Molding process and apparatus
AssigneeGradual Pty. Ltd.
InventorLaurence A. Boyhan
Life of this patent
Estimating the term…
Abstract
A process and apparatus is provided for molding flowable materials. The mold may be provided with deformable or collapsible mold surfaces and a forming member which is positioned in the mold when producing a shell molded article is also deformable or collapsible. After the molded article is formed the forming member and/or the mold surfaces are deformed or collapsed to facilitate removal of the article from the mold and to avoid "backlocking" of the article in the mold.
Claims8
A process for producing a molded article having an exterior surface and an interior surface, said process including the following sequential steps:
- introducing at atmospheric pressure, sufficient liquid material to form the article into the molding cavity of an open mold wherein the liquid in the mold is maintained at atmospheric pressure throughout the process;
- locating a deformable forming member in said molding cavity, said forming member being formed from a flexible material and being positioned in said molding cavity so that the surfaces of the forming member which form the interior surface of said molded article are spaced from the walls of the mold cavity which forms the exterior surface of said molded article, in a predetermined manner, and, in such a way, that said liquid material in said molding cavity is displaced from the bottom of the molding cavity into the space between the surface of the molding cavity and said deformable forming member;
- solidifying the liquid material;
- deforming the forming member;
- and
- removing said deformed forming member from said molding cavity.
Apparatus for producing a molded article having an exterior surface and an interior surface, including:
- a mold having an opening and a molding cavity, wherein the opening maintains the molding cavity at atmospheric pressure;
- means to introduce sufficient liquid material to produce the molded article into said molding cavity at atmospheric pressure;
- a deformable forming member and means to introduce said deformable forming member into said molding cavity so that said liquid material is displaced around said molding cavity;
- means to move said deformable forming member while in said molding cavity so that the exterior surface of said deformable forming member which forms the interior surface of said molded article is positioned in a predetermined manner in relationship to the walls of the molding cavity, which forms the external surface of said molded article;
- means to deform said deformable forming member after said liquid material has solidified;
- and
- means to remove said deformed forming member from said molding cavity.
Dependencies are inferred from the claim text.