Pressurized capping apparatus

Abstract

Apparatus for pressurizing the headspace of a filled plastic bottle while applying a cap includes a sealing ring having a surface for engaging a support ring, or other surface of known dimension, of the plastic bottle, clamping apparatus for moving the sealing ring, a chuck for holding the cap in a position to engage a finish of the plastic bottle, a pressure chamber surrounding the chuck having a sealing surface for contacting the sealing ring, a source of pressure coupled to the pressure chamber for introducing a volume of gas or vapor at super-atmospheric pressure into the chamber, and a motor for rotating the chuck and cap within the pressure chamber while the chamber is subjected to the gas or vapor at super-atmospheric pressure to seal the gas or vapor within the headspace of the filled plastic bottle with the cap.

1 . Apparatus for pressurizing the headspace of a filled plastic bottle while applying a cap comprising:
 a sealing ring having a first surface for engaging a surface of known dimension on the plastic bottle, and a second surface,   clamping apparatus for moving the sealing ring from a position spaced from the surface of known dimension to a position engaging the surface of known dimension,   a chuck for holding a cap in a position to engage a finish of the plastic bottle,   a pressure chamber surrounding the chuck having a sealing surface for contacting the sealing ring second surface,   a source of pressure coupled to the pressure chamber for introducing a volume of gas or vapor at super-atmospheric pressure into the chamber, and   apparatus for moving the chuck and cap within the pressure chamber while the chamber is subjected to the gas or vapor at super-atmospheric pressure 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 first surface comprising a concave radial inner surface for engaging a radial outer surface of a support ring on the plastic bottle. 
     
     
         3 . The apparatus of  claim 1 , wherein the sealing ring second surface is an upwardly facing planar surface and the pressure chamber sealing surface is a downwardly facing surface including a circumferential seal for contacting the sealing ring second surface. 
     
     
         4 . The apparatus of  claim 1 , wherein the apparatus for moving the chuck and cap comprises a motor coupled to the chuck for rotating the chuck and cap and apparatus for moving the chuck and cap vertically within the pressure chamber. 
     
     
         5 . The apparatus of  claim 1 , wherein the source of pressurized gas or vapor comprises a source of pressurized air, nitrogen or CO 2 . 
     
     
         6 . The apparatus of  claim 1 , further comprising apparatus for longitudinally moving the pressure chamber and clamping ring toward and away from each other. 
     
     
         7 . The apparatus of  claim 6 , further comprising a source of caps for supplying the chuck, and wherein the apparatus for longitudinally moving the pressure chamber and clamping ring includes a range of movement sufficient to permit a cap from the source of caps to be inserted into the chuck. 
     
     
         8 . The apparatus of  claim 1 , further comprising apparatus for moving the clamping ring and bottle relative to each other at least when the clamping ring is in the position spaced from the support ring. 
     
     
         9 . The apparatus of  claim 4 , wherein the pressure chamber comprises a peripheral wall including the sealing surface on a lower perimeter thereof, and an upper end wall closing the peripheral wall. 
     
     
         10 . The apparatus of  claim 9 , further comprising a central opening in the upper end wall including a seal surrounding a stem extending through the central opening and coupling the chuck to the motor. 
     
     
         11 . A method for applying a cap to a finish of a filled plastic bottle comprising:
 clamping a ring to a surface of known dimension on the bottle,   positioning a chamber containing a chuck holding a cap over the finish of the bottle so that a lower edge of the chamber seals against the clamped ring,   pressurizing the chamber and bottle interior with a volume of gas or vapor at a super atmospheric pressure,   moving the chuck and cap within the chamber relative to the finish of the bottle to seal the gas or vapor within the bottle at the super atmospheric pressure,   releasing the pressure within the pressure chamber, and   unclamping the ring from the surface of known dimension.   
     
     
         12 . The method of  claim 11 , wherein the clamping step comprises engaging a radial outer surface of a support ring on the bottle with a sealing ring having a concave radial inner surface. 
     
     
         13 . The method of  claim 11 , wherein the positioning step comprises vertically moving one of the clamping ring and chamber in relation to the other. 
     
     
         14 . The method of  claim 11 , wherein the moving step comprises rotating the chuck and cap while moving the chuck and cap downward relative to the chamber. 
     
     
         15 . The method of  claim 11 , wherein the unclamping step is preceded by releasing the cap from the chuck. 
     
     
         16 . The method of  claim 11 , wherein the unclamping step is followed by moving at least one of the clamping ring and bottle relative to each other by a distance sufficient to position the clamping ring around a second bottle. 
     
     
         17 . The method of  claim 16 , further comprising the step of supplying a second cap to the chuck to be applied to the second bottle. 
     
     
         18 . A system for pressure capping bottles comprising:
 apparatus for supplying a series of bottles filled with a liquid to a desired fill point, each of the bottles having a finish suitable to engage a cap and a surface situated below the finish of uniform known dimension,   a sealing ring having a first surface for engaging the surface of known dimension on the bottle, and a second surface, and clamping apparatus for moving the sealing ring from a position spaced from the series of bottles to a position engaging the surface of known dimension on a first of the series of bottles,   a source of caps for supplying a chuck with a series of caps, the chuck being adapted to hold a cap in a position to engage a finish of one of the bottles, and a pressure chamber surrounding the chuck having a sealing surface for contacting the sealing ring second surface,   a source of pressure coupled to the pressure chamber for introducing a sufficient volume of gas or vapor at super-atmospheric pressure into the chamber to pressurize the headspace within the bottle above the fill point to a desired pressure, and   apparatus for moving the chuck and cap within the pressure chamber while the chamber is subjected to the gas or vapor at super-atmospheric pressure 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 an upper 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 chuck and extending through the central opening, and a motor for rotating the chuck relative to the pressure chamber. 
     
     
         20 . The system of  claim 18 , further comprising apparatus for vertically reciprocally moving the chuck and sealing ring in relation to the apparatus for supplying the series of bottles so that each bottle in the series is capped while containing a sufficient volume of gas or vapor at super-atmospheric pressure in the headspace within the bottle to a desired pressure.