RU2732894C1 - Bullet-proof roller shutters - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to design of bullet-proof roller shutters (louvres) and, in particular, can be used in design of bullet-proof collapsible doors, which roll as louvres or roller shutters. Bulletproof shutters include vertical guides, a drum with a drive for winding the web, which consists of hollow lamellae in the form of a flattened profile with hooks and an inner cavity, in which there is a metal insert made of steel with hardness in range of 40–60 HRC, and the distance from the lower edge of the lamellae to the lower hook is 5–30 % of the width of the lamellae.

EFFECT: technical result, which is achieved when realizing the present invention, is to produce roller blinds having given bulletproof properties over their entire area by providing reliable coverage of the entire protected area with armour inserts.

1 cl, 1 dwg, 2 tbl

Description

The invention relates to the construction of bullet-resistant roller shutters (blinds) and, in particular, can be used in the construction of bullet-resistant folding doors, which roll up into a roll of the type of blinds or roller shutters.

Known roller shutters (blinds) described in RF patent No. 4775 (RF patent for utility model No. 4775, published on 08.16.1997), the lamellas in which are made in the form of a double-walled truncated hollow cylinder, the upper and lower hooks have a hook-shaped profile and are directed oppositely, and lamellas are made of non-metallic shockproof material. The lamella cavity is filled with either heat-insulating material or armor inserts.

The disadvantage of these roller shutters is the presence of unprotected zones in terms of bullet resistance. Because the upper and lower hooks are located at the ends of the lamellae, then the armor inserts of adjacent lamellas do not form an overlap, and the movable hinge joint of two adjacent lamellas is not overlapped by the armor inserts in any way. Thus, this design of roller shutters does not provide bullet resistance over the entire area of the leaf. Another disadvantage is the unregulated mechanical properties and geometric shape of the armor insert.

Known roller shutters (blinds), described in the patent of the Russian Federation No. 2039866 (patent for the invention of the Russian Federation No. 2039866, published on July 20, 1995), in which the lamellas are made of aluminum tape rolled into a hollow section having inner and outer walls, as well as the upper and lower hook-and-socket hooks, in which the aluminum tape is arranged in two layers, and the hollow section has at least one contact point, in which the two layers of the aluminum tape are rigidly connected to each other.

The disadvantage of these roller shutters is the presence of unprotected zones in terms of bullet resistance. Because the upper and lower hooks are located at the ends of the lamellae, then the armor inserts of adjacent lamellas do not form an overlap, and the movable hinge joint of two adjacent lamellas is not overlapped by the armor inserts in any way. Thus, this design of roller shutters does not provide bullet resistance over the entire area of the curtain. Another disadvantage of this lamella design is the presence inside the hollow section of at least one point of contact, in which two layers of aluminum tape are rigidly connected to each other, which does not allow placing an armor insert at the contact point, and, accordingly, provide bullet resistance. Another disadvantage is the unregulated mechanical properties and the geometric shape of the armor insert.

Known roller shutters (blinds) described in RF patent No. 104609 (RF patent for utility model No. 104609, published on 05/20/2011), in which the lamellas are a hollow polymer flattened profile, along the longitudinal edges of which elements are made that form a movable connection with adjacent lamellas ... The profile has a polygon in cross-section, the shape of which is close to the shape of a trapezoid, the smaller base of which is arcuate inward, and the larger base, which forms the front wall, is corrugated. On the facing walls of two adjacent lamellas, there is a longitudinal groove on one lamella and a longitudinal ridge corresponding to it on the other lamellae, which form a locking joint when in contact. The design of the lamellas allows you to place an armor insert in the inner cavity, but does not allow for the location of the armor inserts of two adjacent lamellas overlapping.

Thus, this design of roller shutters does not provide bullet resistance over the entire area of the curtain.

Known bulletproof roller shutters presented on the Russian market by the company "WIRAL" (www.wiral.ru), which were chosen by the authors as a prototype. These roller shutters include vertical guides, a drum with a drive for winding a web consisting of hollow lamellas in the form of a flattened profile with upper and lower hooks, in the inner cavity of which a metal insert is made.

