ES419532A1 - Automatic firearm with gas actuated breech mechanism - Google Patents

Abstract

Improvements in automatic weapons, particularly of small or medium caliber, with cylinder head mechanism commanded by gas intake and comprising, among other elements: a cylinder head block (1), with reciprocating longitudinal movement, requested towards its closing position by at least by a recovery spring (3); at least one retractable bolt (5) appropriate to provisionally immobilize this cylinder head block in the closed position; a maneuvering piece (7), with reciprocating longitudinal movement, which partially wraps said cylinder head block and which has, with respect to the latter, a degree of longitudinal sliding freedom that allows said maneuvering piece (7) (when it is in the anterior extreme position) locking said retractable bolt (5) in the active position; and at least one receiver apparatus that works by taking gases in the gun tube and that includes a mobile control unit (10) that slides longitudinally and is capable of causing, when its recoil stroke takes place, at first, the recoil of the mentioned maneuvering piece (7) with respect to the cylinder head block (1) and the release of the retractable bolt (5) and later, in a second time that intervenes after the bolting of said bolt and before the piece maneuver (7) has completed its entire possible recoil stroke with respect to the cylinder head block (1), the recoil of said cylinder head block, characterized in that the maneuvering part (7) of its cylinder head mechanism comprises at least one longitudinal housing (12) open forwards and laterally towards the interior and towards the exterior of the weapon, in which a control slide (13) is mounted, free to move forward with respect to said maneuvering piece (7) but stopped backwards, by supporting a rear support surface (S1) against the bottom (F1) of said housing, said control slide (13) comprising, towards the front, a front stop surface (S2) that forms a projection forward at the periphery of the maneuvering piece (7) being on the return path of the corresponding mobile control unit (10), and, on its side facing the interior of the weapon, a protrusion (13b) that forms a projection in the direction of the cylinder head block (1) through the internal lateral opening of the housing (12) of the slide (13) in question, said protuberance (13b) comprising a rear engagement notch (13c,) suitable for contacting a rear shoulder (E1) integral with the cylinder head block (1) and located (assuming the slider in the anterior extreme position) behind said engagement notch at a distance (D1) from the latter at least equal to and preferably greater than the recoil stroke that the control piece (7) of the cylinder head mechanism must travel to release the bolt from the cylinder head block. (Machine-translation by Google Translate, not legally binding)