Patent Publication Number: US-2023142122-A1

Title: Bag forming apparatus

Description:
TECHNICAL FIELD 
     The present invention relates to bags, such as paper bags, and more particularly to a bag forming apparatus for forming the bottom of such bags. 
     BACKGROUND 
     Paper bags are used for a wide variety of applications, including the storage and transportation of goods or waste. Many conventional paper bags are formed from single-ply kraft paper using complex machinery. Generally, such machinery first folds the sheet and adheres at least two of its edges to form a tube. Then an open end of the tube is folded via the complex machinery to form a bottom of the bag. The bag can then be opened such that the bottom of the bag is flat, generally planar and generally perpendicular to adjacent side walls of the bag. Such bag forming machinery typically is large, expensive, and is designed to mass produce such bags for later point of use at a remote location. 
     SUMMARY 
     The present disclosure describes a bag forming apparatus with a simplified construction that enables a user to manually form a flat bottom of a bag, such as at the point of use. 
     The bag forming apparatus may be designed as a relatively small fixture in a retail sales location, a packaging facility, or an assembly line, for example, in which a user forms the flat bottom of the bag from a tubular segment just prior to its use. 
     The simplified construction of the bag forming apparatus may make it inexpensive to manufacture and reproduce, and thus may be deployed at one or more point-of-use locations. The bag forming apparatus also may be easily transportable for further facilitating its point-of-use functionality. 
     The bag forming apparatus may be particularly useful for forming the flat bottom of multi-walled bags, and more particularly multi-walled materials that are difficult to handle and fold in conventional bag-folding machinery. Such multi-walled materials may include cushioning or insulating materials, such as slit sheet materials or other open-celled materials, that are particularly difficult to handle and fold in an automated machine. 
     According to an aspect of the present disclosure, a bag forming apparatus for forming a bottom of a bag includes: a base; opposing sidewalls, each sidewall being operably coupled at a lower portion thereof for enabling movement of the sidewalls relative to each other; a top operably coupled to an upper portion of each of the sidewalls, the top having an intermediate pivot axis between the sidewalls, wherein the top is pivotable about the pivot axis to move between a collapsed state and an expanded state; where in the collapsed state, the upper portions of the respective sidewalls are closer together and the top extends upright relative to the base to form a tip that is configured for being received in an opening of the bag; and where in the expanded state, the upper portions of the respective sidewalls are spaced further apart and the top extends horizontally relative to the base to form a platform that is configured for forming the flat bottom of the bag. 
     According to another aspect of the present disclosure, a bag forming apparatus for forming a paper bag having a flat bottom includes: a base; first and second sidewalls that extend upright relative to the base, each of the first and second sidewalls being hinged for pivotable movement relative to the base and relative to each other; and a top having a first top portion that is hinged to the first sidewall, and a second top portion that is hinged to the second sidewall, the first and second top portions being hinged together at an intermediate pivot location between the first and second sidewalls for enabling the first and second top portions to pivot relative to each other between a collapsed state and expanded; where in the collapsed state, the first and second top portions are inclined relative to the base to form a tip that is configured to facilitate the top and sidewalls to be received in an opening of the bag; and where in the expanded state, the first and second top portions are horizontal relative to the base to form a platform that is configured to facilitate formation of the flat bottom of the bag. 
     According to another aspect of the present disclosure, a method of forming a flat-bottomed bag includes the following steps: (i) placing a bag preform over a top and opposing sidewalls of a bag forming apparatus that is in a collapsed state, where in the collapsed state the top of the apparatus extends upright relative to a base of the apparatus to form a tip that is received in an opening of the bag preform during the placing step; (ii) engaging the top of the apparatus, where the engaging step causes the top to pivot about an intermediate portion of the top to an expanded state, where in the expanded state the top extends horizontally relative to the base of the apparatus to form a platform; and (iii) forming a flat bottom of the bag preform on the platform to thereby form the flat-bottomed bag. 
     The following description and the annexed drawings set forth certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features according to aspects of the invention will become apparent from the following detailed description when considered in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The annexed drawings, which are not necessarily to scale, show various aspects of the present disclosure. 
         FIG.  1    is a perspective top, front view of an exemplary bag forming apparatus according to an embodiment of the present disclosure. 
         FIG.  2    is a front view of the bag forming apparatus shown in an exemplary collapsed state. 
         FIG.  3    is a front view of the bag forming apparatus shown in an exemplary expanded state. 
         FIG.  4    is an enlarged perspective view showing an inside portion of the bag forming apparatus. 
         FIG.  5    shows an exemplary multi-layered paper bag that may be used with the bag forming apparatus in  FIG.  1    for forming a flat bottom of the bag. 
         FIGS.  6 - 10    show exemplary method steps of forming the flat bottom of the bag in  FIG.  5    with the bag forming apparatus in  FIG.  1   . 
         FIGS.  11 - 16    show various alternative embodiments of exemplary bag forming apparatuses according to the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The principles and aspects of the present invention have particular application to forming the flat bottom of bags made of multi-layered materials, and thus will be described below chiefly in this context. The principles and aspects of the present invention may be applicable to forming other suitable materials, including single-ply materials such as kraft paper and the like, where it is desirable to provide a simple apparatus that may be deployed at the point of use for such bags. 
     As described above, flat-bottomed paper bags are currently formed with large and complex machines, typically limited to a manufacturing facility. The bag-forming apparatus described here is compact and potentially portable, allowing for installation at the point of use. In exemplary embodiments the bag-forming apparatus is not automated, however, and requires manual labor, so it may not be suitable for high-volume applications. 
     Referring now to the drawings in detail, and initially to  FIGS.  1 - 4   , the drawings show an exemplary bag-forming apparatus  10  for forming a flat bottom of a bag. The bag-forming apparatus  10  generally includes a base  12 , first and second sidewalls  14 ,  16  extending upwardly relative to the base  12 , and a top  18  that is operably coupled to each of the first and second sidewalls  14 ,  16 . As described in further detail below, the top  18  is deployable between a collapsed state that forms a relatively narrow tip configured for ready receipt in an opening of the bag or a bag preform, and an expanded state that forms a platform for forming the bottom of the bag. 
