Bumper reinforcement

Abstract

A bumper reinforcement provided with: a base portion extending in a vehicle width direction; a protruding portion mounted to at least one end portion of the base portion in an up-down direction, protruding in the up-down direction away from the base portion, and provided with a crash box on a vehicle inner side of the base portion, the protruding portion having at least one of the following (A) and (B): (A) a length of the protruding portion in a vehicle front-rear direction is longer than a length of the base portion in the vehicle front-rear direction; and (B) a plate thickness of the protruding portion is thicker than a plate thickness of the base portion.

Description

TECHNICAL FIELD

[0001] The present specification discloses a bumper reinforcement mounted on the end portion in the vehicle front-rear direction. BACKGROUND

[0002] In Japanese Patent Application Publication No. 2003-312400, a bumper reinforcement mounted on a crash box is disclosed. The bumper reinforcement has a cylindrical shape. The length in the up-down direction of the bumper reinforcement coincides with the length in the up-down direction of the crash box. SUMMARY

[0003] In the above-described technology, when a collision against the vehicle to a position where no crash box is arranged occurs in the up-down direction, there is a case where the load of the collision cannot be borne by the bumper reinforcement.

[0004] In the present specification, a technology capable of bearing the load of a collision against the vehicle to a position where no crash box is arranged in the up-down direction by the bumper reinforcement is provided.

[0005] In the present specification, a bumper reinforcement having a cylindrical shape extending in the vehicle width direction is disclosed. The bumper reinforcement includes a base portion extending in the vehicle width direction, and a protruding portion mounted on at least one end in the up-down direction of the base portion, protruding in the up-down direction to a direction away from the base portion, a crash box being arranged on the inner side of the vehicle of the base portion, the protruding portion having at least one of (A) and (B) described below, that is, (A) the length of the protruding portion in the vehicle front-rear direction is longer than the length of the base portion in the vehicle front-rear direction, and (B) the plate thickness of the protruding portion is thicker than the plate thickness of the base portion.

[0006] According to the above-described structure, the load of a collision against the vehicle to a position where no crash box is arranged in the up-down direction can be borne by the protruding portion of the bumper reinforcement. Since the protruding portion has at least one of a portion longer in the vehicle front-rear direction than the base portion and a portion thicker in the plate thickness than the base portion, the cross-sectional moment of inertia in the vehicle front-rear direction can be increased compared to the base portion. Therefore, compared to a case where the shape of the protruding portion is a shape in which the base portion is simply extended in the up-down direction, the deformation of the protruding portion in the case of receiving the load of the collision can be suppressed. As a result, even if no crash box is arranged on the inner side of the protruding portion, the deformation of the protruding portion in the case of receiving the load of the collision can be suppressed.

[0007] Hereinafter, the technical elements of the bumper reinforcement device disclosed in the present specification are listed. In addition, each of the technical elements below is independent and useful.

[0008] Alternatively, in the aforementioned bumper reinforcement, a reinforcing wall extending in the vehicle's longitudinal direction may be disposed between the base and the protrusion, inside the bumper reinforcement.

[0009] Based on this structure, the deformation of the protrusion can be suppressed by using reinforcing walls.

[0010] Alternatively, in the bumper reinforcement, the protrusion may have a specific portion that is longer than the base in the longitudinal direction of the vehicle, and the specific portion extends into the inner side of the vehicle compared to the base.

[0011] With this structure, the bumper reinforcement does not need to extend to the side of the bumper; instead, a specific portion longer than the base is formed in the protrusion in the longitudinal direction of the vehicle. This avoids widening the gap between the base of the bumper reinforcement and the bumper.

[0012] In the aforementioned bumper reinforcement, the specific portion may have an inclined surface, which is an inclined surface extending from one end of the base toward a direction away from the base and inclined toward the inside of the vehicle.

[0013] According to this structure, by configuring the inclined surface, the length of a specific section in the longitudinal direction of the vehicle can be gradually increased from the base. This prevents a step difference from occurring at the junction of the base and the specific section. As a result, stress concentration due to collision loads at the junction of the base and the specific section can be suppressed.

