US3432090A - Self-locking box - Google Patents

Description

March 11, 1969 K. ENGEL SELF-LOCKING BQX Filed June 12, 1967 INVENTOR Karl EN United States Patent 3,432,090 SELF-LOCKING BOX Karl Engel, Pierrefonds, Quebec, Canada, assignor to Domtar Limited, Montreal, Quebec, Canada, a company of Canada Filed June 12, 1967, Ser. No. 645,135 Claims priority, application Canada, Feb. 25, 1967,

U.S. Cl. 229-51 6 Claims Int. Cl. B65d 17/00, 45/00 ABSTRACT OF THE DISCLOSURE The present invention relates to cartons, particularly to reclosable end-loading cartons.

Many reclosable cartons have been proposed heretofor, however, a simple relockable feature has not been provided.

It is the main object of the present invention to provide a simple but effective locking means for reclosable cartons.

Broadly, the present invention comprises a locking section for a container comprising; a first and second panel, a tear-out section in said first panel and secured to said second panel, said tear-out section being separated from said first panel to form a hole in said first panel and remaining connected to said second panel when said box is initially opened, said tear-out section cooperating with said hole to hold said carton in closed position when said carton is reclosed.

Further features, objects and advantages of the present invention will be evident from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a plan view of a blank incorporating the present invention.

FIG. 2 is a partial perspective view showing a section through the middle of a blank folded to form a knocked down carton.

FIG. 3 is a perspective view of a closed, filled carton.

FIG. 4 is a perspective view of an opened carton and FIG. 5 is a section along the line 55 of FIG. 4.

The blank of FIG. 1 has afront wall 12, abottom wall 14, arear wall 16 and atop wall 18 interconnected byfold lines 20, 22 and 24 respectively. Connected to opposite ends of these walls viafold lines 26 and 28 are endwall forming flaps 30, 32, 34 and 36 respectively, some of which will be described in more detail hereinbelow. Afront cover panel 38 having a pair ofend tabs 40 connected thereto viafold lines 26 and 28 is joined at one side edge to the free edge oftop wall 18 byfold line 42. Acrease line 44 connects the opposite side edge ofpanel 38 to alocking flap 46. Thecrease line 44 is slit partially through the thickness of the blank to facilitate folding of theflap 46 into face-to-face relationship with thepanel 38.

Flap 46, in the illustrated embodiment, has a pair ofseparable sections 48 and 50 located in the corners of this flap and defined bythe free edges of the flap and lines ofweakness 52 and 54 respectively. The front wall 3,432,090 Patented Mar. 11, 1969 12 has a pair oftabs 56 and 58 defined by the free edge of theWall 12, pairs ofslits 60, 62 and 64, '66 andfold lines 68 and 70 respectively. Thesetabs 56 and 58 cooperate with thesections 48 and 50 of theflap 46 to form locking means as will be described hereinbelow. The present disclosure describes only the use of pairs of tabs and cooperating sections but obviously fewer or greater numbers of these may be used.

Each of theend flaps 32 in the illustrated embodiment has aband 71 defined by a pair ofspaced slits 72, 74 extending part way through the thickness of the board, theband 71 tears off between theslits 72 and 74 to remove a partial thickness of the board and permit opening of the container as will be more fully described hereinbelow. Alternate means of opening, wherein theslits 72, 74 and thus theband 71 are omitted, may also be used.

Atear line 76 extends across each of theflaps 36 to form atear strip 78 along the free end of these flaps. Thesetear strips 78 may be torn from theflaps 36 for opening of the container. Thetear line 76 has been shown as extending along an are but obviously these lines may be of any convenient shape.

To assemble the blank, adhesive is applied to the requisite sides of the blank in the shaded areas as indicated in FIG. 1. The first folding step is generally to fold theflap 46 into face-to-face relationship overlying thepanel 38 by folding alongcrease line 44. The adhesive strip onflap 46 secures theflap 46 andpanel 38 together. Next, the manufacturers joint. is secured by folding along the lines 20' and then 24 to bring theflap 46 into contact with the front wall .12. The adhesive on thetabs 56 and 58 secures these tabs to the tear-outsections 48 and 50 on theflap 46 to form the manufacturers joint (as shown in FIG. 2) and thereby provide a knocked down, easily erected carton particularly adapted for end loading. If desired, theflap 46 may be tacked at its edge adjacent the middle ofwall 12 by adhesive to form a stronger manufacturers joint, however, this tacking together of thewall 12 andflap 46 must be such that it is easily separated for opening of the container.

After the cartons have been erected and filled, the end flaps 30 and 34 together with the tabs: 40 are first folded to a position substantially perpendicular to the walls of the container with thetabs 40 overlying theflaps 30. If desired, thetabs 40 may be tacked to theflaps 30 by means of adhesive or the like so that theflaps 30 andtabs 40 are folded together, however, the joint between theseflaps 30 andtabs 40 must be relatively easily separated for opening of the container. Next, theflaps 32 are folded and secured in overlying relation to theflaps 30 and 34 by means of the banks or patterns of adhesive on theflaps 32 and finally, theflaps 36 are folded into overlying relationship to theflaps 30, 34 and 32 andtabs 40 to close the ends of the carton. Theseflaps 36 are secured to thetabs 40 by patches of adhesive in the appropriate location on theflaps 36 and to thebands 71 on theflaps 32 by strips or patterns of adhesive adjacent the free edges of theflaps 36 remote from thefold lines 26 and 28.

