JP4169168B2

JP4169168B2 - Friction damper

Info

Publication number: JP4169168B2
Application number: JP09238998A
Authority: JP
Inventors: 正光小島; 美照五十嵐
Original assignee: Oiles Corp
Current assignee: Oiles Corp
Priority date: 1998-03-20
Filing date: 1998-03-20
Publication date: 2008-10-22
Anticipated expiration: 2018-03-20
Also published as: JPH11270576A

Description

【０００１】
【発明の属する技術分野】
本発明は摩擦ダンパーに関する。
【０００２】
【従来の技術】
摩擦ダンパーは、一般に、軸状に延在する内側部材と、前記内側部材と同軸上で内側部材の外側に配設される筒状の外側部材と、前記外側部材の内側で内側部材の外側の環状空間において前記内側部材と一体に回転する第１の部分と、前記環状空間において前記外側部材と一体に回転する第２の部分と、前記第１の部分と第２の部分を押し付ける弾性手段などを備えている。
そして、第１の部分と第２の部分間に摩擦力を発生させ、摩擦ダンパーにトルクを生じさせるようにしたもので、このトルクの値は調整できるものの一定であり、内側部材と外側部材の相対的な回転変位に応じてトルクの値が変ることはない。
一方、摩擦ダンパーが使われる箇所によっては、前記内側部材と外側部材の相対的な回転変位に応じてトルクの値を変化させたい場合も生じる。
【０００３】
【発明が解決しようとする課題】
しかしながら、従来の摩擦ダンパーでは上述のようにトルクの値は一定であり、このような箇所に使用することができない問題があった。
本発明は前記事情に鑑み案出されたものであって、本発明の目的は、内側部材と外側部材の相対的な回転変位に応じてトルクの値を変化させることができる摩擦ダンパーを提供することにある。
【０００４】
【課題を解決するための手段】
前記目的を達成するため本発明の摩擦ダンパーは、軸状に延在する内側部材と、該内側部材と同軸上で該内側部材の外側に配設された筒状の外側部材とを備え、前記外側部材は、円筒部と、該円筒部の長手方向の一端に形成された半径方向内方に突出するフランジ部とを有し、該フランジ部の中心に貫通孔が形成されており、該貫通孔の内周に前記内側部材の一端が嵌合されており、前記内側部材の外周面と前記外側部材の前記円筒部の内周面との間に環状空間が画成されており、前記環状空間に、摩擦係合部、弾性手段、及び付勢力可変手段が配設されており、前記摩擦係合部は、前記内側部材と一体に回転する第１の部分と、前記外側部材と一体に回転し前記第１の部分に対して軸方向において接触可能に設けられた第２の部分とで構成されており、前記弾性手段は、前記摩擦係合部の前記第１の部分と前記摩擦係合部の前記第２の部分とを接触させ押え付ける方向に付勢するように構成されており、前記付勢力可変手段は、前記内側部材と一体に回転する環状の内側可変部材と、前記内側可変部材に対向するように配置され前記外側部材と一体に回転する環状の外側可変部材とを有し、前記内側可変部材の前記外側可変部材に対向する面と、前記外側可変部材の前記内側可変部材に対向する面とに、夫々にカム部が形成されており、それらカム部の各々は、２つの基部と、それら基部から突出するようにして周方向に等間隔に形成された２つの凸部と、各基部と各凸部とを接続する傾斜部とを備えており、前記外側可変部材の前記カム部の前記凸部は、前記内側可変部材の前記カム部の前記基部、前記傾斜部、及び前記凸部のいずれかと常時当接し、前記内側可変部材の前記カム部の前記凸部は、前記外側可変部材の前記カム部の前記基部、前記傾斜部、及び前記凸部のいずれかと常時当接しており、前記外側可変部材の前記カム部の前記基部は、該基部が対向する前記内側可変部材の前記カム部の前記凸部よりも長い周方向長さを有し、前記内側可変部材の前記カム部の前記基部は、該基部が対向する前記外側可変部材の前記カム部の前記凸部よりも長い周方向長さを有しており、以上の構成により、前記内側部材と前記外側部材との間の相対的な回転変位に応じて前記内側可変部材と前記外側可変部材との間の軸方向距離が変化して、前記弾性手段が収容されるスペースの軸方向長さが変化し、もって、前記弾性手段の付勢力が変化して、該摩擦ダンパーで生じるトルクが変化するようにしたことを特徴とする。
また、本発明は、前記内側部材の中心に、軸方向に延在する軸挿通用孔が貫通形成されていることを特徴とする。
また、本発明は、前記内側部材の軸方向の端部に、半径方向の外方に突出するフランジ部が形成され、前記摩擦係合部の前記第１の部分はこのフランジ部により構成されていることを特徴とする。
また、本発明は、前記環状空間には前記内側部材と一体に回転する摩擦板が軸方向に移動可能に配設され、前記摩擦係合部の前記第１の部分は前記摩擦板により構成されていることを特徴とする。
また、本発明は、前記摩擦係合部の前記第２の部分は前記外側部材の前記フランジ部により構成されていることを特徴とする。
また、本発明は、前記環状空間には前記外側部材と一体に回転する摩擦板が軸方向に移動可能に配設され、前記摩擦係合部の前記第２の部分は前記摩擦板により構成されていることを特徴とする。
また、本発明は、前記弾性手段が、前記環状空間で前記摩擦係合部と前記付勢力可変手段との間に配置されていることを特徴とする。
また、本発明は、前記付勢力可変手段が前記摩擦係合部から離れる方向への動きを規制する規制手段が設けられていることを特徴とする。
また、本発明は、前記内側部材が、回転する軸に該軸と一体回転可能に結合され、前記外側部材が前記軸を回転可能に支持する部材に回転不能に結合され、前記摩擦係合部の前記第２の部分は、前記外側部材と共に回転不能となることを特徴とする。
【０００５】
本発明によれば、内側部材と外側部材との間に相対的な回転変位が生じると、第１の部分と第２の部分を押え付ける弾性手段の付勢力が付勢力可変手段により変えられる。
【０００６】
【発明の実施の形態】
以下、本発明の実施の形態に係る摩擦ダンパーを車のアクセルペダルの枢軸に取り付けた場合について説明する。
まず、第１の実施の形態から説明すると、図１はアクセルペダル装置の平面図、図２は同側面図を示す。
アクセルペダル装置１２は、車体側に取着されるブラケット１４、ブラケット１４に揺動可能に設けられたアクセルペダル１６、アクセルペダル１６を上方に付勢するねじりスプリング１８、摩擦ダンパー２４などで構成されている。
本実施の形態に係るアクセルペダル装置１２は、従来と同様に踏み込み操作によりガソリンエンジンの場合にはスロットルを開閉し、ディーゼルエンジンの場合には燃料噴射装置を作動させるものであるが、従来のようにアクセルペダルとスロットルの間、または、アクセルペダルと燃料噴射装置の間を連結するケーブルを用いていない。すなわち、従来のケーブルが連結されていたスロットルや燃料噴射装置の箇所にアクチュエータが連結されており、アクセルペダル１６の揺動変位を、投光器２０Ａ、受光器２０Ｂ、外周にスリットが形成され枢軸２２と一体に回転する円板２０Ｃなどからなる角度センサ２０により検出し、角度センサ２０により検出した検出信号に基づきコントローラを介してアクチュエータを駆動し、これによりスロットルや燃料噴射装置を作動させるようにしている。
【０００７】
前記ブラケット１４は、ねじ１４０１により車体側に固定される底板部１４０２と、底板部１４０２の両側からそれぞれ起立し互いに対向する側板部１４０４を備えている。
前記両側板部１４０４間にわたって枢軸２２が挿通され回転可能に支持されている。
前記アクセルペダル１６は、ロッド１６０２と、ロッド１６０２の長手方向の一端に取着されたペダル部１６０４を備え、ロッド１６０２の他端は、一方の側板部１４０４の外側で前記枢軸２２の端部に溶接により固着されている。
【０００８】
前記両側板部１４０４の内側の枢軸２２部分に前記ねじりスプリング１８と摩擦ダンパー２４が配設されている。
前記ねじりスプリング１８は、一端が一方の側板部１４０４の切り欠き１４０８から側板部１４０４の外側に突出し前記ロッド１６０２の上面に係止しており、他端が他方の側板部１４０４の孔に係止し、中間のコイル部が両側板部１４０４の間の枢軸２２部分に巻装され、これによりアクセルペダル１６はペダル部１６０４が所定の上限位置に位置し、ペダル部１６０４が踏み込まれると前記上限位置へ復帰する方向への付勢力が生じるように構成されている。
【０００９】
図３（Ａ）は摩擦ダンパーの端面図、（Ｂ）はアクセルペダルを踏み込みコイルスプリングが圧縮された状態の摩擦ダンパーの断面正面図、（Ｃ）はアクセルペダルから足が離れている状態でコイルスプリングが圧縮されていない状態の摩擦ダンパーの断面正面図、（Ｄ）は摩擦ダンパーの端面図で、（Ｂ）、（Ｃ）は（Ｄ）のＥＥ線断面に相当している。また、図４は摩擦ダンパーを構成する部材の説明図で、上段に描かれた絵は各部材の正面図を、中段に描かれた絵は各部材の側面図を示している。
前記摩擦ダンパー２４は、これらの図３、図４に示すように、軸状に延在する内側部材２６と、内側部材２６と同軸上で内側部材２６の外側に配設される筒状の外側部材２８と、内側部材２６の半径方向の外側で外側部材２８の半径方向の内側の環状空間３０に配設された摩擦板３２と、摩擦板３２を軸方向に付勢するコイルスプリング（弾性手段）３４と、摩擦力によりトルクを生じさせる摩擦係合部３６と、コイルスプリング３４の付勢力を可変とする付勢力可変手段３８と、ワッシャ４０、止めキャップ４２（規制手段）などを備えている。
【００１０】
前記内側部材２６の中心には軸方向に延在する軸挿通用孔２６０２が貫通形成され、この孔２６０２の断面は枢軸２２と同一で円の一部を切り欠いた形状となっており、孔２６０２に枢軸２２が挿通されることで内側部材２６と枢軸２２が一体に回転するように構成されている。
前記内側部材２６の軸方向の一端には半径方向の外方に膨出するフランジ部２６０４が形成され、軸方向の他端には周方向に等間隔をおき半径方向の外方に突出する凸部２６０６が４つ形成されている。また、内側部材２６の外周部には周方向に等間隔をおき軸方向に延在する凹部２６０８が前記他端に開放状に４つ形成されている。
【００１１】
前記外側部材２８は円筒部２８０２と、円筒部２８０２の軸方向の端部に半径方向の内方に膨出形成されたフランジ部２８０４とを備えている。
前記円筒部２８０２の内周部には周方向に等間隔をおき軸方向に延在する凹部２８０６が円筒部２８０２の端部に開放状に４つ形成され、また、前記フランジ部２８０４の外端面には軸方向に突出する脚部２８０８が２つ形成されている。この脚部２８０８は、図１に示すように、側板部１４０４の孔に挿入され固定されるもので、これにより側板部１４０４に対して外側部材２８が回転不能に取着されることになる。
また、フランジ部２８０４の中心には孔が貫通形成され、この孔に内側部材２６が挿入され、フランジ部２６０４、２８０４どうしが当接した状態で、外側部材２８の円筒部２８０２の内側で内側部材２６が同軸上に延在することになり、前記環状空間３０が円筒部２８０２の内側で内側部材２６の外側に形成されることになる。
そして、外側部材２８が側板部１４０４に回転不能に取着されることで、図１に示すように、内側部材２６のフランジ部２６０４が、外側部材２８のフランジ部２８０４と側板部１４０４との間に位置し、これにより内側部材２６は軸方向に移動不能に、言い換えると、外側部材２８に対して軸方向に相対的に移動不能に配設されることになる。
【００１２】
前記環状空間３０に配設される摩擦板３２は、本実施の形態では、第１乃至第５の５種類の摩擦板３２０１、３２０２、３２０３，３２０４，３２０５が用いられている。
これらの第１乃至第５の摩擦板３２０１、３２０２、３２０３，３２０４，３２０５はそれぞれ環板状を呈しており、それらの中心孔に内側部材２６が挿通されてそれらの順に環状空間３０に配設され、第２の摩擦板３２０２と第４の摩擦板３２０４として同一の摩擦板が用いられている。
前記摩擦板のうち第１、第３、第５の摩擦板３２０１、３２０３，３２０５はそれらの中心孔の内周部に周方向に等間隔をおいて４つの凸部３２１０と該凸部３２１０間にそれぞれ凹部３２１１が形成され、これらの凸部３２１０は内側部材２６が挿通された状態で内側部材２６の凹部２６０８に係合し、第１、第３、第５の摩擦板３２０１、３２０３，３２０５は内側部材２６と一体的に回転する。なお、該凹部３２１１は第１、第３、第５の摩擦板を内側部材２６の外周に挿入するさい、該内側部材２６に形成された凸部２６０６を通過させるためのものである。
前記摩擦板のうち第２、第４の摩擦板３２０２、３２０４はそれらの外周に周方向に等間隔をおいて４つの凸部３２１２が形成され、これらの凸部３２１２は内側部材２６が挿通された状態で外側部材２８の凹部２８０６に係合し、第２、第４の摩擦板３２０２、３２０４は外側部材２８と一体的に回転するように結合されるが、本実施の形態では、外側部材２８が側板部１４０４に回転不能に取着されることから、第２、第４の摩擦板３２０２、３２０４も回転せず、外側部材２８と一体に静止することになる。
そして、後述するようにコイルスプリング３４によりこれらの摩擦板３２は、フランジ部２８０４とコイルスプリング３４の間で押え付けられた状態となり、内側部材２６が回転することで、フランジ部２８０４、第２、第４の摩擦板３２０２、３２０４に対して第１、第３、第５の摩擦板３２０１、３２０３，３２０５が回転することから、これら摩擦板３２間に摩擦力が生じ、摩擦ダンパー２４にトルクが発生する。本実施の形態では、フランジ部２６０４、２８０４や摩擦板３２により前記摩擦係合部３６が構成されている。
【００１３】
前記第１乃至第５の摩擦板３２０１、３２０２、３２０３，３２０４，３２０５は、例えば、熱可塑性樹脂組成物から形成され、前記熱可塑性樹脂組成物はベース樹脂とこのベース樹脂に添加される第１の添加剤と第２の添加剤から構成され、前記ベース樹脂は、ポリアセタール樹脂またはポリフェニレンサルファイド樹脂であり、前記第１の添加剤は、オレフィン系重合体、スチレン系重合体およびフッ素系重合体から選択される１種または２種以上であり前記第２の添加剤は、潤滑油、ワックス、脂肪酸、黒鉛、二硫化モリブデンおよびリン酸塩から選択される１種または２種以上である。
【００１４】
前記ポリアセタール樹脂としては、ポリアセタールホモポリマーの他、主鎖の大部分がオキシメチレン連鎖より成るポリアセタールコポリマーを使用することができる。
さらに、ポリアセタールを公知の方法で架橋またはグラフト共重合して変性させた樹脂も使用することができる。
具体的には、イー・アイ・デュポン社製ホモポリマー「デルリン（商品名）」、ポリプラスチックス社製コポリマー「ジュラコン（商品名）」が挙げられる。
前記ポリフェニレンサルファイド樹脂としては、架橋型、直鎖型いずれでもよく、具体的には、フィリップス社製「ライトン（商品名）」、トープレン社製「トープレンＰＰＳ（商品名）」、呉羽化学工業社製「フォートロン（商品名）」が挙げられる。
【００１５】
前記第１の添加剤は、前記ベース樹脂の摺動特性を向上させるために用いられる。
第１の添加剤として、オレフィン系重合体、スチレン系重合体およびフッ素系重合体から選択される１種又は２種以上が添加される。
オレフィン系重合体としては、ポリエチレン、ポリプロピレン等の単独重合体およびこれらを主成分とする共重合体が挙げられる。
共重合体としては、エチレン−αオレフィン共重合体、エチレン−プロピレン−ジエン共重合体、エチレン−ビニルアセテート共重合体、エチレン−エチルアクリレート共重合体、エチレン−グリシジルメタクリレート共重合体、エチレン−エチルアクリレート−無水マレイン酸共重合体等が挙げられる。
さらに、前記単独重合体および共重合体にポリスチレン、ポリメチルメタクリレート、アクリロニトリル−スチレン共重合体をグラフトした共重合体も含まれる。
上記オレフィン系重合体は、単独でまたは２種以上の混合物若しくは反応生成物の形で使用される。
本発明で使用するスチレン系重合体とは、ポリスチレン−ゴム中間ブロック−ポリスチレン構造を持つトリブロック共重合体またはラジアルブロック共重合体である。
ゴム中間ブロックとしては、ポリブタジエン、ポリイソプレンおよびこれらを水素添加したものが挙げられる。
上記ブロック共重合体として具体的には、ポリスチレン−ポリブタジエン−ポリスチレンブロック共重合体、ポリスチレン−ポリイソプレン−ポリスチレンブロック共重合体、ポリスチレン−ポリ（エチレン・ブチレン）−ポリスチレンブロック共重合体およびポリスチレン−ポリ（エチレン・プロピレン）−ポリスチレンブロック共重合体が挙げられる。
さらに、本発明では、上記ブロック共重合体に官能基を導入したものも使用できる。
導入される官能基としては、マレイン酸、エンドシス−ジシクロ［２，２，１］ヘプト−５−エン−２，３−ジカルボン酸（ナジック酸）、無水マレイン酸、無水シトラコン酸、無水イタコン酸、無水テトラヒドロフタル酸、無水ナジック酸、無水メチルナジック酸、マレイン酸モノメチル、マレイン酸ジメチル、イタコン酸ジメチル、シトラコン酸ジメチル、マレイミド、塩化マレニルのグラフトモノマー等が挙げられ、特にマレイン酸、ナジック酸またはこれらの酸無水物が好ましい。
フッ素系重合体としては、ポリテトラフルオロエチレン、テトラフルオロエチレン−パーフルオロアルキルビニルエーテル共重合体、テトラフルオロエチレン−ヘキサフルオロプロピレン共重合体、テトラフルオロエチレン−エチレン共重合体、ポリクロロトリフルオロエチレン、クロロトリフルオロエチレン−エチレン共重合体、ポリビニリデンフルオライド、ポリビニルフルオライド等が挙げられる。
第１の添加剤の配合量は、オレフィン系重合体については０．３〜１０重量％、好ましくは０．５〜７重量％、スチレン系重合体については０．１〜１０重量％、好ましくは０．３〜６重量％、フッ素系重合体については２〜５０重量％、好ましくは２〜４０重量％である。
【００１６】
前記第２の添加剤は、さらに摺動特性を向上させるために第１の添加剤に加えて用いられる。
第２の添加剤として、潤滑油、ワックス、脂肪酸、黒鉛、二硫化モリブデンおよびリン酸塩から選択される１種または２種以上が添加される。
潤滑油としては、エンジン油、スピンドル油、タービン油、マシン油、シリンダー油、ギア油などの鉱油、ヒマシ油などの植物油、鯨油などの動物油、シリコーン油などの合成油が挙げられる。
ワックスとしては、パラフィンワックスの他、高級脂肪酸から誘導される脂肪酸エステル、脂肪酸アミド、脂肪酸塩などが挙げられる。
リン酸塩としては、アルカリ金属もしくはアルカリ土類金属の第三リン酸塩、第二リン酸塩、ピロリン酸塩、亜リン酸塩、メタリン酸塩が挙げられる。具体的には、第三リン酸リチウム（Ｌｉ₃ＰＯ₄）、第二リン酸リチウム（Ｌｉ₂ＨＰＯ₄）、ピロリン酸リチウム（Ｌｉ₄Ｐ₂Ｏ₇）、第三リン酸カルシウム（Ｃａ₃（ＰＯ₄）₂）、第二リン酸カルシウム（ＣａＨＰＯ₄あるいはＣａＨＰＯ₄・２Ｈ₂Ｏ）およびピロリン酸カルシウム（Ｃａ₂Ｐ₂Ｏ₇）が挙げられる。
第２の添加剤の配合量は、０．１〜１０重量％、好ましくは０．３〜６重量％である。
【００１７】
また、熱可塑性樹脂組成物の補強を目的として第３の添加剤を用いるようにしてもよい。
第３の添加剤として、ガラス粉末、炭素粉末（黒鉛は除く）、ガラス繊維、炭素繊維、アラミド繊維、チタン酸カリウムウィスカ、金属繊維、および金属粉末などから選択される１種または２種以上が１０重量％以下の割合で配合される。
【００１８】
上述のような第１乃至第５の摩擦板３２０１、３２０２、３２０３，３２０４，３２０５がそれらの順に環状空間３０に配設されたのち、第５の摩擦板３２０５に臨ませて前記コイルスプリング３４が配設され、続いてワッシャ４０、付勢力可変手段３８が配設され、最後に止めキャップ４２が配設される。
前記コイルスプリング３４は所望のヒステリシス特性が得られるように材料、線径、巻径、巻き数が決定されている。
前記ワッシャ４０は初期トルク設定用のもので、本実施の形態では３枚用いられている。
【００１９】
前記付勢力可変手段３８は、互いに対向する第１と第２の可変板３８Ａ、３８Ｂからなり、共に環板状に形成されている。
前記第１の可変板（外側可変部材）３８Ａの外周には半径方向の外方に突出する凸部３８１０が周方向に等間隔をおいて４つ形成され、これらの凸部３８１０は外側部材２８の凹部２８０６に係合し、第１の可変板３８Ａは外側部材２８と一体的に回転するように結合されるが、本実施の形態では、外側部材２８が側板部１４０４に回転不能に取着されることから、第１の可変板３８Ａも回転せず、外側部材２８と一体に静止することになる。
前記第２の可変板３８Ｂ（内側可変部材）の内周には半径方向の内方に突出する凸部３８１２が周方向に等間隔をおいて４つ形成され、これらの凸部３８１２は内側部材２６の凹部２６０８に係合し、第２の可変板３８Ｂは内側部材２６と一体的に回転する。
【００２０】
