US2544565A - Collapsible carton - Google Patents

Description

March 6, 1951 L. H. PHILLIPS 2,544,565

COLLAPSIBLE CARTON Filed Oct. 28, 1949 l: I 5L. fnuenfm J2 .6 CZLUIEILC'CHPAZIZZZEPS Patented Mar. 6, 1951 UNITED STATES PATENT OFFICE OOLLAPSIBLE CARTON Lawrence H. Phillips, Chattanooga, Tenn, as-

signor to O. 8. Andrew: Company, Chattanooga Team, a corporation of Tennessee Application October 28, 1949, Serial No. 124,178

3 Claims. (Cl. 229-33) paperboard or similar foldable sheet material,

the cover and the tray being each provided with cooperating locking means for securing them in closed position after the contents have been loaded in the tray portion.

Among the objects of the invention are to provide compactly collapsible tray and cover sections which can be quickly and conveniently set up by the simple expedient of raising the front, side and rear walls of the tray to upright position with respect to the bottom of the tray and swinging the side and front walls of the cover portion to a position at right angles to the cover, and to form an extended part or parts on one of the sections interlocking with apertures or recesses on the other section whereby to retain the cover and tray interlocked after being filled and with the cover brought to closing position.

Another object is to provide means for retaining the side walls in approximately vertical position after they have been raised from their collapsed position in which portions of the side walls lie flat againstthe bottom wall.

Other objects and advantages of the present invention will become apparent from the following specification and in the claims appended thereto.

In the drawings, illustrating a preferred embodiment of the invention- Fig. l is a perspective view, illustrating the carton in an open condition ready to receive contents;

Fig. 2 is a fragmentary top view of the tray, illustrating the means for retaining the side walls in approximately vertical position;

Fig. 3 is a fragmentary sectional view along line 3-3 of Fig. 2;

Fig. 4 is a fragmentary side view of the carton in partially opened condition, and with certain portions broken away;

Fig. 5 is a fragmentary side view, illustrating the tray and cover in locked position;

Fig. 6 is a fragmentary sectional view of the cover portion, illustrating one of the cover locking elements; and

Fig. 7 is a fragmentary plan view illustrating the construction of the front corner portion of the carton blank.

In general the carton of the present invention in its preferred form comprises a tray with front, rear and side walls integral with the tray bottom and a cover integral with the rear wall of the tray having front and side walls or flanges. The front and rear walls of the tray are each arranged to fold inwardly to lie flat on the tray bottom and the two side walls are diagonally creased so as to be foldable in part upon the tray bottom and at the same time remain se-.

cured at their ends to the front and rear walls by means of suitable corner flaps connecting the sides to such walls. The side flanges of the cover are also diagonally creased and secured to the front wall of the cover by corner flaps thus enabling the side flanges or walls of the cover to be collapsed in part to lie flat against the under side of the cover. The cover and its flanges, when collapsed, are adapted to lie substantially flat against portions of the bottom of the tray and its attached collapsed side walls and front wall. A locking detent is preferably formed as a rigid extended portion at each lower front corner of the tray, such detents being adapted to be received in suitable openings formed at the corners of the cover section along the line of juncture of the front and side walls of the tray section.

Referring to the drawings. the carton is preferably in the form of a one-piece blank and comprises a bottom tray portion indicated generally at I 0 and a cover portion indicated generally at H. The tray portion comprises a bottom panel l2, front and-rear walls l3 and i4 and side walls l5, IS. The cover portion comprises a main panel IT, a front wall l8 and side walls l9, l9. Crease lines 20 and 2| are impressed in the blank to separate the front wall i3 and rear wall M, respectively, from the bottom panel l2, and crease lines 22 and 23 are impressed in the blank to separate the rear wall and the front wall 18 of the cover from the cover panel ll. Crease lines 25, 25 are impressed longitudinally of the blank to separate the tray side walls l5, I5 from the bottom panel l2, and crease lines 26, 26 are impressed in alignment with the crease lines 25, 25 to separate the cover side walls l9, l9 from the cover panel H.

The side walls l5, 15 of the tray are secured to the rear wall M by means of corner flaps 21, 21 carried on the rear ends of the side walls and are separated therefrom by crease lines 2la, 2la which are extensions of the crease line 2|. For the purpose of connectingthe side walls l5, l5 to the front wall l3 the ends of wall I3 are provided with corner flaps 28, 28 preferably of rectangular shape. These flaps are defined from the front wall I3 by means of crease lines 25a, 25a forming extensions of crease lines 25, 25.

