JP3555035B2

JP3555035B2 - Dynamic vibration absorber

Info

Publication number: JP3555035B2
Application number: JP20738691A
Authority: JP
Inventors: 郁夫下田
Original assignee: Oiles Corp
Current assignee: Oiles Corp
Priority date: 1991-07-24
Filing date: 1991-07-24
Publication date: 2004-08-18
Anticipated expiration: 2019-08-18
Also published as: JPH0526294A

Description

【０００１】
【産業上の利用分野】
本発明は、ビル、集合住宅及び一般の住宅の床、橋梁並びに機械本体及びその基礎等の構造物の何等かの原因による強制的な振動を可及的速やかに減衰せしめる制振装置、いわゆる動吸振装置（ダイナミックダンパ）に関する。
【０００２】
【従来の技術】
この種動吸振装置は、一般に、コイルばね部材と、このコイルばね部材に連結された重錘と、この重錘の振動エネルギを吸収するエネルギ吸収装置と、振動減衰作動中における重錘の意図しない揺動を防止して重錘の本来の振動を案内する摺動案内部材とを具備している。
【０００３】
【発明が解決しようとする課題】
ところでこの従来の動吸振装置は、上述の通り、重錘に対する摺動案内部材を具備するため、この摺動案内部材の重錘に対する案内面が十分に平滑でないと、重錘の振動が摺動案内部材を介して、摺動案内部材を支持する構造物に伝達される。この構造物は、多くの場合一般に、現に振動を減衰させようとする対象物であり、従って上述の場合この構造物に二次的振動を生じさせる場合がある。また摺動案内部材を具備している場合、加速度の小さい振動は重錘と摺動案内部材との間の摩擦抵抗力に打ち勝つことができず、その結果このような振動では重錘の振動エネルギがエネルギ吸収装置で吸収されることなしにそのまま摺動案内部材に伝達され、構造物に生じた加速度の小さい振動は結局効果的に減衰されないこととなる。また従来の動吸振装置では、上述の通り摺動案内部材を設けてなるため、広い設置場所を必要とし一般の住宅の床などには適用し難い。
【０００４】
加えて、振動においては多くの場合、それに伴って騒音が発生するが、従来の動吸振装置では、これを効果的になくすことが困難である。
【０００５】
本発明は前記諸点に鑑みてなされたものであり、その目的とするところは、摺動案内部材を用いることなしに効果的に構造物の振動を減衰させることができ、加えて設置場所をそれ程必要としない上に、振動に伴う騒音をも低減し得る動吸振装置を提供することにある。
【０００６】
【課題を解決するための手段】
本発明によれば前記目的は、一組が、対向配置された少なくとも一対の板状弾性部材及びこの板状弾性部材の曲げにより板状弾性部材の板面に沿う剪断応力が内部に生じるように板状弾性部材の夫々に加硫接着により固く接合されて板状弾性部材の間に配置された粘弾性部材を具備してなる組合せ体の複数の組と、各組の一対の板状弾性部材の外周端を自由端として各組の一対の板状弾性部材を互いに間隔をもって支持するように、一端が各組の板状弾性部材のほぼ中央部に固着されており、他端が振動源に取付けられるようになっている取付部材とを具備しており、一の組の板状弾性部材と他の一の組の板状弾性部材とは、互いに異なる固有振動周期の振動を減衰するようになっている動吸振装置によって達成される。
【０００７】
本発明の一つの好ましい例では、板状弾性部材には重錘が取付けられる。この重錘を取付けることにより本動吸振装置によって吸振し得る振動の周期を好ましく調整し得る。このような調整は、一対の板状弾性部材を挟みつける板部材によっても行い得る。
【０００８】
本発明の他の好ましい例では、板状弾性部材は円盤状に形成されており、取付部材の一端は、板状弾性部材のほぼ中心部に固着されている。
【０００９】
