JP4003643B2

JP4003643B2 - Car body rear structure

Info

Publication number: JP4003643B2
Application number: JP2003011474A
Authority: JP
Inventors: 周橋本
Original assignee: Nissan Motor Co Ltd
Current assignee: Nissan Motor Co Ltd
Priority date: 2003-01-20
Filing date: 2003-01-20
Publication date: 2007-11-07
Anticipated expiration: 2023-01-20
Also published as: JP2004224087A

Description

【０００１】
【発明の属する技術分野】
本発明は自動車の車体後部構造に関する。
【０００２】
【従来の技術】
従来の車体後部構造としては、サイドシルの後端部の車幅方向内側の側壁にリアサイドメンバの前端部を結合し、リアサスペンションのトレーリングアームの前側ブッシュを取り付けるブラケットを、このリアサイドメンバの前端部の底面に結合するようにしている（例えば、特許文献１参照。）。
【０００３】
【特許文献１】
特開２００１−１６３２６２号公報（第３頁、第３図）
【０００４】
【発明が解決しようとする課題】
しかしながら、かかる従来の車体後部構造では、トレーリングアームのブラケットをリアサイドメンバの底面に結合してあるので、ブラケットがリアサイドメンバの底面から更に下方に突出することになり、最低地上高を確保する（高くする）ためには、リアサイドメンバの底面位置を高くする必要がある。
【０００５】
このようにリアサイドメンバの底面位置を高くするとリアサイドメンバの上下高さが必然的に低くなるため、このリアサイドメンバの高さ方向断面が減少して上下方向の強度が低下し、後面衝突による荷重入力によってリアサイドメンバに上方への曲げモーメントが作用した場合に、このリアサイドメンバが変形し易くなってしまうことから、リアサイドメンバの板厚を増厚したり補強部材を追加して強度を増大する必要があるため、重量増加を招くとともに、コストアップを来してしまう。
【０００６】
そこで、本発明は板厚を厚くしたり補強部材を追加することなく、リアサイドメンバの強度を増大することができる車体後部構造を提供するものである。
【０００７】
【課題を解決するための手段】
本発明にあっては、車幅方向両側に車体前後方向に延在配置したサイドシルと、このサイドシルの後端部に連結されサイドシルに対して車幅方向内側にオフセットして車体前後方向に延在配置したリアサイドメンバと、このリアサイドメンバに取り付けられたリアサスペンションアームと、を備えた車体後部構造において、リアサイドメンバの前端部分を底面を下げて高さ方向断面を増大するとともに、リアサイドメンバのサイドシルとの結合部近傍の下部に、下側を開放し上側を中間壁としたブラケット収納部を設け、このブラケット収納部にリアサスペンションアームの前側ブッシュを支持する第１，第２ブラケットを車幅方向に対峙させて設けるとともに、車幅方向外側に配置した第２ブラケットを車幅方向内側に偏寄させて配置したことを特徴としている。
【０００８】
【発明の効果】
本発明によれば、リアサイドメンバの前端部分の高さ方向断面を増大したので、特に上下方向の強度を高めることができ、後面衝突による荷重入力によってリアサイドメンバに作用する上方への曲げモーメントに対して曲げ変形を抑制することができる。
【０００９】
従って、リアサイドメンバの強度を、板厚を増厚したり補強部材を追加することなく増大できるので、重量の大幅な増加を招くことがなく、かつ、コストアップを抑制することができる。
【００１０】
また、リアサイドメンバのサイドシルとの結合部近傍の下部にブラケット収納部を設けて、このブラケット収納部にリアサスペンションアームの前側ブッシュを支持する第１，第２ブラケットを設けたので、地上高を確保し易くなる。
【００１１】
