Patent Publication Number: US-11034119-B2

Title: Bottom gusset package with folded gusset

Description:
TECHNICAL FIELD 
     The present invention relates generally to packages formed from polymeric film webs, and more particularly to a bottom-gusseted package including a folded bottom gusset positioned transversely of a longitudinal axis of the package, with the configuration of the package, and its method of formation, permitting use with associated form, fill, and seal equipment. 
     BACKGROUND OF THE INVENTION 
     Packages formed from plastic, polymeric film material have found widespread application in the market place for convenient and efficient packaging of all manner of food and non-food products. Packages of this nature typically are formed by folding and sealing a web of polymeric material to form a package body having front and rear package panels, with the package panels joined to each other at margins thereof. Depending upon the method of formation, the front and rear package panels may be joined to each other either by folded portions of the package body, or at seals (typically heat seals) joining the package panels to each other. 
     Non-gusseted packages of this type are sometimes referred to as “pillow packs”, and do not include either side gussets or top or bottom gussets. However, for many applications it is desirable to form a gusseted package that is, providing the package with inwardly-extended, pleat-like gussets at one or more margins of the package body. For example, side-gusseted packages include inwardly extending side gussets at opposite lateral sides of the package body, which side gussets join respective lateral edges of the front and rear package panels to each other. 
     For some applications, it is especially desirable to provide a bottom-gusseted package, that is, a package having an inwardly extending gusset at the bottom of the package body. By virtue of the breadth and stability provided by the bottom gusset, packages of this nature can frequently be configured to be self-standing, promoting efficient display for consumer selection. 
     Heretofore, bottom-gusseted packages have typically been formed by pleating a web of polymeric material in a direction parallel to the longitudinal axis of the web. Suitable ploughs and forming guides shape and configure the polymeric web as it moves longitudinally, including formation of a continuous, inwardly extending bottom gusset in the web material. Subsequently, suitable seals are formed transversely of the web to define individual package bodies, each including front and rear package panels, with each including a bottom gusset. Individual package bodies are formed by cutting the web of material at the transversely extending seals, with the contents of each package deposited therein either before or after cutting of the web into individual packages. 
     As will be appreciated by this typical formation technique, the height or vertical dimension of each package body is equal to approximately one-half of the width of the polymeric web, less the dimension of the bottom gusset. As a consequence, the maximum height of any package being formed is essentially limited by the maximum width of the web of polymeric material which the forming equipment is capable of handling. 
     The present invention contemplates a bottom-gusseted package, and a method of formation, which addresses the shortcomings in the conventional forming of bottom-gusseted package. This is achieved by forming each package with a bottom gusset positioned transversely of the longitudinal axis of the polymeric film web and each package, with the bottom gusset having at least one fold therein. The bottom-gusseted packages of any selected height can be readily and efficiently formed. 
     SUMMARY OF THE INVENTION 
     A bottom-gusseted package embodying the principles of the present invention comprises a package body formed from a flexible web having a longitudinal axis. The flexible web is folded to define a front package panel and a rear package of the package body. The front and rear package panels are joined to each other at respective lateral side margins of the package body, with the flexible web being joined to itself along a seam which extends parallel to the longitudinal axis of the flexible web. 
     A package formed in accordance with the present invention includes a bottom gusset positioned between the front and rear package panels, with the bottom gusset extending upwardly and inwardly from the lower edges of the front and rear package panels. The bottom gusset is positioned within the package body transversely of the longitudinal axis of the package body, and transversely of the longitudinal axis of the flexible web from which the package body is formed. This permits a package body to be very efficiently formed at any selected height. 
     Efficient formation of the present package is facilitated by arranging the bottom gusset within the package such that each gusset is folded within the package body, along a fold line that extends parallel to the longitudinal axis of the package. In certain illustrated embodiments, this is achieved by folding at least one end of each individual sleeve which forms the bottom gusset of the package. Normal manufacturing tolerances and variations are readily accommodated while ensuring formation of a package in which the contents are sealed, and the bottom gussets opens as intended. 
