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. 20, 1987
Filed:
Jun. 27, 1985
Toshio Iwata, Himeji, JP;
Atsushi Ueda, Himeji, JP;
Abstract
A knock deriving apparatus for an internal combustion engine wherein only a knock signal is precisely derived from the output signal of a knock sensor including a noise signal component by the provision of first and second frequency filters serially connected to the knock sensor. The first frequency filter has a band width wider than that of the second frequency filter to cover a resonant noise. The resultant band width by the series combination of both filters is set to just cover a frequency band where knocks occur. The output of the first frequency filter is converted to a comparative reference signal which is compared in a comparator with the output of the second filter, thereby deriving a stable knock signal.