     The base  12  may be any suitable structure or structures that support the sidewalls  14 ,  16 , the top  18 , and any other components of the apparatus  10 . In the illustrated embodiment, the base  12  includes a flat plate having a quadrilateral (e.g., rectangular) shape. In exemplary embodiments, the base  12  is a single unitary structure, with each of the sidewalls  14 ,  16  being operably coupled to the base  12 . In other embodiments, the base  12  may include multiple discrete base parts, with each sidewall  14 ,  16  being operably coupled to a respective base part. The apparatus  10  may be attached to the ground via the base  12 , or the apparatus  10  may be configured for transport to different point of use locations. 
     The sidewalls  14 ,  16  may have any suitable configuration for supporting the top  18  of the apparatus  10  at an elevated position relative to the base  12  when forming the bottom of the bag. As shown, the sidewalls  14 ,  16  extend upright to an elevation that is a sufficient distance above the base  12  that will permit the sides of the bag or bag preform to extend downwardly over the sidewalls  14 ,  16  when the bottom of the bag is being formed on the top  18  (as shown in  FIGS.  6 - 8   , for example, and described in further detail below). As a result, the length of the sidewalls  14 ,  16  generally approximates the height of the finished bag. 
     In the illustrated embodiment, the sidewalls  14 ,  16  are formed by continuous flat plates that extend along a majority of the lateral sides  20 ,  21  of the base  12  in a depth direction (Z). In exemplary embodiments, the sidewalls  14 ,  16  are a single unitary piece, however, in other embodiments the sidewalls  14 ,  16  may be formed by multiple discrete or integrated pieces. 
     In exemplary embodiments, each of the first and second sidewalls  14 ,  16  are hinged for pivotable movement relative to the base  12  and relative to each other between the collapsed state and the expanded state. As shown in the illustrated embodiment, the sidewalls  14 ,  16  may be hinged at their respective lower portions  22 ,  24  with respective lower hinges  26  that pivotably couple the sidewalls  14 ,  16  to spaced apart locations, such as at opposite sides  20 ,  21  of the base  12 . The lower hinges  26  may be any suitable hinges for providing such pivotable movement between the sidewalls and the base. For example, the lower hinges  26  may be discrete parts that are operably coupled to the respective sidewalls  14 ,  16  and to the base  12 ; or the lower hinges  26  may form one or more parts of one or more of the sidewalls  14 ,  16  or one or more parts of the base  12 , or a combination thereof. 
     As shown, the top  18  of the apparatus  10  includes a first top portion  28  that is operably coupled to an upper portion  30  of the first sidewall  14 , and a second top portion  32  that is operably coupled to an upper portion  34  of the second sidewall  16 . In exemplary embodiments, the first and second top portions  28 ,  32  are hinged at their respective lateral edges  36 ,  38  to the respective first and second sidewalls  14 ,  16  using respective upper hinges  40 . The upper hinges  40  may be any suitable hinges for providing relative pivotable movement between the sidewalls  14 ,  16  and the top  18  as they move relative to one another between the collapsed state and the expanded state. For example, the upper hinges  40  may be discrete parts that are operably coupled to the sidewalls  14 ,  16  and the respective first and second top portions  28 ,  32 ; or the upper hinges  40  may form one or more parts of one or more of the sidewalls  14 ,  16  one or more parts of the top  18 , or a combination thereof. 
     In exemplary embodiments, the first and second top portions  28 ,  32  are hinged together at an intermediate pivot location  42  between the first and second sidewalls  14 ,  16 . This hinged configuration enables the first and second top portions  28 ,  32  to pivot relative to each other between the collapsed state (as shown in  FIG.  2   , for example) and the expanded state (as shown in  FIG.  3   , for example). In the illustrated embodiment, the first and second top portions  28 ,  32  are hinged together at the intermediate pivot location  42  using a suitable intermediate hinge  44 . The intermediate hinge  44  may be a discrete part that is operably coupled to the first and second top portions  28 ,  32 ; or the intermediate hinge  44  may form one or more parts of the first and second top portions  28 ,  32 . As described in further detail below, pivoting of the first and second top portions  28 ,  32  relative to each other about a pivot axis  45  of the intermediate hinge  44  will result in the first and second sidewalls  14 ,  16  pivoting relative to each other via the respective upper and lower hinges  40 ,  26 . This, in turn, may enable the apparatus  10  to have a relatively slender form in its collapsed state for enabling placement of the bag or bag preform over the apparatus, and a relatively broad form in its expanded state for enabling formation of the bottom of the bag. 
       FIG.  2    shows the apparatus  10  in an exemplary collapsed state. In moving to the collapsed state, the first and second top portions  28   32  pivot toward each other about the intermediate hinge  44  such that they extend upright relative to the base  12  and cooperate with the sidewalls  14 ,  16  to form a relatively narrow tip  48 . In the illustrated embodiment, the tip  48  is formed at the intermediate pivot location  40  which is at an elevation above the first and second sidewalls  14 ,  16 . The tip  40  may have any suitable configuration for facilitating insertion into an opening of the bag or bag preform. For example, as shown in the illustrated embodiment, the first and second top portions  28 ,  32  may be inclined upwardly (in a height direction, Y) and inwardly (in a width direction, X) toward each other, such that the tip  40  has a generally pointed triangular profile. Alternatively, the tip  40  may have a more rounded or squared profile. Any suitable number of intermediate hinges  44  or top portions (e.g.,  28 ,  32 ) may be employed to achieve the desired profile of the tip  40  when the apparatus  10  is in the collapsed state. 
