CN109281759B - System and method for diagnosing leakage of oil tank by adopting pressure sensor - Google Patents
System and method for diagnosing leakage of oil tank by adopting pressure sensor Download PDFInfo
- Publication number
- CN109281759B CN109281759B CN201811026654.6A CN201811026654A CN109281759B CN 109281759 B CN109281759 B CN 109281759B CN 201811026654 A CN201811026654 A CN 201811026654A CN 109281759 B CN109281759 B CN 109281759B
- Authority
- CN
- China
- Prior art keywords
- oil tank
- tank
- vacuum degree
- pressure
- leakage
- 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.)
- Active
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B77/00—Component parts, details or accessories, not otherwise provided for
- F02B77/08—Safety, indicating or supervising devices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M25/00—Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel or fuel-air mixture
- F02M25/08—Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel or fuel-air mixture adding fuel vapours drawn from engine fuel reservoir
- F02M25/0809—Judging failure of purge control system
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/40—Engine management systems
Abstract
The invention provides a system and a method for diagnosing oil tank leakage by adopting a pressure sensor, belonging to the technical field of detection. The method solves the defect of how to effectively reduce the application of the method for diagnosing the leakage of the oil tank by using the pressure sensor on starting and stopping vehicles. The system for diagnosing the leakage of the oil tank by adopting the pressure sensor comprises a vacuum degree establishing module, a vacuum degree maintaining module, a waiting module, an attenuation gradient measuring module and a judging module. The method is characterized in that closed-loop control is carried out on the target vacuum degree of the oil tank by establishing the target vacuum degree, and the target vacuum degree of the oil tank is maintained; keeping the target vacuum degree to wait for the vehicle speed to be lower than the vehicle speed threshold or the engine to enter a start-stop state; and measuring the vacuum attenuation gradient of the oil tank and judging the leakage result. The system is split according to the influence degree of pressure fluctuation noise of the oil tank and the specific requirement on the working condition of the engine in the oil tank leakage diagnosis process, so that the oil tank leakage diagnosis can be carried out on a start-stop function vehicle model under the condition of not interfering the start-stop function.
Description
Technical Field
The invention belongs to the technical field of detection, and relates to a system and a method for diagnosing oil tank leakage by adopting a pressure sensor.
Background
One of the most cost-effective methods in the existing leakage diagnosis schemes for the evaporation system is a method for diagnosing the leakage of the oil tank by using an oil tank pressure sensor mounted on the oil tank or the pipeline, and the method for diagnosing the leakage of the oil tank by using the pressure sensor evaluates the leakage amount by monitoring the change of the oil tank pressure, and can diagnose whether the evaporation system has the leakage of 0.5mm or more than 0.1 mm. As shown in fig. 6, an intake manifold on the existing engine is connected with a canister through a canister desorption valve pipeline, the canister is connected with an oil tank pipeline, an oil tank pressure sensor is arranged on the oil tank, the canister is connected with a space through a canister vent valve pipeline, the canister desorption valve, the canister vent valve and the oil tank pressure sensor are in electrical signal connection with an engine management system, the existing structurally practical diagnosis method depends on a pressure signal measured by the pressure sensor, and the noise degree requirement on the pressure signal is high, so that the vehicle is basically required to be in a static state during diagnosis; in addition, some solutions that employ pressure sensors also place demands on the operating conditions of the engine. Therefore, the method using the pressure sensor is not perfectly suitable for some vehicles, such as start-stop vehicles, hybrid vehicles, etc., and if applied forcibly, conditions are sacrificed, which may be unacceptable in some vehicle models, such as sacrificing the number of start-stop times of the start-stop vehicle for diagnosis or forcibly starting the engine of the hybrid vehicle, which may affect fuel economy, also may degrade the driving experience of the end user, etc. The existing method for diagnosing the leakage of the oil tank by adopting the pressure sensor has the defects, so that the method is not suitable for vehicles with start-stop functions.
Chinese patent document discloses a tank leak device of application No. 201610953369.3 for diagnosing a fuel tank in a motor vehicle, the fuel tank being connected to an intake system of an internal combustion engine via a ventilation pipe, the internal combustion engine being pressurizable by means of a supercharger, the fuel tank being loadable with compressed air by means of a pressure generated in the supercharger, a valve being arranged in the ventilation pipe, via which the fuel tank is loadable with compressed air, the valve being closable after the pressure loading so that the ventilation pipe is shut off, in which device the fuel tank is loaded with compressed air and a leak of the fuel tank is inferred from the pressure drop. Although the method for diagnosing the fuel tank leakage using the positive pressure enables cost reduction and a simple structure, the method has the same problems as those of the prior art and is not suitable for use in start and stop vehicles.
Disclosure of Invention
The present invention addresses the above-identified problems of the prior art by providing a system and method for diagnosing fuel tank leakage using a pressure sensor. The method solves the defect that how to effectively reduce the application of the method for diagnosing the leakage of the oil tank by using the pressure sensor on starting and stopping vehicles.
The invention is realized by the following technical scheme: a system for diagnosing fuel tank leakage using a pressure sensor, comprising
The vacuum degree establishing module is used for closing the carbon tank desorption valve to enable the pressure of the oil tank to be recovered to the atmospheric pressure, then closing the carbon tank ventilation valve and opening the carbon tank desorption valve to establish the target vacuum degree of the oil tank by utilizing the vacuum of the air inlet manifold;
the vacuum degree maintaining module is used for restarting the carbon tank desorption valve when the vacuum degree of the oil tank is reduced and is smaller than a set value, and closing the carbon tank desorption valve until the target vacuum degree is close to the target vacuum degree in the circulating mode, so as to maintain the target vacuum degree of the oil tank;
the waiting module is used for keeping the target vacuum degree to wait that the vehicle speed is lower than a vehicle speed threshold or the engine enters a start-stop state;
the attenuation gradient measuring module is used for closing a carbon tank desorption valve when the current vehicle speed is lower than a threshold value or the engine enters a start-stop state, and an oil tank pressure sensor is used for measuring the vacuum attenuation gradient of the oil tank;
and the judgment module judges whether the oil tank leaks or not through the vacuum attenuation gradient of the oil tank.
