| 摘要 |
<p>PURPOSE:To assure safety for the passing in a corridor, the ascent/descent on a staircase, and the entrance/exit to a room by detecting a human body somewhat in the foreground while a lamp is turned off. CONSTITUTION:An automatic turning-on/off control device of an illuminating lamp is provided with human body detecting sensors 11, 24 detecting a human body entering the foot of a staircase or the head of the staircase respectively, an illuminance detecting sensor 27 detecting the illuminance of the staircase, a selecting circuit 14 setting a staircase lamp 1 to the low- illuminance on-mode and the off-mode, and a throttle shutter 19 changing the detecting range of the human body detecting sensor 11 based on the selection signal SW outputted from the selecting circuit 14. When the illuminance detected by the illuminance detecting sensor 27 is the prescribed illuminance or above, the staircase lamp 1 is set to the off-state. When the illuminance is below the prescribed illuminance, the staircase lamp 1 is set to the low- illuminance on-state or the off-state based on the output of the selecting circuit 14. When the off-mode is selected, the detecting range of the human body detecting sensor 11 is expanded to the maximum detecting range. The human body entering the foot of the staircase while the staircase lamp 1 is turned off is detected by the human body detecting sensor 11 sufficiently in the foreground, and a control circuit 23 turns on the staircase lamp 1 for the prescribed period at high illuminance.</p> |
