JP4023212B2

JP4023212B2 - Air bag device for knee protection

Info

Publication number: JP4023212B2
Application number: JP2002141578A
Authority: JP
Inventors: 千春戸谷; 光安藤; 武司細川; 博幸田嶌
Original assignee: Toyoda Gosei Co Ltd
Current assignee: Toyoda Gosei Co Ltd
Priority date: 2001-05-21
Filing date: 2002-05-16
Publication date: 2007-12-19
Anticipated expiration: 2022-05-16
Also published as: JP2003040069A

Description

【０００１】
【発明の属する技術分野】
本発明は、膨張用ガスを流入させて展開膨張するエアバッグが、着座した乗員の膝を保護可能な膝保護用エアバッグ装置に関する。
【０００２】
【従来の技術とその課題】
従来、運転者等を含めた乗員の膝を保護する膝保護用エアバッグ装置としては、特開平９−１２３８６２号公報に開示されるように、乗員の膝を保護するためにステアリングコラムの下方位置に配置されて、作動時にコラムカバー上部の下面側に向かって展開膨張するエアバッグと、エアバッグに膨張用ガスを供給するインフレーターと、エアバッグとインフレーターとを収納するケースと、収納されたエアバッグを突出可能に覆うエアバッグカバーと、を備えて構成されるものがあった。
【０００３】
このような構成のエアバッグ装置では、着座した乗員の前方側に配置される板状部材、例えば、ニーパネル（ニーボルスターともいう）に、ケース等を配設させることが考えられる。
【０００４】
なお、ニーパネルは、ニーパネルの車両前方側に配置された衝撃エネルギー吸収体に連結されて、着座した乗員の前方側を広く覆うように配置されている。そして、このニーパネルは、車両の前面衝突の際、前方移動する乗員の膝を受け止め、膝とともに車両前方側に移動して、車両前方側に配置された衝撃エネルギー吸収体を変形させることにより、前方移動する膝の衝撃を緩和するように、作用するものである。
【０００５】
そして、このようなニーパネル等の板状部材にエアバッグやインフレーターを収納する場合、折り畳んだエアバッグを覆うエアバッグカバーも、その板状部材に取り付ける必要が生ずる。
【０００６】
このエアバッグカバーは、外観意匠を低下させないように、ニーパネル等の板状部材の車両後方側の面を広く覆うとともに、折り畳まれたエアバッグを覆って膨張時のエアバッグに押されて開く扉部を、別体で配設するのではなく、一体的に形成することが望ましく、このような構成では、周囲に破断予定部を設けて、扉部をエアバッグカバー自体と一体的に形成することとなる。
【０００７】
しかし、一体化させた扉部を有するエアバッグカバーを、上記の板状部材に取り付ける場合には、円滑に、破断予定部を破断させて扉部を開かせることに、課題が生ずる。
【０００８】
本発明は、上記の課題に鑑み、一体化させた扉部を有するエアバッグカバーを、着座した乗員の膝の前方側に配置された板状部材に対して、取り付けても、エアバッグに押された扉部を、円滑に開かせることができる膝保護用エアバッグ装置を提供することを目的とする。
【０００９】
【課題を解決するための手段】
本発明に係る膝保護用エアバッグ装置は、着座した乗員の膝の前方側に配置された板状部材に、折り畳まれた膝保護用のエアバッグ及び該エアバッグに膨張用ガスを供給するインフレーターを、収納させるとともに、収納されたエアバッグを突出可能に覆うエアバッグカバーを、取り付けて、構成される膝保護用エアバッグ装置であって、
前記板状部材が、
車両後方側を開口させて、前記エアバッグと前記インフレーターとを収納する有底の箱形状の収納部と、
該収納部の開口の周縁から延びるように形成される板状とされて、車両のボディ側に取り付けられるとともに、膨張完了時の前記エアバッグの車両前方側を支持可能とされる本体部と、
から、構成され、
前記エアバッグカバーが、合成樹脂製とされて、
前記収納部の開口を覆うとともに、膨張時の前記エアバッグに押されて、周縁の薄肉の破断予定部を破断させて開く扉部と、
前記扉部の周囲に配置され、開き時の前記扉部の回転中心となるヒンジ部と、
前記破断予定部及び前記ヒンジ部を間に介在させ、前記扉部の周囲に配置されて、前記板状部材における前記収納部の周縁の車両後方側を覆う一般部と、
を備えて構成されるとともに、
前記一般部における前記収納部の開口周縁の近傍の複数箇所に、前記収納部に取り付けられる取付片を、配設させて構成され、
前記板状部材において、前記本体部における前記収納部の開口の周縁となる部位に、前記取付片を挿通可能な複数の貫通孔が、形成されていることを特徴とする。
【００１０】
そして、前記エアバッグカバーの各取付片は、それぞれ、係止孔を備えて構成し、前記収納部には、前記係止孔に挿入させて前記各取付片を係止可能な複数のフックを設けて構成することが望ましい。
また、前記フックは、前記収納部の開口から離れる側に反転させるようにして配置されるとともに前記係止孔内に挿入される係止鉤部と、前記取付片を前記収納部から離れるように弾性変形可能に案内するガイド面と、を備える構成とされ、
前記取付片は、前記貫通孔に挿入される際に、前記ガイド面に干渉して、前記収納部から離れるように弾性変形し、前記係止孔が前記係止鉤部の位置に配置された際に、復元して、前記係止孔内に前記係止鉤部を挿入させる構成とすることが望ましい。
さらに、前記板状部材は、板金製とすることが望ましい。
さらにまた、前記板状部材は、前記収納部の開口の周縁から延びるように形成される平板状の本体部を備える構成とされ、
該本体部の周縁に、前記板状部材を車両のボディ側に取り付ける取付片部が、配設されている構成とすることが望ましい。
さらにまた、前記本体部は、前記エアバッグカバーの一般部を支持可能な支持部を備えている構成とすることが望ましい。
【００１１】
【発明の効果】
本発明に係る膝保護用エアバッグ装置では、インフレーターが作動して、インフレーターから膨張用ガスが吐出されれば、その膨張用ガスにより、エアバッグが膨張する。そして、エアバッグは、エアバッグカバーの扉部を押し、破断予定部を破断させて、ヒンジ部を回転中心として扉部を開かせ、その結果、収納部の開口から車両後方側に突出し、乗員の膝を保護可能に、大きく展開膨張することとなる。
【００１２】
このエアバッグの展開膨張時、エアバッグカバーは、一般部における収納部開口周縁の近傍の複数箇所に配設させた取付片を、板状部材を貫通させて収納部に取り付けているため、収納部の開口周縁近傍における一般部の破断予定部やヒンジ部の部位が、収納部に対して移動し難く、エアバッグの押圧力が的確に破断予定部に作用して、破断予定部が円滑に破断する。また、開き時の回転中心となるヒンジ部も、収納部に対して移動し難く、扉部の開き動作を安定させることができる。その結果、エアバッグカバーを熱可塑性エラストマー等の合成樹脂から形成しても、エアバッグに押された扉部は、円滑に、開くこととなる。
【００１３】
したがって、本発明に係る膝保護用エアバッグ装置では、一体化させた扉部を有するエアバッグカバーを、着座した乗員の膝の前方側に配置された板状部材に対して、取り付けても、エアバッグに押された扉部を、円滑に開かせることができる。
【００１４】
また、エアバッグカバーの各取付片は、板状部材における収納部の開口周縁に貫通させるだけであって、板状部材は、外形形状が小さくならないことから、エアバッグの非膨張状態で、乗員の膝が干渉してきても、広い面積で、膝を受けることが可能となる。勿論、この態様は、板状部材が膨張を完了させたエアバッグの車両前方側を支持できることにもなり、展開膨張を完了させたエアバッグは、板状部材によって、安定して支持されることとなる。
【００１５】
さらに、本発明に係る膝保護用エアバッグ装置では、エアバッグとインフレーターとを板状部材に設けた収納部に収納させ、さらに、折り畳まれたエアバッグを覆う扉部を有し、かつ、板状部材の収納部開口の周縁における車両後方側を覆う一般部を有したエアバッグカバーを、板状部材に取り付ける構成である。すなわち、エアバッグ、インフレーター、エアバッグカバー、及び、板状部材、を予め一体化することができる構成である。そのため、エアバッグ、インフレーター、エアバッグカバー、及び、板状部材、を予め一体化させておけば、アセンブリー化した状態で、エアバッグ等を運搬・保管等することができ、車両に取り付けるまでの各部材の取扱性が容易となる。
【００１６】
そして、請求項２に記載したように構成されている場合には、収納部の各フックを、エアバッグカバーの各取付片の係止孔に、挿入させ、各フックによって取付片を係止すれば、取付片の収納部への取付を完了させることができるため、エアバッグカバーの板状部材への取付工数・コストを低減させることができる。
【００１７】
【発明の実施の形態】
以下、本発明の一実施形態を図面に基づいて説明する。
【００１８】
実施形態の膝保護用エアバッグ装置Ｓは、図１〜４に示すように、乗員Ｍとしての運転者ＭＤの膝Ｋを保護できるように、運転者ＭＤの車両前方側であるステアリングコラム７の下方に配設されている。
【００１９】
なお、本明細書における上下、左右、及び、前後は、膝保護用エアバッグ装置Ｓを車両に搭載させた際の車両の上下・左右・前後に対応するものである。
【００２０】
