FIELD OF THE INVENTION
The present invention relates generally to ammunition. More particularly, the invention relates to an apparatus that can be used for training military personnel in firing projectiles.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-section along the length of a training round that incorporates one embodiment of a training projectile of the instant invention.
FIG. 2 is a perspective view of one embodiment of an assembled training round.
FIG. 3 is an exploded perspective view of one embodiment of a training round.
FIG. 4 is an enlarged cross-sectional view of one embodiment of the projectile portion of a training projectile.
FIG. 5A is a bottom plan view of one embodiment of a detonation fuse.
FIG. 5B is a perspective view of one embodiment of a detonation fuse.
FIG. 6 is a cut-away perspective view of one embodiment of a projectile body.
FIGS. 7A and 7B show partial cross-sectional views of one embodiment of an O-give and projectile body, illustrating the closure mechanism of the instant invention absent the retaining member.
FIG. 8 is a top plan view of one embodiment of the closure-mechanism retaining member.
FIGS. 9A and 9B show partial cross-sectional views of one embodiment of an O-give and a portion of the projectile body, illustrating the closure mechanism of the instant invention with the retaining member.
FIG. 10A is a bottom plan view of one embodiment of a projectile body.
FIG. 10B is a top plan view of one embodiment of a bottom-end, retaining member.
FIG. 10C is a top plan view of one embodiment of a back plate.
FIGS. 11A and 11B show cross-sectional views of alternate embodiments of a training projectile.
FIGS. 12A and 12B show cross-sectional views of alternate embodiments of a training projectile.
FIGS. 13A, 13B, and 13C show two cross-sectional views and a bottom perspective view, respectively, of an alternate embodiment of the O-give.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
For the purpose of promoting an understanding of the present invention, references are made in the text hereof to embodiments of a gun-launched, training ammunition, only some of which are depicted in the drawings. It is nevertheless understood that no limitations to the scope of the invention are thereby intended. One of ordinary skill in the art will readily appreciate that modifications such as those involving the type or caliber of training round, geometry and shape of the training projectile, or type of detonation fuse, do not depart from the spirit and scope of the present invention. Some of these possible modifications are mentioned in the following description.
Moreover, the term “substantially” or “approximately” as used herein may be applied to modify any qualitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. For example, a projectile body as disclosed herein as having a substantially cylindrical shape might permissibly have a somewhat non-cylindrical shape within the scope of the invention if its capability of functioning as a projectile body is not materially altered.
In the embodiments depicted, like reference numerals refer to identical structural elements in the various drawings.
FIG. 1 is a cross-sectional view of one embodiment of a gun-launched, training round, generally designated by the numeral 10, which incorporates a training projectile in accordance with the present invention. As shown here, training round 10 is a 40-mm training round. One of ordinary skill in the art will readily appreciate that the invention disclosed herein can be incorporated into a variety of ammunition sizes; for example training rounds in the 20-mm to 40-mm range. However, one of ordinary skill in the art will readily appreciate that aspects of the present invention may be incorporated into larger and smaller projectiles, as well as HEDP projectiles.
As shown in FIG. 1, training round 10 includes a frangible, training projectile 11 and a cartridge case 18. Training projectile 11 is substantially cylindrical in shape about axis A and is adapted to be partially contained and secured within cartridge case 18. In the embodiment shown in FIG. 1, training projectile 11 has at least one outside circumferential groove 27 for securing training projectile 11 within cartridge case 18 by clamping, or otherwise deforming, cartridge case 18 into groove 27. In the embodiment shown, cartridge case 18 is substantially cylindrical in shape and is shown to include a base plug 20, low pressure chamber 26, at least one vent 28 connecting low-pressure chamber 26 to propelling charge 24, and a percussion primer 22 adapted to ignite propelling charge 24. When propelling charge 24 is ignited, hot gases from ignited propelling charge 24 flow into low-pressure chamber 26 via at least one vent 28 to expel training projectile 11 from cartridge case 18, launching training round 10.
