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:
Aug. 10, 2004
Filed:
Oct. 08, 2002
Yoshihiro Majima, Inuyama, JP;
Denso Corporation, Kariya, JP;
Abstract
A valve timing control device for an internal combustion engine, in which upon cold start, combustion gas containing quench hydrocarbons and wet fuel is confined in a combustion chamber by advancing an exhaust valve close timing. This combustion gas is richer in hydrocarbons and wet fuel than is the gas produced after the engine has been warmed up. When the pressure in an intake line becomes lower than 600 mmHg, the exhaust valve close timing is retarded so as to recirculate post-combustion gas back to the combustion chamber. Then the unburned hydrocarbons in the post-combustion gas are involved in combustion again and their emission is reduced. Such gas recirculation and confinement to the combustion chamber are switched in accordance with a target valve underlap corresponding to the intake line pressure in the internal combustion engine.