Vehicle front structure

Abstract

To provide a vehicle front structure which can achieve pedestrian protection performance and inhibit damage of vehicle components during a light collision even if a plate member is adopted in a beam member having closed cross sections.SOLUTION: A vehicle front structure comprises: a beam member 24 having closed cross sections 25, 26; and a plate member 30 extending forward from the beam member 24. The plate member 30 comprises: a vertical surface portion 31 along a front surface of the beam member 24; a body portion 33 extending forward from the vertical surface portion 31; a front end portion 34 positioned at a front end of the body portion 33 and configured to have higher rigidity against a load applied in an anteroposterior direction than that of the body portion 33; and a protrusion surface portion 35 spaced apart from the vertical surface portion 31 in a forward direction. The front end portion 34 comprises: an upper section 34U located at a higher level than the body portion 33. The protrusion surface portion 35 comprises: a protrusion-surface-portion upper section 35U located at a higher level than an upper end of the upper section 34U; and a protrusion-surface-portion lower section 35L located at a lower level than the upper end of the upper section 34U. The protrusion-surface-portion lower section 35L is configured to have lower strength against a collision load applied from the front than the protrusion-surface-portion upper section 35U.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a front structure of a vehicle, and more particularly to a front structure of a vehicle that includes a beam member having a closed cross section that is located in front of the vehicle from a subframe and extends in the vehicle width direction, and a plate member that extends from the beam member in the front direction of the vehicle. [Background technology]

[0002] Conventionally, the following structure has been known as a front structure for a vehicle. That is, a pair of left and right extension members are provided at the front of a subframe (similar to a suspension cross member), a sheet metal beam member is attached to the front of these left and right extension members via a lower crash can, and a plate member such as a lower stiffener (a so-called leg sweep member) is provided at the front of the beam member.

[0003] In this conventional vehicle front structure, the plate members deform and the sheet metal beam members bend during a collision with a pedestrian, achieving both the generation of an appropriate reaction force and energy absorption performance, and also preventing unexpected damage to vehicle components such as cooling members, even in the event of a minor collision.

[0004] However, when this conventional vehicle structure is subjected to the MPDB crash test that is scheduled to be introduced in the near future, there is a problem in that the part corresponding to the lower crash can will cause damage to the other vehicle. Here, the MPDB crash test is a crash test using a Mobile Progressive Deformable Barrier (a forward-moving deformable barrier) to evaluate the damage caused to the other vehicle.

[0005] Therefore, instead of the conventional beam members made of sheet metal, it is possible to adopt a highly rigid beam member with a closed cross section, and to adopt a resin plate member disclosed in Patent Document 1 as the above-mentioned plate member.

[0006] In this case, when the vehicle is involved in a minor collision, the crushed plate member accumulates at the bottom of the beam member, causing the beam member to rotate about its widthwise axis without deformation, and the lower crash can to bend and deform without axial compression.

[0007] This can result in unexpected contact with surrounding vehicle components such as cooling components. In addition, when protecting a pedestrian, the high-rigidity beam member does not deform, so there is a risk that the injury value will increase due to excessive reaction force. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-265399 Summary of the Invention [Problem to be solved by the invention]

[0009] Therefore, the object of this invention is to provide a front structure for a vehicle that can achieve both pedestrian protection performance and suppression of damage to vehicle parts in the event of a minor collision, even when a plate member is used for a beam member having a closed cross section. [Means for solving the problem]

[0010] The present invention provides a front structure for a vehicle comprising: a beam member having a closed cross section that is located in front of the vehicle of the subframe and extends in the vehicle width direction; and a plate member extending from the beam member in the front direction of the vehicle, wherein the plate member comprises a vertical surface portion that is provided along the front portion of the beam member, a main body portion that extends from the vertical surface portion in the front direction of the vehicle, a front end portion at the front end of the main body portion that is configured to be more rigid against longitudinal loads than the main body portion, and a protruding surface portion that is spaced away from the vertical surface portion in the front direction of the vehicle, wherein the front end portion has a front end upper portion that is located above the main body portion, and the protruding surface portion has a protruding surface upper portion that is located above the upper end of the front end upper portion and a protruding surface lower portion that is located below the upper end of the front end upper portion, and the protruding surface lower portion is configured to have lower strength against impact loads from the front of the vehicle compared to the protruding surface upper portion.

[0011] With this invention, when a pedestrian is hit from any direction, the front end portion transmits the load to the main body portion, and by allowing the main body portion to deform under a constant load, an appropriate reaction force can be generated.

[0012] Furthermore, in the event of a frontal collision, even if the front end portion moves backward due to a rearward load and a crushed residue remains in the lower portion of the protruding surface portion, the lower portion of the protruding surface portion is configured to have lower strength against impact loads from the front of the vehicle compared to the upper portion of the protruding surface portion, so the lower portion of the protruding surface portion can deform rearward, and the entire surface of the beam member moves almost straight rearward due to the crushed residue of the front end portion that is contained within the upper portion of the protruding surface portion of the protruding surface portion that protrudes forward and the lower portion of the protruding surface portion that has deformed rearward, thereby suppressing the rotational behavior of the beam member. In short, even if a plate member is used for a beam member having a closed cross section, it is possible to achieve both pedestrian protection performance and suppression of damage to vehicle parts in the event of a minor collision.

