Unitary molded plastic structures

Abstract

Abstract A method and apparatus for molding insulated reinforced plastic structures for use as refrigerated cargo containers and truck or trailer bodies. The insulated reinforced plastic structures have substantially parallel opposed sides and are molded as a unitary structure in a single molding operation. Glass fiber reinforcing materials, which include an insulating core material, are placed in the bottom of a female mold and up against the sides. A somewhat loose fitting mandrel braced vertically but which may later be expanded laterally, is lowered down in between the materials at the sides and on top of materials at the bottom. Further glass fiber reinforcing materials, including a core material are placed on top of the mandrel. A male mold is lowered in place on top of these materials but somewhat short of full final closing. A free flowing liquid plastic resin is pumped within the space defined by the male and female molds and the mandrel. The free flowing liquid plastic resin impregnates the glass fiber reinforcing and wets the surfaces of the core material. The male mold is closed fully downward and the mandrel expanded fully laterally, compressing the glass fiber reinforcing and compacting the entire material assembly in its final form. The liquid plastic resin then hardens, the molds are opened, and the molding is removed from the mold.

Inventors

• 👤 John F Reeves

Bibliographic Details