out;
Preferably, when vibrating diaphragm test is carried out, in closed cavity gas during the baroceptor real-time monitoring diaphragm oscillations
Pressure and the difference of external atmosphere pressure.When vibrating diaphragm is not in place and there is leakage, baroceptor testing result occurs abnormal.
Abnormal signal is fed back to data processor by baroceptor, and points out user to reappose vibrating diaphragm to be measured, confirms to treat vibration measuring
Can continue to test after sealing is kept between film and excitation loudspeaker.
Preferably, during test, data processor obtains the test result of two kinds of baroceptors simultaneously.System first-selection high score
Resolution mems microphone test result, but when measuring air pressure value is more than mems microphone ranges, system chooses special width automatically
Frequency band mems baroceptor test results.
Preferably, the mode for obtaining the pliable parameter of vibrating diaphragm is as follows:Vibrating diaphragm stress and displacement relation curve, F=Δ p*s,
Δ p is vibrating diaphragm both sides draught head, and s effectively vibrates area for vibrating diaphragm;Baroceptor detects Δ p, and vibrating diaphragm open area s is by work
Dress determines;Vibrating diaphragm stressK is the vibrating diaphragm coefficient of stiffiness, and Cms is pliable coefficient;SoIn coefficient a be constant, through air pressure sensing
After the parameters such as device measurement Δ p, laser displacement sensor measurement x, a can be drawn by test result the Fitting Calculation, due to s
Know,The pliable parameter of vibrating diaphragm can be obtained.
A kind of preferred method, wherein,
Stepping push-rod electric machine provides low frequency air pressure,
Preferably, low frequency air pressure can improve the precision of test vibrating diaphragm quasistatic parameter and nonlinear parameter;
Preferably, test chamber is formed by platform to be measured between stepping push-rod electric machine and vibrating diaphragm to be measured, in chamber, places air pressure transmission
Sensor, poor for detecting seal cavity inner and outer air pressure.
A kind of preferred method, wherein,
In test, cylinder loads air pressure;It is located at the vibrating diaphragm above annular seal space and is promoted generation deformation, baroceptor,
Laser displacement sensor detects initial gas pressure initial value and displacement initial value simultaneously;
Preferably, there is special leakage device in annular seal space, slow gas leakage in cavity, and it is freely to place shape that vibrating diaphragm is slowly replied
State;
Preferably, air pressure change value and change in displacement value are detected during vibrating diaphragm reply simultaneously;
Preferably, to the parameters such as pliable Cms, the resonant frequency value Fo of vibrating diaphragm can be obtained after the process of above testing result.
A kind of preferred method, wherein,
Voice coil motor pushes directly on Platform Vibration to be measured, and platform to be measured drives the vibrating diaphragm to be measured being fixed on platform to be measured to shake
Dynamic;
When the voice coil motor driving frequency is identical with vibrating diaphragm resonant frequency, vibrating diaphragm resonates;
Laser displacement sensor can detect the information such as amplitude of the vibrating diaphragm under different driving frequencies;
By process is carried out to test data can draw vibrating diaphragm resonant frequency Fo values and vibrating diaphragm Q value;
Preferably, by the shape of adjustment muscle, the material of quantity or adjustment cantilever itself, thickness, voice coil motor is adjusted
The resonant frequency of oscillating component, makes voice coil motor oscillating component resonant frequency less than vibrating diaphragm resonant frequency to be measured, finally makes laser
Displacement transducer can accurately detect the physical parameters such as the resonant frequency of vibrating diaphragm to be measured;
Preferably, for the diaphragm of loudspeaker, need first to carry out preliminary survey calibration.Laser displacement sensor pickup vibrating diaphragm displacement,
Speed, acceleration signal, and feed back to data processor.Data processor adjusts excitation amplitude according to feedback signal, it is ensured that no
There are suitable amplitude, improving laser displacement transducer detection signal-to-noise ratio with vibrating diaphragm to be measured;
Preferably, when vibrating diaphragm test is carried out, such as vibrating diaphragm is not in place, and laser displacement sensor testing result occurs different
Often;Abnormal signal is fed back to data processor by laser displacement sensor, and points out user to reappose vibrating diaphragm to be measured, is confirmed
Can continue to test after vibrating diaphragm laying state to be measured is good;
Preferably, F can directly be measured by resonance method0:
Wherein mmsFor the equivalent oscillating mass of vibrating diaphragm, CmsPliable for vibrating diaphragm.Application voice coil motor swashs
Shake, voice coil motor motion oscillations part mass mv, vibrating diaphragm fixing tool quality mj, diaphragm mass m to be measuredd, cantilever equivalent mass
ms.Gross mass M=mv+mj+md+ms.Voice coil motor thrust Fv=BL*I, in low-frequency range FvWith shell fragment stress balance, in vibrating diaphragm
F near resonant frequencyvBalance with M*a, i.e. Fv=M*a=BL*I, as mass of system is constant, BL values are constant, input current is not
Become, so speedFor weighing.But when vibrating diaphragm forced vibration to be measured produces resonance, acceleration will be folded on steady state value
Plus the extra acceleration a that vibrating diaphragm forced vibration to be measured is producedt=a+a ', wherein atFor total acceleration, a is that basic and speed, a ' are
Coriolis acceleration when vibrating diaphragm to be measured resonates.A ' is such as identical with a phase places, then atIncrease, such as opposite in phase, then atReduce.
Beneficial effects of the present invention are:
A kind of vibrating diaphragm tester with controlled excitation source proposed by the present invention, data processor therein is by controlled signal
Input controlled excitation source, controlled excitation source produce pumping signal.Vibrating diaphragm to be measured is fixed on platform to be measured, laser displacement sensor
It is fixed on platform, directly over vibrating diaphragm axial direction.The pumping signal that controlled excitation source is produced encourages diaphragm oscillations to be measured, air pressure
Air pressure change between sensor detection controlled excitation source and vibrating diaphragm, the displacement, speed during laser displacement sensor detection diaphragm oscillations
The information such as degree and acceleration.Data processor carries out computing, display to test result.By testing to the diaphragm of loudspeaker,
Mechanics and the acoustics such as vibrating diaphragm resonant frequency Fo values, Q value, pliable Cms, oscillating mass Mms, displacement curve can be obtained
Parameter.
