HK1073286B - Sealing and locking cup and lid - Google Patents

Description

Sealable and lockable cup and lid

Technical Field

The present invention relates to closed plastic containers and, more particularly, to containers having separate cups and lids that provide a continuous sealing and locking engagement when installed to close the container.

Background

Plastic containers are widely used for myriad packaging functions. Flexible thin-walled plastic containers are particularly attractive in food service and similar applications because of their light weight and low cost. Such containers are typically manufactured using thermoforming techniques or vacuum forming techniques. There are many plastic resins suitable for these containers, including polyethylene terephthalate (PET) and polystyrene.

When used as a beverage container or a container for other liquid food products, the cup is usually closed with a generally flat lid that snaps over a lip defining the mouth of the cup. The lid may be completely closed to prevent or inhibit leakage, or may have an open or openable area for access, such as for a straw. The snap-on cover or cover, while providing some protection against leakage and spillage, is not secure. These lids are quite easy or accidental to remove by the user and do not provide a secure closure if the container is tipped over, let alone if the container is dropped.

It would be desirable to have a container, such as a beverage cup and lid, wherein the lid can be easily installed in a manner to provide a liquid-tight seal and also to lock the lid against inadvertent opening. It would be desirable to have a sealable and lockable cup and lid wherein the lid can be easily removed by the user.

Disclosure of Invention

In accordance with the present invention, a sealed, locked and re-openable cup and lid assembly utilizes a cup having an open circular mouth defined by an upper rim, an inwardly opening locking groove below the upper rim, and a frustoconical inner wall portion extending downwardly and outwardly from the locking groove; a resilient dome sized for insertion into the open mouth of the cup and having an outer peripheral lip which is received in a locking groove in the cup with a snap fit, and a frustoconical sealing wall extending downwardly and outwardly from the peripheral lip and sealingly engaging the frustoconical inner wall portion of the cup; and, interruptions in the locking groove and in the peripheral lip, said interruptions being circumferentially spaced and rotationally alignable to enable removal of the lid.

Preferably, the locking groove is defined by a plurality of projections extending radially inwardly from the upper edge of the cup and an annular horizontal cup wall portion disposed below and spaced from the projections. The outer peripheral lip of the lid preferably includes generally horizontal upper and lower lip surfaces interconnected by a generally vertical intermediate lip surface. Each projection has lower surfaces which are generally coplanar and the peripheral lip is captured in the locking slot by the upper and lower surfaces of the lip engaging the lower surface of each projection and the horizontal wall portion, respectively. The interruptions in the peripheral lip of the lid take the form of grooves which correspond to the projections on the upper edge of the cup and enable the re-opening movement of the lid by means of the projections.

The frustoconical inner wall portion of the cup extends downwardly from the radially inner edge of the horizontal wall portion and forms therewith an edge bead having a first diameter. The frustoconical sealing wall of the cap extends downwardly from the radially inner edge of the underlying lip surface and forms therewith a second edge bead having a second diameter greater than the first diameter. The second rim bead is adapted to deflect laterally across the first rim bead as the lid is inserted and resiliently returns to provide a sealing engagement between the frustoconical sealing wall of the lid and the frustoconical portion of the cup. Preferably, the diverging angle of the frustoconical wall portion is smaller than the diverging angle of the frustoconical sealing wall.

Another embodiment of the present invention provides a sealed and locked cup and lid assembly. The assembly may include a cup having an open circular mouth defined by a cylindrical generally vertical inner first wall portion extending radially inwardly from a lower edge of the first wall portion, a plurality of locking projections circumferentially spaced about the first wall portion and extending radially inwardly from the first wall portion, each projection having a generally coplanar lower surface spaced vertically above the horizontal second wall portion, and a generally vertical inner third wall portion extending downwardly and outwardly from an inner edge of the second wall portion. The assembly may further include a resilient dome sized to fit within the open mouth of the cup and having a lip configuration with an outer periphery, and a frusto-conical, generally vertical sealing wall extending downwardly and outwardly from the radially inner edge of the lip configuration. As the lid is inserted vertically downwardly into the mouth of the cup, the lip structure is deflected inwardly by contact with the locking projection and locked between its lower surface and the horizontal second wall portion of the cup, and the sealing wall engages and seals against the third wall portion of the cup.