Referring still to FIG. 1, training projectile 11 comprises projectile body 14 and O-give 4. Projectile body 14 is substantially cylindrical in shape and has lower base 72 with a first and second end. Projectile body 14 also has upper wall section 73. O-give 4 comprises conical portion 70 and end portion 71, in which the outer diameter of conical portion 70 is larger than the outer diameter of end portion 71. O-give 4 is adapted to be slidably engaged with projectile body 14 by inserting end portion 71 of O-give 4 within upper wall section 73 of projectile body 14. One of ordinary skill in the art will readily appreciate that cavity 25, formed when projectile body 14 and O-give 4 are slidably engaged, may contain a brightly colored trace powder (not shown) to permit visual observation of training projectile 11 upon impact. In the embodiment shown, O-give 4 is made of aluminum, but could also be made of a plastic or a powdered metal that provide the sufficient structural strength.
In the embodiment shown in FIG. 1, training projectile 11 further comprises detonation fuse 7, anti-creeping spring 5 adjacent to detonation fuse 7, and firing pin 13 affixed to O-give 4. Anti-creeping spring 5 is, in one embodiment, a silicon tube. In this embodiment, firing pin 13 is adapted to be secured to inner surface 34 of O-give 4. Specifically, in the embodiment shown in FIG. 1, firing pin 13 is threadably secured to inner surface 34 of O-give 4. In alternate embodiments, however, firing pin 13 could be welded or otherwise molded to inner surface 34 or otherwise secured by means well known in the art. Although not shown here, in another embodiment, firing pin 13 and O-give 4 could be molded as one integrated piece (see FIGS. 11A-11B) and that portion of this application describing these figures. Moreover, firing pin 13 is only one embodiment of a firing member. Alternate embodiments of the firing member will be provided infra.
Furthermore, anti-creeping spring 5 is only one embodiment of an anti-creeping mechanism. The anti-creeping mechanism is to keep detonation fuse 7 in place, i.e., from moving forward and engaging firing pin 13, prior to impact. However, anti-creeping spring 5 must be of a resilience such that on impact, detonation fuse 7 moves towards firing pin 13, as discussed in greater detail infra. Additional alternate anti-creeping mechanisms include a wound spiral spring and a water band. Additional anti-creeping mechanisms will be provided infra.
FIG. 2 depicts a perspective view of one embodiment of training round 10 when it is assembled. Training round 10 can be used with a rifled gun barrel (not shown). Therefore, at least one rotation band 30 is machined or molded to the periphery of projectile body 14. Although not shown here, in alternate embodiments, rotation band 30 is a separate piece that is welded or otherwise bonded to training projectile 11 (see FIGS. 11A, 11B, and 13A). In one specific alternate embodiment, rotation band 30 is swaged on to the outer surface of training projectile 11. Rotation band 30 can be made of copper, another soft metal, or another material such as a plastic with similar properties. Rotation band 30 has an outside diameter slightly greater than the outside diameter of the remainder of projectile body 14, and the same or substantially the same outside diameter as the outside diameter of conical portion 70 of O-give 4 (as seen in FIG. 1). In practice, one of ordinary skill in the art will readily appreciate that rotation band 30 engages the gun barrel rifling (not shown) and imparts a spin to training projectile 11 about axis A when training round 10 is launched.
FIG. 3 depicts an exploded perspective view of one embodiment of training round 10, comprising training projectile 11 and cartridge case 18. Training projectile 11, which comprises projectile body 14, O-give 4, anti-creeping spring 5 (not visible), and detonation fuse 7, is also shown to include first retaining member 16, first sealing member 19, back plate 40, second sealing member 41, and second retaining member 42. In this embodiment, first retaining member 16 is a metallic snap ring, first sealing member 19 is an O-ring, second sealing member 41 is an O-ring, and second retaining member 42 is a C-clip, each of which will be described in more detail infra.
