CN112683540A - Method for quickly diagnosing carbon deposition degree of engine combustion chamber with convenient use - Google Patents
Method for quickly diagnosing carbon deposition degree of engine combustion chamber with convenient use Download PDFInfo
- Publication number
- CN112683540A CN112683540A CN202011421026.5A CN202011421026A CN112683540A CN 112683540 A CN112683540 A CN 112683540A CN 202011421026 A CN202011421026 A CN 202011421026A CN 112683540 A CN112683540 A CN 112683540A
- Authority
- CN
- China
- Prior art keywords
- engine
- imin
- imax
- combustion chamber
- fault
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 56
- 229910052799 carbon Inorganic materials 0.000 title claims abstract description 56
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 42
- 230000008021 deposition Effects 0.000 title claims abstract description 39
- 238000000034 method Methods 0.000 title claims abstract description 38
- 238000003745 diagnosis Methods 0.000 claims abstract description 31
- 238000012360 testing method Methods 0.000 claims description 26
- 238000000354 decomposition reaction Methods 0.000 claims description 9
- 238000012549 training Methods 0.000 claims description 7
- 238000006243 chemical reaction Methods 0.000 claims description 5
- 230000005540 biological transmission Effects 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 230000000712 assembly Effects 0.000 claims description 3
- 238000000429 assembly Methods 0.000 claims description 3
- 238000009792 diffusion process Methods 0.000 claims description 3
- 238000005286 illumination Methods 0.000 claims description 3
- 230000007935 neutral effect Effects 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 3
- 238000012067 mathematical method Methods 0.000 abstract description 3
- 238000004891 communication Methods 0.000 description 6
- 239000011324 bead Substances 0.000 description 5
- 238000012423 maintenance Methods 0.000 description 4
- 238000012545 processing Methods 0.000 description 3
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 2
- 230000003044 adaptive effect Effects 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 229910052744 lithium Inorganic materials 0.000 description 2
- 238000012935 Averaging Methods 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000000889 atomisation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000002405 diagnostic procedure Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 239000012188 paraffin wax Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M15/00—Testing of engines
- G01M15/04—Testing internal-combustion engines
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/47—Scattering, i.e. diffuse reflection
Landscapes
- Chemical & Material Sciences (AREA)
- General Physics & Mathematics (AREA)
- Physics & Mathematics (AREA)
- General Health & Medical Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Engineering & Computer Science (AREA)
- Combustion & Propulsion (AREA)
- Testing Of Engines (AREA)
Abstract
本发明具体涉及使用方便的快速诊断发动机燃烧室积碳程度的方法，将光源组件和光电接收组件安装在发动机相应位置后，利用发动机燃烧室内积碳程度不同时，光照在其内部后经反射和漫射的光线强度不一样，从而得到不同的电流信号来判断发动机燃烧室积碳程度，信号精度更好，电流信号对比时采用双限制误差对比的效果，即最大值和最小值分别对比并将两个对比结果采用数学方法处理，诊断的正确率也较高。
The invention specifically relates to an easy-to-use method for quickly diagnosing the degree of carbon deposition in an engine combustion chamber. After the light source assembly and the photoelectric receiving assembly are installed at corresponding positions of the engine, when the degree of carbon deposition in the engine combustion chamber is different, the light is reflected and reflected inside the engine combustion chamber. The intensity of diffused light is different, so different current signals are obtained to judge the degree of carbon deposition in the engine combustion chamber. The signal accuracy is better. The effect of double-limit error comparison is used when comparing current signals, that is, the maximum and minimum values are compared separately and The two comparison results are processed using mathematical methods, and the accuracy of diagnosis is also high.
Description
The application has the following application numbers: 201910519095.0, filing date: 2019-06-13, the patent name "method for rapidly diagnosing carbon deposition degree of engine combustion chamber", and the patent application thereof.
Technical Field
The invention relates to the field of maintenance and diagnosis of automobile engine parts, in particular to a method for quickly diagnosing the degree of carbon deposition in an engine combustion chamber, which is convenient to use.
Background
With the continuous development of the automobile industry, the total market volume of the automobile warranty equipment industry is showing a rapid increase trend, and the demand of people on convenient and good-universality engine diagnosis tools is increasing day by day;
after the engine is used for a long time, carbon deposits usually occur in a combustion chamber of the engine, because when the power of the engine comes from the downward movement of a piston, a mixture of gasoline and air is sucked into a cylinder, then the upward moving piston compresses the oil gas into highly combustible gas, finally a spark plug is ignited to detonate the highly combustible gas, the piston is pushed by the strong explosive force, and the engine generates power. The source of power, namely mixed gas, must enter a combustion chamber through an inlet valve; a small amount of gasoline can be attached to the intake valve, hydrocarbon, paraffin and colloid which cannot be completely combusted in the gasoline can be burnt into colloidal carbon substances when the gasoline meets the high temperature of the combustion chamber, and if the oil nozzle is polluted, the sprayed gasoline is not good in atomization state, the gasoline and air are not uniformly mixed, and the amount of the gasoline condensed on the intake valve can be increased. What is worse, the colloidal carbon has the characteristic of absorbing gasoline, so the layer of carbon deposit can absorb gasoline, the absorbed gasoline is burnt into the colloidal carbon to form thicker carbon deposit, and the thicker carbon deposit can absorb more gasoline, thus vicious circulation is carried out until an inlet valve cannot be tightly closed due to too much carbon deposit, and an engine cannot run.
