| 摘要 |
PURPOSE:To contrive to prevent the collecting plate from deterioration caused by the abnormal high temperature and achieve the effective heat collecting by a method wherein an abnormal heating preventive means is formed by overlapping each side edge of many belt-shaped synthetic resin transparent films, and the abnormal heating preventive means is arranged between a heat collecting part and a transparent cover. CONSTITUTION:The upper opening of a casing 1 is covered with a transparent glass plate 2. A heat collecting plate 3 and heat insulating material 5 are arranged on the bottom surface of a casing 1, the heat collecting plate 3 is formed of several heating medium tubes 4 arranged along lengthwise direction, the lower surface of the heat collecting plate 3 is lagged with the heat insulating material 5. The surface of the heat collecting plate 3 is a selective absorption surface. Many belt-shaped transparent films 6 which are made of fluororesin are paralleled in lengthwise direction between the heat collecting plate 3 and the transparent glass 2 with extending over between opposite lengthwise walls of a casing. The films 6 are arranged alternatively in high and low positions, also each side edge thereof is overlapped. In normal operation, the transparent films 6 produce the heat insulation effect by preventing the heat collecting plate 3 from heat dissipation toward upper direction. The transparent films 6 initiate the heat emission with rising to high temperature caused by the radiant heat from the heat collecting plate 3. |
