Container closure
United States Patent [191 Wharton 1 CONTAINER CLOSURE [76] Inventor: Franklin Eugene Wharton, 1308 Sartori Ave., Torrance, Calif. 90501 [22] Filed: June 1, 1973 [21] Appl. No.: 366,258  
 [52] US. Cl. 215/358; 215/270; 215/364 [51] Int. Cl 865d 39/12 [58] Field of Searchmm. 215/48, 52. 231. 269. 270, 215/271, 301, 350, 361, 364&#39;, 220/245;  
 Primary Examiner-Herbert F. Ross Attorney, Agent, or FirmWilliam F. McDonald 1 1 Apr. s, 1975 [57] ABSTRACT A device for sealing an opening in a container which includes a hollow plug open at the top and having a solid bottom and walls shaped generally like the opening in the container. The hollow plug is adapted to fit within the opening. At least a portion of the walls of the plug are expansible outwardly within the opening and against the sides thereof. A reservoir is attached to the top of the plug in communication with the interior thereof. The entire plug-reservoir assembly is substantially airtight and contains a fluid. At least a portion of the wall of the reservoir is formed of bistable flexible material and is normally convex outwardly but adapted to assume a stable concave inwardly position. When this portion of the wall of the reservoir is in the stable concave inwardly position, this forces fluid from the reservoir into the plug so as to cause the expansible portion of the walls of the plug to expand outwardly within the opening ofthe container and against the sides thereof. whereby the opening in the container is sealed.  
 7 Claims, 7 Drawing Figures CONTAINER CLOSURE BACKGROUND OF THE INVENTION The present invention relates to closures for containers. It is particularly applicable to providing a substantially gas tight seal in a container such as a can or bottle.  
  Containers such as metal cans and glass bottles are widely used today for the containment of solids and liquids such as beverages. These containers are designed to protect their contents from contamination by the atmosphere. Further, with particular reference to liquids, the liquids are frequently carbonated or in some other manner contain gases under pressure. If the container is left open to the atmosphere for any length of time, the gases in the liquid will escape and the liquid will become what is known as flat.&#34; All of these problems are well known. Accordingly, there have been many attempts to provide various drvices for sealing the openings made in such containers. The degree of success of the closure has varied depending on the type of closure and the type of opening which it is adapted to close.  
  Many prior art closures, particularly of the plug type have been quite elaborate. The elaborateness or complexity of the closure was necessary in order to assure a satisfactory seal. At the same time, this frequently made the closure awkward to use and difficult to remove. Many of these prior art devices of necessity would rub against the sides of the opening as they were forced in and would be cut, abraded, and perhaps permanently deformed in the process. Thus, there has been a real need for a relatively simple plug type closure device which would seal the opening in a can or a bottle and be simple and easy to use and remove from the container and at the same time would be durable and capable of substantial reuse.  
 SUMMARY OF THE INVENTION It is an advantage ofthe present invention that it provides a closure for sealing an opening in a container such as a can or bottle which will effectively perform this function and provide a substantially pressure tight seal and at the same time be easy to apply and remove from the container. The closures are durable and capable of substantial reuse in that they do not have to be forced into the opening and thus are not likely to be cut, abraded, or permanently deformed.  
  The present invention provides a device or closure for sealing an opening in a container. The device includes a hollow plug open at the top and having a solid bottom and walls shaped generally like the opening and adapted to fit within the opening. At least a portion of the walls of the plug are expansible outwardly within the opening and against the sides thereof. A reservoir is attached to the top of the plug in communication with the interior thereof. The entire plug-reservoir assembly is substantially air tight and contains a fluid. At least a portion of the wall of the reservoir is formed of a bistable flexible material and is normally convex outwardly but is adapted to assume a stable concave inwardly position. When this portion of the wall is in a stable concave inwardly position, this forces fluid from the reservoir into the plug so as to cause the expansible portions of the walls of the plug to expand outwardly within the opening of the container and against the sides thereof. This seals the opening in the container.  
  Other objects and advantages of the present invention will be apparent from the following detailed description in conjunction with the accompanying drawings.  
 BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are illustrative of advantageous embodiments of this invention.  
 In the drawings:  
  FIG. I is a perspective view of a closure according to the present invention;  
  FIG. 2 is a perspective view of the embodiment of FIG. 1 showing it in sealing position on a container, a fragment only of the container being shown;  
  FIG. 3 is a side elevational view, in section, and with parts removed for purposes of clarity, showing the embodiment of position I in position on a container;  
  FIG. 4 is a side elevational view, in section, with parts removed for purposes of clarity, of the embodiment shown in FIG. 3 in sealing position in the container;  
  FIGJS is a side perspective view of another embodiment of the present invention;  
  FIG. 6 is a perspective view of the embodiment of FIG. 5, shown in sealing position in a container;  
  FIG. 7 is a perspective view of the embodiment shown in FIG. 5, illustrating another aspect of this invention.  
 DETAILED DESCRIPTION Throughout the drawings, corresponding reference numerals have been used for corresponding parts.  
  Referring now particularly to FIG. I, the closure device in accordance with the instant invention is indicated generally at 10. The device includes a hollow plug I2 FIG. 3) open at the top and having a solid bottom 14 and walls 16 shaped generally like the opening in the container to be sealed, and adapted to fit within the opening. At least a portion of walls 16 are expansible outwardly. This can be accomplished, for example, by making plug 12 of a flexible or resilient material such as rubber or a suitable synthetic plastic material. The walls 16 and bottom 14 of plug 12 can be of the same material, the expansibility being controlled by the relative thickness thereof.  
