JP3644395B2

JP3644395B2 - Automotive power unit layout

Info

Publication number: JP3644395B2
Application number: JP2001074740A
Authority: JP
Inventors: 学佐藤
Original assignee: Nissan Motor Co Ltd
Current assignee: Nissan Motor Co Ltd
Priority date: 2001-03-15
Filing date: 2001-03-15
Publication date: 2005-04-27
Anticipated expiration: 2021-03-15
Also published as: JP2002274194A

Description

【０００１】
【発明の属する技術分野】
本発明は自動車のパワーユニット配置構造に関する。
【０００２】
【従来の技術】
従来の自動車のパワーユニット配置構造の中には、例えば特開平１１−２４５６６８号公報に示されているように、車両の前面衝突時に伸長体を伸長作動させて車体前部をリフトアップさせると共に、ダッシュパネルの上部とパワーユニットとに跨って連結したリンク体の揺動によってパワーユニットをその下方の空きスペースへ落下させるようにしたものや、特開平７−１６４８９５号公報に示されているように、パワーユニットを予めダッシュパネルの下部の傾斜したトーボードの下側に傾斜して搭載し、車両の前面衝突時にはパワーユニットを該トーボードの傾斜に沿って落下させるようにしたもの等が知られている。
【０００３】
【発明が解決しようとする課題】
前記従来技術における前者の場合は、伸長体としての車高調整機構とその制御手段が必要となってコスト的に不利となってしまうことは否めず、また、後者の場合はパワーユニットを傾斜して搭載するため、この特殊なレイアウトに対応し得る車両仕様でない限り適用が不可能で、汎用性に欠ける不具合を生じる。
【０００４】
また、前記何れの構造にあっても、フロント搭載タイプのパワーユニット配置構造であるため、車室の後側に隔成した搭載室にパワーユニットを配置したリヤ搭載タイプの車両にそのまま適用することは難しい。
【０００５】
そこで、本発明は車両の後面衝突に対して、車室の後側に隔成されてパワーユニットを配置した搭載室の前後方向の潰れストロークを拡大できて、衝突エネルギー吸収効果を高めることができるリヤ搭載タイプの自動車のパワーユニット配置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、後傾した隔壁により車室の後側に隔成された搭載室にパワーユニットを取付ける構造であって、
前記搭載室の車幅方向両側部に車両の後面衝突に対して前方へ座屈変形可能なサイドメンバを設け、
パワーユニットの上部を前記サイドメンバに防振機能を有するマウント部材を介して前後方向に回転可能に支持すると共に、該マウント部材を車両の後面衝突時におけるサイドメンバとパワーユニットとの前後方向の相対移動に対して破断可能に構成し、
該パワーユニットの下部を、常態にあっては前記マウント部材を支点とするパワーユニットの前後方向回転を規制し、車両の後面衝突時に前記マウント部材の破断に先立ってパワーユニットに該マウント部材を支点とした後方への回転挙動を付与する回転制御手段で支持し、
この回転制御手段を、前端がサイドメンバの前部下側に支持された左右一対のラテラルメンバとこれらラテラルメンバの後端に跨って連結されてサイドメンバの後端下部に支持されたクロスメンバとを有するサスペンションメンバと、
前記クロスメンバとパワーユニットの下部とを連結するトルクロッドと、で構成し、
かつ、前記ラテラルメンバに、車両の後面衝突時に所定値以上の軸方向荷重が作用することによって該ラテラルメンバの前後方向中間部分の下方への屈曲を促す易屈曲部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に記載のマウント部材を、パワーユニットの車幅方向に延びる慣性主軸線上にほぼ揃えて配置したことを特徴としている。
【０００９】
請求項３の発明にあっては、請求項１，２に記載の易屈曲部を、ラテラルメンバの略直線状のメンバ一般部と、ラテラルメンバとクロスメンバとの連設部近傍で該ラテラルメンバのメンバ一般部の後端から斜め上方に向けて立上がって形成した傾斜部と、が連設する曲折部として形成したことを特徴としている。
【００１０】
請求項４の発明にあっては、請求項１〜３に記載の自動車のパワーユニット配置構造であって、トルクロッドとクロスメンバとを防振機能を有するマウント部材を介して連結したことを特徴としている。
【００１１】
請求項５の発明にあっては、請求項１〜４に記載の自動車のパワーユニット配置構造であって、サイドメンバは、前記隔壁に接合される前端側のメンバ基部の剛性を高くし、後端からパワーユニットを支持する中間部に亘る領域の剛性を低くしたことを特徴としている。
【００１２】
請求項６の発明にあっては、請求項１〜５に記載の自動車のパワーユニット配置構造であって、前記隔壁を軽量金属材料をもって車幅方向に閉断面に押出し成形した押出し材で構成したことを特徴としている。
【００１３】
【発明の効果】
請求項１に記載の発明によれば、車室と搭載室とを隔成する隔壁はシート配設のため後傾していて、該隔壁の上側部とパワーユニット上端との前後方向距離が狭まっているが、車両の後面衝突時には回転制御手段によってマウント部材の破断に先立ってパワーユニットにマウント部材を支点とした後方への回転挙動を付与する。
