JP2018053708A - Sound insulation louver - Google Patents

Abstract

Provided is a sound insulation louver 1 capable of reducing costs, dealing with noise from various directions, and ensuring sufficient sound insulation performance. A sound insulation louver 1 according to the present invention is a sound insulation louver 1 in which a plurality of louver blade members 3 are continuously arranged, and a resonator 10 having a slit-like opening is disposed on the louver blade member. It is characterized by being. [Selection] Figure 3

Description

  The present invention relates to a sound insulation louver that can ensure air permeability, has excellent design properties, and can ensure sufficient sound insulation performance.

  When equipment such as an air conditioner outdoor unit is installed on the building roof or on the ground, a blindfold wall is installed to hide the equipment from the surroundings. As the blindfold wall, a louver wall is preferred because of the necessity of ensuring air permeability and design requirements.

  On the other hand, in order to prevent noise generated from the equipment from propagating to the surroundings, high sound insulation performance is required for the blindfolded wall. Conventionally, soundproof louvers have been proposed so far in order to reduce the noise transmitted through the gaps in the louver wall.

For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2013-213334) discloses a louver body 11 provided with an opening 13 for inserting the sound absorbing material 50 on the opposite surface of the decorative surface 12, and an opening of the louver body 11. And a sound absorbing louver provided with a cover material 30 covering 13.
JP 2013-213334 A

  A conventional sound absorbing louver is mainly composed of a louver body, a sound absorbing material such as glass wool, and a pressing member for the sound absorbing material, and a member for joining them is also required, resulting in an increase in the number of members and a complicated structure.

  The increase in the number of members and the complexity of the structure lead to an increase in cost due to an increase in man-hours in manufacturing, transportation, and construction in addition to an increase in the cost of the members themselves.

  As described above, the conventional sound absorbing louvers proposed for satisfying the air permeability, the design, and the sound insulation performance have a problem that many of them are expensive due to the complexity of the structure.

  In addition, conventional sound absorption louvers are generally designed to absorb noise effectively at a specific noise incident angle, but noise is generally incident on the louver wall from various directions. There is also a problem in that it may not be possible to ensure sound insulation performance.

  This invention solves the above-mentioned problem, the sound insulation louver according to the present invention is a sound insulation louver in which a plurality of louver blade members are continuously arranged, and a resonator having a slit-like opening, It is arranged on the louver blade member.

  The sound insulating louver according to the present invention is characterized in that a resonator is disposed on each of two main surfaces of the louver blade member.

  Moreover, the sound insulation louver according to the present invention is characterized in that the slit-like openings of the resonators of the adjacent louver blade members are arranged to face each other.

  In the sound insulation louver according to the present invention, the resonator is embedded in the louver blade member.

  The sound insulation louver according to the present invention is characterized in that the resonator is divided into a plurality of sections by a partition plate member.

  In the sound insulation louver according to the present invention, a resonator having a slit-like opening having an acoustic impedance ratio of 0 is arranged in the propagation path 100. According to such a sound insulation louver according to the present invention, the structure is simple. Therefore, costs associated with increases in manufacturing, transportation, and construction man-hours can be reduced.

  In addition, according to the sound insulation louver according to the present invention, it is possible to cope with noise from various directions and to ensure sufficient sound insulation performance.

It is a figure explaining the principle of the sound insulation louver 1 which concerns on embodiment of this invention. It is a figure explaining the resonator 10 used for the sound insulation louver 1 which concerns on embodiment of this invention. It is a figure which shows the sound insulation louver 1 which concerns on embodiment of this invention. It is a figure explaining the example of a manufacturing process of the resonator 10 used for the sound insulation louver 1 which concerns on embodiment of this invention. It is a figure which shows the example of application to the propagation path 100 of the sound insulation louver 1 which concerns on other embodiment of this invention. It is a figure explaining the resonator 10 used for the sound insulation louver 1 which concerns on other embodiment of this invention. It is sectional drawing of the resonator 10 applied to the propagation path 100 of the sound insulation louver 1 which concerns on other embodiment of this invention. It is sectional drawing of the resonator 10 applied to the propagation path 100 of the sound insulation louver 1 which concerns on other embodiment of this invention. It is a figure which shows the sound insulation louver 1 which concerns on other embodiment of this invention. It is a figure explaining the resonator 10 used for the sound insulation louver 1 which concerns on other embodiment of this invention. It is a figure which shows a part of three types of louver wall made into the calculation object of numerical calculation. It is a figure which shows the frequency characteristic of the insertion loss of each louver wall.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the principle of the noise reduction method employed by the sound insulation louver 1 according to the present invention will be described. FIG. 1 is a view for explaining the principle of a sound insulation louver 1 according to an embodiment of the present invention.

