KR100860228B1 - Method for detecting open of positive crankcase ventilation hose cap of intake system - Google Patents

Abstract

A method for diagnosing the opening of the PCV hose cap of an intake system is disclosed that can improve stability at engine idle. The present invention, a) calculates a target engine speed from the intake air amount in the intake manifold through an engine controller and determines whether the difference between the calculated target speed and the received engine speed is less than a predetermined value and the determination result engine Predicting the opening of the cap of the PCV hose when the rotation speed difference is greater than or equal to the predetermined value; b) setting the position of the throttle valve to the closed state after setting the open diagnosis mode of the PCV hose cap when the ignition key is in the off state after detecting the position of the ignition key; c) Receive and store the intake air amount in the intake manifold as the first intake air amount, and determine whether a predetermined time has elapsed, and if the predetermined time elapses, receive the intake air amount in the intake manifold and store it as the second intake air amount. Doing; And d) calculating a difference between the first intake air amount and the second intake air amount and determining that the cap of the PCV hose is in an open state when the difference between the intake air amounts is greater than or equal to a preset threshold value. Terminating the step.

Automotive, Blow By Gas, Leakage, Crankcase, Reburn, Engine

Description

METHOD FOR DETECTING OPEN OF POSITIVE CRANKCASE VENTILATION HOSE CAP OF INTAKE SYSTEM}

1 is a view showing the configuration of an intake system to which the present invention is applied.

2 is a flowchart illustrating a PCV hose cap opening diagnosis process of the intake system according to the present invention.

FIG. 3 is a waveform diagram illustrating output signals of respective units in the intake system shown in FIG. 2.

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

11: idle control valve 13 throttle valve

15: throttle position sensor 17: intake manifold,

19: map sensor 21: engine

23: engine controller 25: PC V hose

The present invention relates to a method for diagnosing PCV hose cap opening of an intake system, and more particularly, to diagnose the PCV hose cap opening state from the difference of the amount of intake air supplied from the crankcase to the intake manifold to improve stability at engine idle. It's about how you can.

A general vehicle is a transport port that can travel freely on a road without a rail by using the power of an engine installed in a vehicle body, and has high maneuverability, adjustability, stability, and security.

Fuel used as a driving force for moving such automobiles is usually gasoline, which is mixed with air (or fuel only) by a fuel device and supplied to each cylinder.

With the recent development of the industry, the number of automobiles is rapidly growing, and the exhaust gas emitted from the automobiles is the main culprit of environmental pollution. In order to reduce such environmental pollution, each country is making efforts to reduce the amount of emissions from automobiles, and the automobile emission regulations (OBD-ii), which is regulated in California, is being prepared.

That is, to detect the leakage of the intake system, which is one of the items requiring failure diagnosis of all systems affecting the emission of the vehicle, and to regulate the engine controller to accurately detect the leakage required by current regulations. Deciding.

However, currently developed or mass-produced vehicles are not provided with a method of accurately diagnosing the leakage of blow-by gas by opening the cap of the positive crankcase ventilation (PCV) hose. .

Therefore, in the event of a leak, harmful gases are released into the atmosphere, which causes serious environmental problems and serious adverse effects on driving of the vehicle. That is, when leakage occurs in the intake system, there is a problem of starting off and idling due to misfire and poor air-fuel ratio control.

 The present invention is to solve such a problem, an object of the present invention is to accurately diagnose the opening of the PVC hose cap for introducing the blow-by gas in the crankcase to the intake manifold, which can safely perform idle control of the engine An object of the present invention is to provide a method for diagnosing PCV hose cap opening of an intake system.

CV hose cap opening diagnostic method of the intake system of the vehicle according to the present invention for achieving the above object,

A method of controlling an intake system in which blow-by gas in a crankcase is introduced into an intake manifold through a PCV hose, and

a) calculating a target engine speed from the amount of intake air in the intake manifold through an engine controller; and determining whether the difference between the calculated target speed and the received engine speed is less than or equal to a predetermined value. Predicting that the PCV cap is opened when a predetermined value or more is exceeded;

b) setting the position of the throttle valve to the closed state after setting the open diagnosis mode of the PCV hose cap when the ignition key is in the off state after detecting the position of the ignition key;

c) Receive and store the intake air amount in the intake manifold as the first intake air amount, and determine whether a predetermined time has elapsed, and if the predetermined time elapses, receive the intake air amount in the intake manifold and store it as the second intake air amount. Doing;

d) canceling the PCV hose cap open diagnosis mode after calculating the difference between the first intake air amount and the second intake air amount and determining that the difference between the intake air amounts is greater than or equal to a preset threshold value, the PCV hose cap being opened. Including the steps of:

e) determining and displaying the PCV hose cap as normal when the difference between the first intake air amount and the second intake air amount is less than the threshold in step d).

The method may further include f) controlling opening of the throttle valve to a preset threshold value after the step d).

According to the present invention, the opening of the PCV hose cap is predicted from the difference between the target engine speed and the actual rotation speed calculated according to the intake air amount, and the ignition key is turned off and the throttle valve is completely closed and the received amount of intake air is received at a predetermined time difference. By determining the open state of the PCV hose cap from the vehicle, by accurately diagnosing the PCV hose cap opening, it is possible to safely perform unstable idle control due to the PCV hose cap opening.

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

1 is a view showing the configuration of a leak detection apparatus of the intake machine to which the leak diagnosis method of the intake system according to the present invention is applied. As shown therein, the leak detection apparatus of the intake machine to which the present invention is applied includes an idle control valve 11, a throttle valve 13, a throttle position sensor 15, an intake manifold 17, and a map sensor 19. ), An engine 21, an engine controller 23, and a PVC hose 25.

