CN214703436U

CN214703436U - Sound absorbing material's testing arrangement

Info

Publication number: CN214703436U
Application number: CN202120433052.3U
Authority: CN
Inventors: 周家为; 洪科; 胡学宝
Original assignee: Hunan Jieli Tai Technology Co ltd
Current assignee: Hunan Jieli Tai Technology Co ltd
Priority date: 2021-02-26
Filing date: 2021-02-26
Publication date: 2021-11-12
Anticipated expiration: 2031-02-26

Abstract

The utility model provides a sound absorbing material's testing arrangement, include: a housing comprising a cavity; an acoustic excitation source disposed within the cavity; a sound collection device disposed within the cavity; a clamp for fixing the sound-absorbing material to be tested in the cavity and positioned between the sound excitation source and the sound collection device; and the audio analyzer is electrically connected with the sound acquisition device. The utility model provides a test device of sound absorbing material can test the sound absorbing material in order to acquire the data relevant with the acoustic absorption coefficient at each desired frequency point to selection for sound absorbing material provides accurate foundation.

Description

Sound absorbing material's testing arrangement

Technical Field

The utility model relates to an acoustics technical field, in particular to sound absorbing material's testing arrangement.

Background

In the technical application of acoustic and electro-acoustic engineering products, the selection of sound-absorbing materials is often involved. Generally, the higher the sound absorption coefficient of the sound absorbing material, the better the sound absorbing effect; on the other hand, the sound absorption coefficients of the materials always correspond to different frequencies, that is, the sound absorption coefficients of the same material to different frequencies are different, so that the sound absorption coefficients of the materials to different frequencies can be accurately judged by testing each frequency point when the sound absorption coefficients of the materials are tested.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a sound absorbing material's testing arrangement, it can test in order to acquire the data relevant with the sound absorption coefficient sound absorbing material.

The utility model provides a test device for sound absorbing material includes: a housing comprising a cavity; an acoustic excitation source disposed within the cavity; a sound collection device disposed within the cavity; a clamp for fixing the sound-absorbing material to be tested in the cavity and positioned between the sound excitation source and the sound collection device; and the audio analyzer is electrically connected with the sound acquisition device.

In an embodiment, the acoustic excitation source comprises a loudspeaker.

In one embodiment, the apparatus for testing a sound absorbing material further comprises a signal generator electrically connected to the source of acoustic excitation.

In one embodiment, the sound collection device is a microphone.

In one embodiment, the cavity is a closed chamber.

In one embodiment, the cavity is circular in cross-section.

In one embodiment, the housing includes a first housing and a second housing connected to each other.

In one embodiment, the first and second housings are secured to each other by fasteners.

In one embodiment, the housing is made of one of metal, bakelite, or acryl.

The utility model provides a test device of sound absorbing material can test the sound absorbing material in order to acquire the data relevant with the acoustic absorption coefficient at each desired frequency point to selection for sound absorbing material provides accurate foundation.

Drawings

Fig. 1 is a schematic view of a test apparatus for a sound-absorbing material according to an embodiment of the present invention.

Fig. 2 is a frequency amplitude curve generated from data obtained by testing the sound absorbing material by the testing device according to the embodiment of the present invention.

Reference numerals:

a housing 10; a cavity 11; a first housing 12; a second housing 13; an acoustic excitation source 20; a sound collection device 30; a jig 40; an audio analyzer 50; a sound absorbing material 60; a fastener 70.

Detailed Description

The following description will be made in conjunction with the accompanying drawings.

Referring to fig. 1 and 2, as a specific example, a test apparatus for a sound-absorbing material according to an embodiment of the present invention includes a housing 10, an acoustic excitation source 20, a sound collection device 30, a jig 40, and an audio analyzer 50. The housing includes a cavity 11, and an acoustic excitation source 20 and a sound collection device 30 are disposed within the cavity 11. The fixture 40 holds a sound-absorbing material 60 to be tested in the cavity 11 between the source of acoustic excitation 20 and the sound collection device 30. The audio analyzer 50 is electrically connected to the sound collection device 30.

With the above configuration, the above test apparatus can be used for testing the sound-absorbing material. In one embodiment, the acoustic excitation source 20 is a speaker that is electrically connected to a standard audio signal generator (e.g., a standard signal generator model Xh-4). The audio signal generator is one of basic equipment in a laboratory, can generate three waveforms of 0.1-20000 Hz sine waves, rectangular waves, triangular waves and the like, and the acoustic excitation source converts the audio signals output by the standard audio signal generator into audio frequency for output. It can be understood that the standard audio signal generator is not limited to the foregoing, and other existing audio signal generators, such as an audio signal generator based on an 8051F330 single chip microcomputer and an STM32F429 chip, may be selected according to actual needs. These audio signal generators are already known and can be obtained through existing public channels, and are not described herein.

