CN114633941B - A light-weight thermal insulation protection box with anti-drop impact - Google Patents

Abstract

The invention relates to a drop-shock-resistant lightweight heat-preservation protection box, which belongs to the technical field of protection boxes. The protective box includes a buffer heat preservation outer layer, a lightweight box body and a buffer protection inner layer, the buffer heat preservation outer layer is wrapped outside the light weight box body, and the buffer protection inner layer is installed inside the light weight box body; wherein, the buffer heat preservation Both the outer layer and the buffer protection inner layer are made of polyurethane elastomer with a density of 300-400kg/m ³ , a thermal conductivity of 0.03-0.04W/(m·K), and an energy absorption per unit volume of 60-120MJ/m ³ , which is lightweight The box body is made of fiber composite or alloy materials with a density of 1.5-2.7g/cm ³ , a tensile strength of ≥200MPa, and a compressive strength of ≥200MPa. There are limited grooves, and the lightweight box is a closed hollow box formed by the upper box and the lower box through the buckle assembly. The protection box of the present invention is simple in structure, easy to manufacture, convenient to disassemble and assemble, and has the characteristics of light weight, heat preservation and energy absorption, etc., and has strong versatility.

Description

A lightweight thermal insulation protective box that resists drop impact

Technical Field

The invention relates to a drop-impact resistant lightweight heat-insulating protective box, belonging to the technical field of protective boxes.

Background Art

Soldiers and doctors need to airdrop supplies to specific locations when they are on duty in harsh environments and rescuing in earthquake relief areas. For example, when transporting emergency medical equipment, medicines, food, ammunition and other supplies to harsh environments and disaster areas, if roads and railways cannot reach the area, drones need to be used for airdrop. In order to ensure that equipment, medicines, food, ammunition and other supplies arrive at the designated location safely and intact, the packaging box is equipped with a buffer device to reduce the impact on the contents at the moment of landing. As the requirements for packaging boxes for military materials become higher and higher during transportation and storage, traditional wooden boxes, iron boxes, roto-molded boxes, PP thermoplastic materials, etc. have the characteristics of heavy weight, poor maneuverability, inconvenient loading and unloading, poor weather resistance, lack of insulation, and the box body does not have a buffer function at the moment of landing, which cannot meet the requirements of existing military materials for packaging carriers. At present, aluminum honeycomb paperboard and foam aluminum buffer materials are used to prepare protective boxes to overcome the shortcomings of traditional material protective boxes, but their production costs are high and cannot be put into mass service.

Summary of the invention

In view of the shortcomings of the prior art, the present invention provides a lightweight thermal insulation protective box that is resistant to drop impacts. It adopts a composite structure design of an outer buffering and thermal insulation structure, a lightweight skeleton structure and an inner buffering and protective structure. It can not only play a landing buffer role but also provide an effective thermal insulation function for the protective box. Moreover, each part of the structure is easy to mass produce and is convenient to assemble and disassemble, and has a good application prospect.

The objectives of the present invention are achieved through the following technical solutions.

A drop-impact resistant lightweight thermal insulation protection box, the protection box comprising a buffer thermal insulation outer layer, a lightweight box body and a buffer protection inner layer, the buffer thermal insulation outer layer is wrapped on the outside of the lightweight box body, and the buffer protection inner layer is installed inside the lightweight box body;

The buffer and thermal insulation outer layer is made of polyurethane elastomer with a density of 300-400 kg/m ³ , a thermal conductivity of 0.03-0.04 W/(m·K) and an energy absorption per unit volume of 60-120 MJ/m ³ ; the buffer and thermal insulation outer layer is processed with a hemispherical convex structure;

The lightweight box body is made of fiber composite material or alloy material with a density of 1.5-2.7 g/cm ³ , a tensile strength of ≥200 MPa and a compressive strength of ≥200 MPa; the lightweight box body is a closed hollow box body formed by an upper box body and a lower box body through a buckle assembly;

The buffer protection inner layer is made of polyurethane elastomer with a density of 300-400 kg/m ³ , a thermal conductivity of 0.03-0.04 W/(m·K) and an energy absorption per unit volume of 60-120 MJ/m ³ ; and a limiting groove is provided on the buffer protection inner layer.

