Abstract:
An improved pouch has a crimped or squeezed mouth region to facilitate pouch opening and hold open during filling. Mouth edge curls are disclosed for enhancing mouth opening. Roller nip and crimp roller apparatus is disclosed. Pouch conditioning methods are disclosed.

Description:
RELATED APPLICATION 
       [0001]    Applicant claims the benefit of the filing date of Sep. 4, 2008 of its U.S. provisional patent application Ser. No. 61/190,949, which application is expressly incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to pouch forming, filling and sealing, and more particularly to preparing and handling pouches and the mouths thereof to enhance subsequent opening for filling, whether in bandolier or individual pouch applications. 
       BACKGROUND OF THE INVENTION 
       [0003]    Pouches are formed from a variety of relatively thin materials, typically by folding an elongated web, then transversely sealing together the folded plies at intervals (corresponding to pouch pitch) to form sealed side seams with open mouths therebetween at the pouch tops. As so prepared, an indefinite length or “bandolier” of serially attached pouches is formed. Such a bandolier can be directed as a train of pouches through opening, filling, sealing and cutting apparatus or stations, or individual pouches can be cut, one from the other, gripped at the side seams and transported as individual pouches through opening, filling and sealing operations. One such apparatus for so handling individual pouches is applicant&#39;s co-pending U.S. patent application Ser. No. 11/688,205, filed Jan. 29, 2007, published on Aug. 9, 2007 under No. US 2007/0180794, both application and publication incorporated herein by reference as if fully set out herein. 
         [0004]    Because of web stiffness characteristics, including the relative flimsy or thin nature of typical pouch material, the pouches do not open robustly when air is directed at the “mouth” of the pouch. The web will sometimes fold over on itself and not open due to the air not being able to find a path into the mouth. Another problematical situation is presented when the pouch opens but re-closes immediately after being opened due to web “memory” which is not effectively resisted by a material stiffness too low to overcome such memory. 
         [0005]    Prior methods of pouch opening are varied. One such method biases the web material at the mouth of the pouch. A forming guide “curls” the web on one or both sides of the pouch mouth such that the internal pouch material surfaces flair away from each other. The result is a lead-in or path into the pouch for the pressurized air that will do the opening. The guide work required for this method is difficult to setup and can result in a wrinkle being introduced into the web. 
         [0006]    Another method involves making one side of the pouch, termed a “lip”, higher than the other. This configuration allows the pressurized air to have a surface that helps separate and direct the air into the pouch. 
         [0007]    Neither of these methods addresses the issue of material stiffness and memory which may result in the pouch re-closing. 
         [0008]    Accordingly, it is desired to enhance the opening of pouches, presented either in a train or bandolier or as cut and individually presented continuously or intermittently to pouch opening stations. 
         [0009]    It is further desired to provide improved pouch handling apparatus for producing pouches whose mouths are more reliably and consistently opened for filling. 
         [0010]    It is further desired to provide improved pouch structure for enhancing reliable and consistent mouth opening for filling. 
       SUMMARY OF THE INVENTION 
       [0011]    A preferred embodiment according to the invention contemplates crimping the pouch plies in a mouth region, thus increasing the stiffness of the pouch at its mouth, which tends to robustly open and remain open when an opening airstream is applied thereto. 
         [0012]    One embodiment of the invention includes a nip defined by a pair of operably opposed rollers with each roller having raised surfaces that run parallel to each other and are located about the circumference of preferably each roller. The doubled pouch web is passed between the rollers and is “crimped” between them under some pressure, which may be supplied by biasing one or both rollers into the nip such as applied by a spring. The rollers can be driven or non-driven. The action of passing the web, in particular the region of pouch mouth, through the nip between the rollers imparts a crimp pattern comprising a series of ridges and valleys into the web at the mouth area or region and preferably just below the upper edges of the mouth. These ridges and valleys cause each ply of the affected web at the pouch mouth to have a greater stiffness much like a corrugated material. This increased stiffness resists the otherwise tendency of the pouch plies to fold over and obstruct the opening action of the air when pouches are presented to an opening station. This stiffness allows the pouch tops to “pop” open robustly when opening air is blown into the pouch, and effectively resists any ply memory which may tend to urge the mouth to prematurely close. In addition, the web will naturally curl outwardly on both sides of the pouch mouth above the crimp and provide a pathway for the pressurized opening air. Once opened, the now higher material stiffness overcomes the tendency of the pouch to re-close. 
