"220V Cooling Fan" is a DC voltage and electromagnetic induction, the electrical energy into mechanical rotation so as to drive the blades. DC fan wheel and blade design, with the wind and air pressure and DC fan blades collide compression capability is closely related to a serious point that affects the grade and quality of the entire DC fan, how to design efficient and simple process of "220V Cooling Fan" The main problem has been the researchers studied, the design efficiency impeller blades is the main way to solve this problem. DC fan blade balance between the performance of the entire DC fan, DC fan blade balance than being commonly used dynamic balance, it is the principle of adjustable vanes for DC fans and single-stage variable pitch type "220V Cooling Fan", Because only one level of the impeller, mass imbalance caused due to wear it all focused on the impeller, the balancing process is a single plane balancing process, namely static equilibrium process.