JP3716601B2 - Control device for internal combustion engine for vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for a vehicle internal combustion engine, and more particularly to a control device for a vehicle internal combustion engine that controls the internal combustion engine in a vehicle equipped with an antilock brake system.
[0002]
[Prior art]
Some vehicles have an anti-lock brake system (ABS) to prevent the wheels from locking during braking. In the vehicle equipped with the antilock brake system, the internal combustion engine is controlled so that there is no adverse effect on the internal combustion engine when the antilock brake system is operated.
[0003]
In addition, in a vehicle, an EGR system that recirculates part of the exhaust gas of the internal combustion engine to the intake system, an evaporation system that controls the evaporated fuel (purge) to the intake system according to the operating state of the internal combustion engine, Each system includes an idle speed control system that controls the intake air flow rate when the engine is idling.
[0004]
Such a control device for an internal combustion engine is disclosed in, for example, Japanese Patent Application Laid-Open Nos. Hei 6-221200, Hei 8-86229, Hei 5-85334, and Hei 9-183364. Japanese Patent Application Laid-Open No. 6-221200 discloses that when an anti-skid brake device is actuated in a vehicle provided with an anti-skid rod brake device, the amount of intake air into the internal combustion engine is reduced. The value is increased from the value according to the operating state, thereby increasing the rotational speed of the internal combustion engine and making it difficult for the internal combustion engine to stall. Japanese Patent Laid-Open No. 8-86229 discloses a second device that varies torque based on a signal from a control unit, such as a device that increases or decreases the torque of an internal combustion engine in conjunction with an accelerator pedal, and a control system such as an AAC valve. The difference between the generated torque and the load torque is estimated from the change rate, and the torque to be compensated from the difference between the target rotation change rate and the actual rotation change rate. And the second device is controlled so as to give an electric signal according to the torque, and at the time of sudden braking, not only the drag torque increase due to the lockup release delay but also the generated torque corresponding to all the loads of the internal combustion engine To prevent the occurrence of engine stall. JP-A-5-85334 discloses a vehicle equipped with an anti-skid brake device provided with control means for starting ABS control when the wheel deceleration exceeds a predetermined deceleration threshold. And a start threshold value changing means for reducing and changing the deceleration threshold value so that the ABS control is started even when the wheel deceleration is small after a predetermined time has elapsed with the braking pressure applied to the wheel. Thus, when the brake pedal is depressed, the ABS control responds even when the wheel deceleration is relatively small while avoiding the start of the ABS control until the slip rate of the wheel settles to around 10 to 20%. It is designed to start well. Japanese Patent Application Laid-Open No. 9-183364 discloses an electromagnetic on-off valve structure in which one of an outlet or an inlet of a fluid is used as an opening and closing port, and the opening and closing port is opened and closed by operating in the fluid flow direction in the opening and closing port. A valve body, valve body urging means for urging the valve body in one direction of flow, and when energized, the valve body is operated in the other direction of flow against the urging force of the valve body urging means A solenoid, and a force acting means that acts on the valve body with a force that is opposite in direction to the force acting on the valve body due to the pressure of the fluid through the opening and closing port, and that has substantially the same magnitude. Regardless of the size, the closed state is stably maintained and the scale of the spring and solenoid that urges the valve body is reduced.
[0005]
[Problems to be solved by the invention]
By the way, in the case of a vehicle equipped with an anti-lock brake system, if the engine brake is too effective or the driving force of the internal combustion engine fluctuates when the anti-lock brake system is activated (on), the anti-lock brake system The lock brake control cannot be performed. In particular, when the engine brake is too effective, the wheels are locked, and the vehicle slides sideways and spins.
[0006]
In order to improve the controllability of the antilock brake control, the intake flow rate is corrected to increase the engine brake so that it is difficult to operate the engine. Depending on the gear position, the effect of the engine brake differs, which adversely affects the controllability of the antilock brake control, and in some cases, the vehicle spins.
[0007]
However, when the anti-lock brake system is operated, only the increase correction of the intake air flow rate is made uniform, so that there is a disadvantage that the braking performance by the anti-lock brake control cannot be ensured in every driving situation.
[0008]
Also, if the evaporation system is activated, the EGR system is activated, or the ignition timing is varied during the operation of the anti-lock brake system, the driving force of the internal combustion engine will fluctuate, adversely affecting the braking performance of the anti-lock brake system. There was an inconvenience of affecting.
[0009]
Furthermore, when the anti-lock brake system is in operation, the engine load changes more easily due to variations and durability due to the sliding state of the internal combustion engine, changes greatly due to atmospheric pressure, and when the engine load decreases, the engine brake is more effective. Therefore, there is a disadvantage that the controllability of the antilock brake control is greatly affected.
