Directed reflection light collecting device with planar reflectors

This invention relates to a directed reflection light collecting device with planar reflectors, wherein a number of planar reflectors are arranged on a frame in mutual parallel. This frame is rotatably supported via a transversal main turning shaft on the supports of an azimuth angle adjusting mechanism. The altitudinal angle adjusting mechanism drives the frame in a controlled manner causing the planar reflectors on it to move. In this invention, the altitudinal angle of a number of planar reflectors is synchronized via a simple frame structure so that they can always project the reflected sunlight in a substantially fixed direction into the given area in conjunction with the azimuth angle adjusting mechanism.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority from Chinese Patent Application No. 03152803.1, entitled “Directed Reflection Light Collecting Device with Planar Reflectors,” filed on Aug. 21, 2003.

FIELD OF THE INVENTION

This invention relates to a natural light collecting and lighting device that utilizes solar energy, in particular a directed reflection light collecting device with planar reflectors.

BACKGROUND OF THE INVENTION

Continuous world population growth and sustained development of the global economy has given rise to a rapid increase in the demand for lighting. Lighting is one of the most energy-consuming demands, as most people in developed or developing countries work and live in rooms with artificial lighting. However, the peak demand for indoor lighting takes place in the daytime when there is abundant sunlight. 40% of power for lighting is consumed during this time period. Therefore, development and utilization of inexhaustible solar energy resources can be of great value to energy-savings. Such savings can, in turn, greatly reduce the CO2discharge from power plants, resulting in a better ecological environment and paving a strategic route to sustainable economic development.

Furthermore, as land resources become more expensive in modern society, residential houses are generally designed in an architectural layout that maximizes exterior wall exposure to sunlight in an effort to meet the lighting requirements of residents. In many large public buildings, for instance shopping malls, large, open architectural areas (referred to as skylights) are designed, which render precious space useless. Even so, such large buildings remain mainly dependant on artificial lighting. To minimize waste of space resources and obtain good natural lighting, people have been exploring various light collecting technologies with the potential to maximize the natural light environment

For more than two decades, the technology to harness sunlight for interior lighting has been a focus of research in many countries. This technology can be roughly grouped into three types: light transmission with light pipes, light transmission with optical fibers and direct reflection lighting with planar reflectors, such as the prismatic light pipes produced by the 3M Company of Minneapolis, Minn., and the optical fibers light collector Himawari system made in Japan. Although such media as light pipes and optical fibers have some superiority in light transmission, they are expensive and it is difficult to apply them in practical ways.

Direct reflection lighting with planar reflectors is an economic and practical way to harness light with a reasonable performance to price ratio. The planar reflectors are installed on the tops of buildings, allowing the interiors direct access to reflected sunlight; secondary reflectors can be installed to further reflect light into rooms. For instance, in U.S. Pat. Nos. 4,883,340, 4,586,488 and 4,922,088, light is obtained by reflecting sunlight using planar reflectors. In U.S. Pat. No. 4,883,340, a number of parallel planar reflectors are fixed on supports. At the lower end of the supports, an azimuth angle adjustment mechanism controls the azimuth angle of the planar reflectors. However, as the altitudinal angle of the sun changes continuously throughout the day, the direction of the sunlight reflected by planar reflectors also changes. As a result, the projection of light from this light collection device moves continuously with the change of the sun's altitudinal angle, making it impossible to get light in a fixed direction. Furthermore, in this patent, the spacing of planar reflectors is fixed, thus, there may be unlighted spaces between the projections of reflected light from the planar reflectors at higher sun altitudinal angles, and overlapping may occur at lower altitudinal angles To avoid such overlapping, the planar reflectors need to be more widely spaced, which results in an oversized installation and wasted space. Both devices in U.S. Pat. Nos. 4,586,488 and U.S. Pat. No. 4,922,088 have realized reflection in a fixed direction, but due to structural defect, two planar reflectors can only be arranged on separate sides of the turning shaft, leaving an unlighted space in the reflected light projection.

SUMMARY OF THE INVENTION

This invention is primarily aimed at providing a directed reflection light collecting device with planar reflectors for lighting a given area with sunlight projection. In this invention, the altitudinal angle of a number of planar reflectors can be adjusted in a synchronized manner by means of a simple frame structure so that the reflected sunlight is always projected in a substantially fixed direction into the given area in conjunction with the azimuth angle adjusting mechanism.

This invention is also aimed at providing a directed reflection light collecting device with planar reflectors, in which the spacing between the planar reflectors can be adjusted in conjunction with the altitudinal angle adjustment of these planar reflectors so as to make maximum use of the area of each planar reflector to reflect the sunlight.

This invention is also aimed at providing a directed reflection light collecting device with planar reflectors, which can ensure basically no overlapping or unlighted space for the reflected light projection of all planar reflectors in the given area to realize the purpose of sufficient utilization of sunlight for sufficient lighting and even heating.

