Outer-rotor fans. Outer rotor fan

Features, structures and some products of outer-rotor fans were outlined. The outer-rotor fan is composed of an inner stator with a primary coil, an outer cage rotor and a propeller type impeller attached directly to the periphery of the rotor, and is featured by the axial construction thinner by 40% than previous ones. Stable operation was obtained in the whole air capacity range by expanding the blade area of the impeller, and the air capacity larger by 15% and energy consumption smaller by 16% than those of previous ones were achieved at the same impeller diameter. The low-temperature/water-proof type fan for unit coolers could be used at {minus}50-+30{degree}C, and the high-temperature type one for environmental test apparatus at {minus}30-+80{degree}C by suppressing temperature rise with the special coil and bearing. The reliable medium-pressure low-noise type one for information processing equipment was also developed by adopting the special casing and impeller less in break away on blade surfaces at medium pressure. 1 ref., 4 figs., 2 tabs.