BACKGROUND
The present disclosure generally relates to a paper drink cup lid. More specifically, the present disclosure relates to a paper drink cup lid formed of a single piece of paper and including sealing features such that spilling does not occur when the lid is installed on an annular rim of a container. Further, the paper drink cup lid includes stacking features which allow for compact storage of a plurality of lids.
During research and experimentation, the present inventors recognized a need for a drink cup lid for hot and cold beverage cups which are formed of an environmentally friendly material. Presently, there have been globally spreading bans on plastic product use. As such, there is a desire for improved containers and lids that are formed from a material that can be easily recycled or decomposes in a land fill. Paper is a leading candidate for such containers and lids.
Current paper lids in the market are not capable of producing the same positive sealing and drip/spill prevention as current plastic molded lids, insofar as paper products are not as resilient as plastic products and are not able to deform in the ways that plastic products do in order to provide robust sealing structures.
The present inventors developed an improved single-piece paper lid for a beverage container which includes two sealing features for improved sealing capabilities. In addition, the improved lid includes stacking features which aid in stacking of the lids following the lid manufacturing process.
SUMMARY
The present disclosure relates to a lid which is formed from a single piece of paper material and is configured for use with a container. The container has a sidewall and an annular rim extending around an open upper end of the container. The annular rim includes a curved outer surface formed by curling over the outer end of the container. The lid comprises a planar center portion having a diameter that is less than the diameter of the annular rim of the container. The lid further includes a nesting lug joined to the center portion and extending above the center portion. The nesting lug defines a receiving cavity that is sized to closely correspond to the curved outer surface of the annular rim. The lid further comprises a support shoulder extending radially outward from the nesting lug. The support shoulder is designed to support stacking of lids in a storage condition. The lid further includes a skirt extending from the support shoulder. In one exemplary embodiment, the skirt is oriented perpendicular to the center portion. The skirt is formed from the paper material and includes an outer wall and an inner wall perpendicular to and joined to each other. A locking skirt tab extends from an end of the inner wall at a locking angle such that the locking skirt tab extends into the receiving cavity of the nesting lug from the inner wall. The locking skirt tab is configured such that when the lid is installed on the container, the receiving cavity of the nesting lug is in contact with the outer surface of the annular rim to create a seal therebetween. In this position, the locking skirt tab engages the annular rim below an equator of the annular rim to hold the annular rim in the receiving cavity.
In this manner, the lid of the present disclosure can be formed from a single piece of paper material and is configured to seal with the annular rim of a container and hold the lid in an installed position. The paper lid of the present disclosure can thus create a fluid tight seal and is held securely in place during use of the container.
In certain embodiments, the support shoulder is annular and sized to receive the skirt of another lid in a stacked configuration.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings illustrate the best mode presently contemplated of carrying out the disclosure. In the drawings:
FIG. 1 is a perspective view of a container and a lid of the present disclosure;
FIG. 2 is an exploded view of the container and the lid;
FIG. 3 is a perspective view of the lid;
FIG. 4 is a side view of the lid;
FIG. 5 is a sectional side view of the lid initially being installed on the container;
FIG. 6 is a sectional side view of the lid being further installed on the container;
FIG. 7 is a sectional side view of the lid fully installed on the container as taken along the cross-sectional line 7-7 shown in FIG. 1; and
FIG. 8 is a sectional side view of a stack of the lids.
DETAILED DESCRIPTION
FIGS. 1-2 illustrate a lid 10 and a container 12 constructed in accordance with the present disclosure. The lid 10 is formed from a single blank of a paper product, in accordance with market shifts toward the use of more environmentally favorable materials than plastics. In accordance with an exemplary embodiment of the present disclosure, the lid 10 is formed of a single piece of paper material that is formed into the shape shown, which is favorable for ease of manufacturing. The paper material used to form the lid 10 can be coated or uncoated, depending upon the user requirements.
The container 12 is a conventional container formed from a paper material. The container 12 includes a frustoconical container sidewall 14 that increases in diameter from a lower end 13 to an upper end 15. The lower end of the container sidewall 14 is joined to and extends circumferentially about a circular base (not shown). The container sidewall 14 extends upward from the circular base and terminates at an upper end with an annular rim 16, which extends around an open upper end 15 of the container 12. As shown in FIGS. 5-7, the annular rim 16 is formed from a curled upper edge of the container sidewall in a known manner. The curled upper edge of the container sidewall has a substantially circular cross section that defines a generally open interior 39. The annular rim has an equator 17 and an outer surface 19 that engages the lid 10 when the lid is installed onto the container 12 as can be seen in FIG. 2.
Referring to FIGS. 3-4, the lid 10 is formed from a single blank of paper material that is molded to include a planar center portion 18, a nesting lug 20, and an annular support shoulder 22. The planar center portion 18 is circular and is joined at its circumferential outer edge with the nesting lug 20. During formation of the lid, the nesting lug 20 is formed such that the nesting lug 20 extends upwardly from the outer edge of the center portion 18. As shown in the section view of FIG. 5, the nesting lug 20 extends upward from the planar center portion 18 and defines an annular receiving cavity 23. The annular receiving cavity 23 is configured to closely correspond in shape to the outer surface 19 of the annular rim 16 such that the inner surface 21 of the annular receiving cavity 23 will be in contact with the outer surface 19 of the annular rim 16 when the lid 10 is installed on the container 12.