  FIG. 1A is a perspective view of a louver. The louver is configured by continuously arranging a plurality of louver blade members 3. Although this example shows the case where the louver blade members 3 are arranged with a predetermined space in the vertical direction, the louvers may be configured by arranging the louver blade members 3 in the horizontal direction.

  The louver blade member 3 has two main surfaces 4 and 5. The main surface 4 (main surface 5) of one louver blade member 3 and the main surface 5 (main surface) of the louver blade member 3 adjacent thereto. The space between the surface 4) is an air flow path, a light optical path, or a sound propagation path. Such a space is referred to as a propagation path 100.

  Here, FIG. 1B is a diagram showing only the inner space in the propagation path 100 as described above. When noise propagates through the propagation path 100, which is the space between the louver blade members 3, when the dimensional cross section of the propagation path 100 (the plane perpendicular to the noise propagation direction) is less than half of the noise wavelength, the noise Propagates one-dimensionally as a plane wave in the pipe.

  Hereinafter, in the propagation path 100 according to the embodiment of the present specification, a noise source exists on the upstream side (inside surrounded by the sound insulation louver 1), and noise from the noise source is propagated downstream (outside). This will be described as an example. In addition, although the description will be made on the assumption that the longitudinal direction of the propagation path 100 is installed in the horizontal direction, the installation method of the propagation path 100 is not limited to such an example.

  In the propagation path 100 of the sound insulation louver 1 according to the present invention, it is assumed that the two principal surfaces 4 and 5 that face each other at the top and bottom of the propagation path 100 are in an acoustically “soft” state. As shown in FIG. 1B, when the surfaces facing each other in the propagation path 100 are acoustically “soft”, that is, when the acoustic impedance ratio Z on the surfaces of the main surface 4 and the main surface 5 is 0, the upstream It is known that noise propagated from the side is reflected upstream and does not propagate downstream.

  In the present embodiment, the description is based on an example in which two opposing surfaces having an acoustic impedance ratio Z of 0 on the surfaces of the main surface 4 and the main surface 5 are opposed in the vertical direction. Two opposing wall surfaces having an acoustic impedance ratio Z of 0 may be opposed in the horizontal direction.

  The conventional technology (for example, the technology described in Japanese Patent No. 383263 and Japanese Patent No. 5454369) uses a frequency at which the tube length of the acoustic tube is equal to a quarter wavelength and an odd multiple of the frequency. It is utilized that the acoustic impedance ratio Z at the tube opening becomes zero.

  On the other hand, the sound insulation louver 1 according to the present invention uses a resonator 10 in which a resonance phenomenon occurs due to a slit structure having a cavity sealed behind as shown in FIG. FIG. 2A is a perspective view of the resonator 10. FIG. 2B is a cross-sectional view of the slit-like opening 50 of the resonator 10 of FIG.

  As shown in FIG. 2, the resonator 10 used in the sound insulation louver 1 according to the present invention basically includes a quadrangular prism-shaped housing 40 whose inner space is hollow. On one surface of the casing 40 constituting the resonator 10, a longitudinal slit-shaped opening 50, and a partition wall 60 that is disposed on both sides of the slit-shaped opening 50 and extends to a space inside the resonator 10. It is characterized by having. Here, each dimension of the resonator 10 is represented by a symbol shown in FIG. Note that the one surface of the housing 40 in which the slit-shaped opening 50 is formed and the partition wall 60 are orthogonal to each other.

  When each dimension of the resonator 10 is sufficiently small with respect to the wavelength, the acoustic impedance ratio Z in the slit-shaped opening 50 can be obtained by the following equation (1).

