U.S. patent application number 11/044423 was filed with the patent office on 2006-07-27 for paperboard container with locking flaps.
This patent application is currently assigned to Georgia-Pacific Corporation. Invention is credited to Randall P. Kornacki.
Application Number | 20060163333 11/044423 |
Document ID | / |
Family ID | 36695699 |
Filed Date | 2006-07-27 |
United States Patent
Application |
20060163333 |
Kind Code |
A1 |
Kornacki; Randall P. |
July 27, 2006 |
Paperboard container with locking flaps
Abstract
A container blank is provided which forms a container having a
pair of end wall panels defining access apertures therein and a
pair of side wall panels. The container blank also includes a
plurality of minor flaps adjacent to the end wall panels where at
least one of the minor flaps includes a horizontal fold line across
the midsection of the minor flap and at least one vertical fold
line that runs generally perpendicular to the horizontal fold line
and defines at least one folding tab member on one of the minor
flap locking tabs. Further, the container blank also has a
plurality of major flaps adjacent to the side wall panels, where at
least one of the major flaps has a receiving slot for engagement
with an associated locking tab. The resulting container provides
strength for use in storage including food product storage.
Inventors: |
Kornacki; Randall P.; (San
Francisco, CA) |
Correspondence
Address: |
PATENT GROUP GA030-43;GEORGIA-PACIFIC CORPORATION
133 PEACHTREE STREET, N.E.
ATLANTA
GA
30303-1847
US
|
Assignee: |
Georgia-Pacific Corporation
Atlanta
GA
30303
|
Family ID: |
36695699 |
Appl. No.: |
11/044423 |
Filed: |
January 27, 2005 |
Current U.S.
Class: |
229/104 ;
229/157 |
Current CPC
Class: |
B65D 5/0254 20130101;
B65D 5/001 20130101; B65D 5/4295 20130101; B65D 5/44 20130101 |
Class at
Publication: |
229/104 ;
229/157 |
International
Class: |
B65D 5/10 20060101
B65D005/10 |
Claims
1. A container blank for forming a paper container comprising: a
first end wall panel having a top, a bottom, a left side and a
right side, the first end wall panel defining a first access
aperture therein adjacent to the top; a first side wall panel
having a top, a bottom, a left side and a right side, wherein the
first side panel is connected along its left side to the right side
of the first end wall panel; a second end wall panel having a top,
a bottom, a left side and a right side, wherein the second end
panel is connected along its left side to the right side of the
first side wall panel and the second end wall panel defines a
second access aperture therein adjacent to the top; a second side
panel having a top, a bottom, a left side and a right side, wherein
the second side wall panel is connected along its left side to the
right side of the second end wall panel; a pair of top minor flaps
connected to the tops of the first end wall panel and the second
end wall panel, wherein each of the top minor flaps includes at
least one top locking tab thereon, a generally horizontal fold
line, and at least one fold line disposed generally perpendicular
to the horizontal fold line so as to define a movable tab member
adjacent to the top locking tabs; a pair of major top flaps
connected to the tops of the first side wall panel and the second
side wall panel, wherein the major top flaps include receiving
slots that engage the top locking tabs of the minor top flaps; a
pair of bottom minor flaps connected to the bottoms of the first
end wall panel and the second end wall panel, wherein the bottom
minor flaps include bottom locking tabs thereon; and a pair of
major bottom flaps connected to the bottoms of the first side wall
panel and the second side wall panel, wherein the major bottom
flaps include receiving slots that engage the bottom locking tabs
of the minor bottom flaps.
2. The container blank according to claim 1, wherein each of the
receiving slots of the major top flaps is defined by a perimeter
having a cut line extending around a major portion of the perimeter
and a fold line extending around a minor portion of the
perimeter.
3. The container blank of claim 1, wherein the bottom minor flaps
include a generally horizontal fold line.
4. The container blank of claim 1, further including at least one
stacking tab formed therein adjacent to the top thereof.
5. The container blank of claim 4, further including at least one
stacking tab receiving slot formed therein adjacent to the bottom
thereof.
6. The container blank of claim 1, further comprising a third
access aperture formed adjacent to the intersection of the bottom
of the first or second end wall panel and the top of the first or
second bottom minor flaps.
