JPH09112283A - Opening/closing control method of intake control valve for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely secure stabilized combustion and promoted combustion by gas flow by closing an intake control valve, starting a timer for measuring the lapse time after starting an engine, and opening the intake control valve after a measured time attains a prescribed time, when the engine is started. SOLUTION: When an ignition switch is turned on, a tumble control valve 18 as an intake control valve is closed. In the case where it is judged whether an engine is started or not and in the result it is started, a timer 23 is started, and measuring of lapse time T after starting the engine is started. After starting engine, it is judged that an opening setting time Ts which is set beforehand is passed or not. In the case of passing, the tumble control valve 18 is opened, the timer 23 is reset, and opening/closing control operation of the intake control valve is completed. The tumble control valve 18 is closed after starting the engine, a time which is considered to necessitate the generation of gas fluid motion is set as a setting time, and combustibility at the time of engine starting can be surely improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the opening / closing of an intake control valve for an engine, and more particularly to controlling the opening / closing of an intake control valve provided in an intake system of an engine for producing a gas flow such as tumble or swirl in a combustion chamber. It is about the method.

[0002]

2. Description of the Related Art Intake intake control valves such as a tumble control valve and a swirl control valve that generate a gas flow in the combustion chamber in order to improve the stability of combustion in the combustion chamber of an engine, the promotion of combustion speed, and the improvement of fuel consumption. It is being installed in the aisle.

Such an intake control valve closes the intake passage to close the intake passage, changes the direction of air flow into the combustion chamber of the engine, and causes gas flow. Such an intake control valve increases the intake resistance in the intake system in the operating state, that is, in the closed state, and affects the securing of an appropriate intake air amount. Its proper opening and closing control is required to avoid the influence.

For example, in the intake device for an engine disclosed in Japanese Patent Laid-Open No. 63-215826, intake air temperature detecting means is provided in the intake system to detect the intake air temperature, and the intake air temperature is detected according to the intake air temperature. The opening degree of the intake control valve is adjusted by the control valve control means. That is, when the engine is operating in a predetermined low load region, the lower the intake air temperature, the more the opening degree of the intake control valve is corrected to the valve closing side. As a result, the lower the intake air temperature, the stronger the gas flow formation in the combustion chamber, and the enhancement of this gas flow corrects the deterioration of the fuel vaporization and atomization due to the lower intake air temperature. But I try to keep good flammability.

Further, in the intake device for an engine disclosed in Japanese Patent Laid-Open No. 1-106923, the intake air amount is detected, and when the intake air amount exceeds a predetermined value, the throttle is fully opened. In addition, under that condition, the intake control valve is operated according to the operation amount of the accelerator operation means. With this, when the intake air amount is relatively small, a high flow velocity of the intake air is secured, and the combustibility of the air-fuel mixture in the combustion chamber is improved. Further, as described above, when the intake air amount is a predetermined value or more, that is, a relatively large amount, the intake control valve is controlled so that the throttle is fully opened and the throttle action in the intake passage of the throttle valve is not substantially achieved. , Pumping loss at the beginning of the intake stroke is greatly reduced.

[0006]

When the engine is not warmed up immediately after the engine is started, the air-fuel ratio is set to the theoretical air-fuel ratio (A) in order to reduce HC (hydrocarbon) in the exhaust gas. Fuel injection is performed in a lean region (hereinafter, simply referred to as lean side) thinner than /F=14.7). Therefore, H which is an unburned component in the exhaust gas immediately after the engine is started.
In order to effectively reduce C and the like, it is particularly necessary to improve combustion efficiency using gas flow.

According to the engine intake system disclosed in Japanese Patent Laid-Open No. 63-215826, the opening degree of the intake control valve is adjusted only in a predetermined low load region. Therefore, in a state where the air-fuel ratio is set to the lean side and fuel injection is performed immediately after the engine is started, when the high load region is entered, the gas flow due to the operation of the intake control valve is not generated. Therefore, effective combustion cannot be achieved immediately after the engine is started, and the effectiveness of the exhaust gas reducing action is reduced. Further, in this conventional technique, the intake control valve is controlled only on the basis of the intake air temperature. However, even if the intake air temperature is low, the engine temperature may be sufficiently high. In this case, since the intake air temperature having a small heat capacity is less affected than the engine temperature, the gas flow by the intake control valve is not required but is controlled.

Next, in the engine intake system disclosed in Japanese Patent Laid-Open No. 1-106923, both the control of the throttle valve and the control of the intake control valve are performed based on the intake air amount.
There is a situation in which the control operation becomes complicated and it is necessary to equip both with a drive mechanism for controlling the throttle valve and the intake control valve, resulting in high cost.

