U.S. patent application number 11/559527 was filed with the patent office on 2007-05-31 for container.
This patent application is currently assigned to THE GLAD PRODUCTS COMPANY. Invention is credited to Ryan J. Coonce, Rebecca S. Reuhs, Edward B. Tucker.
Application Number | 20070119743 11/559527 |
Document ID | / |
Family ID | 38086381 |
Filed Date | 2007-05-31 |
United States Patent
Application |
20070119743 |
Kind Code |
A1 |
Tucker; Edward B. ; et
al. |
May 31, 2007 |
CONTAINER
Abstract
Containers having a cover and a base provide covers that may be
locked together. In addition the container covers may be locked to
a sidewall of the container base. The container cover includes a
first closure portion and a cover engagement portion. The base
includes a second closure portion and a base engagement portion.
The first closure portion of the cover is sealingly engageable with
the second closure portion of the base to define a sealed storage
area. The cover engagement portion of a cover is releaseably
lockable with the cover engagement portion of a second cover to
form a locked cover stack. The cover engagement portion of the
cover is also releaseably lockable with the base engagement portion
of the base.
Inventors: |
Tucker; Edward B.;
(Yorkville, IL) ; Coonce; Ryan J.; (Palatine,
IL) ; Reuhs; Rebecca S.; (Chicago, IL) |
Correspondence
Address: |
THE CLOROX COMPANY
P.O. BOX 24305
OAKLAND
CA
94623-1305
US
|
Assignee: |
THE GLAD PRODUCTS COMPANY
Oakland
CA
|
Family ID: |
38086381 |
Appl. No.: |
11/559527 |
Filed: |
November 14, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/US06/00263 |
Jan 4, 2006 |
|
|
|
11559527 |
Nov 14, 2006 |
|
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|
60655830 |
Feb 23, 2005 |
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Current U.S.
Class: |
206/503 |
Current CPC
Class: |
B65D 21/0223 20130101;
B65D 21/0219 20130101; B65D 21/0222 20130101; B65D 2543/00027
20130101 |
Class at
Publication: |
206/503 |
International
Class: |
B65D 21/00 20060101
B65D021/00 |
Claims
1) A container comprising: a cover comprising a first closure
portion, a cover engagement portion, the first closure portion
being sealingly engageable with a second closure portion of a base
so that when the first and second closure portions are engaged with
each other, the cover and the base define a substantially sealed
storage area, the cover engagement portion of the cover being
engageable with the cover engagement portion of a second cover; and
the base comprising an open top, a bottom, a sidewall extending
from the bottom, a base engagement portion disposed along the
sidewall and the second closure portion, the cover engagement
portion being receivingly engageable by the base engagement
portion.
2) The container of claim 1 wherein: a) the cover engagement
portion comprises an upper protrusion and a lower protrusion; b)
the second closure portion of the base includes a flange, the
flange being notched to remove a part of the flange in an area
adjacent to the base engagement portion thereby defining an upper
retaining edge; c) the base engagement portion comprising a first
sidewall and an opposing second sidewall, each sidewall comprising
a groove disposed thereon; and d) upon engagement of the cover
engagement portion with the base engagement portion, the upper
protrusion engages with the groove of the each of the first and
second sidewalls and the lower protrusion engages with the upper
retaining edge.
3) The container of claim 1, wherein the base and the cover are
made from a process selected from the group consisting of
thermoforming, blow molding, injection molding, and combinations
thereof.
4) The container of claim 1, wherein the base and the cover are
made from a material selected from the group consisting of
polystyrene, Crystalline Polyethylene Terephthalate (CPET),
Amorphous Polyethylene Terephthalate (APET), Low Density
Polyethylene (LDPE), High Density Polyethylene (HDPE), Polyvinyl
Chloride (PVC), Polycarbonate (PC), and foamed polypropylene.
5) A cover of a container, the cover comprising a first closure
portion, a cover engagement portion, the first closure portion
being sealingly engageable with a second closure portion of a base
of the container, the cover engagement portion being receivingly
engageable by a base engagement portion disposed along a sidewall
of the base.
6) The cover of claim 5, wherein the cover engagement portion of
the cover comprises: an upper protrusion, the upper protrusion
being sealingly engageable with grooves disposed on each of the
first sidewall and an opposing second sidewall of the base
engagement portion; and a lower protrusion, the lower protrusion
being engageable with an upper retaining edge of the base, the
upper retaining edge being defined by removing a part of a flange
in an area adjacent to the base engagement portion.
7) The cover of claim 6, wherein the lower protrusion of the cover
is engageable with the upper protrusion of a second cover.
8) A base of a container, the base comprising: an open top; a
bottom; a sidewall extending from the bottom; a base engagement
portion disposed along the sidewall; a second closure portion; a
flange disposed along the second closure portion; and an upper
retaining edge defined by removing a part of the flange in an area
adjacent to the base engagement portion, wherein the base
engagement portion is receivingly engageable by a cover engagement
portion of a cover of the container.
9) The base of claim 8, wherein the base engagement portion
comprises: a first sidewall and an opposing second sidewall; a
groove disposed on each of the first and second sidewalls; and a
backwall extending from the bottom, the backwall joining the first
sidewall and an opposing second sidewall.
10) The base of claim 9, wherein the groove of the each of pair of
the first and second sidewalls is engageable with an upper
protrusion of the cover engagement portion and the upper retaining
edge is engageable with a lower protrusion of the cover engagement
portion.
11) The base of claim 8, wherein the open top of the base of the
container is engageable with the open top of the base of a second
container to stack the base of the container and the second
container together.
12) A system of containers, the system comprising: a cover, the
cover comprising a cover engagement portion, the cover engagement
portion being receivingly engageable with a base engagement portion
disposed along a sidewall of a base; the base comprising an open
top, a bottom, the sidewall extending from the bottom, a second
closure portion, a flange disposed along the second closure
portion, and the base engagement portion; and a second cover, the
second cover comprising a second cover engagement portion, the
second cover engagement portion of the second cover being
engageable with the cover engagement portion of the cover.
