Abstract:
A blow molded container has a neck portion defining a mouth. The neck portion leads into a shoulder portion and a bottom portion forms a container base. A sidewall portion connects the shoulder portion and the bottom portion and employs a first pair of opposing convex vacuum panels and a second pair of opposing convex vacuum panels. The first pair of opposing convex vacuum panels is larger in surface area than the second pair of opposing convex vacuum panels. A vertical column at each corner of the container joins the first pair of opposing vacuum panels to the second pair of opposing vacuum panels. A structural convex arch resides above and below each convex vacuum panel. Each of the vertical columns are molded into the structural convex arches. Vacuum initiator grooves may be molded into the first and second pair of opposing vacuum panels to control vacuum panel movement.

Description:
FIELD 
       [0001]    The present disclosure relates to a container that employs vertical columns and vacuum side panels to control container deformation during reductions in product volume that occur during cooling of a hot-filled product. 
       BACKGROUND 
       [0002]    The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. Containers made of plastic, such as polyethylene terephthalate (“PET”), have become commonplace for the packaging of liquid products, such as fruit juices and sports drinks, which must be filled into a container while the liquid is hot to provide for adequate and proper sterilization of the product. Because these plastic containers are normally filled with a hot liquid, the product that occupies the container is commonly referred to as a “hot-fill product,” and the container is commonly referred to as a “hot-fill container.” During filling of the container, the product is typically dispensed into the container at a temperature of at least 180° F. Immediately after filling, the container is sealed or capped, such as with a threaded cap, and as the product cools to room temperature, a negative internal pressure or vacuum forms within the sealed container. Although PET containers that are hot-filled have been in use for quite some time, such containers are not without their share of limitations. 
         [0003]    One limitation of PET containers that receive a hot-filled product is that during cooling of the liquid product, the containers may undergo an amount of physical distortion. More specifically, a vacuum or negative internal pressure caused by a cooling and contracting internal liquid may cause the container body or sidewalls to deform in unacceptable ways to account for the pressure differential between the space inside of the container and the space outside, or atmosphere surrounding, the container. Containers with deformations are aesthetically unpleasing and may lack mechanical properties to ensure sustained container strength or sustained structural integrity while under a negative pressure. 
         [0004]    Another limitation of PET containers that receive a hot-filled product is that they are not easily held by a hand of a handler, such as a consumer who is drinking the product directly from the container or pouring the product from the container into a smaller container, such as a drinking glass. For instance, intended container gripping areas typically located on the body of containers are not designed to conform to a user&#39;s hand or accept specific parts of a user&#39;s hand to maximize holding capacity while also accounting for the above-mentioned pressure differential associated with hot-filled containers. 
         [0005]    Another limitation of plastic containers, such as hot-fill containers, is that such containers may be susceptible to buckling during storage or transit. Typically, to facilitate storage and shipping of PET containers, they are packed in a case arrangement and then the cases are stacked case upon case, such as on pallets that are then lifted and moved with fork-lifts. While stacked one upon another, each container is capable of buckling and subject to compression upon itself due to the weight of direct vertical loading. Such loading may result in container deformation or container rupture, both of which are potentially permanent, which may then render the container and internal product as unsellable or unusable. 
         [0006]    Yet another limitation with hot-filled containers lies in preserving the body strength of the container during the cooling process. One way to achieve container body strength is to place a multitude of vertical or horizontal ribs in the container to increase the moment of inertia in the body wall in select places. However, such multitude of ribs increases the amount of plastic material that must be used and thus contributes to the overall weight and size of the container. 
       SUMMARY 
       [0007]    The present invention provides a hot-fillable, blow-molded plastic container suitable for receiving a liquid product that is initially delivered into the container at an elevated temperature. The container is subsequently sealed such that liquid product cooling results in a reduced product volume and a reduced pressure within the container. The container is lightweight compared to containers of similar size yet controllably accommodates the vacuum pressure created in the container. Moreover, the container provides excellent structural integrity and resistance to top loadings from filler valves and weight placed on top of the container. The container advantageously accommodates more than one size hand for secure gripping and handling of the container. A vertical column at each of the four corners of the container provides hoop strength, a physical gripping area suited to the human hand, and vertical strength so that the container may resist buckling under top loading. 