The present invention has been made in view of the above various circumstances, and its object is to control the opening / closing of the intake control valve for generating an accurate gas flow in the combustion chamber without causing structural complication. The present invention provides a method for controlling the opening and closing of an intake control valve for an engine, which is capable of performing the above and improving the combustion, thereby preventing the influence on the engine operating condition and optimizing the exhaust gas purification action. .

[0010]

According to the method for controlling the opening and closing of the intake control valve for an engine according to the first aspect of the present invention, the intake control valve is closed from the time when the engine is started until a preset opening set time elapses. Therefore, the opening set time is surely stable from the start of the engine until the engine temperature rises sufficiently and the generation of gas flow to improve combustion efficiency is no longer necessary, It is possible to reliably ensure the promotion of combustion. Further, since the control is based on only the timer and is extremely simple, the simplification of the configuration of the control mechanism can be achieved.

According to the method for controlling the opening and closing of the engine intake control valve according to the second aspect, the predetermined lean state is judged by detecting the air-fuel ratio of the engine, and whether the lean state is based on the fuel cut operation. Since the operation of determining whether or not to perform is performed, the air control valve can be temporarily opened when the fuel cut is performed even before the opening set time has elapsed. Since the fuel injection is not performed when the fuel cut is performed, it is not necessary to close the intake control valve, so that the intake control valve is opened.

According to the method for controlling the opening and closing of the engine intake control valve according to the third aspect of the invention, the time required from the start of the engine to the effect of improving the combustibility by the gas flow is largely related to the engine temperature at the start of the engine. That is,
If the engine temperature at start-up is already high, the time required for gas flow is reduced. From this, the opening set time according to the first aspect is set based on the engine temperature, and an appropriate closed state time of the intake control valve is always secured.

According to a fourth aspect of the present invention, there is provided a method for controlling the opening and closing of an intake control valve for an engine, wherein a predetermined engine temperature (open set temperature) is set as a criterion for the necessity of gas flow, and whether it is less than or equal to the open set temperature. The intake control valve is closed or opened based on the above. Therefore, since the intake control valve is opened / closed based on the engine temperature, which is extremely important as a criterion for determining the necessity of improving the combustibility due to gas flow, the combustibility by the operation of the intake control valve at the time of engine start is ensured satisfactorily. Thus, optimization of the exhaust gas purification action is achieved.

According to a fifth aspect of the present invention, there is provided an engine intake control valve opening / closing control method in which, in addition to the temperature condition of the fourth aspect, a lapse condition of an opening set time after engine start is added as a selective condition. Therefore, the intake control valve is opened when the engine temperature becomes equal to or higher than the open set temperature or when the open set time elapses.

According to a sixth aspect of the present invention, there is provided a method for controlling the opening and closing of an intake control valve for an engine, which controls the opening and closing of the intake control valve based on the state of the throttle opening. The intake control valve is always opened when the opening degree is exceeded. As a result, the intake control valve closing operation that causes a decrease in the intake air amount due to an increase in intake resistance is not performed in the open state in which a large amount of intake air is required and a predetermined throttle opening or more.

According to a seventh aspect of the present invention, there is provided a method for controlling the opening and closing of an intake control valve for an engine, wherein the time period during which the combustibility must be reliably improved by the gas flow from the start of the engine, that is, the closed state maintaining time of the intake control valve. The intake control valve is kept closed until the time elapses. That is,
The control based on the throttle opening according to claim 6 is performed after the closed state maintaining time of the intake control valve has elapsed. However, when the throttle is fully opened when the maximum intake air amount is required, the intake control valve is opened as the highest priority, and priority is given to securing more intake air.

According to an eighth aspect of the present invention, there is provided a method for controlling the opening and closing of an intake control valve for an engine, wherein the throttle opening degree used in the control according to the sixth and seventh aspects is set according to one or both of the engine temperature and the engine speed. It was decided to set it. Therefore, the opening set opening, which is an appropriate reference according to the actual engine state, can be set as the opening / closing operation reference of the intake control valve. That is, as the engine temperature is higher or the engine speed is higher, the intake control valve is opened at a smaller throttle opening set opening degree. This means that the higher the engine temperature is, the less the gas flow is required, and therefore the opening operation of the intake control valve at the time of the smaller throttle opening is allowed. Further, when the engine speed is high, the engine temperature rises quickly, so that the opening setting opening can be smaller. By considering both of these conditions, it is possible to ensure more appropriate operation of the intake control valve, and as a result, the range in which good output is ensured by securing sufficient intake air is expanded.

