CN208780600U - A kind of sound resistance test device of sound-absorbing material - Google Patents
A kind of sound resistance test device of sound-absorbing material Download PDFInfo
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- CN208780600U CN208780600U CN201821564790.6U CN201821564790U CN208780600U CN 208780600 U CN208780600 U CN 208780600U CN 201821564790 U CN201821564790 U CN 201821564790U CN 208780600 U CN208780600 U CN 208780600U
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Abstract
A kind of sound resistance test device of sound-absorbing material, including vacuum pump, flow metering pin valve, mass flowmenter, differential pressure pick-up and test fixture, the vacuum pump and test fixture pass through piping connection, the test fixture is equipped with the test mouth for placing sound-absorbing material to be measured, and the test mouth is connected to the connecting line of vacuum pump；The flow metering pin valve and mass flowmenter are set on the connecting pipeline between vacuum pump and test fixture, and mass flowmenter is set between flow metering pin valve and test fixture；Pipeline connection in the test port and test fixture of the differential pressure pick-up, another test port are connected to ambient atmosphere.It can be realized the resistive energy of sound-absorbing material sound of online quickly test acoustic product.
Description
Technical field
The utility model relates to a kind of test devices of sound-absorbing material, more particularly to one kind to be used for mobile phone speaker, Mike
The sound of the sound-absorbing materials such as the inside acoustical cottons of the electronic products such as wind, dust-proof screen cloth hinders test device.
Background technique
Sound resistance (flow resistance) test of the sound-absorbing material (porous material) of acoustic product, it is former to be all based on impedance tube test at present
Reason carries out sound absorption and testing impedance.This test is generally basede on laboratory installation progress, shows to produce to obtain an impedance value
The characteristic of product.But this laboratory test device and method are applied on acoustic product production line then extremely inconvenient, one side
Cause producing line deployment complicated, on the other hand can seriously affect the production efficiency of producing line, thus be generally only applicable to type inspection and
The occasions such as sampling inspection.But for electronic product higher for quality requirements, manufacture is larger, and product quantity is more,
It is usually produced by fast pipeline, and the requirement of performance and quality is also higher and higher, each component includes acoustic element
It is required to directly carry out quick on-line checking in the production line, is just able to satisfy its higher yields requirement, guarantees to produce
Quality.
Patent document CN102680376A discloses a kind of ventilative test device, to test the gas permeability of acoustical cotton.It is wrapped
Clamping tooling, flowmeter and air pressure regulator are included, the air pressure regulator connects to power supply, the flowmeter and air pressure regulator
Connection, is provided with air circuit breaker between flowmeter and clamping tooling.As long as acoustical cotton is placed on clamping by the ventilative test device
The bubbles volume in the unit time by acoustical cotton can be easily measured in tooling, use is more convenient, and cost is relatively low.But it is only
Walk through test can be carried out by flowmeter, and cannot exclude the influence of external environment variation, test result is inaccurate.
Utility model content
In view of above situation, the utility model proposes a kind of sounds of sound-absorbing material to hinder test device, can be realized online fast
The resistive energy of sound-absorbing material sound of speed test acoustic product.
A kind of sound resistance test device of sound-absorbing material, including a test chamber, it is to be measured for placing that the test chamber is equipped with one
The test mouth of sound-absorbing material, the test chamber are also connected to one negative pressure device of setting and negative pressure test pipeline；The negative pressure test
Pipeline is equipped with flow regulator and flow measurement device；Further, the test chamber is also connected to one differential pressure of setting and examines
Device is surveyed, another detection mouth of the differential pressure measuring device is connected to ambient atmosphere.
Preferably, a negative pressure preset is equipped between the negative pressure device and negative pressure test pipeline.
Preferably, the negative pressure preset includes a pressure reducing valve connecting with negative pressure device and pressure test dress
It sets, negative pressure preset further includes the device of control negative pressure test pipeline on-off.