The above objectives of this invention can be realized with the following technical scheme: a directed reflection light collecting device with planar reflectors, comprising two or more planar reflectors; an azimuth angle adjusting mechanism and an altitudinal angle adjusting mechanism of the planar reflectors; the azimuth angle adjusting mechanism including a base, supports, a circular rail with central axial line ZZ′; and a driving mechanism, wherein, the two or more planar reflectors are arranged in mutual parallel on a frame; the altitudinal angle adjusting mechanism including at least one transversal main turning shaft parallel with the planar reflectors; the frame being rotatably supported via this transversal main turning shaft on the supports of the azimuth angle adjusting mechanism; the altitudinal angle adjusting mechanism driving this frame in a controlled way to enable movement of planar reflectors on it; the altitudinal changing angle of these planar reflectors being half of the sun altitudinal changing angle.

In this way, this invention, with its altitudinal angle adjusting mechanism and azimuth angle adjusting mechanism, can adjust the altitudinal angle and azimuth angle of the planar reflectors in conjunction with the change of sunlight direction so that the sunlight reflected by the planar reflectors is projected in a substantially fixed direction into the given area, enabling this given area to receive sunlight all day long. Moreover, this invention features a structure combining a number of parallel planar reflectors within the same frame. Therefore, the altitudinal angle adjusting mechanism can realize altitudinal angle adjustment of a number of planar reflectors on the frame simply by moving this frame. Compared with the previous technology which requires separate adjustment of each planar reflector, it is obvious that the structure has been greatly simplified, and the equipment manufacturing cost lowered.

In one embodiment, the frame of this invention can be in an integral rigid structure, with planar reflectors fixed on it at certain spacing in parallel, and the transversal main turning shaft in rigid connection with the frame, the altitudinal angle adjusting mechanism driving the transversal main turning shaft to rotate in a controlled way to rotate the whole rigid frame, thereby adjusting the altitudinal angle of the planar reflectors on it in a synchronized manner.

In another embodiment of this invention, the frame of this invention can be a parallel four-connecting-rod mechanism, on the two parallel connecting rods along the length of this parallel four-connecting-rod mechanism can be hinged with two or more parallel connecting rods in height direction, the planar reflectors are respectively fixed on all parallel connecting rods moving in synchronization of this parallel connecting rod mechanism in height direction to adjust the altitudinal angle of planar reflectors and their mutual spacing with the movement of the parallel connecting rod mechanism.

The parallel connecting rod mechanism is not only simple in structure with good technical performance, the corresponding connecting rods can remain parallel at all times, therefore, when the planar reflectors are respectively fixed on the connecting rods in parallel movement, all planar reflectors can move in a parallel track as long as one rod is driven. In the movement of parallel connecting rods, not only the altitudinal angle of planar reflectors is adjusted, but also the vertical distance between adjacent planar reflectors, or spacing, is adjusted concurrently by changing the angle between adjacent connecting rods. This enables the spacing of a number of parallel planar reflectors to change in conjunction with the change in the sun altitudinal angle, ensuring maximum use of the area of each planar reflector to reflect the sunlight.

Furthermore, in this invention, the planar reflectors are in rectangular shape, and in this multiple parallel planar reflector assembly, the connecting lines of four apexes of every two adjacent planar reflectors on the same side form a rhombus, in which one of the diagonal lines is always parallel with the central axial line ZZ′ of the circular rail.

In this way, the projection of sunlight reflected by each planar reflector just joins together and remains so all the time. This ensures that the reflected light projection of all planar reflectors in the given area is basically free of overlapping or unlighted space and can avoid possible unlighted space between the projections of planar reflectors or blocking of reflectors as in the case of some existing technologies to accomplish full utilization of sunlight for sufficient lighting and even heating.

To ensure that one of the diagonal lines remains parallel with the central axial line ZZ′ of the circular rail during the movement of the parallel connecting rod mechanism, the power for driving the parallel connecting rod mechanism can be a reciprocating linear moving mechanism, which forms the altitudinal angle adjusting mechanism together with the transversal main turning shaft. The reciprocating linear moving mechanism is connected to one of the connecting rods of the parallel connecting rod mechanism via its moving part. The moving line of this part is parallel with one diagonal line of the rhombus. The linear movement of the moving part of reciprocating linear moving mechanism pushes the movement of the parallel connecting rod mechanism to adjust the altitudinal angle and spacing of planar reflectors.

In another embodiment, the power for driving the parallel connecting rod mechanism can also be from the transversal main turning shaft connected with the altitudinal angle motor driving mechanism. In this case, the parallel connecting rod mechanism is in rigid connection with the transversal main turning shaft via a connecting rod. A straight line passing this rigid connection point and parallel with one diagonal line of the rhombus intersects the adjacent connecting rod at another point, where a sliding block or pulley is provided and can slide along a straight sliding trough mounted between the rigid connection point and the intersecting point. The transversal main turning shaft is connected with the driving motor (including a reducer) of the altitudinal angle adjusting mechanism at one end.

The azimuth angle adjusting mechanism in this invention can include a base, supports, a circular rail with central axial line ZZ′ and a driving mechanism. The driving mechanism drives the supports so that the planar reflectors on the frame can rotate around the central axial line ZZ′ of the circular rail to adjust its azimuth angle. The azimuth changing angle of planar reflectors is equal to the sun azimuth changing angle.

