Patent Application
20130149144
1. Technical Field of the Invention
The present invention relates in general to windmill structures. More specifically, the present invention relates to a windmill for converting wind energy to other forms of energy employing a power generator.
2. Description of the Related Art
A windmill is a machine that converts wind energy into usable energy through the rotation of adjustable wind-engaging blades. Conventionally, the energy generated by a windmill has been used to grind food grains and for pumping water. There are two classes of windmill, horizontal axis windmill and vertical axis windmill. Horizontal axis windmills are more efficient.
Over the past decades, vertical axis windmills are commonly used. Its inefficiency of operation led to the evolution of the legion horizontal axis designs. There are a variety of vertical windmills such as tower mill, fan mill, post mill, and the smock mill. The earliest design is the post mill. This design gives flexibility to the mill operator because the windmill can catch the maximum wind depending on the direction of the wind.
Wind energy is a renewable kind of energy and it is a powerful source as well. The amount of electricity produced depends upon the size of the windmill. The shaft can drive stronger if the structure of the windmill is bigger, and thus the electricity produced will be greater. The wind catching by the windmill depends upon the wind-engaging blades. The shape of the wind-engaging blade is a main component which can boost the wind catching. When the wind flows over the blades, these blades collect kinetic energy. Then the blades, which are connected onto a shaft, revolve slowly and produce the rotating force into the gearbox. The gearbox then modifies this rotating force. At that moment, the generator, which is connected to the gearbox, creates electricity.
Currently straight panels are used as the wind-engaging blades. While using straight panels there is a chance of higher drag. Drag co-efficient is a factor which affects wind catching. Wind catching is higher where there is less drag. Straight panels have greater drag when compared to other types of panels. So the present inventions have limitations. Also, the present inventions need large vertical and horizontal space. As a result manufacturing cost is also high while the overall efficiency is less.
Hence, it can be seen, that there is a need to find an optimum blade shape that will increase the overall electrical generation productivity of a windmill. Such a needed device would achieve the maximum rotation with minimal wind speed. Further, the needed device could be produced with minimal manufacturing cost. The needed device would have larger surface area on blades so it could achieve maximum rotation with minimal wind speed.
To minimize the limitations found in the prior art, and to minimize other limitations that will be apparent upon the reading of the specifications, the present invention is a windmill structure for converting wind energy to electrical energy. The windmill structure consists of a thrust holding foundation having a plurality of holes for fixing the windmill structure on a ground surface. A tower having a bottom end and a top end where the bottom end being positioned at a middle portion of the foundation and a plurality of wind-engaging blades extended from the top end of the tower. The plurality of wind-engaging blades is arranged in a plurality of levels. The windmill structure has minimum three levels of the plurality of wind-engaging blades. A plurality of concave panels with larger surface area may be used as the plurality of wind-engaging blades. The shape and size of the plurality of wind-engaging blades affects the speed of rotation of the plurality of wind-engaging blades. The employment of the plurality of concave panels facilitates to minimize the drag co-efficient. Drag co-efficient is a main factor which affects the amount of wind catching. The surface where there is less drag will have greater wind catching. The plurality of concave panels has less drag co-efficient when compared to straight panels. A plurality of supporting structures is provided for attaching the plurality of wind-engaging blades on the top end of the tower and a power generator molded at the top, middle, or bottom end of the tower. The arrangement of the plurality of wind-engaging blades facilitates to attain maximum rotation with minimal wind energy thereby increasing the overall efficiency of the windmill structure. The height of the tower affects the productivity of the windmill structure. The windmill structure with higher height is more productive. It will be due to the fact that the wind speed increases with the height of the tower.
The plurality of wind-engaging blades arranged in the plurality of levels is according to a formula: the angle between wind-engaging blades on each level=360 degrees/the number of wind-engaging blades on each level. The plurality of wind-engaging blades attached to the top end of the tower utilizes the plurality of supporting structures. The plurality of supporting structures may be a lattice type or a network arrangement. The plurality of supporting structures contributes the facility to rotate freely around the axis of the windmill structure. The plurality of wind-engaging blades has an outer curve and an inner curve. The inner curve, arranged in a concave manner, may be the catching surface. The plurality of concave panels is capable to catch the wind from any direction. The arrangement of the plurality of concave panels enables to reinforce the adjacent panel and thereby increases the speed of the rotation of the plurality of wind-engaging blades. The plurality of concave panels facilitates to catch the wind energy from any direction and is capable to channel the wind energy to the adjacent concave panel. The plurality of concave panels is positioned at a different angle to attain maximum rotation. The angle between the first concave panel in the first level and the first panel in the last level is according to a formula based on the optimal catch angle which ranges from 150 to 210 degrees. The first concave panel in the first level will be placed at 0 degrees. The offset for placement of the first concave panel in the second level will be calculated as follows: optimal catch angle/(the number of levels minus 1). The arrangement facilitates to catch maximum wind energy from any direction. The plurality of wind-engaging blades with larger surface area helps to rotate with minimal wind energy.
One objective of the invention is to provide a windmill structure for converting wind energy to electrical energy with low manufacturing cost.
Another objective of the invention is to provide a plurality of wind-engaging blades with larger surface area to attain maximum rotation with minimal wind energy.
A third objective of the invention is to provide a windmill structure with unique arrangements of a plurality of concave panels as a plurality of wind-engaging blades.
Another objective of the invention is to provide a plurality of wind engaging blades arranged in a plurality of levels to catch optimal wind energy from any direction.
Yet another objective of the invention is to provide a windmill structure with easy manufacturing and better efficiency.
These and other advantages and features of the present invention are described with specificity so as to make the present invention understandable to one of ordinary skill in the art.
Elements in the figures have not necessarily been drawn to scale in order to enhance their clarity and improve understanding of these various elements and embodiments of the invention. Furthermore, elements that are known to be common and well understood to those in the industry are not depicted in order to provide a clear view of the various embodiments of the invention, thus the drawings are generalized in form in the interest of clarity and conciseness.
In the following discussion that addresses a number of embodiments and applications of the present invention, reference is made to the accompanying drawings that form a part of hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be made without departing from the scope of the present invention.
Various inventive features are described below that can each be used independently of one another or in combination with other features. However, any single inventive feature may not address any of the problems discussed above or only address one of the problems discussed above. Further, one or more of the problems discussed above may not be fully addressed by any of the features described below.
The foregoing description of the preferred embodiment of the present invention has been presented for the purpose of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. For example, the windmill structure 10 may have maximum any number of levels of wind-engaging blades and in each level may have maximum any number of wind-engaging blades. Many modifications and variations are possible in light of the above teachings. It is intended that the scope of the present invention not be limited by this detailed description, but by the claims and the equivalents to the claims appended hereto.
