Method and launcher for launching a projectile

Abstract

The invention relates to a method for launching a projectile and a launcher comprising a barrel (1) accommodating a. a projectile (2); b. a rocket motor (13) at the rear end of the projectile (2) comprising a first compartment containing a first propellant; c. a countermass (3) at the rear end of the barrel (1); and d. a second compartment between the rocket motor (13) and the countermass (3) containing a second propellant, wherein said first and second compartments form a high pressure chamber (6) subsequent to firing of the projectile (2).

Claims

1. Method for launching a projectile (2) from a barrel (3) accommodating a. a projectile (2); b. a rocket motor (13) at the rear end of the projectile (2) comprising a first compartment (6) containing a first propellant (10); c. a countermass (3) at the rear end of the barrel (1); and d. a second compartment (6) between the rocket motor (13) and the countermass (3) containing a second propellant (11), wherein said first and second compartments (6,6) form a high pressure chamber (6) subsequent to firing of the projectile (2); i) wherein combustion gases originating from propellants contained in said first and second compartments (6,6) in said high pressure chamber (6) accelerate the projectile (2) in the firing direction and the countermass (3) in the opposite direction towards a breech; and ii) wherein the pressure in the high pressure chamber (6) falls in the second compartment to a level below the pressure in the first compartment when the countermass (3) leaves the barrel (1); and iii) wherein said first compartment upholds substantially the originally formed pressure by means of an opening of said first compartment delimiting the exhaust of gases from the first compartment to the second compartment, thus enabling continued acceleration of the projectile (2) after the countermass (3) has exited the barrel (1).

2. Method according to claim 1, wherein the countermass (3) is a metal grit.

3. Method according to claim 1, wherein the opening is a nozzle.

4. Method according to claim 1, wherein the opening is a ring nozzle.

5. Method according to claim 1, wherein a cartridge case (8) radially encloses components a) to d) according to claim 1.

6. Method according to claim 1, wherein a pressure sealing is provided between the cartridge case (8) and the barrel (1) at the rearmost part of the cartridge case (8).

7. Method according to claim 1, wherein a flight motor (14) is integrated in the projectile (2) in front of the rocket motor (13).

8. Launcher comprising a barrel (1) accommodating a. a projectile (2); b. a rocket motor (13) at the rear end of the projectile (2) comprising a first compartment containing a first propellant; c. a countermass (3) at the rear end of the barrel (1); and d. a second compartment between the rocket motor (13) and the countermass (3) containing a second propellant, wherein said first and second compartments form a high pressure chamber (6) subsequent to firing of the projectile (2); wherein a cartridge case (8) is arranged inside the barrel (1) extending from the rear end of the projectile (2) to the rear part of the countermass (3).

9. Launcher according to claim 8, wherein a driving band (5) is positioned between the rearmost part of the countermass (3) and the barrel (1).

10. Launcher according to claim 8, wherein means (7) for affixing the countermass (3) and the cartridge case (8) to the barrel (1) is arranged at the rearmost section of the countermass (3).

11. Launcher according to claim 8, wherein at least three compartments for propellants are arranged between the rear end of the projectile (2) and the countermass (3).

12. A recoilless weapon according to claim 8, wherein the weapon is a hand-held, platform mounted or a free-standing weapon.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1a illustrates a barrel accommodating a projectile and a countermass.

(2) FIG. 1b illustrates a conventional arrangement in a barrel accommodating a countermass and a projectile.

(3) FIGS. 2a and 2b illustrate a projectile with a cartridge case with wrapped-around fins in unfolded position.

(4) FIG. 3a illustrates a barrel accommodating a rocket motor in which a first compartment is arranged.

(5) FIGS. 3a-d illustrate different sub-phases during the internal ballistics phase.

(6) FIG. 4 shows a barrel accommodating a tandem projectile.

(7) FIG. 5 illustrates a barrel accommodating a flight motor in which a third propellant is enclosed.