In this mechanism, the driving mechanism for adjusting the azimuth angle comprises a motor (including a reducer) and friction wheels connected at the motor (including a reducer) output end. The driving mechanism is fixed on the supports bottom, and the rail is in rigid integration with the base. The friction wheels are in contact with the rail to drive the supports to rotate around the axial line ZZ′ along the rail.

In another embodiment, the driving mechanism for azimuth angle adjustment can comprise a motor (including a reducer) and friction wheels connected at the motor (including a reducer) output end. The driving mechanism is fixed on the base, the rail is in rigid connection with the supports and is rotatably supported on the base via rollers or balls fixed on the base. The friction wheels are in contact with the rail to drive the rail itself together with the supports to rotate.

With both ways of implementing azimuth angle adjustment as described above, the sunlight can be eventually projected in the direction of the central axial line ZZ′ of the circular rail. When the central axial line ZZ′ of the circular rail is perpendicular to the horizontal plane, or the set sunlight projecting direction is perpendicular to the horizontal plane, there is no overlapping or unlighted space between projected light from the planar reflectors so the area of each reflector is fully utilized.

Furthermore to enable the sunlight reflected by the light collecting device to be projected in a substantially fixed direction other than the central axial line ZZ′ of the circular rail, the azimuth changing angle of the frame rotating around the central axial line ZZ′, the planar reflectors on the frame and the supports for the frame should be half of the sun azimuth changing angle so that by selecting proper initial conditions, planar reflectors will be able to project the sunlight to other fixed location.

To monitor the sun position for tracking purpose, two types of sensors have been proposed in this invention to monitor the sun position and in fairly simple structure. One of them is comprised of a light shading post, photosensitive elements arranged in four directions around the post, and a base for burying the photosensitive elements at a certain depth. For each photosensitive element, a reflection shading block is arranged above the ⅙–½ of receiving window close to the light shading post side wall. Another sensor is formed by a cylindrical barrel, large lens, four small lenses and four photosensitive elements corresponding to the four small lenses. The large lens is located at the most front of the cylindrical barrel, the four small lenses in the middle of the barrel and the four photosensitive elements at the rear end of the barrel. The output ends of the photosensitive elements are connected to the processing circuit. For the specific principle of application of sensors and processing circuit, references is made to U.S. Pat. No. 6,465,766B1.

The planar reflectors in this invention can be glass mirrors, or flat plates with high-efficiency light reflecting films applied onto their surfaces.

By means of the two-dimensional adjusting mechanisms for azimuth angle and altitudinal angle and under the control of sensor and processing circuit, the above mentioned light collecting device performs the function of solar automatic tracking, and the planar reflectors project the sunlight in a substantially fixed direction at all times. Also, the planar reflectors and altitudinal angle adjusting mechanism can be mounted symmetrically above the given area via the transversal main turning shaft, without the need to install them with a cantilever on one side of the transversal main turning shaft of altitudinal angle adjusting mechanism, nor eccentrically to the rotating shaft of the azimuth angle adjusting mechanism, making the driving easier. The whole light collecting device of this invention features compact structure, simple arrangement, good balance and low cost.

It can be seen that the frame structure and the multiple planar reflectors mounted on it in this invention are driven by the reciprocating linear moving mechanism or the transversal main turning shaft connected with the altitudinal angle motor driving mechanism, for synchronized adjustment of planar reflectors altitudinal angle and spacing, and they automatically track the sun continuously by means of the rail type azimuth angle adjusting mechanism, thereby reflecting sunlight in a substantially fixed direction into a given area. The whole device takes the minimum possible space resources and has discarded forms of excessive complexity, thus both balance performance and movement performance have been improved. The device also lays an ideal foundation for the spreading of applications of directed reflection light collecting device with planar reflectors.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

As shown inFIGS. 1–6B, a directed reflection light collecting device with planar reflectors in this invention comprises two or more planar reflectors1, an azimuth angle adjusting mechanism2and an altitudinal angle adjusting mechanism3of the planar reflectors, the azimuth angle adjusting mechanism2includes a base, supports, a circular rail with central axial line ZZ′ and a driving mechanism. The two or more planar reflectors1are set parallel to each other on a frame4. The altitudinal angle adjusting mechanism3includes at least one transversal main turning shaft31parallel with the planar reflectors1. The frame4is rotatably supported via this transversal main turning shaft31on the supports21of the azimuth angle adjusting mechanism2, and the altitudinal angle adjusting mechanism3drives this frame4in a controlled manner to enable movement of the planar reflectors1. The altitudinal changing angle of the planar reflectors1is half of the sun altitudinal changing angle. The reason for this will now be described.

With the sun altitudinal angle continuously changing, the inclining angle of the planar reflectors should also be continuously adjusted to enable projection of sunlight in a substantially fixed direction after reflection by planar reflectors1. It is known from basic knowledge of geometric optics that the changing angle of the planar reflectors inclining angle should always be half of the sun altitudinal changing angle. This basic principle is clearly shown inFIG. 5, and should be applied in controlling the rotation of planar reflectors by detecting the sun position.

