Carton Opening Means

Abstract

A pair of opposed flaps are provided in closure flaps connected to a panel of a paste end carton to permit the passage of retaining fingers while squaring up the cartons from a flat folded state as the cartons are withdrawn from a hopper.

Description

This invention relates to an improvement in carton opening means and deals particularly with a construction useful in improving carton tightness.

BACKGROUND OF THE INVENTION

In the opening of flat folded cartons, usually of the "paste end" type, the flat folded cartons are usually placed in face contact in a suitable hopper. The cartons are urged toward the discharge end of the hopper by suitable means. This may be some sort of carton follower which urges the stack of cartons toward the open end of the hopper, or the hopper may be supported on angle which is either vertical or sufficiently inclined so that the stack of cartons will slide toward the open end of the hopper by gravity. In order to open the cartons from their flat state, suction cups are often used to pull the foremost carton from the stack and to direct it between suitable guides capable of folding it into tubular rectangular form.

In removing the flat cartons from the hopper, suction cups are often used to pull the foremost carton from the stack, these suction cups often tend to bow both sides of the carton instead of the front side only, causing the cartons to jam rather than to open. In order to prevent this from occurring, generally U-shaped notches are often cut into the closure flaps of one of the foremost panels, and fingers are provided in alignment with these notches; these fingers engaging one of the closure flaps on the rear side of the carton rather than the forward side thereof. As a result, when the suction cups engage the front side of the foremost carton, the rear side of the carton is slightly retarded to overcome the tendency of the rear side of the carton to bow with the forward side thereof as the front of the carton is engaged by the suction cups. These fingers are usually adjustably fixed in position, and as the carton squares up, the closure flaps on the rear side of the carton may merely flex sufficiently to pass by the restraining fingers.

In closing the cartons, the notched flaps of the cartons are usually folded beneath an opposing flap in order to conceal the notch when the cartons are closed. When the cartons are rectangular rather than square, the notches are usually formed in the closure flaps of one of the wider panels as this simplifies the opening operation. The notches thus usually occur between the ends of the closure flaps on the side walls of the carton which are first folded into coplanar relation before the wider flaps are folded. This results in an opening in the flap structure which simplifies the sifting of the carton contents. It is this problem which the present structure is designed to eliminate.

SUMMARY OF THE INVENTION

I have found that by substituting a foldable tab structure for the notches normally used, an improved carton structure may result. In the present structure, the U-shaped or generally semi-circular notches are eliminated and in their place, the closure flaps on the foremost walls are cut to provide a pair of opposed tabs foldably connected to the flaps in such a manner as to provide a pair of end abutting doors. This is accomplished by providing a cut line at right angles to the end of the closure flaps midway between the side edges thereof, and providing a second cut line intersecting the inner end of the first cut line and extending generally parallel to the end edge of the closure flaps in question. This provides a pair of end abutting tabs or doors which may be folded out of the plane of the flaps in which they are formed. The cut lines are arranged so that the carton retaining fingers engage the center portions of the flaps so that when the carton panels on the forward side of the foremost carton of the stack are engaged by suction cups, the retaining fingers may merely fold the tabs apart sufficiently to allow the retaining fingers to pass therebetween, and to engage the opposite flap on the rear side of this carton. As the cartons are squared up, filled and closed, the normal resiliency of the paperboard tends to return the tabs into edge abutting relation, eliminating the opening through this flap which was previously caused by the notch formed therein. The adhesive on the under side of outer flap adheres pin or finger opening to outer flap which further improves carton tightness.

These and other objects and novel fetures of the present invention will be more clearly and fully set forth in the following Specification and Claims .

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic perspective view of a carton in squared up position forwardly of a stack of flat folded cartons.

FIG. 2 is a diagrammatic top plan view of a series of flat folded cartons in a hopper showing the front carton in partially opened position as it is engaged by the suction cups.

FIG. 3 diagrammatically illustrates the foremost carton as it is being opened up, and showing diagrammatically a pocket into which the squared up carton is to be drawn.

FIG. 4 is a perspective view of an end of the carton after three of the four flaps have been closed.

FIG. 5 is a diagrammatic view of the blank illustrating the construction thereof.

FIG. 6 is an enlarged diagrammatic view of the tabs or doors 32.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following description, the depiction of the apparatus for squaring up the carton is merely diagrammatic. Apparatuses for accomplishing this operation are well known, and the apparatus varies with different manufacturers. The illustration is designed merely to indicate the purpose of the carton construction which is the subject of the present invention.

The carton A illustrated in FIG. 5 of the drawing is generally conventional in design. The carton includes a front panel 10, a side wall panel 11, a rear wall panel 12, and a second side wall panel 13. A glue flap 14 is hinged to one end of the blank as to the front panel 10. The various panels and the glue flap are connected by parallel fold lines 15.

Top closure flaps 16, 17, 19 and 20 are foldably connected to the upper edge of the wall panels 10, 11, 12 and 13 respctively along a fold line 21. Similar closure flaps 22, 23, 24 and 25 are foldably connected to the lower edges of the panels 10, 11, 12 and 13 along a fold line 26. The fold lines 21 and 26 are parallel and at right angles to the fold lines 15. The terms "upper edge" and "lower edge" are merely for simplicity of description, as the wall panels may extend horizontally or vertically.