Preferably, a kind of sound-absorbing material sound hinder test device, including vacuum pump, flow metering pin valve, mass flowmenter,
Differential pressure pick-up and test fixture, the vacuum pump and test fixture are equipped with and are put by piping connection, the test fixture
The test mouth of sound-absorbing material to be measured is set, the test mouth is connected to the connecting line of vacuum pump；The flow metering pin valve and matter
Amount flowmeter is set on the connecting pipeline between vacuum pump and test fixture, and mass flowmenter is set to flow metering pin valve and survey
It tries between jig；Pipeline connection in one test port of the differential pressure pick-up and test fixture, another test port with
Ambient atmosphere connection.The test fixture is mainly used for setting test mouth to place sound-absorbing material to be measured, is equipped in test fixture
Test chamber, the test chamber be only functionally for, can be the cavity being arranged in test fixture, Jin Ershe in structure
The one end for emptying chamber is connected to test mouth, and the connecting line between the other end and test mouth and vacuum pump tests pipeline connection；
But in practical application, it can will test the i.e. test pipeline of the connecting line between mouth and vacuum pump and directly connect with the test mouth
It is logical, then structurally, the test pipeline portions in the test fixture are test chamber functionally.
Preferably, on the pipeline between the vacuum pump and flow metering pin valve, vacuum regulator, pressure are successively arranged
Sensor and solenoid valve.It is pre-adjusted loine pressure in the initial stage of test, is also convenient for subsequent adjustment flow metering pin valve.
Since rear road test component precision is higher, it has been pre-adjusted loine pressure before solenoid valve unlatching, it can be to avoid unlatching electromagnetism
Adjustable range is excessive after valve, to improve efficiency.
The sound of sound-absorbing material according to the present utility model hinders test method, and step is,
Sound-absorbing material to be measured is placed in a closed cavity or tests the air entry of pipeline；
The closed cavity or testing tube are made by negative pressure mode from the closed cavity or the other end for testing pipeline
Pressure and external atmosphere pressure in road form pressure differential Δ P；
It measures the pressure differential Δ P and the closed cavity or tests the flow U of the fluid in pipeline；
It calculates the closed cavity or tests the flow velocity u of the fluid in pipeline, calculating formula are as follows: u=U/S, wherein S is to be measured
The sectional area that sound-absorbing material passes through in the air entry of the closed cavity or test pipeline for fluid；
Calculate sound-absorbing material to be measured than flow resistance r, calculating formula are as follows: r=Δ P/u.
Further, before sound-absorbing material to be measured to be placed in a closed cavity or tests the air entry of pipeline, presetting institute
It states closed cavity or tests the fluid flow in pipeline, step is,
According to sound-absorbing material to be measured the closed cavity or test sectional area S that the air entry of pipeline passes through for fluid and
Preset reference line flow velocity u calculates the closed cavity or tests the reference flow U1 of pipeline, calculating formula are as follows: U1=uS；
It adjusts the closed cavity or tests the fluid flow U in pipeline, make in the closed cavity or test pipeline
Fluid flow U is equal with the reference flow U1.
Further, before sound-absorbing material to be measured to be placed in a closed cavity or tests the air entry of pipeline, presetting institute
It states closed cavity or tests the negative pressure in pipeline, step is,
The closed cavity or testing tube are made by negative pressure mode from the closed cavity or the other end for testing pipeline
Pressure in road is between -2~-5kpa.
According to the sound of the sound-absorbing material of the application resistance test device, the accurate differential pressure pick-up of differential pressure pick-up use/
Little differential pressure sensor/differential pressure pickup, flow metering pin valve use delicate flow metering pin valve, and the range of mass flowmenter is
5LPM, the range of differential pressure pick-up are 200pa.Laminar flow shape is in by the fluid that delicate flow metering pin valve ensures to flow through product
State acquires the air pressure under laminar condition compared with atmospheric pressure using differential pressure pick-up, and then it is (more to calculate acquisition sound-absorbing material to be measured
Porous materials) sound hinder (than flow resistance).