[0013] In one aspect of the present invention, the protruding surface portion is provided on a part of the vertical surface portion and is formed into a box shape with an upper wall and left and right side walls, a high rigidity portion is arranged in the upper region of the box shape, and the lower region is formed as a hollow.

[0014] The high rigidity portions described above may be vertical ribs extending in the up-down direction, or may be other high rigidity portions such as horizontal ribs or diagonal ribs as long as they are means for improving rigidity. According to this invention, a structure in which the lower portion of the protruding surface portion has lower strength against a front impact load than the upper portion of the protruding surface portion can be realized with a simple configuration.

[0015] In one aspect of the present invention, a lower crash can connected to the beam member is provided in front of the subframe, and the beam member has a central portion located on the vehicle width direction center side and extending along the vehicle width direction, and a pair of central portions extending from both left and right ends of the central portion in the vehicle width direction to the outer sides in the vehicle width direction. but Rear of the vehicle It is tilted to and both end portions, and the protruding surface portion may be provided between a boundary portion between the central portion and the both end portions and an inner end position in the vehicle width direction of the lower crash can. According to this invention, when the vehicle enters the barrier, the protruding surface portion hits the barrier before the vertical surface portion hits the barrier, so that the collapse behavior can be controlled.

[0016] In one aspect of the present invention, the center of the box shape of the protruding surface portion in the vehicle width direction may protrude forward of the vehicle. According to this invention, the forwardly protruding portion of the box shape hits the barrier first, and the entire surface of the protruding surface can be crushed substantially uniformly.

[0017] In one aspect of the present invention, the front end portion has a front end upper portion located above the main body portion and a front end lower portion located below the main body portion, and the front end upper portion is located further forward of the vehicle than the front end lower portion and is located further from the main body portion. Up and down The protrusion height may be increased.

[0018] With this invention, in the event of a frontal collision, the upper end of the front end portion can be made to rotate downward as it moves rearward, which causes the main body portion to bend downward and displace the remaining crushed portion of the front end portion downward in the vertical surface portion.

[0019] As an aspect of the present invention, a rib may be provided connecting the front end of the front end portion and the main body portion. According to the present invention, the front end portion can be formed to have high rigidity with a simple structure. [Effects of the Invention]

[0020] According to this invention, even if a plate member is used for a beam member having a closed cross section, it is possible to achieve both pedestrian protection performance and suppression of damage to vehicle parts in the event of a minor collision. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 2 is a top perspective view showing the front structure of the vehicle. [Figure 2] FIG. 2 is a bottom perspective view showing the front structure of the vehicle. [Figure 3] FIG. 4 is a perspective view showing the plate member as viewed from below and behind the vehicle. [Figure 4] FIG. 4 is a plan view showing the beam member, the plate member, and the lower crash can. [Figure 5] FIG. 5 is an enlarged plan view of the center portion in the vehicle width direction of FIG. 4. [Figure 6] 4. (a) is a cross-sectional view taken along line AA in FIG. 4, (b) is a cross-sectional view taken along line BB in FIG. 4, and (c) is a cross-sectional view taken along line CC in FIG. [Figure 7] FIG. [Figure 8] 8 is a perspective view showing a cross section of the main part of FIG. 7 taken in the vertical direction. [Figure 9] FIG. 10 is a partial plan view showing the relationship between the barrier and the protruding surface portion in a determined collision mode. [Figure 10] FIG. 2 is a schematic side view showing the first stage of deformation behavior during a frontal collision. [Figure 11] FIG. 10 is a schematic side view showing the second stage of deformation behavior during a frontal collision. [Figure 12] FIG. 10 is a schematic side view showing the deformation behavior in the third stage during a frontal collision. [Figure 13] FIG. 10 is a schematic side view showing the deformation behavior in the fourth stage during a frontal collision. DETAILED DESCRIPTION OF THE INVENTION

[0022] The objective of achieving both pedestrian protection performance and suppression of damage to vehicle parts in the event of a minor collision, even when a plate member is used for a beam member having a closed cross section, is achieved by a structure comprising: a beam member having a closed cross section that is located in front of the vehicle of the subframe and extends in the vehicle width direction; and a plate member extending from the beam member towards the front of the vehicle, the plate member comprising: a vertical surface portion provided along the front portion of the beam member; a main body portion extending from the vertical surface portion towards the front of the vehicle; a front end portion at the front end of the main body portion that is configured to be more rigid against longitudinal loads than the main body portion; and a protruding surface portion spaced away from the vertical surface portion towards the front of the vehicle, the front end portion having a front end upper portion located above the main body portion, and the protruding surface portion having a protruding surface upper portion located above the upper end of the front end upper portion and a protruding surface lower portion located below the upper end of the front end upper portion, the protruding surface lower portion being configured to be less strong against impact loads from the front of the vehicle than the protruding surface upper portion. [Example]

[0023] An embodiment of the present invention will be described in detail below with reference to the drawings. The drawings show the front structure of a vehicle, with Fig. 1 being a top perspective view showing the front structure of the vehicle, Fig. 2 being a bottom perspective view showing the front structure of the vehicle, Fig. 3 being a perspective view showing the plate member as seen from the rear and below the vehicle, and Fig. 4 being a plan view showing the beam member, plate member, and lower crash can.