The system comprises a vacuum degree establishing module, a vacuum degree maintaining module, a waiting module, an attenuation gradient measuring module and a judging module, wherein the vacuum degree establishing module closes a carbon tank desorption valve to recover the pressure of an oil tank to atmospheric pressure, then closes a carbon tank ventilation valve, opens the carbon tank desorption valve and establishes the target vacuum degree of the oil tank by utilizing the vacuum of an air inlet manifold, and after the target vacuum degree is established, the vacuum degree maintaining module performs closed-loop control by utilizing pressure data detected by an oil tank pressure sensor and the opening state of the carbon tank desorption valve to maintain the target vacuum degree of the oil tank. And in the process of keeping the target vacuum degree of the oil tank, the waiting module judges that the current speed of the vehicle is lower than a threshold value or the engine enters a start-stop state, the waiting module continuously waits for a set time, and the attenuation gradient measuring module closes the carbon tank desorption valve when the current speed of the vehicle is lower than the threshold value or the engine enters the start-stop state within the set time, and measures the vacuum attenuation gradient of the oil tank through the oil tank pressure sensor. The judgment module compares the detected vacuum attenuation gradient of the oil tank with a set gradient value, and judges that the oil tank leaks when the vacuum attenuation gradient of the oil tank is larger than the set gradient value. And if the vacuum attenuation gradient of the oil tank is less than or equal to the set gradient value, judging that the oil tank does not leak. The system utilizes the vacuum of the air inlet manifold to establish the vacuum degree inside the oil tank by regulating and controlling the carbon tank ventilation valve and the carbon tank desorption valve, and the measured vacuum attenuation gradient of the oil tank is used for judging the leakage condition of the automobile oil tank after the automobile enters a low automobile speed or an engine enters a start-stop state under the condition of keeping the target vacuum degree for a period of time. The system is divided into two parts according to the influence degree of oil tank pressure fluctuation noise in the oil tank leakage diagnosis process and the specific requirement on the working condition of the engine, and the system is divided into two parts: the vacuum establishing stage which is insensitive to pressure noise but has specific requirements on the working condition of the engine is completed in the early stage, the oil tank can quickly enter the second part under the condition of keeping the target vacuum degree of the oil tank, and the second part is the detection of the vacuum attenuation gradient which is sensitive to the pressure noise but has no requirements on the working condition of the engine, so that the oil tank leakage diagnosis can be carried out on the vehicle type with the start-stop function under the condition of not inhibiting the start-stop working condition.
In the system for diagnosing the leakage of the oil tank by adopting the pressure sensor, the system further comprises an evaporation speed measuring module, after the attenuation gradient measuring module carries out vacuum attenuation gradient measurement on the oil tank, the carbon tank vent valve is opened, the carbon tank vent valve is closed when the pressure of the oil tank is recovered to the standard atmospheric pressure, and at the moment, the data measured by the oil tank pressure sensor is the fuel evaporation speed. In order to evaluate the influence of fuel evaporation on the leakage diagnosis result, the evaporation rate measuring module is used for measuring the evaporation rate of the fuel, and the influence of other factors on the fuel evaporation rate in the vacuum attenuation gradient measuring process is reduced at the end of the detection close to the vacuum attenuation gradient measurement, so that the measured fuel evaporation rate is basically the same as the vacuum attenuation gradient measuring process, and the reliability of the leakage diagnosis result is improved.
In the system for diagnosing the leakage of the oil tank by adopting the pressure sensor, the system also comprises a correction module, wherein the vacuum attenuation gradient is used for subtracting the evaporation speed of the fuel oil to obtain a corrected attenuation gradient; and the judgment module judges that the oil tank leaks when the attenuation gradient after correction is larger than the set gradient value. The vacuum attenuation gradient is corrected through the fuel evaporation speed, so that the judged data are more accurate, the measurement of the evaporation speed is close to the measurement of the attenuation gradient, the influence of other factors on the fuel evaporation speed can be effectively reduced, and the judgment result of the fuel tank leakage is more reliable.
In the system for diagnosing the leakage of the oil tank by adopting the pressure sensor, the system further comprises a part diagnosis module for diagnosing parts in the process of establishing the target vacuum degree, when the carbon tank desorption valve is closed to enable the pressure of the oil tank to be recovered to the atmospheric pressure, if the pressure of the oil tank measured by the oil tank pressure sensor cannot be recovered to the atmospheric pressure, the normally closed fault of the carbon tank ventilation valve is judged, when the carbon tank ventilation valve is closed to enable the pressure reduction amount of the oil tank to exceed the pressure threshold value, the normally open fault of the carbon tank desorption valve is judged, when the pressure reduction amount of the oil tank does not exceed the pressure threshold value, the carbon tank desorption valve is opened, if the vacuum of the oil tank cannot be established, the normally closed fault of the carbon tank desorption valve is judged, and if the. The diagnosis process of the parts and the oil tank vacuum establishing process are not sensitive to pressure noise but have specific requirements on the working condition of the engine, so that the diagnosis process of the parts is put in the establishing process of the target vacuum degree of the oil tank, the diagnosis time is shortened, the establishment of the target vacuum degree of the oil tank is ensured, the final judgment of the attenuation gradient of the oil tank is not carried out when other parts have faults, and the oil tank leakage diagnosis is early exited. And making a fault diagnosis of the parts.
In the system for diagnosing the leakage of the oil tank by adopting the pressure sensor, the system also comprises an exit diagnosis module, wherein in the process of establishing the target vacuum degree, the oil tank leakage diagnosis is exited when any part is diagnosed to have a fault or large leakage, and the oil tank leakage diagnosis is exited when the target vacuum degree is maintained and the vehicle speed is lower than the vehicle speed threshold or the time of the engine entering the start-stop state exceeds the set time threshold. When the parts are diagnosed to be in fault or the target vacuum waiting time is too long, the oil tank leakage diagnosis can be timely quitted, and the oil tank leakage diagnosis can be timely made while the start-stop working condition of the engine is not influenced.
A method for diagnosing fuel tank leakage by using a pressure sensor,
establishing a target vacuum degree: closing the carbon tank desorption valve to restore the pressure of the oil tank to atmospheric pressure, then closing the carbon tank ventilation valve, opening the carbon tank desorption valve, and establishing the target vacuum degree of the oil tank by utilizing the vacuum of the air inlet manifold;
and (3) carrying out closed-loop control on the target vacuum degree of the oil tank: when the vacuum degree of the oil tank is smaller than a set value, the carbon tank desorption valve is opened again until the vacuum degree is close to the target vacuum degree, the carbon tank desorption valve is closed, and the circulation is performed so as to maintain the target vacuum degree of the oil tank; keeping the target vacuum degree to wait for the vehicle speed to be lower than the vehicle speed threshold or the engine to enter a start-stop state;
measuring the vacuum attenuation gradient of the oil tank and judging the leakage result: when the current vehicle speed is lower than a threshold value or the engine enters a start-stop state, the carbon tank desorption valve is closed, the oil tank pressure sensor measures the vacuum attenuation gradient of the oil tank, and whether the oil tank leaks or not is judged through the vacuum attenuation gradient of the oil tank.
