JP2008280916A - Internal combustion engine control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an internal combustion engine control system ensuring effect of engine brake by limiting the closing velocity of a throttle valve as a surge countermeasure during deceleration even when intake pressure downstream of a supercharger is released to an engine side in an internal combustion engine having the supercharger. <P>SOLUTION: When the closing velocity of the throttle valve 9 is limited as the surge countermeasure in deceleration, a drive signal for stopping fuel injection is sent to an injector 3 attached to each cylinder according to predetermined setting from an ECU 50 so that the output torque of an engine 1 is reduced and the effect of engine brake is ensured. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an internal combustion engine control apparatus that controls a throttle opening by an electronic throttle valve in an internal combustion engine mounted on a vehicle, and more particularly to an internal combustion engine control apparatus that includes a supercharger.

  Generally, in an internal combustion engine (engine) equipped with a supercharger, when the throttle valve is closed during deceleration, the turbocharger continues high rotation for a while with the inertial force until immediately before. The intake pressure of the engine suddenly increases, and the compressor may generate surging (surge) and generate abnormal noise (surge noise).

Therefore, conventionally, as a measure for avoiding a surge during deceleration and an abnormal noise (surge noise) at the time of occurrence of a surge in an internal combustion engine with a turbocharger, between the upstream side and the downstream side of the compressor of the turbocharger. A device has been proposed in which a bypass passage (air bypass pipe) and its opening / closing valve (air bypass valve) are provided and the bypass passage is opened during deceleration to release the intake pressure downstream of the turbocharger upstream. (For example, see Patent Document 1).
In addition, a conventional device has been proposed in which a throttle valve is opened during deceleration to release the intake pressure downstream of the supercharger to the engine side (see, for example, Patent Document 2).

JP 2003-97298 A Japanese Patent Laid-Open No. 11-351030

In the conventional internal combustion engine control device, in the case of Patent Document 1, an air bypass pipe and an air bypass valve are provided as a countermeasure against surge in an internal combustion engine with a supercharger, but the intake pressure downstream of the compressor is rapidly increased. As a result, the surge may occur before the air bypass valve opens. Therefore, as a countermeasure, the throttle valve closing speed is limited before the air bypass valve is opened. However, depending on the closing speed, there is a problem that the effect of the engine brake cannot be secured. .
In the case of Patent Document 2, the throttle valve closing speed is limited during deceleration. However, since it is difficult to optimally set the throttle valve closing speed, depending on the closing speed, the engine brake There was a problem that it was not possible to ensure the effectiveness of.

  The present invention has been made in order to solve the above-described problems, and at the time of deceleration in an internal combustion engine with a supercharger, the closing speed of the throttle valve is set within a range in which the intake pressure downstream of the supercharger does not cause a surge. An object of the present invention is to obtain an internal combustion engine control device capable of ensuring the effectiveness of an engine brake when regulating.

  An internal combustion engine control apparatus according to the present invention includes a throttle valve for adjusting the amount of intake air supplied to a combustion chamber of the internal combustion engine, and a fuel injection amount calculation means for calculating a fuel injection amount according to the operating state of the internal combustion engine. , An electronically controlled fuel injection device for injecting fuel into each cylinder of the internal combustion engine, an injection control means for controlling the fuel injection device in accordance with the fuel injection amount, and an opening of the throttle valve in accordance with the operating state In an internal combustion engine control device comprising: an electronic throttle control means; a closing speed correction means for correcting the closing speed of the throttle valve to be reduced; and a deceleration state detection means for detecting a deceleration state of the internal combustion engine. The fuel injection setting means includes a fuel injection setting means, which restricts the closing speed of the throttle valve to be small when the internal combustion engine is decelerated. , Each for controlling one of the fuel injectors corresponding to respective cylinders, and sets whether to stop the fuel injection.

  According to the present invention, at the time of restricting the closing speed of the throttle valve for suppressing the surge during deceleration, the fuel injection is stopped at a predetermined rate (intermittent fuel cut is performed) each time the fuel injection device is controlled. The effectiveness of the brake can be secured.

Embodiment 1 FIG.
Hereinafter, the first embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram schematically showing the entire system of an internal combustion engine control apparatus according to Embodiment 1 of the present invention, and schematically shows the case of an internal combustion engine having a supercharger.

  In FIG. 1, an intake pipe 8 (intake system) is communicated with a combustion chamber 18 of an engine (internal combustion engine) 1 via an intake port 2 having an intake valve and an intake manifold 4 and exhaust having an exhaust valve. An exhaust pipe 17 (exhaust system) communicates with the port 13 and the exhaust manifold 15. A spark plug 20 driven by an ignition coil 19 is provided in the combustion chamber 18.

The engine 1 is provided with a plurality of cylinders, and an intake system and an exhaust system communicate with the combustion chamber 18 for each cylinder. In FIG. 1, only one cylinder is shown for convenience. .
In the vicinity of the intake port 2, an injector (fuel injection device) 3 for injecting fuel into intake air to form an air-fuel mixture is provided. The electronically controlled injector 3 is driven and controlled by a drive signal from the ECU 50 and injects fuel into each cylinder of the engine 1.

The engine 1 is provided with a coolant temperature sensor 22 that detects the coolant temperature and a crank angle sensor 23 that outputs a pulse signal synchronized with the rotation of the crankshaft.
An accelerator pedal operated by a driver of a vehicle (not shown) is provided with an accelerator position sensor (hereinafter abbreviated as “APS”) 24 that detects the depression amount of the accelerator pedal as an accelerator opening. Yes.

