KR100282870B1 - Air volume control method during engine warm-up - Google Patents

Abstract

In the engine air-fuel ratio control method, when the vehicle accelerates during constant speed or deceleration, the air-fuel ratio is leanly controlled due to a decrease in fuel amount caused by the air-fuel ratio control, so that the vehicle output is lowered. In order to prevent this from falling, when the air-fuel ratio control signal of the vehicle falls below a predetermined value, the air-fuel ratio control is stopped so that the air-fuel ratio control signal does not fall below a predetermined signal value and the throttle valve is opened according to the driver's accelerator pedal operation. When the change in the quantity increases by more than a predetermined value, the air-fuel ratio control is executed from the predetermined minimum reference signal value to prevent the air-fuel ratio control signal value from falling below a predetermined reference value when the engine operating state falls within the warm-up period. Excessive fuel injection and / or lean due to air-fuel ratio control There is an effect capable of preventing vehicle drivability and emissions reduction in harmful exhaust gas by the fuel injection.

Description

Air volume control method during engine warm-up

The present invention relates to air volume control, and more particularly, to a method of controlling air volume during warming up of an engine for improving emission and operability of harmful exhaust gas by controlling the air volume during warming up of an engine.

In general, a vehicle that uses oil as a fuel supplies the engine with the appropriate fuel and air in accordance with the driving condition based on the air-fuel ratio that theoretically adjusts the fuel and air mixture ratio to prevent the emission of harmful exhaust gases. .

However, in the engine warm-up state in which the coolant temperature of the vehicle is below a predetermined reference value of 80 ° C., a large amount of oxygen contained in the exhaust gas discharged after being sucked into the vehicle engine with air and burned with air is very lean. It is becoming a problem of air pollution.

Accordingly, in order to solve the above problem, the air-fuel ratio control signal Ti-LAM is output to control the intake of fuel amount according to the air amount sucked from the electronic control device (hereinafter referred to as ECU) as shown in FIG. The amount of fuel was reduced to match the air-fuel ratio.

However, in the above-mentioned conventional technology, when the vehicle accelerates during constant speed or deceleration, the air-fuel ratio is leanly controlled due to a decrease in fuel amount due to the air-fuel ratio control, so that the vehicle output is lowered. There is a problem of this deterioration.

Accordingly, an object of the present invention is to solve the above problems, and when the air-fuel ratio control signal of the vehicle falls below a predetermined value, the air-fuel ratio control is stopped to prevent the air-fuel ratio control signal from falling below a predetermined signal value. It is an object of the present invention to provide a method for controlling the air amount during engine warm-up when the change in the throttle valve opening amount is increased by more than a predetermined value.

1 is a block diagram illustrating a configuration of an apparatus for controlling air volume during warming up of an engine according to an embodiment of the present invention;

2 is a flowchart illustrating a method for controlling air volume during engine warm-up according to an embodiment of the present invention;

3 is a graph of air volume control during engine warm-up according to an embodiment of the present invention;

4 is a graph of air volume control during conventional engine warm-up.

The present invention for achieving the above object,

In the engine air-fuel ratio control method of the vehicle, it is determined whether the operating state of the engine while driving is a warm-up section, and when the engine belongs to the warm-up section, it is determined whether an air-fuel ratio control signal (λ-Control) for vehicle exhaust gas control is output. Making a step;

When the air-fuel ratio control signal λ-Control for controlling the vehicle exhaust gas is output in the step, determining whether the control signal value Ti-LAM for the air-fuel ratio control is output below a predetermined reference value Min_Thb_LAM. Wow;

In this step, when the control signal value Ti-LAM for controlling the air-fuel ratio is output below the predetermined reference value Min_Thb_LAM, the control signal is temporarily suspended and the air-fuel ratio control signal value is set to maintain the predetermined minimum reference value. Outputting;

Determining whether the change value of the throttle valve opening amount is changed to a predetermined reference value or more when the driver's accelerator pedal operation for acceleration during deceleration is made by driving the vehicle in the step and controlling the air-fuel ratio;

When the throttle valve opening amount change value according to the driver's accelerator pedal operation is changed to a predetermined reference value or more, the control signal for controlling the air-fuel ratio is output from the predetermined reference value Min_Thb_LAM set for the air-fuel ratio control to the actuator. Characterized in that further comprises.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention, which can be achieved and realized in detail by the above objects, will be described in detail with reference to the accompanying drawings.