ただし、ｆは騒音の周波数、ｃは音速、ρは媒質（空気）密度を表す。また、Ｖ_nは、スリット状開口部５０と隔壁部６０とで囲まれた、図２（Ｂ）の斜線部以外の空間の体積で、開口端補正を考慮して次式（２）で計算される。なお、式（２）における[ ]内の第２項が、開口端補正に関連する項である。また、図２（Ｂ）で斜線部の空間は、共鳴器として機能する共鳴器１０の空気層に相当する。

However, f represents the frequency of noise, c represents the speed of sound, and ρ represents the medium (air) density. V _n is the volume of the space surrounded by the slit-shaped opening 50 and the partition wall 60 except for the hatched portion in FIG. 2B, and is calculated by the following equation (2) in consideration of opening end correction. Is done. Note that the second term in [] in Equation (2) is a term related to opening end correction. In FIG. 2B, the hatched space corresponds to the air layer of the resonator 10 functioning as a resonator.

また、Ｖは共鳴器１０の空洞部の体積（空気層の体積）で、次式（３）で計算される。

V is the volume of the cavity of the resonator 10 (volume of the air layer), and is calculated by the following equation (3).

また、Ｓは、スリット状開口部５０（スリット開口）の面積で、次式（４）で計算される。

S is the area of the slit-like opening 50 (slit opening) and is calculated by the following equation (4).

式（１）の右辺第１項のｒは、共鳴器として機能する共鳴器１０の隔壁部６０表面と空気の間に生じる摩擦などの音響抵抗である。隔壁部６０を金属など表面が平滑な材料で構成する場合、音響抵抗ｒは極めて小さな値となり、次式を満足する共鳴周波数ｆにおいてスリット状開口部５０の開口における音響インピーダンス比Ｚがほぼ０となる。

R in the first term on the right side of Equation (1) is an acoustic resistance such as friction generated between the surface of the partition wall 60 of the resonator 10 functioning as a resonator and the air. When the partition wall 60 is made of a material having a smooth surface such as a metal, the acoustic resistance r has an extremely small value, and the acoustic impedance ratio Z at the opening of the slit-shaped opening 50 is substantially 0 at the resonance frequency f that satisfies the following equation. Become.

このような共鳴器として機能する、２つの共鳴器１０を、図３に示すように、伝搬路１００の上下の内壁１０５に沿って対向配置すると、上記の周波数ｆにおいては対向するスリット部が音響的に“ソフト”な状態となり、上流側から伝搬してきた周波数ｆの騒音は上流側へ反射され下流側に伝搬しない。図３は本発明の実施形態に係る遮音ルーバー１を示す図であり、本発明の実施形態に係る遮音ルーバー１を、伝搬路１００の長手方向（或いは、スリット状開口部５０の長手方向）を垂直に切って見た断面図である。

When two resonators 10 functioning as such resonators are disposed opposite to each other along the upper and lower inner walls 105 of the propagation path 100 as shown in FIG. Therefore, the noise of the frequency f propagated from the upstream side is reflected to the upstream side and does not propagate to the downstream side. FIG. 3 is a view showing the sound insulation louver 1 according to the embodiment of the present invention. The sound insulation louver 1 according to the embodiment of the present invention is arranged in the longitudinal direction of the propagation path 100 (or the longitudinal direction of the slit-like opening 50). It is sectional drawing seen perpendicularly.

  According to the sound insulation louver 1 of the propagation path 100 as shown in FIG. 3, the acoustic impedance ratio at the slit-like opening 50 of the resonator 10 facing at the resonance frequency of the resonator 10 becomes substantially 0, and the indoor side (upstream side) ) Is reflected to the outdoor side and does not propagate to the outside (downstream side).

  In the sound insulating louver 1 shown in the embodiment of the present invention, the resonator 10 is provided so as to be embedded in the louver blade member 3, but it is not always necessary to do so. You may make it attach to 4,5.

  Moreover, in the sound insulation louver 1 shown in the embodiment of the present invention, the sound insulation louver 1 has only one type of the louver blade member 3, and the sound insulation louver 1 is arranged by arranging a plurality of the louver blade members 3 of the same form. However, if the surface of the main surfaces 4 and 5 of the louver blade member 3 is acoustically "soft" by the resonator 10, it is limited to such a mode. is not.

  In the sound insulation louver 1 shown in the embodiment of the present invention, a pair of opposing resonators 10 are provided in one propagation path 100. For example, two or more resonators 10 are provided in the propagation path 100. It is good also as such a structure.

  The louver blade member 3 constituting the sound insulating louver 1 shown in the embodiment of the present invention can be manufactured by integrating the resonator 10 with the entire louver blade member 3 and extruding it with aluminum or the like. On the other hand, the resonator 10 may be manufactured as described below.

