FORM-2
THE PATENTS ACT, 1970
(39 of 1970)
COMPLETE SPECIFICATION
(Section 10, rule 13)
A SOLAR CONCENTRATOR
Thermax Limited
with Corporate office at Thermax House, 4 Pune-Mumbai Road,
Shivaj inagar, Pune
411005, Maharashtra, India.
an Indian Company registered under the provisions of the Companies Act, 1956,
The following specification particularly describes the invention and the manner in which it is to be performed: -
FIELD OF THE INVENTION:
This invention relates to solar concentrator
Further this invention relates to solar concentrator with a tracking mechanism. More particularly, this invention relates to solar concentrator with tracking mechanism to improve overall efficiency.
BACKGROUND OF THE INVENTION:
Increasing awareness to switch from conventional energy resources for harnessing power for daily and industrial use to non-conventional energy sources is on the upswing, with countries assembling to fight global warming, greenhouse emissions, and the like. One such abundant source of non-conventional energy source is solar energy.
Solar concentrators are typically employed for concentration of solar radiation for generation of higher flux or temperature to convert to useful heat or electrical energy For continuous concentrated irradiation, the solar reflector must be aligned with the direction of the sun in the sky with respect to the position of the solar reflector on earth. For this, parabolic reflectors and tracking mechanism are employed.
In parabolic reflectors, a focus can be defined, wherein incoming rays of light which are parallel to the axis of the parabola are incident at the focus, thus increasing the concentration of radiations upon a given surface, and thus allowing use of solar energy for home heating, power generation or industrial purposes.
Tracking mechanisms for parabolic reflectors ensure that the radiant light of sun is always focused to achieve maximum energy concentration, by way of aligning the solar reflector's position in synchronism with the position of the sun in the sky.
PRIOR ART:
US patent no. 4149523 relates to a system for concentrating solar energy. The system provided parabolic cylinder forming mirror wherein the direction of the sun lying in its symmetry plane. The said mirror has a parabolic cross-section, a very large aperture relative to the diameter of the tube at its focal point characterized by a sealed chamber formed by transparent and the flat surfaces insulating the receiving tube and the mirror from the surrounding atmosphere.
US patent nos. 4568156 and 4616909 describe bowl shaped reflectors, reflector members with tracking system of high stability and minimum maintenance.
US patent no. 4632091 describes solar apparatus and solar energy collecting method wherein the apparatus uses electrical motor for rotating a reflector supported by a frame around a stationary conduit to track the sun rays controlled by light sensor.
US patent no. 4784700 discloses a focus point solar concentrator wherein cylindrical strips of various geometries, some of the strips are tilted to simulate point focus by overlaying the line of foci of each segment at a coincident point. Further its use in a combo photovoltaic / solar engine concentrator energy system is also disclosed.
US patent no. 5347402 describes a light weight mirror assembly for solar collector wherein said assembly concentrates solar rays having rows and columns of individual rectangular mirrors mounted by means of flexible cords passing through eyelets on the edges of each of the mirrors, with the cords secured to an open rectangular frame.
US patent no. 5851309 describes concentrating solar energy collectors protected with a transparent cover concentrating reflector is a cylindrical parabolic reflector, said reflector is fresnel reflector, of rotating kind around the stationary line of concentration and a method of collecting solar energy.
US patent no, 6406155 discloses a parabolic reflector assembly useful in solar energy concentrators in solar apparatus and also in other applications and manufacturing method of parabolic reflectors. The reflector assembly has a base member of magnetic material, a flexible magnet sheet on inside and outside of parabolic surface magnetically bonded to base member.
US patent no. 6818818 describes a solar energy receiver comprising a parabolic reflector of primary and secondary kind wherein the primary configuration has a principal axis and a center and a reflective surface, a supporting frame, a motor driving assembly and conversion module to convert solar energy to electric energy.
US patent no. 7014329 discloses a foldable solar reflector. The parabolic reflector is formed from a flat circular disk assembly with overlapping spiral side segments and a flat circular base or fit together along a seam without overlapping.