本発明における粘弾性部材としては、ウレタン系高分子材料、オレフィン系高分子材料、シリコン系高分子材料及びアスファルト等を混入せしめた高減衰ゴム等を例示し得るが、その他の部材でもよいのはもちろんである。ゴムを用いた粘弾性部材の場合は、板状弾性部材の曲げにより板状弾性部材の板面に沿う剪断応力が内部に生じるように板状弾性部材にこれを加硫接着により接合されるのが好ましい。一対の板状弾性部材と粘弾性部材との組合せ体を、いわゆる制振鋼板で具体化してもよいのはもちろんである。
【００１０】
本発明では、構造物に取り付けられる取付部材に一対の板状弾性部材と粘弾性部材との組合せ体を複数組設け、構造物が有する複数の固有振動周期の夫々を夫々が担当して減衰させるように一対の板状弾性部材と粘弾性部材との組合せ体の各組を形成する。ところで上記の組合せ体の例は、一対の板状弾性部材と粘弾性部材とからなる三層構造であるが、例えば板状弾性部材と粘弾性部材とを交互に配置して三層以上、即ち多層の板状弾性部材と粘弾性部材との組合せ体でもよいのはもちろんである。換言すれば、本発明では、少なくとも、対向配置された一対の板状弾性部材と、この板状弾性部材の間に配置された粘弾性部材とを各組の組合せ体が具備していればよいのである。
【００１１】
本発明では上述の通り、板状弾性部材は円盤状に形成されていることが好ましいのであるが、しかしこれに特に限定されず、正方形、長方形、楕円形等種々の形状であってもよい。そして粘弾性部材は、板状弾性部材の間の全体に亘って配置されている必要はなく、分散して配置されていてもよいのである。また吸振する振動周期を調整するために設けられる重錘も必ずしも板状弾性部材の周縁部に、また周縁部の全てに亘って配置する必要はなく、分散して、場合により周縁部以外の部分に配置して設けてもよいのである。
【００１２】
尚、本発明の動吸振装置に更に効果的な吸音効果をもたせる場合には、床等に対面する板状弾性部材の表面にフェルト等の吸音材をはりつけてもよく、或いは板状弾性部材のその表面を凹凸のある吸音面としてもよい。
【００１３】
【作用】
本発明の動吸振装置は取付部材を介して構造物、例えば住宅の床に取付けられる。しかして住宅の床が例えば人の歩行で振動させられると、取付部材を介してこの振動が対向配置された一対の板状弾性部材と粘弾性部材との組合せ体に伝達され、取付部材の一端を支点として一対の板状弾性部材の自由端側が床の固有振動数に対して位相をほぼ９０°ずらせて振動する。この振動に起因する板状弾性部材の曲げにより粘弾性部材の内部に剪断応力が板状弾性部材の板面に沿って生じ、この粘弾性部材の粘性剪断応力の発生により振動エネルギが可及的速やかに減衰される。また、この粘弾性部材の粘性剪断応力により、床の振動がおさまった後は、板状弾性部材の振動は速やかに減衰される。
【００１４】
以下本発明を、図面に示す好ましい具体例に基づいて説明する。これにより前記発明及び更に他の発明が明瞭となるであろう。尚、本発明はこれら具体例に何等限定されないのである。
【００１５】
【具体例】
図１において、本発明の動吸振装置１は、一例として、相互に対向配置された一対の板状弾性部材２及び３と、板状弾性部材２及び３の間に配置された粘弾性部材４と、板状弾性部材２及び３の外周端５を自由端として一対の板状弾性部材２及び３を支持するように、一端６がナット７を介して板状弾性部材２及び３に固着されており、他端８が構造体としての例えば住宅の床９の下面１０に取付けられた取付部材１１とを基本的に具備している。
【００１６】
板状弾性部材２及び３並びに粘弾性部材４は、本例では、円盤状に形成されており、取付部材１１の一端６は、円盤状の板状弾性部材２及び３の中心部（支点）に固着されている。板状弾性部材２及び３の夫々の厚みｔ、支点から自由端までの距離すなわち半径ｒ、ならびに質量は、吸振しようとする振動の周期、即ち本動吸振装置１を適用する床９の固有振動周期に対して位相が９０°ずれるように設定され、一つの例として厚さ３ｍｍ、半径２５０ｍｍ、質量４．６ｋｇを例示し得る。
【００１７】
本例の粘弾性部材４は薄いゴム部材からなり、加硫接着によりその両表面１２及び１３は夫々板状弾性部材２及び３に固く接合されている。このように強く固く粘弾性部材４が板状弾性部材２及び３に接合されている結果、板状弾性部材２及び３の曲げにより粘性剪断応力が板状弾性部材の板面に沿って、即ちＡ方向に沿って粘弾性部材４の内部に生じるようになっている。
【００１８】
