U.S. patent application number 12/958747 was filed with the patent office on 2012-06-07 for storage device having an articulated cover fitting inner and outer containers.
Invention is credited to Richard Miller, Lawrence John Racana, John E. Rusnak.
Application Number | 20120138608 12/958747 |
Document ID | / |
Family ID | 46161250 |
Filed Date | 2012-06-07 |
United States Patent
Application |
20120138608 |
Kind Code |
A1 |
Rusnak; John E. ; et
al. |
June 7, 2012 |
STORAGE DEVICE HAVING AN ARTICULATED COVER FITTING INNER AND OUTER
CONTAINERS
Abstract
A container system includes an inner container adapted to nest
inside of an outer container. A single cover sealingly engages both
the inner and outer containers. The cover includes a first closure
portion, a third closure portion, and an engagement portion. The
third closure portion may be formed from an inside surface of at
least a portion of the engagement portion. The outer container
includes a second closure portion. The first closure portion of the
cover is sealingly engageable with the second closure portion of
the outer container to define a sealed storage area. The inner
container includes a forth closure portion. The third closure
portion of the cover is sealingly engageable with the forth closure
portion of the inner container. The engagement portion of the cover
is engageable with the engagement portion of a second cover to form
a locked cover stack.
Inventors: |
Rusnak; John E.; (Aurora,
IL) ; Racana; Lawrence John; (Willowbrook, IL)
; Miller; Richard; (Worth, IL) |
Family ID: |
46161250 |
Appl. No.: |
12/958747 |
Filed: |
December 2, 2010 |
Current U.S.
Class: |
220/23.87 ;
220/254.2 |
Current CPC
Class: |
B65D 2543/00796
20130101; B65D 2543/00527 20130101; B65D 2543/00555 20130101; B65D
2543/00537 20130101; B65D 2543/00731 20130101; B65D 2543/00685
20130101; B65D 2543/00629 20130101; B65D 2543/00092 20130101; B65D
2543/00101 20130101; B65D 2543/00296 20130101; B65D 2251/08
20130101; B65D 43/0208 20130101 |
Class at
Publication: |
220/23.87 ;
220/254.2 |
International
Class: |
B65D 21/02 20060101
B65D021/02; B65D 51/20 20060101 B65D051/20 |
Claims
1. A container comprising an outer container, an inner container,
and a cover, the outer container including: a bottom; a peripheral
sidewall extending from said bottom; an open top; and a second
closure portion, the inner container fitting inside the outer
container, said inner container including: an inner container
bottom; an inner container peripheral sidewall extending from said
inner container bottom; an inner container open top; and a fourth
closure portion, the cover including: a first closure portion, said
first closure portion being sealingly engageable with said second
closure portion of said outer container such that when said first
closure portion and said second closure portion are engaged with
each other, said cover and said outer container define a first
substantially sealed storage area; and a third closure portion,
said third closure portion being sealingly engageable with said
fourth closure portion of said inner container such that when said
third closure portion and said fourth closure portion are engaged
with each other, said cover and said inner container define a
second substantially sealed storage area.
2. The container of claim 1 further comprising: an engagement
portion of said cover, said engagement portion being engageable
with a similar engagement portion of another cover; and at least
one articulation element on said cover.
3. The container of claim 2, wherein an inside surface of said
engagement portion forms at least a portion of the third closure
portion.
4. The container of claim 2 wherein said at least one articulation
element circumscribes said engagement portion of said cover.
5. The container of claim 4 wherein the bottom of said outer
container includes a raised lower section.
6. The container of claim 1 wherein said first closure portion
includes an inner wall, a retention bead, and an outer wall.
7. The container of claim 6 wherein said inner wall includes one or
more locking ridges.
8. The container of claim 7 wherein said outer wall extends between
said retention bead and a flange.
9. The container of claim 8 wherein the outer wall includes a
ridge.
10. The container of claim 1 wherein the third closure portion is
formed in a central region of said cover.
11. The container of claim 1 wherein said inner container is formed
of a gas permeable material.
