STACKABLE CUP

Abstract

A sippy cup stacking system comprising multiple substantially identical sippy cups having sippy spout lids that can be mated with the bottom of a first cup while attached to the top of a second cup. Each cup includes a bottom with an annular recess containing a central locking plug capable of mating with a central locking stem protruding from a lid on another cup. The sippy spout on each lid is radially offset from the locking stem and fits into and can move circumferentially in the annular recess on the bottom of the cup to which it is being mated, until the spout is fully enclosed by the bottom of the mated cup.

Claims

1. A cup stacking system comprising two or more substantially identical cups with lids, said cups configured to be stacked with their respective lids secured on said cups, wherein: each cup comprises a sidewall, a top with a removable lid, and a bottom; said bottom of each cup comprises an annular recess defined between a lower bottom sidewall portion and one of a locking plug and a locking stem protruding downwardly from a center portion of said bottom of said cup within a volume bounded by said lower bottom sidewall portion, said one of a locking plug and a locking stem further coaxially aligned with a longitudinal center axis of said cup; each lid comprises the other of a locking plug and a locking stem protruding from an upper side of said lid and coaxially aligned with a longitudinal center axis of said cup, said locking stem configured to mate in removable locking fit with said locking plug; wherein, each lid while attached to the top of a second of said cups, can be lockingly mated with said bottom of a first of said cups via said locking stem removably engaging said locking plug.

2. The cup stacking system of claim 1, wherein said locking plug and said locking stem mate with a rotatable connection.

3. The cup stacking system of claim 2, wherein said locking plug and said locking stem include mating cylindrical thread form portions to mate with multiple full circumference rotations of said lid on said second cup relative to said bottom of said first cup.

4. The cup stacking system of claim 1 wherein said mating locking plug and said locking stem between said lid and said cup above it mate with a frictional engagement so as to click together with a push and securely hold said lid to said bottom of said cup above it.

5. The cup stacking system of claim 1, where each lid further comprises a spout protruding from said upper side of said lid higher than said one of said locking plug and locking stem and is radially offset outwardly from said one of said locking plug and said locking stem, said annular recess having a sufficient volume to fully receive said spout therein; and, where when said lid on said second cup is secured against said bottom of said first cup said spout on said lid is enclosed within said annular recess on said bottom of said second cup.

6. The cup stacking system of claim 5 where said locking plug protrudes downwardly from a center portion of said bottom of said cup and said locking stem protrudes upwardly from an upper side of said lid and coaxially aligned with a longitudinal center axis of said cup.

7. The cup stacking system of claim 6, wherein said locking plug and said locking stein, mate with a rotatable connection.

8. The cup stacking system of claim 6 wherein said mating locking plug and said locking stem between said lid and said cup above it mate with a frictional engagement so as to click together with a push and securely hold said lid to said bottom of said cup above it.

9. The cup stacking system of claim 1, further comprising a removable handle attachment comprising a generally flat disc body having a diameter equal to or greater than a cup bottom diameter, a pair of upwardly-extending handles extending from opposing sides of said disc body, and another of said locking plug and said locking stem centered on and protruding from an upper side of said body a distance less than said handles, said locking stem and said locking plug removably mating with one another to secure said disc body against said bottom of said cup and said handles are extended above said bottom of said cup spaced outwardly from said cup sidewall.

10. The cup stacking system of claim 9, wherein said mating locking plug and said locking stem between said handle disc body and said bottom of said cup above said handle disc body mate with a rotatable connection.

11. The s cup stacking system of claim 9 wherein said mating locking plug and said locking stem between said handle disc body and said bottom of said cup above it mate with a frictional engagement so as to click together with a push and securely hold said handle to said bottom of said cup

12. The cup stacking system of claim 9 where said locking plug protrudes downwardly from a center portion of said bottom of said cup and said locking stem protrudes upwardly from an upper side of said lid and coaxially aligned with a longitudinal center axis of said cup; and wherein said one of a locking plug and a locking stem on said handle disc body is a locking stem protruding upwardly for mating engagement with said locking plug on said bottom of said cup above it.

13. The cup stacking system of claim 5 in which each said lid also includes a relief valve assembly made from a soft elastomeric plastic or rubber-like material comprising a first upstanding sippy spout portion which fits snugly up into said sippy spout and a second upstanding portion which fits snugly into said one of said locking plug and said locking stem which protrudes upwardly from said lid; said locking stem and said locking plug including a vent opening and said sippy spout including an opening to facilitate sucking liquid from said cup through said sippy spout on said lid; said relief valve assembly sealing said spout opening and said one of said locking stem and locking plug opening; said first and second upstanding portions of said relief valve assembly including valved openings which open to permit fluid or air flow when suction is applied to said sippy spout.

