Dash panel and front body structure

Abstract

To improve proof stress of a dash panel single body.SOLUTION: A dash panel 10 of a vehicle is provided with a front wall 11, a bottom wall 12, a wheel arch part 13, an opening part 14, a flange 15, and a first ridge line part 41. The flange 15 projects on an in-vehicle side from the front wall 11 and the bottom wall 12 around the opening part 14. The first ridge line part 41 is formed so as to continue to a periphery of the flange 15 between the front wall 11 and the flange 15 and between the bottom wall 12 and the flange 15.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a dash panel and a vehicle front body structure for an automobile. [Background technology]

[0002] Autonomous driving technology, which has been developed in recent years, requires the installation of sensors and cameras to recognize road conditions and pedestrians, as well as electronic devices for image processing, which increases the weight of the vehicle.In addition, in recent years, there has been a trend in vehicle design to increase the size of vehicles in order to expand the interior space in order to improve passenger comfort, which also causes an increase in vehicle weight.

[0003] In order to ensure the vehicle's crashworthiness under these circumstances, it is essential to increase the thickness of structural components. In particular, to improve the vehicle's crashworthiness in a frontal collision, it is necessary to increase the thickness of relatively large components such as front side members, which has a significant impact on the weight of the vehicle body. Therefore, efforts are being made to increase the strength of inner panels in order to prevent the thickness of structural components from increasing.

[0004] One example of such an interior panel is the dash panel. The dash panel is located near the feet of occupants (driver and front passenger) and plays a role in distributing the collision load from the front side members to the side sills and floor tunnel in the event of a frontal collision. For this reason, from the perspective of occupant protection, it is desirable to increase the strength of the dash panel.

[0005] As a technology relating to dash panels, Patent Document 1 discloses a vehicle front structure in which the dash panel, floor panel, and floor tunnel are reinforced with reinforcing members. Also, Patent Document 2 discloses a vehicle front structure that focuses on the joining structure between the dash panel and the front pillar. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2013 / 080305 [Patent Document 2] Patent No. 6076774 Summary of the Invention [Problem to be solved by the invention]

[0007] In order to increase the strength of the dash panel while suppressing an increase in vehicle weight, it is desirable to increase the strength of the dash panel itself. However, the vehicle body front structure described in Patent Document 1 is a structure that uses reinforcing members to improve collision performance, so an increase in weight due to the reinforcing members is unavoidable. In addition, the vehicle body front structure described in Patent Document 2 is a structure that increases rigidity against inputs in the vehicle length direction and the ability to absorb loads from above the vehicle without using reinforcing members, but does not consider increasing the strength of the dash panel itself.

[0008] The present invention has been made in view of the above circumstances, and has an object to improve the bearing strength of a dash panel alone. [Means for solving the problem]

[0009] One aspect of the present invention that solves the above problem is a dash panel for an automobile, comprising a front wall, a bottom wall, a wheel arch portion, an opening, a flange, and a first ridge portion, wherein the front wall is a wall portion that extends in the vehicle height direction and the vehicle width direction, the bottom wall is a wall portion that extends in the vehicle length direction and the vehicle width direction, the wheel arch portions are formed at both ends of the dash panel in the vehicle width direction, the opening is formed in the center of the dash panel in the vehicle width direction, from the midpoint in the vehicle height direction to the rear end in the vehicle length direction, the flange protrudes from the front wall and the bottom wall toward the vehicle interior around the opening, and the first ridge portion is formed continuously around the flange between the front wall and the flange and between the bottom wall and the flange. The first ridge portion is a bent portion in which the radius of curvature at the boundary between two adjacent surfaces is 25 to 70 mm, and the opening angle between the two adjacent surfaces is 145° or less. It is characterized by the following.

