KR100482555B1 - System for checking fuel leakage from fuel line and method for the same - Google Patents

Abstract

Disclosed are a fuel leakage diagnosis system and a method of a vehicle fuel line. The fuel leakage diagnosis method of the fuel line of the disclosed vehicle is characterized in that the canister collects the gas evaporated from the fuel tank of the vehicle and detects the fuel leakage of the fuel line connected therebetween to supply the surge tank through the duty control of the purge control solenoid valve. A fuel leakage diagnosis method of a fuel line of a vehicle to be diagnosed, the method comprising: (a) checking an operation state of the purge control solenoid valve and determining whether the purge control solenoid valve is operated; (b) determining whether the amount of fuel supplied to the purge control solenoid valve and the amount of fuel used for the solenoid of the surge tank is zero or more; (c) determining whether or not a value obtained by subtracting the amount of fuel used for the surge tank from the supply fuel of the purge control solenoid valve is equal to or greater than a threshold value when the condition of step (b) is satisfied; (d) determining that fuel is leaking from the fuel line from the purge control solenoid valve to the surge tank by the electronic control apparatus of the vehicle when the condition in step (c) is satisfied; It is characterized by that.

According to the present invention, it is possible to cope with the strengthening regulations, even the fuel line from the purge control solenoid valve to the surge tank can be diagnosed whether the fuel leaks, there is an advantage that the driver can be quickly maintained.

Description

Fuel leakage diagnosis system of vehicle fuel line and method thereof {SYSTEM FOR CHECKING FUEL LEAKAGE FROM FUEL LINE AND METHOD FOR THE SAME}

The present invention relates to a fuel leakage diagnosis system and method for a fuel line of a vehicle, and more particularly, a fuel line of a vehicle to diagnose fuel leakage in a fuel supply line in real time so that the maintenance of the fuel line can be promptly received. A fuel leakage diagnosis system and method thereof are provided.

Currently, the Evaporative Check detects up to 0.5mm, for example, due to the tightening of emission regulations, and turns on the malfunction indicator (MIL) if it detects a leak in the fuel line. And OBD-II regulations preclude tubing and connections between purge valves and intake manifolds that cause HC (hydrocarbon) loss to the atmosphere and purge flows from efferential systems. (purge flow) and efferentiated systems should be monitored.

That is, when the electronic control unit (hereinafter referred to as ECU) of the vehicle becomes an ephemeral check diagnosis condition, the canister, purge control solenoid valve (hereinafter referred to as PCSV) from the fuel tank. Should be checked for leakage of fuel lines.

Figure 1 is a block diagram schematically showing the configuration of a fuel line system of a typical vehicle.

  As shown, the canister 12 collects the gas evaporated from the fuel tank 11 and the surge tank 14 or the intake manifold, or the throttle body through the duty control of the PCSV 13. It is supplied to the (Throttle Body) (hereinafter referred to as a surge tank) to prevent the engine from relieving the engine during idle or part load. As a result, in order to prevent the release (leakage) of the gas, which is fuel, to the atmosphere in the fuel line 15 connecting them, it is regulated to perform an efferential check according to the OBD-II law.

Meanwhile, the principle of efferential check of the fuel line 15 is as follows. First, when the diagnostic condition is reached, the shutoff valve 12a of the canister 12 and the valve of the PCSV 13 are closed to measure the fuel pressure of the fuel tank 11, and after the fuel pressure is measured, the diagnosis of fuel leakage is performed. In order to check whether the pressure drops in time by opening the PCSV 13 and giving a negative pressure, the PCSV 13 is closed again to check whether the fuel pressure is increased again in time. As such, a second large amount of leak is examined and a third small amount of leak is diagnosed.

In addition, a purge nipple 16 is installed in the surge tank 14 to diagnose the leakage of the fuel in the fuel line 15 in FIG. 1.

On the other hand, the current OBD-II legislation shows that, as mentioned above, efferential system monitoring excludes tubing and connections between the purge valve and the intake manifold causing HC losses to the atmosphere. It is said that the purge flow and the effervescent system from the system should be monitored.

