Patent ID: 6773655
Filing Date: 2004-08-10
Classification: B29C,Y10T

Abstract:
A method of forming a composite structure comprising:providing a tool for forming a composite structure by vacuum assisted resin transfer molding, said tool comprising: a mold surface and a vacuum bag arranged with said mold surface to form a mold cavity for receiving a part to be impregnated with resin; at least a portion of said vacuum bag being formed from a self-supporting sheet material having a texture formed by upraised portions on a first side of said sheet material, said upraised portions being closely spaced valleys defined between the upraised portions, said valleys forming a resin distribution network, said self-supporting sheet material having a predetermined shaped contour in addition to said texture, said sheet material rigid enough to retain the predetermined shaped contour as a mold in addition to retaining the resin distribution network, but flexible enough to collapse as a sheet against the part under a vacuum applied during the vacuum assisted resin transfer molding; and a main feeder channel having a cross-sectional area larger than a cross-sectional area of said valleys being provided in fluid communication with said valleys and extending along a portion of said tool to provide resin to said resin distribution network; providing the part to be molded in said mold cavity; sealing said mold cavity; connecting a source of uncured resin to said main feeder channel; connecting said mold cavity to a vacuum outlet; moving said uncured resin through said main feeder channel and said resin distribution network to said vacuum outlet to fill said part in said mold cavity to impregnate said part; and curing said uncured resin to form a composite structure.