Plastic fuel tank comprising a noise reduction baffle and process for manufacturing it

A process for making a plastic fuel tank comprising a noise reduction baffle and interference sections for suppressing tank deformation in the case of application of negative pressure to said tank, the interference sections projecting inward in the tank from an upper surface and a lower surface thereof respectively, and being disposed so as to be substantially opposed with a specified interval between them, said process comprising the following steps:

• a parison is given the shape of the fuel tank using a mold with two cavities:
• one for the lower part of the tank and which includes a device which molds a dove tail in one piece with said lower part;
• and one for the upper part of the tank and which includes a device which molds the upper interference section as one piece with the tank wall;
• the molded tank is allowed to cool down and solidify;
• a fixation bar comprising a slit and a foot with a spider clip is provided;
• the baffle is inserted into the slit of the bar and a cover is fixed on said bar in order to provide the lower interference section;
• wherein the baffle/fixation bar/cover assembly is inserted through an opening into the tank, and wherein the spider clip of the fixation bar is inserted into the dove tail, such that in the case of application of a predetermined value of the negative pressure to the tank, said interference sections come into contact with each other, the interference sections not being in contact with each other otherwise.

A plastic fuel tank comprising:

• a noise reduction baffle and
• interference sections that suppress tank deformation in the case of application of negative pressure to said tank, the interference sections projecting inward in the tank from an upper surface and a lower surface thereof respectively, and being disposed so as to be substantially opposed with a specified interval between them, wherein
• one of the interference sections is part of a fixation device which secures the baffle to the tank wall and is molded as one piece with the baffle, and
• wherein the fixation device is a hollow part which comprises a vertical slit into which the baffle is inserted.