DESC:FIELD OF THE INVENTION
The present invention relates to a cleaning brush. More particularly, the present invention relates to a cleaning brush adapted for solar photo voltaic (PV) module.
BACKGROUND OF THE INVENTION
Since the past decade, solar PV module are widely used in the field of power generation. Solar module is a device that converts solar energy directly into electrical energy using photovoltaic cells wherein electricity is produced on illumination by sun light. These solar modules are installed outdoors in order to achieve a direct impact from sun light. The accumulation of dust on the modules surface reduces the power generation efficiency of the solar PV modules. Therefore, in order to maintain the power generation efficiency of the solar modules, it is important to clean the solar module periodically.
The top surface of the solar module consists of a glass surface that is surrounded by an aluminum frame. While cleaning the surface of the solar module using a rotating brush especially with helical flutes of bristles, the dust that moves from the glass surface is swept downwards and ahead in the direction of the motion of brush. As the dust is swept, it gets trapped in the interface between the frame and the glass.
The available cleaning brushes can clean the surface of the module satisfactorily, however the ends of the glass at the interface remain unclean, and the dust builds up. This is not good for the module, if not cleaned properly the dust that builds up can absorb water and harm the module. Further, the build-up of dust can reduce the power generation efficiency of the module as well.
Such a known traditional cleaning brush is shown in Figure 1. The cleaning brush (100) of figure 1 has a rotating brush (100) moves in direction (A) for cleaning the glass surface (10) of the solar module (150). The brush (100) has uniform helically arranged bristle tufts. So, when the brush (100) rotates along (X) axis, a flow of dust is established where the dirt is moved along the direction of the linear motion of the brush (100), and also in the direction of the axis of the rotation of the brush (100). The flow of dust during cleaning is in direction (B) as shown in figure 1.
When the dust is moved in the direction of the axis of rotation (X) of the brush (100), the dirt gets trapped in the interface between the glass surface (10) and the solar module frame (20). This leads to accumulation of dust and dust build-ups (30) are formed at the interface between the glass surface (10) and the frame (20) as shown in figure 2.
Further, when dew is formed on the surface (10) of the module (150), and the dew water trickles down at the interface, the collected dust is moistened, and dried repeatedly. Thus, the dust becomes hard, sticky and difficult to clean. This build-up of dust (30) is detrimental to the power generation efficiency of the solar module (150).
Therefore, there is a dire need to address the above problem by providing a solution for cleaning the glass surface as well as the dust build up at the interface.

