The present invention relates to body armor, and more particularly, to body armor constructed of steel.
Conventional body armor is available in a number of different configurations and materials. For example, conventional, standard issue armor in use by the U.S. military is constructed of a ceramic such as boron carbide. Other conventional materials used to fabricate body armor include ultra high molecular weight polyethylene (UHMWPE), and aramid fibers. While these various materials have various advantages, ceramic armor, which is typically the conventional choice for defeating rifle rounds, has certain disadvantages. For example, ceramic armor plates can typically only survive a limited number of hits before they break apart and become ineffective. Additionally, ceramic armor is relatively fragile, requiring specialized storage and handling procedures. Ceramic armor is thick, often having more than one inch of thickness. Finally, ceramic armor is expensive, which often puts it outside of the budget range of civilians, police, or security agencies with limited budgets.
Steel has long been used in applications requiring ballistic resistance, such as in armor applications. In particular high hardness abrasion resistant steel, for example, AR500 steel (“abrasive resistant steel; 500 Brinell hardness”) has long been used to build bullet traps, shooting targets and as armor plate for vehicles and fixed installations. More recently, AR500, AR550 and AR650 steel has been used to construct body armor. While steel armor is inexpensive and has excellent ballistic resistance, multi-hit capability, and durability, it is heavy and difficult to form. As a result, steel armor plates have typically been offered as flat flats, or at best, single curved plates in which the trauma plate has a curve that is defined about an axis that runs vertically with respect to the torso when the plate is worn. An example of such a single curve steel plate is provided in U.S. Patent No. 9021612. What is needed is a steel armor plate that more naturally matches the contours of the human torso.
The invention relates generally to a steel body armor plate which is curved along multiple axes at least two of which are mutually orthogonal such that the plate is curved about the long axis of the torso of the wearer, as well as least one axis that is orthogonal to the long axis of the torso. Additionally, embodiments of the invention are directed to methods of imparting curves to a hardened steel plate (e.g., AR500, AR550, or AR650) along multiple axes to allow the plate to more naturally conform to the shape of the human torso, in a rapid, inexpensive and low-temperature process.
The Applicant's disclosure relates generally to a multi-curved armor plate and a method of imparting curves to an abrasion resistant steel armor plate along multiple axes to allow the plate to more naturally conform to the shape of the human torso. Further, the Applicant's disclosure includes a ram-and-die arrangement for imparting curves to the abrasion resistant steel armor plate.
In certain embodiments, the multi-curved armor plate is made from ballistic resistant steel and comprises a convex front surface and a concave rear surface. The armor plate further comprises a first end, an opposing second end, a length, a width, a first axis symmetrically disposed along said length, a second axis disposed along said width, a third axis disposed along said width, a trapezoidal portion at said first end, and in combination with an integral rectangular portion extending to said opposing second end.
In further embodiments, the armor plate comprises a first radius of curvature along said first axis, a second radius of curvature along a second axis adjacent said first end, and a third radius of curvature along a third axis adjacent said second end.
Another embodiment illustrates that the ballistic resistant metal has a Brinell hardness of between about 400 and about 600, preferably between about 505 and 515. In yet further embodiments, at least the front surface of the armor plate comprises a spalling resistant coating, which is polyurea elastomer based. Other embodiments are directed to other types of steel, for example, steels having a Brinell hardness of between about 545 and 560 and between about 570 and 670.
In certain embodiments, a method of manufacturing a steel armor plate comprises providing a plate, which is formed from ballistic resistant steel; bending the armor plate to form a cylindrically curved plate longitudinally; and further bending the armor plate to form one radius of curvature widthwise adjacent to one end and another radius of curvature widthwise adjacent to the opposite end.
The shape of the armor plate is further contoured to fit to the shape of the human torso. Two corners from one end of the armor plate are cut to form a trapezoidal portion in combination with an integral rectangular portion extending to the opposite end of the plate. Further, one of the latitudinal radius of curvature is disposed at the long side of the trapezoidal portion.
The method further comprises providing a die and a ram both with a radius of curvature that, during a pressing process, preserves the radius of curvature along the longitudinal axis; placing the plate over the die; and pressing the plate into the die by the ram.
Additionally, the method further comprises coating the plate with a layer of spalling resistant polyurea elastomer based material.
Embodiments of the invention have certain advantages. Steel body armor according to the invention is resistant to penetration from high-velocity rifle rounds, is durable and has multi-hit capability. Additionally, steel body armor according to the invention resists bullet splash or spalling. Additionally, steel body armor according to the invention can withstand rough handling and sub-optimal environmental and storage conditions. A steel body armor plate according to the invention is highly ergonomic, with a first curve that wraps around the torso about the torso's long axis, a second curve that wraps the plate around the top of the chest, which minimizes interference with the chin, and a third curve that wraps the plate around the bottom of the rib cage. The resulting triple-curved plate hugs the rib cage area, resulting in coverage of vital organs and vasculature while hugging the contours of the body.
