U.S. patent application number 11/379343 was filed with the patent office on 2006-10-19 for carton with composite wall and expansion panels.
Invention is credited to John M. JR. Holley.
Application Number | 20060231600 11/379343 |
Document ID | / |
Family ID | 37114212 |
Filed Date | 2006-10-19 |
United States Patent
Application |
20060231600 |
Kind Code |
A1 |
Holley; John M. JR. |
October 19, 2006 |
CARTON WITH COMPOSITE WALL AND EXPANSION PANELS
Abstract
An expansion panel assembly (200a) for use with a tubular carton
(C). The expansion panel assembly (200a) includes means for
cooperative relief, a slidable section (152a) and fixed sections
(150a). Means for cooperative relief includes relief apertures
(140a), expansion cuts (144a), and expansion hinges (146a). The
relief apertures (140a) each span a portion of inner top panel
(110) and expansion panel (136a). Expansion cuts (144a) define
expansion hinges (146a), as well as expansion flap fixed sections
(150a) and expansion panel slidable section (152a).
Inventors: |
Holley; John M. JR.;
(Lawrenceville, GA) |
Correspondence
Address: |
PARKS KNOWLTON LLC
1117 PERIMETER CENTER WEST
SUITE E402
ATLANTA
GA
30338
US
|
Family ID: |
37114212 |
Appl. No.: |
11/379343 |
Filed: |
April 19, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60672933 |
Apr 19, 2005 |
|
|
|
Current U.S.
Class: |
229/103.2 |
Current CPC
Class: |
B65D 2571/00574
20130101; B65D 71/36 20130101; B65D 2571/00728 20130101; B65D
2571/00469 20130101; B65D 2571/00549 20130101; B65D 2571/00543
20130101; B65D 2571/00839 20130101; B65D 2571/00141 20130101; B65D
2571/0066 20130101 |
Class at
Publication: |
229/103.2 |
International
Class: |
B65D 5/00 20060101
B65D005/00 |
Claims
1. A carton for enclosing articles, comprising: a composite wall,
comprising: an outer panel; and an inner panel secured to the outer
panel such that at least a portion of the outside surface of the
inner panel is fixedly secured to at least a portion of the inside
surface of the outer panel; and an end wall closure, comprising: a
composite end wall panel hingedly connected to the composite wall,
comprising: an outer end wall panel hingedly connected to the outer
panel; and an expansion panel hingedly connected to the inner
panel, the expansion panel comprising: at least one fixed section,
its outside surface being fixedly secured to the inside surface of
the outer end wall panel; and at least one slidable section, its
outside surface being disposed against the inside surface of the
outer end wall panel in a face-contacting arrangement, and its
outside surface being slidable from a neutral position to a stress
relieving position with respect to the inside surface of the outer
end wall panel.
2. The carton of claim 1, wherein the end wall panel is hingedly
connected to the outer panel along a first fold line and the
expansion panel is hingedly connected to the inner panel along a
second fold line, the first and second fold lines being
substantially coincident as to form a composite hinge.
3. The carton of claim 2, wherein the composite end wall panel is
folded inwardly toward the composite wall and along the composite
hinge.
4. The carton of claim 2, further comprising means for
cooperatively relieving stress along the composite hinge.
5. The carton of claim 4, wherein means for cooperative relief
comprises an expansion hinge flexibly connecting the fixed section
to the slidable section, the expansion hinge controlling the extent
to which the slidable portion slides from the neutral position to
the stress relieving position.
6. The carton of claim 5, wherein means for cooperative relief
further comprises an expansion cut for at least partially detaching
the slidable section from the fixed section.
7. The carton of claim 4, wherein means for cooperative relief
comprises at least one relief fold cut parallel and adjacent to the
composite hinge.
8. The carton of claim 7, wherein the relief fold cut is formed in
the fixed section.
9. The carton of claim 4, wherein means for cooperative relief
comprises at least one relief aperture disposed through a portion
of the expansion panel and of the inner panel.
10. The carton of claim 4, wherein means for cooperative relief
comprises at least one relief aperture disposed through a portion
of the slidable section and of the inner panel.
11. The carton of claim 1, wherein the composite wall further
comprises a handle.
