JP3583644B2

JP3583644B2 - Soundproofing material

Info

Publication number: JP3583644B2
Application number: JP07526999A
Authority: JP
Inventors: 博文柿本; 治木曽
Original assignee: Hayakawa Rubber Co Ltd
Current assignee: Hayakawa Rubber Co Ltd
Priority date: 1999-03-19
Filing date: 1999-03-19
Publication date: 2004-11-04
Anticipated expiration: 2019-03-19
Also published as: JP2000265593A

Description

【０００１】
【発明の属する技術分野】
本発明は、発音体の外部に取り付けられ、この発音体の騒音を低減する防音材に関する。
【０００２】
【従来の技術】
従来より、防音に関しては、遮音材、吸音材、防振材、制振材を使用して、様々な対策が採られている。近年、特に人の居住空間については、防音対策が全く行われていないものは無いという状況にまできている。
【０００３】
ところが一方で、音は、皆無の状況にすること自体非常に困難であるから、ある音源が改良されると、その音源でマスキングされ、気にならなかった音源が気になり始めるという、音源の性質や状況がある。そのため、技術的及び許容コストの点で、より一層軽く、安く、省スペースで防音することが求められ、特に技術面においては、低周波数域に有効な防音材が求められている。
【０００４】
【発明が解決しようとする課題】
従来から多くの場面で使用されている面密度の高い遮音材は、低周波数で防音性能の落ち込みがある。この落ち込みは、遮音材の厚みを相当量増さなければ防ぐことができず、実用上、重量増、コストの面等で不可能である。一方、かかる遮音材は、高周波側において、一般的にコインシデンス効果による性能低下があり、単体では充分とは言い難い。
【０００５】
かかる低周波側と高周波側の性能低下を防ぐには、吸音材が用いられる。しかし、吸音材も１ｍ以上の厚みのものが使えれば別であるが、人の通常の居住空間を考えると、そのような嵩高で使用できるスペースは皆無に近い。したがって、遮音材や吸音材で、低周波数や高周波数の騒音を対策するのは困難を極める。
【０００６】
現状では、低周波音が生じる振動源や音源自体を対策する方法が考えられる。しかし、現実には、例えば、床の重量衝撃音のように、一担発生した低周波音を有効に防止する方法は知られていない。
【０００７】
また、防音対策上、耳障りな高周波音は、何らかの対策によって改善する必要があるが、かかる高周波音を、低コストで狙いの音量に調整する容易かつ低コストな方法も知られておらず、かかる高周波音の対策には、多くの期待が寄せられている。
【０００８】
本発明は、低周波数の騒音に有効な防音材を得ることを目的とする。また、本発明は、改善し得る周波数をコントロールすることができ、広範な周波数の騒音に有効な防音材を得ることを目的とする。
【０００９】
【課題を解決するための手段】
本発明は、発音体の外部に取り付けられ、前記発音体の騒音を低減する防音材であって、前記防音材が、複数の振動体と前記各振動体を支える板状遮音体とを備えており、前記板状遮音体が、各種ゴム、ポリマー、ゴムアスファルトを単独又は併用したシートやフィルム、不織布、フェルトを単独若しくは併用したものであり、前記各振動体が前記板状遮音体の少なくとも片面上に固定されており、前記各振動体が互いに所定の間隔で離間しており、前記板状遮音体の周辺部が曲げられ、枠材によって引っ張られており、前記枠材が前記板状遮音体の張力を保持しており、前記発音体の放射音によって前記各振動体が振動することを特徴とする、防音材に係るものである。
【００１０】
本発明者は、低周波数の騒音に有効で、軽く、省スペース、低コストな防音材を得るため、種々の防音材を試作し詳細に検討した。
【００１１】
その結果、本発明者は、所定の板状遮音体の少なくとも片面上に複数の振動体を固定し、それぞれの振動体を互いに所定の間隔で離間させた防音材によって、低周波数の騒音が効率的に改善できることを突き止め、本発明に至った。
【００１２】
また、本発明者は、かかる防音材が、種々の手段によって、低周波数の騒音を低減させながら、中・高周波数の騒音をコントロールでき、広範な周波数の騒音を低減させることができるという、注目すべき事実を確認し、本発明を完成させた。
【００１３】
本発明者は、本発明の防音材が低周波数の騒音を低減する機構について、充分に解明した訳ではない。本発明者が行った種々の試験、それらの結果より類推すると、本発明では、板状遮音体に固定された複数の振動体が、低周波数の音によって自ら振動し、この振動が板状遮音体の張力によって減衰されることで、低周波数の騒音が吸収されると考えられる。
【００１４】
高周波数の音は、波長が短く、エネルギーも小さいため、比較的遮音し易いが、本発明では、板状遮音体の面密度が低くても高周波音の低減ができ、防音材のより一層の軽量化が可能である。一方、低周波数の音は、波長が長く、エネルギーも大きいため、質量則に従って遮音するとすれば、重量増となり、完全に遮音するのは困難である。
【００１５】
本発明では、複数の振動体が、音波により振動に曝され、音のエネルギー損失を効率的に引き起こす。このようにして、本発明の防音材は、騒音を低減させ、特に低周波領域では有効に働くこととなる。
【００１６】
本発明によれば、シート、フィルム、布、網状物等の板状遮音体に対し、点状に無数の振動体を設けた構造を採用することによって、防音対象としての発音体の低周波の騒音を著しく改善することができる。
【００１７】
また、本発明の防音材によれば、振動体や板状遮音体の材質や配置を調節することによって、防音し得る周波数を低周波数から高周波数までの広範囲にわたって調整することができる。
【００１８】
【発明の実施の形態】
図面を参照して、本発明を詳細に説明する。
図１（ａ）は、本発明の一参考例の防音材の部分縦断面図である。図１（ｂ）は、図１（ａ）の防音材の平面図である。図２（ａ）は、本発明の他の参考例の防音材の部分縦断面図である。図２（ｂ）は、図２（ａ）の防音材の平面図である。図３（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。図３（ｂ）は、図３（ａ）の防音材の部分拡大縦断面図である。図４（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。図４（ｂ）は、図４（ａ）の防音材の平面図である。図５（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。図５（ｂ）は、図５（ａ）の防音材の平面図である。
【００１９】
図６は、本発明の一例の防音材の縦断面図である。図７（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。図７（ｂ）は、図７（ａ）の防音材の平面図である。図８（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。図８（ｂ）は、図８（ａ）の防音材の平面図である。図９は、本発明の更に他の参考例の防音材の縦断面図である。図１０は、本発明の更に他の参考例の防音材の部分縦断面図である。図１１は、本発明の更に他の参考例の防音材の縦断面図である。
【００２０】
図１〜図１１には、発音体の外部に取り付けられ、この発音体の騒音を低減する、本発明の参考例及び実施例の防音材を示す。図１に示す防音材１は、複数の振動体２と各振動体２を支える板状遮音体３とを備えており、各振動体２が板状遮音体３の少なくとも片面上に固定されており、各振動体２が互いに所定の間隔で離間しており、各振動体２が発音体の放射音によって振動する。
【００２１】
本発明にかかる板状遮音体は、振動体を支持固定するものである。かかる板状遮音体は、振動体を固定支持することができ、振動体により全体として又は部分的に振動するものであればよい。かかる板状遮音体は、全体としてどのような防音性能を得たいのかや、コストの許容範囲、重量やスペースの許容範囲により、必ずしも面密度の高いものでなくとも、本発明にかかる低周波数騒音の低減効果を発揮させることができる。
【００２２】
かかる板状遮音体には、各種ゴム、ポリマー、ゴムアスファルトを単独又は併用したシートやフィルム、網状物、織布、不織布、フェルトを単独若しくは併用したものを用い、これらの材質に特に制約はない。
【００２３】
本発明にかかる振動体は、特に材質等の制約はないが、目標性能や設置スペース及びコスト等により下記の具体例を参考に決定すればよい。その具体例は、タイル、セメント、石膏、ガラス等の無機質物、また、鉛、鉄、銅、ステンレス等の金属類や合金類、さらに、ゴム、ポリマ等の有機質物等を単独又は併用することで得られるものを用いることができる。
【００２４】
本発明の参考例では、図２（ａ）及び図２（ｂ）に示すような防音材４が含まれる。この防音材４では、振動体５と板状遮音体６とを、同一又は同質の材料から形成される。かかる場合、振動体５は、図２（ａ）に示すように、振動を受け易く、揺れ易いように、板状遮音体から突出した凸部として形成される。
【００２５】
また、本発明の防音材は、振動体や板状遮音体を、比重の異なる２種以上の成分から成形することができる。例えば、ゴムやポリマの粉砕品と、金属粉、金属酸化物粉末、砂等の高比重物との混合物から成形することができる。さらに、かかる防音材は、板状遮音体を成型すると同時に、その表面の凸部として、図２（ａ）及び（ｂ）に示すような振動体を形成してもよい。
【００２６】
かかる場合、振動体及び板状遮音体の少なくとも一方が、比重の異なる２種以上の成分からなり、防音材を板状遮音体の平面に垂直な断面で見たとき、振動体の表面側に高比重の成分が偏るように形成することができる。
【００２７】
かかる防音材の一例を、図３（ａ）及び（ｂ）に示す。この防音材７は、図３（ｂ）に示すように、振動体８の表面側に重質成分９が偏在することによって、防音材７に比重勾配を生じさせる。かかる防音材７は、振動体８が振動し易くなり、低周波側の騒音がより一層低減され易い。
【００２８】
かかる振動体は、高比重粉粒体と液状ポリマーとを使って、回転成型や比重差沈降成型によって、断面的に比重勾配を有するようにさせて成形することができる。
【００２９】
かかる比重勾配を有する振動体は、図３（ａ）に示す振動体のみならず、板状遮音材にも、外周ほど重くなるように、比重勾配を設けることができる。
【００３０】
一例として示す、図３（ａ）及び（ｂ）に示すような防音材７では、板状遮音体１０も、振動体８と同様に、重質成分９が含まれており、この重質成分９は、板状遮音体１０の表面側に局在している。
【００３１】
かかる防音材は、低・中・高、何れの周波数域においても、性能の大きな低下が起きず、優れた防音性能を発揮する。これは、振動体の重心にかたよりが生じるため、より大きな振幅になり、振動体は板状遮音体に固定されており、振動によるエネルギーロスが大きくなるためと考えられる。
【００３２】
また、本発明では、かかる振動体が、図４（ａ）及び（ｂ）に示すような２層以上の異種の層からなる防音材を得ることができる。この防音材１１では、振動体１２が上層１２ａと下層１２ｂとからなり、下層１２ｂが板状遮音体１３に固定されている。
【００３３】
下層として、例えば、発泡体や不織布のような変形し易い物や、粘弾性体等のような粘着性の物を介して、２層以上の形態で振動体を成形すれば、振動体の振動挙動を調節することができる。
【００３４】
かかる振動体は、振動体自体や板状遮音体の振動する周波数を調節でき、改善すべき騒音の周波数帯域を微調整することができる。
【００３５】
本発明では、各振動体は、所定の低周波数の騒音が低減されるよう、種々の間隔で設けることができる。各振動体の重心間の距離を調節することによって、改善し得る周波数域をずらすことができる。各振動体の取付間隔を複数組合せることにより、改善し得る周波数帯域を幅広く設定することができる。
【００３６】
例えば、各振動体同士が重ならないで、各振動体の重心間の距離が５〜３００ｍｍであるのが好ましい。特に、１０〜１５０ｍｍがより好ましい。振動体の重心間の距離が５ｍｍ未満では、各振動体が振動することで得られる低周波側騒音の改善効果が少なくなる。なお、かかる場合には、振動体と板状遮音体との間に大きな比重勾配を設ける等、特別な措置を加えることで、かかる問題を解消することができる。逆に、各振動体の重心間の間隔が３００ｍｍを超えると、高周波側の騒音対策が困難となり、対策可能な周波数が２ｋＨｚ以上に限られてくるので好ましくない。
【００３７】
振動体の形状は、円柱状、球状、半球状、立方体、直方体、その他任意の形状で良い。振動体の質量は、１〜２００ｇ／個が良い。特に好ましい範囲は、１〜３０ｇである。質量が１ｇ／個未満では、特に低周波域の騒音が低減され難くなる傾向がある。逆に、質量が２００ｇ／個を超えると、低周波域の騒音改善には良いが、防音材の重量が増し過ぎ、使用できる場面が限られるため、実用的でない。
【００３８】
本発明では、かかる振動体と板状遮音体とを、一体で形成しない場合、これらを種々の手段や方法を用いて固定し防音材とすることができる。例えば、粘着剤や接着剤で張り付けたり、タッカーやホッチキスで物理的に固定する方法でもよい。振動体には、種々の材質からなる種々の形状、質量のものを複数混合して用いてもよく、各振動体を種々の間隔で取り付けてもよい。
【００３９】
本発明では、かかる振動体を、板状遮音体との間で、粘弾性体や発泡体を介して接着したり固定することによって、振動体を更に振動させ易くすることができる。
【００４０】