Cut lines 27 may extend into the closure flaps 16 and 22 in right angular relation to the upper and lower edges 29 and 30 of the blank. These cut lines 27 extend only a short distance into the flaps terminating in spaced relation to the fold lines 21 and 26. Second cut lines 31 intersect the inner ends of the cut lines 27 and extend parallel to the fold lines 21 and 26. The cut lines 31 normally extend an equal distance on opposite side of the cut lines 27 in order to provide a pair of tabs or doors 32 of rectangular form between the cut lines 31 and the adjoining blank edge 29 or 30. Actually, it is not necessary that the cut lines 31 extend parallel to the fold lines 21 and 26 as they could be V-shaped in form or rounded in form as long as they form opposed end abutting tabs or doors. If desired, the ends of the cut lines 30 may be connected to the edges 29 or 30 of the blank by parallel fold lines 33. Whether or not the fold lines 33 are employed depends upon the flexibility of the paperboard, as if the paperboard is sufficiently flexible, the tabs will flex when engaged to produce the same result. Whether or not the fold lines 33 are used also depends upon the length of the cut lines 31, as any increase in the length of these cuts lines correspondingly increases the flexibility of the tabs 32.

To diagrammatically illustrate the purpose of the construction described, FIGS. 1 to 3 disclose a hopper which is indicated generally by the letter B. The hopper includes sides 34 between which the carton blanks A are stacked. Obviously, in the arrangement illustrated, the hopper must include a bottom support such as 35. A retaining pin 36 is supported at the forward end of the hopper projecting upwardly from the end of the bottom support 35. A similar retaining pin 37 projects downwardly from a support 39 which is connected to the hopper in any suitable manner, not illustrated in the drawings. These pins are designed to engage the flaps 16 and 22 and extend along the cut lines 27, the pins 36 and 37 terminating short of the cut lines 31.

Suction cups 40 are mounted upon tubular supports 41 normally mounted on the ends of arms 42 pivotally supported at a remote point 43. Means are provided to oscillate the arms 42 in a manner to move the suction cups 40 toward and away from the stack of flat folded cartons A in the hopper. As the suction cups 40 are oscillated away from the hopper, the carton blanks are squared up by means of suitable guides 44 and 45. As the cartons reach rectangular form, they are normally engaged in pockets 45 mounted upon a conveyor 46. When the cartons are drawn into the pockets 45, the suction cups 40 are disengaged from the carton blanks by releasing the suction, and the cartons are carried to the closing and filling apparatus.

As previously stated, the only purpose of the description of the apparatus is to show the purpose of the carton structure. As indicated in FIG. 2, as the foremost carton blank A is engaged by the suction cups 40, the retaining pins 36 and 37 flex the tabs or doors 33, permitting the front wall of the carton to be drawn forwardly while the retaining pins still engage the flaps on the rear side of the carton to restrain it in place until the cartons are at least partially open. Continued movement of the carton will cause the retaining pins to flex the rear flaps 19 and 24 sufficiently to allow the carton to pass the retaining pins. The retaining pins will not pass the rear flaps until the carton is opened sufficiently to insure the proper squaring of the tubular cartons.

In accordance with the Patent Statutes, I have described the principles of construction and operation of my improvement in CARTON OPENING MEANS; while I have endeabored to set forth the best embodiment thereof, I desire to have it understood that obvious changes may be made within the scope of the following Claims without departing from the spirit of my invention.

Claims

I claim:

1. A carton comprising:

front and rear panels foldably connected by side panels,

front and rear closure flaps hingedly connected to an edge of said front and rear panels respectively and adapted to fold into superimposed relation,

said front panel closure flap including a first slit extending from the edge of said front panel closure flap toward the line of hinge connecting the same to said front panel and perpendicular thereto, said slit terminating short of the line of hinge,

a second slit extending generally parallel to said line of hinge and intersecting the end of said first slit, whereby the area between said second slit and said edge of said front panel closure flap froms a pair of end abutting tabs.

2. The structure of claim 1 and including lines of fold parallel to said first slit and connecting the ends of said second slit to said edge of said front panels closure flap.

3. The structure of claim 1 and in which said second slit extends a substantially equal distance on either side of said first slit.

4. The structure of claim 2 and in which said second slit extends a substantially equal distance on either side of said first slit.

5. A carton for use in combination with a carton hopper adapted to contain a series of flat folded cartons in face contact, a pair of lugs engaging opposite ends of the foremost carton to retain the cartons in the hopper, and suction cup means movably supported toward and away from the hopper and engageable with the front surface of the foremost carton in the hopper to remove the same from the hopper, the carton including:

a front panel and a foldably connected side wall in coplanar relation in flat condition of said carton, and a rear panel and a foldably connected second side wall in coplanar relation in flat condition of said carton, said front panel being foldably connected to, and in face contact with, said second side wall and said rear panel being foldably connected to, and lying rearwardly of, said first side wall panel,

closure flaps hingedly connected to the opposite ends of said front panel, said rear panel, and said first and second side walls along hinge lines,

the front closure flaps hingedly connected to front panel having lug receiving gates therein in the ends of said front closure flaps comprising:

first slits extending into the end edges of said front closure flaps in aligned relation intermediate the parallel sides of said front closure flaps, said slits extending normal to the front closure flap ends and terminating short of the lines of hinge connecting said front closure flap to said front panel,

second slits centrally intersecting the ends of said first slits most remote from the end edges of said front closure flaps, said second slits extending generally parallel to the lines of hinge connecting said front closure flaps to said front panel, whereby

the area between said second slits and the adjacent end edges of said front closure flaps providing opposed end abutting tabs foldable out of the plane of said front closure flaps so that the lugs may pass therebetween in the squaring of the carton from its flat folded condition.

6. The structure of claim 5 and including parallel fold lines connecting the ends of said second slit to the end edges of said front closure flaps said fold lines being parallel to said first slit.