U.S. patent number 3,885,732 [Application Number 05/455,181] was granted by the patent office on 1975-05-27 for carton with easy opening reclosure.
This patent grant is currently assigned to Fiberboard Corporation. Invention is credited to Thomas W. Foster.
United States Patent |
3,885,732 |
Foster |
May 27, 1975 |
Carton with easy opening reclosure
Abstract
A carton end closure comprises major flaps and minor flaps
hingedly connected to walls of the carton. The outer major flap
contains a first pair of diagonally extending lines of weakness for
partially opening the carton and a second pair of diagonally
extending lines of weakness which are utilized to complete the
opening thereof.
Inventors: |
Foster; Thomas W. (Palo Alto,
CA) |
Assignee: |
Fiberboard Corporation (San
Francisco, CA)
|
Family
ID: |
23807717 |
Appl.
No.: |
05/455,181 |
Filed: |
March 27, 1974 |
Current U.S.
Class: |
229/208; 229/155;
229/222 |
Current CPC
Class: |
B65D
5/541 (20130101) |
Current International
Class: |
B65D
5/54 (20060101); B65d 005/54 () |
Field of
Search: |
;229/37,39,51RC,51WB,51D,51TS,51TC |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Moorhead; Davis T.
Attorney, Agent or Firm: Beck; Robert A.
Claims
What is claimed is:
1. A carton structure having an easy opening feature, said carton
structure comprising side walls, a front wall, a back wall, a
bottom closure and a top closure, said top closure comprising
a. minor flaps hinged to said side walls,
b. an inner major flap hinged to said front wall,
c. an outer major flap hinged to said back wall, said outer major
flap folded over and sealed to said other flaps only in areas
closely adjacent its side edges and a front edge thereof to form
said top closure,
d. a tab formed in said outer major flap medially of the front edge
thereof,
e. a first pair of lines of weakness extending diagonally outwardly
and backwardly from said tab toward the corners of said outer major
flap remote from said front edge,
f. a second pair of lines of weakness extending from medial
portions of said first pair of lines of weakness diagonally
outwardly and forwardly towards the corners of said outer major
flap adjacent said front edge, and
g. cutaway portions at side edges of at least one of (1) said inner
major flap and (2) both of said minor flaps, so arranged that said
outer major flap is sealed only to said inner major flap in areas
adjacent its front edge and only to said minor flaps in areas
adjacent its side edges, whereby said closure may be opened by
first grasping said tab and pulling upwardly to split said outer
major flap along said first pair of lines of weakness and then
grasping said inner major flap and pulling upwardly to split the
remaining sealed portions of said outer major flap along said
second pair of lines of weakness.
2. The carton of claim 1 further comprising releasable means
securing said tab to said inner major flap.
3. The carton of claim 2 wherein said releasable means comprises
cut lines in said inner major flap extending only partially
therethrough.
4. The carton of claim 1 further comprising reclosure means formed
in said inner major flap to receive said tab and reclose said
carton.
5. The carton of claim 1 further comprising means in said inner
major flap for grasping and pulling said flap upwardly.
6. The carton of claim 1 wherein said cutaway portions are only at
the side edges of said inner major flap whereby, when said minor
flaps are folded inwardly first to form said top closure, portions
of said minor flaps are exposed to contact with said outer major
flap.
7. The carton of claim 1 wherein said cutaway portions are only at
the edges of said minor flaps proximate to said inner major
flap.
8. A carton blank comprising
a. a first side wall, a back wall, a second side wall, a front wall
and a manufacturer's glue lap serially connected to each other
along first parallel scorelines,
b. bottom closure flaps connected to said walls along a second
scoreline, and
c. top closure flaps connected to said walls along a third
scoreline, and including
d. minor flaps connected to said side walls, an inner major flap
connected to said front wall and an outer major flap connected to
said back wall,
e. cut means forming a tab at the medial portion of a free edge of
said outer major flap remote from said third scoreline,
f. a first pair of lines of weakness in said outer major flap
extending diagonally toward the corners of said outer major flap
proximate to said third scoreline, and
g. a second pair of lines of weakness in said outer major flap
extending from medial portions of said first pair of lines of
weakness diagonally toward the corners of said flap proximate said
free edge thereof, and
h. cutaway portions at side edges of at least one of (1) said inner
major flap and both said minor flaps so arranged that when said
outer major flap is folded over on top of said other flaps to form
a top closure it contacts only said minor flaps along its side
edges and only said inner major flap along its front edge.
9. The carton blank of claim 8 further comprising cut means in said
inner major flap adapted to receive said tab and thereby to reclose
a carton formed from said blank.
Description
BACKGROUND OF THE INVENTION
Efficient and expeditious opening of sealed paperboard cartons has
long been a problem in the packaging industry. One method for
opening such cartons is to provide a removable tear strip which may
be ripped away. A second method is to provide lines of weakness in
one of the carton end closures to facilitate opening, as
exemplified in U.S. Pat. Nos. 1,985,590, 2,151,202 3,366,311 and
3,438,566. The recently developed usage of very strong adhesives,
for example hot melt adhesives or polyethylene coatings, has
accentuated the problem. The bond formed by these adhesives is
stronger than the paperboard itself and use of ordinary opening
features is unsatisfactory, particularly when a tight, vermin-proof
seal may be required as in the packaging of raisins, prunes and the
like.
