Such conventional hydraulic "220V AC Cooling Fan" structure is very simple, the rotor and the stator to generate magnetic flux lines, and the direction perpendicular to the axis of the core extending the length, thereby driving rotation of the motor, but without using additional conditions to bear the entire the weight of the rotor blades, so the weight of the entire fan fell on all contact surfaces of shaft and bearing, the rotor will go around the stator offset any arc is inevitable, and therefore there will be an eccentric rotor rotates the motor Akira rotation rejection phenomenon, especially in the middle section of the magnetic flux lines of the most serious. But conventional hydraulic "220V AC Cooling Fan" is not nothing to consider, but also the use of the magnetic induction line design rotor and stator little suction caused by poor positioning, with the end of the shaft to the top brace to cause the rotor to straighten vacant, but still no action large, when the rotor during operation, or will produce biased rotation, forming a rotor droop emphasis, tend to rotate friction, especially in the now popular vertical chassis, "220V AC Cooling Fan" are playing straight fixed, long-term in this by running case, the original circle close to the true bearing diameter, will soon become oval, and the inner diameter of the surface will soon be worn, thus forming an irregular surface, the friction coefficient increased noise will therefore generate a .