JP4194142B2

JP4194142B2 - Body floor structure and method of manufacturing body floor structure

Info

Publication number: JP4194142B2
Application number: JP28467198A
Authority: JP
Inventors: 昌和澤田
Original assignee: Fuji Jukogyo KK
Current assignee: Subaru Corp
Priority date: 1998-10-07
Filing date: 1998-10-07
Publication date: 2008-12-10
Anticipated expiration: 2018-10-07
Also published as: JP2000108947A

Description

【０００１】
【発明の属する技術分野】
本発明は、車体フロア構造及び車体フロア構造の製造方法に関し、特に車体のフロントフロアパネルとリヤフロアパネルとを結合する車体フロア構造及び車体フロア構造の製造方法に関する。
【０００２】
【従来の技術】
車体のフロアは、一般にフロアの下方に燃料タンクを配置することから、フロアの後半分であるリヤフロアパネルを、前半分であるフロントフロアパネルよりも高く段差を設けて接続したものがある。この場合、通常、リヤフロアパネルに形成された段差部の裏側にクロスメンバを結合して段差部とクロスメンバとによって車幅方向に延在する閉断面を形成して剛性の向上を図っている。
【０００３】
一方、更にフロアの剛性向上を図るために、実開平１−６８９９１号公報に開示され、かつ図７に斜視図を示すようにフロントフロアパネル１０１のトンネル部１０２の後端縁１０３を車幅方向に沿って広げると共に、両側方向に移行するに従って漸次低くなるように形成する一方、リヤフロアパネル１０５の段差部１０６に形成したリブ１０７を後端縁１０３に重合可能なように形成し、これら後端縁１０３とリブ１０７との間にクロスメンバ１０８のフランジ１０９を挟んで後端縁１０３と、リブ１０７と、フランジ１０９とを共にスポット溶接結合することによってフロア１００の横方向の剛性を向上する車両用フロア構造が提案されている。
【０００４】
また、実開平２−５６７８７号公報に開示され、かつ図８に斜視図を示すように、トンネル部１０２を有するフロントフロアパネル１１１の後端部に、リヤフロアパネル１１５を結合すると共に、リヤフロアパネル１１１と協働して車体幅方向に延在する閉断面を形成するクロスメンバ１０７を備えた車体フロア構造において、上記トンネル部１０２の下面に沿ってクロスメンバ１０７から前方に向けて延在する補強部１０８を延設し、トンネル１０２の下面と補強部１０８とによって閉断面を形成してフロントフロアパネル１１１とリヤフロアパネル１１５の結合強度を確保する車体フロア構造が提案されている。
【０００５】
【発明が解決しようとする課題】
上記実開平１−６８９９１号公報に開示される車両用フロア構造によりると、フロントフロアパネルのトンネル部の後端縁と、リヤフロアパネルに形成したリブと、クロスメンバのフランジとを共にスポット溶接結合することによってリヤフロアパネルの形状を拘束してフロアの車体幅方向の剛性向上を図っている。
【０００６】
しかし、リヤフロアパネルとクロスメンバとによって車体幅方向に延在する閉断面形状を形成するものの、車体側方から過大な衝撃荷重が作用した際、サイドシルを介してリヤフロアパネルとクロスメンバに作用する荷重によってリヤフロアパネル及びクロスメンバが変形し、その衝撃荷重をリヤフロア及びクロスメンバを介して反対側のサイドシルや他の車体部材に効率的に分散伝達することが妨げられてサイドシル、ひいてはリヤクォータパネル等の側部車体部材が車室内に進入することが懸念される。
【０００７】
また、フロントフロアパネルとリヤフロアパネルとの結合が車体幅方向に延在するフロントフロアパネルの後端縁と、リヤフロアパネルの段差部に形成したリブと、クロスメンバのフランジとを重合してスポット溶接結合することから、車体前後方向、例えば前方から過大な衝撃荷重は作用すると、車体前部で吸収しきれない衝撃荷重がトーボード等を介してフロントフロアパネルの前部に前方から作用し、フロントフロア及びフロントフロアパネルとリヤフロアパネルとの接合部に応力が集中して該部が座屈変形してフロアに結合されるサイドシルやその他の車体部材に効率的に荷重が分散伝達されず車体フロアが過度に変形することが懸念される。
【０００８】
また、実開平２−５６７８７号の車体フロア構造によると、リヤフロアパネルとクロスメンバによって車幅方向に延在する閉断面を形成してリヤフロアパネルの形状を拘束すると共に、フロントフロアパネルとリヤフロアパネルがクロスメンバに形成された補強部によって結合されてフロントフロアパネルとリヤフロアパネルとの結合強度の向上を図っている。
【０００９】
しかし、上記実開平１−６８９９１号の車体フロアと同様に、リヤフロアパネルとクロスメンバとによって車体幅方向に延在する閉断面形状を形成するものの、車体側方から過大な衝撃荷重が作用した際、サイドシルを介してリヤフロアパネルとクロスメンバに作用する荷重によってフロアが変形すると共に車体前後方向からの過大な衝撃荷重によってフロントフロアが変形し、その結果衝撃荷重を他の車体部材に効率的に分散伝達することが妨げられ側部車体部材が車室内に進入することが懸念される。
【００１０】
一方、車体側方及び車体前後方向からの衝撃荷重を効率よく分散伝達することによって車体フロアの変形を防止して室内への影響を軽減すべく車体フロアの一層の剛性向上が望まれている。
【００１１】
従って、かかる点に鑑みなされた本発明の目的は、車体側方及び車体前後方向から車体に衝撃荷重が作用した際、充分に車体フロアの変形を防止して安全性が確保し得る車体フロア構造及び車体フロア構造の製造方法を提供することにある。
【００１２】
【課題を解決するための手段】
上記目的を達成する請求項１に記載の車体フロア構造は、車体前後方向に延在するトンネル部が形成されたフロントフロアパネルの後部に、リヤフロア面の前部に段差部が形成されたリヤフロアパネルの前部を結合すると共に、上記段差部下端とリヤフロア面との間にクロスメンバを架設して車体幅方向に延在する閉断面形状を形成する車体フロア構造において、フロントフロア面の中央部に車体前後方向に延在するトンネル部が形成されたフロントフロアパネルと、上記トンネル部の頂部下面に沿って車体前後方向に配設されたトンネルリンフォースと、リヤフロア面の前部に段差部が形成され、該段差部の下端が上記トンネル部を含むフロントフロア後部に結合されたリヤフロアパネルと、該リヤフロアパネルの段差部と結合して車体幅方向に延在する上縁及び下縁に形成されたフランジを有し、上記段差部と協働して車体幅方向に延在する第１閉断面形状を形成するとともに該下縁が上記トンネル部と結合するフロアリンフォースと、上記段差部とリヤフロア面との間に架設されて上記フロアリンフォースを収容して車体幅方向に延在する第２閉断面形状を形成するクロスメンバと、リヤフロアの段差部下部とフロアリンフォースとクロスメンバとの少なくとも１つに上記トンネル部の頂部下面に沿って車体前方に延設されて上記トンネル部及びトンネルリンフォースに結合するトンネル結合部とを備えたことを特徴とする。
【００１３】
請求項１の発明によると、リヤフロアパネルとフロアリンフォースとの協働によって車体幅方向に延在する第１閉断面形状を形成すると共に、リヤフロアパネルとクロスメンバとの協働によって上記第１閉断面形状を収容して車体幅方向に延在する第２閉断面形状を形成することから特にフロアの車体幅方向の形状が拘束され、車体側方向から作用する衝撃荷重に対してフロアの変形が抑制されて衝撃荷重を他の車体部材に効率的に分散伝達することができる。
【００１４】
一方、フロントフロアを形成するフロントフロアパネルのトンネル部がトンネルリンフォースによって補剛され、かつトンネル部及びトンネルリンフォースにリヤフロア部を形成するリヤフロア、フロアリンフォース、クロスメンバの少なくとも１つにトンネル部に沿って延設されたトンネル結合部が結合することからフロントフロアの前後方向の剛性が確保されると共に、フロントフロア部とリヤフロア部の結合剛性が確保されて特にフロアの車体前後方向の形状が拘束されて車体前後方向から作用する衝撃荷重に対してフロアの変形が抑制されて衝撃荷重を他の車体部材に効率的に分散伝達することができる。
【００１５】
上記目的を達成する請求項２に記載の車体フロア構造の発明は、車体前後方向に延在するトンネル部が形成されたフロントフロアパネルの後部に、リヤフロア面の前部に段差部が形成されたリヤフロアパネルの前部を結合すると共に、上記段差部下端とリヤフロア面との間にクロスメンバを架設して車体幅方向に延在する閉断面形状を形成する車体フロア構造において、フロントフロア面の中央部に車体前後方向に延在するトンネル部が形成されたフロントフロアパネルと、上記トンネル部の頂部下面に沿って車体前後方向に配設されたトンネルリンフォースと、リヤフロア面の前部に段差部が形成されたリヤフロアパネルと、該リヤフロアパネルの段差部と結合して車体幅方向に延在する上縁及び下縁に形成されたフランジを有し、上記段差部と協働して車体幅方向に延在する第１閉断面形状を形成するとともに該下縁が上記トンネル部と結合するフロアリンフォースと、上記段差部とリヤフロア面との間に架設されて上記フロアリンフォースを収容して車体幅方向に延在する第２閉断面形状を形成すると共に、上記トンネル部の頂部下面に沿って車体前方に延設されたトンネル結合部を有するクロスメンバとを備え、上記リヤフロアパネルの段差部下部とフロアリンフォースとクロスメンバとが共にスポット溶接結合され、上記トンネル部の頂部とトンネルリンフォースとクロスメンバのトンネル結合部とが共にスポット溶接結合され、かつ上記トンネル部の頂部とリヤフロアパネルの段差部下部とクロスメンバとが共にスポット溶接結合されたことを特徴とする。
【００１６】
請求項２の発明は、請求項１の発明をより具体化したものであって、請求項１の効果に加え、リヤフロアパネルの段差部下縁とフロアリンフォースとクロスメンバとを共にスポット溶接結合し、トンネル部の頂部とトンネルリンフォースとクロスメンバのトンネル結合部を共にスポット溶接結合し、かつトンネル部の頂部とリヤフロアパネルの段差部下縁とクロスメンバとを共にスポット溶接結合することによって互いに構成部材が結合され、各スポット溶接結合部において重合される結合部材が３枚以内であり、スポット溶接時の加圧力及び電流密度が充分に確保されて安定した結合強度が得られる。
【００１７】
請求項３に記載の発明は、請求項２の車体フロア構造において、上記リヤフロアパネルの段差部下縁とフロアリンフォースとクロスメンバとのスポット溶接結合は、上記フロアリンスフォースの端縁に、上記トンネル部の頂部に対応する部分に重合可能に突設された取付フランジと、上記リヤフロアパネルの段差部下部に形成された前部フランジと、上記クロスメンバのトンネル結合部に形成された前部結合部とを重合せしめ、該重合する取付フランジ、前部フランジ、前部結合部を共にスポット溶接結合したことを特徴とする。
【００１８】
この請求項３の発明によると、リヤフロアパネルの段差部下縁とフロアリンフォースとクロスメンバとに各々形成された取付フランジ、前部フランジ、前部結合部をスポット溶接結合することによって容易に、リヤフロアパネルの段差部下縁とフロアリンフォースとクロスメンバとが容易かつ確実に結合される。
【００１９】
請求項４に記載された発明は、請求項２または３の車体フロア構造において、上記トンネル部の頂部とリヤフロアパネルの段差部下縁とクロスメンバとのスポット溶接結合は、上記トンネル部に形成された後端フランジと、上記リヤフロアパネルの段差部下縁に形成された前部フランジと、上記クロスメンバのトンネル結合部に形成された前部結合部とを重合せしめ、該重合する後端フランジと、前部フランジと、前部結合部を共にスポット溶接結合したことを特徴とする。
【００２０】
請求項４の発明によると、トンネル部に形成された後端フランジと、リヤフロアパネルに形成された前部フランジと、上記クロスメンバのトンネル結合部に形成された前部結合部とを溶接結合することによって、トンネル部の頂部とリヤフロアパネルの段差部下縁とクロスメンバとが容易かつ確実に結合される。
【００２１】
請求項５に記載の発明は、請求項２または３の車体フロア構造において、上記リヤフロアパネルの段差部下縁とフロアリンフォースとクロスメンバとのスポット溶接結合は、上記フロアリンスフォースの端縁に、上記トンネル部の頂部に対応する部分に重合可能に互いに離間して突設された複数の取付フランジと、上記リヤフロアパネルの段差部下縁に形成された前部フランジと、上記クロスメンバのトンネル結合部に形成された前部結合部とを重合せしめ、該重合する取付フランジ、前部フランジ、前部結合部を共にスポット溶接結合すると共に、上記トンネル部の頂部とリヤフロアパネルの段差部下縁とクロスメンバとのスポット溶接結合は、上記トンネル部に形成された後部フランジと、上記リヤフロアパネルの段差部下縁に形成された上記前部フランジと、上記クロスメンバのトンネル結合部に形成された上記前部結合部とを重合せしめ、該重合する後部フランジと、前部フランジと、前部結合部を上記複数の取付フランジ間の非重複部位においてスポット溶接結合したことを特徴とする。
【００２２】
請求項５の発明によると、取付フランジと前部フランジと前部結合部とのスポット溶接結合部と、後部フランジと前部フランジと前部結合部とのスッポト溶接結合部をトンネル部の後端に配列することができる。
【００２３】
請求項６の発明は、請求項５の車体フロア構造において、上記重合する後部フランジと、前部フランジと、前部結合部を上記複数の取付フランジより車幅方向外方においてスポット溶接結合したことを特徴とする。
【００２４】
請求項６の発明によると、後部フランジと、前部フランジと、前部結合部との結合部を取付フランジの車幅方向外方にも配置することによって更に結合剛性を向上させることができる。
【００２５】
請求項７に記載の発明は、請求項２〜６に記載の車体フレーム構造において、上記トンネル部の頂部とトンネルリンフォースとクロスメンバのトンネル結合部とのスポット溶接結合は、上記トンネル部に形成されたトンネルリンフォース結合部と、上記トンネルリンフォースの後端に形成された後方フランジと、上記トンネル結合部先端に形成された前端フランジとを重合せしめ、該重合するトンネルリンフォース結合部と後方フランジと、前端フランジとをスポット溶接結合したことを特徴とする上記トンネル部の頂部とトンネルリンフォースとクロスメンバのトンネル結合部とのスポット溶接結合は、上記トンネル部に形成されたトンネルリンフォース結合部と、上記トンネルリンフォースの後端に形成された後方フランジと、上記トンネル結合部先端に形成された前端フランジとを重合せしめ、該重合するトンネルリンフォース結合部と後方フランジと、前端フランジとをスポット溶接結合したことを特徴とする。
【００２６】
請求項７に記載の発明によると、トンネルリンフォース結合部と、後方フランジと、前端フランジとをスポット溶接結合することによってトンネル部とトンネルリンフォースとクロスメンバが容易かつ確実に結合される。
【００２７】
請求項８に記載の発明は、請求項７の車体フロア構造において、上記トンネル部に形成される後端フランジより車体前方にトンネルリンフォース結合部が形成されることを特徴とする。
【００２８】
請求項８の発明によると、トンネル部に形成される後端フランジよりトンネルリンフォース結合部を前方に配置することによって、トンネルブの後端フランジ部に結合されるリヤフロアパネルの前方フランジの前部フランジ、フロアリンフォースの取付フランジ、クロスメンバの前部結合部とのスポット溶接結合部と、トンネル部のトンネルリンフォース結合部に結合されるトンネルリンフォースの後端部と、クロスメンバのトンネル結合部の前端フランジとのスポット溶接結合部との間が車体前後方向に離間することからフロアの剛性が確保する。
【００２９】
請求項９に記載の車体フロア構造の製造方法は、車体前後方向に延在するトンネル部が形成されたフロントフロアパネルの後部に、リヤフロア面の前部に段差部が形成されたリヤフロアパネルの前部を結合すると共に、上記段差部下部とリヤフロア面との間にクロスメンバを架設して車体幅方向に延在する閉断面形状を形成する車体フロア構造の製造方法において、フロントフロア面の中央部に車体前後方向に延在するトンネル部を有し、トンネル部の後端に後部フランジが形成され、該後方フランジの前方にトンネルリンフォース結合部が形成されたフロントフロアパネルと、上記トンネル部の頂部下面に沿って前後方向に配設されて後端に上記トンネルリンフォース結合部に重合可能な後方フランジが形成されたトンネルリンフォースと、リヤフロア面の前部に段差部が形成されると共に、該段差部の下端に上記フロントフロアパネルに形成された後部フランジに重合可能な前部フランジが形成されたリヤフロアパネルと、該リヤフロアパネルの段差部と結合して車体幅方向に延在する上縁及び下縁に形成されたフランジを有し、上記段差部と協働して車体幅方向に延在する第１閉断面形状を形成するとともに、該下縁に上記トンネル部の後部フランジ及びリヤフロアパネルの前部フランジに重合可能な取付フランジが形成されたフロアリンフォースと、上記段差部とリヤフロア面との間に架設されて上記フロアリンフォースを収容して車体幅方向に延在する第２閉断面形状を形成すると共に、上記トンネル部の頂部下面に沿って車体前方に延設されたトンネル結合部を有し、該トンネル結合部に上記トンネル部に形成した後部フランジ及びリヤフロアパネルに形成された前部フランジに重合可能な上部結合部及び上記トンネルリンフォースに形成された後方フランジに重合可能な前端フランジを有するクロスメンバとを備え、上記フロントフロアパネルのトンネルリンフォース結合部に、上記トンネルリンフォースの後方フランジをスポット溶接結合してフロントフロアパネルとトンネルリンフォースが一体に結合されたフロントフロア部を形成する一方、上記リヤフロアパネルの前部フランジと、フロアリンフォースの取り付けフランジと、クロスメンバの前部結合部とを重合して共にスポット溶接結合してリヤフロントパネルとフロアリンフォースとクロスメンバが一体に結合されたリヤフロア部を形成し、フロントフロアのトンネル部に形成されたトンネルリンフォース結合部とトンネルリンフォースの後方フランジとクロスメンバに形成されたトンネル結合部の前端フランジを重合して共にスポット溶接結合すると共に、フロントフロアパネルの後部フランジとリヤフロアパネルの前部フランジとクロスメンバの前部結合部とを重合して共にスポット溶接結合して上記フロントフロア部と上記リヤフロア部とを連結したことを特徴とする。
【００３０】
請求項９の発明によると、各スッポット溶接結合部において重合されるける結合部材が３枚以内であり、スポット溶接時の加圧力及び電流密度が充分に確保されて安定した結合強度が得られ共に、車体幅方向及び車体前後方向の剛性が確保できる車体構造が得られる。
【００３１】
【発明の実施の形態】