A kind of vibrating diaphragm tester with controlled excitation source proposed by the present invention, needs first to carry out preliminary survey calibration.It is arranged at
Draught head between the baroceptor pickup inside cavity of inside cavity and external atmosphere pressure, or by laser displacement sensor
The parameters such as pickup vibrating diaphragm displacement, and feed back to data processor.Data processor adjusts excitation amplitude according to feedback signal, it is ensured that
Different vibrating diaphragms to be measured have suitable amplitude, lift baroceptor, laser displacement sensor detection signal-to-noise ratio.
A kind of vibrating diaphragm tester with controlled excitation source proposed by the present invention, when vibrating diaphragm test is carried out, the air pressure
In closed cavity air pressure and the difference of external atmosphere pressure during sensor real-time monitoring diaphragm oscillations, or by laser displacement sensor
The parameters such as pickup vibrating diaphragm displacement.When vibrating diaphragm is not in place, there is exception in baroceptor testing result, or laser displacement is passed
Sensor testing result exception.Abnormal signal feeds back to data processor, and points out user to reappose vibrating diaphragm to be measured, confirms to treat
Can continue to test after sealing is kept between vibration measuring film and excitation loudspeaker.
Baroceptor can monitor whether vibrating diaphragm is in place simultaneously, leakage phenomenon such as occur, and pneumatic parameter occurs different
Often, abnormal signal feedback data processor is finally shown and is pointed out user to reappose vibrating diaphragm to be measured by baroceptor.
Another effect of baroceptor is:Preliminary survey calibration is carried out to the diaphragm of loudspeaker of different size, type, by gas
Pressure signal feedback data processor, data processor adjust excitation source signal amplitude according to feedback signal, make different loudspeakers shake
Film is excited enough amplitudes, it is therefore an objective to lift test system and test precision and stability.
Description of the drawings
Fig. 1 is the system connection diagram that the embodiment of the present invention one is provided;
Fig. 2 is the schematic appearance that the embodiment of the present invention one is provided;
Fig. 3 is the partial section that the embodiment of the present invention one is provided;
Fig. 4 is the pressure difference and displacement measurement result that the embodiment of the present invention one is provided;
Fig. 5 is the test result process that the embodiment of the present invention one is provided, speed and pressure difference ratio;
Fig. 6 is the schematic appearance that the embodiment of the present invention two is provided;
Fig. 7 is the draught head and displacement measurement result that the embodiment of the present invention two is provided;
Vibrating diaphragm displacement to be measured shown in Fig. 8 and stress relation test result;
Fig. 9 is the schematic appearance that the embodiment of the present invention three is provided;
Figure 10 is the system connection diagram that the embodiment of the present invention four is provided;
Figure 11 is the schematic appearance that the embodiment of the present invention four is provided;
Figure 12 is the partial section that the embodiment of the present invention four is provided;
Figure 13 is the cantilever outside drawing that the embodiment of the present invention four is provided;
Figure 14 is the cantilever beam system fundamental frequency modal vibration mode simulation result that the embodiment of the present invention four is provided;
Figure 15 is the vibrating diaphragm fundamental frequency modal vibration mode simulation result to be measured that the embodiment of the present invention four is provided;
Figure 16 is the test curve that the embodiment of the present invention four is provided.
In figure,
1st, driving source;101st, loudspeaker;102nd, stepping push-rod electric machine;103rd, cylinder;104th, voice coil motor;
2nd, baroceptor;
3rd, platform to be measured;301st, upper pressing tool;302nd, lower pressing tool;303rd, base station;304th, base;305th, support;
306th, height adjustment knob;307th, vibrating diaphragm fixing tool;
4th, laser displacement sensor;
5th, data processor;501 control devices;502nd, signal pre-processing module;503rd, data acquisition and computing module;
504th, display device;505th, computer;
6th, vibrating diaphragm to be measured;
7th, cantilever;
801st, vibrating mass;802nd, voice coil loudspeaker voice coil;803rd, top flat;804th, magnet;805th, magnetic bowl;
9th, leak holes
Specific embodiment
Technical scheme is further illustrated below in conjunction with the accompanying drawings and by specific embodiment.
Embodiment one
The present embodiment provides a kind of diaphragm of loudspeaker tester with controlled excitation source, and controlled excitation source chooses band air pressure
The loudspeaker excitation system of sensor feedback, system connection diagram are as shown in Figure 1.The present embodiment includes:1st, driving source;2nd, gas
Pressure sensor;3rd, platform to be measured;4th, laser displacement sensor;5th, data processor;501st, control device;502nd, Signal Pretreatment
Module;503rd, data acquisition and computing module;504th, display device;505th, computer.Wherein, control 501, Signal Pretreatment mould
Block 502, data acquisition and computing module 503, display device 504, computer 505 are referred to as data processor 5.
Control device 501 is used for 1 output drive signal of driving source;Signal processing module 502 is used for receiving air pressure sensing
Device 2,4 detection signal of laser displacement sensor, and transmit to data acquisition and computing module 503 and computer 505;Data acquisition
It is used for carrying out the input signal for processing and adjusting control device 501 to detection signal with computing module 503 and computer 505;
Display device 504 is used for the display of test result.
Fig. 2 is the schematic appearance that the present embodiment is provided.Including platform to be measured 3, laser displacement sensor 4, vibrating diaphragm to be measured
6.Wherein, platform to be measured includes:301st, upper pressing tool;302nd, lower pressing tool;303rd, base station;304th, base;305th, support;
306th, height adjustment knob.Vibrating diaphragm to be measured 6 is fixed with lower pressing tool 302 by upper pressing tool 301.Lower pressing tool 302 with
Base station 303 is combined, and forms airtight cavity.Base station 303 is fixed on base 304.Laser displacement sensor 4 is placed in support 305
On, directly over 6 axial direction of vibrating diaphragm to be measured, by height adjustment knob control height, realize focusing.
Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, or many based on laser
The general laser vibrometer sensor for strangling effect.
