JP4272380B2

JP4272380B2 - Anti-vibration structure of anisotropic damper and mechanical chassis

Info

Publication number: JP4272380B2
Application number: JP2002008295A
Authority: JP
Inventors: 正幸板倉
Original assignee: Polymatech Co Ltd
Current assignee: Polymatech Co Ltd
Priority date: 2002-01-17
Filing date: 2002-01-17
Publication date: 2009-06-03
Anticipated expiration: 2022-01-17
Also published as: JP2003206989A

Description

【０００１】
【発明の属する技術分野】
この発明は、振動伝達経路にあって振動を減衰させるダンパーに関する。より具体的には、車載用、民生用を含めた音響機器、映像機器、情報機器、各種精密機器等に用いられるＣＤ等の光ディスク、ＭＯ等の光磁気ディスク、ハードディスク等の磁気ディスクといったような、各種ディスク状記録媒体の非接触読取り機構を実装するメカニカルシャーシと、それを囲う外装部材との間で伝達される外乱振動や内乱振動を減衰させるのに好適なダンパーと、該メカニカルシャーシの防振構造に関するものである。
【０００２】
【従来の技術】
前述のようなディスク状記録媒体（以下、単に「ディスク」と略称する。）については、記録されたデータが光学ピックアップや磁気ヘッドを利用して非接触方式で読取られる。このような非接触読取り機構はメカニカルシャーシに実装されているが、メカシャーシを外装部材に備える前述のような各種機器については、読取り方式が非接触であるが故に様々な防振対策が施されており、その一例としては、外装部材とメカニカルシャーシとの間にダンパーを介在させて、メカニカルシャーシを浮動状態で弾性的に防振支持する例が知られている。
【０００３】
図７で示すのはその第１の従来例であり、１が外装部材で、２がメカニカルシャーシである。このメカニカルシャーシ２にはディスク３が装着され、ディスク３に記録されたデータはメカニカルシャーシ２に実装された非接触読取り機構によって読み出されることになる。メカニカルシャーシ２と外装部材１との間にはダンパー４が取付けられている。ダンパー４は、図８で示すような円筒形状のインシュレータタイプのもので、スチレン系エラストマーのようなゴム状弾性体で形成されている。ダンパー４には、その軸線に沿って挿通孔４ａが貫通形成されており、ここに挿通させたネジＮが外装部材１に螺着することで、ダンパー４が外装部材１に対して固着される。また、ダンパー４には小径の凹部４ｂが形成されており、ここに凹部４ｂに対してメカニカルシャーシ２の取付部２ａが係合することで、ダンパー４はメカニカルシャーシ２に対して固着される。第１の従来例にあっては、このようなインシュレータタイプのダンパー４を３つ用いて、外装部材１に対してメカニカルシャーシ２を浮動状態で弾性的に防振支持する構造となっている。
【０００４】
また、図９で示すのは第２の従来例で、この従来例におけるダンパー５は、図１０で示すように、ポリプロピレン等の硬質樹脂にて形成された略円筒状の周壁部材６と、熱可塑性エラストマーのようなゴム状弾性体にて形成され、周壁部材６の一端側開口部を閉塞する可撓部材７と、ポリプロピレン等の硬質樹脂にて形成され、周壁部材６の他端側開口部を閉塞する蓋部材８と、それらの各部材により形成される内部空間に封入したシリコーンオイル等からなる振動減衰に作用する粘性流体９と、により構成されている。ゴム状弾性体でなる可撓部材７には、取付凹部７ａが形成されており、メカニカルシャーシ１０は、その側壁部１０ａに突設した支持軸１０ｂが該取付凹部７ａに挿入されて保持されることで、ダンパー５とコイルスプリングＳによって防振支持される構造となっている。そして、ダンパー５は、蓋部材８に形成した挿通孔８ａにネジＮが挿通され、このネジＮが外装部材１のネジ孔に螺合することで、外装部材１に対して固定される。第２の従来例にあっては、このような粘性流体封入式のダンパー５を３つ用いて、外装部材１に対してメカニカルシャーシ１０を浮動状態で弾性的に防振支持する構造となっている。
【０００５】
【発明が解決しようとする課題】
ところで、ノートブックタイプのパーソナルコンピュータや携帯型の電子機器等については、特に機器全体の薄型化の傾向が著しく、狭い内部空間での防振対策が急速に求められてきている。前述した第１の従来例や第２の従来例は、そのような狭い内部空間での防振対策にも対応できるようにするためのものであり、要望に見合った防振特性を発揮できるものとなっている。即ち、第１の従来例にあっては、比較的高さを低く設定できるインシュレータタイプのダンパー４を用いるので、縦方向ｙでの外装部材１の薄型化に対応可能である。また第２の従来例にあっては、ダンパー５の蓋部材８を外装部材１の側板部１ａに固定し、ダンパー５を横方向ｘにそって横向きに取付けているので、例えばダンパー５を外装部材１の底板部１ｂに取付けるような場合と比べて、縦方向ｙで外装部材１を薄型化することができる。
【０００６】
しかしながら、最近では機器全体の更なる薄型化を求める声が多く、前述の第１の従来例や第２の従来例のものをそのまま適用したのでは、満足できる防振特性を発揮することが難しくなってきている。即ち、これらの従来例で減衰効果を向上するには、第１の従来例のダンパー４については硬度が低いゴム状弾性体（スチレン系エラストマー）を用い、また第２の従来例のダンパー５については可撓部材７をなすゴム状弾性体（熱可塑性エラストマー）の硬度を低くしたり、粘性流体９の粘度を下げるようにすることが考えられる。ところが、機器全体の更なる薄型化を実現するために、外装部材１内部に備える各種部品どうしの隙間が更に狭小となってきているため、ディスク３が高速回転した時に生じる浮力、外乱振動、内乱振動によってディスク３自体とメカニカルシャーシ２，１０が縦方向ｙで浮上し、振動を受けて浮動状態で遊動することで、外装部材１の内面や周囲の各種部品に対して接触する可能性がある、という問題があった。
【０００７】
この問題を回避するためには、例えば第１の従来例にあっては、図８（ｂ）で示すダンパー１２のように、大径の上部と下部を高弾性部１２ａにて形成し、小径の中間部を低弾性部１２ｂにて形成することが考えられる。即ち、高弾性部１２ａで縦方向ｙの振動減衰を、低弾性部１２ｂで横方向ｘの振動減衰を行うようにし、全体としては高弾性部１２ａにてディスク３やメカニカルシャーシ２の上下方向の変位を抑えるようにするのである。しかしながら、これでは高弾性部１２ａの影響で外部振動に対する減衰効果が悪化してしまう問題があり、このインシュレータタイプのダンパー４，１２では、防振特性を損なわずにより機器全体の更なる薄型化に対応するための更なる他の改善策は期待できなかった。
【０００８】
また、第２の従来例にあっては、可撓部材７をなすゴム状弾性体の硬度や粘性流体９の粘度を高くすれば前述の接触問題を解決できるが、やはり第１の従来例と同様に外部振動に対する減衰効果が低減してしまう。
【０００９】
以上のような従来例とその改善策を背景になされたのが本発明であって、その目的とするところは、防振特性を損なうことなく機器全体の更なる薄型化に対応することができるようなダンパーとメカニカルシャーシの防振構造を提供することにあり、その手段は以下のとおりである。
【００１０】
【課題を解決するための手段】
即ち、筒状の周壁部材と、周壁部材の一端に固着して一端側開口を閉塞するゴム状弾性体でなる可撓部材と、周壁部材の他端に固着して他端側開口を閉塞する蓋部材と、
