| 摘要 |
PROBLEM TO BE SOLVED: To provide a sign instrument in which when the sign instrument has fallen down or has been largely displaced, such troubles can be instantly found out at a control equipment provided remote from the sign instrument, even if a person does not patrol the installation site of the sign instrument. SOLUTION: A circuit device is incorporated into a top of a cone body being a hollow cone. The circuit device includes a sensor 21 which responds at least to vibration or inclination, a condition identification circuit 22 which processes outputs of the sensor 21 to identify the occurrence of abnormal conditions due to vibration or inclination exceeding a reference value, a radio transmitter circuit 23 and an antenna 24 which inform the occurrence of abnormal conditions by means of radio signals in response to the outputs of the circuit 22, and a power source circuit 25 which supplies power to these devices. |
