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:
Mar. 18, 2014
Filed:
Mar. 16, 2011
Naoyuki Yamagata, Higashihiroshima, JP;
Akira Kageyama, Hiroshima, JP;
Takeshi Nagasawa, Hiroshima, JP;
Naoyuki Yamagata, Higashihiroshima, JP;
Akira Kageyama, Hiroshima, JP;
Takeshi Nagasawa, Hiroshima, JP;
Mazda Motor Corporation, Hiroshima, JP;
Abstract
Provided is an exhaust system of a multi-cylinder engine capable of increasing the air-intake and thereby increasing the engine output with a simple configuration. The exhaust system is provided with low velocity-side passages, high velocity-side passages, a low velocity-side collection part, a high velocity-side collection part, and a flow passage area variable valvecapable of changing the flow passage area of the respective high velocity-side passages. The relationship of a diameter aof a true circle with a same area as the flow passage area of the downstream end of the low velocity-side passages, a diameter Dof a true circle with a same area as the flow passage area of the downstream end of the low velocity-side collection part, a diameter aof a true circle with a same area as the flow passage area of the downstream end of the high velocity-side passages, and a diameter Dof a true circle with a same area as the flow passage area of the downstream end of the high velocity-side collection partis made to be a/D≧a/D. In a low velocity region R, an exhaust valveis opened during the overlap period of an intake valveand the exhaust valveand the flow passage area of the high velocity-side passagesis narrowed, and, in a high velocity region R, the flow passage area of the high velocity-side passagesis set to be a maximum area.