JP2006242536A - Duct-type sound insulation device and duct-type ventilator for building having sound insulating function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a duct-type sound insulation device capable of exercising sound insulation effect of a wide range including intermediate and low frequency areas, though a structure itself is simple without using a sound-deadening material. <P>SOLUTION: A sound inlet port 11 is formed on one end portion of a duct 10 forming a sound propagation passage long in one direction, a sound outlet port 12 is formed on the other end portion of the duct 10, and another inlet port 13 is formed on a position separated from the inlet port by a distance corresponding to a half-wave length of the frequency to be insulated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a duct-type sound insulation device that can be used as a building ventilation facility and a duct-type ventilation device for buildings having a sound insulation function.

  In residential ventilation equipment, the ventilation openings provided on the side walls of the house are directly open to the outside through the duct, so that outside sound enters the room together with air ventilation, and room sound also leaks outside. End up.

  Conventionally, as a countermeasure for silencing at this type of ventilation port, one using a silencing material that absorbs sound in the ventilation port is known. For example, the ventilation apparatus proposed in Japanese Patent No. 3184799 can be cited.

  By the way, in recent years, after new construction or renovation of a house, sick house syndrome that causes poor physical condition or health problems to residents due to volatile chemical substances and mite allergens generated from the building materials in the room has become a problem. As a countermeasure against sick houses, the Building Standards Law was revised in 2002, and the use of chemical substances, which are considered to be the cause, and the installation of mechanical ventilation equipment have become obligatory.

In relation to such countermeasures against sick houses, the importance of sound insulation measures has increased as a matter of course, in ventilation equipment, the ventilation function itself has become increasingly important, as regulations on buildings have been strengthened. Yes. In other words, along with the noise problem that the outside noise enters with the air, which has been a problem in apartment buildings, etc., the problem that the sound inside the room is removed from the ventilation opening and privacy cannot be maintained becomes more obvious. Expected. In particular, in apartment houses, it is necessary to take sound insulation measures for ventilation openings so that neighbors do not have trouble with noise.
Japanese Patent No. 3184799

  However, conventional sound insulation measures at ventilation openings are exclusively made of sound absorbing materials that absorb sound, so road noise, which is a typical noise source, is low even if the effect of reducing high-frequency noise can be obtained. Since the sound range is dominant, it has been pointed out that it is not very effective especially in the middle and low frequency range around 500 Hz, which is a problem in the living environment.

  Therefore, the object of the present invention is to solve the problems of the prior art, and can be effective for sound insulation over a wide range including the mid-low range, while the structure itself is simple without using a silencer. Furthermore, another object of the present invention is to provide a duct-type sound insulation device that can easily control the frequency to be sound-insulated by the interval between introduction ports and the interval between ribs to be arranged.

  Another object of the present invention is to provide a sound insulation function that can be easily installed in a house, and that can achieve both a sound insulation function corresponding to a wide sound range including middle and low sounds and an air ventilation function. The object is to provide a duct type ventilation device for buildings.

  In order to achieve the above object, a duct type sound insulation apparatus according to claim 1 is provided with a sound introduction port at one end of a duct forming a long sound propagation path in one direction and the other end of the duct. A sound lead-out port is provided at the end of the head, and another lead-in port is opened at a position separated from the lead-in port by a distance corresponding to a half wavelength of the frequency to be sound-insulated.

  The duct-type sound insulation device according to claim 2 is provided with a sound introduction port at one end of a duct that forms a long sound propagation path in one direction, and at the other end of the duct. An outlet is provided, and a plurality of ribs having surfaces perpendicular to the longitudinal direction of the duct are arranged in the passage of the duct at predetermined intervals that correlate with frequencies to be sound-insulated.

  According to the second aspect of the present invention, at least two types of ribs having different spacing widths can be combined in the same duct in order to set different frequencies as sound insulation targets.

  According to a fourth aspect of the present invention, there is provided a duct-type ventilator for a building having a sound introduction port that also serves as a ventilation port at one end of a duct that forms a long ventilation passage in one direction communicating with the interior and exterior of the item building. The other end is provided with a sound outlet that also serves as a ventilation port, and another inlet is opened at a position separated from the inlet by a distance corresponding to a half wavelength of the frequency to be sound-insulated. To do.