[0024] Fig. 5 is an enlarged plan view of the central portion in the vehicle width direction of Fig. 4, Fig. 6(a) is a cross-sectional view taken along line AA in Fig. 4, Fig. 6(b) is a cross-sectional view taken along line BB in Fig. 4, Fig. 6(c) is a cross-sectional view taken along line CC in Fig. 4, Fig. 7 is a perspective view showing the notch and the protruding surface portion, and Fig. 8 is a perspective view showing a cross-section of the main portion of Fig. 7 in the vertical direction. Furthermore, Fig. 9 is a partial plan view showing the relationship between the barrier and the protruding surface portion in a determined collision mode.

[0025] As shown in FIG. 1, a dash lower panel (dash panel) 1 is provided to separate the engine compartment (motor compartment) from the passenger compartment in the longitudinal direction of the vehicle, and front side frames 3 are provided extending forward from both left and right sides of a tunnel section 2 formed in this dash lower panel 1 in the vehicle width direction.

[0026] The front side frame 3 described above is a vehicle body rigidity member having a front side frame inner and a front side frame outer joined and fixed together, and having a front side closed cross section extending in the longitudinal direction of the vehicle.

[0027] Upper crash cans 6 (collision energy absorbing members) extending in the longitudinal direction of the vehicle are attached to the front ends of the front side frames 3 via plate-shaped set plates 4 and plate-shaped mounting plates 5. As shown in Figures 1 and 2, the upper crash cans 6 are attached to the front ends of the left and right front side frames 3, respectively, and bumper reinforcements 7 extending in the vehicle width direction are attached to the front ends of the pair of left and right upper crash cans 6.

[0028] As shown in FIG. 1, the above-mentioned bumper reinforcement 7 is composed of two members: a plate-shaped bumper plate 7a located on the front side, and a bumper beam 7b with a closed cross-section structure located on the rear side. This bumper reinforcement 7 extends in the vehicle width direction in front of the upper crash can 6.

[0029] 1, an apron reinforcement 8 extending in the front-to-rear direction of the vehicle is provided above the front side frame 3 and at a position on the outer side of the front side frame 3 in the vehicle width direction. This apron reinforcement 8 is a vehicle body strength member having an apron reinforcement closed cross section extending in the front-to-rear direction of the vehicle, and the rear portion of this apron reinforcement 8 is directly or indirectly connected to the hinge pillar. This hinge pillar is a vehicle body strength member having a hinge pillar closed cross section extending in the vertical direction of the vehicle, with an inner hinge pillar and an outer hinge pillar joined and fixed together.

[0030] 1, a shroud upper panel 9 is provided to connect the front ends of a pair of left and right apron reinforcements 8, 8 in the vehicle width direction. In this embodiment, the shroud upper panel 9 is formed of three members: a shroud upper central portion 9a located in the center of the vehicle width direction, and shroud upper side portions 9b, 9c located on both the left and right sides in the vehicle width direction.

[0031] As shown in Figures 1 and 2, a connecting member 10 is provided to connect the front portion of the front side frame 3 located on the lower side to the shroud upper panel 9 and apron reinforcement 8 located on the upper side in the vertical direction.

[0032] 1 and 2, a suspension housing 11 is provided between the upper apron reinforcement 8 and the lower front side frame 3 to vertically connect these two members 8, 3. This suspension housing 11 is equipped with a front suspension tower portion 12.

[0033] On the other hand, as shown in FIG. 1, a dash lower panel reinforcing member 13 is joined and fixed to the front portion of the dash lower panel 1, and a dash lower closed cross section is formed between this dash lower panel reinforcing member 13 and the dash lower panel 1 along the longitudinal direction of the dash lower panel reinforcing member 13.

[0034] The dash lower panel reinforcing member 13 described above is formed integrally at the front end of the tunnel section 2 with an arch-shaped section 13a formed in an arch shape that follows the shape of the tunnel section 2, and a horizontal section 13b that extends approximately horizontally from the lower end of this arch-shaped section 13a outward in the vehicle width direction.

[0035] As shown in FIGS. 1 and 2, a subframe 14 (which also serves as a suspension cross member) is provided below the engine compartment. This subframe 14 is composed of a front cross member 15 as the subframe main body, a rear cross member 16 (see Figure 1) located rearward of the front cross member 15 and extending in the vehicle width direction, and left and right side members 17, 17 that connect the front cross member 15 and rear cross member 16 in the fore-and-aft direction of the vehicle, all connected in a frame-like manner when viewed from above the vehicle.

[0036] The front cross member 15 has a front portion extending in the vehicle width direction, and both left and right side portions of the front cross member 15 extend in the vehicle longitudinal direction. The left and right side members 17 also extend in the vehicle longitudinal direction.

[0037] 1 and 2, a suspension arm support bracket 18 that supports the vehicle body side end of a front suspension arm (not shown) is attached to the front portion of the side member 17. Also, as shown in the figures, an extension member 19 is provided at the front end of the side member 17, extending from the front end toward the front of the vehicle.

[0038] The extension member 19 is formed into a cylindrical shape with a closed cross section between the upper and lower members by combining an upper member and a lower member with a two-part structure, and is configured so that the width of the extension member 19 in the vehicle width direction at the front is wider than the width of the extension member 19 in the vehicle width direction at the rear.

[0039] The extension members 19 are provided at the front end portions of the pair of left and right side members 17, respectively, and a cross member 20 extending in the vehicle width direction is provided between the front portions of the pair of left and right extension members 19, 19.