  A reservoir 18 is attached to the top of plug 12 in leak proof communication with the interior thereof, as shown in FIGS. I and 3. The entire plug l2-reservoir l8 assembly is substantially air tight and contains a suitable entrapped fluid such as a gas, e.g. air. At least a portion 20 of the wall 22 of reservoir 18 is formed of a bistable flexible material normally convex outwardly as shown in FIGS. 1 and 3. However, referring now to FIGS. 2 and 4, the bistable portion 20 is flexed inwardly to assume a stable concave inwardly position as shown therein. When this is done with the plug 12 within the opening 24 of a container 26 (shown here as a can), fluid is forced from reservoir 18 into plug 12. This causes the expansible portions of walls I6 to expand outwardly under fluid pressure within opening 24 of container 26 and against the sides of the opening. This effectively seals the opening in the container as can readily be seen.  
  Any suitable materials of construction can be used for both the reservoir 18 and the plug 12 portions of closure 10. They can, for example, both be made of rubber with the different properties resulting from control of the thickness of the various wall portions. Alternatively, they can be of different materials to precisely tailor the qualities of closure 10 for the particular sealing application. In all events, the principle of operation is the same.  
  As can be seen in the figures, the reservoir 18 is desirably larger than the opening 24 in container 26. This prevents closure 10 from falling into the container when not in the sealing position and further helps to po sition closure 10 for proper sealing. The positioning and sealing may be further enhanced by the provision ofa seat 28 formed in the surface of wall 22 of reservoir 18. This seat 28 is adapted to rest against the top of opening 24 and container 26 when plug 12 is inserted therein.  
  Suitable means such as knob 30 may be attached to reservoir 18 as shown for moving the bistable flexible portion 20 of wall 22 between the concave and convex positions. It should be appreciated that in many instances this will not be necessary and finger pressure first on the top and then on the sides of the reservoir can be used to accomplish this result. This is analogous to squeezing a hollow rubber ball until it develops a permanent dimple and then squeezing it in a different portion to release the dimple.  
  Referring now to FIGS. and 6, another embodiment ofthe invention is shown, which is particulary applicable to sealing bottles.  
  Since this embodiment of closure is particularly adapted to seal an opening 24 in a container 26 which is a bottle, the plug 12 portion ofclosure 10 is of generally cylindrical shape to fit the opening 24. Desirably, as shown, portions 32 of wall lb of plug 12 are thicker than the remainder of wall 16, thick to a point of being substantially non-expansible. Thick portions 32 help retain the desired shape ofplug l2 and facilitate the insertion thereof into opening 24 in neck 34. When this is done. as shown in FIG. 6, the bistable portion of wall 22 of reservoir 18 is pushed into its stable concave inwardly position, which forces fluid from reservoir 18 into plug 12 so as to cause the expansible portions of wall 16 to expand outwardly within opening 24 and against the sides thereof along neck 34). This effectively seals the opening 24.  
  With particular reference to the embodiments of the present invention useful in sealing openings in glass containers such as bottles. it may be desirable to provide some means for preventing too great a pressure from being exerted against the sides of the opening in the glass walled container which could cause the container to shatter. A suitable way of preventing this occurrence is shown in FIG. 7. Bottom 14 of plug 12 may be made, for example, through control of thickness or material properties, to be normally non-expansible. but at the same time adapted to expand if the pressure within plug 12 reaches a predetermined level. Bottom 14 in expanded position is shown in FIG. 7. This expan sion of bottom 14 will prevent further pressure build up within plug 12 and thus prevent walls 16 from exerting a force against the sides of opening 24, for example, neck 34. greater than can be withstood by container 26.  
  The illustrative embodiments indicate several of the advantages of the instant invention. Since closure 10 can be made of essentially one material, for example, rubber, the dimensions thereof being controlled to impart the desired properties to the various parts thereof, it may be substantially inert to the contents of the container. Further it is easily inserted into the container, provides an effective pressure tight seal and at the same time is easily removed therefrom. It can, of course, be reused substantially indefinitely. It does not have to be forced or wedged into the opening to create a seal and thus there is little cutting, abrading, or permanent deforming of the closure.  
  There have been shown and described hereinabove possible embodiments of this invention and it is to be understood that the invention is not limited thereto, and that various changes, alterations, and modifications can be made thereto without departing from the spirit and scope thereof as defined in the claims wherein what is claimed is:  
  l. A device for sealing an opening in a container which comprises:  
 a. a hollow plug open at the top and having a solid bottom and walls shaped generally like the opening and adapted to fit within the opening, at least a portion of the walls of the plug being expansible out wardly within the opening and against the sides thereof;  
 b. a reservoir attached in leak proof relationship to the top of the plug in communication with the interior thereof, the entire plug-reservoir assembly being substantially air tight and containing an entrapped fluid, at least a portion of the wall of the reservoir being formed of a bistable flexible material normally convex outwardly but flexed inwardly to assume a stable concave position which forces the entrapped fluid from the reservoir into the plug so as to cause the expansible portion of the walls of the plug to expand outwardly under fluid pressure within the opening of the container and against the sides thereof, whereby the opening in the container is sealed.  
 2. The device of claim 1 wherein the reservoir is larger than the opening in the container.  
  3. The device of claim 2 including a seat formed in the surface of the reservoir and adapted to rest against the top of the opening in the container when the plug is inserted therein.  
  4. The device of claim 1 including means attached to the reservoir for moving the bistable flexible portion of the wall thereof between the convex and concave positions.  
  5. The device of claim 1 wherein the solid bottom is normally non-expansible but is adapted to expand if the pressure within the plug reaches a predetermined level so as to prevent the walls of the plug from exerting a force against the sides of the opening greater than the container can stand.  
 6. The device of claim 1 wherein the fluid is a gas.  
 7. The device of claim 6 wherein the gas is air.  
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