Claims:CLAIMS

We Claim:

1. An apparatus (100) for cleaning an array of photovoltaic (PV) panels, the apparatus (100) comprising:
a plurality of brush units (105) disposed proximate to each other between a pair of end plates (110A, 110B);
a plurality of support plates (115) disposed between the pair of end plates (110A, 110B), wherein the plurality of support plates (115) is placed at regular intervals to hold the plurality of the brush units (105), wherein at least a portion of mutually adjacent ends of the brush units (105) overlap each other, and wherein the axes (150, 155) of each of mutually adjacent brush units (105) is laterally offset with respect to each other; and
a plurality of drive units (120) coupled to each of the plurality of brush units (105), wherein each of the plurality of the drive units (120) is configured to rotate the plurality of brush units (105), and
a microcontroller (160) communicatively coupled to a plurality of motion sensors (165) disposed on the pair end plates (110A, 110B), wherein the microcontroller (160) is configured to drive the apparatus (100) along the PV panels based on one or more parameters sensed by the plurality of motion sensors (165).

2. The apparatus (100) as claimed in claim 1, wherein each of the plurality of drive unit (120) comprises a drive shaft (125) coupled to a motor (127).

3. The apparatus (100) as claimed in claim 2, wherein each of the brush units (105) comprises a brush (130) coupled to the drive shaft (125) of the respective drive unit (120).

4. The apparatus (100) as claimed in claim 2, wherein each of the plurality of drive units (120) comprises an angle (122) for fixing brush units (105) to the structure of the apparatus (100), and a brush lever (124).

5. The apparatus (100) as claimed in claim 4, wherein the drive shaft (125) passes through the angle (122) and is coupled to a brush (130) at one end and the motor (127) at the other end.

6. The apparatus (100) as claimed in claim 4, wherein the brush lever (124) comprises bearings (126) and a polyurethane damper (128) for allowing and withstanding vertical adjustments for accommodating vertical movements of the drive shaft (125) due to undulation in panel arrangement to always move on the panel frame.

7. The apparatus (100) as claimed in claim 1, further comprising a motion transmitting unit (140) coupled to the plurality of support plates (115) and the brush units (105) to transmit motion from one brush unit (105) to an adjacent brush unit in the absence of a drive unit dedicated to a brush unit from the plurality of brush units (105).

8. The apparatus (100) as claimed in claim 7, wherein the motion transmitting unit (140) comprises a pulley and belt drive (145) for rotating the adjacent drive shaft (125) in same direction.

9. The apparatus (100) as claimed in claim 7, wherein the motion transmitting unit (140) comprises a two-lever assembly (140-1, 140-2) connected to the adjacent drive shaft (125) for allowing vertical adjustments for accommodating vertical movements of the brush due to undulation in panel arrangement.

10. The apparatus (100) as claimed in claim 7, wherein the motion transmitting unit (140) comprises damper rollers to absorb shocks due to movements of the brush assembly.

11. The apparatus (100) as claimed in claim 1, wherein the one or more parameters sensed by the plurality of motion sensors (165) comprise: a start position of the apparatus (100), an end position of the apparatus (100), wind speed, rain, hotspot, dust, and brush rotation speed.

12. The apparatus (100) as claimed in claim 11, wherein the plurality of motion sensors (165) is connected to a controller via a network server, to send and receive signals to and from a controller.

13. The apparatus (100) as claimed in claim 1, further comprising a rechargeable battery and a charging unit (180), wherein the charging unit (180) is configured to charge the rechargeable battery of the apparatus.

14. The apparatus (100) as claimed in claim 13, wherein the charging unit (180) comprises a plurality of pair of plunger connector and actuator (182) configured to latch on to a stationary power supplying panel for recharging.

15. The apparatus (100) as claimed in claim 1, further comprising a first support structure sub assembly (190) to provide structural support to the apparatus (100).

16. The apparatus (100) as claimed in claim 15, wherein the first support structure sub assembly (190) is adjustable to vary the length of the apparatus (100).

17. The apparatus (100) as claimed in claim 1, further comprising a second support structure sub assembly (195), wherein the second support structure sub (195) assembly is adjustable to vary the length of the apparatus (100).

18. The apparatus (100) as claimed in claim 17, wherein the second support structure sub assembly (195) is configured to increase overlapping of the brush units to accommodate a decrease in length of the apparatus (100).

19. The apparatus (100) as claimed in claim 17, wherein the second support structure sub assembly (195) is configured to decrease overlapping of the brush units to accommodate an increase in length of the apparatus (100).

20. The apparatus (100) as claimed in claim 1, wherein each of the pair of end plates (110A, 110B) comprises a plurality of side polyurethane (PU) wheels (200) and a plurality of traction wheels (205) for enabling sliding movement of the apparatus (100) over the PV panels.

21. The apparatus (100) as claimed in claim 1, wherein each of the pair of end plates (110A, 110B) comprises bevel gears (210) for allowing and withstanding vertical adjustments for accommodating horizontal offsets in the array of PV panels that are to be cleaned and ensure that the apparatus always moves only on the panel frames and never on the panel glass.

