The present invention relates to the field of ceiling fans. The present invention in particular relates to new blade with downward winglet for Ceiling Fan.
BACKGROUND OF THE INVENTION
Ceiling fans powered by electric motors have been used for years in circulating air. They typically have a motor within a housing mounted to a downrod that rotates a set of fan blades about the axis of the downrod. Their blades have traditionally been flat and oriented at an incline or pitch to present an angle of attack to the air mass in which they rotate. This causes air to be driven downwardly.
When a fan blade that extends generally radially from its axis of rotation is rotated, its tip end travels in a far longer path of travel than does its root end for any given time. Thus its tip end travels much faster than its root end. To balance the load of wind resistance along the blades, and the air flow generated by their movement, fan blades have been designed with an angle of attack that diminishes towards the tip. This design feature is also conventional in the design of other rotating blades such as marine propellers and aircraft propellers.
Furthermore, many of the flat ceiling fan blades have problems such as poor performance at high speeds, wobbling, and excessive noise that is noticeable to persons in the vicinity of the fan blades.
Some alternative blade shapes have been proposed for other types of fans. U.S. Pat. No. 1,506,937 requires that their blades have root "lips 26" FIG. 1 that overlap one another, and would not be practical or useable for three or more fan blade operation for a ceiling fan.

U.S. Pat. No. 2,682,925 describes "fan blades . . . particularly adapted to fan blades on top of cooling towers such for example as are used in oil refineries and in other industries . . . ", column 1, lines 1-5, and does not describe any use for ceiling fan applications.
U.S. Pat. No. 4,892,460 patent by claiming to be "aerodynamically designed" requires one curved piece to be attached at one end to a conventional planar rectangular blade. Using two pieces for each blade adds extreme costs in both the manufacturing and assembly of the ceiling itself. Furthermore, the grooved connection point in the devices would appear to be susceptible to separating and causing a hazard to anyone or any property beneath the ceiling fan itself. Such an added device also has necessarily less than optimal aerodynamic properties.
Tilted type design blades have also been proposed over the years, for example in U.S. Pat.No. D451,997.
However, none of the prior art modifies the design of blades by providing a downward winglet towards the end of the blade and holes in the blade to optimize energy consumption and airflow, and reduce wobble and noise problems.
Thus, the need exists for better performing ceiling fan blades over the prior art.
OBJECTS OF THE INVENTION
The principal object of the present invention is to provide a blade for ceiling fan with downward winglet.
Another object of the present invention is to provide a blade for ceiling fan with downward winglet for higher air delivery.

Yet another object of the present invention is to provide a blade for ceiling fan with downward winglet for better air speed.
Still another object of the present invention is to provide a blade for ceiling fan with downward winglet for better strength and to reduce wobbling of blade.
At the outset of the description that follows, it is to be understood that the ensuing description only illustrates a particular form of this invention. However, such a particular form is only an exemplary embodiment and is not intended to be taken restrictively to imply any limitation on the scope of the present invention.
SUMMARY OF THE INVENTION
The present invention provides a fan blade with a winglet pointing in the downward direction resulting in higher air delivery, lower power consumption, and better air spread as compared to conventional ceiling fan.
The winglet reduces the vortices at the tip of the blade resulting in higher air delivery and spread.
BRIEF DESCRIPTION OF THE DRAWINGS
It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments.
Fig. 1 shows the bottom view of the ceiling fan with the blades according to one of the embodiments of the present invention
Fig. 2 shows the perspective view of the ceiling fan blade according to second embodiment of the present invention

Fig. 3 shows the perspective view of the ceiling fan blade according to another embodiment of the present invention
Fig. 4 shows the perspective view of the ceiling fan blade according to second embodiment of the present invention
It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative systems embodying the principles of the present subject matter. Similarly, it will be appreciated that any flow charts, flow diagrams, state transition diagrams, pseudo code, and the like represent various processes which may be substantially represented in computer readable medium and executed by a computer or processor, whether or not such computer or processor is explicitly shown.
In the present disclosure, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.
While the present disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described in detail below. It should be understood, however that it is not intended to limit the present disclosure to the particular forms disclosed, but on the contrary, the present disclosure is to cover all modifications, equivalents, and alternative falling within the spirit and the scope of the present disclosure.

