JP2010090869A - Controller for internal combustion engine - Google Patents

Abstract

In an internal combustion engine having a blow-by gas reduction device capable of adjusting a blow-by gas flow rate continuously or stepwise by a PCV valve, deterioration of combustibility of the internal combustion engine is prevented when the intake pressure changes.
When it is detected that the internal combustion engine operation is in a transient state based on an estimated intake pressure change amount dlmv (YES in S110), a target PCV flow rate qpcv corrected with a target PCV flow rate reduction correction amount cqpcv. Is set (S114, S116), and the opening of the PCV valve is reduced. For this reason, even if an increase in the blowby gas flow rate occurs due to a decrease in the intake pressure at the position of the blowby gas discharge port during the transient state of the internal combustion engine operation, the increase is prevented by reducing the opening of the PCV valve. This can prevent deterioration of the combustibility of the internal combustion engine when the intake pressure changes, and prevent deterioration of drivability and exhaust components in the vehicle.
[Selection] Figure 2

Description

  The present invention relates to a control device for an internal combustion engine including a blow-by gas reduction device that discharges blow-by gas to an intake system by adjusting a blow-by gas flow rate continuously or stepwise by a blow-by gas adjusting valve.

  2. Description of the Related Art In an internal combustion engine, a blow-by gas reduction device that discharges blow-by gas to an intake system in order to prevent stagnation of blow-by gas in a crankcase or a head cover is known (see, for example, Patent Documents 1 and 2).

  In Patent Document 1, in order to determine an appropriate amount of blow-by gas, the blow-by gas flow rate is adjusted by a blow-by gas adjustment valve in accordance with the amount of fuel contained in the blow-by gas. Specifically, the opening degree of the blow-by gas adjusting valve is adjusted according to the fuel injection timing and the air-fuel ratio.

In Patent Document 2, in order to prevent the introduction of blow-by gas from affecting the combustibility of the internal combustion engine when the lubricating oil is greatly diluted with fuel, the air-fuel ratio is reduced when the fuel injection time is minimized. The opening degree of the blow-by gas adjusting valve is adjusted so as to be in an appropriate state.
Japanese Patent Laid-Open No. 10-77821 (page 3-4, FIGS. 1-4) JP 2006-52664 A (page 6-7, FIG. 2)

  However, in Patent Documents 1 and 2, since the opening of the blow-by gas adjusting valve is adjusted according to the fuel injection timing and the air-fuel ratio, it does not correspond to the change in the flow rate of the blow-by gas to the intake system. It cannot be used when the intake pressure fluctuates during a transition.

  In particular, it cannot cope with a transient situation where the intake pressure decreases and the blow-by gas flow rate increases, and the air-fuel ratio decreases excessively, which deteriorates the combustibility of the internal combustion engine and decreases drivability and exhaust components. There is a risk of inviting.

  An object of the present invention is to prevent deterioration of combustibility of an internal combustion engine when the intake pressure changes in an internal combustion engine equipped with the above-described blowby gas reduction device.

In the following, means for achieving the above object and its effects are described.
The internal combustion engine control device according to claim 1 is a control for an internal combustion engine having a blow-by gas reduction device that releases blow-by gas to an intake system by adjusting a flow rate of blow-by gas continuously or stepwise by a blow-by gas adjusting valve. An internal combustion engine transient state detection means for detecting a transient state of the internal combustion engine operation, and the blowby gas when the internal combustion engine operation is detected to be in a transient state by the internal combustion engine transient state detection means It is characterized by comprising a valve throttle means at the time of transition for reducing the opening of the adjusting valve.

  The transient valve restricting means reduces the opening of the blow-by gas adjusting valve when the internal combustion engine operation is detected to be in a transient state by the internal combustion engine transient state detecting means. For this reason, when the internal combustion engine operation becomes a transient state, even if a situation occurs in which the flow rate of the blowby gas increases due to a decrease in the intake pressure, The increase is prevented. This can prevent deterioration of the combustibility of the internal combustion engine when the intake pressure changes.