         [0008]    Possessing a central vertical and a central horizontal axis, as well as a body or sidewall central horizontal axis, the container structure further employs a neck portion defining a mouth, a shoulder portion that is formed with and molded into the neck portion and that extends downward from the neck portion, a bottom portion forming a base, and a body or sidewall that extends between and joins the shoulder portion and the bottom portion. The sidewall further defines four vertical columns, one at each corner of the container to facilitate gripping, provide strength to the sidewall, and concentrate and direct sidewall movement. When filled with a hot liquid that is then cooled, the four columns provide overall container strength to permit the walls between the columns to contract inward to an extent because the container interior experiences and sustains an interior vacuum. Moreover, the body or sidewall defines a pair of opposing vacuum panels that are oriented between the columns. The base and shoulder areas employ arches above each of the vacuum panels to provide strength to the shoulder and base areas. The arches protrude outwardly to approximately the same extent as the columns so that the vacuum panels are recessed to facilitate gripping. Vacuum initiators, also called hinges or grooves, are longitudinally resident in the vacuum panels and are formed as part of each of the pair of opposing vacuum panels. 
         [0009]    Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
     
    
     
       DRAWINGS 
         [0010]    The drawings described herein are to scale and are for illustration purposes only. The drawings are not intended to limit the scope of the present disclosure in any way. 
           [0011]      FIG. 1  is an overall perspective view of a container depicting sidewalls with vacuum panels; 
           [0012]      FIG. 2  is a side view of a broad side of the container depicting a sidewall with a vacuum panel and columns; 
           [0013]      FIG. 3  is a side view of a narrow side of the container depicting a sidewall with a vacuum panel and columns; 
           [0014]      FIG. 4  is a top view of the container depicting a generally rectangular container shape; 
           [0015]      FIG. 5  is a bottom view of the container depicting columns at each of the corners of the container; 
           [0016]      FIG. 6  is longitudinal cross-sectional view of the container depicting the vacuum panels of the container; 
           [0017]      FIG. 7  is a perspective cross-sectional view of the container depicting the vacuum panels and vacuum initiators in the vacuum panels; and 
           [0018]      FIG. 8  is a cross-sectional line view of the container depicting movement of the vacuum panels before and after a vacuum is present within the container. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. 
         [0020]    Referring now to  FIGS. 1-8 , and first to  FIG. 1 , a hot-fill, blow molded plastic container  10  is depicted that exemplifies principles of the present invention. The container  10  is designed to be filled with a product, typically a liquid such as a fruit juice or sports drink, while the product is in a hot state, such as at or above 180 degrees Fahrenheit. After filling, the container  10  is sealed, such as with a cap  12 , and then cooled. During cooling, the volume of the product in the container  10  decreases which in turn results in a decreased pressure, or vacuum, within the container  10 . While designed for use in hot-fill applications, it is noted that the container  10  is also acceptable for use in non-hot-fill applications. 
         [0021]    Since the container  10  is designed for “hot-fill” applications, the container  10  is manufactured out of a plastic material, such as polyethylene terephthalate (“PET”), and is heat set enabling such that the container  10  is able to withstand the entire hot-fill procedure without undergoing uncontrolled or unconstrained distortions. Such distortions may result from either or both of the temperature and pressure during the initial hot-filling operation or the subsequent partial evacuation of the container&#39;s interior as a result of cooling of the product. During the hot-fill process, the product may be, for example, heated to a temperature of about 180 degrees Fahrenheit or above and dispensed into the already formed container  10  at these elevated temperatures. 
         [0022]    As depicted best in  FIGS. 1-3 , the container  10  generally includes a neck  14 , which defines a mouth  16 , a shoulder portion  18  and a bottom portion  20  forming a base  21  ( FIG. 5 ). As depicted, the shoulder portion  18  and the bottom portion  20  may be substantially rectangular in cross-section. The cap  12  engages threads  22  on the neck  14  to close and seal the mouth  16 . 
