Abstract:
A self-closing resealable can end for a beverage container that opens the top of the beverage container through downward pressure that causes a gate to move downward relative to the top panel. The gate is retained by a resilient member and when the downward pressure ceases, the gate is moved into proximity with the top panel. Pressure from the carbonation presses the gate against a lip and the gate bends to form an enhanced seal. Other variations are disclosed.

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/965,363, filed Aug. 20, 2007, titled “Article of manufacture for a self-closing vented self-resealing beverage can-end.” 
    
    
     FIELD OF INVENTION 
     This invention relates generally to the field of beverage containers, and more particularly to an article of manufacture for an easy-open, self-closing vented, user lip actuated, conical gate opening in a carbonated beverage can-end which automatically sequences to gas-tight self-resealing mode upon carbonated content agitation. 
     Where the words “upwardly,” “downwardly,” “inwardly,” “outwardly,” “under,” “underside,” “and like words of orientation are used in this application, unless specifically indicated to the contrary, they are to be applied with reference to a can or other container standing on its base in an upright position having a can-end incorporating this invention attached to the top end thereof. 
     BACKGROUND 
     When cans became popular for containing beverages openers were needed; subsequently opening tabs were provided in the can-ends and the removable ring-pull tab became very popular. The ring-pull tab evolved into the non-removable stay-tab and hinged non-removable push-down gates to solve the problems of ring-pull tab litter and exposed sharp can opening edges. Exemplary of hinged push-down gates is the triple-fold gate disclosed in U.S. Pat. No. 3,334,795 and U.S. Pat. No. 4,215,792. The basic purpose of these two patents was to provide a one-piece easy-open hinged can top without the need for opening attachments like tabs, levers, and cams. Other types of gated can-ends are also available and the general basic construction of any gated can-end is to provide a gate which is slightly larger than and underlies an opening or aperture in the can-end. The gate, hinged to the can-end at an edge portion of the opening, remains attached to the end when pushed downward into the can to open it. 
     Prior technology can-ends do not address the problems with spilling, contamination, and gas charge preservation in an economically manufacturable and/or practicable design. Either too much energy and time is needed to form the material, too much material is required to manufacture the can-end, or the can-end design interferes with efficient recyclables, standard packaging, vending machine dimensions, and stackability; or requires the user to hand-operate a device to reseal and reopen the can opening between each sip, if immanently in danger of being contaminated by insects, sand, rain, soap, or other contaminants. The current flip-top is also difficult to open without breaking long fingernails and difficult for young children to open. 
     SUMMARY 
     The present invention provides a push-down, easy-open, self-closing, vented, user-lip operated conical gate, self-resealing gas-tight by carbonated content agitation, beverage can-end comprising, a top wall with an integral 360-degree downwardly and inwardly formed dual-fold seam (referred to as “triple-fold” in other patents) which defines the periphery of said conical gate opening, whereabout a 360-degree weakened line underneath thereon defines the circumferential portion of said conical gate, which, when said conical gate is pushed downwardly into the interior of the can, curls upwardly to form a rough severed circumferential edge of said conical gate, whose flange gets bent to a predisposed angle, that when returned to the smooth surface of said dual-fold seam forms a 360-degree gas vent between the mating areas of said rough circumferential edge of said conical gate and smooth surface of said dual-fold seam, with said conical gate attached to said can-end by a separate elastomeric component through a plurality of known fastening means, which together maintain alignment, and return said conical gate to said dual-fold seam into a self-closed, vented position within the opening of said dual-fold seam, and while in said self-closed vented position, the conical gate can be sequenced to a self-resealable gas-tight function by carbonated content agitation, which creates excessive gas flow that exceeds the gas flow limit of said self-closed venting, which causes increased internal pressure that forces the conical gate upwards against said dual-fold seam, causing said gate to circumferentially rotate upwardly and thus compress the inside circumference of the dual-fold seam against the shape-mated outside circumferential area of the conical gate creating a gas-tight seal. 
     Included herein is an example drawing of a thumb operated non-concentric lever-cam designed not to interfere with stacking, packaging, vending, or recycling. The advantage of the lever-cam over the pull-up stay-tab as used with this invention is that a 180-degree rotation of the lever-cam will fully open the aperture and hold it open which is suitable for conventional drinking or pouring. Rotating 180-degrees back to the original unopened position will allow the conical drink dome to automatically return to a gas venting anti-spill liquid sealed human lip operated gate configuration. 
