Closing device for a filler neck disposed on a container

A closing device for a filler neck situated on a container, said container having at least one filler neck which is provided with a through opening and is connected to the container interior, said closing device comprising:

• a first closure element for closing or opening the through opening of the filler neck from the outside;
• a second closure element for closing or opening the through opening of the filler neck from the inside;
• a pivot device defining a vertical axis and operatively connected to the first and second closure elements for pivoting the first and second closure elements about the vertical axis in relation to the through opening of the filler neck;
• an activatable drive means for operating the pivot device;
• and
• seals respectively situated on each of the first and second closure elements, wherein at least one seal has a circumferential pressure chamber fluidly connected to a supply line, said pressure chamber being under pressure in a closed position of the closure elements and pressure-relieved in an open position of the closure elements.