Patent ID: 6991756

Claim:
A method for performing heat exchange for a metal mold by a heat exchange apparatus, said apparatus comprising: a heat exchange passage provided for said metal mold; a first supply unit for supplying a hot heat carrier to said heat exchange passage; a second supply unit for supplying a cold heat carrier to said heat exchange passage; a plurality of valves; a plurality of pipes; and a plurality of air supply units for supplying air to said heat exchange passage so that said hot and cold heat carriers are purged when supply of said hot and cold heat carriers is switched, said method comprising the steps of: heating said metal mold to a predetermined high temperature with said hot heat carrier supplied to said heat exchange passage by said first supply unit; stopping supply of said hot heat carrier supplied by said first supply unit; filling a melted resin into a cavity of said metal mold; purging said hot heat carrier remaining in said heat exchange passage by air supplied by at least one of said plurality of air supply units; cooling said metal mold to a predetermined low temperature with said cold heat carrier supplied to said heat exchange passage by said second supply unit; stopping supply of said cold heat carrier supplied by said second supply unit; and extracting a cured product from said metal mold, wherein a first air supply unit from said plurality of air supply units purges said hot heat carrier and a second air supply unit from said plurality of air supply units purges said cold heat carrier.