SUMMARY OF THE INVENTION
It is an object of the invention to solve the above briefly noted
problems by providing an opening device in the closure flaps of a
tightly sealed carton whereby the carton may be opened easily and
expeditiously.
In the preferred embodiment, the carton comprises front, back and
side walls and a manufacturer's glue lap hingedly connected to one
of said walls so that the carton may be formed into a tubular
structure. Any suitable end flap configuration may be utilized for
the bottom closure of the carton. The top end closure comprises
minor flaps hinged to each of the side walls, an inner major flap
hinged to the front wall and an outer major flap hinged to the back
wall. The configuration of the inner major flap and the minor flaps
is such that when these flaps are folded inwardly and the outer
major flap is then folded down on top of them to form the closure
the inner surface of the outer major flap contacts and is sealed to
the inner major flap adjacent the front edge of the carton and to
the minor flaps adjacent the sides of the carton.
A tab is formed near the center of the front edge of the outer flap
and a pair of lines of weakness lead from the tab diagonally
backwardly and outwardly toward the rear corners of said flap. When
the tab is grasped and pulled upwardly, said flap tears along the
lines of weakness releasing the center section thereof from the
inner flaps. A second pair of lines of weakness lead from points
intermediate the ends of said first pair diagonally forwardly and
outwardly toward the front corners of the outer major flap. After
completion of the aforementioned partial opening of the closure,
the inner major flap may be grasped and pulled upwardly, tearing
the remainder of the outer major flap along the second pair of
lines of weakness to complete the opening. Means may be provided in
the inner major flap to cooperate with the tab to form a reclosure
feature.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects of the invention will become apparent from the
following description and accompanying drawings wherein
FIG. 1 is a plan view of the outer surface of a paperboard blank
adapted to be erected into a carton embodying the invention;
FIG. 2 is a perspective view, in part, of the erected carton with
the top closure partially formed;
FIG. 3 is a similar view of the completed carton;
FIG. 4 is a similar view showing the carton after the first step in
opening the carton has been completed;
FIG. 5 is a similar view showing the carton completely opened,
and
FIG. 6 is a similar view showing the reclosure feature in
operation.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
The blank of FIG. 1 comprises side wall 11, back wall 12, side wall
13, front wall 14 and manufacturers glue lap 15 connected
consecutively along scorelines 16, 17, 18 and 19. Bottom closure
flaps 21, 22, 23, and 24 are hinged respectively to said walls
along scoreline 20. The top closure flaps are hingedly connected to
the walls along scoreline 25, which is parallel to scoreline 20,
with minor flaps 26 and 28 hinged respectively to side walls 11 and
13, outer major flap 27 hinged to back wall 12 and inner major flap
29 hinged to front wall 14.
The side edges of minor flaps 26 and 28 remote from outer major
flap 27 are partially cut away to form inwardly extending diagonal
side edges 31 and 32 and vertically extending side edges 33 and 34
respectively. In a similar manner, the side edges of inner major
flap 29 are cut away to form diagonal inwardly extending edges 36,
36 and vertically extending edges 37, 37.
A cutout area 38 is formed in the medial area of the free edge of
inner major flap 29 remote from scoreline 25. A first cut line 39
extending through inner major flap 29, is formed parallel to
scoreline 25, medially with respect to the side edges of said flap.
Cut line 39 is spaced from scoreline 25 and is of a length suitable
to receive a closure tab on outer major flap 27, to be described
hereinafter. Second cut line 41 is formed in scoreline 25 medially
of inner major flap 29 with respect to its side edges, and
preferably slightly shorter than cut line 39. In contrast to cut
line 39 which extends entirely through the flap, cut line 41
extends only partially through the paperboard forming that flap. A
pair of third cut lines 42, 42, also extending only partially
through the paperboard forming inner major flap 29 extend inwardly
of the flap from the end edges of cut line 41 to junctures with the
aforementioned cut line 39.
A closure tab 43 is formed in outer major flap 27 medially of its
edge which is remote from and parallel to scoreline 25. Closure tab
43 is formed by two cuts, 44, 44 extending from the aforementioned
edge of outer closure flap 27 inwardly to scoreline 45 which is
parallel to said edge and joins the inner edges of said cuts 44,
44. In the final sealed carton the area of closure tab 43
corresponds to the area of inner major flap 29 inside cut lines 39,
42, 41 and 42 and is sealed thereto. A first pair of lines of
weakness 46, 46 in outer major flap 27 extend from the ends of
scoreline 45 diagonally outwardly and rearwardly of the flap to the
points where the side edges of said flap meet scoreline 25, that
is, at the junctures of said scoreline 25 with scorelines 16 and 17
respectively. A second pair of lines of weakness 47, 47, extend
from the medial area of said first pair of lines of weakness 46, 46
diagonally forwardly and outwardly to the ends of the free edge of
outer major flap 27 which is remote from scoreline 25.
