US3237842A

US3237842A - Carton end closure with easy opening feature

Info

Publication number: US3237842A
Application number: US348423A
Authority: US
Inventors: Robert L Esse
Original assignee: General Mills Inc
Current assignee: General Mills Inc
Priority date: 1964-03-02
Filing date: 1964-03-02
Publication date: 1966-03-01
Anticipated expiration: 1983-03-01

Description

March I, 1966 R. L. ESSE 3,237,342

CARTON END CLOSURE WITH EASY OPENING FEATURE Filed March 2, 1964 ,2 Sheets-Sheet 1 FIG. 7

INVENTOR. ROBERT L. ESSE FIG. 2 f zfi ATTORNEY March 1, 1966 R. L. ESSE 3,237,342

CARTON END CLOSURE WITH EASY OPENING FEATURE Filed March 2, 1964 2 Sheets-Sheet z I NV ENTOR.

ROBERT L. ESSE BY ait Q ATTORNEY United States Patent 3,237,842 CARTON END CLOSURE WITH EASY OPENING FEATURE Robert L. Essa, Minneapolis, lVIiniL, assignor to General Mills, Inc, a corporation of Delaware Filed Mar. 2, 1964, Ser. No. 348,423 6 Claims. (Cl. 229-51) The present invention relates to improvements in end closures for cartons. More particularly, the present invention pertains to a sealed carton end closure which is simple to open.

Many products require an enclosing carton for properly protecting such products. Some cartons which are used for this purpose are made without a separate liner for enclosing such products. A number of such cartons when tightly closed are somewhat difficult to open without the use of special tools or opening features.

One feature of the present invention resides in providing an easy opening carton end closure which can be tightly sealed on standard packaging equipment.

Another feature of the present invention resides in providing an easy opening carton end closure for a linerless carton which can be tightly sealed and thereby resist sifting and insect infestation.

Other features and advantages of the invention will be apparent from the following description in which certain preferred embodiments of the invention are disclosed.

In the drawings which form a part of this application:

FIGURE 1 is a plane view of a blank used for forming a carton according to the present invention;

FIGS. 2 and 3 are perspective views of the carton blank of FIG. 1 folded to complete the carton with the top closure flaps in the process of being folded;

FIG. 4 is a perspective view of the top of the carton of FIGS. 2 and 3 but with the top closure flaps folded to close the carton;

FIG. 5 is a perspective view of the carton of FIGS. 2 to 4 after the tear strip has been removed;

FIG. 6 is a perspective view of the tear strip that has been removed from the carton of FIG. 5; and

FIG. 7 is an enlarged detailed view of a portion of one of the carton top closure flaps illustrating the detail of the preferred form of the slits provided to form the tear paths for the tear strip.

FIG. 1 is a plane view of a blank 10 used for forming the carton of the present invention. The blank 10 is formed out of all bleached board with the inner layers bleached in a different process than the outer layers which results in a less bulky board with less fiber direction. Because of this lack of fiber direction, the tearing of this board normally lacks straight line orientation.

The blank 10 is comprised of a first side panel 12, a second side panel 14, a third side panel 16, a fourth side panel 18, and a glue panel 20. The

various panels

12, 14, 16, 18 and 20 are attached along

score lines

22, 24, 26 and 28. Bottom closure flaps 30, 32, 34 and 36 are hingedly connected to the lower edges of the

panels

12, 14, 16 and 18, respectively. The

panels

12, 14, 16, 13 and 20 will be folded along the

score lines

22, 24, 26 and 28 to form a tubular body which is rectangular in cross section as illustrated in FIG. 2.

To secure the carton in its tubular shape, the glue panel 20 is suitably adhered to the inner surface of the side panel 18. That is, the glue panel 20 will be inside the side panel 18 and on the inside of the carton as it appears in FIG. 2. The bottom end of the carton has been closed by folding the

bottom closure flaps

30, 32, 34 and 36, across the tubular bottom end of the carton. As is known in the art, the

closure flaps

32 and 36 are ice first folded across the bottom end opening, then the flap is folded across the

flaps

32 and 36, and then the flap 34 is folded across flap 3d. The flaps 3t), 32, 34 and 36 are held in this folded position by a suitable adhesive placed between at least portions of the contacting surfaces thereof.

