JPH09250404A - Intake controller for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve optimum EGR over a wide range of engine operating conditions by controlling EGR in a small quantity with high accuracy in a low load region and supplying the EGR in a large quantity in a high load region with ease at a low cost, and actuating an intake control valve and an additional opening/closing valve in coordination with each other. SOLUTION: A second (additional) EGR passage 54b bypassing an EGR valve 56 is provided independently of a first EGR passage 54a. An additional opening/ closing valve 80 is disposed in the second EGR passage 56b. Based on throttle opening degrees, engine operating conditions are classified into four steps: a low load region, an intermediate load region, a high load region and a fully opened run neighboarhood region. The operations of the additional opening/ closing valve 80 and a TCV 86 are coordinated with each other at each step, thereby achieving optimum EGR.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine intake control device for controlling intake air flowing into a cylinder, and more particularly to exhaust gas recirculation control means for recirculating a part of exhaust gas to an intake passage and tumble and swirl in the cylinder. The present invention relates to an intake control device for an engine including an intake control means for generating a gas flow such as

[0002]

2. Description of the Related Art Conventionally, an exhaust gas recirculation (hereinafter simply referred to as EGR) system for recirculating a part of exhaust gas in an exhaust passage to an intake passage and a part of an intake passage to tumble (longitudinal) 2. Description of the Related Art An intake control device for an engine including an intake control valve that produces a desired gas flow such as swirl flow) or swirl (lateral swirl flow) is known.

In a general EGR system, an E provided in the middle of an EGR passage that connects an exhaust passage and an intake passage.
The opening of the GR valve is controlled to adjust the amount of exhaust gas recirculated from the exhaust passage to the intake passage, thereby lowering the combustion temperature to reduce the NOx generation amount and reducing fuel consumption by reducing pumping loss. We are trying to improve. Here, as the EGR valve, there are a negative pressure type that uses a negative pressure in the intake pipe to displace the diaphragm, and an electronically controlled type that opens and closes the valve body using an electric motor.
Further, as the electronically controlled type, there are known ones that use a pulse motor such as a stepping motor to control the valve lift amount, and one that controls the power supply to the electromagnetic solenoid in a time proportional manner.

Since the EGR valve of the negative pressure type EGR valve is controlled in accordance with the throttle opening, its control range is naturally limited. Therefore, in recent years, a relatively large number of electronically controlled EGR valves have been proposed in order to realize an EGR rate most suitable for the operating state of the engine. In such a conventional EGR system, the pulse signal output to the stepping motor for driving the EGR valve is adjusted by a value set according to each operating state parameter such as the intake air amount of the engine, the number of revolutions, the intake pipe pressure, and the like. This makes it possible to optimize the EG
The lift amount of the EGR valve is controlled so as to realize the R ratio. Therefore, the optimum EG for each operating state of the engine
The R ratio is set in advance in a map, and when the operating condition of the engine changes, a pulse signal necessary for the stepping motor is output to realize the EGR ratio according to the changed operating condition. It

On the other hand, the intake control valve provided in the intake passage generates a gas flow such as tumble or swirl in the cylinder, which accelerates the flame propagation speed to improve the combustion state during low load running, thereby improving fuel economy. To achieve the improvement of Here, the intake control valve mainly includes a tumble control valve that generates a tumble along a substantially longitudinal section of the cylinder and a swirl control valve that generates a swirl along a substantially transverse section of the cylinder. The shape of the intake port is appropriately selected depending on whether the tumble or swirl is used.

Further, in the technique disclosed in Japanese Patent Laid-Open No. 5-99081, an electronically controlled EGR valve using a stepping motor is provided as a small flow rate control valve in the middle of the EGR passage, and in parallel with this electronically controlled EGR valve. Further, a negative pressure type EGR valve is provided as a large flow rate control valve. Then, by adjusting the opening degree of the electronic control type EGR valve based on the valve opening degree of the negative pressure type EGR valve, the EGR amount adjusted by the negative pressure type EGR valve and the EGR amount adjusted by the electronic control type EGR valve are adjusted. The opening degree of the electronically controlled EGR valve is controlled so that the total flow rate of the above is the optimum flow rate according to the operating conditions of the engine.