かかる振動体は、防音材の片面だけでなく両面へ設けられていてもよい。この場合、板状遮音体の片面上に配置された一方の各振動体の間には、離間部が形成されており、板状遮音体の他の面の上に配置される他方の各振動体が、離間部の上側に位置しているように配置されるのが好ましい。
【００４１】
この例の防音材を、図５（ａ）及び（ｂ）に示す。この防音材１４は、図５（ａ）に示すように、上側振動体１５と下側振動体１６とが、それぞれ交互に上側板状遮音体１７と下側板状遮音体１８上に設けられている。また、図５（ｂ）に示すように、上側振動体１５は、所定の間隔で設けられており、それぞれの間に離間部１９が形成されている。下側振動体１６は、この離間部１９の下側に位置している。
【００４２】
このように、両側の振動体の位置が同じ位置ではなく、両側で少しずらした方が、５０〜６３Ｈｚでの改善量が良く、高周波の改善量もよい。このような構成とすることにより、振動体の揺れの位相がずれ、エネルギーロスを生じさせ易くなるので、防音効果が高くなるものと考えられる。
【００４３】
本発明では、板状遮音体に枠材を設け、この枠材に板状遮音体の張力を保持させる。かかる防音材は、板状遮音材の張力を有効に働かせることによって、改善し得る騒音の周波数をコントロールすることができる。
【００４４】
かかる防音材の例を、図６に示す。この防音材２０は、振動体２１と板状遮音体２２とを備え、各振動体２１は、図１（ｂ）に示すのと同様に、板状遮音体２２に配置されている。板状遮音体２２は、周辺部２２ａが曲げられ、枠材２３によって周辺方向に引っ張られている。板状遮音体２２の周辺部２２ａは、枠材２３と合板等の固定材２４とで挟み、釘２５を用いて留められている。
【００４５】
本発明にかかる枠材としては、板状遮音体へ張力を与え続けられるものであれば、材質や、形状等に特に制約はない。例えば、木質系材質の枠や、鉄、ステンレス、アルミ等の金属枠等を例示することができる。
【００４６】
かかる枠材は、板状遮音体の外周に設け、必要に応じて、枠に囲まれた部分を田の字状に補強材を入れ、板状遮音体の張力がかかる面積を分割してもよい。枠材によって板状遮音体に張力をかけることにより、防音材の低周波域の騒音の改善量を一段と高くすることができる。
【００４７】
かかる板状遮音体は、特に、６３〜１２５Ｈｚの低周波域の改善量を調整することができ、改善量を増加させることができる。
【００４８】
さらに、本発明では、無数の振動体が固定された板状遮音体の少なくとも一方の面に吸音材を取り付けることにより、防音対象としての発音体の高周波音を大幅に改善することができる。
【００４９】
かかる防音材の例を、図７〜図９に示す。図７（ａ）及び（ｂ）に示す防音材２６には、振動体２７とは反対側の板状遮音体２８上に吸音材２９が一面に設けられている。
【００５０】
また、かかる吸音材は、図８に示す防音材３０のように、比較的薄い吸音材３１を設けることによっても、防音性能を著しく高めることができる。
【００５１】
さらに、かかる防音材は、図９に示す防音材３２のように、振動体３３の上面と板状遮音体３４の下面とに、吸音材３５と吸音材３６とを配置することができる。
【００５２】
このように、板状遮音体を吸音材でサンドイッチしたり、片面に吸音材を積層すれば、改善し得る騒音の周波数域をずらし、改善し得る周波数帯域幅をより広くとれるようコントロールでき、かつ騒音の改善量も増すことができる。
【００５３】
かかる振動体は、吸音材と積層することによっても、振動が妨げられることなく、板状遮音体の面密度が大きくなくても、振動体の振動と吸音材の吸音効果とが発揮されることによって、高周波域での騒音の改善量を大幅に高めることができる。
【００５４】
このようにして、吸音材を設けられた防音材は、低周波域、高周波域での透過損失を一段と改善させることができる。設けられる吸音材層としては、２ｍｍ程度の薄いものでも有効であり、２０ｍｍ程度にすると中周波数域の５００Ｈｚ帯域にも有効となり、低周波側の有効領域もより広い周波数に移行する。この現象は板状遮音材の面密度や各振動体の間隔、振動体の重量によっても少しづつ変化するので、予め試験等によって微調整するのが好ましい。
【００５５】
本発明に好適に用いられる吸音材は、具体的には、グラスウール、ロックウール、フェルト、不織布等の繊維系の吸音材や、ウレタン、各種のゴム、ポリエチレン、ポリプロピレン等のポリマの粉砕品や繊維屑、ゴムやポリマーの発泡体の粉砕品等を各種バインダーで固化成型した多孔質材科系の吸音材、アルミニウム等の金属発泡成型品系の吸音材等を使用することができる。
【００５６】
また、本発明では、板状遮音体及び各振動体の一方又は双方の表面に、フィルム成形体を設けることができる。このフィルム成形体は、複数の互いに離間した凸部を備えており、各凸部が内部に空気室を有する。このフィルム成形体は、平坦フィルムと凹凸加工された凹凸フィルムとの貼り合わせによって形成されている。
【００５７】
この例の防音材を図１０及び図１１に示す。防音材３７では、振動体３８とは反対側の板状遮音体３９の表面にフィルム成形体４０が設けられている。フィルム成形体４０は、平坦フィルム４０ａと、凹凸フィルム４０ｂとが貼り合わされて凸部４１が形成されており、平坦フィルム４０ａと凹凸フィルム４０ｂとの両者の間には、凸部４１の内部に空気室４０ｃが形成されている。
【００５８】
このように、かかるフィルム成形体を、無数の振動体が固定された板状遮音体の少なくとも一方の面に積層することによって、騒音を改善し得る低周波数域を広くすることができる。
【００５９】
さらに、このフィルム成形体の凸部間には、図１１に示す防音材３７′のように、緩衝材４２を設けることができる。かかる緩衝材としては、架橋粘弾性体及び発泡型架橋粘弾性体の一方又は双方を用いることができる。かかる緩衝材を、フィルム成形体の凸部間に介在させることによって、振動体付き板状遮音体や吸音材では克服困難な、２５０〜５００Ｈｚの中周波数域の防音性能をより一層向上させることができる。
【００６０】
このように、本発明の防音材によれば、振動体や板状遮音体の材質や配置を調節することによって、防音し得る周波数を低周波数から高周波数までの広範囲にわたって調整することができる。
【００６１】
特に、本発明では、板状遮音体の面密度、張力を変化させることにより、低周波数及び高周波数での周波数の調整、遮音量の調整ができる。また、本発明においては、振動体の質量、配置間隔を調節することによって、改善し得る周波数の調整、遮音量の調整ができる。
【００６２】
また、本発明では、吸音材を組合せた防音材とすることで、遮音量を増加させることができ、さらに、吸音層厚を増すことにより、改善し得る周波数を中周波数域まで調整することができる。
【００６３】
更に、本発明では、空気室を有するシート、空気室の周囲に粘弾性体を設けたシートを組み合わせた防音材とすることによって、中周波数域の性能の落ちこみを防止することもできる。
【００６４】
本発明の防音材は、構築物の壁、天井、パイプスペース、空調ダクトや給排水管の外周、車輛、船舶、航空機等の騒音防止が要求される多くの利用分野で、防音用途に適用することができる。特に、本発明によれば、所望の周波数帯域の騒音を対策する際に、軽くて、省スペースで、低コストの防音材を提供し得る。
【００６５】
【実施例】
以下、図面を参照して、本発明を実施例及び比較例に基づいて、より一層具体的に説明する。図１２は、防音材の透過損失を測定する残響室の平面図である。図１３（ａ）は、本発明の一参考例の防音材の部分縦断面図である。図１３（ｂ）は、図１３（ａ）の防音材の平面図である。図１４（ａ）は、本発明の他の参考例の防音材の部分縦断面図である。図１４（ｂ）は、図１４（ａ）の防音材の平面図である。図１５は、比較例の一例の防音板の部分縦断面図である。
【００６６】
参考例１
図１（ａ）及び（ｂ）に示す防音材を製造した。板状遮音体としては、非加硫ブチルゴムシート（２ｍｍ厚）を用い、振動体としては、比重１．７５の５ｍｍ厚ブチルゴムシートを３０ｍｍ角に切断したものを用いた。振動体１個の質量は７．９ｇとした。
【００６７】
次に、図１（ｂ）に示すように、非加硫ブチルゴムシートに３０ｍｍ間隔で縦横に罫線を入れた。１５０ｍｍ角の範囲で、振動体を四隅と中央の５箇所に配置した。この際、振動体の重心間距離が１２０ｍｍとなるように、振動体をブチル粘着剤で貼り付けた。
【００６８】
このようにして得た防音材を供試体とし、図１４に示す残響室４３において、防音性能を試験した。残響室４３は、２つの部屋４３ａ，４３ｂに分かれており、それぞれに、防音ドア４４ａ，４４ｂ、スピーカ４５ａ，４５ｂ、マイク４６ａ，４６ｂが備えられている。２つの部屋４３ａ，４３ｂの間には、９．５ｍｍ厚の石膏ボード４７が設けられている。
【００６９】
試験では、石膏ボード４７上に、供試体の板状遮音体側の面を取り付けて、５０Ｈｚ〜５０００Ｈｚの周波数について透過損失を測定した。測定には、ＪＩＳ−Ａ−１４１６−１９７４に従う、実験室における音響透過損失測定方法を用いた。但し、ＪＩＳ−Ａ−１４１７では、原則として、試験は、１２５Ｈｚ〜４０００Ｈｚの１６周波数の１／３オクターブ中心周波数で行われるが、この試験では、低周波及び高周波の騒音の改善をも目的としているため、１／３オクターブ中心周数で５０〜１００Ｈｚ及び５０００Ｈｚも測定範囲に入れた。結果を表１に示した。
【００７０】
参考例２
図１３（ａ）及び（ｂ）に示す防音材４８を製造した。振動体４９としては、比重１．７５の６ｍｍ厚ブチルゴムシートを１０ｍｍ角に切断して用いた。板状遮音体５０としては、非加硫ブチルゴムシート（２ｍｍ厚）を用いた。振動体１個の質量は１．１ｇとした。
【００７１】
次に、図１３（ｂ）に示すように、板状遮音体５０に１５ｍｍ間隔で縦横に罫線を入れ、振動体４９を、罫線の交点上に重心間距離が１５ｍｍとなるように配置し、ブチル粘着剤で貼り合わせて防音材４８を製造した。この防音材を供試体として、参考例１と同様に石膏ボード上に取り付け、透過損失を測定した。結果を表１に示した。
【００７２】
参考例３
図１４（ａ）及び（ｂ）に示す防音材５１を製造した。振動体５２としては、８．５ｍｍ厚の磁器タイル（９４ｍｍ角）で、１個の質量が１５７ｇのものを用いた。板状遮音体５３としては、非加硫ブチルゴムシート２ｍｍ厚を用いた。振動体５２を、その重心間距離を３００ｍｍとなるように、ウレタンコーキングで貼り付け、防音材５１を製造した。この防音材を供試体として、参考例１と同様に石膏ボード上に取り付けて、透過損失を測定した。結果を表１に示した。
【００７３】
参考例４
図４（ａ）及び（ｂ）に示す防音材を製造した。板状遮音体１３としては、１ｍｍ厚のＥＶＡシートを使用した。振動体１２としては、２ｍｍ厚のポリエチレン２０倍発泡シート１２ｂと、５ｍｍ厚の磁器タイル１２ａ（２５ｍｍ角）を用いた。ポリエチレン２０倍発泡シート１２ｂの両面にアクリル粘着剤を塗布し、シート１２ｂの上面に磁器タイル１２ａを張り付け、ポリエチレン２０倍発泡シート１２ｂ下面に離型紙を貼り合わせて、タイル１２ａを１個づつに切り離し、振動体１２とした。振動体１個の質量は６．６ｇである。
【００７４】
図４（ｂ）に示すように、１ｍｍ厚のＥＶＡシートに、振動体の重心間距離が１００ｍｍとなるようにして、ポリエチレン２０倍発泡シート面をＥＶＡに貼り付けることで、防音材を製造した。この防音材を供試体として、参考例１と同様に石膏ボートに取り付け、透過損失を測定した。その結果を表１に示した。
【００７５】
参考例５
図２（ａ）及び（ｂ）に示す防音材４を製造した。振動体５と板状遮音体６とは、両側に凸部を有するプレス加硫ゴムシートとして作製した。ゴムシート部の厚みは２ｍｍで、上下の凸部は、図２（ａ）に示すように、同一部分の上下にくるようにした。凸部は、直径１０ｍｍ、高さ１０ｍｍの円柱状となっており、振動体として機能する。シート部も振動体部も同一の天然ゴムＳＢＲブレンドゴムとし、比重は２．２０とした。振動体の配置は、図２（ｂ）に示すように、振動体の重心間隔を４０ｍｍとした。振動体は、上下両方を１個とみなし、３．５ｇ／個とした。この防音材を、参考例１と同様にして、石膏ボードに取り付け透過損失を測定した。その結果を表１に示した。
【００７６】
参考例６
図５（ａ）及び（ｂ）の防音材を製造した。振動体と板状遮音体としては、片側に凸部を有するプレス加硫ゴムシートを２枚重ね合わせて作製した。１枚のゴムシート部の厚みは１ｍｍで、凸部は、直径１０ｍｍ、高さ１０ｍｍの円柱状であり、振動体として働く。シート部も振動体部も同一の天然ゴム／ＳＢＲブレンドゴムから作製し、比重は２．２０とした。振動体は、重心間隔を４０ｍｍとして設けた。振動体の質量は１．８ｇ／個とした。
【００７７】
このシート２枚を、一方の面の振動体と残る一方の面の振動体とで、振動体の重心間隔が２０ｍｍとなるようにして、貼り合わせ、図５（ｂ）に示すような、両面に凸部があり、上下面の凸部が重ならない防音材を製造した。この防音材を供試体とし、参考例１と同様にして、石膏ボードに取り付けて透過損失を測定した。その結果を表１に示した。
【００７８】
参考例７
参考例１に用いた防音材の振動体の反対面に、１０ｍｍ厚の不織布を設け、図７（ａ）及び（ｂ）に示す防音材を製造した。この防音材の不織布側を石膏ボードに取り付けて、参考例１と同様にして透過損失を測定した。結果を表１に示した。
【００７９】
参考例８
参考例１に用いた防音材の振動体の反対面に、２ｍｍ厚の不織布を設け、図８（ａ）及び（ｂ）に示す防音材を製造した。この防音材の不織布側を石膏ボードに取り付けて、参考例１と同様に透過損失を測定した。結果を表１に示した。
【００８０】
参考例９
参考例１に用いた防音材の振動体の反対面に、平坦なフィルムと凹凸加工されたフィルムの２枚のフィルムで空気室を無数に設けた、４ｍｍ厚の凹凸シートを設け、図１０に示す防音材を製造した。この防音材の凹凸フィルム側を石膏ボードに取り付けて、参考例１と同様にして透過損失を測定した。結果を表１に示した。
【００８１】
【表１】

