RU2851385C1 - Protective element - Google Patents

Abstract

FIELD: military affairs.

SUBSTANCE: invention relates to devices for protecting armoured objects from the damaging effect of armour-piercing and shaped-charge anti-tank ammunition. The protection element has a body comprising side walls, a cover and a bottom. The inner surface of the body bottom has a conical shape, and the outer surface of the bottom is convex.

EFFECT: increased efficiency, reliability of functioning and safety for accompanying infantry and tank crew.

1 cl

Description

The invention relates to devices for protecting armored vehicles, primarily tanks.

A well-known technical solution involves a protective element (PE) containing a parallelepiped-shaped housing. Inside the housing are metal plates separated by a layer of explosive (Vorotlin, M.S., Dorofeev, S.V., Knyazeva, L.N., Chukov, A.N., Textbook. Tula: Tula State University, 2003, 168 p.).

EZs are available in wall-mounted and built-in versions.

This technical solution, known since 1942, despite the efforts of specialists, inventors, scientists, and engineers in most countries for many decades, remains ineffective and, moreover, dangerous. When the protective shell is triggered and explodes, it injures friendly infantry with shrapnel, and also destroys, detonates, and detonates several adjacent protective elements on the tank's armor. The simultaneous detonation of several protective elements can also adversely affect the hull, crew, equipment, and instruments. Furthermore, all protective shells can be detonated within seconds by small arms fire, damaging the combat capability of the tank and crew.

Let us accept the above technical solution as an analogue.

A technical solution known as invention No. 2809956 for protecting armored objects from anti-tank munitions is also known. It comprises a massive casing made of high-strength steel capable of withstanding high hydraulic pressure and generating significant braking force of up to several thousand tons when an armor-piercing projectile penetrates the casing (chamber) of the protective element. Therefore, the thickness of the casing walls reaches several centimeters.

We are adopting invention #2809956 as a prototype. Its drawback is the increased cost of the product due to the high cost of high-strength metal and the increased wall thickness of the protective shell casing, which must withstand fluid pressure of up to several thousand atmospheres, which occurs when armor-piercing projectiles (APS) penetrate the protective element. Furthermore, when an armor-piercing fin-stabilized discarding sabot (APFSDS) core, which has a diameter several times smaller than the ammunition caliber, penetrates the protective shell, the hydraulic pressure in the protective shell chamber also increases and its fluid volume decreases, but to a lesser extent than when using an APS or APFSDS projectile. Therefore, the increase in pressure in the protective shell casing will be less pronounced. This reduces the force that causes the protective shell casing and APFSDS core to rotate before impact with the armor. This reduces the effectiveness of the protective device.

The aim of the invention is to eliminate the above mentioned disadvantages.

This goal is achieved by the fact that the inner surface of the bottom of the housing has a conical shape, and the outer surface of the bottom is convex.

Let's consider a specific case of the protection element design, assuming the same housing dimensions as the prototype: side wall length of 300 mm, end faces of 210 x 210 mm. The shape is a parallelepiped. The wall thickness of the components can be significantly reduced compared to the prototype, for example, to 5-10 mm, and ordinary, inexpensive low-carbon steel can be used, since the protection element is not subject to high hydraulic pressure. In fact, the pressure in the protection element's housing chamber is zero.

The installation of the protective element on the tank must be done with a gap between the bottom of the hull and the armor.

Let's consider a case where the inner surface of the housing bottom is cone-shaped. For example, assume that a conical protrusion 200 mm high and with a base radius of R = 80 mm is placed on it. Generally, the protrusion can be shaped like a tetrahedral pyramid with a square base, a truncated pyramid, or a paraboloid of revolution. Generally, the lateral surface of this protrusion can be convex-concave.

We will take the convex protrusion on the outer surface of the bottom of the housing, for example, in the form of a hemisphere with a diameter of 210 mm.

This technical solution significantly increases the effectiveness of protection against the most dangerous anti-tank weapon, the APFSDS, by forcibly breaking the core and rotating the protective shell casing through an angle of approximately 90°, along with the projectile inside. The impact with the flat of the shell hits the armor and therefore does not penetrate it. The kinetic energy of the projectile's movement creates the force that rotates the projectile.

