JP2004276742A

JP2004276742A - Seat belt retractor and its retracting method

Info

Publication number: JP2004276742A
Application number: JP2003071091A
Authority: JP
Inventors: Yukinori Midorikawa; 幸則緑川; Hiroshi Yamada; 浩山田; Bai Matsuki; 培松木; Iwata Hihata; 岩太日端; Tatsuo Tada; 辰雄多田; Kiyoshi Ogawa; 清志小川; Katsuyasu Ono; 勝康小野
Original assignee: NSK Autoliv Co Ltd
Current assignee: NSK Autoliv Co Ltd
Priority date: 2003-03-14
Filing date: 2003-03-14
Publication date: 2004-10-07

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seat belt retractor and its retracting method carrying out safety protection of an occupant by carrying out adjustment control so as to reduce webbing tension at collision of the occupant in a driver's seat of a vehicle. <P>SOLUTION: A first transmission part 17 is provided at a reel 4 for retracting a webbing 2 wound on the occupant and a route for transmitting driving force from an electric motor 9 to the reel 4 and a second transmission part 18 is provided between the reel 4 and a seat belt lock mechanism 10. Plastically deforming members are provided in these transmission parts and the driving force of the electric motor 9 is adjusted by the deformation and controlling by the control part 11 to control the webbing tension. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、車両衝突の危険時や急ブレーキ，急ハンドル，居眠り運転などの車両異常操作時等において運転席内の乗員の保護の向上を図るシートベルト巻取装置及びその巻き取り方法に関する。
【０００２】
【従来の技術】
車両の運転席内の乗員は衝突時や車両異常操作等における身体保護のためのシートベルト巻取装置により保護される。一般に使用されているシートベルト巻取装置は、衝突時等においてウエビングに張力を与え乗員の移動を拘束する構造のものであるが、乗員を効果的に保護すべく衝突や異常事態を検出し、ウエビングに張力を生じさせると共に乗員側に無理な張力が負荷されて乗員にダメージを与えることのないように種々の工夫がされているシートベルト巻取装置がある。例えば、衝突の可能性に応じた衝突予知信号を出力して運転席やその他の乗員に巻回されているシートベルト（ウエビング）の張力を調整したりエアバック装置を作動させるもの（特許文献１及び特許文献２参照）がある。
【０００３】
【特許文献１】
特開２００１−１１４０６９（図１，図４，図６参照）
【特許文献２】
特開２００１−１６３１８５（図１，図４参照）
【０００４】
【発明が解決しようとする課題】
特許文献１の特開２００１−１１４０６９の「シートベルトシステム」及び特許文献２の特開２００１−１６３１８５の「シートベルト装置」は衝突予知信号により車両の衝突を検出し、ウエビングに張力を与えると共に張力制御手段（ＥＡ機構等）により張力調整を行うと共にエアバックを展開して乗員の安全保護を図るようにしているが、次のような問題点がある。即ち、これ等の文献の図４や図２等において、直流モータでウエビングを巻き取っている最中に車両の衝突等によりウエビングに慣性力等による大きな力が作用し、ウエビングが引き出されるとウエビングの張力はリールからリールシャフト，プーリ，ベルト等を介して直流モータ側に伝達される。このため、ウエビングを巻き取る方向に回転力が生じている直流モータに逆方向の力が作用し、結果としてベルト等に大きな力が加わり、ベルトの内歯の破損やベルト切断等が生じ直流モータの回転力がウエビング側に伝達されなくなる恐れがある。以上の現象は衝突検出部でも検出できない軽い衝突（低速度で障害物に衝突する場合等）時に発生する。この場合でもプリテンショナの作動によるウエビングの張力上昇は抑えられるが、前記のように直流モータの駆動によるウエビング張力の上昇とこれと同時に生ずる衝突による慣性力による乗員の前方への移動によってウエビングに引き出し方向の力が作用し、ベルト切断等の問題点が発生する。仮りにベルト切断が発生した場合はその修理が完了まで直流モータによるウエビングの張力を上昇させることが出来なくなる。また、特許文献２に開示しているように、このシートベルト装置にはＥＡ（エネルギ吸収）機構が設けており、ウエビングに所定以上の張力が加わるとＥＡ機構が作動し、乗員がシートベルトから受ける力を所定以上にならないように制限して乗員を保護するが、このＥＡ機構による制限力は衝突時の衝撃の大小に拘らず一定であり、多種の衝突現象にすべて対応することが出来ない問題点があった。
【０００５】
本発明は、以上の問題点の解決や事情を考慮して発明されたものであり、電動モータとウエビングとの間に伝達部を設けてこの伝達部を変形させて無理な力の発生を抑制すると共に、電動モータとウエビングとの間やリールとシートベルトロック機構との間に伝達部を設け、この合成変形によって各種の衝突や異常現象に対応してウエビングの張力の制限を行い乗員の安全保護の確実化を図るシートベルト巻取装置及びその巻き取り方法を提供することを目的としている。
【０００６】
【課題を解決するための手段】
本発明は、以上の目的を達成するために、請求項１に記載の発明は、車両の運転席内の乗員に巻回されているウエビングと、該ウエビングのリールを正逆転駆動する電動モータとを備えるシートベルト巻取装置であって、前記電動モータと前記リールとの間に介設される第１の伝達部に加わる力が第１の所定値を超えた場合に変形する第１の変形機構部を設けることを特徴としている。この第１の変形機構部を設けることにより第１の所定値を超えた力が作用するとこの第１の変形機構部が変形しそれ以上の力の作用を抑制しウエビング張力の上昇を拘束することができる。
【０００７】
また、請求項２に記載の発明は、車両の運転席内の乗員に巻回されているウエビングと、該ウエビングのリールを正逆転駆動する電動モータと、異常時において前記ウエビングの引き出しを拘束するシートベルトロック機構部とを備えるシートベルト巻取装置であって、前記電動モータと前記リールとの間に介設される第１の伝達部に加わる力が第１の所定値を超えた場合に変形する第１の変形機構部と、前記リールと前記シートベルトロック機構部との間に介設される第２の伝達部に加わる力が第２の所定値を超えた場合に変形する第２の変形機構部を設けることを特徴としている。前記の第１の変形機構部の他に第２の変形機構部を設けることにより、ウエビングに作用する力の大きさに対応して夫々の変形機構部が変形し、この合成変形により乗員のより安全な保護を図ることができる。
【０００８】
また、請求項３のに記載の発明は、第１の変形機構部及び第２の変形機構部は、これ等に作用する力が前記第１の所定値及び第２の所定値以上になると、その一部又は全部が変形することを特徴としている。第１の変形機構部や第２の変形機構部がこれ等に作用する所定値の力に対応して一部又は全部変形しウエビング等に作用する張力の微妙な調整を行い乗員の安全保護の確実化が図られる。
【０００９】
また、請求項４に記載の発明は、前記第１の所定値が、前記ウエビングの張力で２００Ｎ以上２ｋＮ以下であることを特徴としている。所定値を以上のように決めることにより軽い衝撃時に対応することができる。
【００１０】
また、請求項５に記載の発明は、前記第２の所定値が、前記ウエビングの張力で２ｋＮ以上８ｋＮ以下であることを特徴としている。所定値を以上のように決めることにより大きな衝突時に対応することができる。
【００１１】
また、請求項６に記載の発明は、前記第１の変形機構部及び第２の変形機構部が、塑性変形部材を有するものからなることを特徴としている。夫々の変形機構部を塑性変形可能な部材から構成し、変形の確実化を図るようにしている。
【００１２】
また、請求項７に記載の発明は、前記第１の変形機構部及び／又は前記第２の変形機構部が、第１の部材と第２の部材との間に架設される又は前記第１の部材又は第２の部材のいずれかと一体的に形成される塑性変形可能な１個又は複数個の塑性変形部材を備えるものからなることを特徴としている。夫々の変形機構部として第１の部材と第２の部材間に架設させる塑性変形部材を採用し、この変形によって各部に伝達される力の抑制緩和を図るようにしている。
【００１３】
また、請求項８に記載の発明は、前記第１の部材及び第２の部材には凹穴部が形成され、前記塑性変形部材が前記凹穴部に係合する係合部を有するロッド状部材からなることを特徴としている。両端に係合部を形成しこれを第１の部材及び第２の部材の凹穴部に嵌合させることによりその中間部のロッド状部材の変形の確実化を図るようにしている。
【００１４】
また、請求項９に記載の発明は、前記ロッド状部材が、前記第１の部材又は第２の部材と一体構造に形成されることを特徴としている。一端側の係合部の替りに第１の部材又は第２の部材そのものを用いてこれ等のいずれかの部材にロッド状部材を一体的に形成せしめることにより塑性変形部材の単純化を図りコスト低減を図るようにしている。
【００１５】
また、請求項１０に記載の発明は、前記第１の部材及び第２の部材には互いに嵌合する凸部及び凹部が形成されることを特徴としている。凸部と凹部の形成により、第１の部材と第２の部材の位置決めを図り、第１の部材と第２の部材の組立性の向上を図るようにしていると共に塑性変形部材に有効に力が作用するようにしている。
【００１６】
また、請求項１１に記載の発明は、前記凸部が第１の部材又は第２の部材の端面に突出して形成されるせん断ピンからなり、前記凹部が前記せん断ピンの嵌り込む孔からなることを特徴としている。せん断ピンと孔の嵌合により第１の部材と第２の部材の初期位置決めができると共に外力作用時にはせん断ピンが破断し、塑性変形部材のロッド状部材にのみ力が作用し変形させるようにしている。
【００１７】
また、請求項１２に記載の発明は、前記第１の部材又は第２の部材のいずれかに形成される前記凸部は、前記第１の部材又は第２の部材の端面から膨出する軸受体からなり、前記第２の部材又は第１の部材には、前記軸受体の嵌合する軸受穴が凹部として形成されることを特徴としている。軸受体と軸受穴に嵌め込むことにより第１の部材と第２の部材との同一軸上に沿う位置決めを確実にし、ロッド状部材の確実な変形を可能にしている。
【００１８】
また、請求項１３に記載の発明は、前記軸受体の外周にはリング部材が嵌着され、前記軸受穴は前記リング部材が滑動可能な寸法に形成されることを特徴としている。軸受体にリング部材を嵌着することにより軸受体と軸受穴との滑り機能の向上を図り、第１の部材と第２の部材との同一軸上に沿う位置決めの確実化とロッド状部材の変形機能の向上を図るようにしている。
【００１９】
また、請求項１４に記載の発明は、前記塑性変形部材が、その一端部に膨出した引っ掛け部と該引っ掛け部から他端部に向かって軸線に沿って伸延するロッド体とを一体的に形成したものからなり、前記第１の部材又は第２の部材には、前記引っ掛け部が嵌着される嵌合孔と前記ロッド体を貫通すべく前記嵌合孔に連通して形成される貫通孔が形成され、前記第２の部材又は第１の部材には、前記ロッド体の挿入される適宜深さの保持穴が形成され、前記嵌合孔及び貫通孔の形成される第１の部材又は第２の部材の前記貫通孔の開口側には前記貫通孔に連通し前記ロッド体の直径よりも大きい深さの円周溝が形成されることを特徴としている。塑性変形部材を以上のような構造にすることにより微妙な形態の変形を可能にしている。
【００２０】
また、請求項１５に記載の発明は、前記塑性変形部材が複数個配設される場合において、前記塑性変形部材の形状が夫々相違することを特徴としている。塑性変形部材を複数個設けてその形状（例えば、全長）を変えることにより急激な変形発生の防止を図り、急激な変形荷重の落ち込みを防止している。
【００２１】
また、請求項１６に記載の発明は、前記第１の部材又は第２の部材に形成される前記保持穴は、その入口側に開放端側に向かってひらき傾斜する傾斜面からなる除変部を形成することを特徴としている。除変部を設けることにより急激な荷重の変動を改善し塑性変形部材の変形の除変化を図っている。
【００２２】
また、請求項１７に記載の発明は、前記請求項１乃至１６に示すシートベルト巻取装置におけるウエビングの巻き取り方法であって、該巻き取り方法は、まずウエビングの装着の有無を検出する第１の手順と、装着有りの場合に衝突の可能性の有無を検出する第２の手順と、衝突の可能性有りの場合に相対速度に応じて巻き取り駆動力を加減する処理を行う第３の手順と、加減された巻き取り駆動力によりウエビングの巻き取り駆動を行う第４の手順と、所定時間経過したか否かを検出する第５の手順とからなり、前記第１の手順における装着無しの場合及び第２の手順における衝突の可能性無しの場合には電動モータの駆動停止が行われ、前記第５の手順において経過しない場合は第４の手順と第５の手順との間に戻り、経過した場合には電動モータの駆動停止が行われることを特徴としている。以上の巻き取り方法により、相対速度に応じた巻き取りを行うことができ、変化に対応した巻き取り動作を確実に行わせることができる。
【００２３】
また、請求項１８に記載の発明は、障害物と車両との相対速度が低い場合には電動モータの巻き取り駆動力を小さくし、相対速度が高い場合には電動モータの巻き取り駆動力を大きくすることを特徴としている。相対速度に対応して電動モータの駆動力を調整し、巻き取り夫々の伝達機構部の変形の確実化と電動モータの保護を図っている。
【００２４】
【発明の実施の形態】
以下、本発明のシートベルト巻取装置及びその巻き取り方法の実施の形態を図面に基づいて説明する。図１に車両の運転席３８における乗員３９に巻回されているウエビング２とシートベルト巻取装置１を示す。シートベルト巻取装置１はウエビング２を巻き取ったり、衝突時や異常発生時に乗員３９を座席４０側に拘束する構造のものからなる。ウエビング２はシートベルト巻取装置１からスルーアンカ４１を介して折り返され、タングプレート４２やバックル４３を介し座席４０を載置する床面４４側に固定される。また、ウエビング２はタングプレート４２で折り返されてアンカ４５により床面４４側に固定される。なお、乗員３９の前方にはエアバッグ装置４６が配置されている。
【００２５】