以下、本発明による車体フロア構造及び車体フロア構造の製造方法の実施の形態を、図１乃至図６によって説明する。なお図中矢印Ｆは車体前方を示し、二点鎖線ＣＬは車体幅方向の中心を前後方向に延びる基準線である。
【００３２】
図１は本実施の形態の概要を示す分解斜視図、図２は各部材を結合した状態における図１のＡ−Ａ線断面図、図３は各部材を結合した状態における図１のＢ部拡大斜視図であり、図４は図３のＣ−Ｃ線断面図、図５は図３のＤ−Ｄ線断面図、図６は図３のＥ−Ｅ線断面図である。
【００３３】
車体フロア１は、フロントフロアパネル１０、リヤフロアパネル２０、フロアリンフォース３０、トンネルリンフォース４０及びクロスメンバ５０を主要部材としている。
【００３４】
フロントフロアパネル１０は、図１に示すようにフロントフロア面１１と、車体幅方向の略中央部においてフロントフロア面１１から断面略逆Ｕ字状に隆起して車体前後方向に延在するトンネル部１２とを有している。
【００３５】
フロントフロアパネル１０の後端縁に沿って、段差を介して高段となる後部フランジ１３が延設され、後部フランジ１３にはトンネル部１２の頂部において基準線ＣＬに対して左右対象位置に段差を介して略フロアリンフォース３０の板厚相当分高段となる第２後部フランジ１４が形成され、フロントフロア面１１に対応する部位にはクロスメンバ５０の板厚相当分高段となる第３後部フランジ１５が形成されている。
【００３６】
更に、トンネル部１２の頂部下面には、後部フランジ１３の前縁に沿って上記段差を隔ててトンネルリンフォース結合部１６が形成され、かつフロントフロア面１１の外側縁に沿って延在する側部フランジ１９が折曲形成されている。
【００３７】
リヤフロアパネル２０は、前部に後部シートを搭載するリヤフロア面２１を有し、このリヤフロア面２１は下方に燃料タンク等を配置するためフロントフロアパネル１０のフロントフロア面１１より高く設定され、リヤフロア面２１の前縁に沿って段差部２２が折曲形成されている。
【００３８】
段差部２２の下縁は、上記トンネル１２に対応して凹状に湾曲すると共に、下縁に沿って前方に折曲形成され、かつ上記フロントフロアパネル１０に形成された後部フランジ１３、第２後部フランジ１４及び第３後部フランジ１５に下方から重合可能な前部フランジ２３が形成されている。
【００３９】
更に、リヤフロアパネル２０の外側縁には、リヤフロア面２１及び段差部２２の各外側縁に沿って各々側部フランジ２９が折曲形成されている。
【００４０】
フロアリンフォース３０は、上面３１、後面３２及び下面３３を有する前方側が開放された断面略コ字状であって、上面３１の前端縁に沿って上方に折曲形成されてリヤフロアパネル２０の段差部２２に重合可能な上方フランジ３５及び、下面３３の前端縁に沿って下方に折曲形成されてリヤフロアパネル２０の段差部２２に重合可能な下方フランジ３６が形成されている。
【００４１】
フロアリンフォース３０の上面３１、後面３２及び下面３３の側端に連続形成されて車体側部部材、例えばサイドシル（図示せず）に重合可能な側方フランジ３９が形成され、側部フランジ３９の端部は各々上方フランジ３５及び下方フランジ３６に連続形成されている。
【００４２】
更に、フロアリンフォース３０の下面３３端縁には、上記フロントフロアパネル１０の後端に形成された各々の第２後部フランジ１４に対応する一対の取付フランジ３８が延設されている。取付フランジ３８は略舌片状であってリヤフロアパネル２０の段差部２２の下縁に形成された前部フランジ２３の下面に重合可能に形成されている。
【００４３】
トンネルリンフォース４０は、フロントフロアパネル１０に形成されたトンネル部１２の頂部下面形状に倣った形状で、その後端縁に沿って上記トンネル１２に形成したトンネルリンフォース結合部１６に重合可能な後方フランジ４１が形成されている。
【００４４】
クロスメンバ５０は、後面５１と、該後面５１の下端から前方に延設された下面５２からなる断面略Ｌ字状に形成されて車体幅方向に延在し、この下面５２は両側端方向に移行するに従って下降するように緩やかに湾曲形成されている。
【００４５】
下面５２の前縁中央部にトンネル部１２の頂部下面に重合可能なトンネル結合部５３が延設され、トンネル結合部５３の前端縁に沿って上記トンネルリンフォース４０の後方フランジ４１に下方から重合可能な前端フランジ５４が形成され、前端フランジ５４の後縁に沿って上記段差部２２の下縁に形成された前部フランジ２３の下面に対向する前部結合部５５が形成されている。
【００４６】
更にトンネル結合部５３の両側縁から下面５２の前縁に亘って連続してリヤフロアパネル２０の段差部２２に重合可能な下部フランジ５６が形成され、かつ下面５２の前縁の端部近傍には、上記フロントフロア面１１の後縁に形成した上記第３後部フランジ１５の下面に重合可能な舌片状の結合フランジ５７が突設されている。
【００４７】
一方、後面５１の上縁は、リヤフロアパネル２０のリヤフロア面２１の下面に倣った形状で、その上縁に沿ってリヤフロア面２１の下面に重合可能な上部フランジ５８が折曲形成されている。
【００４８】
また、クロスメンバ５０の後面５１及び下面５２の各外側縁に沿って側部フランジ５９が折曲形成されている。
【００４９】
なお、図２において符号６０は、リヤシート（図示せず）をボルト６１によってリヤフロア面２１に取付支持するためのシート取付用リンフォースである。
【００５０】
次に、このように形成されたフロントフロアパネル１０、リヤフロアパネル２０、フロアリンフォース３０、トンネルリンフォース４０及びクロスメンバ５０等の結合について説明する。なお、×印はフロントフロアパネル１０トンネルフォース４０からなるフロンとフロア部ＦＦとリヤフロアパネル２０、フロアリンフォース３０及びクロスメンバ５０等からなるリヤフロア部ＲＦとの結合時におけるスッポット溶接部を示し、○印は予めフロントフロアパネル１０とトンネルリンフォース４０を結合するスポット溶接結合部及びリヤフロアパネル２０、フロアリンフォース３０及びクロスメンバ５０を結合するスポット溶接部を示している。
【００５１】
先ず、図３に示すようにフロントフロアパネル１０に形成された前後方向に延在するトンネル部１２の頂部下面に、下方よりトンネルリンフォース４０を重合すると共に、図５にスポット溶接部を○印で示すように、互いに重合したトンネル部１２に形成したトンネルリンフォース結合部１６とトンネルリンフォース４０の後方フランジ４１をスポット溶接結合してフロントフロアパネル１０とトンネルリンフォース４０とを一体に結合してフロントフロア部ＦＦを形成する。
【００５２】
一方、予めフロアリンフォース３０にシート取付用リンフォース６０を取り付け、かつフロアリンフォース３０の下面３３に突設された取付フランジ３８をリヤフロアパネル２０の段差部２２下縁に形成された前部フランジ２３の下面に重合すると共に、リヤフロアパネル２０の段差部２２にフロアリンフォース３０の上方フランジ３５及び下方フランジ３６を重合し、かつ段差部２２に上方フランジ３５及び下方フランジ３６をスポット溶接してリヤフロアパネル２０とフロアリンフォース３０を一体結合する。
【００５３】
このリヤフロアパネル２０とフロアリングフォース３０との結合により、段差部２２とフロアリンフォース３０との協働による車幅方向に延在する第１閉断面形状Ａが形成され、段差部２２及びフロアリングフォース３０の形状が拘束されてリヤフロアパネル２０前部の剛性確保、特に車幅方向から作用する荷重に対する剛性が確保される。
【００５４】
次に、図４に示すようにリヤフロアパネル２０の段差部２２のに形成された前部フランジ２３の車幅方向中央部に、フロアリンフォース３０の取付フランジ３８を介在してクロスメンバ５０のトンネル結合部５３に形成された前部結合部５５を下方から重合し、かつ下部フランジ５６をフロアリンフォース３０の下方フランジ３６を介在して前部フランジ２３を段差部２２に重合すると共に、図２に示すように後面５１の上縁に形成された上部フランジ５８をシート取付用リンフォース６０を介在してリヤフロア面２１の下面に重合する。
【００５５】
そして、図４に○印で示すように重合するリヤフロアパネル２０の前部フランジ２３と、フロアリンフォース３０の取付フランジ３８と、クロスメンバ５０のトンネル結合部５３を共にスポット溶接結合する。同様に重合するリヤフロアパネル２０の段差部２２と、フロアリンフォース３０の下方フランジ３６と、クロスメンバ５０のトンネル結合部５３に形成された前部結合部５５を共にスポット溶接結合すると共に、クロスメンバ５０の後面５１の上縁に形成された上部フランジ５０をリヤフロア面２１にスポット溶接して、リヤフロアパネル２０、フロアリンフォース３０及びクロスメンバ５０を一体結合してリヤフロア部ＲＦを形成する。
【００５６】
このようにして形成されたリヤフロア部ＲＦは、リヤフロアパネル２０とフロアリンフォース３０とクロスメンバ５０の結合により、上記リヤフロアパネル２０の段差部２２によって形成される第１閉断面形状Ａに加え更に、フロアリンフォース３０を収容して車体幅方向に延在する第２閉断面形状Ｂが形成され、リヤフロアパネル２０及びクロスメンバ２０の形状が拘束されてリヤフロアパネル５０の前部の剛性がより確保される。
【００５７】
これらのリヤフロア部ＲＦのスポット溶接結合は、各スポット溶接結合部における部材の重合枚数が、各々３枚以内であり、スポット溶接時の加圧力及び電流密度が充分に確保され、均一でかつ充分な結合強度が得られる。
【００５８】
次に、このように形成されたフロントフロア部ＦＦの後部と、リヤフロア部ＲＦの前部との結合について説明する。
【００５９】
フロントフロアパネル１０に形成されたトンネル部１２の頂部後端に形成された第２後部フランジ１４とフロアリンフォース３０に突設形成された取付フランジ３８とが対応する状態で、フロントフロアパネル１０の後部フランジ１３の下面に下方よりリヤフロアパネル２０の前部フランジ２３を重合すると共に、トンネル１２にスポット溶接結合されたトンネルリンフォース４０の後方フランジ４１の下面に下方よりクロスメンバ５０のトンネル結合部５３に形成された前端フランジ５４を重合する。
【００６０】
そして、図５に×印で示すようにトンネル１２の頂部後端縁に形成された第２後部フランジ１４間において重合するフロンフロアパネル１０の後部フランジ１３と、リヤフロアパネル２０の前部フランジ２３と、クロスメンバ５０のトンネル結合部５３に形成された前部結合部５５とを共にスポット溶接結合する。
【００６１】
同様に、図６に×印を示すようにトンネル部１２の頂部後端の側端近傍位置、換言するとフロアリンフォース３０に形成された結合フランジ３８より外方において結合フランジ３８が介在しない位置において、互いに重合する後部フランジ１３のトンネル部１２の頂部両端近傍と、リヤフロアパネル２０の前部フランジ２３と、トンネル結合部５３に形成された前部結合部５５の両端近傍とを共にスポット溶接結合する。
【００６２】
更に、図４に×印で示すように、重合するトンネル部１２に形成されたトンネルリンフォース結合部１６と、トンネル１２にスポット溶接結合されたトンネルリンフォース４０の後方フランジ４１と、クロスメンバ５０のトンネル結合部５３に形成された前端フランジ５４とを共にスポット溶接結合する。
【００６３】
従って、トンネル１２の頂部後端部周辺においてフロントフロアパネル１０に形成されたトンネル１２の後端部、リヤフロアパネル２０に形成された段差部２２の中央部、フロアリンフォース３０に形成された下面３３の中央部、トンネルリンフォース４０の後端部及びクロスメンバ５０の下面５２に突設されたトンネル結合部５３が互いに結合され、しかも各スポット溶接結合における部材の重合枚数が、各々３枚以内でありスポット溶接時の加圧力及び電流密度が充分に確保されて安定した結合強度が得られる。
【００６４】
また、フロントフロアパネル１０のフロントフロア面１１の後縁１２おいても重合するフロントフロア面１１の後縁に形成された後部フランジ１３と、リヤフロアパネル２０の段差部２２の下縁に折曲形成された前部フランジ２３をスポット溶接結合し、同様に互いに重合する後部フランジ１３に連続形成された第３後部フランジ１５と、第３フランジ１５に対応する前部フランジ２３の部分と、クロスメンバ５０に形成された結合フランジ５７とをスポット溶接結合する。
【００６５】
このようにしてフロントフロア部ＦＦとリヤフロア部ＦＲとが強固に結合されたフロアＦＬは、その前端、即ちフロントフロアパネル１０及びトンネルリンフォース４０の前端がエンジンルームと車室とを区画するトーボード（図示せず）の下端が結合される。
【００６６】
フロアＦＬの側縁にはサイドシルインナとサイドシルアウタによって車体前後方向に延在する閉断面形状のサイドシル（図示せず）が結合される。詳細に説明すると、フロントフロアパネル１０、リヤフロアパネル２０、フロアリンフォース３０及びクロスメンバ５０の各外側縁に折曲形成された各側部フランジ１９、２９、３９、５９がサイドシルのサイドシルインナに重合してスポット溶接結合される。
【００６７】
更に、フロントフロアパネル１０のフロントフロア面１１上にはサイドシとトンネル１２との間に架設されフロントシートを支持するシート支持クロスメンバ（図示せず）を配設する。
【００６８】
このように構成された本実施の形態による車体フロア構造によると、リヤフロアパネル２０とフロアリングフォース３０との協働により車体幅方向に延在する閉断面形状Ａが形成され、更に該閉断面形状Ａを収容するようにリヤフロアパネル２０とクロスメンバ５０によって閉断面形状Ｂが形成される。換言すると車体幅方向に二重の閉断面形状Ａ及びＢが形成されてフロア１の車体幅方向の形状が拘束されて車体側方から作用する衝撃荷重を効率よく他の車体部在に分散伝達して車体フロア１、ひいては車室の変形が防止された安全性が向上する。
【００６９】
また、フロントフロア１０のトンネル部１２が前後方向に亘ってトンネルリンフォース４０によって補剛され、かつトンネル部１２及びトンネルリンフォース４０がフロアリンフォース３０に延設されたトンネル結合部５３と結合してフロントフロア部ＦＦとリヤフロア部ＦＲが強固に結合されてフロア１の前後方向の剛性が確保されてフロア１の変形が防止され、その結果車体前後方向からの衝撃荷重が作用した際、衝撃荷重がフロア１を介して効率的に他の車体部在に分散伝達されて安全性が向上する。
【００７０】
以上説明では、フロントフロア１０のトンネル部１２に沿ってリヤフロア部ＲＦから突出するトンネル結合部５３をクロスメンバ５０に形成したがリヤフロアパネル２０、フロアリンフォースメンバ３０等に適宜形成する等本発明は、上記実施の形態に限定されることなく発明の趣旨を逸脱しない範囲で種々変更可能である。
【００７１】
【発明の効果】
以上説明した本発明の車体フロア構造及び車体フロア構造の製造方法によると、リヤフロアパネルとフロアリンフォースとの協働及びリヤフロアパネルとクロスメンバによって各々閉断面形状が形成されてフロアの車体側方から作用する衝撃荷重による変形が抑制されて車室の変形が防止された安全性が向上すると共に、フロントフロアのトンネル部が前後方向に亘ってトンネルリンフォースによって補剛され、かつトンネル部及びトンネルリンフォースがリヤフロア部から延設されたトンネル結合部と結合してフロントフロア部とリヤフロア部が強固に結合されてフロアの前後方向の剛性が確保され、フロアの変形が防止されて車体前後方向からの衝撃荷重が作用した際、衝撃荷重がフロアを介して効率的に他の車体部在に分散伝達されて安全性が向上する等車両の安全性に向上に貢献すること大なるものである。
【図面の簡単な説明】
【図１】本発明における車体フロア構造及び車体フロア構造の製造方法の実施に形態の概要を示す分解斜視図である。
【図２】各部材を結合した状態における図１のＡ−Ａ線断面図である。
【図３】各部材を結合した状態における図１のＢ部拡大斜視図である。
【図４】図３におけるＣ−Ｃ線断面図である。
【図５】図３におけるＤ−Ｄ線断面図である。
【図６】図３におけるＥ−Ｅ線断面図である。
【図７】従来の車体フロア構造の概要を示す斜視図である。
【図８】従来の車体フロア構造の概要を示す斜視図である。
【符号の説明】
１車体フロア
１０フロントフロアパネル
１１フロントフロア面
１２トンネル部
１３後部フランジ
１６トンネルリンフォース結合部
２０リヤフロアパネル
２１リヤフロア面
２２段差部
２３前部フランジ
３０フロアリンフォース
３１上面
３２後面
３３下面
３８取付フランジ
４０トンネルリンフォース
４１後方フランジ
５０クロスメンバ
５１後面
５２下面
５３トンネル結合部
５４前端フランジ
５５前部結合部
ＦＦフロントフロア部
ＲＦリヤフロア部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle body floor structure and a method for manufacturing the vehicle body floor structure, and more particularly to a vehicle body floor structure for coupling a front floor panel and a rear floor panel of a vehicle body and a method for manufacturing the vehicle body floor structure.
[0002]
[Prior art]
Since the fuel tank is generally disposed below the floor of the vehicle body, there is a type in which the rear floor panel, which is the rear half of the floor, is connected with a step higher than the front floor panel, which is the front half. In this case, usually, a cross member is coupled to the back side of the stepped portion formed on the rear floor panel to form a closed cross section extending in the vehicle width direction by the stepped portion and the crossmember to improve rigidity.
[0003]