また、図５に示すように、第１と第２の可変板３８Ａ、３８Ｂが互いに向かい合う面の外周には、互いに係合可能なカム部３８２２，３８２４が形成され、各カム部３８２２、３８２４は、２つの基部３８３２と、それら基部３８３２から突出するようにして周方向に等間隔に形成された２つの凸部３８３４と、各基部３８３２と各凸部３８３４とを接続する傾斜部３８３６を備えている。そして、可変板３８Ａのカム部３８２２の基部３８３２は、該基部３８３２が対向する可変板３８Ｂのカム部３８２４の凸部３８３４よりも長い周方向長さを有し、可変板３８Ｂのカム部３８２４の基部３８３２は、該基部３８３２が対向する可変板３８Ａのカム部３８２２の凸部３８３４よりも長い周方向長さを有している。前記止めキャップ４２は環板状に形成され、その内周に半径方向の内方に突出する凹部４２０２が周方向に等間隔をおいて４つ形成され、これらの凹部４２０２は内側部材２６の凸部２６０６に係合し、止めキャップ４２は内側部材２６と一体的に回転する。
【００２１】
また、止めキャップ４２の端面には、軸方向に突出する凸部４２０４が周方向に等間隔をおいて二つ形成されている。この凸部４２０４は止めキャップ４２を着脱する際の操作を容易にするためのものである。
そして、環状空間３０に第１乃至第５の摩擦板３２０１、３２０２、３２０３，３２０４，３２０５、コイルスプリング３４、ワッシャ４０、第１の可変板３８Ａ、第２の可変板３８Ｂがそれらの順に環状空間３０に配設されたのち、止めキャップ４２が配設され、図１に示すように、スナップリング４２１０を用いて内側部材２６に抜落不能に取着される。
なお、止めキャップ４２を内側部材２６に抜落不能に取着する構造は、例えば、図６に示すように、止めキャップ４２の内周に雌ねじを形成しておき、内側部材２６の先端に雄ねじを形成しておき、雌ねじと雄ねじのねじ結合４２２０を用いてもよい。
【００２２】
本実施の形態では、アクセルペダル１６から足を離した状態でペダル部１６０４が上限位置にあり、摩擦ダンパー２４は図３（Ｃ）の状態となる。すなわち、第１の可変板３８Ａのカム部３８２２の凸部３８３４が、第２の可変板３８Ｂのカム部３８２４の基部３８３２に当接すると共に、第２の可変板３８Ｂのカム部３８２４の凸部３８３４が、第１の可変板３８Ａのカム部３８２２の基部３８３２に当接し、第１の可変板３８Ａと第２の可変板３８Ｂ間の軸方向寸法が最小で、環状空間３０内においてコイルスプリング３４が収容されるスペースの軸方向寸法が最大となっている。そして、アクセルペダル１６が踏み込まれるとこの状態から枢軸２２が回転し始め、内側部材２６が回転し始めるが、この時に摩擦板３２間で生じる初期トルクは、ワッシャ４０の枚数を変えることで、あるいは、厚さの異なるワッシャ４０に変えることで簡単に調整される。
【００２３】
次に、アクセルペダル１６を踏み込むと、コイルスプリング１８の弾発力で生じるトルクと、摩擦ダンパー２４で生じるトルクを加えた値のトルクが、足に負荷として掛かる。この場合、第１の可変板３８Ａのカム部３８２２の凸部３８３４が、第２の可変板３８Ｂのカム部３８２４の基部３８３２に当接し、第２の可変板３８Ｂのカム部３８２４の凸部３８３４が、第１の可変板３８Ａのカム部３８２２の基部３８３２に当接している間は、摩擦ダンパー２４で生じるトルクは一定である。
【００２４】
アクセルペダル１６が更に踏み込まれ、第１の可変板３８Ａのカム部３８２２の凸部３８３４が、第２の可変板３８Ｂのカム部３８２４の傾斜部３８３６に当接し、第２の可変板３８Ｂのカム部３８２４の凸部３８３４が、第１の可変板３８Ａのカム部３８２２の傾斜部３８３６に当接すると、アクセルペダル１６の踏み込み量に追従して第１の可変板３８Ａと第２の可変板３８Ｂ間の軸方向寸法が大きくなっていき、コイルスプリング３４が圧縮され、摩擦板３２間を押さえ付ける力が大きくなることから、摩擦ダンパー２４で生じるトルクが次第に大きくなっていく。そして、コイルスプリング１８の弾発力で生じるトルクと、摩擦ダンパー２４で生じる次第に大きくなるトルクを加えた値のトルクが、足に負荷として掛かる。
【００２５】
アクセルペダル１６が更に踏み込まれペダル部１６０４が下限位置になると、図３（Ｂ）に示すように、第１の可変板３８Ａのカム部３８２２の凸部３８３４が、第２の可変板３８Ｂのカム部３８２４の凸部３８３４に当接し、第２の可変板３８Ｂのカム部３８２４の凸部３８３４が、第１の可変板３８Ａのカム部３８２２の凸部３８３４に当接し、第１の可変板３８Ａと第２の可変板３８Ｂ間の軸方向寸法が最大となり、環状空間３０内においてコイルスプリング３４が収容されるスペースの軸方向寸法が最小となる。これによりコイルスプリング３４の圧縮量が最大となり、摩擦板３２間を押さえ付ける力が最大となることから、摩擦ダンパー２４で生じるトルクが最大になる。そして、コイルスプリング１８の弾発力で生じるトルクと、摩擦ダンパー２４で生じる最大のトルクを加えた値のトルクが、ペダル部１６０４の下限位置において足に負荷として掛かる。尚、以上の説明から明らかなように、可変板３８Ａのカム部３８２２の凸部３８３４は、可変板３８Ｂのカム部３８２４の基部３８３２、傾斜部３８３６、及び凸部３８３４のいずれかと常時当接しており、可変板３８Ｂのカム部３８２４の凸部３８３４は、可変板３８Ａのカム部３８２２の基部３８３２、傾斜部３８３６、及び凸部３８３４のいずれかと常時当接している。
【００２６】
このように本実施の形態では、アクセルペダル１６を踏み込むと、コイルスプリング１８の弾発力で生じるトルクと、摩擦ダンパー２４で生じるトルクを加えた値のトルクが、足に負荷として掛かる。そして、摩擦ダンパー２４の初期トルクは、ワッシャ４０の枚数を変えることで、あるいは、厚さの異なるワッシャ４０に変えることで簡単に調整することができる。また、摩擦ダンパー２４で生じるトルクは、コイルスプリング３４の材料、線径、巻径、巻き数や、摩擦板３２の材料を適宜選択することで所望の値に簡単に調整できる。さらに、摩擦ダンパー２４で生じるトルクを増大あるいは減少させるタイミングや、増大あるいは減少させる割合も、カム部３８２２、３８２４の形状を変えることで所望の値に簡単に調整できる。これらのことから、足に掛かる負荷、すなわち、コイルスプリング１８の弾発力で生じるトルクと、摩擦ダンパー２４で生じるトルクを加えた値のトルク、すなわち、ヒステリシス特性を簡単に所望値に設定することが可能となる。
【００２７】
したがって、本実施の形態によれば、従来のようにアクセルペダルとスロットルの間、または、アクセルペダルと燃料噴射装置の間を連結するケーブルを省いても、ケーブルを用いた場合と同じ負荷を簡単に足に与えることが可能となり、角度センサ、コントローラ、アクチュエータを用いてアクセルペダル装置１２を構成することが可能となる。
そして、ケーブルを省くことから、アクセルペダル１６回り、特にブラケット１４回りをコンパクト化することが可能となる。
【００２８】
次に、第１の実施の形態と同様に車のアクセルペダル装置に適用した第２の実施の形態に係る摩擦ダンパーについて説明する。
図７（Ａ）は摩擦ダンパーの端面図、（Ｂ）はアクセルペダルから足が離れている状態でコイルスプリングが圧縮されていない状態の摩擦ダンパーの断面正面図、（Ｃ）は摩擦ダンパーの端面図で、（Ｂ）は（Ｃ）のＤＤ線断面に相当している。また、図８は摩擦ダンパーを構成する部材の説明図で、上段に描かれた絵は各部材の正面図を、中段に描かれた絵は各部材の側面図を示している。
第２の実施の形態に係る摩擦ダンパー５２は、第１の実施の形態と同様に、図１、図２に示すアクセルペダル装置に用いられるものであり、摩擦ダンパー５２は、軸状に延在する内側部材５４と、内側部材５４と同軸上で内側部材５４の外側に配設される筒状の外側部材５６と、内側部材５４の半径方向の外側で外側部材５６の半径方向の内側の環状空間５８に設けられた摩擦係合部６０と、摩擦係合部６０を押し付けるコイルスプリング（弾性手段）６２と、コイルスプリング６２の押し付け力を可変とする付勢力可変手段６４、ワッシャ６６、止めキャップ６８などを備えている。
【００２９】
前記内側部材５４の中心には軸方向に延在する軸挿通用孔５４０２が貫通形成され、この孔５４０２の断面は、前記第１の実施の形態と同様に、枢軸２２の断面と同一で、孔５４０２に枢軸２２が挿通されることで内側部材５４と枢軸２２が一体に回転するように構成されている。
前記内側部材５４の軸方向の一端には半径方向の外方に膨出するフランジ部５４０４が形成され、また、内側部材５４の軸方向の他端には雄ねじ５４０６が形成されている。
【００３０】
前記外側部材５６は円筒部５６０２と、円筒部５６０２の軸方向の端部に半径方向の内方に膨出形成されたフランジ部５６０４とを備え、本実施の形態では、このフランジ部５６０４と内側部材５４のフランジ部５４０４とにより前記摩擦係合部６０が構成されている。
前記円筒部５６０２の内周部には周方向に等間隔をおき軸方向に延在する凹部５６０６が円筒部５６０２の端部に開放状に４つ形成され、また、前記フランジ部５６０４の外端面には、前記第１の実施の形態と同様に、側板部１４０４の孔に挿入され固定される脚部５６０８が２つ形成されている。
また、フランジ部５６０４の中心には孔が貫通形成され、この孔に内側部材５４が挿入され、フランジ部５４０４、５６０４どうしが当接した状態で、外側部材５６の円筒部５６０２の内側で内側部材５４が同軸上に延在することになり、前記環状空間５８が円筒部５６０２の内側で内側部材５４の外側に形成されることになる。
【００３１】
そして、フランジ部５６０４の中心の孔から突出する内側部材５４の先部に止め輪５７が取着され、この止め輪５７とフランジ部５４０４により外側部材５６のフランジ部５６０４が挟まれることになり、これにより内側部材５４は軸方向に移動不能に、言い換えると、外側部材５６に対して軸方向に相対的に移動不能に配設されることになる。
なお、第２の実施の形態では、第１の実施の形態のように、内側部材５４や外側部材５６と別体の摩擦板を用いておらず、フランジ部５４０４、５６０４が第１の実施の形態の摩擦板に相当し、後述するようにコイルスプリング６２によりこれらのフランジ部５４０４、５６０４は押え付けられた状態となり、内側部材５４が回転することで、フランジ部５６０４に対してフランジ部５４０４が回転することから、これらフランジ部５４０４、５６０４間に摩擦力が生じ、摩擦ダンパー５２にトルクを生じる。なお、フランジ部５４０４、５６０４の材料は第１の実施の形態の摩擦板と同一のものを使用可能である。
【００３２】
上述のように内側部材５４と外側部材５６が組み付けられた後、環状空間５８に前記コイルスプリング６２が配設され、続いてワッシャ６６、止めキャップ６８が配設される。
前記コイルスプリング６２は所望のヒステリシス特性が得られるように材料、線径、巻径、巻き数が決定されている。
前記ワッシャ６６は初期トルク設定用のもので、本実施の形態では３枚用いられている。
【００３３】
前記止めキャップ６８は筒状に形成され、その内周に雌ねじ６８０２が形成され、外周部には半径方向の外方に突出する凸部６８０４が周方向に等間隔をおいて４つ形成され、これらの凸部６８０４は外側部材５６の凹部５６０６に係合し、止めキャップ６８は外側部材５６と一体的に回転するように結合されるが、第１の実施の形態と同様に、外側部材５６が側板部１４０４に回転不能に取着されることから、止めキャップ６８も回転せず、外側部材５６と一体に静止することになる。
また、止めキャップ６８の端面には、軸方向に突出する凸部６８０６が周方向に等間隔をおいて二つ形成されている。この凸部６８０６は止めキャップ６８を着脱する際の操作を容易にするためのものである。
そして、内側部材５４と外側部材５６が組み付けられた後、環状空間５８にコイルスプリング６２、ワッシャ６６を配設した後、雄ねじ５４０６と雌ねじ６８０２の結合により止めキャップ６８を配設することで、環状空間５８からのコイルスプリング６２、ワッシャ６６の抜落が不能となる。
【００３４】
本実施の形態では、アクセルペダル１６から足を離した状態でペダル部１６０４が上限位置にあり、摩擦ダンパー５２は図７（Ｂ）の状態となる。
すなわち、外側部材５６のフランジ部５６０４と止めキャップ６８間の軸方向寸法が最大となっており、この状態で外側部材５６のフランジ部５６０４と内側部材５４のフランジ部５４０４はコイルスプリング６２により当接している。
そして、アクセルペダル１６が踏み込まれるとこの状態から枢軸２２が回転し始め、内側部材５４が回転し始めるが、この時にフランジ部５４０４、５６０４間で生じる初期トルクは、ワッシャ６６の枚数を変えることで、あるいは、厚さの異なるワッシャ６６に変えることで簡単に調整される。
【００３５】
次に、アクセルペダル１６を踏み込むと、コイルスプリング１８の弾発力で生じるトルクと、摩擦ダンパー５２で生じるトルクを加えた値のトルクが、足に負荷として掛かる。
この場合、アクセルペダル１６を踏み込みにより枢軸２２、内側部材５４が回転すると、止めキャップ６８は雄ねじ５４０６と雌ねじ６８０２により内側部材５４に結合され、同時に、凸部６８０４と凹部５６０６の係合により外側部材５６に回転不能に結合されているので、アクセルペダル１６の踏み込みに追従して止めキャップ６８は外側部材５６のフランジ部５６０４に近づく方向に移動する。これにより外側部材５６のフランジ部５６０４と止めキャップ６８間の軸方向寸法が小さくなっていき、コイルスプリング６２が圧縮され、フランジ部５４０４、５６０４間を押さえ付ける力が大きくなることから、摩擦ダンパー５２で生じるトルクが次第に大きくなっていく。なお、本実施の形態では、止めキャップ６８、ねねじ５４０６、雄ねじ６８０２、凸部６８０４、凹部５６０６により前記付勢力可変手段６４が構成されている。
そして、コイルスプリング１８の弾発力で生じるトルクと、摩擦ダンパー５２で生じる次第に大きくなるトルクを加えた値のトルクが、足に負荷として掛かることになる。
【００３６】
このように第２の実施の形態によっても、アクセルペダル１６を踏み込むと、コイルスプリング１８の弾発力で生じるトルクと、摩擦ダンパー５２で生じるトルクを加えた値のトルクが、足に負荷として掛かる。
そして、摩擦ダンパー５２の初期トルクは、ワッシャ６６の枚数を変えることで、あるいは、厚さの異なるワッシャ４０に変えることで簡単に調整することができる。
また、摩擦ダンパー５２で生じるトルクは、コイルスプリング６２の材料、線径、巻径、巻き数や、フランジ部５４０４、５６０４の材料を適宜選択することで所望の値に簡単に調整できる。
さらに、内側部材５４の回転変位に応じて摩擦ダンパー５２で生じるトルクが増大する割合も雄ねじ５４０６と雌ねじ６８０２のピッチを変えることで所望の割合に簡単に調整できる。
これらのことから、足に掛かる負荷、すなわち、コイルスプリング１８の弾発力で生じるトルクと、摩擦ダンパー５２で生じるトルクを加えた値のトルク、すなわち、ヒステリシス特性を簡単に所望値に設定することが可能となる。
【００３７】
したがって、第２の実施の形態によっても、従来のようにアクセルペダルとスロットルの間、または、アクセルペダルと燃料噴射装置の間を連結するケーブルを省いても、ケーブルを用いた場合と同じ負荷を簡単に足に与えることが可能となり、角度センサ、コントローラ、アクチュエータを用いてアクセルペダル装置１２を構成することが可能となり、ケーブルを省くことから、アクセルペダル１６回り、特にブラケット１４回りをコンパクト化することが可能となる。
なお、第１、第２の実施の形態では共に摩擦ダンパーをアクセルペダル装置に適用した場合について説明したが、本発明の摩擦ダンパーはアクセルペダル装置に限定されず、内側部材と外側部材の相対的な回転変位に応じてトルクの値を変化させたいような場合に全て適用される。
【００３８】
【発明の効果】
以上説明したように本発明の摩擦ダンパーは、軸状に延在する内側部材と、該内側部材と同軸上で該内側部材の外側に配設された筒状の外側部材とを備え、前記外側部材は、円筒部と、該円筒部の長手方向の一端に形成された半径方向内方に突出するフランジ部とを有し、該フランジ部の中心に貫通孔が形成されており、該貫通孔の内周に前記内側部材の一端が嵌合されており、前記内側部材の外周面と前記外側部材の前記円筒部の内周面との間に環状空間が画成されており、前記環状空間に、摩擦係合部、弾性手段、及び付勢力可変手段が配設されており、前記摩擦係合部は、前記内側部材と一体に回転する第１の部分と、前記外側部材と一体に回転し前記第１の部分に対して軸方向において接触可能に設けられた第２の部分とで構成されており、前記弾性手段は、前記摩擦係合部の前記第１の部分と前記摩擦係合部の前記第２の部分とを接触させ押え付ける方向に付勢するように構成されており、前記付勢力可変手段は、前記内側部材と一体に回転する環状の内側可変部材と、前記内側可変部材に対向するように配置され前記外側部材と一体に回転する環状の外側可変部材とを有し、前記内側可変部材の前記外側可変部材に対向する面と、前記外側可変部材の前記内側可変部材に対向する面とに、夫々にカム部が形成されており、それらカム部の各々は、２つの基部と、それら基部から突出するようにして周方向に等間隔に形成された２つの凸部と、各基部と各凸部とを接続する傾斜部とを備えており、前記外側可変部材の前記カム部の前記凸部は、前記内側可変部材の前記カム部の前記基部、前記傾斜部、及び前記凸部のいずれかと常時当接し、前記内側可変部材の前記カム部の前記凸部は、前記外側可変部材の前記カム部の前記基部、前記傾斜部、及び前記凸部のいずれかと常時当接しており、前記外側可変部材の前記カム部の前記基部は、該基部が対向する前記内側可変部材の前記カム部の前記凸部よりも長い周方向長さを有し、前記内側可変部材の前記カム部の前記基部は、該基部が対向する前記外側可変部材の前記カム部の前記凸部よりも長い周方向長さを有しており、以上の構成により、前記内側部材と前記外側部材との間の相対的な回転変位に応じて前記内側可変部材と前記外側可変部材との間の軸方向距離が変化して、前記弾性手段が収容されるスペースの軸方向長さが変化し、もって、前記弾性手段の付勢力が変化して、該摩擦ダンパーで生じるトルクが変化するようにした。
そのため、本発明の摩擦ダンパーでは、内側部材と外側部材の相対的な回転変位に応じてトルクの値を変化させることができ、したがって、内側部材と外側部材の相対的な回転変位に応じてトルクの値を変化させたい箇所に本発明の摩擦ダンパーを用いることが可能となる。
【図面の簡単な説明】
【図１】アクセルペダル装置の平面図である。
【図２】アクセルペダル装置の側面図である。
【図３】（Ａ）は摩擦ダンパーの端面図、（Ｂ）はアクセルペダルを踏み込みコイルスプリングが圧縮された状態の摩擦ダンパーの断面正面図、（Ｃ）はアクセルペダルから足が離れている状態でコイルスプリングが圧縮されていない状態の摩擦ダンパーの断面正面図、（Ｄ）は摩擦ダンパーの端面図で、（Ｂ）、（Ｃ）は（Ｄ）のＥＥ線断面に相当している。
【図４】摩擦ダンパーを構成する部材の説明図で、上段に描かれた絵は各部材の正面図を、中段に描かれた絵は各部材の側面図を示している。
【図５】第１の可変板と第２の可変板の説明図である。
【図６】止めキャップを内側部材に抜落不能に取着する説明図である。
【図７】（Ａ）は摩擦ダンパーの端面図、（Ｂ）はアクセルペダルから足が離れている状態でコイルスプリングが圧縮されていない状態の摩擦ダンパーの断面正面図、（Ｃ）は摩擦ダンパーの端面図で、（Ｂ）は（Ｃ）のＤＤ線断面に相当している。
【図８】摩擦ダンパーを構成する部材の説明図で、上段に描かれた絵は各部材の正面図を、中段に描かれた絵は各部材の側面図を示している。
【符号の説明】
１２アクセルペダル装置
２２枢軸
２４，５２摩擦ダンパー
２６，５４内側部材
２８，５６外側部材
３０，５８環状空間
３４，６２コイルスプリング
３８，６４付勢力可変手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a friction damper.
[0002]
[Prior art]
Generally, the friction damper includes an inner member that extends in a shaft shape, a cylindrical outer member that is coaxial with the inner member and disposed on the outer side of the inner member, and an outer side of the inner member that is on the inner side of the outer member. A first portion that rotates integrally with the inner member in the annular space; a second portion that rotates integrally with the outer member in the annular space; and elastic means that presses the first portion and the second portion. It has.
Then, a frictional force is generated between the first part and the second part, and a torque is generated in the friction damper. Although the value of this torque can be adjusted, the inner member and the outer member are constant. The torque value does not change according to the relative rotational displacement.
