Patent Publication Number: US-9845229-B1

Title: Apparatus for remotely lifting a buried explosive device

Description:
STATEMENT OF GOVERNMENT INTEREST 
     The invention described herein may be manufactured and used by or for the Government of the United States of America for Governmental purposes without the payment of any royalties thereon or therefor. 
    
    
     FIELD OF THE INVENTION 
     The invention relates in general to explosive ordnance disposal, and in particular to the removal of explosive devices that are buried in the ground. 
     BACKGROUND OF THE INVENTION 
     Explosive ordnance disposal (EOD) personnel (operators) are often required to carry the necessary EOD tools on their person for a long distance. This requirement may arise because the EOD work area is not easily accessible to vehicles or because vehicles are not available or for other reasons. In any event, the EOD tools and equipment must be small in size (or easily disassembled into a small size) and small in weight to enable carriage by an EOD operator. 
     In the case of buried explosive threats, the EOD operator often removes the explosive threat from the ground before disarming or otherwise neutralizing the threat. The explosive threat may be manually removed from the ground. Manual excavation may be accomplished by digging around the explosive threat using an ice ax, pick, shovel, human hands, probe, etc. These methods have a high risk of injury or death to the OED personnel. Thus, a method of removing the explosive threat from the ground where the OED operator is remote from the explosive threat is desired. 
     Many devices are known for lifting objects remotely from the ground, but most of the known devices are large and heavy and are not man-portable by one person. There are some known, man-portable remote removal devices. These conventional remote removal devices include tripods that are erected over the buried explosive device. First, a portion of the explosive device is manually uncovered. A lanyard or other connector (for example, a connector from a Hook and Line (HAL) EOD kit) is fixed at one end to the explosive device. The other end of the connector is fixed to the hub of the tripod or fed through a pulley that is fixed to the hub of the tripod. A pull line is connected to the hub of the tripod or to the connector that feeds through the pulley. The pull line is remotely pulled by one or more OED operators to lift the explosive device from the ground. In the case of an explosive device weighing up to 400 pounds, the conventional devices mechanically fail and do not lift the explosive device out of the ground. 
     A need exists for an apparatus and method for remotely lifting explosive devices from the ground. 
     SUMMARY OF THE INVENTION 
     It is an aspect of the invention to provide an apparatus for lifting a buried explosive device. Advantageously, the L-channel members will nest together to save pack space. Another advantage of apparatus  10  is the ability to configure the various L-channel members in other configurations that are useful to EOD operators, for example, a stand-off stick or disrupter stand. 
     The invention will be better understood, and further objects, features, and advantages thereof will become more apparent from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings, which are not necessarily to scale, like or corresponding parts are denoted by like or corresponding reference numerals. 
         FIG. 1  is a perspective view of one exemplary embodiment of an apparatus for remotely lifting a buried explosive device. 
         FIG. 2  is a left side view of  FIG. 1 . 
         FIG. 3  is a rear view of  FIG. 1 . 
         FIG. 4  is a front view of  FIG. 1 . 
         FIG. 5  is another perspective view of the apparatus of  FIG. 1 . 
         FIG. 6  is an exploded view of the apparatus of  FIG. 1 . 
         FIG. 7  is a schematic of a buried explosive device. 
         FIG. 8  is a schematic side view of the apparatus of  FIG. 1  with a pull line and an explosive device connected to it. 
         FIG. 9  is a schematic side view of the apparatus of  FIG. 1  showing the explosive device lifted out of the ground. 
         FIG. 10  is a cross-sectional view of an exemplary L-channel member. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1-6 , an apparatus  10  for removing a buried explosive device  42  ( FIG. 7 ) includes a T-shaped base  12  having a flange member  14  and a web member  16 . The web member  16  has one (first) end  22  fixed at a right angle to the midpoint  44  of the flange member  14  to form the T-shaped base  12 . A vertical upright member  18  is fixed at one (first) end to the midpoint  44  of the flange member  14  and is normal to the plane of the T-shaped base  12 . The vertical upright member  18  has a second end  24  that is distal the T-shaped base  12 . A diagonal member  20  has a first end fixed to the second end  24  of the vertical upright member  18  and is fixed at its second end to a second end  26  of the web member  16  that is distal the flange member  14 . 
     In an exemplary embodiment, the vertical upright member  18  is at least twice the length of the web member  16 . Particularly, the vertical upright member  18  is about 2.3 times the length of the web member  16 . The flange member  14  may be about the same length as the web member  16 . The difference in length between the vertical upright member  18  and the web member  16  produces a mechanical advantage when lifting explosive device  42 . This configuration is so because apparatus  10  functions as a lever having the form of a truss. The fulcrum of the lever is the midpoint  44  of flange member  14 . 