Referring to FIGS. 1 and 3, lower base 72 of projectile body 14 is provided with a substantially planar top surface 35 and a bottom surface 36. Upper wall section 73 of projectile body 14 extends axially from top surface 35. End portion 71 of O-give 4 is provided with an outer diameter that is slightly smaller than the inner diameter of upper wall section 73 to allow end portion 71 of O-give 4 to be inserted into upper wall section 73 of projectile body 14 and provide a snug fit. As described in more detail below, to assemble training projectile 11, end portion 71 of O-give 4 is slidably engaged with projectile body 14 and fixedly secured thereto.
FIG. 4 is a more detailed cross-sectional view of one embodiment of training projectile 11. In the embodiment shown, projectile body 14 is made of one piece and is forged or machined from round bar stock. Specifically, projectile body 14 is machined from an aluminum alloy bar stock. However, projectile body 14 can also be made of another material that provides comparable structural support and is of a similar density to simulate the external ballistics of a live HEDP projectile and can be made by casting or of a powdered metal. As can be seen in FIGS. 3 and 4, the bottom end of lower base 72 of projectile body 14 is tapered to allow projectile body 14 to slidably engage cartridge case 18.
Referring again to FIG. 4, projectile body 14 is provided with an axial bore 31. Axial bore 31 is generally cylindrical in shape and extends upward from the bottom end of lower base 72. Disposed within axial bore 31 is powder capsule 8. In this embodiment, powder capsule 8 is made of a plastic material and contains explosive charge 12, such as gunpowder. Projectile body 14 is further comprised of axial passage 33 that connects with axial bore 31 and extends to top surface 35. Axial passage 33 is cylindrically shaped as well, but has a smaller diameter than axial bore 31. On impact, detonation fuse 7 moves forward toward O-give 4, compressing anti-creeping spring 5, and firing pin 13 creates a small charge. The charge created by firing pin 13 is transferred through axial passage 33, which then ignites explosive material 12 contained in powder capsule 8. Thus, powder capsule 8 must be such that it can contain explosive material 12 so that it does not get into detonation fuse 7, but allows the spark generated on impact to pass through powder capsule 8 to ignite explosive charge 12
As shown in FIG. 4, detonation fuse 7 is disposed vertically adjacent to top surface 35 of projectile body 14. Detonation fuse 7 is a safety mechanism well known in the art that prevents training projectile 11 from arming itself unless a specific velocity and rotational speed is achieved. For example, in the embodiment shown here, detonation fuse 7 is the M550 Escapement Assembly, a government-designed and manufactured detonation fuse. With respect to this model, detonation fuse 7 must be spinning approximately 12,000 rpm before firing pin 13 will align properly and allow training projectile 11 to arm. One of ordinary skill in the art will readily appreciate that many other detonation fuses are available that will perform substantially the same function as the model shown here and, therefore, that can be used to practice the following aspects of this invention.
FIG. 5A is a bottom plan view of one embodiment of detonation fuse 7. FIG. 5B is a cut-away perspective view of the same detonation fuse 7. As shown in FIGS. 5A and 5B, detonation fuse 7 is substantially cylindrical in shape and has a top surface 47 and a bottom surface 37. Referring to FIG. 5A, detonation fuse 7 is provided with copper rotor 60 on bottom surface 37.
FIG. 6 is a cut-away perspective view of projectile body 14. Top surface 35 of projectile body 14 is provided with recess 50. As shown here, recess 50 is substantially circular. One of ordinary skill in the art will readily appreciate that recess 50 is adapted to receive rotor 60 of detonation fuse 7 when detonation fuse 7 is mounted on top surface 35.
