Solar controlled sun tracker for a sunbather

Apparatus for rotating an object about an axis such that the orientation of said object relative to said axis has a predetermined relationship to the location of the sun relative to said object, said apparatus comprising:

• a base defining an axis;
• rotation means associated with said base for supporting said object and for selectively rotating said object in a first direction about said axis in response to a first control signal and in a second direction about said axis in response to a second control signal;
• control signal generating means for selectively generating said first and second control signals so as to cause said rotation means to rotate said object about said axis until the orientation of said object relative to said axis has a predetermined relationship to the location of the sun relative to said object;
• said control signal generating means comprising:
• first and second photodetectors each having a solar radiation receiving surface and an output signal which varies as a function of the intensity of solar radiation falling on said solar radiation receiving surface;
• first and second planar elements disposed at an angle of between 0 and 180 degrees to each other such that the apex of said angle defines a line, said line being coplanar with said axis, and said first and second planar elements being coupled to said object so that said first and second planar elements rotate about said line in a predetermined relationship to the rotation of said object about said axis, and said first and said second photodetectors are attached to said first and said second planar elements respectively such that said radiation receiving surfaces of said photodetectors are disposed substantially parallel to their associated respective planar elements and face the interior of said angle;
• and
• comparator means connected between said photodetectors and said rotation means for receiving said output signals from said first and said second photodetectors and for providing said first and second control signals to said rotation means, said first control signal being adapted to cause said rotation means to rotate said object in a first direction about said axis when the output signal of said first photodetector exceeds the output signal of said second photodetector, and said second control signal being adapted to cause said rotation means to rotate said object in a second direction about said axis when said output signal of said second photodetector exceeds the output of said first photodetector.