     As shown, when the apparatus  10  is in the collapsed state, the respective upper portions  30 ,  34  of the first and second sidewalls  14 ,  16  are located closer to each other by virtue of their connection to the top  18  via the upper hinges  40 . In exemplary embodiments, the sidewalls  14 ,  16  are permitted to laterally pivot in this manner by virtue of their connection to the base  12  via the lower hinges  26 . Alternatively or additionally, the sidewalls  14 ,  16  may be configured to flex to accommodate such movement, for example if they are non-pivotably fixed to the base  12 . In the illustrated embodiment, the first and second sidewalls  14 ,  16  are inclined upwardly in the height direction (Y) and inwardly toward each other in the width direction (X) to provide a relatively slender profile for the apparatus  10  in the collapsed state. This slender profile provided by both the top and sidewalls  14 , 16  further facilitates placing the bag or bag preform over the apparatus  10 . Other suitable configurations for the sidewalls  14 ,  16  are possible in the collapsed state, such as extending upright perpendicularly to the base  12 ; or extending upwardly and outwardly from each other, for example. 
     In exemplary embodiments, the apparatus  10  may further include one or more upright supports  50  that are arranged in the space between the first and second sidewalls  14 ,  16 . As shown, the upright supports  50  are configured to engage and support the opposing sidewalls  14 ,  16  when the apparatus  10  is in the collapsed state, which helps to prevent the apparatus  10  from falling down. In the illustrated embodiment, the upright supports  50  each have tapered lateral surfaces  52 ,  54  that correspond with the inward incline of the opposing sidewalls  14 ,  16  in the collapsed state. In this manner, the upright supports  50  may align with and engage each of the sidewalls  14 ,  16  along a majority of the tapered support surfaces  52 ,  54  when in the collapsed state. In the illustrated embodiment, the apparatus  10  includes two upright supports  50  that are spaced apart in the depth direction (Z) of the apparatus, although any suitable number of supports  50  may be provided depending on the number or size or a combination thereof of the sidewalls  14 ,  16 , for example. 
     Referring to  FIG.  4   , the apparatus  10  may further include a biasing member  56  that is operably coupled to each of the first and second sidewalls  14 ,  16 . The biasing member  56  may be configured to bias the apparatus  10  to the collapsed state, so as to provide an automatic return to the collapsed state after forming the bottom of the bag in the expanded state. The biasing member  56  may be any suitable structure configured to bias the apparatus  10  to the collapsed state. In the illustrated embodiment, for example, the biasing member  56  includes one or more coil springs  56  interposed between the first and second sidewalls  14 ,  16 . The coil springs  56  are attached to the respective inner surfaces  58 ,  59  of the sidewalls  14 ,  16  and urge them inwardly toward each other. This, in turn, urges the first and second top portions  30 ,  34  of the sidewalls  14 ,  16  to pivot toward each other about the intermediate hinge  44  to form the tip  48  in the collapsed state. 
     Referring to  FIG.  3   , the apparatus is shown in an exemplary expanded state. As shown in the expanded state, the first and second top portions  28 ,  32  are aligned with the intermediate hinge  44  in a common horizontal plane to form a platform  60 . The platform  60  is facilitates formation of the bottom of the bag (as shown in  FIGS.  8  and  10   , for example, and described in further detail below). 
     As shown, when the top  18  pivots to the expanded state, the respective upper portions  30 ,  34  of the first and second sidewalls  14 ,  16  hinged to the top  18  move outwardly away from each such that they are spaced further apart when compared to the collapsed state. In exemplary embodiments, the sidewalls  14 ,  16  are permitted to laterally pivot in this manner by virtue of their connection to the base  12  via the lower hinges  26 . Alternatively or additionally, the sidewalls  14 ,  16  may be configured to flex to accommodate such lateral outward movement, for example if they are non-pivotably fixed to the base  12 . In the illustrated expanded state, the first and second sidewalls  14 ,  16  are inclined upwardly (in the height direction, Y) and outwardly away from each other (in the width direction, X). Such a configuration maintains the relatively narrow lower portion of the apparatus  10 , which may help prevent tearing of the upper part of the bag during the bottom-forming process. Other suitable configurations for the sidewalls  14 ,  16  are possible in the expanded state, such as extending upright perpendicularly to the base  12 ; or extending upwardly and inwardly inclined toward each other, for example. 
     In exemplary embodiments, the apparatus  10  may include suitable stops for restricting the pivotable movement of the top  18  or the sidewalls  14 ,  16  or a combination thereof beyond predetermined positions or orientations. In the illustrated embodiment, for example, the first and second top portions  28 ,  32  have respective mating faces  62 ,  64  at the intermediate pivot location  40  which serve as stops. As shown, the respective mating faces  62 ,  64  are configured to engage each other when the apparatus  10  is in the expanded state, thereby restricting further pivotable movement of the top  18  beyond a horizontal position. Other suitable stops may be provided, such as overlapping projections, or the like. The intermediate hinge  44  also may include a stop. Alternatively or additionally, the first and second sidewalls  14 ,  16  also may include suitable stops for preventing movement of these members beyond desired orientations in the collapsed state or the expanded state or a combination thereof. 
     The top  18  of the apparatus  10  may have any suitable configuration for accommodating formation of the bottom of the bag. Generally, the shape of the platform  60  formed by the top  18  will correspond with the shape of the bottom of the bag. In the illustrated embodiment, for example, the first and second top portions  28 ,  32  each have a thin rectangular shape, which in the expanded state forms a larger rectangular shape. In addition, the exemplary first and second top portions  28 ,  32  have flat upper surfaces, and are configured to lie horizontally coplanar with each other when in the expanded state. Such an exemplary configuration of the top  18  forms a platform  60  with a flat upper surface  62  that, in turn, enables the bottom of the bag to be formed with a flat bottom surface. The flatness of the platform  60  may have a reasonable amount of variation and still provide a desired flatness for the bottom of the bag. Other suitable configurations of the platform  60  are possible, such as other polygonal shapes (e.g., square, triangular, trapezoidal, etc.); or the platform  60  may have a circular or oval shape. The platform  60  also may be provided with non-flat surfaces, such as a bulging (convex) upper surface for forming a dished bottom of the bag. 
