GB248416A - Improvements in or relating to depth charges and like submarine explosive bodies - Google Patents

Abstract

248,416. Vickers, Ltd., and Pratt, H. B. Oct. 3, 1924. Projectile fuzes. - Relates to depth charges provided with a pistol set in action by the compression of air by a piston under hydrostatic pressure, and consists mainly in the provision of means for varying the volume of air trapped for compression according to the depth at which it is desired the pistol shall function. As shown in Fig. 1, the depth charge C has a central axial tube A containing at the bottom end a primer D and fitted at the top with a casing F, which is divided into four chambers f<1>, Fig. 3, and carries the detonator e<1> and the spring striker e<4>. A valve H rotatably adjusted by a head e<6> determines the number of chambers f<1> put in communication through ports h in the valve with the space G between the primer D and the detonator e'; this setting is performed over a clicking detent e<14> and is indicated by a pointer e<12>. Before the depth charge is dropped, a safety pin d<3> is removed from a stem d projecting out from the primer D. Hydrostatic pressure can then force the primer D up the tube A, compressing the air in the space G and in the chambers f<1> in communication therewith. A rubber ring d<4> seals the joint between the primer D and the tube A. At a depth depending upon the volume of air above the primer, the primer reaches the detonator e<1>, which enters a recess d<5> in the primer. Further movement of the primer lifts a sleeve e<3> and the striker e<4> against a spring e<7> until balls e<8> escape over a shoulder e'‹, when the striker is released and fires the detonator. In a modification, the additional air chambers are contained in a tubular casing fitted into the top end of the tube A; and interengaging projections are provided between the valve stem and the casing, which lock the striker at safe when the valve stem is set to a given position indicated as safe by the pointer thereon.