JP2016078563A - Vehicle front structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle front structure in which, folded width of an energy absorption member is wider on a lower side than on an upper side.SOLUTION: A vehicle front structure comprises: a front bumper cross member 4 forming a front bumper extending in a vehicle width direction on a front part of a vehicle; and an energy absorption member 5 fixed to a front face of the front bumper cross member 4 and having a polygonal closed cross sectional shape which is collapsed when the vehicle collides by head-on collision. The energy absorption member 5 comprises: a fixing side plate 51 having a front face plate part 51a arranged along the front face of the front bumper cross member 4, and a rear plate part 51b arranged and extending from the front face plate part to rearward in a lower region of the front bumper cross member 4; and an absorption side plate 52 having an upper side plate part 52d jointed to the front face plate part 51a and extending forward, a lower side plate part 52e jointed to the rear plate part 51b and extending forward, and a pressure reception plate part 52a disposed between a front end of the upper side plate part 52d and a front end of teh lower side plate part 52e in parallel to the front face plate part 51a.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a vehicle front structure of an automobile, and more specifically to a vehicle front structure that can reduce damage to a pedestrian in an accident in which an automobile collides with a pedestrian.

In recent traffic accidents, with the increasing proportion of accidents involving pedestrians, there is a need to reduce pedestrian damage in accidents where automobiles collide with pedestrians.
A vehicle front structure including a front bumper cross member fixed to the front portion of the vehicle and an energy absorbing member fixed to the front surface of the front bumper cross member is known as a means for reducing pedestrian damage. The front bumper cross member is a vehicle body member extending along the vehicle width direction intersecting with the vehicle traveling direction, and has a cross section with high rigidity. The energy absorbing member is for reducing a pedestrian's fracture risk and ligament damage risk, and has a polygonal closed cross-sectional shape that collapses when the vehicle collides front. The polygonal closed cross-sectional shape of the energy absorbing member is usually formed vertically symmetrically, and when the automobile collides with the front, it is bent and crushed so as to protrude symmetrically. (For example, refer to Patent Document 1 and Patent Document 2).

JP2013-52760A JP 2010-195228 A

However, when a vehicle-mounted component is installed in the upper region of the energy absorbing member, it may be desired that the bent width of the energy absorbing member is wider on the lower side than on the upper side.
In view of the above circumstances, an object of the present invention is to provide a vehicle body front structure in which the bending width of an energy absorbing member is wider on the lower side than on the upper side.

  The present invention includes a front bumper cross member constituting a front bumper extending in a vehicle width direction at a vehicle front portion, and a polygonal closed cross section fixed to the front surface of the front bumper cross member and crushed when the vehicle collides front. An energy absorbing member having a shape, wherein the energy absorbing member is disposed on the front surface of the front bumper cross member, and the rear surface of the front bumper cross member is rearward from the front surface plate portion. A fixed side plate having a rear plate portion arranged to extend to, an upper plate portion joined to the front plate portion and extending forward, a lower plate portion joined to the rear plate portion and extending forward, And an absorption side plate having a pressure receiving plate portion disposed in parallel with the front plate portion between the front end of the upper plate portion and the front end of the lower plate portion.

  According to the present invention, the energy absorbing member includes a front plate portion arranged along the front surface of the front bumper cross member, and a rear plate portion arranged extending rearward from the front plate portion in a lower region of the front bumper cross member. A fixed side plate having an upper plate portion joined to the front plate portion and extending forward, a lower plate portion joined to the rear plate portion and extending forward, and a front end of the upper plate portion and a front end of the lower plate portion. Since the absorption side plate having the pressure receiving plate portion disposed in parallel with the front plate portion is included, the lower side plate portion of the absorption side plate is wider than the upper side plate portion. Thereby, when a vehicle collides with the front, the bending width becomes wider at the lower plate portion that is wider than the upper plate portion, and the bending width of the energy absorbing member becomes wider below the upper side.