  The intake pipe 8 is opened and closed by an air cleaner 5 for purifying the intake air, an intake air temperature sensor 6 for detecting the intake air temperature, an air amount sensor 7 for detecting the intake air amount, and an electronic throttle actuator 12. And a throttle position sensor (hereinafter abbreviated as “TPS”) 10 for detecting the opening of the throttle valve 9 as the throttle opening.

The exhaust pipe 17 is provided with an O2 sensor 14 for detecting the air-fuel ratio of the air-fuel mixture supplied into the combustion chamber 18 and a three-way catalyst 16 for purifying the exhaust gas.
Further, the intake pipe 8 and the exhaust pipe 17 include a turbocharger 34 composed of a turbine 32 in the intake pipe 8 and a compressor 33 in the exhaust pipe 17 as elements constituting a supercharger, and a waste gate that drives the turbine 32. An actuator 36, a waste gate solenoid valve 39 for driving the waste gate actuator 36, an intercooler 40 provided in the intake pipe 8, an air bypass pipe 41 and an air bypass valve 42 are provided.

The waste gate solenoid valve 39 is connected to a pair of air pipes communicating with the upstream side and the downstream side of the compressor 33, and is opened and closed under the control of the ECU 50.
The air bypass pipe 41 and the air bypass valve 42 bypass the downstream side of the intercooler 40 disposed on the downstream side of the compressor 33 and the upstream side of the intake pipe 8.
In other words, the air bypass pipe 41 and the air bypass valve 42 interposed in the air bypass pipe 41 return the air pressurized by the compressor 33 from the downstream side to the upstream side of the compressor 33. As will be described later, the air bypass pipe 41 and the air bypass valve 42 may be omitted.

  Detection signals of the various sensors (intake air temperature sensor 6 and the like) are input to an engine control unit (hereinafter abbreviated as “ECU”) 50, and various actuators (injector 3 and the like) are driven under the control of the ECU 50. . In addition, an air conditioner control unit (hereinafter abbreviated as “ACU”) 51 for controlling an air conditioner is connected to the ECU 50.

  In the configuration of FIG. 1, a throttle valve 9 for adjusting the amount of intake air supplied to the combustion chamber 18 is interposed in the intake pipe 8 upstream of the intake manifold 4 communicating with the combustion chamber 18 of the engine 1. A throttle actuator 12 (having a DC or AC motor) is connected to the valve shaft of the throttle valve 9. The throttle actuator 12 is controlled by the ECU 50 so that the flow rate of air supplied to the combustion chamber 18 is adjusted to an amount corresponding to the accelerator opening.

FIG. 2 is a functional block diagram showing a specific configuration of the ECU 50.
In FIG. 2, the ECU 50 includes an ignition timing correction unit 61 including an ignition timing setting unit, an electronic throttle control unit 62 that drives and controls the throttle actuator 12, a deceleration state detection unit 63 that detects a deceleration state of the engine 1, and a deceleration A closing speed correcting means 64 for correcting the closing speed of the throttle valve 9 to be small, an injection control means 65 for driving the injector 3, and an external load detecting means 71 for detecting the state of the ACU 51 (external load). I have.

  The electronic throttle control means 62 drives the throttle actuator 12 and controls the opening degree of the throttle valve 9 according to the operating state acquired from the various sensors 60 and the APS 24.

  The injection control means 65 includes a feedback control means 66 for feedback control of the air-fuel ratio, a fuel cut control means 67 for performing fuel cut for all cylinders of the engine 1, and a fuel injection setting means having a stop ratio setting means 69. 68 and injector driving means 70 for driving the injector 3.

  The feedback control means 66 includes a fuel injection amount calculation means for calculating a fuel injection amount corresponding to the operating state of the engine 1 acquired from the various sensors 60, and the air-fuel ratio detection value from the O2 sensor 14 is a target air-fuel ratio (fuel). The injector 3 is driven via the injector driving means 70 so as to coincide with the injection amount), and the air-fuel ratio corresponding to the fuel injection amount is feedback controlled.

  The fuel cut control means 67 performs fuel cut for all cylinders under a predetermined condition when the accelerator opening degree indicates that the accelerator is fully closed.

The fuel injection setting means 68 controls one of the injectors 3 corresponding to each cylinder under a predetermined condition when the closing speed of the throttle valve 9 is limited to be small when the engine 1 is decelerated. Each time, whether to stop the fuel injection is set.
Further, the fuel injection setting means 68 is configured to alternately repeat the fuel injection and the fuel injection stop every time one of the injectors 3 corresponding to each cylinder is controlled in the control of the injector 3.

  The stop ratio setting means 69 in the fuel injection setting means 68 is related to the closing speed correction means 64 and the external load detection means 71 in order to set the ratio at which fuel injection is stopped under a predetermined condition. When the state detection means 63 is detecting a deceleration state and the closing speed correction means 64 restricts the closing speed of the throttle valve 9 to be small, the fuel injection is stopped according to the magnitude of the external load. Set the percentage.

  The stop ratio setting unit 69 includes an output torque calculating unit that calculates an output torque based on the throttle opening from the TPS 10 and a target torque calculating unit that calculates a target torque based on the accelerator opening from the APS 24. The ratio for stopping the fuel injection is set according to the ratio between the target torque calculated from the accelerator opening and the output torque calculated from the throttle valve opening.

