Abstract: An opening and closing device of a gasoline tank cap is disposed between an upper cap and a base of the tank cap, and includes a valve, a valve cap controlling the valve to rotate to let its valve hole communicate or not with an upper opening of the upper cap. Thus, the tank cap is not needed to be taken off completely for pouring gasoline in the tank. So filling gasoline in the tank is quite convenient, saving time, and preventing the tank cap from being lost by frequent removing for pouring gasoline in.

Abstract: A cover assembly for a container includes: a cylinder base body with an axial bore therethrough, a lower portion for engaging an entry of the container, and an annular flange extending inwardly and radially into the axial bore; a shield mounted on an upper portion of the base body and having a central opening aligned with the axial bore of the base body; and a valve unit including a coil spring provided within the axial bore and placed on the annular flange, a hollow cylinder-shaped valve seat provided axially in the axial bore of the base body and inserted into the coil spring such that the valve seat can communicated with the container. The valve seat has an outwardly and radially extending press member which is biased by the coil spring toward the shield, and a blocking valve with a spherical external face and an axial hole extending therethrough.