[0010] Another aspect of the present invention is a front body structure for an automobile, characterized by comprising the above-mentioned dash panel, a front side member attached to the dash panel, and a floor panel joined to the dash panel. [Effects of the Invention]

[0011] According to the present invention, the bearing strength of the dash panel alone can be improved. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is an explanatory diagram showing a schematic configuration of a vehicle body front structure according to a first embodiment of the present invention. [Figure 2] This is a view of the dash panel alone as seen from inside the vehicle. [Figure 3] This is a view of the dash panel alone as seen from outside the vehicle. [Figure 4] FIG. 3 is a view showing a cross section II of FIG. 2. [Figure 5] FIG. 10 is an explanatory diagram for explaining the definition of a ridge line portion. [Figure 6] FIG. 6 is an explanatory diagram showing a schematic configuration of a vehicle front body structure according to a second embodiment of the present invention. [Figure 7] This is a view of the dash panel alone as seen from inside the vehicle. [Figure 8] This is a view of the dash panel alone as seen from outside the vehicle. [Figure 9] FIG. 8 is a cross-sectional view taken along line II-II of FIG. 7. [Figure 10] FIG. 10 is an explanatory diagram for explaining the definition of a representative length of a convex portion. [Figure 11] FIG. 2 is an explanatory diagram showing the first surface portion (the surface on which the convex portions are formed) viewed from a direction perpendicular to the first surface portion. [Figure 12] 12 is an explanatory diagram for explaining the intervals between the convex portions, and is a cross-sectional view taken along line III-III in FIG. 11. FIG. [Figure 13] FIG. 10 is a diagram showing the results of simulation (1). [Figure 14] FIG. 10 is a diagram showing the results of simulation (1). [Figure 15] FIG. 10 is a diagram showing the results of simulation (2). DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this specification and the drawings, elements having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0014] First Embodiment 1 is an explanatory diagram showing a schematic configuration of a vehicle body front structure according to a first embodiment. In this specification and the drawings, the X direction is the vehicle length direction, the Y direction is the vehicle width direction, and the Z direction is the vehicle height direction.

[0015] The vehicle body front structure 1 includes a dash panel 10, a front side member 20, and a floor panel 30.

[0016] The dash panel 10 is a partition wall located between the engine compartment (not shown) and the interior space of the vehicle. In this specification, the term "dash panel" refers to a component formed by processing (e.g., pressing) a single sheet of plate material, and does not include a structure that functions as a dash panel by combining multiple components.

[0017] The material of dash panel 10 is not particularly limited, and may be, for example, a metal material such as a steel plate having a tensile strength of 270 MPa or more, or a metal material such as an aluminum alloy member or a magnesium alloy member. When a steel plate is used as the material of dash panel 10, the tensile strength of the steel plate is more preferably 440 MPa or more, and even more preferably 590 MPa or more or 780 MPa or more. The thickness of dash panel 10 is, for example, 0.8 to 5 mm.

[0018] The configuration of the dash panel 10 according to the first embodiment will be described in detail below. Fig. 2 is a view of the dash panel alone as seen from the inside of the vehicle. Fig. 3 is a view of the dash panel alone as seen from the outside of the vehicle. Fig. 4 is a view of a cross section taken along line II in Fig. 2.

[0019] The dash panel 10 has a front wall 11, a bottom wall 12, a wheel arch portion 13, an opening 14, and a flange 15.

[0020] The front wall 11 is a wall portion facing the engine compartment and extending in the vehicle height direction (Z direction) and the vehicle width direction (Y direction). The front wall 11 has a first surface portion 11a, a second surface portion 11b, and a third surface portion 11c.

[0021] The first surface portion 11a is a wall portion on which a convex portion 50, which will be described later, is formed. The second surface portion 11b is a wall portion that is recessed forward in the vehicle length direction (X direction) relative to the first surface portion 11a, at the center of the first surface portion 11a in the vehicle width direction (Y direction). In this embodiment, both the first surface portion 11a and the second surface portion 11b are flat, but may have curved surfaces depending on the vehicle body structure. Also, depending on the vehicle body structure, the second surface portion 11b may not exist, and the area of ​​the second surface portion 11b may be formed by the first surface portion 11a.

[0022] The third surface portion 11c is a wall portion for attaching the front side member 20, and is located below the first surface portion 11a. The area indicated by the two-dot chain line in the plane of the third surface portion 11c in Fig. 3 is the attachment surface 21 between the dash panel 10 and the front side member 20. The dash panel 10 and the front side member 20 are joined by welding means such as spot welding.

[0023] The mounting surface 21 is preferably a plane (vertical plane) perpendicular to the horizontal plane. This makes it easier to maintain the posture of the front side member 20 when an axial load is input from the front of the front side member 20 mounted on the mounting surface 21, thereby increasing the strength of the vehicle front body structure 1.