In this way, with the adjustment of the frame4by the altitudinal angle adjusting mechanism3and azimuth angle adjusting mechanism2, the altitudinal angle and azimuth angle of a number of planar reflectors on the frame4can change with the change in the altitudinal angle and azimuth angle of the sun so that the sunlight reflected by planar reflectors1is projected into the given area in a substantially fixed direction, and sunlight is received in this given area all day long. Furthermore, as a structure combining multiple parallel planar reflectors1and frame4is adopted in this invention, the altitudinal angle adjusting mechanism3can achieve the altitudinal angle adjustment of multiple planar reflectors1on the frame4by adjustment of the frame4. This has greatly simplified the structure and lowered the equipment manufacture cost as compared with the technology of making separate adjustment of each of the planar reflectors1.

As shown inFIGS. 1 and 2, the frame4in this invention is a parallel four-connecting-rod mechanism, in which two parallel connecting rods41and42along the length can be hinged with two or more parallel connecting rods43in height direction. The planar reflectors1are respectively fixed on the parallel connecting rods43moving in synchronization in the height direction with the parallel connecting rod mechanism to enable adjustment of the altitudinal angle and mutual spacing of planar reflectors1with the movement of the parallel connecting rod mechanism.

The parallel connecting rod mechanism is not only simple in structure with good technical performance, the corresponding connecting rods can remain parallel at all times. Therefore, when the planar reflectors1are respectively fixed on the connecting rods in parallel movement, all planar reflectors1can move in a parallel track as long as one rod is driven. In the movement of parallel connecting rods, not only the altitudinal angle of the planar reflectors1is adjusted, but also the vertical distance between adjacent planar reflectors1, or spacing, is adjusted concurrently by changing the angle between adjacent connecting rods. This enables the spacing of a number of parallel planar reflectors1to change with the change in the sun altitudinal angle to thereby maximize the area of each planar reflector to reflect sunlight.

As shown inFIGS. 2 and 3, in this embodiment, the power for each parallel connecting rod mechanism can be from a reciprocating linear moving mechanism33, which can form the above altitudinal angle adjusting mechanism with the transversal main turning shaft31. The reciprocating linear moving mechanism33can be a screw-nut mechanism, fitted between the transversal main turning shaft31(hinged supporting point O) and pin15at point O′ of the connecting rod A′F′E′. The screw12is connected at one end with the transversal main turning shaft31via a conical gear pair14and14′, and the nut13at the other end is hinge supported with pin15at point O′ of the connecting rod A′F′E′. The straight line for movement of nut13is parallel with the diagonal line A′C′ (or F′D′), and intersects the axial line of transversal main turning shaft31. The rotating movement of screw12is converted to the reciprocating linear movement of nut13, and pin15hinged with nut13follows the linear movement of nut13. In this way, the motor driving mechanism32can rotate screw12so that the nut13can move with the connecting rod A′F′E′ to enable change in the angle between connecting rods of the parallel connecting rod mechanism, and further make the planar reflectors1move to adjust the altitudinal angle and mutual spacing of the planar reflectors1.

As shown inFIGS. 2 and 4, the azimuth angle adjusting mechanism2mainly comprises a base22, supports21, a circular rail23with central axial line ZZ′ and its motor driving mechanism24for azimuth angle adjustment. The motor driving mechanism24is comprised of motor and reducer241and friction wheels242etc. Friction wheels242are in rigid connection on the output shaft of reducer241, the bottom of rail23set around the area ABCD is supported on three rollers25(only one of them is shown inFIG. 2), which are mounted respectively at locations I—I, II—II and III—III as shown inFIG. 4. These three rollers25and the motor driving mechanism24are all mounted on the base22, rail23is in rigid connection with supports21and is supported on base22via the three rollers25, friction wheels242are in contact with rail23to drive the rail itself to rotate together with the supports21around the central axial line ZZ′. In the diagram of this embodiment, three friction wheels242are shown, but there can be one or more friction wheels242, depending on the driving force required by the device of this invention. In case of a number of friction wheels242, they can be further arranged at equal distance along the outer wall of rail23. As shown inFIG. 4, the friction wheels242can be driven in synchronization via six sprockets26a–26f(three of them as take-up units) and chain27. It should be pointed out that, the supporting rollers25and friction wheels242in this embodiment are interchangeable, i.e., the friction wheels contact with the upper or lower edge of rail23, while the rollers or balls run against the side of rail23.

To monitor the sun position for tracking purpose, the directed reflection light collecting device with planar reflectors in this invention can also include a sensor5to monitor the sun position and processing circuit to receive the signals from sensor5(not shown). For more information regarding the sensor5and the sun position and processing circuit, please refer to U.S. Pat. No. 6,465,766B1, entitled “Sunlight Tracking Sensor and its Use in Full-Automatic Solar Tracking and Collecting Device,” which is incorporated herein by reference. This sensor5and its processing circuit can control the azimuth angle adjusting mechanism and altitudinal angle adjusting mechanism of the planar reflectors to adjust the azimuth angle and altitudinal angle of the planar reflectors so that they follow the change of the sunlight direction. In this way, the sunlight reflected by the planar reflectors in this invention can be projected in a substantially fixed direction into the required projection area ABCD (FIG. 3).

