CLOSURE DEVICE FOR A FLUID CONTAINER

A closure device for a fluid container, in particular a hydraulic tank, having a base (), which can be attached to the container opening thereof, and a cover part (), which encloses a ventilation and/or a filter device (), is held on the base () so as to be freely rotatable in a functional unlocking position and, in a further functional locking position, permits the container opening to be unlocked by means of a safety device () while connecting the cover part () to the base (), is characterized in that the safety device () can be actuated by a device generating a magnetic field (), which device establishes the further locked functional position of the cover () and the base () by means of magnetic force.