JP4657018B2

JP4657018B2 - Suspension member

Info

Publication number: JP4657018B2
Application number: JP2005173480A
Authority: JP
Inventors: 英司安在; 雄之介山田; 善裕今野; 友貴村山
Original assignee: Nissan Motor Co Ltd; Nippon Light Metal Co Ltd
Current assignee: Nissan Motor Co Ltd; Nippon Light Metal Co Ltd
Priority date: 2005-06-14
Filing date: 2005-06-14
Publication date: 2011-03-23
Anticipated expiration: 2025-06-14
Also published as: JP2006347253A

Description

この発明は、サスペンションメンバに関するもので、更に詳細には、車体側に連結され、サスペンションアームの車体側を支持すると共にエンジン等を設置する、サスペンションメンバに関するものである。 The present invention relates to a suspension member, and more particularly to a suspension member that is connected to a vehicle body side, supports the vehicle body side of a suspension arm, and installs an engine or the like.

一般に、フロントサスペンションを構成するサスペンションメンバは、車体の前後方向に延在する一対のサイドメンバと、両サイドメンバに連結されるクロスメンバとを具備しており、サイドメンバにはサスペンションアームの車体側を支持する支持部が設けられ、クロスメンバの一部には、エンジンやステアリング装置等が搭載されている。 In general, the suspension member constituting the front suspension includes a pair of side members extending in the front-rear direction of the vehicle body and a cross member connected to both side members. Is provided, and an engine, a steering device, and the like are mounted on a part of the cross member.

また、この種のサスペンションメンバには、軽量化の観点からアルミニウム合金製の一体鋳造品によって形成されるものが使用されている。 In addition, as this type of suspension member, a member formed by an integrally cast product made of an aluminum alloy is used from the viewpoint of weight reduction.

このアルミニウム合金製サスペンションメンバにはサスペンションアームやスタビライザ等を介して走行時大きな外力の入力があるため、その剛性及び強度をもたせるために、サイドメンバの内方側壁に、サスペンションアームを枢着する支持部からの距離に応じて車幅方向の幅が増大する補強フランジを設けた構造のものが知られている（例えば、特許文献１参照）。 Since this aluminum alloy suspension member has a large external force input during travel through the suspension arm, stabilizer, etc., in order to give its rigidity and strength, the suspension arm is pivotally attached to the inner side wall of the side member. The thing of the structure which provided the reinforcement flange which the width | variety of a vehicle width direction increases according to the distance from a part is known (for example, refer patent document 1).

また、サスペンションメンバとしてエンジンをクロスメンバとその前方に配置させたエンジンサポートメンバにより固定したものが知られており、クロスメンバによってエンジンサポートメンバを固定すると共に、エンジンサポートメンバの前方部に切欠き部を形成し、衝突時にはこの切欠き部でエンジンサポートメンバを下方に変形し、エンジンを下方に変位させることによりエンジンの後方への変位を防止するようにした構造のものも知られている（例えば、特許文献２参照）。
特許第３１７５５２３号公報（特許請求の範囲、図１，図３）実開平５−７８６７１号公報（実用新案登録請求の範囲、段落番号００１１，００１２、図１，図２） A suspension member is known in which an engine is fixed by a cross member and an engine support member disposed in front of the cross member. The engine support member is fixed by the cross member, and a notch is formed in the front portion of the engine support member. There is also known a structure in which the engine support member is deformed downward at the notch in the event of a collision and the engine is displaced downward to prevent the engine from being displaced backward (for example, , See Patent Document 2).
Japanese Patent No. 3175523 (Claims, FIGS. 1 and 3) Japanese Utility Model Laid-Open No. 5-78671 (claims for utility model registration, paragraph numbers 0011, 0012, FIGS. 1 and 2)

しかしながら、前者すなわち特許第３１７５５２３号公報に記載の構造のものは、サスペンションメンバをアルミニウム合金製の一体鋳造品にて形成するに際し、小型化とサスペンションアームよりの外力に対する強度保持についての提案はあるが、逆にサスペンションメンバの全体強度が増加したことによる、衝突エネルギのコントロールに関しての開示はされていない。 However, the former, that is, the structure described in Japanese Patent No. 3175523, has proposals for downsizing and maintaining strength against external force from the suspension arm when the suspension member is formed of an aluminum alloy integrally cast product. On the contrary, there is no disclosure regarding the control of the collision energy due to the increase in the overall strength of the suspension member.

また、サスペンションアームには常時大きな外力が加わり頑強に形成されている為に、サスペンションメンバに前方より後方に向かう大きな衝突エネルギが加わった場合、サスペンションアームが車内側に移動しないようにする工夫が必要とされた。 In addition, since the suspension arm is always strong with a large external force applied, it must be devised to prevent the suspension arm from moving to the vehicle interior when a large collision energy is applied to the suspension member from the front to the rear. It was said.

一方、後者すなわち実開平５−７８６７１号公報に記載の構造のものにおいては、サイドメンバとクロスメンバの他に、エンジンを支持するエンジンサポートメンバと、このエンジンサポートメンバの固定部を補強する補強部材とを具備するために、構成部材が多くなると共に、重量が嵩み、かつ、組立が面倒な上、コストが嵩む等の問題があった。また、実開平５−７８６７１号公報に記載の構造のものは、エンジンサポートメンバの前方部に設けられた切欠き部によって衝突時のエンジンサポートメンバを下方に変形させ、エンジンを下方に変位することが可能であり、衝突に際してエンジンの後方への移動を避けることの開示はなされているが衝突エネルギの伝達についての開示はなされていない。 On the other hand, in the latter structure, that is, the structure described in Japanese Utility Model Laid-Open No. 5-78671, in addition to the side member and the cross member, an engine support member that supports the engine and a reinforcing member that reinforces the fixing portion of the engine support member. Therefore, there are problems that the number of components increases, the weight increases, the assembly is troublesome, and the cost increases. Further, in the structure described in Japanese Utility Model Publication No. 5-78671, the engine support member at the time of a collision is deformed downward by a notch provided in the front portion of the engine support member, and the engine is displaced downward. Although it is disclosed that the rearward movement of the engine is avoided in the event of a collision, there is no disclosure of transmission of collision energy.

一方、自動車の衝突時に衝撃エネルギは車体（サイドフレームが変形することによりによりエネルギを吸収）で吸収し、乗員に加わる衝撃力を削減するように一般に設計されているが、上記のとおり、サスペンションメンバにおけるサスペンションアームが固定される部分は走行時大きな外力が加わるために強度が大きく設計されており、この部分とサスペンションアームが一体となって剛性の高い部分を形成することになり、この部分において衝突エネルギが予定通り吸収することが困難となり何等かの、衝突エネルギのコントロール方法の工夫が課題であった。 On the other hand, the impact energy is absorbed by the vehicle body (the energy is absorbed by the deformation of the side frame) at the time of a car collision, and is generally designed to reduce the impact force applied to the occupant. The part where the suspension arm is fixed is designed to be strong because a large external force is applied during driving, and this part and the suspension arm are integrated to form a highly rigid part. It became difficult to absorb the energy as planned, and there was a problem of how to control the collision energy.

この発明は上記事情に鑑みてなされたもので、衝突時の多大な衝突エネルギの適切なエネルギのコントロールが図れることのできるサスペンションメンバを提供することを目的とする。 The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a suspension member that can appropriately control a large amount of collision energy at the time of collision.

