Abstract:
The combination of a pair of paperboard carton members positioned in a paperboard tray member, wherein the carton members have projections extending from the bottom wall thereof through related openings in adjacent walls of the tray member, and wherein at least one of the members includes means for temporarily holding the carton closure flaps in a generally vertical open position against the carton end wall panels while the cartons are being filled on a packaging line.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to containers such as paperboard cartons, and more particularly to arrangements for temporarily holding carton upper closure flaps in a vertical open position, so the cartons can be filled while they are being carried in trays on a conveyor of a packaging line. 
     2. Description of the Background Art 
     A background art search directed to the subject matter of this invention conducted in the United States Patent and Trademark Office disclosed the following United States Letters Patent: 
     
         ______________________________________1,063,845 1,132,292   1,482,857   2,216,2992,588,455 2,690,285   2,965,279   2,990,9953,330,466 3,365,109   3,369,652   3,572,5773,940,053 4,134,533   4,356,952   4,372,476UK 783,932     UK 2,118,147A                 GER 2,034,825                             GER 2,106,357FR 1,409,752     IT 541,920  EP 0 588 751 A1______________________________________ 
    
     None of the patents uncovered in the search discloses the combination of a pair of paperboard carton members positioned in a paperboard tray member, wherein the carton members have projections extending from the bottom wall thereof through related openings in adjacent walls of the tray member, and wherein at least one of the members includes means for temporarily holding the carton closure flaps in a generally vertical open position against the carton end wall panels while the cartons are being filled on a packaging line. 
     SUMMARY OF THE INVENTION 
     It is a primary object of the invention to provide an improved arrangement for holding the upper closure flaps of cartons in a vertical open position to facilitate filling of the cartons as they are being carried along in trays on a conveyor of a packaging line. 
     Another object of the invention is the provision of an arrangement for holding carton closure flaps in an open position, as the cartons are being carried in trays along a conveyor of a packaging line, which arrangement utilizes the engagement between the ends of the carton flaps and projections extending upwardly from side wall panels of the trays. 
     Yet another object of the invention is to provide an arrangement for holding carton closure flaps in an open position, as the cartons are being carried in trays along a conveyor of a packaging line, which arrangement utilizes a novel carton structure wherein the carton end walls and the carton closure flaps are so formed and folded that the flaps can be maintained in an open position without engagement with side wall panels of the trays. 
     These and other objects of the invention will be apparent from an examination of the following description and drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an isometric view of a pair of cartons positioned within a tray embodying features of the present invention; 
     FIGS. 2A and 2B are vertical sectional views taken on lines 2A and 2B of FIG. 1, respectively. 
     FIG. 3 is a plan view of a blank of foldable sheet material from which the tray illustrated in the other views may be formed. 
     FIGS. 4 and 5 are isometric views showing the manner in which the tray illustrated in FIG. 1 is formed from the blank illustrated in FIG. 3. 
     FIGS. 6-10 are views similar to those of FIGS. 1-5, but illustrate a modified form of the invention. 
     FIGS. 11-15 are views similar to those of FIGS. 6-10, but illustrate another modified form of the invention. 
     FIG. 16 is an isometric view of one carton and a portion of another carton in a tray embodying another form of the invention. 
     FIG. 17 is a plan view of a blank of foldable sheet material from which the carton illustrated in FIG. 16 may be formed. 
     FIG. 18 is an enlarged view of a portion of the structure illustrated in FIG. 17; 
     FIG. 19A is a vertical sectional view taken on line 19A--19A of FIG. 16; 
     FIGS. 19B, 19C, and 19D are views similar to that of FIG. 19A but illustrate several steps in the carton forming operation. 
    
