Front body structure

Abstract

To provide a vehicle body front structure which rigidly receives a load input to a front side frame by a rear part of the front side frame, and can obtain smooth collapse of the front side frame, when an impact load from the front is input.SOLUTION: A vehicle body front structure includes a floor member, a front side frame 10, a dash board lower panel, and a load transmission block 11 which is an integral cast component. The load transmission block 11 has a frame fixing part 17, a floor fixing part 18, and a connection wall 19. The front part of the floor member is fixed to the frame fixing part 17. The front part of the floor member is fixed to the floor fixing part 18. The connection wall 19 extends generally along the dash board lower panel, and connects the frame fixing part 17 and the floor fixing part 18. On the upper face side of the connection wall 19, a plurality of upper side reinforcement ribs 20 which are erected upward and extend in a longitudinal direction are provided so as to be separated from each other in a vehicle width direction.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vehicle front body structure. [Background technology]

[0002] In recent years, various efforts to provide access to sustainable transportation systems have been gaining momentum. To achieve this, we are focusing on further improving transportation safety and convenience through research into improving vehicle body rigidity.

[0003] BACKGROUND ART A known vehicle body front structure has a pair of front side frames disposed on the left and right sides of the front of the vehicle, with rear portions of the front side frames connected to a load support member (see, for example, Patent Document 1).

[0004] The vehicle front body structure described in Patent Document 1 is designed to collapse the front side frames in multiple stages depending on the magnitude of an impact load input from the front. The rear portions of the left and right front side frames of this vehicle front body structure are connected to load support members positioned below the front side frames. In this vehicle front body structure, when an impact load is input from the front of the vehicle, the input load is reliably received by the load support members at the rear of the front side frames, thereby ensuring that the front side frames are reliably collapsed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-82932 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the vehicle front body structure described in Patent Document 1, the load support members that receive the load when a front impact load is applied are positioned offset downward from the front side frames. As a result, when an impact load is applied, a large moment is likely to occur around the connection between the rear of the front side frame and the load support members. The generation of this moment may hinder the smooth collapse of the front side frames. Improvements in this regard are desired.

[0007] Therefore, the present invention aims to provide a vehicle front body structure that can rigidly receive the load input to the front side frames at the rear portions of the front side frames when an impact load is input from the front, thereby ensuring smooth crushing of the front side frames.The present invention will also contribute to the development of sustainable transport systems. [Means for solving the problem]

[0008] In order to solve the above problems, the vehicle body front structure according to the present invention employs the following configuration. A vehicle body front structure according to one aspect of the present invention includes a floor member (e.g., floor member 12 in the embodiment) disposed below a vehicle interior (e.g., vehicle interior 2 in the embodiment), a front side frame (e.g., front side frame 10 in the embodiment) extending forward from a position higher than the floor member at the front of the vehicle interior, a dashboard lower panel (e.g., dashboard lower panel 13 in the embodiment) standing forward and upward from a front portion of the floor member to cover the front of the vehicle interior, and a load transfer block (e.g., load transfer block 14 in the embodiment) that is an integrally cast part connecting a rear portion of the front side frame and a front portion of the floor member. The load transmission block has a frame fixing portion (for example, frame fixing portion 17 in the embodiment) to which a rear portion of the front side frame is fixed, a floor fixing portion (for example, floor fixing portion 18 in the embodiment) to which a front portion of the floor member is fixed, and a connecting wall (for example, connecting wall 19 in the embodiment) that extends substantially along the dashboard lower panel and connects the frame fixing portion and the floor fixing portion, and is characterized in that a plurality of upper reinforcing ribs (for example, upper reinforcing rib 20 in the embodiment) that stand upward and extend in the fore-and-aft direction are provided at intervals in the vehicle width direction on the upper surface side of the connecting wall.

[0009] In the vehicle front body structure configured as described above, when an impact load is applied from the front of the front side frame, the load is transmitted to the floor member via the load transmission block. The load, input from the front side frame to the frame fixing portion of the load transmission block, is then transmitted to the floor fixing portion through the connecting wall, which slopes downward and rearward. A compressive load acts on the upper surface of the connecting wall, but this compressive load is absorbed by the multiple upper reinforcing ribs provided on the upper surface of the connecting wall. The multiple upper reinforcing ribs rise upward, extend in the fore-and-aft direction, and are spaced apart in the vehicle width direction. This allows the compressive load acting on the upper surface of the connecting wall to be efficiently absorbed. As a result, when an impact load is input from the front, the rear side of the front side frame is rigidly supported by the load support block, and the extended area on the front side is smoothly crushed.

