WO2000071964A1

WO2000071964A1 - Mine clearing device

Info

Publication number: WO2000071964A1
Application number: PCT/US2000/013105
Authority: WO
Inventors: James M. Brown; Michael T. Brown; Stephen Manders
Original assignee: Brisant Technologies International Llc
Priority date: 1999-05-13
Filing date: 2000-05-12
Publication date: 2000-11-30
Also published as: CA2337237A1; EP1097350A1; AU7050200A

Abstract

A detonating device (10) includes a hollow ribbon (20) having an interior cavity (40) defined therein, the hollow ribbon (20) being deployable along a ribbon path by means of a harpoon (18) being operably coupled to the hollow ribbon (20) and being discharged from a deployment assembly (14), the hollow ribbon (20) being fillable with an explosive material when deployed along the deployment path. A method of generating an overpressure condition along a path is included having a number of steps, including deployment of a hollow ribbon (20) along the path.

Description

MINE CLEARING DEVICE Technical Field

The present invention relates to devices for destroying land mine weapons and other unexploded ordnance in and on th^<. ground. More particularly, the present invention relates to overpressure type mine clearing devices.

Background of the Invention

According to the United Nations, more than 100 million land mines are buried worldwide. Exploding land mines kill or maim 2,000 victims, almost invariably a civilian person, every month, says the International Committee of the Red Cross. At the current rate of detection and removal, clearing the world's land mines would take hundreds of years. There are roughly 10 million land mines buried in Cambodia alone. What is needed is a safe, reliable and cost efficient technology for removing land mines.

Land mines may be cleared either by detecting the land mine and then carefully removing it without detonation or by detonation in situ.

A main problem in the detection of landmines is false alarms. Conventional metal detectors cannot discriminate between tin cans, bullets, scrap metal or land mines - which may be encased in metal or plastic. Current research is being conducted in enhanced ways to detect land mines. One such means is called nuclear quadruple resonance. By probing the earth with radio frequency signals, NQR can generate a coherent signal unique to certain compounds - including explosives such as RDX and TNT, found in the vast majority of the world's land mines.

Another promising device is called the meandering winding magnetometer. This device is based on a technology called magnito-quasistatics, which in principle can detect the size, shape, and properties of metallic objects underground by measuring their magnetic fields. A related technology called electro-quasistatics is designed to discover plastic objects.

As indicated above, land mines may also be cleared by mechanical detonation in situ. Such a device is called the Aardvark that is an armor plated vehicle produced in Scotland that destroys or detonates buried mines by beating the ground with rotating metal flails. Other means of such detonation include tank type vehicles having a mine clearing and detonating blade affixed to the front of the vehicle. Other such devices include robotic devices that may be directed to advance through a minefield, detonating the mines in its proximity, One recent report has concluded that "in the meantime, a well trained dog and a few digging implements remain the best tools for clearing mines", a dangerous proposition at best. In view of this conclusion there is a need for low-tech, low-expense land mine detonators for speeding the removal of the millions of buried explosives presently in existence. The emphasis has to be on low-tech and low-expense. As indicated above, many of the most serious land mine situations exist in third world countries where there is the need but not the financial resources in which to conduct mine-clearing operations with high-tech, high-expense devices. In order to be widely used, any such land mine clearing device should be readily portable and usable by relatively unskilled personnel. It would be a greater advantage if such a device could be used in battlefield situations as well as in the relatively more simple non-hostile mine clearing operations.

Summary of the Invention

The sub-surface ordnance and mine-clearing device of the present invention substantially meets the aforementioned needs of the industry. It also is at once effective in detonating or destroying buried and surface land mines, and surface and sub-surface unexploded ordnance, and is low-tech and low-expense. Accordingly, the present invention is usable by non-governmental teams involved directly and indirectly with the humanitarian demining issues and operations. It is further usable by military teams involved in minefield reaching and demining efforts including areas that contain unexploded ordinance and booby traps. The mine clearing devices are affordable by third world countries that are at present doing mine-clearing work solely by hand using meager digging tools. The mine-clearing device of the present invention further shows utility for federal and state DNR agencies responsible for ice control, avalanche control and beaver dam removal. The mine-clearing device may also have applicability for commercial mining operations, and demolition for highway and railroad construction.

The mine-clearing device of the present invention incorporates a unique approach to the deployment of high-grade explosives for generating an overpressure capable of detonating or destroying buried land mines. The device is safe, inexpensive and reliable, and lightweight such that it may be readily portable by a single operator.