上記目的を達成するために、この発明は、車体の前後方向に延在する一対のサイドメンバと、両サイドメンバを連結するクロスメンバとよりなり、上記サイドメンバにおける車室側の端部に車体への連結部を形成する車室側連結部を設けると共に、この車室側連結部に対して車室と逆の部位に１つあるいは２つ以上のサスペンションアーム支持部を設けたサスペンションメンバを前提とし、請求項１記載の発明は、上記サイドメンバを、車室側が低位置となるように車体の前後方向に略クランク状に形成し、低位置側に上記車室側連結部を設けると共に、上記サイドメンバにおける上記車室側連結部と該車室側連結部との距離が最も小さいサスペンションアーム支持部との間に、破断誘起部を形成してなり、上記サイドメンバは、少なくとも上記破断誘起部の領域を含む前後方向における表面部の裏面にサイドメンバに沿う補強リブを突設してなり、上記補強リブの先端部に、上記破断誘起部を形成する段部を設けた、ことを特徴とする。 In order to achieve the above object, the present invention comprises a pair of side members extending in the front-rear direction of a vehicle body and a cross member connecting both side members. It is assumed that the suspension member is provided with a vehicle compartment side connection portion that forms a connection portion to the vehicle compartment, and that one or more suspension arm support portions are provided on the opposite side of the vehicle compartment with respect to the vehicle compartment side connection portion. In the first aspect of the invention, the side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the passenger compartment side is at a low position, and the passenger compartment side connecting portion is provided on the lower position side. between the distance is smallest suspension arm support between the cabin-side connecting portion and該車chamber side connecting portion in the side members, it forms a fracture inducing portion, the side members are reduced when It was projected reinforcing ribs along the side member on the rear surface of the surface portion in the longitudinal direction including the region of the fracture inducing portion, the distal end portion of the reinforcing ribs, is provided a stepped portion for forming the fracture inducing portion, It is characterized by that.

このように構成することにより、サスペンションアームを支持するために基より強度が増強されると共にサスペンションアームの強度と相俟って高い剛性で形成されるサスペンションメンバのサスペンションアーム支持部分は、一定以上の衝突エネルギが負荷された際に、最も車室側に近いサスペンションアーム支持部と車体との連結部である車室側連結部との間で破断されることになる。 With this configuration, the suspension arm support portion of the suspension member, which has a strength higher than the base for supporting the suspension arm and is formed with high rigidity in combination with the strength of the suspension arm, exceeds a certain level. When the collision energy is loaded, the vehicle breaks between the suspension arm support portion closest to the vehicle compartment side and the vehicle compartment side connection portion that is the connection portion of the vehicle body.

これにより、サスペンションメンバのサスペンションアームの支持部分を介して衝突エネルギが車内に直接伝達されることがなくなり、衝突エネルギは車体本体（サイドフレーム）にてスムーズに吸収される。 As a result, the collision energy is not directly transmitted into the vehicle via the suspension arm support portion of the suspension member, and the collision energy is smoothly absorbed by the vehicle body (side frame).

またこのように構成することにより、補強リブにより通常走行時にはサスペンションメンバに必要な強度を維持し、衝突等によって前方又は後方からの許容以上の衝撃力を受けた際に、段部に応力集中が生じるので、破断誘起部が確実に破断する。 In addition, with this configuration, the strength required for the suspension member is maintained by the reinforcing rib during normal driving, and stress concentration is applied to the stepped portion when an impact force exceeding the allowable value from the front or the rear is received due to a collision or the like. As a result, the fracture inducing portion is reliably fractured.

また、請求項２記載の発明は、上記サイドメンバを、車室側が低位置となるように車体の前後方向に略クランク状に形成し、低位置側に上記車室側連結部を設けると共に、上記サイドメンバにおける上記車室側連結部と該車室側連結部との距離が最も小さいサスペンションアーム支持部との間に、破断誘起部を形成してなり、上記サイドメンバは、少なくとも破断誘起部の領域を含む前後方向における表面部の裏面にサイドメンバに沿う補強リブを突設してなり、上記破断誘起部の領域に位置する補強リブの肉厚を、破断誘起部の前後で変化させてなる、ことを特徴とする。 According to a second aspect of the present invention, the side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the passenger compartment side is at a low position, and the passenger compartment side connecting portion is provided on the lower position side. A rupture inducing portion is formed between the passenger compartment side connecting portion of the side member and the suspension arm support portion having the smallest distance between the passenger compartment side connecting portion, and the side member has at least a rupture inducing portion. A reinforcing rib extending along the side member is provided on the back surface of the front surface portion in the front-rear direction including the region, and the thickness of the reinforcing rib located in the region of the fracture inducing portion is changed before and after the fracture inducing portion. It is characterized by.

このように構成することにより、衝突等によって前方又は後方からの許容以上の衝撃力を受けた際に、補強リブの板厚変化部に応力集中が生じ破断誘起部となるので、板厚変化部が確実に破断する。 By configuring in this way, when an impact force exceeding an allowable value from the front or the rear is received due to a collision or the like, stress concentration occurs in the thickness change portion of the reinforcing rib, resulting in a fracture inducing portion. Breaks reliably.

また、請求項３記載の発明は、上記サイドメンバを、車室側が低位置となるように車体の前後方向に略クランク状に形成し、低位置側に上記車室側連結部を設けると共に、上記サイドメンバにおける上記車室側連結部と該車室側連結部との距離が最も小さいサスペンションアーム支持部との間に、破断誘起部を形成してなり、上記サイドメンバは、少なくとも破断誘起部の領域を含む前後方向における表面部の裏面にサイドメンバに沿う補強リブを突設してなり、上記補強リブの先端部に、上記破断誘起部を形成する切欠きを設けた、ことを特徴とする。 According to a third aspect of the present invention, the side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the passenger compartment side is at a low position, and the passenger compartment side connecting portion is provided on the lower position side. A rupture inducing portion is formed between the passenger compartment side connecting portion of the side member and the suspension arm support portion having the smallest distance between the passenger compartment side connecting portion, and the side member has at least a rupture inducing portion. A reinforcing rib extending along the side member is provided on the back surface of the front surface portion in the front-rear direction including the region, and a notch for forming the fracture inducing portion is provided at the front end portion of the reinforcing rib. To do.

このように構成することにより、衝突等によって前方又は後方からの許容以上の衝撃力を受けた際に、切欠きに応力集中が生じるので、許容以上の力によって破断誘起部が確実に破断する。 With this configuration, when an impact force exceeding the allowable value from the front or the rear is received due to a collision or the like, stress concentration occurs in the notch, so that the breakage inducing portion is reliably broken by the excessive force.

また、請求項４記載の発明は、上記サイドメンバを、車室側が低位置となるように車体の前後方向に略クランク状に形成し、低位置側に上記車室側連結部を設けると共に、上記サイドメンバにおける上記車室側連結部と該車室側連結部との距離が最も小さいサスペンションアーム支持部との間に、破断誘起部を形成してなり、上記サイドメンバにおける車室側連結部とサスペンションアーム支持部のうち車室側連結部との距離が最も小さいサスペンションアーム支持部との間に熱処理により破断誘起部となる強度低下部を形成してなる、ことを特徴とする。 According to a fourth aspect of the present invention, the side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the passenger compartment side is at a low position, and the passenger compartment side connecting portion is provided on the lower position side. A breakage induction portion is formed between the vehicle compartment side connection portion of the side member and the suspension arm support portion having the smallest distance between the vehicle compartment side connection portion, and the vehicle compartment side connection portion of the side member. And a suspension arm support portion of the suspension arm support portion having the smallest distance from the vehicle compartment side connection portion, a strength reduction portion that becomes a fracture inducing portion is formed by heat treatment.