22. The apparatus (100) as claimed in claim 1, further comprising a solenoid based apparatus locking system (1100) configured to lift a lock (1105) to enable forward movement of the apparatus (100), wherein the stationary charging panels are cleaned by the apparatus (100) as the charging unit (180) comprising the stationary charging panels is positioned on the same horizontal plane as of the main panels (PV panels).
Dated this 13th day of February 2022

Chaitanya Rajendra Zanpure
Agent for Applicant
IN-PA-2282
, Description:FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
The Patents [Amendment] Rules, 2006
COMPLETE SPECIFICATION

(See section 10 and rule 13)

1. TITLE OF THE INVENTION

AN APPARATUS FOR CLEANING AN ARRAY OF PHOTOVOLTAIC (PV) PANELS

2. APPLICANT

NAME : INDISOLAR PRODUCTS PRIVATE LIMITED
NATIONALITY : Indian
ADDRESS : 34, Nakshatra villas, Balapur, Hyderabad, 500005, Telangana

3. PREAMBLE TO THE DESCRIPTION

COMPLETE

The following specification particularly describes the invention and the manner in which it is performed.

 
AN APPARATUS FOR CLEANING AN ARRAY OF PHOTOVOLTAIC (PV) PANELS

TECHNICAL FIELD:

The present disclosure relates to solar panels, and more particularly, to an apparatus for cleaning an array of photovoltaic (PV) panels.

BACKGROUND:

Solar energy is one of the fastest growing sources of renewable energy. Generally, the solar plants comprise Photovoltaic (PV) panels, wherein the PV panels include PV rows laid in array of rows and columns. Further, the array of PV rows can be arranged either in portrait or landscape configuration.

Often, due to natural undulations, the solar panel surface (PV rows) suffers from misalignment resulting in improper and non-uniform cleaning when robotic cleaners are employed. Also, improper installation of the PV rows creates vertical misalignments/vertical differences /variations in the solar panel surfaces (PV rows). Such differences too may lead to improper and non-uniform cleaning with robotic cleaners. Commercially, many cleaning apparatuses are available for cleaning the solar panels such as, manually operated cleaning brush, self-powered brush, automatic cleaning system and robotic cleaning apparatuses. Each of the cleaning apparatuses have drawbacks with respect to handling mis-alignments and offsets.

Generally, the solar plants stretch across large area, for this reason long sized cleaning brushes are used. Typically, due to the own weight of the cleaning brushes themselves, and also after some time deflection occurs in these long brushes and forms a curved profile in the cleaning brushes, resulting in improper and non-uniform cleaning. Further, improper cleaning of panels causes dust accumulation on the surface of the panels that may lead to spotting, solidification and hotspot formation. Once the hotspots are formed, the panels begin to degrade rapidly as the hotspots act as shunt and drain power.

Further, with regards to solar panel laying, it is seldom that the panels are perfectly laid as per design and the usual problem is presence of vertical and horizontal offsets present length-wise and breadth-wise along the rows and columns of the laid panels. In such scenarios, if the brushes of a cleaning apparatus are rigidly fixed and not flexible to suit the vertical offsets both in between the panels and at the side edges of the panel rows, a trail of dust may be left on the panels even after cleaning. In other scenario, extra load may be exerted on the panels that may cause stoppage of robot, at certain places on the laid PV panels where offsets are found. When the offsets are horizontal, robot may slip out of panel and this may cause damage to the panel glass/cell. This may lead to damaging of the glass panels by the robot when the robot gets stuck at mis-aligned portion. When the offsets are vertical, then this may leave a trail of dust at the height differences. Further, in the eventuality of wedging, getting stuck or robot going cross on the panels due to an obstruction, or due to misalignments beyond a certain range, the robot wheels may go away from the panel frame edges and thereby increasing the possibility that the robot’s metallic components may damage the panel glass.

In another scenario, when the robot is at rest at its docking station, there is a strong possibility of robot freewheeling forward on the panel due to heavy winds.

Furthermore, typical automatic/self-charging/robotic cleaning apparatus having rechargeable lithium batteries that are charged by PV panels mounted on surface of the cleaning apparatus itself. This charging system works fine for the panel rows that are short in length. If the PV row needs to be cleaned every day, then the battery capacity and associated charging panel capacity to charge the battery fully should be adequate. However, the surface area of the cleaning apparatus is limited and therefore its charging capacity is also limited. Further, such PV panels (mounted on surface of the cleaning apparatus for charging the batteries) pose additional weight on the solar panels which would result in battery drain of the cleaning apparatus and as well may damage the panels.

This system of charging mentioned above, works fine for panel rows that are short in length since the surface area available on top of the robot is limited. If the PV row is required to be cleaned every day, then the battery capacity and associated charging panel capacity to charge the battery fully in one day should be adequate to achieve daily cleaning. However, since the surface area of the robot is limited and therefore its charging capacity is also limited which poses a serious limitation regarding autonomous and self-reliant power source for the robot.

Additional problem may occur with respect to cleaning the auxiliary panels (used for charging the battery of the apparatus) itself. It has to be carefully determined whether the auxiliary panels are placed on top of the robot or away from the robot. The auxiliary panels need to be cleaned along with the main panels in the row, for effective charging.

In scenarios, when the auxiliary panels are placed away from the robot, it means that they will not move along with the robot and therefore there will be electrical disconnect between the auxiliary panels and the battery when the robot is operating. Therefore, the problem of charging the batteries and connecting the panels to the charging system in the robot would arise. This will require a special type of electrical connector that connects the charging panels to the battery when the robot arrives at its docking position after performing cleaning operation. The mechanism would be that charges the robot when its stationary and when the robot moves the robot is not charging but drawing power from the charged battery.

Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of described systems with some aspects of the present disclosure, as set forth in the remainder of the present application and with reference to the drawings.