According to the method, the pressure of the oil tank is recovered to the atmospheric pressure by closing the carbon tank desorption valve, then the carbon tank ventilation valve is closed, the carbon tank desorption valve is opened, the target vacuum degree of the oil tank is established by utilizing the vacuum of the air inlet manifold, after the target vacuum degree is established, closed-loop control is carried out by utilizing pressure data detected by the oil tank pressure sensor and the opening state of the carbon tank desorption valve, and the target vacuum degree of the oil tank is maintained. And in the process of maintaining the target vacuum degree of the oil tank, when the current speed of the vehicle is judged to be lower than the threshold value or the engine enters a start-stop state, the carbon tank desorption valve is closed, and the vacuum attenuation gradient of the oil tank is measured through the oil tank pressure sensor. And comparing the detected vacuum attenuation gradient of the oil tank with a set gradient value, and judging that the oil tank leaks when the vacuum attenuation gradient of the oil tank is greater than the set gradient value. And if the vacuum attenuation gradient of the oil tank is less than or equal to the set gradient value, judging that the oil tank does not leak. The invention utilizes the vacuum of the air inlet manifold to establish the vacuum degree in the oil tank by regulating and controlling the carbon tank ventilation valve and the carbon tank desorption valve, and the measured oil tank vacuum attenuation gradient is used for judging the leakage condition of the automobile oil tank after the automobile enters a low automobile speed or an engine enters a start-stop state under the condition of keeping the target vacuum degree for a period of time. The method is divided into two parts according to the influence degree of oil tank pressure fluctuation noise in the oil tank leakage diagnosis process and the specific requirement on the engine working condition, and the method comprises the following steps: the vacuum establishing stage which is insensitive to pressure noise but has specific requirements on the working condition of the engine is completed in the early stage, the oil tank can quickly enter the second part under the condition of keeping the target vacuum degree of the oil tank, and the second part is the detection of the vacuum attenuation gradient which is sensitive to the pressure noise but has no requirements on the working condition of the engine, so that the oil tank leakage diagnosis can be carried out on the vehicle type with the start-stop function under the condition of not inhibiting the start-stop working condition.
In the method for diagnosing the leakage of the oil tank by adopting the pressure sensor, after the vacuum attenuation gradient of the vacuum oil tank is measured, the carbon tank vent valve is opened, the carbon tank vent valve is closed when the pressure of the oil tank is recovered to the standard atmospheric pressure, the fuel evaporation speed is measured, the vacuum attenuation gradient subtracts the fuel evaporation speed to obtain the corrected attenuation gradient, and the leakage of the oil tank is judged when the corrected attenuation gradient is larger than the set gradient value. In order to evaluate the influence of fuel evaporation on the leakage diagnosis result, the evaporation rate measuring module is used for measuring the evaporation rate of the fuel, and the influence of other factors on the fuel evaporation rate in the vacuum attenuation gradient measuring process is reduced at the end of the detection close to the vacuum attenuation gradient measurement, so that the measured fuel evaporation rate is basically the same as the vacuum attenuation gradient measuring process, and the reliability of the leakage diagnosis result is improved. The vacuum attenuation gradient is corrected through the fuel evaporation speed, so that the judged data are more accurate, the measurement of the evaporation speed is close to the measurement of the attenuation gradient, the influence of other factors on the fuel evaporation speed can be effectively reduced, and the judgment result of the fuel tank leakage is more reliable.
In the method for diagnosing the leakage of the oil tank by adopting the pressure sensor, the part diagnosis is carried out in the process of establishing the target vacuum degree, and the normally closed fault of the carbon tank ventilation valve is judged if the pressure of the oil tank measured by the oil tank pressure sensor cannot be recovered to the atmospheric pressure when the pressure of the oil tank is recovered to the atmospheric pressure by closing the carbon tank desorption valve. The diagnosis process of the parts and the oil tank vacuum establishing process are not sensitive to pressure noise but have specific requirements on the working condition of the engine, so that the diagnosis process of the parts is put in the establishing process of the target vacuum degree of the oil tank, the diagnosis time is shortened, the establishment of the target vacuum degree of the oil tank is ensured, the final judgment of the attenuation gradient of the oil tank is not carried out when other parts have faults, and the oil tank leakage diagnosis is early exited. And making a fault diagnosis of the parts.
In the method for diagnosing the leakage of the oil tank by adopting the pressure sensor, the normally open fault of the carbon tank desorption valve is judged when the pressure drop of the oil tank exceeds the pressure threshold by closing the carbon tank ventilation valve, the carbon tank desorption valve is opened when the pressure drop of the oil tank does not exceed the pressure threshold, the normally closed fault of the carbon tank desorption valve is judged when the vacuum of the oil tank cannot be established, and the large leakage fault is judged when the vacuum of the oil tank can be established but cannot reach the target vacuum degree. The diagnosis process of the parts and the oil tank vacuum establishing process are not sensitive to pressure noise but have specific requirements on the working condition of the engine, so that the diagnosis process of the parts is put in the establishing process of the target vacuum degree of the oil tank, the diagnosis time is shortened, the establishing of the target vacuum degree of the oil tank is ensured, and the final judgment of the attenuation gradient of the oil tank cannot be carried out when other parts have faults. And when other parts are in fault, the final judgment of the oil tank attenuation gradient is not carried out. And early exiting the oil tank leakage diagnosis. And making a fault diagnosis of the parts.
In the method for diagnosing the leakage of the oil tank by adopting the pressure sensor, in the process of establishing the target vacuum degree, if any part is diagnosed to have a fault or large leakage, the oil tank leakage diagnosis is quitted. And when the part is diagnosed to have a fault, the oil tank leakage diagnosis can be timely quitted, and the oil tank leakage diagnosis can be timely made.
In the method for diagnosing the oil tank leakage by adopting the pressure sensor, the oil tank leakage diagnosis is quitted when the target vacuum degree is kept and the vehicle speed is lower than the vehicle speed threshold or the time of the engine entering the start-stop state exceeds the set time threshold. And when the target vacuum waiting time is too long, the oil tank leakage diagnosis can be timely quitted, and the influence on other functions is avoided.
