Patent attributes
A cover device (2) for a drink container having an improved leak resistance comprises a basic assembly (9) which is provided with a drink opening (32) and a ring-shaped member (37), and a valve arrangement (20) for blocking or unblocking a passage to the drink opening (32) from a drink container side of the cover device (2). The valve arrangement (20) comprises a valve element (26) having a sleeve (60) with a slit (42), a circumference of the sleeve (60) being substantially similar to a circumference of the ring-shaped member (37). The leak resistance of the valve arrangement is further improved in that the sleeve (60) and the ring-shaped member (37) have a first diameter in the direction of the slit (42) and a second diameter perpendicular to the slit (42), wherein a ratio between the first and second diameters of the sleeve (60) is smaller than a ratio between the first and second diameters of the ring-shaped member (37).