12. The container of claim 1 wherein the first closure portion is
sealingly engageable with a second closure portion of said outer
container such that when said first closure portion and said second
closure portion are engaged with each other, said cover and said
outer container define a first substantially sealed storage area,
regardless of a presence or an absence of the inner container from
the container.
13. A container comprising: an inner container; an outer container;
and a cover, wherein said inner container and said outer container
are adapted to sealingly engage with said cover; and the inner
container nests within said outer container when said inner
container and said outer container are both sealingly engaged with
said cover.
14. The container of claim 13 wherein said cover comprises: a first
closure portion, said first closure portion being sealingly
engageable with a second closure portion of said outer container
such that when said first closure portion and said second closure
portion are engaged with each other, said cover and said outer
container define a first substantially sealed storage area; and a
third closure portion, said third closure portion being sealingly
engageable with a fourth closure portion of said inner container
such that when said third closure portion and said fourth closure
portion are engaged with each other, said cover and said inner
container define a second substantially sealed storage area.
15. The container of claim 14 further comprising: an engagement
portion on said cover, said engagement portion being engageable
with an engagement portion of a second cover; and at least one
articulation element on said cover, wherein an inside surface of
said engagement portion forms at least a portion of said third
closure portion.
16. The container of claim 15 wherein said at least one
articulation element circumscribes said engagement portion of said
cover.
17. The container of claim 16, wherein said third closure portion
is formed in a central region of said cover.
18. The container of claim 14, wherein said first closure portion
is sealingly engageable with said second closure portion of said
outer container independently of said third closure portion being
sealingly engaged with said fourth closure portion of said inner
container.
19. A container including an outer container, an inner container,
and a cover, the outer container comprising: a bottom; a peripheral
sidewall extending from said bottom; an open top; and a second
closure portion, the inner container, said inner container fitting
inside the outer container, said inner container comprising: an
inner container bottom; an inner container peripheral sidewall
extending from said inner container bottom; an inner container open
top; and a fourth closure portion, the cover comprising: a first
closure portion, said first closure portion being sealingly
engageable with said second closure portion of said outer container
such that when said first closure portion and said second closure
portion are engaged with each other, said cover and said outer
container define a first substantially sealed storage area; a third
closure portion, said third closure portion being sealingly
engageable with said fourth closure portion of said inner container
such that when said third closure portion and said fourth closure
portion are engaged with each other, said cover and said inner
container define a second substantially sealed storage area; an
engagement portion, said engagement portion being engageable with
an engagement portion of a second cover; and at least one
articulation element on said cover, wherein an inside surface of
said engagement portion forms at least a portion of the third
closure portion.
20. The container of claim 19, the first closure portion is
sealingly engageable with said second closure portion of said outer
container independently of said third closure portion being
sealingly engaged with said fourth closure portion of said inner
container.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to storage devices
having a cover adapted to seal an inner and an outer container.
Multiple covers of the plastic containers may be aligned together
when stacked in a first position and may be locked together in a
second position.
BACKGROUND OF THE INVENTION
[0002] 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. Related U.S. Patent Publication No.
2009/0166369, describes a system of interlocking covers for
sealable plastic containers and is hereby incorporated by reference
in its entirety.
[0003] 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.
[0004] Consumers often desire to carry two separate items in a
storage container. For example, a consumer may store a salad in one
storage container and salad dressing in a separate container.
Conventional solutions for providing a single storage device for
holding multiple items have been proposed. U.S. Patent Publication
No. 2007/0102319 describes a one-piece container having a first
vessel and a second vessel permanently secured to and inside the
first vessel. In this design, the user may not be able to, for
example, pour salad dressing out of the inner vessel without
spilling the contents of the outer vessel. U.S. Pat. No. 6,302,268
describes a container having an insert chamber that may release its
contents into the container through a hole in the bottom of the
insert chamber. To fill the insert chamber, it must be removed from
the lid of the container, filled, capped and inserted, cap side
down, back into the container. When the insert chamber is not in
use, it must remain in place in the lid of the container, else the
lid of the container would have an opening and not seal the
contents within the container.
