JP4587827B2 - Auto body structure - Google Patents

Description

  The present invention relates to a vehicle body structure of an automobile, and relates to a technique for improving safety at the time of a side collision.

In recent automobiles, a door beam such as a steel pipe welded structure product or a steel plate press-molded product is provided in the door in order to increase the safety at the time of a side collision (see, for example, Patent Document 1). The door provided with the door beam is significantly improved in strength and rigidity, so that it is difficult to be greatly deformed at the time of a side collision, and the collision energy is smoothly transmitted to the body. The body of an automobile provided with this type of door is more likely to have impact energy at the time of a side collision, so that it is desirable to increase the strength and rigidity against a side load. As a vehicle body structure that enhances the strength and rigidity of the body against lateral loads, for example, lean reinforcements manufactured by the hydroforming method, etc., are installed in the center pillar, roof, and floor, respectively. A structure in which a continuous closed cross-section structure is formed by joining by welding is known (see Patent Document 2).
JP 2002-225561 A (paragraph 0010, FIG. 1) Japanese Patent No. 35006266 (paragraph 0018, FIG. 12)

  In the vehicle body structure of Patent Literature 2, the strength and rigidity of the body at the center pillar portion are improved to some extent by the closed cross-section structure, but there are various problems relating to absorption of collision energy and the like. For example, in this vehicle body structure, since the strength and rigidity of the center pillar are higher than those of the front pillar and the rear pillar, stress concentrates on the connecting portion of each pillar at the time of a side collision. As a result, a so-called plastic hinge is generated at the connecting portion, the body is greatly deformed, and the rigidity is lost, so that the collision energy is not effectively absorbed. In addition, since the reinforcements forming the closed cross-section structure have different strengths and rigidity among the center pillar, the roof, and the floor, stress is concentrated on the joint portion at the time of a side collision. As a result, a plastic hinge is generated at the joint, and the closed cross-section structure is greatly deformed. Also, since the rigidity is lost, the collision energy cannot be effectively absorbed. It is possible to prevent the occurrence of plastic hinges by reinforcing the joints and joints, but in this case, other types of problems such as a sudden increase in the weight of the vehicle body and a decrease in fuel consumption and exercise performance occur. To do.

  The present invention has been made in view of such a background, and an object of the present invention is to provide a vehicle body structure for a vehicle in which large deformation of the body at the time of a side collision is suppressed.

The vehicle body structure according to the invention of claim 1 is a vehicle body structure in which a door beam (51) is installed on the front door (7), and the upper and lower parts of the left and right front pillars (11, 12) are connected to each other. A first annular skeleton portion (29) configured as above, a second annular skeleton portion (35) configured by connecting the upper and lower portions of the left and right center pillars (13, 14), and a steel pipe Ri Na bending molded to the said first loop members (28) to first form the first annular skeleton portion (29), Ri greens by molding bent steel pipe to cyclic, the second annular skeleton portion (35 And the left and right front pillars (11, 12) are closed cross-section structures formed by welding the inner panel (22) and the outer panel (23), wherein in the hollow portion (26) 1 holds the loop member (28), the right and left center pillars (13, 14) is an inner panel (31) and outer panel (32) and closed-section structure article obtained by welding and the hollow section (33 ) , The second loop member (34) is held, and the door beam (51) overlaps the outer panel (23) and the outer panel (32) in a side view of the vehicle.

According to the vehicle body structure of the automobile of the present invention , the collision energy applied to the door beam of the front door at the time of a side collision is effectively absorbed by being transmitted from the door beam to the first and second annular frame parts, and the plastic hinge Large deformation of the body caused by Moreover, it becomes easy to make the strength and rigidity of each part in the annular skeleton part uniform with respect to the side collision input, and the large deformation of the annular skeleton part due to the plastic hinge hardly occurs. In addition, an annular skeleton having a continuous closed cross section can be manufactured relatively easily and at low cost .

