Abstract:
The present invention relates to a container end closure that generally comprises a pour opening and a secondary vent opening which improves venting during emptying of contents from the container. In particular, the present invention relates to an end closure for a container having scores defining a secondary vent opening which may optionally be opened. The secondary vent opening has a significantly larger area then vents of prior art designs and thereby improves pour rate and smoothness of pour. After the pour opening is opened using a pull tab interconnected to the end closure, a consumer may selectively open the secondary vent opening by pulling back on the tab.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 61/794,762 filed Mar. 15, 2013, which is incorporated herein in its entirety by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to a container end closure that generally comprises a pour opening and a secondary vent opening which improves venting during emptying of contents from the container. In particular, the present invention relates to an end closure for a container having scores defining a secondary vent opening which may optionally be opened. The secondary vent opening has a significantly larger area compared to vents of known designs and thereby improves pour rate and smoothness of pour. Additionally, the secondary vent opening does not require a separate tool for opening. 
       BACKGROUND 
       [0003]    Containers, and more specifically metallic beverage containers, are typically manufactured by interconnecting a beverage container end closure to the neck of a beverage container body. In some applications, an end closure may be interconnected on both a top side and a bottom side of a container body. More frequently, however, a beverage container end closure is interconnected on a top end of a beverage container body. Generally, the configuration of the container end closure may affect the level to which consumers, as well as bottlers, manufacturers, distributors, shippers, and retailers, are satisfied with the container. One factor believed to be of some importance to consumers is the pour characteristics of the container. In general, it is believed that consumers prefer to use containers capable of providing a relatively high pour rate. Additionally, it is believed consumers prefer containers that provide a smooth or substantially laminar pour, i.e., a pour which is not characterized by a series of surges or “glugging” which can cause splashing and/or can affect a beverage head, fizz or other carbonation or pressurization-related characteristics of the contents after pouring. 
         [0004]    Conventional beverage container end closures generally have a single pour opening defined by a score line. The pour opening is generally designed for pouring the container contents, with little or no consideration given to inward air flow needed for the volume exchange that facilitates smooth and consistent pouring. Therefore, conventional beverage container end closures generally suffer from low, inconsistent, and/or uneven flow rates as the contents in the container are poured due to the fact that these end closures have only one opening area of a predetermined size. 
         [0005]    There are several types of container end closures that have attempted to improve end closure pourability. One type is an end closure with a full aperture opening similar to a food can in which the entire end panel detaches from the can. Such fully detachable container end closures are not a good solution to the pourability problem because the fully detachable end frequently becomes litter when consumers do not properly dispose of the detached end. 
         [0006]    Other container end closures attempt to improve pourability with a secondary vent aperture which is separate from the primary drinking opening. The separate vent aperture can generally be opened with a separate tool or by pressing a secondary scored area into the container. Examples are provided in U.S. Patent Application Publication Nos. 2011/0108552, 2011/0266281, 2012/0048870, 2012/0199586, 2012/0260613, 2013/0118133, and WIPO Patent Application Publication No. 2008/023983 which are incorporated herein by reference in their entireties. The separate vent apertures of these designs are generally smaller than the primary opening limiting the flow of air into the container through the vent, and therefore, the end closures described by these publications do not substantially improve pourability. 
         [0007]    In addition, some separate vent apertures of the designs described by these publications require the use of a separate tool to open the vent aperture. Requiring a separate tool to open the vent aperture is inconvenient and requires the consumer to carry the tool to take advantage of any improved pour characteristics that may result from opening the separate vent aperture. Other examples of separate vent apertures of these designs are opened by aligning the tail or rear edge of the tab interconnected to the end closure with the vent aperture and then pressing the rear edge down onto the secondary score to sever the secondary score. The separate vent apertures designed to be opened in this manner can result in accidental opening of the vent aperture during shipment or storage if the tab or some other object presses against the secondary score. 
         [0008]    Still another design which attempts to improve end closure pourability includes a secondary gate or tear panel which is pushed into the container after the primary pour opening is opened. An example of this type of secondary vent is provided in U.S. Pat. No. 5,555,992 which is incorporated herein by reference in its entirety. In this design, secondary scores connect the secondary gate to the primary pour opening. However, once the primary pour opening is opened, the end panel becomes weak and deforms easily. End closures of this design do not have a large enough range of motion to overcome the flexing of the end closure panel and are difficult to open. Thus, this is not an effective design to improve the pourability of an end closure. 
         [0009]    Other end closure designs include a second opening connected to the pour opening. Some examples are provided in U.S. Pat. Nos. 3,762,597, 4,397,403, and 4,402,421 which are incorporated herein by reference in their entirety. End closures of these designs generally have a very narrow second opening which may not provide sufficient air flow into an interior of the container to improve flow rate of contents out of the container. In some cases, a lift ring used to open the pour opening is interconnected to the end closure over the pour opening and the lift ring must be pulled back to open the second opening before the product contained in the container can be consumed. 
         [0010]    Yet other designs for end closures attempt to improve pourability with a vent created by extending the score line of the pour opening past a bending plane of the tab. This creates a small area of air flow back into the container. This is the least effective design for improving pourability because of the limitation in the size of the vent due to tab functionality. Examples of these designs are provided in U.S. Pat. Nos. 4,289,251, 6,079,583, 7,975,884, and U.S. Patent Application Publication No. 2012/0031056, which are incorporated herein by reference in their entireties. 
         [0011]    These prior art designs fail to teach various novel features of the present invention. Furthermore, many previous attempts to improving pouring characteristics have involved major changes to the design of the container end closure, thus involving relatively high tooling or other equipment costs, design costs, testing costs and the like. Accordingly, there is an unmet need for a container end closure which improves pour rate, consistency, and smoothness of pour without requiring major changes to the design of the container or retooling during the manufacturing process. 
       SUMMARY OF THE INVENTION 
       [0012]    The present invention solves the aforementioned need by providing a metallic end closure with controlled venting. The following invention generally describes a metal end closure with a pull tab, a pour opening, and a secondary vent opening that address these long-felt needs. 
         [0013]    In one aspect of the present invention, a container end closure is provided with a pour opening portion and a secondary vent opening portion. The secondary vent opening portion may be selectively opened by a consumer to create improved flow characteristics due to a larger opened area and/or an area which allows for air intake into a container body through the secondary vent opening while enhancing the flow of contents of the container out of the pour opening. 
         [0014]    Container end closures of the present invention are adapted for interconnection with a neck of a container body. More specifically, a metallic end closure of the present invention generally comprises a peripheral curl which is adapted for interconnection to a neck of a container body, a chuck wall extending downwardly from the peripheral curl, a countersink comprised of an outer panel wall and an inner panel wall, and a central panel extending inwardly from the inner panel wall and countersink. For the purposes of further supporting and enabling the present invention, U.S. Pat. No. 7,506,779 to Jentzsch et al., entitled “Method and Apparatus for Forming a Reinforcing Bead in a Container End Closure,” and U.S. Pat. No. 7,100,789 to Nguyen et al., entitled “Metallic Beverage Can End With Improved Chuck Wall and Countersink,” are incorporated by reference herein in their entireties. 
