BOOTS FOR MINIMIZING INJURY FROM EXPLOSIVES
A boot for reducing injury from a close range explosion includes a sole unit, an upper, and a shin guard. The sole unit includes at least an outer sole, a shank sheet composite, a shank filler and an insole. At least the shank sheet composite includes a plurality of layers having a pyramid shape and is formed of a strong composite fiber. The upper is attached to the sole unit and is formed of a laminated canvas. The shin guard is connectable to the upper and protects an ankle and leg of a user. The shin guard is formed of a strong composite fiber.
This patent application claims priority to Thai Patent Application No. 0701005013, filed on Oct. 3, 2007, the entire content of which are hereby expressly incorporated by reference.
TECHNICAL FIELDThe present invention relates generally to the field of protective footwear. In particular, the present invention relates to Explosive Ordnance Disposal (EOD) footwear.
BACKGROUNDThere are a number of live explosives buried beneath the surface, especially in conflict areas such as war zones. During combat, soldiers typically wear combat boots designed to protect their feet from rugged terrain and environments. While combat boots have traditionally been made of hardened leather, newer fabrics have recently been incorporated into combat boots to increase ventilation and comfort. Although combat boots are effective for protecting the feet of the user from natural elements, they are not as effective for preventing injury to the feet and lower appendages of the user from explosives.
Explosive Ordnance Disposal (EOD) boots are designed to prevent or reduce injuries to the lower appendages of a person that may be in direct contact with an explosive, such as a M14 anti-personnel mine (plastic mine). EOD boots are designed specifically to counteract an explosive force acting against the bottom of a user's foot. While effective, conventional EOD boots are heavy and bulky, making them uncomfortable to walk around in and difficult to quickly maneuver around in when traversing steep or rough terrain.
SUMMARYIn one embodiment, the present invention is a boot for reducing injury from a close range explosion and includes a sole unit, an upper, and a shin guard. The sole unit includes at least an outer sole, a shank sheet composite, a shank filler and an insole. At least the shank sheet composite includes a plurality of layers having a pyramid shape and is formed of a strong composite fiber. The upper is attached to the sole unit and is formed of a laminated canvas. The shin guard is connectable to the upper and protects an ankle and leg of a user. The shin guard is formed of a strong composite fiber.
In another embodiment, the present invention is a boot for protecting a lower appendage of a user. The boot includes a shoe and a shin guard. The shoe includes an upper and a sole unit attached to the upper. The sole unit includes a plurality of layers angled along a longitudinal axis extending from the toe portion to the heel portion of the sole unit at between about 102 degrees and about 112 degrees. At least one of the layers is formed of a strong composite fiber. The shin guard is positionable adjacent the upper.
In yet another embodiment, the present invention is an explosion ordnance device boot. The boot includes a shoe and a shin guard attachable to the shoe. The shoe includes an upper, an insole, a shank sheet composite, a filler, and an outer sole. The insole is bonded to the upper. The shank sheet composite includes at least eight angled layers, a top surface, a bottom surface, and a cavity formed at the top surface. The filler is formed within the cavity of the shank sheet composite. The outer sole is connected to the bottom surface of the shank sheet composite.
While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
The upper 16 covers the top contour of the foot and is designed to cover the foot up to the ankle. When the EOD boot 10 (
The upper 16 and the sole unit 18 are attached to each other with a high enough bond strength that in the event of an explosion, the EOD boot 10 does not completely break apart. At the same time, the bond between the upper 16 and the sole unit 18 is designed such that parts of the sole unit 18 can absorb part of the explosion by tearing or splitting, while still protecting the foot. For example, the EOD boot 10 is capable of withstanding a blast pressure of about 60-65 bars/110 msec and preventing gases produced from the explosion from contacting the skin. In one embodiment, the upper 16 and the sole unit 18 are attached at a bond strength of at least about 3 kg/cm standard. In another embodiment, the upper 16 and the sole unit 18 are attached at a bond strength of less than about 6 kg/cm. The sole unit 18 may be bonded to the upper 16 by pressing and curing. Alternatively, the sole unit 18 may be bonded to the upper 16, for example, by an adhesive system that is a mixture of phenol formaldehyde and vinyl resins dissolved in polar solvents. The sole unit 18 may also be bonded to the upper 16 by bonding and sewing.
