U.S. patent application number 10/819411 was filed with the patent office on 2005-10-13 for leak resistant lid assembly for a beverage container.
Invention is credited to Brown, William L., Crowell, Timothy E., Haase, Sarah M..
Application Number | 20050224505 10/819411 |
Document ID | / |
Family ID | 35059509 |
Filed Date | 2005-10-13 |
United States Patent
Application |
20050224505 |
Kind Code |
A1 |
Brown, William L. ; et
al. |
October 13, 2005 |
Leak resistant lid assembly for a beverage container
Abstract
A leak resistant lid for a beverage container is formed with a
depending skirt portion having one or more progressively decreasing
diameter rings between a lower extremity and a sealing channel
adapted to fit over the rim bead of the container. An inner wall of
the channel extends downwardly inside the inner surface of the side
wall of the container in a plug fit relationship. The relatively
deep inside plug fit provides added surface area contact for
sealing the interface between the lid and the container. An
elevated and rigid central plateau supports a drinking orifice and
is connected to the inner wall of the channel by a reinforced,
rigid flange or web which maintains the channel and its inner wall
in leak resistant relationship with the rim bead and container
wall.
Inventors: |
Brown, William L.; (Mason,
OH) ; Crowell, Timothy E.; (West Bend, WI) ;
Haase, Sarah M.; (Milwaukee, WI) |
Correspondence
Address: |
INTERNATIONAL PAPER COMPANY
6285 TRI-RIDGE BOULEVARD
LOVELAND
OH
45140
US
|
Family ID: |
35059509 |
Appl. No.: |
10/819411 |
Filed: |
April 7, 2004 |
Current U.S.
Class: |
220/792 ;
220/713 |
Current CPC
Class: |
B65D 43/0208 20130101;
B65D 2543/00046 20130101; B65D 2543/00518 20130101; B65D 2543/00638
20130101; B65D 2543/00564 20130101; B65D 2543/00092 20130101; B65D
2543/00537 20130101; B65D 2543/00296 20130101; B65D 2543/00731
20130101 |
Class at
Publication: |
220/792 ;
220/713 |
International
Class: |
B65D 041/18; A47G
019/22 |
Claims
1. A lid for closing a container, the container having a generally
circular rim and an outwardly projecting annular bead on said rim,
and a downwardly extending wall portion having an inner surface
adapted for containing liquid, the lid comprising: a central web;
an upstanding generally annular plateau surrounding said central
web, said plateau having an outer wall extending downwardly so that
an extremity of said wall is within said rim of said container when
said lid is attached to said container; a reinforcing web extending
from said lowest extremity of said outer wall of said plateau to a
radially inner wall of an annular sealing channel; said sealing
channel being adapted for engagement with said rim of said
container; said radially inner wall of said sealing channel having
a downwardly extending wall portion adapted for engaging said inner
surface of said container, and a curvilinear channel portion
extending from said downwardly extending wall portion so as to
engage said annular bead on said rim in a sealing relationship.
2. A lid according to claim 1 and further comprising: an annular
skirt portion extending downwardly from said channel portion
outside of said bead on said rim.
3. A lid according to claim 1 wherein; said reinforcing web
comprises an array of projections at a surface of said web for
stiffening said web.
4. A lid according to claim 1 wherein: said outer wall of said
plateau has a lower extremity positioned to extend below said
annular bead of the container and an upper extremity extending
above said rim of the container when said lid is positioned on a
container for use.
5. A lid according to claim 1 wherein: said central web, said
annular plateau and said reinforcing web form a substantially rigid
annular rim along a lower edge of said sealing channel; and said
lower inside edge of said sealing channel is dimensioned to provide
an interference plug fit with said inner surface of said wall
portion of said container.
6. A lid according to claim 5 wherein: said interference fit is
associated with a diametric dimension of approximately the
thickness of said wall of said container.
7. A lid according to claim 6 wherein: said diametric dimension is
of the order of 0.04 inches.
8. A lid according to claim 3 wherein: said projections are
disposed along adjacent radial lines.
9. A lid according to claim 8 wherein: said projections are rib
shaped.
10. A lid according to claim 8 wherein: said projections are dimple
shaped.
11. A lid adapted for use in connection with a container for
liquids comprising: a generally annular sealing channel having
inner and outer walls; an annular skirt extending downwardly from
said outer wall of said channel; a reinforcing flange extending
radially inwardly from said inner wall of said annular channel
towards the center of said lid and having radially disposed
reinforcing projections extending from a surface thereof; an
annular upstanding wall extending from a radially inner extremity
of said flange to a generally annular plateau; a central web
extending radially inwardly from said plateau to form a
substantially closed lid, wherein said inner wall of said channel
is dimensioned for a plug interference fit within the inner wall of
a container with which it is intended for use.