In one aspect of the present invention, the upper plate portion has a first inflection point that forms a first ridge line in the vehicle width direction, and the lower plate portion has a second ridge line in the vehicle width direction. The second inflection point is arranged, and the position of the second inflection point is arranged behind the position of the first inflection point.
In this way, when the vehicle collides with the front, the upper plate portion is bent at the first inflection point forming the first ridge line, and the lower plate portion is disposed behind the first inflection point. Bends at the second inflection point forming the second ridge line. Thereby, when the vehicle collides with the front, the bending width of the energy absorbing member becomes wider on the lower side than on the upper side.

In one aspect of the present invention, the first inflection point is located above a straight line connecting a connection point between the front end of the upper plate portion and the front plate portion of the upper plate portion, and the second inflection point. The inflection point is positioned below a straight line connecting the connection points between the front end of the lower plate portion and the rear plate portion of the lower plate portion.
In this way, when the vehicle collides with the front, the upper plate portion is bent so as to protrude upward at the first inflection point forming the first ridge line, and the lower plate portion has the second ridge line. The second inflection point to be formed is bent so as to protrude downward. Thereby, when a vehicle collides with the front, the absorption side plate is surely bent, and the energy absorbing member is crushed as set.

In one aspect of the present invention, the length of the lower plate portion is longer than the length of the upper plate portion.
In this way, when the vehicle collides with the front, it first bends at the upper plate and then bends at the lower plate, so the bending width of the lower plate is wider than the bending width of the upper plate, thereby absorbing energy. The bending width of the member is wider on the lower side than on the upper side.

In one aspect of the present invention, the polygonal closed cross-sectional shape of the energy absorbing member formed on the front surface of the front bumper cross member is a pentagonal shape in which the front side, the rear side, the upper side, and the lower side piece are narrow in front. It is.
In this way, when the vehicle collides with the front, the energy absorbing member bends asymmetrically between the upper side and the lower side, and the bending width becomes wider on the lower side than on the upper side.

In one aspect of the present invention, the energy absorbing member is detachably attached to the front surface of the front bumper cross member.
In this way, even if the energy absorbing member is crushed due to a frontal collision of the vehicle, the energy absorbing member can be easily replaced.

  As described above, according to the present invention, when the vehicle collides frontward, the bending width is wider at the lower plate portion that is wider than the upper plate portion, and the bending width of the energy absorbing member is lower than the upper side. Become wider.

It is a perspective view showing the appearance of the vehicle which adopted the vehicle front part structure concerning the embodiment of the present invention. It is a perspective view showing composition of a vehicle front part structure concerning an embodiment of the present invention. It is sectional drawing which shows the structure of the vehicle front part structure shown in FIG. FIG. 3 is a perspective view showing a state where an energy absorbing member is removed from the vehicle front structure shown in FIG. 2. It is a disassembled perspective view of the energy absorption member shown in FIG. It is a figure for demonstrating the matter considered when determining the dimension of the upper side board part and lower side board part of the absorption side board shown in FIG. It is a schematic diagram for demonstrating the crushing process of the energy absorption member shown in FIG.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments suitable for a vehicle front structure according to the invention will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment, and all the structures demonstrated by this embodiment are not essential as a solution means of this invention.

  FIG. 1 is a perspective view showing the appearance of a vehicle that employs a vehicle front structure according to an embodiment of the present invention. FIG. 2 is a perspective view showing the configuration of the vehicle front structure according to the embodiment of the present invention, and FIG. 3 is a cross-sectional view showing the configuration of the vehicle front structure shown in FIG. 4 is a perspective view showing a state in which the energy absorbing member is removed from the vehicle front structure shown in FIG. 2, and FIG. 5 is an exploded perspective view of the energy absorbing member shown in FIG.

  As shown in FIG. 1, the vehicle front structure according to the embodiment of the present invention enables the front bumper (bumper facial 21) 2 and the body 3 to have a unity design. As shown in FIG. 2 and FIG. 3, the front bumper cross member 4 and the energy absorbing member 5 are provided.