On the other hand, depending on the location where the friction damper is used, there may be a case where it is desired to change the torque value in accordance with the relative rotational displacement of the inner member and the outer member.
[0003]
[Problems to be solved by the invention]
However, the conventional friction damper has a problem that the torque value is constant as described above and cannot be used in such a place.
The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide a friction damper capable of changing the value of torque according to the relative rotational displacement of an inner member and an outer member. There is.
[0004]
[Means for Solving the Problems]
  In order to achieve the above object, a friction damper according to the present invention includes an inner member extending in a shaft shape, and a cylindrical outer member disposed coaxially with the inner member and outside the inner member, The outer member has a cylindrical portion and a flange portion projecting inward in the radial direction formed at one end in the longitudinal direction of the cylindrical portion, and a through hole is formed at the center of the flange portion. One end of the inner member is fitted to the inner periphery of the hole, and an annular space is defined between the outer peripheral surface of the inner member and the inner peripheral surface of the cylindrical portion of the outer member. A friction engagement portion, an elastic means, and a biasing force variable means are disposed in the space. The friction engagement portion is integrated with the first portion that rotates integrally with the inner member and the outer member. Rotating and comprising a second part provided to be able to contact the first part in the axial direction And the elastic means is configured to urge the first portion of the friction engagement portion and the second portion of the friction engagement portion in contact with each other and press in a pressing direction. The biasing force varying means includes an annular inner variable member that rotates integrally with the inner member, and an annular outer variable member that is disposed to face the inner variable member and rotates integrally with the outer member. In addition, a cam portion is formed on each of the surface of the inner variable member that faces the outer variable member and the surface of the outer variable member that faces the inner variable member, and each of the cam portions isTwoThe base,ThemProtruding from the baseIn this way, the two formed at equal intervals in the circumferential directionA convex part,eachBase andeachAn inclined portion that connects the convex portion,The convex portion of the cam portion of the outer variable member is always in contact with any one of the base portion, the inclined portion, and the convex portion of the cam portion of the inner variable member, and the cam portion of the inner variable member. The convex portion is always in contact with any one of the base portion, the inclined portion, and the convex portion of the cam portion of the outer variable member, and the base portion of the cam portion of the outer variable member includes the base portion. The cam of the outer variable member is opposed to the base portion of the cam portion of the inner variable member, which has a longer circumferential length than the convex portion of the cam portion of the inner variable member. Has a circumferential length longer than the convex part of the part,With the above configuration, the axial distance between the inner variable member and the outer variable member changes according to the relative rotational displacement between the inner member and the outer member, and the elastic means accommodates The axial length of the space to be changedShiTherefore, the biasing force of the elastic meansTo change the torque generated by the friction damper.It is characterized by that.
  Further, the present invention is characterized in that a shaft insertion hole extending in the axial direction is formed through the center of the inner member.
  Further, according to the present invention, a flange portion protruding radially outward is formed at an axial end portion of the inner member, and the first portion of the friction engagement portion is constituted by the flange portion. It is characterized by being.
  In the present invention, a friction plate that rotates integrally with the inner member is disposed in the annular space so as to be movable in the axial direction, and the first portion of the friction engagement portion is constituted by the friction plate. It is characterized by.
  Further, the present invention is characterized in that the second portion of the friction engagement portion is constituted by the flange portion of the outer member.
  Further, according to the present invention, a friction plate that rotates integrally with the outer member is disposed in the annular space so as to be movable in the axial direction, and the second portion of the friction engagement portion is constituted by the friction plate. It is characterized by.
  Further, the present invention is characterized in that the elastic means is disposed between the friction engagement portion and the biasing force varying means in the annular space.
  Further, the present invention is characterized in that there is provided regulating means for regulating movement of the biasing force varying means in a direction away from the friction engagement portion.
  In the present invention, the inner member is coupled to a rotating shaft so as to be integrally rotatable with the shaft, and the outer member is non-rotatably coupled to a member that rotatably supports the shaft. The second portion is not rotatable together with the outer member.
[0005]
According to the present invention, when a relative rotational displacement occurs between the inner member and the outer member, the urging force of the elastic means for pressing the first portion and the second portion is changed by the urging force variable means.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the case where the friction damper which concerns on embodiment of this invention is attached to the pivot of the accelerator pedal of a vehicle is demonstrated.
First, from the first embodiment, FIG. 1 is a plan view of an accelerator pedal device, and FIG. 2 is a side view thereof.
The accelerator pedal device 12 includes a bracket 14 attached to the vehicle body side, an accelerator pedal 16 swingably provided on the bracket 14, a torsion spring 18 that biases the accelerator pedal 16 upward, a friction damper 24, and the like. ing.
The accelerator pedal device 12 according to the present embodiment opens and closes a throttle in the case of a gasoline engine and operates a fuel injection device in the case of a diesel engine by a stepping operation as in the conventional case. In addition, a cable that connects the accelerator pedal and the throttle or between the accelerator pedal and the fuel injection device is not used. That is, an actuator is connected to a throttle and a fuel injection device where a conventional cable is connected, and the swing displacement of the accelerator pedal 16 is transmitted to a projector 20A, a light receiver 20B, and a slit is formed on the outer periphery thereof. It is detected by an angle sensor 20 composed of an integrally rotating disk 20C and the like, and an actuator is driven through a controller based on a detection signal detected by the angle sensor 20, thereby operating a throttle and a fuel injection device. .
[0007]
The bracket 14 includes a bottom plate portion 1402 fixed to the vehicle body side by screws 1401 and side plate portions 1404 that stand up from both sides of the bottom plate portion 1402 and face each other.
The pivot 22 is inserted between the both side plate portions 1404 and is rotatably supported.
The accelerator pedal 16 includes a rod 1602 and a pedal portion 1604 attached to one end in the longitudinal direction of the rod 1602, and the other end of the rod 1602 is outside one side plate portion 1404 at the end of the pivot shaft 22. It is fixed by welding.
[0008]
The torsion spring 18 and the friction damper 24 are disposed on the pivot 22 portion inside the both side plate portions 1404.
One end of the torsion spring 18 protrudes from the notch 1408 of one side plate portion 1404 to the outside of the side plate portion 1404 and is locked to the upper surface of the rod 1602, and the other end is locked to the hole of the other side plate portion 1404. The intermediate coil portion is wound around the pivot 22 between the side plate portions 1404, whereby the accelerator pedal 16 has the pedal portion 1604 positioned at a predetermined upper limit position, and when the pedal portion 1604 is depressed, the upper limit position is reached. An urging force in the direction of returning to the position is generated.
[0009]