    
     It will be understood that, for purposes of clarity, certain elements may have been omitted from certain views where they are believed to be illustrated to better advantage in other views. 
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings for a better understanding of the invention, it will be seen that a pair of cartons C are shown positioned in a tray T which may be formed from the blank TB of paperboard illustrated in FIG. 3. 
     Each of the cartons C includes an opposed pair of side wall panels 8 and an opposed pair of end wall panels 10 foldably joined to and extending between the respective side wall panels. 
     The bottom of each carton is closed by bottom closure flaps 12, which are foldably joined to lower edges of the carton side and end wall panels in the same manner as are the bottom closure flaps of the embodiment of the carton illustrated in FIG. 17. 
     The upper end of the carton may be closed by a pair of upper closure flaps 16 foldably joined on fold lines 17 to upper ends of end wall panels 10, and the primary feature of the invention is to provide means for holding the carton upper closure flaps 16 in an open position, as shown in FIG. 2, so the flaps will not be in the way during the filling operation. 
     As best seen in FIGS. 3-5, Tray T includes a bottom wall panel 20 having opposed pairs of side wall panels 22 and end wall panels 26 foldably joined to opposed side and end edges thereof along fold lines 23 and 27, respectively, and upstanding therefrom. Side wall panels 22 have extending therethrough openings in the form of slots 23a located adjacent fold lines 23 which join the side wall panels to the bottom wall panel. 
     As best seen in FIGS. 1 and 2B, the function of the tray side wall panel openings 23a is to receive portions of tabs 14 which project outwardly from the carton bottom wall flaps that are joined to the carton end wall panels. This engagement helps maintain the cartons in the proper location within the tray. 
     Side wall panels 22 are also provided near their ends with diagonal fold lines 23b which form triangular sections 24. 
     The tray end wall panels 26 are connected to the side wall panels 22 by means of corner flaps 28 which are foldably joined to opposite ends of each end wall panel 26 along a fold line 29. Corner flaps 28 may be adhesively secured to adjacent side wall panel triangular sections 24. 
     As best seen in FIGS. 1, 2, and 5, because corner flaps 28 are wider than side wall panels 22, they project upwardly beyond the upper edges of the side wall panels and serve to engage the lower end portions of the carton upper closure flaps 16 and thereby retain them in a vertical open position against the related end wall panels 10 of the cartons. Thus, the closure flaps may be kept out of the way when the cartons are being filled. 
     Turning now to FIGS. 6-10 it will be seen that a slightly modified form of the invention is shown. The cartons C shown in these Figures have the same structure as the cartons illustrated in FIG. 1, but the tray T1 is different from the tray T shown in the earlier described views. In all of the views elements of a structure corresponding to those of another structure have been identified by similar or related numerals. 
     In Tray T1 the side wall panels 122 have centrally located projections 124 extending upwardly therefrom for engagement with portions of the upper closure flaps of both of the two cartons in the tray to hold the closure flaps in an open position. 
     Turning now to FIGS. 11-15 it will be seen that a slightly modified form of the invention is shown. The cartons C shown in these Figures have the same structure as the cartons illustrated in FIG. 1, but the tray T1 is different from the tray T shown in the earlier described views. In all of the views elements of a structure corresponding to those of another structure have been identified by similar or related numerals. 
     In Tray T2 the side wall panels 222 each have a pair of laterally spaced projections 224 extending upwardly therefrom for engagement with portions of the upper closure flaps of both of the two cartons in the tray to hold the closure flaps in an open position. 
     Now turning to FIGS. 16-19C, it will be seen that yet another embodiment of the invention is illustrated. 
     In this embodiment, although a pair of cartons C1 are carried in a tray T3, the tray side and end wall panels 322 and 326 are of equal height with no projections extending upwardly therefrom for contact with the carton closure flaps. Instead this embodiment of the invention depends on the construction of the cartons to maintain the closure flaps in an open position without the need to rely on contact between the carton closure flaps and projections on the tray side wall panels. 
     Carton C1, illustrated in FIG. 16, may be formed from the blank C1B illustrated in FIG. 17. The carton body includes opposed pairs of side and end wall panels 108 and 110 foldably joined to each other along parallel fold lines 111, as well as a glue flap 106 foldably joined to an end wall panel on a fold line 107. 
     Bottom closure flaps 112 are foldably joined to the lower edges of the side and end wall panels along fold lines 113. As previously mentioned, the bottom closure flaps joined to the end wall panels 110 each have a projection 114 extending therefrom for engagement with related openings in the tray side wall panels 322. 
     Closure of the upper end of the carton is accomplished by a pair of upper closure flaps 116 foldably joined to the upper portions of the carton end wall panels 110, as hereinafter described. 
     As best seen in FIGS. 15, 17, and 19A-19D, each carton end wall panel 110 includes a major portion 110a and a minor portion 110b foldably joined to minor portion 110a on a fold line 117b. 
     Also each upper closure flap 116 includes a major portion 116a and a minor portion 116b foldably joined to major portion 116a on a fold line 117c. 
     Referring now to FIGS. 19A-19D, it will be seen that the minor portion 110b of each end wall panel 110 is adhesively secured to minor portion 116b of the related upper closure flap 116, and is foldably joined thereto along a fold line 117. 
     In a conventional carton closure flap folding arrangement the fold between the upper edge of the carton side or end wall and the closure flap normally creates a spring-like action that tends to prevent the closure flap from lying against the carton side or end wall. 
     However, in the present invention, the spring-like action is eliminated, by the relationship between that closure flaps 116 and the end walls 110, so the closure flaps are free to remain in a vertical open position as seen in FIG. 16. Thus no additional hold down means, such as contact with the tray side wall projections, are required. 
     After the cartons have passed along the conveyor filling line and have been filled, the upper closure flaps may be folded over to the position illustrated best in FIG. 19D with the minor portions of the closure flap and the carton end wall lying against the inner surface of the carton end wall major portion, and with the major portion of the closure flap extending inwardly therefrom in a horizontal plane. 
     Again referring to FIGS. 17, 18, and 19D, it will be seen that the carton end walls 110 may each be provided with a handle structure indicated generally at 130 which includes a handle flap 132 which is defined by a fold line 133 joining the flap to the carton end wall and by a cut line 135. 
     In order to facilitate access to the handle flap 132, end wall 110 includes a pair of triangular entry tabs 136 located adjacent and immediately below the handle flap and which are defined by a pair of diagonally extending fold lines 137 and a vertical cut line 139 therebetween. 
     In order to lift the carton by the handles, the entry tabs are depressed, as shown in FIG. 19D, so the handle flap can be grasped and pushed into the carton and folded against the inner surface of the closure flap minor portion. Thus, a strong four-ply handle is created. 
     Thus it should be understood that the invention provides different ways to maintain carton closure flaps in a vertical open position, so the cartons can be filled as the cartons are carried in trays on a conveyor of a packaging line.