図２はシートベルト巻取装置１の概要構造を示すものである。フレーム３にはウエビング２を巻回するリール４、リール４を回転するためのリールシャフト５、外歯を外周に設けたプーリ６、これに巻回されるベルト７、ベルト７に噛合するプーリ８等が収納されている。また、フレーム３には電動モータ９やシートベルトロック機構１０等が固定されている。また、電動モータ９やシートベルトロック機構部１０は各種の入力信号により動作する制御部１１により制御される。また、本発明に直接関係ないがリールシャフト５にはプリテンショナ１３や巻き取りばね１４やポテンショメータ１５等が設けられている。また、リール４内にはエネルギ吸収機構部１６が設けられている。以上の構造により電動モータ９の回転力はプーリ８、ベルト７、プーリ６を介してリールシャフト５に伝えられウエビング２を巻き取るリール４を駆動する。また、電動モータ９は駆動停止時に空転可能であり、駆動停止状態では巻き取りばねによりリール４はウエビング２を巻き取り付勢している。
【００２６】
制御部１１はマイクロコンピュータシステムによって構成され、図３の回路ブロックに示すように、タングプレート４２がバックル４３に係止されたことを検出するバックルスイッチからの信号が入力され、更に衝突予知や衝突検出信号や急ブレーキ，急ハンドル，居眠り運転等が生じた場合に乗員保護のために必要な入力信号が供給される入力インタフェースと、制御プログラムを保持するＲＯＭや電動モータやシートベルトロック機構部等を動作制御を行うためのＲＡＭやＣＰＵと、ＣＰＵからの動作指令を出力する出力インタフェースと、これにより動作される駆動回路等とからなる。駆動回路からの出力指令により、例えば、図２に示す電動モータ９やシートベルトロック機構部１０や電磁アクチュエータ１０ａ及びその他の装置等の制御が行われる。
【００２７】
シートベルトロック機構部１０は前記の特許文献１及び２にその構造が詳しく記載されているが、概略次のような機能を有するものからなる。即ち、シートベルトロック機構部はリール４の機械的ロック機構やシートベルト加速度感知手段（ＷＳＩ）や車両減速度感知手段（ＶＳＩ）と電磁アクチュエータ１０ａ等を有するものからなる。ＶＳＩは車両に所定の減速度が作用したときウエビング２の引き出しをロックする機能を有し、ＷＳＩはウエビング２が所定の加速度で引き出されたときにウエビング２の引き出しをロックする機能を有するものからなる。また、電磁アクチュエータ１０ａは指令信号に応答してＶＳＩを強制的に作動させる機能を有するものからなる。なお、シートベルトロック機構部１０はウエビング２の前記のＶＳＩが作動してロック状態にあっても電動モータ９によるウエビング２の巻取りが可能な機構が設けられている。
【００２８】
図２に示すように、本発明の第１の伝達部１７と第２の伝達部１８とはシートベルト巻取装置１のリール４の駆動系の適宜の場所に配置されてもよいが、本実施の形態では図示のように、第１の伝達部１７をリール４とプーリ６との間の場所に配置し、第２の伝達部１８をリール４とシートベルトロック機構部１０との間に配置する場合について説明する。なお、以下の説明では第１の伝達部１７と第２の伝達部１８とは基本的構造において同一であり、以下では第１の伝達部１７についての構造のみを説明とし第２の伝達部１８についての構造説明は省略する。なお、第１の伝達部１７と第２の伝達部１８の具体的構造としては第１の変形機構部１９及び第２の変形機構部２０とし、以下、第１の変形機構部１９に関する種々の実施の形態について説明する。
【００２９】
図４は第１の変形機構部１９の１つの実施の形態の第１の変形機構部１９ａを示すものである。本実施の形態では第１の部材をプーリ６とし、第２の部材をリール４とする。また、第１の部材（プーリ６）と第２の部材（リール４）とは同一軸上に相対向して配置され、その間には塑性変形部材２１が架設される。本実施の形態では塑性変形部材２１は両端に係合部２２を有し、その間をロッド部材２３で一体的に連結する構造のものからなる。なお、係合部２２は第１の部材と第２の部材の凹穴部２４及び２５に係着できる形状のものであれば任意形状のものでよい。また、塑性変形部材２１は第１の変形機構部１９では第１の所定値の張力によりその一部又は全部が塑性変形するものからなり、第２の変形機構部２０では第２の所定値の張力により一部又は全部が塑性変形するものからなる。また、第１の所定値はウエビング張力で２００Ｎ以上２ｋＮ以下のものが一例として採用され、第２の所定値は第１の所定値より大きい２ｋＮ以上８ｋＮ以下のものが一例として採用される。また、第１の変形機構部１９は前記の第１の所定値以上の張力が作用した場合には大きく変形し、電動モータ９からの所定の荷重伝達機能がなくなる形態に変形する。図５は図４に示した第１の変形機構部１９ａの組み上り状態を示す部分断面図である。図示のように、塑性変形部材２１はその係合部２２，２２をプーリ６やリール４の凹穴部２４，２５内に嵌着した状態で取り付けられ、両者はロッド部材２３のみにより電動モータ９からの回転力を伝達する形状のものからなる。以上の構造により第１の所定値の範囲の張力が作用するとロッド状部材２１の部分が変形し、電動モータ９とリール４との間の駆動力の調整が図られる。これにより、ウエビング２に引き出し力が作用しても第１の変形機構部２１が変形し、駆動系への無理な力の作用が緩和される。
【００３０】
図６は別の第１の変形機構部１９ｂを示す。第２の部材のリール４のプーリ６側の端面には凸部の１つのせん断ピン２６が突出して設けられている。また、第１の部材のプーリ６にはせん断ピン２６の嵌り込む凹部の１つである孔２７が穿孔されている。このせん断ピン２６を孔２７に嵌め込むことによりリール４とプーリ６との位置決めが行われるが、このせん断ピン２６は第１の所定値の張力の作用によりせん断されるものからなる。また、図３，図４において説明した塑性変形部材２１がリール４とプーリ６との間に架設される。以上により、初期位置決めされた状態で（ウエビング２）の変形作用が行われ、確実な変形が行われる。
【００３１】
図７は別の第１の変形機構部１９ｃを示す。図示のように、プーリ６のリール４側の端面には凸部の１つである軸受体２８が膨出して形成される。なお、この軸受体２８は円筒体からなる。一方、リール４のプーリ６側の端面には軸受体２８の嵌合する凹部としての嵌合穴２９が形成される。また、前記とほぼ同一構造の塑性変形部材２１がプーリ６とリール４との間に架設される。軸受体２８と軸受穴２９とを嵌合させることにより第１の部材と第２の部材との同心度を保持することができる。なお、この実施の形態では第１の所定値の張力の作用時には軸受体２８が軸受穴２９に案内されて回動する。
【００３２】
図８の第１の変形機構部１９ｄは図６の第１の変形機構部１９ｃの軸受体２８の外周にリング部材３０を嵌着したものであり、その他の構造は図６のものとほぼ同一である。このリング部材３０を用いることにより軸受体２８側と軸受穴２９との間の滑動が円滑に行われ、塑性変形部材２１の変形がより効果的に行われる。なお、リング部材３０は滑り部材、例えば樹脂性リング等とからなる。
【００３３】
図９は別の第１の変形機構部１９ｅを示す。この場合、塑性変形部材２１ｅは図示のように一端部に膨径の引っ掛け部３１を形成し他端部に向かって伸延するロッド体３２を有するボルト状のものからなる。なお、このロッド体３２は小径のものからなり、例えば針金からなる。プーリ６には引っ掛け部３１の嵌り込み嵌合孔３３とロッド体３２の貫通する貫通孔３４が形成される。また、貫通孔３４のリール４側の開口端面には図９に示すように円周溝３５が形成される。なお、円周溝３５の深さｈはロッド体２１ｅの直径よりも深いものからなる。一方、リール４側のプーリ６側の端面にはロッド体２１の挿入される保持穴３６が設けられている。
【００３４】
図１１，１２は図９，図１０に示した第１の変形機構部１９ｅの組み付け構造を示すものである。この場合、図示のようにプーリ６とリール４とは同一軸上に相対向して配置されその相対向する面は当接又は殆ど接触する位置関係に配置される。塑性変形部材２１ｅはその引っ掛け部３１を嵌合孔３３に嵌め込んだ形態でプーリ４側に保持され、伸延しているロッド体３２をリール４の保持穴３６に挿入した状態で連結される。
【００３５】
図１３は塑性変形部材２１ｅがしごかれて変形している状態を示す。即ち、プーリ６とリール４とは塑性変形部材２１ｅの図示のような変形により同一軸上に保持されながら回転方向に位相ズレが生じる。即ち、塑性変形部材２１ｅは円周溝３５に沿って案内されながら、保持穴３６出口にてしごかれる。図１４（ａ），（ｂ），（ｃ）は塑性変形部材２１ｅのしごき変形の進行状態を示すものであり、図１４（ｃ）には塑性変形部材２１ｅが大きく変形し保持穴３６からもう少しで抜け出るような状態が示されている。
【００３６】
図１５は以上の問題点を解決するための１つの実施の形態である。このものは図示のように保持穴３６のその端面に開放端側に向かってひらき傾斜する傾斜向きである除変部３７を形成する。これにより、ロッド体３２の曲がり角が無理なく徐々に変化し、曲げ難しさが改善され円滑な変形が行われる。
【００３７】
図１６は前記の図８等に示した複数個の塑性変形部材２１ｅを用いた場合、夫々の塑性変形部材２１ｅのロッド体３２の長さを変えた実施の形態を示す。このように、長さを変えることにより、ロッド体３２の抜け出しのタイミングに時間差が生じ、急激な変形荷重落ち込みが防止される。以上は第１の伝達部１７における第１の変形機構部１９について説明したが、次に第２の伝達部１８の第２の変形機構部２０について簡単に説明する。
【００３８】
第２の変形機構部２０は図２に示すように、リール２とシートベルトロック機構部１０との間に介設されるものであり、その実施の形態としては第１の変形機構部１９とほぼ同様のものが採用される。但し第１の変形機構部１９がこれに作用する力が第１の所定値以上となるとその一部又は全部が変形する構造からなることに対し、この第２の変形機構部２０はこれに作用する力が第１の所定値より大きな第２の所定値以上になるとその一部又は全部が変形する構造からなる点において相異する。
【００３９】
第２の変形機構部２０の実施の形態を簡単に説明すると、図４乃至図８に説明した塑性変形部材２１に近似する部材を用いたものや図９乃至図１６に説明したしごき変形をする塑性変形部材２１ｅに近似する部材を用いたものが一例として上げられるが、勿論この実施の形態に限定するものではない。また、当然ながら第２の変形機構部２０は前記のように第１の変形機構部１９よりねじれ又はしごき剛性が高い形状又は材質のものが採用されることは勿論である。
【００４０】
次に、第１の伝達部１７と第２の伝達部１８を設けたシートベルト巻取装置１における巻き取り方法の一例について説明する。この場合は第１の伝達部１７と第２の伝達部１８の合成によるウエビング２の張力調整や制限が行われる。図１７のフローチャートに示すように、まず、第１の手順としてシートベルトの装着の有無が検出される（ステップ１００）。装着されている場合（ｙｅｓ）には第２の手順の衝突の可能性の有無が検出される（ステップ１０１）。装着していない場合（ｎｏ）には駆動防止（ステップ１０２）に進む。第２の手順の衝突の可能性のある場合（ｙｅｓ）には相対速度に応じて巻き取り駆動力を加減する処理が第３の手順として行われる（ステップ１０３）。衝突の可能性のない場合（ｎｏ）にはステップ１０２の駆動停止に進む。次にシートベルトの巻き取り駆動（ステップ１０４）が第４の手順として行われる。次に、第５の手順として所定時間経過したか否かが検出され（ステップ１０５）、経過しない場合（ｎｏ）はステップ１０４とステップ１０５との間に戻り、経過した場合（ｙｅｓ）には駆動停止（ステップ１０２）に進む。なお、このフローチャートの如く動作するプログラムは前記ＲＯＭ内に記憶され、所定時間毎に実行される。
【００４１】
次に、以上の巻き取り動作における第１の伝達部１７と第２の伝達部の合成変形作用とこれに伴って行われる電動モータの巻き取り駆動力の制御方法について説明する。前記のように、衝突時の衝撃力の大小により第１の伝達部１７や第２の伝達部１８が作用し、乗員等の保護が図られるが、この場合、制御部１１は電動モータ９の駆動力の調整制御を行い、第１の伝達部１７や第２の伝達部１８の作動機能の確実化を図っている。即ち、障害物との相対速度が低い場合は電動モータ９の巻き取り駆動力を小さくしウエビング２の引き出しによる電源モータ９の逆転をしやすくし、全体のエネルギ吸収荷重を下げ、障害物との相対速度が高い場合は電動モータ９の巻き取り駆動力を大きくし、ウエビング２の引き出しによる電動モータ９の逆転をしにくくして全体のエネルギ吸収荷重を上げるようにして第１の伝達部１７や第２の伝達部１８の機能の確実化を図っている。
【００４２】
以上により、本発明のシートベルト巻取装置１についての構造説明とその巻き取り方法について説明したが、第１及び第２の伝達部の配設位置やその構造については前記のものに限定するものでなく同一技術的範疇のものが適用されることは勿論である。
【００４３】
【発明の効果】
本発明のシートベルト巻取装置及びその巻き取り方法によれば、衝突時において生ずるウエビングの張力の上昇を減少させ、かつ衝撃力の大小によりウエビングの張力を調整し、かつ障害物と車両との相対速度を検出して第１の伝達部や第２の伝達部を作動させ、電動モータのコントロールも行って乗員に大きなウエビングの張力が作用せず、安全性の向上が図れる効果が上げられる。
【図面の簡単な説明】
【図１】運転席内の乗員に巻回されるウエビングとこの張力の調整を行うシートベルト巻取装置の概要構造を示す側面図である。
【図２】シートベルト巻取装置の構成図である。
【図３】制御部の概要回路ブロック図である。
【図４】第１の伝達部の第１の変形機構部の構造を説明する部分断面図である。
【図５】図４の第１の変形機構部の組み付け構造を示す部分断面図である。
【図６】第１の変形機構部の別の実施の形態を示す部分断面図である。
【図７】第１の変形機構部の別の実施の形態を示す部分断面図である。
【図８】第１の変形機構部の更に別の実施の形態を示す部分断面図である。
【図９】第１の変形機構部の他の実施の形態を示す部分断面図である。
【図１０】図９のＡ矢視の平面図である。
【図１１】図９の第１の変形機構部の組み付け形態を示す部分断面図である。
【図１２】図９の斜視図である。
【図１３】図１１に示す第１の変形機構部による塑性変形部材のしごき変形状態を示す斜視図である。
【図１４】図１１に示した第１の変形機構部の塑性変形部材のしごき変形の進行状態を示す部分断面図である。
【図１５】図８乃至図１０に示す第１の変形機構部の保持穴の開口部に設けられている除変部とその作用を説明するための部分断面図である。
【図１６】長さ寸法の異なるロッド体におけるそのしごき時における保持穴とロッド体との係合状態を示す部分断面図である。
【図１７】本発明におけるシートベルト巻取装置の巻き取り方法を説明するためのフローチャートである。
【符号の説明】
１シートベルト巻取装置
２ウエビング
４リール
９電動モータ
１０シートベルトロック機構
１０ａ電磁アクチュエータ
１１制御部
１２入力信号
１７第１の伝達部
１８第２の伝達部
１９，１９ａ，１９ｂ，１９ｃ，１９ｄ，１９ｅ第１の変形機構部
２０第２の変形機構部
２１，２１ｅ塑性変形部材
２２係合部
２３ロッド部材
２４凹穴部
２５凹穴部
２６せん断ピン
２７孔
２８軸受体（凸部）
２９軸受穴（凹部）
３０リング部材
３１引っ掛け部
３２ロッド体
３３嵌合孔
３４貫通孔
３５円周溝
３６保持穴
３７除変部
３８運転席
３９乗員[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a seat belt winding device and a winding method thereof for improving protection of an occupant in a driver's seat at the time of danger of a vehicle collision or abnormal operation of a vehicle such as sudden braking, sudden steering, and drowsy driving.
