A multi-stage jump buckling energy absorption structure

Abstract

The present invention belongs to the technical field of multi-stable structures, specifically a multi-stage jump buckling energy absorption structure. This multi-stage jump buckling energy absorption structure is a multi-layer, grid-like truncated cone structure, which is composed of a number of clockwise spiral conical twisted curved beams of the same shape and the same number of counterclockwise spiral conical twisted curved beams. These curved beams are staggered and connected to form a mesh structure; the entire grid-like truncated cone structure is divided into several layers from bottom to top, and two adjacent layers are separated by a circular plate, and the dividing plate is parallel to the bottom plate; when subjected to axial load, multi-stage jump buckling will occur in sequence. Each deformation of this structure can be adjusted, each form has high stability, the form change is extremely flexible, and elastic deformation can be restored; it can realize functions such as load detection, multi-stage energy absorption, multi-stage compression and multi-stage self-locking, and has application prospects in the fields of mechanical equipment design, aerospace, construction engineering, materials and transportation.

Description

Technical Field

[0001] The invention belongs to the technical field of multi-stable structures, and in particular relates to a multi-stage jump buckling energy absorption structure. Background Art

[0002] Jump buckling is common in multi-stable structures under load, that is, when a multi-stable structure changes from one stable state to another under the action of external force, the buckling transition phenomenon occurs, and the loading curve changes suddenly as the structure deforms. Structures and machines designed using this mechanical property can reduce redundant restraints and simplify mechanical structures, and can be used in the design of self-locking structures, supporting structures, and unfolding structures. Multi-stage jump buckling refers to the multi-stable phenomenon that a structure can undergo jump buckling again or multiple times after buckling has occurred, which can achieve richer and more complex functions and energy absorption effects.

[0003] The present invention provides an energy absorbing structure which can undergo multi-stage jump buckling behavior after being axially compressed. Summary of the invention

[0004] The object of the present invention is to provide a multi-stage jump buckling energy absorption structure which has different levels of response to different pressures and can recover elastic deformation.

[0005] The multi-stage jump buckling energy absorption structure provided by the present invention will undergo multi-stage jump buckling in sequence when subjected to pressure, such as Figure 1 , Figure 7 As shown, it is a multi-layer, grid-like truncated cone structure, which is specifically composed of a number of curved beams of the same shape rotating in a clockwise spiral cone shape and the same number of curved beams rotating in a counterclockwise spiral cone shape. These curved beams are interlaced and connected to each other to form a grid structure; the entire grid-like truncated cone structure is divided into several layers from bottom to top, and two adjacent layers are separated by a circular plate, and the dividing plate is parallel to the bottom plate.

[0006] The symmetry axis direction of the cone is called the axial direction, and the pressure applied in this direction is called the axial load. F , under axial load F Under the action, the structure undergoes axial compression deformation accordingly. In each state, the axial length of the structure has changed by a value of △ h The original length of the structure H The ratio of the axial strain ε ,Right now ε =value△ h / H .

[0007] In the present invention, the cross section of the curved beam is circular, square, or other shapes. The structure designed in the present invention is dimensionless, so the size range given is only for reference and can be expanded as appropriate in actual production if necessary.

[0008] Its cross-sectional area is 1 to 16 mm 2 .

[0009] In the present invention, the number of the curved beams (clockwise spiral cone or counterclockwise spiral cone) is generally 12 to 20, which is specifically determined according to the size of the upper and lower bottom circular plates of the truncated cone structure and the number of levels of the structure;

[0010] Usually, the number of layers of the overall structure is 2 to 5. Figure 1 There are 2 floors in the middle. Figure 7 The middle is 3 layers;

[0011] Usually, the bottom circular plate of the overall structure has a diameter of 20 to 500 mm, and the top circular plate has a diameter of 5 to 300 mm;

[0012] Usually, in the overall structure, the height of each layer is the same.

[0013] In the present invention, the curved beam and the dividing plate are usually made of materials with good elasticity and toughness, such as TPU, TPU95A, nylon, etc.

[0014] The multi-stage jump buckling energy absorption structure designed in the present invention can be prepared by 3D printing additive manufacturing, or by various methods such as splicing and bonding.

[0015] For example, the drawings are printed using 3D printing additive manufacturing, with water-soluble supports. After printing, they are immersed in water, the support materials are removed, and then dried. Multi-level jump buckling can be achieved by applying pressure.

[0016] The multi-stage jump buckling energy absorption structure designed by the present invention has the following characteristics:

[0017] (1) Pressure can produce a variety of deformation forms, and each deformation can be controlled;

[0018] (2) This structure is a multi-stable structure, and each form has high stability;

[0019] (3) The number of stages is adjustable, the order of multi-stage jump buckling is adjustable, and the shape change is extremely flexible.

[0020] The structure with multi-stage jump buckling mechanical characteristics proposed in the present invention has different levels of response to different ballasts, and elastic deformation can be recovered. Through the design, the following functions can be realized: load detection, multi-stage energy absorption, multi-stage compression and multi-stage self-locking, etc., and it has application prospects in the fields of mechanical equipment design, aerospace, construction engineering, materials and transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the secondary energy absorption structure (divided into side view, top view, and three-dimensional view).

[0022] Figure 2 This is the initial diagram of the axial compressive load of the secondary energy absorbing structure in Example 1.

[0023] Figure 3 This is the first-stage energy absorption deformation diagram of the secondary energy absorption structure of Example 1 subjected to axial compressive load.

[0024] Figure 4 This is the second-stage energy absorption deformation diagram of the secondary energy absorption structure of Example 1 subjected to axial compressive load.

