Abstract:
A bulge reducer is configured for use on a form, fill and seal packaging machine for gable top packages. The machine has a drive element and plurality of discrete package carriers for conveying the packages along a conveyance path through the machine. The bulge reducer includes a drive member operably connected to the machine station chain. A reciprocating member is operably connected to the drive member for the reciprocation toward and away from the conveyance path. The reciprocating member contacts one of the package side walls as the package moves along the conveyance path to exert an inward force on and urge the side wall inwardly of the package.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention is directed to an apparatus and method for reducing the bulge in a paperboard based carton. More specifically, the invention pertains to an in-line bulge reducer, in a form, fill and seal packaging machine, that contours the middle portions of carton side wall. 
         [0002]    Gable top cartons are in widespread use. Such cartons have been known for most of the twentieth century. The characteristic simplicity and widespread acceptance have helped to maintain their popularity as cartons for traditional products, such as liquid food products, for example, milk and juice. 
         [0003]    Improvements to gable top cartons continue including improvements in the carton materials. Such improvements are often directed to increasing the effectiveness of the materials to reduce oxygen ingress and flavor loss. As a result of the increased effectiveness of the materials, the overall thickness of the materials can be reduced. This saves material “weight” which provides an overall cost savings. 
         [0004]    In addition, in that products are often packaged in process that provide for longer shelf lives and increased product lives, many such cartons are produced in larger sizes. As a result, the cartons tend to appear larger. This may be the result of package bulging, which may not be aesthetically pleasing and may not be acceptable to certain product packagers. 
         [0005]    Moreover, many of the process plants use certain downstream equipment, that is equipment downstream of the form, fill and seal machines, that may not accommodate these somewhat larger cartons. As a result, the cartons may require manual handling for these downstream processes and operations. 
         [0006]    Accordingly, there is a need for a carton bulge reducer. Desirably, such a bulge reducer can be fitted into existing form, fill and seal machines. More desirably such a bulge reducer operates without additional drives, such as motors. Most desirably, such a bulge reducer applies a force to the carton that increases as along the carton side, toward the center of the carton. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    A bulge reducer is configured for use on a form, fill and seal packaging machine for gable top packages. The package has upstanding side walls and a sealed gable top. The machine has a drive element, such as a station chain, and plurality of discrete package carriers for conveying the packages along a conveyance path through the machine. 
         [0008]    The bulge reducer includes a drive member operably connected to the machine station chain. A present drive member is a sprocket having petal-like element that engage the station chain. 
         [0009]    A reciprocating member is to the drive member for the reciprocation toward and away from the conveyance path. The reciprocating member, preferably a roller, contact one of the package side walls as the packages move along the conveyance path. Contacting the package side wall exert an inward force on and urges the side wall inwardly of the package. 
         [0010]    To effect reciprocation of the roller, a cam element is mounted on the sprocket to contact a cam follower on the roller. In this manner, cam element moves the cam element into contact with the follower to reciprocate the roller. 
         [0011]    In a present system, the roller is biased away from the conveyance path, as by a spring. A pressure platen is disposed opposite the roller, relative to the conveyance path. 
         [0012]    A form, fill and seal packaging machine includes a drive element, such as a station chain, a conveyor operably connected to the chain for moving the cartons through stations of the machine and a carton bulge reducer disposed at a top sealing station. The bulge reducer includes a drive member, such as a sprocket, operably connected to the machine drive element and a reciprocating member, such as a roller, operably connected to the sprocket. A cam on the sprocket urges a cam follower on the roller into the conveyance path. The roller is biased away from the path. 
         [0013]    The roller reciprocates toward and away from the conveyance path to contact one of the package side walls as the packages move along the path to exert an inward force on and urge the side wall inwardly of the package when the package is at the top sealing station. 
         [0014]    A pressure platen is disposed opposite the reciprocating element relative to the conveyance path. The roller is moved into the conveyance path to reach an inner most extension toward the path substantially corresponding to a central location of a respective carton carrying member. 