     In an alternative embodiment, each gusset is folded to form each package with a pair of bottom gussets, with each package preferably including a pair of inwardly extending side gussets which extend between the pair of bottom gussets. 
     In accordance with the present invention, a method of making bottom-gusseted packages, comprises the steps of providing a flexible web of material having a longitudinal axis, which web provides the body of each package being formed. Suitable polymeric material can be employed by virtue of its liquid-impermeable characteristics, and heat-sealing capabilities. 
     The present method further comprises providing a plurality of folded, individual sleeves, with each sleeve eventually forming the bottom gusset of the package. The individual sleeves can be cut from a folded, sleeve-forming web. The individual sleeves are joined to the flexible web in spaced apart relationship longitudinally thereof. The spacing between the individual sleeves corresponds to the length of each of the bottom-gusseted packages being formed. 
     To permit heal-sealing formation of the present package, the exterior surface of each individual sleeve is readily heat-sealable to the flexible web which forms the package body. In contrast, the inside surface of each sleeve is non-heat sealable to itself, thus facilitating formation of a bottom gusset which spreads or opens to permit the packages being formed to be generally self-standing. Thus, the interior surface of the folded sleeve has heat-sealing characteristics that differ from the heat-sealing characteristics of the exterior surface of the sleeve. To this end, the sleeve-forming web can be made from a material which is different than the flexible web which forms the package body. 
     Package formation next includes folding the flexible web of material, and joining the lateral margins thereof to form a folded flexible web. The effects formation of a package body for each of the bottom-gusseted packages, including a front package panel and a rear package panel joined at opposite side margins thereof. 
     Notably, attendant to the folding step, each individual sleeve within the folded web is also folded. As will described, folding of one or both ends of each individual, gusset-forming sleeve permits efficient placement of the individual sleeves on the flexible web, and facilitates heat-sealing the web and sleeve to close the interior of the package being formed. 
     Attendant to package filling, such as on a form, fill and sealing apparatus, the folded, flexible web is cut at intervals each corresponding in length to the length of each bottom-gusseted package. Each individual sleeve provides a bottom gusset for a respective one of the packages being formed. While the individual sleeves can be joined to the flexible web in conjunction with package filling, it is contemplated that the gusset-forming sleeves can be joined to the flexible web apart from the filling process, with a flexible web having such “pre-applied” gusset-forming sleeves rolled for subsequent use with filling machinery. 
     Attendant to cutting the folding web into individual packages, the individual sleeves providing each bottom gusset can be substantially simultaneously cut, so that a portion of each individual sleeve provides: (1) the bottom gusset for one of the packages being formed, and (2) a top sleeve portion for an adjacent one of the packages being formed. The top sleeve portion can be configured to include a dispensing feature, an upper package seal, and/or a recloseable fastener feature. However, it is within the purview of the present invention to form packages with a bottom gusset only, without a top sleeve portion. 
     The folding step can include folding the flexible web of material generally at the longitudinal axis thereof, so that each of the individual sleeves extends generally between said longitudinal axis and the joined lateral margins of said flexible web. By formation in this manner, each of the individual sleeves is folded only at one end thereof. 
     If desired, each of the individual sleeves can be provided with a length which is greater than the width of the folded web of flexible material, such that the folding step includes folding each end of each of the individual sleeves. However, in some instances, due to normal manufacturing tolerances, only one end of each individual sleeve is folded. 
     The present method contemplates forming at least one side seal joining the front and rear package panels to the to the individual sleeve, including joining the front and rear package panels to each other above the bottom gusset. A pair of side seals can be formed which join the front and rear package panels to each individual sleeve, wherein the side seals extend above and overlap the respective individual sleeve and join the front and rear package panels to each other. 
     Another aspect of the present invention contemplates that the step of joining the lateral margins of the flexible web includes forming a fin seal comprising two plies of the flexible web material. The fin seal can be folded against the rear package panel, so a thickness of package at the fin seal is substantially equal to a thickness of each package at the folded ends of the individual sleeve providing the bottom gusset of the package. Heat-sealing formation is desirably facilitated. 