The internal combustion engine control apparatus according to claim 2 is the internal combustion engine control apparatus according to claim 1, characterized in that the control apparatus is an internal combustion engine that injects fuel into a cylinder.
In particular, in an internal combustion engine that injects fuel into a cylinder, the fuel dilution ratio of the lubricating oil tends to increase, so the fuel concentration in the blowby gas tends to increase, and fluctuations in the flow rate of the blowby gas are particularly large, affecting the combustibility. To do. For this reason, in such an internal combustion engine that injects fuel into the cylinder, an increase in blow-by gas flow rate is prevented in a transient state of the internal combustion engine operation, and the effect of preventing deterioration of combustibility becomes remarkable.

  An internal combustion engine control apparatus according to claim 3 is an internal combustion engine control apparatus according to claim 1 or 2, wherein the internal combustion engine control apparatus adjusts the amount of intake air taken into the cylinder by adjusting the maximum valve lift amount of the intake valve. It is a control device.

  Even in an internal combustion engine of this type that adjusts the intake air amount by adjusting the maximum valve lift amount of the intake valve, if the maximum valve lift amount of the intake valve is rapidly reduced, such as during sudden deceleration, the intake stroke There is a case where the intake pressure on the intake port side is greatly reduced in a pulse manner. This increases the fluctuation of the blow-by gas flow rate, which may affect the combustibility. Even when the intake pressure changes in an internal combustion engine of the type that adjusts the maximum valve lift amount of the intake valve, the opening degree of the blow-by gas adjusting valve is reduced in a transient state of the internal combustion engine operation. As a result, the deterioration of the combustibility of the internal combustion engine can be prevented.

  The internal combustion engine control device according to claim 4, wherein the internal combustion engine transient state detection means detects a blow-by gas as a transient state of the internal combustion engine operation. It is characterized in that the amount of change in the intake pressure in the portion that releases the air is detected.

  The internal combustion engine operation transient state can detect the amount of change in intake pressure at the portion where blow-by gas is released as the transient state of the internal combustion engine operation, and if the transient state of the internal combustion engine operation is found based on this change amount, The valve throttle means reduces the opening of the blow-by gas adjusting valve. This prevents an increase in blow-by gas flow rate. In this way, it is possible to prevent deterioration of the combustibility of the internal combustion engine when the intake pressure changes.

  6. The internal combustion engine control apparatus according to claim 5, wherein the internal combustion engine transient state detection means is an internal combustion engine as a transient state of the internal combustion engine operation. The amount of change in the flow rate of blowby gas accompanying the change in the operating state is detected.

  The transient state of the internal combustion engine operation can detect the change amount of the blow-by gas flow accompanying the change of the operation state of the internal combustion engine as the transient state of the internal combustion engine operation, and if the transient state of the internal combustion engine operation is found based on the change amount The transient valve restricting means reduces the opening of the blow-by gas adjusting valve. This prevents an increase in blow-by gas flow rate. In this way, it is possible to prevent deterioration of the combustibility of the internal combustion engine when the intake pressure changes.

  The internal combustion engine control apparatus according to claim 6, wherein the internal combustion engine transient state detection means is configured such that the amount of change corresponds to a transient state of the internal combustion engine operation. When it is within the change amount region, it is detected that the internal combustion engine operation is in a transient state.

  More specifically, the internal combustion engine transient state detection means provides a reference change amount region corresponding to the internal combustion engine operation transient state, and if it is outside the reference change amount region, it is not in the transient state but in the reference change amount region. If so, it can be detected that the engine is in an operation transient state.

  As a result, the transient state of the internal combustion engine operation can be easily determined, and the amount of change in the steady state can be avoided, so that deterioration of the combustibility of the internal combustion engine can be prevented at an appropriate timing. Therefore, combustion stability can be maintained while sufficiently treating the blow-by gas.

  The internal combustion engine control apparatus according to claim 7, wherein the transient valve throttle means is an internal combustion engine by the internal combustion engine transient state detection means. When it is detected that the operation is in a transient state, the opening degree of the blow-by gas adjusting valve is reduced according to the degree of the transient state of the internal combustion engine operation.