SUMMARY OF THE INVENTION
The present invention provides a cleaning brush for cleaning of glass surface and removal of dust build up at an interface of a solar PV module.
In an embodiment, the present invention provides a cleaning brush for cleaning of glass surface and removal of dust build up at an interface of a solar PV module, said cleaning brush comprising a brush core having a first end, a middle portion and a second end, the brush core configured to rotate around a central rotational axis (X) thereof. A first cleaning portion defined at the middle portion of the brush core, said first cleaning portion having a plurality soft bristle tuft mounted thereon in a row pattern, the soft bristle tuft having a predetermined bristle diameter, a predetermined bristle length, a predetermined tufts density, and a predetermined number of tufts. A second cleaning portion defined at the first end and second end of the brush core, said second cleaning portion having a plurality of stiff bristle tuft mounted thereon in a row pattern, the stiff bristle tuft having a predetermined bristle diameter, a predetermined bristle length, a predetermined tufts density, and a predetermined number of tufts, wherein the soft bristle tuft in the first cleaning portion facilitates cleaning of the glass surface and the stiff bristle tuft in the second cleaning portions facilitate cleaning of dust build up at the interface of the solar module.
According to an embodiment of the present invention, the row pattern of the stiff bristle tufts of the second cleaning portion is parallel or helical to the rotational axis (X) of the brush core.
According to an embodiment of the present invention, the row pattern of the soft bristle tufts of the first cleaning portion is in helical/spiral arrangement with respect to rotational axis (X) of the brush core.
According to an embodiment of the present invention, the diameter of stiff bristles is 1.05 to 3 times the diameter of the soft bristles.
According to an embodiment of the present invention, the length of stiff bristles is 1.01 to 1.2 times the length of the soft bristles.
According to an embodiment of the present invention, the density of stiff bristles tufts is 1.05 to 2 times the density of the soft bristles tufts.
According to an embodiment of the present invention, the number of tufts of stiff bristles is 1.1 to 3 times the number of tufts of the soft bristles.
According to an embodiment of the present invention, the bristles are made out of nylon, polyester, PET, PP, PBT or other similar polymer materials, or a combination thereof.
In this respect, it is to be understood that the present cleaning brush is not limited in its applications to the details of construction and arrangements of the components set forth in the following description or illustration. Those skilled in the art will appreciate that the concept of this disclosure may be readily utilized as a basis for the design of other structures, methods, and systems for carrying out the several purposes of the present cleaning brush.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and together with the description serve to explain the principles of the invention.
Figure 1 is a schematic view of cleaning using traditional cleaning brush;
Figure 2 is a side view of the solar module showing the dust build-up at the interface;
Figure 3 is a perspective view showing one embodiment of the cleaning brush of an embodiment of the present invention;
Figure 4 is another perspective view showing one embodiment of the cleaning brush of an embodiment of the present invention;
Figure 5 is one another perspective view showing one embodiment of the cleaning brush of an embodiment of the present invention; and
Figure 6 is a schematic view of cleaning using cleaning brush of an embodiment of the present invention.
Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.
DETAILED DESCRIPTION OF THE INVENTION
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of the invention as defined by the description. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
The terms and words used in the following description are not limited to the bibliographical meanings but are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of the present invention is provided for illustration purpose only.
It is to be understood that the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.
The term "interface" herein means the space or surface between the glass surface of the solar module and the frame of the frame of solar module, also includes the glass surface adjacent to the frame and the frame surface adjacent to the glass surface of the solar module.
The term "brush core" herein means the cylindrical roller where the bristles are fixed or mounted.
Figures 3 - 6 show a cleaning brush (200) according to the present invention. The cleaning brush (200) comprises a first cleaning portion (50) and a second cleaning portion (60). In an embodiment, the first cleaning portion (50) comprises a plurality soft bristle (70) tuft mounted on the brush core (40). In an embodiment, the second cleaning portion (60) comprises a plurality of stiff bristle (80) tuft mounted on the brush core (40). In an embodiment, the bristle tufts of the first cleaning portions (50) are mounted in a row pattern at the middle portion of the brush core (40) such that the glass surface (10) of the solar module (150) is cleaned without getting scratched or damaged. The bristle tufts of the second cleaning portions (60) are mounted in a row pattern at both ends of the brush core (40) and preferably adjacent to the bristles of the first cleaning portions (50) at both ends such that the bristle tufts of the second cleaning portions (60) help to clean the extra dust that is caught in the interface and the interface is cleaned properly. In an embodiment, the said row pattern may be parallel to the rotational axis (X) of the brush core (40) or may be in helical/spiral arrangement with respect to rotational axis (X) of the brush core (40). In an embodiment, the bristles are made out of nylon, polyester, PET, PP, PBT or other similar polymer materials, or using pieces of cloth arranged in similar patterns or a combination of these materials.
The combination of first cleaning portion (50) and second cleaning portion (60) provides gentle cleaning to the glass surface (10) and the deep cleaning to the interface. In an embodiment, the first cleaning portion (50) has helically arranged tufts of bristles with multiple helixes arranged around the circumference of the brush core (40) as shown in Fig.3, 4 and 5. In an embodiment, the second cleaning portion (60) has the tufts arranged in a straight line around the circumference of the brush core (40) as shown in Fig.3, 4 and 5. The tufts in a straight line ensures that the dust is swept ahead of the brush (200) and not towards the glass-frame interface where the dust gets collected and become hard.
In an embodiment, the first cleaning portion (50) comprises a plurality soft bristle (70) tuft mounted on the brush core (40). In an embodiment, the second cleaning portion (60) comprises a plurality of stiff bristle (80) tuft mounted on the brush core (40).
In an embodiment, the diameter of the stiff bristles (Dstiff) is in the range between 1.05 to 3 times the diameter of the soft bristles (Dsoft) i.e., 3(Dsoft) > (D Dstiff) > 1.05(Dsoft). The bristles having diameter in this range are stiffer and proficient in cleaning hard, sticky dirt. In an embodiment, the diameter of the soft bristles (Dsoft) in the range between 0.1-0.3 mm. However, it is understood that the diameter of the soft bristles (Dsoft) may vary as per the size of cleaning brush in alternative embodiments of the present invention.
In another embodiment, the length of the stiff bristles (Lstiff) is in the range between 1.01 to 1.2 times the length of the soft bristles (Lsoft) i.e., 1.2 (Lsoft) > (Lstiff) > 1.01(Lsoft). The bristles having length in this range provides greater depth of cleaning, and ability to reach in the nooks and corners of the interface area of the glass-frame in the solar module (150). In an embodiment, the length of the soft bristles (Lsoft) is in the range between 50-80 mm. However, it is understood that the length of the soft bristles (Lsoft) may vary as per the size of cleaning brush in alternative embodiments of the present invention.
In yet another embodiment, the density of stiff bristles tufts (?stiff) on the brush core (40) is in the range between 1.05 to 2 times the density of the soft bristles tufts (?soft) on the brush core (40) i.e., 2 (?soft) > (?stiff) > 1.05(?soft). The bristles having density in this range ensures that the contact is always maintained between the brush (200) and the surface to be cleaned, thus the dust is swept away effectively. In an embodiment, the density of soft bristles tufts (?soft) is in the range between 5-15 tufts per 100 mm of each flute of tuft of brush (200) length. However, it is understood that the density of the soft bristle tufts(?soft) may vary as per intended use in alternative embodiments of the present invention.
In one another embodiment, the number of tufts of the stiff bristles (Tstiff) is in the range between 1.1 to 3 times the number of tufts of the soft bristles (Tsoft) i.e., 3 (Tsoft) > (Tstiff) > 1.1 (Tsoft). The number of tufts in this range ensures that the number of sweeps are effectively doubled for each rotation of the brush (200), thus ensuring that all residual dust is carried away. In an embodiment, the number of tufts of the soft bristles (Tsoft) is in the range between 4-12 tufts along the circumference of the brush core (40). However, said number of tufts (Tsoft) may vary as per the size of the cleaning brush (200) in other alternative embodiments of the present invention.
For example, in an embodiment, the cleaning brush (200) of the present invention includes 0.2 mm diameter fibres as soft bristles (70) in the first cleaning portion (50) whereas 0.3 mm diameter fibres as stiff bristles (80) in the second cleaning portion (60). The helixes in the normal area are 6 start, 3 pitches per meter of brush length where the distance between the neighbouring tufts in a single helix is about 18 mm and length of bristles of 59 mm, while in the deep clean area, the bristle tufts are 12 tufts around the circumference, and the distance between adjoining tufts as 15 mm and length of bristles of 66 mm.
Thus, the cleaning brush (200) of the present invention provides improved cleaning performance and thus eliminates the use of an additional brush, additional motor, or any additional device. The cleaning brush (200) of the present invention is able to clean the cleaning area gently so as to avoid causing any scratches on the glass, while getting improved and deeper cleaning performance at the interface areas. The cleaning brush (200) is powered by at least a motor to rotate along a central rotational axis (X) and moves in direction (A) for cleaning the glass surface (10) of the solar module (150), the cleaning brush (200) also ensures that the motor does not have to delivery greater power to drive the brush, as only a small portion of the bristles are stiff. On the contrary, if the entire brush is manufactured using stiff bristles, then the motor would have to supply greater power to rotate the brush. The cleaning brush (200) of the present invention is cost efficient and easy to use and achieves very high cleaning performance.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems, and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.
,CLAIMS:
1. A cleaning brush (200) for cleaning of glass surface (10) and removal of dust build up at an interface of a solar PV module (150), said cleaning brush comprising:
a brush core (40) having a first end, a middle portion and a second end, the brush core (40) configured to rotate around a central rotational axis (X) thereof;
a first cleaning portion (50) defined at the middle portion of the brush core (40), said first cleaning portion (50) having a plurality soft bristle (70) tuft mounted thereon in a row pattern, the soft bristle (70) tuft having a predetermined bristle diameter (Dsoft), a predetermined bristle length (Lsoft), a predetermined tufts density (?soft), and a predetermined number of tufts (Tsoft); and
a second cleaning portion (60) defined at the first end and second end of the brush core (40), said second cleaning portion (60) having a plurality of stiff bristle (80) tuft mounted thereon in a row pattern, the stiff bristle (80) tuft having a predetermined bristle diameter (Dstiff), a predetermined bristle length (Lstiff), a predetermined tufts density(?stiff), and a predetermined number of tufts (Tstiff),
wherein the soft bristle (70) tuft in the first cleaning portion (50) facilitates cleaning of the glass surface (10), the stiff bristle (80) tuft in the second cleaning portions (60) facilitate cleaning of dust build up at the interface of the solar module (150).

