This device refers to the field of air flow circulation and more specifically to electric fans and even more specifically to the shape of the fan blade itself.
Traditional ceiling fans and other air circulating fans that are currently available have significant limitations with airflow being generally limited to the axial flow direction and confined to an air column that is only slightly larger than the diameter of the fan itself. This has led to multiple innovations over the years to tilt, rotate or oscillate the fan body itself in order to distribute the airflow more equitably around a given area. This current device is designed to provide improved airflow distribution utilizing the model of the current single axis fans such as, but not limited to, ceiling fans. The focus of this innovation is in the unique shape of the fan blade itself. Traditionally fans have blades that are designed for directional air flow. The blades of a traditional fan are mounted radially around a center axis and rotate around this axis forcing air in the direction of the axis itself. The radially mounted blade is pitched slightly in order to force air in an axial direction when rotated around this same axis. The pitch of the blade can create airflow in either axial direction depending on the direction of rotation. Historically, simple construction and manufacturing combined with generally adequate airflow have made the currently utilized pitched flat blade design the standard blade design for more than a century. Unfortunately, this blade design is somewhat limited to a very defined columnar shaped area of desired airflow. This proposed improvement in blade shape will allow for multi-directional airflow and much greater overall effectiveness of the fan without having to change other manufactured components.
Other fan blade systems have been proposed over the years and therefore to provide clear differentiation from each of these systems the disclosures of the associated US patents are included for reference herein. Oleson et al. describes an attachable airfoil winglet in U.S. Pat. No. 8,162,613, “ANGLED AIRFOIL EXTENSION FOR A FAN BLADE”, which is clearly designed as a separate attachment with a concave lower and a convex upper surface. Cooke, U.S. Pat. No. 4,662,823, “AIR TURBULENCE BLADES FOR CEILING FANS” and McChord, U.S. Pat. No. 871,729, “ELECTRIC FAN”, likewise describe blade tip attachments of different shapes in order to attempt better airflow, however both are still design limited to mechanically connected attachments with the associated problems in execution and esthetics. Another attachment based blade design by Aynsley, U.S. Pat. No. 7,252,478, “FAN BLADE MODIFICATIONS”, is an attached winglet designed to “improve aerodynamics of the fan blades” and does not affect radial airflow distribution. Bird, U.S. Pat. No. 6,719,533, “HIGH EFFICIENCY CEILING FAN”, describes blades that have concave top and bottom surfaces and are tapered, twisted, and have a gentle curve with a “continuously graduated dihedral”. This design is limited in that it only minimally affects the radial distribution of airflow.
While a variety of components and features have been incorporated into fans and fan systems, it is believed that no other fan blades described in prior art have made or used the invention described in the appended claims.
Currently available fans, more particularly ceiling fans, are designed to have radially distributed fan blades that are positioned horizontally radiating from a vertically mounted axis and create significant air flow in a space that is directly above or below the fan. These fans utilize standard flat blades that attach to a rotating hub at the axis. The blades are connected to the hub on the proximal end and this hub is rotated by an electric motor. Each blade is pitched in such a way as to force air downward (or upward if in reverse) when it is rotated around the axis by the force of the motor. This design creates a sort of wind column above or below the fan thus limiting the desired air circulation to almost exclusively the area directly under the fan leaving the rest of the room with minimal appreciable air circulation.
This proposed new blade shape is designed to not only force air downward as the other fans do, but also to force air movement more radially from the fan which will produce a much more widespread airflow pattern from the same fan. This newly designed fan blade is very similar to the traditional fan blades at the proximal most part of the blade where it configured to connect to the hub of the fan. The main difference is that the distal portion of the blade is angled upward in such a way as to allow the pitch of the blade to force air more radially outward in addition to the downward flow from the middle portion of the fan blade. The angled portion of the blade can have multiple embodiments depending on the amount of dihedral angle of the blade off of the horizontal plane, the angle of the of the distal portion with respect to the longitudinal axis of the proximal portion of the blade, the blade pitch, as well as the curvature of this same portion.
The following drawings serve to illustrate several aspects of the proposed invention, and together with the description serve to explain the principles of the invention; it being understood, however, that this invention is not limited to the precise depictions as illustrated. In the drawings, like reference numerals refer to like elements throughout all figures.
The following description of certain embodiments of the invention should not be used to limit the scope of the invention. It is possible that other features, aspects, versions, and advantages of the invention may become apparent to those skilled in the art based on the following description. Accordingly, the descriptions and drawings should serve as illustrative in nature and not at all restrictive.
Number | Name | Date | Kind |
---|---|---|---|
571500 | West | Nov 1896 | A |
871729 | McChord | Nov 1907 | A |
4640668 | Yang | Feb 1987 | A |
4693673 | Nee | Sep 1987 | A |
4730981 | Kawai | Mar 1988 | A |
D330077 | Davis | Oct 1992 | S |
5256037 | Chatelain | Oct 1993 | A |
D587799 | Oleson | Mar 2009 | S |
20080213097 | Oleson | Sep 2008 | A1 |
20090162197 | Klemo | Jun 2009 | A1 |