         [0023]    Extending between the shoulder portion  18  and the bottom portion  20  is a sidewall or body  24  of the container  10 . As best depicted in  FIGS. 1 ,  4 - 5 , and  7 - 8 , the sidewall  24  may be approximately, substantially rectangular in cross-section to facilitate gripping by various sizes of human hands. More specifically, near the transition between the shoulder portion  18  and the sidewall  24 , the cross-sectional shape may be relatively rectangular; however, as the shoulder portion  18  approaches the neck  14 , the rectangular cross-sectional area decreases and transforms into a circular cross-section, which defines the neck  14 . Within and throughout the sidewall  24 , between the shoulder portion  18  and the bottom portion  20 , the cross-sectional shape is relatively consistent, as depicted in  FIGS. 1-3 , for example. While the container  10  depicted is generally rectangular, other polygonal shapes, such as square, hexigon, multi-sided, and circular, are similarly contemplated. 
         [0024]    Continuing, between the shoulder portion  18  and the bottom portion  20 , the sidewall  24  employs vacuum panels  34 ,  36 ,  38 ,  40  between columns  26 ,  28 ,  30 ,  32 . More specifically, vacuum panel  34  exists between column  26  and column  32 , vacuum panel  36  exists between column  32  and column  30 , vacuum panel  38  exists between column  30  and column  28 , and vacuum panel  40  exists between column  28  and column  26 . As depicted, for example in  FIG. 8 , vacuum panels  34 ,  36 ,  38 ,  40  are recessed or set-back toward a central vertical axis  42  of the container  10  as compared to the positioning of columns  26 ,  28 ,  30 ,  32 , which jut-out or protrude outwardly and away from the central vertical axis  42  and vacuum panels  34 ,  36 ,  38 ,  40 . Vacuum panels  34 ,  36 ,  38 ,  40  move in response to the creation of an internal vacuum pressure created during the cooling of a hot-fill product within the capped and sealed container  10 . Vacuum panels  34 ,  36 ,  38 ,  40  may be convex to provide strength to the sidewall  24 . With continued reference to  FIG. 8 , vacuum panel  34  and vacuum panel  38  depict movement in response to hot-fill product cooling. For instance, with respect to vacuum panel  38 , the panel can be seen to move from molded position  44  to contraction position  46 . In another example, the movement of the container  10  is relatively large compared to vacuum panel  38 . For instance, vacuum panel  40  as molded may assume the molded position  48 , while after hot-filling and capping the container  10 , may assume the contraction position  50 . 
         [0025]    With continued reference to the to-scale depiction of  FIG. 8 , the vacuum panel  40  and its opposing counterpart, vacuum panel  36 , undergo more movement than vacuum panels  34 ,  38 , which also oppose each other. The reason for the larger movement of vacuum panels  36 ,  40  is due to the distance between the columns that support vacuum panels  36 ,  40 . More specifically, column  26  and column  28 , which support vacuum panel  40 , and column  30  and column  32 , which support vacuum panel  36 , are located farther apart from one another than column  28  and column  30 , which support vacuum panel  38 , and column  26  and column  32 , which support vacuum panel  34 . The ability of a vacuum panel to resist bending and flexure due to the internal vacuum pressure of the cooling hot-fill liquid within the container  10  is related to the distance that vacuum panels  34 ,  36 ,  38 ,  40  span between columns  26 ,  28 ,  30 ,  32 , with all other parameters being equal, such as panel thickness and panel geometry. Columns  26 ,  28 ,  30 ,  32  provide vertical strength and resistance to longitudinal flexure or bending as well as hoop strength to resist internal pressure. Columns  26 ,  28 ,  30 ,  32  exist at what would otherwise be the extended intersection of vacuum panels  34 ,  36 ,  38 ,  40  or at the corners of the container  10 . 