  Next, the manufacturing process of the resonator 10 constituting the sound insulation louver 1 will be described. FIG. 4 is a diagram for explaining a manufacturing process example of the resonator 10 used in the sound insulation louver 1 according to the embodiment of the present invention.

  The outer shell member 20 is a rectangular parallelepiped box-shaped member in which one of the six surfaces is an opening surface 25. The L-shaped member 30 is a member having an L-shaped cross section and two surfaces that are orthogonal to each other.

  As shown in FIG. 4, the resonator 10 can be manufactured by attaching two L-shaped members 30 as described above to the opening surface 25 of the outer shell member 20.

  A space between the two L-shaped members 30 attached to the opening surface 25 of the outer shell member 20 is a slit-shaped opening 50. In addition, one of the two surfaces of the L-shaped member 30 functions as the partition wall 60 of the resonator 10.

  In the manufacturing method of the resonator 10 as described above, by preparing the outer shell member 20 and the L-shaped member 30 having various dimensions in advance, the resonator 10 corresponding to the frequency to be reduced is manufactured, and this resonance is performed. By disposing the vessel 10 on the louver blade member 3, it is possible to configure the sound insulation louver 1 capable of easily changing the frequency to be reduced.

  As described above, in the sound insulating louver 1 according to the present invention, the resonator 10 having the slit-shaped opening 50 with an acoustic impedance ratio of 0 is arranged so that the slit-shaped opening 50 faces the inner surface of the propagation path 100. Since they are arranged in pairs, according to the sound insulation louver 1 according to the present invention, the type and number of components can be reduced as the sound insulation louver 1 in the propagation path 100, the structure is simplified, the apparatus is downsized, It is possible to reduce the weight, and it is possible to reduce costs associated with an increase in manufacturing, transportation, and construction man-hours.

  Moreover, according to the sound insulation louver 1 which concerns on this invention, it can cope with the noise from various directions, and it becomes possible to ensure sufficient sound insulation performance.

  Next, another embodiment of the present invention will be described. FIG. 5 is a diagram showing an application example of the sound insulation louver 1 according to another embodiment of the present invention to the propagation path 100. FIG. 5 shows a pair of resonators 10 that are opposed to each other from the propagation path 100 of the sound insulation louver 1. In FIG. 5, the partition wall portion 60 is not shown because the drawing becomes complicated.

  In the embodiment shown in FIG. 5, a three-partition plate member 70 is provided between the opposing resonators 10, and the resonator 10 includes the first section 11, the second section 12, the third section 13, and the fourth section 14. It is divided into four sections. Here, in this embodiment, the resonator 10 is divided into four sections, but the number of sections into which the resonator 10 is divided is arbitrary. Further, the partitioning of the resonator 10 by providing such a partition plate member 70 can be applied to other than the embodiment shown in FIG.

  When the opening of the propagation path 100 is provided on the wall surface in a longitudinal direction with respect to the horizontal direction, particularly in a situation in which noise is incident on the louver surface obliquely in the horizontal direction, the inside of the propagation path 100 path is one-dimensionally. It is also possible not to propagate.

  In such a case, as shown in FIG. 5, by providing a partition plate member 70 in the opening and the resonator 10 to be incorporated, the noise propagates one-dimensionally in the propagation path 100, and the noise generated by the resonator 10. Reduction device is effective.

  In addition, it is preferable that the space | interval which provides the partition plate member 70 shall be 1/2 or less of the wavelength of the noise to reduce.

  Further, when the noise to be reduced by the sound insulation louver 1 has a plurality of peak frequencies in the frequency characteristics or a frequency component in a wide band, the interval between the partition plate members 70 and the like is In another preferred embodiment, the resonator 10 is set differently and provided with sections having different lengths in the horizontal direction.

  As described above, in the sound insulation louver according to the present invention, the resonator having the slit portion with an acoustic impedance ratio of 0 is arranged in pairs such that the slit-shaped opening faces the wall surface of the inner wall of the noise propagation path, for example. Therefore, according to such a sound insulation louver according to the present invention, the type and number of constituent members can be reduced as the sound insulation louver in the propagation path 100, and the structure can be simplified, the device can be reduced in size, and the weight can be reduced. It becomes possible, and it becomes possible to suppress manufacturing and an assembly cost.

  Next, another embodiment of the present invention will be described. The resonator 10 used in the present invention described so far exhibits a noise reduction effect at the resonance frequency f determined by the equation (5). The resonance frequency f can be adjusted to the frequency characteristics of noise by adjusting the dimensions A, B, C, a, and l shown in FIG.

