JP3436173B2 - Intake control device for internal combustion engine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake control device for an internal combustion engine, and more particularly to an electronically controlled throttle valve that is provided with an electronically controlled throttle valve whose opening is set independently of the accelerator pedal depression amount. The present invention relates to an intake control device for an internal combustion engine in which valve closing control is performed.

[0002]

2. Description of the Related Art In recent years, with the development of computers, electronically controlled internal combustion engines have been put into practical use in order to electronically optimally control the rotational speed of the internal combustion engine. As such electronic control of the internal combustion engine, for example, fuel injection amount control, ignition timing control, control of intake / exhaust valve opening timing, etc. have been preceded, and subsequently, electronic control of the throttle valve is also put into practical use. Entering the stage. In an internal combustion engine that electronically controls the opening of the throttle valve, the opening of the throttle valve can be set regardless of the depression amount of the accelerator pedal.

Therefore, by closing the intake passage at the time of starting the engine using the electronically controlled throttle valve, the amount of intake air at the time of starting can be reduced and the negative pressure of the intake pipe can be increased to promote the vaporization of fuel. Proposed. This is because in the electronically controlled internal combustion engine, the fuel injection valve is installed in the intake passage near each combustion chamber, so the fuel may not be sufficiently atomized at the time of starting, and at this time the startability deteriorates. This is to prevent this.

As described above, by closing the electronically controlled throttle valve at the time of starting the engine, the intake air amount is reduced and the intake pipe negative pressure is increased to promote the vaporization of fuel. There is one disclosed in the publication. In Japanese Patent Laid-Open No. 9-324677, an intake control device for an internal combustion engine is provided with a control means for closing the intake passage with a throttle valve at the time of starting the engine and opening the throttle valve after the start of the engine is completed. At the time of engine start, the elapsed time after the start of fuel injection is measured, and when this elapsed time exceeds the predetermined time, the throttle valve is opened to the predetermined opening and the fuel injection amount is adjusted even before the completion of the engine start. It is disclosed to increase the dose.

[0005]

However, in the technique disclosed in Japanese Unexamined Patent Publication No. 9-324677, when the throttle valve is opened, if the opening change of the throttle valve is large, the change of the intake air amount becomes large and the empty air amount becomes large. There was a problem that the fuel ratio control could not follow up, which affected startability and deteriorated emission.

Therefore, the present invention relates to a multi-cylinder internal combustion engine in which an electronically controlled on-off valve is provided in the intake passage, and which controls the closing of the electronically controlled on-off valve when the engine is started,
When shifting from the electronically controlled on-off valve closing control to the valve opening control,
An object of the present invention is to provide an intake control device for an internal combustion engine, which can suppress an excessive change in intake air amount, improve engine startability, and prevent emission deterioration.

[0007]

In order to achieve the above object, the invention according to claim 1 operates an electronically controlled opening / closing valve at the time of starting to close the intake passage, thereby increasing the intake pipe negative pressure at the time of starting. In an intake control device for an internal combustion engine that performs valve closing control at startup to atomize fuel, the degree of opening of an electronically controlled on-off valve leaves a slight gap between it and an intake passage when the ignition switch is turned on. It is consumed by the internal combustion engine after the engine is cranked with the first opening control means for controlling the first opening close to the state and the opening / closing valve at the first opening. The intake air amount calculation means for calculating the air consumption amount, and the intake air amount in the volume of the intake passage from the downstream side of the electronically controlled opening / closing valve to the front of the intake valve of each cylinder, and the value of the air consumption amount Calculate the transfer coefficient from the consumption rate of the intake air amount based on A transfer coefficient calculating means, a transfer air amount calculating means for calculating the transfer air amount from the intake air amount and the transfer coefficient required after completion of the valve closing control at startup, and the transfer air amount. And a second opening control means for comparing the second opening and the first opening of the opening / closing valve for flowing the flow rate and controlling the opening of the opening / closing valve to the larger opening. Is characterized by.

The invention according to claim 2 for attaining the above object is the invention according to claim 1, wherein when the second opening control means exceeds a predetermined time after the start of the engine start. It is characterized by stopping the operation. Note that the above-mentioned gap at the first opening can be a gap that can secure a minimum idle air flow rate value, and the valve closing control at the time of startup of the present invention is performed so that the engine temperature falls within a predetermined temperature range. It can be activated only at certain times.