[0024] The bottom wall 12 is a wall portion extending in the vehicle length direction (X direction) and the vehicle width direction (Y direction), and is joined to the floor panel 30. The bottom wall 12 has an inclined surface portion 12a and a joining surface portion 12b.

[0025] The inclined surface portion 12a is a portion that connects to the front wall 11, and the joint surface portion 12b is a portion that is joined to the floor panel 30 near the rear end in the vehicle length direction. The joint surface portion 12b and the floor panel 30 are joined by welding means such as spot welding. In this embodiment, the joint surface portion 12b is a substantially horizontal surface.

[0026] As shown in Figures 2 and 3, the wheel arch portion 13 is a portion that surrounds the periphery of a tire (not shown) at both ends in the vehicle width direction (Y direction), and has a shape that bulges out towards the inside of the vehicle so as not to interfere with the tire.

[0027] Opening 14 is provided so that dash panel 10 does not interfere with a floor tunnel (not shown). Opening 14 is formed in the center of dash panel 10 in the vehicle width direction (Y direction), from the middle in the vehicle height direction (Z direction) to the rear end in the vehicle length direction (X direction).

[0028] Flange 15 is formed by processing a single plate material and is provided so as to surround the periphery of opening 14. This flange 15 has a shape that protrudes toward the vehicle interior from each of the first surface portion 11a and the third surface portion 11c of front wall 11 and the inclined surface portion 12a and the joint surface portion 12b of bottom wall 12.

[0029] As shown in FIG. 3, in the dash panel 10, a first ridge portion 41, a second ridge portion 42, and a third ridge portion 43 are provided between each wall portion of the front wall 11, the bottom wall 12, and the wheel arch portion 13.

[0030] The first ridge portion 41 is a ridge portion located between the front wall 11 and the flange 15, and between the bottom wall 12 and the flange 15. In other words, the first ridge portion 41 is a ridge portion that is sandwiched between the flange 15 and each of the wall portions of the first surface portion 11a and the third surface portion 11c of the front wall 11, and also between the flange 15 and the inclined surface portion 12a of the bottom wall 12. The first ridge portion 41 is formed continuously around the periphery of the flange 15 so as to follow the shape of the flange 15, and is curved three-dimensionally.

[0031] The second ridge portion 42 is a ridge portion that is continuously formed between the front wall 11 and the wheel arch portion 13, and between the bottom wall 12 and the wheel arch portion 13. In other words, the second ridge portion 42 is a ridge portion that is sandwiched between the wheel arch portion 13 and each of the wall portions of the first surface portion 11a and the third surface portion 11c of the front wall 11, and is also sandwiched between the inclined surface portion 12a of the bottom wall 12 and the wheel arch portion 13.

[0032] The third ridge portion 43 is a ridge portion located between the first ridge portion 41 and the second ridge portion 42. In other words, the third ridge portion 43 is a ridge portion sandwiched between the third surface portion 11c of the front wall 11 and the inclined surface portion 12a of the bottom wall 12. The third ridge portion 43 is formed continuously from the first ridge portion 41 to the second ridge portion 42 so as to connect the first ridge portion 41 and the second ridge portion 42.

[0033] In this specification, the term "ridge line" refers to a bent portion at the boundary between adjacent surfaces A and B, where the radius of curvature R is 25 to 70 mm and the opening angle θ between surfaces A and B is 145° or less, as shown in Fig. 5. A bent portion that satisfies these conditions contributes to improving the surface rigidity of each of the adjacent surfaces A and B.

[0034] Whether a bent portion between two adjacent surfaces is a ridge portion is determined as follows: For example, in the bent portion at point P1 shown in Fig. 3, the two adjacent surfaces are the third surface portion 11c of the front wall 11 and the inclined surface portion 12a of the bottom wall 12. If the radius of curvature of the bent portion at the boundary between these two surfaces 11c and 12a is 25 to 70 mm and the opening angle between the two surfaces 11c and 12a is 145° or less, the bent portion is determined to be a ridge portion.

[0035] At point P2, the two adjacent surfaces are the third surface portion 11c of the front wall 11 and the flange 15, and whether or not the bent portion is a ridgeline portion is determined based on the radius of curvature of the bent portion at the boundary between these two surfaces 11c, 15 and the opening angle between the two surfaces 11c, 15. At point P3, the two adjacent surfaces are the inclined surface portion 12a of the bottom wall 12 and the flange 15, and whether or not the bent portion is a ridgeline portion is determined based on the radius of curvature of the bent portion at the boundary between these two surfaces 12a, 15 and the opening angle between the two surfaces 12a, 15.