It is further preferred that the sound of the sound resistance test device of above-mentioned sound-absorbing material hinders test method, it is,
1, the sectional area of sound-absorbing material to be measured is set first；The sectional area described herein for setting sound-absorbing material to be measured,
It is that the area for the test mouth that test fixture is connected to ambient atmosphere is arranged, that is, sound-absorbing material (porous material) is placed in
When on the test mouth of test fixture, the sectional area of the tested part of sound-absorbing material.The test open area of test fixture, can be pre-
The nozzle of different specification size is first set, is replaced as needed in test；It is also possible to preset adjustable test
Mouthful, such as the cover board that setting is moved or rotated on test mouth；By determining the test open area of test fixture, that is, can determine
Tested product, that is, sound-absorbing material to be measured is tested the sectional area of part.On the other hand, described to set sound-absorbing material to be measured
Sectional area also refers to and acquiring each sensing data by computer system and when calculating ratio flow resistance r, first will known to or really
The sectional area of fixed sound-absorbing material to be measured is arranged in calculation procedure, so as to subsequent calculating.Although can be by manually reading biography
Sensor data simultaneously calculate in turn, but consider the efficiency of on-line checking, generally also need to execute related operation by computing system.
2, it keeps solenoid valve to close, open vacuum pump and adjusts vacuum regulator, make the pipe between vacuum pump and solenoid valve
Road pressure is between -2~-5kpa；Line pressure is obtained by pressure sensor；
3, the reference flow U1 of pipeline is calculated according to the sectional area of setting and reference line flow velocity 0.1m/S；Reference line flow velocity
It is set as 0.1m/S, is to be tested lower than 0.1m/s, pressure in 0.1~200pa using line flow velocity.It is subsequent be put into it is tested
When product, that is, sound-absorbing material of examination, due to its inhibition, line flow velocity will be less than 0.1m/s, at this point for the more of most of type
Porous materials especially for the inside acoustical cotton and dust-proof screen cloth for mobile phone speaker, microphone products for, flow through
Fluid will be in laminar condition, can be derived that reliable test result.
Calculating formula are as follows: U1=u1S；Wherein, U1: flow, m3/s；U1: reference line flow velocity, m/s；S: sectional area, m2。
4, opens solenoid valve makes the test pipeline connection between vacuum pump and test fixture；
5, adjustment precision flow metering pin valve makes the flow U tested in pipeline reach calculated pipeline reference flow U1；
The measured value for testing flow U in pipeline is obtained by mass flowmenter；
6, sound-absorbing material to be measured is placed in the test mouth of test fixture；
7, sound-absorbing material to be measured hinders air to enter test pipeline, so that the pressure of pipeline cavity and the external world in test fixture
Atmospheric pressure forms pressure differential Δ P, and the pressure difference value is obtained by differential pressure pick-up；
8, sound-absorbing material to be measured makes the flow velocity u for the fluid tested in pipeline generate variation after hindering air, according to quality
The flow U that flow measurement obtains calculates flow velocity u；
Calculating formula are as follows: u=U/S；Wherein, U: the flow value obtained by mass flowmenter real-time monitoring, m3/s；S: section
Product, m2。
9, according to above-mentioned results of measuring calculate sound-absorbing material to be measured than flow resistance r；
Calculating formula are as follows: r=Δ P/u；Wherein, r: sound-absorbing material is than flow resistance, rayls (Pas/m)；Δ P: test chamber and big
Pressure difference between gas, Pa；U: the flow velocity obtained in real time, m/s.
Take the utility model proposes technology after, technical solution according to the present utility model, have it is below
The utility model has the advantages that
1) the resistive energy of sound-absorbing material sound of online quickly test acoustic product, and testing efficiency and test essence be can be realized
It spends higher.The sound resistance for being particularly suitable for the inside acoustical cotton, dust-proof screen cloth of the electronic products such as mobile phone speaker, microphone is surveyed
Examination quickly can test and tell the sound resistance numerical value of product, greatly improve the yield of finished product.
2) the unstable influence to test result of atmospheric pressure can be excluded using differential pressure pick-up；Pass through delicate flow tune
The fluid line flow velocity tested in pipeline can be adjusted to the laminar condition of 0.1m/S by markingoff pin valve, it is ensured that pass through product in test
Fluid air pressure change is by stable capture；It is easy to using the pressure that negative pressure test can will transmit through sound-absorbing material (porous material)
Control is in the range of 0.1~200pa and is in laminar condition.