ステアリングコラム７は、図１に示すように、ステアリングホイール６に連結されるメインシャフト８と、メインシャフト８の周囲を覆うコラムチューブ９と、を備えて構成され、メインシャフト８とコラムチューブ９との間には、ステアリングホイール６のリング面の角度を調整可能な図示しないチルト機構や、ステアリングホイール６をシャフトの軸方向に移動させて停止可能な図示しないテレスコピック機構等が、配設されている。
【００２１】
コラムカバー１０は、略四角筒形状等の合成樹脂製として、ステアリングホイール６の下方のステアリングコラム７を覆うように、ステアリングコラム７の軸方向に沿って配設されている。即ち、コラムカバー１０は、車両前方側を下方に配置させて、車両後方側を上方に配置させるように、後上がりに傾斜して配設されている。そして、コラムカバー１０におけるインストルメントパネル（以下、インパネとする）１２から突出する部位の下面１０ａは、略長方形形状とし、車両前後方向で、後上がりの曲面状に形成されている。
【００２２】
膝保護用エアバッグ装置Ｓは、折り畳まれたエアバッグ４６、エアバッグ４６に膨張用ガスを供給するインフレーター４１、折り畳まれたエアバッグ４６を覆うエアバッグカバー３０、及び、板状部材としてのニーパネル１６、を備えて構成されている。そして、実施形態のエアバッグ装置Ｓでは、エアバッグ４６、インフレーター４１、及び、エアバッグカバー３０が、ニーパネル１６に組み付けられてエアバッグ組付体ＳＡ（図１０・１１参照）を形成し、各部材を組み付けて一体化したエアバッグ組付体ＳＡを車両に取り付けて、エアバッグ装置Ｓを車両に搭載している。
【００２３】
ニーパネル１６は、板金製として、図２〜６に示すように、平板状の本体部１７と、折り畳んだエアバッグ４６とインフレーター４１とを収納する収納部２３と、を備えて構成されている。
【００２４】
収納部２３は、車両後方側の斜め下向きに開口２３ａを設けた有底の箱形状としている。実施形態の場合、収納部２３は、略長方形形状の底壁部２６と略四角筒形状の周壁部２４とを備えた略直方体の箱形状として、開口２３ａを囲む周壁部２４には、車両の左右方向で対向する壁部２４ａ・２４ｂに、それぞれ、インフレーター４１を取り付けるための大小の円形に開口した取付孔２７・２８を配設させて構成されている。取付孔２７は、インフレーター４１の後述する円柱状の本体部４１ａを嵌挿させて、内周面で、本体部４１ａの外周面を支持可能に形成され、取付孔２８は、インフレーター４１の本体部４１ａを挿通不能として、インフレーター４１の後述する雄ねじ部４１ｃを突出可能な内径寸法としている。収納部２３へのインフレーター４１の取り付けは、収納部２３の外方から取付孔２７に、インフレーター４１の雄ねじ部４１ｃ側を挿入させて、雄ねじ部４１ｃを取付孔２８から突出させ、雄ねじ部４１ｃにナット４２を螺合させることにより、行っている。
【００２５】
そして、周壁部２４の外周面には、先端側の係止鉤部２５ａを開口２３ａから離れるように底壁部２６側に反転させた複数の断面略Ｊ字形状のフック２５が固着されている。フック２５は、エアバッグカバー３０における後述するヒンジ部３７側となる部位（収納部周壁部２４の下面側の部位）に４個配設され、エアバッグカバー３０の後述する扉部３９の先端３９ａ側の部位（収納部周壁部２４の上面側の部位）に３個配設され、車両の左右方向両側の部位に、それぞれ、１個ずつ配設されている。
【００２６】
本体部１７は、収納部２３の開口２３ａの周縁から延びて、着座した運転者ＭＤの左右両膝Ｋ（ＫＬ・ＫＲ）の前方側を広く覆えるように、略長方形形状に形成されて、周縁の四隅に、それぞれ、車両のボディ１側に連結させるための取付片部２１を配設させている。なお、本体部１７における開口２３ａの上縁側付近は、コラムカバー１０の下面１０ａ側を車両後方側に突出させるための凹部１７ａを備えて、さらに、その下面１０ａの湾曲状態に対応させて、車両後方側に突出するように湾曲している。そして、開口２３ａの周縁から本体部１７の外周縁までの間には、本体部１７の剛性を高めるためのリブ１８ａが形成され、これらリブ１８ａは、その車両後方側の面で、エアバッグカバー３０の後述する一般部３１の支持できるように、支持部１８を構成している。
【００２７】
そして、本体部１７の収納部開口２３ａの周縁には、表裏を貫通するように、略長方形形状に開口する複数の貫通孔１９が形成されている。これらの貫通孔１９は、エアバッグカバー３０における各フック２５に係止させる取付片３３を挿通可能に、各フック係止鉤部２５ａの周壁部２４に沿った延長線上に、それぞれ配置されている。
【００２８】
また、本体部１７における収納部２３から離れた左右両側には、表裏を貫通するように、複数の取付孔２０が形成されている。これらの取付孔２０は、熱カシメを利用してエアバッグカバー３０をニーパネル１６に取り付ける部位となる。すなわち、エアバッグカバー３０は、エアバッグカバー３０の後述する取付脚部３２を各取付孔２０に挿通させて、各取付脚部３２の先端３２ａを溶融させつつ拡径させ、固化させた先端３２ａを取付孔２０から抜けないようにして、フック２５と併用して、ニーパネル１６に取り付けられることとなる。
【００２９】
さらに、ニーパネル１６の各連結片部２１には、ボディ１側にボルト２９（図４参照）止めするための連結孔２１ａが形成され、各連結片部２１を取り付けるボディ１側には、ブラケット３・４が配設されている。これらのブラケット３・４は、衝撃エネルギー吸収体を構成するものであり、ニーパネル１６に前方側への衝撃力が作用した際、塑性変形して前方側への衝撃力のエネルギーを吸収することとなる。ブラケット３・３は、ボディ１側のインパネリインフォースメント２に連結されており、ブラケット４・４は、ボディ１側の図示しないセンターブレースやフロントボディピラー等に連結されている。
【００３０】
なお、実施形態では、本体部１７と収納部２３と備えたニーパネル１６を、プレス加工して、一体的に形成した場合を示したが、適宜、板金を溶接して、ニーパネル１６を形成してもよい。
【００３１】
エアバッグカバー３０は、ポリオレフィン系等の熱可塑性エラストマーから形成されて、図２〜６に示すように、ニーパネル１６の外形形状より大きな外形形状として、ニーパネル１６の車両後方側を覆えるように、構成されている。
【００３２】
なお、エアバッグカバー３０は、アッパパネル１２ａとロアパネル１２ｂとからなるインパネ１２におけるコラムカバー１０の周縁のロアパネル１２ｂ側に配置されて、インパネ１２から突出するコラムカバー１０の下側周縁を覆うこととなる。そのため、エアバッグカバー３０は、車両後方側から見て、中央付近に、コラムカバー１０を後方へ突出させるように、下方へ凹む凹部３０ｄを備えて、凹部３０ｄの下方に、上縁側を、コラムカバー下面１０ａ側の曲面に対応させて車両後方側へ湾曲させた隆起部３０ｃを配設させ、隆起部３０ｃの左右両側に、ニーパネル本体部１７の左右両側を覆うように延びる平板状部３０ａ・３０ｂを、配設させて構成されている。
【００３３】
そして、エアバッグカバー３０は、ニーパネル収納部２３の開口２３ａを覆う扉部３９と、ニーパネル本体部１７の車両後方側を覆う一般部３１と、を備えて構成されている。
【００３４】
扉部３９は、隆起部３０ｃの下方側に配置されて、開口２３ａより僅かに大きく覆う略長方形の板状に形成され、その外周縁の逆Ｕ字形状の部位には、扉部３９が下開きで開くように、一般部３１と連結された薄肉の破断予定部３５が、形成されている。破断予定部３５は、扉部３９が膨張するエアバッグ４６に押された際に容易に破断するように、車両前方側の面に連続的若しくは断続的な凹溝を設けて、形成されている。
【００３５】
また、扉部３９の下縁側には、破断予定部３５が破断して扉部３９が開く際、扉部３９の回転中心となるヒンジ部３７が、形成されている。このヒンジ部３７は、インテグラルヒンジとしており、破断しない範囲内の肉厚で、一般部３１や扉部３９より薄肉に形成されている。
【００３６】
そして、一般部３１における収納部開口２３ａの周縁全周の近傍には、ニーパネル１６の本体部１７における各貫通孔１９を貫通する複数の取付片３３が、車両前方側に突設されている。各取付片３３は、略長方形形状の板状としている。各取付片３３には、周縁をフック２５の係止鉤部２５ａに係止させるための長方形形状に開口する係止孔３３ａが、形成されている。
【００３７】
また、一般部３１の所定位置には、ニーパネル１６の本体部１７における各取付孔２０の周縁に、熱カシメして係止させる複数の取付脚部３２が形成されている。各取付脚部３２は、図６・１０に示すように、熱カシメ前の状態では取付孔２０を貫通可能な丸棒状として、図３・１１に示すように、熱カシメ後には押し潰される頭部３２ａを、先端に備えるとともに、元部側に、頭部３２ａの熱カシメ固定時に取付孔２０の周縁のニーパネル本体部１７に当接する円柱状や十字断面形状等の基部３２ｂを、備えて構成されている。
【００３８】
インフレーター４１は、図１〜３に示すように、電気信号を入力させて膨張用ガスＧを吐出可能に構成されたシリンダタイプとして構成され、ガス吐出口４１ｂを備えた円柱状の本体部４１ａを備え、本体部４１ａの一端から雄ねじ部４１ｃを突出させて構成されている。このインフレーター４１は、既述したように、取付孔２７からニーパネル収納部２３内に挿入されて、取付孔２８から突出した雄ねじ部４１ｃにナット４２を螺合させることにより、本体部４１ａにおける雄ねじ部４１ｃ側の端面が収納部２３の取付孔２８周縁側に圧接され、本体部４１ａにおける雄ねじ部４１ｃから離れた外周面が、取付孔２７の内周面に支持されて、ニーパネル１６の収納部２３内に収納されて保持されている。なお、収納部２３内への収納時には、インフレーター４１は、エアバッグ４６の後述する取付孔４７ａ・４７ｂを貫通することとなる。