However, current legislation is intended to diagnose the fuel leakage of the fuel line 15 from the fuel tank 11 to the PCSV 13, but in order to cope with the increasingly severe exhaust gas regulations, Must detect the fuel line 15 from the PCSV 13 to the surge tank 14.

The present invention was created to solve the above problems, taking into account the ever-increasing regulations of exhaust gas, fuel supply line from the PCSV to the surge tank, intake manifold, or throttle body in order to strengthen the evaporative check. Diagnosis of fuel leakage in real time to reduce the emission of exhaust gas by allowing the fuel line to be repaired quickly, and to minimize fuel leakage to improve fuel economy and output of the vehicle's fuel line. The purpose is to provide a method.

Fuel leakage diagnosis system of the fuel line of the vehicle of the present invention for achieving the above object, the canister collects the gas evaporated from the fuel tank of the vehicle, so as to supply to the surge tank through the duty control of the purge control solenoid valve. A fuel leakage diagnosis system of a fuel line of a vehicle for diagnosing fuel leakage of a fuel line connected therebetween, wherein the fuel line detection unit is installed in the fuel line on one side of an inlet of the surge tank and has a fuel amount detecting unit configured to detect the amount of fuel passing therethrough. Solenoids; An electronic controller connected to the solenoid to determine the leakage of fuel from the fuel line in response to a signal of the fuel amount detector; It is characterized in that it comprises a; malfunction indicator light provided to inform the leakage of fuel in response to the fuel leakage determination signal of the electronic control device.

In the fuel leakage diagnosis method of the vehicle fuel line of the present invention for achieving the above object, the canister collects the gas evaporated from the fuel tank of the vehicle, so as to supply to the surge tank through the duty control of the purge control solenoid valve. In the fuel leakage diagnosis method of the fuel line of the vehicle for diagnosing the fuel leakage of the fuel line connected between them, (a) checking the operation state of the purge control solenoid valve, and determining the operation of the purge control solenoid valve Wow; (b) determining whether the amount of fuel supplied to the purge control solenoid valve and the amount of fuel used for the solenoid of the surge tank is zero or more; (c) determining whether or not a value obtained by subtracting the amount of fuel used for the surge tank from the supply fuel of the purge control solenoid valve is equal to or greater than a threshold value when the condition of step (b) is satisfied; (d) determining that fuel is leaking from the fuel line from the purge control solenoid valve to the surge tank by the electronic control apparatus of the vehicle when the condition in step (c) is satisfied; It is characterized by that.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram schematically illustrating a system for diagnosing a fuel leakage of a fuel line of a vehicle according to the present invention. Here, the description of the configuration of the fuel leakage diagnosis system of the fuel line of the general vehicle will be omitted, and only the configuration according to the features of the present invention will be described.

Referring to the drawings, the fuel leakage diagnosis system of the vehicle fuel line according to the present invention, the canister 22 collects the gas evaporated from the fuel tank 21 of the vehicle, the surge through the duty control of the PCSV (23) By diagnosing the fuel leakage of the fuel line 25 connected between them to supply to the tank 24, it is installed in the fuel line 25 on one side of the inlet of the surge tank 24, and detects the amount of fuel passing therethrough A solenoid 26 having a fuel amount detection unit 29 and an ECU 27 connected to the solenoid 26 to determine the leakage of fuel in the fuel line 25 in response to a signal of the fuel amount detection unit 29; In addition, when there is a fuel leak in the fuel line 25, the fuel leakage determination signal of the ECU 27 includes a malfunction indicator (MIL) 28 provided to inform the leakage of the fuel.

By applying the fuel leakage diagnosis system of the fuel line of the vehicle according to the present invention having the configuration as described above, the fuel leakage diagnosis of the fuel line of the vehicle according to the present invention will be described as follows.

Here, the description of the fuel leakage diagnosis method of the fuel line of the general vehicle will be omitted, and only the features of the method according to the present invention will be described.

FIG. 3 is a schematic flowchart sequentially illustrating a fuel leakage diagnosis method of a fuel line of a vehicle according to the present invention.

