US3637131A

US3637131A - Carton with locking means for reclosable cover

Info

Publication number: US3637131A
Application number: US70272A
Authority: US
Inventors: Richard F Gulliver
Original assignee: Gulf States Paper Corp
Current assignee: Gulf States Paper Corp
Priority date: 1970-09-08
Filing date: 1970-09-08
Publication date: 1972-01-25
Anticipated expiration: 1989-01-25

Abstract

A carton formed from a single blank of foldable paperboard or the like having a reclosable cover which is hinged to the upper edge of the rear wall panel of the carton proper or tray portion and provided with front and end apron panels, which, when the cover is closed, respectively overlap the front and end wall panels of the carton. A relatively short horizontal cut, parallel with the upper edges of the front and end walls of the carton, is provided at each upper end corner formed by the front and end walls of the carton. This cut bisects the vertical crease or fold line at each corner, extending into adjacent portions of the front and end walls. That portion of the fold line above the vertical crease which extends to the upper edge of the corner is parallel with but offset towards the body of the front panel from the fold line below the cut. When the end flaps are folded at right angles along these creases, the portions above the horizontal cut are shifted outwardly from the face of the panel and present a detentlike projection, designed to coact with aligned keeper cutouts formed in the cover glue flaps to releasably lock the cover in closed position. The lock is released by applying a firm upward force on the front portion of the cover, causing an upward and inward pressure on the detents, whereby they snap out of their keeper cutouts. Reclosing the cover automatically relocks the same.

Description

United States Patent Gulliver 51 Jan. 25, 1972 [54] CARTON WITH LOCKING MEANS FOR Primary Examiner-Davis T. Moorhead RECLOSABLE COVER Allorney-Raphael Semmes {72] Inventor: Richard F. Gulliver, Waco, Tex. [57] ABSTRACT [73] Assignee: Gulf States Paper Corporation, A carton formed from a single blank of foldable paperboard or Tuscaloosa, Ala. the like having a reclosable cover which is hinged to the upper edge of the rear wall panel of the carton proper or tray portion [22] Filed 1970 and provided with front and end apron panels, which, when [21] Appl. No.: 70,272 the cover is closed, respectively overlap the front and end wall panels of the carton. A relatively short horizontal cut, parallel with the upper edges of the front and end walls of the carton, 52 us. (:1. ..229/36, 229/45, 229/51 TC is provided at each upper end comer formed by the from and [51] 3" "865d 5/22 865d 5/26 end walls of the carton. This cut bisects the vertical crease or Fleld of Search 36, 45, line at each corner, extending i adjacent p i of the front and end walls. That portion of the fold line above the V [56] References cued vertical crease which extends to the upper edge of the corner is parallel with but offset towards the body of the front panel UNITED STATES PATENTS from the fold line below the cut. When the end flaps are folded 2,551,324 5/1951 Frieders et al.. ..228/36 at right angles along these creases, the portions above the 3,010,638 1 1/1 961 Forrer ..229/45 horizontal cut are shifted outwardly from the face of the panel 3,084,842 4/1963 Beech i ..229/35 X and present a detentlike projection, designed to coact with 3,298,595 1/1967 Collura ..229/51 TC aligned keeper cutouts formed in the cover glue flaps to 3,310,223 3/1967 Buttery ..229/5l TC releasably lock the cover in closed position. The lock is 3,326,447 6/1967 Williamson. .....229/45 X released by applying a firm upward force on the front portion 3,338,505 8/1967 Hughes 229/51 TC of the cover, causing an upward and inward pressure on the 3,361,323 1/1968 Adams et al. .....229/45 X detents, whereby they snap out of their keeper cutouts. 3,5 20,468 7/1970 Wieman ..229/45 Reclosing the cover automatically relocks the same.

