Patent GB-494302-A (GB)
Title: Improvements in or relating to percussion fuzes
IPC: F42C15/26
Filed: 1937-04-21
Abstract: 494,302. Projectile fuzes. VICKERSARMSTRONGS, Ltd., and TAYLOR, H. G. W. April 31, 1937, No. 11431. [Class 9 (i)] Relates to a percussion fuze for projectiles in which the striker is maintained in an unarmed position by means of centrifugal members which are retained in their operative position until after discharge of the projectile by a retaining element. According to the invention, a safety ring is provided which positively prevents displacement of the retaining element prior to discharge of the projectile, said ring being adapted to set back on discharge in order to free the retaining element which is adapted thereafter on retardation of the projectile to move forwardly independently of the ring and solely due to its momentum and without the aid of a spring or ingress of external air in order to free the centrifugal members and allow arming of the fuze. As shown in Fig. 1, a housing 11, formed with a chamber 12 adapted to receive the flash composition, is retained in position within the fuze body 10 by means of the normal gaine 13. The inner end of the striker 14 projects into a channel 15 in the housing 11 communicating with the chamber 12, the outer end of the striker being protected by a cap 16. The striker is supported in its unarmed position by a plurality of centrifugal members, such as balls 17, disposed between the forward end of housing 11 and a flange 18 on the striker, the balls being retained in their operative position by a creep ring 19 supported on the forward end of the housing 11. The creep ring is locked in its operative position by means of a setback ferrule 20 formed at its front end with an inwardly directed conical portion or with projections adapted to co-operate with the flared rearward end of the ring 19. On discharge of the projectile, the ferrule 20 sets back and the ring 19 is freed. This ring, however, remains in its operative position until retardation of the projectile takes place whereupon it moves forward due to its momentum and frees the balls 17 which latter will then be flung outwardly under centrifugal force and thus free the striker 14 which is thereby armed. According to the modification, Fig. 3, a separate creep ring is dispensed with, the flange 18 on the striker being formed around its periphery with a depending flange 24 adapted when the striker is in its normal position to prevent the balls from moving outwardly. The striker is locked in its safety position by the inwardly directed conical portion or projections on the ferrule 20 co-operating with a conical portion 25 on the flange 18. With this construction, on the setback of the ferrule 20, the striker is freed but remains in the safety position until retardation of the projectile takes place whereupon it moves forwardly and allows the balls 17 to escape. The housing 11 is formed with a recessed portion 27 adapted to receive the flange 24 when the striker moves inwardly on impact. If desired, the ferrule 20 may be arranged to co-operate with an outwardly flared portion at the rear of the flange 24. In order to assist the forward movement of the ring 19, Fig. 1, or of the striker 14, Fig. 3, these members may be formed with a conical or like surface on which the balls 17 are adapted to act or the forward end of the housing 11 may be formed with a coned or similar surface 23 as shown in Fig. 3. The Provisional Specification describes further constructions in which the safety ring is arranged in front of the creep ring or on the front end of the striker, the arrangement being such that, on discharge of the projectile, the ring sets back and interengages with the creep ring or striker so that, on retardation of the projectile, both the safety ring and the creep ring or striker move forwards and thus release the centrifugal members.