[0036] In addition, in this specification, the phrase "a continuous ridge line" refers to a state in which the ridge line extends continuously without interruption. For example, in the first ridge line 41 shown in FIG. 3, if an opening (not shown) is provided in a partial region between the third surface portion 11c and the flange 15, the ridge line on either side of the opening is in an interrupted state. In other words, in that case, there is no "ridge line that is continuous around the flange 15."

[0037] The outline of the structure of the dash panel 10 has been described above.

[0038] In dash panel 10 according to this embodiment, first ridge portion 41 is formed continuously across front wall 11 and bottom wall 12. As a result, when an axial load is input from front side member 20 to front wall 11, the restraining force from flange 15 and first ridge portion 41 increases, thereby increasing the surface rigidity of front wall 11 and bottom wall 12 in the vicinity of flange 15. As a result, deformation of front wall 11 and bottom wall 12 in the vicinity of flange 15 can be suppressed during a frontal collision, improving the strength of dash panel 10 as a single unit.

[0039] Furthermore, since the strength of dash panel 10 alone can be improved without providing a reinforcing member (not shown), the weight of the reinforcing member can be reduced by the weight of the vehicle body front structure 1. In addition, by not providing a reinforcing member, the foot space for occupants can be expanded by the thickness of the reinforcing member, improving comfort inside the vehicle.

[0040] Furthermore, in the event of a frontal collision, when an axial load is input to the front side member 20, the dash panel 10 is less likely to deform, so that the front side member 20 joined to the dash panel 10 is more likely to maintain its original posture. This allows the front side member 20 to bear a greater load. In addition, because the dash panel 10 is less likely to deform, the transmission efficiency of the collision load transmitted from the front side member 20 to the side sill (not shown) and floor tunnel (not shown) can be increased, improving the strength of the vehicle front body structure 1.

[0041] In dash panel 10 according to this embodiment, in addition to first ridgeline 41, second ridgeline 42 and third ridgeline 43 are provided, which improves the surface rigidity of each wall portion adjacent to each of ridgelines 41 to 43. In other words, the surface rigidity of dash panel 10 as a whole is improved, which further improves crash resistance and quietness compared to when only first ridgeline 41 is provided.

[0042] 3, the mounting surface 21 of the front side member 20 is preferably located between the first ridge line 41 and the second ridge line 42 and above the third ridge line 43. The area near the first ridge line 41 to the third ridge line 43 has particularly high surface rigidity, and therefore, by mounting the front side member 20 in this area, the effect of maintaining the posture of the front side member 20 during a frontal collision is enhanced.

[0043] Second Embodiment Fig. 6 is an explanatory diagram showing a schematic configuration of a vehicle body front structure according to a second embodiment. Fig. 7 is a diagram showing the dash panel alone as viewed from the inside of the vehicle. Fig. 8 is a diagram showing the dash panel alone as viewed from the outside of the vehicle. Fig. 9 is a diagram showing a cross section taken along line II-II in Fig. 7.

[0044] In the vehicle body front structure 1 according to the second embodiment, a plurality of protrusions 50 (bead portions) are provided on the first surface portion 11a of the front wall 11 of the dash panel 10 according to the first embodiment.

[0045] The protrusion 50 has a shape that protrudes forward in the vehicle length direction relative to the first surface portion 11a. Note that the protrusion 50 may also have a shape that protrudes rearward in the vehicle length direction relative to the first surface portion 11a.

[0046] The protrusions 50 are formed in a diamond shape when viewed from a direction perpendicular to the first surface 11a. However, the protrusions 50 may be, for example, a trapezoid or a parallelogram, and are not limited to a rectangle but may also be a polygon or a circle such as a perfect circle or an ellipse. Furthermore, there are no particular limitations on the arrangement of the multiple protrusions 50.

[0047] The first surface portion 11a has a relatively large area compared to the other second surface portion 11b and third surface portion 11c, and occupies the majority of the area of ​​the entire front wall 11. In such a first surface portion 11a, vibrations are likely to occur starting from the flat area, and road noise from the front upper mount (not shown) is likely to be transmitted.

[0048] On the other hand, if multiple protrusions 50 as described above are provided, the number of continuous flat areas within the surface of first surface portion 11a is reduced, thereby increasing the surface rigidity of first surface portion 11a. This increases the vibration suppression effect of dash panel 10 and improves quietness inside the vehicle. That is, according to dash panel 10 of the second embodiment, in addition to the effect of improving the strength of dash panel 10 itself as described in the first embodiment, the effect of improving quietness inside the vehicle is also achieved.

[0049] Furthermore, the vehicle body front structure 1 having the dash panel 10 of the second embodiment is provided with a plurality of protrusions 50 spaced apart on the front wall 11, thereby reducing the equivalent radiation power, enhancing the noise and vibration suppression effect, and improving the quietness inside the vehicle.

[0050] A preferred arrangement of the protrusions will be described below. In this description, the representative length of the protrusions 50 will first be described. Figure 10 is an explanatory diagram for explaining the definition of the representative length of the protrusions 50.

[0051] The representative length is the length from the center of gravity of the top surface 51 to the outer edge of the protrusion 50 that is farthest when the protrusion 50 is viewed from a direction perpendicular to the top surface 51 of the protrusion 50. For example, as shown in FIG. 10(a), if the protrusion 50 is circular, the radius of the circle is the representative length, and as shown in FIG. 10(b), if the protrusion 50 is elliptical, the semi-major axis of the ellipse is the representative length. Also, as shown in FIGS. 10(a) and 10(b), if the protrusion 50 is a regular polygon, the length from the center of gravity of the top surface 51 to the vertex is the representative length.

[0052] Regarding a preferred arrangement of the protrusions 50, FIG. 11 is an explanatory diagram of the first surface 11a viewed from a direction perpendicular to the first surface 11a (the surface on which the protrusions 50 are formed).

[0053] The plurality of protrusions 50 are preferably arranged such that the representative lengths of the plurality of protrusions 50 are aligned in at least one direction when viewed from a direction perpendicular to the first surface portion 11a.

[0054] 11, each of the protrusions 50 has a regular quadrilateral shape, and therefore the representative length of each of the protrusions 50 is the length from the center of the diagonal to one of the vertices. That is, the direction of the representative length of each of the protrusions 50 is the direction from the center of the diagonal to one of the vertices.

[0055] Direction D shown in Figure 11 A The Z direction (in this embodiment) is a direction that coincides with the direction of the representative length of the plurality of protrusions 50, and the direction of the representative length of the plurality of protrusions 50 is the same as this direction D A 11, since the protrusion 50 has a square shape, there are multiple directions of the representative length. B (Y direction in this embodiment) is the above direction D A This direction is different from BThis is also the direction of the representative length of the plurality of protrusions 50.

[0056] 11, the plurality of protrusions 50 are arranged so that the representative lengths thereof are aligned in two directions. When the representative lengths of the plurality of protrusions 50 are aligned in at least one direction, the arrangement of the plurality of protrusions 50 becomes more regular, and variations in the surface rigidity of the first surface portion 11a can be reduced. To further enhance this effect, it is preferable that the representative lengths of all of the protrusions 50 are aligned in at least one direction.

[0057] In addition, the direction D shown in Figure 11 C is a direction that is not related to the representative length of each protrusion 50, so this direction D C is not a direction in which the representative lengths of the plurality of protrusions 50 are the same.

[0058] From the viewpoint of further increasing the surface rigidity of the first surface portion 11a, it is preferable that the surface occupancy rate of the protrusions 50 on the first surface portion 11a be 25% or more. The surface occupancy rate is a value calculated by "total area of ​​the top surfaces of the plurality of protrusions 50 / area of ​​the surface on the front wall 11 on which the plurality of protrusions 50 are formed."

[0059] More specifically, as shown in FIG. 11, the areas of the top surfaces of the protrusions 50 are S1, S2, S3, . . . S n-1 , S n The sum of these is the "total area of ​​the top surface of the plurality of protrusions 50" mentioned above. Furthermore, the "area of ​​the surface on which the plurality of protrusions 50 are formed" is the area of ​​the first surface 11a. Note that the area of ​​the first surface 11a is the area when the first surface 11a is flat and does not have the plurality of protrusions 50 formed thereon. Furthermore, the second surface 11b, which does not exist within the plane of the first surface 11a, is not a surface on which the plurality of protrusions 50 are formed, and therefore the area of ​​the second surface 11b is not included in the "area of ​​the surface on which the plurality of protrusions 50 are formed."