しかも、第１，第２ブラケットとサイドシル後端との間にリアサイドメンバの潰れスペースを確保できるので、後面衝突に対してリアサイドメンバの前端部が潰れ変形してエネルギー吸収することができる。
【００１２】
更に、前記第１，第２ブラケットのうち、車幅方向外側に配置した第２ブラケットのみを車幅方向内側に偏寄させてあるが、この第２ブラケット配置部以外の部分ではリアサイドメンバの断面の大きさを確保できるため、その部分での強度低下を最小限に抑えることができる。
【００１３】
【発明の実施の形態】
以下、本発明の実施形態を図面と共に詳述する。
【００１４】
図１〜図６は本発明にかかる車体後部構造の一実施形態を示し、図１はサイドシルとリアサイドメンバの連結部分を示す斜視図、図２はサイドシルとリアサイドメンバの連結部分を示す平面図、図３はサイドシルとリアサイドメンバの連結部分を示す側面図、図４は図２中Ａ−Ａ線に沿った拡大断面図、図５はサイドシルとリアサイドメンバの連結部分の変形作用を説明する平面図、図６はサイドシルとリアサイドメンバの連結部分の変形作用を説明する側面図である。
【００１５】
本実施形態の車体後部構造は、図１〜図３に示すように図外の車体フロアの車幅方向両側に位置して車体前後方向に延在配置したサイドシル１と、このサイドシル１の後端部に連結されサイドシル１に対して車幅方向内側かつ上方にオフセットして車体前後方向に延在配置したリアサイドメンバ２と、このリアサイドメンバ２に取り付けられたリアサスペンションアームとしてのトレーリングアーム３と、を備えている。
【００１６】
上記サイドシル１は断面矩形状の閉断面構造となっており、このサイドシル１の後端部１ａに内向きの傾斜面１ｂを形成して、この傾斜面１ｂにリアサイドメンバ２の前端部２ａを車幅方向外側に若干湾曲させて連結し、このリアサイドメンバ２のサイドシル１への連結部分よりも後方となる一般部分をサイドシル１に対して車幅方向内側にオフセットさせてある。
【００１７】
リアサイドメンバ２は、一般部分が底面２ｂとその両側から立ち上がる１対の縦壁２ｃ，２ｄとによって断面Ｕ字状に形成され、その縦壁２ｃ，２ｄの上端を図外のフロアパネル下面に結合することにより閉断面として構成される。
【００１８】
上記トレーリングアーム３の前端部には、同心配置した内筒，外筒間にゴムを加硫接着した一般的な構造となる前側ブッシュ３ａが設けられ、この前側ブッシュ３ａをリアサイドメンバ２の前端部に取り付けるようにしている。
【００１９】
ここで、本実施形態ではリアサイドメンバ２の前端部分を底面２ｂを下げて高さ方向断面を増大するとともに、図４に示すようにリアサイドメンバ２のサイドシル１との結合部近傍の下部に、下側を開放し上側を中間壁２ｅとしたブラケット収納部４を設け、このブラケット収納部４に前側ブッシュ３ａを支持する第１，第２ブラケット５，５ａを車幅方向に対峙させて設けるとともに、車幅方向外側に配置した第２ブラケット５ａを車幅方向内側に偏寄（寸法ｄ）させてある。
【００２０】
上記中間壁２ｅは、リアサイドメンバ２の一般部分の底面２ｂから連続して成形され、この中間壁２ｅの下面から上記第１，第２ブラケット５，５ａを一体に垂設してある。
【００２１】
第１ブラケット５は車幅方向内側に配置されるとともに、第２ブラケット５ａは車幅方向外側に配置され、これら第１，第２ブラケット５，５ａ間に上記前側ブッシュ３ａを挟むように嵌合した状態で、この前側ブッシュ３ａを第１，第２ブラケット５，５ａに跨って挿通した取付ボルト６（図４参照）を介して支持する。
【００２２】
また、図２に示すようにこの第２ブラケット５ａはサイドシル１に対して車幅方向にオーバーラップ（オーバーラップ量Ｌ）させてある。
【００２３】
更に、図１，図４に示すように中間壁２ｅの上側に、第１，第２ブラケット５，５ａにそれぞれ対応させて車体前後方向に延在する第１，第２リブ７，８を設けてある。
【００２４】
上記第１，第２ブラケット５，５ａのうち、図４に示すように第１ブラケット５を厚肉形成して雌ねじ部６ａを形成し、この雌ねじ部６ａに上記取付ボルト６のねじ部を螺合するようにして、第１ブラケット５を取付ボルト６に対するナット部分としてある。
【００２５】