このように構成することにより、衝突等によって前方又は後方からの許容以上の衝撃力を受けた際に、上記サイドメンバにおける車室側連結部とサスペンションアーム支持部のうち車室側連結部との距離が最も小さいサスペンションアーム支持部との間に熱処理による強度低下部により破断誘起部が形成されるので衝撃力が許容以上になると破断され上記目的を達成する。 By configuring in this way, when receiving an impact force exceeding the allowable value from the front or the rear due to a collision or the like, the vehicle compartment side connection portion of the side member and the vehicle compartment side connection portion of the suspension arm support portion Since the fracture inducing portion is formed by the strength-decreasing portion due to the heat treatment between the suspension arm support portion having the smallest distance, the fracture is achieved when the impact force exceeds an allowable value, and the above-described object is achieved.

なお、サイドメンバの車室側連結部とサスペンションアーム支持部のうち車室側連結部との距離が最も小さいサスペンションアーム支持部との間には、請求項１から３記載の発明と同様に補強リブを形成しておき、この補強リブに熱処理による強度低下部を形成してもよい。なお、熱処理としては加熱により強度低下を施す熱影響を与える既知の処理方法を施せばよい。 It should be noted that the reinforcement between the side member's compartment-side connecting portion and the suspension arm support portion having the smallest distance between the compartment-side connecting portion and the suspension arm support portion is the same as in the first to third aspects of the invention. A rib may be formed in advance, and a strength reduction portion by heat treatment may be formed on the reinforcing rib. In addition, what is necessary is just to give the known processing method which gives the thermal influence which reduces intensity | strength by heating as heat processing.

また、請求項５記載の発明は、上記サイドメンバを、車室側が低位置となるように車体の前後方向に略クランク状に形成し、低位置側に上記車室側連結部を設けると共に、上記サイドメンバにおける上記車室側連結部と該車室側連結部との距離が最も小さいサスペンションアーム支持部との間に、破断誘起部を形成してなり、上記サイドメンバは、少なくとも破断誘起部の領域を含む前後方向における表面部の裏面にサイドメンバに沿う補強リブを突設してなり、上記破断誘起部の領域に位置する補強リブの高さを、破断誘起部の前後で変化させてなる、ことを特徴とする。 According to a fifth aspect of the present invention, the side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the passenger compartment side is at a low position, and the passenger compartment side connecting portion is provided on the lower position side. A rupture inducing portion is formed between the passenger compartment side connecting portion of the side member and the suspension arm support portion having the smallest distance between the passenger compartment side connecting portion, and the side member has at least a rupture inducing portion. A reinforcing rib is provided along the side member on the back surface of the front surface portion in the front-rear direction including the region, and the height of the reinforcing rib located in the region of the breakage induction portion is changed before and after the breakage induction portion. It is characterized by.

このように構成することにより、衝突等によって前方又は後方からの許容以上の衝撃力を受けた際に、補強リブの高さが変化するので応力集中が生じやすくなり、許容以上の力によって破断誘起部が確実に破断する。 With this configuration, when an impact force exceeding the allowable value from the front or the rear is received due to a collision or the like, the height of the reinforcing rib changes, so stress concentration is likely to occur. The part breaks reliably.

また、請求項６記載の発明は、上記サイドメンバを、車室側が低位置となるように車体の前後方向に略クランク状に形成し、低位置側に上記車室側連結部を設けると共に、上記サイドメンバにおける上記車室側連結部と該車室側連結部との距離が最も小さいサスペンションアーム支持部との間に、破断誘起部を形成してなり、上記サイドメンバは、少なくとも破断誘起部の領域を含む前後方向における表面部の裏面にサイドメンバに沿う補強リブを突設してなり、上記破断誘起部の領域に位置する補強リブの高さ及び板厚を、破断誘起部の前後で変化させてなる、ことを特徴とする。 The invention of claim 6 is the side members, with the passenger compartment side is formed in a substantially crank shape in the longitudinal direction of the vehicle body so that the low position, providing the cabin-side connecting portion to the low position side, A rupture inducing portion is formed between the passenger compartment side connecting portion of the side member and the suspension arm support portion having the smallest distance between the passenger compartment side connecting portion, and the side member has at least a rupture inducing portion. Reinforcing ribs extending along the side members are provided on the back surface of the front surface portion in the front-rear direction including the region, and the height and thickness of the reinforcing ribs located in the region of the breakage induction portion are determined before and after the breakage induction portion. It is characterized by being changed.

このように構成することにより、衝突等によって前方又は後方からの許容以上の衝撃力を受けた際に、補強リブの高さと板厚が変化するので応力集中が生じやすくなり、許容以上の力によって破断誘起部が確実に破断する。 By configuring in this way, when an impact force exceeding the allowable value from the front or the rear is received due to a collision or the like, the height and thickness of the reinforcing rib change, so stress concentration is likely to occur. The rupture-inducing part is reliably broken.

また、請求項１〜６記載の発明によれば、衝突等によって前方又は後方からの衝撃力を受けると、車室側連結部を支点として下方側に向かうモーメントが生じ、破断誘起部が破断した際に、サイドメンバが確実に下方に変位される。これにより、サスペンションメンバのサスペンションアームが固定される部分であるために強度が大きく形成されるとともにサスペンションアーム自体の強度と合わさり増強された部分が、衝突事故の際に車室側に移動することがない。また、エンジンも少なくとも車室側部がサスペンションメンバに支持されているので、衝突時に車室側に移動することがなく下方に変位させることができる。 According to the invention of claim 6, wherein, when receiving an impact force from the front or rear by a collision or the like, a moment directed downward side as a fulcrum cabin side connecting portion occurs, rupture inducing portion is broken At this time, the side member is reliably displaced downward. As a result, since the suspension member of the suspension member is a portion to which the suspension arm is fixed, the strength of the suspension member is increased and the strength of the suspension arm itself is increased to move toward the passenger compartment in the event of a collision. Absent. Further, since at least the compartment side of the engine is supported by the suspension member, the engine can be displaced downward without moving to the compartment side in the event of a collision.

加えて、請求項７記載の発明は、請求項１ないし６のいずれかに記載のサスペンションメンバにおいて、上記サスペンションメンバの材質がアルミニウム合金であることを特徴とする。 According to a seventh aspect of the present invention, in the suspension member according to any one of the first to sixth aspects, the material of the suspension member is an aluminum alloy.

このように構成することにより、サスペンションメンバ自体を軽量にすることができる。 With this configuration, the suspension member itself can be reduced in weight.

この発明によれば、上記のように構成されているので、以下のような優れた効果が得られる。 According to this invention, since it is configured as described above, the following excellent effects can be obtained.

（１）請求項１〜６記載の発明によれば、衝突等によって前方又は後方からの衝撃力を受けた際に、破断誘起部に応力集中が生じ、衝撃力が許容限度以上に達すると破断誘起部が破断するので、衝突時に大きな衝突エネルギが負荷された際に、この衝突エネルギがサスペンションメンバを介して直接車内に伝わることがなく車体（サイドフレーム）にて適切に吸収されて伝えられることになる。 (1) According to the inventions of claims 1 to 6 , when an impact force from the front or the rear is received due to a collision or the like, stress concentration occurs in the fracture inducing portion, and the fracture occurs when the impact force exceeds an allowable limit. Since the induction part breaks, when a large collision energy is loaded at the time of a collision, the collision energy is not directly transmitted to the inside of the vehicle via the suspension member, but is appropriately absorbed and transmitted by the vehicle body (side frame). become.

