Method and Apparatus for Forming Blow Molded Vessels

Abstract

Methods and apparatus for molding a vessel, such as a bottle, with a high quality sealing surface are described herein. In one embodiment, a stepped blow pin can be used to form the sealing surface of a bottle. A stepped blow pin can include a body with a distal end and a proximal end. The blow pin can include a first region that includes a first diameter and a first engagement surface. The blow pin can further include a second region that includes a second diameter. The second region can be positioned between the first region and the distal end. A transition section can be positioned between the first region and second region. The blow pin can also include a top surface position at the proximal end, and a bottom surface positioned at the distal end.

What is claimed is: 
     
         1 . A vessel comprising:
 (i) a bottle comprising:
 an inner chamber for storing materials; 
 a neck portion comprising:
 a first opening providing access to the environment surrounding the vessel; 
 a second opening providing access to the inner chamber; 
 a first region that defines a neck sealing surface, the first region positioned between the first opening and second opening, where the neck sealing surface is smooth and free of defects; and 
 a second region positioned proximate to the first region; and 
 
   (ii) a cap arranged to be secured to the neck portion and including a cap sealing surface, where the cap sealing surface engages the neck sealing surface when the cap is secured to the neck portion.   
     
     
         2 . The vessel of  claim 1 , wherein the first region has an inner diameter that is less than an inner diameter of the second region. 
     
     
         3 . The vessel of  claim 1 , wherein the second region is positioned between the first region and the second opening. 
     
     
         4 . The vessel of  claim 1 , wherein the first region includes an annular raised region that is positioned along the circumference of the neck. 
     
     
         5 . The vessel of  claim 1 , wherein the cap further comprises a lid and a valve. 
     
     
         6 . The vessel of  claim 5 , wherein the lid has a tab attached on the underside of the lid. 
     
     
         7 . The vessel of  claim 6 , wherein the tab is configured to engage and plug the valve when the lid is closed. 
     
     
         8 . The vessel of  claim 5 , wherein the valve is made from a flexible polymer. 
     
     
         9 . The vessel of  claim 1 , wherein the cap sealing surface is defined by an outer surface of an annular ring that extends from underside of the cap. 
     
     
         10 . The vessel of  claim 1 , wherein the bottle is formed using an extrusion blow molding processes; and
 the cap is formed using an injection molding processes.