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:
Oct. 03, 1978
Filed:
Dec. 10, 1976
Mikio Minoura, Nagoya, JP;
Aisan Industry Co., Ltd., , JP;
Abstract
A system for returning part of exhaust gases from an internal combustion engine through a return passage into an intake passage. Provided in the return passage are a fixed orifice, a pressure chamber downstream thereof, and a regulating valve downstream of the chamber. The regulating valve controls the pressure in the pressure chamber for a proper flow rate of exhaust gases being returned or recirculated. An opening of the regulating valve is so designed as to respond to the movement of a pilot valve provided separately. The pilot valve is actuated in response to a pressure in the pressure chamber, a pressure in a venturi portion in a carburetor, and a pressure in an intake passage downstream of a throttle valve, thereby maintaining the pressure in the pressure chamber at the same level as that in the venturi portion, when the pressure in the intake passage downstream of the throttle valve is over a given pressure level, and maintaining the pressure in the pressure chamber higher than the pressure in the venturi portion, when a pressure in the intake passage downstream of the throttle valve is below a given pressure level (at the time of light load running of an engine). Accordingly, the ratio of recirculating exhaust gas to the intake air is maintained constant, when the pressure in the intake passage is over a given pressure level, and reduced when the aforesaid pressure is below the given pressure level (at the time of light load running of an engine.)