JP3627558B2

JP3627558B2 - Auto body structure

Info

Publication number: JP3627558B2
Application number: JP02154899A
Authority: JP
Inventors: 文夫岡那; 隼次原崎
Original assignee: Mazda Motor Corp
Current assignee: Mazda Motor Corp
Priority date: 1999-01-29
Filing date: 1999-01-29
Publication date: 2005-03-09
Anticipated expiration: 2019-01-29
Also published as: JP2000219163A

Description

【０００１】
【発明の属する技術分野】
本発明は自動車の車体構造に関し、特に部品点数を削減して軽量化しつつ車体の剛性強度を高めたものに関する。
【０００２】
【従来の技術】
自動車の車体構造は、通常、前部車体構造、フロア構造、側部車体構造、カウル部構造、後部車体構造、ルーフ構造などからなる。
前記車体構造のうちの特に剛性、強度の必要な部位には、車体パネルと協働して閉断面を形成するやや厚手の板材からなるフレーム部材（左右１対のフロントフレーム、左右１対のリヤフレーム、複数のクロスメンバ等々）が設けられている。
【０００３】
前記フロントフレームは車体パネルとしてのホイールエプロンと協働して閉断面を形成し、リヤフレームは車体パネルであるリヤフロアパネルと協働して閉断面を形成している。ここで、前記フレーム部材を補強する為に、フレーム部材の内部に複数の補強部材が設けられるが、この補強部材はやや厚手の板部材をプレス成形加工したもので、補強部材には溶接接合する為の接合フランジが形成され、接合フランジをスポット溶接することでフレーム部材に溶接接合される。尚、前記フレーム部材には、フロントやリヤのサスペンションのサスペンション支持部材や、エンジンを搭載するエンジンマウント用サブフレームが連結される。
【０００４】
一方、特開平８−３３７１８２号、特開平９−１５０７５２号、特開平１０−９５３６４号、特開平１０−９５３６５号、特開平９−３０３４５号、特開平１０−１３９５０号、特開平８−１９２２３８号等には、ハイドロフォームにより閉断面フレームを成形し、その閉断面フレームで車体フレームを構成する技術が記載されている。ハイドロフォームは、図１３に示すように、鋼や軽金属等のパイプ素材５０を上型５１と下型５２とから成る成形型５３内に収容し流体圧により拡張成形して閉断面フレーム５４に成形する技術である。
【０００５】
【発明が解決しようとする課題】
従来の車体構造のうち、車体パネルと共に閉断面を形成するフレーム部材に、複数の板材からなる補強部材を組み込んだ構造では、補強部材をやや厚手の板材で構成し、接合フランジを介して溶接する構造であるため、補強の為の部品点数が多く、構造が複雑化し、補強部材の重量も重くなり、製作コストが高価になり、車体の軽量化を図る上で不利になる。
【０００６】
尚、前記公報には、ハイドロフォームで成形した閉断面フレームを用いてフレーム部材を作る技術は記載されているが、ハイドロフォームで成形した閉断面フレームを用いてフレーム部材を効果的に補強する技術については記載されてない。本発明の目的は、部品点数を削減して車体の軽量化を図りつつ車体の剛性強度を確実に高めることができる自動車の車体構造を提供することにある。
【０００７】
【課題を解決するための手段】
請求項１の自動車の車体構造は、車両の車体パネルと、この車体パネルに沿って前後方向に延び且つ車体パネルを含む閉断面を形成するフレーム部材とを備えた車体構造において、前記フレーム部材は、その前後部位の高さが変化したキックアップ部を備え、前記フレーム部材の閉断面内に、少なくとも前記キックアップ部の範囲にわたってフレーム部材に沿って配設されたパイプ状部材が取付けられ、前記パイプ状部材は前記キックアップ部の後方へ延びる後端部分を有し、この後端部分は断面「山」の字形の閉断面部に形成され、この断面「山」の字形の閉断面部の左右両側面と底面は前記フレーム部材の内面に沿う形状に形成されたことを特徴とするものである。
【０００８】
このフレーム部材の閉断面内に、フレーム部材の少なくともキックアップ部の範囲にわたって且つフレーム部材に沿って、フレーム部材を補強する為のパイプ状部材を取付けたので、１つのパイプ状部材でもってフレーム部材を効果的に補強することができる。即ち、パイプ状部材は閉断面構造で剛性強度に優れるためかなり薄肉状にすることができ、簡単にフレーム部材に溶接接合することもできるため、フレーム部材を補強する為の部品点数を削減でき、構造を簡単化でき、フレーム部材を補強する為の部材重量を小さくでき、製作コストを低減でき、車体重量を軽減する上でも有利である。