The cylinder wall, the piston up end, the cylinder cap medial surface that constitute the combustion chamber to and the valve surface all can produce the carbon deposit, in order to diagnose the carbon deposit condition, traditional practice only is with whole the dismantling hoist and mount of engine from the engine compartment, then with cylinder cap and cylinder body separation, in order to look over the condition of combustion chamber, but the process of demolising is very consuming time, and can influence the mounted position of cylinder cap and cylinder body and the sealing performance before both, probably lead to the performance degradation of engine after reinstallating, therefore traditional carbon deposit diagnostic mode is comparatively laggard.
The current new diagnostic technology is an engine endoscope, and the working principle of the engine endoscope is that a spark plug at the upper end of a cylinder cover is pulled out without detaching the cylinder cover, then the endoscope with a camera is inserted into a combustion chamber from a spark plug seat, and then the carbon deposition condition in the combustion chamber is diagnosed according to image or video data. However, the severity of the carbon deposition is judged by the experience of technicians during diagnosis, the observation is limited by the visual range of a camera, the carbon deposition on the surface of a valve is difficult to see, the engine is prohibited after the endoscope is inserted, the endoscope needs to be moved slowly and observed carefully if accurate diagnosis is needed due to different upward positions of pistons in cylinders, the diagnosis process usually takes about thirty minutes, if the number of cylinders of the engine is large, such as a V6 or V8 diesel engine, the diagnosis process takes longer, the endoscope diagnosis mode is usually carried out after the engine cannot work or has a large problem, and the routine engine maintenance does not have the item.
However, the formation time of the carbon deposit of the engine is not fixed according to the influence of factors such as the use habits of a driver, the environment, oil products and the like, so the carbon deposit condition of the combustion chamber should be diagnosed after the engine is used for a certain distance, and the existing disassembly type diagnosis or endoscope diagnosis mode only can adopt a mode of diagnosis after a fault due to long time consumption and cannot meet the use requirements of the existing automobile.
Disclosure of Invention
In view of the above problems, the present invention aims to provide a method for quickly diagnosing the degree of carbon deposition in the combustion chamber of an engine, which is convenient to use.
In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows: 1. a method for quickly diagnosing the degree of carbon deposition in a combustion chamber of an engine comprises the following steps of firstly defining one or more engines which can be normally used and have complete parts as test engines, wherein the surfaces of a valve, the inner side wall of an air cylinder body and the upper surface of a piston in the test engines are in a normal state without carbon deposition, and the engines can be normally started; the test engine is normally installed on the corresponding type of automobile;
then replacing the normal state valve or cylinder block or piston of one or more positions in the test engine with a fault state valve or fault state cylinder block or fault state piston, wherein the engine is defined as a fault engine; the failure state is that carbon deposition is adhered on the surfaces of the valve, the cylinder body or the piston respectively; according to the adhesion degree of the carbon deposit, the fault states are classified into mild, moderate and severe; after the replacement is finished, the fault engine is normally installed on the automobile with the corresponding model;
defining an engine with unknown state to be diagnosed as an engine to be detected, wherein the engine to be detected is directly installed on a vehicle to be diagnosed and is not detached;
the method is characterized in that: the rapid diagnosis method comprises the following steps: firstly, placing an automobile transmission provided with a test engine in a neutral gear; removing all spark plugs on a cylinder cover of the test engine, mounting a photoelectric receiving assembly on one spark plug seat, and mounting a corresponding number of light source assemblies on the remaining one or more spark plugs; a bolt with the same specification as the thread of the spark plug is arranged on the spark plug seat which is not provided with the photoelectric receiving assembly or the light source assembly; then the following steps are carried out in sequence:
a. turning on an LED lamp in the light source component; igniting by using an automobile key or a key starting button for a period of time, wherein the spark plug is detached, and the engine is driven by the starting motor to rotate at a low speed; the piston in the combustion chamber moves up and down, and the intake valve and the exhaust valve are opened or closed periodically, and the light of the LED lamp positioned in the combustion chamber is transmitted to the vicinity of the photoelectric receiving component in a reflection or diffusion mode in the combustion chamber; when the rotating speed r of the engine exceeds a certain value r1, a photoelectric sensor in the photoelectric receiving assembly starts to receive light illumination to form a current signal, the current signal is sent to the microcomputer through the A/D conversion module, and the signal receiving is stopped after a certain time T;
b. the test engine is replaced by a fault engine, and the number, position and degree of faults in the fault engine are arranged and combined to obtain n fault engines in different states and needing to be tested; repeating the step a for each faulty engine in the permutation and combination mode;
c. replacing the failed engine with the engine to be tested, and repeating the step a;
d. and c, comparing the data obtained in the step c with the data obtained in the step a and the step b, and defining the engine state with the closest comparison result as the state of the engine to be tested.
Preferably, in the step a, the microcomputer takes the collected current signal as a training sample, and performs EMD adaptive decomposition on the current signal x (t) in the training sample, wherein the decomposition method is as follows:
in the above formula, n is the number of decomposed IMF components; cjRepresents the jth IMF component, j 1,2,3.., n; r isnIs the residual component;
decomposing the mixture to obtain n CjAfter the components, each C is calculated separatelyjSelecting two C with the highest kurtosis value and the second highest kurtosis valuejPerforming linear superposition to obtain a current signal of the characteristic highlight after EMD noise reduction, and then averagely dividing the obtained current signal of the characteristic highlight into m sections according to the time length, and recording the m sections as S1-Sm;
extracting a current wave crest value Imax and a current wave trough value Imin from S1-Sm to obtain S1- [ Imax-0, Imin-0], S2- [ Imax-0, Imin-0] … … Sm- [ Imax-0, Imin-0], and storing data into a database;
in the step b, the faulty engine in the first permutation and combination mode obtains data S1- [ Imax-1, Imin-1], S2- [ Imax-1, Imin-1] … … Sm- [ Imax-1, Imin-1], and so on, and the faulty engine in the nth permutation and combination mode obtains data S1- [ Imax-n, Imin-n ], S2- [ Imax-n, Imin-n ] … … Sm- [ Imax-n, Imin-n ]; and storing the data into a database;
in the step c, data S1- [ Imax-x, Imin-x ], S2- [ Imax-x, Imin-x ] … … Sm- [ Imax-x, Imin-x ] obtained by the engine to be tested;
in the step d, the [ Imax-x and Imin-x ] are respectively compared with the [ Imax-0 and Imin-0] … … [ Imax-n and Imin-n ].