[0005] The present invention has as a general aim to provide
containers that satisfy both users and manufacturers.
[0006] Users would find it desirable to provide containers that
advantageously create a partial vacuum within the sealed storage
area of the container during use. Still further, users would find
it desirable a cover that holds items in place within the container
or that expands somewhat to accommodate larger items. Still
further, users would find it desirable to have covers that provide
for cover interlocking while at the same time allow for stacking of
additional containers on top of the cover of a first container.
Still further, users would find it desirable for a cover that may
cover both an outer container and an inner container, fitting
inside the outer container, simultaneously. What is needed is a
container of improved flexibility that can provide these
advantages.
SUMMARY OF THE INVENTION
[0007] In view of the foregoing, the present invention provides
containers whose covers can be stacked together in two 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.
[0008] The present invention further provides a container whose
cover may secure an outer container while simultaneously securing
an inner container positioned inside the outer container. The inner
container may sealingly engage with an inner closure mechanism in
the container cover. The outer container may sealingly engage with
an outer closure mechanism in the same container cover. The inner
closure mechanism may form a portion of a means for stacking the
covers together.
[0009] In some embodiments, the cover may include a first closure
portion, a third closure portion, an engagement portion, and an
alignment portion. The outer container may include a second closure
portion and the inner container includes a fourth closure portion.
The first closure portion of the cover may be sealingly engageable
with the second closure portion of the outer container to form a
substantially sealed, leak-proof, and re-sealable storage area for
items such as food. The outer surface of the alignment portion of
the cover is engageable with the inner surface of the alignment
portion of a second cover to form an aligned cover stack. The outer
surface of the engagement portion of the cover may be engageable
with the inner surface of the engagement portion of a second cover
to form a locked cover stack. The third closure portion of the
cover may be sealingly engageable with the fourth closure portion
of the inner container to define a substantially sealed,
lead-proof, and re-sealable storage area for items such as food,
condiments, or the like. The third closure portion of the cover may
be formed from the inner surface of the alignment and engagement
portions of the cover.
[0010] Further, the covers of the present invention may include
articulation elements that allow the covers to easily flex upwardly
or downwardly, sometimes referred to as articulate, either alone or
when engaged with the base of the container. A protruding
engagement portion of the cover may be articulated downwardly to
the level of the top of the remaining portions of the cover.
[0011] The covers and bases (e.g., inner and outer containers) 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 vacuum 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.
[0012] 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
[0013] FIG. 1 is an isometric view of a container with a cover and
a base according to an embodiment of the present invention;
[0014] FIG. 2 is a partially cut-away view of a container, showing
an inner container nested inside the base, according to an
embodiment of the present invention;
[0015] FIG. 3 is a cross-sectional isometric view of a round
container of the invention;
[0016] FIG. 4 is a cross-sectional isometric view of the
rectangular-shaped container of FIG. 2;
[0017] FIG. 5 is a top plan view of the cover of FIG. 1;
[0018] FIG. 6 is a bottom plan view of the cover of FIG. 1;
[0019] FIG. 7 is an isometric view of the base of FIG. 1;
[0020] FIG. 8 is an isometric view of the inner container of FIG.
2;
[0021] FIG. 9 is a partial isometric sectional view with the
engagement portion of the cover of FIG. 1 locking engaged with and
engagement portion of a second cover;
[0022] FIG. 10 is an isometric view of a container base;
[0023] FIG. 11 is a top plan view of the container base of FIG.
10;
[0024] FIG. 12 is a top plan view of a container cover;
[0025] FIG. 13 is a side sectional view of the container base of
FIG. 10 and the container cover of FIG. 12; and
[0026] FIG. 14 is an enlarged, detail view of a portion of FIG.
13.
DETAILED DESCRIPTION OF THE INVENTION
[0027] Turning to the drawings, wherein like reference numerals
refer to like elements, an embodiment of the present invention is
illustrated in FIGS. 1 through 8. A container 100 includes a
continuous, flexible cover 102 sealingly engaged to a outer
container 104. In the example of FIGS. 1 through 3, the container
100 is depicted as substantially circular in top plan view. In
other embodiments of the present invention, for example FIG. 4, the
container 100 can have other shapes such as rectangular, square, or
elliptical.