7. A paperboard container comprising: a pair of end wall panels
having a top and a bottom each defining access apertures therein
adjacent to the top; a pair of side wall panels disposed between
the pair of end wall panels having a top and a bottom; a pair of
top minor flaps connected to the tops of the end wall panels,
wherein each of the top minor flaps includes at least one top
locking tab thereon, a generally horizontal fold line, and at least
one fold line disposed generally perpendicular to the horizontal
fold line so as to define a movable tab member adjacent to the top
locking tabs; a pair of major top flaps connected to the tops of
the pair of side wall panels, wherein the major top flaps include
receiving slots that engage the top locking tabs of the minor top
flaps; a pair of bottom minor flaps connected to the bottoms of the
pair of end wall panels, wherein the bottom minor flaps include
bottom locking tabs thereon; and a pair of major bottom flaps
connected to the bottoms of the pair of side wall panels, wherein
the major bottom flaps include receiving slots that engage the
bottom locking tabs of the minor bottom flaps.
8. The paperboard container according to claim 7, further
comprising a biasing tab adjacent to each of the receiving slots of
the major top flaps that engage the top locking tabs.
9. The paperboard container according to claim 7, wherein the top
minor flaps define an upstanding support structure with an apex
along the horizontal fold line.
10. The paperboard container of claim 7 further including at least
one stacking tab extending from the top of the side wall
panels.
11. The paperboard container of claim 10, wherein the side wall
panels further define at least one stacking tab receiving slot
formed adjacent to the bottom thereof.
12. The paperboard container of claim 7, further comprising a
second access aperture formed adjacent to the intersection between
the bottom of the end wall panels and the top of the bottom minor
flaps.
13. The paperboard container of claim 7 wherein the pair of major
bottom flaps include a generally horizontal fold line and define an
upstanding support structure with an apex along the horizontal fold
line.
Description
FIELD OF THE INVENTION
[0001] The present invention is directed generally to a container
constructed from a paperboard blank. More particularly, aspects of
the present invention relate to a paperboard container that has
increased strength for material handling.
BACKGROUND OF THE INVENTION
[0002] In the shipping and packaging industry, laminated containers
are used for transporting dry materials and products. In general,
laminated containers are constructed from corrugated fiberboard
having adhesively bonded layers. These laminated containers are
generally constructed initially from a paperboard blank. One type
of laminated container is a field pack produce container. This type
of produce container has short wall panels connected to short top
flaps with slot openings for closing the container. An access hole
is generally located in the upper portion of each end of the short
wall panels to allow a person to grasp the container to easily move
and transport the container and to allow a hose or other device to
be inserted into the access hole to fill the interior of the
produce container with ice. With these types of produce containers,
insertion of a hand or the hose end into the access hole can cause
the paper material of the container to tear at the access hole and
continue into the slot in the short flap. Thus, over time the
container of this construction can become difficult to use and
become unlocked. Also, the structural integrity of the container
can be significantly reduced.
[0003] A need exists for containers that can be handled, moved and
filled with product without tearing under normal use. Further, a
need exists for paperboard containers that have increased strength
for stacking. Specifically, a need exists for containers that limit
or prevent damage to its contents when other containers are stacked
on top of it.
SUMMARY OF THE INVENTION
[0004] The present invention pertains to a paperboard container
with increased strength for material handling operations and
improved locking function.
[0005] In an aspect, there is provided a locking container that is
resistant to tearing forces applied thereupon. Flaps which extend
from endwalls and sidewalls of the container may be connected to
compose a container top. Locking tabs located on minor flaps
adjacent to endwalls at a fold line, engage receiving slots located
at major flaps adjacent to sidewalls across a fold line. In another
aspect, access holes are provided on the endwalls to facilitate
movement of the container and for other purposes.
[0006] In yet another aspect, the invention provides a container
with locking mechanisms that lift the top of the container so as to
provide improved protection for contents of the container against
damage. When multiple containers are stacked vertically, folding
tab elements may be used to connect the top flaps of the container
and protect the contents inside of the container.
[0007] In another aspect of the invention, a container may include
support structures for protecting the contents of the container
when stacked with other containers. A support structure may be
formed by a fold line construction on a flap with locking tabs that
are manipulated into receiving slots of flaps. Containers
possessing these support structures may be stacked vertically to
reduce the risk that the contents of lower containers may be
damaged or crushed by the weight of containers located above the
lower containers.
