JP2019109430A - Acoustic characteristic measurement system and acoustic characteristic measurement method - Google Patents

Abstract

To enable measuring acoustic characteristic similar to when the shield member is used without using a structure in which the shield member is actually installed, and quantitatively measuring acoustic characteristic of the shield member itself.SOLUTION: The acoustic characteristic measurement system includes a first chamber 1 containing a sound producing device 5, a second chamber 2 containing an acoustic measurement device 6 and adjacent to the first chamber 1, a partition wall part 3 shared by the first and second chambers 1, 2, an opening part 4 provided at the partition wall part 3, and a holding mechanism 8 which holds an object to be measured S at a position facing the opening 4 in the first and second chambers 1, 2. The acoustic measurement device 6 can measure selectively at a plurality of measurement points at different vertical positions, a plurality of measurement points at different horizontal positions, or a plurality of measurement points at different vertical positions and a plurality of measurement points at different horizontal positions, and the holding mechanism can selectively hold the object to be measured at a plurality of holding positions at different vertical positions.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an acoustic characteristic measurement system and an acoustic characteristic measurement method for measuring acoustic characteristics of an object to be measured.

  When sound insulation is required at an opening (window) provided in a building, a housing or the like, as disclosed in Patent Document 1, a shielding member (for example, sound insulation or sound absorption) covering the opening Curtain) is placed. The shielding member covering the opening has different acoustic characteristics such as sound insulation and sound absorption depending on its material, so the acoustic characteristics are actually measured as disclosed in Patent Documents 2 and 3, and the acoustics of each shielding member are We are looking for characteristics. And the shielding member which has an acoustic characteristic according to a use is selected and used.

According to Patent Document 2, different curtains are attached to two openings provided on one wall in the room, the sounding body is disposed in the room, and the sound transmitted through each curtain is directly heard by the ear and each curtain is A method of determining sound isolation performance is disclosed.
In Patent Document 3, a sound insulation curtain is installed on the indoor side at a distance from an opening of a structure such as a house, an office, or a factory, and a sound absorbing curtain is installed between the opening and the sound insulation curtain. A soundproofing test is disclosed in which the microphones placed in the room and received by the microphones installed indoors and outdoors are received.

Japanese Utility Model Publication No. 50-129416 Unexamined-Japanese-Patent No. 2002-297148 JP-A-53-146452

  In the method disclosed in Patent Document 2, the soundproofing effect is determined by the examiner hearing the sounds of music, tracks of highways, and sounds of railways, insects, and roars. This method is aimed to know the sensory soundproofing effect on human auditory sense, and also to compare the soundproofing effects of multiple curtains. That is, it is not possible to quantitatively measure and determine the acoustic characteristics of one shielding member itself. The situations in which the method of Patent Document 2 is effective are limited, and the method is not a method for obtaining the acoustic characteristics of the shielding member itself as data that can be used generally. In addition, in the method of Patent Document 2, only relative evaluation of two curtains to be directly compared can be performed, and a test result based on a common criterion can be obtained so that a large number of various shielding members can be compared on data. I can not do it.

  According to the method disclosed in Patent Document 3, since a sound insulation curtain and a sound absorption curtain are arranged and tested at the opening of a construction of a house, an office, a factory, etc. which is actually used, the soundproof according to the practice is realized. You can ask for the effect. However, it is often difficult to conduct a soundproofing test on curtains using constructions of houses, offices, factories, etc. that are actually used as in the method of Patent Document 3. Therefore, it is desirable to test acoustic characteristics in a test environment that simulates the actual use environment. However, even if a test room imitating the actual use environment is provided and the method of Patent Document 3 is applied, measurement results of the environment according to the actual use condition can not be obtained, and acoustics at the time of use of each curtain It may not always be sufficient as a method of measuring the characteristics.