According to the present invention, when the electronically controlled on-off valve which is closed at the time of starting the engine is opened, the opening degree of the electronically controlled on-off valve and the starting coefficient based on the consumption ratio of the intake air amount Since it increases smoothly based on the product with the intake air amount required after the end of the valve closing control at the time, it is possible to suppress an excessive change in the intake air amount when shifting from the valve closing control to the valve opening control. The startability is improved and the deterioration of emission is prevented.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail based on specific examples with reference to the accompanying drawings. FIG. 1 schematically shows an electronically controlled fuel injection type multi-cylinder internal combustion engine 1 including an intake control device according to an embodiment of the present invention. In FIG. 1, an intake passage 2 of an internal combustion engine 1 is provided with a throttle valve 3 downstream of an air cleaner (not shown), and one end of a shaft of the throttle valve 3 is a throttle that is an actuator for driving the throttle valve 3. A motor 4 is provided, and a throttle opening sensor 5 for detecting the opening of the throttle valve 3 is provided at the other end. That is, in the throttle valve 3 of this embodiment, the opening degree of the accelerator pedal 14 is detected by the accelerator opening degree sensor 15, and the ECU (described later) together with the opening degree and each control signal of the electronic control device attached to the engine. The engine control unit) 10 determines an optimum throttle opening degree, and is incorporated in an electronically controlled throttle (hereinafter simply referred to as an electronic throttle) which is opened / closed by a throttle motor 4. For electronic throttle, throttle valve 3
When the opening command value of is input from the ECU 10, the throttle motor 4 responds to the command value and causes the throttle valve 3 to follow the command opening.

An atmospheric pressure sensor 18 is provided upstream of the throttle valve 3 in the intake passage 2, and a surge tank 6 is provided downstream thereof. A pressure sensor 7 for detecting the pressure of intake air is provided in the surge tank 6. Furthermore, surge tank 6
A fuel injection valve 8 for supplying pressurized fuel from the fuel supply system to the intake port is provided on the downstream side of each cylinder. The output of the throttle opening sensor 5 and the output of the pressure sensor 7 are input to the ECU 10 incorporating a microcomputer.

A water temperature sensor 11 for detecting the temperature of the cooling water is provided in the cooling water passage 9 of the cylinder block of the internal combustion engine 1. The water temperature sensor 11 generates an electric signal of analog voltage according to the temperature of the cooling water. The exhaust passage 12 has three harmful components HC and C in the exhaust gas.
A three-way catalytic converter (not shown) for purifying O and NOx at the same time is provided, and an O ₂ sensor 13 which is a kind of air-fuel ratio sensor is provided in the exhaust passage 12 on the upstream side of the catalytic converter. There is. The O ₂ sensor 13 generates an electric signal according to the oxygen component concentration in the exhaust gas. The outputs of the water temperature sensor 11 and the O ₂ sensor 13 are output from the ECU 10.
Entered in.

Further, the ECU 10 is provided with a signal indicating the amount of depression of the accelerator pedal (accelerator opening signal) from the accelerator opening sensor 15, and a key position signal (accessory position, from the ignition switch 17 connected to the battery 16).
ON position, starter position), a crank dead center signal TDC from a crank position sensor 21 provided near a timing rotor 24 integrated with a crankshaft timing pulley attached to one end of the crankshaft, and a crank at a predetermined angle. The angle signal CA and the temperature of the lubricating oil from the oil temperature sensor 22 are input. The ring gear 23 provided on the other end of the crankshaft is rotated by the starter 19 when the engine 1 is started.

The engine speed Ne is determined by a predetermined crank angle signal C
It is obtained by measuring the interval (time) of A. The timing rotor 24 is provided with signal teeth 25, and has 34 teeth including two toothless portions 26 for detecting the top dead center. The crank position sensor 21 can be composed of an electromagnetic pickup and outputs a crank rotation signal every 10 °. The crank position sensor 21 can accurately detect the top dead center by detecting the signal at the toothless portion 26. Further, the cylinder in which the fuel injection of the internal combustion engine is executed can be determined by the signal from the crank position sensor 21 and the signal from the cam position sensor (not shown).