Preferably, in the step d, the absolute value of the subtraction between Imax-x in the S1 th engine to be tested and Imax-0 in the S1 th database is defined as Δ max-0, and the absolute value of the subtraction between Imin-x in the S1 th engine to be tested and Imin-0 in the S1 th database is defined as Δ min-0; then calculated as follows:
replacing S1 with S2 … … Sm to give Δ 2 … … Δ m;
d, calculating the delta 1-delta m obtained in the step d according to the following formula:
sequentially replacing [ Imax-0 and Imin-0] in the step d with [ Imax-1 and Imin-1] … … [ Imax-n and Imin-n ], and repeating the steps to obtain mu 1 … … mu n; and taking the minimum value mu-min in mu 0-mu n, and marking the state of the engine corresponding to the mu-min as the state of the engine to be tested.
The invention has the following beneficial effects: the method comprises the steps that different current signals are obtained to judge the carbon deposition degree of the engine combustion chamber by utilizing the fact that the reflected and diffused light rays irradiated inside the engine combustion chamber have different intensities when the carbon deposition degree in the engine combustion chamber is different, the judging process is rapid, fewer disassembled parts are needed, and the diagnosis time period is short; the effect of double-limit error comparison is adopted during current signal comparison, namely the maximum value and the minimum value are respectively compared and the two comparison results are processed by a mathematical method, so that the accuracy of the comparison results is high, and after multi-section comparison is adopted and the comparison errors are appropriately combined, the data result is still correct, so that the diagnosis accuracy is also high.
Drawings
FIG. 1 is a schematic view of a light source assembly mounted on a spark plug socket;
FIG. 2 is a schematic view of the structure of the photoelectric receiving assembly mounted on the spark plug seat;
fig. 3 is a flow chart of the diagnostic device performing a diagnosis.
Detailed Description
As shown in fig. 3, the method for quickly diagnosing the degree of carbon deposition in the combustion chamber of the engine, which is convenient to use, includes the steps of firstly defining one or more engines which can be normally used and have complete parts as test engines, wherein the surfaces of a valve, an air cylinder body and a piston in the test engines are in a normal state without carbon deposition, and the engines can be normally started; the test engine is normally installed on the corresponding type of automobile;
then replacing the normal state valve or cylinder block or piston of one or more positions in the test engine with a fault state valve or fault state cylinder block or fault state piston, wherein the engine is defined as a fault engine; the failure state is that carbon deposition is adhered on the surfaces of the valve, the cylinder body or the piston respectively; for example, the failure positions may be valve carbon deposition, cylinder wall carbon deposition, and piston top carbon deposition, or the three parts may be in a failure state at the same time, or any two of the parts may be in a failure state; according to the adhesion degree of the carbon deposit, the fault states are classified into mild, moderate and severe; after the replacement is finished, the fault engine is normally installed on the automobile with the corresponding model;
defining an engine with unknown state to be diagnosed as an engine to be detected, wherein the engine to be detected is directly installed on a vehicle to be diagnosed and is not detached;
the rapid diagnosis method comprises the following steps: firstly, placing an automobile transmission provided with a test engine in a neutral gear; removing all spark plugs on a cylinder cover of the test engine, mounting a photoelectric receiving assembly on one spark plug seat, and mounting a corresponding number of light source assemblies on the remaining one or more spark plugs; a bolt with the same specification as the thread of the spark plug is arranged on the spark plug seat which is not provided with the photoelectric receiving assembly or the light source assembly; then the following steps are carried out in sequence:
a. turning on an LED lamp in the light source component; igniting by using an automobile key or a one-key starting button for a period of time, wherein the recommended ignition duration time range is 2s-4s, the spark plug is removed at the moment, and the engine is driven by a starting motor to rotate at a low speed; the piston in the combustion chamber moves up and down, and the intake valve and the exhaust valve are opened or closed periodically, and the light of the LED lamp positioned in the combustion chamber is transmitted to the vicinity of the photoelectric receiving component in a reflection or diffusion mode in the combustion chamber; the microcomputer is also in communication connection with an OBD diagnosis interface installed on the automobile through an OBD special data line and reads the rotating speed of the engine in real time; when the rotating speed r of the engine exceeds a certain value r1, a photoelectric sensor in the photoelectric receiving assembly starts to receive light illumination to form a current signal, the current signal is sent to the microcomputer through the A/D conversion module, and the signal receiving is stopped after a certain time T; the microcomputer and the automobile OBD interface can be connected by directly installing a wireless signal type OBD data diagnostic instrument on the automobile OBD interface, wireless data signals started by the data diagnostic instrument are transmitted to a wireless signal receiving module additionally installed on the microcomputer, and all the OBD wireless signal sending/receiving modules are mature products and can be directly purchased in the market.
