Patent GB-303418-A (GB)
Title: Highly sensitive head impact fuse with automatic delay ignition for projectiles
IPC: F42C15/24
Filed: 1929-01-02
Abstract: 303,418. Wieser, K., and Wieser, H. Jan. 2, 1928, [Convention date]. Projectile fuzes.-Relates to direct-action percussion fuzes of the kind in which the striker d, Fig. 1, is mounted in a sleeve b which, when displaced on impact, introduces a delay in! the action of the fuze. According to the invention, the sleeve b is held in its normal position by a spring c and is covered by a brass cap g which must be crushed on impact before the sleeve b can be displaced. The percussion cap e is mounted in the fuze body and is separated from the striker by a centrifugal safety device f. The sleeve b bears on a pin k, which rests on the bevelled end of a transverse bolt provided with a clear port l and another port m containing a delay-action composition, the clear port being normally in line with the percussion cap. On discharge, the sleeve b sets back and the pin k wedges the bolt h against a spring i, bringing the delay-action composition m into line with the percussion cap. Any accidental firing of the cap at this moment cannot therefore cause damage by premature explosion of the projectile in the gun barrel. During flight, the sleeve b and bolt h return to the normal position shown, and the centrifugal safety f opens out and leaves the percussion cap and striker free to approach each other. On impact with a soft target, the target substance penetrates a hole g<1> in the cap g and drives the striker against the percussion cap, the flash from which passes undelayed through the port l. A glancing impact on a hardl target causes the percussion cap to move forward by virtue of its momentum, and explosion again occurs without delay. But on direct impact with a hard target, the brass cap g is crushed and the sleeve b is driven in and by means of the pin k wedges the bolt h aside, bringing the passage m in line with the percussion cap, and this delays the explosion. The Specification as open to inspection under Sect. 91 (3) (a) describes other constructions of fuzes. In one construction, the sleeve b rests not on a spring c but on a small collapsable tube, the striker d is locked to the sleeve b and to the fuze body by transverse bolts confined by a coiled lead tape, which unwinds by centrifugal force during flight, and the percussion cap is fixed to the fuze body. In another construction, Figs. 6 (Cancelled) and 9 (Cancelled;, a screw p is fitted transversely in the fuze body and provided with an eccentric pin p<1> in engagement with a longitudinal slot b<2> in the sleeve b, and the sleeve is formed with a cam b<4> between a slot b<3> and a shoulder b<5>, either of which three parts b<3>, b<4>, b<5> can be set opposite the pin k according to the angular adjustment of the screw p. When the pin k is opposite the cam b<4>, the delay-action is automatic, as for Fig. 1; when the pin k is opposite the shoulder b<5>, the delayaction is all the time in operation ; and when the pin k is opposite the slot b<3>, the action is always instantaneous. This subject-matter does not appear in the Specification as accepted.