  However, when the target noise to be reduced by the resonator 10 has a plurality of peak frequencies in the frequency characteristics or a frequency component in a wide band, the resonators 10 having different resonance frequencies are combined. There is a need.

  Therefore, in the resonator 10 used in the sound insulation louver 1 according to another embodiment, a casing having a plurality of resonance frequencies is configured with simple and few members. More specifically, in the sound insulation louver 1 according to the present embodiment, the resonator 10 includes a rectangular parallelepiped outer shell member 20 (one already described) and a single plate-shaped partition. It is comprised by the plate member 35 and the L-shaped member 30 (same as already demonstrated) from which a dimension differs.

  FIG. 6 is a diagram illustrating a resonator 10 used in a sound insulation louver 1 according to another embodiment of the present invention.

  FIG. 6A is an exploded perspective view of the resonator 10 used in the sound insulation louver 1 according to another embodiment. FIG. 6B is a perspective view of the resonator 10 used in the sound insulation louver 1 according to another embodiment. FIG. 6C is a cross-sectional view of the propagation path 100 of the sound insulation louver 1 as viewed from another embodiment, with the longitudinal direction of the propagation path 100 (or the longitudinal direction of the slit-like opening 50) cut perpendicularly. It is.

  As shown in FIGS. 6 (A) and 6 (B), two L-shaped members 30 as described above and one partition plate member 35 are attached to the opening surface 25 of the outer shell member 20. The resonator 10 can be manufactured. In this case, the partition plate member 35 also functions as the partition wall portion 60.

By combining the outer shell member 20, the L-shaped member 30, and the partition plate member 35 as shown in FIG. 6, two slit resonators having the space A and the space B can be configured in one resonator. . In each resonator, the acoustic impedance ratio Z of the slit portion 50 becomes substantially 0 at the resonance frequencies f ₁ and f ₂ , respectively, and these are opposed to the wall surface of the propagation path 100 as shown in FIG. The noise reduction effect is exhibited for a plurality of frequencies.

  The sound insulation louver 1 according to another embodiment as described above can be used for various resonances by using the outer shell member 20 and the partition plate member 35 having the same dimensions as long as the position of the partition plate member 35 and the dimensions of the L-shaped member 30 are changed. A resonator 10 having a frequency can be configured.

  Note that the “space” such as the space A and the space B is underlined in the drawing.

  FIG. 7 is a cross-sectional view of the resonator 10 applied to the propagation path 100 of the sound insulation louver 1 according to another embodiment of the present invention. FIG. 7 is a cross-sectional view of the propagation path 100 as viewed by cutting the longitudinal direction (or the longitudinal direction of the slit-shaped opening 50) perpendicularly.

  As shown in FIG. 7, if the number of partition plate members 35 and L-shaped members 30 is increased, three slit resonators having a space A, a space B, and a space C can be formed, and one outer shell member 20 is formed. It is possible to construct a resonator 10 having three or more different resonance frequencies. In this case, the partition plate member 35 also functions as the partition wall portion 60.

  FIG. 8 is a sectional view of the resonator 10 applied to the propagation path 100 of the sound insulation louver 1 according to another embodiment of the present invention. FIG. 8 is a cross-sectional view of the propagation path 100 when viewed in the longitudinal direction (or the longitudinal direction of the slit-like opening 50).

In sound insulation louvers 1 according to another embodiment of FIG. 8, the resonator 10 is two resonators consisting of the space A and the space C is a structure separated by two partition plates member 35 away interval a _t It has become. In this case, the slit between the two resonators becomes a slit-like opening 50 having no air layer behind. In this case, the partition plate member 35 also functions as the partition wall portion 60.

If such were the resonator 10 and opposed along the inner wall of the channel 100, with respect to the frequency interval a _t the cross-sectional dimensions and the partition plate member 35 of the channel 100 is equal to or less than a half wavelength, an air layer behind The slit-shaped opening 50 that does not have a function as an acoustic tube (space B).

In this case, the dimension D of the outer shell member 20 corresponds to the pipe length of the acoustic tube, in the frequency f _t and its odd multiples of a frequency 1/4 is equal to D of wavelength, acoustic slit opening 50 of the acoustic tube Impedance ratio Z becomes 0 and the noise reduction effect is exhibited.

