Vehicle shock absorbing structure

Abstract

To provide an impact absorbing structure of a vehicle capable of securing a necessary resistance force irrespective of an input direction from a collision body.SOLUTION: An impact absorbing structure includes: an impact absorbing part 31 installed in a front end side of a vehicle, extending in a vehicle width direction, and having a front end forming a collision part with a collision body; and a bracket part 32 having a front end connected to a rear end of the impact absorbing part 31 and interposed between the impact absorbing part 31 and a vehicle body 4. In the impact absorbing structure, the deformation control part 3b is provided in a connection portion between the impact absorbing part 31 and the bracket 32, the deformation control part 3b extending obliquely upward to the front and formed to be more brittle than a front side of the connection portion in the impact absorbing part 31 and a rear side of the connection portion in the bracket part.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to an impact absorbing structure for a vehicle that includes an impact absorbing portion extending in the vehicle width direction. [Background technology]

[0002] One proposed vehicle impact absorption structure includes an L-shaped bracket in a front view that connects the upper front end of a resin front end panel extending in the vehicle width direction to the radiator upper support of the vehicle body (see, for example, Patent Document 1). In the impact absorption structure described in Patent Document 1, in the event of a frontal collision with a collision body, the bracket supports the upper part of the collision body, thereby reducing the degree of bending of the upper part relative to the lower part of the collision body, and further, if a pedestrian's buttocks fall onto the front end of the hood, the bracket easily bends downward, reducing the reaction force on the thighs. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-264495 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the impact absorption structure described in Patent Document 1, the bracket is the main energy absorption part, and when the input from the colliding body acts at a downward angle toward the rear, the bracket bends easily, but there is a risk that the resistance against the colliding body will be insufficient.

[0005] The present invention has been made in consideration of the above circumstances, and its object is to provide an impact absorbing structure for a vehicle that can ensure the necessary resistance regardless of the input direction from the colliding body. [Means for solving the problem]

[0006] According to the present invention, there is provided an impact absorbing structure for a vehicle, comprising: an impact absorbing section that is installed at the front end side of the vehicle, extends in the vehicle width direction, and whose front end forms a collision point with a collision body; and a bracket section that has its front end connected to the rear end of the impact absorbing section and is interposed between the impact absorbing section and the vehicle body, and at the connection portion between the impact absorbing section and the bracket section, a deformation control section is provided that extends diagonally upward toward the front and is formed to be weaker than the front side of the connection portion in the impact absorbing section and the rear side of the connection portion in the bracket section.

[0007] According to this vehicle impact absorption structure, a colliding body approaching from the rear comes into contact with the front end of the impact absorbing section, and energy is absorbed by the deformation of the impact absorbing section. When the impact from the colliding body acts horizontally rearward, a bending force acts on the deformation control section, causing the front end of the deformation control section to move diagonally upward and rearward, starting from the rear end of the deformation control section, and the deformation control section is bent. On the other hand, when the impact from the colliding body acts obliquely downward toward the rear, a compressive force acts on the deformation control section, and the deformation control section generates a greater resistance than when the impact from the colliding body acts horizontally rearward. In this way, the deformation mode of the deformation control unit can be changed depending on the input direction from the impact body, and a resistance force according to the input direction can be generated. At this time, energy can be absorbed by the deformation of the shock absorbing unit regardless of the input direction from the impact body, and the necessary resistance force can be secured for each input direction.

[0008] In the above-described vehicle impact absorbing structure, the bracket portion may have a predetermined dimension in the vertical direction, with an upper end connected to the vehicle body and a lower end disposed at a distance from the vehicle body.

[0009] According to this vehicle impact absorption structure, the lower end of the bracket portion is not connected to the vehicle body, and therefore, in the early stages of a collision when the input from the impacting body acts at a downward angle toward the rear, the lower end of the bracket portion is allowed to move rearward, suppressing a sudden increase in the acceleration of the impacting body due to excessive resistance generated in the impact absorbing portion and bracket portion.

[0010] In the above-described vehicle impact absorbing structure, the vehicle body may have a pair of left and right radiator panels extending in the vertical direction, and the lower end side of the bracket portion may be disposed in front of the radiator panels.

[0011] With this vehicle impact absorbing structure, when an impact from a colliding object acts obliquely downward toward the rear, the lower end of the bracket moves rearward in the early stages of the collision and eventually comes into contact with the radiator panel. After this, the lower end of the bracket is supported by the radiator panel, and a relatively large resistance is generated by the impact absorbing portion and the bracket.