Fig. 3 is the partial section that the present embodiment is provided, including 101, loudspeaker;2nd, baroceptor;301st, upper pressing
Frock;302nd, lower pressing tool;303rd, base station;6th, vibrating diaphragm to be measured.The placement loudspeaker 101 of inside cavity is located on base station 303;
Inside cavity is located on base station 303 places baroceptor 2 simultaneously.Preferably, the loudspeaker driving source treats vibration measuring with described
One closed cavity structure of intermembranous formation;Preferably, baroceptor is set inside closed cavity, and baroceptor is used for detecting
Seal cavity inner and outer air pressure is poor;Preferably, one is formed by test platform between the loudspeaker driving source and the vibrating diaphragm to be measured
Individual closed cavity structure;
It is furthermore preferred that the baroceptor can be:Probe type microphone, Electret Condencer Microphone, the wheat of mems structures
The combination of gram wind, special mems baroceptors or special mems baroceptors;It is furthermore preferred that described special mems air pressure transmissions
Sensor is combined, including a broadband mems baroceptor, and a high-resolution mems microphone;Preferably, the width
Frequency band mems baroceptors frequency band is 0Hz~1kHz, and the high-resolution mems microphone resolution ratio is better than 1mPa;
During test, loudspeaker 101 vibrates, and makes seal cavity air pressure inside change, and encourages vibrating diaphragm 6 to be measured to vibrate, gas
The detection annular seal space air pressure inside change of pressure sensor 2, the displacement, speed when laser displacement sensor 4 detects that vibrating diaphragm to be measured 6 vibrates
With information such as acceleration.Data processor 5 carries out computing, display to test result.Tested by treating vibration measuring film 6, can
To obtain mechanics and the parameters,acoustics such as resonant frequency Fo value, Q value, pliable Cms, oscillating mass Mms, displacement curve.
Preferably, there is data processor also, test result is processed;Preferably, data processor is by treating
Survey the vibration information that the diaphragm of loudspeaker produces to be processed, vibrating diaphragm resonant frequency Fo values, Q value, pliable can be obtained
Mechanics and the parameters,acoustics such as Cms, oscillating mass Mms, displacement curve;
Fig. 4 is the draught head of the present embodiment offer, displacement measurement result.In figure, C1 is draught head test result, and C2 is position
Move test result.There are two peaks in 100Hz to 3000Hz in curve C1 and C2, and C1 and C2 is at about 450Hz due to loudspeaker 101
Couple with annular seal space and peak occur.The peak value of C1 and C2 about 1300Hz place appearance is resonated generation by vibrating diaphragm to be measured 6.Specifically, C1 peaks
Value frequency 1348Hz, C2 crest frequencies are the peak that the crest frequency of 1306Hz, C1 and C2 near 1300Hz is subject near 450Hz
Value affects, and C1 and C2 crest frequencies are unequal.
Fig. 5 is the present embodiment offer test result is processed, speed and pressure difference ratio.Known formula v=d*
2* π * f, wherein v representation speeds, d represent displacement, and f represents frequency.According to displacement measurement result and above-mentioned formula in figure, can be with
Calculate speed v.Speed v and pressure difference p test results are done ratio, the ratio curve in Fig. 5 can be obtained.Ratio curve is only
There is a peak, peak is in 1258Hz.Speed v is done ratio with pressure difference p, loudspeaker, annular seal space pair can be effectively removed
The impact of test result.Conventional loudspeakers vibrating diaphragm tester only tests displacement curve by laser displacement sensor at present, passes through
Extract displacement or speed, acceleration peak value position draw vibrating diaphragm resonant frequency to be measured, it is impossible to avoid encouraging the parts pair such as loudspeaker
The impact of vibrating diaphragm to be measured, the present embodiment acquired results are more accurate.
The present embodiment before official testing is started needs first to carry out preliminary survey calibration.It is arranged at the air pressure sensing of inside cavity
Draught head between the pickup inside cavity of device 2 and external atmosphere pressure, and feed back to data processor 5.Data processor 5 is according to anti-
Feedback signal adjusts excitation amplitude, it is ensured that different vibrating diaphragms to be measured have suitable amplitude, lifts baroceptor, laser displacement sensing
Device detection signal-to-noise ratio.
The present embodiment during vibrating diaphragm test is carried out, when 2 real-time monitoring of baroceptor vibrating diaphragm 6 to be measured vibrates
In closed cavity air pressure and the difference of external atmosphere pressure.When vibrating diaphragm to be measured 6 is not in place, 2 testing result of baroceptor goes out
Now abnormal.Abnormal signal feeds back to data processor 5, points out user to reappose vibrating diaphragm to be measured, confirms vibrating diaphragm 2 to be measured and swashs
Encouraging can continue to test after sealing being kept between source 1.
Embodiment two
The present embodiment provides a kind of diaphragm of loudspeaker tester with controlled excitation source, and controlled excitation source chooses band air pressure
The cylinder of sensor feedback, system connection diagram are as shown in Figure 1.The system connection of the present embodiment data processor 5, data inspection
Survey mode is similar to embodiment one, and only driving source 1 is changed into cylinder 103 from loudspeaker 101.
Fig. 6 is the schematic appearance that the present embodiment is provided.Vibrating diaphragm to be measured 6 is by upper pressing tool 301 and lower pressing tool 302
Fixed.Lower pressing tool 302 is combined with base station 303, forms airtight cavity, and annular seal space arranges leak holes 9.Arrange on base station 303
Passage, is connected by tracheae with cylinder 103.Base station 303 is assembled on base 304, and horizontal level is adjustable.It is located on base station 303
Inside cavity places baroceptor 2.Laser displacement sensor 4 is fixed on 3 on test platform, and laser displacement sensor 4 is laid
On support 305, directly over 6 axial direction of vibrating diaphragm to be measured, by height adjustment knob control height, focusing is realized.
Excitation system of the cylinder 103 as vibrating diaphragm tester, in test, cylinder 103 loads air pressure.It is located on annular seal space
The vibrating diaphragm to be measured 6 of side is promoted to produce deformation, and baroceptor 2, laser displacement sensor 4 detect that initial gas pressure is initial simultaneously
Value and displacement initial value.Annular seal space setting leak 9, slow gas leakage in cavity, the slow reply of vibrating diaphragm to be measured 6 is freely to place shape
State.Air pressure change value and change in displacement value are detected during vibrating diaphragm to be measured 6 is replied simultaneously.After to the process of above testing result
The parameters such as the pliable Cms of vibrating diaphragm can be obtained, vibrating diaphragm weight Mms is, it is known that formula can be passed throughCalculate
Draw the Fo values of vibrating diaphragm to be measured 6.
