Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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CONTAINER AND LID ASSEMBLY
FIELD OF THE INVENTION
The technical field relates generally to container and lid assemblies, for
instance
container and lid assemblies that can be used in the commercial food
processing industry.
BACKGROUND OF THE INVENTION
Various kinds of containers have been suggested over the years. Many
containers
designed for holding food include a main bottom section forming a tray, a
dish, a bowl, a
receptacle or the like, and each container is hermetically sealed around or
near its top edges
by a wrapping and/or a lid to protect the contents during the transportation,
storage and
handling. Some containers are sold to customers without any contents therein
but others are
sold together with food items, for instance as prepackaged meals or the like.
Designing food containers for the commercial food processing industry can be
challenging. For instance, since most of these containers are only designed to
hold food
items until eaten by the customers, it is desirable that the quantity of
materials required for
making them and the manufacturing costs be minimized. Unfortunately, this is
not always
easy to achieve since the containers and their lids must also meet other
requirements, such as
resisting shipping, storage and handling, including handling at the stores or
the restaurants
where they are sold. The containers must remain intact and constantly sealed,
between the
packaging process and the moment customers open them, to avoid contamination
and
spoilage. On the other hand, adding too many packaging layers or features,
such as a
protective box made of cardboard or the like, or additional layers of
wrapping, to mention
just a few, increases the volume of waste material to be recycled and/or
discarded after their
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use. This situation is not desirable and it will likely dissatisfy many actual
or potential
customers.
Further difficulties and challenges in the design of food containers are
created when
these food containers must also be used for heating/cooking food items
directly therein, for
instance in a microwave oven. In a microwave oven, the heat generated inside
the food items
is transferred to the container itself and the temperature of the container
can eventually
become very high. Containers must still remain sufficiently rigid even when
heated at high
temperatures.
Even more challenging is the design of food containers used for
heating/cooking food
items directly therein and that can be reclosed after the initial opening by
the customer.
These food containers are used with lids that can be reclosed during
heating/cooking and/or
afterwards for transportation and storage. For example, some prepackaged meals
require
separate ingredients to be mixed and/or added before heating/cooling them,
such as a meal
where water must be added before heating/cooking. Some meals can also be
packaged with
ingredients that must be mixed together by the customer inside the container
but where not
all ingredients are mixed at the same time. An example is a stir-fry meal
where a sauce or
the like is added only after some cooking/heating time. Still, physical
interventions by the
customer during the heating/cooking process, for instance to stir the content,
may be another
reason to have a reclosable lid. Other situations exist as well.
Containers must perform well in the hands of customers but they must also be
easy to
handle at the packaging end, for instance, by the packaging equipment. Some
designs can be
adequate for transportation, storage and handling but far less for the
packaging process.
Difficulties in handling containers and sealing their lids can increase costs
and complexity of
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,
the packaging equipment and/or decrease the production rate.
Still, some container designs can create difficulties for the customers when
they
attempt to remove the sealed lid. Containers with rectilinear sides and
relatively sharp
corners are often difficult to handle when the lids are very light and
flexible.
Unfortunately, none of the previously-suggested containers has proven entirely
satisfactory to address many of the challenges encountered in the design of
containers,
particularly in the design of containers intended for the commercial food
processing
industry.
It is therefore clear that improvements in the related technical field are
still and will
always be needed.
SUMMARY OF THE INVENTION
According to one aspect of the present invention, there is provided a
container,
the container having a pair of side walls and a pair of end walls, corner
walls extending
between end walls and side walls, a flange formed on one of the corner walls,
a ring
member formed integrally with the flange, the ring being sized to sit on top
of the container.
According to a further aspect of the present invention, there is provided a
container
having at least one flange portion extending outwardly from a wall of the
container, the
flange having a proximal section adjacent the wall, the proximal section
having a recess
formed therein, a distal section remote from the wall, the distal section
having an upwardly
extending projection; and the upwardly extending projection being sized to fit
within the
recess.
The container and lid of the present invention may be utilized in many
different
applications. In particular, in several of the embodiments, the containers are
particularly
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suitable for the food industry and in particular, for packaging ready to use
foods.
The present embodiments of the present invention utilize containers which
normally
have a generally overall rectangular configuration. It will be understood, of
course, that
many different configurations can be utilized including those having various
arcuate
configurations.
