| 摘要 |
PROBLEM TO BE SOLVED: To increase the service life of a light emitting element and save electric energy to be spent thereby. SOLUTION: This safety device is provided with biparting doors 3, 4 disposed at the entrance of a car 1 so as to open and close freely, light emitting elements Lk-1 , Lk , Lk+1 of (n) pieces fitted on either of the doors 3, 4, light receiving elements Pk-1 , Pk , Pk+1 which are fitted on the other door and faces the light emitting element, and a control panel which turns on the light emitting elements of (n) pieces at intervals of (t) hours sequentially, and recognizes that the door is in a fully closed condition when the light emitted from the light emitting element is received by only the light emitting element facing on the front side, where the illuminating interval of the light emitting element is taken as (n×t) when the control panel recognizes that the door is in the fully closed condition.
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