To realize control of the altitudinal angle adjusting mechanism of planar reflectors with sensor5so that the altitudinal changing angle of the planar reflectors is half of the sun altitudinal changing angle, the specific structure adopted is as shown inFIG. 2, the sensor5mounted facing the sun detect change of sun position, which is converted to change in the planar reflector angle via a driving mechanism with a radius ratio of R1:R2=1:2. This driving mechanism can be a synchromesh gear belt driving mechanism, comprising pulley61with a radius of R1, pulley62with a radius of R2and synchromesh gear belt63, in which pulley62is in rigid connection with the connecting rod F″C″, and sensor5in rigid connection with pulley61with the radius of R1. In this way, the processing circuit can adjust the planar reflectors for the required azimuth angle and ½ altitudinal angle according to the signals from sensor5on pulley61.

The structure of sensor5can be as shown inFIGS. 6A–6B, comprised of a light shading post001, four photosensitive elements003arranged on four sides of the post001and a base004for burying the photosensitive elements003at a certain depth. For each photosensitive element, a reflection shading block002is arranged above the ⅙–½ of receiving window close to the light shading post side wall, and the photosensitive elements003are photosensitive diodes. The photosensitive diodes003are buried in the base004at a certain depth to enhance the ability of the sensor to avoid interference by stray light; also, with the reflection shading block002arranged to shade ⅙–½ of the receiving window of the diodes, the part of the window most sensitive to receiving is exposed, making the sensor more sensitive, in particular to angular deflections at small angles.

When the sun azimuth angle changes, sensor5transmits an azimuth angle position signal to the processing circuit to drive the motor and its reducer241, which further moves the rail23and the whole parallel connecting rod mechanism on the supports21to rotate around the axial line ZZ′ so that the azimuth angle of all planar reflectors1on the parallel connecting rod mechanism is adjusted to the required position.

When the sun altitudinal angle changes, sensor5also transmits an altitudinal angle position signal to the processing circuit to drive the motor and its reducer32, which rotates transversal main turning shaft31. The power is transmitted via conical gear pair14and14′ to screw12so that nut13moves linearly along screw12. As the nut is hinged with pin15at point O′, the angle between the adjacent connecting rods A′F′E′ and F′C′ of the parallel connecting rod mechanism will change so that connecting rods A′B′ and E′D′ and connecting rod F′C′ rotates by the same angle to realize the adjustment of altitudinal angle of planar reflectors. In the meantime, according to the movement principle of the parallel connecting rod mechanism, the spacing between the book planar reflectors1is also adjusted with the change of altitudinal angle. The adjustment of the altitudinal angle of the above described planar reflectors1and the spacing between them is performed jointly with a set of a motor and its reducer32so the configuration is simple, smart and clear.

Of course, the planar reflectors described in this invention can also be attached to other parts, i.e., the frame4can also be two sets of identical parallel four-connecting-rod mechanism A′B′C′D′E′F′ and A″B″C″D″E″F″, located respectively on both sides of the planar reflectors1, and pivoted by parallel pivoting rods44in the middle. The planar reflectors1are thus fixed respectively on the parallel pivoting rods44, instead of being attached to the parallel connecting rods43in the height direction in synchronization movement so that they follow the movement of this parallel connecting rod mechanism to adjust the altitudinal angle of the planar reflectors1and their mutual spacing.

To facilitate description, only the case with three planar reflectors1is described as an example. Thus, each parallel connecting rod mechanism in this example is in the “” shape. The transversal main turning shaft31is pivoted on the centers O and O″ of the intermediate connecting rods F′C′ and F′C′, then rotatably supported on the topside of supports21of the azimuth angle adjusting mechanism, with one end in rigid connection at the output shaft of any motor driving mechanism32. In fact, the number of planar reflectors1mounted on this parallel connecting rod mechanism can be determined according to the area of the projecting zone. As required, more planar reflectors can be mounted along both sides so that the “” shaped parallel connecting rod mechanism can be further extended.

When the height of all three planar reflectors is less than the distance of the adjacent hinging points of connecting rods, although directed projection of sunlight reflected from the planar reflectors1can be ensured by the above described adjusting mechanism, there will be some unlighted space between the projections. To eliminate such spacing, further, the planar reflectors1in this invention can be specifically in rectangular shape, with the connecting lines of the four apexes on the same side of every two said adjacent planar reflectors1forming a rhombus, in which one of the diagonal lines always remains parallel with the central axial line ZZ′ of the circular rail. In this way, the projection of sunlight reflected by each adjacent planar reflector joins together and remains so all the time. This ensures that the projection of all planar reflectors in the given area is free of overlapping or unlighted space and can avoid possible unlighted space between the projections of planar reflectors or the blocking of reflectors as in the case of some existing technologies to accomplish full utilization of sunlight for sufficient lighting and even heating.

