GB789479A - Control device for the percussion pin of a projectile fuze - Google Patents

Abstract

789,479. Ammunition fuzes. VOLAND, A. Nov. 25 1955 [Dec. 6, 1954], No. 33918/55. Class 9(1) A percussion fuze for rotated projectiles having a spring-stressed firing pin is provided with self-destruction means comprising a dash-pot in which a spring-loaded piston moves against the damping action of a mass of silicone grease containing. Si (CH 3 ) 2 groups, the piston being held against displacement by means released by centrifugal force. The fuze has a body 1 with a screw-threaded shank 5 for connection to a projectile and an axially slidable firing pin 3 extending through a channel in a base plug 5. The head of the pin 3 bears against an elastic disc 9 housed in a member 10 within the fuze nose. Held in position by the plug 5 is a cylinder 33 housing a spring-stressed piston 34 surrounding a cylinder 36 containing a piston 37 which is held against forward movement by three spaced balls 40 bearing against the pin 3 and prevented from escaping by the piston 34. A slotted plunger 27 locking the firing pin 3 is held in position by a mass 31 of silicone grease similar to the mass 42 in the space between cylinders 33 and 36. On launching the projectile due to centrifugal force the plunger 27 forces the mass 31 through a calibrated hole 30 and as the mass escapes the plunger moves outwards. thereby releasing the piston 34. Spring 35 thereupon forces the piston 34 forwards so driving the mass 42 through a calibrated hole 43. The hole is so calibrated and the mass 42 and spring 38 so chosen that the piston 34 uncovers the balls 40 when self-destruction is to take place. As soon as the plunger 27 frees the pin 3 the fuze is armed ready for actuation on impact. If impact does not occur within a given time, when the balls 40 are freed they move outwards due to centrifugal force and release the piston 37 which is then driven by its spring against a shoulder on the pin 3 to force the pin 3 on to the detonator (not shown). In Fig. 2 a single dash-pot provides for muzzle safety and self-destruction. A piston 55 holding weights 53 in engagement with the firing pin is locked bv a bolt 57 secured by a split ring 58. After firing. when acceleration of the projectile ceases, the ring 58 opens under centrifugal force and releases the bolt 57 and the piston 55 is then freer and moves forwards forcing the dash-pot material 68 through openings 67, 69. As soon as the piston moves beyond the opening 67, the bolt 62 locking the,firing pin is released and the material 68 can only escape through openings 69. The fuze is then armed for ignition on impact. If impact does not occur within a given time, the weights 53 are freed and self-destruction takes place.