Vacuum panel base

Abstract

A plastic container having a sidewall and a base merging with the sidewall. The base includes an annular bearing surface and an inner portion for accommodating inner forces tending to collapse the sidewall. The inner portion has a hinge for facilitating the inward collapse of the inner portion, a vacuum panel, and a support ring interposed between the hinge and the vacuum panel for facilitating a flexure of the vacuum panel.

1 . A plastic container comprising: 
 a tubular sidewall;    a base merging with the sidewall, the base including an annular bearing surface comprising a weak point, and an inner portion for accommodating inner forces tending to collapse the sidewall, the inner portion having a hinge for facilitating the inward collapse of the inner portion, a vacuum panel, and a support ring interposed between the hinge and the vacuum panel to maintain the shape of the vacuum panel as the inner portion collapses.    
   
   
       2 . The plastic container according to  claim 1 , wherein the vacuum panel extends outward.  
   
   
       3 . The plastic container according to  claim 1 , wherein at least one of the vacuum panel or the inner portion flexes inward when a vacuum is created inside the plastic container.  
   
   
       4 . The plastic container according to  claim 1 , wherein the annular bearing surface curls inward at the weak point to further facilitate the inward collapse of the inner portion.  
   
   
       5 . The plastic container according to  claim 3 , wherein the inner portion flexes by an amount sufficient to prevent deformation of the annular bearing surface when a vacuum is created inside the container.  
   
   
       6 . The plastic container according to  claim 4 , wherein the inner portion flexes without deforming at least one of the sidewall and the base.  
   
   
       7 . The plastic container according to  claim 1 , wherein the sidewall is substantially cylindrical.  
   
   
       8 . The plastic container according to  claim 1 , wherein the sidewall is substantially smooth.  
   
   
       9 . The plastic container according to  claim 1 , wherein the plastic container is composed of polyolefin.  
   
   
       10 . The plastic container according to  claim 9 , wherein the polyolefin is polyethylene or polypropylene.  
   
   
       11 . A plastic container comprising: 
 a substantially cylindrical sidewall;    a base merging with the sidewall, the base including an annular bearing surface comprising a weak point, and an inner portion having an annular hinge, a support ring, and a vacuum panel surrounded by the annular hinge and the support ring,    wherein the inner portion extends outward under a first state and flexes inward when a vacuum is created inside the plastic container.    
   
   
       12 . The plastic container according to  claim 11 , wherein the inner portion flexes without deforming at least one of the sidewall and the base.  
   
   
       13 . The plastic container according to  claim 11 , wherein the sidewall is substantially smooth.  
   
   
       14 . The plastic container according to  claim 11 , wherein the plastic container comprises a plastic.  
   
   
       15 . The plastic container according to  claim 14 , wherein the plastic is a polyolefin.  
   
   
       16 . The plastic container according to  claim 15 , wherein the polyolefin is selected from polyethylene and polypropylene.  
   
   
       17 . The plastic container according to  claim 11 , wherein the annular bearing surface curls inward at the weak point to further facilitate the inward collapse of the inner portion.  
   
   
       18 . A plastic container comprising: 
 a substantially smooth, cylindrical sidewall;    a base merging with the sidewall, the base including an annular bearing surface comprising a weak point, and an inner portion having an annular hinge, a support ring, and a vacuum panel surrounded by the annular hinge and the support ring,    wherein the inner portion extends outward under a first state and flexes inward when a vacuum is created inside the plastic container without deforming the at least one of the sidewall and the base.    
   
   
       19 . The plastic container according to  claim 18 , wherein the plastic container is composed of polyolefin.  
   
   
       20 . The plastic container according to  claim 19 , wherein the plastic container is composed of polyethylene.  
   
   
       21 . The plastic container according to  claim 19 , wherein the plastic container is composed of polypropylene.  
   
   
       22 . The plastic container according to  claim 18 , wherein the annular bearing surface curls inward at the weak point to further facilitate the inward collapse of the inner portion.