An impact-resistant covering structure

Abstract

This invention provides an impact-resistant covering structure, relating to the field of vibration reduction technology. The impact-resistant covering structure includes alternating first and second energy-absorbing layers. The first energy-absorbing layer comprises a first elastic substrate and a plurality of first energy-absorbing elements regularly distributed within the first elastic substrate. The second energy-absorbing layer comprises a second elastic substrate and a plurality of second energy-absorbing elements regularly distributed within the second elastic substrate. The density of the first energy-absorbing elements is greater than the density of the first elastic substrate. The amount of first energy-absorbing elements in the first energy-absorbing layer varies gradient along the thickness direction of the impact-resistant covering structure, and the arrangement angle of the second energy-absorbing elements in the second energy-absorbing layer also varies gradient along the thickness direction of the impact-resistant covering structure. This invention can effectively improve the impact resistance of the impact-resistant covering structure.

Description

Technical Field

[0001] This invention relates to the field of vibration reduction technology, and more specifically, to an impact-resistant covering structure. Background Technology

[0002] Underwater vehicles typically employ shock-resistant covering structures for blast protection. For example, to reduce the damage from shock waves generated by underwater non-contact explosions, underwater vehicles are usually covered with a shock-resistant covering structure on their outer surface to weaken the shock waves generated by non-contact explosions and improve the underwater vehicle's shock resistance.

[0003] Traditional impact-resistant covering structures are generally made of rubber with good wear resistance. However, when subjected to external shock waves, they are prone to large deformation, resulting in weak impact resistance and making it impossible to guarantee the impact resistance effect. Summary of the Invention

[0004] The problem addressed by this invention is how to improve the impact resistance of impact-resistant covering structures under impact pressure.

[0005] To address the aforementioned problems, the present invention provides an impact-resistant covering structure, comprising an alternately laid first energy-absorbing layer and a second energy-absorbing layer, wherein the first energy-absorbing layer comprises a first elastic substrate and a plurality of first energy absorbers regularly distributed within the first elastic substrate; and the second energy-absorbing layer comprises a second elastic substrate and a plurality of second energy absorbers regularly distributed within the second elastic substrate.

[0006] Wherein, the density of the first energy absorber is greater than the density of the first elastic substrate, the amount of the first energy absorber in the first energy-absorbing layer varies gradient along the thickness direction of the impact-resistant covering structure, and the arrangement angle of the second energy absorber in the second energy-absorbing layer varies gradient along the thickness direction of the impact-resistant covering structure.

[0007] Preferably, both the first elastic substrate and the second elastic substrate comprise polyurea elastomer.

[0008] Preferably, the first energy absorber includes metal particles for enhancing impact toughness, and the second energy absorber includes short fibers for enhancing yield strength.

[0009] Preferably, the metal particles are periodically distributed in the first energy-absorbing layer, and the density of the first energy-absorbing layer decreases gradually along the direction close to the covered target.

[0010] Preferably, the second energy-absorbing layer includes an outer second energy-absorbing sublayer disposed on the surface of the impact-resistant covering structure and an inner second energy-absorbing sublayer disposed between the outer second energy-absorbing sublayers;

[0011] The short fibers in the outer energy-absorbing sublayer are arranged in a direction parallel to the surface of the impact-resistant covering structure.

[0012] Preferably, the short fibers in each of the second energy-absorbing layers are arranged in the same direction.

[0013] Preferably, the angular gradient increment of the arrangement angle of the short fibers is 25° to 35°.

[0014] Preferably, the second energy absorber is periodically distributed in the second energy-absorbing layer, and the first energy absorber and the second energy absorber are correspondingly arranged in the thickness direction of the impact-resistant covering structure.

[0015] Preferably, the surface of the metal particles is provided with a rubber encapsulation.

[0016] Preferably, the impact-resistant covering structure further includes an elastic layer laid between the first energy-absorbing layer and the second energy-absorbing layer, the material of which includes a polyurea elastomer.

