Note: Descriptions are shown in the official language in which they were submitted.
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COLLAPSIBLE CONTAINER AND BLANK THEREFOR
TECHNICAL FIELD
[0001] The present invention relates to the field of containers such as
disposable paperboard cartons that may be shipped and stored in a flattened,
collapsed configuration and then opened into an uncollapsed, open
configuration
for use. More specifically, the present invention relates to a generally prism-
shaped container having a sealable opening for receiving food or other
articles.
BACKGROUND
[0002] In the food industry, disposable paperboard cartons are often used
in connection with prepared foods such as sandwiches, microwaveable foods
and the like. Food and other perishable items can be safely shipped and
displayed in rigid containers that also provide an attractive display to the
consumer. For example, single-serve items such as sandwiches are often
packaged in individual containers and stored in refrigerated displays. The
container is typically configured to closely fit the article, such a prism-
shaped
container with triangular sidewalls to closely fit a triangular sandwich. The
container typically includes a panel or lid that can open for access to the
interior
and which can be sealed shut. The panel or lid may include a window covered
with a transparent material to display the contents.
[0003] Disposable containers are often manufactured from blanks which
are cut out from a sheet of material and folded to assemble the finished
container. The material used to form the blank, along with the construction of
the container, is selected to provide sufficient strength and resistance to
leakage.
[0004] Efficient and cost-effective shipping, handling and storage of
empty
containers prior to filling can be a challenge. In some cases, unfilled
containers
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can nest to reduce space. In other cases, the container is stored in a flat
configuration and opened up into a three dimensional configuration prior to
filling. In such cases, the container may be partially assembled by adhering
together certain of the panels, with assembly being completed by transitioning
the container to its three-dimensional shape, which in some cases includes
additional adherence steps.
[0005] For food use, the container should have a sealable lid. This
prevents leakage or contamination and for some applications permits the
atmosphere within the container to be replaced with an inert gas such as
nitrogen to slow spoilage. As well, the joints of the container where panels
meet should be substantially sealed to prevent leakage and contamination.
Within the interior of the container, it is desirable to minimize locations
where
food can be trapped, such as glued layers of material.
[0006] Disposable containers are often shaped to match the shape of the
articles contained within. In the case of diagonally cut sandwiches, this
often
requires a triangular prism shape. Examples are disclosed in WO 2007/012880
Al by Goldman, U.S. Patent No. 6,695,202 by Miess, GB 2,425,524 A by Rokov,
and U.S. Patent Nos. 7,597,238 and 6,431,365 by Money et al.
[0007] The triangular prism shape of such containers can pose difficulties
in terms of providing a blank that can be efficiently and easily fabricated
into an
assembled container in the folded configuration, and then easily converted
into
the unfolded open configuration. The container should also include a lid which
can be securely sealed whereby the fully assembled and filled container is
substantially sealed. It is also desirable to provide a container design that
can
be easily modified to fit different sizes of articles, for example a
relatively thin
container to hold thin sandwiches and a wider container for wider sandwiches,
all with the same basic configuration of cardboard blank. It is desirable to
provide a blank that can be easily fabricated using a minimum amount of
material and cuts and folds. It is further desireable to provide a blank which
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can be assembled into a container with a minimum number of steps, gluing, or
fastening of parts.
[0008] It is further desirable to provide a container in which the
assembled blank may be folded into a compact flat configuration prior to use,
for storage, transport and the like. Preferably, the design of the blank
should
allow the container to be easily transitioned from a flat configuration for
storage
to a three dimensional configuration for use as a container. In some cases it
is
desirable for the container to be able to fold into the compact, flat
configuration
by folding sidewalls either inwardly or outwardly depending on the
requirements
of the user and other factors.
SUMMARY OF THE INVENTION:
[0009] The present invention relates to a blank as well as a folded
partially
assembled container and an assembled container formed from said blank. The
invention also relates to a method of assembling a container from a blank.
