Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
  • F42B12/00—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material
  • F42B12/02—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the warhead or the intended effect
  • F42B12/36—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the warhead or the intended effect for dispensing materials; for producing chemical or physical reaction; for signalling ; for transmitting information
  • F42B12/56—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the warhead or the intended effect for dispensing materials; for producing chemical or physical reaction; for signalling ; for transmitting information for dispensing discrete solid bodies
  • F42B12/58—Cluster or cargo ammunition, i.e. projectiles containing one or more submissiles
  • F42B12/62—Cluster or cargo ammunition, i.e. projectiles containing one or more submissiles the submissiles being ejected parallel to the longitudinal axis of the projectile
  • F42B12/64—Cluster or cargo ammunition, i.e. projectiles containing one or more submissiles the submissiles being ejected parallel to the longitudinal axis of the projectile the submissiles being of shot- or flechette-type
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F42—AMMUNITION; BLASTING
  • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
  • F42B12/00—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material
  • F42B12/02—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the warhead or the intended effect
  • F42B12/36—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the warhead or the intended effect for dispensing materials; for producing chemical or physical reaction; for signalling ; for transmitting information
  • F42B12/56—Projectiles, missiles or mines characterised by the warhead, the intended effect, or the material characterised by the warhead or the intended effect for dispensing materials; for producing chemical or physical reaction; for signalling ; for transmitting information for dispensing discrete solid bodies
  • F42B12/58—Cluster or cargo ammunition, i.e. projectiles containing one or more submissiles
  • F42B12/62—Cluster or cargo ammunition, i.e. projectiles containing one or more submissiles the submissiles being ejected parallel to the longitudinal axis of the projectile