In the method for controlling the opening and closing of the intake control valve for an engine according to the ninth aspect, a comprehensive judgment is made based on the engine temperature, a set opening degree of opening, and an elapsed time after the engine is started, and further fuel cut is performed. At this time, when the throttle is fully opened, the opening and closing of the intake control valve is controlled with these as priority conditions. That is, when the fuel cut is performed, the intake control valve is temporarily opened, and when the throttle is fully opened, it is opened thereafter. More precise opening / closing control can be performed by using various conditions that are largely related to the judgment of the opening / closing operation of the intake control valve as the judgment reference.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a schematic overall construction of an automobile engine in which an open / close control method for an engine intake control valve according to the present invention is used. As shown in the figure, the engine body 10 is provided with an engine water temperature sensor 12 for measuring the engine temperature. In addition, the engine body 10
A throttle valve 14 is provided in the intake system, and an injector 16 is provided downstream of the throttle valve 14. A tumble control valve 18, which is an intake control valve, is provided in one of the divided intake passages further downstream of the injector 16. The tumble control valve 18 is opened and closed by an electromagnetic actuator 20 which is an intake control valve driving means, and the electromagnetic actuator 20 is controlled by a control signal from an ECU (electronic control unit) 22. Further, a signal from a throttle opening sensor 24 for detecting the throttle opening and a signal from an O2 sensor 26 for detecting an air-fuel ratio provided in the exhaust system is input to the ECU 22, and further the detection from the water temperature sensor 12 is performed. Signals are also being input. The ECU 22 also has a timer 23 for measuring the elapsed time after the engine is started.

FIG. 2 shows the operation of the most basic embodiment of the present invention by taking the engine of the automobile shown in FIG. 1 as an example.

First, step (hereinafter simply referred to as "S")
At 101, the ignition switch is turned on. Here, the intake control valve is closed in S102. And
In S103, it is determined whether the engine has started. If not started (NO), the process returns to S102,
If the engine has started (YES), the timer 23 is started in S104, and the timer 23 starts measuring the elapsed time T after the engine is started. That is, the tumble control valve 18 is closed when the engine is started.

Next, in S105, after the engine is started, it is determined whether or not a preset opening time Ts has elapsed, and if it has not elapsed (NO), this determination is repeated. When the time has elapsed (YES), the tumble control valve 18 is opened in S106. Further, in S107, the timer is reset and the intake control valve opening / closing control operation ends. That is, the turnbull control valve 18 is opened until the engine is stopped and the next operation of S101 is performed.

As described above, it is possible to reliably improve the combustibility at the time of engine start by setting the time considered to be necessary to generate the gas flow by closing the tumble control valve 18 after the engine is started as the set time Ts. It is possible to optimize the exhaust gas purification action at the time of engine start, which is particularly important. This is an extremely simple control of opening and closing the intake control valve, which has never been done before, and simplification of the device is also achieved.

Next, FIG. 3 shows the operation of another embodiment. First, in S201, the ignition switch is turned on.
N is done. Then, in S202, it is determined whether or not the engine has started, and if it has not started yet (NO),
It returns to S201. Then, if it is started (YES), the timer 23 incorporated in the ECU 22 is started in S203. At the same time, S204
The intake control valve is closed at.

Then, in S205, it is judged whether or not the elapsed time T after the engine has started reaches the preset opening set time Ts, and when it reaches the opening set time Ts (YE
In S) and S206, the intake control valve is opened. And S
In 207, it is determined whether or not the engine has stopped. If it has stopped (YES), the process returns to S201.
Then, when the engine is not stopped (NO), the intake control valve opening / closing operation in this engine operation is completed, and the tumble control valve 18 is maintained in the open state.

If it is determined in S205 that the elapsed time after the engine has started has not opened and the set time Ts has not been reached, then in S208 the air-fuel ratio (A /
F) is detected. When it is determined in S209 that the air-fuel ratio is on the lean side (YES), it is determined in S210 whether or not fuel cut has been performed. Since the fuel cut is carried out under the control of the ECU 22, it is possible to judge the presence or absence of the fuel cut by detecting whether or not the instruction signal is generated. If the fuel cut operation is not performed (NO), it is determined in S211 whether or not the engine is stopped, and if the operation is not stopped (NO), the process returns to S205. On the other hand, when the engine is stopped (YES), the intake control valve opening / closing operation ends.

If it is determined in S210 that the fuel is cut (YES), the intake control valve is opened in S214. If it is determined in S211 whether the engine is stopped and the operation is not stopped, the operation is repeated in S205.
Will be returned to. Therefore, the tumble control valve 18 is opened while the fuel cut state continues until the elapsed time T after the engine starts reaches the set time Ts.
In the re-operation from S205, if the determination in S209 remains lean, the tumble control valve 18 once opened in S214 is closed again (S215). That is,
When there is a fuel cut within the open set time Ts and the air-fuel ratio is in the lean state requiring gas flow, the tumble control valve 18 is temporarily opened.

When it is determined in S209 that the air-fuel ratio is not lean (NO), the intake control valve is opened in S212.

