A Tear-Bending Energy Absorption Structure for Metal Round Tubes

Abstract

The present invention discloses a tearing and bending energy absorption structure for a metal round tube, which relates to the technical field of passive safety protection. It includes an external guide cover and an internal expansion sleeve. The external guide cover is of a cylindrical structure, and a guiding surface is provided at one end inside the external guide cover. A transition surface is provided between the larger-diameter end and the smaller-diameter end of the internal expansion sleeve, and the smaller-diameter end of the internal expansion sleeve is used to connect with one end of the metal round tube. The internal expansion sleeve is arranged inside the external guide cover, and the smaller-diameter end of the internal expansion sleeve extends out of the external guide cover from the end where the guiding surface is provided, and there is a gap between the outer wall of the internal expansion sleeve and the inner wall of the external guide cover. The external guide cover structure is used to realize the change of the curling structure direction from upward to downward extension and bending, so as to ensure that the upper deformation space stroke is not interfered, and the effective stroke can reach 100%. At the same time, the energy absorption capacity of the structure can also be greatly improved. The surfaces of both the internal expansion sleeve and the external guide cover are treated with arc transitions to ensure that the material can extend and bend smoothly after deformation.

Description

Technical Field

[0001] The present invention relates to the technical field of passive safety protection, and particularly relates to a tearing and bending energy absorption structure of a metal round tube. Background Art

[0002] Energy absorption structures are widely used in energy dissipation systems. For example, the bulging energy absorption device in the coupler buffer device used to improve the crashworthiness of the connection part of a train. The crashworthiness of the structure mainly depends on the crashworthiness of the energy absorption structure in the energy dissipation system. Therefore, the research on the crashworthiness of the energy absorption structure is the main consideration factor in passive safety protection technology. Among energy absorption structures, metal thin-walled structures are the most widely used. There are various types of metal thin-walled structures, such as round tubes, square tubes, square tubes or round tubes filled with honeycomb aluminum or foam aluminum. At the same time, there are also various forms of energy dissipation, such as axial crushing, expansion, necking, flipping, tearing, etc. The deformation mode of the energy absorption structure determines its large-deformation mechanical properties and the ability to absorb impact kinetic energy. Different factors such as impact velocity, structural geometric parameters, strain rate effect, inertial effect, and initial defects have obvious effects on the deformation mode of the structure.

[0003] Such as Figure 1 As shown, after the existing bulging-tearing energy absorption structure generates tearing deformation, the residual structure will naturally curl upward outside the metal thin-walled structure, forming a residual curling structure. This deformation mode will occupy the effective deformation space of the structure and reduce the crushing force of the structure, thus greatly restricting the energy absorption capacity of the structure. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a tearing and bending energy absorption structure of a metal round tube to solve the problem that the residual deformation structure interferes with the deformation space, resulting in insufficient energy absorption and limited deformation stroke.

[0005] To achieve the above object, the present invention provides the following solution:

[0006] The present invention provides a tearing and bending energy absorption structure of a metal round tube, including an external guide cover and an internal expansion sleeve; the external guide cover is a bottomless and lidless cylindrical structure, and a guiding surface is provided at one end inside the external guide cover; a transition surface is provided between the larger diameter end and the smaller diameter end of the internal expansion sleeve, and the smaller diameter end of the internal expansion sleeve is used to connect with one end of the metal round tube; the internal expansion sleeve is arranged inside the external guide cover, the smaller diameter end of the internal expansion sleeve extends out of the external guide cover from the end where the guiding surface is provided on the external guide cover, and there is a spaced space between the outer wall of the internal expansion sleeve and the inner wall of the external guide cover.

[0007] Optionally, it further includes a connecting plate, and an outer limiting groove for limiting the external guide cover and an inner limiting groove for limiting the internal expansion sleeve are provided on the connecting plate.

[0008] Optionally, the internal expansion sleeve is of a hollow structure.

[0009] The present invention has achieved the following technical effects compared with the prior art:

[0010] 1. In the tearing and bending energy absorption structure of the metal round tube in the present invention, the external guide cover structure can be used to change the curling structure direction from upward to downward extension and bending, so as to ensure that the upper deformation space stroke is not interfered, and the effective stroke can reach 100%.

[0011] 2. The bending deformation mode after the metal round tube is torn can significantly improve the crushing force of the structure, thereby increasing the impact energy absorption capacity of the structure.