[0012] In addition, in the above-mentioned vehicle impact absorption structure, the vehicle body may have a pair of left and right radiator panels extending in the vertical direction, and a radiator upper support connecting the upper ends of each radiator panel and extending in the vehicle width direction, and the upper end side of the bracket portion may be connected to the radiator upper support.

[0013] According to this vehicle impact absorption structure, the impact absorbing section is positioned in front of the radiator upper support, and when the input from the thigh to the impact absorbing section acts at a downward angle toward the rear during a collision with a pedestrian, it is possible to generate the necessary resistance while suppressing a sudden increase in acceleration of the thigh. [Effects of the Invention]

[0014] According to the vehicle impact absorbing structure of the present invention, it is possible to ensure the necessary resistance regardless of the input direction from the impact body. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is an external perspective view of a vehicle showing an embodiment of the present invention; [Figure 2] FIG. [Figure 3] FIG. 2 is an exploded perspective view illustrating the shock absorbing structure. [Figure 4] FIG. [Figure 5]FIG. [Figure 6] FIG. 4 is a side cross-sectional explanatory view of an upper impact absorber. [Figure 7] 10A and 10B are explanatory views of the operation of the upper impact absorber, showing the behavior when a horizontal impact is applied from a collision part of the impact absorbing part. [Figure 8] 10A and 10B are explanatory views of the operation of the upper impact absorber, showing the behavior when an impact is applied obliquely downward rearward from the collision point of the impact absorbing portion. DETAILED DESCRIPTION OF THE INVENTION

[0016] 1 to 8 show one embodiment of the present invention, in which FIG. 1 is an external perspective view of a vehicle showing one embodiment of the present invention, FIG. 2 is an explanatory perspective view of the front part of the vehicle body, FIG. 3 is an explanatory exploded perspective view of the front part of the vehicle body, FIG. 4 is an explanatory perspective view of the upper impact absorber, FIG. 5 is an explanatory exploded perspective view of the upper impact absorber, FIG. 6 is an explanatory side cross-sectional view of the upper impact absorber, FIG. 7 is an explanatory diagram of the operation of the upper impact absorber showing its behavior when a horizontal impact is applied from the collision part of the impact absorbing part, and FIG. 8 is an explanatory diagram of the operation of the upper impact absorber showing its behavior when a diagonally downward impact is applied rearward from the collision part of the impact absorbing part.

[0017] As shown in FIG. 1, the impact absorbing structure of this vehicle 100 is provided behind a bumper face 101, which forms the design surface at the front end of the vehicle 100. As shown in FIG. 2, a plurality of impact absorbers 1, 2, and 3 extending in the vehicle width direction are provided behind the bumper face 100. For the sake of explanation, FIG. 2 shows the bumper face 100 removed from the vehicle body 4. In this embodiment, three impact absorbers are provided: a lower impact absorber 1, a central impact absorber 2, and an upper impact absorber 3. Each of the impact absorbers 1, 2, and 3 is fixed to a predetermined location on the vehicle body 4.

[0018] 2, the vehicle body 4 is formed by assembling panel-shaped members formed, for example, by press-molding steel plates and joining them by spot welding, etc. The vehicle body 4 includes a pair of left and right side frames (not shown) extending in the front-rear direction, a bumper beam 41 connecting the front ends of the side frames via brackets and extending in the vehicle width direction, a pair of left and right radiator panels 42 connected to the front ends of the side frames and extending in the up-down direction, a radiator lower support 43 connecting the lower ends of the radiator panels 42 and extending in the vehicle width direction, a radiator upper support 44 connecting the upper ends of the radiator panels 42 and extending in the vehicle width direction, and a pair of left and right connecting members 45 connecting the vehicle width direction ends of the radiator upper support 44 to a pair of left and right upper frames (not shown) extending in the front-rear direction. The bumper beam 41 is formed to be longer outward in the vehicle width direction than the radiator upper support 44, and a pair of left and right headlamps (not shown) are arranged outward in the vehicle width direction from the radiator upper support 44.

[0019] The vehicle body 4 also includes a subframe 46. The subframe 46 has a pair of left and right front-rear extending portions 46a extending in the front-rear direction below each side frame, and a vehicle width extending portion 46b connecting the front ends of the front-rear extending portions 46a and extending in the vehicle width direction. The vehicle width extending portion 46b is positioned forward of the radiator lower support 43.

[0020] The lower impact absorber 1 is provided in front of the vehicle width extending portion 46b of the subframe 46. In the present embodiment, the lower impact absorber 1 is configured by dividing it into a front portion 11 and a rear portion 12, and the front portion 11 and the rear portion 12 are integrally provided to the vehicle body 4. The material of the lower impact absorber 1 is arbitrary, but can be resin, for example, and in the present embodiment, the front portion 11 and the rear portion 12 are made of non-foamed polypropylene.