  The opening degree of the blow-by gas adjusting valve in the transient state of the internal combustion engine operation may be reduced according to the degree of the transient state. As a result, when the intake pressure changes, the blow-by gas flow rate can be adjusted more appropriately, and more stable combustibility can be maintained.

  The internal combustion engine control device according to claim 8, wherein the transient valve throttle means is an internal combustion engine by the internal combustion engine transient state detection means. When it is detected that the operation is in a transient state, and the transient state of the internal combustion engine operation is a state that promotes an increase in the flow rate of blow-by gas, the opening degree of the blow-by gas adjusting valve is reduced. Features.

  On the side where the transient state of the internal combustion engine operation promotes the reduction of the blow-by gas flow rate, the blow-by gas is less likely to cause combustibility problems. It is good also as reducing the opening degree of a valve | bulb. As a result, the frequency of changing the opening degree of the blow-by gas adjusting valve can be reduced, and the durability of the blow-by gas adjusting valve can be maintained high.

  The internal combustion engine control device according to claim 9, wherein the blow-by gas reduction device includes an internal combustion engine speed, an internal combustion engine load, and a lubricating oil. The target value of the opening degree of the blow-by gas adjusting valve or the target value of the target blow-by gas flow rate based on the opening degree of the blow-by gas adjusting valve is set based on the diluted state by the fuel, and becomes this target value As described above, the blow-by gas adjusting means for adjusting the opening degree of the blow-by gas adjusting valve is provided.

  More specifically, the blow-by gas reduction device provided with the blow-by gas adjusting means as mentioned above can be mentioned. In such precise blow-by gas flow control, it is possible to maintain an appropriate blow-by gas flow rate, and to prevent deterioration in combustibility of the internal combustion engine when the intake pressure changes.

  The internal combustion engine control apparatus according to claim 10, wherein the transient valve throttle means is a transient of the internal combustion engine operation detected by the internal combustion engine transient state detection means. A reduction correction amount is set according to the state, and the target value in the blow-by gas adjusting means is reduced and corrected by the reduction correction amount.

  As described above, the transient valve throttle means can reduce the opening of the blow-by gas adjusting valve during the transient operation of the internal combustion engine by correcting the target value by the reduction correction amount.

[Embodiment 1]
FIG. 1 is a block diagram showing a schematic configuration of an internal combustion engine control apparatus to which the above-described invention is applied. The internal combustion engine 2 is a gasoline engine and is mounted on the vehicle for driving the vehicle. An intake passage 4 for supplying air to the combustion chamber is provided in the intake system of the internal combustion engine 2, and an intake flow rate sensor 6 for detecting the intake flow rate GA (g / s) is arranged in the middle of the intake passage 4. An air cleaner 8 is disposed upstream of the intake flow sensor 6.

  A breather hose 10, which is an intake pipe of a blow-by gas reduction device (hereinafter referred to as “PCV”), is connected downstream of the intake flow sensor 6, and intake air is introduced into the internal space of the crankcase and the head cover of the internal combustion engine 2. It has been introduced.

  An intake manifold 12 that also serves as a surge tank is provided downstream of the position where the breather hose 10 is connected, and the intake air is distributed to the intake ports of each cylinder (here, four cylinders) via each branch passage 12a. .

  The intake valve provided in each cylinder of the internal combustion engine 2 is capable of adjusting the maximum valve lift amount continuously or stepwise by the variable valve device 14. The state of adjustment of the maximum valve lift amount by the variable valve device 14 is detected by a valve lift amount sensor 14a.

  Therefore, the intake air distributed to each cylinder by each branch passage 12a is adjusted in accordance with the maximum valve lift amount of the intake valve adjusted by the variable valve operating device 14.

  During the intake air sucked into the cylinder, the fuel is directly injected by the fuel injection valve provided in each cylinder, whereby an air-fuel mixture is formed in the cylinder. The air-fuel mixture is burned by being ignited by a spark plug in the combustion stroke. Thereafter, it is discharged from the exhaust valve in the exhaust stroke.

