Abstract:
This invention provides a support for a carton which supports said carton during printing comprising a flat portion which is inserted into said carton. This invention further provides a method of printing on a carton comprising the steps of supporting said carton with a support comprising a flat portion; and printing on said carton.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates to a support to hold a carton while printing on the carton. More particularly, this invention relates to a support that is inserted into a carton to hold the carton while printing on the carton.  
         BACKGROUND OF THE INVENTION  
         [0002]    Carton blanks for contact lens containers are shipped from the carton supplier with most of the necessary information printed on them, with blank areas on the cartons for receipt of variable information, such as, the lot number, barcodes, design (e.g., power), and expiration date of the product. Carton blanks are often supplied having pre-glued areas, e.g. the lid or side flaps. The pre-glued areas of the carton have two layers of paper, and therefore, these areas of the carton are not flat. Further, fold lines in the carton, which form the edges at the intersection of two surfaces cause the surfaces of the carton to be irregular. Attempts to print on the flat blanks can result in illegible printed information.  
           [0003]    One solution is not to print on the carton and to add additional information by adding an adhesive label to the carton; however, adhesive labels are expensive. Another alternative is to emboss areas of the carton which do not overlap when the carton is flat; however, that limits the areas which can be printed on, and cannot readily be used to print some kinds of information, e.g. barcodes.  
           [0004]    There is a need for an apparatus to remedy the problem of printing on a partially pre-glued carton so that legible print can be added to the carton.  
         SUMMARY OF THE INVENTION  
         [0005]    This invention provides a support for a partially pre-glued carton, said support comprising:  
           [0006]    a flat portion which can be inserted into the partially pre-glued carton and which is used to support at least one surface of said carton during printing.  
           [0007]    In the preferred embodiment said flat portion further comprises holes in said flat portion, wherein a vacuum source is attached to said holes in said flat portion.  
           [0008]    This invention further provides a method of printing on a partially pre-glued carton comprising the steps of:  
           [0009]    inserting a support into a partially pre-glued carton; and printing on said carton.  
           [0010]    The support provides a flat portion which holds the surface of the carton flat so that legible print can be added to one or more surfaces of the carton. This invention can be used to add information, particularly variable information to cartons, particularly contact lens cartons by the contact lens manufacturer in a cost-effective way. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    [0011]FIG. 1 is a perspective view of the support of this invention.  
         [0012]    [0012]FIG. 2 is a side view of a support partially inserted into a carton.  
         [0013]    [0013]FIG. 3 is a cross-sectional view of a support fully inserted into a carton.  
         [0014]    [0014]FIG. 4 is a perspective view of the carton fully inserted into a carton having cutaway areas showing the support. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]    One of the preferred supports is shown in the drawings. FIG. 1 shows a support  10  of this invention. The support has a flat portion  15  having holes  11  which are connected to a vacuum source (not shown) by vacuum connectors  31  (shown in FIG. 3). The flat portion  15  is the area of the support  10  to which one or more than one surface of the carton is held against by a vacuum during printing. In an alternative embodiment, the support  10  can consist of more than one flat portion which can support and make it possible to print on more than one surface of the carton which are not in-line, i.e., surfaces which are at right angles or parallel to eachother. In another preferred embodiment, the support can comprise a flat portion without the holes and vacuum.  
         [0016]    The surface of the carton held against the flat portion is the surface of the carton which receives the variable printed information. Preferably, more than one surface of the carton is held against the flat portion and at least one surface, more preferably more than one surface, of the carton receives the variable printed information. The holes  11  are preferably not located in the areas of the carton to receive the variable printed information. The holes  11  are shown as circular in shape; however, any shape can be used, including square, rectangular, etc. Further, the holes are shown as many small openings; however, one or a few larger holes could be used on the support. Ordinary experimentation with the carton and printing area can be used to determine the hole arrangement that works best for a particular printing area and carton.  
         [0017]    The flat portion  15  can comprise metal or rubber. In the preferred embodiment, the flat portion  15  comprises rubber adhered to metal. The flat portion  15  is preferably attached to sides  14  which will provide structure to hold the flat portion  15  stiff during printing on the carton. The sides  14  are connected to a bottom  21  (shown in FIGS. 2 and 3). The flat portion  15 , the sides  14  and the bottom  21  are all connected to a tapered nose  12  that preferably is tapered on all four sides. The sides  14 , bottom  21 , and tapered nose  12  can be made out of any material, preferably rubber or metal, more preferably metal. In the preferred embodiment the support  10 , except the flat portion, is machined out of a single piece of metal, e.g. aluminum, and the flat portion consists of a metal sheet with rubber bonded to it. Aluminum sheets with bonded rubber is commercially available, e.g. from Edmund Scientific Co. The aluminum sheet with bonded rubber is bolted to the rest of the support by bolts (not shown). If the rubber becomes worn or otherwise damaged, it can be replaced without having to replace the entire support. If the flat portion has holes in it, the holes can be added by machining them into the flat portion.  
