Abstract:
This invention relates to a secondary locking system for wrap-around carriers. A secondary male lock is held in the vertical position by a female flap leaning against the male lock. The adjacent pairs of secondary male locks and corresponding female locks are aligned with each other along a single longitudinal line which traverses an adjacent article contained within the carrier.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    This invention relates generally to mechanical locks for holding overlapping flaps of a wrap-around carton in place. More particularly, it is a secondary locking system without a primary lock system.  
           [0003]    2. Prior Art  
           [0004]    When fabricating a carton from a paperboard blank, opposite ends of the blank are conventionally attached to each other by glue or by a mechanical lock to form the bottom panel of the carton. In the case of a wrap-around carton, flaps located on the ends of the blank typically are overlapped and engaged with one another by mechanical locks formed in the flaps to form the bottom panel of the carton. Since the bottom panel must maintain its integrity throughout the use of the carton, it is essential that the locking system be capable of supporting the weight of the packaged articles, and remain engaged during shipping and handling of the constructed carton.  
           [0005]    One approach to provide a stable mechanical lock assembly utilizes both primary and secondary locks. An example of such locking system is disclosed in U.S. Pat. No. 5,443,203 to Sutherland.  
         SUMMARY OF THE INVENTION  
         [0006]    Briefly described, in a preferred form, it is the object of the present invention to provide a secondary lock system that is more secure and does not become accidentally unlocked resulting in the carrier becoming opened discharging the containers contained therein.  
           [0007]    The object of this invention is achieved by providing a secondary lock system. The secondary lock system has a male lock that is inserted into the female opening and held in the vertical position in the carrier by a flap in the female lock system. An arcuate tab on this flap aids in holding the secondary male lock in the vertical position.  
           [0008]    Preferably, each secondary male lock is aligned longitudinally to the corresponding female secondary opening to be directly in front of a container contained in the carton. All of the secondary male locks and female openings are longitudinally aligned.  
           [0009]    These and other objects, features, and advantages of the present invention will become more apparent upon reading the following specification in conjunction with the accompanying drawing figures.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    [0010]FIG. 1 is a plan view of a blank which incorporates the locking features of the present invention.  
         [0011]    [0011]FIG. 2 is a perspective view of the bottom of the carton with the secondary locks about to be engaged with the female openings.  
         [0012]    [0012]FIG. 3 is a perspective view of the bottom of the carton with the locks held in proper position.  
         [0013]    [0013]FIG. 4 is a perspective view of the carton formed from the blank of FIG. 1 and loaded with containers. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0014]    The present invention is intended primarily for use with wrap-around carriers containing bottles of the type used to contain soft drinks, beer and other types of drinks. It is especially useful for containers that are made of paperboard or plastic and are not as rigid as glass.  
         [0015]    The blank for forming the carrier of this invention is illustrated in FIG. 1. This blank  10  is designed to contain six beverage containers arranged in two rows of three each. The blank  10  is formed from a foldable sheet of material, such as paperboard. The blank has a secondary locking panel  12 , which is foldably connected to bottom panel  14  by fold line  16 , and in turn connected to lower side panel  18  by fold line  20 . Lower side panel  18  is connected to middle side panel  22  by fold line  24 , which in turn is connected to upper side panel  26  by fold line  28 , and in turn connected to top panel  30  by fold line  32 . In a similar fashion, top panel  30  is connected to upper side panel  34  by fold line  36 , which in turn is connected to middle panel  38  by fold line  40  and in turn connected to lower side panel  42  by fold line  44 . Lower side panel  44  is connected to bottom panel  46  by fold line  48 .  
         [0016]    This carton  10  has apertures  50  for containing the heels of containers contained therein. The tops of the containers are restrained from falling out of the ends by the top end panels. Top end panel  52  is connected to top panel  30  by fold line  54 . Top end panel  52  is connected to triangular gusset panel  56  by fold line  58  which in turn is connected to triangular web panel  60  by fold line  62 . Triangular web panel  60  is connected to tuck-in panel  64  by fold line  66 , which in turn is connected to upper side panel  26  by fold line  68 . Tuck-in panel  64  has a holding flap  70  for holding top end panel  52  in proper position in contact with the end containers in the carton.  
         [0017]    In a similar fashion, top end panel  72  is connected to top panel  30  by fold line  74 . Tuck-in panel  72  is connected to triangular gusset panel  76  by fold line  78  and in turn connected to triangular web panel  80  by fold line  82  and finally connected to tuck-in panel  84  by fold line  86 . Tuck-in panel  84  is connected by fold line  88  to upper side panel  26 . Tuck-in panel  84  has a holding flap  90 .  
         [0018]    Top end panel  52  is connected to triangular gusset panel  92  by fold line  94  and in turn connected to triangular web panel  96  by fold line  98 . Triangular web panel  96  is connected to tuck-in panel  100  by fold line  102 . Tuck-in panel is connected to upper side panel  34  by fold line  104  and has a holding flap  106 . End panel  72  is connected to triangular gusset panel  108  by fold line  110  and in turn connected to triangular web panel  112  by fold line  114 . Triangular web panel  112  is connected to tuck-in panel  116  by fold line  118 , which in turn is connected to upper side panel  34  by fold line  120 . Tuck-in panel  116  has a holding flap  122 .  
