CN102116242B - Method for diagnosing engine misfire - Google Patents
Method for diagnosing engine misfire Download PDFInfo
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- CN102116242B CN102116242B CN201010615738A CN201010615738A CN102116242B CN 102116242 B CN102116242 B CN 102116242B CN 201010615738 A CN201010615738 A CN 201010615738A CN 201010615738 A CN201010615738 A CN 201010615738A CN 102116242 B CN102116242 B CN 102116242B
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Abstract
The invention discloses a method for diagnosing engine misfire. The method comprises the following steps: a single-cylinder single-time misfire statistical quantity is determined according to a first single-cylinder misfire statistical sub-quantity, a second single-cylinder misfire statistical sub-quantity and a third single-cylinder misfire statistical sub-quantity in a single-cylinder single-time misfire diagnosis period; a single-cylinder misfire statistical quantity and the total misfire statistical quantity are determined according to the single-cylinder single-time misfire statistical quantity in the misfire diagnosis statistical period; and the engine misfire situation is determined according to the total misfire statistical quantity and the single-cylinder misfire statistical quantity. In the method for diagnosing engine misfire disclosed by the invention, misfire statistics is conducted according to engine misfire reasons, such as fuel injection failure, abnormal ignition coil return voltage, and the like, and the phenomena occurring during engine misfire, so that whether the engine misfires or not and whether a single cylinder misfires or multiple cylinders misfire can be diagnosed accurately and timely, and the misfiring cylinder can be further determined, which provides convenient conditions for subsequent automobile maintenance.
Description
Technical field
The present invention relates to a kind of engine operating condition diagnostic method, relate in particular to a kind of diagnostic method of engine fire.
Background technique
Spark-ignition engine owing to do not get angry, ignition duration is too short, the oil sprayer fault, fuel metering is inaccurate, compression pressure is too low or other any reasons cause can not burning in the cylinder, just is called engine fire.
With regard to engine management system; Be meant when fire loss ratio (number of times that catches fire accounts for the percentage of total igniting number of times) meets or exceeds the percentage that manufactory declares; To cause pollutant to surpass the limit value of Abgasgesetz regulation, and perhaps cause exhaust gas catalytic converter to cause irreversible damage because of overheated.The rotating speed of motor can change owing to catching fire, and also can be owing to the loosening perhaps clutch abrasion of flywheel changes.
In addition, there is following situation in vehicle during going on the uneven road surface: the caused power of the slight variation of accelerator open degree changes or the variation of driving wheel tractive force can cause engine speed to change.That is: engine fire can cause the curve of crank angle to distort, but causes that the reason of crank angle curvilinear distortion is far above a kind of reason of engine fire.
Though working state calculating diagnostic data and setting threshold according to motor in conventional art compare, but still have following problems: when causing rotating speed to change, can wrong judgement take place to catch fire owing to the reason outside catching fire.If it is disconnected that erroneous judgement takes place, except meeting causes the unnecessary economic burden to the user, car manufactures also can be born very large loss.
Summary of the invention
The present invention is directed to the drawback of existing technology, a kind of diagnostic method of engine fire is provided.
In the diagnostic method of engine fire of the present invention; Set misfire diagnosis measurement period, single cylinder single misfire diagnosis cycle, and set the statistic of catching fire that obtains unusually from the spark coil return voltage be first single cylinder catches fire the statistics component, the oil-break that causes from the oil sprayer fault obtains the statistic of catching fire be second single cylinder catch fire the statistics component, the statistic of catching fire that phenomenon obtains takes place from catching fire is the 3rd single cylinder statistics component that catches fire;
And execution following steps:
Step 1 is confirmed the single cylinder single statistic of catching fire according to first single cylinder of single cylinder single misfire diagnosis in cycle statistics component, second single cylinder statistics component, the 3rd single cylinder statistics component that catches fire that catches fire that catches fire;
Step 2 is confirmed single cylinder the catch fire statistic and the statistic of always catching fire according to the statistic of catching fire of the single cylinder single in the misfire diagnosis measurement period;
Step 3 is confirmed the engine fire situation according to always catch fire statistic and the single cylinder statistic of catching fire.