[0014] In the aforementioned bumper reinforcement, the protrusion may be installed at both ends of the base in the vertical direction, and the protrusion at the upper end of the base may have a shape obtained by reversing the protrusion at the lower end of the base in the vertical direction.

[0015] Alternatively, in the aforementioned bumper reinforcement, the collision box may not be configured on the inner side of the protrusion within the vehicle.

[0016] Another embodiment of the present invention provides a bumper reinforcement having a cylindrical shape extending in the vehicle width direction. The bumper reinforcement includes: a base extending in the vehicle width direction; and a protrusion mounted on at least one end of the base in a vertical direction, protruding in the vertical direction in a direction away from the base. A collision box is disposed inside the vehicle on the base, and no collision box is disposed inside the vehicle on the protrusion. The thickness of the protrusion is greater than the thickness of the base. The length of the protrusion in the vehicle longitudinal direction is the same as the length of the base in the vehicle longitudinal direction.

[0017] Alternatively, in the aforementioned bumper reinforcement, the collision box may not be configured on the inner side of the protrusion within the vehicle. Attached Figure Description

[0018] The features, advantages, and technical and industrial significance of embodiments of the present invention will now be described with reference to the accompanying drawings, in which similar reference numerals denote similar parts, wherein:

[0019] Figure 1 This is a perspective view showing a portion of the rear side of the vehicle according to the first embodiment.

[0020] Figure 2 This is a top view showing the bumper reinforcement and collision box of the first embodiment.

[0021] Figure 3 It means Figure 2 Cross-sectional view of section III-III.

[0022] Figure 4 This is a cross-sectional view showing section III-III of the second embodiment.

[0023] Figure 5 This is a cross-sectional view showing section III-III of the third embodiment. Detailed Implementation

[0024] (First implementation method)

[0025] like Figure 1 As shown, the bumper reinforcement 10 of this embodiment is disposed at the rear end of the vehicle 2. The bumper reinforcement 10 is disposed on the inner side of the rear bumper 6 located at the rear end of the vehicle, that is, on the front side of the rear bumper 6. When the vehicle 2 is subjected to a rear-end collision, the bumper reinforcement 10 bears the load and suppresses the deformation of the vehicle 2.

[0026] like Figure 2 As shown, the bumper reinforcement 10 extends in the vehicle width direction, i.e., the left-right direction. In the bumper reinforcement 10, the central portion in the vehicle width direction extends parallel to the vehicle width direction, while the two end portions in the vehicle width direction are inclined forward. The two end portions of the bumper reinforcement 10 in the vehicle width direction are connected to the crash box 100. The bumper reinforcement 10 is fixed to the crash box 100, for example, by bolts. The crash box 100 has a generally quadrangular cylindrical shape, which has an axial direction parallel to the vehicle's front-rear direction. The crash box 100 is connected at its front end to the rear end of the side beam 200. The side beam 200 is mounted to the inner side of the wheel 3 at both ends of the floor 8 in the vehicle width direction.

[0027] like Figure 3As shown, the bumper reinforcement 10 is positioned with a slight gap relative to the rear bumper 6. The bumper reinforcement 10 has an outer peripheral wall 11 with a generally hexagonal cylindrical shape. The bumper reinforcement 10 is manufactured by extrusion molding of aluminum alloy. In the bumper reinforcement 10, the outer peripheral wall 11 has the same cross-sectional shape perpendicular to the axial direction along its entire length in the vehicle width direction. The bumper reinforcement 10 has a plurality of reinforcing walls 16 disposed within the outer peripheral wall 11 between a pair of wall portions facing each other in the vehicle's longitudinal direction. Each of the plurality of reinforcing walls 16 has a flat plate shape. The reinforcing walls 16 are disposed along the entire length in the vehicle width direction. From the front end to the rear end of the bumper reinforcement 10, the reinforcing walls 16 are disposed parallel to the vehicle's longitudinal direction.