[0010] According to one broad aspect, the invention provides a blank for
forming a container in a generally triangular prism shape having an opening
for
receiving an article. The blank includes a quadrilateral end panel having
first
and second opposing sides, third and fourth opposing sides, and a longitudinal
axis extending from the third side to the fourth side; a generally triangular
first
side panel having first, second and third sides, said first and third sides
meeting
at an apex, said first side panel joined by a hinge along its first side to
the first
side of the end panel and comprising a central fold extending from the apex to
an intermediate point on the second side of the first side panel whereby said
first side panel is subdivided into two essentially equal triangular portions
that
can be folded either inwardly or outwardly; a second side panel comprising a
mirror image of the first side panel about the longitudinal axis, the second
side
panel joined by a hinge to the second side of the end panel; first and second
flaps joined by a hinge to the third side of the first and second side panels,
respectively, said flaps being aligned whereby when said side panels are
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inwardly folded along their respective hinges to be parallel to each other,
said
flaps overlie each other to form an end wall which opposes the quadrilateral
end
panel when the blank is formed into the container; and a lid connected by a
hinge to the third side of the quadrilateral end panel for closing the opening
when the blank is formed into the container. The end panel and lid are aligned
along the longitudinal axis and the first and second side panels extend
laterally
outwardly from said axis. The assembled, container is formed in flattened
configuration by fastening the flaps together in overlying relationship and
folding the triangular portions of said side panels together in overlying
relationship by folding said first and second side panels inwardly or
outwardly
along the central fold lines thereof.
[0011] According to another broad aspect, the invention provides a blank
for forming a container in a generally triangular prism shape having an
opening
for receiving an article. The blank includes a quadrilateral end panel, the
quadrilateral end panel having first and second opposing sides and third and
fourth opposing sides; a generally triangular first side panel having first,
second,
and third sides, the first side panel hinged along its first side to the first
side of
the quadrilateral end panel and comprising a first central fold line extending
from a vertex of the first and fourth sides of the quadrilateral end panel to
an
intermediate point on the second side of the first side panel; a generally
triangular second side panel having first, second, and third sides, the second
side panel hinged at the first side of the second side panel to the second
side of
the quadrilateral end panel and comprising a second central fold line
extending
from a vertex of the second and fourth sides of the quadrilateral end panel to
an
intermediate point on the second side of the second side panel; a first flap
hinged to the third side of the first side panel and a second flap hinged to
the
third side of the second side panel, wherein the first and second flaps form a
panel that opposes the quadrilateral end panel when the blank is formed into
the container; and a lid hinged to the third side of the quadrilateral end
panel
for closing the opening when the blank is formed into the container.
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[0012] According to another broad aspect, the invention provides a
container having a generally triangular prism shape and an opening for
receiving an article. The container includes a quadrilateral end panel having
first and second opposing sides, third and fourth opposing sides, and a
longitudinal plane substantially normal to the quadrilateral end panel; a
generally triangular first side panel having first, second and third sides,
said first
and third sides meeting at an apex, said first side panel joined by a hinge
along
its first side to the first side of the end panel and comprising a central
fold
extending from the apex to an intermediate point on the second side of the
first
side panel which substantially bisects said second side whereby said first
side
panel is subdivided into two essentially equal triangular portions that can be
folded inwardly or outwardly; a second side panel comprising a mirror image of
the first side panel about the longitudinal plane, the second side panel
joined by
a hinge to the second side of the end panel; first and second flaps joined by
a
hinge to the third side of the first and second side panels, respectively,
said
flaps being aligned whereby when said side panels are inwardly folded along
their respective hinges to be parallel to each other, said flaps overlie each
other
to form an end wall which opposes the quadrilateral end panel; and a lid
connected by a hinge to the third side of the quadrilateral end panel for
closing
the opening of the container. The container is formed by fastening said flaps
together in overlying relationship and folding the triangular portions of said
side
panels together in overlying relationship by folding said first and second
side
panels inwardly or outwardly along the central fold lines thereof.
[0013] According to yet another broad aspect, the invention provides a
container having a generally triangular prism shape and an opening for
receiving an article. The container includes a quadrilateral end panel, the
quadrilateral end panel having first and second opposing sides and third and
fourth opposing sides; a generally triangular first side panel having first,
second,
and third sides, the first side panel hinged along its first side to the first
side of
the quadrilateral end panel and comprising an first central fold line
extending
from a vertex of the first and fourth sides of the quadrilateral end panel to
an
intermediate point on the second side of the first side panel; a generally
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triangular second side panel having first, second, and third sides, the second
side panel hinged at the first side of the second side panel to the second
side of
the quadrilateral end panel and comprising a second central fold line
extending
from a vertex of the second and fourth sides of the quadrilateral end panel to
an
intermediate point on the second side of the second side panel; a first flap
hinged to the third side of the first side panel and a second flap hinged to
the
third side of the second side panel, wherein the first and second flaps form a
panel that opposes the quadrilateral end panel; and a lid hinged to the third
side
of the quadrilateral end panel for closing the opening of the container.
