| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the hunting phenomenon of an emergency switch in an abnormal mode of a green lamp for a traffic signal lamp controller which cuts the supply of power to all green lamps via the emergency switch when a traffic light has the lighting control abnormality of the green lamp. SOLUTION: The lines M1 to Mn are set in parallel to the exciting contacts r1 to rn , and the voltage sensors D1 to Dn detect the OFF states of the semiconductor switches A1 to Sn which control the lighting of G lamps L1 to Ln . A monitor device 3 inputs the output signals of all sensors D1 to Dn to an AND circuits A1 and monitors the abnormality of lamps L1 to Ln by using the output of the circuit A1 as its trigger input. A self-holding circuit 2 uses the output of the device 3 as a hold signal. Then an electromagnetic relay RL is driven by the output of the circuit 2 and via drive circuit 4.</p> |