As described above, since the condition based on the detection of the air-fuel ratio is added in addition to the elapse of time, even immediately before the elapse of the set opening time Ts, the lean state at the time of engine start is immediately canceled. The tumble control valve 18 is opened to temporarily open the tumble control valve 18 when the fuel is cut even in the lean state.

Therefore, when the gas flow becomes unnecessary, the intake control valve is opened immediately to avoid unnecessary increase in intake resistance.

FIG. 4 illustrates the operation of the basic embodiment based on engine temperature.

First, in step S301, the ignition switch is turned on. Then, the engine temperature W is detected in S302. The engine temperature W is determined by detecting the engine water temperature with the water temperature sensor 12.

Then, in S303, it is judged whether or not the engine water temperature W exceeds a preset opening set temperature Ws, and if it exceeds (YES), the intake control valve is opened in S304. And if it does not exceed (N
O), the intake control valve is closed in S305. In this state, it is determined in S306 whether the engine has been started, and if the engine is not yet started (NO), S
Return to 302.

Next, when it is determined in S306 that the engine has been started (YES), the opening set temperature Ws set in advance and the engine water temperature W are compared in S307, and the set temperature Ws is set to the engine water temperature. When W exceeds (YE
In steps S) and S308, the tumble control valve 18 is opened. If it is already opened in S304, it is continued. If the set temperature Ws is not exceeded (NO), S30
If it is determined whether the engine is stopped or not in 9 and the operation is continued, the process returns to S307 and is stopped (YE
The opening / closing control ends in S).

In this embodiment, the ignition switch O
After the N operation, the tumble control valve 18 is always opened and closed based on the engine water temperature W, and the intake control valve is opened and closed based on the engine temperature which is closely related to the combustibility. The intake control valve can be closed only when gas flow is truly required, and an appropriate intake control valve can be used.

FIG. 5 shows the operation of yet another embodiment.

First, the operations from S401 to S406 are the same as the operations from S301 to S306 shown in FIG. 4, and the description thereof will be omitted. If it is determined in S406 that the engine has been started (YES), it is determined in S407 whether the tumble control valve 18 has already been opened (YES), and in S408 a timer is set. Is reset and the control ends.

On the other hand, if the intake control valve is not opened in S407 (NO), the timer 23 is started in S409 and the elapsed time T after the engine is started is measured. And
In S410, the opening set time Ts is calculated based on the engine water temperature W detected in S402. This calculation operation is calculated by a map of the engine water temperature W and a preset time or by a linear expression.

Next, it is judged whether or not the opening set time Ts set in S411 has passed and if not (NO), the repeat timer count is performed (S41).
2). When the time has elapsed (YES), the intake control valve is opened in S413. Furthermore, in S408, timer 2
3 is reset and the opening / closing control operation of the intake control valve is completed.

In the present embodiment, the engine temperature and the elapsed time are combined and the time for which the intake control valve is kept closed after the engine is started is set based on the state of the engine water temperature W. . That is, in consideration of the engine temperature which has an important effect on the combustibility, the set time for keeping the intake control valve closed is shortened when the engine temperature is high.

In the comparison of the engine water temperature W and the set opening temperature Ws in S403, not only whether the set opening temperature Ws is exceeded, but also when the set temperature Ws is not exceeded, the temperature is below the predetermined temperature. In such an extremely low temperature state, the control by the tumble control valve 18 is not preferable, so the tumble control valve 18 may be left open and only the control by the air-fuel ratio may be performed. That is, in that case, it is determined that Wx>W> Ws, and YES
In the case of, the tumble control valve 18 is opened. Wx means a low temperature limit temperature that does not utilize the action of the tumble control valve 18.

FIG. 6 shows another embodiment, in which a basic opening / closing operation of the intake control valve based on the throttle opening A is shown. As shown, in S501, it is determined whether or not the ignition switch is turned on. ON
When operated (YES), the throttle opening A is detected. Then, it is determined whether or not the throttle opening A detected in S503 exceeds a preset opening setting As, and if it exceeds, the intake control valve is opened in S504, and if not exceeded. In (NO), the closed state of the intake control valve is maintained in S505.

Although the determination of whether or not the engine is started is not shown in this figure, the opening and closing of the tumble control valve 18 is similarly performed after the engine is started by comparing the throttle opening A with the set opening setting As. It is controlled. Further, when the throttle opening A exceeds the opening set opening As and the tumble control valve 18 is once opened, the open state is maintained until the engine is stopped and the opening / closing control operation is performed again. This is in consideration of the normal driving condition of a vehicle.If the throttle opening exceeds the opening set opening set after the engine is started, the engine temperature has risen sufficiently and the throttle opening This is because it is not necessary to close the intake control valve again even when the degree returns.

FIG. 7 shows another embodiment.

