Vehicle body front structure

Abstract

The present invention relates to a vehicle body front structure capable of suppressing deformation of a vehicle body with respect to a full overlap head-on collision and a small overlap head-on collision. The vehicle body front structure includes: a pair of left and right front side frames extending along the front and rear of the vehicle body; a pair of upper side frames disposed on both sides of the power unit chamber and extending along the power unit chamber; a radiator support disposed at the front of the power unit chamber and joined to the front ends of the pair of upper frames; the vehicle body front structure includes: a pair of lower frame extension members extending forward from a front end of the lower frame, the front end portions of the lower frame extension members protruding forward than the radiator support member, and a pair of upper frame extension members extending forward from a front end of the lower frame extension members. And a pair of gussets extending forward from the front end of the lower frame, the front ends of the gussets being disposed further toward the outside in the vehicle width direction than the front ends of the pair of front side frames.

Description

Technical Field

[0001] The present invention relates to a vehicle body front structure including a plurality of frames arranged at a peripheral portion of a radiator support and a lower frame arranged at a lower portion of a front side frame. Background Art

[0002] In recent years, the body structure of automobiles and the like has been required to improve safety in offset collisions in which the vehicle partially collides with an obstacle. In particular, it has been required to improve performance in so-called small overlap frontal collisions in which only the end portions in the vehicle width direction collide with an obstacle in an offset collision.

[0003] As a vehicle body front structure for reducing the deformation of the vehicle body during such a small overlap frontal collision, various technologies have been proposed so far. For example, Patent Document 1 (Japanese Patent Laid-Open No. 2014-104898) discloses a vehicle body front structure in which each front longitudinal beam (front side frame) is combined with a suspension member by a V-shaped support. With such a structure, the vehicle body front structure of Patent Document 1 suppresses the front side frame from tipping inward in the vehicle width direction during a small overlap collision (a small overlap frontal collision). As a result, when a small overlap collision occurs, the vehicle body front structure of Patent Document 1 can cause the vehicle to generate lateral force, thereby reducing the deformation of the vehicle body.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-104898 Summary of the invention

[0007] Technical problem to be solved by the invention

[0008] However, in the case of the structure disclosed in Patent Document 1, for example, depending on the magnitude of the impact during a small overlap frontal collision, the lateral force generated on the vehicle body may not be sufficient. In this case, the collision load is concentrated on the small overlap portion of the front part of the vehicle body (the outer side portion of the front side frame in the vehicle width direction), and the deformation of the vehicle body may not be sufficiently reduced. In addition, in a full overlap frontal collision, depending on the magnitude of the impact, the deformation of the vehicle body may not be sufficiently reduced by the buckling deformation of the V-shaped support member.

[0009] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle body front structure capable of suppressing deformation of the vehicle body in both a full overlap frontal collision and a small overlap frontal collision.

[0010] Technical solutions for solving technical problems

[0011] The vehicle body front structure of one embodiment of the present invention includes: a pair of left and right front side frames extending in the front-rear direction of the vehicle body; a pair of upper side frames arranged on both sides of the power unit chamber in the vehicle width direction and extending along the power unit chamber; a radiator support member arranged in the front part of the power unit chamber and connected to the front end of the pair of upper side frames; and a lower frame arranged at the lower part of the pair of front side frames and supported by the pair of front side frames, the vehicle body front structure having: a pair of lower side frame extension members extending from the front end of the lower frame toward the front of the vehicle body, the front end of which protrudes forward than the radiator support member; and a pair of gussets extending from the front end of the lower frame toward the front of the vehicle body, the front end of which is arranged at a position closer to the outside in the vehicle width direction than the front end of the pair of front side frames.

[0012] Effects of the Invention

[0013] According to the vehicle body front structure of the present invention, deformation of the vehicle body can be suppressed in both a full overlap frontal collision and a small overlap frontal collision. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a perspective view showing the frame structure of the front part of the vehicle body.

[0015] Figure 2 It is an exploded perspective view showing the frame structure of the front part of the vehicle body.

[0016] Figure 3 It is a side view showing the frame structure of the front part of the vehicle body.

[0017] Figure 4 It is a front view showing the frame structure of the front part of the vehicle body.

[0018] Figure 5 It is a side view showing the behavior of the frame of the front part of the vehicle body from the early stage to the middle stage of a full overlap frontal collision.