また、上記中間壁２ｅと第１リブ７とに亘って、第１ブラケット５に対応させて車幅方向に延在する第３リブ９を設けるとともに、上記第２リブ８と中間壁２ｅとリアサイドメンバ２の車幅方向外側の縦壁２ｃとで囲まれたＵ字状内側面に、車幅方向に延在する第４リブ１０を設けてある。
【００２６】
更に、上記第１リブ７の前端位置Ｋｆを、図２に示すようにサイドシル１の車幅方向内側の縦壁１ｃの後端Ｋｒよりも車幅方向内側にオフセット（オフセット量ｆ）して設定し、これら第１リブ７の前端Ｋｆとサイドシル１の車幅方向内側の縦壁１ｃの後端Ｋｒとを連結する第５リブ１１を設けてある。
【００２７】
ところで、本実施形態のリアサイドメンバ２は、上述したように第１，第２ブラケット５，５ａおよび第１〜第５リブ７〜１１を付設したが、これらブラケット５，５ａおよびリブ７〜１１を含めてリアサイドメンバ２をアルミ合金の鋳物として一体成形している。
【００２８】
以上の構成により本実施形態の後部車体構造にあっては、リアサイドメンバ２の前端部分を底面２ｂを下げてこのリアサイドメンバ２の高さ方向断面を増大しているので、リアサイドメンバ２の特に上下方向の強度を高めることができる。
【００２９】
このため、後面衝突による衝突荷重Ｆが入力した場合に、この荷重Ｆによってリアサイドメンバ２に上方への曲げモーメントＭ１（図３参照）が発生するが、高さ方向断面の増大により曲げモーメントＭ１に対する曲げ変形を抑制することができる。
【００３０】
従って、リアサイドメンバ２の強度を、板厚を増厚したり補強部材を追加することなく増大できるので、重量の大幅な増加を招くことなく、かつ、コストアップを抑制することができる。
【００３１】
また、リアサイドメンバ２のサイドシル１との結合部近傍の下部にブラケット収納部４を設けて、このブラケット収納部４にトレーリングアーム３の前側ブッシュ３ａを支持する第１，第２ブラケット５，５ａを設けたので、地上高を確保し易くなる。
【００３２】
しかも、第１，第２ブラケット５，５ａとサイドシル１の後端との間にリアサイドメンバ２の潰れスペースを確保できるので、リアオーバーハングを大きくする必要がなく後面衝突に対して図５，図６に示すようにリアサイドメンバ２が潰れ変形してエネルギー吸収することができる。
【００３３】
更に、前記第１，第２ブラケット５，５ａのうち、車幅方向外側に配置した第２ブラケット５ａのみを車幅方向内側に偏寄させてあるが、この第２ブラケット５ａを配置した以外の部分ではリアサイドメンバ２の断面の大きさを確保できるため、その部分での強度低下を最小限に抑えることができる。
【００３４】
また、本実施形態では上記作用効果に加えて、第２ブラケット５ａをサイドシル１に対して車幅方向にオーバーラップさせたので、トレーリングアーム３を介して入力される車体後方からの衝突荷重Ｆを効率良くサイドシル１に伝達することができる。
【００３５】
また、中間壁２ｅの上面に、第１，第２ブラケット５，５ａにそれぞれ対応させて車体前後方向に延在する第１，第２リブ７，８を設けたので、リアサイドメンバ２のサイドシル１への連結側端部近傍に作用する上下モーメントＭ１に対する強度を更に増大して、リアサイドメンバ２からサイドシル１への衝突荷重Ｆの伝達量を増大することができる。
【００３６】
更に、第１ブラケット５に雌ねじ部６ａを形成して、取付ボルト６に対するナット部分としたので、前側ブッシュ３ａを第１，第２ブラケット５，５ａに支持する際に、車体外方から取付ボルト６を挿入して締め付けることができるため、トレーリングアーム３の取付作業性を向上することができる。
【００３７】
更にまた、中間壁２ｅの上面と第１リブ７とに亘って、第１ブラケット５に対応させて車幅方向に延在する第３リブ９を設けたので、リアサスペンションから入力される上下方向の荷重により前側ブッシュ３ａに発生するモーメントＭ２（図４参照）に対する強度を増大することができる。
【００３８】
また、第２リブ８と中間壁２ｅとリアサイドメンバ２の車幅方向外側の縦壁２ｃとで囲まれたＵ字状内側面に、車幅方向に延在する第４リブ１０を設けたので、前記モーメントＭ２に対する強度を更に増大することができる。
【００３９】