周壁部材、可撓部材、蓋部材により形成される内部空間に封入した粘性流体とを備えており、蓋部材か可撓部材の何れか一方がディスク状記録媒体の非接触式読取り機構を実装しその上面にディスク装着面を有するメカニカルシャーシの側方位置に対して取付けられ、前記何れか他方がメカニカルシャーシの側方位置で該メカニカルシャーシを囲む外装部材に対して取付けられて、メカニカルシャーシを外装部材に対して浮動状態で防振支持するダンパーについて、周壁部材が、矩形角筒状の硬質樹脂でなり、可撓部材が、前記取付状態でメカニカルシャーシの略面直方向にそわせる垂直部と、該垂直部よりも長さが長く該メカニカルシャーシの略面方向にそわせる水平部とを有し、該略面直方向でばね定数が硬く、該略面方向でばね定数が軟らかい矩形ドーム形状となっており、矩形ドーム形状の可撓部材の環状端末部は、矩形角筒状の周壁部材の一端に固着されており、矩形ドーム形状の可撓部材の頂部には、粘性流体が充填された前記内部空間に向けて突出し、メカニカルシャーシ又は外装部材から突出するピン状の支持軸を差込ませて保持する軸保持部を有しており、可撓部材の垂直部及び水平部は、環状端末部とピン状の支持軸を保持する軸保持部との間で、支持軸を中心とする軸交差方向で異方性を有する前記略面直方向と前記略面方向への弾性変形によってメカニカルシャーシの振動を減衰させることを特徴とする異方性ダンパーである。
【００１１】
この異方性ダンパーは、可撓部材のうち、メカニカルシャーシの略面直方向にそう縦方向に対応する部位についてはばね定数を硬くし、メカニカルシャーシの略面方向にそう横方向に対応する部位についてはばね定数を軟らかくすることで、ディスクが高速回転した際の浮力や内乱振動、外乱振動によって生じるメカニカルシャーシと外装部材との相対変位を抑制しつつ高い減衰効果を発揮するものである。
【００１２】
即ち、可撓部材をなすゴム状弾性体については所望の防振特性を満足する所定の硬度をもたせつつ、前記縦方向については垂直部の長さを短くしてばね定数が硬くされており、前記横方向（水平方向）については水平部の長さを垂直部よりも長くしてばね定数が軟らかくされている。したがって、第２の従来例のように、振動に対する減衰効果をやむなく損なわせる方向性で可撓部材の硬度を高める必要がなく、また粘性流体封入式のダンパーにあっては粘性流体の粘度を高める必要がなく、所望の防振特性を発揮できるような硬度や粘度にしたままであっても、ディスクとメカニカルシャーシに働く浮力を抑制しつつ高い減衰効果を発揮することができる。なお、この本発明の異方性ダンパーは、粘性流体封入式のダンパーとして、また周壁部材等に通気孔を設けそこを内外で流出入する空気抵抗によって振動減衰効果を発揮するエアーダンパーについても適用することができる。
【００１３】
また、本発明は、前記異方性ダンパーについて、前記水平部の肉厚を垂直部の肉厚よりも厚肉に形成したものである。
【００１４】
水平部の肉厚を垂直部の肉厚よりも厚肉としたため、メカニカルシャーシと外装部材の縦方向での相対変位に対する抑えを強めることができ、更に該変位を小さく抑制することができる。
【００１５】
さらに本発明は、前記異方性ダンパーについて、前記周壁部材の一端側開口部に固着する環状端末部側の肉厚よりも頂部側の肉厚を薄肉として前記水平部を形成したものである。
【００１６】
水平部の肉厚を等厚とせずに、環状端末部側の肉厚よりも頂部側の肉厚を薄肉としたため、周壁部材との固着側であって減衰性能に与える悪影響が比較的少ない厚肉の環状端末部側によって縦方向におけるばね定数が硬くされて、メカニカルシャーシと外装部材との縦方向の相対変位を抑制することができる。そして、横方向については、薄肉の頂部側によって振動減衰性能を高めることができる。したがって、肉厚を等厚とした可撓部材よりも振動減衰性能と浮力抑制とをバランス良く発揮することができる。
【００１７】
この場合、可撓部材の水平部は、環状端末部側から頂部側にかけて肉厚が漸次変化するようにしたものであっても、また肉厚が段差部を境に面差をもって変化するようにしたものであってもよい。
【００１８】
また、上記目的を達成する本発明は、筒状の周壁部材と、周壁部材の一端に固着して一端側開口部を閉塞するゴム状弾性体でなる可撓部材と、周壁部材の他端に固着して他端側開口を閉塞する蓋部材と、周壁部材、可撓部材、蓋部材により形成される内部空間に封入した粘性流体とを備えるダンパーを、蓋部材か可撓部材の何れか一方をディスク状記録媒体の非接触式読取り機構を実装しその上面にディスク装着面を有するメカニカルシャーシの側方位置に対して取付け、前記何れか他方をメカニカルシャーシの側方位置で該メカニカルシャーシを囲む外装部材に対して取付けて、該ダンパーでメカニカルシャーシを外装部材に対して浮動状態で防振支持するメカニカルシャーシの防振構造について、前記ダンパーの周壁部材が、矩形角筒状の硬質樹脂でなり、前記ダンパーの可撓部材が、前記取付状態でメカニカルシャーシの略面直方向にそわせる垂直部と、該垂直部よりも長さが長く該メカニカルシャーシの略面方向にそわせる水平部とを有し、該略面直方向でばね定数が硬く、該略面方向でばね定数が軟らかい矩形ドーム形状となっており、矩形ドーム形状の可撓部材の環状端末部が、矩形角筒状の周壁部材の一端に固着されており、矩形ドーム形状の可撓部材の頂部には、粘性流体が充填された前記内部空間に向けて突出し、メカニカルシャーシ又は外装部材から突出するピン状の支持軸を差込ませて保持する軸保持部を有しており、可撓部材の垂直部及び水平部は、環状端末部とピン状の支持軸を保持する軸保持部との間で、支持軸を中心とする軸交差方向で異方性を有する前記略面直方向と前記略面方向への弾性変形によってメカニカルシャーシの振動を減衰させることを特徴としている。
【００１９】
このメカニカルシャーシの防振構造によれば、ダンパーの可撓部材が長手方向で長さの短い垂直部と長さの長い水平部とを有する矩形ドーム形状となっており、且つ、該垂直部をメカニカルシャーシの略面直方向にそわせて取付け、該水平部をメカニカルシャーシの略面方向にそわせて取付けたので、可撓部材をなすゴム状弾性体については所望の防振特性を満足する所定の硬度をもたせつつ、前記縦方向については垂直部の長さを短くしてばね定数が硬くされており、前記横方向（水平方向）については水平部の長さを垂直部よりも長くしてばね定数が軟らかくされる。したがって、第２の従来例のように、振動に対する減衰効果をやむなく損なわせる方向性で可撓部材の硬度を高める必要がなく、また粘性流体封入式のダンパーにあっては粘性流体の粘度を高める必要がなく、所望の防振特性を発揮できるような硬度や粘度にしたままであっても、ディスクとメカニカルシャーシに働く浮力を抑制しつつ高い減衰効果を発揮することができる。
【００２０】
この場合、ダンパーの具体的な取付形態としては、メカニカルシャーシに縦方向（上下方向）にそう側壁部を設け、この側壁部にダンパーの周壁部材の他端側開口部を閉塞する蓋部材をネジ止め等の固着手段により固着し、また外装部材に支持軸を内向きに突設するとともに、ダンパーの可撓部材に形成した取付凹部に該支持軸を挿入して保持するようにして、外装部材とメカニカルシャーシとの間にダンパーを取付ける構造とすることができる。また、これとは逆に、ダンパーの蓋部材を外装部材の側板部内面に固着し、ダンパーの可撓部材の取付凹部にメカニカルシャーシの前記側壁部に突設した支持軸を挿入して保持するようにしたダンパーの取付構造としてもよい。
【００２１】
また、本発明は、上記メカニカルシャーシの防振構造におけるダンパーについて、前記水平部の肉厚を垂直部の肉厚よりも厚肉に形成したものである。
【００２２】
水平部の肉厚を垂直部の肉厚よりも厚肉としたため、メカニカルシャーシと外装部材の縦方向での相対変位に対する抑えを強めることができ、更に該変位を小さく抑制することができる。
【００２３】
さらに本発明は、上記前記メカニカルシャーシの防振構造におけるダンパーについて、前記周壁部材の一端側開口部に固着する環状端末部側の肉厚よりも頂部側の肉厚を薄肉として前記水平部を形成したものである。
【００２４】
