Tank with ventilation canal comprising cover

1. A tank for storing a liquid, comprising a wall made of plastic and a fill-stop device for stopping the filling of said tank with a liquid at a maximum fill level, said tank comprising a port to communicate with the outside of the tank, said fill-stop device extending inside the tank and comprising at least one opening located inside the tank and a ventilation canal extending between the port and the opening, wherein a position of the opening inside said tank fixes said maximum fill level wherein said fill-stop device stops tank filling when the liquid reaches the opening which is positioned inside the tank, said fill-stop device comprising a first part formed with said wall and a second part which is fixed hermetically to said first part and wherein said first part comprises reliefs moulded on an internal face of said wall, and wherein said second pan comprises a cover which is fixed hermetically to said reliefs.

2. The tank according to claim 1 , wherein said opening is formed by said cover and by said reliefs.

3. The tank according to claim 1 , wherein said cover comprises a through-orifice forming said opening.

4. The tank according to claim 1 , wherein a portion of said first part that bears said second part, said first part forms part of a lateral wall of said fill-stop device in each cross section perpendicular to a longitudinal direction in which said fill-stop device extends, a rest of said lateral wall being formed by said second part.

5. The tank according to claim 1 , wherein said wall has a first port via which said fill-stop device communicates with the outside of said tank.

6. The tank according to claim 1 , wherein said reliefs are formed by ribs extending transversely towards the inside of said tank, said cover being fixed to the edges of said ribs.

7. The tank according to claim 1 , wherein said reliefs are formed by a groove, said cover being fixed over said groove.

8. The tank according to claim 1 , wherein said cover is a plate.

9. The tank according to claim 1 , comprising a device for the filling said tank with a liquid, said filling device being formed in part by part of said reliefs and in part by said cover which is fixed hermetically to said reliefs, said filling device having an opening which opens to the inside of the tank and through which a liquid is able to flow.

10. A method of manufacturing a tank for storing a liquid, this method comprising the following steps:

a) supplying a first half of a tank comprising a wall made of plastic and comprising a first part of a device for stopping the filling of said tank with a liquid at a maximum fill level, said first part being formed with said wall,

b) fixing a second part hermetically to said first part, said second part forming, with said first part, said fill-stop device, said fill-stop device comprising at least one opening located inside the tank and a ventilation canal extending between the opening and a port allowing a communication without the outside of the tank, wherein the position of the opening within said tank fixes said maximum fill level wherein said fill-stop device stops tank filling when the liquid reaches the opening which is positioned inside the tank, wherein said first part comprises reliefs moulded on an internal face of said wall, and wherein said second part comprises a cover which is fixed hermetically to said reliefs,

c) fixing a second half of said tank to said first half of the tank so as to form this tank, said fill-stop device extending inside said tank.

11. The method according to claim 10 , wherein said fill-stop device is a ventilation duct.

12. The method according to claim 10 , wherein said fill-stop device allows a fill stop when the liquid reaches the opening inside the tank.

13. The method according to claim 10 , wherein said first part and said second part form a hermetic duct opened at its two endpoints, wherein a first endpoint is in contact with the wall in front of an opening made into said wall and a second endpoint forms the opening inside the tank.

14. The method according to claim 1 , wherein said fill-stop device is a ventilation duct.

15. The tank according to claim 1 , wherein said first part and said second part form a hermetic duct opened at its two endpoints, wherein a first endpoint is in contact with the wall in front of an opening made into said wall and a second endpoint forms the opening inside the tank.

16. The method according to claim 10 , wherein said opening is formed by said cover and by said reliefs.