Abstract:
A support system for holding a sheet of material being cut by a laser has a base and a number of needles extending upwardly from the base. A vacuum generator or suction mechanism is in communication with a lumen in each needle to hold the sheet atop the bed of needles and spaced from the base so as to avoid scorching the sheet by the laser.

Description:
[0001]    This claims the benefit of U.S. Provisional Patent Application Ser. No. 62/174,578, filed Jun. 12, 2015 and hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention generally relates to the cutting and creasing industry, and more particularly to a system for and method of cutting paperboard and other materials for packages. 
         [0003]    Packaging is an important aspect of marketing. The package in which goods are packed and presented, in a store for example, may determine if the goods will be appealing to a potential buyer in the store or not. Thus the packaging appearance can have a direct effect on the sales of merchandise. 
         [0004]    A known preliminary requirement to construct a package is preparing or purchasing a pre-treated paperboard and/or plastic and/or paper based material. Paper based material may be of different types. Exemplary types may be: waxed paper, cartridge paper, art paper, etc. Henceforth, throughout the description, drawings and claims of this disclosure, the terms paperboard, paperboard, card-stock, display board, corrugated fiberboard, paperboards of different paper based material, folding boxboard, carton, blanks, blister cards, plastics, boards/papers with enhancement (UV coating, printing, for example) and lamination, and so on, may be used interchangeably. This disclosure may use the term paperboard as a representative term for the above group as well as variations thereof. 
         [0005]    The pre-treatment of paperboard may include the following acts: creating folding lines along the paperboard to ease and provide accurate folding of the paperboard; piercing the paperboard in different areas; creating embossment in different areas of the paperboard; cutting the raw paperboard into predefined profiles; and so on. 
         [0006]    Some common techniques for preparing a pre-treated paperboard include the acts of placing the paperboard between dies. Exemplary types of dies include a cutting-die; a creasing-die; an embossing-die; a scoring-die; a combination of the different types of dies; and so on. Other known techniques for preparing pre-treated paperboard may include the use of laser. One known technique for cutting board is described in U.S. Published Patent Application No. 2013/0126489, which is incorporated by reference entirely herein. 
         [0007]    When laser beam is used for cutting paperboards, burn marks may be formed on the paperboard itself. This may damage the esthetics of the paperboard and resulting package. Further the laser beam may damage the system itself in the long run. 
         [0008]    One paperboard-handling system disclosed in the &#39;489 patent application includes an under-laser raiser. Such an under-laser raiser may prevent burn marks (from smoke, and/or reflections of the laser&#39;s beam, for example) on the paperboard. Furthermore the under-laser raiser may protect the substrate and/or area underneath the paperboard from the heat of the laser beam. 
         [0009]    The under-laser raiser of the &#39;489 patent application has a plurality of protruding elements, substantially parallel one to the other. The plurality of protruding elements protrudes from a base. The protruding elements have a needle-like shape. A paperboard is placed in a substantially horizontal position on the top of the protruding elements. 
         [0010]    A coupling and stabling mechanism is used to couple and stabilize the paperboard to the top of the protruding elements. The coupling and stabling mechanism includes a plurality of gaps (openings) in the base and a suction mechanism. The gaps are holes. The suction mechanism is a vacuum generator. The suction mechanism is intended to couple and stabilize the paperboard to the top of the protruding elements. 
         [0011]    The vacuum is intended to hold the paperboard, blanks, and/or other cut parts (of the paperboard, for example) in required position on the under-laser raiser. This may be advantageously when the paperboard has been pretreated and parts of it are cut/and/or creased and thus may be free from other holding means. The vacuum may also evacuate the smoke caused by treatment of the paperboard by the laser beam, and advantageously prevent burn marks on the paperboard. 
         [0012]    The system of the &#39;489 application relies upon the retention of the paperboard on the tips of the protruding elements via the vacuum or suction generated by the suction mechanism communicated to the paperboard through the holes or gap in the base from which the elements protrude. The effectiveness of such a retention mechanism is due in large part to the ability of the suction mechanism to act upon the paperboard spaced from the holes in the base by the protruding elements. Such an arrangement requires a closed system surrounding the base, protruding element and paperboard arrangement and/or a powerful suction mechanism. Such requirements tend to be a restriction on the efficient, consistent and reliable processing of the paperboard through the system, among other drawbacks. 
         [0013]    An improved system and method for laser cutting paperboard to address these and other identified drawbacks with the invention of the &#39;489 application and other prior systems are needed and provided by this invention as disclosed herein below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
           [0015]      FIG. 1  is a schematic view of an exemplary system for processing paperboard into carton blanks in which this invention may be utilized; 
           [0016]      FIG. 2  is a perspective view of one embodiment of a needle bed and base on which a paperboard sheet is positioned for laser cutting in the system of  FIG. 1  according to this invention; and 
           [0017]      FIG. 3  is a cross-sectional view taken along line  3 - 3  of  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    Turning now to the drawings in which like numerals and/or labels represent like elements throughout the several views, exemplary embodiments of this invention are described. For convenience, only some elements of the same group may be labeled with numerals. The purpose of the drawings is to describe exemplary embodiments and is not for production purpose. Therefore features shown in the drawings are for illustration purposes only and are not necessarily drawn to-scale and were chosen only for convenience and clarity of presentation. 