In the diagnostic method of engine fire of the present invention, be the misfire diagnosis measurement period with the pre-determined number of piston arrives cylinder compresses top dead center in the engine operation process.
In the diagnostic method of engine fire of the present invention, in the said step 1, first single cylinder catch fire statistics component, second single cylinder catch fire the statistics component, be the single cylinder single statistic of catching fire with the 3rd single cylinder statistics component sum of catching fire.
In the diagnostic method of engine fire of the present invention; In the said step 1; The critical value of setting the motor smoothness is the first diagnosis limit value, and is that the 3rd single cylinder catches fire and adds up the component assignment according to the comparative result of present engine smoothness and the first diagnosis limit value.
In the diagnostic method of engine fire of the present invention, said motor smoothness adds up definite according to the first derivative values of the distortion of engine crankshaft corner curve and the rolling mean of second dervative.
In the diagnostic method of engine fire of the present invention, be according to the time lag between twice igniting is carried out obtaining after the self-adaptive processing in the single cylinder single catches fire measurement period to the detection of the distortion of crank angle curve.
In the diagnostic method of engine fire of the present invention, said first single cylinder statistics component and second single cylinder statistics component that catches fire that catches fire is added up by engine electronic control unit.
In the diagnostic method of engine fire of the present invention, in the said step 2, set the single cylinder single corresponding second opinion limit value of statistic that catches fire, said single cylinder single greater than the second opinion limit value statistic sum of catching fire is the single cylinder statistic of catching fire; The single cylinder that each cylinder of said motor the is corresponding statistic sum of catching fire is the statistic of always catching fire.
In the diagnostic method of engine fire of the present invention, in the said step 3, the setting single cylinder catches fire, and the 3rd of statistic correspondence is diagnosed limit value and the disconnected limit value of the four methods of diagnosis of the statistic correspondence of always catching fire;
If the statistic of always catching fire is greater than the disconnected limit value of the four methods of diagnosis, then motor catches fire;
Statistic is greater than the 3rd diagnosis limit value if predetermined single cylinder catches fire, and then this single cylinder catches fire.
In the diagnostic method of engine fire of the present invention, said step 3 further comprises: if confirm that motor catches fire, and predetermined single cylinder catches fire, and then catches fire for any cylinder.
In the diagnostic method of engine fire of the present invention; Beam back phenomenon that engine fire reasons such as voltage is undesired and engine fire the take place statistics of catching fire according to oil sprayer fault or spark coil; Can diagnosis accurately and timely go out motor and whether catch fire, taken place single cylinder and catch fire still that multi-cylinder catches fire and confirms that further which cylinder catches fire, thereby be the follow-up auto repair condition that facilitates.
Description of drawings
Fig. 1 is the schematic flow sheet of the diagnostic method of engine fire according to the invention.
Embodiment
Below in conjunction with accompanying drawing the present invention is done further detailed description, can implement according to this with reference to the specification literal to make those skilled in the art.
In the diagnostic method of engine fire of the present invention; At first need set misfire diagnosis measurement period, single cylinder single misfire diagnosis cycle, and set the statistic of catching fire that obtains unusually from the spark coil return voltage be first single cylinder catches fire the statistics component, the oil-break that causes from the oil sprayer fault obtains the statistic of catching fire be second single cylinder catch fire the statistics component, the statistic of catching fire that phenomenon obtains takes place from catching fire is the 3rd single cylinder statistics component that catches fire.
Wherein, Said misfire diagnosis measurement period is that number of times with piston arrives cylinder compresses top dead center in the engine operation process is a standard; Predetermined number of times; When the number of times of piston arrives cylinder compresses top dead center in the engine operation process conformed to pre-determined number, this misfire diagnosis measurement period finished.In the practical application; This misfire diagnosis measurement period can be represented with counter, the every compression top center of the electronic control unit of motor through a cylinder, and this counter promptly subtracts 1 automatically; When this counter is kept to 0, represent that promptly current misfire diagnosis measurement period finishes.
The described single cylinder single measurement period that catches fire then is as the criterion with the time that piston is accomplished a working stroke.
