Vehicle front structure
The vehicle front structure with a lower grille and absorber design, featuring minimized gaps and vertical columns, addresses the deformation challenge, enhancing impact absorption and reducing pedestrian injuries by ensuring early rebound and adequate reaction force.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- TOYOTA MOTOR EAST JAPAN
- Filing Date
- 2024-12-20
- Publication Date
- 2026-07-02
Smart Images
Figure 2026110115000001_ABST
Abstract
Description
Technical Field
[0001] This specification discloses the structure of the front part of a vehicle.
Background Art
[0002] Generally, when a vehicle collides with a pedestrian, it is required to appropriately protect the pedestrian's legs. Therefore, conventionally, a test has been conducted in which an impactor simulating the pedestrian's legs is made to collide with the vehicle to check the injury value of the pedestrian at the time of collision. Generally, in a vehicle, after the impactor collides with the front surface of the vehicle, it is required that the lower part of the impactor bounce back to the front of the vehicle at an early stage and the upper part of the impactor fall onto the hood of the vehicle.
[0003] Normally, a lower absorber is provided at the lower part of the front of the vehicle, and the lower part of the impactor is bounced back to the front of the vehicle by the reaction force received from this lower absorber. However, at the time of collision, if the lower absorber is greatly deformed toward the rear side of the vehicle, the lower part of the impactor cannot be sufficiently bounced back.
[0004] Therefore, some techniques for suppressing the deformation of the lower absorber have been proposed. For example, Patent Document 1 discloses a technique in which an engagement rib protruding toward the rear of the vehicle is provided on a bumper cover disposed on the front side of the lower absorber. In Patent Document 1, when the bending of the lower absorber exceeds a predetermined amount, the upper end of the lower absorber engages with the engagement rib. And thereby, further deformation of the lower absorber is suppressed.
Prior Art Documents
Patent Documents
[0005]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0006] However, in the case of Patent Document 1, it was necessary to form an engagement rib solely to suppress the deformation of the lower absorber. Furthermore, in the case of Patent Document 1, the end of the engagement rib is a free end that is not connected to any other member. Therefore, it was difficult to make the rigidity of the engagement rib and its surroundings sufficiently high, and there was a risk that the deformation around the engagement rib, and consequently the deformation of the lower absorber, could not be sufficiently suppressed.
[0007] Therefore, this specification discloses a vehicle front structure that, despite its simple configuration, can reduce the amount of deformation of the lower absorber during a frontal collision. [Means for solving the problem]
[0008] The vehicle front structure disclosed herein comprises a lower grille and a lower absorber positioned behind the lower grille, wherein the lower grille has a grille opening, a lower wall located below the grille opening, a folded portion that folds back toward the rear of the vehicle from the upper end of the lower wall, and a plurality of vertical columns spaced apart in the vehicle width direction, connecting the folded portion and the upper end of the grille opening, and the lower absorber has a base portion and a front wall rising upward from the front end of the base portion, wherein the gap between the upper end of the front wall and the folded portion is 15 mm or less.
[0009] In this case, the gap between the front wall and the lower wall may be 5 mm or less. Also, the folding distance of the folded portion may be 15 mm or less. Furthermore, the vertical column may be a substantially flat plate shape arranged in a position where its thickness direction is substantially parallel to the vehicle width direction. [Effects of the Invention]
[0010] The technology disclosed herein can effectively reduce the amount of deformation of the lower absorber during a frontal collision. Furthermore, since the technology disclosed herein does not require the formation of ribs more than necessary, the configuration of the lower absorber and lower grille can be simplified. [Brief explanation of the drawing]
[0011] [Figure 1] This is a schematic cross-sectional view of the front of the vehicle. [Figure 2] This is a schematic perspective view of the lower grille. [Figure 3] This is a cross-sectional view of the area around the lower grille. [Figure 4] This is a cross-sectional view of the lower grille and lower absorber of the comparative example. [Figure 5] This is a cross-sectional view of the area around the lower absorber before and after impact. [Modes for carrying out the invention]
[0012] The vehicle's front structure will now be described with reference to the drawings. Figure 1 is a schematic cross-sectional view of the front of the vehicle 10. As is well known, the front of the vehicle 10 is enclosed by a hood 12 and a bumper 14. The hood 12 is a panel member that forms the upper surface of the front of the vehicle. The hood 12 extends from near the lower end of the front windshield glass (not shown) toward the front end of the vehicle 10. This hood 12 is made of a relatively easily deformable panel material. In the event of a collision with a person, the hood 12 will support the person's upper body and absorb the impact by deforming, reducing the load on the person.