  The front bumper cross member 4 is a vehicle body member constituting the front bumper 2 extending in the vehicle width direction at the front portion of the vehicle, and is a front end of a pair of left and right side members 61 and 62 provided along the vehicle traveling direction. Placed on the surface. The front bumper cross member 4 is fixed to the pair of left and right side members 61 and 62 by welding the entire circumference of the pair of left and right side members 61 and 62. The front bumper cross member 4 is parallel to the vehicle width direction between the pair of left and right side members 61 and 62 and is inclined rearward in the vehicle traveling direction on the outer side of the side members 61 and 62 in the vehicle width direction.

  As shown in FIG. 3, the front bumper cross member 4 is configured by combining a front member 41 disposed on the front side in the vehicle traveling direction and a rear member 42 disposed on the rear side in the vehicle traveling direction. It has a rectangular cross section with a short side and a long side in the vehicle vertical direction.

  The front member 41 is a steel plate having a uniform thickness formed into a groove shape. The front member 41 has a vehicle traveling direction front side along the vehicle vertical direction and a vehicle traveling direction rear side opened. The rear member 42 is formed by forming a steel plate having a uniform thickness into a slightly wider groove shape than the front member 41 so that the front member 41 is fitted. The rear side member 42 is open on the front side in the vehicle traveling direction, and the rear side in the vehicle traveling direction is along the vehicle vertical direction. The front member 41 is fitted into the opening of the rear member 42 and joined to the rear member 42 by welding or the like. The front member 41 and the rear member 42 can be made of any material and any thickness, but in this embodiment, they are formed of steel plates having the same material and the same thickness.

  As shown in FIGS. 3 and 4, the front bumper cross member 4 has a concave portion 41 a 1 in the center in the vehicle vertical direction on the front surface of the front member 41. The concave portion 41a1 is a portion that accommodates a first convex portion 51a1 and a second convex portion 51a2 provided on the fixed side plate 51 of the energy absorbing member 5, which will be described later, and is provided over the entire vehicle width direction. It is recessed toward the back in the direction of travel. The concave portion 41a1 has a width that allows the first convex portion 51a1 and the second convex portion 51a2 to fit in the vehicle vertical direction.

  Further, the front bumper cross member 4 has a plurality of female screw members 43 in the recess 41 a 1 of the front member 41. The plurality of female screw members 43 are screwed with bolts 53 for attaching the energy absorbing member 5 to the front bumper cross member 4, and in the concave portion 41 a 1 of the front side member 41 at the center in the vehicle vertical direction at a predetermined interval in the vehicle width direction. It is provided in the vicinity.

  As shown in FIG. 3, the female screw member 43 includes a plurality of through holes 41a2 and a plurality of nuts 43a. The plurality of through holes 41a2 are provided in the recess 41a1 of the front member 41 near the center in the vehicle vertical direction at predetermined intervals in the vehicle width direction, and the plurality of nuts 43a correspond to the plurality of through holes 41a2 on the back surface of the front member 41. It is provided in the position to do. The plurality of nuts 43a may be disposed only on the back surface of the front member 41, but in the present embodiment, they are joined to the back surface of the front member 41 by welding or the like from the viewpoint of improving work efficiency.

  Further, the front bumper cross member 4 has a plurality of through holes 42 a 1 in the rear member 42. The plurality of through holes 42a1 are for confirming whether or not the plurality of nuts 43a are welded to the back surface of the concave portion 41a1 of the front side member 41, and are disposed at positions where the plurality of female screw members 43 can be seen. Yes.

As shown in FIGS. 2 and 3, the energy absorbing member 5 is a pedestrian protection member having a polygonal closed cross-sectional shape that is crushed when the vehicle collides with the front, and is disposed on the front surface of the front bumper cross member 4 described above. It is attached with a bolt 53.
The energy absorbing member 5 is disposed along the front surface of the front bumper cross member 4 and has the same width as the front bumper cross member 4 in the vehicle width direction. Like the front bumper cross member 4, the energy absorbing member 5 is parallel to the vehicle width direction between the pair of left and right side members 61 and 62, and is inclined rearward in the vehicle traveling direction outside the side members 61 and 62. Yes.