  Therefore, the object of the present invention is to make it possible to measure similar acoustic characteristics at the time of use of the shielding member without using the construction itself in which the shielding member is actually installed, and to quantify the acoustic characteristics of the shielding member itself An acoustic characteristic measurement system and an acoustic characteristic measurement method that can be determined by

  The acoustic characteristic measurement system for measuring the acoustic characteristic of the object to be measured according to the present invention comprises a first chamber in which the sound producing device is disposed, and an acoustic measurement device disposed in the interior, the second chamber being adjacent to the first chamber. , A partition which is a common wall of the first chamber and the second chamber, an opening which is provided in the partition and communicates the first chamber with the second chamber, and And a holding mechanism for holding the object to be measured at a position opposite to the opening in the second chamber or the second chamber. The acoustic measurement apparatus selectively measures a plurality of measurement points whose positions in the vertical direction are different, or selectively measures a plurality of measurement points whose positions in the horizontal direction differ, or a plurality of measurement points whose positions in the vertical direction differ The acoustic measurement can be selectively performed at a plurality of measurement points at different positions, and the holding mechanism can selectively hold the object at a plurality of holding positions at different vertical positions.

  According to the acoustic characteristic measurement system and the acoustic characteristic measurement method of the present invention, it is possible to measure similar acoustic characteristics at the time of use of the shielding member without using the construction itself on which the shielding member is actually installed, and moreover shielding The acoustic characteristics of the member itself can be determined quantitatively.

It is a schematic diagram which shows the acoustic characteristic measuring system of one Embodiment of this invention. It is an enlarged view of a part of inner wall of the 2nd room of an acoustic characteristic measuring system shown in Drawing 1. It is a perspective view which shows the opening part of the partition part of the acoustic characteristic measuring system shown in FIG. It is a perspective view which shows the state in which the flame | frame was attached to the opening part shown in FIG. It is a perspective view which shows the state in which the curtain rail was attached to the flame | frame shown in FIG. It is a perspective view which shows the state in which the curtain was attached to the curtain rail shown in FIG. It is a front view which shows the measurement point of the acoustic characteristic in the curtain installation state shown in FIG. 6, and a graph which shows a measurement result. It is a graph which shows each measurement result regarding the sound of each frequency in a part of measurement point of the acoustic characteristic in the curtain installation state shown in FIG.

Hereinafter, embodiments of the present invention will be described.
The present invention provides an acoustic characteristic measurement system and an acoustic characteristic measurement method for measuring acoustic characteristics (for example, sound insulation) of an object to be measured (for example, a shielding member S such as an elastically deformable flexible curtain). . One embodiment of the acoustic characteristic measurement system of the present invention is schematically shown in FIG. The acoustic characteristic measurement system has two chambers, ie, a reverberation chamber 1 which is a first chamber, and a semi-anechoic chamber 2 or an anechoic chamber which is a second chamber. The reverberation chamber 1 and the semi-anechoic chamber 2 are adjacent and share a part of the wall (partition 3). The reverberation chamber 1 has an inner wall made of a reverberation plate such as a metal plate. The semi-anisotropic chamber 2 has a sound absorbing structure on the inner wall, for example, a protrusion 15 (see FIG. 2) made of a sound absorbing material is provided on almost the entire inner wall, but no protrusion is provided on the floor surface. A chamber in which all the inner walls including the floor surface have a sound absorbing structure is called an anechoic chamber. The second chamber of the present invention may be a semi-anechoic chamber 2 or an anechoic chamber.

  As shown in FIG. 3, an opening 4 is provided in a partition 3 which is a wall shared by the reverberation chamber 1 and the semi-anechoic chamber 2, and the inside of the reverberation chamber 1 is provided with the opening 4. And the interior of the semi-anechoic chamber 2 are in communication. The opening 4 preferably has a size equal to or larger than a window of a building or a housing where the shielding member S, which is an object to be measured, is actually installed. As one example, the size of the preferred opening 4 is 200 mm × 200 mm. However, in the configuration example shown in FIGS. 1 to 6, the opening 4 smaller than 200 mm × 200 mm is provided. For example, a speaker 5 is disposed inside the reverberation chamber 1 as a sound producing device. An acoustic measurement device including a microphone 6 which is a sound receiving unit, for example, and a support member 14 of the microphone 6 is disposed inside the semi-anechoic chamber 2. Then, inside the reverberation chamber 1 or the semi-anechoic chamber 2, a holding mechanism is provided at a position facing the opening 4 to hold the shielding member S as the object to be measured in the same form as the actual installation form There is. A specific example of the holding mechanism includes a frame 7 attached to the opening 4 and a holding member of the shielding member S attached to the frame 7 (a specific example is a curtain rail 8). Although not shown, when a window glass is fitted to a window such as a building or a housing where the shielding member S is actually used, a similar glass plate is fitted to the frame 7 to form an actual building. It is preferable to make it substantially the same as the window of the housing or the case.