The central axial line ZZ′ is set perpendicular to the horizontal plane, i.e., the light ray reflected from the planar reflectors is perpendicular to the horizontal plane while one of the diagonal lines in the rhombus being always parallel with the horizontal plane, and the reflected sunlight can be projected vertically into the given area. Further analysis is given in the following with vertical projection as an example in conjunction with the attached figure.FIG. 11shows schematically the change of projection of light reflected by planar reflectors1when the four parallel connecting rods bring the planar reflectors1to move in this invention. To simplify, the apex of each of the planar reflectors1is approximately taken as the hinging point of the parallel connecting rod mechanism. It can be seen in the figure that, with the change of the sun altitudinal angle θ, as driven by the reciprocating linear moving mechanism, the nut at point O′ moves linearly towards point O, and the angle α of planar reflectors changes correspondingly, and at the same time, the angle β between every two adjacent connecting rods of the parallel connecting rod mechanism also changes, i.e., the parallel connecting rod mechanism becomes more narrow to adjust the mutual spacing. When the nut is at the starting point O′, or position {circle around (1)}, the projections of the light reflected from the three reflectors are respectively ad, di and il; when it reaches position {circle around (2)}, the projections from the three reflectors become respectively, eh and hk; when it reaches position {circle around (3)}, the projections from the three reflectors again become respectively cf, fg and gj. But no matter how the altitudinal angle and spacing of the planar reflectors1change, as driven by the parallel connecting rod mechanism, the projections from the three planar reflectors1remain together in the projected area, without unlighted space or overlapping.

In general, in the directed reflection light collecting device with planar reflectors, the altitudinal angle and mutual spacing of multiple planar reflectors1can be adjusted in synchronization by means of a parallel connecting rod mechanism driven by a motor-reducer set, with the technical solution that the altitudinal angle adjusting mechanism3is supported on the azimuth angle adjusting mechanism2. When the planar reflector azimuth angle is adjusted into position, the altitudinal changing angle should be adjusted to half of the changing amount of the altitudinal angle of the sun so that the sunlight can be projected in the direction of the central axial line ZZ′ of the circular rail. Furthermore, as shown inFIG. 1, the planar reflectors1in this device need not be mounted with a cantilever on one side of the transversal main turning shaft31of the altitudinal angle adjusting mechanism3to make the driving easier. The whole device features good symmetry, unique configuration, compact structure and low cost, which will facilitate its spreading and application.

Referring now toFIG. 7, another embodiment of invention is shown. The main differences in this embodiment and previous embodiment are as follows. First, the parallel connecting rod mechanism is in the “” shape as A′B′D′F′H′G′E′C′, in which the hinging point D′ of the two connecting rods C′D′ and B′D′ F′H′ in the “Y” connection is hinged onto the transversal main turning shaft31, the connection points of the other four connecting rods A′C′E′G′, A′B′, E′F′ and G′H′ are all hinged, and the transversal main turning shaft31is connected with the motor driving mechanism32. The four planar reflectors1are at the same height, equal to the distance of adjacent hinging points of connecting rods so that the connecting lines of four apexes on the same side of every two adjacent planar reflectors1form a rhombus, and the reflectors are respectively mounted on connecting rods A′B′, C′D′, E′F′ and G′H′ and opposite members. Second, the planar reflectors1are comprised of flat plates and high-efficiency light reflecting films applied onto their surfaces. Third, the screw-nut reciprocating linear moving mechanism driving the parallel connecting rod mechanism is mounted at hinging points E′ and D′, its moving part, nut13, on one end is in rigid connection by a pin at another hinging point E′, and the other end of the screw12is connected via conical gear pair14and14′ with a transversal main turning shaft31. The straight line for reciprocating movement of nut13is parallel with diagonal line G′F′ (or C′B′) and intersects the axial line of the transversal main turning shaft31. The movement of the nut13brings the up and down movement of the pin at hinging point E′, thus realizing the adjustment of planar reflectors altitudinal angle and spacing in the same way. Fourth, there is a different sensor structure. As shown inFIGS. 8A–8C, this sensor5(not shown inFIG. 7) is comprised of a cylindrical barrel004, a large lens001, four small lenses006and four photo sensitive elements007corresponding to the four small lenses006, with the large lens001at the forefront of cylindrical barrel004, the four small lenses006at the middle of the cylindrical barrel004, and the four photosensitive elements007at the rear of the cylindrical barrel004, and the output ends of photosensitive elements are connected to the processing circuit respectively. When the optical signals from all four photosensitive elements007are equal, it indicates that the sensor5is directed properly to the sun. When there is a deflection of a light ray, the output signals from two corresponding photosensitive elements will not be equal, and the processing circuit will control the operation of the motor on this basis.

Similarly, the parallel connecting rod mechanism can be a “” shaped overlapped connecting rod mechanism by adding more planar reflectors on both sides of it.

In operation, the embodiment shown inFIG. 7will produce the same effect as the environment shown inFIG. 1and therefore will not be described in detail here.