Further, the stop ratio setting means 69 is related to the fuel cut control means 67. When the deceleration rate is limited so that the closing speed of the throttle valve 9 is reduced during deceleration, the stop ratio setting means 69 indicates the ratio at which fuel injection is stopped. Change before and after fuel cut for all cylinders when fully closed.
Further, the stop ratio setting means 69 gradually changes the ratio at which the fuel injection is stopped when limiting the closing speed of the throttle valve 9 to be small during deceleration.

  The feedback control means 66 in the injection control means 65 performs feedback control of the fuel amount so that the detected value of the air-fuel ratio coincides with the target value in normal times, and every time the fuel injection setting means 68 controls the injector 3. When it is set whether or not to stop fuel injection, the feedback control of the fuel amount (air-fuel ratio) is prohibited.

The ignition timing correction means 61 calculates and corrects the ignition timing of each cylinder of the engine 1 according to the operating state acquired from the various sensors 60 described above, and controls the ignition coil 19.
The ignition timing correction means 61 is related to the fuel injection setting means 68 in the injection control means 65, and sets whether or not to stop the fuel injection every time the fuel injection setting means 68 controls the injector 3. When the engine is running, the ignition timing is corrected so that the output torque of the engine 1 matches the target torque.

Next, the basic operation of the supercharger including the turbocharger 34 will be described.
The air that flows in through the air cleaner 5 is pressurized by a compressor 33 that is coaxially coupled to a turbine 32 that is driven by exhaust. The pressurized air is cooled by the intercooler 40 and supplied to the combustion chamber 18 of each cylinder of the engine 1 through the throttle valve 9.

  The air bypass pipe 41 provided with the air bypass valve 42 allows the intake air pressurized by the compressor 33 to be recirculated from the downstream side of the compressor 33 to the upstream side of the compressor 33. This function works by the differential pressure between the downstream side and the upstream side of the compressor 33.

  When the throttle valve 9 is open, the pressure on the downstream side of the compressor 33 escapes to the combustion chamber 18 via the intake manifold 4, but when the throttle valve 9 is rapidly closed, the pressurized air on the downstream side of the compressor 33 escapes. Until the air bypass valve 42 opens and recirculates, the pressure of the air on the downstream side of the compressor 33 may exceed the surge limit and a surge may occur.

  Therefore, in order to suppress the occurrence of this surge, by restricting the closing speed of the throttle valve 9 at the time of deceleration, the pressurized air is released to the combustion chamber 18 to suppress the occurrence of the surge. Since the closing speed of the throttle valve 9 is limited, air exceeding the driver's request is supplied to the combustion chamber 18 during deceleration. Therefore, with the control as described above, the output of the engine 1 may increase beyond the driver's request, and sufficient engine braking effectiveness may not be ensured.

The basic control procedure according to the first embodiment of the present invention shown in FIGS. 1 and 2 will be described below with reference to the flowchart of FIG.
In the first embodiment of the present invention, as shown in FIG. 3, when the closing speed of the throttle valve 9 is limited during deceleration (step S6), a drive signal is transmitted to the injector 3 attached to each cylinder. In the case (step S7), the injection control means 65 determines whether or not to stop the fuel injection (step S9), and stops the fuel injection according to a predetermined setting in relation to the fuel injection setting means 68. By transmitting a drive signal (step S10) (hereinafter abbreviated as “intermittent fuel cut”), the output torque of the engine 1 is reduced to ensure the effectiveness of the engine brake.

  In FIG. 3, first, the electronic throttle control means 62 calculates the target throttle opening according to the operating state including the accelerator opening from the APS 24 (step S1), and the ignition timing correcting means 61 responds to the operating state. A fuel injection amount is calculated (step S2).

  Subsequently, the deceleration state detection means 63 determines whether or not the engine 1 is decelerating (step S3). If it is determined that the engine 1 is not decelerating (that is, NO), the processing routine of FIG. 3 is immediately terminated. To do.

On the other hand, if it is determined in step S3 that the vehicle is decelerating (that is, YES), the closing speed correction means 64 calculates a limiting value corresponding to the lower limit value for limiting the closing speed of the target throttle opening (step S3). S4), it is determined whether or not the target throttle opening is smaller than the limit value (step S5).
If it is determined in step S5 that the target throttle opening ≧ the limit value (that is, NO), it is not necessary to limit the target throttle opening, so the processing routine of FIG. 3 is immediately terminated.

  On the other hand, if it is determined in step S5 that the target throttle opening is smaller than the limit value (ie, YES), the closing speed correcting means 64 limits the target throttle opening to the limiting value in order to limit the closing speed of the throttle valve 9. (Step S6).

  Next, the injection control means 65 determines whether or not it is the control timing for the injector (fuel injection device) 3 (step S7), and if it is determined that it is not the control timing for the injector 3 (that is, NO), FIG. 3 processing routine is immediately terminated.

On the other hand, if it is determined in step S7 that it is the control timing of the injector 3 (that is, YES), it is subsequently determined whether or not the fuel cut by the fuel cut control means 67 is in progress (step S8).
If it is determined in step S8 that the fuel is being cut (that is, YES), the processing routine of FIG. 3 is immediately terminated.