Top surface 35 of projectile body 14 is further provided with a forwardly extending boss 39. As shown in FIG. 6, boss 39 is annular, circumferentially surrounding axial passage 33. Referring back to FIGS. 5A and 5B, bottom surface 37 of detonation fuse 7 is further modified to comprise circular recess 38 at its center. Recess 38 of detonation fuse 7 is adapted to receive boss 39, which allows detonation fuse 7 to maintain its centered position. In other words, by engaging recess 38 with boss 39, detonation fuse 7 remains centered so that it will not be pinned up against inner surface 34 of O-give 4 even at high rotational speeds. In this way, detonation fuse 7 can uninterruptedly rotate and ramp up to 12,000 rpm and properly arm.
Referring again to FIG. 4, detonation fuse 7, in the embodiment shown, is mounted on top surface 35. Spring ring 6 and anti-creeping spring 5 are positioned within O-give 4. In the embodiment shown here, anti-creeping spring 5 is annular and is made from rubber tubing. In an alternate embodiment, a foam sponge is used instead of rubber tubing. Spring ring 6 is disposed between anti-creeping spring 5 and inner flange 65 formed on inner surface 34 of O-give 4. Spring ring 6, in one embodiment, is made of 302 stainless steel, but also could be made of aluminum, plastic, or any other material with characteristics similar to that of 302 stainless steel. The combination of anti-creeping spring 5 and spring ring 6 prevents detonation fuse 7 from moving forward prematurely, but also allows detonation fuse 7 to move forward on impact. O-give 4 is then slidably engaged with projectile body 14 and fixedly secured thereto via the closure mechanism described as follows. However, training projectile, 11 could also be constructed without spring ring 6 so long as inner flange 65 of O-give 4 is sufficient to hold anti-creeping spring in place.
FIGS. 7A-7B are partial cross-sectional views of one embodiment of O-give 4 and projectile body 14. As shown in FIG. 7A, end portion 71 of O-give 4 has a smaller outer diameter than conical portion 70. The smaller outer diameter of end portion 71 forms outer flange 46 and allows end portion 71 to be inserted into upper wall section 73 of projectile body 14. In the embodiment shown in FIG. 7A, end portion 71 of O-give 4 has tapered lip 48 at its open end, and upper wall section 73 of projectile body 14 has tapered lip 18 its open end. However, tapered lip 48 and tapered lip 18 are not necessary elements and are only one exemplary embodiment.
Referring still to FIG. 7A, the closure mechanism comprises first circumferential groove 15 formed around outer surface 66 of end portion 71. Although not shown here, the closure mechanism further comprises first retaining member 16. In this embodiment, the first retaining member is a snap ring with a substantially rectangular cross-section (See FIGS. 9A-9B). Therefore, first circumferential groove 15 of end portion 71 of O-give 4, adapted to receive first retaining member 16, has a substantially rectangular cross-section. The closure mechanism additionally includes second circumferential groove 17 formed around inner surface 69 of upper wall section 73 of projectile body 14. Similar to first circumferential groove 15, second circumferential groove 17 is also adapted to receive first retaining member 16 and, thus, in this embodiment, second circumferential groove 17 also has a substantially rectangular cross-section. Second circumferential groove 17 is positioned at a depth within upper wall section 73 such that when end portion 71 of O-give 4 is inserted into upper wall section 73, first circumferential groove 15 of O-give 4 aligns with second circumferential groove 17 of upper wall section 73. FIG. 7B illustrates O-give 4 and projectile body 14 slidably engaged absent the first retaining member. As can be seen in this FIG. 7A, when O-give 4 and projectile body 14 are slidably engaged, first circumferential groove 15 and second circumferential groove 17 align and form annular cavity 29 into which the first retaining member fits.
In an alternate embodiment, end portion 71 of O-give 4 and wall section 73 of projectile body 14 each are constructed with corresponding threading. The two are then threadedly engaged to one another to affect an alternate closure mechanism.
