GB667639A - Improvements in and relating to the obturating of the breeches of guns - Google Patents

Abstract

667,639. Ordnance. SOC. DES FORGES ET ATELIERS DU CREUSOT. March 13, 1950. No. 6291/50. Class 92 (ii). An obturator for a gun is in the form of a screen which is in contact with the rear face of the inner tube 1 of the barrel and is movable into and out of the obturating position while remaining in the same plane. The obturator shown consists of two plates 9, 10, pivoted respectively at 11, 12, and secured together at 9b, 9c, so that they move inwards and outwards in unison. A rod 16 connected to the plate 10 is linked to a shaft 20 which is surrounded by a torsion spring tending so to rotate the shaft as to cause' the plates to move to the breechclosed position. The meeting edges of the plates may have co-operating tongues and grooves to ensure a gas-tight seal. The opening of the breech has no effect on the plates, but when a loading arm 7, Fig. 3, is brought to the loading position it engages and moves a lug 29 on a shaft 26 linked to the shaft 20, and the latter is moved to open the plates. The plates are held in the open position by a latch 30, which engages the inner edge of the plate 9. However, the latch is pressed forwards to an inoperative position by the rim of the round when the round is loaded into the chamber, and when the loading arm is moved away the plates move slightly inwards to bear against the cartridge rim, such movement preventing the catch from re-engaging the edge of the plate 9.