  A PCV discharge path 16 is connected to each branch path 12a of the intake manifold 12, and blow-by gas returning from the internal space of the crankcase and the head cover of the internal combustion engine 2 is sucked into the intake air from the discharge ports 16a. Released. The discharge port 16a may be provided not at the branch passage 12a of the intake manifold 12 but at the intake port of each cylinder.

  A PCV valve 18 (corresponding to a blow-by gas adjusting valve) is provided in the middle of the PCV discharge path 16, and the opening degree PCVa of the PCV valve 18 is not controlled by on / off control but by an electric motor or a duty solenoid. It is adjusted continuously or stepwise according to the operating state of the internal combustion engine 2.

The output of the internal combustion engine 2 is output to the speed reduction mechanism and the differential device side via the transmission 20, and is transmitted to the drive wheel side of the vehicle.
In addition to the intake flow sensor 6 and the valve lift amount sensor 14a described above, the internal combustion engine 2 and the vehicle are provided with various sensors that detect the running state and the engine operating state. Here, the accelerator pedal 22 as a request instruction device operated by the vehicle driver is provided with an accelerator sensor 24 for detecting an accelerator operation amount ACCP (%) which is an operation amount thereof. Further, the crankshaft of the internal combustion engine 2 is provided with an internal combustion engine speed sensor 26 for detecting the engine speed NE (rpm), and a vehicle speed sensor 28 for detecting the vehicle speed SPD from the rotational speed of the output shaft of the transmission 20 and the drive wheels. It has been.

  The electronic control unit (hereinafter abbreviated as “ECU”) 30 performs PCV valve opening control, intake valve valve lift control, ignition timing control based on these various detection data and data stored in the internal memory. , Variable valve timing (VVT) control and other controls are executed.

  The ECU 30 inputs signals between the CPU that executes arithmetic processing related to various controls, the ROM that stores programs and data necessary for the control, the RAM that temporarily stores the arithmetic results of the CPU, and the outside. -It is configured with input / output ports for output.

  In the present embodiment, the target output torque Tp of the internal combustion engine 2 is calculated based on the operation amount of the accelerator pedal 22 by the vehicle driver, and the intake is performed at the maximum valve lift amount of the intake valve based on the target output torque Tp. A so-called torque demand control is performed in which the output torque of the internal combustion engine 2 is controlled by adjusting the amount of air. Instead of torque demand control, control that adjusts the maximum valve lift amount of the intake valve based on the accelerator operation amount ACCP may be used.

  FIG. 2 shows processing for setting a target PCV flow rate (target value of blow-by gas flow rate) used for PCV valve opening control executed by the ECU 42. This target PCV flow rate setting process is a process that is repeatedly executed in a time cycle.

  When this processing is started, first, a pre-correction target PCV flow rate qpcv0 is calculated based on the current internal combustion engine speed NE, the internal combustion engine load, and the estimated fuel dilution rate (S102). Here, the pre-correction target PCV flow rate qpcv0 is a target value determined according to the operating state of the internal combustion engine 2 (the internal combustion engine speed NE, the internal combustion engine load, and the estimated fuel dilution rate). This is the target value of the flow rate (g / s) of the blow-by gas discharged from the outlet 16a into each branch passage 12a of the intake manifold 12 or the intake port. An internal combustion engine load factor KL is used as the internal combustion engine load. The internal combustion engine load factor KL is a ratio (%) of the actual intake air amount to the reference maximum intake air amount per rotation of the internal combustion engine 2, and is calculated from the intake flow rate GA and the internal combustion engine speed NE.

  The estimated fuel dilution rate is obtained, for example, from a map or the like based on the operating state of the internal combustion engine 2 and the fuel mixed in the lubricating oil and the volatilized fuel, and the amount of fuel accumulated in the lubricating oil is calculated from the difference therebetween. Ask. Or it calculates | requires based on the gap | deviation in the air fuel ratio control by the air fuel ratio sensor provided in the exhaust pipe.

  Next, the required torque is calculated from the accelerator operation amount ACCP (S104). Actually, the relationship between the accelerator operation amount ACCP and the output torque required for the internal combustion engine 2 is designed in advance, and a map of the accelerator operation amount ACCP and the output torque is created based on this relationship, Calculate the required torque from the map. This map may be set for each internal combustion engine speed NE, and the required torque may be calculated from the accelerator operation amount ACCP and the internal combustion engine speed NE. Further, the required torque may be calculated in consideration of the vehicle speed SPD.

  Next, the target internal combustion engine speed NEt, the target intake valve opening timing VVTt, the target intake cam operating angle θt, and the target intake valve maximum valve lift amount LFTt are calculated from the required torque (S106).

  Next, each target value is determined from the relationship between the current internal combustion engine speed NE, the intake valve opening timing VVT, the intake cam operating angle θ, the intake valve maximum valve lift amount LFT, and the target values NEt, VVTt, θt, and LFTt. An estimated intake pressure change amount dlmv, which is an intake pressure change occurring at the position of the discharge port 16a immediately after control by NEt, VVTt, θt, and LFTt, is calculated (S108). This calculation is, for example, calculated from a map obtained in advance by actual measurement or theoretical calculation based on the difference between each current value NE, VVT, θ, LFT and each target value NEt, VVTt, θt, LFTt.

  Next, in order to determine whether or not the estimated intake pressure change amount dlmv calculated in this way destabilizes the combustibility of the internal combustion engine 2, it is determined whether or not it exceeds the reference value DLMV1. (S110). The reference value DLMV1 is set as a value for determining whether or not the internal combustion engine operation transient state is a state that promotes an increase in blow-by gas flow rate. (A) of the timing chart shown in FIG. 3 shows the relationship between the estimated intake pressure change amount dlmv and the reference value DLMV1. A region exceeding the reference value DLMV1 corresponds to a reference change amount region.

  If dlmv ≦ DLMV1 (NO in S110), a target PCV flow rate reduction correction amount cqpcv (corresponding to a reduction correction amount) to be described later is cleared to zero (S112), and a process for obtaining the target PCV flow rate qpcv using Equation 1 Performed (S116).

[Formula 1] qpcv <-qpcv0-cqpcv
Here, the pre-correction target PCV flow rate qpcv0 is the value calculated in step S102. Therefore, in Equation 1, the target PCV flow rate qpcv0 before correction is corrected with the target PCV flow rate reduction correction amount cqpcv to obtain the target PCV flow rate qpcv as the corrected target PCV flow rate. However, when it is determined NO in step S110 as in this time, the target PCV flow rate reduction correction amount cqpcv is cleared to zero (cqpcv ← 0) in the immediately preceding step S112. For this reason, in this step S116, the target PCV flow rate qpcv0 before correction is set as it is as the value of the target PCV flow rate qpcv. Therefore, no correction is actually made.

  In this way, this processing is temporarily exited. Again, at the execution timing of the target PCV flow rate setting process (FIG. 2), the process from step S102 is started. As long as dlmv ≦ DLMV1 (NO in S110), that is, as long as it is outside the reference change amount region. The above-described processing is repeated. In FIG. 3, the timings before the timing t0 and after the timing t1 correspond.

  When the driver depresses the accelerator pedal 32 or the like and the internal combustion engine operation becomes a transient state, an intake pressure change occurs at the position of the discharge port 16a of the discharge path 16, and dlmv> DLMV1 (YES in S110). ), Within the reference change amount region. Therefore, the target PCV flow rate reduction correction amount cqpcv is then calculated based on the estimated intake pressure change amount dlmv representing the transient state of the internal combustion engine operation (S114). In FIG. 3, timings t0 to t1 correspond.

  In this step S114, the difference is obtained by subtracting the reference value DLMV1 from the estimated intake pressure change amount dlmv, and the target PCV flow rate reduction correction amount cqpcv (> 0) is calculated from this difference by a map or theoretical calculation Fcpcv. . As a result, as shown in FIG. 3B, the target PCV flow rate reduction correction amount cqpcv> 0 at timings t0 to t1.

  Then, as shown in the equation 1, the target PCV flow rate qpcv0 before correction is corrected by the target PCV flow rate reduction correction amount cqpcv to obtain the target PCV flow rate qpcv (S116). Since the target PCV flow rate reduction correction amount cqpcv> 0 this time, correction is actually performed.

