JP2009255663A - Vehicle body rear part of automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce advancing amount of a rear collision vehicle into a rear part of one's own vehicle without complicating a structure and without causing a large increase of vehicle body weight. <P>SOLUTION: A rear cross member 36 is provided with a spare tire opposite part (suspending part 36A) facing to a spare tire 100 stored in a spare tire storing part 46 in the vehicle body longitudinal direction. During a rear collision, the spare tire 100 stored in the spare tire storing part 46 is punctured, and a metal wheel part 102 of the spare tire 100 is abutted on the rear cross member 36. The rear cross member 36 and a middle floor cross member 38 are connected by a sub rear frame 54 to make a transmission path of collision load. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle body rear structure of an automobile, and more particularly, to a countermeasure against a rear collision (rear collision) of a vehicle body rear structure.

  A vehicle body rear part structure of an automobile is generally disposed at the rear part of the vehicle body, extends in the longitudinal direction of the vehicle body, and has left and right rear frames. The left and right rear frames are fitted with rear floor panels, the vehicle longitudinal direction middle part is connected to each other by a rear cross member, the rear end part is connected to each other by a rear end cross member, a rear bumper frame member or a rear panel, and the front end part is a middle floor cross They are connected to each other by members. The left and right rear frames are connected to left and right side frame members on the front side of the vehicle body, which are called rocker members and side sills. Thus, deformation of the rear part of the vehicle body is suppressed.

  In such a vehicle body rear structure, a middle floor cross member that supports the rear wheels is assumed to have improved the effect of suppressing deformation of the vehicle rear part by distributing the transmission path of the collision load at the time of rear collision to the vehicle front part. Are connected by an auxiliary member called a brace (for example, Patent Document 1).

  In addition, in an automobile in which a spare tire is stored in a lying state in a spare tire storage section provided at the rear of the vehicle body, the spare tire is arranged in the spare tire storage section, the arrangement of the spare tire, the arrangement of fixtures, etc. When a collision load is applied, a spare tire rotates so as to get up to avoid interference with on-vehicle equipment (for example, Patent Document 2).

Further, as a vehicle in which a gas fuel tank is mounted on the rear portion of the rear seat, a vehicle in which a square frame-shaped support frame is attached between the left and right rear frames and a gas fuel tank is mounted on the support frame is known (for example, Patent Documents). 3).
JP 2006-232030 A JP 2007-276605 A JP 2005-206041 A

  The rear suspension member and the middle floor cross member connected by the auxiliary member are configured such that the transmission of the collision load at the time of rear collision to the front part of the vehicle body is directed from the rear frame to the side frame member on the front side of the vehicle body, and the rear suspension. This is performed in a distributed manner from the member to the path toward the middle floor cross member via the auxiliary member, but the impact load of the rear impact is received from the muffler (silencer) of the engine exhaust system arranged behind the rear suspension member. It has a structure to receive.

  However, in many cases, the muffler has a structure that is easily crushed. Therefore, the muffler is apt to be crushed from the rear end of the vehicle body to the rear suspension member, and there is a possibility that the front part of the vehicle body of the rear-end collision vehicle greatly enters the rear part of the own vehicle.

  It is preferable that the vehicle body structure has a small amount of rear-impact vehicles entering the rear of the host vehicle.In particular, in an automobile equipped with a gas fuel tank or battery at the rear of the rear seat, the amount of rear-end vehicles entering the rear of the host vehicle is reduced. I want to reduce it.

  The problem to be solved by the present invention is to reduce the amount of rear-impact vehicles entering the rear of the host vehicle without complicating the structure and without causing a large increase in the weight of the vehicle body.

  The rear body structure of an automobile according to the present invention includes a left and right rear frame disposed in the rear part of the vehicle and extending in the longitudinal direction of the vehicle, and an intermediate part in the longitudinal direction of the left and right rear frames extending in the vehicle body width direction. A rear cross member to be connected, a middle floor cross member that extends in the vehicle body width direction and connects the front end portions of the left and right rear frames to each other and is connected to the rear end of the front floor, and extends in the vehicle body front-rear direction. The rear cross member and the sub-rear frame for connecting the middle floor cross member to each other, and a spare tire storage portion for storing a spare tire in a state of being laid down on the vehicle rear side position from the rear cross member is installed, The rear cross member includes a spare tire stored in the spare tire storage section and a spare tire facing portion facing the vehicle body in the longitudinal direction. .

  In the vehicle body rear structure according to the present invention, preferably, an impact load absorbing member that is plastically deformed by a collision load is attached to the spare tire facing portion of the rear cross member.

  The vehicle body rear portion structure according to the present invention is particularly useful when applied to an automobile in which the upper portion of the rear cross member is an arrangement portion of an in-vehicle device.

  According to the rear structure of the vehicle body according to the present invention, the spare tire stored in the spare tire storage portion is punctured at the time of rear collision, and the metal wheel portion of the spare tire comes into contact with the rear cross member. It is transmitted to the front of the vehicle body through the spare tire, rear cross member, sub-rear frame, and middle floor cross member. Thus, the collision load at the time of rear collision is transmitted to the front of the vehicle body using the spare tire.