The containers are formed of conventional plastic materials and the containers
are
normally formed using a thermoforming process. However, other known processes
may be
utilized.
The ring member of the present invention, in one embodiment, is formed as a
portion
of the container during a thermal forming process. The ring member is hingedly
connected
to the container and suitable retaining means may be utilized for securing the
lid member to
the top of the container.
In a further embodiment of the present invention, the ring member is formed as
part
of the container and is then separated from the container to become a separate
ring member.
BRIEF DESCRIPTION OF THE DRAWINGS
Having thus generally described the invention, reference will be made to the
accompanying drawings illustrating embodiments thereof.
Figure 1 is an exploded isometric view of an example of a container and lid
assembly
based on the proposed concept;
Figure 2 is an isometric view of the container and lid assembly in Figure 1,
where the
assembly is illustrated in a closed position;
Figure 3 is a top plan view of the container and lid assembly shown in Figure
2;
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Figure 4 is a view similar to Figure 2 but where the assembly is illustrated
in an
opened position as the lid is unconnected to the container;
Figure 5 is an enlarged isometric view of the area inside line 5-5 in Figure
4;
Figure 6 is a transversal cross section view taken along line 6-6 in Figure 2;
Figure 7 is an enlarged view of the area inside line 7-7 in Figure 6;
Figure 8 is a semi-schematic view of an example of a mold in which the
container
and the lid frame are molded together;
Figure 9 is a cross-sectional view of a variation of a lid frame;
Figure 10 is a top plan view of a bowl and flange when thermoformed;
Figure 11 is top plan view of the bowl and ring after the exterior edges are
folded;
Figure 12 is a partial sectional view illustrating a flange arrangement for a
recess and
a protrusion;
Figure 13 illustrates folding of an outer part of a flange to mate with an
inner portion
of the flange,
Figure 14 is a top plan view of a further embodiment of the container
according to the
present invention;
and
Figures 15 and 16 illustrate folding of the member of Figure 14 to mate with
the top
of the container.
DETAILED DESCRIPTION OF THE INVENTION
Figure 1 is an exploded isometric view of an example of a container and lid
assembly
100 based on the proposed concept. The assembly 100 is used for packaging a
product, for
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instance one or more food items. Although the proposed concept is especially
well adapted
for holding meals and other food items, it is possible to design and/or use
the assembly 100
for holding one or more products that are unrelated to the food industry. The
following
detailed description refers to the context of the commercial food processing
industry only for
the sake of simplicity.
As suggested by its name, the assembly 100 includes a container 102 and a
corresponding lid 104. The container 102 includes a main body 110 having one
or more
walls defining a hollow interior compartment 112 for storing the food items to
be packed
therein. The container 102 has an opening 114 at the top that is defined by
the inner edge of
an outwardly-projecting container rim 120. The container rim 120 is made
integral with the
main body 110. The top of the container rim 120 is at the horizontal in normal
use. The
opening 114 is substantially rectangular in shape, with rounded corners and
slightly curved
sides between the corners. Variants are possible as well. For instance, the
container 102
could have an opening with substantially straight sides and sharper corners,
an opening with
a nonrectangular shape, such as a rounded shape, a triangular shape or a shape
with more
than four sides, etc. Many other variants are possible as well.
In the illustrated example, the main body 110 includes a bottom wall and four
upwardly-disposed side walls configured to form a bowl or the like. The wall
or walls
forming the main body 110 are airtight and liquid tight.
It should be noted that the shape of the main body 110 of the illustrated
container 102
is only one example of implementation. Variants are possible.
The container 102 can be made using a thermoforming process or an injection
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molding process, for instance using a plastic material. Other materials and/or
manufacturing
processes can be used as well. The wall or walls forming the main body 110 of
the container
102 can be relatively thin and the container rim 120 will stiffen the
container 102, even if
the container rim 120 is also relatively thin to minimize the quantity of
material.
The lid 104 includes a ring-shaped lid frame 130 and a membrane 132 that will
be
attached over the lid frame 130 at some point of the packaging and/or
manufacturing
process. The lid frame 130 includes a relatively flat strip portion 134 having
a continuous
flat top surface and a continuous flat bottom surface. The periphery of the
membrane 132
will adhere to the top surface of the lid frame 130 to form an airtight and
liquid tight seal.
The lid 104 is thus made with a minimized quantity of material and will be
very light.