14. The cup system of claim 13 in which said relief valve assembly includes a pull tab protruding downwardly therefrom into the space below said lid, for facilitating removal of said relief valve assembly from said lid for cleaning.

15. The cup stacking system of claim 1 where said locking plug protrudes downwardly from a center portion of said bottom of said cup and said locking stem protrudes upwardly from an upper side of said lid and coaxially aligned with a longitudinal center axis of said cup.

16. The cup stacking system of claim 15, wherein said locking plug and said locking stein mate with a rotatable connection.

17. The cup stacking system of claim 16 wherein said mating locking plug and said locking stem between said lid and said cup above it mate with a frictional engagement so as to click together with a push and securely hold said lid to said bottom of said cup above it.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is a perspective view of multiple lidded cups according to one embodiment of the invention, mated in a stack, with a portion of the interface of two cups cut away to show an example locking structure.

[0021] FIG. 1A is similar to FIG. 1 but shows the upper and lower cups in the stack exploded from the middle cup, and their respective lids exploded from the cups.

[0022] FIG. 2 is a cutaway view of one of the cups with attached lid from FIG. 1, taken from an upper (lid) perspective.

[0023] FIG. 3 is a cutaway view of one of the cups with attached lid from FIG. 1, taken from a lower (cup bottom) perspective.

[0024] FIG. 4 is a sectional side elevation view of the stacked cups of FIG. 1.

[0025] FIG. 5 is a cutaway side perspective view of the stacked cups of FIG. 1.

[0026] FIG. 6 is a perspective view of an underside of a lid from one of the cups in FIG. 1, with a relief valve assembly that can be mated with the central locking plug and sippy spout portions of the lid.

[0027] FIG. 7 is an upper perspective view of the lid of FIG. 6 and a cup, partially cutaway to show the relief valve structure inserted in the sippy spout and locking stem.

DETAILED DESCRIPTION

[0028] Referring first to FIGS. 1 and 1A, a stacking sippy cup system is shown in exemplary form in order to teach how to make and use the claimed invention. The system comprises two or more sippy cups 10, each cup having a removable lid 30 capable of mating in secure fashion not only with its underlying cup 10, but also with the bottom of another cup 10 above it to form a stack 100 of multiple lid-covered cups 10. The upper surface 32 of each lid 30 has a protruding sippy spout 34 of generally known form, radially offset from the center of the lid, with one or more fluid openings 35 of known type that limits the drinking flow of fluid from the cup. Each lid 30 also includes a locking stem 36 protruding from the radial center of the upper surface of the lid, in the illustrated example with cylindrically-mating threads 36a formed on the exterior of the stem, and with an optional pressure relief vent opening 37.

[0029] In the illustrated example of FIG. 1, the bottom of the bottom-most cup 10 in the stack 100 is mated to a handle attachment 130 with handles 132, rather than a lid. Handle attachment 130 attaches to the bottom of a cup 10 in the same manner as one of the lids 30, i.e., via a screw-on locking stem 136 essentially identical to stem 36 on lid 30 except for the lack of a pressure relief opening.

[0030] Cups 10 and lids 30 (and handle attachment 130) may be formed from any known plastic material suitable for use as a drinking cup, for example molded from BPA-free polyethylene or polypropylene. It would be possible to form cups 10 and lids 30 from other materials used for drinking cups, such as metal, but a modern durable lightweight plastic is preferred. The size of the cups may vary, but dimensions suitable for 8-16 oz. cups would be typical.

[0031] Each cup 10 has an open upper end or top 12, a sidewall 14, and a lower end or bottom 16. The top of cup 10 includes connecting structure such as threads 12a for mating in generally fluid-tight fashion with corresponding connecting structure on lid 30 in known manner, for example mating threads formed on the inside of the lid sidewall 31. The top 12 and bottom 16 of the cup and the lid 30 are preferably cylindrical as in the illustrated example, with cylindrical mating thread-forms connecting the lid to the cup, although other shapes and lid-cup connecting structures are possible.

[0032] Referring to FIGS. 1 through 3, the bottom 16 of cup 10 includes an outer vertical wall portion 16a extending downwardly beyond the interior transverse bottom surface 16b of the cup. The bottom outer wall 16a defines in part and surrounds an annular cavity 18 (FIGS. 2 and 3) formed around a radially centered locking plug 20 protruding from the bottom wall 16b no farther (and preferably less) than the lower edge of bottom outer wall 16a. The locking plug 20 in the illustrated example is female, configured with a socket to receive a male locking stem 36 on a lid 30. Annular cavity 18 is deep enough to receive the sippy spout 34 on a lid 30 when the locking stem 36 on the lid is mated with the locking plug 20 on the bottom of the cup.