更に、第１リブ７の前端位置Ｋｆを、サイドシル１の車幅方向内側の縦壁１ｃの後端Ｋｒよりも車幅方向内側にオフセットして設定し、これら第１リブ７の前端Ｋｆとサイドシル１の車幅方向内側の縦壁１ｃの後端Ｋｒとを第５リブ１１によって連結したので、トレーリングアーム３を介して入力される車体後方からの荷重に対する強度を増大することができるとともに、この車体後方からの荷重に対して第５リブ１１が傾斜しているため、図５に示すようにこの第５リブ１１が座屈変形して前記リアサイドメンバ前端部の変形によるエネルギー吸収を妨げるのを防止する。
【００４０】
更にまた、リアサイドメンバ２を、これに付設する第１，第２ブラケット５，５ａや第１〜第５リブ７〜１１を含めてアルミ合金の鋳物として一体成形したので、部品点数を削減できるとともに、リアサイドメンバ２を比較的容易に形成することができ、生産性の向上を図ることができるとともに、軽量化を達成することができる。
【００４１】
ところで、本発明の車体後部構造は上記実施形態に例をとって説明したが、この実施形態に限ることなく本発明の要旨を逸脱しない範囲で他の実施形態を各種採ることができる。
【図面の簡単な説明】
【図１】本発明の一実施形態におけるサイドシルとリアサイドメンバの連結部分を示す斜視図。
【図２】本発明の一実施形態におけるサイドシルとリアサイドメンバの連結部分を示す平面図。
【図３】本発明の一実施形態におけるサイドシルとリアサイドメンバの連結部分を示す側面図。
【図４】図２中Ａ−Ａ線に沿った拡大断面図。
【図５】本発明の一実施形態におけるサイドシルとリアサイドメンバの連結部分の変形作用を説明する平面図。
【図６】本発明の一実施形態におけるサイドシルとリアサイドメンバの連結部分の変形作用を説明する側面図。
【符号の説明】
１サイドシル
２リアサイドメンバ
２ｂリアサイドメンバの底面
２ｃ，２ｄリアサイドメンバの縦壁
２ｅ中間壁
３トレーリングアーム（リアサスペンションアーム）
３ａ前方ブッシュ
４ブラケット収納部
５第１ブラケット（ナット部）
５ａ第２ブラケット
６取付ボルト
７第１リブ
８第２リブ
９第３リブ
１０第４リブ
１１第５リブ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rear body structure of an automobile.
[0002]
[Prior art]
As a conventional vehicle body rear structure, the front end portion of the rear side member is coupled to the side wall in the vehicle width direction of the rear end portion of the side sill, and the bracket for attaching the front bush of the trailing arm of the rear suspension is attached to the front end portion of the rear side member. (See, for example, Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-163262 (page 3, FIG. 3)
[0004]
[Problems to be solved by the invention]
However, in such a conventional vehicle body rear structure, since the bracket of the trailing arm is coupled to the bottom surface of the rear side member, the bracket projects further downward from the bottom surface of the rear side member, thereby ensuring a minimum ground clearance ( In order to increase the height, the bottom surface position of the rear side member needs to be increased.