In general, the above-described f _t is higher than the resonance frequency f ₁ or f ₂ of the slit resonator (space A and space C in FIG. 7), and therefore a structure in which the slit resonator and the acoustic tube are combined as shown in FIG. The sound insulation louver 1 using the resonator 10 can exhibit a noise reduction effect for a wide range of frequencies.

Incidentally, Again, spacing a _t the cross-sectional dimensions and the partition plate of the propagation path for frequencies equal to or less than the half wavelength, the slit having no air layer behind serves as an acoustic tube. The prior arts described in Japanese Patent Nos. 383,263 and 5,454,369 require a large number of partition plates in order to form an acoustic “tube” having a rectangular cross section. On the other hand, in the present invention, these partition plates are unnecessary.

  Next, another embodiment of the present invention will be described. FIG. 9 is a view showing a sound insulation louver 1 according to another embodiment of the present invention. In the embodiments described so far, the resonators 10 are disposed opposite to each other of the propagation path 100 so that the surfaces of the main surfaces 4 and 5 of the louver blade member 3 are in an acoustically “soft” state. I was doing.

  On the other hand, in this embodiment, the resonator 10 is arranged only on one side of the propagation path 100 to attempt to reproduce an acoustically “soft” state. In the sound insulation louver 1 according to the present embodiment, FIG. 9A shows a case where the resonator 10 is “one-sided” in the propagation path 100, and FIG. 9B shows that the resonator 10 is placed in the propagation path 100. Each of the cases of “one side parallel arrangement” is shown.

  According to the numerical analysis method using the two-dimensional boundary element method, it can be confirmed that the method of “facing the resonators 10” is more effective as a noise reduction method than the other methods. When it is understood that sufficient noise reduction effects can be expected for the placement methods such as “placement” and “one-sided parallel placement”, and only “one-sided placement” or “one-sided parallel placement” can be used for layout reasons. Such an arrangement can also be adopted as appropriate.

  Next, another embodiment of the present invention will be described. FIG. 10 is a diagram illustrating a resonator 10 used in a sound insulation louver 1 according to another embodiment of the present invention. FIG. 10A shows the resonator 10 used in the sound insulation louver 1 according to the embodiment described so far, and FIG. 10B shows the resonator 10 used in the sound insulation louver 1 according to this embodiment. Yes. The sound insulation louver 1 according to this embodiment is characterized in that the resonator 10 shown in FIG.

  As shown in FIG. 10A, the resonator 10 of the sound insulating louver 1 according to the embodiment described so far is arranged on both sides of the slit portion 50 and provided with partition walls 60, and these partition walls 60 have a depth. It had a length of 1 in the direction.

  On the other hand, the resonator 10 of the sound insulation louver 1 in this embodiment shown in FIG. 10B has a structure in which the partition walls 60 on both sides of the slit portion 50 are omitted. Although the partition wall portion 60 is omitted, the plate thickness of the front surface of the resonator 10 including at least the slit portion 50 has a thickness of 1 instead.

With the plate thickness l, V _n described in the first embodiment is generated also in the resonator 10 used in the present embodiment. Thus, the sound insulation louver 1 according to this embodiment using the resonator 10 from which the partition wall 60 is omitted can also enjoy the same effects as those of the sound insulation louver 1 described so far.

  As described above, in the sound insulation louver according to the present invention, the resonator having the slit-shaped opening having an acoustic impedance ratio of 0 is arranged in the propagation path 100, and according to such a sound insulation louver according to the present invention, the structure Therefore, the cost associated with an increase in manufacturing, transportation, and construction man-hours can be reduced.

  In addition, according to the sound insulation louver according to the present invention, it is possible to cope with noise from various directions and to ensure sufficient sound insulation performance.

  Hereinafter, since the effect of the sound insulation performance by the sound insulation louver 1 according to the present invention was confirmed by numerical calculation, the results are shown. In the following numerical calculation, the two-dimensional boundary element method was used.

  The calculation target of the numerical calculation is a louver wall in which louvers are arranged at a certain interval. FIG. 11 shows a part of three types of louver walls to be calculated. In FIG. 11, the louver blade members 3 constituting the louver wall are arranged at intervals of 100 mm, and the gap between the louver blade members 3, that is, the width of the propagation path 100 is about 42 mm. The calculation was performed assuming that the surface of the louver blade member 3 is completely reflective. As the sound source, a point sound source was arranged at a position 1.5 m away from the louver wall on the left side in the drawing, and the acoustic energy transmitted to the sound receiving side (right side in the drawing) of the louver wall was obtained by calculation.