The sole unit 18 is formed of four primary layers: an insole 20 (
The shank sheet composite 24 works as a fireproof and explosive barrier and has a top surface 48, a bottom surface 50, a toe portion 52, a mid-portion 54 and a heel portion 56. As can be seen in
Each of the layers of the shank sheet composite 24 has a pyramid shape that is closed at both the toe and heel portions 52, 56. The pyramid shape forms an angle along a longitudinal axis LA of the shank sheet composite 24 which extends from the toe portion 52 to the heel portion 56. The angle formed by each of the layers creates a channel 58 (
As mentioned above, the cavity 60 is filled with the shank filler 22, which allows the explosion forces to be absorbed before reaching the insole 20 (
The shank sheet composite 24 is composed of strong composite polymer fabrics that are lightweight and molded as shoe soles containing physical and mechanical properties that diminish scattered explosive forces. The combination of the strong composite polymer fabric and the apex shape of the shank sheet composite 24 dissipate some of the energy that may have broken into the surface of the shank sheet composite 24 from the outer sole 26 in the event of an explosion. While each of the layers of the shank sheet composite 24 are formed of the same material, each layer can be formed having a different thickness or a different density or tensile strength. In one embodiment, the outer layers have a higher density and greater tensile strength than the inner layers. Each of the layers has a thickness, for example, of about 0.5 millimeters.
The strong composite polymer fabric has the physical and mechanical properties to reduce vector forces, distribute blasting powers and effectively prevent fragments. In one embodiment, the strong composite polymer fabric is substantially as strong as a standard Level II small arm bullet proof material. In one embodiment, the strong composite polymer fabric has an embrittlement transition temperature of about −46 degrees Celsius, a weight of between about 9 and about 10.7 kg/m2, a modulus of about 27.5 KPa and includes about 57% to about 60% fiber. In one embodiment, the strong composite polymer fabric is a para aramid synthetic fiber. An example of a suitable para-aramid synthetic fiber includes Kevlar, available from Dupont. Examples of suitable aramids include Nomex, available from Dupont, Wilmington, Del.; Teijinconex, available from Teijin, Japan; New Star, available from Yantai, China; and Kermel, available from Kermel, France.
The outer sole 26 includes multiple rails at the middle apex 72 of the bottom surface 64 to provide toe flex at the toe portion 66 of the outer sole 26. In one embodiment, the toe portion 66 has a thickness of about 4 millimeters in order to allow flexibility, while the heel portion 70 has a thickness of between about 1.8 inches and about 2.5 inches to provide stability and support to the user.
The treads 74 provide friction between the shoe 12 and the surface the user is traversing to help the user navigate through rough terrains without slipping.
A blast directed at the sole unit 18 is reduced very quickly by the outer sole 26 breaking into small pieces or fragments at the same time. By allowing the outer sole 26 to easily break into small pieces, energy is scattered from the sole unit 18. The high abrasion resistance properties of the outer sole 26 is capable of quickly distributing blast forces, toxic gases and heat away from the sole unit 18. In one embodiment, the outer sole 26 is made of rubbers or polymers such as polyurethane.
When the shoe 12 includes a sock liner 29, the sock liner 29 is also formed, cut, or molded having substantially the same outline as the other components of the sole unit 18. The sock liner 29 is positioned within the upper 16 and adhered to the insole 20 by an adhesive. For example, the sock liner 9 is attached to the insole 20 using a glue.
The total blast or scattering energy dispersion on the shank sheet composite 24 is equal to the amount of energy lost at the outer sole 26, or R1+R2+R3+R4+R5. R1 is equal to the energy lost at the outer sole 26 and is the amount of energy remaining after the leaks that caused the outer sole 26 to break or split apart. R2 is equal to the scattering energy dispersed on the shank sheet composite 24, or the amount of energy remaining after the force has passed through the outer sole 26 and the shank sheet composite 24. R3 is equal to the energy absorbed by the shank sheet composite 24. After the shank sheet composite 24 collapses, air bubbles break in the body mass of the outer sole 26 and some of the energy is lost in R3. The R3 force is not normal to the plane of the insole 20 breaking into R4, which is perpendicular to the insole 20. R4 is equal to the amount of energy absorbed by the insole 20. R5 is equal to the trauma energy (i.e., remaining energy impact on the foot), or the vector force that results from the force which was reduced to force encounter to the sock liner 29. The decreased force that actually impacts the foot of the user of the EOD boot 10 allows the user to be taken to medics in time to save the limb.
