초록 ▼

Ceiling fan blades for low speed fan operation. The blades have a positive twist at the root motor portion of the blade and a slightly twisted rounded tip. The chord of the blades taper down from the root to the rounded tip, and have a tapered airfoil from the aft forward aft edge to the trailing ed

Ceiling fan blades for low speed fan operation. The blades have a positive twist at the root motor portion of the blade and a slightly twisted rounded tip. The chord of the blades taper down from the root to the rounded tip, and have a tapered airfoil from the aft forward aft edge to the trailing edge. The airfoil has a combination of a rounded leading edge with sharp trailing edge, and a square leading edge and rounded trailing edge. The blades can be twenty inches in length and twenty-six inches in length, and be used in ceiling fans having two, three, four or more blades in a ceiling mount. The ceiling fan blades are optimized to operate in ceiling fans running at low speed ranges of approximately 50 to approximately 200 revolutions per minute(rpm) with an enhanced axial airflow which provide substantial energy savings and increased air flow over conventional flat planar ceiling fan blades.

대표청구항 ▼

[ I claim:] [1.] A ceiling fan blade for low speed operation at approximately 50 to approximately 200 revolutions per minute(rpm) for use in overhead ceiling fan systems, the blade comprising:a positive twist adjacent to a rotor end of the blade, so that blade pitch increases from a tip end of the b

[ I claim:] [1.] A ceiling fan blade for low speed operation at approximately 50 to approximately 200 revolutions per minute(rpm) for use in overhead ceiling fan systems, the blade comprising:a positive twist adjacent to a rotor end of the blade, so that blade pitch increases from a tip end of the blade to the rotor end of the blade;an airfoil having a thicker portion at the rotor end tapering down to a thinner portion at the tip end, for providing high lift and low drag; anda blade chord having a wider portion from the rotor end tapering down to a narrower portion at the tip end, wherein the blade is operated in a ceiling fan running at low speed ranges of approximately 50 to approximately 200 revolutions per minute(rpm) for use with ceiling fan systems, and provides substantial energy savings and increased air flow over conventional ceiling blades. [15.] A method for operating an overhead ceiling fan system comprising the steps of:(a) rotating fan blades attached to a ceiling fan at a speed range of approximately 50 to approximately 200 revolutions per minute(rpm);(b) drawing a power supply of less than approximately 50 Watts; and(c) generating a downward airflow of up to approximately 6500 CFM from the rotating blades, wherein the ceiling fan system reduces power consumption and enhances axial air flow. The method for operating the overhead ceiling fan system of claim 15, wherein each of the fan blades include:a positive twist adjacent to a rotor end of the blade, so that blade pitch increases from a tip end of the blade to the rotor end of the blade;an airfoil having a thicker portion at the rotor end tapering down to a thinner portion at the tip end, for providing high lift and low drag; anda blade chord having a first width portion wider portion at the rotor end and a second width portion at the tip end, the first width portion being at least as wide as the second width portion at the tip end.