| 摘要 |
This vent plug consists of a hollow cylindrical body (1) closed at its top and open at its lower part, equipped with a plurality of fins in the shape of discs (4, 5, 6), extending from the lateral surface and the peripheral edge of which bears, with a sealing effect, against the internal lateral surface of the filling hole. These fins are fitted with openings offset with respect to one another in the circumferential sense. The cylindrical body has escape holes (8) on its sidewall which open out between one fin and the following one in positions which are at least partly offset with respect to the openings of the fins, and an upper escape hole is provided in an annular flange for extending the upper surface of the base of the cylindrical body, the upper escape hole being itself offset with respect to the openings in the fins. <IMAGE> |