In a conventional internal combustion engine, a starter 19 which is generally composed of a DC direct-winding motor is connected to the battery 16 via a starter switch which is turned on when the ignition switch 17 is in the starter position. Therefore, when the ignition switch 17 is turned on and then the ignition switch 17 is set to the starter position, the starter 19 is activated and the engine 1 is activated. Then, when the engine 1 starts to operate, the ECU 10 is energized to start a program, take in the output from each sensor, and control the throttle motor 4 for opening and closing the throttle valve 3, the fuel injection valve 8, or other actuators. . The ECU 10 includes an A / D converter that converts an analog signal from various sensors into a digital signal, and an input / output interface 10 through which an input digital signal from each sensor and a signal for driving each actuator come in and out.
1. CPU 102 for performing arithmetic processing, ROM 103 and RA
A memory such as M104 and a clock 105 are provided, and these are connected to each other by a bus 106. E
Since the configuration of the CU 10 is publicly known, further description will be omitted.

On the other hand, in this embodiment, the starter 19 is not directly connected to the battery 16 but is connected to the battery 16 via the starter drive circuit 20. And
The starter drive circuit 20 operates the starter 19 to the battery 1 when the starter signal ST from the ECU 10 is not input.
It is designed not to connect to 6. In this embodiment, when the engine 1 is started, the throttle valve 3 is temporarily closed to substantially close the intake passage 2 and a negative pressure is generated on the downstream side of the throttle valve 3 to improve the engine startability. There is. On the other hand, when the engine 1 is stopped, the throttle valve 3 is not in the fully closed position and is slightly open. Therefore, when the engine 1 is stopped, the inside of the intake passage 2 of the throttle valve 3 is at atmospheric pressure.

Therefore, when starting the engine 1, it is necessary to drive the throttle motor 4 to control the throttle valve 3 to the fully closed position. The throttle valve 3 here
The fully closed position 3 is a position where the throttle valve 3 and the intake passage 2 do not collide with each other, but a position where a slight gap is opened. In this embodiment, this gap has a minimum ISC flow rate ISCmin. It is a gap that flows. Therefore, E
The CU 10 has the ignition switch 1 as described above.
The key position signal from 7 and the throttle opening signal from the throttle opening sensor 5 are input.

2 to 5 are flowcharts showing the procedure of the drive control of the throttle valve 3 executed by the ECU 10 and the fuel injection control when the engine 1 having the above-described structure is started. Will be explained.
FIG. 2 is a flowchart showing a procedure for setting the flag FTHVC for executing the closing control of the electronically controlled throttle valve 3.
The routine shown in FIG. 2 is executed only at the time of starting the engine 1 in the initial routine at predetermined time intervals, for example, every several ms.

In this control, first, at step 201, the engine water temperature THW detected by the water temperature sensor 11 described in FIG. 1 is read. In the following step 202, it is determined whether or not this water temperature is within a predetermined temperature range of A ° C to B ° C. Step 20 when the water temperature THW is not within this range
4, the throttle valve closing control execution flag FTHVC is set to "0", and this routine is ended. On the other hand, the water temperature TH
When W is within this range, the routine proceeds to step 203, where the throttle valve closing control execution flag FTHVC is set to "1".
Then, this routine is finished. When the throttle valve closing control execution flag FTHVC is "1", it indicates that the throttle valve closing control is performed.

In this embodiment, the throttle valve closing control execution flag FTHVC is set to "0" and the throttle valve closing control is performed at a temperature where the water temperature THW is less than A ° C which is extremely low temperature and exceeds B ° C which is extremely high temperature. However, this is to increase the reliability of the engine startability at the present time, and if the cost is increased and the control accuracy is increased, the throttle valve closing control at start will be It is also possible to carry out regardless of the water temperature condition.

Thus, when the engine 1 is started, the water temperature TH
The throttle valve closing control execution flag FTHVC, which is set to "1" when W is in the range of A≤THW≤B, indicates that the engine 1
Is reset after a predetermined time has elapsed from the start. The reset time of the throttle valve closing control execution flag FTHVC can be set, for example, in consideration of the time when the air amount on the downstream side of the throttle valve when the throttle valve is closed disappears after the engine is started. This control will be described with reference to the flowchart shown in FIG. The routine shown in FIG. 3 is also executed in the initial routine only when the engine 1 is started, at predetermined time intervals, for example, every several ms.

In this control, first, at step 301, the engine speed Ne is read. The engine speed Ne is shown in Fig. 1.
It can be calculated from the crank position signal from the crank position sensor 21 shown in FIG. In the following step 302, the engine speed Ne read in step 301
Is greater than or equal to the set speed Nes, for example, 400 rpm or more. When the engine speed Ne is less than the set engine speed Nes, it is determined that the engine has not started yet, and the routine proceeds to step 303, where the value of the elapsed time counter after engine start CNT is cleared and this routine is ended.