[0033] While the locking stem 36 is shown as a male connecting portion, and the locking plug 20 is shown as a female connecting portion, these could be reversed, with a female socket on the locking stem 36 and plug 20 configured as a male portion. While cylindrically-mating thread forms requiring multiple rotations for connection are illustrated and currently preferred, other rotating or twist connection structures such as known types of twist-lock or bayonet style connections that lock together with less than a full circumferential rotation are possible in place of the illustrated threads that require multiple rotations of the mating cup. Also, non-rotating or linear mechanical, magnetic, frictional, or other connections between locking plug 20 and locking stem 36 are possible, including but not limited to frictional detents or annular beads located on the respective mating stem and plug portions to click together with a push and securely hold the cup underneath to the cup above. And while the annular recess in the bottom of each cup is especially useful for accommodating a rotating locking connection as illustrated, with any kind of connecting structure the recess allows the lid underneath to be mated with the bottom of the cup above in any circumferential orientation and with a degree of circumferential movement that may assist with making the connection.

[0034] The diameter of lid 30 is sized to form a snug, preferably sealing fit between an outer surface portion of the lid and the bottom outer wall 16a of the cup above it. For example, a beveled outer edge 31b of the lid can mate flush with the lower edge of bottom wall 16a when the lid is fully mated with the bottom of the cup, i.e., when locking stem 36 is fully mated with locking plug 20, in order to fully enclose and seal the nippy spout on the lid within the bottom of the cup above it. The diameter of the plate- or ring-like flat body portion 134 of handle attachment 130 is likewise sized to fit snugly against the lower edge 16b of bottom wall 16a when the handle attachment is fully mated with the bottom of the cup.

[0035] The relative heights and depths of the locking stem 36, locking plug 20, annular cavity 18, and sippy spout 34 may be sized so that some or all of them provide a positive vertical stop against each other's surfaces when the lid 30 on an underneath cup is fully mated with the bottom 16 of the cup 10 above it. This is perhaps easiest to picture in FIGS. 4 and 5.

[0036] Each cup 10 may also include a relief valve assembly 40 of known type, for example made from a soft elastomeric plastic or rubber-like material comprising one or more upstanding plug portions 42, 44 that fit snugly up into the interiors of the sippy spout 34 and the locking stem 36. Relief valve assembly 40 seals the spout and locking stem openings 35, 37 relative to any liquid in the cup, except for metered flow openings 42a and 44a that allow some fluid and air flow, respectively, to assist with drinking from spout 34. Relief valve assembly 40 may include a pull tab 46 to help remove assembly 40 from the lid 30 for cleaning.

[0037] FIGS. 2-5 show the annular nature of recess 18 in the bottom 16 of cup 10, and in particular the clearance provided in the bottom of the cup for the radially-offset sippy spout 34 of a lid 30 mated with the bottom of the cup. Sippy spout 34 may take different known configurations and may be open at the top or may be capped with a removable/openable covering or closure mechanism of known type. Whatever the size of the spout, however, annular recess 18 provides sufficient clearance both radially and vertically to receive spout 34 as locking stem 36 on lid 30 is mated with locking plug 20 on cup 10. As locking stem 36 is mated in rotating threaded fashion with locking plug 20, recess 18 allows spout 34 to rotate around the locking plug 20 within the outer bottom wall portion 16a of the bottom 16 of the cup.

[0038] Further as shown in FIGS. 2-5, the interior wall 34a of sippy spout 34 is preferably angled, narrowing upwardly toward the tip of the spout. The outer wall or surface 20c of locking plug 20 in the bottom of the cup may be correspondingly sized and tapered (narrowing downwardly from the base of the plug at cup bottom surface 16b) for better clearance between the spout and the plug.

[0039] Locking plug 20 may be formed in a way relative to cup transverse bottom surface 16b to create a central tapered well 16c in the bottom center of the interior of the cup, creating a small fluid volume extending below the generally flat transverse interior bottom wall 16b.

[0040] It will finally be understood that the disclosed embodiments represent presently preferred examples of how to make and use the invention but are intended to enable rather than limit the invention. Variations and modifications of the illustrated examples in the foregoing written specification and drawings may be possible without departing from the scope of the invention. It should further be understood that to the extent the term invention is used in the written specification, it is not to be construed as a limiting term as to number of claimed or disclosed inventions or discoveries or the scope of any such invention or discovery, but as a term which has long been used to describe new and useful improvements in science and the useful arts. The scope of the invention supported by the above disclosure should accordingly be construed within the scope of what it teaches and suggests to those skilled in the art, and within the scope of any claims that the above disclosure supports in this provisional application or in any non-provisional application claiming priority to this provisional application.