         [0015]    These and other features and advantages of the present invention will be apparent from the following detailed description, in conjunction with the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0016]    The benefits and advantages of the present invention will become more readily apparent to those of ordinary skill in the relevant art after reviewing the following detailed description and accompanying drawings, wherein: 
           [0017]      FIG. 1  is a perspective view of a form, fill and seal packaging machine for gable top packages, the machine having a bulge reducer embodying the principles of the present invention; 
           [0018]      FIG. 2  is a gable top package; 
           [0019]      FIG. 3  is top perspective view of the bulge reducer showing cartons in carton carrier in the station chain; 
           [0020]      FIG. 4  is a lower plan view of the bulge reducer, showing the mounting to the machine; 
           [0021]      FIG. 5  is a top, inside perspective view of the bulge reducer showing the roller in contact with the carton shown in phantom lines; 
           [0022]      FIG. 6  is a view opposite that of  FIG. 5  showing the pressure platen against which the carton bulge reducer is actuated; 
           [0023]      FIG. 7  is a top view of the station chain and the bulge reducer; and 
           [0024]      FIG. 8  is a view similar to  FIG. 3 , showing the sprocket engaged with the station chain. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]    While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated. 
         [0026]    It should be further understood that the title of this section of this specification, namely, “Detailed Description Of The Invention”, relates to a requirement of the United States Patent Office, and does not imply, nor should be inferred to limit the subject matter disclosed herein. 
         [0027]    Referring now to the figures and in particular to  FIG. 1 , there is shown a form, fill and seal packaging machine  10  having a package bulge reducer  12  embodying the principles of the present invention. The form, fill and seal machine  10  is configured generally to store a series of carton blanks in a flat, folded form, erect the blanks into a tubular form, fold and seal the bottom flaps of the carton, fill and seal the cartons as they move through the machine  10 . The form, fill and seal packaging machine  10  can be such as that disclosed in Katsumata, U.S. Pat. No. 6,012,267, which patent is assigned to the assignee of the present invention and is incorporated herein by reference. 
         [0028]    To effect the form, fill and seal process, the packaging machine  10  includes a carton magazine  14  for storing the flat, folded carton blanks, a carton erection station  16  and a bottom forming and sealing station  18  to erect the cartons C into a tubular form and to fold and seal the carton bottom B. The machine  10  typically also includes a sterilization station  20  for sterilizing the cartons C and includes a filling station  22  at which the cartons C are filled with product. Following the filling station  22 , the carton top panels are folded and sealed at a fin F to form the well recognized gable top G, at a top folding and sealing station  24 . 
         [0029]    The cartons C are then off loaded from the form, fill and seal packaging machine  10 . The packaging machine  10  illustrated includes a conveyor  26  for transporting a series of cartons C to and through each of the stations. In a typical machine  10 , the conveyor  26  is a chain-type conveyor that includes a series of carriers or sleeves  28  in which the cartons C are carried. The chain  26  is driven by a drive  30  that also operates or drives other components within the machine  10 . 
         [0030]    During the form, fill and seal operation, a carton C, having the bottom wall B folded and sealed, and optionally having a closure mounted to the carton and sterilized, is moved in the carrier  28  by the station chain  26  to the filling area  22 . At the filling area  22 , the carton C is filled with a predetermined volume of product. The filled carton C (with the top still open) is then moved on to the top sealing station  24 . 
         [0031]    Various types of top sealers are known. One type of top sealer uses a horizontally reciprocating jaw or anvil arrangement. The anvils are mounted to the packaging machine by a pair of pivoting arms such that the movement of the anvils is actually a slight arcuate movement with the anvils contacting the carton in a downward movement portion of the cycle. Such an arrangement is illustrated in Cicha, U.S. Pat. No. 6,430,899, which is commonly assigned with the present application and is incorporated herein by reference. Another type of top sealer includes pivoting arms that move inward to contact and urge the top flaps to close the carton. 
         [0032]    In both of these types of top sealers, as the gable G flaps are moved toward one another and the fin F panels are sealed, the gases above the product (in the carton C) and within the walls of the carton C are trapped within the carton C. And, as the carton C is sealed, the volume inside the carton C is slightly reduced. This creates a tendency for the carton C to flex outwardly at the largest surfaces and in particular at the surfaces that are not thickened (such as at seams). This, in effect, results in the large side walls W of the carton C bulging slightly. 
         [0033]    The present bulge  12  reducer applies an inward force on a wall W 1  of the carton C as the carton C is moved into and is at top sealer  24 . The bulge reducer  12  is driven by the station (conveyor drive) chain  26  so that no additional drives, such as motors or the like, are required. 
         [0034]    The bulge reducer  12  includes a linearly driven, reciprocating element  32  that is configured to move into contact with the carton C as the carton C moves into the top sealer  24  and such that the maximum travel of the reciprocating element  32  is reached as the top fin F panels are sealed to one another. The reciprocating element  32  includes a roller  34  that is mounted to a reciprocating arm  36  to move into and out of the carton conveyance path P as the carton C is conveyed through the top sealer  24 . 
