Sealing Grommet And Method Of Filling

Abstract

The grommet used for sealing the charging opening in a pressurized dispensing container is designed so that it can be held in a venting state prior to the charging of the propellant chamber. The design involves an annular ridge above the neck of the grommet and an annular groove above the annular ridge. In that fashion, the grommet can be held loosely on the opening in the base of the container. Flats or cutaways on the crown and groove assure passageway between the propellant chamber and the outside so that air can be taken in and expelled from the propellant chamber during the product loading stages.

1 . In a pressurized dispensing container, a grommet for sealing the opening through which a propellant charge is injected into the container, wherein the grommet has a crown, a base and a resilient stretchable neck between the crown and the base to permit the grommet to be in a sealed state when the neck is in a first extended position and to permit pressurized fluid to be charged into the base of a container through the grommet when the neck is in a second, more extended, position, the improvement comprising:
 an annular ridge above the neck   an annular groove above said annular ridge and below the crown,   the crown having a maximum diameter greater than the diameter of the charging opening of the container   said annular groove dimensioned to fit within the charging opening of the container in a non-sealing state for the grommet, and   at least one longitudinally extending venting channel along the crown so that when the grommet is in said non-sealing state air can enter and exit from the container through said venting channel during the filling stages of the container,   said annular groove together with said venting channel positioned within the container in the sealed state of the grommet.   
     
     
         2 . The grommet improvement of  claim 1  wherein: said venting channel is partially defined by a flat, said flat being on the surfaces of the crown and said groove. 
     
     
         3 . The grommet improvement of  claim 1  wherein: there are four of said venting channels. 
     
     
         4 . The grommet improvement of  claim 2  wherein: there are four of said flats creating four of said channels. 
     
     
         5 . The grommet improvement of  claim 4  wherein: said four flats encompass approximately 50 percent of the circumference of the crown. 
     
     
         6 . The method of preparing a pressurized dispensing container containing a piston with product to be dispensed from a product chamber on the top of the piston and with propellant in a propellant chamber under the piston, comprising the steps of:
 holding a grommet in the charging opening at the base of the container in a first position that provides a venting of air in and out of the propellant chamber through a venting channel, said venting channel at least partially defined by the grommet,   loading product to be dispensed into the product chamber,   pushing product and piston into a fully downward position to minimize air between product and piston and thus venting gas through the venting channel,   then applying gas under pressure through the venting channel to force the piston up and thereby minimize air at the top of the product in the product chamber,   moving the grommet to a second position to provide a seal, and   charging the propellant chamber with propellant through a charging channel in the grommet to provide pressurized product in the product chamber.   
     
     
         7 . The method of  claim 6  wherein: said step of pushing occurs simultaneous with said step of loading. 
     
     
         8 . The method of  claim 6  wherein: said step of pushing occurs after said step of loading. 
     
     
         9 . The method of preparing a pressurized dispensing container containing a piston with product to be dispensed from a product chamber on the top of the piston and with propellant in a propellant chamber under the piston, comprising the steps of:
 inserting a grommet into a charging opening in the base of the container to a first position that provides a venting of air in the propellant chamber through a venting channel, said venting channel at least partially defined by the grommet,   loading product to be dispensed into the product chamber,   then applying gas under pressure into the product chamber thereby pushing product and piston into a fully downward position to minimize air between product and piston and thus venting gas through the venting channel,   then applying gas under pressure through the venting channel to push the piston up and thereby minimize air at the top of the product in the product chamber,   moving the grommet to a second position to provide a seal, and   charging the propellant chamber with propellant through a charging channel in the grommet to provide pressurized product in the product chamber.   
     
     
         10 . The method of preparing a pressurized dispensing container containing a barrier element with product to be dispensed from a product chamber on a first side of the barrier element and with propellant in a propellant chamber on a second side of the barrier, comprising the steps of:
 inserting a grommet into a charging opening in the base of the container to a first position that provides a venting of air in the propellant chamber through a venting channel, said venting channel at least partially defined by the grommet,   loading product to be dispensed into the product chamber thereby expanding the product chamber, reducing the volume of the propellant chamber and venting air from the propellant chamber, through the venting channel of the grommet as the propellant chamber decreases in volume,   moving the grommet to a second position to provide a seal, and   charging the propellant chamber with propellant through a charging channel in the grommet to provide pressurized product in the product chamber.