Methods of fabricating armor plates according to embodiments of the invention have additional advantages. Conventional ceramic body armor plates may be formed into relatively complex shapes by hot pressing boron carbide powder into a die under high temperature, or alternatively, by sintering boron carbide powder. These processes cannot be used for form ballistic resistant steel because heating hardened, abrasion resistant steels like AR500, AR550 and AR650 risks annealing the material, which decreases it hardness and therefore decreases its ballistic resistance. Additionally hot pressing and sintering processes are expensive and time consuming, which eliminates one advantage of steel body armor. In contrast, embodiments of the current invention take preformed plates having a first curve along a first long axis, and use the ram-and-die arrangement to impart a second and a third orthogonal curves, in a low temperature process that does not modify the material properties of the steel.
In certain embodiments, the ram-and-die arrangement comprises a die, which comprises two end plates each having a concave edge with a radius of curvature and a plurality of interior support plates between the two end plates, a ram having a convex curved edge, and a stopper disposed adjacent to one of the end plates. Further, each of the support plates has a center height, where the center heights of the support plates are in a step-down, step-up fashion with respect to the center heights of the two end plates. Moreover, the ram, die, and stopper are arranged such that a curved armor plate's convex front side is supported by the concave edges of the two end plates and is positioned such that a predetermined location on the armor plate is below the convex edge of the ram when the armor plate is placed over the die and against the stopper. The ram-and-die arrangement according to an embodiment of the invention is designed to preserve the first long axis curve in the plate while the second and third transverse curves are imparted in a rapid process.
Additional advantages will become clear upon review of the following detailed description of the preferred embodiments.
The invention will be more fully understood by referring to the following Detailed Description of Specific Embodiments in conjunction with the Drawings, of which:
References throughout this specification to “one embodiment,” “an embodiment,” “a related embodiment,” or similar language mean that a particular feature, structure, or characteristic described in connection with the referred to “embodiment” is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. It is to be understood that no portion of disclosure, taken on its own and in possible connection with a figure, is intended to provide a complete description of all features of the invention.
In addition, the following disclosure may describe features of the invention with reference to corresponding drawings, in which like numbers represent the same or similar elements wherever possible. In the drawings, the depicted structural elements are generally not to scale, and certain components are enlarged relative to the other components for purposes of emphasis and understanding. It is to be understood that no single drawing is intended to support a complete description of all features of the invention. In other words, a given drawing is generally descriptive of only some, and generally not all, features of the invention. A given drawing and an associated portion of the disclosure containing a description referencing such drawing do not, generally, contain all elements of a particular view or all features that can be presented is this view, for purposes of simplifying the given drawing and discussion, and to direct the discussion to particular elements that are featured in this drawing. A skilled artisan will recognize that the invention may possibly be practiced without one or more of the specific features, elements, components, structures, details, or characteristics, or with the use of other methods, components, materials, and so forth. Therefore, although a particular detail of an embodiment of the invention may not be necessarily shown in each and every drawing describing such embodiment, the presence of this detail in the drawing may be implied unless the context of the description requires otherwise. In other instances, well known structures, details, materials, or operations may be not shown in a given drawing or described in detail to avoid obscuring aspects of an embodiment of the invention that are being discussed.
The invention as recited in claims appended to this disclosure is intended to be assessed in light of the disclosure as a whole.
In accordance with preferred embodiments of the present invention, methods and apparatus are disclosed for forming a hardened steel trauma plate such that it comprises at least three curves so that it more naturally conforms to the shape of the human torso.
In the embodiment of
In certain embodiments, the armor plate 100 has a faceted tombstone shape (i.e., a rectangle with cut or rounded corners) including shoulder cutouts at the end 110 of the armor plate 100. In the embodiment of
More specifically, in certain embodiments, the triple-curved armor plate 100 comprises a trapezoidal portion 160, which includes first end 110 as a shorter base, and an integral rectangular portion 170 extending to opposing second end 120. Further, in some embodiments, the trapezoidal portion 160 is an isosceles trapezoid having two base angles 164 and 166 that are equal in measure. Moreover, in some embodiments, altitude 162, which is the distance at right angle from one base, to the other base of the trapezoidal portion 160, is between about ⅓ to ½ of a length 172 of the rectangular portion 170. As described herein, “about” is used to capture the inherent measure errors. In other embodiments, altitude 162 of trapezoidal portion 160 is about equal to length 172 in measure to ensure better arm and shoulder movements and comfort when a user wears the triple-curved armor plate.
Referring now to
Referring to
Referring to
In the embodiment of
The bends about second 220 and third 230 axes create angled upper 270 and lower 275 portions of plate 100. The angle of these upper and lower 270, 275 portions make with approximate central planar portion 265 is approximately 5 degrees, measured along the vertical centerline of plate 110, i.e., along a projection of axis 210. Off of the projection of axis 210, the bends about axes 220, 230 interact with the vertical bend about axis 210 to create a compound angle in angled upper 270 and angled lower 275 portions with respect to approximate planar center portion 265.
