GB579935A - Improvements in machine guns - Google Patents

Abstract

579,935. Machine guns. RICE, E. A. B., ROSE, A. G., CURTIS, S., NICHOLLS, K. H., and ROSE BROS. (GAINSBOROUGH), Ltd. Nov. 9, 1943, No. 18591. [Class 92 (ii)] A cocking mechanism for a machine gun comprises a cylinder 26, Fig. 3, housing a hydraulic ram 27 fitted with an arm 32 which is adapted to engage with the cocking stud 24 of the gun, a controlling valve 31 being provided to allow fluid under pressure to pass to one side of the ram or the other and means being provided for continuously urging the valve to the position in which it moves the ram to the inoperative position shown. The gun 11 shown is fitted in an aircraft turret as described in Specification 579,933, being mounted in a carrier member 12 which carries a bracket 28 on which cylinder 26 is mounted. A support 36 extends from bracket 28 and carries a casing 34 which has a guide slot for the cocking arm 32. Fluid under pressure is supplied to one or the other end of cylinder 26 by pipes 37, 38 leading to connections 39, 41, Fig. 5, of valve 31. The valve houses a plunger 54 which is urged upwardly by a spring 63 and has connections for fluid supply and exhaust pipes 68, 69. In normal position of the valve, fluid from pipe 68 passes through ports 71, 50 and 51 to reach annular port 45 which communicates with pipe 37, thus forcing ram 27 to the left, Fig. 3. When plunger 54 is depressed by hand, pipe 37 communicates with exhaust pipe 69 via ports 51 and 52, and annular port 46 which is connected to an annular port 74 communicating with pipe 69. At the same time, fluid under pressure passes from pipe 68 through ports 50 and 49 to annular port 44 communicating with pipe 38 and the ram is thus driven to the right, Fig. 3, to effect the cocking of the gun. The spring 63 restores the valve and thereby the ram elements to the inoperative position shown when the valve is released.