| 摘要 |
PURPOSE:To surely protect current limitting circuits, etc., from thermal damages without regard to changes of lighting conditions of plural display elements at the time of the stoppage of a cooling fan, etc. CONSTITUTION:In a display device provided with plural elements 2, a current limitting circuit board 7 on which current limitting circuits 6 performing lighting controls of these elements 2 are mounted, a power circuit board 5 on which a power source circuit 3 supplying electric power to display elements 2 via current limitting circuits 6 is mounted and a cabinet on whose front plane display elements 2 arc attached and in which these boards 5, 7 are incorporated and a cooling fan 9 allowing a cooling wind to flow into the inside of the cabinet, this device is provided with a dummy resistor RD connected with the power source circuit 3 and also having a higher temp. characteristic than current limitting circuits 6 and being arranged at a position where the resistor receives the influence of the cooling wind due to the cooling fan 9 and a thermal protecter 12 interrupting the electric power supply of the power source circuit 3 by responding to the temp. of the dummy resistor RD. |