[0005]
When the bottom position of the rear side member is increased in this way, the vertical height of the rear side member inevitably decreases, so the cross section in the height direction of the rear side member decreases, the vertical strength decreases, and load input due to rear collision When an upward bending moment acts on the rear side member, the rear side member becomes easily deformed. Therefore, it is necessary to increase the thickness of the rear side member or add a reinforcing member to increase the strength. As a result, the weight is increased and the cost is increased.
[0006]
Accordingly, the present invention provides a vehicle body rear structure that can increase the strength of the rear side member without increasing the plate thickness or adding a reinforcing member.
[0007]
[Means for Solving the Problems]
In the present invention, a side sill extending in the vehicle longitudinal direction on both sides in the vehicle width direction and connected to the rear end of the side sill is offset inward in the vehicle width direction with respect to the side sill and extends in the vehicle longitudinal direction. In a vehicle body rear structure having a rear side member arranged and a rear suspension arm attached to the rear side member, the front end portion of the rear side member is lowered to increase the cross section in the height direction, and the side sill of the rear side member A bracket housing part with the lower side open and the upper side as an intermediate wall is provided in the lower part near the coupling part, and the first and second brackets for supporting the front bush of the rear suspension arm are arranged in the vehicle width direction in the bracket housing part. The second bracket arranged on the outer side in the vehicle width direction is offset and arranged on the inner side in the vehicle width direction. It is characterized by a door.
[0008]
【The invention's effect】
According to the present invention, since the height direction cross section of the front end portion of the rear side member is increased, the strength in the vertical direction can be particularly increased, and the upward bending moment acting on the rear side member due to the load input due to the rear surface collision can be increased. Thus, bending deformation can be suppressed.
[0009]
Therefore, the strength of the rear side member can be increased without increasing the plate thickness or adding a reinforcing member, so that a significant increase in weight is not caused and an increase in cost can be suppressed.
[0010]
In addition, a bracket housing part is provided in the lower part of the rear side member near the side sill, and the bracket housing part is provided with the first and second brackets for supporting the front bush of the rear suspension arm. It becomes easy to do.
[0011]
In addition, since the crushing space of the rear side member can be ensured between the first and second brackets and the rear end of the side sill, the front end portion of the rear side member can be crushed and deformed to absorb energy against a rear collision.
[0012]
Further, of the first and second brackets, only the second bracket arranged on the outer side in the vehicle width direction is biased toward the inner side in the vehicle width direction. Therefore, the strength reduction at that portion can be minimized.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0014]
1 to 6 show an embodiment of a vehicle body rear structure according to the present invention, FIG. 1 is a perspective view showing a connecting portion between a side sill and a rear side member, and FIG. 2 is a plan view showing a connecting portion between the side sill and a rear side member. 3 is a side view showing the connecting portion between the side sill and the rear side member, FIG. 4 is an enlarged cross-sectional view taken along line AA in FIG. 2, and FIG. 5 is a plan view for explaining the deformation action of the connecting portion between the side sill and the rear side member. FIG. 6 is a side view for explaining the deformation action of the connecting portion between the side sill and the rear side member.
[0015]
As shown in FIGS. 1 to 3, the vehicle body rear structure of the present embodiment includes a side sill 1 that is positioned on both sides in the vehicle width direction of the vehicle body floor (not shown) and extends in the vehicle longitudinal direction, and a rear end of the side sill 1. A rear side member 2 that is connected to the side sill 1 and is offset inward in the vehicle width direction with respect to the side sill 1 and extends in the vehicle front-rear direction, and a trailing arm 3 as a rear suspension arm attached to the rear side member 2 It is equipped with.