The microcomputer 24 takes the collected current signal as a training sample, and performs EMD adaptive decomposition on the current signal x (t) in the training sample, and the EMD method is a method often used in current signal analysis, and can be theoretically applied to decomposition of any type of time series (signals), so that the method has obvious advantages in processing non-stationary and non-linear data compared with the conventional stationary method. The decomposition method comprises the following steps:
in the above formula, n is the number of decomposed IMF components; cjRepresents the jth IMF component, j 1,2,3.., n; r isnIs the residual component;
in the above formula, the basic process of decomposition of x (t) is as follows:
finding out all maximum value points of the original data sequence x (t), and fitting by using a cubic spline interpolation function to form an upper envelope line of the original data;
finding out all minimum value points, and fitting all the minimum value points through a cubic spline interpolation function to form a lower envelope curve of the data;
taking the mean value of the upper envelope and the lower envelope as c1, and subtracting the average value c1 from x (t) to obtain a new data sequence r 1;
x(t)-c1＝r1
if new data after the envelope averaging is subtracted from the original data, and if negative local maxima and positive local minima exist, which indicates that the new data is not an eigenmode function, the method needs to continue to carry out the 'screening', then r1 is decomposed again, r1-c2 is r2,
at this time, x (t) ═ c1+ c2+ r2
By analogy in sequence, can obtain
The EMD self-adaptive decomposition process can directly call an EMD module in matlab software to calculate;
decomposing the mixture to obtain n CjAfter the components, each C is calculated separatelyjSelecting two C with the highest kurtosis value and the second highest kurtosis valuejPerforming linear superposition to obtain a current signal of the characteristic highlight after EMD noise reduction, and then averagely dividing the obtained current signal of the characteristic highlight into m sections according to the time length, and recording the m sections as S1-Sm; the time value of each m section is not less than the time length of one period of the engine cycle work;
extracting a current wave crest value Imax and a current wave trough value Imin from S1-Sm to obtain S1- [ Imax-0, Imin-0], S2- [ Imax-0, Imin-0] … … Sm- [ Imax-0, Imin-0], and storing data into a database;
b. the test engine is replaced by a fault engine, and the number, position and degree of faults in the fault engine are arranged and combined to obtain n fault engines in different states and needing to be tested; repeating the steps a to c for each faulty engine in the permutation and combination mode, obtaining data S1- [ Imax-1, Imin-1], S2- [ Imax-1, Imin-1] … … Sm- [ Imax-1, Imin-1] by the faulty engine in the first permutation and combination mode, and the like, obtaining data S1- [ Imax-n, Imin-n ], S2- [ Imax-n, Imin-n ] … … Sm- [ Imax-n, Imin-n ] by the faulty engine in the nth permutation and combination mode; and storing the data into a database;
c. replacing the failed engine with an engine to be tested, and repeating the steps a to c to obtain S1- [ Imax-x, Imin-x ], S2- [ Imax-x, Imin-x ] … … Sm- [ Imax-x, Imin-x ];
d. defining the absolute value of subtraction between Imax-x in the S1 th engine to be tested and Imax-0 in the S1 corresponding to the database as delta max-0, and defining the absolute value of subtraction between Imin-x in the S1 th engine to be tested and Imin-0 in the S1 corresponding to the database as delta min-0; then calculated as follows:
replacing S1 with S2 … … Sm to give Δ 2 … … Δ m;
g. d, calculating the delta 1-delta m obtained in the step d according to the following formula:
d, sequentially replacing [ Imax-0 and Imin-0] in the step d with [ Imax-1 and Imin-1] … … [ Imax-n and Imin-n ], and repeating the steps to obtain mu 1 … … mu n; taking the minimum value mu-min in mu 0-mu n, and marking the state of the fault engine corresponding to mu-min as the state of the engine to be tested;
and finishing the diagnosis.
Examples of the above diagnostic method are as follows:
example one
Selecting a Jetta 2016 type automatic transmission car, wherein the engine type is EA113, the engine displacement is 1.6L, the four cylinders are arranged in a straight line, and internal parts of the engine are in a normal state; removing 4 spark plugs, installing a light source assembly at an inlet in front of a throttle valve, and then performing steps a to c, wherein the ignition duration is 4 s; when the rotation speed r of the engine is 120/min at 0.5, the data acquisition is started after 0.5s, the data acquisition time is 3s, the current signals acquired by the photoelectric sensor 22 are averagely divided into 5 sections according to the time period, the total time length of the current signals is 3s, and the time length of each section of signals is 0.6 s; obtaining [ Imax-0, Imin-0] of the S1-S5 section;
step b: four pistons in the test engine are replaced by fault pistons, the fault degree is mild in carbon deposition, and all air valves and air cylinder bodies are normal; the replaced fault engine is installed back to the original vehicle to obtain [ Imax-1, Imin-1] of the S1-S5 section;
four pistons in the test engine are replaced by fault pistons, the fault degree is moderate in carbon deposition, and all the air valves and the air cylinder bodies are normal; the replaced fault engine is installed back to the original vehicle to obtain [ Imax-2, Imin-2] of the S1-S5 section;
replacing four pistons in the test engine with fault pistons, wherein the fault degree is moderate carbon deposition, all inlet valves are replaced with fault valves, and the fault degree is moderate carbon deposition; the replaced fault engine is installed back to the original vehicle to obtain [ Imax-3, Imin-3] of the S1-S5 section;
and c, performing the step: replacing an automobile with the same engine type and the same vehicle type again, wherein the automobile has the driving mileage of 2.5 kilometers, and the engine fault does not occur; taking the vehicle engine as an engine to be tested to obtain [ Imax-x, Imin-x ] of S1-S5 sections; data results are shown in table 1.
