CN107953847B

CN107953847B - Energy absorption box

Info

Publication number: CN107953847B
Application number: CN201711228816.XA
Authority: CN
Inventors: 吴昌生; 胡涛; 赵雪梅; 邓高福
Original assignee: Dongfeng Motor Co Ltd
Current assignee: Dongfeng Motor Co Ltd
Priority date: 2017-11-29
Filing date: 2017-11-29
Publication date: 2020-07-21
Anticipated expiration: 2037-11-29
Also published as: CN107953847A

Abstract

The invention discloses an energy absorption box which comprises a hollow box body with a rectangular cross section, wherein the hollow box body comprises an upper shell and a lower shell, the upper shell comprises a top surface and two first side walls, the lower shell comprises a bottom surface and two second side walls, the first side walls are in butt joint with the second side walls, and the section counter force of the upper shell is smaller than that of the lower shell. The energy absorption box is divided into an upper shell and a lower shell, and the section counter force of the upper shell is smaller than that of the lower shell. When the protruding part of the offset collision barrier collides with the energy absorption box in a collision test, the energy absorption box is prevented from bending downwards in the offset collision, and further the deformation mode of subsequent structures such as the front longitudinal beam is prevented from being influenced.

Description

Energy absorption box

Technical Field

The invention relates to the field of automobiles, in particular to an energy absorption box.

Background

With the fact that tires of compact three-compartment vehicles are larger and larger, and a large number of compact SUVs emerge, when a high-attitude compact vehicle type is subjected to 40% offset collision (hereinafter referred to as offset collision) of a C-NCAP 64KM/H collapsible barrier, the situation that the overlapping amount of a BMPR STAY and a protruding part of the barrier is only half (or less than half) must be faced, and because the auxiliary frame cannot provide powerful support below the auxiliary frame in the early stage of the collision, the energy absorption box is almost inevitable to bend downwards, the energy absorption of the energy absorption box can be influenced, the deformation modes of a subsequent front longitudinal beam and the auxiliary frame are directly influenced, the original structure which always meets the requirements can be caused, the requirement is not met after the vehicle attitude is improved, and the influence cannot be ignored even more when the tolerance of the C-NCAP experiment has a tolerance of +/-10 mm in the height direction.

Therefore, it is necessary to design a crash box that can prevent the crash box from bending down during offset collision and affecting the deformation mode of the subsequent structures such as the front side member, etc., in the case where the overlapping amount of the crash box and the protruding portion of the barrier is small.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide an energy-absorbing box which can avoid the energy-absorbing box from bending downwards in offset collision and influencing the deformation mode of subsequent structures such as a front longitudinal beam and the like under the condition that the overlapping amount of the energy-absorbing box and the protruding part of a barrier is small.

The invention provides an energy absorption box which comprises a hollow box body with a rectangular cross section, wherein the hollow box body comprises an upper shell and a lower shell, the upper shell comprises a top surface and two first side walls, the lower shell comprises a bottom surface and two second side walls, the first side walls are in butt joint with the second side walls, and the section counter force of the upper shell is smaller than that of the lower shell.

Further, when the upper shell and the lower shell are made of the same material, the wall thickness of the upper shell is smaller than that of the lower shell.

Further, the tensile strength of the material of the upper shell is less than the tensile strength of the material of the lower shell.

Furthermore, the tensile strength of the material of the upper shell is 270 Mpa-590 Mpa, and the wall thickness is 1.0 mm-2.3 mm; the tensile strength of the material of the lower shell is 370 Mpa-780 Mpa, and the wall thickness is 1.0 mm-2.3 mm.

Further, the height of the upper housing is greater than the height of the lower housing.

Further, the height ratio of the upper shell to the lower shell is 1.2: 1-4: 1.

Furthermore, the top surface of the upper shell is provided with a collapse rib, and the bottom surface of the lower shell is not provided with the collapse rib.

Furthermore, the first side wall of the upper shell is provided with the collapse rib, and the second side wall of the lower shell is also provided with the collapse rib.

Further, the adjacent collapse ribs on the same surface are spaced into convex ribs and concave ribs.

Further, the connected collapse ribs on the two adjacent surfaces are respectively a convex rib and a concave rib.

Furthermore, the plurality of collapse ribs are distributed on the wave crests or wave troughs of the deformation sine waves of the energy absorption box along the front-back direction of the vehicle body, and the energy absorption box comprises 1-5 deformation sine half waves.

After adopting above-mentioned technical scheme, have following beneficial effect:

the energy absorption box is divided into an upper shell and a lower shell, and the section counter force of the upper shell is smaller than that of the lower shell. When the protruding part of the offset collision barrier collides with the energy absorption box in a collision test, the energy absorption box is prevented from bending downwards in the offset collision, and further the deformation mode of subsequent structures such as the front longitudinal beam is prevented from being influenced.

Drawings

The disclosure of the present invention will become more readily understood by reference to the drawings. It should be understood that: these drawings are for illustrative purposes only and are not intended to limit the scope of the present disclosure. In the figure:

FIG. 1 is a schematic illustration of a construction in which a crash box according to an embodiment of the invention is mounted to a vehicle body;

FIG. 2 is a perspective view of an energy absorption box according to an embodiment of the present invention;

FIG. 3 is a schematic view of the construction of a barrier and crash box in accordance with an embodiment of the present invention;

FIG. 4 is a cross-sectional view of an energy absorption box in an embodiment of the present invention;

FIG. 5 is a distribution of crush ribs of the energy absorber can in one embodiment of the present invention;

FIG. 6 is an enlarged, fragmentary view of a crush rib of the energy absorber box in accordance with one embodiment of the present invention;

FIG. 7 is a schematic view of an energy absorption box according to yet another embodiment of the present invention including a distorted sinusoidal half wave;

FIG. 8 is a schematic view of an energy absorption box according to another embodiment of the present invention including two distorted sinusoidal half waves;

FIG. 9 is a schematic view of an energy absorption box according to yet another embodiment of the present invention including four distorted sinusoidal half waves;

FIG. 10 is a schematic illustration of an energy absorption box according to yet another embodiment of the present invention including five distorted sinusoidal half waves.

Reference symbol comparison table:

10-crash box 20-barrier 30-front bumper

40-front longitudinal beam 50-water tank upper cross beam 60-cabin cover edge beam

1-upper shell 2-lower shell 11-top surface

12-first side wall 21-second side wall 201-protrusion

111-collapse rib 112-collapse rib 113-collapse rib

121-collapse rib 122-collapse rib 123-collapse rib

211-collapse rib 212-collapse rib

Detailed Description

The following further describes embodiments of the present invention with reference to the accompanying drawings.

It is easily understood that according to the technical solution of the present invention, those skilled in the art can substitute various structures and implementation manners without changing the spirit of the present invention. Therefore, the following detailed description and the accompanying drawings are merely illustrative of the technical aspects of the present invention, and should not be construed as limiting or restricting the technical aspects of the present invention.

The terms of orientation of up, down, left, right, front, back, top, bottom, and the like referred to or may be referred to in this specification are defined relative to the configuration shown in the drawings, and are relative terms, and thus may be changed correspondingly according to the position and the use state of the device. Therefore, these and other directional terms should not be construed as limiting terms.

The direction of the invention is based on the direction of the whole automobile. X, Y, Z are included in the figure. The X direction is the front-rear direction of the automobile, the Y direction is the left-right direction of the automobile, and the Z direction is the up-down direction of the automobile.

As shown in fig. 1, the vehicle body according to an embodiment of the present invention includes a front bumper 30, a front side member 40, and a crash box 10, wherein the crash box 10 is located between the front bumper 30 and the front side member 40. A water tank upper cross beam 50 is further arranged between the energy absorption box 10 and the front longitudinal beam 40, and the rear end of the water tank upper cross beam 50 is further connected with a cabin cover side beam 60.

When a collision test is performed, the barrier 20 is needed, and the protrusion 201 is arranged below the barrier 20. In the collision, the projection 201 collides with the vehicle body first. When the vehicle posture is raised, the test position of the barrier 20 is unchanged, and the heights of the front bumper 30, the crash box 10 and the front longitudinal beam 40 are raised. Therefore, the amount of overlap between the protruding portion 201 and the front bumper 30 and the crash box 10 is reduced. The cross section counter forces of the upper part and the lower part of the traditional energy-absorbing box are the same, so that the lower half part of the energy-absorbing box is firstly collapsed during collision, the energy-absorbing box is bent downwards, and the deformation modes of subsequent structures such as a front longitudinal beam and the like are influenced.

The section reaction force is as follows: when the sheet metal structural part is subjected to axial or eccentric axial stress, the sheet metal structural part has the mechanical property of a resisting structure, and is called section reaction force when being specific to each section (section). The conventional method for obtaining the section reaction force includes the steps of intercepting through CAE software, calculating through section analysis software, calculating through a sheet collapse theory, estimating through traditional material mechanics and the like.

As shown in fig. 2, the energy-absorbing box 10 according to an embodiment of the present invention includes a hollow box body with a rectangular cross section, the hollow box body is made of metal sheet, the hollow box body includes an upper shell 1 and a lower shell 2, the upper shell 1 includes a top surface 11 and two first side walls 12, the lower shell 2 includes a bottom surface (not shown) and two second side walls 21, the first side walls 12 are abutted to the second side walls 21, and a section reaction force of the upper shell 1 is smaller than a section reaction force of the lower shell 2.

In this embodiment, the crash box 10 is divided into upper and lower portions, and the cross-sectional reaction force of the upper case 1 is smaller than that of the lower case 2. When the barrier 20 collides with the crash box 10, the lower case 2 can be collapsed in synchronization with the upper case 1 although the protrusion 201 collides with the lower case 2 first due to the large section reaction force of the lower case 2. The situation that the energy absorption box 10 bends downwards is avoided, and the deformation modes of the front longitudinal beam and other subsequent structures are prevented from being impacted in a biased mode.

Preferably, the crash box 10 is a left crash box. Since crash tests are generally directed only to the left crash box, the modification of the crash box 10 of this embodiment is directed to the left crash box.

Alternatively, the crash box 10 can also be a right crash box, or both the left and right crash boxes can be modified.

Alternatively, when the upper case 1 and the lower case 2 are made of the same material, the wall thickness of the upper case 1 is smaller than that of the lower case 2.

Since the wall thickness of the upper case 1 is thinner than that of the lower case 2, the cross-sectional reaction force of the upper case 1 is smaller than that of the lower case 2.

Optionally, the tensile strength of the material of the upper shell 1 is less than the tensile strength of the material of the lower shell 2. When the wall thicknesses of the upper case 1 and the lower case 2 are the same, the cross-sectional reaction force of the upper case 1 may be smaller than the cross-sectional reaction force of the lower case 2.

Preferably, the tensile strength of the material of the upper shell 1 is 270MPa to 590MPa, and the wall thickness is 1.0mm to 2.3 mm; the tensile strength of the material of the lower shell 2 is 370 Mpa-780 Mpa, and the wall thickness is 1.0 mm-2.3 mm.

Further, as shown in fig. 2 to 4, the height of the upper case 1 is greater than that of the lower case 2. The heights of the upper shell 1 and the lower shell 2 are along the Z direction of the whole vehicle.

After the vehicle posture is raised, the height of the crash box 10 is also raised. The upper surface of the protrusion 201 of the barrier 20 is lowered with respect to the bottom surface of the crash box 10 at a position corresponding to the crash box 10. Therefore, the height of the upper case 1 is set to be greater than the height of the lower case 2 such that the parting line (horizontal dotted line in fig. 3) of the upper case 1 and the lower case 2 is at the same height or close to the upper surface of the protrusion 201 of the barrier 20. It is advantageous to control the crash test effect of the crash box 10 by dividing the upper case 1 and the lower case 2 by the horizontal line of the upper surface of the protrusion 201 such that the protrusion 201 collides with the lower case 2 first. The crash box 10 can be prevented from being bent downward by adjusting the cross-sectional reaction force, the tensile strength of the material, or the wall thickness of the upper case 1 and the lower case 2.

Preferably, the height ratio of the upper shell 1 to the lower shell 2 is 1.2:1 to 4: 1.

Further, as shown in fig. 2, the upper case 1 is provided with crush ribs (111, 112, 113) on the top surface 11, and the lower case 2 is not provided with crush ribs on the bottom surface. The provision of the crush ribs of the upper case 1 makes the upper case 1 more likely to collapse.

Further, as shown in fig. 2, the first side wall 12 of the upper case 1 is provided with crush ribs (121, 122, 123), and the second side wall 21 of the lower case 2 is also provided with crush ribs (211, 212).

Wherein, the rib 111 that contracts bursts, the rib 121 that contracts bursts and the rib 211 that contracts burst link to each other, and the rib 113 that contracts bursts, the rib 123 that contracts burst link to each other with the rib 212 that contracts burst, and the rib 122 that contracts burst is located between the rib 121 that contracts burst and the rib 123 that contracts burst, and the rib 112 that contracts burst links to each other with the rib 122 that contracts burst, and the rib 122 that contracts burst only bursts and contracts half of the length of rib 121 and the rib 123 that contracts burst to do not have the rib that contracts burst on the lower casing 2 that corresponds.

Furthermore, adjacent crumple ribs on the same surface are respectively a convex rib and a concave rib at intervals, and the connected crumple ribs on the two adjacent surfaces are respectively a convex rib and a concave rib.

Specifically, as shown in fig. 2, the

crush ribs

111, 112, and 113 are spaced as convex ribs and concave ribs on the top surface 11 of the upper case 1. Namely, the collapse rib 111 is a convex rib, the collapse rib 112 is a concave rib, and the collapse rib 113 is a convex rib.

On the first side wall 12 of the upper case 1, the

collapse ribs

121, 122 and 123 are convex ribs and concave ribs. And the top surface 11 and the first sidewall 12 are adjacent surfaces, so the collapse rib 121 is a concave rib, the collapse rib 122 is a convex rib, and the collapse rib 123 is a concave rib.

On the second side wall 21 of the lower housing 2, since the collapsing rib 211 is connected to the collapsing rib 121, the collapsing rib 212 is connected to the collapsing rib 123, and the first side wall 12 and the second side wall 21 are adjacent surfaces, the collapsing rib 211 is a concave rib, and the collapsing rib 212 is a concave rib.

The mode of arranging the convex ribs and the concave ribs at intervals is favorable for the stability of deformation.

Furthermore, the plurality of collapse ribs are distributed on the wave crests or wave troughs of the deformation sine waves of the energy absorption box 10 along the front and back directions of the vehicle body, and 1-5 deformation sine half waves are distributed on the energy absorption box 10.

The deformation sine wave refers to the deformation trend waveform of the energy absorption box when the energy absorption box is collapsed, the energy absorption box is in a fold shape after being deformed, and the deformation positive dazzling wave shows the number of folds and the direction of the folds. The 'deformed sine half wave' is a half deformed sine wave with one wave crest or one wave trough. The collapse ribs are arranged on wave crests or wave troughs of the deformed sine waves, and can play a role in guiding collapse deformation, so that the energy absorption box can be controllably deformed.

In this embodiment, as shown in fig. 5, the number of deformed half-sine waves of the crash box 10 is N, where N is 3, and there are 3 sets of crush ribs in the front-rear direction. The ratio of the distance between the 3 groups of the collapse ribs of the energy absorption box 10 and the front end A and the rear end B of the energy absorption box is 1:2:2: 1. The outer sides of the front end and the rear end of the energy absorption box are reserved with certain process sizes.

Since the overall length of the crash box 10 is limited by the space inside the vehicle body, the overall length is generally determined. The portion of the crash box 10 between the two process dimensions is the crush deformed portion. When N is 3, there are 2 crests and 1 trough, consequently along the fore-and-aft direction of automobile body, are provided with three group's the muscle that bursts, and the muscle that bursts of crest department all has the setting at top surface 11, first lateral wall 12 and second lateral wall 21, and the muscle that bursts of trough department only has the setting on top surface 11 and first lateral wall 12 to the length of the muscle that bursts on first lateral wall 12 is shorter.

As shown in fig. 7-10, for the same reason: when N is 1, the distance ratio of 1 group of crumple ribs to the front end A and the rear end B of the energy-absorbing box is 1: 1; when N is 2, the distance ratio of the 2 groups of collapse ribs to the front end A and the rear end B of the energy absorption box is 1:2: 1; when N is 4, the distance ratio of the 4 groups of crumpling ribs to the front end A and the rear end B of the energy absorption box is 1:2:2:2: 1; when N is 5, the distance ratio of the 5 groups of the crumpling ribs to the front end A and the rear end B of the energy absorption box is 1:2:2:2: 1.

In the embodiment, as shown in fig. 6, the cross section of the collapse rib at the concave rib is semicircular, the concave depth is 1-8mm, the length is 1-2L, the deeper the concave depth is, the smaller the section peak value counter force is, and vice versa, and the longer the length is, the smaller the section peak value counter force is, the smaller the section counter force fluctuation is, and vice versa.

The crush ribs are arranged along the crush direction of the crash box 10, which is the front-rear direction of the vehicle body. The lengthwise direction of the crush ribs on the top surface 11 is in the left-right direction, and the lengthwise direction on the first side wall 12 and the second side wall 21 is in the up-down direction, but the width of the crush ribs is arranged in the front-rear direction.

As shown in fig. 4, a certain amount of overlap exists between the joints of the upper casing 1 and the lower casing 2, that is, a certain amount of overlap exists between the first side wall 12 and the second side wall 21, and the amount of overlap is 16 mm. The overlapping portions may be joined by spot welding, arc welding, laser tailor welding or other joining means.

The foregoing is considered as illustrative only of the principles and preferred embodiments of the invention. It should be noted that, for those skilled in the art, several other modifications can be made on the basis of the principle of the present invention, and the protection scope of the present invention should be regarded.

Claims

1. An energy absorption box comprises a hollow box body with a rectangular cross section, and is characterized in that the hollow box body comprises an upper shell and a lower shell, the upper shell comprises a top surface and two first side walls, the lower shell comprises a bottom surface and two second side walls, the first side walls are in butt joint with the second side walls, the section counter force of the upper shell is smaller than that of the lower shell, the hollow box body is installed between a front bumper and a front longitudinal beam, the upper shell and the lower shell are in planar contact connection with the front bumper, and the energy absorption box extends along the length direction of the front longitudinal beam;

the parting line between the upper shell and the lower shell is on the same height with the upper surface of the protruding part of the barrier, and the parting line horizontally extends along the central axis of the front longitudinal beam.

2. The crash box of claim 1, wherein said upper shell has a wall thickness less than a wall thickness of said lower shell when said upper shell and said lower shell are formed from the same material.

3. The crash box of claim 1, wherein said upper shell has a material tensile strength less than a material tensile strength of said lower shell.

4. The crash box of claim 3, wherein said upper shell is formed from a material having a tensile strength of 270Mpa to 590Mpa and a wall thickness of 1.0mm to 2.3 mm; the tensile strength of the material of the lower shell is 370 Mpa-780 Mpa, and the wall thickness is 1.0 mm-2.3 mm.

5. The crash box of claim 1, wherein a height of said upper shell is greater than a height of said lower shell.

6. The crash box of claim 5, wherein a ratio of a height of the upper shell to a height of the lower shell is from 1.2:1 to 4: 1.

7. An energy absorber according to any one of claims 1-6 wherein said top surface of said upper shell is provided with a crush rib and said bottom surface of said lower shell is free of said crush rib.

8. An energy absorber according to claim 7 wherein said crush ribs are provided on said first side wall of said upper shell and said crush ribs are also provided on said second side wall of said lower shell.

9. An energy absorber according to claim 8 wherein adjacent crush ribs on a surface are spaced apart by a convex rib and a concave rib.

10. An energy absorber according to claim 9 wherein said crush ribs associated with adjacent surfaces are respectively convex and concave ribs.

11. The energy absorption box according to claim 7, wherein the crush ribs are distributed on the wave crests or wave troughs of the deformation sine wave of the energy absorption box along the front-rear direction of the vehicle body, and the energy absorption box is distributed with 1-5 deformation sine half waves.