特に、この車両の後面衝突時には、回転制御手段におけるトルクロッドによってパワーユニットの下部を前方へ押動して、該パワーユニットに後方への回転挙動を直ちに付与できると共に、ラテラルメンバがその中間部分で易屈曲部を起点にして下向きにくの字状に折れ変形して、トルクロッドに下向きの回転モーメントを発生させるため、パワーユニットを強制的に下方へ引き落すことができる。
【００１４】
このパワーユニットの後方への回転挙動により前記隔壁上側部とパワーユニット上端との前後方向距離が拡大されて、後面衝突初期でパワーユニットの上端部分が隔壁に干渉するのが回避され、このパワーユニットの後方への回転挙動に続いてサイドメンバの前方への座屈変形に伴って前記マウント部材が破断して、該パワーユニットの搭載室下方の空きスペースへの落下を許容する。
【００１５】
この結果、搭載室の全長を拡大しなくてもその前後方向の潰れストロークを拡大でき、サイドメンバの前方への座屈変形を適正に行わせて衝突エネルギーを合理的に吸収することができると共に、サイドメンバの前方への座屈変形の進行によってパワーユニットが隔壁に干渉しても、該パワーユニットを隔壁のスロープに沿って下方へ移動させることができるため、前記隔壁の車室側への変形を抑制することができる。
【００１６】
また、通常時は前記マウント部材の防振機能によって、パワーユニット振動の車体側への伝播抑制効果を十分に確保することができる。
更に、サスペンションメンバを回転制御手段の構成部材として有効利用できるため、設計上およびコスト上有利に得ることができる。
【００１７】
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、マウント部材をパワーユニットの車幅方向に延びる慣性主軸線上にほぼ揃えて配置してあるため、パワーユニットの後方への回転挙動をスムーズに行わせることができる。
【００２０】
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、易屈曲部を構成する曲折部を、ラテラルメンバのクロスメンバとの連設部近傍に設定して、略直線状のメンバ一般部と傾斜部との長さ比率を大きくしてあるため、車両の後面衝突時にラテラルメンバが前記曲折部を起点に下向きにくの字状に折れ変形した場合に、クロスメンバをほぼ回転中心とする傾斜部の下向きの回転角が大きく、これに伴ってトルクロッドによるパワーユニットの引き下げ力を大きくすることができる。
【００２１】
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、トルクロッドとクロスメンバとの連結部分に介装したマウント部材の防振機能によって、パワーユニット振動の車体側への伝播抑制を徹底することができる。
【００２２】
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、隔壁に接合したサイドメンバ前端側のメンバ基部の剛性を高くしてあるため、車両の後面衝突時における該サイドメンバの軸圧壊反力を高められると共に、後端から中間部に亘る領域の剛性を低くしてあるため、サイドメンバを後端から前方へ向けて整然と座屈変形させることができて、衝突エネルギー吸収効果を高めることができる。
【００２３】
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、隔壁の剛性が高められるため、パワーユニットの落下時における該隔壁のスロープに沿う下方移動をスムーズに行わせることができて、隔壁の車室側への変形抑制効果を高めることができる。
【００２４】
【発明の実施の形態】
以下、本発明の実施形態を図面と共に詳述する。
【００２５】
図１〜３において、１はフロントフロア、２は前端をフロントフロア１の後端に突合わせて接合した車室後部の隔壁としてのシートクロスメンバで、該シートクロスメンバ２によって車室３の後側に搭載室としてのエンジンルーム４を隔成している。
【００２６】
このシートクロスメンバ２は図外のリヤシートの配設のため後傾して形成してあり、その略下半部は後述するサイドメンバのキックアップ部の傾斜角度に合わせて傾斜角度を小さくし、略上半部は該下半部の上端から立上がらせて傾斜角度を大きくしてあり、該シートクロスメンバ２の上端を略水平なリヤパーセルシェルフ５に接合してある。
【００２７】
本実施形態ではフロントフロア１をアルミ合金等の軽量金属材料をもって車体前後方向に閉断面に押出し成形した押出し材で構成してあると共に、シートクロスメンバ２もフロントフロア１と同様の軽量金属材料をもって車幅方向に押出し成形した押出し材で構成してある。
【００２８】
エンジンルーム４の車幅方向両側部には、車体前後方向に延在する車体後部の前後方向骨格部材であるリヤサイドメンバ（サイドメンバ）６を配設してある。
【００２９】
このリヤサイドメンバ６の前端側のメンバ基部としての傾斜成形したキックアップ部６Ａは、前記シートクロスメンバ２の略下半部の後面に突き合わせて接合してあると共に、前端をフロントフロア１の後端部下面に廻り込んで接合してある。
【００３０】
リヤサイドメンバ６は車両の後面衝突時におけるエネルギー吸収の主要部材を成すもので、該リヤサイドメンバ６は一般のものと同様に後面衝突時に作用する軸圧潰荷重によって前後方向に座屈変形可能に構成され、例えばパネル材を組合わせた閉断面構造、あるいはアルミ合金の押出し成形による閉断面構造とされ、必要に応じて前後方向の蛇腹状の座屈変形を誘起させる易圧潰部が設けられる。
【００３１】