On the other hand, in step 302, when the engine speed Ne is equal to or higher than the set speed Nes, it is determined that the engine is started, and the process proceeds to step 304, where the value of the post-start elapsed time counter CNT is incremented by 1 and the step is performed. Thirty
Go to 5. In step 305, it is determined whether or not the value of the elapsed time counter after start CNT has reached the reference count value C indicating a predetermined time. Then, the elapsed time counter CNT after starting
When the value of is not reaching the reference count value C, this routine is terminated as it is, and when the value of the elapsed time counter after start CNT reaches the reference count value C, the routine proceeds to step 306, where the throttle valve closing control execution flag FTHVC is executed. Is set to "0" and this routine is finished. In this way, the throttle valve closing control execution flag F, which was set to "1" at the time of starting the engine,
THVC is set to "0" when a predetermined time elapses after the engine is started.

FIG. 4 shows that when the engine 1 is cranked and started after the throttle valve 3 is fully closed when the engine 1 is started, the throttle valve 3 of the intake passage 2 in this embodiment is changed.
FIG. 6 is a characteristic diagram showing an air consumption rate R of the intake system when the air in the volume Vvol on the downstream side of V decreases with time. The intake system air consumption rate R in this embodiment is a value obtained by dividing the integrated consumption air amount ΣU consumed by the internal combustion engine 1 by the intake system air amount Vvol, and when the integrated consumption air amount ΣU is small, R is 0. Is a value close to, and cumulative air consumption ΣU
As R becomes larger, R gradually increases and approaches R. That is,
The air consumption rate R of the intake system in this embodiment is 0 ≦ R ≦
Since it is a value of 1, and is used like a coefficient thereafter, the intake system air consumption ratio R is called a transfer coefficient here.

When the engine 1 is started, the driver sets the ignition switch 17 to the starter position and
When the accelerator pedal is operated, in an internal combustion engine not equipped with an electronic throttle, the engine speed will increase according to the amount of depression of the accelerator pedal at the time of starting. On the other hand, in the internal combustion engine equipped with the electronically controlled throttle as in the present invention, it is possible to control the rotational speed at the time of starting the internal combustion engine regardless of the amount of depression of the accelerator pedal by the driver at the time of starting the engine 1.

As a result, in the present invention, when the engine 1 is cranked and started after the throttle valve 3 as shown in FIG. 4 is fully closed, the engine speed is controlled so that the transition coefficient R Can be obtained in advance by calculation and can be stored in the ROM 103 of the ECU 10. Actually, the characteristic that the air for the volume Vvol on the downstream side of the throttle valve 3 which is closed at the time of start-up decreases with time is a rotational speed of the engine 1 (a known value because it is controlled by the ECU 10 side). And the volumetric efficiency ηv used for calculating the air consumption amount obtained from the rotational speed map of the engine 1 (which indicates how much air is taken into the volume of the combustion chamber, and the engine speed is The larger the value, the smaller the value). That is,
The air amount (consumed air amount) U drawn into the combustion chamber for each revolution of the engine 1 after the engine is started can be obtained from the equation U = ηv × Vd × 1/2, and is obtained by integrating these. The transfer coefficient R can be obtained from the cumulative air consumption amount ΣU after the start of the start.

FIG. 5 is a flow chart showing an embodiment of a procedure for setting the opening degree of the electronically controlled throttle valve 3 when the engine 1 is started. The routine shown in FIG. 5 is executed every predetermined time, for example,
It is executed every few ms. In this embodiment, first, at step 501, the throttle valve closing control execution flag FTH
Read the value of VC. In the following step 502, it is determined whether or not the value of the throttle valve closing control execution flag FTHVC is "1".

When it is determined in step 502 that the value of the throttle valve closing control execution flag FTHVC is "0", it is determined that the engine 1 has been started and step 5
Go to 03. In step 503, the value of the time counter T is cleared and the process proceeds to step 504. In step 504, the normal ISC flow rate ISCN is calculated by a normal calculation formula. The normal calculation formula is the learning value of the ISC flow rate, the correction value by the water temperature, the correction value of the ISC flow rate at the time of starting, the correction value by turning on / off the air conditioner, the correction value by the presence or absence of an electric load, the power steering This is an equation for correcting with a correction value or the like by the operation. In the following step 505, the throttle valve opening θthv corresponding to the normal ISC flow rate ISCN calculated in step 504 is set as the throttle valve opening, and this routine is ended. The control when the start of the engine is completed is not the gist of the present invention, and a further description will be omitted.

