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:
Jul. 07, 2015
Filed:
Sep. 05, 2012
Akito Itou, Kariya, JP;
Ryotaro Kuno, Ichinomiya, JP;
Daisuke Kawakami, Anjo, JP;
DENSO CORPORATION, Kariya, JP;
Abstract
An abnormal combustion detection apparatus detects an abnormal combustion of an internal combustion based on a vibration waveform from a vibration sensor attached to the internal combustion engine. A gain circuit of the apparatus amplifies or attenuates the vibration waveform from the vibration sensor, an AD conversion circuit converts a waveform provided by the gain circuit to digital data, and a gain switching unit switches a gain of the gain circuit from a small gain value to a large gain value at a gain switch timing. The gain switching unit separates a large abnormal combustion from a small abnormal combustion in an abnormal combustion determination period for maximizing a dynamic range of an AD conversion circuit and for securely detecting a change of waveform amplitude in case of gain switching in an abnormal combustion detection operation.