     The flange member  14 , the web member  16 , the vertical upright member  18  and the diagonal member  20  are, for example, L-channel members made of carbon fiber. The vertical upright member  18  may be made of at least two sub-members  18   a ,  18   b  and the diagonal member  20  may be made of at least two sub-members  20   a ,  20   b . The sub-members  18   a ,  18   b  and  20   a ,  20   b  may be connected together with fasteners  32 , such as threaded bolts and nuts. Fasteners  32  may be inserted in openings in the sub-members. 
     Apparatus  10  may be strengthened with a first brace  28  that extends at an angle from the vertical upright member  18  to one side of the flange member  14 . In addition, a second brace  30  may extend at an angle from another side of the flange member  14  to the web member  16 . Brace  30  is in the plane of the T-shaped base  12 . The first brace  28  and second brace  30  are fixed to flange member  14  on opposite sides of vertical upright member  18 . Braces  28  and  30  may be fixed at their respective ends to the other members using, for example, fasteners  32 , such as bolts and nuts. Braces  28  and  30  are, for example, L-channel members made of carbon fiber. 
       FIG. 8  is a schematic side view of the apparatus  10  of  FIG. 1  with a pull line  34  and an explosive device  42  connected to it. Pull line  34  has one (first) end fixed at the intersection of the second end  24  of the vertical upright member  18  and the diagonal member  20 . Pull line  34  may be, for example, a pull line from an EOD Hook and Line (HAL) kit. Pull line  34  may include pulleys or other devices. The other (second) end  46  of pull line  34  is free and is located distal the vertical upright member  18 . The other (second) end also known as the free end of line  34  is remote from apparatus  10  so that personnel pulling on line  34  will not be injured in case the explosive device  42  detonates while it is being pulled from the ground. 
     A connector  36  is configured to connect the apparatus  10  to the buried explosive device  42 . Connector  36  may be, for example, a lanyard or a connector found in a HAL kit. Connector  36  is fixed at one (first) end to the intersection of the second end  26  of the web member  16  and the diagonal member  20 . The other (second) end of connector  36  is fixed to the buried explosive device  42 . The top of the buried explosive device  42  is uncovered, for example, by manual means, so that connector  36  may be fixed to explosive device  42 . 
     The explosive device  42  that is disposed below the adjacent ground level G is fixed to the connector  36 . As shown in  FIG. 9 , the pull force on pull line  34  causes the apparatus  10  to rotate (counterclockwise in  FIG. 9 ), thereby lifting the explosive device  42  up to ground level without mechanical failure of the apparatus  10 . Apparatus  10  functions as a lever having the form of a truss. In particular, apparatus  10  may lift an explosive device  42  having a weight up to about 400 pounds. Once explosive device  42  is out of the ground, the EOD operators may better evaluate how to disarm or otherwise render device  42  harmless. 
     The L-channel members include flange member  14 , web member  16 , vertical upright member  18 , diagonal member  20  and braces  28 ,  30 .  FIG. 10  is a cross-sectional view of an exemplary L-channel member  38 . Each L-channel member includes a pair of legs  40 ,  40  normal to each other. In one exemplary embodiment, the L-channel members all have the same thickness and cross-sectional area. The thickness t of each L-channel member may be in a range of about 0.085 inches to about 0.165 inches. More particularly, the thickness t is about 0.125 inches. In one embodiment, each leg is of the same width w. The width w may be in a range of about 1.0 inches to about 2.0 inches. More particularly, the width w of the equal width legs is about 1.5 inches. 
     A suitable example of carbon fiber L-channel has a tensile strength of 512 ksi and a tensile modulus of 33.4 Msi. Carbon fiber L-channel may be obtained from, for example, DragonPlate.com, Elbridge, N.Y., USA. The commercial off the shelf L-channel may be sold in 4 foot lengths. 
     Apparatus  10  is carried by the EOD operator, along with many other items. In one embodiment, apparatus  10  has a weight less than about 5 pounds. More particularly, apparatus  10  has a weight of no more than about 3 pounds. In one exemplary embodiment, the length of vertical upright member  18  is in the range of about 36-42 inches and the lengths of web member  16  and flange member  14  are in the range of about 16-21 inches. Because upright member  18  and diagonal member  20  may be made of sub-members  18   a ,  18   b  and  20   a ,  20   b , the disassembled lengths of upright member  18  and diagonal member  20  are about one-half their respective assembled lengths. In terms of U.S. military applications, the back-packable length of the L-channel members is no more than about 24-30 inches. Advantageously, the L-channel members will nest together to save pack space. 
     Another advantage of apparatus  10  is the ability to configure the various L-channel members in other configurations that are useful to EOD operators, for example, a stand-off stick or disrupter stand. In addition, when multiple EOD operators each carry an apparatus  10 , the L-channel members of the multiple apparatus may be combined to construct, for example, a ladder or a pedestrian bridge. 
     Any numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of significant digits and by applying ordinary rounding.