  Thereafter, as long as dlmv> DLMV1 (YES in S110: t0 to t1), the processes in steps S114 and S116 continue, and as shown by the solid line in FIG. The fuel ratio A / F is prevented from being destabilized due to a change in the intake pressure when the internal combustion engine operation state transitions. That is, the air-fuel ratio is temporarily prevented from being excessively rich due to an increase in the blow-by gas flow rate when the intake pressure changes, thereby preventing the combustibility of the internal combustion engine 2 from deteriorating.

If the processes shown in steps S114 and S116 are not performed, the combustion stability is hindered by temporarily being excessively enriched as indicated by a broken line in FIG.
In the configuration described above, the relationship with the claims corresponds to the ECU 42 as the internal combustion engine transient state detection means, the transient valve throttle means, and the blow-by gas adjustment means. Steps S102 to S110 of the target PCV flow rate setting process (FIG. 2) correspond to the process as the internal combustion engine transient state detection means, and steps S114 and S116 correspond to the process as the transient valve throttle means. The process for calculating the target PCV flow rate qpcv0 before correction in step S102 and the target PCV flow rate setting process (FIG. 2) are executed separately, and the opening degree PCVa of the PCV valve 18 is adjusted based on the target PCV flow rate qpcv. The process to perform corresponds to the process as blow-by gas adjusting means.

According to the first embodiment described above, the following effects can be obtained.
(I). In the target PCV flow rate setting process (FIG. 2), when it is detected that the internal combustion engine operation is in a transient state based on the calculated estimated intake pressure change amount dlmv (YES in S110), the target PCV flow rate reduction correction amount The target PCV flow rate qpcv corrected by cqpcv is set (S114, S116), and the opening degree of the PCV valve 18 is reduced. For this reason, when the operation of the internal combustion engine becomes a transitional state, the intake pressure change at the position of the discharge port 16a of the discharge path 16, especially the intake pressure is lowered, and the blow-by gas flow rate is likely to increase. However, the increase in the opening degree of the PCV valve 18 is prevented. This can prevent deterioration of the combustibility of the internal combustion engine 2 when the intake pressure changes. And since combustibility can be maintained satisfactorily in this way, it is possible to prevent a decrease in drivability and deterioration of exhaust components in the vehicle.

  (B). In particular, a reference change amount region (dlmv> DLMV1) is defined by the reference value DLMV1, and the opening of the PCV valve 18 is reduced within the reference change amount region, assuming that the internal combustion engine operation is in a transient state. For this reason, it is possible to easily determine the transient state of the internal combustion engine operation and not to consider the change amount (dlmv ≦ DLMV1) in the steady state, so that it is possible to prevent deterioration of the combustibility of the internal combustion engine 2 at an appropriate timing. it can. Therefore, combustion stability can be maintained while sufficiently treating the blowby gas.

  (C). The calculation of the target PCV flow rate qpcv (S114, S116) by correcting the target PCV flow rate qpcv0 before correction is the difference between the estimated intake pressure change amount dlmv and the reference value DLMV1, that is, the change amount of the intake pressure. The target PCV flow rate qpcv is calculated with correction so that the target PCV flow rate qpcv0 before correction is reduced according to the degree of the transient state. For this reason, the blow-by gas flow rate can be adjusted more appropriately, and more stable combustibility can be maintained.

  (D). The problem of combustion instability due to blow-by gas hardly occurs on the side where the flow rate of the blow-by gas is reduced by the transient state of the internal combustion engine operation changing the intake pressure at the position of the discharge port 16a of the discharge path 16. Therefore, as in the present embodiment, the target PCV flow rate correction (S114, S116) is performed only when the transient state of the internal combustion engine operation promotes the increase of the blowby gas flow rate (YES in S110). As a result, the frequency of changing the opening degree of the PCV valve 18 can be reduced, and the durability of the PCV valve 18 can be maintained high.