[0028] The cover 102 includes an engagement portion 106 that is
lockingly engageable with the engagement portion of a second cover
(not shown in FIG. 1, see FIG. 9). As described more fully below
with reference to FIGS. 10A through 13C, circumscribing the
engagement portion 106 of the cover 102 is at least one
articulation element 108. The engagement portion 106 of the Figures
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 106 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.
[0029] The continuous cover 102 includes a first closure portion
310 (FIG. 6). The first closure portion 310 is sealingly engageable
with a second closure portion 416 (FIG. 7) of the outer container
104. The first closure portion 310 of the cover 102 can be
sealingly engaged with a second closure portion 416 of the outer
container 104 to provide a leak-resistant, re-sealable closure.
When the first closure portion 310 of the cover 102 and the second
closure portion 416 of the outer container 104 are abutted and
sealingly engaged with each other, the cover 102 and the outer
container 104 define a substantially sealed storage area within
container 100 (FIG. 1).
[0030] The cover 102 includes a third closure portion 311 (FIG. 6)
which may be an inner surface of the engagement portion 106. The
third closure portion 311 is sealing engageable with a fourth
closure portion 417 (FIG. 8) of the inner container 105. The third
closure portion 311 of the cover 102 can be sealingly engaged with
the fourth closure portion 417 of an inner container 105 to provide
a leak-resistant, re-sealable closure. When the third closure
portion 311 of the cover 102 and the fourth closure portion 417 of
the inner container 105 are abutted and sealingly engaged with each
other, the cover 102 and the inner container 105 define a
substantially sealed storage area within the inner container
105.
[0031] As shown in FIGS. 2 through 4, the inner container 105, once
sealed to the cover 102, may fit inside the outer container 104 and
the first closure 310 of the cover 102 and the second closure
portion 416 of the outer container 104 may sealingly engage with
each other. This configuration may provide a substantially sealed
storage area within the inner container 105 removably nested inside
a substantially sealed storage area within the outer container
104.
[0032] The inner container 105 may have its own lid (not shown)
that may sealingly engage with the inner container 105. In this
configuration, an item, for example, salad dressing, may be stored
in the inner container 105 and covered with its lid. When a user
desires, the lid of the inner container 105 may be removed and the
inner container may be sealingly engaged with the cover 102 (FIGS.
2 through 4).
[0033] The inner container 105 may be pre-filled with an item, such
as a dip, dressing, condiment, or the like, and sealed at the time
of manufacturer. A user may unseal the inner container 105 and
sealingly engage the inner container to the cover 102 at the
appropriate time. For example, salad dressing may be pre-filled
into the inner container 105 and sealed with a foil seal. When the
user prepares a salad in the outer container 104, the user may
remove the seal on the inner container 105, attach the inner
container 105 to the cover 102 and seal the cover 102 on the outer
container 104. This configuration provides a convenient way to
carry a salad and salad dressing separately. When the user desires
to mix the salad and dressing, they may simply remove the cover 102
from the outer container 104 and remove the inner container 105
from the cover 102. The user may then simply pour the contents of
the inner container 105 onto the contents within the outer
container 104.
[0034] In an alternate embodiment, the inner container 105 may be
used to hold, for example, crushed ice. When the inner container
105 is sealed to the cover 102 and the cover 102 is sealed to the
outer container 104, the ice in the inner container 105 may help
keep cold the contents within the outer container 104. The same
concept may be used for keeping items warm. Alternatively, other
substances may be stored in the inner container 105, such as an
odor or moisture absorber. The inner container 105 may be gas
permeable to allow air to pass between the inner container and the
outer container 105.