Referring to the drawings, first of all, by checking the operating state of the PCSV 23, it is determined whether or not the PCSV 23 is operating (steps 110 and 120).

Subsequently, it is determined whether the amount of fuel supplied to the PCSV 23 is equal to or greater than zero, and the amount of fuel used for the solenoid 26 provided at the inlet side of the surge tank 24 is equal to or greater than zero (steps 130 and 140).

When the conditions of steps 130 and 140 are satisfied, it is determined whether the amount of fuel supplied from the solenoid 26 of the surge tank 24 is subtracted from the amount of fuel supplied to the PCSV 23 (step 150).

When the condition of step 150 is satisfied, the ECU 27 of the vehicle determines that fuel is leaking into the fuel line 25 from the PCSV 23 to the surge tank 24. (Step 160).

On the other hand, if it is determined that the fuel is leaking in the step 160, the malfunction indicator 28 is turned on to inform the leakage of the fuel (step 170).

After the fuel is supplied from the PCSV 23 to the solenoid 26 as described above, the fuel supply amount of the PCSV 23 is greater than 0 to determine the leakage of the fuel, and then the amount of fuel used in the solenoid 26 is zero. If the fuel level detection unit 29 detects a larger value, the fuel line 25 is naturally filled with fuel, and then the fuel amount is compared in the fuel line 25 by comparing their fuel amounts.

The present invention made as described above, the fuel from the PCSV (23) to the surge tank 24, which has not been able to perform the conventional check function in the future for strengthening the separate check in consideration of the increasingly severe exhaust gas regulation. Diagnoses the fuel leakage of the fuel line 25 supplied with fuel in real time, and if the fuel is leaking, a malfunction indicator 28 is turned on so that the driver can be promptly maintained on the fuel line 25 to reduce the emission of exhaust gas. The aim is to help improve fuel economy and output by suppressing fuel leakage as much as possible.

As such, in order to diagnose in real time whether the fuel line 25 from the PCSV 23 to the surge tank 24 is leaked in real time, a system in which a purge nipple is installed in the surge tank 24 and connected with a fuel hose (FIG. 1). By installing a solenoid 26 for supplying fuel evaporation gas to the engine at the end of the fuel line 25, the ECU 27 supplies the fuel to the surge tank 24 by controlling the duty with respect to time. Let's do it.

In this case, since the ECU 27 performs the duty control, the fuel injection amount with respect to time can be accurately known, and since the solenoid 26 of the PSCV also performs the duty control, the fuel supply amount can be accurately diagnosed with respect to the time. As a result, the fuel supply amount of the PSCV and the fuel injection amount of the solenoid 26 of the surge tank 24 with respect to these times can be calculated to compare the supply amount and the amount of use in real time to diagnose whether the fuel leak has not been detected before.

4 is a graph showing the fuel (gas) injection quantity Q exiting through the solenoid 26 with respect to time t. In this graph, the areas A and A 'are the amount of fuel injected for a predetermined time, that is, the areas A and A' are 1 cycle in the injection amount graph of the gas exiting through the duty control of the solenoid 26 with respect to time. ) Represents the amount of fuel going out through the solenoid (26).

There is no particular diagnostic condition, but from the time when the fuel is filled in the fuel line 25 from the PCSV 23 to the surge tank 24, the PCSV 23 determines the instantaneous supply fuel amount and the instantaneous use fuel amount of the surge tank 24. Diagnose in real time.

As a result, only the fuel amount of the PCSV 23 and the fuel amount of the solenoid 26 of the surge tank 24 are detected. In other words, the fuel line 25 is filled with fuel when the supply fuel amount of the PCSV 23> 0 and the use fuel amount of the surge tank 24 are> 0.