  As shown in FIGS. 3 and 5, the polygonal closed cross-sectional shape of the energy absorption member 5 includes a fixed side plate 51 fixed to the front surface of the front bumper cross member 4 and a polygonal absorption side plate joined to the fixed side plate 51. 52.

  The fixed side plate 51 is formed by forming a steel plate having a uniform thickness into an L-shaped cross section, and includes a front plate portion 51a and a rear plate portion 51b. The fixed side plate 51 can be made of any material and any thickness, but in the present embodiment, a steel plate thinner than the thickness of the front bumper cross member 4 is adopted.

  As shown in FIG. 3, the front plate portion 51 a is a portion arranged along the front surface of the front bumper cross member 4, and has a slightly narrower width than the front bumper cross member 4 in the vehicle vertical direction. The rear plate portion 51b is a portion that extends rearward from the front plate portion 51a in a lower region of the front bumper cross member 4, and a connection plate portion 51c is formed between the front plate portion 51a and the rear plate portion 51b. . The connection plate portion 51c is disposed along the lower surface of the front bumper cross member 4, and the rear plate portion 51b extends obliquely downward from the connection plate portion 51c toward the rear of the vehicle. The rear plate portion 51b has a sufficient width to join a rear flange portion 52c of the absorption side plate 52 described later.

  As shown in FIG. 5, the energy absorbing member 5 has a first convex portion 51 a 1 near the center in the vehicle vertical direction in the front plate portion 51 a of the fixed side plate 51. The first convex portion 51a1 is a portion that fits into the concave portion 41a1 of the front member 41 of the front bumper cross member 4. The first convex portion 51a1 is provided over the entire vehicle width direction and protrudes toward the rear side in the vehicle traveling direction.

  The energy absorbing member 5 has a plurality of second convex portions 51 a 2 in the vehicle width direction in the first convex portion 51 a 1 of the front plate portion 51 a of the fixed side plate 51. As shown in FIG. 3, the plurality of second convex portions 51 a 2 is a portion in which a head 53 a of a bolt 53 for attaching the energy absorbing member 5 to the front bumper cross member 4 is accommodated, and on the front bumper cross member 4 side. Projecting from the mounting surface to the front bumper cross member 4 side than the height H1 of the head 53a of the bolt 53 (H1 <H2 in FIG. 3). The amount of protrusion of the plurality of second convex portions 51a2 is greater than the depth of the concave portion 41a1 included in the front member 41 of the front bumper cross member 4 described above, and is disposed in the concave portion 41a1 of the front member 41 of the front bumper cross member 4. It is provided at a position corresponding to the female screw member 43 and protrudes toward the rear side in the vehicle traveling direction with respect to the first convex portion 51a1 with a predetermined width L.

  As shown in FIG. 5, the energy absorbing member 5 has a plurality of through holes 51 a 3 in the front plate portion 51 a of the fixed side plate 51. The plurality of through holes 51a3 are for passing through the bolts 53 for attaching the energy absorbing member 5 to the front bumper cross member 4, and the female screw member 43 disposed in the recess 41a1 of the front member 41 of the front bumper cross member 4. , Specifically, at the center of the second convex portion 51a2 of the front plate portion 51a of the fixed side plate 51.

  The absorption side plate 52 is formed by forming a steel plate having a uniform thickness into a U-shaped cross section, and the polygonal closed cross-sectional shape of the energy absorbing member 5 formed on the front surface of the front bumper cross member 4 is a front side, a rear side. The front side of one side, the upper two sides, and the lower one side is a thin pentagon. The absorption side plate 52 has a pressure receiving plate portion 52a, a front flange portion 52b, and a rear flange portion 52c. The absorption side plate 52 can be made of any material and any thickness as long as it can be deformed relatively easily, but in this embodiment, a steel plate thinner than the thickness of the fixed side plate 51 is adopted.