Said first single cylinder statistics component that catches fire can be beamed back the number of times of electric voltage exception and obtained by spark coil; Said second single cylinder catches fire oil-break number of times that the statistics component can cause by the oil sprayer fault and obtains; Above-mentioned first single cylinder statistics component and second single cylinder statistics component that catches fire that catches fire can be obtained by the electronic control unit statistics of motor, and this type of statistics component belongs to from take place former of engine fire thereby the statistics of carrying out.
Said the 3rd single cylinder statistics component that catches fire then is the phenomenon that takes place from engine fire and the statistics of carrying out.
As shown in Figure 1, after finishing by above-mentioned setting, carry out following steps:
Step 101 is confirmed the single cylinder single statistic of catching fire according to first single cylinder of single cylinder single misfire diagnosis in cycle statistics component, second single cylinder statistics component, the 3rd single cylinder statistics component that catches fire that catches fire that catches fire.
In this step, be the single cylinder single of statistics in the single cylinder single misfire diagnosis cycle statistic of catching fire.This single cylinder single catch fire statistic be first single cylinder catch fire statistics component, second single cylinder catch fire the statistics component, with the 3rd single cylinder statistics component sum of catching fire.
Wherein, because of said first single cylinder statistics component and second single cylinder statistics component that catches fire that catches fire is the information of reflection engine fire reason, so can be by the electronic control unit place acquisition of motor.And the 3rd single cylinder statistics component that catches fire is the information of reflection engine fire phenomenon, obtains so need analyzed according to the motor practical operation situation.
Particularly, the critical value of setting the motor smoothness is the first diagnosis limit value, and is that the 3rd single cylinder catches fire and adds up the component assignment according to the comparative result of present engine smoothness and the first diagnosis limit value.When the motor smoothness greater than first diagnosis during limit value, the catch fire value of statistics component of the 3rd single cylinder is 0, the motor single cylinder does not promptly take place catch fire; When said motor smoothness less than first diagnosis during limit value, then need be the 3rd single cylinder be caught fire and adds up the component assignment with the difference size of the first diagnosis limit value according to this smoothness.
The first diagnosis limit value described here is a preset value, and said present engine smoothness then is to add up definite according to the rolling mean of the first derivative values of the distortion of engine crankshaft corner curve and second dervative.The detection of the distortion of this crank angle curve is in the single cylinder single catches fire measurement period, after the time lag between twice igniting is handled, to obtain; Because tooth profile error causes the erroneous judgement of catching fire, engine electronic control unit carries out self-adaptive processing to the time lag between twice igniting in each single cylinder single catches fire measurement period in order to prevent.
But it is selectable that engine electronic control unit is added up the distortion of engine crankshaft corner curve: motor is not added up in the crank angle curvilinear distortion of shutdown and startup operating mode; When being in towing astern, towing astern oil-break operating mode, do not add up by motor; When engine speed is too high or too low, do not add up; System voltage is crossed and is hanged down when not satisfying the EOBD diagnosis requirement, does not add up; When air inflow is very few, do not add up; Because the distortion of the crank angle curve that the injustice on road surface causes is not added up; The distortion excessive for the closure variable gradient or the air inflow variable gradient is excessive, air-conditioning is opened the crank angle curve in one section special time is not afterwards added up; When the oil tank fuel amount is lower than limit value, do not add up; When detecting camshaft-signal sensor fault, TMAP fault, do not add up.
Step 102 is confirmed single cylinder the catch fire statistic and the statistic of always catching fire according to the statistic of catching fire of the single cylinder single in the misfire diagnosis measurement period;
In this step, set the catch fire second opinion limit value of statistic of reflection single cylinder single,, show that this cylinder catches fire in the single cylinder single catches fire measurement period when the single cylinder single catches fire the numerical value of statistic during greater than this second opinion limit value.Get in the misfire diagnosis measurement period all single cylinder singles greater than this second opinion limit value and catch fire the statistic sum as the single cylinder statistic of catching fire, the described statistic of always catching fire then is the corresponding single cylinder of each cylinder of the motor statistic sum of catching fire.
Step 103 is confirmed the engine fire situation according to always catch fire statistic and the single cylinder statistic of catching fire.
In this step, the setting single cylinder catches fire, and the 3rd of statistic correspondence is diagnosed limit value and the disconnected limit value of the four methods of diagnosis of the statistic correspondence of always catching fire.