  The acoustic measurement device and the holding mechanism of the present embodiment will be described in more detail. In the present embodiment, as shown in FIG. 3, an opening that simulates a window of a building or a casing in which the shielding member S is actually installed in the partition 3 shared by the reverberation chamber 1 and the semi-anechoic chamber 2. 4 is provided. Then, as shown in FIG. 4, the frame 7 is attached to the outer periphery of the opening 4. The frame 7 has a guide portion 9 provided with an elongated hole 9 a extending in the vertical direction. And as shown in FIG. 5, the curtain rail 8 which is a holding member of a shielding member (for example, curtain S) is attached to this guide part 9. As shown in FIG. The frame 7 and the curtain rail 8 are included in the holding mechanism. Specifically, the screw 10 is passed through an L-shaped protruding piece 8a provided on the curtain rail 8, and the screw 10 is passed through the long hole 9a and then tightened to a nut (not shown), thereby the screw 10 and the nut The curtain rail 8 is held on the frame 7 by firmly holding the projecting piece 8 a and the guide portion 9 with each other. With such a configuration, the vertical position of the curtain rail 8 can be changed by loosening the screw 10 from the nut and moving it up and down along the long hole 9a and screwing it again into the nut. Thus, the holding mechanism of the present embodiment can arbitrarily change the position of the shielding member (curtain S) relative to the opening 4 and the frame 7 in the vertical direction.

  Further, the support member 14 for supporting the microphone 6 of the acoustic measurement device of the present invention shown in FIG. 1 can move up and down along the rail 11, and also horizontally along the rail 13 (a position facing the partition 3a. The arm is movable in the left and right direction as viewed from the side, and the positions of the support member 14 and the microphone 6 in the vertical and horizontal directions are fixed by tightening a screw (not shown). Since this configuration is simplified in FIG. 1, the screw is loosened, the support member 14 is moved vertically and horizontally along the rails 11 and 13, and the screw is tightened again. The position of the microphone 6 in the vertical direction and the horizontal direction can be changed. Thus, the sound measurement device of the present embodiment can arbitrarily change the positions of the microphone 6 relative to the opening 4 and the rail 11 in the vertical direction and the horizontal direction.

  As described above, in the present embodiment, by moving the microphone 6 of the acoustic measurement device by the arm-shaped support member 14, it is possible to selectively perform acoustic measurement at a plurality of measurement points whose positions in the vertical and horizontal directions are different. It is. In addition, the curtain rail 8 which is a holding member moves up and down along the long hole 9a, and the shielding member (curtain S) can be selectively held at a plurality of holding positions where the positions in the vertical direction are different.

  A method of measuring acoustic characteristics (for example, sound insulation) of the object S using the acoustic characteristic measurement system will be described. First, in a state where the curtain S, which is a shielding member, is not disposed, the speaker 5 in the reverberation chamber 1 generates a sound, and the sound measurement device including the microphone 6 of the semi-anechoic chamber 2 measures volume or sound pressure level. This measurement data is later used to determine the acoustic characteristics (for example, sound insulation) of the curtain S.