【００８２】
参考例１０
参考例９に用いた防音材の凹凸シートの凹部に、常温硬化反応型弾性体を設けて、図１１に示す防音材を製造した。この防音材を供試体として、参考例１と同様に透過損失を測定した。結果を表２に示した。
【００８３】
実施例１
図６に示す防音材を製造した。参考例１で使用した防音材の板状遮音体の周辺部を、厚さ１２ｍｍ、幅２０ｍｍの合板からなる枠材２３と、厚さ３ｍｍ、幅２０ｍｍの合板２４とで挟み、タッカー釘２５で止め、板状遮音体に張力を与え、張りをもたせた。この防音材を、石膏ボードに取り付け、参考例１と同様に透過損失を測定し、その結果を表２に示した。
【００８４】
参考例１１
図３（ａ）及び（ｂ）に示すような防音材を製造した。但し、この例の防音材では、振動体側に高比重成分が偏在するように比重勾配を形成し、板状遮音体側には高比重成分が局在しないようにした。
【００８５】
鉄粉、タングステン粉、硅砂等の高比重大粒径充填剤とタルク、マイカ等の中比重小粒径充填剤と、ガラスバルーン等の低比重大粒径充填剤を混合して得た可撓性エポキシを型に流し、図３（ａ）に示すような防音材を作製した。この防音材は、図３（ｂ）に示すように、振動体として働く凸部の上面側が高比重となるような比重勾配を有する。この防音材の振動体は、１個の質量が２．３ｇで、振動体の重心間距離は１０ｍｍである。この防音材を石膏ボードに取り付け、参考例１と同様に透過損失を測定した。結果を表２に示した。
【００８６】
参考例１２
図９に示す防音材を製造した。板状遮音体としては、１０ｍｍ角の網を用い、それに振動体として、２５ｍｍ厚の磁器タイル（１個の質量６．６ｇ）をホットメルト接着剤で取り付けた。振動体の重心間隔は３０ｍｍとした。これを１５ｍｍ厚の目付量１．６ｋｇ／ｍ^２の不織布と、２０ｍｍ厚の目付量７００ｇ／ｍ^２の不織布の間にはさみ、防音材を作製した。この防音材を石膏ボードに取り付け、参考例１と同様に透過損失を測定した。結果を表２に示した。
【００８７】
比較例１
９．５ｍｍ厚の石膏ボードについて、参考例１と同様に透過損失を測定した。結果を表２に示した。
【００８８】
比較例２
比較例１の石膏ボードに２ｍｍ厚の非加硫ブチルゴムシートを取り付け、参考例１と同様に透過損失を測定した。結果を表２に示した。
【００８９】
比較例３
図１５に示すように、２ｍｍ厚の非加硫ブチルゴムシート５４に、１０ｍｍ厚の不織布５５を貼り付けて防音板５６を作製した。この防音板５６の不織布５５側を石膏ボードに取り付けて、参考例１と同様に透過損失を測定した。結果を表２に示した。
【００９０】
【表２】