取付部材１１は本例では縮径部１４を有する棒状部、換言すれば円柱状部１５と、円柱状部１５に連結された基部１６と、円柱状部１５の先端に形成されたおねじ部１７とからなり、縮径部１４に板状弾性部材２及び３並びに粘弾性部材４の夫々の貫通孔１８、１９及び２０が配置されており、おねじ部１７にナット７が螺着されてこれにより板状弾性部材２及び３並びに粘弾性部材４は、しっかりと取付部材１１の一端６に固着されている。基部１６は、ねじ２１等を介して振動源としての床９に固定されており、こうして取付部材１１はその他端８で床９の振動面としての下面１０に取付けられている。尚、床９は一般に一つのみの固有振動周期を有するものではなく複数の振動モードを有し、従ってこのように形成されている本例の動吸振装置１はその吸振しようとする振動モードの腹が生じる床９の部位に配置される。
【００１９】
以下動作を説明すると、人の歩行などにより床９にＢ方向の振動が生じると、この振動は取付部材１１を介して板状弾性部材２及び３に伝達され、板状弾性部材２及び３は、図２に示すように取付部材１１の一端６を支点としてＣ方向に位相が９０°ずれて振動し、この振動で板状弾性部材２及び３に曲げが生じる。板状弾性部材２及び３のこの曲げにより粘弾性部材４の内部に粘性剪断応力が板状弾性部材２及び３の板面に沿って、即ちＡ方向に沿って生じ、粘弾性部材４の粘性剪断応力の発生により板状弾性部材２及び３の振動エネルギ、延いては床９の振動エネルギが可及的速やかに減衰され、その結果床９の振動は直ちになくなることとなる。
【００２０】
尚、本例のように円盤状の板状弾性部材２を用いる場合には、円盤状の板状弾性部材２が床９に生じた振動音に対する反射板として機能する結果、遮音効果をも期待し得ることとなる。加えて床９に生じる振動の結果発生する音と、板状弾性部材２及び３の振動の結果発生する音との位相が、動吸振装置１から離れた位置で逆相となるように床９と板状弾性部材２との距離Ｌを設定すると、換言すれば取付部材１１の長さを選択すると、動吸振装置１は消音機能をももつこととなり、上述の遮音効果と相乗して床９の振動音を効果的に少なくし得る。すなわち、板状弾性部材２の板面が床９の下面１０に対面すると共に、床９の下面１０から板状弾性部材２までの距離Ｌが床９の下面１０の振動で生じる振動音との関連で設定された値になるように、取付部材１１が形成されると、動吸振装置１は消音機能と遮音効果とをもつことになり床９の振動音を効果的に少なくし得る。
【００２１】
ところで上記例の動吸振装置１では、板状弾性部材２及び３並びに粘弾性部材４の厚さ、半径ｒ、質量等により吸振しようとする振動モードに合わせたが、図３及び図４に示すようにこれらに加えて円環状の重錘４１及び４２を板状弾性部材２及び３の外周端５に取付けて、これにより吸振しようとする振動モードで動作するように調節して動吸振装置５０を構成してもよい。
【００２２】
また図５及び図６に示すように、本発明では板状弾性部材２及び３並びに粘弾性部材４に扇形の空所６１、６２及び６３を有した動吸振装置６４でもよく、このような空所６１、６２及び６３を形成した動吸振装置６４では、振動有効質量が増し、好ましい場合がある。尚、板状弾性部材２及び３並びに粘弾性部材４の全てにこのような空所６１、６２及び６３を設けることなく、例えば板状弾性部材２及び３又は粘弾性部材４のいずれか一方のみにこのような空所を設けるようにしてもよい。
【００２３】
更に図７に示すように取付部材１１に挿着された一対の所望の径をもった剛性の板部材７１及び７２でもって固く板状弾性部材２及び３並びに粘弾性部材４を挟みつけて動吸振装置７３を形成してもよく、このように一対の板部材７１及び７２を用いることによって、支点から自由端までの距離を調整し、動吸振装置７３で吸振することができる振動の周期を調節することができる。
【００２４】
上記は、板状弾性部材２及び３並びに粘弾性部材４からなる組合せ体の一組を取付部材１１に装着した基本的な例であり、本発明の一例は、図８に示すように夫々径の異なる板状弾性部材２及び３並びに粘弾性部材４からなる組合せ体の三組をスペーサ８１及び８２により間隔をもって取付部材１１に装着して、動吸振装置８３を形成する。本例のようにすると、一つの動吸振装置８３で異なる複数の固有振動周期の振動を一挙に減衰せしめることができる。尚、動吸振装置８３では、板状弾性部材２及び３並びに粘弾性部材４の径を異ならせて異なる複数の固有振動周期の振動を減衰せしめるようにしたが、これに代えて板状弾性部材２及び３並びに粘弾性部材４からなる組合せ体の三組において、その厚み又はその質量を変えるか、前述の重錘４１及び４２又は板部材７１及び７２を設けて異なる複数の固有振動周期の振動を一つの動吸振装置で減衰せしめるようにしてもよいのである。