3A is an end view of the friction damper, FIG. 3B is a sectional front view of the friction damper when the accelerator pedal is depressed and the coil spring is compressed, and FIG. 3C is a coil with the foot away from the accelerator pedal. A sectional front view of the friction damper in a state where the spring is not compressed, (D) is an end view of the friction damper, and (B) and (C) correspond to an EE line section of (D). FIG. 4 is an explanatory diagram of members constituting the friction damper. The picture drawn in the upper part shows a front view of each member, and the picture drawn in the middle part shows a side view of each member.
As shown in FIGS. 3 and 4, the friction damper 24 includes an inner member 26 that extends in a shaft shape, and a cylindrical outer surface that is coaxial with the inner member 26 and disposed outside the inner member 26. A member 28, a friction plate 32 disposed in an annular space 30 radially outside the inner member 26 and radially inside the outer member 28, and a coil spring (elastic means) for biasing the friction plate 32 in the axial direction. ) 34, a friction engagement portion 36 that generates a torque by a frictional force, a biasing force varying means 38 that makes the biasing force of the coil spring 34 variable, a washer 40, a stop cap 42 (regulating means), and the like. .
[0010]
A shaft insertion hole 2602 extending in the axial direction is formed through the center of the inner member 26, and the cross section of the hole 2602 is the same as the pivot 22 and has a shape in which a part of a circle is cut out. The inner member 26 and the pivot 22 are configured to rotate integrally by inserting the pivot 22 through 2602.
A flange portion 2604 that bulges outward in the radial direction is formed at one end in the axial direction of the inner member 26, and a convex portion that protrudes outward in the radial direction at equal intervals in the circumferential direction at the other end in the axial direction. Four portions 2606 are formed. In addition, four recesses 2608 are formed on the outer peripheral portion of the inner member 26 so as to be open at the other end at equal intervals in the circumferential direction and extending in the axial direction.
[0011]
The outer member 28 includes a cylindrical portion 2802 and a flange portion 2804 that is formed to bulge inward in the radial direction at the axial end of the cylindrical portion 2802.
Four cylindrical recesses 2806 are formed in the inner circumferential portion of the cylindrical portion 2802 at equal intervals in the circumferential direction and extending in the axial direction, and the outer end surface of the flange portion 2804 is formed at the end of the cylindrical portion 2802. Two leg portions 2808 projecting in the axial direction are formed. As shown in FIG. 1, the leg portion 2808 is inserted and fixed in the hole of the side plate portion 1404, so that the outer member 28 is non-rotatably attached to the side plate portion 1404.
In addition, a hole is formed through the center of the flange portion 2804, and the inner member 26 is inserted into the hole, and the inner member is disposed inside the cylindrical portion 2802 of the outer member 28 with the flange portions 2604 and 2804 in contact with each other. 26 extends coaxially, and the annular space 30 is formed outside the inner member 26 inside the cylindrical portion 2802.
Then, the outer member 28 is non-rotatably attached to the side plate portion 1404 so that the flange portion 2604 of the inner member 26 is between the flange portion 2804 and the side plate portion 1404 of the outer member 28 as shown in FIG. Thus, the inner member 26 is disposed so as not to move in the axial direction, in other words, relatively immovable relative to the outer member 28 in the axial direction.
[0012]
In the present embodiment, first to fifth five types of friction plates 3201, 3202, 3203, 3204, 3205 are used as the friction plates 32 disposed in the annular space 30.
Each of the first to fifth friction plates 3201, 3202, 3203, 3204, and 3205 has an annular plate shape, and the inner member 26 is inserted through the center hole thereof and arranged in the annular space 30 in that order. The same friction plate is used as the second friction plate 3202 and the fourth friction plate 3204.
Among the friction plates, the first, third, and fifth friction plates 3201, 3203, and 3205 are spaced from each other between the four protrusions 3210 and the protrusions 3210 at equal intervals in the circumferential direction on the inner periphery of the center holes. Recesses 3211 are respectively formed in the first and second friction plates 3201, 3203, 3205, which are engaged with the recesses 2608 of the inner member 26 in a state where the inner member 26 is inserted. Rotates integrally with the inner member 26. The concave portion 3211 is for allowing the convex portion 2606 formed on the inner member 26 to pass when the first, third, and fifth friction plates are inserted into the outer periphery of the inner member 26.
Among the friction plates, the second and fourth friction plates 3202 and 3204 are formed with four convex portions 3212 at equal intervals in the circumferential direction on the outer periphery thereof, and the inner member 26 is inserted through these convex portions 3212. In this embodiment, the second and fourth friction plates 3202 and 3204 are coupled to rotate integrally with the outer member 28. However, in the present embodiment, the outer member 28 is attached to the side plate portion 1404 in a non-rotatable manner, the second and fourth friction plates 3202 and 3204 do not rotate, and remain stationary integrally with the outer member 28.
Then, as will be described later, these friction plates 32 are pressed between the flange portion 2804 and the coil spring 34 by the coil spring 34, and the inner member 26 rotates, so that the flange portion 2804, the second, Since the first, third, and fifth friction plates 3201, 3203, and 3205 rotate with respect to the fourth friction plates 3202 and 3204, a frictional force is generated between the friction plates 32, and torque is applied to the friction damper 24. appear. In the present embodiment, the friction engagement portion 36 is configured by the flange portions 2604 and 2804 and the friction plate 32.
[0013]
The first to fifth friction plates 3201, 3202, 3203, 3204, and 3205 are formed of, for example, a thermoplastic resin composition, and the thermoplastic resin composition is a base resin and a first resin added to the base resin. The base resin is a polyacetal resin or a polyphenylene sulfide resin, and the first additive is composed of an olefin polymer, a styrene polymer, and a fluorine polymer. The one or more selected second additives are one or more selected from lubricating oils, waxes, fatty acids, graphite, molybdenum disulfide and phosphates.
[0014]
As the polyacetal resin, besides the polyacetal homopolymer, a polyacetal copolymer in which most of the main chain is an oxymethylene chain can be used.
Furthermore, a resin obtained by modifying polyacetal by crosslinking or graft copolymerization by a known method can also be used.
Specific examples include homopolymer “Delrin (trade name)” manufactured by EI DuPont and copolymer “Duracon (trade name)” manufactured by Polyplastics.
The polyphenylene sulfide resin may be either a cross-linked type or a linear type. Specifically, “Ryton (trade name)” manufactured by Philips, “Toprene PPS (trade name)” manufactured by Toprene, Kureha Chemical Industries, Ltd. “Fortron (trade name)” can be mentioned.
[0015]
The first additive is used to improve the sliding characteristics of the base resin.
As a 1st additive, 1 type (s) or 2 or more types selected from an olefin type polymer, a styrene type polymer, and a fluorine-type polymer are added.
Examples of the olefin polymer include homopolymers such as polyethylene and polypropylene, and copolymers having these as main components.
Examples of the copolymer include ethylene-α olefin copolymer, ethylene-propylene-diene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-glycidyl methacrylate copolymer, ethylene-ethyl. Examples include acrylate-maleic anhydride copolymers.
Furthermore, a copolymer obtained by grafting polystyrene, polymethyl methacrylate, or acrylonitrile-styrene copolymer onto the homopolymer and the copolymer is also included.
The olefin polymer is used alone or in the form of a mixture of two or more or reaction products.
The styrene polymer used in the present invention is a triblock copolymer or a radial block copolymer having a polystyrene-rubber intermediate block-polystyrene structure.
Examples of the rubber intermediate block include polybutadiene, polyisoprene, and hydrogenated products thereof.
Specific examples of the block copolymer include polystyrene-polybutadiene-polystyrene block copolymer, polystyrene-polyisoprene-polystyrene block copolymer, polystyrene-poly (ethylene / butylene) -polystyrene block copolymer, and polystyrene-poly. (Ethylene / propylene) -polystyrene block copolymer.
Furthermore, in this invention, what introduce | transduced the functional group into the said block copolymer can also be used.
As the functional group to be introduced, maleic acid, endocis-dicyclo [2,2,1] hept-5-ene-2,3-dicarboxylic acid (nadic acid), maleic anhydride, citraconic anhydride, itaconic anhydride, Examples include tetrahydrophthalic anhydride, nadic anhydride, methyl nadic anhydride, monomethyl maleate, dimethyl maleate, dimethyl itaconate, dimethyl citraconic acid, maleimide, and maleyl chloride, especially maleic acid, nadic acid or these The acid anhydride is preferred.