【００９１】
表１及び２に示す測定値に基づいて、実施例及び比較例を説明する。
参考例１は、板状遮音体を２ｍｍ厚の非加硫ブチルゴムシートとし、振動体をブチルゴム５ｍｍ厚、３００ｍｍ角とし、７．９ｇ／個の質量とし、振動体の重心間隔を１２０ｍｍとし、石膏ボードに取り付けた例である。石膏ボード９．５ｍｍ厚に非加硫ブチルゴムシートを取り付けた比較例２と比べ全周波数域で改善されているが、中でも５０〜８０Ｈｚの改善し難い帯域で改善されている。比較例２では、比較例１（石膏ボード）の４ｋＨｚコインシデンスの落ち込みを大きく改善しているものの、若干の落ち込みが見られるが、参考例１では落ち込みは見られないし、改善量も大である。
【００９２】
参考例２は、参考例１の板状遮音体を用いて、振動体を１．１ｇ／個と軽くし、振動体の重心間距離を１５ｍｍと狭くした例である。５０〜８０Ｈｚの帯域の改善量は少なくなるものの、比較例２と比べ２ｋＨｚ以上の帯域では大きな改善が見られる。参考例１よりも軽いにもかかわらず２ｋＨｚ以上は改善量が大である。
【００９３】
参考例３は、参考例１の板状遮音体を用いて、振動体を１５７ｇ／個と重く、振動体の重心間距離も３００ｍｍと広くした例である。５０〜１００Ｈｚの帯域では非常に大きな改善量を示している。逆に２００〜６３０Ｈｚでは比較例２よりも悪化する部分も生じている。３．１５ｋＨｚ以上は、参考例１とほぼ同等となっている。
【００９４】
参考例４は、板状遮音体に面密度の低いＥＶＡシート１ｍｍ厚を使用し、振動体とＥＶＡシートの間にポリエチレン発泡シート２ｍｍ厚を介して、６．６ｇ／個の振動体を重心間距離１００ｍｍとして設けた例である。５０〜６３Ｈｚでは明らかに防音効果が見られる。非加硫ブチルゴムシート２ｍｍ厚よりも面密度が低いにもかかわらず、１２５Ｈｚ〜１．２５ｋＨｚでは、ほとんど比較例２と同等の性能である。また、１．６ｋＨｚ〜５ｋＨｚでは、比較例２より若干劣るものの、比較例１の石膏ボードより大幅な改善を示している。これは軽量でありながら改善効果を挙げる上で有効なことを示している。
【００９５】
参考例５は、板状遮音体と振動体を比重２．２の同一素材とし、２ｍｍ厚の板状遮音体の両側に振動体が同じ位置にあるものであり、振動体の質量が３．５ｇ／個で、振動体の重心間距離を４０ｍｍとした例である。５０〜８０Ｈｚでの改善量が大で、比較例２と比べ、特に１．６ｋＨｚ以上での改善効果が大きい。
【００９６】
参考例６は、板状遮音体として１ｍｍ厚の板状遮音体と振動体を比重２．２の重一素材として形成し、片面上に振動体を設けた２枚のシートを、振動体が同じ位置にこないようにずらして貼り合わせ、２ｍｍ厚の板状遮音体とした例で、振動体の質量が１．８ｇ／個、振動体の重心間隔４０ｍｍとした例である。５０〜２５０Ｈｚの低周波で効果が大であり、１ｋＨｚ以上の改善量は非常に高い。
【００９７】
参考例７は、参考例１の振動体の反対面に不織布厚１０ｍｍを取り付けた例である。非加硫ブチルゴム２ｍｍ厚に不織布１０ｍｍ厚を取り付けた比較例３と比べても、５０〜１２５Ｈｚでの改善量は大きい。２００〜５００Ｈｚでは、比較例３よりも悪化し、２００〜４００Ｈｚでは、比較例２よりも悪化するものの、８００Ｈｚ以上の帯域での改善効果は目を見はるものがある。
【００９８】
参考例８は、参考例７の不織布を２ｍｍ厚に変えた例である。５０〜１２５Ｈｚでは、比較例３よりも大きく改善できている。２００〜１ｋＨｚでは、比較例より悪化する部分はあるものの、１．６ｋＨｚ以上では、非常に大きな改善効果がある。
【００９９】
参考例９は、参考例７及び８の不織布を空気室を無数に有する凹凸シート厚４ｍｍに変えた場合である。５０〜６３Ｈｚの改善ができており、特に１００Ｈｚ〜３１５Ｈｚの改善ができる点は他にない傾向である。５００Ｈｚ〜８００Ｈｚでは、比較例３よりも悪化しているものの、他の全帯域では大きく改善できている。
【０１００】
参考例１０は、参考例９の凹凸シートの凸部空気室の周囲に架橋粘弾性体を形成させた例である。全周波数帯域で、比較例３のものを改善できており、特に８０〜４００Ｈｚでの改善効果は大きく、２０ｋＨｚ以上の改善も大きい。
【０１０１】
実施例１は、参考例１の板状遮音体の周囲に張力補強のための枠材を設けた例である。５０〜８０Ｈｚでは、非常に改善量が大である。２００〜６３０Ｈｚでは、逆に比較例２よりも悪化しているが、８００Ｈｚ以上では非常に大きな改善を示している。
【０１０２】
参考例１１は、比重が高・中・低の充填剤を混入して硬化させた比重勾配を有するシートと振動体を設けた可撓性エポキシシートで、振動体の質量を２．３ｇ／個、振動体の重心間距離を１０ｍｍとした例である。５０〜１６０Ｈｚでは、比較例２と比べ改善量は大である。８００Ｈｚ以上での改善量も大で、４ｋＨｚでの落ち込みも見られない。この例では、全周波数で大きく落ち込む所がない点が有利である。
【０１０３】
参考例１２は、板状遮音体として網を用い、振動体として磁器タイルを用いたものを、１５ｍｍ厚で１．６ｋｇ／ｍ^２の目付の不織布と２０ｍｍ厚で０．７ｋｇ／ｍ^２の目付の不織布ではさんだ例である。この振動体の質量は６．６ｇ／個で、振動体の重心間距離は３０ｍｍである。５０Ｈｚと６３Ｈｚでは、大きな改善が見られ、２ｋＨｚ以上では、石膏ボード特有のコインシデンス効果による性能低下が見られ、また、４ｋＨｚで若干の落ち込みはあるものの、２ｋＨｚ以上では良好である。
【０１０４】
比較例１は、石膏ボード単体であり低周波側での落ち込みと、２ｋＨｚ以上のコインシデンス効果による落ち込みが見られる。
【０１０５】
比較例２は、比較例１に非加硫ブチルゴムシート２ｍｍ厚を取り付けた例である。本実施例の振動体付きシートとの比較に使用した。
【０１０６】
比較例３は、比較例２の非加硫ブチルゴムシート２ｍｍ厚と石膏ボードの間に１０ｍｍ厚不織布を取り付けた例である。本実施例の不織布や凹凸シートを振動体付き板状遮音体と石膏ボードの間に入れた例との比較に用いた。
【０１０７】
以上のように、板状遮音体に振動体を設けた防音材は、改善量の大小の差はあるものの、振動体のない比較例２及び３と比べ、何れも５０Ｈｚ〜８０Ｈｚの帯域で防音効果が高い。特に大きな効果が得られるものは、参考例３の重い振動体を用い例と、実施例１の板状遮音体の張力を保持した例と、参考例１２の振動体を付けた網を不織布ではさんだ例である。
【０１０８】
１００〜１５０Ｈｚ帯域での騒音改善効果の大きいものとしては、参考例９の空気室を有する凹凸シートを用いた例と、参考例１０の凸部空気室の周囲の凹部に架橋粘弾性体を設けた例を挙げることができる。
【０１０９】
参考例７及び８の不織布を用いた防音材では、低周波の改善帯域が５０〜１２５Ｈｚと広くなる傾向がある。また、厚みを薄くすることにより、高周波側の改善効果の有効周波数がより低い周波数に移行し、その改善効果は極端に大きくなる。参考例５及び６からわかるように、両側に振動体を有する場合には、振動体位置を片側にずらせる事で５０〜６３Ｈｚで２ｄＢ程度改善量を増し、１２５０Ｈｚ以上で１〜４ｄＢ改善量を増すことができる。何れの実施例も高周波側の改善効果は非常に高くなっている。
【０１１０】
【発明の効果】
本発明の防音材によれば、所定の材質の板状遮音体上に、点状に設けられた無数の振動体が振動することによって、防音対象としての発音体の低周波の騒音を著しく改善することができる。
【０１１１】
また、本発明の防音材によれば、振動体や板状遮音体の材質や配置を調節することによって、防音し得る周波数を低周波数から高周波数までの広範囲にわたって調整することができる。
【図面の簡単な説明】
【図１】（ａ）は、本発明の一参考例の防音材の部分縦断面図である。（ｂ）は、（ａ）の防音材の平面図である。
【図２】（ａ）は、本発明の他の参考例の防音材の部分縦断面図である。（ｂ）は、（ａ）の防音材の平面図である。
【図３】（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。（ｂ）は、（ａ）の防音材の部分拡大縦断面図である。
【図４】（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。（ｂ）は、（ａ）の防音材の平面図である。
【図５】（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。（ｂ）は、（ａ）の防音材の平面図である。
【図６】本発明の一例の防音材の縦断面図である。
【図７】（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。（ｂ）は、（ａ）の防音材の平面図である。
【図８】（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。（ｂ）は、（ａ）の防音材の平面図である。
【図９】本発明の更に他の参考例の防音材の縦断面図である。
【図１０】本発明の更に他の参考例の防音材の部分縦断面図である。
【図１１】本発明の更に他の参考例の防音材の縦断面図である。
【図１２】防音材の透過損失を測定する残響室の平面図である。
【図１３】（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。（ｂ）は、（ａ）の防音材の平面図である。
【図１４】（ａ）は、本発明の更に他の参考例の防音材の部分縦断面図である。（ｂ）は、（ａ）の防音材の平面図である。
【図１５】比較例の一例の防音板の部分縦断面図である。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a soundproofing material attached to the outside of a sounding body to reduce noise of the sounding body.
[0002]
[Prior art]
Conventionally, various measures have been taken for soundproofing by using soundproofing materials, sound absorbing materials, vibration damping materials, and vibration damping materials. In recent years, in particular, there has been no situation in which no soundproofing measures have been taken at all, especially for living spaces of people.
[0003]
On the other hand, the sound is very difficult to make it completely empty, so when a certain sound source is improved, the sound source is masked by that sound source, and the sound source that you do not care about begins to be concerned. There are properties and situations. For this reason, in terms of technical and permissible costs, it is required to provide a lighter, cheaper, and space-saving soundproofer. In technical terms, a soundproofing material that is effective in a low frequency range is required.
[0004]
[Problems to be solved by the invention]
Conventionally, a sound insulating material having a high surface density, which has been used in many scenes, has a drop in soundproofing performance at a low frequency. This drop cannot be prevented unless the thickness of the sound insulating material is increased by a considerable amount, and is practically impossible in terms of weight increase and cost. On the other hand, such a sound insulating material generally has a performance drop due to a coincidence effect on the high frequency side, and it is hard to say that the sound insulating material alone is sufficient.
[0005]
In order to prevent such performance deterioration on the low frequency side and the high frequency side, a sound absorbing material is used. However, if a sound absorbing material having a thickness of 1 m or more can be used, it is almost impossible to use such a bulky space in consideration of a normal living space for people. Therefore, it is extremely difficult to take measures against low-frequency or high-frequency noise with a sound insulating material or a sound absorbing material.
[0006]
At present, there is a method of taking measures against a vibration source that generates low-frequency sound or a sound source itself. However, in reality, there is no known method for effectively preventing low-frequency noise generated once, such as heavy floor impact noise.
[0007]
In addition, harsh high-frequency sounds need to be improved by some countermeasures in terms of soundproofing measures, but there is no known easy and low-cost method for adjusting such high-frequency sounds to a target volume at low cost. There are many expectations for measures against high-frequency sounds.
[0008]
An object of the present invention is to obtain a soundproofing material effective for low-frequency noise. Another object of the present invention is to obtain a soundproofing material that can control a frequency that can be improved and that is effective for noise in a wide range of frequencies.
[0009]
[Means for Solving the Problems]
The present invention is a soundproofing material attached to the outside of a sounding body and reducing noise of the sounding body, wherein the soundproofing material includes a plurality of vibrators and a plate-like sound insulator supporting each of the vibrators. The plate-like sound insulator is a sheet or film using various rubbers, polymers, and rubber asphalts alone or in combination, a nonwoven fabric, or a felt alone or in combination, and each vibrator is at least one side of the plate-like sound insulator. The vibrating body is fixed at a predetermined interval from each other, and a peripheral portion of the plate-shaped sound insulating body is bent and pulled by a frame material, and the frame material is fixed to the plate-shaped sound insulating body. The sound-insulating material according to the present invention is characterized in that the vibrating body vibrates due to radiation sound of the sounding body, while maintaining body tension.
[0010]
The present inventor has made various trials of various soundproofing materials and studied them in detail in order to obtain a lightweight, space-saving, and low-cost soundproofing material that is effective for low-frequency noise.
[0011]
As a result, the present inventor has found that a plurality of vibrators are fixed on at least one surface of a predetermined plate-shaped sound insulator, and the low-frequency noise is efficiently reduced by the soundproofing material in which the respective vibrators are separated from each other at a predetermined interval. As a result, the present inventors have found that the present invention can be improved.
[0012]
In addition, the present inventor has noted that such a soundproofing material can control mid- and high-frequency noise while reducing low-frequency noise by various means, and can reduce noise in a wide range of frequencies. After confirming the facts to be performed, the present invention has been completed.
[0013]
The present inventors have not fully clarified the mechanism by which the soundproofing material of the present invention reduces low-frequency noise. By analogy with various tests performed by the inventor and the results thereof, in the present invention, a plurality of vibrators fixed to the plate-shaped sound insulator vibrate by low-frequency sound by themselves, and this vibration is generated by the plate-shaped sound insulation. It is considered that low frequency noise is absorbed by being attenuated by body tension.
[0014]
High-frequency sound has a short wavelength and low energy, so it is relatively easy to isolate sound.However, in the present invention, high-frequency sound can be reduced even if the surface density of the plate-like sound insulator is low, and the soundproofing material can be further improved. Lightening is possible. On the other hand, low-frequency sound has a long wavelength and a large energy. Therefore, if the sound is to be isolated according to the mass rule, the weight increases and it is difficult to completely prevent the sound.
[0015]
In the present invention, the plurality of vibrators are exposed to the vibration by the sound waves, and efficiently cause energy loss of sound. In this way, the soundproofing material of the present invention reduces noise and works effectively especially in a low frequency region.
[0016]
According to the present invention, a sheet, a film, a cloth, a plate-like sound insulator such as a net-like object, by adopting a structure in which countless vibrators are provided in a dot-like manner, a low-frequency sound generator as a soundproofing target. Noise can be significantly improved.
[0017]
Further, according to the soundproofing material of the present invention, the frequency that can be soundproofed can be adjusted over a wide range from a low frequency to a high frequency by adjusting the material and arrangement of the vibrating body and the plate-shaped sound insulating body.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention will be described in detail with reference to the drawings.