Referring again to FIG. 1, the top end of the carton includes outer end closure flap 3S, inner end closure flap 40, outer end closure flap 42 and inner end closure flap 44. Closure flaps 38,

4t

42 and 44 are hingedly connected to the upper edges of the

panels

12, 14, 16 and 18, respectively, along a score line 46.

The closure flap 38 has a tear strip portion which lies between a pair of weakened

tear lines

48 and 50 which are parallel to and spaced from the hinged connection of the side panel 12 and the closure flap 38. The weakened

tear lines

48 and 50 are comprised of spaced

slits

52 and 54, respectively, which are inclined at an angle to the direction of tear of the weakened tear lines themselves, at least one

slit

56 and 58, respectively, which is parallel to said direction of tear of the weakened tear lines, and at least one

angled slit

60 and 62, respectively, which extends into the tear strip portion of the closure flap 38. In addition, there are areas of adhesive resistive material, such as varnish, on the flap 38. These areas of adhesive resistive material are depicted by

numerals

64, 66, and 68.

The closure flap 42 is provided with spaced angled slits which have a certain configuration and location to provide a weakened tear line 72. These slits "70 are arranged in a row which defines the direction of tear of the weakened line '72 in the flap 42. This direction of tear is parallel to and spaced from the hinged connection of the flap 42. The flap 44 has a pair of

areas

45 and 47 of glue resistive material, such as varnish.

Turning now to the closing of the top end of the carton, in FIG. 2, the inner or opposed

end closure flaps

40 and 44 are shown folded across the upper end of the carton body. After the inner

end closure flaps

40 and 44 are folded over the upper end of the carton, an adhesive is applied to the inner surfaces, or those which will face downwardly, of the outer side panel closure flap 38 and the outer side panel closure fiap 42. The side panel flap 38 is then closed as shown in FIG. 3 to overlie the pair of opposing

inner flaps

40 and 44. It will be noted that in the preferred embodiment of the present invention the width across the narrow dimension of the closure flap 38 from its hinge line is equal to the narrow width of the carton opening so the flap 38 covers the entire carton end with its free edge 74 extending across the full narrow width of the carton opening to the opposite side of the carton when the flap 38 is in folded position as shown in FIG. 3. This free edge 74 will substantially abut the hinged connection of the flap 42.

The outer side panel flap 42 is then folded down to overlie the side panel flap 38 to complete the sealed end closure of the carton which appears in its closed form in FIG. 4. When the flap 42 is folded down as shown in FIG. 4 its weakened tear line 72 is in substantial alignment with the weakened tear line 50. As shown in FIG. 4, in the preferred embodiment, the side panel closure flap 42 extends from its hinge line the full width across the carton so it overlies the entire carton top opening with the exception of a portion 76 which is notched out to obtain access to a pull tab 78. The pull tab 78 is located at one end of the tear strip 80 which is shown removed in FIG. 6. The tear strip 80 extends fully across the top of the carton. The tear strip 80 includes a portion of the end closure flap 38 and an overlying portion of the end closure flap 42. One edge of the tear strip 80 is defined by the tear paths which follow the weakened tear lines 3 50 and 72 while the other edge of the strip is defined by the tear path which follows the weakened tear line 48. When the pull tab 78 is grasped and lifted upwardly from the carton top, the tear strip 30 will be torn from the carton top following the

tear paths

48, 50 and 72, as shown in FIG. 5.

Since the closure fiap 42 extends completely across the narrow width of the carton, its outer edge portion 82 as shown in FIG. 6, will be lifted off the top surface of the closure flap 38. While it will be recognized that this upper flap 42 could be shortened to coincide with the tear path 48 of the closure flap 38, the additional width gained by extending the flap 42 to equal the narrow width of the carton creates the flat broad top for the carton which makes a better surface for purposes of stacking the cartons and creates a better appearing carton.