[0019] Figure 6 It is a side view showing the behavior of the frame of the front part of the vehicle body at the end of a full overlap frontal collision.

[0020] Figure 7 It is a plan view showing the behavior of a frame at the front portion of a vehicle body in the early stage of a small overlap frontal collision.

[0021] Figure 8 It is a plan view showing the behavior of the frame of the front part of the vehicle body in the middle stage of a small overlap frontal collision.

[0022] Fig. 9 It is a plan view showing the behavior of the frame of the front part of the vehicle body at the end of a small overlap frontal collision. DETAILED DESCRIPTION

[0023] Embodiments of the present invention will be described below with reference to the accompanying drawings.

[0024] In addition, in the drawings used in the following description, the scale of each component is different in order to make each component a size that can be recognized on the drawings. Therefore, the present invention is not limited to the number of components shown in these drawings, the shape of components, the size ratio of components, and the relative positional relationship of each component.

[0025] As an example of the vehicle body front structure of the present embodiment, the structure of the vehicle body front of a vehicle equipped with a power unit such as a motor in front of a cab is described. In addition, in the following description, when recorded as "joining", the joining method adopts a joining method represented by welding or mechanical joining.

[0026] like Figure 1 As shown, the vehicle body 1 has a power unit compartment 2 at the front.

[0027] The vehicle body 1 includes a footrest 3 , a pair of front side frames 4 , a pair of upper side frames 5 , a pair of suspension towers 6 , and a radiator support 7 as frames forming the power unit room 2 .

[0028] The footrest 3 extends in the vehicle width direction as a partition wall that divides the cab 8 and the power unit chamber 2. Both ends of the footrest 3 in the vehicle width direction are joined to a pair of left and right front pillars 9 constituting the vehicle body 1. In addition, the upper end of the footrest 3 is joined to a partition 10 extending in the vehicle width direction along the footrest 3.

[0029] A pair of front side frames 4 extend from the lower side of the footrest 3 toward the front of the vehicle body 1 on the outer side of the center portion of the footrest 3 in the vehicle width direction.

[0030] Each of these front side frames 4 is formed by connecting a plurality of frame members.

[0031] Specifically, each front side frame 4 includes, for example, a front side frame body 4a and a crash box 4b. The front side frame body 4a and the crash box 4b have substantially rectangular cross sections.

[0032] The front side frame body 4a is provided with a torque box 11 at the rear end. The rear end of the front side frame 4 is connected to the front end of the side sill 12 and the front end of the rocker 13 by the torque box 11.

[0033] like Figure 2 , Figure 3 As shown, the front end of the front frame body 4a is joined to the radiator support side portion 7c of the radiator support 7 described later. The joining position of the front end of the front frame body 4a and the radiator support side portion 7c is set slightly above the center of the radiator support side portion 7c in the vertical direction.

[0034] like Figure 3 As shown, the crash box 4b is connected to the front end of the front frame body 4a via the radiator support side portion 7c.

[0035] Specifically, the crash box 4b has a mounting flange 15. The mounting flange 15 is formed at the rear end of the crash box 4b.

[0036] Furthermore, the mounting flange 15 is positioned relative to the radiator support side portion 7c opposite to the front end of the front side frame body 4a. In this state, the mounting flange 15 of the crash box 4b is engaged with the radiator support side portion 7c. As a result, the crash box 4b extends toward the front of the vehicle body 1 beyond the radiator support side portion 7c.

[0037] The front end portion of the crash box 4b extending in this way is joined to the bumper beam 16 extending in a curved manner in the vehicle width direction (see Figure 1 ).

[0038] With these structures, in the event of a full overlap frontal collision, each front side frame 4 functions as an energy absorbing member that absorbs the collision load and disperses the collision load to the side sills 12 and the rocker 13 via the torque box 11 .

[0039] A pair of upper side frames 5 are arranged on both sides of the power unit chamber 2 in the vehicle width direction. Each upper side frame 5 extends from the partition plate 10 along the power unit chamber 2 toward the front of the vehicle body. In addition, each upper side frame 5 is bent inward in the vehicle width direction toward the front of the vehicle body from a midway position of each upper side frame 5. In addition, the front end of each upper side frame 5 is joined to both sides of the radiator support upper portion 7a described later.