     In another aspect of the invention, the flexible web of material can be formed to include a pair of inwardly extending side gussets. In this embodiment, the folding step includes folding each of the individual sleeves to extend adjacent to itself within the folded flexible web to thereby form each of the packages with a pair of bottom gussets adjacent to each other. The method includes joining inner edge portions of bottom gussets to each other to close the interior of the package, with the pair of side gussets each extending between the pair of bottom gussets. 
     As noted, it is presently contemplated that the folded sleeve-forming web from which the bottom gussets are formed has an inside surface of which does not heat-seal to itself. Since package formation, and advancement through the form, fill and seal machine can sometimes orient the bottom gusset in the “leading” direction, in can be desirable to close the individual sleeves against opening during such advancement. This can be achieved by closing each of the individual sleeves prior to joining the individual sleeves to the flexible web of material. 
     Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagrammatic, front elevational view of a bottom-gusseted package having a folded gusset embodying the principles of the present invention; 
         FIG. 2  is a diagrammatic bottom plan view of the package shown in  FIG. 1  illustrating the bottom gusset in an opened condition; 
         FIG. 3  is a diagrammatic top plan view of the package shown in  FIG. 1 ; 
         FIG. 4  is a partial, diagrammatic front elevational view showing formation of a bottom-gusseted package having a folded gusset embodying the principles of the present invention; 
         FIG. 5  is a partial, diagrammatic side elevational view taken generally along lines  5 - 5  in  FIG. 4 ; 
         FIG. 6  is a diagrammatic, cross-sectional view taken generally along lines  6 - 6  in  FIG. 4 ; 
         FIG. 7  is a diagrammatic view illustrating formation a method of forming a bottom-gusseted package in accordance with the present invention; 
         FIG. 8  is a partial, diagrammatic front elevational view illustrating formation of an alternative embodiment of a bottom-gusseted package having a bottom gusset folded at only one end thereof embodying the principles of the present invention; 
         FIG. 9  is a partial, diagrammatic side elevational view take generally along lines  9 - 9  in  FIG. 8 ; 
         FIG. 10  is a diagrammatic cross-sectional view taken generally along lines  10 - 10  in  FIG. 8 ; 
         FIG. 11  is a diagrammatic front elevational view of this embodiment of the bottom-gusseted package having a bottom gusset folded at only one end thereof; 
         FIG. 12  is a diagrammatic bottom plan view of the package shown in  FIG. 11  illustrating the bottom gusset in an opened condition; 
         FIG. 13  is a diagrammatic top plan view of the package shown in  FIG. 11 ; 
         FIG. 14  is a diagrammatic view illustrating formation of the package shown in  FIGS. 8-13 , in accordance with the present invention; 
         FIG. 15  is a diagrammatic perspective view illustrating a further embodiment of the present bottom-gusseted package, including a bottom gusset which is folded to form a pair of bottom gussets, with the package including a pair of inwardly extending side gussets; and 
         FIG. 16  is a diagrammatic view illustrating formation of the package illustrated in  FIG. 15 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described the presently preferred embodiments, with the understanding that the present disclosure should be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiments illustrated. 
     U.S. Pat. Nos. 4,909,017, 4,617,683, 5,902,047, 6,971,794, and 8,182,407, and U.S. Patent Publications No. 2014/0294326, and No. 2014/0161373, illustrate various package constructions and formation methods, and are all hereby incorporated by reference. 
     The present invention is directed to a “stand-up” style of package, which includes a bottom gusset which can be opened or splayed apart to permit the package to assume a generally self-standing, upright configuration. This type of package facilitates convenient retail display and use by consumers. 
     Notably, and as will further described, a package embodying the present invention can be formed by positioning a gusset-forming sleeve transversely of a flexible web of material from which the package is formed. Formation in this fashion very desirably permits the package to be used in conjunction with widely-used form, fill and sealing machinery, thus permitting versatile and cost-effective use of the package. Packages can be substantially entirely formed in connection with package filling, but it is contemplated that rolls of packaging material can be formed which have gusset-forming sleeves “pre-applied” thereto for subsequent use with filling machinery. 
