Tamper-evident closure

Abstract

A tamper-evident closure system is provided for a container. The system has a body for extending from the container at the container opening. The body defines a dispensing orifice and an attachment surface. The system includes a lid for being moved between a closed position and an open position. An anchor member is provided for being attached to the body attachment surface when the lid is first closed on the body. At least one frangible web initially connects the anchor member with the lid so that the frangible web breaks when the lid is initially lifted from the closed position.

1 . A tamper-evident closure system for a container that has an opening to the container interior, said closure system comprising: 
 a body that is either a separate structure for attaching to, and extending from, said container at said opening or is a unitary extension of said container at said opening, said body having 
 (1) at least one orifice for communicating with said container opening, and  
 (2) a thermoplastic attachment surface;  
   a lid adapted to be disposed on said body for accommodating lifting of said lid relative to said at least one orifice between (1) a closed position over said at least one orifice, and (2) an open position away from said at least one orifice;    an anchor member having a thermoplastic attaching portion for being welded to said body attachment surface when said lid is first in said closed position; and    at least one frangible web extending between said lid and said anchor member for initially connecting said anchor member with said lid for subsequently being broken when said lid is first lifted from said closed position.    
   
   
       2 . The closure system in accordance with  claim 1  further including a welded connection between said attachment surface of said body and said attaching portion of said anchor member.  
   
   
       3 . The closure system in accordance with  claim 1  in which there are two anchor members each having an attachment portion that includes an energy director having a triangular cross section for facilitating ultrasonic welding of the anchor member to said body attachment surface.  
   
   
       4 . The closure system in accordance with  claim 1  in which 
 a portion of said lid has a skirt with a generally cylindrical exterior surface; and    each of said frangible webs has an upper portion molded as a unitary extension from said exterior surface of said lid skirt.    
   
   
       5 . The closure system in accordance with  claim 1  in which each said frangible web has an upper wide portion and a lower narrow portion.  
   
   
       6 . The closure system in accordance with  claim 1  in which 
 a portion of each said anchor member defines a radially inwardly facing surface;    each said frangible web has a lower portion molded as a unitary extension from said anchor member inwardly facing surface.    
   
   
       7 . The closure system in accordance with  claim 1  in which 
 said closure system is a closure for an end of said container wherein the container end defines said container opening; and    said closure includes said body, said lid, said anchor member, and said at least one frangible member.    
   
   
       8 . The closure system in accordance with  claim 7  in which 
 said closure is an article that is separate from said container; and    said body is attachable to said container end over said container opening.    
   
   
       9 . The closure system in accordance with  claim 1  in which said lid, said anchor member, and said at least one frangible member are molded together from a thermoplastic material to form a unitary structure that is initially separate from said closure body.  
   
   
       10 . A tamper-evident closure system for a container that has an opening to the container interior, said closure system comprising: 
 a body that is either a separate structure for attaching to, and extending from, said container at said opening or is a unitary extension of said container at said opening, said body having at least one orifice for communicating with said container opening, and a    a lid adapted to be disposed on said body for accommodating lifting of said lid relative to said at least one orifice between (1) a closed position over said at least one orifice, and (2) an open position away from said at least one orifice, said lid having a lower edge;    an anchor member non-removably fixed to said body when said lid is first in said closed position to define a vertical gap between said anchor member and said lid lower edge; and    at least one frangible web extending across said gap between said lid lower edge and said anchor member for initially connecting said anchor member with said lid for subsequently being broken when said lid is first lifted from said closed position.    
   
   
       11 . The closure system in accordance with  claim 10  in which 
 a portion of said lid has a skirt with a generally cylindrical exterior surface; and    each said frangible web has an upper portion molded as a unitary extension from said exterior surface of said lid skirt.    
   
   
       12 . The closure system in accordance with  claim 10  in which 
 each said frangible web has an upper wide portion and a lower narrow portion; and    the height of said vertical gap between said anchor member and said lid lower edge is greater than the width of said frangible web upper wide portion.    
   
   
       13 . The closure system in accordance with  claim 10  in which 
 a portion of each said anchor member defines a radially inwardly facing surface; and    each said frangible web has a lower portion molded as a unitary extension from said anchor member inwardly facing surface.    
   
   
       14 . The closure system in accordance with  claim 10  in which 
 said closure system is a closure for an end of said container wherein the container end defines said container opening; and    said closure includes said body, said lid, said anchor member, and said at least one frangible member.    
   
   
       15 . The closure system in accordance with  claim 14  in which 
 said closure is an article that is separate from said container; and    said body is attachable to said container end over said container opening.    
   
   
       16 . The closure system in accordance with  claim 10  in which said lid, said anchor member, and said at least one frangible member are molded together from a thermoplastic material to form a unitary structure that is initially separate from said closure body.  
   
   
       17 . A method for making a tamper-evident closure system for a container that has an opening to the container interior, said method comprising the steps of: 
 (A) molding from thermoplastic material a body that 
 (1) is either a separate structure for attaching to, and extending from, said container at said opening or is a unitary extension of said container at said opening,  
 (2) has at least one orifice for communicating with said container opening, and  
 (3) has a thermoplastic attachment surface;  
   (B) molding from thermoplastic material a top structure comprising (1) a lid, (2) an anchor member that has an attaching portion, and (3) at least one frangible web that extends between, and is unitary with, said lid and said anchor member wherein said lid is adapted to be disposed on said body for accommodating lifting of said lid relative to said at least one orifice between (i) a closed position over said at least one orifice, and (ii) an open position away from said at least one orifice;    (C) mounting said top structure on said body with said lid disposed on said body in said closed position and with said anchor member attaching portion located adjacent said body thermoplastic attachment surface; and    (D) welding said anchor member attaching portion to said body thermoplastic attachment surface when said lid is first in said closed position to initially connect said anchor member with said lid so that said at least one frangible web can be subsequently broken when said lid is first lifted from said closed position.    
   
   
       18 . The method in accordance with  claim 17  in which 
 step (B) includes molding said top structure to have said anchor member that has an attaching portion that includes an energy director having a triangular cross section for facilitating ultrasonic welding of the anchor member to said body attachment surface; and    step (D) includes utrasonically welding said anchor member to said body attachment surface.    
   
   
       19 . The method in accordance with  claim 17  in which 
 step (B) includes molding a portion of said lid to have a skirt with a generally cylindrical exterior surface and a lower edge;    step (B) includes molding said anchor member to have an inwardly facing surface; and    step (B) includes molding each of said frangible webs to (1) have an upper portion molded as a unitary extension from said exterior surface of said lid skirt, (2) have a narrower lower portion molded as a unitary extension from said anchor member inwardly facing surface, and (3) have a length sufficient to create a vertical gap between said anchor member and said skirt lower edge wherein the height of said gap is greater than the width of said web upper portion.