The present embodiment can be detected and be fed back to data processor 5 by baroceptor 2 to inside cavity air pressure, real
Now the excitation amplitude of different vibrating diaphragms to be measured 6 is adjusted and test process in real-time monitoring vibrating diaphragm 6 to be measured whether place exception.Pass through
Baroceptor 2, laser displacement sensor 4 are treated vibration measuring film 6 and are tested, and carry out computing through data processor 5, obtain resonance
Mechanics and the parameters,acoustics such as frequency Fo value, Q value, pliable Cms, oscillating mass Mms, displacement curve.
Fig. 7 is the present embodiment draught head and displacement measurement result.In figure, C4 is that draught head changes over test result, C5
It is that displacement changes over test result.During test, with pressurization is stopped after 103 quick load pulses air pressure of cylinder immediately, close
Closed chamber inside and outside draught head reaches maximum in 100ms.Annular seal space arranges leak holes 9, is gradually reduced inside cavity air pressure,
Curve C4 rapid increases before 100ms be can be seen that from Fig. 7 C4 curves, maximum 1000pa during 100ms, is reached;Open from 100ms
Begin, C4 slowly declines, and finally in 500ms, draught head is kept to 0pa substantially, illustrates that annular seal space internal-external air pressure is basically identical.
Due to annular seal space inner and outer air pressure inconsistent, vibrating diaphragm stress deformation to be measured, deformation quantity and air pressure difference correlation.Vibrating diaphragm is represented in Fig. 7
The curve C5 of displacement measurement result rapid increases before 100ms, at 100ms reach maximum 400um, start to subtract from 100ms
Little, and 0um is reduced to substantially in 500ms.Draught head Δ P maximum 1000pa such as extracted, and maximum displacement value d is 400um, and
6 effective vibration plane s of known vibrating diaphragm to be measured products are 1cm2, then formula can be passed throughCalculate CmsPosition
4mm/N.Vibrating diaphragm weight Mms is, it is known that formula can be passed throughCalculate the Fo values of vibrating diaphragm to be measured 6.
If using the air pressure difference of 0ms to 100ms time periods in Fig. 7 as the longitudinal axis, vibrating diaphragm shift value to be measured, can used as transverse axis
To obtain 6 displacement of vibrating diaphragm to be measured as shown in C6 in Fig. 8 and draught head relation curve, when 6 displacement of vibrating diaphragm to be measured is less, can be with
Be approximately considered displacement linear relationship is met with draught head.According to displacement in Fig. 8 with the fitting of draught head relation curve can be
A is counted, the relation of coefficient a Cms pliable with vibrating diaphragm to be measured isWherein s is effective vibration area of vibrating diaphragm to be measured 6, institute
It is 4mm/N to obtain Cms values.Meanwhile, vibrating diaphragm to be measured 6 can be calculated in difference according to the present embodiment gained draught head, displacement result
The pliable value of position, when 6 displacement of vibrating diaphragm to be measured is less, pliable Cms values are constant, when 6 displacement of vibrating diaphragm to be measured is larger, pliable
Cms values diminish, so as to realize the research to diaphragm materials and deformational nonlinearity.
Embodiment three
The present embodiment provides a kind of diaphragm of loudspeaker tester with controlled excitation source, and controlled excitation source chooses band air pressure
The stepping push-rod electric machine excitation system of sensor feedback, system connection diagram are as shown in Figure 1.The present embodiment data processor 5
System connection, Data Detection, data processing method similar to embodiment two, only driving source 1 is changed into stepping push rod from cylinder 103
Motor 102.
Fig. 9 is the schematic appearance that the present embodiment is provided.Vibrating diaphragm to be measured 6 is by upper pressing tool 301 and lower pressing tool 302
Fixed.Lower pressing tool 302 is combined with base station 303, forms airtight cavity.Passage is set on base station 303, with stepping push-rod electric machine
102 are connected by tracheae.Base station 303 is assembled on base 304, and horizontal level is adjustable.Place positioned inside cavity on base station 303
Baroceptor 2.Laser displacement sensor 4 is fixed on 3 on test platform, and laser displacement sensor 4 is placed on support 305,
The axially surface of vibrating diaphragm to be measured 6 is located at, by height adjustment knob control height, realizes focusing on.
The present embodiment is detected and is fed back to data processor 5 by baroceptor 2 to inside cavity air pressure, is realized
Whether exception is placed to real-time monitoring vibrating diaphragm 6 to be measured in the adjustment of the excitation amplitude of different vibrating diaphragms to be measured 6 and test process.By gas
Pressure sensor 2, laser displacement sensor 4 are treated vibration measuring film 6 and are tested, and carry out computing through data processor 5, obtain resonance frequency
Mechanics and the parameters,acoustics such as rate Fo value, Q value, pliable Cms, oscillating mass Mms, displacement curve.
Compared with the cylinder 103 provided with embodiment two, the present embodiment stepping push-rod electric machine 102 stably can provide controllable
Low frequency air pressure, and the cylinder 103 in embodiment two can only provide pulse pressure, and embodiment two to need leakage device to make close
Envelope chamber is slowly revealed, and the present embodiment is without the need for additionally arranging leak holes 9.The present embodiment is carried by 102 gas testing pressure of stepping push-rod electric machine
Ascending, descending is low, controllable have the advantages that stable gas pressure.
The present embodiment can pass through draught head, displacement song with embodiment two for the mode of data sampling and processing is consistent
Line, calculates 6 pliable Cms values of vibrating diaphragm to be measured by modes such as fittings, it is known that diaphragm mass Mms, can calculate vibrating diaphragm to be measured 6
Resonant frequency Fo value.Compared with passing through vibrating diaphragm resonance method with current conventional loudspeakers vibrating diaphragm tester, the embodiment of the present invention two, enforcement
Three drawn resonant frequency value Fo of example compares more accurate, stable, and test result not tested person system incentive source, structural member etc.