[0014] In some embodiments, the container or blank further includes a
third flap hinged to the fourth side of the quadrilateral end panel for
covering
the apex of the quadrilateral end panel and the opposing panel formed by the
first and second flaps. In some embodiments, the third flap is sandwiched
between the first and second flaps when the container is assembled.
[0015] In some embodiments, the first and second flaps can be secured to
one another on a single face of the container, preferably at a single point of
attachment using an adhesive or by heat sealing.
[0016] In another broad aspect of the invention, there is provided a
method of forming a generally triangular prism-shaped container having an
opening for receiving an article. The method includes providing a blank as
described above; folding said first and second side panels inwardly or
outwardly
along the central fold thereof; and securing the first and second flaps to one
another in overlying relationship, preferably at a single point of attachment.
[0017] Directional terms such as "front" and "rear", "top" and "bottom",
"first" and "second", "right" and "left" are used herein purely for
convenience of
description. Such terms are used for illustration purposes and are not
intended
to limit the present disclosure. As well, and dimensions herein are not
intended
to limit the scope of the invention unless specifically stated. Furthermore,
geometric terms such as "straight", "flat", "point" and the like are not
intended
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to limit the invention to the level of geometric precision, but should instead
be
understood in the context of the invention which includes such departures from
geometric position as the relatively high manufacturing tolerances that are
normal and/or acceptable in the field of this invention, as well as the
functional
requirements of products in the field of the invention wherein a high level of
precision may not be required.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG 1 is a plan view of a blank according to a first embodiment of
the present invention.
[0019] FIG 2A is a plan view of a container formed from the blank of FIG
1, which has been folded into a first flat configuration wherein the sidewalls
are
folded outwardly.
[0020] FIG 2B is a plan view of a container formed from the blank of FIG
1, which has been folded into a second flat configuration wherein the
sidewalls
are folded inwardly.
[0021] FIG 3 is a perspective view of a container formed from the blank of
FIG 1, in an unfolded configuration for filling and sealing.
[0022] FIGS 4A-D are plan views of blanks according to further
embodiments of the present invention, showing various alternative window
designs and other alternative aspects.
[0023] FIGS 5A-D are plan views of blanks according to still further
embodiments of the present invention.
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DETAILED DESCRIPTION
[0024] Referring to FIG 1, a blank 100 is provided which can be
assembled into a container 101, as seen in Figure 3. Figures 2A and 2B show
an assembled container 101 in a folded, flattened configuration.
[0025] Blank 100 typically consists of a flat sheet of cardboard or
similar
rigid or semi-rigid material. The material should have sufficient rigidity
whereby
when formed into an assembled container 101, it provides a suitable level of
protection and crush-resistance for the intended use of the container. Blank
100 may be cut or stamped from a continuous roll or large sheet of material
using conventional techniques. Blank 100 may also be formed from a food-
grade material and may comprise a coating on at least one side (which
ultimately may form the inside of the container 101) to prevent leakage from
the container 101 or contamination from entering the container 101. The
coating may also permit components of the blank 100 to be heat-sealed
together, as discussed below.
[0026] Blank 100 comprises in general terms an array of panels that are
connected together by fold lines, usually referred to herein as "hinges". When
assembled, the panels form walls of the container101, as discussed below.
When blank 100 comprises a single continuous sheet, as illustrated herein,
then
the hinges will comprise fold lines within the blank 100. However, it will be
understood that blank 100 may comprise separate panels, in which case the
hinges may comprise separate hinge members that join together the individual
panels.
[0027] Blank 100 comprises in general terms a generally rectangular end
panel 105, two triangular side panels 110 and 115 that oppose each other, a
generally rectangular lid panel 140, generally rectangular bottom flaps 120,
130 that protrude from the side panels 110, 115, and a central flap 125 which
protrudes from end panel 105. Lid 140 panel has an exposed end edge 143.
For purposes of reference, blank 100 has an elongate axis "a" that extends
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between end edge 143 and central flap 125. Lid panel 140, end panel 105,
and central flap 125 are longitudinally aligned along axis a.