         [0015]    It is another aspect of the present invention to provide an end closure with a secondary vent opening. The end closure generally comprises a peripheral curl adapted for interconnection to a neck of a container. A chuck wall is interconnected to the peripheral curl and extends downwardly therefrom. A countersink comprising an inner panel wall and an outer panel wall is interconnected to a lower portion of the chuck wall. A central panel is interconnected to the inner panel wall of the countersink. A pull tab generally comprising a forward edge and a rear edge is operably interconnected to the central panel by a rivet. In one embodiment, the pull tab further comprises an enlarged finger hole formed between the rivet and the rear edge of the pull tab. In another embodiment, the pull tab further comprises a grip area formed between the rivet and the rear edge of the pull tab, the grip area comprising at least one of ridges, grooves, bumps, protrusions, or other friction surfaces configured to facilitate grasping and pulling the pull tab. A first severable score line in the central panel is comprised of an origination point and a termination point. The first severable score line generally defines a first tear panel and a pour opening. A first hinge is positioned between the origination point and the termination point and is below the forward edge of the pull tab. A second severable score line is positioned in a right hemisphere of the central panel proximate to the first score and extends away from the first score at approximately a right angle. A third severable score line is positioned proximate to the first hinge and the first score line in a left hemisphere of the central panel. The second and third score lines generally extend away from the pour opening, the second score line in a substantially parallel orientation to the third score line. In one embodiment, the second score line is between approximately 0.375 inches and approximately 1.000 inches from the third score line at a point on a horizontal axis passing through the center of the central panel. In another embodiment, the second and third score lines have a minimum length of approximately 0.675 inches. In still another embodiment, the second and third score lines have a score residual thickness between approximately 0.0025 inches and approximately 0.0045 inches. In yet another embodiment, the second and third score lines flare outwardly to form termination features having a radius of curvature between approximately 0.060 inches and 0.500 inches. A second hinge is positioned between the second and third score lines, the second hinge generally comprising a form extending at least partially into the exterior surface of the end closure. The form can include any shape, channel, cut, groove, notch, recess, slot, depression, coining, and/or alteration to the surface of the central panel adapted to enable a second tear panel to bend or fold outwardly along the second hinge. In one embodiment, the form has a length of about 0.100 inches to about 1.00 inches. The secondary vent opening is defined by at least a portion of the first severable score line, the second severable score line, the third severable score line, and the second hinge, wherein the second and third score lines may be selectively severed to form the secondary vent opening by pulling the rear edge of the pull tab away from the first tear panel after the forward edge is used to sever the first tear panel. 
         [0016]    It is another aspect of the present invention to provide transition zones between the first severable score line and the second and third severable score lines. The transition zones prevent inadvertent or unintended opening of the secondary vent opening by preventing propagation of the first score line into the second or third score lines when the tab is utilized to open the pour opening. In one embodiment, the transition zones may comprise a variation in score residual depth between the depth of the first score and the depth of the second and third score. In another embodiment, the transition zones may generally comprise a score path of the second and third scores that connect the second and third scores tangentially to the fracture path of the first score. In still another embodiment, the transition zones may generally comprise a score deviation such as a small, narrow coin located proximate to the first score and perpendicular to the score paths of the second and third scores. In yet another embodiment, the transition zones may generally comprise a small void region located approximately between the first score and the origination points of the second and third scores. 
         [0017]    Various secondary vent opening geometries are contemplated. For example, in one embodiment the second and third score lines are substantially parallel to a vertical Y-axis that bisects the end closure. In some embodiments, the second and third score lines may have a curvilinear shape. Further, in still more embodiments, the second and third score lines are substantially symmetrical about the Y-axis. In yet another embodiment, the second and third score lines are not symmetrical about the Y-axis. The shape of the secondary vent opening may be selected based on the desired flow rate, the ease of fracturing the second and third score lines, and score termination features that prevent the second tear panel from being removed or separated from the end closure. The location of beginning and end points of the second and third score lines can vary as well. In some embodiments, the third score line may begin near the left transition zone located between the center of the end closure and the radially inner portion of the first hinge of the first tear panel. In other embodiments, the third score line may begin near the left transition zone which may be located between the central panel outer perimeter and the radially outer portion of the first hinge of the first tear panel. In yet another embodiment, the third score line may begin between the radially inner portion of the first hinge and the radially outer portion of the first hinge. 
         [0018]    It is another aspect of the present invention to provide a tab which is capable of opening the first tear panel defined within the first score line through a first opening movement or lifting of the rear edge of the tab, and subsequently capable of being utilized to open the secondary vent opening through a second opening movement. In one embodiment, the tab is generally the same size and external profile of known Stolle style tabs wherein a non-voided area is provided in place of the finger hole on the rear edge of the tab. The non-voided area may have a series of bumps, ridges, or other grip features to help the consumer grasp and pull the tab back. In another embodiment, the tail or rear edge of the tab may have generally the same shape as known ring pull tabs but the tab may be provided with the nose end or forward edge of a stay-on-tab (SOT) style tab that is used to push in the first tear panel of the pour opening. 
         [0019]    It is another aspect of the present invention to provide an end closure with a pour opening and a secondary vent opening wherein the consumer can selectively determine whether to utilize the secondary vent opening for venting, or drink from the container in a conventional manner from the pour opening without the increased flow resulting from opening the secondary vent opening. Stated differently, the pour opening of the present invention may operate even if the secondary vent opening is not opened. Thus, in one embodiment, the pour opening and the secondary vent opening may be opened in series through the application of one or more forces, wherein the force used to open the secondary vent opening is distinct from the force used to open the pour opening. In one embodiment, the secondary vent opening may not be opened without first opening the pour opening. Further, the secondary vent can be selectively opened only partially or fully depending on the preference of the consumer. 
         [0020]    It is another aspect of the present invention to provide a method of manufacturing a metallic end closure with a secondary vent. This includes, but is not limited to, a method generally comprising: (1) cutting a metal blank from a continuous roll of a sheet metal material; (2) forming an end closure from the metal blank, the end closure comprising a chuck wall extending downwardly from a peripheral curl, a countersink interconnected to a lower end of the chuck wall, and a central panel interconnected to the countersink; (3) forming a first severable score line in the central panel, the first severable score line having an origination point and a termination point, wherein the first severable score line defines a first tear panel and a first hinge, and wherein the first tear panel defines a pour opening; (4) forming a second severable score line in the central panel, the second severable score line positioned proximate to the first score line on a first side of a vertical axis passing through a center of the central panel, the second severable score line extending away from the first score line at approximately a right angle; (5) forming a third severable score line in the central panel, the third severable score line positioned proximate to the first score line and the first hinge, the third severable score line positioned on a second side of the vertical axis, the third severable score line extending away from the first hinge, the third score line substantially symmetric to the second score line; (6) forming a second hinge in the central panel, the second hinge positioned between the second score line and the third score line; and (7) interconnecting a pull tab having a forward edge and a rear edge to the central panel, wherein the pull tab is substantially centered on the central panel, wherein the first tear panel is positioned below the forward edge of the pull tab, and wherein the second hinge and the second and third score lines define a second tear panel and the secondary vent when the pull tab is pulled away from the pour opening. One example of the general geometry of a metallic end closure is described in U.S. Patent Application Publication No. 2013/0118133, which is incorporated herein by reference in its entirety. 
