JP4810250B2 - Front body structure of automobile - Google Patents

Description

  The present invention relates to a front body structure of a vehicle in which a bumper beam is coupled to a front end of a pair of left and right front side frames and a front end of a front subframe disposed below the front side frame.

In order to enhance the shock absorption capability at the time of a frontal collision of the vehicle, as shown in FIG. 8, a bumper beam 02 (front end cross member) fixed to the front ends of a pair of left and right front side frames 01, 01 (side members) is provided. The linear first cross member 03 that connects the left and right front side frames 01 and 01, and the U-shaped second cross member 04 that is coupled to both ends of the first cross member 03 to form a rectangular frame. Is configured by the following Patent Document 1.
JP 2000-177651 A

  By the way, in the above conventional one, the second cross member 04 located below the first cross member 03 located on the upper side is located behind the vehicle body, so the second cross member 04 collides with the side sill of the other vehicle. Before the first cross member 03 collides with the door or center pillar of another vehicle, and the second cross member 04 does not have sufficient rigidity to receive the collision energy. There was a possibility of breaking into the doors and center pillars of the vehicle. Also, the left and right corners of the lower second cross member 04 are particularly low in rigidity and easily deform rearward. Therefore, in the event of an offset frontal collision with another vehicle, the bumper beam of the own vehicle and the bumper of the other vehicle The beams could slip back and forth without absorbing each other's collision energy, which could increase the damage of the collision.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to effectively absorb collision energy at the time of collision with another vehicle.

In order to achieve the above object, according to the first aspect of the present invention, the upper beam extends linearly in the vehicle width direction, and extends obliquely downward from both ends of the upper beam toward the vehicle width direction inward. The lower beam comprises a pair of lower beams whose lower ends are connected to each other, and has a bumper beam having a "D" shape or an inverted triangular shape in the front view, and a pair of front beams arranged in the longitudinal direction of the vehicle body. coupled to the fragile portion provided at the front end of the side frame, the lower end of the pair of Roabimu is connecting bracket extending longitudinally in the central portion of the front cross member of the front sub frame disposed below the front side frames A vehicle front body structure is proposed which is characterized by being coupled via

  According to the second aspect of the present invention, in addition to the configuration of the first aspect, the upper beam and the lower beam are substantially aligned in the longitudinal direction of the vehicle body, and the height of the lower end of the lower beam is the passenger car. A front body structure of an automobile is proposed, characterized in that it substantially matches the height of the side sill.

According to the invention described in claim 3, in addition to the configuration of claim 1 or claim 2, the rigidity of the fragile portion of the pair of front side frames is set to be higher than the rigidity of the front portion of the front subframe. Also proposed is a front body structure of an automobile characterized by being set low.

According to the configuration of the first aspect, the bumper beam linearly extends in the vehicle width direction, and a pair of the lower beams that extend obliquely downward toward the inner side in the vehicle width direction from both ends of the upper beam, and whose lower ends are connected to each other. by the Roabimu it is formed transversely of the "D" -shaped or inverted triangular shape in a front view, and is coupled to a weak portion provided at the front end of the front side frames at both ends of the pair of upper beams, a pair of Roabimu Since the lower end of the front is connected to the center of the front horizontal member of the front subframe via a connecting bracket extending in the front-rear direction , the bumper beam has a wide height from the front side frame to the front subframe when it collides with another vehicle. The collision energy is received in the range, and the collision energy is transferred to the front side frame and the front subframe. Can be effectively absorbed is transmitted to. Moreover, since the bumper beam as a whole has a “D” shape or an inverted triangular shape when viewed from the front , even if the collision energy is input to the lower beam, the lower beam exhibits sufficient rigidity, thereby reducing the collision energy. Transmission to the front side frame and the front subframe can be ensured. In addition, when the host vehicle collides with another vehicle and a load is input from the bumper beam to the front side frame, the weak part provided at the front end of the front side frame easily collapses, so that the upper beam It is possible to prevent penetration into the center pillar.

  According to the second aspect of the present invention, when the host vehicle collides with another vehicle on the side, the upper beam and the lower beam of the bumper beam of the host vehicle substantially coincide with each other in the longitudinal direction of the vehicle body. Although colliding at the same time, the lower beam collides with the high-rigidity side sill of the other vehicle and absorbs energy, thereby preventing the upper beam from penetrating into the low-rigidity door or center pillar of the other vehicle.