[0060] From the viewpoint of increasing the surface rigidity of the first surface portion 11a, the surface occupancy of the above-mentioned protrusions 50 is more preferably 40% or more, and even more preferably 50% or 60% or more. On the other hand, although there is no particular upper limit to the surface occupancy, from the viewpoint of facilitating the molding of the protrusions 50, the surface occupancy is preferably 90% or less, and more preferably 80% or less.

[0061] 12 is an explanatory diagram for explaining the intervals between the plurality of protrusions 50, and is a diagram showing a cross section taken along the line III-III in FIG. 11. In detail, FIG. 12 shows the direction in which the representative lengths of the plurality of protrusions 50 are aligned (direction D in FIG. 11). A or direction D B 1 is a view of the first surface portion 11a cut in a direction perpendicular to the first surface portion 11a so as to include the first surface portion 11a.

[0062] Regarding the spacing between the protrusions 50, in the cross section shown in FIG. 12, the ratio (d1 / d2) of the length d1 of the top surface of the protrusion 50 to the spacing d2 between that protrusion 50 and the adjacent protrusion 50 is preferably 1.5 to 2.5. Furthermore, the representative length L of the protrusions 50 is preferably 4 to 20 mm. By satisfying these conditions, the protrusions 50 can be arranged in a well-balanced manner over the entire first surface 11a, and the flat area on the top surface 51 of the protrusions 50 and the flat area of ​​the first surface 11a between the protrusions 50 can be reduced. This increases the surface rigidity of the entire first surface 11a.

[0063] While one embodiment of the present invention has been described above, the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the technical ideas set forth in the claims, and it is understood that such modifications also fall within the technical scope of the present invention.

[0064] For example, in the above embodiment, the vehicle body front structure 1 is illustrated as being configured without a reinforcing member (not shown) in the dash panel 10, but as long as the weight requirements of the product and specifications such as the size of the interior space can be met, a reinforcing member may be provided in the dash panel 10. Even in this case, the effect of improving the bearing strength of the dash panel 10 itself can still be obtained. [Example]

[0065] <Simulation (1)> In order to confirm the collision performance of the dash panel according to the embodiment of the present invention, a collision simulation was carried out using an analytical model in which a dash panel having the structure shown in Fig. 8 was mounted on a vehicle model. This simulation was an analysis simulating a full-lap test, and was carried out under the conditions that the vehicle speed was 56 km / h, the barrier was a rigid wall, and the material was a steel plate.

[0066] As a comparative example for performance comparison, a simulation was also carried out on a vehicle model equipped with a dash panel of a conventional structure. The conventional structure in this simulation is a structure having only the second ridge line portion among the first to third ridge line portions described in the above embodiment.

[0067] Figure 13 shows the results of the simulation, including the maximum load of the floor tunnel of the vehicle model. Figure 14 shows the results of the simulation, including the amount of setback of the dash panel. Note that the simulations in Figures 13 and 14 were performed using models with different tensile strengths of materials: 270 MPa and 1180 MPa.

[0068] As shown in Figure 13, the structure of the example has a larger maximum load on the floor tunnel than the structure of the comparative example, and the bearing strength of the dash panel is improved, and it is understood that a larger load is transmitted to the floor tunnel. Also, as shown in Figure 14, the structure of the example has a smaller setback amount of the dash panel than the structure of the comparative example, and it is also understood that the safety of the occupants is improved.

[0069] Furthermore, when comparing the results of the Examples and Comparative Examples when the tensile strength is 270 MPa with the results of the Examples and Comparative Examples when the tensile strength is 1180 MPa, the improvement in the effect of the Examples over the Comparative Examples is greater when the tensile strength is 1180 MPa. In other words, the structure according to the Examples of the present invention is useful when applied to higher strength materials, which effectively increases the strength of the dash panel 10 alone.

[0070] <Simulation (2)> A simulation was carried out to simulate a measurement test of equivalent radiation power. This simulation was carried out under the condition that the front upper mount was vibrated for the vehicle models of the example and comparative example in simulation (1). The results are shown in Figure 15.