[0008] The above and other aspects, features and advantages of the
present invention will be readily apparent and fully understood
from the following detailed description of preferred embodiments,
taken in connection with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a top plan view of a container blank according to
one or more aspects of the present invention.
[0010] FIG. 2A is a perspective view of a partially closed
container erected from the blank illustrated in FIG. 1.
[0011] FIG. 2B is a perspective view of another partially closed
container erected from a blank similar to the one illustrated in
FIG. 1.
[0012] FIG. 3 is another perspective view of the container of FIG.
2A erected from the blank illustrated in FIG. 1.
[0013] FIG. 4A is a side view of the container illustrated in FIG.
3.
[0014] FIG. 4B is a side view of the container illustrated in FIG.
2B where the container is fully closed.
[0015] FIG. 5 is an end view of the container illustrated in FIG.
3.
[0016] FIG. 6 is a top view of the container of FIG. 3 constructed
from the blank illustrated in FIG. 1.
[0017] FIG. 7 is a bottom view of a container constructed from the
blank illustrated in FIG. 1.
[0018] FIG. 8 is a top view of a container similar to that shown in
FIG. 3 but with an alternative locking arrangement.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] FIG. 1 illustrates a preferred construction of a
knocked-down-flat ("KDF") container blank 100. The blank 100 is
used to construct a rectangular shaped container, although other
configurations are possible, such as a cube shape. In a general
construction, blank 100 includes two side wall panels 106 and two
end wall panels 107 connected to four top flaps and four bottom
flaps, the boundaries of which are formed by vertical fold lines 77
and horizontal fold lines 120, 140. For reference purposes, the
fold lines are depicted as broken lines in FIG. 1. As used herein,
a fold line may be a thin band of a weaken region of material. The
thin band can be a specific area on a blank formed by conventional
manufacturing methods in the paperboard art. Nevertheless, the fold
line may be simply a predetermined area for folding along a part of
the blank without a weaken area. The KDF container may be
constructed by securing together the edges of a blank including the
aforementioned panels.
[0020] With continued reference to FIG. 1, the top flaps and bottom
flaps are provided to form major flaps and minor flaps generally
for a rectangular shaped container. Specifically, the major flaps
extend from the side wall panels 106 and the minor flaps extend
from the end wall panels 107 of the blank 100. The major flaps and
the minor flaps may be used in shaping either the container top or
bottom portions of a fully constructed container. For ease of
explanation, the terms "major" and "minor" are used herein for
designating a relative lateral length dimension. In essence, a
major flap has a longer length than a minor flap. The major flaps
and the minor flaps may contain features to facilitate construction
of the container, to provide strength, support and rigidity to the
container. The perimeter shape of the flaps allows for interlocking
engagement. Further, the shape of the flaps provides a top covering
or a floor base for the contents within the container.
[0021] In a preferred construction, the blank 100 includes two sets
of opposing minor flaps on the end wall panels 107. This minor flap
arrangement defines top minor flaps 108 and bottom minor flaps 109
both having locking protrusions. Top minor flaps 108 have the same
general perimeter shape including a moveable locking tab 150.
Locking tab 151 is disposed on bottom minor flap 109 and may be
formed as a fixed tab. Both top minor flaps 108 and bottom minor
flaps 109 have horizontal or longitudinal fold lines 110 spanning a
midsection portion. The top minor flaps 108 include transverse fold
lines 111 which are generally perpendicular to longitudinal fold
line 110 and are disposed laterally to the right and left ends of
the top minor flaps 108. This configuration of the transverse fold
lines 111 defines folding tabs 112 as part of locking tabs 150. The
folding tabs 112 pivot about the respective transverse fold line
111.
[0022] With continued reference to FIG. 1, a preferred construction
of blank 100 includes two sets of opposing major flaps disposed on
the side wall panels 106 which define top major flaps 113 and
bottom major flaps 114. The top major flaps 113 and bottom major
flaps 114 contain die cut receiving slots 115, 117, respectively.
These slots 115, 117 are configured to matingly engage in a
reliable locking type connection with the locking tabs 150, 151 of
the corresponding top minor flaps 108 and bottom minor flaps 109.