FIG. 8 is a top plan view of one embodiment of first retaining member 16. In this embodiment, first retaining member 16 is a snap ring made of an aluminum alloy. However, in alternate embodiments, many kinds of durable, compressible, resilient materials, such as 302 stainless steel, mile steel, a hard grade of aluminum with some spring qualities (e.g., spring tensile aluminum) would be operative and are considered within the scope of the invention. As shown here, first retaining member 16 has gap 51. Gap 51 allows first retaining member 16 to be radially compressed or expanded, resulting in a smaller or larger diameter, respectively. For example, in this embodiment, first retaining member 16 has a diameter of approximately 1⅜ inches and gap 51 is approximately 1/4 inch when first retaining member 16 is at rest. When first retaining member 16 is radially compressed, however, first retaining member 16 assumes a diameter of approximately 1¼ inches. That first retaining member 16 can be radially compressed or expanded permits it to be placed within first circumferential groove 15 or second circumferential groove 16 before assembly and allows it to expand or contract within first circumferential groove 15 or second circumferential groove 16 while the training projectile is being assembled.
Although specific dimensions for first retaining member 16 are disclosed hereinabove, one of ordinary skill in the art will readily appreciate that the diameter of first retaining member 16 and the size of gap 51 will vary depending on the diameter of the two objects being fixedly secured together. For example, the embodiment disclosed herein is a 40-mm training round. However, ammunition of different sizes (e.g., 20-mm, 54-mm, etc.) will have projectile bodies and O-gives with varying diameters. Therefore, the diameter of the snap ring and the size of the gap necessarily will vary.
FIGS. 9A and 9B show partial cross-sectional views of one embodiment of O-give 4 and a portion of projectile body 14 and illustrate the manner in which O-give 4 and projectile body 14 are fixedly secured via the closure mechanism of the present invention. FIG. 9A illustrates O-give 4 with first retaining member 16 in place, prior to inserting end portion 71 into upper wall section 73 of projectile body 14. As shown here, first retaining member 16 is a snap ring with a substantially rectangular cross-section. Snap rings having cross-sections that are square, ovular with a notch, triangular, trapezoidal, hexagonal, circular with a notch, or polygonal, however, would also be operative as long as first retaining member can be held in place and are considered within the scope of the invention as well.
In practice, first retaining member 16 is positioned within first circumferential groove 15 by slightly expanding gap 51 so that first retaining member 16 can fit over lip 48 of end portion 71. As can be seen in FIG. 9A, when first retaining member 16 is at rest within first circumferential groove 15, the outer diameter of first retaining member 16 extends beyond the outer diameter of end portion 71. However, when first retaining member 16 is radially compressed, first retaining member 16 is recessed below the outer diameter of end portion 71.
End portion 71 of O-give 4 then is inserted into upper wall section 73 of projectile body 14. As discussed supra, lip 18 of projectile body 14 is tapered, allowing upper wall section 73 to slide over first retaining member 16, thereby radially compressing first retaining member 16 within first circumferential groove 15. Referring now to FIG. 9B, end portion 71 is pushed into upper wall section 73 until first circumferential groove 15 is aligned with second circumferential groove 17. Once second circumferential groove 17 passes over first retaining member 16, first retaining member 16 expands radially into second circumferential groove 17. After first retaining member 16 expands into second circumferential groove 17, the rectangular edges forming gap 29 prevent the disengagement of projectile body 14 from O-give 4 and, thereby, fixedly securing projectile body 14 to O-give 4.
One of ordinary skill in the art will realize, however, that first retaining member 16 could also be first placed within second circumferential groove 17 and lip 48 of end portion 71 of O-give 4 be slid within upper wall section 73 of projectile body 14 and over first retaining member 16. The end result, retaining member 16 within gap 29 formed by first circumferential groove 15 and second circumferential groove 17, locking O-give 4 to projectile body 14, is still achieved.