         [0013]    This method and apparatus is easy to setup, do not impart un-wanted wrinkles into the web, and the apparatus can be disengaged by simply pulling or moving the rollers away from the web. The method can also be used with or without an extended “lip” or ply extension from one of the pouch plies above or within the crimp. 
         [0014]    Other variations of this method and apparatus are possible. The use of one roller with a back-up surface defining a nip is possible as well as using two or more rollers in tandem or individually sequencing one after each other. For example, one roller could be oriented on one side of a pouch with another crimping roller or rollers downstream on another side of the pouch. Additionally, the rollers can be smooth with no crimp pattern to achieve only the “curl” at the mouth and to limit the amount of induced stiffness. 
         [0015]    These and other objects and advantages will be readily appreciated from the following detailed written description and from the drawings in which: 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is an elevational view of pouches in a pouch bandolier running through a crimping nip according to the invention; 
           [0017]      FIG. 1A  is a diagrammatic plan view along lines  1 A- 1 A of  FIG. 1  of a nip according to the invention, and defined by two rollers having a crimping pattern; 
           [0018]      FIG. 1B  is a diagrammatic plan view of a nip according to the invention defined by two rollers, one having a crimping pattern in a peripheral surface and one a smooth peripheral surface; 
           [0019]      FIG. 1C  is a diagrammatic plan view of a nip according to the invention having two rollers, each with a smooth peripheral surface; 
           [0020]      FIG. 2  is a perspective view of the invention as shown in  FIGS. 1 and 1A ; 
           [0021]      FIG. 3  is a perspective view of an individual pouch formed as in  FIGS. 1 ,  1 A and  2 ; 
           [0022]      FIG. 4  is a diagrammatic cross-sectional view taken along lines A-A of  FIG. 2  but modified to show one crimp pattern surface and one smooth surface of opposed rollers as in  FIG. 1B ; 
           [0023]      FIG. 5  is a diagrammatic cross-sectional view also taken along lines A-A of  FIG. 2  but modified to illustrate a nip formed by two smooth surface opposed rollers as in  FIG. 1C ; and 
           [0024]      FIG. 6  is a perspective view similar to  FIG. 3  but illustrating a pouch having mouth edges curled way one from the other and a crimp in each pouch ply spaced from said mouth edges. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]    Turning now to the drawings, it will be appreciated that pouches described herein can be made from a variety of suitable pouch materials, including but not limited to synthetic materials, metal or metallized materials, aluminized materials and any other suitable materials as desired. It will also be appreciated that similar components of the embodiments in the drawings are designated with identical numbers. 
         [0026]      FIGS. 1 and 2  illustrate one embodiment of the invention in which a bandolier  10  of serially connected pouches  12 ,  14 ,  16 , for example, are transported through a nip  20  defined by two rollers  22 ,  24 . The bandolier comprises at least two adjacent pouch plies  26 ,  28  (see  FIGS. 1A ,  1 B,  1 C) folded about a fold line  30  along which is the pouch bottom. Each pouch has a mouth region  32  defined by the adjacent plies  26 ,  28 . Each mouth region  32  terminates in an edge  34 ,  36  as indicated in the FIGS. 
         [0027]    Each pouch is defined by a sealed side seam  38 ,  39  formed transversely across plies  26 ,  28 . Eventually, and either before or after pouch opening or filling, the pouches  12 ,  14  and  16  are separated about respective cut lines  40 ,  41 , for example, to form individual pouches such as those shown in  FIGS. 3 and 6 . 
         [0028]    Preferably while in bandolier form  10 , the pouches are transported through nip  20  in the machine direction MD, with plies  26 ,  28  at the mouth region  32  squeezed by an appropriate pressure presented by the nip such as between rollers  22 ,  24 . 
         [0029]    Rollers  22 ,  24  are rotatably mounted via a frame member  44  and any suitable roller drive or support structure  46  as may be desired. One, both or neither of the rollers  22 ,  24  can be driven. Each counter-rotate with respect to the other as plies  26 ,  28  are transported therebetween, and as illustrated by the direction arrows R- 1 , R- 2  of  FIG. 2 . Rollers  22 ,  24  are preferably biased with respect to each other to form nip  20 . One or both rollers  22 ,  24  can be biased toward the other. 
         [0030]      FIGS. 1 ,  1 A and  2  illustrate one preferred embodiment of the invention for conditioning a pouch  50  as shown in  FIG. 3 . In  FIGS. 1 and 2 , two opposed rollers  22 ,  24  each have a peripheral surface  46  defining a crimp pattern  47  of a plurality of parallel ridges  48  and valleys  49  as illustrated. 
