JP3861525B2

JP3861525B2 - Auto body front structure

Info

Publication number: JP3861525B2
Application number: JP25467699A
Authority: JP
Inventors: 学佐藤
Original assignee: Nissan Motor Co Ltd
Current assignee: Nissan Motor Co Ltd
Priority date: 1999-09-08
Filing date: 1999-09-08
Publication date: 2006-12-20
Anticipated expiration: 2019-09-08
Also published as: JP2001071945A

Description

【０００１】
【発明の属する技術分野】
本発明は自動車の車体前部構造、とりわけ、フロントコンパートメントの左右両側部に配設されて車体前部の前後方向骨格部材を構成するフロントサイドメンバの配設構造に関する。
【０００２】
【従来の技術】
フロントコンパートメントの左右側壁を構成するフードリッジパネルの下側部には、車体前部の前後方向骨格部材を構成する閉断面構造のフロントサイドメンバを配設し、該フロントサイドメンバの後端部を車室とフロントコンパートメントとを隔成するダッシュパネルに結合して、車体前部の剛性を確保するようにしている（特開平１０−２６４８６２号公報参照）。
【０００３】
【発明が解決しようとする課題】
車両の前面衝突時の衝突エネルギー吸収量はフロントコンパートメントの前後方向の潰れストロークにほぼ比例し、該フロントコンパートメントの潰れストロークを拡大するためには、フロントサイドメンバを前端側から順序よく潰れ変形させる必要がある。
【０００４】
このようにフロントサイドメンバを前端側から順序よく潰れ変形させるためには、該フロントサイドメンバの後半部の曲げ剛性，強度がフロントサイドメンバの前半部よりも大きくなければならないし、また、フロントサイドメンバとダッシュパネルとの結合剛性を高めて、該フロントサイドメンバの圧潰反力を高く維持できるように構成しなければならないが、これは結果的にはフロントサイドメンバの潰れ変形をほぼその前半部にとどめてしまうことになりかねない。
【０００５】
そこで、本発明はフロントサイドメンバの後半部分の強度・剛性を確保することができ、かつ、車両の前面衝突時にはフロントコンパートメントの前後方向の潰れ変形ストロークを拡大できて、衝突エネルギー吸収量を増大することができる自動車の車体前部構造を提供するものである。
【０００６】
【課題を解決するための手段】
請求項１の発明にあっては、ダッシュパネルにより車室の前側に隔成されたフロントコンパートメントの左右両側部に前後方向に延在するフロントサイドメンバを、左右メンバ間のスパンが前端側からダッシュパネル側に至るに従って小さくなる平面ハの字状に配置する一方、ダッシュパネルに、前方に張り出し、かつ、前端側に対してダッシュパネル側の閉断面積をフロントサイドメンバ後端部の車幅方向内側への回転移動を許容し得るように拡大したメンバ連結部材を結合配置すると共にその前端部に回動支点を設定し、該メンバ連結部材に前記フロントサイドメンバの後端部を前記回動支点を中心に水平方向に回動可能に抱持固定すると共に、ダッシュパネルにフロントサイドメンバの後端上縁に係合してフロントサイドメンバ後端の上方への移動を拘束し、かつ、水平方向の回転をガイドするストッパ縁を設けたことを特徴としている。
【０００７】
請求項２の発明にあっては、請求項１に記載のメンバ連結部材の車幅方向内側の側壁に、回動支点付近からダッシュパネル側に至るに従ってフロントサイドメンバの車幅方向内側の側壁から離間する回動規制用の斜面部を設けたことを特徴としている。
【０００８】
請求項３の発明にあっては、請求項１，２に記載のメンバ連結部材の上壁の後側部に、フロントサイドメンバの車幅方向内側の上縁に係合する位置決め段部を形成したことを特徴としている。
【０００９】
請求項４の発明にあっては、請求項１〜３に記載の回動支点をメンバ連結部材に固設したサスペンションマウントボルトと同軸心上に設けると共に、フロントサイドメンバを該回動支点の近傍でのみメンバ連結部材と接合固定したことを特徴としている。
【００１０】
請求項５の発明にあっては、請求項１〜４に記載のメンバ連結部材の車幅方向内側の側壁に、回動支点付近でフロントサイドメンバの車幅方向内側の側壁に当接する凹設部を前後方向に形成したことを特徴としている。
【００１１】
請求項６の発明にあっては、請求項１〜５に記載のメンバ連結部材を、ダッシュパネルに結合されて前方に張り出し、かつ、前端部下面にサスペンションマウントボルトを固設したアーム部を備え、該アーム部の前端部にフロントサイドメンバの略下半部に嵌合する受容部と、回動支点を設けたロア部材と、
上壁と車幅方向内側の側壁とで断面逆Ｌ字状に形成されて、前端部をフロントサイドメンバとの嵌合部とし、後端をダッシュパネルに接合すると共に前記側壁をロア部材に接合したアッパ部材と、の２部品で構成したことを特徴としている。
【００１２】
請求項７の発明にあっては、請求項６に記載のメンバ連結部材の少くともロア部材を軽量金属材料で鋳造成形して、サスペンションマウントボルトを鋳ぐるみ固定し、該サスペンションマウントボルトの鋳ぐるみ固定部分を回動支点としたことを特徴としている。
【００１３】
請求項８の発明にあっては、請求項１〜７に記載の回動支点を上向きに突出するロケートピンで構成する一方、フロントサイドメンバの下壁には該ロケートピンが挿入係合するロケート孔を設けたことを特徴としている。
【００１４】
請求項９の発明にあっては、請求項１〜８に記載のダッシュパネルを軽量金属材料で閉断面構造に車幅方向に押出成形する一方、フロントサイドメンバの少くとも後側部を軽量金属材料で一定の閉断面形状に押出成形したことを特徴としている。
【００１５】
請求項１０の発明にあっては、請求項１〜９に記載のフロントサイドメンバをジョイント部材で連結したフロントメンバとリヤメンバとで構成し、少くともフロントメンバを断面円形に形成して左右のメンバ前端部間をクロスメンバで結合したことを特徴としている。
【００１６】
請求項１１の発明にあっては、請求項１０に記載のクロスメンバのフロントメンバとの結合部分に、フロントバンパーのバンパーステイをフロントメンバと同軸線上に支持するステイ連結部を設けたことを特徴としている。
【００１７】
請求項１２の発明にあっては、請求項１１に記載のバンパーステイをステイ連結部に水平方向に回動可能に連結したことを特徴としている。
【００１８】
【発明の効果】
請求項１に記載の発明によれば、フロントサイドメンバをダッシュパネルに結合したメンバ連結部材は、その前端側に対してダッシュパネル側の閉断面積を拡大してフロントサイドメンバ後端部のダッシュパネルとの結合部分の剛性を高めてあり、しかも、左右のフロントサイドメンバを平面ハの字状に配置して回動支点を中心に水平方向に回動可能としてあるから、車両の前面衝突時にフロントサイドメンバの圧潰反力を高く維持させて前半部分を前端側から順序よく潰れ変形させると共に、フロントサイドメンバを回動支点を中心にハの字が開く方向に回転させて、フロントコンパートメントの潰れスペースを増大させることができる。
【００１９】
従って、フロントサイドメンバの前半部分を完全に圧潰させたのちさらに該フロントコンパートメントの潰れ変形を継続させて潰れ変形ストロークを拡大できるため、衝突エネルギー吸収量を格段に増大することができる。
【００２０】
しかも、前記フロントサイドメンバの回転時にはダッシュパネルのストッパ縁によって、該フロントサイドメンバの後端縁の上方への移動を拘束すると共に、水平方向の回転をガイドするため、フロントサイドメンバの回転軌跡を限定して回転モードを安定させることができて、フロントコンパートメントの潰れスペースの増大化を極めて安定的に実現することができる。
【００２１】
請求項２に記載の発明によれば、請求項１の発明の効果に加えて、フロントサイドメンバが水平方向に回転した際に、メンバ連結部材の車幅方向内側の側壁に設けた斜面部でこのフロントサイドメンバの回転を規制して、該フロントサイドメンバのハの字状の開き角度を所要角度に維持することができ、従って、フロントサイドメンバの過度の開き方向の回転による圧潰反力特性の低下を回避することができる。
【００２２】
請求項３に記載の発明によれば、請求項１，２の発明の効果に加えて、フロントサイドメンバはその後端部の車幅方向内側の上縁がメンバ連結部材の上壁の位置決め段部に係合して、所定の平面ハの字状の開き角度に適正に組付けることができるため、設計通りのフロントサイドメンバの潰れ特性を得ることができる。
【００２３】
請求項４に記載の発明によれば、請求項１〜３の発明の効果に加えて、回動支点をサスペンションマウントボルトの同軸心上に設けてあるため、該回動支点を中心とするフロントサイドメンバの回転支持に、サスペンションメンバ自体の剛性・強度を寄与させることができ、該回動支点の支持剛性を高めてフロントサイドメンバの回転を安定させることができる。
【００２４】
また、フロントサイドメンバはこの回動支点の近傍でのみメンバ連結部材に接合して、回動支点から後方の部分は該メンバ連結部材と非接合状態としてあるため、前面衝突時にフロントサイドメンバを確実に回転作動させることができる。
【００２５】
請求項５に記載の発明によれば、請求項１〜４の発明の効果に加えて、回動支点付近でフロントサイドメンバの車幅方向内側の側壁にメンバ連結部材の車幅方向内側の側壁に設けた凹設部が当接して、該回動支点付近の断面係数を大きくできることに加えて、メンバ連結部材の側壁の面剛性を高められるため、フロントサイドメンバの左右方向の支持剛性・強度を高めることができる。
【００２６】
請求項６に記載の発明によれば、請求項１〜５の発明の効果に加えて、フロントサイドメンバの組付けに際しては、該フロントサイドメンバの後端部をメンバ連結部材のロア部材の受容部上に嵌合，載置し、その上方もしくは側方よりアッパ部材を嵌合することによって該メンバ連結部材に容易に組付けることができて、ロボットによる自動組付けが可能となり、また、これらロア部材，アッパ部材との嵌合によってフロントサイドメンバの位置決めと仮保持を行えるので、専用の車体組付治具設備が不要となり、大幅なコストダウンを実施することができる。
【００２７】
請求項７に記載の発明によれば、請求項６の発明の効果に加えて、メンバ連結部材のロア部材を鋳造成形してサスペンションマウントボルトを鋳ぐるみ固定し、この鋳ぐるみ固定部分を回動支点としてあるため、これらサスペンションマウントボルトおよび回動支点を位置決め治具等を用いて精度出しを行うことなく容易に設定することができる。
【００２８】
請求項８に記載の発明によれば、請求項１〜７の発明の効果に加えて、回動支点をロケートピンで構成し、フロントサイドメンバの下壁にはロケート孔を設けてあるので、該フロントサイドメンバの組付時にはこれらロケートピンとロケート孔とを挿入，係合することによってフロントサイドメンバの前後方向の位置決めを行え、従って、組付作業性をより一層向上することができる。
【００２９】
請求項９に記載の発明によれば、請求項１〜８の発明の効果に加えて、フロントサイドメンバの少くとも後半部は一定の閉断面に押出成形してあるため曲げ剛性が高く、また、車両の前面衝突時に該フロントサイドメンバに作用する上下方向の曲げモーメントに対して、フロントサイドメンバの押出方向と直交する方向に押出成形されて曲げ剛性の高いダッシュパネルの曲げ方向で強度的に有利に受けて該上下曲げモーメントを吸収することができ、従って、フロントサイドメンバの折れ曲がりや、ダッシュパネルとの結合部分での折れ曲がりを生じることなく該フロントサイドメンバの前半部分の潰れ変形を適正に行わせることができる。
【００３０】
請求項１０に記載の発明によれば、請求項１〜９の発明の効果に加えて、フロントサイドメンバのフロントメンバを、単位ねじり角に対して大きなねじりトルクを吸収でき、かつ、ねじりによる断面変形が生じにくい円形断面に形成してあるから、車両の前面衝突時に左右のフロントサイドメンバ前端部間のスパンが拡大する際に、フロントメンバにねじり力が作用しても該フロントメンバを局部的な壁面座屈による折れ曲がりを生じさせることなく適正に潰れ変形させることができる。
【００３１】
請求項１１に記載の発明によれば、請求項１０の発明の効果に加えて、フロントバンパーのバンパーステイをステイ連結部でフロントメンバと同軸線上に支持してあるため、衝突入力をフロントメンバの中心軸に適正に作用させることができる。
【００３２】
請求項１２に記載の発明によれば、請求項１１の発明の効果に加えて、バンパーステイはステイ連結部に水平方向に回動可能としてあるから、車両の前面衝突時に左右のフロントサイドメンバ前端部間のスパンが拡大する際のクロスメンバ側部のねじれ回転を規制することがなく、前記スパン拡大作用を適正に行わせることができる。
【００３３】
また、フロントバンパーを衝突方向に向けることができて、フロントサイドメンバの軸線方向に適正に衝突入力を作用させることができる。
【００３４】
【発明の実施の形態】
以下、本発明の一実施形態を図面と共に詳述する。
【００３５】
図１，２において、１は車室Ｒの前方に図外のエンジン等のパワーユニットを搭載するフロントコンパートメントＦ・Ｃを隔成するダッシュパネルを示し、該ダッシュパネル１はアルミ合金等の軽量金属材料により閉断面構造に車幅方向に押出成形してある。
【００３６】
フロントコンパートメントＦ・Ｃの左右側部を隔成するフードリッジパネル２（図７〜９参照）の下端部に前後方向に沿って接合配置した左右のフロントサイドメンバ４は、左右メンバ間のスパンが前端側からダッシュパネル１側に至るに従って小さくなる平面ハの字状に配置してあり、それらの後端部はメンバ連結部材３を介して前記ダッシュパネル１に結合してある。
【００３７】
メンバ連結部材３は前端側に対してダッシュパネル１側の閉断面積を拡大してあって、該メンバ連結部材３をロア部材３Ａとアッパ部材３Ｂの２部品で構成してあり、これらは何れも前述と同様の軽量金属材料により鋳造成形してある。
【００３８】
ロア部材３Ａは１つのベース部５を共有して左右一体に成形してあり、ベース部５の前縁フランジ５ａの部分でダッシュパネル１に接合すると共に、該ベース部５の左右両側部に形成した位置決め部６にダッシュパネル１の左右両端部を嵌合係着した上で接合してある。
【００３９】