The sections S1-S5 in Table 1 correspond to Imax and Imin under different faults respectively
| [Imax-0,Imin-0] | [Imax-1,Imin-1] | [Imax-2,Imin-2] | [Imax-3,Imin-3] | [Imax-x,Imin-x] | |
| S1 | [27.85,8.44] | [24.05，7.25] | [23.02,6.86] | [21.05,5.45] | [26.88,7.05] |
| S2 | [25.65,8.41] | [25.15,7.11] | [23.14,6.98] | [21.54,5.87] | [26.45,7.03] |
| S3 | [27.15,8.01] | [23.78,7.55] | [23.20,6.87] | [21.87,5.45] | [29.01,7.85] |
| S4 | [26.58,7.97] | [25.85,7.02] | [22.74,6.76] | [21.64,5.34] | [25.45,6.97] |
| S5 | [24.38,6.96] | [24.82,7.14] | [23.05,7.05] | [21.12,5.45] | [26.36,7.15] |
Then according to the data obtained in table 1, performing step d; the resulting parameters are shown in Table 2.
TABLE 2u value results
| μ0 | μ1 | μ2 | μ3 |
| 0.762 | 1.120 | 1.562 | 2.344 |
According to table 2, μ 0 is the smallest, so that the fault degree of the automobile [ Imax-x, Imin-x ] to be tested is consistent with the engine state corresponding to [ Imax-1, Imin-1], that is, the engine is normal, the automobile engine is disassembled after the diagnosis of the condition without carbon deposition, the surfaces of the valve and the cylinder block in the combustion chamber of the automobile engine are bright, the peripheries of the top ends of the pistons of the 1 cylinder and the 3 cylinder are slightly carbon deposited, it can also be explained that μ 0 is closer to μ 1 in the diagnosis data, and meanwhile, the calculation result is consistent with the actual condition.
According to the process, an accurate database of the degree of carbon deposition in the engine cylinder is established in advance, and during subsequent use, the carbon deposition condition in each cylinder combustion chamber of the engine can be accurately diagnosed only by measuring the engine to be tested and comparing the measured engine with the database data, so that corresponding maintenance strategies are worked out, for example, light carbon deposition and medium carbon deposition can be removed by using an additive combustion mode, and heavy carbon deposition needs to be removed by disassembling the engine for cleaning and repairing.
The method has the advantages that different current signals are obtained to judge the carbon deposition degree of the engine combustion chamber by utilizing the fact that the reflected and diffused light rays irradiated inside the engine combustion chamber have different intensities when the carbon deposition degree in the engine combustion chamber is different, the judging process is rapid, fewer disassembled parts are needed, the diagnosis time period is short, and the flow is simple; as long as the number of fault models in the database is enough, the diagnosis efficiency is high, EMD noise reduction processing is performed before comparison of current signals, the signal precision is better, a double-limit error comparison effect is adopted during comparison of the current signals, namely, the maximum value and the minimum value are respectively compared, and two comparison results are processed by a mathematical method, so that the accuracy of the comparison results is high, even if the result measured in a certain Sm time period is not accurate enough, for example, the maximum value of S3- [ Imax-x, Imin-x ] data in the experiment is slightly larger than that in other time periods, the data results are still correct after multi-section comparison and proper combination processing of the comparison errors are adopted, and therefore, the diagnosis accuracy is also high.
In the actual diagnosis process, the rotating speed of the engine in the data acquisition time period fluctuates, and the rotating speed in each test cannot be completely equal, but the diagnosis method segments the data, and detects the maximum value and the minimum value of the circuit in each segment, so that the fluctuation of the rotating speed only influences the current fluctuation frequency in the segment, the influence on the peak value and the trough value of the current is almost zero, and the fluctuation can be ignored, therefore, the diagnosis method has better practical application value, and the accuracy of the calculation result can be higher as long as the ignition duration is long enough during diagnosis; the requirements on diagnostic personnel are not high, and ordinary maintenance personnel and even automobile drivers can easily master the use method.
In addition, it should be noted that some automobile engines are embedded with cylinder sleeves in detachable cylinder bodies, so that the replacement is convenient, if the cylinder bodies of the engines are not detachable, the cylinder bodies need to be ground in a test engine firstly, and then the cylinder bodies are put into the cylinder sleeves with corresponding sizes for training, and the two types of engines can be directly diagnosed.
According to the convenient method for rapidly diagnosing the degree of carbon deposition in the combustion chamber of the engine, the corresponding diagnosis device comprises a light source assembly and a photoelectric receiving assembly, the light source assembly comprises a plug rod 11 with the shape consistent with that of a spark plug of the engine, an external thread is arranged on the outer side surface of one end of the plug rod 11, so that the plug rod 11 can be installed on a spark plug seat of an engine cylinder cover, the other end of the plug rod 11 is connected with an electric push rod 12 through a bolt or a buckle, an extension rod of the electric push rod 12 penetrates into a through hole axially arranged along the plug rod 11, and an LED lamp 13 is adhered or welded at the end of the extension rod of; the photoelectric receiving assembly comprises a hollow cylindrical support 21, and the outer side of the support 21 is provided with a thread matched with a spark plug seat; a photoelectric sensor 22 is arranged in a middle through hole of the support 21 and can be bonded or connected in a buckling mode; the end of the photoelectric sensor 22 extends out of the support 21 and enters the combustion chamber; the signal wire of the photoelectric sensor 22 extends out of the support 21 and is in communication connection with the microcomputer 24 through the A/D conversion module; the microcomputer 24 is also in communication connection with the control lines of the electric push rod 12 and the LED lamp 13 respectively; the microcomputer is also in communication connection with an OBD diagnosis interface installed on the automobile through an OBD special data line and reads the rotating speed of the engine in real time; the power lines of the microcomputer 24, the electric push rod 12 and the LED lamp 13 are respectively connected with the battery 14.