  On the other hand, if it is determined in step S8 that the fuel is not being cut (that is, NO), it is subsequently determined whether or not the setting state by the fuel injection setting means 68 is that fuel injection is stopped (step S9).

If it is determined in step S9 that the fuel injection is stopped (ie, YES), the injection control means 65 transmits a drive signal for stopping the fuel injection to perform the intermittent fuel cut, and The drive signal is turned off (de-energized), fuel injection is stopped (step S10), and the processing routine of FIG. 3 is terminated.
On the other hand, if it is determined in step S9 that fuel injection is not stopped (that is, NO), fuel injection is performed (step S11), and the processing routine of FIG. 3 ends.

As described above, the effectiveness of the engine brake can be ensured by the basic processing routine of FIG.
However, according to the determination process of step S9 only, it depends only on the setting result of the fuel injection stop, so when the fuel injection stop ratio is excessively increased or when the cylinders that stop the fuel injection are concentrated on a specific cylinder In addition, vehicle body vibration may occur.

Next, the operation based on the fuel injection stop condition by the fuel injection setting means 68 according to the first embodiment of the present invention will be described with reference to the flowchart of FIG. 4 together with FIGS. Here, a case where the fuel injection setting unit 68 alternately performs fuel injection and fuel injection stop on one injector 3 will be described as an example.
In FIG. 4, the same processes (steps S1 to S8, S10 and S11) as those described above (see FIG. 3) are denoted by the same reference numerals, and detailed description thereof is omitted.

  In step S91 corresponding to the above-described step S9, the setting state is determined by the fuel injection setting means 68. If the determination result is fuel injection, the injector of the current control cylinder is set before proceeding to step S11. 3, it is determined whether or not the previous control state was fuel injection.

If it is determined in step S91 that the previous control is fuel injection (that is, YES), even if the fuel injection setting means 68 has set the fuel injection, the process proceeds to step S10 to stop the fuel injection.
On the other hand, if it is determined in step S91 that the previous control is not fuel injection (that is, NO), the process proceeds to step S11 to perform fuel injection.

  In this way, step S91 is applied instead of the above-described step S9, and whenever one of the injectors 3 corresponding to each cylinder is controlled in the control of the injector 3, each control of the injector 3 attached to each cylinder is controlled. It is determined whether or not the previous fuel injection has been performed. If the previous fuel injection has been performed, a drive signal for stopping the injection is transmitted (step S10). If the previous fuel injection has not been performed, the fuel injection is performed. The drive signal is transmitted (step S11).

As a result, fuel injection and fuel injection stop are executed alternately, so that the vehicle body vibration can be suppressed while ensuring the effectiveness of the engine brake.
Note that the determination function of step S91 and the function of alternately repeating fuel injection and fuel injection stop may be included in the fuel injection setting means 68.

Next, a specific operation by the stop ratio setting unit 69 according to the first embodiment of the present invention will be described with reference to the flowcharts of FIGS. 5 and 6 together with FIGS.
FIG. 6 specifically shows the fuel injection stop ratio setting process (step S16) in FIG.

  As described above, the stop ratio setting unit 69 sets the ratio of stopping fuel injection according to the ratio between the target torque calculated from the accelerator opening and the output torque calculated from the throttle valve opening, When the closing speed of the throttle valve 9 is limited to be small at the time of deceleration, the ratio of stopping the fuel injection is set according to the magnitude of the external load.

In FIG. 5, the detailed description of steps S1 to S11 similar to those described above (see FIG. 3) is omitted.
First, the stop ratio setting means 69 detects the accelerator opening (step S12), detects the throttle opening (step S13), and outputs the target torque based on the accelerator opening and the output torque based on the throttle opening (assumed value). ) Is calculated (step S14), and the process proceeds to step S1.

  Next, the electronic throttle control means 62 and the injection control means 65 calculate the target throttle opening and the fuel injection amount in steps S1 and S2, and then the ignition timing correction means 61 calculates the ignition timing (step S15). ), The deceleration state detection means 63 proceeds to the deceleration determination process in step S3.

  Thereafter, the above-described steps S3 to S7 are executed, and if it is determined in step S7 that it is the control timing of the injector 3 (that is, YES), the stop ratio setting means 69 sets the ratio for stopping the fuel injection. Is executed (step S16), and the process proceeds to step S8 and subsequent steps.

In FIG. 6 showing the stop ratio setting process (step S16), the stop ratio setting means 69 first acquires load information from the ACU 51 via the external load detection means 71 (step S161), and the air conditioner is turned on. It is determined whether or not there is (step S162).
In this case, the ECU 50 is connected to the ACU 51 that controls the air conditioner (which is an external load of the engine 1), and a signal indicating the driving state of the air conditioner is input from the ACU 51 to the ECU 50. The detecting means 71 can determine whether or not the air conditioner is being driven.

If it is determined in step S162 that the air conditioner is ON (that is, YES), the stop ratio setting means 69 sets the fuel injection stop ratio when the air conditioner is ON (step S163), and the processing routine of FIG. Exit.
On the other hand, if it is determined in step S162 that the air conditioner is OFF (ie, NO), the fuel injection stop ratio when the air conditioner is OFF is set (step S164), and the processing routine of FIG.

  As described above, the stop ratio setting means 69 sets a stop ratio according to the load state when the air conditioner is driven while the air conditioner is driven (step S163), and stops when there is no external load when the air conditioner is stopped. Since the ratio is set (step S164), the effectiveness of the engine brake at the time of deceleration can be ensured regardless of the driving state of the air conditioner.

