Headspace modification method for removal of vacuum pressure and apparatus therefor

Abstract

To modify the headspace in a container to remove vacuum pressure, a container has a seal or cap which may provide a temporary opening into the container which is sealable under compression to provide a controlled raising of the internal pressure as the heated contents of the container cools. A sealing chamber ( 84 ) may enable the introduction of a fluid into the headspace ( 23 b ) to force the fluid level ( 40 ) lower. Other methods and apparatus are described.

1 . An apparatus for pressurizing a headspace of a filled plastic bottle while applying a cap, comprising:
 a pressure chamber having a sealing ring for engaging a surface on the plastic bottle;   an apparatus for positioning the sealing ring engagement with the surface on the plastic bottle;   holding apparatus for holding the cap in position to engage a finish of the plastic bottle;   the pressure chamber surrounding the holding apparatus and connected to the sealing ring;   a source of pressure coupled to the pressure chamber for introducing a volume of gas or vapor into the chamber; and   an apparatus for moving the holding apparatus and the cap within the pressure chamber while the pressure chamber is subjected to the volume of gas or vapor to seal the gas or vapor within the headspace of the filled plastic bottle with the cap.   
     
     
         2 . The apparatus of  claim 1 , wherein the sealing ring includes a surface configured to engage an outer surface of a support ring on the plastic bottle. 
     
     
         3 . The apparatus of  claim 2 , wherein the sealing ring includes an upwardly facing surface and the pressure chamber includes a downwardly facing sealing surface for contacting the upwardly facing surface of the sealing ring. 
     
     
         4 . The apparatus of  claim 1 , wherein the apparatus for moving the holding apparatus comprises an apparatus for rotating the holding apparatus and an apparatus for moving the holding apparatus vertically within the pressure chamber. 
     
     
         5 . The apparatus of  claim 1 , wherein the source of pressure comprises a source of pressurized air. 
     
     
         6 . The apparatus of  claim 1 , further comprising apparatus for moving the sealing ring and bottle relative to each other at least when the sealing ring is not engaging a surface on the bottle. 
     
     
         7 . The apparatus of  claim 1 , wherein the pressure chamber comprises a downwardly inclined peripheral wall including a downwardly facing sealing surface on a lower perimeter thereof, and an upper end wall closing the peripheral wall. 
     
     
         8 . The apparatus of  claim 7 , further comprising a central opening in the upper end wall including a seal surrounding a stem extending through the central opening and coupling the holding apparatus to the apparatus for rotating the holding apparatus. 
     
     
         9 . The apparatus of  claim 7 , wherein the downwardly inclined peripheral wall portion is connected to a lower end wall portion and the sealing ring is provided within the lower end wall portion. 
     
     
         10 . The apparatus of  claim 1 , wherein the pressure chamber comprises at least two connecting portions. 
     
     
         11 . The apparatus of  claim 1 , wherein the pressure chamber comprises more than 2 connecting portions. 
     
     
         12 . The apparatus of  claim 1 , wherein the sealing ring includes a surface configured to engage a lower surface of a support ring on the plastic bottle. 
     
     
         13 . A method for applying a cap to a finish of a filled plastic bottle comprising the steps of:
 positioning a chamber containing an apparatus holding a cap over the finish of the bottle so that a lower edge of the chamber is connected to a sealing ring;   pressing the sealing ring to a surface of known dimension on the bottle;   pressurizing the chamber and bottle interior with a volume of gas or vapor;   moving the holding apparatus and cap within the chamber relative to the finish of the bottle to seal the gas or vapor within the bottle;   releasing the pressure within the chamber; and   removing the sealing ring from the surface of known dimension.   
     
     
         14 . The method of  claim 13 , wherein the pressing step comprises engaging an outer surface of a support ring on the bottle with the sealing ring having an inner surface. 
     
     
         15 . The method of  claim 13 , wherein the step of moving the holding apparatus and cap comprises rotating the holding apparatus and cap while moving the holding apparatus and cap downward relative to the chamber. 
     
     
         16 . The method of  claim 13 , wherein the step of removing the sealing ring is preceded by releasing the cap from the holding apparatus. 
     
     
         17 . The method of  claim 13 , wherein the step of removing the sealing ring is followed by moving at least one of the sealing ring and bottle relative to each other by a distance sufficient to position the sealing ring on a second bottle and supplying a second cap to he applied to the second bottle to the holding apparatus. 
     
     
         18 . A system for pressure capping bottles comprising:
 apparatus for supplying a bottle filled with a liquid to a desired fill point, the bottle having a finish suitable to engage a cap and a surface;   a sealing ring having a surface for engaging the surface of the bottle;   an apparatus for moving the sealing ring from a position spaced from the bottle to a position engaging the surface of the bottle;   a source of caps for supplying a holding apparatus with a cap, the holding apparatus being adapted to hold a cap in a position to engage a finish of the bottle;   a pressure chamber surrounding the holding apparatus engaging the sealing ring;   a source of pressure coupled to the pressure chamber for introducing a sufficient volume of gas or vapor to the chamber to pressurize the headspace within the bottle above the fill point to a desired pressure; and   apparatus for moving the holding apparatus and cap within the pressure chamber while the chamber is subjected to the gas or vapor to seal the gas or vapor within the headspace of the bottle with the cap.   
     
     
         19 . The system of  claim 18 , wherein the pressure chamber comprises a peripheral wall including the sealing surface on a lower perimeter thereof for sealing engagement with a surface of the sealing ring, an upper end wall closing the peripheral wall, a central opening in the upper end wall including a seal surrounding a stem coupled to the holding apparatus and extending through the central opening and an apparatus for rotating the holding apparatus relative to the pressure chamber. 
     
     
         20 . The system of  claim 18 , further comprising apparatus for vertically reciprocally moving the holding apparatus and sealing ring in relation to the apparatus for supplying a bottle so that the bottle is capped while containing a sufficient volume of gas or vapor in the headspace within the bottle to a desired pressure. 
     
     
         21 . The apparatus of  claim 1 , wherein the pressure chamber comprises at least two parts.