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. 11, 1979
Filed:
May. 30, 1978
Nobuaki Wakita, Susono, JP;
Eiji Hashimoto, Susono, JP;
Toyota Jidosha Kogyo Kabushiki Kaisha, Toyota, JP;
Abstract
Disclosed herein is an apparatus for cleaning the exhaust gas of an internal combustion engine, which apparatus includes an exhaust gas recirculation system provided with a back-pressure control mechanism for maintaining a predetermined constant pressure of recirculated exhaust gas in a recirculation passageway, and an air injection system connecting an air pump with an exhaust system of the engine. An air-flow control valve having two vacuum chambers arranged between the air injection system and the exhaust gas recirculation system for controlling, in two stages, the amount of air diverted from the air injection system to the recirculation passageway. One of the chambers is directly connected to a vacuum source in the intake system of the engine. While the other is connected, via a vacuum delay unit, to the vacuum source.