Bumper reinforcement

Abstract

The present invention relates to a bumper reinforcement. The bumper (RF) comprises a front wall (12), a rear wall (14) located rearward of the front wall (12), one or more transverse walls (16) connecting the front wall (12) and the rear wall (14), and a notch (22) extending inward in the vehicle width direction from a vehicle width direction end of the transverse wall (16). The region of the vehicle width direction end of the bumper (RF) is divided into a front end (24) located forward of the notch (22) and a rear end (26) located rearward of the notch (22). The front end (24) is bent rearward in an inclined manner relative to the rear wall (14) and has a protrusion (28) protruding outward in the vehicle width direction from a vehicle width direction end of the rear end (26).

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of Japanese Patent Application No. 2021-016708, filed on February 4, 2021, the entire contents of which including the specification, claims, drawings, and abstract are incorporated herein by reference. Technical Field

[0003] This specification discloses a bumper reinforcement extending in the vehicle width direction at the front portion of a vehicle. Background Art

[0004] A bumper reinforcement (hereinafter referred to as "bumper RF") extending in the vehicle width direction is provided at the front portion of the vehicle in order to improve impact resistance. Various structures have been proposed for the bumper RF.

[0005] For example, Patent Document 1 discloses a bumper RF having a front wall, a rear wall, and a transverse wall connecting the front and rear walls. In Patent Document 1, a notch extending in the vehicle width direction is formed in the transverse wall at the vehicle width end of the bumper RF. This notch divides the vehicle width end of the bumper RF into a front portion and a rear portion. Furthermore, the front portion is bent toward the rear wall.

[0006] Patent Document 2 discloses a bumper RF made of a hollow extrusion (referred to as a "bumper beam" in Patent Document 2). In Patent Document 2, the rear corner of the end portion of the bumper RF in the vehicle width direction is notched into a substantially rectangular shape, and the portion forward of the notch is formed into a protrusion that protrudes outward in the vehicle width direction.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2019-006168

[0010] Patent Document 2: Japanese Patent Application Laid-Open No. 2015-058759

[0011] However, in such a conventional bumper RF, when an obstacle collides with the vehicle width direction end portion of the bumper RF from the front, the forward convex corner may be strongly sunk into the obstacle.

[0012] For example, in Patent Document 1, the rear end in the vehicle width direction protrudes outward relative to the front end in the vehicle width direction. Therefore, in Patent Document 1, both the front corner of the front portion and the rear corner of the rear portion are exposed forward, and these two corners may be trapped by obstacles.

[0013] Furthermore, in Patent Document 2, when an obstacle collides with the vehicle widthwise end of the bumper RF, the protrusion sharply bends rearward at its base, resulting in a forward convex corner at the base of the protrusion, which may sink into the obstacle.

[0014] Therefore, this specification discloses a bumper RF that can effectively prevent the vehicle width direction end portion of the bumper RF from being strongly sunk into the obstacle when the obstacle collides with the vehicle width direction end portion of the bumper RF from the front. Summary of the Invention

[0015] The bumper RF disclosed in this specification is characterized in that it includes a front wall, a rear wall located rearward of the front wall, one or more transverse walls connecting the front wall and the rear wall, and a cutout extending inward in the vehicle width direction from the vehicle width direction end of the transverse wall, the area of ​​the vehicle width direction end of the bumper reinforcement is divided into a front side end located forward of the cutout and a rear side end located rearward of the cutout, the front side end is bent rearward in an inclined manner relative to the rear wall, and has a protrusion protruding outward in the vehicle width direction from the vehicle width direction end of the rear side end.

[0016] Because the front end has a protrusion that projects outward in the vehicle width direction from the rear end's distal end, the front corner of the rear end is covered and concealed by the front end. Furthermore, when an obstacle collides from the front, the protrusion bends rearward, causing the front corner of the front end to face rearward. As a result, the absence of a forward-facing convex corner during an obstacle collision effectively prevents the vehicle width end of the bumper RF from violently digging into the obstacle.

