Repeatable energy absorption structure formed by compounding elastic material and elastoplastic material

Abstract

The invention relates to the field of buffering energy absorption structures, in particular to a repeatable energy absorption structure formed by compounding an elastic material and an elastic plastic material, which comprises an energy absorption unit made of the elastic plastic material, the supporting unit is made of an elastic material; the supporting units are arranged between the energy absorption units and used for providing anti-deformation force when the energy absorption units absorb energy and providing restoring force after the energy absorption units absorb the energy. The elastic material is filled with the elastic plastic material, so that the area of a hysteretic loop of a force-displacement curve can be increased on the premise that the recovery rate is not reduced. Compared with a traditional repeatable energy absorption structure for increasing the hysteretic loop area through the friction effect, the elastic material and elastoplastic material composite structure increases the hysteretic loop area through the plasticity generated by repeated deformation of the elastoplastic material. The energy absorption structure can achieve repeated energy absorption, and the problem that most of existing energy absorption structures made of elastoplastic materials cannot achieve repeated energy absorption is solved.

Description

Technical Field

[0001] The invention relates to the field of buffering and energy absorption, and in particular to a repeatable energy absorption structure composed of an elastic material and an elastoplastic material. Background Art

[0002] Elastic materials are widely used in energy absorption scenarios such as packaging engineering because they have good recovery characteristics and have a rebound force equal to the loading force after being compressed. Porous materials made of elastoplastic materials, such as honeycomb structures, are light, strong, and have high energy absorption levels, and are often used in the field of collision protection. However, for elastic materials, their higher rebound force, on the one hand, reduces the energy absorption area of ​​the hysteresis loop, and on the other hand, causes certain damage to the protective structure. For elastoplastic materials, the irreversible nature of elastoplastic materials determines that the energy absorption structure made of elastoplastic materials can only achieve single energy absorption, but not multiple energy absorption. In actual scenarios, for example, under the action of a strong earthquake, the displacement of the building exceeds the reserved distance of the seismic trench and will hit the foundation structure. If a crash pad is to be set up to protect the building from multiple impacts, and has a smaller rebound force to protect the building and the foundation structure, elastic materials or elastoplastic materials alone cannot achieve this goal. If a composite structure model combining elastic material and elastoplastic material is established, the resilience of the elastic material just makes the compressed elastoplastic material recover, and the overall reaction force of the composite structure is small. The elastoplastic material improves the overall stiffness of the structure, and the plasticity of the elastoplastic material can increase the area of ​​the hysteresis loop.

[0003] At the same time, most of the current repeatable energy absorption structures rely on springs and friction damping, and they are highly dependent on the direction of external force compression. They are required to be part of the overall structure and are often used for earthquake protection of building steel structures. In the collision field, the impactor and the anti-collision pad are separated, so they are not suitable for the collision energy absorption field. Summary of the invention

[0004] The technical problem to be solved by the present invention is to propose a repeatable energy absorption structure composed of an elastic material and an elastic-plastic material, so as to solve the problem that the elastic-plastic porous material in the field of collision protection cannot realize repeated energy absorption and the problem that some elastic materials have too high resilience. The elastic material and the elastic-plastic material are compounded, and the elastic-plastic material is embedded in the elastic material. The structure composed of the elastic material and the elastic-plastic material has a larger hysteresis loop energy absorption area and a lower resilience.

[0005] In order to solve the above technical problems, the technical solution of the present invention is:

[0006] A repeatable energy absorbing structure composed of an elastic material and an elastoplastic material, comprising:

[0007] An energy absorbing unit made of elastic-plastic material;

[0008] A support unit made of elastic material; the support unit is filled between the energy absorbing units to provide anti-deformation force when the energy absorbing unit absorbs energy and to provide restoring force after the energy absorbing unit absorbs energy.

