Abstract:
A stand-up reclosable package is formed with a top and bottom seal, and a length-wise seal. The end of the bag is gusseted to form a flat, square shaped surface for the package to stand up. Another seal is formed length-wise along one side of the package to form the sides of the pack, defining the interior volume of the package. The top of the bag may be sealed in a manner consistent with existing vertical form fill and seal technology. The top of the package may have a reclosable feature. Additionally, the present invention provides a method of forming said reclosable stand-up package, including filling the package with desired contents as the package is formed and sealed.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/410,149, filed Sep. 12, 2002. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to manufacturing plastic containers. More particularly, the present invention relates to a reclosable bag or pouch capable of standing in an upright position on its own when filled with items, and to a method of making the bag.  
         BACKGROUND OF THE INVENTION  
         [0003]    Consumers desire stand-up, reclosable plastic bags and containers for their convenience for filling and storing dried foods, as well as liquid foods. There currently exist many so-called stand-up, freestanding or self-standing plastic bags. Known in the art are plastic bags incorporating a zipper-type closure device along the top opening or mouth of the bags. Further, there are self-standing plastic bags that incorporate a zipper-type closure device along its mouth.  
           [0004]    Some existing stand-up bags attempt to provide the stand-up capability merely by use of a simple bottom gusset alone, or, supplemented with seals added in the gusset structure. However, a simple bottom gusset sealed at its sides does not provide a normal consumer plastic bag with a stand-up feature with an adequate reclose feature. Such plastic bags are typically made from polyethylene film, which often is too limp to stand up from the gusseted bottom to permit easy reclosing of the bag. Consequently, it is difficult for the customer to get the bag to rest on a surface without toppling over or easily open and reclose, in both cases typically spilling the contents of the bag.  
           [0005]    Other consumer plastic bags have films of greater thickness, thus allowing them to stand up from a simple bottom gusset. Still other stand-up bags seal the bottom gusset into a base that is much more stable than the simple bottom gusset. Typically, these bottom gusset bags require gussets to be located on the top and bottom seals of the bag. Having a gusset on the top seal adds a great deal of complexity to the bag, especially when a reclosable feature is also incorporated into the bag. Specifically, multiple layers of film are folded within the seal, not permitting normal reclosable features to be used (e.g., zipper-type). Accordingly, the bag assembly and manufacturing process is more complex. Consequently, more time is needed to assemble the bags, leading to higher manufacturing costs.  
           [0006]    Furthermore, quite a bit of difficulty has been experienced in filling and emptying all of the above-disclosed bags. The bags do not stand up easily when empty, and a zipper-type closure is difficult to maintain in an open position when filling and emptying the bag.  
           [0007]    In order to provide a cost effective gusseted stand-up reclosable bag, it is contemplated that further improvements are needed before consumers will be provided with a plastic bag that completely meets their needs. These improvements must relate to a more stable stand-up base, one that will faithfully support the bag when empty as well as during and after filling, and a bag that allows for only the bottom of the package to be gusseted. Also, there is a desire for a simpler and less costly method of assembling a gusseted stand-up reclosable bag.  
         BRIEF SUMMARY OF THE INVENTION  
         [0008]    The present invention provides a stand-up gusseted bag with a reclosable feature and method of making same designed to satisfy the aforementioned needs. The purpose of the present invention is to provide simple inexpensive bags or stand-up pouches that are able to contain products such as snacks, confections, pet foods, liquids and the like.  
           [0009]    In one embodiment of the present invention, a package is formed with a top and bottom seal, and a length-wise seal. The bottom seal of the package is made by first folding the sides of the bag towards the center. While the sides are being held in place, the end of the bag is sealed (e.g., gusseted) to form a flat, square shaped surface for the package to stand up. Another seal is formed length-wise along one side of the package to form the sides of the pack, defining the interior volume of the package. The top of the bag is sealed in a manner consistent with existing vertical form fill and seal technology. Specifically, a flat, full-length seal across the width of the bag is made. Since there are no gussets in the top seal, the addition of a reclosable feature is possible.  
           [0010]    The reclosable feature of the present invention may be any conventional reclosing mechanism, such as a zipper, zipper-slider seal, easy-snap technology, or the like.  
           [0011]    Additionally, the present invention provides the method of forming said reclosable stand-up package, including filling the package with desired contents as the package is formed and sealed.  
           [0012]    Alternatively, a gusset may be formed on the top of the package.  
           [0013]    The package may be created in many styles. For example, one style involves placing an opening at the top of the package and then covering it with an additional piece of packaging film attached to the inside of the bag to maintain the package&#39;s integrity prior to initial opening. This opening may be a slit, a perforation, a punched opening, or the like. This opening may also be reinforced to eliminate the tendency of some packaging films to tear down the length of the bag.  
           [0014]    It is an object of the present invention to provide an efficient and cost effective apparatus and method for reclosing gusseted stand-up packages and retaining the contents therein.  
           [0015]    It is another object of the present invention to provide the package with the ability to maintain a stand-up capability as the contents of the package are consumed or removed.  