DESCRIPTION OF THE DRAWINGS

Detailed Description of Various Embodiments

(8) FIG. 1a illustrates a barrel 1 accommodating a projectile (tandem shell) 2 and a countermass 3 at the rear end of the barrel 1. In FIG. 1a, also a propellant case 4 is shown next to the countermass 3. A cartridge case 8 is shown resisting the pressure built up in the forming high pressure chamber 6. The barrel 1 can then be less rigorously designed but needs to resist the pressure remaining at the point in time the projectile 2 and the cartridge case 8 are leaving the barrel 1.

(9) The cartridge case 8 is surrounding the accommodated parts in the barrel 1 extending from the rear end of the projectile 2 to the rear part of the countermass 3. A driving band 5 is arranged at the rearmost section of the barrel contributing to the formation of a high pressure chamber 6 between the projectile 2 and the cartridge case 8. As the driving band 5 is attached to the cartridge case 8 at the rear end thereof, the distance it travels is equal to the length of the barrel 1, in this particular case 980 mm. The countermass 3 consists of steel grit with a total weight of 1 to 4 kg. Means 7 affixing the countermass 3 is arranged at the rear end of the cartridge case 8.

(10) FIG. 1b illustrates a conventional arrangement in a barrel 1 accommodating a countermass 3 and a projectile 2. As opposed to the arrangement in FIG. 1a, the driving band 5 is arranged at the rear part of the projectile 2 whereby the distance it travels is only 430 mm in the same barrel 1, i.e. less than halfway of the driving band 5 in FIG. 1a.

(11) FIGS. 2a and 2b show a projectile 2 with a cartridge case 8 with wrapped-around fins 12 in unfolded position, seen from behind and from the side respectively. The cartridge case 8 is the same as in FIG. 1a. The cartridge case 8 inside the barrel 1 is provided with wrapped-around fins 12 at its rearmost section. The cartridge case 8 may thus function as a holder of fins 12 to which the fins 12 are secured.

(12) FIG. 3a shows a barrel 1 accommodating a rocket motor 13 in which a first compartment 6 containing a first propellant 10 is arranged between a projectile 2 and a countermass 3 in a cartridge case 8. A second propellant 11 is enclosed in a second propellant case 4. The second propellant 11 is in communication with the first propellant 10 subsequent to firing since a separating lid of the second propellant is burnt and eliminated. The propellant 10 in the first compartment, typically a rocket propellant is ignited subsequent to ignition via the second propellant 11.

(13) FIGS. 3a-d illustrate different sub-phases during the internal ballistics phase. In FIG. 3a, prior to ignition of propellant, the countermass 3 is in the rear end of the barrel 1 and all other components are positioned next to one another next to the countermass 3. In FIG. 3b, the countermass 3 and the projectile 2 have traveled inside the barrel 1. The countermass 3 is still partially inside the barrel 1 whereby the internal ballistic pressure is upheld in the high pressure chamber 6 made up of compartments 6 and 6. In FIG. 3c, the countermass 3 has exited the barrel 1. The rocket motor phase has been initiated. The pressure has dropped considerably in the second compartment 6 whereas an overpressure is still upheld in the first compartment 6 due to propellant combusted in the rocket motor and a rocket motor nozzle restricting the exhaust of combusted propellant. In FIG. 3d, the rear part of the cartridge case 8 is about to leave the barrel 1. The propellant should have been combusted prior to the point in time the projectile 2 leaves the barrel 1 for reasons of security of the operator.

(14) FIG. 4 shows a barrel 1 accommodating a tandem projectile 2 equipped with a launch rocket motor 13 formed with a ring nozzle design.

(15) FIG. 5 illustrates a barrel 1 accommodating a flight motor 14 in which a third propellant 15 is enclosed. An alternative projectile 2 is illustrated. The flight motor 14 is positioned in front of the launch rocket motor 13 (in FIG. 4) at the rear end of the projectile 2. The flight motor 14 is ignited by an ignition sequence connected to the rocket motor 13.

(16) The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the gist and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the claims.