短語詞組短語change e valve 換曏閥hand change over valve 手動換曏閥pneumatic change direction valve 氣動換曏閥change direction valve 換曏閥electromagnetism change direction valve 電磁換曏閥the change over valve 調(diào)壓閥change -valve 轉換閥piston buffer change valve 活塞式緩變閥 返回 change valve