First, in step S601, it is determined whether the ignition switch is in the ON state. If the ignition switch is not in the ON state (NO), the process returns. If it is turned on, the intake control valve is first closed in S602.

Then, the engine water temperature W is detected in S603, and the engine speed is detected in S604.

Further, if it is determined in S605 that the engine has been started and the engine has not been started yet (NO), the routine returns. If it has been started (YES), S606.
At, the timer for measuring the elapsed time T is started, and S
At 607, a reference throttle opening set opening As is calculated based on either or both of the engine water temperature W and the engine speed S. Note that maps for calculating the opening set opening degree As are shown in FIGS. 8 and 9.

FIG. 8 is a one-dimensional map of the set opening As with respect to the engine temperature W. When the engine water temperature is -10 ° C. or less as shown in the figure, the control by opening and closing the intake control valve is not appropriate. The set opening As becomes smaller as the temperature decreases. However, when the temperature is -10 ° C or higher, the opening / closing control of the intake control valve according to the present invention is applied, and the opening set opening degree A increases as the engine water temperature W increases.
It is understood that s is set at a small angle.

FIG. 9 shows the engine water temperature W and the engine speed S.
That is, a map is shown in which the throttle opening set opening As is determined based on a two-dimensional map with the engine speed. As can be seen from the figure, the set opening As is set smaller as the engine speed increases. This is because it is considered that the engine temperature rises faster when the engine speed is higher.

Next, in step S608, the current throttle opening A is detected. Further, in S609, it is determined whether the elapsed time T exceeds the closed state maintaining time Tc for maintaining the closed state of the intake control valve. This closed state maintenance time Tc
Is a condition that is prioritized and applied to the opening / closing control of the intake control valve based on the normal throttle opening A. During this closed state maintaining time Tc, even if the throttle opening exceeds the set opening As, the intake air intake The control valve is never opened. However, as will be described later, when the throttle opening is fully opened, priority is given to ensuring sufficient intake air and opening.

When it is determined in S609 that the closed state maintaining time Tc has elapsed (YES), it is determined in S610 whether or not the throttle opening A has exceeded the opening set opening As (if not) ( If NO, the tumble control valve 18 is kept closed in S611 and is exceeded (YE).
In S), the tumble control valve 18 is opened in S612.

If the closed state maintaining time Tc has not elapsed in S609 (NO), it is determined in S613 whether the throttle opening A is in the fully open state. And
If it is in the fully open state (YES), the tumble control valve 18 is opened in S614. When it is determined in S613 that the intake control valve is not in the fully open state, the closed state of the intake control valve is maintained in S615.

In the case of S611 and S615 in which the intake control valve is kept closed, it is determined in S616 whether the ignition switch is in the ON state, and if it is in the ON state, the process returns to S609 again. When the ignition switch is not turned on (NO)
To return to the start. Note that S612 and S
When the intake control valve 614 is opened, the opening / closing control ends and the process returns to the start.

Next, FIG. 10 shows a case where the throttle opening set opening A determined based on the engine water temperature W is set to two types based on the values of W.

As shown in the drawing, when the determination in S609 shown in FIG. 7 is YES, that is, when it is determined that the closed state maintaining time Tc has elapsed, the engine water temperature W and the switching point temperature are determined in S701. A certain Wc is compared. If the engine water temperature W is lower than the switching point temperature Wc (YES), S7
At 02, a relatively small opening setting opening As1 is set. On the other hand, when the determination of W <Wc is NO in S701, the comparatively large opening set opening As is determined in S703.
2 is set. Then, S704 and S705, respectively.
At throttle opening A and opening set opening As1, A
The comparison with s2 is performed. If A is larger (NO), the tumble control valve 18 is opened, and if A is smaller (YES), the tumble control valve 18 is kept closed.

As described above, in the embodiment of FIGS. 7 and 10, the tumble control valve is opened only when the throttle is fully opened until the closed state duration Tc determined based on the engine water temperature W at the engine start elapses. Open 18 and continue after that. After the closed state duration time Tc has elapsed, the tumble control valve 18 is opened and closed based on the throttle opening set opening degree As, and good control is performed in consideration of the engine water temperature W at the start.

FIG. 11 shows various measured values in the operation of the above embodiment with a common time axis. FIG. 4A shows a change in the engine water temperature W in the process of stopping the engine after the closed state maintaining time Tc has passed since the ignition switch was turned on. As shown in the figure, it rises from the start of the engine, stabilizes at a certain value, and continues until the engine stops.

In FIG. 7B, the tumble control valve 18 is opened,
The closed state is shown. FIG. 3C shows a state in which the timer 23 measures the elapsed time T after the engine is started, and is reset by the opening operation of the tumble control valve 18. FIG. 6D shows the opening set opening As set based on the change in the throttle opening A (solid line) and the engine water temperature W.
1, As2 (chain line) is shown. In this embodiment, the water temperature Wo is used for switching. FIG. 6E shows changes in vehicle speed corresponding to the throttle operation.

