DETECTION SYSTEM FOR INTERNAL COMBUSTION ENGINE KNOCKING

• Main Author: AKAGI YOSHIHIKO
• Format: Patent
• Language: English; Japanese
• Published: 14.06.2018
• Subjects: BLASTING; COMBUSTION ENGINES; CONTROLLING COMBUSTION ENGINES; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; IGNITION, OTHER THAN COMPRESSION IGNITION, FORINTERNAL-COMBUSTION ENGINES; LIGHTING; MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC ORINFRASONIC WAVES; MEASURING; MECHANICAL ENGINEERING; PHYSICS; TESTING; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES; TESTING STATIC OR DYNAMIC BALANCE OF MACHINES ORSTRUCTURES; TESTING STRUCTURES OR APPARATUS NOT OTHERWISE PROVIDED FOR; WEAPONS

PROBLEM TO BE SOLVED: To provide a detection system for internal combustion engine knocking, which can suppress erroneous detection of knocking and can optimally control ignition timing in all operation states.SOLUTION: The detection system for internal combustion engine knocking comprises: a vibration sensor; a frequency analysis part that extracts two or more predetermined frequency components from the vibration detected by the vibration sensor and calculates the intensity of each of the frequency components; an integration part that integrates the intensity of each of the frequency components to calculate the integrated intensity; a background level estimation part that, on the basis of the operation state of the internal combustion engine 7, determines an estimated value of a background level of the internal combustion engine 7; a smoothing part that subtracts the estimated value from the integrated intensity and then smooths the integrated intensity after the subtraction; a knock index calculation part that calculates a knock index showing the degree of knocking on the basis of the smoothed integrated intensity, the estimated value and the integrated intensity; and a determination part that compares the knock index with a determination threshold to determine whether or not knocking occurs in the internal combustion engine 7.SELECTED DRAWING: Figure 10 【課題】ノッキングの誤検出を抑制することができ、全ての運転状態における点火時期を最適に制御可能な内燃機関のノッキング検出システムを提供する。【解決手段】振動センサと、振動センサにより検出された振動から２つ以上の所定の周波数成分を抽出し、各周波数成分の強度を算出する周波数分析部と、各周波数成分の強度を積算して積算強度を算出する積算部と、内燃機関７の運転状態に基づき、内燃機関７のバックグラウンドレベルの推定値を決定するバックグラウンドレベル推定部と、積算強度から推定値を減算した後にその減算後の積算強度を平滑化する平滑化部と、平滑化された積算強度、推定値、および積算強度に基づき、ノッキングの程度を示すノック指標を算出するノック指標算出部と、ノック指標と判定閾値とを比較することにより内燃機関７にノッキングが生じているか否かを判定する判定部と、を備える。【選択図】図１０