3) test speed is fast, tests product about 3~6S time, is suitble to online quick and mass test；Test
Apparatus structure is simple, convenient for safeguarding and maintenance；Compact, convenient for being used in electronics producing line.
Detailed description of the invention
Fig. 1 is to hinder test device connection schematic diagram according to the sound of the sound-absorbing material of the application.
Specific embodiment
The utility model is described in further detail below in conjunction with the embodiment that attached drawing provides.Described implementation
Example includes the various details for helping to understand, but they can only be counted as illustratively, be a part of the utility model
Embodiment, instead of all the embodiments.Meanwhile in order to keep specification more clear succinct, will omit pair it is well known that function
The detailed description that can and construct.
Unless otherwise defined, the technical term or scientific term used herein is should be in the utility model fields
The ordinary meaning that personage with general technical ability is understood."upper" described herein, "lower" or " top ", " lower section " are these
The upper and lower relation that application attached drawing is substantially shown.When placement status changes, such as when overturning, corresponding positional relationship
It should convert therewith to understand or implement the technical solution of the application.
As shown in Figure 1, a kind of sound of sound-absorbing material hinders test device, including vacuum pump 1, flow metering pin valve 2, quality stream
Meter 3, differential pressure pick-up 4 and test fixture 5, the vacuum pump 1 and test fixture 5 are controlled by piping connection, the test
Tool 5 is equipped with the test mouth for placing sound-absorbing material to be measured, and the test mouth is connected to the connecting line of vacuum pump 1；The flow
Metering pin valve 2 and mass flowmenter 3 are set on the connecting pipeline between vacuum pump 1 and test fixture 5, and mass flowmenter 3 is set
Between flow metering pin valve 2 and test fixture 5；Pipeline in the test port and test fixture 5 of the differential pressure pick-up 4
Connection, another test port are connected to ambient atmosphere.The test fixture 5 is mainly used for setting test mouth to place suction to be measured
Sound material, is equipped with test chamber in test fixture 5, the test chamber be only functionally for, can be setting in structure and exist
Cavity in test fixture 5, and then one end that cavity is arranged is connected to test mouth, between the other end and test mouth and vacuum pump 1
Connecting line i.e. test pipeline connection；But in practical application, it can will test the connecting line between mouth and vacuum pump 1 and survey
Test tube road is directly connected to the test mouth, then structurally, the test pipeline portions in the test fixture
It is test chamber functionally.
Further, on the pipeline between the vacuum pump 1 and flow metering pin valve 2, it is successively arranged vacuum regulator
11, pressure sensor 12 and solenoid valve 13.It is pre-adjusted loine pressure in the initial stage of test, is also convenient for subsequent adjustment stream
Measure metering pin valve 2.Since rear road test component precision is higher, it has been pre-adjusted loine pressure before the unlatching of solenoid valve 13, it can
It is excessive to avoid adjustable range after opens solenoid valve 13, to improve efficiency.
According to the sound of the sound-absorbing material of the application resistance test device, the accurate differential pressure pick-up of the use of differential pressure pick-up 4/
Little differential pressure sensor/differential pressure pickup, flow metering pin valve 2 use delicate flow metering pin valve, and the range of mass flowmenter 3 is
5LPM, the range of differential pressure pick-up 4 are 200pa.Laminar flow is in by the fluid that delicate flow metering pin valve 2 ensures to flow through product
State acquires the air pressure under laminar condition compared with atmospheric pressure using differential pressure pick-up 4, and then calculates and obtain sound-absorbing material to be measured
The sound of (porous material) hinders (than flow resistance).
Using the method for above-mentioned sound resistance test device test sound-absorbing material sound resistance, include the following steps.
