Preform assembly, container assembly, and method of manufacture

Abstract

A method of making a preform assembly including providing a finish ring of plastic construction, placing the finish ring onto a core pin, introducing a preform polymer into a mold cavity that includes the core pin, and compression molding the preform polymer to the finish ring. A resulting preform assembly, and container assembly blow-molded from the preform assembly, are also disclosed.

1 . A method of making a preform assembly, said method including: 
 (a) providing a finish ring of plastic construction,    (b) placing said finish ring onto a core pin,    (c) introducing a preform polymer into a mold cavity,    (d) placing said core pin and finish ring into said mold cavity around said core pin, and    (e) compression molding said preform polymer to said finish ring.    
     
     
         2 . The method of  claim 1  wherein said step (a) includes providing said finish ring with an internal surface having at least one radial interengagement feature, such that a portion of said preform polymer flows during said step (e) into interengagement with said at least one radial interengagement feature during said compression molding step.  
     
     
         3 . The method of  claim 2  wherein said step (a) includes said at least one radial interengagement feature being at least one radial recess, such that a portion of said preform polymer flows into said at least one radial recess during said compression molding step.  
     
     
         4 . The method of  claim 3  wherein said step (a) also includes said at least one radial recess being at least one annular groove, such that a portion of said preform polymer flows into said at least one annular groove during said compression molding step.  
     
     
         5 . The method of  claim 1  wherein said step (a) includes providing said finish ring with an internal surface having at least a portion thereof greater in diameter than said core pin, such that a gap is formed during said step (e) between said at least a portion of said internal surface, said core pin, and a forward edge of said preform polymer, said gap being provided to accommodate within-tolerance variation of a molten charge of said preform polymer to prevent overpacking of said preform polymer into said finish ring.  
     
     
         6 . A preform assembly produced by the method of  claim 5 .  
     
     
         7 . A preform assembly produced by the method of  claim 1 .  
     
     
         8 . A method of making a container assembly includes blow molding the preform assembly of  claim 7 .  
     
     
         9 . A container assembly produced by the method of  claim 8 .  
     
     
         10 . A preform assembly for blow molding a container assembly, which includes: 
 a molded plastic finish ring, and    a plastic preform compression molded to said finish ring such that a neck portion of said plastic preform radially interengages said finish ring.    
     
     
         11 . The preform assembly set forth in  claim 10  wherein said finish ring includes at least one internal surface with at least one radial interengagement feature formed therein, further wherein said neck portion of said plastic preform radially interengages with said at least one radial interengagement feature.  
     
     
         12 . The preform assembly set forth in  claim 10  wherein said finish ring includes at least one tapered internal surface, at least one straight internal surface, and a transition point therebetween, and wherein there is an open gap between said transition point and a forward edge of said neck portion of said plastic preform to prevent said neck portion of said plastic preform from being overpacked into said finish ring.  
     
     
         13 . A container assembly blow molded from a preform assembly produced from compression molding a preform to a molded plastic finish ring, said container assembly includes: 
 said molded plastic finish ring, and    a plastic container having a neck portion thereof interengaging said finish ring.    
     
     
         14 . The container assembly set forth in  claim 13  wherein said finish ring includes at least one internal surface with at least one radial interengagement feature formed therein, and wherein said neck portion of said plastic container interengages with said at least one radial interengagement feature.  
     
     
         15 . The container assembly set forth in  claim 14  wherein said finish ring includes at least one tapered internal surface, at least one straight internal surface, and a transition point therebetween, and wherein a gap is defined between said transition point and a forward edge of said neck portion of said plastic container to prevent said neck portion of said plastic container from being overpacked into said finish ring.