Compared with the prior art, the system and the method for diagnosing the leakage of the oil tank by adopting the pressure sensor are provided. Has the following advantages:
1. the invention realizes the oil tank leakage diagnosis application on start-stop functional vehicles by adopting the oil tank pressure sensor through improving the control strategy on the basis of not changing the original oil tank pressure sensor, the carbon tank ventilation valve and the carbon tank desorption valve which are parts of the start-stop vehicles.
2. The invention splits the influence degree of the pressure fluctuation noise of the oil tank and the specific requirement on the working condition of the engine in the oil tank leakage diagnosis process, and divides the oil tank leakage diagnosis process into two parts: the vacuum establishing stage which is insensitive to pressure noise but has specific requirements on the working condition of the engine is completed in the early stage, the oil tank can quickly enter the second part under the condition of keeping the target vacuum degree of the oil tank, and the second part is the detection of the vacuum attenuation gradient which is sensitive to the pressure noise but has no requirements on the working condition of the engine, so that the oil tank leakage diagnosis can be carried out on the vehicle type with the start-stop function under the condition of not inhibiting the start-stop working condition.
3. According to the invention, the vacuum attenuation gradient is corrected through the fuel evaporation speed, so that the judged data is more accurate, the measurement of the evaporation speed is close to the measurement of the attenuation gradient, the influence of other factors on the fuel evaporation speed can be effectively reduced, and the judgment result of the fuel tank leakage is more reliable.
Drawings
FIG. 1 is a system block diagram of the present invention.
Fig. 2 is an overall flow chart of the present invention.
FIG. 3 is a flow chart of first stage component diagnostics and vacuum build-up.
FIG. 4 is a flow chart of the second stage of maintaining target vacuum, waiting for the vehicle to come to rest.
Fig. 5 is a third-stage leakage result measurement judgment flowchart.
Fig. 6 is a schematic pipeline diagram of an evaporation system on a start-stop function type vehicle.
In the figure, 1, a vacuum degree building module; 2. a vacuum degree maintaining module; 3. a waiting module; 4. an attenuation gradient measurement module; 5. a judgment module; 6. an evaporation rate measuring module; 7. a correction module; 8. a component diagnostic module; 9. and exiting the diagnosis module.
Detailed Description
The following are specific embodiments of the present invention, and the technical solutions of the present invention will be further described with reference to the drawings, but the present invention is not limited to these embodiments.
As shown in fig. 1-6, the system for diagnosing fuel tank leakage by using a pressure sensor is arranged in an engine management system, and comprises a vacuum degree establishing module 1, a canister vent valve, a canister desorption valve, a canister valve, a fuel tank pressure recovery module, a canister vent valve, a canister purge valve, a; the vacuum degree maintaining module 2 is used for restarting the carbon tank desorption valve when the vacuum degree of the oil tank is reduced and is smaller than a set value, and closing the carbon tank desorption valve until the target vacuum degree is close to the target vacuum degree, so that the cycle is repeated, and the target vacuum degree of the oil tank is maintained; the waiting module 3 is used for keeping the target vacuum degree to wait that the vehicle speed is lower than a vehicle speed threshold or the engine enters a start-stop state; the attenuation gradient measuring module 4 is used for closing a carbon tank desorption valve when the current vehicle speed is lower than a threshold value or the engine enters a start-stop state, and an oil tank pressure sensor is used for measuring the vacuum attenuation gradient of the oil tank; and the judgment module 5 judges whether the oil tank leaks or not through the vacuum attenuation gradient of the oil tank.
The system further comprises an evaporation speed measuring module 6 and a correction module 7, wherein after the attenuation gradient measuring module 4 carries out oil tank vacuum attenuation gradient measurement, the evaporation speed measuring module 6 opens a carbon tank ventilation valve, and closes the carbon tank ventilation valve when the pressure of the oil tank is recovered to the standard atmospheric pressure, and the data measured by the oil tank pressure sensor is the fuel evaporation speed. And the measured data of the tank pressure sensor in a period of time thereafter is the fuel evaporation rate. The correction module 7 subtracts the fuel evaporation speed from the vacuum attenuation gradient to obtain a corrected attenuation gradient; the judgment module 5 judges that the oil tank leaks when the attenuation gradient comparison after correction is larger than the set gradient value. In order to evaluate the influence of fuel evaporation on the leakage diagnosis result, the evaporation rate measuring module 6 is used for measuring the evaporation rate of the fuel, and the influence of other factors on the fuel evaporation rate in the vacuum attenuation gradient measuring process is reduced at the end of the vacuum attenuation gradient measurement, so that the measured fuel evaporation rate is basically the same as the vacuum attenuation gradient measuring process, and the reliability of the leakage diagnosis result is improved. Meanwhile, the vacuum attenuation gradient is corrected through the fuel evaporation speed, so that the judged data are more accurate, the measurement of the evaporation speed is close to the measurement of the attenuation gradient, the influence of other factors on the fuel evaporation speed can be effectively reduced, and the judgment result of the fuel tank leakage is more reliable. And exiting the fuel tank leakage diagnosis when the enabling condition is not met in the process of the leakage diagnosis.
This system still includes spare part diagnostic module 8 and withdraws from diagnostic module 9, spare part diagnostic module 8 is used for establishing the target vacuum in-process and carries out the spare part diagnosis, close at the carbon tank desorption valve and make the oil tank pressure resume atmospheric pressure when the oil tank pressure that oil tank pressure sensor measured can't resume atmospheric pressure then judge carbon tank ventilation valve normally closed fault, close when the carbon tank ventilation valve makes the oil tank pressure decline volume exceed the pressure threshold value then judge carbon tank desorption valve normally open fault, open the carbon tank desorption valve when the oil tank pressure decline volume does not exceed the pressure threshold value, oil tank vacuum can not establish then judge carbon tank desorption valve normally closed fault, the oil tank vacuum can establish but can not reach the target vacuum then judge for the gross leakage fault. In the process of establishing the target vacuum degree, if any part is diagnosed to have a fault or large leakage, the oil tank leakage diagnosis is quitted, and the target vacuum degree is maintained to wait for the vehicle speed to be lower than the vehicle speed threshold or the time of the engine entering the start-stop state to exceed the set time threshold, the oil tank leakage diagnosis is quitted. The diagnosis process of the parts and the oil tank vacuum establishing process are not sensitive to pressure noise but have specific requirements on the working condition of the engine, so that the diagnosis process of the parts is put in the establishing process of the target vacuum degree of the oil tank, the diagnosis time is shortened, the establishing of the target vacuum degree of the oil tank is ensured, and the final judgment of the attenuation gradient of the oil tank cannot be carried out when other parts have faults. And early exiting the oil tank leakage diagnosis. And making a fault diagnosis of the parts. The oil tank leakage diagnosis can be timely quitted when the fault is diagnosed by the parts or the target vacuum waiting time is too long, and the oil tank leakage diagnosis can be timely made while the start-stop working condition of the engine is not influenced.
