Patent Application
20200378736
Embodiments of the present invention relate to the technical field of explosives. More particularly, the embodiments of the present invention are directed to explosive breaching of concrete or masonry walls containing rebar meshes.
Explosive breaching is a technique utilized by military and first responders in order to gain access to a house, vehicle, compound, or other type of fortification. There are many types of breaching techniques and one benefit of conducting an explosive breach is that explosives deliver high amounts of kinetic energy ideal for use against hardened targets.
Tools utilized by personnel responsible for conducting explosive breaching operations can vary based on the material make-up of the fortification. Fortifications that do not require large amounts of high explosives may be considered to be soft targets. Some examples of these types of targets may include wood doors, sheetrock, light aluminum, or other assemblies constructed of materials that are generally low in density and easy to manipulate.
Continuing along the target spectrum, fortifications may also exist that are considered to be hardened targets. These targets may include fortifications that are constructed of heavy and dense materials such as metal or concrete. The pinnacle of the hardened target spectrum is a double-reinforced concrete wall that includes two rebar meshes.
The tools used for explosive breaching vary depending on the target spectrum. While soft targets may require a small amount of sheet explosives in order to push open a locked door, a hardened target may require explosive shape charges that may be used to cut and shear the target.
A linear shaped charge is one type of device that is used to defeat structural targets. These devices consist of a V-shaped lining surrounded with explosive. The explosive is then encased within a suitable material that serves to protect the explosive and to confine (tamp) it upon detonation. Once initiated, the detonation projects the lining to form a continuous, knife-like (planar) jet. The jet cuts material in its path, to a depth depending on a number of variables.
Therefore, there is a need to manufacture an explosive breaching system that may be used to gain access thru a double-reinforced concrete or masonry wall. The system should ensure that access is gained in a single explosive event to include the cutting of any internal rebar meshes. Additionally, the explosive breaching system should provide access thru the fortification such that personnel may immediately enter the fortification via a man-sized hole.
It is the objective of the present invention to utilize explosive linear shape charges in a hexagon type configuration in order to gain explosive access and cut rebar mesh embedded within a concrete or masonry wall. Such a configuration is scalable and depends on a number of factors that include, but are not limited to, the size of the linear shape charge and the geometric configuration of the charges.
It is a further objective of the present invention to initiate each of the linear shape charges by using detonation cord in combination such that it will ensure explosive continuity with the bulk explosive or a booster.
It is a further objective of the present invention to be configured such that it may fit into a single backpack or multiple backpacks and assembled in the field when required.
It is still a further the objective that the invention uses a combination of linear shape charges that detonate simultaneously.
The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
FIG.6B is a cross sectional view of the linear shape charge 2 with priming port 3 configured for use with a booster 38 in accordance with one embodiment of the present invention.
FIG.6C is another cross sectional view of the linear shape charge 2 with priming port 3 configured for use with a booster 38 in accordance with one embodiment of the present invention.
The present invention will now be described in detail with reference to the accompanying drawings, wherein the same reference numerals will be used to identify the same or similar elements throughout the several views. It should be noted that the drawings should be viewed in the direction of orientation of the reference numerals.
The explosive wall breaching system 1 is a system having subsystems which include at a series of linear shape charges 2, corresponding priming ports 3, support bracket assembly 4, at least two t-locking plates 36, and initiator connector 5.
The housing 8 of linear shape charge 2 is rectangular in configuration and has an internal and external wall. On top of housing 8 is top lid 6. Removal of top lid 6 provides the operator access to the interior of housing 8. A set of support bracket male connectors 7 are present on the front surface of the housing 8. Each set of support bracket male connectors 7 serve as the interface connection point between linear shape charge 2 and support bracket assembly 4. Also located on the primary surfaces of the housing 8 are a series of hook extrusions 14 used to support securing mechanisms 9.
To close the housing 8, top lid 6 is placed upon the top surface of the housing 8. Top lid 6 seals the interior void of housing 8. A system of securing mechanisms 9 holds top lid 6 securely in position. Bungee 12 type fasteners serve as the securing mechanisms 9 within the illustration provided. Here, one end of bungee 12 is placed around hook extrusion 14 located on the exterior face of housing 8. Bungee 12 is then placed between the extrusions of top lid securing bracket 10 and secured to a second hook extrusion 14 located on the opposing exterior face of housing 8.
Alternatively, threaded fastener 15 can be used as securing mechanism 9, as illustrated in
An additional feature located on the surface of top lid 6 is priming port 3. Priming port 3 is a conically shaped hollow body which serves as an interface between the bulk explosive located within linear shape charge 2 and the initiation system. In some cases priming port 3 has vertical threaded extrusion 13. However, priming port 3 can also be configured to be a more truncated conically shaped hollow body with a predominantly horizontal protrusion 43 instead of a vertically threaded extrusion 13.
Three primary methods of initiation typically exist and priming port 3 may be configured to support each method. The first method of initiation uses detonation cord 11 within priming port 3 as illustrated in
Referring to
Material composition of liner 21 may be altered in order to vary target performance. As an example, a low hazardous liner with less penetrating energy may consist of a copper foam metal mesh material infused with explosive. Similarly, liner 21 may consist of reactive powders compressed within a metal foam matrix for enhanced penetration capabilities. In addition, liner 21 alloy may simply be altered to tantalum, aluminum, or other material alloys to alter or enhance explosive performance.
In some cases the net explosive weight of the explosive wall breaching charge 1 can also be reduced without loss of penetration capability. This is accomplished by using a composite liner 21. For example, rather than being formed using only a single metal, the liner 21 can be formed with at least two metals, as shown in
The configuration in
A second method of initiation of the current invention can be seen in
A third method of initiation of the current invention can be seen in
The detonating cord 11 is locked into booster 38 by a loop made as its end outside of priming port 3. The loop is locked by an adhesive tape 39. This configuration ensures the explosive continuity between the initiation system and the bulk explosive located within linear shape charge 2 and meets US DOD explosive procedures.
The building block of explosive wall breaching system 1 is support bracket assembly 4 as shown in
When assembled as shown in
In order to maintain detonation cord 11 accessible to the operator, separation bar 28 is used to connect within separation bar support hole 29. Cylindrical separation bar 28 is readily inserted into separation support hole 29 for assembly and this optional configuration enables explosive wall breaching system 1 to maintain its ability to be collapsible for ease of transport. Separation bar 28 also serves to prevent detonation cord 11 from crossing over on itself. If this were to occur, one strand of detonation cord 11 may cause one of the linear shape charges 2 to fire before the others and thereby degrade the performance of the tool.
The last major components of the embodiment of support bracket assembly 4 depicted in
Alternatively, the initiator connector 5 can be configured with a double initiation point as shown in
The primary component of initiator connector 5 is detonation cord housing 35. Detonation cord housing 31 is a hollow cylindrical body that is utilized in order to initiate all six strands of detonation cord 11 simultaneously with a single blasting cap 32. One end of detonation cord housing 31 is closed and the other end is open to enable the operator the ability to hand pack bulk explosive into detonation cord housing void 35. On the open end of the tube, threads or other fasteners are used as a blasting cap retention top 34 or 40. This configuration allows blasting cap retention top 34 or 40 to fasten to detonation cord housing 31 and thereby provide an interface between a blasting cap 32 and the bulk explosive contained within detonation cord housing void 35. Finally, features may exist on the exterior of detonation cord housing 31 to assist with the connection of detonation cord 11 to the exterior surface of the body.
To secure a blasting cap 32 within blasting cap retention top 34 or 40, blasting cap retention nut 23 is used. Blasting cap retention nut 23 is internally threaded and mates to the external threads located on blasting cap retention top 34 or blasting cap retention top 40.
The configurations of the illustrated embodiments of explosive wall breaching system 1 are intended to fire a series of shape charges in order to create a high pressure wave front and an explosive jet to destroy a concrete or mason type wall. Such configurations are also ideal for cutting multiple layers of rebar that may be meshed within the concrete or mason wall.
Prior to deploying explosive wall breaching system 1, an operator must load explosive components and assemble the device. To begin this process, the operator begins this process by filling linear shape charge 2 with bulk explosives. To accomplish this, top lid 6 is separated from housing 8 of linear shape charge 2 thereby enabling the operator access to main charge void 20 within housing 8. Bulk explosive is then added to main charge void 20 by pressing it in small amounts firmly against liner 21. The process of adding bulk explosive to main charge void 20 is repeated until the entire main charge void 20 is filled. This occurs when the bulk explosive is flush with the top surface of housing 8.
Upon filling main charge void 20, the operator may move his attention to top lid 6. With top lid 6 removed and turned over, the operator is able to access priming well void 18 and bulk explosive void 19. Much like the filling of main charge void 20, small amounts of bulk explosive are also added to priming well void 18 and bulk explosive void 19. The operator repeats the process of tamping and pressing the bulk explosive into place. This process is complete when bulk explosive entirely fills each of the two voids.
Alternatively, after filling main charge void 20, removing and turning top lid 6 over to allow access to bulk explosive void 19 of priming port 3, the operator places booster 38 in the predominantly horizontal protrusion 43 of priming port 3. The operator next inserts detonation cord 11 through the central hole of booster 38 and makes a loop on the end of detonation cord 11 outside of priming port 3 on the outside surface of top lid 6. The operator then locks the loop with adhesive tape 39 and then fills explosive void 19 with bulk explosive as described above.
Now that top lid 6 and housing 8 are hand packed with bulk explosive, the two components may be mated together and fastened into place as shown in
Another option to secure top lid 6 to housing 8 is illustrated in
The linear shape charge 2 assembly is now prepared to be fitted with detonation cord 11 as shown in
A second configuration is also possible for the connection of detonation cord 11 to priming port 3. This method requires a non-electric blasting cap 25 that is crimped to the end of detonation cord 11 and is illustrated in
The final preparation of linear shape charge 2 is to attach double sided adhesive to housing 8. This is accomplished by first cutting a piece of double sided adhesive to the length of housing 8 and then attaching one side of the adhesive to the bottom exterior surface of housing 8. Prior to immediate use, the operator removes the film protecting the other face of the adhesive. The adhesive is then used to support the load of explosive wall breaching system 1.
The preparation procedures for linear shape charge 2 may then be repeated for each of the remaining linear shape charges 2 that are to be used within explosive wall breaching system 1.
Attention is now focused on preparing detonation cord housing 31. To begin, the operator removes blasting cap retention top 34 or 40 to access detonation cord housing void 35. Bulk explosive is then hand packed into detonation cord housing void 35 and filled to capacity. This occurs when the bulk explosive reaches the top surface of detonation cord housing void 35. Once filled, the operator may attach blasting cap retention top 34 or 40. To complete the assembly of detonation cord housing 31, each of the six strands of detonation cord 11 are attached to the exterior surface of detonation cord housing 31.
With detonation cord housing 31 and linear shape charges 2 assembled for use, the operator may then elect to put the components of explosive wall breaching system 1 within a backpack or carrying case. Final assembly may then be completed immediately prior to use. An example of the time to complete final assembly would be the arrival of a team at the final staging area prior to an assault.
Once reaching the final staging area the team may remove each of the main components of explosive wall breaching system 1 from a backpack or transport container for final assembly.
Final assembly begins with the construction of support bracket assembly 4. This is done by fastening one end of extension bar 26 to support bracket assembly 4 via an interlocking tongue and groove system. Once extension bar 26 is mounted to support bracket assembly 4, linear shape charges 2 may be inserted. To accomplish this, each of the support bracket female connectors 27 are aligned with support bracket male connectors 7 located on each of the linear shape charges 2. Once aligned, linear shape charges 2 are pushed downward and locked into position.
With each of the linear shape charges 2 in position within support bracket assembly 4, the operator may then insert t-locking plate 36. T-locking plate 36 connects to support bracket assembly 4 and each of the two plates are locked into position via a tongue and groove fastening system.
Separation bar 28 is then attached to support bracket assembly 4 by inserting separation bar 28 into separation support hole 29 and locked into position by twisting separation bar 28. Once locked into position, detonation cord housing 4 may be attached to separation bar 28. This is done by clipping initiator clip 37 around separation bar 28.
Finally, a blasting cap 32 with initiation train 33 may be inserted into blasting cap rentention top 34 or 40. Once inserted into blasting cap retention top 34 or 40, blasting cap rentention nut 23 is secured to blasting cap rention top 34 or 40 via blasting cap retention thread 24. This process is similar to the integration of non-electric blasting cap 25 conducted for priming port 3 as previously discussed and shown in
When final stage assembly is completed, the double sided adhesive tape previously attached to the bottom of housing 8 is then prepared for attaching to the target surface. Explosive wall breaching system 1 is then placed into position by leaning the device against the intended target with support pole 30 extended and each of the linear shape charges 2 flush to the target wall.
Upon placement, the operator activates the detonation sequence of explosive wall breaching system 1 utilizing initiation train 33. Upon activation of the firing sequence, initiation train 33 transmits a current to the bridge wire of blasting cap 32. Detonation of blasting cap 32 occurs and thereby initiates the bulk explosive located within the detonation cord housing 4. Explosive continuity between detonation cord housing 4 and each of the six strands of detonation cord 11 then occurs.
Connected to the six strands of detonation cord 11 are each of the priming wells 18 of the six linear shape charges 2. Simultaneous detonation of each of the linear shape charges 2 occurs due to each strand of detonation cord 11 having identical length. Upon initiation of each priming well 18, the subsequent detonation of the bulk explosive located within bulk explosive void 19 occurs and is followed by the detonation of the bulk explosive located within main charge void 20. The leading edge of the detonation wave then contacts liner 21 thereby initiating the formation of an explosive jet.
The hexagonal configuration of the linear shaped charges 2 of explosive wall breaching system 1 allows the user to obtain an efficient one-step explosive wall breaching charge capable of creating a soldier-sized entry hole through steel-reinforced concrete walls where the concrete and all of the reinforcing steel are removed in a single process. This increases operator safety by minimizing time-on-target as well as increasing efficiency of defeating hardened structural targets.
| Number | Date | Country | |
|---|---|---|---|
| 62823168 | Mar 2019 | US |