If the statistic of always catching fire is greater than the disconnected limit value of the four methods of diagnosis, then motor catches fire; If engine fire does not then take place less than the disconnected limit value of these four methods of diagnosis in the statistic of always catching fire.
Under the aforementioned prerequisite of confirming engine fire, statistic is greater than the 3rd diagnosis limit value if certain predetermined single cylinder catches fire, and single cylinder that then should correspondence catches fire, and can further make sign; Statistic is all diagnosed limit value less than the 3rd if each predetermined single cylinder catches fire, and engine fire has taken place this moment, then belongs to any cylinder of motor this moment and catches fire.
Under the situation that aforementioned single cylinder catches fire, if exist a plurality of single cylinders to catch fire statistic greater than the 3rd diagnosis limit value, then multi-cylinder took place and caught fire in motor this moment.
In the diagnostic method of engine fire of the present invention; In predetermined misfire diagnosis measurement period; The reason that takes place from catching fire and phenomenon two aspects that take place of the catching fire statistics of catching fire, accurately and timely judge the phenomenon of catching fire, and identify the concrete cylinder that catches fire.Maintenance person and user can in time take measures necessary according to this situation, have avoided unnecessary economic burden and extra loss.
Although embodiment of the present invention are open as above; But it is not restricted to listed utilization in specification and the mode of execution; It can be applied to various suitable the field of the invention fully, for being familiar with those skilled in the art, can easily realize other modification; Therefore under the universal that does not deviate from claim and equivalency range and limited, the legend that the present invention is not limited to specific details and illustrates here and describe.
Claims (7)
1. the diagnostic method of an engine fire; It is characterized in that; Set misfire diagnosis measurement period, single cylinder single misfire diagnosis cycle, and set the statistic of catching fire that obtains from the unusual number of times of spark coil return voltage be first single cylinder catches fire the statistics component, the oil-break number of times that causes from the oil sprayer fault obtains the statistic of catching fire be second single cylinder catch fire the statistics component, the statistic of catching fire that phenomenon obtains takes place from catching fire is the 3rd single cylinder statistics component that catches fire;
And execution following steps:
Step 1 is confirmed the single cylinder single statistic of catching fire according to first single cylinder of single cylinder single misfire diagnosis in cycle statistics component, second single cylinder statistics component, the 3rd single cylinder statistics component that catches fire that catches fire that catches fire;
Step 2 is confirmed single cylinder the catch fire statistic and the statistic of always catching fire according to the statistic of catching fire of the single cylinder single in the misfire diagnosis measurement period;
Step 3 is confirmed the engine fire situation according to always catch fire statistic and the single cylinder statistic of catching fire;
Wherein, Said misfire diagnosis measurement period is that number of times with piston arrives cylinder compresses top dead center in the engine operation process is a standard; Predetermined number of times; When the number of times of piston arrives cylinder compresses top dead center in the engine operation process conformed to pre-determined number, this misfire diagnosis measurement period finished; The described single cylinder single measurement period that catches fire then is as the criterion with the time that piston is accomplished a working stroke;
Wherein, the critical value of setting the motor smoothness is the first diagnosis limit value, and is that the 3rd single cylinder catches fire and adds up the component assignment according to the comparative result of present engine smoothness and the first diagnosis limit value;
In the said step 1, first single cylinder catch fire statistics component, second single cylinder catch fire the statistics component, be the single cylinder single statistic of catching fire with the 3rd single cylinder statistics component sum of catching fire;
In the said step 2, set the single cylinder single corresponding second opinion limit value of statistic that catches fire, said single cylinder single greater than the second opinion limit value statistic sum of catching fire is the single cylinder statistic of catching fire; The single cylinder that each cylinder of said motor the is corresponding statistic sum of catching fire is the statistic of always catching fire;
In the said step 3, the setting single cylinder catches fire, and the 3rd of statistic correspondence is diagnosed limit value and the disconnected limit value of the four methods of diagnosis of the statistic correspondence of always catching fire;
If the statistic of always catching fire is greater than the disconnected limit value of the four methods of diagnosis, then motor catches fire;
Statistic is greater than the 3rd diagnosis limit value if predetermined single cylinder catches fire, and then this single cylinder catches fire.