SUMMARY OF THE INVENTION:

In accordance with one embodiment, an apparatus for cleaning an array of photovoltaic (PV) panels is disclosed. The apparatus includes a plurality of brush units disposed proximate to each other between a pair of end plates. The apparatus further includes a plurality of support plates disposed between the pair of end plates. The plurality of support plates is placed at regular intervals to hold the plurality of the brush units. At least a portion of mutually adjacent ends of the brush units overlap each other. The axes of each of mutually adjacent brush units may be laterally offset with respect to each other. The apparatus further includes a plurality of drive units coupled to each of the plurality of brush units. Each of the plurality of the drive units may be configured to rotate the plurality of brush units. The apparatus further includes a microcontroller communicatively coupled to a plurality of motion sensors disposed on the pair end plates. The microcontroller may be configured to drive the apparatus along the PV panels based on one or more parameters sensed by the plurality of motion sensors.

Further, each of the plurality of drive unit includes a drive shaft coupled to a motor. Also, each of the brush units includes a brush coupled to the drive shaft of the respective drive unit. Each of the plurality of drive units includes an angle for fixing brush units to the structure of the apparatus, and a brush lever. The drive shaft passes through the angle and is coupled to a brush at one end and the motor at the other end. The brush lever includes a bearing and a polyurethane damper for allowing and withstanding vertical adjustments for accommodating vertical movements of the brush due to undulation in panel arrangement.

In another aspect of the above embodiment, the parameters sensed by the plurality of sensors include, but not are limited to a start position of the apparatus, an end position of the apparatus, wind speed, rain, hotspot, dust, and brush rotation speed. The plurality of sensors (165) is connected to a controller via a network server, to send and receive signals to and from a controller.

In one aspect of the above embodiment, the apparatus includes a motion transmitting unit coupled to the plurality of support plates and the brush units to transmit motion from one brush unit to an adjacent brush unit, in the absence of a drive unit dedicated to a brush unit from the plurality of brush units. The motion transmitting unit includes a pulley and belt drive for rotating the adjacent drive shaft in same direction. The motion transmitting unit includes a two-lever assembly connected to the adjacent drive shaft for allowing vertical adjustments for accommodating vertical movements of the brush due to undulation in panel arrangement. The motion transmitting unit includes damper rollers to absorb shocks due to movements of the brush assembly.

In yet another aspect of the above embodiment, the apparatus includes a rechargeable battery and a charging unit, wherein the charging unit is configured to charge the rechargeable battery of the apparatus. The charging unit includes a plurality of pair of plunger connector and actuator configured to latch on to a stationary power supplying panel for recharging.

In yet another aspect of the above embodiment, the apparatus includes a first support structure sub assembly to provide structural support to the apparatus. The first support cover sub assembly may be adjustable to vary the length of the apparatus.

In yet another aspect of the above embodiment, the apparatus includes a second support structure sub assembly, wherein the second structure cover sub assembly is adjustable to vary the length of the apparatus. The second support structure sub assembly may be configured to increase overlapping of the brush units to accommodate a decrease in length of the apparatus. The second support structure sub assembly may be configured to decrease overlapping of the brush units to accommodate an increase in length of the apparatus.

In another embodiment, each of the pair of end plates includes a plurality of side polyurethane (PU) wheels and a plurality of traction wheels for enabling sliding movement of the apparatus over the PV panels. Further, each of the pair of end plates includes bevel gears for allowing and withstanding vertical adjustments for accommodating horizontal offsets in the array of PV panels that are to be cleaned.
The bevel gear mechanism will help the robot adjust the apparatus automatically when horizontal or/and vertical offsets are found in the panel laying. Further, the apparatus may include a solenoid based apparatus locking system configured to lift a lock to enable forward movement of the apparatus.

BRIEF DESCRIPTION OF THE FIGURES:

The disclosed system will be described and explained with additional specificity and detail with the accompanying figures in which:

Figure. 1A shows a top view of an apparatus for cleaning an array of photovoltaic (PV) panels according to one embodiment of the present disclosure;

Figure. 1B shows a front view of the apparatus for cleaning an array of photovoltaic (PV) panels according to one embodiment of the present disclosure;

Figure. 1C shows a top view of an apparatus having dedicated motor for each of the plurality of brush units for cleaning an array of photovoltaic (PV) panels according to one embodiment of the present disclosure;

Figure. 1D shows a front view of the apparatus having dedicated motor for each of the plurality of brush units for cleaning an array of photovoltaic (PV) panels according to one embodiment of the present disclosure;

Figure. 2A is a schematic perspective view of a drive unit of a single motor apparatus, according to one embodiment of the present disclosure;

Figure. 2B is a schematic perspective view of a drive unit of an apparatus having dedicated motor for each of the plurality of brush units, according to one embodiment of the present disclosure;

Figure. 3A shows a schematic perspective view of a support plate along with a pair of brush units according to one embodiment of the present disclosure;

Figure. 3B shows a schematic isometric view of the support plate along with the pair of brush units according to one embodiment of the present disclosure;

Figure. 3C shows a schematic perspective view of a support plate having a first support structure sub assembly and a second support structure sub assembly for adjusting the length of the apparatus, according to one embodiment of the present disclosure;

Figure. 3D shows a isometric view of a support plate having a first support structure sub assembly and a second support structure sub assembly for adjusting the length of the apparatus, according to one embodiment of the present disclosure;

Figure. 3E is a schematic perspective view of an apparatus having dedicated drive unit for the plurality of brush units, according to one embodiment of the present disclosure;