The carbon tank is connected with the oil tank pipeline through a carbon tank desorption valve pipeline between an air inlet manifold on the existing start-stop function vehicle engine and the carbon tank, the oil tank is connected with the oil tank pipeline, an oil tank pressure sensor is arranged on the oil tank or the pipeline, the carbon tank is connected with the air inlet manifold through a carbon tank ventilation valve pipeline, and the carbon tank desorption valve, the carbon tank ventilation valve and the oil tank pressure sensor are in electric signal connection with an engine management system. The system for diagnosing the leakage of the oil tank by adopting the pressure sensor is arranged in an engine management system and is an application program system in the engine management system. The system comprises a vacuum degree establishing module 1, a vacuum degree maintaining module 2, a waiting module 3, an attenuation gradient measuring module 4, a judging module 5, an evaporation speed measuring module 6, a correcting module 7, a part diagnosing module 8 and a quitting diagnosing module 9. The vacuum degree establishment module 1 closes the carbon tank desorption valve to enable the pressure of the oil tank to recover to atmospheric pressure, then closes the carbon tank ventilation valve and opens the carbon tank desorption valve to establish the target vacuum degree of the oil tank by utilizing the vacuum of the air inlet manifold, the part diagnosis module 8 also works in the working process of the vacuum degree establishment module 1, and the conditions such as whether the carbon tank ventilation valve, the carbon tank desorption valve and the oil tank leak or not are analyzed and judged according to the pressure conditions of the oil tank, which are achieved through the opening and closing control of the carbon tank ventilation valve and the carbon tank desorption valve in the vacuum degree establishment process of the oil tank. After the target vacuum degree is established, the vacuum degree maintaining module 2 performs closed-loop control by using pressure data detected by the oil tank pressure sensor and the opening state of the carbon tank desorption valve to maintain the target vacuum degree of the oil tank. And in the process of keeping the target vacuum degree of the oil tank, the waiting module 3 judges that the current speed of the vehicle is lower than a threshold value or the engine enters a start-stop state, the waiting module continuously waits for set time, and the attenuation gradient measuring module 4 closes the carbon tank desorption valve when the current speed of the vehicle is lower than the threshold value or the engine enters the start-stop state within the set time, and measures the vacuum attenuation gradient of the oil tank through the oil tank pressure sensor. After the attenuation gradient measurement module 4 performs oil tank vacuum attenuation gradient measurement, the evaporation rate measurement module 6 controls to open the carbon tank vent valve, and closes the carbon tank vent valve when the pressure of the oil tank is recovered to the standard atmospheric pressure, and data measured by the oil tank pressure sensor is the fuel evaporation rate. And the measured data of the tank pressure sensor in a period of time thereafter is the fuel evaporation rate. Then the correction module 7 subtracts the fuel evaporation speed from the vacuum attenuation gradient to obtain a corrected attenuation gradient, and the judgment module 5 judges that the fuel tank leaks when the corrected attenuation gradient is larger than a set gradient value. And judging that the oil tank does not leak when the attenuation gradient after correction is less than or equal to the set gradient value. The system utilizes the vacuum of the air inlet manifold to establish the vacuum degree inside the oil tank by regulating and controlling the carbon tank ventilation valve and the carbon tank desorption valve, and the measured vacuum attenuation gradient of the oil tank is used for judging the leakage condition of the automobile oil tank after the automobile enters a low automobile speed or an engine enters a start-stop state under the condition of keeping the target vacuum degree for a period of time. The system is divided into two parts according to the influence degree of oil tank pressure fluctuation noise in the oil tank leakage diagnosis process and the specific requirement on the working condition of the engine, and the system is divided into two parts: the vacuum establishing stage which is insensitive to pressure noise but has specific requirements on the working condition of the engine is completed in the early stage, the oil tank can quickly enter the second part under the condition of keeping the target vacuum degree of the oil tank, and the second part is the detection of the vacuum attenuation gradient which is sensitive to the pressure noise but has no requirements on the working condition of the engine, so that the oil tank leakage diagnosis can be carried out on the vehicle type with the start-stop function under the condition of not inhibiting the start-stop working condition.
The method for diagnosing the leakage of the oil tank by adopting the pressure sensor establishes the target vacuum degree: closing the carbon tank desorption valve to restore the pressure of the oil tank to atmospheric pressure, then closing the carbon tank ventilation valve, opening the carbon tank desorption valve, and establishing the target vacuum degree of the oil tank by utilizing the vacuum of the air inlet manifold; and (3) carrying out closed-loop control on the target vacuum degree of the oil tank: when the vacuum degree of the oil tank is smaller than a set value, the carbon tank desorption valve is opened again until the vacuum degree is close to the target vacuum degree, the carbon tank desorption valve is closed, and the circulation is performed so as to maintain the target vacuum degree of the oil tank; keeping the target vacuum degree to wait for the vehicle speed to be lower than the vehicle speed threshold or the engine to enter a start-stop state; measuring the vacuum attenuation gradient of the oil tank and judging the leakage result: when the current vehicle speed is lower than a threshold value or the engine enters a start-stop state, the carbon tank desorption valve is closed, the oil tank pressure sensor measures the vacuum attenuation gradient of the oil tank, and whether the oil tank leaks or not is judged through the vacuum attenuation gradient of the oil tank. And after the vacuum attenuation gradient of the vacuum oil tank is measured, opening a carbon tank ventilation valve, closing the carbon tank ventilation valve when the pressure of the oil tank is recovered to the standard atmospheric pressure, measuring the fuel evaporation speed, subtracting the fuel evaporation speed from the vacuum attenuation gradient to obtain a corrected attenuation gradient, and judging that the oil tank leaks when the corrected attenuation gradient is larger than a set gradient value. In order to evaluate the influence of fuel evaporation on the leakage diagnosis result, the evaporation rate measuring module 6 is used for measuring the evaporation rate of the fuel, and the influence of other factors on the fuel evaporation rate in the vacuum attenuation gradient measuring process is reduced at the end of the vacuum attenuation gradient measurement, so that the measured fuel evaporation rate is basically the same as the vacuum attenuation gradient measuring process, and the reliability of the leakage diagnosis result is improved. The vacuum attenuation gradient is corrected through the fuel evaporation speed, so that the judged data are more accurate, the measurement of the evaporation speed is close to the measurement of the attenuation gradient, the influence of other factors on the fuel evaporation speed can be effectively reduced, and the judgment result of the fuel tank leakage is more reliable.