[0040] 2, lower crash cans 23 (collision energy absorbing members) extending in the front-rear direction of the vehicle are attached to the front end of each of the extension members 19 via a plate-shaped set plate 21 and a plate-shaped mounting plate 22. Beam members 24 (specifically, perimeter beams) extending in the vehicle width direction are attached to the front ends of the pair of left and right lower crash cans 23.

[0041] 6, the beam member 24 is formed by combining a front wall 24a, a rear wall 24b, an upper wall 24c, and a lower wall 24d in the shape of a rectangular frame, and a partition wall 24e is integrally formed between the front wall 24a and the rear wall 24b, parallel to the upper and lower walls 24c, 24d, thereby forming two closed cross sections 25, 26. The beam member 24 can be made of an extruded member made of aluminum or an aluminum alloy.

[0042] That is, as shown in Fig. 2, the beam member 24 is a member having closed cross sections 25, 26 that are located in front of the subframe 14 and extend in the vehicle width direction. Furthermore, as shown in Fig. 4, the beam member 24 has a central portion 27 that is located toward the center in the vehicle width direction and extends along the vehicle width direction, and both end portions 28 that are inclined toward the rear of the vehicle from both left and right ends of the central portion 27 in the vehicle width direction (see boundary portion β described later) toward the outside in the vehicle width direction.

[0043] As shown in FIGS. 1, 2 and 6, a lower stiffener 30 is provided as a plate member extending from the beam member 24 toward the front of the vehicle. The lower stiffener 30 is made of resin, and its front end extends to a position adjacent to the back surface of the front bumper face (not shown). The lower stiffener 30 is a so-called leg sweep member that pushes back the pedestrian's ankles to prevent them from getting caught under the vehicle when the vehicle comes into contact with (collides with) the pedestrian.

[0044] As shown in Figures 3, 4 and 6, the above-mentioned lower stiffener 30 includes a vertical surface portion 31 provided along the front portion of the beam member 24, a plurality of fixing portions 32 that fix this vertical surface portion 31 to the beam member 24, a main body portion 33 that extends forward of the vehicle from the vertical surface portion 31 including the fixing portions 32, and a front end portion 34 that is configured at the front end of the main body portion 33 to have higher rigidity against longitudinal loads than the main body portion 33.

[0045] As shown in the figure, the lower stiffener 30 also has a protruding surface portion 35 that is spaced away from the vertical surface portion 31 toward the front of the vehicle. As shown in Figures 3 and 6, the above-mentioned vertical surface portion 31 extends in the vertical direction in a side view, and as shown in Figure 4, in a plan view, it is formed so as to follow the front surface of the central portion 27 located on the center side of the beam member 24 in the vehicle width direction, and the front surfaces of both end portions 28 that slope from the central portion 27 toward the rear of the vehicle.

[0046] As shown in Fig. 3, a plurality of (six in this embodiment) fixing portions 32 for fixing the vertical surface portion 31 to the beam member 24 are provided on the vertical surface portion 31 at intervals in the vehicle width direction. The number of fixing portions 32 is not limited to six, and may be more than six or less than six. The fixing portions 32 are fixed to the front portion of the beam member 24 using a plurality of fixing members 36 shown in Fig. 1.

[0047] 6, the main body portion 33 extends toward the front of the vehicle substantially perpendicularly from the vertical surface portion 31 including the fixing portion 32. Also, as shown in the figure, the main body portion 33 is formed in a linear shape when viewed from the side of the vehicle.

[0048] As shown in Figure 6, the front end portion 34, which is constructed to have higher rigidity against longitudinal loads than the main body portion 33, includes a rear inclined piece portion 37 extending downward and forward from the front end of the main body portion 33, a front inclined piece portion 38 extending upward and forward from the lower end of the rear inclined piece portion 37, and a front piece portion 39 extending approximately directly upward from the upper end of the front inclined piece portion 38.

[0049] That is, the front end portion 34 is made up of the pieces 37, 38, and 39 as shown by the imaginary line in FIG. 6(a). Moreover, as shown in Figure 6, the above-mentioned front end portion 34 has a front end upper portion 34U located above the main body portion 33 and a front end lower portion 34L located below the main body portion 33, and the front end upper portion 34U is located further forward of the vehicle than the front end lower portion 34L.

[0050] In this embodiment, the front end upper portion 34U is made up of the front piece 39, and the front end lower portion 34L is made up of both the rear inclined piece 37 and the front inclined piece 38. As a result, even if a collision occurs with a pedestrian from any direction, the front end portion 34 transmits the load to the main body portion 33, allowing the main body portion 33 to deform under a constant load, and generating an appropriate reaction force.

[0051] In addition, during a frontal collision, load is input to the front upper portion 34U of the front end 34 before the front lower portion 34L, so a moment is generated that tends to rotate the upper end of the front end 34 downward toward the rear, causing the main body 33 to deform downward, thereby preventing the main body 33 from being crushed on the front surface of the beam member 24.

[0052] In short, even when the lower stiffener 30 is used on the beam member 24 having closed cross sections 25, 26, it is configured to achieve both pedestrian protection performance and suppression of damage to vehicle components (e.g., cooling components) in the event of a minor collision.

[0053] Furthermore, as shown in Figure 6, the front end portion 34 has a front end lower portion 34L that protrudes downward from the front end of the main body portion 33, and a front end of this front end lower portion 34L, more specifically, a front end upper portion 34U that is located at the front end of the front inclined piece portion 38. As a result, the boundary α between the front end of the main body 33 and the rear end of the front end lower portion 34L is configured to be a bending point that causes the front end 34 to rotate in the event of a frontal collision.

