Drink cup lid
A liquid container includes a cup having a brim forming an opening into an interior region of the cup. The container also includes a lid configured to mount on the brim of the cup to close the opening.
1. A liquid container comprising
a cup including a brim, a floor, and a side wall extending from the brim toward the floor, the side wall including a frustoconical inner surface cooperating with the floor to form an interior liquid reservoir chamber of the cup, the brim including a curved outer boundary surface mating with an uppermost portion of the frustoconical inner surface of the side wall and extending away from the uppermost portion, the curved outer boundary surface of the brim having a rounded shape in vertical cross section that extends along a generally circular path and subtends an angle of at least 180° , the curved outer boundary surface of the brim having an annular inner sealing portion adjacent to the frustoconical inner surface of the side wall, an annular outer sealing portion away from the inner sealing portion, and an annular middle sealing portion interposed between the annular inner and outer sealing portions, and
a lid including a central closure and a brim mount coupled to the central closure and mounted on the curved outer boundary surface of the brim to retain the central closure in a position closing a mouth opening into the interior liquid reservoir chamber in the cup, the brim mount including a first seal ring with a first sloped inner surface which engages the uppermost portion of the frustoconical inner surface of the side wall to establish a first annular liquid flow barrier between the lid and the cup, a second seal ring with a second sloped inner surface which engages the annular inner sealing portion of the curved outer boundary surface of the brim to establish a second annular liquid flow barrier between the lid and the cup, a third seal ring with a third sloped inner surface which engages the annular middle sealing portion of the curved outer boundary surface of the brim to establish a third annular liquid flow barrier between the lid and the cup, and a fourth seal ring with a fourth sloped inner surface which engages the annular outer sealing portion of the curved outer boundary surface of the brim to establish a fourth annular liquid flow barrier between the lid and the cup;
wherein each of the first, second, third, and fourth sloped inner surfaces are defined relative to a horizontal axis up;
wherein the first sloped inner surface that mates with the companion surface of the cup has a greater slope than the second sloped inner surface that mates with the companion surface of the cup;
wherein the second sloped inner surface has a greater slope than the fourth sloped inner surface;
wherein each of the first, second, and third seal rings has a frustoconical shape and the fourth seal ring has a curved shape.
2. The liquid container of claim 1 , wherein the sloped inner surface of each of the first, second, and fourth seal rings has a generally positive slope and the sloped inner surface of the third seal ring has a generally negative slope in a selected cross-sectional profile of the brim mount.
3. The liquid container of claim 2 , wherein the fourth seal ring has a concave shape and the generally negative slope of the fourth sloped inner surface of fourth seal ring is established by a plane tangent to the fourth seal ring.
4. The liquid container of claim 3 , wherein the fourth seal ring is arranged to face toward each of the first, second, and third seal rings, the first seal ring is arranged to face toward the fourth seal ring and away from the second and third seal rings, the second seal ring is arranged to face toward the third and fourth seal rings and away from the first seal ring, and the third seal ring is arranged to face toward the first and second seal rings and away from the fourth seal ring.
5. The liquid container of claim 1 , wherein the curved shape of the fourth seal ring presents a concave surface in mating engagement with the annular outer sealing portion of the curved exterior surface of the brim of the cup.
6. The liquid container of claim 5 , wherein the lid is made of an elastic plastics material, each of the first, second, third, and fourth seal rings has an undeflected shape preparatory to mating engagement of the brim mount of the lid and the cup, and each of the first, second, third, and fourth seal rings has a different deflected shape once the brim mount of the lid is engaged with the cup to assume a mounted position on the cup, and a variation of about 0.010 inch between the undeflected and deflected shapes of each of the first, second, third, and fourth seal rings defines an interference fit established between the brim mount of the lid and the brim of the cup when the lid is mounted on the cup.