【００２５】
また図９に示すように板状弾性部材２及び３並びに粘弾性部材４の夫々に放射方向に伸びるスリット９１を複数形成して動吸振装置９２を形成してもよく、このようにすることにより、固有振動数の調整も可能である。
【００２６】
【発明の効果】
本発明によれば、取付部材の一端を支点とする一対の板状弾性部材の自由端側の振動に起因する板状弾性部材の曲げにより粘弾性部材の内部に板状弾性部材の板面に沿う剪断応力を生じさせ、この粘弾性部材の剪断応力の発生により振動エネルギを可及的速やかに減衰させるものであるため、摺動案内部材を用いることなしに効果的に振動を減衰させることができ、加えて設置場所をそれ程必要としない上に、振動に伴う騒音をも効果的に低減し得る。しかも、本発明によれば、少なくとも一対の板状弾性部材と粘弾性部材との組を複数組具備し、一の組の板状弾性部材と当該一の組の板状弾性部材と間隔をもって取付部材に支持された他の一の組の板状弾性部材とが、互いに異なる固有振動周期の振動を減衰するようになっているために、一つの動吸振装置で異なる複数の固有振動周期の振動エネルギを一挙に可及的速やかに減衰せしめることができ、粘弾性部材が板状弾性部材の夫々に加硫接着により固く接合されているために、板状弾性部材の板面に沿う剪断応力を粘弾性部材の内部に確実に生じさせることができ、上記の効果と相俟って振動エネルギを可及的速やかに減衰せしめることができる。
【図面の簡単な説明】
【図１】本発明の好ましい一具体例の側面図である。
【図２】図１に示す具体例の動作説明図である。
【図３】本発明の好ましい他の具体例の側面図である。
【図４】図３に示す具体例の底面図である。
【図５】本発明の好ましい更に他の具体例の底面図である。
【図６】図５に示す具体例のＶＩ−ＶＩ線断面図である。
【図７】本発明の好ましい第４の具体例の側面図である。
【図８】本発明の好ましい第５の具体例の側面図である。
【図９】本発明の好ましい第６の具体例の底面図である。
【符号の説明】
１動吸振装置
２板状弾性部材
３板状弾性部材
４粘弾性部材
９床
１１取付部材[0001]
[Industrial applications]
The present invention relates to a so-called dynamic damping device for damping forced vibration caused by any cause such as a floor of a building, an apartment house and a general house, a bridge, and a structure such as a machine body and its foundation as quickly as possible. The present invention relates to a vibration absorbing device (dynamic damper).
[0002]
[Prior art]
This kind of dynamic vibration absorber generally includes a coil spring member, a weight connected to the coil spring member, an energy absorbing device that absorbs vibration energy of the weight, and an unintended weight of the weight during the vibration damping operation. A sliding guide member for preventing swinging and guiding the original vibration of the weight.
