Patent ID: 6461561
Filing Date: 2002-10-08
Classification: B29C,Y10S

Abstract:
A method for molding a thin thermoplastic shell having a generally nonplanar shape in a mold arrangement including a generally hollow and elongate mold housing having a thin mold shell provided on one side thereof and along with a back surface of said mold shell defining an air chamber extending longitudinally within the interior of said mold housing and further including a plurality of air flow control regions therewithin each including a selected number of centrifugal fans nonrotatably mounted on a rotatable shaft, said method comprising the steps of:providing an elongate tubular member disposed within the interior of said mold housing and extending along substantially the entire longitudinal extent thereof; providing said plurality of centrifugal fans at spaced-apart locations from one another within discharge channels defined within said mold housing and which open into said air chamber; supplying heated air into said tubular member and discharging heated air along substantially the entire longitudinal extent thereof directly into feed channels defined within said mold housing between adjacent pair of said discharge channels; discharging heated air at a high velocity into said air chamber and along said back surface of said mold shell; individually controlling said shafts separately from other ones of said shafts to control flow of heated air into said air chamber and toward said back surface of said mold shell; depositing thermoplastic material on an inner surface of said thin mold shell; and fusing said thermoplastic material against said inner surface of said thin mold shell to form said thin thermoplastic shell.