Valve assembly for leak resistant straw cup

1. A valve assembly for a leak resistance drinking cup, the valve assembly being selectively configurable between a sealed position and an unsealed position, the valve assembly comprising a plug having a first side, a second side opposite the first side, an inner surface extending from the first side to the second side, an outer surface extending from the first side to the second side, and an opening extending through the plug from the outer surface to the inner surface, the inner surface including an angled surface portion surrounding the opening, wherein the inner surface has an effectively smaller surface area than the outer surface, and wherein a total surface area of the inner surface is greater than a total surface area of the outer surface, an amount of vacuum acting on the outer surface of the plug needed to move the valve assembly from the sealed position to the unsealed position being of lesser magnitude than the amount of internal pressure acting on the inner surface of the plug needed to move the valve assembly from the sealed position to the unsealed position.

2. The valve assembly of claim 1 wherein the outer surface of the plug is recessed.

3. The valve assembly of claim 2 wherein the outer surface of the plug is circular.

4. The valve assembly of claim 1 wherein the inner surface of the plug is adapted to form a seal with a component of the leak resistant drinking cup in the sealed position.

5. The valve assembly of claim 1 wherein an amount of vacuum acting on the outer surface needed to move the valve assembly between the sealed and unsealed positions is less than 5 inches of mercury and an amount of positive pressure acting on the inner surface needed to move the valve assembly between the sealed and unsealed positions is greater than 6 inches of mercury.

6. The valve assembly of claim 5 wherein the amount of vacuum acting on the outer surface needed to move the valve assembly between the sealed and unsealed positions is less than 3 inches of mercury.

7. The valve assembly of claim 6 wherein the amount of positive pressure acting on the inner surface needed to move the valve assembly between the sealed and unsealed positions is greater than 8 inches of mercury.

8. The valve assembly of claim 7 wherein the amount of positive pressure acting on the inner surface needed to move the valve assembly between the sealed and unsealed positions is greater than 15 inches of mercury.

9. A valve assembly for a leak resistance drinking cup, the valve assembly being selectively configurable between a sealed position and an unsealed position, the valve assembly comprising a plug having an inner surface, an outer surface, and an opening extending through the plug from the outer surface to the inner surface, wherein the inner surface has an effectively smaller surface area than the outer surface, and wherein a total surface area of the inner surface is greater than a total surface area of the outer surface, an amount of vacuum needed to move the valve assembly between the sealed and unsealed positions being less than 5 inches of mercury, an amount of positive pressure needed to move the valve assembly between the sealed and unsealed positions being greater than 6 inches of mercury.

10. The valve assembly of claim 9 wherein the amount of vacuum needed to move the valve assembly between the sealed and unsealed positions is less than 3 inches of mercury.

11. The valve assembly of claim 9 wherein the amount of positive pressure needed to move the valve assembly between the sealed and unsealed positions is greater than 8 inches of mercury.

12. The valve assembly of claim 11 wherein the amount of positive pressure needed to move the valve assembly between the sealed and unsealed positions is greater than 15 inches of mercury.

13. The valve assembly of claim 10 wherein the inner surface of the plug includes an angled surface portion and an annular surface portion circumscribing the opening, the annular surface portion being adapted to form a seal with a component of the leak resistant drinking cup in the sealed position.

14. A valve assembly for a leak resistant drinking cup, the valve assembly comprising a plug having an inner surface, an outer surface, and an opening extending through the plug from the outer surface to the inner surface, the inner surface of the plug including an angled surface portion and an annular surface portion circumscribing the opening, the annular surface portion being adapted to form a seal with a component of the leak resistant drinking cup, the total surface area of the inner surface being greater than the total surface area of the outer surface, the total surface area of the outer surface being greater than the surface area of the angled surface portion of the inner surface.

15. The valve assembly of claim 14 wherein an amount of vacuum acting on the outer surface of the plug needed to move the valve assembly from a sealed position to an unsealed position is less than the amount of internal pressure acting on the inner surface of the plug needed to move the valve assembly from the sealed position to the unsealed position.

16. The valve assembly of claim 15 wherein an amount of vacuum acting on the outer surface needed to move the valve assembly between the sealed and unsealed positions is less than 5 inches of mercury and an amount of positive pressure acting on the inner surface needed to move the valve assembly between the sealed and unsealed positions is greater than 6 inches of mercury.

17. The valve assembly of claim 16 wherein the amount of vacuum acting on the outer surface needed to move the valve assembly between the sealed and unsealed positions is less than 3 inches of mercury.

18. The valve assembly of claim 17 wherein the amount of positive pressure acting on the inner surface needed to move the valve assembly between the sealed and unsealed positions is greater than 8 inches of mercury.