[0003]
[Problems to be solved by the invention]
By the way, as described above, this conventional dynamic vibration absorbing device includes the sliding guide member for the weight, and if the guide surface of the sliding guide member for the weight is not sufficiently smooth, the vibration of the weight will slide. It is transmitted to the structure supporting the sliding guide member via the guide member. This structure is in most cases the object that is currently actually trying to damp the vibration, and thus may cause secondary vibrations in the structure in the case described above. Also, when the sliding guide member is provided, the vibration having a small acceleration cannot overcome the frictional resistance force between the weight and the sliding guide member, and as a result, the vibration energy of the weight is not affected by such vibration. Is transmitted to the sliding guide member as it is without being absorbed by the energy absorbing device, and the vibration having a small acceleration generated in the structure is not effectively attenuated after all. Further, in the conventional dynamic vibration absorbing device, since the sliding guide member is provided as described above, a large installation space is required, and it is difficult to apply to a general house floor or the like.
[0004]
In addition, in many cases, vibration is accompanied by noise, but it is difficult for conventional dynamic vibration absorbers to effectively eliminate the noise.
[0005]
The present invention has been made in view of the above points, and an object of the present invention is to be able to effectively attenuate the vibration of a structure without using a sliding guide member. An object of the present invention is to provide a dynamic vibration absorbing device which is not required and can reduce noise caused by vibration.
[0006]
[Means for Solving the Problems]
The object according to the present invention, as set is the shear stress along the plate surface of the plate-like elastic member by bending of at least a pair of plate-like elastic member and the plate-like elastic member disposed opposite occurs inside A plurality of sets of a combined body including a viscoelastic member rigidly joined to each of the plate- like elastic members by vulcanization bonding and disposed between the plate- like elastic members, and a pair of plate-like elastic members of each set One end is fixed to a substantially central portion of each set of plate-like elastic members so that the pair of plate-like elastic members are supported at an interval from each other with the outer peripheral end of the pair as a free end, and the other end is connected to the vibration source. And a set of plate-like elastic members and the other set of plate-like elastic members are configured to attenuate vibrations having different natural vibration periods. This is achieved by a dynamic vibration absorber.
[0007]
In one preferred example of the present invention, a weight is attached to the plate-like elastic member. By attaching the weight, the period of vibration that can be absorbed by the dynamic vibration absorber can be preferably adjusted. Such adjustment can also be performed by a plate member that sandwiches a pair of plate-shaped elastic members.
[0008]
In another preferred embodiment of the present invention, the plate-like elastic member is formed in a disk shape, and one end of the mounting member is fixed to substantially the center of the plate-like elastic member.
[0009]
As the viscoelastic member in the present invention, a urethane-based polymer material, an olefin-based polymer material, a silicon-based polymer material, a high-damping rubber mixed with asphalt and the like can be exemplified, but other members may be used. Of course. In the case of a viscoelastic member using rubber, the plate-like elastic member is bonded to the plate-like elastic member by vulcanization bonding so that a shear stress along the plate surface of the plate-like elastic member is generated inside by bending the plate-like elastic member . It is not preferred. Needless to say, the combination of the pair of plate-like elastic members and the viscoelastic member may be embodied by a so-called vibration damping steel plate.
[0010]
In the present invention, the combination of the plate-like elastic member and the viscoelastic member one pair attachment member attached to the structure a plurality of sets, the each of the plurality of natural vibration period having the structure each is responsible attenuated form each set of combinations of a pair of plate-like elastic member and the viscoelastic member so as to. However examples of the above combined body is a three-layer structure consisting of a pair of plate-like elastic member and the viscoelastic member, for example, plate-like elastic member and the viscoelastic member and disposed alternately to three layers or more, That is, it is needless to say that a combination of a multilayer plate-like elastic member and a viscoelastic member may be used. In other words, in the present invention, it is only necessary that each combination includes at least a pair of plate-like elastic members disposed to face each other and a viscoelastic member disposed between the plate-like elastic members. It is.
[0011]
In the present invention, as described above, the plate-like elastic member is preferably formed in a disk shape, but is not particularly limited thereto, and may have various shapes such as a square, a rectangle, and an ellipse. The viscoelastic members need not be arranged over the entire space between the plate-like elastic members, but may be arranged in a dispersed manner. In addition, the weight provided for adjusting the vibration period for absorbing the vibration is not necessarily required to be disposed on the peripheral edge of the plate-like elastic member, or over the entire peripheral edge. It is also possible to arrange and provide them.