12. A carton for enclosing articles, comprising: a composite top
wall, comprising: an outer top panel; an inner top panel secured to
the outer top panel such that the outside surface of the inner top
panel is fixedly secured to the inside surface of the outer top
panel; and a handle comprising at least one handle aperture
disposed through at least one of the inner and the outer top
panels; a bottom wall opposite the composite top wall; an end wall
closure, comprising: a lower end wall panel hingedly connected to
the bottom wall; and a composite upper end wall panel hingedly
connected to the composite top wall and secured to the lower end
wall panel in an overlapping configuration, the composite upper end
wall comprising: an upper end wall panel hingedly connected to the
outer top panel; and an expansion panel hingedly connected to the
inner top panel, the expansion panel comprising: a first fixed
section, its outside surface being fixedly secured to the inside
surface of the upper end wall panel; a slideable section adjacent
to the first fixed section, its outside surface being disposed
against the inside surface of the upper end wall panel in a
face-contacting arrangement, and its outside surface being slidable
from a neutral position to a stress relieving position with respect
to the inside surface of the outer end wall panel; a second fixed
section adjacent to the slidable section, its outside surface being
fixedly secured to the inside surface of the upper end wall panel;
a first expansion cut partially detaching the slidable section from
the first fixed section; a second expansion cut partially detaching
the slidable section from the second fixed section; a first
expansion hinge flexibly connecting the slideable section to the
first fixed section, comprising a slit extending from the toward
expansion cut toward the second fixed section; and a second
expansion hinge flexibly connecting the slideable section to the
second fixed section, comprising a slit extending from the second
expansion cut toward the first fixed section.
13. A blank for forming a carton for enclosing articles,
comprising: an elongate transverse section comprising: an outer
composite wall panel; a first side panel hingedly connected to the
outer composite wall panel; a bottom panel hingedly connected to
the first side panel; a second side panel hingedly connected to the
bottom panel; an inner composite wall panel hingedly connected to
the second side panel; and an end wall panel hingedly connected to
the outer composite wall panel; and an expansion panel hingedly
connected to the inner composite wall panel, the expansion panel
comprising: a first fixed section defined in part by the hinged
connection between the expansion panel and inner composite wall
panel; a second fixed section defined in part by the hinged
connection between the expansion panel and inner composite wall
panel; at least one slidable section adjacently disposed between
the first fixed section and the second fixed section; and means for
cooperative relief.
14. The blank of claim 13, wherein the means for cooperative relief
comprises: a first expansion cut partially detaching the slidable
section from the first fixed section; a second expansion cut
partially detaching the slidable section from the second fixed
section; a first expansion hinge flexibly connecting the slideable
section to the first fixed section, comprising a slit extending
from the toward expansion cut toward the second fixed section; and
a second expansion hinge flexibly connecting the slideable section
to the second fixed section, comprising a slit extending from the
second expansion cut toward the first fixed section.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Application No.
60/672,933, filed Apr. 19, 2005, the entirety of which is
incorporated herein by reference.
TECHNICAL FIELD
[0002] This invention relates generally to packaging, and in
particular, to a carton having a composite wall with expansion
panels.
BACKGROUND OF THE INVENTION
[0003] Many different types of paperboard cartons for enclosing
products such as beverage cans and bottles are well known in the
industry. When the product load is relatively heavy, carton
manufacturers often reinforce all or part of the carton, such as by
constructing one or more carton walls, end flaps, or end wall
panels of high-bulk sheet material having a relatively high
caliper, or by doubling-over the carton material to increase the
thickness and durability of the resultant two-ply structure. A
two-ply, hereinafter referred to as a composite or laminated
structure, can be stronger than a doubly thick structure,
particularly because of the adhesive layer that holds the plies
together. Furthermore, a composite configuration is better able to
resist scarring and deformation of the art side of the carton that
can be caused by sharp edges of the products abrading or puncturing
the walls of the carton. For instance, glass bottles are commonly
sealed with metal crown caps having crimped annular edges that tend
to scuff against the inside surface of the carton, which can cause
visible imperfections to be evident from the outside of the carton.
Consumers typically avoid purchasing products enclosed in packaging
that is apparently damaged, often assuming that the contents are
damaged as well, or generally perceiving the product to be of less
value. Composite structures are useful because the inner layer of a
composite carton composite carton wall tends to bear the brunt of
the resulting deformation, sparing the outside surface of the outer
layer.