In one embodiment, the sound collection device 30 is a microphone (e.g., an AP550-A type microphone). In the present embodiment, the acoustic excitation source 20 and the sound collection device 30 are located near both ends of the cavity 11, respectively. Acoustic excitation source 20 and/or sound collection device 30

In one embodiment, the cavity 11 is a closed cavity, for example, two ends of the housing 10 are respectively fixed with end caps, so that two open ends of the cavity 11 can be covered to form a closed cavity.

In one embodiment, the cavity 11 is circular in cross-section, and after reading this specification, it will be appreciated by those skilled in the art that the housing 10 functions to focus the sound emitted from the acoustic excitation source 20 onto the sound-absorbing material 60 being measured, thereby avoiding the interference of external sound. Therefore, the cross section of the cavity 11 is not limited thereto, and may be changed according to actual needs, for example, the cross section of the cavity 11 may be square or other suitable shapes.

In one embodiment, the housing 10 includes a first housing 12 and a second housing 13 that are connected to each other. For example, the first housing 12 and the second housing 13 are both circular tubes having a diameter of 200mm and a wall thickness of 5 mm. The first housing 12 and the second housing 13 are fixed to each other by a fastener 70 (e.g., a screw). The housing 10 is made of one material of metal, bakelite or acryl.

In one embodiment, the clamp 40 is annular and has an outer diameter equal to or slightly less than the inner diameter of the cavity 11. In this manner, the jig 40 can be properly received in the cavity 11. In one embodiment, the outer side of the clamp 40 is formed with a receiving groove that is close at both ends in the circumferential direction but does not meet together (in which case the clamp 40 is divided into two separate rings). In this manner, the sheet-loaded material to be tested can be inserted into the receiving groove and can be received into the cavity 11 following the jig 40.

The audio analyzer 50 is connected to the sound collection device 30, and the audio analyzer 50 is configured to obtain the audio signal output by the sound collection device 30 and display the spectrum information of the audio signal. In the present embodiment, the audio analyzer 50 is an AP550 type audio analyzer, but is not limited thereto, and other existing audio analyzers may be used as needed.

When the test device is used, before the clamp 40 and the sound-absorbing material to be tested 60 are placed in the cavity 11, the sound excitation source 20 sends out a frequency sweeping signal with the frequency of 20-20000 Hz and the power of 1-3W under the control of the audio generator. The sound collection means 30 feed the collected signal to the audio analyzer 50, and the audio analyzer 50 now records a frequency amplitude curve without any attenuation, see curve 1 in fig. 2. The jig 40 and the sound-absorbing material 60 to be tested are then placed in the cavity 11 with the sound-absorbing material 60 to be tested between the sound excitation source 20 and the sound collection device 30, so that the sound outputted from the sound excitation source 20 must pass through the sound-absorbing material 60 before being collected by the sound collection device 30. The acoustic excitation source 20 emits a frequency sweep signal with a frequency of 20 to 20000Hz again under the control of the audio generator, and the sound collection device 30 sends the received frequency sweep signal attenuated by the material to be tested to the audio analyzer 50, and analyzes and displays a frequency amplitude curve, see curve 2 in fig. 2. As can be seen from the difference between the two curves in fig. 2, the sound absorption coefficient of the sound absorbing material 60 increases with the increase of the frequency, i.e. the sound with higher frequency is absorbed by the sound absorbing material 60 more, for example, the sound with 20KHz is almost completely absorbed, and the sound absorption coefficient reaches 0.9 or more, but the sound absorption effect of the material with low frequency is not ideal.

From the above, the testing device can test the sound-absorbing material to obtain the data related to the sound-absorbing coefficient of the sound-absorbing material, so as to provide an accurate basis for the selection of the sound-absorbing material.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A test device for a sound absorbing material, comprising:

a housing comprising a cavity;

an acoustic excitation source disposed within the cavity;

a sound collection device disposed within the cavity;

a clamp for fixing the sound-absorbing material to be tested in the cavity and positioned between the sound excitation source and the sound collection device;

and the audio analyzer is electrically connected with the sound acquisition device.

2. The apparatus for testing a sound absorbing material of claim 1, wherein the acoustic excitation source includes a speaker.

3. The apparatus for testing a sound absorbing material of claim 2, further comprising a signal generator electrically connected to the source of acoustic excitation.

4. The apparatus for testing a sound-absorbing material as claimed in claim 1, wherein the sound collection means is a microphone.

5. The test device for a sound-absorbing material according to any one of claims 1 to 4, wherein the cavity is a closed chamber.

6. The test device for a sound-absorbing material according to any one of claims 1 to 4, wherein the cross section of the cavity is circular.

7. The test device for a sound-absorbing material according to any one of claims 1 to 4, wherein the casing comprises a first casing and a second casing which are connected to each other.

8. The apparatus for testing a sound-absorbing material according to claim 7, wherein the first casing and the second casing are fixed to each other by a fastening member.

9. The test device for a sound-absorbing material according to any one of claims 1 to 4, wherein the housing is made of one of metal, bakelite, and acryl.