         [0026]    The container  10  is equipped with two larger vacuum panels  36 ,  40  and two smaller vacuum panels  34 ,  38 , supported by columns on either side of the vacuum panels, as explained above. However, the container  10  possesses additional structural features to centralize or concentrate the deformation of the container  10  at vacuum panels  34 ,  36 ,  38 ,  40 .  FIG. 2  depicts the larger vacuum panel  36  positioned within the perimeter or confines of semi-circular or approximately semi-circular arches that afford vacuum panel  36  with additional strength and aid in concentrating vacuum panel  36  deformation. With respect to vacuum panel  36 , an upper arch  52  is a transitional structure between vacuum panel  36  and shoulder portion  18 .  FIG. 2  depicts how an exterior surface  56  of the upper arch  52  is slightly raised, or protrudes outward slightly more than an exterior surface  58  of columns  30 ,  32 . The juncture between the exterior surface  56  and the exterior surface  58  is blended or connected at an intermediary surface  61  that is angled, at an angle other than a right angle, relative to the central vertical axis  42 . Because the exterior surface  56  of the container  10  has a larger overall circumference than the overall container circumference around the columns, the resistance to vacuum pressure and thus deformation is greater. 
         [0027]    Regarding container deformation, and with continued reference to  FIG. 2 , because the columns  30 ,  32 , the upper arch  52  and the lower arch  54  surround and isolate the vacuum panel  36 , deformation is primarily limited to the vacuum panel  36 , which includes an upper arch panel  60  and a lower arch panel  62 . The deformation of the entire vacuum panel  36  generally follows an oblong or oval pattern with respect to degree of deformation. That is, deformation is greatest in the interior area bounded by an oval  64 . Deformation would then be somewhat less within the area bounded by oval  66 , and decrease in successive oval areas outward toward columns  30 ,  32  and arch panels  60 ,  62 . However, some deformation does occur in columns  30 ,  32  as depicted in the cross-sectional view through the sidewall  24 , including the vacuum panel  36 , of  FIG. 8 . The arch panels above the vacuum panels  34 ,  36 ,  38 ,  40 , for example arch panels  60 ,  68 , and the arch panels below the vacuum panels  34 ,  36 ,  38 ,  40 , for example arch panels  62 ,  70  may be convex to provide strength to the arch panels and control deformation of the arch panels. While the arch panels may act as a vacuum panel, they do not possess vacuum initiators and therefore, may not deflect as much as the vacuum panels  34 ,  36 ,  38 ,  40 . 
         [0028]    Because the container  10  depicted in  FIGS. 1-8  may be rectangular, the container  10  has two opposing vacuum panels  34 ,  38  that are smaller in surface area than opposing vacuum panels  36 ,  40 . As a representative example of one of the smaller vacuum panels,  FIG. 3  depicts the vacuum panel  34  located between columns  26 ,  32 . Similar to vacuum panel  36 , the vacuum panel  34  has an area of deformation bounded by ovals  64 ,  66  within which deformation takes place when the internal volume of the container  10  is placed under a vacuum. More specifically, oval  64  will undergo a larger deformation than oval  66  because oval  64  is farther from either of columns  26 ,  32 . Similar to the upper and lower arch panels  60 ,  62  above and below vacuum panel  36  of  FIG. 2 , above vacuum panel  34  of  FIG. 3  is an upper arched panel  68  and a lower arched panel  70 . The arched panels  68 ,  70  may undergo deformation depending upon the degree of vacuum pressure within the container  10  upon hot-product cooling. Regardless of the amount of deformation that the vacuum panel  34  and the arched panels  68 ,  70  may undergo, there is also an upper arch  72  and a lower arch  74  to prevent deformation from being experienced outside of the vacuum panel  34  and the arched panels  68 ,  70 . 