         [0021]    Optionally, the method may further comprise (8) forming a second score line termination feature and a third score line termination feature, wherein the second score line termination feature and the third score line termination feature are adapted to prevent the second tear panel from detaching from the central panel; and (9) forming transition portions between the first score line and the second and third score lines, wherein the transition portions are adapted to prevent a fracture propagation of the first score line into the second and third score lines. The second hinge comprises a form extending at least partially into a public side of the end closure. In one embodiment, the form of the second hinge is positioned approximately 0.500 inches to approximately 0.850 inches from the center of the end closure. In another embodiment, the form has a depth between approximately 0.001 inches and 0.030 inches and a length of between approximately 0.100 inches and approximately 1.00 inches. In yet another embodiment, the second score line and the third score line have a score residual thickness of between approximately 0.0025 inches and approximately 0.0045 inches. In still another embodiment, the second tear panel has an area no less than an area of the first tear panel. The transition portions comprise at least one of a score deviation in the second and third score lines, a void area between the first score line and the second and third score lines, a variation in residual depth of the first score line and the second and third score lines, and a score path of the second and third score lines oriented tangentially to a direction of fracture of the first score line. 
         [0022]    Another aspect of the present invention is to provide a method of opening a beverage container with a pour opening and a secondary vent opening. The method includes, but is not limited to (1) providing the container body with a lower end with a support surface and a neck on an upper end; (2) providing a metallic end closure with a peripheral curl interconnected to the neck of the container, a chuck wall, a countersink, and a central panel; (3) providing the pour opening in the central panel with a first area defined by a first score and a first hinge; (4) providing the secondary vent opening in the central panel defined by a portion of the first score, a second score, a third score, and a second hinge, the secondary vent opening generally comprising a second area equal to or greater than the first area; (5) providing a pull tab with a forward edge and a rear edge, the pull tab operably interconnected to the central panel, the interconnection substantially centered on the central panel, the forward edge positioned over at least a portion of the first tear panel; (6) pulling the rear edge to drive the forward edge into the first tear panel to shear the first score and create the pour opening; and (7) optionally pulling the rear edge away from the pour opening to sever the second score and the third score to create the secondary vent opening, wherein air is allowed to ingress into the secondary vent opening while product is being dispensed from the pour opening. 
         [0023]    In yet another aspect of the present invention, a container end closure with a pour opening and a secondary vent opening is provided which improves the consumer&#39;s ability to smell the product contained in a container during dispensing. The secondary vent opening may increase air flow out of the container with the end closure of the present invention. When the consumer drinks from the container, the secondary vent is located in close proximity to the consumer&#39;s nose, thus expelled air caused by the dispensing of the liquid travels straight to the consumer&#39;s nose. This improves the consumer&#39;s perception of the taste of the product because research shows that a product&#39;s taste is greatly enhanced by the scent of the product. 
         [0024]    The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements or components. Additional aspects of the present invention will become more readily apparent from the Detailed Description, particularly when taken together with the drawings. 
         [0025]    The above-described embodiments, objectives, and configurations are neither complete nor exhaustive. As will be appreciated, other embodiments of the invention are possible using, alone or in combination, one or more of the features set forth above or described in detail below. 
         [0026]    The phrases “at least one,” “one or more,” and “and/or,” as used herein, are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B, and C,” “at least one of A, B, or C,” “one or more of A, B, and C,” “one or more of A, B, or C,” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B, and C together. 
         [0027]    Unless otherwise indicated, all numbers expressing quantities, dimensions, conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” 
         [0028]    The term “a” or “an” entity, as used herein, refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more,” and “at least one” can be used interchangeably herein. 
         [0029]    The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Accordingly, the terms “including,” “comprising,” or “having” and variations thereof can be used interchangeably herein. 
         [0030]    It shall be understood that the term “means” as used herein shall be given its broadest possible interpretation in accordance with 35 U.S.C., Section  112 ( f ). Accordingly, a claim incorporating the term “means” shall cover all structures, materials, or acts set forth herein, and all of the equivalents thereof. Further, the structures, materials, or acts and the equivalents thereof shall include all those described in the summary of the invention, brief description of the drawings, detailed description, abstract, and claims themselves. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0031]    The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the Summary of the Invention given above and the Detailed Description of the drawings given below, serve to explain the principles of these embodiments. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. Additionally, it should be understood that the drawings are not necessarily to scale. 
           [0032]      FIG. 1  is a top plan view of a prior art end closure interconnected to a neck of a container, wherein the end closure has a secondary vent panel connected to a tear panel; 
           [0033]      FIG. 2  is a top plan view of another prior art end closure interconnected to a neck of a container, wherein a secondary vent panel is formed near the perimeter of a central panel of the end closure and the secondary vent panel is not connected to a primary pour tear panel; 
           [0034]      FIG. 3  is a top plan view of an end closure segmented into four quadrant zones; 
           [0035]      FIG. 4  is a top plan view of a container end closure interconnected to a neck of a container according to one embodiment of the present invention, wherein a first tear panel and a second tear panel are in a closed configuration; 
           [0036]      FIG. 5A  is a partially fragmented cross-sectional elevation view of the container end closure of  FIG. 4  taken along line  5 A; 
           [0037]      FIG. 5B  is a partially fragmented cross-sectional elevation view of the container end closure of  FIG. 4  taken along line  5 B; 
           [0038]      FIG. 5C  is perspective view of the container end closure and container of  FIG. 4  with the first tear panel and second tear panel in an open configuration; 
           [0039]      FIG. 6A  is a top plan view of a container end closure interconnected to a neck of a container according to another embodiment of the present invention, wherein a first tear panel and a second tear panel are in a closed configuration; 
           [0040]      FIG. 6B  is perspective view of the container end closure and container of  FIG. 6A  with the first tear panel and second tear panel in an open configuration; 
           [0041]      FIG. 7  is a top plan view of a container end closure interconnected to a neck of a container according to yet another embodiment of the present invention with a first tear panel and a second tear panel in a closed configuration; and 
           [0042]      FIG. 8  is a top plan view of a pull tab according to one embodiment of the present invention. 
       