The connection between the locking tabs and receiving slots
withstands forces from handling operations, such as container
filling, loading, movement and stacking. The connection between the
locking tabs and slots may be purposely disabled under user
operation without destroying the integrity of the container.
[0023] In a preferred construction, the receiving slot 115 of the
top major flap 113 includes a biasing tab 180 which pivots upon
fold line 181. In operational engagement with locking tab 150,
biasing tab 180 provides a biasing force against the locking tab
150 and surface of the top major flap 113. In particular, the
biasing force may be upwardly directed for improved locking
performance with locking tab 150. The geometric shape and size
characteristics of the receiving slots 117 vary with respect to the
characteristics of the locking tabs 151 on the bottom minor flaps
109. Specifically, the receiving slots 117 disposed on the bottom
major flaps 114 may be characterized as having a narrower slot
width than the slots 115 disposed on the top major flaps 113.
[0024] End wall panels 107 may include material handling or access
hole feature, such as a die cut aperture 170. In a preferred
construction, the die cut apertures 170 are disposed on the end
wall panels 107 near the location of a horizontal fold line 120
shown in FIG. 1. Horizontal fold line 120 defines a boundary
between the top major flaps 113 and side wall panels 106, and top
minor flaps 108 and end wall panels 107 of container blank 100.
[0025] The location of die cut aperture 170 on end wall panels 107
provides improved resistance or near elimination of tearing of the
paperboard material under normal use conditions. The synergistic
arrangement of the end wall panels 107 and die cut aperture 170 in
combination with locking tabs 150 advantageously provides improved
structural integrity. This is due in-part in that the top minor
flaps 108 do not possess slots which can weaken the structural
integrity of a panel when under a shearing force. The improved
tear-out resistance is provided by the respective locations of
locking tabs 150 of top minor flaps 108 and corresponding receiving
slots 115 of top major flaps 113. Specifically, locking tabs 150
are located on the top minor flaps 108 while the corresponding
receiving slots 115 are located on the top major flaps 113. In this
inventive arrangement, a vertical lifting force may be applied to
the die cut aperture 170 to lift the container. This lifting force
creates an associated shearing stress which is distributed
throughout the top minor flap 108 above die cut aperture 170.
Advantageously, improved strength is provided when die cut aperture
170 is used in a handling operation to move a formed container and
its associated contents.
[0026] Die cut aperture 170 allows access to the contents of the
container and may be used for inserting ice or slurry. With
continued reference to FIG. 1, an access hole 178 may also be used
for filling the erected container with a coolant such as ice
slurry, or may further be used for material handling. In the mode
of material handling, the access hole 178 may serve as a grip
feature for lifting the erected container. Further, when multiple
containers are located tightly together for storage or
transportation, an elongated strap may be run into one access hole
178 and out the access hole 178 on the opposite face to hold the
containers either to a palette or to other containers, allowing for
tighter and more secure transportation or storage of the
containers.
[0027] With reference to FIG. 1, in a preferred construction, blank
100 includes stacking tabs 125 that extend from side wall panels
106 and top horizontal fold line 120. Stacking tab receiving slots
130 are generally positioned along the bottom edge of side wall
panels 106 abutting bottom horizontal fold line 140 defining the
boundary between side wall panels 106 and the bottom major flaps
103. When a container is erected, the engagement of the stacking
tabs 125 in the receiving slot 130 assist in stabilizing a columnar
stack of containers. It should be recognized that the length of
stacking tabs 125 can be varied according to the intended use of
the container and desired stabilization performance.
[0028] FIG. 2A illustrates a partially closed erected container 200
from blank 100 illustrated in FIG. 1. The container top surface 201
may be formed by securing top minor flaps 108 to top major flaps
113. Specifically, locking tab 150 may be folded along both
horizontal fold line 110 and longitudinal fold line 111 to form
folding tab 112 on each end of the top minor flap as a result of a
pivoting action along the transverse fold line 111. Folding tab 112
may be pivoted along the transverse fold line 111 so that it lies
generally underneath the remainder of the top minor flap 108.
Subsequently, the two locking tabs 150 on each end of each top
minor flap may be inserted into the corresponding receiving slots
115 located on one end of each of the top major flaps 113.