The battery 14 is a long lithium battery or a cylindrical lithium battery, the LED lamp 13 is a circular or regular polygonal lamp group formed by arranging a plurality of LED lamp beads on the mounting base plate, or one LED lamp bead, and a circular or regular polygonal lampshade is arranged outside the lamp beads. The LED lamp 13 can be a BMS-G4G9LED lamp bead of Bomingshi, or a TELESKY1206LED lamp, or can be a high-brightness LED illuminating lamp bead or lamp post of other types; the electric push rod 12 and the LED lamp 13 can also be connected with a storage battery carried by the automobile or a storage battery carried by the automobile;
the photoelectric sensor 22 is a phototriode or a photodiode, the model can be an E18-D80NK photoelectric sensor module, or a ZH-E3K-DJ7M1 direct current 10-30VDC photoelectric sensor, or other models, the A/D conversion module 23 can be a Jenton D-150-M2 model, or a world communication ADC0832CCNDIP-8/8 bit resolution/dual-channel A/D module, or other models; the microcomputer 24 can be a small computer host for the research IBOX-208 type industry, can also be a Siemens/PLC/6 ES7288-1SR20 host, and can also be an at89c51-24pi type singlechip; the electric push rod can be a CNXCI direct current electric push rod XC860, a Wxtg constant force electric push rod, or other types;
when the sensor, the electric push rod and other electronic equipment are selected and the microcomputer is selected, communication connection can be carried out according to the specifications or connection diagrams of related products.
Claims (1)
1. The method for quickly diagnosing the carbon deposition degree of the engine combustion chamber is convenient to use, firstly, one or more engines which can be normally used and have complete parts are defined as test engines, the surfaces of air valves, the inner side wall of an air cylinder body and the upper surface of a piston in the test engines are in a normal state without carbon deposition, and the engines can be normally started; the test engine is normally installed on the corresponding type of automobile;
then replacing the normal state valve or cylinder block or piston of one or more positions in the test engine with a fault state valve or fault state cylinder block or fault state piston, wherein the engine is defined as a fault engine; the failure state is that carbon deposition is adhered on the surfaces of the valve, the cylinder body or the piston respectively; according to the adhesion degree of the carbon deposit, the fault states are classified into mild, moderate and severe; after the replacement is finished, the fault engine is normally installed on the automobile with the corresponding model;
defining an engine with unknown state to be diagnosed as an engine to be detected, wherein the engine to be detected is directly installed on a vehicle to be diagnosed and is not detached;
according to a convenient method for rapidly diagnosing the degree of carbon deposition in an engine combustion chamber, a corresponding diagnosis device comprises a light source assembly and a photoelectric receiving assembly, wherein the light source assembly comprises a plug rod (11) with the shape consistent with that of an engine spark plug, an external thread is arranged on the outer side surface of one end of the plug rod (11), so that the plug rod (11) can be arranged on a spark plug seat of an engine cylinder cover, the other end of the plug rod (11) is connected with an electric push rod (12) through a bolt or a buckle, an extension rod of the electric push rod (12) penetrates through a through hole axially arranged along the plug rod (11), and the end of the extension rod of the electric push rod (12) is adhered or welded with an LED lamp; the photoelectric receiving assembly comprises a hollow cylindrical support (21), and the outer side of the support (21) is provided with a thread matched with a spark plug seat; a photoelectric sensor (22) is arranged in a middle through hole of the support (21); the end of the photoelectric sensor (22) extends out of the support (21) and enters the combustion chamber;
the rapid diagnosis method comprises the following steps: firstly, placing an automobile transmission provided with a test engine in a neutral gear; removing all spark plugs on a cylinder cover of the test engine, mounting a photoelectric receiving assembly on one spark plug seat, and mounting a corresponding number of light source assemblies on the remaining one or more spark plugs; a bolt with the same specification as the thread of the spark plug is arranged on the spark plug seat which is not provided with the photoelectric receiving assembly or the light source assembly; then the following steps are carried out in sequence:
a. turning on an LED lamp in the light source component; igniting by using an automobile key or a key starting button for a period of time, wherein the spark plug is detached, and the engine is driven by the starting motor to rotate at a low speed; the piston in the combustion chamber moves up and down, and the intake valve and the exhaust valve are opened or closed periodically, and the light of the LED lamp positioned in the combustion chamber is transmitted to the vicinity of the photoelectric receiving component in a reflection or diffusion mode in the combustion chamber; when the rotating speed r of the engine exceeds a certain value r1, a photoelectric sensor in the photoelectric receiving assembly starts to receive light illumination to form a current signal, the current signal is sent to the microcomputer through the A/D conversion module, and the signal receiving is stopped after a certain time T;
b. the test engine is replaced by a fault engine, and the number, position and degree of faults in the fault engine are arranged and combined to obtain n fault engines in different states and needing to be tested; repeating the step a for each faulty engine in the permutation and combination mode;
c. replacing the failed engine with the engine to be tested, and repeating the step a;
d. and c, comparing the data obtained in the step c with the data obtained in the step a and the step b, and defining the engine state with the closest comparison result as the state of the engine to be tested.
