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:
Jun. 20, 1995
Filed:
Jan. 25, 1994
Thomas J Fournier, Tucson, AZ (US);
Envirotest Systems Corp., Tucson, AZ (US);
Abstract
An apparatus and method for the non-intrusive testing of evaporative fuel vapor systems of motor vehicles. A portable pressure control and monitoring unit is inserted into the fuel filler neck of a vehicle. The vapor vent line, leading from the fuel tank to the charcoal canister of the evaporative system, is temporarily clamped off. Pressurized gas is introduced into the unit from an operator's console, expanding a ring bladder and sealing an annular volume between the unit and the filler neck. Gas is then passed through the unit into the contained volume of the evaporative system. After the neck cap is replaced, an automatic timer deflates the ring bladder, charging the remaining volume of the evaporative system. Pressure decay data is collected and stored in the unit's digital storage device. Initially, this data is used in a pass/fail determination made by a microprocessor in the unit. Later, the data is downloaded into a separate computer for archival purposes.