Interference.
Example IV
The present embodiment proposes a kind of diaphragm of loudspeaker tester with controlled excitation source, and controlled excitation source chooses voice coil loudspeaker voice coil electricity
Machine, system connection diagram are as shown in Figure 10.The present embodiment includes:1st, driving source;3rd, platform to be measured;4th, laser displacement sensing
Device;5th, data processor;501st, control device;502nd, signal pre-processing module;503rd, data acquisition and computing module;504th, existing
Reality and control module;505th, computer.Wherein, control device 501, signal pre-processing module 502, data acquisition and computing module
503rd, reality is referred to as data processor 5 with control module 504, computer 505.
Control device 501 is used for 1 output drive signal of driving source;Signal processing module 502 is used for receiving laser displacement
4 detection signal of sensor, and transmit to data acquisition and computing module 503 and computer 505;Data acquisition and computing module
503 are used for carrying out the input signal for processing and adjusting control device 501 to detection signal with computer 505;Display device
504 displays for being used for test result.
Figure 11 is the diaphragm of loudspeaker tester schematic appearance with voice coil motor excitation, including:3rd, platform to be measured;4th, swash
Optical displacement sensor;6th, vibrating diaphragm to be measured;7th, cantilever.Wherein, platform to be measured 3 is by 301, upper pressing tool;302nd, lower pressing tool;
303rd, base station;304th, base;305th, support;306th, height adjustment knob composition.Wherein, as the voice coil motor 104 of driving source
Inside base station 303.
Laser displacement sensor 4 is installed on support 305, height adjustment knob 306 can adjust laser displacement sensor 4
Highly, realize focusing on.Voice coil motor 104 is attached on base station 303, and in the placement of base station 303 and base 304, and horizontal level can
Adjustment.Upper pressing tool 301 is used for cantilever mounted 7, cantilever 7, vibrating diaphragm fixing tool 307 and voice coil loudspeaker voice coil electricity with lower pressing tool 302
Machine 104 is by screw locking.Preferably, the coaxial top of vibrating diaphragm to be measured arranges laser displacement sensor, for detecting vibrating diaphragm amplitude, speed
The parameters such as degree, acceleration;Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, Huo Zheji
Laser vibrometer sensor in laser doppler.
Figure 12 is voice coil motor and platform partial section to be measured, including:104th, voice coil motor;301st, upper pressing tool;
302nd, lower pressing tool;303rd, base station;6th, vibrating diaphragm to be measured;7th, cantilever.Voice coil motor 104 is by 801, vibrating mass;802nd, voice coil loudspeaker voice coil;
803rd, top flat;804th, magnet;805th, magnetic bowl composition.
Top flat 803, magnet 804 in voice coil motor 104 is bonding by glue with magnetic bowl 805, forms magnetostatic field, is fixed on base
On platform 303, voice coil loudspeaker voice coil 802 is positioned over magnetostatic field, and top is fixed with vibrating mass 801;Vibrating mass 801, cantilever 7, vibrating diaphragm fixing tool
307 pass through screw locking;Cantilever 7 is fixed by screw locking by upper pressing tool 301, lower pressing tool 302.Preferably, treat
Vibration measuring film fixed placement is required without air-tightness between platform to be measured, the voice coil motor and the vibrating diaphragm to be measured;Preferably, institute
State baroceptor need not be placed between voice coil motor and the vibrating diaphragm to be measured;Preferably, the voice coil motor excitation system is humorous
Vibration frequency need to be less than the resonant frequency of vibrating diaphragm to be measured;
Preferably, voice coil motor pushes directly on Platform Vibration to be measured, and platform to be measured drives and is fixed on treating on platform to be measured
Survey diaphragm oscillations;When the voice coil motor driving frequency is identical with vibrating diaphragm resonant frequency, vibrating diaphragm resonates;Laser displacement sensor
The information such as amplitude of the vibrating diaphragm under different driving frequencies can be detected, can draw vibrating diaphragm by process being carried out to test data
Resonant frequency Fo value and vibrating diaphragm Q value;
Preferably, there is data processor also, test result is processed;Preferably, data processor is by treating
Survey the vibration information that the diaphragm of loudspeaker produces to be processed, vibrating diaphragm resonant frequency Fo values, Q value, pliable can be obtained
Mechanics and the parameters,acoustics such as Cms, oscillating mass Mms, displacement curve;
During test, voice coil motor receives ac signal, and voice coil loudspeaker voice coil 802 is being formed by top flat 803, magnet 804 and magnetic bowl 805
Stress vibrate in magnetostatic field.Voice coil loudspeaker voice coil 802 vibrates vibrating mass 801, cantilever 7, vibrating diaphragm fixing tool 307, and finally makes vibrating diaphragm
Vibrating diaphragm to be measured 6 on fixing tool vibrates.When 104 driving frequency of the voice coil motor is identical with 6 resonant frequency of vibrating diaphragm to be measured,
Vibrating diaphragm to be measured 6 resonates.Now, laser displacement sensor 4 can detect the amplitude of vibrating diaphragm to be measured 6 under different driving frequencies etc.
Information, can draw vibrating diaphragm resonant frequency Fo values and vibrating diaphragm Q value by carrying out process to test data.
In the present embodiment, voice coil motor 104 pushes directly on platform to be measured 3 and vibrates, it is not necessary to which air is directly swashed as medium
Encourage vibrating diaphragm to be measured 6 to vibrate.It is suitable for full range tape test by voice coil motor 104 as driving source, measuring stability is more preferable.
In the present embodiment, for vibrating diaphragm to be measured 6, need first to carry out preliminary survey calibration.The pickup vibrating diaphragm of laser displacement sensor 4 position
Shifting, speed, acceleration signal, and feed back to data processor 5.Data processor 5 adjusts excitation amplitude according to feedback signal, protects
Demonstrate,proving different vibrating diaphragms to be measured 6 has suitable amplitude, 4 detection signal-to-noise ratio of improving laser displacement transducer.
In the present embodiment, when being tested, such as vibrating diaphragm to be measured 6 is not in place, and result is surveyed in laser displacement sensor inspection 4
Occur abnormal.Abnormal signal is fed back to data processor 5 by laser displacement sensor 4, and it is to be measured to point out user to reappose
Vibrating diaphragm 6, confirms to continue to test after 6 laying state of vibrating diaphragm to be measured is good.
