Abstract:
An improved elastic compression type solar tracking device includes a photoelectric plate or solar energy collecting device supported by an elastic element. A compression status of the elastic element can be changed by filling water into a water tank mounted on the photoelectric plate or solar energy collecting device to adjust the angle between the photoelectric plate or solar energy collecting device and a horizontal plane for maximum solar energy absorbing effect. The elastic compression type solar tracking device can be mounted on both sloping roofs and flat roofs of buildings.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a solar tracking device and, more particularly, to an elastic compression type solar tracking device. 
         [0003]    2. Description of the Related Art 
         [0004]    Currently available photoelectric plates or solar energy collecting devices are fixed and, thus, have unsatisfactory effect. Taiwan Utility Model No. M284856 discloses a spring type solar tracking device that allows the photoelectric plates or solar energy collecting devices to be in a better angle facing the sun for obtaining a better effect in absorption of solar energy. As a result, the solar tracking device can allow the photoelectric plates or solar energy collecting devices to face the sun at any time and, thus, greatly enhance the solar energy absorbing efficiency at low costs while consuming less energy. Specifically, one or more photoelectric plates or solar energy collecting devices are utilized to absorb solar energy, with springs provided in the east and the west, and with one or more water tanks provided in the east, wherein water can be filled into the water tanks to provide the photoelectric plates or solar energy collecting devices with a tendency to turn toward the east. One or more rotational shafts are provided to allow the photoelectric plates or solar energy collecting devices to turn toward the east or the west. However, the solar tracking device can only be used on a flat surface; namely, the solar tracking device cannot be used on a sloping roof of a building that is common in oriental and western architecture for presenting aesthetically pleasing outlines. As a result, application of such a solar tracking device is limited. 
       SUMMARY OF THE INVENTION 
       [0005]    In view of the above problems, the present invention is intended to provide a solar tracking device that can be used on both sloping roofs and flat roofs of buildings. An elastic compression type solar tracking device according to the preferred teachings of the present invention includes a photoelectric plate or solar energy collecting device; an elastic element abutting against and supporting an irradiated side of the photoelectric plate or solar energy collecting device at a first supporting point; a rotational shaft connected to and supporting the photoelectric plate or solar energy collecting device at a second supporting point between the first supporting point and an end edge of the photoelectric plate or solar energy collecting device; a post for supporting the rotational shaft; a water tank mounted on the photoelectric plate or solar energy collecting device in a location other than the second supporting point where the rotational shaft supports the photoelectric plate or solar energy collecting device, with the water tank including a water filling control valve and a water discharge control valve; an angle detecting device for detecting an angle between the photoelectric plate or solar energy collecting device and a horizontal line and sending a signal regarding information of the angle; and a controller for receiving and processing the signal from the angle detecting device for selectively proceeding with control of opening/closing, partially open extent, and a period of time of opening/closing or partially opening of the water filling control valve and the water discharge control valve. 
         [0006]    The compression state of the elastic element can be changed by filling water into the water tank to adjust the angle facing the sun for maximum effect. Thus, the solar tracking device according to the preferred teachings of the present invention can be utilized on both sloping roofs and flat roofs of buildings. 
         [0007]    Other objectives, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  shows a schematic view of a solar tracking device according to the preferred teachings of the present invention used on a sloping roof. 
           [0009]      FIG. 2  shows a schematic view of a solar tracking device according to the preferred teachings of the present invention used on a flat ground or a flat roof. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0010]    With reference to  FIG. 1 , an elastic compression type solar tracking device according to the preferred teachings of the present invention includes a photoelectric plate or solar energy collecting device  81  that is substantially plate-like and includes an irradiated side  811  and a shaded side  812 . An elastic element  85  has an end abutting against the irradiated side  812  of the photoelectric plate or solar energy collecting device  81  to form a supporting point P 1 . The elastic element  85  may be an element allowing longitudinal elastic compression and preferably a spring. The elastic element  85  supports a point of the photoelectric plate or solar energy collecting device  81 . Furthermore, the elastic element  85  and a post  86  together provide support for the photoelectric plate or solar energy collecting device  81 . Nevertheless, the elastic element  85  can be compressed to different extends in response to different pressures and, thus, has a varying height in the vertical direction (the height of the elastic element  85  in the compressed state is different from that of the elastic element  85  in the restored state). Thus, the upper end of the elastic element  85  can be at different levels with reference to the post  86 . Thus, the photoelectric plate or solar energy collecting device  81  can be located in a slanted state to change an angle between the irradiated side  811  of the photoelectric plate or solar energy collecting device  81  and a horizontal line L. 