７はエンジンルーム４内に搭載したパワーユニットとしてのエンジンユニットを示し、エンジン本体７Ａとトランスミッション７Ｂとを備えていて、エンジンルーム４に横置きに搭載してある。
【００３２】
エンジンユニット７は前記左右のリヤサイドメンバ６，６上にマウント部材８，８を介して防振支持してある。
【００３３】
このマウント部材８は例えばブロック状のインシュレータラバー８ａを防振材として備えていて、エンジンユニット７の両側端に突設した支軸７ａを該インシュレータラバー８ａで弾性支持して、該インシュレータラバー８ａにより防振機能を発揮すると共に、車両の後面衝突時におけるリヤサイドメンバ６とエンジンユニット７との前後方向の相対移動に対しては、該インシュレータラバー８ａが破断してエンジンユニット７とリヤサイドメンバ６との支持連結形態が解除可能に構成される。
【００３４】
本実施形態では前記マウント部材８，８をエンジンユニット７の車幅方向に延びる慣性主軸線Ｏ上にほぼ揃えて配置してある。
【００３５】
また、リヤサイドメンバ６は前記メンバ基部であるキックアップ部６Ａの閉断面積を大きくし、エンジンユニット７を防振支持した中間部から後端に亘る領域Ｓ_L部分はその閉断面積を小さくして、前記キックアップ部６Ａの剛性を高くし、前記領域Ｓ_L部分の剛性を該キックアップ部６Ａよりも低く設定してある。
【００３６】
ここで、前記エンジンルーム４の下側部にはエンジンユニット７の下部を支持して、常態にあっては前記マウント部材８，８を支点とするエンジンユニット７の前後方向回転を規制し、車両の後面衝突時に前記マウント部材８，８の破断に先立ってエンジンユニット７に該マウント部材８，８を支点とした後方への回転挙動を付与する回転制御手段９を配設してある。
【００３７】
本実施形態にあってはこの回転制御手段９を、前記リヤサイドメンバ６，６よりも下方に配設されて図外のリヤサスペンションリンクを支持するサスペンションメンバ１１と、該サスペンションメンバ１１とエンジンユニット７の下部とに連結したトルクロッド１２とで構成している。
【００３８】
サスペンションメンバ１１は、前端がリヤサイドメンバ６のキック部６Ａの下面に有段成形した前側座部１３に連結支持された左右一対のラテラルメンバ１５と、これらラテラルメンバ１５の後端に跨って連結されて、リヤサイドメンバ６の後端下面に突設した後側座部１４の下面に連結支持されたクロスメンバ１６を備えている。
【００３９】
ラテラルメンバ１５はその前後端部を斜め上向きに曲折成形して中間部分を一段低く形成してあり、これら前後の曲折部１７Ｆ，１７Ｒを易屈曲部として、車両の後面衝突時にラテラルメンバ１５に所定値以上の軸方向荷重が作用することにより、これら易屈曲部１７Ｆ，１７Ｒを起点に下向きに屈曲して、中間部分の略中央を頂点とするくの字状の折れ変形を促すようにしてある。
【００４０】
一方、トルクロッド１２はクロスメンバ１６の車幅方向中央部と、エンジンユニット７のトランスミッション７Ｂの後方に張り出した部分（出力軸ハウジング）の下面とに跨って連結してある。
【００４１】
また、本実施形態ではこのトルクロッド１２とクロスメンバ１６との連結部分に、インシュレータラバー１８ａを有するマウント部材１８を介装して、エンジンユニット７の下部を該マウント部材１８によってサスペンションメンバ１１に防振支持するようにしてある。
【００４２】
図３〜５中、１０はフロア両サイドの前後方向骨格部材であるサイドシルを示す。
【００４３】
以上の実施形態の構造によれば、車室３とエンジンルーム４とを隔成するシートクロスメンバ２はリヤシート配設のため後傾していて、該シートクロスメンバ２の上側部とエンジンユニット７の上端との前後方向距離Ｓ₁が挟まっているが、車両の後面衝突時には回転制御手段９によってリヤサイドメンバ６上のマウント部材８の破断に先立ってエンジンユニット７に該マウント部材８を支点とした後方への回転挙動を付与する。
【００４４】
これは具体的には、図４に示すように後面衝突入力がリヤサイドメンバ６の後端に作用すると、該リヤサイドメンバ６が前方に向けて座屈変形を開始すると同時に、サスペンションメンバ１１にも後面衝突入力が作用してラテラルメンバ１５を折れ変形させ、トルクロッド１２によってエンジンユニット７の下部を前方へ押動して、該エンジンユニット７に直ちに後方への回転挙動を付与する。
【００４５】
このエンジンユニット７の後方への回転挙動により前記シートクロスメンバ２の上側部とエンジンユニット７の上端との前後方向距離がＳ₁からＳ₂へと拡大されて、後面衝突初期でエンジンユニット７の上端部分がシートクロスメンバ２に干渉するのが回避される。
【００４６】
他方、前記エンジンユニット７は慣性力によってリヤサイドメンバ６と前後方向に相対移動し、マウント部材８に所定値以上の負荷が作用すると該マウント部材８が破断し、エンジンユニット７の連結支持状態を解除してエンジンルーム下方への落下を許容することと併せて、サスペンションメンバ１１のラテラルメンバ１５の中間部分が下向きにくの字状に折れ変形して、クロスメンバ１６を介してトルクロッド１２に下向きの回転モーメントを発生させ、エンジンユニット７を強制的に下方へ引き落す作用が生じることによって、前記エンジンユニット７をエンジンルーム４の下方の空きスペースへ落下させる。
【００４７】
この結果、エンジンルーム４の全長を拡大しなくてもその前後方向の潰れストロークを拡大でき、リヤサイドメンバ６の前方への座屈変形を適正に行わせて衝突エネルギーを合理的に吸収することができると共に、図５に示すようにリヤサイドメンバ６の前方への座屈変形の進行によってエンジンユニット７がシートクロスメンバ２に干渉しても、該エンジンユニット７をシートクロスメンバ２のスロープに沿って下方へ移動させることができるため、前記シートクロスメンバ２の車室３側への変形を抑制することができる。
