RU205733U1 - ANTI-SHIELDING SHIELDING FABRIC - Google Patents

Abstract

The utility model relates to the field of laminated bullet-resistant materials from ballistic fabric with shielding properties, and can be used in the manufacture of mass protection. The technical result consists in increasing the level of safety of those around (since, for example, even when the VU is triggered under the anti-fragmentation shielding fabric, due to the impossibility of "shielding" the signal with a probability of 100%, the anti-fragmentation layers will significantly reduce the damage caused). An anti-fragmentation shielding fabric comprising a structure containing an interconnected layer of anti-fragmentation ballistic fabric and a layer in the form of a material with shielding properties, while the layer of material with shielding properties contains a mesh with a cell size less than a quarter of the wavelength in the radio range, where the control of the VU is most likely.

Description

The utility model relates to the field of bullet-resistant laminated materials from ballistic fabric with shielding properties, and can be used in the manufacture of mass protection.

Known resistant to penetration textile fabric (RF Patent No. 2525809, published: 08/20/2014, bul. No. 23), containing at least one untwisted high-strength filament, which is selected from the group consisting of aramid filaments, filaments of polybenzoxazole, filaments from polybenzothiazole or from a mixture of at least two of the above-mentioned filaments, measured without twisting according to ASTM D-885 tensile strength of at least 1100 MPa. The high-strength filament yarn is so much increased in volume high-strength filament yarn that the textile fabric (I) containing this increased high-strength filament yarn has a relative compressibility measured according to DIN 53885, to determine which the initial thickness was measured with a measuring pressure of 0.5 N / cm ² and a final thickness with a measuring pressure of 5 N / cm ² , and the relative compressibility is f times greater than the relative compressibility of the comparative textile fabric, the production of which differs from the production of a penetration-resistant textile fabric (I) only in that the high-strength the filament of the comparative textile fabric is not expanded, with f being from 1.2 to 5.

Also known is a bullet-resistant material (RF Patent No. 2430327, published: 09/27/2011, bul. No. 27), treated with a fluorocarbon polymer, while the treated ballistic fabric has a cured epilam coating on the surface, obtained by immersing the fabric in a solution based on an organic solvent containing 0.2-5 wt. % of a fluorocarbon polymer with an end group - CF3, selected from the group: perfluoropolyester acid, perfluorolauric acid, followed by drying and curing it. Bullet-resistant material is made from layers of ballistic fabric, the fabric is pretreated with a fluorocarbon polymer to obtain a cured epilam coating on the fabric surface by immersing the fabric in a solution based on an organic solvent containing 0.2-5 wt. % of a fluorocarbon polymer with an end group - CF3, selected from the group: perfluoropolyester acid, perfluorolauric acid, followed by drying and curing it.

Also known is a method of obtaining ballistic fabric for the manufacture of bullet-resistant material and bullet-resistant material (RF Patent 2701717, published: 09/30/2019, bul. No. 28) from layers of ballistic fabric based on high-strength aramid threads with a linear density of 29.4 tex, made with twill weave, which is obtained by processing the threads of the fabric by immersing the fabric in a 1N solution of monochloroacetic acid in distilled water, holding in it with subsequent washing, sizing the threads of the fabric by immersing it in a 2-5% solution of polyvinyl alcohol in distilled or demineralized water, followed by holding in it, drying before evaporation of the solvent, treatment with a catalyst - 20-40% sulfuric acid solution, washing from the catalyst and drying to an air-dry state.

In addition, there is a known method of metallization of flat materials (RF Patent No. 2479681, published: 20.04.2013, bulletin No. 11), which consists in melting metal wires by electric action, as well as in spraying microparticles of molten metal onto the plane of the material. The technology is feasible in any environment, including liquid, the canvases have shielding properties, antibacterial, antiviral, catalytic activity.