13) The system of claim 12, wherein the cover engagement portion
comprises an upper protrusion and a lower protrusion.
14) The system of claim 13, wherein the base engagement portion
comprises: a first sidewall and an opposing second sidewall; a
groove disposed on each of the first and second sidewalls; and a
backwall extending from the bottom, the backwall joining the first
sidewall and an opposing second sidewall.
15) The system of the claim 14, wherein the base further comprises
an upper retaining edge, the upper retaining edge being defined by
removing a part of the flange in an area adjacent to a base
engagement portion.
16) The system of claim 15, wherein when the cover engagement
portion engages with the base engagement portion, the upper
protrusion engages the groove of each of the pair of the first and
second sidewalls and the lower protrusion engages the upper
retaining edge.
17) The system of claim 16, wherein the lower protrusion of the
cover is engageable with the upper protrusion of the second
cover.
18) The system of claim 17, wherein the open top of the base is
engageable with the open top of a second base to stack the base and
the second base together.
Description
[0001] This application is a continuation in part of International
Application No, PCT/US 06/06263, filed Feb. 22, 2006, which claims
benefit of U.S. Provisional Application No. 60/655,830, filed Feb.
23, 2005.
FIELD OF THE INVENTION
[0002] The present invention relates generally to containers, and,
more particularly, to containers whose covers may be locked
together and further whose covers may be locked to the bases of the
containers.
BACKGROUND OF THE INVENTION
[0003] Rigid, thermoplastic food containers are generally known.
Users often accumulate a large number of these containers in
different sizes and shapes. When not in use, the containers are
often stored haphazardly into drawers. In this case, the unused
containers take up a great deal of room, and finding a matching
base and cover in a disarranged drawer may be difficult. To avoid
this, some users stack the containers in cabinets. While the bases
of the containers usually nest and therefore take up less room than
in a disorganized drawer, it may still be difficult to match a base
with a cover. In addition, the covers may not stack and the covers
may tend to topple down. When the containers are in use to store
food, the containers are often stacked one on top of another in
cabinets or in a refrigerator. These stacks may be precarious, and
their fall may cause food to spill from the containers. Many users
would find it desirable if the containers, whether empty or in use,
could be stored in a manner space efficient, less precarious, and
more structurally rigid.
[0004] During large-scale manufacturing, the covers may be
transported in bulk before being separated out for individual
packaging. During bulk handling, manufacturers would find it
desirable if the covers would form a stack stable enough to resist
the vertical and lateral movements caused by forces typically
encountered during manufacturing operations.
[0005] The present invention has as a general aim to provide
containers that satisfy both users and manufacturers.
SUMMARY OF THE INVENTION
[0006] In view of the foregoing, the present invention provides
containers whose covers can be stacked together in different ways.
First, the covers can be stacked into an "aligned" stack. The
aligned stack provides enough structural rigidity for bulk handling
during manufacturing. Second, the covers can be stacked into a
"locked" stack. The locked stack provides even more structural
rigidity than does the aligned stack and is useful when storing
unused covers. Another embodiment of the invention is a container
with a cover engaged to the sidewall of a base. The cover can be
engaged to its corresponding base. The engaged structure is firm
enough to keep the cover and the base together while storing the
unused container. In other embodiment of the invention, multiple
covers can be engaged to a stack of multiple bases. The system of
multiple covers and bases is rigid enough to keep the system intact
and organized during storage of unused containers.
[0007] In some embodiments, the container cover includes a first
closure portion, an engagement portion, and an alignment portion.
The base includes a second closure portion. The first closure
portion of the cover is sealingly engageable with the second
closure portion of the base to define a substantially sealed,
leak-proof, and re-sealable storage area for items such as food.
The alignment portion of the cover is engageable with the alignment
portion of a second cover to form an aligned cover stack. The
engagement portion of the cover is engageable with the engagement
portion of a second cover to form a locked cover stack. In other
embodiments of the invention, the base includes a base engagement
portion. The engagement portion of the cover is engageable with the
base engagement portion of the base, to keep the cover attached to
the sidewall of the base. When the engagement portion of the cover
engages with the engagement portion of the second cover, the cover
and the second cover are firmly attached to the sidewall of the
base or a stack of multiple bases.
[0008] The covers and bases can be economically constructed from
relatively thin-gauge plastic so that the user can either wash them
after use or dispose of them with the view that their purchase
price allows them to be used as a consumable good. The container
can be readily manufactured, for example, with conventional
thermoforming equipment. The cover can be made from a
semi-transparent material to ensure satisfactory visibility of the
container's contents. The container can be suitable for
refrigerator, freezer, microwave, and machine dishwasher use.
[0009] The features of the present invention will become apparent
to one of ordinary skill in the art upon reading the detailed
description, in conjunction with the accompanying drawings,
provided herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is an isometric view of a container with a cover and
a base according to an embodiment of the present invention;
[0011] FIG. 2 is an isometric view of the container cover of FIG.
1;
[0012] FIG. 3 is a top plan view of the container cover of FIG.
1;
[0013] FIG. 4 is an isometric view of the container base of FIG.
1;
[0014] FIG. 5 is a top plan view of the container base of FIG.
1;
[0015] FIG. 6 is a side sectional view of the container of FIG.
1;
[0016] FIG. 7 is an enlarged, detail view of a portion of FIG.