  Then, the screw 10 passing through the projecting piece 8a of the curtain rail 8, which is a holding member of the curtain S, is disposed at an arbitrary vertical position and tightened to a nut (not shown) while passing through the long hole 9a. Thereby, the curtain rail 8 is fixed at an arbitrary position in the vertical direction. As shown in FIG. 6, a curtain (shielding member) S which is an object to be measured is attached to the curtain rail 8. The attachment of the curtain S to the curtain rail 8 may be before or after fixing the curtain rail 8. Thus, the curtain S is disposed at an arbitrary position relative to the opening 4 in the vertical direction. Specifically, when the curtain S is actually mounted and used so as to cover a window of a building or a housing, the distance by which the upper portion of the curtain S protrudes upward from the upper end of the window, and the acoustic characteristic measurement system The distance between the upper portion of the curtain S and the distance projecting upward from the upper end of the opening 4 is as close as possible. Similarly, when the curtain S is actually mounted and used to cover a window of a building or a housing, the distance by which the lower part of the curtain S projects downward from the lower end of the window and the curtain S in the acoustic characteristic measurement system Of the lower part of the lower end of the opening 4 from the lower end of the opening 4 as closely as possible. Thus, the position of the curtain S with respect to the opening 4 is determined.

  Then, the sound generated from the speaker 5 in the reverberation chamber 1, transmitted through the object S to be measured disposed in the opening 4 and transmitted to the semi-echo chamber 2 is an acoustic including the microphone 6 of the semi-echo chamber 2 Measure with a measuring device. At this time, in the present embodiment, the positions of the microphone 6 in the vertical and horizontal directions are changed, and sound measurement (measurement of volume or sound pressure level, etc.) is performed at a plurality of measurement points. Specifically, the arm-shaped support member 14 is moved up and down along the rail 11 to arrange the microphone 6 at a position near the lower end of the opening 4 and facing the lower part of the curtain S, Make a measurement. Further, the support member 14 is moved in the vertical direction along the rail 11 to arrange the microphone 6 at a position near the center of the opening 4 and facing the center of the curtain S to perform acoustic measurement. Further, the support member 14 is moved vertically along the rail 11 to arrange the microphone 6 at a position near the upper end of the opening 4 and above the upper portion of the curtain S. That is, the microphone 6 is disposed at or near the position facing the curtain rail 8 to perform acoustic measurement. Also, for example, from the position where the microphone 6 is near the center of the opening 4 and faces the center of the curtain S, the support member 14 is moved in the horizontal direction (left and right direction) along the rail 13 The microphone 6 is disposed at a position to the left of the unit to perform acoustic measurement. Furthermore, the support member 14 is moved in the horizontal direction (left and right direction) along the rail 13 to arrange the microphone 6 at a position on the right side of the right end of the curtain S, and the acoustic measurement is performed. As described above, in the present embodiment, the microphones 6 are arranged at at least five locations in the vertical and horizontal directions without changing the position of the speaker 5 in the reverberation chamber 1, and acoustic measurement is performed at at least five measurement points. Do. Thus, the acoustic characteristics (for example, sound insulation) of the curtain S can be determined by subtracting the data measured in a state in which the curtain S is not disposed in advance from each data measured at each measurement point, in other words, Soundproofing effect is required.

  The technical significance of the acoustic characteristic measurement system and the acoustic characteristic measurement method will be described. The acoustic measurement performed by disposing the microphone 6 near the center of the opening 4 and facing the center of the curtain S is a measurement process similar to that generally performed in conventional acoustic measurement. It is. In this embodiment, in addition to this conventional measurement process, the microphone 6 is disposed at a position below the lower end of the opening 4 and facing the lower part of the curtain S to perform acoustic measurement. That is, it is possible to measure whether the sound is transmitted to the outside of the curtain S around the lower end of the curtain S. In particular, by adjusting the vertical position of the curtain rail 8, the lower part of the curtain S is the same as the distance by which the lower part of the curtain S protrudes downward from the lower end of the window at the actual installation of the curtain S. The sound measurement is performed in a state of projecting below the lower end. As described above, in the present embodiment, it is possible to quantitatively determine the wraparound of sound from the lower end of the curtain S, which has not been measured conventionally, as numerical data. Moreover, since the positional relationship between the lower end of the opening 4 and the lower end of the curtain S in the vertical direction matches as much as possible with the environment actually installed, similar acoustic characteristics can be obtained during actual use.