In the embodiment shown in FIGS. 7A, 7B, 9A, and 9B, the closure mechanism further comprises third circumferential groove 45 formed around outer surface 66 of end portion 71 between the underside of outer flange 46 and first groove 15. As shown in FIG. 7A, third circumferential groove 45 is adapted to receive first sealing member 19 (see FIGS. 9A and 9B) and, thus, has a substantially semicylindrical cross-section. Referring further to FIGS. 9A and 9B, first sealing member 19 is an O-ring positioned within third circumferential groove 45 before joining O-give 4 and projectile body 14 to achieve an airtight and watertight seal. In alternate embodiments where an airtight or watertight seal is not required, however, it is not necessary to position first sealing member 19 within third circumferential groove 45 in order to fixedly secure O-give 4 to projectile body 14.
To complete assembly of training projectile 11, powder capsule 8 is loaded with explosive charge 12 from the bottom end of projectile body 14. FIG. 10A, a bottom plan view of one embodiment of projectile body 14, illustrates bottom surface 36 of projectile body 14. Referring to FIG. 4 and FIG. 10A, bottom surface 36 is provided with access to axial bore 31 and a circular recess 78 to receive back plate 40. FIG. 10C is a top plan view of one embodiment of back plate 40. In this embodiment, back plate 40 is made of aluminum. However, in alternate embodiments, back plate 40 can be made of other suitable materials, such as mile steel. To prevent training projectile 11 from producing shrapnel, back plate 40 is etched with petals 43 to create weak points. Upon impact, back plate 40 breaks along petals 43 rather than producing shrapnel.
Referring again to FIGS. 4 and 10A, circular recess 78 within bottom surface 36 of projectile body 14 is provided with annular groove 77, which is adapted to receive a second sealing member 41. In this embodiment, second sealing member 41 is an O-ring. Circular recess 78 also comprises fourth circumferential groove 79, which is formed around the inside wall of circular recess 78 of bottom surface 36 of projectile body 14 and is adapted to receive second retaining member 42 for securing back plate 40 to projectile body 14 (see below). Once powder capsule 8 is loaded and second sealing member 41 is positioned within groove 77, back plate 40 is placed within recess 78.
Finally, back plate 40 is removably secured to projectile body 14 with second retaining member 42. FIG. 10B is a top plan view of one embodiment of second retaining member 42. In this embodiment, second retaining member 42 is a C-clip made of 302 stainless steel, but can also be made of spring steel or another material with properties similar to that of 302 stainless steel. As shown in FIG. 10B, second retaining member 42 is interrupted so as not to form a complete circle. Accordingly, second retaining member 42 has gap 54. To removably secure back plate 40, a hand tool is used to compress second retaining member 42 and insert it into groove 79. The tool fits into retaining member holes 53, allowing the user to radially compress second rotating member 52 so that it can be inserted into groove 79. Once second retaining member 42 is inserted into groove 79, second retaining member 42 is released and will expand radially into groove 79.
In this embodiment, gap 54 is approximately 3/8 inches and second retaining member 42 has a diameter of approximately 1 1/32 inches. However, gap 54 allows second retaining member 42 to be compressed, resulting in a diameter of approximately 15/16 inches. Although specific dimensions for second retaining member 42 are disclosed hereinabove, one of ordinary skill in the art will readily appreciate that the diameter of second retaining member 42 and the size of gap 54 will vary depending on the size of circular recess 78. For example, ammunition of different sizes (e.g., 20-mm, 54-mm, etc.) may have a circular recess that is larger or smaller than the one illustrated in this embodiment. Therefore, the diameter of the second retaining member 42 and size of the gap necessarily may vary.