The lip structure may include generally horizontal upper and lower lip surfaces joined by a frusto-conical downwardly diverging connecting surface. Each locking projection may comprise a number of above-introduced surfaces extending radially inwards and downwards from the upper edge of the first wall portion. The assembly may further comprise a plurality of recesses formed in the lip structure and arranged circumferentially to correspond to the locking projections. The recesses, when aligned with the projections, provide clearance for the projections to enable removal of the lid from the cup. The cap may also include a raised central body joined to the lower edge of the closure wall along an outer peripheral edge. The assembly may also include an annular joining surface that joins the central body of the cap to the sealing wall. The lid body may include a generally frustoconical outer wall surrounding a generally flat central surface, the outer wall may include touchable indentations adapted to be engaged by a user's fingers to facilitate relative rotation of the lid and cup.

Another embodiment may include a multi-seal, multi-lock, re-openable cup and lid assembly. The assembly may include a cup having an open round mouth including an interior upper region defining a first half of a primary locking mechanism and a first half of a secondary sealing surface and an adjacent interior lower region defining a first half of a primary sealing surface and a first half of a secondary locking mechanism. The assembly may further include a resilient sealing dome insertable into the open cup mouth and having an outer peripheral lip region defining a second half of the primary locking mechanism and a second half of the secondary sealing surface and an adjacent inner lip region defining a second half of the primary sealing mechanism and a second half of the secondary locking mechanism. The lid is rotatable within the cup mouth from a fully locked and sealed position to a position which disengages the primary locking mechanism and enables manual override of the secondary locking mechanism for removal of the lid.

Another embodiment of the present invention may provide a sealed and secure container. The container may include a receptacle having an open mouth and a lid insertable into the mouth. The mouth of the receptacle may define an internal locking groove and a similar first sealing surface having a downwardly diverging negative draft angle. The lid may include an outer peripheral lip adapted to ride over an introduced surface into the locking groove and snap into locking engagement within the groove. The lip may also include a similar second sealing surface having a draft angle complementary to the negative draft angle. The first and second sealing surfaces may be arranged to sealingly engage as the lips are introduced in the groove.

Brief description of the drawings

Fig. 1 is a perspective view of a closable and lockable cup and lid assembly of the present invention.

Fig. 2 is an exploded perspective view of the assembly of fig. 1, showing the lid ready for snap-down installation in the cup mouth.

Fig. 3 is a top plan view of the cup shown in fig. 2.

Fig. 4 is a top plan view of the cover shown in fig. 2.

FIG. 5 is a top plan view of the assembled cup and lid shown in FIG. 1.

FIG. 6 is a top plan view of the cup and lid assembly of FIG. 5, further illustrating the lid rotated to a released position.

Figure 7 is a vertical cross-sectional view through the cup and lid assembly taken on line 7-7 of figure 5.

Fig. 8 is an enlarged cross-sectional detail view of a portion of fig. 7.

Fig. 9 is a further enlarged detail view of a portion of fig. 8.

Fig. 10 is an enlarged cross-sectional detail view taken on line 10-10 of fig. 2.

FIG. 11 is a cross-sectional detail view showing the resilient movement of the lid when the lid is snapped into locking engagement with the cup.

Fig. 12 is a detailed cross-sectional view taken on line 12-12 of fig. 5.

FIG. 13 is an enlarged detail view taken on line 13-13 of FIG. 6, showing vertical removal of the lid from its released position in the cup.

Detailed description of the preferred embodiments

Figure 1 shows a perspective view of an assembled cup 10 and lid 11 of the preferred embodiment of the present invention, which are preferably thermoformed from a suitable plastic material, but other molding methods may be used. In addition, any of the well-known and commonly used thermo-formable plastic resins can be used, including PET (polyethylene terephthalate) and polystyrene. It is also contemplated that foam may be utilized. Also, the gauge or material thickness may vary widely depending on a number of factors well known and commonly used in the industry.

Referring additionally to fig. 2 and 3, the cup 10 includes a lower body 12, which lower body 12, although shown in the shape of a smooth truncated cone, may likewise be slotted, ribbed, or any of a myriad of shapes and designs that are producible in conventional hot forming techniques. The cup has an open circular mouth defined by a circular upper flange 14, said upper flange 14 ending outwardly with a finished edge 15. The flange 14 defines an upper edge of a cylindrical and generally vertical inner first wall portion 16, said first wall portion 16 being joined at its lower edge by an annular generally horizontal second wall portion 17, said second wall portion 17 extending radially inwardly from the vertical first wall portion 16. The vertical first wall portion 16 is further provided with a series of circumferentially spaced locking projections 18, each locking projection 18 being inclined inwardly and downwardly from the flange 14 to provide a lead-in 20, the function of which will be explained below, each locking projection 18 having a generally flat lower surface 21, the flat lower surfaces 21 being vertically spaced above the horizontal second wall portion 17 and being generally in the same plane. The lower surface 21 of the projection 18, the vertical first wall portion 16 and the horizontal second wall portion 17 together define a locking slot 22 for the cover 11.