Further, Japanese Patent Laid-Open No. 59-49359 discloses a technique for permitting EGR only while the intake control valve for generating the swirl is closed, that is, while the swirl is being generated. Has been done.

Further, in the technique disclosed in Japanese Patent Laid-Open No. 5-113154, EGR is started before the swirl is stopped, whereby the torque increase due to the swirl stop and the EG.
Torque shock is reduced by offsetting the torque decrease due to the start of R.

[0009]

In the EGR device using the electronically controlled EGR valve as described above, the valve opening can be finely adjusted based on the engine operating conditions. Therefore, for example, it is possible to improve the EGR control accuracy under operating conditions such as a low load region where the required EGR amount is small. However, on the other hand, if the specifications of the EGR valve are determined in accordance with the control accuracy on the low load side, the required EGR amount may not be secured in the high load range.

That is, the EGR amount passing through the EGR valve is determined by the pressure (for example, the pressure difference between the exhaust side pressure and the intake side pressure) and the opening degree of the EGR valve, and therefore the large amount required in the high load range. To secure the EGR flow rate of
The opening area (throttle area) of the portion where the valve body of the EGR valve opens and closes must be sufficiently large. However, if the opening area is widened to match the high load side, a slight change in valve lift causes the opening area at that portion to change suddenly.
The EGR amount also changes rapidly.

Therefore, if the EGR valve set on the high load side is used to control the EGR amount in the low load region, it will be substantially close to a two-step control state of EGR ON or EGR OFF, which is a rough condition. The EGR control may cause a misfire or reduce drivability. That is, since the intake air amount is small in the low load region and the influence of the EGR on combustion is large, it is necessary to control the minute EGR with high accuracy. On the other hand, in the high load region, the intake air amount is large and a large amount of EGR is applied. However, since it has almost no effect on combustion, it is required to secure a large amount of EGR in order to obtain the effect of improving fuel efficiency by EGR in the high load range, and thus the two have a conflicting relationship. .

On the other hand, the tumble, the swirl, or the in-cylinder gas flow in which the tumble and the swirl are mixed by the intake control valve stabilizes the combustion state and enables the lean combustion operation and the like. Therefore, both the EGR control and the control of the intake control valve are involved in the combustibility, and the two have a close relationship. However, in the conventional technology, since both controls are controlled separately, it is not possible to realize the optimum EGR according to the engine operating state, and there is room for improvement in exhaust emission and fuel efficiency.

In order to solve such a drawback, in the technique disclosed in Japanese Patent Laid-Open No. 5-99081, a negative pressure type EGR valve for a high load range is provided in parallel with an electronically controlled EGR valve using a stepping motor. The large EGR flow rate in the high load range and the small EGR flow rate in the low load range are compatible with each other. However, providing a negative pressure type EGR valve in order to secure a large flow rate in the high load region leads to an increase in manufacturing cost. Moreover, in this conventional technique, EG
Since the R control and the control of the intake control valve are not associated with each other, the optimum EGR according to the engine operating state cannot be obtained.

Further, according to the technique disclosed in Japanese Patent Laid-Open No. 59-49359, the EGR is performed only while the swirl is generated.
By executing the above, the NOx generation amount is reduced. However, this conventional technique does not take into consideration the problem of achieving both high-precision EGR in the low load range and large-volume EGR in the high load range, and that EGR and swirl are achieved only in the low load range. It is not possible to obtain the optimum EGR in a wide engine operating condition because the operations are only partially related.

Further, in the technique disclosed in Japanese Unexamined Patent Publication No. 5-113154, EGR is started before the swirl is stopped to reduce the torque shock. However, even with this conventional technique, the above-mentioned Japanese Patent Laid-Open No. 59-49359.
High-precision EGR control and large-volume EGR, similar to the technique disclosed in the publication.
It is not taken into consideration that both and are compatible with each other, and
Since the EGR control and the control of the intake control valve are not coordinated according to the engine operating state, there is room for improving the combustibility.

The present invention has been made in view of the above-mentioned various problems, and an object thereof is to easily perform highly accurate exhaust gas recirculation in a low load region and large amount exhaust gas recirculation in a high load region. An object of the present invention is to provide an intake control device that is compatible with the structure and that is capable of simultaneously achieving optimum EGR control and combustibility improvement over a wide operating state.