6;
[0017] FIG. 8 is side sectional view of another embodiment of the
container shown in FIG. 7;
[0018] FIG. 9 is a side sectional view of another embodiment of the
container shown in FIG. 7;
[0019] FIG. 10 is a side sectional view of a stack of two sealed
containers;
[0020] FIG. 11 is a side sectional view of a stack of two nested
container bases with two locked container covers;
[0021] FIG. 12 is a side sectional view of another embodiment of
the stack of FIG. 11;
[0022] FIG. 13 is a side sectional view of a stack of two nested
container bases with one locked container cover and with one
aligned cover;
[0023] FIG. 14 is a side sectional view of another embodiment of
the stack of FIG. 13;
[0024] FIG. 15 is a side sectional view of an aligned stack of a
container cover and a base;
[0025] FIG. 16 is a side sectional view of a stack of two nested
container bases with two aligned container covers;
[0026] FIG. 17 is a side sectional view of a stack of two nested
container bases with one aligned container cover and with one
locked container cover;
[0027] FIG. 18 is a side sectional view of a locked stack of two
container covers;
[0028] FIG. 19 is an enlarged, detail view of a portion of FIG.
18;
[0029] FIG. 20 is a side sectional view of an aligned stack of two
container covers;
[0030] FIG. 21 is an enlarged, detail view of a portion of FIG.
20;
[0031] FIG. 22 is an isometric view of the base of another
embodiment of the container of FIG. 1;
[0032] FIG. 23 is an enlarged, detailed isometric sectional view of
the base of FIG. 22;
[0033] FIG. 24 is an enlarged, detailed plane sectional view of the
base of FIG. 22 along section line 23-23';
[0034] FIG. 25 is an isometric view of an embodiment of the present
invention;
[0035] FIG. 26 is an enlarged sectional view of the embodiment of
FIG. 25 along axis 26-26';
[0036] FIG. 27 is an isometric cross-sectional view of the
embodiment of FIG. 25;
[0037] FIG. 28 is another embodiment of the present invention;
and
[0038] FIG. 29 is another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0039] Turning to the drawings, wherein like reference numerals
refer to like elements, a first embodiment of the present invention
is illustrated in FIGS. 1 through 5. A container 100 includes a
flexible cover 102 sealingly engaged to a base 104. In the example
of FIGS. 1 through 5, the container 100 is depicted as
substantially square with rounded corners. In other embodiments of
the present invention, the container 100 has other shapes such as
rectangular, circular, or elliptical.
[0040] The container cover 102 can include at least one gripping
tab 106 to facilitate removal of the cover 102 from the container
base 104. In some embodiments, the gripping tab 106 includes one or
more cross-ribs or a textured surface to improve a user's grip on
the tab 106.
[0041] The container cover 102 illustrated in FIGS. 2 and 3
includes an engagement portion 200 that allows the cover 102 to
engage with the engagement portion 200 of a second cover 102 to
form a locked stack of covers 102. This locking feature makes the
resultant stack of covers more structurally rigid and thus less
precarious than a traditional, non-interlocked, stack of
covers.
[0042] The engagement portion 200 of FIGS. 2 and 3 is depicted as
circular but, as with the shape of the container 100 itself, other
shapes are possible. In some embodiments, a standard shape and
configuration of the engagement portion 200 is used with covers 102
of various shapes and sizes. This enhances storage flexibility by
allowing different types of covers 102 to be stored together in a
locked stack. The engagement portion 200 can also be chosen to have
a shape or otherwise include elements that provide an aligned or
locked stack of covers 102 with rotational alignment where rotation
is defined about an axis normal to the point 302 at which midlines
304 and 306 of the cover 102 intersect as shown in FIG. 3. For
instance, shapes that inherently require alignment prior to
engagement or that may be self-aligning during the process of
connecting engagement portions would be shapes with linear or
curvilinear sides, vertices or lobes such as triangular, square,
rectangular, or multi-petal shapes. Additionally, the cover may
have one or more elements on or about the engagement portion that
require alignment prior to connection of engagement portions or
elements that may be self-aligning during the process of connecting
engagement portions.
[0043] The container cover 102 may have a central field 300, shown
in FIG. 3 on the top of the engagement portion 200. The central
field 300 may include an embossed symbol such as a manufacturer's
mark or may allow a user to attach a label or to write information,
such as the date or user's name. When the central field 300
includes a writeable area, that area could be of an opaque color
which would receive a contrasting color from a writing instrument.
The writeable area could be incorporated into the material for the
container cover 102 or could be applied to that material by
printing.
[0044] The container cover 102 of FIGS. 1 through 3 can be
constructed with a wall thickness thinner than that of a container
base 104. The cover 102 can be made from any suitable plastic and
can be made by any suitable technique, such as thermoforming. In
one embodiment, the cover 102 can be formed from polypropylene. Due
to the thermoforming process, the wall thickness of the cover 102
can vary. A thinner container cover 102 reduces material costs and
increases flexibility to more easily accommodate its removal from,
and engagement with, a container base 104. The cover 102 can
maintain adequate flexibility for proper sealing even during
typical freezer temperatures.
[0045] The container base 104 of FIGS. 4 and 5 includes a bottom
400 and a sidewall 402 extending from the periphery of the bottom
400. The bottom 400 includes a raised lower section 404 to
accommodate the engagement portion 200 of a container cover 102
when containers 100 are stacked together. This feature is further
discussed and illustrated below. Just as the engagement portion 200
of FIG. 3 can include a central field 300, a similar field for a
manufacturer's mark or for user information could be included in
the raised portion 404 of the base 104.
[0046] The container base 104 of FIGS. 1, 4, and 5 can be made from
any suitable plastic with sufficient thickness to withstand without
deforming the heat of microwave cooking and of top-shelf
dishwashing. It should also remain sturdy during lifting while
laden with hot food. The base 104 can be made from any suitable
plastic and can be made by any suitable technique, such as
co-extrusion, lamination, injection molding, blow-molding,
thermoforming, or overmolding. In one embodiment, the container
base 104 is formed from polypropylene. The wall thickness of the
container base 104 can vary due to the manufacturing process.