  The pressure receiving plate portion 52 a is a portion that receives an impact when the vehicle collides with a pedestrian, and is disposed in parallel with the front plate portion 51 a of the fixed side plate 51. The front flange portion 52b is a portion that is joined to the upper front edge portion of the front plate portion 51a of the fixed side plate 51, and is provided in a belt shape along the vehicle width direction at the upper edge portion of the absorption side plate 52. The rear flange portion 52 c is a portion joined to the front surface of the rear plate portion 51 b of the fixed side plate 51, and is provided in a belt shape along the vehicle width direction at the lower edge portion of the absorption side plate 52.

  The absorption side plate 52 has an upper plate portion 52d between the pressure receiving plate portion 52a and the front flange portion 52b, and has a lower plate portion 52e between the pressure receiving plate portion 52a and the rear flange portion 52c. . Thus, in the absorption side plate 52, the lower plate portion 52e is wider than the upper plate portion 52d, and the length of the lower plate portion 52e is longer than the length 52d of the upper plate portion 52d.

  As shown in FIG. 3, the upper side plate portion 52d is a portion that connects the pressure receiving plate portion 52a and the front flange portion 52b. The upper plate portion 52d has a front end C at the boundary with the pressure receiving plate portion 52a and a connection point A with the front plate portion 51a at the boundary with the front flange portion 52b. Further, the upper side plate portion 52d is inclined so as to gradually increase from the pressure receiving plate portion 52a toward the front flange portion 52b. Further, the upper plate portion 52d has an inflection point (first ridgeline) 52d1 that forms a ridge line (first ridge line) 52d1 in the vehicle width direction slightly on the front flange portion 52b side between the pressure receiving plate portion 52a and the front flange portion 52b. Inflection point (B). The inflection point B is located above the straight line connecting the front end C of the upper plate portion 52d and the connection point A.

  The lower plate portion 52e is a portion that connects the pressure receiving plate portion 52a and the rear flange portion 52c. The lower plate portion 52e has a front end D at the boundary with the pressure receiving plate portion 52a and a connection point F with the rear plate portion 51b at the boundary with the rear flange portion 52c.

  The lower plate portion 52e is inclined so as to gradually become lower from the pressure receiving plate portion 52a toward the rear flange portion 52c. Further, the lower plate portion 52e has a ridge line (second line) in the vehicle width direction between the pressure receiving plate portion 52a and the rear flange portion 52c and in the vicinity of the ridge line in the vehicle vertical direction lower side on the front side in the vehicle traveling direction of the front bumper cross member 4. It has an inflection point (second inflection point) E that forms a (ridge line) 52e1. The inflection point E is located below the plane connecting the front end D of the lower plate portion 52e and the connection point F.

  As shown in FIGS. 3 to 5, the energy absorbing member 5 has a plurality of holes 52 a 1 in the pressure receiving plate portion 52 a of the absorption side plate 52. The plurality of holes 52 a 1 are tool holes for fastening the bolts 53 to the female screw member 43, and are arranged at positions corresponding to the through holes 51 a 3 provided in the front plate portion 51 a of the fixed side plate 51. The plurality of holes 52a1 are also used to adjust the deformation resistance of the energy absorbing member 5, that is, the energy that can be absorbed in an accident in which the vehicle collides with a pedestrian. For example, if the size of the plurality of holes 52a1 is increased, the deformation resistance of the energy absorbing member 5 is decreased, and if the size is decreased, the deformation resistance of the energy absorbing member 5 is increased. The hole 52a1 is provided in principle so as not to block the upper edge (ridge line) and the lower edge (ridge line). However, when it is desired to greatly reduce the deformation resistance of the energy absorbing member 5, either the upper edge or the lower edge is provided. You may provide so that either or both may be interrupted | blocked.

FIG. 6 is a diagram for explaining matters to be considered when determining the dimensions of the upper plate portion and the lower plate portion of the absorption side plate shown in FIG. 5. In FIG. 6, the lower limbs (legs) of the pedestrian are shown as a rectangular set.
As shown in FIG. 6, when the energy absorbing member 5 according to the present embodiment collides with a pedestrian and is crushed, the inflection point E that forms the ridge line 52 e 1 of the absorption side plate 52 is located at the lowermost position. Then, at the inflection point E forming the ridgeline 52e1, the speed becomes 0 km in the upper region, and it tries to move forward without being fully decelerated in the lower region. Thereby, a shearing force is generated at the inflection point E, but the shearing force depends on the weight of the lower region. Therefore, the lower the inflection point E is, the lower the weight of the lower region is, which is advantageous in reducing the pedestrian damage.