1, the sectional area of sound-absorbing material to be measured is set first.The sectional area described herein for setting sound-absorbing material to be measured,
It is that the area for the test mouth that test fixture 5 is connected to ambient atmosphere is arranged, that is, sound-absorbing material (porous material) is placed
When on the test mouth of test fixture, the sectional area of the tested part of sound-absorbing material.The test open area of test fixture 5, can
To preset the nozzle of different specification size, replaced as needed in test；It is also possible to preset adjustable
Test mouth, such as the cover board that setting is moved or rotated on test mouth；By determining the test open area of test fixture 5, i.e.,
It can determine that tested product sound-absorbing material i.e. to be measured is tested the sectional area of part.On the other hand, described to set sound-absorbing to be measured
The sectional area of material also refers to and acquiring each sensing data by computer system and when calculating ratio flow resistance r, first will known to
Or the sectional area of fixed sound-absorbing material to be measured is arranged in calculation procedure, so as to subsequent calculating.Although can be by artificial
It reads sensing data and calculates in turn, but consider the efficiency of on-line checking, generally also need to execute correlation by computing system
Operation.
2, it keeps solenoid valve 13 to close, open vacuum pump 1 and adjusts vacuum regulator 11, make vacuum pump 1 and solenoid valve 13
Between loine pressure be between -2~-5kpa；Line pressure is obtained by pressure sensor 12.
3, the reference flow U1 of pipeline is calculated according to the sectional area of setting and reference line flow velocity 0.1m/S；Reference line flow velocity
It is set as 0.1m/S, is to be tested lower than 0.1m/s, pressure in 0.1~200pa using line flow velocity.It is subsequent be put into it is tested
When product, that is, sound-absorbing material of examination, due to its inhibition, line flow velocity will be less than 0.1m/s, at this point for the more of most of type
Porous materials especially for the inside acoustical cotton and dust-proof screen cloth for mobile phone speaker, microphone products for, flow through
Fluid will be in laminar condition, can be derived that reliable test result.
Calculating formula are as follows: U1=u1S；Wherein, U1: flow, m3/s；U1: reference line flow velocity, m/s；S: sectional area, m2。
4, opens solenoid valve 13 make the test pipeline connection between vacuum pump 1 and test fixture 5.
5, adjustment precision flow metering pin valve 2 makes the flow U tested in pipeline reach calculated pipeline reference flow
U1；The measured value of flow U is obtained by mass flowmenter 3 in test pipeline.
6, sound-absorbing material to be measured is placed in the test mouth of test fixture 5.
7, sound-absorbing material to be measured hinders air to enter test pipeline, so that the pressure of pipeline cavity and outer in test fixture 5
Boundary's atmospheric pressure forms pressure differential Δ P, and the pressure difference value is obtained by differential pressure pick-up 4.
8, sound-absorbing material to be measured makes the flow velocity u for the fluid tested in pipeline generate variation after hindering air, according to quality
The flow U that flowmeter 3 measures calculates flow velocity u；
Calculating formula are as follows: u=U/S；Wherein, U: the flow value obtained by 3 real-time monitoring of mass flowmenter, m3/s；S: it cuts
Area, m2。
9, according to above-mentioned results of measuring calculate sound-absorbing material to be measured than flow resistance r；
Calculating formula are as follows: r=Δ P/u；Wherein, r: sound-absorbing material is than flow resistance, rayls (Pas/m)；Δ P: test chamber and big
Pressure difference between gas, Pa；U: the flow velocity obtained in real time, m/s.
Test device is hindered according to the sound of the sound-absorbing material of the application, passes through the lines such as mass flowmenter 3 and flow metering pin valve 2
Current velocity controller come realize sound-absorbing material (porous material) flow through liquid retaining layer stream mode in order to by test；And pass through difference
Pressure mode calculates the sound resistance of sound-absorbing material (porous material)；The pressure control of 0.1pa precision is realized in the way of negative pressure.?
