Central shaft for winding and coating star-hole propellant grain

The invention provides a central shaft for winding and coating a star-hole propellant grain. The central shaft comprises a main shaft, star teeth and connecting screws, wherein the plurality of star teeth are connected and fixed in a plurality of main shaft grooves in the main shaft through the connecting screws. According to the central shaft, the assembly gap size, the number and the length of the star teeth are considered, so that smooth assembly and demolding of the central shaft and the propellant grain are guaranteed; the contact area between the star tooth profile and the propellant star hole inner profile is the largest in the winding power transmission process, and star teeth are prevented from damaging the propellant powder surface while the winding power transmission process isachieved. A material combination of high-strength steel and brass is adopted, the rigidity of the high-strength steel is used for guaranteeing the strength requirement of the main shaft, and the safety characteristic of the b