The lid frame 130 can be made using an injection molding process, for instance
using
a plastic material. Other materials and/or manufacturing processes can be used
as well.
However, the lid frame 130 is not molded directly to or over the container rim
120. The lid
frame 130 is only put in position onto the container rim 120 after the molding
process.
The membrane 132 is in the form of a thin film, for instance a plastic film or
a foil.
Other materials can be used as well, depending on the actual implementation.
The
membrane 132 can be transparent, translucent or opaque, depending on the
needs.
The lid frame 130 of the illustrated example also includes two diametrically
opposite
corner latching tabs 136, 138 that are each made integral with the outer side
edge of the lid
frame 130. Each latching tab 136, 138 has a proximal section that extends
outwards from the
side edge of the flat strip portion 134 and a distal section that extends
downwards. The
latching tabs 136, 138 are designed to prevent them from interfering with the
continuity of
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the contact of the bottom surface of the flat strip portion 134 with the outer
peripheral top
surface 122 when it rests thereon. The lid frame 130 of the illustrated
example also includes
a lift tab 140 that is made integral with the free end of the distal section
of the first corner
latching tab 136. Only one lift tab is provided in the illustrated example.
The lift tab 140
extends horizontally outwards from the distal portion of the first corner
latching tab 136.
Variants are possible as well.
As can be seen, the lid 104 is devoid of a peripheral skirt or the like. The
size of the
latching tabs 136, 138 is also kept to a minimum. Overall, this will greatly
facilitate the
opening and closing of the lid 104. A lesser force is required to handle it
and as a result, it is
less likely to undergo a plastic deformation because the customer exerted an
excessive
pulling force. The lid frame 130 is relatively small and can be prone to
deformation when
subjected to an excessive pulling force.
Figure 2 is an isometric view of the container and lid assembly 100 in Figure
1,
where the assembly 100 is illustrated in a closed position. The lid 104 is
then attached to the
container 102, more specifically to the container rim 120. In Figure 2, the
membrane 132 is
sealingly attached to the lid frame 130.
Figure 3 is a top plan view of the container and lid assembly 100 shown in
Figure 2.
Figure 4 is a view similar to Figure 2 but where the assembly 100 is
illustrated in an
opened position. The lid 104 is then unconnected to the container 102.
As can be seen, for instance in Figures 3 and 4, the top side of the container
rim 120
includes an outer peripheral top surface 122 and an inner peripheral top
surface 124. Each of
these surfaces 122, 124 are flat and continuous. They are also substantially
horizontal in
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normal use. However, the outer peripheral top surface 122 is slightly
vertically below the
inner peripheral top surface 124 so as to receive the bottom surface of the
lid frame 130
when the lid 104 is in a closed position. These mating surfaces are configured
and disposed
to form an uninterrupted seal around the entire perimeter of the container rim
120.
Figure 5 is an enlarged isometric view of the area inside line 5-5 in Figure
4. As can
be seen, the outer peripheral top surface 122 includes a through hole 150 at
the corner where
the first latching tab 136 is located when the lid 104 is in a closed
position. A similar hole
150 is also provided at the opposite corner, thus at the corner where the
second latching tab
138 is located. In the illustrated example, these holes 150 have an oblong
shape that is
generally oriented parallel to the medial axis of the outer peripheral top
surface 122.
Variants are possible as well. For instance, the holes 150 can be provided
with other shapes,
including for instance a "lens" shape to help in aligning the studs 152 at the
center of the
holes 150.
Figure 5 also shows that the container rim 120 of the illustrated assembly 100
includes a downwardly projecting skirt 126 extending around the entire
periphery of the
container 102. The skirt 126 promotes rigidity. Variants are possible as well.
Figure 6 is a transversal cross section view taken along line 6-6 in Figure 2.
It thus
shows the lid 104 in a closed position. Figure 7 is an enlarged view of the
area inside line 7-7
in Figure 6. As can be seen, these figures show one of the studs 152 provided
to engage the
inner edge of a corresponding hole150, as best shown in Figure 7. A similar
stud 152 is
provided at the opposite corner to engage the other hole 150. These studs 152
have a
substantially circular cross section in the illustrated example. The
engagement of the
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studs 152 with their corresponding holes 150 can be an interfering engagement,
including for
instance using a notch (not shown) or the like to create a snap fit
interlocking connection.
