Reinforced sandwich window for manned spacecraft

Abstract

The present application belongs to the field of aerospace vehicle structure design and safety protection technology, and discloses a manned space vehicle reinforced sandwich window, which embeds an integrated reinforcing grid in a transparent sandwich layer, upgrades a homogeneous laminated structure into an anisotropic reinforced structure, and comprises an outer impact-resistant panel, a reinforcing grid sandwich layer and an inner pressure-bearing panel. Under the same surface density, the bending stiffness, perforation resistance and blast resistance are significantly improved, and the weight is reduced. After the outer layer is penetrated, the internal grid effectively blocks debris and maintains air tightness, providing redundant safety. Through precise matching of the refractive index of the material, the light transmittance is ensured to be greater than 90%, and the optical distortion is low. The thermal expansion coefficient is matched to reduce thermal stress and improve thermal reliability. The function of integrated heating and demisting is supported. The present application greatly enhances the safety and functionality under weight control, and provides a breakthrough solution for the design of the manned spacecraft window.

Description

Technical Field

[0001] This invention belongs to the field of aerospace vehicle structural design and safety protection technology, specifically relating to a reinforced sandwich porthole for manned spacecraft. Background Technology

[0002] Portholes are critical components of manned spacecraft, providing occupants with a means of observation. However, their structural integrity directly impacts the airtightness of the entire cabin and occupant safety. Traditional spacecraft portholes typically employ a "sandwich" structure of multiple layers of glass or transparent polymers, bonded together with polymer films (such as PVB). This structure exhibits significant limitations when facing high-speed impacts from micrometeoroids and space debris, the immense pressure differentials during launch / reentry, and intense thermal cycling. Improving resistance to high-speed space debris impacts usually requires increasing glass thickness and the number of layers, making the porthole one of the heaviest non-load-bearing components on the spacecraft, severely limiting payload capacity. The interlayer interfaces of the sandwich structure are mechanically weak points, prone to delamination and debonding under repeated impacts or thermal stress, leading to optical performance degradation and sealing failure. Uniform material distribution, without optimization based on stress distribution, results in low material utilization. The use of small-sized windows for safety limits the occupants' field of vision. Current technologies lack innovative solutions that achieve a breakthrough balance between material thickness (weight) and structural strength / safety. Therefore, there is an urgent need for a new type of porthole that can innovate from the perspective of structural mechanics and provide impact resistance and load-bearing capacity far exceeding that of traditional structures with the same or lighter weight. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a reinforced laminated porthole for manned spacecraft. By embedding an integrated reinforcing mesh in the transparent interlayer, the traditional homogeneous laminated structure is transformed into an anisotropic reinforced structure, thereby greatly improving the bending resistance, impact resistance and explosion resistance of the porthole without significantly increasing the thickness and weight, and effectively inhibiting crack propagation.

[0004] The technical solution adopted in this invention is: a reinforced sandwich window for a manned spacecraft, comprising: an outer impact-resistant panel, a reinforcing mesh interlayer, a frame, and an inner pressure-bearing panel; the outer impact-resistant panel, the reinforcing mesh interlayer, and the inner pressure-bearing panel are disposed within the frame; the outer impact-resistant panel is located on the outside side of the cabin, the inner pressure-bearing panel is located on the inside side of the cabin, and the reinforcing mesh interlayer is located between the outer impact-resistant panel and the inner pressure-bearing panel; the outer impact-resistant panel is made of transparent ceramic or chemically strengthened glass; the reinforcing mesh interlayer includes a fiber braided layer and a transparent resin matrix, the transparent resin matrix being attached to the fiber braided layer; the inner pressure-bearing panel is made of high molecular weight polycarbonate or polyurethane.

[0005] Furthermore, the fiber braided layer is made of a transparent composite material with a strength of 2.5~3GPa through pultrusion and weaving.

[0006] Furthermore, the transparent resin matrix has an elongation greater than 10% when the operating temperature is -60℃ to 150℃, and the material of the transparent resin matrix is ​​PU or TPU.

[0007] Furthermore, the reinforcing mesh interlayer includes one or more fiber braided layers; When the reinforcing mesh interlayer includes a fiber braided layer, the fiber braided layer is a three-dimensional braided layer or a two-dimensional braided layer. When the fiber braided layer is a three-dimensional braided layer, the yarn is 50~100 dtex; when the fiber braided layer is a two-dimensional braided layer, the yarn is 400~500 dtex. When the reinforcing mesh interlayer includes multiple fiber braided layers, the thickness of the fiber braided layers is 0.1mm~0.2mm, and the fiber braided layers are heat-sealed with a resin matrix.

[0008] Furthermore, the reinforcing mesh in the reinforcing mesh interlayer is an orthogonal mesh, a hexagonal honeycomb mesh, or a biomimetic mesh structure.

[0009] Furthermore, the yarns in the fiber braided layer are thicker the closer they are to the edge.

[0010] Furthermore, the surface of the fiber braided layer is treated with a silane coupling agent.