The shin guard 14 is designed as a separate component from the shoe 12 (
To secure and remove the shin guard 14 to and from the user's leg, the shin guard 14 is positionable in an open position and a closed position. A securing mechanism 86 is located at the first edge 82 and correspondingly at the second edge 84 of the shin guard 14 and maintains the shin guard 14 in the closed position, wrapped around the user's leg. The securing mechanism 86 is also located at the bottom portion 80 of the inner side 74 of the shin guard 14 and correspondingly at the upper 16 of the shoe 12 to secure the shin guard 14 to the shoe 12. The securing mechanism 86 may be any connection means known in the art. For example, the shin guard 14 may be maintained in the closed position and to the shoe 12 using a hook & loop mechanism, commercially available under the tradename VELCRO®. The shin guard 14 is formed of about 1 to about 2 layers of polyurethane fabrics. The polyurethane fabric is also optionally laminated with a strong composite fabric, such as para aramid. In one embodiment, the inner side 74 and the bottom portion 80 of the shin guard 14 are laminated with the strong composite fabric.
EXAMPLESThe present invention is more particularly described in the following examples that are intended as illustrations only, since numerous modifications and variations within the scope of the present invention will be apparent to those skilled in the art. Unless otherwise noted, all parts, percentages, and ratios reported in the following examples are on a weight basis, and all reagents used in the examples were obtained, or are available, from the chemical suppliers described below, or may be synthesized by conventional techniques.
Various studies were performed associated with boot engineering, physiology, anatomy, ergonomics and personal safety to develop a boot that reduces injuries from personnel explosives. Sample boots were tested in the field using simulated legs and M14 anti-personnel mines. The simulated legs represent the anatomy of a leg, ankle and foot with proper chemicals, nylon felts, gelatin and polymer materials according to the Aberdeen Ordnance Division, USA.
The EOD boot tested was formed at least in part of Kevlar. The M14 anti-personnel plastic mine was positioned at a toe portion, a mid portion and a heel portion of the EOD boot of the present invention and at a toe portion, a mid portion and a heel portion of a comparative combat boot. Each of the explosions were set off separately. Table 1 compares the condition of the EOD boot of the present invention and the condition of the combat boot after being directly exposed to each of the explosions.
As illustrated in Table 1, the EOD boot was able to withstand explosions at all three portions of the boot better than the comparative combat boot. While the combat boot was damaged after being exposed to explosions at the toe portion, the mid-portion and the heel portion of the EOD boot, the EOD boot remained substantially intact after being exposed to explosions at the same locations. In particular, the outer sole and the shank filler of the EOD boot broke into pieces to deflect some of the forces from the explosions. The eight layers of the shank sheet composite, or middle sole, peeled off and left about four layers under the foot. The insole remained completely intact. This indicated that while the bone of the foot might be cracked, it was not severed from the ankle or cut and could be treated as a single unit.
At locations proximate where the explosions took place, the EOD boot had a buckle, or dent. The mid-portion of the EOD boot had a higher degree of buckling because the surface area of the mid-portion was greater than the surface areas of either the toe portion or the heel portion. In addition, the simulated leg wearing the EOD boot exposed to the explosions only split a little bit and generally looked intact. On the other hand, the simulated leg wearing the comparative combat boot was damaged below the knee.
The results in Table 1 show the ability of the EOD boot to reduce injury to a user, i.e., the ability to protect a foot wearing the EOD boot and the area of the leg under the knee covered by the shin guard when exposed to a blast, heat or fragments. The foot and leg were not badly injured other than a few cuts and splits. This satisfies the main purpose of the EOD boot, which is to provide the user with enough protection to be able to send patients to be treated by a physician so that the physician can save the user's foot and/or leg.
The EOD boot reduces injury from personnel explosives and is used as part of personal safety equipment to reduce injuries to the leg and foot for bomb squads and for people living in dangerous areas. Conventional EOD boots were not constructed for comfortability. They were bulky, heavy, rigid and less flexible, possibly causing knees to twist while walking, especially when the EOD boot is worn for a long time period of time or worn while traversing rough, steep terrains.
Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present invention. For example, while the embodiments above refer to particular features, the scope of this invention also includes embodiments having different combinations of features and embodiments that do not include all of the features. Accordingly, the scope of the present invention is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof.
Claims
1. A boot for reducing injury from a close range explosion comprising:
- a sole unit including at least an outer sole, a shank sheet composite, a shank filler and an insole, wherein at least the shank sheet composite includes a plurality of layers having a pyramid shape and comprises a strong composite fiber;
- an upper attached to the sole unit, wherein the upper comprises a laminated canvas; and
- a shin guard connectable to the upper for protecting an ankle and leg of a user, wherein the shin guard comprises a strong composite fiber.
2. The boot of claim 1, wherein the strong composite fiber is fire retardant, reduces vector forces, distributes explosive powers and prevents fragments.
3. The boot of claim 1, wherein the strong composite fiber comprises para aramid synthetic fiber.
4. The boot of claim 1, wherein the upper is attached to the sole unit at a bond strength of at least about 3 kg/cm standard.
5. The boot of claim 1, wherein the pyramid shape of the shank sheet composite is angled at between about 102 degrees and about 112 degrees along a longitudinal axis extending between a toe portion and a heel portion of the shank sheet composite.
6. The boot of claim 1, wherein the sole unit and upper have a weight of between about 1 kilogram and about 1.5 kilogram.
7. The boot of claim 1, wherein the outer sole is designed to break apart upon contact with a force of at least about 60-65 bars/110 msec.
8. A boot for protecting a lower appendage of a user, the boot comprising:
- a shoe comprising:
- an upper; and
- a sole unit attached to the upper and including a toe portion, a heel portion and a plurality of layers, wherein at least one of the layers comprises a strong composite fiber; and
- a shin guard positionable adjacent the upper;
- wherein at least a portion of the sole unit is angled along a longitudinal axis extending from the toe portion to the heel portion of the sole unit at between about 102 degrees and about 112 degrees.
9. The boot of claim 8, wherein the strong composite fiber comprises para aramid synthetic fiber.
10. The boot of claim 8, wherein the upper and the sole unit are bonded at a bond strength of at least about 3 kg/cm standard.
11. The boot of claim 8, wherein the shin guard comprises a strong composite fiber.
12. The boot of claim 8, wherein the sole unit comprises:
- an insole;
- an outer sole;
- a shank sheet composite positioned between the insole and the outer sole; and
- a shank filler formed within a cavity of the shank sheet composite.
13. The boot of claim 8, wherein the outer sole is designed to break apart upon contact with a force of at least about 60-65 bars/110 msec.
14. An explosion ordnance device boot comprising:
- a shoe comprising:
- an upper;
- an insole attached to the upper;
- a shank sheet composite including at least eight angled layers bonded to the insole, wherein the shank sheet composite includes a top surface, a bottom surface, and a cavity formed at the top surface;
- a filler formed within the cavity of the shank sheet composite; and
- an outer sole connected to the bottom surface of the shank sheet composite; and
- a shin guard attachable to the shoe.
15. The boot of claim 14, wherein each of the angled layers of the shank sheet composite are angled along a longitudinal axis extending between a toe portion and a heel portion of the shank sheet composite at between about 102 degrees and about 112 degrees.
16. The boot of claim 14, wherein the shank sheet composite comprises a strong composite fiber.
17. The boot of claim 16, wherein the strong composite fiber comprises para aramid synthetic fiber.
18. The boot of claim 14, further comprising a sock liner engaging the insole.
19. The boot of claim 18, wherein the upper is bonded to the insole at a bond strength of at least about 3 kg/cm.
20. The boot of claim 19, wherein the outer sole comprises polyurethane.
Type: Application
Filed: Oct 3, 2008
Publication Date: Apr 9, 2009
Applicant: BANPAN RESEARCH LABORATORY CO. LTD. (Bangkok)
Inventors: Weera Phlawadana (Bangkok), Vicha Vanadurongwan (Bangkok)
Application Number: 12/245,346
International Classification: A43B 3/00 (20060101); A41D 17/00 (20060101); A43B 1/08 (20060101); A43B 23/00 (20060101); A43B 13/14 (20060101); A43B 23/07 (20060101); A43B 13/38 (20060101);