In addition, in the present embodiment, the microphone 6 is disposed at a position above the upper end of the opening 4 and above the top of the curtain S, that is, at or near the position facing the curtain rail 8; Make an acoustic measurement. Thereby, it is possible to measure the sound wrap around from the upper end of the curtain S and the sound passing through the gap between the curtain S and the curtain rail 8 or the frame 7 and the curtain rail 8 itself.
Further, in the present embodiment, the microphone 6 is also moved in the left-right direction, arranged at a position to the left of the left end of the curtain S and at a position to the right of the right end of the curtain S. Make a measurement. As a result, it is possible to measure and analyze the sound wrap around from the left end or the right end of the curtain S in the same manner as the sound wrap around from the upper end or the lower end of the curtain S described above.

  Heretofore, since the sound was mainly measured only at one measurement point near the center of the curtain S and the center of the opening 4, it was possible to know the acoustic characteristics (for example, sound insulation) depending on the material of the curtain S itself. . However, sound leakage due to the installation configuration of the curtain S, in particular, the sound passing through the gap between the curtain S and the curtain rail 8 or the frame 7 as the holding member is not measured. Therefore, the sound leakage at the time of the actual installation of the curtain S may be largely different from the predicted level. On the other hand, according to the present embodiment, in addition to knowing the acoustic characteristics depending on the material of the curtain S itself by measuring the sound at the center of the curtain S and near the center of the opening 4, the lower end, the upper end, the left end or the curtain In order to measure the sound wrap around from the right end and the sound passing through the gap between the curtain S and the curtain rail 8 and the frame 7 as its holding members, the sound in a similar state when the curtain S is actually used Characteristics can be determined. Accordingly, the acoustic characteristics of the curtain S can be determined more finely and accurately than before, and the material of the curtain can be appropriately selected according to the application, and the installation form, that is, the selection of the curtain rail 8 which is a holding member The selection of the installation position in the vertical direction or the horizontal direction can be appropriately implemented and determined according to the required acoustic characteristic. Moreover, since numerical data such as volume and sound pressure level can be obtained without depending on the test person's hearing, quantitative acoustic characteristics (for example, sound insulation) based on a common standard are required. Therefore, many different shielding members and their installation forms can be easily compared on the data. In the present embodiment, the curtain rail 8 can be removed and easily replaced with another curtain rail 8 by loosening and removing the screw 10 passing through the projecting piece 8 a of the curtain rail 8. Therefore, it is possible to easily select the curtain rail 8 of more appropriate material and shape according to the measurement result particularly at the upper measurement point. As described above, in the acoustic characteristic measurement system, the curtain rail 8 (holding member) can be easily replaced, and acoustic characteristics (for example, sound insulation) including not only the curtain S but also the curtain rail 8 as the holding member are obtained. Thus, contributing to the selection of a more appropriate sound insulation mechanism is impossible in Patent Documents 1 to 3 and is now possible in the present invention.

  In the configuration shown in FIG. 1, the frame 7 and the curtain rail 8 are attached to the surface of the bulkhead 3 on the side of the semi-animous chamber 2, and the curtain S is placed in the semi-animous chamber 2 and measurement is performed. . On the other hand, although not shown, a modification is also possible in which the frame 7 and the curtain rail 8 are attached to the surface of the bulkhead 3 on the reverberation chamber 1 side, and the curtain S is disposed in the reverberation chamber 1 and measurement is performed. It is. Also in this modification, since the microphone 6 is disposed in the semi-anechoic chamber 2, the reverberation chamber 1 is transmitted through the curtain S disposed in the opening 4 as in the acoustic characteristic measurement system shown in FIG. The sound transmitted to the semi-anechoic chamber 2 can be measured, and the acoustic characteristics (for example, sound insulation) of the curtain S can be measured.