FIG. 1A is a partial longitudinal sectional view of a soundproofing material according to a reference example of the present invention. FIG. 1B is a plan view of the soundproofing material of FIG. FIG. 2A is a partial longitudinal sectional view of a soundproof material according to another reference example of the present invention. FIG. 2B is a plan view of the soundproofing material of FIG. 2A. FIG. 3A is a partial longitudinal sectional view of a soundproof material according to still another reference example of the present invention. FIG. 3B is a partially enlarged longitudinal sectional view of the soundproofing material of FIG. 3A. FIG. 4A is a partial longitudinal sectional view of a soundproof material according to still another reference example of the present invention. FIG. 4B is a plan view of the soundproofing material of FIG. FIG. 5A is a partial longitudinal sectional view of a soundproof material according to still another reference example of the present invention. FIG. 5B is a plan view of the soundproofing material of FIG.
[0019]
FIG. 6 is a longitudinal sectional view of a soundproofing material according to an example of the present invention. FIG. 7A is a partial longitudinal sectional view of a soundproof material according to still another reference example of the present invention. FIG. 7B is a plan view of the soundproofing material of FIG. FIG. 8A is a partial longitudinal sectional view of a soundproofing material of still another reference example of the present invention. FIG. 8B is a plan view of the soundproofing material of FIG. 8A. FIG. 9 is a longitudinal sectional view of a soundproof material according to still another reference example of the present invention. FIG. 10 is a partial longitudinal sectional view of a soundproof material according to still another reference example of the present invention. FIG. 11 is a longitudinal sectional view of a soundproof material according to still another reference example of the present invention.
[0020]
FIGS. 1 to 11 show a soundproof material according to a reference example and an example of the present invention which is attached to the outside of a sounding body and reduces noise of the sounding body. The soundproof material 1 shown in FIG. 1 includes a plurality of vibrators 2 and a plate-like sound insulator 3 that supports each of the vibrators 2. Each of the vibrators 2 is fixed on at least one surface of the plate-like sound insulator 3. Each vibrating body 2 is separated from each other at a predetermined interval, and each vibrating body 2 vibrates due to radiation sound of the sounding body.
[0021]
A plate-like sound insulator according to the present invention supports and fixes a vibrator. Such a plate-shaped sound insulator may be any as long as it can fix and support the vibrating body and vibrate as a whole or partially by the vibrating body. Depending on what kind of soundproofing performance it is desired to obtain as a whole, the allowable range of cost, and the allowable range of weight and space, such a plate-shaped sound insulator does not necessarily have to have a high surface density. The effect of the reduction can be exhibited.
[0022]
For such a plate-shaped sound insulator, sheets or films of various rubbers, polymers, and rubber asphalts alone or in combination, meshes, woven fabrics, nonwoven fabrics, and those in which felts are used alone or in combination are not particularly limited. .
[0023]
The vibrating body according to the present invention is not particularly limited in material and the like, but may be determined by referring to the following specific examples based on target performance, installation space, cost, and the like. Specific examples thereof include the use of inorganic substances such as tiles, cement, gypsum, and glass, and metals and alloys such as lead, iron, copper, and stainless steel, and the use of organic substances such as rubber and polymers alone or in combination. Can be used.
[0024]
In the reference example of the present invention, a soundproof material 4 as shown in FIGS. 2A and 2B is included. In this soundproofing material 4, the vibrating body 5 and the plate-like sound insulating body 6 are formed of the same or the same material. In this case, as shown in FIG. 2A, the vibrating body 5 is formed as a protruding portion protruding from the plate-shaped sound insulating body so as to be easily susceptible to vibration and swinging.
[0025]
In the soundproofing material of the present invention, a vibrating body or a plate-like sound insulating body can be formed from two or more kinds of components having different specific gravities. For example, it can be molded from a mixture of a crushed product of rubber or polymer and a high specific gravity material such as metal powder, metal oxide powder, and sand. Further, in such a soundproofing material, a vibrating body as shown in FIGS. 2A and 2B may be formed as a projection on the surface at the same time as molding the plate-like soundproofing body.
[0026]
In such a case, at least one of the vibrating body and the plate-shaped sound insulator is made of two or more components having different specific gravities, and when the soundproofing material is viewed in a cross section perpendicular to the plane of the plate-shaped sound insulator, A component having a high specific gravity can be formed so as to be biased.
[0027]
One example of such a soundproofing material is shown in FIGS. As shown in FIG. 3B, the soundproof material 7 causes a specific gravity gradient in the soundproof material 7 due to the uneven distribution of the heavy component 9 on the surface side of the vibrating body 8. In the soundproof material 7, the vibrating body 8 is easily vibrated, and the noise on the low frequency side is more easily reduced.
[0028]
Such a vibrating body can be formed so as to have a specific gravity gradient in a cross-section thereof by rotational molding or specific gravity difference sedimentation molding using a high specific gravity powder and a liquid polymer.
[0029]
In the vibrating body having such a specific gravity gradient, a specific gravity gradient can be provided not only to the vibrating body shown in FIG.
[0030]
In the soundproofing material 7 as shown in FIGS. 3A and 3B as an example, the plate-like sound insulating body 10 also includes the heavy component 9 like the vibrator 8. 9 is localized on the surface side of the plate-shaped sound insulator 10.
[0031]
Such a soundproofing material exhibits excellent soundproofing performance without any significant decrease in performance in any of the low, middle, and high frequency ranges. This is considered to be due to the fact that the vibrating body is deflected to the center of gravity, resulting in a larger amplitude, and the vibrating body is fixed to the plate-like sound insulating body, and the energy loss due to vibration increases.
[0032]
Further, in the present invention, it is possible to obtain a soundproofing material in which such a vibrating body is composed of two or more different layers as shown in FIGS. 4 (a) and 4 (b). In this soundproof material 11, the vibrating body 12 is composed of an upper layer 12 a and a lower layer 12 b, and the lower layer 12 b is fixed to the plate-like sound insulator 13.
[0033]
As the lower layer, for example, if a vibrating body is formed in a form of two or more layers through an easily deformable material such as a foam or a nonwoven fabric, or an adhesive material such as a viscoelastic body, the vibration of the vibrating body can be improved. Behavior can be adjusted.
[0034]
Such a vibrating body can adjust the frequency at which the vibrating body itself or the plate-shaped sound insulating body vibrates, and can fine-tune the frequency band of the noise to be improved.
[0035]
In the present invention, the respective vibrators can be provided at various intervals so that noise at a predetermined low frequency is reduced. The frequency range that can be improved can be shifted by adjusting the distance between the centers of gravity of the vibrators. By combining a plurality of mounting intervals of each vibrating body, a frequency band that can be improved can be set widely.
[0036]
For example, it is preferable that the distance between the centers of gravity of the respective vibrators is 5 to 300 mm without overlapping the respective vibrators. In particular, 10 to 150 mm is more preferable. When the distance between the centers of gravity of the vibrators is less than 5 mm, the effect of improving the low-frequency noise obtained by vibrating each vibrator is reduced. In such a case, such a problem can be solved by adding a special measure such as providing a large specific gravity gradient between the vibrating body and the plate-shaped sound insulating body. Conversely, if the distance between the centers of gravity of the vibrators exceeds 300 mm, it is difficult to reduce noise on the high frequency side, and the frequency that can be reduced is limited to 2 kHz or more.
[0037]
The shape of the vibrator may be cylindrical, spherical, hemispherical, cubic, rectangular, or any other shape. The mass of the vibrator is preferably 1 to 200 g / piece. A particularly preferred range is from 1 to 30 g. When the mass is less than 1 g / piece, there is a tendency that noise in a low frequency range is particularly difficult to be reduced. Conversely, if the mass exceeds 200 g / piece, it is good for noise reduction in the low frequency range, but it is not practical because the weight of the soundproofing material is too large and the usable scene is limited.
[0038]
In the present invention, when the vibrating body and the plate-shaped sound insulating body are not integrally formed, they can be fixed using various means and methods to provide a soundproofing material. For example, a method of attaching with an adhesive or an adhesive or physically fixing with a tucker or a stapler may be used. A plurality of vibrators having various shapes and masses made of various materials may be mixed and used, or each vibrator may be attached at various intervals.
[0039]
In the present invention, the vibrating body can be further easily vibrated by bonding or fixing the vibrating body to the plate-shaped sound insulating body via a viscoelastic body or a foam.
[0040]
Such vibrators may be provided not only on one side but also on both sides of the soundproofing material. In this case, a separation portion is formed between one of the vibrators disposed on one surface of the plate-shaped sound insulator, and the other vibration disposed on the other surface of the plate-shaped sound insulator. Preferably, the body is arranged such that it is located above the separation.
[0041]
The soundproofing material of this example is shown in FIGS. As shown in FIG. 5 (a), the soundproof material 14 includes an upper vibrating body 15 and a lower vibrating body 16 provided alternately on an upper plate-shaped sound insulator 17 and a lower plate-shaped sound insulator 18, respectively. I have. Further, as shown in FIG. 5B, the upper vibrating bodies 15 are provided at predetermined intervals, and a separation portion 19 is formed between each. The lower vibrating body 16 is located below the separating portion 19.