Examples of the fluoropolymer include polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-ethylene copolymer, polychlorotrifluoroethylene, Examples include chlorotrifluoroethylene-ethylene copolymer, polyvinylidene fluoride, and polyvinyl fluoride.
The blending amount of the first additive is 0.3 to 10% by weight, preferably 0.5 to 7% by weight for the olefin polymer, and 0.1 to 10% by weight for the styrene polymer, preferably The amount is 0.3 to 6% by weight, and the fluorine-based polymer is 2 to 50% by weight, preferably 2 to 40% by weight.
[0016]
The second additive is used in addition to the first additive in order to further improve the sliding characteristics.
As the second additive, one or more selected from lubricating oil, wax, fatty acid, graphite, molybdenum disulfide and phosphate are added.
Examples of the lubricating oil include engine oil, spindle oil, turbine oil, machine oil, cylinder oil, mineral oil such as gear oil, vegetable oil such as castor oil, animal oil such as whale oil, and synthetic oil such as silicone oil.
Examples of the wax include paraffin wax, fatty acid ester derived from higher fatty acid, fatty acid amide, fatty acid salt and the like.
Examples of the phosphate include alkali metal or alkaline earth metal tertiary phosphate, secondary phosphate, pyrophosphate, phosphite, and metaphosphate. Specifically, lithium triphosphate (Li_ThreePO_Four), Lithium diphosphate (Li₂HPO_Four), Lithium pyrophosphate (Li_FourP₂O₇), Tricalcium phosphate (Ca_Three(PO_Four)₂), Dicalcium phosphate (CaHPO)_FourOr CaHPO_Four・ 2H₂O) and calcium pyrophosphate (Ca₂P₂O₇).
The amount of the second additive is 0.1 to 10% by weight, preferably 0.3 to 6% by weight.
[0017]
A third additive may be used for the purpose of reinforcing the thermoplastic resin composition.
As the third additive, one or more selected from glass powder, carbon powder (excluding graphite), glass fiber, carbon fiber, aramid fiber, potassium titanate whisker, metal fiber, metal powder, and the like are used. It mix | blends in the ratio of 10 weight% or less.
[0018]
After the first to fifth friction plates 3201, 3202, 3203, 3204, and 3205 as described above are disposed in the annular space 30 in that order, the coil spring 34 faces the fifth friction plate 3205. Next, the washer 40 and the urging force variable means 38 are disposed, and finally the stop cap 42 is disposed.
The coil spring 34 has a material, a wire diameter, a winding diameter, and the number of turns determined so as to obtain a desired hysteresis characteristic.
The washer 40 is for initial torque setting, and three washers are used in this embodiment.
[0019]
The biasing force varying means 38 includes first and second variable plates 38A and 38B facing each other, and both are formed in an annular plate shape.
Four convex portions 3810 projecting outward in the radial direction are formed at equal intervals in the circumferential direction on the outer periphery of the first variable plate (outer variable member) 38A, and these convex portions 3810 are formed on the outer member 28. The first variable plate 38A is coupled so as to rotate integrally with the outer member 28, but in this embodiment, the outer member 28 is non-rotatably attached to the side plate portion 1404. Therefore, the first variable plate 38A also does not rotate and remains stationary integrally with the outer member 28.
Four convex portions 3812 protruding inward in the radial direction are formed at equal intervals in the circumferential direction on the inner periphery of the second variable plate 38B (inner variable member), and these convex portions 3812 are formed on the inner member. 26, the second variable plate 38 </ b> B rotates integrally with the inner member 26.
[0020]
  As shown in FIG. 5, cam portions 3822 and 3824 that can be engaged with each other are formed on the outer periphery of the surface where the first and second variable plates 38A and 38B face each other. ,TwoA base 3832;ThemProtrudes from base 3832In this way, the two formed at equal intervals in the circumferential directionA convex portion 3834;eachBase 3832 andeachConvex part 3834WhenIs provided with an inclined portion 3836.Then, the base portion 3832 of the cam portion 3822 of the variable plate 38A has a longer circumferential length than the convex portion 3834 of the cam portion 3824 of the variable plate 38B facing the base portion 3832, and the cam portion 3824 of the variable plate 38B. The base portion 3832 has a circumferential length longer than the convex portion 3834 of the cam portion 3822 of the variable plate 38A that the base portion 3832 faces.The retaining cap 42 is formed in an annular plate shape, and four concave portions 4202 projecting radially inwardly are formed on the inner periphery thereof at equal intervals in the circumferential direction. Engaging with the portion 2606, the stop cap 42 rotates integrally with the inner member 26.
[0021]
Further, two protrusions 4204 protruding in the axial direction are formed on the end face of the stop cap 42 at equal intervals in the circumferential direction. This convex portion 4204 is for facilitating the operation when the stopper cap 42 is attached and detached.
The first to fifth friction plates 3201, 3202, 3203, 3204, 3205, the coil spring 34, the washer 40, the first variable plate 38A, and the second variable plate 38B are arranged in the annular space 30 in that order. After being disposed at 30, a stop cap 42 is disposed, and is attached to the inner member 26 so as not to be pulled out using a snap ring 4210 as shown in FIG. 1.
For example, as shown in FIG. 6, a structure in which the stopper cap 42 is attached to the inner member 26 so as not to be removed is formed by forming a female screw on the inner periphery of the stopper cap 42 and a male screw at the tip of the inner member 26. May be used, and a screw coupling 4220 between the female screw and the male screw may be used.
[0022]
  In the present embodiment, the pedal portion 1604 is at the upper limit position with the foot away from the accelerator pedal 16, and the friction damper 24 is in the state shown in FIG. That is, the convex portion 3834 of the cam portion 3822 of the first variable plate 38A corresponds to the cam portion 382 of the second variable plate 38B.4And a cam portion 382 of the second variable plate 38B.4The convex portion 3834 abuts on the base portion 3832 of the cam portion 3822 of the first variable plate 38A, and the first variable plate 38A andSecond variable plate 38BThe axial dimension between them is the smallest, and the axial dimension of the space in which the coil spring 34 is accommodated in the annular space 30 is the largest. When the accelerator pedal 16 is depressed, the pivot 22 starts rotating from this state, and the inner member 26 starts rotating. At this time, the initial torque generated between the friction plates 32 is changed by changing the number of washers 40 or It is easily adjusted by changing to a washer 40 having a different thickness.
[0023]
  Next, when the accelerator pedal 16 is depressed, a torque having a value obtained by adding the torque generated by the elastic force of the coil spring 18 and the torque generated by the friction damper 24 is applied to the foot as a load. In this case, the convex portion 3834 of the cam portion 3822 of the first variable plate 38A corresponds to the cam portion 382 of the second variable plate 38B.4Of the second variable plate 38B.4While the convex portion 3834 is in contact with the base portion 3832 of the cam portion 3822 of the first variable plate 38A, the torque generated in the friction damper 24 is constant.
[0024]
  The accelerator pedal 16 is further stepped on, and the convex portion 3834 of the cam portion 3822 of the first variable plate 38A becomes the cam portion 382 of the second variable plate 38B.4The cam portion 382 of the second variable plate 38B.4When the convex portion 3834 contacts the inclined portion 3836 of the cam portion 3822 of the first variable plate 38A, the first variable plate 38A and the first variable plate 38A follow the depression amount of the accelerator pedal 16.Second variable plate 38BSince the axial dimension between them increases, the coil spring 34 is compressed, and the force pressing between the friction plates 32 increases, so that the torque generated in the friction damper 24 gradually increases. A torque having a value obtained by adding a torque generated by the elastic force of the coil spring 18 and a gradually increasing torque generated by the friction damper 24 is applied to the foot as a load.
[0025]