[0028] As described below, the blank 100 may be assembled into a
container 101 which can transition from a flattened configuration, shown in
Figures 2A and 2B to an open position for filing, as seen in Figure 3. When
container 101 is unfolded into the open configuration, lid 140 can be closed
to
retain an article within the container 101 and sealed shut. Since blank 100 is
normally formed from a continuous sheet of material, the respective panels are
normally continuous with each other and are defined by fold lines within blank
100.
[0029] End panel 105 connects to opposing side panels 110 and 115
along fold lines 106 and 107 located along opposing sides of end panel 105
and protrudes laterally therefrom. Fold lines 106 and 107 permit side panels
110 and 115 to fold inwardly via valley folds. Each opposing side panel 110
and 115 is joined to a corresponding bottom flap, 120 and 130 respectively, at
fold lines 117 and 112, respectively.
[0030] A central flap 125 extends from the end panel 105 at a fold line
109. Central flap 125 seals the exposed edge of end panel 105 to reduce the
likelihood of leakage. Central flap 125 is located between bottom flaps 120
and
130, whereby the respective flaps 120, 125 and 130 may be sandwiched
together and secured to form a bottom wall of the container, as described
below.
[0031] End panel 105 is generally rectangular in shape, and in some cases
may be trapezoidal to improve stacking of the container 101 once assembled.
The width of end panel 105 may be selected to vary the dimensions of
container 101 to accommodate a selected article. For example, in the blanks
100, 200 shown in FIGS 1 and 4, the end panel 105, 205 is dimensioned to
provide a relatively wide container. In the blank 300 shown in FIG. 5, a
narrower end panel 305 is provided for a narrower container. Further
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variations can be also made to provide a container 101 having a triangular
prism shape of desired side to side depth to accommodate, for example,
sandwiches of differing thicknesses.
[0032] Side panels 110 and 115 are generally triangular in shape and are
essentially mirror images of each other so as to provide the finished
container
101 with a triangular prism shape. Side panels 110 and 115 consist of right
angle triangles in the present embodiment. Each side panel 110, 115 is
defined by an apex 121, a first side defined by fold lines 107,106 at the
junction with the end panel 105, a second side defined by fold lines 112, 117
at the junction with the bottom flaps 120, 130, and a hypotenuse 129.
[0033] In other embodiments, side panels 110 and 115 may be isosceles
or equilateral triangles. Scalene triangles may also be used for side panels
110
and 115, so long as the end panel 105, the opposing bottom wall formed by
the flaps 120 and 130 and the lid 140 are of differing lengths.
[0034] Side panels 110 and 115 are each substantially bisected by an
apical fold 111, 116 which extends from apex 121 to an intermediate point on
the hypotenuse 129. Apex 121 is located at the junction between the end
panel 105, the central flap 125, and a respective side flap 120, 130. Where
the intermediate point is the midpoint of the hypotenuse 129, these folds 111
and 116 bisect side panels 110 and 115, respectively, creating two equal
triangular sub-panels 110a/110b and 115a/115b.
[0035] Folds 111 and 116 act as hinges to permit container 101 to be
unfolded from an essentially flat, semi-assembled (flattened) configuration
(FIG
2A-2B) into a fully open configuration (FIG 3) wherein the container can
receive
a food article or other contents. Fold lines 111 and 116 are substantially
perpendicular to the periphery of their respective side panels 110 and 115.
Folds 111 and 116 may fold outwardly as seen in Figure 2A or inwardly as seen
in Figure 2B. This allows the same container 101 to be folded in two different
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ways depending on requirements such as storage limitations, equipment and
other factors.
[0036] Bottom flaps 120 and 130 form a bottom wall of container 101
when secured together in overlying fashion, as seen in FIG 3. In the blank 100
seen in FIG 1, flap 130 is continuous with side panel 110 and extends from
fold
line 112 thereof.
[0037] Flanges 131, 113 and 118 extend from the opposing side panels
110, 115 and one or more cooperating end panels 120 and 130 to provide an
outwardly-protruding shelf around the open mouth of container 101 to which lid
140 can be sealed.
[0038] In FIG 1, flange 131 protrudes laterally from a side edge of bottom
flap 130 and is continuous with flange 113 of side panel 110. In blank 100,
bottom flap 120 is not provided with a similar flange, since when container
101
is assembled, the corresponding side edge flap 120 is unexposed. In FIGS 4-5,
the flange 231/331 is divided into two portions 231a/331a and 231b/331b
provided on bottom flaps 220/230 and 320/330, respectively.