[0042]
As described above, when the positions of the vibrating bodies on both sides are not the same, and when the positions are slightly shifted on both sides, the amount of improvement at 50 to 63 Hz is good, and the amount of improvement at high frequencies is good. With such a configuration, the phase of the vibration of the vibrating body is shifted and energy loss is likely to occur, so that it is considered that the soundproofing effect is enhanced.
[0043]
In the present invention, a frame member is provided on the plate-shaped sound insulator, and the frame member holds the tension of the plate-shaped sound insulator. Such a soundproofing material can control the noise frequency that can be improved by effectively using the tension of the plate-like soundproofing material.
[0044]
FIG. 6 shows an example of such a soundproof material. This soundproofing material 20 includes a vibrating body 21 and a plate-shaped sound insulating body 22, and each of the vibrating bodies 21 is disposed on the plate-shaped sound insulating body 22, as shown in FIG. The peripheral portion 22 a of the plate-shaped sound insulator 22 is bent, and is pulled in the peripheral direction by the frame member 23. The peripheral portion 22a of the plate-shaped sound insulator 22 is sandwiched between a frame member 23 and a fixing member 24 such as plywood, and is fastened using nails 25.
[0045]
There are no particular restrictions on the material, shape, etc., of the frame material according to the present invention as long as it can continuously apply tension to the plate-like sound insulator. For example, a frame made of a wooden material, a metal frame made of iron, stainless steel, aluminum, or the like can be used.
[0046]
Such a frame material is provided on the outer periphery of the plate-shaped sound insulator, and if necessary, a portion surrounded by the frame is provided with a reinforcing material in the shape of a cross, and the area where the tension of the plate-shaped sound insulator is applied is divided. Good. By applying tension to the plate-shaped sound insulator with the frame material, the noise reduction of the soundproof material in the low frequency range can be further increased.
[0047]
Such a plate-shaped sound insulator can adjust the amount of improvement particularly in the low frequency range of 63 to 125 Hz, and can increase the amount of improvement.
[0048]
Furthermore, in the present invention, by attaching a sound absorbing material to at least one surface of the plate-shaped sound insulating body on which countless vibrating bodies are fixed, the high-frequency sound of the sounding body as a soundproofing target can be significantly improved.
[0049]
Examples of such a soundproofing material are shown in FIGS. 7A and 7B, a sound absorbing material 29 is provided on one surface of a plate-shaped sound insulating body 28 opposite to the vibrating body 27.
[0050]
In addition, such a sound absorbing material can significantly improve the soundproofing performance by providing a relatively thin sound absorbing material 31 like the sound insulating material 30 shown in FIG.
[0051]
Further, as such a soundproofing material, as in a soundproofing material 32 shown in FIG. 9, a sound absorbing material 35 and a sound absorbing material 36 can be arranged on the upper surface of the vibrating body 33 and the lower surface of the plate-like sound insulating body 34.
[0052]
In this way, if the plate-shaped sound insulator is sandwiched with a sound absorbing material or a sound absorbing material is laminated on one side, the frequency range of noise that can be improved is shifted, and the frequency bandwidth that can be improved can be controlled to be wider, and The amount of noise reduction can also be increased.
[0053]
Even if such a vibrating body is laminated with a sound absorbing material, the vibration of the vibrating body and the sound absorbing effect of the sound absorbing material can be exhibited even if the vibration is not hindered and the surface density of the plate-shaped sound insulating body is not large. Thereby, the amount of improvement in noise in the high frequency range can be greatly increased.
[0054]
Thus, the soundproofing material provided with the sound absorbing material can further improve the transmission loss in the low frequency range and the high frequency range. As a sound absorbing material layer to be provided, a thin layer of about 2 mm is also effective, and if it is about 20 mm, it is also effective in the 500 Hz band of the middle frequency range, and the effective area on the low frequency side shifts to a wider frequency. Since this phenomenon changes little by little depending on the surface density of the plate-like sound insulating material, the interval between the vibrators, and the weight of the vibrators, it is preferable to fine-tune it in advance by a test or the like.
[0055]
The sound-absorbing material suitably used in the present invention is, specifically, a fiber-based sound-absorbing material such as glass wool, rock wool, felt, non-woven fabric, urethane, various rubbers, crushed products of polymers such as polyethylene and polypropylene, and fibers. It is possible to use a sound absorbing material of a porous material family obtained by solidifying and shaping refuse, a crushed product of rubber or polymer foam with various binders, and a sound absorbing material of a metal foam molded product such as aluminum.
[0056]
Further, in the present invention, a film molded body can be provided on one or both surfaces of the plate-shaped sound insulating body and each of the vibrators. This film molded body is provided with a plurality of spaced apart projections, and each projection has an air chamber inside. This film molded body is formed by laminating a flat film and an uneven film having been subjected to uneven processing.
[0057]
FIGS. 10 and 11 show the soundproofing material of this example. In the soundproofing material 37, a film formed body 40 is provided on the surface of the plate-shaped soundproofing body 39 opposite to the vibration body 38. In the film molded body 40, the flat film 40a and the uneven film 40b are bonded to each other to form a convex portion 41. Between both the flat film 40a and the uneven film 40b, air is formed inside the convex portion 41. A chamber 40c is formed.
[0058]
In this way, by laminating such a film molded body on at least one surface of the plate-shaped sound insulating body on which countless vibrators are fixed, it is possible to widen a low frequency range in which noise can be improved.
[0059]
Further, a cushioning material 42 can be provided between the convex portions of the film molded body as in a soundproofing material 37 'shown in FIG. As such a cushioning material, one or both of a crosslinked viscoelastic body and a foamed crosslinked viscoelastic body can be used. By interposing such a cushioning material between the protrusions of the film molded body, it is possible to further improve the soundproofing performance in a 250 to 500 Hz middle frequency range, which is difficult to overcome with a vibrating plate-like sound insulator or sound absorbing material. it can.
[0060]
As described above, according to the soundproofing material of the present invention, the frequency at which soundproofing can be performed can be adjusted over a wide range from a low frequency to a high frequency by adjusting the material and arrangement of the vibrating body and the plate-like soundproofing body.
[0061]
In particular, in the present invention, by changing the surface density and tension of the plate-shaped sound insulating body, it is possible to adjust the frequency at low and high frequencies and adjust the sound insulation volume. Further, in the present invention, by adjusting the mass and the arrangement interval of the vibrating body, it is possible to adjust the frequency and the sound insulation volume which can be improved.
[0062]
Further, in the present invention, by using a soundproofing material in which a sound absorbing material is combined, the sound insulation can be increased, and further, by increasing the thickness of the sound absorbing layer, the frequency that can be improved can be adjusted to the middle frequency range. it can.
[0063]
Further, in the present invention, the soundproofing material is formed by combining a sheet having an air chamber and a sheet provided with a viscoelastic body around the air chamber, so that a drop in performance in a middle frequency range can be prevented.
[0064]
INDUSTRIAL APPLICABILITY The soundproofing material of the present invention can be applied to soundproofing applications in many fields where noise prevention is required for walls, ceilings, pipe spaces of buildings, outer peripheries of air conditioning ducts and plumbing pipes, vehicles, ships, aircraft, and the like. it can. In particular, according to the present invention, it is possible to provide a light-weight, space-saving, and low-cost soundproof material when taking measures against noise in a desired frequency band.
[0065]
【Example】
Hereinafter, the present invention will be described more specifically based on examples and comparative examples with reference to the drawings. FIG. 12 is a plan view of a reverberation room for measuring the transmission loss of the soundproofing material. FIG. 13A is a partial longitudinal sectional view of a soundproofing material according to a reference example of the present invention. FIG. 13B is a plan view of the soundproofing material of FIG. FIG. 14A is a partial longitudinal sectional view of a soundproof material according to another reference example of the present invention. FIG. 14B is a plan view of the soundproofing material of FIG. FIG. 15 is a partial vertical cross-sectional view of a soundproof plate of an example of a comparative example.
[0066]
Reference Example 1
The soundproofing material shown in FIGS. 1A and 1B was manufactured. A non-vulcanized butyl rubber sheet (2 mm thick) was used as the plate-like sound insulator, and a 5 mm thick butyl rubber sheet having a specific gravity of 1.75 cut into a 30 mm square was used as the vibrator. The mass of one vibrator was 7.9 g.
[0067]
Next, as shown in FIG. 1 (b), ruled lines were vertically and horizontally formed on the non-vulcanized butyl rubber sheet at intervals of 30 mm. The vibrators were arranged at four corners and five places in the center within a range of 150 mm square. At this time, the vibrating body was attached with a butyl adhesive so that the distance between the centers of gravity of the vibrating bodies was 120 mm.
[0068]
The soundproofing material thus obtained was used as a sample, and the soundproofing performance was tested in a reverberation room 43 shown in FIG. The reverberation room 43 is divided into two rooms 43a and 43b, each of which is provided with