     With reference to  FIGS. 1-7 , a bottom-gusseted package  10  embodying the principles of the present invention comprises a package body formed from a flexible web  12  having a longitudinal axis. The flexible web  12  is folded to define a front package panel  14  and a rear package  16  of the package body. The front and rear package panels  14 ,  16  are joined to each other at respective lateral side margins of the package body, with the flexible web  12  being joined to itself along a longitudinal seam  18  which extends parallel to the longitudinal axis LA of the flexible web. 
     The package  10  formed in accordance with the present invention includes a bottom gusset  20 , including folded ends  21 , positioned between the front and rear package panels  14 ,  16 , with the bottom gusset  20  extending upwardly and inwardly from the lower edges of the front and rear package panels. The bottom gusset  20  is positioned within the package body transversely of the longitudinal axis of the package body, and transversely of the longitudinal axis of the flexible web  12  from which the package body is formed. This permits a package body to be very efficiently formed at any selected height. 
     In this embodiment, efficient formation of the package  10  is facilitated by arranging the bottom gusset  20  within the package such that at least one end  21  of the gusset  20  is folded within the package body. This is achieved by folding at least one end of each individual sleeve which forms the bottom gusset of the package. Normal manufacturing tolerances and variations are readily accommodating while ensuring formation of a package  10  in which the contents are sealed, and the bottom gusset  20  opens as intended. 
       FIG. 7  diagrammatically illustrates a method of making bottom-gusseted packages accordance with the present invention. The method includes providing the flexible web  12  of material having a longitudinal axis. Suitable polymeric material can be employed by virtue of its liquid-impermeable characteristics, and heat-sealing capabilities. 
     The present method further comprises providing a plurality of folded, individual sleeves  26 , with each sleeve  26  eventually forming the bottom gusset  20  of the packages  10 . The sleeves  26  can be cut from a folded web of sleeve-forming material. The individual sleeves  26  are joined to the flexible web  12  in spaced apart relationship longitudinally thereof. The spacing between the individual sleeves  26  corresponds to the length of each of the bottom-gusseted packages  10  being formed. 
     To permit heal-sealing formation of the present package, the exterior surface of each folded sleeve  26  is readily heat-sealable to the flexible web  12 . In contrast, the inside surface of each of the folded, individual sleeves  26  is non-heat sealable to itself, thus facilitating formation of a bottom gusset  20  which spreads or opens to permit the packages  10  being formed to be generally self-standing. Thus, the interior surface of the folded sleeve  26  has heat-sealing characteristics that differ from the heat-sealing characteristics of the exterior surface. To this end, the sleeve-forming web from which sleeves  26  are formed can be made from a material which is different than the flexible web which forms the package body. 
     Package formation includes the folding flexible web of material  12 , and joining the lateral margins LM 1 , LM 2  thereof to form a folded flexible web. This effects formation of a package body for each of the bottom-gusseted packages  10 , including a front package panel  14  and a rear package panel  16  joined at opposite side margins thereof. 
     Notably, in this embodiment, attendant to the folding step, at least one end of each individual sleeve  26  within the folded web is also folded. As will described, folding of the ends of each individual, gusset-forming sleeve  26  permits efficient placement of the individual sleeves on the flexible web  12 , and facilitates heat-sealing the web  12  and sleeve  26  to close the interior of the package being formed. If desired, each of the individual sleeves  26  can be provided with a length which is greater than the width of the folded web of flexible material, such that the folding step includes folding each end of each of the individual sleeves. However, depending upon design considerations and normal manufacturing tolerances, only one end on each sleeve  26  can be folded, while the other end remains unfolded. 
     Attendant to package filling, such as on a form, fill and sealing apparatus, the folded, flexible web  12  is cut at intervals each corresponding in length to the length of each bottom-gusseted package  10 . Each individual sleeve  26  provides a bottom gusset  20  for a respective one of the packages  10  being formed. 