     The components of the apparatus  10 , including the base  12 , sidewalls  14 ,  16 , top  18 , and supports  50  may be made from any suitable material (or combination of materials) to accommodate the functionality of those components. For example, such components of the apparatus  10  may be made from metals, plastics, composites, in various forms and combinations, which may be selected in a well-known manner. In exemplary embodiments, one or more of these components of the apparatus  10  may be made from lightweight and relatively inexpensive materials, such as sheet metal or plastic, for example. 
     The respective hinges of the apparatus  10 , including the lower hinges  26 , upper hinges  40 , and one or more intermediate hinges  44 , may be in the form of discrete parts that are operably coupled to their respective hinged parts. Non-limiting examples of such hinges include: butt hinges, barrel hinges, continuous hinges, pivot (knife) hinges, spring hinges, and the like. Alternatively or additionally, one or more of the respective hinges  26 ,  40 ,  44  may form a part of their respective hinged parts. For example, the intermediate hinge  44  may be a barrel-type hinge in which the first top portion  28  forms one part of a barrel, and the second top portion  32  forms the other part of the barrel, with a separate hinge pin extending through the barrel. Alternatively or additionally, one or more of the respective hinges  26 ,  40 ,  44  may be a living hinge, in which at least one of the hinged parts is integral and unitary with the hinge. For example, the first and second top portions  28 ,  32  may form a unitary top  18  with the intermediate hinge  44  being formed as a living hinge. Such living hinges may be particularly advantageous if the components of the apparatus are made of plastic or composites. Likewise, the sidewalls  14 ,  16  may be formed integrally with the top  18  or the base  12  or some combination thereof, with respective living hinge connections permitting pivotable movement between these connected components in the manner described above. 
     In some embodiments, one or more components of the apparatus, including the base  12 , the sidewalls  14 ,  16 , or the top  18 , may be made of flexible materials that can provide the desired amount of movement between the collapsed and expanded state without using hinged connections. For example, a flexible sidewall  14  or  16  or both could be non-movably coupled to the base  12  or the top  18  or some combination thereof, and still provide the desired lateral movement when the top  18  is deployed between the collapsed state and the expanded state. Likewise, flexible first and second top portions  28 ,  32  could be non-movably coupled together to provide the desired range of movement about a pivot axis (e.g.,  45 ) of the top  18  to transform between the tip  48  and the platform  60 . 
       FIGS.  5 - 10    illustrate an exemplary method of forming a flat bottom of a bag. Referring initially to  FIG.  5   , an exemplary bag preform  70  is shown having a tubular shape, with a closed end forming a pouch. The material of the bag or bag preform  70  may be any suitable material or combination of materials, including paper, plastic, and the like. In exemplary embodiments, the material forming the bag or bag preform  70  may include paper, such as kraft paper or the like. In exemplary embodiments, the bag material includes multiple plies or layers, which may be difficult to handle and fold in a conventional bag forming machine. In the illustrated embodiment, for example, the bag material includes a cushioning or insulating material  72 , such as an expanded or expandable slit-sheet material or other open-celled material. As shown, the cushioning or insulating material  72  may be bounded on at least one side, and preferably on both sides, with a continuous layer of sheet material  74 . In the illustrated embodiment, the continuous layers  74  are formed by kraft paper. The continuous layers  74  may be adhered to portions of the cushioning or insulating material layer  72  to contain and protect the cushioning or insulating material between the continuous layers  74 . 
     An exemplary expanded or expandable slit-sheet material may be made from one or more sheets of paper, such as kraft paper, in which each sheet has a plurality of spaced parallel rows of individual slits. The rows may extend transversely from one end of the paper material to the opposing end of said at least one sheet. Each of the rows is provided with interval spaces between consecutive slits and between each row. The plurality of slits extend transversely from one end of the paper material to the opposing end of the paper material with the slits in adjacent alternate rows each positioned adjacent the interval space between adjacent slits in the adjacent parallel row of slits. That is, the slits of one row are essentially opposite the spaces of the next row. Typically, the slits are arranged in a consistent, uniformly repeating pattern. The sheets are expandable by applying a force across the slits to open the slits and form a honeycomb-like pattern of openings in the expanded slit sheet material. The cushioning or insulating material formed by expanding the slit sheet may have an expanded thickness on the order of at least about ten times the unexpanded thickness of the sheet. The expanded slit sheet also is longer and narrower than the unexpanded slit sheet. An exemplary slit sheet material is described in U.S. Pat. No. 5,667,871, which is incorporated herein by reference. 
     As shown in  FIG.  5   , the bag preform  70  may be provided as a pouch that is bounded on at least three of its sides  75 ,  76 ,  77 , such as with seams  78 . On the fourth side  79 , the bag preform has an opening  80  that opens into an internal pocket of the pouch. The operator inserts the tip  46  of the bag-forming apparatus  10  into the opening  80  of the pouch, or the pouch is inserted over the tip  46  of the bag-forming apparatus  10  via the opening  80 . Other forms of bags or bag preforms also may be used with the exemplary bag forming apparatus  10 . For example, the bag preform may be bounded on at least one side to form an open-ended tube with two openings on opposing ends. With such a tube-style bag preform, the tip  48  of the apparatus  10  may be inserted into one of the openings, while the opposite open side may be closed while forming the bottom of the bag. The bag material may be provided as a continuous strip, which can be severed at a desired length or is weakened, such as with perforations, to facilitate tearing the appropriate length of bag material from the continuous strip when ready to form a bag. The bag material may be wound into the form of a roll, fan-folded into a rectangular stack, or discrete segments may be provided in a rectangular stack ready for use. 