Joined to and extending downwardly from the inner edge of the second wall portion 17 is a generally vertical inner third wall portion 23. The circular edge defining the junction between the second and third wall parts 17 and 23 defines an edge bead 24. The third wall part 23 has a truncated cone shape which expands outwards in the downward direction. The angle of inclination or divergence of the wall portion 23 may be, for example, about 1.5 deg., but may vary widely depending on the size and shape of the cup and the lid 11 fitted to each other. A horizontal fourth wall portion 25 joins the lower edge of the third wall portion 23 with the cup body 12.

Referring additionally to fig. 4-7 and 10, the lid 11 has a central body 26 and a compound peripheral lip 27, which compound peripheral lip 27 engages the mouth of the cup 10 to lock the lid in place and provide a liquid-tight seal. The lip 27 comprises an outermost upper lip surface 27 and a horizontal lower lip surface 30, said upper lip surface 27 and lower lip surface 30 being interconnected by a generally vertical intermediate surface 31. The inner edge of the horizontal lower lip surface 30 is joined to a frustoconical generally vertical sealing wall 32, which vertical sealing wall 32 extends downwardly and flares outwardly. The angle of inclination or divergence of the sealing wall 32 may be, for example, 3 deg. which is slightly larger than the angle of inclination of the frustoconical third wall portion 23 of the cup, the lower edge of the sealing wall 32 being connected to the lid body 26 by an annular connecting surface 33. The circular engagement between the frustoconical sealing wall 32 and the annular connecting surface 33 defines an outer edge bead 34.

When it is desired to secure the lid 11 to the cup 10, the lid is placed in the mouth 13 (see FIG. 10) and pressed vertically downward. The composite peripheral lip formation 27 has a diameter greater than the minimum diameter defined by the locking projection 18, which locking projection 18 extends inwardly from the upper first wall portion 16 of the cup. Thus, when the rounded edges 29 of the engagement surfaces 30 and 31 clear the lead-in surfaces 20 of the locking projections, downward movement of the lid will cause resilient inward deflection of the lip arrangement 27, as shown in figure 11. Since the cup is typically made of a heavier gauge material and is more rigid, the primary elastic deflection occurs in the lid. However, some inherent outward deflection of the spout 13 may also occur. When the outermost edge of the upper lip surface 28 reaches the lower surface 21 of the locking projection, the entire lip 27 snaps into the locking groove 22, which locking groove 22 is dimensioned so that the upper lip surface 28 bears against the lower surface 21 of the respective projection and the lower lip surface 30 bears against the horizontal second wall portion 17 of the cup. At the bottom of the lid 11, the outer edge bead 34 contacts the inner edge bead 24 at the top of the truncated cone shaped third wall part 23 of the cup, simultaneously with the downward movement of the lid over the lead-in surface of the locking projection 18. The lid outer edge bead 34 has a slightly larger diameter than the cup inner edge bead 24. The resilient deflection of the lid lip 27 causes the outer edge bead 34 to pass over the inner edge bead and move with a secondary snap-fit movement under the inner edge bead while bringing the lid sealing wall 32 into sealing contact with the wall portion 23.

The interconnection of the lid 11 with the cup 10 described above provides a positive primary locking of the lid lip structure 27 in the cup locking groove 22, a primary liquid-tight seal between the cup frustoconical wall portion 23 and the lid frustoconical sealing wall 32, a secondary liquid seal between the lid lower lip surface 30 and the cup horizontal wall portion 17, and a secondary locking formed as the frustoconical sealing surfaces 23 and 32 enter the engagement cup with the inner rim bead 24 passing over the lid outer rim bead 34.

As can best be seen in fig. 5 and 8, the secure primary locking of the lid lip 27 in the cup locking groove 22 virtually precludes removal of the lid unless the lid is permanently deformed or torn. The locking and liquid-tight seal can withstand a considerable drop impact with the cup full without dislodging the lid or allowing the contents to leak.