[0029] FIG. 3 illustrates a perspective view of container 200
erected from blank 100 that has been fully closed. Container 200
includes minor flaps 108 with the locking tab 150 and folding tab
112. Side wall panels 106 have top major flap 113 which includes a
receiving slot 115. As shown in this figure, the locking tab 150
and the folding tabs 112 of top minor flaps 108 and receiving slots
1 15 of top major flaps 113 have been engaged to fully close
container 200. In operation, the locking tabs 150 extend into and
are configured to engage the receiving slots. In addition, the
folding tabs 112 extend toward the receiving slots 115 and engage
the biasing tabs 180. In this way, the biasing tabs 180 exerts a
resistive force on the folding tab 112 to bias the locking tab 150
into engagement with the receiving slots 115 so the locking tabs
150 are held in engagement with the top major flaps 113 to create a
reliable locking connection.
[0030] The connection between the folding tabs 112 and the
receiving slots 115 connect the flaps 108 and 113 so as to form a
container top 201 that serves to enclose products within the
container 200. In a further aspect, the top minor flaps 108 are
folded in such a way that it is not contiguous with the top major
flaps 113 but instead creates a raised support structure 260 with
horizontal fold line 110 serving as the apex of the raised support
structure 260. This apex allows another container 200 to be stacked
on top of the subject container 200 without crushing the contents
of the subject container 200.
[0031] As illustrated in the side view diagram of a container 200
of FIG. 4A, folding tabs 112 help to hold support structure 260
against the weight of other containers 200 stacked on top of it.
The two raised support structures 260 are formed from top minor
flaps 108 by folding along the respective fold lines 110 and
locking folding tabs 112 of top minor flaps 108 into their
corresponding receiving slots 115. In the locked position, the
raised support structures 260 formed by the top minor flaps 108 may
contact the bottom surface 203 of a supported container.
[0032] FIG. 7 illustrates a bottom view of container 200, depicting
the interaction of bottom major flaps 114 and bottom minor flaps
109 to form the bottom portion 203. Bottom minor flaps 109 include
a horizontal fold line 110 utilized when forming a connection with
corresponding bottom major flaps 114 at the receiving slots 117.
The receiving slots 117 in the bottom major flaps 114 allow the
corresponding locking tab 151 to be inserted therein. The
engagement creates a reliable connection that holds bottom minor
flaps 109 and bottom major flaps 114 so as to create a bottom or
base of the container. Bottom portion 203 provides a lower support
to container 200 and encloses the contents in the container to be
transported therein.
[0033] FIG. 2B illustrates an embodiment of a partially closed
container 300 erected from a blank generally similar to the blank
illustrated in FIG. 1. Container 300, however, includes locking
tabs 150 that possess folding tabs 112 on both the top minor flaps
108 and the bottom minor flaps 109 and receiving slots 115 in both
the top major flaps 113 and bottom major flaps 114. In such an
embodiment, container 300 will include bottom support structures
362 formed from bottom minor flaps 109 (with locking tab 150) of
the container 300 as illustrated in FIG. 4B that is identical to
the support structure 260 described above. Container 300 and
similar ones may be stacked vertically so that the top raised
support structure 260 and bottom support structures 362 of stacked
containers can engage each other.
[0034] Therefore, containers 200 and 300, possessing either top
support structures 260 and/or bottom support structures 362 stacked
for storage or transport, protect the contents of the containers
during stacking and transportation by leaving the generally more
vulnerable top surfaces 201, 301 of the storage area of the
container free from a downward gravitational load from other
containers stacked above. The integrity of a container and the
location, structure, and geometry of the support structures prevent
the contents of the container from being crushed or damaged. For
example, numerous containers may be filled with food product, such
as broccoli, and stacked for temporary storage in a cold storage
warehouse. The noted containers reduce the risk that the food
product stored in the containers on a lower part of the stack will
be crushed or otherwise damaged by the weight of the containers on
the upper part of the stack. The weight of the containers may be
supported by the frame support structures located at the top end of
the end wall panels, rather than bending the top surface of the
container which risks damage to the product within the container
interior.
[0035] Referring to FIG. 4B, bottom support structures 362 of
container 300 allow a significant portion of the bottom surface 303
of the container to remain in an elevated state with respect to the
floor surface or other support surface. It may be advantageous for
certain products, for example produce and other food or perishable
items, to be elevated off of the ground to reduce the risk of
decay, contamination, or physical damage to the perishable
contents. The container also allows air to reach the food contents.
