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:
Jan. 28, 2014
Filed:
Mar. 01, 2011
Naoya Matsuo, Higashihiroshima, JP;
Kouji Shishime, Hiroshima, JP;
Motoo Hayakawa, Kure, JP;
Hiroki Morimoto, Hiroshima, JP;
Mikinori Ohashi, Hiroshima, JP;
Naoya Matsuo, Higashihiroshima, JP;
Kouji Shishime, Hiroshima, JP;
Motoo Hayakawa, Kure, JP;
Hiroki Morimoto, Hiroshima, JP;
Mikinori Ohashi, Hiroshima, JP;
Mazda Motor Corporation, Hiroshima, JP;
Abstract
When a maximum value of vibration intensity (maximum vibration intensity)(Vmax) acquired from a vibration sensor () in a low engine speed/high engine load (operating region (R)) is equal to or greater than a given threshold value (X), a spark timing of a spark plug () is shifted from a point set in a normal state on a retard side with respect to a compression top dead center, farther toward the retard side. Then, when a maximum vibration intensity (Vmax) acquired after the spark timing retard is greater than a maximum vibration intensity (Vmax) acquired before the spark timing retard, it is determined that preignition occurs. This technique makes it possible to reliably detect preignition using the vibration sensor, while distinguishing the preignition from knocking. An in-cylinder pressure sensor for detecting an in-cylinder pressure of an engine may be used to determine the presence or absence of the preignition, in the same manner.