  (E). In particular, since the internal combustion engine 2 is a type that injects fuel into the cylinder, a large amount of fuel was injected into the cylinder until just before the transient when the operating state of the internal combustion engine changes from high load to low load. The fuel dilution rate of oil is high. And since it is a high temperature state, the fuel vapor concentration in blow-by gas is also high. For this reason, the air-fuel ratio becomes rich due to the increase in the flow rate of blow-by gas, and combustion instability is likely to occur. However, in this embodiment, since the PCV valve 18 is throttled in such a case (S114, S116), the prevention of instability of combustibility becomes significant.

[Embodiment 2]
FIG. 4 is a block diagram showing a schematic configuration of the internal combustion engine control device of the present embodiment. The internal combustion engine 102 does not adjust the intake air amount by adjusting the maximum valve lift amount of the intake valve. Instead of adjusting the maximum valve lift amount, the opening degree of the throttle valve 114 is adjusted by the actuator 114a, so that it is supplied to each cylinder of the internal combustion engine 102 via the surge tank portion 112a and the branch passage 112b of the intake manifold 112. The intake air volume is adjusted. The opening of the throttle valve 114 (throttle opening TA) is detected by a throttle opening sensor 114b.

  Further, the breather hose 110 of the PCV introduces intake air into the internal space of the crankcase and the head cover from the position between the intake flow sensor 106 and the throttle valve 114, and the discharge path 116 is the position of the surge tank portion 112a of the intake manifold 112. The blow-by gas is introduced in the opening. The ECU 130 adjusts the blow-by gas flow rate with a PCV valve 118 provided in the middle of the discharge path 116. The configuration in which the fuel injection valve directly injects fuel into the cylinder, and the air cleaner 108, the PCV valve 118, the accelerator pedal 122, the accelerator sensor 124, the internal combustion engine speed sensor 126, and the vehicle speed sensor 128 are the same as those in the first embodiment. Are the same.

  With such a configuration, the ECU 130 in the above-described target PCV flow rate setting process (FIG. 2), the target intake cam working angle θt in step S106, the target intake valve maximum valve lift amount LFTt, and the intake cam working angle θ in step S108, The estimated intake pressure change amount dlmv is calculated using the throttle opening degree TA instead of the intake valve maximum valve lift amount LFT. Other processing is as described in the first embodiment.

  As a result, even in the configuration of FIG. 4, the same effect as in the first embodiment can be produced in the transient state of the operation of the internal combustion engine in which the accelerator pedal 122 is rapidly returned and rapidly decelerated.

[Other embodiments]
(A). In each of the embodiments described above, the estimated intake pressure change amount dlmv is calculated and determined, but instead, in step S108, the change amount of the blow-by gas flow rate may be calculated as a transient state of the internal combustion engine operation. When the amount of change in the blowby gas flow rate is larger than the reference value, the processes in steps S114 and S116 are performed.

  (B). In each of the above embodiments, the target PCV flow rate reduction correction amount cqpcv is calculated (S114) and the target PCV flow rate is corrected (S116). In addition, in step S114, the opening correction amounts of the PCV valves 18 and 118 are calculated. In step S116, the opening degree of the PCV valves 18 and 118 may be corrected by reducing the opening degree correction amount.

  Further, as the blow-by gas adjusting means, the opening degree PCVa of the PCV valves 18 and 118 is adjusted based on the target PCV flow rate qpcv, but the target PCV valve opening degree is calculated from the operating state of the internal combustion engine, and this target You may adjust the opening degree PCVa of the PCV valves 18 and 118 so that it may become a PCV valve opening degree.