         [0029]    Another important feature of containers is their ability to be easily handled with a secure grip by a human hand. The container  10  of the present teachings is designed to be easily and securely gripped by a variety of hand sizes even if the container  10  contains 64 fluid ounces (1893 ml) or more of a liquid product. With reference to  FIGS. 1-3 , the positioning of columns  26 ,  28 ,  30 ,  32  provides a semi-circular structure (approximately 180 degrees) with the same radius with which to grip the container  10 . With vacuum panels  34 ,  36 ,  38 ,  40  being recessed or located more closely to the central vertical axis  42  of the container  10  than the central axis of the columns, such as central column axis  76  of column  28  and central column axis  78  of column  30  (see  FIG. 8 ), columns  26 ,  28 ,  30 ,  32  become easy and more secure to grip. Stated slightly differently, with columns  26 ,  28 ,  30 ,  32  protruding radially farther from the central vertical axis  42  of the container  10  than vacuum panels  34 ,  36 ,  38 ,  40 , they provide a secure grip to a human hand.  FIG. 8  depicts a secure grip by an index finger  80  around the column  28  and a thumb  82  around the column  30 . In one example, the grip is deemed to be secure because a gripping force  84  of the index finger  80  and a gripping force  86  of the thumb  82  is coincident with an axis  88  that defines the straight line distance between the central column axis  76  and the central column axis  78 . However, the structure of  FIG. 8  permits the gripping force  84  to be applied to the column  28  and the gripping force  86  to be applied to the column  30  such that the gripping forces  84 ,  86  are beyond or past the axis  88  that defines the straight line distance between the central column axes  76 ,  78  to place the gripping force  84  between the central column axis  76  and the central vertical axis  42 , and the gripping force  86  between the central column axis  78  and the central vertical axis  42 . This combination of the placement of columns  28 ,  30  and the application of gripping forces  84 ,  86  relative to the central vertical axis  42 , results in a very secure grip. If the gripping force is not applied past the axis  88 , or rather, between the axis  88  and the central vertical axis  42 , as viewed in  FIG. 8 , the grip will not be secure. Another reason that the grip immediately described is so secure is that if the force of gravity has a component in direction  96 , each of the finger gripping forces  84 ,  86  provide a component in the opposite direction, direction  98 , that permits the fingers to contact a respective column  28 ,  30 . Appendages  80 ,  82  each contact a respective column  28 ,  30  although  FIG. 8  does not particularly show such contact to preserve the integrity of the entire container  10  profile. Appendages  80 ,  82  wrap around columns  28 ,  30  during gripping. 
         [0030]    Another gripping configuration that is similar to the above configuration is one in which the index finger  80  may be gripped around column  26  and the thumb  82  may be gripped around column  28 . Such a grip may be better suited to a larger hand although the reasoning presented above in conjunction with  FIG. 8  would also apply to such a grip. 
         [0031]    Turning to  FIG. 4 , a top view of the container  10  depicts how the upper arches  52 ,  72 , blend into the shoulder portion  18  to create a smooth transition with no sharp or abrupt angles thereby creating a vessel whose internal vacuum draws evenly on the entire internal wall surface area. The upper arches  52 ,  72  are referred to as horizontal arches because they are largely horizontal when the container is standing with its bottom surface upon a flat support surface. Vacuum panels  34 ,  36 ,  38 ,  40  are recessed or located closer to the central vertical axis  42  than the juncture of the upper arches  52 ,  72  to the shoulder portion  18  or the juncture of columns  26 ,  28 ,  30 ,  32  to the shoulder portion  18 .  FIG. 6 , which is a longitudinal cross-sectional view of the container  10 , also depicts how the shoulder portion  18  blends into the upper arch  52  and the upper arch panel  60 , and how the lower arch panel  62  blends into the lower arch  54  and the bottom portion  20 . 
         [0032]    Although columns  26 ,  28 ,  30 ,  32  provide structural rigidity to the container  10  by resisting deformation upon creation of a vacuum pressure within the container upon hot-product cooling, columns  26 ,  28 ,  30 ,  32  also provide longitudinal strength to the container  10  during top loading of the container  10 , which occurs when a load or force is applied to the container  10  coincident with or parallel to its central vertical axis  42 . More specifically, secondary packaging and shipping may cause added longitudinal forces and stress on the container  10 . Containers may be packed in cardboard boxes and/or wrapped in plastic, such as shrink wrap, and stacked onto a pallet, which causes the lower layers of containers to undergo increased force and stress. The ability of the container  10  to support a vertical load is improved with columns  26 ,  28 ,  30 ,  32  positioned at each of the four corners of the container  10 . Thus when cases, such as a case of six, twelve or twenty-four of the container  10  are hot-filled and capped, they may better support the forces and stresses caused by stacking arrangements, such as associated with stacking on a pallet. 