[0012]
When the dynamic vibration absorbing device of the present invention has a more effective sound absorbing effect, a sound absorbing material such as felt may be attached to the surface of the plate-like elastic member facing the floor or the like, or the plate-like elastic member may have a sound absorbing material. The surface may be an uneven sound absorbing surface.
[0013]
[Action]
The dynamic vibration damping device of the present invention is mounted on a structure, for example, a floor of a house, via a mounting member. Thus, when the floor of the house is vibrated by, for example, walking by a person, the vibration is transmitted to a combination of a pair of plate-like elastic members and a viscoelastic member which are arranged to face each other via an attachment member, and one end of the attachment member is provided. The free end sides of the pair of plate-like elastic members vibrate with the phase shifted by about 90 ° with respect to the natural frequency of the floor. Due to the bending of the plate-like elastic member caused by this vibration, a shear stress is generated inside the visco-elastic member along the plate surface of the plate-like elastic member, and the viscous shear stress of the visco-elastic member generates vibration energy as much as possible. Attenuated quickly. Further, after the vibration of the floor is reduced by the viscous shear stress of the viscoelastic member, the vibration of the plate-like elastic member is rapidly attenuated.
[0014]
Hereinafter, the present invention will be described based on preferred examples shown in the drawings. This will clarify the invention described above and other inventions. The present invention is not limited to these specific examples.
[0015]
【Concrete example】
In FIG. 1, as an example , a dynamic vibration absorber 1 according to the present invention includes a pair of plate-like elastic members 2 and 3 arranged opposite to each other and a viscoelastic member 4 arranged between the plate-like elastic members 2 and 3. One end 6 is fixed to the plate-like elastic members 2 and 3 via a nut 7 so that the pair of plate-like elastic members 2 and 3 are supported using the outer peripheral end 5 of the plate-like elastic members 2 and 3 as a free end. The other end 8 basically has a mounting member 11 mounted on a lower surface 10 of a floor 9 of a house, for example, as a structural body.
[0016]
In this example, the plate-like elastic members 2 and 3 and the viscoelastic member 4 are formed in a disk shape, and one end 6 of the mounting member 11 is connected to the center (fulcrum) of the disk-like plate-like elastic members 2 and 3. It is fixed to. The thickness t of each of the plate-like elastic members 2 and 3, the distance from the fulcrum to the free end, that is, the radius r, and the mass are the period of the vibration to be absorbed, that is, the natural vibration of the floor 9 to which the main dynamic vibration absorbing device 1 is applied. The phase is set to be shifted by 90 ° with respect to the period, and as an example, a thickness of 3 mm, a radius of 250 mm, and a mass of 4.6 kg can be exemplified.
[0017]
The viscoelastic member 4 of this embodiment is made of a thin rubber member, and its both surfaces 12 and 13 are firmly joined to the plate-like elastic members 2 and 3 by vulcanization bonding. Since the viscoelastic member 4 is strongly and firmly joined to the plate-like elastic members 2 and 3, the viscous shear stress is generated along the plate surface of the plate-like elastic member by bending the plate-like elastic members 2 and 3, that is, It is generated inside the viscoelastic member 4 along the direction A.
[0018]
In this example, the mounting member 11 is a rod-shaped portion having a reduced diameter portion 14, in other words, a columnar portion 15, a base 16 connected to the columnar portion 15, and a male screw portion formed at the tip of the columnar portion 15. The through-holes 18, 19 and 20 of the plate-like elastic members 2 and 3 and the viscoelastic member 4 are arranged in the reduced-diameter portion 14, and the nut 7 is screwed into the male screw portion 17. Thereby, the plate-like elastic members 2 and 3 and the viscoelastic member 4 are firmly fixed to one end 6 of the mounting member 11. The base 16 is fixed to the floor 9 as a vibration source via a screw 21 or the like. Thus, the mounting member 11 is mounted at the other end 8 to the lower surface 10 as a vibration surface of the floor 9. The floor 9 generally does not have only one natural vibration period, but has a plurality of vibration modes. Therefore, the dynamic vibration absorber 1 of the present embodiment thus formed has a vibration mode of the vibration mode to be absorbed. It is placed on the floor 9 where the belly is created.