         [0018]    The tapered nose  12  makes it easier to insert the support  10  into a carton. In the preferred embodiment, the support  10  is sized to be about the same width w (in FIG. 1) as the inside width of the carton to assist in alignment of the carton with a printer. Alternatively, a spring plate (not shown) can be added to the support and used inside the carton to properly align the carton on the support. In the preferred embodiment, the length of the flat portion  15  of the support  10  is about the same length as the carton, but it can be any length as long as the area of the carton to receive print is supported. In the preferred embodiment, the height h (in FIG. 1) of the support  10  is about two-thirds the height of the carton, but any height can be used as long as the support can be inserted into the carton. In fact, the support  10  can take any form as long as the support  10  has a flat portion  15  against which the carton is supported during printing. For example, if the flat portion  15  has sufficient strength, the support  10  may only consist of the flat portion  15 , or a flat portion and the tapered nose.  
         [0019]    [0019]FIGS. 2, 3, and  4  show various views of the support  10  inserted into a carton  29 . FIG. 2 shows that the tapered nose  12  of the support  10  is inserted into the carton  29  first. The carton  29  is a partially pre-glued carton, which preferably presents itself to the support  10  partially erected with foldable end flaps  28  in line with the top panel  26  and bottom panel  27  of the carton  29 . The foldable side flaps  24  of the carton  29  are in-line with the side panels  25  of the carton  29 . In an alternative embodiment, one or both ends (consisting of end flaps and side flaps) of the carton  29  may be pre-glued as long as there is at least one opening in the carton  29  for the support  10  to be inserted into the carton  29 .  
         [0020]    [0020]FIGS. 3 and 4 show the support  10  fully inserted into the carton  29 . The support  10  is inserted into the carton  29  until at least one side flap  24  hits at least one alignment guide  16 , which is part of the support  10 . Alternatively, alignment can be achieved by an alignment guide which can be located to contact other portions of the carton including end flaps or top or bottom panels, or alignment can be achieved using an alignment system, such as a vision system and/or a robot. After the support  10  has been inserted into the carton  29 , the vacuum source (not shown), if present, is activated and the portions of the carton to be printed on are held against the support  10  and the carton  29  is moved into position for the printer  32 . Alternatively, the printer  32  can be moved to the carton  29 . FIG. 3 shows a printer head  33  contacting the surface of the top panel  26  of the carton  29 .  
         [0021]    [0021]FIG. 4 shows the support  10  fully inserted into a carton  29  after information  43  including bar codes and numbers have been printed on the carton  29 . One of the end flaps  28  and the top panel  26  of the carton  29  were printed on. The support makes is possible to print on more than one sides, panels, or flaps of the carton, individually referred to as a surface, collectively referred to as surfaces of the carton. The holes  11  and flat portion  15  of the support  10  can be seen in the cutaway areas of the carton.  
         [0022]    In the preferred method of using the support, the carton is partially erected by a pick-station which picks up a flat blank, partially erects it and places it onto an index wheel. The index wheel moves the carton toward the support  10 . The support  10  inserts itself into the carton, moves itself and the carton up to a printer, turns on a vacuum source, if present, and holds the carton in position while the printer prints on the carton. After the variable information is printed on the carton, the support moves the carton away from the printer, to the index wheel, and places the carton onto the index wheel. The index wheel has a guide on it that catches the carton while the support is removed from the carton.  
         [0023]    The printer can be any type of printer for printing on a carton, for example, a laser, embosser, or thermal printer, preferably laser or thermal printer. The support is most suited for contact printing operations, such as thermal printing. The preferred thermal printer is a Thermocode 5775 Thermal Transfer Coder by Open Date using a resin ink, preferably, a ribbon SP330 resin by Open Date. Other printers including the Smart Date 2 thermal printer can be used to print on the cartons.  
         [0024]    The preferred embodiments have been described herein; however, alternative embodiments would be known to a person of ordinary skill in the art, which would fall within the scope of the invention defined by the claims.