[0004] Despite the inherent advantages of composite carton walls,
there are several disadvantages to prior art efforts. In some
instances, completely composite cartons have been manufactured with
all walls having multiple laminated plies. Obviously, the cost of
such cartons is unnecessarily increased by the excess sheet
material, particularly as only certain carton walls need additional
strength with respect to other carton walls. Furthermore, it can be
difficult to fold a composite structure composed of two layers of
sheet material with adhesive between the two plies, even if fold
lines are scored into each of the layers. The adhesive resists the
tendency of one layer to slide with respect to the other when the
composite structure is flexed or bent, thereby generating a shear
force along the layers of the composite structure. The opposing
forces cause undesired stresses on the fold and on the adjacent
panels, possibly precluding a clean fold, overcoming the holding
power of glue applied to secure the composite panel in folded
position, or otherwise impeding the operation of automatic
packaging machinery.
[0005] What is needed is a carton configuration that selectively
provides the added strength and thickness of a composite structure,
efficiently utilizes sheet material, and provides composite
portions that are easily manipulable into the desired
configuration.
SUMMARY OF THE INVENTION
[0006] The various embodiments of the present invention address the
identified need by providing a carton with a composite wall that is
secured to adjacent walls by expansion means comprising one or more
expansion panels. The expansion panels are connected to the
composite wall and secured to an adjacent wall so as to prevent the
layers of the composite wall from delaminating.
[0007] Advantageously, the expansion panel of the present invention
includes at least one fixed section that is secured to the adjacent
wall, and at least one slidable section differentiated by an
expansion cut or an expansion hinge that permits the expansion
panel to slide with respect to the adjacent wall to which it is
attached. In certain embodiments, the expansion panel also includes
relief apertures that are cut out of the expansion panel to
facilitate a clean fold.
[0008] More specifically, the aspects and features of the invention
are described with respect to an exemplary carton formed from a
blank cut from a unitary piece of sheet material, such as
paperboard. According to the invention, the blank includes an
elongate transverse section comprising several panels that can be
configured and secured to form several carton walls, including at
least one composite wall consisting of at least an outer wall panel
and an inner wall panel. An end wall panel secured to an expansion
panel creates a foldable composite end wall panel that reinforces
the lamination of the composite wall as part of an end wall closure
structure.
[0009] The exemplary blank includes an outer top panel hingedly
connected to a first side panel. The first side panel is hingedly
connected to a bottom panel, which is hingedly connected to a
second side panel. The second side panel is hingedly connected to
an inner top panel. At each end, the inner top panel is hingedly
connected to respective expansion panels. At each end, the outer
top panel and the bottom panel are hingedly connected to respective
upper end wall panels and lower end wall panels. The carton is
erected by securing the outer surface of the inner top panel to the
inside surface of the outer top panel, thereby creating a composite
top wall. In this manner, the first side panel becomes a first side
wall, the bottom panel becomes a bottom wall, and the second side
panel becomes a second side wall. The composite top panel may
include racetrack or other handle apertures disposed through both
the inner and the outer top panels to facilitate carrying the
carton. The outside surface of the fixed section of each expansion
panel is secured to the inside surface of the upper end wall panel,
thereby creating a composite upper end wall panel that is hingedly
connected to the composite top wall along a composite hinge. The
composite end wall panel and the lower end wall panel are folded
toward one another and secured together in overlapping fashion to
create an end wall closure, which may also include end flaps
connected to both ends of each side wall, the outside surface of
each end flap being secured to the inside surfaces of the composite
end wall panel and the lower end wall panel.
[0010] According to one aspect of the invention, the configuration
of the exemplary expansion panel facilitates folding the composite
end wall panel along the hinged connection between the composite
end wall panel and the composite top wall. The expansion panel
extends from the hinged connection with the inner top panel, and
has dimensions that yield at least one fixed section that is
sufficient to reinforce lamination of the composite top wall. The
fixed section is adjacent to at least one slidable section that is
free from the upper end wall panel. An expansion hinge connects the
fixed section to the slidable section, and permits the outside
surface of the slidable section to slide against the inner surface
of the upper end wall panel. Thus, undesired shear stress between
the respective surfaces is avoided, while the advantages of the
two-ply structure are maintained. More specifically, when the
composite end wall panel and the composite top wall lie in the same
plane, the slidable section is at a neutral first position with
respect to the upper end wall panel and the fixed section. When the
composite end wall panel is folded about the hinged connection with
the composite top wall panel, the slidable section slides with
respect to the upper end wall panel and the fixed section, to a
stress relieving second position.
