Method And Apparatus For Protecting Against Ballistic Projectiles

Abstract

A composite material comprising a multitude of masses and fibers supported on a flexible substrate arranged in a manner to absorb energy from a ballistic projectile and thereby protect persons or property from ballistic injury or damage. An array of small, tough disc-like masses are suspended in a three dimensional cradle of high-tensile elastomeric fibers such that energy from an incoming ballistic projectile is first imparted to one or more masses and the motion of the masses are restrained by tensile strain of elastomeric fibers substantially in the direction of travel of the incoming projectile. The projectile is eventually decelerated to harmless velocity through a combination of transfer of momentum to the masses and the elastic and plastic tensile deformation of the fibers. One or more layers of the composite material can be assembled to form body protective armor (“bullet-proof vest”) or property protective armor, the number and characteristics of the layers being adjusted according to the specific ballistic threat anticipated.

Description

BACKGROUND—FIELD OF INVENTION[0001]The present invention is in the field of protection of persons or property against kinetic missiles such as firearm bullets, specifically contemplated is application as ballistic body-armor (or “bullet-proof vests”) and also the protection of vehicles, including aircraft, and sensitive property such as communications equipment by providing flexible, light-weight protection against small arms and high-velocity rifle bullets.BACKGROUND—DESCRIPTION OF PRIOR ART[0002]The mechanical challenges of arresting a high velocity projectile have focused prior and current art on materials with extreme mechanical properties. The practical problem is that the kinetic energy of a high velocity ballistic projectile is high while the cross section is small, resulting in a very high specific energy upon initial impact. Under such conditions, inertial forces typically dominate over mechanical properties and the projectile will tend to punch through a layer of material ...

AI Technical Summary

Benefits of technology

[0017]The method of the present invention differs from prior art first in that a mass of tough material is used not in an attempt to directly block the projectile, nor to deflect it, but to couple mass to it, and thus slow it down by transfer of kinetic energy. This process then may be repeated in sequential stages, whereby additional mass is coupled progressively to the projectile, causing more and more kinetic energy to be transferred from it.

[0018]Second, the method provides a method of restraining the motion of the coupled masses and projectiles, using a network of fibers. The fibers are constructed into a three dimensional arrangement which allows the fibers to elongate elastically or plastically under favorable mechanical conditions so that they exert a progressive restraining force.

[0019]The nature of the restraining force is also of novel design in the present invention, being of two combined sources. First, the fibers stretch and provide restraint due to their own tensile modulus. Second the fibers couple force to surrounding adjacent masses, causing these masses also to experience acceleration, and thereby coupling kinetic energy from the projectile to surrounding masses which are themselves not necessarily directly impacted by the projectile.

[0020]The manner in which energy is coupled to adjacent masses is by tensile loading of the fibers substantially in the direction of the fibers longitudinal axis and substantially in the direction of the projectile prior to impact. T

Problems solved by technology

The practical problem is that the kinetic energy of a high velocity ballistic projectile is high while the cross section is small, resulting in a very high specific energy upon initial impact.

Solid plate designs are inflexible, and often heavy.

Information on these materials and their application to ballistic armor is widely available in the literature, though specific details are not always accessible due to proprietary nature of some materials.

Practical use in protective body armor of solid plate material is commonly restricted to small critical protection

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