[0017]

In order to achieve the above object, an intake control device according to the present invention is provided with an additional on-off operation opening / closing valve for communicating or blocking a new EGR passage provided separately from a normal EGR passage. By using this, both high precision control in the low load range and a large amount of EGR in the high load range are achieved, and the EGR control and the control of the intake control valve that generates gas flow are coordinated.

That is, an additional exhaust gas recirculation control means is provided separately from the normal exhaust gas recirculation control means, and the additional exhaust gas recirculation control means and the intake air control means are controlled in a coordinated manner based on a predetermined control pattern in accordance with engine operating conditions. This enables highly accurate EGR control in the low load range and a large amount of EGR in the high load range.
It is possible to achieve both of the above, and to realize the optimum EGR over a wide range of operating conditions.

Further, in each of four stages of a low load region, a medium load region, a high load region and a region near full-open running, an opening / closing operation of an additional opening / closing valve for opening / closing the additional exhaust gas recirculation passage and an opening / closing operation of the intake control valve are performed. It is possible to easily obtain the optimum EGR according to each operating condition by patterning and controlling.

Specifically, by forming the control pattern with the following four patterns, it is possible to obtain the optimum EGR according to the engine operating conditions. First, in the low load region, by closing both the additional opening / closing valve and the intake control valve, the combustion state is stabilized by the gas flow of the intake control valve, and a small amount of EGR is accurately supplied into the cylinder. Will be done.

Secondly, in the medium load range, by opening the additional opening / closing valve and closing the intake control valve, the combustion state is stabilized by the gas flow of the intake control valve, and a large amount of air is stored in the cylinder. EGR can be applied. Third
In addition, in the high load region, by opening both the additional opening / closing valve and the intake control valve, it is possible to reduce the intake resistance and supply a large amount of air, while applying a large amount of EGR. Fourth, in the vicinity of full-open running, by closing the additional opening / closing valve and opening the intake control valve, intake resistance is reduced and a large amount of air is supplied, while EGR is cut to reduce engine output. Can be increased.

Further, the EGR exhaust gas recirculation valve is composed of an electronic exhaust gas recirculation valve whose valve opening can be adjusted by an electric drive means, so that the EGR amount can be finely adjusted according to the engine operating conditions. Therefore, highly accurate EGR control in the low load region can be realized, and the operation of the present invention can be made more effective.

[0023]

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

First, FIG. 1 shows a basic overall configuration of an automobile engine device to which an intake control device according to an embodiment of the present invention is applied. An intake passage 12 and an exhaust passage 14 are provided in communication with the horizontally opposed engine body 10. An intake chamber 16 is opened upstream of the intake passage 12 toward the front of the vehicle body (not shown), and an intake pipe 22 branched from a surge tank 20 is connected to the downstream side of the intake passage 12 so as to correspond to each cylinder 18. The downstream ends of the intake pipes 22 communicate with the combustion chambers 26 via the intake ports 24. On the other hand, the downstream side of the exhaust passage 14 is connected to a muffler 28 attached to the rear part of the vehicle body.
An exhaust pipe 32 communicates with each combustion chamber 26 via each exhaust port 30 on the upstream side.

An air cleaner 3 for removing dust in the air is sequentially provided in the intake passage 12 from the upstream side thereof.
4. An air flow meter 36 for detecting the intake air amount Q and a throttle valve 38 for controlling the intake air amount according to the depression amount of an accelerator pedal (not shown) are provided.
The intake valve 12 bypasses the throttle valve 38.
An idle speed control (hereinafter, simply referred to as “ISC”) passage 40 provided in the vehicle is provided with an ISC valve 42 for adjusting the intake air amount during idling. The ISC valve 42 has a duty ratio of 40%. The opening and closing is adjusted by.

An injector 44 is provided downstream of each intake pipe 22 so as to face the intake port 24,
These injectors 44 atomize and inject the fuel pumped and supplied from the fuel pump 46 via the fuel pipe 48. Further, in the intake pipe 22, a tumble control valve (hereinafter, referred to as “intake control valve”, which will be described in detail in FIG.
"TCV") 86 is provided.

On the other hand, a catalyst 50 such as a three-way catalyst is provided near the engine body 10 side of the exhaust passage 14, and an upstream side of the catalyst 50 serves as an air-fuel ratio sensor for detecting the air-fuel ratio in the exhaust gas. O2 sensor 52 is provided.

