PROJECTILE WITH FIRE-SAFE INFRA-RED STRIKE POINT MARKING
A projectile (100, 100a, 100b, 100c) containing two chemiluminescent dye components (123, 125), a dye powder (126) and one or more capsules (170) containing a pyrophoric substance. Upon impact at a target, a nose cap (110) of the projectile (100, 100a, 100b, 100c) and the capsule(s) (170) become broken, thereby allowing the pyrophoric substance to oxidize and emit an infra-red signal to mark the strike point. Oxidation of the pyrophoric substance is controlled, to allow the projectile to be fire-safe.
The present invention relates to projectiles with infra-red strike point marking. In particular, these projectiles are useful for training purposes or for use as marker rounds.
Background
Practice ammunition has been in use. For example, U.S. Pat. No. 7,004,074, assigned to Martin Electronics, describes a practice projectile 10 containing a powder dye charge 14 (see
In another example, U.S. Pat. No. RE40,482, assigned to Nico-Pyrotechnik Hanns-Juergen, describes a practice projectile in which a marking agent is contained in a frangible hood at the head of the projectile. The marking agent consists of two chemical components contained in separate, adjacent compartments. These compartments share a common partition that has predetermined thin regions. When fired, the acceleration forces on the projectile break these thin wall regions to allow the two chemical components to react and give a chemo-luminescent light. The luminous light is emitted through the transparent hood while the projectile is in flight. Upon striking the target, the hood bursts to scatter the luminous chemical dye, thereby making the strike point optically visible. Due to use of the luminous dye, this projectile is limited to night-time use.
U.S. Pat. No. 7,475,638, also assigned to Nico-Pyrotechnik Hanns-Juergen, describes an improved projectile 50 that is usable for both day and night time use. In this projectile, two chemically active marking materials are separately contained in two containers 55, which are placed side-by-side to each (see
It is appreciated that larger quantities of projectiles are used in training than in service; as such, cost becomes a very important factor in providing training projectiles. Coupled with limitations of known projectiles, it can thus be seen that there exists a need to provide projectiles with infra-red strike point marking to meet current and future challenges.
SUMMARYThe following presents a simplified summary to provide a basic understanding of the present invention. This summary is not an extensive overview of the invention, and is not intended to identify key features of the invention. Rather, it is to present some of the inventive concepts of this invention in a generalized form as a prelude to the detailed description that is to follow.
The present invention seeks to provide a frangible projectile with strike point marking for training purposes or for use as marker rounds during both day and night. The chemiluminescent dye material contained in the projectile is activated after the projectile is launched and the flight time allows the chemiluminescent dye to produce an effective glow at the point of impact. In addition, the pyrophoric substance is released at the point of impact to emit an infra-red signal.
In one embodiment, the present invention provides a projectile that emits an IR signal so that it is useful for night-time use. Another advantage is the projectile being fire-safe.
In one embodiment, the projectile comprises novel features as defined in the claims.
In another embodiment, the present invention provides a method of using the pyrophoric substance so that the projectile is fire-safe.
This invention will be described by way of non-limiting embodiments of the present invention, with reference to the accompanying drawings, in which:
One or more specific and alternative embodiments of the present invention will now be described with reference to the attached drawings. It shall be apparent to one skilled in the art, however, that this invention may be practiced without such specific details. Some of the details may not be described at length so as not to obscure the invention. For ease of reference, common reference numerals or series of numerals will be used throughout the figures when referring to the same or similar features common to the figures. Front/forward or rear orientation of any component is with respect to the travel direction of the projectile.
The front exterior of the nose cap or ogive 110 is substantially hemispherical in shape and it extends to its rear 116 in a cylindrical shape. As can be seen from
A front end 141 of the projectile body 140 has a recess 146 at its center, with respect to the center axis C. The recess 146 is cylindrical in section and has a closed bottom. The exterior surface of the projectile body 140 located between the connections with the nose cap 110 and the cartridge case 160 has two projected rings 147. The ring surfaces have substantially the same exterior dimension as the cylindrical surface of the nose cap 110 so that they fit with a bore of a launcher (not shown in the figures) to spin stabilize the projectile 100 during launch and flight to the target.