And (3) carrying out part diagnosis in the process of establishing the target vacuum degree, and closing the carbon tank desorption valve to ensure that the normally closed fault of the carbon tank ventilation valve is judged if the oil tank pressure measured by the oil tank pressure sensor cannot be recovered to the atmospheric pressure when the oil tank pressure is recovered to the atmospheric pressure. And closing the carbon tank vent valve to enable the pressure drop of the oil tank to exceed a pressure threshold value, judging that the carbon tank desorption valve is normally open, opening the carbon tank desorption valve when the pressure drop of the oil tank does not exceed the pressure threshold value, judging that the carbon tank desorption valve is normally closed if the vacuum of the oil tank cannot be established, and judging that the oil tank is a large leakage fault if the vacuum of the oil tank can be established but cannot reach a target vacuum degree. The diagnosis process of the parts and the oil tank vacuum establishing process are not sensitive to pressure noise but have specific requirements on the working condition of the engine, so that the diagnosis process of the parts is put in the establishing process of the target vacuum degree of the oil tank, the diagnosis time is shortened, the establishing of the target vacuum degree of the oil tank is ensured, and the final judgment of the attenuation gradient of the oil tank cannot be carried out when other parts have faults. And the oil tank leakage diagnosis is put forward early. And making a fault diagnosis of the parts. The oil tank leakage detection can be better realized.
And in the process of establishing the target vacuum degree, if any part is diagnosed to have fault or large leakage, the oil tank leakage diagnosis is quitted. And when the part is diagnosed to have a fault, the oil tank leakage diagnosis can be timely quitted, and the oil tank leakage diagnosis can be timely made. And keeping the target vacuum degree to wait for the vehicle speed to be lower than the vehicle speed threshold or the time for the engine to enter the start-stop state to exceed the set time threshold, and then exiting the oil tank leakage diagnosis. And when the target vacuum waiting time is too long, the fuel tank leakage diagnosis can be timely quitted, the start-stop working condition of the engine cannot be inhibited, and the method is suitable for start-stop function vehicle types.
According to the method, the pressure of the oil tank is recovered to the atmospheric pressure by closing the carbon tank desorption valve, then the carbon tank ventilation valve is closed, the carbon tank desorption valve is opened, the target vacuum degree of the oil tank is established by utilizing the vacuum of the air inlet manifold, after the target vacuum degree is established, closed-loop control is carried out by utilizing pressure data detected by the oil tank pressure sensor and the opening state of the carbon tank desorption valve, and the target vacuum degree of the oil tank is maintained. And in the process of maintaining the target vacuum degree of the oil tank, when the current speed of the vehicle is judged to be lower than the threshold value or the engine enters a start-stop state, the carbon tank desorption valve is closed, and the vacuum attenuation gradient of the oil tank is measured through the oil tank pressure sensor. And comparing the detected vacuum attenuation gradient of the oil tank with a set gradient value, and judging that the oil tank leaks when the vacuum attenuation gradient of the oil tank is greater than the set gradient value. And if the vacuum attenuation gradient of the oil tank is less than or equal to the set gradient value, judging that the oil tank does not leak. The invention utilizes the vacuum of the air inlet manifold to establish the vacuum degree in the oil tank by regulating and controlling the carbon tank ventilation valve and the carbon tank desorption valve, and the measured oil tank vacuum attenuation gradient is used for judging the leakage condition of the automobile oil tank after the automobile enters a low automobile speed or an engine enters a start-stop state under the condition of keeping the target vacuum degree for a period of time. And after the vacuum attenuation gradient of the oil tank is measured, establishing normal atmospheric pressure to measure the fuel evaporation speed of the oil tank, and subtracting the fuel evaporation speed from the vacuum attenuation gradient of the oil tank to obtain a corrected attenuation gradient. And comparing the corrected attenuation gradient with the set gradient value to judge the leakage condition of the oil tank, judging that the oil tank leaks when the corrected attenuation gradient is greater than the set gradient value, and judging that the oil tank does not leak when the corrected attenuation gradient is less than or equal to the set gradient value.
The method is divided into two parts according to the influence degree of oil tank pressure fluctuation noise in the oil tank leakage diagnosis process and the specific requirement on the engine working condition, and the method comprises the following steps: the vacuum establishing stage which is insensitive to pressure noise but has specific requirements on the working condition of the engine is completed in the early stage, the oil tank can quickly enter the second part under the condition of keeping the target vacuum degree of the oil tank, and the second part is the detection of the vacuum attenuation gradient which is sensitive to the pressure noise but has no requirements on the working condition of the engine, so that the oil tank leakage diagnosis can be carried out on the vehicle type with the start-stop function under the condition of not inhibiting the start-stop working condition.
The invention solves the defect that the method for diagnosing the leakage of the oil tank by using the pressure sensor is applied to starting and stopping vehicles, so that the method for the pressure sensor of the oil tank can meet the requirements of regulations by sacrificing less acceptable conditions when applied to starting and stopping vehicles, and the vehicle cost is reduced. The system and the method are also applicable to other conventional non-start-stop vehicles, but the advantages can be better embodied on the start-stop vehicle.
The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.