         [0035]    The roller  34  is mounted to a U-shaped bracket  38  that supports a shaft  40  positioned in the center of the roller  34 , about which the roller  34  rotates. The bracket  38  is mounted to the arm  36  to reciprocate the roller  34  and bracket  38 . The arm  36  is mounted for reciprocation in a carriage  42  mounted to the machine  10 . The arm  36 , bracket  38  and roller  34  (the roller assembly  44 ) move as a unit relative to the carriage  42 . The roller assembly  44  is mounted to the carriage  42  by a biasing element, such as the illustrated coil spring  46 , to bias the roller assembly  44  outwardly, away from the carton path P. 
         [0036]    A pressure platen  48  is positioned opposite the roller  34 , across the carton path P. The platen  48  provides a stationary surface against which the carton C is held as the roller  34  moves into contact with the carton wall W. In this manner, as the roller  34  applies pressure to the wall W, the carton C is “squeezed” between the roller  34  and the platen  48 . 
         [0037]    The roller assembly  44  has a movement profile so that the roller  34  contacts the carton side wall W 1  after the leading corner L has passed the plane N 34  defined by the axis A 34  of the roller  34  and moves inward to apply a force on the side wall W 1 , as the carton side wall center W c  moves toward the axis plane N 34 . In this manner, the maximum inward travel of the roller  34  is at about the center of the carton W c  (and the center of the carton carrier  38 ). As the center of the carton W c  moves beyond the roller axis plane N 34 , the roller  34  begins to move outward away from the carton C so that the roller  34  no longer contacts the carton C as the trailing edge or corner T of the carton passes the roller N 34  axis plane. 
         [0038]    The present bulge reducer  12  uses the station chain  26  to drive the roller assembly  44  in its reciprocating motion. This has a number of advantages, first of which is that additional or separate drives (such as motors) are not needed to drive the reducer  12 . Rather, it is the conveyance movement of the cartons C through the machine  10  that drives the bulge reducer  12 . In addition, in that the movement of the bulge reducer  12  directly corresponds to the movement of the cartons C, synchronization of the carton C movement and roller assembly  44  movement is inherent by virtue of the drive arrangement. 
         [0039]    In a present bulge reducer  12 , a drive wheel  50  is a sprocket having petal-like elements  52  that extend radially outwardly from the wheel  50  to engage the station chain  26 . A cam element  54  is mounted to the drive wheel  50 . The cam element  54  has a lobe or cam surface  56 . The cam element  54  is configured to engage a cam roller or follower  58  that is mounted to the assembly  44 . In a present assembly  44 , the follower  58  is mounted to the bracket  38 , below and aligned with the roller axis A 34 . In this manner as the drive wheel  50  is driven (by the station chain  26 ), the cam element  54  rotates. In turn, as the cam lobe  56  approaches and contacts the cam follower  58 , the lobe  56  exerts a force on the follower  58  which in turn moves reducer roller  34  into contact the with the carton side wall W 1 . Continued movement of the station chain  26  continues the rotation of the drive wheel  50  and in turn the cam element  54 . As the lobe  56  passes the cam follower  58 , the biasing element (spring)  46  force returns the roller assembly  44  to the retracted or withdrawn position. 
         [0040]    The bulge reducer  12  is timed so that the maximum extension of the roller  34  occurs just as the top sealer  24  is sealing the top fin F panels. It will be appreciated that as the bulge reducer urges  12  the carton side wall W 1  inward, the level or height of the liquid in the carton C will rise. This is due to the reduced volume of the carton C with the wall W 1  urged inward. When the volume is reduced (and consequently the liquid height is increased) and the top fin F panels are sealed, a lower pressure region is created above the liquid in the sealed carton C when the liquid returns to its level in an at rest carton C. By lower pressure, it can simply be a lesser pressure than would otherwise occur when the fin F panels are sealed with the entrapped gases above the liquid. As a result, the walls of the carton tend to be drawn inward by the lower pressure, rather than bulge outward by a slightly pressurized region above the liquid. 
         [0041]    In the present disclosure, the words “a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular. 
         [0042]    All patents referred to herein, are hereby incorporated herein by reference, whether or not specifically done so within the text of this disclosure. 
         [0043]    From the foregoing it will be observed that numerous modifications and variations can be effectuated without departing from the true spirit and scope of the novel concepts of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated is intended or should be inferred. The disclosure is intended to cover by the appended claims all such modifications as fall within the scope of the claims.