Figure. 3F is a isometric view of an apparatus having dedicated drive unit for the plurality of brush units, according to one embodiment of the present disclosure;

Figure. 3G is a schematic perspective view of an apparatus having dedicated drive unit for the plurality of brush units illustrating increased overlapping of brush, according to one embodiment of the present disclosure;

Figure. 3H is a isometric view of an apparatus having dedicated drive unit for the plurality of brush units illustrating increased overlapping of brush, according to one embodiment of the present disclosure;

Figure. 4 shows a schematic perspective view of a motion transmitting unit according to one embodiment of the present disclosure;

Figure. 5 shows a schematic perspective view of a motion transmitting unit along with a belt and pulley drive according to one embodiment of the present disclosure;

Figure. 6A depicts a front isometric view of exemplary angles through which a drive units are coupled to respective brush units, according to one embodiment of the present disclosure;

Figure. 6B depicts a back isometric view of exemplary angles through which a drive units are coupled to respective brush units, according to one embodiment of the present disclosure

Figure. 7 depicts an isometric view of the end plate using which the apparatus is mounted on the PV panels for cleaning, according to one embodiment of the present disclosure;

Figure. 8A depicts an isometric view of a charging unit having a rechargeable battery mounted on the apparatus, according to one embodiment of the present disclosure;

Figure. 8B depicts an isometric view of a charging unit having a rechargeable battery mounted on the apparatus and a plurality of pair of plunger connector and actuator, according to one embodiment of the present disclosure;

Figure. 9 depicts an isometric view of the first support structure sub assembly of the apparatus and a first mechanism for altering the length of the apparatus, according to one embodiment of the present disclosure;

Figure. 10 depicts an isometric view of the first support structure sub assembly of the apparatus and a second mechanism for altering the length of the apparatus, according to one embodiment of the present disclosure; and

Figure. 11 depicts an isometric view of an apparatus locking system for controlling the movement of the apparatus (100), according to one embodiment of the present disclosure.

Further, persons skilled in the art to which this disclosure belongs will appreciate that elements in the figures are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the figures by conventional symbols, and the figures may show only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the figures with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS:

For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiment illustrated in the figures and specific language will be used to describe them. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Such alterations and further modifications to the disclosure, and such further applications of the principles of the disclosure as described herein being contemplated as would normally occur to one skilled in the art to which the disclosure relates are deemed to be a part of this disclosure.

It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the disclosure and are not intended to be restrictive thereof.

The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such a process or a method. Similarly, one or more devices or sub-systems or elements or structures or components preceded by "comprises... a" does not, without more constraints, preclude the existence of other devices, other sub-systems, other elements, other structures, other components, additional devices, additional sub-systems, additional elements, additional structures, or additional components. Appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.

Embodiments of the present disclosure will be described below in detail with reference to the accompanying figures.

In accordance with the embodiments of the present disclosure, an apparatus for cleaning an array of photovoltaic (PV) panels is disclosed. The apparatus a plurality of brush units disposed proximate to each other between a pair of end plates. The apparatus further includes a plurality of support plates disposed between the pair of end plates. The plurality of support plates is placed at regular intervals to hold the plurality of the brush units. At least a portion of mutually adjacent ends of the brush units overlap each other. The axes of each of mutually adjacent brush units may be laterally offset with respect to each other. The apparatus further includes a plurality of drive units coupled to each of the plurality of brush units. Each of the plurality of the drive units may be configured to rotate the plurality of brush units. The apparatus further includes a microcontroller communicatively coupled to a plurality of motion sensors disposed on the pair end plates. The microcontroller may be configured to drive the apparatus along the PV panels based on one or more parameters sensed by the plurality of motion sensors.

Figure. 1A and Figure. 1B, show a top view and a front view of an apparatus (100) for cleaning an array of photovoltaic (PV) panels according to one embodiment of the present disclosure. The apparatus (100) includes a plurality of brush units (105), a pair of end plates (110A, 110B), and a plurality of support plates (115).

The plurality of brush units (105) is disposed proximate to each other between the pair of end plates (110A, 110B) to clean surface of the PV panels. The support plates (115) are disposed between the pair of end plates (110A, 110B) of the apparatus (100). Further, it is evident from the figures that the axes (150, 155) of rotation of the brushes are laterally offset. Such structural alignments of support plates (115) and the axes (150, 155) are configured to minimize deflection produced in the brush unit (105). Since, the brush unit (105) typically receives deflection due to the weight of the brush unit (105), therefore to solve the aforementioned problem, the support plates (115) are placed at regular intervals between the pair of end plates (110A, 110B) to hold the plurality of the brush units (105). In one embodiment, the plurality of brush units (105) is configured in a certain arrangement so that mutually adjacent ends of the brush units (105) overlap each other (as shown in Figure 1A). Further, it is to be noted that the apparatus (100) depicted in Figure. 1A and Figure. 1B correspond to a single motor apparatus where a single motor apparatus (100) where a single motor is configured to rotate all the brush units (105).

Figure. 1C and Figure. 1D, show a top view and a front view of an apparatus (100) having dedicated motor for each of the plurality of brush units (105) for cleaning an array of photovoltaic (PV) panels according to one embodiment of the present disclosure. The apparatus (100) includes a plurality of brush units (105), a pair of end plates (110A, 110B), and a plurality of support plates (115). With reference to Figure. 1C and Figure. 1D, there is shown an apparatus (100) that includes dedicated motor coupled to each of the brush units (105). Elements of Figure. 1C and Figure. 1D have been explained in conjunction with the elements of Figure. 1A and Figure. 1B.

