Abstract:
A multi-petal adapter that enables projectiles of different sizes to be used in a single dearmer. The adapter includes a plurality of petals that are secured, in a detachable way, to a base. The main function of the base is to secure the petals until the projectile is fired from the dearmer. Whereupon, the adapter will start petalling until the petals become detached from the base, so that the adapter imparts minimal or no energy or damage to the intended target. The adapter fully regulates the energy imparted to the various projectiles, by allowing propellant gases to bleed through channels that are formed between the petals. As a result, the present adapter fully supports a proper projectile launch and ensures its proper orientation toward the target.

Description:
GOVERNMENTAL INTEREST 
     The invention described herein may be manufactured and used by, or for the Government of the United States for governmental purposes without the payment of any royalties thereon. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates in general to the field of devices for disarming bombs and ordnance. In particular, the present invention relates to an adapter that enables projectiles of different sizes to be used in a single dearmer. 
     BACKGROUND OF THE INVENTION 
     One technique for rendering an explosive ordnance device safe is to de-arm that device by rendering its fuze mechanism inoperative. This can be accomplished by destroying or damaging that fuze mechanism so that its firing pin will not be able to contact the detonator device. In this manner, the detonator will not set off the warhead of the ordnance device. De-arming an explosive ordnance in this manner requires the propulsion of a fuze destroying device against the fuze, with enough power to sufficiently damage the fuze and render it inoperative. 
     This result is generally accomplished by firing a projectile (or a slug) from a dearmer aimed, for example, at the fuze of the target, with enough velocity to impact a portion of the fuze extending out over the ordnance case. This impact bends the whole fuze body rendering the firing pin movement impossible, or in some cases, actually decapitating a portion of the ordnance item. 
       FIGS. 1 ,  2 , and  3 , illustrate a conventional de-arming device (or dearmer)  10  that includes a tubular body  12 . A cartridge case  14  containing a propellant charge, and a projectile (or slug)  16  are housed within the body  12 . A breech  18  is secured to the aft end of the body  12 , in order to lock the cartridge case  14  in position. The propellant charge is set off by a primer and propels the projectile  16  out of the body  12  at a velocity characteristic of that propellant charge. 
     Currently available dearmers (de-armers or disrupters) are designed to be exclusively used with projectiles of predetermined sizes. As more clearly illustrated in  FIGS. 1 and 3 , the projectile  16  fits into a matching bore in the dearmer body  12 . This limitation poses a serious logistics concern to the soldiers in the field, in that they are currently forced to use several dearmers that are dimensioned for different projectiles. 
     What is therefore needed is an adapter that enables projectiles of different sizes to be used in a single dearmer. The adapter should allow the dearmer to impart the appropriate amount of energy to the various projectiles, in order to propel them along the properly orientation. Furthermore, the adapter should guide the projectile toward the target. However, the adapter itself should not impart significant energy or damage to the target. Prior to the advent of the present invention, the need for such an adapter has heretofore remained unsatisfied. 
     SUMMARY OF THE INVENTION 
     The present invention satisfies this need, and describes a multi-petal adapter for use in conjunction with a dearmer. The adapter enables projectiles of different sizes to be used in a single dearmer. The adapter includes a plurality of petals that are secured, in a detachable way, to a base. 
     The main function of the base is to secure the petals until the projectile is fired from the dearmer. Whereupon, the adapter will start petalling until the petals become detached from the base, so that the adapter imparts minimal or no energy or damage to the intended target. 
     The adapter fully regulates the energy imparted to the various projectiles, by allowing propellant gases to bleed through channels that are formed between the petals. As a result, the present adapter fully supports a proper projectile launch and ensures its proper orientation toward the target. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other features of the present invention and the manner of attaining them, will become apparent, and the invention itself will be best understood, by reference to the following description and the accompanying drawings, wherein: 
         FIG. 1  is an isometric, exploded view of a conventional dearmer; 
         FIG. 2  is a cross-sectional view of the conventional dearmer of  FIG. 1 ; 
         FIG. 3 , is an enlarged, cross-sectional view of the assembled conventional dearmer of  FIGS. 1 and 2 ; 
         FIG. 4  is an isometric, exploded view of a dearmer according to the present invention, showing an adapter for accommodating a smaller size projectile; 
         FIG. 5A  is an isometric view of the adapter of  FIG. 4 , which includes three petals; 
         FIG. 5B  is an enlarged, isometric view of a representative petal of  FIG. 5A ; 
         FIG. 6  is an enlarged, top view of the adapter of  FIG. 4 ; 
         FIG. 7  is an enlarged, cross-sectional, side view of the adapter of  FIG. 5 , taken along line A-A′; 
         FIG. 8  is a cross-sectional view of the conventional dearmer of  FIG. 7 ; 
         FIG. 9  is an enlarged, cross-sectional view of the assembled dearmer of  FIGS. 4 and 8 ; 
         FIG. 10  is a partly cut-away, isometric view of the dearmer of 
         FIGS. 4 ,  8 , and  9 , shown in position for firing toward a target; 
         FIG. 11  is a partly cut-away, isometric view of the dearmer of  FIG. 10  after firing, and illustrating the petalling of the adapter; and 
         FIG. 12  is a partly cut-away, isometric view of the dearmer of  FIG. 11  upon impact with the target, and illustrating the destruction of the adapter and the penetration of a projectile through the target. 