[0039] Lid 140 is substantially rectangular, but may be provided with
rounded corners. Lid 140 is joined to the end panel 105 opposite central flap
125, at fold line 108. The exposed edge regions of lid 140 contact flanges
113, 118, 131 when the lid 140 is closed. When a container 101 is assembled
from the blank 100, the flanges 113, 118, 131 are positioned along the
opening of the container 101 and serve as a surface upon which the lid 140 can
be sealed.
[0040] Lid 140 and flanges 113, 118 and 131 may be sealed together
with a heat sealable material such as a film or coating laminated to one side
of
blank 100. Alternatively, lid 140 may be secured to the flanges 113, 118, 131
with a suitable adhesive or mechanical closure.
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[0041] Where heat sealing is used to seal the lid 140, the heat seal is
conventionally formed by the application of heat and pressure to the lid 140
and flanges 113, 118, 131. A heat sealable film may be limited to areas that
are to be heat sealed or alternatively the blank may comprise a continuous
layer
of heat sealable film, which may also provide gas and/or liquid impermeability
to the material. Other materials for manufacturing a blank 100, such as
plastics, may also be suitable for heat sealing without requiring the
application
of an additional heat sealable film.
[0042] Lid 140 includes a window 150 to permit the contents of the
container 101 to be viewed. Window 150 is normally covered with a clear film.
In the blanks 100, 200 and 300 shown in FIGS 1, 4A and 5A, windows 150,
250 and 350 are generally rectangular in shape. Other sizes and configuration
for windows 150, 250 and 350 are depicted in FIGS 4B-4D and 5B-5D. It will
be seen that lid 140 may be provided with a large variety of window
configurations. As well, similar windows may be provided as appropriate in
other panels such as side or end panels 105, 110 and/or 115.
[0043] As seen in figures 2A and 2B, blank 100 is initially assembled into
container 101 by fastening bottom flaps 120 and 130 together in overlying
relationship, preferably using an adhesive. Other means of attachment are
also contemplated, including heat sealing in embodiments where the blank is
formed from a heat sealable material such as plastic or a paperboard material
having a heat sealable film or layer. Central flap 125 may be sandwiched
between bottom flaps 120 and 130.
[0044] In FIG 2-3, the larger bottom flap 130 overlies central flap 125
and bottom flap 120 such that the larger bottom flap 130 is exposed on the
inside of container 101 when unfolded. This arrangement provides a generally
continuous inner surface to the container 101 and sandwiches central flap 125
between flaps 120 and 130 for added structural integrity. The sequence of
layering can be varied from the above.
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[0045] Blank 100 is configured such that the assembled container 101
may be formed by securing bottom flaps 120 and 130. Where a central flap
125 is provided on the blank 100, it can also be secured to the bottom flaps
120 and 130 for added structural integrity. By gluing these flaps together,
blank 100 may be assembled into a container 101 in a three dimensional
container ready for filing with a food article or a flattened configuration
for
transport and storage.
[0046] This simplicity of assembly can reduce the complexity of the
machinery and materials required for fabrication of the container. For
example,
container 101 can be fabricated from the blank 100 in FIG 1 by fastening flaps
120, 125 and 130 together. No further fastening steps are required until the
lid is sealed to the filled container.
[0047] Depending on the configuration and dimensions thereof, container
101 may be folded into one of two flat configurations. FIG 2A depicts a first
flat
configuration in which the side panels 110 and 115 are folded outwardly along
fold lines 111 and 116. FIG 2B depicts a second flat configuration in which
the
side panels 110, 115 are folded inwardly along apical fold lines 111 and 116
by interweaving subpanels 110a/110b with 115a/115b or vice versa.
[0048] The first flat configuration shown in FIG 2A may be preferable in
applications where it is desirable to minimize the number and complexity of
folding actions when preparing the container 101. The second flat
configuration
shown in FIG 2B may be preferable in applications where it is desirable to
minimize the size of the container 101 when stored in the flat configuration.