On the other hand, in order to further improve the rigidity of the floor, the rear edge 103 of the tunnel portion 102 of the front floor panel 101 is disposed in the vehicle width direction as disclosed in Japanese Utility Model Laid-Open No. 1-68991 and shown in a perspective view in FIG. The rib 107 formed on the stepped portion 106 of the rear floor panel 105 is formed so as to be superposed on the rear end edge 103, and the rear end is formed. A vehicle that improves the lateral rigidity of the floor 100 by spot-welding the rear end edge 103, the rib 107, and the flange 109 together with the flange 109 of the cross member 108 sandwiched between the edge 103 and the rib 107. A floor structure has been proposed.
[0004]
Further, as disclosed in Japanese Utility Model Laid-Open No. 2-56787 and shown in a perspective view in FIG. 8, a rear floor panel 115 is coupled to a rear end portion of a front floor panel 111 having a tunnel portion 102 and a rear floor panel 111. In the vehicle body floor structure including the cross member 107 that forms a closed cross section extending in the vehicle body width direction in cooperation with the vehicle body, a reinforcing portion that extends forward from the cross member 107 along the lower surface of the tunnel portion 102. A vehicle body floor structure has been proposed in which 108 is extended and a closed cross section is formed by the lower surface of the tunnel 102 and the reinforcing portion 108 to ensure the coupling strength between the front floor panel 111 and the rear floor panel 115.
[0005]
[Problems to be solved by the invention]
According to the vehicle floor structure disclosed in Japanese Utility Model Laid-Open No. 1-68991 above, the rear end edge of the tunnel portion of the front floor panel, the rib formed on the rear floor panel, and the flange of the cross member are spot welded together. By doing so, the shape of the rear floor panel is constrained to improve the rigidity of the floor in the vehicle body width direction.
[0006]
However, although the rear floor panel and the cross member form a closed cross-sectional shape extending in the vehicle width direction, when an excessive impact load is applied from the side of the vehicle body, the load that acts on the rear floor panel and the cross member via the side sill The rear floor panel and cross member are deformed by this, and the impact load is prevented from being efficiently distributed and transmitted to the opposite side sill and other vehicle body members via the rear floor and cross member. There is a concern that the side body member may enter the vehicle interior.
[0007]
Also, spot welding is performed by superimposing the rear edge of the front floor panel where the front floor panel and rear floor panel are connected in the vehicle body width direction, the rib formed on the stepped portion of the rear floor panel, and the flange of the cross member. Because of the coupling, if an excessive impact load is applied from the front and rear of the vehicle body, for example from the front, the impact load that cannot be absorbed by the front of the vehicle body is applied from the front to the front of the front floor panel via the toe board. In addition, the stress concentrates on the joint between the front floor panel and the rear floor panel, and the part buckles and deforms, so that the load is not efficiently transmitted to the side sill and other body members that are connected to the floor. There is a concern that it will be deformed.
[0008]
Further, according to the vehicle floor structure of Japanese Utility Model Laid-Open No. 2-56787, the rear floor panel and the cross member form a closed cross section extending in the vehicle width direction to restrain the shape of the rear floor panel, and the front floor panel and the rear floor panel are The strength of the coupling between the front floor panel and the rear floor panel is improved by being joined by a reinforcing portion formed on the cross member.
[0009]
However, as in the case of the car floor of Japanese Utility Model Laid-Open No. 1-68991, the rear floor panel and the cross member form a closed cross-sectional shape extending in the car body width direction, but when an excessive impact load is applied from the car body side. The floor is deformed by the load acting on the rear floor panel and the cross member via the side sill, and the front floor is deformed by the excessive impact load from the longitudinal direction of the vehicle body. As a result, the impact load is efficiently distributed to other vehicle body members. There is a concern that the transmission is hindered and the side body member enters the vehicle compartment.
[0010]
On the other hand, it is desired to further improve the rigidity of the vehicle body floor in order to prevent the deformation of the vehicle body floor and reduce the influence on the interior by efficiently distributing and transmitting the impact load from the side of the vehicle body and the vehicle body longitudinal direction.
[0011]
Accordingly, an object of the present invention made in view of such a point is to provide a vehicle body floor structure that can sufficiently prevent the deformation of the vehicle body floor and ensure safety when an impact load is applied to the vehicle body from the side of the vehicle body and from the longitudinal direction of the vehicle body. And it is providing the manufacturing method of a vehicle body floor structure.
[0012]
[Means for Solving the Problems]
The vehicle body floor structure according to claim 1, which achieves the above object, includes a rear floor panel in which a step portion is formed in a front portion of a rear floor surface at a rear portion of a front floor panel in which a tunnel portion extending in a longitudinal direction of the vehicle body is formed. In the vehicle body floor structure in which a cross member is installed between the lower end of the stepped portion and the rear floor surface to form a closed cross-sectional shape extending in the vehicle body width direction, the center portion of the front floor surface is connected. A front floor panel in which a tunnel portion extending in the longitudinal direction of the vehicle body is formed, a tunnel reinforcement disposed in the longitudinal direction of the vehicle body along the top lower surface of the tunnel portion, and a step portion is formed in the front portion of the rear floor surface. A rear floor panel in which a lower end of the step portion is coupled to a rear portion of the front floor including the tunnel portion; and a step portion of the rear floor panel; It has a flange formed on the upper edge and the lower edge that are joined and extend in the vehicle body width direction, and forms a first closed cross-sectional shape extending in the vehicle body width direction in cooperation with the step portion and Edge joins to the tunnel part A floor reinforcement, a cross member that is spanned between the step portion and the rear floor surface, accommodates the floor reinforcement and forms a second closed cross-sectional shape extending in the vehicle body width direction, and a lower portion of the rear floor step portion And at least one of the floor reinforcement and the cross member is provided with a tunnel coupling portion that extends forward of the vehicle body along the bottom lower surface of the tunnel portion and is coupled to the tunnel portion and the tunnel reinforcement. To do.
[0013]
According to the first aspect of the present invention, the first closed cross-sectional shape extending in the vehicle body width direction is formed by the cooperation of the rear floor panel and the floor reinforcement, and the first closing is performed by the cooperation of the rear floor panel and the cross member. Since the second closed cross-sectional shape extending in the vehicle body width direction is accommodated by accommodating the cross-sectional shape, the shape of the floor in the vehicle body width direction is constrained, and the floor is deformed against an impact load acting from the vehicle body side direction. The impact load can be efficiently distributed and transmitted to other vehicle body members.
[0014]
On the other hand, the tunnel portion of the front floor panel that forms the front floor is stiffened by the tunnel reinforcement, and the tunnel portion is formed on at least one of the rear floor, the floor reinforcement, and the cross member that forms the rear floor portion on the tunnel portion and the tunnel reinforcement. The front and rear rigidity of the front floor is secured because the tunnel joint extending along the front and rear is secured, and the rigidity of the front floor and the rear floor is secured. The deformation of the floor is suppressed with respect to the impact load that is restrained and acts from the longitudinal direction of the vehicle body, and the impact load can be efficiently distributed and transmitted to other vehicle body members.
