non-return的用法和樣例：
詞匯搭配
- ball non-return valve 單向球閥
- non return 不返回的
- non return valve 止逆閥,單向閥...
- non return finger 單向指檔
- non-return foot valve 止回底閥
- non-return valve 單向活門(mén),單向閥...
- non-return flap valve 止回閥
- double non-return valve 雙止回閥
- non-return flap 止回瓣
- non-return trap 止回汽水閥
- non-return device 單向裝置
