Abstract: A quick pressing firing mechanism of the pneumatic fire-extinguishing cannon is studied,in which an associated tube is used for servo launch, solving the problem of that the launch gas pressure in the bore is required transiently to achieve the pressure in the gas chamber while launching. A dynamic model of firing process and a parameter model of gas in the bore are established, and a motion equation of projectile during firing is given. The variation characteristics of gas parameters in the bore are obtained by the simulation analysis of firing process in MATLAB environment. The effect of different firing angles on the firing characteristics is studied, and the optimal firing angle is obtained. The impact process of the firing mechanism is verified by using the software. The result shows that the firing mechanism with associated tube can be used effectively to solve the problem of high-pressure gas reaching the total launching pressure in the chamber transiently.

Key words: ordnance science and technology, fire-extinguishing cannon, firing mechanism, pneumatics, dynamics