（２）また、請求項１〜６記載の発明によれば、衝突等によって前方又は後方からの衝撃力を受けると、車室側連結部を支点として下方側に向かうモーメントが生じ、破断誘起部が破断した際に、サイドメンバ及びサスペンションフレームを確実に下方に変位させることができるので車室側への移動が生じない。 (2) Moreover, according to invention of Claims 1-6, when the impact force from the front or back is received by a collision etc., the moment which goes below using a vehicle compartment side connection part as a fulcrum will arise, and a fracture | rupture induction part When the rupture breaks, the side member and the suspension frame can be reliably displaced downward, so that no movement toward the passenger compartment side occurs.

（３）請求項７記載の発明によれば、サスペンションメンバの材質をアルミニウム合金とすることにより、サスペンションメンバ自体を軽量にすることができるので、上記（１），（２）に加えて、更に軽量化を図ることができる。 (3) According to the seventh aspect of the present invention, by the material of the suspension member with the aluminum alloy, since the suspension member itself can be made lighter, the (1), in addition to (2), further Weight reduction can be achieved.

以下に、この発明の最良の実施形態をフロントサスペンションメンバに利用した例を示す添付図面に基づいて詳細に説明する。 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best embodiment of the present invention will be described in detail with reference to the accompanying drawings showing an example in which a front suspension member is used.

図１は、この発明に係るアルミニウム合金製サスペンションメンバの平面図、図２は、図１の側面図、図３は、図１の底面図、図４は、この発明におけるサイドメンバの後端部と車体との連結部及びサスペンションアームのロアアームの支持部を示す底面斜視図、図５は、図４の拡大側面図である。 1 is a plan view of an aluminum alloy suspension member according to the present invention, FIG. 2 is a side view of FIG. 1, FIG. 3 is a bottom view of FIG. 1, and FIG. FIG. 5 is an enlarged side view of FIG. 4. FIG. 5 is a bottom perspective view showing a connecting portion between the vehicle and the vehicle body and a lower arm support portion of the suspension arm.

上記サスペンションメンバ１は、図１ないし図３に示すように、車体の前後方向に延在する一対のサイドメンバ１１と、両サイドメンバ１１の中間部を連結するセンタクロスメンバ１２及び両サイドメンバ１１の後端側を連結するリアクロスメンバ１３とを一体に形成したアルミニウム合金製の鋳造品によって形成されるサスペンションメンバ本体１０と、両サイドメンバ１１の車体前方側の先端部に連結されて車体の前後方向に延在するアルミニウム合金製押出形材で形成される補助サイドメンバ１５と、その先端部に架設されるファーストクロスメンバ１４とで主に構成されている。なお、サスペンションメンバ本体１０において、サイドメンバ１１とセンタクロスメンバ１２及びリアクロスメンバ１３との連結部は応力集中を避けるように円弧状に形成されている。 As shown in FIGS. 1 to 3, the suspension member 1 includes a pair of side members 11 extending in the front-rear direction of the vehicle body, a center cross member 12 that connects intermediate portions of both side members 11, and both side members 11. A suspension member main body 10 formed of an aluminum alloy casting integrally formed with a rear cross member 13 that connects the rear end side of the vehicle and a front end portion of the side members 11 on the front side of the vehicle body. It is mainly composed of an auxiliary side member 15 formed of an aluminum alloy extruded profile extending in the front-rear direction and a first cross member 14 installed at the tip of the auxiliary side member 15. In the suspension member main body 10, the connecting portions of the side member 11, the center cross member 12, and the rear cross member 13 are formed in an arc shape so as to avoid stress concentration.

補助サイドメンバ１５をサスペンションメンバ本体１０と別体に形成した理由は、複雑な形状となる本体部を鋳造成形し、単純な形状となる部分を別体の押出成形とし製造容易にしたことと、軽微な衝突に際し、補助サイドメンバ１５により一定の範囲まで車体（サイドフレーム）と共に定常的にエネルギを吸収させることで、サスペンションメンバ本体１０と、これに搭載されている駆動，操舵，制動装置等に影響を与えないようにするためである。 The reason why the auxiliary side member 15 is formed separately from the suspension member main body 10 is that the main body portion having a complicated shape is cast-molded, and the simple shape portion is formed by separate extrusion molding to facilitate manufacture. In the event of a minor collision, the auxiliary side member 15 steadily absorbs energy together with the vehicle body (side frame) to a certain range, so that the suspension member main body 10 and the drive, steering, braking device and the like mounted thereon can be This is to prevent the influence.

上記サイドメンバ１１には、車体の前後方向の後端部と中間部よりやや先端側部に、車体のサイドフレーム２への連結部１６，１７（以下に車室側連結部１６，中間連結部１７という）が設けられている。 The side member 11 includes connecting portions 16 and 17 (hereinafter referred to as a vehicle compartment side connecting portion 16 and an intermediate connecting portion) connected to the side frame 2 of the vehicle body at a slightly distal end side portion from a rear end portion and an intermediate portion in the longitudinal direction of the vehicle body. 17).

また、車室側連結部１６の車体の前方向側部位には、サスペンションアームを構成するロアアーム３の後端側アーム片３ａの支持部２１（以下に第１の支持部２１という）が設けられる。更に、車室側連結部１６と第１の支持部２１との間には、前方からの衝撃力を受けた際に、応力集中が生じ破断する破断誘起部２０が設けられている。また、サイドメンバ１１の中間部には、ロアアーム３の先端側アーム片３ｂの支持部２２（以下に第２の支持部２２という）が設けられている。 Further, a support portion 21 (hereinafter referred to as a first support portion 21) of the rear end side arm piece 3a of the lower arm 3 constituting the suspension arm is provided at a front side portion of the vehicle body side connecting portion 16 in the vehicle body. . Further, a breakage inducing portion 20 is provided between the passenger compartment side connecting portion 16 and the first support portion 21, and when stress is applied from the front, stress concentration occurs and breaks. Further, a support portion 22 (hereinafter referred to as a second support portion 22) of the distal end side arm piece 3 b of the lower arm 3 is provided in an intermediate portion of the side member 11.

また、サイドメンバ１１は、表面部１１ａの両側辺に側壁１１ｂを垂下した断面略逆Ｕ字状に形成されると共に、少なくとも破断誘起部２０の領域を含む前後方向における表面部１１ａの裏面にサイドメンバ１１に沿う補強リブ３０が突設されている。なお、図３に示すように、車室側連結部１６及び中間連結部１７を構成する連結孔１６ａ，１７ａを有するボス１６ｂ，１７ｂにはそれぞれ補強リブ３０が連設されて、強度の補強が図られており、通常の走行時に必要なサスペンションメンバ１の強度が維持されている。また、第１の支持部２１を構成する取付孔２１ａを有する２つのボス２１ｂにもそれぞれ補強リブ３０が連設されて、強度の補強が図られている（図３参照）。なお、側壁１１ｂもサイドメンバ１１を補強する補強リブである。 Further, the side member 11 is formed in a substantially inverted U-shaped cross-section with a side wall 11b suspended from both sides of the surface portion 11a, and at the side of the back surface of the surface portion 11a in the front-rear direction including at least the region of the breakage inducing portion 20. Reinforcing ribs 30 are projected along the member 11. As shown in FIG. 3, reinforcing ribs 30 are connected to the bosses 16b and 17b having the connecting holes 16a and 17a constituting the passenger compartment side connecting portion 16 and the intermediate connecting portion 17, respectively, to strengthen the strength. As shown, the strength of the suspension member 1 required during normal travel is maintained. In addition, reinforcing ribs 30 are also provided on the two bosses 21b having the mounting holes 21a constituting the first support portion 21 to reinforce the strength (see FIG. 3). The side wall 11b is also a reinforcing rib that reinforces the side member 11.

