Process for the automatic inspection of blow-molded articles
AssigneeE. I. Du Pont de Nemours and Company
InventorsGeorge Joseph Ostapchenko, Terrance Duane Phillips
Life of this patent
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Abstract
Blow-molded thermoplastic articles such as bottles are produced from preforms while measuring the pressure in the article and comparing the measured pressure with standard values. Articles having measured pressure values which deviate from standard are rejected.
Claims6
In a blow-molding process wherein a heated thermoplastic preform having a prefinished neck, sidewall, and closed bottom is (1) placed in a mold, (2) is axially stretched by an inserted mandrel while partially inflating the preform, and (3) is then completely inflated against the mold under increased pressure to form a hollow thermoplastic article, the improvement wherein the hollow thermoplastic article is produced while
- a. measuring fluid pressure variations in the preform as it is inflated,
- b. comparing the measured fluid pressure variations with a standard pressure trace representative of commercial quality, hollow thermoplastic articles, and
- c. rejecting hollow thermoplastic articles having fluid pressure measurements which deviate substantially from the standard pressure trace.
Dependencies are inferred from the claim text.