The EGR passage 54 formed with a flow passage area having a diameter smaller than that of the intake pipe 22 and the exhaust pipe 32 is
The exhaust pipe 32 and the collecting portion of the intake pipe 22 are provided so as to communicate with each other, and an EGR valve 56 having a stepping motor as a drive source is attached in the middle of the EGR passage 54. The EGR passage 54 and the EGR valve 56
Will be described later in detail with reference to FIG.

Further, the combustion chamber 26 is provided in the cylinder head 58.
A spark plug 60 is provided facing the inside of the combustion chamber 26. The spark plug 60 is powered by a high voltage supplied through an igniter 62 and an ignition coil 64.
Forcibly ignite the air-fuel mixture inside at a predetermined ignition timing.

In the figure, 66 is a crank angle sensor for detecting the crank angle and engine speed N, and 68 is a crank angle sensor.
Is a knock sensor that detects knocking of the engine body 10, 70 is a water temperature sensor that detects the temperature of the cooling water, 72 is a cam angle sensor that detects the rotation angle of a cam provided on the cam shaft 74, and 76 is the throttle valve 38. Opening T
It is a throttle opening sensor as "engine operating state detecting means" for detecting h.

The engine control unit (hereinafter simply referred to as "ECU") 78 for inputting the detection signals from the above-mentioned drive control of each member and each sensor is an EGR.
Together with the valve 56, an additional opening / closing valve 80 to be described later, the TCV 86, etc., "exhaust gas recirculation control means", "additional exhaust gas recirculation control means", "intake control means" and "valve operation control means" are realized.

This ECU 78, as shown in FIG.
Input interface 7 for inputting signals from each sensor
8a, an output interface 78b for outputting a drive control signal to each member, a CPU 78c as a main arithmetic unit, an R for storing a control program and preset fixed data.
RA for storing detection signals from the OM 78d and each sensor
It is configured as a microcomputer system in which an M78e, a timer 78f and the like are connected to each other by a bus line 78g.

Further, as shown in FIG. 3, the ECU 78 realizes the following functions by utilizing the hardware resources such as the CPU 78c (FIG. 2). That is,
A load determination means 79a for determining whether or not the engine operating state is in a predetermined load range, and a valve operation control means 79b for cooperatively controlling the operations of the additional opening / closing valve 80 and the TCV 86 according to the determined load range. It is a control map 79c in which an optimal cooperative control pattern is mapped and stored for each operating condition, and the load determining means 79a and the control map 79c constitute "control pattern setting means".
The valve control means 79a may directly read the control map 79c based on the load determination by the load determination means 79b.

Next, the configuration of the intake control device according to the present embodiment will be described with reference to FIG.

EG illustrated as a single passage in FIG.
The R passage 54 is composed of a first EGR passage 54a and a second EGR passage 54b which is an additional EGR passage. More specifically, the second EGR passage 54b is provided so as to bypass the EGR valve 56 provided in the middle of the first EGR passage 54a, and the second EGR passage 54b is provided.
The inlet of the R passage 54b is connected on the upstream side of the EGR valve 56 in the middle of the first EGR passage 54a, and
The outlet of the passage 54b is connected to the collecting portion of the intake pipe 22 independently of the outlet of the first EGR passage 54a.
Although FIG. 3 shows an example in which the EGR passages 54a and 54b are formed separately, if the pipe walls are formed in common, the structure can be simplified and the mounting work can be reduced.

The EGR valve 56, as shown in FIG.
A valve body 56a, a return spring 56b for constantly urging the valve body 56a in the valve closing direction, and a return spring 56b.
Stepping motor 56c as "electric drive means" for displacing the valve body 56a in the valve opening direction against the spring force of the
It is comprised including. The EGR valve 56 variably controls the valve opening according to a control pulse signal from the ECU 78.

The EGR valve 56 has its valve body 5 so that a small amount of EGR in the low load range can be finely adjusted.
The shape of 6a, the valve lift amount per step, etc. are preset. The electric driving means is not limited to the stepping motor 56c, and other means such as a servo motor can be used.

An additional opening / closing valve 80 is provided in the middle of the second EGR passage 54b. The additional opening / closing valve 80 is configured as a butterfly valve, and is opened / closed by a negative pressure actuator 81 connected to its valve shaft. In FIG. 3, the diameter of the additional opening / closing valve 80 installation portion of the EGR passage 54b is shown for convenience of explanation.