  For example, as shown to Fig.6 (a), the space | interval AB of the connection point A and the inflection point B with the front-surface board part 51a of the absorption side board 52, and the space | interval of the connection point A and the front end C of the upper side board part 52d. The distance DE between the front end D of the lower side plate portion 52e of the absorption side plate 52 and the inflection point E and the distance F between the inflection point E and the rear plate portion 51b with respect to the sum of AC (AB + AC). When the sum (DE + EF) with EF is small, the inflection point E is located at a high position, which is disadvantageous in reducing pedestrian damage.

  On the other hand, as shown in FIG. 6B, the distance AB between the connection point A and the inflection point B between the absorption side plate 52 and the front plate part 51a, and the distance between the connection point A and the front end C of the upper plate part 52d. The distance DE between the front end D of the lower side plate portion 52e of the absorption side plate 52 and the inflection point E and the distance F between the inflection point E and the rear plate portion 51b with respect to the sum of AC (AB + AC). When the sum of EF (DE + EF) is large, the inflection point E is located at a low position, which is advantageous in reducing pedestrian damage.

  Therefore, with respect to the sum (AB + AC) of the distance AB between the connection point A and the inflection point B of the absorption side plate 52 with the front plate part 51a and the distance AC between the connection point A and the front end C of the upper plate part 52d. The sum (DE + EF) of the distance DE between the front end D of the lower side plate portion 52e of the absorption side plate 52 and the inflection point E and the interval EF between the inflection point E and the connection point F between the rear plate portion 51b is set large. It is desirable to do.

FIG. 7 is a schematic diagram for explaining a crushing process of the energy absorbing member shown in FIG. 3.
As shown in FIG. 7A, in a state before the vehicle according to the present embodiment collides with a pedestrian or an obstacle, the energy absorbing member 5 is a polygon between the fixed side plate 51 and the absorption side plate 52. It has a closed cross-sectional shape.

  As shown in FIG. 7B, when the front portion of the vehicle according to the present embodiment collides with a pedestrian or an obstacle, the pressure receiving plate portion of the absorption side plate 52 of the energy absorbing member 5 as shown by an arrow in FIG. A force due to the collision is applied to 52a. The collision force acts toward the rear in the vehicle traveling direction, the upper plate 52d bends at the connection point A, the inflection point B, and the front end C, and the lower plate 52e has the connection point F, the inflection. Bend at three points, point E and front end D. The upper plate 52d is crushed while moving the inflection point B upward in the vehicle vertical direction, and the lower plate 52e is crushed while moving the inflection point E downward in the vehicle vertical direction. Thereby, the energy absorption member 5 absorbs the energy by collision.

  As shown in FIG. 7C, when a force due to a collision is further applied to the pressure receiving plate portion 52a of the absorption side plate 52 of the energy absorbing member 5, the upper plate portion 52d is completely crushed with the inflection point B as a boundary, The lower plate portion 52e is completely crushed with the inflection point E as a boundary. Thereby, the energy absorption member 5 absorbs the energy which can be absorbed. At this time, the head 53 a of the bolt 53 is sunk from the front surface of the front plate portion 51 a of the fixed side plate 51, so that it does not interfere with the absorption side plate 52 of the energy absorbing member 5.

  As described above, in the vehicle front structure according to this embodiment, the mounting surface of the energy absorbing member 5 on the front bumper cross member 4 side protrudes beyond the height of the head 53a of the bolt 53 on the front bumper cross member 4 side. And a second convex portion 51a2 that accommodates the head 53a of the bolt 53, and a concave portion 41a1 that is formed on the front side of the front bumper cross member 4 and accommodates the second convex portion 51a2. When the polygonal closed cross-sectional shape of the energy absorbing member 5 is crushed, the energy absorbing member 5 and the head 53a of the bolt 53 do not interfere with each other until the polygonal closed cross-sectional shape of the energy absorbing member 5 is completely crushed. Energy can be absorbed (see FIG. 7C).