【００３９】
また、このインフレーター４１は、ステアリングホイール６に搭載された図示しないエアバッグ装置を作動させる制御装置からの電気信号を、ステアリングホイール用エアバッグ装置と同時に入力させて、作動されることとなる。本体部４１ａの収納部２３から突出している側の端面には、エアバッグ作動回路に接続されるリード線４４を接続させたコネクタ４３が、配設されている。
【００４０】
エアバッグ４６は、可撓性を有したポリエステルやポリアミド等の織布から形成されて、図４・７・８に示すように、展開膨張完了時の形状を略長方形板状として、構成されている。実施形態の場合、エアバッグ４６は、それぞれ略長方形形状のコラムカバー１０側の壁部４７と運転者ＭＤ側の壁部４８との二枚の織布から構成されて、壁部４７・４８の周縁相互を縫合して形成されている。
【００４１】
コラムカバー側壁部４７の下部側には、二つの取付孔４７ａ・４７ｂが形成されている。取付孔４７ａは、インフレーター４１の本体部４１ａを挿通可能に、本体部４１ａの外径寸法と略等しい内径寸法として構成され、取付孔４７ｂは、本体部４１ａの外径寸法より内径寸法を小さくして、雄ねじ部４１ｃを挿通可能に構成されている。そして、エアバッグ４６は、取付孔４７ａにインフレーター本体部４１ａが挿入され、取付孔４７ｂに雄ねじ部４１ｃが挿入されて、取付孔４７ａ・４７ｂの内周面をインフレーター４１の本体部４１ａや雄ねじ部４１ｃに支持させて、収納部２３に収納されたインフレーター４１を利用して、ニーパネル１６に取り付けられている。
【００４２】
また、運転者側壁部４８は、インフレーター４１の配置位置における車両後方側の位置に一致する下部中央部位４８ｂを含んで、エアバッグ４６の左右方向の中央付近における中央部位４８ａと、平らに展開した状態のエアバッグ４６における左右の両縁４６ａ・４６ｂより中央側で、かつ、中央部位４８ａに連なる中央部位４８ａ近傍の左右の連接部位４８ｃ・４８ｃと、を具備して構成されている。
【００４３】
そして、実施形態のエアバッグ４６では、後述するテザー５３の配置位置で上下に分割されるように、インフレーター４１を収納した側の下膨張部５０と、下膨張部５０の上方側に延びた上膨張部５１と、を備えて構成されている。下膨張部５０は、膨張用ガスＧの上流側の部位として、ニーパネル収納部２３の開口２３ａから車両後方側へ突出して、開口２３ａ周縁のエアバッグカバー３０における一般部３１の車両後方側の面で、かつ、運転者ＭＤの膝Ｋ（ＫＬ・ＫＲ）の前方側を覆い可能としている。また、上膨張部５１は、膨張用ガスＧの下流側の部位として、下膨張部５０に連通するとともに、下膨張部５０から、コラムカバー１０の下面１０ａに沿うように、上方へ突出し、開口２３ａの周縁のエアバッグカバー３０における一般部３１の車両後方側の面から、少なくともコラムカバー下面１０ａ側の上端１０ｂ付近までを、覆い可能としている。なお、実施形態の場合、展開膨張時の下膨張部５０は、余裕を持って運転者ＭＤの両膝ＫＬ・ＫＲを保護できるように、開口２３ａより左右方向の幅寸法が大きくなるように、設定されている。
【００４４】
また、エアバッグ４６内には、図７・８に示すように、コラムカバー側・運転者側壁部４７・４８相互を連結して、展開膨張時における下膨張部５０と上膨張部５１との厚さ寸法を一定として、運転者ＭＤの膝Ｋとコラムカバー下面１０ａとの間にエアバッグ４６を円滑に侵入させるための厚さ規制手段としてのテザー５２・５３が、配設されている。テザー５２・５３は、エアバッグ４６の壁部４７・４８と同様に、可撓性を有した布材から形成されて、壁部４７・４８に縫着されており、実施形態の場合、インフレーター４１の配置部位における上方側において、車両左右方向と略平行に並設されており、それぞれの左右の両端を、エアバッグ４６の左右の両端４６ａ・４６ｂから離して、配設されている。また、テザー５３は、厚さ規制手段として配置されると同時に、インフレーター４１から吐出された膨張用ガスＧを、エアバッグ４６における左右両縁４６ａ・４６ｂ側に向かわせつつ、膨張用ガスＧを上膨張部５１へ案内するガス流れ案内材としての役割も果たしている。
【００４５】
即ち、車両左右方向に配設されるテザー５３が、インフレーター４１の上方側を塞いで、テザー５３の左端５３ａとエアバッグ左縁４６ａとの間と、テザー５３の右端５３ｂとエアバッグ右縁４６ｂとの間と、にガス流通孔５４・５４を設けて、下流側部位としてのエアバッグ上膨張部５１に膨張用ガスＧが流される際に、上流側部位としてのエアバッグ下膨張部５０内で、インフレーター４１から吐出される膨張用ガスＧを左右方向に向かいつつ上方へ流れるように、配設されている。
【００４６】
さらに、実施形態のエアバッグ４６では、展開膨張の初期段階で、上膨張部５１が展開膨張を完了させる前に、下膨張部５０が、扉部３９の開いた際の開口４０におけるエアバッグカバー３０の左右の周縁を広く覆えるように、折り畳まれている。実施形態の場合、次のような縦折り工程と横折り工程とを経て、エアバッグ４６を折り畳んでいる。
【００４７】
縦折り工程は、図９Ａ〜図９Ｄに示すように、運転者側壁部４８をコラムカバー側壁部４７に当てて平らに展開した状態で、左右両縁４６ａ・４６ｂを中央部位４８ａ側に接近させるように縦折りして、収納部２３内に収納可能な左右方向の幅寸法Ｂ１に折り畳む工程であって、特に、エアバッグ４６の左右両縁側の折り畳み部位５７・５７を、運転者側壁部４８の左右の連接部位４８ｃ・４８ｃにおけるコラムカバー側壁部４７側に、それぞれ、配置させるように、エアバッグ４６を縦折りすることに特徴がある。縦折り工程におけるエアバッグ４６の左右両縁側の折り畳み部位５７・５７は、蛇腹折りや、左右両縁４６ａ・４６ｂをコラムカバー側壁部４７側に巻くロール折り等により、折り畳むことが例示できる。
【００４８】
また、横折り工程は、縦折り工程を経た後に行う工程であって、図９Ｄ・図９Ｅに示すように、縦折り工程終了後のエアバッグ上縁４６ｃをインフレーター４１の配置位置側に接近させるように横折りして折り畳み部位５８を形成し、収納部２３内に収納可能な上下方向の厚さ寸法に折り畳む工程である。
【００４９】
次に、エアバッグ装置Ｓの車両への搭載について説明すると、まず、エアバッグ４６を折り畳む。エアバッグ４６の折り畳みは、実施形態の場合、既述した図９Ａ〜９Ｅに示すように、縦折り工程と横折り工程との二工程で行う。
【００５０】
そして、縦折り工程では、図９Ａに示すように、運転者側壁部４８をコラムカバー側壁部４７に当てて平らに展開した状態から、図９Ｂに示すように、エアバッグ４６の左右両縁４６ａ・４６ｂを運転者側壁部４８の中央部位４８ａに接近させるように、左右両縁４６ａ・４６ｂを、それぞれ、コラムカバー側壁部４７側に向かって折り畳む。さらに、図９Ｃに示すように、エアバッグ４６における折り畳んだ後の左右両縁５５・５６を運転者側壁部４８の中央部位４８ａに接近させるように、両縁５５・５６を、それぞれ、コラムカバー側壁部４７側に向かって折り畳んで、折り畳み部位５７・５７を形成する。次いで、図９Ｄに示すように、収納部２３の左右方向の収納幅寸法に対応させるために、折り畳み部位５７・５７を、運転者側壁部４８の左右の連接部位４８ｃ・４８cにおけるコラムカバー側壁部４７側にそれぞれ配置された状態で、運転者側壁部４８の中央部位４８ａにおける外表面上（車両後方側上・運転者側上）に載せるように折り畳んで、縦折り工程を完了する。
【００５１】
縦折り工程後の横折り工程では、図９Ｄ・図９Ｅに示すように、縦折り後のエアバッグ４６を、上縁４６ｃからコラムカバー側壁部４７側に向かってロール巻するように折り畳んで、折り畳み部位５８を形成し、収納部２３の上下方向の収納厚さ寸法に対応させて、横折り工程を完了し、エアバッグ４６の折り畳み作業を完了させる。
【００５２】
そして、エアバッグ４６の折り畳み後、折り崩れ防止用の破断可能な図示しないラッピングフィルムにより、エアバッグ４６をくるんで、取付孔２７・４７ａ相互と取付孔２８・４７ｂ相互とをそれぞれ一致させるように、エアバッグ４６を収納部２３内に収納させる。なお、取付孔４７ａ・４７ｂの部位のラッピングフィルムは、破断させておく。
【００５３】
その後、雄ねじ部４１ｃを、取付孔２７・４７ａ側から、収納部２３内に収納させたエアバッグ４６内に挿入させ、さらに、取付孔４７ｂ・２８から突出させて、突出した雄ねじ部４１ｃにナット４２を締め付け、本体部４１ａにおける雄ねじ部４１ｃ側の端面を、エアバッグ４６の取付孔４７ａ周縁を介在させて、収納部２３の内周面に圧接させれば、インフレーター４１とエアバッグ４６とを収納部２３に取り付けることができる。
【００５４】
そして、ニーパネル１６にエアバッグカバー３０を取り付ける。この取り付けは、図１０・１１に示すように、まず、ニーパネル１６の車両後方側から、各貫通孔１９に対して、対応する取付片３３を挿入させるとともに、各取付孔２０に対して、対応する取付脚部３２の丸棒状の頭部３２ａを挿入させる。
【００５５】
この時、各取付片３３は、図１０・１１の二点鎖線に示すように、フック２５の係止鉤部２５ａにおける車両後方側の湾曲したガイド面２５ｂに干渉して、収納部２３から離れるように弾性変形し、係止孔３３ａが係止鉤部２５ａの位置に配置されたならば、復元して、係止孔３３内に係止鉤部２５ａが挿入される。すなわち、各取付片３３は、単に、貫通孔１９に貫通させるだけで、自動的に、係止孔３３の周縁が係止鉤部２５ａに係止されることとなる。
【００５６】