[0011] To reinforce the lamination of the composite top wall, the
outside surface of each fixed section of the expansion panel is
fixedly secured to the inside surface of the upper end wall panel,
thereby creating the composite end wall panel. To facilitate
folding the composite end wall panel, a slidable section is
adjacent to each fixed section, its outside surface being disposed
against the inside surface of the upper end wall panel in a
face-contacting arrangement, and its outside surface being slidable
from a neutral position to a stress relieving position with respect
to the inside surface of the outer end wall panel. The slidable
section also provides continuity of the thickness of the composite
end wall panel to protect the outside surface from damage caused by
the articles contained within the carton.
[0012] In certain embodiments, the expansion panel includes a
single slidable section having a fixed section on each side. The
slidable section is made slidable by a means for cooperatively
relieving stress along the composite hinge. The means for
cooperative relief includes an expansion cut or other severance
means by which the slidable section is partially detached and
defined with respect to each respective fixed section. Each
expansion cut extends away from the hinged connection between the
expansion panel and the inner top panel and turns toward a side
edge of the expansion panel, defining an expansion hinge between
the severance line and the end edge of the expansion panel. The
expansion hinge allows and controls the transition from the neutral
position to the stress relieving position. In still other
embodiments, a two-ply structure is provided at those sections
adjacent to the metal crown caps, or similar sharp elements, to
reduce damage to the carton or articles.
[0013] In certain other embodiments, the expansion panel includes a
single fixed section having a slidable section on each side. The
fixed section is similarly partially detached and defined with
respect to each slidable section by means for cooperative relief,
preferably including respective expansion cuts, each of which
extends away from the hinged connection between the expansion panel
and the inner top panel and turns toward the center of the
expansion panel, defining an expansion hinge between the severance
line and the end edge of the expansion panel. In still other
embodiments, the expansion panel includes a single fixed section
and a single slidable section. The fixed section is defined with
respect to the slidable section by an expansion cut or other
severance means which extends away from the hinged connection
between the expansion panel and the inner top panel and turns
toward the center of the expansion panel, defining an expansion
hinge between the expansion cut and the end edge of the expansion
panel. In still other embodiments, the expansion panel includes one
or more fixed sections and one or more slidable sections wherein
the slidable sections are not hingedly attached to the fixed
sections but to the respective adjacent top, bottom, or side
panel.
[0014] According to another aspect, means are provided for
relieving stress at the hinged connection between the composite end
wall panel and the composite top wall. In certain embodiments, the
stress relieving means include relief apertures disposed at or near
the hinged connection between the composite end wall panel and the
composite top wall. The location and extent of the stress relieving
means is tailored to remove or liberate sheet material disposed at
or near the hinged connection.
[0015] In certain embodiments, at least one relief aperture is
disposed across at least a portion of the hinged connection, and is
formed by creating an aperture that removes a portion of the
expansion panel and of the inner top panel. The stress relieving
means reduces bunching caused by congestion of sheet material at
the fold, encouraging a cleanly creased fold that has less of a
tendency to resist remaining in a folded condition.
[0016] It is contemplated that a carton incorporating the various
aspects of the invention may include more than one composite wall.
For example to strengthen the bottom wall of the carton, as well as
the top, the blank may be formed from two pieces of sheet material.
The first piece of sheet material includes the outer top panel, the
first side wall, and an inner bottom panel having an expansion
panel as described above. The second piece of sheet material
includes the earlier described bottom panel, the second side panel,
and the inner top panel having an expansion panel as described
above. To begin erecting this exemplary carton, the outside
surfaces of the inner bottom panel and the expansion panel are
secured to the inside surfaces of the earlier described bottom
panel and the lower end flap, respectively. In this fashion, a
composite bottom wall and a composite lower end wall panel is
created. Then, the carton is erected as described above with
respect to the carton of the previous embodiments.
[0017] The foregoing has broadly outlined some of the aspects and
features of the present invention, which should be construed to be
merely illustrative of various potential applications of the
invention. Other beneficial results can be obtained by combining
portions of the disclosed information and the disclosed
embodiments, such as by altering the orientation of the respective
composite and single ply walls. Accordingly, other aspects and a
more comprehensive understanding of the invention may be obtained
by referring to the detailed description of the exemplary
embodiments taken in conjunction with the accompanying drawings, in
addition to the scope of the invention defined by the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 illustrates a plan view of one embodiment of a blank
for forming a carton, according to the present invention.
