Patent ID: 6578596
Filing Date: 2003-06-17
Classification: B29C,Y10T

Abstract:
A freeze valve apparatus for thermoplastic, comprising:a thermally conductive body heated to a temperature at which a thermoplastic is flowable and having a cavity which contains a thermal insulator; a thermally conductive hollow flow tube defining a flow channel for a flow of the thermoplastic and having an inlet region, an outlet region terminating in an exit orifice and a mid-section between the inlet and outlet regions, the flow tube extending through the thermally conductive body such that its inlet and outlet regions are captured within the thermally conductive body and its mid-section passes through the cavity; and means for directing a flow of coolant having a temperature lower than a lowest flowable temperature of the thermoplastic through the insulator in the cavity and around a portion of the flow tube mid-section, such that heat transfer to the coolant causes solidification of thermoplastic in the flow channel in a region of the flow tube mid-section.