Bottle-type plastic container

Abstract

A bottle-type plastic container has a barrel portion and an opening at one end region of the barrel, for allowing liquid contents to be charged into the container and discharged therefrom. The barrel portion has a generally polygonal cross-section defined by a plurality of substantially flat walls, and a plurality of part-cylindrical corner walls extending contiguously between the flat walls. The flat walls each has a shape that is deflected inwards as the liquid contents charged into the container at a high temperature is cooled, to absorb a pressure drop within the container. The corner walls each has a center line of curvature extending in parallel with a longitudinal axis of the container, and a radius of curvature that decreases as the pressure drop is absorbed by the flat walls.

1 . A bottle-type plastic container comprising a barrel portion and an opening in one end region of the barrel, for allowing liquid contents to be charged into the container and discharged therefrom; 
 said barrel portion having a generally polygonal cross-section that is defined by a plurality of substantially flat walls, and further having a plurality of part-cylindrical corner walls extending contiguously between said flat walls;    said flat walls each having a shape that is deflected inwards as the liquid contents charged into the container at a high temperature is cooled, to thereby absorb a pressure drop within the container; and    said corner walls each having a center line of curvature that extends in parallel with a longitudinal axis of the container, and having a radius of curvature that decreases as the pressure drop is absorbed by the deflection of the flat walls.    
     
     
         2 . A bottle-type plastic container according to    claim 1   , wherein each of said flat walls has at least one reinforcing rib.  
     
     
         3 . A bottle-type plastic container according to    claim 2   , wherein each of said at least one reinforcing rib extends in a direction that is parallel to a surface on which the container is adapted to stand.  
     
     
         4 . A bottle-type plastic container according to    claim 1   , wherein at least two of said flat walls are parallel to each other.  
     
     
         5 . A bottle-type plastic container according to    claim 1   , wherein said barrel portion has a generally square cross-section.