[0028] The bumper reinforcement 10 includes a base 12 and a protrusion 14. The base 12 extends vertically from the upper end of the bumper reinforcement 10, i.e., the upper end of the outer peripheral wall 11, to the reinforcement wall 16 disposed at approximately the same height as the lower end of the collision box 100. The base 12 has a rectangular shape in a cross-section perpendicular to the vehicle width direction. The upper wall 12a disposed at the upper end of the base 12 is located slightly above the upper end of the collision box 100. At the front end of the upper wall 12a, a front wall 12b perpendicular to the vehicle's longitudinal direction is disposed. At the rear end of the upper wall 12a, a rear wall 12c perpendicular to the vehicle's longitudinal direction and parallel to the front wall 12b is disposed.

[0029] Multiple reinforcing walls 16 are arranged perpendicularly to the front wall 12b and the rear wall 12c between them. The lower end of the base 12 is located slightly below the lower end of the collision box 100. That is, the collision box 100 is arranged in front of the vehicle along approximately its entire length in the vertical direction. In the base 12, a reinforcing wall 16 is arranged at the middle position in the vertical direction. The upper wall 12a, the front wall 12b, the rear wall 12c, and the multiple reinforcing walls 16 have the same plate thickness.

[0030] A reinforcing wall 16 is disposed at the lower end of the base 12. Below the base 12, a protrusion 14 protrudes downward from the lower end of the base 12. A reinforcing wall 16 is disposed between the base 12 and the protrusion 14. The protrusion 14 is disposed along the entire length of the bumper reinforcement 10 in the vehicle width direction. The protrusion 14 is located downward from the lowermost reinforcing wall 16. A rear wall 14c disposed at the rear end of the protrusion 14 is disposed on an extension of the rear wall of the base 12. The protrusion 14 has a flat, inclined wall (inclined surface) 14a at its front end, which slopes forward from the lower end of the base 12. A front wall 14b is connected to the lower end of the inclined wall 14a. The front wall 14b is parallel to the rear wall 14c in the vertical direction. The front wall 14b and the rear wall 14c are connected at their lower ends via a lower wall 14d extending in the vehicle longitudinal direction. The lower wall 14d has a flat plate shape arranged perpendicular to the vertical direction. The length of the protrusion 14 in the vehicle longitudinal direction is longer than the length of the base 12 in the vehicle longitudinal direction.

[0031] Inclined wall 14a, front wall 14b, rear wall 14c and lower wall 14d are included in the outer peripheral wall 11. The outer peripheral wall 11 is composed of inclined wall 14a, front wall 14b, rear wall 14c, lower wall 14d and upper wall 12a, front wall 12b and rear wall 12c.

[0032] The inclined walls 14a, front wall 14b, rear wall 14c, and lower wall 14d constituting the protrusion 14 have the same plate thickness. The plate thickness of the inclined walls 14a, front wall 14b, rear wall 14c, and lower wall 14d (hereinafter referred to as "plate thickness of the protrusion 14") is thicker than the plate thickness of the upper wall 12a, front wall 12b, rear wall 12c, and the plurality of reinforcing walls 16 constituting the base 12 (hereinafter referred to as "plate thickness of the base 12").

[0033] When a vehicle or similar object collides with vehicle 2 from behind, the bumper 6 deforms due to the forward load generated by the collision, and this load is applied to the bumper reinforcement 10. When the collision load, as indicated by the arrow representing load L1, is applied at the height where the collision box 100 is located, load L1 is borne by the bumper reinforcement 10 and the collision box 100. This prevents the bumper reinforcement 10 from undergoing large forward displacement due to the load. As a result, deformation of the bumper 6 is suppressed.

[0034] On the other hand, if the collision load, as indicated by the arrow representing load L2, is applied at a height where the collision box 100 is not located, there is no load-bearing member in the bumper reinforcement 10 at the front of the vehicle along the extension line of the load L2 direction. Therefore, if the protrusion 14 has the same length in the vehicle's longitudinal direction as the base 12 and has the same plate thickness as the base 12, even if the load L1 and load L2 are equal, the displacement of the bumper reinforcement 10 under load L2 will become greater than the displacement of the bumper reinforcement 10 under load L1.

[0035] The protrusion 14 is combined with the upper reinforcing wall 16 and has a hollow tube shape. Therefore, the longer the length in the longitudinal direction, the greater the moment of inertia (hereinafter simply referred to as "moment of inertia") of the protrusion 14 in the longitudinal direction of the vehicle. The protrusion 14 is longer than the base 12 in the longitudinal direction. Thus, compared to simply making the protrusion 14 with the same length in the longitudinal direction as the base 12, the moment of inertia of the protrusion 14 can be increased. In addition, the thicker the plate, the greater the moment of inertia of the protrusion 14. The plate thickness of the protrusion 14 is greater than the plate thickness of the base 12. Thus, compared to simply making the protrusion 14 with the same plate thickness as the base 12, the moment of inertia of the protrusion 14 can be increased. According to this structure, displacement of the protrusion 14 can be suppressed. As a result, deformation of the bumper 6 can be suppressed.

[0036] When the bumper 6 deforms and bulges upwards, it interferes with the lower end of the trunk door 4, making it impossible to open the trunk door 4. By using the bumper reinforcement 10 to suppress the deformation of the bumper 6, this situation of being unable to open the trunk door 4 can be avoided.

[0037] For example, the bumper reinforcement 10 is particularly useful for vehicles 2 with a relatively high vehicle height. When the vehicle height is high, the floor 8 is positioned higher, as are the side beams 200 and the impact box 100. When a vehicle with a relatively low vehicle height collides with the rear of vehicle 2, there is a possibility that the impact with the bumper 6 occurs at a position lower than the impact box 100, with the load applied at the position of load L2. By using the bumper reinforcement 10, large deformations of the bumper reinforcement 10 and the bumper 6 can be suppressed in such low-position collisions. In particular, for relatively small loads such as collisions with other vehicles at low speeds from behind vehicle 2, deformation of the bumper 6 can be suppressed by inhibiting the deformation of the protrusion 14.

[0038] A reinforcing wall 16 is disposed at the upper end of the protrusion 14. The protrusion 14 and the reinforcing wall 16 form a cylindrical shape. Thus, the protrusion 14 can be reinforced by the reinforcing wall 16. In addition, in a modified example, more than one reinforcing wall may be disposed on the protrusion 14. The more than one reinforcing wall may extend from at least one of the inclined wall 14a and the front wall 14b to the rear wall 14c, and may be parallel to the front-rear direction or inclined. In addition, the thickness of the reinforcing wall 16 located at the upper end of the protrusion 14 may be the same as the thickness of the protrusion 14.

[0039] The protrusion 14 extends forward of the vehicle, i.e., inward, compared to the base 12, below the collision box 100. In a typical vehicle 2, there is no structural component positioned below the collision box 100, leaving space. Therefore, it is not necessary to reconfigure the structural components of the vehicle 2 to ensure the length of the protrusion 14 in the longitudinal direction. Furthermore, the protrusion 14 extends inward. Therefore, it is not necessary to separately mount the bumper 6 from the bumper reinforcement 10 to ensure the length of the protrusion 14 in the longitudinal direction.

[0040] In the protrusion 14, the inclined wall 14a slopes downwards from the lower end of the base 12 toward the inside of the vehicle, i.e., the front side of the vehicle. As a result, a step difference can be prevented at the junction of the protrusion 14 and the base 12. Thus, stress concentration at the junction of the base 12 and the protrusion 14 due to collision load can be suppressed.

[0041] (Second implementation method)

[0042] like Figure 4 As shown, the bumper reinforcement 210 is equipped with a protrusion 214 instead of the protrusion 14. Additionally, the bumper reinforcement 210 is equipped with a protrusion 216. The other structures of the bumper reinforcement 210 are the same as those of the bumper reinforcement 10.

[0043] Compared to protrusion 14, protrusion 214 is thinner than protrusion 14, but has the same thickness as base 12. The other structural features of protrusion 214 are the same as those of protrusion 14.

[0044] The protrusion 216 is located above the upper wall 12a at the upper end of the base 12. The shape of the protrusion 216 is such that the protrusion 214 is reversed vertically. According to this structure, the deformation of the bumper reinforcement 210 can be suppressed for loads above the base 12.

[0045] In a modified example, the thickness of protrusions 214 and 216 may be the same as the thickness of protrusion 14. Alternatively, the bumper reinforcement 210 may not have either protrusion 214 or protrusion 216.

[0046] (Third implementation method)

[0047] like Figure 5 As shown, the bumper reinforcement 310 is equipped with a protrusion 314 in place of the protrusion 14. The other structures of the bumper reinforcement 310 are the same as those of the bumper reinforcement 10.

[0048] The protrusion 314 has a front wall 314b, a rear wall 314c, and a lower wall 314d. The rear wall 314c is the same as the rear wall 14c. The front wall 314b is disposed on an extension of the front wall 12b. That is, the length of the protrusion 314 in the vehicle longitudinal direction is the same as the length of the base 12 in the vehicle longitudinal direction. The lower wall 314d is connected to the front wall 314b and the rear wall 314c at the lower end of the protrusion 314. The plate thickness of the protrusion 314 is the same as the plate thickness of the protrusion 14.

[0049] In a modified example, the bumper reinforcement 310 may also be equipped with a protrusion with the same structure as the protrusion 314 above the base 12.

[0050] The above description provides specific examples of the present invention; however, these are merely examples and do not limit the scope of the claims. The technology described within the scope of the claims includes embodiments derived from various modifications and alterations of the specific examples illustrated above.

[0051] The protrusion 14 may not extend across the entire length of the bumper reinforcement 10 in the vehicle width direction, i.e., the left-right direction. For example, the protrusion 14 may only be positioned at locations with a higher probability of collision in the vehicle width direction. The same applies to protrusions 214, 216, and 314.

[0052] The protrusion 14 may also extend rearward beyond the base 12. The same applies to protrusions 214 and 216.

[0053] Bumper reinforcement parts 10, 210, and 310 can also be installed on the inside of the front bumper at the front of the vehicle.

[0054] The cross-sectional shape of the bumper reinforcement 10 in the direction perpendicular to the vehicle width direction may not be consistent along its entire length in the vehicle width direction. For example, for areas with a higher probability of collision in the vehicle width direction, at least one of the base 12 and the protrusion 14 may be configured with a cross-sectional shape that increases the moment of inertia. The same applies to the bumper reinforcements 210 and 310. For example, in the protrusion 14, on the one hand, the cross-sectional shape of the protrusion 14 may be used in areas with a higher probability of collision in the vehicle width direction, and on the other hand, the cross-sectional shape of the protrusion 214 or the cross-sectional shape of the protrusion 314 may be used in other areas.

[0055] Furthermore, the technical elements described in this specification or drawings may exert their technical usefulness individually or in various combinations, and are not limited to the combinations recorded in the claims at the time of application. Additionally, the technologies illustrated in this specification or drawings may achieve multiple objectives simultaneously, but achieving even one of these objectives is technically useful in itself.

Claims

1. A bumper reinforcement having a cylindrical shape extending in the width direction of the vehicle, characterized in that, include: A base that extends in the vehicle width direction; as well as A protrusion is mounted on at least one end of the base in the vertical direction and protrudes away from the base in the vertical direction. A collision box is disposed inside the vehicle at the base, and the inner end of the collision box is connected to the outer end of the vehicle's side beam. The protrusion has at least one of the following (A) and (B): (A) The length of the protrusion in the longitudinal direction of the vehicle is longer than the length of the base in the longitudinal direction of the vehicle. (B) The thickness of the protrusion is greater than the thickness of the base. The protrusion has a specific portion that is longer than the base in the longitudinal direction of the vehicle. The specific portion extends into the interior of the vehicle compared to the base. The specific portion has an inclined surface that extends from one end of the base in a direction away from the base and slopes inward toward the inside of the vehicle. The inclined surface separates from the wall portion of the collision box, and extends further away from the wall portion of the collision box as it extends in the direction of separation from the base portion.

2. The bumper reinforcement as described in claim 1, characterized in that, Between the base and the protrusion, a reinforcing wall extending in the longitudinal direction of the vehicle is disposed inside the bumper reinforcement.

3. The bumper reinforcement as described in claim 1 or 2, characterized in that, The protrusion is mounted at both ends of the base in the vertical direction, and the protrusion at the upper end of the base has a shape obtained by reversing the protrusion at the lower end of the base in the vertical direction.

4. The bumper reinforcement as described in claim 1 or 2, characterized in that, The collision box is not disposed on the inside of the vehicle at the protrusion.

Images