[0015]
The invention of the vehicle body floor structure according to claim 2 that achieves the above object is characterized in that a step portion is formed at the front portion of the rear floor surface at the rear portion of the front floor panel in which the tunnel portion extending in the vehicle longitudinal direction is formed. In the vehicle body floor structure that joins the front portion of the rear floor panel and lays a cross member between the lower end of the stepped portion and the rear floor surface to form a closed cross-sectional shape extending in the vehicle width direction, the center of the front floor surface A front floor panel formed with a tunnel portion extending in the longitudinal direction of the vehicle body, a tunnel reinforcement disposed in the longitudinal direction of the vehicle body along the top lower surface of the tunnel portion, and a step portion at the front portion of the rear floor surface A rear floor panel formed with a stepped portion of the rear floor panel; It has a flange formed on the upper edge and the lower edge that are joined and extend in the vehicle body width direction, and forms a first closed cross-sectional shape extending in the vehicle body width direction in cooperation with the step portion and Edge joins to the tunnel part A floor reinforcement is formed between the stepped portion and the rear floor surface to form the second closed cross-sectional shape that accommodates the floor reinforcement and extends in the vehicle body width direction, and is formed on the top lower surface of the tunnel portion. And a cross member having a tunnel coupling portion extending forward of the vehicle body along the vehicle body. The lower portion of the stepped portion of the rear floor panel, the floor reinforcement and the cross member are spot welded together, and the top of the tunnel portion and the tunnel ring The force and the tunnel joint portion of the cross member are spot welded together, and the top portion of the tunnel portion, the stepped portion lower portion of the rear floor panel, and the cross member are spot welded together.
[0016]
The invention of claim 2 further comprises the invention of claim 1. Body In addition to the effect of claim 1, the lower edge of the stepped portion of the rear floor panel, the floor reinforcement and the cross member are spot welded together, and the top of the tunnel portion, the tunnel reinforcement and the tunnel joint portion of the cross member Are joined together by spot welding, and the top part of the tunnel part, the lower edge of the step part of the rear floor panel and the cross member are joined together by spot welding, and the constituent members are joined together. Sport Polymerized at the weld joint Ru The number of combined members is three or less, and a sufficient bonding force and current density at the time of spot welding are ensured, and a stable bonding strength can be obtained.
[0017]
According to a third aspect of the present invention, in the vehicle body floor structure according to the second aspect, spot welding connection between the lower edge of the stepped portion of the rear floor panel, the floor reinforcement, and the cross member is provided at the edge of the floor reinforcement force. A mounting flange projecting so as to be superposed on a portion corresponding to the top of the portion, a front flange formed at a lower portion of the step portion of the rear floor panel, and a front coupling portion formed at a tunnel coupling portion of the cross member And the mounting flange, the front flange, and the front joint portion to be superposed are spot welded together.
[0018]
According to the third aspect of the present invention, the rear floor panel can be easily assembled by spot welding the mounting flange, the front flange, and the front coupling portion respectively formed on the lower edge of the stepped portion of the rear floor panel, the floor reinforcement, and the cross member. The lower edge of the stepped portion of the panel, the floor reinforcement, and the cross member are easily and reliably coupled.
[0019]
According to a fourth aspect of the present invention, in the vehicle body floor structure of the second or third aspect, the spot welded connection between the top of the tunnel portion, the lower edge of the stepped portion of the rear floor panel, and the cross member is formed in the tunnel portion. A rear end flange, a front flange formed at the lower edge of the stepped portion of the rear floor panel, and a front joint formed at the tunnel joint of the cross member are overlapped, and the rear flange to be overlapped, The part flange and the front joint part are spot welded together.
[0020]
According to the invention of claim 4, the rear end flange formed in the tunnel portion, the front flange formed in the rear floor panel, and the front joint portion formed in the tunnel joint portion of the cross member are welded. Thus, the top portion of the tunnel portion, the lower edge of the stepped portion of the rear floor panel, and the cross member are easily and reliably coupled.
[0021]
According to a fifth aspect of the present invention, in the vehicle body floor structure of the second or third aspect, the spot welded connection between the lower edge of the stepped portion of the rear floor panel, the floor reinforcement, and the cross member is at the edge of the floor reinforcement force. A plurality of mounting flanges projecting apart from each other so as to overlap each other at a portion corresponding to the top of the tunnel portion; a front flange formed at a lower edge of the step portion of the rear floor panel; and a tunnel coupling portion of the cross member And the front mounting portion, the front flange, and the front connecting portion to be spot welded together, and the top portion of the tunnel portion, the lower edge of the stepped portion of the rear floor panel, and the cross member. Spot welded joints are formed on the rear flange formed in the tunnel portion and the lower edge of the stepped portion of the rear floor panel. The front flange and the front joint formed at the tunnel joint of the cross member are overlapped, and the overlapping rear flange, front flange, and front joint are connected between the plurality of mounting flanges. It is characterized by spot welding connection at the non-overlapping part.
[0022]
According to the invention of claim 5, the spot welded joint portion of the mounting flange, the front flange and the front joint portion, and the spot weld joint portion of the rear flange, the front flange and the front joint portion are connected to the rear end of the tunnel portion. Can be arranged.
[0023]
According to a sixth aspect of the present invention, in the vehicle body floor structure of the fifth aspect, the overlapping rear flange, the front flange, and the front coupling portion are spot-welded to the outside in the vehicle width direction from the plurality of mounting flanges. It is characterized by.
[0024]
According to the sixth aspect of the present invention, it is possible to further improve the coupling rigidity by arranging the coupling portion of the rear flange, the front flange, and the front coupling portion also on the outer side in the vehicle width direction of the mounting flange.
[0025]
According to a seventh aspect of the present invention, in the vehicle body frame structure according to the second to sixth aspects, a spot welded connection between the top of the tunnel portion, the tunnel reinforcement and the tunnel joint portion of the cross member is formed in the tunnel portion. The tunnel reinforcement joint portion formed, the rear flange formed at the rear end of the tunnel reinforcement, and the front end flange formed at the front end of the tunnel joint portion are superposed, and the tunnel reinforcement joint portion to be superposed and the rear The spot welded connection between the top of the tunnel part, the tunnel reinforcement, and the tunnel joint of the cross member is characterized in that the flange and the front end flange are spot welded. A rear flange formed at the rear end of the tunnel reinforcement, and the ton By polymerizing a front flange formed on Le coupling tip, and wherein and the rear flange tunnel reinforcement binding unit for the polymerization, that the front flange and spot welded together.