Definitions

• the technical field of the invention is that of the gyro-stabilized projectiles comprising a body containing a payload formed of a set of subprotectable dispersible trajectory by a pyrotechnic charge.
• projectiles are usually medium caliber projectiles (caliber between 20mm and 70mm) and are used as part of the anti-aircraft defense.
• Sub-projectiles are usually metal spheres or cylinders, such as steel or tungsten.
• the dispersion of the sub-projectiles in front of a target makes it possible to destroy the latter.
• Patent GB460516 discloses a particular projectile whose body contains seven complete cartridges each comprising a case and a bullet positioned in a striped tube.
• the cartridges are immobilized relative to the body at their rear base which bears against a stop plate.
• Each cartridge has a primer that is struck by a striker pushed by a piston.
• a pyrotechnic charge is initiated on trajectory and pushes the piston against the action of a spring, causing the percussion of the primers of the cartridges, thus the firing of the bullets.
• the cartridges cartridges remain in the body after the shooting of the latter.
• Such a system is complex and only the balls, so a small part of the payload, are ejected.
• Patent CH85741 discloses a projectile for the destruction of balloons or airships which comprises various pyrophoric sub-projectiles which are ejected out of the body of the projectile after having been themselves initiated. The ejection is caused after a delay by the initiation of a charge. This charge is not a detonation relay because it is initiated by a charge of slow combustion powder (pyrotechnic delay) whose output can initiate a pyrotechnic composition or a charge of black powder.
• pyrotechnic delay slow combustion powder
• Patent US3954060 discloses a projectile comprising a stack of metal darts which are dispersed by means of a pyrotechnic charge generating a gas pressure.
• the bullet of the projectile Prior to the expulsion, the bullet of the projectile is cracked and opens in petals following the action of another pyrotechnic device.
• the sub-projectiles are housed in several one-piece buckets stacked on top of each other from the rear of the shell body into the warhead.
• a rear piston is attached to the shell body and pushes the godets out of the body once the warhead and its contents ejected.
• Patent EP0698774 also discloses a projectile in which the dispersion of the sub-projectiles is obtained by the initiation, not of a gas-generating composition, but of an explosive charge which is separated from the payload by a partition .
• the body casing is sheared radially at the bulkhead and the body opens at the rear along longitudinal breakouts.
• the object of the invention is to provide a projectile architecture of simple design and yet reliably ensuring axial and forward ejection of the sub-projectiles. Thanks to the invention this ejection is carried out with a speed which is increased relative to the residual velocity of the projectile. About 40m / s are also provided on a speed of the order of 500 to 800 m / s, an increase of 5% to 8% in the speed of the sub-projectiles.
• the subject of the invention is a gyrostabilized projectile comprising a body enclosing a payload formed of a set of sub-projectiles, dispersible on trajectory by the action of a pyrotechnic charge secured to a rear part of the body, the body carrying in its front part a ballistic warhead, the payload being completely ejected out of the body by the forward projection of the projectile of a piston slidably mounted in the body, projectile characterized in that the pyrotechnic charge is constituted by a relay detonation which is separated from the payload by the piston, the piston having a styling clearance and surrounding the detonation relay, the latter not being directly in contact with the piston.
• the piston will have an external profile corresponding to that of the inner housing of the body.
• the external profile of the piston may for example be hexagonal.
• the piston may have a thickness of between 7.5 mm and 10 mm.
• the payload may be arranged between the piston and a front thrust plate which is itself in abutment against the ogive.
• the front thrust plate may include an internal cavity having a hexagonal profile and receiving the payload.
• the projectile may include a bearing ring which will be integral with the body and on which the piston will be supported.
• Figure 1 is a longitudinal sectional view of an embodiment of a projectile according to the invention.
• FIG. 2 is a cross-sectional view of this projectile, cut along the plane AA whose trace is visible in FIG.
• a projectile 1 according to one embodiment of the invention comprises a body 2 which is closed at its front by a ballistic ogive 3 and at its rear by a base 4 screwed to the body 2.
• the body 2 comprises an inner housing 12 which encloses a payload 5 which is formed of a set of trajectory-dispersible sub-projectiles 6.
• the sub-projectiles 6 are steel or tungsten cylinders which are stacked in columns.
• the inner housing 12 of the latter has a hexagonal profile conforming to the contour of the cylindrical sub-projectiles.
• This hexagonal profile is the most suitable for driving cylindrical columns.
• Other shapes would of course be possible, for example cylindrical grooves regularly distributed angularly and each corresponding to a sub-projectile column.
• the hexagonal profile of the housing 12 has rounded grooves 12a at the vertices of the hexagon. These grooves 12a extend over the entire length of the body 2 and have a radius of curvature equal to that of the cylindrical subprojects 6.
• the housing 12 has a groove 12b at each middle of the sides of the hexagon. These grooves 12b extend over the entire length of the body 2 and each open on a cylindrical profile 12c receiving a subprotect column 6.
• each side of the hexagonal profile of the housing 12 comprises three sub-projectiles 6.
• the sub-projectile column 6 located in the middle of each side is thus maintained by a groove 12b.
