To provide a door device which has a crime-preventive function imparted thereto, without power supply to a door.
According to the door device, a cover 22 is detachably arranged on a mechanical lock outer portion 15c so as to cover an insertion port for a mechanical key for a mechanical lock. Therefore the door lock cannot be locked/unlocked by the mechanical key without removing the cover 22 from the mechanical lock outer portion 15c. Then a stile 13 of the door has a first switch 26 arranged therein at a location opposed to a permanent magnet 23, for detecting presence/absence of the cover 22 on a non-contact basis. The first switch 26 is formed of a reed switch which is turned on/off based on detection of a magnetic field generated by the permanent magnet 23 embedded in the cover 22. When the first switch 26 detects that the cover 22 is removed, the door device 11 activates a buzzer arranged in the stile 13. In this manner the door device 11 has the crime preventive function imparted thereto, without power supply to the door 12.
SAKAO HIDEKI
Makoto Onda
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