  Furthermore, the duct type ventilation device for building according to claim 6 is provided with a sound introduction port that also serves as a ventilation port at one end of a duct that forms a long ventilation passage in one direction communicating with the interior and exterior of the building, A sound outlet that also serves as a ventilation port is provided at the other end, and a plurality of ribs having a surface perpendicular to the longitudinal direction of the duct are arranged in the passage of the duct at a predetermined interval that correlates with a frequency to be sound-insulated. It is characterized by this.

  According to the duct type sound insulation apparatus according to the present invention, it is possible to perform sound insulation by targeting a specific frequency to some extent without using a sound deadening material, while the structure itself is simple. Further, by adjusting the interval between the sound introduction port and the rib of the duct, the frequency to be sound-insulated can be controlled, and the effect can be exhibited in a wide range of sound insulation including the mid-low range.

  Further, according to the duct type ventilator having a sound insulation function according to the present invention, the sound insulation function can be easily installed in a house, and is sound-insulated for a specific frequency to some extent or corresponds to a wide sound range including middle and low sounds. And air ventilation function can be achieved.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of a duct type sound insulating device and a building ventilation device having a sound insulating function according to the present invention will be described with reference to the accompanying drawings.
First embodiment
FIG. 1 shows a duct type sound insulation apparatus according to a first embodiment of the present invention. In FIG. 1, reference numeral 10 indicates a main body portion of the duct. The main body 10 of the duct is an elongated duct having a square cross section. A sound inlet 11 is opened at one end of the main body 10, and a sound outlet 12 is opened at the other end. The sound that enters from the inlet 11 propagates through the internal space of the duct as a propagation path and exits from the outlet.

  In the duct type sound insulation device of the present embodiment, another inlet 13 is opened at a predetermined interval from the inlet 11. The position of the introduction port 13 is related to the frequency to be sound-insulated, and is set at a position separated by a distance X corresponding to the half wavelength of the sound of that frequency. For example, when sound insulation is performed aiming at a frequency around 500 Hz, the speed of sound is set to 340 m / s, and the wavelength λ is 340/500 = 68 (cm), which is a half wavelength, and therefore X = 34 cm. .

  Next, the sound insulation effect in the above duct type sound insulation apparatus will be described.

  FIG. 1 shows the sound waveform in the frequency domain aimed at sound insulation in the propagation path of the duct body 10. Since the introduction port 11 and the introduction port 13 are shifted by a distance X corresponding to a half wavelength, the waveform of the sound that has entered from the introduction port 11 and the waveform of the sound that has entered from the introduction port 13 have an inverse phase relationship. , They interfere with each other and cancel each other. Such interference results in sound insulation.

Next, FIG. 2 shows an embodiment in which the duct type sound insulation device as shown in FIG. 1 is incorporated in a ventilation unit of a house.
In FIG. 2, reference numeral 20 indicates an outer wall. Sashes 21a and 21b are provided in the opening of the outer wall. In this embodiment, the main body part 10 of the duct is attached along the upper frames of the sashes 21a and 21b. A space inside the main body 10 of the duct forms a ventilation passage that communicates between the room and the outside. In the duct body 10, the ventilation port 23 at one end opens to the outdoor side, and the ventilation port 24 at the other end opens to the indoor side. An inlet 25 is provided separately from the vent 23, and the position of the inlet 25 is set at a position away from the vent 23 by a distance X corresponding to a half wavelength of the wavelength λ of the frequency to be sound-insulated. ing.

  According to the ventilation unit configured as described above, the ventilation passage of the duct body 10 serves as the original ventilation passage and the sound propagation passage, and enters from the ventilation port 23 and the introduction port 25 together with air. The waveform of the sound is in antiphase, and as a result of mutual cancellation and cancellation, the sound is insulated. In this way, it is possible to configure a ventilation device that has both a ventilation function and a sound insulation function. In addition, the noise X can be reduced by changing the interval X between the ventilation port 23 and the introduction 25 in accordance with the surrounding environment of the house to be attached, etc., and aiming at a frequency that becomes a problem as noise.

  FIG. 2 shows an embodiment in which the duct main body 10 is attached along the upper frame of the sashes 21a and 21b. However, the duct main body 10 may be attached along the vertical frame.

Second embodiment
Next, FIG. 3 shows a duct type sound insulation apparatus according to a second embodiment of the present invention. In FIG. 3, reference numeral 30 indicates the main body of the duct. The main body 30 of the duct is an elongated duct having a square cross section. A sound introduction port 31 is opened at one end of the main body 10, and a sound outlet 32 is opened at the other end. The above is the same as that of the duct of the first embodiment, and the sound that enters from the inlet 31 propagates through the internal space of the duct as a propagation path and exits from the outlet.

