Strengthening strut for rectangular container

A package of thin, flexible material for positioning an article contained within the package has an exterior container having generally the shape of a rectangular box made with first and second opposed main panel pairs joined at ninety degrees to form a tube of rectangular cross-section and a pair of end closures at opposite ends of said tube. An internal positioning frame exists within the exterior container. The internal positioning frame has a pair of generally parallel positioning panels, each such positioning panel being parallel to the first pair of main panels and both such positioning panels being connected to one of the second pair of main panels. A first positioning strut is connected between the parallel positioning panels and lies generally perpendicular to each of the parallel positioning panels and in spaced, generally parallel relation to the second pair of main panels. A second positioning strut is connected between the first positioning strut and at least one of the first pair of main panels. The second positioning strut lies generally parallel to said parallel positioning panels and in a plane intermediate the planes of said parallel positioning panels.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to packaging. More particularly, the present 
invention relates to a generally rectangular package of paperboard or 
other flexible material that contains an internal frame structure used to 
position and hold an article that is placed in the package. 
2. Description of the Prior Art 
Packaging has become an important part of the marketplace image of many 
products, in addition to serving to protect the products packaged. For 
many products of irregular shape, it is desired to package the product in 
a rectangular carton to simplify and regularize packing in cartons and to 
give a neat appearance to shelf displays. At the same time, it is often a 
goal of the package to display the product attractively through apertures 
or windows in the package. When a package is somewhat larger than the 
article it contains, it becomes necessary to use a structure internal to 
the outer walls of the package to position and hold the article relative 
to the apertures or windows. The same internal structure may also be used 
to cushion the article or to keep it from shifting freely within the 
package. 
In prior art packages, various folded and/or glued panels have been used to 
form the internal positioning structure. In one form of package often used 
for small products such as a roll-on deodorant bottle, the product has 
been positioned by means of a pair of parallel panels connected by a 
strut. The product rests between the parallel panels and it is constrained 
by the strut against motion in a direction parallel to the panels. Because 
the strut is a relatively narrow strip of paperboard, it may become warped 
or bent, permitting the product to escape the position that the internal 
positioning structure was designed to hold. An internal positioning 
structure having greater integrity and ability to hold a product securely 
would be a desirable improvement over the known prior art. 
SUMMARY OF THE INVENTION 
A package for positioning an article contained within the package has an 
exterior container having generally the shape of a rectangular box made 
with first and second opposed main panel pairs joined at ninety degrees to 
form a tube of rectangular cross-section and a pair of end closures at 
opposite ends of said tube. An internal positioning frame exists within 
the exterior container. The internal positioning frame has a pair of 
generally parallel positioning panels, each such positioning panel being 
parallel to the first pair of main panels and both such positioning panels 
being connected to one of the second pair of main panels. A first 
positioning strut is connected between the parallel positioning panels and 
lies generally perpendicular to each of the parallel positioning panels 
and in spaced, generally parallel relation to the second pair of main 
panels. A second positioning strut is connected between the first 
positioning strut and at least one of the first pair of main panels. The 
second positioning strut lies generally parallel to said parallel 
positioning panels and in a plane intermediate the planes of said parallel 
positioning panels. 
It is an object of the present invention to provide a rectangular carton 
with an improved internal structure for product positioning and holding. 
It is another object of the present invention to provide a rectangular 
carton with an additional strut to reinforce the other internal structural 
elements and enhance the integrity of the internal structure of the 
carton. 
It is a further object of the present invention to provide a rectangular 
carton with an additional internal reinforcing strut that is formed from 
paperboard that would otherwise be wastage. 
These and other objectives of the present invention will become apparent 
with reference to the drawings, the description of the preferred 
embodiment that follows and the appended claims.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
As best seen in FIG. 1, a blank 10 for a package in accordance with the 
present invention comprises a single flat piece of a flexible material 
such as paperboard that is die cut, scored and cut-through to produce a 
number of panels, flaps and struts. In the drawings, double lines indicate 
bend scores used to form fold lines. Single solid lines indicate cuts or 
free edges. Double lines alternating with single lines indicate 
alternating cuts and bend scores that together form cut-score fold lines. 