  As a result, the transmission of the collision load at the time of rear collision to the front of the vehicle is directed to the front of the vehicle through the path from the rear frame to the front of the vehicle and the spare tire through the rear cross member, the sub-rear frame, and the middle floor cross member. It is distributed to the route.

  Since the metal wheel part of the spare tire has a compressive strength that is less likely to be crushed than the muffler (silencer), the presence of the metal wheel part of the spare tire reduces the amount of rear-impact vehicles entering the rear of the host vehicle. be able to.

  An embodiment in which a vehicle body rear structure according to the present invention is applied to a fuel cell vehicle will be described below with reference to FIGS.

  In these drawings, reference numeral 10 denotes left and right rear wheels. The left and right rear wheels 10 are suspended from the vehicle body by known suspension mechanisms such as a rear suspension arm 12, a lateral rod 14, a stabilizer 16, a suspension spring 18, a damper 20, and the like.

  The rear part of the vehicle body is provided with left and right rear frames 30 that are arranged at the rear part of the vehicle body and extend parallel to each other in the longitudinal direction of the vehicle body as a skeleton member of the rear part of the vehicle body.

  The rear end portions of the left and right rear frames 30 are connected to each other by a rear panel 32 extending in the vehicle body width direction.

  First and second rear cross members 34 and 36 are provided at the vehicle body longitudinal direction intermediate portion of the left and right rear frames 30. The first and second rear cross members 34 and 36 each extend in the vehicle body width direction and connect the vehicle body longitudinal direction intermediate portions of the left and right rear frames 30 to each other. In other words, the first and second rear cross members 34 and 36 are joined to the left and right rear frames 30 by welding the left and right ends, respectively. The second rear cross member 36 is located on the front side of the vehicle body with respect to the first rear cross member 34.

  Middle floor cross members 38 are provided at the front end portions of the left and right rear frames 30. The middle floor cross member 38 extends in the vehicle body width direction and connects the front end portions of the left and right rear frames 30 to each other. In other words, the middle floor cross member 38 is joined to the left and right rear frames 30 by welding or the like at the left and right ends.

  The middle floor cross member 38 is connected to a front floor panel 40 and rear end portions of left and right side sills (rocker members) 42 extending in the longitudinal direction of the vehicle body.

  Rear floor panels 44 are attached on the left and right rear frames 30. An intermediate portion / rear end portion 30A from the vehicle body longitudinal direction intermediate portion to the rear end portion of the left and right rear frames 30 is at a position higher than the front end portion 30B, in other words, higher than the front floor panel 40. The first and second rear cross members 34 and 36 are provided in the intermediate portion / rear end portion 30A at the high position.

  A spare tire storage unit 46 for storing the spare tire 100 in a lying state is installed below the rear floor panel 44 behind the second rear cross member 36 in the vehicle body. The spare tire storage portion 46 is provided on the rear surface of the second rear cross member 36 so as to be opened and closed by a hinge 48 and has a spare tire holding frame 52 that is held in a closed position by a lock portion 50. The spare tire 100 is stored and held in a predetermined posture so that the spare tire 100 is sandwiched between the tire holding frame 52 and the inclined protrusion 44A formed on the lower bottom surface of the rear floor panel 44.

  In the present embodiment, the spare tire storage unit 46 stores the spare tire 100 in a leaning forward and downward inclined posture in which the front side of the vehicle body is lower than the rear side of the vehicle body at a position below the intermediate / rear end portion 30A of the rear frame 30. Hold.

  The spare tire 100 is a general spare tire having a metal wheel 102 and a rubber tire 104 mounted on the outer periphery of the metal wheel 102.

  Here, it is important that the second rear cross member 36 has a hanging portion 36A that hangs downward from the middle / rear end portion 30A of the rear frame 30 at the center in the vehicle width direction. However, this is that the spare tire 100 stored in the spare tire storage portion 46 forms a spare tire facing portion facing the vehicle body in the longitudinal direction.

  An impact load absorbing member 56 that is plastically deformed by a collision load is attached to a portion of the second rear cross member 36 facing the spare tire by the hanging portion 36A. The impact load absorbing member 56 has a groove-like cross-sectional shape, and has an upper end portion joined to the first rear cross member 34, and an upper end portion having an inclined rear surface 56A positioned rearward of the vehicle body from the lower end portion. The inclination angle of the inclined rear surface 56A is set to an angle suitable for capturing the spare tire 100 and controlling the attitude of the spare tire 100 when the impact load absorbing member 56 is plastically deformed (collapsed) by the rear impact. .

  A sub-rear frame 54 that extends in the longitudinal direction of the vehicle body and connects the second rear cross member 36 and the middle floor cross member 38 to each other is provided. That is, the second rear cross member 36 is rigidly connected to the middle floor cross member 38 on the vehicle body front side by the sub-rear frame 54. In the present embodiment, one sub-rear frame 54 is provided on each of the left and right sides of the hanging part 36A.