Also known is an anti-fragmentation explosion-proof device (Application: 94041300/02, 11.11.1994, publication date of the application: 20.04.1997), including a frame, a protective screen, a mass for braking fragments, characterized in that it is equipped with a hemispherical screening dome with a tapered cardboard frame and a central hole, and between the 25th and 26th layers in the middle of the protective screen there is a built-in "pillow" located opposite the central hole and overlapping it in a ratio of 10: 1, while the mass for braking the fragments is made of TSVM-J tissue scraps according to TU 17 RSFSR 62-10540-83, GOST 20566-75, with which in a chaotic free form the shielding dome is filled with a thickness in relation to the mass of the explosive as 1.1: 1 and the "pillow" as 1.3: 1, the diameter of the central hole is as 1: 1, the walls of the dome with a conical cardboard frame at its base are removed from the explosive product as 1: 1.2 in relation to the speed of the fragments expansion, and the area of the protective screen is 2.5 times larger area covered by a hemispherical shielding dome.

Known device for a collapsible explosion localizer (RF patent 2564463, IPC F42D 5/04, publ. 10.10.2015) in the form of a square in terms of formed by four vertical rigid hollow walls made in the form of folding flaps filled with energy dissipating filler and equipped with loops for operational isolation of explosive devices.

Known folding shelter for masking objects and isolation of radio-controlled explosive devices (RF patent 70358, IPC F41H 3/00, publ. 20.01.2008), containing a protective coating made of flexible radio-absorbing materials with resistive properties, and mounting devices for fixing it over the object ... The folding shelter has the shape of a tent, painted in a khaki color, and the broken side surface of the shelter consists of edges directed at an angle to each other, expanding to the bottom, the edges of which are formed with the help of mounting devices, and the surfaces of the edges are not parallel to any of the surfaces of the object, but the width each of the faces is selected to be greater than the maximum length of the electromagnetic wave of the working radio range.

Known folding shelter against remote initiation of cumulative grenades (RF patent 2204790 IPC F41H 5/00, publ. 20.05.2003), which contains curtains made of metal mesh with various mesh sizes and a steel screen with a thickness of at least 0.5 bullet caliber. The steel screen has a super hard face layer with a hardness of at least 85 HRA, the thickness of which is 0.3-0.7 of the total thickness of the screen.

There is a known device for a folding protective and camouflage screen (RF patent 2476810, IPC F41H 3/00, priority 31.01.2009), which is a folding shelter for operational isolation of radio-controlled explosive devices, consisting of a flexible complex coating placed on a transformable collapsible frame, having a layered structure , the upper layer of which is loosely, without fastening, laid on the lower layer, made of a camouflage material, and the lower layer is made of strips of wire braided metal mesh fastened to each other by means of flexible loops, edged around the entire perimeter with a flexible and durable material, while the metal mesh is made with a mesh size of not more than 30 mm made of wire with a thickness of not less than 2.5 mm with a mass of not less than 3.0 g / m. The edging along the general perimeter of the metal mesh with a flexible material with fixed lugs provides the possibility of its deployment (rolling), without interlocking, and the fastening of the strips to each other when assembling the protective element of the flexible complex coating on the frame, which reduces the time of the working installation of the screen.

Closest to the claimed technical solution is US 2006/0011054 A1. According to this solution, a multilayer flexible screen is proposed, consisting of a layer of protection against radio frequencies and a layer of ballistic control.

The difference between the claimed utility model is that the anti-fragmentation shielding fabric, including a structure containing an interconnected layer of anti-fragmentation ballistic fabric and a layer in the form of a material with shielding properties, while the layer of material with shielding properties contains a mesh with a cell size less than a quarter of the wavelength in radio range, where the control of the VU is most likely.

Moreover, you can use several layers with different sizes. The fact is that the efficiency of shielding at different frequencies depends on the size of the cell and the material used to make the shielding mesh (fabric) (https://studopedia.ru/5_887_ekranirovanie-tehnicheskih-sredstv-i-pomeshcheniy.html). Using several layers with different cell sizes and materials (having previously calculated the optimal values), they provide maximum shielding in the widest possible frequency range (from 3 MHz to 30 GHz, for example, https://vandex.ru/search/?text=%D0% B4% D0% B8% D0% B0% D0% BF% D0% B0% D0% B7% D0% BE% D0% BD% D1% 8B% 20% D1% 87% D0% B0% D1% 81% D1% 82% D0% BE% D1% 82% 20% D0% BD% D0% B0% D0% B7% D0% B2% D0% B0% D0% BD% D0% B8% D1% 8F & 1r = 213 & clid-2256802-101 & win = 377).