ロア部材３Ａはダッシュパネル１の前方に張り出すアーム部７を一体成形してあり、該アーム部７とアッパ部材３Ｂとで閉断面を構成している。
【００４０】
アーム部７の前端部にはフロントサイドメンバ４の後端部の略下半部の外形形状に見合った断面形状の受容部７ａを形成してあり、該受容部７ａにフロントサイドメンバ４の後端部の略下半部を嵌合，定置するようにしている。
【００４１】
また、アーム部７の前記受容部７ａのやや後方部位とベース部５には、下向きに突出するサスペンションマウントボルト８，９を鋳ぐるみ固定してあり、これらサスペンションマウントボルト８，９に跨って図５に示すようにサスペンションメンバ１０をそれぞれナット８ａ，９ａにより締結固定するようにしてある。
【００４２】
後側のサスペンションマウントボルト９の鋳ぐるみ固定部には、同軸心上にロケートピン１１を上向きに突出成形してあり、該ロケートピン１１を図５に示すようにダッシュパネル１の外壁に設けたロケート孔１２に挿入係合して、その上端に設けたねじ部１１ａにリテーナプレート１３を介して内壁上にナット１４により締結固定するようにしている。
【００４３】
前側のサスペンションマウントボルト８の鋳ぐるみ固定部には図３〜５および図９，１０に示すように、同軸心上に回動支点としてのロケートピン１５を上向きに突出成形してあり、該ロケートピン１５をフロントサイドメンバ４の後端部の下壁に設けたロケート孔１６に挿入係合して、フロントサイドメンバ４を該ロケートピン１５を回動中心として水平方向に回動可能としてある。
【００４４】
メンバ連結部材３のアッパ部材３Ｂは上壁３Ｂ₁と車幅方向内側の側壁３Ｂ₂とで断面逆Ｌ字状に形成してあり、前端部をフロントサイドメンバ４の上壁と車幅方向内側の側壁とに当接係合する嵌合部１７としてある。
【００４５】
このアッパ部材３Ｂは後端縁に形成したフランジ１８の部分でダッシュパネル１に接合固定し、そして、車幅方向内側の側壁３Ｂ₂の下縁部を前記アーム部７の車幅方向内側の側壁上縁部に重合して接合することによりメンバ連結部材３の側壁１９を構成するが、該側壁１９には前記ロケートピン１５で構成する回動支点付近からダッシュパネル１側に至るに従ってフロントサイドメンバ４の車幅方向内側の側壁から離間する回動規制用の斜面部１９ａを形成してある。
【００４６】
アッパ部材３Ｂの上壁３Ｂ₁の車幅方向外側の側縁には舌片２０を延設してあり、該舌片２０を図８に示すようにフードリッジパネル２に接合したクロージングプレート２ａの棚部上に接合固定してある。
【００４７】
また、この上壁３Ｂ₁の後側部にはフロントサイドメンバ４の車幅方向内側の上縁に係合する位置決め段部２１を形成してある。
【００４８】
この位置決め段部２１は上壁３Ｂ₁を部分的に凹設して形成しているが、下向きに突出するリブ突起で構成するようにしてもよい。
【００４９】
また、アッパ部材３Ｂの側壁３Ｂ₂には前記回動支点であるロケートピン１５付近でフロントサイドメンバ４の車幅方向内側の側壁に当接する凹設部２２を前後方向に形成してある。
【００５０】
フロントサイドメンバ４は前述のようにロケートピン１５とロケート孔１６とを係合させ、かつ、後端をダッシュパネル１に突き当ててメンバ連結部材３に水平方向に回動可能に抱持されるが、該フロントサイドメンバ４は前記回動支点であるロケートピン１５の近傍でのみメンバ連結部材３と溶接により接合固定され、該回動支点１５の後方からダッシュパネル１に至る部分間ではメンバ連結部材３と非接合状態にしてある。
【００５１】
一方、ダッシュパネル１の前面にはフロントサイドメンバ４の後端上縁に係合してフロントサイドメンバ４の後端の上方への移動を拘束し、かつ、水平方向の回転をガイドするストッパ縁２３を押出方向に形成してある。
【００５２】
フロントサイドメンバ４もアルミ合金等の軽量金属材料により一定の閉断面形状に押出成形されるが、本実施形態では円形断面のフロントメンバ４Ａと多角形断面のリヤメンバ４Ｂとに分割し、これら両者をジョイント部材２４で連結して構成している。
【００５３】
左右のフロントメンバ４Ａの前端部間は図１１，１２にも示すようにクロスメンバ２５で結合されるが、このクロスメンバ２５はその両側端部に連結メンバ２６を接続固定してあり、該連結メンバ２６に設けたソケット部２７にフロントメンバ４Ａの前端を嵌合して接続固定するようにしている。
【００５４】
連結メンバ２６のソケット部２７の前側にはステイ連結部２８を設けてあり、該ステイ連結部２８にフロントバンパー２９（図１，１１ではバンパーアーマチュアのみを示している）のバンパーステイ３０の後端部を挿入してフロントメンバ４Ａと同軸線上に支持して、図外のピン部材により水平方向に回動可能に連結してある。
【００５５】
図１中、３１はフロアパネルを示し、該フロアパネル３１も前述と同様の軽量金属材料により閉断面構造に前後方向に押出成形してある。
【００５６】
以上の実施形態の構造によれば、フロントサイドメンバ４をダッシュパネル１に結合したメンバ連結部材３は、その前端側に対してダッシュパネル１側の閉断面積を拡大してフロントサイドメンバ４の後端部のダッシュパネル１との係合部分の剛性を高めてあり、しかも、左右のフロントサイドメンバ４を平面ハの字状に配置して回動支点であるロケートピン１５を中心に水平方向に回動可能としてあるから、車両の前面衝突時にフロントサイドメンバ４の圧潰反力を高く維持させて前半部分を前端側から順序よく潰れ変形させると共に、図６の仮想線で示すようにフロントサイドメンバ４をロケートピン１５を中心にハの字が開く方向に回転させて、フロントコンパートメントＦ・Ｃの潰れスペースを増大させることができる。
【００５７】
従って、フロントサイドメンバ４の前半部分を完全に圧潰させたのちさらに該フロントコンパートメントＦ・Ｃの潰れ変形を継続させて潰れ変形ストロークを拡大できるため、衝突エネルギー吸収量を格段に増大することができる。
【００５８】
しかも、前記フロントサイドメンバ４の回転時にはダッシュパネル１のストッパ縁２３によって、該フロントサイドメンバ４の後端縁の上方への移動を拘束すると共に、水平方向の回転をガイドするため、フロントサイドメンバ４の回転軌跡を限定して回転モードを安定させることができて、フロントコンパートメントＦ・Ｃの潰れスペースの増大化を極めて安定的に実現することができる。
【００５９】
ここで、前記フロントサイドメンバ４の回転時には、メンバ連結部材３の車幅方向内側の側壁１９に設けた斜面部１９ａでこのフロントサイドメンバ４の回転を規制して、該フロントサイドメンバ４のハの字状の開き角度を所要角度に維持することができるため、フロントサイドメンバ４の過度の開き方向の回転による圧潰反力特性の低下を回避することができる。
【００６０】
この車両の前面衝突時にはフロントサイドメンバ４に上下方向の曲げモーメントが作用するが、該フロントサイドメンバ４のリヤメンバ４Ｂを多角形の一定の閉断面に押出成形してあるため曲げ剛性が高く、また、ダッシュパネル１は閉断面構造に車幅方向に押出し成形してフロントサイドメンバ４の軸方向入力に対する曲げ剛性を高めてあって、このフロントサイドメンバ４に作用する上下方向の曲げモーメントに対してダッシュパネル１の曲げ方向で強度的に有利に受けて該上下曲げモーメントを吸収することができ、従って、リヤメンバ４Ｂの折れ曲がりや、ダッシュパネル１との結合部分での折れ曲がりを生じることがなく、フロントメンバ４Ａを有効に潰れ変形させることができる。
【００６１】
左右のフロントメンバ４Ａの前端側はクロスメンバ２５を結合して連結してあるため、これらメンバ前端部間のスパンが拡大する際には図１２の仮想線で示すように連結メンバ２６がねじれ回転し、従って、フロントメンバ４Ａにねじりトルクが発生するが、このフロントメンバ４Ａは単位ねじり角に対して大きなねじりトルクを吸収でき、かつ、ねじりによる断面変形が生じにくい円形断面に形成してあるから、前述のように左右のフロントメンバ４Ａの端部間スパンが拡大する際にフロントメンバ４Ａにねじり力が作用しても、該フロントメンバ４Ａを局部的な壁面座屈による折れ曲がりを伴うことなく適正に潰れ変形させることができる。
【００６２】
本実施形態ではメンバ連結部材３の上壁３Ｂ₁の後側部には位置決め段部２１を形成してあって、この位置決め段部２１がフロントサイドメンバ４のリヤメンバ４Ｂの車幅方向内側の上縁に係合して、左右のフロントサイドメンバ４を所定の平面ハの字状の開き角度に適正に組付けることができるため、設計通りのフロントサイドメンバ４の潰れ特性を得ることができる。
【００６３】
また、このメンバ連結部材３の車幅方向内側の側壁１９（側壁３Ｂ₂）には、回動支点であるロケートピン１５付近で前記リヤメンバ４Ｂの車幅方向内側の側壁に当接する凹設部２２を前後方向に形成してあるから、該ロケートピン１５付近の断面係数を大きくできることに加えて、メンバ連結部材３の側壁１９の面剛性を高められるため、フロントサイドメンバ４の左右方向の支持剛性・強度を高めることができる。
【００６４】
一方、前記ロケートピン１５はサスペンションマウントボルト８の同軸心上に設けてあるため、該ロケートピン１５を中心とするフロントサイドメンバ４の回転支持に、サスペンションメンバ１０自体の剛性・強度を寄与させることができ、該ロケートピン１５の支持剛性を高めてフロントサイドメンバ４の回転を安定させることができる。
【００６５】
また、フロントサイドメンバ４はこのロケートピン１５の近傍でのみメンバ連結部材３に接合して、ロケートピン１５から後方の部分は該メンバ連結部材３と非接合状態としてあるため、前面衝突時にフロントサイドメンバ４を確実に回転作動させることができる。
【００６６】
更に、前記メンバ連結部材３は前端部にフロントサイドメンバ４のリヤメンバ４Ｂの下半部に嵌合する受容部７ａを形成したアーム部７を有するロア部材３Ａと、前端部にリヤメンバ４Ｂとの嵌合部１７を形成したアッパ部材３Ｂとの２部品で構成してあって、フロントサイドメンバ４の組付けに際しては、リヤメンバ４Ｂの後端部をロア部材３Ａのアーム部７の受容部７ａ上に嵌合，載置し、その上方もしくは側方からアッパ部材３Ｂを嵌合することによってメンバ連結部材３に容易に組付けることができて、ロボットによる自動組付けが可能となり、また、これらロア部材３Ａ，アッパ部材３Ｂとの嵌合によってフロントサイドメンバ４の位置決めと仮保持を行えるため、専用の車体組付治具設備が不要となり、大幅なコストダウンを実現することができる。
【００６７】
特に、前記ロア部材３Ａは鋳造成形してサスペンションマウントボルト８を鋳ぐるみ固定し、この鋳ぐるみ固定部分に前述のように回動支点としてのロケートピン１５を立設してあるため、これらサスペンションマウントボルト８およびロケートピン１５を位置決め治具等を用いて精度出しを行うことなく容易に設定することができることは勿論、前記フロントサイドメンバ４の組付時には、このロケートピン１５をリヤメンバ４Ｂの下壁に設けたロケート孔１６に挿入，係合することによってフロントサイドメンバ４の前後方向の位置決めを行え、従って、組付作業性をより一層向上することができる。
【００６８】
他方、フロントバンパー２９のバンパーステイ３０は、クロスメンバ２５の連結メンバ２６に設けたステイ連結部２８に、フロントサイドメンバ４のフロントメンバ４Ａと同軸線上に支持してあるため、衝突入力をフロントメンバ４Ａの中心軸に適正に作用させることができる。
【００６９】
また、このバンパーステイ３０は前記ステイ連結部２８に水平方向に回動可能に支持してあるから、車両の前面衝突時に左右のフロントサイドメンバ４の前端部間のスパンが拡大する際の連結メンバ２６のねじれ回転を規制することがなく、前記スパン拡大作用を適正に行わせることができる。
【００７０】
また、フロントバンパー２９を衝突方向に向けることができて、フロントサイドメンバ４の軸線方向に適正に衝突入力を作用させることができる。
【図面の簡単な説明】
【図１】本発明の一実施形態を示す斜視図。
【図２】本発明の一実施形態におけるダッシュパネルとメンバ連結部材のロア部材との関係を示す分解斜視図。
【図３】本発明の一実施形態におけるダッシュパネルとメンバ連結部材およびフロントサイドメンバの組付状態を示す斜視図。
【図４】図３の分解斜視図。
【図５】図３の側面図。
【図６】図３の平面図。
【図７】図５のＡ−Ａ線に沿う断面図。
【図８】図５のＢ−Ｂ線に沿う断面図。
【図９】図５のＣ−Ｃ線に沿う断面図。
【図１０】図９のＤ−Ｄ線に沿う断面図。
【図１１】フロントサイドメンバとクロスメンバおよびフロントバンパーとの関係を示す斜視図。
【図１２】クロスメンバ端部の連結メンバの変形作動を説明する正面図。
【符号の説明】
１ダッシュパネル
３メンバ連結部材
３Ａロア部材
３Ｂアッパ部材
３Ｂ₁ 上壁
３Ｂ₂ 側壁
４フロントサイドメンバ
４Ａフロントメンバ
４Ｂリヤメンバ
７アーム部
７ａ受容部
８サスペンションマウントボルト
１５回動支点（ロケートピン）
１６ロケート孔
１７アッパ部材の嵌合部
１９メンバ連結部材の側壁
１９ａ斜面部
２１位置決め段部
２２凹設部
２３ストッパ縁
２５クロスメンバ
２８ステイ連結部
２９フロントバンパー
３０バンパーステイ
Ｒ車室
Ｆ・Ｃフロントコンパートメント[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle body front structure of an automobile, and more particularly to a front side member arrangement structure that is arranged on both left and right sides of a front compartment to constitute a front-rear direction skeleton member of the vehicle body front.
[0002]
[Prior art]
On the lower side of the hood ridge panel that constitutes the left and right side walls of the front compartment, a front side member having a closed cross-sectional structure that constitutes the front-rear frame member of the front of the vehicle body is disposed, and the rear end of the front side member A dash panel that separates the passenger compartment and the front compartment is coupled to ensure the rigidity of the front portion of the vehicle body (see Japanese Patent Application Laid-Open No. 10-264862).
