Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Nippon Soken, Inc.

Norihito Hanai

Rihito Kaneko

Kenji Senda

Yasuhiro Yamasako

Kenji Kasashima

Masatomo Yoshihara

Shuhei Oe

Satoshi Masuda

Yuichi Takemura

Satoshi Watanabe

Yuuichi Takemura

Hiroto Tanaka

Masaaki Yamaguchi

Takayuki Hosogi

Yuki Nose

Yoshiyuki Shogenji

Keiichi Myojo

Eiji Ikuta

Masanori Toya

Kouzi Ohara

Misako Ban

Hisayuki Ito

A pre-ignition determining apparatus for an internal combustion engine using hydrogen as fuel is configured to determine an occurrence of pre-ignition based on an output value of a vibration sensor provided in the internal combustion engine. The pre-ignition determining apparatus includes processing circuitry that is configured to execute an accumulation process of calculating an accumulated value of the output value within a prescribed period prior to an ignition timing of an air-fuel mixture, and a determination process of determining the occurrence of pre-ignition based on the accumulated value.

Pre-ignition determining apparatus for internal combustion engine

An engine controller includes an ignition timing control unit and a rich imbalance determining unit. The rich imbalance determining unit designates one of multiple cylinders as a subject cylinder for determination and executes lean active control that commands a smaller amount of fuel injection for the subject cylinder than for the other cylinders. The rich imbalance determining unit determines whether an air-fuel ratio of the subject cylinder deviates to be richer based on a rotational fluctuation amount of a crankshaft during the execution of the lean active control. The ignition timing control unit executes an advancement limiting process that limits advancement of the ignition timing by the knock control during the execution of the lean active control.

Engine controller and engine control method

A CPU advances ignition timing within a range in which knocking can be suppressed by feedback control based on an output signal of a knocking sensor. The CPU sets the igniting timing based on a feedback adjustment amount and a learning value. The CPU limits timing advancing update of the learning value when an exhaust pressure is higher than or equal to a threshold.

Ignition timing controller and control method for internal combustion engine

A control device for an internal combustion engine includes an electronic control unit configured to determine whether or not cylinder-specific air-fuel ratio processing is being executed in which an air-fuel ratio of at least one of a plurality of cylinders is controlled to be a rich air-fuel ratio and an air-fuel ratio of at least one of the other cylinders is controlled to be a lean air-fuel ratio. The electronic control unit updates a first learning value in which a result of comparison between a knock strength of the internal combustion engine and a first determination value is reflected when the cylinder-specific air-fuel ratio processing is not being executed. The electronic control unit prohibits updating of the first learning value and calculates a target ignition timing of the internal combustion engine based on the first learning value when the cylinder-specific air-fuel ratio processing is being executed.

Control device for internal combustion engine

An engine ECU executes operations including: extracting vibration intensities of a plurality of frequency bands from vibration detected by a knock sensor, multiplying the extracted vibration intensity of each frequency band by a weight coefficient and adding the results in correspondence with crank angles to calculate integrated values of every five degrees; calculating a coefficient of correlation based on a result of comparison between a vibration waveform of a frequency band and a knock waveform model prepared in advance; calculating a knock intensity; determining occurrence of knocking in accordance with the calculated coefficient of correlation and the knock intensity; and determining no occurrence of knocking in accordance with the calculated coefficient of correlation and the knock intensity.

Knock determination device and knock determination method for internal combustion engine

An output signal of a knock sensor is filtered with a plurality of band-pass filters to extract vibration waveform components of a plurality of frequency bands (f-f). Weighting coefficients (G-G) which multiply the vibration waveform component of each frequency band are established in such a manner as to be a small value as a noise intensity of each frequency band becomes larger. Thereby, the vibration waveform component of a plurality of frequency bands is synthesized by weighting according to an influence of a noise intensity of each frequency band. Even when the noise is superimposed on the vibration waveform component of any of the frequency bands, it becomes possible to reduce the influence of the noise and to synthesize the vibration waveform component of each frequency band, and an accurate knock determination can be performed based on the composite vibration waveform.

