Helmets for protection against rifle bullets
AssigneeHoneywell International Inc.
InventorsAshok Bhatnagar, Bradley L. Grunden, Brian D. Arvidson, Lori L. Wagner
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Abstract
A helmet shell is formed having an outer section of fibrous layers, a middle section of fibrous layers and an inner section of fibrous layers. The outer section layers contain high tenacity abrasive fibers in a resin matrix. The middle section layers contain high strength polyolefin fibers and are in the form of woven or knitted fabrics with a resin matrix. The inner section layers contain high strength polyolefin fibers and are in the form of non-woven fabrics with a resin matrix. The helmet is lightweight and resists penetration of rifle bullets.
Claims20
A lightweight molded helmet that is resistant to penetration by rifle bullets, said helmet comprising a shell, said shell comprising from the outside to the inside:
- a first plurality of fibrous layers, said fibrous layers comprising high tenacity abrasive fibers impregnated with a first resin matrix;
- a second plurality of fibrous layers attached to said first plurality of fibrous layers, said second plurality of fibrous layers comprising a woven or knitted network of high tenacity fibers impregnated with a second resin matrix, said high tenacity fibers comprising polyolefin fibers;
- and
- a third plurality of fibrous layers attached to said second plurality of fibrous layers, said third plurality of fibrous layers comprising a non-woven network of high tenacity fibers impregnated with a third resin matrix, said high tenacity fibers comprising polyolefin fibers.
A lightweight molded helmet that is resistant to penetration by rifle bullets, said helmet comprising a shell, said shell comprising from the outside to the inside:
- a first plurality of fibrous layers, said first plurality of fibrous layers comprising a woven network of high tenacity glass fibers impregnated with and fully embedded in a first resin matrix, said first resin comprising a thermosetting resin;
- a second plurality of fibrous layers attached to said first plurality of fibrous layers, said second plurality of fibrous layers comprising a woven network of high tenacity fibers impregnated with and fully embedded in a second resin matrix, said high tenacity fibers comprising polyethylene fibers, said second resin comprising a thermosetting resin or thermoplastic resin;
- and
- a third plurality of fibrous layers attached to said second plurality of fibrous layers, said third plurality of fibrous layers comprising a non-woven network of high tenacity fibers impregnated with and fully embedded in a third resin matrix, said high tenacity fibers comprising polyethylene fibers, said third resin comprising a thermoplastic resin,
- said helmet having a total areal density of from about 3 to about 5 pounds per square foot (14.6 to 24.4 kg/m2), and is resistant to rifle bullets having energies of at least about 1600 joules.
A method for forming a shell of a lightweight helmet that is resistant to penetration by rifle bullets, said method comprising the steps of:
- supplying a first plurality of fibrous layers to a mold, said fibrous layers comprising a network of high tenacity fibers impregnated with a first resin matrix, said high tenacity fibers comprising abrasive fibers;
- said first plurality of fibrous layers facing inwardly in said mold;
- supplying a second plurality of fibrous layers to said mold, said second plurality of fibrous layers comprising a woven network of high tenacity fibers impregnated with a second resin matrix, said high tenacity fibers comprising polyolefin fibers, said second plurality of fibrous layers overlying said first plurality of fibrous layers, said first and second resins being compatible such that said first and second plurality of fibrous layers are bondable to each other;
- supplying a third plurality of fibrous layers to said mold, said third plurality of fibrous layers comprising a non-woven network of high tenacity fibers impregnated with a third resin matrix, said high tenacity fibers comprising polyolefin fibers, said third plurality of fibrous layers overlying said second plurality of fibrous layers;
- and
- applying heat and pressure to said first plurality of fibrous layers, said second plurality of fibrous layers, and said third plurality of fibrous layers to thereby form said helmet shell.
Dependencies are inferred from the claim text.