Figure 13 is the cantilever outside drawing that the present embodiment is provided, and cantilever outer end is fixed on pressing tool 301, lower pressing tool
Between 302, the vibrating mass 801 of cantilever core and vibrating diaphragm fixing tool 307, voice coil motor 104 is fixed.Cantilever 7 is by some
Bar muscle connection central area and perimeter.Material, thickness by the shape of muscle, quantitative design adjustment or cantilever itself
Adjustment, adjusts the resonant frequency of voice coil motor oscillating component, makes 104 oscillating component resonant frequency of voice coil motor be less than vibrating diaphragm to be measured
6 resonant frequency, finally enables laser displacement sensor 4 accurately detect the physics such as the resonant frequency of vibrating diaphragm to be measured 6 ginseng
Number.
Figure 14, Figure 15 be the present embodiment provide cantilever beam system modal vibration mode simulation result, cantilever vibration system
System includes:Cantilever 7, vibrating diaphragm fixing tool 307, vibrating diaphragm to be measured 6, vibrating mass 801, voice coil loudspeaker voice coil 802.Wherein, cantilever 7 is by 20 " S "
Shape muscle is constituted, and chooses SUS301 stainless steels, and thickness is 0.2mm.Vibrating diaphragm fixing tool 307 chooses SUS301 stainless steels, vibrating mass
801 choose copper, and voice coil loudspeaker voice coil 802 is copper hot blast line, and vibrating diaphragm to be measured 6 is 4um PC.
The cantilever beam system cantilever fundamental vibration Modal Analysis result that Figure 14 is provided for the present embodiment, jib system fundamental frequency
Fo values simulation result is 176Hz.Wherein, dark color is amplitude large area, and light areas are amplitude relative small areas.Cantilever shakes
When dynamic system is vibrated near fundamental frequency, the i.e. 176Hz, 7 mid portion amplitude of cantilever is maximum, and edge is near upper and lower pressing tool
301st, 302 region is substantially without amplitude.
The 6 fundamental vibration Modal Analysis result of vibrating diaphragm to be measured of the cantilever beam system that Figure 15 is provided for the present embodiment, to be measured
6 frequency Fo value simulation results of vibrating diaphragm are for about 1400Hz.Jib system is swashed near 1400Hz and when reaching vibrating diaphragm fundamental resonance frequency
Vibrator film produces resonance.Wherein, dark color is amplitude large area, and light areas are amplitude relative small areas.Vibrating diaphragm to be measured 6
Near fundamental frequency, i.e. 1400Hz, vibrating diaphragm central region amplitude is maximum, and 6 edge of vibrating diaphragm to be measured and cantilever 7 are substantially without amplitude.
The diaphragm of loudspeaker tester product measured result with voice coil motor excitation that Figure 16 is provided for the present embodiment, test
Frequency range is 1000Hz-2000Hz.In figure, when C7 is not for adding vibrating diaphragm, the acceleration frequency response of 307 flat site of vibrating diaphragm fixing tool is bent
Line, C8 are increase by 6 rear film central point acceleration displacement curve of vibrating diaphragm to be measured.Vibrating diaphragm to be measured 6 chooses the 4um of a 9mm diameters
PC earphone diaphragms.It can be seen from fig. 11 that not adding test value of the acceleration of vibrating diaphragm in 1000Hz-2000Hz frequency ranges to exist
50m/s2To 100m/s2Fluctuation.After vibrating diaphragm 6 to be measured is increased, there is peak value in 1420Hz in acceleration, acceleration peak value due to
Vibrating diaphragm resonance causes, and 1420Hz is the resonant frequency Fo value of such vibrating diaphragm to be measured.Meanwhile, acceleration frequency response curve can be entered
Row data processing, obtains the other specifications such as Q value.
By comparing emulation and measured result, vibrating diaphragm Fo values to be measured are emulated basically identical with actual measurement Fo values.
Above in association with the know-why that specific embodiment describes the present invention.These descriptions are intended merely to explain the present invention's
Principle, and limiting the scope of the invention can not be construed to by any way.Based on explanation herein, the technology of this area
Personnel associate other specific embodiments of the present invention by need not paying performing creative labour, these modes fall within
Within protection scope of the present invention.
Claims (10)
1. a kind of diaphragm of loudspeaker tester with controlled excitation source, for test loudspeaker vibrating diaphragm, it is characterised in that bag
Include:
Platform to be measured, controlled excitation source, laser displacement sensor, control device;
Vibrating diaphragm to be measured is fixed on platform to be measured, and laser displacement sensor is fixed on platform to be measured;Preferably, vibrating diaphragm to be measured with
Laser displacement sensor is co-axially located on platform to be measured;
Control signal is input into controlled excitation source by control device, and controlled excitation source produces pumping signal according to the control signal;
Pumping signal excitation of the vibrating diaphragm to be measured produced by controlled excitation source produces vibration;
Vibration information during laser displacement sensor detection diaphragm oscillations.
2. tester according to claim 1, it is characterised in that
The controlled excitation source is loudspeaker driving source;Preferably, the loudspeaker driving source is with baroceptor feedback
Loudspeaker excitation system;
Preferably, baroceptor, the air pressure change between baroceptor detection controlled excitation source and vibrating diaphragm are also included;
Preferably, a closed cavity structure is formed between the loudspeaker driving source and the vibrating diaphragm to be measured;Preferably, closing chamber
Portion arranges baroceptor in vivo, and baroceptor is used for detecting that seal cavity inner and outer air pressure is poor;Preferably, existed by test platform
A closed cavity structure is formed between the loudspeaker driving source and the vibrating diaphragm to be measured;
It is furthermore preferred that the baroceptor can be:Probe type microphone, Electret Condencer Microphone, the microphone of mems structures,
Mems baroceptors or the combination of mems baroceptors;It is furthermore preferred that described mems baroceptors combination, including one
Individual broadband mems baroceptor, and a high-resolution mems microphone;Preferably, the broadband mems air pressure sensing
Device frequency band is 0Hz~1kHz, and the high-resolution mems microphone resolution ratio is better than 1mPa;
Preferably, there is data processor also, test result is processed;Preferably, data processor is by raising to be measured
Sound device vibrating diaphragm produce vibration information processed, can obtain vibrating diaphragm resonant frequency Fo values, Q value, pliable Cms,
The mechanics such as oscillating mass Mms, displacement curve and parameters,acoustic;
Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, or be based on laser-Doppler
The laser vibrometer sensor of effect.
