| 摘要 |
PURPOSE:To prevent a heat collecting pipe from being thermally deformed when the pipe is empty by a method wherein a cover for a brilliant surface, a float movable vertically in proportion to the variation of the level of water in a tank and a blind plate operative inversely to the vertical movements of the float and facing opposite a sunlight reflecting surface are provided. CONSTITUTION:The float 4 movable vertically in proportion to the variation of the level of water in the tank 1 is provided within the tank and the blind plate 10 is provided opposite to the sunlight reflecting surface 9 of the cover 2. When no water is stored in the tank 1, the float 4 sinks so that the blind plate 10 is moved upward by a drawing string 5 and intercepts the sunlight from the sunlight reflecting surface 9 of the cover 2. On the other hand, when the water is stored in the tank, the blind plate 10 is rolled up around a roll 11 by the upward movement of the float 4 and the loosening of the drawing string 5 and the sunlight reflecting surface 9 is exposed directly to the sunlight to be heated by both the reflecting light and the direct rays of the sun. |