If the core of an armor-piercing, fin-stabilized discarding sabot projectile penetrates the chamber of the casing, its rear portion is pinched in the punctured hole in the casing cover, and the tip, located at the front, is pressed against the side surface of the cone, slides along it, moves, and is pushed toward the side wall of the protective element, inevitably bending. It is important to note that the core material is extremely hard, but brittle. There are cases where it has broken during firing in the gun barrel. The maximum deviation of the front portion of the core from the longitudinal axis of the ammunition is equal to the radius of the base of the cone and is 80 mm. Bending this amount will inevitably result in the curved, pointed front portion of the core breaking off, rendering it unable to penetrate tank armor. The fragments of the core (tip and rear part), flying at a speed of almost 2 km/sec, possessing a significant reserve of kinetic energy, momentum of movement, momentum of force, slide along the side wall of the cone, as if along a guide, and, at the end of the movement, will inevitably be clamped at the base of the cone between its side surface and the side wall of the protective element.

The magnitude of the impact F1 of a core with a protective element can amount to several hundred tons of force. F1 is the force impulse that moves and rotates the protective element. The lever arm of the force F1 is equal to the radius R of the cone's base. When the hemisphere of the base contacts the tank's armor, a fulcrum is created, and the torque M1 = F1 × R causes the protective element to rotate 90°, until the side surface of the protective element contacts the tank's armor.

A combined body T, consisting of a projectile and protective element combined into a single unit, strikes the protected object. Let's assume the weight of the APFSDS core is 5 kg, and the protective element is 30 kg. The projectile's velocity is 1.8 km/sec. According to the law of conservation of momentum, body T will move slower than the APFSDS by a factor equal to the mass of the combined body greater than the mass of the core. With the given parameters, the multiplicity is 7, and the impact velocity on the armor is Vy = 1.8 : 7 = 0.257 km/sec.

There is no fundamental difference in the process of striking an armored target with a BPS, BS, or BOPS.

The armor-piercing discarding sabot projectile is significantly less dangerous than its fin-stabilized counterpart due to its lighter weight. The inventive technical solution poses no threat to a tank.

We'll assume the mass of the armor-piercing projectile is 20 kg. The armor-piercing projectile is also pinned between the side wall and the cone, and, when combined with the anti-aircraft gun, strikes the tank at a safe angle. The proposed technical solution reduces the armor-piercing projectile's velocity by 2.5 times. The armor-piercing projectile poses no threat to the tank's armor.

The proposed protective element performs the following functions: trapping armor-piercing, sub-caliber, and fin-stabilized projectiles; reducing their velocity several times before impacting the armor; and changing the angle of attack of the target to a safe level.

When a shaped-charge projectile is used, its destructive force upon impact with the protective element passes through obstacles: the casing cover, the chamber, the cone, the base, the hemispherical base thickening, and the air gap, which acts as passive protection effectively dispersing the projectile's focus and jet. It is known that increasing the number of obstacles leads to a synergistic effect. Furthermore, the volume of the casing chamber significantly exceeds the volume of the shaped-charge jet, leading to its cooling, turbulence, and destruction. This ensures the effectiveness of the protection provided by the proposed technical solution. If necessary, these obstacles can be supplemented by water, filling, for example, 80% of the protective element's chamber volume.

It has the highest heat capacity of any liquid or solid substance. Water vapor shares this property. Significant cooling of the jet, significant hydraulic braking of its elements, and dispersion of damaging particles by turbulent flows of water and superheated steam guarantee protection of armored vehicles from cumulative damage.

The proposed invention allows for reliable protection of armored vehicles from projectile damage while reducing the cost of the product. This is achieved by using protective elements (PE) whose inner hull bottom surface is cone-shaped and whose outer bottom surface is convex. The PE chamber can be filled with liquid, such as water.

Claims (1)

An element for protecting armored objects from anti-tank ammunition, which has a housing containing side walls, a lid and a bottom, characterized in that the inner surface of the bottom has a conical shape, with the apex of the cone directed upward, and the outer surface of the bottom is convex.