     Attendant to cutting the folded web  12  into individual packages  10 , the individual gusset-forming sleeve  26  can be cut substantially simultaneously, so that each individual sleeve provides: (1) the bottom gusset  20  for one of the packages being formed, and (2) a top sleeve portion  28  for an adjacent one of the packages  10  being formed. The top sleeve portion  28  can be configured to include a dispensing feature, an upper package seal, and/or a recloseable fastener feature. However, it is within the purview of the present invention that the invention be practiced for forming packages with a bottom gusset only, without a top sleeve portion. 
     The folding step can include folding the flexible web of material generally at the longitudinal axis thereof, with the individual sleeves  26  positioned to extend generally between the longitudinal axis and the joined lateral margins of the flexible web  12 . By formation in this manner, each of the individual sleeves  26  is folded only at one end thereof. Formation in this fashion in shown in the embodiment illustrated in  FIGS. 8-14 . In this embodiment, the longitudinal seam  18  of the package is positioned at one side margin thereof. 
     The present method contemplates forming at least one side seal joining the front and rear package panels to the individual sleeve at respective ends thereof, including joining the front and rear package panels  14 ,  16  to each individual sleeve  26  at respective ends thereof, wherein the side seals  30  extend above and overlap the respective individual sleeve and join the front and rear package panels to each other. 
     In both of the embodiments illustrated in  FIGS. 1-11 , side seals  30  are provided at the opposite ends of each bottom gusset  20 , with the side seals configured to join the front and rear package panel  14 ,  16  to each other above the respective bottom gusset. Depending upon the specific positioning of each bottom gusset  20  within the package, which may vary due to normal manufacturing tolerances, one or both of the side seals  30  of each package can join the front and rear package panels to each other laterally adjacent to the bottom gusset. 
     Another aspect of the present invention contemplates that the step of joining the lateral margins of the flexible web  12  to form the longitudinal seal  18  of the package as a fin seal, best shown in  FIGS. 2, 3 and 6 , comprising two plies of the flexible web material. The fin seal can be folded against the rear package panel  16 , so a thickness of package at the fin seal is substantially equal to a thickness of each package at the folded ends of the individual sleeve providing the bottom gusset  20  of the package. As will be evident from  FIG. 3 , heat-sealing formation is desirably facilitated. 
     Attendant to package formation and filling, end seals  32 ,  34  can be formed respectively closing and sealing the top and bottom of each package  10 . When the package  10  is formed with a top sleeve portion  28 , the end seal  32  at the top of the package can be formed to substantially surround the bottom and sides of the top sleeve portion  28 . Since the inner surfaces of the top sleeve portion are not heat-sealable, access to the contents of the package can be effected by splitting and separating the two layers of sleeve material which form the top sleeve portion. 
     With reference now to  FIGS. 15 and 16 , in another embodiment of the invention, the flexible web of material  12  can be formed to include a pair of inwardly extending side gussets  40 . In this embodiment, the folding step includes folding each of the individual sleeves  26  to extend adjacent to itself within the folded flexible web  12  to thereby form each of the packages  10  with a pair of bottom gussets  20 ,  20  adjacent to each other. The method includes joining inner edge portions of bottom gussets to each other at  21  to close the interior of the package. 
     A method of making bottom-gusseted packages in accordance with this aspect of the present includes forming the pair of inwardly extending side gussets  40  at respective opposite edges of said front and rear package panels  14 ,  16 , with the pair of side gussets each extending between the pair of bottom gussets  20 ,  20 . In this embodiment, the lateral margins of the flexible web are joined at seam  18  at one of the side gussets  30  to join an edge of one of the front and rear package panels  14 ,  16  to the side gusset. 
     As noted, it is presently contemplated that the folded sleeve-forming web from which the bottom gussets are formed has an inside surface of which does not heat-seal to itself. Since package formation, and advancement through the form, fill and seal machine can sometimes orient the bottom gusset in the “leading” direction, in can be desirable to close the individual sleeves against opening during such advancement. This can be achieved by closing each of the individual sleeves prior to joining the individual sleeves to the flexible web of material 
     From the foregoing, it will be observed that numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated herein 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.