[0040] That is, each upper frame 5 is curved so as to gradually narrow inward in the vehicle width direction as it moves from the rear end toward the front end.

[0041] A pair of suspension towers 6 are provided between each front side frame 4 and each upper side frame 5. Each suspension tower 6 is formed to protrude inwardly of the power unit chamber 2 in the vehicle width direction. A suspension device (not shown) is installed inside each of the suspension towers 6. The upper part of the suspension device is supported by the suspension towers 6. In addition, a connecting member 28 described later is provided at the front part of each suspension tower 6 configured in this way.

[0042] like Figure 1 , Figure 4 As shown, the radiator support 7 is disposed substantially at the center of the front portion of the power unit chamber 2 of the vehicle body 1. The radiator support 7 is formed in a substantially rectangular frame shape when viewed from the front.

[0043] Specifically, the radiator support 7 includes a pair of upper and lower radiator support upper portions 7a, a radiator support lower portion 7b, and a pair of left and right radiator support side portions 7c.

[0044] The radiator support upper portion 7a and the radiator support lower portion 7b are formed, for example, in a substantially hat-shaped cross section protruding upward and face each other at a predetermined interval in the vehicle body vertical direction.

[0045] like Figure 1 , Figure 2 As shown in FIG. 1 , the radiator support upper portion 7 a extends in the vehicle width direction at the front portion of the vehicle body. As described above, both ends of the radiator support upper portion 7 a in the vehicle width direction are joined to the front ends of the upper side frames 5 .

[0046] The radiator support lower portion 7b extends in the vehicle width direction below the radiator support upper portion 7a. The upper surface of the radiator support lower portion 7b is slightly inclined upward toward the front.

[0047] The pair of radiator support side portions 7c face each other at a predetermined interval in the vehicle width direction. Figure 2 As shown, each radiator support side portion 7c has, for example, a substantially L-shaped cross-section having a wall plate at the front and at the outer side in the vehicle width direction.

[0048] Specifically, the radiator support side portion 7c is configured to include a front wall plate 14a and a side wall plate 14b.

[0049] The front wall plate 14a extends in the up-down direction. As described above, the front end of the front frame body 4a is joined to the back surface of the front wall plate 14a. In addition, the rear end of the crash box 4b is joined to the front surface of the front wall plate 14a.

[0050] The side wall plate 14b is arranged in an L shape from the outer edge of the front wall plate 14a in the vehicle width direction toward the rear. The radiator support side flange 17 (see FIG. 1 ) extending outward in the vehicle width direction is provided at the rear edge of the side wall plate 14b. Figure 2 , Figure 4 ).

[0051] The interval between the radiator support side portions 7c configured in this way inwardly in the vehicle width direction is set to be substantially the same as the interval between the pair of lower frame extension members 25 described later in the vehicle width direction outwardly. The upper and lower ends of the radiator support side portions 7c are joined to both sides of the radiator support upper portion 7a and the radiator support lower portion 7b.

[0052] With these structures, the radiator support 7 functions as a supporting member that supports a radiator (not shown) and a plurality of frame members extending in the front-rear direction of the vehicle body.

[0053] like Figure 2As shown, a lower frame 20 is disposed at the bottom of the power unit chamber 2 configured in this manner. The lower frame 20 is set to be substantially the same height as the radiator support lower portion 7b when viewed from the front, for example. The lower frame 20 includes a plurality of frames.

[0054] Specifically, the lower frame 20 includes a pair of left and right lower frames 21, a pair of front and rear rear beams 22, and a front beam 23. The pair of lower frames 21 and the pair of beams 22, 23 have a substantially rectangular cross-section.

[0055] A pair of lower side frames 21 extend in the front-rear direction of the vehicle body at a predetermined interval in the vehicle width direction. Each lower side frame 21 is disposed at a position on the inner side in the vehicle width direction relative to the front side frame 4. In addition, a suspension arm 24 is mounted on the outer surface in the vehicle width direction of each lower side frame 21. These suspension arms 24 are supported on the lower frame 20 in a manner that allows them to swing freely in the up-down direction.

[0056] A pair of rear cross beams 22 and a pair of front cross beams 23 are provided at a predetermined interval in the rear and front portions of the lower frame 20 , and extend toward the vehicle width direction inner side of each lower side frame 21 .

[0057] A pair of left and right support members 27 a and 27 b protrude from both sides of the rear cross member 22 and the front cross member 23 in the vehicle width direction, respectively.

[0058] like Figure 2 As shown in the figure, a pair of support members 27a together with the rear cross member 22 constitute the rear portion of the lower frame 20. These support members 27a extend outward in the vehicle width direction of the lower frame 21. The length of the support members 27a extending outward in the vehicle width direction is set to a length that is opposite to the bottom surface of the front side frame 4 disposed outside the lower frame 21. That is, each support member 27a is set to a length that enables the upper surface of each support member 27a to abut against the bottom surface of the front side frame 4.

[0059] like Figure 2 As shown, a pair of support members 27b together with the front cross member 23 constitute the front portion of the lower frame 20. These support members 27b extend outward in the vehicle width direction of the lower frame 21. The length of the support members 27b extending outward in the vehicle width direction is set to a length relative to the bottom surface of the front side frame 4 disposed outside the lower frame 21.

[0060] Each of the supporting members 27b has a connecting member 28 at an upper portion of each of the supporting members 27b.

[0061] like Figure 2 , Figure 3 As shown in FIG. 1 , each connecting member 28 extends upward from each supporting member 27 b . These connecting members 28 are disposed at the front portion of the suspension tower 6 .

[0062] Specifically, each connecting member 28 extends upward in a state where the bottom surface of each connecting member 28 is joined to the upper surface of each supporting member 27b. The length of each connecting member 28 extending upward is set to a length that can abut against the bottom surface of the front side frame 4 when each supporting member 27a abuts against the bottom surface of the front side frame 4.

[0063] The lower frame 20 is supported by the front side frames 4 by joining the upper surfaces of the support members 27a and the connecting members 28 to the bottom surfaces of the front side frames 4 in abutting contact. In addition, a power unit (not shown) is supported on the upper surface of the front cross beam 23, for example, via a motor bracket (not shown).

[0064] The lower frame 20 configured in this manner has a pair of left and right lower frame extension members 25 and a pair of left and right gussets 29 at the front portion.

[0065] like Figure 4 As shown, a pair of lower side frame extension members 25 are disposed at positions on the inner side of the front side frame 4 in the vehicle width direction. Figure 3 As shown, each lower frame extension member 25 extends from the front end of the lower frame 20 toward the front of the vehicle body. Also, the front end of each lower frame extension member 25 passes through the frame of the radiator support 7 and protrudes forward from the radiator support 7.

[0066] Specifically, each lower frame extension member 25 extends obliquely upward from the rear end to the front end of the lower frame extension member 25, for example. Figure 3 , Figure 4 As shown in FIG. 1 , the front end portions of the lower frame extension members 25 pass through the upper surface of the radiator support lower portion 7b and the inner side of the radiator support side portion 7c in the vehicle width direction of the radiator support 7. Thus, the front end portions of the lower frame extension members 25 passing through the frame of the radiator support 7 protrude forward from the radiator support 7.

[0067] Each lower frame extension member 25 extending in this way is joined to the frame of the radiator support 7 in a state where the lower surface of the lower frame extension member 25 abuts against the upper surface of the radiator support lower portion 7b. In addition, the lower frame extension member 25 may be joined to the radiator support lower portion 7b by using a bracket.

[0068] Furthermore, the front ends of the lower frame extension members 25 are respectively joined to the lower beams 26 extending and bending in the vehicle width direction (see Figure 1 ).

[0069] With these structures, during a full overlap frontal collision, the lower side frame extension member 25 can utilize the reaction force of the lower frame 20 supported by the front side frame 4 to reinforce the rigidity of the front portion of the vehicle body.

[0070] like Figure 2 As shown, a pair of gussets 29 extend from the front end of the lower frame 20 toward the front of the vehicle body at the front portion of the connecting member 28. The front end of each gusset 29 is disposed outside the front end of the front side frame 4 in the vehicle width direction.

[0071] Specifically, the rear portion of each gusset plate 29 is joined to the front surface of the support member 27b on the vehicle width direction outer side of the lower frame extension member 25. In this way, each gusset plate 29 joined to the front end of the lower frame 20 extends toward the radiator support member side flange 17. Figure 2 , Figure 3 As shown, a mounting flange 30 is formed at the front end of each of the gusset plates 29 , for example.