     
    
    
     Similar numerals refer to similar elements in the drawings. It should be understood that the sizes of the different components in the figures are not necessarily in exact proportion or to scale, and are shown for visual clarity and for the purpose of explanation. 
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     A dearmer  100  of the present invention and its methods of assembly and use will now be described with reference to  FIGS. 4 through 12 .  FIG. 4  shows the dearmer  100  as being generally comprised of a tubular body  120  that is open at both its forward end  125  and its aft end  124 . 
     In this particular example, which is shown for illustration purpose only, it is desired to use a projectile (or slug)  160  having a ⅜-inch outer diameter, in a larger size body  120  with a 1-inch inner diameter forward bore  125 . It is further desired to use a cartridge case  140  of a uniform caliber that can be used to propel projectiles  160  of different sizes, without compromising the efficiency of the dearmer  100 . 
     The cartridge case  140  is inserted into a rearward bore  840  inside the body  120 , through the aft end  124 , and is then threadably locked in position with a breech  180 . The projectile  160  is fitted into a multi-petal adapter  111 , and the projectile ( 160 )/adapter ( 111 ) assembly is then inserted into the body  120 , through the forward end  122 . 
     Considering now the adapter  111  in greater detail with respect to  FIGS. 5A through 7 ,  FIG. 5  illustrates the adapter  111  as being formed of a plurality of petals, wherefore the name “multi-petal adapter.” In this particular illustration, the adapter  111  comprises three identical petals  501 ,  502 ,  503 . It should however be understood that a different number of petals may be used, and that these petals may differ in shape, depending on the intended application. 
     The petals  501 ,  502 ,  503 , are secured at their aft ends to a base  555 . While in this particular example, the base  555  is shown as being cylindrically shaped, it should be clear that the dimensions and shape of the base  555  may vary. In the present illustration, the outer diameter of the base  555  is approximately 0.415 inch, and its height is approximately 0.125 inch. 
     The main function of the base  555  is to secure the three petals  501 ,  502 ,  503 , until the projectile  160  is fired from the dearmer  100  or until the projectile  160  impacts a target  900  ( FIG. 12 ). Upon firing, the adapter  111  will start petalling until at least some of (or all) the three petals  501 ,  502 ,  503  become detached from the base  555 , so that the adapter  111  imparts minimal or no energy (or effect) to the intended target  900  ( FIG. 12 ). 
     An important feature of the adapter  111  is to allow some propellant gases to bleed (or escape) through the adapter  111 , upon firing of the cartridge case  140 , in order to control the energy imparted onto the projectile  160  (via the adapter  111 ). To achieve this goal, the three petals  501 ,  502 ,  503  are separated by three axial gas escape channels  511 ,  512 ,  513 , so that the adjacent petals (e.g.,  501 ,  502 ) are separated by a channel (e.g.,  511 ). In the present illustration, the width of each channel is constant along its entire length and is approximately 0.125 inch. 
     Considering now an exemplary design of the representative petal  501 , in connection with  FIGS. 5A ,  5 B,  6  and  7 . The petal  501  includes a flat, arcuate front edge  562  having a width of approximately 0.0625 inch. The outer arc of the arcuate front edge  562  defines, in combination with the corresponding arcuate front edges of the other two petals  502 ,  503 , and the gas escape channels  511 ,  512 ,  513 , the outer diameter of the adapter  111 . In this respect, every two adjacent channels, e.g.,  501 ,  502 , form an angle of 120°, as represented by the central angle ACB ( FIG. 6 ). 
     The petal  501  further includes two generally similar, flat external sides  560  and  561  that extend from the arcuate front edge  562  to a flat bottom edge  570  ( FIGS. 5A ,  5 B). The external sides  560 ,  561 , along with the corresponding external sides of the other two petals  502 ,  503 , define the gas escape channels  511 ,  512 ,  513 . In this illustration, the length of each external side  560 ,  561 , is approximately 1.750 inches. 
     The arcuate front edge  562  extends internally, downwardly, toward the bottom edge  570 , into a flared flange  564  that is defined by two sides  574 ,  576 , and that terminates in an internal arcuate edge  572 . The angle of inclination, a, between the arcuate front edge  562  and each side  574 ,  576  is approximately 45°. 
     As further illustrated in  FIGS. 8 and 9 , the flared flange  564 , along with the corresponding flanges of the other two petals  502 ,  503 , define a generally conical funnel  888 . The funnel  888  assists in the petalling of the adapter  111 , as it will be explained later in more detail. 