また、各取付孔２０から突出した取付脚部３２の頭部３２ａは、係止脚部３２の基部３２ｂを各取付孔２０の周縁に当設させた状態で、加熱して拡径させる熱カシメにより、ニーパネル本体部１７の車両前方側の面における取付孔２０の周縁に係止させる。その結果、エアバッグカバー３０をニーパネル１６に取り付けることができて、エアバッグ組付体ＳＡを形成することができる。
【００５７】
このようなエアバッグ組付体ＳＡは、ニーパネル本体部１７の各連結片部２１を、ボディ１側のブラケット３・４にボルト２９止めして連結させれば、車両に膝保護用エアバッグ装置Ｓを搭載することができる。
【００５８】
なお、エアバッグ装置Ｓの車両搭載後には、リード線４４をエアバッグ作動回路に結線するとともに、インパネ１２のアッパパネル１２ａやロアパネル１２ｂ、さらには、アンダーカバー１４（図１・２参照）を車両に搭載することとなる。
【００５９】
車両へのエアバッグ装置Ｓの搭載後、インフレーター４１に所定の電気信号が入力されれば、ガス吐出口４１ｂから膨張用ガスＧが吐出されて、エアバッグ４６は、膨張して、図示しないラッピングフィルムを破断するとともにエアバッグカバー３０の扉部３９を押し、破断予定部３５を破断させて、ヒンジ部３７を回転中心として扉部３９を下開きで開かせ、その結果、収納部２３の開口２３ａから、扉部３９が開いて形成されたエアバッグカバー３０の開口４０を経て、車両後方側へ突出し、さらに、横折りと縦折りとを解消しつつ、コラムカバー下面１０ａに沿うように、上方に向かって大きく展開膨張することとなる（図１２のＡ・Ｂ・図１３参照）。
【００６０】
このエアバッグ４６の展開膨張時、エアバッグカバー３０は、一般部３１における収納部開口２３ａの周縁近傍の複数箇所に配設させた取付片３３を、ニーパネル１６の貫通孔１９を貫通させて収納部２３に取り付けているため、収納部開口２３ａの周縁近傍における一般部３１の破断予定部３５やヒンジ部３７の部位が、収納部２３に対して移動し難く、エアバッグ４６の押圧力が的確に破断予定部３５に作用して、破断予定部３５が円滑に破断する。また、開き時の回転中心となるヒンジ部３７も、収納部２３に対して移動し難く、扉部３９の開き動作を安定させることができる。その結果、エアバッグカバー３０を熱可塑性エラストマー等の合成樹脂から形成しても、エアバッグ４６に押された扉部３９は、円滑に、開くこととなる。
【００６１】
したがって、実施形態の膝保護用エアバッグ装置Ｓでは、一体化させた扉部３９を有するエアバッグカバー３０を、着座した乗員ＭＤの膝Ｋの前方側における広い面積に配置されるニーパネル１６に対して、取り付けても、エアバッグ４６に押された扉部３９を、円滑に開かせることができる。
【００６２】
なお、破断予定部３５の円滑な破断と扉部３９の円滑な開き動作とを確保するためには、開口２３ａの周縁において、少なくとも、開く扉部３９のヒンジ部３７から離れた先端３９ａ側の破断予定部３５の近傍と、ヒンジ部３７の近傍とに、ニーパネル本体部１７を貫通して収納部２３に取り付けられる取付片３３を配設させればよい。
【００６３】
但し、実施形態のように、収納部２３における略長方形状の開口２３ａの周縁全周に、取付部３３を配設させれば、一層、円滑な破断予定部３５の破断と安定した扉部３９の開き動作とを確保することができる。
【００６４】
また、実施形態の場合には、一枚扉の扉部３９を開かせて、その開口４０からエアバッグ４６を突出させる場合を示したが、観音扉のような両開きタイプの二枚の扉部により、収納部２３の開口２３ａを覆うように構成してもよい。この場合、破断予定部は、車両後方側から見て、「Ｈ」字形状若しくは「エ」字形状に配設させることとなる。これらの場合には、ヒンジ部は、破断予定部が「Ｈ」字形状に形成されれば、「Ｈ」字の左右両側の縦棒部位の端末相互を結ぶように、配設させ、破断予定部が「エ」字状に形成されれば、「エ」字の上下両側の横棒部位の端末相互を結ぶように、配設させて、構成することとなる。そして、これらの場合では、少なくともヒンジ部の近傍となる収納部の開口周縁に、取付片を配設することが望ましい。
【００６５】
さらに、略長方形形状に開口した開口２３ａの周縁に配置させる取付片３３は、開口２３ａの開口形状の一辺に配設させる場合、取付強度を確保できれば、適宜、形状等を大きくして、一つ（壁部２４ａ・２４ｂ側参照）としたり、あるいは、複数（開口２３ａ周縁の上縁側や下縁側参照）としてもよい。
【００６６】
そしてまた、実施形態のエアバッグカバー３０の各取付片３３は、ニーパネル１６における収納部開口２３ａの周縁の貫通孔１９に貫通させるだけであって、ニーパネル１６の本体部１７は、外形形状が小さくならないことから、エアバッグ４６の非膨張状態で、乗員ＭＤの両膝Ｋ（ＫＬ・ＫＲ）が干渉してきても、広い面積で、左右両膝ＫＬ・ＫＲを受けることが可能となり、円滑に、衝撃エネルギー吸収体としてのブラケット３・４を変形させることができる。勿論、この態様は、ニーパネル１６の本体部１７が、エアバッグカバー３０の一般部３１を介在させて、膨張を完了させたエアバッグ４６の車両前方側を支持できることにもなり、展開膨張を完了させたエアバッグ４６は、ニーパネル本体部１７によって、安定して支持されることとなる。
【００６７】
さらに、実施形態の膝保護用エアバッグ装置Ｓでは、エアバッグ４６、インフレーター４１、エアバッグカバー３０、及び、ニーパネル１６、を予め一体化してエアバッグ組付体ＳＡをすることができる。そのため、エアバッグ組付体ＳＡを予め形成させておけば、アセンブリー化した状態で、エアバッグ４６等を運搬・保管等することができ、車両に取り付けるまでの各部材の取扱性が容易となる。
【００６８】
さらにまた、実施形態では、収納部２３の各フック２５を、エアバッグカバーの各取付片３３の係止孔３３ａに、挿入させ、各フック２５の係止鉤部２５ａで取付片３３を係止すれば、取付片３３の収納部２３への取付を完了させることができるため、エアバッグカバー３０のニーパネル１６への取付工数・コストを低減させることができる。特に、実施形態では、各取付片３３を、単に、貫通孔１９に貫通させるだけで、自動的に各取付片３３が撓んで、係止孔３３の周縁が係止鉤部２５ａに係止されることから、一層、取付工数を低減することができる。ちなみに、この点を考慮しなければ、フック２５を設けることなく、ボルト・ナットやリベット等を利用して、各取付片３３を収納部２３に取り付けてもよい。
【００６９】
なお、実施形態では、展開膨張するエアバッグ４６の初期段階では、テザー５３による左右方向の膨張用ガスＧの流れや折り畳み工程によって、まず、図１２のＡに示すように、エアバッグ４６の下膨張部５０が左右方向に広がった状態で展開膨張し、その状態で、図１２のＢに示すように、上膨張部５１が上方側に展開膨張する。すなわち、エアバッグ４６は、展開膨張する初期段階で、運転者ＭＤ側に突出することを極力抑えて、運転者ＭＤの両膝ＫＬ・ＫＲの前方側を左右方向の広い範囲で覆うことができ、両膝Ｋ（ＫＬ・ＫＲ）の前方移動が素早くとも、迅速に保護することが可能となる。
【００７０】
また、実施形態では、運転者ＭＤの膝Ｋを保護するために、運転者ＭＤの車両前方側に配置されるエアバッグ装置Ｓを例に採り説明したが、図１４に示すように、助手席に着座した助手席搭乗者ＭＰの両膝Ｋ（ＫＬ・ＫＲ）を保護するように、助手席に着座した乗員ＭＰの車両前方側となる位置に、エアバッグ装置Ｓを配置させてもよい。
【図面の簡単な説明】
【図１】本発明の一実施形態である膝保護用エアバッグ装置の使用状態を示す車両前後方向の概略縦断面図である。
【図２】本発明の一実施形態である膝保護用エアバッグ装置の車両前後方向の概略拡大縦断面図である。
【図３】図２のIII−III部位の断面図である。
【図４】同実施形態の膝保護用エアバッグ装置の使用状態を示す車両後方側から見た概略正面図である。
【図５】同実施形態で使用する板状部材としてのニーパネルとエアバッグカバーとの分解正面側斜視図である。
【図６】同実施形態で使用する板状部材としてのニーパネルとエアバッグカバーとの分解背面側斜視図である。
【図７】同実施形態で使用するエアバッグの正面図である。
【図８】図７のVIII−VIII部位の概略断面図である。
【図９】同実施形態のエアバッグの折り畳みを示す概略図である。
【図１０】同実施形態のエアバッグカバーを、板状部材としてのニーパネルに取り付ける状態を示す図である。
【図１１】同実施形態のエアバッグカバーを、板状部材としてのニーパネルに取り付ける状態を示す図であり、図１０の後の状態を示す。
【図１２】同実施形態のエアバッグの展開膨張を説明する車両後方側から見た概略正面図である。
【図１３】同実施形態のエアバッグが展開膨張完了した状態を示す車両前後方向に沿った状態の概略縦断面図である。
【図１４】本発明の一実施形態である膝保護用エアバッグ装置を助手席の車両前方側に配置させた状態を示す車両後方側から見た概略正面図である。
【符号の説明】
１６…（板状部材）ニーパネル、
２３…収納部、
２３ａ…開口、
２５…フック、
３０…エアバッグカバー、
３５…破断予定部、
３７…ヒンジ部、
３９…扉部、
４１…インフレーター、
４６…エアバッグ、
Ｍ…（ＭＤ…運転者、ＭＰ…助手席搭乗者）乗員、
Ｓ…膝保護用エアバッグ装置。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a knee protection airbag device capable of protecting the knees of a seated occupant by an airbag that is inflated by inflating gas.