[0071] 15, the structure of the example has a lower equivalent radiation power in the frequency bands of 200 to 250 Hz and 300 to 350 Hz than the structure of the comparative example. That is, it can be seen that the structure of the example improves quietness inside the vehicle.

[0072] The above describes an embodiment of the present invention. In the above description, several dash panel configurations have been exemplified, but the configurations of the dash panels can be arbitrarily combined as long as the function of the dash panel is not impaired.

[0073] For example, the following configurations also fall within the technical scope of the present invention. [1] A dash panel for an automobile, a front wall, a bottom wall, a wheel arch portion, an opening, a flange, and a first ridge portion; the front wall is a wall portion extending in a vehicle height direction and a vehicle width direction, the bottom wall is a wall portion extending in the vehicle length direction and the vehicle width direction, The wheel arch portions are formed at both ends of the dash panel in a vehicle width direction, The opening is formed in a center portion of the dash panel in a vehicle width direction, from a midpoint in a vehicle height direction to a rear end in a vehicle length direction, the flanges protrude from the front wall and the bottom wall toward the vehicle interior around the opening, The dash panel is characterized in that the first ridge portion is formed continuously around the flange between the front wall and the flange and between the bottom wall and the flange. [2] A second ridge portion and a third ridge portion are provided, the second ridge line portion is formed continuously between the front wall and the wheel arch portion and between the bottom wall and the wheel arch portion, The dash panel according to [1], wherein the third ridge portion extends from the first ridge portion to the second ridge portion. [3] The front wall has a mounting surface to which a front side member is attached, The dash panel described in [2] is characterized in that the mounting surface is located between the first ridge portion and the second ridge portion and above the third ridge portion. [4] The dash panel according to [3], wherein the mounting surface is a surface perpendicular to a horizontal plane. [5] The dash panel according to any one of [1] to [4], wherein the front wall has a plurality of protrusions protruding in a direction perpendicular to the front wall. [6] The dash panel described in [5], characterized in that the plurality of protrusions are arranged so that the representative length directions of the plurality of protrusions are aligned in at least one direction when viewed from a direction perpendicular to the surface on which the protrusions are formed. [7] The dash panel described in [6], characterized in that the surface occupancy rate of the convex portions calculated by "total area of ​​the top surfaces of the plurality of convex portions / area of ​​the surface on which the plurality of convex portions are formed in the front wall" is 25% or more. [8] In a cross section perpendicular to the surface on which the protrusions are formed, cut so as to include a direction in which the representative lengths of the plurality of protrusions are aligned, the ratio (d1 / d2) of the top surface length d1 of the protrusion to the distance d2 between the protrusion and an adjacent protrusion is 1.5 to 2.5, The dash panel according to [6] or [7], wherein the representative length of the protrusion is 4 to 20 mm. [9] The dash panel according to any one of [1] to [8], characterized in that it is formed from a steel plate having a tensile strength of 590 MPa or more.

[10] A front body structure of an automobile, [1] to [9], and a dash panel according to any one of [1] to [9]. a front side member attached to the dash panel; a floor panel joined to the dash panel.

[0074] In the dash panel described above, the provision of the first ridge line portion was essential from the perspective of solving the problem of improving the strength of the dash panel alone. However, from the perspective of solving the problem of improving quietness inside the vehicle, the provision of the convex portion is essential, but the provision of the first ridge line portion is not essential. In other words, the following exemplary embodiments of the invention may be used to solve the problem of improving quietness inside the vehicle.

[0075] [1] A dash panel for an automobile, a front wall, a bottom wall, a wheel arch portion, an opening, a flange, and a first ridge portion; the front wall is a wall portion extending in a vehicle height direction and a vehicle width direction, the bottom wall is a wall portion extending in the vehicle length direction and the vehicle width direction, The wheel arch portions are formed at both ends of the dash panel in a vehicle width direction, The dash panel is characterized in that the front wall has a plurality of protrusions protruding in a direction perpendicular to the front wall. [2] The dash panel described in [1], characterized in that the plurality of protrusions are arranged so that the representative length directions of the plurality of protrusions are aligned in at least one direction when viewed from a direction perpendicular to the surface on which the protrusions are formed. [3] The dash panel described in [1] or [2], characterized in that the surface occupancy rate of the convex portions calculated by "total area of ​​the top surfaces of the plurality of convex portions / area of ​​the surface on which the plurality of convex portions are formed in the front wall" is 25% or more. [4] In a cross section perpendicular to the surface on which the protrusions are formed, cut so as to include a direction in which the representative lengths of the plurality of protrusions are aligned, the ratio (d1 / d2) of the top surface length d1 of the protrusion to the distance d2 between the protrusion and an adjacent protrusion is 1.5 to 2.5, The dash panel according to any one of [1] to [3], wherein the representative length of the protrusion is 4 to 20 mm. [5] The dash panel according to any one of [1] to [4], characterized in that it is formed from a steel plate having a tensile strength of 590 MPa or more. [6] A front body structure of an automobile, A dash panel according to any one of [1] to [5]; a front side member attached to the dash panel; a floor panel joined to the dash panel. [Industrial Applicability]