水平部の肉厚を等厚とせずに、環状端末部側の肉厚よりも頂部側の肉厚を薄肉としたため、周壁部材との固着側であって減衰性能に与える悪影響が比較的少ない厚肉の環状端末部側によって縦方向におけるばね定数が硬くされて、メカニカルシャーシと外装部材との縦方向の相対変位を抑制することができる。そして、横方向については、薄肉の頂部側によって振動減衰性能を高めることができる。したがって、肉厚を等厚とした可撓部材よりも振動減衰性能と浮力抑制とをバランス良く発揮することができる。
【００２５】
【発明の実施の形態】
以下、図面を参照しつつ本発明の実施形態を説明する。なお、各実施形態で同じ部材については共通する符号を用いて重複説明を省略する。
【００２６】
第１実施形態〔図１〜図３〕
【００２７】
この実施形態の異方性ダンパー２１は、筒状の周壁部材２２と、可撓部材２３と、蓋部材２４と、これらによって形成される内部空間に封入された粘性流体９によって構成されている。
【００２８】
周壁部材２２は、図１でその平面図を示すように、垂直部２２ａと水平部２２ｂとを有する略矩形状に形成されている。垂直部２２ａは、外装部材１への取付状態でその長さ方向を縦方向ｙにそわせて取付けられ、また水平部２２ｂは、その長さ方向を横方向ｘにそわせて取付けられる。
【００２９】
この周壁部材２２の素材としては、剛性のあるものが好ましく、目的とする部品の寸法精度、耐熱性、機械的強度、耐久性、信頼性などの要求性能に応じて熱可塑性樹脂、熱硬化性樹脂、金属などから選択することが可能である。その一例を挙げると、熱可塑性樹脂としては、ポリエチレン樹脂、ポリプロピレン樹脂、ポリ塩化ビニル樹脂、ポリスチレン樹脂、アクリロニトリル・スチレン・アクリレート樹脂、アクリロニトリル・ブタジエン・スチレン樹脂、ポリアミド樹脂、ポリアセタール樹脂、ポリカーボネート樹脂、ポリエチレンテレフタレート樹脂、ポリブチレンテレフタレート樹脂、ポリフェニレンオキシド樹脂、ポリフェニレンサルファイド樹脂、ポリウレタン樹脂、ポリフェニレンエーテル樹脂、変性ポリフェニレンエーテル樹脂、シリコーン樹脂、ポリケトン樹脂、液晶ポリマー等やそれらの複合材を利用できる。また、熱硬化性樹脂としては、フェノール樹脂、エポキシ樹脂、シリコーン樹脂、ポリウレタン樹脂、メラミン樹脂、不飽和ポリエステル樹脂等やそれらの複合材を利用できる。金属としては、ステンレス、各種ダイキャストを利用できる。
【００３０】
以上のような周壁部材２２の一端側開口部に環状端末部２３ａを固着した可撓部材２３は、周壁部材２２と同様に矩形ドーム形状に形成されていて、その肉厚は全体的に各部位において等厚である。
【００３１】
この可撓部材２３には、取付状態でメカニカルシャーシ１０の上面１０ｃの面直方向、即ち縦方向ｙにそわせる長さｄ２の垂直部２３ｂと、メカニカルシャーシ１０の面方向、即ち横方向ｘ（なお、図３では説明の便宜上、外装部材１の長手方向を横方向ｘとして示しているが、横方向ｘには紙面に対する垂直方向も含まれる。）にそわせる長さｄ１の水平部２３ｃが形成されている。
【００３２】
各垂直部２３ｂには、屈曲部２３ｄを境に膨出形状の湾曲部２３ｅ，２３ｆが形成されている。可撓部材２３は矩形ドーム形状となっているため、湾曲部２３ｅは湾曲部２３ｆよりも長さ方向で短くされている。また、各水平部２３ｃにも屈曲部２３ｄを境に膨出形状の湾曲部２３ｇ，２３ｈが長さを異ならせて形成してある。これらの垂直部２３ｂと水平部２３ｃは、それらが交わる４カ所の隅部２３ｉにおいて膨出形状の湾曲面をもって連続している。
【００３３】
そして、垂直部２３ｂと水平部２３ｃとが収束する頂部２３ｋは平坦部とされており、その中心部位には周壁部材２２の内方へ突出する軸保持部２３ｍが形成されている。メカニカルシャーシ１０は、その側壁部１０ａの支持軸１０ｂが、該軸保持部２３ｍの取付凹部２３ｎに差込まれて保持されることで、異方性ダンパー２１に対して取付けられる。
【００３４】
ここで可撓部材２３の素材として要求される特性を説明すると、耐久物性と減衰特性が高く、クリープ特性が少ないものが好ましい。具体的には、耐久物性については、ゴム引っ張り物性が２ＭＰａ以上、好ましくは４ＭＰａ以上が好適である。また減衰特性については、損失係数ｔａｎδが０．０５以上（２５℃）、好ましくは０．２以上の高減衰材が好適である。損失係数ｔａｎδが０．０５未満であると、共振時のメカニカルシャーシ１０の振幅が大きくなってしまい、外装部材１と接触するおそれがあるからである。更にクリープ特性については、圧縮永久歪み（７０℃×２２時間）が５０％以下、好ましくは３０％以下の低クリープ特性のものが好適である。圧縮永久歪み（７０℃×２２時間）が５０％よりも大きくなると、長時間放置した後のメカニカルシャーシ１０の変位量が大きくなって外装部材１と接触するおそれがあるからである。
【００３５】
以上のような特性が必要な可撓部材２３の素材は、目的とする部品の寸法精度、耐熱性、機械的強度、耐久性、信頼性、防振特性、制振特性などの要求性能に応じて熱可塑性エラストマー、架橋ゴム等から選択することができる。その一例を挙げると、熱可塑性エラストマーとしては、スチレン系熱可塑性エラストマー、オレフィン系熱可塑性エラストマー、ポリエステル系熱可塑性エラストマー、ポリウレタン系熱可塑性エラストマー、ポリアミド系熱可塑性エラストマー、塩化ビニル系熱可塑性エラストマー等を利用できる。また架橋ゴムとしては、天然ゴム、ブタジエンゴム、イソプレンゴム、スチレンブタジエン共重合ゴム、ニトリルゴム、水添ニトリルゴム、クロロプレンゴム、エチレンプロピレンゴム、塩素化ポリエチレン、クロロスルホン化ポリエチレン、ブチルゴムおよびハロゲン化ブチルゴム、アクリルゴム、フッ素ゴム、ウレタンゴム、シリコーンゴム等を利用できる。
【００３６】
蓋部材２４は、周壁部材２２の他端側開口部を閉塞するもので、周壁部材２２の外向きフランジ２２ｃと相対形状として形成されており、超音波溶着によって該外向きフランジ２２ｃに対して固着される。その素材は周壁部材２２と同様である。
【００３７】
次に、異方性ダンパー２１の取付構造を説明する。異方性ダンパー２１は、図３で示すように、可撓部材２３の垂直部２３ｂをメカニカルシャーシ１０の上面１０ｃの面直方向、即ち縦方向ｙにそわせて取付け、水平部２３ｃをメカニカルシャーシ１０の面方向、即ち横方向ｘにそわせて取付けるようにする。その取付けにあたっては、蓋部材２４を外装部材１の側板部１ａに対して接着により固着させる。なお、接着でなくても蓋部材２４を外装部材１の側板部１ａに対してネジ止めしたり、蓋部材２４あるいは周壁部材２２にかぎ爪状の係合片を設け、これを外装部材１に係合させることで固着させたり、逆に外装部材１にかぎ爪状の係合片を設け、これを蓋部材２４や周壁部材２２に係合させることで固着してもよい。こうした機械的固着手段の他、融着や溶着のような化学的固着手段で固着してもよい。また、コイルスプリングＳを異方性ダンパー２１を取り囲むようにして、メカニカルシャーシ１０の支持軸１０ｂを、異方性ダンパー２１の可撓部材２３の取付凹部２３ｎに差込んで保持させる。この実施形態では、メカニカルシャーシ１０を３つの異方性ダンパー２１で防振支持させるので、以上のような取付作業を３つの異方性ダンパー２１について行うことで、図３で示すような異方性ダンパー２１の取付構造が得られることになる。
【００３８】
次に、第１実施形態による異方性ダンパー２１とその取付構造による作用・効果について説明する。
【００３９】
異方性ダンパー２１の可撓部材２３は、メカニカルシャーシ１０の面直方向にそう縦方向ｙについては、長さｄ２が短くばね定数が硬くされており、メカニカルシャーシ１０の面方向にそう横方向ｘについては、長さｄ１が垂直部２３ｂよりも長くばね定数が軟らかくされている。そのため、内乱振動や外乱振動、あるいはディスク３が高速回転した際の浮力等を起因として生じる縦方向ｙにおける外装部材１とメカニカルシャーシ１０との相対変位は抑制され、振動は減衰される。したがって、前述した従来例のように、振動に対する減衰効果をやむなく損なわせる方向性で可撓部材２３の硬度を高めたり、粘性流体９の粘度を高める必要がなく、所望の防振特性を発揮できるような硬度や粘度にしたままであっても、ディスク３とメカニカルシャーシ１０との相対変位を抑制しつつ高い減衰効果を発揮することができる。
