Patent GB-191007637-A (GB)
Title: Improvements in or relating to Breech Mechanism for Guns.
Inventor: BRIGGS OLIVER HERRICK
IPC: F41A17/48
Filed: 1910-03-29
Granted: 1910-12-22
Abstract: 7637. Briggs, O. H. March 29 Ordnance breech mechanisna.- Relates to firing-mechanism of the kind that is carried by a sliding member and can be operated mechanically or electrically, and consists in improvements in construction and in the provision of means to prevent accidental discharge when the breech is not locked. The breech-screw 16, Fig. 2, carrier 18 and operating-mechanism, obturator stem 27, primer 29, and extractor 30 are all of known construction. A support 31, shown separately in Fig. 3, is mounted on the carrier 18 and has a dovetailed slideway 32 to receive a slide 36, Fig. 4, and also bearing-lugs 33, 34 to receive the shaft 35 in such a manner that it can rotate but not slide therein. The percussion hammer 38 is slidably mounted on the shaft 35 between lugs 37 on the slide 36, which also loosely embrace the shaft. The firing-pin 39 is mounted in an insulating - sleeve 40 and is normally pressed against the primer by a light spring 40<1>. The head 41 of the firing - pin is connected to a flexible electric connexion, thus forming one terminal of the electric firing-circuit, the other terminal being connected to the gun or mounting in known manner. A slotted link 43 engages a recess 46 in the slide 36, and is removably connected thereto by the toe 47 of a spring catch 48 pivoted to the slide. The forked end of the link engages a pin 51 on an arm 52 rigidly secured to the shaft 21 of the breech actuating-lever. A collar 53 is rigidly secured to the shaft 35 and a second collar 54 is loosely mounted thereon, both collars having ratchet teeth to facilitate adjustment of the spring 56, which operates the shaft 35 for percussion firing. A toe 58 on the collar 53 engages a toe 60, Fig. 6, on a cocking-lever 59, which is operated by means of a cam 65 on the breech-screw 16 to cock the hammer as the breech screw is locked. A projection 68 on a collar 67 on the shaft 60<1> engages a head 63 on the spindle 62 which carries the toe 60, and, by means of an arm 69 and a lever 70 pivoted on a shaft 71, the spindle 62 is moved inwards to release the hammer 38 for firing. The arm 72 is adapted to receive a lanyard rod or other connexion from the firing-key. A safety-device consists of an arm 73, Fig. 7, on the shaft 60<1> adapted to engage a cam 74 on the breechscrew and to come opposite to a recess when the breech-screw is fully locked. In operation, the breech is unlocked and opened by a single movement of the operating-lever, and the slide 36, hammer, and firing-pin, are at the same time moved out of line with the primer, the firing-pin then bearing upon the insulation 42<1>. In closing and locking the breech, the parts return to their normal positions, and the hammer is cocked. In one modified arrangement, the firing-pin is located below the hammer. In a second modification, for use with guns firing fixed ammunition, the firing- pin extends through the carrier arm and breechscrew, from which it is insulated, the spring controlling the firing-pin being carried in the breechscrew. The hammer and its actuating-mechanism are arranged as described above.