[0021] The central impact absorber 2 is provided in front of the bumper beam 41. In this embodiment, the central impact absorber 2 is divided into a front portion 21 and a rear portion 22, which are integrally provided on the vehicle body 4. The central impact absorber 2 may be made of any material, such as metal or resin, and in this embodiment, the front portion 21 is made of non-foamed polypropylene, and the rear portion 22 is made of foamed polypropylene.

[0022] The upper impact absorber 3 is provided in front of the radiator upper support 44. As shown in FIG. 4, the upper impact absorber 3 has an impact absorbing portion 31 whose front end forms the part that collides with a colliding object, and a bracket portion 32 that is interposed between the impact absorbing portion 31 and the vehicle body 4. The upper impact absorber 3 may be made of any material, for example, metal, and in this embodiment, the impact absorbing portion 31 and the bracket portion 32 are made of steel plate. As shown in FIG. 4, the bracket portion 32 is made up of multiple types of bracket members 33, 34, and 35, and in this embodiment, it is made up of three types of bracket members 33, 34, and 35, as shown in FIG. 5.

[0023] The first bracket member 33 extends in the vehicle width direction as a whole along the radiator upper support 44, and as shown in FIG. 6, has an upper wall 33a extending in the front-rear direction in a side view, a rear wall 33b extending downward from the rear end of the upper wall 33a and sloping rearward, and a front wall 33c extending downward from the front end of the upper wall 33a. As shown in FIG. 5, the first bracket member 33 has a vehicle body connection portion 33d at a predetermined location in the vehicle width direction, extending rearward from the lower end of the rear wall 33b and connecting to the upper surface of the radiator upper support 44. In this embodiment, the vehicle body connection portion 33d is provided at four locations: two in the center of the vehicle width direction and two on the outer sides of the vehicle width direction. The vehicle body connection portions 33d on the outer sides of the vehicle width direction are provided at the connection portions of the radiator upper support 44 with each radiator panel 42. The first bracket member 33 also has a front connection portion 33e at a predetermined location in the vehicle width direction, which extends forward from the lower end of the front wall 33c and is connected to the impact absorbing portion 31. In this embodiment, the front connection portion 33e is provided at three locations: one at the center in the vehicle width direction and two on the outer sides in the vehicle width direction.

[0024] As shown in Fig. 5, a pair of second bracket members 34 are provided on the left and right sides corresponding to the vehicle body connection portions 33d of the first bracket member 33 on the outer sides in the vehicle width direction. In a side view, the second bracket member 34 has an upper wall 34a extending in the front-to-rear direction and a front wall 34b extending downward from the front end of the upper wall 34a. As shown in Fig. 6, the rear end of the upper wall 34a is sandwiched between the vehicle body connection portion 33d of the first bracket member 33 and the radiator upper support 44, and the front end protrudes forward from the radiator upper support 44. The rear end of the upper wall 34a, together with the vehicle body connection portion 33d of the first bracket member 33, is fixed to the radiator upper support 44 by bolts or the like. Note that the vehicle body connection portion 33 on the vehicle width direction center side of the first bracket member 33 is fixed to the radiator upper support 44 by bolts or the like without being engaged with the second bracket member 34. The front wall 34b extends in the vertical direction at a distance from the radiator panel 42 in the front-to-rear direction, and its lower end forms a free end that is not connected to the vehicle body 4. The lower end side of the front wall 34b is connected to the third bracket member 34. As shown in Figure 5, in this embodiment, lower connection portions 34c that extend downward to connect to the third bracket member 35 are formed on both ends of the lower end of the front wall 34b in the vehicle width direction.

[0025] A pair of third bracket members 35 are provided on the left and right sides corresponding to the second bracket members 34. As shown in FIG. 6, the third bracket member 35 has a main wall 35a that extends obliquely upward toward the front in a side view, with the rear end of the main wall 35a connected to the second bracket member 34 and the front end of the main wall 35a connected to the impact absorbing unit 31. As shown in FIG. 5, in this embodiment, lower connection portions 35b that extend downward to connect to the second bracket member 34 are formed at both ends of the rear end of the main wall 35a in the vehicle width direction. The lower connection portions 34c, 35b of the bracket members 34, 35 are joined by welding or the like while overlapping each other. In addition, a front connection portion 35c that extends obliquely upward toward the front to connect to the impact absorbing unit 31 is formed at the front end of the main wall 35a, toward the center in the vehicle width direction. In this embodiment, the front connection portion 35c is provided on the main wall 35a via an inclined portion 35d that extends downward toward the front. Furthermore, as shown in Fig. 5, the third bracket member 35 has a pair of left and right side walls 35e that extend upward from both ends of the main wall 35a in the vehicle width direction, and flange portions 35f that extend outward to the left and right from the upper ends of each side wall 35e. Each flange portion 35f is joined to the lower surface of the upper wall 33a of the first bracket member 33 by welding or the like.