Lines of weakness 46, 46, are shown as consisting of a series of
J-cuts and lines of weakness 47, 47, are shown as a series of
straight line cuts in the drawings. It should be understood that
these respective types of cuts are not critical and that any type
of lines of weakness which will permit the type of tearing required
is suitable.
To utilize the carton the blank may be folded suitably along
scorelines 18 and 16 and manufacturer's lap 15 then is sealed to
the inner surface of side wall 11 to form a tubular structure. The
tubular structure may then be squared up, the bottom closure flaps
suitably folded up and sealed and the contents inserted.
Referring now to FIG. 2 the carton is shown set up in tubular form
with the bottom closure sealed and ready for sealing of the top
closure. In this configuration, minor flaps 26, 28 have first been
folded inwardly and then inner major flap 29 has then been folded
inwardly to overlie said minor flaps. It should be understood that
the closure will perform equally well if the inner major flap is
folded first. As shown in FIG. 2, the aforementioned cutaway areas
at the sides of inner major flap 29 expose areas of minor flaps 26
and 28 adjacent their scorelines to contact with outer major flap
27 during sealing. Further, diagonal side edges 31, 32 of minor
flaps 26 and 28 substantially coincide with diagonal side edges of
inner major flap 29 so that there is substantially no overlap along
these contacting areas. This results in what is essentially a
single layer of paperboard at this juncture which assists in
obtaining a tight seal.
To complete the closure, outer major flap 27 is folded flat against
the inner flaps and sealed thereto. Preferably, this seal is
effected substantially only in areas adjacent the free edges of
outer major flap 27, that is, the areas in FIG. 2 where said outer
major flap contacts minor flaps 26 and 28, and in an area of inner
major flap 29 adjacent scoreline 25 having a width substantially
equal to the distance between scoreline 25 and cut line 39.
Any number of methods may be utilized to effect this selective
sealing. Conventional adhesives or hot melt may be selectively
pattern applied in the requisite areas. If the blank is coated with
a heat activatable adhesive, the areas not to be sealed may be
coated with an ink or other substance which inhibits sealing.
Alternatively, sealing may be effected by a properly shaped heated
bar which contacts only that portion of outer major flap 27 which
overlies the area to be sealed, or hot air may be directed only on
the requisite area for selective activation of the adhesive.
The closed and sealed carton is shown in FIG. 3. To open the
carton, tab 43 is grasped and pulled upwardly. The free edge of tab
43 may be formed to extend slightly beyond the corresponding edge
of outer major flap 27, if desired, to facilitate such grasping.
Upon pulling upwardly of tab 43, the area of inner major flap 29
between cut lines 39, 42, 41 and 42, which is sealed to said tab,
will delaminate from said inner major flap and thus release the
tab.
Upon further exertion of an upward pull on tab 43, outer major flap
27 will tear along lines of weakness 46, 46, permitting the central
portion of said flap to be pulled into an upright position
perpendicular to the original closure. It should be noted that due
to the selective sealing hereinbefore described, this portion of
outer major flap 27 between lines of weakness 46, 46, is
substantially not adhered to the underlying flaps, so that there is
little or no resistance to lifting of this portion.
At this point, after partially opening the closure, the carton is
in the configuration shown in FIG. 4. The central portion of outer
major flap 27 between lines of weakness 46, 46, extends upwardly
perpendicular to the original closure and the remaining portions
thereof lying outside said lines of weakness remain sealed to minor
flaps 26 and 28 and inner major flap 27. In order to complete the
opening one need only insert a finger in cut away portion of inner
major flap 29 and pull upwardly. Exertion of an upward force on
this flap causes those portions of outer major flap 27 which are
still sealed to the underlying flaps to tear along weakened lines
47, 47, permitting the inner major flap to be pulled upwardly and
open. At this point one need only fold the inner minor flaps
outwardly to finish opening of the carton to the configuration of
FIG. 5.
It should be noted that in the completed closure, lines of weakness
47, 47 substantially overlie the junctures formed by diagonal edges
31 and 32 of minor flaps 26 and 28 with diagonal edges 36, 36 of
inner major flap 29. Thus when tearing takes place along lines of
weakness 47, 47, the remaining portions of outer major flap 27
which remain sealed are separately sealed to minor flap 26, minor
flap 28 and inner major flap 29, and are all separated from each
other so as not to inhibit opening of all flaps.
If it is desired to reclose the carton after partial removal of the
contents, the inner flaps may be folded into closed position, tab
43 may be bent inwardly along scoreline 45 and the upright portion
of outer major flap 27 to which the tab is attached may be folded
to the closed position, with the tab inserted in cut line 39 to
lock the reclosure in place.
As can be seen from the foregoing, an efficient and easily operated
opening feature is provided for a tightly sealed carton. Further, a
reclosure feature may be incorporated therein.
* * * * *