Two Ball Rotors Safety System Design Of Small Caliber Fuze

The delay arming time of most commissioned national small caliber fuze can not satisfy the delay arming requirement. A modern small caliber fuze should posses delay arming, redundancy safety, high sensitivity, large striking angle firing, auto-destruct and rain insensitive properties. This made small caliber fuze design difficult due to the small space, especially for flameproof and delay arming mechanism design. Thereby the high property small caliber fuze design is still difficult now.Ball rotor mechanism was simple, small, low cast and high reliable. Its delay arming distance only was only some meters which can not fit for the small caliber fuze delay arming requirement.Two ball rotors mechanism both as flameproof and delay arming device was designed according with small caliber base type fuze. High property small caliber base fuze scheme was advanced combined with the design scheme of firing device, auto-destruct mechanism and explosive sequence.Based on the ball rotor motion theory, spherical shell dynamic model was established in the conditions of misalignment among mass center, centre of figure and projectile spinning axis. The force of spherical shell, ball rotor and centrifugal pin was analyzed. Motion differential equations of was established.Spherical shell motion simulation was made applied with ANSYS/LS-DYNA. According to the simulation results, centrifugal pin and spherical shell structure was modified. Strength and strain analysis of spherical shell groove was done. The simulation results proved that two ball rotors mechanism was feasible for prolonging delay arming time.