短语词组短語oxycen on -off valve 氧氣開關ON -OFF air valve 氣動開關閥pneumatic on -off valve 氣動開關閥;氣動切斷閥on -off ctrol valve 兩位式控制閥的控制high -speed on-off valve 高速開關閥High Speed On -off Valve 高速開關閥 返回 on-off valve