US patent no. 7240675 describes a parabolic trough collector that has optical behavior efficiency in non-active areas. The said collector is composed of receiver formed from number of absorber tubes, each single tube supported absorber tube support and surrounded by a glass tube, said arrangement receives radiation from non active area where mirror collar as secondary reflector absorbs reflecting solar radiation coming from different directions and also when sun incident angle changes. The parabolic reflector mounted on a reflector support having focus line connected with individual absorber tubes at the focus line and the flexible unions help compensate the heat expansion between the steal of the absorber tube and the glass tube.
US patent no. 7569764 discloses fixed solar electric module and the tracking mechanism. The module is composed of at least four concentrator assemblies, each assembly pivotably mounted on same plane comprising photovoltaic or thermoelectric receiver with one or more optical reflectors or lenses to concentrate reflected sunlight.
US patent application no. 20080308094 relates to trough reflectors which are used to concentrate solar energy, and solar energy collectors wherein a simple and effective method of applying an edge correction is described.
US patent application no. 20080127967 describes solar energy collector and method for concentrating solar radiation, wherein said solar energy collector comprising housing comprising a first panel and a second panel; a first bracket connecting the first panel and the second panel; a heat collector; and a first reflector positioned within said enclosure to receive solar radiation and concentrate at least a portion of said solar radiation on said heat collector. The kind of solar collectors suited for use in tropical and coastal applications, where environmental conditions may promote corrosion, as well as in desert applications where sand, dust, or grit may otherwise abrade unprotected components.
WO patent application no. 2008153936 relates to a solar energy collector array and solar collector assembly wherein the array comprising a plurality of rows of solar energy collectors having a first deflector adjacent to a first row of the solar energy collectors and a second deflector adjacent to a second row of the solar energy collectors and a solar collector movable from a first light-collecting position to a second parked position in which a light collecting surface of the solar collector faces toward earth, rotatable about an axis through supports of said solar collector, or pivotable about a pivot point of said solar collector, and wind deflector positioned closer to a side of the solar collector to protect from wind-borne debris when the solar collector is in parked position.
US patent application no. 20090056704 relates to reflection parabolic construction for solar heating systems. The said construction includes a reflecting parabola for concentrating solar beams on a receiver tube containing a thermal carrier fluid therein, characterized in that said parabola comprises a central aluminum fretted layer having opposite faces on each of which is applied a respective aluminum reflecting layer, said parabola having a parabola concave portion coated by a thin crystal mirror.
US patent application no. 20090211569 relates to an improved reflector for a solar collector wherein said reflector is with appropriate optical properties, resistant without a frame member to maintain its curved shape. Further it provides an efficient method manufacturing the reflector that is cheap, simple and reproducible.
US patent application no. 20090223510 describes a solar collector for concentrating solar radiation, said parabolic collector is formed from a plurality of sections flexibly connected through a hinge arrangement attached on a line tangent with the trough axis allowing the reflective surfaces to position forming a continuous parabolic surface in a first position, while also being positionable in other positions.
US patent application no. 20090235985 relates to concentrators for solar photovoltaic power generation systems and solar thermal power generation systems that include a plurality of concentrating regions. Further the invention also relates to a method of manufacturing a light collection system.
The parabolic reflectors and the tracking mechanism disclosed in the prior art with different objectives for different purposes have limitations with climatic conditions or for their application in specific area for specific purposes.
There is a need for an efficient parabolic solar reflector with a tracking mechanism. OBJECTS OF THE INVENTION:
An object of this invention is to provide a solar concentrator apparatus that is cost effective
Another object of this invention is to provide a solar concentration apparatus with a parabolic solar reflector, said reflector is cost efficient.
Further object of this invention is to provide multiple members for the functioning of the apparatus.
Yet another object is to provide a solar reflector with tracking mechanism.
Still further object of this invention is to provide solar apparatus with improved efficiency.
SUMMARY OF THE INVENTION:
The present invention describes a solar concentrator apparatus with solar reflector and a plurality of functional members.