上記第２の支持部２２は、車体の前後方向に対峙する前方側ブラケット２２ａと後方側ブラケット２２ｂとで構成されており、前方側ブラケット２２ａの前方側及び後方側ブラケット２２ｂの後方側には、それぞれ補強リブ２３ａ，２３ｂが連設されている（図２及び図３参照）。この場合、両ブラケット２２ａ，２２ｂはサイドメンバ１１の側壁１１ｂに連設されており、両ブラケット２２ａ，２２ｂ間における側壁１１ｂは、後方から前方に向かって高さが漸次低くなるようにカットされている。また、前方側ブラケット２２ａに連設する補強リブ２３ａの高さを後方側ブラケット２２ｂに連設する補強リブ２３ｂに対して低く形成してある。このように形成することにより、前方側ブラケット２２ａに若干の可撓性をもたせ、後方側ブラケット２２ｂに剛性をもたせている。すなわち、第２の支持部２２にロアアーム３の先端側アーム片３ｂを取り付ける際、ブッシュを装着した先端側アーム片３ｂを両ブラケット２２ａ，２２ｂ間に挿入し、両ブラケット２２ａ，２２ｂ及び先端側アーム片３ｂを貫通するボルト２４にナット２５を螺合すると、前方側ブラケット２２ａが撓んで先端側アーム片３ｂを強固に締結することができる。また、ロアアーム３からの力や前方からの力に対して後方側ブラケット２２ｂが剛性を有する。 The second support portion 22 includes a front side bracket 22a and a rear side bracket 22b that face each other in the front-rear direction of the vehicle body, and on the front side of the front side bracket 22a and the rear side of the rear side bracket 22b, Reinforcing ribs 23a and 23b are connected to each other (see FIGS. 2 and 3). In this case, the brackets 22a and 22b are connected to the side wall 11b of the side member 11, and the side wall 11b between the brackets 22a and 22b is cut so that the height gradually decreases from the rear toward the front. Yes. Moreover, the height of the reinforcing rib 23a provided continuously with the front bracket 22a is formed lower than the reinforcing rib 23b provided continuously with the rear bracket 22b. By forming in this way, the front bracket 22a has some flexibility, and the rear bracket 22b has rigidity. That is, when attaching the tip side arm piece 3b of the lower arm 3 to the second support portion 22, the tip side arm piece 3b fitted with a bush is inserted between the brackets 22a and 22b, and both the brackets 22a and 22b and the tip side arm are inserted. When the nut 25 is screwed into the bolt 24 penetrating the piece 3b, the front bracket 22a is bent and the distal end side arm piece 3b can be firmly fastened. Further, the rear side bracket 22b has rigidity against the force from the lower arm 3 and the force from the front.

更に、サイドメンバ１１は、図２に示すように、車体後方側（車室側）が低位置となるように車体の前後方向に略クランク状に形成されると共に、低位置側に車室側連結部１６及び破断誘起部２０が設けられている。この場合、サイドメンバ１１のクランク状の段差部１１ｃは、曲面状に形成され、また、平面視において、サイドメンバ１１のセンタクロスメンバ１２の取付け位置からリアクロスメンバ１３の取付け位置に向けて後端側が互いに近接する方向に傾斜して設けられると共に、後端部から車室側連結部１６に向けて互いに離反する方向に向かって広がっている（図１，図３参照）。この車室側連結部１６の連結孔１６ａを貫通するボルト，ナット等の固定部材（図示せず）によってサスペンションメンバ１はサイドフレーム２に連結されている。また、車室側連結部１６の前方側近傍位置に第１の支持部２１の取付孔２１ａが設けられ、車室側連結部１６と第１の支持部２１との間の補強リブ３０と側壁１１ｂに上記破断誘起部２０が形成されている。 Further, as shown in FIG. 2, the side member 11 is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the vehicle body rear side (vehicle compartment side) is at a low position, and the vehicle compartment side on the low position side. A connecting portion 16 and a fracture inducing portion 20 are provided. In this case, the crank-shaped step portion 11c of the side member 11 is formed in a curved surface, and is rearward from the mounting position of the center cross member 12 of the side member 11 toward the mounting position of the rear cross member 13 in plan view. The end sides are provided so as to incline in directions close to each other, and spread from the rear end portion toward the vehicle compartment side connecting portion 16 in directions away from each other (see FIGS. 1 and 3). The suspension member 1 is connected to the side frame 2 by fixing members (not shown) such as bolts and nuts that pass through the connection hole 16a of the vehicle interior side connection portion 16. Further, a mounting hole 21a of the first support portion 21 is provided at a position in the vicinity of the front side of the passenger compartment side connecting portion 16, and the reinforcing rib 30 and the side wall between the passenger compartment side connecting portion 16 and the first support portion 21 are provided. The fracture inducing portion 20 is formed on 11b.

また、サイドメンバ１１の車室側連結部１６から取付孔２１ａ、２１ａに向けて２つの補強リブ３０が、サイドメンバ１１の後端側から前方端に向かって拡開テーパ状にそれぞれ設けられており、各補強リブ３０の先端部には破断誘起部２０となる段部２０Ａが設けられている。 Further, two reinforcing ribs 30 are provided in an expanding taper shape from the rear end side to the front end of the side member 11 from the passenger compartment side connecting portion 16 of the side member 11 toward the mounting holes 21a and 21a. In addition, a step portion 20 </ b> A serving as the fracture inducing portion 20 is provided at the tip of each reinforcing rib 30.

なお、上記破断誘起部２０は、図６に示すように、サイドメンバ１１のクランク部から車室側連結部１６に渡って設けられる側壁１１ｂの先端部に設けられた段部２０Ａによっても形成されている。 As shown in FIG. 6, the breakage inducing portion 20 is also formed by a step portion 20 </ b> A provided at the front end portion of the side wall 11 b provided from the crank portion of the side member 11 to the vehicle compartment side connecting portion 16. ing.

したがって、衝突により前方からの衝撃力が作用すると、破断誘起部２０すなわち段部２０Ａに応力集中が生じ、衝撃力が許容限度以上に達すると、段部２０Ａに亀裂が生じ、その後破断誘起部２０が破断されるようになっている（図８（ａ），（ｂ）参照）。なお、本実施態様にあっては、サイドメンバ１１における破断誘起部２０の断面と、破断誘起部２０より前方側の断面は、サイドメンバ１１の表面部を平坦状にして概略的に図示すると、図６（ａ），（ｂ）に示すような断面となっており、破断誘起部２０の後方における側壁１１ｂないし補強リブ３０の高さＨ１，補強リブ３０の板厚Ｔ１，と破断誘起部２０より前方側の断面における補強リブ３０の高さＨ２，補強リブ３０の板厚Ｔ２はＨ１＜Ｈ２，Ｔ１＜Ｔ２であり補強リブ３０の高さと厚さが変化するので応力集中が生じやすく、破断誘起部２０において確実に破断される。 Therefore, when an impact force from the front acts due to a collision, stress concentration occurs in the fracture inducing portion 20, that is, the step portion 20A, and when the impact force reaches an allowable limit or more, a crack occurs in the step portion 20A, and then the fracture inducing portion 20 Is torn (see FIGS. 8A and 8B). In this embodiment, the cross section of the breakage inducing portion 20 in the side member 11 and the cross section in front of the breakage inducing portion 20 are schematically illustrated with the surface portion of the side member 11 being flat. 6 (a) and 6 (b), the side wall 11b or the height H1 of the reinforcing rib 30 at the rear of the fracture inducing portion 20, the plate thickness T1 of the reinforcing rib 30, and the fracture inducing portion 20 are shown. The height H2 of the reinforcing rib 30 and the plate thickness T2 of the reinforcing rib 30 in the cross section on the front side are H1 <H2 and T1 <T2, and the height and thickness of the reinforcing rib 30 change. The induction part 20 is reliably broken.

