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:
Dec. 23, 2003
Filed:
Jul. 10, 2002
Noboru Hirano, Kariya, JP;
Nobuhiko Koyama, Nagoya, JP;
Denso Corporation, Aichi-Pref., JP;
Abstract
In an evaporative emission control system, when an engine is running, a negative pressure generated in an air intake pipe of the engine is introduced into a fuel tank through a negative pressure intake line. When the engine halts, a purge valve provided on a purge line connecting the intake pipe and a canister is closed and defines a closed space between the purge valve and the fuel tank. After the negative pressure in the fuel tank is introduced into the closed space and the closed space is maintained under a continuous and uniform negative pressure, the system starts a leak check. Because the negative pressure intake line is provided with a negative pressure maintaining valve, the fuel tank is maintained under the negative pressure when the engine is running.