JP2019172117A - Vehicle front part structure - Google Patents

Abstract

To provide a vehicle front part structure which enables reduction of an injury value against a pedestrian.SOLUTION: A vehicle front part structure 1 includes: a front bumper 5 provided at a front end of a vehicle; a frame-like member 2 which is located behind the front bumper 5 and to which a cooling device of an engine is attached; and a lower load support member 3 which has a hollow shape opening at the vehicle rear side, is attached to a front end of a lower piece 2D of the frame-like member 2, and extends to the rear side of the front bumper 5. The lower load support member 3 extends in a vehicle width direction and includes a polygonal line part 39 which is a base point of bending of the lower load support member 3 to the vehicle lower side.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a vehicle front structure including a frame-like member to which an engine cooling device is attached behind a front bumper.

  A front bumper, which is an exterior member, is attached to the front end of the vehicle. The vehicle employs a configuration in which when a pedestrian or the like collides with the front bumper, the impact is absorbed to reduce the obstacle value for the pedestrian and to protect the vehicle occupant. For example, in the vehicle of Patent Document 1, an energy absorbing member is arranged on the back side of the front bumper, or a lower leg support member (lower load support member) is arranged to reduce an obstacle value for a pedestrian. The lower leg support member is considered to be a foot-wiping member that reduces the obstacle value to the pedestrian by jumping up the lower part from the pedestrian's knee and riding the pedestrian on the hood.

Japanese Patent No. 3740901

  In recent years, from the viewpoint of pedestrian protection, it has been required to further reduce the obstacle value for pedestrians. For example, with respect to the lower load support member, depending on how the pedestrian collides with the vehicle, the pedestrian's lower knee portion may enter the lower side of the lower load support member. In particular, height wagons and SUVs with high vehicle height have increased in recent years, and the lower knee part tends to enter the lower side of the lower load support member. If it becomes so, a big load will be applied to a knee joint of a pedestrian and there exists a possibility that the obstacle value with respect to a pedestrian may become high.

  One of the objects of the present invention is to provide a vehicle front structure that can reduce an injury value for a pedestrian.

A vehicle front structure according to an aspect of the present invention is
A vehicle front structure comprising a front bumper provided at a front end of a vehicle and a frame-like member to which an engine cooling device is attached behind the front bumper,
A hollow shape with an open rear side of the vehicle, and a lower load support member attached to a front end of a lower piece of the frame-like member and extending toward the back side of the front bumper;
The lower load support member includes a broken line portion that extends in the width direction of the vehicle and serves as a bending base point of the lower load support member toward the lower side of the vehicle.

  In the above configuration, the lower load support member is provided with a broken line portion, and when an impact is applied to the lower load support member from the front side of the vehicle, the lower load support member is bent to the lower side of the vehicle. In other words, when the pedestrian collides with the front bumper, the lower load support member bends in the downward direction away from the knee joint, so that the lower part of the pedestrian's knee does not easily enter the lower side of the lower load support member, and the knee joint becomes large. It can suppress that force acts.

FIG. 2 is a schematic front view of the vehicle with the front bumper shown in the first embodiment removed. FIG. 2 is a schematic view of an attachment state of the lower load support member shown in Embodiment 1 as seen from the front and slightly above the vehicle. It is the schematic which looked at the attachment state of the lower load support member shown in Embodiment 1 from the downward direction of the vehicle. It is IV-IV sectional drawing of FIG. It is VV sectional drawing of FIG. It is explanatory drawing explaining a deformation | transformation state when stress acts on the lower load support member shown in Embodiment 1 from the front of a vehicle.

  A vehicle front structure 1 according to an embodiment of the present invention will be described with reference to FIGS. The same reference numerals in the figure indicate the same names. In the figure, “FR” indicates the front of the vehicle, “RR” indicates the rear of the vehicle, “UP” indicates the upper side of the vehicle, “LWR” indicates the lower side of the vehicle, “LH” indicates the left side of the vehicle, and “RH” indicates the right side of the vehicle. Show. In addition, this invention is not limited to these illustrations, is shown by the claim, and it is intended that all the changes within the meaning and range equivalent to a claim are included.