Here, the idle control valve 11 adjusts the bypass air amount to adjust the idle speed. The throttle position sensor 15 detects the rate of change of the opening degree of the throttle valve 13 which is linked to the driving of the accelerator pedal, and outputs information on it. The intake manifold 17 mixes the air supplied through the throttle valve 13 with the fuel supplied from the canister (not shown) and the blow-by gas supplied through the PCB hose 25 to the engine 21. It is provided to supply. At this time, the intake air amount is measured by the map sensor 19, the intake air amount information is supplied to the engine controller (23).

The engine controller 23 predicts the blow-by gas leakage due to the opening of the PCV hose cap from the difference between the target engine speed and the actual speed calculated according to the received intake air amount, the ignition key is turned off and the throttle valve is turned off. It is provided to confirm the opening of the PCV cap from the difference in the amount of intake air received at a predetermined time difference after the full closing control.

FIG. 2 is a flowchart illustrating a leak diagnosis process of an intake system generated in a state where the PCB hose cap is opened by the control of the engine controller illustrated in FIG. 1, and FIG. 3 is a waveform diagram illustrating output signals of respective units shown in FIG. 2. It is also. A leak diagnosis process of the intake system according to the present invention will be described with reference to FIGS. 1 to 3.

The engine controller 23 receives the intake air amount in the intake manifold (not shown) (step 101), and calculates the target engine speed in the idle state according to the received intake air amount (103).

Subsequently, the engine controller 23 receives the engine speed (105), calculates a difference between the received engine speed and the target engine speed calculated from the step (103), and calculates the difference between the calculated engine speeds (107). The preset value is compared with a preset value (109).

As a result of the comparison of step 109, when the engine speed difference is greater than or equal to the predetermined value, the engine controller (as shown in b) of FIG. 3 is estimated by the opening of the PCV hose cap as shown in a) of FIG. 23 sets the blow-by gas leak diagnosis mode due to the opening of the PCV hose cap as shown in FIG. 3 c) after stopping the engine (111).

Thereafter, the engine controller 23 receives the intake air amount in the intake manifold supplied from the map sensor 19 after the control of the throttle valve is completely closed, as shown in d) of FIG. 3. The amount of intake air is stored (117). At this time, the first intake air amount is as shown in e) of FIG.

In addition, the engine controller 23 determines whether a predetermined predetermined time has elapsed as shown in f) of FIG. 3, and if the predetermined time has elapsed, the engine controller 23 is supplied from the map sensor 19. An intake air amount in the intake manifold is received and stored as a second intake air amount (121). The second intake air amount is as shown in g) of FIG. 3.

Subsequently, the engine controller 23 calculates a difference between the first intake air amount and the second intake air amount received through the steps 117 and 121 (123), and the difference between the intake air amount and the preset threshold and In comparison, if the difference between the intake air amounts is greater than the threshold, it is determined after determining that the PCV hose cap is in an open state (125).

In other words, the difference in the intake air amount occurs above the threshold value despite the closed control state of the throttle valve means that the PCV hose cap is in the open state.

Thereafter, the engine controller 23 releases the opening diagnosis mode of the PCV hose cap 127 and then controls the opening of the throttle valve to a pre-stored threshold value to improve the engine startability thereafter (129).

On the other hand, if the difference between the intake air amount through the step 125 is larger than the threshold value, the state of the PCV hose cap is determined to be normal (131) and then proceeds to the step 127.

As described above, the PCV hose opening diagnosis method of the intake system according to the present invention predicts the opening of the PCV hose cap from the difference between the target engine speed and the actual rotation speed calculated according to the intake air amount, and the ignition key is turned off. Unstable idling control due to PCV hose cap opening by accurately diagnosing PCV hose cap opening by determining the opening state of PCV hose cap from the difference in intake air volume received after a predetermined time difference after the throttle valve is fully closed. Get the effect of running safely.

As such, those skilled in the art to which the present invention pertains will understand that the present invention may be embodied in other specific forms without changing to the technical spirit or essential features of the present invention. Therefore, the above-described embodiments are to be understood in all respects as illustrative and not restrictive. The scope of the present invention is shown by the following claims rather than the above description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. .

Claims (3)

A method of controlling an intake system in which blow-by gas in a crankcase is introduced into a intake manifold through a positive crankcase ventilation (PCV) hose, a) calculating a target engine speed from the amount of intake air in the intake manifold through an engine controller; and determining whether the difference between the calculated target speed and the received engine speed is less than or equal to a predetermined value. Predicting the opening of the cap of the PCV hose if it is above a predetermined value; b) setting the cap opening diagnosis mode of the PCV hose when the ignition key is in the off state after detecting the position of the ignition key and setting the position of the throttle valve to the closed state; c) Receive and store the intake air amount in the intake manifold as the first intake air amount, and determine whether a predetermined time has elapsed, and if the predetermined time elapses, receive the intake air amount in the intake manifold and store it as the second intake air amount. Doing; And d) calculating the difference between the first intake air amount and the second intake air amount, and if the difference between the intake air amounts is greater than or equal to a preset threshold value, determines that the cap opening state of the PCV hose is determined, and then sets the cap open diagnosis mode of the PCV hose. PCV hose cap opening diagnostic method of the intake system, characterized in that it comprises the step of canceling. The method of claim 1, further comprising e) controlling opening of the throttle valve to a predetermined threshold value after performing step d). The method of claim 1 or 2, further comprising: f) determining and displaying the cap of the PCV hose as normal when the difference between the first intake air amount and the second intake air amount is less than or equal to a preset threshold in step d). PCV hose cap opening diagnostic method of the intake system comprising a.

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