10 Claims, 11 Drawing Figures PATENTED M25872 3,637,131 MR1 HF &

T l l nuvmmm RICHARD IF. GULLIVER ATTORNEY PATENTFU M25872 3,637,131 SEEK MP 5 8 HNVENTOR RICHARD F. GULLIVER m, @WM

ATTORN EV PATENTEDJANZSEUZ 3,637,131

INVENTOR RICHARD IF. GULLIVER m (RQWZJM ATTOHNIFY CARTON WITH LOCKING MEANS FOR RECLOSABILE COVER BACKGROUND OF THE INVENTION The present invention relates to paperboard cartons having reclosable hinged covers of the type used for packaging edible products, such as donuts, where the cover is frequently opened and reclosed in gaining access to the carton. With cartons of this type, especially those for packaging food items such as donuts, after the cover is initially opened, unless some means is provided for temporarily locking the cover in closed position, unintentional opening frequently occurs, which results in a loss of product moisture and also the accidental spilling of the carton contents.

It is therefore desirable to provide locking means for the cover which will facilitate its easy opening and reclosing as products are removed from the carton and to securely relock the cover numerous times without tearing the same.

SUMMARY OF THE INVENTION It is therefore the primary object of the present invention to provide a carton of this character having locking detents adjacent the upper edges of each forward corner of the carton proper, formed by applying horizontal cut lines to the joining front and end walls of the carton on either side of the vertical corner crease line. By offsetting that portion of each corner vertical crease line extending above the horizontal out line, with respect to the crease line below the out line, that portion of the corner above the out line is automatically projected outwardly from the face of the front wall of the carton when the comer is folded to form a detent. The glue flaps from the cover end aprons which secure the latter to the inner face of the cover front apron panel are cut out to form keepers aligned to receive the detents when the cover is closed.

BRIEF DESCRIPTION OF THE DRAWINGS Referring to the drawings in which numerals of like character designate similar parts throughout the several views:

FIG. 1 is a perspective view showing the erected carton according to one form of the invention with the cover in closed position;

FIG. 2 is a plan view of a single piece of paperboard or the like cut to form a blank for the carton according to one form of the invention;

FIG. 3 is a fragmentary perspective view of one comer of the carton showing the form of locking detent illustrated in FIG. 2;

FIG. 4 is a sectional view taken on line 4-4 of FIG. 1 showing the locking means in operation;

FIG. 5 is a fragmentary perspective view of the same corner of the carton shown from the inside thereof;

FIG. 6 is a fragmentary perspective view showing a modified form of locking device;

FIG. 7 is a fragmentary perspective view showing a further modification of the locking device;

FIG. 8 is still another modified form shown by a perspective of one corner of the carton;

FIG. 9 is a fragmentary perspective view taken from the inside of the cover of the carton shown in FIG. 7;

FIG. 10 is a view of the interior of the cover showing a modified form of glue flap which is folded on itself to provide a keeper for the detent; and

FIG. II is a view showing a still further modification of the glue flap which is formed to provide an inwardly protruding abutment which acts as a keeper for the detent in the tray wall.

DETAILED DESCRIPTION OF THE INVENTION In the drawings, referring first to FIG. 2, the numeral I2 designates the blank proper cut to form the panels and flaps of the carton of the present invention, illustrating one form of locking means. The blank comprises a bottom panel 13 for the tray portion of the carton which is connected along longitudinally extending parallel hinge lines 14 and I5 to front and rear tray wall panels I6 and 17, respectively. The bottom panel I3 is connected at hinge lines 18 to end flaps I9, which, as will later appear, coact with end tray flaps 20 and 2I of the front and rear wall panels I6 and I7, respectively, to form the end walls of the carton tray when the latter is erected. The

end tray flaps

20 and 21 are hingedly connected to the ends of

panels

16 and 17 along continuations of the hinge lines 18 previously referred to, which connect the end flaps 19 to the bottom panel 13.