       FIG.  6    shows placement of the pouch-type bag preform  70  over the bag forming apparatus  10 . As shown, the apparatus  10  is in its collapsed state and the tip  48  is inserted into the opening  80  of the bag preform  70 . In the illustrated embodiment, the bag preform  70  is oriented such that the length of the tip  48  in the depth direction (X) is aligned with the seam  78  opposite the opening  80 . The bag preform  70  is then pushed or pulled downwardly over the top  18  and opposing sidewalls  14 ,  16  until the tip  48  engages the inside bottom of the bag preform  70 . As shown, the apparatus  10  is configured to have a sufficient height to accommodate the height of the bag preform  70 . For different sized bags or bag preforms, different apparatus may be used, or the base  12  may be extended with a spacer to accommodate such longer sized bags, or the sides of the bag or preform may be bunched while the bottom of the bag is being formed. 
       FIG.  7    shows a user moving the bag preform  70  downwardly to deploy the top  18  from its collapsed state (with tip  48 ) into its expanded state (with platform  60 ). As shown, the user may press downwardly against the bottom of the bag preform  70 , which causes the first and second top portions  28 ,  32  to pivot about the intermediate hinge  44  to the expanded state. In the expanded state, the first and second top portions  28 ,  32  extend horizontally relative to the base  12  to form the platform  60 . As shown, the platform  60  may be sized to the bag preform  70 , such that in the expanded state the platform  60  does not tear the bag. Also in the expanded state, the first and second sidewalls  14 ,  16  pivot about the respective lower hinges  26  to extend outwardly relative to each other. This permits the opening  80  at the top of the bag preform  70  to remain somewhat relaxed without tearing, while the bottom part of the bag preform  70  remains somewhat taught for forming the bottom  82  of the bag. 
       FIG.  8    shows the user forming the flat bottom  82  of the bag on the platform  60 . Referring back to  FIG.  7   , when the user pushes the bottom of the bag preform  70  against the platform  60 , gussets  84  may be formed. As shown in  FIG.  8   , during the forming the flat bottom  82 , these gussets  84  are folded over and attached, such as with tape or other adhesive, to the bottom  82  of the bag preform  70 . Depending on the configuration of the platform  60  shape, additional gussets may be formed that also would be folded over to form the bottom of the bag as desired. 
       FIGS.  9  and  10    show a flat-bottomed bag that was formed from the bag preform  70  on the bag forming apparatus  10 . In the illustrated embodiment, the flat-bottomed bag (also referred to with reference numeral  70 ) has a rectangular flat bottom  82 . As shown, the flat-bottomed bag  70  with cushioning material  74  may now sit upright in a self-supported manner. This, in turn, may make it easier to fill the flat-bottomed bag  70 . 
       FIGS.  11 - 16    illustrate alternative embodiments of bag forming apparatuses  110 ,  210 ,  310 ,  410 ,  510 , and  610 . The bag forming apparatuses  110 - 610  are substantially similar to the above-referenced bag forming apparatus  10 , and consequently use the same reference numerals but respectively indexed by  100 ,  200 ,  300 ,  400 ,  500 , and  600  to denote structures corresponding to similar structures in the bag forming apparatuses  10 - 610 . In addition, the foregoing description of the bag forming apparatus  10  is equally applicable to the bag forming apparatuses  110 - 610 , except as noted below. Moreover, aspects of the bag forming apparatuses  10 - 610  may be substituted for one another or used in conjunction with one another where applicable. 
       FIGS.  11 A and  11 B  show another exemplary embodiment of a bag forming apparatus  110 .  FIG.  11 A  shows the apparatus  110  in an exemplary collapsed state, and  FIG.  11 B  shows the apparatus  110  in an exemplary expanded state. As shown, the apparatus  110  includes a base  112 , opposing sidewalls  114 ,  116  that extend upright relative to the base  112 , and a top  118  that is operably coupled to an upper portion  130 ,  134  of each of the sidewalls. The top  118  may be operably coupled to the sidewalls  114 ,  116  with respective upper hinges  140 , and the base  112  may be operably coupled to sidewalls  114 ,  116  with respective lower hinges  126 . The top  118  includes respective first and second top portions  128 ,  132  that are pivotable relative to each other about an intermediate pivot axis  145 . The intermediate pivot axis  145  may be provided by an intermediate hinge that operably couples the first and second top portions  128 ,  132  together. In the collapsed state ( FIG.  11 A ), the upper portions  130 ,  134  of the respective sidewalls  114 ,  116  are closer together compared to the expanded state, and the top  118  (e.g., top portions  128 ,  132 ) extends upright relative to the base  112  to form a tip  148  that is configured for insertion into an opening of a bag. In the expanded state ( FIG.  11 B ), the upper portions  130 ,  134  of the respective sidewalls  114 ,  116  are spaced further apart compared to the collapsed state, and the top  118  extends horizontally relative to the base  112  to form a platform  160  that is configured for forming the flat bottom of the bag. In the illustrated embodiment, the first and second sidewalls  114 ,  116  extend upright perpendicularly to the base  112  in the collapsed state ( FIG.  11 A ). In the expanded state ( FIG.  11 B ), the first and second sidewalls  114 ,  116  are inclined upwardly and outwardly away from each other, which may facilitate forming the bottom of the bag. 
       FIGS.  12 A and  12 B  show another exemplary embodiment of a bag forming apparatus  210 .  FIG.  12 A  shows the apparatus  210  in an exemplary collapsed state, and  FIG.  12 B  shows the apparatus  210  in an exemplary expanded state. As shown, the apparatus  210  includes a base  212 , opposing sidewalls  214 ,  216  that extend upright relative to the base  212 , and a top  218  that is operably coupled to an upper portion  230 ,  234  of each of the sidewalls. The top  218  may be operably coupled to the sidewalls  214 ,  216  with respective upper hinges  240 , and the base  212  may be operably coupled to sidewalls  214 ,  216  with respective lower hinges  226 . The top  218  includes respective first and second top portions  228 ,  232  that are pivotable relative to each other about an intermediate pivot axis  245 . The intermediate pivot axis  245  may be provided by an intermediate hinge that operably couples the first and second top portions  228 ,  232  together. In the collapsed state ( FIG.  12 A ), the upper portions  230 ,  234  of the respective sidewalls  214 ,  216  are closer together compared to the expanded state, and the top  218  (e.g., top portions  228 ,  232 ) extends upright relative to the base  212  to form a tip  248  that is configured for insertion into an opening of a bag. In the expanded state ( FIG.  12 B ), the upper portions  230 ,  234  of the respective sidewalls  214 ,  216  are spaced further apart compared to the collapsed state, and the top  218  extends horizontally relative to the base  212  to form a platform  260  that is configured for forming the flat bottom of the bag. In the illustrated embodiment, the first and second sidewalls  214 ,  216  are inclined upwardly and inwardly toward each other in the collapsed state ( FIG.  12 A ). In the expanded state ( FIG.  12 B ), the first and second sidewalls  214 ,  216  extend upright perpendicularly to the base  112 . 