3. according to the tester described in claim 1, it is characterised in that
The controlled excitation source is the stepping push-rod electric machine excitation system with baroceptor feedback;
Preferably, test chamber is formed by platform to be measured between stepping push-rod electric machine and vibrating diaphragm to be measured;Preferably, place in test chamber
Baroceptor, poor for detecting seal cavity inner and outer air pressure;
Preferably, the stepping push-rod electric machine pusher cylinder produces controlled air-flow;
Preferably, test chamber of the air-flow by the conducting tube of sealing to platform to be measured;Preferably, sealing duct can be silicon
Sebific duct or metal tube;
Preferably, table top fixed placement to be measured vibrating diaphragm to be measured, the coaxial top of vibrating diaphragm to be measured arrange laser displacement sensor, use
In parameters such as detection vibrating diaphragm amplitude, speed, acceleration;
Preferably, there is data processor also, test result is processed;Preferably, data processor is by raising to be measured
Sound device vibrating diaphragm produce vibration information processed, can obtain vibrating diaphragm resonant frequency Fo values, Q value, pliable Cms,
The mechanics such as oscillating mass Mms, displacement curve and parameters,acoustic;
Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, or be based on laser-Doppler
The laser vibrometer sensor of effect.
4. according to the tester described in claim 1, it is characterised in that
The controlled excitation source is the cylinder excitation system with baroceptor feedback;
Preferably, sealing test chamber is formed by platform to be measured between cylinder and vibrating diaphragm to be measured;Preferably, place in sealing test chamber
Baroceptor, poor for detecting seal cavity inner and outer air pressure;
The cylinder pusher cylinder produces controlled air-flow;
Test chamber of the air-flow by the conducting tube of sealing to platform to be measured;Preferably, sealing duct can be silicone tube or
Metal tube;
Preferably, table top fixed placement to be measured vibrating diaphragm to be measured, the coaxial top of vibrating diaphragm to be measured arrange laser displacement sensor, use
In parameters such as detection vibrating diaphragm amplitude, speed, acceleration;
Preferably, there is data processor also, test result is processed;Preferably, data processor is by raising to be measured
Sound device vibrating diaphragm produce vibration information processed, can obtain vibrating diaphragm resonant frequency Fo values, Q value, pliable Cms,
The mechanics such as oscillating mass Mms, displacement curve and parameters,acoustic;
Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, or be based on laser-Doppler
The laser vibrometer sensor of effect;
Preferably, in test, cylinder loads air pressure;It is located at the vibrating diaphragm above annular seal space and is promoted generation deformation, air pressure sensing
Device, laser displacement sensor detect initial gas pressure initial value and displacement initial value simultaneously;Preferably, there is special letting out in annular seal space
Leakage device, slow gas leakage in cavity, it is free laying state that vibrating diaphragm is slowly replied;Preferably, same during vibrating diaphragm reply
When detection air pressure change value and change in displacement value;Preferably, to the pliable of vibrating diaphragm can be obtained after the process of above testing result
The parameters such as Cms, resonant frequency value Fo.
5. according to the tester described in claim 1, it is characterised in that
The controlled excitation source is voice coil motor excitation system;Preferably, by voice coil motor as driving source;
Preferably, the voice coil motor excitation system resonant frequency need to be less than the resonant frequency of vibrating diaphragm to be measured;
Preferably, vibrating diaphragm fixed placement to be measured between platform to be measured, the voice coil motor and the vibrating diaphragm to be measured without air-tightness
Require;Preferably, baroceptor need not be placed between the voice coil motor and the vibrating diaphragm to be measured;
Preferably, the coaxial top of vibrating diaphragm to be measured arranges laser displacement sensor, for detecting vibrating diaphragm amplitude, speed, acceleration etc.
Parameter;
Including cantilever, cantilever outer end is fixed on test platform, and cantilever core fixes vibrating diaphragm to be measured.Cantilever is by least one
Muscle connection central area and perimeter;
Preferably, adjusted by the shape of muscle, quantitative design, or material, the thickness adjustment of cantilever itself, adjust voice coil motor
The resonant frequency of oscillating component, makes voice coil motor oscillating component resonant frequency be less than vibrating diaphragm resonant frequency to be measured;
Preferably, voice coil motor pushes directly on Platform Vibration to be measured, and platform to be measured drives to be fixed on treats vibration measuring on platform to be measured
Film vibrates;When the voice coil motor driving frequency is identical with vibrating diaphragm resonant frequency, vibrating diaphragm resonates;Laser displacement sensor can be with
The information such as amplitude of the vibrating diaphragm under different driving frequencies are detected, can draw vibrating diaphragm resonance by process being carried out to test data
Frequency Fo value and vibrating diaphragm Q value;
Preferably, there is data processor also, test result is processed;Preferably, data processor is by raising to be measured
Sound device vibrating diaphragm produce vibration information processed, can obtain vibrating diaphragm resonant frequency Fo values, Q value, pliable Cms,
The mechanics such as oscillating mass Mms, displacement curve and parameters,acoustic;
Preferably, the laser instrument can be the laser displacement sensor based on trigonometry principle, or be based on laser-Doppler
The laser vibrometer sensor of effect.
6. a kind of method of test loudspeaker vibrating diaphragm, it is characterised in that
Control signal is input into controlled excitation source by control unit/device, and controlled excitation source produces excitation according to the control signal
Signal;
Pumping signal excitation of the vibrating diaphragm to be measured produced by controlled excitation source produces vibration;
Vibration information during laser displacement sensor detection diaphragm oscillations.