In overview, the blank 10 consists of generally rectangular panels 20, 30, 
40 and 50 with associated end flaps used to form an external container and 
additional panels 60, 70, 80, 90, 110, 120, 130 and bridge strut 100 used 
to form an internal positioning frame. All of the preceding panels and 
associated flaps are integrally formed in the single blank 10. Turning 
first to the left hand side of FIG. 1, one end of the blank 10 begins with 
generally rectangular side panel 20 having at its top and bottom 
boundaries auxiliary end flaps 21, 22 joined to the side panel 20 at 
respective, parallel fold lines 27, 28. At fold line 29 perpendicular to 
fold lines 27, 28, side panel 20 is joined to generally rectangular front 
panel 30, which has at its bottom boundary an end closure flap 32 joined 
to the front panel 30 at fold line 38 perpendicular to fold line 29. Tuck 
flap 34 is, in turn, joined to end closure flap 32 at fold line 37 
parallel to fold line 38. A product window 35 (which may be of any desired 
shape) is die cut out of the center of the front panel 30. A second 
generally rectangular side panel 40 is joined to front panel 30 at fold 
line 39 parallel to fold line 29. Second side panel 40 has at its top and 
bottom boundaries auxiliary end flaps 41, 42 joined to the second side 
panel 40 at respective, parallel fold lines 47, 48 perpendicular to fold 
line 39. Joined to second side panel 40 at fold line 49 parallel to fold 
line 39 is a generally rectangular back panel 50. Back panel 50 has an end 
closure flap 51 joined to its upper boundary at fold line 57 perpendicular 
to fold line 49. Tuck flap 53 is, in turn, joined to end closure flap 51 
at fold line 58 parallel to fold line 57. 
As will be seen below, the side panels 20, 40, being of the same size, and 
the front and back panels 30, 50, also being of the same size, form, 
respectively, the first and second main panel pairs. These main panel 
pairs 20, 40 and 30, 50 are folded at ninety degree angles so as to form a 
tube of generally rectangular cross-section that is the external container 
of the present invention. 
At fold line 59 begin the panels that form the internal positioning frame. 
A first, generally rectangular, internal side panel 60 is joined to the 
back panel 50 at fold line 59 parallel to fold line 49. Bridge strut 
support panel 70, which is roughly "L"-shaped, is joined to first internal 
side panel 60 at a cut-score fold line 69 parallel to fold line 59. A 
first positioning panel 80, which is generally rectangular but somewhat 
irregular in shape at its top and bottom edges, is joined to the bridge 
support panel 70 at cut-score fold line 79 parallel to fold line 69. 
Internal back panel 90, which is generally rectangular in shape but has a 
projecting tab 91 at its bottom edge, is joined to first positioning panel 
80 at cut-score fold line 89 parallel to fold line 79. 
Extending between the bottom horizontal leg portion of bridge strut support 
panel 70 and tab 91 of internal back panel 90 is a bridge strut panel 100. 
The bridge strut panel 100 is joined to the bridge strut support panel 70 
at a front fold line 108 and is joined to tab 91 of internal back panel 90 
at a rear fold line 109. 
A second positioning panel 110 is joined to internal back panel 90 at a 
cut-score fold line 99 parallel to fold line 89. Like first positioning 
panel 80, second positioning panel is generally rectangular in shape but 
somewhat irregular at its top and bottom edges. A horizontal strut support 
panel 120 shaped somewhat like a reversed "L" is connected to the second 
positioning panel 110 at cut-score fold line 119 parallel to fold line 99. 
Although in FIG. 1, it appears as if the left-most bottom end of the 
horizontal strut support panel 120 is connected to internal back panel 90, 
the boundary between these two panels is cut, leaving a free edge 128. A 
second internal side panel 130 of generally rectangular shape is connected 
to horizontal strut support panel 120 at cut-score fold line 129 parallel 
to fold line 119. 
The manner of folding, gluing and assembling the various panels shown in 
FIG. 1 to form a completed package 12 in accordance with the present 
invention is illustrated in a step-by-step sequence in FIGS. 2 through 6. 
FIGS. 7 through 9 show how an article is inserted in the erected package 
12 and the end closures put into place. The assembly sequence and product 
loading sequence will be described next. 
As seen in FIG. 2, the first step in the assembly sequence is to fold the 
horizontal strut support panel 120 and the second internal side panel 130 
downward at cut-score fold line 119 while also folding second positioning 
panel 110 upward slightly at cut-score fold line 99. As can be seen, this 
causes the free edge 128 of horizontal support panel 120 to separate from 
contact with internal back panel 90. At the same time, a patch 71 of glue 
or adhesive is applied to the bottom extended end of bridge strut support 
panel 70. Turning now to FIG. 3, it can be seen that the second step of 
assembly is to extend the folds at cut-score fold lines 99 and 119 to 
one-hundred eighty degrees in opposite directions so that panels 120 and 
130 lie on top of panel 110 and panel 110 lies on top of panel 90. This 
brings the free edge 128 of horizontal strut support panel 120 down in the 
vicinity of glue patch 71 where the leftmost extension of the horizontal 
strut support panel 120 is attached. The bottom, horizontal leg portion of 
panel 120 now covers the bridge support panel 100 but is not directly 
attached thereto. 