[0019]
The operation will be described below. When vibration in the direction B occurs on the floor 9 due to walking of a person or the like, this vibration is transmitted to the plate-like elastic members 2 and 3 via the mounting member 11, and the plate-like elastic members 2 and 3 As shown in FIG. 2, the phase shifts in the direction C by 90 ° with the one end 6 of the mounting member 11 as a fulcrum, and the vibration causes the plate-like elastic members 2 and 3 to bend. Due to this bending of the plate-like elastic members 2 and 3, viscous shear stress is generated inside the visco-elastic member 4 along the plate surfaces of the plate-like elastic members 2 and 3, that is, along the A direction, Due to the generation of the shearing stress, the vibration energy of the plate-like elastic members 2 and 3 and, consequently, the vibration energy of the floor 9 is attenuated as quickly as possible, and as a result, the vibration of the floor 9 is immediately eliminated.
[0020]
When the disk-shaped plate-like elastic member 2 is used as in this example, the disk-shaped plate-like elastic member 2 functions as a reflection plate against vibration noise generated on the floor 9, so that a sound insulation effect is expected. Can be done. In addition, the sound generated as a result of the vibration generated on the floor 9 and the sound generated as a result of the vibration of the plate-like elastic members 2 and 3 have opposite phases at a position apart from the dynamic vibration absorber 1. When the distance L between the elastic member 2 and the plate-like elastic member 2 is set, in other words, when the length of the mounting member 11 is selected, the dynamic vibration absorbing device 1 also has a sound deadening function. Vibration noise can be effectively reduced. That is, the plate surface of the plate-like elastic member 2 faces the lower surface 10 of the floor 9, and the distance L from the lower surface 10 of the floor 9 to the plate-like elastic member 2 is different from the vibration sound generated by the vibration of the lower surface 10 of the floor 9. When the attachment member 11 is formed so as to have a value set in relation, the dynamic vibration absorber 1 has a sound deadening function and a sound insulation effect, and the vibration noise of the floor 9 can be effectively reduced.
[0021]
By the way, in the dynamic vibration absorbing device 1 of the above example, the vibration mode to be absorbed is adjusted by the thickness, the radius r, the mass, and the like of the plate-like elastic members 2 and 3 and the viscoelastic member 4, but are shown in FIGS. In addition to the above, the annular weights 41 and 42 are attached to the outer peripheral end 5 of the plate-like elastic members 2 and 3 so that the weights 41 and 42 are adjusted so as to operate in a vibration mode in which vibration is to be absorbed. May be configured.
[0022]
As shown in FIGS. 5 and 6, in the present invention, a dynamic vibration absorber 64 having fan-shaped cavities 61, 62 and 63 in the plate-like elastic members 2 and 3 and the viscoelastic member 4 may be used. The dynamic vibration absorbing device 64 in which the places 61, 62 and 63 are formed may have a preferable vibration effective mass and may be preferable. It is to be noted that all of the plate-like elastic members 2 and 3 and the visco-elastic member 4 are not provided with such spaces 61, 62 and 63, for example, only one of the plate-like elastic members 2 and 3 or the visco-elastic member 4 is provided. Such a space may be provided in the vehicle.
[0023]
Further, as shown in FIG. 7, the plate-like elastic members 2 and 3 and the viscoelastic member 4 are firmly moved by a pair of rigid plate members 71 and 72 having a desired diameter inserted into the mounting member 11. The vibration absorbing device 73 may be formed. By using the pair of plate members 71 and 72 in this manner, the distance from the fulcrum to the free end is adjusted, and the period of vibration that can be absorbed by the dynamic vibration absorbing device 73 is reduced. Can be adjusted.