In another embodiment, in addition to the elements depicted and explained in Figure. 1A and Figure. 1B, the dedicated motor apparatus (100) includes a plurality of drive units (120) coupled to each of the plurality of brush units (105). Each of the plurality of the drive units (120) is configured to rotate the plurality of brush units (105). Such dedicated motor apparatus (100) further includes a microcontroller (160) communicatively coupled to a plurality of motion sensors (165) disposed on the pair end plates (110A, 110B). The microcontroller (160) may be configured to drive the apparatus (100) along the PV panels based on one or more parameters sensed by the plurality of motion sensors (165).

Figure. 2A is a schematic perspective view of a drive unit (120) of a single motor apparatus (100), according to one embodiment of the present disclosure. The drive unit (120) is configured to drive the apparatus (100) along the PV panels and rotate the plurality of brush units (105). The drive unit (120) includes a drive shaft (125) and a motor (127) (not shown in Figure 2A). The motor (127) may be a DC motor. In one embodiment, the drive unit (120) is placed in at least one of the pair of end plates (110A, 110B) and coupled to the brush units (105) through the drive shaft (125) for allowing rotation to the plurality of brush units (105).

Figure. 2B is a schematic perspective view of a drive unit of an apparatus having dedicated motor for each of the plurality of brush units, according to one embodiment of the present disclosure. The elements of Figure. 2B are consistent with the elements of the dedicated motor apparatus (100) depicted in Figure. 1C and Figure. 1D. As shown, each brush unit (105) includes a dedicated drive unit (120) which is configured to drive the apparatus (100) along the PV panels and rotate the brush unit (105) to which the drive unit (120) is attached. The drive unit (120) includes a drive shaft (125) and a motor (127) (not shown in Figure. 2B). The motor (127) may be a DC motor. In one embodiment, the drive unit (120) may be attached to the brush unit (105) using an angle assembly (explained in detail in Figure. 6A and 6B). The dedicated drive unit (120) is coupled to a respective brush unit (105) through the drive shaft (125) for allowing rotation to the plurality of brush units (105).

Figure. 3A and Figure. 3B, are a schematic perspective view and an isometric view of a support plate (115) along with a pair of brush units (105), according to one embodiment of the present disclosure. The brush units (105) include a plurality of brushes (130). The plurality of brushes (130) is coupled on the brush shaft (135). As shown in Figure. 3A and Figure. 3B, the support plate (115) is provided to support the brush units (105) when width of the brushes (130) or length of the brushes (130) or size of the apparatus (100) is large. The support plates (115) are disposed at a predefined interval of space between the pair of end plates (110A, 110B) of the apparatus (100). For example, if the panel size of the solar plant is 2m x 1m, then the support plates (115) are placed at every 1m distance from the end plate 110A to the end plate 110B in the apparatus (100). In other example, the support plates (115) are coupled after every predefined length (either 500mm or 1000mm) of the brushes (130) of the brush units (105). The plurality of brushes (130) is extended over a certain length in order to get an appropriate touch with the surface of the PV panels to cover and clean the entire surface of the PV rows.

In one embodiment, the plurality of brushes (130) overlaps to one another beneath the support plates (115) (as shown in Figure. 3A) to cover and clean any left-out surface of PV panels. For example, the support plates (115) typically have a finite width and if there is an absence of cleaning brushes in this width, there may be dust accommodated on the panel surface below the support plates and result in strips (surface area below the support plates (115)) of the panel area that are left unclean.

Figure. 3C and Figure. 3D, are a schematic perspective view and an isometric view of a support plate (115) having a first support structure sub assembly (190) and a second support structure sub assembly (195) for adjusting the length of the apparatus (100), according to one embodiment of the present disclosure. Elements of Figure. 3C and Figure. 3D have been explained in conjunction with the elements of Figures. 1A to 3B.

In one embodiment, the apparatus (100) includes a first support structure sub assembly (190) and a second support structure sub assembly (195) to provide structural support to the apparatus (100) (as shown in Figure. 3A and Figure. 3B). The first support structure sub assembly (190) and the second support structure sub assembly (195) are adjustable to vary the length of the apparatus. In one embodiment, the second support structure sub assembly (195) is configured to increase overlapping of the brush units to accommodate a decrease in length of the apparatus. In another embodiment, the second support structure sub assembly (195) can also be is configured to decrease overlapping of the brush units (105) to accommodate an increase in length of the apparatus. The increase and decrease in the length of the apparatus may be facilitated by the adjustment provision (305) provided on the second support structure assembly (195). The adjustment provision (305) allows for sliding of the brush units (105) for increasing or decreasing an extent of overlap between the brush units, thereby leading to change in length of the apparatus (100).

Figure. 3E and Figure. 3F, are a schematic perspective view and an isometric view of an apparatus (100) having dedicated drive unit (120) for the plurality of brush units (105), according to one embodiment of the present disclosure. The brush units (105) include a plurality of brushes (130). Each of the brush unit in the plurality of brushes units (105) is coupled to a dedicated drive unit (120) having a motor for rotating the brush of the brush unit (105). Further, the coupling of the brush unit (105) and the respective drive unit (120) may be based on an angle (122) through which the drive shaft (125) passes (explained above in detail). The details on the assembly of angle (122) having brush lever (124), bearing (126), and a polyurethane damper (128) have been provided in Figure. 6A and 6B.