         [0019]      FIG. 1  is a schematic diagram illustrating various exemplary elements of an exemplary embodiment of a paperboard-processing system  10 . Examples of existing systems for processing paperboard into package blanks are available from Bobst North America, Inc. www.bobst.com. The illustrated exemplary embodiment of the paperboard-processing system  10  is shown to include a feeder station  12 , a die-rule and counter-die station  14 , a laser cutting station  16 , a stacker  18 , a controller (not shown) and a conveyor  20 . 
         [0020]    In operation, initially the feeder station  12  gets a paperboard item  22  and feeds it toward the conveyor  20 . The conveyor  20  may convey the paperboard item  22  toward and/or through the die-rule and counter-die station  14 . The die-rule and counter-die station  14  operates to pre-treat the paperboard  22  and can include one or more of a variety of operations, including, but not limited to, adding creases, cuttings, embossing of areas, piercing, apertures, indentations, scoring, printing, etc. 
         [0021]    Next the conveyor  20  may convey the pre-treated paperboard item  22  toward the laser station  16  to be further treated, for example, by a laser  16 a cutting the paperboard item. The conveyor  20  may then convey the paperboard  22  toward the stacker  18 . The stacker  18  may stack the paperboard items  22  into a pile or stack. The controller may synchronize and control one or more of the modules or stations of the paperboard-handling system  10 . 
         [0022]    The controller may get input signals or data from different sensors along the paperboard-handling system  10 , and accordingly, respond by sending commands to one or more modules. These commands may include, but are not limited to: setting the velocity of the conveyor, starting/stopping operation, grabbing/releasing paperboard, setting motion direction of the paperboard to forward or backward, as well as other commands and/or combination of two or more of any of these commands. In some embodiments, the controller may get information from an operator. Other examples of paperboard-handling system  10  may comprise other modules, more of the same modules, only some of the described modules, etc. and as such, the configurations illustrated in  FIG. 1  are non-limiting examples. 
         [0023]      FIG. 2  depicts one embodiment of a support assembly  24  for laser cutting of a work piece generally and a sheet of paperboard according to various embodiments of this invention. The support assembly  24  may support and stabilize the paperboard  22  in a fixed position while a laser&#39;s beam is working on or treating the paperboard  22 . The support assembly  24  may include a number of upright, spaced elements, tubular members or needles  26 , substantially parallel one to the other. The needles  26  may protrude from a base  28 . Each needle has a tapered upper tip  30 , an elongated slender body  32  and bottom end  34  apposite from the tip  30 . A longitudinal lumen  36  is found in each needle  26  and is in communication with a port proximate the tip  30  of the needle  26 . The paperboard  22  may be placed in a horizontal position on the tips  30  of the needles  26 . The base  28  may have a housing  38  enclosing a void  40  which is in communication with the lumen  36  of each needle  26 . The needles  26  may be spaced from each other and all be of substantially the same height. 
         [0024]    The support assembly  24  may include a vacuum generator or suction mechanism  42  in communication with the void  40  of the base  28 . Suction mechanism  42  such as, but not limited to a vacuum generator may couple and stabilize the paperboard  22  to the top of the needles  26  as shown in  FIG. 3 . 
         [0025]    The suction or vacuum generated in the void  40  of the base  28  is communicated from the base  28 , through the lumens  36  of the needles  26  and ports and ultimately to the tops  30  of the needles to retain the paperboard  22  on top of the needles  26 . The stable and stationary positioning of the paperboard on the needles  26  allows for the accurate and precise cutting of the paperboard  22  by the laser. Moreover, since the paperboard  22  is supported above the base  28  by the needles  26  during cutting, the laser does not scorch or mar the paperboard  22 . 
         [0026]    Additionally, once the cutting o other treatment of the paperboard  22  by the laser is completed, the vacuum generator may be reversed to produce a slight puff or flow of air through the lumens  36  to elevate the paperboard  22  for advancement from the support system  24  and toward the next station or module of the system  10 . The laser may be used to cut entirely through the paperboard  22 , cut partially through the paperboard  22 , create a series of cuts or perforations in the paperboard  22  or any other treatment of the paperboard  22 . 
         [0027]    In exemplary embodiments the height of the needles  26  may be designed such that the focal point of the laser beam will not strike the base  28  of the support system  24 , advantageously protecting the base  28  from the maximum heat of the laser beam. The top of the needles  26  may be designed to have a small surface such that if and/or when the laser beam hits the needle  26  it will hit only a small area. The length (height) of the needles  26  may also be designed such that if and/or when a laser beam strikes it the heat will cool along the length of the needle before reaching the base  28 . Further, in some exemplary embodiments the material of the needles  26  and/or base  28  may be resistance to heat. The shape of the needles  26  may be diamond-like cross shape, narrower at the top end and at the base end in relation to the middle part of it, for example, and so on. 
         [0028]    In some exemplary embodiments the material of the needle  26  and/or base  28  may be such that light will not reflect from it. In other exemplary embodiments part or the entire needle  26  and/or base  28  may be coated with anti-reflect coating. 
         [0029]    Laser beam resistant material particles that will not reflect the laser light directly back to the paperboard but more in cross direction. This may defocus a laser beam that hits them, for example. The air flow may enable the vacuum from the vacuum generator  42  to remove the smoke away from the paperboard, and so on. Some of the embodiments may be a combination of two or more of the above, etc. 
         [0030]    From the above disclosure of the general principles of this invention and the preceding detailed description of at least one embodiment, those skilled in the art will readily comprehend the various modifications to which this invention is susceptible. Therefore, I desire to be limited only by the scope of the following claims and equivalents thereof.