The negative pressure actuator 81 has a control negative pressure chamber 81a connected to a three-way solenoid valve 82, and the solenoid valve 82 selectively introduces atmospheric pressure or suction negative pressure on the downstream side of the throttle valve 38. By doing so, the additional opening / closing valve 80 is opened or closed. By using a relatively high output electromagnetic actuator, the additional opening / closing valve 80 can be directly opened / closed by the electromagnetic actuator. Further, instead of the three-way solenoid valve 82, two two-way solenoid valves may be used and the atmospheric pressure and the suction negative pressure may be selectively supplied.

On the other hand, at the inflow side end (intake side of intake air) of the partition wall 84 which defines the inside of the intake port 24 into the main passage 24a located on the upper side in the figure and the auxiliary passage 24b located on the lower side in the figure. , TCV8 for opening and closing the sub passage 24b on the lower side in the drawing
6 is rotatably provided. The TCV 86 is opened / closed by a TCV actuator 88 composed of, for example, a negative pressure actuator, and when the valve is closed as shown by the solid line in the figure, the auxiliary passage 24b is closed to close the intake air to the upper main passage 2
A tumble is generated in the cylinder 18 by being guided to 4a. On the other hand, as indicated by the dotted line in the figure, TC
When V86 opens, the intake air flows into the main passage 24a and the sub passage 2
Since it flows into the cylinder 18 through both 4b, the suction resistance is reduced and the tumble is also eliminated.

Next, referring to FIG. 4, the control map 79c
The specific contents of will be explained. In this control map 79c, the horizontal axis represents the engine speed N and the vertical axis represents the throttle opening Th, and the preset throttle openings A, B, C, D are set.
It is determined whether the engine operating state is one of the four stages of the low load region, the medium load region, the high load region, and the fully open traveling vicinity region. That is, the throttle opening A is in the low load range, the throttle openings A to B are in the middle load range, the throttle openings B to C are in the high load range, and the throttle openings C to D are in the vicinity of full-open running. . And the control map 7
9c includes an additional opening / closing valve 80 for each of these operating states.
(Displayed as "FCV" in the figure) and the opening / closing operation of the TCV 86 are stored.

Next, the operation of the present embodiment will be described based on the flowchart of FIG.

First, the first step (hereinafter, simply "S")
In step 200, the throttle opening Th detected by the throttle opening sensor 76 is read, and in step S201, it is determined whether or not the read throttle opening Th is within the range corresponding to the low load range of "0 to A". To determine. When the throttle opening Th is within the range of "0 to A", it is determined as "YES" in S201 and S202.
Move on to

In step S202, the coordinated operation of each valve is read from the control map 79c shown in FIG.
Both the CV 86 and the additional opening / closing valve 80 are closed.
By closing the TCV 86, tumble is generated in the cylinder 18 to improve the combustibility, and by closing the additional opening / closing valve 80, the EGR amount is controlled by the EGR valve 56 only in a small amount with high accuracy according to the engine operating state. To be done.

On the other hand, when it is determined to be "NO" in S201, it is determined in S203 whether the throttle opening Th is within the range corresponding to the medium load range of "A to B". It If it is in the middle load range, S2
In 03, it is determined to be "YES" and the process proceeds to S204. In step S204, TC is set based on the control map 79c.
The V86 is closed and the additional opening / closing valve 80 is opened. Therefore, the combustibility is improved by the generation of tumble due to the closing of the TCV 86, and a large amount of EGR is introduced into the cylinder 18, which suppresses the rise of the combustion temperature.

If it is determined "NO" in S203, the process proceeds to S205, in which the throttle opening Th is "B".
It is determined whether or not it is within the range corresponding to the high load range "from C to C". And in the high load range, "YES"
Then, in S206, the TCV 86 and the additional opening / closing valve 8 are determined based on the control map 79c.
Both 0 are opened. The opening resistance of the TCV 86 reduces the intake resistance, and a large amount of intake air flows into the cylinder 18 to suppress the output reduction. Further, in the high load region, the intake air amount is large and even if a large amount of EGR is applied, there is almost no effect on combustion, so a large amount of EGR is introduced into the cylinder 18 by opening the additional opening / closing valve 80, and the combustion temperature rises. Is prevented.