[0047] FIGS. 6 through 9 present embodiments of a container 100
whose cover 102 is sealingly engaged with its base 104. FIG. 6
shows the cover 102 cooperating with the base 104 to define a
sealed storage compartment 600. The cover 102 can be sufficiently
flexible to allow a user to create a vacuum in the container 100
upon sealing. In order to create a vacuum, the user could, for
example, depress the cover 102 during the closing of the container
100. A return force imparted upon the cover 102 by the resiliency
of the material of the cover 102 will urge the cover 102 to return
to its normal position, thereby creating a vacuum. To facilitate
convenient sealing engagement of the cover 102 with its base 104,
the users can, at their discretion, apply downward force to only
the engagement portion 200 of the container cover 102. The
engagement portion 200 is located to accept and distribute the
force to the first closure portion 700 of the cover 102 during
sealing to the base 104. The engagement portion 200 may also act as
a convenient handle for grasping the cover 102.
[0048] In the embodiments of FIGS. 6 through 9, the container 100
uses a locking rim design that includes both inside and outside
seals as will be described. The present invention can be embodied
with a variety of closure designs including outer closures and/or
inner closures.
[0049] FIG. 7 depicts an embodiment of the closure portions used to
engage the cover 102 with the base 104 of the container 100. The
cover 102 includes a first closure portion 700 in the form of a
raised locking ring. The first closure portion 700 of the cover 102
can be engaged with a second closure portion 702 of the base 104 to
provide a leak-resistant, re-sealable closure.
[0050] The first closure portion 700 includes an inner wall 704, a
retention bead 706, and an outer wall 708. The inner wall 704, the
retention bead 706, and the outer wall 708 define a first sealing
surface, which is part of the lower surface of the cover 102. The
first closure portion 700 can include one or more locking ridges
710. The outer wall 708 extends between the retention bead 706 and
a flange 712. The flange 712 can provide a convenient gripping
surface to facilitate the removal of the cover 102 from the base
104.
[0051] As illustrated in FIG. 7, the second closure portion 702 of
the base 104 is a raised locking ring that extends from an upper
edge of the sidewall of the base 104. The second closure portion
702 includes an inner wall 714, a retention bead 716, and an outer
wall 718. The inner wall 714, the retention bead 716, and the outer
wall 718 define a second sealing surface, which is part of the
upper surface of the base 104. The second closure portion 702 can
include one or more locking ridges 720. The outer wall 718 extends
between the retention bead 716 and a flange 722. The flange 722 can
provide a convenient gripping surface to facilitate the removal of
the cover 102 from the base 104.
[0052] The first and second closure portions 700 and 702 can be
configured to be slightly different in size to form an interference
fit therebetween. The interference fit between the first and second
closure portions 700 and 702 can provide a sealing engagement
between the closure portions. As a result, when the two pieces are
engaged, a positive seal can be formed between the first and second
sealing surfaces around the perimeters of the base 104 and of the
cover 102.
[0053] The engagement of the first and second closure portions 700
and 702 can be accompanied by an audible "snap" indicating that the
container is securely closed.
[0054] In the example of FIG. 7, the inner wall 704 of the first
closure portion 700 of the cover 102 extends to the engagement
portion 200. This engagement portion 200 includes an upper
protrusion 724 and a lower protrusion 726.
[0055] In the embodiment of FIG. 7, the cover 102 includes a ridge
728 on the outer wall 708 of the first closure portion 700. FIG. 8
presents another embodiment without this ridge. In general, the
first and second closure portions 700 and 702 and the engagement
portion 200 shown in FIGS. 6 through 9 are examples only, and many
other types of closure and engagement portions could be used with
the present invention. For example, the engagement portion 200
could include complementary locking rings. As these and many other
types of closure and engagement portions are well known in the art,
they need not be discussed at length here.
[0056] FIG. 9 shows another embodiment of the cover. The cover 102
of FIG. 9 includes an alignment ridge 900 located on the outer wall
708 of the first closure portion 700. This alignment ridge 900 is
discussed in detail below.
[0057] In FIG. 10, the sealed container 100 rests on top of a
second sealed container 1000. The raised lower section 404 of the
base 104 of the upper container 100 accommodates the engagement
portion 200 of the cover 1002 of the lower container 1000.
[0058] FIGS. 11 and 12 show the utility of an embodiment of the
invention when the containers are in storage. In the Figures, a
stack of two nested container bases 104 and 1100 is joined to a
locked stack of covers 102 and 1102. The lower cover 102 is
sealingly engaged with the upper base 104 to form a structurally
rigid stack.
[0059] In the embodiment of FIGS. 11 and 12, the two covers 102 and
1102 are locked together by their engagement portions 200. As
described in relation to FIG. 7, the engagement portions 200 can
each include an upper protrusion 724 and a lower protrusion 726.
Each protrusion 724, 726 is convex on one side and concave on the
other. The lower protrusion 726 of the upper cover 1102 fits over
and receives the upper protrusion 724 of the lower cover 102, thus
locking the covers 102 and 1102 together. In this manner, the
covers 102 and 1102 are held together and form a structurally
stable cover stack. Other embodiments of the engagement portion may
include one or more of the following features to enable engagement:
convex portions or ribs, concave portions or ribs, linear or
curvilinear undercuts, discrete snap elements or buttons,
interference fits, textured surfaces, or elements that modify
surface friction or tackiness at or around the point of engagement.
The engaging areas that create a locking condition can be
continuous about the engagement portion or discretely segmented
about the engagement portion. In some embodiments, the force
required to connect the covers may differ substantially from the
force required to disengage the covers. For instance, it may be
beneficial during manufacturing that the force needed to connect
the covers is less than the force required to separate the covers.
As a result, the covers are relatively easy to connect during
manufacturing, yet they will lock securely and not undesirably
separate during the manufacturing process. To accomplish this, the
protrusions on the engagement portion may be designed where, for a
given protrusion, the upper protrusion edge comprises a gradual
taper whereas the lower protrusion edge comprises a more abrupt
shape. For example, in one embodiment, the shape of the protrusion
may be similar to a barbed hook with gradual taper on the upper
edge of the barb that would impart little resistance during
engagement and with an abrupt shape on the lower edge of the barb
that would impart relatively high resistance during disengagement.