Preferably, according to the air-tightness between the different adjustment test platforms and driving source of driving source mode, controlled excitation source is
Using seal cavity during the driving source of baroceptor feedback, without the need for seal cavity when controlled excitation source is voice coil motor;
Preferably, the frock of fixed vibrating diaphragm can be with horizontal direction translation adjustment;The support of fixed laser displacement transducer can be erected
Nogata is lower upwards to be adjusted.Laser displacement sensor is made to focus on vibrating diaphragm to be measured.
7. method according to claim 6, it is characterised in that
The draught head being arranged between the baroceptor pickup inside cavity of inside cavity and external atmosphere pressure, and feed back to number
According to processor;
Laser displacement sensor pickup vibrating diaphragm displacement, speed, acceleration signal, and feed back to data processor;
Data processor adjusts excitation amplitude according to feedback signal, it is ensured that different vibrating diaphragms to be measured have suitable amplitude, is lifted and is swashed
Optical displacement sensor detection signal-to-noise ratio;
Preferably, for the diaphragm of loudspeaker, preliminary survey calibration is first carried out;
Preferably, carry out vibrating diaphragm test when, during the baroceptor real-time monitoring diaphragm oscillations closed cavity air pressure with
The difference of external atmosphere pressure.When vibrating diaphragm is not in place and there is leakage, baroceptor testing result occurs abnormal.Air pressure
Abnormal signal is fed back to data processor by sensor, and points out user to reappose vibrating diaphragm to be measured, confirm vibrating diaphragm to be measured with
Can continue to test after sealing is kept between excitation loudspeaker.
Preferably, during test, data processor obtains the test result of two kinds of baroceptors simultaneously.System first-selection high-resolution
Mems microphone test results, but when measuring air pressure value is more than mems microphone ranges, system chooses special broadband automatically
Mems baroceptor test results.
Preferably, the mode for obtaining the pliable parameter of vibrating diaphragm is as follows:Vibrating diaphragm stress and displacement relation curve, F=Δ p*s, Δ p are
Vibrating diaphragm both sides draught head, s effectively vibrate area for vibrating diaphragm;Baroceptor detects Δ p, and vibrating diaphragm open area s is true by frock
Fixed;Vibrating diaphragm stressK is the vibrating diaphragm coefficient of stiffiness, and Cms is pliable coefficient;So In coefficient a be constant, through baroceptor
After measurement Δ p, the laser displacement sensor measurement parameter such as x, a can be drawn by test result the Fitting Calculation, due to s, it is known thatThe pliable parameter of vibrating diaphragm can be obtained.
8. method according to claim 6, it is characterised in that
Stepping push-rod electric machine provides low frequency air pressure,
Preferably, low frequency air pressure can improve the precision of test vibrating diaphragm quasistatic parameter and nonlinear parameter;
Preferably, test chamber is formed by platform to be measured between stepping push-rod electric machine and vibrating diaphragm to be measured, in chamber, places baroceptor,
Poor for detecting seal cavity inner and outer air pressure.
9. method according to claim 6, it is characterised in that
In test, cylinder loads air pressure;It is located at the vibrating diaphragm above annular seal space and is promoted generation deformation, baroceptor, laser
Displacement transducer detects initial gas pressure initial value and displacement initial value simultaneously;
Preferably, there is special leakage device in annular seal space, slow gas leakage in cavity, and it is free laying state that vibrating diaphragm is slowly replied;
Preferably, air pressure change value and change in displacement value are detected during vibrating diaphragm reply simultaneously;
Preferably, to the parameters such as pliable Cms, the resonant frequency value Fo of vibrating diaphragm can be obtained after the process of above testing result.
10. method according to claim 6, it is characterised in that
Voice coil motor pushes directly on Platform Vibration to be measured, and platform to be measured drives the diaphragm oscillations to be measured being fixed on platform to be measured;
When the voice coil motor driving frequency is identical with vibrating diaphragm resonant frequency, vibrating diaphragm resonates;
Laser displacement sensor can detect the information such as amplitude of the vibrating diaphragm under different driving frequencies;
By process is carried out to test data can draw vibrating diaphragm resonant frequency Fo values and vibrating diaphragm Q value;
Preferably, by the shape of adjustment muscle, the material of quantity or adjustment cantilever itself, thickness, adjustment voice coil motor vibration
Partial resonant frequency, makes voice coil motor oscillating component resonant frequency less than vibrating diaphragm resonant frequency to be measured, finally makes laser displacement
Sensor can accurately detect the physical parameters such as the resonant frequency of vibrating diaphragm to be measured;
Preferably, for the diaphragm of loudspeaker, need first to carry out preliminary survey calibration.Laser displacement sensor pickup vibrating diaphragm displacement, speed,
Acceleration signal, and feed back to data processor.Data processor adjusts excitation amplitude according to feedback signal, it is ensured that different to be measured
Vibrating diaphragm has suitable amplitude, improving laser displacement transducer detection signal-to-noise ratio;
Preferably, when vibrating diaphragm test is carried out, such as vibrating diaphragm is not in place, and laser displacement sensor testing result occurs abnormal;
Abnormal signal is fed back to data processor by laser displacement sensor, and points out user to reappose vibrating diaphragm to be measured, confirms to treat
Can continue to test after vibration measuring film laying state is good;
Preferably, F can directly be measured by resonance method0:
Wherein mmsFor the equivalent oscillating mass of vibrating diaphragm, CmsPliable for vibrating diaphragm.Application voice coil motor exciting,
Voice coil motor motion oscillations part mass mv, vibrating diaphragm fixing tool quality mj, diaphragm mass m to be measuredd, cantilever equivalent mass ms.Always
Mass M=mv+mj+md+ms.Voice coil motor thrust Fv=BL*I, in low-frequency range FvWith shell fragment stress balance, vibrating diaphragm resonance frequency
F near ratevBalance with M*a, i.e. Fv=M*a=BL*I, as mass of system is constant, BL values are constant, input current is constant, so
SpeedFor weighing.But when vibrating diaphragm forced vibration to be measured produces resonance, acceleration will be superimposed to be measured on steady state value
The extra acceleration a that vibrating diaphragm forced vibration is producedt=a+a ', wherein atFor total acceleration, a is basic and speed, and a ' is to treat vibration measuring
Coriolis acceleration during membrane resonance.A ' is such as identical with a phase places, then atIncrease, such as opposite in phase, then atReduce.
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