Apparatus for making a thin walled container from a plastic resin
AssigneeCosden Technology, Inc.
InventorsJackie D. Murley, Marion Johnson
Life of this patent
Estimating the term…
Abstract
The apparatus for making thin-walled containers from plastic resins includes a heater for raising the temperature of the resin sheet, a product mold and a preform mold located in axial alignment and movable relative together. The preform mold includes a reciprocal piston that is arranged, when the molds are closed on the resin sheet, to be moved in response to fluid pressure to force the sheet into the product mold while gas pressure is applied to the interior of the sheet to force the resin sheet into the final product configuration. The elongation of the sheet by the piston and the radial deformation caused by the gas, biaxially orient the material to increase the strength of the container.
Claims5
In improved apparatus for thermoforming an article from a thermoplastic resin sheet wherein the apparatus includes means for heating the sheet and a source of pressure gas, the improvement comprising:
- first and second mold platens each having at least one mold recess therein and moveable relatively together and apart, at least one mold recess in each said platen in alignment with the mold recess in the other said mold platen;
- gas control means for connecting said recesses to the source of pressure gas and for venting said recesses;
- an article mold located in the mold recess in said second mold platen, said mold including a wall defining the configuration of said article and having a plurality of gas ports extending therethrough whereby the exterior of said article can be, at times, exposed to said pressure gas and at other times vented;
- a preform mold located in the mold recess in said first mold platen, said mold including a wall forming an annular cavity therein, a plurality of gas ports extending through said wall, and pressure-actuated piston means located in said preform mold and moveable between upper and lower limits by said gas into the cavity in said article mold to aid in displacing said resin sheet into said article mold to form said article.
Dependencies are inferred from the claim text.