Tamper evident bottle cap

Abstract

A closure for sealing the opening of a container. The closure may include an angled plug. The container includes an external thread configuration and the closure includes an internal thread configuration which are adapted to pass over each other with one of the external and internal thread configurations having at least one thread lead and the other having at least twice as many thread leads. The closure includes an inwardly turned retaining rim extends at least partially upwardly. The retaining rim has an attachment boss and an upwardly extending line of weakness adjacent the attachment boss such that when the closure is removed from the container, the line of weakness tears allowing the tamper-evidencing band to remain with the closure upon removal from the container. The closure may include a top having a periphery, an annular skirt depending downwardly from the periphery and including a lower edge and a line of weakness extending upwardly from the lower edge, a tear tab extending downwardly from the skirt below the lower edge, and a tamper-evidencing locking member including an inwardly extending locking ring that extends radially inwardly from the skirt intermediate the top and the bottom edge, the retaining rim including a free edge that is adapted to engage the radially extending locking bead of the container when the closure is removed from the container neck. A method of molding a closure including a tamper-evidencing band is also disclosed.

1 . A closure for sealing the opening of a container having a threaded neck, said closure comprising:
 a top having an underside;   a downwardly depending annular skirt;   a thread configuration on an inner surface of said skirt; and   a plug extending downwardly and outwardly from said underside of said top, said plug including an upper end joined to said underside and having an upper outer diameter, said plug further including a lower portion spaced from said upper portion and having a lower outer diameter larger than said upper outer diameter.   
     
     
         2 . The closure of  claim 1 , wherein said lower portion includes a maximum outer diameter of said plug forming a sealing surface adapted to seal the container opening. 
     
     
         3 . The closure of  claim 1 , wherein said annular skirt comprises a lower skirt wall portion having a first inner diameter and an upper skirt wall portion proximal said top, said upper skirt wall portion having a second inner diameter larger than said first inner diameter. 
     
     
         4 . A combination comprising:
 a container including a neck forming an opening;   a closure for sealing said opening, said closure including a downwardly depending skirt;   an external thread configuration on an outer surface of said neck; and   an internal thread configuration on an inner surface of said skirt shaped to mate with said external thread configuration on said neck;   said external and internal thread configurations being adapted to pass over each other upon downward movement of said closure skirt relative to said container neck, wherein one of said external and internal thread configurations have at least one thread lead and the other of said external and internal thread configurations have at least twice as many thread leads as said one thread configuration.   
     
     
         5 . The combination of  claim 4 , wherein said external thread configuration includes four thread leads and said internal thread configuration includes eight thread leads. 
     
     
         6 . A tamper-evidencing closure for sealing a container, said closure comprising:
 a top, a depending annular skirt and a tamper-evidencing band frangibly connected to said annular skirt;   said tamper-evidencing band including an inwardly turned retaining rim that extends at least partially upwardly, said retaining rim having a free edge adapted for engagement with a locking surface of the container; and   said tamper-evidencing band including an attachment boss and an upwardly extending line of weakness adjacent said attachment boss such that when said closure is removed from the container, said line of weakness tears allowing said tamper-evidencing band to remain connected to said closure upon removal from said container.   
     
     
         7 . The closure of  claim 6 , wherein said retaining rim includes terminal ends forming a gap in said retaining rim aligned with said line of weakness. 
     
     
         8 . The closure of  claim 6 , wherein said tamper-evidencing band includes a tapered annular band wall having an upper portion and a lower portion, said upper portion being thinner than said lower portion. 
     
     
         9 . The closure of  claim 8 , wherein said upper portion forms a sharp corner for facilitating demolding of said closure during manufacture thereof. 
     
     
         10 . The closure of  claim 8 , wherein said lower portion forms an engagement shoulder for facilitating demolding of said closure during manufacture thereof. 
     
     
         11 . A method of molding a closure including a tamper-evidencing band having an upwardly and inwardly extending retaining rim, said method comprising:
 closing a mold assembly having a cavity, a core, a core sleeve, and a splitter to define the shape of the closure;   withdrawing the cavity away from the core, core sleeve, splitter, and the closure;   staging the core and stripper away from the core sleeve to advance the closure away from the core sleeve;   stopping the core allowing the stripper and the closure to move away from the core;   retracting the core stripper to draw the closure toward the core and abut against the core such that the core stops movement of the closure; and   continuing retraction of the core such that the closure is disengaged from the stripper as the closure abuts against the core.   
     
     
         12 . The method of  claim 11  wherein the retaining rim of the closure flexes thereby allowing the retaining rim to disengage from the core and move past the core as the core is stopped. 
     
     
         13 . The method of  claim 11  wherein the closure includes a plug having an angled outer surface and the plug flexes thereby allowing the plug to disengage from the core and move away from the core as the core is stopped. 
     
     
         14 . The method of  claim 11  wherein an outer surface of the core forms a space between the retaining rim and an outer wall of the tamper-evidencing band. 
     
     
         15 . A closure for sealing the opening of a container having a radially extending locking bead, said closure comprising:
 a top having a periphery;   an annular skirt depending downwardly from said periphery and including a lower edge and a line of weakness extending upwardly from said lower edge; a tear tab extending downwardly from said skirt below said lower edge; and   a tamper-evidencing locking member including an inwardly extending locking ring that extends radially inwardly from said skirt intermediate said top and said bottom edge, the retaining rim including a free edge that is adapted to engage the radially extending locking bead of the container when the closure is removed from the container neck.   
     
     
         16 . The closure of  claim 15  wherein said line of weakness is a scoreline extending vertically from said lower edge. 
     
     
         17 . The closure of  claim 15  wherein said locking ring includes an outwardly directed pleat. 
     
     
         18 . The closure of  claim 15  wherein said locking ring includes a plurality of outwardly directed pleats. 
     
     
         19 . The closure of  claim 15  wherein said locking ring extends radially inwardly and axially upwardly so that said free edge of said locking ring prevents upward movement of said locking ring with respect to the container.