Hereinafter, an embodiment of a vehicle body structure to which the present invention is applied will be described in detail with reference to the drawings.
FIG. 1 is a perspective view showing a main part of a vehicle body structure of an automobile according to the embodiment. FIG. 2 is a perspective side view showing a main part of the vehicle body structure of the automobile according to the embodiment. FIG. 4 is a perspective view schematically showing transmission of a collision load at the time of a side collision, and FIG. 5 is a front view schematically showing a deformation state of the loop member at the time of a side collision. FIG.

<< Configuration of Embodiment >>
As shown in FIGS. 1 and 2, in the present embodiment, the present invention is applied to a vehicle body structure of a sedan type four-door passenger car. The body 1 of the present embodiment has a monocoque structure in which the front body 2, the roof panel 3, the floor panel 4, the left and right side members 5, 6 and the like are assembled by spot welding, 7 is formed with a front door opening 8 to which the front end is hinged and a rear door opening 10 to which a rear door (second door) 9 is hinged to the front end. The body 1 is provided with left and right front pillars 11 and 12 on the front end side of the front door opening 8, and left and right center pillars 13 and 14 are provided between the front door opening 8 and the rear door opening 10. It has been. A floor reinforcing frame 15 having a closed cross section with the floor panel 4 is joined to the upper surface of the rear portion of the floor panel 4.

<First cyclic skeleton>
A dash reinforcement 21 is integrated with the front body 2 at the lower rear end thereof. The dash reinforcement 21 is substantially U-shaped when viewed from the front, and its left and right ends are welded to the left and right front pillars 11 and 12. In the case of the present embodiment, the front pillars 11 and 12 are hollow structural products formed by welding and joining the inner panel 22 and the outer panel 23 as shown in a cross section of the main part in FIG. 3B, the dash reinforcement 21 is a hollow structure product formed by welding and joining the inner panel 24 and the outer panel 25. As shown in FIG. The front pillars 11 and 12 and the dash reinforcement 21 constitute a first annular skeleton portion 29 together with a first loop member (skeleton material) 28 held in the hollow portions 26 and 27. The first loop member 28 is formed by bending a steel pipe into an annular shape and welded to the lower center, and is welded to the front pillars 11 and 12 and the dash reinforcement 21.

<Second annular skeleton part>
The left and right center pillars 13 and 14 are hollow structure products formed by welding and joining the inner panel 31 and the outer panel 32 as shown in FIG. 3C, and are held in the hollow portion 33. A second annular skeleton 35 is formed together with the second loop member 34. The second loop member 34 is formed by bending a steel pipe into an annular shape and welded at the lower center, and is welded to the lower surfaces of the roof panel 3 and the floor panel 4 in addition to the center pillars 13 and 14.

<Third annular skeleton>
The floor reinforcing frame 15 has a rectangular shape formed by connecting the end portions of the front and rear cross members 41, 42 with left and right side rails 43, 44, as shown in FIG. A third annular skeleton 47 is formed together with the third loop member 46 housed in the hollow 45 between the floor panel 4. The third loop member 46 is formed by bending a steel pipe into an annular shape and then welded and joined at the lower center, and is welded and joined to the floor reinforcing frame 15.

<Door beam>
As shown in FIGS. 1 and 2, the front door 7 includes a front door beam 51 having a front portion branched in a Y shape. When the front door 7 is attached to the body 1, the front door beam 51 has the top and bottom front end portions 51 a and 51 b overlap the first annular skeleton portion 29 and the rear end portion 51 c is the second annular skeleton portion in a side view shown in FIG. 2. 35. The rear door 9 includes a rear door beam 52 whose rear portion is branched into a Y shape. When the rear door 9 is attached to the body 1, the rear door beam 52 has a front end portion 52a overlapping the second annular skeleton portion 35 and a lower rear end portion 52b overlapping the third annular skeleton portion 47 in a side view shown in FIG. .

<< Operation of Embodiment >>
When the vehicle is running or stopped, a vehicle or an obstacle may collide with the side surfaces of the front door and the rear door. In the present embodiment, as shown in FIG. 4, when a vehicle or an obstacle collides with the center of the front door 7, the collision load (indicated by an arrow) first acts on the front door beam 51 built in the front door 7. Then, the first door frame 51 is transmitted to the first annular frame 29 and the second ring frame 35 from the upper and lower front ends 51 a and 51 b and the rear end 51 c.

