Inertial igniters with safety pin for initiation with low setback acceleration

Abstract

Inertial igniters for initiating a thermal battery and methods of preventing initiation of an inertial igniter are provided. The method including: biasing a mass element from a base element with a spring element connecting the mass element and the spring element; and removably disposing a safety member between the mass element and the base element to prevent relative movement between the mass element and base element to prevent accidental initiation of the inertial igniter. The method can further comprise removing the safety member prior to subjecting the inertial igniter to all-fire conditions.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims benefit to U.S. Provisional Application No. 61 / 184,787 filed on Jun. 6, 2009, the entire contents of which is incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates generally to inertial igniters for thermal batteries or other pyrotechnic type initiated devices for munitions, such as rockets, with low setback accelerations and equipped with safety pins.[0004]2. Prior Art[0005]Thermal batteries represent a class of reserve batteries that operate at high temperatures. Unlike liquid reserve batteries, in thermal batteries the electrolyte is already in the cells and therefore does not require a distribution mechanism such as spinning. The electrolyte is dry, solid and non-conductive, thereby leaving the battery in a non-operational and inert condition. These batteries incorporate pyrotechnic heat sources to melt the electrolyte just prior to use in...

AI Technical Summary

Benefits of technology

[0009]Accordingly, an inertial igniter is provided. The inertial igniter comprising: a mass element; a base element; a spring element connecting the mass element and the base element; and a safety member removably disposed between the mass element and the base element for preventing relative movement between mass element and base element to prevent accidental initiation of the inertial igniter.

[0019]Also provided is a method of preventing initiation of an inertial igniter. The method comprising: biasing a mass element from a base element with a spring element connecting the mass element and the spring element; and removably disposing a safety member between the mass element and the base element to prevent relative movement between the mass element and base element to prevent accidental initiation of the inertial igniter.

Problems solved by technology

The electrolyte is dry, solid and non-conductive, thereby leaving the battery in a non-operational and inert condition.

The process of manufacturing thermal batteries is highly labor intensive and requires relatively expensive facilities.

Fabrication usually involves costly batch processes, including pressing electrodes and electrolytes into rigid wafers, and assembling batteries by hand.

Such electrical igniters, however, require electrical energy, thereby requiring an onboard battery or other power sources with related shelf life and / or complexity and volume requirements to operate and initiate the thermal battery.

The mechanism or circuitry for distinguishing an accidental drop from an all-fire condition can be complicated and expensive.

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