7. The liquid container of claim 6 , wherein the sloped inner surfaces of each of the first, second, and fourth seal rings has a generally positive slope and the third sloped inner surface of the third seal ring has a generally negative slope in a selected cross-sectional profile of the brim mount.
8. The liquid container of claim 1 , wherein the fourth seal ring is arranged to face toward each of the first, second, and third seal rings, the first seal ring is arranged to face toward the fourth seal ring and away from the second and third seal rings, the second seal ring is arranged to face toward the third and fourth seal rings and away from the first seal ring, and the third seal ring is arranged to face toward the first and second seal rings and away from the fourth seal ring.
9. The liquid container of claim 1 , wherein the brim of the cup includes, in series, a first brim segment coupled to the uppermost portion of the side wall, a second brim segment coupled to the first brim segment, and a third brim segment coupled to the second brim segment, the third brim segment surrounds the uppermost portion of the side wall and lies in spaced-apart relation to an exterior surface of the uppermost portion of the side wall, the second brim segment interconnects the first and third brim segments, the curved outer boundary surface is defined by, in series, a first convex curved outer surface of the first brim segment, a second convex curved outer surface of the second brim segment, and a third convex curved outer surface of the third brim segment, the annular inner sealing surface is provided on the first convex curved surface, the annular middle sealing surface is provided on the second convex curved surface, and the annular outer sealing surface is provided on the third convex curved surface.
10. The liquid container of claim 9 , wherein the brim further includes a fourth brim segment coupled to a free end of the third brim segment and formed to include an annular distal tip arranged to lie in spaced-apart relation to the exterior surface of the uppermost portion of the side wall.
11. The liquid container of claim 9 , wherein the first, second, and third convex curved outer surfaces have a common center of curvature.
12. A liquid container comprising
a cup including a brim, a floor, and a side wall extending from the brim toward the floor, the side wall including a frustoconical inner surface cooperating with the floor to form an interior liquid reservoir chamber of the cup, the brim including a curved outer boundary surface mating with an uppermost portion of the frustoconical inner surface of the side wall and extending away from the uppermost portion, the curved outer boundary surface of the brim having a rounded shape in vertical cross section that extends along a generally circular path and subtends an angle of at least 180° , the curved outer boundary surface of the brim having an annular inner sealing portion adjacent to the frustoconical inner surface of the side wall, an annular outer sealing portion away from the inner sealing portion, and an annular middle sealing portion interposed between the annular inner and outer sealing portions, and
a lid including a central closure and a brim mount coupled to the central closure and mounted on the curved outer boundary surface of the brim to retain the central closure in a position closing a mouth opening into the interior liquid reservoir chamber in the cup, the brim mount including a first seal ring having a first sloped inner surface which engages the uppermost portion of the frustoconical inner surface of the side wall to establish a first annular liquid flow barrier between the lid and the cup, a second seal ring having a second sloped inner surface which engages the annular inner sealing portion of the curved outer boundary surface of the brim to establish a second annular liquid flow barrier between the lid and the cup, a third seal ring having a third sloped inner surface which engages the annular middle sealing portion of the curved outer boundary surface of the brim to establish a third annular liquid flow barrier between the lid and the cup, and a fourth seal ring having a fourth sloped inner surface which engages the annular outer sealing portion of the curved outer boundary surface of the brim to establish a fourth annular liquid flow barrier between the lid and the cup,
wherein each of the first, second, third, and fourth sloped inner surfaces are defined relative to a horizontal axis and the first sloped inner surface of the first seal ring has a greater slope than the second sloped inner surface of the second seal ring;
wherein the second sloped inner surface of the second seal ring is steeper than the fourth sloped inner surface of the fourth seal ring;
wherein the lid includes a portion between the second seal ring and the third seal ring that is spaced apart from the brim when the second annular liquid flow barrier and the third annular liquid flow barriers are established.
13. The liquid container of claim 12 , wherein the portion that is spaced apart from the brim has a frustoconical shape.