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:
Sep. 22, 1992
Filed:
Jul. 01, 1991
Applicant:
Inventor:
William A Nelson, New Baltimore, MI (US);
Assignee:
Automotive Plastic Technologies, Inc., Sterling Heights, MI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B29C / ;
U.S. Cl.
CPC ...
425130 ; 264572 ; 425562 ; 425563 ; 425564 ;
Abstract
A check valve is provided that is especially useful in gas-assisted injection molding wherein pressurized gas is injected into molten plastic material. A tapered or cone-shaped valve member which seats into a correspondingly tapered or cone-shaped valve chamber provides the mechanism by which the valve seals against reverse flow. Any plastic material entering the gas passageway would contact the base end of the tapered or cone-shaped valve member and not any sealing surfaces. By minimizing contact with the sealing surfaces, the useful lifetime of the check valve is significantly increased.