This removable interfering engagement will create a retention force resisting
the lifting of the
lid 104 and interlocking the lid 104 with the container 102. However, the
interfering
engagement can be removed upon lifting the lid frame 130 using a mild force.
Using the studs
152 and the corresponding holes 150 also greatly facilitates the closing of
the lid 104 since
the lid frame 130 is made of a relatively flexible part. It can become very
flexible at high
temperatures and the studs 152 can facilitate the positioning. The customer
can used their
thumbs to urge the studs 152 into the holes 150 when closing the lid 104.
Variants are
possible as well.
The latching tabs 136, 138 also help in centering the lid 104 on the container
102 and
they can be shaped to engage, with a mild interfering force, the bottom edge
of the skirt 126.
Each latching tab 136, 138 can be provided with an undercut (not shown) or a
similar feature
to create an interlocking connection with the bottom edge of the skirt 126.
They can even
replace the studs 152 and their holes 150 in some implementations. Variants
are possible as
well.
The holes 150 have an oblong shape in the illustrated example. This feature is
to
facilitate the positioning by the customer. Variants are possible as well.
Figure 7 also shows that the top surface of the lid frame 130 and the inner
peripheral
top surface 124 of the container rim 120 are substantially flush with one
another when the lid
104 is in a closed position. The bottom surface of the membrane 132 is then
directly above
the inner peripheral top surface 124.
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Still, Figure 7 shows that the inner side edge of the flat strip portion 134
is spaced
apart from the outer edge bordering the inner peripheral top surface 124. This
space can
provide more room for aligning the parts when they are hot. The space also
provides an
increase of the manufacturing tolerances, thus mitigating the risks of having
parts being
rejected because they are too wide after the molding process.
During the packaging process, the item or items can be put inside the hollow
interior
compartment of each container 102 with the lid frame 130 being already in an
interlocking
engagement with the container rim 120. This previous step can be achieved by
hand or by
appropriate equipment. The containers 102, with their lids 104 thereon, can
still be stacked so
as to minimize space. Variants as possible as well.
An interesting benefit of the proposed concept is that since no peripheral
skirt is
provided on the lid 104, the handling of the container 102 with the pre-
connected lid
frame 130 during the packaging process is made easier since a stack of these
parts can be
supported anywhere underneath the container rim 120, with the exception of the
two corners
with the latching tabs 136, 138 are provided, without the risks of
accidentally lifting a portion
of the lid frame 130 from the container rim 120.
The membrane 132 is added at the end of the packaging process to
simultaneously
form the lid 104 and to seal the whole assembly 100. For instance, if the
membrane 132 is
made of a thermoplastic material, the membrane 132 can be heated and pressure
can be
applied so as to simultaneously bond the outer perimeter of the membrane 132
to the outer
and inner peripheral top surfaces 122, 124. This can be done in a single
operation during
which the underside of the container rim 120 is supported by a die while the
membrane 132 is
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urged onto the lid frame 130 and onto the exposed inner peripheral top surface
124 by a
heated pressure plate. The combination of heat and pressure bonds the membrane
132 over
the top surface of the lid frame 130 and over the inner peripheral top surface
124.
If desired, the inner peripheral top surface 124 can be positioned slightly
lower than
the top surface of the flat strip portion 134 when the lid 104 is in a closed
position. This will
make the bond between the inner peripheral top surface 124 and the membrane
132 slightly
weaker than the bond between the top surface of the flat strip portion 134 and
the membrane
132. Still, as shown in Figure 7, the width of the outer section of the
membrane 132 that is
fused onto the top surface of the flat strip portion 134 is larger than the
width of the adjacent
inner section of the membrane 132 that is fused onto the inner peripheral top
surface 124.
These features will make the membrane 132 less prone to detach from the lid
frame 130
during the initial unsealing of the assembly 100 by the customer and will also
decrease the
required pulling force. This decrease of the pulling force can mitigate the
risks of accidentally
tearing the membrane 132 when the assembly 100 is unsealed. Variants are
possible as well.