[0017] Compared to existing technologies, the beneficial effects of the impact-resistant covering structure of the present invention are as follows: The impact-resistant covering structure includes an alternately laid first energy-absorbing layer and a second energy-absorbing layer. When subjected to external impact pressure, since the density of the first energy absorber is greater than the density of the first elastic substrate, the first energy absorber, whose filling amount is gradient distributed within the first elastic substrate, causes a gradient change in the impedance of the first energy-absorbing layer. This results in the external shock wave continuously being transmitted and reflected when passing through the first energy-absorbing layer, thereby reducing the impact pressure. Furthermore, when the shock wave passes through the second energy-absorbing layer, since the arrangement angle of the second energy absorber in the second energy-absorbing layer is gradient-variable, the shock wave is continuously reflected on the surface of the second energy absorber. The gradient-variable angle of the reflected wave causes collisions between the reflected waves, thereby reducing the impact pressure. Moreover, the alternating distribution of the first and second energy-absorbing layers causes the shock wave to continuously be reflected and transmitted between the first and second energy-absorbing layers, resulting in collisions between the shock waves and weakening them, thereby improving the impact resistance performance of the impact-resistant covering structure. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of an impact-resistant covering structure according to an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of an impact-resistant covering structure according to another embodiment of the present invention.

[0020] Explanation of reference numerals in the attached figures:

[0021] 11-First energy-absorbing layer; 111-First elastic substrate; 112-First energy absorber; 12-Second energy-absorbing layer; 121-Second elastic substrate; 122-Second energy absorber; 13-Elastic layer; 2-Target coverage. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0023] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0024] The following describes an impact-resistant covering structure provided by an embodiment of the present invention.

[0025] Reference Figure 1 The present invention provides an impact-resistant covering structure, including an alternately laid first energy-absorbing layer 11 and a second energy-absorbing layer 12. The first energy-absorbing layer 11 includes a first elastic substrate 111 and a plurality of first energy absorbers 112 regularly distributed within the first elastic substrate 111; the second energy-absorbing layer 12 includes a second elastic substrate 121 and a plurality of second energy absorbers 122 regularly distributed within the second elastic substrate 121.

[0026] Wherein, the density of the first energy absorber 112 is greater than the density of the first elastic substrate 111, the amount of the first energy absorber 112 in the first energy absorbing layer 11 varies with gradient along the thickness direction of the impact-resistant covering structure, and the arrangement angle of the second energy absorber 122 in the second energy absorbing layer 12 varies with gradient along the thickness direction of the impact-resistant covering structure.

[0027] It should be explained that in the actual application of impact-resistant covering structures, the structure is laid on the surface of the target to reduce external impact pressure. The first energy-absorbing layer 11 and the second energy-absorbing layer 12 are laid alternately in the impact-resistant covering structure, thereby achieving complementary advantages in energy absorption and enhancing the impact resistance of the structure. The first energy-absorbing layer 11 includes a first elastic substrate 111 and a plurality of first energy absorbers 112 regularly distributed within the first elastic substrate 111. The second energy-absorbing layer 12 includes a second elastic substrate 121 and a plurality of second energy absorbers 122 regularly distributed within the second elastic substrate 121. The different energy absorption methods of the first energy-absorbing layer 11 and the second energy-absorbing layer 12 are mainly based on the types of the first energy absorber 112 and the second energy absorber 122, thereby achieving complementary energy absorption effects between the first energy-absorbing layer 11 and the second energy-absorbing layer 12. By adjusting the distribution parameters (e.g., arrangement space, distribution density) of the first energy absorber 112 in the first energy-absorbing layer 11, the first energy-absorbing layers 11 at different positions can cooperate to improve energy absorption performance. For example, the density of the first energy absorber 112 is greater than the density of the first elastic substrate, that is, the greater the filling amount of the first energy absorber 112, the greater the density of the first energy-absorbing layer 11. By setting the filling amount of the first energy absorber 112 in the first energy-absorbing layer 11 to vary gradually along the direction closer to the coverage target, that is, along the direction closer to the impact-resistant covering... The density gradient of the first energy-absorbing layer 11 in the thickness direction of the cover structure increases or decreases, thereby causing the impedance of the first energy-absorbing layer 11 to change gradient. When the shock wave passes through the first energy-absorbing layer 11, as the impedance of the first energy-absorbing layer 11 changes continuously, the shock wave is continuously transmitted and reflected. As the first energy-absorbing layer 11 advances, the impact pressure is continuously reduced, thereby achieving the effect of impact resistance. The second energy-absorbing layer 12 is set to have a gradient change in the arrangement angle of the second energy-absorbing body 122, so that the impact is continuously reflected when it passes through the second energy-absorbing layer 12. As the second energy-absorbing layer 12 advances, the reflection angle of the shock wave changes continuously, thereby causing the reflected wave to be reflected in multiple directions, resulting in the reflected wave being continuously weakened by collision, thereby achieving the effect of impact resistance.