なお、本実施態様にあっては、補強リブ３０の高さと板厚共に、破断誘起部２０の前後で変化させたが、いずれか一方でもよい。また、補強リブ３０の高さをＨ１＜Ｈ２としたが、Ｈ１＞Ｈ２としても高さの変化部で応力集中を生じ、破断誘起２０を構成することができる。また、補強リブ３０の板厚についてもＴ１＞Ｔ２としてもよく、いずれにしても補強リブ３０の高さないし板厚を変化させることにより、応力集中を生じさせ破断誘起部２０での破断を誘起させればよい。 In the present embodiment, both the height and thickness of the reinforcing rib 30 are changed before and after the fracture inducing portion 20, but either one may be used. In addition, although the height of the reinforcing rib 30 is set to H1 <H2, stress concentration occurs at the height change portion even when H1> H2, and the fracture induction 20 can be configured. Further, the thickness of the reinforcing rib 30 may be T1> T2, and in any case, by changing the thickness of the reinforcing rib 30 or changing the thickness, stress concentration is caused to induce breakage at the breakage inducing portion 20. You can do it.

これらの破断誘起部２０は補強リブ３０の他、補強リブを構成する側壁１１ｂの双方に形成してもよいし、その何れかに形成することもできる。 These breakage inducing portions 20 may be formed on both of the side walls 11b constituting the reinforcing ribs in addition to the reinforcing ribs 30, or may be formed on either of them.

また、破断誘起部２０の幅Ｗ１に対して、破断誘起部２０より前方側の断面におけるサイドメンバ１１の幅Ｗ２はＷ１＜Ｗ２であるので、サイドメンバ１１における破断誘起部２０の断面積は、破断誘起部２０より前方側の断面積より小さくなり、破断誘起部２０で確実に破断される。 Further, since the width W2 of the side member 11 in the cross section in front of the fracture inducing portion 20 is W1 <W2 with respect to the width W1 of the fracture inducing portion 20, the cross-sectional area of the fracture inducing portion 20 in the side member 11 is It becomes smaller than the cross-sectional area on the front side than the breakage inducing part 20, and the breakage inducing part 20 is reliably broken.

上記センタクロスメンバ１２の左右両側には、エンジン４を固定するための取付孔１２ａが設けられており、これら取付孔１２ａを貫通する取付ボルト等の締結部材（図示せず）介してエンジン４の後端部が固定されるようになっている。なお、エンジン４の前方側はサイドフレーム２に固定される。 Mounting holes 12a for fixing the engine 4 are provided on both the left and right sides of the center cross member 12, and the engine 4 is connected via fastening members (not shown) such as mounting bolts that pass through the mounting holes 12a. The rear end is fixed. The front side of the engine 4 is fixed to the side frame 2.

なお、サイドメンバ１１の先端側の対向する内面には、スタビライザ６を取り付けるブラケット１９が突設されている。また、リアクロスメンバ１３に一端部が取り付けられ、他端部が補剛板７を介してセンタクロスメンバ１２に取り付けられるセンターバー８を用いて、ステアリング部品（図示せず）がサスペンションメンバ１上に組み付けられるようになっている。 A bracket 19 for attaching the stabilizer 6 projects from the opposing inner surface of the side member 11 on the front end side. Further, a steering part (not shown) is mounted on the suspension member 1 by using a center bar 8 having one end attached to the rear cross member 13 and the other end attached to the center cross member 12 via the stiffening plate 7. Can be assembled to.

上記補助サイドメンバ１５は、アルミニウム合金製の断面略中空矩形状の押出形材によって形成されており、サスペンションメンバ本体１０の両サイドメンバ１１の先端部に、それぞれアングル状の取付金具４０及び取付ボルト５１，ナット５２をもって連結されている。両補助サイドメンバ１５の先端部間にはファーストクロスメンバ１４が連結されている。また、補助サイドメンバ１５の先端部には、車体のサイドフレーム２への先端連結部１８が設けられている。 The auxiliary side member 15 is formed of an extruded shape member made of an aluminum alloy and having a substantially hollow rectangular cross section. At the front ends of the side members 11 of the suspension member main body 10, angle-shaped mounting brackets 40 and mounting bolts are provided. 51 and nut 52 are connected. A first cross member 14 is connected between the tip portions of both auxiliary side members 15. Further, a distal end connecting portion 18 to the side frame 2 of the vehicle body is provided at the distal end portion of the auxiliary side member 15.

この補助サイドメンバ１５をサスペンションメンバ本体１０に取り付けるには、まず、補助サイドメンバ１５の取付側の端部内の対向する内面（上下辺）に当接するアルミニウム合金製の押出形材にて形成されるカラー６０を仮止めしておき、この補助サイドメンバ１５の端部を、断面略逆Ｕ字状のサイドメンバ１１の先端部内に挿入する。次に、取付金具４０の取付片４１を補助サイドメンバ１５の下面に当接し、下方から取付ボルト５１を取付片４１に設けられた取付孔４１ａ，補助サイドメンバ１５に設けられた貫通孔１５ａ，カラー６０に設けられた貫通孔６０ａ及びサイドメンバ１１の表面部１１ａに設けられた透孔１１ｄ内を貫通した状態で、取付ボルト５１の突出部にナット５２を締結する。この際、カラー６０が補助サイドメンバ１５の対向する内面に当接しているので、補助サイドメンバ１５は変形することがなく、サイドメンバ１１の表面部１１ａと取付片４１間に強固に挟持される。そして、取付金具４０の固定片４２に設けられた長孔４２ａを介して固定ボルト５３を上記スタビライザ６を取り付けるブラケット１９に貫通し、その突出部にナット５４を螺合して、補助サイドメンバ１５をサスペンションメンバ本体１０に連結する。 In order to attach the auxiliary side member 15 to the suspension member main body 10, first, the auxiliary side member 15 is formed of an extruded shape made of an aluminum alloy that comes into contact with the opposing inner surfaces (upper and lower sides) in the end portion on the attachment side of the auxiliary side member 15. The collar 60 is temporarily fixed, and the end portion of the auxiliary side member 15 is inserted into the front end portion of the side member 11 having a substantially U-shaped cross section. Next, the mounting piece 41 of the mounting bracket 40 is brought into contact with the lower surface of the auxiliary side member 15, and the mounting bolts 51 are provided in the mounting piece 41 from below, the through holes 15a provided in the auxiliary side member 15, The nut 52 is fastened to the projecting portion of the mounting bolt 51 in a state of passing through the through hole 60 a provided in the collar 60 and the through hole 11 d provided in the surface portion 11 a of the side member 11. At this time, since the collar 60 is in contact with the opposing inner surface of the auxiliary side member 15, the auxiliary side member 15 is not deformed and is firmly held between the surface portion 11 a of the side member 11 and the mounting piece 41. . Then, the fixing bolt 53 is passed through the bracket 19 to which the stabilizer 6 is attached through the elongated hole 42a provided in the fixing piece 42 of the mounting bracket 40, and the nut 54 is screwed into the protruding portion, so that the auxiliary side member 15 is inserted. Are coupled to the suspension member main body 10.