[0026]
According to the seventh aspect of the present invention, the tunnel portion, the tunnel reinforcement, and the cross member are easily and reliably connected by spot welding the tunnel reinforcement connecting portion, the rear flange, and the front end flange.
[0027]
According to an eighth aspect of the present invention, in the vehicle body floor structure of the seventh aspect, a tunnel reinforcement coupling portion is formed in front of the vehicle body from a rear end flange formed in the tunnel portion.
[0028]
According to the invention of claim 8, the front flange of the front flange of the rear floor panel which is coupled to the rear end flange portion of the tunnel bracket by disposing the tunnel reinforcement joint portion in front of the rear end flange formed in the tunnel portion. , A floor reinforcement mounting flange, a spot weld joint with the front joint of the cross member, a rear end of the tunnel reinforcement coupled to the tunnel reinforcement joint of the tunnel, and a tunnel joint of the cross member Since the space between the front end flange and the spot welded joint is separated in the longitudinal direction of the vehicle body, the rigidity of the floor is secured.
[0029]
The method for manufacturing a vehicle body floor structure according to claim 9 includes: a front floor panel having a tunnel portion extending in the longitudinal direction of the vehicle body; and a front portion of the rear floor panel having a step portion formed at a front portion of the rear floor surface. In the manufacturing method of a vehicle body floor structure, in which a cross member is installed between the lower part of the step and the rear floor surface to form a closed cross-sectional shape extending in the vehicle body width direction, A front floor panel having a tunnel portion extending in the longitudinal direction of the vehicle body, a rear flange formed at the rear end of the tunnel portion, and a tunnel reinforcement joint portion formed in front of the rear flange, A tunnel reinforcement disposed in the front-rear direction along the bottom surface of the top portion and having a rear flange capable of being superposed on the tunnel reinforcement joint at the rear end; A rear floor panel in which a step portion is formed at the front portion of the rear floor surface and a front flange that can be overlapped with a rear flange formed at the front floor panel is formed at the lower end of the step portion, and the step of the rear floor panel Department and A flange formed on the upper edge and the lower edge that extends in the vehicle body width direction by coupling and forms a first closed cross-sectional shape extending in the vehicle body width direction in cooperation with the stepped portion; On the bottom edge A floor reinforcement having a superimposable mounting flange formed on the rear flange of the tunnel portion and the front flange of the rear floor panel, and a vehicle body that is installed between the step portion and the rear floor surface and accommodates the floor reinforcement. A second closed cross-sectional shape extending in the width direction is formed, and a tunnel coupling portion extending forward of the vehicle body is formed along the lower surface of the top portion of the tunnel portion, and the tunnel coupling portion is formed in the tunnel portion. A tunnel of the front floor panel, comprising: an upper coupling portion that can be superposed on a rear flange and a front flange formed on the rear floor panel; and a cross member having a front end flange that can be superposed on a rear flange formed on the tunnel reinforcement. The rear flange of the tunnel reinforcement is spot welded to the reinforcement joint, and the flow is A front floor portion in which the front floor panel and the tunnel reinforcement are integrally joined together, while the front flange of the rear floor panel, the mounting flange of the floor reinforcement, and the front joint portion of the cross member are superposed. Spot welded together to form a rear floor part in which the rear front panel, floor reinforcement and cross member are joined together, a tunnel reinforcement joint formed in the tunnel part of the front floor and a rear flange of the tunnel reinforcement The front flange of the tunnel joint formed on the cross member is overlapped and spot welded together, and the rear flange of the front floor panel, the front flange of the rear floor panel, and the front joint of the cross member are overlapped together. Spot welded joint and above front floor part Characterized in that connecting the rear floor portion.
[0030]
According to the ninth aspect of the present invention, there are no more than three coupling members that can be polymerized in each spot welding joint, and sufficient pressure and current density at the time of spot welding can be ensured to obtain a stable coupling strength. Thus, a vehicle body structure that can ensure rigidity in the vehicle body width direction and the vehicle body longitudinal direction can be obtained.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a vehicle body floor structure and a vehicle body floor structure manufacturing method according to the present invention will be described below with reference to FIGS. In the figure, an arrow F indicates the front of the vehicle body, and a two-dot chain line CL is a reference line extending in the front-rear direction at the center in the vehicle width direction.
[0032]
1 is an exploded perspective view showing an outline of the present embodiment, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1 in a state in which the respective members are joined, and FIG. 3 is a portion B in FIG. 4 is an enlarged perspective view, FIG. 4 is a cross-sectional view taken along line CC in FIG. 3, FIG. 5 is a cross-sectional view taken along line DD in FIG. 3, and FIG.
[0033]
The vehicle body floor 1 includes a front floor panel 10, a rear floor panel 20, a floor reinforcement 30, a tunnel reinforcement 40, and a cross member 50 as main members.
[0034]
As shown in FIG. 1, the front floor panel 10 includes a front floor surface 11 and a tunnel portion that protrudes from the front floor surface 11 in a substantially inverted U shape in the vehicle width direction and extends in the vehicle longitudinal direction. 12.
[0035]
A rear flange 13 that becomes a high step is extended along the rear end edge of the front floor panel 10 through a step, and the rear flange 13 has a step at the left and right target positions at the top of the tunnel portion 12 with respect to the reference line CL. A second rear flange 14 having a height corresponding to the plate thickness of the floor reinforcement 30 is formed through a third portion, and a third step corresponding to the plate thickness of the cross member 50 is formed in a portion corresponding to the front floor surface 11. A rear flange 15 is formed.
[0036]
Further, a tunnel reinforcement coupling portion 16 is formed on the lower surface of the top portion of the tunnel portion 12 along the front edge of the rear flange 13 with the step difference therebetween, and the side extending along the outer edge of the front floor surface 11. The part flange 19 is bent.
[0037]
The rear floor panel 20 has a rear floor surface 21 on which a rear seat is mounted at the front, and the rear floor surface 21 is set higher than the front floor surface 11 of the front floor panel 10 in order to dispose a fuel tank or the like below. A step portion 22 is bent along the front edge of 21.
[0038]
The lower edge of the stepped portion 22 is curved in a concave shape corresponding to the tunnel 12, is bent forward along the lower edge, and is formed on the front floor panel 10, a rear flange 13, a second rear portion A front flange 23 that can be superposed from below is formed on the flange 14 and the third rear flange 15.
[0039]
Further, side flanges 29 are bent at the outer edge of the rear floor panel 20 along the outer edges of the rear floor surface 21 and the stepped portion 22.