As a technique for transmitting a drive signal for stopping fuel injection according to a predetermined stop ratio set by the stop ratio setting means 69 in the ECU 50, for example, the following can be applied.
That is, in step S9 in FIG. 5, the predetermined stop ratio (the number of cylinders) is compared with the number of cylinders that stopped the fuel injection, and when the number of cylinders that stopped the fuel injection is small, the fuel injection is stopped. This can be realized by transmitting a drive signal (step S10), and otherwise transmitting a drive signal for executing fuel injection (step S11).

Next, referring to the flowchart of FIG. 7 together with FIGS. 1, 2 and 5, the fuel ratio is controlled by the stop ratio setting means 69 according to Embodiment 1 of the present invention (for all cylinders when the accelerator is fully closed). The operation of setting the stop ratio at the time of fuel cut) will be described.
As described above, the stop ratio setting means 69 sets the ratio of stopping fuel injection to the fuel for all cylinders when the accelerator is fully closed when limiting the closing speed of the throttle valve 9 to be small during deceleration. Change before and after cutting.

FIG. 7 corresponds to step S16 in FIG.
In FIG. 7, first, the stop ratio setting means 69 determines whether or not the fuel cut control means 67 has executed a fuel cut when the accelerator is fully closed (step S165).

If it is determined in step S165 that the fuel cut at the fully closed state has been executed (that is, YES), the stop ratio setting means 69 sets the fuel injection stop ratio when the fuel cut is restored (step S166). The processing routine of FIG. 7 is terminated.
On the other hand, if it is determined in step S165 that the fuel cut when fully closed is not executed (that is, NO), the fuel injection stop ratio during deceleration is set (step S167), and the processing routine of FIG. Exit.

Thus, during the intermittent fuel cut (step S10 in FIG. 5), when it is determined in step S165 that the fuel cut when the accelerator is fully closed has been executed, the fuel injection stop ratio is set to the fuel cut execution rate. A setting value different from the previous output suppression setting value (step S166) is set (step S167).
As a result, since the rotational speed of the engine 1 decreases at the end of the fuel cut, it is possible to set the fuel injection stop ratio giving priority to the output torque of the engine 1 over the effectiveness of the engine brake. Abnormal decrease can be prevented.

Next, a specific change setting operation of the fuel injection stop ratio by the stop ratio setting means 69 according to Embodiment 1 of the present invention will be described with reference to the explanatory diagram of FIG.
As described above, the stop rate setting means 69 gradually changes the rate at which fuel injection is stopped when limiting the closing speed of the throttle valve 9 to be small during deceleration.

FIG. 8 shows a preset map. Whether or not fuel is injected into the sequentially controlled cylinders 1, 2,..., 28,. The fuel injection “1” is given.
That is, when the target of fuel cut is “1/4 cylinder cut”, the number of continuous injection cylinders n is increased from n = 6 in stages, n = 5, n = 4, n = 3, By gradually decreasing, the target “1/4 cylinder cut” state is achieved in the control cylinder 19 (see the bold line frame).

  Similarly, when the target of fuel cut is “1/3 cylinder cut”, the number of continuous injection cylinders n is changed from n = 6 in stages, n = 5, n = 4, n = 3. , N = 2 and gradually decreasing, the target “1/3 cylinder cut” state is reached in the control cylinder 23 (see the thick line frame).

  As shown in FIG. 8, the number of cylinders n from the start of intermittent fuel cut (cylinder 1 = “0”) to the next setting for stopping fuel injection is set to a predetermined fuel with all cylinders as initial values. By searching the map so as to gradually decrease until the injection stop ratio is reached, the fuel injection is performed so that the ratio at which fuel injection is gradually stopped from the start of intermittent fuel cut until the predetermined fuel injection stop ratio is changed. By setting whether or not to stop (step S9 in FIG. 5), it is possible to reduce the change in the effectiveness of the engine brake during deceleration.

Next, the change setting operation of the fuel injection stop ratio based on the accelerator opening and the throttle opening by the stop ratio setting means 69 according to Embodiment 1 of the present invention will be described with reference to the explanatory diagram of FIG.
FIG. 9 shows a map example related to steps S14 and S16 described above (see FIG. 5). In FIG. 9, the horizontal axis corresponds to the target torque, the vertical axis corresponds to the calculated value (assumed value) of the output torque, and “A1, A2,..., A7” in the matrix indicate the fuel injection stop ratio (A1 < A2 <... <A7).

  As described above, the stop ratio setting means 69 receives signals indicating the accelerator opening and the throttle opening. The stop ratio setting means 69 is provided with target torque calculation means for calculating the driver's target torque from the accelerator opening, and output torque calculation means for calculating the output torque of the engine 1 from the throttle opening. .

  In step S14 described above, the output torque calculation means in the stop ratio setting means 69 calculates the output torque (assumed value) of the engine 1 that does not take into account the change in output torque due to the intermittent fuel cut based on the throttle opening.

In step S16, the stop ratio setting unit 69 obtains the stop ratio by searching the map of FIG.
In the map of FIG. 9, the target torque, the assumed output torque, and the fuel injection stop ratios A1 to A7 are associated in advance based on the ratio between the target torque and the output torque (assumed value). That is, when the assumed output torque with respect to the target torque is low, a small stop ratio A1 is set, and when the assumed output torque with respect to the target torque is high, a large stop ratio A7 is set.