上記のように構成されるサスペンションメンバ１は、先端連結部１８，中間連結部１７及び車室側連結部１６に図示しないボルト，ナットをもって車体のサイドフレーム２に固定され、サイドメンバ１１の第１の支持部２１及び第２の支持部２２にサスペンションアームのロアアーム３の後端側アーム片３ａ及び先端側アーム片３ｂが支持される。 The suspension member 1 configured as described above is fixed to the side frame 2 of the vehicle body with bolts and nuts (not shown) at the front end connecting portion 18, the intermediate connecting portion 17 and the vehicle interior side connecting portion 16. The rear end side arm piece 3 a and the front end side arm piece 3 b of the lower arm 3 of the suspension arm are supported by the support portion 21 and the second support portion 22.

上記サスペンションメンバ１によれば、図８（ａ），（ｂ）に示すように、衝突等によって前方から衝撃力を受けると、まず、サスペンションメンバ本体１０に比べて剛性の低い補助サイドメンバ１５が座屈変形して衝撃エネルギを吸収し、更に衝撃力が加わると、サイドメンバ１１には、車室側連結部１６を支点として下方方向の曲げモーメントが作用すると共に、破断誘起部２０すなわち段部２０Ａに応力集中が生じ、応力が許容限度以上に達すると、破断誘起部２０に亀裂が生じ、破断誘起部２０が破断される。 According to the suspension member 1, as shown in FIGS. 8A and 8B, when receiving an impact force from the front due to a collision or the like, first, the auxiliary side member 15 having a lower rigidity than the suspension member body 10 is provided. When impact energy is absorbed by buckling deformation and further impact force is applied, a downward bending moment acts on the side member 11 with the passenger compartment side connecting portion 16 as a fulcrum, and the fracture inducing portion 20 or stepped portion. When stress concentration occurs in 20A and the stress reaches an allowable limit or more, a crack is generated in the fracture inducing portion 20, and the fracture inducing portion 20 is broken.

これにより、衝突により生じる衝撃エネルギはサスペンションメンバ１を介して車内に伝わることがなくなり、衝撃エネルギは車体（サイドフレーム）を介して車内に伝わることになる。つまり、車体の座屈（サイドフレームの軸圧壊）によりエネルギをスムーズに吸収することとなる。また上記破断に伴い、サイドメンバ１１，ロアアーム３が下方に変位する。したがって、車体内にロアアーム３が移動するのを阻止することができる。 Thereby, the impact energy generated by the collision is not transmitted to the inside of the vehicle via the suspension member 1, and the impact energy is transmitted to the inside of the vehicle via the vehicle body (side frame). That is, energy is smoothly absorbed by the buckling of the vehicle body (axial collapse of the side frame). Further, along with the breakage, the side member 11 and the lower arm 3 are displaced downward. Therefore, it is possible to prevent the lower arm 3 from moving into the vehicle body.

なお、上記実施形態では、破断誘起部２０が補強リブ３０ないし側壁１１ｂの先端に設けられた段部２０Ａによって形成される場合について説明したが、段部２０Ａに代えて、例えば図９（ａ），（ｂ）に示すように、破断誘起部２０の領域に位置する補強リブ３０ないし側壁１１ｂの肉厚ｔ１を、前方側の補強リブ３０の肉厚ｔ２に対して薄く形成してもよい。 In the above embodiment, the case where the fracture inducing portion 20 is formed by the stepped portion 20A provided at the tip of the reinforcing rib 30 or the side wall 11b has been described, but instead of the stepped portion 20A, for example, FIG. , (B), the thickness t1 of the reinforcing rib 30 or the side wall 11b located in the region of the fracture inducing portion 20 may be formed thinner than the thickness t2 of the reinforcing rib 30 on the front side.

また、この場合、破断誘起部２０の領域に位置する補強リブ３０ないし側壁１１ｂの肉厚ｔ１を、前方側の補強リブ３０の肉厚ｔ２に対して厚く形成してもよい。 In this case, the thickness t1 of the reinforcing rib 30 or the side wall 11b located in the region of the fracture inducing portion 20 may be formed thicker than the thickness t2 of the reinforcing rib 30 on the front side.

また、これに代えて、図１０に示すように、補強リブ３０ないし側壁１１ｂの先端部に設けた切欠き２０Ｂによって破断誘起部２０を形成してもよい。あるいは、図１１に示すように、サイドメンバ１１における車室側連結部１６の車体前方向側の部位を加熱し軟化させる熱処理を施こした熱処理部２０Ｃにより、前方からの衝撃力を受けた際に破断を促すように軟化させて破断誘起部２０を形成してもよい。 Alternatively, as shown in FIG. 10, the fracture inducing portion 20 may be formed by a notch 20B provided at the reinforcing rib 30 or the tip of the side wall 11b. Alternatively, as shown in FIG. 11, when an impact force from the front is received by the heat treatment portion 20 </ b> C that has been subjected to a heat treatment that heats and softens the vehicle body side connection portion 16 of the side member 11 on the front side of the vehicle body. The breakage inducing portion 20 may be formed by softening so as to promote breakage.

なお、この熱処理は破断誘起部２０を再結晶温度以上に加熱すればよく、例えば、アークトーチ、ないし電子ビーム，レーザービーム等にて４１０℃で２０秒程度の加熱を行うことでできる。 This heat treatment may be performed by heating the fracture inducing portion 20 to the recrystallization temperature or higher, for example, by heating at 410 ° C. for about 20 seconds with an arc torch, electron beam, laser beam or the like.

なお、図９，図１０，図１１において、その他の部分は、第１実施形態と同じであるので、同一部分には同一符号を付して説明は省略する。 9, 10, and 11, the other parts are the same as those in the first embodiment, so the same parts are denoted by the same reference numerals and description thereof is omitted.

なお、上記図９，図１０，図１１に示した破断誘起部２０（薄肉厚ｔ１，切欠き２０Ｂ，熱処理２０Ｃ）は単独に設けてもよく、あるいは、第１実施形態の段部２０Ａを含めて併用して設けるようにしてもよい。 Note that the fracture inducing portion 20 (thin wall thickness t1, notch 20B, heat treatment 20C) shown in FIGS. 9, 10, and 11 may be provided independently, or includes the step portion 20A of the first embodiment. May be provided together.

また、上記実施形態では、この発明に係るサスペンションメンバをフロントエンジン車に適用した場合について説明したが、この発明に係るサスペンションメンバをリアエンジン車に適用することも可能である。 In the above embodiment, the case where the suspension member according to the present invention is applied to a front engine vehicle has been described. However, the suspension member according to the present invention can also be applied to a rear engine vehicle.

この発明に係るアルミニウム合金製サスペンションメンバを示す平面図である。It is a top view which shows the suspension member made from an aluminum alloy which concerns on this invention. 上記サスペンションメンバの側面図である。It is a side view of the said suspension member. 上記サスペンションメンバの底面図である。It is a bottom view of the suspension member. この発明における車室側連結部と破断誘起部を示す底面斜視図である。It is a bottom perspective view showing a compartment side connection part and a fracture inducing part in this invention. この発明における破断誘起部の第１実施形態を示す拡大側面図である。It is an enlarged side view which shows 1st Embodiment of the fracture | rupture induction part in this invention. 図５のＩ−Ｉ線に沿う概略断面図（ａ）及び図５のII−II線に沿う概略断面図（ｂ）である。It is the schematic sectional drawing (a) in alignment with the II line of FIG. 5, and the schematic sectional drawing (b) in alignment with the II-II line of FIG. この発明におけるサスペンショウンメンバ本体と補助サイドメンバの連結部を示す断面図（ａ）及び（ａ）のIII−III線に沿う断面図（ｂ）である。It is sectional drawing (b) which follows the III-III line of sectional drawing (a) and (a) which shows the connection part of the suspension member main body and auxiliary | assistant side member in this invention. 衝撃によって破断される前の状態及び破断後の状態を示す概略側面図である。It is a schematic side view which shows the state before fracture | rupture by an impact, and the state after a fracture | rupture. この発明における破断誘起部の第２実施形態を示す要部底面斜視図（ａ）及び（ａ）のIV部の拡大底面図（ｂ）である。It is a principal part bottom perspective view (a) which shows 2nd Embodiment of the fracture | rupture induction part in this invention, and the expanded bottom view (b) of IV part of (a). この発明における破断誘起部の第３実施形態を示す拡大側面図である。It is an enlarged side view which shows 3rd Embodiment of the fracture | rupture induction part in this invention. この発明における破断誘起部の第４実施形態を示す概略底面図である。It is a schematic bottom view which shows 4th Embodiment of the fracture | rupture induction part in this invention.