2. the diagnostic method of engine fire as claimed in claim 1 is characterized in that, is the misfire diagnosis measurement period with the pre-determined number of piston arrives cylinder compresses top dead center in the engine operation process.
3. the diagnostic method of engine fire as claimed in claim 2 is characterized in that, said motor smoothness adds up definite according to the first derivative values of the distortion of engine crankshaft corner curve and the rolling mean of second dervative.
4. the diagnostic method of engine fire as claimed in claim 3 is characterized in that, is according to the time lag between twice igniting is carried out obtaining after the self-adaptive processing in the single cylinder single catches fire measurement period to the detection of the distortion of crank angle curve.
5. the diagnostic method of engine fire as claimed in claim 3 is characterized in that, said first single cylinder statistics component and second single cylinder statistics component that catches fire that catches fire is added up by engine electronic control unit.
6. the diagnostic method of engine fire as claimed in claim 1 is characterized in that, said step 3 further comprises: if confirm that motor catches fire, and predetermined single cylinder catches fire, and then catches fire for any cylinder.
7. the diagnostic method of engine fire as claimed in claim 1 is characterized in that, under the situation that aforementioned single cylinder catches fire, if exist a plurality of single cylinders to catch fire statistic greater than the 3rd diagnosis limit value, then motor multi-cylinder took place caught fire this moment.
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CN201010615738A CN102116242B (en) | 2010-12-30 | 2010-12-30 | Method for diagnosing engine misfire |
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CN201010615738A CN102116242B (en) | 2010-12-30 | 2010-12-30 | Method for diagnosing engine misfire |
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CN102116242A CN102116242A (en) | 2011-07-06 |
CN102116242B true CN102116242B (en) | 2012-10-17 |
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Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
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CN106844922A (en) * | 2017-01-11 | 2017-06-13 | 重庆邮电大学 | The engine fire fault diagnosis method with manifold learning is estimated based on cylinder pressure |
CN112523885B (en) * | 2020-11-27 | 2023-04-14 | 江门市大长江集团有限公司 | Method and device for controlling fire in engine |
CN114233552A (en) * | 2021-12-21 | 2022-03-25 | 潍柴动力股份有限公司 | Method and device for determining failure of spark plug, storage medium and electronic equipment |
CN115263548A (en) * | 2022-04-02 | 2022-11-01 | 长城汽车股份有限公司 | Engine fire detection method and device, vehicle and storage medium |
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CN1849445A (en) * | 2003-08-06 | 2006-10-18 | 丰田自动车株式会社 | Control device and misfire determination method for internal combustion engine |
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CN101331044A (en) * | 2006-02-15 | 2008-12-24 | 丰田自动车株式会社 | Misfire determination device, hybrid automobile, and misfire determination method |
CN101469644A (en) * | 2007-12-25 | 2009-07-01 | 比亚迪股份有限公司 | Engine misfire judging method |
CN201680971U (en) * | 2010-04-23 | 2010-12-22 | 阿尔特(中国)汽车技术有限公司 | Fire fault diagnosis device for engine |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
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JPH09228886A (en) * | 1996-02-20 | 1997-09-02 | Matsushita Electric Ind Co Ltd | Misfire detecting method for internal combustion engine and its device |
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Patent Citations (6)
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US5509302A (en) * | 1994-05-02 | 1996-04-23 | Saturn Corporation | Misfire detection in internal combustion engines |
CN1849445A (en) * | 2003-08-06 | 2006-10-18 | 丰田自动车株式会社 | Control device and misfire determination method for internal combustion engine |
CN1884811A (en) * | 2005-06-23 | 2006-12-27 | 株式会社日立制作所 | Misfire detection system for internal combustion engine |
CN101331044A (en) * | 2006-02-15 | 2008-12-24 | 丰田自动车株式会社 | Misfire determination device, hybrid automobile, and misfire determination method |
CN101469644A (en) * | 2007-12-25 | 2009-07-01 | 比亚迪股份有限公司 | Engine misfire judging method |
CN201680971U (en) * | 2010-04-23 | 2010-12-22 | 阿尔特(中国)汽车技术有限公司 | Fire fault diagnosis device for engine |
Non-Patent Citations (1)
Title |
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JP特开平9-228886A 1997.09.02 |
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