  In this way, the driver requests the stop ratio setting means 69 to send a signal for stopping fuel injection to the injector drive means 70 for each stop ratio (number of cylinders) obtained by the stop ratio setting means 69. The effect of the engine brake can be secured.

  As shown in FIG. 1, the O 2 sensor 14 attached to the exhaust manifold 15 measures the air-fuel ratio of the air-fuel mixture supplied to the combustion chamber 18, and sends an air-fuel ratio detection signal to the feedback control means 66. You are typing. Thereby, the feedback control means 66 calculates the fuel correction amount corresponding to the air-fuel ratio based on the detection signal from the O2 sensor 14 in step S2 (see FIGS. 3 to 5) so that the fuel injection amount becomes appropriate. is doing.

However, as described above, during the intermittent fuel cut based on the stop ratio setting unit 69, the feedback control unit 66 makes the condition for obtaining the fuel correction amount from the air-fuel ratio measured by the O2 sensor 14 unsatisfied. Calculation of fuel correction amount by fuel ratio is prohibited.
Thereby, in the air-fuel mixture supplied to the combustion chamber 18 after the intermittent fuel cut, it is possible to avoid the deviation of the air-fuel ratio due to the stop of the fuel injection and to suppress the deterioration of the exhaust gas.

Next, referring to the flowchart of FIG. 10 and the explanatory diagram of FIG. 11 together with FIGS. 1 and 2, the ignition timing correction means 61 (ignition timing) related to the stop ratio setting means 69 according to the first embodiment of the present invention. The operation of (including setting means) will be described.
FIG. 11 shows a map of the ignition timing correction amount. The target torque (horizontal axis), output torque (vertical axis), and ignition timing retardation amounts C1 to C7 (| C1 | <| C2 | < .. <| C7 |).

In FIG. 10, first, the ignition timing correction means 61 (ignition timing setting means) sets a basic ignition timing based on the operating state acquired from the various sensors 60 (step S151), and corrects the ignition timing. Calculation is performed (step S152).
Subsequently, an ignition timing correction amount at the time of intermittent fuel cut by the stop ratio setting means 69 at the time of deceleration is set (step S153), and it is determined whether or not the current operation state is decelerating (step S154).

  At this time, the ignition timing correction means 61 stops the throttle valve 9 closing speed correction state during deceleration, the target torque based on the accelerator opening, and the output torque based on the throttle opening as shown in FIG. You may acquire via the ratio setting means 69, and may acquire directly from the closing speed correction | amendment means 64, APS24, and TPS10.

If it is determined in step S154 that the vehicle is not decelerating (that is, NO), the processing routine of FIG. 10 is immediately terminated.
On the other hand, if it is determined in step S154 that the vehicle is decelerating (that is, YES), the ignition timing correction amount at the time of deceleration is subtracted to retard the drive timing of the ignition coil 19 (ignition timing of the spark plug 20). (Step S155), and the processing routine of FIG.

  As described above, when the throttle valve 9 is closed in a deceleration state and the closing speed of the throttle valve 9 is limited (step S154), the intermittent fuel cut by the stop ratio setting unit 69 and the ignition timing by the ignition coil 19 and the spark plug 20 are delayed. By performing the angle control (step S155), the effectiveness of the engine brake can be ensured to the maximum.

  At this time, for example, by searching a map in which the target torque and output torque shown in FIG. 11 are associated with the retard amounts C1 to C7 of the ignition timing based on the target torque and the assumed output torque, the ECU 50 corrects the ignition timing correction amount. By setting (step S153), it is possible to ensure the effectiveness of the engine brake requested by the driver.

In FIG. 11, the ignition timing correction amounts C1 to C7 are positive values in the region above the primary correlation characteristic (see the broken line) between the target torque and the assumed output torque (see target torque <assumed output torque). It is a negative value in the region below the primary correlation characteristic (target torque> assumed output torque). That is, in the range of target torque> assumed output torque, the ignition timing is corrected to the advance side (output torque increase side) by the ignition timing correction amount subtraction process (step S155).
Thus, the ignition timing can be corrected so that the output torque of the engine 1 matches the target torque.

Further, according to the first embodiment of the present invention, even if the air bypass pipe 41 and the air bypass valve 42 in FIG. 1 are removed, the engine equivalent to the case where the air bypass pipe 41 and the air bypass valve 42 are provided. The effectiveness of the brake can be secured.
That is, the closing speed of the throttle valve 9 is limited (steps S5 and S6), and the pressurized air is released to the combustion chamber 18 via the throttle valve 9, thereby reducing the pressure on the downstream side of the compressor 33 and causing a surge. In addition, the fuel injection stop rate can be set appropriately by searching a map set in advance for, for example, pressurized air (step S16). Even if the air bypass pipe 41 and the air bypass valve 42 for releasing the intake pressure upstream of the supercharger are removed, the effect of the engine brake can be ensured.