[0072] Furthermore, the front end of each gusset plate 29 is joined to the radiator support side flange 17 in a state where the mounting flange 30 is in contact with the back surface of the radiator support side flange 17 .

[0073] Thus, the front end of each gusset plate 29 is disposed at a position further outward in the vehicle width direction than the front end of the front side frame 4 and further rearward of the vehicle body than the front ends of the front side frame 4 and the lower side frame extension member 25 (see Figure 3 , Figure 4 ). And, if Figure 4 As shown, the front end of each gusset plate 29 is disposed below the front end of the front side frame 4 and above the front end of the lower side frame extension member 25 in the vertical direction of the vehicle body 1 .

[0074] That is, the front end of each gusset plate 29 is disposed between the front end of the front side frame 4 and the front end of the lower side frame extension member 25 in the vehicle body vertical direction and is disposed outward of the front end of the front side frame 4 in the vehicle width direction.

[0075] With these structures, in a full overlap frontal collision, the gusset 29 can strengthen the rigidity of the front part of the vehicle body by utilizing the reaction force of the lower frame 20 supported on the front side frame 4. In addition, in a small overlap frontal collision, the gusset 29 acts as a starting point for applying lateral force to the vehicle body 1.

[0076] According to such an embodiment, the vehicle body front structure includes: a pair of left and right front side frames 4 extending in the front-rear direction of the vehicle body 1; a pair of upper side frames 5 arranged on both sides of the power unit room 2 in the vehicle width direction and extending along the power unit room 2; a radiator support 7 arranged in the front part of the power unit room 2 and joined to the front ends of the pair of upper side frames 5; and a lower frame 20 arranged in the lower part of the pair of front side frames 4 and supported by the pair of front side frames 4, wherein the vehicle body front structure includes: a pair of lower side frame extension members 25 extending from the front ends of the lower frames 20 toward the front of the vehicle body, and the front ends protruding forward from the radiator support 7; and a pair of gussets 29 extending from the front ends of the lower frames 20 toward the front of the vehicle body, and the front ends are arranged at positions further outward in the vehicle width direction than the front ends of the pair of front side frames 4. With these structures, the vehicle body front structure can suppress deformation of the vehicle body 1 in both full overlap frontal collision and small overlap frontal collision.

[0077] That is, the vehicle front structure includes a lower frame 20 supported by a pair of front side frames 4. Further, the lower frame 20 includes a pair of lower side frame extension members 25 and a pair of gussets 29 at the front end thereof for reinforcing the rigidity of the vehicle front.

[0078] Through such a structure, Figure 5 , Figure 6 As shown, when the vehicle body 1 has a full overlap frontal collision with the fence-like obstacle B, the lower frame extension members 25 and the gussets 29 reinforce the rigidity of the area in front of the lower frame 20 by the reaction force of the lower frame 20 supported on the front side frame 4. Due to the action of the lower frame extension members 25 and the gussets 29, the vehicle body front structure of this embodiment can generate a higher resistance force on the vehicle body 1 than the vehicle body front structure with only the front side frames 4.

[0079] Specifically, the lower side frame extension member 25, which reinforces the rigidity of the front part of the vehicle body together with the front side frame 4, is used from the initial stage to the middle stage of the full overlap frontal collision (see Figure 5 ), and deforms together with the crash box 4b. Thus, the lower frame extension member 25 can absorb the collision load from the initial stage to the middle stage of the full overlap frontal collision together with the crash box 4b.

[0080] Furthermore, at the end of the full overlap frontal collision after the collision box 4b is completely deformed (refer to Figure 6 ), the gussets 29 are deformed together with the front side frames 4 and the lower side frame extension members 25. Thus, each gusset 29 can absorb the collision load of the front part of the vehicle body together with the front side frames 4 and the lower side frame extension members 25.

[0081] In this state, each lower side frame extension member 25 and each gusset plate 29 transmits the collision energy from the front of the vehicle body to the lower frame 20. Then, part of the collision energy transmitted to the lower frame 20 is transmitted to each front side frame 4 supporting the lower frame 20.

[0082] That is, the lower frame 20 can disperse the collision energy transmitted from the lower frame extension members 25 and the gussets 29 to the front frame 4 .

