Cover device for a drink container

A cover device (2) for a drink container comprises a basic assembly (9) which is provided with a drink opening (32), 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 two portions (27, 28) which are connected to each other through an area of the valve element (26) at a position where the valve element (26) is hingably associated with the basic assembly (9), and wherein only one of the two portions (27, 28) is in direct communication with the drink opening (32) of the basic assembly (9), so that a smallest total moment of force may be realized on the one portion (28) when the valve element (26) is subjected to pressure from the drink container side of the cover device (2).