  A more specific embodiment of the acoustic characteristic measurement system of the present invention will be described. The reverberation chamber 1 shown in FIG. 1 is a square of 2.4 m × 2.4 m in floor surface, the height of the partition 3 is 2.2 m, and the height of the wall on the opposite side of the partition 3 is 2.m. It is 1m. The inner wall surface of the reverberation chamber 1 is all made of iron plate. The semi-anechoic chamber 2 is a square having a floor surface of 2.1 m × 2.4 m, and the height of the wall portion opposite to the partition 3 is 2.0 m. Wedge-like projections 15 made of glass wool are formed on the inner wall surface of the semi-anchorous chamber 2 except the floor surface of the semi-anchorous chamber 2 and the mounting portion of the frame 7 without a gap (see FIG. 2). The opening 4 provided in the partition 3 has a dimension of 200 mm × 200 mm. In the frame 7, a glass plate (not shown) similar to a window glass provided in a window of a building or a housing in which the shielding member S is actually disposed is fitted. In the reverberation chamber 1, speakers 5 are placed on the floor in the vicinity of the partition 3 and in the vicinity of the opposite wall. On the other hand, a microphone 6 is disposed in the semi-anechoic chamber 2 toward the opening 4. The speaker 5 is connected to a sound source (not shown) and can be sounded. The microphone 6 is connected to an analyzer (not shown), which analyzes the sound recorded by the microphone 6.

Using such acoustics measuring system, first, sound from the speaker 5 of the reverberation chamber 1 in a state that does not place the shielding member S, the sound pressure level SPL ₀ of sound recorded by the microphone 6 of the semi-anechoic chamber 2 Ask for

Next, a shielding member (for example, a curtain S) which is an object to be measured is disposed so as to cover the opening 4. Specifically, as described above, the screw 10 passing through the projecting piece 8a of the curtain rail 8 is disposed at an arbitrary vertical position and tightened to a nut (not shown) while passing through the long hole 9a. Thus, the curtain rail 8 is fixed at an arbitrary position in the vertical direction, and the curtain (shielding member) S as the object to be measured is attached to the curtain rail 8. Therefore, the sound transmitted from the speaker 5 in the reverberation chamber 1 to the semi-anechoic chamber 2 through the object S to be measured disposed in the opening 4 is received by the microphone 6 in the semi-anechoic chamber 2 Do. At this time, the sound pressure level SPL _{1 received} by the microphone 6 is measured, and the analyzer calculates the sound interception volume as an insertion loss from the following equation.
Insertion loss [dB] = SPL ₀ [dB]-SPL ₁ [dB]

Thus, the determination of the sound shielding volume is performed at each of a plurality of measurement points. Specifically, in the example shown in FIG. 7, the sound pressure level in the state where the shielding member S is not disposed at 11 measurement points, and two curtains S (first and second curtains made of different materials) The sound pressure level at the time of installing. The first curtain is a lace curtain with an areal density (weight per unit area) of 0.17 kg / m ² , and the second curtain is a draped curtain with an areal density of 0.35 kg / m ² . In FIG. 7A, 11 measurement points are indicated by a distance above the lower end of the curtain S from the lower end of the curtain S as a reference (0 mm). Accordingly, in the vertical direction, -20 mm is a position below the lower end of the curtain S and the lower end of the opening 4, 0 mm, 50 mm and 100 mm is a position below the curtain S and below the lower end of the opening 4, 320 mm And 335 mm and 350 mm are the positions opposed to the central part of the curtain S and the central part of the opening 4, 430 mm is the upper part of the opening S opposite to the upper part of the curtain S, 505 mm and 520 mm and 535 mm is the curtain S And a position above the upper end of the opening 4. Thus, as shown in FIG. 7 (B), the sound volume of the sound pressure level is determined for each of the 11 measurement points when the first curtain and the second curtain are installed. There is. From the difference between the sound pressure level and the sound pressure level when the curtain is not installed, the sound interception volume of the first curtain and the second curtain is obtained. As a result, the shielding volume of the first curtain is about 2.5 to 8 dB, and the shielding volume of the second curtain is about 3 to 11 dB. It has been found that the second curtain having such a high surface density has higher sound insulation than the first curtain having a low surface density. The difference between the sound insulation of the first curtain and the sound insulation of the second curtain is large near the center of the curtain S and the opening 4. However, the difference between the sound insulation of the first curtain and the sound insulation of the second curtain is small at the upper and lower portions of the curtain S and above the upper and lower ends of the curtain S. Therefore, the sound insulation in the vicinity of the center of the curtain S and the opening 4 is not so important, or in the case where other sound insulation mechanisms are used in combination, it is important to prevent sound leakage at the upper and lower portions of the curtain S. In some cases, a low first density curtain may be sufficient.