  The feature of the duct type sound insulating device according to the second embodiment is that a plurality of ribs 33 having a surface perpendicular to the longitudinal direction of the duct are provided. The interval between the ribs 33 is set as follows.

  That is, FIG. 3A is an example in which the ribs 33 are arranged at regular intervals, and are arranged at predetermined intervals that correlate with the frequencies to be sound-insulated. Specifically, this interval is determined by obtaining an interval at which a sound insulation effect is experimentally obtained for a certain band. For example, it is suitable to measure the sound insulation effect while experimentally changing the interval X in advance, investigate the correlation between the interval X and the frequency having the sound insulation effect, and aim at a specific frequency based on the correlation. The interval may be set.

  FIG. 3B shows a form in which two kinds of intervals X1 and X2 are used in combination as the interval of the ribs 33.

  Next, the sound insulation effect in the above duct type sound insulation apparatus will be described.

  In the duct type sound insulation device according to the second embodiment, the mechanism of the sound insulation effect is not complicated and sufficiently elucidated as compared with the duct type sound insulation device of the first embodiment, but sound is multiplexed on the rib 33. It is considered that the sound-insulating effect is produced by combining the phenomenon of reflection and the phenomenon of sound interference.

  Therefore, hereinafter, as Examples 1 to 5, experimental examples in which the volume reduction is measured at different intervals will be described with reference to the graphs of FIGS. In FIGS. 5 and 6, the horizontal axis represents the frequency, and the vertical axis represents the relative sound pressure level relative to the sound pressure level in the duct without ribs. The more it goes (the negative value increases), the higher the sound reduction effect.

Example 1
In Example 1, an experiment using an actual 1/4 scale model as shown in FIG. 4 was performed. In this model, 16 1m x 2m acrylic plates were combined to create a 2cm thick space, and a duct was placed in the center to establish a two-dimensional sound field. This duct was made of an acrylic plate having a thickness of 2 mm or 3 mm. This duct is equivalent to 10 cm × 10 cm × 180 cm in actual dimensions (hereinafter, the numbers are represented by dimension values in the actual model). The rib interval was 350 mm. In the interior space of the model, a spark discharge pulse sound source and a microphone were arranged 1 m away from the duct. FIG. 5A is a graph showing the measurement results.

Example 2
In Example 2, the same model was measured with a rib interval of 250 mm. FIG. 5B is a graph showing the measurement results.

Example 3
In Example 3, measurement was performed on the same model with a rib interval of 190 mm. FIG. 5C is a graph showing the measurement results.

Example 4
In Example 4, measurement was performed on the same model with a rib interval of 155 mm. FIG. 5D is a graph showing the measurement results.

Example 5
In Example 5, the same model was measured using two types of rib spacing of 155 mm and 220 mm in combination. FIG. 6 is a graph showing the measurement results. In FIG. 6, the measurement results in the case of a single interval of 155 mm and 220 mm are listed for comparison.

Example analysis
5 and 6, arrows 1, 2, and 3 indicate frequency bands in which a sound reduction effect is seen. In each of Examples 1 to 5, a band including a frequency with the rib interval as a half wavelength is indicated by ▲.

  In the case of a single rib interval as in Examples 1 to 4, the lowest frequency (arrow 1) among the frequencies at which the sound reduction effect is observed in each example is substantially the same as the frequency indicated by ▲. From this, it can be seen that there is a correlation between a frequency having a silencing effect and a rib interval having a half wavelength of the frequency. Therefore, the frequency at which the effect appears can be roughly predicted by the rib interval.

  In Examples 1 to 4 in which ribs are arranged at a single interval, the frequency band where the sound reduction effect is seen is narrow. On the other hand, when two types of rib intervals are used together as in the fifth embodiment, it is apparent from FIG. 6 that the frequency at which the sound reduction effect appears is spread over a frequency band of 500 to 1300 Hz. In addition, a sound reduction effect can be obtained even in the mid-low range.

  By using two kinds of rib intervals in this way, the frequency with the sound reduction effect is expanded because each sound reduction effect is superimposed on each adjacent frequency band because each sound reduction effect is superimposed. it is conceivable that.