Referring now also to FIG. 4, it can be seen that the next step of assembly 
involves ninety degree folds made at fold line 59 between back panel 50 
and first internal side panel 60, at cut-score fold line 69 between bridge 
strut support panel 70 and first internal side panel 60, and at cut-score 
fold line 129 between horizontal strut support panel 120 and second 
internal side panel 130. In addition, the formerly flattened structure 
formed by panels 70, 80, 90, 100, 110 and 120 (FIG. 3) is erected by 
making ninety degree bends at cut-score fold lines 79, 89, 99 and 119 and 
also at fold lines 108 and 109, at opposing ends of the bridge strut panel 
100. The folds are made so that panel 90 rotates away from panel 110 and 
becomes parallel to and spaced from panels 70 and 120. Panels 80 and 110 
become perpendicular to panel 90. To hold this internal structure in 
place, a glue patch 56 is applied to the surface between back panel 50 and 
internal back panel 90, which now lie in contact with each other. 
FIGS. 5 and 6 show the remaining assembly of the exterior container. This 
occurs by further ninety degree bends at fold lines 29, 39 and 49, which 
cause the panels 20, 30, 40 and 50 to form a rectangular tube around the 
internal positioning frame structure formed by panels 60, 70, 80, 90, 100, 
110, 120 and 130. This folding sequence causes front panel 30 to lie in 
parallel, spaced relation to the composite structure formed by bridge 
strut support panel 70 and horizontal strut support panel 120. The ends of 
"L"-shaped panels 70, 120 affixed to each other at glue patch 71 form a 
first positioning strut that is connected between the positioning panels 
80, 110 and is supported at its center by bridge strut panel 100, forming 
the second positioning strut. To hold the internal positioning frame in 
place within the exterior container, internal side panel 130 is affixed to 
the interior of side panel 40 at a glue patch 46. 
With the side panels 20, 40, forming a first main panel pair, and the front 
and back panels 30, 50, forming a second main panel pair, assembled in the 
form of a rectangular tube, the package 12 is now ready for product 
insertion and closure. As best seen in FIGS. 7-9, an irregularly shaped 
product such as roll-on deodorant bottle 140 can be inserted into the 
package 12 at the tube end opposite the location of bridge strut panel 
100. Specifically, as shown in FIG. 8, the product 140 is inserted between 
first and second positioning panels 80, 110 (not visible in FIG. 8) to lie 
against internal back panel 90 and behind bridge strut support panel 70 
and horizontal strut support panel 120. The top 141 of the product 140 
comes into contact with or is adjacent to bridge strut panel 100, which 
extends generally perpendicular from rear fold line 109 at internal back 
panel 90 to front fold line 108, where horizontal strut support panel 120 
is affixed to bridge strut support panel 70 at glue patch 71. Thus, the 
strut extending between the first main panel pair 20, 40 is supported and 
maintained in position by bridge strut panel 100 so that it cannot easily 
be displaced and thereby permit product 140 to slip from its position. The 
product 140 remains attractively framed by product window 35 and contoured 
interior edges 72, 122 of panels 80 and 110, which follow the outlines of 
product window 35. The "L"-shaped interior edges 72, 122 of first 
positioning panel 70 and second positioning panel 120 form an internal 
aperture behind the product window 35 through which the product 140 is 
visible. 
As best seen in FIGS. 8 and 9, the end closures of the open ends of the 
rectangular tube formed by panels 20, 30, 40 and 50 are formed by first 
folding inwardly auxiliary end flaps 21, 41 and 22, 42 at their respective 
ends, then folding end closure flaps 51, 32 together with their respective 
tuck flaps 53, 34 to fit down inside the respective ends of the exterior 
container. To avoid interference with tuck flap 34, the outer corner of 
bridge strut panel 100 nearest rear fold line 109 is removed. In addition, 
no glue is placed behind tab 91 projecting from internal back panel 90 so 
that tuck flap 34 can rest between tab 91 and back panel 50. 
In summary, it can be seen that the present invention provides a package 
that can be manufactured as a flat blank and sold in that form for 
erection to form a package or container with an internal positioning frame 
that holds the contained product against both side to side motion and 
upward motion against the bridge strut panel 100. Moreover, it can be seen 
that the bridge strut panel 100 is formed from material extending between 
two panels that in prior designs was trimmed off in the die cutting 
process and became wastage. The finished package of the present invention 
is an attractive rectangular carton with tuck-in end closures that 
effectively positions the contained product in front of a double frame 
product window. 
Although a description of the preferred embodiment has been presented, it 
is contemplated that various changes could be made without deviating from 
the spirit of the present invention. For example, while the preferred 
embodiment shows two end closures with a tuck end construction, it will be 
seen that sealed flaps can be used as well. Moreover, it will be observed 
that a variety of product window shapes can be produced and that the 
package could be produced with some variation from exact ninety degree 
folds, so long as the basic internal positioning panel and strut structure 
is preserved. Accordingly, it is intended that the scope of the present 
invention be dictated by the appended claims, rather than by the 
description of the preferred embodiment.