[0017] In this case, the amount of protrusion of the protrusion from the rear end portion may be smaller than a dimension of the protrusion in a thickness direction.

[0018] By setting it as this structure, the protrusion is not easy to bend, so when an obstacle hits from the front, the protrusion bends gently. As a result, it is possible to prevent the bent portion of the protrusion from sinking into the obstacle.

[0019] Furthermore, before the front end portion is bent rearward, the front edge of the cutout is substantially parallel to the front wall, and the rear edge of the cutout is inclined relative to the rear wall so as to approach the rear wall as it approaches the end in the vehicle width direction.

[0020] By setting this structure, the longitudinal dimension (and thus the strength) of the area of ​​the vehicle width end of the bumper RF can be gradually reduced as it approaches the vehicle width outer side. As a result, local concentration of stress can be suppressed, thereby effectively preventing the protrusion from being sharply bent or broken.

[0021] Effects of the Invention

[0022] According to the technology disclosed in this specification, it is possible to effectively prevent the vehicle width direction end portion of the bumper RF from being strongly sunk into an obstacle. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic plan view of a vehicle to which the bumper RF is applied.

[0024] Figure 2 It is a perspective view of the bumper RF.

[0025] Figure 3 yes Figure 1 AA cross-sectional view.

[0026] Figure 4 is a top view of the end region.

[0027] Figure 5 It is a plan view of the end region of the bumper RF during manufacture.

[0028] Figure 6 It is a top view of the end area when the obstacle hits.

[0029] Figure 7 It is a plan view of a vehicle width direction end portion of the bumper RF according to the first comparative example.

[0030] Figure 8 It is a plan view of a vehicle width direction end portion of the bumper RF according to the second comparative example.

[0031] Figure 9 1 is a plan view of the vehicle width direction end portion of the bumper RF of the second comparative example when colliding with an obstacle.

[0032] Description of labels

[0033] 10 bumper RF, 12 front wall, 14 rear wall, 16 transverse wall, 20 end area, 22 cutout, 24 front end, 26 rear end, 28, 50 protrusions, R bent portion, Sm longitudinal beam, V vehicle. DETAILED DESCRIPTION

[0034] Hereinafter, the structure of the bumper RF10 will be described with reference to the drawings. Figure 1 : is a schematic top view of a vehicle V to which the bumper RF10 is applied. Figure 2 This is a three-dimensional image of the bumper RF10. Figure 3 yes Figure 1 It should be noted that in each figure, "Fr", "Up" and "Rh" represent the front of the vehicle, the top of the vehicle and the right side of the vehicle, respectively.

[0035] like Figure 1 As shown, the vehicle V includes a pair of left and right longitudinal members Sm and a bumper RF10. The longitudinal members Sm are skeletal members that are elongated in the vehicle's longitudinal direction. The pair of longitudinal members Sm are spaced apart in the vehicle width direction. The bumper RF10 is a skeletal member that is elongated in the vehicle width direction and is positioned at the front of the vehicle V. The front ends of the pair of longitudinal members Sm are connected to the bumper RF10.

[0036] The bumper RF10 is formed into a square tube shape extending horizontally from one end (right end) to the other end (left end) in the vehicle width direction of the vehicle V. Specifically, Figure 3 As shown, the bumper RF10 includes a front wall 12, a rear wall 14 located further rearward than the front wall 12, and a plurality of transverse walls 16 connecting the front wall 12 and the rear wall 14. The front wall 12 and the rear wall 14 are each formed into a strip extending in the vehicle width direction. The wall surface of the front wall 12 (i.e., the surface perpendicular to the thickness direction) faces forward. The rear wall 14 is arranged behind the front wall 12, with the wall surface of the rear wall 14 facing rearward. The transverse wall 16 is formed into a strip extending in the vehicle width direction between the front wall 12 and the rear wall 14. In this example, a plurality of transverse walls 16 are provided, arranged in the vertical direction. One of the plurality of transverse walls 16 connects the upper edge of the front wall 12 and the upper edge of the rear wall 14, another one of the plurality of transverse walls 16 connects the lower edge of the front wall 12 and the lower edge of the rear wall 14, and the remaining plurality of transverse walls 16 connect the middle of the front wall 12 in the height direction and the middle of the rear wall 14 in the height direction.

