| 摘要 |
PURPOSE:To always keep the area near the base in the blowing side of a lamp at the lowest temperature even when a blowing heater is set in the stand-by mode by providing the function to always keep the temperature of the lowest temperature spot set in a part of the wall surface of fluorescent lamp to a temperature lower than that of wall surface except for said lowest temperature spot. CONSTITUTION:When a lamp comes on, the temperature of wind sent into the lamp house is controlled by a blowing fan 3 by detecting a change of resistance value of a temperature detecting element 9 with a temperature controller 11 and by supplying an electric power adequately to a heater 6 in order to make constant the temperature of the lowest temperature spot 13 near the temperature detecting element 9. In the stand by condition where the lamp is turned off and power is supplied only to the filament, power is supplied to a bias heater 7 for heating, in addition to the temperature detecting element 9, temperature controller 11, heater 6 and blowing fan 3. The outside air obtained by the blowing fan 3 is heated adequately by the heater 6 and is divided into two parts by a partitioning plate 4. Accordingly, the lowest temperature spot 13 at the base in the blowing side of lamp is always lowered in its temperature in comparison with the other wall part and the mercury captured at this spot is not dispersed again. |