Conversely, it may be beneficial to design the engagement portion
so that the force that needs to be applied to connect the covers is
more than the force required to separate the covers, since the user
may perceive that a high connecting force equates to satisfactory
locking integrity, whereas a weak connecting force may lead the
user to perceive that the cover stack lacks the integrity required
to insure the expected organizational benefit. Thus the high
connecting force provides the perceived benefit, yet a lower
disengagement force does not require that the user untowardly
struggle during separation of covers. To accomplish this, the
protrusions on the engagement portion may be designed where, for a
given protrusion, the upper protrusion edge comprises an abrupt
shape whereas the lower protrusion edge comprises a more gradual
taper. For example, in one embodiment, the shape of the protrusion
may be a reversed barb with an abrupt shape on the upper edge of
the barb that would impart relatively high resistance during
engagement and with a gradual taper on the lower edge of the barb
that would impart little resistance during disengagement.
Furthermore, during the process where the user applies force to
aligned covers in a direction normal to the general cover plane so
as to lock the covers together, the engagement portion can provide
tactile or audible feedback upon locking. In this way the user
would sense that the covers are connected and that no further force
need be applied.
[0060] The container bases 104 and 1100 are shown nested in FIGS.
11 and 12 but are not locked together. In many applications,
nesting the container bases without locking them together provides
sufficient structural rigidity to a stack of bases. It is possible,
however, to apply the techniques of the present invention to the
bases themselves and to thus provide a mechanism for locking the
bases together. The same types of closure and engagement portions
available for locking the covers together or for locking the covers
to the bases can be adapted to locking the bases together.
[0061] The container covers 102 and 1102 of FIG. 11 include the
ridge 728 described in relation to FIG. 7, while the covers in FIG.
12 do not include this feature. The ridge 728 provides a
rigidifying function to the outer wall 708 and also provides a
retaining ledge to assist de-nesting of covers during
manufacture.
[0062] FIGS. 13 and 14 present another position for the stack of
covers in FIGS. 11 and 12. The container bases 104 and 1100 are
nested together and the lower cover 102 is locked onto the upper
base 104. However, the upper cover 1102 is not locked to the lower
cover 102. Instead, the upper cover 1102 is resting on, and aligned
with, the lower cover 102. In this configuration, the two covers
102 and 1102 are said to form an "aligned" stack to distinguish it
from the locked stack of FIGS. 11 and 12. The ability to form an
aligned, but not locked, stack is important in manufacturing
because it allows the covers to be transported in bulk before being
separated out for individual packaging. The aligned stack is stable
enough to resist the vertical, lateral, or rotational movements
caused by forces typically encountered during manufacturing
operations, but the covers are not so strongly connected that they
hinder de-nesting when necessary.
[0063] The tab 106 (see FIG. 1) can be designed so that the tabs
nest in an interdigitating fashion when in a stack of covers so
that the covers are kept in an aligned configuration. In one
embodiment, the design of the tab 106 permits stable cover-to-cover
stacking in the immediate vicinity of the tab 106 in the locked
state, such that a portion of the tab 106 comes to rest on a
portion of the cover below it in the stack to provide resistance to
further stack compression.
[0064] In the embodiment of FIG. 13, the covers 102 and 1102 align
by touching in two areas. First, the engagement portions 200 of the
covers 102 and 1102 each includes a lower shoulder 1300 and an
upper shoulder 1302. The lower shoulder 1300 of the upper cover
1102 rests on the upper shoulder 1302 of the lower cover 102.
Second, the flange 712 of the upper cover 1102 rests on the outer
wall 708 of the lower cover 102. These two contact areas serve to
align the covers 102 and 1102 into a stack less structurally rigid
than a locked stack, but sufficiently rigid for many purposes.
Comparing FIGS. 11 and 13 shows how an aligned stack can be
converted into a locked and rotationally aligned stack by an
application of pressure upon the stacked items. FIG. 11 shows that
when force is applied to the aligned stack of FIG. 13 to create a
locked stack, the flange 712 of the upper cover 1102 is pushed
farther down the outer wall 708 of the lower cover 102. Cover
alignment is further rigidified by the touching of covers 102 and
1102 at the inside wall of the closure portions. In the embodiment
of FIG. 11, the cover inner wall 704 includes an upper shoulder
1104 located just above the uppermost locking ridge 710 and a lower
shoulder 1106 located just below the lowermost locking ridge 710.
Thus, in this pair of locked covers, the lower shoulder 1106 of the
cover 1102 rests on the upper shoulder 1104 of the cover 102.
Considering both FIGS. 11 and 13, the flange 712 that creates an
aligned condition can be continuous along the perimetric path of
the first closure portion 700 or discreetly segmented along the
perimetric path of the first closure portion 700. Considering FIG.
12, the contacting shoulders 1104 and 1106 of the inside wall 704
that create an aligned condition between locked covers can be
continuous along the perimetric path of the first closure portion
700 or discreetly segmented along the perimetric path of the first
closure portion 700. In some embodiments, this alignment feature
may be desirable to ensure that the connected covers are aligned
rotationally about an axis normal to the center of the covers,
especially when the covers include engagement portions that permit
rotation between the covers. In some embodiments, if the alignment
feature were absent, then the covers would be free to rotate. Free
rotation could have undesirable consequences because the cover
stack may be inadequately organized to facilitate manufacturing or
may inadequately provide an organizational benefit to the user.