[0054] 6, the front end portion 34 is configured to have a forward-inclined shape with a high front and a low rear, so that the front portion is high and the rear portion is low. As a result, the front end portion 34 is inclined forward in a so-called upward-forward direction, and the moment that tends to rotate the upper end of the front end portion 34, more specifically the upper end of the front piece portion 39, downward as it moves rearward increases, thereby ensuring that the main body portion 33 deforms downward.

[0055] In addition, the forward tilt structure allows the front end portion 34 to increase the stroke of rotation backward, thereby suppressing interference of the front end portion 34 with the main body portion 33 and preventing the front end portion 34 from bottoming out.

[0056] 3 and 6(a), a claw portion 40 that protrudes toward the rear of the vehicle and is inserted into a hole 24f formed in the front wall 24a of the beam member 24 is integrally formed on the back surface of the vertical surface portion 31 of the lower stiffener 30 in the vehicle width direction central portion. By inserting this claw portion 40 into the hole 24f, the lower stiffener 30 is temporarily fixed and positioned when assembling the lower stiffener 30 to the beam member 24.

[0057] As shown in Figures 4, 5, and 6, a rib 41 is provided that connects the front end of the front end portion 34 and the front end of the main body portion 33. As shown in Figure 6(c), the rib 41 has a front piece, a rear piece, a lower piece, and an upper piece, and the front piece of the rib 41 is in contact with the back surface of the front piece portion 39 of the front end portion 34, the rear piece of the rib 41 is in contact with the front surface of the rear inclined piece portion 37, and the lower piece of the rib 41 is in contact with the upper surface of the front inclined piece portion 38, and the upper piece of the rib 41 is inclined in a front-high, rear-low manner so as to connect the upper end of the front piece portion 39 and the front end of the main body portion 33. This rib 41 is formed integrally with the front end portion 34.

[0058] 4, a plurality of the ribs 41 are provided at predetermined intervals in the vehicle width direction of the lower stiffener 30. This allows the front end portion 34 to be formed with high rigidity using a simple structure.

[0059] Here, the above-mentioned lower stiffener 30 is configured to control the reaction force to the pedestrian by dividing the functions between the highly rigid front end portion 34, which is the part that receives the load, and the main body portion 33, which is the part that deforms.

[0060] As shown in Fig. 5, which is an enlarged view of the center portion in the vehicle width direction of Fig. 4, the rib 41 of the front end portion 34 is inclined outward in the vehicle width direction toward the rear of the vehicle at a position corresponding to the center portion 27 of the beam member 24. In Fig. 5, an imaginary extension line indicating the inclination direction of the rib 41 is added to clarify the inclination direction of the rib 41.

[0061] In this way, by inclining the rib 41 of the front end portion 34 corresponding to the center portion 27 of the beam member 24 outward in the vehicle width direction toward the rear of the vehicle, the rib 41 does not remain crushed during a frontal collision. If the rib were to extend straight in the front-to-rear direction, the rib would be stretched and would remain crushed, but by inclining the rib 41 as described above, the collapse of the rib 41 is promoted, thereby preventing the rib from remaining crushed.

[0062] 5, the rib 41 located to the right of the vehicle width centerline 30CL of the lower stiffener 30 in the vehicle width direction is inclined outward to the right in the vehicle width direction toward the rear of the vehicle, and the rib 41 located to the left of the vehicle width centerline 30CL in the vehicle width direction is inclined outward to the left in the vehicle width direction toward the rear of the vehicle. This is configured to prevent the rib 41 from remaining uncrushed.

[0063] 2, 3 and 6(c), the main body portion 33 of the lower stiffener 30 is formed linearly in the vehicle longitudinal direction, and lower ribs 42 that connect the vertical surface portion 31 including the fixing portion 32 to the front end portion 34 are provided on the underside of the main body portion 33 of the lower stiffener 30. In this embodiment, a plurality of lower ribs 42 that connect the front end portion 34 to the vertical surface portion 31 in the vehicle longitudinal direction are provided at intervals in the vehicle width direction on the underside of the main body portion 33 at positions that correspond to both end portions 28 of the beam member 24 in the vehicle longitudinal direction.

[0064] However, at the position where the under-cover mounting portion (see 43 shown in Figures 7 and 8) described later is provided, the above-mentioned lower rib 42 is provided on the underside of the main body portion 33 so as to connect the front end portion 34 and the under-cover mounting portion 43 in the fore-and-aft direction of the vehicle.

[0065] This allows the reaction force when protecting a pedestrian to be adjusted by the lower ribs 42. More specifically, by changing the number of lower ribs 42 and the thickness of the lower ribs 42, the reaction force when protecting a pedestrian can be adjusted as desired.

[0066] Furthermore, the lower rib 42 improves the rigidity of the main body 33, so that in the event of a frontal collision, the main body 33 is reliably deflected downward without buckling or bending. Furthermore, as shown in FIG. 6(c), the lower end of the lower rib 42 is located higher than the lower end of the front end lower portion 34L of the front end portion 34.

[0067] This prevents the lower rib 42 from interfering with the rotation of the front end 34 during a frontal collision, and also enables the lower rib 42 to adjust the collision reaction force when protecting a pedestrian.

[0068] 2 and 3, an under-cover mounting portion 43 extending downward from the base (i.e., root portion) of the main body portion 33 of the lower stiffener 30 is provided. As shown in the figures, a plurality of under-cover mounting portions 43 are provided at intervals in the vehicle width direction.