[0049] When the container 101 is ready for use, it may be transitioned to
a three-dimensional open configuration, an example of which is depicted in FIG
3. If the container 101 is in the first flat configuration (i.e. side panels
110,
115 folded outwards as in Figure 2A), this may be achieved by applying an
inward force at fold lines 111, 116, which in turn causes the container 101 to
open into the three-dimensional configuration. If the container is in the
second
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flat configuration (i.e. side panels 110, 115 folded inwards as in Figure 2B),
this may be achieved by applying an outward force at the end panel 105 and
the bottom panel formed by bottom flaps 120, 130. In either case, the force
applied to transition the container may be applied manually or by automated
means.
[0050] After filling the container 101, the lid 140 is secured to the
flanges
113, 118, 131 as described above. Closure of the lid 140 thereby provides
structural stability to the container 101, so as to resist transition back to
a flat
configuration. In embodiments where a sealing closure is used, closure of the
lid 140 may also provide a barrier against the escape of small particles,
liquids,
or gasses from the container 101.
[0051] Blank 100 may be fabricated by known techniques such as cutting,
stamping or the like from a roll or sheet of material. Various suitable
materials
may be used to form the blank 100, depending on the application. For
example, paperboard materials such as heavy papers, card stock, or corrugated
cardboard may be used. Other suitable materials include plastics, such as
polyethylene terephthalate (PET), high density polyethylene (HDPE), polyvinyl
chloride (PVC), Low density polyethylene (LDPE), polypropylene (PP),
polystyrene (PS), or a combination thereof.
[0052] The manufacturing process may begin by cutting or stamping the
chosen material into the outline of a blank 100 in accordance with the present
invention. In the blank 100 depicted in FIG 1, this process is simplified by
the
fact that no internal cuts are required in the blank 100 unless a window 150
is
provided. The generally triangular shape of the blank 100 also aids in
arranging a series of blanks 100 along a single sheet of starting material, so
as
to minimize the amount of waste left behind after cutting. If the blank 100
includes a window 150, it may be cut out at this time and a transparent window
material, such as a plastic film may be applied either immediately after
cutting
or as the final step in assembly of the blank 100. Fold lines 106, 107, 108,
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109, 111, 112, 116 and 117 are then imparted onto the cut material to create
the blank 100, often by pre-scoring or perforating the material.
[0053] Assembly of the container 101 from the blank 100 is achieved by
folding the blank 100 along fold lines 106, 107, 108, 109, 111, 112, 116 and
117 and securing the bottom flaps 120 and 130 to one another (and if present,
to the central flap 125) in the manner described above. If present, flanges
113, 118, 131 may also be folded outwards in preparation for securing the lid
140. Inward folding of flanges 113, 118 and 131 may also be used,
depending on the application.
[0054] In general, folds are either of a 'hill type' or 'valley type'. The
particular folds applied to each fold line 106, 107, 108, 109, 111, 112, 116
and 117 when assembling the container 101 depend on the desired
configuration of the container 101 and would be apparent to the person of
skill
in view of the present specification.
[0055] For example, in the preferred embodiment depicted in FIG 2A, fold
lines 106, 107, 108, 109, 111, 112, 116 and 117 are all valley folds, which
may simplify the assembly process for this blank 100. In contrast, the
embodiment depicted in FIG 2B uses hill folds for the apical fold lines 111
and
116, so as to permit the side panels 110, 115 to fold inwards when in the
second flat configuration. If flanges 113, 118 and 131 are to face outward,
they are subjected to hill folds. If flanges 113, 118 and 131 art to face
inward,
they are subjected to valley folds.
[0056] In applications involving high throughput assembly of the container
101, it may be preferable to use automated means for folding the blank 100
and securing the bottom flaps 120, 130 (and if present, to the central flap
125). Suitable equipment for the application in question would be apparent to
the person of skill in view of the present specification.
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[0057] Figures 4 and 5 depict alternative embodiments of the invention.
FIGS 4A-4D show blanks 200 according to the invention in which the lid 240
has one or more windows 250 therein. As seen in Figures 4A through 4D,
windows 250 may be consist of an elongated rectangle, a trapezoid, an oval or
a pair of semicircles. It will be evident that many other window
configurations
may be provided. Windows 150, 250, 350 are covered with a transparent
material such as cellophane or plastic film.
[0058] The blanks 200 are depicted in FIGS 4A to 4D using similar ,
reference numerals in the '200' series to denote structures which serve
analogous functions to those described above for blank 100.
