Patent ID: 6537483
Filing Date: 2003-03-25
Classification: B29C

Abstract:
A method of manufacturing a resin impregnated reinforced article having a height h, said method comprising the steps of:providing a permeable reinforcing material on a mold; placing a flexible, impervious sheet over the reinforcing material and sealing the flexible, impervious sheet to the mold to form with the mold a sealed chamber containing the reinforcing material; introducing resin into the reinforcing material so that the resin within the permeable reinforcing material will be at a resin pressure that varies as a function of the height h; drawing a vacuum on the reinforcing material within the sealed chamber; applying liquid pressure on the flexible, impervious sheet and reinforcing material with a reservoir of a liquid in contact with the flexible, impervious sheet on a side thereof opposite the reinforcing material, so that the liquid pressure of the reservoir equalizes the resin pressure as a function of the height h, wherein both the liquid pressure and the resin pressure vary as a function of &rgr;gh, wherein &rgr; is the density of the liquid/resin and g is the gravitational acceleration.