[0002]
[Prior art]
The occupant in the driver's seat of the vehicle is protected by a seat belt retractor for protecting the body in the event of a collision or abnormal operation of the vehicle. The generally used seat belt retractor has a structure that applies tension to the webbing and restrains the movement of the occupant at the time of a collision or the like, but detects a collision or an abnormal situation in order to effectively protect the occupant, There are various types of seat belt retractors in which various tensions are applied so that tension is applied to the webbing and that excessive tension is not applied to the occupant to damage the occupant. For example, a device that outputs a collision prediction signal according to the possibility of a collision to adjust the tension of a seat belt (webbing) wound around a driver's seat or other occupants or to operate an airbag device (Patent Document 1) And Patent Document 2).
[0003]
[Patent Document 1]
JP-A-2001-114069 (see FIGS. 1, 4, and 6)
[Patent Document 2]
JP-A-2001-163185 (see FIGS. 1 and 4)
[0004]
[Problems to be solved by the invention]
The "seat belt system" of JP-A-2001-114069 of Patent Document 1 and the "seat belt device" of JP-A-2001-163185 of Patent Document 2 detect a collision of a vehicle based on a collision prediction signal, and apply tension to the webbing and tension. Although the tension is adjusted by the control means (EA mechanism or the like) and the airbag is deployed to protect the occupant, there are the following problems. That is, in FIG. 4 and FIG. 2 of these documents, while the webbing is being wound by the DC motor, a large force such as an inertia force acts on the webbing due to a vehicle collision or the like, and the webbing is pulled out when the webbing is pulled out. Is transmitted from the reel to the DC motor via a reel shaft, a pulley, a belt and the like. For this reason, a reverse force acts on the DC motor in which a rotational force is generated in the direction in which the webbing is wound, and as a result, a large force is applied to the belt and the like. May not be transmitted to the webbing side. The above-mentioned phenomenon occurs at the time of a light collision that cannot be detected by the collision detection unit (such as a case of colliding with an obstacle at a low speed). In this case as well, the increase in the webbing tension due to the operation of the pretensioner is suppressed, but as described above, the webbing tension is increased by the driving of the DC motor, and simultaneously, the occupant is moved forward by the inertia force due to the collision and pulled out to the webbing. Directional force acts, causing problems such as belt cutting. If the belt is cut, the tension of the webbing by the DC motor cannot be increased until the repair is completed. Further, as disclosed in Patent Document 2, the seat belt device is provided with an EA (energy absorbing) mechanism, and when a predetermined or more tension is applied to the webbing, the EA mechanism is activated, and the occupant is moved from the seat belt. The EA mechanism protects the occupant by limiting the received force so that it does not exceed a predetermined value. There was a problem.
[0005]
SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described problems and circumstances, and a transmission unit is provided between the electric motor and the webbing, and the transmission unit is deformed to suppress generation of an excessive force. At the same time, a transmission section is provided between the electric motor and the webbing and between the reel and the seat belt lock mechanism. This combined deformation limits the tension of the webbing in response to various collisions and abnormal phenomena, and provides occupant safety. It is an object of the present invention to provide a seat belt winding device and a winding method thereof for ensuring protection.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a webbing wound around an occupant in a driver's seat of a vehicle, and an electric motor for driving a reel of the webbing to rotate forward and reverse. A first belt deformation device that deforms when a force applied to a first transmission portion provided between the electric motor and the reel exceeds a first predetermined value. It is characterized by providing a mechanism. When a force exceeding a first predetermined value is applied by providing the first deformation mechanism, the first deformation mechanism is deformed to suppress the action of the further force and restrain the rise of the webbing tension. Can be.
[0007]
According to a second aspect of the present invention, there is provided a webbing wound around an occupant in a driver's seat of a vehicle, an electric motor for driving a reel of the webbing to rotate forward and reverse, and restraining the webbing from being pulled out in an abnormal condition. A seat belt retractor including a seat belt lock mechanism, wherein a force applied to a first transmission unit provided between the electric motor and the reel exceeds a first predetermined value. A second deforming mechanism that is deformed when a force applied to a first deforming mechanism that deforms and a second transmission unit interposed between the reel and the seat belt lock mechanism exceeds a second predetermined value; Is provided. By providing the second deformation mechanism in addition to the first deformation mechanism, each deformation mechanism is deformed in accordance with the magnitude of the force acting on the webbing. Safe protection can be achieved.
[0008]
Further, according to the invention described in claim 3, the first deformation mechanism and the second deformation mechanism are configured such that when a force acting on them becomes equal to or more than the first predetermined value and the second predetermined value, It is characterized in that some or all of them are deformed. The first deformation mechanism and the second deformation mechanism are partially or entirely deformed in response to a predetermined value of force acting on them, and delicately adjust the tension acting on the webbing and the like to protect occupant safety. Assurance is ensured.
[0009]
The invention according to claim 4 is characterized in that the first predetermined value is not less than 200 N and not more than 2 kN in tension of the webbing. By determining the predetermined value as described above, it is possible to cope with a light impact.
[0010]
Further, the invention according to claim 5 is characterized in that the second predetermined value is not less than 2 kN and not more than 8 kN in tension of the webbing. By determining the predetermined value as described above, it is possible to cope with a large collision.
[0011]
