Patent ID: 6406288
Filing Date: 2002-06-18
Classification: B21C,B29C,B29K,Y10T

Abstract:
An apparatus for extrusion molding comprising:a) an extruding die for extruding a material into a hollow tubular molding; b) a first clamping device arranged to clamp a first molding portion; c) a second clamping device arranged to clamp a second molding portion, said first and second clamping devices being positioned along the length of the molding in a spaced relationship and configured to clamp the molding independently of one another, wherein said first clamping device clamps said first molding portion to permit stretching thereof and said second clamping device is arranged to clamp said second molding portion after said first clamping device clamps said first molding portion to thereby form an air-tight space within the molding between the first and second clamping devices; d) a molding die including a pair of corresponding die cavity halves closeable around the air-tight space of the molding between the clamping devices to compress the molding and conform same to a final product configuration of the die cavity; and e) means for releasing compressed air from the final product configuration wherein said means releases compressed air from said final product configuration of said molding before said die cavity halves are fully separated.