GB101716A - Improvements in or relating to the Breech Mechanism of Ordnance. - Google Patents

Abstract

101,716. Asbury, D. F. Oct. 4, 1915, [Convention date]. Ordnance breech mechanism. - Relates to poweroperated screw breech mechanism of the kind having a brake device comprising a reciprocating-element which moves constantly with the breech-actuating motor to control the movements of the breech mechanism, and is par ticularly applicable to the mechanism described in Specification 16406/15. According to the present invention, the breech-actuating motor comprises a reciprocatory-element which is rigidly connected to and moves with the reciprocatorv-element of the brake device during its entire stroke. Fig. 1 shows a rear view of the breech with the screw in the closed and locked position. The breech is actuated by an air-pressure cylinder-and-piston device, the cylinder 33 of which is hinged to the gun, the piston 48 being, by means of its rod 34, connected to an arm 25 fixed to the upper end of a shaft 14. This shaft rotates in the breech-screw carrier C and, through the medium of a crank 15, pin 16, and sliding block 20, moves a link to rotate the breech-screw for locking and unlocking. When the breech-screw is rotated for unlocking, camdevices M, N initiate the opening movement of the carrier, and the further movement of the piston 48 then causes the carrier to swing open. The hydraulic brake device for controlling the movements of the breech mechanism has its cylinder 34 mounted within the pneumatic cylinder 33 so as to form a guide for the piston-rod 46, to which are connected the brake piston and rod 52, 51. The brake cylinder is kept full of liquid by providing a reservoir 36 which communicates with the brake by a ball valve 40. The reservoir 36 is filled through an opening provided with a screwed plug 42 having a central portion 43 forming an air-pocket, the end portion of the plug being formed with openings 44, 45. Leakage of liquid is thereby prevented, and atmospheric pressure is maintained above the surface of the liquid in the reservoir. During the breech-opening movement, the liquid flows freely through a by-pass 54 and ball valve 55 until the by-pass moves beyond a flange 56, when throttling occurs between the piston 52 and a reduced portion of the cylinder to bring the carrier to rest gently in the open position. The space 58 being in communication with the low-pressure side of the piston, the packing 53, where the piston-rod leaves the cylinder, is not subjected to the braking-pressure. When the breech-closing movement occurs, the valve 55 closes, and a variable braking occurs between the piston 52 and portions of the cylinder 34 of different diameters and also by liquid passing through a passage 38 into the reservoir.