[0003]
[Problems to be solved by the invention]
The amount of collision energy absorption at the time of a frontal collision of the vehicle is almost proportional to the front-rear direction crushing stroke, and in order to expand the front-compartment crushing stroke, the front side member needs to be crushed and deformed in order from the front end side. is there.
[0004]
Thus, in order to cause the front side member to be crushed and deformed in order from the front end side, the bending rigidity and strength of the rear half of the front side member must be greater than those of the front half of the front side member. It is necessary to increase the rigidity of the connection between the front side member and the dash panel so that the crushing reaction force of the front side member can be maintained at a high level. It can end up.
[0005]
Therefore, the present invention can ensure the strength and rigidity of the rear half of the front side member, and can increase the crushing deformation stroke in the front-rear direction of the front compartment during a frontal collision of the vehicle, thereby increasing the amount of collision energy absorption. It is an object of the present invention to provide a front body structure for an automobile.
[0006]
[Means for Solving the Problems]
In the first aspect of the present invention, the front side member extending in the front-rear direction on the left and right sides of the front compartment separated from the front side of the vehicle compartment by the dash panel is provided, and the span between the left and right members is dash from the front end side. While it is arranged in the shape of a flat C that decreases as it reaches the panel side, it projects forward on the dash panel, and the closed cross-sectional area on the dash panel side with respect to the front end side To allow rotational movement of the rear end of the front side member inward in the vehicle width direction The enlarged member connecting member is coupled and disposed, and a rotation fulcrum is set at the front end portion thereof, and the rear end portion of the front side member is mounted on the member connecting member so as to be horizontally rotatable around the rotation fulcrum. In addition to holding and fixing, the dash panel is provided with a stopper edge that engages with the upper edge of the rear end of the front side member to restrain the upward movement of the rear end of the front side member and guides rotation in the horizontal direction. It is characterized by.
[0007]
In the second aspect of the invention, from the side wall in the vehicle width direction of the member connecting member according to claim 1 to the side wall in the vehicle width direction of the front side member from the vicinity of the rotation fulcrum to the dash panel side. It is characterized in that a slope part for restricting rotation is provided.
[0008]
According to a third aspect of the present invention, a positioning step is formed on the rear side portion of the upper wall of the member connecting member according to the first and second aspects to engage with the upper edge of the front side member in the vehicle width direction. It is characterized by that.
[0009]
According to a fourth aspect of the present invention, the rotation fulcrum according to any one of the first to third aspects is provided coaxially with the suspension mount bolt fixed to the member connecting member, and the front side member is located in the vicinity of the rotation fulcrum. It is characterized in that it is bonded and fixed to the member connecting member only at.
[0010]
In the fifth aspect of the invention, a recess is formed on the side wall in the vehicle width direction of the member connecting member according to any one of claims 1 to 4 so as to contact the side wall in the vehicle width direction of the front side member near the pivot point. It is characterized in that the portion is formed in the front-rear direction.
[0011]
According to a sixth aspect of the present invention, the member connecting member according to any one of the first to fifth aspects is provided with an arm portion that is coupled to the dash panel and projects forward, and a suspension mount bolt is fixed to the lower surface of the front end portion. A receiving portion that fits in a substantially lower half of the front side member at the front end portion of the arm portion, and a lower member provided with a pivot fulcrum,
The upper wall and the side wall in the vehicle width direction are formed in an inverted L-shaped cross section, the front end is a fitting part with the front side member, the rear end is joined to the dash panel and the side wall is joined to the lower member The upper member is composed of two parts.
[0012]
In the invention of claim 7, at least the lower member of the member connecting member according to claim 6 is cast-molded with a light metal material, and the suspension mount bolt is fixed by casting, and the suspension mount bolt is cast. It is characterized in that the fixed part is a rotation fulcrum.
[0013]
In the invention of claim 8, while the rotation fulcrum according to claims 1 to 7 is constituted by a locating pin protruding upward, a locating hole into which the locating pin is inserted and engaged is formed on the lower wall of the front side member. It is characterized by providing.
[0014]
In the invention of claim 9, the dash panel according to claims 1 to 8 is extruded with a lightweight metal material in a closed cross-sectional structure in the vehicle width direction, while at least the rear side portion of the front side member is made of a lightweight metal. It is characterized by being extruded into a constant closed cross-sectional shape with a material.
[0015]
According to a tenth aspect of the present invention, the front side member according to any one of the first to ninth aspects is composed of a front member and a rear member connected by a joint member. It is characterized in that the front end portions are connected by a cross member.
[0016]
