| 摘要 |
<p>PURPOSE:To eliminate a dangerous condition of the opened valve due to a movement of the bobbin caused by a vibration etc., under a closed valve condition by a method wherein a reverse electric current is applied to the solenoid valve in case of the valve is closed to provide an additional valve closing force. CONSTITUTION:When a signal from an arithmetic operation processing device 23 is shut off and the first and the second transistors 22, 26 are turned OFF, the voltage at the point a is gradually increased, and finally the third transistor 29 is turned ON to form a closed circuit of power supply 28, solenoid 31, and the third transistor 29. To the solenoid coil 16 is applied a reversing electric current of upward direction. The bobbin 17 accepts a force having the same direction as that of the biasing forces of the springs 19 and 20 and then restricted for its seating condition. In case of the valve being closed, even if the solenoid valve 1 receives the vibration, the bobbin 17 stays still and surplus air is not required to be fed to the catalyst A.</p> |