Thus, the claimed combination of essential features is not known from the prior art.

And this solution will have significant advantages over US 2006/0011054 A1. So, in this patent is indicated "a layer having the properties of electromagnetic shielding" specified in the patent (US 2006/0011054 A1, publ. 19.01.2006).

Obviously, when using a layer in the form of a grid, instead of, for example, a layer in the form of a sheet of steel - when using a grid, the manufacturer wins at least in mass.

So, for example, almost all modern manufacturers of products requiring reliable shielding use this principle - "a metal mesh with a cell size less than a quarter of the radiation wavelength" - For example, manufacturers of EMMI covers - https://aliexpress.ru/item/32907407559 .html? af = 15423_1 & utm_campaign = 15423_1 & aff_platform = api & utm_medium = cpa & cn = 42qhk0z5tttuoi7mhh6burnhax6bwi8i & dp = v5_42q№0z5tttuoi7mhh6burnhax6bwi8i & cv = 3738162 & product_id = 32907407559 & sk = _dUDwK1w & aff_trace_key = 08e2661483024b86a566ed2bed069571-1601608434666-01380-_dUDwK1w & terminal_id = 4a5326c274704e6984e07bcd88488f1c & utm_source = epn & utm_content = 3738162.

Thus, summing up the above, we can state:

When using the above mesh (s), the problem of "too large mass" of products made using a layer with electromagnetic shielding properties is solved.

Also, the use of shielding nets with certain mesh sizes in the claimed anti-splinter shielding fabric provides additional protection in the form of an anti-splinter effect and will contribute to the delay of large, medium and even small fragments (depending on the size of the cell.

In addition, an additional result will be "flexibility in the choice of ranges and maximum attenuation" (as opposed to US 2006/0011054 A1). So, the manufacturer or explant of this product can adjust the efficiency of the shielding range due to the number of meshes used and the size of their cells (for example, if 55 dB is enough in the 800-1000 MHz range, it is enough to use one layer "HEG03 55 dB shielding mesh" (http: // izlucheniya .ru / shop / heg03-setka-ekraniruyushhaya-55db /), to achieve an attenuation of 80 dB, it will be necessary to add another layer of such a grid, for, for example, effective shielding in the 5-6 GHz range, it is necessary to add another layer with smaller linear dimensions of the cells etc.

The technical result consists in increasing the level of safety of those around (since, for example, even when the VU is triggered under the anti-fragmentation shielding fabric, due to the impossibility of "shielding" the signal with a probability of 100%, the anti-fragmentation layers will significantly reduce the damage caused).

The technical result is achieved due to the fact that when covering a possible VU with an anti-fragmentation shielding cloth containing one or more layers of specially designed shielded fabric (mesh), a signal in a wide range of radio frequencies (for example, from 3 MHz to 30 GHz), (including in In this range, cell phones, which are most often used by criminals recently to initiate an IU), will be weakened by several tens of times (up to 10 to the 12th power), which with a high degree of probability will not allow remote detonation of an IU.

The anti-fragmentation shielding fabric includes an interconnected layer of anti-fragmentation ballistic fabric and layers in the form of a material with shielding properties, which is a set of shielding nets. The mating can be achieved, for example, by stitching or securing around the perimeter of the fabric. Radiation of radio waves is the process of excitation of traveling electromagnetic waves of the radio range in the space surrounding the source of current or charge oscillations. Accordingly, the grid cell size for the best shielding should be less than a quarter of the radiation wavelength.