According to the third aspect of the present invention, when the host vehicle collides with another vehicle and a load is input from the bumper beam to the front side frame and the front subframe, the front side is lower in rigidity than the front portion of the front subframe. By easily crushing the weak part of the frame, it is possible to more reliably prevent the upper beam from penetrating into the door or center pillar of another vehicle.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 6 show a first embodiment of the present invention, in which FIG. 1 is a perspective view showing a skeleton of a front part of a vehicle body, FIG. 2 is a view in the direction of the arrow in FIG. 1, and FIG. FIG. 4 is a diagram illustrating an action at the time of a side collision with another vehicle (when the height of the other vehicle is low), FIG. 5 is an illustration of an action at the time of a side collision with another vehicle (another vehicle). FIG. 6 is an operation explanatory diagram at the time of a frontal collision with another vehicle.

  As shown in FIGS. 1 to 3, left and right front side frames 12, 12 extending in the longitudinal direction of the vehicle body are disposed along the left and right sides of an engine room 11 formed at the front of the vehicle body. A front subframe 13 that supports an engine and a suspension device (not shown) is disposed below the front side frames 12 and 12. The front sub-frame 13 includes a pair of left and right vertical members 14, 14 extending in the longitudinal direction of the vehicle body, a front lateral member 15 connecting the front ends of the pair of vertical members 14, 14 in the vehicle width direction, a pair of vertical members 14, 14 and a rear transverse member (not shown) for connecting the rear ends of the fourteen in the vehicle width direction.

  The bumper beam 16 includes an upper beam 17 that extends linearly in the vehicle width direction, a pair of left and right lower beams 18 and 18 that are curved in a downward arc as a whole, and a connecting bracket that is fixed to the lower rear surfaces of the lower beams 18 and 18. 19. Each of the lower beams 18 and 18 extends obliquely downward from the left and right ends of the upper beam 17 toward the inside in the vehicle width direction, and is continuous with each other at their lower ends. In the present embodiment, the pair of left and right lower beams 18 and 18 are configured as a single member. Accordingly, the bumper beam 16 has a “D” shape that is horizontally oriented when viewed from the front.

  The weak parts 12a, 12a made of different members are joined to the front parts of the left and right front side frames 12, 12 by bolts 20 ..., and the upper beam of the bumper beam 16 is connected to the front ends of these weak parts 12a, 12a. Both ends of 17 are connected with bolts 21. A connecting bracket 19 on the rear surface of the lower end of the bumper beam 16 is coupled to the central portion of the front lateral member 15 of the front subframe 13 with a bolt 22.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  When the host vehicle collides with another vehicle in a side surface, the upper beam 17 and the pair of lower beams 18 and 18 of the bumper beam 16 of the host vehicle have substantially the same position in the longitudinal direction of the vehicle body. At the same time, it collides with the side of another vehicle.

  As shown in FIG. 4, when the other vehicle is an ordinary passenger car and the height of the side sill 31 is relatively low, the lower ends of the lower beams 18, 18 of the bumper beam 16 of the own vehicle (position of the connecting bracket 19). Collides with the side sill 31 of another vehicle. Since the side sill 31 and the floor frame 32 connected to the side sill 31 have rigidity higher than that of the door 33 and the center pillar 34 and are not easily deformed, the collision energy input from the side sill 31 to the lower beams 18 and 18 of the bumper beam 16 of the host vehicle is It is transmitted from 19 to the rigid front sub-frame 13 and absorbed.

  Further, the upper beam 17 of the bumper beam 16 collides with the door 33 and the center pillar 34 of the other vehicle, but the lower beams 18 and 18 colliding with the side sill 31 effectively absorb the collision energy, so the upper beam 17 is the door of the other vehicle. 33 and the center pillar 34 can be minimized. Moreover, penetration of the upper beam 17 can be more effectively prevented by the fragile portions 12a, 12a provided at the front portions of the front side frames 12, 12 being crushed by the collision load.

  As shown in FIG. 5, when the other vehicle is a high vehicle such as an RV vehicle and the side sill 31 is at a relatively high position, the middle of the lower beams 18 and 18 of the bumper beam 16 of the own vehicle. The part collides with the side sill 31 of another vehicle. In this case, the ratio of the collision energy transmitted to the front side frames 12 and 12 is slightly increased as compared with the case described with reference to FIG. And transmitted to the front side frames 12 and 12, and the upper beam 17 can be minimized to penetrate the door 33 and the center pillar 34 of another vehicle.

