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Our customer is an Indian multinational engineering company with interests in automobile, power, oil & gas, aerospace, construction etc. They are engaged with development of mechanical timers which is a critical safety component for arming of defense devices. Due to severe restriction on quantity of metal content in such devices, it is necessary that the timer is made up of plastic, but still be robust enough to withstand shock, vibrations and drop. The customer sought an independent design review that employed numerical analysis to confirm the reliability of their design.

Zeus Numerix developed a mathematical model for timer that simulated the escapement mechanism and calculated torque balance between gear elements to estimate time of operation. It was followed by Finite Element based analysis for robustness of timer housing and stress concentration on gear teeth. Finally, a sensitivity and parametric analysis were conducted to identify critical design parameters effecting performance and robustness of the timer design.

Left: Pallet-Escape Wheel mechanism, Right: Stress distribution on gear teeth

Left: Pallet-Escape Wheel mechanism, Right: Stress distribution on gear teeth

Our customer was delivered with a detailed design review report suitably supported by mathematical calculations and simulation results. The outcome of the study were incorporated into a design document and submitted to end client. This study helped our customer to obtain a go-ahead for bulk fabrication of the timer devices.