[0040]
The floor reinforcement 30 has a substantially U-shaped cross section with the front side having an upper surface 31, a rear surface 32, and a lower surface 33 open, and is bent upward along the front edge of the upper surface 31 to form a step in the rear floor panel 20. The upper flange 35 that can be overlapped with the portion 22 and the lower floor 33 are bent downward along the front edge of the lower surface 33 so that the rear floor panel 20 Step 22 is formed with a lower flange 36 which can be polymerized.
[0041]
A side flange 39 that is continuously formed on the side edges of the upper surface 31, the rear surface 32, and the lower surface 33 of the floor reinforcement 30 and that can be superposed on a vehicle body side member, for example, a side sill (not shown), is formed. The end portions are formed continuously on the upper flange 35 and the lower flange 36, respectively.
[0042]
Further, a pair of mounting flanges 38 corresponding to the respective second rear flanges 14 formed at the rear end of the front floor panel 10 are extended from the edge of the lower surface 33 of the floor reinforcement 30. The mounting flange 38 is substantially tongue-shaped and is formed on the lower surface of the front flange 23 formed on the lower edge of the stepped portion 22 of the rear floor panel 20 so as to be superposed.
[0043]
The tunnel reinforcement 40 has a shape following the shape of the top bottom surface of the tunnel portion 12 formed on the front floor panel 10 and can be superposed on the tunnel reinforcement joint portion 16 formed on the tunnel 12 along the rear edge. A flange 41 is formed.
[0044]
The cross member 50 is formed in a substantially L-shaped cross section including a rear surface 51 and a lower surface 52 extending forward from the lower end of the rear surface 51, and extends in the vehicle body width direction. It is gently curved so as to descend as it moves.
[0045]
A tunnel coupling portion 53 that can be superposed on the top lower surface of the tunnel portion 12 is extended at the center of the front edge of the lower surface 52, and is superposed on the rear flange 41 of the tunnel reinforcement 40 from below along the front edge of the tunnel coupling portion 53. A possible front end flange 54 is formed, and a front coupling portion 55 is formed along the rear edge of the front end flange 54 so as to face the lower surface of the front flange 23 formed at the lower edge of the stepped portion 22.
[0046]
Further, a lower flange 56 that can overlap the stepped portion 22 of the rear floor panel 20 is formed continuously from both side edges of the tunnel coupling portion 53 to the front edge of the lower surface 52, and in the vicinity of the end portion of the front edge of the lower surface 52. A superposed tongue-like coupling flange 57 projects from the lower surface of the third rear flange 15 formed at the rear edge of the front floor surface 11.
[0047]
On the other hand, the upper edge of the rear surface 51 has a shape that follows the lower surface of the rear floor surface 21 of the rear floor panel 20, and an upper flange 58 that can be superposed on the lower surface of the rear floor surface 21 is bent along the upper edge.
[0048]
Further, side flanges 59 are bent along the outer edges of the rear surface 51 and the lower surface 52 of the cross member 50.
[0049]
In FIG. 2, reference numeral 60 denotes a seat mounting reinforcement for mounting and supporting a rear seat (not shown) to the rear floor surface 21 with bolts 61.
[0050]
Next, the coupling of the front floor panel 10, the rear floor panel 20, the floor reinforcement 30, the tunnel reinforcement 40, the cross member 50, and the like formed as described above will be described. In addition, X mark shows the spot welding part at the time of the coupling | bonding of the front floor panel 10 which consists of the tunnel force 40, the floor part FF, the rear floor panel 20, the floor reinforcement 30, the cross floor 50, etc. The mark indicates a spot weld joint for connecting the front floor panel 10 and the tunnel reinforcement 40 and a spot weld joint for connecting the rear floor panel 20, the floor reinforcement 30 and the cross member 50 in advance.
[0051]
First, as shown in FIG. 3, the tunnel reinforcement 40 is superposed on the lower surface of the top portion of the tunnel portion 12 formed in the front floor panel 10 extending in the front-rear direction, and the spot welded portion is marked with a circle in FIG. As shown in FIG. 1, the front reinforcement panel 16 and the tunnel reinforcement 40 are joined together by spot welding the tunnel reinforcement joint portion 16 formed in the tunnel portion 12 overlapped with each other and the rear flange 41 of the tunnel reinforcement 40. The front floor portion FF is formed.
[0052]
On the other hand, a seat mounting reinforcement 60 is attached to the floor reinforcement 30 in advance, and a mounting flange 38 protruding from the lower surface 33 of the floor reinforcement 30 is formed at the lower edge of the step portion 22 of the rear floor panel 20. And polymerized on the lower surface of 23, Rear floor panel 20 The upper flange 35 and the lower flange 36 of the floor reinforcement 30 are superposed on the stepped portion 22 and the upper flange 35 and the lower flange 36 are spot welded to the stepped portion 22 to integrally couple the rear floor panel 20 and the floor reinforcement 30. .
[0053]
The combination of the rear floor panel 20 and the flooring force 30 forms a first closed cross-sectional shape A that extends in the vehicle width direction by the cooperation of the step portion 22 and the floor reinforcement force 30, and the step portion 22 and the flooring The shape of the force 30 is constrained, and the rigidity of the front portion of the rear floor panel 20 is ensured, particularly the rigidity against a load acting from the vehicle width direction.
[0054]
Next, as shown in FIG. 4, the tunnel of the cross member 50 is interposed at the center portion in the vehicle width direction of the front flange 23 formed in the step portion 22 of the rear floor panel 20 via the mounting flange 38 of the floor reinforcement 30. The front joint portion 55 formed in the joint portion 53 is superposed from below, and the lower flange 56 is superposed on the stepped portion 22 via the lower flange 36 of the floor reinforcement 30, and FIG. As shown, the upper flange 58 formed on the upper edge of the rear surface 51 is overlapped with the lower surface of the rear floor surface 21 through the seat mounting reinforcement 60.
[0055]
Then, the front flange 23 of the rear floor panel 20, the mounting flange 38 of the floor reinforcement 30, and the tunnel coupling portion 53 of the cross member 50 are joined together by spot welding as indicated by circles in FIG. Similarly, the step portion 22 of the rear floor panel 20 that overlaps, the lower flange 36 of the floor reinforcement 30, and the front joint portion 55 formed in the tunnel joint portion 53 of the cross member 50 are spot welded together, and the cross member An upper flange 50 formed on the upper edge of the rear surface 51 of the 50 is spot-welded to the rear floor surface 21, and the rear floor panel 20, the floor reinforcement 30 and the cross member 50 are integrally coupled to form the rear floor portion RF.
[0056]
In addition to the first closed cross-sectional shape A formed by the step portion 22 of the rear floor panel 20, the rear floor portion RF formed in this way is further coupled to the rear floor panel 20, the floor reinforcement 30 and the cross member 50. A second closed cross-sectional shape B that accommodates the floor reinforcement 30 and extends in the vehicle body width direction is formed, and the shapes of the rear floor panel 20 and the cross member 20 are constrained to further ensure the rigidity of the front portion of the rear floor panel 50. The
[0057]
In the spot welded joints of these rear floor portions RF, the number of superposed members in each spot welded joint is within three, and the pressure and current density at the time of spot welding are sufficiently secured, uniform and sufficient. Bond strength is obtained.
[0058]
Next, the connection between the rear part of the front floor part FF thus formed and the front part of the rear floor part RF will be described.