  In addition, the energy absorbing member 5 is joined by combining a fixed side plate 51 disposed on the rear side in the vehicle traveling direction and an absorption side plate 52 disposed on the front side in the vehicle traveling direction, and between the fixed side plate 51 and the absorption side plate 52. Since the polygonal closed cross-sectional shape is formed, the fixed side plate 51 and the absorption side plate 52 can be made of an arbitrary material and an arbitrary thickness. Thereby, the load (deformation load) required for crushing the energy absorbing member 5 can be arbitrarily set.

  The polygonal closed cross-sectional shape of the energy absorbing member 5 includes a fixed side plate 51 fixed to the front side of the front bumper cross member 4 and a polygonal absorption side plate 52 joined to the fixed side plate 51. Therefore, the material and plate thickness of the fixed side plate 51 and the absorption side plate 52 can be made different. Thereby, the material and plate | board thickness of the absorption side plate 52 can be set arbitrarily, and the load (deformation load) required for crushing of the energy absorption member 5 can be set arbitrarily.

  The absorption side plate 52 has a pressure receiving plate portion 52a parallel to the front surface of the fixed side plate 51, and the pressure receiving plate portion 52a has a tool hole 52a1 for turning the bolt 53. It is easy and the energy absorbing member 5 can be easily fixed to the front bumper cross member 4.

Moreover, since the 2nd convex part 51a2 is provided in several places in the vehicle width direction, it is accommodated in the recessed part 41a1 in multiple places.
Further, since the energy absorbing member 5 is covered with the bumper facial 21, it is possible to design the bumper facial 21 and the body 3 with a sense of unity.

  Further, since the protruding amount of the second convex portion 51a2 is larger than the depth of the concave portion 41a1, a gap is opened between the energy absorbing member 5 and the front bumper cross member 4, and the energy absorbing member 5 and the front bumper cross are separated. It is possible to prevent raindrops that have entered between the members 4 from staying.

  The energy absorbing member 5 includes a front plate portion 51 a disposed along the front surface of the front bumper cross member 4, and a rear plate disposed extending rearward from the front plate portion 51 a in the lower region of the front bumper cross member 4. A fixed side plate 51 having a portion 51b, an upper plate portion 52d joined to the front plate portion 51a and extending forward, a lower plate portion 52e joined to the rear plate portion 51b and extending forward, and an upper plate portion 52d. An absorption side plate 52 having a pressure receiving plate portion 52a disposed in parallel with the front plate portion 51a between the front end and the front end of the lower plate portion 52e. Therefore, the absorption side plate 52 is lower than the upper plate portion 52d. The side plate portion 52e is wider. As a result, when the vehicle collides with the front, the bending width of the lower plate portion 52e, which is wider than the upper plate portion 52d, becomes wider, and the bending width of the energy absorbing member 5 becomes wider than the upper side.

  The upper plate portion 52d has an inflection point B that forms a ridge line 52d1 in the vehicle width direction, and the lower plate portion 52e has an inflection point E that forms a ridge line 52e1 in the vehicle width direction. Since the position of the inflection point E is arranged behind the position of the inflection point B, when the vehicle collides with the front, the upper plate part 52d bends at the inflection point B forming the ridgeline 52d1, and the lower plate part 52e It bends at an inflection point E that forms a ridge line 52e1 arranged behind the inflection point B. Thereby, when the vehicle collides with the front, the bending width of the energy absorbing member 5 is wider on the lower side than on the upper side.

  Further, the inflection point B is located above a straight line connecting the connection point between the front end of the upper plate portion 52d and the front plate portion 51a of the upper plate portion 52d, and the inflection point E is the lower plate portion 52e. Since it is located below the straight line connecting the connection point between the front end and the rear plate portion 51b of the lower plate portion 52e, the upper plate portion 52d has an inflection point B that forms the ridgeline 52d1 when the vehicle collides with the front. The lower plate portion 52e is bent so as to protrude downward at the inflection point E forming the ridge line 52e1. Thereby, when the vehicle collides with the front, the absorption side plate 52 is reliably bent, and the energy absorbing member 5 is crushed as set.