The invention according to claim 11 is characterized in that a stay connecting portion for supporting the bumper stay of the front bumper on the same axis as the front member is provided at the connecting portion of the cross member according to claim 10 with the front member. Yes.
[0017]
The invention according to claim 12 is characterized in that the bumper stay according to claim 11 is connected to the stay connecting portion so as to be rotatable in the horizontal direction.
[0018]
【The invention's effect】
According to the first aspect of the present invention, the member connecting member in which the front side member is coupled to the dash panel has a closed cross-sectional area on the dash panel side larger than the front end side of the member connecting member. Since the rigidity of the connecting part with the panel is enhanced, and the left and right front side members are arranged in a flat square shape so that it can rotate horizontally around the rotation fulcrum, The front side member's crushing reaction force is kept high, the front half is crushed and deformed in order from the front end side, and the front side member is rotated around the pivot point in the direction of the square shape to collapse the front compartment. Can be increased.
[0019]
Therefore, after the front half of the front side member is completely crushed, the crushing deformation stroke of the front compartment can be continued and the crushing deformation stroke can be expanded, so that the amount of collision energy absorption can be significantly increased.
[0020]
In addition, when the front side member rotates, the upper edge of the rear end edge of the front side member is restrained by the stopper edge of the dash panel, and the rotation trajectory of the front side member is guided to guide the horizontal rotation. The rotation mode can be stabilized by limiting, and an increase in the crushing space of the front compartment can be realized extremely stably.
[0021]
According to the second aspect of the present invention, in addition to the effect of the first aspect of the invention, when the front side member rotates in the horizontal direction, the slope portion provided on the side wall in the vehicle width direction of the member connecting member. By restricting the rotation of the front side member, the C-shaped opening angle of the front side member can be maintained at the required angle, and therefore, the crushing reaction force characteristics due to the rotation of the front side member in the excessive opening direction Can be avoided.
[0022]
According to the third aspect of the present invention, in addition to the effects of the first and second aspects of the invention, the front side member has an upper edge on the inner side in the vehicle width direction at the rear end thereof, and the positioning step on the upper wall of the member connecting member. Can be appropriately assembled to a predetermined flat C-shaped opening angle, so that the collapse characteristic of the front side member as designed can be obtained.
[0023]
According to the fourth aspect of the present invention, in addition to the effects of the first to third aspects of the invention, since the rotation fulcrum is provided on the coaxial center of the suspension mount bolt, the front centered on the rotation fulcrum. The rigidity and strength of the suspension member itself can contribute to the rotation support of the side member, and the rotation rigidity of the front side member can be stabilized by increasing the support rigidity of the rotation fulcrum.
[0024]
In addition, the front side member is joined to the member connecting member only in the vicinity of the pivoting fulcrum, and the portion behind the pivoting fulcrum is not joined to the member connecting member. Can be rotated.
[0025]
According to the fifth aspect of the present invention, in addition to the effects of the first to fourth aspects of the invention, the side wall on the inner side in the vehicle width direction of the member connecting member is disposed on the inner side wall in the vehicle width direction of the front side member near the pivot point. In addition to being able to increase the section modulus in the vicinity of the pivot fulcrum by contacting the recessed portion provided on the side, the surface rigidity of the side wall of the member connecting member can be increased. Can be increased.
[0026]
According to the sixth aspect of the present invention, in addition to the effects of the first to fifth aspects, when the front side member is assembled, the rear end portion of the front side member is received by the lower member of the member connecting member. It can be easily assembled to the member connecting member by fitting and placing on the part and fitting the upper member from above or from the side, enabling automatic assembly by the robot. Since the front side member can be positioned and temporarily held by fitting with the lower member and the upper member, a dedicated vehicle body assembling jig facility is not required, and the cost can be significantly reduced.
[0027]
According to the seventh aspect of the present invention, in addition to the effect of the sixth aspect of the invention, the lower member of the member connecting member is cast and fixed, and the suspension mount bolt is fixed by casting. Since it is used as a fulcrum, the suspension mount bolt and the rotation fulcrum can be easily set using a positioning jig or the like without performing accuracy.
[0028]
According to the invention described in claim 8, in addition to the effects of the inventions of claims 1-7, the rotation fulcrum is constituted by a locate pin, and the lower wall of the front side member is provided with a locate hole. When the front side member is assembled, the front side member can be positioned in the front-rear direction by inserting and engaging the locating pin and the locating hole, so that the assembling workability can be further improved.
[0029]
According to the ninth aspect of the invention, in addition to the effects of the first to eighth aspects, at least the rear half of the front side member is extruded into a constant closed cross section, so that the bending rigidity is high. The bending direction of the dash panel, which is extruded in a direction perpendicular to the pushing direction of the front side member and has a high bending rigidity with respect to the vertical bending moment acting on the front side member at the time of a frontal collision of the vehicle, is strong. The vertical bending moment can be advantageously received and the front side member can be bent and the front half of the front side member can be properly deformed without bending at the connecting portion with the dash panel. Can be done.
