EP0611196B1 - Ammunition for cannons, mortars and similar weapons with limited recoil energy - Google Patents

Description

The present invention relates to improvements made to ammunition for cannons, mortars and similar weapons equipped with a recoil damping device. It applies more particularly to high impulse munitions.

It is known that in ammunition of the above type such as currently produced, the peak operating pressure appears at the start of the projectile's path in the barrel, the projectile base and the bottom of the breech the weapon then supporting maximum accelerations.

These brutal starting accelerations result in a high speed setting of the cylinder head and of its damping device, which generates significant recoil energies which must be absorbed by the braking stroke of the recoil damping system, this braking stroke being , for a given braking force and compatible with the weapon system concerned, linked to the reversing speed to be absorbed.

This organization has the particular disadvantage of being cumbersome, cumbersome and limiting as regards the admissible recoil energies.

We know (US-A-4 335 657) an ammunition for cannons, mortars and similar weapons of the type comprising a shell containing a projectile, which comprises at least two propellant charges: a charge for ejecting the projectile and, at least one charge launching the projectile the latter being initiated by the hot pressurized gases from the complete combustion of the ejection charge and a system of chambers through which are released, in the passage of the projectile, the combustion gases of said charge d ejection, this system comprising: a first chamber receiving the combustion gases from the ejection charge and operating under high pressure a second annular chamber, or intermediate ignition chamber receiving the combustion gases from the projectile launch charge and ; a third chamber or main chamber for combustion and expansion of the munition, operating under a lower pressure than that prevailing in the first chamber and into which said second chamber opens.

Starting from this state of the art taken as the basis of the preamble of independent claim 1, the present invention proposes to increase the potential of these weapons by providing provisions making it possible to limit the recoil energies by implementing appropriate internal ballistics. .

• la charge d'éjection est positionnée dans un manchon solidaire de la douille contenant le projectile et débouchant dans ladite première chambre ;
• la charge de lancement est placée à l'extrémité dudit manchon, dans une structure concentrique à ce manchon et à l'extérieur de ce dernier, cette structure débouchant dans ladite seconde chambre, et en ce que cette dernière est inscrite entre le diamètre intérieur de queue du projectile et le diamètre extérieur de la structure de la charge de lancement.

Consequently, this invention relates to a munition of the type specified above, characterized in that:

• the ejection charge is positioned in a sleeve integral with the socket containing the projectile and opening into said first chamber;
• the launching charge is placed at the end of said sleeve, in a structure concentric with this sleeve and outside of the latter, this structure opening into said second chamber, and in that the latter is inscribed between the internal diameter of tail of the projectile and the outside diameter of the launch charge structure.

It is understood that, thanks to the arrangements provided by the present invention, which achieves appropriate internal ballistics, a progressive rise in the thrust force is obtained on the projectile and the breech of the weapon, which, given the simultaneous braking exerted by the recoil damping device, makes it possible to reduce the recoil speed of the barrel of the weapon and therefore its energy, while retaining the speed pulse communicated to the projectile, which ultimately makes it possible to obtain a reduction in the stroke of this recoil damping system.

According to a characteristic of the present invention, the structure containing the launch charge comprises peripheral ignition lights closed by an ignition composition and this structure is provided with an openwork shutter member, the nozzles of which provide ejection combustion gases from this launch charge.

According to one embodiment of the invention, the ammunition comprises a cruising propellant or a drag compensator, initiated by the combustion gases of the ejection charge filling said first chamber.

• la figure 1 est une vue en coupe longitudinale de la partie arrière d'une munition munie des perfectionnements objet de la présente invention,
• les figures 2 à 4 sont des vues schématiques, similaires à la figure 1 mais à plus petite échelle, illustrant les phases successives de fonctionnement de la munition selon l'invention et,
• la figure 5 est un schéma donnant les allures des courbes d'impulsion au départ du projectile, d'une part pour une munition classique et d'autre part, pour une munition selon la présente invention, à balistique étagée.

Other characteristics and advantages of the present invention will emerge from the description given below with reference to the appended drawings which illustrate an embodiment thereof devoid of any limiting character. In the drawings:

• FIG. 1 is a view in longitudinal section of the rear part of a munition provided with the improvements which are the subject of the present invention,
• FIGS. 2 to 4 are schematic views, similar to FIG. 1 but on a smaller scale, illustrating the successive phases of operation of the munition according to the invention and,
• FIG. 5 is a diagram giving the appearance of the pulse curves at the start of the projectile, on the one hand for a conventional ammunition and on the other hand, for an ammunition according to the present invention, with staged ballistics.