It will be noted from FIG. 5 that in addition to the carton tearing along the

tear paths

48, 50 and 72, a number of flat closure flap surfaces are separated from each other while at least one pair of fiat closure flap surfaces are not separated from each other. The pull tab 78 is separated from the end closure flap 44. The edge extension 82 of the side panel closure flap 42 is separated from the upper surface of the side panel flap 38. The rear end of the tear strip 80 is separated from the end closure flap 40. To facilitate these separations, the various flap surfaces involved should not be securely adhered to each other. In the present embodiment of the invention, such involved surfaces are adhered to each other in a controlled manner. One method of obtaining this controlled adherence is to arrange the glue pattern which is applied to the involved carton surfaces in such a manner that glue would be placed on those areas in a specified pattern which would permit easy separation of the areas yet prevent their accidental separation, e.g.,

placing glue in some areas and being sure that other areas are free of glue. However, it has been found that it is expedient to accomplish the desired controlled adherence by using glue resistant material, such as varnish, on the areas of the carton end closure flaps in which no .bond is desired. This prevents the adhesive applied to such flaps from soaking into the carton material and forming a bond between the flaps where no bond is desired while at the same time permitting the adhesive to penetrate the flap material at the critical areas where a bond is required or wanted.

The glue resistant material patterns are shown generally at the

areas

64, 66, 68, 45 and 47 in FIG. 1. With glue applied to the entire surfaces of the

flaps

38, 40, 42 and 44 seen in FIG. 1, these particular glue resistant material patterns permit a tight sealing of these end closure flaps while at the same time providing an easy opening carton end closure.

FIG. 5 shows an open package constructed in accordance with the present invention with the tear strip removed. This permits access to the interior of the carton. The narrow areas 84- and 86 which are the remaining parts of the closure flaps 38 and 42 may be folded back as may the closure flaps 40 and 44, to completely open the top of the carton. It will be noted that the portion of the closure flap 38 lying between its weakened line 50 and its outer edge 74 is still positioned below and adhered to a portion of the closure flap 42. This is accomplished in the preferred embodiment by adhering the portion of the flap 38 lying between the shaded area 50 and the edge 74 to the inner surface of the portion of the flap 42 which overlies it.

An important feature of the carton structure is the arrangement of the slits which define the tear path on each side of the tear strip. These slits are shown enlarged in FIG. 7 which illustrates a portion of the closure flap 38. The row of slits which defines the weakened tear line 48 is comprised of a single slit 56 which is in substantial alignment with the general direction of tear of weakened line 48 and a series of angular slits 52 which 4 extend outwardly at an angle to the general direction of tear of weakened line 48. The first angled slit 60 of the weakened line 48 is long enough so as to be intercepted by a straight line extending in the general direction of the first slit 5a. In a like manner, the row of slits which defines the weakened tear line 50 is comprised of a single slit 58 which is in substantial alignment with the general direction of tear of weakened line 50 and a series of angular slits 54 which extend outwardly at an angle to the general direction of tear of weakened line 50. Here again, the first angular slit 62 extends into the tear strip portion of the flap 38 a sufficient distance so as to be crossed by a straight line which extends from the first slit 58 in the general direction of the tear path of line 50.

An important feature of the invention is the position of the slits of the weakened line 72 of the closure flap 42 with respect to the slits 54 of the weakened line 50 of the closure flap 38. When the carton is closed as shown in FIG. 4, the weakened line 72 overlies the weakened line 50 in such a manner that the

angled slits

54 and 70 in the respective weakened

lines

50 and 72 are staggered, i.e., do not exactly overlie each other.

It will be noted in FIG. 7 that the pull tab 78 has a notch 88 and a notch 90 positioned on either side thereof. The apex of the notch 88 points to one end of the slit 56 while the apex of the notch 90 points to one end of the slit 58. This arrangement of the notches and the slits insures that when the pull tab 78 is lifted, substantially simultaneous tearing action will be directed along

slits

56 and 58 to the first

angled slits

60 and 62, respectively. and next along slits 52, 54 and 70.

The specific arrangements of the adhesive resistant areas 64 and 66 and the weakened

tear lines

48, 50 and 72 shown in the preferred embodiment of the present invention make a tear strip in the carton end closure flaps which is easily removable. This specific arrangement and the positioning of the slits which form the lines of tear of the weakened lines and the various glue patterns does not detract from providing a tightly sealed end closure and yet enhances the removability of the tear strip to obtain an improved carton.