[0024]
Above SL is a basic example of mounting the pair of plate-like elastic member 2 and 3 and combinations thereof comprising a viscoelastic member 4 to the attachment member 11, an example of the present invention, respectively, as shown in FIG. 8 s Three sets of a combination of plate-like elastic members 2 and 3 having different diameters and a viscoelastic member 4 are mounted on the mounting member 11 at intervals by spacers 81 and 82 to form a dynamic vibration absorber 83. According to the present example, the vibrations having a plurality of different natural vibration periods can be attenuated at once by one dynamic vibration absorber 83. In the dynamic vibration absorbing device 83, the diameters of the plate-like elastic members 2 and 3 and the visco-elastic member 4 are made different to attenuate vibrations having a plurality of different natural vibration periods. In the three sets of the combined body composed of 2 and 3 and the viscoelastic member 4, the thickness or the mass thereof is changed, or the weights 41 and 42 or the plate members 71 and 72 are provided to provide vibrations having different natural vibration periods. May be attenuated by one dynamic vibration absorber.
[0025]
Further, as shown in FIG. 9, a plurality of slits 91 extending in the radial direction may be formed in each of the plate-like elastic members 2 and 3 and the viscoelastic member 4 to form the dynamic vibration absorbing device 92. The adjustment of the natural frequency is also possible.
[0026]
【The invention's effect】
According to the present invention, the plate-like elastic member is bent inside the viscoelastic member by bending of the plate-like elastic member caused by the vibration of the free end side of the pair of plate-like elastic members with the one end of the mounting member as a fulcrum. Along with this, a shearing stress is generated, and the vibrational energy is attenuated as quickly as possible by the generation of the shearing stress of the viscoelastic member. Therefore, the vibration can be effectively damped without using a sliding guide member. In addition to that, in addition to requiring less installation space, the noise caused by vibration can be effectively reduced. Moreover, according to the present invention, a plurality of sets of at least a pair of plate-like elastic members and a viscoelastic member are provided, and one set of plate-like elastic members and one set of plate-like elastic members are attached with an interval. Since another set of plate-like elastic members supported by the member attenuate vibrations having different natural vibration periods, vibrations having a plurality of different natural vibration periods can be generated by one dynamic vibration absorber. Energy can be attenuated as quickly as possible and the viscoelastic member is firmly bonded to each of the plate-like elastic members by vulcanization bonding, so that the shear stress along the plate surface of the plate-like elastic member is reduced. The vibration energy can be reliably generated inside the viscoelastic member, and the vibration energy can be attenuated as quickly as possible in combination with the above effects.
[Brief description of the drawings]
FIG. 1 is a side view of one preferred embodiment of the present invention.
FIG. 2 is an operation explanatory diagram of the specific example shown in FIG. 1;
FIG. 3 is a side view of another preferred embodiment of the present invention.
FIG. 4 is a bottom view of the specific example shown in FIG.
FIG. 5 is a bottom view of still another preferred embodiment of the present invention.
6 is a sectional view taken along line VI-VI of the specific example shown in FIG.
FIG. 7 is a side view of a fourth preferred embodiment of the present invention.
FIG. 8 is a side view of a fifth preferred embodiment of the present invention.
FIG. 9 is a bottom view of a sixth preferred embodiment of the present invention.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 dynamic vibration absorber 2 plate elastic member 3 plate elastic member 4 viscoelastic member 9 floor 11 mounting member

Claims

One set is vulcanized to each of the at least one pair of plate-like elastic members and the plate-like elastic members so that a shear stress along the plate surface of the plate-like elastic members is generated inside by bending of the plate-like elastic members. a plurality of sets of comprises a placement viscoelastic member between are joined firmly by adhesive to a plate-like elastic member, a pair of each set as a free end of the outer peripheral end of each set of the pair of plate-like elastic member An attachment member having one end fixed to a substantially central portion of each set of plate elastic members and the other end attached to the vibration source so as to support the plate elastic members at intervals. A dynamic vibration absorber in which one set of plate-like elastic members and another set of plate-like elastic members attenuate vibrations having different natural vibration periods .

The dynamic vibration absorber according to claim 1, wherein a weight that adjusts a period of vibration to be absorbed is attached to the plate-like elastic member.

3. The dynamic vibration absorber according to claim 1, wherein the plate-like elastic member is formed in a disk shape, and one end of the mounting member is fixed to a substantially central portion of the plate-like elastic member.

The dynamic vibration absorber according to any one of claims 1 to 3, wherein the pair of plate-like elastic members are sandwiched between plate members that adjust a cycle of vibration to be absorbed.