Incidentally, FIG. 6F shows the control operation of the air-fuel ratio which will be described later, and a negative correction value SDLEAN for controlling the lean side until the tumble control valve 18 is opened is added. The negative correction value SDLEAN is a correction value for reducing the injection amount of the fuel injected from the injector 16, the details of which will be described later.

As shown in the figure, the closed state duration time Tc
Before the passage of the throttle opening A exceeds the set opening As1 or As2, the tumble control valve 18 is not opened (in the case of the embodiment of FIG. 6 described above or FIG. 12 described later, the throttle opening A Is opened and the tumble control valve 18 is opened when the set opening As is exceeded. However, as shown in the drawing, when the throttle is set to a state close to full open at the time of P1, and the acceleration is performed next, the fuel cut operation is performed, but in that case, the tumble control valve 18 is temporarily opened (the same). B in Figure (B)
-1).

When the throttle is fully opened (P2 in FIG. 3D), the tumble control valve 18 is opened thereafter even before the closed state duration time Tc has elapsed (b- in FIG. 2B). 2).

FIG. 12 is an operation flowchart showing still another embodiment. As shown in the figure, after the ignition switch is turned on (not shown), the engine water temperature W is detected in S801 and the throttle opening A is detected in S802. Then, in S803, the engine water temperature W is compared with the opening set temperature Ws. If W is higher (NO), the tumble control valve 18 is opened in S804. This is because there is less need for gas flow. On the other hand, S8
If W is lower in 03 (YES), the throttle opening A is compared with the opening set opening As in S805, and if A is larger (NO), the tumble control valve 18 is opened in S804.

If it is determined in S805 that A is smaller (YES), the tumble control valve 18 is closed in S806 for the time being. Next, in S807, it is determined whether or not the engine has been started, and if not (N
O) The tumble control valve 18 is opened in S804. If it is determined in S807 that the engine has been started (YE
In steps S) and S808, the timer 23 is started.

In step S809, the opening set time Ts is determined based on the engine water temperature W. In S810, when it is determined that the elapsed time T is equal to or longer than the opening set time Ts (YES), the opening operation of the S804 tumble control valve 18 is performed. On the other hand, in S810, the elapsed time T opens and the set time T
When s is not exceeded (NO), it is determined in S811 whether the fuel cut has been performed.

If it is determined that the fuel cut has been made (YES), the action of the intake control valve is not necessary, so the tumble control valve 18 is opened in S812. Then, in S813, it is determined whether or not the fuel cut state is recovered. If it is determined that the fuel cut state is recovered, that is, if the fuel supply is restarted (YES), the tumble control valve 18 is closed again in S814. On the other hand, S813
If it is determined that the fuel cut has not been recovered,
The process also returns to the determination in S810. That is, the closed state maintenance time T
Before the passage of c, the tumble control valve 18 is opened until the fuel cut is recovered.

When it is determined in S811 that the fuel is not cut (NO), another priority condition is determined in S815 whether the throttle is fully opened, and when it is fully opened (YES), the tumble control valve 18 is It is opened in S804. If not fully opened (NO), the current throttle opening A is compared with the opening set opening As as a determination based on the normal throttle opening A in S816, and A is A.
If s or more (YES) in S804, the tumble control valve 1
8 is opened and returned if As has not been reached.

FIG. 13 shows various measured values in the operation of the above embodiment with a common time axis.
It corresponds to 1. FIG. 9A shows a change in the engine water temperature W in the process of stopping the engine after the opening set time Ts (which has a different priority from the closed state maintaining time Tc) has elapsed since the ignition switch was turned on.

In FIG. 7B, the tumble control valve 18 is opened,
In the closed state, (C) of the figure shows a state in which the elapsed time T after the engine is started is measured by the timer 23. FIG. 6D shows the change in throttle opening A (solid line) and the set opening opening Ast (chain line). The opening set opening Ast is determined based on a two-dimensional map (see FIG. 9) of the engine water temperature W and the engine speed S, that is, the engine speed, using a 16-lattice table. FIG. 6E shows changes in vehicle speed corresponding to the throttle operation. Note that FIG. 6F shows the control operation of the air-fuel ratio, and a negative correction value SDLEAN for controlling the lean side until the tumble control valve 18 is opened is added.

As can be seen from the figure, in the present embodiment, the tumble control valve 18 is opened when the throttle opening A reaches the set opening Ast even before the opening set time Ts has elapsed (the same as above). Figures B and D). As shown in the drawing, the opening set time Ts of this embodiment is shorter than the closed state maintaining time Tc which is prioritized over the control condition by the throttle opening A shown in FIG. This is because those set times are determined based on the engine water temperature W at the time of engine start. In this figure, the engine water temperature W at start is shown in FIG.
Since it is higher than the case shown in 1, it is shorter.