soundproof doors

44a and 44b,

speakers

45a and 45b, and

microphones

46a and 46b. A gypsum board 47 having a thickness of 9.5 mm is provided between the two rooms 43a and 43b.
[0069]
In the test, the surface of the test piece on the side of the plate-like sound insulator was mounted on the gypsum board 47, and the transmission loss was measured at a frequency of 50 Hz to 5000 Hz. For the measurement, a method of measuring sound transmission loss in a laboratory according to JIS-A-1416-1974 was used. However, in JIS-A-1417, in principle, the test is performed at 1/3 octave center frequency of 16 frequencies from 125 Hz to 4000 Hz, but this test is also aimed at improving low frequency and high frequency noise. Therefore, 50 to 100 Hz and 5000 Hz at the center frequency of the 1/3 octave were also included in the measurement range. The results are shown in Table 1.
[0070]
Reference Example 2
The soundproofing material 48 shown in FIGS. 13A and 13B was manufactured. As the vibrating body 49, a 6 mm thick butyl rubber sheet having a specific gravity of 1.75 was cut into 10 mm square and used. As the plate-like sound insulator 50, a non-vulcanized butyl rubber sheet (2 mm thick) was used. The mass of one vibrator was 1.1 g.
[0071]
Next, as shown in FIG. 13 (b), ruled lines are vertically and horizontally formed at an interval of 15 mm on the plate-shaped sound insulating body 50, and the vibrating body 49 is arranged on the intersection of the ruled lines so that the distance between the centers of gravity is 15 mm. The soundproofing material 48 was manufactured by bonding with a butyl adhesive. This soundproofing material was used as a test piece, mounted on a gypsum board in the same manner as in Reference Example 1, and the transmission loss was measured. The results are shown in Table 1.
[0072]
Reference Example 3
The soundproofing material 51 shown in FIGS. 14A and 14B was manufactured. As the vibrator 52, a 8.5 mm thick porcelain tile (94 mm square) having a mass of 157 g was used. As the plate-like sound insulator 53, a non-vulcanized butyl rubber sheet 2 mm thick was used. The vibration member 52 was attached by urethane caulking so that the distance between the centers of gravity was 300 mm, and the soundproof material 51 was manufactured. This soundproofing material was used as a test piece, mounted on a gypsum board in the same manner as in Reference Example 1, and the transmission loss was measured. The results are shown in Table 1.
[0073]
Reference example 4
The soundproofing material shown in FIGS. 4A and 4B was manufactured. As the plate-like sound insulator 13, an EVA sheet having a thickness of 1 mm was used. As the vibrator 12, a 20 mm polyethylene foam sheet 12b having a thickness of 2 mm and a porcelain tile 12a (25 mm square) having a thickness of 5 mm were used. Acrylic adhesive is applied to both sides of the polyethylene 20-fold foam sheet 12b, a porcelain tile 12a is stuck on the upper surface of the sheet 12b, and release paper is stuck to the lower surface of the polyethylene 20-fold foam sheet 12b, and the tiles 12a are cut one by one. And the vibrating body 12. The mass of one vibrator is 6.6 g.
[0074]
As shown in FIG. 4 (b), a 20-fold polyethylene foam sheet surface was attached to the EVA sheet such that the distance between the centers of gravity of the vibrators was 100 mm on an EVA sheet having a thickness of 1 mm, thereby producing a soundproofing material. . This soundproofing material was used as a test piece and attached to a gypsum boat in the same manner as in Reference Example 1, and the transmission loss was measured. The results are shown in Table 1.
[0075]
Reference example 5
The soundproofing material 4 shown in FIGS. 2A and 2B was manufactured. The vibrating body 5 and the plate-shaped sound insulating body 6 were produced as a press vulcanized rubber sheet having convex portions on both sides. The thickness of the rubber sheet portion was 2 mm, and the upper and lower convex portions were located above and below the same portion as shown in FIG. The protrusion has a cylindrical shape with a diameter of 10 mm and a height of 10 mm, and functions as a vibrator. The same natural rubber SBR blend rubber was used for both the sheet portion and the vibrating body portion, and the specific gravity was 2.20. As shown in FIG. 2B, the arrangement of the vibrating members was set such that the distance between the centers of gravity of the vibrating members was 40 mm. The upper and lower vibrators were regarded as one, and the vibrating body was 3.5 g / piece. This soundproofing material was attached to a gypsum board in the same manner as in Reference Example 1, and the transmission loss was measured. The results are shown in Table 1.
[0076]
Reference Example 6
The soundproofing material of FIGS. 5A and 5B was manufactured. The vibrating body and the plate-shaped sound insulating body were produced by laminating two press vulcanized rubber sheets each having a convex portion on one side. The thickness of one rubber sheet portion is 1 mm, and the convex portion has a cylindrical shape with a diameter of 10 mm and a height of 10 mm, and functions as a vibrator. Both the sheet portion and the vibrating portion were made of the same natural rubber / SBR blend rubber, and the specific gravity was 2.20. The vibrator was provided with a center of gravity interval of 40 mm. The mass of the vibrator was 1.8 g / piece.
[0077]
The two sheets are bonded together with the vibrating body on one side and the vibrating body on the remaining side so that the distance between the centers of gravity of the vibrating bodies is 20 mm, and the two sides of the vibrating body as shown in FIG. There was manufactured a soundproofing material which had a convex portion and did not overlap the convex portions on the upper and lower surfaces. This soundproofing material was used as a specimen, and attached to a gypsum board in the same manner as in Reference Example 1 to measure the transmission loss. The results are shown in Table 1.
[0078]
Reference Example 7
A 10 mm-thick nonwoven fabric was provided on the surface of the soundproofing material used in Reference Example 1 opposite to the vibrating body, and the soundproofing material shown in FIGS. 7A and 7B was manufactured. The nonwoven fabric side of this soundproof material was attached to a gypsum board, and the transmission loss was measured in the same manner as in Reference Example 1. The results are shown in Table 1.
[0079]
Reference Example 8
A non-woven fabric having a thickness of 2 mm was provided on the surface opposite to the vibrating body of the soundproofing material used in Reference Example 1, and the soundproofing material shown in FIGS. 8A and 8B was manufactured. The nonwoven fabric side of this soundproof material was attached to a gypsum board, and the transmission loss was measured as in Reference Example 1. The results are shown in Table 1.
[0080]
Reference Example 9
On the opposite side of the vibrating body of the soundproofing material used in Reference Example 1, a 4-mm-thick uneven sheet provided with an infinite number of air chambers formed of two films, a flat film and a film subjected to uneven processing, was provided as shown in FIG. The soundproofing material shown was manufactured. The uneven film side of this soundproof material was attached to a gypsum board, and the transmission loss was measured in the same manner as in Reference Example 1. The results are shown in Table 1.
[0081]
[Table 1]

[0082]
Reference example 10
A room temperature curing reaction type elastic body was provided in the concave portion of the uneven sheet of the soundproofing material used in Reference Example 9 to produce the soundproofing material shown in FIG. 11. Using this soundproofing material as a test sample, the transmission loss was measured in the same manner as in Reference Example 1. The results are shown in Table 2.
[0083]
Example 1
The soundproofing material shown in FIG. 6 was manufactured. The periphery of the sound-insulating material plate-shaped sound insulator used in Reference Example 1 was sandwiched between a frame material 23 made of plywood having a thickness of 12 mm and a width of 20 mm and a plywood 24 having a thickness of 3 mm and a width of 20 mm. Stopping, tension was given to the plate sound insulator, and tension was given. This soundproofing material was attached to a gypsum board, and the transmission loss was measured in the same manner as in Reference Example 1. The results are shown in Table 2.
[0084]
Reference Example 11
A soundproofing material as shown in FIGS. 3A and 3B was manufactured. However, in the soundproofing material of this example, the specific gravity gradient was formed so that the high specific gravity component was unevenly distributed on the vibrating body side, and the high specific gravity component was not localized on the plate-shaped sound insulating body side.
[0085]
Flexible obtained by mixing high specific critical particle size filler such as iron powder, tungsten powder, silica sand, medium specific gravity small particle size filler such as talc and mica, and low specific critical particle size filler such as glass balloon The epoxy was poured into a mold to produce a soundproofing material as shown in FIG. As shown in FIG. 3B, this soundproofing material has a specific gravity gradient such that the upper surface side of the convex portion serving as a vibrator has a high specific gravity. The vibrating body of this soundproofing material has a mass of 2.3 g and the distance between the centers of gravity of the vibrating bodies is 10 mm. This soundproofing material was attached to a gypsum board, and the transmission loss was measured as in Reference Example 1. The results are shown in Table 2.
[0086]
Reference Example 12
The soundproofing material shown in FIG. 9 was manufactured. A 10 mm square net was used as the plate-like sound insulator, and a 25 mm-thick porcelain tile (one piece, 6.6 g in mass) was attached thereto as a vibrator using a hot melt adhesive. The distance between the centers of gravity of the vibrators was 30 mm. This is applied to a 15 mm thick basis weight of 1.6 kg / m.²Of non-woven fabric with a basis weight of 700 g / m with a thickness of 20 mm²And a soundproofing material was produced. This soundproofing material was attached to a gypsum board, and the transmission loss was measured as in Reference Example 1. The results are shown in Table 2.
[0087]
Comparative Example 1
The transmission loss of a 9.5 mm thick gypsum board was measured in the same manner as in Reference Example 1. The results are shown in Table 2.
[0088]
Comparative Example 2
A non-vulcanized butyl rubber sheet having a thickness of 2 mm was attached to the gypsum board of Comparative Example 1, and the transmission loss was measured as in Reference Example 1. The results are shown in Table 2.
[0089]
Comparative Example 3
As shown in FIG. 15, a 10 mm-thick nonwoven fabric 55 was attached to a 2 mm-thick non-vulcanized butyl rubber sheet 54 to produce a soundproof plate 56. The nonwoven fabric 55 side of the soundproof plate 56 was attached to a gypsum board, and the transmission loss was measured as in Reference Example 1. The results are shown in Table 2.
[0090]
[Table 2]