[0065] The embodiment of FIG. 14 differs from that of FIG. 13 in
that the flange 712 of the upper cover 1102 does not come down far
enough to touch the lower cover 102 when the covers 102 and 1102
are in an aligned stack. Variations such as those between the
embodiments of FIGS. 13 and 14 can be chosen to alter the amount of
rigidity present in an aligned stack. Even though the flange 712 of
the upper cover 1102 does not come down far enough to touch the
lower cover 102 in this less rigid aligned stack, the contact
between the lower shoulder 1300 of the engagement portion 200 of
the upper cover 1102 and the upper shoulder 1302 of the lower cover
102 can provide concentric or rotational alignment to assist the
user in aligning the engagement portions 200 during the process of
connecting covers. Comparing FIGS. 12 and 14 shows how an aligned
stack can be converted into a locked and rotationally aligned stack
by an application of pressure upon the stacked items. FIG. 12 shows
that when force is applied to the aligned stack of FIG. 14 to
create a locked stack, the cover alignment is further rigidified by
the touching of covers 102 and 1102 in two areas. First, the flange
712 of the upper cover 1102 rests on the outer wall 708 of the
lower cover 102. Second, the lower shoulder 1106 of the upper cover
1102 rests on the upper shoulder 1104 of the lower cover 102. In
some embodiments, this alignment feature may be desirable to ensure
that the connected covers are aligned rotationally about an axis
normal to the center of the covers, especially when the covers may
include engagement portions that permit rotation between the
covers.
[0066] FIG. 15 shows that containers cover 102 can be aligned,
without locking, onto the top of a container base 104. FIG. 16
shows an aligned stack of two covers 102 and 1102 on top of a
nested stack of bases 104 and 1100. FIG. 17 differs from FIG. 16 in
that the upper cover 1102 is locked onto the lower cover 102.
Comparing FIGS. 16 and 17 shows how an aligned stack can be
converted into a locked stack by an application of pressure upon
the stacked items.
[0067] FIG. 16 also shows another embodiment of the alignment
portion of the container covers 102 and 1102. An alignment ridge
900 is located on the outer wall 708 of the covers 102 and 1102.
When in an aligned stack, the flange 712 of the upper cover 1102
rests on the alignment ridge 900 of the lower cover 102 increasing
the rigidity of the stack. FIG. 17 shows that when pressure is
applied to the aligned stack to create a locked stack, the flange
712 of the upper cover 1102 is pushed past the alignment ridge 900
of the lower cover 102.
[0068] FIGS. 18 and 19 emphasize the compactness of a locked stack
of container covers 102 and 1102, while FIGS. 20 and 21 emphasize
the compactness of an aligned stack of container covers. While the
aligned stack is not quite as compact as the locked stack, the
compactness of either stack is a significant benefit of the present
invention when covers are stored for future use.
[0069] FIG. 22 shows another embodiment of the container 100 of
FIG. 1. As mentioned above, the container 100 has the cover 102 and
the base 104. As mentioned earlier, the base 104 and the cover 102
are made from a process selected from the group consisting of
thermoforming, blow molding, injection molding, and combinations
thereof. As shown in FIG. 22, the base 104 of the container 100
includes a base engagement portion 2200 and an upper retaining edge
2210. The base engagement portion 2200 comprises a first sidewall
2220a and a second opposing sidewall 2220b. The flange 722 (see
also FIG. 7) is notched to remove a part of the flange 722 in an
area adjacently above the base engagement portion 2200 thereby
defining the upper retaining edge 2210. As best seen in FIG. 26,
the base engagement portion 2200 is receivingly engageable with the
upper protrusion 724 of the cover engagement portion 200 of the
cover 102. The upper retaining edge 2210 is engageable with the
lower protrusion 726 of the cover engagement portion 200 of the
cover 102. FIG. 22 shows another base engagement portion disposed
on the sidewall 402. In another embodiment of the present
invention, four base engagement portions may be present on the
sidewall 402 of the base 104. The base 104 shown in FIG. 22 also
comprises an open top 2230.
[0070] FIG. 23 illustrates the base engagement portion 2200 in a
more detailed manner. FIG. 23 illustrates an isometric sectional
view of the base 104 shown in FIG. 22 along section line 23'-23',
in accordance with an embodiment of invention. The base engagement
portion 2200 comprises a backwall 2300, a first sidewall 2220a and
a second opposing sidewall 2220b. The backwall 2300 extends from
the bottom 400 of the tub 104 and joins the first sidewall 2220a
and the second opposing sidewall 2220b. The first sidewall 2220a
and the second opposing sidewall 2220b each include a groove 2310a
and 2310b, respectively. In the present embodiment of the
invention, the grooves 2310a and 2310b are concave surfaces and
disposed parallel to a vertical axis V normal to the plane of
bottom 400, as shown in FIG. 23. The grooves 2310a and 2310b are
flexible and elastic enough to engage with a convex protrusion
portion of similar size and curvature, present on the cover
engagement portion 200 of the cover 102. In an embodiment of the
present invention, the grooves 2310a and 2310b are engageable with
the upper protrusion 724 of the cover engagement portion 200 of the
cover 102. When the cover engagement portion 200 is engaged with
the base engagement portion 2200 of the base 104, the grooves 2310a
and 2310b are engaged with the upper protrusion 724 of the cover
engagement portion 200, and the upper retaining edge 2210 is
engaged with the lower protrusion 726. In other embodiments of the
present invention, the first sidewall 2220a and the second opposing
sidewall 2220b can have one or more grooves of same or different
kinds, which are engageable with their corresponding upper
protrusions present on the cover engagement portion of the cover.
In yet another embodiment, grooves 2310a and 2310b need not be
continuous along the entire length of first sidewall 2220a and the
second opposing sidewall 2220b, respectively, but rather may be
formed as one or more discrete sections. In the present embodiment
of the invention, the shape of the base engagement portion 2200 has
a rectangular wedge shape. However, in other embodiments of the
present invention, any other shape of the base engagement portion
is possible. In the present embodiment of the invention, the first
sidewall 2220a and the second opposing sidewall 2220b are shown
parallel and opposite. However, in other embodiments of the present
invention, curved and non-parallel sidewalls are also possible.
