A REVIEW OF THREE PATENTS RELATING TO THE DEVELOPMENT OF NOVEL INERTIA-DRIVEN MECHANISMS FOR IGNITERS ON-BOARD GUN-FIRED MUNITIONS

摘要

This is a review of a series of three patents issued for inertia igniters: devices which are generally used onboard gun-fired munitions to provide pyrotechnic initiation of a thermal battery. The igniters use the overwhelming firing acceleration to drive various mechanism components which provide event-sensing and a time time-delay in addition to the mechanical striking which ignites the pyrotechnic element of the igniter. The embodiments in the three patents progresses from a novel approach to achieve greater axial compactness while maintaining equivalent performance to a benchmark design, to a two-stage design which expands the range of performance of the event-sensing and time-delay characteristics of the devices, and finally to several novel approaches for producing arbitrarily long delays and the sensing of large impulses in highly compact multi-stage inertia-driven devices. The expansion of the range of operation of such devices is particularly important because prior to these innovative approaches, long delays or the practical measurement of large impulses required electronic methods and an additional tier of electrical power in addition to the thermal battery which is to be initiated.