           [0016]    These and further aspects, objects and advantages of the present invention will become clearer in light of the following detailed description of the illustrative embodiments of this invention described in connection with the drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    Further objects and advantages of the present invention can be seen by reading the following detailed description in conjunction with the drawings in which:  
         [0018]    [0018]FIG. 1 is a perspective view of an embodiment of the present invention;  
         [0019]    [0019]FIG. 2 is a side view of the embodiment of FIG. 1;  
         [0020]    [0020]FIG. 3 is a rear view of the embodiment of FIG. 1.  
         [0021]    [0021]FIG. 4A is a perspective view of the embodiment of FIG. 1 with the package in the process of being opened.  
         [0022]    [0022]FIG. 4B is a perspective view of an alternative embodiment of the present invention with the package in the process of being opened.  
         [0023]    [0023]FIG. 5 is a perspective view of the present invention with the package in an opened orientation.  
         [0024]    [0024]FIG. 6 is a perspective view of the present invention with the package in a closed position.  
         [0025]    [0025]FIG. 7 is cross-sectional view of the reclosable mechanism of FIG. 6 in the closed position.  
         [0026]    [0026]FIG. 8 is a perspective view of the present invention with the package full of goods in a closed position.  
         [0027]    [0027]FIG. 9 is a perspective view of the present invention with the package full of goods in an opened position.  
         [0028]    [0028]FIG. 10 is a diagram of an embodiment of the formation of the present invention via vertical form fill and seal machinery.  
         [0029]    [0029]FIG. 11 is a diagram of an alternative embodiment of vertical form fill and seal machinery to form the present invention.  
         [0030]    [0030]FIG. 12 is a diagram of a further alternative embodiment of vertical form fill and seal machinery to form the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0031]    As mentioned above, the present invention relates to stand-up gusseted reclosable packages and the method of making the same. This invention may be applied to many different types of packaging machinery, and to other processing equipment and operations. For example, the present invention may be used to produce products or other containers for holding and containing materials. Additionally, the present invention may be used in self-standing items to display advertising, or formed using vertical form fill and seal (VFFS) machines as well as horizontal form fill and seal (HFFS) machines.  
         [0032]    Shown in FIGS.  1 - 9 , is a stand-up gusseted reclosable bag  10 . The present invention may be formed using machinery such as VFFS machinery, as shown in FIGS.  10 - 12  and discussed below.  
         [0033]    Referring to FIGS.  1 - 5 , a stand-up plastic bag  10  has a front wall  12 , a rear wall  14 , a pair of gusseted sides  16  and a flat bottom wall or portion  18 , defining an interior volume  20 . An open bag mouth  22  is defined at the upper edges of the walls ( 12 , 14 , 16 ).  
         [0034]    In one embodiment, the front wall  12  and rear wall  14  has opposite longitudinal edges joined together by a seal at contiguous portions of material on the exterior surface thereof, which complete formation of a seal as a continuous self-standing structure that defines, with bottom wall  18 , a stand-up base of the bag.  
         [0035]    The gusseted sides  16  have portions  24  interconnected to form a substantially flat bottom wall extending between the front  12  and rear  14  walls, and sides  16 . Sides  16  may also have lower portions joined by seals to lower portions of the front  12  and rear  14  walls at contiguous portions of material to form a support band  17  that connects to and extends below the bottom wall  18 . For example, as shown in FIG. 3, the bag  10  may have a base seal that utilizes gussets  16  on the sides of bag  10  in forming the flat bottom portion or base  18 .  
         [0036]    The walls are composed of a multi-layered film. The film is preferably a plastic, for example, polyethylene, and may be heat-sealable and/or coextruded. However, it is contemplated that any paper, thermoplastic, or like material may be utilized. For example, materials may be used to permit use of the package in a microwave, freezer and refrigerator.  
         [0037]    Referring to FIGS.  1 - 3 ,  4 A and  4 B,  5  and  9 , the mouth opening  22  at the top of bag  10  may be of numerous styles such as a slit, a perforation or a punched opening. The reclosable feature of the present invention applied to close the mouth opening may be any conventional re-closing mechanism. For example, a zipper, slider, seal, Zip-Loc™, or the like, or easy-snap technology may be utilized.  
         [0038]    As shown in FIGS.  1 - 9 , easy-snap technology  26  is a reclosable feature for packages. The Easy Snap device  26  utilizes a fold over snap feature as shown in FIGS. 6 and 7. The easy-snap technology is disclosed in U.S. Pat. Nos. 6,350,057, 5,983,594, 5,944,425, 5,937,615, 5,928,749 and 4,679,693, all to Forman, and is incorporated herein by reference.  
         [0039]    As shown in FIGS.  1 - 4 B, mouth opening  22  may also be reinforced to eliminate the tendency of some packaging films to tear down the length of the bag. Mouth opening  22  may also be covered on the exterior of the package to protect or close off the opening with various removable materials such as a strip of tape  28 , a label or the like. An adhesive  30  may be utilized to supplement the resealable easy-snap device  26 . Alternatively, a seal may be used at the top of the bag to completely cover the bag opening  22 , as well as the resealable feature.  