In view of the principles set forth herein, I have shown some of the ways of carrying out the present invention and some of the equivalents which are suggested by these disclosures.

What is claimed is:

1. An easy opening carton including tubularly arranged side panels, and a closure at one end of said panels including closure flaps foldably connected to said side walls and folded into substantially right angular relation thereto, the closure flaps being folded into a common plane across said end of the carton, a first one of said closure flaps folded to overlie said carton end, said first flap having two weakened tear lines extending thereacross parallel to and spaced from the line of fold of said first flap, each of said two weakened tear lines including a series of spaced slits inclined at an angle to the direction of tear of said weakened tear line, a second closure flap folded to overlie said first flap, said second flap having a weakened tear line extending thereacross parallel to and spaced from the line of fold of said second flap and in substantial alignment with the weakened tear line of said first flap which is furthest from the fold line of said first flap, said second flap weakened tear line including a series of spaced angled slits inclined at an angle to the direction of tear of said second flap weakened tear line, said angled slits of said second flap weakened tear line being staggered from the slits of said substantially aligned weakened tear line, and means providing adhesive attachment between overlying portions of said closure flaps which keeps the overlying portions of said closure flaps in the areas of said substantially aligned weakened tear lines free of adhesive attachment to each other.

27 An easy opening carton including tubularly arranged side panels, and a closure at one end of said panels including closure fiaps foldably connected to said side walls and folded into substantially right angular relation thereto, the closure flaps being folded into a common plane across said end of the carton, a first one of said closure flaps folded to overlie said carton end, said first flap having two weakened tear lines extending thereacross parallel to and spaced from the line of fold of said first flap, each of said two weakened tear lines including a series of spaced slits inclined at an angle to the direction of tear of said weakened tear line, a second closure flap folded to overlie said first flap, said second flap having a single weakened tear line extending thereacross parallel to and spaced from the line of fold of said second flap and in substantial alignment with the weakened tear line of said first fiap which is furthest from the fold line of said first flap, said single weakened tear line including a series of spaced angled slits inclined at an angle to the direction of tear of said single weakened tear line, said angled slits of said single weakened tear line being staggered from the slits of said substantially aligned weakened tear line, means providing adhesive attachment between overlying portions of said closure flaps which lie between the hinge line and the single weakened tear line of said second fiap, means providing adhesive attachment between the overlying portions of said closure fiaps which lie between the weakened tear lines of said first closure flap while at the same time keeping the overlying portions of said closure flaps in the areas of said substantially aligned weakened tear lines free of adhesive attachment to each other.

3. An easy opening carton including tubularly arranged side panels, and a closure at one end of said panels including inner and outer closure flaps foldably connected to said side walls and folded into substantially right angular relation thereto, said inner closure fiaps hingedly connected on opposite pairs of said side panels being folded into a common plane across said end of the carton, a first one of said outer closure flaps hingedly connected to one of said side panels connected between said opposite side panels, said first flap being folded to overlie said inner closure flaps, said first fiap having two weakened tear lines extending thereacross parallel to and spaced from the line of fold connecting said first flap to said one side panel, each of said two weakened tear lines including a series of spaced slits inclined at an angle to said direction of tear, a second one of said outer closure flaps hingedly connected to another of said side panels opposite said first outer flap side panel overlying said first outer flap, said second flap having a single weakened tear line extending thereacross parallel to and spaced from the line of fold connecting said second flap to said another side panel and in substantial alignment with the weakened tear line of said first flap which is positioned furthest from the fold line of said first flap, said single weakened tear line including a series of spaced angled slits inclined at an angle to the direction of tear of said single weakened tear line, said angled slits of said single weakened tear line being staggered from the slits of said substantially aligned weakened tear line, means providing limited adhesive attachment between said inner flaps and said first outer flap, and means providing adhesive attachment between the overlying portions of said outer flaps which lie between the hinge line and the single weakened tear line of said second outer flap while at the same time keeping the overlying portions of said first and second outer flaps in the areas of said substantially aligned weakened tear lines free of adhesive attachment to each other.