[0019] FIG. 2 is a perspective view of a partially erected carton
formed from the blank of FIG. 1 in a tubular condition, according
to the present invention.
[0020] FIG. 3 is a partial interior perspective view of a fully
constructed expansion panel assembly, according to the present
invention.
[0021] FIG. 4 is a partial interior perspective view of a fully
folded expansion panel assembly, according to the present
invention.
[0022] FIG. 5 is a partial interior perspective view of an
alternative embodiment of a fully constructed expansion panel
assembly, according to the present invention.
[0023] FIG. 6 is a partial interior perspective view of an
alternative embodiment of a fully constructed expansion panel
assembly, according to the present invention.
DETAILED DESCRIPTION
[0024] As required, detailed embodiments of the present invention
are disclosed herein. It must be understood that the disclosed
embodiments are merely exemplary of the invention that may be
embodied in various and alternative forms, and combinations
thereof. As used herein, the word "exemplary" is used expansively
to refer to embodiments that serve as illustrations, specimens,
models, or patterns. The figures are not necessarily to scale and
some features may be exaggerated or minimized to show details of
particular components. In other instances, well-known components,
systems, materials, or methods have not been described in detail in
order to avoid obscuring the present invention. Therefore, specific
structural and functional details disclosed herein are not to be
interpreted as limiting, but merely as a basis for the claims and
as a representative basis for teaching one skilled in the art to
variously employ the present invention.
[0025] Referring now to the drawings in which like numerals
indicate like elements throughout the several views, the drawings
illustrate exemplary embodiments of an expansion panel assembly
200, best shown in FIG. 3, for use with a tubular carton C, best
shown in FIG. 2. In the embodiments illustrated and described
herein, the tubular carton C dispenses articles such as, but not
limited to, beverage bottles. Generally described, the tubular
carton C is formed from a foldable sheet material such as
paperboard, corrugated board, plastic, or the like, and composites
thereof.
[0026] With regard to the exemplary embodiment shown in FIG. 1, the
tubular carton C is formed from a paperboard blank 100. The
illustrated blank 100 includes five primary panels for forming the
carton C. The panels of the blank 100 include an outer top panel
102, a first side panel 104, a bottom panel 106, a second side
panel 108, and an inner top panel 110. The panels 102, 104, 106,
108, and 110 of the blank 100 are hingedly connected to one
another. The outer top panel 102 is hingedly connected to the first
side panel 104 by fold line 112. The first side panel 104 is
hingedly connected to the bottom panel 106 by fold line 114. The
bottom panel 106 is hingedly connected to the second side panel 108
by fold line 116. The second side panel 108 is hingedly connected
to the inner top panel 110 by fold line 118. In the illustrated
embodiment, a unitary blank 100 is used to form a single carton C,
although in alternative embodiments two or more blanks may be
employed to provide a carton C with the illustrated expansion panel
assembly 200.
[0027] Each of the panels 102, 104, 106, 108, and 110 includes
opposing end flaps defined in part by transverse fold lines
disposed along opposite transverse edges of the blank 100. When the
carton C is erected, the end flaps cooperate to form an end closure
structure that includes an expansion panel assembly 200. In the
embodiments illustrated, each end closure structure is sufficiently
identical that like references have been used, with "a" or "b"
affixed to distinguish the components of one end of the carton C
from the other. Accordingly, the teaching will continue with
reference only to those sections of the illustrated embodiments
with the designation "a". The outer top panel 102 is hingedly
connected to end flap 120a along fold line 122a. First side panel
104 is hingedly connected to end flap 124a along fold line 126a.
Bottom panel 106 is hingedly connected to end flap 128a along fold
line 130a. Second side panel 108 is hingedly connected to end flap
132a along fold line 134a. Inner top panel 110 is hingedly
connected to expansion flap 136a along fold line 138a.
[0028] The expansion panel 136a further comprises several elements.
Relief apertures 140a each span a portion of inner top panel 110
and expansion panel 136a. Expansion cuts 144a define expansion
hinges 146a, as well as expansion flap fixed sections 150a and
expansion panel slidable section 152a. Expansion flap fixed and
slidable sections are best described with regard to FIGS. 2 and
3.