         [0033]    Turning now to  FIG. 5 , which depicts a bottom view of the container  10 , one can see how columns  26 ,  28 ,  30 ,  32  are positioned at the corners of the container  10 .  FIG. 5  also depicts how columns  26 ,  28 ,  30 ,  32  protrude farther from the central vertical axis  42  than the location of the vacuum panel  36 . All vacuum panels  34 ,  36 ,  38 ,  40  have a similar relationship with its respective columns  26 ,  28 ,  30 ,  32 , in that for a particular vacuum panel  34 ,  36 ,  38 ,  40 , the columns immediately beside such vacuum panel will protrude farther from the central vertical axis  42  than the vacuum panel. 
         [0034]      FIGS. 2 ,  7  and  8  depict another feature and advantage of the container  10 . The container  10  primarily has four vacuum panels  34 ,  36 ,  38 ,  40  whose movement is initiated and assisted with the use of vacuum initiators. An explanation will be provided using vacuum panel  36 , which employs vacuum initiators  100 ,  102  and  104 . More specifically, vacuum initiator  102  experiences the first and most movement of vacuum panel  36  initiators because it lies at the center, or equidistant between columns  30 ,  32 . As depicted with oval  64 , this is also the area that undergoes the most movement during the creation of a vacuum within the volume of the container  10 . The vacuum panel  36  is also equipped with vacuum initiators  100 ,  104  on either side of vacuum initiator  102 . Vacuum initiators  100 ,  104  also respond to an internal vacuum within the container  10 , but do not move toward the vacuum volume (toward the central vertical axis  42 ) as much as vacuum initiator  102  because vacuum initiator  100  is closer to the column  32  than vacuum initiator  102 , and vacuum initiator  104  is closer to the column  30  than vacuum initiator  102 . Thus, because columns  30 ,  32  are structural components and designed to not move, or move very little, relative to the vacuum panel  36  in response to an internal vacuum, the closer the vacuum panel material is to columns  30 ,  32 , the less movement there will be in the vacuum panel  36 . 
         [0035]    There is another advantage of the hot-fill container  10  regarding columns  26 ,  28 ,  30 ,  32 . Because columns  26 ,  28 ,  30 ,  32  are designed not to move or move very little, columns  26 ,  28 ,  30 ,  32  permit the container  10  to maintain its aesthetically pleasing appearance. As such, columns  26 ,  28 ,  30 ,  32  always act as a firm, non-deformable and secure gripping location for a human hand, as described above, regardless of whether an internal vacuum is present within the container  10 . 
         [0036]    The container  10  exhibits a further advantage. Hot-fill containers are known to be entirely cylindrical, which may be different from the teachings of the present container  10 . With elongate cylindrical containers, the entire sidewall may be susceptible to contraction upon cooling of a hot-fill liquid and then expansion to restore the container&#39;s original sidewall position. Such contraction and expansion causes loosening of any label on the sidewall, even if the label is glued to the sidewall. Wrinkling of the label may also occur. The container  10  solves this problem by lessening the contraction of certain panels and for other panels, spreading the contraction out over a large area thus making the panel of movement nearly flat. For instance,  FIG. 8  depicts the vacuum panels  34 ,  38  which move very little as evidenced by the molded position  44 , which indicates positioning before a vacuum is applied, and the contraction position  46 , which indicates positioning after a vacuum is applied. Such panel movement will not effect an attached label, which is an advantage of the structure. Similarly, vacuum panel  40  exhibits a before contraction vacuum panel molded position  48  and an after contraction vacuum panel contraction position  50 . The placement of a label on the vacuum panel  40  of the container  10  will, like the vacuum panel  38 , minimize or eliminate any label distortion during vacuum panel  40  contraction between vacuum panel molded position  48  and vacuum panel contraction position  50 . The vacuum panel  40  is equipped with vacuum initiators  100 ,  102  and  104 , and a land  108 , so that any paper or plastic product label that may be glued to the land  108  of the vacuum panel  40  may recede into the vacuum initiators  100 ,  102  and  104  during contraction of the vacuum panel  40  permitting the label portion glued to the land  108  to remain glued to the land  108 .