[0025] Figure 5 This is the axial load-axial strain diagram of the secondary energy absorption structure of Example 1.

[0026] Figure 6 This is the strain energy-axial strain diagram of the secondary energy absorption structure of Example 1.

[0027] Figure 7 It is a schematic diagram of the three-level energy absorption structure (divided into side view, top view, and three-dimensional view).

[0028] Figure 8 This is the initial diagram of the axial compressive load diagram of the three-stage energy absorption structure in Example 2.

[0029] Fig. 9 This is the first-stage energy absorption deformation diagram of the three-stage energy absorption structure of Example 2 subjected to axial compressive load.

[0030] Fig.10 This is the second-stage energy absorption deformation diagram of the three-stage energy absorption structure of Example 2 subjected to axial compressive load.

[0031] Fig.11 This is the third-stage energy absorption deformation diagram of the three-stage energy absorption structure of Example 2 subjected to axial compressive load.

[0032] Fig.12 This is the axial load-axial strain diagram of the three-level energy absorption structure in Example 2.

[0033] Fig.13 This is the strain energy-axial strain diagram of the three-level energy absorption structure in Example 2. DETAILED DESCRIPTION

[0034] Embodiment 1:

[0035] Printed using a 3D printer, the materials used are TPU95A and PLA, and the water-soluble support material used is PVA.

[0036] The designed multi-stage jump buckling energy absorption structure is as follows Figure 2As shown, its structure has two layers, each plate is 2mm thick, printed with PLA material, and the radii of the disks from top to bottom are 12mm, 32mm and 52mm respectively; there are 8 clockwise and counterclockwise spiral conical beams in each layer, with a pitch of 160mm, 0.25 turns, and evenly distributed starting angles. The cross-sectional shape is a circle with a radius of 1mm. The upper end radii of the upper and lower layers of spiral cones are 10mm and 30mm respectively, and they are printed with TPU material.

[0037] like Figure 3 and Figure 4 As shown in Figure 2, under axial compressive load, the structure undergoes two jump bucklings in sequence. Figure 5 As shown, the horizontal axis is the axial strain ε , the longitudinal axis is the applied axial load F , it can be seen that when the axial pressure is loaded, the structure deforms and there are two "peaks" in the load process. Figure 6 The horizontal axis is the axial strain ε , the vertical axis is the strain energy obtained after the structure absorbs energy E , the structure can continue to absorb energy during deformation.

[0038] Embodiment 2:

[0039] Printed using a 3D printer, the materials used are TPU95A and PLA, and the water-soluble support material used is PVA.

[0040] The designed multi-stage jump buckling energy absorption structure is as follows Figure 8 As shown, its structure has three layers, each plate is 2mm thick, printed with PLA material, and the radii of the disks from top to bottom are 12mm, 32mm, 52mm and 72mm respectively; there are 8 clockwise and counterclockwise spiral conical beams in each layer, with a pitch of 160mm, 0.25 turns, and uniformly distributed starting angles. The cross-sectional shape is a circle with a radius of 1mm, and the upper and lower layers of spiral cones have radii of 10mm, 30mm and 50mm respectively, which are printed with TPU material.

[0041] like Fig. 9 , Fig.10 and Fig.11 As shown in Figure 2, under axial compressive load, the structure undergoes three jump bucklings in sequence. Fig.12 As shown in Figure 1, when the axial pressure is applied, the structure deforms and there are three "peaks" in the load process. Fig.13 As shown, the structure can continuously absorb energy during the deformation process, and the energy absorption effect of the structure in Example 2 is better than that in Example 1.

Claims

1. A multi-stage jump buckling energy absorption structure, characterized in that: It is a multi-layer, grid-like truncated cone structure, consisting of a number of clockwise spiral conical twisted curved beams of the same shape and the same number of counterclockwise spiral conical twisted curved beams. These curved beams are set at the edges of each layer of plates, and these curved beams are evenly arranged and interlaced with each other to form a grid structure; the entire grid-like truncated cone structure is divided into several layers from bottom to top, and two adjacent layers are separated by a circular partition plate, and the partition plate is parallel to the bottom layer; when subjected to axial load, multiple levels of jump buckling will occur in sequence.

2. The multi-stage jump buckling energy absorption structure according to claim 1 is characterized in that: The cross section of the curved beam is circular or square, and its cross section area is 1 to 16 mm 2 .

3. The multi-stage jump buckling energy absorption structure according to claim 1 is characterized in that: The number of the clockwise spiral conical twisted curved beams or the counterclockwise spiral conical twisted curved beams is 12 to 20, which is specifically determined according to the size of the upper and lower bottom circular plates of the truncated cone structure and the number of levels of the structure.

4. The multi-stage jump buckling energy absorption structure according to claim 1, characterized in that: The overall structure has 2 to 5 layers.

5. The multi-stage jump buckling energy absorption structure according to claim 1, characterized in that: The diameter of the bottom circular plate is 20 to 500 mm, and the diameter of the top circular plate is 5 to 300 mm.

6. The multi-stage jump buckling energy absorption structure according to claim 1, characterized in that: The height of each floor is the same.

7. The multi-stage jump buckling energy absorption structure according to claim 1 is characterized in that: The curved beam and the dividing plate are made of a material with good elasticity and toughness, selected from TPU or nylon.

8. A method for preparing a multi-stage jump buckling energy absorption structure according to any one of claims 1 to 7, characterized in that: Use 3D printing additive manufacturing, or splicing and bonding methods.

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