[0012] 3. The surfaces of the internal expansion sleeve and the external guide cover are both processed with arc transitions to ensure that the material can extend and bend smoothly after deformation. Description of the Drawings

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0014] Figure 1 FIG. is a schematic structural diagram of an existing bulging-tearing energy absorption structure after tearing deformation;

[0015] Figure 2 FIG. is a schematic structural diagram of the tearing and bending energy absorption structure of the metal round tube of the present invention;

[0016] Figure 3 FIG. is a schematic structural diagram of the metal round tube of the tearing and bending energy absorption structure of the present invention after the metal tube expands and tears;

[0017] Figure 4 FIG. is a schematic cross-sectional structural diagram of the external guide cover in the tearing and bending energy absorption structure of the metal round tube of the present invention;

[0018] Figure 5 FIG. is a schematic structural diagram of the internal expansion sleeve in the tearing and bending energy absorption structure of the metal round tube of the present invention.

[0019] Description of the reference numerals: 1, metal round tube; 2, internal expansion sleeve; 3, external guide cover. Detailed Embodiments

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0021] As Figures 2 to 5 shown, this embodiment provides a tearing and bending energy absorption structure for a metal round tube, including an external guide cover 3 and an internal expansion sleeve 2; the external guide cover 3 is a cylindrical structure without a bottom and a cover, and a guiding surface is provided at one end inside the external guide cover 3; a transition surface is provided between the larger diameter end and the smaller diameter end of the internal expansion sleeve 2, and the smaller diameter end of the internal expansion sleeve is used to connect with one end of the metal round tube 1; the internal expansion sleeve 2 is arranged inside the external guide cover 3, and the smaller diameter end of the internal expansion sleeve 2 extends from the end of the external guide cover 3 with the guiding surface to the outside of the external guide cover 3, and there is a spaced space between the outer wall of the internal expansion sleeve 2 and the inner wall of the external guide cover 3.

[0022] In this specific embodiment, it further includes a connecting plate, and an outer limiting groove for limiting the external guide cover 3 and an inner limiting groove for limiting the internal expansion sleeve 2 are provided on the connecting plate. The connecting plate makes the external guide cover 3 and the internal expansion sleeve 2 keep coaxially arranged, and avoids the relative position between the external guide cover 3 and the internal expansion sleeve 2 during the tearing process of the metal round tube 1, resulting in the offset of the deformed part of the metal round tube 1 and affecting the energy absorption effect.

[0023] In this embodiment, the internal expansion sleeve 2 is a hollow structure. While reducing the overall weight of the energy absorption structure, it improves the heat dissipation capacity of the internal expansion sleeve 2, so that the metal round tube 1 and the internal expansion sleeve 2 maintain sufficient structural strength.

[0024] Under the action of the internal expansion sleeve 2, the metal round tube 1 first undergoes radial expansion plastic deformation, and then undergoes tearing and curling deformation at the end of the expansion sleeve.

[0025] It should be noted that for those skilled in the art, obviously the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, in any aspect, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes falling within the meaning and scope of the equivalent elements of the claims in the present invention, and any reference signs in the claims should not be regarded as limiting the claimed rights.

[0026] In this specification, specific examples are used to illustrate the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A tearing and bending energy absorption structure for a metal circular tube, characterized in that, It includes an external guide cover and an internal expansion sleeve; the external guide cover is a cylindrical structure without a bottom and a cover, and a guiding surface is provided at one end inside the external guide cover; a transition surface is provided between the larger-diameter end and the smaller-diameter end of the internal expansion sleeve, and the smaller-diameter end of the internal expansion sleeve is used to connect to one end of a metal round tube; the internal expansion sleeve is arranged inside the external guide cover, the smaller-diameter end of the internal expansion sleeve extends out of the external guide cover from the end where the guiding surface is provided, and there is a spaced space between the outer wall of the internal expansion sleeve and the inner wall of the external guide cover; Under the action of the internal expansion sleeve, the metal round tube first undergoes radial expansion plastic deformation, and then undergoes tearing and curling deformation at the end of the internal expansion sleeve; It further includes a connecting plate, and an outer limiting groove for limiting the external guide cover and an inner limiting groove for limiting the internal expansion sleeve are provided on the connecting plate.

2. The tearing and bending energy absorption structure for a metal circular tube according to claim 1, characterized in that, The internal expansion sleeve is a hollow structure.

Images