Patent ID: 7691315

Claim:
A method of molding resin, comprising: providing a mold having a plurality of cavities, wherein said mold includes two mold parts which may be opened and closed; providing a resin and plasticating said resin in a heated injection molding machine; providing a runner system which fluidly connects said injection molding machine with a first cavity through a gate; providing a sub-gate between said first cavity and a second cavity, the first and second cavity located in series along a common axial centerline, the first and second cavities being like-shaped; wherein said first cavity has a width “w 1 ” and height “h 1 ” and a “(w/h) 1 ” ratio of about 0.33-3.0 and said second cavity has a width “w 2 ” and height “h 2 ” and a “(w/h) 2 ” ratio of about 0.33-3.0 wherein said first cavity has a first region adjacent said gate that has a first cross-sectional area (w×h) 1 , and a second region adjacent said subgate with a second cross-sectional area (w×h) 2 wherein (w×h) 1 <(w×h) 2 and said second cavity has a first region adjacent said subgate that has a first cross-sectional area (w×h) 2 , wherein (w×h) 2 >(w×h) 1 ; injecting said resin through said runner system and into said first cavity at a pressure in the range of about 1000 psi to about 2500 psi to substantially fill said first cavity and continuing to inject resin through said sub-gate into said second cavity; and cooling said resin thereby forming a molded resin.