Principle: "Tiny Cooling Fan" works by energy conversion to achieve, namely: energy electromagnetic energy → → → kinetic energy to mechanical energy. The circuit principle is generally divided into a variety of forms, using different circuits, there will be differences in the performance of the fan. Axial "Tiny Cooling Fan" consists of: fan box, blades, bearings, PCB control circuit drive motor. Speed: speed refers to the speed of rotation of the fan, usually within one minute laps to measure the rotation, namely: rpm. Electromechanical speed winding turns, diameter, blade impeller diameter and bottom diameter, "Tiny Cooling Fan" leaf shape and the bearings and other factors, the speed increases, the air flow is increased accordingly.