     The artistic arrow symbol upwardly embossed into the top of the can end not only clues the first time consumer on which way to rotate the tab but the raised inside edge of the arrow provides one side of a detent that helps prevent the lever from being accidentally rotated and provides along the length of the arrow a ramp for the end of the lever-cam to leverage, against which should reduce the amount of material needed to manufacture the lever. The said lever-cam as used with a ramp is prior art U.S. Pat. No. 5,248,053 issued in 1993. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
         FIG. 1  is an exploded perspective view showing the improved can-end and resilient member (a spring). 
         FIG. 2  is a cross sectional left side view showing both open and closed aperture. 
         FIG. 3  is a perspective view of the invention attached to a can cylinder. 
         FIG. 4  is a cross-sectional left side close-up view of the triple-fold seal before the score line is broken. 
         FIG. 4   a  is a cross-sectional left side close-up view of the triple-fold seal with separated score line and resultant curled up flange of the conical drink dome. 
         FIG. 4   b  is a cross-sectional left side close-up view of the triple-fold seal with curved up separated score line reseated to create the limited gas vent. 
         FIG. 4   c  is a cross-sectional left side close-up view of the triple-fold seal responding to abnormal internal pressure and half way though transitioning to gas tight mode. 
         FIG. 4   d  is a cross-sectional left side close-up view of the triple-fold seal fully transitioned into gas tight mode. 
         FIG. 5  is a cross-sectional left side view showing the spring and seal before the score line is severed. 
         FIG. 5   a  is a cross-sectional left side view showing the spring and seal after the score line is severed, curled up, and reseated to form a gas vent. 
         FIG. 5   b  is a cross-sectional left side view showing the spring and conical drink dome in the open position. 
         FIG. 6  is a cross-sectional left side view of the invention from a drinking view before the score line is severed. 
         FIG. 6   a  is a cross-sectional left side view of the invention from a drinking perspective after the score line is severed and reseated to form a gas vent. 
         FIG. 6   b  is a cross-sectional left side view of the invention from a drinking perspective with conical drink dome in the open position. 
         FIG. 7  is a cross-sectional left side view of the invention showing a silhouette of lips before opening the gate. 
         FIG. 7   a  is a cross-sectional left side view of the invention showing a silhouette of lips having opened the gate. 
         FIG. 8  is a cross-sectional left side view of optional ramped lever cam not claimed in this invention and a claimed alternative more durable spring and a claimed alternative spring fastening method. 
         FIG. 8   a  is a cross-sectional left side view of optional ramped lever cam not claimed in this invention and a claimed alternative more durable spring and a claimed alternative spring fastening method. 
         FIG. 8   b  is a plan view of an optional ramped lever cam and embossed artistic arrow ramp not claimed in this invention. 
         FIG. 8   c  is a perspective view of said optional ramped lever cam and embossed artistic arrow ramp not claimed in this invention. 
         FIG. 9  is a cross-sectional left side close-up view of the distal portion of the seal. 
         FIG. 9   a  is also a cross-sectional left side close-up view of the distal seal area. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring more particularly to the drawings,  FIG. 1  illustrates a top exploded perspective view of an easy-open can-end  100  construction incorporating the principles of this invention. 
       FIG. 1  shows a can-end  100 , conical gate  200 , and resilient member  60 , prior to severance of the weakened line and prior to securing of the can-end to the top end of a generally cylindrical can body, such as by conventional double seaming, for example. Such can-end  100 , conical gate  200 , and resilient member  60  are generally made of any combination of sheet metal such as aluminum, steel or tinplate, but all may be made of nonmetallic or laminated material. 
     Also shown are formed portions on both the can-end and the conical gate, called the gate stake  22  and the can-end stake  24 , which serve to fasten the resilient member, through its gate stake hole  68  and its can-end stake hole  64 , respectively. The interior end  23  of the resilient member is shaped and sized so that it will impinge on the underside of the can-end and prevent the conical gate from swing laterally out of alignment with the opening of the can-end. 
     This view also presents a lever recess  23 , which is intended to locate the edge of a cam lever (not shown), a lip depression  26 , which positions the upper lip of the consumer, and the can-end seam  40 . This seam forms the opening of the beverage container, and is shown in greater detail in  FIG. 2 . 