Further, the invention according to claim 6 is characterized in that the first deformation mechanism and the second deformation mechanism have plastic deformation members. Each deformation mechanism is made of a plastically deformable member so as to ensure the deformation.
[0012]
Further, in the invention according to claim 7, the first deformation mechanism and / or the second deformation mechanism are installed between a first member and a second member, or the first deformation mechanism and / or the first deformation mechanism. And one or a plurality of plastically deformable plastically deformable members integrally formed with either the member or the second member. As each of the deformation mechanisms, a plastic deformation member erected between the first member and the second member is adopted, and the deformation transmitted to each part is suppressed and relaxed.
[0013]
The invention according to claim 8, wherein the first member and the second member are formed with a concave portion, and the plastic deformable member has an engaging portion that engages with the concave portion. It is characterized by being made of a member. Engagement portions are formed at both ends, and the engagement portions are fitted into the concave portions of the first member and the second member, thereby ensuring the deformation of the rod-shaped member at the intermediate portion.
[0014]
The invention according to claim 9 is characterized in that the rod-shaped member is formed integrally with the first member or the second member. By using the first member or the second member itself instead of the engagement portion on one end side and integrally forming a rod-shaped member on any of these members, the plastic deformation member is simplified, and the cost is reduced. We try to reduce it.
[0015]
Further, the invention according to claim 10 is characterized in that the first member and the second member are formed with a convex portion and a concave portion which are fitted to each other. The formation of the projections and the depressions positions the first member and the second member, improves the assemblability of the first member and the second member, and effectively applies a force to the plastic deformation member. Is working.
[0016]
In the invention according to claim 11, the convex portion is formed by a shear pin formed to project from an end surface of the first member or the second member, and the concave portion is formed by a hole into which the shear pin is fitted. It is characterized by. The first member and the second member can be initially positioned by fitting the shear pin and the hole, and when an external force is applied, the shear pin is broken, and a force acts only on the rod-shaped member of the plastically deformable member to deform the member. .
[0017]
According to a twelfth aspect of the present invention, in the bearing according to the first aspect, the convex portion formed on either the first member or the second member swells from an end surface of the first member or the second member. A bearing hole in which the bearing body fits is formed as a concave portion in the second member or the first member. By fitting into the bearing body and the bearing hole, the positioning of the first member and the second member along the same axis is ensured, and the rod-shaped member can be surely deformed.
[0018]
According to a thirteenth aspect of the present invention, a ring member is fitted to the outer periphery of the bearing body, and the bearing hole is formed to have a size in which the ring member can slide. By fitting the ring member to the bearing body, the sliding function between the bearing body and the bearing hole is improved, the positioning of the first member and the second member along the same axis is ensured, and the rod-shaped member is moved. The transformation function is improved.
[0019]
Further, the invention according to claim 14 is characterized in that the plastic deformation member integrally includes a hook portion bulging at one end thereof and a rod body extending along the axis from the hook portion toward the other end. The first member or the second member has a fitting hole in which the hook portion is fitted, and a through hole formed in communication with the fitting hole so as to penetrate the rod body. A hole is formed, and a holding hole having an appropriate depth into which the rod body is inserted is formed in the second member or the first member, and a first member in which the fitting hole and the through hole are formed. Alternatively, on the opening side of the through hole of the second member, a circumferential groove communicating with the through hole and having a depth greater than the diameter of the rod body is formed. By forming the plastic deformation member as described above, a delicate deformation can be achieved.
[0020]
The invention according to claim 15 is characterized in that, when a plurality of the plastic deformation members are provided, the shapes of the plastic deformation members are different from each other. By providing a plurality of plastically deformable members and changing the shape (for example, the total length) of the members, abrupt deformation is prevented from occurring, and a sharp drop in the deformation load is prevented.
[0021]
The invention according to claim 16, wherein the holding hole formed in the first member or the second member has a sloped surface which is inclined toward the open end at the entrance side. Is formed. The provision of the deforming portion improves sudden changes in load and removes the deformation of the plastic deformation member.
[0022]
According to a seventeenth aspect of the present invention, there is provided a webbing winding method in the seat belt winding device according to any one of the first to sixteenth aspects, wherein the winding method first detects whether or not the webbing is attached. The first procedure, the second procedure for detecting the possibility of collision when there is a mounting, and the third procedure for adjusting the winding driving force according to the relative speed when there is a possibility of collision. , A fourth procedure for driving the webbing to be wound by the adjusted winding drive force, and a fifth procedure for detecting whether or not a predetermined time has elapsed. When there is no collision and when there is no possibility of collision in the second procedure, the driving of the electric motor is stopped, and when the fifth procedure does not elapse, between the fourth procedure and the fifth procedure. Return and if It is characterized in that the drive stop of the movement motor is performed. With the above-described winding method, winding can be performed according to the relative speed, and the winding operation corresponding to the change can be reliably performed.
[0023]
