Ballistic Fabric

Abstract

Briefly the invention relates to a flexible fabric for use as for example in a roll-up shutter with improved ballistic properties. More specifically, the present invention is directed to a ballistic fabric that is formed from a unique cabled yarn and allows less deformation on impact. The unique cabled yarn may be a metal reinforced aramid yarn for giving the fabric additional strength.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims priority benefits of U.S. Provisional Patent Application Ser. No. 60 / 874,108 filed Dec. 11, 2006 entitled “Ballistic Fabric”, the disclosure of which is incorporated herein by reference.BACKGROUND[0002]1. Field of the Invention[0003]This invention relates generally to flexible fabrics with improved ballistic properties. More specifically, the present invention is directed to a ballistic fabric that is formed from a unique cabled yarn and allows less deformation on impact.[0004]2. Background Discussion[0005]In south-east states like Florida and Louisiana, there is a need for protecting the openings of buildings such as windows and doors and other means of access, especially after looking at the aftermath of Hurricanes Charlie and Katrina. Often times such openings are covered with breakable glass, and during a storm when a loose object, such as a tree limb or the like, is blown into the glass covering the opening, th...

AI Technical Summary

Benefits of technology

[0017]Briefly the invention relates to a flexible fabric, for example a roll-up shutter with improved ballistic properties. More specifically, the present invention is directed to a ballistic fabric that is formed containing unique cabled yarns. The unique cabled yarn may be a metal reinforced aramid yarn giving the fabric additional strength, and allowing less impact deformation.

Problems solved by technology

Often times such openings are covered with breakable glass, and during a storm when a loose object, such as a tree limb or the like, is blown into the glass covering the opening, there is a danger that people within the building will be injured or killed by the flying glass.

For example, the states along the Gulf of Mexico, during certain times of the year, are prone to enormous and deadly storms known as hurricanes.

Most of the damage in hurricanes is caused by the air blowing into the premises through the broken windows and shutters, which then lifts off the roof and can cause the plant or house to collapse.

Rolling doors of this type can be moved only slowly because they have mechanical hinges and produce unwanted, sometimes shrieking noises when they are moved.

These rolling doors are susceptible to damage during everyday operation, particularly due to impacts from vehicles, such as, stacker trucks.

The repair of the damage is complicated because deformed pans, such as, steel lamellas, are difficult to replace.

However, the major disadvantage of these high-speed doors is the necessary complicated mechanism because the highly flexible materials used in the doors are not capable of transmitting thrust or pushing forces.

This set up, however, is not mechanically stable to withstand the damage caused due to the impact of a hurricane storm.

The curtain in this case also does not have sufficient impact resistance to withstand the colossal impact due to a storm.

This patent discloses that the elements can be formed of either textile or metal fibers, in which case, the closing element is either too flimsy or too stiff and does not provide the essential ballistic properties required in a door closing.

This property, however, is not useful in instances where the debris impacts the building surface at high speeds.

However, as a result of the stranded nature of aramid materials, producing wide width (1-12 m) panels of open mesh designs for protection of large objects like windows for housing, office, or business store fronts is often not feasible.

Yarns produced of aramid strands tend to dimensionally flatten during weaving producing a fabric with little open area / porosity and poor dimensional stability as a result of the lack of crimp in the aramid yarns.

Additionally, aramid yarns are difficult to weave as the individual strands that make up an aramid yarn, while having good tensile strength tend to abrade resulting in continuous breaks across the width during weaving.

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