  In addition, sound insulation to sounds of various frequencies at two measurement points, specifically at the center (350 mm) of the curtain S and the opening 4 and above the upper end of the curtain S and the upper end of the opening 4 (520 mm) Is shown in FIG. According to this, the sound insulation of the sound in a wide range is generally low at the upper end (520 mm) above the upper end of the curtain S and the upper end of the opening 4. And the sound insulation of the first curtain (difference in sound pressure level with the curtain not installed) is 5.6 dB on average, the sound insulation of the second curtain is 6.3 dB on average, and the difference between the two is small. On the other hand, in the center (350 mm) of the curtain S and the opening 4, the sound insulation of particularly high frequency sound is excellent, and the sound insulation of the first curtain is 18.6 dB on average, and the second curtain Sound insulation is 21.4 dB on average, and the difference between the two is relatively large. In addition, according to the present embodiment, it is possible to quantitatively evaluate the average increase (the amount of improvement of sound leakage from the upper end of the curtain S) of the difference in the sound pressure level (sound insulation) by installing the curtain S. . That is, when the first curtain is installed, it can be said that the sound leakage preventing effect from the vicinity of the upper end of the curtain S is 18.6−5.6 = 13.0 dB. On the other hand, when the second curtain is installed, it can be said that the sound leakage preventing effect from near the upper end of the curtain S is 21.4−6.3 = 15.1 dB. As described above, the second curtain having a large area density is more effective for sound leakage from the upper end of the curtain S than the first curtain having a small area density.

In this way, according to the present invention, appropriate measurement of the acoustic characteristics (for example, sound insulation) of the object to be measured can be performed. Since sound can be measured at a plurality of measurement points at different vertical positions, sound wraparound from the upper end or the lower end of the object to be measured can be quantitatively determined as numerical data. Therefore, it is possible to know not only the material of the object to be measured but also the influence of the installation form on the acoustic characteristics, which contributes to the realization of the appropriate installation according to the application. Furthermore, since the holding member of the object to be measured can be moved up and down, the acoustic characteristic can be obtained in the installation form of the object to be measured in actual use. Further, since the holding member can be easily replaced, it is possible to easily select not only the object to be measured but also the holding member of an appropriate material or shape according to the application.
7 and 8 show the results of acoustic measurement and analysis at a plurality of measurement points where the vertical position of the object to be measured (curtain S) is different, but the horizontal position of the object to be measured is different. More preferably, acoustic measurement and analysis are performed at multiple measurement points. The present invention is configured to be able to selectively perform acoustic measurement and analysis at a plurality of measurement points at different vertical positions, and to be able to selectively perform acoustic measurement and analysis at a plurality of measurement points at different horizontal positions. And any of the configurations capable of selectively performing acoustic measurement and analysis at a plurality of measurement points having different vertical positions and a plurality of measurement points having different horizontal positions. The sound measurement device has a configuration that can appropriately move the sound receiving unit according to each configuration.

  The present invention is not limited to the sound insulation, and various acoustic characteristics such as the tendency of sound transmission according to each frequency can be obtained. For detailed experimental conditions and the like of acoustic measurement, known methods, for example, methods described in Japanese Industrial Standards (JIS A1416, A1428, A1441) can be applied.

DESCRIPTION OF SYMBOLS 1 reverberation room 2 half anechoic room 3 partition part 4 opening part 5 speaker (sound generator)
6 Microphone (sound measurement device, sound receiving unit)
7 Frame 8 Curtain rail (holding member)
8a Protruding piece 9 Guide portion 9a Long hole 10 Screw 11 Rail 13 Rail 14 Support member 15 Protrusion S Measured object (shielding member, curtain)

Claims (16)