【００４０】
第２実施形態〔図４、図５、図３〕
【００４１】
この実施形態の異方性ダンパー３１は、第１実施形態の異方性ダンパー２１と比較すると、周壁部材３２と可撓部材３３の構成が異なっている。なお、それ以外の異方性ダンパー３１の構成とその取付構造については、第１実施形態と同様である。
【００４２】
異方性ダンパー３１を構成する周壁部材３２は、垂直部３２ａの幅（肉厚）ｄ３と水平部３２ｂの幅（肉厚）ｄ４とを異ならせてある。これは周壁部材３２の開口端３２ｃに固着させる可撓部材３３の環状端末部３３ａの形状に対応させたものである。即ち、この実施形態の可撓部材３３は、垂直部３３ｂの肉厚ｄ５は全体的に等厚だが（図５（ｂ））、図４（ｂ）において軸保持部３３ｄの取付凹部３３ｅを挟んで上下に示す二点鎖線で囲った斜線領域Ｒに相当する水平部３３ｃの肉厚は、環状端末部３３ａにおいて垂直部３３ｂの肉厚ｄ５よりも厚く最も厚肉となっており、そこから垂直部３３ｂの肉厚ｄ５と等厚の平坦な頂部３３ｆにかけて漸次薄肉となるように形成されている（図５（ａ））。そして、可撓部材３３の裏面における垂直部３３ｂと水平部３３ｃとの境界部分（図４で示す二点鎖線の部分）では、厚肉の水平部３３ｃから薄肉の垂直部３３ｂにかけて傾斜面となっている。
【００４３】
以上のように、この実施形態の異方性ダンパー３１の可撓部材３３における特徴は、垂直部３３ｂと水平部３３ｃとで肉厚が異なり、さらに水平部３３ｃについては環状端末部３３ａから頂部３３ｆにかけて肉厚を変化させていることにある。そして、異方性ダンパー３１は、この構成によって第１実施形態の異方性ダンパー２１の作用・効果に加えて、次の作用・効果を発揮できる。即ち、水平部３３ｃは、周壁部材３２と固着されて振動減衰性能に与える影響が比較的少ない厚肉の環状端末部３３ａ側でばね定数が硬く、そこから頂部３３ｆにかけて漸次薄肉化されることで取付凹部３３ｅ側でばね定数が軟らかくなる。そのため、ばね定数が硬い水平部３３ｃの環状端末部３３ａ側では、更に外装部材１とメカニカルシャーシ１０の縦方向ｙの相対変位に対する抑えが強く、該変位を更に小さく抑制することができる。そして、ばね定数が軟らかい水平部３３ｃの取付凹部３３ｅ側では、横方向ｘにおける変形が柔軟であり高い減衰性能を発揮することができる。
【００４４】
第３実施形態〔図６〕
【００４５】
この実施形態の異方性ダンパー４１は、第２実施形態の異方性ダンパー３１の変形例であり、可撓部材４２の水平部４２ａの構成がそれと異なるのみで、他の構成については第２実施形態と同様である。即ち、その可撓部材４２は、水平部４２ａが環状端末部４２ｂから頂部４２ｃにかけて等厚で、且つ、垂直部４２ｄよりも厚肉に形成されている。そして、可撓部材４２の裏面における水平部４２ａと垂直部４２ｄとの境界部分（図６（ａ）で示す破線部分）では、厚肉の水平部４２ａから薄肉の垂直部４２ｄにかけて段差部４２ｅを形成したものとなっている。
【００４６】
そして、この第３実施形態の異方性ダンパー４１によれば、第２実施形態の異方性ダンパー３１と比較すると、水平部４２ａが垂直部４２ｄよりも厚肉であり、且つ、その肉厚が等厚であるため、外装部材１とメカニカルシャーシ１０の縦方向ｙの相対変位に対する抑えが更に強くなり、該変位が更に小さく抑制されることになる。
【００４７】
次に、実施例について説明する。
【００４８】
【実施例１】
実施例１は、前述した第１実施形態の異方性ダンパー２１に対応しており、その取付構造は図３で示すとおりである。
【００４９】
具体的には、ポリプロピレン樹脂とスチレン系熱可塑性エラストマーを２色成形して、周壁部材（２２）と可撓部材（２３）とを作製した。そしてその中に粘性流体（９）を注入した後、外向きフランジ（２２ｃ）とポリプロピレン樹脂でなる蓋部材（２４）とを超音波融着することで密閉し、異方性ダンパー（２１）を得た。
【００５０】
可撓部材（２３）の環状端末部（２３ａ）は長方形状とし、その長手方向を１０ｍｍ、短手方向を６．５ｍｍとした。また、可撓部材（２３）の肉厚は０．３ｍｍで等厚とした。さらに、可撓部材（２３）をなすスチレン系熱可塑性エラストマーは、硬度３０（ＪＩＳＫ６２５３タイプＡ）、圧縮永久歪み３０％、損失係数ｔａｎδが０．２０（２５℃）であるものを使用した。また、粘性流体（９）としては、回転粘度１．２ｍ^２／ｓのシリコーングリスを使用した。
【００５１】
【実施例２】
実施例２は、前述した第２実施形態の異方性ダンパー３１に対応しており、その取付構造は図３と同じである。
【００５２】
実施例２では、可撓部材（３３）の垂直部（３３ｂ）の肉厚が０．３ｍｍで、水平部（３３ｃ）の肉厚が最も厚い環状端末部（３３ａ）で０．６ｍｍである異方性ダンパー（３１）とした。なお、水平部（３３ｃ）は、最も厚肉の環状端末部（３３ａ）から頂部（３３ｆ）にかけて、漸次薄肉となるようにした。この可撓部材（３３）の肉厚を除く他の構成は実施例１の異方性ダンパー（２１）と同じである。
【００５３】
【実施例３】
実施例３は、前述した第２実施形態の異方性ダンパー３１に対応しており、その取付構造は図３と同じである。
【００５４】
実施例３では、可撓部材（３３）の垂直部（３３ｂ）の肉厚が０．３ｍｍで、水平部（３３ｃ）の肉厚が最も厚い環状端末部（３３ａ）で０．９ｍｍである異方性ダンパー（３１）とした。なお、水平部（３３ｃ）は、最も厚肉の環状端末部（３３ａ）から頂部（３３ｆ）にかけて、漸次薄肉となるようにした。この可撓部材（３３）の肉厚を除く他の構成は実施例１の異方性ダンパー（２１）と同じである。
【００５５】
【比較例１】
比較例１は、図８（ｂ）に示すダンパー１２に対応しており、その取付構造は図７に示すとおりである。
【００５６】
比較例１のダンパー（１２）は、硬度９０（ＪＩＳＫ６２５３タイプＡ）のスチレン系エラストマーによる高弾性部（１２ａ）と硬度３０（ＪＩＳＫ６２５３タイプＡ）のスチレン系エラストマーによる低弾性部（１２ｂ）とを２色成形により作製したものである。
【００５７】
【比較例２】
比較例２は、図１０のダンパー５に対応しており、その取付構造は図９に示すとおりである。
【００５８】
比較例２のダンパー（５）は、周壁部材（６）と可撓部材（７）の形状、可撓部材（７）の肉厚を０．３ｍｍで等厚とした点が実施例１の異方性ダンパー（２１）と異なるだけで、残余の構成はそれと同じである。
【００５９】
以上の各実施例および比較例について評価試験を行った。評価試験の方法は振動試験である。その条件は次のとおりである。各実施例ではそれぞれ異方性ダンパー（２１，３１）を３つ用いて重量７０ｇのメカニカルシャーシ（１０）を図３で示す取付構造にて防振支持するようにした。また、比較例１では、３つのダンパー（１２）を用いて重量７０ｇのメカニカルシャーシ（２）を図７で示す取付構造にて防振支持するようにした。比較例２では３つのダンパー（５）を用いて重量７０ｇのメカニカルシャーシ（１０）を図９で示す取付構造にて防振支持するようにした。そして、外装部材１にメカニカルシャーシ（１０，２）を備える各実施例および各比較例のディスク再生装置は、加振テーブルに固定されている。
【００６０】
加振テーブルを上下方向（縦方向ｙ）および左右方向（横方向ｘ）に一定加速度５ｍ／ｓ^２で周波数１０〜５００Ｈｚの範囲で振動させ、メカニカルシャーシ（１０，２）への振動伝達率を測定することによってメカニカルシャーシ（１０，２）の変位量を共振周波数にて測定した。共振倍率は、共振周波数において、加振テーブルからの振動入力加速度ａ_１に対しメカニカルシャーシ（１０，２）からの振動出力加速度ａ_２を測定し、２０Ｌｏｇ（ａ_１／ａ_２）の関係式で換算した。また、ディスク（３）を高倍速回転（９６００ｒｐｍ）させた時の外部への振動漏れをＧセンサーにて測定した。この振動試験の結果を表１に示す。
【００６１】
【表１】