[0035] The size of the inner container 105 may vary depending on
the desired use. In some embodiments, the inner container 105 may,
when sealingly engaged to the cover 102 and the cover 102 is
sealingly engaged to the outer container 104, come close to or
contact the bottom of the outer container 104 (FIG. 2). In other
embodiments, the inner container 105 may, when sealingly engaged to
the cover 102 and the cover 102 is sealingly engaged to the outer
container 104, be shorter and a gap 107 may be present between the
outer container 104 and the inner container 105 (FIG. 3).
[0036] As shown in FIG. 7, the outer container 104 of the container
100 includes a bottom 410 and a peripheral sidewall 412 extending
upwardly from the peripheral edge of the bottom 410. The top of the
outer container 104 is open. The second closure portion 416 of the
outer container 104, which, as noted above, is adapted to sealingly
engage with the first closure portion 310 of the cover 102 (FIG.
6), is positioned at the open end of the peripheral sidewall 412 of
the outer container 104. In one embodiment, the second closure
portion 416 of the outer container 104 is a raised locking ring
that extends from an upper edge of the peripheral sidewall 412 of
the outer container 104.
[0037] More particularly with reference to the engagement portion
106, the cover 102 illustrated in FIGS. 1, 5, 6 and 9 includes the
engagement portion 106 that allows the cover 102 to lockingly
engage with the engagement portion 506 of a second cover 502 to
form a locked stack of covers (FIG. 9). This locking feature makes
the resultant stack of covers more structurally rigid and thus less
precarious than a traditional, non-interlocked, stack of
covers.
[0038] A shown in FIG. 9 the cover 102 is locked together with the
second cover 502 by their engagement portions 106 and 506
respectively. In the example of FIG. 9, the engagement portion 106
of the cover 102 includes an upper protrusion 118 (see also FIG. 1)
and a lower protrusion 120. Further, the engagement portion 506 of
the second cover 502 likewise includes an upper protrusion 518 and
a lower protrusion 520. Each protrusion 118, 518, 120, and 520 is
convex on one side and concave on the other. The lower protrusion
120 of the cover 102 fits over and receives the upper protrusion
518 of the second cover 502, thus locking the covers 102 and 502
together. In this manner, the covers 102 and 502 are held together
and form a structurally stable cover stack. A third cover (not
shown) may be lockingly engaged with the second cover 502, a fourth
cover with the third and so on to form a stack of any number of
covers.
[0039] The engagement portion 106 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. Rotation, as
used herein, is defined about an axis A (FIG. 1) normal to the
plane formed by orthogonal midlines, i.e., first midline 205A and
second midline 205B at the top surface of the cover 102 as shown in
FIG. 5. The origin of the rotational axis is at the center point
207 at which the orthogonal midlines intersect. 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.
[0040] 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 portions or discretely segmented about the engagement
portions. In some embodiments, the force required to connect the
cover and the second cover 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
[0041] More particularly with regard to the first closure portion
310 and the second closure portion 416 forming the sealing
engagement of the cover 102 and the outer container 104, and to the
third closure portion 311 and the fourth closure portion 417
forming the sealing engagement of the cover 102 to the inner
container 105, FIG. 6 is a bottom plan view of the cover 102 of
FIG. 1. Referring to FIGS. 1, 6, 7 and 8, as noted above, the cover
102 of the container 100 may sealingly engaged with the outer
container 104 and the inner container 105 of the container 100. The
cover 102 includes the first closure portion 310 (FIG. 6) in the
form of receiver at the perimeter edge of the cover 102 adapted to
sealingly engage the second closure portion 416 in the form of the
raised locking ring at the top edge of the peripheral sidewall 412
of the outer container 104. The cover 102 further includes the
third closure portion 311 (FIG. 6) in the form of receiver at the
perimeter edge of the inner surface of the engagement portion 106
adapted to sealingly engage the fourth closure portion 417 in the
form of the raised locking ring at the top edge of the peripheral
sidewall 413 (FIG. 3) of the inner container 105. As a result, when
the cover 102 and the inner container 105 are abuttingly engaged, a
positive seal is formed between sealing surfaces around the
perimeters of the inner container 105 and of the cover 102. In this
embodiment, the container 100 uses a locking rim design that
includes both inside and outside seals. As would be apparent to one
of ordinary skill in the art however, the present invention can be
embodied with a variety of closure designs including outer closures
and/or inner closures. Related U.S. Patent Publication number
2008/0041850, co-owned with the present invention and incorporated
in its entirety herein by reference, further describes the closure
portions. However, the closure portions described therein are
examples only, and many other types of closure portions could be
used with the present invention.