Similar to the embodiment depicted in Figure. 3A and Figure. 3B, the apparatus with dedicated motor is provided to support the brush units (105) when width of the brushes (130) or length of the brushes (130) or size of the apparatus (100) is large. The support plates (115) are disposed at a predefined interval of space between the pair of end plates (110A, 110B) of the apparatus (100). For example, if the panel size of the solar plant is 2m x 1m, then the support plates (115) are placed at every 1m distance from the end plate 110A to the end plate 110B in the apparatus (100). In other example, the support plates (115) are coupled after every predefined length (either 500mm or 1000mm) of the brushes (130) of the brush units (105). The plurality of brushes (130) is extended over a certain length in order to get an appropriate touch with the surface of the PV panels to cover and clean the entire surface of the PV rows.

Further, with reference to Figure. 3E and Figure. 3F, schematic perspective view and isometric view of (305) the extent of overlapping between the brushes. Using the second support structure sub assembly (195), the overlapping of the brush units (130) may be increased, thereby increasing overall length of the apparatus (100). This is done by sliding the brushes (130) along the adjustment provision (300) explained in Figure. 3C and 3D. The increased overlapping (305) between the brushes (130) of the apparatus (100) has been depicted in Figures. 3G and 3H that are also schematic perspective view and isometric view of an apparatus (100) having dedicated drive unit (120) for the plurality of brush units (105) illustrating increased overlapping of brush (130), according to one embodiment of the present disclosure.

The apparatus (100) further includes a motion transmitting unit (140). As shown in Figure. 4, the motion transmitting unit (140) includes a two-lever assembly (140-1, 140-2) connected to the adjacent brush shafts (135) for allowing vertical adjustments for accommodating vertical movements of the brush shafts (135) due to undulation in panel arrangement. The motion transmitting unit (140), further, includes one or more damper rollers (not shown in the FIG. 4). The one or more damper rollers are configured to absorb shocks due to movement of the brush units (105). In one embodiment, the motion transmitting unit (140) includes a pulley and a belt drive (145), as shown in Figure. 5. The pulley and the belt drive (145) are coupled to the two-lever assembly (140-1, 140-2), wherein the two-lever assembly (140-1, 140-2) are placed on either side of the support plate (115) in upward and downward positions. The pulley and the belt drive (145) are configured for rotating the adjacent brush shaft (135) in the same direction. A person having ordinary skill in the art will appreciate that the embodiments of Figure. 4 and 5 relate to an apparatus having a single motor apparatus (100).

For the other embodiment, where a dedicated motor is provided to each of the plurality of brush units (105), Figure. 6A and 6B depicts a front and back isometric views of exemplary angles (122) through which a drive units (120) are coupled to respective brush units (130), according to one embodiment of the present disclosure. The angle (122) further assists in fixing the assembly of the drive unit (120) and the brush unit (105) to the structure of the apparatus (100). Elements of Figure. 6A and 6B have been explained in conjunction with the elements of Figure. 1 to 5.

With reference to Figure. 6A and 6B, an exemplary angle (122) includes a brush lever (124), a plurality of bearings (126), and a polyurethane damper (128). The angle (122) may further include a vertical movement adjuster (600). In an embodiment, the plurality of bearings (126) provide an allowance for vertical movement of the brush unit (105) in scenarios when there is any vertical offsets in the PV panels on which the apparatus (100) is configured to move. To cushion the impulsive force produced during such movements, the polyurethane damper (128) is provided.

As depicted in Figure. 6B, the back isometric view of the angle (122) illustrates the mechanism using which the drive unit (120) is affixed to the angle and subsequently the respective brush unit (105). The drive shaft (125) of the drive unit (120) passes through the brush lever (124) of the angle (122). Once passed, the drive shaft (125) may be axially coupled to a brush (130) of the respective brush unit (105).

In one embodiment, the apparatus (100) includes a microcontroller (160) for monitoring various systemic parameters and status conditions such as brush rotation, transfer motion from one brush unit (105) to other brush unit (105) while operating the apparatus (100).

In one embodiment, the following steps are performed for transfer of motion from the motor (127) to brush units (105): sending a signal, by the microcontroller (160) to the drive unit (120); upon receiving the signal, the drive unit (120) actuates a power from the plurality of motors (127) of each of the plurality of drive units (120) to move the apparatus (100) in a forward direction and also transferring a rotary motion to the drive shaft (125); upon receiving the rotary motion, the each drive shaft (125) of each of the plurality of drive units (120) starts rotating on an axis of the drive shaft (125); and upon receiving the rotary motion, the brush units (105) start rotating along with the drive shaft (125).

In the embodiment where a single motor is use in the apparatus (100), the following steps are performed for transfer of motion from one brush unit (105) to other brush unit (105) placed either sides of the support plate (115) parallelly in up and down position and coupled with the two-lever assembly (140-1, 140-2): receiving the rotary motion from the brush shaft (135) to one end lever assembly (140-1) as the brush shaft (135) is rotated about an axis of the brush shaft (135) in response to the brush unit (105) rotation, passing the same rotary motion, from the one end lever assembly (140-1) to the other end lever assembly (140-2) via the pulley and the belt drive (145) as connected with the two-lever assembly (140-1, 140-2); and upon receiving the rotary motion, the other side placed brush unit (105) starts to rotate in same direction, as the other side placed brush unit (105) is coupled to the other end lever assembly (140-2)).