【００６２】
実施例１〜実施例３と比較例１とを比べると、比較例１では、ダンパーがインシュレータタイプのものであるために、振動減衰性能におけるすべての評価で実施例１〜３に対して劣っていることが分かる。また、上下方向の変位量については実施例１よりも優れるものの、必要な振動減衰性能を兼ね備えて発揮できるものとはなっていない。
【００６３】
実施例１〜実施例３と比較例２とを比べると、比較例２では、振動減衰性能における評価では実施例１〜３と同じ評価が得られたが、上下方向の変位量については明らかに実施例１〜３よりも大きく劣っており、また外部への振動漏れについても劣っていることが分かる。
【００６４】
したがって、実施例１〜実施例３によれば、振動減衰性能を減殺することなく、メカニカルシャーシの上下方向の変位量を大幅に抑制することができ、更なる機器の薄型化にも対応できる。
【００６５】
【発明の効果】
本発明の異方性ダンパーによれば、可撓部材をなすゴム状弾性体について所望の防振特性を満足する所定の硬度をもたせながらも、縦方向については長さの短い垂直部によってばね定数が硬くされており、前記横方向（水平方向）については長さが垂直部よりも長い水平部によってばね定数が軟らかくされている。したがって、所望の防振特性を発揮できるような硬度や粘度にしたままであっても、ディスクとメカニカルシャーシの変位を抑制しつつ高い減衰効果を発揮することができ、メカニカルシャーシを備える各種機器の更なる薄型化に対応することができる。
【００６６】
水平部の肉厚を垂直部の肉厚よりも厚肉とした本発明によれば、メカニカルシャーシと外装部材の縦方向での相対変位に対する抑えを強めることができ、更に該変位を小さく抑制することができる。
【００６７】
水平部の肉厚を等厚とせずに、環状端末部側の肉厚よりも頂部側の肉厚を薄肉とした本発明によれば、周壁部材との固着側であって減衰性能に与える悪影響が比較的少ない厚肉の環状端末部側によって縦方向におけるばね定数が硬くされて、メカニカルシャーシと外装部材との縦方向の相対変位を抑制することができる。そして、横方向については、薄肉の頂部側によって振動減衰性能を高めることができる。したがって、肉厚を等厚とした可撓部材よりも振動減衰性能と浮力抑制とをバランス良く発揮することができる。
【図面の簡単な説明】
【図１】第１実施形態によるダンパーの正面図。
【図２】図１のダンパーの断面図で、分図（ａ）はＳＢ−ＳＢ線に沿う断面図、分図（ｂ）はＳＣ−ＳＣ線に沿う断面図。
【図３】第１実施形態〜第３実施形態のダンパーを用いるメカニカルシャーシの防振構造の説明図。
【図４】第２実施形態によるダンパーの説明図で、分図（ａ）は周壁部材の正面図、分図（ｂ）は可撓部材の正面図。
【図５】第２実施形態によるダンパーの断面図で、分図（ａ）は図４のＳＤ−ＳＤ線に沿うダンパーの断面図、分図（ｂ）は図４のＳＥ−ＳＥ線に沿うダンパーの断面図。
【図６】第３実施形態によるダンパーの説明図で、分図（ａ）は正面図、分図（ｂ）は分図（ａ）のＳＦ−ＳＦ線に沿う断面図。
【図７】第１の従来例によるメカニカルシャーシの防振構造の説明図。
【図８】図７の防振構造で用いるダンパーの部分断面を含む外観斜視図で、分図（ａ）は一のインシュレータタイプのダンパーの外観斜視図、分図（ｂ）は他のインシュレータタイプのダンパーの外観斜視図。
【図９】第２の従来例によるメカニカルシャーシの防振構造の説明図。
【図１０】図９の防振構造で用いるダンパーの説明図で、分図（ａ）は分図（ｂ）のＳＡ−ＳＡ線に沿うダンパーの断面図、分図（ｂ）はダンパーの平面図。
【符号の説明】
１外装部材
１ａ側板部
１ｂ底板部
２メカニカルシャーシ
３ディスク（ディスク状記録媒体）
１０メカニカルシャーシ
１０ａ側壁部
１０ｂ支持軸
１０ｃ上面
２１異方性ダンパー（第１実施形態）
２２周壁部材
２２ａ垂直部
２２ｂ水平部
２３可撓部材
２３ａ環状端末部
２３ｂ垂直部
２３ｃ水平部
２３ｋ頂部
２４蓋部材
３１異方性ダンパー（第２実施形態）
３２周壁部材
３２ａ垂直部
３２ｂ水平部
３３可撓部材
３３ａ環状端末部
３３ｂ垂直部
３３ｃ水平部
３３ｆ頂部
４１異方性ダンパー（第３実施形態）
４２可撓部材
４２ａ水平部
４２ｂ環状端末部
４２ｃ頂部
４２ｄ垂直部
４２ｅ段差部
ｘ横方向
ｙ縦方向（面直方向）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a damper in a vibration transmission path that attenuates vibration. More specifically, optical devices such as CDs, magneto-optical discs such as MOs, magnetic discs such as hard disks, etc. used for in-vehicle and consumer audio equipment, video equipment, information equipment, various precision equipment, etc. A damper that is suitable for attenuating disturbance vibration and disturbance vibration transmitted between a mechanical chassis on which a non-contact reading mechanism for various disk-shaped recording media is mounted and an exterior member surrounding the mechanical chassis; It relates to the vibration structure.
[0002]
[Prior art]
With respect to the disk-shaped recording medium (hereinafter simply referred to as “disk”) as described above, recorded data is read in a non-contact manner using an optical pickup or a magnetic head. Although such a non-contact reading mechanism is mounted on a mechanical chassis, various types of anti-vibration measures are taken for the above-described various devices including the mechanical chassis as an exterior member because the reading method is non-contact. As an example, there is known an example in which a damper is interposed between an exterior member and a mechanical chassis to elastically support the mechanical chassis in a floating state.
[0003]
FIG. 7 shows the first conventional example, in which 1 is an exterior member and 2 is a mechanical chassis. A disk 3 is mounted on the mechanical chassis 2, and data recorded on the disk 3 is read out by a non-contact reading mechanism mounted on the mechanical chassis 2. A damper 4 is attached between the mechanical chassis 2 and the exterior member 1. The damper 4 is of a cylindrical insulator type as shown in FIG. 8, and is formed of a rubber-like elastic body such as a styrene elastomer. An insertion hole 4 a is formed through the damper 4 along its axis, and the damper 4 is fixed to the exterior member 1 by screwing the screw N inserted therethrough into the exterior member 1. . Further, the damper 4 is formed with a small-diameter recess 4b, and the damper 4 is fixed to the mechanical chassis 2 by engaging the mounting portion 2a of the mechanical chassis 2 with the recess 4b. The first conventional example has a structure in which the mechanical chassis 2 is elastically anti-vibrated and supported in a floating state with respect to the exterior member 1 by using three such insulator type dampers 4.
[0004]
FIG. 9 shows a second conventional example. As shown in FIG. 10, the damper 5 in this conventional example includes a substantially cylindrical peripheral wall member 6 formed of a hard resin such as polypropylene, and a heat. A flexible member 7 that is formed of a rubber-like elastic body such as a plastic elastomer, closes one end side opening of the peripheral wall member 6, and is formed of a hard resin such as polypropylene, and the other end side opening of the peripheral wall member 6 And a viscous fluid 9 made of silicone oil or the like sealed in an internal space formed by these members and acting on vibration damping. An attachment recess 7a is formed in the flexible member 7 made of a rubber-like elastic body. The mechanical chassis 10 is held by inserting a support shaft 10b protruding from the side wall 10a into the attachment recess 7a. Thus, the structure is supported by the damper 5 and the coil spring S in an anti-vibration manner. The damper 5 is fixed to the exterior member 1 by inserting a screw N through an insertion hole 8 a formed in the lid member 8 and screwing the screw N into the screw hole of the exterior member 1. In the second conventional example, three such viscous fluid-filled dampers 5 are used to elastically support the exterior of the mechanical chassis 10 in a floating state with respect to the exterior member 1. Yes.
[0005]
[Problems to be solved by the invention]
By the way, notebook-type personal computers, portable electronic devices, and the like are particularly prone to thinning of the entire device, and there is a rapid demand for anti-vibration measures in a narrow internal space. The first conventional example and the second conventional example described above are for adapting to such anti-vibration measures in a narrow internal space, and can exhibit anti-vibration characteristics that meet the requirements. It has become. That is, in the first conventional example, since the insulator type damper 4 whose height can be set relatively low is used, it is possible to cope with the thinning of the exterior member 1 in the longitudinal direction y. Further, in the second conventional example, the lid member 8 of the damper 5 is fixed to the side plate portion 1a of the exterior member 1, and the damper 5 is attached sideways along the lateral direction x. Compared to the case where the member 1 is attached to the bottom plate 1b, the exterior member 1 can be made thinner in the longitudinal direction y.
[0006]
However, recently, there are many voices that require further thinning of the entire device, and it is difficult to exhibit satisfactory anti-vibration characteristics if the first and second conventional examples are applied as they are. It has become to. That is, in order to improve the damping effect in these conventional examples, a rubber-like elastic body (styrene elastomer) having a low hardness is used for the damper 4 of the first conventional example, and the damper 5 of the second conventional example. It is conceivable to reduce the hardness of the rubber-like elastic body (thermoplastic elastomer) forming the flexible member 7 or to lower the viscosity of the viscous fluid 9. However, in order to further reduce the thickness of the entire device, the gaps between the various components provided in the exterior member 1 are further narrowed, so that the buoyancy, disturbance vibration, and disturbance generated when the disk 3 rotates at a high speed. The disk 3 itself and the

