The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 08, 1977
Filed:
Aug. 18, 1975
Samuel J Rupert, Ann Arbor, MI (US);
Hoover Ball and Bearing Company, Saline, MI (US);
Abstract
An improved method of blow molding thermoplastic articles of superior physical properties by orienting the material during the formation of the articles. A two-stage blowing operation is provided wherein a tubular parison is extruded at a preblowing station spaced from a separate final blowing station and simultaneously a previously blown preform is supported on a blow pin at the final blowing station. A preform blow mold is closed on the tubular parison while a final blow mold is closed on the previously blown preform and the enclosed tubular parison and preform are blown to the shapes of the enclosing molds. The blow pin is then retracted from the final blow mold, and the molds are shifted so that the preform blow mold is at the final blowing station, and the final blow mold is at a discharge station. The blow pin is then inserted into the mold at the final blowing station so that the preform in the mold will be supported on the blow pin. Both molds are then opened and are shifted back to the preblowing and final blowing stations, and the cycle is repeated. The preform is conditioned both thermally and dimensionally in the molds for most effective orientation during the final blowing operation.