  As described above, according to the first embodiment of the present invention, the throttle actuator 12 that opens and closes the throttle valve 9 on the downstream side of the turbocharger, and the basic throttle opening (target) according to the accelerator opening (detected value). Value) and electronic throttle control means 62 for adjusting and controlling the throttle actuator 12 so that the throttle opening (detected value) matches the target opening, and whether a deceleration condition for performing surge suppression control is satisfied Deceleration state detection means 63 for determining whether or not, an injection control means 65 for calculating the fuel amount according to the operating state, and the fuel injection is stopped every time the injector 3 (fuel injection device) attached to each cylinder is controlled. Fuel injection setting means 68 for setting whether or not to perform, and the fuel injection setting means 68 closes the throttle valve 9 for suppressing surge during deceleration. During degrees regulations, each for controlling the injector 3 of each cylinder, since fuel injection is stopped at a predetermined ratio, it is possible to ensure the effectiveness of the engine brake.

  Further, the fuel injection setting means 68 alternately sets the execution and stop of the fuel injection alternately for each cylinder every time the injector 3 is controlled when the closing speed of the throttle valve 9 for suppressing the surge during deceleration is restricted. Therefore, it is possible to suppress the vehicle body vibration of the vehicle equipped with the engine 1 and to ensure the effectiveness of the engine brake.

  Further, an external load detecting means 71 for detecting an external load of the engine 1 and a stop ratio setting means 69 for setting a fuel injection stop ratio are provided, and the fuel injection stop ratio during deceleration is set according to the external load. Therefore, even when the external load changes, every time the injector 3 is controlled, the fuel injection can be stopped at a rate corresponding to the external load, and the effectiveness of the engine brake can be ensured.

  The APS 24 detects the accelerator opening (the amount of depression of the accelerator pedal) and the fuel cut control means 67 that cuts the fuel of all cylinders when the accelerator is fully closed. The stop ratio setting means 69 suppresses surge during deceleration. When restricting the closing speed of the throttle valve 9 for the engine, the fuel injection stop ratio is set before and after the fully-closed fuel cut, and the engine brake is effective until the all-cylinder fuel cut is executed at the time of deceleration. Since the ratio of stopping the fuel injection after the release of the cut is set to a value different from that before the all-cylinder fuel cut, it is possible to suppress a decrease in the engine speed after the release of the all-cylinder fuel cut.

  Further, the stop ratio setting means 69 gradually changes the ratio of stopping the fuel injection every time the injector 3 attached to each cylinder is controlled when the closing speed of the throttle valve 9 for suppressing the surge during deceleration is restricted. Thus, since the output torque of the engine 1 is continuously changed, a more appropriate change in the deceleration feeling can be given.

  The stop ratio setting means 69 includes target torque calculation means for calculating target torque from the accelerator opening, and output torque calculation means for calculating output torque from the throttle opening, and a throttle valve for surge suppression during deceleration. 9, the fuel injection stop ratio is set according to the ratio between the target torque requested by the driver and the actual output torque (assumed value) of the engine 1. The effectiveness of the brake can be secured.

  The O2 sensor 14 for obtaining the air-fuel ratio of the air-fuel mixture supplied to the combustion chamber 18 and the feedback control means 66 for obtaining the fuel correction amount from the detected value of the air-fuel ratio are provided. The feedback control means 66 is a fuel based on the air-fuel ratio. It includes a fuel correction condition determining means for determining whether or not a condition for performing correction is satisfied, and the fuel injection setting means 68 satisfies a condition for setting whether or not to stop the fuel injection every time the injector 3 is controlled. In the period in which the presence or absence of fuel injection is set for each control of the injector 3, the condition for obtaining the fuel correction amount from the air-fuel ratio is not satisfied, Incorrect feedback learning of the air-fuel ratio in the feedback control means 66 due to the stop of fuel injection is inhibited, and deviation of the air-fuel ratio of the air-fuel mixture supplied into the combustion chamber is suppressed. Since, it is possible to a combustion state after shutting speed regulation of the throttle valve 9 and well maintained prevent deterioration of exhaust gas.

  In addition, an ignition timing correction unit 61 corresponding to the operating state is provided, and the fuel injection setting unit 68 determines whether or not a condition for setting whether or not to stop the fuel injection is satisfied each time the injector 3 is controlled. The ignition timing correction means 61 includes an injection condition determination means for determining, and sets the ignition timing appropriately when setting whether or not to stop the fuel injection for each control of the injector 3, so at a predetermined rate. While stopping fuel injection, the output torque of the engine 1 can be suppressed and the effectiveness of engine braking can be ensured to the maximum.

  Furthermore, by limiting the closing speed of the throttle valve 9 in a pressure region where the surge of the turbocharger does not occur and stopping the fuel injection at a predetermined rate to ensure the effectiveness of the engine brake, the downstream side of the turbocharger Since it is not necessary to return the supercharging pressure to the upstream side of the supercharger, in the engine 1 with the supercharger, the air bypass pipe 41 that releases the supercharged air downstream of the supercharger to the upstream side of the supercharger. In addition, the air bypass valve 42 can be omitted, and the cost can be reduced by reducing the number of parts for recirculation.