mechanical chassis

2 and 10 are lifted in the longitudinal direction y by the vibration, and may be brought into contact with the inner surface of the exterior member 1 and various peripheral parts by receiving the vibration and floating in a floating state. There was a problem.
[0007]
In order to avoid this problem, for example, in the first conventional example, like the damper 12 shown in FIG. 8B, the upper and lower portions of the large diameter are formed by the highly elastic portion 12a, and the small diameter is formed. It is conceivable to form the intermediate portion of the lower elastic portion 12b. That is, the high elastic portion 12a performs vibration attenuation in the longitudinal direction y and the low elastic portion 12b performs vibration attenuation in the horizontal direction x. As a whole, the high elastic portion 12a performs the vertical vibration of the disk 3 and the mechanical chassis 2 in the vertical direction. The displacement is suppressed. However, there is a problem that the damping effect against external vibration is deteriorated due to the influence of the highly elastic portion 12a. With the insulator type dampers 4 and 12, the entire device can be further reduced in thickness without impairing the vibration isolation characteristics. I could not expect any other improvement measures to respond.
[0008]
Further, in the second conventional example, the above-mentioned contact problem can be solved by increasing the hardness of the rubber-like elastic body constituting the flexible member 7 and the viscosity of the viscous fluid 9. Similarly, the damping effect against external vibration is reduced.
[0009]
The present invention is based on the background of the conventional example and the improvement measures as described above, and the object of the present invention is to cope with further thinning of the entire device without impairing the vibration isolation characteristics. An object of the present invention is to provide an anti-vibration structure for a damper and a mechanical chassis.
[0010]
[Means for Solving the Problems]
  That is, a cylindrical peripheral wall member, a flexible member made of a rubber-like elastic body that is fixed to one end of the peripheral wall member and closes the one end side opening, and a second end fixed to the other end of the peripheral wall member and closes the other end side opening. A lid member;
And a viscous fluid enclosed in an internal space formed by a peripheral wall member, a flexible member, and a lid member, and either the lid member or the flexible member implements a non-contact type reading mechanism for a disk-shaped recording medium.It has a disk mounting surface on its upper surfaceMechanical chassisSide position ofA damper that is attached to an exterior member that surrounds the mechanical chassis at a lateral position of the mechanical chassis and that supports the mechanical chassis in a floating state with respect to the exterior member. The peripheral wall member is formed of a rectangular rectangular tube-shaped hard resin, and the flexible member has a vertical portion that is deflected in a substantially perpendicular direction of the mechanical chassis in the attached state, and a length longer than the vertical portion. A rectangular dome shape that has a horizontal portion that is deflected in a substantially plane direction, has a spring constant that is hard in the direction perpendicular to the plane, and a soft spring constant in the direction of the plane. The terminal portion is fixed to one end of the rectangular wall-shaped peripheral wall member, and the top of the rectangular dome-shaped flexible member protrudes toward the internal space filled with the viscous fluid, Or it has the axis | shaft holding | maintenance part which inserts and hold | maintains the pin-shaped support shaft which protrudes from an exterior member, and the vertical part and horizontal part of a flexible member hold | maintain a cyclic | annular terminal part and a pin-shaped support shaft. The vibration of the mechanical chassis is attenuated by elastic deformation in the substantially plane direction and the substantially plane direction having anisotropy in an axis crossing direction centering on the support shaft between the shaft holding portion and the shaft holding portion. An anisotropic damper.
[0011]
This anisotropic damper has a portion of the flexible member corresponding to the vertical direction so that it is substantially perpendicular to the surface of the mechanical chassis, and a portion corresponding to the horizontal direction that is substantially horizontal to the surface of the mechanical chassis. By softening the spring constant, a high damping effect is exhibited while suppressing relative displacement between the mechanical chassis and the exterior member caused by buoyancy, disturbance vibration, and disturbance vibration when the disk rotates at high speed.
[0012]
  That is, the rubber-like elastic body constituting the flexible member has a predetermined hardness that satisfies a desired vibration-proof characteristic,Reduce the vertical lengthThe spring constant is hardened, and the lateral direction (horizontal direction)Make the horizontal part longer than the vertical partThe spring constant is softened. Therefore, unlike the second conventional example, it is not necessary to increase the hardness of the flexible member in such a direction that the vibration damping effect is inevitably impaired, and in the case of a viscous fluid-filled damper, the viscosity of the viscous fluid is increased. Even if the hardness and viscosity are such that the desired vibration isolation characteristics can be exhibited, a high damping effect can be exhibited while suppressing the buoyancy acting on the disk and the mechanical chassis. The anisotropic damper according to the present invention is also applicable to a viscous fluid-filled damper, and also to an air damper that exhibits a vibration damping effect by providing air holes in the peripheral wall member and the like and air resistance flowing in and out of the air hole. can do.
[0013]
Moreover, this invention forms the thickness of the said horizontal part thicker than the thickness of a vertical part about the said anisotropic damper.
[0014]
Since the thickness of the horizontal portion is thicker than the thickness of the vertical portion, it is possible to increase the suppression of relative displacement in the longitudinal direction of the mechanical chassis and the exterior member, and to further suppress the displacement.
[0015]
  Furthermore, the present invention provides an annular damper that is fixed to the opening at one end of the peripheral wall member with respect to the anisotropic damper.TerminalThe horizontal portion is formed by making the thickness on the top side thinner than the thickness on the portion side.
[0016]
  The horizontal part has a uniform thickness and is annularTerminalSince the thickness on the top side is thinner than the thickness on the part side, the spring constant in the vertical direction is harder due to the thick annular end part side that is fixed to the peripheral wall member and has relatively little adverse effect on the damping performance Thus, the vertical relative displacement between the mechanical chassis and the exterior member can be suppressed. And about a horizontal direction, vibration damping performance can be improved with the thin top part side. Therefore, vibration damping performance and buoyancy suppression can be exhibited in a better balance than a flexible member having an equal thickness.
[0017]
In this case, even if the horizontal part of the flexible member is such that the wall thickness gradually changes from the annular terminal part side to the top part side, the wall thickness also changes with a surface difference at the step part. It may be what you did.
[0018]
  Further, the present invention that achieves the above object includes a cylindrical peripheral wall member, a flexible member made of a rubber-like elastic body that is fixed to one end of the peripheral wall member and closes the one end side opening, and the other end of the peripheral wall member. Either a lid member or a flexible member includes a lid member that adheres and closes the opening at the other end, and a peripheral wall member, a flexible member, and a viscous fluid sealed in an internal space formed by the lid member. A non-contact reading mechanism for disc-shaped recording mediaIt has a disk mounting surface on its upper surfaceMechanical chassisSide position ofA mechanical chassis in which one of the other is attached to an exterior member surrounding the mechanical chassis at a side position of the mechanical chassis, and the damper is supported by the damper in a floating state with respect to the exterior member. With respect to the vibration isolating structure, the peripheral wall member of the damper is made of a hard resin having a rectangular rectangular tube shape, and the flexible member of the damper is a vertical portion that is deflected in a substantially perpendicular direction of the mechanical chassis in the mounted state; It has a horizontal part that is longer than the vertical part and is deflected in the substantially plane direction of the mechanical chassis, and has a rectangular dome shape in which the spring constant is hard in the substantially perpendicular direction and the spring constant is soft in the substantially face direction. An annular terminal portion of the rectangular dome-shaped flexible member is fixed to one end of the rectangular wall-shaped peripheral wall member, and the top of the rectangular dome-shaped flexible member is filled with viscous fluid. Projecting toward the internal space, and having a shaft holding part for inserting and holding a pin-shaped support shaft projecting from the mechanical chassis or the exterior member, the vertical part and the horizontal part of the flexible member are Between the annular terminal portion and the shaft holding portion that holds the pin-shaped support shaft, by elastic deformation in the substantially perpendicular direction and the substantially planar direction having anisotropy in the axis crossing direction around the support shaft It is characterized by damping the vibration of the mechanical chassis.
[0019]
  According to the vibration isolating structure of the mechanical chassis, the flexible member of the damper has a rectangular dome shape having a short vertical portion and a long horizontal portion in the longitudinal direction, and the vertical portion is Since the horizontal portion is attached along the substantially surface direction of the mechanical chassis and the horizontal portion is attached along the substantially surface direction of the mechanical chassis, the rubber-like elastic body forming the flexible member satisfies a desired vibration-proof characteristic. While having a predetermined hardness, about the longitudinal directionReduce the vertical lengthThe spring constant is hardened, and the lateral direction (horizontal direction)Make the horizontal part longer than the vertical partThe spring constant is softened. Therefore, unlike the second conventional example, it is not necessary to increase the hardness of the flexible member in such a direction that the vibration damping effect is inevitably impaired, and in the case of a viscous fluid-filled damper, the viscosity of the viscous fluid is increased. Even if the hardness and viscosity are such that the desired vibration isolation characteristics can be exhibited, a high damping effect can be exhibited while suppressing the buoyancy acting on the disk and the mechanical chassis.
[0020]
In this case, as a specific mounting form of the damper, a side wall portion is provided in the mechanical chassis in the vertical direction (vertical direction), and a lid member that closes the other end side opening of the peripheral wall member of the damper is screwed to the side wall portion. The exterior member is fixed by a fixing means such as a stopper, and the support shaft is projected inwardly on the exterior member, and the support shaft is inserted and held in the mounting recess formed in the flexible member of the damper. A damper can be installed between the machine chassis and the mechanical chassis. On the contrary, the lid member of the damper is fixed to the inner surface of the side plate portion of the exterior member, and the support shaft protruding from the side wall portion of the mechanical chassis is inserted and held in the mounting recess of the flexible member of the damper. It is good also as the attachment structure of the made damper.
[0021]
Further, according to the present invention, in the damper in the vibration isolating structure of the mechanical chassis, the thickness of the horizontal portion is formed thicker than the thickness of the vertical portion.
[0022]
Since the thickness of the horizontal portion is thicker than the thickness of the vertical portion, it is possible to increase the suppression of relative displacement in the longitudinal direction of the mechanical chassis and the exterior member, and to further suppress the displacement.
[0023]
  Furthermore, the present invention relates to a damper in the vibration isolating structure for the mechanical chassis, and an annular shape that is fixed to an opening on one end side of the peripheral wall member.TerminalThe horizontal portion is formed by making the thickness on the top side thinner than the thickness on the portion side.
[0024]
  The horizontal part has a uniform thickness and is annularTerminalSince the thickness on the top side is thinner than the thickness on the part side, the spring constant in the vertical direction is harder due to the thick annular end part side that is fixed to the peripheral wall member and has relatively little adverse effect on the damping performance Thus, the vertical relative displacement between the mechanical chassis and the exterior member can be suppressed. And about a horizontal direction, vibration damping performance can be improved with the thin top part side. Therefore, vibration damping performance and buoyancy suppression can be exhibited in a better balance than a flexible member having an equal thickness.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, about the same member in each embodiment, the overlapping description is abbreviate | omitted using a common code | symbol.
[0026]
First Embodiment [FIGS. 1 to 3]
[0027]
The anisotropic damper 21 of this embodiment includes a cylindrical peripheral wall member 22, a flexible member 23, a lid member 24, and a viscous fluid 9 enclosed in an internal space formed by these members.
[0028]
As shown in the plan view of FIG. 1, the peripheral wall member 22 is formed in a substantially rectangular shape having a vertical portion 22a and a horizontal portion 22b. The vertical portion 22a is attached with its length direction aligned with the vertical direction y in a state of being attached to the exterior member 1, and the horizontal portion 22b is attached with its length direction aligned with the horizontal direction x.
[0029]
The material of the peripheral wall member 22 is preferably a rigid material. Depending on the required performance such as dimensional accuracy, heat resistance, mechanical strength, durability, and reliability of the target component, thermoplastic resin, thermosetting It is possible to select from resin, metal and the like. For example, thermoplastic resins include polyethylene resin, polypropylene resin, polyvinyl chloride resin, polystyrene resin, acrylonitrile / styrene / acrylate resin, acrylonitrile / butadiene / styrene resin, polyamide resin, polyacetal resin, polycarbonate resin, polyethylene A terephthalate resin, a polybutylene terephthalate resin, a polyphenylene oxide resin, a polyphenylene sulfide resin, a polyurethane resin, a polyphenylene ether resin, a modified polyphenylene ether resin, a silicone resin, a polyketone resin, a liquid crystal polymer, or a composite material thereof can be used. Moreover, as a thermosetting resin, a phenol resin, an epoxy resin, a silicone resin, a polyurethane resin, a melamine resin, an unsaturated polyester resin, etc., and those composite materials can be utilized. As the metal, stainless steel and various die casts can be used.
[0030]
The flexible member 23 in which the annular terminal portion 23a is fixed to the opening on the one end side of the peripheral wall member 22 as described above is formed in a rectangular dome shape like the peripheral wall member 22, and the thickness of each flexible member 23 is generally determined for each part. In the same thickness.
[0031]
The flexible member 23 includes a vertical portion 23b having a length d2 that is aligned with the perpendicular direction of the upper surface 10c of the mechanical chassis 10, that is, the vertical direction y, and the surface direction of the mechanical chassis 10, that is, the lateral direction x ( In FIG. 3, for convenience of explanation, the longitudinal direction of the exterior member 1 is shown as the horizontal direction x, but the horizontal direction x includes a direction perpendicular to the paper surface. Is formed.
[0032]
In each vertical portion 23b, bulged

curved portions

23e and 23f are formed with a bent portion 23d as a boundary. Since the flexible member 23 has a rectangular dome shape, the bending portion 23e is shorter in the length direction than the bending portion 23f. In addition, each horizontal portion 23c is formed with bulging