[0059]
With the second rear flange 14 formed at the top rear end of the tunnel portion 12 formed in the front floor panel 10 and the mounting flange 38 projectingly formed on the floor reinforcement 30, the front floor panel 10 The front flange 23 of the rear floor panel 20 is overlapped on the lower surface of the rear flange 13 from below, and the tunnel coupling portion 53 of the cross member 50 is coupled to the lower surface of the rear flange 41 of the tunnel reinforcement 40 spot welded to the tunnel 12 from below. The front end flange 54 formed in the above is superposed.
[0060]
5, the rear flange 13 of the front floor panel 10 that overlaps between the second rear flanges 14 formed at the top rear end edge of the tunnel 12, and the front flange 23 of the rear floor panel 20, The front joint 55 formed on the tunnel joint 53 of the cross member 50 is spot welded together.
[0061]
Similarly, as indicated by a cross in FIG. 6, at the position near the side end of the rear end of the top of the tunnel portion 12, in other words, at a position where the coupling flange 38 is not interposed outside the coupling flange 38 formed in the floor reinforcement 30. Spot welded joints are made in the vicinity of both ends of the top portion of the tunnel portion 12 of the rear flange 13 that overlap with each other, the front flange 23 of the rear floor panel 20, and both ends of the front joint portion 55 formed in the tunnel joint portion 53. .
[0062]
Further, as shown by x in FIG. 4, the tunnel reinforcement joint portion 16 formed in the overlapping tunnel portion 12, the rear flange 41 of the tunnel reinforcement 40 spot welded to the tunnel 12, and the cross member 50. The front end flange 54 formed in the tunnel joint portion 53 is spot welded together.
[0063]
Accordingly, the rear end portion of the tunnel 12 formed in the front floor panel 10 around the rear end portion of the top portion of the tunnel 12, the center portion of the step portion 22 formed in the rear floor panel 20, and the lower surface 33 formed in the floor reinforcement 30. , The rear end portion of the tunnel reinforcement 40 and the tunnel coupling portion 53 projecting from the lower surface 52 of the cross member 50 are coupled to each other, and the number of superposed members in each spot welding coupling is within 3 each. There is sufficient pressure and current density during spot welding, and stable bond strength can be obtained.
[0064]
Further, the rear flange 13 formed at the rear edge of the front floor surface 11 that overlaps also at the rear edge 12 of the front floor surface 11 of the front floor panel 10 and the lower edge of the step portion 22 of the rear floor panel 20 are bent. The front flange 23 is joined by spot welding, and the third rear flange 15 is formed continuously with the rear flange 13 which overlaps with each other, the front flange 23 corresponding to the third flange 15, and the cross member 50. The joint flange 57 formed in the above is spot welded.
[0065]
The floor FL in which the front floor portion FF and the rear floor portion FR are firmly joined in this way is a toe board (front end of the front floor panel 10 and the tunnel reinforcement 40 that partitions the engine room and the vehicle compartment). The lower end of (not shown) is joined.
[0066]
A side sill (not shown) having a closed cross section extending in the longitudinal direction of the vehicle body is coupled to a side edge of the floor FL by a side sill inner and a side sill outer. More specifically, the side flanges 19, 29, 39, 59 bent at the outer edges of the front floor panel 10, the rear floor panel 20, the floor reinforcement 30, and the cross member 50 are superposed on the side sill inner of the side sill. And spot welded.
[0067]
Further, on the front floor surface 11 of the front floor panel 10, a seat support cross member (not shown) is provided between the side chassis and the tunnel 12 and supports the front seat.
[0068]
According to the vehicle body floor structure according to the present embodiment configured as described above, the closed cross-sectional shape A extending in the vehicle body width direction is formed by the cooperation of the rear floor panel 20 and the flooring force 30, and the closed cross-sectional shape is further formed. A closed cross-sectional shape B is formed by the rear floor panel 20 and the cross member 50 so as to accommodate A. In other words, double closed cross-sectional shapes A and B are formed in the vehicle body width direction, and the shape of the floor 1 in the vehicle body width direction is constrained, and the impact load acting from the side of the vehicle body is efficiently distributed and transmitted to other vehicle body parts. As a result, the safety of the vehicle body floor 1 and thus the deformation of the passenger compartment is prevented.
[0069]
Further, the tunnel portion 12 of the front floor 10 is stiffened by the tunnel reinforcement 40 in the front-rear direction, and the tunnel portion 12 and the tunnel reinforcement 40 are coupled to the tunnel coupling portion 53 extended to the floor reinforcement 30. Thus, the front floor portion FF and the rear floor portion FR are firmly coupled to ensure the longitudinal rigidity of the floor 1 to prevent the deformation of the floor 1, and as a result, when the impact load from the longitudinal direction of the vehicle body acts, the impact load Is efficiently distributed and transmitted to other vehicle body parts via the floor 1 to improve safety.
[0070]
In the above description, the tunnel coupling portion 53 protruding from the rear floor portion RF along the tunnel portion 12 of the front floor 10 is formed on the cross member 50. However, the present invention is appropriately formed on the rear floor panel 20, the floor reinforcement member 30 and the like. The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the invention.
[0071]
【The invention's effect】
According to the vehicle body floor structure and the vehicle body floor structure manufacturing method of the present invention described above, the closed cross-sectional shape is formed by the cooperation of the rear floor panel and the floor reinforcement and the rear floor panel and the cross member, respectively, from the side of the vehicle body on the floor. The deformation due to the acting impact load is suppressed and the deformation of the passenger compartment is prevented and the safety is improved. The tunnel portion of the front floor is stiffened by the tunnel reinforcement in the front-rear direction, and the tunnel portion and the tunnel link The force is coupled with the tunnel coupling part extending from the rear floor part, and the front floor part and the rear floor part are firmly coupled to secure the rigidity of the floor in the front-rear direction, the deformation of the floor is prevented, and the vehicle body from the front-rear direction is prevented. When an impact load is applied, the impact load is efficiently distributed and transmitted to other vehicle body parts via the floor. In which large becomes possible to contribute to improving the safety of an equal vehicle all sex is improved.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an outline of an embodiment of a vehicle body floor structure and a method for manufacturing a vehicle body floor structure according to the present invention.
FIG. 2 is a cross-sectional view taken along line AA of FIG.
FIG. 3 is an enlarged perspective view of a portion B in FIG. 1 in a state where respective members are coupled.
4 is a cross-sectional view taken along the line CC in FIG. 3. FIG.
5 is a cross-sectional view taken along the line DD in FIG. 3. FIG.
6 is a cross-sectional view taken along line EE in FIG.
FIG. 7 is a perspective view showing an outline of a conventional vehicle body floor structure.
FIG. 8 is a perspective view showing an outline of a conventional vehicle body floor structure.
[Explanation of symbols]
1 Body floor
10 Front floor panel
11 Front floor
12 Tunnel part
13 Rear flange
16 Tunnel reinforcement joint
20 Rear floor panel
21 Rear floor
22 steps
23 Front flange
30 floor reinforcement
31 Upper surface
32 Rear side
33 Bottom
38 Mounting flange
40 Tunnel Reinforce
41 Rear flange
50 cross members
51 rear
52 Bottom
53 Tunnel junction
54 Front flange
55 Front joint
FF front floor
RF rear floor