The metal insert (armor insert) in its section has a complex geometric shape with several horizontal projections. This shape of the insert has different thicknesses at different points of the section. If bullet resistance is ensured by the minimum section thickness, then an increase in thickness in other sections of the section leads to an increase in the mass of the liner and, accordingly, of the lamella, which, in turn, leads to an increase in the load on the drive and a decrease in the functional characteristics of the roller shutters. If bullet resistance is ensured by the maximum section thickness, then thinner section zones will not provide bullet resistance.

A significant disadvantage of the prototype is that the metal insert is made of aluminum, the hardness of which is significantly lower than the hardness of the core of any bullet. Thus, bullet resistance in the prototype is achieved not due to the mechanical properties of the armor insert, but only due to its thickness. The WIRAL company has a declared bullet resistance class Br1 in accordance with GOST R51112-97. Bullet resistance in a higher class cannot be ensured, since the inner cavity of the lamella does not allow placing a thicker armor insert.

Another disadvantage of these roller shutters is the unregulated arrangement of the lower hook, which sets the amount of overlap of the armor inserts of two adjacent lamellas and, accordingly, the bullet resistance of the lamella joint zone.

The bullet-resistant roller shutters declared by the authors include vertical guides, a drum with a drive for winding a cloth consisting of lamellas. Each lamella (see Fig. 1) is a flattened profile with upper 3 and lower 4 hooks. In the inner cavity of the lamella 1 is made of a metal equal-thickness rate of steel 2. The lower hook 4 is located at a distance A from the lower edge of the lamella.

The aim of the invention is to obtain roller shutters with specified bulletproof properties over their entire area.

The technical result of the invention is achieved by choosing an equal-thickness steel with a hardness of 40-60 HRC as a material for the armor insert, as well as by choosing a distance from the lower edge of the lamella to the lower hook of 5-30% of the width of the lamella, which ensures guaranteed overlapping other armor inserts from adjacent lamellas, and also provides the ability to wind the cloth on the drum without damaging the lamellas. Fulfillment of these two conditions provides guaranteed bullet resistance for a given class and high functional characteristics.

The guaranteed efficiency is achieved when choosing an equal thickness steel with a hardness of 40-60 HRC as the material of the armor insert. The uniform thickness of the armor insert provides the same degree of protection throughout its entire area.

If the hardness of steel is below 40 HRC, then bullet resistance is ensured not due to the mechanical properties of the liner, but due to its thickness. This leads to an increase in the weight of the product, as well as the load on the drive and the hooks of the lamellas when winding on the drum. Also, if a bullet hits a liner with a hardness below 40 HRC, its plastic deformation may occur, which will lead to deformation and damage to the lamella profile, which, in turn, will lead to disruption of the clutch assembly of two adjacent lamellas and the product as a whole.

If the hardness of the steel is above 60 HRC, then brittle destruction of the material occurs when a bullet hits. Even if the thickness of the liner is large, when a bullet hits, the material will begin to crumble, and penetrations may occur. Also, when a bullet hits, a back spall is possible, which is a secondary damaging element.

An armored insert of equal thickness steel with a hardness of 40-60 HRC has sufficient strength and ductility to ensure bullet resistance without plastic deformation of the insert and without the formation of secondary damaging elements.

Guaranteed efficiency is achieved when the distance from the lower edge of the sip to the lower hook A is 5-30% of the width of the sipe L.

When the distance from the lower edge of the lamella to the lower hook A is less than 5% of the width of the lamella L, the armor inserts of the adjacent lamellas do not overlap or form insufficient overlap, thereby creating an unprotected area in terms of bullet resistance.

In the case when the distance from the lower edge of the lamella to the lower hook A is more than 30% of the width of the lamella L, the adjacent lamellas when winding on the drum are located relative to each other at angles of more than 60 °. In this case, each layer of the web on the drum exerts pressure on the lower layers, and the entire load falls on the hooks, which leads to their deformation. When the angles of rotation of adjacent lamellas relative to each other are more than 60 °, their disengagement is possible, which leads to the failure of the roller shutter.

Also, when the distance A is more than 30% of the width of the lamella L, too much overlap of both the armor inserts of the adjacent lamellae and the lamella profiles is provided, which leads to a significant increase in the mass of the roller shutters, which, in turn, leads to an increase in the load on the drive, a decrease in functional characteristics, reducing the service life and increasing the cost of the product.

