| 摘要 |
PROBLEM TO BE SOLVED: To suppress the possibility of the traveling by a driver in an unsatisfied state of necessary sufficient luminous flux amount when a part of a lighting fixture becomes out of lighting and to make an alarm device have a simple constitution. SOLUTION: This alarm device detects short circuit failures or open failures generated in a plurality of electronic light emitting elements 1 and 2 connected in parallel to give an alarm. The alarm device is provided with a plurality first resistors 3 and 4 connected to each of anodes of the plurality of electronic light emitting elements 1 and 2, a plurality of second resistors 5 and 6 connected to each of cathodes of the plurality of electronic light emitting elements 1 and 2, a short circuit failure threshold value voltage source 7, an open failure threshold value voltage source 8, a plurality of first comparators 9 and 10 for comparing each of anode voltage of the plurality of the electronic light emitting elements 1 and 2 with short circuit threshold value voltage, a plurality of second comparators 11 and 12 for comparing each of cathode voltage of the plurality of electronic light emitting elements 1 and 2 with open threshold value voltage, and a shutoff switch 13 for shutting off supply current to the plurality of electronic light emitting elements 1 and 2 based on judgment results of the open failures or the short circuit failures from the plurality of the first comparators 9 and 10 and the plurality of the second comparators 11 and 12. COPYRIGHT: (C)2006,JPO&NCIPI
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