1 is a block diagram illustrating a schematic configuration of an internal combustion engine control device according to a first embodiment. 4 is a flowchart of target PCV flow rate setting processing executed by the ECU according to the first embodiment. 3 is a timing chart showing an example of control in the first embodiment. FIG. 3 is a block diagram illustrating a schematic configuration of an internal combustion engine control device according to a second embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 2 ... Internal combustion engine, 4 ... Intake path, 6 ... Intake flow sensor, 8 ... Air cleaner, 10 ... Breather hose, 12 ... Intake manifold, 12a ... Branch path, 14 ... Variable valve operating device, 14a ... Valve lift amount sensor, 16 DESCRIPTION OF SYMBOLS ... Release route, 16a ... Release port, 18 ... PCV valve, 20 ... Transmission, 22 ... Accelerator pedal, 24 ... Accelerator sensor, 26 ... Internal combustion engine speed sensor, 28 ... Vehicle speed sensor, 30 ... ECU, 32 ... Accelerator pedal , 42 ... ECU, 102 ... internal combustion engine, 106 ... intake flow sensor, 108 ... air cleaner, 110 ... breather hose, 112 ... intake manifold, 112a ... surge tank, 114 ... throttle valve, 114a ... actuator, 114b ... throttle opening Sensor 116 ... Release path 118 ... PCV valve 122 Accelerator pedal, 126 ... engine speed sensor, 128 ... vehicle speed sensor, 130 ... ECU.

Claims (10)

A control device for an internal combustion engine provided with a blow-by gas reduction device that discharges blow-by gas to an intake system by adjusting a flow rate of blow-by gas continuously or stepwise by a blow-by gas adjusting valve,
An internal combustion engine transient state detecting means for detecting a transient state of the internal combustion engine operation;
When the internal combustion engine transient state detecting means detects that the internal combustion engine operation is in a transient state, a transient valve throttle means for reducing the opening of the blow-by gas adjusting valve;
An internal combustion engine control apparatus comprising: The internal combustion engine control apparatus according to claim 1, wherein the internal combustion engine control apparatus is a control apparatus for an internal combustion engine that injects fuel into a cylinder. 3. The internal combustion engine control device according to claim 1, wherein the control device is an internal combustion engine control device that adjusts an intake air amount sucked into a cylinder by adjusting a maximum valve lift amount of the intake valve. apparatus. The internal combustion engine control device according to any one of claims 1 to 3, wherein the internal combustion engine transient state detection means detects a change amount of intake pressure in a portion where blow-by gas is discharged as a transient state of the internal combustion engine operation. An internal combustion engine control device. The internal combustion engine control apparatus according to any one of claims 1 to 3, wherein the internal combustion engine transient state detecting means is a change amount of a blow-by gas flow accompanying a change in the operation state of the internal combustion engine as a transient state of the internal combustion engine operation. The internal combustion engine control apparatus characterized by detecting. 6. The internal combustion engine control device according to claim 4, wherein the internal combustion engine transient state detection means operates when the internal combustion engine operation is performed when the change amount is within a reference change amount region corresponding to a transient state of the internal combustion engine operation. Detecting that the engine is in a transient state. The internal combustion engine control apparatus according to any one of claims 1 to 6, wherein the transient valve throttle means is detected by the internal combustion engine transient state detection means that the internal combustion engine operation is in a transient state. In addition, the opening degree of the blow-by gas adjusting valve is reduced according to the degree of transient state of operation of the internal combustion engine. 8. The internal combustion engine control apparatus according to claim 1, wherein the transient valve throttle means is detected by the internal combustion engine transient state detection means that the internal combustion engine operation is in a transient state. An internal combustion engine control device that reduces the opening of the blow-by gas adjusting valve when the transient state of the operation of the internal combustion engine promotes an increase in the flow rate of blow-by gas. 9. The internal combustion engine controller according to claim 1, wherein the blow-by gas reduction device is configured to generate the blow-by gas based on an internal combustion engine speed, an internal combustion engine load, and a diluted state of the lubricating oil with fuel. Set the target value of the adjustment valve opening or the target value of the target blowby gas flow rate based on the opening of the blowby gas adjustment valve, and set the opening of the blowby gas adjustment valve to be this target value. An internal combustion engine control device comprising blowby gas adjusting means for adjusting. 10. The internal combustion engine control apparatus according to claim 9, wherein the transient valve throttle means sets a reduction correction amount in accordance with a transient state of the internal combustion engine operation detected by the internal combustion engine transient state detection means. An internal combustion engine control apparatus, wherein a target value in the blow-by gas adjusting means is reduced and corrected by a reduction correction amount.

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