<Embodiment 1>
≪Overall structure≫
FIG. 1 shows the vicinity of the front end of a monocoque body of a vehicle. The vehicle front structure 1 shown in FIG. 1 includes a frame-like member 2 that holds a radiator (cooling device) that cools the engine. The frame-like member 2 is a member also called a radiator support, and is a rectangular frame-like metal member having an upper piece 2U, a lower piece 2D, a left piece 2L, and a right piece 2R as shown in FIG. An ODB (Offset Deformable Barrier) member 4 is disposed further forward of the frame-like member 2 in the vehicle. The ODB member 4 is a metal member that is connected to an intermediate portion of the left piece 2L in the vehicle height direction and an intermediate portion of the right piece 2R in the vehicle height direction. In this example, a vertical piece 40 for connecting the frame-like member 2 and the ODB member 4 is further provided. The vertical piece 40 connects the intermediate portion of the upper piece 2U in the vehicle width direction and the intermediate portion of the ODB member 4 in the vehicle width direction. As one of the features of the vehicle front structure 1 of the present example having the above-described configuration, a configuration of the lower load support member 3 attached to the lower piece 2D of the frame-like member 2 can be exemplified.

  Hereinafter, the configuration of the lower piece 2D will be described with reference to FIGS. 2 to 5 in addition to FIG. 1, and then the configuration of the lower load support member 3 will be described. FIG. 2 is a view of the assembly of the lower piece 2D of the frame-like member 2 and the lower load support member 3 attached to the lower piece 2D, as viewed obliquely from above the vehicle, and FIG. 4 is a part of the assembly. It is a longitudinal cross-sectional view. 3 is a view of the assembly of the lower piece 2D and the lower load support member 3 as viewed from below the vehicle, and FIG. 5 is a partial cross-sectional view of the assembly.

≪Bottom piece of frame-like member≫
The lower piece 2D of this example is longer in the vehicle width direction than the upper piece 2U of the frame-shaped member 2 as shown in FIG. As shown in FIG. 4, the lower piece 2 </ b> D of this example is configured by combining a lower piece lower material 20 disposed below the vehicle and a lower piece upper material 21 disposed above the vehicle on the lower piece lower material 20. Is done. The lower piece lower member 20 and the lower piece upper member 21 are joined at the vehicle front side and the vehicle rear side, and the lower piece 2D is hollow.

  Of the lower piece lower member 20, a plurality of convex portions 23 projecting upward of the vehicle are provided at the front end of the vehicle, which is overlapped with the lower piece upper member 21, as shown in FIGS. More specifically, as shown in the cross-sectional view of FIG. 5, the convex portion 23 includes a flat top portion 23t and a pair of outer wall portions 23w that are inclined toward the top portion 23t. The distance between both outer wall portions 23w gradually decreases toward the top portion 23t.

  As shown in FIG. 3, the convex portions 23 are provided separately in the vehicle width direction of the lower piece lower member 20. As shown in FIG. 5, the top portion 23 t of the convex portion 23 is a portion that comes into contact with the lower surface of the lower piece upper member 21 that is flat and serves as a joint location to the lower piece upper member 21. The number and arrangement of the protrusions 23 are not particularly limited, but the number and arrangement of the protrusions 23 may be determined so that the bonding strength between the lower piece lower member 20 and the lower piece upper member 21 can be secured. In this example, as shown in FIG. 3, three convex portions 23 are formed in the middle portion of the lower piece lower member 20 in the vehicle width direction, and five portions are provided on each of the left and right portions in the vehicle width direction. The convex part 23 is formed. Since the plurality of protrusions 23 are distributed in the vehicle width direction of the lower piece lower member 20, the bonding strength between the lower piece lower member 20 and the lower piece upper member 21 is uniform over the entire length of the lower piece 2D in the vehicle width direction. It has become.

  In addition, as shown in FIG. 2, on the upper surface of the lower piece upper member 21, a pair of attachment portions 25 for attaching the lower piece 2D to the left piece 2L and the right piece 2R of FIG. As shown in FIG. 3, the lower piece lower member 20 is formed with a plurality of through windows 2w. The through window 2w normally has a function of reducing the weight of the lower piece 2D and discharging the environmental water that has entered the lower piece 2D. However, when the load is input, the separation space of the through window exhibits a function of absorbing an impact. .

[Lower load support member]
As shown in FIG. 4, the lower load support member 3 is configured by combining a support lower member 30 disposed below the vehicle and a support upper member 31 disposed above the support lower member 30. The support lower member 30 and the support upper member 31 are connected at the front of the vehicle, but are separated from each other at the rear of the vehicle. Therefore, the lower load support member 3 has a hollow shape with an opening at the rear of the vehicle. The lower load support member 3 extends toward the back side of the front bumper 5. The tip of the lower load support member 3 may not be connected to the front bumper 5 or may be connected. If the lower load supporting member 3 and the front bumper 5 are separated from each other, the separated space also contributes to the impact absorption.

  The vehicle rear side of the support lower member 30 is fixed to the upper surface of a portion of the lower piece upper member 21 that overlaps the lower piece lower member 20. On the other hand, the vehicle rear side of the support upper material 31 is fixed to the upper surface of a portion of the lower piece upper material 21 that is separated from the lower piece lower material 20 to the upper side of the vehicle. The support upper material 31 is lowered to the vehicle lower side toward the vehicle front, and the lower load support member 3 is gradually thinned toward the vehicle front.