[0010] The connecting wall may be provided with a panel fixing portion (for example, the panel fixing portion 23 in the embodiment) that is fixed to the dashboard lower panel above the upper reinforcing rib.

[0011] In this case, the panel fixing portion of the connecting wall is fixed to the dashboard lower panel above the upper reinforcing rib of the connecting wall. Therefore, when an impact load is applied, part of the load is absorbed by the dashboard lower panel. As a result, the impact load transmitted to the connecting wall of the load transfer block is distributed between the path that passes through the panel fixing portion and the path that passes through the floor fixing portion and is transmitted to the load support member at the front of the vehicle compartment. Therefore, when this configuration is adopted, it is possible to avoid load concentration at the fixing point of the floor fixing portion.

[0012] An upper extension rib (e.g., upper extension rib 26 in the embodiment) that is continuous with the upper reinforcing rib is provided on the upper surface of the floor fixing portion, and a lower rib (e.g., lower rib 27 in the embodiment) in which rib elements (e.g., rib element 27a in the embodiment) that protrude downward extend in multiple directions is provided on the lower surface of the floor fixing portion, and the protruding height of the upper extension rib may be set higher than the protruding height of the lower rib.

[0013] In this case, when a frontal impact load is input, the upper extension rib of the floor fixing part can reliably absorb the compressive load acting on the joint between the connecting wall and the floor fixing part. Furthermore, in this configuration, the protruding height of the upper extension rib, on which the compressive load acts, is set higher than the protruding height of the lower rib, on which the tensile load acts. Therefore, when this configuration is adopted, deformation and deflection of the connecting wall and the floor fixing part can be efficiently restricted, and the effective thickness of the lower rib, which has multiple rib elements extending in multiple directions, can be reduced.

[0014] It is desirable that the lower rib, which is disposed in a region adjacent to the end of the floor fixing portion in the vehicle width direction, is set so that the extension direction of the rib element does not face the vehicle width direction.

[0015] In this case, in the region where the rib element does not face the vehicle width direction, when an impact load is input from the vehicle width direction, that portion is more likely to deform in the vehicle width direction. Therefore, when an impact load is input from the side of the vehicle, the outer region of the floor fixing part in the vehicle width direction can be smoothly deformed, allowing the input impact to be absorbed efficiently. [Effects of the Invention]

[0016] The vehicle front body structure according to the present invention includes a plurality of upper reinforcing ribs that rise upward and extend in the fore-and-aft direction and are spaced apart in the vehicle width direction on the upper surfaces of the connecting walls of the load transfer blocks. Therefore, when an impact load is applied from the front side of the front side frames, the compressive load acting on the upper surfaces of the connecting walls of the load transfer blocks can be efficiently absorbed by the plurality of upper reinforcing ribs. Therefore, when the vehicle front body structure according to the present invention is adopted, the load applied to the front side frames when an impact load is applied from the front is rigidly absorbed by the rear portions of the front side frames, resulting in smooth collapse of the front side frames. Therefore, the energy of the applied impact load can be efficiently absorbed by the smooth collapse of the front side frames. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 2 is a perspective view of the front of the vehicle according to the embodiment. [Figure 2] FIG. 2 is a side view of the front part of the vehicle according to the embodiment. [Figure 3] FIG. 2 is a perspective view of the load transmission block according to the embodiment, seen from above the rear side. [Figure 4] 4 is a cross-sectional view of the front of the vehicle corresponding to the cross section IV-IV in FIG. 3 . [Figure 5] FIG. 4 is a bottom view of the load transmission block according to the embodiment. [Figure 6] FIG. 2 is a perspective view of the load transmission block according to the embodiment, seen from below. [Figure 7] 5 is a cross-sectional view of the load transmission block taken at a position slightly shifted in the vehicle width direction from the cross-section of FIG. 4. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, an arrow FR pointing forward of the vehicle, an arrow UP pointing upward of the vehicle, and an arrow LH pointing to the left side of the vehicle (left side as viewed from the front) are shown at appropriate locations.