[0028] The beneficial effects of the impact-resistant covering structure of the present invention are as follows: The impact-resistant covering structure includes an alternately laid first energy-absorbing layer 11 and a second energy-absorbing layer 12. When subjected to external impact pressure, since the density of the first energy-absorbing body 112 is greater than the density of the first elastic substrate 111, the first energy-absorbing body 112, which is filled in the first elastic substrate 111 in a gradient distribution, causes the impedance of the first energy-absorbing layer 11 to change gradient. This causes the external shock wave to be continuously transmitted and reflected when passing through the first energy-absorbing layer 11, thereby reducing the impact pressure. Furthermore, when the shock wave passes through the second energy-absorbing layer 12, since the arrangement angle of the second energy-absorbing body 122 in the second energy-absorbing layer changes gradient, the shock wave is continuously reflected on the surface of the second energy-absorbing body 122. The gradient change in the angle of the reflected wave causes the reflected waves to collide, thereby reducing the impact pressure. Moreover, the alternating distribution of the first energy-absorbing layer 11 and the second energy-absorbing layer 12 causes the shock wave to be continuously reflected and transmitted between the first energy-absorbing layer 11 and the second energy-absorbing layer 12, resulting in collisions between the shock waves and weakening them, thereby improving the impact resistance of the impact-resistant covering structure.

[0029] Furthermore, the first energy absorbers 112 in each first energy-absorbing layer 11 are uniformly arranged, thereby generating multi-directional reflection and transmission of the shock wave, avoiding leakage of the shock wave and the weakening of material durability caused by uneven density; similarly, the second energy absorbers 122 in each second energy-absorbing layer 12 are uniformly arranged, thereby generating multi-directional reflection of the shock wave, also avoiding leakage of the shock wave and the weakening of material durability caused by uneven density. That is, "the amount of the first energy absorber 112 filling in the first energy absorber layer 11 varies gradient along the thickness direction of the impact-resistant covering structure" means that the amount of the first energy absorber 112 filling in different first energy absorber layers 11 varies gradient along the thickness direction of the impact-resistant covering structure, while the first energy absorber 112 in each first energy absorber layer 11 is uniformly distributed. Similarly, "the arrangement angle of the second energy absorber 122 in the second energy absorber layer 12 varies gradient along the thickness direction of the impact-resistant covering structure" means that the arrangement angle of the second energy absorber 122 in different second energy absorber layers 12 varies gradient along the thickness direction of the impact-resistant covering structure, while the arrangement angle of the second energy absorber 122 in each second energy absorber layer 12 is the same.

[0030] In one embodiment, both the first elastic substrate 111 and the second elastic substrate 121 comprise polyurea elastomer. That is, the substrate portions of the first energy-absorbing layer 11 and the second energy-absorbing layer 12 use the same substrate, resulting in good adhesion between the first energy-absorbing layer 11 and the second energy-absorbing layer 12. It is understood that the first energy-absorbing layer 11 and the second energy-absorbing layer 12 can be integrally molded. Polyurea elastomer not only has high elastic modulus and tensile strength, but also high fracture length and short curing time, exhibiting high impact resistance. Therefore, using polyurea elastomer as the substrate of the first energy-absorbing layer 11 and the second energy-absorbing layer 12 can effectively improve the impact resistance of the impact-resistant covering structure.

[0031] In one embodiment, the first energy absorber 112 includes metal particles for enhancing impact toughness, and the second energy absorber 122 includes short fibers for enhancing yield strength. The metal particles possess high hardness and good plasticity, enabling them to effectively absorb and disperse impact energy upon impact. By incorporating metal particles into the first energy-absorbing layer 11, the strength and toughness of the material are increased, effectively preventing material breakage and fragmentation upon impact. The short fibers possess high strength and stiffness, enhancing the material's strength (including but not limited to tensile strength, yield strength, compressive strength, shear strength, and flexural strength). This effectively prevents plastic deformation of the material under external loads, thereby improving the yield strength and stability of the impact-resistant covering structure. Furthermore, the short fibers also increase the toughness and tensile properties of the second energy-absorbing layer 12, further enhancing the impact resistance of the impact-resistant covering structure.