In order to reduce the mass of the roller shutters with unchanged bullet-proof properties, the insert located in the hollow section of the lamella can be made of a high-modulus polymer material.

In order to reduce the cost of the product, the lamella can be made of polymer material. This will lead to a decrease in the weight of the product, its cost, but will not in any way affect the bullet-resistant properties of the roller shutters.

For testing, a roller shutter frame was made, which includes vertical guides and a drum with a drive for winding the canvas. This frame was fixed to the test bench in an upright position. A series of samples of lamellae were made in the form of a flattened profile with hooks and an internal cavity in which a metal insert was made in the form of a flat equal-thickness steel strip. The variable parameters in the samples are the hardness of the steel insert and the distance from the lower edge of the lamella to the lower hook (as a percentage of the width of the lamella). The characteristics of all lamella samples are shown in Table 1. Thus, each test sample was prepared by mounting a certain type of lamella on a roller shutter frame. After installing the lamellas, each sample was a complete roller shutter assembly.

Steel 43KHSNMA (SPS-43) was chosen as the material of the metal insert. Different ranges of hardness are obtained using different heat treatment modes.

The thickness of the steel insert for all tests was selected to be 6.7 mm.

In the testing center for special materials of ZAO NPO SM (accreditation certificate No. ROSS RU.0001.22C308 dated August 26, 2014), each sample was tested for bullet resistance in accordance with GOST R 51112-97.

The tested bullet resistance class is Br4 according to GOST R 51112-97.

Test equipment: "Trassa" stand; bullet speed recorder RS-4M No. 664, psychrometric hygrometer VIT-1 No. R116 (29), AK-103 assault rifle of 7.62 mm caliber No. 101360369, ind. 57-N-231 with a PS bullet with a heat-strengthened steel core, a control screen made of cardboard, 1.0 mm thick.

Test conditions: firing distance - 10 m, air temperature plus 19 ° С, bullet meeting angle 90 °, bullet speed 720 ± 15 m / s.

The shelling was carried out from the front side of the roller shutters. In each sample, two shots were fired: one - in the central part of the lamella, one - in the area of the junction of two lamellas.

After shelling each sample, it was examined to determine the nature of the defeat.

The sample is considered to have passed the test if there is no through penetration of the sample and there are no traces of penetration of the witness screen by secondary striking elements.

The results of tests for bullet resistance are shown in Table 2.

It can be seen from the test results that only samples No. 3 and No. 6 have successfully passed the tests and correspond to the bullet resistance class Br4 according to GOST R 51112-97. But in sample No. 6, the distance from the lower edge of the lamella to the lower hook A is 40% of the width of the lamella L, so the adjacent lamellae, when wound on the drum, are located relative to each other at angles of more than 60 °. In this case, each layer of the web on the drum exerts pressure on the lower layers, and the entire load falls on the hooks, which leads to their deformation. Also, when the angles of rotation of adjacent lamellas relative to each other are more than 60 °, they may come out of engagement, which leads to the failure of the roller shutter. Moreover, the distance from the lower edge of the lamella to the lower hook A of 40% of the width of the lamella L led to a significant increase in the mass of the roller shutters, which, in turn, led to an increase in the load on the drive and an increase in the cost of the product. Therefore, guaranteed efficiency is achieved only in sample # 3. This sample corresponds to the class of bullet resistance Br4 according to GOST R 51112-97, which is significantly higher than in the product according to the prototype.

Thus, the action of the claimed parameters of the invention made it possible to achieve the claimed technical result - obtaining roller shutters with specified bulletproof properties over the entire area.

The claimed technical solution for the design features of bullet-resistant roller shutters is new, since the set of distinctive features of the invention, including in particular cases, is unknown from the literature and practical experience in this area.

The solution meets the criterion of "inventive step", since the proposed one does not follow explicitly for a specialist from the analysis of domestic and foreign prior art.

Claims (2)

1. Bullet-resistant roller shutters, including vertical guides, a drum with a drive for winding a web, consisting of hollow lamellas in the form of a flattened profile with hooks and an internal cavity in which a metal insert is made, characterized in that the metal insert is made of equal thickness from steel with hardness in the range of 40-60 HRC, and the distance from the lower edge of the lamella to the lower hook is 5-30% of the width of the lamella. 2. Roller shutters according to claim 1, characterized in that the lamella is made of polymer material.

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