TWO-STAGE DRIVING FORCE TYPE ROCKET MOTOR

PURPOSE:To prevent the breakage of a nozzle due to a cover body by pivotally installing the basic part of the cover body onto a cylindrical body and fixing the cover body onto the cylindrical body by a fixing means which releases the fixing force by the combustion pressure in the second combustion chamber. CONSTITUTION:When the first propellant 21 is combusted by the first ignitor 25, and an elevation driving force is obtained, the elevation is continued to an aimed height. When the combustion of the propellant 21 is completed, the second propellant 22 is ignited and combusted by the second ignitor after the lapse of a prescribed time after the completion of the first propellant 21. The combustion pressure accompaied with this combustion acts onto a fixed screw 30 through a cover body 28, and when this pressure increases over the cut load of the fixed screw 30. The fixed screw 30 is cut. Therefore, a communication hole 27 is opened by turning the cover body 28 downward around the pivotal shafts 28 and 29, and the combustion gas in the second combustion chamber 24 is jetted outside through the first combustion chamber 19 and a nozzle. A rocket can obtain the elevation driving force, accompanied with this injection.