Reference is firstly made to FIG. 1 which represents the ammunition according to the present invention which comprises, as known, a cartridge case 1 containing the projectile 2 provided with a sealing ring 3.

• une charge d'éjection 4, contenant une petite masse de poudre initiée par une amorce 5 et qui est logée dans la partie arrière d'un manchon étanche 6, ce manchon 6 débouchant dans une chambre 7 destinée à recevoir les gaz de combustion de cette charge d'éjection 4. Dans cet exemple de réalisation, le projectile comporte un propulseur de croisière 8 dont l'allumage est activé par une peinture d'allumage 9, les gaz de combustion de ce propulseur de croisière étant admis dans la chambre 7. Ce propulseur de croisière peut être remplacé par un compensateur de trainée de type connu ;
• une charge principale de lancement 10 du projectile, contenant la masse de poudre qui est nécessaire à l'impulsion de lancement du projectile communiquant à ce dernier sa vitesse initiale. Cette charge 10 est placée dans une structure concentrique au manchon 6 et à l'extérieur de ce dernier, cette structure comportant des lumières d'allumage périphériques qui sont obturées par une composition d'allumage 11. Cette structure contenant la charge 10 comporte sur sa partie arrière un organe d'obturation 12 muni d'ajutages pour l'éjection des gaz de combustion de cette charge 10.

According to the present invention, the internal ballistics of the ammunition is organized by providing at least two propellant charges. In this nonlimiting exemplary embodiment, the ammunition comprises two charges:

• an ejection charge 4, containing a small mass of powder initiated by a primer 5 and which is housed in the rear part of a sealed sleeve 6, this sleeve 6 opening into a chamber 7 intended to receive the combustion gases of this ejection charge 4. In this exemplary embodiment, the projectile comprises a cruising propellant 8, the ignition of which is activated by an ignition paint 9, the combustion gases of this cruising propellant being admitted into the chamber 7. This cruising thruster can be replaced by a known type drag compensator;
• a main projectile launch charge 10, containing the mass of powder which is necessary for the projectile launch pulse communicating to the latter its initial speed. This charge 10 is placed in a structure concentric with the sleeve 6 and outside the latter, this structure comprising peripheral ignition lights which are closed by an ignition composition 11. This structure containing the charge 10 has on its rear part a shutter member 12 provided with nozzles for the ejection of the combustion gases from this charge 10.

• la première chambre 7 sur laquelle débouche le manchon 6 contenant la charge d'éjection 4, cette chambre 7 recevant donc les gaz de combustion provenant de l'allumage de cette charge d'éjection et éventuellement en outre, les gaz de combustion provenant du bloc de croisière 8 ou d'un compensateur de traînée ;
• une seconde chambre annulaire 13 ou chambre intermédiaire d'allumage qui est inscrite entre le diamètre extérieur de queue du projectile et le diamètre extérieur de la structure contenant la charge de lancement 10 ;
• une troisième chambre 14 qui constitue la chambre de combustion et de détente de l'arme et qui est délimitée par la douille 1 et la position du projectile muni de l'anneau d'étanchéité 3, la chambre annulaire d'allumage 13 débouchant sur cette troisième chambre 14.

As can be seen in the drawing, the improved ammunition according to the invention has three chambers:

• the first chamber 7 onto which the sleeve 6 containing the ejection charge opens, this chamber 7 therefore receiving the combustion gases originating from the ignition of this ejection charge and possibly also, the combustion gases originating from the block 8 cruise or drag compensator;
• a second annular chamber 13 or intermediate ignition chamber which is inscribed between the outside diameter of tail of the projectile and the outside diameter of the structure containing the launch charge 10;
• a third chamber 14 which constitutes the combustion and expansion chamber of the weapon and which is delimited by the socket 1 and the position of the projectile provided with the sealing ring 3, the annular ignition chamber 13 opening onto this third bedroom 14.

The operation of this munition will now be described with particular reference to FIGS. 2 to 4.

