SAFETY DEVICE Russian patent published in 2000 - IPC

FIELD: pyrotechnics. SUBSTANCE: safety device is designed to prevent unauthorized operation of devices containing pyrotechnic charges in case of excessive temperature rise, for example, under conditions of fire. Safety device has a body and charges. Ignition temperature of igniting charge is lower than that of main charge. The device also includes fire duct with overlapped zone and switching element consisting of at least two parts. Switching element is mounted in fire duct for motion in assembly and in parts and fixed in body by means of thermosensitive material and its releasing temperature is below ignition temperature of igniting charge. Prior to device operation, main charge is isolated pneumatically from igniting charge by switching element parts. When assembled, switching element is made as valve gate, and it is fixed in body over peripheral part on side of igniting charge. Overlapped zone of fire duct is formed as a seat. Connection is provided between parts of switching element. Strength of the connection is below that of peripheral part fixing. Central part is manufactured so that when its connection to peripheral part is destroyed, it moves till it thrusts upon seat without fire-duct overlapping. The device makes it possible to extend range of permissible constructional parameters and to simplify manufacturing technology. EFFECT: enhanced reliability. 5 cl, 3 dwg