In use, to open the sealed assembly 100, the customer will move the lift tab
140
upwards to create a peeling force that will progressively detach the membrane
132 from the
inner peripheral top surface 124 of the container rim 120, starting at the
corner adjacent to the
lifting tab 140. The membrane 132 will stay attached on the lid frame 130
since the peeling
motion will only remove the membrane 132 from the inner peripheral top surface
124. Thus,
it is relatively easy for the customer to lift a corner of the lid 104 using
the lift tab 104 and
then lift the whole lid 104 to access the interior of the container 102. This
way, the customer
can add liquids or other ingredients, for instance additional ingredients from
a pouch or the
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like. The lid 104 can be reclosed before continuing the heating/cooking
process.
Figure 8 is a semi-schematic view of a mold 200 in which the container 102 and
the lid
frame 130 are molded together in a same injection shot of molten plastic
material but in
separate cavities. The mold 200 includes a first cavity 202 for the container
102 and a second
cavity 204 for the lid frame 130. Both cavities 202, 204 are in fluid
communication using an
intervening channel 206. The channel 206 will also be filled with the molten
plastic material
after the injection shot and as the plastic material solidifies, it will form
a connector linking
the outer edge of the container rim 120 to the outer edge of the lid frame
130. This connector
206 can be removed or cut to completely separate the container 102 and the lid
frame 130.
However, one can also keep the connector 206 to facilitate handling during the
packaging
and/or by the customer, provided that the connector 206 remains relatively
flexible at room
temperature and is located at the corner opposite the corner with the lift tab
140. The
connector 206 can be useful for keeping the orientation of the lid frame 130
with reference to
the container 102 and for preventing a customer from attempting to close the
lid 104 while
the studs 152 are at the corners where no holes are present.
Figure 9 illustrates an alternative embodiment in which an injection molded
snap
ring 208 is placed on top of a flange 210 to a thermoformed bowl. The flange
210 is welded
to the thermoformed bowl. The ring can also be welded directly to the
container so that when
one opens the lid, the film will stick to the ring, but the ring will be
detached from the
container. The ring will also snap in the flange. Preferably, the flange and
ring are injected
molded.
Alternative embodiments are illustrated in Figures 10 to 14.
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Referring to the embodiment of Figures 10 and 11, there is illustrated a bowl
or
container 312, includes a base 314. Extending upwardly from base 314 are pair
of side walls
316 and a pair of end walls 318. At the point of joinder of and end wall 318
with a side wall
316, there is provided bend lines 320 which form corner walls 322. Each corner
wall is
located near a respective side wall 316 and end wall 318.
Extending outwardly from side walls 316, end walls 318 and corner walls 322
there is
a flange which has an inner or proximal flange portion 324 and an outer or
distal flange
portion 326. Between distal portion 326 and proximal portion 324, there is a
crease or fold
line 328 to permit distal portion 326 to fold over on top of proximal portion
324. Inner or
proximal portion 324 is provided with recesses 330 while distal or outer
portions 326 are
provided with a protrusion 332. Protrusions 332 are designed to mate with
recesses 330 and
lock the two pieces together.
As has previously been described, container 312 is provided with a upwardly
extending top surface 323. Top surface 323 extends above proximal flange
portion 324 and
distal flange portion 326. This arrangement permits the membrane layer (not
illustrated)
secured to the flange portions to seal against upper surface 323.
In the embodiment of Figures 12 and 13, there is illustrated a portion of a
bowl or a
container which has a base 364 and a side wall 366 extending therefrom. The
illustration
includes a inner or proximal flange portion 368 and an outer or distal flange
portion 370.
Proximal flange portion 368 includes recesses 372 while distal flange portion
370 includes a
protrusion 374 designed to mate with recess 372. This is done by folding of
the distal flange
372 over top of proximal flange portion 368.
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A further embodiment is illustrated in Figures 14 to 16. In this embodiment,
there is
provided a bowl or container 338 which has a base or bottom 340. Extending
upwardly from
base 340 are a pair of side walls 332 and a pair of end walls 344. Creases 346
are provided to
form corner walls 348. The top of the container includes an upper wall 350.
At one of the corner walls 348 there is provided a hinge 352 which is
connected to ring
member 356. Ring member 356 has protrusions which are designed to seat in
recesses 354 of
a flange 360. As has been previously described in the embodiments, there is
also an upper
wall 350 which is of a height to seat the above flange 360. A flexible
membrane (not shown)
is also utilized.
It will be understood that the above described embodiments are for purposes of
illustration only and that changes and modifications may be made thereto
without departing
from the spirit and scope of the invention.
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