  The sound source side space and the sound receiving side space are connected by an opening having a height of 1.26 m, and a louver wall is disposed in the opening. As a comparison object, acoustic energy that passes through a simple opening in which no louver wall is arranged is obtained by calculation, and the amount of acoustic energy reduced by the presence or absence of the louver wall is evaluated as insertion loss of the louver wall, that is, noise reduction performance.

  FIG. 11A shows a louver wall where the resonator 10 is not arranged. Hereinafter, this shape is referred to as a “basic shape”. On the other hand, what is shown in FIGS. 11B and 11C corresponds to the sound insulation louver 1 according to the present invention in which the resonator 10 is disposed. FIG. 11B shows a form in which the openings of the resonator 10 are arranged facing each other across the ventilation path, and FIG. 11C shows a form in which the resonator 10 is arranged only on one side of the ventilation path. It is.

  That is, FIG. 11B corresponds to the embodiment shown in FIG. 3 in which a pair of opposed resonators 10 are provided. Hereinafter, this shape is referred to as “opposing arrangement”.

  FIG. 11C corresponds to the embodiment shown in FIG. 9A in which the resonator 10 is arranged on one side in the propagation path. Hereinafter, this shape is referred to as “one-sided arrangement”.

  The dimensions of the resonator 10 to be arranged are B = 22, C = 40, a = 2.5, and l = 5 (all the units are mm). Each symbol corresponds to the symbol described in FIG. Since this is a two-dimensional analysis, the length of the resonator 10 is A = ∞. With the above dimensions, the resonance frequency of the resonator 10 is about 1 kHz.

  The numerical calculation is performed for a pure tone every 1/15 octave, and the obtained sound energy that is transmitted to the receiving side is averaged by 5 energy centered on the center frequency of 1/3 octave band, so that 1/3 octave band is obtained. The calculation result was as follows. From the obtained calculation results, the amount of acoustic energy reduced by the louver wall with the simple opening as a reference was calculated as described above, and the insertion loss of the sound insulation louver was calculated.

FIG. 12 shows the frequency characteristics of the insertion loss of each louver wall shown in FIG. Higher values indicate higher noise reduction performance.
Compared to the “basic shape”, the “oppositely arranged” sound insulating louver 1 and the “one-sided arranged” sound insulating louver 1 according to the present invention in which the resonator 10 is arranged have a noise centering on the 1 kHz band close to the resonance frequency of the resonator 10. It can be confirmed that a reduction effect is obtained.

  In the sound insulation louver 1 according to the present invention, “opposite arrangement” is basically used, but a form such as “one side arrangement” can also be adopted for convenience of layout and the like. As shown in FIG. 12, even in “one-sided arrangement”, it is shown that a certain noise reduction effect is obtained centering on the resonance frequency of the resonator 10. However, it is also shown that the “opposing arrangement” has a greater noise reduction effect near the resonance frequency of the resonator 10 than the “one-side arrangement”.

  From the above results, it can be confirmed that the sound insulation louver 1 according to the present invention using the resonator 10 is effective as a method of reducing the louver transmitted sound. It can also be confirmed that a great noise reduction effect can be obtained particularly when the resonator 10 is “opposed”.

DESCRIPTION OF SYMBOLS 1 ... Sound insulation louver 3 ... Louver blade member 4, 5 ... Main surface 10 ... Resonator 11 ... 1st division 12 ... 2nd division 13 ... 3rd division 14- .. fourth section 20 ... outer shell member 25 ... opening surface 30 ... L-shaped member 35 ... partition plate member 40 ... casing 50 ... slit-like opening 60 ... Partition part 70 ... partition plate member 100 ... propagation path

Claims (5)

The louver blade member is a sound insulation louver arranged in a plurality of consecutively,
A sound insulating louver, wherein a resonator having a slit-like opening is disposed on the louver blade member. The sound insulating louver according to claim 1, wherein a resonator is disposed on each of two main surfaces of the louver blade member. The sound insulation louver according to claim 1, wherein the slit-like openings of the resonators of the adjacent louver blade members are arranged to face each other. The sound insulation louver according to any one of claims 1 to 3, wherein the resonator is embedded in the louver blade member. The sound insulation louver according to any one of claims 1 to 4, wherein the resonator is divided into a plurality of sections by a partition plate member.

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