[0029] With continued reference to FIG. 1, the blank 100 includes
frangible severance line segments 160, 162, and 164, which, when
the carton C is erected, form frangible severance lines 170, best
shown in FIG. 2. It is contemplated that a frangible severance line
includes, but is not limited to, perforations, a line of
perforations, a line of short slits, a line of half cuts, a single
half cut, any combination of slits, score lines, and half cuts, or
the equivalent. In the embodiment illustrated, the severance lines
170 cooperate to provide removable sections T, which provide access
to the articles, as understood by those skilled in the art.
[0030] The illustrated blank 100 further comprises a suitable known
handle, formed from handle apertures 172, that allows the user to
carry the carton C. The illustrated handle is often referred to as
a race track handle. In a carton C with a race track handle, one
carton C wall is provided with a first hand aperture at a position
spaced from a second hand aperture such that the first and second
apertures define a handle strip therebetween. To distribute stress
away from the handle strip area, reinforcing fold lines 174 may be
used according to the invention. Such fold lines may be provided to
extend from each aperture 172 toward an adjacent corner of the wall
formed by the top panel 102 of the carton C. A set of fold lines
may emerge from each aperture 172 and diverge from each other as
they approach the adjacent corner. Alternatively, a greater or
lesser number of fold lines may emerge from each aperture 172.
[0031] With regard to the assembling and erecting of the
illustrated blank 100 to form a carton C having an expansion panel
assembly 200, reference will be made herein to the inside or inner
surface and the outside or outside surface of the various panels.
The inside or inner surface is that which is visible in the various
figures while the outside or outer surface not visible in the
various figures. Stated another way, upon forming a tubular carton
C from the blank 100, the inside or inner surface of each panel
typically face inwardly while the outside or outer surface of each
panel are those sides typically face outwardly.
[0032] With reference now to FIG. 2, the carton C is arranged in a
tubular condition as the outer surface of inner top panel 110 is
matingly secured to the inner surface of outer top panel 102 to
form the composite top wall 102/110 of an open ended tubular carton
C. In the tubular condition, the composite top wall 102/110 is
coplanar with the respective upper end wall flap 120a and expansion
panel 136a. Stated differently, the end wall flap 120a and
expansion flap 136a are shown prior to folding. In the illustrated
embodiments, the panels, flaps, and their respective elements are
aligned or placed immediately adjacent to each other such that they
matingly cooperate. In other embodiments, corresponding elements do
not have to be perfectly aligned as being merely proximate permits
an enabling embodiment. In still other embodiments, elements of the
inner flap may not be secured to the outer flap, or visa-versa. The
panel and flap connection may be made by use of chemical or
mechanical adhesives or other means for securing including locking
tabs, as understood by those skilled in the art.
[0033] The inner top panel 110 is aligned with the outer top panel
102 such that the respective handle apertures 172 matingly
cooperate, and such that the respective severance line segments 160
and 162 matingly cooperate. Further, expansion flap 136a is aligned
and secured, in the manner described below with regard to the
various embodiments, to upper end wall panel 120a, such that fold
line 138a is aligned with fold lines 122a. In addition, each relief
aperture 140a is disposed astride fold line 122a. Further, it
should be clear that what is described herein with regard to the
expansion panel assembly 200a located at one end of the carton C
applies equally to the expansion panel assembly 200b located at the
other end of the carton C, in those embodiments wherein the carton
C has expansion flap assemblies at both ends.
[0034] As explained herein, one advantage of the present invention
is to provide a carton C of increased strength and carrying
capacity. One embodiment of a carton C of increased strength and
carrying capacity comprises a two-ply top or bottom wall assembly
and a two-ply end wall assembly. While a standard two-ply end wall
assembly provides advantages, including increased strength and
damage protection, the folding of such assemblies and the erecting
of cartons C with such assemblies present certain challenges. These
challenges include increased resistance to the folding of the end
wall panels and the subsequent buckling of adjacent panels; however
these challenges are overcome with the embodiments taught and
claimed herein.
[0035] With regard to the two-ply end wall embodiments illustrated
in FIGS. 2-4 inclusive, expansion flap 136a is secured to end wall
flap 120a with adhesives or glues as well known to those skilled in
the art. However, other means for securing may be used. As stated
above, expansion flap 136a comprises at least one fixed section
150a and at least one slidable section 152a. Fixed panel section(s)
150a are secured to end wall flap 120a in face-contacting
relationship while slidable section 152a is not.