前記パイプ状部材は前記キックアップ部の後方へ延びる後端部分を有し、この後端部分は断面「山」の字形の閉断面部に形成され、この断面「山」の字形の閉断面部の左右両側面と底面は前記フレーム部材の内面に沿う形状に形成されている。
尚、前記フレーム部材のうちのキックアップ部のように湾曲した部分を、従来のような板材からなる補強部材で補強する場合は、複数の補強部材を組み合わせて補強することになり、部品点数が多く、構造が複雑化する。
【０００９】
請求項２の自動車の車体構造は、請求項１の発明において、前記パイプ状部材は車体パネルとフレーム部材の双方に接合されたことを特徴とするものである。基本的に請求項１と同様の作用を奏する。しかも、パイプ状部材が車体パネルとフレーム部材の双方に接合されたので、パイプ状部材に接合フランジを設けることなくパイプ状部材をフレーム部材と車体パネルとに強固に溶接接合することができ、パイプ状部材を介してフレーム部材の剛性、強度を確実に強化できる。
【００１２】
請求項３の自動車の車体構造は、請求項１又は２の発明において、前記車体パネルはプレス成形により成形された部材であり、前記パイプ状部材はハイドロフォームにより成形された部材であることを特徴とするものである。
金属製のパイプ素材を成形型内に収容してパイプ素材の内部に高圧の流体圧を充填するハイドロフォームにより成形することにより、ハイプ状部材を容易に成形することができ、閉断面構造のパイプ状部材は薄手のものでも剛性、強度に優れるため、このパイプ状部材でフレーム部材を補強することで、フレーム部材の剛性強度を確保することができ、車体重量の軽量化を図ることが可能になる。その他請求項１又は２と同様の作用を奏する。
【００１３】
【発明の実施の形態】
以下、本発明の実施の形態について図面を参照して説明する。
自動車（車両に相当する）の車体構造は、前部車体構造、フロア構造、側部車体構造、カウル部構造、後部車体構造、ルーフ構造などからなる。
図１に示すように、前部車体構造にはその重要な強度部材としての左右１対のフロントフレーム１（フレーム部材に相当する）が配設され、後部車体構造にはその重要な強度部材としての左右１対のリヤフレーム２（フレーム部材に相当する）が配設されている。最初に、フロントフレーム１について説明し、次にリヤフレーム部材２について説明する。
【００１４】
図１、図２に示すように、各フロントフレーム１は、エンジンルームの下部の左右の側部に前後方向向きに配設され、その前側約２／３部分に対して後側約１／３部分は段落ち状に一体的に形成され、図示のようにフロントフレーム１の後部の途中部にはその前後部位の高さが変化したキックアップ部１ａであって側面視ほぼクランク形状のキックアップ部１ａが形成されている。
【００１５】
フロントフレーム１は、断面溝形にプレス成形された厚さ約２〜４ｍｍの鋼製の板材からなり、その前側約２／３部分は車幅方向外側に開口する溝形をなし、その後部約１／３部分は上方に開口する溝形をなしている。フロントフレーム１の前側約２／３部分はホイールエプロン３（車体パネルに相当する）と協働してホイールエプロン３を含む閉断面を形成し、フロントフレーム１の後側約１／３部分はダッシュボード１２の下部とフロアパネル４（車体パネルに相当する）と協働してそれらを含む閉断面を形成している。
【００１６】
フロントフレーム１の接合フランジ１ｂは、ホイールエプロン３やダッシュボードの下部やフロアパネル４に適当間隔おきにスポット溶接することでそれらと一体的に接合される。尚、ホイールエプロン３、ダッシュボード１２、フロアーパネル４は、夫々プレス成形された厚さ約１〜２ｍｍの鋼製の板材からなる。
【００１７】
図２に示すように、各フロントフレーム１の閉断面内には、フロントフレーム１に沿って、補強の為の鋼製のパイプ状部材５（肉厚約１〜３ｍｍ）が設けられ、このパイプ状部材５は少なくともキックアップ部１ａの範囲とその前後の範囲に亙る状態に配設されている。つまり、パイプ状部材５は、フロントフレーム１の前端部分を除くほぼ全長に亙って設けられている。前記パイプ状部材５は、図３〜図７に黒丸印で示すように、フロントフレーム１、ホイールエプロン３、ダッシュボード１２及びフロアパネル４に複数の個所においてスポット溶接にて接合される。
【００１８】
即ち、図３〜図７に示すように、パイプ状部材５の前半部は、フロントフレーム１とホイールエプロン３の双方に溶接接合され、パイプ状部材５のうちのキックアップ部１ａの傾斜状部に対応する部分は、フロントフレーム１とダッシュパネル１２の双方に溶接接合され、パイプ状部材５のうちのほぼ水平な後端部分は、フロントフレーム１とフロアパネル４の双方に溶接接合される。