         [0040]    In its most common environment, the method of assembly of the present invention is a component of a larger manufacturing operation and results in a gusseted reclosable stand-up bag  10 . For example, the self-standing flat-bottomed bag with a reclosable feature may be automatically formed on a VFFS machine, as shown in FIGS.  10 - 12 .  
         [0041]    One embodiment of formation of the present invention, a vertical form fill and seal machine is shown in FIG. 10. In this embodiment, a longitudinal seal is first formed through normal VFFS machine operation creating a tube of film that travels down a round forming collar. The VFFS machine advances bag film exactly one bag length and stops.  
         [0042]    Referring to FIG. 10, in operation, a sealing bar and feature press  34  close simultaneously on a web of multi-layered film  36 , and a top transverse seal  38  of the bag  10  is formed. The reclose feature (i.e., Easy Snap, Zipper, Slider) is may be applied at this time. While the top seal and reclose feature are being formed, a serrated cut-off knife  40  is actuated through the film  36  separating the newly formed bag  10  from the end of a tube of film  36 . The cut-off knife is then retracted. Subsequently, the sealing bar and feature press  34  open simultaneously. The feature press  34  may continue to grasp film  36  to increase dwell time for proper reclose feature formation. The end of the film tube  36  relaxes to its natural round shape.  
         [0043]    A secondary sealing bar and gusseting fingers  42  close on film  36  simultaneously creating a bottom transverse seal  44  and the flat stand-up geometry  46  of bag  10 . Two separate gusseting fingers  48  are located on opposite sides of bag  10 . A specially designed rectangular forming tube attachment on the inside of the film tube  36  aids in the formation of the flat bottom geometry  46 . The width and depth of the gusseted portion of the bag are determined by the size of this attachment, which is determined by the machine user.  
         [0044]    Product may begin to be dumped into bag  10  as soon as the secondary seal bar and gusseting fingers  42  close. The forming tube attachment, gusseting finger and secondary sealing bars  42  are preferably mechanically aligned to the bottom edge of film  36  to ensure that the bottom seal  44  is formed exactly along the edge of film  36 . This ensures that no excess film has to be trimmed from the bag to provide a neat seal appearance. Additionally, no extra film must be discarded during the formation of the bottom seal.  
         [0045]    In FIG. 11, an alternative embodiment of VFFS machinery is shown. This embodiment is a variation of the embodiment of FIG. 10 in which the film tube  36  is advanced a second time during the formation of bag  10 . This allows the bottom edge of film  36  to be realigned to the sealing bar  42  prior to the formation of the bottom transverse seal  44  and stand-up geometry  46 . The advantage of this action is that there is no need for a secondary seal bar and mechanism  42  to actuate it.  
         [0046]    In FIG. 12, a further alternative embodiment of VFFS machinery is shown. This embodiment is another alternative to the embodiment of FIG. 10 in which the film is reversed (see arrow A) during the formation of bag  10 . This allows the bottom edge of film  36  to be aligned to the secondary seal bar  42  prior to the formation of the bottom transverse seal  44  and stand-up geometry  46 . The advantage of this action is that the bottom film edge may be aligned electronically through a VFFS machine computer controller. This eliminates the mechanical alignment of the secondary sealing bars, gusseting fingers, and forming tube attachment.  
         [0047]    It should be noted that other variations of the sequence of operation of the embodiments of FIGS.  10 - 12  are contemplated, based on the many different designs and functions of VFFS machines in the market today. For example, some VFFS machinery operates with continuous motion versus intermittent motion. It is contemplated that this technology could be adapted to work with the present invention as well.  
         [0048]    Additionally, the present invention may be adapted to be applied to horizontal form fill and seal flow wrapping technology. This should be differentiated from the horizontal form, vertical fill and seal market in which “stand-up pouch” style bags are formed.  
         [0049]    The seals of the present invention may be accomplished via a seal bar or similar device or procedure. As stated above, the seals are preferably located longitudinally along a portion of the bag, for example, along the rear wall  14  of the bag  10 , shown as  32  in FIGS. 2 and 3. The seal  32  preferably extends below the flat bottom  18  portion of bag  10 . See FIGS.  1 - 3 .  
         [0050]    The present invention has several advantages over existing packages in use today. Typical flat-bottom bags are required to be gusseted on the top and bottom seals. Having a gusset on the top seal adds a great deal of complexity to the addition of a reclosable feature. Multiple layers of film are folded within the seal not allowing normal reclosable features to be used, such as a zipper or slider mechanism. The present invention provides a reclosable feature on a gusseted stand-up bag. Moreover, the present invention requires the utilization of the special sealing jaws and gusseting manufacturing equipment for only the bottom of the package. Consequently, manufacturing time, assembly complexity and costs are greatly reduced.  
         [0051]    Those skilled in the art will further appreciate that the present invention may be embodied in other specific forms without departing from the spirit or central attributes thereof. In that the foregoing description of the present invention discloses only exemplary embodiments thereof, it is to be understood that other variations are contemplated as being within the scope of the present invention. Accordingly, the present invention is not limited in the particular embodiments that have been described in detail therein. Rather, reference should be made to the appended claims as indicative of the scope and content of the present invention.