It is envisaged that solar reflector with an efficient gear tracking mechanism to improve efficiency of the solar apparatus.
According to this invention, there is provided a solar collector apparatus with a cost efficient parabolic reflector, said apparatus comprises:
solar collector for collecting rays of sunlight for concentration purposes;
parabolic reflector frame for said solar collector adapted for increased concentration of collection of rays of sunlight, said parabolic frame including a top square frame supported by parabolic profile sections to form a Pi shaped parabolic member;
mirror for reflecting said rays of sunlight, said mirror being curved parabolically to align with operative inner side of said parabolic profile section;
trough member adapted to hold said solar collector and parabolic frame; and
tracking gear mechanism adapted to rotate the trough member in synchronism with sun's movement such that the fixed focus parabolic collector is tracked by rotating around the focus having diameter equal to trough width.
Typically, a plurality of apparatus is connected in a row and column format.
Typically, said parabolic reflector frame is made of multiple parabolic Pi members.
Typically, said solar reflector comprises a top frame supported by a perpendicular frame member with a cross frame member for adequate stability against wind load .
Alternatively, said solar reflector comprises a top frame supported by an angular frame member with a cross frame member.
Still alternatively, said solar reflector comprises a top frame supported by a rectangular frame member with a cross frame member.
Typically, said mirror is fixed for said parabolic reflector frame by means of a mirror fixing mechanism comprising a backup sheet to continuously support a flexible mirror sheet and to provide a parabolic reflective surface.
Typically, said tracking gear mechanism comprises a gear pair.
Typically, said tracking gear mechanism comprises a large tracking gear, a small tracking gear, a trough shaft, and a drive shaft adapted to be driven by a drive motor.
Typically, a plurality of tracking gear mechanisms is connected to drive a plurality of solar reflectors respectively.
Typically, drive couplings are engaged to couple one tracking gear mechanism to its adjacent tracking gear mechanism.
Alternatively, said tracking gear mechanism is a twin pair gear mechanism with two large tracking gears and two corresponding small tracking gears.
Still alternatively, said tracking gear mechanism is a multiple pair drive gear mechanism with pairs of large tracking gears and small tracking gears.
Typically, an absorber tube is adapted to absorb solar radiations incident on solar reflector._
Typically, a glass covering receiver tube is adapted to cover said solar reflector to reduce heat loss.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
The invention will now be described in relation to the accompanying drawings, in which:
Figure 1 of the accompanying drawings illustrates solar parabolic collector;
Figure 2 of the accompanying drawings illustrates view of rows and columns of solar parabolic collector;
Figure 3 of the accompanying drawings illustrates details of parabolic member;
Figure 3a of the accompanying drawings illustrates sectional view of (Pi) section of parabolic member;
Figure 4 of the accompanying drawings illustrates multiple parabolic (Pi) section;
Figure 5 of the accompanying drawings illustrates mirror fixing device;
Figure 5a of the accompanying drawings illustrates mirror fixing sandwich mechanism;
Figure 6a of the accompanying drawings illustrates perpendicular frame of solar collector;
Figure 6b of the accompanying drawings illustrates angular frame of solar collector;
Figure 6c of the accompanying drawings illustrates rectangular frame of solar collector;
Figure 7 of the accompanying drawings illustrates trough gear tracking mechanism;
Figure 7a of the accompanying drawings illustrates cut view of trough gear tracking mechanism;
Figure 8a of the accompanying drawings illustrates single pair multiple drive gear mechanism;
Figure 8b of the accompanying drawings illustrates twin pair multiple drive gear mechanism;
Figure 8c of the accompanying drawings illustrates multiple pair multiple drive gear mechanism; and
Figure 9 of the accompanying drawings illustrates absorber and glass cover tube.
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
Figure 1 of the accompanying drawings illustrates solar parabolic collector in accordance with this invention.