An acoustic characteristic measurement system for measuring acoustic characteristics of an object to be measured, comprising:
A first chamber in which the sound producing device is disposed, and a second chamber in which the acoustic measurement device is disposed and adjacent to the first chamber, and the first chamber and the second chamber are shared A partition portion which is a wall portion, an opening portion provided in the partition portion to communicate the first chamber and the second chamber, and the inside of the first chamber or the second chamber A holding mechanism for holding the object to be measured at a position facing the opening,
The acoustic measurement apparatus selectively and / or selectively at a plurality of measurement points at different vertical positions or at a plurality of measurement points at different horizontal positions and / or at different left and right positions. It is possible to measure acoustically selectively at multiple measurement points with different directional positions,
The acoustic characteristic measurement system according to claim 1, wherein the holding mechanism is capable of selectively holding the object to be measured at a plurality of holding positions different in vertical position.   The sound measurement apparatus has a sound receiving unit, and the sound receiving unit can move to a plurality of measurement points at different vertical positions, or can move to a plurality of measurement points at different horizontal positions. The acoustic characteristic measurement system according to claim 1, wherein the acoustic characteristic measurement system is movable between a plurality of measurement points whose positions in the vertical direction are different and a plurality of measurement points whose positions in the horizontal direction are different.   The plurality of measurement points include a position facing the center of the opening, a position below the lower end of the opening, and a position above the upper end of the opening in the vertical direction. The acoustic characteristic measurement system according to 2.   The plurality of measurement points include a position facing the center of the opening, a position to the left of the left end of the opening, and a position to the right of the right end of the opening in the left-right direction. The acoustic characteristic measurement system according to claim 2 or 3.   The sound receiving unit is a microphone, and the sound measurement device supports the microphone and sets the microphone to a plurality of measurement points different in the vertical position, or a plurality of measurement points different in the horizontal position, or The acoustic characteristic measurement system according to any one of claims 2 to 4, further comprising a support member that moves a plurality of measurement points having different vertical positions and a plurality of measurement points having different horizontal positions.   The acoustic characteristic measurement system according to any one of claims 1 to 5, wherein the object to be measured is a curtain, and the holding mechanism includes a curtain rail.   The acoustic characteristic measurement system according to claim 6, wherein the curtain rail is vertically movable.   The acoustic characteristic measurement system according to any one of claims 1 to 7, wherein the first chamber is a reverberation chamber and the second chamber is an anechoic chamber or a semi-anechoic chamber. A method of measuring acoustic characteristics of an object to be measured comprising:
Provided in a first chamber, a second chamber adjacent to the first chamber, a partition which is a common wall of the first chamber and the second chamber, and the partition Using an opening for communicating the first chamber with the second chamber;
The object to be measured is held at a position facing the opening in the first chamber or the second chamber, and sound generation is performed in the first chamber to perform acoustic measurement in the second chamber. Determine the acoustic characteristics of the object by
The acoustic measurement is performed at a plurality of measurement points at different vertical positions, at a plurality of measurement points at different horizontal positions, or at a plurality of measurement points at different vertical positions and at different positions in the horizontal direction. A method of measuring acoustic characteristics, which is performed at each measurement point.   The plurality of measurement points include a position facing the center of the opening, a position below the lower end of the opening, and a position above the upper end of the opening in the vertical direction. The acoustic characteristic measuring method as described in 9.   The plurality of measurement points include a position facing the center of the opening, a position to the left of the left end of the opening, and a position to the right of the right end of the opening in the left-right direction. The acoustic characteristic measurement method according to claim 9 or 10.   The sound measurement is performed using a microphone, and the plurality of measurement points are moved by moving the microphone in the vertical direction, in the lateral direction, or in the vertical direction and the lateral direction using the support member for supporting the microphone. The acoustic characteristic measurement method according to any one of claims 9 to 11, wherein the acoustic measurement is performed.   The acoustic characteristic measurement method according to any one of claims 9 to 12, wherein the acoustic measurement is performed after adjusting the vertical position of the object to be measured.   14. The acoustic characteristic measurement method according to claim 13, wherein the object to be measured is a curtain, and the vertical position of the object to be measured is adjusted by moving a curtain rail holding the curtain in the vertical direction.   The acoustic characteristic measurement method according to any one of claims 9 to 14, wherein the first chamber is a reverberation chamber and the second chamber is an anechoic chamber or a semi-anechoic chamber. The acoustic characteristic measurement method according to any one of claims 9 to 15, wherein the sound measurement is performed by emitting a sound having a frequency of 400 Hz or more and 10000 Hz or less from the sound generation device.