Claims

A front part of a rear floor panel in which a step part is formed on a front part of a rear floor surface is coupled to a rear part of a front floor panel in which a tunnel part extending in a longitudinal direction of the vehicle body is formed. In the vehicle body floor structure that forms a closed cross-sectional shape extending in the vehicle body width direction by installing a cross member between
A front floor panel in which a tunnel portion extending in the longitudinal direction of the vehicle body is formed at the center of the front floor surface;
A tunnel reinforcement disposed in the longitudinal direction of the vehicle body along the lower surface of the top of the tunnel,
A rear floor panel in which a step portion is formed at a front portion of the rear floor surface, and a lower end of the step portion is coupled to a rear portion of the front floor including the tunnel portion;
A first closed section extending in the vehicle body width direction in cooperation with the step portion, having flanges formed on the upper edge and the lower edge coupled to the step portion of the rear floor panel and extending in the vehicle body width direction A floor reinforcement which forms a shape and whose lower edge is coupled to the tunnel portion ;
A cross member that is constructed between the stepped portion and the rear floor surface and accommodates the floor reinforcement and forms a second closed cross-sectional shape extending in the vehicle body width direction;
At least one of the lower step portion of the rear floor, the floor reinforcement, and the cross member includes a tunnel coupling portion that extends forward of the vehicle body along the bottom lower surface of the tunnel portion and is coupled to the tunnel portion and the tunnel reinforcement. Body floor structure characterized by that.

A front part of a rear floor panel in which a step part is formed on a front part of a rear floor surface is coupled to a rear part of a front floor panel in which a tunnel part extending in a longitudinal direction of the vehicle body is formed. In the vehicle body floor structure that forms a closed cross-sectional shape extending in the vehicle body width direction by installing a cross member between
A front floor panel in which a tunnel portion extending in the longitudinal direction of the vehicle body is formed at the center of the front floor surface;
A tunnel reinforcement disposed in the longitudinal direction of the vehicle body along the lower surface of the top of the tunnel,
A rear floor panel having a stepped portion formed at the front of the rear floor surface;
A first closed section extending in the vehicle body width direction in cooperation with the step portion, having flanges formed on the upper edge and the lower edge coupled to the step portion of the rear floor panel and extending in the vehicle body width direction A floor reinforcement which forms a shape and whose lower edge is coupled to the tunnel portion ;
A second closed cross-sectional shape extending between the step portion and the rear floor surface to accommodate the floor reinforcement and extending in the vehicle body width direction is formed along the bottom lower surface of the top portion of the tunnel portion. A cross member having an extended tunnel coupling portion,
The lower part of the step of the rear floor panel, the floor reinforcement and the cross member are spot welded together, the top of the tunnel part, the tunnel reinforcement and the tunnel joint of the cross member are spot welded together, and the tunnel part The vehicle body floor structure is characterized in that the top of the door, the lower part of the step of the rear floor panel, and the cross member are joined together by spot welding.

Spot welding connection between the lower part of the stepped portion of the rear floor panel, the floor reinforcement and the cross member,
A mounting flange projecting from the edge of the floor reinforcement so as to be superposed on a portion corresponding to the top of the tunnel portion;
A front flange formed on the lower edge of the stepped portion of the rear floor panel;
3. The front coupling portion formed in the tunnel coupling portion of the cross member is superposed, and the mounting flange, front flange, and front coupling portion to be superposed are spot welded together. Car body floor structure.

Spot welding connection between the top of the tunnel part, the lower part of the step part of the rear floor panel, and the cross member is as follows:
A rear flange formed in the tunnel portion;
A front flange formed at the bottom of the stepped portion of the rear floor panel;
3. The front joint formed on the tunnel joint portion of the cross member is superposed, and the superposed rear flange, front flange, and front joint portion are spot welded together. Or the vehicle body floor structure according to 3.

Spot welding connection between the lower part of the stepped portion of the rear floor panel, the floor reinforcement and the cross member,
A plurality of mounting flanges that protrude from the lower edge of the floor reinforcement to be spaced apart from each other in a portion corresponding to the top of the tunnel portion, and
A front flange formed at the bottom of the stepped portion of the rear floor panel;
The front joint formed on the tunnel joint of the cross member is superposed, and the mounting flange, front flange and front joint to be superposed are spot welded together,
Spot welding connection between the top of the tunnel part, the lower part of the step part of the rear floor panel, and the cross member is as follows:
A rear flange formed in the tunnel portion;
The front flange formed at the bottom of the stepped portion of the rear floor panel;
The front joint formed on the tunnel joint of the cross member is superposed, and the superposed rear flange, front flange, and front joint are spotted at non-overlapping portions between the plurality of mounting flanges. The vehicle body floor structure according to claim 2 or 3, wherein the vehicle body floor structure is welded.

6. The vehicle body floor structure according to claim 5, wherein the overlapping rear flange, front flange, and front joint portion are spot-welded to each other outward in the vehicle width direction from the plurality of mounting flanges.

Spot welding connection between the top of the tunnel part, the tunnel reinforcement and the tunnel joint part of the cross member,
A tunnel reinforcement coupling portion formed in the tunnel portion;
A rear flange formed at the rear end of the tunnel reinforcement;
The front end flange formed at the front end of the tunnel joint portion is superposed, and the superposed tunnel reinforcement joint portion, the rear flange, and the front end flange are spot-welded joined . The vehicle body frame structure according to item 1 .

8. The vehicle body frame structure according to claim 7, wherein a tunnel reinforcement coupling portion is formed in front of the vehicle body from a rear end flange formed in the tunnel portion.

A front part of a rear floor panel in which a step part is formed on a front part of a rear floor surface is coupled to a rear part of a front floor panel in which a tunnel part extending in a longitudinal direction of the vehicle body is formed. In the manufacturing method of a vehicle body floor structure in which a cross member is installed between the two to form a closed cross-sectional shape extending in the vehicle body width direction,
Front floor panel having a tunnel portion extending in the longitudinal direction of the vehicle body at the center of the front floor surface, a rear flange formed at the rear end of the tunnel portion, and a tunnel reinforcement coupling portion formed in front of the rear flange When,
A tunnel reinforcement disposed in the front-rear direction along the lower surface of the top of the tunnel portion and having a rear flange capable of being superposed on the tunnel reinforcement joint at the rear end;
A rear floor panel in which a step portion is formed at the front portion of the rear floor surface, and a front flange that can be overlapped with a rear flange formed in the front floor panel is formed at the lower end of the step portion,
A first closed section extending in the vehicle body width direction in cooperation with the step portion, having flanges formed on the upper edge and the lower edge coupled to the step portion of the rear floor panel and extending in the vehicle body width direction A floor reinforcement formed with a mounting flange capable of being superimposed on the rear flange of the tunnel portion and the front flange of the rear floor panel , while forming a shape;
A second closed cross-sectional shape extending between the step portion and the rear floor surface to accommodate the floor reinforcement and extending in the vehicle body width direction is formed along the bottom lower surface of the top portion of the tunnel portion. An extended tunnel coupling portion is formed on the tunnel coupling portion, a rear flange formed on the tunnel portion and a front flange formed on a rear floor panel, and an upper coupling portion that can be polymerized, and the tunnel reinforcement. A cross member having a front flange that can be superposed on the rear flange;
The front floor panel is joined to the tunnel reinforcement joint portion of the front floor panel by spot welding the rear flange of the tunnel reinforcement to form a front floor portion in which the front floor panel and the tunnel reinforcement are integrally joined,
The front flange of the rear floor panel, the mounting flange of the floor reinforcement, and the front joint portion of the cross member are overlapped and spot welded together to integrally join the rear front panel, the floor reinforcement, and the cross member. Forming a rear floor,
The tunnel reinforcement joint part formed in the tunnel part of the front floor, the rear flange of the tunnel reinforcement and the front end flange of the tunnel joint part formed in the cross member are overlapped and spot welded together, and the rear part of the front floor panel A method of manufacturing a vehicle body floor structure, wherein the front floor portion and the rear floor portion are connected by superimposing a flange, a front flange of a rear floor panel, and a front joint portion of a cross member and spot welding together .