  When the accelerator pedal 16 is further depressed and the pedal portion 1604 reaches the lower limit position, as shown in FIG. 3B, the convex portion 3834 of the cam portion 3822 of the first variable plate 38A becomes the cam of the second variable plate 38B. Part 3824The cam portion 382 of the second variable plate 38B.4Of the first variable plate 38A is in contact with the convex portion 3834 of the cam portion 3822 of the first variable plate 38A.Second variable plate 38BThe axial dimension between them is maximized, and the axial dimension of the space in which the coil spring 34 is accommodated in the annular space 30 is minimized. As a result, the amount of compression of the coil spring 34 is maximized and the force for pressing between the friction plates 32 is maximized, so that the torque generated in the friction damper 24 is maximized. A torque obtained by adding the torque generated by the elastic force of the coil spring 18 and the maximum torque generated by the friction damper 24 is applied to the foot as a load at the lower limit position of the pedal portion 1604.As is clear from the above description, the convex portion 3834 of the cam portion 3822 of the variable plate 38A is always in contact with any one of the base portion 3832, the inclined portion 3836, and the convex portion 3834 of the cam portion 3824 of the variable plate 38B. The convex portion 3834 of the cam portion 3824 of the variable plate 38B is always in contact with any one of the base portion 3832, the inclined portion 3836, and the convex portion 3834 of the cam portion 3822 of the variable plate 38A.
[0026]
  As described above, in the present embodiment, when the accelerator pedal 16 is depressed, a torque obtained by adding the torque generated by the elastic force of the coil spring 18 and the torque generated by the friction damper 24 is applied to the foot as a load. The initial torque of the friction damper 24 can be easily adjusted by changing the number of washers 40 or by changing to a washer 40 having a different thickness. The torque generated in the friction damper 24 can be easily adjusted to a desired value by appropriately selecting the material, wire diameter, winding diameter, number of turns of the coil spring 34, and the material of the friction plate 32. Further, the timing at which the torque generated by the friction damper 24 is increased or decreased and the rate at which the torque is increased or decreased are also determined by the cam portion 3822., 3824By changing the shape, it can be easily adjusted to a desired value. From these facts, the torque obtained by adding the load applied to the foot, that is, the torque generated by the elastic force of the coil spring 18 and the torque generated by the friction damper 24, that is, the hysteresis characteristic can be easily set to a desired value. Is possible.
[0027]
Therefore, according to the present embodiment, the same load as that in the case of using the cable can be simplified even if the cable connecting the accelerator pedal and the throttle or between the accelerator pedal and the fuel injection device is omitted as in the prior art. The accelerator pedal device 12 can be configured using an angle sensor, a controller, and an actuator.
And since the cable is omitted, it is possible to make the area around the accelerator pedal 16, particularly around the bracket 14, compact.
[0028]
Next, a friction damper according to a second embodiment applied to an accelerator pedal device for a vehicle as in the first embodiment will be described.
7A is an end view of the friction damper, FIG. 7B is a sectional front view of the friction damper in a state where the foot is separated from the accelerator pedal and the coil spring is not compressed, and FIG. 7C is an end view of the friction damper. In the figure, (B) corresponds to the cross section along line DD of (C). FIG. 8 is an explanatory diagram of members constituting the friction damper. The picture drawn in the upper part shows a front view of each member, and the picture drawn in the middle part shows a side view of each member.
Similar to the first embodiment, the friction damper 52 according to the second embodiment is used in the accelerator pedal device shown in FIGS. 1 and 2, and the friction damper 52 extends in a shaft shape. An inner member 54, a cylindrical outer member 56 that is coaxial with the inner member 54 and disposed outside the inner member 54, and an annular shape radially outside the inner member 54 and radially inward of the outer member 56 A friction engagement portion 60 provided in the space 58, a coil spring (elastic means) 62 that presses the friction engagement portion 60, a biasing force variable means 64 that makes the pressing force of the coil spring 62 variable, a washer 66, and a stop cap 68 and the like.
[0029]
A shaft insertion hole 5402 extending in the axial direction is formed through the center of the inner member 54, and the cross section of the hole 5402 is the same as the cross section of the pivot shaft 22 as in the first embodiment. By inserting the pivot 22 into the hole 5402, the inner member 54 and the pivot 22 are configured to rotate integrally.
A flange portion 5404 bulging outward in the radial direction is formed at one end in the axial direction of the inner member 54, and a male screw 5406 is formed at the other end in the axial direction of the inner member 54.
[0030]
The outer member 56 includes a cylindrical portion 5602, and a flange portion 5604 formed to bulge inward in the radial direction at an end portion in the axial direction of the cylindrical portion 5602. The friction engagement portion 60 is configured by the flange portion 5404 of the member 54.
Four concave portions 5606 are formed in the inner circumferential portion of the cylindrical portion 5602 at equal intervals in the circumferential direction and extending in the axial direction, and the outer end surface of the flange portion 5604 is formed at the end of the cylindrical portion 5602. As in the first embodiment, two leg portions 5608 are formed which are inserted into the holes of the side plate portion 1404 and fixed.
In addition, a hole is formed through the center of the flange portion 5604, and the inner member 54 is inserted into the hole, and the inner member is disposed inside the cylindrical portion 5602 of the outer member 56 with the flange portions 5404 and 5604 in contact with each other. 54 extends coaxially, and the annular space 58 is formed outside the inner member 54 inside the cylindrical portion 5602.
[0031]
A retaining ring 57 is attached to the tip of the inner member 54 protruding from the center hole of the flange portion 5604, and the flange portion 5604 of the outer member 56 is sandwiched between the retaining ring 57 and the flange portion 5404, As a result, the inner member 54 is disposed so as not to move in the axial direction, in other words, relatively immovable relative to the outer member 56 in the axial direction.
In the second embodiment, unlike the first embodiment, a friction plate separate from the inner member 54 and the outer member 56 is not used, and the flange portions 5404 and 5604 are used in the first embodiment. As will be described later, these flange portions 5404 and 5604 are pressed against each other by the coil spring 62, and the inner member 54 rotates to cause the flange portion 5404 to move relative to the flange portion 5604. Since it rotates, a frictional force is generated between the flange portions 5404 and 5604, and a torque is generated in the friction damper 52. The material of the flange portions 5404 and 5604 can be the same as that of the friction plate of the first embodiment.
[0032]
After the inner member 54 and the outer member 56 are assembled as described above, the coil spring 62 is disposed in the annular space 58, followed by the washer 66 and the stopper cap 68.
The material, wire diameter, winding diameter, and number of turns of the coil spring 62 are determined so that desired hysteresis characteristics can be obtained.
The washer 66 is for setting an initial torque, and three washers are used in this embodiment.
[0033]
The stopper cap 68 is formed in a cylindrical shape, an internal thread 6802 is formed on the inner periphery thereof, and four convex portions 6804 protruding outward in the radial direction are formed on the outer peripheral portion at equal intervals in the circumferential direction. These convex portions 6804 engage with the concave portions 5606 of the outer member 56, and the stopper cap 68 is coupled so as to rotate integrally with the outer member 56. However, as in the first embodiment, the outer member 56 is coupled. Is attached to the side plate portion 1404 in a non-rotatable manner, so that the stop cap 68 does not rotate and is stationary with the outer member 56.
Further, two protrusions 6806 protruding in the axial direction are formed on the end face of the stop cap 68 at equal intervals in the circumferential direction. This convex portion 6806 is for facilitating the operation when the stopper cap 68 is attached and detached.
After the inner member 54 and the outer member 56 are assembled, the coil spring 62 and the washer 66 are disposed in the annular space 58, and then the stop cap 68 is disposed by coupling the male screw 5406 and the female screw 6802. The coil spring 62 and the washer 66 cannot be removed from the space 58.
[0034]
In the present embodiment, the pedal portion 1604 is in the upper limit position with the foot away from the accelerator pedal 16, and the friction damper 52 is in the state shown in FIG.
That is, the axial dimension between the flange portion 5604 of the outer member 56 and the stopper cap 68 is maximized. In this state, the flange portion 5604 of the outer member 56 and the flange portion 5404 of the inner member 54 abut against each other by the coil spring 62. ing.
