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 positioned in front of a sub frame 14 in a vehicle and having closed-cross sections 25, 26 extending in a vehicle width direction; and a plate member 30 extending to the vehicle front from the beam member 24. The plate member 30 comprises: a fixation portion 32 fixed to the beam member 24; a body portion 33 extending to the vehicle front from the fixation portion 32; and 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 a longitudinal direction than that of the body portion 33. The front end portion 34 comprises: an upper section 34U located at a higher level than the body portion 33; and a lower section 34L located at a lower level than the body portion 33. The upper section 34U is positioned at the vehicle front relative to the lower section 34L.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 structures have been known as front structures for vehicles. 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 such as that disclosed in Patent Document 1 as the above-mentioned plate member.

[0006] In this case, when the vehicle is hit by a minor collision, the crushed plate member accumulates at the bottom of the beam member, causing the beam member to rotate about the width axis (a virtual axis extending in the vehicle width direction) without deformation, and the lower crash can undergoes bending deformation 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 subframe comprising: a beam member having a closed cross section located at the vehicle front of the subframe and extending in the vehicle width direction; and a plate member extending from the beam member towards the vehicle front, the plate member comprising a fixing portion fixed to the beam member, a main body portion extending from the fixing portion towards the vehicle front, and 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, the front end portion having an upper portion located above the main body portion and a lower portion located below the main body portion, the upper portion being located further forward of the vehicle than the lower portion. A rib is provided connecting the front end of the front end portion and the main body portion, and the beam member has 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 side in the vehicle width direction from both left and right ends of the central portion in the vehicle width direction is toward the rear of the vehicle, and the rib at the front end portion corresponding to the central portion is inclined so that the outer side in the vehicle width direction is toward the rear of the vehicle. The front structure of a vehicle is characterized by the above. With this invention, even if a pedestrian is hit from any direction, the front end transmits the load to the main body and can tolerate deformation of the main body at a constant load, thereby generating an appropriate reaction force.

[0011] In addition, during a frontal collision, the load is input to the upper portion of the front end before the lower portion, so a moment is generated that tends to rotate the upper end of the front end downward toward the rear, causing the main body to bend downward and preventing the main body from being crushed on the front surface 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.

[0012] Furthermore, as described above, since a rib is provided connecting the front end of the front end portion and the main body portion, the front end portion can be formed with high rigidity using a simple structure.

[0013] Furthermore, as mentioned above, the rib at the front end corresponding to the center portion is inclined so that the rear of the vehicle is outward in the width direction, so that the rib does not remain crushed in the event of 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 as described above, the rib is promoted to collapse, and it is possible to prevent the rib from remaining crushed.

[0014] This invention provides a front structure for a vehicle comprising: a beam member having a closed cross-section located at the front of the vehicle of the subframe and extending in the vehicle width direction; and a plate member extending from the beam member towards the front of the vehicle, wherein the plate member comprises a fixing portion fixed to the beam member, a main body portion extending from the fixing portion towards the front of the vehicle, and a front end portion at the front end of the main body portion which is configured to be more rigid against longitudinal loads than the main body portion, wherein the front end portion has an upper portion located above the main body portion and a lower portion located below the main body portion, wherein the upper portion is located further forward of the vehicle than the lower portion, and an undercover mounting portion is provided at the base of the main body portion and extends downward from the base, and a notch is formed in the base of the undercover mounting portion.

[0015] According to this invention, the notch serves as a weakened portion, and the main body can be folded downward from the notch as a starting point, with the base as a fulcrum, thereby shifting the remaining portion on the tip side downward.

[0016] This invention provides a front structure for a vehicle comprising: a beam member having a closed cross-section located in front of the vehicle of the subframe and extending 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 has a fixing portion fixed to the beam member, a main body portion extending in a straight line from the fixing portion in the front direction of the vehicle when viewed from the side of the vehicle, and a front end portion at the front end of the main body portion which is configured to be more rigid against longitudinal loads than the main body portion, wherein the front end portion has an upper portion located above the main body portion and a lower portion located below the main body portion, and the upper portion is located further forward of the vehicle than the lower portion.

[0017] child As an aspect of the invention, the above A lower rib may be provided on the lower surface of the main body portion to connect the fixing portion and the front end portion. According to this invention, the reaction force when protecting a pedestrian can be adjusted by the lower rib. In addition, since the lower rib improves the rigidity of the main body, the main body can be reliably deflected downward in the event of a frontal collision without buckling or bending.

[0018] As an aspect of the present invention, the lower end of the lower rib may be located higher than the lower end of the lower portion. According to this invention, the lower rib does not hinder the rotation of the front end portion during a frontal collision, and the collision reaction force when protecting a pedestrian can be adjusted by the lower rib.