[0019] FIG. 1 is a perspective view of the front part of a vehicle 1 according to this embodiment, and FIG. 2 is a side view of the front part of the vehicle 1 as seen from the left side. 1 and 2, reference numeral 2 denotes a passenger compartment where passengers ride, and reference numeral 3 denotes a front compartment located in front of the passenger compartment 2 and accommodating a drive motor, engine, etc. Front side frames 10 extending substantially along the longitudinal direction of the vehicle body are disposed on both sides of the front compartment 3 in the vehicle width direction. The rear ends of the left and right front side frames 10 are connected to a frame member at the front of the passenger compartment 2 via load transmission blocks 11, which will be described in detail later.

[0020] Side sills 4 extending substantially along the longitudinal direction of the vehicle body are disposed on the left and right sides of the lower portion of the passenger compartment 2. A floor panel 5 disposed below the passenger compartment 2 is mounted on the left and right side sills 4. The floor panel 5 is reinforced by a plurality of reinforcing frames (not shown) extending in the longitudinal and transverse directions of the vehicle body. In this embodiment, the floor panel 5 and these reinforcing frames are collectively referred to as a floor member 12. The left and right front side frames 10 extend forward from a position above the floor member 12.

[0021] The front of the passenger compartment 2 is separated from the front compartment 3 by a dashboard lower panel 13. The lower end of the dashboard lower panel 13 is connected to the front edge of the floor member 12, and stands upright at an angle forward and upward from the front of the floor member 12. The upper part of the dashboard lower panel 13 is connected to a cowl top panel 14 and other frame members.

[0022] Front pillars 6, which form the leading edges of the front door openings, are connected to the front ends of the left and right side sills 4. Upper members 7, which extend substantially along the longitudinal direction of the vehicle body, are connected to the front side of the upper portion of each front pillar 6 at a position outside the front compartment 3 in the vehicle width direction. The upper members 7 curve downward from the left and right front pillars 6 toward the front of the vehicle body, and their front ends extend to positions outside the front ends of the front side frames 10. The front ends of each upper member 7 are connected to the front ends of the corresponding left and right front side frames 10 via connecting members (not shown). Damper housing portions 15 at the left and right upper portions of the load transmission block 11, which will be described in detail later, are connected to the base portions (rear regions) of the left and right upper members 7. The damper housing portions 15 support the upper portions of the dampers of the front suspensions (not shown).

[0023] Fig. 3 is a perspective view of the load transmission block 11 as seen from above the rear, and Fig. 4 is a cross-sectional view of the front part of the vehicle corresponding to the cross section IV-IV in Fig. 3. Each of the left and right front side frames 10 fixed to the load transmission block 11 is formed in a rectangular (quadratic) frame shape as shown in Figures 1 and 4. The rear end of the front side frame 10 is inserted into a frame fixing portion 17 of the load transmission block 11, which will be described later, and in this state is fixed to the frame fixing portion 17 with a plurality of bolts 35A, 35B (fastening members). The front side frame 10 is formed from, for example, aluminum or an iron-based metal.

[0024] The front side frame 10 is a framework member that supports drivetrain components and suspension members arranged in the front compartment 3, and absorbs the energy of an impact load by collapsing in the front-to-rear direction when an impact load is applied from the front of the vehicle. As shown in FIG. 2, a plurality of beads 21 extending in the up-down direction are provided on the left and right side walls of the front side frame 10. The plurality of beads 21 are arranged on the side walls of the front side frame 10 at intervals in the front-to-rear direction. The plurality of beads 21 encourage the front side frame 10 to undergo bellows-like collapsing deformation when an impact load is applied. The beads 21 extending in the vertical direction are provided only in the front-to-rear direction middle to front regions of the side walls of the front side frame 10. A plurality of beads 22 extending in the front-to-rear direction are provided in the rear regions of the side walls of the front side frame 10. These beads 22 extending in the front-to-rear direction restrict deformation of the rear region of the front side frame 10 at the initial stage of collapse when an impact load is input.