curved portions

23g and 23h with different lengths from the bent portion 23d. The vertical portion 23b and the horizontal portion 23c are continuous with bulged curved surfaces at four corners 23i where they intersect.
[0033]
And the top part 23k where the vertical part 23b and the horizontal part 23c converge is made into the flat part, The shaft holding part 23m which protrudes inward of the surrounding wall member 22 is formed in the center part. The mechanical chassis 10 is attached to the anisotropic damper 21 by the support shaft 10b of the side wall portion 10a being inserted and held in the attachment recess 23n of the shaft holding portion 23m.
[0034]
Here, the characteristics required as the material of the flexible member 23 will be described. A material having high durability and damping characteristics and low creep characteristics is preferable. Specifically, with respect to the durable physical properties, the rubber tensile physical properties are 2 MPa or more, preferably 4 MPa or more. For the damping characteristics, a high damping material having a loss coefficient tan δ of 0.05 or more (25 ° C.), preferably 0.2 or more is suitable. This is because if the loss coefficient tan δ is less than 0.05, the amplitude of the mechanical chassis 10 at the time of resonance increases, and there is a risk of contact with the exterior member 1. Further, regarding the creep characteristics, those having a low creep characteristic with a compression set (70 ° C. × 22 hours) of 50% or less, preferably 30% or less are suitable. This is because if the compression set (70 ° C. × 22 hours) is larger than 50%, the displacement amount of the mechanical chassis 10 after being left for a long time may increase and come into contact with the exterior member 1.
[0035]
The material of the flexible member 23 that requires the above characteristics depends on the required performance such as dimensional accuracy, heat resistance, mechanical strength, durability, reliability, anti-vibration characteristics, damping characteristics, etc. of the target part. And can be selected from thermoplastic elastomers, crosslinked rubbers and the like. For example, thermoplastic elastomers include styrene thermoplastic elastomers, olefin thermoplastic elastomers, polyester thermoplastic elastomers, polyurethane thermoplastic elastomers, polyamide thermoplastic elastomers, and vinyl chloride thermoplastic elastomers. Available. Cross-linked rubbers include natural rubber, butadiene rubber, isoprene rubber, styrene butadiene copolymer rubber, nitrile rubber, hydrogenated nitrile rubber, chloroprene rubber, ethylene propylene rubber, chlorinated polyethylene, chlorosulfonated polyethylene, butyl rubber and halogenated butyl rubber. Acrylic rubber, fluorine rubber, urethane rubber, silicone rubber, etc. can be used.
[0036]
The lid member 24 closes the opening on the other end side of the peripheral wall member 22 and is formed in a relative shape with the outward flange 22c of the peripheral wall member 22, and is fixed to the outward flange 22c by ultrasonic welding. Is done. The material is the same as that of the peripheral wall member 22.
[0037]
Next, the mounting structure of the anisotropic damper 21 will be described. As shown in FIG. 3, the anisotropic damper 21 is attached so that the vertical portion 23b of the flexible member 23 is aligned along the direction perpendicular to the upper surface 10c of the mechanical chassis 10, that is, the vertical direction y, and the horizontal portion 23c is attached to the mechanical chassis. It is attached along the surface direction of 10, that is, the lateral direction x. For the attachment, the lid member 24 is fixed to the side plate portion 1a of the exterior member 1 by adhesion. In addition, even if it is not adhesion | attachment, the cover member 24 is screwed with respect to the side-plate part 1a of the exterior member 1, or a claw-like engagement piece is provided in the lid member 24 or the surrounding wall member 22, and this is attached to the exterior member 1. It may be fixed by engaging, or conversely, a claw-like engagement piece may be provided on the exterior member 1 and this may be fixed by engaging with the lid member 24 or the peripheral wall member 22. In addition to such mechanical fixing means, it may be fixed by chemical fixing means such as fusion or welding. In addition, the support shaft 10 b of the mechanical chassis 10 is inserted and held in the mounting recess 23 n of the flexible member 23 of the anisotropic damper 21 so that the coil spring S surrounds the anisotropic damper 21. In this embodiment, since the mechanical chassis 10 is supported by the three anisotropic dampers 21 in an anti-vibration manner, the anisotropic work as shown in FIG. The attachment structure of the property damper 21 is obtained.
[0038]
Next, functions and effects of the anisotropic damper 21 according to the first embodiment and its mounting structure will be described.
[0039]
The flexible member 23 of the anisotropic damper 21 has a short length d2 in the longitudinal direction y so as to be perpendicular to the plane of the mechanical chassis 10.TheThe spring constant is hardened, and the length d1 is longer than the vertical portion 23b in the lateral direction x in the plane direction of the mechanical chassis 10.TheThe spring constant is softened. Therefore, the relative displacement between the exterior member 1 and the mechanical chassis 10 in the longitudinal direction y caused by internal vibration, disturbance vibration, buoyancy when the disk 3 rotates at high speed, or the like.IsControlled, ShakeMovementIs reducedTo be attenuated. Therefore, unlike the above-described conventional example, it is not necessary to increase the hardness of the flexible member 23 or increase the viscosity of the viscous fluid 9 with a direction that inevitably impairs the damping effect on vibration, and can exhibit desired vibration isolation characteristics. Even if the hardness and viscosity are maintained, a high damping effect can be exhibited while suppressing the relative displacement between the disk 3 and the mechanical chassis 10.
[0040]
Second Embodiment [FIGS. 4, 5, and 3]
[0041]
The anisotropic damper 31 of this embodiment differs in the structure of the surrounding wall member 32 and the flexible member 33 compared with the anisotropic damper 21 of 1st Embodiment. In addition, about the structure of the other anisotropic damper 31 and its attachment structure, it is the same as that of 1st Embodiment.
[0042]
In the peripheral wall member 32 constituting the anisotropic damper 31, the width (thickness) d3 of the vertical portion 32a is different from the width (thickness) d4 of the horizontal portion 32b. This corresponds to the shape of the annular terminal portion 33a of the flexible member 33 fixed to the open end 32c of the peripheral wall member 32. That is, in the flexible member 33 of this embodiment, the thickness d5 of the vertical portion 33b is generally equal (FIG. 5 (b)), but the mounting recess 33e of the shaft holding portion 33d is sandwiched in FIG. 4 (b). The hatched area surrounded by the two-dot chain line shown above and belowRThe thickness of the horizontal portion 33c corresponding to is thickest than the thickness d5 of the vertical portion 33b in the annular terminal portion 33a, and is a flat top portion having the same thickness as the thickness d5 of the vertical portion 33b. It is formed so as to gradually become thin over 33f (FIG. 5A). And in the boundary part (part of a dashed-two dotted line shown in FIG. 4) in the back surface of the flexible member 33 between the vertical part 33b and the horizontal part 33c, it becomes an inclined surface from the thick horizontal part 33c to the thin vertical part 33b. ing.
[0043]
As described above, the characteristic of the flexible member 33 of the anisotropic damper 31 of this embodiment is that the vertical portion 33b and the horizontal portion 33c have different thicknesses, and the horizontal portion 33c is further changed from the annular terminal portion 33a to the top portion 33f. It is that the thickness is changed over time. And the anisotropic damper 31 can exhibit the following effect | action and effect in addition to the effect | action and effect of the anisotropic damper 21 of 1st Embodiment by this structure. That is, the horizontal portion 33c is fixed to the peripheral wall member 32 and has a relatively small spring constant on the side of the thick annular end portion 33a, which has a relatively small influence on the vibration damping performance, and gradually decreases in thickness from the top portion 33f to the top portion 33f. The spring constant becomes softer on the mounting recess 33e side. Therefore, on the side of the annular terminal portion 33a of the horizontal portion 33c having a hard spring constant, the relative displacement in the longitudinal direction y of the exterior member 1 and the mechanical chassis 10 is further strong, and the displacement can be further reduced. Further, on the mounting recess 33e side of the horizontal portion 33c having a soft spring constant, deformation in the lateral direction x is flexible and high damping performance can be exhibited.
[0044]
Third Embodiment [FIG. 6]
[0045]
An anisotropic damper 41 of this embodiment is a modification of the anisotropic damper 31 of the second embodiment, except that the configuration of the horizontal portion 42a of the flexible member 42 is different from that, and the other configurations are the second. This is the same as the embodiment. That is, the flexible member 42 is formed such that the horizontal portion 42a has the same thickness from the annular terminal portion 42b to the top portion 42c and is thicker than the vertical portion 42d. Then, at the boundary portion (the broken line portion shown in FIG. 6A) between the horizontal portion 42a and the vertical portion 42d on the back surface of the flexible member 42, a stepped portion 42e is formed from the thick horizontal portion 42a to the thin vertical portion 42d. It has been formed.
[0046]
And according to the anisotropic damper 41 of this 3rd Embodiment, compared with the anisotropic damper 31 of 2nd Embodiment, the horizontal part 42a is thicker than the vertical part 42d, and its thickness Therefore, the suppression of the relative displacement in the longitudinal direction y between the exterior member 1 and the mechanical chassis 10 is further strengthened, and the displacement is further reduced.
[0047]
Next, examples will be described.
[0048]
[Example 1]
Example 1 corresponds to the anisotropic damper 21 of the first embodiment described above, and its mounting structure is as shown in FIG.
[0049]
Specifically, two colors of a polypropylene resin and a styrene-based thermoplastic elastomer were molded to produce a peripheral wall member (22) and a flexible member (23). And after injecting the viscous fluid (9) into it, the outward flange (22c) and the lid member (24) made of polypropylene resin are sealed by ultrasonic fusion, and the anisotropic damper (21) is sealed. Obtained.
[0050]
The annular terminal portion (23a) of the flexible member (23) was rectangular, and its longitudinal direction was 10 mm and its lateral direction was 6.5 mm. Moreover, the thickness of the flexible member (23) was set to be equal to 0.3 mm. Further, as the styrenic thermoplastic elastomer forming the flexible member (23), one having a hardness of 30 (JIS K6253 type A), a compression set of 30%, and a loss factor tan δ of 0.20 (25 ° C.) was used. The viscous fluid (9) has a rotational viscosity of 1.2 m.²/ S silicone grease was used.
[0051]
[Example 2]
Example 2 corresponds to the anisotropic damper 31 of the second embodiment described above, and its mounting structure is the same as FIG.
[0052]
In Example 2, the thickness of the vertical portion (33b) of the flexible member (33) is 0.3 mm, and the thickness of the horizontal portion (33c) is 0.6 mm at the thickest annular end portion (33a). An isotropic damper (31) was used. The horizontal portion (33c) was gradually thinned from the thickest annular terminal portion (33a) to the top portion (33f). Except for the thickness of the flexible member (33), the other configuration is the same as the anisotropic damper (21) of the first embodiment.
[0053]
[Example 3]
Example 3 corresponds to the anisotropic damper 31 of the second embodiment described above, and its mounting structure is the same as FIG.
[0054]
In Example 3, the thickness of the vertical part (33b) of the flexible member (33) is 0.3 mm, and the thickness of the horizontal part (33c) is 0.9 mm at the thickest annular terminal part (33a). An isotropic damper (31) was used. The horizontal portion (33c) was gradually thinned from the thickest annular terminal portion (33a) to the top portion (33f). Except for the thickness of the flexible member (33), the other configuration is the same as the anisotropic damper (21) of the first embodiment.
[0055]
[Comparative Example 1]
Comparative Example 1 corresponds to the damper 12 shown in FIG. 8B, and its mounting structure is as shown in FIG.
[0056]
The damper (12) of Comparative Example 1 has a high elasticity portion (12a) made of a styrene elastomer having a hardness of 90 (JIS K6253 type A) and a low elasticity portion (12b) made of a styrene elastomer having a hardness of 30 (JIS K6253 type A). Is produced by two-color molding.
[0057]
[Comparative Example 2]
Comparative Example 2 corresponds to the damper 5 shown in FIG. 10, and its mounting structure is as shown in FIG.
[0058]
The damper (5) of Comparative Example 2 is different from Example 1 in that the shape of the peripheral wall member (6) and the flexible member (7) and the thickness of the flexible member (7) are equal to 0.3 mm. Only the difference from the isotropic damper (21) is the rest of the configuration.
[0059]
An evaluation test was performed for each of the above Examples and Comparative Examples. The evaluation test method is a vibration test. The conditions are as follows. In each example, three anisotropic dampers (21, 31) were used, and the mechanical chassis (10) having a weight of 70 g was supported in a vibration-proof manner by the mounting structure shown in FIG. Further, in Comparative Example 1, the mechanical chassis (2) having a weight of 70 g was supported by vibration isolation using the mounting structure shown in FIG. 7 using three dampers (12). In Comparative Example 2, the mechanical chassis (10) having a weight of 70 g was supported by vibration isolation using the mounting structure shown in FIG. 9 using three dampers (5). The disk reproducing apparatuses of the respective examples and comparative examples each including the mechanical chassis (10, 2) in the exterior member 1 are fixed to the vibration table.
[0060]
A constant acceleration of 5 m / s in the vertical direction (vertical direction y) and the horizontal direction (horizontal direction x) of the vibration table.² Then, the amount of displacement of the mechanical chassis (10, 2) was measured at the resonance frequency by measuring the vibration transmissibility to the mechanical chassis (10, 2). The resonance magnification is the vibration input acceleration a from the vibration table at the resonance frequency.₁Vibration output acceleration a from the mechanical chassis (10, 2)₂Is measured and 20 Log (a₁/ A₂). Further, vibration leakage to the outside when the disk (3) was rotated at a high speed (9600 rpm) was measured by a G sensor. The results of this vibration test are shown in Table 1.
[0061]
[Table 1]

