Patent GB-1399963-A (GB)
Title: Automatic firing weapon
IPC: F41A5/18
Filed: 1973-09-06
Abstract: 1399963 Automatic firing weapon WERKZEUGMASCHINENFABRIK OERLIKONBUHRLE AG 6 Sept 1973 41974/73 Heading F3C An automatic firing weapon comprises a housing 1, Fig. 1, a breechblock body 18, a breechblock carrier 11 which is displaceably mounted in the housing 1, a safety lever 70, Fig. 6, which is mounted in the housing 1, Fig. 1, and a movable barrel 2. The safety lever 70 co-operates with a stop 57, Fig. 6, on the carrier 11 to prevent recoil movement of the carrier and a cam 65, Fig. 5, of the lever 70 is engageable with a control surface 69 on the barrel 2 which, when the weapon is fired effects the release of the lever 70 from the stop 57, Fig. 6, and allows the carrier to move rearwardly. The safety lever 70 and its cam 65 are mounted on a common shaft 64 along with an unlocking lever 79, Fig. 7. The barrel 2, Fig. 1, is displaceably mounted in part 3 of the housing 1. A sleeve 4 is connected to the barrel 2 and has a flange 5 with grooves 9, Fig. 2, therein which receive projections 10. The carrier 11 is urged by a spring 12, Fig. 1, and has a head 16 with a bore 17 having the breechblock body 18 slidably mounted therein. The latter has a ring 19, Figs. 2 and 3, having grooves 20 and projections 21. The body 18, Fig. 1, has a bore 22 with a firing pin 23 therein and has a bore 24 with a bolt 25 therein, the firing pin penetrating through the bolt so as to pivotally secure the latter. Each end of the bolt 25 extends into a respective slot 26 in the head 16. A sleeve 29, secured to the barrel 2, has a flange 30 and an extension 31. A plunger 32 is connected to the extension 31. A nozzle 33 is mounted in the wall of the barrel 2. A bore 34 of the nozzle 33 merges with a bore 35 in the plunger 32. A cylinder 36 is secured at a wall 37 of the housing 1 and is retained by a support 38 connected with the housing 1. A piston 39 is in the cylinder 36 and is urged by a spring 40 and a piston-rod 41 extends through the wall 37. The plunger 32 is displaceably mounted at the base of the cylinder 36. The latter has a bore 42 which passes through its wall into a chamber 43. The carrier 11 has a fork-shaped foot 44 with a recess 45, Fig. 7. An entrainment member 46, Fig. 4, extends through a slot 47 in the foot 44 and has a projection 48 located in front of base 49, Fig. 7, of the recess 45. The projection 48 is displaceably mounted on a rod 50, Fig. 4, is urged by a spring 51, Fig. 1, and is connected to a chain 52. A projection 53, Fig. 7, of the projection 48 extends into a slot 54 in the foot 44 and is provided with an inclined surface 55. The foot 44 has a groove 56, Fig. 1, having an inclined surface 57, Fig. 6. A support 58, Fig. 4, is attached to portion 1a of the housing 1 and is provided with recesses 59, 60, and 61 also with a bore 62 which opens into said recesses. In the section of the bore 62 between recesses 59 and 60 there is rotatably mounted a bushing 63 with a notchedtoothed bore. A shaft 64 is received in the bore 62 and is keyed with the bushing 63 and with the cam 65, the latter 65 extends through a slot 66, Fig. 5, in the housing 1. A projection 67 is provided on the barrel 2 and has a cylindrical surface 68 which is connected to the surface of the barrel by the conical surface 69. The safety lever 70, Fig. 6, is mounted in the recess 60 of the support 58. A spring 72, in a bore 71 of the support 58, urges a surface 73 of the lever 70 against the support 58. The lever 70 extends through a slot 74 in the housing portion la into the path of the support 11. A coupling 75, Fig. 7, is positioned in the recess 61 of the support 58 and has an extension 77 having a surface 78 thereon. The recess 61 also contains the unlocking lever 79 which is urged by a spring 82 and, extending through a slot 84, engages the housing portion la. In operation the firing pin 23 penetrates the cap of cartridge 86, Fig. 1, and the head 16 of the carrier 11 is impacted against the sleeve 4, this causing the radial symmetry planes of the projections 10 and 21, Fig. 2, of the sleeve 4 and the breechblock body 18 to coincide. The ends of the bolt 25, Fig. 1, are located at the rear portion 27 of the slot 26 of the head 16 and the rear end of the plunger 32 bears against the piston 39. The cam 65, Fig. 5, engages the surface 69 of the barrel 2 and the safety lever 70, Fig. 6, extends into the groove 56 of the carrier 11. The surface 70a of the safety lever 70 is located behind the surface 57 of the groove 56 and the surface 78, Fig. 7, of the coupling 75 bears against the surface 81 of the lever 79. When the carrier 11, Fig. 1, recoils its surface 57, Fig. 6, impacts against the surface 70a of the lever 70, the counterclockwise movement of the latter causing locking thereof. During recoil of the carrier 11, the linear portion 27, Fig. 1, moves along the ends of the bolt 25 so that the breechblock body 18 is not rotated and remains locked with the barrel 2. Gas pressure acts, via the cartridge sleeve 90 and the breechblock body 18, upon the sleeve 4 of the barrel 2 thus causing the conical surface 69, Fig. 5, of the barrel 2 to move the cam 65. The shaft 64 rotates, thus moving the lever 70 in the clockwise direction. When the cam 65 contacts surface 68 of the barrel, the lever 70 has left the groove 56 of the carrier 11. The piston-rod 41 is moved by the plunger 32 towards the foot 44. The lever 79 remains unmoved. Gas flows through bores 34, 35, Fig. 1, of the nozzle 33, through the projection 31 and the plunger 32 and into the chamber 43. This causes acceleration of the piston 39 and the carrier 11, the piston 39 then moving away from the plunger 32. The bolt 25 impinges against the inclined portion 28 of the slot 26 so as to rotate the breechblock body 18 and to cause its projections 21 to move along the projections 10 of the sleeve 4. The piston 39 is braked but the carrier 11 continues to move to the rear of the weapon. The piston is now located behind the bore 42, gas flows from the chamber 43 to ambient, and the piston 39 is returned by the spring 40. The rotation of the breechblock body 18 causes the symmetry planes of its projections 21 and the grooves 9 of the sleeve 4 to coincide so that the breechblock body 18 is unlocked from the barrel 2. The bolt 25 is moved, by the breechblock body 18, at the velocity of the carrier 11, the projection 21 extend through the grooves 9 and the empty cartridge sleeve 90 is removed from the barrel 2. After the carrier 11 has hit the buffer 15, it is moved by the spring 12 towards the front of the weapon and the breechblock body 18 introduces a new cartridge 86 into the barrel 2, the return movement of the carrier being limited by a stop 88 of the housing 1. The cam 65, safety lever 70, projections 18, grooves 9, carrier 11, the bolt 25 and the breechblock body 18 return to their former positions shown in the drawings and the breechblock body 18 is again locked with the barrel 2. Cocking is effected by pulling chain 52, Fig. 1, this rotating the unlocking lever 79, via a cam 53, Fig. 7. The lever 79 is moved clockwise against spring 82. Shaft 64 and consequently lever 70 and cam 65 are rotated. The carrier 11 is moved rearwards by entrainment member 46 which engages the foot 44 of the carrier 11, and the breechblock body 18 is unlocked from the barrel 2.