[0037] When mounted on a vehicle V, the bumper RF10 is designed to conform to the front end of the vehicle V. Specifically, the bumper RF10 is curved in a generally arcuate shape when viewed from above, with both ends of the bumper RF10 located further rearward of the vehicle than the center. In particular, at the vehicle widthwise ends of the bumper RF10, the front wall 12 is inclined relative to the rear wall 14, approaching the rear wall 14 as it moves outward in the vehicle widthwise direction. Hereinafter, this region where the front wall 12 is inclined relative to the rear wall 14 is referred to as the "end region 20."

[0038] Figure 4 is a top view of the end region 20, Figure 5 FIG. 2 is a top view of the end region 20 of the bumper RF10 during manufacture. Figure 4 、 Figure 5 As shown, in the end region 20, a notch 22 is formed in the transverse wall 16, extending inward in the vehicle width direction from the distal end thereof. The end region 20 is divided into a front end 24 located forward of the notch 22 and a rear end 26 located rearward of the notch 22. The front end 24 is bent rearward to fill the notch 22 and contact the rear end 26.

[0039] Here, if Figure 5As shown, before the front end portion 24 is bent, the cutout 22 is in a gradually expanding shape with its front-to-rear dimension increasing as it approaches the end in the vehicle width direction. More specifically, the front edge of the cutout 22 is substantially parallel to the front wall 12, and the rear edge of the cutout 22 is inclined relative to the rear wall 14 so as to approach the rear wall 14 as it approaches the end in the vehicle width direction. In this example, the front end portion 24 is bent so as to fill the cutout 22. Thus, as shown in FIG. Figure 4 As shown, in the completed state, the front end portion 24 is inclined so as to approach the rear wall 14 as it approaches the end in the vehicle width direction. In addition, the longitudinal dimension of the end portion region 20 gradually decreases as it approaches the end in the vehicle width direction.

[0040] In addition, if Figure 5 As shown, the end of the rear end portion 26 in the vehicle width direction is cut off, and the end of the rear end portion 26 in the vehicle width direction is located further inward in the vehicle width direction than the end of the front end portion 24 in the vehicle width direction. Figure 4 As shown, the vehicle width end of the front end portion 24 protrudes outward in the vehicle width direction more than the vehicle width end of the rear end portion 26. Hereinafter, the portion of the front end portion 24 that protrudes outward in the vehicle width direction more than the rear end portion 26 is referred to as the "protrusion 28". By providing the protrusion 28, when viewed from the front of the vehicle, the front corner Cr of the rear end portion 26 is covered and hidden by the front end portion 24. It should be noted that the protrusion amount L1 of the protrusion 28 is smaller than the thickness direction dimension (i.e., the dimension in the direction orthogonal to the protrusion direction) L2 of the protrusion 28. By setting it to this dimension, the protrusion 28 can be prevented from bending steeply in the event of a frontal collision, but this will be described later.

[0041] Such a bumper RF10 is obtained by processing a square tube member having a front wall 12, a rear wall 14 and a plurality of transverse walls 16. The square tube member that forms the material of the bumper RF10 is manufactured, for example, by extruding an aluminum alloy material. In this case, the extrusion direction of the aluminum alloy material coincides with the vehicle width direction. When manufacturing the bumper RF10, the square tube member is bent so as to be roughly bow-shaped when viewed from above. In addition, in the vehicle width direction end of the bumper RF10, that is, in the end area 20, a portion of the transverse wall 16 and the rear wall 14 is trimmed to form a cutout 22. Then, if the front end 24 located in front of the cutout 22 is bent rearward so that the front end 24 contacts the rear end 26, the bumper RF10 is completed.