       FIG. 2  illustrates a cross section side view of can-end  100  with combined closed and opened conical gate  200  views with resilient member  60  attached. Here the proximal portion of the seam  40  is shown with the distal seam portion  40 ′. The gate stake  22 , the can-end stake  24 , the lever recess  23 , the lip depression  26 , the gate stake hole  68 , and the can-end stake hole  64  can all be seen in cross-section. 
       FIG. 3  is a perspective view illustrating the can-end  100  assembled to a cylindrical can body without conventional leveraged tab or leveraged ramp-cam, which may be used if preferred. Here, the gate stake  22 , the can-end stake  24 , the lever recess  23  and the lip depression  26  can be seen in relation to the conical gate  200 , which is seated under the can-end seam  40 . 
       FIGS. 4 ,  4   a ,  4   b ,  4   c  and  4   d  illustrate in isolated cross sectional exploded views the sequences of the dual-fold multi-functional integral seam  40  formed into the stamped material blank of can-end  100 . These five views explain in detail the creation by severance of the 360-degree weakened line  42  the multiple functions of the multi-functional dual-fold seam  40 . 
     When the conical gate  200  circumferentially defined weakened line  42  in  FIG. 4  is severed from can-end  100  creating an independent but resiliently connected conical gate  200 , the gate flange  44  is curved upwardly while severing, as shown in  FIG. 4   a .  FIG. 4   b  shows the 360-degree rough severed edge  42   a  of conical gate  200  replaced against the dual-fold seam  40  smooth surface area  46  from which it was severed, in the self-closed vented position, and the dashed line arrow indicating carbonated gas flow  48  venting between the rough severed edge  42   a  and smooth surface area  46  which it is replaced against.  FIG. 4   c  shows excessive gas flow forcing the conical gate  200  upwardly  45  against the dual-fold seam  40  causing the gate flange  44  to bend and compress around its perimeter, reducing the clearance between the dual-fold seam  40  and the conical gate  200 , while also reducing the angle of the gate flange  44  relative to the smooth surface  46  of the dual-fold seam  40 , further reducing the gas flow of the venting function, which enhances the speed at which the self-sealing function is completed.  FIG. 4   d  illustrates the conical gate  200  as it is forced further upwards  45 , and dual-fold seam  40  rotating inwardly into contact with mating circumferential seal surface of the conical gate  200  to form the gas-tight seal  49 . 
       FIGS. 5 ,  5   a , and  5   b  illustrate a cross sectional side view of the can-end before the weakened line is severed, the weakened line is severed and the conical gate is returned, and the conical gate in the open position, respectively. Note that the newly exposed surface of gate flange now becomes gate mating surface  40   a . [In these views, when item numbers have a prime notation (′), it means that portion is the more distal of the two locations shown in the figure, for that single item] 
       FIGS. 6 ,  6   a , and  6   b  illustrate a cross section front view of the can-end before the weakened line is severed, the weakened line is severed and the conical gate is returned, and the conical gate in the open position, respectively. 
       FIGS. 7 and 7   a  illustrate a cross section side view of the can-end, after severing the weakened line, and being user-lip operated in closed, then opened position, respectively. 
       FIGS. 8 ,  8   a ,  8   b , and  8   c  show an alternative to the preferred embodiment push-down conical gate using a digitally operated rotational lever-cam and cam follower integral to the conical gate that facilitates pushing downwardly to first break the weakened line and then pushes outwardly and downwardly on the conical gate cam follower to complete the severing of the weakened line. The raised half-arrow around the circumferential perimeter of the can-end serves to reinforce and raise the digitally operated end of the lever-cam to enhance initial severing of the weakened score line and to illustrate to first time users the proper rotational direction of the lever-cam. 
       FIGS. 9 and 9   a  illustrate the can-end  100  and conical gate  200  contacting each other in an alternate embodiment of the invention. Here the can-end assembly is a multiple piece construction, where the gate  200  is a separate piece of material prior to assembly. In this case, the mating surfaces of the gate and the can-end are temporarily bonded together with an appropriate food-grade adhesive substance (not shown), such as corn syrup, or some other suitably-engineered chemical agent. In this alternate embodiment, the separate gate  200  operates the same way still, and reacts to gas pressure in a similar fashion.