[0076] The present invention is applicable to the dash panel of an automobile. [Explanation of symbols]

[0077] 1 Front body structure 10 Dash Panel 11 Front wall 11a First side 11b Second side part 11c Third side 12 Bottom wall 12a Slope section 12b Joint surface part 13 Wheel arch 14 Openings 15 flange 20 Front side member 21 Front side member mounting surface 30 Floor Panel 41 First Ridge 42 Second Ridge 43 Third Ridge 50 convex part 51 Top surface of the convex part d1 Length of the top of the convex part d2 Spacing of convex parts A side B side L: characteristic length of the convex part S Area of ​​the top surface of the convex part R Radius of curvature of the ridge θ Opening angle of the ridge

Claims

1. A dash panel for an automobile, a front wall, a bottom wall, a wheel arch portion, an opening, a flange, and a first ridge portion; the front wall is a wall portion extending in a vehicle height direction and a vehicle width direction, the bottom wall is a wall portion extending in the vehicle length direction and the vehicle width direction, The wheel arch portions are formed at both ends of the dash panel in a vehicle width direction, The opening is formed in a center portion of the dash panel in a vehicle width direction, from a midpoint in a vehicle height direction to a rear end in a vehicle length direction, the flanges protrude from the front wall and the bottom wall toward the vehicle interior around the opening, the first ridge portion is formed continuously around the flange between the front wall and the flange and between the bottom wall and the flange, The first ridge portion is a bent portion having a radius of curvature of 25 to 70 mm at the boundary between two adjacent surfaces and an opening angle of the two adjacent surfaces of 145° or less.

2. A second ridge portion and a third ridge portion are provided, the second ridge line portion is formed continuously between the front wall and the wheel arch portion and between the bottom wall and the wheel arch portion, 2. The dash panel according to claim 1, wherein the third ridge portion extends from the first ridge portion to the second ridge portion.

3. the front wall has a mounting surface to which a front side member is attached, 3. The dash panel according to claim 2, wherein the mounting surface is located between the first ridgeline portion and the second ridgeline portion and above the third ridgeline portion.

4. 4. The dash panel according to claim 3, wherein the mounting surface is a surface perpendicular to a horizontal plane.

5. 5. The dash panel according to claim 1, wherein the front wall has a plurality of protrusions that protrude in a direction perpendicular to the front wall.

6. 6. The dash panel according to claim 5, wherein the plurality of protrusions are arranged such that, when viewed from a direction perpendicular to the surface on which the protrusions are formed, the directions of the representative lengths of the plurality of protrusions are aligned in at least one direction.

7. 7. The dash panel according to claim 6, wherein a surface occupancy rate of the protrusions calculated by dividing the total area of ​​the top surfaces of the plurality of protrusions by the area of ​​the surface of the front wall on which the plurality of protrusions are formed is 25% or more.

8. In a cross section perpendicular to the surface on which the protrusions are formed, the cross section is cut so as to include a direction in which the representative lengths of the plurality of protrusions are aligned, and the top surface length d of the protrusions is 1 and the distance d between the protrusion and the adjacent protrusion 2 The ratio (d 1 / d 2 ) is 1.5 to 2.5, 7. The dash panel according to claim 6, wherein the representative length of the protrusion is 4 to 20 mm.

9. The dash panel according to any one of claims 1 to 4, characterized in that it is formed from a steel plate having a tensile strength of 590 MPa or more.

10. A front body structure of an automobile, A dash panel according to any one of claims 1 to 4; a front side member attached to the dash panel; a floor panel joined to the dash panel.

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