[0036] After the articles to be placed into the carton C are
grouped and loaded through either or both of the open ends of the
carton C, the open ends are to be closed and sealed. With reference
to FIG. 3, a partial sectional view of the interior of an expansion
panel assembly 200a is shown before that assembly is folded to form
a closed end wall structure. A folding sequence to close the open
ends of carton C includes folding the end flaps 124a, 132a inwardly
and positioning the end flaps 124a, 132a so that the outside of
these flaps may be connected to the inside of the expansion flap
136a. In order to more clearly teach the movement of the expansion
panel assembly 200, the end flaps 124a, 132a are shown to be torn
away or are otherwise partially shown when in the fully folded
position of FIG. 4. In other embodiments, the inside of end flaps
124a, 132a may be connected to the outside of the end wall flap
120a.
[0037] As understood by those skilled in the art, folding or
otherwise bending a panel or flap causes the fibers of one surface
to be put in compression while the fibers of the opposite surface
are put in tension. For example, and with a momentary reference to
FIG. 1, folding end wall flap 120a inwardly along fold line 122a so
that the inside of that flap faces the inside of top panel 102, the
fibers along the inside surface are in compression while the fibers
along the outside surface are in tension. The effect of these
compression and tension stresses is typically visible, particularly
along the bend or fold line, in that the outside surface may appear
stretched while the inside surface may appear bunched.
[0038] As further understood by those skilled in the art, when two
panels are secured along their surfaces and then folded as a unit,
the stresses along the joined surfaces act to create a shear force
along the laminate. More specifically, in folding a two-ply panel
that is not perfectly laminated, the upper surface of the lower
panel is put into tension while the lower surface of the upper
panel is put into compression. Folding an increased number of
layers of material increases the shear stresses in the material and
affects the performance characteristics of the material. For
example, the increased thickness of a two-ply panel increases the
folding resistance of the panel and, in folding such a panel, the
shear stresses that are created may cause buckling.
[0039] To significantly reduce or eliminate the shear stresses and
undesired performance characteristics introduced by folding a
two-ply panel, a means for relief is provided in the expansion
panel 136a. Means for cooperative relief includes a relief aperture
140a, or an expansion cut 144a, or an expansion hinge 146a. The
configurations of the aperture 140a, expansion cut 144a, or the
expansion hinge 146a, separately or together, are not limited to
the illustrated cuts and hinges but may be of any shape desired
that allows the slidable section 152a to move with respect to the
fixed section 150a. Additional means for cooperative relief are
described below.
[0040] Returning to FIG. 3, inwardly folding end wall panel 120a
together with the connected expansion panel 136a will create the
shear stress and related undesired performance characteristics
described above. With regard to the means for relief provided in
the expansion panel, the undesired performance characteristics and
shear stresses are greatly reduced, if not eliminated, along the
sections of fold line 122a where the relief apertures 140a are
positioned. The relief apertures 140a are provided to prevent the
overcrowding of material and may be of any shape. In some
embodiments, the relief apertures are configured to absorb stresses
by changing shape when folded.
[0041] The shear and compressive stresses that would otherwise
remain along fold line 122a in a two-ply panel are reduced through
the means for cooperative relief. As shown by the arrows labeled F
that represent the shifting forces as well as the direction of
movement for the slidable section 152a, the slidable section 152a
is moved downwardly, about hinges 146a, from a first position
P.sub.1 (best shown in FIG. 3) to a second position P.sub.2 (shown
in FIGS. 3 and 4). The displacement of the slidable section 152a
may be represented by the extent to which the hinges 146a have
opened as well as by the extent to which the slidable portion edge
180 has shifted with regard to the adjacent fixed section edge
181.
[0042] Referring to FIG. 4, when the expansion panel assembly 200a
has been folded as far as the carton C design requires and the
slidable section has reached the second position P.sub.2, the
assembly 200a may be attached to the end flaps 124a, 132a.
