CN212407410U - Multilevel energy absorption pipe - Google Patents
Multilevel energy absorption pipe Download PDFInfo
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- CN212407410U CN212407410U CN202020595000.1U CN202020595000U CN212407410U CN 212407410 U CN212407410 U CN 212407410U CN 202020595000 U CN202020595000 U CN 202020595000U CN 212407410 U CN212407410 U CN 212407410U
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Abstract
The utility model discloses an energy-absorbing pipe of multilevel, the energy-absorbing pipe comprises two-layer pipeline wall concatenation at least, the energy-absorbing pipe includes the one-level cavity pipeline that encloses by inner pipe wall and a plurality of second grade cavity pipeline that adjacent two-layer pipeline wall concatenation formed, the cavity pipeline is arranged in the second grade the cavity pipeline is all around in the one-level. Particularly, the cross section of the energy absorption pipe is in a splicing shape of n sinusoidal corrugations, and the wave troughs of the outer layer sinusoidal corrugations in every two sinusoidal corrugations spliced on the cross section of the energy absorption pipe are tangent to the wave crests of the inner layer sinusoidal corrugations; the other structure is a double-layer energy absorption pipe, and the wave crests and the wave troughs of two sine waves spliced on the cross section of the double-layer energy absorption pipe are opposite one to one. The improved energy absorption tube structure is utilized to ensure that the mutual action of the inner layer tube and the outer layer tube in the deformation process plays a stabilizing role, the deformation is improved, and the energy absorption effect is improved.
Description
Technical Field
The utility model belongs to the technical field of the car collision, concretely relates to energy-absorbing pipe of multilevel.
Background
Thin-walled structures are widely used due to their low cost and high energy absorption characteristics. Among them, thin-walled round tubes are one of the most widely used energy absorbing structures. Conventional tubulars tend to exhibit a high initial peak force and a large fluctuation in force when subjected to axial impact loads. A greater initial peak force will result in greater acceleration during impact, increasing occupant injury. Many researchers have reduced the initial peak force effect by introducing corrugations in the axial direction, but at the same time, the structure is reduced compared with the energy-absorbing SEA, and the energy-absorbing effect of the structure is weakened.
Xiaolin Deng et al have proposed a single-layer transverse sine-wave bellows energy-absorbing structure, and compared with a common circular tube, the single-layer transverse sine-wave bellows energy-absorbing structure achieves the effect of improving the energy-absorbing characteristic of the structure, but still has the problem of unstable deformation mode.
SUMMERY OF THE UTILITY MODEL
The utility model aims at having the unstable problem of deformation mode to the horizontal sinusoidal bellows energy-absorbing structure of individual layer, provide a multilevel energy-absorbing pipe, its interact through interior outer pipe in deformation process plays stabilizing effect, improves and warp, compares and possess more energy-absorbing effect in individual layer structure.
The utility model provides a pair of multi-layer energy-absorbing pipe, the energy-absorbing pipe comprises two-layer pipeline wall concatenation at least, the energy-absorbing pipe includes the one-level cavity pipeline that encloses by inner pipe wall and a plurality of second grade cavity pipeline that adjacent two-layer pipeline wall concatenation formed, the cavity pipeline is arranged in the second grade around the cavity pipeline in the one-level, the cross section of energy-absorbing pipe is n sinusoidal ripple concatenation shape, and n does the level number of energy-absorbing pipe.
Further preferably, the wave troughs of the outer-layer sine waves in every two sine waves spliced on the cross section are tangent to the wave crests of the inner-layer sine waves, the amplitudes and the wave numbers of sine functions corresponding to the two sine waves are respectively the same, and the basic nominal radiuses are different.
The structure can effectively improve energy absorption and improve deformation stability in the collision process. In the structure, when the wave troughs of the outer sine waves in the two sine waves are tangent with the wave crests of the inner sine waves, a pore structure is generated, the inner layer wall and the outer layer wall are mutually restricted in the deformation process of the pore structure, so that the deformation process is more stable, and the hierarchical structure constructed by the adopted sine structure effectively avoids generating sharp corners at the top end; the inner and outer pipe walls meet at the tangent position to form an angular point, and the increase of the angular point improves the dissipation of the film energy of the structure in the compression process.