【００４８】
ここで、特に本実施形態にあっては前記マウント部材８，８を、エンジンユニット７の車幅方向に延びる慣性主軸線０上にほぼ揃えて配置してあるため、エンジンユニット７の後方への回転挙動をスムーズに行わせることができる。
【００４９】
また、リヤサイドメンバ６はシートクロスメンバ２に接合したサイドメンバ前端側のメンバ基部６Ａの剛性を高くしてあるため、車両の後面衝突時における該リヤサイドメンバ６の軸圧壊反力を高められると共に、後端から中間部に亘る領域Ｓ_Lの剛性を低くしてあるため、リヤサイドメンバ６を後端から前方へ向けて整然と座屈変形させることができて、衝突エネルギー吸収効果を高めることができる。
【００５０】
更に、前述のようにサスペンションメンバ１１を回転制御手段９の構成部材として有効利用しているため、設計上およびコスト上有利に得ることができると共に、トルクロッド１２とサスペンションメンバ１１のクロスメンバ１６との連結部分にマウント部材１８を介装して、該エンジンユニット７の下部をサスペンションメンバ１１に防振支持しているので、リヤサイドメンバ６上に配置したマウント部材８の防振機能と相俟って、通常時におけるエンジンユニット振動の車体側への伝播抑制を徹底することができる。
【００５１】
一方、シートクロスメンバ２は軽量金属材料の押出し材で構成しているため、シートクロスメンバ２の剛性が高く、エンジンユニット７の落下時における該シートクロスメンバ２のスロープに沿う下方移動をスムーズに行わせることができて、シートクロスメンバ２の車室側への変形抑制効果を高めることができる。
【００５２】
図６はサスペンションメンバ１１の異なる例を示すもので、ラテラルメンバ１５を略直線状のメンバ一般部１５Ａと、ラテラルメンバ１５とクロスメンバ１６との連設部近傍で前記メンバ一般部１５Ａの後端から斜め上方に向けて立上がって形成した傾斜部１５Ｂとで構成し、これらメンバ一般部１５Ａと傾斜部１５Ｂとで形成された曲折部１７Ｒ・Ｒを易屈曲部としてある。
【００５３】
このように易屈曲部を構成する曲折部１７Ｒ・Ｒを、ラテラルメンバ１５とクロスメンバ１６との連設部近傍に設定して、略直線状のメンバ一般部１５Ａと傾斜部１５Ｂとの長さＬ₁，Ｌ₂の比率を大きくすることによって、車両の後面衝突時にラテラルメンバ１５が前記曲折部１７Ｒ・Ｒを起点に下向きにくの字状に折れ変形した場合に、クロスメンバ１６をほぼ回転中心とする傾斜部１５Ｂの下向きの回転角θが大きく、これに伴ってトルクロッド１２によるエンジンユニット７の引き下げ力を大きくすることができる。
【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を示す平面図。
【図３】本発明の一実施形態を模式的に示す側面図。
【図４】本発明の一実施形態の後面衝突初期における変形状態を模式的に示す側面図。
【図５】本発明の一実施形態の後面衝突後期における変形状態を模式的に示す側面図。
【図６】サスペンションメンバの異なる例を示す略示的側面説明図。
【符号の説明】
２シートクロスメンバ（隔壁）
３車室
４エンジンルーム（搭載室）
６リヤサイドメンバ（サイドメンバ）
６Ａキックアップ部（メンバ基部）
７エンジンユニット（パワーユニット）
８パワーユニット上部のマウント部材
９回転制御手段
１１サスペンションメンバ
１２トルクロッド
１５ラテラルメンバ
１５Ａメンバ一般部
１５Ｂ傾斜部
１６クロスメンバ
１７Ｆ，１７Ｒ，１７Ｒ・Ｒ易屈曲部
１８パワーユニット下部のマウント部材
０慣性主軸線
Ｓ_Lサイドメンバの中間部から後端の領域
θ 傾斜部の回転角[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power unit arrangement structure for an automobile.
[0002]
[Prior art]
In a conventional automobile power unit arrangement structure, as shown in, for example, Japanese Patent Application Laid-Open No. 11-245668, when the frontal collision of the vehicle, the extension body is extended to lift up the front part of the vehicle body, and the dash A power unit that is dropped into an empty space below it by swinging a link body that is connected across the upper part of the panel and the power unit, or as disclosed in JP-A-7-164895 There are known devices that are mounted in an inclined manner on the lower side of an inclined toe board at the lower part of the dash panel, and the power unit is dropped along the inclination of the toe board at the time of a frontal collision of the vehicle.