On the other hand, if it is determined in step 502 that the value of the throttle valve closing control execution flag FTHVC is "1", it is determined that the engine 1 is being started and the routine proceeds to step 506. In step 506, the starter signal ST
Is 1 or not, that is, whether or not intake air is sucked into the combustion chamber of the engine 1 is determined. Then, when the intake air is not sucked into the combustion chamber, this routine is finished,
Step 5 when intake air is sucked into the combustion chamber
Proceed to 07.

In step 507, the value of the time counter T is incremented to calculate the integrated time during which the engine sucks intake air. In the next step 508, it is determined whether or not the cylinder discrimination of the engine after the engine 1 is cranked is completed. Then, when it is determined in step 508 that the cylinder determination is not completed, the process proceeds to step 509,
Throttle valve opening θ that allows the minimum ISC flow rate ISCmin
Set th1 as the throttle valve opening and end this routine.

On the other hand, if it is determined in step 508 that the cylinder determination is completed, the process proceeds to step 510. Step 5
In step 10, the transfer coefficient (intake air consumption rate) R corresponding to the value of the time counter T calculated in step 507 is set in the ECU.
Read from the ROM 103. In the following step 511, the normal ISC flow rate ISCN is calculated by the normal calculation formula as in the case of calculating in step 504, and this normal flow rate ISCN is multiplied by the transfer coefficient R calculated in step 510 to shift air amount ISCN. * Calculate R.

At step 512, the minimum ISC flow rate IS
Cmin and the transition air amount ISC calculated in step 511
Compare the magnitude with N * R. And ISCmin ≧ IS
In case of CN * R, the routine proceeds to step 509, where the throttle valve opening degree θth is the minimum ISC flow rate ISCmin.
Set 1 to end this routine. On the other hand, if ISCmin <ISCN * R at step 512, the routine proceeds to step 513, at which the throttle valve opening θth2 through which the transition air amount ISCN * R flows is set, and this routine ends.

As described with reference to FIG. 4, after the cranking of the engine 1 is started, the value of the transition coefficient R gradually increases and approaches 1 as the count value of the time of the time counter T increases. Therefore, the value of the throttle valve opening degree θth2 set in step 513 gradually increases, and finally becomes the normal ISC flow rate ISCH calculated in step 505.

FIG. 6 shows the starter signal, the throttle valve closing control execution flag FTHVC, the cylinder discrimination signal, the engine start counter CNT, the engine speed Ne in the above-mentioned embodiment.
5 is a time chart showing changes in ISC flow rate and throttle valve opening degree θth. When the value of the starter signal becomes 1 and the engine is started at time T0 when the throttle valve closing control execution flag FTHVC is "1", the value of the cylinder discrimination signal is 0 at this time, so the throttle The valve opening θth is set to the first opening θth1. After that, during the cranking until time T1, the throttle valve 3 remains at the fully closed opening θth1 and the minimum required ISC flow rate ISCmi.
n flows.

When cylinder discrimination is performed at time T1 during engine cranking, the minimum required ISC flow rate ISC
A comparison between min and the air amount ISCN * R during transition is made. And until time T2, ISCmin ≧ ISCN
Since * R, the throttle valve opening is set to the opening θth1 at which the minimum ISC flow rate ISCmin flows. On the other hand, when ISCmin <ISCN * R at time T2, the opening θ of the throttle valve opening through which the transition air amount ISCN * R flows
It is set to th2.

In this example, cranking continues for a predetermined time from time T0, the engine is started after time T1 and before time T2, and the engine speed Ne increases after the engine is started. When the engine speed Ne reaches the predetermined engine speed Nes at time T3 after time T2, the post-engine start counter CNT starts counting. Time T
After 2, the value of the throttle valve opening θth2 gradually increases as the value of the transfer coefficient R increases, as described in FIG.
Along with this, the ISC flow rate also increases, gradually increasing to normal ISC.
It approaches the flow rate ISCH.

In this embodiment, when the counter CNT after engine start reaches the predetermined value C and the throttle valve closing control execution flag FTHVC is set to "0" at time T4, the throttle valve is increased by increasing the value of the transition coefficient R. With the increase of the opening degree θth2, the ISC flow rate has also reached the vicinity of the normal ISC flow rate ISCH. In this way, the value of the counter CNT after engine start near the time when the ISC flow rate reaches the vicinity of the normal ISC flow rate ISCH due to the increase of the throttle valve opening θth2 is set to the predetermined value C
If selected, the throttle valve opening θth2 at the end of execution of the throttle valve closing control will be close to the throttle valve opening θthv calculated by the normal calculation formula, so when shifting from the throttle valve closing control to the valve opening control. It is possible to suppress the change in the intake air amount at.