  On the sub-rear frame 54, a fuel cell unit housing 60 and a hydrogen tank 62 are mounted as in-vehicle devices. In addition, a tank base 64 is attached as an in-vehicle device arrangement portion at an upper position of the second rear cross member 36, and another hydrogen tank 66 is attached as an in-vehicle device on the tank base 64. Yes. In-vehicle devices arranged in the portion include a fuel tank in an internal combustion locomotive (engine vehicle) and a power supply unit in a hybrid vehicle.

  As shown in FIG. 5, when the vehicle (rear collision vehicle) 200 collides with the rear part of the vehicle body, the spare tire 100 stored in the spare tire storage unit 46 is punctured, and the metal wheel 104 portion of the spare tire 100 is obtained. Comes into contact with the hanging portion (spare tire facing portion) 36A of the second rear cross member 36 and pushes the hanging portion 36A forward of the vehicle body.

  Thereby, the collision load at the time of rear collision is transmitted to the middle floor cross member 38 through the spare tire 100, the second rear cross member 36, and the sub-rear frame 54, and further to the front of the vehicle body by the front floor panel 40. . In this manner, the collision load at the time of rear collision is transmitted to the front of the vehicle body using the spare tire 100.

  As a result, the transmission of the collision load at the time of rear collision to the front of the vehicle body is forwarded from the rear frame 30 to the front of the vehicle body by the side sill 42 and the like, the second rear cross member 36, the sub-rear frame 54, This is performed in a distributed manner along the route toward the front of the vehicle body via the middle floor cross member 38. Thereby, the deformation of the constituent members at the rear of the vehicle body is reduced.

  Since the metal wheel 102 portion of the spare tire 100 has a compressive strength that is less likely to be crushed than the muffler (silencer), the presence of the metal wheel 102 portion of the spare tire 100 causes the rear-impact vehicle 200 to the rear of the host vehicle. The amount of entry can be sufficiently reduced.

  The impact load absorbing member 56 is plastically deformed (collapsed) by the rear impact, captures the spare tire 100 by setting an appropriate inclination angle of the inclined rear surface 56A, and changes the attitude of the spare tire 100 to the second rear cross member 36. It is set to an angle suitable for load transmission. Thereby, the transmission of the impact load to the second rear cross member 36 by the spare tire 100 at the time of the rear collision is performed well.

  Further, the impact load absorbing member 56 absorbs the impact load by being plastically deformed (collapsed) by the rear impact.

  For this reason, the spare tire 100 stored in the spare tire storage unit 46 is effectively used, without complicating the structure and without causing a large increase in the weight of the vehicle body. The approaching amount of the collision vehicle can be sufficiently reduced.

It is sectional drawing of the vehicle body rear part which shows one Embodiment which applied the vehicle body rear part structure by this invention to the fuel cell vehicle. 1 is a bottom view of a rear part of a vehicle body showing one embodiment in which a vehicle body rear part structure according to the present invention is applied to a fuel cell vehicle. It is a rear view of the principal part of the vehicle body rear part which shows one embodiment which applied the vehicle body rear part structure by this invention to the fuel cell vehicle. 1 is a perspective view of a rear part of a vehicle body showing one embodiment in which a rear body structure according to the present invention is applied to a fuel cell vehicle. It is sectional drawing which shows the example of a rear-end collision state of the vehicle body rear part structure of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rear wheel 18 Suspension spring 30 Rear frame 32 Rear panel 34 1st rear cross member 36 2nd rear cross member 36A Hanging part (spare tire opposing part)
38 Middle floor cross member 40 Front floor panel 42 Side sill 44 Rear floor panel 46 Spare tire storage part 54 Sub rear frame 56 Impact load absorbing member 60 Fuel cell unit housing 62, 66 Hydrogen tank 100 Spare tire

Claims (3)

Left and right rear frames arranged at the rear of the vehicle body and extending in the vehicle longitudinal direction;
A rear cross member extending in the vehicle body width direction and connecting the vehicle body longitudinal direction intermediate portions of the left and right rear frames to each other;
A middle floor cross member that extends in the vehicle body width direction and connects the front end portions of the left and right rear frames to each other and is connected to the rear end of the front floor;
A sub-rear frame extending in the longitudinal direction of the vehicle body and connecting the rear cross member and the middle floor cross member to each other;
A spare tire storage section is installed in the vehicle rear position from the rear cross member to store the spare tire in a laid-down state,
The rear cross member is a rear body structure of an automobile including a spare tire stored in the spare tire storage portion and a spare tire facing portion facing the front and rear direction of the vehicle body.   The vehicle body rear structure according to claim 1, wherein an impact load absorbing member that is plastically deformed by a collision load is attached to a portion of the rear cross member that faces the spare tire.   The rear body structure of an automobile according to claim 1 or 2, wherein an upper part of the rear cross member is an arrangement part of an in-vehicle device.

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