[0009] The present invention is a repeatable energy-absorbing structure composed of an elastic material and an elastoplastic material, and is coupled by embedding the elastoplastic material and the elastic material into each other. The plasticity of the elastoplastic material can be used as a source of energy absorption, and the restoring force of the elastic material enables the elastoplastic material to return to its original state. Through the support of the elastic material, the hysteresis loop area of ​​the force-displacement curve of the elastoplastic material under the reciprocating compression can be increased, thereby improving the energy absorption capacity. Among the elastic materials, the elastic material has a higher compression recovery rate and at the same time has a higher resilience when unloading after compression. The Young's modulus of the elastoplastic material is relatively large, and the irreversible deformation is relatively large when unloading after compression. At the same time, the elastoplastic material has a good repeated deformation ability.

[0010] After the elastic material is processed by laser cutting and the elastic-plastic material is processed by a mold, the elastic material and the elastic-plastic material are bonded by a strong soft adhesive, and no relative sliding occurs at the bonding interface.

[0011] The energy absorbing unit is an arc corrugated plate.

[0012] The arc corrugated plate is formed by upper and lower mirrored arc segments connected one by one through two end points; the radius r of the arc segment is selected to be 32 mm, r is determined according to the specific structural length requirements, and the central angle θ of the arc segment is in the range of 60°-120°. Within this angle range, it can be ensured that the plastic area of ​​the corrugated plate is more distributed and the plastic area length is longer.

[0013] The two adjacent arc corrugated plates are topologically formed into an integral structure by upper and lower mirror images. Compared with other configurations, after the corrugated plate integral structure is compounded with elastic material, the plastic hinges can be evenly distributed, achieving repeated energy absorption without fatigue fracture.

[0014] The energy absorbing structure is a honeycomb structure obtained by mirroring the corrugated plate, and the overall structure is formed by staggered stacking of the corrugated plate and the elastic material. At the same time, it can also be made into a structure composed of elastic-plastic materials in advance by 3D printing, and filled with elastic block materials to obtain the overall structure, and the corrugated plate structure mixed with elastic materials and elastic-plastic materials can be used to obtain the overall structure by translating the corrugated plate or mirroring the corrugated plate.

[0015] The elastic material constituting the supporting unit is rubber material, polyurethane, foam or sponge.

[0016] The supporting unit is a spring.

[0017] The elastic material constituting the energy absorbing unit is a metal material or a plastic.

[0018] The metal material constituting the energy absorbing unit is steel, aluminum or copper.

[0019] The beneficial effects of the present invention are:

[0020] 1. The present invention proposes a repeatable energy absorption structure composed of an elastic material and an elastoplastic material, which can achieve multiple repeatable energy absorption, solving the problem that most current elastoplastic material energy absorption structures cannot achieve multiple energy absorption.

[0021] 2. The present invention proposes a repeatable energy-absorbing structure composed of an elastic material and an elastoplastic material, which can absorb energy by relying on the elastic-plastic properties of the elastoplastic material, and at the same time rely on the resilience of the elastic material to enable the structure to recover with a lower resilience.

[0022] 3. The present invention proposes a repeatable energy absorption structure composed of an elastic material and an elastic-plastic material, wherein the elastic material is cut into the shape of a support unit, the elastic-plastic material is molded into the shape of an energy absorption unit, and the elastic material and the elastic-plastic material are bonded together. Compared with the traditional energy absorption structure and the friction damping spring self-reset structure, the construction method is simple, fast and low-cost.

[0023] 4. The present invention proposes a repeatable energy absorption structure composed of elastic material and elastoplastic material, which is not sensitive to the direction of collision protection, that is, it can resist impacts in multiple directions and achieve repeatable energy absorption. Compared with the traditional self-resetting damper structure that is sensitive to the compression direction, the repeatable energy absorption structure composed of elastic elastoplastic material can be applied to more energy absorption scenarios and has a wider range of application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A top view of a repeatable energy absorbing structure made of a composite of elastic material and elastoplastic material according to an embodiment of the present invention;

[0025] Figure 2 The manufacturing process of the embodiment of the present invention;

[0026] Figure 3 A plan view of the arc corrugated plate structure according to an embodiment of the present invention;

[0027] Figure 4 The reciprocating compression stress-strain curve of the structure capable of repeatedly absorbing energy, which is a composite of elastic material and elastoplastic material, and the reciprocating compression stress-strain curve of a pure elastic material according to an embodiment of the present invention;

