A/A = Pneumatic Air to Air.A/SR = Pneumatic Air to Spring Return (fail-safe).E = Electric (motor driven).是什么意思_A/A = Pneumatic Air to Air.A/SR = Pneumatic Air to Spring Return (fail-safe).E = Electric (motor driven).在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句