[0026] The impact absorbing portion 31 as a whole extends in the vehicle width direction in front of the first bracket member 33 and is curved so that the center side in the vehicle width direction protrudes further forward than both end sides in the vehicle width direction. As shown in Fig. 6, the impact absorbing portion 31 has, in a side view, a main wall 31a that slopes downward toward the front, a front wall 31b that extends downward from the front end of the main wall 31a, an inclined wall 31c that slopes downward toward the rear from the lower end of the front wall 31b, and a lower wall 31d that extends downward from the rear end of the inclined wall 31c.

[0027] The impact absorbing portion 31 has an upper connection portion 31e at a predetermined location in the vehicle width direction, which extends rearward from the rear end of the main wall 31a and is connected to the first bracket member 33. In this embodiment, the upper connection portions 31e are provided in three locations: one in the center in the vehicle width direction and two on the outer sides in the vehicle width direction, corresponding to the front connection portions 33e of the first bracket member 33. The front connection portion 33e of the first bracket member 33 and the upper connection portion 31e of the impact absorbing portion 31 are joined by welding or the like, or fixed with bolts or the like. In this embodiment, the upper connection portion 31e of the impact absorbing portion 31 and the front connection portion 33e of the first bracket member 33 form an upper deformation control portion 3a extending in the front-to-rear direction. The upper deformation control section 3a is formed to be weaker than the main wall 31a of the impact absorbing section 31 located in front of the upper deformation control section 3a and the front wall 33c of the first bracket member 33 located in rear of the upper deformation control section 3a.

[0028] The impact absorbing portion 31 also has lower connection portions 31f at predetermined locations in the vehicle width direction, which extend from the lower end of the lower wall 31d at an inclined downward rearward and are connected to the third bracket member 35. In this embodiment, the lower connection portions 31f are provided in two locations on the outer side in the vehicle width direction, corresponding to the front connection portions 35c of the third bracket member 35. The front connection portions 35c of the third bracket member 35 and the lower connection portion 31e of the impact absorbing portion 31 are joined by welding or the like while overlapping each other. In this embodiment, the lower connection portions 31f of the impact absorbing portion 31, the front connection portions 35c of the third bracket member 35, and the inclined portions 35d form a lower deformation control portion 3b that extends at an inclined downward rearward. The lower deformation control section 3b is formed to be weaker than the lower wall 31d of the impact absorbing section 31 located in front of the lower deformation control section 3b and the main wall 35a of the third bracket member 35 located in rear of the lower deformation control section 3b.

[0029] With the impact absorbing structure configured as described above, a colliding body that enters rearward at a relatively high position comes into contact with the front end of the impact absorbing section 31 of the upper impact absorber 3, and energy is absorbed by the deformation of the impact absorbing section 31. Here, we will explain the behavior of the upper impact absorber 3 when the impact from the colliding body acts horizontally rearward and when it acts obliquely downward toward the rear.

[0030] As shown in FIG. 7 , when a horizontal rearward impact is applied from a colliding object, a bending force acts on the lower deformation control section 3b. Starting from the rear end of the lower deformation control section 3b, the front end of the lower deformation control section 3b moves upward and diagonally rearward, causing the lower deformation control section 3b to bend. In this embodiment, the rear end of the front connecting section 35c of the third bracket member 35, which extends downward toward the rear, is continuous with the front end of the inclined section 35d, which extends downward toward the front. Therefore, the third bracket member 35 is easily bent at the intersection of the front connecting section 35c and the inclined section 35d. At this time, the lower end of the second bracket member 34, located behind the lower deformation control section 3b, is hardly deformed. Meanwhile, a compressive force acts on the upper deformation control section 3a, generating a relatively large resistance. As a result, the impact absorbing section 31 and the first bracket member 33 are primarily crushed in the front-to-rear direction. For example, when the vehicle collides head-on with an obstacle and a horizontal input acts on the impact absorbing section 31 from the obstacle, the required resistance can be generated.