The cover for the carton tray is generally indicated by the numeral 22 and comprises a top panel 23 which is hingedly connected to the rear tray panel 17 along hinge line 24 which runs parallel with the hinge lines I4 and 15 previously referred to. Along the forward edge of the top panel 23, a front apron panel 25 is hingedly connected along hinge line 26, and each end of this top panel is provided with an end apron panel 27 which is hingedly connected along a further extension of the hinge line 18, each of the end apron panels 27 being provided adjacent the front apron panel 25 with a glue flap 28 hingedly connected along extensions of hinge line 26, whereby, when the carton is erected, the end panels 27 may be secured to the inner surface of the front apron panel 25 at the corners thereof to retain the cover in assembled position.

In the form of the invention here illustrated, a window is formed by opening 29 in adjacent portions of the rear and

top panels

17 and 23 respectively, which may be covered with a transparent sheet 30 glued at its extremities to the panels in well-known manner. Also, any known type of tear strip 31 may be provided on the front apron panel 25 for releasably securing the cover in closed position when the carton is initially packed.

Various conventional means of locking the

end tray flaps

20 and 21 in overlying relation with respect to the bottom end flaps 19 may be employed. In the form of the invention here illustrated, each front wall end tray flap 20 is provided with an irregular out line 32, which, when the end flap is folded inwardly, engages with a locking tab 33 on the corresponding rear panel end flap 21 which overlies. the end flap 20. Also, each end flap 20 is provided along its free top edge with two

parallel cut lines

34 and 35 extending perpendicularly to said free top edge for interlocking with a substantially T-shaped tab 36 cut in the corresponding end flap 21 of the rear tray panel 17. The operation of this feature will be referred to later The essence of the present invention resides in the means for releasably locking the carton cover in closed position. The preferred form of cover locking means is shown in FIGS. 2-5, where it will be seen that a out line 37 37a is cut to intersect the junction of the front tray panel 16 and its end flap 20 parallel with but spaced inwardly from the free edges of the panels. As best seen in FIG. 2, when the blank is formed, this horizontal cut line bisects the vertical crease line 18, and that portion 18a of the crease line which extends outwardly towards the free edge of the panel 16 is offset with respect to the main comer crease line I8 in a direction toward the body of the panel 16. In this form, the longer portion of the cut line 37 lies in the panel 16, while the shorter portion 37a of said out line lies in the end flap 20.

As seen in FIG. 3, when the panels are folded along the crease line 18, the upper portions of the

panels

16 and 20 carrying the offset crease line 18a are caused to protrude forwardly from the face of the front panel I6, forming a projecting detent 18b.

Returning to FIG. 2, the glue flap 2B is provided with a cutout area 38, which, when the carton is erected, is aligned to receive the projecting detent at 18b, as best seen in FIG. 4. The cutout 38 thus acts as a keeper for the detent 18b to lock the cover in closed position. To release this locking means, an upward force is exerted on the front portion of the cover, which, due to certain flexibility in the detent portion 18b of the

panels

16 and 20, located above: the out line 37-37a,

results in an upward and inward pressure on the detent, causing it to snap out of the keeper cutout 38, permitting the opening of the cover. Upon closing the cover, this locking means automatically resumes locked position. It should be noted that the upper portion 18a is always offset with respect to portion 18 in the direction of the wall of the tray portion to which the glue flap-keeper means is adhered.

Various modifications of the basic principle embodied in the forming of the detent previously described may be employed in the manufacture of the carton of the present invention. For example, as shown in FIG. 6, that portion of the vertical crease line 18a above the horizontal out line 3737a may be provided with a notch or the like 180 to provide a weakened crease line. Similarly, weakened crease lines 18c are provided at the opposite bases of the protruding detent 18b. In this form of the invention, the longer portion 37 of the horizontal out line is located in the front panel 16, while the shorter portion 37a thereof is in the end tray flap 20.