[0003]
[Problems to be solved by the invention]
In the case of the former in the prior art, a vehicle height adjustment mechanism as an extension body and its control means are necessary, and it cannot be denied that the cost is disadvantageous. In the latter case, the power unit is inclined. Since it is mounted, it is impossible to apply unless the vehicle specification is compatible with this special layout, resulting in a problem that lacks versatility.
[0004]
In addition, in any of the above structures, since it is a front-mounted type power unit arrangement structure, it is difficult to apply as it is to a rear-mounted type vehicle in which the power unit is arranged in a mounting room separated on the rear side of the vehicle compartment. .
[0005]
Accordingly, the present invention can increase the collision energy absorption effect by expanding the crushing stroke in the front-rear direction of the mounting chamber that is separated on the rear side of the vehicle compartment and arranged with the power unit against the rear collision of the vehicle. It provides a power unit arrangement structure for an on-board type automobile.
[0006]
[Means for Solving the Problems]
In the invention of claim 1, the power unit is attached to a mounting chamber separated on the rear side of the passenger compartment by a rearwardly inclined partition wall,
Provide side members that can buckle forward with respect to a rear collision of the vehicle on both sides in the vehicle width direction of the mounting chamber,
The upper part of the power unit is supported on the side member so as to be rotatable in the front-rear direction via a mount member having a vibration isolating function, and the mount member is used for relative movement in the front-rear direction between the side member and the power unit at the time of a rear-end collision of the vehicle. It is configured so that it can be broken,
The lower part of the power unit is normally controlled to prevent the power unit from rotating in the front-rear direction with the mount member as a fulcrum, and to the power unit at the rear with the mount member as a fulcrum prior to the breakage of the mount member in the event of a rear-end collision of the vehicle supported by rotation control means for imparting rotational behavior to,
This rotation control means includes a pair of left and right lateral members whose front ends are supported on the lower side of the front part of the side members, and a cross member that is connected across the rear ends of these lateral members and supported at the lower rear end of the side members. A suspension member having,
A torque rod connecting the cross member and the lower part of the power unit;
In addition, the lateral member is provided with an easy-bending portion that facilitates downward bending of the intermediate portion in the front-rear direction of the lateral member when an axial load of a predetermined value or more acts upon a rear-end collision of the vehicle. .
[0007]
The invention according to claim 2 is characterized in that the mount member according to claim 1 is arranged substantially on the inertia main axis extending in the vehicle width direction of the power unit.
[0009]
According to a third aspect of the present invention, the easily bent portion according to any one of the first and second aspects is arranged in the vicinity of the generally straight member general portion of the lateral member and the connecting portion between the lateral member and the cross member. It is characterized in that it is formed as a bent portion that is connected to an inclined portion that is formed to rise obliquely upward from the rear end of the member general portion.
[0010]
According to a fourth aspect of the present invention, there is provided a power unit arrangement structure for an automobile according to any one of the first to third aspects, wherein the torque rod and the cross member are connected via a mount member having a vibration isolating function. Yes.
[0011]
According to a fifth aspect of the present invention, there is provided a power unit arrangement structure for an automobile according to the first to fourth aspects, wherein the side member increases the rigidity of the member base portion on the front end side joined to the partition wall, and the rear end. The rigidity of the region extending from the intermediate portion supporting the power unit to the intermediate portion is reduced.
[0012]
In invention of Claim 6 , it is the power unit arrangement structure of the motor vehicle of Claims 1-5 , Comprising: The said partition was comprised with the extrusion material extruded by the closed cross section in the vehicle width direction with the lightweight metal material. It is characterized by.
[0013]
【The invention's effect】
According to the first aspect of the present invention, the partition wall that separates the passenger compartment and the mounting chamber is inclined rearward due to the seat arrangement, and the longitudinal distance between the upper portion of the partition wall and the upper end of the power unit is reduced. However, at the time of a rear collision of the vehicle, the rotation control means gives the power unit a backward rotation behavior with the mount member as a fulcrum before the mount member is broken.
In particular, at the time of a rear collision of this vehicle, the lower part of the power unit can be pushed forward by a torque rod in the rotation control means, so that the power unit can be immediately imparted with a rearward rotation behavior, and the lateral member is easily bent at the middle part. The power unit can be forcibly pulled down because the torque rod generates a downward rotational moment by being bent and deformed downwardly starting from the portion.
[0014]
The distance between the upper part of the bulkhead and the upper end of the power unit is increased by the backward rotation behavior of the power unit, and the upper end of the power unit is prevented from interfering with the bulkhead at the beginning of the rear collision. Following the rotational behavior, the mount member breaks with the buckling deformation of the side member forward, allowing the power unit to drop into an empty space below the mounting chamber.
[0015]
As a result, the crushing stroke in the front-rear direction can be expanded without enlarging the entire length of the mounting chamber, and the collision energy can be rationally absorbed by appropriately performing the buckling deformation forward of the side member. Even if the power unit interferes with the bulkhead due to the forward buckling deformation of the side member, the power unit can be moved downward along the slope of the bulkhead. Can be suppressed.
[0016]
Further, at the normal time, the effect of suppressing the propagation of the power unit vibration to the vehicle body side can be sufficiently ensured by the anti-vibration function of the mount member.