2. The cleaning brush (200) as claimed in claim 1, wherein the said row pattern of the stiff bristle (80) tufts of the second cleaning portion (60) is parallel or helical to the rotational axis (X) of the brush core (40).

3. The cleaning brush (200) as claimed in claim 1 or 2, wherein the said row pattern of the soft bristle (70) tufts of the first cleaning portion (50) is in helical/spiral arrangement with respect to rotational axis (X) of the brush core (40).

4. The cleaning brush (200) as claimed in claim 1, wherein the bristles (70, 80) are made out of nylon, polyester, PET, PP, PBT or other similar polymer materials, or a combination thereof.

5. The cleaning brush (200) as claimed in claim 1, wherein the diameter (Dstiff) of stiff bristles (80) is 1.05 to 3 times the diameter (Dsoft) of the soft bristles (70).

6. The cleaning brush (200) as claimed in claim 1, wherein the length (Lstiff) of stiff bristles (80) is 1.01 to 1.2 times the length (Lsoft) of the soft bristles (70).

7. The cleaning brush (200) as claimed in claim 1, wherein the density of stiff bristles tufts (?stiff) is 1.05 to 2 times the density(?soft) of the soft bristles tufts (70).

8. The cleaning brush (200) as claimed in claim 1, wherein the number of tufts (Tstiff) of stiff bristles (80) is 1.1 to 3 times the number of tufts (Tsoft) of the soft bristles (70).