According to this invention, there is provided a solar collector apparatus with a parabolic reflector, said apparatus comprises solar collector for collecting rays of sunlight for concentration purposes; parabolic reflector frame (2,3) for said solar collector adapted for increased concentration of collection of rays of sunlight, said parabolic frame (2,3) including a top frame (1 & la) supported by two parabolic profile sections to form a Pi shaped parabolic member (3); mirror (7) for reflecting
said rays of sunlight, said mirror (7) being curved parabolically to align with operative inner side of said parabolic profile section (3); trough support (26) adapted to hold said solar collector (I) and parabolic frame (2,3); and tracking gear mechanism (15, 16) adapted to rotate the trough over fixed support (26) in synchronism with sun's movement such that the fixed focus parabolic collector is tracked by rotating around the focus having diameter equal to trough (26) width. 17 refers to drive shaft. 23 refers to glass tube covering. 22 refers to absorber tube. 21 refers to trough shaft and 26 refers to trough support.
Typically, a plurality of solar parabolic collector apparatus is connected in a row and column format, as shown in Figure 2 of the accompanying drawings.
Figure 3 of the accompanying drawings illustrates a side-view of parabolic member wherein, a rectangular frame (1) is seen. This frame is connected to a parabolic member (2). A profile A'-A' of the parabolic member (2) of Figure 3 is seen in Figure - 3a of the accompanying drawings. This shows a parabolic Pi section which consists of parabolic member (4) and fiat plate (3) with holes (3A), to make a Pi section as illustrated .Reference numeral 5 illustrates weld position for parabolic member to the top plate to make a Pi member.
Figure 4 of the accompanying drawings illustrates multiple parabolic (Pi) sections, in accordance with another embodiment of this invention. A frame (1) for a solar parabolic collector and the parabolic Pi members (2) are illustrated therein.
Figure 5 of the accompanying drawings illustrates mirror fixed onto the apparatus. Typically, said mirror (7) is fixed for said parabolic reflector frame by means of a mirror fixing mechanism (as illustrated in Figure 5a of the accompanying drawings) comprising a backup sheet (6) to continuously support a flexible mirror sheet (7) and to provide a parabolic reflective surface (2). A cut-view along B'-B' of Figure 5 showing the mirror fixing sandwich mechanism is shown in Figure 5a of the accompanying drawings. The mirror (7) and mirror back up support (6) is bound together at their ends with supporting plates (8) with hole (8A) to receive the nut-bolt (10) and washer (9) fixing mechanism. Further, the lower opposite side of the plate is a parabolic Pi member (3A) with parabolic members (2).
Typically, said solar reflector comprises a top frame (I & la) supported by a perpendicular frame member (12) with a cross frame member (11), as shown in Figure 6 of the accompanying drawings.
Alternatively, said solar reflector comprises a top frame (la) supported by an angular frame member (13) with a cross frame member (11) as shown in Figure 6b of the accompanying drawings.
Still alternatively, said solar reflector comprises a top frame (la) supported by a rectangular frame member (14) with a cross frame member (11) as shown in Figure 6c of the accompanying drawings.
Figure 7 of the accompanying drawings illustrates trough gear tracking mechanism. The rectangular frame (1 & la) along with parabolic member (2) of the apparatus engages with the gear tracking mechanism, for movement of tracking the sun. The gear tracking mechanism includes, a small tracking gear (16) adapted to work along with a large tracking gear (15). A trough shaft (21) and a drive shaft (17) are provided, too for movement.
Figure 7a of the accompanying drawings illustrates a cut-view of Figure 7 along A-A. The gear pair for tracking can be seen. The apparatus along with frame (1), cross frame member (11), parabolic member (2) are driven by the gear tracking mechanism which includes, large tracking gear (15), small tracking gear (16), drive shaft (17), drive motor (18), trough shaft (21). Drive coupling (19) and adjacent trough drive shaft (20) are employed for connecting one solar collector apparatus with another, in a row or column.
Typically, said tracking gear mechanism is a multiple drive gear mechanism with a large tracking gear (15) and a small tracking gear (16) as shown in Figure 8a of the accompanying drawings. The trough shaft (21), rectangular frame (1), cross frame member (11), and drive shaft (17) are shown.