Furthermore, since the suspension member can be effectively used as a constituent member of the rotation control means, it can be advantageously obtained in terms of design and cost.
[0017]
According to the second aspect of the present invention, in addition to the effect of the first aspect of the invention, the mount member is arranged substantially on the inertia main axis extending in the vehicle width direction of the power unit. The rotation behavior can be performed smoothly.
[0020]
According to the invention of claim 3 , in addition to the effects of the inventions of claims 1 and 2 , the bent portion constituting the easy-bend portion is set in the vicinity of the continuous portion with the cross member of the lateral member, Since the length ratio of the generally straight member general part and the inclined part is increased, when a lateral member bends and deforms downward in the shape of a circle starting from the bent part at the time of a rear collision of the vehicle, The downward rotation angle of the inclined portion with the member as the center of rotation is large, and accordingly, the pulling force of the power unit by the torque rod can be increased.
[0021]
According to the fourth aspect of the present invention, in addition to the effects of the first to third aspects, the vibration isolation function of the mount member interposed in the connecting portion between the torque rod and the cross member allows the power unit vibration to be It is possible to thoroughly suppress propagation to
[0022]
According to the fifth aspect of the invention, in addition to the effects of the first to fourth aspects of the invention, the rigidity of the member base portion on the side member front end side joined to the partition wall is increased. While the axial crushing reaction force of the side member can be increased and the rigidity of the region extending from the rear end to the intermediate portion is lowered, the side member can be buckled and deformed orderly from the rear end to the front, The impact energy absorption effect can be enhanced.
[0023]
According to the sixth aspect of the invention, in addition to the effects of the first to fifth aspects of the invention, the rigidity of the partition is increased, so that the downward movement along the slope of the partition is smoothly performed when the power unit is dropped. Therefore, the effect of suppressing deformation of the partition wall toward the passenger compartment can be enhanced.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0025]
1 to 3, 1 is a front floor, 2 is a seat cross member as a partition wall at the rear of the passenger compartment, the front end of which is abutted against the rear end of the front floor 1, and the rear of the passenger compartment 3 by the seat cross member 2. An engine room 4 as a mounting room is separated on the side.
[0026]
The seat cross member 2 is formed to be inclined rearward for the arrangement of a rear seat (not shown), and the lower half of the seat cross member 2 has an inclination angle reduced in accordance with an inclination angle of a kick-up portion of a side member to be described later. The substantially upper half is raised from the upper end of the lower half to increase the inclination angle, and the upper end of the seat cross member 2 is joined to a substantially horizontal rear parcel shelf 5.
[0027]
In the present embodiment, the front floor 1 is made of an extruded material that is extruded in a closed cross section in the vehicle longitudinal direction with a lightweight metal material such as an aluminum alloy, and the seat cross member 2 also has the same lightweight metal material as the front floor 1. It is composed of an extruded material extruded in the vehicle width direction.
[0028]
On both sides of the engine room 4 in the vehicle width direction, rear side members (side members) 6 which are front and rear direction skeleton members of the rear part of the vehicle body extending in the vehicle body front and rear direction are disposed.
[0029]
An inclined molded kick-up portion 6A as a member base portion on the front end side of the rear side member 6 is abutted against and joined to the rear surface of the substantially lower half portion of the seat cross member 2, and the front end is connected to the rear end of the front floor 1. It is wrapped around and joined to the lower surface of the part.
[0030]
The rear side member 6 constitutes a main member for energy absorption at the time of a rear collision of the vehicle, and the rear side member 6 is configured to be buckled and deformed in the front-rear direction by an axial crushing load acting at the time of the rear collision, in the same manner as a general member. For example, a closed cross-section structure in which panel materials are combined or a closed cross-section structure by extrusion molding of an aluminum alloy is provided, and an easy crushing portion that induces a bellows-like buckling deformation in the front-rear direction is provided as necessary.
[0031]
Reference numeral 7 denotes an engine unit as a power unit mounted in the engine room 4. The engine unit 7 includes an engine body 7 </ b> A and a transmission 7 </ b> B, and is mounted horizontally in the engine room 4.
[0032]
The engine unit 7 is supported on the left and right rear side members 6 and 6 by vibration-proofing via mount members 8 and 8.
[0033]
The mount member 8 includes, for example, a block-like insulator rubber 8a as a vibration isolating material, and support shafts 7a projecting from both ends of the engine unit 7 are elastically supported by the insulator rubber 8a. In addition to exhibiting a vibration isolating function, the insulator rubber 8a is broken and the engine unit 7 and the rear side member 6 are moved against the relative movement in the front-rear direction between the rear side member 6 and the engine unit 7 at the time of a rear-end collision of the vehicle. The support connection form is configured to be releasable.
[0034]
In the present embodiment, the mount members 8 are arranged substantially on the inertia main axis O extending in the vehicle width direction of the engine unit 7.
[0035]
Further, the rear side member 6 increases the closed cross-sectional area of the kick-up part 6A, which is the member base, and the area S _L extending from the intermediate part where the engine unit 7 is supported for vibration isolation to the rear end has a reduced closed cross-sectional area. Thus, the rigidity of the kick-up portion 6A is increased, and the rigidity of the region S _L is set lower than that of the kick-up portion 6A.