As shown in FIG. 5, the lid 10 is formed such that an annular support shoulder 22 extends radially outward from the radially outwardly most portion of the nesting lug 20. In the embodiment shown, the annular support shoulder 22 is formed to be generally co-planar with the center portion 18. However, the annular support shoulder 22 could be slightly higher or lower than the center portion 18 while still extending parallel to the center portion 18.
The lid further includes a skirt 24 that is joined to the radially outer edge of the annular support shoulder 22. As shown in FIG. 5, the skirt 24 extends downward from the annular support shoulder 22. In the embodiment shown, the skirt 24 is generally perpendicular to both the annular support shoulder 22 and the planar center portion 18. However, it is contemplated that the skirt could extend at a slight angle relative to vertical either toward or away from the outer sidewall of the container 12.
As shown in FIG. 5, the planar center portion 18 is configured to have a diameter less than a diameter of the annular rim 16 of the container 12. In this manner, when the lid 10 is received on the container 12, the radial outer edge 25 is spaced slightly inward from the container sidewall 14. As described above, the nesting lug 20 includes a curved inner surface 21 that is sized such that the annular receiving cavity 23 is configured to securely receive the annular rim 16 when the lid 10 and the container 12 are fully engaged, as shown in FIG. 7.
In the exemplary embodiment of FIG. 5, the skirt 24 is formed from a combination of an outer wall 26 and an inner wall 28. The outer wall 26 is formed from the paper blank and extends downward and generally perpendicular to the annular support shoulder 22. A fold 30 is formed at the lower end of the outer wall 26 and connects to a lower end of the inner wall 28. The fold 30 allows the skirt 24 to include both the outer wall 26 and inner wall 28 and to be formed using a single piece of paper. In one contemplated embodiment, the outer wall 26 and the inner wall 28 are in contact with each other and are joined via an adhesive. In another contemplated embodiment in which the paper material used to form the lid 10 has an outer coating, the outer coating of the inner and outer walls could be heated to create a bond between the inner and outer walls 26, 28. In another contemplated embodiment, the outer wall 26 could be formed from the single paper blank used to form the lid 10 and the inner wall 28 could be a separate strip of paper material attached or adhered to the outer wall 26. In yet another contemplated embodiment, the two surfaces can be pressed together and held mechanically using a pressure roller with a knurled surface to form an interlock between the two knurled surfaces.
As shown in FIG. 5, the inner wall 28 extends upward from the fold 30 toward an upper end 29. The portion of the inner wall 28 between the fold 30 and the upper end 29 is securely attached to the outer wall 26 to prevent separation. As shown, a locking skirt tab 32 extends from the upper end 29 of the inner wall 28. The locking skirt tab 32 is not bonded to the outer wall 26, but instead projects from the inner wall 28 inward toward the planar center portion 18 at a locking angle 0. The locking skirt tab 32 has a length which is greater than that of the annular support shoulder 22, such that an outer end 33 of the locking skirt tab 32 projects at least partially into the annular receiving cavity 23, as can be seen in FIG. 5.
When the lid 10 is to be attached to the container 12 after the container 12 is filled with liquid, a user first places the lid 10 over the open upper end of the container 12. In this position, the skirt 24 is positioned radially outward of the annular rim 16 on the top end of the container 12. Once in this position, the lid 10 is lowered down onto the container 12. During this movement, the outer surface 19 of the annular rim 16 contact an angled inner surface 40 formed on the locking skirt tab 32. The angled inner surface 40 guides the annular rim 16 into the annular receiving cavity 23 as shown in FIG. 6.
Once aligned as shown in FIG. 6, the lid 10 is then further lowered until the lid 10 is fully seated on the annular rim 16 of the container, as shown in FIG. 7. The locking angle 0 of the locking skirt tab 32 is configured to guide the annular rim 16 into the annular receiving cavity 23. The user then applies a slight increase in downward force on the lid 10 such that the annular rim 16 overcomes any resistant force from the outer end 33 of the locking skirt tab 32 and enters into the annular receiving cavity 23. Once fully engaged, as shown in FIG. 7, the inner surface 21 of the nesting lug 20 comes into contact with the outer surface 19 of the annular rim 16 over at least 90° of the outer surface 16. At this same time, the locking skirt tab 32 exerts an upward and radially inward force on the annular rim 16. In this manner, two sealing features are created between the lid 10 and the container 12. The first sealing feature is the extended surface contact between the lid 10 and the container 12. The second sealing feature is created by the force created by the locking skirt tab 32 on the annular rim 16. In the embodiment shown, the outer end 33 of the locking skirt tab 32 engages with the outer surface 19 of the annular rim 16 below the equator 17, forming the second sealing feature between the lid 10 and the container 12. In addition, the force between the locking skirt tab 32 and the annular rim 16 resists the separation between the lid 10 and the container 12.
As shown in FIG. 8, the annular support shoulder 22 is sized such that a folded lower edge 30′ of skirt 24′ of a second lid 10′ could rest upon the annular support shoulder 22. In the stacked storage condition shown in FIG. 8, four separate lids 10 are shown stacked on top of each other. This stacked configuration allows each individual lid 10 to be lifted and removed from the stack for use with a container.
Referring to FIG. 8, as previously described, the lid 10 is sized such that the annular support shoulder 22 extends radially outward from the nesting lug 20 a distance D which allows for the skirt 24′ of the second lid 10′ to be stacked thereupon, which is beneficial for packing and shipping of said lids.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
Patent Application
20240367867