However, since it may be desirable to remove the lid from the cup, a release or reopening feature is also provided. The peripheral lip 27 of the lid is provided with a plurality of recesses 35, said recesses 35 being circumferentially spaced to correspond to the positions of the cup locking projections 18. Each groove 35 is defined by a continuously grooved portion of the upper lip surface 28 and the intermediate connecting surface 31. Thus, each groove 35 extends partially into the underlying horizontal lip surface 30. When each recess 35 is rotationally aligned with locking projection 18 as shown in fig. 6 and 13, lid 11 can be gripped and lifted vertically, said lid 11 being constrained only by the interference fit between frustoconical sealing surfaces 23 and 32. However, as the outer edge bead 34 in the lid deflects inwardly and past the inner edge bead 24 in the cup, the vertical lifting movement of the lid overcomes the secondary lock. It should be noted that the primary seal between the sealing surfaces 23 and 32 remains fully operational despite the alignment of the recesses 35 with the locking projections 18 when the lid is held in the closed position, and that the secondary frictional locking contact between these surfaces also provides good protection against accidental removal of the lid.

In the presently preferred embodiment of the cover 11, the body 26 is bulged and has a generally flat top portion 37 and a downwardly inclined generally frusto-conical outer wall 38, said outer wall 38 being joined at its lower edge to the annular connecting face 33. The outer wall 38 of the lid is provided with a number of accessible recesses 40 for contact by a user's thumb and finger to enable easy rotation of the detent 35 in the lid with the locking projection 18 for removal of the lid. It will be apparent that the cover may be provided with other tactile means to facilitate removal of the cover, including a depression in the flat top surface 37 or a raised handle also formed in that surface. Similarly, caps having other body shapes may be utilized.

The lid 11 is easily snapped into full locking and sealing engagement with the cup without first aligning the recess 35 in the lid with the locking protrusion 18 in the cup, as shown in fig. 2. Thus, there is no need to rotationally pre-align the parts with one another and, when so mounted, to snap the lip 27 directly under the projections and into the locking slot 22, there is no need to rotate the lid into the cup to ensure that the lid is locked into place. The diameter of the horizontal upper lip surface 28 of the lid is slightly smaller than the inner diameter of the vertical first wall portion 16 of the cup. This ensures that the primary seal between the frustoconical cup surface 23 and the frustoconical cover surface 32 is not disturbed and enables the cover to be rotated within the cup without excessive frictional engagement between the edge of the lip surface 28 and the cover wall 16. Thus, it can be seen that the primary sliding contact during rotation of the lid to the release position is between the sealing surfaces 23 and 32.

As mentioned above, the closure wall 32 in the lid has a draft angle, the draft angle of the closure wall 32 being slightly greater than the draft angle of the closure wall portion 23 of the cup. This difference in draft angle increases the spring force between the outer edge bead 34 and the cup sealing wall 23 to increase the seal and ensure that any surface irregularities do not break the seal. Although some direct face-to-face contact between the frustoconical cup wall portion 23 and the frustoconical lip seal wall 32 is possible due to the inherent resiliency of the parts, the primary seal is ensured by the greater slope angle of the lid wall 32 and the primary sealing contact is ensured by the outer edge bead 34.

By providing a lid 11 that is contained entirely within the mouth 13 of the cup 10 when installed, there is no free lid lip edge that can inadvertently engage or accidentally bump over to dislodge the lid, a common problem with conventional cup lids that stack onto the outside of the cup flange. The primary locking and sealing features provide excellent protection against leakage and lid dislodgment if the cup is tripped, bumped or dropped. An inherent benefit of the snap locking of lip 27 in locking groove 22 is that it creates an audible "click". As a result, the person inserting the lid into locking engagement with the cup does not have to look at it himself when installing the lid to ensure it is locked in place. The audible click is a clear indication of a locked closure while providing a sense of security to service personnel and customers.

Claims (17)

1. A sealed, locked and reopenable cup and lid assembly comprising:

a cup having an open circular mouth defined by an upper rim, a locking groove opening inwardly below the upper rim, and a frustoconical inner wall portion extending downwardly and outwardly from the locking groove;

a resilient dome sized for insertion into the open cup mouth and having an outer peripheral lip snap-fitted into said locking groove and a frustoconical sealing wall extending downwardly and outwardly from said lip and sealingly contacting said frustoconical inner wall portion; and

circumferentially spaced and rotatably aligned interruptions in the locking groove and the lip that allow removal of the lid when the interruptions in the locking groove and the lip are aligned.

