Dual seal closure and package

Abstract

A closure for sealing engagement with a container neck finish having at least one external thread segment includes a base wall having a skirt with at least one internal thread segment for engagement with the at least one external thread segment to thread the closure onto the container neck finish. A first flexible resilient annular wall extends from the base wall within the skirt and is positioned for sealing engagement with an inside surface of the container neck finish when the closure is threaded onto the neck finish. A second flexible resilient annular wall extends from the base wall between the first annular wall and the skirt, and is positioned for sealing engagement with an outside surface of the container neck finish when the closure is threaded onto the container neck finish. A circumferential series of external first axial ribs are on the first annular wall and a circumferential series of internal second axial ribs are on the second annular wall. The first and second series of ribs angularly alternate around the first and second annular walls, and function both to stiffen the first and second annular walls and to limit penetration of the container neck finish between the first and second annular walls.

1 . A closure for sealing engagement with a container neck finish having at least one external thread segment, which includes:
 a base wall having a skirt with at least one internal thread segment for engagement with the at least one external thread segment to thread the closure onto the container neck finish,   a first flexible resilient annular wall extending from said base wall within said skirt and positioned for sealing engagement with an inside surface of the container neck finish when the closure is threaded onto the container neck finish,   a second flexible resilient annular wall extending from said base wall between said first annular wall and said skirt and positioned for sealing engagement with an outside surface of the container neck finish when the closure is threaded onto the container neck finish, and   a circumferential series of external first axial ribs on said first annular wall and a circumferential series of internal second axial ribs on said second annular wall, said first and second series of axial ribs angularly alternating around said first and second annular walls and functioning both to stiffen said first and second annular walls and to limit penetration of the container neck finish between said first and second annular walls.   
   
   
       2 . The closure set forth in  claim 1  including an annular internal shoulder on said skirt adjacent to said base wall to limit outward flexure of said second annular wall. 
   
   
       3 . The closure set forth in  claim 2  wherein said annular internal shoulder has a convex radially inwardly facing surface opposed to said second annular wall. 
   
   
       4 . The closure set forth in  claim 1  wherein said first annular wall has a radially outwardly facing surface with a convex annular bead positioned for sealing engagement with the inside surface of the container neck finish when the closure is threaded onto the container neck finish. 
   
   
       5 . The closure set forth in  claim 1  wherein said first annular wall has a conical radially inwardly facing surface positioned for sealing engagement with the container neck finish when said closure is threaded onto the container neck finish. 
   
   
       6 . The closure set forth in  claim 1  wherein said first and second axial ribs have radial dimensions such that said ribs overlap each other circumferentially between said annular walls. 
   
   
       7 . A closure for sealing engagement with a container neck finish having at least one external thread segment, which includes:
 a base wall having a skirt with at least one internal thread segment for engagement with the at least one external thread segment to thread said closure onto the container neck finish,   a first flexible resilient annular wall extending from said base wall within said skirt and positioned for sealing engagement with an inside surface of the container neck finish when the closure is threaded onto the container neck finish,   a second flexible resilient annular wall extending from said base wall between said first annular wall and said skirt and positioned for sealing engagement with an outside surface of the container neck finish when the closure is threaded onto the container neck finish, and   an annular shoulder on said skirt adjacent to said base wall with a convex radially inwardly facing surface opposed to said second annular wall and positioned for engagement by said second annular wall when said closure is threaded onto the container neck finish and said neck finish is received between said annular walls for holding said second annular wall in sealing engagement with the outside surface of the container neck finish.   
   
   
       8 . The closure set forth in  claim 7  including a circumferential series of external first axial ribs on said first annular wall and a circumferential series of internal second axial ribs on said second annular wall, said first and second series of axial ribs angularly alternating around said first and second annular walls and functioning both to stiffen said first and second annular walls and to limit penetration of the container neck finish between said first and second annular walls. 
   
   
       9 . The closure set forth in  claim 7  including a circumferential series of radial ribs extending along said base wall between said first and second annular walls and positioned for engagement by a container neck finish received between said first and second annular walls to limit penetration of the neck finish between said walls. 
   
   
       10 . The closure set forth in  claim 7  including an annular shoulder on said base wall extending radially between said first and second annular walls for engagement by a container neck finish received between said annular walls to limit penetration of the neck finish between said walls. 
   
   
       11 . The closure set forth in  claim 7  wherein said first annular wall has a radially outwardly facing surface with a convex annular bead positioned for sealing engagement with the inside surface of the container neck finish when the closure is threaded onto the container neck finish. 
   
   
       12 . The closure set forth in  claim 7  wherein said first annular wall has a conical radially outwardly facing surface positioned for sealing engagement with the inside surface of the container neck finish when said closure is threaded onto the container neck finish. 
   
   
       13 . A package that includes a container having a neck finish with at least one external thread segment and a closure threaded onto said neck finish, said closure including:
 a base wall having a skirt with at least one internal thread segment engaged with said at least one external thread segment on said neck finish,   a first annular wall extending from said base wall within said skirt in sealing engagement with an inside surface of said neck finish,   a second annular wall extending from said base wall between said first annular wall and said skirt in sealing engagement with an outside surface of said neck finish, and   a circumferential series of external first axial ribs on said first annular wall and a circumferential series of internal second axial ribs on said second annular wall, ribs of said first series being angularly disposed between ribs of said second series around said axial walls, said neck finish being engaged by said ribs such that said ribs limit penetration of said neck finish between said first and second annular walls.   
   
   
       14 . The package set forth in  claim 13  including an annular internal shoulder on said skirt adjacent to said base wall and having a convex radially inwardly facing surface engaged by said second annular wall to hold said second annular wall in sealing engagement with said outside surface of said neck finish. 
   
   
       15 . The package set forth in  claim 13  wherein said first annular wall has a radially outwardly facing surface with a convex annular bead in sealing engagement with said inside surface, of said neck finish. 
   
   
       16 . The package set forth in  claim 13  wherein said first and second series of ribs have radial dimensions such that said ribs overlap each other circumferentially between said walls. 
   
   
       17 . A package that includes a container having a neck finish with at least one external thread segment and a closure threaded onto said neck finish, said closure including:
 a base wall having a skirt with at least one internal thread segment engaged with said at least one external thread segment on said neck finish,   a first annular wall extending from said base wall within said skirt in sealing engagement with an inside surface of said container neck finish,   a second annular wall extending from said base wall between said first annular wall and said skirt in sealing engagement with an outside surface of said neck finish, and   an annular shoulder on said skirt adjacent to said base wall with a convex radially inwardly facing surface engaged by said second annular wall and holding said second annular wall in sealing engagement with said outside surface of said neck finish.   
   
   
       18 . The package set forth in  claim 17  wherein said closure includes a circumferential series of external first axial ribs on said first axial wall and a circumferential series of internal second axial ribs on said second annular wall, with ribs of said first series angularly alternating with ribs of said second series, said ribs being engaged by said neck finish and limiting penetration of said neck finish between said first and second annular walls. 
   
   
       19 . The package set forth in  claim 17  wherein said closure includes a circumferential series of radial ribs extending along said base wall between said first and second annular walls, said ribs being engaged by said container neck finish and limiting penetration of said container neck finish between said first and second annular walls. 
   
   
       20 . The package set forth in  claim 17  wherein said closure includes an annular shoulder on said base wall extending between said first and second annular walls and engaged by said neck finish to limit penetration of said neck finish between said first and second annular walls. 
   
   
       21 . The package set forth in  claim 17  wherein said first annular wall on said closure has a radially outwardly facing surface with a convex annular bead in sealing engagement with said inside surface of said neck finish.