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:
Feb. 19, 1991
Filed:
Jun. 13, 1989
Koji Sakakibara, Hekinan, JP;
Yoshihiko Hirata, Obu, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A knock control system for the internal combustion engine is disclosed in which a knock intensity value V is detected from a signal produced by a knock sensor, a cumulative percentage point V.sub.P of distribution of a substantially logarithmic conversion value of the knock intensity value V is detected, a value S corresponding to the standard deviation of the substantially logarithmic conversion value is detected, and a knock decision level V.sub.KD is prepared on the basis of V.sub.P and S, thereby controlling knock control factors such as ignition timing and air-fuel ratio. The control system further comprises a device for deciding whether a predetermined period has passed after the engine enters specified operating conditions, a device for averaging knock intensity values, and an update quantity setting device for increasing the unit quantity of updating the averaging device and/or the cumulative percentage point detection device only while the predetermined period has not passed.