Patent Grant
9303966
The invention relates generally to control of the shock-to-detonation transition process within a fuze explosive detonation train. More particularly, the invention relates to a flanged bobbin apparatus used to provide controlled distribution of the detonation transfer to the fuze booster and subsequently to the main explosive charge of a warhead when the lead detonation is initiated from an offset orientation.
Many existing general purpose bombs are designed to be detonated by a fuze initiation system that contains an explosive detonation train that typically contains a detonator and detonator lead that are located off-center (or offset) with respect to a hollow cylinder fuze booster charge in order to accommodate electrical cabling conduit that passes through the fuze booster. When used in combination with easily-detonated secondary main charge explosive fills, the offset initiation system of the explosive train is not typically a problem. However, more and more existing bomb and warhead designs are transitioning to insensitive main charge explosive fills in order to make the munition less responsive to unintended stimuli. Unfortunately, the complex geometry and multi-transient asymmetries created by an offset detonator system (as it will be referred to hereinafter) using an off center detonator lead complicates the shock-to-detonation transition process within the explosive detonation train, and impedes optimal detonation transfer to the main charge explosive fill. Furthermore, the offset detonator system leads to uncooperative detonation spreading behaviors, corner turning deficiencies, or other propagation problems that affect initiation and explosive performance in the main fill thereby rendering the explosive train ineffective for use with warheads filled with an insensitive explosive.
Accordingly, it is an object of the present invention to provide a shock-to-detonation transition distribution device for use in explosive trains with offset detonation leads.
Another object of the present invention is to provide an initiation distributor that works in perfect concert with the rest of the explosive detonation train to propagate a reliable detonation to an insensitive main explosive charge of a warhead.
Other objects and advantages of the present invention will become more obvious hereinafter in the specification and drawings.
In accordance with the present invention, an initiation distributor includes a first plate having a central hole and a plurality of first detonation transfer holes. The first detonation transfer holes are distributed about the first plate's central hole. The first plate has a first face with a depression well and channels defined therein that lead from the depression well to the first detonation transfer holes. The first plate also has a detonation transfer port located in line with one of the channels in the first plate. A second plate has a central hole and a plurality of second detonation transfer holes. The second detonation transfer holes are distributed about the second plate's central hole. The second plate has a detonation transfer port, and has a first face with channels defined therein that lead from the detonation transfer port in the second plate to the second detonation transfer holes. A coupler connects the central hole of the first plate to the central hole of the second plate, which may or may not be included in the present invention depending on manufacturing preference. In an exemplary embodiment, each of the first detonation transfer holes is aligned with a corresponding one of the second detonation transfer holes. Such alignment can be defined by the second detonation transfer holes being at mirror image locations with respect to the first detonation transfer holes, but the holes could also be indexed at a fixed angle relative to each other. A conduit couples the detonation transfer port in the first plate to the detonation port in the second plate. A resulting pathway is defined between the depression well and each of the first detonation transfer holes and each of the second detonation transfer holes. Continuous explosive material fills the depression well, the channels in the first plate, the first detonation transfer holes, the detonation transfer port in the first plate, the conduit, the detonation transfer port in the second plate, the channels in the second plate, and the second detonation transfer holes. A first covering is provided on the first face of the first plate, and a second covering is provided on the first face of the second plate.
Other objects, features and advantages of the present invention will become apparent upon reference to the following description of the exemplary embodiments and to the drawings, wherein corresponding reference characters indicate corresponding parts throughout the several views of the drawings and wherein:
Referring now to the drawings, simultaneous reference will be made to
Initiation distributor 10 includes end plates 12 and 14 coupled to one another by a central hollow spool or coupler 16. As is known in the art, coupler 16 defines an open-ended cylindrical region through which an electrical communication conduit (not shown or part of the present invention) passes for purpose of controlling bomb arming operations. Plate 12 is positioned adjacent detonation lead 100 and plate 14 is spaced-apart from plate 12 by coupler 16. Running parallel to coupler 16 and between plates 12/14 is a hollow and open-ended tube or conduit 18 whose function will be described later herein. The above-elements of distributor 10 are made from non-explosive material(s) and could be a monolithic structure or constructed as an assembly without departing from the scope of the present invention. Depending on the method of manufacture, coupler 16 may be eliminated or replaced by spokes, or the like, to position, mechanically, the plates 12/14 relative to each other. Initiation distributor 10 also includes a non-explosive material protective cover or seal 20 covering an outward-facing face of plate 12, and a non-explosive material protective cover or seal 22 covering an outward-facing face of plate 14.
In general, plates 12/14 and conduit 18 define a number of detonation pathways between detonation lead 100 and a donut-shaped booster charge material (not shown) that will be disposed between plates 12/14. Plates 12/14 may be circular and equal in diameter as shown, but this configuration is not a requirement of the present invention. Referring now to
Referring now to
For the axisymmetric detonation configuration of initiation distributor 10, approximately equal-length pathways should be defined between depression well 122 and each of detonation transfer holes 124 and each of detonation transfer holes 144. To do this, channel regions 145 must be configured to account for the length of conduit 18 which carries the explosive initiation train from plate 12 to plate 14 relative to the length of channel regions 125.
The advantages of the present invention are numerous. The initiation distributor is a simple apparatus that defines multiple point initiation pathways from an offset detonator system to both sides of a booster change. Upon firing, the detonation energy from the initiation distributor 10 propagates from each flange plate inner surface towards the center of the booster charge, where the detonation waves collide creating an implosion for a greater energy release rate. Thus, an exemplary embodiment of the present invention is readily adapted to satisfy shock-to-detonation transfer challenges posed by today's insensitive munition main charge explosive fill requirements. Detonation transfer hole placements, pathway lengths, and plate sizes may be adjusted to provide axisymmetric detonation conditions (as in the illustrated embodiment), or other specific detonation wave shaping schemes (e.g., asymmetrical, time-delayed, directionally-controlled waves, etc.) depending on the requirements of the application.
Although the invention has been described relative to a specific embodiment thereof, there are numerous variations and modifications that will be readily apparent to those skilled in the art in light of the above teachings. For example, detonation transfer holes in plates 12 and 14 may be positioned at non-mirror-image locations to enhance or otherwise alter the detonation wave interaction between the two plates. Another option is to have one detonation path length defined for plate 12 and a different detonation path length defined for plate 14 to thereby provide a delay in the detonation at one plate relative to the other plate. The detonation transfer holes may be located anywhere on the plates without departing from the scope of the present invention. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described.
Finally, any numerical parameters set forth in the specification and attached claims are approximations (for example, by using the term “about”) 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 be at least construed in light of the number of significant digits and by applying ordinary rounding.
The invention described herein was made in the performance of official duties by employees of the Department of the Navy and may be manufactured, used, licensed by or for the Government for any governmental purpose without payment of any royalties thereon.
| Number | Name | Date | Kind |
|---|---|---|---|
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| 3430563 | Stresau | Mar 1969 | A |
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| 3896731 | Kilmer | Jul 1975 | A |
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| 4145972 | Menz et al. | Mar 1979 | A |
| 4282814 | Menz et al. | Aug 1981 | A |
| 4475461 | Durrell | Oct 1984 | A |