In order to make the tray portion collapsible diagonal crease lines 29, 29 are impressed in the walls I5 and extend from the intersecting point of crease lines 2I and at an angle of approximately 45 to the outer edge of each of the walls I5. There is thus defined between the crease lines 2Ia and 29 a rear triangular portion 30 in each side wall. Additional diagonal crease lines 3|, 3| are impressed in the side walls I5 which extend from the intersection of the crease lines 20 and 25 at an angle of approximately 45 to the outer edge of each side wall. There is thus defined between the crease line 3I and the forward edge of the side wall I5 a forward triangular portion 32 in each side wall.

The corner flaps 21, 21 are preferably secured as by means of an adhesive to the inside surface of the rear wall I4 and the corner flaps 28, 28 are preferably secured to the inner side of the side wall I5 only within the area of the forward triangular portions 32, 32. Due to the arrangement just described the central portion of each wall I5, I5 may be folded down against the bottom panel I2 and, simultaneously with such movement, the rear and forward triangular portions of the walls I5, I5 will be folded over against the central portion of such Walls and the front and rear walls will be folded inwardly and downwardly against the triangular portions in a position overlying the bottom panel I2. In such collapsing the corner flaps 28, 28 will be so moved that they will come to rest flat against the inner surface of the front wall I3.

It is to be understood that the carton, in practice, will be constructed in a series of gluing operations in which the carton will be completely manufactured in a collapsed condition and that it will not ordinarily be necessary for the carton to be collapsed after it has once been set up for use.

The side walls I9, I 9 of the cover portion are preferably secured to the cover front wall IB by means of a corner flap 33 carried by the forward end of each side wall I 9. Each flap 33 is hingedly joined to side wall I9 along the crease line 23a which forms an extension of the crease line 23 between the top panel I! and the front wall I8. In order to enable the cover portion of the carton to be formed in collapsed condition a crease line 34 will be impressed in each cover side wall I9 along the diagonal line extending from the intersection of the crease lines 23 and 26 to the outer edge of the cover side wall I9, thus defining a forward triangular portion 35 in the forwaid edge oi each side wall I9.

The cover portion of the carton, due to the arrangement just described, may be manufactured in collapsed condition by having the main portions of the cover side walls I9, I9 folded flat against the panel II with the forward triangular portions 35, 35 folded over against such main portions of the side walls and with the front wall I8 brought to a position overlying the triangular portions and the main panel I1.

Cooperating parts are provided on the tray and the cover for locking the cover in place on the tray after it has been filled with contents. For this purpose a projecting part is provided at one or both front corners of the tray and a recess or opening is provided at a corresponding front corner or both front corners of the cover for receiving such projecting part thus to hold the cover in alignment with the crease line 20.

4 locked in closed position upon the tray. 'In the preferred form of the invention the forward triangular portion 32 of the tray side wall is formed with a projecting tab or detent 31 which is of such size as to extend forwardly slightly beyond .the plane of the front wall I3 after-the front wall has been connected to the side walls I5, I5 by securing each comer flap 28 to the triangular portion 32, as previously described. The lower edge 38 of the detent 31 is preferably out along a line which is approximately parallel to the bottom wall I2 to provide a locking edge. The upper edge portion 39 of the detent is preferably out along an inclined line for a purpose presently to be described.

The edge of the forward triangular portion 32,

lying above the detent 31, as indicated at 40, is

preferably cut back out of alignment with the front edge of the triangular portion which lies below the detent. The edge portion 40 is also preferably inclined rearwardly at a slight angle to a line which is normal to the bottom panel I 2. The cutting of the edge 40 as just described permits of a relationship with the front corner of the tray wherein the edge 40 will be spaced rearwardly of such front corner.

The cover portion is provided, as herein illustrated, with a detent receiving opening 4| preferably formed adjacent the crease line 23a which constitutes the hinge between the front cover wall I8 and the side wall I9. While the opening 4| may be formed in different manners it is preferably formed by making a U-shaped slit with the ends of the slit terminating approximately on the crease line. The crease line 23a is preferably interrupted between the ends of the U-shaped slit thus providing a portion 42 which remains in the plane of the triangular portion 35. Thus, when the corner flap 33 is moved at an angle to its connected triangular portion 35, the portion 42 will remain in the plane of the triangular portion 35 and the detent receiving opening 4| will be made effective and ready'to receive the detent 31.