[0042] The first and second closure portions 310 and 416 and the
third and fourth closure portions 311 and 417 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 310 and 416 and the third and fourth closure
portions 311 and 417 can provide a sealing engagement between the
closure portions. As a result, when the pieces are abuttingly
engaged, a positive seal can be formed between the first and second
sealing surfaces around the perimeters of the outer container 104
and of the cover 102 and between the third and fourth sealing
surfaces around the perimeters of the inner container 105 and the
cover 102. The sealing engagement of the closure portions can be
accompanied by an audible "snap" indicating that the container is
securely closed.
[0043] The outer container 104 and the inner container 105 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 outer container 104 and the inner
container 105 can be made from any suitable plastic and can be made
by any suitable technique, such as co-extrusion, lamination,
injection molding, vacuum thermoforming, or overmolding. In one
embodiment, the outer container 104 and the inner container 105 are
formed from polypropylene. As with the cover 102, the nominal wall
thickness of the outer container 104 and the inner container 105
can vary somewhat due to the manufacturing process.
[0044] The cover 102 of FIG. 1 can be constructed with a wall
thickness thinner than that of a outer container 104. The cover 102
can be made from any suitable plastic and can be made by any
suitable technique, such as vacuum thermoforming processes
described herein. In one embodiment, the cover 102 can be formed
from polypropylene. Due to the vacuum thermoforming process, the
wall thickness of the cover 102 can vary slightly over its nominal
thickness. A cover 102 with a nominal thickness less than the
nominal thickness of the outer container 104, however, reduces the
cost of material for the container 100. Further, with a thinner
cover 102, increased cover flexibility more easily accommodates the
removal of the cover 102 from, and the sealing engagement with, the
outer container 104. The cover 102 can maintain adequate
flexibility for proper sealing even during typical freezer
temperatures.
[0045] The container base 104 of FIGS. 10 and 11 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. Just as the engagement
portion 200 of the cover 102 of FIG. 12 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] FIGS. 13 and 14 present embodiments of a container 100 whose
cover 102 is sealingly engaged with its base 104. FIG. 13 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.
[0047] In the embodiments of FIGS. 13 and 14, 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.
[0048] FIG. 14 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.
[0049] 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.
[0050] As illustrated in FIG. 14, 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.
[0051] 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.
[0052] 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.
[0053] In the example of FIG. 14, 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. The cover 102 includes a
ridge 728 on the outer wall 708 of the first closure portion
700.
[0054] The cover 102 can be made by various plastic molding
processes, including but not limited to vacuum thermoforming and
injection molding. Vacuum thermoforming of the cover 102 is
typically the most economical means for forming the cover 102. As
is well know in the art, vacuum thermoforming involves the heating
a suitable plastic sheet of material to a temperature at which the
sheet becomes formable into a shape that is set as the plastic
sheet cools. As used herein, a suitable plastic sheet is a plastic
sheet that may be readily used by the vacuum thermoforming process.
The heated plastic sheet is made to conform to the surface features
of a single surface "male" tool by drawing the heated sheet of
plastic to the surface of the tool by the force of a vacuum applied
to the tool. In vacuum thermoforming, the sealed air space between
the heated plastic and mold is evacuated to draw the heated plastic
to contact the single male surface of the mold.
[0055] Typically, however, in vacuum thermoforming, the thickness
of the finished article formed by the process is nominally uniform.
A side cross-section view through the vacuum thermoformed article
reveals a substantially uniform thickness profile. The "bottom"
surface of the heated plastic sheet that contacts the tool surface
conforms to its shape. The "top" surface of the plastic element
formed in the vacuum thermoforming process does not contact a tool
surface and generally resides at a uniform distance from the bottom
surface of the plastic article. Only nominal thinning of the
plastic material occurs when it bends and stretches around curved
mold features to conform to the path of the curved surfaces of
these features. As used herein, a substantially uniform thicknesses
in side cross-sectional profile is a thickness in a plastic article
that is not sufficiently variable to preclude its manufacture with
typical prior art single male surface vacuum thermoforming
techniques. Conversely, a non-uniform thickness is a profile
thickness in an article that varies enough to preclude the
manufacture of the article with standard prior art vacuum
thermoforming techniques requiring instead other plastic molding
techniques such as injection molding.
[0056] Injection molding of a plastic article involves heating
suitable plastic material in the form of pellets or granules until
a melt is obtained. The melt is next forced into a split-die mold,
sometimes referred to as a split-die tool, where it is allowed to
"cool" into the desired shape. Both the bottom surface and the top
surface of the plastic article are formable by the split-die mold.
Thus, articles may by formed by the injection molding process that
have side cross-sectional profiles of varying non-uniform
thickness. After the plastic melt cools, the split-die mold is
opened and the article is ejected. Since, the mold is separable,
undercut surface on the plastic article may be relieved from the
split-die mold when it is opened. Injection molding, well know in
the art, is typically used to form plastic articles that have large
undercuts and substantially varying thicknesses in side
cross-sectional profile. As used herein undercuts are said to be
large if a molded plastic article having undercut features is
difficult or impossible to remove from a single-surface vacuum
thermoforming mold after it is formed and cooled.
[0057] Since cover 102 as described, contains significant
undercuts, such as included in upper protrusion 118 and lower
protrusion 120 (FIGS. 1 and 9) on the engagement portion 106 of the
cover 102, injection molding would typically be required to form
cover 102. Further, injection molding would typically be required
to form articulation elements 108 that are significantly thinner
than the rest of cover 102.
[0058] The container 100 can be reusable, but it can also be
constructed cheaply enough that consumers see it as a disposable
item, with replacement covers 102 and bases 104 available
separately for retail sale. The outer container 104 and the cover
102 can be fabricated by vacuum thermoforming a clarified
polypropylene homopolymer material. In another embodiment, the
container 100 may be fabricated by vacuum thermoforming a clarified
random copolymer polypropylene material. Other plastic materials
which would be suitable for fabricating the cover 102 and the outer
container 104 of the container 100 by vacuum thermoforming include
PS (polystyrene), CPET (crystalline polyethylene terephthalate),
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.
[0059] The container 100 may include a visual indication of closure
between the cover 102 and the outer container 104 and/or between
the cover 102 and the inner container 105. The visual indication
may be a color change in the area where the cover 102 engages the
outer container 104 and/or the inner container 105. In one
embodiment, the first closure portion 310 on the cover 102 may be a
first color and the second closure portion 416 on the outer
container 104 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 100 is
sealed.
[0060] The container 100 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.
[0061] The container 100 may include a self-venting feature. The
pressure in the sealed container 100 may increase when the sealed
container 100 and contents are heated in a microwave oven. Thus,
the cover 102 may include a self-venting mechanism, which opens
when the pressure in the container 100 exceeds a predetermined
value.
[0062] The container 100 may be divided to separate foods in the
container. A divider may be integral with the container 100 or may
be a separate component. Either the outer container 104 only may
include a divider or both the outer container 104 and the cover 102
may each include a divider. The divider located in the cover 102
may only partially engage the divider in the outer container 104 so
as to provide splash protection, or it may fully engage the divider
in the outer container 104 to provide varying degrees of
inter-compartmental leak resistance.
[0063] The container 100 may include a strip indicating the
temperature of the container 100 and its contents.
[0064] 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.
[0065] While the invention is described herein in connection with
certain preferred embodiments, there is no intent to limit the
present invention to those embodiments. For example, those of skill
in the art would recognize that may be formed such that the vertex
of the articulation element 108 is above the top of the cover 108,
that is the articulation elements 108 may be pointed upwardly. 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.
* * * * *