As shown in Figure 1, the configuration of the air amount control apparatus during engine warm-up according to an embodiment of the present invention,

Vehicle operation state detection means (10) for detecting a signal that is variable and output according to the vehicle operation state and outputting a predetermined electric signal;

When the air-fuel ratio control signal is output below the predetermined minimum value during the warm-up period by receiving the signal detected by the vehicle operation state detecting means 10, the output of the air-fuel ratio control signal is controlled to be lowered below the predetermined minimum value. An ECU 20 for outputting an air-fuel ratio control signal from a predetermined minimum reference value when the opening amount of the throttle valve is changed to be greater than or equal to a set reference value;

The actuator 30 is configured to inject fuel into the engine according to the air-fuel ratio control signal output from the ECU 20.

In the above, the vehicle operating state detection means 10 includes an oxygen amount detecting unit 11 for detecting an oxygen content in the exhaust gas discharged after combustion and outputting a predetermined electric signal;

A throttle valve opening degree detector 12 which detects an opening degree of a throttle valve whose opening / closing state is variable in association with an operation state of the driver's accelerator pedal and outputs a predetermined signal;

It includes a water temperature detection unit 13 for detecting a coolant temperature that varies according to the vehicle operating state and outputs a predetermined electric signal.

The air-fuel ratio control method among the engine warming up made by the above configuration will be described with reference to FIG.

When the vehicle starts to run, the ECU 20 determines whether the coolant temperature output from the vehicle driving state detecting means 10 belongs to the engine warm-up period (S100 and S110).

The ECU 20 determines that the engine is warmed up when the coolant temperature is positioned between 20 ° C. and 60 ° C. above.

Therefore, when driving in the warm-up state of the engine, the ECU 20 determines whether the air-fuel ratio control signal λ-Control for controlling the vehicle exhaust gas is output (S120).

When the air-fuel ratio control signal λ-Control for vehicle exhaust gas control is output in the above, the ECU 20 determines a predetermined reference value for which the control signal value Ti-LAM for air-fuel ratio control is set as shown in FIG. Min_Thb_LAM) or less is determined (S130).

When the control signal value Ti-LAM for the air-fuel ratio control is output below the predetermined reference value Min_Thb_LAM, the ECU 20 temporarily suspends the air-fuel ratio control and sets the predetermined minimum reference value for which the air-fuel ratio control signal value is set. The control signal is output to the actuator 30 so as to be maintained (S150).

Therefore, the actuator 30 injects fuel to the engine cylinder according to the control signal output from the ECU 20.

When the accelerator pedal is operated for acceleration during deceleration while driving the vehicle while controlling the air-fuel ratio as described above, the ECU 20 determines whether the change value of the throttle valve opening amount is changed to a predetermined reference value or more (S160).

When the throttle valve opening amount change value according to the driver's accelerator pedal operation is changed to a predetermined reference value or more, the ECU 20 receives a control signal for controlling the air-fuel ratio from the predetermined reference value Min_Thb_LAM set for the air-fuel ratio control. It outputs to the actuator 30 (S170).

Therefore, the actuator 30 injects fuel into the engine according to the air-fuel ratio control signal output from the ECU 20.

The above embodiments are described as the most preferred embodiments, and the present invention is not limited thereto, and the embodiments can be easily described from the above embodiments.

As described above, when the operating state of the engine falls within the warm-up period even when the vehicle is running, the air-fuel ratio control signal value is prevented from falling below a predetermined reference value, and the excessive fuel injection and / or the air-fuel ratio control The lean fuel injection has the effect of preventing the emission of harmful exhaust gas and the deterioration of the vehicle runability.

Claims (1)

In the engine air-fuel ratio control method of the vehicle, it is determined whether the operating state of the engine while driving is a warm-up section, and when the engine belongs to the warm-up section, it is determined whether an air-fuel ratio control signal (λ-Control) for vehicle exhaust gas control is output. Making a step; When the air-fuel ratio control signal λ-Control for controlling the vehicle exhaust gas is output in the step, determining whether the control signal value Ti-LAM for the air-fuel ratio control is output below a predetermined reference value Min_Thb_LAM. Wow; In this step, when the control signal value Ti-LAM for controlling the air-fuel ratio is output below the predetermined reference value Min_Thb_LAM, the control signal is temporarily suspended and the air-fuel ratio control signal value is set to maintain the predetermined minimum reference value. Outputting; Determining whether the change value of the throttle valve opening amount is changed to a predetermined reference value or more when the driver's accelerator pedal operation for acceleration during deceleration is made by driving the vehicle in the step and controlling the air-fuel ratio; When the throttle valve opening amount change value according to the driver's accelerator pedal operation is changed to a predetermined reference value or more, outputting a control signal for controlling the air-fuel ratio from the predetermined reference value Min_Thb_LAM set for the air-fuel ratio control to the actuator. Air-fuel ratio control method during the engine warm-up, characterized in that further comprising.