US Patent 7688566 Electric firing device for fireworks

An electric firing device for fireworks comprising a circuit board (7) fixed inside of a mounting clip (8); a firing slot (6) set in the front of the circuit board (7); a resistance wire (5) welded on the circuit board (7) together with a conductive wire pair (9) and straddled on said U shaped firing slot (6); a firework lead wire slot (4) set on the mounting clip (8); and a lead wire propulsion stop plate (2) set on a top cover (1) and engaged with the mounting clip (8). The resistance wire (5) is made of a resistance wire with good electricity to heat conversion capability (such as tungsten wire, nichrome wire, constantan wire, and so on) and spirally-wound.