In the embodiment of
In certain embodiments, first radius of curvature 212 is greater than second radius of curvature 222 or third radius of curvature 232. Further, second radius of curvature 222 substantially equals to third radius of curvature 232. As described herein, “substantially” means that the two radii of curvature differ from each other within 5% of the length of the radius. More specifically, a curvature defined by second radius of curvature 222 substantially matches another curvature defined by third radius of curvature 232.
In certain embodiments, a curvature defined by radius of curvature 222 or 232 forms about a 5 degree angle with respect to a tangent line 224 (
In embodiments where plate 100 is an 8×10″ plate, the top and bottom bends along axes 220 and 230 are placed about 2.5″ from the top and bottom edges 110, 120 of plate 100. For 10×12″ and 10×14″, the top and bottom bends are placed about 3.25″ from the top and bottom edges of the plate 100.
In certain embodiments, armor plate 100 is formed from AR500 steel, which has a thickness of about 0.25″, but armor plate 100 can also be formed from any other ballistic resistant steel in any thickness capable of defeating a designed for threat. As described herein, “about” is used to capture the internal measure errors. In certain embodiments, ballistic resistant steel having Brinell hardnesses of between about 400 and about 600 is acceptable depending on the application. In certain embodiments, the AR500 steel has a Brinell hardness of between about 495 and about 515, and particularly between about 505 and about 515 is preferred. In other embodiments, plate 100 is formed of AR550 steel having a Brinell hardness of between 545 and 560. In yet other embodiments, plate 100 is formed of AR650 steel having a Brinell hardness of between 570 and 670. In embodiments using AR550 steel, the thickness of the steel portion of plate 100 is again about 0.25″. In embodiments using AR650 steel, which allows for a reduced steel thicknesses to be used, plate 100 has a thickness of about 3/16″.
In the embodiment of
In the embodiment of
The embodiment of
In the embodiment of
A method of manufacturing a triple-curved armor plate 100 using ram-and-die arrangement 500 pictured in
The curved plate with first radius of curvature 212 is placed over die 510 one end at a time with concave back surface facing up toward ram 520 and the convex front surface engaged and supported by the curved surfaces of endplates 705, 710, which have the same radius of curvature 212. The end of curved plate 100 is engaged by a metal stopper 540 (
A first end, for example, end 110 of the curved plate 100 with first radius of curvature 212 is inserted into die 510 and ram 520 presses down on the curved plate to form second radius of curvature 222 along second axis 220 at longer base 168 of trapezoidal portion 160 (
Both the radius of the transverse bend and the position of the transverse bend are adjustable by varying the position of the stopper 540, the lateral position of the ram 520 with respect to end plates 705, 710, the plunge distance 720 and the number of support plates 715a-g between the end plates. In the embodiment of
After the first transverse bend of radius 222 is imparted, the ram returns to its up position, and plate 100 is reversed and the process is repeated. The opposing second end 120 of the curved plate is inserted into die 510 and ram 520 presses down on the curved plate to form third radius of curvature 232 along third axis 230 between bottom ¼th and ⅓rd of rectangular portion 170 (
During each of the transverse bending steps described above, the down facing convex surface of plate 100 is supported by the concave up facing curved edges of endplates 705 and 710 of die 510. In one embodiment, the curvature of the concave upward facing edges of plates 705, 710 (512) is substantially the same as the curvature 212 of the plate 100, and is the same as the convex curvature of the ram. The effect of this is that the curvature 212 of the bend of the plate along the vertical axis is preserved while the first and second transverse bends are imparted to the plate.
The method further comprises coating the triple-curved armor plate 100 with spalling resistant polyurea elastomer based material. In certain embodiments, the polyurea elastomer coating is applied only to front surface 150. In certain embodiments, the polyurea elastomer coating is applied to both front surface 150 and rear surface 240. In certain embodiments, the polyurea elastomer coating comprises a thickness of about 0.25″ on the front surface 150.
In certain embodiments, the polyurea elastomer based coating is applied to the planer member before any of the bending steps. In further embodiments, the polyurea elastomer bases coating is applied after all the bending steps. In yet further embodiments, the polyurea elastomer based coating can be applied after the planar member is bent to form radius of curvature 212 along axis 210.
While the preferred embodiments of the present invention have been illustrated in detail, it should be apparent that modifications and adaptations to those embodiments may occur to one skilled in the art without departing from the scope of the present invention.
This application is a divisional of U.S. patent application Ser. No. 16/025,522, filed on Jul. 2, 2018, now U.S. patent Ser. No. 11,112,219, issuing Sep. 7, 2021, which is a divisional of U.S. patent application Ser. No. 15/013,906, filed on Feb. 2, 2016, now U.S. Pat. No. 10,030,942, issued on Jul. 24, 2018, which claims the benefit of and priority to U.S. Provisional Application No. 62/110,911, filed on Feb. 2, 2015, the disclosures of which are incorporated herein in their entirety.
Number | Date | Country | |
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62110911 | Feb 2015 | US |
Number | Date | Country | |
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Parent | 16025522 | Jul 2018 | US |
Child | 17467948 | US | |
Parent | 15013906 | Feb 2016 | US |
Child | 16025522 | US |