[0002]
[Prior art and its problems]
2. Description of the Related Art Conventionally, as a knee protection airbag device for protecting a passenger's knee including a driver or the like, as disclosed in JP-A-9-123862, a lower position of a steering column is used to protect the passenger's knee. An airbag that is deployed and inflated toward the lower surface of the upper column cover when activated, an inflator that supplies inflation gas to the airbag, a case that houses the airbag and the inflator, and a stored air There has been an air bag cover that covers the bag in a projectable manner.
[0003]
In the airbag apparatus having such a configuration, it is conceivable that a case or the like is disposed on a plate-like member disposed on the front side of a seated passenger, for example, a knee panel (also referred to as a knee bolster).
[0004]
The knee panel is connected to an impact energy absorber disposed on the vehicle front side of the knee panel so as to widely cover the front side of the seated occupant. The knee panel receives the knee of the occupant moving forward during a frontal collision of the vehicle, moves to the front side of the vehicle together with the knee, and deforms the impact energy absorber disposed on the front side of the vehicle, thereby It acts to reduce the impact of the moving knee.
[0005]
And when storing an airbag and an inflator in such plate-shaped members, such as a knee panel, the airbag cover which covers the folded airbag needs to be attached to the plate-shaped member.
[0006]
This airbag cover covers the folded rear airbag and covers the folded airbag so as to prevent the appearance design from deteriorating, and is opened by being pushed by the airbag when inflated. It is desirable to form the part integrally rather than disposing it separately. In such a configuration, the part to be broken is provided around the door, and the door part is formed integrally with the airbag cover itself. It will be.
[0007]
However, when an airbag cover having an integrated door portion is attached to the plate member, there is a problem in smoothly opening the door portion by breaking the portion to be broken.
[0008]
In view of the above problems, the present invention pushes an airbag cover having an integrated door portion against the airbag even if it is attached to a plate-like member disposed on the front side of a seated passenger's knee. It is an object of the present invention to provide a knee protection airbag device that can smoothly open the door portion.
[0009]
[Means for Solving the Problems]
  A knee protection airbag device according to the present invention includes a folded knee protection airbag on a plate-like member disposed on the front side of a seated occupant's knee, and an inflator that supplies inflation gas to the airbag. Is an airbag device for knee protection that is configured by attaching an airbag cover that covers the stored airbag in a projectable manner,
  The plate-like memberBut,
  A box-shaped storage portion with a bottom that opens the vehicle rear side and stores the airbag and the inflatorWhen,
  A plate-like body formed so as to extend from the periphery of the opening of the storage portion, and is attached to the vehicle body side, and a main body portion capable of supporting the vehicle front side of the airbag when the inflation is completed;
  Composed of
  The airbag cover is made of synthetic resin,
  A door portion that covers the opening of the storage portion and is pushed by the airbag at the time of inflation to open a thin rupture portion that is thin at the periphery, and
  A hinge part disposed around the door part and serving as a center of rotation of the door part at the time of opening;
  A general portion that is disposed around the door portion with the planned break portion and the hinge portion interposed therebetween, and covers the vehicle rear side of the periphery of the storage portion in the plate member;
  And configured with
  In a plurality of locations in the vicinity of the opening periphery of the storage section in the general section, mounting pieces that are attached to the storage section are arranged, and configured.
  The plate-like memberIn the body partThe periphery of the opening of the storage part inThe part to becomeFurther, a plurality of through holes into which the mounting pieces can be inserted are formed.
[0010]
  Each of the mounting pieces of the airbag cover includes a locking hole, and the storage portion includes a plurality of hooks that can be inserted into the locking hole and lock the mounting pieces. It is desirable to provide and configure.
  In addition, the hook is disposed so as to be reversed to the side away from the opening of the storage portion, and the locking collar portion inserted into the locking hole and the attachment piece are separated from the storage portion. And a guide surface that guides elastically deformable,
  When the mounting piece is inserted into the through-hole, the mounting piece interferes with the guide surface and elastically deforms away from the storage portion, and the locking hole is disposed at the position of the locking hook portion. At this time, it is desirable to restore and insert the locking collar into the locking hole.
  Furthermore, the plate-like member is preferably made of sheet metal.
  Furthermore, the plate-like member is configured to include a flat plate-like main body formed so as to extend from the periphery of the opening of the storage portion.
  It is desirable that an attachment piece for attaching the plate-like member to the body side of the vehicle is disposed on the periphery of the main body.
  Furthermore, it is desirable that the main body portion includes a support portion that can support a general portion of the airbag cover.
[0011]
【The invention's effect】
In the knee protection airbag device according to the present invention, when the inflator is activated and the inflation gas is discharged from the inflator, the airbag is inflated by the inflation gas. Then, the airbag pushes the door portion of the airbag cover, breaks the planned breakage portion, opens the door portion with the hinge portion as the rotation center, and as a result, protrudes toward the vehicle rear side from the opening of the storage portion, Thus, the knee is greatly expanded and inflated to protect the knee.
[0012]
When the airbag is deployed and inflated, the airbag cover is attached to the storage portion through the plate-like member, with attachment pieces disposed at a plurality of locations near the periphery of the storage portion opening in the general portion. The planned breakage part of the general part and the hinge part in the vicinity of the opening periphery of the part are difficult to move relative to the storage part, and the pressing force of the airbag accurately acts on the planned breakage part so that the planned breakage part is smooth Break. In addition, the hinge portion serving as the rotation center at the time of opening is also difficult to move with respect to the storage portion, and the opening operation of the door portion can be stabilized. As a result, even if the airbag cover is formed from a synthetic resin such as a thermoplastic elastomer, the door portion pushed by the airbag is smoothly opened.
[0013]
Therefore, in the airbag device for knee protection according to the present invention, even if the airbag cover having the integrated door portion is attached to the plate-like member disposed on the front side of the seated occupant's knee, The door part pushed by the airbag can be opened smoothly.
[0014]
In addition, each attachment piece of the air bag cover is only penetrated to the opening peripheral edge of the storage portion in the plate-like member, and the outer shape of the plate-like member does not become small. Even if the knees interfere with each other, it is possible to receive the knees over a wide area. Of course, this mode can also support the vehicle front side of the airbag in which the plate-like member has been inflated, and the airbag that has been deployed and inflated is stably supported by the plate-like member. It becomes.
[0015]
Further, in the airbag device for knee protection according to the present invention, the airbag and the inflator are stored in a storage portion provided on a plate-like member, and further, a door portion that covers the folded airbag is provided, and the plate It is the structure which attaches the airbag cover which has the general part which covers the vehicle back side in the periphery of the accommodating part opening of a shaped member to a plate-shaped member. That is, the airbag, the inflator, the airbag cover, and the plate member can be integrated in advance. Therefore, if the airbag, inflator, airbag cover, and plate member are integrated in advance, the airbag can be transported and stored in an assembled state until it is attached to the vehicle. The handleability of each member becomes easy.
[0016]
And when comprised as described in Claim 2, each hook of a storage part is inserted in the locking hole of each attachment piece of an airbag cover, and an attachment piece is latched by each hook. In this case, since the attachment of the attachment piece to the storage portion can be completed, it is possible to reduce the man-hour and cost for attaching the airbag cover to the plate-like member.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0018]
As shown in FIGS. 1 to 4, the knee protection airbag apparatus S of the embodiment is provided with a steering column 7 on the front side of the vehicle of the driver MD so that the knee K of the driver MD as the occupant M can be protected. It is arranged below.
[0019]
In addition, the upper and lower sides, the left and right, and the front and rear in this specification correspond to the upper and lower, left and right, and front and rear of the vehicle when the knee protection airbag device S is mounted on the vehicle.
[0020]
As shown in FIG. 1, the steering column 7 includes a main shaft 8 connected to the steering wheel 6 and a column tube 9 that covers the periphery of the main shaft 8, and the main shaft 8, the column tube 9, A tilt mechanism (not shown) that can adjust the angle of the ring surface of the steering wheel 6, a telescopic mechanism (not shown) that can be stopped by moving the steering wheel 6 in the axial direction of the shaft, and the like are disposed between the two. .
[0021]
The column cover 10 is made of a synthetic resin having a substantially rectangular tube shape or the like, and is disposed along the axial direction of the steering column 7 so as to cover the steering column 7 below the steering wheel 6. That is, the column cover 10 is disposed so as to incline rearward so that the front side of the vehicle is disposed downward and the rear side of the vehicle is disposed upward. And the lower surface 10a of the site | part which protrudes from the instrument panel (henceforth an instrument panel) 12 in the column cover 10 is made into the substantially rectangular shape, and is formed in the vehicle back-and-forth direction curved surface shape.
[0022]
The knee protection airbag device S includes a folded airbag 46, an inflator 41 that supplies inflation gas to the airbag 46, an airbag cover 30 that covers the folded airbag 46, and a knee panel as a plate member. 16. In the airbag device S of the embodiment, the airbag 46, the inflator 41, and the airbag cover 30 are assembled to the knee panel 16 to form an airbag assembly SA (see FIGS. 10 and 11). The airbag assembly SA, which is an integrated assembly of members, is attached to the vehicle, and the airbag device S is mounted on the vehicle.
[0023]
As shown in FIGS. 2 to 6, the knee panel 16 is made of a sheet metal and includes a flat plate-like main body portion 17 and a storage portion 23 that stores the folded airbag 46 and the inflator 41.