Furthermore, the thickness of the buffer and thermal insulation outer layer is σ, the radius of the hemispherical convex structure on the buffer and thermal insulation outer layer is r, and the number of hemispherical convex structures evenly distributed on the buffer and thermal insulation outer layer is n, then

6h ₁ ≤r ≤8h ₁

Among them, _c1 represents the specific heat capacity of the contents, _m1 represents the mass of the contents, _c2 represents the specific heat capacity of the polyurethane elastomer, _T2 represents the initial ambient temperature in the protective box, _T'1 represents the initial temperature of the contents, _T'2 represents the final temperature in the protective box (or the contents), the negative sign represents that the heat transfer direction is opposite to the direction of the temperature gradient, λ represents the thermal conductivity, t represents the insulation time, g represents the acceleration of gravity, W represents the width of the protective box, H represents the falling height of the protective box, A represents the surface area of the protective box, M represents the total mass of the contents in the protective box, V represents the volume of the protective box, ρ represents the density of the polyurethane elastomer, V_台is the total volume of all hemispherical convex structures on the buffer and thermal insulation outer layer, and _h1 is the stacking height of all hemispherical convex structures evenly distributed to the outer surface of the buffer and thermal insulation outer layer.

Furthermore, the polyurethane elastomer material selected for the buffering and heat-insulating outer layer and the buffering and protective inner layer is obtained by curing and molding component A and component B;

The component A is prepared by uniformly mixing polyether polyol, chain extender, foaming agent, catalyst, pore opening agent and filler; the polyether polyol is polyoxypropylene triol (EP-330N) with a functionality of 3 and a molecular weight of 5000 and polyoxypropylene diol (ED-14) with a functionality of 2 and a molecular weight of 8000, the chain extender is 1,4-butanediol (BDO), the foaming agent is H ₂ O, the catalyst is bis(dimethylaminoethyl) ether (BDMAEE) and dibutyltin dilaurate (T12), the pore opening agent is pore opening silicone oil (preferably the pore opening silicone oil with the brand name ECOADD-019C produced by Shanghai Yexing Industrial Co., Ltd.), and the filler is activated carbon fiber; the mass fractions of each component in the raw materials of component A are as follows: EP-330N 15-25 parts, ED-14 65-75 parts, BDO 3-10 parts, H ₂ O 0.40-0.48 parts, BDMAEE 0.10-0.15 parts, T12 0.01-0.02 parts, open-pore silicone oil 0.85-0.95 parts, activated carbon fiber 2-6 parts;

The B component is polymethylene polyphenyl isocyanate (PM-200); the molar ratio of -NCO groups contained in the B component to active -H contained in the A component is (0.98-1.03):1.00, wherein the active -H in the A component is the sum of the active -H in the polyol -OH and the active -H in _H2O .

Furthermore, the specific operation of the reaction of component A and component B is as follows: first preheat component A to 35±2°C and component B to 45±2°C, then pour the preheated component A and the preheated component B into a mold preheated to 65±5°C, and cure at 60-70°C to obtain a polyurethane elastomer.

Furthermore, the lightweight box body is made of glass fiber composite material, carbon fiber composite material, basalt fiber composite material, aluminum alloy material or titanium alloy material.

Beneficial effects:

(1) The present invention adopts a composite structure design of an outer buffer insulation structure, a lightweight skeleton structure and an inner buffer protection structure, which can not only play a role in cushioning the impact of falling but also provide an effective thermal insulation function for the protective box. It can also resist attacks from wind and sand, extreme heat, severe cold, and falling from a high altitude. It has the functions of strong impact resistance, high and low temperature resistance, buffering and shock absorption, waterproof and moisture-proof, UV protection, dustproof and corrosion resistance. It can ensure the integrity, usability and reliability of the internally loaded materials in various harsh environments such as jungles, deserts, aviation, navigation, and plateaus.

(2) The buffering and heat-insulating outer layer of the present invention is arranged outside the lightweight box. The hemispherical convex structure on its surface will first contact the ground, and absorb a large amount of impact energy through the collapse of the bubbles in the polyurethane elastomer, thereby reducing the damage of the impact energy to the contents of the protective box. At the same time, the thermal conductivity of the buffering and heat-insulating outer layer is extremely low, and has a good thermal insulation effect.