Referring now toFIGS. 9 and 10another embodiment of invention is shown. As compared with the previous embodiment, the main features are that the parallel connecting rod mechanism does not adjust the altitudinal angle and spacing of planar reflectors1by the screw-nut reciprocating linear moving mechanism. Instead, the power for the parallel connecting rod mechanism is directly from the transversal main turning shaft31connected with altitudinal angle motor driving mechanism32. The central point O of the connecting rod F′C′ in the parallel connecting rod mechanism is in rigid connection with the transversal main turning shaft31. A straight line crossing at the axial line of the transversal main turning shaft31and parallel with the diagonal line F′B′ (or E′C′) of the connecting rod mechanism intersects the adjacent connecting rod A′F′E′ at point O′, where a sliding block or pulley is provided and can slide along a straight sliding trough11mounted between the rigid connection point O and the intersecting point O′. The transversal main turning shaft31is in rigid connection with the motor driving mechanism32at one end.

In this way, when the transversal main turning shaft31is driven directly by the motor driving mechanism32, the connecting rod F′C′ in rigid connection with the transversal main turning shaft31will turn to force the point O′ on the connecting rod A′F′E′ to slide up and down in the trough11via the sliding block or pulley, thereby changing the angle between the connecting rod A′F′E′ and the connecting rod F′C′ to adjust the altitudinal angle and spacing of the planar reflectors1.

FIG. 12illustrates yet another embodiment of invention. The main differences between this embodiment from the above embodiments are, first of all, the frame4in this embodiment is an integral rigid structure. The planar reflectors1are fixed in parallel on this frame4at a fixed spacing, the transversal main turning shaft31is in rigid connection with the frame4, and the altitudinal angle adjusting mechanism3drives the transversal main turning shaft31to turn in a controlled manner to turn the integral rigid frame4, thereby enabling the planar reflectors1to adjust their altitudinal angles in synchronization. Second, a mounting relations of the parts of the azimuth angle adjusting mechanism have been adjusted in another way, as shown inFIGS. 13,14and15. As can be seen, the motor driving mechanism24is fixed on the extended lower part of the supports21, instead of on the base22. Accordingly, the rail23and the base22form a fixed integration. The friction wheels242contact the rail23, and the motor driving mechanism24drives the supports21and its extending frame to rotate around the axial line ZZ′ along the rail23. One of the three friction wheels242or of the three supporting rollers25can be in a spring loaded structure for clearance adjustment to accommodate the irregularity of rail23, as shown inFIGS. 14 and 15. This embodiment also has the effect as described for the above embodiments, except that it has no function for spacing adjustment, and therefore it is not described in detail here.

The functional difference of this embodiment from the above mentioned embodiments is that, the sunlight is not projected in the direction of the central axial line ZZ′ of the circular rail. Rather, it is projected in a fixed direction other than the central axial line ZZ′ of the circular rail.

To realize the function of this embodiment to project the sunlight in a fixed direction other than the central axial line ZZ′ of the circular rail, in addition to satisfying the condition that the planar reflector altitudinal changing angle should be half of the sun altitudinal changing angle, appropriate changes should also be made to the planar reflector azimuth angle adjusting mechanism so that the azimuth changing angle of the frame rotating around the circular rail central axial line ZZ′ of the azimuth angle adjusting mechanism, the planar reflectors on it and the supports for the frame should be half of the sun azimuth changing angle.

Referring toFIG. 17, the purpose is to have sunlight coming from point L1finally projected to the point L2below the true south via the planar reflectors at point O. In ΔOL1L2, OL6is a normal line. A corresponding point L3may be taken with respect to point L2on the same altitudinal line, and OL4is the normal line in ΔOL1L3and OL5is the normal line in ΔOL2L3. At the beginning, the normal line of planar reflectors is directed to the sun L1, and the planar reflectors are turned by ½ of the altitudinal angle α. With this, the sunlight is reflected to position OL3. On this basis, the planar reflectors continue to turn by ½ azimuth angle β so that the sunlight is reflected to position OL2. In other words, with two actions respectively in altitudinal angle and azimuth angle, the sunlight can be reflected to the fixed position of L2.

The specific structure to realize this is as shown inFIG. 16. At the end of the output shaft of the reducer241with rigid connection of friction wheel242, another reducer241′ is connected. To make a distinction, this reducer241′ is referred to as ½ azimuth angle reducer. It can be a set of gears for reduction purpose, and its output shaft is in rigid connection with another sensor5′. The belt driving mechanism comprises pulleys61and62, and synchromesh gear belt63is actually also a reducer, which can be referred to as a ½ altitudinal angle reducer. It should be noted that, the portion for sensing the azimuth angle in the original sensor5has been separated out to form sensor5′, and sensor5only detects and senses altitudinal angle. With reasonable configuration of the reduction ratio of ½ azimuth angle reducer241′, the radius of rail23and friction wheels242, finally the turning direction of rail23will agree with that of sensor5′, with the angular speed at half that of sensor5′.

This arrangement provides another solution for the lighting in rooms on ground floors for two multi-level buildings located close together. It is only necessary to install the device on the roof of one building and select a proper initial position to project the reflected sunlight directly at an inclining angle into the window of the users on the ground floor of the other building. To ensure the accuracy of directed projection of sunlight and overcome errors, locating sensor comprising four sets of photosensitive elements can be arranged around this given projection area on the windows so that sunlight will not go beyond this given area.