[0028] Figure 5Schematic diagrams of repeatable energy absorption structures of energy absorption units of other configurations, wherein (a) is a composite energy absorption structure of regular hexagonal honeycomb elastic-plastic materials; (b) is a composite energy absorption structure of corrugated plate translational elastic-plastic materials; (c) is a curved beam structure of mixed elastic and elastic-plastic materials; (d) is a composite energy absorption structure of rotational chiral integrated elastic-plastic materials; (e) is a composite energy absorption structure of chiral integrated elastic-plastic materials; (f) is a composite energy absorption structure of anti-chiral integrated elastic-plastic materials; (g) is a composite energy absorption structure of concave hexagonal honeycomb elastic-plastic materials; (h) is a composite energy absorption structure of brick-type elastic-plastic materials; (i) is a hexagonal honeycomb structure of mixed elastic and elastic-plastic materials;

[0029] Figure 6 Schematic diagram of a structure formed by staggered stacking of elastic-plastic corrugated plates and elastic materials, wherein the structures include: (a) a composite energy-absorbing structure of elastic-plastic materials of a corrugated plate translation type, (b) a composite energy-absorbing structure of elastic-plastic materials of a regular hexagonal honeycomb, (c) a composite energy-absorbing structure of elastic-plastic materials of a brick type, and (d) a composite energy-absorbing structure of elastic-plastic materials of a concave hexagonal honeycomb;

[0030] Figure 7 A manufacturing flow chart for filling elastic blocks for an integrated elastic-plastic material structure, wherein the structure includes: (a) a composite energy absorbing structure of a rotationally chiral integrated elastic-plastic material, (b) a composite energy absorbing structure of a chiral integrated elastic-plastic material and a composite energy absorbing structure of an anti-chiral integrated elastic-plastic material;

[0031] Figure 8 A schematic diagram of preparing a corrugated plate of mixed elastic material and elastic-plastic material, wherein the structure includes: a hexagonal honeycomb structure of mixed elastic material and elastic-plastic material and a curved beam structure of mixed elastic material and elastic-plastic material;

[0032] Fig. 9 A schematic diagram of a scheme in which a spring is used as an elastic material;

[0033] In the figure, 1-support unit; 2-laser cutting; 3-straight plate; 4-mold; 5-energy absorption unit; 6-spring. DETAILED DESCRIPTION

[0034] The following is a further detailed description of the embodiments of the present invention from the perspective of design, manufacturing process and energy absorption effect in conjunction with the accompanying drawings.

[0035] A repeatable energy-absorbing structure made of elastic and elastoplastic materials, such as Figure 1 As shown, including:

[0036] An energy absorbing unit 5 made of elastic-plastic material;

[0037] The support unit 1 is made of elastic material; the support unit 1 is arranged between the energy absorbing units 5 by filling or embedding, etc., and is used to provide anti-deformation force when the energy absorbing unit 1 absorbs energy, and provide restoring force after the energy absorbing unit 1 absorbs energy.

[0038] In one embodiment, the elastic material of the support unit 1 is a polyurethane material with ideal elasticity.

[0039] In one embodiment, the elastic-plastic material of the energy absorbing unit 5 is Q235 steel.

[0040] like Figure 1 As shown. The specific shape of the elastic-plastic material of the energy absorbing unit 5 can be any form, but different shapes will produce different energy absorbing effects. In one embodiment, the present invention provides an energy absorbing unit 5 in the form of a circular arc corrugated plate. It can be obtained by the basic parameters of the central angle θ of the circular arc segment of the corrugated plate, the radius r of the circular arc segment, the thickness t of the circular arc corrugated plate, and the number n of the circular arc segments. The length of the circular arc corrugated plate is L, and the height is H, which can be calculated according to the following formula.

[0041]

[0042]

[0043] The elastic material, in order to fill the elastic-plastic material, needs to be cut into a shape determined by the shape of the elastic-plastic material. The elastic material is formed into a specific shape after laser cutting, and combined with the elastic-plastic material, the elastic material can just cover the arc corrugated plate elastic-plastic material.