１サスペンションメンバ
２サイドフレーム
３ロアアーム
４エンジン
１０サスペンションメンバ本体
１１サイドメンバ
１１ａ表面部
１１ｂ側壁
１１ｃ段差部
１２センタクロスメンバ
１３リアクロスメンバ
１４ファーストクロスメンバ
１５補助サイドメンバ
１６車室側連結部
１７中間連結部
１８先端連結部
２０破断誘起部
２０Ａ段部
２０Ｂ切欠き
２０Ｃ熱処理部 DESCRIPTION OF SYMBOLS 1 Suspension member 2 Side frame 3 Lower arm 4 Engine 10 Suspension member main body 11 Side member 11a Surface part 11b Side wall 11c Step part 12 Center cross member 13 Rear cross member 14 First cross member 15 Auxiliary side member 16 Vehicle compartment side connection part 17 Intermediate connection Part 18 Tip connection part 20 Breaking induction part 20A Step part 20B Notch 20C Heat treatment part

Claims

It consists of a pair of side members that extend in the front-rear direction of the vehicle body, and a cross member that connects both side members,
The side member is provided with a passenger compartment side connecting portion for forming a connecting portion to the vehicle body at the end portion on the passenger compartment side, and one or two or more in a portion opposite to the passenger compartment with respect to the passenger compartment side connecting portion. A suspension member provided with a suspension arm support part of
The side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the vehicle compartment side is at a low position, the vehicle compartment side connection portion is provided on the low position side, and the vehicle compartment side connection portion in the side member is provided. And a suspension inducing portion formed between the suspension arm support portion with the smallest distance between the vehicle compartment side connecting portion and
Said side members are made by projecting the reinforcing rib along the side member on the rear surface of the surface portion in the longitudinal direction comprising a region of at least the rupture inducing portion, the distal end portion of the reinforcing ribs, to form the fracture inducing portion A suspension member provided with a stepped portion.

It consists of a pair of side members that extend in the front-rear direction of the vehicle body, and a cross member that connects both side members,
The side member is provided with a passenger compartment side connecting portion for forming a connecting portion to the vehicle body at the end portion on the passenger compartment side, and one or two or more in a portion opposite to the passenger compartment with respect to the passenger compartment side connecting portion. A suspension member provided with a suspension arm support part of
The side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the vehicle compartment side is at a low position, the vehicle compartment side connection portion is provided on the low position side, and the vehicle compartment side connection portion in the side member is provided. And a suspension inducing portion formed between the suspension arm support portion with the smallest distance between the vehicle compartment side connecting portion and
It said side members are made by projecting the reinforcing rib along the side member on the rear surface of the surface portion in the longitudinal direction comprising a region of at least the rupture inducing portion, the thickness of the reinforcing ribs located in the region of the fracture inducing portion The suspension member is characterized by being changed before and after the fracture inducing portion.

It consists of a pair of side members that extend in the front-rear direction of the vehicle body, and a cross member that connects both side members,
The side member is provided with a passenger compartment side connecting portion for forming a connecting portion to the vehicle body at the end portion on the passenger compartment side, and one or two or more in a portion opposite to the passenger compartment with respect to the passenger compartment side connecting portion. A suspension member provided with a suspension arm support part of
The side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the vehicle compartment side is at a low position, the vehicle compartment side connection portion is provided on the low position side, and the vehicle compartment side connection portion in the side member is provided. And a suspension inducing portion formed between the suspension arm support portion with the smallest distance between the vehicle compartment side connecting portion and
Said side members are made by projecting the reinforcing rib along the side member on the rear surface of the surface portion in the longitudinal direction comprising a region of at least the rupture inducing portion, the distal end portion of the reinforcing ribs, to form the fracture inducing portion A suspension member provided with a notch.

It consists of a pair of side members that extend in the front-rear direction of the vehicle body, and a cross member that connects both side members,
The side member is provided with a passenger compartment side connecting portion for forming a connecting portion to the vehicle body at the end portion on the passenger compartment side, and one or two or more in a portion opposite to the passenger compartment with respect to the passenger compartment side connecting portion. A suspension member provided with a suspension arm support part of
The side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the vehicle compartment side is at a low position, the vehicle compartment side connection portion is provided on the low position side, and the vehicle compartment side connection portion in the side member is provided. And a suspension inducing portion formed between the suspension arm support portion with the smallest distance between the vehicle compartment side connecting portion and
Forming a strength reduction portion serving as the fracture inducing portion by a heat treatment between the distance is smallest suspension arm supporting portion of the inner casing side connecting portion of the cabin side connecting portion and the suspension arm support in the side members A suspension member characterized by that.

It consists of a pair of side members that extend in the front-rear direction of the vehicle body, and a cross member that connects both side members,
The side member is provided with a passenger compartment side connecting portion for forming a connecting portion to the vehicle body at the end portion on the passenger compartment side, and one or two or more in a portion opposite to the passenger compartment with respect to the passenger compartment side connecting portion. A suspension member provided with a suspension arm support part of
The side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the vehicle compartment side is at a low position, the vehicle compartment side connection portion is provided on the low position side, and the vehicle compartment side connection portion in the side member is provided. And a suspension inducing portion formed between the suspension arm support portion with the smallest distance between the vehicle compartment side connecting portion and
Said side members are made by projecting the reinforcing rib along the side member on the rear surface of the surface portion in the longitudinal direction comprising a region of at least the rupture inducing portion, the reinforcing ribs located in the region of the fracture inducing portion height The suspension member is characterized by being changed before and after the fracture inducing portion.

It consists of a pair of side members that extend in the front-rear direction of the vehicle body and a cross member that connects both side members,
The side member is provided with a vehicle compartment side connection portion that forms a connection portion to the vehicle body at an end portion on the vehicle compartment side, and one or two or more in a portion opposite to the vehicle compartment with respect to the vehicle compartment side connection portion. A suspension member provided with a suspension arm support part of
The side member is formed in a substantially crank shape in the front-rear direction of the vehicle body so that the vehicle compartment side is at a low position, the vehicle compartment side connection portion is provided on the low position side, and the vehicle compartment side connection portion in the side member is provided. And a suspension inducing portion formed between the suspension arm support portion having the smallest distance between the vehicle compartment side connecting portion and
Said side members are made by projecting the reinforcing rib along the side member on the rear surface of the surface portion in the longitudinal direction comprising a region of at least the rupture inducing portion, the height of the reinforcing ribs located in the region of the fracture inducing portion, and A suspension member, characterized in that the plate thickness is changed before and after the fracture inducing portion.

The suspension member according to any one of claims 1 to 6 ,
The suspension member is made of an aluminum alloy.