Preferably, the energy absorption pipe is a double-layer energy absorption pipe, peaks and troughs of two sinusoidal corrugations spliced on the cross section are opposite to each other one by one, and the amplitude, the corrugation number and the basic nominal radius of sinusoidal functions corresponding to the two sinusoidal corrugations are respectively the same.
In such a structure, the peaks and the troughs of the two sine waves are directly opposite one to one, the number of pores and the number of corner points are further increased, the deformation stability is enhanced, and the dissipation of the membrane energy in the compression process is further increased.
Further preferably, the sine function r corresponding to the sine ripple is as follows:
r=R0+A×sin(N×θ),θ∈[0°,360°]
in the formula, R0Is the basic nominal radius of the sine wave, A is the amplitude of the sine wave, N is the wave number, and N is a positive even number.
Further preferably, the amplitude a of the sinusoidal ripple is a natural number in a range of 0 to 8.
More preferably, the number of stages n of the energy absorbing pipe is 2.
Preferably, the outermost pipeline wall of the energy-absorbing pipe is provided with an opening or the top end of the outermost pipeline wall is provided with a cutting groove downwards, and the positions of the opening and the cutting groove are staggered with the joint position of the outermost pipeline wall and the adjacent inner pipeline wall.
Advantageous effects
1. The utility model provides a multilevel energy-absorbing pipe, its hierarchical structure has the improvement of showing to the holistic rigidity of structure, can make compression process's platform power show the improvement to reach the effect that improves structural energy absorption. The utility model discloses a research discovery, under the condition that does not increase structure weight, hierarchical net topological structure compares the single-deck simple structure and can show the energy-absorbing ability that improves tubular structure. The hierarchy always contains several levels of substructures, and the addition of substructures can enhance the local stiffness of the original structure, and the idea of layering the network topology can be seen as the basis for synthesizing new microstructures, resulting in enhanced or beneficial physical properties. The structural form can meet the requirements of improving mechanical performance and reducing the weight of the structure, thereby improving the energy absorption characteristic of the structure and saving the manufacturing cost. Therefore, the utility model discloses a be equipped with one-level cavity pipeline and second grade cavity pipeline and two for the level cavity pipeline arrange around the one-level cavity pipeline in the energy-absorbing pipe, and then form the net topological structure, solved the structure and can not reach the energy-absorbing effect and need increase the inconvenience that the quality brought, realize the energy-absorbing high efficiency and the lightweight of structure simultaneously. Secondly, the utility model provides a hierarchical pipe is controlled by sinusoidal function, compares the evolution of other types's multi-level energy-absorbing pipe control cross sectional shape more easily to easier processing.
2. Further, the utility model discloses utilize current sinusoidal ripple cross-section to improve, it is tangent with inlayer sinusoidal ripple's crest to provide a cross section outer sine ripple's trough in per two sinusoidal ripples of concatenation, and this structure can improve energy absorption and improve the stability of deformation effectively at the in-process that bumps. In the structure, when the wave troughs of the outer sine waves in the two sine waves are tangent with the wave crests of the inner sine waves, a pore structure is generated, the inner layer wall and the outer layer wall of the pore structure are mutually restricted in the deformation process, so that the deformation process is more stable, and the hierarchical structure constructed by the adopted sine structure effectively avoids generating sharp corners at the top end, so that the structure is torn in the compression process due to the existence of the sharp corners, and the structure is not beneficial to the practical application as an energy absorption structure; secondly, the sinusoidal structure can more easily control the evolution of the section through a function, and the cross-sectional area of the tube is increased, so that the volume of the whole structure is increased, and more energy is absorbed in the compression process. The inner and outer pipe walls meet at the tangent to form an angular point, and in energy dissipation, the film energy is mainly dissipated in the intersection region of the constituent elements, so that compared with a single-layer pipe, the increase of the angular point improves the dissipation of the film energy of the structure in the compression process.
3. Further, the utility model discloses utilize current sinusoidal ripple cross-section to improve, it is just right one by one with the trough that two sinusoidal ripple's of concatenation crest and trough are provided another kind of cross section, improvement energy absorption that this kind of structure can be further to can improve the stability and the controllability of structure at the deformation in-process. In such a structure, the peaks and the troughs of the two sine waves are directly opposite one to one, the number of pores and the number of corner points are further increased, the deformation stability is enhanced, and the dissipation of the membrane energy in the compression process is further increased.
4. In the actual collision process in the rail transit field, the safety of passengers is the primary consideration. Therefore, the utility model discloses the structure can produce a great peak force in practical application, initial stage, and can produce great acceleration when initial peak force is too big for to the damage increase of structure and passenger, on the basis of original structure, increase induced structure and reach the effect that reduces initial peak force, like surface trompil or top grooving. By making the holes or slits the stiffness of the structure can be reduced to a certain extent, so that the initial peak force is reduced somewhat, but the impact on the overall energy absorption properties is small. Aiming at the characteristics of the hierarchical structure provided by the utility model, the square groove can be cut along the axial direction at the wave crest of the outermost layer pipe, namely the intersection part of the outermost layer pipe and the inner layer pipe, and the number of the cutting grooves can be taken as the number N of the corrugations by experience; or the initial peak force is reduced by the open square holes, the circular holes and the like which are uniformly arranged along the axial direction on the outer surface of the position where the outermost layer pipe is not intersected with the inner layer pipe, and if the side length of the open square hole is 10mm or the diameter of the circular hole is 10mm, the axial opening number takes a value of [1,5 ]. By adjusting the number of the axial holes and the transverse holes or selecting the geometrical parameters (such as groove depth, groove width and the like) of the top grooving, the optimal combination can be finally realized.
Drawings
FIG. 1 is a schematic diagram of a single-layer transverse sine bellows structure, in which FIG. 1a is a perspective view of a single-layer transverse sine bellows, and FIG. 1b is a cross-sectional view of a single-layer transverse sine bellows;
FIG. 2 is a schematic structural view of a double-layer transverse sine wave bellows, wherein FIG. 2a is a perspective view of the double-layer transverse sine wave bellows, and FIG. 2b is a cross-sectional view of the double-layer transverse sine wave bellows;
FIG. 3 is a schematic structural view of a two-class double-layer transverse sine wave bellows, wherein FIG. 3a is a perspective view of the two-class double-layer transverse sine wave bellows, and FIG. 3b is a cross-sectional view of the two-class double-layer transverse sine wave bellows;
FIG. 4 is a graph comparing force-displacement curves for a single-layer tube and two types of double-layer thin-walled tubes;
FIG. 5 is a comparison graph of the specific energy absorption SEA of a single-layer tube and two types of double-layer thin-walled tubes;
FIG. 6 is a deformation mode diagram of a single-layer transverse sine corrugated pipe;
FIG. 7 is a deformation mode diagram of a double-layer transverse sine corrugated pipe;
FIG. 8 is a schematic view of a structure of increasing induction for a hierarchical structure, wherein FIG. 8a is an additional groove and FIG. 8b is an additional opening.
Detailed Description
The present invention will be further described with reference to the following examples.
The utility model provides an energy-absorbing pipe of multilevel, it comprises two-layer pipeline wall concatenation at least, and the energy-absorbing pipe includes the one-level cavity pipeline that encloses by the inlayer pipeline wall and a plurality of second grade cavity pipeline that adjacent two-layer pipeline wall concatenation formed, and the cavity pipeline is arranged all around in the one-level cavity pipeline in the second grade. Further preferably, the cross section of energy-absorbing pipe is n sinusoidal ripple concatenation shapes, is the horizontal bellows structure sketch map of thin wall as shown in fig. 1, and its cross section is sinusoidal ripple, the utility model discloses a cross section of energy-absorbing pipe is then formed by the concatenation of at least two sinusoidal ripples shown in fig. 1. The sine function r corresponding to the sine ripples is as follows:
r=R0+A×sin(N×θ),θ∈[0°,360°]
in the formula, R0The sine wave amplitude A is a natural number ranging from 0 to 8; in addition, the structure cannot meet central symmetry when the number N of the corrugations is positive odd, and the limited number N of the corrugations is positive even in order to be more beneficial to the stability of the deformation process. The utility model discloses a change each item geometric parameter and obtain different cross sectional shape, make up its energy-absorbing pipe that obtains the multilevel again.
The utility model discloses will explain with following two kinds of energy-absorbing pipes as an example:
example 1:
as the energy-absorbing pipe of a type 2 layers (the utility model discloses in be called one type energy-absorbing pipe) shown in fig. 2, outer sinusoidal ripple's trough is tangent with inlayer sinusoidal ripple's crest in two sinusoidal ripples of concatenation on its cross section, and two sinusoidal ripples correspond sinusoidal function's amplitude A, ripple number N is the same respectively, and basic nominal radius R is the same0In contrast, in this embodiment, the substantially nominal radius R of the outer tube is maintained0For a constant value of 25mm, the value of the basic nominal radius of the inner layer pipe is changed to ensure that the wave troughs of the sinusoidal corrugations on the section of the outer layer pipe are tangent to the wave crests of the sinusoidal corrugations on the section of the inner layer pipe. Wherein, the length L of the tube in this embodiment is 100 mm.
Example 2:
fig. 3 shows another type of energy-absorbing tube structure with 2 layers (referred to as "class-two energy-absorbing tube" in the present invention), in which the peaks and troughs of two sinusoidal corrugations spliced on the cross section are directly opposite to each other, and the amplitudes a, the number N, and the basic nominal radii R of the sinusoidal functions corresponding to the two sinusoidal corrugations are equal to each other0Are respectively the same.
Simulation experiment:
taking the amplitude A as 1mm and the corrugation number N as 6 as examples, the bottom end of the thin-wall pipe is fixedly restrained, and the top end of the thin-wall pipe is axially compressed by a rigid plate with a uniform speed of 3 m/s. As shown in fig. 4, the force-displacement curve of the single-layer transverse sinusoidal corrugated pipe and the two types of double-layer transverse sinusoidal corrugated pipes shows that the impact force of the double-layer transverse sinusoidal corrugated pipe is improved as a whole, which results in an improved average force. And compared with twice of the impact force of the single-layer pipe, the initial peak force of the two types of double-layer transverse sine corrugated pipes is not greatly increased. Thus, as shown in fig. 5, the specific energy absorption SEA of the double-layer transverse sine bellows structure is significantly higher than that of the single-layer transverse sine bellows, and it can be seen that the two-layer transverse sine bellows has the highest specific energy absorption.
As shown in fig. 6 and 7, the deformation modes of the single-layer tube and the double-layer tube in the compression process are respectively shown, and it can be seen from the drawings that both the hierarchical tube and the single-layer tube generate a relatively stable axisymmetric deformation mode, the hierarchical tube generates more folds in the compression process, and the hierarchical tube can absorb more energy in the deformation process due to the improvement of the rigidity of the hierarchical structure and the interaction between the tube walls.
As shown in fig. 8a and 8b of fig. 8, in order to solve the problem that the structure generates a large peak force in the initial stage in practical application, the present invention adds an inducing structure on the basis of the above structure to reduce the damage of the initial peak force. As shown in fig. 8a, a notch is formed at the top end of the outermost pipe wall, and in the present embodiment, the notch is located at the peak position of the outermost pipe wall, and a square groove is not cut along the axial direction at the intersection with the inner pipe, and the number of notches can be empirically obtained as the number of corrugations N. In other possible embodiments, it is desirable that the location of the cut-out is offset from the location of the juncture of the outermost tube wall with the adjacent inner tube wall. As shown in fig. 8b in fig. 8, the outermost pipe wall of the energy absorbing pipe is provided with openings, in this embodiment, the positions of the openings are located at the wave crests of the outermost pipe wall, that is, the positions of the outermost pipe wall, which are not intersected with the inner pipe, are provided with square openings, circular openings, and the like, which are axially uniform, and if the side length of each square opening is 10mm or the diameter of each circular opening is 10mm, the number of the axial openings is [1,5 ]. In other possible embodiments, it is desirable that the locations of the openings are offset from the locations of the junctions of the outermost tube walls with the adjacent inner tube walls.
It is emphasized that the examples described herein are illustrative and not restrictive, and thus the invention is not limited to the examples described herein, but rather is intended to cover all modifications, alterations, and equivalents falling within the spirit and scope of the invention as defined by the appended claims.
Claims (7)
1. The utility model provides a multilevel energy-absorbing pipe which characterized in that: the energy-absorbing pipe comprises two-layer pipeline wall concatenation at least, the energy-absorbing pipe includes the one-level cavity pipeline that encloses by inner pipe wall and a plurality of second grade cavity pipelines that adjacent two-layer pipeline wall concatenation formed, second grade cavity pipeline arranges one-level cavity pipeline is all around.
2. The energy absorbing tube of claim 1, wherein: the cross section of the energy-absorbing pipe is in a splicing shape of n sine waves, and n is the level number of the energy-absorbing pipe.
3. The energy absorbing tube of claim 2, wherein: the wave troughs of the outer sine waves in every two sine waves spliced on the cross section are tangent to the wave crests of the inner sine waves, the amplitudes and the wave numbers of the corresponding sine functions of the two sine waves are respectively the same, and the basic nominal radiuses are different.
4. The energy absorbing tube of claim 2, wherein: the energy absorption pipe is a double-layer energy absorption pipe, the wave crests and the wave troughs of two sine waves spliced on the cross section are opposite one by one, and the amplitude, the wave number and the basic nominal radius of sine functions corresponding to the two sine waves are respectively the same.
5. The energy absorbing tube of claim 2, wherein: the sine function r corresponding to the sine ripple is as follows:
r=R0+A×sin(N×θ),θ∈[0°,360°]
in the formula, R0The value of the amplitude A of the sine wave is a natural number ranging from 0 to 8, N is the wave number, and the wave number N is a positive even number.
6. The energy absorbing tube of claim 1, wherein: the number n of the layers of the energy absorption pipe is 2.
7. The energy absorbing tube of claim 1, wherein: the energy absorption pipe is characterized in that the outermost layer pipe wall of the energy absorption pipe is provided with an opening or the top end of the outermost layer pipe wall is provided with a cutting groove downwards, and the positions of the opening and the cutting groove are staggered with the joint position of the outermost layer pipe wall and the adjacent inner layer pipe wall.
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CN202020595000.1U CN212407410U (en) | 2020-04-20 | 2020-04-20 | Multilevel energy absorption pipe |
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CN202020595000.1U CN212407410U (en) | 2020-04-20 | 2020-04-20 | Multilevel energy absorption pipe |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111891169A (en) * | 2020-08-12 | 2020-11-06 | 中车株洲电力机车有限公司 | Rail transit car coupler buffering energy-absorbing device |
CN113775682A (en) * | 2021-11-12 | 2021-12-10 | 太原理工大学 | Adjustable circular tube energy absorption/storage mechanism based on paper-cut structure |
-
2020
- 2020-04-20 CN CN202020595000.1U patent/CN212407410U/en not_active Withdrawn - After Issue
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111891169A (en) * | 2020-08-12 | 2020-11-06 | 中车株洲电力机车有限公司 | Rail transit car coupler buffering energy-absorbing device |
CN113775682A (en) * | 2021-11-12 | 2021-12-10 | 太原理工大学 | Adjustable circular tube energy absorption/storage mechanism based on paper-cut structure |
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