12. A lid according to claim 11 for use in connection with a
container having an annular rim bead at the top edge thereof
wherein: an outer wall of said plateau has a lower extremity
positioned to extend below said annular bead of the container and
an upper extremity extending above said rim of the container when
said lid is positioned on a container for use.
13. A lid according to claim 12 wherein: said central web, said
annular plateau and said reinforcing web form a substantially rigid
annular rim along a lower edge of said sealing channel; and said
lower inside edge of said sealing channel is dimensioned to provide
an interference plug fit with said inner surface of said wall
portion of said container.
14. A lid according to claim 13 wherein: said interference fit is
associated with a diametric dimension of approximately the
thickness of said wall of said container
15. A lid according to claim 14 wherein: said diametric dimension
is of the order of 0.04 inches.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
FIELD OF THE INVENTION
[0003] This invention relates to containers for liquids, to lids
for such containers and, more specifically, to replaceable, leak
resistant lids for containers or cups having a generally
cylindrical or frusto-conical shape.
[0004] Although the invention described herein is particularly
suitable for application to beverage drinking cups, a person
skilled in this art readily may apply the invention to other
similar containers which require a removable, leak resistant
lid.
SUMMARY OF THE INVENTION
[0005] In accordance with the present invention, a highly leak
resistant "sipper" lid suitable for paper beverage cups is
provided. The unintentional passage of liquid between the mating
surfaces of a cup and a lid is effectively suppressed. This feature
meets consumer expectations in that, when consumers purchase drinks
in cups with lids applied, they expect the cup/lid combination to
prevent leakage between the mating surfaces when the cup is
inclined for drinking. However, many designs fall short of this
important objective.
[0006] A particular problem arises in connection with some
containers which are formed such that each of their side wall and
rim are formed into a closed vessel by overlapping the material
(relatively thick paper) at a joint or seam. When a lid having a
spout or orifice for drinking is placed over such a thick seam,
there is a tendency for leakage out of the lid in that area of the
rim. One approach to this problem has been to attempt to educate
customers to orient the lid on the cup so that the drinking orifice
is diametrically opposite the joint or seam, thereby placing the
leakprone area above the level of liquid in the cup when drinking
is in progress. This approach is not entirely successful since many
users do not receive, understand or remember this instruction.
[0007] In accordance with one aspect of the present invention, a
lid adapted for use in connection with a container for liquids
comprises a generally annular mounting ring or channel for sealably
engaging an upper edge or rim of a container, an annular skirt
extending downwardly from the mounting ring over an outer wall of
the container, an annular flange extending radially inwardly from
the mounting ring and an annular, upstanding wall extending from a
radially inner extremity of the flange to a generally annular
plateau. The plateau, in turn, is connected to a central region
which serves to form a closed lid structure. A drinking orifice
typically is provided in the plateau region.
[0008] The annular mounting ring is complementarily configured with
respect to the container with which it is to be combined so as to
provide a plug fit against the inner wall of the container and to
engage the rim thereof to provide a desired leak resistant seal.
These and other objects and advantages of the present invention
will become apparent from the following detailed description in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
[0009] In the drawings:
[0010] FIG. 1 is a front elevation view of a cup or container
having one form of a lid in accordance with an embodiment of this
invention;
[0011] FIG. 2a is a plan view of a particular lid according to a
preferred embodiment of the invention;
[0012] FIG. 2b is a cross-sectional view taken along the line B-B'
of FIG. 2a;
[0013] FIG. 2c is a partial cross sectional view showing a stack of
two of the lids of FIG. 2a;
[0014] FIG. 3 is a partial, enlarged cross-sectional view of the
portion of the lid enclosed in a dashed circle in FIG. 2b, showing
relationships between the lid and container;
[0015] FIG. 4 is a partially cut away elevation view of one type of
standard container suitable for use in connection with this
invention;
[0016] FIGS. 5a, 5b and 5c are views similar to those shown in
FIGS. 2a, 2b and 2c of a second embodiment of the invention;
and
[0017] FIG. 6 is a partial, enlarged cross-sectional view of the
portion of the lid enclosed in a dashed circle in FIG. 5b.