Alternatively, said tracking gear mechanism is a twin pair gear mechanism with two large tracking gears (15) and two small tracking gears (16) as shown in Figure 8b of the accompanying drawings. The trough shaft (21), rectangular frame (1), cross frame member (11), and drive shaft (17) are shown.
Still alternatively, said tracking gear mechanism is a multiple pair drive gear mechanism with pairs of large tracking gears (15) and small tracking gears (16) as
shown in Figure 8c of the accompanying drawings. The trough shaft (21), rectangular frame (1), cross frame member (11), and drive shaft (17) are shown.
Figure 9 of the accompanying drawings illustrates absorber and glass cover tube. Typically, an absorber tube (22) is adapted to absorb solar radiations incident on solar reflector. Typically, a glass covering receiver tube (23) is adapted to cover said solar reflector to reduce heat loss. Numeral (24) refers to Bush between glass tube and trough shaft, Numeral (25) refers to Bush between glass tube and absorber tube
While considerable emphasis has been placed herein on the specific elements of the preferred embodiment, it will be appreciated that many alterations can be made and that many modifications can be made in the preferred embodiment without departing from the principles of the invention. These and other changes in the preferred embodiment as well as other embodiments of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.
We claim,
1. A solar collector apparatus with a parabolic reflector, said apparatus comprising:
solar collector for collecting rays of sunlight for concentration purposes;
parabolic reflector frame for said solar collector adapted for increased concentration of collection of rays of sunlight, said parabolic frame including a top and cross frame supported by two parabolic profile sections to form a Pi shaped parabolic member;
mirror for reflecting said rays of sunlight, said mirror being curved parabolically to align with operative inner side of said parabolic profile section;
trough member adapted to hold said solar collector and parabolic frame; and
tracking gear mechanism adapted to rotate the trough in synchronism with sun's movement such that the fixed focus parabolic collector is tracked by rotating around the focus having diameter equal to trough width.
2. An apparatus as claimed in claim 1 wherein, a plurality of apparatus is connected in a row and column format.
3. An apparatus as claimed in claim 1 wherein, said parabolic reflector frame is made of multiple parabolic Pi members.
4. An apparatus as claimed in claim 1 wherein, said solar reflector comprises a top frame supported by a parallel Pi frame member with a cross frame member.
5. An apparatus as claimed in claim 1 wherein, said solar reflector comprises a top frame supported by an angular frame member with a cross frame member.
6. An apparatus as claimed in claim 1 wherein, said solar reflector comprises a top frame supported by a rectangular frame member with a cross frame member.
7. An apparatus as claimed in claim 1 wherein, said mirror is fixed for said parabolic reflector frame by means of a mirror fixing mechanism comprising a backup sheet to continuously support a flexible mirror sheet and to provide a parabolic reflective surface.
8. An apparatus as claimed in claim 1 wherein, said tracking gear mechanism comprises a gear pair.
9. An apparatus as claimed in claim 1 wherein, said tracking gear mechanism comprises a large tracking gear, a small tracking gear, a trough shaft, and a drive shaft adapted to be driven by a drive motor.
10. An apparatus as claimed in claim 1 wherein, a plurality of tracking gear mechanisms is connected to drive a plurality of solar reflectors respectively.
11. An apparatus as claimed in claim 1 wherein, drive couplings are engaged to couple one tracking gear mechanism to its adjacent tracking gear mechanism.
12. An apparatus as claimed in claim 1 wherein, said tracking gear mechanism is a multiple drive gear mechanism with a large tracking gear and a small tracking gear.
13. An apparatus as claimed in claim 1 wherein, said tracking gear mechanism is a twin pair gear mechanism with two large tracking gears and two small tracking gears.
14. An apparatus as claimed in claim 1 wherein, said tracking gear mechanism is a multiple pair drive gear mechanism with pairs of large tracking gears and small tracking gears.
15. An apparatus as claimed in claim 1 wherein, an absorber tube is adapted to absorb solar radiations incident on solar reflector.
16. An apparatus as claimed in claim 1 wherein, a glass covering receiver tube is adapted to cover said solar reflector to reduce heat loss.