       FIGS.  13 A and  13 B  show another exemplary embodiment of a bag forming apparatus  310 .  FIG.  13 A  shows the apparatus  310  in an exemplary collapsed state, and  FIG.  13 B  shows the apparatus  310  in an exemplary expanded state. As shown, the apparatus  310  includes a base  312 , opposing sidewalls  314 ,  316  that extend upright relative to the base  312 , and a top  318  that is operably coupled to an upper portion  330 ,  334  of each of the sidewalls. The top  318  may be operably coupled to the sidewalls  314 ,  316  with respective upper hinges  340 , and the base  312  may be operably coupled to sidewalls  314 ,  316  with respective lower hinges  326 . The top  318  includes respective first and second top portions  328 ,  332  that are pivotable relative to each other about an intermediate pivot axis  345 . The intermediate pivot axis  345  may be provided by an intermediate hinge that operably couples the first and second top portions  328 ,  332  together. In the collapsed state ( FIG.  13 A ), the upper portions  330 ,  334  of the respective sidewalls  314 ,  316  are closer together compared to the expanded state, and the top  318  (e.g., top portions  328 ,  332 ) extends upright relative to the base  312  to form a tip  348  that is configured for insertion into an opening of a bag. In the expanded state ( FIG.  13 B ), the upper portions  330 ,  334  of the respective sidewalls  314 ,  316  are spaced further apart compared to the collapsed state, and the top  318  extends horizontally relative to the base  312  to form a platform  360  that is configured for forming the flat bottom of the bag. In the illustrated embodiment, base  312  includes multiple discrete base parts  312   a ,  312   b , with each sidewall  314 ,  316  being operably coupled to a respective base part  312   a ,  312   b.    
       FIGS.  14 A and  14 B  show another exemplary embodiment of a bag forming apparatus  410 .  FIG.  14 A  shows the apparatus  410  in an exemplary collapsed state, and  FIG.  14 B  shows the apparatus  410  in an exemplary expanded state. As shown, the apparatus  410  includes a base  412 , opposing sidewalls  414 ,  416  that extend upright relative to the base  412 , and a top  418  that is operably coupled to an upper portion  430 ,  434  of each of the sidewalls. The top  418  may be operably coupled to the sidewalls  414 ,  416  with respective upper hinges  440 , and the base  412  may be operably coupled to sidewalls  414 ,  416  with respective lower hinges  426 . The top  418  includes respective first and second top portions  428 ,  432  that are pivotable relative to each other about an intermediate pivot axis  445 . The intermediate pivot axis  445  may be provided by an intermediate hinge that operably couples the first and second top portions  428 ,  432  together. In the collapsed state ( FIG.  14 A ), the upper portions  430 ,  434  of the respective sidewalls  414 ,  416  are closer together compared to the expanded state, and the top  418  (e.g., top portions  428 ,  432 ) extends upright relative to the base  412  to form a tip  448  that is configured for insertion into an opening of a bag. In the expanded state ( FIG.  14 B ), the upper portions  430 ,  434  of the respective sidewalls  414 ,  416  are spaced further apart compared to the collapsed state, and the top  418  extends horizontally relative to the base  412  to form a platform  460  that is configured for forming the flat bottom of the bag. In the illustrated embodiment, base  412  includes multiple discrete base parts  412   a ,  412   b , with each base part having an upward extension portion  380   a ,  380   b  to which each sidewall  414 ,  416  is operably coupled. 
       FIGS.  15 A and  15 B  show another exemplary embodiment of a bag forming apparatus  510 .  FIG.  15 A  shows the apparatus  510  in an exemplary collapsed state, and  FIG.  15 B  shows the apparatus  510  in an exemplary expanded state. As shown, the apparatus  510  includes a base  512 , opposing sidewalls  514 ,  516  that extend upright relative to the base  512 , and a top  518  that is operably coupled to an upper portion  530 ,  534  of each of the sidewalls. The top  518  may be operably coupled to the sidewalls  514 ,  516  with respective upper hinges  540 , and the base  512  may be operably coupled to sidewalls  514 ,  516  with respective lower hinges  526 . The top  518  includes respective first and second top portions  528 ,  532  that are pivotable relative to each other about an intermediate pivot axis  545 . The intermediate pivot axis  545  may be provided by an intermediate hinge that operably couples the first and second top portions  528 ,  532  together. In the collapsed state ( FIG.  15 A ), the upper portions  530 ,  534  of the respective sidewalls  114 ,  116  are closer together compared to the expanded state, and the top  518  (e.g., top portions  528 ,  532 ) extends upright relative to the base  512  to form a tip  548  that is configured for insertion into an opening of a bag. In the expanded state ( FIG.  15 B ), the upper portions  530 ,  534  of the respective sidewalls  514 ,  516  are spaced further apart compared to the collapsed state, and the top  518  extends horizontally relative to the base  512  to form a platform  560  that is configured for forming the flat bottom of the bag. In the illustrated embodiment, the first and second sidewalls  514 ,  516  are located close together in the collapsed state ( FIG.  15 A ) to form a slender profile for insertion into the bag. In exemplary embodiments, the first and second sidewalls  514 ,  516  may engage each other in the collapsed state, such as along a majority or an entirety of the length of the sidewalls  514 ,  516 . As shown in the collapsed state, the first and second sidewalls  514 ,  516  extend upright perpendicularly to the base  512 . In the expanded state ( FIG.  11 B ), the first and second sidewalls  114 ,  116  are inclined upwardly and outwardly away from each other with their respective lower portions being in close proximity or touching. 