【００１９】
パイプ状部材５は、通称「ハイドロフォーム」と称する成形方法により成形されるものであるため、各位置における断面形状を、図４〜図７に示すように自由にフロントフレーム１内の溝の形状やその他の要請に適した自由の形状に設定することができる。即ち、図４に示すように、パイプ状部材５は、ホイールハウスの付近ではほぼ逆台形状断面をなし、その後方の位置では、図５、図６に示すようにほぼ矩形状断面をなし、キックアップ部１ａに対応する位置では図６に示すようにほぼ８角形断面をなし、キックアップ部１ａの後方へ延びる後端部分では図７に示すように断面「山」の字形の閉断面部に形成され、この断面「山」の字形の閉断面部の左右の両側面と底面はフロントフレーム１の内面に沿う形状に形成されている。
【００２０】
図５に示すように、パイプ状部材５の上下の壁部には、鉛直方向に貫通する貫通穴５ａが形成され、この貫通穴５ａに挿入されたボルト６が、そのネジ部６ａをフロントフレーム１よりも下方に突出させて設けられ、このボルト６によりエンジンを搭載して支持する為のエンジン搭載用サブフレーム（図示略）が連結される。
【００２１】
前記パイプ状部材５は鋼製のパイプ素材からハイドロフォームにより成形された部材であり、ホイールエプロン３、ダッシュパネル１２、フロアパネル４等は鋼製板材をプレス成形して成形された部材である。パイプ状部材５をハイドロフォームにより成形する場合、所定の成形型内にパイプ素材を収容し、そのパイプ素材内に高圧の油圧を充填することで成形することができる。そのため、１本の連続したパイプ素材から図２〜図７に示すような形状のパイプ状部材５を簡単に安価に成形することができる。しかも、パイプ状部材５によりフロントフレーム１を補強する場合には、従来の板材からなる補強部材を複数用いてフロントフレーム１を補強する場合に比べて、補強の為の部品点数を減らし、構造を格段に簡単化し、補強の為の部品重量を格段に軽減し、剛性と強度を大幅に向上させることができ、車体の軽量化を図ることができる。
【００２２】
次に、リヤフレーム２について説明する。
図１、図８に示すように、自動車の後部車体構造には、前後方向に延びる左右１対のリヤフレーム２が設けられ、これらリヤフレーム２はリヤフロアパネル７とトランクフロアパネル８（これらは車体パネルに相当し、板材をプレス成形して製作される）の下面側に配設されてリヤフロアパネル７やトランクフロアパネル８を含む閉断面を形成する。各リヤフレーム２は、断面溝形にプレス成形された厚さ約２〜４ｍｍの鋼製の板材からなり、各リヤフレーム２は、リヤフロアパネル７とトランクフロアパネル８の形状に沿って緩慢な階段状に後方上がりに傾斜した形状をなし、各リヤフレーム２の上端部には１対の接合フランジ２ａが形成され、これら接合フランジ２ａを介してリヤフロアパネル７とトランクフロアパネル８に溶接接合される。
【００２３】
図９〜図１２に示すように、各リヤフレーム２の閉断面内には、補強の為の鋼製のパイプ状部材９（肉厚約１〜３ｍｍ）がリヤフレーム２に沿って配設されている。但し、パイプ状部材９は、リヤフレーム２の閉断面内の前端部分と後端部分を除くほぼ全長に亙る状態に設けられている。このパイプ状部材９は複数個所においてスポット溶接によりリヤフレーム２とフロアパネル７，８に接合され、或いは、図１２に示すようにボルト・ナット１３によりリヤフレーム２に固定されている。尚、パイプ状部材９の上面の開口部９ａは組立の際にナットや工具を挿入する為に形成された作業孔である。
【００２４】
図８、図１０に示すように、パイプ状部材９の長さ方向の複数箇所において、パイプ状部材９の上下の壁部には、鉛直方向に貫通する貫通穴９ｂが形成され、この貫通穴９ｂにはボルト１０が上方から挿通され、そのネジ部がリヤフレーム２よりも下方に突出され、そのボルト１０によりサブフレーム１１がリヤフレーム２とパイプ状部材９に取付けられ、車両に設けられたサスペンションはサブフレーム１１を介してリヤフレーム２とパイプ状部材９に連結される。
【００２５】
図１１に示すように、パイプ状部材９の後端部の左右両側下部には、後方から衝突を受けたときに変形しやすくする為の複数のビード９ｃが適当間隔置きに形成されている。前記パイプ状部材５と同様に、このパイプ状部材９もハイドロフォームにより成形され、パイプ状部材５の前側約３／４部分は、図１０に示すように、リヤフレーム２の溝内にぴったりと嵌まる矩形断面をなし、パイプ状部材５の後側約１／４部分は、図９に示すようにリヤフレーム２の溝内に嵌まる６角形断面をなしている。
【００２６】
リヤフレーム２とパイプ状部材９においては、パイプ状部材９をハイドロフォームで成形するので、１本の連続したパイプ素材から図８〜図１２に示すような形状のパイプ状部材９を簡単に安価に成形することができる。