Knock determining device

An engine ECU executes a program including: detecting a magnitude of vibration of an engine; detecting a vibration waveform of the engine based on the magnitude; calculating a correlation coefficient, in the case where the engine speed is smaller than a threshold value, using the sum of values each determined by subtracting a positive reference value from a magnitude of a knock waveform model, as an area of the knock waveform model and, calculating the correlation coefficient, in the case where the engine speed is not smaller than the threshold value, using the area of the whole knock waveform model; and determining whether or not knocking has occurred using the correlation coefficient. The correlation coefficient is calculated by dividing by the area the sum of differences that are each the difference between the magnitude on the vibration waveform and the magnitude on the knock waveform model.

Knocking determination device and knocking determination method for internal combustion engine

An engine ECU executes a program including the steps of: calculating a knock magnitude N by dividing an integrated value lpkknk obtained by integrating the magnitude of vibration in the knock detection gate by BGL; controlling ignition timing according to a result of comparison between knock magnitude N and a determination value VJ; stopping updating of a standard deviation &#x3c3; when it is determined that determination value VJ to be compared with knock magnitude N is to be changed; updating a median value VM by increasing an update amount of median value VM; and updating BGL according to median value VM and standard deviation &#x3c3;.

Ignition timing controlling apparatus and ignition timing controlling method for internal combustion engine

An engine ECU executes a program including calculating a correlation coefficient by dividing the sum of respective absolute values, which are each a difference between a magnitude in an engine vibration waveform and a magnitude in a knock waveform model for every crank angle, by an area corresponding to magnitudes equal to or larger than a positive reference value in the knock waveform model, and determining whether or not knocking has occurred based on the correlation coefficient.

Device and method for determining knocking of internal combustion engine

A 90&#xb0; integrated value calculating unit of an engine ECU calculates a 90&#xb0; integrated value obtained by integrating a magnitude. A calculating unit calculates a knock magnitude by dividing 90&#xb0; integrated value by a BGL. A value obtained by subtracting a standard deviation &#x3c3; from a median value of 90&#xb0; integrated value is determined as the BGL. An ignition timing control unit controls the ignition timing depending on whether knock magnitude is equal to or larger than a determination value. A median value calculating unit calculates median value of 90&#xb0; integrated value. A standard deviation calculating unit calculates standard deviation of 90&#xb0; integrated value. A first stop unit stops updating of median value and standard deviation when 90&#xb0; integrated value is smaller than a first threshold value or is equal to or larger than a second threshold value.

An engine ECU executes a program including the steps of: calculating a coefficient of correlation K in accordance with a result of comparing a waveform of a vibration of a frequency band including a resonance frequency of an engine with a knock waveform model previously created as a waveform of a vibration caused when the engine knocks; calculating a knock intensity N from an intensity of a vibration of a frequency band excluding the resonance frequency of the engine; if knock intensity N is larger than a reference value and coefficient of correlation K is larger than a threshold value, determining that the engine knocks; and if knock intensity N is smaller than the reference value and/or coefficient of correlation K is smaller than the threshold value, determining that the engine does not knock.

Knock determination device and method for internal combustion engine

An engine ECU executes a program including: the step of increasing a determination value by a correction amount if the number of knock intensities not lower than the determination value is not smaller than a threshold value among knock intensities of a plurality of predetermined number of continuous ignition cycles; and the step of increasing the determination value by a correction amount if the number of knock intensities not smaller than the determination value is not smaller than a threshold value, among knock intensities of a plurality of ignition cycles satisfying the condition that a coefficient of correlation calculated by comparing a vibration waveform and a knock waveform model is not smaller than a threshold value, of the knock intensities of a plurality of predetermined continuous ignition cycles.

Internal combustion engine knock determination device and knock determination method

An engine ECU executes: calculating 15-degrees integrated value integrating vibration intensity for each of six crank angle ranges; detecting an amount of change in the 15-degrees integrated value between ignition cycles; specifying two ranges having larger amounts of change; specifying a crank angle having intensity larger than that of a neighboring crank angle in a search range determined to be the same as the specified ranges; calculating a coefficient of correlation K corresponding to a difference between a vibration waveform and a knock waveform model while the specified crank angle is matched with a timing at which intensity peaks in the knock waveform model; and, if the coefficient of correlation K is larger than a threshold value K(), determining that knock has occurred.

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Norihito Hanai