Attaching the folded assembly to the end flaps may fix the slidable
section at the second position P.sub.2. FIG. 4 illustrates a
portion of the interior of an end wall structure of the carton C
including the expansion flap assembly 200a, which is folded and
attached to end flaps 124a, 132a. To facilitate clarity in
teaching, FIG. 4 does not show the entirety the end flaps 124a,
132a shown in the blank 100, nor does it show the end wall flap
128a. Nevertheless, with regard to methods of folding and closing
of an end wall structure, and as well understood by those skilled
in the art, one method includes inwardly folding the end flaps
124a, 132a, inwardly folding and connecting expansion flap assembly
200a to the end flaps, and inwardly folding the bottom end flap
128a to the top end flap 120a, preferably in an overlapping
arrangement. Other methods include alternating the sequence of
folding and connecting the various flaps, as desired.
[0043] Expansion panel assemblies of various and alternative
embodiments are considered, taught, and claimed herein. Two
illustrated alternative embodiments are shown in FIGS. 5 and 6. To
significantly reduce or eliminate the shear stress and undesired
performance characteristics introduced by folding a two-ply panel,
expansion panel assembly 300 includes a fixed section 350a and
slidable sections 352a. The expansion panel assembly 300 further
includes at least one means for cooperative relief. Means for
cooperative relief includes one or more relief apertures 340a, one
or more expansion cuts 344a, and one or more expansion hinges
346a.
[0044] Similar to the expansion panel assembly 200a shown in FIG.
3, the expansion flap assembly 300 shown in FIG. 5 is in the
pre-folded first position P.sub.1. As the expansion flap assembly
300 is folded, the stresses that would otherwise remain along fold
line 320--the area of concentration--are reduced or shifted through
the means for cooperative relief. The arrows labeled F represent
the direction of shifting forces on the slidable sections 352a
wherein the shifting forces are applied as the expansion panel
assembly 300 is folded along fold lines 322a, 338a. As the shifting
forces are applied, the slidable sections 352a are moved downwardly
about hinges 312 from a first position P.sub.1 to a second position
P.sub.2 (not shown). The second position P.sub.2 resembles that
shown in FIG. 3.
[0045] The extent to which the slidable sections 352a are displaced
may be represented by the extent to which the hinges 346a have
opened, or by the extent to which slidable portion edges 380 have
shifted in relation to the adjacent fixed section edge 381. When
the expansion flap assembly 300 has been folded as far as the
carton C design requires and the slidable section has reached the
second position P.sub.2, the assembly 300 may be attached to the
end flaps (not shown) or otherwise folded and closed as described
herein.
[0046] With reference now to FIG. 6, an expansion panel assembly
400 includes a fixed section 450a and slidable sections 452a. The
expansion panel assembly 400 further includes at least one means
for cooperative relief. Means for cooperative relief includes one
or more relief apertures 340a and one or more expansion cuts 344a.
In this embodiment, the expansion cuts 344a extend to the edge of
the expansion panel 436a.
[0047] The slidable sections 452a are moved downwardly from a first
position P.sub.1 to a second position P.sub.2 (not shown) as the
expansion panel assembly 400 is folded along fold lines 422a, 438a.
The extent to which the slidable sections 452a are displaced may be
represented by the extend to which the sidable portion edges 480
are displaced or shifted in relation to the fixed section edge
481.
[0048] In certain embodiments, the end flap 120a may include the
means for cooperative relief described with regard to end flap
136a. Additionally, as understood by those skilled in the art, the
hinge 146a may be positioned proximate the fold line 122a.
[0049] The present invention has been illustrated in relation to
particular embodiments which are intended in all respects to be
illustrative rather than restrictive. Those skilled in the art will
recognize that the present invention is capable of many
modifications and variations without departing from the scope of
the claims. For example, as used herein, directional references
such as "top", "base", "bottom", "end", "side", "inner", "outer",
"upper", "middle", "lower", "front" and "rear" do not limit the
respective walls of the carton to such orientation, but merely
serve to distinguish these walls, flaps, and panels from one
another. Any reference to a hinged connection should not be
construed as necessarily referring to a junction including a single
hinge only; indeed, it is envisaged that hinged connection can be
formed from one or more potentially disparate means for hingedly
connecting materials.
[0050] The the above-described embodiments are merely exemplary
illustrations of implementations set forth for a clear
understanding of the principles of the invention. Variations,
modifications, and combinations may be made to the above-described
embodiments without departing from the scope of the claims. All
such variations, modifications, and combinations are included
herein by the scope of this disclosure and the following
claims.
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