Child-Resistant Closure

Abstract

A child-resistant closure has an inner member and an outer member encircling the inner member for gripping by a user. The outer member comprises a sidewall bearing a first engagement feature and an upper web underside bearing a second engagement feature. The inner member comprises: an inner sidewall bearing an internal thread for engaging the container body; an outer sidewall spaced-apart from the inner sidewall and bearing a third engagement feature, the third engagement feature engagable to the first engagement feature responsive to an upward movement of the outer member so as to allow the outer member to transmit a removal rotation to the inner member. An upper web joins the inner sidewall and outer sidewall and has an upper surface bearing a fourth engagement feature engagable to the second engagement feature to transmit an installing rotation to the inner member.

What is claimed is: 
     
         1 . A child-resistant closure for closing an externally threaded neck of a container body, the cap comprising:
 an inner member having an internal thread for engaging the neck external thread; and   an outer member encircling the inner member for gripping by a user,   
       wherein:
 the outer member comprises:
 a sidewall bearing a first engagement feature; and 
 an upper web having an underside bearing a second engagement feature; and 
 
 the inner member comprises:
 an inner sidewall bearing the internal thread; 
 an outer sidewall spaced-apart from the inner sidewall and bearing a third engagement feature, the third engagement feature engagable to the first engagement feature responsive to an upward movement of the outer member so as to allow the outer member to transmit a removal rotation to the inner member; and 
 an upper web joining the inner sidewall and outer sidewall and having an upper surface bearing a fourth engagement feature, the fourth engagement feature engagable to the second engagement feature to transmit an installing rotation to the inner member. 
 
 
     
     
         2 . The child-resistant closure of  claim 1  wherein:
 the outer member upper web has a central aperture exposing the inner member upper web. 
 
     
     
         3 . The child-resistant closure of  claim 1  wherein:
 the first engagement feature comprises one or more gaps in a radially inwardly projecting feature of the outer member sidewall. 
 
     
     
         4 . The child-resistant closure of  claim 1  wherein:
 the inner member is formed as a first single-piece plastic molding; and 
 the outer member is formed as a second single-piece plastic molding. 
 
     
     
         5 . The child-resistant closure of  claim 1  wherein:
 the outer member sidewall first engagement feature comprises at least one gap in a radially inwardly projecting bead; and 
 the inner member outer sidewall third engagement feature comprises at least one downward projection from the inner member outer sidewall. 
 
     
     
         6 . The child-resistant closure of  claim 5  wherein:
 the outer member upper web second engagement feature comprises a first plurality of barbs; and 
 the inner member upper web fourth engagement feature comprises a second plurality of barbs. 
 
     
     
         7 . The child-resistant closure of  claim 6  wherein:
 the first plurality of barbs and second plurality of barbs are positioned to engage each other during installation and angled so that an installing torque drives the outer member downward into firmer engagement with the inner member thus requiring the user to provide no downward pressure to install. 
 
     
     
         8 . The child-resistant closure of  claim 7  wherein:
 the first plurality of barbs and second plurality of barbs have surfaces angled so that an uninstalling rotation of the outer member causes the surfaces to cam against each other lifting the outer member up and out of driving engagement with the inner member. 
 
     
     
         9 . A container comprising:
 the child-resistant closure of  claim 1 ; and   a container body having an externally threaded neck engaged to the inner member internal thread.   
     
     
         10 . A method for using the container of  claim 9 , the method comprising:
 upwardly pulling the outer member sidewall; and   rotating the outer member sidewall in a direction to unscrew the internal thread from the external thread.   
     
     
         11 . The method of  claim 10  wherein:
 the upwardly pulling causes the third engagement feature to engage the first engagement feature. 
 
     
     
         12 . A method for manufacturing the container of  claim 9 , the method comprising:
 downwardly installing the outer member over the inner member, the downward installation outwardly flexing a lower rim portion of the outer member and then relaxing to capture the inner member.   
     
     
         13 . A child-resistant closure for closing an externally threaded neck of a container body, the cap comprising:
 an inner member having an internal thread for engaging the neck external thread; and   an outer member encircling the inner member for gripping by a user,   
       wherein:
 the outer member comprises:
 a sidewall bearing a first engagement feature; and 
 an upper web having an underside bearing a second engagement feature; and 
 
 the inner member comprises:
 a sidewall having an outer surface bearing a third engagement feature, the third engagement feature engagable to the first engagement feature responsive to upward movement of the outer member so as to allow the outer member to transmit a removal rotation to the inner member; and 
 an upper surface bearing a fourth engagement feature, the fourth engagement feature engagable to the second engagement feature to transmit an installing rotation to the inner member. 
 
 
     
     
         14 . A method for manufacturing the closure of  claim 13 , the method comprising:
 downwardly installing the outer member over the inner member, the downward installation outwardly flexing the sidewall of the outer member and then relaxing to capture the inner member.