When the accelerator pedal 16 is depressed, the pivot 22 starts to rotate from this state, and the inner member 54 begins to rotate. At this time, the initial torque generated between the flange portions 5404 and 5604 is changed by changing the number of washers 66. Alternatively, it can be easily adjusted by changing to a washer 66 having a different thickness.
[0035]
Next, when the accelerator pedal 16 is depressed, a torque having a value obtained by adding the torque generated by the elastic force of the coil spring 18 and the torque generated by the friction damper 52 is applied to the foot as a load.
In this case, when the pivot 22 and the inner member 54 are rotated by depressing the accelerator pedal 16, the stop cap 68 is coupled to the inner member 54 by the male screw 5406 and the female screw 6802, and at the same time, the outer member is engaged by the engagement between the convex portion 6804 and the concave portion 5606. 56, the stop cap 68 moves in a direction approaching the flange portion 5604 of the outer member 56 following the depression of the accelerator pedal 16. As a result, the axial dimension between the flange portion 5604 and the stop cap 68 of the outer member 56 is reduced, the coil spring 62 is compressed, and the force for pressing between the flange portions 5404 and 5604 is increased. The torque generated by the is gradually increased. In the present embodiment, the biasing force varying means 64 is constituted by the stop cap 68, the screw 5406, the male screw 6802, the convex portion 6804, and the concave portion 5606.
A torque having a value obtained by adding a torque generated by the elastic force of the coil spring 18 and a gradually increasing torque generated by the friction damper 52 is applied to the foot as a load.
[0036]
As described above, also in the second embodiment, when the accelerator pedal 16 is depressed, the torque that is the sum of the torque generated by the spring force of the coil spring 18 and the torque generated by the friction damper 52 is applied to the foot as a load. .
The initial torque of the friction damper 52 can be easily adjusted by changing the number of washers 66 or by changing to the washers 40 having different thicknesses.
Further, the torque generated in the friction damper 52 can be easily adjusted to a desired value by appropriately selecting the material of the coil spring 62, the wire diameter, the winding diameter, the number of turns, and the material of the flange portions 5404 and 5604.
Further, the rate at which the torque generated in the friction damper 52 increases in accordance with the rotational displacement of the inner member 54 can be easily adjusted to a desired rate by changing the pitch between the male screw 5406 and the female screw 6802.
From these facts, the torque obtained by adding the load applied to the foot, that is, the torque generated by the elastic force of the coil spring 18 and the torque generated by the friction damper 52, that is, the hysteresis characteristic can be easily set to a desired value. Is possible.
[0037]
Therefore, according to the second embodiment, even if the cable connecting the accelerator pedal and the throttle or between the accelerator pedal and the fuel injection device is omitted as in the prior art, the same load as when the cable is used is used. It can be easily applied to the foot, and the accelerator pedal device 12 can be configured by using an angle sensor, a controller, and an actuator, and since the cable is omitted, the area around the accelerator pedal 16, especially around the bracket 14, is made compact. It becomes possible.
In the first and second embodiments, the friction damper is applied to the accelerator pedal device. However, the friction damper of the present invention is not limited to the accelerator pedal device, and the relative relationship between the inner member and the outer member. This is applied to all cases where it is desired to change the torque value according to the rotational displacement.
[0038]
【The invention's effect】
  As described above, the friction damper of the present invention includes an inner member that extends in a shaft shape, and a cylindrical outer member that is coaxial with the inner member and disposed outside the inner member. The member has a cylindrical portion and a flange portion projecting radially inwardly formed at one end in the longitudinal direction of the cylindrical portion, and a through hole is formed at the center of the flange portion. One end of the inner member is fitted to the inner periphery of the inner member, and an annular space is defined between the outer peripheral surface of the inner member and the inner peripheral surface of the cylindrical portion of the outer member. Further, a friction engagement portion, an elastic means, and a biasing force variable means are disposed, and the friction engagement portion rotates integrally with the inner member and the outer member. And a second portion provided so as to be able to contact the first portion in the axial direction. And the elastic means is configured to urge the first portion of the friction engagement portion and the second portion of the friction engagement portion to come into contact with each other and to press them. The force variable means includes an annular inner variable member that rotates integrally with the inner member, and an annular outer variable member that is disposed so as to face the inner variable member and rotates integrally with the outer member, Cam portions are respectively formed on a surface of the inner variable member that faces the outer variable member and a surface of the outer variable member that faces the inner variable member, and each of the cam portions isTwoThe base,ThemProtruding from the baseIn this way, the two formed at equal intervals in the circumferential directionA convex part,eachBase andeachAn inclined portion that connects the convex portion,The convex portion of the cam portion of the outer variable member is always in contact with any one of the base portion, the inclined portion, and the convex portion of the cam portion of the inner variable member, and the cam portion of the inner variable member. The convex portion is always in contact with any one of the base portion, the inclined portion, and the convex portion of the cam portion of the outer variable member, and the base portion of the cam portion of the outer variable member includes the base portion. The cam of the outer variable member is opposed to the base portion of the cam portion of the inner variable member, which has a longer circumferential length than the convex portion of the cam portion of the inner variable member. Has a circumferential length longer than the convex part of the part,With the above configuration, the axial distance between the inner variable member and the outer variable member changes according to the relative rotational displacement between the inner member and the outer member, and the elastic means accommodates The axial length of the space to be changedShiTherefore, the biasing force of the elastic meansTo change the torque generated by the friction damper..
  Therefore, in the friction damper of the present invention, the torque value can be changed according to the relative rotational displacement between the inner member and the outer member, and therefore the torque according to the relative rotational displacement between the inner member and the outer member. It is possible to use the friction damper of the present invention at a location where it is desired to change the value of.
[Brief description of the drawings]
FIG. 1 is a plan view of an accelerator pedal device.
FIG. 2 is a side view of an accelerator pedal device.
3A is an end view of the friction damper, FIG. 3B is a cross-sectional front view of the friction damper when the accelerator pedal is depressed and the coil spring is compressed, and FIG. 3C is a state in which the foot is separated from the accelerator pedal. 3D is a sectional front view of the friction damper in a state where the coil spring is not compressed, FIG. 4D is an end view of the friction damper, and FIGS. 5B and 5C correspond to a section taken along line EE in FIG.
FIG. 4 is an explanatory diagram of members constituting the friction damper. The picture drawn in the upper part shows a front view of each member, and the picture drawn in the middle part shows a side view of each member.
FIG. 5 is an explanatory diagram of a first variable plate and a second variable plate.
FIG. 6 is an explanatory diagram for attaching the stopper cap to the inner member so that it cannot be removed.
7A is an end view of the friction damper, FIG. 7B is a sectional front view of the friction damper when the foot is separated from the accelerator pedal and the coil spring is not compressed, and FIG. 7C is the friction damper. (B) is equivalent to the DD line cross section of (C).
FIG. 8 is an explanatory diagram of members constituting the friction damper. The picture drawn in the upper part shows a front view of each member, and the picture drawn in the middle part shows a side view of each member.
[Explanation of symbols]
12 Accelerator pedal device
22 Axis
24,52 Friction damper
26,54 inner member
28, 56 outer member
30, 58 annular space
34, 62 Coil spring
38, 64 biasing force variable means