4. An easy opening carton including tubularly arranged side panels, and a closure at one end of said panels including inner and outer closure flaps foldably connected to said side walls and folded into substantially right angular relation thereto, said inner closure flaps hingedly connected on opposite pairs of said side panels being folded into a common plane across said end of the carton, a first one of said outer closure flaps hingedly connected to one of said side panels connected between said opposite side panels, said first fiap being folded to completely overlie said inner closure flaps and completely cover said carton end, said first fiap having two weakened tear lines extending thereacross parallel to and spaced from the line of fold connecting said first flap to said one side panel, each of said two weakened tear lines including a tear directing each at a side edge of said first flap for making the initial direction of tear in line with the weakened tear line, a series of spaced slits inclined at an angle to said direction of tear, a second one of said outer closure flaps hingedly connected to another of said side panel opposite said first outer fiap side panel overlying said first outer flap, said second flap having a single weakened tear line extending thereacross parallel to and spaced from the line of fold connecting said second flap to said another side panel and in substantial alignment with the weakened tear line of said first flap which is positioned furthest from the fold line of said first flap, said single weakened tear line including a series of spaced angled slits inclined at an angle to the direction of tear of said single weakened tear line, said angled slits of said single weakened tear line being staggered from the slits of said substantially aligned weakened tear line, means providing adhesive attachment between the overlying portions of said outer flaps which lie between the hinge line and the weakened tear line of said second outer flap, means providing adhesive attachment between the overlying portions of said outer flaps which lie between the weakened tear lines of said first outer flap while at the same time keeping the overlying portions of said first and second outer flaps in the areas of said substantially aligned weakened tear lines free of adhesive attachment to each other, and means providing limited adhesive attachment between said inner flaps and said first outer flap and between the remaining overlying portions of said first and second outer flaps.

5. An easy opening carton including tubularly arranged side panels, and a closure at one end of said panels including inner and outer closure flaps foldably connected to said side walls and folded into substantially right angular relation thereto, the inner closure flaps hingedly connected on opposite pairs of said side panels being folded into a common plane across said end of the carton, a first one of said outer closure flaps hingedly connected to one of said side panels connected between said opposite side panels, said first flap being folded to completely overlie said inner closure flaps, said first flap having two weakened tear lines extending thereacross parallel to and spaced from the line of fold connecting said first flap to said one side panel, each of said two weakened tear lines including a notch with an apex extending into a side edge of said first flap, at least one slit in line with said apex and parallel to the direction of tear of the weakened tear line, a series of spaced slits inclined at an angle to said direction of tear with at least the angled slit which is closest to said in line slit being long enough to be intercepted by a straight line extending along and in the general direction of said in line slit, a second one of said outer closure flaps hingedly connected to an other of said side panels opposite said first outer flap side panel overlying said first outer flap, said second flap having a single weakened tear line extending thereacross parallel to and spaced from the line of fold connecting said second flap to said another side panel and in substantial alignment with the weakened tear line of said first flap which is positioned furthest from the fold line of said first flap, said single weakened tear line including a series of spaced angled slits inclined at an angle to the direction of tear of said single weakened tear line, said angled slits of said single weakened tear line being staggered from the slits of said substantially aligned weakened tear line of said first flap, means providing limited adhesive attachment between the overlying portions of said inner flaps and said first outer fiap and between the overlying portions of said first and second outer flaps which keeps the overlying portions of said first and second outer flaps in the areas of said substantially aligned weakened tear lines free of adhesive attachment to each other.