(3) The present invention provides a buffering protective inner layer in the lightweight box. The inner protective layer can ensure that the contents do not come into contact with each other and can also provide a certain buffering and heat preservation effect.

(4) All structural parts of the protective box described in the present invention can be produced in a modular manner, and the parts can be easily assembled and disassembled. At the same time, each part can be individually designed according to the actual working conditions of the protective box, thereby enabling the protective box to adapt to various external working conditions and different internal structures to match the corresponding internal materials. It has strong versatility and good application prospects.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a front view of the drop-impact-resistant lightweight thermal insulation protective box described in Example 1; in the figure, 1 is a hemispherical protrusion structure, and 2 is a buckle assembly.

DETAILED DESCRIPTION

The present invention is further described below in conjunction with specific embodiments, wherein the methods are conventional methods unless otherwise specified, and the raw materials can be obtained from public commercial channels unless otherwise specified.

Example 1

A drop-impact resistant lightweight thermal insulation protection box, the protection box comprising a buffer thermal insulation outer layer, a lightweight box body and a buffer protection inner layer, the buffer thermal insulation outer layer is wrapped on the outside of the lightweight box body, and the buffer protection inner layer is installed inside the lightweight box body;

The buffer thermal insulation outer layer and the buffer protection inner layer are both made of polyurethane elastomer with a density of 300-400 kg/m ³ , a thermal conductivity of 0.03-0.04 W/(m·K) and an energy absorption per unit volume of 60-120 MJ/m ³ . The specific preparation steps of the polyurethane elastomer are as follows: firstly preheating component A to 35±2°C and component B to 45±2°C, then pouring the preheated component A and component B into a mold preheated to 65±5°C, and curing and molding at 60-70°C to obtain a polyurethane elastomer; wherein component A is composed of 15-25 parts of EP-330N, 65-75 parts of ED-14, 3-10 parts of BDO, 0.40-0.48 parts of H ₂ O, 0.10-0.15 parts of BDMAEE, and T12 0.01-0.02 parts, 0.85-0.95 parts of open-pore silicone oil ECOADD-019C produced by Shanghai Yexing Industrial Co., Ltd. and 2-6 parts of activated carbon fiber are uniformly mixed and prepared, component B is PM-200, and the molar ratio of -NCO group contained in component B to active -H contained in component A is (0.98-1.03):1.00;

The buffer thermal insulation outer layer is processed with uniformly distributed hemispherical convex structures 1, as shown in FIG1 ; the thickness of the buffer thermal insulation outer layer is σ, the radius of the hemispherical convex structure 1 on the buffer thermal insulation outer layer is r, and the number of uniformly distributed hemispherical convex structures 1 on the buffer thermal insulation outer layer is n, then:

6h ₁ ≤r ≤8h ₁

Wherein, _c1 represents the specific heat capacity of the contents, _m1 represents the mass of the contents, _c2 represents the specific heat capacity of the polyurethane elastomer, _T2 represents the initial ambient temperature in the protection box, _T'1 represents the initial temperature of the contents, _T'2 represents the final temperature in the protection box (or the contents), the negative sign represents that the heat transfer direction is opposite to the temperature gradient direction, λ represents the thermal conductivity, t represents the insulation time, g represents the acceleration of gravity, W represents the width of the protection box, H represents the falling height of the protection box, A represents the surface area of the protection box, M represents the total mass of the contents in the protection box, V represents the volume of the protection box, ρ represents the density of the polyurethane elastomer, V_台is the total volume of all hemispherical convex structures 1 on the buffer insulation outer layer, and _h1 is the stacking height of all hemispherical convex structures 1 evenly distributed to the outer surface of the buffer insulation outer layer;

The lightweight box is made of a fiber composite material or alloy material (such as glass fiber composite material, carbon fiber composite material, basalt fiber composite material, aluminum alloy material or titanium alloy material) with a density of 1.5-2.7 g/cm ³ , a tensile strength of ≥200 MPa and a compressive strength of ≥200 MPa; the lightweight box is a closed hollow box formed by an upper box and a lower box through a buckle assembly 2, as shown in FIG1 ;

The buffer protection inner layer is provided with a limiting groove, the specific structure of which is designed according to the specific contents to be loaded, and is used to fix the contents and prevent the contents from contacting each other and causing damage to the contents;

