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:
Mar. 09, 1999
Filed:
May. 06, 1998
Charles Henry Covert, Manchester, NY (US);
Kenneth William Turner, Webster, NY (US);
Thomas Charles Meiller, Pittsford, NY (US);
General Motors Corporation, Detroit, MI (US);
Abstract
An air control valve assembly for the air side of an automotive fuel evaporative emission control system incorporates two passive check valves and an active blocking valve which cooperate to divide the air filtered air inlet path from the air exit path to atmosphere. The possibility of break through vapors flowing back into the air cleaner during canister vapor fill is avoided through the use of oppositely opening check valves. By adding an active blocking valve below the freely movable air inlet check valve, the canister can be rigorously sealed from the atmosphere during a diagnostic evacuation test.