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:
May. 18, 1999
Filed:
Jul. 02, 1997
Katsushi Hashizume, Susono, JP;
Kazuhisa Mogi, Susono, JP;
Toyota Jidosha Kabushiki Kaisha, Aichi-ken, JP;
Abstract
The invention provides a preignition detection device that is capable of detecting a preignition condition (PI) in an incipient stage. Engine vibration is detected by a vibration sensor 113 and read into a controller 12. When the length of a period during which abnormal vibration of a magnitude greater than a predetermined level occurs in succession has exceeded a predetermined length of period, or when the frequency of occurrence of abnormal vibration during a predetermined period is greater than a predetermined value and the cumulative sum of the frequencies of occurrence of abnormal vibration has exceeded a predetermined value, then it is determined that preignition has occurred. Here, a determination value, based on which the occurrence of preignition is determined, can be varied to prevent erroneous decisions and to improve responsiveness.