Figure. 7 depicts an isometric view of the end plate (110A) using which the apparatus (100) is mounted on the PV panels for cleaning, according to one embodiment of the present disclosure. Elements of Figure. 7 have been explained in conjunction with the elements of Figure. 1 to 6B.

With reference to Figure. 7, there is shown the end plate 110A that includes a plurality of motion sensors (165) for sensing various parameters including but not limited to start position of the apparatus (100), end position of the apparatus (100), wind speed, rain, hotspot, dust, and brush rotation speed. For example, if the battery charge is insufficient at start of the operation, the sensor may detect and send signal to the apparatus (100), so the apparatus (100) does not start the operation till the battery charge is enough. In another example, the sensors may detect if there is any fault with the brush units (105) and if they are not rotating at desired speed when the apparatus (100) is operating. In another example, the sensor may detect rainy conditions and decide whether the apparatus (100) may be operated or not in the rainy conditions.

Furthermore, the plurality of motion sensors (165) is connected to a controller via a network server, to send and receive signals to and from a controller. In one aspect of the associated embodiment, the apparatus (100) includes a gyroscope that will detect if the apparatus (100) is moving forward/reverse. If there is mechanical obstruction or fault due to any unforeseen condition, the gyroscope will indicate to the controller, about the condition for any further corrective action. At this instant the controller will switch off the apparatus (100) and go to sleep mode. In another aspect of the associated embodiment, the apparatus (100) includes an Electro Magnetic (EM) braking system. The EM braking system is configured to operate the apparatus (100) during high speeds of wind is encountered. For example, if the apparatus (100) is at rest, the EM braking system ensures that even at high wind speed conditions, the apparatus (100) does not drive itself due to forces of the wind. In an embodiment, the plurality of motion sensors (165) may be placed either at any one end of the plates (110A, 110B) or at the both end of the plates (110A, 110B) of the apparatus (100).

Further, the end plate (110A) includes a plurality of side polyurethane (PU) wheels (200) and a plurality of traction wheels (205) for enabling sliding movement of the apparatus (100) over the PV panels. The end plate (110A) further includes a plurality of bevel gears (210) and (215) for allowing and withstanding vertical adjustments for accommodating horizontal offsets in the array of PV panels that are to be cleaned.

In an embodiment, the plurality of bevel gears (210) and (215) may be encased in gear boxes. The gear box of the bevel gears (210) may be coupled with the plurality of traction wheels (205) and the gear box of the bevel gears (215) may be coupled with the plurality of traction wheels (200). When a horizontal offset is encountered between two panels, the gear mechanism of the plurality of bevel gears (210) and (215) may automatically climb over the offset (positive) and adjust (negative) itself for negative offsets. As the bevel gear mechanism of the plurality of bevel gears (210) and (215) is always fitted at the top side of the apparatus (100), this works efficiently as the apparatus (100) incline causes apparatus (100) to take advantage of the gravity (negative offset) and helps adjust the apparatus (100) automatically. In the case of positive offset the apparatus (100) may climb up the step caused by positive offset. Since the apparatus (100) is of fixed length even at the bottom side (end plates 110B) the apparatus (100) adjusts automatically. At the bottom side we a leaf spring wheel system may be incorporated as explained in detail in Figure. 10.

Figure. 8A and 8B depicts an isometric view of a charging unit (180) having a rechargeable battery mounted on the apparatus (100), according to one embodiment of the present disclosure. Elements of Figure. 8A and 8B have been explained in conjunction with the elements of Figure. 1 to 7.

In one embodiment, the apparatus (100) includes a charging unit (180) having the a rechargeable battery and (as shown in Figure. 8A and 8B). The charging unit (180) is configured to charge the rechargeable battery of the apparatus (100). The charging unit (180) includes stationary charging panels which are solar panels intended for charging. The charging unit (180) is positioned on the same horizontal plane as of the main panels (PV panels). In one example, the charging unit (180) may be located at the resting position of the apparatus (100). The charging unit (180) may be placed at one end of the PV panels from where the apparatus (100) starts to move ahead on the surface of the PV panels, or may be placed at another end of the PV panels where the apparatus (100) stops. For example, the charging unit (180) depicted in Figure. 8A and 8B is mounted proximal to the end plate 110B.

Further, the charging unit (180) includes a plurality of plunger connector and actuator (182). The plurality of plunger connector and actuator (182) are configured to connect/latch the apparatus on to the stationary charging panel (power supplying panel) of the charging unit (180) for recharging. In one embodiment, the apparatus (100) includes two plunger connectors required to connect positive and negative terminals of the charging panels to the charging unit (180). The redundancy in the number of plunger connector and actuator (182) ensures that when docked, the battery of the apparatus (100) is charged via at least a pair of plunger connector and actuator (182). Further, the redundancy and orientation of the redundant plunger connector and actuator (182) minimizes effect of dust deposition does not impact the connectivity on the main pair of plunger connector and actuator (182). This ensures that there would always be a parallel connection available for the charging current to flow to the charging circuit.

In one embodiment, the plunger connector includes a spring mechanism that pushes the plunger toward a plate when the apparatus (100) traverses the actuator and closes the connection between each terminal of the charging panel to the charging unit (180). Then, the battery of the apparatus (100) starts charging.

Figure. 9 depicts an isometric view of the first support structure sub assembly (190) of the apparatus (100) and a first mechanism for altering the length of the apparatus (100), according to one embodiment of the present disclosure. Elements of Figure. 9 have been explained in conjunction with the elements of Figure. 1 to 8B. Specifically, Figure. 9 illustrates the first support structure sub assembly (190) and a plurality of notches (900) provided therein. Using the plurality of notches (900), length of the apparatus (100) is adjustable to vary the length and coverage area of cleaning of the apparatus (100).

Figure. 10 depicts an isometric view of the first support structure sub assembly (190) of the apparatus (100) and a second mechanism for altering the length of the apparatus (100), according to one embodiment of the present disclosure. Elements of Figure. 10 have been explained in conjunction with the elements of Figure. 1 to 9. Specifically, Figure. 10 illustrates the first support structure sub assembly (190) and a plurality of notches (1000) provided therein. In an embodiment, the plurality of notches (1000) may be located proximal to end plate 110A and/or 110B. Using the plurality of notches (900), length of the apparatus (100) is adjustable to vary the length and coverage area of cleaning of the apparatus (100). Additionally, the depicted embodiment further illustrates a safety pad (1005) to protect the PV panel from damage to weight of the apparatus (100).

As explained in Figure. 7, at the bottom side a leaf spring system (1010) may be incorporated to easily adjust the apparatus (100) and movement thereof, when horizontal offsets are encountered and the edge to edge distance between the panels varies in range. The leaf spring system (1010) may also help apparatus (100) not to wedge in case of such alignments and keeps the apparatus (100) always moving on the panel frame but not on the panel glass.

As a consequence of the plurality of side polyurethane (PU) wheels (200), a plurality of traction wheels (205), the plurality of bevel gears (210) and (215), provided at the top side (end plate 110A) of the apparatus (100) and the leaf spring side wheels at the bottom side (end plate 110B) of the apparatus (100), the apparatus (100) may move forward even in the case of horizontal (positive as well as negative) offsets in panel laying without getting stuck.

Further, in unlikely event of the apparatus (100) going cross on the panels when it encounters horizontal offsets that are more acceptable limits, there is a very likely chance of apparatus (100) wheels going out of the bounds and fall outside the panel frames. This situation may cause some of the metallic components of the apparatus (100) to hit and damage the panel glass, when it goes out of the panel frames. To arrest any damage may be arrested by the safety pads (1005) that are fitted lower than any other metallic component in the apparatus (100). Once the apparatus (100) goes out of the panel edges, these safety pads (1005) are the first ones that will come in contact with the panel glass and since they are made of rubber material, they will not cause any damage to the glass keeping the main panels safe from damage due to robot. There are two safety pads (1005) at both sides of the apparatus (100).

Figure. 11 depicts an isometric view of an apparatus locking system for controlling the movement of the apparatus (100), according to one embodiment of the present disclosure. Elements of Figure. 11 have been explained in conjunction with the elements of Figure. 1 to 10.

Specifically, Figure. 11 illustrates the apparatus (100) having a solenoid (not shown) based apparatus locking system (1100). The apparatus locking system (1100) when actuated, is configured to lift the lock (1105) and the apparatus (100) will be free to move forward. In any other event such as wind gusts the apparatus (100) may be locked at its docking position and may be prevented from moving forward due to wind forces.

Various embodiments of the disclosure encompass numerous advantages including an apparatus (100) for cleaning an array of photovoltaic (PV) panels that provides flexible brush assemblies that adjust automatically to the varying panel to panel vertical differences. The apparatus further leverages lever-based design and levers with bearing blocks, and pulleys and timing belts. As a result, the cleaning brushes are free to move along with the pulley in vertical axis to take care of the vertical offsets between panels. The apparatus further incorporates polyurethane damper rollers to absorb the shock that may result due to sudden vertical movement of the brush when it encounters a sizeable vertical offset. The proposed apparatus further provides a modified the actuator to provide for redundant actuators and redundant plunger connectors to ensure fail safe operation. The second set of actuator, plunger connector pair that are at a right angle to the main pair ensure minimal dust deposition and does not impact the connectivity on the main pair. This ensures that there would always be a parallel connection available for the charging current to flow to the charging circuit.

The present disclosure may be realized in hardware, or a combination of hardware and software. The present disclosure may be realized in a centralized fashion, in at least one computer system, or in a distributed fashion, where different elements may be spread across several interconnected computer systems. A computer system or other apparatus adapted for carrying out the methods described herein may be suited. A combination of hardware and software may be a general-purpose computer system with a computer program that, when loaded and executed, may control the computer system such that it carries out the methods described herein. The present disclosure may be realized in hardware that includes a portion of an integrated circuit that also performs other functions.

A person with ordinary skills in the art will appreciate that the systems, modules, and sub-modules have been illustrated and explained to serve as examples and should not be considered limiting in any manner. It will be further appreciated that the variants of the above disclosed system elements, modules, and other features and functions, or alternatives thereof, may be combined to create other different systems or applications.

Those skilled in the art will appreciate that any of the aforementioned steps and/or system modules may be suitably replaced, reordered, or removed, and additional steps and/or system modules may be inserted, depending on the needs of a particular application. In addition, the systems of the aforementioned embodiments may be implemented using a wide variety of suitable processes and system modules, and are not limited to any particular computer hardware, software, middleware, firmware, microcode, and the like. The claims can encompass embodiments for hardware and software, or a combination thereof.

While the present disclosure has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from its scope. Therefore, it is intended that the present disclosure not be limited to the particular embodiment disclosed, but that the present disclosure will include all embodiments falling within the scope of the appended claims.