[0036]
Here, the lower part of the engine room 4 supports the lower part of the engine unit 7, and in the normal state, the rotation of the engine unit 7 with the mount members 8 and 8 as a fulcrum is restricted. Prior to the breakage of the mount members 8 and 8 at the time of rear-end collision, a rotation control means 9 is provided that gives the engine unit 7 a backward rotation behavior with the mount members 8 and 8 as fulcrums.
[0037]
In this embodiment, the rotation control means 9 is provided with a suspension member 11 disposed below the rear side members 6 and 6 to support a rear suspension link (not shown), the suspension member 11 and the engine unit 7. And a torque rod 12 connected to the lower part of the motor.
[0038]
The suspension member 11 has a front end connected to a pair of left and right lateral members 15 connected and supported by a front seat portion 13 formed stepwise on the lower surface of the kick portion 6A of the rear side member 6 and a rear end of these lateral members 15. The rear side member 6 includes a cross member 16 that is connected to and supported by the lower surface of the rear seat portion 14 that projects from the lower surface of the rear end of the rear side member 6.
[0039]
The lateral member 15 has its front and rear end portions bent obliquely upward to form an intermediate portion that is one step lower. The front and rear bent portions 17F and 17R are used as easy-bending portions, and the lateral member 15 has a predetermined shape applied to the lateral member 15 at the time of a vehicle rear surface collision. When an axial load greater than the value is applied, the bent portions 17F and 17R are bent downward from the starting point to promote a dogleg-shaped bending deformation with the approximate center of the intermediate portion as a vertex. .
[0040]
On the other hand, the torque rod 12 is connected across the center in the vehicle width direction of the cross member 16 and the lower surface of the portion (output shaft housing) projecting rearward of the transmission 7B of the engine unit 7.
[0041]
In the present embodiment, a mount member 18 having an insulator rubber 18 a is interposed at the connecting portion between the torque rod 12 and the cross member 16, and the lower portion of the engine unit 7 is prevented from being attached to the suspension member 11 by the mount member 18. I support it.
[0042]
3-5, 10 shows the side sill which is the front-back direction frame | skeleton member of both floor sides.
[0043]
According to the structure of the above embodiment, the seat cross member 2 that separates the vehicle compartment 3 and the engine room 4 is inclined rearward for the rear seat arrangement, and the upper portion of the seat cross member 2 and the engine unit 7 are arranged. A front-rear direction distance S ₁ with the upper end of the vehicle is sandwiched, but at the time of rear-end collision of the vehicle, the rotation control means 9 uses the mount member 8 as a fulcrum for the engine unit 7 prior to the break of the mount member 8 on the rear side member 6. Gives backward rotation behavior.
[0044]
Specifically, as shown in FIG. 4, when a rear collision input acts on the rear end of the rear side member 6, the rear side member 6 starts buckling deformation toward the front, and at the same time, the suspension member 11 also has a rear surface. The collision input acts to bend and deform the lateral member 15 and push the lower part of the engine unit 7 forward by the torque rod 12 to immediately give the engine unit 7 a rotational behavior to the rear.
[0045]
Due to the backward rotation behavior of the engine unit 7, the distance in the front-rear direction between the upper portion of the seat cross member 2 and the upper end of the engine unit 7 is increased from S ₁ to S ₂ . Interference of the upper end portion with the seat cross member 2 is avoided.
[0046]
On the other hand, the engine unit 7 is moved relative to the rear side member 6 in the front-rear direction by an inertial force, and when a load of a predetermined value or more is applied to the mount member 8, the mount member 8 is broken and the connection support state of the engine unit 7 is released. In addition to allowing the engine member to fall downward, the intermediate portion of the lateral member 15 of the suspension member 11 bends and deforms downward in a U-shape, and then downwards toward the torque rod 12 via the cross member 16. The engine unit 7 is dropped into an empty space below the engine room 4 by generating the rotational moment and forcibly pulling the engine unit 7 downward.
[0047]
As a result, the crushing stroke in the front-rear direction can be expanded without enlarging the overall length of the engine room 4, and the rear side member 6 can be buckled forward and the collision energy can be absorbed reasonably. As shown in FIG. 5, even if the engine unit 7 interferes with the seat cross member 2 due to the forward buckling deformation of the rear side member 6, the engine unit 7 is moved along the slope of the seat cross member 2. Since the seat cross member 2 can be moved downward, deformation of the seat cross member 2 toward the passenger compartment 3 can be suppressed.
[0048]
Here, particularly in the present embodiment, the mount members 8, 8 are substantially aligned on the inertia main axis 0 extending in the vehicle width direction of the engine unit 7, so The rotation behavior can be performed smoothly.
[0049]
In addition, since the rear side member 6 has the rigidity of the member base portion 6A on the front end side of the side member joined to the seat cross member 2, it is possible to increase the axial crushing reaction force of the rear side member 6 at the time of a rear surface collision of the vehicle. Since the rigidity of the region S _L extending from the rear end to the intermediate portion is lowered, the rear side member 6 can be buckled and deformed orderly from the rear end to the front, and the impact energy absorption effect can be enhanced.