[0062]
When Examples 1 to 3 and Comparative Example 1 are compared, in Comparative Example 1, since the damper is of the insulator type, it is inferior to Examples 1 to 3 in all evaluations in vibration damping performance. I understand that. Moreover, although the displacement amount in the vertical direction is superior to that of the first embodiment, it cannot be exhibited with the necessary vibration damping performance.
[0063]
Example 1 to Example3Compared with Comparative Example 2, in Comparative Example 2, the same evaluation as in Examples 1 to 3 was obtained in the evaluation of vibration damping performance, but the amount of displacement in the vertical direction is clearly more than in Examples 1 to 3. It turns out that it is greatly inferior, and it is inferior also about the vibration leak to the outside.
[0064]
Therefore, according to the first to third embodiments, the vertical displacement of the mechanical chassis can be significantly suppressed without reducing the vibration damping performance, and the device can be made thinner.
[0065]
【The invention's effect】
According to the anisotropic damper of the present invention, the spring constant is provided by the vertical portion having a short length in the longitudinal direction while having a predetermined hardness that satisfies the desired vibration-proof characteristics of the rubber-like elastic body forming the flexible member. In the lateral direction (horizontal direction), the spring constant is softened by the horizontal portion having a length longer than that of the vertical portion. Therefore, even if the hardness and viscosity are such that the desired vibration-proof characteristics can be exhibited, a high damping effect can be exhibited while suppressing the displacement of the disk and the mechanical chassis, and various devices including the mechanical chassis can be used. It can cope with further thinning.
[0066]
According to the present invention in which the thickness of the horizontal portion is thicker than the thickness of the vertical portion, it is possible to increase the suppression of the relative displacement in the vertical direction between the mechanical chassis and the exterior member, and to further suppress the displacement. be able to.
[0067]
The horizontal part has a uniform thickness and is annularTerminalAccording to the present invention in which the thickness on the top side is thinner than the thickness on the part side, it is the longitudinal direction by the thick annular end part side that is fixed to the peripheral wall member and has relatively little adverse effect on the damping performance. The spring constant in is hardened, and the vertical relative displacement between the mechanical chassis and the exterior member can be suppressed. And about a horizontal direction, vibration damping performance can be improved with the thin top part side. Therefore, vibration damping performance and buoyancy suppression can be exhibited in a better balance than a flexible member having an equal thickness.
[Brief description of the drawings]
FIG. 1 is a front view of a damper according to a first embodiment.
2A and 2B are cross-sectional views of the damper shown in FIG. 1, in which a partial view (a) is a cross-sectional view taken along line SB-SB, and a partial view (b) is a cross-sectional view taken along line SC-SC.
FIG. 3 is an explanatory view of a vibration isolating structure for a mechanical chassis using the damper according to the first to third embodiments.
FIGS. 4A and 4B are explanatory views of a damper according to a second embodiment, in which FIG. 4A is a front view of a peripheral wall member, and FIG. 4B is a front view of a flexible member.
5A and 5B are cross-sectional views of the damper according to the second embodiment, in which a partial view (a) is a cross-sectional view of the damper along the SD-SD line in FIG. 4, and a partial view (b) is along the SE-SE line in FIG. Sectional drawing of a damper.
6A and 6B are explanatory views of a damper according to a third embodiment, in which a partial view (a) is a front view, and a partial view (b) is a cross-sectional view taken along line SF-SF in the partial view (a).
FIG. 7 is an explanatory diagram of a vibration isolating structure for a mechanical chassis according to a first conventional example.
8 is an external perspective view including a partial cross section of a damper used in the vibration isolating structure of FIG. 7. FIG. 8 (a) is an external perspective view of one insulator type damper, and FIG. 8 (b) is another insulator type. The external appearance perspective view of a damper.
FIG. 9 is an explanatory view of a vibration isolating structure for a mechanical chassis according to a second conventional example.
FIG. 10 is an explanatory view of a damper used in the vibration isolating structure of FIG. 9, wherein a partial diagram (a) is a sectional view of the damper along the line SA-SA in the partial diagram (b), and a partial diagram (b) is a plane of the damper. Figure.
[Explanation of symbols]
1 Exterior member
1a Side plate
1b Bottom plate
2 Mechanical chassis
3 discs (disc-shaped recording media)
10 Mechanical chassis
10a Side wall
10b Support shaft
10c top surface
21 Anisotropic damper (first embodiment)
22 Perimeter wall member
22a Vertical section
22b Horizontal part
23 Flexible member
23a Ring terminal
23b Vertical section
23c Horizontal part
23k top
24 Lid member
31 Anisotropic damper (second embodiment)
32 Perimeter wall member
32a Vertical section
32b Horizontal part
33 Flexible member
33a Ring terminal
33b Vertical section
33c Horizontal part
33f Top
41 Anisotropic Damper (Third Embodiment)
42 Flexible members
42a Horizontal part
42b ring terminal
42c top
42d vertical section
42e Stepped part
x Horizontal direction
y Longitudinal direction (straight direction)

Claims

A cylindrical peripheral wall member;
A flexible member made of a rubber-like elastic body that adheres to one end of the peripheral wall member and closes the opening on the one end side;
A lid member that is fixed to the other end of the peripheral wall member and closes the other end side opening;
A viscous fluid sealed in an internal space formed by a peripheral wall member, a flexible member, and a lid member;
Either the lid member or the flexible member is mounted to a side position of the mechanical chassis having a disk mounting surface mounted on the upper surface of the non-contact type reading mechanism for the disk-shaped recording medium,
Any one of the above is attached to an exterior member surrounding the mechanical chassis at a side position of the mechanical chassis,
In the damper that supports the mechanical chassis in a floating state with respect to the exterior member,
The peripheral wall member is made of a rectangular rectangular tube-shaped hard resin,
A flexible member,
A vertical portion that is deflected in a substantially plane direction of the mechanical chassis in the mounted state, and a horizontal portion that is longer than the vertical portion and is deflected in a substantially plane direction of the mechanical chassis. It has a rectangular dome shape with a hard spring constant and a soft spring constant in the substantially plane direction.
The annular terminal portion of the rectangular dome-shaped flexible member is fixed to one end of a rectangular wall-shaped peripheral wall member,
At the top of the flexible member having a rectangular dome shape, there is a shaft holding part that protrudes toward the internal space filled with the viscous fluid and holds a pin-shaped support shaft that protrudes from the mechanical chassis or the exterior member. Have
The vertical portion and the horizontal portion of the flexible member are substantially perpendicular to each other between the annular terminal portion and the shaft holding portion that holds the pin-shaped support shaft, and have anisotropy in the direction of the axis crossing around the support shaft. An anisotropic damper characterized in that the vibration of the mechanical chassis is damped by elastic deformation in the direction and the substantially plane direction.

The anisotropic damper according to claim 1, wherein the horizontal portion is thicker than the vertical portion.

3. The anisotropic damper according to claim 1, wherein the horizontal portion is formed such that a thickness on a top portion side is thinner than a thickness on an annular terminal portion side fixed to an opening on one end side of the peripheral wall member.

The anisotropic damper according to claim 3, wherein the horizontal portion is gradually thinned from the annular terminal portion side to the top portion side.

A cylindrical peripheral wall member;
A flexible member made of a rubber-like elastic body that is fixed to one end of the peripheral wall member and closes the opening on the one end side;
A lid member that is fixed to the other end of the peripheral wall member and closes the other end side opening;
A damper including a viscous fluid sealed in an internal space formed by a peripheral wall member, a flexible member, and a lid member;
Either a lid member or a flexible member is mounted on a side position of a mechanical chassis having a disk-mounting surface mounted on a non-contact type reading mechanism for a disk-shaped recording medium,
Any one of the above is attached to an exterior member surrounding the mechanical chassis at a side position of the mechanical chassis,
In the vibration isolating structure of the mechanical chassis that supports the mechanical chassis in a floating state with respect to the exterior member with the damper,
A peripheral wall member of the damper is made of a rectangular rectangular tube-shaped hard resin,
The damper flexible member is:
A vertical portion that is deflected in a substantially plane direction of the mechanical chassis in the mounted state, and a horizontal portion that is longer than the vertical portion and is deflected in a substantially plane direction of the mechanical chassis. It has a rectangular dome shape with a hard spring constant and a soft spring constant in the substantially plane direction.
The annular terminal portion of the rectangular dome-shaped flexible member is fixed to one end of a rectangular wall-shaped peripheral wall member,
At the top of the flexible member having a rectangular dome shape, there is a shaft holding part that protrudes toward the internal space filled with the viscous fluid and holds a pin-shaped support shaft that protrudes from the mechanical chassis or the exterior member. Have
The vertical portion and the horizontal portion of the flexible member are substantially perpendicular to each other between the annular terminal portion and the shaft holding portion that holds the pin-shaped support shaft, and have anisotropy in the direction of the axis crossing around the support shaft. A vibration-damping structure for a mechanical chassis, wherein the vibration of the mechanical chassis is damped by elastic deformation in the direction and the substantially plane direction.