[0031] 8 , when an input from a colliding object acts obliquely downward toward the rear, a compressive force acts on the lower deformation control portion 3b, and the lower deformation control portion 3b generates a relatively large resistance. In this embodiment, the lower end of the second bracket member 34 forming the lower end of the bracket portion 32 is not connected to the vehicle body 4, and therefore, in the early stage of the collision, the lower end of the second bracket member 34 is allowed to move rearward, suppressing a sudden increase in the acceleration of the colliding object due to excessive resistance generated by the impact absorbing portion 31 and the bracket portion 32. After the lower end of the second bracket member 34 moves rearward and abuts against the radiator panel 42, the lower end of the bracket portion 32 is supported by the radiator panel 42, and therefore, a relatively large resistance is generated by the impact absorbing portion 31 and the bracket portion 32. Meanwhile, a bending force acts on the upper deformation control section 3a, causing the front end of the upper deformation control section 3a to move diagonally downward and rearward starting from the rear end of the upper deformation control section 3a, thereby bending the upper deformation control section 3a. As a result, mainly the impact absorbing section 31, the second bracket member 33, and the third bracket member 34 are crushed in the front-to-rear direction. In this embodiment, the impact absorbing section 31 of the upper impact absorber 3 is located in front of the radiator upper support 44, and when an input from the thigh acts on the impact absorbing section 31 diagonally downward and rearward during a collision with a pedestrian, it is possible to generate the necessary resistance while suppressing a sudden increase in thigh acceleration.

[0032] As described above, the shock absorbing structure of this embodiment changes the deformation mode of each deformation control section 3a, 3b depending on the input direction from the colliding body, and generates a resistance according to the input direction. At this time, energy can be absorbed mainly by the deformation of the shock absorbing section 31, regardless of the input direction from the colliding body, and the necessary resistance can be secured for each input direction.

[0033] In the above embodiment, the impact absorbing structure includes three impact absorbers, but the number of impact absorbers can be changed as desired. Also, although the present invention has been applied to an upper impact absorber installed on the radiator upper support, it is also possible to apply the present invention to a center impact absorber installed on the bumper beam or a lower impact absorber installed on the radiator lower support.

[0034] In the above embodiment, the deformation control section is provided at two locations, one on the upper side and one on the lower side, but if the deformation control section extends diagonally upward toward the front, sufficient resistance can be generated when an input diagonally downward toward the rear acts on the front end of the impact absorbing section. Also, although the deformation control section is configured from a connection section between the impact absorbing section and the bracket section, for example, a connection member that connects the impact absorbing section and the bracket section can be separately provided to serve as the deformation control section, and the specific configuration of the deformation control section can be changed as desired.

[0035] In the above embodiment, the lower end of the bracket is disposed at a distance from the vehicle body, but the lower end of the bracket may be connected to the vehicle body. In this case, when a collision object exerts a downward, rearward force on the impact absorbing section, a relatively large resistance force can be generated from the initial stage of the collision.

[0036] Although the embodiments of the present invention have been described above, the invention according to the claims is not limited to the embodiments described above. It should be noted that not all of the combinations of features described in the embodiments are necessarily essential to the means for solving the problems of the invention. [Explanation of symbols]

[0037] 3 Upper shock absorber 3b Transformation control section 4. Body 31 Shock absorbing part 32 Bracket part 42 Radiator panel 44 Radiator upper support 100 vehicles

Claims

1. an impact absorbing portion that is installed on the front end side of the vehicle, extends in the vehicle width direction, and has a front end that forms a collision portion with a collision body; a bracket portion having a front end connected to a rear end of the shock absorbing portion and disposed between the shock absorbing portion and a vehicle body, a deformation control portion is provided at a connection portion between the shock absorbing portion and the bracket portion, the deformation control portion extending obliquely upward toward the front and formed to be weaker than a front side of the connection portion of the shock absorbing portion and a rear side of the connection portion of the bracket portion; The bracket portion has a predetermined dimension in the vertical direction, an upper end side is connected to the vehicle body, and a lower end side is positioned at a distance from the vehicle body, in this vehicle shock absorbing structure.

2. The vehicle body has a pair of left and right radiator panels extending in a vertical direction, The shock absorbing structure for a vehicle according to claim 1 , wherein the lower end side of the bracket portion is disposed in front of the radiator panel.

3. The vehicle body includes a pair of left and right radiator panels extending in a vertical direction, and a radiator upper support connecting upper ends of the radiator panels and extending in a vehicle width direction, 3. The shock absorbing structure for a vehicle according to claim 2, wherein an upper end side of the bracket portion is connected to the radiator upper support.

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