しかも、パイプ状部材９によりリヤフレーム２を補強する場合には、従来の板材からなる補強部材を複数用いてリヤフレーム２を補強する場合に比べて、補強の為の部品点数を減らし、構造を格段に簡単化し、補強の為の部品重量を格段に軽減し、剛性と強度を大幅に向上させることができ、車体の軽量化を図ることができる。
【００２７】
次に、本実施形態を部分的に変更した変更形態について説明する。
１）パイプ状部材５，９を、フロントフレームやリヤフレーム以外のフレーム部材であって、種々の車体パネルと協働した車体パネルを含む閉断面を形成する他のフレーム部材に設けることもできる。
２）車体の各部位における剛性、強度の違いに応じて、例えばパイプ状部材５，９或いはそれに代わるパイプ状部材を、肉厚や材質の異なる複数のパイプ素材を溶接接合して連続化したパイプ素材からハイドロフォームにより一体成形し、必要十分な剛性強度を確保するようにしてもよい。その他、本発明の趣旨を逸脱しない範囲において種々の変更を付加した形態で実施可能である。
【００２８】
【発明の効果】
請求項１の発明によれば、車体パネルに沿って延び車体パネルを含む閉断面を形成するフレーム部材の閉断面内に、フレーム部材の少なくともキックアップ部の範囲にわたって且つフレーム部材に沿って、フレーム部材を補強する為のパイプ状部材を取付けたので、１つのパイプ状部材でもってフレーム部材を効果的に補強することができる。即ち、パイプ状部材は閉断面構造で剛性強度に優れるためかなり薄肉状にすることができ、簡単にフレーム部材に溶接接合することもできるため、フレーム部材を補強する為の部品点数を削減でき、構造を簡単化でき、フレーム部材を補強する為の部材重量を小さくでき、製作コストを低減でき、車体重量を軽減する上でも有利である。
前記パイプ状部材は前記キックアップ部の後方へ延びる後端部分を有し、この後端部分は断面「山」の字形の閉断面部に形成され、この断面「山」の字形の閉断面部の左右両側面と底面は前記フレーム部材の内面に沿う形状に形成されたので、断面「山」の字形の閉断面部の左右両側面と底面を前記フレーム部材にスポット溶接等で強固に接合することができる。
【００２９】
請求項２の発明によれば、パイプ状部材を車体パネルとフレーム部材の双方に接合したので、パイプ状部材に接合フランジを設けることなくパイプ状部材をフレーム部材と車体パネルとに強固に溶接接合することができ、パイプ状部材を介してフレーム部材の剛性、強度を確実に強化できる。その他請求項１と同様の効果を奏する。
【００３２】
請求項３の発明によれば、車体パネルはプレス成形により成形された部材であり、パイプ状部材はハイドロフォームにより形成された部材であるが、金属製のパイプ素材を成形型内に収容してパイプ素材の内部に高圧の流体圧を充填するハイドロフォームにより成形することにより、パイプ状部材を容易に成形することができ、閉断面構造のパイプ状部材は薄手のもので剛性、強度に優れるため、このパイプ状部材でフレーム部材を補強することで、車体フレームとフレーム部材とで形成される閉断面部の剛性強度を格段に高めることができ、車体重量の軽量化を図ることができる。その他請求項１又は２と同様の効果を奏する。
【図面の簡単な説明】
【図１】本発明の実施形態に係る自動車の車体構造の概略分解斜視図である。
【図２】フロントフレーム拡大斜視図である。
【図３】図２のＩＩＩ − ＩＩＩ線断面図である。
【図４】図２のＩＶ−ＩＶ線断面図である。
【図５】図２のＶ − Ｖ線断面図である。
【図６】図２のＶＩ−ＶＩ線断面図である。
【図７】図２のＶＩＩ − ＶＩＩ線断面図である。
【図８】リヤフレームの拡大斜視図である。
【図９】図８のＩＸ−ＩＸ線断面図である。
【図１０】図８のＸ −Ｘ線断面図である。
【図１１】リヤフレームを補強するパイプ状部材の後端部の拡大斜視図である。
【図１２】図１１のＸＩＩ −ＸＩＩ線断面図である。
【図１３】（ａ）はハイドロフォームによる成形を行う成形装置の正面図、（ｂ）は成形型とパイプ素材の断面図、（ｃ）は流体圧で拡張成形後の状態における成形型とパイプ素材の断面図である。
【符号の説明】
１フロントフレーム
１ａキックアップ部
２リヤフレーム
３ホイールエプロン
４フロアパネル
５，９パイプ状部材
７リヤフロアパネル
８トランクフロアパネル
１１サブフレーム[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle body structure of an automobile, and more particularly, to a vehicle body structure having a reduced rigidity and weight while reducing the number of parts.