         [0031]    When plies  26 ,  28  are transported through nip  20 , a corresponding crimp pattern is applied in the respective plies. It will be appreciated that the ridges  48  and valleys  49  of the rollers  22 ,  24  may be offset one from the other or may be directly opposed, all to form a crimp pattern in mouth region  32  and preferably up to the mouth edges  34 ,  36 . 
         [0032]    A resulting pouch  50  ( FIG. 3 ) whether individually cut, then opened, or a plurality of pouches  50  still in bandolier form for opening and filling (not shown) is thus formed. 
         [0033]    The resulting crimped mouth region  32  in this pouch  50  is of such a stiffness that it robustly opens and remains open when an airstream  52  is directed onto the mouth. Edges  34 ,  36  do not tend to reclose after opening due at least in part to this increased stiffness. 
         [0034]    An alternative pouch  54  ( FIG. 6 ) is likewise formed by drawing plies  26 ,  28  through a nip  20 , but in a slightly elevated path with respect to rollers  22 ,  24 . In this embodiment, the crimp pattern of the rollers is disposed beneath, or spaced slightly from the mouth edges  34 ,  36 . The crimp in the plies is still in mouth region  32 , but is so below the edges  34 ,  36  that the result is a curling of the respective edges  34 ,  36  outwardly and away from each other as in  FIG. 6 . This forms an even wider mouth  56  facilitating opening of the individual or bandolier formed pouch mouths. 
         [0035]    Further embodiments of the invention are illustrated in  FIGS. 1B ,  1 C,  4  and  5 . 
         [0036]      FIG. 1B  and  FIG. 4  illustrate one embodiment where a nip  20  is formed by rollers  60 ,  62 . One roller  60  has a smooth peripheral surface  61  while roller  62  is like that of crimp pattern roller  24  in  FIG. 1A . This embodiment results in an application of a crimp pattern  48 ,  49  of roller  62  to ply  28 , while ply  26  remains substantially smooth. Since the crimp is applied up to edges  34 ,  36 , the pouch mouth remains relatively straight ( FIG. 4 ). 
         [0037]    This configuration produces a pouch like that of  FIG. 3 , with the exception of one ply remaining smooth. Nevertheless, the crimping of one ply so stiffens the mouth of such a pouch that opening and remaining open is enhanced. And further, if the plies are elevated through nip  20  of  FIG. 4 , the top edges  34 ,  36  will tend to curl away one from the other as illustrated in  FIG. 1 , but with one ply remaining smooth. 
         [0038]      FIG. 1C  illustrates yet another embodiment of the invention wherein nip  20  is defined by two smooth rollers  70 ,  72 , each having a smooth surface  73 . Preferably, the plies  26 ,  28  passing nip  20  of  FIG. 1C  are elevated so the plies are squeezed between respective smooth surfaces  73  in mouth regions  32 , but in a part of region  32  spaced from edges  34 ,  36  as shown in  FIG. 5 . Edges  34 ,  36  are thus curled, as shown in  FIG. 5 , one away from the other to form an open area  74  between plies  26 ,  28  facilitating further opening of the pouch mouth by an air stream as desired. This curl, accompanied by the conditioning of the plies  26 ,  28  in the nip, facilitates and enhances opening of such a pouch. This embodiment then, in use, is partly illustrated in  FIG. 6  with the exception that the plies  26 ,  28  in mouth region  32  are smooth, rather than crimped in a pattern as in  FIG. 6 . 
         [0039]    It will be appreciated that while nip  20  is shown in the embodiments herein formed by two opposed rotatable rollers, the invention contemplates a single roller forming a nip with opposed back-up surfaces of a variety of expedients. 
         [0040]    Accordingly, the invention contemplates a pouch having a pressed or squeezed mouth region in either a pattern format or smooth to strengthen the mouth and to facilitate opening reliably and consistently. Pouch plies can be squeezed to cause an edge curl widening the mouth for opening. Preferred apparatus includes a roller defined nip for imparting a crimp to a pouch mouth region and to squeeze the pouch mouth region to form a curl in the mouth edges whether or not a crimped pattern is formed in the pouch. Rollers can have crimped or smooth peripheries. A preferred method according to the invention includes running pouch plies through a nip in the pouch mouth region either to impart a crimp thereto to facilitate mouth opening and hold open or to cause mouth edges to curl and facilitate mouth opening, or both. 
         [0041]    These and other alternatives and modifications will be readily apparent to one of ordinary skilled in the art without departing from the scope of the invention and applicant intends to be bound only by the claims which are made in this application.