[0024]
The storage unit 23 has a bottomed box shape with an opening 23a obliquely downward on the vehicle rear side. In the case of the embodiment, the storage portion 23 has a substantially rectangular parallelepiped box shape including a substantially rectangular bottom wall portion 26 and a substantially square cylindrical peripheral wall portion 24, and the peripheral wall portion 24 surrounding the opening 23 a The wall portions 24a and 24b facing each other in the left-right direction are configured by arranging mounting holes 27 and 28 that are open in large and small circles for mounting the inflator 41, respectively. The mounting hole 27 is formed so that a cylindrical main body portion 41a, which will be described later, of the inflator 41 is fitted and supported on the inner peripheral surface so that the outer peripheral surface of the main body portion 41a can be supported. The mounting hole 28 is a main body portion of the inflator 41. 41a is made incapable of being inserted, and a male thread portion 41c, which will be described later, of the inflator 41 has an inner diameter that can be projected. The inflator 41 is attached to the storage portion 23 by inserting the male screw portion 41c side of the inflator 41 into the attachment hole 27 from the outside of the storage portion 23, and projecting the male screw portion 41c from the attachment hole 28 to the male screw portion 41c. This is done by screwing the nut 42 together.
[0025]
A plurality of hooks 25 having a substantially J-shaped cross section are fixed to the outer peripheral surface of the peripheral wall portion 24 by reversing the locking collar portion 25a on the front end side toward the bottom wall portion 26 so as to be away from the opening 23a. . Four hooks 25 are disposed in a portion of the airbag cover 30 on the hinge portion 37 side which will be described later (portion on the lower surface side of the storage portion peripheral wall portion 24), and a distal end 39a of a door portion 39 to be described later of the airbag cover 30. Three are disposed on the side portion (the portion on the upper surface side of the storage portion peripheral wall portion 24), and one is disposed on each of the left and right sides of the vehicle.
[0026]
The main body portion 17 extends from the periphery of the opening 23a of the storage portion 23 and is formed in a substantially rectangular shape so as to widely cover the front side of the left and right knees K (KL / KR) of the driver MD seated. At the four corners of the periphery, attachment piece portions 21 for connection to the body 1 side of the vehicle are disposed. The vicinity of the upper edge side of the opening 23a in the main body portion 17 is provided with a concave portion 17a for projecting the lower surface 10a side of the column cover 10 to the rear side of the vehicle, and further corresponding to the curved state of the lower surface 10a. It is curved to protrude rearward. Ribs 18a for increasing the rigidity of the main body 17 are formed between the periphery of the opening 23a and the outer peripheral edge of the main body 17, and these ribs 18a are surfaces on the vehicle rear side and are airbag covers. The support part 18 is comprised so that the general part 31 mentioned later of 30 can be supported.
[0027]
A plurality of through-holes 19 that are opened in a substantially rectangular shape are formed on the periphery of the storage portion opening 23 a of the main body portion 17 so as to penetrate the front and back sides. These through holes 19 are respectively arranged on extension lines along the peripheral wall portions 24 of the hook locking collar portions 25a so that the attachment pieces 33 to be locked to the hooks 25 in the airbag cover 30 can be inserted. .
[0028]
A plurality of mounting holes 20 are formed on both the left and right sides of the main body 17 away from the storage portion 23 so as to penetrate the front and back. These attachment holes 20 serve as parts for attaching the airbag cover 30 to the knee panel 16 using heat caulking. That is, the airbag cover 30 has a distal end 32a in which a mounting leg portion 32 (to be described later) of the airbag cover 30 is inserted into each mounting hole 20, and the distal end 32a of each mounting leg portion 32 is expanded and melted. Is attached to the knee panel 16 together with the hook 25 so as not to be removed from the mounting hole 20.
[0029]
Further, each connecting piece portion 21 of the knee panel 16 is formed with a connecting hole 21a for fastening a bolt 29 (see FIG. 4) on the body 1 side, and on the body 1 side to which each connecting piece portion 21 is attached, the bracket 3・ 4 is arranged. These brackets 3 and 4 constitute an impact energy absorber, and when an impact force to the front side acts on the knee panel 16, the brackets 3 and 4 are plastically deformed to absorb the energy of the impact force to the front side. Become. The brackets 3 and 3 are connected to an instrument panel reinforcement 2 on the body 1 side, and the brackets 4 and 4 are connected to a center brace, a front body pillar, etc. (not shown) on the body 1 side.
[0030]
In the embodiment, the case where the knee panel 16 including the main body portion 17 and the storage portion 23 is integrally formed by pressing is shown. However, the knee panel 16 is formed by appropriately welding sheet metal. Also good.
[0031]
The airbag cover 30 is formed of a thermoplastic elastomer such as polyolefin, and has an outer shape larger than the outer shape of the knee panel 16 so as to cover the vehicle rear side of the knee panel 16 as shown in FIGS. It is configured.
[0032]
The airbag cover 30 is disposed on the lower panel 12b side of the peripheral edge of the column cover 10 in the instrument panel 12 including the upper panel 12a and the lower panel 12b, and covers the lower peripheral edge of the column cover 10 protruding from the instrument panel 12. . Therefore, the airbag cover 30 includes a recessed portion 30d that is recessed downward so that the column cover 10 protrudes rearward in the vicinity of the center when viewed from the vehicle rear side, and the upper edge side is provided below the recessed portion 30d. A raised portion 30c that is curved toward the vehicle rear side corresponding to the curved surface on the cover lower surface 10a side is disposed, and a flat plate-like portion 30a that extends so as to cover both the left and right sides of the knee panel main body portion 17 on both the left and right sides of the raised portion 30c. 30b is disposed and configured.
[0033]
The airbag cover 30 includes a door portion 39 that covers the opening 23 a of the knee panel storage portion 23, and a general portion 31 that covers the vehicle rear side of the knee panel main body portion 17.
[0034]
The door portion 39 is disposed on the lower side of the raised portion 30c and is formed in a substantially rectangular plate shape that is slightly larger than the opening 23a. A thin fracture target portion 35 connected to the general portion 31 is formed so as to open by opening. The planned fracture portion 35 is formed by providing a continuous or intermittent groove on the front surface of the vehicle so that the door portion 39 is easily broken when pushed by the inflating airbag 46. .
[0035]
In addition, a hinge portion 37 that is the center of rotation of the door portion 39 when the planned break portion 35 is broken and the door portion 39 opens is formed on the lower edge side of the door portion 39. The hinge portion 37 is an integral hinge, and has a thickness that does not break, and is thinner than the general portion 31 and the door portion 39.
[0036]
A plurality of attachment pieces 33 penetrating each through hole 19 in the main body portion 17 of the knee panel 16 are provided on the vehicle front side in the vicinity of the entire periphery of the storage portion opening 23a in the general portion 31. Each mounting piece 33 has a substantially rectangular plate shape. Each attachment piece 33 is formed with a locking hole 33a that opens in a rectangular shape for locking the periphery to the locking collar 25a of the hook 25.
[0037]
In addition, a plurality of mounting legs 32 are formed at predetermined positions of the general portion 31 around the peripheral edges of the mounting holes 20 in the main body portion 17 of the knee panel 16 to be locked by heat caulking. As shown in FIGS. 6 and 10, each mounting leg 32 is shaped like a round bar that can pass through the mounting hole 20 in the state before heat caulking, and is crushed after heat caulking as shown in FIGS. A portion 32a is provided at the tip, and a base portion 32b such as a columnar shape or a cross-sectional shape that contacts the knee panel body portion 17 at the periphery of the mounting hole 20 when the head 32a is fixed by heat caulking is provided on the base portion side. Has been.
[0038]
As shown in FIGS. 1 to 3, the inflator 41 is configured as a cylinder type configured to be able to discharge an expansion gas G by inputting an electric signal, and a cylindrical main body portion 41a having a gas discharge port 41b is provided. The male screw part 41c protrudes from one end of the main body part 41a. As described above, the inflator 41 is inserted into the knee panel storage portion 23 from the attachment hole 27 and screwed into the male screw portion 41c protruding from the attachment hole 28, whereby the male screw portion in the main body portion 41a. The end surface on the 41c side is pressed against the peripheral edge of the mounting hole 28 of the storage portion 23, and the outer peripheral surface of the main body portion 41a away from the male screw portion 41c is supported by the inner peripheral surface of the mounting hole 27. It is housed and held inside. Note that the inflator 41 passes through attachment holes 47a and 47b, which will be described later, of the airbag 46 when stored in the storage unit 23.
[0039]
The inflator 41 is operated by inputting an electric signal from a control device for operating an airbag device (not shown) mounted on the steering wheel 6 simultaneously with the steering wheel airbag device. A connector 43 to which a lead wire 44 connected to an airbag operating circuit is connected is disposed on the end surface of the main body 41a that protrudes from the storage portion 23.
[0040]
The airbag 46 is formed from a flexible woven fabric such as polyester or polyamide, and is configured as a substantially rectangular plate as shown in FIGS. Yes. In the case of the embodiment, the airbag 46 is configured by two woven fabrics, each having a substantially rectangular column cover 10 side wall portion 47 and a driver MD side wall portion 48. It is formed by sewing the peripheral edges together.
[0041]
Two attachment holes 47 a and 47 b are formed on the lower side of the column cover side wall 47. The mounting hole 47a is configured to have an inner diameter dimension substantially equal to the outer diameter dimension of the main body section 41a so that the main body section 41a of the inflator 41 can be inserted. The mounting hole 47b has an inner diameter dimension smaller than the outer diameter dimension of the main body section 41a. The male screw portion 41c can be inserted. In the airbag 46, the inflator main body 41a is inserted into the mounting hole 47a, the male screw portion 41c is inserted into the mounting hole 47b, and the inner peripheral surface of the mounting holes 47a and 47b is connected to the main body 41a and the male screw portion of the inflator 41. It is attached to the knee panel 16 by using an inflator 41 that is supported by 41c and stored in the storage unit 23.
[0042]
Further, the driver side wall 48 includes a lower central portion 48b that coincides with the position on the vehicle rear side at the position where the inflator 41 is disposed, and is flattened with the central portion 48a near the center in the left-right direction of the airbag 46. The left and right connecting portions 48c and 48c in the vicinity of the central portion 48a connected to the central portion 48a and on the center side of the left and right edges 46a and 46b of the airbag 46 in the state are configured.