[0011] Furthermore, the aforementioned reinforced sandwich window for a manned spacecraft also includes a light-transmitting panel, which is disposed inside the inner pressure-bearing panel and is made of resin material.

[0012] Furthermore, the outer impact-resistant panel, the reinforcing mesh interlayer, the inner pressure-bearing panel, and the light-transmitting panel are bonded together with optical adhesive to ensure that the light transmittance of the reinforcing mesh porthole is >90%.

[0013] Furthermore, the reinforced laminated porthole is coated with an anti-reflective coating and an anti-static coating on both its inner and outer surfaces.

[0014] The advantages of this invention compared to the prior art are: (1) This invention aims to solve the problems of traditional portholes caused by their multi-layered glass / polymer structure, such as heavy weight (heaviest non-load-bearing component), easy delamination and debonding, insufficient impact resistance, and limited field of vision. This invention uses a reinforced mesh interlayer, which can effectively disperse and absorb impact energy and inhibit crack propagation. Under the same areal density, its bending stiffness, perforation resistance, and explosion resistance far exceed those of traditional homogeneous interlayer structures, achieving significant weight reduction.

[0015] (2) Even if the outer panel is punctured, the internal reinforcing mesh and tough inner layer can effectively prevent fragments from penetrating and maintain the integrity and airtightness of the overall structure, providing redundant safety protection.

[0016] (3) The present invention ensures high light transmittance (>90%) and low optical distortion of the reinforced interlayer by precisely matching the refractive index of the materials (mesh, resin, adhesive), thus meeting the observation requirements.

[0017] (4) The thermal expansion coefficient of the composite material mesh of the present invention can be designed to better match the panel material, thereby reducing the thermal stress of the entire structure and improving the reliability under severe temperature alternation environment.

[0018] (5) The topology, density, and orientation of the reinforcing mesh of the present invention can be customized according to the specific shape and stress conditions of the porthole to achieve optimal material distribution. This structure is easy to integrate with functions such as heating and defogging, and conductive shielding. Attached Figure Description

[0019] Figure 1 This is an exploded view of the structure of the present invention; Figure 2 This is a schematic diagram of the overall structure of the high-strength reinforced sandwich porthole of the present invention; Figure 3 A schematic diagram of the structure for reinforcing the mesh interlayer. Detailed Implementation

[0020] The present invention will be described in conjunction with the accompanying drawings.

[0021] like Figure 1 , Figure 2 As shown, a reinforced laminated porthole for a manned spacecraft comprises, from the outside to the inside of the cabin, the following components: Outer impact-resistant panel 1: Made of transparent ceramic (such as magnesium aluminum spinel MgAl2O4) or chemically strengthened glass, it serves as the first barrier against high-speed impacts from space debris and aerodynamic loads. It can effectively disperse and absorb impact energy, inhibit crack propagation, and improve bending stiffness, perforation resistance, and explosion resistance.

[0022] Reinforced mesh interlayer 2: Located between the outer impact-resistant panel 1 and the inner pressure-bearing panel 4. The reinforced mesh interlayer 2 includes a fiber braided layer and a transparent resin matrix. The fiber braided layer comprises a transparent composite material (preferably Vectran, aramid, polyimide, or glass fiber) with a strength of 2.5~3 GPa, bearing the internal and external pressures of the cabin and external impact loads, improving load-bearing capacity, reducing the thickness of the porthole, achieving lightweight porthole design, reducing overall deformation, and avoiding the impact of deformation on the aerodynamic shape and cabin shape. The transparent resin matrix is ​​attached to the fiber braided layer. The transparent resin matrix has an elongation greater than 10% at an operating temperature range of -60~150℃. Preferably, the transparent resin matrix material is PU or TPU.

[0023] Inner pressure-bearing panel 4: Made of high molecular weight polycarbonate (PC) or polyurethane (PU), it has excellent toughness and serves as the main pressure-bearing structure for airtight sealing, and prevents fragments from flying after impact.

[0024] Furthermore, the reinforcing mesh interlayer 2 includes one or more fiber braided layers. When the reinforcing mesh interlayer 2 includes one fiber braided layer, the fiber braided layer is a three-dimensional or two-dimensional braided layer. When the fiber braided layer is a three-dimensional braided layer, the yarn is 50~100 dtex; when the fiber braided layer is a two-dimensional braided layer, the yarn is 400~500 dtex (dtex refers to the weight in grams of 10000m of yarn at a standard moisture regain; it is a unit of length, and the higher the weight, the thicker the yarn, often used to express the fineness of the yarn; 1 dtex = 1g / 10000m). When the reinforcing mesh interlayer 2 includes multiple fiber braided layers, the thickness of the transparent fiber braided layer is 0.1mm~0.2mm, and the fiber braided layers are heat-sealed together with a resin matrix.

[0025] Furthermore, the shape of the reinforcing mesh can be designed as an orthogonal mesh, a hexagonal honeycomb mesh, or a biomimetic mesh structure.