To open the carton theflaps 36 are torn off along thelines 76 to separate thetear strip 78 from theflaps 36 andbands 71 from theend panels 32. Alternatively, particularly if thebands 71 are not used and thestrips 78 are permanently secured to thepanels 32, the carton may be opened by running a finger or the like under thelines 76 to separatestrips 78 fromflaps 36 along thesaid lines 76. Thefront cover panel 38 andflaps 46 are also separated from thefront wall 12 wherebysections 48 and 50 are torn from theflap 46 and remain adhered to thetabs 56 and 58. Thetabs 56 and 58 together with thesections 48 and 50 are bent in towards the center of the box adjacent the free edge ofpanel 12, either manually or in any other suitable manner. Thesections 48 and 50 are larger in area than thetabs 56 and 58 bytriangular areas 100. Thetriangular areas 100 are formed because the free ends ofsections 48 and 50 are parallel to the end of the box while the adjacent ends oftabs 56 and 58 are defined byangled slits 60 and 66 (see FIG. 1). Thesetriangular areas 100 are not connected to thepanel 12 where the manufacturers joint is formed and therefore are movable outwardly as thetabs 56 and 58 are folded inward. The overlap of thesetriangular areas 100 with thefront wall 12 tends to prevent thetabs 56 and 58adjacent slits 60' and 66 from being folded inwardly, however, movement of the remainder of thetabs 56 and 58 is sufiicient to force theareas 100 outwardly, particularly adjacent the free edges of these areas (see FIGS. 4 and 5). Thetabs 56 and 58 combine with thesections 48 and 50 to form male elements of the locking combination for holding the top of the carton in closed position. Thesections 48 and 50 slide into the holes 80 (see FIG. 5), formed in theflaps 46 when these sections are torn therefrom in the initial opening of the carton, thereby to lock the carton in closed position. Thebentout areas 100 facilitate secure locking of the carton since they tend to positively engage the sides ofholes 80. To reopen the carton it is merely necessary to relatively displace thefront wall 12 along withtabs 56 and 58 andsections 48 and 50 so that theflap 46 will clear thesection 48 and 50 and be free to open.

Applicant has disclosed one form of the instant invention, however, other forms will be immediately apparent to those skilled in the art and therefore the claims are intended to include modifications falling within the terms thereof.

I claim:

1. In a reclosable folding carton having a locking flap and a wall cooperating to form an opening means for said carton, a separable section in said locking flap, said separable section being secured to a tab formed in said wall by an edge of said wall, a fold line spaced from said edge and a pair of slits extending between said edge and said fold line, said separable section separating from said locking flap and remaining connected to said wall thereby forming a hole in said locking flap and a projection on said wall when said carton is opened, said projection cooperating with said hole to hold said carton in closed position when said carton is reclosed.

2. A carton as defined in claim 1 wherein said separable section is larger than said tab and forms an overlap projecting across the boundary of said tab defined by one of said pair of slits.

3. In a reclosable carton having a front wall and a top wall, end forming flaps foldably connected to opposite ends of said top wall and a front cover panel connected to said top wall, and means connecting said end flaps and front cover panel, the improvement comprising; a locking flap underlying and secured in face-to-face relationship with said front cover panel, a separable section defined by lines of weakness in said locking flap, said separable section being spaced from the edge of said front cover panel remote from said top wall, means securing said separable section to a tab formed in said front wall by the top edge of said front wall, a fold line in said front wall and slits between said fold line and said top edge, said separable section separating from said locking flap and remaining secured to said tab thereby forming a hole in said locking flap and a projection on said front wall when said carton is opened, said projection cooperating with said hole to hold said carton in closed position when said carton is reclosed.

4. A carton as defined in claim 3 wherein said separable section is larger than said tab and forms an overlap projecting across the boundary of said tab defined by one of said pair of slits.

5. A carton as defined in claim 4 wherein said overlap is of triangular shape but is not secured to said front wall.

6. A carton as defined in claim 5 wherein there are two said sections and two said tabs on said locking flap and said front wall respectively and wherein each of said sections is defined on two sides by free edges of said locking flap.

References Cited UNITED STATES PATENTS 2,680,558 6/1954 Mai 229-51 2,970,743 2/1961 Joseph et al. 229--51 3,096,918 7/1963 Van Dyke et a1. 22951 XR 3,125,280 3/1964 Henry 22951 3,176,904 4/ 1965 Collura 229'-51 3,191,848 6/1965 Meyers 229-51 3,283,991 11/1966 Hughes 22951 3,295,742 1/1967 Coe 22951 XR 3,310,222 3/1967 Buttery 229-51 3,310,223 3/ 1967 Buttery 229-51 3,338,505 8/1967 Hughes 229-51 DAVIS T. MOORHEAD, Primary Examiner.

US. Cl. X.R.

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