In the modification shown in FIG. 7, the notched or weakened portion of the cut line 18a is eliminated and is used only at the opposite bases of the detent 18b, as shown at 180 in this figure. Here, it will be noted that the arrangement is such that the detent 18b protrudes from the face of the end flap of the carton as distinguished from the front panel 16, and the glue flap 28 is hinged to the front apron panel of the cover and secures the latter to the end apron panel 27 thereof for engagement by the detent 18b.

The modification shown in FIG. 8 is generally similar to that shown in FIG. 7, with the exception that the long portion 37 of the horizontal out line is located in the end tray flap 20, while the short portion 37a thereof is located in the front wall panel 16.

A modified form of glue flap for securing the comers of adjacent cover apron panels is shown in FIG. 10. Here, it will be seen that the glue flap 28 is hingedly connected to the end apron flap 27, and its main body portion at the hinge line 26 is substantially the same depth as the

apron panels

25 and 27. This modified flap 28 is provided with a vertically projecting portion 280 of less depth than the main body portion of the flap 28, as shown in dotted lines in FIG. 10. This extended por tion 28a of the flap is adapted to be folded upon itself on hinge line 28b, and, being of less depth than the body portion of the flap 28, its free edge 38a forms an abutment which acts as a keeper for the detent formed in the upper edge of the carton tray portion.

It will be obvious that this type of folding glue flap may be hinged to the end apron panel 27 as shown for securing the end apron to the front apron panel 25, or it may be attached and hinged to the front apron panel 25 and glued to the end apron panel 27. The location of this glue flap will depend upon the particular location and direction of protrusion of the detent formed in the tray portion so that the abutment 380 will serve its desired locking function.

In erecting the blank shown in FIG. 2 to the form shown in FIG. 1, the front and

rear wall panels

16 and 17 of the tray portion are respectively folded inwardly with respect to the bottom panel 13 along their

hinge lines

14 and 15. The end flaps 19 of the bottom wall 13 are folded upwardly along hinge lines 18, and the front panel end flaps 20 are folded to overlie flaps 19, after which the rear end flaps 21 are folded to overlie end flaps 20, as shown in FIG. 3. The locking tab and cut lines of the end flaps 20 and 21, which actually form no part of the present invention, are then interlocked as shown in FIG. 3 to retain the end walls in assembled position.

Also, as shown in FIGS. 1 and 4, the top cover panel 23 is folded along its hinge line 24, and the cover end apron panels 27 are folded along their hinge lines 18. The glue flaps 28 are folded along their hinge lines 26, so that when the front apron panel 25 is folded along its hinge line 26, it will overlie the glue flaps 28 which are then secured by suitable adhesive to the inner face of the front apron panel 25.

When the erected carton is filled with its product, the cover 22 is initially sealed by adhering the conventional tear strip 31 to the outer face of the front wall panel 16 of the carton so as to guard the contents against deterioration. In opening the carton, the tear strip 31 is removed, but the cover 22 remains in closed position due to the locking engagement of the detents 18b with the edge of the cutout portion of the glue flap 28, as shown in FIG. 4. In order to release this latter locking device or detent, upward pressure is applied to the front apron panel 25 of the cover, which, due to the engagement of the flexible detent 18b with the keeper cutouts 38 of the glue flaps 28, results in an upward and inward force on the detents. This force causes said detents to snap out of their keeper cutouts, which releases them from their locked condition. The cover can then be readily opened by hinging on its hinge line 24, and when it is reclosed, the detents 18b reengage the cutouts of the glue flaps 28. Thus, the cover can be opened and closed numerous times and still retain the freshness of the contained product.

A still further modification of the glue flap is shown in FIG. 11, where the glue flap is designed to provide a protruding keeper which coacts with the main detent in the carton tray wall. In this modification, the normal glue flap hinge line 26 is offset as at 26a at its upper end in thedirection of the front apron panel 25. A out line 40 is provided in the body of the glue flap 28 and extends into the body of the end apron panel 27, as at 40a, bisecting portions 26 and 26a of the glue flap hinge line. Upon hinging the glue flap on the hinge lines 26- 26a for adhesion to the inner face of the front apron panel 25, the offset portion 260 causes the portion of the glue flap below the out line 4040a to protrude inwardly from the inner face of the front apron panel 25, thus forming a protruding abutment 40b.