Next, FIG. 7 shows an embodiment in which the duct type sound insulation device as shown in FIG. 3 is incorporated into a residential ventilation unit.
In this embodiment, the main body portion 40 of the duct is attached along the upper frames of the sashes 21 a and 21 b provided in the opening of the outer wall 20. The space inside the main body portion 40 of the duct forms a ventilation passage that communicates between the room and the outside. In the duct body 40, the ventilation port 42 at one end opens to the outdoor side, and the ventilation port 43 at the other end opens to the indoor side. And the inside of a duct is the same as that of the duct type sound-insulating apparatus of FIG. 3 that the some rib 44 which has a surface perpendicular | vertical to a duct longitudinal direction is provided in the fixed space | interval.

  According to the ventilation unit configured as described above, the ventilation passage 42 of the duct main body portion 10 serves as an original ventilation passage and a sound propagation passage. A sound reduction effect can be obtained by the combined action, and a ventilation device having both a ventilation function and a sound insulation function can be configured without using a silencer as in the prior art.

  FIG. 8 shows an embodiment in which a duct type sound insulating device using two types of rib intervals X1 and X2 is applied to a ventilation unit. The same components as those in FIG. 7 are denoted by the same reference numerals, and the description thereof is omitted.

  According to this, as described above, the frequency at which the sound reduction effect appears can be widened, which is effective for noise countermeasures for the mid-low range.

  As described above, the duct type sound insulating device and the building ventilator having a sound insulating function have been described with reference to the preferred embodiments of the present invention. However, in the building ventilator according to the present invention, the sound deadening material is pasted inside the duct. You may make it use together with material.

The schematic diagram which shows 1st Embodiment of the duct type sound-insulation apparatus by this invention. The figure which shows embodiment which applied the duct type sound-insulation apparatus of FIG. 1 to the ventilation apparatus of a house. The schematic diagram which shows 2nd Embodiment of the duct type sound-insulation apparatus by this invention. Explanatory drawing of the model used for the sound reduction effect measurement of the duct type interruption | blocking apparatus by 2nd Embodiment. The graph which shows the sound reduction measurement result of Examples 1 thru | or 4. 10 is a graph showing the sound reduction measurement result of Example 5. The figure which shows embodiment which applied the duct type sound-insulation apparatus of Fig.3 (a) to the ventilation apparatus of a house. The figure which shows embodiment which applied the duct type sound-insulation apparatus of FIG.3 (b) to the ventilation apparatus of a house.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Duct body part 11 Inlet port 12 Outlet port 13 Inlet port 20 Outer wall 21a, 21b Sash 23 Ventilation port 24 Ventilation port 25 Inlet port 33 Rib

Claims (7)

  A sound inlet is provided at one end of the duct that forms a long sound propagation path in one direction, and a sound outlet is provided at the other end of the duct so that a half wavelength of the frequency to be sound-insulated is obtained. A duct-type sound insulation device, wherein another inlet is opened at a position separated from the inlet by a corresponding distance.   A sound introduction port is provided at one end of a duct that forms a long sound propagation path in one direction, and a sound outlet is provided at the other end of the duct, and has a surface perpendicular to the longitudinal direction of the duct. A duct-type sound insulating device, wherein a plurality of ribs are arranged in the passage of the duct at a predetermined interval that correlates with a frequency to be sound-insulated.   The duct-type sound insulation device according to claim 2, wherein at least two kinds of ribs having different interval widths are combined in the same duct in order to set different frequencies as sound insulation targets.   A sound inlet that also serves as a ventilation port is provided at one end of a duct that forms a long ventilation passage in one direction that communicates with the outside of the building, and a sound outlet that also serves as a ventilation port is provided at the other end. A duct type sound insulation device, wherein another introduction port is opened at a position separated from the introduction port by a distance corresponding to a half wavelength of a frequency to be sound insulation.   The duct-type sound insulation device according to claim 4, wherein the inlet at one end of the duct opens to the outdoor side, and the inlet at the other end opens to the indoor side.   A sound inlet that also serves as a ventilation port is provided at one end of a duct that forms a long ventilation passage in one direction that communicates with the outside of the building, and a sound outlet that also serves as a ventilation port is provided at the other end. A duct-type sound insulation device, wherein a plurality of ribs having a surface perpendicular to the longitudinal direction of the duct are arranged in the passage of the duct at a predetermined interval correlated with a frequency to be sound-insulated.   6. The duct type sound insulation apparatus according to claim 5, wherein at least two types of ribs having different interval widths are combined in the same duct in order to set different frequencies as sound insulation targets.

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