Claims

An axially extending inner member, and a cylindrical outer member disposed coaxially with the inner member and outside the inner member;
The outer member has a cylindrical portion and a flange portion projecting radially inwardly formed at one end in the longitudinal direction of the cylindrical portion, and a through hole is formed at the center of the flange portion, One end of the inner member is fitted to the inner periphery of the through hole,
An annular space is defined between the outer peripheral surface of the inner member and the inner peripheral surface of the cylindrical portion of the outer member,
In the annular space, a friction engagement portion, an elastic means, and a biasing force variable means are disposed,
The friction engagement portion includes a first portion that rotates integrally with the inner member, and a second portion that rotates integrally with the outer member and is capable of contacting the first portion in the axial direction. And consists of
The elastic means is configured to urge the first portion of the friction engagement portion and the second portion of the friction engagement portion to contact and press in a pressing direction,
The biasing force varying means includes an annular inner variable member that rotates integrally with the inner member, and an annular outer variable member that is disposed to face the inner variable member and rotates integrally with the outer member. , a surface facing the outer variable member of the inner variable member, in the surface facing the inner variable member of the outer variable member, respectively and the cam portion is formed on, each of which cam portion is 2 one of the base comprises two protrusions formed at equal intervals so as to protrude from their base in the circumferential direction, and an inclined portion for connecting each base and each convex section,
The convex portion of the cam portion of the outer variable member is always in contact with any one of the base portion, the inclined portion, and the convex portion of the cam portion of the inner variable member, and the cam portion of the inner variable member. The convex portion is always in contact with any one of the base portion, the inclined portion, and the convex portion of the cam portion of the outer variable member,
The base portion of the cam portion of the outer variable member has a circumferential length longer than the convex portion of the cam portion of the inner variable member facing the base portion, and the cam portion of the inner variable member The base portion has a circumferential length longer than the convex portion of the cam portion of the outer variable member facing the base portion,
With the above configuration, the axial distance between the inner variable member and the outer variable member changes according to the relative rotational displacement between the inner member and the outer member, and the elastic means accommodates the axial length of the space is changed to be, with the biasing force of said resilient means is changed, and so the torque generated by the friction damper is changed,
This is a friction damper.

The friction damper according to claim 1, wherein a shaft insertion hole extending in the axial direction is formed through the center of the inner member.

A flange portion protruding outward in the radial direction is formed at an end portion in the axial direction of the inner member, and the first portion of the friction engagement portion is formed by the flange portion. The friction damper according to claim 1 or 2.

A friction plate rotating integrally with the inner member is disposed in the annular space so as to be movable in the axial direction, and the first portion of the friction engagement portion is constituted by the friction plate. The friction damper according to claim 1, 2, or 3.

The friction damper according to any one of claims 1 to 4, wherein the second portion of the friction engagement portion is formed by the flange portion of the outer member.

A friction plate that rotates integrally with the outer member is disposed in the annular space so as to be movable in the axial direction, and the second portion of the friction engagement portion is constituted by the friction plate. The friction damper according to any one of claims 1 to 5.

The friction damper according to any one of claims 1 to 6, wherein the elastic means is disposed between the friction engagement portion and the biasing force variable means in the annular space.

The friction damper according to any one of claims 1 to 7, further comprising a restricting means for restricting movement of the biasing force varying means in a direction away from the friction engagement portion.

The inner member is coupled to a rotating shaft so as to be integrally rotatable with the shaft, the outer member is non-rotatably coupled to a member that rotatably supports the shaft, and the second portion of the friction engagement portion 9. The friction damper according to claim 1, wherein the friction damper cannot rotate together with the outer member.