1 is a block configuration diagram schematically showing an entire system of an internal combustion engine control apparatus according to Embodiment 1 of the present invention. FIG. It is a functional block diagram which shows the specific structure of ECU which concerns on Embodiment 1 of this invention. It is a flowchart which shows the control action of ECU which concerns on Embodiment 1 of this invention. It is a flowchart which shows the control action of ECU which concerns on Embodiment 1 of this invention. It is a flowchart which shows the control action of ECU which concerns on Embodiment 1 of this invention. It is a flowchart which shows the setting operation | movement of the fuel-injection stop ratio according to the load condition which concerns on Embodiment 1 of this invention. It is a flowchart which shows the setting operation | movement of the fuel-injection stop ratio at the time of the fuel cut which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows an example of the fuel injection stop ratio which concerns on Embodiment 1 of this invention with a table | surface. It is explanatory drawing which shows the setting map of the fuel-injection stop ratio which concerns on Embodiment 1 of this invention. It is a flowchart which shows the ignition timing correction | amendment operation | movement at the time of the deceleration which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the correction amount map of the ignition timing which concerns on Embodiment 1 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Engine (internal combustion engine), 3 Injector (fuel-injection apparatus), 8 Intake pipe, 9 Throttle valve, 10 TPS (throttle position sensor), 12 Throttle actuator, 14 O2 sensor (air-fuel ratio detection means), 17 Exhaust pipe, 18 Combustion chamber, 19 ignition coil, 20 spark plug, 24 APS (accelerator position sensor), 32 turbine, 33 compressor, 34 turbocharger, 36 wastegate actuator, 39 wastegate solenoid valve, 40 intercooler, 41 air bypass pipe, 42 Air bypass valve, 50 ECU (engine control unit), 51 ACU (air conditioner control unit), 60 Various sensors, 61 Ignition timing correction means, 62 Electronic throttle control Stage, 63 deceleration state detection means, 64 closing speed correction means, 65 injection control means, 66 feedback control means (fuel injection amount calculation means), 67 fuel cut control means, 68 fuel injection setting means, 69 stop ratio setting means, 70 Injector driving means, 71 External load detecting means.

Claims (9)

A throttle valve for adjusting the amount of intake air supplied to the combustion chamber of the internal combustion engine;
Fuel injection amount calculation means for calculating a fuel injection amount according to the operating state of the internal combustion engine;
An electronically controlled fuel injection device that injects fuel into each cylinder of the internal combustion engine;
Injection control means for controlling the fuel injection device in accordance with the fuel injection amount;
Electronic throttle control means for controlling the opening of the throttle valve according to the operating state;
A closing speed correction means for correcting the throttle valve so that the closing speed becomes small;
An internal combustion engine control device comprising: deceleration state detection means for detecting a deceleration state of the internal combustion engine;
The injection control means includes fuel injection setting means,
When the fuel injection setting means restricts the closing speed of the throttle valve to be reduced when the internal combustion engine is decelerated, any one of the fuel injection devices corresponding to each cylinder under a predetermined condition An internal combustion engine control device that sets whether or not to stop fuel injection each time the control is performed.   The fuel injection setting means alternately repeats fuel injection and fuel injection stop every time one of the fuel injection devices corresponding to each cylinder is controlled in the control of the fuel injection device. Item 6. The internal combustion engine control device according to Item 1. An external load detecting means for detecting an external load of the internal combustion engine;
The fuel injection setting means includes a stop ratio setting means for setting a ratio for stopping fuel injection under the predetermined condition,
The stop ratio setting means sets the ratio of stopping the fuel injection according to the magnitude of the external load when the throttle valve closing speed is limited to be small at the time of deceleration. The internal combustion engine control device according to claim 1 or 2, characterized in that Accelerator opening detection means for detecting the amount of depression of the accelerator pedal as the accelerator opening,
The injection control means includes a fuel cut control means for performing fuel cut on all cylinders under a predetermined condition when the accelerator opening indicates when the accelerator is fully closed,
The fuel injection setting means includes a stop ratio setting means for setting a ratio for stopping fuel injection under the predetermined condition,
The stop ratio setting means sets the ratio of stopping the fuel injection when the throttle valve closing speed is reduced at the time of deceleration to determine the fuel cut for all cylinders when the accelerator is fully closed. The internal combustion engine control device according to claim 1 or 2, wherein the internal combustion engine control device is changed before and after.   The stop ratio setting means gradually changes the ratio at which the fuel injection is stopped when the throttle valve closing speed is limited to be small during the deceleration. The internal combustion engine control device according to claim 4. An accelerator opening detecting means for detecting the amount of depression of the accelerator pedal as an accelerator opening;
Throttle opening detection means for detecting the throttle valve opening as the throttle opening;
The stop ratio setting means sets a ratio for stopping the fuel injection according to a ratio between a target torque calculated from the accelerator opening and an output torque calculated from the throttle valve opening. The internal combustion engine control device according to any one of claims 3 to 5, wherein: Air-fuel ratio detection means for detecting the air-fuel ratio of the air-fuel mixture supplied into the combustion chamber,
The injection control means includes
During normal times, the fuel amount is feedback-controlled so that the detected value of the air-fuel ratio matches the target value,
2. The fuel amount feedback control is prohibited when the fuel injection setting means sets whether or not to stop fuel injection every time the fuel injection device is controlled. Item 7. The internal combustion engine control device according to any one of Items 6 to 6. Ignition timing correction means for correcting the ignition timing of each cylinder according to the operating state,
The ignition timing correcting means sets whether the output torque of the internal combustion engine coincides with a target torque when the fuel injection setting means sets whether or not to stop fuel injection every time the fuel injection device is controlled. The internal combustion engine controller according to any one of claims 1 to 7, wherein the ignition timing is corrected as described above.   The internal combustion engine control device according to any one of claims 1 to 8, further comprising a supercharger for supercharging air supplied into the combustion chamber.

Images