[0030]
According to the invention of claim 10, in addition to the effects of the inventions of claims 1 to 9, the front member of the front side member can absorb a large torsion torque with respect to a unit torsion angle, and a cross section by torsion Since it is formed in a circular cross section that does not easily deform, when the front member between the left and right front side members expands during a frontal collision of the vehicle, the front member is localized even if a torsional force is applied to the front member. Therefore, it can be properly crushed and deformed without causing bending due to the wall buckling.
[0031]
According to the eleventh aspect of the invention, in addition to the effect of the tenth aspect of the invention, the bumper stay of the front bumper is supported on the coaxial line with the front member by the stay connecting portion. The shaft can be appropriately operated.
[0032]
According to the twelfth aspect of the invention, in addition to the effect of the eleventh aspect of the invention, since the bumper stay is pivotable in the horizontal direction at the stay connecting portion, the front end of the left and right front side members at the time of a frontal collision of the vehicle The span expansion action can be appropriately performed without restricting torsional rotation of the cross member side portion when the span between the portions is expanded.
[0033]
Further, the front bumper can be directed in the collision direction, and the collision input can be appropriately applied in the axial direction of the front side member.
[0034]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
[0035]
1 and 2, reference numeral 1 denotes a dash panel that separates a front compartment F / C in which a power unit such as an engine (not shown) is mounted in front of a passenger compartment R. The dash panel 1 is a lightweight metal material such as an aluminum alloy. Thus, a closed cross-sectional structure is extruded in the vehicle width direction.
[0036]
The left and right front side members 4 joined and arranged along the front-rear direction at the lower end of the hood ridge panel 2 (see FIGS. 7 to 9) separating the left and right sides of the front compartments F and C have a span between the left and right members. They are arranged in a plane C shape that decreases from the front end side to the dash panel 1 side, and their rear end portions are coupled to the dash panel 1 via member connecting members 3.
[0037]
The member connecting member 3 has an enlarged closed sectional area on the dash panel 1 side with respect to the front end side, and the member connecting member 3 is composed of two parts, a lower member 3A and an upper member 3B. Is also cast from a lightweight metal material similar to that described above.
[0038]
The lower member 3 </ b> A shares one base part 5 and is integrally formed on the left and right sides. The lower member 3 </ b> A is joined to the dash panel 1 at the front edge flange 5 a of the base part 5 and is formed on both left and right sides of the base part 5. The left and right end portions of the dash panel 1 are fitted and engaged with the positioning portion 6 thus joined.
[0039]
The lower member 3A is integrally formed with an arm portion 7 projecting forward of the dash panel 1, and the arm portion 7 and the upper member 3B form a closed cross section.
[0040]
A receiving portion 7a having a cross-sectional shape corresponding to the outer shape of the substantially lower half of the rear end portion of the front side member 4 is formed at the front end portion of the arm portion 7, and the rear portion of the front side member 4 is formed on the receiving portion 7a. The lower half of the end is fitted and placed.
[0041]
In addition, suspension mount bolts 8 and 9 projecting downward are cast-fixed to a portion slightly rearward of the receiving portion 7a of the arm portion 7 and the base portion 5, and the figure extends across these suspension mount bolts 8 and 9. As shown in FIG. 5, the suspension member 10 is fastened and fixed by nuts 8a and 9a, respectively.
[0042]
A locating pin 11 is formed on the coaxial core so as to protrude upward on the cast-hole fixing portion of the suspension mount bolt 9 on the rear side. 12 is inserted and engaged, and is fastened and fixed by a nut 14 on an inner wall via a retainer plate 13 to a screw portion 11a provided at the upper end thereof.
[0043]
As shown in FIGS. 3 to 5 and FIGS. 9 and 10, a locating pin 15 as a rotation fulcrum is formed on the coaxial core so as to protrude upward at the casting fixing portion of the suspension mount bolt 8 on the front side. Is inserted into and engaged with a locating hole 16 provided in the lower wall of the rear end portion of the front side member 4 so that the front side member 4 can be rotated in the horizontal direction around the locating pin 15 as a rotation center.
[0044]
The upper member 3B of the member connecting member 3 is the upper wall 3B. ₁ And side wall 3B on the inner side in the vehicle width direction ₂ The front end portion is formed as a fitting portion 17 that abuts and engages with the upper wall of the front side member 4 and the side wall in the vehicle width direction.
[0045]
The upper member 3B is joined and fixed to the dash panel 1 at the flange 18 formed at the rear edge, and the side wall 3B on the inner side in the vehicle width direction is fixed. ₂ A side wall 19 of the member connecting member 3 is formed by overlapping and joining the lower edge portion of the arm portion 7 to the upper edge portion of the side wall in the vehicle width direction, and the side wall 19 is constituted by the locate pin 15. A slope 19a for restricting rotation is formed so as to be separated from the side wall in the vehicle width direction of the front side member 4 from the vicinity of the rotation fulcrum to the dash panel 1 side.
[0046]