• the base 4 encloses a rocket 7 which comprises in a conventional manner a safety and arming device and a detonator 8, the initiation of which is controlled by a programmable electronic module 9.
• This relay 10 is a detonating pyrotechnic charge which is initiated by the shock wave coming from the detonator 8 and which reacts in detonation.
• detonation is meant a self-sustaining exothermic chemical reaction in which a shock wave precedes the reaction front and travels at a speed greater than the sonic velocity of the composition.
• a detonation velocity is of the order of several thousand meters per second.
• Detonation relays are typically used to detonate an explosive charge, such as a shell.
• a relay 10 formed of compressed hexogen can be used.
• a gas generating composition is initiated in combustion, that is to say with a reaction rate of a few meters per second. It is the same for a propellant powder whose reaction rate is of the order of a few tens of meters per second.
• the detonation relay 10 is separated from the payload 5 by a piston 11 which is slidably mounted in the body 5.
• the piston will have a hexagonal outer profile to follow the hexagonal profile of the housing 12 of the body 2 and be rotated with the projectile which avoids the problems of gyroscopic instability.
• the housing 12 has another shape of profile, for example cylindrical grooves evenly spaced angularly, the piston 11 will have a profile corresponding to that of the housing 12 to be able to slide in the latter and be integral in rotation with the body 2.
• the payload 5 is disposed between the piston 11 and a front thrust plate 14 which is itself bearing against a shoulder 13 of the ogive 3.
• the thrust plate 14 has a shaped cup and thus has an internal cavity delimited by a thin wall 20.
• the wall 20 is interposed between the ogive 3 and the payload 5.
• This wall 20 is cylindrical and in contact with the ogive and the inner surface of this wall 20 has a hexagonal profile similar to that of the housing 12 of the body. It is through this profile that the thrust plate 14 is rotated by the payload 5. Such an arrangement ensures the stability of the projectile in flight by avoiding a rotation of the thrust plate 14 relative to the payload 5.
• the warhead 3 is fixed to the body 2 by a thread 15. It comprises a rupture groove 17 which will shear during the operation of the detonation relay 10 and allow the front ejection of the payload 5.
• the piston 11 comprises a recess 16 which caps and surrounds the detonation relay 10. The latter is not directly in contact with the piston 11. Such an arrangement allows not to damage the piston 11 during operation of the detonation relay 10.
• This clearance is essential for the proper operation of the frontal ejection by detonation. It has a depth of between 2 and 4mm.
• a support ring 18 is placed between the piston 11 and the rocket 7, its function is to recover the inertial forces of the payload 5 which apply to the piston 11 during firing. This makes it possible not to damage the rocket 7.
• This support ring 18 may be optional in the case where the recovery of the inertial forces of the payload 5 is ensured by a support of the piston 11 directly on a body of the body 2 of the projectile (scope not shown which would be arranged in place and place of the ring 18).
• the mounting of the projectile 1 is carried out as follows:
• the support ring 18 is screwed and glued to its proper position in the body 2.
• the piston 11 is then introduced into the body 2 by the front of the latter until it bears on the support ring 18, then the payload 5 is introduced into the body 2. It will be possible for this purpose, to make the sub-projectiles 6 fast with each other temporarily, for example with a plastic film surrounding the sub-projectile stacks 6.
• the front thrust plate 14 is then positioned on the payload 5 with the interposition of one or more axial pitching sheets 19, then the warhead 3 is screwed and glued onto the body 2 of the projectile.
• the base 4 enclosing the rocket and carrying the detonation relay 10 is finally screwed to the rear part of the body 2.
• the rocket 7 received before firing (or on trajectory) a programming of the moment of dispersion of the sub-projectiles 6. This programming is not part of the invention and it is therefore not necessary to describe it in detail.
• the detonator 8 is initiated by the electronic module 9. It causes the detonation of the relay 10.
• the shock wave from the relay 10 will cause the projection of the piston 11 towards the front of the projectile. This shock wave propagates through the piston 11, the payload 5 and the plug 14. It is sufficient to shear the rupture groove 17 of the nose 3 and also ensures the projection of the entire payload 5 through the front opening of the warhead 3 thus sheared.
• the piston In order to avoid any deformation or destruction of the piston 11 by impact, the piston will be given a thickness of between 7.5 mm and 10 mm.
• the shear of the ogive 3 is obtained reliably and quickly by the sole effect of the shock wave.
• the tests have shown that the shock also makes it possible to eject the payload axially without it being necessary to cut the body longitudinally and without the relative sealing between the piston 11 and the body 2 being necessary.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• General Engineering & Computer Science (AREA)
• Aiming, Guidance, Guns With A Light Source, Armor, Camouflage, And Targets (AREA)
• Radar Systems Or Details Thereof (AREA)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

Country Status (7)

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• 2012
  • 2012-11-23 FR FR1203211A patent/FR2998659B1/fr not_active Expired - Fee Related
• 2013
  • 2013-11-22 EP EP13820785.7A patent/EP2923171B1/de active Active
  • 2013-11-22 US US14/647,168 patent/US9423226B2/en active Active
  • 2013-11-22 WO PCT/FR2013/052823 patent/WO2014080136A1/fr active Application Filing
  • 2013-11-22 NO NO13820785A patent/NO2923171T3/no unknown
  • 2013-11-22 PT PT138207857T patent/PT2923171T/pt unknown
  • 2013-11-22 ES ES13820785.7T patent/ES2658992T3/es active Active

Non-Patent Citations (1)

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