| 摘要 |
A non-return valve comprises a tubular member 2 for insertion into a pipe, the tubular member having an entrance port 3, an exit port 4 and a side wall 5. A lid 8 is pivotally connected to the tubular member 2 between open and closed positions. An engagement mechanism 14 extends from the side wall 5 near the exit port 4 and a locking arm 11 is connected by means of a pivot 13 to the lid 8. The locking arm 11 pivots with respect to the lid 8 about the pivot 13 between an unlocked position and a locked position. When the lid is closed and the locking arm 11 is in the locked position the locking arm engages the engagement mechanism 14. |