DESCRIPTION OF ILLUSTRATIVE EMBODIMENT OF THE INVENTION
[0018] Referring to FIG. 1, a typical container or cup assembly 10
suitable for beverages and being formed from paper, plastic,
plastic foam or the like, in a generally cylindrical or
frusto-conical shape, is shown. A lid 12 constructed according to
the present invention is shown sealably mounted at the top of
container 10. Lid 12 (other forms of which are shown in greater
detail in others of the figures) preferably is produced by
thermoforming a thin, flat sheet of clear or opaque (black, white
or colored) plastic such as polystyrene onto a lid mold to form the
desired lid shape which will be explained below. The lid may also
be formed by injection molding while maintaining the desired
properties and characteristics as set forth hereinafter. The
thickness of the plastic for the lid typically is about 0. 017
inches in its finished form.
[0019] The container 10 typically is a paper cup suitable for hot
or cold beverages and will be referred to hereinafter as cup 10. As
is customary, such cups have a substantially tubular (circular
cross section) bead 14 (see FIG. 4) formed at their upper edge and
extending radially outwardly from the generally cylindrical or
conical upright wall 16 of the cup.
[0020] As can be seen in FIGS. 2a-3, lid 12 comprises a generally
inverted U-shaped sealing channel 18 having a cross-section (FIG.
3) with an interior wall 22 of generally the same curvilinear to
straight shape as the combination of the outer extremity of bead 14
and the upper end of the wall 16 of cup 10. More specifically, on
lid 12, the outer (maximum diameter) portion 20 of channel 18 is
generally tubular in shape and it transitions smoothly into a
substantially vertical, straight, inclined inner wall member 24
which is outwardly inclined at its upper end. Wall member 24 is
inclined at substantially the same angle A (e. g. 6.25 degrees) as
the wall of the cooperating cup 10. Inner wall member 24 is adapted
to extend downwardly inside wall 16 of cup 10 in a "plug fit"
relationship.
[0021] A negative clearance or plug interference fit such as 0.04
inches for a cup 10 having a specified maximum outside bead
diameter of 3.54 inches is provided between the inner wall 24 of
channel 18 and the inner surface 16' of wall 16 of cup 10. This
deep inside plug fit provides the desired surface area contact for
sealing the interface between the adjacent surfaces of lid 12 and
cup 10.
[0022] In addition, at a sloped transition region 28 between a
lower extremity of channel 18 and an upper extremity of a skirt 32,
an undercut or reentrant wall 30 is provided which has an minimum
inner wall diameter, for example, 0.05 inches less than the maximum
inner wall diameter 30 of channel 18 as best seen in FIG. 3 ("0.025
UNDERCUT").
[0023] A lowermost inner corner 26 of inclined inner wall 24 is
shown having a diameter of 3.25 inches. As shown in FIG. 4, the
outermost diameter of the rim bead 14 for a corresponding cup 10
has a nominal value of 3.54 inches. The bead 14 itself is specified
as having a nominal diameter of 0.14 inches. It can therefore be
seen that the maximum opening at the top of cup 10 (measured at the
uppermost point on rim bead 14 where the inner surface 16' of cup
wall 16 begins to slope downward and inwardly) is nominally 3.54
inches minus 0.14 inches or 3.50 inches. The lowermost inner corner
26 of inclined wall 24 of channel member 18 therefore will fit into
the top of rim bead 14 with a clearance of about 0.07 inch on each
side (diameter is nominally 0.14 inches smaller).
[0024] The inward slope of the inner surface 16' of wall 16 (for
example, nominally 6.25 degrees in some cups and 5 degrees in
others), and the dimensions of cup wall 16 and inclined wall 24 of
channel 18, are arranged so that the lowermost inner corner 26 of
channel 18 will come into contact with the inner surface 16' of cup
wall 16 before the lid 12 is fully seated on the top of rim bead
14. In addition, the largest unstressed diameter inside the
curvilinear portion 22 of channel 18 is typically selected to be
3.50 inches, a dimension approximately 0.04 inches less than the
nominal largest diameter of rim bead 14. This arrangement provides
a negative (or interference) snap fit of the channel 18 over rim
bead 14. Thus, as the lid 12 is placed on cup 10, the lower edge of
a skirt region 32 (e.g. 3.55 inch diameter) of lid 12 passes over
rim band 14 until sloped transition region 28 engages rim band
14.
[0025] Skirt region 32 is then bowed outwardly as pressure is
applied to the top of lid 12 until undercut 30 snaps over rim band
14 of the cup 10. As additional pressure is applied around the
entire top of lid 12, the inner surface 22 of the upper curvilinear
region of channel 18 seats along the top of rim bead 14 and the
lowermost corner 26 of inclined wall 24, along with a portion of
wall 24, forms an interference or plug fit seal against the inner
surface 16' of wall 16 of cup 10.
[0026] It should be noted that the height from the lowermost corner
26 of wall 24 to the upper curvilinear portion 22 of channel 18 is
arranged, in combination with the several diameters mentioned, to
provide the desired result of a leak resistant seal between cup 10
and lid 12.