[0069] As shown in Figures 7 and 8, the under-cover mounting portion 43 includes a pair of left and right side walls 43a, 43a facing each other and spaced apart in the vehicle width direction, a front wall 43b connecting the front ends of the pair of left and right side walls 43a in the vehicle width direction, and a bottom wall 43c connecting the lower ends of the pair of left and right side walls 43a in the vehicle width direction.

[0070] The under-cover mounting portion 43 is configured in a box shape that is open to the rear and upper sides of the vehicle by the walls 43a, 43b, 43c. The bottom wall 43c of the under-cover mounting portion 43 serves as a mounting seat for mounting the under-cover 50 shown in FIGS.

[0071] 6(c), 7, and 8, a notch 44 is formed in the base of the under-cover mounting portion 43. As shown in FIGS. 7 and 8, the notch 44 is formed by cutting out the lower side of the vertical surface portion 31, corresponding to the space between the upper portions of the pair of left and right side walls 43a of the under-cover mounting portion 43.

[0072] This makes the notch 44 a weak part, and by folding the main body part 33 downward from the notch 44 as a starting point, i.e., with the base as a fulcrum, the remaining position on the tip side of the main body part 33 is moved downward.

[0073] As shown in Figures 4 and 9, the above-mentioned protruding surface portion 35 is provided on a part of the vertical surface portion 31, and the protruding surface portion 35 is formed in a box shape with an upper wall 35a and left and right side walls 35b, 35b. In other words, the protruding surface portion 35 is formed on the vertical surface portion 31 via the upper wall 35a and the left and right side walls 35b, 35b so as to be spaced away from the vertical surface portion 31 toward the front of the vehicle. As shown in Figures 7 and 8, the rear and lower sides of the protruding surface portion 35 are open.

[0074] Moreover, as shown in Figure 6(b), the above-mentioned protruding surface portion 35 has a protruding surface portion upper portion 35U located above the upper end of the front end portion upper portion 34U, and a protruding surface portion lower portion 35L located below the upper end of the front end portion upper portion 34U.

[0075] In this embodiment, as shown in FIG. 6(b), the protruding surface portion lower portion 35L is set at the same height in the vehicle vertical direction as the front end portion upper portion 34U. The protruding surface portion lower portion 35L is configured to have lower strength against impact loads from the front of the vehicle than the protruding surface portion upper portion 35U.

[0076] Specifically, as shown in Figures 6(b), 7 and 8, a plurality of vertical ribs 45 extending in the vertical direction as a high rigidity portion are arranged in the upper region of the box shape (i.e., the region of the upper portion 35U of the protruding surface portion), and a cavity 46 is formed in the lower region of the box shape (i.e., the region of the lower portion 35L of the protruding surface portion).

[0077] As a result, even if the front end portion 34 moves back due to a rearward load during a vehicle frontal collision and the lower portion 34L of the front end portion remains crushed, the entire surface of the beam member 24 moves straight backward due to the upper portion 35U of the protruding surface portion 35 that protrudes forward, thereby suppressing the rotational behavior of the beam member 24.

[0078] In addition, by arranging vertical ribs 45 in the upper region of the box shape and making the lower region a cavity 46, a structure is realized with a simple configuration in which the lower portion 35L of the protruding surface portion has lower strength against impact loads from the front compared to the upper portion 35U of the protruding surface portion.

[0079] 7 and 8, a plurality of the vertical ribs 45 are provided at intervals in the vehicle width direction. The vertical ribs 45 extend downward from the upper wall 35a of the protruding surface portion 35, and the lower portions of the vertical ribs 45 are supported by horizontal struts 47 that are horizontally supported between a pair of left and right side walls 35b, 35b of the protruding surface portion 35.

[0080] 4, the protruding surface portion 35 is provided in a position on the lower stiffener 30 that corresponds, in the vehicle width direction, to a boundary β between the central portion 27 and both end portions 28 of the beam member 24 and the vehicle width direction inner end position of the lower crash can 23. In this embodiment, the protruding surface portion 35 is provided in a position adjacent to the vehicle width direction inner end position of the lower crash can 23.

[0081] As a result, when the barrier bar intrudes in a collision mode determined by the MPDB collision test (see Figure 9), the protruding surface portion 35 hits the barrier bar before the vertical surface portion 31, making it possible to control the collapse behavior.

[0082] 4 and 9, the center of the box shape of the protruding surface portion 35 in the vehicle width direction protrudes forward of the vehicle, forming a central protruding portion 35c. As a result, in the event of a frontal collision, the forward protruding portion of the box shape (see central protruding portion 35c) hits the barrier BAR (see FIG. 9) first, causing the entire surface of the protruding surface portion 35 to be crushed almost uniformly.

[0083] On the other hand, as shown in FIG. 6, the front end portion 34 has a front end upper portion 34U located above the main body portion 33 and a front end lower portion 34L located below the main body portion 33. The above-mentioned upper front end portion 34U is located further forward of the vehicle than the lower front end portion 34L, and is formed to protrude higher from the main body portion 33.

[0084] This allows the upper end of the front end portion 34 to rotate downward toward the rear during a frontal collision, causing the main body portion 33 to deform downward and displacing the remaining crushed portion of the front end portion 34 downward on the vertical surface portion 31.