Further, the invention according to claim 18 reduces the winding driving force of the electric motor when the relative speed between the obstacle and the vehicle is low, and decreases the winding driving force of the electric motor when the relative speed is high. It is characterized by being enlarged. The driving force of the electric motor is adjusted in accordance with the relative speed, thereby ensuring the deformation of each of the winding mechanisms and protecting the electric motor.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a seat belt winding device and a winding method thereof according to the present invention will be described with reference to the drawings. FIG. 1 shows the webbing 2 and the seatbelt winding device 1 wound around an occupant 39 in a driver's seat 38 of the vehicle. The seatbelt winding device 1 has a structure in which the webbing 2 is wound, or the occupant 39 is restrained to the seat 40 side in the event of a collision or an abnormality. The webbing 2 is folded back from the seat belt retractor 1 via a through anchor 41, and is fixed to the floor surface 44 on which the seat 40 is placed via a tongue plate 42 and a buckle 43. The webbing 2 is folded back by the tongue plate 42 and fixed to the floor surface 44 by the anchor 45. Note that an airbag device 46 is disposed in front of the occupant 39.
[0025]
FIG. 2 shows a schematic structure of the seat belt retractor 1. The frame 3 includes a reel 4 for winding the webbing 2, a reel shaft 5 for rotating the reel 4, a pulley 6 provided with external teeth on the outer periphery, a belt 7 wound around the pulley 6, and a pulley 8 meshing with the belt 7. Etc. are stored. An electric motor 9, a seat belt lock mechanism 10, and the like are fixed to the frame 3. Further, the electric motor 9 and the seat belt lock mechanism 10 are controlled by a control unit 11 which operates according to various input signals. Although not directly related to the present invention, the reel shaft 5 is provided with a pretensioner 13, a take-up spring 14, a potentiometer 15, and the like. Further, an energy absorbing mechanism 16 is provided in the reel 4. With the above structure, the rotational force of the electric motor 9 is transmitted to the reel shaft 5 via the pulley 8, the belt 7, and the pulley 6, and drives the reel 4 on which the webbing 2 is wound. The electric motor 9 can idle when the drive is stopped, and in the stopped state, the reel 4 urges the webbing 2 to be wound by the winding spring.
[0026]
The control unit 11 is configured by a microcomputer system, and receives a signal from a buckle switch for detecting that the tongue plate 42 is locked to the buckle 43 as shown in the circuit block of FIG. An input interface that supplies input signals necessary to protect the occupant in the event of a detection signal, sudden braking, sudden steering, dozing, etc., a ROM that holds a control program, an electric motor, a seat belt lock mechanism, etc. A RAM and a CPU for controlling the operation of the CPU, an output interface for outputting an operation command from the CPU, and a drive circuit and the like operated by the output interface. An output command from the drive circuit controls, for example, the electric motor 9, the seat belt lock mechanism 10, the electromagnetic actuator 10a, and other devices shown in FIG.
[0027]
Although the structure of the seat belt lock mechanism 10 is described in detail in Patent Documents 1 and 2, the seat belt lock mechanism 10 generally has the following functions. That is, the seat belt lock mechanism includes a mechanical lock mechanism for the reel 4, a seat belt acceleration sensor (WSI), a vehicle deceleration sensor (VSI), an electromagnetic actuator 10a, and the like. The VSI has a function of locking the drawer of the webbing 2 when a predetermined deceleration acts on the vehicle, and the WSI has a function of locking the drawer of the webbing 2 when the webbing 2 is drawn at a predetermined acceleration. Become. The electromagnetic actuator 10a has a function of forcibly operating the VSI in response to a command signal. The seat belt lock mechanism 10 is provided with a mechanism that allows the electric motor 9 to take up the webbing 2 even when the VSI of the webbing 2 is operated and the webbing 2 is locked.
[0028]
As shown in FIG. 2, the first transmission unit 17 and the second transmission unit 18 of the present invention may be arranged at an appropriate place in the drive system of the reel 4 of the seat belt retractor 1. In the embodiment, as illustrated, the first transmission unit 17 is disposed at a location between the reel 4 and the pulley 6, and the second transmission unit 18 is disposed between the reel 4 and the seat belt lock mechanism 10. The case of arrangement will be described. In the following description, the first transmitting unit 17 and the second transmitting unit 18 have the same basic structure, and only the structure of the first transmitting unit 17 will be described below, and the second transmitting unit 18 will be described. The description of the structure is omitted. Note that the specific structures of the first transmission unit 17 and the second transmission unit 18 are a first deformation mechanism unit 19 and a second deformation mechanism unit 20. Hereinafter, various structures related to the first deformation mechanism unit 19 will be described. An embodiment will be described.
[0029]
FIG. 4 shows a first deformation mechanism 19a of the first deformation mechanism 19 according to one embodiment. In the present embodiment, the first member is a pulley 6 and the second member is a reel 4. The first member (pulley 6) and the second member (reel 4) are disposed on the same axis so as to face each other, and a plastic deformation member 21 is provided between them. In the present embodiment, the plastic deformation member 21 has a structure in which engagement portions 22 are provided at both ends, and a portion therebetween is integrally connected by a rod member 23. The engaging portion 22 may have any shape as long as it can be engaged with the concave portions 24 and 25 of the first member and the second member. Further, the plastic deformation member 21 is made of a plastic deformation member which is partially or entirely plastically deformed by the tension of the first predetermined value in the first deformation mechanism portion 19, and is formed of the second predetermined value in the second deformation mechanism portion 20. A part or the whole is plastically deformed by the tension. The first predetermined value is, for example, a webbing tension of 200N or more and 2kN or less, and the second predetermined value is 2kN or more and 8kN or less which is larger than the first predetermined value. Further, the first deformation mechanism section 19 is greatly deformed when a tension equal to or more than the first predetermined value acts thereon, and is deformed into a form in which the predetermined load transmission function from the electric motor 9 is lost. FIG. 5 is a partial cross-sectional view showing an assembled state of the first deformation mechanism 19a shown in FIG. As shown in the drawing, the plastic deformation member 21 is attached with its engaging portions 22 and 22 fitted in the concave holes 24 and 25 of the pulley 6 and the reel 4, and both of them are connected only by the rod member 23 to the electric motor 9. Of a shape that transmits the rotational force from the motor. With the above structure, when a tension in the first predetermined range is applied, the rod-shaped member 21 is deformed, and the driving force between the electric motor 9 and the reel 4 is adjusted. As a result, even if a pull-out force acts on the webbing 2, the first deformation mechanism 21 is deformed, and the action of an unreasonable force on the drive system is reduced.