Upper wall 3B of upper member 3B ₁ A tongue piece 20 is extended on the side edge of the outer side in the vehicle width direction, and the tongue piece 20 is joined and fixed on the shelf of the closing plate 2a joined to the hood ridge panel 2 as shown in FIG. is there.
[0047]
This upper wall 3B ₁ A positioning step portion 21 that engages with the upper edge of the front side member 4 in the vehicle width direction is formed on the rear side portion.
[0048]
This positioning step 21 is provided on the upper wall 3B. ₁ However, it may be configured by a rib protrusion protruding downward.
[0049]
Further, the side wall 3B of the upper member 3B ₂ A concave portion 22 is formed in the front-rear direction in contact with the inner side wall in the vehicle width direction of the front side member 4 in the vicinity of the locating pin 15 that is the pivot point.
[0050]
The front side member 4 is engaged with the locating pin 15 and the locating hole 16 as described above, and is held by the member connecting member 3 so as to be rotatable in the horizontal direction with the rear end abutting against the dash panel 1. The front side member 4 is joined and fixed by welding to the member connecting member 3 only in the vicinity of the locating pin 15 which is the rotation fulcrum, and the member connecting member 3 is located between the rear of the rotation fulcrum 15 and the dash panel 1. And in a non-bonded state.
[0051]
On the other hand, on the front surface of the dash panel 1 is a stopper edge that engages with the upper edge of the rear end of the front side member 4 to restrict the upward movement of the rear end of the front side member 4 and guides horizontal rotation. 23 is formed in the extrusion direction.
[0052]
The front side member 4 is also extruded by a lightweight metal material such as an aluminum alloy into a certain closed cross-sectional shape. In this embodiment, the front side member 4 is divided into a front member 4A having a circular cross section and a rear member 4B having a polygonal cross section. The joint members 24 are connected to each other.
[0053]
The front end portions of the left and right front members 4A are coupled by a cross member 25 as shown in FIGS. 11 and 12, and this cross member 25 has connection members 26 connected and fixed to both end portions thereof. The front end of the front member 4A is fitted and fixed to a socket portion 27 provided on the member 26.
[0054]
A stay connecting portion 28 is provided on the front side of the socket portion 27 of the connecting member 26, and a rear end portion of a bumper stay 30 of a front bumper 29 (only a bumper armature is shown in FIGS. 1 and 11). Is inserted and supported on the same axis as the front member 4A, and is connected so as to be rotatable in the horizontal direction by a pin member (not shown).
[0055]
In FIG. 1, reference numeral 31 denotes a floor panel, and the floor panel 31 is also extruded in the front-rear direction to a closed cross-sectional structure using a light metal material similar to that described above.
[0056]
According to the structure of the above embodiment, the member connecting member 3 in which the front side member 4 is coupled to the dash panel 1 expands the closed sectional area on the dash panel 1 side relative to the front end side of the front side member 4. The rigidity of the engagement portion of the rear end portion with the dash panel 1 is enhanced, and the left and right front side members 4 are arranged in a plane C shape in the horizontal direction around the locating pin 15 that is a rotation fulcrum. Since it can be turned, the front side member 4 is maintained to have a high crushing reaction force at the time of a frontal collision of the vehicle, and the front half part is crushed and deformed in order from the front end side, and as shown by the phantom line in FIG. Can be rotated around the locating pin 15 in the direction in which the letter C opens, so that the space for crushing the front compartments F and C can be increased.
[0057]
Accordingly, after the front half of the front side member 4 is completely crushed, the crushing deformation stroke of the front compartments F and C can be continued and the crushing deformation stroke can be expanded, so that the amount of collision energy absorption can be significantly increased. .
[0058]
Moreover, when the front side member 4 is rotated, the stopper edge 23 of the dash panel 1 restrains the upward movement of the rear end edge of the front side member 4 and guides the rotation in the horizontal direction. The rotation mode can be stabilized by limiting the rotation trajectory of 4, and the increase in the crushing space of the front compartments F and C can be realized extremely stably.
[0059]
Here, during the rotation of the front side member 4, the rotation of the front side member 4 is restricted by the slope portion 19 a provided on the side wall 19 on the inner side in the vehicle width direction of the member connecting member 3. Since the opening angle of the letter-shaped shape can be maintained at a required angle, it is possible to avoid a decrease in the crushing reaction force characteristic due to the rotation of the front side member 4 in the excessive opening direction.
[0060]
A vertical bending moment acts on the front side member 4 at the time of a frontal collision of the vehicle. However, the rear member 4B of the front side member 4 is extruded into a fixed polygonal closed cross section so that the bending rigidity is high. The dash panel 1 is extruded in a closed cross-sectional structure in the vehicle width direction to increase the bending rigidity with respect to the axial input of the front side member 4, and against the vertical bending moment acting on the front side member 4. The bending moment of the dash panel 1 can be advantageously received to absorb the vertical bending moment, so that the rear member 4B is not bent or bent at the connecting portion with the dash panel 1, and the front panel is not bent. The member 4A can be effectively crushed and deformed.
[0061]
