Patent GB-191127938-A (GB)
Title: Improvements in or relating to the Breech Actuating and Loading Apparatus of Heavy Guns.
Inventor: DAWSON ARTHUR TREVOR
IPC: F41A5/32
Filed: 1911-12-12
Granted: 1913-03-12
Abstract: 27,938. Dawson, Sir A. T., and Horne, J. Dec. 12. [Addition to 22,043/10.]. Ordnance breech mechanism. - Consists in a modified construction of automatic control devices for an hydraulically-operated breech mechanism, of the kind described in the parent Specification. The improved mechanism comprises two co-axial rotary control valves, one of which may form a seat for the other. Of these valves, which are shown in section in Fig. 4, one, D, is rotated by a pinion D' gearing with a rack D<2> connected by a rod D<Î>, Fig. 1, to one arm of a bell-crank C<Î>, pivoted to the slide-frame C, the other arm of which bell-crank engages with a cam-groove B<Î> in the recoiling gun-cradle B. The other valve E is controlled at various times (1) by the first valve, (2) by the rocking-plate G, Fig. 3, co-axial with the valves and driven by the breech-actuating motor C<2> through a worm-gear G‹, and (3) by an arm C<3> connected by a rod C<1Î> to an arm c'X that moves with the loading-tray C<1>. Two of the ports of the valve D are arranged so that they admit pressure to the motor C<2>, to open and close the breech respectively. The valve E, by its movement, connects these ports to pressure and exhaust in turn. When the gun recoils, the bell-crank C<Î> rocks the valve D relatively to the valve E until the breech-closing ports are open to pressure. The valve E is then carried round by the valve D into a position in which, as the recoil stroke ends, it becomes engaged with the rocking-plate G by means of a spring bolt E<2> mounted on a plate E' that is rotated by the valve E through its square stem e', and which bolt E<2> engages a recess g<Î> in the plate G. During the run-out of the gun, the valve D is rocked back again by the bell-crank C<Î>, and, moving relatively to the valve E, opens the breech-opening ports to pressure. The motor C<2> is thus started, and, through the worm-gear G<0>, drives the plate G, and with it the valve E, in the same direction as the valve D. The motion continues until the gun has come to rest in the case of the valve D, and, in the case of the valve E, until that valve has resumed the cut-off position relatively to the valve D. If the gun has fully run-out, the breech will be completely opened, but if the run - out is incomplete, the valve E is moved until it overtakes the valve D and cuts off the pressure with the breech incompletely opened. When the loading-tray C' is raised, it rocks the arm C<3> rearwards, and enables the spring bolt c<3> carried thereby to project itself in such a manner that, when the tray C' is lowered and the arm C' moves forward again, the bolt acts upon a bellcrank lever e<2ÎÎ>, E<2Î> and releases the spring bolt E<2> by which the valve E is still locked to the plate G. The arm C<3> then moves the valve E relatively to the valve D and to the plate G, and opens the breech-closing ports to pressure. The motor C<2> then drives the plate G in the reverse direction, until a projection g<1> thereon rocks the valve E back into the cut-off position. At the same time, a cam G<1> on the plate G retracts the spring bolt c<3>, and the parts are thus all brought to their original positions.