GB583472A - An improved clockwork fuze for projectiles - Google Patents

Abstract

583,472. Projectile fuzes. SCHWEIZER, P. April 2, 1943, No. 5345. [Class 9 (i)] Relates to clockwork fuzes of the kind having two oppositely-rotating members driven at different speeds and having gapped peripheries, the gaps of which are relatively displaced in the setting of the fuze and permit the release of the striker by a centrifugally-operated bolt only when they reach coincidence during the running-down of the clockwork. According to the invention, a spring-urged lever which locks the striker-release bolt is itself locked by a second or safety lever which is held in locking position by a spring until the fuze is set, and is released by centrifugal force, both levers having projections which coact with the gaps in the two rotating members. The axial striker 3 is held by a centrifugally-operated bolt 14, itself locked by the entry of the semicircular end 35 of a rock-shaft 12 into a notch 13 in the bolt. A lever 16, controlled by a spring 17, is mounted in the other end of the shaft 12. This lever is held in the " safe " position shown in Fig. 3 by a second lever 22, rockable' on a pivot 23 by centrifugal force, against the pull of a spring 24, to release the lever 16. The latter has upwardly and downwardly extending projections 18, Fig. 8, and the lever 22 has similar projections 27. The levers lie between two rotatable members 5, 11, the former being a disc driven by the clockwork and the latter a ring driven at reduced speed and in the opposite direction by gearing 6, 7, 9, 10, the pinion 6 being integral with disc 5. The disc has a flange 6a in which a gap between the ends 25, 26 and the ring 11 has a gap between the ends 30, 31. In the zero or safe position, the two gaps are in register and projection 27 on lever 22 lies against the end 25 of flange 5a. 'When the fuze is being set, the gaps move apart, the disc 5 being rotated clockwise (Fig. 3) and the ring in reverse direction, until a set position, such as that shown in Fig. 6, is reached. In these rotations, the bevelled flange-end 26 engages the lever projection 27 and moves the lever outwards, so as to disengage the lever 16 which is, however, held against outwards movement by the engagement between the ring 11 and the lever projection 18. When the shell is fired, the clockwork.is started in known manner, and the discs are rotated back until the gaps return to registering positions. Centrifugal force maintains the lever 22 in its outward position, but the lever 16 is moved through the gaps by centrifugal force aided by the spring 17 ; the detent 35 is thereby moved out of the notch 13 in the centrifugal bolt 14, which is then moved outwardly to release the striker 3.