    
    
       [0043]    Similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a letter that distinguishes among the similar components. If only the first reference label is used, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label. 
         [0044]    A list of the various components shown in the drawings and associated numbering is provided herein: 
         [0000]    
       
         
               
               
             
               
               
             
           
               
                   
               
               
                 Number 
                 Component 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1 
                 Container 
               
               
                 2 
                 End closure 
               
               
                 4 
                 Secondary vent panel 
               
               
                 6 
                 Container body 
               
               
                 7 
                 Neck 
               
               
                 8 
                 Pour tear panel 
               
               
                 10 
                 End closure 
               
               
                 12 
                 Secondary vent panel 
               
               
                 14 
                 Container end closure 
               
               
                 17 
                 Central panel 
               
               
                 18 
                 First score 
               
               
                 20 
                 Debossed area 
               
               
                 21 
                 Pour opening 
               
               
                 22 
                 First tear panel 
               
               
                 23 
                 Debossed area depth 
               
               
                 24 
                 Tab 
               
               
                 26 
                 Rivet 
               
               
                 30 
                 Pivot point 
               
               
                 32 
                 Rear edge 
               
               
                 34 
                 Forward edge 
               
               
                 35  
                 Open area 
               
               
                 36 
                 First hinge 
               
               
                 40 
                 Countersink 
               
               
                 48 
                 Peripheral seam 
               
               
                 50 
                 Panel outer perimeter 
               
               
                 52 
                 X-axis 
               
               
                 54 
                 Y-axis 
               
               
                 56  
                 Upper right quadrant 
               
               
                 57  
                 Lower right quadrant 
               
               
                 58  
                 Lower left quadrant 
               
               
                 59 
                 Upper left quadrant 
               
               
                 60 
                 Third score 
               
               
                 62 
                 Score residual 
               
               
                 64 
                 Left transition zone 
               
               
                 66  
                 Score separation distance 
               
               
                 68 
                 Second score 
               
               
                 72 
                 Right transition zone 
               
               
                 76 
                 Secondary vent opening 
               
               
                 78  
                 Second tear panel 
               
               
                 80  
                 Score termination feature 
               
               
                 84  
                 Third score end 
               
               
                 88  
                 Second score end 
               
               
                 90  
                 Second hinge 
               
               
                 92  
                 Hinge length 
               
               
                 94  
                 Form 
               
               
                 96 
                 Public side 
               
               
                 98 
                 Form width 
               
               
                 100 
                 Form depth 
               
               
                 102 
                 Distance to second hinge 
               
               
                 104 
                 Distance to exterior of container body 
               
               
                   
               
             
          
         
       
     