Since the front end sides of the left and right front members 4A are connected by connecting the cross members 25, when the span between the front end portions of these members expands, the connecting member 26 twists and rotates as shown by the phantom line in FIG. Accordingly, a torsional torque is generated in the front member 4A, but the front member 4A has a circular cross section that can absorb a large torsional torque with respect to a unit torsion angle and is less susceptible to a cross-sectional deformation due to torsion. As described above, even when a torsional force is applied to the front member 4A when the span between the end portions of the left and right front members 4A is expanded, the front member 4A is appropriate without bending due to local wall buckling. Can be crushed and deformed.
[0062]
In the present embodiment, the upper wall 3B of the member connecting member 3 ₁ A positioning step portion 21 is formed on the rear side portion, and the positioning step portion 21 engages with the upper edge in the vehicle width direction of the rear member 4B of the front side member 4 so that the left and right front side members 4 are engaged. Can be properly assembled to the opening angle of the predetermined flat C shape, so that the collapse characteristic of the front side member 4 as designed can be obtained.
[0063]
Further, the side wall 19 (the side wall 3B) on the inner side in the vehicle width direction of the member connecting member 3 ₂ ), The concave portion 22 is formed in the front-rear direction in contact with the inner side wall of the rear member 4B in the vicinity of the locating pin 15 that is a pivotal fulcrum, so that the section modulus in the vicinity of the locating pin 15 can be increased. In addition, since the surface rigidity of the side wall 19 of the member connecting member 3 can be increased, the support rigidity and strength of the front side member 4 in the left-right direction can be increased.
[0064]
On the other hand, since the locate pin 15 is provided on the coaxial center of the suspension mount bolt 8, the rigidity and strength of the suspension member 10 itself can contribute to the rotation support of the front side member 4 with the locate pin 15 as the center. Further, the rotation of the front side member 4 can be stabilized by increasing the support rigidity of the locate pin 15.
[0065]
Further, since the front side member 4 is joined to the member connecting member 3 only in the vicinity of the locate pin 15, and the rear part from the locate pin 15 is not joined to the member connecting member 3, the front side member 4 is in a front collision. Can be reliably rotated.
[0066]
Further, the member connecting member 3 is fitted with a lower member 3A having an arm portion 7 having a receiving portion 7a fitted to a lower half portion of the rear member 4B of the front side member 4 at a front end portion and a rear member 4B at a front end portion. The upper member 3B and the upper member 3B are formed with two parts. When the front side member 4 is assembled, the rear end portion of the rear member 4B is placed on the receiving portion 7a of the arm portion 7 of the lower member 3A. By fitting, placing, and fitting the upper member 3B from above or from the side, it can be easily assembled to the member connecting member 3, and can be automatically assembled by a robot. Since the front side member 4 can be positioned and temporarily held by fitting with the 3A and upper members 3B, a dedicated car body assembling jig facility is not required, and the cost is greatly reduced. It can be.
[0067]
In particular, the lower member 3A is cast and fixed to the suspension mount bolt 8 by casting, and the locating pin 15 as a rotation fulcrum is erected at the casting fixing portion as described above. 8 and the locating pin 15 can be easily set using a positioning jig or the like without increasing the accuracy. Of course, when the front side member 4 is assembled, the locating pin 15 is provided on the lower wall of the rear member 4B. By inserting and engaging with the locating hole 16, the front side member 4 can be positioned in the front-rear direction, and therefore the assembly workability can be further improved.
[0068]
On the other hand, the bumper stay 30 of the front bumper 29 is supported on the stay connecting portion 28 provided on the connecting member 26 of the cross member 25 on the same axis as the front member 4A of the front side member 4, so that the collision input is received from the front member 4A. It can be made to act appropriately on the central axis.
[0069]
Further, since the bumper stay 30 is supported by the stay connecting portion 28 so as to be rotatable in the horizontal direction, the connecting member when the span between the front end portions of the left and right front side members 4 is expanded in the event of a frontal collision of the vehicle. The torsional rotation action can be appropriately performed without restricting the torsional rotation of 26.
[0070]
Further, the front bumper 29 can be directed in the collision direction, and the collision input can be appropriately applied in the axial direction of the front side member 4.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of the present invention.
FIG. 2 is an exploded perspective view showing a relationship between a dash panel and a lower member of a member connecting member in an embodiment of the present invention.
FIG. 3 is a perspective view showing an assembled state of a dash panel, a member connecting member, and a front side member in an embodiment of the present invention.
4 is an exploded perspective view of FIG. 3. FIG.
5 is a side view of FIG. 3. FIG.
6 is a plan view of FIG. 3. FIG.
7 is a cross-sectional view taken along line AA in FIG.
8 is a cross-sectional view taken along line BB in FIG.
9 is a cross-sectional view taken along line CC in FIG.
10 is a cross-sectional view taken along the line DD of FIG.
FIG. 11 is a perspective view showing a relationship between a front side member, a cross member, and a front bumper.
FIG. 12 is a front view for explaining the deformation operation of the connecting member at the end of the cross member.
[Explanation of symbols]
1 Dash panel
3 Member connection members
3A Lower member
3B Upper member
3B ₁ Upper wall
3B ₂ Side wall
4 Front side members
4A Front member
4B Rear member
7 Arm
7a Receptor
8 Suspension mount bolt
15 Rotating fulcrum (Locate pin)
16 Locating hole
17 Upper member fitting part
19 Side wall of member connecting member
19a Slope
21 Positioning step
22 recessed part
23 Stopper edge
25 Cross member
28 Stay connection
29 Front bumper
30 Bumper stay
R compartment
FC front compartment