[0083] On the other hand, Figure 7 , Figure 8 , Fig. 9 As shown, for example, when the left end of the vehicle body 1 collides head-on with a rod-shaped obstacle P with a small overlap, the gusset plate 29 reinforces the rigidity of the region outside the front side frame 4 in the vehicle width direction by the reaction force of the lower frame 20. Thus, the gusset plate 29 generates a resistance force for suppressing deformation of the region outside the front side frame 4 in the vehicle width direction.

[0084] Specifically, the front end of the gusset plate 29 is disposed at a position further outward in the vehicle width direction than the front end of the front side frame 4. Figure 7 ), the gusset plate 29 can strengthen the rigidity of the area on the outside of the front side frame 4 in the vehicle width direction.

[0085] In addition, in the mid-range of a small overlap frontal collision (refer to Figure 8 ), the collision load that is not absorbed by the resistance of the gusset plate 29 is converted into a yaw moment that rotates the vehicle body 1 to the right with the contact portion between the rod-shaped obstacle P and the gusset plate 29 as a fulcrum.

[0086] Then, at the end of a small overlap frontal collision (see Fig. 9 ), the rod-shaped obstacle P is guided toward the outer side in the vehicle width direction of the upper frame 5 by the yaw moment rotating to the right, and passes through the upper frame 5. As a result, the vehicle body 1 is freed from the collision load of the rod-shaped obstacle P.

[0087] Thus, the vehicle body front structure of the present embodiment can suppress deformation of the vehicle body 1 in both a full overlap frontal collision and a small overlap frontal collision.

[0088] In addition, each lower frame extension member 25 extends obliquely upward from the rear end to the front end of the lower frame extension member 25. And each of the extended lower frame extension members 25 is respectively engaged with the frame of the radiator support member 7. The midway portion of the lower frame extension member 25 extended in this way is in the full overlap frontal collision (refer to Figure 5 , Figure 6 ) bends downwardly toward the vehicle body 1 due to the collision load.

[0089] Specifically, each lower frame extension member 25 is joined to the frame of the radiator support 7 in a state of being tilted upward toward the front of the vehicle body. Due to the tilt of the lower frame extension members 25, for example, in a full overlap frontal collision, each lower frame extension member 25 can concentrate the collision load on the middle portion of each lower frame extension member 25. In addition, the collision load concentrated on the middle portion of each lower frame extension member 25 can cause the lower frame extension member 25 to deform downwardly from the middle portion of the lower frame extension member 25 as a starting point.

[0090] That is, in a full overlap frontal collision, the vehicle body front structure having the lower frame extension member 25 can more effectively absorb the collision load by deformation of the lower frame extension member 25. In addition, in order to accurately deform the midway portion of the lower frame extension member 25 during a collision, various conditions such as the inclination angle of the lower frame extension member 25, the plate thickness and shape of the lower frame extension member 25 are obtained in advance by experiments or simulations.

[0091] In addition, a connecting member 28 for connecting the lower frame 20 and each front side frame 4 is disposed at the front portion of each suspension tower 6. Each connecting member 28 disposed in this way is restricted from moving toward the rear of the vehicle body by the suspension tower 6. Therefore, each connecting member 28 can further increase the reaction force of the lower frame 20 with respect to the collision load from the front of the lower frame 20. Thus, in a full overlap frontal collision, the vehicle body front structure having the connecting member 28 can generate a higher resistance force for the vehicle body 1.

[0092] In addition, each gusset plate 29 is disposed on the outer side of the lower frame extension member 25 in the vehicle width direction and in front of the connection member 28. Specifically, in each gusset plate 29, the rear portion of each gusset plate 29 is joined to the front surface of the support member 27b. Therefore, each support member 27b is restricted from moving toward the rear of the vehicle body by the suspension tower 6, as is the connection member 28 connected to the upper surface of each support member 27b. As a result, each gusset plate 29 can obtain a high reaction force from the support member 27b in both a full overlap frontal collision and a small overlap frontal collision. That is, in both a full overlap frontal collision and a small overlap frontal collision, the vehicle body front structure having the gusset plate 29 can generate a higher resistance force for the vehicle body 1.

[0093] Furthermore, the front end of each gusset plate 29 is disposed below the front end of the front side frame 4 and above the front end of the lower side frame extension member 25 .