[0002]
[Prior art]
The vehicle body structure of an automobile usually includes a front body structure, a floor structure, a side body structure, a cowl structure, a rear body structure, a roof structure, and the like.
Of the vehicle body structure, particularly rigid and strong parts need to have frame members (a pair of left and right front frames, a pair of left and right rear frames) that are formed of slightly thicker plates that form a closed cross-section in cooperation with the vehicle body panel. A frame, a plurality of cross members, etc.).
[0003]
The front frame forms a closed section in cooperation with a wheel apron as a body panel, and the rear frame forms a closed section in cooperation with a rear floor panel which is a body panel. Here, in order to reinforce the frame member, a plurality of reinforcing members are provided inside the frame member. This reinforcing member is formed by press-molding a slightly thick plate member, and is welded to the reinforcing member. A joining flange is formed, and the joining flange is welded to the frame member by spot welding. The frame member is connected to a suspension support member for front and rear suspensions and an engine mount subframe for mounting an engine.
[0004]
On the other hand, JP-A-8-337182, JP-A-9-150752, JP-A-10-95364, JP-A-10-95365, JP-A-9-30345, JP-A-10-13950, JP-A-8-192238. Describe a technique in which a closed cross-section frame is formed by hydroforming, and a vehicle body frame is formed by the closed cross-section frame. As shown in FIG. 13, the hydroform accommodates a pipe material 50 such as steel or light metal in a forming die 53 composed of an upper die 51 and a lower die 52, and is expanded and formed by a fluid pressure into a closed cross-section frame 54. Technology.
[0005]
[Problems to be solved by the invention]
In the structure of a conventional vehicle body structure in which a reinforcing member made of a plurality of plate members is incorporated in a frame member that forms a closed section together with a vehicle body panel, the reinforcing member is made of a slightly thicker plate member and is welded via a joining flange. Because of the structure, the number of parts for reinforcement is large, the structure is complicated, the weight of the reinforcing member is increased, the manufacturing cost is increased, and this is disadvantageous in reducing the weight of the vehicle body.
[0006]
The above publication describes a technique for making a frame member using a closed cross-section frame formed of hydrofoam, but a technique for effectively reinforcing the frame member using a closed cross-section frame formed of hydrofoam. Is not described. An object of the present invention is to provide a vehicle body structure for an automobile capable of reliably increasing the rigidity and strength of the vehicle body while reducing the number of parts and reducing the weight of the vehicle body.
[0007]
[Means for Solving the Problems]
The vehicle body structure according to claim 1 is a vehicle body structure including a vehicle body panel of the vehicle and a frame member that extends in the front-rear direction along the vehicle body panel and forms a closed cross section including the vehicle body panel. , before and after with the kick-up portion which height changes in site, in closed section of the frame member is mounted at least the kick-up portion a pipe-like member disposed along the frame member over a range of, the The pipe-shaped member has a rear end portion extending rearward of the kick-up portion, and the rear end portion is formed in a closed cross-section portion having a cross-section “mountain” shape. The left and right side surfaces and the bottom surface are formed in a shape along the inner surface of the frame member .
[0008]
Since a pipe-shaped member for reinforcing the frame member is attached within the closed cross section of the frame member over at least the range of the kick-up portion of the frame member and along the frame member, the frame member can be formed with one pipe-shaped member. Can be effectively reinforced. That is, since the pipe-shaped member has a closed cross-sectional structure and is excellent in rigidity and strength, it can be made quite thin, and can be easily welded to the frame member, so the number of parts for reinforcing the frame member can be reduced, The structure can be simplified, the weight of the member for reinforcing the frame member can be reduced, the manufacturing cost can be reduced, and this is advantageous in reducing the weight of the vehicle body.
The pipe-shaped member has a rear end portion extending rearward of the kick-up portion, and the rear end portion is formed in a closed cross-section portion having a cross-section “mountain” shape, and this cross-section “mountain” -shaped closed cross-section portion is formed. The left and right side surfaces and the bottom surface are formed in a shape along the inner surface of the frame member.
In addition, when reinforcing a curved portion such as a kick-up portion of the frame member with a reinforcing member made of a conventional plate material, it is reinforced by combining a plurality of reinforcing members, and the number of parts is reduced. In many cases, the structure becomes complicated.
[0009]
A vehicle body structure according to a second aspect of the present invention is the vehicle body structure according to the first aspect, wherein the pipe-shaped member is joined to both the vehicle body panel and the frame member . Performing an operation similar to the basic manner Claim 1. Moreover, since the pipe-like member is joined to both the vehicle body panel and the frame member, the pipe-like member can be firmly welded and joined to the frame member and the vehicle body panel without providing a joint flange on the pipe-like member. The rigidity and strength of the frame member can be reliably reinforced through the shaped member.