[0030]
FIG. 6 shows another first deformation mechanism 19b. One of the protrusions is provided with one shear pin 26 protruding from the end face of the second member on the pulley 6 side of the reel 4. The pulley 6 of the first member is provided with a hole 27, which is one of concave portions into which the shear pin 26 is fitted. The positioning of the reel 4 and the pulley 6 is performed by fitting the shear pin 26 into the hole 27, and the shear pin 26 is sheared by the action of a first predetermined value of tension. The plastic deformation member 21 described with reference to FIGS. 3 and 4 is installed between the reel 4 and the pulley 6. As described above, the deformation operation of the (webbing 2) is performed in the state of the initial positioning, and the deformation is reliably performed.
[0031]
FIG. 7 shows another first deformation mechanism 19c. As shown in the drawing, a bearing body 28, which is one of the protrusions, is formed to protrude from the end surface of the pulley 6 on the reel 4 side. The bearing 28 is formed of a cylindrical body. On the other hand, a fitting hole 29 is formed in the end face of the reel 4 on the pulley 6 side as a concave portion into which the bearing body 28 fits. A plastic deformation member 21 having substantially the same structure as described above is provided between the pulley 6 and the reel 4. By fitting the bearing body 28 and the bearing hole 29, the concentricity between the first member and the second member can be maintained. In this embodiment, when a first predetermined value of tension acts, the bearing body 28 is guided by the bearing hole 29 and rotates.
[0032]
The first deformation mechanism 19d in FIG. 8 is obtained by fitting a ring member 30 around the outer periphery of the bearing body 28 of the first deformation mechanism 19c in FIG. 6, and the other structure is substantially the same as that in FIG. It is. By using the ring member 30, the sliding between the bearing body 28 and the bearing hole 29 is performed smoothly, and the plastic deformation member 21 is more effectively deformed. The ring member 30 is formed of a sliding member, for example, a resin ring.
[0033]
FIG. 9 shows another first deformation mechanism 19e. In this case, as shown in the figure, the plastic deformation member 21e is formed of a bolt having a hook portion 31 having an enlarged diameter at one end and a rod 32 extending toward the other end. The rod body 32 has a small diameter, and is made of, for example, a wire. The pulley 6 is formed with a fitting hole 33 into which the hook portion 31 is fitted and a through hole 34 through which the rod body 32 penetrates. Further, a circumferential groove 35 is formed in the opening end face of the through hole 34 on the reel 4 side as shown in FIG. Note that the depth h of the circumferential groove 35 is larger than the diameter of the rod body 21e. On the other hand, a holding hole 36 into which the rod body 21 is inserted is provided on the end face of the pulley 6 on the reel 4 side.
[0034]
FIGS. 11 and 12 show an assembly structure of the first deformation mechanism 19e shown in FIGS. In this case, as shown in the drawing, the pulley 6 and the reel 4 are arranged on the same axis so as to face each other, and the faces facing each other are arranged so as to abut or almost contact each other. The plastic deformation member 21e is held on the pulley 4 side with the hook portion 31 fitted in the fitting hole 33, and connected with the extending rod body 32 inserted into the holding hole 36 of the reel 4.
[0035]
FIG. 13 shows a state in which the plastic deformation member 21e is deformed by being wrung. That is, the pulley 6 and the reel 4 undergo a phase shift in the rotation direction while being held on the same axis due to the deformation of the plastic deformation member 21e as illustrated. That is, the plastic deformation member 21e is squeezed at the outlet of the holding hole 36 while being guided along the circumferential groove 35. 14 (a), (b) and (c) show the progress of the ironing deformation of the plastic deformation member 21e. FIG. 14 (c) shows that the plastic deformation member 21e is greatly deformed and a little more from the holding hole 36. A state in which the user exits with is shown.
[0036]
FIG. 15 shows one embodiment for solving the above problems. As shown in the figure, a deformable portion 37 is formed on the end face of the holding hole 36, which is inclined toward the open end side. Thereby, the bending angle of the rod body 32 gradually changes without difficulty, the bending difficulty is improved, and smooth deformation is performed.
[0037]
FIG. 16 shows an embodiment in which the length of the rod body 32 of each of the plastically deformable members 21e is changed when the plurality of plastically deformable members 21e shown in FIG. 8 and the like are used. As described above, by changing the length, a time difference occurs in the timing at which the rod body 32 comes out, and a sharp drop in the deformation load is prevented. The first deformation mechanism 19 of the first transmission unit 17 has been described above. Next, the second deformation mechanism 20 of the second transmission unit 18 will be briefly described.
[0038]
As shown in FIG. 2, the second deformation mechanism 20 is provided between the reel 2 and the seat belt lock mechanism 10. Almost the same thing is adopted. However, while the first deformation mechanism portion 19 has a structure in which a part or the whole thereof is deformed when the force acting on the first deformation mechanism portion 19 becomes equal to or more than a first predetermined value, the second deformation mechanism portion 20 acts on this. When the applied force is equal to or more than a second predetermined value larger than the first predetermined value, a part or the whole thereof is different in that the structure is deformed.
[0039]