[0071] FIG. 24 illustrates an enlarged plane sectional view along
the vertical axis V, shown in FIG. 22, of the base engagement
portion 2200, in accordance with an embodiment of the present
invention. In this embodiment of the present invention, the upper
retaining edge 2210 comprises a convex peripheral edge 2400. The
convex peripheral edge 2400 is engageable with the lower protrusion
726 of the cover 102. In other embodiments of the present
invention, other mechanisms for engaging between an upper retaining
edge of a base and a cover engagement portion of a cover are
possible. For example, the upper retaining edge may comprise a
detent groove and the cover engagement portion may comprise a rib,
the rib being engageable with the detent groove. In other
embodiments of the present invention, the strength of snap fit
between the upper retaining edge and the cover engagement portion
can be improved by providing an undercut with protrusions on the
upper retaining edge and a lower protrusion on the cover engagement
portion. In one embodiment, backwall 2300 need not protrude into
base 104 to the extent depicted in FIG. 24. Backwall 2300 need only
extend just past grooves 2310a & 2310b, allowing for adequate
space for cover 102 to travel and lock within grooves 2310a &
2310b. Further, Grooves 2310a and 2310b need not be linear. They
may be shaped in concave patterns to allow for positive placement
and fit of covers 102 when engaged
[0072] FIG. 25 illustrates one embodiment of the present invention,
in which the cover 102 is engaged with the base 104 on the sidewall
402. In this embodiment of the invention, the cover engagement
potion 200 (see also FIG. 7) is receivingly engaged with the base
engagement portion 2200 of the base 104. Base engagement portion
2200 may be developed to accommodate a variety of cover engagement
portions either by shape, size or groove patterns. Engagement
between base and cover may be snap fit or friction fit. Lids may be
rotationally aligned if upper lid engagement protrusion is shaped
other than circular. The embodiment of the present invention shown
in FIG. 25 is helpful in organizing the base 104 and the cover 102
of the container 100, when the cover 102 is not sealingly
engageable with the base 104 to define a sealed storage volume. The
embodiment of invention shown in FIG. 25 is also helpful in
reducing the effort of a user to search for the cover 102 of the
base 104 in a storage area, as the cover 102 can be engaged with
the base 104. Another application of the present embodiment may be
to avoid the intermixing and misplacing of the different covers and
bases of different containers, as the covers are engageable to
corresponding bases. The transportation and storage of containers
with the covers engaged with a sidewall of the corresponding bases
is organized. A snap fit between the cover and the base is firm
enough to keep the system rigid, and the cover is releaseably
lockable and may be removed from sidewall of the base by applying
force when required.
[0073] FIG. 26 illustrates a plane sectional view of the FIG. 25
along axis 26-26', in accordance with an embodiment of the present
invention. The cover engagement portion 200 and the base engagement
portion 2300 are engaged with each other. In an embodiment of the
present invention, the upper protrusion 724 is engaged with the
grooves 2310a and 2310b of the base engagement portion 2200 and the
lower protrusion 726 of the cover engagement portion 200 engages
with the convex peripheral edge 2300 of the base 104. The engaging
feature of the cover 102 and the base 104 is firm enough to keep
the cover 102 engaged in a vertical position on the sidewall 402 of
the base 104. The convex peripheral edge 2400 of the upper
protrusion 724 is about the same size of the grooves 2310a and
2310b. When the cover 102 and the base 104 are engaged together,
the convex surface of the upper protrusion 724 and the concave
surface of the grooves 2310a and 2310b may be snap-fitted due to
the flexible and elastic nature of the cover 104. In other
embodiments of the present invention, there may be more than one
upper protrusion on the cover engagement portion with corresponding
number of grooves on the base engagement portion. In yet other
embodiments of the invention, the cover engagement portion can
comprise a groove in place of the upper protrusion and a
corresponding convex protrusion on the base engagement portion. In
other embodiments of the present invention, the cover can be
attached at an angle to the sidewall of the base.
[0074] FIG. 27 illustrates an isometric sectional view of the
embodiment of present invention shown in FIG. 25. The cover
engagement portion 200 is engaged with the base engagement portion
2200 of the base 104. In present embodiment of the invention, the
upper protrusion 724 of the cover engagement portion 200 is engaged
with the grooves 2310a and 2310b of the base engagement portion
2200. The upper protrusion 724 of the cover engagement portion 200
is a convex surface of same size and curvature as that of the
grooves 2310a and 2310b. In other embodiments of the invention,
there can be one or more grooves on the base engagement portion of
the base and corresponding number of upper protrusions on the cover
engagement portion of the cover. The flexible and elastic material
of the cover 102 and the base 104 provides a snap fit between the
upper protrusion 724 and the grooves 2310a and 2310b. The cover 102
is releaseably lockable and can be removed by applying force. In
the embodiment shown in FIG. 25, the base engagement portion 2200
has a rectangular wedge shape, but in other embodiments of the
present invention, other shapes are possible.
[0075] FIG. 28 illustrates another embodiment of the present
invention. The embodiment of the present invention shown in FIG. 28
comprises the cover 102, a second cover 2800 and the base 104. In
an embodiment of the present invention, the cover 104 comprises the
cover engagement portion 200. The cover engagement portion 200
comprises the upper protrusion 724 and the lower protrusion 726.
The second cover 2800 comprises a second cover engagement portion
2810. The second cover engagement portion 2810 of the second cover
2800 comprises a second upper protrusion 2820 and a second lower
protrusion 2830. The base engagement portion 2200 of the base 104
comprises grooves 2310a and 2310b. When the cover 102 is engaged
with the base 104, the upper protrusion 724 engages with the
grooves 2310a and 2310b, and the lower protrusion 726 engages with
the upper retaining edge 2210 of the base 104. FIG. 28 shows the
second cover 2800 being engaged with the cover 102, wherein the
second upper protrusion 2820 of the second cover 2800 is engaged to
the lower protrusion 726 of the cover 102. In other embodiments of
the present invention, additional covers can be engaged to the
embodiment shown in FIG. 28 with an upper protrusion of a third
cover engaging to the second lower protrusion 2830 of the second
cover 2800 and so on for yet additional covers. In another
application of the present invention, multiple covers engaged with
a base will be helpful in organizing a set of similar containers.
