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:
Apr. 24, 1984
Filed:
Jun. 18, 1982
Franz Sellmaier, Schwieberdingen, DE;
Bernward Boning, Ludwigsburg, DE;
Rudolf Nagel, Asperg, DE;
Rainer Bone, Vaihingen, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
In order to eliminate from an ion current sensor signals which are not derived from knocking of an engine, the ion current sensor signal is evaluated by a high-pass - low-pass filter to filter out signals of frequencies extraneous to knocking frequencies, using, preferably, a digital filter including two timing stages (11, 13) connected to a counter; to inhibit response of the circuit, an interrupter switch (8) is included in the evaluation circuit, which is opened upon sensing of disturbance signals due to ignition events, for example upon occurrence of ignition, by setting a timing stage (20) which maintains the switch open, and thus inhibits evaluation of oscillatory signals from the ion current sensor (1) for the timing duration thereof. To store previously counted oscillatory signals, a further timing stage (21) can be provided, likewise connected to the ignition signal and enabled at the initiation of current flow through the primary of an ignition coil to prevent resetting of the counter for the timing duration thereof.