On the other hand, when it is determined to be "NO" in S205, it means that the throttle opening Th is within the range corresponding to the fully open traveling vicinity from "C to D".
Move to S207. In this S207, the control map 79c
Based on the above, the TCV 86 is opened and the additional opening / closing valve 80 is closed. The intake resistance is reduced by opening the TCV 86, and the EGR is reliably cut off by closing the additional opening / closing valve 80. Where EGR
The valve 56 is closed in the vicinity of full-open running in order to adjust the valve opening according to the engine operating conditions according to a normal EGR control program (not shown). Therefore, by closing the additional opening / closing valve 80, the EGR is surely stopped, whereby a high engine output is drawn out.

As described above, the first EGR passage 5 whose flow passage area is controlled by the electronically controlled EGR valve 56.
Independently of 4a, a second EG which is an additional passage whose flow passage area is adjusted on / off by an additional opening / closing valve 80.
Since the basic configuration of providing the R passage 54b is provided, the EGR amount can be controlled with high accuracy by the EGR valve 56 in the low load region where the required EGR amount is small, while a large amount of EGR can be secured in the high load region.

Therefore, it is possible to easily realize both high precision control in the low load range and large amount of EGR in the high load range without a complicated structure, and in a wide range from the low load range to the high load range. Achieves optimum EGR and prevents deterioration of exhaust gas,
It is possible to improve fuel efficiency. That is, in the low load range,
Since EGR is performed only through the first EGR passage 54a, this small amount of EGR can be controlled with high accuracy by the valve opening degree of the EGR valve 56.

In the high load range, the second EGR passage 5
A large amount of EGR is obtained by adding the EGR channel area by 4b.
Can be secured. In the high load range, the flow path area can be controlled only by the first EGR passage 54a, which is approximately half the total EGR flow path area, so the control accuracy is lower than in the low load range, but in the high load range, the suction is originally performed. Large amount of air, large amount of E
There is almost no deterioration in combustion even after applying GR, so there is no problem in operating performance.

In particular, the additional opening / closing valve 80, which is a butterfly valve, is an on / off valve that simply opens or closes the second EGR passage 54b, and therefore is different from the prior art using a negative pressure type EGR valve. The overall structure can be simplified and the manufacturing cost can be reduced.

When the engine operating condition changes rapidly from the low load range to the high load range, or from the high load range to the low load range, the additional opening / closing valve 80 is opened and closed quickly. Optimal EG following sudden changes
R can be performed.

Further, since the additional opening / closing valve 80 and the TCV 86 are operated in cooperation with each other in accordance with the engine operating condition, the EGR most suitable for the engine operating condition can be realized and the engine operating condition can be widened. , NOx generation amount and fuel consumption can be reduced.

Further, the engine operating conditions are divided into four stages of a low load region, a medium load region, a high load region and a region near full-open running, and as shown in FIG. 4, the optimum valve operation is previously mapped for each stage. Since it is configured to be controlled, the optimum EGR can be realized for each operating condition. Particularly, in the low load region, both the additional opening / closing valve 80 and the TCV 86 are closed, so that a small amount of EGR can be accurately supplied into the cylinder 18 in which the combustion state is stabilized by the tumble, and the combustion stability is impaired. It is possible to improve the amount of NOx generated and the fuel consumption.

Further, in the medium load range, since the TCV 86 is closed and the additional opening / closing valve 80 is opened, a large amount of EGR is supplied into the cylinder 18 whose combustion state has been stabilized by tumble to raise the combustion temperature. Can be suppressed. Further, in the high load region, both the TCV 86 and the additional opening / closing valve 80 are opened, so that the suction resistance can be reduced and a large amount of air can be supplied while preventing the combustion temperature from rising. Further, in the vicinity of the fully open traveling, the TCV 86 is opened and the additional opening / closing valve 80 is closed. Therefore, it is possible to cut the EGR while reducing the intake resistance and obtain a high engine output.