       FIGS.  16 A and  16 B  show another exemplary embodiment of a bag forming apparatus  610 .  FIG.  16 A  shows the apparatus  610  in an exemplary collapsed state, and  FIG.  16 B  shows the apparatus  610  in an exemplary expanded state. As shown, the apparatus  610  includes a base  612 , opposing sidewalls  614 ,  616  that extend upright relative to the base  612 , and a top  618  that is operably coupled to an upper portion  630 ,  634  of each of the sidewalls. The top  118  may be operably coupled to the sidewalls  614 ,  616  with respective upper hinges  640 . The top  618  includes respective first and second top portions  628 ,  632  that are pivotable relative to each other about an intermediate pivot axis  645 . The intermediate pivot axis  645  may be provided by an intermediate hinge that operably couples the first and second top portions  628 ,  632  together. In the collapsed state ( FIG.  16 A ), the upper portions  630 ,  634  of the respective sidewalls  614 ,  616  are closer together compared to the expanded state, and the top  618  (e.g., top portions  628 ,  632 ) extends upright relative to the base  612  to form a tip  648  that is configured for insertion into an opening of a bag. In the expanded state ( FIG.  16 B ), the upper portions  630 ,  634  of the respective sidewalls  614 ,  616  are spaced further apart compared to the collapsed state, and the top  618  extends horizontally relative to the base  612  to form a platform  660  that is configured for forming the flat bottom of the bag. In the illustrated embodiment, the first and second sidewalls  614 ,  616  are non-pivotably fixed to the base  612 . As shown in the expanded state ( FIG.  16 B ), the first and second sidewalls  614 ,  616  are configured to flex to accommodate the movement of the top  618  and sidewalls  614 ,  616  when forming the platform  660 . 
     Exemplary bag forming apparatuses  10 - 610  and an exemplary method for forming the bottom of a bag have been described herein. The exemplary bag forming apparatus ( 10 - 610 ) includes a base ( 12 - 612 ), opposing sidewalls ( 14 - 614 ,  16 - 616 ) that extend upright relative to the base, and a top ( 18 - 618 ) that is operably coupled to an upper portion ( 30 - 630 ,  34 - 634 ) of each of the sidewalls. The top has an intermediate pivot axis ( 45 - 645 ) between the sidewalls that enables the top to pivot about the pivot axis between a collapsed state and an expanded state. In the collapsed state, the upper portions of the respective sidewalls are closer together and the top extends upright relative to the base to form a tip ( 48 - 648 ) that is configured for insertion into an opening of the bag. In the expanded state, the upper portions of the respective sidewalls are spaced further apart, and the top extends horizontally relative to the base to form a platform ( 60 - 660 ) that is configured for forming the flat bottom of the bag. 
     Such an exemplary bag forming apparatus ( 10 - 610 ) may provide a simplified construction that enables a user to manually form the flat bottom of a bag, such as at the point of use. More particularly. the bag forming apparatus may be designed as a relatively small fixture, with which the user forms the flat bottom of the bag just prior to its use. The simplified construction of the bag forming apparatus may make it inexpensive to manufacture and reproduce, lighter and more compact than existing bag-making machinery, and thus may be deployed at or moved between many point of use locations. 
     According to an aspect of the present disclosure, a bag forming apparatus for forming a bottom of a bag includes: a base; opposing sidewalls, each sidewall being operably coupled at a lower portion thereof for enabling movement of the sidewalls relative to each other; a top operably coupled to an upper portion of each of the sidewalls, the top having an intermediate pivot axis between the sidewalls, wherein the top is pivotable about the pivot axis to move between a collapsed state and an expanded state; where in the collapsed state, the upper portions of the respective sidewalls are closer together and the top extends upright relative to the base to form a tip that is configured for being received in an opening of the bag; and where in the expanded state, the upper portions of the respective sidewalls are spaced further apart and the top extends horizontally relative to the base to form a platform that is configured for forming the flat bottom of the bag. 
     According to another aspect of the present disclosure, a bag forming apparatus for forming a paper bag having a flat bottom includes: a base; first and second sidewalls that extend upright relative to the base, each of the first and second sidewalls being hinged for pivotable movement relative to the base and relative to each other; and a top having a first top portion that is hinged to the first sidewall, and a second top portion that is hinged to the second sidewall, the first and second top portions being hinged together at an intermediate pivot location between the first and second sidewalls for enabling the first and second top portions to pivot relative to each other between a collapsed state and expanded; where in the collapsed state, the first and second top portions are inclined relative to the base to form a tip that is configured to facilitate the top and sidewalls to be received in an opening of the bag; and where in the expanded state, the first and second top portions are horizontal relative to the base to form a platform that is configured to facilitate formation of the flat bottom of the bag. 
     Embodiments may include the foregoing aspect(s) in combination with one or more of the following additional features, separately or in any combination. 
     In some embodiments, where in the collapsed state, the tip is formed at the intermediate pivot location of the top that is at an elevation above the first and second sidewalls. 
     In some embodiments, where in the expanded state, the first and second top portions are coplanar with each other to form the platform with a flat upper surface. 
     In some embodiments, the first and second sidewalls are each hinged at a lower portion thereof. 
     In some embodiments, the first and second top portions are respectively hinged to the first and second sidewalls at an upper portion thereof. 
     In some embodiments, where in the collapsed state, the first and second top portions are inclined upwardly and inwardly toward each other to form the tip. 
     In some embodiments, where in the collapsed state, the first and second sidewalls are inclined upwardly and inwardly toward each other. 
     In some embodiments, where in in the expanded state, the first and second sidewalls are perpendicular to the base and parallel to each other. 