[0043]
In the airbag 46 of the embodiment, the lower inflating portion 50 on the side where the inflator 41 is accommodated and the upper inflating portion above the lower inflating portion 50 so as to be divided vertically at the position where the tether 53 described later is disposed. And an inflating part 51. The lower inflating portion 50 protrudes from the opening 23a of the knee panel storage portion 23 toward the vehicle rear side as a portion on the upstream side of the inflation gas G, and the vehicle rear side surface of the general portion 31 in the airbag cover 30 at the periphery of the opening 23a. In addition, it is possible to cover the front side of the knee K (KL / KR) of the driver MD. The upper expansion portion 51 communicates with the lower expansion portion 50 as a downstream portion of the expansion gas G, and protrudes upward from the lower expansion portion 50 along the lower surface 10a of the column cover 10 so as to open. It is possible to cover at least the vicinity of the upper end 10b on the column cover lower surface 10a side from the surface on the vehicle rear side of the general portion 31 in the airbag cover 30 at the periphery of 23a. In the case of the embodiment, the lower inflating portion 50 at the time of deployment and inflating is such that the width dimension in the left-right direction is larger than the opening 23a so that both the knees KL and KR of the driver MD can be protected with a margin. Is set.
[0044]
Further, as shown in FIGS. 7 and 8, the column cover side and the driver side wall portions 47 and 48 are connected to each other in the airbag 46, so that the lower inflating portion 50 and the upper inflating portion 51 are in the expanded state. Tethers 52 and 53 are disposed as thickness regulating means for allowing the airbag 46 to smoothly enter between the knee K of the driver MD and the column cover lower surface 10a with a constant thickness dimension. The tethers 52 and 53 are formed of a flexible cloth material and are sewn to the wall portions 47 and 48 in the same manner as the wall portions 47 and 48 of the airbag 46. On the upper side of the arrangement portion 41, they are juxtaposed substantially in parallel with the left-right direction of the vehicle, and the left and right ends of the airbag 46 are separated from the left and right ends 46 a and 46 b of the airbag 46. The tether 53 is arranged as a thickness regulating means, and at the same time, the inflation gas G is discharged from the inflator 41 while directing the inflation gas G toward the left and right edges 46a and 46b of the airbag 46. It also plays a role as a gas flow guide for guiding to the upper expansion part 51.
[0045]
That is, the tether 53 disposed in the left-right direction of the vehicle closes the upper side of the inflator 41, between the left end 53a of the tether 53 and the airbag left edge 46a, the right end 53b of the tether 53, and the airbag right edge 46b. And when the inflation gas G is caused to flow through the airbag upper inflating portion 51 as the downstream portion, the air bag lower inflating portion 50 as the upstream portion Thus, the expansion gas G discharged from the inflator 41 is arranged to flow upward while moving in the left-right direction.
[0046]
Furthermore, in the airbag 46 of the embodiment, the lower inflatable portion 50 is in the air bag cover at the opening 40 when the door portion 39 is opened before the upper inflatable portion 51 completes the deployment and inflation at the initial stage of deployment and inflation. It is folded so that the left and right edges of 30 can be covered widely. In the case of the embodiment, the airbag 46 is folded through the following vertical folding process and horizontal folding process.
[0047]
As shown in FIGS. 9A to 9D, the vertical folding process causes the left and right edges 46 a and 46 b to approach the central portion 48 a side in a state where the driver side wall 48 is applied to the column cover side wall 47 and flattened. Is folded to a width dimension B1 in the left-right direction that can be stored in the storage portion 23. In particular, the folding portions 57 and 57 on the left and right edges of the airbag 46 are arranged on the driver side wall portion 48. The airbag 46 is vertically folded so as to be arranged on the column cover side wall 47 side of the left and right connecting portions 48c and 48c. The folding portions 57 and 57 on the left and right edges of the airbag 46 in the vertical folding process can be exemplified by accordion folding or roll folds in which the left and right edges 46a and 46b are wound around the column cover side wall 47.
[0048]
Further, the horizontal folding process is a process performed after the vertical folding process, and as shown in FIGS. 9D and 9E, the airbag upper edge 46c after the vertical folding process is brought closer to the arrangement position side of the inflator 41. In this process, the folded portion 58 is formed by being folded horizontally, and is folded to a thickness dimension in the vertical direction that can be stored in the storage portion 23.
[0049]
Next, the mounting of the airbag device S on a vehicle will be described. First, the airbag 46 is folded. In the case of the embodiment, the airbag 46 is folded in two steps, that is, a vertical folding step and a horizontal folding step, as shown in FIGS.
[0050]
Then, in the longitudinal folding process, as shown in FIG. 9A, from the state where the driver side wall portion 48 is applied to the column cover side wall portion 47 and flattened, the left and right edges 46a of the airbag 46 as shown in FIG. 9B. The left and right edges 46a and 46b are folded toward the column cover side wall 47 so that 46b approaches the central portion 48a of the driver side wall 48. Further, as shown in FIG. 9C, both the edges 55 and 56 are respectively column cover so that the left and right edges 55 and 56 after folding in the airbag 46 are brought close to the central portion 48a of the driver side wall 48. Folding portions 57 and 57 are formed by folding toward the side wall 47 side. Next, as shown in FIG. 9D, in order to correspond to the storage width dimension of the storage portion 23 in the left-right direction, the folding portions 57 and 57 are made to be column cover side wall portions at the left and right connecting portions 48c and 48c of the driver side wall portion 48. In the state of being arranged on the 47 side, the vehicle is folded so as to be placed on the outer surface (on the vehicle rear side and on the driver side) in the central portion 48a of the driver side wall 48, and the vertical folding process is completed.
[0051]
In the horizontal folding step after the vertical folding step, as shown in FIGS. 9D and 9E, the airbag 46 after the vertical folding is folded so as to be rolled from the upper edge 46c toward the column cover side wall 47, The folding part 58 is formed, and the horizontal folding process is completed according to the storage thickness dimension of the storage part 23 in the vertical direction, and the folding operation of the airbag 46 is completed.
[0052]
After the airbag 46 is folded, the airbag 46 is wrapped with a ruptureable wrapping film (not shown) for preventing collapse so that the mounting holes 27 and 47a and the mounting holes 28 and 47b are aligned with each other. The airbag 46 is stored in the storage unit 23. Note that the wrapping film at the mounting holes 47a and 47b is broken.
[0053]
Thereafter, the male screw portion 41c is inserted into the airbag 46 stored in the storage portion 23 from the mounting holes 27 and 47a side, and further protruded from the mounting holes 47b and 28, and the protruding male screw portion 41c has a nut. If the end face on the male screw part 41c side of the main body part 41a is pressed against the inner peripheral surface of the storage part 23 with the peripheral edge of the attachment hole 47a of the airbag 46 interposed therebetween, the inflator 41 and the airbag 46 are connected. It can be attached to the storage unit 23.
[0054]
Then, the airbag cover 30 is attached to the knee panel 16. As shown in FIGS. 10 and 11, first, the attachment pieces 33 are inserted into the respective through holes 19 from the rear side of the knee panel 16 and the corresponding attachment holes 20 are supported. The round bar-shaped head portion 32a of the mounting leg portion 32 to be inserted is inserted.
[0055]
At this time, each attachment piece 33 interferes with the curved guide surface 25b on the rear side of the vehicle in the hook 25a of the hook 25 as shown by a two-dot chain line in FIGS. Thus, when the locking hole 33a is disposed at the position of the locking hook 25a, it is restored and the locking hook 25a is inserted into the locking hole 33. That is, each attachment piece 33 is simply passed through the through-hole 19 so that the peripheral edge of the locking hole 33 is automatically locked to the locking collar portion 25a.
[0056]
Further, the head 32 a of the mounting leg 32 protruding from each mounting hole 20 is heated and expanded in diameter with the base 32 b of the locking leg 32 being in contact with the periphery of each mounting hole 20. Thus, the knee panel body 17 is locked to the periphery of the mounting hole 20 on the front surface of the vehicle. As a result, the airbag cover 30 can be attached to the knee panel 16, and the airbag assembly SA can be formed.
[0057]
In such an airbag assembly SA, if each connecting piece portion 21 of the knee panel main body 17 is connected to the brackets 3 and 4 on the body 1 side by bolts 29 and connected, the airbag device for knee protection is attached to the vehicle. S can be mounted.
[0058]
After the airbag device S is mounted on the vehicle, the lead wire 44 is connected to the airbag operation circuit, and the upper panel 12a and the lower panel 12b of the instrument panel 12 and the under cover 14 (see FIGS. 1 and 2) are attached to the vehicle. Will be installed.
[0059]
If a predetermined electrical signal is input to the inflator 41 after the airbag device S is mounted on the vehicle, the inflation gas G is discharged from the gas discharge port 41b, and the airbag 46 is expanded to wrapping (not shown). The film is broken and the door portion 39 of the airbag cover 30 is pushed to break the portion 35 to be broken, and the door portion 39 is opened with the hinge portion 37 as the center of rotation. As a result, the opening of the storage portion 23 is opened. From 23a, through the opening 40 of the airbag cover 30 formed by opening the door portion 39, it protrudes to the vehicle rear side, and further, along the column cover lower surface 10a, while eliminating lateral folding and vertical folding, It expands and expands greatly upward (see FIGS. 12A and 13B).
[0060]
When the airbag 46 is deployed and inflated, the airbag cover 30 stores the attachment pieces 33 arranged at a plurality of locations near the periphery of the storage portion opening 23a in the general portion 31 through the through holes 19 of the knee panel 16. Since it is attached to the portion 23, the portion of the general portion 31 in the vicinity of the periphery of the storage portion opening 23a, such as the planned break portion 35 and the hinge portion 37, is difficult to move with respect to the storage portion 23, and the pressing force of the airbag 46 is accurate. Acting on the planned fracture portion 35, the planned fracture portion 35 is smoothly broken. Further, the hinge portion 37 serving as the rotation center at the time of opening is also difficult to move with respect to the storage portion 23, and the opening operation of the door portion 39 can be stabilized. As a result, even if the airbag cover 30 is formed of a synthetic resin such as a thermoplastic elastomer, the door portion 39 pressed by the airbag 46 is smoothly opened.