[0013] The bumper 14 includes a bumper cover 15 and a lower grille 16. Behind the bumper cover 15 are an elastic member for shock absorption and a reinforcement (not shown) that supports the elastic member.
[0014] A lower grille 16 is located at the bottom of the bumper 14. Figure 2 is a schematic perspective view of the lower grille 16, and Figure 3 is a cross-sectional view of the area around the lower grille 16. As shown in Figure 2, the lower grille 16 has a long, narrow grille opening 18 in the vehicle width direction. In the following, the wall of the lower grille 16 located below the grille opening 18 will be referred to as the "lower wall 20".
[0015] Inside the grille opening 18 are multiple vertical columns 24 and multiple horizontal fins 26. The multiple horizontal fins 26 are spaced apart in the vertical direction. The horizontal fins 26 are substantially flat plate-shaped members that connect the left end and the right end of the grille opening 18. The multiple vertical columns 24 are spaced apart in the vehicle width direction. The vertical columns 24 are substantially flat plate-shaped members that connect the lower end and the upper end of the grille opening 18. The horizontal fins 26 are arranged so that their thickness direction is parallel to the vertical direction, and the vertical columns 24 are arranged so that their thickness direction is parallel to the left-right direction. Therefore, both the horizontal fins 26 and the vertical columns 24 have high rigidity against forces in the longitudinal direction of the vehicle.
[0016] Below the grille opening 18, there is a lower wall 20. As shown in Figure 3, the upper end of this lower wall 20 is folded back towards the rear of the vehicle. Hereafter, this folded-back portion will be referred to as the "folded-back section 22". The vertical column 24 extends upward from the rear end of this folded-back section 22. The vertical column 24, the folded-back section 22, and the lower wall 20 are all integrally molded from resin.
[0017] As shown in Figure 3, a lower absorber 30 is positioned behind the lower wall 20. The lower absorber 30 is a component whose rear end is fixed to a vehicle frame member (for example, a radiator support). This lower absorber 30 shares and supports the load when the bumper 14 collides with an obstacle. The lower absorber 30 has a base portion 32 that extends in the longitudinal direction of the vehicle, and a front wall 34 that rises from the front end of the base portion 32. The front wall 34 is inclined so as it moves forward of the vehicle, it moves upward of the vehicle. This front wall 34 is positioned close behind the lower wall 20. Also, the upper end of the front wall 34 extends to a position close to the folded portion 22. Hereafter, the gap between the front wall 34 and the lower wall 20 will be called the "first gap D1", and the gap between the upper end of the front wall 34 and the folded portion 22 will be called the "second gap D2". In this example, the first gap D1 and the second gap D2 are made as small as possible within the limits necessary for assembling the lower absorber 30. For example, the first gap D1 is 5 mm or less. The second gap D2 is about the size of a human finger, for example, 15 mm or less.
[0018] Also, when the vehicle longitudinal distance from the most forward position of the lower wall 20 to the lower end of the vertical pillar 24 is defined as the "folding distance D3", in this example, this folding distance D3 is also made as small as possible. Specifically, in this example, the folding distance D3 is set to 15 mm or less. In other words, the folding distance D3 is made approximately the same as the second gap D2. The reason for such a configuration will be described.
[0019] Normally, when the vehicle 10 collides with a pedestrian, it is required to appropriately protect the pedestrian's leg. Therefore, conventionally, a test has been conducted in which an impactor 100 simulating the pedestrian's leg is made to collide with the vehicle 10, and the injury value of the pedestrian at the time of the collision is confirmed. The impactor 100 has a bendable joint portion 102, a lower tibia portion 104 connected to the lower side of the joint portion 102, and a thigh portion 106 connected to the upper side of the joint portion 102. In the test, this impactor 100 is made to collide with the front end of the vehicle 10. The two-dot chain line in FIG. 1 shows the behavior of the impactor 100 at the time of the collision. After the collision, as shown by the two-dot chain line, the thigh portion 106 of the impactor 100 falls onto the upper side of the hood 12. Also, in the test, it is required that the lower tibia portion 104 be rebounded forward of the vehicle by the lower absorber 30 early after the collision. This is to suppress excessive elongation of the joint portion 102.
[0020] <000009l>In order to achieve such behavior, after the collision, it is required that the lower absorber 30 does not deform excessively and exerts sufficient reaction force on the lower tibia portion 104. However, depending on the shapes of the lower grill 16 and the lower absorber 30, there are cases where sufficient reaction force cannot be exerted.
[0021] For example, the lower grill 16* and the lower absorber 30* of the comparative example shown in FIG. 4 will be described. Also in this comparative example, the lower grill 16* has a lower wall 20 and a folded-back portion 22. On the other hand, the lower grill 16* of the comparative example has horizontal fins 26 but does not have vertical columns 24. Also, in the case of the lower grill 16* of the comparative example, the folding distance D3 of the folded-back portion 22 is significantly larger than that in this example. Further, in the lower absorber 30* of the comparative example, the gap between the front wall 34 and the lower wall 20 (i.e., the first gap D1) and the gap between the upper end of the front wall 34 and the folded-back portion 22 (i.e., the second gap D2) are both significantly larger than the first gap D1 and the second gap D2 in this example.
[0022] FIG. 5 is a cross-sectional view around the lower absorbers 30, 30* before and after the impactor 100 collides. The right side of FIG. 5 shows the case of this example, and the left side of FIG. 5 shows the case of the comparative example. As shown on the left side of FIG. 5, in the case of the comparative example, with the collision of the impactor 100, the lower grill 16* is greatly crushed and the lower wall 20 moves back significantly. It is considered that the reason for such a large deformation of the lower grill 16* is that there are no vertical columns 24 and the folding distance D3 of the folded-back portion 22 is large. That is, the absence of the vertical columns 24 reduces the rigidity around the grill opening 18, making the walls around the grill opening 18 prone to deformation. Also, it is considered that the large folding distance D3 reduces the rigidity of the folded-back portion 22, making the deformation of the lower wall 20 more likely to occur.
[0023] Furthermore, when the lower wall 20 of the lower grille 16* collides with the front wall 34 of the lower absorber 30* as the impactor 100 collides, the front wall 34 deforms so that its upper end gradually moves upward and backward. In the comparative example, the gap between the upper end of the front wall 34 and the folded portion 22 (i.e., the second gap D2) is large. Therefore, the upward movement of the upper end of the front wall 34 proceeds without restriction. And, along with this movement, the rearward movement of the front wall 34 progresses. As a result, in the comparative example, it is not possible to counteract the impact load from the impactor 100, and a sufficient reaction force cannot be applied to the lower leg portion 104. In this case, the timing of the impactor 100 collapsing toward the vehicle side is delayed, and there is a risk that the amount of elongation of the joint portion 102 will increase.
[0024] On the other hand, in this example, as described above and as shown on the left side of Figure 5, vertical columns 24 are provided to connect the lower and upper ends of the grille opening 18, and the folding distance D3 is sufficiently small. As a result, deformation of the folded portion 22 is less likely to occur, and consequently, deformation of the lower wall 20 can also be suppressed. In particular, by providing the vertical columns 24, vertical deformation of the grille opening 18 is effectively suppressed. Furthermore, these vertical columns 24 are substantially flat in shape, with their thickness direction parallel to the vehicle width direction. With this shape, the vertical columns 24 are less likely to deform when subjected to loads in the longitudinal direction of the vehicle. And by suppressing the deformation of the vertical columns 24, deformation of the grille opening 18 is more effectively prevented. And by preventing deformation of the grille opening 18, deformation of the folded portion 22, which is the lower edge of the grille opening 18, is also effectively suppressed.
[0025] Furthermore, in this example, since the front wall 34 is positioned close to the lower wall 20, the lower wall 20 collides with the front wall 34 early after the impact of the impactor 100. Then, a portion of the load is transmitted to the front wall 34, and subsequently to the lower absorber 30, thereby suppressing further deformation of the lower wall 20.
[0026] Furthermore, in this example, the distance between the upper end of the front wall 34 and the folded portion 22, i.e., the second gap D2, is small. Therefore, as the front wall 34 retracts, when the upper end of the front wall 34 moves upward, it comes into contact with the folded portion 22 early on. This contact suppresses the upward movement of the front wall 34, and consequently, the backward movement of the front wall 34. As a result, the amount of backward movement of the lower absorber 30 is reduced, generating a large reaction force on the lower leg portion 104 of the impactor 100. This causes the lower leg portion 104 to bounce forward, and the thigh portion 106 to collapse into the hood 12 early on. Consequently, excessive extension of the joint portion 102 is effectively prevented.
[0027] As is clear from the above explanation, in this example, a vertical column 24 is provided extending upward from the folded portion 22, and the second gap D2, which is the gap between the front wall 34 of the lower absorber 30 and the folded portion 22, is set to 15 mm or less. This effectively reduces the amount of deformation of the lower absorber 30 during a frontal impact. Note that the configuration described so far is just one example, and other configurations may be changed as appropriate as long as the configuration of claim 1 is met. For example, in the above explanation, in addition to the vertical column 24, a horizontal fin 26 is also provided in the grill opening 18, but the horizontal fin 26 is not required. Also, the vertical column 24 may have other shapes as long as it connects the folded portion 22 to the upper edge of the grill opening 18. For example, the vertical column 24 is not limited to a straight line, but may have a wave shape that repeatedly curves in the left-right direction as it moves upward. [Explanation of symbols]
[0028] 10 Vehicle, 12 Hood, 14 Bumper, 15 Bumper cover, 16, 16* Lower grille, 18 Grille opening, 20 Lower wall, 22 Folded section, 24 Vertical column, 26 Horizontal fin, 30, 30* Lower absorber, 32 Base section, 34 Front wall, 100 Impactor, 102 Joint section, 104 Lower leg section, 106 Thigh section.
Claims
1. Lower grille and A lower absorber positioned behind the lower grille, Equipped with, The aforementioned lower grille is Grille opening and, The lower wall located below the grill opening, A folded portion that folds back from the upper end of the lower wall towards the rear of the vehicle, Multiple vertical columns are arranged at intervals in the vehicle width direction, and the multiple vertical columns connect the folded portion and the upper end of the grille opening, It has, The lower absorber is, The base part, A front wall rising upward from the front end of the base portion, The gap between the upper end of the front wall and the folded portion is 15 mm or less. A vehicle front structure characterized by the following features.
2. The vehicle front structure according to claim 1, A vehicle front structure characterized in that the gap between the front wall and the lower wall is 5 mm or less.
3. The vehicle front structure according to claim 1, The front structure of a vehicle is characterized in that the folding distance of the aforementioned folded portion is 15 mm or less.
4. The vehicle front structure according to claim 1, The front structure of a vehicle is characterized in that the vertical columns are substantially flat and arranged in a position where their thickness direction is substantially parallel to the vehicle width direction.