When the cover is closed and the front apron panel 25 overlaps the front tray panel 16, the protrusion 40b is engaged by the detent 18b of the tray and locks the cover in closed position. With this form, an upward force on the front apron panel 25 causes the release of the detent.

It will thus be seen that the present invention provides a readily operable locking means for hinged carton covers, which is particularly important in cartons of the type for containing food products, which require frequent opening and closing in removing products from the carton. Also, one of the important features of the present invention resides in the fact that the entire carton, cover and coacting locking elements are formed from a single blank without requiring additional blank areas. In other words, the locking detents are formed from the usual front wall of the carton, and the cutout keeper areas for receiving the detents are provided entirely within the usual glue flaps 28.

From the foregoing, it is believed that the invention may be readily understood by those skilled in the art without further description, it being borne in mind that numerous changes may be made in the details disclosed without departing from the spirit of the invention.

Iclaim:

1. In a carton having a tray portion including flexible front, rear and end walls connected along vertical crease lines, and a reclosable cover with a depending apron panel on at least one edge thereof which is adapted to overlap the upper edge of a corresponding wall of said tray portion, releasable locking means for retaining said cover in closed position, comprising a protruding detent formed by adjoining upper portions of the walls at a corner of said tray portion, the upper portion of said crease line at the junction of said tray walls at said corner being laterally offset, a horizontal out line in the adjoining tray walls at said comer, bisecting said vertical crease line at the inner extremity of the offset portion thereof and defining the lower edge of said detent, whereby, when said adjoining tray walls are initially folded in the erection of said carton, the offset portion of said crease line causes said detent to flexibly protrude at said corner, and keeper means on the depending cover apron panel adjacent said corner aligned to engage said detent, the flexibility of said detent permitting its release from said keeper mans upon the application of manual upward force on said overlapping cover apron panel.

2. In a carton of paperboard or the like including a tray portion having hinged front, rear and end walls and a cover portion having at least front and end hinged apron panels adapted to overlap the front and end walls of said tray portion when the cover portion is closed, said end apron panels being connected to said front apron panel by hinged glue flaps integral with one of said apron panels and overlapping the inner face of a right angularly adjacent apron panel, means for releasably locking said cover portion in closed position, comprising at least one detent formed at a corner of said tray portion by providing the hinge line connecting said front and end tray walls at said comer with an offset portion which extends to the free horizontal edges of said front and end tray walls, a horizontal cut line at the junction of said front and end walls, bisecting said last-named hinge line at the inner terminus of the offset portion thereof, whereby, when said walls are folded on said hinge line, the portions of said front and end walls connected by said offset portion of said hinge line protrude outwardly to form a detent, at least one of said glue flaps being formed to provide an abutment, which, when said cover is closed, is aligned to engage said protruding detent, acting as a keeper therefore, said detent being releasable from said abutment by applying upward pressure on the cover apron panel to which the glue flap is adhered, causing the detent to snap out of contact with said abutment.

3. The invention as claimed in claim ll, wherein said detent is provided with weakened vertical hinge lines at predetermined points to facilitate its flexibility.

d. The invention as claimed in claim 1, wherein said detent is provided with weakened vertical hinge lines at its horizontal extremities to facilitate its flexibility.

5. The invention as claimed in claim 4, wherein said detent is provided with weakened hinge lines at its horizontal extremities and intermediate said horizontal extremities to facilitate its flexibility.

6. The invention as claimed in claim I, wherein said horizontal cut line extends a greater distance from one corner into one tray wall than into the adjoining wall.