6. An easy opening carton including tubularly arranged side panels, and a closure at one end of said panels including inner and outer closure flaps foldably connected to said side walls and folded into substantially right angular relation thereto, said inner closure flaps hingedly connected on opposite pairs of said side panels being folded into a common plane across said end of the carton, a first one of said outer closure flaps hingedly connected to one of said side panels connected between said opposite side panels, said first flap being folded to completely overlie said inner closure flaps, said first flap having two weakened tear lines extending thereacross parallel to and spaced from the line of fold connecting said first flap to said one side panel, each of said two weakened tear lines including a notch with an apex extending into a side edge of said first flap, at least one slit in line with said apex and parallel to the direction of tear of the weakened tear line, a series of spaced slits inclined at an angle to said direction of tear with at least the angled slit which is closest to said in line slit being long enough to be intercepted by a straight line extending along and in the general direction of said in line slit, a second one of said outer closure flaps hingedly connected to another of said side panels opposite said first outer flap side panel, said second flap being folded to completely overlie said first outer flap, said second flap having a single weakened tear line extending thereacross parallel to and spaced from the line of fold connecting said second flap to said another side panel and in substantial alignment with the weakened tear line of said first flap which is positioned furthest from the fold line of said first flap, said single weakened tear line including a series of spaced angled slits inclined at an angle to the direction of tear of said single weakened tear line, said angled slits of said single weakened tear line being staggered from the slits of said first flap weakened tear line which is in substantial alignment therewith, means providing adhesive attachment between the overlying portions of said outer flaps which lie between the hingle line and the weakened tear line of said second outer fiap, means providing adhesive attachment between the overlying portions of said outer flaps which lie between the weakened tear lines of said first outer flap while at the same time keeping the overlying portions of said first and second outer flaps in the areas of said substantially aligned weakened tear lines free of adhesive attachment to each other, and means providing limited adhesive attachment between said inner flaps and said first out-er flap and between the remaining overlying portions of said first and second outer flaps.

References (Iited by the Examiner UNITED STATES PATENTS 3,022,931 2/ 1962 Guyer 22951 3,065,896 11/1962 Grapp 22951 3,065,897 11/1962 Grapp 229-51 3,108,735 10/1963 Meyers 22951 3,142,430 7/1964 Meyers 2295l GEORGE O. RALSTON, Primary Examiner.

Claims

1. AN EASY OPENING CARTON INCLUDING TUBULARLY ARRANGED SIDE PANELS, AND CLOSURE AT ONE END OF SAID PANELS INCLUDING CLOSURE AT ONE END OF SAID SIDE WALLS AND FOLDED INTO SUBSTANTIALLY RIGHT ANGULAR RELATION THERETO, THE CLOSURE FLAPS BEING FOLDED INTO A COMMON PLANE ACROSS END OF THE CARTON, A FIRST ONE OF SAID CLOSURE FLAPS FOLDED TO OVERLIE SAID CARTON END, SAID FIRST HAVING TWO WEAKEND TEAR LINES EXTENDING THEREACROSS PARALLEL TO AND SPACED FROM THE LINE OF FOLD OF SAID FIRST FLAP, EACH OF SAID TWO WEAKENED TEAR LINES INCLUDING A SERIES OF SPACED SLITS INCLINED AT AN ANGLE TO THE DIRECTION OF TEAR TO SAID WEAKENED TEAR LINES CLOSURE FLAP FOLDED TO OVERLIE SAID FIRST FLAP, SAID SECOND FLAP HAVING A WEAKENED TEAR LINE EXTENDING THEREACROSS PARALLEL TO AND SPACED FROM THE LINE OF FOLD OF SAID SECOND FLAP AND IN SUBSTANTIAL ALIGNMENT WITH THE WEAKENED TEAR LINE OF SAID FLAT WHICH IS FURTHEST FROM THE FOLD LINE OF SAID FIRST FLAP, SAID SECOND FLAP WEAKENED TEAR LINE INCLUDING A SERIES OF SPACED ANGLED SLITS INCLINED AT AN ANGLE TO THE DIRECTION OF TEAR OF SAID SECOND FLAP WEAKENED TEAR LINE, SAID ANGLED SLITS OF SAID SECOND FLAP WAEKENED TEAR LINE, BEING STAGGERED FROM THE SLITS OF SAID SUBSTANTIALLY ALIGNED WEAKENED TEAR LINE, AND MEANS PROVIDING ADHESIVE ATTACHMENT BETWEEN OVERLYING PORTIONS OF SAID CLOSURE FLAPS WHICH KEEPS THE OVERLYING PORTIONS OF SAID CLOSURE FLAPS IN THE AREAS OF SAID SUBSTANTIALLY ALIGNED WEAKENED TEAR LINES FREE OF ADHESIVE ATTACHEMENT TO EACH OTHER.