As described above, in the present invention, as described in the embodiment, in the multi-cylinder internal combustion engine which controls the closing of the throttle valve at the time of starting the engine, the minimum I after the cylinder discrimination is performed.
By comparing the SC flow rate ISCmin and the air flow amount ISCN * R during transfer, and adjusting the throttle valve opening so that the larger ISC flow rate flows, the electronically controlled on-off valve closes to open. At the time of shifting to the control, it is possible to suppress an excessive change in the intake air amount, and it is possible to improve engine startability and prevent emission deterioration.

In the embodiment described above, the minimum I
The comparison between the SC flow rate ISCmin and the transition air amount ISCN * R is performed after cylinder discrimination. This comparison is made after the engine has been cranked for a predetermined number of times or after the engine has started cranking. It may be performed after a predetermined time has passed or the like. In the embodiment described above,
Although the description has been given of the case where the electronically controlled throttle valve 3 is used to close the intake passage of the internal combustion engine, instead of the electronically controlled throttle valve 3, an electronically controlled intake control valve is separately provided in the intake passage. The present invention can also be effectively applied.

[0040]

As described above, according to the intake control device for an internal combustion engine of the present invention, it is a multi-cylinder internal combustion engine in which an electronically controlled on-off valve is provided in the intake passage and is electronically controlled when the engine is started. In the case of controlling the closing of the on-off valve, it is possible to suppress an excessive change in the intake amount when shifting from the closing control of the electronically controlled on-off valve to the opening control, improving the engine startability and worsening the emission. There is an effect that the prevention of can be realized.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a configuration of an electronically controlled multi-cylinder internal combustion engine equipped with an intake control device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a flag setting procedure for executing throttle valve closing control.

FIG. 3 is a flowchart showing resetting of a flag for executing throttle valve closing control.

FIG. 4 is a characteristic diagram showing a change of an intake air consumption rate with respect to time.

FIG. 5 is a flow chart showing an embodiment of a procedure for setting the opening degree of the electronically controlled throttle valve at the time of starting of the present invention.

FIG. 6 is a time chart showing changes in a starter signal, a throttle valve closing control execution flag, a cylinder discrimination signal, an engine start counter, an engine speed, an ISC flow rate, and a throttle valve opening in the embodiment of the present invention.

[Explanation of symbols]

2 ... Intake passage 3 ... Throttle valve 4 ... Throttle motor 5 ... Throttle opening sensor 8 ... Fuel injection valve 10 ... ECU 17 ... Ignition switch 18 ... Atmospheric pressure sensor 19 ... Starter 20 ... Starter drive circuit 21 ... Crank position sensor 23 ... Ring gear 24 ... Timing rotor 25 ... Signal teeth 26 ... missing tooth

Continuation of front page (56) Reference JP-A-9-324677 (JP, A) JP-A-9-280061 (JP, A) JP-A-7-310636 (JP, A) JP-A-10-205381 (JP , A) JP-A-8-303272 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F02D 9/00-11/10 F02D 41/00-41/40

Claims (2)

(57) [Claims] 1. An intake control device for an internal combustion engine, which performs a valve closing control at the time of starting to close an intake passage by operating an electronically controlled opening / closing valve at the time of starting, wherein the electronically controlled opening / closing is performed when an ignition switch is turned on. First opening control means for controlling the opening of the valve to a first opening close to a fully closed state in which a slight gap is left between the intake passage and the intake passage; After the engine is cranked in the above condition, the intake air amount consumed by the internal combustion engine is calculated, and the intake air of each cylinder is introduced from the downstream side of the electronically controlled on-off valve. A transfer coefficient calculating means for calculating a transfer coefficient from an intake air amount in the volume of the intake passage up to the front of the valve and a consumption ratio of the intake air amount based on the value of the consumed air amount; Intake air amount required after the closing control is completed A transfer air amount calculating means for calculating a transfer air amount from the transfer coefficient, and a second opening and a first opening of the on-off valve for flowing the transfer air amount are compared. And a second opening degree control means for controlling the opening degree of the on-off valve to a larger opening degree, the intake air control apparatus for the internal combustion engine. 2. The intake control device for an internal combustion engine according to claim 1, wherein the second opening control means stops the operation when the elapsed time after the start of the engine exceeds a predetermined time. An intake control device for an internal combustion engine.