The present invention is a detonating device that includes a hollow ribbon having an interior cavity defined therein. The hollow ribbon is deployable along a ribbon path by means of a harpoon being operably coupled to the hollow ribbon and being discharged from a deployment assembly the hollow ribbon being fillable with an explosive material when deployed along the deployment path. The present invention is further a method of generating an overpressure condition along a path is included having a number of steps including deployment of a hollow ribbon along the path.

Brief Description of the Drawings

Fig. 1 is a side elevational view of the harpoon assembly of the mine-clearing device of the present invention;

Fig. 2 is a side elevational view of the deployment assembly of the mine-clearing device of the present invention;

Fig. 3 is a side elevational view of the fill assembly of the mine-clearing device of the present invention;

Fig. 4 is a side elevational view of the mine-clearing device of the present invention where the hollow ribbon is deployed from a receptacle; Fig. 5 is a side elevational view of the mine-clearing device of the present invention where the hollow ribbon is deployed by a crossbow;

Fig. 6 is a side elevational view of the mine-clearing device of the present invention where the hollow ribbon is deployed by a compressed fluid mortar-type device

Fig. 7 is a side elevational view of the mine-clearing device of the present invention where the hollow ribbon is deployed by a spring actuated mortar-type device; and

Fig. 8 is a side elevational view of the mine-clearing device of the present invention where the hollow ribbon is deployed by a line coupled to a dart.

Detailed Description of the Drawings The mine clearing device of the present invention is shown generally at 10 in the figures. The mine-clearing device 10 has four major components: harpoon assembly 12, hollow ribbon assembly 13, deployment assembly 14, and fill assembly 16.

The harpoon assembly 12 has two sub-components: harpoon 18 and quick connect 22.

The harpoon 18 of the mine-clearing device 10 includes a harpoon tube 24. The harpoon tube 24 has an end cap 26 such that the distal end of the harpoon tube 24 is fiuidly sealed.

The harpoon tube 24 is a relatively thin tube wall 28, A cavity 30 is defined within the tube wall 28 that is open at the proximal end of the tube 24. The physical characteristics of the harpoon assembly 12 are preferably that the length is approximately 20 to 30 inches. The specific length bears a relationship to the length of the ribbon 20 that can be compressed into folds and slid over the exterior surface of the harpoon tube 24. The mass of the harpoon tube 24 also bears a relationship to the mass of the ribbon 20 that may be deployed, since effectively the harpoon tube 24 tows the ribbon 20 into deployment. The harpoon tube 24 preferably has an outside diameter of approximately 1.75 inches. Again there is a relationship to the inside diameter of the ribbon 20 in that the ribbon 20 must be capable of being slid over the exterior diameter of the harpoon tube 24. The harpoon tube 24 is preferably tubular in shape and may be formed of standard PNC piping, of corrugated paper tubing, aluminum, or other suitable, preferable light-weight material.

The second sub-component of the harpoon assembly 12 is the quick-connect 22. The quick connect 22 has a tapered tubular body 46. A longitudinal aperture 48 is defined in the quick connect 22 by the inside diameter of the wall 50 of the tubular body 45. A portion of the aperture 48 defines a receiver 52 for slidingly supporting the harpoon 18 therein. A circumferential seal 54 is disposed at the end of the tubular body 46 opposite to the receiver 52.

The second component of the mine clearing device 10 is the ribbon assembly 13. The ribbon assembly 13 includes a hollow ribbon 20 having an elongate ribbon body 34. The ribbon body 34 is substantially fluid tight and is flexible such that a series of folds 36 maybe formed in the body 34 for disposition of the ribbon 20 on the exterior surface of the harpoon 18. The ribbon body 34 has a sealed distal end 38 and defines an interior cavity 40. The ribbon body 34 has a proximal open end 42. The open end 42 is preferably fixedly, sealing and engaged with the quick connect 22 by an end clamp 44. The ribbon 20 is preferably made of Semi-mono-permeable polymer, but other similar materials also may be used. The ribbon 20 preferably has about a 3" inside diameter and may be 25'- 100' in length. The mass of the ribbon 20 should be low in order to enhance the range of deployment. As depicted in Figs. 4-8, the hollow ribbon assembly may be deployed directly from a receptacle 21 where the ribbon 20 is flaked down for rapid removal by withdrawal of a distal end 45 coupled to the harpoon 18 or otherwise by exerting a withdrawing force on the distal end 45 of the ribbon 20 (see Fig. 8). In certain applications, it is more convenient to withdraw the ribbon 20 from the receptacle 21 than to emplace the hollow ribbon 20 on the harpoon 18 prior to deployment (see Figs. 4 and 5). The third component of the mine-clearing device 10 is the deployment assembly 14. While deployment of the harpoon 18 maybe by compressed fluid as is described below, it should be noted that the deployment of the harpoon assembly may also be accomplished with a crossbow 104 or a spring 106 in a spring-loaded cylinder (see Figs. 5 and 7). The deployment assembly 14 has two major sub-components: the pressure vessel 56 and the actuator assembly 58.