         [0011]    A rotational shaft  82  is coupled to the photoelectric plate or solar energy collecting device  81  at a supporting point P 2  between the supporting point P 1  where the elastic element  85  supports the photoelectric plate or solar energy collecting device  81  and an end edge of the photoelectric plate or solar energy collecting device  81 , allowing the photoelectric plate or solar energy collecting device  81  to turn about the rotational shaft  82 . Preferably, the rotational shaft  82  is located at the end edge of the photoelectric plate or solar energy collecting device  81 . 
         [0012]    The post  86  supports the rotational shaft  82  and, hence, the end edge of the photoelectric plate or solar energy collecting device  81 . The post  86  is mounted on a ground, a flat roof of a building, or a sloping roof of a building. In the embodiment shown in  FIG. 1 , the post  86  is mounted on a top of a sloping roof  801 . In the embodiment shown in  FIG. 2 , the post  86  is mounted on a flat roof  802 . 
         [0013]    A water tank  83  is mounted on the photoelectric plate or solar energy collecting device  81  in a location other than the supporting point P 2  where the rotational shaft  82  supports the photoelectric plate or solar energy collecting device  81 . Preferably, the water tank  83  is located at the other end edge P 3  of the photoelectric plate or solar energy collecting device  81  opposite to the end edge P 2  where the rotational shaft  82  supports the photoelectric plate or solar energy collecting device  81  to provide a long arm of force. Furthermore, the water tank  83  can be mounted on the irradiated side  811  or the shaded side  812  of the photoelectric plate or solar energy collecting device  81  as long as the water tank  83  can apply a downward force to the photoelectric plate or solar energy collecting device  81 . 
         [0014]    The water tank  83  includes a water filling control valve  831  and a water discharge control valve  832 . Pipes are connected to the water filling control valve  831  and the water discharge control valve  832  for the purposes of filling or discharging water, wherein piping of which is omitted. When strong wind is coming, the water tank  83  can be filled with water to weight and, thus, retain the photoelectric plate or solar energy collecting device  81 , avoiding the photoelectric plate or solar energy collecting device  81  from windlift. 
         [0015]    An angle detecting device  84  is arranged to detect the angle between the photoelectric plate or solar energy collecting device  81  and the horizontal line L. A controller  87  is connected to the angle detecting device  84  for receiving and processing a signal regarding information of the angle from the angle detecting device  84 . After processing, the controller  87  selectively proceeds with control of opening/closing, partially open extent, and a period of time of opening/closing or partially opening of the water filling control valve  831  and the water discharge control valve  832 . 
         [0016]    Operation of the solar tracking device according to the preferred teachings of the present invention will now be described. The water tank  83  is initially empty, and the water filling control valve  831  and the water discharge control valve  832  are closed. The elastic element  85  is in its extended state such that the photoelectric plate or solar energy collecting device  81  has a maximum angle with the horizontal line L. After “sunrise”, the water filling control valve  831  is opened to allow filling of water into the water tank  83 . The controller  87  includes a timer connected to the water filling control valve  831  for controlling opening or partially open extent of the water filling control valve  831 . The term “sunrise” used herein can be defined by the time preset by the timer in the controller  87 . Alternatively, weather data including the trajectory of the sun, sunrise, and sunset of a given time and date as well as other weather data can be input into computer programs to obtain a predicated angle at any given time as the control parameters for controlling the water filling control valve  31  and/or the water discharge control valve  832 . 
         [0017]    The more the water is filled, the heavier the water tank  83  is and the more the elastic element  85  is compressed. As a result, the angle between the photoelectric plate or solar energy collecting device  81  and the horizontal line L becomes smaller. 
         [0018]    The angle detecting device  84  may have various structures. Most importantly, the angle detecting device  84  is capable of detecting a change in the angle between the photoelectric plate or solar energy collecting device  81  and the horizontal line L and of sending a signal to the controller  87 . In a case that the controller  87  detects that a certain angle is met within a preset period of time, the controller  87  closes the water filling control valve  831 . Furthermore, when a preset period of time or a preset angle corresponding to the time or angle of sunset has passed, the controller  87  closes the water filling control valve  831 . When the sun is below the horizon or a preset nighttime hour comes, the controller  87  opens the water discharge control valve  832  to empty the water tank  83  for tomorrow&#39;s use. 
         [0019]    Although specific embodiments have been illustrated and described, numerous modifications and variations are still possible without departing from the teachings of the invention. The scope of the invention is limited by the accompanying claims.