In other embodiments of the present invention, a set of containers
having different sizes of covers and bases, but having cover
engagement portions of the covers of a standard size, may engage to
a single base. This may help save both time and space for
organizing containers.
[0076] FIG. 29 illustrates another aspect of the present invention.
The embodiment of the present invention shown in FIG. 29 comprises
the base 104 a second base 2900, the cover 102 and the second cover
2800. In other embodiments of the present invention, multiple bases
of similar shape and size can be stacked together to form a stack
of bases as described in FIG. 11. In the present embodiment of the
invention, the open top 2230 (FIG. 22) of the base 104 is engaged
with a second open top 2910 of the second base 2900. The cover 102
and the second base 2800 are stacked together to help in organizing
containers 100 in a space saving manner. The cover 102 and the
second cover 2800 are engageable with each other as shown in FIG.
11. In present embodiments of the invention, the cover 102, the
second cover 2800, the base 104 and the second base 2900 are
arranged in an organized and space saving manner. In other
embodiments of present invention, one or more covers and bases of
similar containers can be stacked together and a system of multiple
covers engaged to a stack of multiple bases is possible. The
present embodiment of the invention saves the effort of a user
searching for covers and bases of containers and saves the space
for storage of containers. In other embodiments of the present
invention, during packaging of the multiple containers, the covers
are first stacked together and then the bases stacked together, the
stack of covers and stack of bases being snapped together. This
allows efficient packing of the containers thus reducing the
requirement of packaging material.
[0077] In various embodiments of the present invention, a container
comprises a base and a cover, wherein the engaging feature of the
cover to a sidewall of the base helps in arranging the container in
an organized and ordered manner. Further, in the case of multiple
covers and bases, traditional random storage and misplacement of
covers and bases can be avoided by engaging the covers to the
respective bases. During transportation of the containers, the
stack of the covers and stack of bases can be further engaged
together to save packaging material and space requirement during
transportation.
[0078] The container can be reusable, but it can also be
constructed cheaply enough that consumers see it as a disposable
item, with replacement covers and bases available separately for
retail sale. The base and the cover can be fabricated by
thermoforming a clarified polypropylene homopolymer material. In
another embodiment, the container may be fabricated by
thermoforming a clarified random copolymer polypropylene material.
Other plastic materials which would be suitable for fabricating the
container by thermoforming include PS (polystyrene), CPET
(crystalline polyethylene terephthalate), LDP (low-density
Polythenes), APET (amorphous polyethylene terephthalate), HDPE
(high density polyethylene), PVC (polyvinyl chloride), PC
(polycarbonate), and foamed polypropylene. The material used can be
generally transparent to allow a user to view the contents of the
container.
[0079] The container may include a visual indication of closure
between the container cover and the container base. The visual
indication may be a color change in the area where the cover
engages the base. In one embodiment, the closure portion on the
cover may be a first color and the closure portion on the base may
be a second color. When the closure portions are engaged, the first
and second colors produce a third color which is visible to the
user to indicate that the container is sealed.
[0080] The container may include a rough exterior surface to reduce
slipping and to improve grasping by the user, especially if the
user's hands are wet or greasy.
[0081] The container may include a self-venting feature. The
pressure in the sealed container may increase when the sealed
container and contents are heated in a microwave oven. Thus, the
container cover may include a self-venting mechanism which opens
when the pressure in the container exceeds a predetermined
value.
[0082] The container may be divided to separate foods in the
container. A divider may be integral with the container or may be a
separate component. Either the base only may include a divider or
both the base and the cover may each include a divider. The divider
located in the cover may only partially engage the divider in the
base so as to provide splash protection, or it may fully engage the
divider in the base to provide varying degrees of
inter-compartmental leak resistance.
[0083] The container may include a strip indicating the temperature
of the container and its contents.
[0084] The gripping tab can include a relieved portion that
provides less interference contact with the base during the removal
or engagement of the cover while still providing an adequate
closure portion to maintain proper sealing of the container. The
relieved portions of the gripping tab permit venting by allowing a
portion of the cover to be unsealed from the base while still
maintaining a seal around the remaining perimeter of the container.
This feature is useful in microwave cooking where the cover
prevents food from splattering onto the inside surface of the
microwave while still allowing the container to vent. By using the
gripping tab, less force is required to remove the cover from the
base. This lower opening force also reduces the possibility of
container failure from stress and fatigue. The lower opening force
can improve the ability of the user to maintain control over the
container components while removing the cover from the base and
thus to reduce the possibility of spilling the contents stored in
the container.
[0085] The use of the terms "a," "an," "the," and similar referents
in the context of describing the invention (especially in the
context of the following claims) are to be construed to cover both
the singular and the plural, unless otherwise indicated herein or
clearly contradicted by context. Recitation of ranges of values
herein are merely intended to serve as a shorthand method of
referring individually to each separate value falling within the
range, unless otherwise indicated herein, and each separate value
is incorporated into the specification as if it were individually
recited herein. All methods described herein can be performed in
any suitable order unless otherwise indicated herein or otherwise
clearly contradicted by context. The use of any and all examples,
or exemplary language (e.g., "such as") provided herein, is
intended merely to better illuminate the invention and does not
pose a limitation on the scope of the invention unless otherwise
indicated.
[0086] While the invention is described herein in connection with
certain preferred embodiments, there is no intent to limit the
present invention to those embodiments. On the contrary, it is
recognized that various changes and modifications to the described
embodiments will be apparent to those skilled in the art upon
reading the foregoing description, and that such changes and
modifications may be made without departing from the spirit and
scope of the present invention. Skilled artisans may employ such
variations as appropriate, and the invention may be practiced
otherwise than as specifically described herein. Accordingly, the
intent is to cover all alternatives, modifications, and equivalents
included within the spirit and scope of the invention. Moreover,
any combination of the above described elements in all possible
variations thereof is encompassed by the invention unless otherwise
indicated herein or otherwise clearly contradicted by context.
* * * * *