     The internal arcuate edge  572  defines, in combination with the corresponding internal arcuate edges of the other two petals  502 ,  503 , and the gas escape channels  511 ,  512 ,  513 , the inner diameter of the adapter  111 . In this illustration, the inner diameter of the adapter  111  is approximately 0.375 inch, in order to accommodate the ⅜-inch outer diameter projectile  160 . 
     The two external sides  560 ,  561  and the flared flange  572  extend internally, into an arcuately shaped, bore section  568 . The bore section  568  along with the bore sections of the other two petals  502 ,  503 , form an inner chamber  800  ( FIG. 8 ) for receiving the projectile  160 . 
     In a preferred embodiment, the adapter  111  is made of heat and pressure resistant material, such as polymers. It should however be understood that other suitable material may alternatively be used. 
     The adapter  111  may be made as an integral unit, by machining or molding. With reference to  FIG. 7 , the representative petal  502  is shown to be integrally made with the base  555 , and forms a attachment section  700  therewith. This attachment section  700  provides a secure, but weakened connection between each petal and the base  555 , in order to ensure the petalling and thus the destruction of the adapter  111 , prior to the penetration of the projectile  160  through the target  900  ( FIG. 12 ). 
     The assembly of the adapter  111  within the dearmer  100  will now be described in connection with  FIGS. 8 and 9 . The dearmer  100  is assembled for use by inserting the projectile  160  within the bore  800  of the adapter  111 . The adapter  111  that houses the projectile  160 , is then inserted into a cavity (or bore)  850  that is formed in the forward end of the body  120 , so that the arcuate front edge  562  of the adapter  111 , is substantially flush with a forward tip  925  of the body  120 . 
     In this position, and as illustrated in  FIG. 9 , the adapter  111  does not extend to the rear end  927  of the cavity  850 , because the projectile  160  is smaller than a projectile for which the bore  800  was dimensioned (e.g., compared to the slug  16  which fills the entire cavity of the body  12  in  FIG. 3 ). 
     When the projectile ( 160 )/adapter ( 111 ) assembly is secured within the body  120 , the adapter  111  defines an internal energy release chamber  890  within the cavity  850 . One of the functions of the energy release chamber  890 , in combination with the channels  511 ,  512 ,  513 , is to reduce the pressure behind the adapter  111 , in order to further control the exit velocity of the adapter  111  and consequently that of the projectile  160 . 
     By manually reducing or expanding the volume of the energy release chamber  890 , the user is capable of regulating the amount of energy imparted to the projectile  160 . As an example, if the projectile  160  has much smaller dimensions than the projectile for which the bore  800  was dimensioned, the energy required to propel the projectile  160  would need to be minimized. The volume of the energy release chamber  890  is controlled by the seating position of the adapter  111  in the body  120 . As a result, the user has the option to either expand or reduce the volume of the energy release chamber  890  by changing the seating position of the adapter  111 . This provides a controllable degree of adjustment of the chamber volume which affects the exit velocity of the projectile ( 160 )/adapter ( 111 ) assembly. 
     The operation or use of the dearmer  100  of the present invention, will now be described with further reference to  FIGS. 10 ,  11 , and  12 .  FIG. 10  illustrates the dearmer  100  as being assembled and positioned for firing toward the target  900 . 
       FIG. 11  is an exemplary view of the dearmer  100   FIG. 10  after firing. The channels  511 ,  512 ,  513  allow a certain amount of propellant gases to bleed therethrough, in order to regulate the exit velocity of the projectile ( 160 )/adapter ( 111 ) assembly. 
       FIG. 11  further illustrates the petalling of the adapter  111 . As used herein, the term “petalling” refers to the spreading out radially, in flight, of the petals  501 ,  502 ,  503 . Petalling is initiated by the expulsion of the projectile ( 160 )/adapter ( 111 ) assembly, whereupon, the funnel  888  ( FIG. 9 ) 
     In a preferred embodiment, when the air contacts the funnel  888 , the petals  501 ,  502 ,  503  start to pivot outwardly, about the  700 , until the time of impact of the projectile  160  with the target  900 . It is possible that during flight, some or all the petals  501 ,  502 ,  503  become detached from the base  555 ; however, in the preferred embodiment, it the impact shock causes all the petals  501 ,  502 ,  503  that have not already broken away from the base  555  during flight, to separate therefrom at the attachment section  700 . 
       FIG. 12  shows the dearmer  100  at approximately the moment impact with the target  900 , and illustrating the destruction of the adapter  111  and the penetration of the projectile  160  through the target  900 . As a result, only the projectile  160  substantially penetrates or damages the target  900 . 
     In the present embodiment, the bore  850  of the body  120  is smooth, and the petals  501 ,  502 ,  503  are designed with corresponding smooth outer surfaces. It should however be clear that, in order to accommodate rifled bores, rifling grooves could be cut into the petals  501 ,  502 ,  503  of the adapter  111 . These grooves, when used in a rifled disruptor or dearmer  100 , will impart spin to the adapter  111  and slug  160  during flight. 
     Although the present safety dearmer  100  has been described in connection with one exemplary application, it should be clear that the dearmer  100  may have multiple commercial applications, including but not limited to law enforcement.