[0061]
Therefore, in the knee protection airbag device S of the embodiment, the airbag cover 30 having the door part 39 integrated with the knee panel 16 disposed in a wide area on the front side of the knee K of the seated occupant MD is provided. Even if attached, the door part 39 pushed by the airbag 46 can be opened smoothly.
[0062]
In order to ensure smooth breakage of the planned breakage portion 35 and smooth opening operation of the door portion 39, at least at the periphery of the opening 23 a on the tip 39 a side away from the hinge portion 37 of the door portion 39 to be opened. An attachment piece 33 that passes through the knee panel main body portion 17 and is attached to the storage portion 23 may be disposed in the vicinity of the planned fracture portion 35 and in the vicinity of the hinge portion 37.
[0063]
However, as in the embodiment, if the mounting portion 33 is disposed around the entire periphery of the substantially rectangular opening 23 a in the storage portion 23, the smooth breakage of the planned breakage portion 35 and the stable door portion 39 are achieved. Can be secured.
[0064]
Moreover, in the case of embodiment, although the case where the door part 39 of one door was opened and the airbag 46 protruded from the opening 40 was shown, two door parts of the double opening type like a kannon door Thus, the opening 23a of the storage portion 23 may be covered. In this case, the planned fracture portion is arranged in an “H” shape or an “E” shape when viewed from the vehicle rear side. In these cases, if the portion to be broken is formed in an “H” shape, the hinge portion is disposed so as to tie the ends of the vertical bar portions on both the left and right sides of the “H” shape, and to be broken If the portion is formed in an “E” shape, it is arranged and configured so as to connect the ends of the horizontal bar portions on the upper and lower sides of the “E” character. In these cases, it is desirable to dispose the attachment piece at least on the periphery of the opening of the storage portion in the vicinity of the hinge portion.
[0065]
Further, the mounting piece 33 arranged on the periphery of the opening 23a opened in a substantially rectangular shape has a shape and the like appropriately increased if the mounting strength can be secured when it is disposed on one side of the opening shape of the opening 23a. (Refer to the side of the wall portions 24a and 24b), or a plurality (see the upper edge side and the lower edge side of the periphery of the opening 23a).
[0066]
In addition, each attachment piece 33 of the airbag cover 30 of the embodiment is only passed through the through hole 19 at the periphery of the storage portion opening 23a in the knee panel 16, and the body portion 17 of the knee panel 16 has a small outer shape. Therefore, even if both knees K (KL and KR) of the occupant MD interfere with each other in the non-inflated state of the airbag 46, it is possible to receive the left and right knees KL and KR in a wide area, smoothly. The brackets 3 and 4 as the impact energy absorber can be deformed. Of course, in this embodiment, the main body portion 17 of the knee panel 16 can support the vehicle front side of the airbag 46 that has been inflated with the general portion 31 of the airbag cover 30 interposed therebetween, thereby completing the deployment and inflation. The airbag 46 is stably supported by the knee panel body 17.
[0067]
Further, in the knee protection airbag device S of the embodiment, the airbag 46, the inflator 41, the airbag cover 30, and the knee panel 16 can be integrated in advance to form the airbag assembly SA. Therefore, if the airbag assembly SA is formed in advance, the airbag 46 and the like can be transported and stored in an assembled state, and the handling of each member until it is attached to the vehicle becomes easy. .
[0068]
Furthermore, in the embodiment, each hook 25 of the storage portion 23 is inserted into the locking hole 33a of each mounting piece 33 of the airbag cover, and the mounting piece 33 is locked by the locking hook portion 25a of each hook 25. By doing so, the attachment of the attachment piece 33 to the storage portion 23 can be completed, and therefore the number of steps and cost for attaching the airbag cover 30 to the knee panel 16 can be reduced. In particular, in the embodiment, simply attaching each attachment piece 33 to the through hole 19 causes the attachment pieces 33 to bend automatically, and the peripheral edge of the engagement hole 33 is engaged with the engagement collar portion 25a. Therefore, the number of mounting steps can be further reduced. Incidentally, if this point is not taken into account, the attachment pieces 33 may be attached to the storage portion 23 by using bolts, nuts, rivets or the like without providing the hooks 25.
[0069]
In the embodiment, in the initial stage of the airbag 46 that is deployed and inflated, first, as shown in FIG. As shown in FIG. 12B, the upper inflating portion 51 is inflated and inflated as shown in FIG. 12B. That is, the airbag 46 can cover the front side of both the knees KL and KR of the driver MD in a wide range in the left-right direction by suppressing the protrusion to the driver MD as much as possible in the initial stage of deployment and inflation. Even if the forward movement of both knees K (KL and KR) is quick, it becomes possible to protect quickly.
[0070]
In the embodiment, the airbag device S disposed on the front side of the vehicle of the driver MD is taken as an example to protect the knee K of the driver MD. However, as shown in FIG. The airbag apparatus S may be disposed at a position on the front side of the vehicle of the occupant MP seated in the passenger seat so as to protect both knees K (KL, KR) of the passenger occupant MP seated in the passenger seat.
[Brief description of the drawings]
FIG. 1 is a schematic longitudinal sectional view in the vehicle front-rear direction showing a use state of a knee protecting airbag device according to an embodiment of the present invention.
FIG. 2 is a schematic enlarged longitudinal sectional view of the knee protecting airbag device according to the embodiment of the present invention in the vehicle front-rear direction.
3 is a cross-sectional view taken along the line III-III in FIG.
FIG. 4 is a schematic front view showing the use state of the knee protecting airbag device of the embodiment as seen from the vehicle rear side.
FIG. 5 is an exploded front perspective view of a knee panel and an airbag cover as plate-like members used in the embodiment.
FIG. 6 is an exploded rear perspective view of a knee panel and an airbag cover as plate-like members used in the embodiment.
FIG. 7 is a front view of the airbag used in the embodiment.
8 is a schematic cross-sectional view of the VIII-VIII portion of FIG.
FIG. 9 is a schematic view showing folding of the airbag of the embodiment.
FIG. 10 is a view showing a state in which the airbag cover of the embodiment is attached to a knee panel as a plate-like member.
11 is a view showing a state in which the airbag cover of the embodiment is attached to a knee panel as a plate-like member, and shows a state after FIG.
FIG. 12 is a schematic front view seen from the rear side of the vehicle, explaining deployment and inflation of the airbag of the embodiment.
FIG. 13 is a schematic longitudinal sectional view of a state along the vehicle front-rear direction showing a state in which the airbag of the embodiment has been deployed and inflated.
FIG. 14 is a schematic front view seen from the vehicle rear side showing a state in which the knee protection airbag device according to the embodiment of the present invention is arranged on the vehicle front side of the passenger seat.
[Explanation of symbols]
16 (plate member) knee panel,
23. Storage section,
23a ... opening,
25 ... Hook,
30 ... Airbag cover,
35 ... planned to break,
37 ... Hinge part,
39 ... the door,
41 ... Inflator,
46 ... Airbag,
M ... (MD ... Driver, MP ... Passenger seat passenger) Crew,
S: Air bag device for knee protection.

Claims

A folded plate-protecting airbag and an inflator that supplies inflation gas to the airbag are stored in a plate-like member disposed on the front side of the seated occupant's knee, and the stored airbag is A knee protection airbag device constructed by attaching and covering an airbag cover that protrudes,
The plate-like member is
By opening the rear side, a housing portion of the box-shaped with a bottom for accommodating said said airbag inflator,
A plate-like body formed so as to extend from the periphery of the opening of the storage portion, and is attached to the vehicle body side, and a main body portion capable of supporting the vehicle front side of the airbag when the inflation is completed;
Composed of
The airbag cover is made of synthetic resin,
A door portion that covers the opening of the storage portion and is pushed by the airbag at the time of inflation to open a thin rupture portion that is thin at the periphery, and
A hinge part disposed around the door part and serving as a center of rotation of the door part at the time of opening;
A general portion that is disposed around the door portion with the planned break portion and the hinge portion interposed therebetween, and covers the vehicle rear side of the periphery of the storage portion in the plate member;
And configured with
In a plurality of locations in the vicinity of the opening periphery of the storage section in the general section, mounting pieces that are attached to the storage section are arranged, and configured.
In the plate-like member, a portion of the peripheral edge of the opening of the housing portion of the main body portion, the mounting piece can be inserted a plurality of through holes, that are formed knee protecting airbag device according to claim .

Each attachment piece of the airbag cover is configured to include a locking hole, and the storage portion includes a plurality of hooks that can be inserted into the locking hole to lock the mounting pieces. The knee protection airbag device according to claim 1, wherein the knee protection airbag device is provided.

The hook is disposed so as to be reversed to the side away from the opening of the storage portion, and the locking collar portion inserted into the locking hole, and the mounting piece is elastically deformed so as to be separated from the storage portion. And a guide surface that guides possible,
When the mounting piece is inserted into the through hole, the mounting piece interferes with the guide surface and elastically deforms away from the storage portion, and the locking hole is disposed at the position of the locking hook portion. 3. The knee protection airbag device according to claim 2, wherein the knee protection airbag device is configured to be restored and to insert the locking collar portion into the locking hole.

The airbag apparatus for knee protection according to any one of claims 1 to 3, wherein the plate-like member is made of sheet metal.

The periphery of the body portion, the knee according to any one of claims 1 to 4 mount piece for mounting the plate-like member to the body side of the vehicle, characterized in that it is a configuration that is disposed Protective airbag device.

The knee protection airbag device according to any one of claims 1 to 5, wherein the main body portion includes a support portion capable of supporting a general portion of the airbag cover.