Claims (7)
1. A system for diagnosing fuel tank leakage using a pressure sensor, comprising
The vacuum degree establishing module (1) is used for closing the carbon tank desorption valve to enable the pressure of the oil tank to be recovered to the atmospheric pressure, then closing the carbon tank ventilation valve to open the carbon tank desorption valve, and establishing the target vacuum degree of the oil tank by utilizing the vacuum of the air inlet manifold;
the part diagnosis module (8) is used for diagnosing parts in the process of establishing a target vacuum degree, judging a normally closed fault of a carbon tank vent valve if the pressure of an oil tank measured by an oil tank pressure sensor cannot be recovered to the atmospheric pressure when a carbon tank desorption valve is closed so that the pressure of the oil tank is recovered to the atmospheric pressure, judging a normally open fault of the carbon tank desorption valve if the pressure of the oil tank is reduced by closing the carbon tank vent valve so that the pressure reduction amount of the oil tank exceeds a pressure threshold value, opening the carbon tank desorption valve if the pressure reduction amount of the oil tank does not exceed the pressure threshold value, judging a normally closed fault of the carbon tank desorption valve if the vacuum of the oil tank cannot be established, and judging a large leakage fault if the;
the vacuum degree maintaining module (2) is used for restarting the carbon tank desorption valve when the vacuum degree of the oil tank is smaller than a set value, and closing the carbon tank desorption valve until the target vacuum degree is close, so that circulation is performed, and the vacuum degree maintaining module is used for maintaining the target vacuum degree of the oil tank;
the waiting module (3) is used for keeping the target vacuum degree to wait that the vehicle speed is lower than a vehicle speed threshold value or the engine enters a start-stop state;
the attenuation gradient measuring module (4) is used for closing a carbon tank desorption valve when the current vehicle speed is lower than a threshold value or the engine enters a start-stop state, and an oil tank pressure sensor is used for measuring the vacuum attenuation gradient of the oil tank;
and the judgment module (5) judges whether the oil tank leaks or not through the vacuum attenuation gradient of the oil tank.
2. The system for diagnosing the fuel tank leakage by using the pressure sensor as claimed in claim 1, further comprising an evaporation rate measuring module (6), wherein after the attenuation gradient measuring module (4) performs the fuel tank vacuum attenuation gradient measurement, the canister vent valve is opened, and the canister vent valve is closed when the fuel tank pressure is recovered to the standard atmospheric pressure, wherein the data measured by the fuel tank pressure sensor is the fuel evaporation rate.
3. The system for diagnosing fuel tank leakage using a pressure sensor according to claim 2, characterized in that it further comprises a correction module (7) for subtracting the fuel evaporation rate from the vacuum decay gradient to obtain a corrected decay gradient; and the judgment module (5) judges that the oil tank leaks when the attenuation gradient comparison after correction is larger than the set gradient value.
4. The system for diagnosing the fuel tank leakage by using the pressure sensor as claimed in claim 1, further comprising an exit diagnosis module (9) which exits the fuel tank leakage diagnosis when any one time of component diagnosis is faulty or large leakage during the establishment of the target vacuum degree, and exits the fuel tank leakage diagnosis when the target vacuum degree is maintained to wait for the vehicle speed to be lower than the vehicle speed threshold or the time for the engine to enter the start-stop state to exceed the set time threshold.
5. A method for diagnosing fuel tank leakage by using a pressure sensor,
establishing a target vacuum degree: closing a carbon tank desorption valve to recover the pressure of an oil tank to atmospheric pressure, then closing a carbon tank vent valve to open the carbon tank desorption valve to establish a target vacuum degree of the oil tank by utilizing the vacuum of an air inlet manifold, performing part diagnosis in the process of establishing the target vacuum degree, closing the carbon tank desorption valve to recover the pressure of the oil tank to atmospheric pressure, judging that the carbon tank vent valve is normally closed if the pressure of the oil tank measured by an oil tank pressure sensor cannot recover to atmospheric pressure, closing the carbon tank vent valve to ensure that the pressure reduction of the oil tank exceeds a pressure threshold, judging that the carbon tank desorption valve is normally open, opening the carbon tank desorption valve when the pressure reduction of the oil tank does not exceed the pressure threshold, judging that the carbon tank desorption valve is normally closed if the vacuum of the oil tank cannot be established, and judging that the oil tank vacuum is a;
and (3) carrying out closed-loop control on the target vacuum degree of the oil tank: when the vacuum degree of the oil tank is smaller than a set value, the carbon tank desorption valve is opened again until the vacuum degree is close to the target vacuum degree, the carbon tank desorption valve is closed, and the circulation is performed so as to maintain the target vacuum degree of the oil tank; keeping the target vacuum degree to wait for the vehicle speed to be lower than the vehicle speed threshold or the engine to enter a start-stop state;
measuring the vacuum attenuation gradient of the oil tank and judging the leakage result: when the current vehicle speed is lower than a threshold value or the engine enters a start-stop state, the carbon tank desorption valve is closed, the oil tank pressure sensor measures the vacuum attenuation gradient of the oil tank, and whether the oil tank leaks or not is judged through the vacuum attenuation gradient of the oil tank.
6. The method of claim 5, wherein the tank leak is determined when the vacuum decay gradient of the vacuum tank is measured, the canister vent valve is opened, the canister vent valve is closed when the tank pressure returns to normal atmospheric pressure, the fuel evaporation rate is measured, the vacuum decay gradient minus the fuel evaporation rate is corrected to obtain a decay gradient, and the tank leak is determined when the decay gradient is greater than a predetermined value.