[0094] Specifically, the front end of each gusset plate 29 is disposed between the front end of the front side frame 4 and the front end of the lower side frame extension member 25 in the vertical direction of the vehicle body, and is disposed at a position further outward in the vehicle width direction than the front end of the front side frame 4. That is, the front end of each gusset plate 29 is dispersedly disposed around the radiator support 7 together with the front end of the front side frame 4 and the front end of the lower side frame extension member 25.

[0095] Therefore, in a frontal collision such as a full overlap frontal collision, the gussets 29 arranged in this way can, together with the front side frames 4 and the lower side frame extension members 25, exert sufficient resistance to a wide area of ​​the front portion of the vehicle body.

[0096] Furthermore, the vehicle body front structure in the present embodiment may also be applied to, for example, an offset frontal collision that is between a full overlap frontal collision and a small overlap frontal collision.

[0097] The invention described in the above embodiment is not limited to the above mode, and various modifications can be implemented in the implementation stage without departing from the scope of the present invention. In addition, the above mode includes inventions at various stages, and various inventions can be extracted by appropriate combinations of the disclosed multiple constituent elements.

[0098] Furthermore, even if some of the constituent elements are deleted from all the constituent elements shown in the above-described embodiment, as long as the described problem can be solved and the described effect can be obtained, the structure after deleting these constituent elements can be extracted as an invention.

[0099] Explanation of symbols

[0100] 1……Body

[0101] 2...Power unit room

[0102] 3...Footrest

[0103] 4...Front side frame

[0104] 4a...Front frame body

[0105] 4b... Collision Box

[0106] 5...Upper side frame

[0107] 6...Suspension tower

[0108] 7...Radiator support

[0109] 7a... Upper part of radiator support

[0110] 7b... Radiator support lower part

[0111] 7c...Radiator support side

[0112] 8... Cab

[0113] 9...Front pillar

[0114] 10... Partition

[0115] 11...Torque box

[0116] 12……Side beam

[0117] 13...Bottom beam

[0118] 14a…Front wall panel

[0119] 14b...Side wall

[0120] 15……Flange

[0121] 16……Bumper beam

[0122] 17...Radiator support side flange

[0123] 20... Lower frame

[0124] 21... Lower side frame

[0125] 22...Rear beam

[0126] 23...Front beam

[0127] 24...Suspension arm

[0128] 25... Lower side frame extension

[0129] 26... Lower beam

[0130] 27a...Supporting parts

[0131] 27b...Supporting parts

[0132] 28...Connecting parts

[0133] 29...Gusset

[0134] 30……Flange

[0135] B……Fence-like obstacles

[0136] P…Pole-shaped obstacle.

Claims

1. A vehicle body front structure, characterized in that: include: a pair of left and right front side frames extending in the front-rear direction of the vehicle body; a pair of upper side frames, which are arranged on both sides of the power unit room in the vehicle width direction and extend along the power unit room; a radiator support member disposed at the front portion of the power unit chamber and engaged with the front ends of the pair of upper frames; and a lower frame, which is arranged at the lower part of the pair of front side frames and is supported by the pair of front side frames, Wherein, the front structure of the vehicle body comprises: a pair of lower frame extension members extending from the front end of the lower frame toward the front of the vehicle body, with front end portions protruding forward of the radiator support; and A pair of gussets extend from the front end of the lower frame toward the front of the vehicle body, and the front ends are arranged at the outer sides in the vehicle width direction than the front ends of the pair of front side frames.

2. The vehicle body front structure according to claim 1, characterized in that: The lower frame extension member is disposed on the inner side of the front frame in the vehicle width direction, and the front end of the lower frame extension member passes through the frame of the radiator support so as to be inclined upward toward the front.

3. The vehicle body front structure according to claim 1 or claim 2, characterized in that: have: a suspension tower supporting a suspension device between the front side frame and the upper side frame; as well as A connecting member connects the lower frame and the front side frame at the front portion of the suspension tower.

4. The vehicle body front structure according to claim 3, characterized in that: The rear portion of the gusset is disposed on the outer side in the vehicle width direction of the lower frame extension member and in front of the connecting member.

5. The vehicle body front structure according to claim 2, characterized in that: The front end of the gusset is disposed below the front end of the front side frame and above the front end of the lower side frame extension member in the up-down direction of the vehicle body.

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