Means are provided for maintaining the tray in set-up condition. For this purpose one or more abutment portions in the form of raised or embossed lines or nubs 44 are indented inwardly of the bottom panel I2 to form upwardly projecting portions in a position to be engaged by the lower edge of each corner flap 28. As indicated in Fig. 7, the detent 31 is cut from stock that would otherwise be a part of the corner flap 28 if the lower edge of such flap was extended outwardly Advantage is taken of this feature by continuing the cut of the lower edge of the corner flap 28 outwardly upon the offset line necessitated by the provision of the detent 31. When the corner flap 28 is secured to the forward triangular portion 32 of the tray side wall the securing of these parts is preferably done in such manner that the front wall I3 will be disposed at a slight angle inwardly of a line which is normal to the bottom panel I2. By this arrangement the hinge lines for the corner flaps 28 are tilted rearwardly of the tray and the lower free comer portions of each of the corner flaps are caused to drag along the inner surface of the bottom panel I2 as soon as such outer free corner portions approach a position adjacent the crease lines 25 between the bottom panel and its attached side walls. The

embossed lines or nubs 44 are impressed in the bottom panel at such position so as to be engaged by the outer free edges of the comer flaps 28 as they drag along the surface of the bottom panel when the box is opened and in this way the embossed lines or nubs 44 tend to resist retrogressive movement of the fiaps 28 once the flaps have been moved to a position approximately flat against the walls l5.

In the use of the carton of the present invention it will be completely formed by suitable gluing mechanism in collapsed form in a manner which is well known, and in such condition will be delivered to the packer. When the carton is ready to be filled it is usually opened by automatic high speed machinery which delivers the carton to filling mechanism immediately after it has been opened. The presence of the embossed lines or nubs 44 tends to assure that the tray, after being opened, will remain in opened condition until the carton reaches the filling mechanism. After the tray part has been filled with the desired contents, usually food products which are later to be quick frozen, the presence of such contents in the tray will serve to square up the tray and maintain the side walls I5, in straight condition.

After filling the tray the cover portion is expanded and will be swung down over the filled tray. As the cover portion approaches its final position the edge of the front wall will slide over the inclined edge 39 of the detents and thereafter the detents 37 will be received into the detent-receiving openings 4i, 4! and the parts will come to rest with the straight portion 38 of each detent in engagement with the lower edge of each opening 4 l. The detent 31 is made sumciently short so that it will not extend appreciably beyond the plane of the outer surface of 1 the cover front wall 18. Likewise the U-shaped slit which releases the portion 42 will be made sufficiently small so that the part 42 also will not extend appreciably beyond the plane of the outer surface of the front wall l8. By this construction the locking parts will not be in any way unsightly and will not interfere with mechanical wrapping mechanism if the filled and closed cartons are to be enclosed within a wrapper.

While the present description sets forth a preferred embodiment of the invention, certain changes may be made in the construction without departing from the spirit of the invention, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate .the scope of the invention.

I claim:

1. A paperboard carton including a tray and a cover of substantially the same depth hinged along the rear edges thereof, the tray comprising a bottom panel with a front wall, rear wall and end walls substantially perpendicular thereto extending from the edges thereof, the front end edge of each of the end walls adjacent the front wall being offset inwardly of the plane of said front wall a substantial distance and having a projection extending outwardly of the plane of the front wall, the cover comprising a top panel with front and end walls corresponding to said tray walls adapted to extend about the tray walls when the cover is disposed over the tray, the cover wall corresponding to said front wall of the tray having an opening therein at each end thereof adapted to receive said projection upon disposition of the cover over the tray to prevent separation thereof, the offset relation of said end edge affording positive clearance between the outer corner formed by said tray walls and the inner corner defined by said cover walls, whereby jamming of the cover in closing movement over the tray is prevented and positive locking engagement of the projection in the opening is facilitated.

2. A paperboard carton as set forth in claim 1 wherein the front tray wall is inclined inwardly at slightly less than a right angle to the hollow panel to facilitate disposition of the cover over the tray.

3. A paperboard carton including a tray and a cover of substantially the same depth, hinged along the rear edges thereof, the tray comprising a bottom panel with a front wall, a rear wall, and side walls substantially perpendicular thereto extending from the edges thereof, the front end edge of each of the side walls adjacent the front wall being offset inwardly of the plane of the said front wall a substantial distance, projections extending outwardly of the planes of the walls at the front corners, the cover comprising a top panel with front and side walls corresponding to said tray walls adapted to extend about the tray walls when the cover is disposed over the tray, the cover walls having openings therein at the front corners adapted to receive said projections upon disposition of the cover over the tray to prevent separation thereof, the offsetrelation of said end edges affording positive clearance between the outer corners formed by said tray walls and the inner corners defined by said cover walls, whereby jamming of the cover in closing movement over the tray is prevented and positive locking engagement of the projections in the openings is facilitated.

LAWRENCE H. PHILLIPS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS

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