[0016]
The side sill 1 has a closed cross-sectional structure with a rectangular cross section. An inwardly inclined surface 1b is formed at the rear end 1a of the side sill 1, and the front end 2a of the rear side member 2 is mounted on the inclined surface 1b. The rear side member 2 is slightly curvedly connected to the outside in the width direction and connected to the side sill 1 of the rear side member 2 so that a general portion behind the side sill 1 is offset inward in the vehicle width direction.
[0017]
The rear side member 2 is formed in a U-shaped cross section by a general portion having a bottom surface 2b and a pair of vertical walls 2c, 2d rising from both sides thereof, and the upper ends of the vertical walls 2c, 2d are coupled to the lower surface of the floor panel (not shown). By doing so, it is configured as a closed section.
[0018]
A front bush 3a having a general structure in which rubber is vulcanized and bonded between an inner cylinder and an outer cylinder arranged concentrically is provided at the front end portion of the trailing arm 3. The front bush 3a is connected to the front end of the rear side member 2. It is trying to attach to the part.
[0019]
Here, in the present embodiment, the front end portion of the rear side member 2 is lowered in the bottom surface 2b to increase the cross section in the height direction, and the lower side of the rear side member 2 near the coupling portion with the side sill 1 as shown in FIG. A bracket housing portion 4 having an open side and an intermediate wall 2e on the upper side is provided, and the bracket housing portion 4 is provided with first and second brackets 5 and 5a that support the front bush 3a facing each other in the vehicle width direction, The second bracket 5a disposed on the outer side in the vehicle width direction is offset (dimension d) toward the inner side in the vehicle width direction.
[0020]
The intermediate wall 2e is formed continuously from the bottom surface 2b of the general portion of the rear side member 2, and the first and second brackets 5 and 5a are integrally suspended from the lower surface of the intermediate wall 2e.
[0021]
The first bracket 5 is disposed on the inner side in the vehicle width direction, and the second bracket 5a is disposed on the outer side in the vehicle width direction, and is fitted so as to sandwich the front bush 3a between the first and second brackets 5 and 5a. In this state, the front bush 3a is supported via a mounting bolt 6 (see FIG. 4) inserted through the first and second brackets 5 and 5a.
[0022]
As shown in FIG. 2, the second bracket 5a overlaps the side sill 1 in the vehicle width direction (overlap amount L).
[0023]
Further, as shown in FIGS. 1 and 4, first and second ribs 7 and 8 extending in the longitudinal direction of the vehicle body are provided on the upper side of the intermediate wall 2e so as to correspond to the first and second brackets 5 and 5a, respectively. It is.
[0024]
Of the first and second brackets 5 and 5a, as shown in FIG. 4, the first bracket 5 is formed thick to form a female screw portion 6a, and the screw portion of the mounting bolt 6 is screwed into the female screw portion 6a. In this manner, the first bracket 5 is used as a nut portion for the mounting bolt 6.
[0025]
Further, a third rib 9 extending in the vehicle width direction corresponding to the first bracket 5 is provided across the intermediate wall 2e and the first rib 7, and the second rib 8, the intermediate wall 2e, and the rear side are provided. A fourth rib 10 extending in the vehicle width direction is provided on the U-shaped inner surface surrounded by the vertical wall 2c on the outer side in the vehicle width direction of the member 2.
[0026]
Further, the front end position Kf of the first rib 7 is set by offsetting (offset amount f) inward in the vehicle width direction from the rear end Kr of the vertical wall 1c in the vehicle width direction inside the side sill 1, as shown in FIG. A fifth rib 11 is provided to connect the front end Kf of the first rib 7 and the rear end Kr of the vertical wall 1c inside the side sill 1 in the vehicle width direction.
[0027]
By the way, the rear side member 2 of the present embodiment is provided with the first and second brackets 5 and 5a and the first to fifth ribs 7 to 11 as described above, but the brackets 5 and 5a and the ribs 7 to 11 are attached. Including, the rear side member 2 is integrally formed as an aluminum alloy casting.
