Method and arrangement for artillery missiles

Abstract

The present invention relates to a method and an arrangement for shells ( 1 a, 1 b ) fired from launch weaponry, using some of the barrel pressure built up in the barrel during the launch phase for an additional active function over and above that of giving the shell ( 1 a, 1 b ) in question its trajectory velocity. According to the invention, during the launch phase, some of the propellant powder gas accelerating the shell is therefore introduced into a chamber ( 12, 38, 60 ) which is arranged in the same and which is delimited in at least one direction by an element ( 8, 31, 58, 52, 53 ) which is movable relative to the rest of the shell and on which the barrel pressure acting on the shell simultaneously acts to maintain the original direction as long as the shell is located inside the barrel during the launch phase. This technique can thus be used to remove protective casings covering the fins, in order to push out fin units and to deploy initially retracted fins.

1 . Method applied to missiles fired from launch weaponry, for example shells ( 1   a ,  1   b ) etc., and using some of the powder gases generated in the barrel during the launch phase for an additional active function over and above that of giving the shell ( 1   a ,  1   b ) in question its trajectory velocity, characterized in that, during the launch phase, some of the propellant powder gas accelerating the shell is introduced into a chamber ( 12 ,  38 ,  60 ) which is arranged in the same and which is delimited in at least one direction by an element ( 8 ,  31 ,  58 ,  52 ,  53 ) which is movable relative to the rest of the shell and on which the barrel pressure acting on the shell simultaneously acts to maintain the original direction as long as the shell is located inside the barrel during the launch phase, after which the propellant gases in the chamber are used, as soon as the external counterpressure ceases, to activate an active displacement between two components included initially in the missile.  
     
     
         2 . Method according to  claim 1 , characterized in that the propellant powder gases introduced into said chamber inside the shell ( 1   a ,  1   b ) are used to activate and force through a relative displacement between the main part of the shell ( 1   a ,  1   b ) and said movable elements ( 8 ,  31 ,  58 ,  52 ,  53 ) immediately after the shell has left the barrel and the counterpressure of the propellant powder gases has begun to be equalized in relation to the atmospheric pressure.  
     
     
         3 . Method according to  claim 1  or  2 , characterized in that the propellant powder gases are introduced into said chamber ( 12 ,  38 ,  60 ) via an inlet ( 13 ,  39 ,  61 ) which is dimensioned in such a way that, when the counterpressure drops to normal atmospheric pressure outside the barrel, the propellant powder gases introduced at high pressure into said chamber do not have time to be equalized at the same rate but instead give rise to the desired relative displacement.  
     
     
         4 . Method according to any of claims  1 - 3  in which, after said shell ( 1   a ,  1   b ) has been fired from the barrel provided for this purpose, a protective casing ( 8 ,  58 ) is removed which during the launch phase covers at least part of the rear part of the shell ( 1   a ,  1   b ) situated behind the drive band ( 2 ,  43 ) of the shell, characterized in that some of the powder gases driving the shell through the barrel in the launch phase are allowed to leak into a space ( 12 ,  60 ) provided for this purpose inside the protective casing ( 8 ,  58 ).  
     
     
         5 . Method according to any of claims  1 - 3  in which, after a shell ( 1   a ,  1   b ) has been launched from a barrel provided for this purpose, it is possible for a fin unit ( 31 ), initially located inside the shell, to be pushed rearwards relative to the direction of flight of the shell to the trajectory position of the fin unit, with the fins ( 32 ) behind the rear plane of the shell ( 1   b ) during the launch phase, characterized in that some of the propellant powder gases driving the shell ( 1   b ) through the barrel are introduced during the launch phase into a chamber ( 38 ) which is arranged inside the shell and whose boundary wall forms part of the fin unit ( 31 ) which is axially movable within the shell and on whose opposite side the barrel pressure acts for as long as the shell ( 1   b ) is located inside the barrel during the launch phase.  
     
     
         6 . Method according to any of claims  1 - 3  in which, after a shell ( 1   a ) has been launched from a barrel provided for this purpose, it is possible to deploy a plurality of fins ( 52 ,  53 ) which are arranged in the rear part of the shell and which, from a retracted position, can be forced out transverse to the direction of flight of the shell, characterized in that during the launch phase the fins ( 52 ,  53 ) are kept retracted by a casing ( 58 ) covering the rear part of the shell, in that this casing is removed by means of some of the powder gases driving the shell being introduced into the casing ( 58 ) during the launch phase, and in that after the casing has been removed the remaining powder gas pressure is used to force out the fins ( 52 ,  53 ).  
     
     
         7 . Arrangement which can be used, in conjunction with the method according to any of claims  1 - 6 , in shells ( 1   a ,  1   b ) fired from launch weaponry, using the barrel pressure built up in the barrel during the launch phase to implement an active function over and above that of giving the shell the necessary trajectory velocity, characterized in that it comprises a chamber ( 12 ,  38 ,  60 ) which is arranged inside the shell and which is delimited in at least one direction by a movable object ( 8 ,  58 ,  31 ,  52 ,  53 ) which, in the original position during the launch phase of the shell from the barrel, is acted upon from outside by the propellant powder pressure in the barrel, and an inlet ( 61 ) which leads to said chamber from that part of the shell which, viewed in the direction of flight, is situated behind its drive band ( 43 ), and through which inlet ( 61 ) some of the barrel pressure during the launch phase gains access to the chamber ( 60 ).  
     
     
         8 . Arrangement according to  claim 7 , characterized in that said inlet ( 61 ) is so dimensioned that the pressure which is able to build up inside the chamber ( 60 ) during the launch phase of the shell ( 1   a ), by means of propellant gases leaking into the chamber after the shell has left the barrel and the barrel pressure behind the shell is equalized in relation to the atmospheric pressure, cannot be regulated in the same way before said movable object ( 52 ,  53 ) has been displaced by the same pressure to the desired final position.