       DETAILED DESCRIPTION 
       [0045]    The present invention has significant benefits across a broad spectrum of endeavors. It is the Applicant&#39;s intent that this specification and the claims appended hereto be accorded a breadth in keeping with the scope and spirit of the invention being disclosed despite what might appear to be limiting language imposed by the requirements of referring to the specific examples disclosed. To acquaint persons skilled in the pertinent arts most closely related to the present invention, a preferred embodiment that illustrates the best mode now contemplated for putting the invention into practice is described herein by, and with reference to, the annexed drawings that form a part of the specification. The exemplary embodiment is described in detail without attempting to describe all of the various forms and modifications in which the invention might be embodied. As such, the embodiments described herein are illustrative, and as will become apparent to those skilled in the arts, may be modified in numerous ways within the scope and spirit of the invention. 
         [0046]    Although the following text sets forth a detailed description of numerous different embodiments, it should be understood that the detailed description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims. To the extent that any term recited in the claims at the end of this patent is referred to in this patent in a manner consistent with a single meaning, that is done for sake of clarity only so as to not confuse the reader, and it is not intended that such claim term by limited, by implication or otherwise, to that single meaning. 
         [0047]    Various embodiments of the present invention are described herein and as depicted in the drawings. It is expressly understood that although the figures depict metal end closures with embodiments of a secondary vent opening, the present invention is not limited to these embodiments. 
         [0048]    Referring now to  FIG. 1 , a top plan view of a prior art end closure  2  interconnected to a body  6  of a container  1  is illustrated. The end closure  2  has a secondary vent panel  4  which is connected to a pour tear panel  8 . The pour tear panel  8  and secondary vent panel  4  are illustrated in a closed configuration. A tab  24  is used to open the container by severing scores that form the pour tear panel  8  and the secondary vent panel  4 . The tab  24  is coupled to the end closure  2  by a rivet  26  whose center defines a pivot point  30 . Generally, lifting the rear edge  32  of the tab  24  up and away from the end closure  2  results in the forward edge  34 , or nose, of the tab  24  pressing downward on a part of the pour tear panel  8  with sufficient force to cause a rupture to form along the severable score that forms the pour tear panel  8 . The rupture of the severable score permits the pour tear panel  8  to bend inward into the container  1  to create a pour opening. The tab  24  is then bent back down generally parallel to the exterior surface of the end closure  2 . Next, the tab  24  is rotated clockwise around the pivot point  30  to align the forward edge  34  of the tab  24  over the secondary vent panel  4 . The rear edge  32  of the tab  24  is lifted again to drive the forward edge  34  into the secondary vent panel  4  to bend the secondary vent panel  4  inward to enlarge the pour opening. 
         [0049]    A top plan view of another prior art end closure  10  interconnected to a body  6  of a container  1  is illustrated in  FIG. 2 . The end closure  10  has a pour tear panel  8  and a secondary vent panel  12  which are in an initial closed configuration. The secondary vent panel  12  is formed on the end closure  10  at a position separate from the pour tear panel  8 . The pour tear panel  8  is opened with a tab  24  as described in conjunction with  FIG. 1 , above. After the pour tear panel  8  is opened, the secondary vent panel  12  may be opened by rotating the tab  24  clockwise to position a rear edge  32  of the tab  24  over the secondary vent panel  12 . The rear edge  32  is then pressed downward and against the secondary vent panel  12  to rupture the severable score and bend the secondary vent panel  12  into the container  1  to create a secondary vent opening. Optionally, the secondary vent panel  12  may be opened by pressing a tool against the secondary vent panel  12  to bend it into the container  1 . 
         [0050]    Referring now to  FIG. 3 , a top plan view is provided of a container end closure  14  segmented into four quadrant zones. The quadrant zones are used for description purposes and may be referenced throughout the disclosure. As shown in  FIG. 3 , the end closure  14  has an X-axis  52  and a Y-axis  54  defining an upper right quadrant  56 , a lower right quadrant  57 , a lower left quadrant  58 , and an upper left quadrant  59 . 
         [0051]    Referring now to  FIG. 4 , a top plan view of a container  1  with a metal end closure  14  according to one embodiment of the present invention is provided. The end closure  14  is interconnected to a neck  7  of a container body  6 . The end closure  14  has a central panel  17  with an outer perimeter or circumference  50  and a countersink  40 . The countersink generally comprises an inner panel wall and an outer panel wall, which is in turn interconnected to a chuck wall and a peripheral seam  48 . Before double seaming to the container body  6 , the end closure  14  has an outer edge formed into a peripheral curl. Upon interconnection to the container body  6 , the peripheral curl is formed into the peripheral seam  48 . 
         [0052]    The central panel  17  has a recessed or debossed area  20  with a first tear panel  22  associated with a first score  18  and a first hinge  36 . The first tear panel  22  is generally located in lower quadrants  57 ,  58  and is illustrated in  FIG. 4  in a closed configuration. Although the first tear panel  22  as shown is generally elliptically shaped, it should be understood that the first tear panel  22  may have any shape selected for pour characteristics, including a circular or oval shape, or any combination thereof. As will be understood by one of ordinary skill in the art, the first hinge  36  may be positioned on either side of the Y-axis  54 . A tab (not illustrated in  FIG. 4 ) is interconnected to the end closure  14  by a rivet  26 . The rivet  26  is generally centered on the end closure  14  at the intersection of the X-axis  52  and the Y-axis  54 , although it may be off-set along the Y-axis  54 . The tab is positioned to bend the first tear panel  22  inward to open the container  1  as described above with respect to  FIG. 1 . 