[0028]
With the above-described configuration, in the rear vehicle body structure of the present embodiment, the bottom side 2b of the front end portion of the rear side member 2 is lowered to increase the height-direction cross section of the rear side member 2. The strength of the direction can be increased.
[0029]
Therefore, when a collision load F due to a rear collision is input, an upward bending moment M1 (see FIG. 3) is generated in the rear side member 2 due to the load F. However, due to the increase in the cross section in the height direction, the bending moment M1 is increased. Bending deformation can be suppressed.
[0030]
Accordingly, the strength of the rear side member 2 can be increased without increasing the plate thickness or adding a reinforcing member, so that a significant increase in weight can be prevented and an increase in cost can be suppressed.
[0031]
A bracket housing portion 4 is provided at a lower portion of the rear side member 2 in the vicinity of the coupling portion with the side sill 1, and the first and second brackets 5, 5 a for supporting the front bush 3 a of the trailing arm 3 on the bracket housing portion 4. Since it is provided, it becomes easy to ensure the ground clearance.
[0032]
In addition, since a space for crushing the rear side member 2 can be secured between the first and second brackets 5 and 5a and the rear end of the side sill 1, there is no need to increase the rear overhang, and the rear collision is shown in FIGS. As shown in FIG. 6, the rear side member 2 can be crushed and deformed to absorb energy.
[0033]
Further, of the first and second brackets 5 and 5a, only the second bracket 5a disposed on the outer side in the vehicle width direction is biased toward the inner side in the vehicle width direction, but other than the second bracket 5a being disposed. Since the size of the cross section of the rear side member 2 can be secured at the portion, the strength reduction at that portion can be minimized.
[0034]
In the present embodiment, in addition to the above-described effects, the second bracket 5a is overlapped in the vehicle width direction with respect to the side sill 1, so that a collision load F from the rear of the vehicle body input via the trailing arm 3 is obtained. Can be efficiently transmitted to the side sill 1.
[0035]
Further, since the first and second ribs 7 and 8 extending in the longitudinal direction of the vehicle body corresponding to the first and second brackets 5 and 5a are provided on the upper surface of the intermediate wall 2e, the side sill 1 of the rear side member 2 is provided. It is possible to further increase the strength against the vertical moment M1 acting in the vicinity of the connection side end to the rear side member 2 and increase the transmission amount of the collision load F from the rear side member 2 to the side sill 1.
[0036]
Further, since the female thread portion 6a is formed on the first bracket 5 to form a nut portion for the mounting bolt 6, when the front bush 3a is supported by the first and second brackets 5 and 5a, the mounting bolt is mounted from the outside of the vehicle body. Since 6 can be inserted and tightened, the mounting workability of the trailing arm 3 can be improved.
[0037]
Furthermore, since the third rib 9 extending in the vehicle width direction corresponding to the first bracket 5 is provided across the upper surface of the intermediate wall 2e and the first rib 7, the vertical direction input from the rear suspension The strength against the moment M2 (see FIG. 4) generated in the front bush 3a due to the load can be increased.
[0038]
Further, the fourth rib 10 extending in the vehicle width direction is provided on the U-shaped inner surface surrounded by the second rib 8, the intermediate wall 2e, and the vertical wall 2c on the outer side in the vehicle width direction of the rear side member 2. The strength against the moment M2 can be further increased.
[0039]
Further, the front end position Kf of the first rib 7 is set to be offset inward in the vehicle width direction from the rear end Kr of the vertical wall 1c on the inner side in the vehicle width direction of the side sill 1, and the front end Kf of the first rib 7 and the side sill 1 is connected to the rear end Kr of the vertical wall 1c on the inner side in the vehicle width direction by the fifth rib 11, so that the strength against the load from the rear of the vehicle body input via the trailing arm 3 can be increased. Since the fifth rib 11 is inclined with respect to the load from the rear of the vehicle body, as shown in FIG. 5, the fifth rib 11 buckles and prevents energy absorption due to the deformation of the front end portion of the rear side member. To prevent.