The pressure vessel 56 has a volume defined therein for storing a fluid under pressure. The pressure vessel 56 tapers to a neck 60. An air valve 62 is connected to the neck 60. A hose 64 that is in fluid (communication with an air compressor or an air tank containing compressed air may be in a convention manner to the air valve 62 for filling the pressure vessel 56 with compressed fluid. Satisfactory deployment of the harpoon is achieved with a pressure in the pressure vessel 56 of 50-175 psi. Such pressure is achievable with readily available air compressors marketed for home use. The neck 60 of the pressure vessel 56 is sealably coupled to the actuator assembly 58. The actuator assembly 58 is a tubular device having a longitudinal fluid passage defined therein. A valve 66 is disposed in the fluid passage and is shiftable between an open disposition and a closed disposition by manual actuation of the handle 68. When the valve 66 is in the closed disposition, the volume defined within the pressure vessel 56 is sealed. When the valve 66 is in the open disposition, the compressed fluid within the pressure vessel 66 is free to discharge through the fluid passage defined in the actuator assembly 58. The distal end of the actuator assembly 58 includes a quick connect 70 that is designed to connect with the quick connect 22 of the harpoon assembly 12.

The third component of the mine-clearing device 10 is the fill assembly 16. The fill assembly 16 includes an elongated tube 72. The tube 72 may be approximately 5 feet in length and have an outside diameter of approximately 6.5 inches. In a preferred embodiment, the tube 72 is formed of standard PVC piping. The elongated tube 72 has a first lid 74 disposed at the first end of the elongate tube 72. The first lid 74 may be threadedly engaged with the elongate or may be bonded thereto. The first lid 74 includes an actuator assembly 76 that is similar in construction to the actuator assembly 58. Accordingly, the actuator assembly 76 has a valve 78 and a quick-connect 80. The quick-connect 80 is designed to mate with the quick-connect 22 of the harpoon assembly 12.

The elongate tube 72 has a interior charge volume 90 defined therein. Preferably, a quantity of an explosive material 92 is disposed in the charge volume 90. The explosive material 92 substantially fills the charge volume 90 between the first lid 74 and a plunger 94.

The plunger 94 is preferably disposed approximate the second end of the elongate tube 72.

The plunger 94 may be formed of solid foam rubber and has an exterior margin that is substantially coextensive with the margin of the charge volume 90 that is defined by the interior surface of the elongate tube 72. The plunger 94 is translatable within the charge volume 90.

A second lid 96 is disposed at the second end of the elongate tube 72. The second lid

96 may be threadedly engaged with the elongate tube 72 or bonded thereto. An air valve 98 is fixedly coupled to the second lid 96 for admitting a fluid under pressure from an exterior source into the charge volume 90 thereon the plunger 94. A pressure of 50-150 psi exerted on the plunger 42 is sufficient to discharge the explosive material 92 from the fill assembly

16 into the ribbon 20.

In operation, the harpoon assembly 12 is inserted into/onto the deployment assembly

14 and coupled thereto by means of the quick connect 22 and the quick connect 70. The valve 68 is positioned in the closed disposition. An air hose 64 is coupled to the an valve 62 and the pressure vessel 56 is filled with compressed air. The mine-clearing device 10 is then in the charged condition awaiting deployment of the harpoon assembly 12.

An operator aims the harpoon assembly 12 toward an area in which land mine detonation is desired to define the ribbon path. The mine clearing device 10) is hand-held and may be cradled with one hand and arm and actuated with a second hand. Remotely shifting the valve 66 by means of the valve handle 68 from the closed disposition to the open disposition results in ejection/launch of the harpoon assembly 12 from the quick connect

22/deployment assembly by means of the compressed air acting on the harpoon 18. The harpoon assembly 12 shoots outward carrying with it the ribbon 20/pulley assembly and cord. The pulley assembly and trailing cord are now in position for pulling the ribbon assembly into place.