For example, the frequency of the wireless communication system (Wi-Fi) is 2412 MHz, that is, the WiFi wavelength = 12 cm and, accordingly, for maximum shielding of this type of radio signal, the mesh cell size should be less than 3 cm. Thus, the higher the frequency, the smaller should be the linear dimensions of the cell used for shielding.

The most applicable for communication (in terms of stability and efficiency) is the range for radio communication from 30 MHz to 6 GHz. Accordingly, the wavelengths for this range will be from 10 m to 5 cm. The effectiveness of magnetic shielding depends on the frequency and electrical properties of the shield material. The lower the frequency, the weaker the screen acts, the thicker it must be made to achieve the same screening effect. For high frequencies, starting from the medium wave range, a screen made of any metal with a thickness of 0.5-1.5 mm works very effectively. When choosing the thickness and material of the screen, one should take into account the mechanical strength, rigidity, corrosion resistance, the convenience of joining individual parts and making transitional contacts with low resistance between them, the convenience of soldering, welding, etc. (http://www.bnti.ru/showart .asp? aid = 985 & lwl = 04). The choice of the material of the screening mesh is carried out on the basis of ensuring the required screening efficiency in a given frequency range under certain restrictions. These limitations are associated with the weight and size characteristics of the screen, its effect on the shielded object, with the mechanical strength and resistance of the screen against corrosion, with the manufacturability of its design, etc. Screening factors are given in the table.

To achieve the technical result declared in this utility model for frequencies above 10 MHz, copper and, especially, silver film with a thickness of more than 0.1 mm gives a significant shielding effect. Therefore, at frequencies above 10 MHz, it is quite acceptable to use screens made of foil-clad getinax or other insulating material with a copper or silver coating applied to it.

When multilayer screens are used, the magnetostatic screening efficiency is increased.

The use of shielding nets with certain mesh sizes in the claimed anti-splinter shielding fabric provides additional protection in the form of an anti-splinter effect and will contribute to the retention of large, medium and even small fragments (depending on the size of the cell).

Anti-splinter shielding fabric works as follows.

When a possible VU is covered with an anti-fragmentation shielding fabric containing one or more layers of a specially designed shielding mesh, a signal in a wide range of radio frequencies (for example, from 3 MHz to 30 GHz), (including cell phones, which are most often used criminals in recent years for the initiation of VU) is weakened by several tens of times (up to 1012), which with a high degree of probability does not allow remote detonation of the VU. When using the screening mesh "HEG03 screening mesh 55dB" (http://izlucheniya.ru/shop/heg03-setka-ekraniruyushhaya-55db/) at frequencies corresponding to the frequencies of the GSM 900 ), the attenuation will be 55 dB (316000 times in power). When using two layers of this material, the attenuation increases to 80 dB (100,000,000 times in power). Other materials listed in the table have approximately the same characteristics.

The shielding efficiency, which depends on the frequency, material, thickness and linear dimensions of the shielding mesh cell, can be determined by the formula:

where r is the radius of the mesh wire, s is the mesh step, λ is the radiation wavelength.

Example. For GSM (900 MHz), a screening grid was calculated. Center frequency f: 900 MHz. Mesh wire diameter d: 1.5mm. Permissible seepage loss p: 1%. Maximum screen mesh size b: 4.6 mm. Signal loss due to leakage through the grid: -0.04 dB.

In the event of a detonation of an explosive device, an anti-fragmentation product will reduce the damage from such an explosion.

Claims (5)

1. An anti-fragmentation shielding fabric comprising a structure containing an interconnected layer of anti-fragmentation ballistic fabric and a layer in the form of a material with shielding properties, while the layer of material with shielding properties contains a mesh with a cell size less than a quarter of the wavelength in the radio range, where the control of the explosive device. 2. An anti-fragmentation shielding fabric according to claim 1, characterized in that, as a layer of material with shielding properties, it can contain a set of shielding nets with cells of different sizes. 3. Anti-splinter shielding fabric according to claim 1, characterized in that the effectiveness of the shielding is determined by the formula:

where r is the radius of the mesh wire, s is the mesh step, λ is the radiation wavelength.