[0012]
According to a third aspect of the present invention, there is provided a vehicle body structure according to the first or second aspect, wherein the vehicle body panel is a member formed by press molding, and the pipe-shaped member is a member formed by hydroforming. It is what.
A pipe with a closed cross-section structure can be formed easily by housing a metal pipe material in a mold and forming it with a hydroform that fills the inside of the pipe material with a high fluid pressure. Even if a thin member is thin, it has excellent rigidity and strength. By reinforcing the frame member with this pipe-like member, the rigidity and strength of the frame member can be secured, and the weight of the vehicle body can be reduced. Become. Other effects similar to those of the first or second aspect are achieved.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The body structure of an automobile (corresponding to a vehicle) includes a front body structure, a floor structure, a side body structure, a cowl structure, a rear body structure, a roof structure, and the like.
As shown in FIG. 1, the front body structure is provided with a pair of left and right front frames 1 (corresponding to frame members) as its important strength members, and the rear body structure as its important strength members. A pair of left and right rear frames 2 (corresponding to frame members) are disposed. First, the front frame 1 will be described, and then the rear frame member 2 will be described.
[0014]
As shown in FIG. 1 and FIG. 2, each front frame 1 is disposed in the front-rear direction on the left and right sides of the lower part of the engine room, and about 1/3 of the rear side with respect to about 2/3 of the front side. The part is integrally formed in a stepped shape, and as shown in the figure, a kick-up part 1a in which the height of the front and rear parts thereof is changed in the middle part of the rear part of the front frame 1 and is substantially crank-shaped kick-up in side view. Part 1a is formed.
[0015]
The front frame 1 is made of a steel plate material having a thickness of about 2 to 4 mm that is press-formed into a cross-sectional groove shape, and the front side approximately 2/3 portion has a groove shape that opens outward in the vehicle width direction, and the rear portion is approximately The 1/3 portion has a groove shape opening upward. About 2/3 of the front side of the front frame 1 cooperates with the wheel apron 3 (corresponding to the vehicle body panel) to form a closed cross section including the wheel apron 3, and about 1/3 of the rear side of the front frame 1 is a dash. A closed cross section including the lower portion of the board 12 and the floor panel 4 (corresponding to a vehicle body panel) is formed.
[0016]
The joining flange 1b of the front frame 1 is integrally joined to the wheel apron 3, the lower part of the dashboard, and the floor panel 4 by spot welding at appropriate intervals. The wheel apron 3, the dashboard 12, and the floor panel 4 are each made of a steel plate having a thickness of about 1 to 2 mm that is press-formed.
[0017]
As shown in FIG. 2, a steel pipe-like member 5 (thickness of about 1 to 3 mm) for reinforcement is provided along the front frame 1 in the closed cross section of each front frame 1. The member 5 is arranged in a state extending at least in the range of the kick-up portion 1a and the range before and after the kick-up portion 1a. That is, the pipe-like member 5 is provided over almost the entire length excluding the front end portion of the front frame 1. The pipe-like member 5 is joined to the front frame 1, the wheel apron 3, the dashboard 12, and the floor panel 4 by spot welding at a plurality of locations, as indicated by black circles in FIGS.
[0018]
That is, as shown in FIGS. 3 to 7, the front half of the pipe-shaped member 5 is welded to both the front frame 1 and the wheel apron 3, and the inclined portion of the kick-up portion 1 a of the pipe-shaped member 5. The portion corresponding to is welded and joined to both the front frame 1 and the dash panel 12, and the substantially horizontal rear end portion of the pipe-like member 5 is welded and joined to both the front frame 1 and the floor panel 4.
[0019]
Since the pipe-like member 5 is formed by a forming method called “hydroform”, the cross-sectional shape at each position can be freely changed to the shape of the groove in the front frame 1 as shown in FIGS. It can be set to a free shape suitable for other requirements. That is, as shown in FIG. 4, the pipe-shaped member 5 has a substantially inverted trapezoidal cross section in the vicinity of the wheel house, and has a substantially rectangular cross section as shown in FIGS. 6 has a substantially octagonal cross section as shown in FIG. 6 at the position corresponding to the kick-up portion 1a, and the rear end portion extending rearward of the kick-up portion 1a has a closed cross-section having a cross-section “mountain” shape as shown in FIG. The left and right side surfaces and the bottom surface of the closed cross-sectional portion having a cross-sectional “mountain” shape are formed along the inner surface of the front frame 1 .
[0020]
As shown in FIG. 5, the upper and lower wall portions of the pipe-shaped member 5 are formed with through holes 5a penetrating in the vertical direction, and bolts 6 inserted into the through holes 5a connect the screw portions 6a to the front frame. An engine mounting sub-frame (not shown) for mounting and supporting the engine is connected by this bolt 6.
