Dynamics of Pin Pallet Runaway Escapement
ARMY ARMAMENT RESEARCH AND DEVELOPMENT CENTER DOVER NJ
Pagination or Media Count:
This paper reports on the development of a simulation of a constant input torque pin pallet runaway escapement. The resulting program provides a basic tool for the analysis and synthesis of various safing and arming devices. The dynamics of the regimes of motion of the escapement were formulated. Coupled motion, with continuous contact between escape wheel tooth face and pallet pin, impact of the pin on the tooth face and uncoupled, or free, motion of these mechanism components were considered. The associated regime equations apply to entrance as well as exit conditions. Sensing expressions for the determination of the instantaneous positions of the pallet pin and the escape wheel form the basis of the controls of the computer program. The sensing equations indicate the presence of such pathological conditions as tip or back face contact. The simulation was applied to the timing mechanism of the M525 fuze. The influence of changes in such parameters as escape wheel input torque, pallet moment of inertia, center distance, pallet radius, etc., on the mechanism delay time were explored in detail by appropriate computer runs. The results, compare favorably with existing experimental data.
- Ammunition and Explosives