Patent ID: 7115226

Claim:
A method of improving melt flow in a stack injection molding apparatus comprising: providing a first transfer nozzle having a first melt channel for receiving a melt stream from a melt source, said melt stream having a first temperature and viscosity distribution; providing a second transfer nozzle having a second melt channel for receiving said melt stream from said first melt channel, wherein one of said first or second transfer nozzles includes a movable valve pin for controlling the flow of the melt stream between said first transfer nozzle and said second transfer nozzle; providing a melt homogenizing element coupled to said valve pin for changing said melt stream from said first temperature and viscosity distribution to a second temperature and viscosity distribution, wherein said second temperature and viscosity distribution is more uniform than said first temperature and viscosity distribution; and transferring the melt stream from the first transfer nozzle to the second transfer nozzle through the melt homogenizing element.