Support structures formed on the bottom portion of the container
provides support and lifts most of the bottom portion of the
container off the floor and prevents damage to the contents.
[0036] Containers 200 and 300 facilitate the storage and
transportation of contents while also protecting the contents'
integrity. Containers 200 and 300 may be used for transporting a
large array of products ranging from perishable produce and
confectionary items to wholesale products. Many common products,
including produce, exhibit a propensity for damage or injury as
containers of produce are often stacked tightly to maximize storage
or transit ground space. Accordingly, when stacking multiple like
containers 200 or 300, stacking tabs 125 may be used to assist in
stabilizing the containers stacked in a columnar fashion. In these
containers, two stacking tabs 125 extend upward generally along
each of the side wall panels 106 of the container. When a second
container is placed directly on top of a first container, the four
stacking tabs 125 may slidably engage the associated stacking tab
receiving slots 130 of another container. Stacking tab receiving
slots 130 are generally positioned along the bottom edge of side
wall panels 106. The extended vertical height of the stacking tabs
125 can be adjusted to engage the receiving slot 130 and provide
for lateral support when multiple containers 300 are stacked
together.
[0037] As seen from the illustrative end view in FIG. 5, container
200 also contains handle die cut aperture 170 that provides
improved tear-out resistance over prior container designs. In a
preferred construction, end wall panels 107 may include an access
hole 178 which may be used for filling the erected container with a
coolant such as ice slurry, or may further be used for material
handling.
[0038] Containers may be constructed from blanks, such as the one
illustrated in FIG. 1, in a variety of steps. The blanks may have
slots precut and fold lines demarcated and formed so as to
facilitate construction of a container. The container walls and
flaps may be formed by folding along the folding lines and locking
tabs and stacking tabs may be manipulated as desired. Further, glue
strip 199 provides a location for placement of an adhesive to
assist the container in maintaining its structural integrity and to
provide further support.
[0039] A preferred folded configuration of container 200 is
illustrated in the top view of a container in FIG. 6. Top minor
flaps 108 sit on top of the top major flaps 113 in each of the four
corners proximate to the connection between the top major flaps 113
and top minor flaps 108.
[0040] FIG. 8 illustrates an alternative locking arrangement of
container 200. Container 200 may be folded using a "French Fold"
lock resulting in a secure closure of the container. In such a
"French Fold" lock arrangement, one end of the container 200 has
minor flaps 108 with locking tabs 150 engaging the receiving slots
115 of the major flaps 1 13. The opposing end of the container 200
includes an overlapping arrangement of the minor flap 108 so that
it is disposed between both the major flaps 113. In operation, an
upward movement of the minor flap is resisted by the major flap 113
disposed on top of the minor flap. In such an arrangement, the
container 200 may be locked quickly by using locking tabs at one
end of the container and an overlapping flap arrangement at the
other end. It should be recognized that the minor flap and the
major flaps forming the overlapping arrangement can be provided
without locking tabs and receiving slots. Hence, an alternative
container can have at least one end of the container with the
locking tabs and receiving slot construction and the other end can
have to secure locking configuration formed with overlapping
flaps.
[0041] It is noted that the features of the container blank
individually and/or in any combination, may improve locking
performance, structural integrity and other benefits of a formed
container. While the various features and aspects of the container
blank work together to achieve the advantages previously described,
it is recognized that individual features and sub-combinations of
these features can be used to obtain some of the aforementioned
advantages without the necessity to adopt all of these features.
For example, a blank may be used to form a paperboard container
that can be resistant to tearing forces applied thereupon. Flaps
which extend from end wall panels and side wall panels of the
container may be connected to compose a container top. Locking tabs
located on minor flaps may engage receiving slots located at major
flaps. The paperboard container may have an access hole in the end
wall panels.
[0042] While the invention has been described with respect to
specific examples including presently preferred modes of carrying
out the invention, those skilled in the art will appreciate that
there are numerous variations and permutations of the above
described blank, and container and techniques. Thus, the spirit and
scope of the invention should be construed broadly as set forth in
the appended claims.
* * * * *