[0021]
The pipe-shaped member 5 is a member formed by hydroforming from a steel pipe material, and the wheel apron 3, the dash panel 12, the floor panel 4 and the like are members formed by press-molding a steel plate material. When the pipe-shaped member 5 is molded by hydroforming, it can be molded by storing the pipe material in a predetermined mold and filling the pipe material with high pressure hydraulic pressure. Therefore, the pipe-like member 5 having a shape as shown in FIGS. 2 to 7 can be easily and inexpensively formed from one continuous pipe material. Moreover, when the front frame 1 is reinforced by the pipe-shaped member 5, the number of parts for reinforcement is reduced and the structure is reduced compared to the case where the front frame 1 is reinforced by using a plurality of reinforcing members made of a conventional plate material. It can be greatly simplified, the weight of parts for reinforcement can be greatly reduced, rigidity and strength can be greatly improved, and the weight of the vehicle body can be reduced.
[0022]
Next, the rear frame 2 will be described.
As shown in FIGS. 1 and 8, a rear body structure of an automobile is provided with a pair of left and right rear frames 2 extending in the front-rear direction. These rear frames 2 are composed of a rear floor panel 7 and a trunk floor panel 8 (these are vehicle bodies). A closed section including the rear floor panel 7 and the trunk floor panel 8 is formed by being disposed on the lower surface side of the sheet material (corresponding to a panel, which is manufactured by press-molding a plate material). Each rear frame 2 is made of a steel plate material having a thickness of about 2 to 4 mm press-formed into a groove shape in cross section, and each rear frame 2 is a slow staircase along the shape of the rear floor panel 7 and the trunk floor panel 8. Each rear frame 2 has a pair of joint flanges 2a formed at the upper end of each rear frame 2, and is welded to the rear floor panel 7 and the trunk floor panel 8 via these joint flanges 2a. .
[0023]
As shown in FIGS. 9 to 12, a steel pipe-like member 9 (thickness: about 1 to 3 mm) for reinforcement is disposed along the rear frame 2 in the closed cross section of each rear frame 2. ing. However, the pipe-like member 9 is provided over a substantially entire length excluding the front end portion and the rear end portion in the closed cross section of the rear frame 2. The pipe-like member 9 is joined to the rear frame 2 and the floor panels 7 and 8 by spot welding at a plurality of locations, or is fixed to the rear frame 2 by bolts and nuts 13 as shown in FIG. The opening 9a on the upper surface of the pipe-like member 9 is a work hole formed for inserting a nut or a tool during assembly.
[0024]
As shown in FIG. 8 and FIG. 10, in a plurality of locations in the length direction of the pipe-shaped member 9, through-holes 9 b penetrating in the vertical direction are formed in the upper and lower wall portions of the pipe-shaped member 9. A bolt 10 is inserted through 9b from above, and its threaded portion projects downward from the rear frame 2, and the subframe 11 is attached to the rear frame 2 and the pipe-like member 9 by the bolt 10 and is provided on the vehicle. The suspension is connected to the rear frame 2 and the pipe-like member 9 via the subframe 11.
[0025]
As shown in FIG. 11, a plurality of beads 9 c are formed at appropriate intervals on the lower left and right sides of the rear end portion of the pipe-shaped member 9 to facilitate deformation when subjected to a collision from the rear. Similar to the pipe-like member 5, this pipe-like member 9 is also formed by hydroforming, and the front side approximately 3/4 portion of the pipe-like member 5 is fitted in the groove of the rear frame 2 as shown in FIG. A rectangular cross section that fits in is formed, and a rear quarter portion of the pipe-like member 5 has a hexagonal cross section that fits in the groove of the rear frame 2 as shown in FIG.
[0026]
In the rear frame 2 and the pipe-shaped member 9, since the pipe-shaped member 9 is formed by hydroforming, the pipe-shaped member 9 having the shape as shown in FIGS. Can be molded.
In addition, when the rear frame 2 is reinforced by the pipe-shaped member 9, the number of parts for reinforcement is reduced and the structure is reduced compared to the case where the rear frame 2 is reinforced by using a plurality of reinforcing members made of a conventional plate material. It can be greatly simplified, the weight of parts for reinforcement can be greatly reduced, rigidity and strength can be greatly improved, and the weight of the vehicle body can be reduced.
[0027]
Next, a modified embodiment in which the present embodiment is partially modified will be described.
1) The pipe-like members 5 and 9 can be provided on other frame members which are frame members other than the front frame and the rear frame and form a closed cross section including a vehicle body panel that cooperates with various vehicle body panels.