         [0053]    A second score line  68  intersects the first score line  18  at approximately a right angle near a right transition zone  72  on the right side of the Y-axis  54 . A third score line  60  intersects the first score line  18  near a left transition zone  64  near the hinge  36  on the left side of the Y-axis  54 . The second score  68  and the third score  60  extend away from the first score line  18  across the end closure  14  into the upper quadrants  56 ,  59  to end  88  and end  84 . The second score  68  and the third score  60  define a second tear panel  78 . In one embodiment, the scores  60 ,  68  have a minimum length of approximately 0.675 inches. In the embodiment illustrated in  FIG. 4 , score lines  60 ,  68  are substantially parallel to the Y-axis  54 . One of ordinary skill in the art will appreciate, however, that the location, shapes, beginning points, and end points of score lines  60 ,  68  may be altered and/or repositioned in a variety of ways. It will also be recognized by one skilled in the art that the score design of the first score line  18  and scores  60 ,  68  require careful balancing of dimensions and design parameters in order to ensure that the first tear panel  22  and the second tear panel  78  and other portions of the central panel remain closed at appropriate times (e.g., during packaging and shipping operations) and yet will open under a reasonable amount of consumer-applied force. 
         [0054]    The transition zones  64 ,  72  of the present invention generally comprise areas that inhibit fracture propagation of the score  18  into the second score  68  and the third score  60  and thus may prevent the unintentional or inadvertent opening of the second tear panel  78 . In one embodiment, transition zones  64 ,  72  of the present invention may terminate propagation of the first score  18  fracture due to a variation in residual depth of score  18  and residual depth of scores  60 ,  68 . For example, the score residual thickness  62  of scores  60 ,  68  may be about 0.0005 inches less than the score residual thickness of score  18 . In another embodiment, the transition zones  64 ,  72  may comprise a score path that connects the scores  60 ,  68  tangentially to the first score  18  from a direction of the fracture path of the first score  18 . In another embodiment, the transition zones  64 ,  72  may be defined by a predetermined void distance between the first score  18  and scores  60 ,  68 . For example, a small void consisting of an unscored area of the end closure  14  may be left between each of scores  60 ,  68  and the first score  18  to form the transition zones  64 ,  72 . In another embodiment, the transition zones  64 ,  72  may comprise a score deviation similar to an anti-missile feature. The score deviation may be a small, narrow coin located proximate to the first score  18  and perpendicular to the path of each of the scores  60 ,  68 . The score deviation may also be an interference in the path of score  18  or scores  60 ,  68  such as a check slot. In a further embodiment, plastisol or other adhesives may also be used to minimize the chance of inadvertent fracture of scores  60 ,  68 . 
         [0055]    Score termination features  80  of the present invention are provided to generally define or limit the propagation of scores  60 ,  68  and to create a desired shape for the second tear panel  78 . In one embodiment shown in  FIG. 4 , the score termination features  80  comprise curved segments near score ends  84 ,  88 . The curved segments represent a departure from the general path of the scores  60 ,  68  and space score ends  84 ,  88  apart. The curved segments flare radially outwardly to direct the path of the scores  60 ,  68  toward the panel outer perimeter  50  and prevent the second tear panel  78  and the tab from detaching from the end closure  14 . In one embodiment, the score termination features  80  of the present invention may generally comprise curved segments with a radius of curvature between approximately 0.060 inches and approximately 0.500 inches. In a preferred embodiment, the radius of curvature of the curved segment may be between approximately 0.217 inches and approximately 0.437 inches. In a more preferred embodiment, the radius of curvature of the curved segment may be approximately 0.375 inches. 
         [0056]    A second hinge  90  may optionally be formed between scores  60 ,  68 . The second hinge  90  may be generally perpendicular to the Y-axis  54  and have a length  92  extending at least partially into upper quadrants  56 ,  59 . In one embodiment, the length  92  of the second hinge  90  may be between approximately 0.100 inches and approximately 1.0 inches. In a preferred embodiment, the length  92  of the second hinge  90  may be between approximately 0.300 inches and approximately 0.750 inches, and in a more preferred embodiment, the length  92  of the second hinge  90  may be approximately 0.500 inches. In one embodiment, the second hinge  90  may be formed a distance  102  from a center of rivet  26  equal to approximately one-half of the distance  104  from a point tangent to an exterior surface of the container body  6  to the center of the rivet  26 . In a preferred embodiment, the distance  102  between the second hinge  90  and the center of the rivet  26  may be between approximately 0.500 inches and approximately 0.850 inches. In a more preferred embodiment, the distance  102  between the second hinge  90  and the center of rivet  26  may be approximately 0.675 inches. One of skill in the art will recognize that the second hinge  90  could be formed closer to the rivet  26  or further from the rivet  26 . Although various dimensions are described to illustrate exemplary embodiments and locations of the second hinge  90 , it is expressly contemplated that dimensions, shapes, and locations of the second hinge  90  and the form  94  may be varied and still comport with the scope and spirit of the present invention. 
         [0057]    In general, the second hinge  90  may be formed to make the second tear panel  78  easier to open and to provide an area to fold the second tear panel  78  back over the container end closure  14 . No rupture occurs along the second hinge  90  during a normal opening sequence. 
         [0058]    Referring now to  FIG. 5A , a partially fragmented cross-sectional elevation view taken along line  5 A of  FIG. 4  is illustrated with the tab removed for clarity. The debossed area  20  generally has a depth  23  of between approximately 0.005 inches and approximately 0.025 inches. The second score  68  and third score  60  generally have a score residual thickness  62  of between approximately 0.0025 inches and approximately 0.0045 inches. The centerlines of scores  60 ,  68  are separated by a distance  66  of between approximately 0.375 inches and approximately 1.000 inches. Although various dimensions are provided to illustrate one exemplary embodiment of the present invention, the present invention is not limited to these dimensions and it is expressly contemplated that the depth  23  of the debossed area  20 , the score residual thickness  62  of the scores  60 ,  68 , and the distance  66  between the scores  60 ,  68  may be varied and still conform with the scope and spirit of the present invention. 