FIGS. 11A, 11B, 12A, and 12B illustrate alternate embodiments of training projectiles of the instant invention. FIGS. 11A and 11B illustrate cross-sectional views of training projectile 211, alternate embodiments wherein the projectile body is not one integrated piece, but is comprised of a separate projectile sleeve 218 and projectile insert 214. As shown in FIG. 11A, training projectile 211 is shown to include projectile sleeve 218 and O-give 204, together forming chamber 209. Chamber 209 contains projectile insert 214, anti-creeping spring 205, and detonation fuse 207, all contained within chamber 209. In this embodiment, because bottom surface 236 of projectile sleeve 218 is closed, there is no need for a back plate or retaining ring on bottom surface 236. Rather, to assemble training projectile 211, powder capsule 208 and explosive charge 212 are loaded into projectile insert 214. Projectile insert 214 is then positioned within projectile sleeve 218. The remainder of the assembly is the same as that disclosed above.
As in the embodiment shown in FIGS. 1-4, firing pin 213 and O-give 204 are constructed of one piece. Specifically, in the embodiment shown in FIG. 11A, firing pin 213 and O-give 204 are molded or machined as one integrated piece. In alternate embodiments, however, firing pin 213 could be adapted to be secured to inner surface 234 of O-give 204. For example firing pin 213 could be threadably secured, welded, or otherwise secured to O-give 204 (as can be seen in FIGS. 1 and 4).
Similar to the embodiment disclosed above, bottom surface 237 of detonation fuse 207 is provided with a substantially circular recess 238 disposed at its center. Likewise, top surface 235 of projectile insert 214 is provided with a forwardly extending boss 239. Boss 239 is an annular protrusion that circumferentially surrounds axial passage 233. Recess 238 concentrically corresponds to boss 239. When detonation fuse 207 is mounted on top surface 235, recess 238 receives boss 239 such that detonation fuse 207 will remain centered. FIG. 11B illustrates training projectile 211 wherein detonation fuse 207 does not have recess 238 and, likewise, projectile insert 214 does not have boss 239.
In FIGS. 11A and 11B, at least one rotation band 230 is welded on to the periphery of projectile sleeve 218. As disclosed above, rotation band 230 can be made of copper or other metal, or in some instances, plastic. Rotation band 230 is the same or substantially the same diameter as the outer diameter of the conical portion of O-give 204. One of ordinary skill in the art will readily appreciate that, in alternate embodiments, rotating band 230 is machined or forged to the periphery of projectile sleeve 218. The purpose of rotating band 230 is to aid in the rifling of training projectile 211, to prevent damage to the rifling of the barrel, and to prevent gas from escaping the barrel when training projectile 211 is fired
Similar to the embodiment described supra, O-give 204 is fixedly secured to projectile sleeve 218 via the closure mechanism of the instant invention. In this embodiment, the closure mechanism comprises first retaining member 216, first circumferential groove 215 on O-give 204, and second circumferential groove 217 on projectile sleeve 218. The closure mechanism works in the same manner as described above.
FIGS. 12A and 12B show a cross-sectional view of alternate embodiments of training projectiles 311 and 312 in which the O-give and firing pin are not one piece. In the embodiment shown in FIG. 12A, training projectile 311 is shown to include projectile body 314 (one piece) and O-give 304, together forming chamber 309. Rotating band 330 is machined or forged to the periphery of projectile body 314. As with the previous embodiments, O-give 304 is fixedly secured to projectile body 314 via a closure mechanism in the same manner as described above. As shown in FIG. 12A, the closure mechanism comprises first retaining member 316, first circumferential groove 315 on O-give 204, and second circumferential groove 317 on projectile body 314.
Contained within chamber 309 is anti-creeping spring 305 and detonation fuse 307. In this embodiment, however, chamber 309 also contains firing pin assembly 323. Firing pin assembly 323 comprises a firing plate 306 and a firing pin 313. Firing pin 313 is secured to firing plate 306 by means well known in the art. Detonation fuse 307 and firing plate 306 are separated by anti-creeping spring 305. In this embodiment, firing plate 306 is disposed adjacent to inner flange 365 of O-give 304 and is held in place by anti-creeping spring 305. Similar to the embodiments shown hereinabove, anti-creeping spring 305 is annular and is comprised of rubber tubing. As in the embodiment provided supra, upon impact, detonation fuse 307 moves forward and firing pin 313 creates the small charge.