The diagnosis is excluded when there is no fuel input of the PCSV 23, that is, when there is no fuel exiting from the PCSV 23, and when the PCSV 23 is not operated. That is, it is applied only when the PCSV 23 is operated according to the engine conditions. In addition, FIG. 4 is a graph illustrating the flow rate characteristics of the PCSV 23 and the solenoid, and shows the amount of gas injected through the solenoid over time. Referring to FIG. 4, both the solenoids 26 installed in the PCSV 23 or surge tank 24 are controlled by duty and valve open time. The injection amount graph area A of the gas exiting through the duty control is the amount of fuel exiting through the solenoid 26 during one cycle. The solenoid 26 passes through the fuel amount detection unit 29 and enters the ECU 27, which is the amount of gas injection through the solenoid 26 with respect to time. This is simultaneously applied to the PCSV 23 and the solenoid 26. However, the fuel amount supplied through the PCSV 23 is supplied to the engine by the ECU 27 considering the duty amount of the PCSV 23 and the valve open time. In this case, the duty amount must be considered when calculating the amount of fuel supplied through the solenoid 26. Therefore, only a part of the valve is opened compared to the maximum valve opening according to the engine load (ratio = Duty amount) This is because the fuel supply amount is proportional to time in consideration of the duty amount.

As described above, the fuel leakage diagnosis system and method of the fuel line of the vehicle according to the present invention have the following effects.

In consideration of the exhaust gas regulations to be tightened in the future, the fuel line from PCSV to surge tank is diagnosed in real time.In case of an abnormality, the ECU determines that the fuel is leaking and turns on the malfunction indicator light. Prevents, improves fuel economy and fuel supply, improves output.

In addition, it is possible to cope with the tightening regulations, and even the fuel line from the PCSV to the surge tank, which could not be diagnosed in the past, can diagnose fuel leakage.

The system configuration or control logic is simple because the ECU diagnoses fuel leakage by comparing fuel consumption only without any special restriction condition and informs the driver by lighting a malfunction indicator. The operator can also be serviced quickly.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent embodiments are possible. Therefore, the true scope of protection of the present invention should be defined only by the appended claims.

1 is a block diagram schematically showing the configuration of a fuel line system of a typical vehicle.

Figure 2 is a block diagram schematically showing the configuration of a fuel leakage diagnosis system of a fuel line of a vehicle according to the present invention.

Figure 3 is a schematic flowchart showing sequentially a fuel leakage diagnosis method of a fuel line of a vehicle according to the present invention.

Figure 4 is a schematic graph showing the relationship between time and the amount of gas injection through the solenoid.

<Description of the symbols for the main parts of the drawings>

21. Fuel Tank

22. Canister

23.PCSV

24. Surge Tank

25. Fuel Line

26. Solenoid

27. ECU

28. Malfunction indicator

Claims (3)

The canister collects the gas evaporated from the vehicle's fuel tank and supplies fuel to the surge tank through the duty control of the purge control solenoid valve to diagnose the fuel leakage of the fuel line of the vehicle. In A solenoid installed at the fuel line on one side of the inlet of the surge tank, the solenoid having a fuel amount detecting unit detecting a fuel amount passing therethrough; An electronic controller connected to the solenoid to determine the leakage of fuel from the fuel line in response to a signal of the fuel amount detector; And a malfunction indicator provided to receive a fuel leakage determination signal of the electronic controller to inform the leakage of the fuel. The canister collects the gas evaporated from the fuel tank of the vehicle, and the fuel leakage diagnosis method of the fuel line of the vehicle which diagnoses the fuel leakage of the fuel line connected between them to supply the surge tank through the duty control of the purge control solenoid valve. In (a) checking the operation state of the purge control solenoid valve and determining whether the purge control solenoid valve is operated; (b) determining whether the amount of fuel supplied to the purge control solenoid valve and the amount of fuel used for the solenoid of the surge tank is zero or more; (c) determining whether or not a value obtained by subtracting the amount of fuel used for the surge tank from the supply fuel of the purge control solenoid valve is equal to or greater than a threshold value when the condition of step (b) is satisfied; (d) determining that fuel is leaking from the fuel line from the purge control solenoid valve to the surge tank by the electronic control apparatus of the vehicle when the condition in step (c) is satisfied; A fuel leakage diagnostic method of a vehicle fuel line, characterized in that. The method of claim 1, If it is determined in step (d) that the fuel of the fuel line is leaking, the method further comprises the step of turning on a malfunction indicator to inform the leakage of fuel.