Patent ID: 7537133

Claim:
A valve device for a drinking container having an internal volume for containing fluid, the valve device comprising: a wall portion separating the internal volume of the drinking container from a suction chamber, the wall portion defining a wall opening that connects the internal volume to the suction chamber, the suction chamber also being connected to a downstream drinking opening for said fluid; and a valve that is movable between an open position wherein fluid in the internal volume can flow out of the drinking container via said wall opening and further via said suction chamber and drinking opening, and a closed position wherein fluid in the internal volume cannot flow out of the drinking container via said wall opening, suction chamber and drinking opening; wherein the valve comprises a pressure-responsive movable membrane, at least one bracing element and a sealing element, the bracing element connecting the membrane to the sealing element such that movement of the membrane causes movement of the sealing element; wherein in the closed position the sealing element seals against fluid outflow via the wall opening, and in the open position the sealing element does not seal against fluid outflow via the wall opening; wherein the movable membrane has at least one surface exposed to pressure in the suction chamber, and at least one opposite surface exposed to ambient pressure outside the drinking container; wherein the sealing element has at least one surface exposed to the pressure in the internal volume of the drinking container, the internal pressure being equal to or higher than ambient pressure; wherein application of a predetermined amount of suction at the drinking opening reduces the pressure in the suction chamber below ambient pressure so as to produce a differential pressure across the membrane, whereby said differential pressure acts on the membrane to move the membrane in the direction of the suction chamber and thereby force the sealing element and thus the valve out of the closed position; wherein said bracing element comprises at least one stem; and wherein the stem is positioned within, and projects axially out from, an outflow opening provided in the membrane, and wherein the stem is secured in a manner allowing for unobstructed fluid flow through the outflow opening when the valve is in the open position.