FIG. 12B illustrates training projectile 312 wherein the projectile body is not one integrated piece, but is comprised of a separate projectile sleeve 318 and projectile insert 314 and employs firing pin assembly 323, as provided in FIG. 12A. Therefore, in this embodiment, O-give 304 is fixedly secured to projectile sleeve 318 via the closure mechanism in the same manner as described above.
FIGS. 13A, 13B, and 13C show an alternate embodiment of O-give 404. FIGS. 13A and 13B are cross-sectional views and FIG. 13C is a bottom perspective view of O-give 404. As with earlier embodiments provided supra, detonation fuse 407, firing pin 413, end portion 471, axial passage 433, sleeve 418, rotation band 430, explosive charge 412, and projectile insert 414 can all be appreciated in FIGS. 13A and 13B. However, O-give 404 is further comprised of break-away tabs 405 which act as an alternate embodiment of an anti-creeping mechanism. When not in use, break-away tabs 405 are strong enough to keep detonation fuse 407 in position, away from firing pin 413. However, break-away tabs 405 are fragile enough such that upon impact of training projectile 411, break-away tabs 405 fracture or bend, allowing detonation fuse 407 to move forward and engage firing pin 413, thus creating the explosion of training projectile 411. FIG. 13A shows an embodiment of O-give 404 with break-away tabs 405 and firing pin 413 formed as one piece with O-give 404. FIG. 13B shows an embodiment of O-give 404, also with break-away tabs 405, but with firing pin 413 molded to O-give 404, but firing pin 413 could also be threadably secured or glued to O-give 404
FIG. 13C shows a bottom perspective view of O-give 404 shown in FIG. 13B. As can be appreciated, there are six (6) break-away tabs 405. However, there could be 2, 3, 4, 5, 6, etc. break-away tabs 405 so long as there is adequate support so that detonation fuse 407 does not move forward and engage firing pin 413 prior to impact. One of ordinary skill in the art will realize that the more break-away tabs 405 there are, the weaker and more readily broken or bent each one needs to be to permit forward movement of detonation fuse 407 upon impact.
Moreover, in one embodiment, as shown in FIG. 13B, inner edges 415 of break-away tabs 405 are rounded. In this embodiment, the length of break-away tabs 405 is such that detonation fuse 407 is under a slight biasing stress and break-away tabs 405 are very slightly flexed. The rounded inner edges 415 facilitate, upon impact, break-away tabs 405 bending or breaking outwardly, or away from rounded inner edges 415. One of ordinary skill in the art will appreciate that the outer edges of that part of break-away tabs 405 in contact with detonation fuse 407 could also be rounded, which would cause break-away tabs 405 to break or bend inwardly.
In yet another alternate embodiment of the anti-creep mechanism, positioned similarly as break-away tabs 405 relative to O-give 404 and detonation fuse 407 of FIG. 13B, one generally annular ring disposed on O-give 404, rather than a series of break-away tabs, can be employed to maintain detonation fuse 407 in position until impact. The generally annular ring would then have to be weak enough, or contain weak points, such that the annular ring would break or bend on impact of the projectile.
As disclosed and illustrated herein, the closure mechanism of the present invention may be incorporated in a training projectile. However, the closure mechanism of the present invention may be used in a variety of applications beyond training projectiles and the embodiments shown in FIGS. 1-12B are illustrative of a single application only.
Although, for convenience, the present invention has been described hereinabove primarily with respect to specific embodiments, it will be apparent to those skilled in the art that many variations of this invention can be made without departing from the spirit of the invention as claimed. The descriptions presented in those embodiments are not intended to demonstrate all of the possible arrangements and modifications to the design. For those skilled in the art, changes will be apparent that will fall within the spirit and the scope of the present invention.
Patent Application
20050263029