  In addition, since the length of the lower plate portion 52e is longer than the length of the upper plate portion 52d, when the vehicle collides with the front, it first bends at the upper plate portion 52d and then bends at the lower plate portion 52e. The bending width of the lower plate portion 52e is wider than the bending width of the energy absorbing member 5, and the bending width of the energy absorbing member 5 is wider on the lower side than the upper side.

  Further, the polygonal closed cross-sectional shape of the energy absorbing member 5 formed on the front surface of the front bumper cross member 4 is a pentagonal shape in which the front side, the rear side, the upper two sides, and the lower side piece are narrow in front. When the frontal collision occurs, the energy absorbing member 5 bends asymmetrically between the upper side and the lower side, and the bending width becomes wider on the lower side than the upper side.

  Further, since the energy absorbing member 5 is detachably attached to the front surface of the front bumper cross member 4, the energy absorbing member 5 can be easily replaced even if the energy absorbing member 5 is crushed due to a frontal collision of the vehicle.

  As described above, since the bending width of the energy absorbing member is wider on the lower side than on the upper side, the present invention is suitable for reducing pedestrian damage in an accident in which an automobile collides with a pedestrian.

2 Front bumper 21 Bumper facial 3 Body 4 Front bumper cross member 41 Front member 41a1 Recess 41a2 Through hole 42 Rear member 42a1 Through hole 43 Female thread portion 43a Nut 5 Energy absorbing member 51 Fixed side plate 51a Front plate portion 51a1 First convex Part 51a2 Second convex part 51a3 Through hole 51b Rear plate part 51c Connection plate part 52 Absorption side plate 52a Pressure receiving plate part 52a1 Hole 52b Front flange part 52c Rear flange part 52d Upper plate part 52d1 Ridge line (first ridge line)
52e Lower plate part 52e1 Ridge line (second ridge line)
53 Bolt 53a Head 61, 62 Side member

Claims (6)

A front bumper cross member constituting a front bumper extending in the vehicle width direction at the front of the vehicle;
An energy absorbing member fixed to the front surface of the front bumper cross member and having a polygonal closed cross-sectional shape that is crushed when the vehicle collides front;
With
The energy absorbing member is
A fixed side plate having a front plate portion arranged along the front surface of the front bumper cross member, and a rear plate portion arranged to extend rearward from the front plate portion in a lower region of the front bumper cross member;
The front plate portion is joined to the front plate portion and extends forward, the lower plate portion is joined to the rear plate portion and extends forward, and the front plate is located between the front end of the upper plate portion and the front end of the lower plate portion. An absorption side plate having a pressure receiving plate portion disposed in parallel with the face plate portion,
The vehicle front part structure characterized by including.   A first inflection point that forms a first ridge line in the vehicle width direction on the upper plate portion, and a second inflection point that forms a second ridge line in the vehicle width direction on the lower plate portion. The vehicle front part structure according to claim 1, wherein the position of the second inflection point is arranged behind the position of the first inflection point. The first inflection point is located above a straight line connecting a connection point between the front end of the upper plate portion and the front plate portion of the upper plate portion,
The second inflection point is located below a straight line connecting a connection point between a front end of the lower plate portion and the front plate portion of the lower plate portion. Vehicle front structure.   The length of the said lower side board part is longer than the length of the said upper side board part, The vehicle front part structure as described in any one of Claims 1-3 characterized by the above-mentioned.   The polygonal closed cross-sectional shape of the energy absorbing member formed on the front surface of the front bumper cross member is a pentagonal shape in which the front side, the rear side, the upper side and the lower side piece are narrow in front. The vehicle front part structure as described in any one of Claims 1-4.   The vehicle front structure according to claim 1, wherein the energy absorbing member is detachably attached to a front surface of the front bumper cross member.

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