[0032] In one embodiment, the metal particles are periodically distributed in the first energy-absorbing layer 11, and the density of the first energy-absorbing layer 11 decreases gradually along the direction close to the covered target.

[0033] Specifically, the metal particles are periodically distributed within the first energy-absorbing layer 11, meaning they are uniformly distributed within each layer and arranged according to a specific pattern. This ensures that the first energy-absorbing layer 11 can fully utilize its energy-absorbing function when subjected to impact. Simultaneously, the density of adjacent first energy-absorbing layers 11 gradually decreases towards the target being covered. This creates an impedance gradient within the first energy-absorbing layers 11 when the impact-resistant covering structure receives impact pressure, effectively absorbing and dispersing impact energy and improving the impact resistance of the covering structure to achieve optimal performance in practical applications.

[0034] In one embodiment, the second energy-absorbing layer 12 includes an outer second energy-absorbing sublayer disposed on the surface of the impact-resistant covering structure and an inner second energy-absorbing sublayer disposed between the outer second energy-absorbing sublayer;

[0035] The short fibers in the outer energy-absorbing sublayer are arranged in a direction parallel to the surface of the impact-resistant covering structure.

[0036] It is understood that the second energy-absorbing layer 12 includes an outer second energy-absorbing sublayer located on the surface of the impact-resistant covering structure and an inner second energy-absorbing sublayer disposed between the outer second energy-absorbing sublayers. That is, the surfaces of the impact-resistant covering structure and the outside world can both be understood as the outer second energy-absorbing sublayers. The short fiber arrangement direction in the outer second energy-absorbing sublayer is parallel to the surface of the impact-resistant covering structure. When entering or leaving the impact-resistant covering structure, most of the shock wave direction is perpendicular to the surface of the impact-resistant covering structure. Since the short fiber arrangement direction is parallel to the surface of the impact-resistant covering structure, most of the shock wave direction is perpendicular to the surface direction of the short fibers. This allows the shock wave to have the greatest possible reflection effect when leaving or entering the impact-resistant covering structure, thereby improving the impact resistance performance of the impact-resistant covering structure.

[0037] In one embodiment, the short fibers in each of the second energy-absorbing layers 12 are arranged in the same direction.

[0038] It should be explained that "each" here refers to the different arrangement directions of the short fibers in a single second energy-absorbing layer 12, while the arrangement directions of the short fibers in adjacent second energy-absorbing layers 12 show a gradient change. When the arrangement directions of the short fibers in each second energy-absorbing layer 12 are the same, the consistency of the impact resistance of the second energy-absorbing layer 12 is improved, and the arrangement of short fibers in the same direction can increase the strength and stiffness of the second energy-absorbing layer 12, thereby improving the stability of the second energy-absorbing layer 12.

[0039] In one embodiment, the angular gradient increment of the arrangement angle of the short fibers is 25° to 35°.

[0040] Specifically, the arrangement angle of the short fibers in the adjacent second energy-absorbing layer 12 varies from 25° to 35°, which can effectively enhance the energy absorption capacity and impact resistance of the second energy-absorbing layer 12. When an impact occurs, the change in the arrangement angle of the short fibers can effectively change the transmission path and distribution of the shock wave, so that the shock wave can be absorbed more effectively, thereby improving the impact resistance of the impact-resistant covering structure.

[0041] In one embodiment, the surface of the metal particles is provided with a rubber encapsulation.

[0042] Specifically, although metal particles possess high hardness and good plasticity, they are susceptible to adverse reactions from the external environment, such as oxidation or corrosion. Encapsulating the metal particles with a rubber encapsulation provides a protective layer, which helps improve the stability and durability of the metal particles in the first energy-absorbing layer 11. Furthermore, the rubber encapsulation increases the adhesion between the metal particles and the polyurea elastomer, which helps improve the impact resistance and energy absorption capacity of the first energy-absorbing layer 11.