         [0059]    Referring now to  FIG. 5B , a partially fragmented cross-sectional elevation view of the container end closure  14  taken along line  5 B of  FIG. 4  is illustrated. As illustrated in  FIG. 5B , in one embodiment the second hinge  90  generally comprises a form  94  extending at least partially into the exterior or public side  96  of the end closure  14 . The form  94  can include any shape, channel, cut, score, anti-fracture score, groove, notch, recess, slot, depression, coining, and/or alteration to the public side  96  of the central panel  17  adapted to enable the second tear panel  78  to bend or fold outwardly along the second hinge  90 . The form  94  has a width  98  and a depth  100 . In one embodiment, the width  98  of the form  94  may be between approximately 0.025 inches and approximately 0.250 inches. In a preferred embodiment, the width  98  may be between approximately 0.062 inches and approximately 0.175 inches. In a more preferred embodiment, the width  98  of the form  94  may be approximately 0.100 inches. 
         [0060]    The depth  100  of the form  94  may be between approximately 0.001 inches and approximately 0.030 inches in one embodiment. In a preferred embodiment, the depth  100  may be between approximately 0.005 inches and approximately 0.02 inches. In a more preferred embodiment, a form  94  of the present invention generally comprises a depth  100  of approximately 0.010 inches. Optionally, the second hinge  90  may be formed by the score termination features  80  of the score ends  84 ,  88 . For example, the score termination features  80  of the scores  60 ,  68  may be configured to form the second hinge  90  without the use of the form  94 . 
         [0061]    Referring now to  FIG. 5C , a perspective view of the container end closure  14  in an open configuration is provided and shown interconnected to a typical beverage container  1 . As shown, the first tear panel  22  has been bent inwardly at the first hinge  36  into the container  1  to open the pour opening  21 . The first tear panel  22  remains connected to the end closure  14  by the first hinge  36 . After the pour opening  21  is opened, the tab  24  is pulled away from the pour opening  21  to sever the second and third scores to open the secondary vent opening  76 . The second tear panel  78  is retained by the second hinge  90  and is bent over the peripheral seam  48 . In one embodiment, the first tear panel  22  has an area or an openable area of approximately 0.500 inches. In another embodiment, the openable area of the first tear panel  22  may be approximately 0.700 inches. In one embodiment, an area or an openable area of the second tear panel  78  is equal to or greater than the area of the first tear panel  22  so that a rate or volume of air entering the container equals a second rate or volume of product leaving the container  1  when the product is poured from the container. In one embodiment, when completely opened by a consumer, the combined area of the pour opening  21  and the secondary vent opening  76  have an area of approximately one-third of a total surface area of the end closure  14 . However, as will be appreciated by one of ordinary skill in the art, the first tear panel  22  and the second tear panel  78  may be varied in size. As will be recognized by one of ordinary skill in the art, area as used herein refers to the surface area of first and second tear panels  22 ,  78  and the pour opening  21  and the secondary vent opening  76  as defined by their respective score lines as shown and described herein. 
         [0062]    Referring now to  FIG. 6A , a top plan view of an embodiment of an end closure  14  with a modified second tear panel  78 A is illustrated. The end closure  14  is interconnected to the neck  7  of a container  1 . The first tear panel  22 A is defined by the first score  18  and the first hinge  36  in the lower quadrants  57 ,  58 . A second score line  68 A begins proximate the first score line  18  at approximately a right angle near a right transition zone  72 A. A third score  60 A begins proximate the first score line  18  near a left transition zone  64 A. The left transition zone  64 A is positioned radially outside the first hinge  36  on the left side of the Y-axis  54 . Stated otherwise, the left transition zone  64 A is located between the hinge  36  and the outer perimeter  50  of the central panel  17 . In one embodiment, the left transition zone  64 A may be located further from the rivet  26  than the right transition zone  72 A. The score lines  60 A,  68 A have a generally curvilinear shape and extend away from the first score line  18  across the end closure  14  into the upper quadrants  56 ,  59  to ends  84 A,  88 A. In one embodiment, the scores  60 A,  68 A have a minimum length of approximately 0.675 inches. 
         [0063]    Score termination features  80 A comprise curved segments near score ends  84 A,  88 A. The score termination features  80 A flare radially outwardly to direct the path of the scores  60 A,  68 A toward the panel outer perimeter  50  to prevent the second tear panel  78 A from detaching from the end closure  14 . The score termination features  80 A may generally comprise curved segments with a radius of curvature between approximately 0.060 inches and approximately 0.500 inches. In a preferred embodiment, the radius of curvature of the curved segment may be between approximately 0.217 inches and approximately 0.437 inches. In a more preferred embodiment, the radius of curvature of the curved segment may be approximately 0.375 inches. Although a second hinge  90  is not illustrated in  FIG. 6A , a second hinge  90  may optionally be positioned approximately between score ends  84 A,  88 A.  FIG. 6A  also illustrates a modified debossed area  20 A generally comprising a different, optional shape compared to the debossed area  20  of the embodiment illustrated in  FIG. 4 . 
         [0064]    Referring now to  FIG. 6B , a perspective view of the container end closure  14  and container  1  of  FIG. 6A  are illustrated with the first tear panel  22 A and second tear panel  78 A in an open configuration. The first tear panel  22 A is initially bent inwardly at the first hinge  36  into the container  1  to open the pour opening  21 A. After the pour opening  21 A is opened, the tab  24  is pulled away from the pour opening  21 A to sever the second and third scores to open the secondary vent opening  76 A. The first tear panel  22 A is connected to the second tear panel  78 A at the first hinge  36  and is pulled out of the container  1  when the secondary vent opening  76 A is opened. The first and second tear panels  22 A,  78 A remain connected to the end closure  14  and are bent over the peripheral seam  48 . 
