Door breaching device with safety adapter

Information

  • Patent Grant
  • 6408765
  • Patent Number
    6,408,765
  • Date Filed
    Tuesday, March 2, 1999
    25 years ago
  • Date Issued
    Tuesday, June 25, 2002
    22 years ago
Abstract
A breaching device for controlled blasting of an object at short range includes a blasting element including an explosive charge contained within a housing, the blasting element being configured to blast the object from a preset distance. Connected to, and extending from, the housing is a stand-off rod having a length equal to the preset distance. A pyrotechnic lead pellet is associated with the blasting element and with the stand-off rod so as to detonate the explosive charge upon impact of the stand-off rod with the object. A tail is provided for stabilizing the device during its flight to the object. The tail is connected to the blasting element through a “safe and arm” device and a safety connector configured to reduce shock forces acting on the tail resulting from detonation of the explosive charge.
Description




FIELD AND BACKGROUND OF THE INVENTION




The present invention relates to devices for quickly removing a door and, more particularly, to devices for breaching a door so as to permit access through the doorway.




In various applications, both civilian and military, it is often desired to quickly remove a door so as to gain access to a certain doorway which would otherwise be blocked by the presence of a locked door. For example, drug enforcement personnel frequently need to gain rapid entry into a dwelling during a drug raid. The entry must be effected quickly in order to prevent the occupants from hiding or destroying the drugs, from escaping the premises or from seizing arms and violently resisting the efforts of the authorities. Similarly, in various circumstances, police and/or military forces must be able to gain quick access to a house or other structure protected by a door, typically locked, in order to seize, preferably alive, one or more wanted persons inside the premises and/or to free innocent hostages held inside the structure. In all these cases access must be gained in such a way that neither the persons attempting to gain access nor the persons located in the structure beyond the door to be removed are injured.




Israel Patent No. 106629 teaches a door breaching system intended for such applications which will now be described in some detail. The system includes a device, illustrated in cross section in

FIG. 1

, which has a stabilizer body


10


for stabilizing the device during its flight to the proper location, namely, into contact with the object, typically a door, to be removed. Stabilizer body


10


typically includes a tail or wings to aid in aerodynamically stabilizing the launched projectile. Stabilizer body


10


may be of any suitable type including, but not limited to, any of a wide variety of suitable conventional or known stabilizer bodies which can be used in conjunction with various launched grenades, mortars, and the like. The illustrative stabilizer body


10


depicted in

FIG. 1

is similar to that commonly used to stabilizer anti-tank projectiles on their path toward a target.




The device further includes a shaped explosive charge


12


, preferably including high explosive. Shaped explosive charge


12


is shaped to effectively breach the object, e.g., a door, without causing more than minimal damage to persons and property near and beyond the door, when explosive charge


12


is detonated at a preset distance from the door. Preferably, the anterior face of shaped explosive charge


12


is substantially spherical, but many other shapes may be effective, depending largely on the nature and dimensions of the object to be breached and on the distance from the object at which the explosion is to take place.




Shaped explosive charge


12


is located in a housing


14


designed to allow the force of the explosion to be directed anteriorly rather than posteriorly.




Housing


14


may be made of any suitable material, preferably, housing


14


is made of a suitable plastic so as to limit the formation of dangerous shrapnel and thereby minimize potential injuries to personnel on both sides of the door being blasted.




Connected to housing


14


, or integrally formed with it, is a stand-off rod


16


of suitable length. Preferably, housing


14


and stand-off rod


16


are two discrete items which are readily connected to each other. Such an arrangement makes it easier to transport the disassembled device with rods


16


, housings


14


containing shaped explosive charges


12


and stabilizer


10


housed separately for easy storage and rapid assembly. The connection of stand-off rod


16


to housing


14


, when present, may be of any suitable type, including, but not limited to, by screwing or snap-fitting rod


16


into housing


14


, and the like. Rod


16


may be made of any suitable material, including, but not limited to, plastic and metal.




The length of stand-off rod


16


and the type, amount and shape of shaped explosive charge


12


are selected to optimize the ability of the device to effectively remove the object, such as door, without injuring persons or other property in the vicinity.




Preferably, stand-off rod


16


has connected to its anterior end an impact disc


18


having an effective diameter larger than the effective diameter of standoff rod


16


. Impact disc


18


may be integrally formed with stand-off rod


16


. Preferably, impact disc


18


is disc-shaped. The presence of impact disc


18


is intended to enlarge the area of direct impact with the door so as to lower the pressure at the point of impact and thus reduce or eliminate the possibility of stand-off rod


16


penetrating the door, thereby reducing the effectiveness of the device and potentially injuring persons and damaging property located beyond the door.




Included in the device is a suitable detonating means for detonating shaped explosive charge


12


substantially upon impact of the anterior end of stand-off rod


18


with the object, e.g., the door.




The detonation can be effected in any of a number of ways, including, but not limited to, by transferring the impact from the stand off rod to a striker which initiates an initiator. The detonation is transferred to a lead pellet


20


which detonates explosive charge


12


.




Preferably, the device also includes a “safe-and-arm” device (SAD)


22


of suitable design which prevents accidental or premature detonation of the device, as is commonly used in various current applications. SAD


22


may, for example, be selected to arm shaped explosive charge


12


only after a pre-selected time period has elapsed after the device has commenced to be propelled toward its target or after the device has been propelled through a pre-selected distance. SAD


22


may, for example, operate by bringing into alignment initiator and lead pellet


20


and shaped explosive charge


12


only after a certain period of time after launching of the device. Use of SAD


22


prevents the accidental detonation of the device but typically requires that the device be fired from beyond a certain minimum distance.




To use the device the operator connects a stand-off rod


16


to housing


14


of shaped explosive charge


12


. The operator mounts stabilizer


10


onto a suitable launcher (not shown), such as a grenade launcher or suitable gun. Alternatively, stabilizer body


10


could be replaced by a self-propelling device (not shown), such as that used in RPG rockets. Preferably, however, the device is mounted onto a suitable launcher or gun which provides the propulsion required to deliver the explosive over the relatively short distance between the launcher and the objective. The operator aims at the optimal point on the object, such as a door, and fires the launcher, propelling the device toward its target.




Upon impact of the anterior end of stand-off rod


16


with the door, the initiator located in SAD


22


detonates pellet


20


(assuming SAD


22


was already armed) which, in turn, immediately sets off shaped explosive charge


12


. The created explosion pressure waves spread in a way which depends on the nature, shape and quantity of the explosive used and on the distance from the target at the moment of explosion, which is determined largely by the length of stand-off rod


16


.




The device of Israel Patent No. 106629 clearly has many advantages for rapid and relatively non-destructive knocking down of doors. However, given the short ranges over which it is typically used, the device poses a potential hazard to the device operator and other personnel in his proximity. Specifically, there is a risk that part or all of stabilizer body


10


may be propelled rearwards at high speed by the force of the explosion, thereby injuring personnel.




There is thus a need for, and it would be highly advantageous to have, a device generally similar to the device described above for quickly and effectively breaking down a locked door which will not pose a safety hazard to the operator and other personnel in his vicinity.




SUMMARY OF THE INVENTION




The present invention is a door breaching device which includes a safety adapter.




According to the teachings of the present invention there is provided, a breaching device for controlled blasting of an object at short range, the device comprising: (a) a blasting element including an explosive charge contained within a housing, the blasting element being configured to blast the object from a preset distance; (b) a stand-off rod connected to, and extending from, the housing, the stand-off rod having a length equal to the preset distance; (c) a pyrotechnic lead pellet associated with the blasting element and with the standoff rod so as to detonate the explosive charge substantially upon impact of the stand-off rod with the object; and (d) a tail for stabilizing the device during its flight to the object, wherein the tail is connected to the blasting element through a safety connector, the safety connector being configured to reduce shock forces acting on the tail resulting from detonation of the explosive charge.




According to a further feature of the present invention, the safety connector includes: (a) a male portion attached to, or integrally formed with, the tail, the male portion having a substantially conical outer surface; and (b) a female portion attached to, or integrally formed with, the blasting element for receiving the male portion.




According to a further feature of the present invention, the male portion is made from a first material and the female portion is made from a second material softer than the first material, preferably, a polymer material. The first material is preferably metallic.




According to a further feature of the present invention, the safety connector further includes a detonating cord extending through both the male portion and the female portion.




According to a further feature of the present invention, the detonating cord extends through a bore located axially within the male portion.




According to a further feature of the present invention, the tail and the blasting element are configured to be directly connectable, and the safety connector is implemented as an adapter configured to be interposed between the tail and the blasting element.




According to a further feature of the present invention, the tail includes a bullet trap and is configured to permit launching of the breaching device from a rifle.




There is also provided according to the teachings of the present invention, a safety connector for connecting a tail to a warhead and configured to minimize backfire of the tail on detonation of the warhead, the connector comprising: (a) a male portion attached to, or integrally formed with, the tail, the male portion having a substantially conical outer surface; and (b) a female portion attached to, or integrally formed with, the warhead for receiving the male portion.




According to a further feature of the present invention, the male portion and the female portion are implemented as a pre-formed adapter configured to be interposed between the tail and the warhead.




There is also provided according to the teachings of the present invention, a method for minimizing backfire of a tail connected to a warhead on detonation of the warhead, the method comprising interposing between the tail and the warhead a safety adapter configured to reduce shock forces acting on the tail resulting from detonation of the warhead.











BRIEF DESCRIPTION OF THE DRAWINGS




The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:





FIG. 1

is a cross-sectional view through a prior breaching device;





FIG. 2

is a cross-sectional view through a breaching device constructed and operative according to the teachings of the present invention including a safety connector;





FIG. 3

is an enlarged cross-sectional view of the safety connector of

FIG. 2

;





FIG. 4

is a cut-away isometric view of the safety connector of

FIG. 2

; and





FIG. 5

is a cross-sectional view of a bullet trap for use in the breaching device of FIG.


2


.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




The present invention is of a door breaching device which can effectively be used to remotely blow away doors with minimal or no damage to the operator or to persons and property near and beyond the door.




The principles and operation of a device according to the present invention may be better understood with reference to the drawings and the accompanying description.




Turning now to the drawings,

FIG. 2

shows a breaching device, generally designated


30


, constructed and operative according to the teachings of the present invention, for controlled blasting of an object at short range.




Generally speaking, breaching device


30


is similar to the device of Israel Patent No. 106629 described above. Thus, breaching device


30


includes a blasting element


31


including an explosive charge


32


contained within a housing


33


. Blasting element


31


is configured to breach the door or other object from a preset distance. Connected to, and extending from, housing


33


is a stand-off rod


34


having a length equal to the preset distance. Typically, standoff rod


34


is connected at its anterior end to an impact disc


35


which has an effective diameter larger than the effective diameter of stand-off rod


34


.




Preferably, the device includes a suitable SAD


40


which prevents accidental or premature detonation of the device, as is commonly used in various known applications. SAD


40


may, for example, be selected to arm shaped explosive charge


32


only after a pre-selected time period has elapsed after the device has commenced to be propelled toward its target or after the device has been propelled through a pre-selected distance.




A detonator located inside SAD


40


is associated with blasting element


31


and stand-off rod


34


so as to detonate explosive charge


32


substantially upon impact of stand-off rod


34


with the object. Housing


33


preferably contains a lead pellet


36


which transfers the detonation from SAD


40


to explosive charge


32


. A tail


42


stabilizes device


30


during its flight to the object.




It is a particular feature of the present invention that tail


42


is connected to blasting element


31


through a safety connector


44


configured to reduce shock forces acting on tail


42


resulting from detonation of explosive charge


32


. This serves to minimize the risk of tail


42


, or any part thereof, being propelled rearwards in a manner that could cause injury to the operator or other personnel in his vicinity.




Details of a preferred implementation of safety connector


44


are shown in

FIGS. 3 and 4

. In this case, safety connector


44


includes a male portion


46


attached to, or integrally formed with, tail


42


. Male portion


46


features a substantially conical outer surface


48


which deflects a major part of the rearward detonation pressure wave outwards so that it is ineffective at propelling tail


42


rearwards. The other part of the connection is provided by a female portion


50


attached to, or integrally formed with, blasting element


31


and configured for receiving male portion


46


. Connection between male portion


46


and female portion


50


is preferably through complementary threaded portions towards the outer periphery of conical outer surface


48


.




Preferably, male portion


46


is made from a material significantly harder than that used for female portion


50


. This ensures that the detonation pressure wave destroys female portion


50


while leaving conical outer surface


48


intact to deflect the blast. Preferred materials for male portion


46


include, but are not limited to, metallic materials (metals and metal alloys) and especially lightweight structural materials such as aluminum. Female portion


50


is preferably made from polymer materials such as various types of plastics.




Preferably, safety connector


44


includes a detonating cord


52


which transfers the detonation from the detonator to lead pellet


36


and then to explosive charge


32


. Detonating cord


52


preferably extends through both male portion


46


and female portion


50


. A preferred location for detonating cord


52


, as illustrated here, extends through a bore located axially within male portion


46


. The use of a detonating cord is preferred over alternatives such as booster charges since it avoids damage to male portion


46


which could disrupt conical outer surface


48


.




Finally with regard to safety connector


44


, it should be noted that the connector may be implemented integrally with one or both of SAD


40


and blasting element


31


. However, in a preferred implementation, safety connector


44


is implemented as a preformed adapter configured to be located between SAD


40


and blasting element


31


. In the case shown here, male portion


46


is formed with an internal threaded portion while female portion


50


is formed with a corresponding external threaded portion. This allows the adapter to be interposed between SAD and blasting element components configured for direct connection.




Turning now to

FIG. 5

, a further preferred feature of breaching device


30


is that it may be launched from a standard rifle. To this end, tail


42


preferably features a bullet trap


60


which serves to safely contain a live bullet fired from the rifle while transferring the bullet's momentum to breaching device


30


. In the preferred implementation shown here, bullet trap


60


includes a primary trap


62


and a number of steel disks


64


to halt the bullet, as well as a bullet diverter


66


as an additional safeguard against the bullet impinging directly upon the explosive charge


32


. A black powder charge


70


, or any other suitable gun powder or propellant, is positioned in front of trap


62


so as to be ignited by the hot muzzle gases from the rifle barrel, thereby enhancing propulsion of the device. The forward movement of components of bullet trap


60


deforms diaphragms


68


which initiates the SAD arming process.




It will be appreciated that the safety connector of the present invention is not limited to the specific application of the breaching device described above but may equally be used for connecting a SAD to a warhead in a range of other applications. The present invention also provides a corresponding method for minimizing backfire of a tail connected to a warhead on detonation of the warhead in a wide range of applications.




It will be appreciated that the above descriptions are intended only to serve as examples, and that many other embodiments are possible within the spirit and the scope of the present invention.



Claims
  • 1. A breaching device for controlled blasting of an object at short range, the device comprising:(a) a blasting element including an explosive charge contained within a housing, said blasting element being configured to blast the object from a preset distance; (b) a stand-off rod connected to, and extending from, said housing, said stand-off rod having a length equal to said preset distance; (c) a pyrotechnic lead pellet associated with said blasting element and with said stand-off rod so as to detonate said explosive charge substantially upon impact of said stand-off rod with the object; and (d) a tail for stabilizing the device during its flight to the object, wherein said tail is connected to said blasting element through a safety connector, said safety connector being configured to reduce shock forces acting on said tail resulting from detonation of said explosive charge.
  • 2. The breaching device of claim 1, wherein said safety connector includes:(a) a male portion attached to, or integrally formed with, said tail, said male portion having a substantially conical outer surface; and (b) a female portion attached to, or integrally formed with, said blasting element for receiving said male portion.
  • 3. The breaching device of claim 2, wherein said male portion is made from a first material and wherein said female portion is made from a second material softer than said first material.
  • 4. The breaching device of claim 3, wherein said second material is a polymer material.
  • 5. The breaching device of claim 4, wherein said first material is a metallic material.
  • 6. The breaching device of claim 2, wherein said safety connector further includes a detonating cord extending through both said male portion and said female portion.
  • 7. The breaching device of claim 6, wherein said detonating cord extends through a bore located axially within said male portion.
  • 8. The breaching device of claim 2, wherein said tail and said blasting element are configured to be directly connectable, and wherein said safety connector is implemented as an adapter configured to be interposed between said tail and said blasting element.
  • 9. The breaching device of claim 1, wherein said tail includes a bullet trap and is configured to permit launching of the breaching device from a rifle.
  • 10. A safety connector for connecting a tail to a warhead and configured to minimize backfire of the tail on detonation of the warhead, the connector comprising:(a) a male portion attached to, or integrally formed with, the tail, said male portion having a substantially conical outer surface; and (b) a female portion attached to, or integrally formed with, the warhead for receiving said male portion, wherein said male portion is made from a first material and wherein said female portion is made from a second material softer than said first material.
  • 11. The safety connector of claim 10, wherein said second material is a polymer material.
  • 12. The safety connector of claim 11, wherein said first material is a metallic material.
  • 13. The safety connector of claim 10, further comprising a detonating cord running through both said male portion and said female portion.
  • 14. The safety connector of claim 13, wherein said detonating cord extends through a bore located axially within said male portion.
  • 15. The safety connector of claim 10, wherein said male portion and said female portion are implemented as a preformed adapter configured to be interposed between the tail and the warhead.
  • 16. A method for minimizing backfire of a tail connected to a warhead on detonation of the warhead, the method comprising interposing between the tail and the warhead a safety adapter configured to reduce shock forces acting on the tail resulting from detonation of the warhead.
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