     In some embodiments, where in the expanded state, the first and second sidewalls are inclined upwardly and outwardly away from each other. 
     In some embodiments, the first and second sidewalls oppose each other and are hinged to opposite sides of the base. 
     In some embodiments, the base is a single base. 
     In some embodiments, the base includes multiple discrete bases. 
     In some embodiments, the apparatus includes respective lower hinges that operably couple the first and second sidewalls to the base, and includes respective upper hinges that operably couple the first and second sidewalls to the respective first and second top portions, and includes at least one intermediate hinge that operably couples the first and second top portions at the intermediate location. 
     In some embodiments, one or more of the respective upper hinges, respective lower hinges, and at least one intermediate hinge is a living hinge, a barrel hinge, or any other suitable hinge. 
     In some embodiments, the apparatus further includes a biasing member operably coupled to the first and second sidewalls, wherein the biasing member biases the apparatus toward the collapsed state. 
     In some embodiments, the biasing member is a coil spring interposed between the first and second sidewalls. 
     In some embodiments, the first and second top portions have respective mating faces at the intermediate pivot location, the respective mating faces being configured to engage each other when the apparatus is in the expanded state, thereby restricting further pivotable movement of the first and second top portions. 
     In some embodiments, the first and second sidewalls are spaced apart in a width direction of the apparatus. 
     In some embodiments, one or more upright supports are disposed between the first and second sidewalls, the upright supports being configured to engage and support the sidewalls when the apparatus is in the collapsed state. 
     In some embodiments, each of the one or more upright supports has opposite tapered surfaces that respectively face the first and second sidewalls, the opposite tapered surfaces being configured to engage and support the sidewalls when the apparatus is in the collapsed state. 
     In some embodiments, the one or more upright supports includes two upright supports that are spaced apart in a depth direction of the apparatus. 
     In some embodiments, the first and second top portions form a rectangular shape for forming the bottom of the bag in a rectangular shape. 
     In some embodiments, the apparatus is in combination with the paper bag. 
     In some embodiments, the bag includes a slit sheet material. 
     According to another aspect of the present disclosure, a method of forming a flat-bottomed bag includes the following steps: (i) placing a bag preform over a top and opposing sidewalls of a bag forming apparatus that is in a collapsed state, where in the collapsed state the top of the apparatus extends upright relative to a base of the apparatus to form a tip that is received in an opening of the bag preform during the placing step; (ii) engaging the top of the apparatus, where the engaging step causes the top to pivot about an intermediate portion of the top to an expanded state, where in the expanded state the top extends horizontally relative to the base of the apparatus to form a platform; and (iii) forming a flat bottom of the bag preform on the platform to thereby form the flat-bottomed bag. 
     Embodiments may include the foregoing aspect in combination with one or more of the following additional features, separately or in any combination. 
     In some embodiments, the method further includes the step of: providing the bag forming apparatus for forming the flat-bottomed bag; where the opposing sidewalls are respectively hinged at lower portions thereof; where the top includes a first portion hinged to an upper portion of one of the opposing sidewalls, and a second portion hinged to an upper portion of an other one of the opposing sidewalls; and where the first and second top portions are hinged together at the intermediate portion of the top. 
     In some embodiments, during the placing step when the bag forming apparatus is in the collapsed state, the upper portions of the respective sidewalls are closer together and the top extends upright relative to a base of the apparatus to form the tip at an elevation above the opposing sidewalls. 
     In some embodiments, during the engaging step, the bag forming apparatus is transformed to the expanded state, such that the upper portions of the respective sidewalls are moved to locations that are spaced further apart, and the top is moved to extend horizontally relative to the base to form the platform. 
     In some embodiments, the method further includes the step of: providing the bag preform; where the bag preform is bounded on at least one side to form a tube, the tube having first and second openings on opposite sides thereof, where the placing step includes inserting the tip of the apparatus into the first opening, and where the forming step includes forming the bottom of the bag preform on the side of the tube with the second opening. 
     In some embodiments, the method further includes the step of: providing the bag preform; where the bag preform is bounded on at least three sides to form a pouch, the pouch having an opening that opens into a pocket; where the placing step includes inserting the tip of the apparatus into the opening; where the engaging step includes moving the bag preform downwardly to engage an inside bottom of the pouch with the top of the apparatus; and where the forming step includes forming the bottom of the bag preform on a bounded side of the pouch that is opposite the opening. 
     In some embodiments, the step of forming the flat bottom of the bag preform includes folding the bag preform. 
     In some embodiments, during the step of forming of the flat bottom of the bag preform, gussets are formed that are folded over and attached to the bottom. 
     In some embodiments, the forming step includes forming the bottom of the bag preform as a rectangular bottom. 
     In some embodiments, the method further includes the step of providing the bag preform, where the bag preform is a multi-layered material. 
     In some embodiments, the multi-layered material includes a cushioning material or an insulating material. 
     In some embodiments, the cushioning material or insulating material includes slit sheet material. 
     In some embodiments, the cushioning material is bounded on at least one of its sides with a layer of continuous sheet. 
     The terms such as “top,” “bottom,” “upper,” “lower,” “left,” “right,” “front,” “rear,” “forward,” “rearward,” and the like as used herein may refer to an arbitrary frame of reference, rather than to the ordinary gravitational frame of reference. 
     As used herein, an “operable coupling,” “operable connection,” or a coupling/connection by which entities are operably coupled/connected, is one in which the entities are connected in such a way that the entities may perform as intended. An operable connection may be a direct connection or an indirect connection in which an intermediate entity or entities cooperate or otherwise are part of the connection or are in between the operably connected entities. An operable connection or coupling may include the entities being integral and unitary with each other. 
     The phrase “and/or” should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified unless clearly indicated to the contrary. Thus, as a non-limiting example, a reference to “A and/or B,” when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A without B (optionally including elements other than B); in another embodiment, to B without A (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc. 
     Although the invention has been shown and described with respect to a certain embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.