The solenoid plunger pulls the vent valve down, blocking off the passage to the charcoal canister. 电磁柱塞拉下通气阀，堵住通向活性碳罐的通路。
A pilot-operated vent valve for pressure relief uses tank pressure, not weights or a spring, to keep the vent valve seat closed. 先导式通气阀泄压时利用储罐压力，而不是重力或弹簧外力，来保持通气阀阀座关闭。