2. The assembly of claim 1 wherein said locking slot includes a plurality of projections extending radially inwardly from the upper rim of the cup and an annular horizontal wall portion below and spaced from the projections.

3. The assembly of claim 2 wherein the outer peripheral lip of the cover includes horizontal upper and lower lip surfaces interconnected by a vertical intermediate lip surface;

each bulge comprises a lower surface on the same plane; and

the lip is locked in the locking groove by the upper and lower surfaces of the lip contacting the protrusion and the horizontal cup wall portion, respectively.

4. The assembly of claim 3 wherein said discontinuity in said lip of said lid comprises a plurality of recesses, said recesses corresponding to projections on the upper rim of the cup, said upper rim of the cup allowing for reopening movement of the lid by the projections.

5. The assembly of claim 3, wherein:

a frustoconical inner wall portion of the cup extending downwardly from the radially inner edge of the horizontal cup wall portion and forming therewith a first edge bead having a first diameter; and

a frustoconical sealing wall extends downwardly from the radially inner edge of the lower lip surface and forms therewith a second edge bead having a second diameter greater than the first diameter.

6. An assembly as set forth in claim 5 wherein said second edge bead is adapted to laterally deflect over said first edge bead upon insertion of the cap and to resiliently return to provide sealing engagement between said frustoconical sealing wall and said frustoconical inner wall portion.

7. The assembly of claim 6, wherein the angle of divergence of the frustoconical inner wall portion is less than the angle of divergence of the frustoconical sealing wall.

8. A sealed and locked cup and lid assembly comprising:

a cup, said cup having: an open round mouth defined by a cylindrical vertical inner first wall portion; an annular horizontal second wall portion extending radially inwardly from a lower edge of said first wall portion; a plurality of locking projections circumferentially spaced about and extending radially inwardly from said first wall portion, said projections having coplanar lower surfaces vertically spaced above said horizontal second wall portion; and a frusto-conical vertical inner third wall portion extending downwardly and diverging outwardly from the inner edge of said second wall portion; and

a resilient dome sized to fit within an open mouth of a cup and having an outer peripheral lip structure and a frustoconical vertical sealing wall extending downwardly and outwardly from a radially inner edge of said lip structure;

thus, as the lid is inserted vertically downwardly into the mouth of the cup, the lip structure is deflected inwardly by contact with the locking projection and locked between its lower surface and the horizontal second wall portion of the cup, and the sealing wall engages and seals with the third wall portion of the cup.

9. The assembly of claim 8 wherein said lip structure includes horizontal upper and lower lip surfaces joined by a frusto-conical downwardly diverging connecting surface.

10. The assembly of claim 9 wherein said locking projection includes upper lead-in surfaces extending radially inwardly and downwardly from an upper edge of said first wall portion.

11. The assembly of claim 8, further comprising a plurality of recesses formed in said lip structure and positioned circumferentially corresponding to said locking projections, said recesses providing clearance for said projections when aligned with said projections to allow removal of the lid from the cup.

12. The assembly of claim 11 wherein said lip structure includes horizontal upper and lower lip surfaces joined by a frusto-conical downwardly diverging connecting surface and said recess includes a continuously grooved portion of the upper lip surface and said connecting surface.

13. The assembly of claim 8 wherein said cap further comprises a raised central body joined to the lower edge of the closure wall along an outer peripheral edge.

14. The assembly of claim 13, further comprising an annular joining surface joining the central body of the cap to the sealing wall.

15. The assembly of claim 13, wherein said cap body includes a frustoconical outer wall surrounding a flat central surface.

16. The assembly of claim 15, wherein said outer wall includes a plurality of touchable indentations, said indentations adapted to engage a user's fingers to facilitate relative rotation of the lid with respect to the cup.

17. A sealed and fixed container comprising a receptacle having an open mouth and a cap insertable into said mouth, the mouth of the receptacle defining an internal locking groove at the opening and an adjacent first sealing surface, said first sealing surface having a downwardly diverging negative profile angle, the cap having a peripheral lip adapted to ride over an introduction surface into said locking groove and adapted to snap into locking engagement within said groove and an adjacent second sealing surface having a profile angle complementary to said negative profile angle, said first and second sealing surfaces being arranged to sealingly engage as said lips snap into said groove.