US 4,123,307 A · Method for forming hollow shells by rotational casting and winding thereon

Abstract

An apparatus and method are provided for forming large filament reinforced composite bodies. In one form a substrate is formed by rotational molding a plastic material in a mold cavity after which the molding is removed from the cavity and placed in a filament winding fixture wherein filamentary material is wound thereon to provide substantial reinforcement for the article and strengthen the outer stratum thereof. In a particular form, the rotational molding contains a rigid tubular member extending therethrough and secure therein during the rotational molding process and is utilized for the purpose of supporting the rotational molding in the filament winding fixture. In another form, an inflatable substrate is constructed with a rod or tubular member extending therethrough which member is utilized to support the inflated member in a filament winding fixture. Plastic and filamentary material are disposed against the inflated outer surface of the inflatable member in a winding operation which forms a hard, filament reinforced shell on its outer surface. In a particular form, a hard plastic material is spray deposited or otherwise formed on the outer surface of the inflated member while it is rotated in a fixture and after a self supporting shell is formed thereof, glass fibers or other filamentary material is wound against the hard shell as it is rotated in a filament winding fixture.

Claims10

Dependent claims

A method of forming a composite article comprising the steps of:

forming a hollow preform by disposing a structural member across a cavity of a mold, introducing a molding material into said mold cavity and causing said molding material to form a hollow body wherein the opposite end portions of said structural member are integrally secured to respective opposite wall portions of said hollow body during the molding procedure by the solidification of said molding material against said structural member and wherein said opposite end-portions of said structural member are accessible to the exterior of said hollow body,
removing said hollow body with said structural member secured thereacross from said mold and disposing said structural member with the hollow body thereon between the centers of a filament winding fixture with the opposite end-portions of said structural member providing rotational support on said fixture for said hollow body and wherein said structural member defines an axis of rotation for said hollow body,
thereafter power rotating said hollow body on said filament winding fixture while simultaneously winding at least one flexible reinforcing member around at least a portion of the outside surface of said hollow body and bonding said reinforcing member to said outside surface to form a composite body composed of said hollow body, said structural member, and said reinforcing flexible member wound thereon in integral assembly therewith.

Dependencies are inferred from the claim text.

Method for forming hollow shells by rotational casting and winding thereon

Life of this patent

Method for forming hollow shells by rotational casting and winding thereon

Life of this patent

Abstract

Claims10