| 摘要 |
<p>The present invention relates to a passage blocking system which allows or blocks the passage of vehicles and pedestrians and, more specifically, to an automatic blocking bar opening apparatus which automatically opens a blocking bar to enable vehicles of a specific frequency to pass without disturbance. The present invention fixates and installs a microphone connected with a microprocessor in order to be exposed to the main body of a blocking device and enables an emergency vehicle to pass through urgently by blocking a first blocking bar while opening a second blocking bar by operating a driving unit by a control program of the microprocessor if a sound having a frequency and a decibel (db), which belong to an emergency vehicle, is sensed in a frequency/decibel reading unit after receiving the frequency and the decibel by a siren sound generated in the emergency vehicle through the microphone and amplifying the frequency and the decibel in an amplifying unit.</p> |