7. The method for diagnosing the leakage of the fuel tank by using the pressure sensor as claimed in claim 5, wherein in the process of establishing the target vacuum degree, the diagnosis of the leakage of the fuel tank is quitted if any one part is diagnosed to be faulty or large in leakage; and keeping the target vacuum degree to wait for the vehicle speed to be lower than the vehicle speed threshold or the time for the engine to enter the start-stop state to exceed the set time threshold, and then exiting the oil tank leakage diagnosis.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811026654.6A CN109281759B (en) | 2018-09-04 | 2018-09-04 | System and method for diagnosing leakage of oil tank by adopting pressure sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811026654.6A CN109281759B (en) | 2018-09-04 | 2018-09-04 | System and method for diagnosing leakage of oil tank by adopting pressure sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109281759A CN109281759A (en) | 2019-01-29 |
| CN109281759B true CN109281759B (en) | 2020-03-27 |
Family
ID=65183974
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811026654.6A Active CN109281759B (en) | 2018-09-04 | 2018-09-04 | System and method for diagnosing leakage of oil tank by adopting pressure sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109281759B (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110843785B (en) * | 2019-10-28 | 2021-01-15 | 浙江吉利汽车研究院有限公司 | Device and method for avoiding misdiagnosis of oil tank leakage |
| CN111075610B (en) * | 2019-12-11 | 2021-09-21 | 义乌吉利动力总成有限公司 | Carbon tank desorption pipeline flow diagnosis method and system |
| CN111103148B (en) * | 2019-12-18 | 2021-11-30 | 中国第一汽车股份有限公司 | Jam detection method and vehicle |
| CN111502870B (en) * | 2020-04-26 | 2021-12-07 | 上海元城汽车技术有限公司 | Diagnostic system and method |
| CN111608823B (en) * | 2020-05-13 | 2022-06-28 | 联合汽车电子有限公司 | Method for detecting opening delay of carbon canister valve and leakage of oil tank and leakage detection device |
| CN111845327B (en) * | 2020-07-20 | 2022-02-22 | 上海元城汽车技术有限公司 | Oil tank pressure monitoring method and device, vehicle and storage medium |
| CN112031946B (en) * | 2020-09-08 | 2023-04-07 | 广州汽车集团股份有限公司 | Fault diagnosis method for fuel evaporation system |
| CN113790895A (en) * | 2021-09-09 | 2021-12-14 | 安徽江淮汽车集团股份有限公司 | Fuel evaporation diagnosis test method and system based on hardware-in-the-loop |
| CN114687879A (en) * | 2022-03-31 | 2022-07-01 | 重庆长安汽车股份有限公司 | Vehicle fuel evaporation leakage diagnosis method |
| CN114607519A (en) * | 2022-03-31 | 2022-06-10 | 重庆长安汽车股份有限公司 | Fuel evaporation system leakage diagnosis method and fuel evaporation system |
| CN114934853B (en) * | 2022-06-16 | 2023-09-15 | 江铃汽车股份有限公司 | Fuel oil leakage diagnosis method |
| CN115263550B (en) * | 2022-07-29 | 2023-11-14 | 东风汽车集团股份有限公司 | Method, system and computer equipment for identifying noise of vehicle and fuel desorption system |
| CN115370475B (en) * | 2022-08-19 | 2023-10-13 | 东风汽车集团股份有限公司 | Diagnosis method and diagnosis system for oil tank leakage |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000073883A (en) * | 1998-09-02 | 2000-03-07 | Nissan Motor Co Ltd | Vapor fuel treatment device for internal combustion engine |
| CN1971022A (en) * | 2005-11-22 | 2007-05-30 | 日产自动车株式会社 | Leakage diagnosis device for evaporated fuel treatment device |
| CN103109067A (en) * | 2010-09-06 | 2013-05-15 | 大陆汽车有限责任公司 | Method for diagnosing fuel tank leaks, and apparatus applying same |
| CN103821626A (en) * | 2012-11-15 | 2014-05-28 | 福特环球技术公司 | Fuel system diagnostics |
| CN204299730U (en) * | 2014-11-25 | 2015-04-29 | 奇瑞汽车股份有限公司 | A kind of vehicle fuel oil evaporation discharging system |
| CN108223200A (en) * | 2017-12-14 | 2018-06-29 | 湖南吉利汽车部件有限公司 | A kind of system and diagnostic method for supporting fuel vaporization leakage diagnosis |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6658923B2 (en) * | 2000-02-22 | 2003-12-09 | Siemens Automotive S.A. | Leak detection a vapor handling system |
-
2018
- 2018-09-04 CN CN201811026654.6A patent/CN109281759B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000073883A (en) * | 1998-09-02 | 2000-03-07 | Nissan Motor Co Ltd | Vapor fuel treatment device for internal combustion engine |
| CN1971022A (en) * | 2005-11-22 | 2007-05-30 | 日产自动车株式会社 | Leakage diagnosis device for evaporated fuel treatment device |
| CN103109067A (en) * | 2010-09-06 | 2013-05-15 | 大陆汽车有限责任公司 | Method for diagnosing fuel tank leaks, and apparatus applying same |
| CN103821626A (en) * | 2012-11-15 | 2014-05-28 | 福特环球技术公司 | Fuel system diagnostics |
| CN204299730U (en) * | 2014-11-25 | 2015-04-29 | 奇瑞汽车股份有限公司 | A kind of vehicle fuel oil evaporation discharging system |
| CN108223200A (en) * | 2017-12-14 | 2018-06-29 | 湖南吉利汽车部件有限公司 | A kind of system and diagnostic method for supporting fuel vaporization leakage diagnosis |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109281759A (en) | 2019-01-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109281759B (en) | System and method for diagnosing leakage of oil tank by adopting pressure sensor | |
| CN111472899B (en) | Leakage diagnosis method and device for fuel oil evaporative emission system | |
| JP4616739B2 (en) | Method for detecting evaporative fuel emissions in a vehicular fuel vapor control system | |
| US8418525B2 (en) | Method for testing the operability of a tank shutoff valve of a fuel tank system | |
| US7963150B2 (en) | Method to test for a leak in a fuel tank system | |
| US6220229B1 (en) | Apparatus for detecting evaporative emission control system leak | |
| JP4026348B2 (en) | Evaporative gas purge system leak diagnosis device | |
| JP4764025B2 (en) | Method for inspecting functionality of tank ventilation device for automobile having internal combustion engine | |
| JPH0861164A (en) | Inspecting method of normalcy of function of tank ventilating device | |
| US20070068227A1 (en) | Leak diagnostic apparatus for a vaporized fuel processing system | |
| US6321728B1 (en) | Apparatus and method for diagnosing faults of fuel vapor treatment unit | |
| US8365706B2 (en) | Method and device for testing the tightness of a fuel tank of an internal combustion engine | |
| US8958941B2 (en) | Diagnostic method and device for a purge valve of a hybrid motor vehicle | |
| US6487892B1 (en) | Fault detection apparatus and method for fuel vapor purge system | |
| CN117212002A (en) | Leakage detection method of fuel evaporation system and electronic equipment | |
| US8943878B2 (en) | Method and device for detecting the blockage of a gasoline vapor filter purge valve | |
| CN111691995B (en) | Fuel steam control method and device | |
| US7136741B2 (en) | Apparatus and method for controlling vehicle | |
| JPH09137756A (en) | Failure diagnostic device for evaporated fuel transpiration preventive device of internal combustion engine and fuel supplying midst detection device | |
| KR101252776B1 (en) | Apparatus and method for evaporative leakage diagnosis | |
| CN114607519A (en) | Fuel evaporation system leakage diagnosis method and fuel evaporation system | |
| KR101885945B1 (en) | Method for diagnosing a tank ventilation valve | |
| KR101558977B1 (en) | Apparatus for dignosing stuck of pressure switch for natural vaccum leak detection and method thereof | |
| CN107476892B (en) | Engine control method and system and vehicle | |
| KR20220062384A (en) | Method and device for diagnosing a ventilation line of a fuel tank of a motor vehicle capable of being driven by an internal combustion engine |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |