JPH04140306A - Interference type noise insulation device - Google Patents
Interference type noise insulation deviceInfo
- Publication number
- JPH04140306A JPH04140306A JP26051090A JP26051090A JPH04140306A JP H04140306 A JPH04140306 A JP H04140306A JP 26051090 A JP26051090 A JP 26051090A JP 26051090 A JP26051090 A JP 26051090A JP H04140306 A JPH04140306 A JP H04140306A
- Authority
- JP
- Japan
- Prior art keywords
- noise
- hollow
- pipe
- interference type
- length
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000009413 insulation Methods 0.000 title 1
- 230000003111 delayed effect Effects 0.000 claims abstract description 11
- 230000005855 radiation Effects 0.000 claims description 2
- 230000000644 propagated effect Effects 0.000 abstract description 6
- 230000001603 reducing effect Effects 0.000 abstract 1
- 230000000694 effects Effects 0.000 description 9
- 238000010586 diagram Methods 0.000 description 4
- 230000001902 propagating effect Effects 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000001066 destructive effect Effects 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Devices Affording Protection Of Roads Or Walls For Sound Insulation (AREA)
- Railway Tracks (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、干渉型防音装置に関するもので、特に、騒音
源から伝播する騒音の一部を中空貫通管路に通過させる
ことにより、遅延させ、この遅延伝播音と騒音源からの
直接伝播音とを干渉させることにより減音された干渉領
域を防音壁との組合せにより形成させる干渉型防音装置
に関するものである。Detailed Description of the Invention (Industrial Application Field) The present invention relates to an interference type soundproofing device, and in particular to a device for delaying noise propagating from a noise source by passing a part of the noise through a hollow through pipe. The present invention relates to an interference type soundproofing device that forms a sound-attenuated interference region by causing the delayed propagation sound to interfere with the directly propagated sound from the noise source in combination with a soundproofing wall.
（従来の技術）
この種の干渉型防音装置は、例えば、特公昭５４２００
６号公報、特公昭５４−４２７２８号公報に記載されて
いる干渉原理によるものである。すなわち、多数の中空
管路を具える干渉型騒音制御中空体をその騒音入射面を
騒音源に対面させて配置することにより騒音源から伝播
する騒音の一部を中空管路に通過させ、これにより位相
をづらし、騒音放射面における出口から出る遅延伝播音
と騒音源からの直接伝播音との位相差のずれを利用して
減音領域を形成する干渉原理によるもので、中空管路の
管路長、管路断面積および中空管数により目的とする騒
音の周波数領域を効率的に制御することが可能な装置で
ある。(Prior art) This type of interference type soundproofing device is known, for example, from Japanese Patent Publication No. 54200.
This is based on the interference principle described in Japanese Patent Publication No. 6 and Japanese Patent Publication No. 54-42728. That is, by arranging an interference type noise control hollow body having a large number of hollow pipes with its noise incident surface facing the noise source, a part of the noise propagating from the noise source is passed through the hollow pipes. This is based on the interference principle that shifts the phase and forms a sound reduction area by utilizing the phase difference between the delayed propagation sound emitted from the exit on the noise emission surface and the direct propagation sound from the noise source. This device is capable of efficiently controlling the target noise frequency range by adjusting the length of the pipe, the cross-sectional area of the pipe, and the number of hollow pipes.
かかる干渉型防音装置は従来の防音壁と異なり上述した
伝播音の干渉現象を利用することによって、減音、防音
効果が大きく、防音壁と比べて音の回折現象が少ないた
め遠方に対しても大きな減音効果を得ることができる。Unlike conventional soundproof walls, this interference type soundproofing device utilizes the above-mentioned interference phenomenon of propagated sound, so it has a large sound reduction and soundproofing effect, and has less sound diffraction phenomenon compared to soundproofing walls, so it can be used even over long distances. A great sound reduction effect can be obtained.
また、完全に密閉できない騒音源にも有効で、熱や空気
を通すことができる等の利点を有する他に、耐水、耐候
性に優れた金属材料、無機材料の他、プラスチック材料
を素材として用いることができる利点を有する。In addition, it is effective against noise sources that cannot be completely sealed, and has the advantage of allowing heat and air to pass through. In addition, it uses metal materials, inorganic materials, and plastic materials with excellent water and weather resistance. It has the advantage of being able to
これがため、新幹線などの鉄道車両の走行に伴い発生す
る列車騒音対策あるいは、高速度道路の自動車走行騒音
対策等に上述した干渉型防音装置を用いる場合、既設の
防音壁上に干渉型騒音制御中空体を設置することにより
、狭い設置空間で低い防音壁によっても防音壁から遠く
離れた受音点で十分な減音効果が得ることができる。For this reason, when using the above-mentioned interference type soundproofing device to counter train noise caused by the running of railway vehicles such as Shinkansen trains, or to countermeasures against noise caused by automobiles running on high-speed roads, it is necessary to install an interference type noise control hollow on the existing soundproofing wall. Even with a low soundproof wall in a narrow installation space, a sufficient sound reduction effect can be obtained at a sound receiving point far away from the soundproof wall.
干渉原理にもとづく、例えば、特公昭５９−１９５９１
２号公報に記載されている騒音制御装置は、第７図に示
すように騒音制御中空体１を音１ｓから離れた位置に設
置された防音壁２上に取付けている。Based on the interference principle, for example, Japanese Patent Publication No. 59-19591
The noise control device described in Publication No. 2 has a noise control hollow body 1 mounted on a soundproof wall 2 installed at a position away from the sound 1s, as shown in FIG.
しかし、図示の構成では、騒音制御中空体１の騒音放射
面１ｂから出る遅延伝播音が直接伝播音によって十分に
干渉されず、減音効果が十分に生しない。これがため、
第８図に示すように騒音制御中空体１の後面から適当な
間隔で離間した位置に遮音壁４を設置して、未干渉の遅
延伝播音の伝播を防止していた。しかし、新幹線などの
列車の速度向上に伴う騒音増加に対応するため、防音性
能の向上が要求されている。このため、上述した公報に
開示の構造では、防音性能を増大させる結果として騒音
制御中空体が大型化し、コストが増大し、また、新幹線
などに適用する場合には、防音壁の上端部に設置される
ため、大型化による空中専用権などの問題が発生してい
る。However, in the illustrated configuration, the delayed propagation sound emitted from the noise emission surface 1b of the noise control hollow body 1 is not sufficiently interfered with by the direct propagation sound, and a sufficient sound reduction effect is not produced. Because of this,
As shown in FIG. 8, a sound insulating wall 4 is installed at a position spaced apart from the rear surface of the noise control hollow body 1 at an appropriate distance to prevent uninterfered delayed propagation sound from propagating. However, in order to cope with the increase in noise caused by the speed increase of Shinkansen and other trains, improvements in soundproofing performance are required. For this reason, in the structure disclosed in the above-mentioned publication, as a result of increasing the soundproofing performance, the noise control hollow body becomes larger and the cost increases, and when applied to Shinkansen etc., it is necessary to install it at the upper end of the soundproofing wall. As a result, problems such as air exclusive rights have arisen due to the increased size.
（発明が解決しようとする課題）
本発明は、特に、新幹線などの列車による騒音対策に好
適な小型で防音性能に優れた干渉型防音装置を捷供しよ
うとするものである。(Problems to be Solved by the Invention) The present invention is intended to provide an interference type soundproofing device that is compact and has excellent soundproofing performance, particularly suitable for countermeasures against noise caused by trains such as the Shinkansen.
（課題を解決するだめの手段）
これがため、本発明によれば、第１図に示すように、騒
音源から離れた位置に設置された防音壁２上に中空貫通
管路５を設けた干渉型防音装置において、中空貫通管路
５の少なくとも騒音入射側部分５ａを防音壁２の騒音源
側壁面に対して１０°以上の傾斜角度αで傾斜させて音
源側に延長して設けたことを特徴とする。(Means for Solving the Problem) Therefore, according to the present invention, as shown in FIG. type soundproofing device, at least the noise incident side portion 5a of the hollow through pipe 5 is inclined at an inclination angle α of 10° or more with respect to the noise source side wall surface of the soundproof wall 2, and is extended toward the sound source side. Features.
また、第３図に模式図で示すように、騒音１ｆＩｓから
中空貫通管路５の入射人口６および放射出ロアまでの距
離り、およびＬｏに対して中空貫通管路５の管路長Ｌ２
を適切に選定して中空貫通管路５を通過した遅延伝播音
が中空貫通管路５を通過しない直接伝播音と％波長の位
相差を有するよう構成するのがよい。In addition, as shown schematically in FIG. 3, the pipe length L2 of the hollow penetrating pipe 5 is calculated from the distance from the noise 1fIs to the incident population 6 and the radiation lower of the hollow penetrating pipe 5, and Lo.
It is preferable to appropriately select the delay propagation sound that has passed through the hollow through pipe 5 to have a phase difference of % wavelength from the directly propagated sound that has not passed through the hollow through pipe 5.
また、本発明によれば、中空貫通管路５を平行な複数列
で設け、騒音源Ｓから遠い側に位置する中空貫通管路５
−１の長さより近い側に位置する中空貫通管路５−２．
５−３．−−一の長さを順次短くするとともに騒音源Ｓ
から遠い側の中空貫通管路５−１の断面積より近い側の
中空貫通管路５−２．５−３．−ｍ−の断面積を順次小
さくするのがよい。Further, according to the present invention, the hollow through pipes 5 are provided in a plurality of parallel rows, and the hollow through pipes 5 located on the side far from the noise source S
Hollow through pipe 5-2 located on the side closer to the length of -1.
5-3. --Sequentially shorten the length of the noise source S
The cross-sectional area of the hollow through pipe 5-1 on the side farther from the hollow through pipe 5-2.5-3. It is preferable to sequentially reduce the cross-sectional area of -m-.
（作 用）
本発明によれば、例えば、新幹線などの場合、軌道と車
輪との間の騒音源Ｓから車体と防音壁との間を経て外部
に拡がる騒音の一部が中空管路５を通過することによっ
て騒音源Ｓからの直接伝播騒音に対して位相がずれ、こ
れにより、中空管路５を通過した遅延伝播音と直接伝播
音とが車体と防音壁との間で干渉することによって騒音
レベルを低減することができ、特に、中空貫通管路を騒
音源側防音壁面に対して１０°以上の傾斜角度で傾斜さ
せることによって、中空貫通管路が防音壁から車体に向
は延長し、防音壁と車体との間で直接伝播音と遅延伝播
音とを干渉させて騒音を著しく減音することができる。(Function) According to the present invention, for example, in the case of a Shinkansen, a part of the noise that spreads from the noise source S between the track and the wheels to the outside through the space between the car body and the soundproof wall is transferred to the hollow pipe 5. The delayed propagation sound that passed through the hollow pipe 5 and the direct propagation sound interfere with each other between the vehicle body and the soundproof wall. In particular, by inclining the hollow through pipe at an inclination angle of 10° or more with respect to the soundproof wall surface on the noise source side, the hollow through pipe can be directed from the soundproof wall toward the vehicle body. By extending the soundproof wall and interfering with delayed propagation sound between the soundproof wall and the vehicle body, noise can be significantly reduced.
さらに干渉型防音装置を狭い空間に設置することができ
るとともに、構造が簡単になるため、防音性能向上によ
る形状増はなく、防音壁の外側に設置する場合には、Ｂ
Ｔ足場など工事設備が必要とされるが、防音壁の内側に
設置することにより、工事設備費の大幅な節減が期待で
きる。In addition, the interference type soundproofing device can be installed in a narrow space, and the structure is simple, so there is no need to increase the size due to improved soundproofing performance, and when installing it outside the soundproofing wall, B
Construction equipment such as T-scaffolding is required, but by installing it inside the soundproof wall, significant savings in construction equipment costs can be expected.
また、本発明によれば、騒音制御中空体の中空貫通管路
５の長さり、を適切に選定して中空貫通管路５を通過し
た騒音が直接伝播音に対してη波長遅れるようにするこ
とにより、車体８と騒音制御中空体１との間の空間内で
最大の破壊的干渉作用を生ぜしめ、騒音を著しく減音す
ることができる。Further, according to the present invention, the length of the hollow through pipe 5 of the noise control hollow body is appropriately selected so that the noise passing through the hollow through pipe 5 lags behind the directly propagated sound by η wavelengths. This produces the maximum destructive interference effect in the space between the vehicle body 8 and the noise-controlling hollow body 1, making it possible to significantly reduce noise.
（実施例） 本発明の一実施例を第３図および第４図に示す。(Example) An embodiment of the invention is shown in FIGS. 3 and 4.
図示の干渉型騒音制御中空体ｌは合成樹脂その地回様の
材料で造られ管路長の異なる複数個の貫通中空管路５が
互に平行な複数列で設けられている。The illustrated interference type noise control hollow body 1 is made of a material similar to synthetic resin and has a plurality of through-hole hollow pipes 5 having different pipe lengths arranged in a plurality of parallel rows.
この騒音制御中空体１は騒音源Ｓから離れた位置に設置
された防音壁２の上端部２ａの音源側に中空管路５の騒
音入射面側部分５ａが防音壁２の騒音側壁面２ａに対し
１０゛以上の傾斜角度αで傾斜して延長するよう取付け
られ、騒音源Ｓから騒音放射面１ｂにおける出ロアまで
の距離をＬｏとし、騒音放射面１ａにおける入口６まで
の距離をＬｌ、入口６から出ロアまでの管路長をＬ２と
し、これにより中空管路５を通過した遅延伝播音が直接
伝播音と２波長の遅れを生じるように構成されている。This noise control hollow body 1 has a noise incident surface side portion 5a of the hollow pipe 5 on the sound source side of the upper end 2a of the soundproof wall 2 installed at a position away from the noise source S. , the distance from the noise source S to the lower output on the noise emission surface 1b is Lo, the distance to the inlet 6 on the noise emission surface 1a is Ll, The length of the pipe from the inlet 6 to the outlet lower is set to L2, so that the delayed propagation sound passing through the hollow pipe 5 is delayed by two wavelengths from the direct propagation sound.
さらに、騒音源Ｓから遠い側に位置する中空貫通管路５
−１の長さより近い側に位置する中空貫通管路５−２．
５−３．−一−の長さを順次短かくするとともに騒音源
Ｓから遠い側の列の中空貫通管路５−１の断面積より近
い側の中空貫通管路５−２．５−３．−−−の断面積を
順次小さくし、これにより、全ての中空貫通管路５−Ｌ
５−２．５−３．−−−−において同様の遅れが生じ
るようにするとともに、減音目的とする騒音の周波数領
域を効率的に制御することが可能である。Furthermore, the hollow through pipe 5 located on the far side from the noise source S
Hollow through pipe 5-2 located on the side closer to the length of -1.
5-3. -1- The lengths of the hollow through pipes 5-2, 5-3 are sequentially shortened, and the cross-sectional area of the hollow through pipes 5-1 in the row far from the noise source S is closer to that of the hollow through pipes 5-1. --- The cross-sectional area of 5-L is gradually reduced.
5-2.5-3. It is possible to cause a similar delay to occur in ---- and to efficiently control the frequency range of the noise that is targeted for sound reduction.
第５図は本発明による干渉型防音装置を設置した場合（
１）と防音壁だけの場合（Ｉ［）との減音効果を比較し
た実施テスト結果を示し、その測定方法を第６図に示す
。第６図に示すように、新幹線車体モデル９を設置して
、騒音源Ｓを新幹線車体モデルのレール／車輪位置に置
き、干渉型騒音制御中空体ｌを騒音′ａＳから水平路Ｉ
ｆ ａ ＋で２．５ｍ離れた防音壁２の上端部の音源側
に取付け、騒音源Ｓから中空体１の取付位置上端までの
高さ（ｈ、）を２ｍとし、防音壁２より水平距離ｄ２で
２５ｍ離れた点で、地上より２ｍの高さ（ｈ２）の受音
点Ｐで測定した。Figure 5 shows the case where the interference type soundproofing device according to the present invention is installed (
The results of a test comparing the sound reduction effect between 1) and the case of only soundproof walls (I[) are shown, and the measurement method is shown in FIG. As shown in FIG. 6, the Shinkansen car body model 9 is installed, the noise source S is placed at the rail/wheel position of the Shinkansen car body model, and the interference type noise control hollow body l is moved from the noise 'aS to the horizontal road I.
It is installed on the sound source side of the upper end of the soundproof wall 2, which is 2.5 m away at f a +, and the height (h,) from the noise source S to the upper end of the mounting position of the hollow body 1 is 2 m, and the horizontal distance from the soundproof wall 2 is Measurement was made at a sound receiving point P at a height of 2 m above the ground (h2) at a point 25 m away at d2.
（発明の効果）
第５図のグラフで示すように、防音壁のみと比較して本
発明によれば減音効果を太き（向上させることができる
。さらに、本発明によれば、乗客に対しても車内騒音を
確実に低減することができる。(Effects of the Invention) As shown in the graph of FIG. In-vehicle noise can also be reliably reduced.
第１図は本発明による装置の概略線図、第２図は本発明
の原理図、
第３図は本発明による干渉型防音装置の１実施例を示す
線図的縦断面図、
第４図は第３図に示す装置の線図的正面図、第５図は本
発明による干渉型防音装置の減音効果を示す特性曲線図
、
第６図は第５図に示す減音効果の測定方法を示す線図的
縦断面図、
第７および第８図は従来装置の概略線図である。
１・・・干渉型騒音制御中空体
２・・・防音壁
５・・・中空管路
第１図
第５図
第６図
第７図FIG. 1 is a schematic diagram of a device according to the present invention, FIG. 2 is a principle diagram of the present invention, FIG. 3 is a diagrammatic longitudinal sectional view showing one embodiment of an interference type soundproofing device according to the present invention, and FIG. is a diagrammatic front view of the device shown in FIG. 3, FIG. 5 is a characteristic curve diagram showing the sound reduction effect of the interference type soundproofing device according to the present invention, and FIG. 6 is a method for measuring the sound reduction effect shown in FIG. FIGS. 7 and 8 are schematic diagrams of a conventional device. 1... Interferential noise control hollow body 2... Soundproof wall 5... Hollow pipe line Figure 1 Figure 5 Figure 6 Figure 7
Claims (1)
貫通管路を設けた干渉型防音装置において、前記中空貫
通管路の少なくとも騒音入射側部分を防音壁の騒音源側
壁面に対して１０°以上の傾斜角度で傾斜させて音源側
に延長して設けたことを特徴とする干渉型防音装置。 ２、騒音源から中空貫通管路の入射入口および放射出口
までの距離に対して中空貫通管路の管路長さを適切に選
定して中空貫通管路を通過した遅延伝播音が直接伝播音
と１／２波長の位相差を有するよう構成した請求項１記
載の干渉型防音装置。 ３、前記中空貫通管路を平行な複数列で設け、騒音源に
遠い側の中空貫通管路の長さより近い側の中空貫通管路
の長さを順次短かくし、かつ、騒音源に遠い側の中空貫
通管路の断面積より近い側の中空貫通管路の断面積を順
次小さくしたことを特徴とする請求項１記載の干渉型防
音装置。[Claims] 1. In an interference type soundproofing device in which a hollow through pipe is provided on a soundproof wall installed at a position away from a noise source, at least the noise incident side portion of the hollow through pipe is connected to the soundproof wall. An interference type soundproofing device, characterized in that the device is inclined at an inclination angle of 10° or more with respect to a side wall surface of a noise source and is extended toward a sound source side. 2. By appropriately selecting the length of the hollow through pipe in relation to the distance from the noise source to the entrance inlet and the radiation outlet of the hollow through pipe, delayed propagation sound that passes through the hollow through pipe becomes direct propagation sound. 2. The interference type soundproofing device according to claim 1, wherein the interference type soundproofing device is configured to have a phase difference of 1/2 wavelength. 3. The hollow through pipes are provided in a plurality of parallel rows, and the length of the hollow through pipes on the side closer to the noise source is sequentially shorter than the length of the hollow through pipes on the side far from the noise source. 2. The interference type soundproofing device according to claim 1, wherein the cross-sectional area of the hollow through-pipes on the side closer to the cross-sectional area of the hollow through-pipes is successively smaller.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26051090A JPH04140306A (en) | 1990-10-01 | 1990-10-01 | Interference type noise insulation device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26051090A JPH04140306A (en) | 1990-10-01 | 1990-10-01 | Interference type noise insulation device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04140306A true JPH04140306A (en) | 1992-05-14 |
Family
ID=17348967
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26051090A Pending JPH04140306A (en) | 1990-10-01 | 1990-10-01 | Interference type noise insulation device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04140306A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0742545A2 (en) * | 1995-05-09 | 1996-11-13 | Bridgestone Corporation | Interference noise-control unit |
| WO2006115403A1 (en) * | 2005-04-26 | 2006-11-02 | Technische Universiteit Delft | Baffle board |
-
1990
- 1990-10-01 JP JP26051090A patent/JPH04140306A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0742545A2 (en) * | 1995-05-09 | 1996-11-13 | Bridgestone Corporation | Interference noise-control unit |
| EP0742545A3 (en) * | 1995-05-09 | 1997-07-16 | Bridgestone Corp | Interference noise-control unit |
| WO2006115403A1 (en) * | 2005-04-26 | 2006-11-02 | Technische Universiteit Delft | Baffle board |
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