INTERNAL COMBUSTION ENGINE KNOCK CONTROLLING APPARATUS

• US 20130245924A1
• Filed: 07/18/2012
• Published: 09/19/2013
• Est. Priority Date: 03/14/2012
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: MATSUSHIMA, Yuhei
• Granted Patent: US 9,164,012 B2
• Time in Patent Office: Days
• US Class Current: 701/111
• CPC Class Codes: F02D 2041/1432 the system including a filter, e.g. a low pass or high pass filter
• CPC Class Codes: F02D 2041/286 comprising means for signal processing
• CPC Class Codes: F02D 35/027 using knock sensors
• CPC Class Codes: G01L 23/221 for detecting or indicating knocks in internal combustion engines
• CPC Class Codes: G01M 15/12 by monitoring vibrations

Abstract

An internal combustion engine knock controlling apparatus is obtained that improves knock detection performance by making a correction period appropriate without performing matching, when calculating a transition correction factor for correcting a filter coefficient used for calculating a mean value and a standard deviation of a knock signal in a transitional operation state. A previous value of a filter coefficient for calculating a knock determination threshold value that has been corrected by a transition correction factor is used for a filter coefficient for calculating the transition correction factor so that the response characteristics are made equal between a filtering process used for calculating a transition correction factor for correcting a knock determination threshold value and a filtering process used for calculating the knock determination threshold value in a transition operation period.

Claims

1. An internal combustion engine knock controlling apparatus comprising:

a sensor outputting a signal based on vibration of an internal combustion engine;

knock signal calculating means for calculating, from the output from the sensor, a characteristic component of knock occurring in the internal combustion engine as a knock signal at every ignition timing;

knock signal standard statistic calculating means for calculating a standard statistic of the knock signal by filtering processing the knock signal calculated by the knock signal calculating means;

knock determination threshold calculating means for calculating a knock determination threshold value for determining knock based on the standard statistic of the knock signal calculated by the knock signal standard statistic calculating means;

knock determination means for determining that knock has occurred if the knock signal calculated by the knock signal standard statistic calculating means exceeds the knock determination threshold value calculated by the knock determination threshold calculating means;

operating state value detecting means for detecting a plurality of operating state values each indicating an operating condition of the internal combustion engine;

operating state value deviation normalization means for normalizing deviations between the operating state values detected by the operating state value detecting means and values obtained by filtering processing the operating state values, using a representative value of the operating state values,

transition correction factor calculating means for calculating a transition correction factor based on a plurality of post-normalization operating state value deviations calculated by the operating state value deviation normalization means;

filter coefficient correcting means for correcting a filter coefficient used in a filtering process of the knock signal standard statistic calculating means based on the transition correction factor calculated by the transition correction factor calculating means; and

filter characteristic adjusting means for adjusting a response characteristic of the filtering process in the operating state value deviation normalization means to be equal to a response characteristic of the filtering process in the knock signal standard statistic calculating means.

2. The internal combustion engine knock controlling apparatus according to claim 1, wherein the filter characteristic adjusting means uses a previous value of the filter coefficient calculated by the filter coefficient correcting means as the filter coefficient used in the filtering process in the operating state value deviation normalization means.

3. The internal combustion engine knock controlling apparatus according to claim 1, wherein the process of the operating state value deviation normalization means is performed with the same period as the process of the knock signal standard statistic calculating means.

4. The internal combustion engine knock controlling apparatus according to claim 2, wherein the process of the operating state value deviation normalization means is performed with the same period as the process of the knock signal standard statistic calculating means.