[0027] Proceeding radially inwardly from the lowermost corner 26 of
wall 24, in the embodiment shown in FIGS. 2a-3, a substantially
flat, concentric reinforcing web or flange 36 extends radially
inwardly from channel 18 towards the center of lid 12 to a lower
extremity of an inwardly inclined upstanding outer wall 38 of a
central plateau region 40. As shown in FIGS. 2b and 2c, wall 38
extends from the lowermost to above the uppermost extremity of
sealing channel 18 (and rim bead 14) so that plateau region 40 is
displaced vertically above sealing channel 18. The top surface 42
of plateau region 40 may be inclined as shown in FIG. 2b. A
downwardly extending eccentric wall 44 extends from the top surface
42 to a closed center web section 46 of lid 12. Center web section
46 may be flat, concave or convex but preferably is concave as
shown. The top surface 42 of plateau region 40 is provided with a
drinking orifice 48 shown as an oval hole in the highest and widest
region of plateau region 40. As should be apparent from FIG. 2b,
this location of orifice 48 provides a maximum height and width for
the portion of plateau 40 from which liquid is emitted to the
person drinking from the cup 10. The orifice 48 may therefore be
sized appropriately for comfortable consumption of the liquid.
[0028] Taking into account the necessary height for wall 24 in
order to provide a good seal around channel 18, stiffening or
reinforcing members such as hollow domes 34 (FIGS. 2a-3) or hollow
elongated ridges or ribs 34' (FIGS. 5a-6) molded in the radially
extending flange 36, or their equivalent, are provided to prevent
deformation of the flange 36 and to maintain the required diameter
at the lowermost corner 26 (or 26') for a continuous interference
fit when the lid 12 is plug fit into cup 10.
[0029] In an alternative embodiment of the invention shown in FIGS.
5a-6, reference numbers for corresponding elements are numbered the
same as in the preceding figures but are followed by a ' (prime
symbol). The alternative arrangement also illustrates a different
set of dimensions for use in connection with a cup having a maximum
diameter at its top of 3.66 inches and a rim bead of 0.18 inches.
As can be seen by referring to FIGS. 5a-6, certain of the elements
shown in those figures are eccentrically positioned to a greater
extent than is the case in the embodiment shown in FIGS. 3a-4. One
result of such greater eccentricity is that reinforcing flange or
web 36' occupies a greater area than the area occupied by
reinforcing flange 36 in the FIG. 3a-4 embodiment. This is
particularly evident in the portion of reinforcing flange 36' which
is diametrically opposite the portion thereof between the drinking
orifice 48' and the outer edge of lid 12'.
[0030] In order to maintain a desired stiffness in flange 36' so as
to hold wall 24' of lid 12' in firm, sealing relationship against
the adjacent inner surface 16' of cup 10, the reinforcing dimple
members 34' are elongated radially to the form of ribs of
increasing length proceeding circumferentially away from drinking
orifice 48'. It should be noted that, in at least a portion of the
flange 36', where the horizontal dimension of flange 36' may be
small, the upstanding walls adjacent the flange are close to each
other and there is no need (or space) for the reinforcing dimples,
domes or ribs.
[0031] It should also be noted that the embodiment shown in FIGS.
5a-6 also includes an elongated skirt having an additional
transition member 50' which will bring the lowermost member 32' of
the skirt further outward and along the side of cup 10.
[0032] Significant advantages of a lid according to the present
invention are realized from the inside plug fit of the innermost
wall of the sealing channel and cup wall, the relatively long
single or multiple step outside skirt and the radial reinforcing
slots or dimples in the reinforcing flange which maintain the
sealing channel in contact with the cup wall. That is, the radial
slots/dimples provide added interior support for the plugged lid
surface and assist in holding the plug fit surface area of the lid
in contact with the cup wall surface. The deep inside plug fit
provides added surface area contact with which to seal the lid
surface to the cup wall surface, thus preventing leakage between
the surfaces. The outer skirt design, in conjunction with the
reinforced deep plug, allows higher rim to lid interference levels
which assist in preventing distortion on the outer portion of the
lid, while applying more pressure to the cup rim.
[0033] The desired results are a greater lid to cup rim contact
area, thus suppressing the flow of liquid between the lid and cup
rim.
[0034] In view of the foregoing description, numerous modifications
and alternative embodiments of the invention will be apparent to
those skilled in the art. Accordingly, this description is to be
construed as illustrative only and is for the purpose of teaching
those skilled in the art the best mode of carrying out the
invention. Details of the structure may be varied substantially
without departing from the spirit of the invention.
* * * * *