         [0065]      FIG. 7  illustrates another embodiment of second tear panel  78 B formed in an end closure  14 . The end closure  14  is interconnected to a container  1  at a neck  7  of the body  6 . A first tear panel  22  is formed in the lower quadrants  57 ,  58  by a first score  18  and a first hinge  36 . As shown, a second score  68 B begins on the right side of the Y-axis  54  near the right transition zone  72 B. The second score  68 B is substantially perpendicular to the first score  18 . A third score  60 B begins on the left side of the Y-axis  54  proximate the first score  18  near a left transition zone  64 B. In the embodiment illustrated in  FIG. 7 , the left transition zone  64 B is positioned radially inward of the first hinge  36  between the first hinge  36  and the rivet  26 . Although not illustrated in  FIG. 7 , a second hinge  90  comprising a form  94  may optionally be positioned between scores  60 B and  68 B. In one embodiment, the second hinge  90  is positioned between score ends  84 B,  88 B and extends into the upper quadrants  56 ,  59 . The second hinge  90  is generally perpendicular to the Y-axis  54 . The second hinge  90  may have the dimensions described in conjunction with  FIGS. 4 and 5B . Further, although no debossed area  20  is illustrated in  FIG. 7 , a debossed area  20  may be formed in the end closure  14  of any shape, such as a size and shape similar to the debossed area  20  illustrated in  FIG. 4  or the debossed area  20 A illustrated in  FIG. 6A , or a combination of the shapes of debossed areas  20  and  20 A. When the end closure  14  is opened, the first tear panel  22  is pressed into the container  1  and is retained within the container by the first hinge in a manner similar to the end closure illustrated in  FIG. 5C . After the first tear panel  22  is pressed into the container  1 , the tab may be pulled backwardly toward the upper quadrants  56 ,  59  to sever the second score  68 B and the third score  60 B. The second tear panel  78 B and the tab are then bent over the peripheral seam  48  similar to the embodiment of the second tear panel  78  illustrated in  FIG. 5C . 
         [0066]      FIG. 8  illustrates a stay-on ring pull tab  24 A in one embodiment of the present invention. The ring pull tab  24 A is generally larger than a conventional pull tab  24  as illustrated in  FIG. 1 . The increased size is provided in some embodiments to allow an improved gripping area for a user to grasp while opening the secondary vent opening. The tab  24 A has a rear edge  32 A, a forward edge  34 A, and an optional open area  35  forming a loop. In one embodiment, the open area  35  of the tab  24 A may be enclosed to form a grip area (not illustrated). A series of ridges, grooves, bumps, protrusions, or other friction surfaces selected to facilitate grasping and pulling of the tab  24 A by the consumer are formed in the grip area. The material of the grip area may differ from the material of the tab  24 A. For example, the grip area may include rubber, plastic, and/or any other materials selected improve friction between a consumer&#39;s finger and the tab  24 A. 
         [0067]    In operation, the method of opening an end closure of the present invention is similar to the method used to open known container ends with stay-on-tabs. Further, because the tab of the present invention is familiar to consumers there is little requirement to educate consumers on the method of opening the pour opening and secondary vent of the end closure of the present invention. 
         [0068]    To open the pour opening and secondary vent opening, the rear edge  32  of the tab  24  is pulled upward by the consumer causing the forward edge  34  to apply a downward force to the first tear panel  22 . The downward force of the forward edge  34  severs the first score  18  and opens the pour opening  21  as the tear panel  22  is pushed down, pivoting away from the consumer at the first hinge  36  into the container  1 . At this point, the consumer can consume the beverage in the container  1  much like in a container with a prior art end closure by pushing the tab  24  back down into its initial position substantially parallel to the end closure  14 . Alternatively, while the tab  24  is still pulled up at an angle compared to the end closure  14 , the consumer can pull the tab  24  back away from the pour opening  21 , toward the upper quadrants  56 ,  59  tearing score lines  60 ,  68 . As the score lines  60 ,  68  are torn by the pulling force, the second tear panel  78  is pulled up and back to open the secondary vent opening  76 . The tab  24  and the second tear panel  78  can then be folded back over an edge formed by the peripheral seam  48  away from the consumer. In the embodiments illustrated in  FIGS. 4 and 7 , the first tear panel  22  remains attached to the end closure  14  and is pressed into the interior of the container under the central panel  17  separate from the second tear panel  78  as illustrated in  FIG. 5C . In the embodiment illustrated in  FIG. 6A , the first tear panel  22 A is connected to second tear panel  78 A by the first hinge  36 . When the tab  24  is pulled back to sever scores  60 A,  68 A, the first tear panel  22  is pulled up and out of the pour opening  21  with the second tear panel  78 A when the secondary vent opening  76 A is opened as shown in  FIG. 6B . Alternatively, the consumer can select to open the secondary vent only a partial amount rather than the full amount, based on personal preference. 
         [0069]    In practice, a container end closure of the present invention may be formed by providing a generally flat blank according to procedures well known in the art. A die may be used to stamp the container end closure providing scores configured as depicted in the Figures and, preferably, other features such as reinforcing beads or other reinforcements and the like. A tab is interconnected to the container end closure generally as provided in previous procedures well known to those of skill in the art. The container end closure thus formed may be coupled to a container body, formed according to procedures known to those of skill in the art, to provide a complete container. 
         [0070]    Producing container end closures in the manner and form of the present invention can be achieved using materials and apparatus generally similar to that used in previous procedures for forming container end closures such as those depicted in  FIGS. 1 and 2 . A die or other scoring device can be configured to provide the first score  18  and scores  60 ,  68  and, optionally, the second hinge  90  as depicted in  FIGS. 1-7 . Optionally, reinforcing or other features may be formed on the end closure. In this way, it is possible to implement the present invention with few changes to previous procedures and apparatus thus minimizing or reducing costs associated with retooling, procedural changes, testing and the like. Of course, if desired, it is possible to use the present invention in connection with different container or container end closure designs, shapes, or sizes. 
         [0071]    The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limiting of the invention to the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments described and shown in the figures were chosen and described in order to best explain the principles of the invention, the practical application, and to enable those of ordinary skill in the art to understand the invention. 
         [0072]    While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. It is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims.