Ceiling fan with high efficiency ceiling fan blades

Abstract

A ceiling fan including a motor having a rotatable rotor, a plurality of ceiling fans blades having a thickness, the blades connected to the rotor to rotate therewith and each of the ceiling fan blades comprising a thin edge along its leading edge that is thinner than the thickness of the ceiling fan blade to present less resistance and produce less turbulence and achieve high efficiencies.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] This invention relates to ceiling fans. More particularly, this invention relates to ceiling fan blades having a high-efficiency design. [0003] 2. Description of the Background Art [0004] Presently, there exist numerous types of ceiling fans designed to be suspended from a ceiling for circulating air flow within the room. Typically, ceiling fans comprise a plurality of ceiling fan blades which are operatively connected to an electric motor for rotating the fan blades to produce the desired air flow. The components of the ceiling fan, particularly the ceiling fan blades, are designed to optimize the amount of air flow being circulated per watt of energy consumed to thereby achieve high efficiencies. [0005] The fan blades constitute one component of a ceiling fan which is an important factor in achieving high efficiencies. Ceiling fan blades commonly include an elongated planar or curvilinear structure having a proxim...

AI Technical Summary

Benefits of technology

[0015] For the purpose of summarizing this invention, this invention comprises a ceiling fan having high efficiency fan blades. More particularly, several embodiments of the high efficiency fan blades of the invention each comprise a thin-edge configuration that effectively reduces thickness of the leading edge of prior art ceiling fan blades such that the thinner leading edge of the invention presents less resistance and produces less turbulence than thicker prior art fan blade edges. The thin-edge fan blades of the invention therefore result in high efficiencies.

[0017] Importantly, the thin leading edge of the invention is easily adapted to all types of ceiling fan blades that are currently being manufactured. For example, in the case of plastic fan blades, the thin edge design of the invention may be easily injection molded. In the case of plywood fan blades and MDF fan blades, the edge of the fan blade may be easily routed to the desired thin edge design and then sealed with a waterproof sealer painted onto the exposed edges.

[0018] In another embodiment of the high efficiency ceiling fan blades of the invention, the upper surface of the ceiling fan blades may comprise a generally apex configuration defined by two planar surfaces formed at an angle leading from the opposing thin leading edges across the width of the fan blade to form an apex along a center line of the fan blade. Importantly, the thickness of the fan blade at the thin leading edges comprises a reduced thickness which is equal to or appreciably greater than the minimum thickness mandated by applicable ceiling fan safety regulations. It is noted that the thin leading edge of this embodiment of the invention is contemplated to be principally formed by plastic injection molding or through carved fan blades due to the angles involved that could not typically be achieved through the use of laminated plywood or MDF. Indeed, this second embodiment is particularly desirable for implementation with decorative plywood or carved wood fan blades that would normally require significant sanding or carving to achieve the desired decorative designs. Moreover, the apex configuration provides strength along the longitudinal length of the fan blade thereby reducing the likelihood of drooping due to gravity over extended periods of non-use.

Problems solved by technology

Unfortunately, however, since plastic is typically heavier than plywood or MDF, plastic fan blades result in higher resistance to the electric motor thereby necessitating increased torque.

Unfortunately, however, the thick rounded edge of conventional fan blades produce a significant air resistance and turbulence as the ceiling fan blades are rotated through the air to cause the desired air flow.

The increased resistance and turbulence along the leading edge of the thick rounded leading edge of the fan blade appreciably reduces the efficiency of the ceiling fan.

In the case of the thicker plastic blades, even greater inefficiencies are often experienced.

Efforts to produce thinner blades that would correspondingly have thinner rounded edges, have met with little success since thinner blades do not have the necessary strength to function properly during continued use without droopage.

Moreover, prior art techniques for “beveling” the leading edge of a ceiling fan blade, such as taught by Taiwan Patent Application 79200819, filed Jan. 22, 1990, the disclosure of which is hereby incorporated by reference herein, have not met with any commercial success.

More particularly, beveling the leading edge of a ceiling fan blade such as taught by the Taiwanese patent application produces a relatively sharp knife edge that creates a hazardous condition in the event a person's hand or other object is moved into the path of the spinning fan blades.

Unfortunately, like planar fan blades, curvilinear fan blades still produce appreciable resistance and turbulence along their leading edges.

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