[0026] Furthermore, the yarn is thicker closer to the edge of the reinforced mezzanine porthole, such as... Figure 3 As shown, the diameter ratio of yarns H1 and H5 to the diameter ratio of yarns H2 and H4 to the diameter ratio of yarn H3 is 1.2:1.1:1, and the diameter ratio of yarns Z1, Z2, Z8, and Z9 to the diameter ratio of yarns Z3, Z4, Z6, and Z7 to the diameter ratio of yarn Z5 is 1.2:1.1:1. This improves material utilization and achieves optimal material distribution and lightweighting.

[0027] Furthermore, the fibers of the fiber braided layer are formed by pultrusion and weaving of transparent composite materials.

[0028] Furthermore, the porthole structure also includes a light-transmitting panel 5: made of a resin material with a refractive index that matches the reinforcing mesh, such as transparent polyurethane (PU) or silicone, to ensure the optical transparency of the entire interlayer.

[0029] Functional interface layer: Optical adhesives are used to bond the surfaces of each layer, with refractive indices matched to adjacent materials to reduce interface reflection. Anti-reflective (AR) and antistatic (AS) coatings can be optionally applied to the inner and outer surfaces. Precise matching of material refractive indices (mesh, resin, adhesive) ensures high light transmittance (>90%) and low optical distortion in the reinforced laminated porthole, meeting observation requirements.

[0030] Furthermore, the surface of the fiber braided layer is treated with a silane coupling agent to enhance its interfacial bonding strength with the transparent resin matrix and prevent debonding.

[0031] Furthermore, the edge of the inner reinforced sandwich window is connected to the aircraft cabin through flexible sealing materials and mechanical clamping, allowing the structure to undergo slight displacement due to thermal expansion and contraction, thus avoiding thermal stress damage.

[0032] The parts of this invention not described in detail are well-known to those skilled in the art.

Claims

1. A reinforced laminated porthole for a manned spacecraft, characterized in that, include: Outer impact-resistant panel (1), reinforced mesh interlayer (2), frame (3) and inner pressure-bearing panel (4); An outer impact-resistant panel (1), a reinforcing mesh interlayer (2), and an inner pressure-bearing panel (4) are arranged inside a frame (3); the outer impact-resistant panel (1) is located on the outside side of the cabin, the inner pressure-bearing panel (4) is located on the inside side of the cabin, and the reinforcing mesh interlayer (2) is located between the outer impact-resistant panel (1) and the inner pressure-bearing panel (4); the outer impact-resistant panel (1) is made of transparent ceramic or chemically strengthened glass; the reinforcing mesh interlayer (2) includes a fiber braided layer and a transparent resin matrix, with the transparent resin matrix attached to the fiber braided layer; the inner pressure-bearing panel (4) is made of high molecular weight polycarbonate or polyurethane.

2. The reinforced laminated porthole for a manned spacecraft according to claim 1, characterized in that, The fiber braided layer is made of a transparent composite material with a strength of 2.5~3GPa through pultrusion and weaving.

3. A reinforced laminated porthole for a manned spacecraft according to claim 2, characterized in that, The transparent resin matrix has an elongation greater than 10% when the operating temperature is -60℃ to 150℃, and the material of the transparent resin matrix is ​​PU or TPU.

4. A reinforced laminated porthole for a manned spacecraft according to claim 3, characterized in that, The reinforced mesh interlayer (2) includes one fiber braided layer or multiple fiber braided layers; When the reinforcing mesh interlayer (2) includes a fiber braided layer, the fiber braided layer is a three-dimensional braided layer or a two-dimensional braided layer. When the fiber braided layer is a three-dimensional braided layer, the yarn is 50~100dtex; when the fiber braided layer is a two-dimensional braided layer, the yarn is 400~500dtex. When the reinforcing mesh interlayer (2) includes multiple fiber braided layers, the thickness of the fiber braided layers is 0.1mm~0.2mm, and the fiber braided layers are heat-sealed with a resin matrix.

5. A reinforced laminated porthole for a manned spacecraft according to claim 4, characterized in that, The reinforcing mesh in the reinforcing mesh interlayer (2) is an orthogonal mesh, a hexagonal honeycomb mesh, or a biomimetic mesh structure.

6. A reinforced laminated porthole for a manned spacecraft according to claim 5, characterized in that, The closer the yarn in the fiber braided layer is to the edge (3), the thicker the yarn is.

7. A reinforced laminated porthole for a manned spacecraft according to claim 6, characterized in that, The surface of the fiber braided layer is treated with a silane coupling agent.

8. A reinforced laminated porthole for a manned spacecraft according to claim 7, characterized in that, It also includes a light-transmitting plate (5), which is set inside the inner pressure-bearing panel (4) and is made of resin material.

9. A reinforced laminated porthole for a manned spacecraft according to claim 8, characterized in that, The outer impact-resistant panel (1), the reinforcing mesh interlayer (2), the inner pressure-bearing panel (4) and the light-transmitting panel (5) are bonded together with optical adhesive to ensure that the light transmittance of the reinforcing mesh porthole is >90%.

10. A reinforced laminated porthole for a manned spacecraft according to claim 9, characterized in that, The reinforced laminated porthole is coated with anti-reflective and anti-static coatings on both its inner and outer surfaces.

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