[0042] As is apparent from the description so far, in this example, the front end portion 24 is made to protrude outward in the vehicle width direction relative to the vehicle width direction end of the rear end portion 26. The reason for this configuration will be described in comparison with a comparative example. Figure 7This is a top view of the vehicle width end of the bumper RF10 of the first comparative example. The bumper RF10 of the first comparative example is disclosed in Patent Document 1. In the first comparative example, the bumper RF10 also has a front wall 12, a wall 14, and a plurality of transverse walls 16. Furthermore, a notch 22 is formed at the vehicle width end of the bumper RF10, dividing the vehicle width end into a front end 24 and a rear end 26. However, in the first comparative example, the vehicle width end of the front end 24 is located further inboard of the vehicle width end of the rear end 26. Therefore, in the first comparative example, both the front corner Cf of the front end 24 and the front corner Cr of the rear end 26 are exposed toward the front of the vehicle. In this first comparative example, if an obstacle collides with the vehicle width end of the bumper RF10 from the front, the front corners Cf and Cr, which protrude forward, may be violently pressed into the obstacle.

[0043] On the other hand, in this example, the front corner Cr of the rear end portion 26 is covered and concealed by the front end portion 24, preventing it from being trapped by obstacles. Furthermore, the front end portion 24 includes a protrusion 28 that projects outward in the vehicle width direction relative to the rear end portion 26. This protrusion 28, when subjected to a rearward load, readily deforms in a direction that avoids the load. Therefore, if an obstacle collides with the end region 20 of the bumper RF10 from the front, the protrusion 28 bends rearward from its base, deforming. Figure 6 is a top view of the end region 20 when the obstacle collides. Figure 6 In FIG, the double-dashed line represents the shape of the end region 20 before deformation. Figure 6 As shown, if the protrusion 28 is bent, the front corner Cf of the front end portion 24 does not sink into obstacles and instead faces the rear of the vehicle. Furthermore, the protrusion L1 of the protrusion 28 is smaller than the thickness dimension L2. Consequently, the protrusion 28 is less likely to bend sharply, and the bend R formed at the base of the protrusion 28 tends to form a gently curved surface. As a result, the bend R is prevented from violently sinking into obstacles. In other words, according to this example, compared to the first comparative example, the vehicle width end portion of the bumper RF10 can be effectively prevented from violently sinking into obstacles.

[0044] Figure 8 The figure is a top view of the vehicle width end portion of the bumper RF10 of the second comparative example. The bumper RF10 of the second comparative example is disclosed in Patent Document 2. In the second comparative example, the bumper RF10 also has a front wall 12, a rear wall 14, and a plurality of transverse walls 16. In the second comparative example, the rear corners of the vehicle width end portion of the square cylindrical member are trimmed into a roughly rectangular shape, and the portion forward of the trimmed portion is formed into a protrusion 50 that protrudes outward in the vehicle width direction. The protrusion 50 curves gently as it approaches the rear as it moves outward in the vehicle width direction.

[0045] In this second comparative example, since the front corner Cf of the protrusion 50 is not facing forward, even if an obstacle collides with it, the front corner Cf is prevented from digging into the obstacle. However, in the second comparative example, the protrusion 50's protrusion amount L1 is significantly greater than the thickness dimension L2. Furthermore, in the second comparative example, the strength of the bumper RF10 changes dramatically at the base of the protrusion 50. Consequently, in the second comparative example, stress tends to concentrate at the base of the protrusion 50. As a result, the protrusion 50 may bend sharply or break at its base if an obstacle collides with it. Figure 9 FIG. 2 shows the deformation of the bumper RF10 of the second comparative example when colliding with an obstacle. Figure 9 As shown, in the second comparative example, when an obstacle collides, an angular bent portion R is formed, which may violently sink into the obstacle.