[0085] FIG. 10 is a schematic side view showing the deformation behavior in the first stage during a frontal collision, FIG. 11 is a schematic side view showing the deformation behavior in the second stage during a frontal collision, FIG. 12 is a schematic side view showing the deformation behavior in the third stage during a frontal collision, and FIG. 13 is a schematic side view showing the deformation behavior in the fourth stage during a frontal collision. Next, the deformation behavior during a frontal collision will be described with reference to FIGS.

[0086] <Deformation behavior in the first stage shown in Figure 10> In the first stage of a frontal collision, the frontal collision load is input to the front upper portion 34U of the front end portion 34 of the lower stiffener 30 before it is input to the front lower portion 34L, causing the upper end of the front end portion 34 to rotate downward and rearward, with the boundary portion α as a fulcrum, as shown by arrow a in FIG. 10, and this moment causes the main body portion 33 to deform downward as shown by arrow b in FIG. 10.

[0087] <Deformation behavior in the second stage shown in Figure 11> Because the base of the main body 33 of the lower stiffener 30 is weakened by the notch 44, in the second stage of a frontal collision, the main body 33 is folded downward with the base, or root, of the main body 33 as a fulcrum, and the remaining position of the front end 34 moves downward, as shown in Figure 11. Also, so as not to impede the downward movement of the main body 33, the under-cover mounting portion 43 is rotated rearward with the formation portion of the notch 44 as a fulcrum.

[0088] <Deformation behavior in the third stage shown in Figure 12> By providing a member (see the protruding surface portion 35 and the vertical rib 45 of its upper portion 35U) at the rear of the lower stiffener 30 with a crushed remaining amount substantially equal to that of the front end portion 34 of the lower stiffener 30 moving rearward, the crushed remaining amount on the front side of the beam member 24 becomes substantially uniform in the third stage of a frontal collision, as shown in FIG. 12.

[0089] <Deformation behavior at the fourth stage shown in Figure 13> Due to the above-described equalization, in the fourth stage of a frontal collision, the beam member 24 moves straight rearward, causing the lower crash can 23 to be axially compressed, thereby appropriately absorbing the collision energy.

[0090] In the figure, arrow F indicates the front of the vehicle, arrow R indicates the rear of the vehicle, arrow IN indicates the inside in the vehicle width direction, arrow OUT indicates the outside in the vehicle width direction, and arrow UP indicates the top of the vehicle.

[0091] As described above, the vehicle front structure according to this embodiment comprises the beam member 24, which is located in front of the subframe 14 and has closed cross sections 25, 26 extending in the vehicle width direction, and the plate member (see lower stiffener 30) extending from the beam member 24 towards the front of the vehicle, and the plate member (lower stiffener 30) comprises a vertical surface portion 31 provided along the front surface of the beam member 24, a main body portion 33 extending from the vertical surface portion 31 towards the front of the vehicle, a front end portion 34 at the front end of the main body portion 33 and configured to have higher rigidity against longitudinal loads than the main body portion 33, and a protruding surface portion 35 spaced from the vertical surface portion 31 toward the front of the vehicle, the front end portion 34 having a front end upper portion 34U located above the main body portion 33, the protruding surface portion 35 having a protruding surface upper portion 35U located above the upper end of the front end upper portion 34U and a protruding surface lower portion 35L located below the upper end of the front end upper portion 34U, the protruding surface lower portion 35L being characterized by being configured to have lower strength against impact loads from the front of the vehicle compared to the protruding surface upper portion 35U (see Figures 1, 2 and 6).

[0092] With this type of front structure of the vehicle, even if a collision occurs with a pedestrian from any direction, the front end portion 34 transmits the load to the main body portion 33, and by allowing the main body portion 33 to deform under a constant load, it is possible to generate an appropriate reaction force.

[0093] Furthermore, in the event of a frontal collision, even if the front end portion 34 moves backward due to a rearward load and a crushed residue remains in the lower portion 35L of the protruding surface portion, the lower portion 35L of the protruding surface portion is configured to have lower strength against impact loads from the front of the vehicle compared to the upper portion 35U of the protruding surface portion, so the lower portion 35L of the protruding surface portion can deform rearward, and the crushed residue of the front end portion 34 that is contained within the upper portion 35U of the protruding surface portion 35 of the protruding surface portion 35 that protrudes forward and the lower portion 35L of the protruding surface portion that has deformed rearward moves the entire surface of the beam member 24 almost straight rearward, thereby suppressing the rotational behavior of the beam member 24.

[0094] In short, even if a structure is adopted in which a plate member (lower stiffener 30) is attached to a beam member 24 having closed cross sections 25, 26, it is possible to achieve both pedestrian protection performance and suppression of damage to vehicle parts in the event of a minor collision.

[0095] In addition, in such a vehicle front structure, the protruding surface portion 35 is provided on a part of the vertical surface portion 31 and is formed in a box shape with an upper wall 35a and left and right side walls 35b, and a high-rigidity portion (see vertical rib 45) is arranged in the upper region of the box shape, and a cavity 46 is formed in the lower region (see Figures 6 to 8). According to such a vehicle front structure, a structure in which protruding surface portion lower portion 35L has lower strength against a front impact load than protruding surface portion upper portion 35U can be realized with a simple configuration.