Also in this embodiment, for example, if the throttle is fully opened before the opening set time Ts elapses, the tumble control valve 18 is opened thereafter, or if the fuel is cut, the tumble control valve 18 is opened. 18 is temporarily opened.

Next, FIG. 14 shows the operation of one embodiment in which the air-fuel ratio control is also performed when the gas flow is generated by the closing operation of the tumble control valve 18.

First, in step S901, it is determined whether or not the ignition switch is turned on. If NO, this determination is repeated. In the case of YES, an operation of closing the tumble control valve 18 is performed as an initial operation in S902, and at the same time, an operation of detecting the engine temperature (engine water temperature W) is also started in S903. Further, in S904, a calculation for adding a negative lean correction value SDLEAN for securing a lean state at the time of engine start is performed to COEF for calculating the fuel injection amount Ti which is the basis of the air-fuel ratio control. . That is, Ti = Tp × LMD × CO
Lean correction value S for calculating EF + SDLEAN
The calculation of DLEAN is performed. Here, Tp is the basic fuel injection amount, LMD is the air-fuel ratio feedback correction value,
COEF is an air-fuel ratio correction coefficient.

Then, in S905, it is judged whether or not the engine is started, and if it is not started (NO), the operation is returned and the above operation is repeated. If it has been started (YES), the timer 23 is started in S906. Next, in S907, it is determined whether or not the opening set time Ts which is previously determined based on the engine water temperature W has elapsed. If it has passed (YES), the correction by the lean correction value SDLEAN is canceled in S908. This is because the tumble control valve 18
This is because the fuel injection amount correction on the lean side is stopped in response to this because the gas flow is also opened and the gas flow disappears.

Next, in S909, the throttle opening A is detected, and in S910, the opening set opening A determined in advance is determined.
Compare with s. If A is large (YES), as in the above embodiment, the tumble control valve 18 is opened in S911. When A is small (NO), the closed state of the tumble control valve 18 is maintained in S912, and the return operation is performed in S913 by determining the state of the ignition switch.

When it is determined in S907 that the opening set time Ts has not elapsed (NO), the throttle opening A is detected in S914, and the throttle opening A is compared in S915. Then, as in the case of S910, when A is large (YES), in S916, the tumble control valve 1
8 is opened. In this case, since the opening set time Ts has not elapsed, the addition of the lean correction value SDLEAN is not canceled immediately, and the lean correction value SDLEAN2 with the tumble control valve 18 opened is used. On the other hand, when A is small (NO), the closed state of the tumble control valve 18 is maintained in S917, and in this case, the air-fuel ratio control is performed by adding the lean correction value SDLEAN set in S904. Then, after S917 and S918, the state of the ignition switch is determined in S913 similarly to the case after S912, and if it is off (NO), the process returns to START, and if it is on (YES), the process returns to S907.

The lean correction value SDLEA of this embodiment is used.
N is determined by a one-dimensional map corresponding to the engine water temperature W as shown in FIG. 15A or a two-dimensional map of 16 grids of the engine water temperature W and the engine load as shown in FIG. 15B. It is determined. Further, FIG. 6C shows a numerical value of SDLEAN2 which is a lean correction value when the tumble control valve 18 is opened before the opening set time Ts has elapsed. In each figure, the value of SDLEAN is shown in hexadecimal.

In the present embodiment, the tumble control valve 1 based on the elapsed time T after starting the engine and the throttle opening A is used.
The open / close control of No. 8 is performed and the lean operation can be favorably performed for a predetermined period after the engine is started, and the exhaust gas purifying action is optimized and the combustion is improved.

[0079]

As described above, according to the method for controlling the opening and closing of the intake control valve for an engine according to the present invention, the generation of gas flow in the combustion chamber at the time of starting the engine can be performed without complicating the structure. Can be accurately controlled, and an appropriate exhaust gas purification action can be achieved while preventing adverse effects on the engine operating condition.

[Brief description of the drawings]

FIG. 1 is a schematic overall configuration diagram of an automobile engine in which an open / close control method for an engine intake control valve according to the present invention is used.

FIG. 2 is a flowchart showing a basic embodiment of the present invention.

FIG. 3 is a flow chart showing one embodiment of the present invention.

FIG. 4 is a flowchart showing one embodiment of the present invention.

FIG. 5 is a flowchart showing a basic embodiment of the present invention.

FIG. 6 is a flowchart showing one embodiment of the present invention.

FIG. 7 is a flow chart diagram showing an embodiment of the present invention.

FIG. 8 is a map diagram for determining the opening set opening used in the embodiment.

FIG. 9 is a map diagram for determining an opening set opening used in the embodiment.