When being detected on production line, previously according to the application sound resistance test method regulate device after, only need to be by sound-absorbing to be measured
Material is placed in the test mouth of test fixture 5, and test can be completed, test result is calculated.Convenient for high-volume sound-absorbing to be measured
Material is carried out continuously test, can be realized the resistive energy of sound-absorbing material sound of online quickly test acoustic product, and testing efficiency
It is higher with measuring accuracy.It is particularly suitable for the inside acoustical cottons of the electronic products such as mobile phone speaker, microphone, dust-proof screen cloth
Sound resistance test quickly can test and tell the sound resistance numerical value of product, greatly improve the yield of finished product.
Test device is hindered according to the sound of the sound-absorbing material of the application, compared with existing measuring technology scheme, is had following
Beneficial effect.
The unstable influence to test result of atmospheric pressure can be excluded using differential pressure pick-up；It is adjusted by delicate flow
The fluid line flow velocity tested in pipeline can be adjusted to the laminar condition of 0.1m/S by needle-valve, it is ensured that pass through the stream of product in test
Body air pressure change is by stable capture；It is easy to control using the pressure that negative pressure test can will transmit through sound-absorbing material (porous material)
System is in the range of 0.1~200pa and is in laminar condition.
On the other hand, test speed is fast, tests product about 3~6S time, and online quick and mass is suitble to survey
Examination；Test device structure is simple, convenient for safeguarding and maintenance；Compact, convenient for being used in electronics producing line.
Claims (5)
1. a kind of sound hinders test device, which is characterized in that including a test chamber, the test chamber is equipped with one for placing suction to be measured
The test mouth of sound material, the test chamber are also connected to one negative pressure device of setting and negative pressure test pipeline；The negative pressure testing tube
Road is equipped with flow regulator and flow measurement device；Further, the test chamber is also connected to one differential pressure measuring of setting
Another detection mouth of device, the differential pressure measuring device is connected to ambient atmosphere.
2. a kind of sound according to claim 1 hinders test device, which is characterized in that the negative pressure device and the negative pressure are surveyed
A negative pressure preset is equipped between test tube road.
3. a kind of sound according to claim 2 hinders test device, which is characterized in that the negative pressure preset include one with
The pressure reducing valve and a pressure test device of negative pressure device connection, negative pressure preset further include that control negative pressure test pipeline is logical
Disconnected device.
4. a kind of sound according to any one of claim 1 to 3 hinders test device, which is characterized in that including vacuum pump, stream
Metering pin valve, mass flowmenter, differential pressure pick-up and test fixture, the vacuum pump and test fixture is measured to connect by pipeline
It connects, the test fixture is equipped with the test mouth for placing sound-absorbing material to be measured, the connecting line company of the test mouth and vacuum pump
It is logical；The flow metering pin valve and mass flowmenter are set on the connecting pipeline between vacuum pump and test fixture, quality stream
Meter is set between flow metering pin valve and test fixture；A test port and test fixture inner tube for the differential pressure pick-up
Road connection, another test port are connected to ambient atmosphere.
5. a kind of sound according to claim 4 hinders test device, which is characterized in that in the vacuum pump and flow metering needle
On pipeline between valve, it is successively arranged vacuum regulator, pressure sensor and solenoid valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201821564790.6U CN208780600U (en) | 2018-09-26 | 2018-09-26 | A kind of sound resistance test device of sound-absorbing material |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201821564790.6U CN208780600U (en) | 2018-09-26 | 2018-09-26 | A kind of sound resistance test device of sound-absorbing material |
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| CN208780600U true CN208780600U (en) | 2019-04-23 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108982332A (en) * | 2018-09-26 | 2018-12-11 | 常州北埠电子技术有限公司 | A kind of the sound resistance test method and its test device of sound-absorbing material |
| CN110879138A (en) * | 2019-11-14 | 2020-03-13 | 歌尔股份有限公司 | Dust screen assembly detection equipment and detection method |
-
2018
- 2018-09-26 CN CN201821564790.6U patent/CN208780600U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108982332A (en) * | 2018-09-26 | 2018-12-11 | 常州北埠电子技术有限公司 | A kind of the sound resistance test method and its test device of sound-absorbing material |
| CN110879138A (en) * | 2019-11-14 | 2020-03-13 | 歌尔股份有限公司 | Dust screen assembly detection equipment and detection method |
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