The embodiment of the second deformation mechanism section 20 will be briefly described. The second deformation mechanism section 20 uses a member similar to the plastic deformation member 21 described in FIGS. 4 to 8 or performs the ironing deformation described in FIGS. 9 to 16. An example using a member similar to the plastic deformation member 21e is given as an example, but is of course not limited to this embodiment. In addition, as a matter of course, the second deformation mechanism section 20 is of a shape or material having higher torsional or ironic rigidity than the first deformation mechanism section 19 as described above.
[0040]
Next, an example of a winding method in the seat belt winding device 1 provided with the first transmission unit 17 and the second transmission unit 18 will be described. In this case, the tension adjustment and restriction of the webbing 2 are performed by combining the first transmission unit 17 and the second transmission unit 18. As shown in the flowchart of FIG. 17, first, as a first procedure, the presence or absence of the seat belt is detected (step 100). If it is mounted (yes), the presence or absence of the possibility of collision in the second procedure is detected (step 101). If not mounted (no), the process proceeds to drive prevention (step 102). If there is a possibility of collision in the second procedure (yes), a process of adjusting the winding drive force according to the relative speed is performed as a third procedure (step 103). If there is no possibility of collision (no), the process proceeds to step 102 to stop driving. Next, a seat belt winding drive (step 104) is performed as a fourth procedure. Next, as a fifth procedure, it is detected whether or not a predetermined time has elapsed (step 105). If the predetermined time has not elapsed (no), the process returns to steps 104 and 105. If the predetermined time has elapsed (yes), the drive is started. Proceed to stop (step 102). A program that operates as shown in this flowchart is stored in the ROM and is executed at predetermined time intervals.
[0041]
Next, a description will be given of a combined deformation effect of the first transmission unit 17 and the second transmission unit in the above-described winding operation, and a method of controlling the winding driving force of the electric motor performed along with the combined deformation operation. As described above, depending on the magnitude of the impact force at the time of the collision, the first transmission unit 17 and the second transmission unit 18 act to protect the occupant and the like. In this case, the control unit 11 The driving force is adjusted and controlled to ensure the operation functions of the first transmission unit 17 and the second transmission unit 18. That is, when the relative speed with respect to the obstacle is low, the take-up driving force of the electric motor 9 is reduced to facilitate the reverse rotation of the power supply motor 9 by pulling out the webbing 2, lowering the overall energy absorption load, and When the relative speed is high, the take-up driving force of the electric motor 9 is increased, the reverse rotation of the electric motor 9 due to the withdrawal of the webbing 2 is prevented, and the entire energy absorbing load is increased so that the first transmission unit 17 The function of the second transmission unit 18 is ensured.
[0042]
As described above, the structure description and the winding method of the seat belt winding device 1 of the present invention have been described. However, the arrangement positions and the structures of the first and second transmission units are limited to those described above. Of course, those of the same technical category are applied.
[0043]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the seatbelt winding device and its winding method of this invention, the rise of the webbing tension which arises at the time of a collision is reduced, the webbing tension is adjusted by the magnitude of an impact force, and the obstacle and the vehicle By detecting the relative speed, the first transmission unit and the second transmission unit are operated, the electric motor is controlled, and a large webbing tension is not applied to the occupant, so that the effect of improving safety can be achieved.
[Brief description of the drawings]
FIG. 1 is a side view showing a schematic structure of a webbing wound around an occupant in a driver's seat and a seat belt retractor for adjusting the tension.
FIG. 2 is a configuration diagram of a seat belt winding device.
FIG. 3 is a schematic circuit block diagram of a control unit.
FIG. 4 is a partial cross-sectional view illustrating a structure of a first deformation mechanism of the first transmission unit.
FIG. 5 is a partial cross-sectional view showing an assembling structure of a first deformation mechanism unit in FIG. 4;
FIG. 6 is a partial cross-sectional view showing another embodiment of the first deformation mechanism.
FIG. 7 is a partial cross-sectional view showing another embodiment of the first deformation mechanism.
FIG. 8 is a partial cross-sectional view showing still another embodiment of the first deformation mechanism.
FIG. 9 is a partial cross-sectional view showing another embodiment of the first deformation mechanism.
FIG. 10 is a plan view as viewed in the direction of arrow A in FIG. 9;
FIG. 11 is a partial cross-sectional view showing an assembling mode of a first deformation mechanism unit in FIG. 9;
FIG. 12 is a perspective view of FIG. 9;
FIG. 13 is a perspective view showing an ironing deformation state of the plastic deformation member by the first deformation mechanism shown in FIG. 11;
FIG. 14 is a partial cross-sectional view showing the progress of ironing deformation of the plastic deformation member of the first deformation mechanism shown in FIG. 11;
FIG. 15 is a partial cross-sectional view for explaining a deforming portion provided in the opening of the holding hole of the first deformation mechanism shown in FIGS. 8 to 10 and its operation.
FIG. 16 is a partial cross-sectional view showing an engagement state between the holding hole and the rod body when the iron bodies of the rod bodies having different length dimensions are ironed.
FIG. 17 is a flowchart illustrating a winding method of the seatbelt winding device according to the present invention.
[Explanation of symbols]
1 Seat belt winding device
2 Webbing
4 reel
9 Electric motor
10 Seat belt lock mechanism
10a Electromagnetic actuator
11 Control part
12 Input signal
17 1st transmission part
18 Second transmission unit
19, 19a, 19b, 19c, 19d, 19e First deformation mechanism
20 Second deformation mechanism
21, 21e plastically deformable member
22 Engagement part
23 Rod member
24 Concave hole
25 Concave hole
26 Shear pin
27 holes
28 Bearing (convex)
29 Bearing hole (recess)
30 ring members
31 Hook
32 rod body
33 mating hole
34 Through hole
35 circumferential groove
36 Holding hole
37 Dividing part
38 Driver's seat
39 crew