When the given sunlight projecting direction is perpendicular to horizontal plane, there is no obstacle to the incident light of any of the planar reflectors and no overlapping or unlighted space between the projections of reflected light rays. It can be found that, when the given projection direction of sunlight is not perpendicular to the horizontal plane, or the central axial line ZZ′ of the circular rail is inclined at a given angle with the horizontal plane, part of the incident light from the planar reflectors in the rear is perhaps shaded by the planar reflectors in front, as shown inFIG. 18. Because the circular rail is inclined, part of the two reflectors in the rear, a1a2and a3a4is shaded by the front reflector so the part of the rear reflector is not fully utilized. Further, more area will be shaded with the increase of the inclining angle. To solve this problem, reflectors are used in a ladder arrangement as shown in this embodiment.

As shown inFIG. 19, the altitudinal angle adjusting mechanism will function so that the change in planar reflector altitudinal angle is half of the change in sun altitudinal angle, and the azimuth angle adjusting mechanism will function so that the change in planar reflector azimuth angle is half of the change in sun azimuth angle.

One side of the frame is the parallel connecting rod mechanism A′B′C′D′O2O1E′F′G′H′I′, in which one connecting rod O1O2C′ is in rigid connection with the supports6. The altitudinal angle adjusting mechanism includes at least the transversal main turning shaft31that is parallel with the planar reflectors. The transversal main turning shaft31is hinge supported on connecting rod O1O2C′ and in rigid connection with connecting rod D′O2E′. The four planar reflectors are respectively fixed in parallel on all synchronously moving parallel connecting rods A′B′, D′O2, O1F′ and I′H′, in a ladder arrangement, and the parallel connecting rod mechanism is rotatably supported on the supports6via the transversal main turning shaft31. The altitudinal angle adjusting mechanism also includes the screw and nut mechanism, in which the nut13is hinge supported on connecting rod D′O2E′, the screw12is hinge supported on supports6at one end via the looper34, the motor output shaft is directly connected with screw12, and the motor is in rigid connection with the looper34. While a screw12is moving in the nut13, connecting rod D′O2E′ rotates around O2, and the angle between the adjacent connecting rods in parallel connecting rod mechanism changes to adjust the altitudinal angle of planar reflectors on the connecting rods.

The moment when the light collecting device is in the true south of the projecting direction, the sun is also in the true south, and the azimuth angle deviation at this moment is defined as zero. When viewed from one side, part of the light collecting device is as shown inFIG. 20, D′O2E′F′O1is the parallel connecting rod mechanism. The planar reflectors are fixed respectively on connecting rods D′O2and O1F′, connecting rod O1O2is in rigid connection with supports6so that the position remains unchanged so that the reflected light from both reflectors is projected in the direction pointed by O1O2without shading each other, and in no circumstance will the incident light from the rear reflector be shaded. When the sun changes position, as the parallel connecting rod mechanism is driven by the screw and nut mechanism, planar reflectors will rotate correspondingly with the transversal main turning shaft31of parallel connecting rod mechanism at point O2to adjust their altitudinal angle and mutual spacing. In addition, their azimuth angle will be adjusted with the movement of the circular rail so that both the altitudinal angle and azimuth angle of planar reflectors will change just half of the altitudinal angle and azimuth angle of the sun, and the reflected light from both planar reflectors can project in the given direction.

To overcome the problem that the front reflector might shade the rear one slightly at a specific moment due to the rigid connection of connecting rod O1O2, further optimization can be made on the basis of this embodiment, such as by changing the angle of connecting rod O1O2alone using another connecting rod mechanism or a screw-nut mechanism to eventually realize projection of reflected light rays free of overlapping or unlighted space.

Similarly to ensure the projection accuracy of sunlight in the given direction with minimized error, a positioning sensor comprising four photosensitive elements can be fit at certain position in the given direction of sunlight projection so that the sunlight will be kept in the given direction at all times.

Of course, the azimuth angle adjusting mechanism in this embodiment is not necessarily located on the side of the circular rail. The support can also be rotated by a circular rack and gear mechanism with central axial line ZZ′.

There are still some other embodiments of this invention in addition to the above embodiments. For instance: (1) the driving mechanism of the parallel connecting rod mechanism is a gear-rack reciprocating linear moving mechanism instead of a screw-nut mechanism; (2) the screw-nut driving mechanism as a reciprocating linear moving mechanism in which the nut rotates with the screw moving forward and backward instead of the screw rotating with the nut moving forward and backward; (3) the parallel connecting rod mechanisms on both sides remaining unchanged, but only one set of reciprocating linear moving mechanisms is adopted to drive the parallel connecting rod mechanism on one side, with the opposite side operating in a passive manner; (4) the screw-nut driving mechanism as reciprocating linear moving mechanism being that with motor directly driving the screw, instead of connection with transversal main turning shaft via the conical gear pair; (5) other variants of parallel connecting rod mechanisms can be used; (6) the vertical positions of parallel connecting rod mechanisms, rails and bases in the embodiment being arranged in an inverted order, i.e., the parallel connecting rod mechanism being suspended on the rail or base via the supports. Any equivalent substitution or similar combination conversion on the basis of this invention by technical personnel in this field shall be within the protection range of this invention.