[0040]
Furthermore, since the rear side member 2 is integrally formed as an aluminum alloy casting including the first and second brackets 5 and 5a and the first to fifth ribs 7 to 11 attached thereto, the number of parts can be reduced. The rear side member 2 can be formed relatively easily, and productivity can be improved, and weight reduction can be achieved.
[0041]
By the way, although the vehicle body rear structure of the present invention has been described by taking the above embodiment as an example, the present invention is not limited to this embodiment, and various other embodiments can be adopted without departing from the gist of the present invention.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a connecting portion between a side sill and a rear side member in an embodiment of the present invention.
FIG. 2 is a plan view showing a connecting portion between a side sill and a rear side member in an embodiment of the present invention.
FIG. 3 is a side view showing a connecting portion between a side sill and a rear side member in an embodiment of the present invention.
4 is an enlarged sectional view taken along line AA in FIG.
FIG. 5 is a plan view for explaining the deformation action of the connecting portion between the side sill and the rear side member in the embodiment of the present invention.
FIG. 6 is a side view for explaining the deformation action of the connecting portion between the side sill and the rear side member in the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Side sill 2 Rear side member 2b Bottom surface 2c, 2d of rear side member Vertical wall 2e of rear side member Intermediate wall 3 Trailing arm (rear suspension arm)
3a Front bush 4 Bracket housing part 5 First bracket (nut part)
5a 2nd bracket 6 mounting bolt 7 1st rib 8 2nd rib 9 3rd rib 10 4th rib 11 5th rib

Claims

A side sill extending in the vehicle longitudinal direction on both sides in the vehicle width direction, a rear side member connected to the rear end of the side sill and offset inward in the vehicle width direction with respect to the side sill and extending in the vehicle longitudinal direction, In the vehicle body rear structure including a rear suspension arm attached to the rear side member,
The lower end of the front end portion of the rear side member is lowered to increase the cross section in the height direction, and a bracket housing portion with the lower side open and the upper side as an intermediate wall is provided at the lower portion near the side sill of the rear side member. The first and second brackets that support the front bush of the rear suspension arm are provided in the bracket housing portion so as to face each other in the vehicle width direction, and the second bracket disposed on the outer side in the vehicle width direction is offset toward the inner side in the vehicle width direction. The rear structure of the vehicle body characterized by the arrangement.

The vehicle body rear part structure according to claim 1, wherein at least the second bracket overlaps the side sill in the vehicle width direction.

The vehicle body rear part structure according to claim 1 or 2, wherein first and second ribs extending in the longitudinal direction of the vehicle body are provided on the upper surface of the intermediate wall so as to correspond to the first and second brackets, respectively.

The first bracket disposed on the inner side in the vehicle width direction is a nut portion for a mounting bolt of a rear suspension arm that is inserted across the first and second brackets. Car body rear structure as described.

5. The vehicle body rear structure according to claim 4, wherein a third rib extending in the vehicle width direction is provided so as to correspond to the first bracket over the upper surface of the intermediate wall and the first rib.

4. A fourth rib extending in the vehicle width direction is provided on the U-shaped inner surface surrounded by the second rib, the intermediate wall, and the vertical wall on the outer side in the vehicle width direction of the rear side member. Car body rear part structure as described in any one of -5.

The front end position of the first rib is set to be offset inward in the vehicle width direction from the rear end of the vertical wall inside the side sill in the vehicle width direction, and the front end of the first rib and the vertical wall inside the side sill in the vehicle width direction are set. The vehicle body rear part structure according to any one of claims 3 to 6, further comprising a fifth rib for connecting the rear end.

8. The vehicle body rear structure according to claim 1, wherein the rear side member is integrally formed as a light alloy casting including a bracket and a rib attached to the rear side member.