[0025] Fig. 5 is a bottom view of the left half region of the load transmission block 11. Fig. 6 is a perspective view of the left half region of the load transmission block 11 as seen from below and front. Fig. 7 is a cross-sectional view of the load transmission block 11 taken at a position slightly shifted in the vehicle width direction from the cross-section of Fig. 4. As shown in Fig. 3, the load transmission block 11 is formed in a bilaterally symmetrical shape. The load transmission block 11 has a damper housing portion 15, a frame fixing portion 17, a connecting wall 19, and a floor fixing portion 18 in each of its left and right regions. The load transmission block 11, which has these elements, is integrally cast from, for example, aluminum. In other words, the load transmission block 11 is an integrally cast part having the above-mentioned components.

[0026] As described above, the damper housing 15 is a portion that supports the upper portion of the damper of the front suspension, and as shown in Fig. 1, is disposed above the front side frame 10 and further outward in the vehicle width direction than the front side frame 10. The damper housing 15 is formed in a downward-facing bowl shape (a downward-facing cylindrical shape with a closed bottom), and the damper is disposed below (inside) the bowl-shaped portion. The top of the damper housing 15 supports the upper portion of the damper of the front suspension.

[0027] As described above, the damper housing portions 15 are connected to the base portions of the corresponding left and right upper members 7 by bolting or the like. In addition, the cowl top panel 14 is mounted on the left and right damper housing portions 15 connected to the upper members 7. The left and right ends of the cowl top panel 14 are connected to the corresponding left and right damper housing portions 15 by bolting or the like.

[0028] The frame fixing portion 17 is connected to a lower side wall 15s on the inner side in the vehicle width direction of the damper housing portion 15. The frame fixing portion 17 is a portion that fixes the rear portion of the front side frame 10 and is formed in a substantially rectangular block shape extending in the front-to-rear direction of the vehicle body. As shown in FIG. 4 , the block portion of the frame fixing portion 17 is provided with a recess 30 that is rectangular in front view and into which the rear portion of the front side frame 10 is inserted. The recess 30 opens toward the front of the vehicle, and a load-receiving rib 31 protrudes from the bottom on the side opposite the opening. The rib 31 is a load-supporting wall that protrudes toward the front of the vehicle from the bottom wall 30a of the recess 30, and two rib pieces intersect to form an X shape in front view. The front end surface of the rib 31 is formed flat over its entire area. When the front side frame 10 is inserted into the recess 30, the front end surface of the rib 31 faces the rear end surface of the front side frame 10 with a small gap between them. If the rear of the front side frame 10 attempts to move backward when an impact load is input from the front, the rear end face of the front side frame 10 abuts against the front face of the rib 31. This prevents the front side frame 10 from moving backward too much.

[0029] Furthermore, a load support wall 32 that is continuous with the upper opening edge of the recess 30 is provided on the front side of the block portion of the frame fixing portion 17. The load support wall 32 is a flat wall that is perpendicular to the fore-and-aft direction of the vehicle body and stands vertically upward from the upper opening edge of the recess 30.

[0030] A bracket 33, which is generally L-shaped in side view, is fixed by welding or the like to the upper surface of the front side frame 10 near the rear. An upright piece 33a of the bracket 33 abuts against the front surface of the load support wall 32 of the frame fixing portion 17 and is fixed to the load support wall 32 in this state by a bolt 34 (fastening member). The shaft of the bolt 34 extends along the fore-and-aft direction of the vehicle body, and by tightening the bolt 34 into the load support wall 32, it restricts displacement of the front side frame 10 in the fore-and-aft direction of the vehicle body.

[0031] Furthermore, the rear portion of the front side frame 10 inserted into the recess 30 of the frame fixing portion 17 is fastened to the bottom wall and one side wall of the recess 30 by a plurality of bolts 35A, 35B (fastening members). The bolt 35A penetrates the bottom wall of the recess 30 and is fastened to a cylindrical nut 36 made of an iron-based metal protruding from the upper surface of the bottom wall. Similarly, the bolt 35B penetrates the side wall of the recess 30 and is fastened to a cylindrical nut 36 made of an iron-based metal protruding from the inner surface of the side wall.