2) A pipe in which, for example, pipe-like members 5 and 9 or pipe-like members instead thereof are welded and joined together by welding a plurality of pipe materials having different thicknesses and materials in accordance with differences in rigidity and strength in each part of the vehicle body. The material may be integrally formed with a hydroform to ensure the necessary and sufficient rigidity and strength. In addition, various modifications can be added without departing from the spirit of the present invention.
[0028]
【The invention's effect】
According to the invention of claim 1, the frame extends along at least the kick-up portion of the frame member and along the frame member within the closed cross section of the frame member that extends along the vehicle body panel and forms a closed cross section including the vehicle body panel. Since the pipe-shaped member for reinforcing the member is attached, the frame member can be effectively reinforced with one pipe-shaped member. That is, since the pipe-shaped member has a closed cross-sectional structure and is excellent in rigidity and strength, it can be made quite thin, and can be easily welded to the frame member, so the number of parts for reinforcing the frame member can be reduced, The structure can be simplified, the weight of the member for reinforcing the frame member can be reduced, the manufacturing cost can be reduced, and this is advantageous in reducing the weight of the vehicle body.
The pipe-shaped member has a rear end portion extending rearward of the kick-up portion, and the rear end portion is formed in a closed cross-section portion having a cross-section “mountain” shape, and this cross-section “mountain” -shaped closed cross-section portion is formed. Since both the left and right side surfaces and the bottom surface of the frame are formed along the inner surface of the frame member, the left and right side surfaces and the bottom surface of the closed cross-section having a cross-section “mountain” shape are firmly joined to the frame member by spot welding or the like. be able to.
[0029]
According to the invention of claim 2, since the joining pipes like member to both the vehicle body panel and the frame member, rigidly to the frame member and the vehicle body panel pipe-like member without providing the joint flange to the pipe-like member welded It is possible to join, and the rigidity and strength of the frame member can be reliably reinforced through the pipe-like member. Other effects similar to those of the first aspect are obtained.
[0032]
According to the invention of claim 3 , the vehicle body panel is a member formed by press molding, and the pipe-shaped member is a member formed by hydroforming, but the metal pipe material is accommodated in the mold. By forming the pipe material with a hydroform that fills the inside of the pipe with a high fluid pressure, the pipe-shaped member can be easily formed. The pipe-shaped member with a closed cross-sectional structure is thin and has excellent rigidity and strength. By reinforcing the frame member with this pipe-shaped member, the rigidity and strength of the closed cross section formed by the vehicle body frame and the frame member can be significantly increased, and the weight of the vehicle body can be reduced. Other effects similar to those of the first or second aspect are achieved.
[Brief description of the drawings]
FIG. 1 is a schematic exploded perspective view of a vehicle body structure of an automobile according to an embodiment of the present invention.
FIG. 2 is an enlarged perspective view of a front frame.
3 is a cross-sectional view taken along line III-III in FIG.
4 is a cross-sectional view taken along line IV-IV in FIG.
5 is a cross-sectional view taken along the line V-V in FIG. 2;
6 is a cross-sectional view taken along line VI-VI in FIG.
7 is a sectional view taken along line VII-VII in FIG.
FIG. 8 is an enlarged perspective view of a rear frame.
9 is a cross-sectional view taken along line IX-IX in FIG.
10 is a cross-sectional view taken along line XX in FIG.
FIG. 11 is an enlarged perspective view of a rear end portion of a pipe-shaped member that reinforces the rear frame.
12 is a cross-sectional view taken along line XII-XII in FIG.
13A is a front view of a molding apparatus that performs molding by hydroforming, FIG. 13B is a cross-sectional view of a molding die and a pipe material, and FIG. 13C is a molding die and pipe in a state after expansion molding by fluid pressure. It is sectional drawing of a raw material.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Front frame 1a Kick-up part 2 Rear frame 3 Wheel apron 4 Floor panel 5, 9 Pipe-shaped member 7 Rear floor panel 8 Trunk floor panel 11 Sub frame

Claims

In a vehicle body structure including a vehicle body panel and a frame member that extends in the front-rear direction along the vehicle body panel and forms a closed section including the vehicle body panel,
The frame member includes a kick-up portion in which the height of the front and rear portions thereof is changed,
In the closed cross section of the frame member, a pipe-like member disposed along the frame member is attached over at least the range of the kick-up portion,
The pipe-shaped member has a rear end portion extending rearward of the kick-up portion, and the rear end portion is formed in a closed cross-section portion having a cross-section “mountain” shape, and this cross-section “mountain” -shaped closed cross-section portion is formed. The left and right side surfaces and the bottom surface of the frame member are formed in a shape along the inner surface of the frame member.
A vehicle body structure characterized by that.

2. The vehicle body structure according to claim 1, wherein the pipe-shaped member is joined to both the vehicle body panel and the frame member.

The vehicle body structure according to claim 1 or 2 , wherein the vehicle body panel is a member formed by press molding, and the pipe-shaped member is a member formed by hydroforming.