  When a collision load is transmitted from the side to the first annular skeleton portion 29 and the second annular skeleton portion 35, most of the collision load is deformed after the front pillar 11 and the center pillar 13 are deformed. It acts on the loop member 28 and the second loop member 34. Since the first loop member 28 and the second loop member 34 are formed in an annular shape as described above, the collision load applied from the side is dispersed over the entire circumference. As a result, as shown in FIG. 5, the first loop member 28 and the second loop member 34 are bent and deformed so as to expand up and down, and the collision load is effectively absorbed without causing large deformation of the body 1. .

≪Some modified examples≫
FIG. 6 is a perspective view of a main part showing a vehicle body structure of an automobile according to a partial modification.
As shown in the figure, the overall configuration of some modified examples is substantially the same as that of the above-described embodiment, but the structures of the first annular skeleton portion 29 and the third annular skeleton portion 47 are different. That is, in the case of a partial modification, the first annular skeleton portion 29 is not provided with a loop member, and the upper ends of the left and right front pillars 11 and 12 are connected by a relatively large-diameter cross pipe 61. An annular skeleton 29 is formed. Further, the third annular skeleton 47 does not include a loop member, and the floor reinforcing frame 15 itself is the third annular skeleton 47. Even in some modifications, the strength and rigidity of the body 1 at the time of a side collision can be sufficiently ensured by appropriately setting the plate thickness of each member.

  Although the description of the specific embodiment is finished as described above, the present invention is not limited to the above embodiment and can be widely modified. For example, in the above-described embodiment, the present invention is applied to a sedan type four-door passenger car. However, the present invention may be applied to a two-door car, a two-seat car, and the like. May be omitted. In addition, the specific structure of the loop member, including the specific structure of the body and the annular skeleton, can be appropriately changed without departing from the spirit of the present invention.

It is a principal part perspective view which shows the vehicle body structure of the motor vehicle which concerns on embodiment. It is a principal part see-through | perspective side view which shows the vehicle body structure of the motor vehicle which concerns on embodiment. It is principal part sectional drawing of a 1st-3rd cyclic | annular frame | skeleton part. It is a perspective view which shows typically transmission of the collision load at the time of a side collision. It is a front view which shows typically the deformation state of the loop member at the time of a side collision. It is a principal part perspective view which shows the vehicle body structure of the motor vehicle which concerns on a partial modification.

Explanation of symbols

1 Body 7 Front door 9 Rear door (second door)
11, 12 Front pillar 13, 14 Center pillar 15 Floor reinforcement frame 21 Dash reinforcement 28 First loop member (frame material)
29 1st cyclic | annular frame | skeleton part 34 2nd loop member (skeleton material)
35 Second annular frame 46 Third loop member (frame material)
47 Third annular frame 51 Front door beam 52 Rear door beam

Claims (1)

A vehicle body structure in which a door beam (51) is installed on a front door (7),
A first annular skeleton (29) configured by connecting the upper and lower portions of the left and right front pillars (11, 12);
A second annular skeleton (35) configured by connecting the upper and lower portions of the left and right center pillars (13, 14);
Steel Ri Na and bent molded annularly, the first of the first loop member (28) to form cyclic skeleton portion (29),
Ri Na and bent molded annular steel tubes, and a second loop member forming (34) said second annular skeleton portion (35),
The left and right front pillars (11, 12) are closed cross-section products formed by welding the inner panel (22) and the outer panel (23), and the first loop member (28) is formed in the hollow portion (26 ). Hold
The left and right center pillars (13, 14) are closed cross-section structures formed by welding the inner panel (31) and the outer panel (32), and the second loop member (34) is formed in the hollow portion (33 ). Hold
The vehicle body structure according to claim 1, wherein the door beam (51) overlaps the outer panel (23) and the outer panel (32) in a side view of the vehicle.

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