[0032] A reinforcing wall 37 (bulkhead) is provided inside the rear region of the front side frame 10, extending horizontally and connecting the left and right side walls of the front side frame 10. The reinforcing wall 37 extends from the rear end of the front side frame 10 to a position forward of the connection between the front side frame 10 and the frame fixing part 17 by the bracket 33 and the bolt 34. The reinforcing wall 37 extends in the front-to-rear direction across the connection between the front side frame 10 and the frame fixing part 17 by the bolts 35A, 35B and the connection between the bracket 33 and the bolt 34.

[0033] The floor fixing portion 18 of the load transfer block 11 extends in the vehicle width direction along the front edge of the floor member 12. The floor fixing portion 18 is formed in the shape of a long plate with sufficient thickness both above and below. A bulge portion 18e that bulges outward in a trapezoidal shape toward the rear of the vehicle body is provided on the outer side of the floor fixing portion 18 in the vehicle width direction. A plurality of fastening holes 38 that penetrate in the vertical direction are formed over almost the entire area of ​​the floor fixing portion 18, including the bulge portion 18e. The fastening holes 38 penetrate in the vertical direction. Each fastening hole 38 can receive the shank of a bolt 39 (see Figure 2) that fastens and secures the floor fixing portion 18 to the floor member 12. The left and right symmetrical regions of the load transmission block 11 are connected to each other by a floor fixing portion 18 in the left region and a floor fixing portion 18 in the right region. Specifically, as shown in Fig. 3, the floor fixing portion 18 in the left region and the floor fixing portion 18 in the right region are connected to each other by a connecting block portion 40 at approximately the center in the vehicle width direction.

[0034] The connecting wall 19 of the load transfer block 11 extends substantially along the front surface of the dashboard lower panel 13 disposed at the front of the passenger compartment 2, and connects the frame fixing part 17 to the floor fixing part 18 below it. The connecting wall 19 is formed in a plate shape with sufficient thickness, similar to the above-mentioned floor fixing part 18. The connecting wall 19 smoothly continues to the floor fixing part 18 below so as to form a continuous plate shape.

[0035] The upper end of the connecting wall 19 is connected to the rear lower end of the block portion of the frame fixing portion 17. The width of the connecting wall 19 in the vehicle width direction widens downward from the connection portion with the frame fixing portion 17 as an apex. In other words, the connecting wall 19 is formed so as to form a substantially isosceles triangle when viewed from the front. The lower end region of the connecting wall 19, where the width widens downward, is continuous with (connected to) the floor fixing portion 18.

[0036] A plurality of upper reinforcing ribs 20 that stand upward and extend in the front-rear direction (diagonally front-rear direction) are provided on the upper surface of the connecting wall 19. The plurality of upper reinforcing ribs 20 are formed on the upper surface of the connecting wall 19 so as to be spaced apart in the vehicle width direction and to be parallel to each other.

[0037] As shown in FIGS. 3 and 4, the upper surface of the upper region of the connecting wall 19 where the width in the vehicle width direction is narrowed is formed with a panel fixing portion 23 which is recessed in a stepped shape and has a flat upper surface. In contrast, the dashboard lower panel 13, which is disposed opposite the upper rear side of the load transmission block 11, has a curved wall 24 with a generally L-shaped cross section provided at a position facing the panel fixing portion 23 on the connecting wall side. This curved wall 24 may be formed integrally with the dashboard lower panel 13, or may be formed as a separate component and connected to the dashboard lower panel 13. One surface of the curved wall 24 is placed over the upper surface of the panel fixing portion 23 formed on the connecting wall of the load transmission block 11. In this state, the panel fixing portion 23 is fastened to the curved wall 24 (dashboard lower panel 13) by bolts 25 (fastening members).

[0038] Here, as described above, the panel fixing portion 23 is formed on the upper surface of the upper region of the connecting wall 19 where the width in the vehicle width direction is narrowed, and the upper reinforcing rib 20 extending in the front-rear direction is disposed immediately below the panel fixing portion 23 on the upper surface of the connecting wall 19. In other words, the panel fixing portion 23 is located in a front-upper position of some of the upper reinforcing ribs 20.

[0039] 3, 4, and 7, upper extension ribs 26 that are continuous with the upper reinforcement ribs 20 on the connecting wall 19 are provided on the upper surface of the floor fixing portion 18. Each upper extension rib 26 extends in the front-to-rear direction so as to be continuous with the corresponding upper reinforcement rib 20.

[0040] 5 to 7, a lower rib 27 that protrudes downward is provided on the underside of the floor fixing part 18. The lower rib 27 has multiple rib elements 27a that protrude downward and extend in multiple directions, and the rib elements 27a are connected to each other. Some of the rib elements 27a are connected to the peripheral wall part 18a that forms the outer contour of the floor fixing part 18. The rib elements 27a of the lower rib 27 are connected to other rib elements 27a and the peripheral wall part 18a, thereby forming a high-strength structural part, including a truss structure or a tubular structure, on the underside of the floor fixing part 18. The lower rib 27 is also formed continuously on the lower surface of the connecting wall 19 .

[0041] Also, as shown in Figure 7, the protruding height H1 of the upper extension rib 26 provided on the upper surface side of the floor fixing part 18 is set to be higher than the height of the lower rib 27 provided on the lower surface side of the floor fixing part 18.

[0042] As shown in FIG. 5, the lower rib 27 disposed in the area close to the side end of the floor fixing part 18 is set so that the rib element 27a does not face in the vehicle width direction.

[0043] <Effects of the embodiment> As described above, the vehicle front body structure of this embodiment includes the load transmission block 11, which is an integrally cast part having the frame fixing portion 17, the floor fixing portion 18, and the connecting wall 19. The connecting wall 19 extends substantially along the dashboard lower panel 13 and connects the frame fixing portion 17 and the floor fixing portion 18. A plurality of upper reinforcement ribs 20, which stand upward and extend in the front-rear direction, are provided on the upper surface of the connecting wall 19 at intervals in the vehicle width direction. Therefore, when an impact load is applied from the front side of the front side frame 10, the compressive load acting on the upper surface of the connecting wall 19 of the load transmission block 11 can be efficiently absorbed by the plurality of upper reinforcement ribs 20. Therefore, the load transmission block 11 and the floor member 12 can suppress movement of the front side frame 10 due to a moment acting on the front side frame 10 due to the input of the impact load. As a result, the rear side of the front side frame 10 is rigidly supported by the load transmission block 11, allowing the forward extension region of the front side frame 10 to be smoothly crushed. Therefore, when the vehicle front body structure of this embodiment is adopted, the energy of the input impact load can be efficiently absorbed by the front side frames 10 smoothly collapsing.

[0044] In particular, in the vehicle body front structure of this embodiment, the damper housing portion 15 is integrally formed on the upper part of the frame fixing portion 17 of the load transmission block 11, and the damper housing portion 15 is connected to the upper member 7, which is a framework member of the side of the vehicle body. Therefore, when an impact load is input from the front of the vehicle, the displacement of the rear portion of the front side frame 10 can be more rigidly suppressed. Therefore, when this configuration is adopted, the extended region of the front side frame 10 can be more smoothly crushed when an impact load is input from the front of the vehicle. Furthermore, in this embodiment, since the damper housing portion 15 is formed integrally with the load transmission block 11, the number of components of the vehicle can be reduced compared to when the damper housing is provided as a separate part, thereby reducing product costs and facilitating assembly.

[0045] Furthermore, in the vehicle body front structure of this embodiment, the connecting wall 19 of the load transmission block 11 is provided with a panel fixing portion 23 that is fixed to the dashboard lower panel 13 above the upper reinforcing rib 20. Therefore, when an impact load is input from the front, part of the load is received by the dashboard lower panel 13 at a position above the upper reinforcing rib 20. As a result, the impact load transmitted to the connecting wall 19 of the load transmission block 11 is distributed between a path that passes through the panel fixing portion 23 and a path that passes through the floor fixing portion 18, and is transmitted to the load support member at the front of the vehicle compartment. Therefore, when this configuration is adopted, it is possible to avoid the load concentrating at the fixing point of the floor fixing portion 18.