[0091]
Examples and comparative examples will be described based on the measured values shown in Tables 1 and 2.
In Reference Example 1, the plate-shaped sound insulator was a non-vulcanized butyl rubber sheet having a thickness of 2 mm, the vibrator was 5 mm thick, 300 mm square, the mass was 7.9 g / piece, the center of gravity of the vibrator was 120 mm, and gypsum was used. This is an example of mounting on a board. Compared to Comparative Example 2 in which a non-vulcanized butyl rubber sheet was attached to a gypsum board 9.5 mm in thickness, it was improved over the entire frequency range, but was especially improved in the 50-80 Hz hard-to-improve band. In Comparative Example 2, although the drop of the 4 kHz coincidence of Comparative Example 1 (gypsum board) is significantly improved, a slight drop is seen, but in Reference Example 1, no drop is seen and the amount of improvement is large.
[0092]
Reference Example 2 is an example in which the plate-shaped sound insulating body of Reference Example 1 is used to reduce the weight of the vibrator to 1.1 g / piece and to reduce the distance between the centers of gravity of the vibrators to 15 mm. Although the amount of improvement in the band of 50 to 80 Hz is small, a significant improvement is seen in the band of 2 kHz or more as compared with Comparative Example 2. Although it is lighter than Reference Example 1, the improvement amount is large at 2 kHz or more.
[0093]
Reference Example 3 is an example in which the plate-shaped sound insulating body of Reference Example 1 is used, and the vibrator is as heavy as 157 g / piece and the distance between the centers of gravity of the vibrators is as wide as 300 mm. A very large improvement is shown in the band of 50 to 100 Hz. Conversely, at 200 to 630 Hz, there is a portion worse than that of Comparative Example 2. The frequency of 3.15 kHz or more is almost equivalent to that of the reference example 1.
[0094]
In Reference Example 4, an EVA sheet having a low areal density of 1 mm thick was used for the plate-shaped sound insulating body, and 6.6 g / vibration body was placed between the centers of gravity via a 2 mm thick polyethylene foam sheet between the vibrating body and the EVA sheet. In this example, the distance is set to 100 mm. At 50 to 63 Hz, a soundproof effect is clearly seen. Although the areal density is lower than that of the non-vulcanized butyl rubber sheet having a thickness of 2 mm, the performance at 125 Hz to 1.25 kHz is almost the same as that of Comparative Example 2. At 1.6 kHz to 5 kHz, the gypsum board of Comparative Example 1 shows a significant improvement, though slightly inferior to Comparative Example 2. This indicates that it is effective in achieving improvement effects while being lightweight.
[0095]
In Reference Example 5, the plate-shaped sound insulator and the vibrator are made of the same material having a specific gravity of 2.2, and the vibrators are located at the same position on both sides of the plate-shaped sound insulator having a thickness of 2 mm. In this example, the distance between the centers of gravity of the vibrating bodies was set to 40 mm at 5 g / piece. The amount of improvement at 50 to 80 Hz is large, and the improvement effect is particularly large at 1.6 kHz or more as compared with Comparative Example 2.
[0096]
In Reference Example 6, a sheet-shaped sound insulator having a thickness of 1 mm and a vibrator were formed as a single material having a specific gravity of 2.2 as a plate-shaped sound insulator, and two sheets provided with a vibrator on one surface were used. This is an example in which a 2 mm-thick plate-shaped sound insulator is stuck together so as not to come to the same position, and the mass of the vibrator is 1.8 g / piece and the distance between the centers of gravity of the vibrators is 40 mm. The effect is great at low frequencies of 50 to 250 Hz, and the improvement over 1 kHz is very high.
[0097]
Reference Example 7 is an example in which a nonwoven fabric thickness of 10 mm was attached to the opposite surface of the vibrator of Reference Example 1. Compared with Comparative Example 3 in which the non-vulcanized butyl rubber has a thickness of 2 mm and a thickness of the nonwoven fabric of 10 mm, the improvement at 50 to 125 Hz is large. At 200 to 500 Hz, it is worse than Comparative Example 3, and at 200 to 400 Hz, it is worse than Comparative Example 2, but the improvement effect in the band of 800 Hz or more is remarkable.
[0098]
Reference Example 8 is an example in which the nonwoven fabric of Reference Example 7 was changed to a thickness of 2 mm. In the range of 50 to 125 Hz, the improvement is larger than that of Comparative Example 3. At 200 to 1 kHz, there is a part worse than the comparative example, but at 1.6 kHz or more, there is a very large improvement effect.
[0099]
Reference Example 9 is a case where the nonwoven fabrics of Reference Examples 7 and 8 are changed to an uneven sheet thickness of 4 mm having countless air chambers. An improvement of 50 to 63 Hz has been achieved, and there is no particular tendency that an improvement of 100 to 315 Hz can be achieved. From 500 Hz to 800 Hz, although it is worse than Comparative Example 3, it can be greatly improved in all other bands.
[0100]
Reference Example 10 is an example in which a crosslinked viscoelastic body is formed around the convex air chamber of the uneven sheet of Reference Example 9. The improvement of Comparative Example 3 was improved in all frequency bands, and the improvement effect was particularly large at 80 to 400 Hz, and the improvement at 20 kHz or more was also large.
[0101]
The first embodiment is an example in which a frame material for reinforcing tension is provided around the plate-shaped sound insulating body of the first embodiment. At 50 to 80 Hz, the amount of improvement is very large. On the other hand, at 200 to 630 Hz, it is worse than that of Comparative Example 2, but at 800 Hz or more, a very large improvement is shown.
[0102]
Reference Example 11 is a flexible epoxy sheet provided with a vibrating body and a sheet having a specific gravity gradient obtained by mixing and curing a filler having a specific gravity of high, medium, or low. The vibrating body has a mass of 2.3 g / piece. In this example, the distance between the centers of gravity of the vibrating bodies is 10 mm. At 50 to 160 Hz, the amount of improvement is large compared to Comparative Example 2. The amount of improvement at 800 Hz or higher is large, and there is no drop at 4 kHz. In this example, it is advantageous that there is no significant drop at all frequencies.
[0103]
Reference Example 12 uses a mesh as a plate-like sound insulator and a porcelain tile as a vibrator, and has a thickness of 15 mm and 1.6 kg / m.²0.7kg / m at 20mm thickness²This is an example of a non-woven fabric with a weight per unit area. The mass of the vibrating body was 6.6 g / piece, and the distance between the centers of gravity of the vibrating bodies was 30 mm. At 50 Hz and 63 Hz, a significant improvement is observed. At 2 kHz or more, performance degradation due to the coincidence effect peculiar to the gypsum board is seen.
[0104]
Comparative Example 1 is a gypsum board alone, and shows a drop on the low frequency side and a drop due to a coincidence effect of 2 kHz or more.
[0105]
Comparative Example 2 is an example in which a non-vulcanized butyl rubber sheet having a thickness of 2 mm was attached to Comparative Example 1. This was used for comparison with the vibrating body-equipped sheet of this example.
[0106]
Comparative Example 3 is an example in which a 10 mm thick nonwoven fabric was attached between the non-vulcanized butyl rubber sheet of Comparative Example 2 and the gypsum board. It was used for comparison with an example in which the nonwoven fabric and the concavo-convex sheet of this example were placed between a plate-shaped sound insulator with a vibrator and a gypsum board.
[0107]
As described above, the soundproofing material in which the vibrating body is provided on the plate-like sound insulating body has a difference in the amount of improvement, however, as compared with Comparative Examples 2 and 3 without the vibrating body, the soundproofing material has a 50 Hz to 80 Hz band. High effect. Particularly, a large effect can be obtained by using a heavy vibrating body of Reference Example 3, an example in which the tension of the plate-shaped sound insulating body of Example 1 is maintained, and a net attached with the vibrating body of Reference Example 12 by a nonwoven fabric. This is an example.
[0108]
As examples having a large noise improvement effect in the 100 to 150 Hz band, an example using an uneven sheet having an air chamber in Reference Example 9 and a crosslinked viscoelastic body provided in a concave portion around a convex air chamber in Reference Example 10 are provided. Examples can be given.
[0109]
In the soundproofing material using the nonwoven fabrics of Reference Examples 7 and 8, the low-frequency improvement band tends to be as wide as 50 to 125 Hz. Further, by reducing the thickness, the effective frequency of the improvement effect on the high frequency side shifts to a lower frequency, and the improvement effect becomes extremely large. As can be seen from Reference Examples 5 and 6, when the vibrating body is provided on both sides, the amount of improvement is increased by about 2 dB at 50 to 63 Hz by shifting the vibrating body position to one side, and the amount of improvement is 1 to 4 dB at 1250 Hz or more. Can increase. In each embodiment, the improvement effect on the high frequency side is very high.
[0110]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the soundproofing material of this invention, the low frequency noise of the sounding body as a soundproofing object is remarkably improved by vibrating the countless vibrating bodies provided in the shape of dots on the plate-shaped sound insulating body of a predetermined material. can do.
[0111]
Further, according to the soundproofing material of the present invention, the frequency that can be soundproofed can be adjusted over a wide range from a low frequency to a high frequency by adjusting the material and arrangement of the vibrating body and the plate-shaped sound insulating body.
[Brief description of the drawings]
FIG. 1A is a partial longitudinal sectional view of a soundproofing material according to a reference example of the present invention. (B) is a top view of the soundproofing material of (a).
FIG. 2A is a partial longitudinal sectional view of a soundproof material according to another reference example of the present invention. (B) is a top view of the soundproofing material of (a).
FIG. 3A is a partial longitudinal sectional view of a soundproofing material of still another reference example of the present invention. (B) is a partial enlarged longitudinal sectional view of the soundproofing material of (a).
FIG. 4 (a) is a partial longitudinal sectional view of a soundproofing material of still another reference example of the present invention. (B) is a top view of the soundproofing material of (a).
FIG. 5 (a) is a partial longitudinal sectional view of a soundproofing material of still another reference example of the present invention. (B) is a top view of the soundproofing material of (a).
FIG. 6 is a longitudinal sectional view of a soundproofing material according to an example of the present invention.
FIG. 7A is a partial longitudinal sectional view of a soundproofing material according to still another reference example of the present invention. (B) is a top view of the soundproofing material of (a).
FIG. 8A is a partial longitudinal sectional view of a soundproofing material according to still another reference example of the present invention. (B) is a top view of the soundproofing material of (a).
FIG. 9 is a longitudinal sectional view of a soundproof material according to still another reference example of the present invention.
FIG. 10 is a partial longitudinal sectional view of a soundproofing material of still another reference example of the present invention.
FIG. 11 is a longitudinal sectional view of a soundproof material according to still another reference example of the present invention.
FIG. 12 is a plan view of a reverberation room for measuring transmission loss of the soundproofing material.
FIG. 13A is a partial longitudinal sectional view of a soundproofing material according to still another reference example of the present invention. (B) is a top view of the soundproofing material of (a).
FIG. 14 (a) is a partial longitudinal sectional view of a soundproofing material of still another reference example of the present invention. (B) is a top view of the soundproofing material of (a).
FIG. 15 is a partial longitudinal sectional view of a soundproof plate as an example of a comparative example.

Claims

A soundproofing material attached to the outside of the sounding body and reducing noise of the sounding body,
The soundproofing material includes a plurality of vibrators and a plate-shaped sound insulator that supports each of the vibrators, and the plate-shaped sound insulator is a sheet, a film, or a nonwoven fabric using, alone or in combination with various rubbers, polymers, and rubber asphalts. , Felts alone or in combination, wherein each of the vibrators is fixed on at least one surface of the plate-like sound insulator, and each of the vibrators is separated from each other at a predetermined interval, The peripheral part of the body is bent and pulled by a frame material, the frame material holds the tension of the plate-shaped sound insulator, and each of the vibrators vibrates due to radiation sound of the sounding body. And soundproofing material.

At least one of each of the vibrators and the plate-shaped sound insulator is made of two or more components having different specific gravities, and when the soundproofing material is viewed in a cross section perpendicular to the plane of the plate-shaped body, The component having a high specific gravity is localized on the surface side, or a specific gravity gradient is formed, and a reinforcing material is put in a cross-shaped portion in a portion surrounded by the frame material, and the plate-shaped The soundproofing material according to claim 1, wherein an area of the soundproofing body to which tension is applied is also divided, and each of the vibrating bodies vibrates by radiation sound of the sounding body.

The vibrating body is composed of two or more layers of different types, and has a deformation such as a foam or nonwoven fabric as a lower layer of the vibrating body or a film having a plurality of spaced apart convex portions and each convex portion having an air chamber therein. The soundproofing material according to claim 1, wherein an easy-to-wear material is fixed to the plate-shaped sound insulating body.