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:
Aug. 28, 1984
Filed:
Jul. 12, 1982
Siegfried Rohde, Schwieberdingen, DE;
Jorg Bonitz, Muhlacker, DE;
Robert Entenmann, Benningen, DE;
Rochus Knab, Kornwestheim, DE;
Herbert Schramm, Stuttgart, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A knocking sensor (10) which provides output signals representative of combustion condition under knocking to thereby generate knocking signals which have mixed therewith noise or stray interference signals, and which also furnishes noise or stray interference signals under other than knocking combustion conditions, has its output connected to a plurality of parallel connected selective filters (2, 3). The filters have different pass band frequencies. One of the filters (3) is tuned to sense knocking frequencies, one or more other filters (2) being tuned to preferentially select noise or interference signals. A selection and discriminating circuit (10) having comparators (11) is provided connected to the filters to eliminate noise signals by comparing the signal level of the output received from the filters with a reference, which may be a dynamic reference, the outputs from the discriminators being processed in a logic circuit (15) to provide output signals (18) if (1) the filtered signal having the frequencies expected upon knocking exceeds a threshold level and (2) the filtered signal having the frequency band of the stray, or noise signals is below a threshold level and, preferably, a knocking signal persists for a time in excess of a time interval as determined by a timing circuit (16). Preferably, non-linear circuits such as logarithmic circuits (4, 5), are connected between the outputs from the filters (2, 3) and the comparators (11, 12) of the selection or recognition or discriminating circuit (10).