The method is characterized in that: in the step a, the microcomputer takes the collected current signal as a training sample, and EMD self-adaptive decomposition is carried out on the current signal x (t) in the training sample, wherein the decomposition method comprises the following steps:
in the above formula, n is the number of decomposed IMF components; cjRepresents the jth IMF component, j 1,2,3.., n; r isnIs the residual component;
decomposing the mixture to obtain n CjAfter the components, each C is calculated separatelyjSelecting two C with the highest kurtosis value and the second highest kurtosis valuejPerforming linear superposition to obtain a current signal of the characteristic highlight after EMD noise reduction, and then averagely dividing the obtained current signal of the characteristic highlight into m sections according to the time length, and recording the m sections as S1-Sm;
extracting a current wave crest value Imax and a current wave trough value Imin from S1-Sm to obtain S1- [ Imax-0, Imin-0], S2- [ Imax-0, Imin-0] … … Sm- [ Imax-0, Imin-0], and storing data into a database;
in the step b, the faulty engine in the first permutation and combination mode obtains data S1- [ Imax-1, Imin-1], S2- [ Imax-1, Imin-1] … … Sm- [ Imax-1, Imin-1], and so on, and the faulty engine in the nth permutation and combination mode obtains data S1- [ Imax-n, Imin-n ], S2- [ Imax-n, Imin-n ] … … Sm- [ Imax-n, Imin-n ]; and storing the data into a database;
in the step c, data S1- [ Imax-x, Imin-x ], S2- [ Imax-x, Imin-x ] … … Sm- [ Imax-x, Imin-x ] obtained by the engine to be tested;
in the step d, comparing the [ Imax-x and Imin-x ] with the [ Imax-0 and Imin-0] … … [ Imax-n and Imin-n ] respectively; defining the absolute value of subtraction between Imax-x in the S1 th engine to be tested and Imax-0 in the S1 corresponding to the database as delta max-0, and defining the absolute value of subtraction between Imin-x in the S1 th engine to be tested and Imin-0 in the S1 corresponding to the database as delta min-0; then calculated as follows:
replacing S1 with S2 … … Sm to give Δ 2 … … Δ m;
d, calculating the delta 1-delta m obtained in the step d according to the following formula:
sequentially replacing [ Imax-0 and Imin-0] in the step d with [ Imax-1 and Imin-1] … … [ Imax-n and Imin-n ], and repeating the steps to obtain mu 1 … … mu n; and taking the minimum value mu-min in mu 0-mu n, and marking the state of the engine corresponding to the mu-min as the state of the engine to be tested.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011421026.5A CN112683540B (en) | 2019-06-13 | 2019-06-13 | Method for quickly diagnosing carbon deposition degree of engine combustion chamber with convenient use |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910519095.0A CN110231174B (en) | 2019-06-13 | 2019-06-13 | Method for rapidly diagnosing carbon deposition degree of engine combustion chamber |
| CN202011421026.5A CN112683540B (en) | 2019-06-13 | 2019-06-13 | Method for quickly diagnosing carbon deposition degree of engine combustion chamber with convenient use |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910519095.0A Division CN110231174B (en) | 2019-06-13 | 2019-06-13 | Method for rapidly diagnosing carbon deposition degree of engine combustion chamber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112683540A true CN112683540A (en) | 2021-04-20 |
| CN112683540B CN112683540B (en) | 2023-01-06 |
Family
ID=67859314
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910519095.0A Active CN110231174B (en) | 2019-06-13 | 2019-06-13 | Method for rapidly diagnosing carbon deposition degree of engine combustion chamber |
| CN202011421026.5A Active CN112683540B (en) | 2019-06-13 | 2019-06-13 | Method for quickly diagnosing carbon deposition degree of engine combustion chamber with convenient use |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910519095.0A Active CN110231174B (en) | 2019-06-13 | 2019-06-13 | Method for rapidly diagnosing carbon deposition degree of engine combustion chamber |
Country Status (1)
| Country | Link |
|---|---|
| CN (2) | CN110231174B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110231174B (en) * | 2019-06-13 | 2021-02-23 | 西华大学 | Method for rapidly diagnosing carbon deposition degree of engine combustion chamber |
| CN112611573B (en) * | 2020-11-30 | 2022-06-07 | 重庆长安汽车股份有限公司 | Test method for carbon deposition rack of spark plug of whole vehicle engine |
| CN112819783B (en) * | 2021-01-30 | 2022-05-17 | 同济大学 | Method and device for identifying carbon deposits in engine cylinders based on image background difference |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1122541A (en) * | 1997-07-04 | 1999-01-26 | Nissan Motor Co Ltd | Direct-injection-type internal combustion engine |
| JPH1150941A (en) * | 1997-07-31 | 1999-02-23 | Toyota Motor Corp | Ignition plug diagnostic device of internal combustion engine |
| US20050022776A1 (en) * | 2003-08-01 | 2005-02-03 | Montgomery David T. | System and method to detect and correct spark plug fouling in a marine engine |
| CN202916096U (en) * | 2012-09-25 | 2013-05-01 | 浙江吉利汽车研究院有限公司杭州分公司 | Engine carbon deposit detection device |
| JP2014190308A (en) * | 2013-03-28 | 2014-10-06 | Daihatsu Motor Co Ltd | Device for controlling spark ignition-type internal combustion engine |
| CN104541144A (en) * | 2012-06-22 | 2015-04-22 | 伊利诺斯工具制品有限公司 | System and method for analyzing carbon build up in an engine |
| CN104728020A (en) * | 2013-12-19 | 2015-06-24 | 福特环球技术公司 | Spark plug fouling detection for ignition system |
| CN104728021A (en) * | 2013-12-19 | 2015-06-24 | 福特环球技术公司 | Spark plug fouling detection for ignition system |
| CN106321239A (en) * | 2015-06-30 | 2017-01-11 | 福特环球技术公司 | Method and system for detection of hot spark plug fouling |
| CN208467579U (en) * | 2018-07-11 | 2019-02-05 | 南京工程学院 | Soldering tip detection device |