[0046] Furthermore, in the vehicle body front structure of this embodiment, an upper extension rib 26 that continues from the upper reinforcing rib 20 is provided on the upper surface of the floor fixing portion 18 of the load transfer block 11, and a lower rib 27 is provided on the underside of the floor fixing portion 18. The lower rib 27 has a structure in which rib elements 27a that protrude downward extend in multiple directions. Therefore, when an impact load is input from the front, the upper extension rib 26 of the floor fixing portion 18 can reliably withstand the compressive load acting on the joint between the connecting wall 19 and the floor fixing portion 18. Furthermore, the lower rib 27 can increase the rigidity of the floor fixing portion 18 in various directions. Furthermore, in this embodiment, the protruding height of the upper extension rib 26 is set to be higher than the protruding height of the lower rib 27. As a result, the upper extension rib 26 can efficiently restrict deformation and bending of the connecting wall 19 and the floor fixing portion 18 when a frontal impact load is input, and moreover, the effective thickness of the lower rib 27, from which multiple rib elements 27a extend in multiple directions, can be made thin. Therefore, the rigidity of the joint between the connecting wall 19 and the floor fixing portion 18 can be maintained high while keeping the effective thickness of the floor fixing portion 18 thin.

[0047] Furthermore, in the vehicle body front structure of this embodiment, the lower rib 27, which is disposed in an area of ​​the floor fixing part 18 close to the end in the vehicle width direction, is set so that the extension direction of the rib element 27a does not face the vehicle width direction. Therefore, when an impact load is input from the side of the vehicle 1, the outer area in the vehicle width direction of the floor fixing part 18 is smoothly deformed, and the input impact can be efficiently absorbed.

[0048] The present invention is not limited to the above-described embodiment, and various design modifications are possible without departing from the spirit of the present invention. For example, in the above-described embodiment, only one panel fixing portion 23 is provided on the upper portion of each connecting wall 19 of the load transmission block 11, but multiple panel fixing portions 23 may be provided on each connecting wall 19.

[0049] Furthermore, in the above embodiment, the damper housing portion 15 is formed integrally with the load transmission block 11, but the damper housing portion 15 does not necessarily have to be provided integrally with the load transmission block 11.

[0050] In the above embodiment, the load transmission block 11 is integrally formed with a left region block to which the left front side frame 10 is fixed and a right region block to which the right front side frame 10 is fixed. However, the load transmission block may be configured such that the left region block and the right region block are separate parts.

[0051] Furthermore, in the above embodiment, the floor fixing portion 18 of the load transfer block 11 is provided with the upper extension rib 26 and the lower rib 27, but the upper extension rib 26 and the lower rib 27 are not necessarily provided. Also, a rib having multiple rib elements extending in multiple directions may be provided on both the upper and lower surfaces of the floor fixing portion 18. [Explanation of symbols]

[0052] 2…Vehicle compartment 10...Front side frame 11...Load transfer block 12...Floor material 13...Dashboard lower panel 17...Frame fixing part 18...Floor fixing part 19...Connecting wall 20...Upper reinforcing rib 23...Panel fixing part 26...Upper extension rib 27...Lower rib 27a...Rib element

Claims

1. a floor member disposed below the vehicle interior; a front side frame extending forward from a position higher than the floor member at the front of the vehicle interior; a dashboard lower panel that stands upward and forward from a front portion of the floor member and covers the front of the vehicle interior; a load transfer block that is an integrally cast part that connects the rear portion of the front side frame and the front portion of the floor member, The load transmission block is a frame fixing portion to which a rear portion of the front side frame is fixed; a floor fixing portion to which the front portion of the floor member is fixed; a connecting wall that extends substantially along the dashboard lower panel and connects the frame fixing portion and the floor fixing portion, A plurality of upper reinforcing ribs are provided on the upper surface of the connecting wall, the upper reinforcing ribs standing upward and extending in the front-rear direction, spaced apart in the vehicle width direction, An upper extension rib that is continuous with the upper reinforcement rib is provided on the upper surface of the floor fixing portion, A lower rib is provided on the underside of the floor fixing portion, and the lower rib has a plurality of rib elements that protrude downward and extend in multiple directions. A vehicle body front structure, characterized in that the protruding height of the upper extension rib is set higher than the protruding height of the lower rib.

2. 2. The vehicle body front structure according to claim 1, wherein the connecting wall is provided with a panel fixing portion that is fixed to the dashboard lower panel above the upper reinforcing rib.

3. The vehicle front structure according to claim 1, characterized in that the lower rib, which is arranged in an area close to the vehicle width end of the floor fixing portion, is set so that the extension direction of the rib element does not face the vehicle width direction.

Images