[0044] A structure that can absorb energy repeatedly and is composed of elastic and elastoplastic materials. Its characteristics are that the arc corrugated plate elastoplastic material is embedded in the elastic material, and the elastic material just covers the elastoplastic material. The overall size of the composite structure can be defined by length L0, width D0, and height H0, which can be calculated according to the following formula.

[0045] The number of corrugated plates is denoted by k.

[0046]

[0047]

[0048] The structure that can absorb energy repeatedly is composed of elastic material and elastoplastic material. The resilience of the elastic material just makes the elastoplastic material recover after compression, and the overall reaction force of the composite structure is small. The elastoplastic material improves the overall stiffness of the structure, and the elastoplasticity of the elastoplastic material can increase the area of ​​the hysteresis loop.

[0049] In one embodiment, the radius r of the arc segment of the arc corrugated plate is 32 mm, the center angle θ of the arc segment is 110°, and the upper and lower mirrored arc segments are connected one by one through two end points to form a corrugated plate. Figure 3 In the plan view of the corrugated plate, there are 6 arc segments, the total length L of the arc segments is 314 mm, and the total height H is 36 mm. The thickness of the arc corrugated plate is 5 mm. The arc corrugated plate is topologically formed into an overall structure through upper and lower mirroring, such as Figure 1 As shown in FIG. 1 , the overall length L0 of the structure is 314 mm, and the overall height H0 is 216 mm. The elastic material just covers the elastic-plastic material, and the outer contour of the elastic material just covers all the elastic-plastic material.

[0050] In the manufacturing process: after the specific parameters of the arc corrugated plate are determined, the elastic material is laser cut according to the parameters and position relationship of the arc corrugated plate. At the same time, a straight plate 3 made of Q235 material is molded into an arc corrugated plate through a mold 4. Then, Figure 2 As shown, the elastic material and the arc corrugated plate are combined in pairs and bonded together by strong glue. The shear strength of the strong glue reaches more than 20MPa to prevent debonding at the interface.

[0051] In terms of the manufacturing process: the energy absorbing unit can be pressed into the supporting unit by molding, such as pressing a stainless steel corrugated plate into a foam material.

[0052] In terms of energy absorption capacity: Figure 4 The stress-strain curve of the reciprocating compression of the structure composed of elastic-elastoplastic materials and the stress-strain curve of the reciprocating compression of pure elastic materials are shown. It can be seen that the loading curve and unloading curve of the pure elastic material are overlapped, and it cannot absorb energy, while the hysteresis loop area of ​​the structure composed of elastic-elastoplastic materials and repeatable energy absorption is larger. The structure composed of pure elastic material and Q235 corrugated plate can absorb 60KJ of energy. At the same time, the recovery rate of the structure composed of elastic-elastoplastic materials and repeatable energy absorption reaches 95%. The presence of elastic-plastic materials does not reduce the recovery rate of the material, but after reciprocating compression, it can absorb a large amount of energy.