The buffering and heat-insulating outer layer and the buffering and protective inner layer of the protection box described in this embodiment are both made of polyurethane elastomer with low density, low thermal conductivity, excellent buffering and energy absorption performance and excellent mechanical properties. The lightweight box body is made of lightweight materials with excellent mechanical properties, and a hemispherical protrusion structure is processed on the surface of the buffering and heat-insulating outer layer to ensure that the protection box has good anti-buffering and thermal insulation properties on the basis of light weight. In addition, the various structural parts of the protection box are easy to mass produce and easy to assemble and disassemble, and each part can be individually designed according to the actual operating conditions of the protection box, so that the protection box can meet the application requirements of various external working conditions and different internal materials.

In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims (4)

1. A drop-resistant lightweight thermal insulation protection box, characterized in that: the protection box comprises a buffer thermal insulation outer layer, a lightweight box body and a buffer protection inner layer, the buffer thermal insulation outer layer is wrapped on the outside of the lightweight box body, and the buffer protection inner layer is installed inside the lightweight box body; The buffer insulation outer layer and the buffer protection inner layer are both made of polyurethane elastomer with a density of 300-400 kg/m ³ , a thermal conductivity of 0.03-0.04 W/(m·K) and an energy absorption per unit volume of 60-120 MJ/m ³ ; the buffer insulation outer layer is processed with a hemispherical convex structure, and the buffer protection inner layer is provided with a limiting groove; The lightweight box body is made of fiber composite material or alloy material with a density of 1.5-2.7 g/cm ³ , a tensile strength of ≥200 MPa and a compressive strength of ≥200 MPa; the lightweight box body is a closed hollow box body formed by an upper box body and a lower box body through a buckle assembly; The thickness of the buffer and thermal insulation outer layer is σ, the radius of the hemispherical convex structure on the buffer and thermal insulation outer layer is r, and the number of hemispherical convex structures evenly distributed on the buffer and thermal insulation outer layer is n, then

6h ₁ ≤r ≤8h ₁

Among them, _c1 represents the specific heat capacity of the contents, _m1 represents the mass of the contents, _c2 represents the specific heat capacity of the polyurethane elastomer, _T2 represents the initial ambient temperature in the protection box, _T'1 represents the initial temperature of the contents, _T'2 represents the final temperature in the protection box, the negative sign represents that the heat transfer direction is opposite to the temperature gradient direction, λ represents the thermal conductivity, t represents the insulation time, g represents the acceleration of gravity, W represents the width of the protection box, H represents the falling height of the protection box, A represents the surface area of the protection box, M represents the total mass of the contents in the protection box, V represents the volume of the protection box, ρ represents the density of the polyurethane elastomer, V_台is the total volume of all hemispherical convex structures on the buffer insulation outer layer, and _h1 is the stacking height of all hemispherical convex structures evenly distributed to the outer surface of the buffer insulation outer layer. 2. A drop-impact-resistant lightweight thermal insulation protection box according to claim 1, characterized in that: the polyurethane elastomer material selected for the buffer thermal insulation outer layer and the buffer protection inner layer is obtained by reaction curing and molding of component A and component B; Calculated by the mass fraction of each component in the raw material of component A, component A is uniformly prepared by mixing 15-25 parts of EP-330N, 5-75 parts of ED-146, 3-10 parts of BDO, 0.40-0.48 parts of _H2O , 0.10-0.15 parts of BDMAEE, 0.01-0.02 parts of T12, 0.85-0.95 parts of open-pore silicone oil and 2-6 parts of activated carbon fiber; Component B is PM-200, and the molar ratio of -NCO groups contained in component B to active -H contained in component A is (0.98-1.03):1.00. 3. A drop-impact-resistant lightweight thermal insulation protective box according to claim 2, characterized in that the specific operation of the reaction of component A and component B is as follows: first preheat component A to 35±2°C and component B to 45±2°C, then pour the preheated component A and the preheated component B into a mold preheated to 65±5°C, and cure them at 60-70°C to obtain a polyurethane elastomer. 4. A drop-impact-resistant lightweight thermal insulation protective box according to claim 1, characterized in that the material of the lightweight box body is selected from glass fiber composite materials, carbon fiber composite materials, basalt fiber composite materials, aluminum alloy materials or titanium alloy materials.

Images