[0019] This invention provides a front structure for a vehicle comprising: a beam member having a closed cross section located in front of the subframe and extending in the vehicle width direction; and a plate member extending from the beam member toward the front of the vehicle, wherein the plate member comprises a fixing portion fixed to a front portion that forms the front surface of the vehicle among the surfaces that constitute the closed cross section of the beam member; a main body portion extending from the fixing portion toward the front of the vehicle; and 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, wherein the front end portion has an upper portion located above the main body portion and a lower portion located below the main body portion, and the upper portion is located forward of the vehicle than the lower portion.

[0020] 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 with high rigidity using a simple structure.

[0021] In one aspect of the present invention, the beam member has a central portion located toward the center of the vehicle width direction and extending along the vehicle width direction, and both end portions inclined so that the outer side in the vehicle width direction from the left and right ends of the central portion is toward the rear of the vehicle, and the rib at the front end portion corresponding to the central portion may be inclined so that the outer side in the vehicle width direction is toward the rear of the vehicle.

[0022] According to this invention, the rib at the front end corresponding to the center portion is inclined so that the rear of the vehicle is outward in the width direction, so that the rib does not remain crushed in the event of 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 as described above, the rib is promoted to collapse, and the remaining crushed portion can be suppressed.

[0023] As an aspect of the present invention, the front end portion may have the lower portion protruding downward from the front end of the main body portion, and the upper portion located at the front end of the lower portion. According to this invention, the boundary between the main body and the lower portion serves as a break point that causes the front end to rotate during a frontal collision. [Effects of the Invention]

[0024] 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]

[0025] [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

[0026] 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 subframe comprising: a beam member having a closed cross section that is located at the vehicle front of the subframe and extends in the vehicle width direction; and a plate member extending from the beam member towards the vehicle front, the plate member comprising a fixing portion fixed to the beam member, a main body portion that extends from the fixing portion towards the vehicle front, and a front end portion at the front end of the main body portion that is configured to have higher rigidity against longitudinal loads than the main body portion, the front end portion having an upper portion located above the main body portion and a lower portion located below the main body portion, the upper portion being located further forward of the vehicle than the lower portion. A rib is provided connecting the front end of the front end portion and the main body portion, and the beam member has 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 side in the vehicle width direction from both left and right ends of the central portion in the vehicle width direction is toward the rear of the vehicle, and the rib at the front end portion corresponding to the central portion is inclined so that the outer side in the vehicle width direction is toward the rear of the vehicle. This was realized by the following configuration. [Example]

[0027] 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.

[0028] 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.

[0029] As shown in FIG. 1, a dash lower panel (dash panel) 1 is provided to separate the engine room and the passenger compartment in the longitudinal direction of the vehicle, and front side frames 3 are provided extending forward from both the left and right sides of a tunnel section 2 formed in this dash lower panel 1 in the width direction of the vehicle.

[0030] 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.

[0031] Upper crash cans 6 extending in the front-to-rear 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 these pair of left and right upper crash cans 6.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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 vehicle relative to the front cross member 15, and left and right side members 17, 17 that connect the front cross member 15 and the 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.

[0040] 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.

[0041] The extension member 19 is formed into a cylindrical shape by combining an upper member and a lower member with a two-part structure, and is configured so that the width of the front part of the extension member 19 in the vehicle width direction is wider than the width of the rear part of the extension member in the vehicle width direction.

[0042] 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.

[0043] 2, lower crash cans 23 extending in the front-to-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.

[0044] 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.

[0045] 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 toward the outside in the vehicle width direction.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 6, the main body 33 extends toward the front of the vehicle substantially perpendicularly from the vertical surface 31 including the fixing portion 32. As shown in the figure, the main body 33 is formed in a linear shape. 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.

[0051] 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). 6, the front end portion 34 has an upper front end portion 34U located above the main body portion 33 and a lower front end portion 34L located below the main body portion 33, and the upper front end portion 34U is located further forward of the vehicle than the lower front end portion 34L. In this embodiment, the upper front end portion 34U is formed by the front piece 39, and the lower front end portion 34L is formed by both the rear inclined piece 37 and the front inclined piece 38.

[0052] 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.

[0053] 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. In short, even when the lower stiffener 30 is used for the beam member 24 having the closed cross sections 25, 26, the configuration is such that both pedestrian protection performance and suppression of damage to vehicle parts in the event of a minor collision are achieved.

[0054] 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 main body 33 and the front end lower portion 34L is configured to be a folding start point that causes the front end 34 to rotate in the event of a frontal collision.

[0055] 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, 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.

[0056] 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.

[0057] 3 and 6(a), a claw portion 40 to be inserted into a hole 24f formed in the front wall 24a of the beam member 24 is integrally formed in the center in the vehicle width direction of the vertical surface portion 31 of the lower stiffener 30. 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.

[0058] 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. 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] Specifically, 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, thereby suppressing the rib 41 from remaining uncrushed.

[0064] 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.

[0065] 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.

[0066] As a result, the reaction force when protecting a pedestrian can be adjusted by the lower ribs 42. More specifically, the reaction force when protecting a pedestrian can be adjusted as desired by changing the number of lower ribs 42 or the thickness of the lower ribs 42. In addition, the lower ribs 42 increase 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.

[0067] 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. 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 portion is provided at the base portion of the main body portion 33 of the lower stiffener 30. 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 FIG. 4, the 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 having 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] 6(b), the protruding surface portion 35 has a protruding surface portion upper portion 35U located above the upper end of the front end upper portion 34U, and a protruding surface portion lower portion 35L located below the upper end of the front end upper portion 34U. In this embodiment, as shown in FIG. 6(b), the protruding surface portion lower portion 35L is set at the same height as the front end upper portion 34U in the vehicle up-down direction.

[0075] 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. Specifically, as shown in Figures 6(b), 7 and 8, a plurality of vertical ribs 45 extending in the vertical direction 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).

[0076] As a result, even if the front end 34 moves backward due to a rearward load and the lower portion 34L of the front end remains crushed, the upper portion 35U of the protruding surface portion 35 that protrudes forward moves the entire surface of the beam member 24 straight backward, thereby suppressing the rotational behavior of the beam member 24.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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, crushing the entire surface of the protruding surface portion 35 almost uniformly.

[0082] 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.

[0083] 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.

[0084] 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. <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. <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. <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. <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.

[0085] 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.

[0086] As described above, the vehicle front structure according to this embodiment comprises: a beam member 24 positioned forward of the subframe 14 and having closed cross sections 25, 26 extending in the vehicle width direction; and a plate member (lower stiffener 30) extending forward of the vehicle from the beam member 24. The plate member (lower stiffener 30) comprises a fixing portion 32 fixed to the beam member 24, a main body portion 33 extending forward of the vehicle from the fixing portion 32, and a front end portion 34 at the front end of the main body portion 33, the front end portion 34 being configured to have higher rigidity against longitudinal loads than the main body portion 33. The front end portion 34 has an upper portion (front end upper portion 34U) positioned above the main body portion 33 and a lower portion (front end lower portion 34L) positioned below the main body portion 33, and the upper portion (front end upper portion 34U) is positioned further forward of the vehicle than the lower portion (front end lower portion 34L) (see FIGS. 1 to 3 and 6).

[0087] 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 can tolerate deformation of the main body portion 33 at a constant load, thereby generating an appropriate reaction force.

[0088] In addition, during a frontal collision, load is input to the upper portion (front end upper portion 34U) of the front end portion 34 before the lower portion (front end lower portion 34L) thereof, and therefore a moment is generated that tends to rotate the upper end of the front end portion 34 downward toward the rear, causing the main body portion 33 to bend downward, thereby preventing the main body portion 33 from being crushed on the front surface of the beam member 24. In short, even if the plate member (lower stiffener 30) is used for the beam member 24 having the 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.

[0089] Furthermore, in such a vehicle front structure, the front end portion 34 has the lower portion (front end lower portion 34L) that protrudes downward from the front end of the main body portion 33, and the upper portion (front end upper portion 34U) that is located at the front end of the lower portion (front end lower portion 34L) (see Figure 6).

[0090] According to such a vehicle front structure, the boundary α between the main body 33 and the lower portion (front end lower portion 34L) becomes a break point that causes the front end 34 to rotate during a frontal collision.

[0091] Furthermore, 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(c)). According to such a vehicle front structure, the front end portion 34 can be formed with high rigidity by the ribs 41 with a simple structure.

[0092] Furthermore, in such a vehicle front structure, 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 incline 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 rib 41 of the front end portion 34 corresponding to the central portion 27 inclines outward in the vehicle width direction toward the rear of the vehicle (see Figures 4 and 5).

[0093] According to this vehicle front structure, the ribs 41 of the front end portions 34 corresponding to the central portion 27 are inclined outward in the vehicle width direction toward the rear of the vehicle, so that the ribs 41 do not remain crushed during a frontal collision. If the ribs were to extend straight in the front-to-rear direction, the ribs would be stretched and would remain crushed, but by inclining the ribs 41 as described above, the collapse of the ribs 41 is promoted, and it is possible to prevent the ribs from remaining crushed.

[0094] Additionally, in this vehicle front structure, the front end portion 34 is configured to be inclined forward (see FIG. 6(c)). According to such a front structure of the vehicle, the front end portion 34 is tilted forward as described above, so that the moment tending to rotate the upper end of the front end portion 34 downward as it moves rearward increases, thereby ensuring that the main body portion 33 bends downward in deformation.

[0095] In addition, the forward tilt structure increases the stroke of the front end portion 34 rotating rearward, suppressing interference of the front end portion 34 with the main body portion 33 and preventing the front end portion 34 from bottoming out. In addition, in such a vehicle front structure, the main body portion 33 is formed in a linear shape, and a lower rib 42 is provided on the underside of the main body portion 33 to connect the fixing portion 32 and the front end portion 34 (see Figure 6(c)).

[0096] According to this vehicle front structure, the reaction force when protecting a pedestrian can be adjusted by the lower rib 42. Furthermore, since the lower rib 42 improves the rigidity of the main body 33, the main body 33 can be reliably deflected downward during a frontal collision without buckling or bending.

[0097] Furthermore, in this vehicle front structure, the lower end of the lower rib 42 is located higher than the lower end of the lower portion (front end lower portion 34L) (see FIG. 6(c)). With this vehicle front structure, the lower rib 42 does not hinder the rotation of the front end portion 34 during a frontal collision. In addition, the lower rib 42 can adjust the collision reaction force when protecting a pedestrian.

[0098] In addition, in such a vehicle front structure, an undercover mounting portion 43 is provided at the base of the main body portion 33, extending downward from the base, and a notch 44 is formed at the base of the undercover mounting portion 43 (see Figures 6(c), 7 and 8).

[0099] According to such a vehicle front structure, the notch 44 serves as a weakened portion, so that the main body 33 can be folded downward from the notch 44 as a starting point, with the base of the main body 33 as a fulcrum, thereby shifting the remaining position on the tip side downward.

[0100] 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 upper portion corresponds to the upper portion 34U of the front end portion. The lower portion corresponds to the lower portion 34L of the front end portion. The present invention is not limited to the configurations of the above-described embodiments.

[0101] 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]

[0102] 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]

[0103] 14...Subframe 24...Beam member 25,26...Closed section 27...Central part 28...Both ends 30...Lower stiffener (plate member) 32…Fixed part 33...Main body 34…Front end 34U…Upper part of front end (upper part) 34L… Lower part of front end (lower part) 41...Rib 42...Lower rib 43...Undercover mounting part 44...Notch

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 fixed portion fixed to the beam member, a main body portion extending from the fixed portion toward the front of the vehicle, and a front end portion configured at a front end of the main body portion to have higher rigidity against a longitudinal load than the main body portion, The front end portion has an upper portion located above the main body portion and a lower portion located below the main body portion, the upper portion is located further forward of the vehicle than the lower portion, a rib connecting the front end of the front end portion and the main body portion; 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 rib at the front end portion corresponding to the central portion is inclined so that the rear portion of the vehicle is on the outside in the vehicle width direction. Front structure of the vehicle.

2. 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 fixed portion fixed to the beam member, a main body portion extending from the fixed portion toward the front of the vehicle, and a front end portion configured at a front end of the main body portion to have higher rigidity against a longitudinal load than the main body portion, The front end portion has an upper portion located above the main body portion and a lower portion located below the main body portion, the upper portion is located further forward of the vehicle than the lower portion, An undercover attachment portion is provided at the base of the main body portion and extends downward from the base, A notch is formed in the base of the undercover mounting portion. Front structure of the vehicle.

3. 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 fixed portion fixed to the beam member, a main body portion extending linearly from the fixed portion toward the front of the vehicle in a side view of the vehicle, and a front end portion configured at a front end of the main body portion to have higher rigidity against a longitudinal load than the main body portion, The front end portion has an upper portion located above the main body portion and a lower portion located below the main body portion, The upper portion is located further forward of the vehicle than the lower portion. Front structure of the vehicle.

4. A lower rib is provided on the underside of the main body portion to connect the fixing portion and the front end portion. The front structure of a vehicle according to claim 3.

5. The lower end of the lower rib is located higher than the lower end of the lower portion. The front structure of a vehicle according to claim 4.

6. 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 fixing portion fixed to a front surface portion that forms a vehicle front surface among surfaces that form the closed cross section of the beam member, a main body portion extending from the fixing portion toward the front of the vehicle, and a front end portion that is configured at a front end of the main body portion to have higher rigidity against a longitudinal load than the main body portion, The front end portion has an upper portion located above the main body portion and a lower portion located below the main body portion, The upper portion is located further forward of the vehicle than the lower portion. Front structure of the vehicle.

7. A rib is provided connecting the front end of the front end portion and the main body portion. The vehicle front structure according to any one of claims 2 to 6.

8. 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 rib at the front end corresponding to the central portion is inclined so that the rear of the vehicle is on the outside in the vehicle width direction. The front structure of a vehicle according to claim 7.

9. The front end portion has the lower portion protruding downward from the front end of the main body portion, and the upper portion located at the front end of the lower portion. The vehicle front structure according to any one of claims 1 to 8.

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