         [0019]    As previously mentioned, this carton is unique in that it has only a secondary locking system. Secondary male locks  124 A-D are connected to secondary locking panel by fold line  126 . The secondary female locking system is located in bottom inner panel  46  and has secondary female flaps  128 A-D formed by cut lines  130 A-D. The secondary female flap has a fold line  132 A-D for folding the flap into a locked position. The arcuate tabs  134 A-D are used for holding the male locks in the locked position.  
         [0020]    It will be understood by those in the art that the preferable carrier is symmetrical about a horizontal line of bisection, as viewed from FIG. 1. This symmetry aids in the efficient production of the present carrier. The carrier need not have such symmetry, although it is preferred. As shown, the blank  10  is rectangular in shape and includes straight edges, which also makes for an efficient layout of the blank in a web from which the blanks are cut.  
         [0021]    Finger apertures or other types of apertures or straps for carrying the carrier may be provided in the top panel  30 .  
         [0022]    Unlike conventional locking systems, the carton of this invention does not include both a primary locking system and a secondary locking system. Rather, it has been found that a secondary locking system will satisfactorily hold the carton together. This is especially true if certain conditions are met. The first condition is that each set of secondary male locks and secondary female openings be aligned longitudinally along the center of the container being carried in front of which they are located. The second condition is that each of these containers has a degree of flexibility which allows the container to be somewhat compressed in the locking arrangement which secures the lock in the locked position.  
         [0023]    It will be noticed from the drawings that each pair of secondary locking locks are aligned longitudinally, i.e. the length of the blank (A-A′). The secondary male locks  124 A-D are aligned longitudinally with cut line  130 A-D of the secondary female locks. The longitudinal line that runs through the carrier and through the containers also runs through the corresponding secondary male lock and corresponding secondary female opening.  
         [0024]    This invention provides a locking system that is more secure than prior art locking systems. The secondary locks are secured in that the secondary male locks  124 A-D are held in the vertical position in respect to the carrier by secondary female flaps  128 A-D and arcuate tabs  134 A-D illustrated in FIG. 1. If the secondary male locks  124 A-D were allowed to be parallel to the secondary locking panel  12 , they could easily become disengaged.  
         [0025]    The carton of this invention is formed from the blank of FIG. 1 by moving the top panel  30  of the blank over the containers. The blank  10  is pulled tight about the containers and the secondary locking panel  12  is overlapped on bottom panel  46  with the secondary locking panel  12  being on the outside. Slits  136  facilitate locking the locks one at a time. The secondary male locks  124 A-D are bent along fold line  126  and are punched in where the enter into primary female openings by cut lines  130 A-D. Secondary female flaps  128 A-D project inwardly with arcuate tabs  134 A-D holding the secondary male locks  124 A-D in the vertical position. The secondary male locks  124 A-D are held in the vertical position by secondary female flaps  128 A-D. The arcuate  130 A-D on each secondary female flap lean against the secondary male lock  124 A-D and assist in holding the secondary male locks in the vertical position. Holding the secondary male locks  124 A-D in the vertical position ensures that the locks are not accidentally withdrawn. It will be noticed from FIG. 1 that the secondary locks are aligned along longitudinal lines parallel to line A-A′ in FIG. 1. Top end panels  52  and  72  are pushed inwardly into the end containers by pushing tuck-in panels  64 ,  84 ,  100  and  116  and the respective triangular shaped web panels  60 ,  80 ,  96 , and  112  and the triangular gusset panel  56 ,  76 ,  92  and  108 . Holding flaps  70 ,  90 ,  106  and  122  hold the top end panels  52  and  72  in proper position with the holding flaps being between the container and the sides of the carton.  
         [0026]    While the invention has been disclosed in its preferred forms, it will be apparent to those skilled in the art that many modifications, additions, and deletions can be made therein without departing from the spirit and scope of the invention and its equivalents as set forth in the following claims.  
       UNIQUE FEATURES OF THIS INVENTION  
       [0027]    The use of a secondary locking system which is aligned longitudinally with the containers being carried is a unique feature of this invention. This is facilitated by the use of containers or articles with flexible side walls. This invention features top end panels that are held in position by a gusset consisting of a triangular web panel, triangular gusset panel, and tuck-in panel and holding flap. This is also believed to be a unique feature.  
         [0028]    This invention is particularly useful on containers that have some flexibility such as plastic tubs, PET bottles and composite containers and the like, but it should be understood that the invention is not so limited as it can also be used on glass bottles.  
         [0029]    This carrier is designed to be erected on a static feedlock system where there are no moving parts with compression fingers pulling the carrier together by the heel apertures. The carrier is pulled together somewhat beyond what is required for locking and then the locking becomes secure as the compression is relaxed allowing the flexible articles being carried to secure the locks.  
         [0030]    Because of the longitudinal arrangement of the locks in relation to the containers, the stress is placed in a longitudinal direction rather that in a diagonal direction which facilitates holding the locks in the locked position. Because of the resiliency of the containers, compression on the heel apertures can overcompensate in locking the locking mechanism which is then slightly loosened after the lock has been set. This can be arranged between the locks so that they can be locked one at a time without putting undue stress on the adjoining lock.