At this point, the quick connect 22 is disengaged from the deployment assembly 14 and engaged with the quick connect 80 of the fill assembly 16. An air hose 64 is coupled to the air valve 98 and compressed air admitted to the charge volume 90 generates a force acting on the plunger 94. The valve 78 is then opened, and the force acting on the plunger 94 pushes the plunger 94 rightward as depicted in Fig. 3 dispelling the explosive material 92 from the elongate tube 72 to fill the ribbon 20. When the ribbon 20 has been filled with the explosive material 92, the quick connect 22 is disconnected from the quick connect 80 and a suitable detonator is connected to ribbon 20 with the explosive material 92 disposed therein. Detonation of the elongate ribbon 20 results in a blast producing an overpressure of between 50 and 200 Kbar. Such pressure is sufficient to detonate Land mines disposed along the path of the ribbon 20.

Referring to Figs 6-8, the harpoon 18 (dart 18a) is deployed from a mortar-type device that is supported on a chassis 180. Preferably, the chassis 180 has a pair of ground- engaging wheels 182. The chassis may be towed manually or by mechanized means form the distal end 184. The embodiments of Figs 6 and 8 have a pressure vessel 56 disposed in the chassis , as depicted in phantom in Fig. 8. The deployment assembly 14 includes a tube 185 for deploying the projectile (harpoon 18 or dart 18a).

The embodiment of Fig. 7 depicts deployment of a dart 18a. The dart 18a preferably has a slender body 186 that may be made of steel or other suitable material that has substantial mass and is able to impact the soil at the terminus of deployment and bury itself in a holding engagement therewith. The dart 18a may have stabilizing fins 188. After impact with the soil, the fins 188 may be buried in the soil and act as barbs to prevent the ready withdrawal of the dart 18a from the soil. The distal end of the hollow ribbon 20 is coupled to a first end 190 of a line 192. The line 192 is passed through a loop on the dart 18a and a second end 96 of the line 192 is disposed in a coil. Upon ejection of the dart 18a, the line 192 is deployed with the dart 18a, the dart 18a acting to uncoil the coils 198, 200. Once the dart 18a is embedded in the soil, the second end 196 of the line 192 may be hauled in, thereby simultaneously deploying the hollow ribbon 20 to as far as the embedded dart 18a. Once deployed, the line 192 may also be used to tow items other than the hollow ribbon 20 to the dart 18a. It will be obvious to those skilled in the art that other embodiments in addition to the ones described herein are indicated to be within the scope and breadth of the present application. Accordingly, the applicant intends to be limited only by the claims appended hereto.

Claims

1. A detonating device, comprising a hollow ribbon having an interior cavity defined therein, the ribbon being deployable along a ribbon path by means of a harpoon being operably coupled to the hollow ribbon and being discharged from a deployment assembly, the ribbon being fillable with an explosive material when deployed along the deployment path.

2. The detonating device of claim 1 wherein the ribbon is disposed in a compressed, folded state on the harpoon prior to deployment of the ribbon.

3. The detonating device of claim 2 wherein the harpoon is ejectable by an expanding fluid discharge, the ribbon having a first sealed end, the harpoon bearing on first sealed end and carrying the ribbon along the ribbon path when ejected by the expanding fluid discharge.

4. The detonating device of claim 3 wherein the harpoon is an elongate tube having a sealed first end.

5. The detonating device of claim 4 wherein the deployment assembly is capable of being hand-held.

6. The detonating device of claim 4 wherein deployment assembly is a mortar-like device.

7. The detonating device of claim 2 wherein the ribbon has sealed first end and an open second end, the open second end being selectively in fluid communication with the deployment assembly.

8. The detonating device of claim 7 wherein the harpoon bears on the ribbon sealed first end.

9. The detonating device of claim 8 wherein the harpoon is selectively in fluid communication with the hand-held deployment assembly, the expanding fluid discharged from the hand-held deployment assembly acting to propel the harpoon along a desired ribbon path, the propelled harpoon acting to deploy the ribbon along the desired ribbon path.

10. A method of generating an overpressure condition along a path, comprising the steps of: providing a projectile having a hollow ribbon operably detachably coupled thereto; discharging the projectile from a deployment assembly along a selected deployment path; deploying the ribbon along the selected ribbon deployment path ; filling the ribbon interior cavity with an explosive material when the ribbon is deployed along the deployment path; and detonating the explosive material.