  As shown in FIG. 3, a concave portion 33 is formed in a position corresponding to the convex portion 23 of the lower piece lower material 20 in the support lower material 30. As shown in the cross-sectional view of FIG. 5, the recess 33 is recessed below the vehicle. More specifically, the recessed part 33 is comprised by the flat bottom part 33b and a pair of inner wall part 33w which inclines toward this bottom part 33b. The distance between both inner wall portions 33w gradually decreases toward the bottom portion 33b.

  As shown in FIG. 5, the lower surface of the bottom 33 b of the recess 33 is in contact with the lower piece upper material 21 and serves as a joint location to the lower piece upper material 21 (see also FIG. 4). The three of the concave portion 33 of the lower load supporting member 3, the lower piece upper member 21, and the convex portion 23 of the lower piece lower member 20 are connected by spot welding or the like. When spot welding is performed, at least two of the three overlapping portions are spot welded. The two spot weldings are preferably shifted at least in the vehicle front-rear direction.

  By setting the lower load supporting member 3 to be attached to the lower piece 2D as described above, as shown in FIG. 4, the lower load supporting member 3 includes a base point for bending the lower load supporting member 3 downward in the vehicle. A broken line portion 39 is formed. The broken line portion 39 is formed at a boundary line between a portion supported by the lower piece 2D and a portion not supported by the lower piece 2D. In this example, as described with reference to FIG. 5, the lower load support member 3 is in contact with the lower piece upper member 21 only at the position of the recess 33. Therefore, the broken line portion 39 of this example is intermittently formed in the vehicle width direction as shown in FIG.

≪Effect≫
According to the vehicle front structure 1 described above, an injury value for a pedestrian who collides with the front bumper 5, particularly an injury value for a knee joint, can be reduced. This is because, as shown in FIG. 6, when a stress is applied from the front of the vehicle as indicated by the white arrow, the front portion of the lower load support member 3 is bent downward from the lower portion of the vehicle with the broken line portion 39 as a base point. . The lower load support member 3 bends downward in the vehicle because the rear portion of the lower load support member 3 with respect to the broken line portion 39 is supported by the lower piece 2D and is highly rigid, and therefore the stress in the front of the vehicle is broken. This is because the vehicle heads downward from the portion 39 as a base point. Further, the inclination of the support upper member 31 of the lower load support member 3 so as to be lowered downward as the vehicle moves forward is also a factor that the lower load support member 3 is easily bent downward of the vehicle. Usually, the position of the impact of the pedestrian is higher in the vehicle than the joint between the lower load support member 3 and the front bumper 5 (FIG. 4). Works. As a result, it is considered that the lower load support member 3 bends downward in the vehicle because a force that crushes the lower load support member 3 obliquely from the front upper side of the vehicle acts.

<Embodiment 2>
The configuration of the broken line portion is not limited to the configuration of the first embodiment. For example, the broken line portion can be formed by a groove formed in the lower load support member 3. The groove is preferably formed so as to extend in the vehicle width direction. The groove may be provided in either the support lower member 30 or the support upper member 31, but both ends of the groove are formed in the entire length in the width direction of the lower load support member 3 so that the rigidity of the lower load support member 3 does not decrease. It is preferable not to reach. For example, forming a plurality of grooves formed intermittently in the vehicle width direction can be mentioned. In this case, if the grooves are arranged in a straight line, the lower load support member 3 is easily bent downward when the impact is applied.

DESCRIPTION OF SYMBOLS 1 Vehicle front part structure 2 Frame-shaped member 2D Lower piece 2L Left piece 2R Right piece 2U Upper piece 2w Through-hole window 20 Lower piece lower material 21 Lower piece upper material 23 Convex part 25 Mounting part 23t Top part 23w Outer wall part 3 Lower load support member 30 Support Lower Material 31 Support Upper Material 33 Concave portion 39 Polygonal Line Part 33b Bottom Part 32w Inner Wall Part 4 ODB Member 40 Vertical Piece 5 Front Bumper

Claims (1)

A vehicle front structure comprising a front bumper provided at a front end of a vehicle and a frame-like member to which an engine cooling device is attached behind the front bumper,
A hollow shape with an open rear side of the vehicle, and a lower load support member attached to a front end of a lower piece of the frame-like member and extending toward the back side of the front bumper;
The lower load support member extends in the width direction of the vehicle, and has a vehicle front structure including a broken line portion serving as a base point for bending the lower load support member to the lower side of the vehicle.

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