Claims

What is claimed is: 1. A seat belt winding device comprising: a webbing wound around an occupant in a driver seat of a vehicle; A seat belt retractor, comprising: a first deformation mechanism configured to deform when a force applied to a first transmission unit provided exceeds a first predetermined value.

A seat belt winding comprising: a webbing wound around an occupant in a driver's seat of a vehicle; an electric motor for driving a reel of the webbing to rotate forward and backward; A take-off device, a first deformation mechanism portion that deforms when a force applied to a first transmission portion provided between the electric motor and the reel exceeds a first predetermined value; A second deformation mechanism is provided which is deformed when a force applied to a second transmission unit provided between the reel and the seat belt lock mechanism exceeds a second predetermined value. Seat belt winding device.

The first deformation mechanism and the second deformation mechanism are partially or entirely deformed when a force acting on them becomes equal to or more than the first predetermined value and the second predetermined value. The seat belt retractor according to claim 1 or 2, wherein:

The seat belt retractor according to claim 1, wherein the first predetermined value is not less than 200 N and not more than 2 kN in tension of the webbing.

The seat belt retractor according to claim 2, wherein the second predetermined value is not less than 2 kN and not more than 8 kN in tension of the webbing.

The seat belt retractor according to claim 1, wherein the first deformation mechanism and the second deformation mechanism include a plastic deformation member.

The first deformation mechanism and / or the second deformation mechanism are bridged between a first member and a second member which are disposed on the same axis and are opposed to each other; The seat belt according to claim 1 or 2, comprising one or more plastically deformable plastically deformable members formed integrally with either the first member or the second member. Winding device.

8. The method according to claim 7, wherein the first member and the second member have a concave portion formed therein, and the plastic deformation member is a rod-shaped member having an engaging portion that engages with the concave portion. 3. The seat belt winding device according to 1.

The seat belt retractor according to claim 7, wherein the rod-shaped member is formed integrally with the first member or the second member.

The seat belt retractor according to claim 7, wherein the first member and the second member are formed with a convex portion and a concave portion that fit with each other.

The sheet according to claim 10, wherein the convex portion is formed of a shear pin formed to project from an end surface of the first member or the second member, and the concave portion is formed of a hole into which the shear pin is fitted. Belt winding device.

The convex portion formed on either the first member or the second member is formed of a bearing body swelling from an end surface of the first member or the second member, and the second member or the second The seat belt retractor according to claim 10, wherein a bearing hole in which the bearing body is fitted is formed as a concave portion in the first member.

13. The seat belt retractor according to claim 12, wherein a ring member is fitted around an outer periphery of the bearing body, and the bearing hole is formed to have a size in which the ring member can slide.

The first member is formed by integrally forming a hook portion bulging at one end thereof and a rod body extending along the axis from the hook portion toward the other end; Alternatively, the second member has a fitting hole in which the hook portion is fitted, and a through hole formed in communication with the fitting hole so as to penetrate the rod body, and the second member or The first member has a holding hole of an appropriate depth into which the rod body is inserted, and the opening of the through hole of the first member or the second member in which the fitting hole and the through hole are formed. The seat belt retractor according to claim 7, wherein a circumferential groove having a depth greater than a diameter of the rod body is formed on a side of the seat belt communicating with the through hole.

15. The seat belt retractor according to claim 14, wherein when a plurality of the plastic deformation members are provided, the shapes thereof are different from each other.

The said holding hole formed in the said 1st member or the 2nd member forms the deformation | transformation part which consists of an inclined surface which opens and inclines toward the open end side at the entrance side. Or the seat belt retractor according to item 15.

A webbing winding method in the seat belt winding device according to any one of claims 1 to 16, wherein the winding method includes: a first step of detecting whether the webbing is attached; A second procedure for detecting whether or not there is a possibility, a third procedure for performing a process of adjusting the winding driving force in accordance with the relative speed when there is a possibility of a collision, and an adjusted winding driving force. And a fifth procedure for detecting whether or not a predetermined time has elapsed. The fourth procedure for detecting whether or not a predetermined time has elapsed. If there is no possibility, the drive of the electric motor is stopped. If the fifth procedure does not elapse, the process returns to between the fourth and fifth procedures. The suspension will take place Winding method of the seat belt retractor according to claim.

18. The winding driving force of the electric motor is reduced when the relative speed between the obstacle and the vehicle is low, and the winding driving force of the electric motor is increased when the relative speed is high. The winding method of the seat belt winding device according to the above.