The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, device or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or device or method. In other words, one or more elements in a system or apparatus proceeded by "comprises... a" does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.
In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.
The present invention will be described in detail below with reference to an embodiment as shown in the drawing.
Referring to Fig. 1, a fan with blades with downward winglet at the tip end is disclosed.
The instant invention discloses a home ceiling fan with the blades (101) having a downward winglet (102) at the tip end (101a). In various embodiments, the blades have variable width across motor end (101b) to tip end (101a) with variable twist angle in metallic material for higher air delivery with higher spread in ceiling fan.
A ceiling fan with motor, blades, bottom cover and canopies. Canopies of fan and down rod cover are designed for matching with the motor profile to make the fan

more attractive. Blade lower profile is also matching with the decorative plate fixed in bottom cover to improve the aesthetics of the fan.
Another thinner edge of the blade is called the trailing edge of blade which increases the downward pressure in the air to start flowing of the air inside the room. There is an angle make between the leading and trailing edge of the blade which is called as Twist angle of the blade. The Twist angle in the blade varies from motor end to tip end for making the pressure balance on the blade during rotation. There is also depth in the blade which plays the role for increasing or decreasing the air velocity during rotation of the fan. Here the present ceiling fan blade is designed with the new blade (101) with a winglet (102) facing downwards at the tip end (101a).
The width of the blade from motor end (101b) to tip end (101a) is variable. Variable width of the blade along with the twist angle decides the volume of the air thrown from the particular area of blade. The present ceiling fan blade (101) has optimized width and twist angle across the blade for giving maximum air delivery from the fan in given sweep at a particular speed. It also shows the motor end in round shape, which is designed to keep the Ceiling fan in seamless aesthetics after installation of all three blades in the motor.
According to the present invention, the winglet (102) is an integrated part of the ceiling fan blade (101) and is bent at an angle between 5 to 30 degrees.
Referring to Fig. 2, according to one of the embodiments the width of the blade is increasing from the motor end (101b) of the ceiling blade (101) to the tip end (101a) of the ceiling fan blade (101).
Referring to Fig. 3, according to one of the embodiments the width of the blade is decreasing from the motor end (101b) of the ceiling blade (101) to the tip end (101a) of the ceiling fan blade (101).

Referring to Fig. 3, according to another embodiment of the present invention the width of the blade is constant the motor end (101b) of the ceiling blade (101) to the tip end (101a) of the ceiling fan blade (101).
Following table discloses the increase in overall efficiency of the fan with blade having downward winglet at the tip end:

Parameters Blade with straight Winglet (w/o any bend) Blade with bend in Winglet ( Present Invention) Improvement observed
Air Delivery ( CMM) X 1.07X- 1.1X 7-10%
Torque (N-m) X 0.93X- 0.9X 7-10%
Force(Y direction) N X 0.9X-0.85X 10-15%
The change in shape has caused the redistribution of pressure at the end region of blade profile. As a result, net drag force on the blade has come down by 10-15 % leading to reduction in torque by 7-10 %.
It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various assembly that, although not explicitly described or shown herein, embody the principles of the present subject matter and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation

to such specifically recited examples and conditions. The novel features which are believed to be characteristic of the present subject matter, both as to its organization and method of operation, together with further objects and advantages will be better understood from the aforementioned description when considered in connection with the accompanying figures.
These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of "comprising" or "including" also contemplates embodiments that "consist essentially of or "consist of the recited feature.
Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present subject

matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter.

We Claim:

A ceiling fan blade (101) for high air delivery in ceiling fan system (100), the ceiling fan blade (101) comprising:
a rotor end (101b) towards rotor of the ceiling fan (100), wherein the rotor end (101b) has a rib structure;
a tip end (101a) at distal end of the ceiling fan blade (101);
wherein the tip end of the ceiling fan blade (101) has an integrated winglet (102) facing downwards.
The ceiling fan blade (101) as claimed in claim 1, wherein the ceiling fan blade (101) is made up of metallic material.
The ceiling fan blade (101) as claimed in claim 1, wherein the width of the ceiling fan blade (101) increases from the rotor end (101b) of the ceiling fan to the tip end (101a) of the ceiling fan blade (101).
The ceiling fan blade (101) as claimed in claim 1, wherein the width of the ceiling fan blade (101) decreases from the rotor end (101b) of the ceiling fan to the tip end (101a) of the ceiling fan blade (101).
The ceiling fan blade (101) as claimed in claim 1, wherein the width of the ceiling fan blade (101) remains constant throughout the rotor end (101b) of the ceiling fan to the tip end (101a) of the ceiling fan blade (101).
The ceiling fan blade (101) as claimed in claim 1, wherein the winglet (102) is bent at angle between 5 to 30 degrees.