Claims

Front side members that extend in the front-rear direction on the left and right sides of the front compartment separated by the dash panel on the front side of the passenger compartment are flattened to reduce the span between the left and right members from the front end side to the dash panel side. While being arranged in a letter shape, the dash panel projects forward, and the closed cross-sectional area on the dash panel side with respect to the front end side can be allowed to rotate inward in the vehicle width direction at the rear end of the front side member. The member connecting member expanded to a position is connected and a rotation fulcrum is set at the front end of the member connecting member, and the rear end of the front side member can be horizontally rotated around the rotation fulcrum on the member connecting member. While holding and fixing, engaging the upper edge of the rear end of the front side member on the dash panel to restrain the upward movement of the rear end of the front side member, and Body front structure for an automobile, characterized in that a stopper edge for guiding the rotation of the horizontal direction.

It is characterized in that a slope part for restricting rotation is provided on the side wall in the vehicle width direction of the member connecting member so as to be separated from the side wall in the vehicle width direction of the front side member from the vicinity of the rotation fulcrum to the dash panel side. The vehicle body front part structure according to claim 1.

The vehicle body front of an automobile according to claim 1, wherein a positioning step portion that engages with the upper edge of the front side member in the vehicle width direction is formed on the rear side portion of the upper wall of the member connecting member. Part structure.

The rotation fulcrum is provided coaxially with a suspension mount bolt fixed to the member connection member, and the front side member is joined and fixed to the member connection member only in the vicinity of the rotation fulcrum. 4. The vehicle body front structure according to any one of 3 above.

5. A concave portion that is in contact with the inner side wall in the vehicle width direction of the front side member is formed in the front-rear direction on the inner side wall in the vehicle width direction of the member connecting member. The vehicle body front structure according to any one of the above.

The member connecting member is connected to the dash panel and protrudes forward, and has an arm portion with a suspension mount bolt fixedly attached to the lower surface of the front end portion, and is fitted to the front end portion of the front side member at the substantially lower half of the front side member. A receiving portion to be joined, a lower member provided with a pivot point,
The upper wall and the side wall in the vehicle width direction are formed in an inverted L-shaped cross section, the front end is a fitting part with the front side member, the rear end is joined to the dash panel and the side wall is joined to the lower member The vehicle body front part structure according to any one of claims 1 to 5, characterized in that the vehicle body front part structure is composed of two parts of the upper member.

7. The member connecting member is formed by casting at least a lower member of a lightweight metal material, and the suspension mount bolt is fixed by casting. The vehicle body front structure described in 1.

8. The rotary fulcrum is constituted by a locating pin protruding upward, and a locating hole into which the locating pin is inserted and engaged is provided in the lower wall of the front side member. Auto body front structure.

The dash panel is extruded with a lightweight metal material into a closed cross-sectional structure in the vehicle width direction, and at least the rear side portion of the front side member is extruded with a lightweight metal material into a constant closed cross-sectional shape. The vehicle body front part structure in any one of 1-8.

The front side member is composed of a front member and a rear member connected by a joint member, and at least the front member is formed in a circular cross section, and the front end portions of the left and right members are connected by a cross member. The vehicle body front part structure according to any one of 9.

The vehicle body front structure according to claim 10, wherein a stay connecting portion that supports a bumper stay of the front bumper on the same axis as the front member is provided at a joint portion of the cross member with the front member.

The vehicle body front part structure according to claim 11, wherein the bumper stay is connected to the stay connecting part so as to be rotatable in a horizontal direction.