[0050]
Further, since the suspension member 11 is effectively used as a component of the rotation control means 9 as described above, the suspension member 11 can be advantageously obtained in terms of design and cost, and the torque rod 12 and the cross member 16 of the suspension member 11 can be obtained. Since the lower part of the engine unit 7 is supported by the suspension member 11 in an anti-vibration manner with a mount member 18 interposed therebetween, in combination with the anti-vibration function of the mount member 8 disposed on the rear side member 6. Therefore, it is possible to thoroughly suppress propagation of engine unit vibration to the vehicle body side during normal times.
[0051]
On the other hand, since the seat cross member 2 is made of an extruded material of a lightweight metal material, the seat cross member 2 has high rigidity and smoothly moves downward along the slope of the seat cross member 2 when the engine unit 7 is dropped. Therefore, the effect of suppressing the deformation of the seat cross member 2 toward the passenger compartment can be enhanced.
[0052]
FIG. 6 shows a different example of the suspension member 11. The lateral member 15 has a substantially straight member general portion 15A and a rear end of the member general portion 15A in the vicinity of the connecting portion of the lateral member 15 and the cross member 16. The bent portions 17R and R formed by the member general portions 15A and the inclined portions 15B are used as the easily bent portions.
[0053]
The bent portions 17R and R constituting the easily bent portion are set in the vicinity of the connecting portion between the lateral member 15 and the cross member 16, and the lengths of the generally straight member general portion 15A and the inclined portion 15B are set. By increasing the ratio of L ₁ and L ₂ , the cross member 16 is substantially rotated when the lateral member 15 bends and deforms downward in a U-shape starting from the bent portions 17R and R at the time of a vehicle rear surface collision. The downward rotation angle θ of the inclined portion 15B as the center is large, and accordingly, the pulling-down force of the engine unit 7 by the torque rod 12 can be increased.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of the present invention.
FIG. 2 is a plan view showing an embodiment of the present invention.
FIG. 3 is a side view schematically showing one embodiment of the present invention.
FIG. 4 is a side view schematically showing a deformed state in the initial stage of a rear collision according to an embodiment of the present invention.
FIG. 5 is a side view schematically showing a deformed state in the latter half of the rear collision according to the embodiment of the present invention.
FIG. 6 is a schematic side view illustrating different examples of suspension members.
[Explanation of symbols]
2 Seat cross member (partition wall)
3 Car compartment 4 Engine room (mounted room)
6 Rear side member (side member)
6A kick-up club (member base)
7 Engine unit (power unit)
8 Mounting member 9 at the upper part of the power unit 9 Rotation control means 11 Suspension member 12 Torque rod 15 Lateral member 15A Member general part 15B Inclined part 16 Cross member 17F, 17R, 17R · R Easy bending part 18 Mounting member 0 at the lower part of the power unit Inertial main axis S Region from the middle part to the rear end of the _L side member θ Rotation angle of the inclined part

Claims

A structure in which the power unit is attached to a mounting room separated on the rear side of the passenger compartment by a rearwardly inclined partition wall,
Provide side members that can buckle forward with respect to a rear collision of the vehicle on both sides in the vehicle width direction of the mounting chamber,
The upper part of the power unit is supported on the side member so as to be rotatable in the front-rear direction via a mount member having a vibration isolating function, and the mount member is used for relative movement in the front-rear direction between the side member and the power unit at the time of a rear-end collision of the vehicle. It is configured so that it can be broken,
The lower part of the power unit is normally controlled to prevent the power unit from rotating in the front-rear direction with the mount member as a fulcrum, and to the power unit at the rear with the mount member as a fulcrum prior to the breakage of the mount member in the event of a rear-end collision of the vehicle supported by rotation control means for imparting rotational behavior to,
This rotation control means includes a pair of left and right lateral members whose front ends are supported on the lower side of the front part of the side members, and a cross member that is connected across the rear ends of these lateral members and supported at the lower rear end of the side members. A suspension member having,
A torque rod connecting the cross member and the lower part of the power unit;
In addition, the lateral member is provided with an easy-bending portion that facilitates downward bending of the intermediate portion in the front-rear direction of the lateral member when an axial load of a predetermined value or more acts upon a rear-end collision of the vehicle. Automotive power unit arrangement structure.

2. The power unit arrangement structure for an automobile according to claim 1, wherein the mount members are arranged substantially on the inertia main axis extending in the vehicle width direction of the power unit.

The easy-bending part is formed so as to rise obliquely upward from the rear end of the member general part of the lateral member in the vicinity of the substantially linear member general part of the lateral member and the connecting part of the lateral member and the cross member. 3. The power unit arrangement structure for an automobile according to claim 1 or 2 , characterized in that it is formed as a bent portion that is continuously provided with the inclined portion.

The power unit arrangement structure for an automobile according to any one of claims 1 to 3, wherein the torque rod and the cross member are connected via a mount member having a vibration isolation function.

Side members, the rigidity of the front end of the member base portion which is joined to the partition wall, any claim 1-4, characterized in that the stiffness of the region over the middle portion lowered for supporting the power unit from the rear end An automobile power unit arrangement structure according to claim 1.

The power unit arrangement structure for an automobile according to any one of claims 1 to 5 , wherein the partition wall is made of an extruded material that is extruded in a closed cross section in the vehicle width direction with a lightweight metal material.