[0046] On the other hand, in this example, as described above, the protrusion 28 has a protrusion amount L1 smaller than the thickness dimension L2, so the protrusion 28 bends gently. Therefore, in this example, the bent portion R has no sharp corners, which can prevent the bent portion R from suddenly sinking into an obstacle.

[0047] Furthermore, in this example, a portion of the transverse wall 16 is cut away in the end region 20, causing the front-to-rear dimension of the rear end 26 to gradually decrease as it approaches the outer side in the vehicle width direction. In other words, in this example, the strength of the bumper RF10 gradually decreases as it approaches the end in the vehicle width direction. Consequently, in this example, stress is easily dispersed. As a result, when an obstacle collides, not only the protrusion 28 but also the entire end region 20 deforms, absorbing the impact energy. This effectively prevents stress concentration near the base of the protrusion 28, leading to abrupt bending and fracture of the protrusion 28, and prevents the bent portion R from having sharp corners.

[0048] Furthermore, in this example, the manufacturing process for bumper RF10 can be simplified compared to the second comparative example. Specifically, in the second comparative example, the cutout 22 that divides the vehicle-widthwise end portion of bumper RF10 into the front end portion 24 and the rear end portion 26 is not formed. Therefore, in the second comparative example, to tilt the front wall 12 relative to the rear wall 14 at the vehicle-widthwise end portion of the square tubular member, the vehicle-widthwise end portion is heated to soften it, and then pressure is applied to the vehicle-widthwise end portion to compress and deform the transverse wall 16. However, this heating and pressurizing process is very laborious.

[0049] On the other hand, in this example, the front wall 12 is tilted relative to the rear wall 14 by cutting off a portion of the transverse wall 16 and then bending the front end 24. In other words, in this example, heating of the end region 20 and compressive deformation of the transverse wall 16 are unnecessary, and thus the manufacturing process of the bumper RF10 can be further simplified compared to the second comparative example.

[0050] As can be seen from the above description, the bumper RF10 of this example can effectively prevent the end of the bumper RF10 from violently digging into an obstacle when it collides with an obstacle. It should be noted that the structure described so far is merely an example. As long as the end region 20 of the bumper RF10 is formed with a cutout 22 that divides the end region 20 into a front end 24 and a rear end 26, and the front end 24 is bent rearward and has a protrusion 28 that protrudes outward in the vehicle width direction from the end of the rear end 26, other structures may be modified. For example, while three transverse walls 16 are provided in the above description, the number of transverse walls 16 may be varied as appropriate. Furthermore, the ratio of the protrusion amount L1 of the protrusion 28 to the thickness dimension L2 may be varied as appropriate. For example, the protrusion amount L1 may be varied within a range of 0.5 to 2 times the thickness dimension L2. Furthermore, the shape of the cutout 22 may be varied; for example, the front-to-back dimension of the cutout 22 may be constant.

Claims

1. A bumper reinforcement extending in the vehicle width direction at the front of a vehicle, characterized in that: have: anterior wall; a rear wall located further rearward than the front wall; One or more transverse walls connecting the front wall and the rear wall; and The cutout extends from the end of the transverse wall in the vehicle width direction toward the inner side in the vehicle width direction, The region of the end portion in the vehicle width direction of the bumper reinforcement is divided into a front end portion located forward of the cutout and a rear end portion located rearward of the cutout. The front end portion is bent rearwardly in an inclined manner relative to the rear wall and has a protruding portion that protrudes outward in the vehicle width direction from a distal end of the rear end portion in the vehicle width direction. The protrusion amount of the protrusion from the rear end portion is smaller than a dimension of the protrusion in a thickness direction.

2. The bumper reinforcement according to claim 1, characterized in that: Before the front end portion is bent rearward, the front edge of the cutout is substantially parallel to the front wall, and the rear edge of the cutout is inclined relative to the rear wall so as to approach the rear wall as it approaches the end in the vehicle width direction.

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