Blow molded plastic container and method of making

Abstract

A molded polymeric container that is shaped to be easier to mold, have improved rigidity under pressure and improved strength includes a substantially cylindrical body portion having a longitudinal axis and a circumferential sidewall, and a bottom portion. The bottom portion includes a central pushup area that is substantially symmetrical about the longitudinal axis and that is substantially flat. The pushup area preferably has a radius that is within the range of 0.100 inches to 0.500 inches. The bottom portion further includes a plurality of support feet surrounding and protruding downwardly from the pushup area, each of which has a bottom support surface and a pair of sidewalls that help define a valley between the support feet. The sidewalls have a substantially straight portion that defines an angle with respect to a line that is perpendicular to the longitudinal axis, and this angle is at least 25 degrees.

What is claimed is:  
     
         1 . A molded polymeric container that is shaped to be easier to mold, have improved rigidity under pressure and improved strength with respect to such containers heretofore known, comprising: 
 a substantially cylindrical body portion having a longitudinal axis and a circumferential sidewall; and    a bottom portion comprising: 
 a central pushup area that is substantially symmetrical about the longitudinal axis, said pushup area being substantially flat and having a radius that is within the range of 0.100 inches to 0.500 inches;  
 a plurality of support feet surrounding and protruding downwardly from the pushup area, each of the support feet having a bottom support surface and a pair of sidewalls, each of said sidewalls helping define a valley between said support feet, and wherein at least one of said sidewalls has a substantially straight portion that defines an angle with respect to a line that is perpendicular to the longitudinal axis, said angle being at least 25 degrees; and 
 a plurality of ribs positioned in said valleys between said support feet, each of the ribs being positioned between and helping to define two of the support feet.  
 
   
     
     
         2 . A container according to  claim 1 , wherein said pushup area has a radius that is approximately 0.150 inches.  
     
     
         3 . A container according to  claim 1 , wherein said angle is approximately 30 degrees.  
     
     
         4 . A container according to  claim 3 , wherein each of said sidewalls contains a substantially straight portion.  
     
     
         5 . A container according to  claim 1 , wherein each of said sidewalls contains a substantially straight portion.  
     
     
         6 . A molded polymeric container that is shaped to be easier to mold, have improved rigidity under pressure and improved strength with respect to such containers heretofore known, comprising: 
 a substantially cylindrical body portion having a longitudinal axis and a circumferential sidewall; and    a bottom portion comprising: 
 a plurality of downwardly protruding support feet, each of the support feet having a bottom support surface and a pair of sidewalls, each of said sidewalls helping define a valley between said support feet, and wherein at least one of said sidewalls has a substantially straight portion that defines an angle with respect to a line that is perpendicular to the longitudinal axis, said angle being at least 25 degrees, whereby the container bottom is easier to mold than those heretofore known.  
   
     
     
         7 . A container according to  claim 6 , wherein said angle is approximately 30 degrees.  
     
     
         8 . A container according to  claim 8 , wherein each of said sidewalls contains a substantially straight portion.