[0059] Briefly, each blank 200 comprises an end panel 205 hinged to side
panels 210, 215 at fold lines 206 and 207. A lid 240 and central flap 225 are
also hinged to the end panel 205 at fold lines 208 and 209. The lid 240 may
include a window 250. Apical fold lines 211, 216 which begin at an apex 221
and end at a hypotenuse 229 divide the side panels 210, 215 into subpanels
210a/210b and 215a/215b. Bottom flaps 220, 230 are hinged to the side
panels 210, 215 at fold lines 217 and 212, respectively. In this blank 200,
flanges 213, 218, 231a, 231b are provided to facilitate closure of the lid
240.
[0060] Unlike the blank 100 shown in FIG 1, the bottom flaps 220, 230 of
the blank 200 in FIGS 4A-4D are of essentially equal size. As such, there is
no
preferred ordering or sequence for layering the respective flaps 220 and 230
during assembly of the container, as neither flap is capable of providing a
continuous interior surface.
[0061] A further feature shown in the blank 200 of FIGS 4A-4D is that
flaps 220 and 230 are each provided with a flange 231b and 231a respectively
extending laterally therefrom, so as to permit a continuous flange structure
to
be formed when the container is assembled. In the blank 200 in FIGS 4A-4D,
flanges 231a and 231b do not fully extend across the full length of the side
edge of their respective flap 220, 230. As a result, the outer corners of
flaps
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220 and 230 have a notch 233. When the container is assembled, notches
233 are aligned and overlie each other to allow the 231a/231b to abut one
another when the bottom flaps 220, 230 are secured, so as to form an
essentially continuous shelf-like flange extending along the bottom panel of
the
container assembled from the blank 200.
[0062] Figures 5A through 5D show further embodiments wherein the
width of the container is narrower than the preceding embodiments. Again,
similar reference numerals in the '300' series are used to denote analogous
features.
[0063] Briefly, each blank 300 comprises an end panel 305 hinged to side
panels 310, 315 at fold lines 306 and 307. A lid 340 and central flap 325 are
also hinged to the end panel 305 at fold lines 308 and 309. The lid 340 may
include a window 350. Apical fold lines 311, 316 which begin at an apex 321
and end at a hypotenuse 329 divide the side panels 310, 315 into subpanels
310a/310b and 315a/315b. Bottom flaps 320, 330 are hinged to the side
panels 310, 315 at fold lines 317 and 312, respectively. In this blank 300,
flanges 313, 318, 331a, 331b are provided to facilitate closure of the lid
340.
Notches 333 are provided at the outer corners of the bottom flaps 320, 330,
which can be aligned to provide a continuous shelf like flange extending along
the bottom panel of the container assembled from the blank 300.
[0064] The container formed from a blank 100, 200, 300 according to the
present invention can have various dimensions. For example, the blanks 100
and 200 shown in FIGS 1-4D are designed to provide a container suitable for
two triangular halves of a sandwich, whereas the blanks 300 of FIGS 5A-5D are
designed to hold a smaller article, such as one half of a sandwich. In blank
300,
this is accomplished by reducing the width of the end panel 305, lid 340,
window 350, central flap 325, and bottom flaps 320,330. The blanks 300 in
FIGS 5A-5D also include windows 350 having a variety of configurations similar
to those of Figures 4A through 4D.
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[0065] It will be understood that in the blank 300 shown in FIGS 5A-5D
may be too narrow to permit the second flat configuration shown in FIG 2B,
since there may be insufficient room to fold the side panels 310 and 315
inwards. This occurs where the area of subpanel 315a or 310a cannot be
circumscribed within the area of end panel 305 when the blank 300 is folded
along fold lines 306 and 307. In such situations, the first flat configuration
shown in FIG 2A would be used.
[0066] The embodiments of the present application described above are
intended to be examples only. Those of skill in the art may effect
alterations,
modifications and variations to the particular embodiments without departing
from the intended scope of the present application. In particular, features
from
one or more of the above-described embodiments may be selected to create
alternate embodiments comprised of a subcombination of features which may
not be explicitly described above. In addition, features from one or more of
the
above-described embodiments may be selected and combined to create
alternate embodiments comprised of a combination of features which may not
be explicitly described above. Features suitable for such combinations and
subcombinations would be readily apparent to persons skilled in the art upon
review of the present application as a whole. The subject matter described
herein and in the recited claims intends to cover and embrace all suitable
changes in technology.