| CN110231174B (en) * | 2019-06-13 | 2021-02-23 | 西华大学 | Method for rapidly diagnosing carbon deposition degree of engine combustion chamber |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102359881A (en) * | 2011-07-07 | 2012-02-22 | 深圳市王冠汽车用品有限公司 | Engine detector |
| CN106018225B (en) * | 2016-06-28 | 2019-01-18 | 浙江大学 | A kind of DPF accurate reproduction method and apparatus based on laser detection PM concentration |
| CN108152041A (en) * | 2017-12-26 | 2018-06-12 | 潍柴动力股份有限公司 | A kind of carbon distribution model experiment condition control method and device |
| CN110159428B (en) * | 2019-06-05 | 2024-03-12 | 西华大学 | Diagnostic device and method for carbon deposition in engine cylinder |
| CN210152786U (en) * | 2019-06-05 | 2020-03-17 | 西华大学 | Diagnosis device for carbon deposition in engine cylinder |
-
2019
- 2019-06-13 CN CN201910519095.0A patent/CN110231174B/en active Active
- 2019-06-13 CN CN202011421026.5A patent/CN112683540B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1122541A (en) * | 1997-07-04 | 1999-01-26 | Nissan Motor Co Ltd | Direct-injection-type internal combustion engine |
| JPH1150941A (en) * | 1997-07-31 | 1999-02-23 | Toyota Motor Corp | Ignition plug diagnostic device of internal combustion engine |
| US20050022776A1 (en) * | 2003-08-01 | 2005-02-03 | Montgomery David T. | System and method to detect and correct spark plug fouling in a marine engine |
| CN104541144A (en) * | 2012-06-22 | 2015-04-22 | 伊利诺斯工具制品有限公司 | System and method for analyzing carbon build up in an engine |
| CN202916096U (en) * | 2012-09-25 | 2013-05-01 | 浙江吉利汽车研究院有限公司杭州分公司 | Engine carbon deposit detection device |
| JP2014190308A (en) * | 2013-03-28 | 2014-10-06 | Daihatsu Motor Co Ltd | Device for controlling spark ignition-type internal combustion engine |
| CN104728020A (en) * | 2013-12-19 | 2015-06-24 | 福特环球技术公司 | Spark plug fouling detection for ignition system |
| CN104728021A (en) * | 2013-12-19 | 2015-06-24 | 福特环球技术公司 | Spark plug fouling detection for ignition system |
| CN106321239A (en) * | 2015-06-30 | 2017-01-11 | 福特环球技术公司 | Method and system for detection of hot spark plug fouling |
| CN208467579U (en) * | 2018-07-11 | 2019-02-05 | 南京工程学院 | Soldering tip detection device |
| CN110231174B (en) * | 2019-06-13 | 2021-02-23 | 西华大学 | Method for rapidly diagnosing carbon deposition degree of engine combustion chamber |
Non-Patent Citations (2)
| Title |
|---|
| 刘威: ""发动机的积碳及对汽车性能的影响"", 《北京劳动保障职业学院学报》 * |
| 熊震: ""发动机积碳的诊断和清除方法"", 《机械研究与应用》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112683540B (en) | 2023-01-06 |
| CN110231174A (en) | 2019-09-13 |
| CN110231174B (en) | 2021-02-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110231174B (en) | Method for rapidly diagnosing carbon deposition degree of engine combustion chamber | |
| CN106227200A (en) | A kind of automobile on-line fault diagnosis method | |
| DE102019100042A1 (en) | SYSTEMS AND METHOD FOR CYLINDER OUTLET VALVE DIAGNOSIS | |
| CN104919298B (en) | Explosive motor based on exhaust manifold pressure misfires detection | |
| WO2011018292A1 (en) | Method and device for adapting and/or diagnosing an internal combustion engine disposed in a hybrid vehicle | |
| DE102017220190A1 (en) | Method and device for diagnosing a crankcase ventilation line for an internal combustion engine | |
| CN210152786U (en) | Diagnosis device for carbon deposition in engine cylinder | |
| CN110159428B (en) | Diagnostic device and method for carbon deposition in engine cylinder | |
| LU502777B1 (en) | Intelligent diagnosis and treatment method and system for tail gas of motor vehicle | |
| CN209894488U (en) | Device for rapidly diagnosing carbon deposition degree of engine combustion chamber | |
| CN109404157B (en) | Engine flywheel housing observation window and turning method | |
| Czech | Diagnosing faults in the timing system of a passenger car spark ignition engine using the Bayes classifier and entropy of vibration signals | |
| KR101430399B1 (en) | Engine Analysis Apparatus Using Oxygen Sensor | |
| US11661868B2 (en) | Systems and methods for hole detection in crankcase ventilation tubing | |
| Guinther et al. | Formation of intake valve deposits in gasoline direct injection engines | |
| RU2374613C2 (en) | Method to diagnose ice valve gear and device to this end | |
| Tucki et al. | Analysis of the possibility of using neural networks to monitor the technical efficiency of diesel engines during operation | |
| ATE538292T1 (en) | METHOD FOR DIAGNOSING FAILURE OF AN EXHAUST LINE FILTER OF AN INTERNAL COMBUSTION ENGINE | |
| CN114718723B (en) | Method for diagnosing engine oil burning on vehicle | |
| Chander et al. | The effect of different intake air filters on DI diesel engine combustion and its exhaust characteristics | |
| RU2820020C1 (en) | Device for evaluation of technical condition and detection of incipient faults in systems and mechanisms of engine | |
| CN113323759B (en) | Method for controlling internal working condition of engine based on priority | |
| Vrublevskyi et al. | Precision diagnostics of a diesel engine under agricultural tractor operating conditions | |
| RU193821U1 (en) | INSTALLATION FOR EXPRESS DIAGNOSTICS OF DIESELS | |
| Stanik et al. | Application of vibration signals in the diagnosis of combustion engines-exploitation practices |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20221214 Address after: Floor 3, Building 2, Electronic and Information Products Logistics Functional Zone, Plot A4-6-1, Export Processing Zone, Economic Development Zone, Kunming Pilot Free Trade Zone, 650000 Yunnan Province Applicant after: Yunnan Xinhang Zhicheng Technology Co.,Ltd. Address before: Xihua University, 999 Jinzhou Road, Jinniu District, Chengdu, Sichuan 610039 Applicant before: XIHUA University |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |