Patent ID: 6277321
Filing Date: 2001-08-21
Classification: B29C,B29L,B65D

Abstract:
A method of operating a molding machine to form a plastic container having a sidewall with a deep pinch-grip and a base with a high push-up, said method comprising the steps of:providing a preform having a generally tubular body with an average diameter, a wide-mouth at one end with a wide-mouth diameter generally larger than the average diameter, and a closed end at one other end;providing a mold having side molding surfaces defining a protruding portion protruding to a depth approximating the wide-mouth diameter to cause formation of the deep pinch-grip, and a bottom molding surface defining a protruding portion to cause formation of the high push-up;positioning and retaining the preform in the mold;axially stretching the preform toward the bottom molding surface;introducing a first blowing medium into the preform to expand the preform in a controlled manner such that an amount of material extends into a portion of the mold below the protruding portion of the side molding surfaces and such that the body of the preform does not completely conform to the side molding surfaces;moving the bottom molding surface toward the wide-mouth of the preform;introducing a second blowing medium into the preform to expand the preform so that the material below the protruding portion of the side molding surfaces at least substantially conforms to the side molding surfaces and the bottom molding surface to thereby complete the formation of the sidewall and the base of the container; andremoving the container from the mold.