[0043] In one embodiment, the second energy absorber 122 is periodically distributed in the second energy-absorbing layer 12, and the first energy absorber 112 and the second energy absorber 122 are correspondingly arranged in the thickness direction of the impact-resistant covering structure.

[0044] In this embodiment, "corresponding setting" refers to relative or aligned positions. For example, one or more first energy absorbers 112 correspond to one second energy absorber 122, and each second energy absorber 122 is aligned with the corresponding one or more first energy absorbers 112 in the thickness direction of the impact-resistant covering structure.

[0045] Since the first energy absorber 112 and the second energy absorber 122 are respectively arranged in the thickness direction of the impact-resistant covering structure, a relatively stable interlocking structure can be formed between the first energy absorber 112 and the second energy absorber 122, thereby improving the stability and durability of the impact-resistant covering structure.

[0046] Reference Figure 2 The impact-resistant covering structure also includes an elastic layer 13 laid between the first energy-absorbing layer 11 and the second energy-absorbing layer 12, and the material of the elastic layer 13 includes polyurea elastomer.

[0047] Specifically, since the density of the elastic layer 13, which only contains polyurea elastomer, is lower than that of the first energy-absorbing layer 11 containing metal particles, and also lower than that of the second energy-absorbing layer 12 containing short fibers, the elastic layer 13 can be regarded as a soft structure, while the first energy-absorbing layer 11 and the second energy-absorbing layer can be regarded as hard structures. The impact-resistant covering structure, which alternately lays soft and hard structures, can form an impedance mismatch at the intersection of soft and hard structures. When the shock wave passes through the intersection of soft and hard structures, it will be transmitted and scattered, thereby reducing the impact of the shock wave on the covered target 2. At the same time, it gradually reduces the transmission speed of the shock wave, thereby improving the impact resistance of the impact-resistant covering structure.

[0048] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. An impact-resistant covering structure, characterized in that, It includes an alternately laid first energy-absorbing layer (11) and a second energy-absorbing layer (12). The first energy-absorbing layer (11) includes a first elastic substrate (111) and a plurality of first energy absorbers (112) regularly distributed in the first elastic substrate (111). The second energy-absorbing layer (12) includes a second elastic substrate (121) and a plurality of second energy absorbers (122) regularly distributed in the second elastic substrate (121). Wherein, the density of the first energy absorber (112) is greater than the density of the first elastic substrate (111), the filling amount of the first energy absorber (112) in the first energy absorbing layer (11) varies with gradient along the thickness direction of the impact-resistant covering structure, and the arrangement angle of the second energy absorber (122) in the second energy absorbing layer (12) varies with gradient along the thickness direction of the impact-resistant covering structure, the first energy absorber (112) includes metal particles for enhancing impact toughness, and the second energy absorber (122) includes short fibers for enhancing yield strength; The second energy-absorbing layer (12) includes an outer second energy-absorbing sublayer disposed on the surface of the impact-resistant covering structure and an inner second energy-absorbing sublayer disposed between the outer second energy-absorbing sublayers. The short fibers in the outer second energy-absorbing sublayers are arranged in a direction parallel to the surface of the impact-resistant covering structure, and the short fibers in each second energy-absorbing layer (12) are arranged in the same direction.

2. The impact-resistant covering structure according to claim 1, characterized in that, Both the first elastic substrate (111) and the second elastic substrate (121) include polyurea elastomer.

3. The impact-resistant covering structure according to claim 1, characterized in that, The metal particles are periodically distributed in the first energy-absorbing layer (11), and the density of the first energy-absorbing layer (11) decreases gradually along the direction close to the covered target (2).

4. The impact-resistant covering structure according to claim 1, characterized in that, The angular gradient increment of the arrangement angle of the short fibers is 25° to 35°.

5. The impact-resistant covering structure according to claim 1, characterized in that, The surface of the metal particles is coated with a rubber encapsulation.

6. The impact-resistant covering structure according to claim 1, characterized in that, The second energy absorber (122) is periodically distributed in the second energy-absorbing layer (12), and the first energy absorber (112) and the second energy absorber (122) are respectively arranged in the thickness direction of the impact-resistant covering structure.

7. The impact-resistant covering structure according to claim 1, characterized in that, It also includes an elastic layer laid between the first energy-absorbing layer (11) and the second energy-absorbing layer (12), the material of which includes polyurea elastomer.

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