After ignition, from the initiation 5 causing the ignition of the ejection charge 4, the combustion gases of this charge 4 flow along the sleeve 6 and inside the latter in order to fill the chamber 7. If the ammunition comprises a cruising propellant 8 or a drag compensator, this propellant or this compensator is initiated by the combustion gases of the ejection charge 4, by means of the ignition paint 9. This phase of operation is illustrated in FIG. 2. During this phase of operation, the operating pressure is high and it is applied over a small section so that the resulting thrust is limited.

The pressure generated by the combustion and ignition gases filling the chamber 7 allows the projectile 2 to move inside the socket 1. For a given movement, the projectile 2 discovers in the intermediate ignition chamber 13, the second propellant charge 10, the initiation of which is provided by the ignition composition 11 which is contained in the cells peripheral to the structure containing the ignition charge 10, this initiation being carried out by the stream of hot gases and under pressure originating of chamber 7 and resulting from the combustion of the ejection charge 4 (and possibly in in addition to the cruising thruster 8 or a drag compensator), this stream of gas flowing from the periphery towards the interior of the load 10. This operating phase is illustrated in FIG. 2.

The gases produced by the ignition of the launch charge 10 are ejected by the nozzles of the shutter means 12, the latter thus ensuring a uniform gas flow inside the charge 10 and the maintenance of a certain pressure ignition, before the release of the main chamber 14 while the projectile continues its movement. The gases then fill the main chamber 14 as illustrated in FIG. 4, the seal being ensured by the ring 3. During this phase, the operating pressure is lower than during the previous phase but it applies to a section larger, which increases the launching pressure of the projectile giving it its initial speed.

It will be understood from reading the above description that the present invention makes it possible to modify the interior ballistics of a munition by providing at least two pulse stages, for launching the projectile, which ensures a reduction in the recoil energies.

• La courbe 1 se réfère à un projectile à balistique intérieure classique et,
• La courbe 2 se réfère à un projectile à balistique étagée selon la présente invention, comportant deux étages comme décrit ci-dessus.

FIG. 5 shows an example of the shape of the curves giving the thrust force exerted on the projectile and on the breech of the weapon, as a function of time:

• Curve 1 refers to a conventional interior ballistic projectile and,
• Curve 2 refers to a stepped ballistic projectile according to the present invention, comprising two stages as described above.

We see that in the case of curve 1, the recoil stroke is 730 mm while in the case of curve 2, this stroke is limited to 552 mm, for the same speed of the projectile and the same braking force.

The ammunition improved according to the present invention can be used in a long gun as described and claimed by the present holder in his patent application filed on the same day as the present application and entitled "long gun for firing ammunition with strong impulse ".

It remains to be understood that the present invention is not limited to the exemplary embodiments described and / or shown here but that it encompasses all the variants claimed.

Claims (3)

1. Munition for guns, mortars and similar weapons equipped with a recoil damping system, of the type comprising a casing containing a projectile, which comprises:

   - at least two coaxial propulsive charges;

   an ejection charge (4) for the projectile (2),

   at least one launching charge (10) for the projectile, this charge being initiated by the hot pressurized gases resulting from the complete combustion of the ejection charge (4);

   - a system of chambers, through which are released, as the projectile passes, the combustion gases from said ejection charge, this system comprising:

   a first chamber (7) receiving the combustion gases from the ejection charge (4) and operating at high pressure,

   a second, annular chamber (13) or intermediate ignition chamber receiving the combustion gases from the launching charge (10) of the projectile and;

   a third chamber (14) or principal combustion and expansion chamber for the munition, operating under a lower pressure than that existing in said first chamber (7), into which said second chamber leads, characterized in that

   - the ejection charge (4) is positioned in a sleeve (6) integral with the casing (1) containing the projectile and leading into said first chamber (7);

   - the launching charge (10) is placed at the end of said sleeve, in a structure concentric to this sleeve and outside it, this structure leading into said second chamber (13), the latter being inscribed between the internal diameter of the tail of the projectile and the external diameter of the structure of the launching charge (10).
2. Munition according to claim 1, characterized in that the structure containing the launching charge (10) comprises peripheral ignition apertures (11) obturated by an ignition composition and this structure is provided with a perforated obturation element (12), the nozzles of which ensure the ejection of the combustion gases from this launching charge.
3. Munition according to one of claims 1 or 2, characterized in that the munition contains a cruising propulsion system (8) or a trail compensator, initiated by the combustion gases of the ejection charge (4) filling said first chamber (7).

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