The present invention is not limited to the configurations described in the above embodiments, and various modifications can be made within the scope of the present invention. For example, in the above-described embodiment, the case where the invention is applied to the horizontally opposed engine is illustrated, but the invention is not limited to this, and the invention can be applied to other types of engines such as a V-type engine and an in-line engine. Also,
In the above embodiment, the case where the engine operating condition is determined by the throttle opening Th is illustrated, but the present invention is not limited to this, and other engine operating conditions such as the fuel injection amount, the engine speed, and the suction negative pressure are reflected. Parameters may be used.

Further, in the above embodiment, the TCV 86 for generating tumble was illustrated as an example of the intake control valve.
Not limited to this, other types of intake control valves such as swirl control valves that generate swirl may be used.

[0058]

As described above, according to the engine intake control device of the present invention, the additional opening / closing valve is closed under the operating condition that the intake control means and the additional exhaust gas recirculation control means cooperate with each other. As a result, highly accurate EGR can be performed by the exhaust gas recirculation valve, while a large amount of EGR can be easily secured by opening the additional opening / closing valve. As a result, it is possible to control the opening and closing of the intake control valve while achieving optimum EGR over a wide range of engine operating conditions in combination with the opening and closing operation of the intake control valve, improving combustibility, reducing NOX emissions, and improving fuel efficiency. Etc. can be achieved.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an overall configuration of an engine device to which an embodiment of the present invention is applied.

FIG. 2 is a configuration explanatory view showing an internal configuration of an ECU in FIG.

FIG. 3 is a configuration explanatory view of an intake air control device according to the embodiment.

FIG. 4 is an explanatory diagram showing specific contents of a control map.

FIG. 5 is a flowchart showing an intake control method according to an embodiment.

[Explanation of symbols]

 10 engine body 12 intake passage 54 EGR passage 54a first EGR passage 54b second EGR passage 56 EGR valve 80 additional opening / closing valve 76 throttle sensor (operating state detection means) 78 ECU (exhaust gas recirculation control means, intake control means) 79a Load determination means (control pattern setting means) 79b Valve operation control means 79c Control map (control pattern setting means)

Claims (5)

[Claims] 1. An intake control apparatus for an engine, comprising: an exhaust gas recirculation control means for recirculating exhaust gas in an exhaust passage to an intake passage according to an engine operating state; and an intake control means for generating a predetermined gas flow in a cylinder. In addition, in addition to the exhaust gas recirculation control device, an additional exhaust gas recirculation control device that recirculates exhaust gas in the exhaust gas passage to the intake air passage, and a predetermined control of the additional exhaust gas recirculation control device and the intake air control device according to engine operating conditions. An intake control device for an engine, comprising: a valve operation control means for controlling in a coordinated manner based on a pattern. 2. Exhaust gas recirculation control means for controlling the valve opening degree of an exhaust gas recirculation valve provided in the middle of an exhaust gas recirculation passage that connects the intake passage and the exhaust passage, and opening / closing of the intake control valve. An intake air control device for an engine, comprising: an intake air control means for generating a predetermined gas flow in a cylinder by controlling an operation; and an additional exhaust gas recirculation that bypasses the exhaust gas recirculation valve and connects the intake air passage and the exhaust gas passage. An additional exhaust gas recirculation control means having a passage and an additional opening / closing valve for opening and closing the additional exhaust gas recirculation passage, an operating state detecting means for detecting an engine operating state, and a predetermined control pattern according to the detected engine operating state. Control pattern setting means for setting, and opening / closing operation of the additional opening / closing valve and opening / closing of the intake control valve based on the set control pattern. Intake control device for an engine is characterized by providing a valve operation control means for controlling by coordinating work. 3. The control pattern includes an opening / closing operation of the additional opening / closing valve and an opening / closing operation of the intake control valve for each of four stages of a low load region, a medium load region, a high load region and a region near full-open running. The intake control device for an engine according to claim 1, wherein the intake control device is patterned. 4. The control pattern is configured such that both the additional opening / closing valve and the intake control valve are closed in a low load range,
In the medium load range, the additional opening / closing valve is opened while the intake control valve is closed, in the high load range both the additional opening / closing valve and the intake control valve are opened, and in the vicinity of full open travel, the additional opening / closing valve is opened. 4. The engine intake control device according to claim 3, further comprising an operation pattern of closing the intake valve while opening the intake control valve. 5. The intake control according to claim 1, wherein the exhaust gas recirculation valve is an electronic exhaust gas recirculation valve whose valve opening can be adjusted by an electric drive means. apparatus.