[0096] Furthermore, in such a vehicle front structure, a lower crash can 23 connected to the beam member 24 is provided in front of the subframe 14, and the beam member 24 has a central portion 27 located toward the center of the vehicle width direction and extending along the vehicle width direction, and both end portions 28 that slope toward the rear of the vehicle from the left and right ends of the central portion 27 in the vehicle width direction toward the outside, and the protruding surface portion 35 is provided between the boundary portion β between the central portion 27 and the both end portions 28 and the position of the inner end portion in the vehicle width direction of the lower crash can 23 (see Figure 4). According to such a front structure of the vehicle, when the barrier bar intrudes (see FIG. 9), the protruding surface portion 35 hits the barrier bar before the vertical surface portion 31 hits the barrier bar, so that the collapse behavior can be controlled.

[0097] Furthermore, in this vehicle front structure, the center of the box shape of the protruding surface portion 35 in the vehicle width direction protrudes forward of the vehicle (see central protruding portion 35c) (see FIGS. 4 and 9). According to such a vehicle front structure, the forward protruding portion of the box shape (see central protruding portion 35c) hits the barrier BAR (see FIG. 9) first, and the entire surface of the protruding surface portion 35 can be crushed almost uniformly.

[0098] In addition, in such a vehicle front structure, the front end portion 34 has a front end upper portion 34U located above the main body portion 33 and a front end lower portion 34L located below the main body portion 33, and the front end upper portion 34U is formed further forward of the vehicle and protrudes higher from the main body portion 33 than the front end lower portion 34L (see Figure 6).

[0099] According to this type of front structure of the vehicle, in the event of a frontal collision, the upper end of the front end portion 34 can be made to rotate downward as it moves rearward, which causes the main body portion 33 to bend downward and displace the remaining crushed portion of the front end portion 34 below the vertical surface portion 31.

[0100] In addition, in this vehicle front structure, a rib 41 is provided that connects the front end of the front end portion 34 and the main body portion 33 (see FIG. 6). According to this vehicle front structure, the front end portion 34 can be formed with high rigidity using a simple structure. This high-rigidity front end portion 34 can bear the load when protecting a pedestrian.

[0101] In the configuration of this invention and the correspondence with the above-mentioned embodiment, The plate member of this invention corresponds to the lower stiffener 30 of the embodiment, Similarly, The high rigidity part corresponds to the vertical rib 45, The present invention is not limited to the configurations of the above-described embodiments, and many other embodiments can be obtained.

[0102] For example, in the above embodiment, an engine-driven vehicle having an engine room (motor room) is exemplified as a vehicle, but the present invention can also be applied to an electric vehicle having a motor room (motor room). [Industrial Applicability]

[0103] As described above, the present invention is useful for a front structure of a vehicle that includes a beam member having a closed cross section that is located in front of the subframe and extends in the vehicle width direction, and a plate member that extends from the beam member in the front direction of the vehicle. [Explanation of symbols]

[0104] 14...Subframe 23...Lower crash can 24...Beam member 25,26...Closed section 27...Central part 28...Both ends 30...Lower stiffener (plate member) 31...Vertical section 33...Main body 34…Front end 34U…Upper part of front end 34L…lower part of front end 35...Protruding surface part 35a...Top wall 35b…Side wall 35U... Upper part of the protruding surface part 35L…Lower part of protruding surface 41...Rib 45...Vertical rib (high rigidity section) 46...Cavity β...boundary part

Claims

1. a beam member having a closed cross section that is located in front of the subframe and extends in the vehicle width direction; a plate member extending from the beam member toward the front of the vehicle, The plate member includes a vertical surface portion provided along a front surface portion of the beam member, a main body portion extending from the vertical surface portion toward the front of the vehicle, a front end portion at the front end of the main body portion configured to have higher rigidity against longitudinal loads than the main body portion, and a protruding surface portion spaced away from the vertical surface portion toward the front of the vehicle, the front end portion has a front end upper portion located above the main body portion, the protruding surface portion has a protruding surface portion upper portion located above an upper end of the front end portion upper portion and a protruding surface portion lower portion located below the upper end of the front end portion upper portion, The lower portion of the protruding surface portion is configured to have lower strength against an impact load from the front of the vehicle than the upper portion of the protruding surface portion. Front structure of the vehicle.

2. The protruding surface portion is provided on a part of the vertical surface portion and is formed in a box shape having an upper wall and left and right side walls, A high-rigidity portion is disposed in the upper region of the box shape, and a hollow portion is formed in the lower region. The front structure of a vehicle according to claim 1.

3. A lower crash can connected to the beam member is provided in front of the subframe, The beam member includes a central portion located toward the center in the vehicle width direction and extending along the vehicle width direction; and both end portions inclined so that the outer sides in the vehicle width direction from both left and right ends of the central portion in the vehicle width direction are toward the rear of the vehicle, The protruding surface portion is provided between a boundary portion between the central portion and both end portions and an inner end position in the vehicle width direction of the lower crash can. The front structure of a vehicle according to claim 1 or 2.

4. The center of the box shape of the protruding surface portion in the vehicle width direction protrudes forward of the vehicle.

4. The front structure of a vehicle according to claim 2 or 3.

5. the front end portion has a front end upper portion located above the main body portion and a front end lower portion located below the main body portion, The upper front end portion is formed in a position further forward of the vehicle than the lower front end portion and has a higher protruding height in the vertical direction from the main body portion. The front structure of a vehicle according to any one of claims 1 to 4.

6. A rib is provided to connect the front end of the front end portion and the main body portion. The vehicle front structure according to any one of claims 1 to 5.

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