FIG. 10 is a flowchart showing a modification of the embodiment shown in FIG.

11 (A) to (F) are time charts showing changes in various measured values in the operation of the embodiment.

FIG. 12 is a flowchart showing one embodiment of the present invention.

13A to 13F are time charts showing changes in various measured values in the operation of the embodiment.

FIG. 14 is a flowchart of an operation when the air-fuel ratio control operation is added to the one embodiment of the present invention.

15A to 15C are map diagrams for calculating a lean correction value used for the air-fuel ratio control operation in the embodiment of FIG.

[Explanation of symbols]

 10 Engine Body 12 Water Temperature Sensor 18 Tumble Control Valve 22 ECU 24 Throttle Opening Sensor

Claims (9)

[Claims] 1. A method of opening and closing an intake control valve for an engine, which is provided in an intake system of an engine and is opened and closed by an intake control valve drive means to generate a gas flow in a combustion chamber during a closing operation. An engine characterized by starting a timer for measuring an elapsed time after starting when the engine is started and closing the intake control valve after the time measured by the timer reaches a predetermined opening set time Control method for opening and closing intake control valve for automobile. 2. Before the opening set time is reached, it is determined whether the air-fuel ratio of the engine is in a predetermined lean state and, if lean, is due to a fuel cut operation, and the fuel cut It is characterized in that it keeps a closed state in a lean state that does not depend on operation, temporarily opens the intake control valve in a fuel cut state, and opens the intake control valve after a non-lean state. The method for controlling opening and closing of an intake control valve for an engine according to claim 1. 3. The engine temperature at the time of starting the engine is measured, and the opening set time is set as a time that becomes shorter as the engine temperature becomes higher, based on the measured engine temperature. 3. An open / close control method for an engine intake control valve according to either 1 or 2. 4. A method of opening and closing an intake control valve for an engine, which is provided in an intake system of an engine and is opened and closed by an intake control valve driving means to generate a gas flow in a combustion chamber at the time of a closing operation. The temperature is measured, and the intake control valve is closed when the measured engine temperature is lower than a predetermined opening set temperature determined as a reference of necessity of the gas flow, and after the opening set temperature is reached or higher. Is a method for opening and closing an intake control valve for an engine, wherein the intake control valve is opened. 5. When the engine temperature is lower than the opening set temperature at the time of starting the engine, the intake control valve is closed, and a timer for measuring an elapsed time after the engine is started is started. 5. The opening / closing of the intake control valve for an engine according to claim 4, wherein the intake control valve is opened when the temperature exceeds the opening set temperature or after the elapsed time reaches a predetermined opening set time. Control method. 6. A method of opening and closing an intake control valve for an engine, which is provided in an intake system of an engine and is opened and closed by an intake control valve drive means to generate a gas flow in a combustion chamber at the time of a closing operation. The throttle opening is detected, and when the detected throttle opening is less than a predetermined opening set opening predetermined as a reference of the necessity of the gas flow, the intake control valve is closed and the opening setting open is performed. A method for controlling opening and closing of an intake control valve for an engine, characterized in that the intake control valve is opened after the temperature exceeds a certain degree. 7. When the engine is started, a timer that closes the intake control valve and measures the elapsed time after the engine is started is started, and the throttle opening setting opening is used as a reference except when the throttle opening is fully opened. Prior to opening / closing control of the intake control valve, the closed state of the intake control valve is maintained when the time measured by the timer is less than a predetermined closed state maintaining time, and the throttle is maintained after the closed state maintaining time has elapsed. The opening / closing control method of the intake control valve for an engine according to claim 6, wherein the opening / closing operation control of the intake control valve is performed based on the opening set opening degree. 8. One or both of an engine temperature and an engine speed is measured, and the opening set opening degree of the throttle and the closed state maintaining time are either one of the measured engine temperature and engine speed or The opening / closing control method for an intake control valve for an engine according to claim 6 or 7, wherein the opening degree is set based on both, and the opening degree is smaller as the engine temperature is higher or the engine speed is higher. 9. A method of opening and closing an intake control valve for an engine, which is provided in an intake system of an engine and is opened and closed by an intake control valve drive means to generate a gas flow in a combustion chamber at the time of a closing operation. And the elapsed time after the engine is started, and based on the engine temperature at the time of starting the engine, the throttle opening set opening and the opening set time which is the elapsed time which are the reference for opening and operating the intake control valve are determined. If the engine temperature reaches the opening setting temperature, the throttle opening reaches the opening setting opening, or the elapsed time reaches the opening setting time, intake control is performed thereafter. Open the intake control valve from the closed state to the open state and temporarily open the intake control valve if the fuel cut is performed even if those conditions are not satisfied. There opening and closing control method for an engine intake control valve, characterized in that the subsequent open state when it is fully opened.