[0053] Other possible configurations of the present invention

[0054] In the present invention, the arc corrugated plate is only a topological form of an elastic-plastic material, and the elastic-plastic material can be embedded in the elastic material in any form. Figure 5 Nine topological forms of elastic and elastoplastic materials are shown. Figure 5 (a) shows the composite energy-absorbing structure of regular hexagonal honeycomb elastic-plastic material. Figure 5 (b) A composite energy-absorbing structure of elastic-plastic materials with a corrugated plate translation type Figure 5(g) is a composite energy-absorbing structure of concave hexagonal honeycomb elastic-plastic material. Figure 5 (h) is a composite energy-absorbing structure of brick-type elastic-plastic materials. The formation methods of these four structures are similar to the elastic-plastic corrugated plate energy-absorbing structure mentioned above. They are all formed by staggered stacking of elastic-plastic corrugated plates and elastic materials to form an overall structure. Figure 6 Displayed in. Figure 6 In the invention, the corrugated plate is respectively stacked with a wave-shaped elastic material, a regular hexagonal block elastic material, a square elastic material, and a concave hexagonal block elastic material. Figure 5 (d) is a composite energy-absorbing structure of rotational chiral integrated elastic-plastic materials, Figure 5 (e) is a composite energy-absorbing structure of chiral integrated elastic-plastic materials, Figure 5 (f) is a composite energy-absorbing structure of an anti-chiral integrated elastic-plastic material. These three structures are first manufactured through integration to form an overall structure of the elastic-plastic material, which can be done by 3D printing or welding, and then filled with an elastic block material. The shape of the elastic block material is consistent with the hole shape of the elastic-plastic material. The process is shown in Figure 7 middle. Figure 5 (i) is a hexagonal honeycomb structure of mixed elastic material and elastoplastic material, Figure 5 (c) is a curved beam structure made of mixed elastic and elastoplastic materials. Figure 8 As shown in the figure, these two structures are made of corrugated plates made of mixed elastic materials and elastoplastic materials, and the overall structure is formed by replication and mirroring. Among them, the elastic material can also be replaced by a spring. Fig. 9 A case in which a spring 6 replaces an elastic block material is given. Other similar structures in which elastic-plastic materials are embedded in elastic materials or elastic materials and elastic-plastic materials are combined are all within the protection scope of the present invention. At the same time, the materials used in this article are polyurethane elastic materials and steel elastic-plastic materials, and the scope of elastic materials and elastic-plastic materials is very broad. As long as the materials belong to the category of elastic materials and elastic-plastic materials, they are all included in the scope of applicable materials of this article.

[0055] The above is only an embodiment of the present invention, and the present invention is not limited to this embodiment. Any simple modification or replacement without departing from the principle and basic features of the present invention shall fall within the protection scope of the present invention.

Claims

1. A repeatable energy absorbing structure composed of an elastic material and an elastoplastic material, characterized in that: include: An energy absorbing unit made of elastic-plastic material; A support unit made of elastic material; The support unit is arranged between the energy absorbing units, and is used for providing an anti-deformation force when the energy absorbing unit absorbs energy, and providing a restoring force after the energy absorbing unit absorbs energy.

2. The repeatable energy absorbing structure according to claim 1, characterized in that: The energy absorbing unit is an arc corrugated plate.

3. The repeatable energy absorbing structure according to claim 2, characterized in that: The arc corrugated plate is formed by connecting the arc segments of the upper and lower mirror images one by one through two end points; the curvature φ of the arc segment affects the bending moment M of the unit during the bending process, where M is EIφ, and E is the elastic modulus of the material, and I is the moment of inertia of the material. The moment of inertia I is related to the cube of the thickness t of the cross section. The bending modulus Eb of the corrugated plate is Eb=L 3 / EI, which is related to the length L of the arc segment. The length L of the arc is controlled by the center angle θ of the arc segment and the radius r of the arc segment. The center angle θ is in the range of 60°-120°, and the radius r of the arc segment should be in the range of 3t-6t.

4. The repeatable energy absorbing structure according to claim 2 or 3, characterized in that: The two adjacent arc corrugated plates are topologically formed into an integral structure through upper and lower mirror images.

5. The repeatable energy absorbing structure according to claim 1, characterized in that: The energy absorbing structure is a honeycomb structure obtained by mirroring the corrugated plate, and the overall structure is formed by staggered stacking of the corrugated plate and the elastic material.

6. The repeatable energy absorbing structure according to claim 1, characterized in that: The energy absorbing structure is a structure made of elastic-plastic material pre-made by 3D printing, and the elastic block material is filled in to obtain the overall structure, and the overall structure is obtained by using a corrugated plate structure mixed with elastic material and elastic-plastic material by translating the corrugated plate or mirroring the corrugated plate.

7. The repeatable energy absorbing structure according to claim 1, characterized in that: The elastic material constituting the supporting unit is rubber material, polyurethane, foam or sponge.

8. The repeatable energy absorbing structure according to claim 1, characterized in that: The supporting unit is a spring.

9. The repeatable energy absorbing structure according to claim 1, characterized in that: The elastic material constituting the energy absorbing unit is metal material or plastic.

10. The repeatable energy absorbing structure according to claim 9, characterized in that: The metal material constituting the energy absorbing unit is steel, aluminum or copper.

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