7. The invention as claimed in claim 1, wherein the offset portion of said vertical crease line is offset toward the body of the tray wall overlapped by the cover apron having said keeper means, whereby the detent projects outwardly from said tray wall.

'8. The invention as claimed in claim 2, wherein said keeper means is formed by a cutout area in one of said glue flaps.

9. The invention as claimed in claim 2, wherein said one of said glue flaps is provided with a vertical extension of less depth than that of the glue flap proper, said extension being folded upon the glue flap proper, whereby its free extremity forms a keeper abutment for engagement by said detent.

1 .0, The invention as claimed in claim 2, wherein the hinge line of said one of said glue flaps is offset at its upper extremity, and a horizontal out line in said glue flap bisecting said hinge line at the point of its offset and extending into the apron panel to which the glue flap is hinged, whereby, when said glue flap is folded on its hinge line, that portion of said flap below said horizontal out line protrudes inwardly to form an abutment for engagement by the detent of said tray portion.

Claims

1. In a carton having a tray portion including flexible front, rear and end walls connected along vertical crease lines, and a reclosable cover with a depending apron panel on at least one edge thereof which is adapted to overlap the upper edge of a corresponding wall of said tray portion, releasable locking means for retaining said cover in closed position, comprising a protruding detent formed by adjoining upper portions of the walls at a corner of said tray portion, the upper portion of said crease line at the junction of said tray walls at said corner being laterally offset, a horizontal cut line in the adjoining tray walls at said corner, bisecting said vertical crease line at the inner extremity of the offset portion thereof and defining the lower edge of said detent, whereby, when said adjoining tray walls are initially folded in the erection of said carton, the offset portion of said crease line causes said detent to flexibly protrude at said corner, and keeper means on the depending cover apron panel adjacent said corner aligned to engage said detent, the flexibility of said detent permitting its release from said keeper means upon the application of manual upward force on said overlapping cover apron panel.

2. In a carton of paperboard or the like including a tray portion having hinged front, rear and end walls and a cover portion having at least front and end hinged apron panels adapted to overlap the front and end walls of said tray portion when the cover portion is closed, said end apron panels being connected to said front apron panel by hinged glue flaps integral with one of said apron panels and overlapping the inner face of a right angularly adjacent apron panel, means for releasably locking said cover portion in closed position, comprising at least one detent formed at a corner of said tray portion by providing the hinge line connecting said front and end tray walls at said corner with an offset portion which extends to the free horizontal edges of said front and end tray walls, a horizontal cut line at the junction of said front and end walls, bisecting said last-named hinge line at the inner terminus of the offset portion thereof, whereby, when said walls are folded on said hinge line, the portions of said front and end walls connected by said offset portion of said hinge line protrude outwardly to form a detent, at least one Of said glue flaps being formed to provide an abutment, which, when said cover is closed, is aligned to engage said protruding detent, acting as a keeper therefore, said detent being releasable from said abutment by applying upward pressure on the cover apron panel to which the glue flap is adhered, causing the detent to snap out of contact with said abutment.

3. The invention as claimed in claim 1, wherein said detent is provided with weakened vertical hinge lines at predetermined points to facilitate its flexibility.

4. The invention as claimed in claim 1, wherein said detent is provided with weakened vertical hinge lines at its horizontal extremities to facilitate its flexibility.

6. The invention as claimed in claim 1, wherein said horizontal cut line extends a greater distance from one corner into one tray wall than into the adjoining wall.

8. The invention as claimed in claim 2, wherein said keeper means is formed by a cutout area in one of said glue flaps.

10. The invention as claimed in claim 2, wherein the hinge line of said one of said glue flaps is offset at its upper extremity, and a horizontal cut line in said glue flap bisecting said hinge line at the point of its offset and extending into the apron panel to which the glue flap is hinged, whereby, when said glue flap is folded on its hinge line, that portion of said flap below said horizontal cut line protrudes inwardly to form an abutment for engagement by the detent of said tray portion.