  Next, consider the case where the host vehicle collides head-on with another vehicle in an offset state. As shown in FIG. 6A, when the lap ratio of the host vehicle and the other vehicle is relatively large, one of the lower beams 18 of the bumper beam 16 of the host vehicle and the end of the bumper beam 35 of the other vehicle By colliding with one of the tires 36, the impact of the collision can be absorbed, and the bumper beam 16 of the host vehicle and the bumper beam 35 of the other vehicle can be prevented from slipping through to increase the collision damage.

  Further, as shown in FIG. 6B, even if the lap ratio of the own vehicle and the other vehicle is relatively small and one of the lower beams 18 of the bumper beam 16 of the own vehicle does not collide with the bumper beam 35 of the other vehicle, When the lower beam 18 collides with the tire 36 of the other vehicle, it is possible to prevent the bumper beam 16 of the own vehicle and the bumper beam 35 of the other vehicle from slipping through and causing collision damage to increase.

  As described above, the bumper beam 16 formed by combining the upper beam 17 and the pair of lower beams 18 and 18 has a large vertical dimension. Therefore, even if the height of the side sill 31 and the height of the bumper beam 35 of other vehicles are variously different. The bumper beam 16 of the host vehicle can be reliably collided with the side sill 31 and the bumper beam 35 to absorb the collision energy.

  In addition, the bumper beam 16 has a laterally "D" shape as a whole, and the lower ends of the lower beams 18 and 18 are coupled to the front ends of the front subframe 13, so the rigidity of the lower beams 18 and 18 is shown in FIG. It is much higher than the rigidity of the second cross member 04 of the conventional bumper beam 02 shown, and the probability that the lower beams 18 and 18 are deformed and a slip-through occurs at the time of collision is greatly reduced.

  Further, the bumper beam 16 can be moved to the front side only by loosening the bolts 21... For connecting the upper beam 17 to the weakened portions 12 a and 12 a of the front side frames 12 and 12 and the bolts 22 for connecting the connecting bracket 19 to the front subframe 13. Since the frames 12 and 12 and the front subframe 13 can be separated, only the bumper beam 16 damaged by a light collision can be easily replaced.

  Also, since triangular spaces 23 and 23 (see FIG. 3) are formed below the left and right ends of the bumper beam 16, respectively, fog lights and night vision systems can be arranged using the spaces 23 and 23. it can.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  The lower beams 18 and 18 of the bumper beam 16 of the first embodiment are formed in an arc shape as a whole. However, the lower beams 18 and 18 of the second embodiment are linear, and thus the bumper beam 16. Has an isosceles triangle shape in front view.

  Also according to the second embodiment, it is possible to achieve the same operational effects as those of the first embodiment described above.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the embodiment, the pair of left and right lower beams 18 and 18 are configured as one member, but they may be configured as separate members and coupled at the lower end.

The perspective view which shows the frame | skeleton of the vehicle body front part of the vehicle which concerns on 1st Embodiment 2 direction view of FIG. 3 direction arrow view of FIG. Action explanatory diagram at the time of side collision with other vehicles (when the height of other vehicles is low) Action explanatory diagram at the time of side collision with other vehicle (when the height of other vehicle is high) Action explanatory diagram at the time of frontal collision with other vehicles The figure corresponding to the said FIG. 3 based on 2nd Embodiment. Illustration of conventional example

12 Front side frame
12a weak part 13 front subframe
15 Front transverse member 16 Bumper beam 17 Upper beam 18 Lower beam
19 Connecting bracket 31 Side sill

Claims (3)

An upper beam (17) that extends linearly in the vehicle width direction, and a pair of lower beams (18) that extend obliquely downward toward the inner side in the vehicle width direction from both ends of the upper beam (17) and whose lower ends are connected to each other. Comprising a bumper beam (16) having a "D" shape or an inverted triangular shape that is laterally viewed from the front ,
Both ends of the upper beam (17) are coupled to a fragile portion (12a) provided at the front end of a pair of front side frames (12) arranged in the longitudinal direction of the vehicle body, and the lower ends of the pair of lower beams (18) are The front sub-frame (13) disposed below the front side frame (12) is coupled to the center of the front lateral member (15) via a connecting bracket (19) extending in the front-rear direction. The front body structure of the car.   The positions of the upper beam (17) and the lower beam (18) in the longitudinal direction of the vehicle body substantially coincide with each other, and the height of the lower end of the lower beam (18) substantially coincides with the height of the side sill (31) of the passenger car. The front body structure of an automobile according to claim 1, wherein The rigidity of the weak part (12a) of the pair of front side frames (12) is set to be lower than the rigidity of the front part of the front subframe (13). The front body structure of the automobile described in 1.

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