As seen in
Still referring to
In another embodiment 100c, the shield 180 and support ring are integrally formed from one piece, for example, with corrugations like those paper cups for muffins;
In use, after the projectile 100, 100a, 100b, 100c is ejected from a launcher, the projectile 100, 100a, 100b, 100c experiences large acceleration and spin forces; as a result, the impulse imparted onto the glass vial 124 in the ampoule 122 causes the vial to break and the first and second chemiluminescent dye components 123,125 to mix within the ampoule 122 and react with each other. The spin forces also cause turbulent mixing of the first and second chemiluminescent dye components 123,125 to give a luminous glow, even when the projectile 100, 100a, etc is in flight. When the projectile 100, 100a, 100b, 100c hits its target, the impact of the projectile 100, 100a, 100b, 100c causes both the plastic nose cap 110, the ampoule 122 and the capsules 170 to break. As a result, the dye powder 126, the glowing chemiluminescent dye material and pyrophoric substance are dispersed at the point of impact. When the pyrophoric substance is released from the capsules 170, the material begins to oxidize and emits an infra-red signal that is detectable with suitable IR detection devices, such as night vision goggles or thermal imaging cameras. The impact forces also cause the dye powder 126 to sputter and to provide a visible effect at the point of impact during day-time training. The sputtering of the dye powder 126 carries with it the chemiluminous dye, causing the point of impact to be more visible from a distance.
In the above embodiments, ballistic performance of the projectiles 100,100a,100b, 100c is desirably as close as possible to the ballistic performance of projectiles in service. To achieve this, tests with projectiles made of different materials and mass distributions of the components were carried out. In addition, safety tests, such as drop test, were carried out to ensure that these projectiles 100,100a, 100b, 100c are strong enough to withstand handling during transportation and foreseeable types of mishandling.
While specific embodiments have been described and illustrated, it is understood that many changes, modifications, variations and combinations thereof could be made to the present invention without departing from the scope of the present invention. For example, a large caliber projectile may be similarly configured like the above projectiles for both day and night strike point marking. In another example, a grenade may also be similarly configured according to the teaching of the present invention. In another example, the materials of the ampoule and vial are not limited, respectively, to plastic and glass; they Can be made of other materials to store the chemiluminescent dye components.
Claims
1. A projectile having an elongate body, which defines a longitudinal axis, with a front portion being connectable to a hollow nose cap and a rear portion connectable to a cartridge case, the projectile comprising:
- an ampoule disposed inside the hollow nose cap, with the ampoule's longitudinal axis substantially coaxial with the longitudinal axis of the projectile, and the ampoule containing a first luminescent dye component;
- a vial disposed inside the ampoule, with the vial containing a second luminescent dye component;
- a dye powder filing a cavity between the hollow nose cap, the ampoule and the front portion of the projectile body; and
- one or more capsules containing a pyrophoric substance, with the one or more capsules being disposed in the dye powder and at the front portion of the projectile body;
- wherein, upon the projectile striking a target, the nose cap and the one or more capsules become broken, thereby allowing the pyrophoric substance to oxidize and to emit an infrared signal to mark the point of impact.
2. The projectile according to claim 1, further comprising a support ring to maintain the one or more capsules at the front end of the projectile body.
3. The projectile according to claim 2, further comprising a shield disposed between the one or more capsules and the ampoule.
4. The projectile according to claim 2, wherein the support ring and the shield are made of paper.
5. The projectile according to claim 4, wherein the support ring and shield are mortised or glued together.
6. The projectile according to claim 4, wherein the support ring and shield are integrally formed in one piece by corrugations.
7. The projectile according to claim 4, wherein the shield is cylindrical and the support ring is constituted by flaps folded out from one end of the cylindrical shield.
8. A method of marking a strike point of a projectile with an infra-red signature, the method comprising:
- breaking a nose cap on a projectile and one or more capsules containing a pyrophoric substance by impact forces after the projectile strikes a target or ground, and allowing the pyrophoric substance to oxidize for a short duration of time so that the infra-red signature is detectable by a thermal camera, yet keeping the broken projectile fire-safe.
9. A use of an infra-red emitter using a pyrophoric substance having a short burn duration in a fire-safe projectile.
Type: Application
Filed: Apr 15, 2015
Publication Date: Feb 16, 2017
Inventors: Cheng Hok AW (Singapore), Boon Siong CHONG (Singapore), Renjie XIE (Singapore), Miguel ORTEGA (Coachella, CA), Rachel Hendrika NEWELL (Coachella, CA)
Application Number: 15/304,067