[0010]
[Means for Solving the Problems]
Therefore, the present invention eliminates the above-mentioned inconveniences by providing an anti-lock brake system that prevents the wheels from locking during braking, an EGR system that recirculates part of the exhaust gas of the internal combustion engine to the intake system, and the internal combustion engine. In a control apparatus for an internal combustion engine for a vehicle comprising an evaporation system that controls the amount of evaporated fuel to the intake system in accordance with the operating state of the engine, the EGR system and the evaporation system are operated when the antilock brake system is operated. Control means for stopping the operation of at least one of the systems is provided . The control means controls the ignition timing of the internal combustion engine to advance or retard, and controls the ignition timing of the internal combustion engine when the antilock brake system is operated. It is characterized by controlling to a fixed value .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
In the vehicle equipped with the anti-lock brake system, at least one of the EGR system and the evaporation system is stopped during the operation of the anti-lock brake system, and the ignition timing of the internal combustion engine is advanced. In addition to retarding control and controlling the ignition timing of the internal combustion engine to a fixed value during operation of the antilock brake system, the effectiveness of the engine brake is suppressed and the control accuracy of the antilock brake control is improved. Side slip and spin can be prevented.
[0012]
【Example】
Embodiments of the present invention will be described in detail and specifically with reference to the drawings. 1 to 6 show a first embodiment of the present invention. In FIG. 6, 2 is an internal combustion engine mounted on a vehicle, 4 is an intake manifold, 6 is an intake passage, 8 is a surge tank, 10 is a throttle body, 12 is a throttle valve, 14 is an intake pipe, 16 is an air cleaner, 18 is An exhaust manifold, 20 is an exhaust passage, 22 is an exhaust pipe, and 24 is a catalytic converter.
[0013]
The intake passage 6 is provided with a bypass air passage 28 that bypasses the throttle valve 12 so as to constitute an idle speed control system (ISC system) 26 that controls the intake flow rate during the idling operation of the internal combustion engine 2. ing. The bypass air passage 28 is provided with an idle air adjusting screw 30. Further, an idle air passage 32 communicates with the bypass air passage 28 so as to bypass the idle air adjusting screw 30. The idle air passage 32 is provided with an electromagnetically operated idle control valve (ISC valve) 34.
[0014]
A pressure introduction passage 36 communicates with the surge tank 8. A pressure sensor 38 is provided in the pressure introduction passage 36.
[0015]
A fuel injection valve 40 is attached to the internal combustion engine 2.
[0016]
The fuel injection valve 40 constitutes a fuel supply system 42 and communicates with a fuel tank 46 through a fuel supply passage 44. A fuel filter 48 is provided in the fuel supply passage 44. A fuel return passage 50 is connected to the fuel supply passage 44. A fuel pressure regulator 52 is provided in the fuel return passage 50. The fuel pressure regulator 52 is connected to a regulator pressure passage 54 for introducing the intake pipe pressure from the surge tank 8. The fuel tank 46 is provided with a fuel pump 56 and a fuel level sensor 58 that communicate with the fuel supply passage 44.
[0017]
The internal combustion engine 2 is provided with a PCV valve 60. A blow-by gas passage 62 communicating with the surge tank 8 is connected to the PCV valve 60.
[0018]
Between the internal combustion engine 2 and the fuel tank 46, first and second evaporation systems 64 and 66 are provided as an evaporation system that controls the amount of evaporated fuel (purge amount) to the intake system in accordance with the operating state of the internal combustion engine 2. It has been.
[0019]
In the first evaporation system 64, a first canister 72 is provided between a first evaporation passage 68 that communicates with the fuel tank 46 and a first purge passage 70 that communicates with the surge tank 8. A first tank internal pressure control valve 74 is provided in the passage 68, and a first purge valve 76 that is electromagnetically operated is provided in the first purge passage 70.
[0020]
In the second evaporation system 66, a second canister 82 is provided between a second evaporation passage 78 communicating with the fuel tank 46 and a second purge passage 80 communicating midway with the first purge passage 70. 78 is provided with a second tank internal pressure control valve 84, this second tank internal pressure control valve 84 is provided with an operating pressure passage 86 communicating with the pressure introduction passage 36, and a solenoid vacuum valve 88 is provided in this operating pressure passage 86. It has been. The second purge passage 80 is provided with a second purge valve 90 that operates electromagnetically. Further, a diagnostic communication passage 92 communicating with the intake passage 6 on the upstream side of the throttle valve 12 is provided in the second purge passage 80 between the second canister 82 and the second purge valve 90. The diagnostic communication passage 92 is provided with an evaporation diagnostic valve 94. The second canister 82 is provided with a canister air valve 96. In the second evaporation system 66, a tank internal pressure sensor 98 is provided in the fuel tank 46.
[0021]
Between the surge tank 8 and the exhaust passage 20, an EGR passage 102 of the EGR system 100 that recirculates a part of the exhaust gas of the internal combustion engine 2 to the intake system is provided. An EGR control valve 104 is provided in the EGR passage 102.
[0022]
The pressure sensor 38, the fuel pump 56, the fuel level sensor 58, the first purge valve 76, the solenoid vacuum valve 88, the second purge valve 90, the canister air valve 96, the tank internal pressure sensor 98, and the EGR control valve 104 are control means ( ECM) 106.
[0023]
The control means 106 includes an intake air temperature sensor 108 provided in the air cleaner 16, an intake air amount sensor 110 provided in the intake pipe 14, a throttle sensor 112 provided in the throttle body 10, and a cooling provided in the internal combustion engine 2. Water temperature sensor 114, front oxygen sensor 116 provided in exhaust manifold 18, rear oxygen sensor 118 provided in exhaust pipe 22 downstream of catalytic converter 24, crank angle sensor 120, and range position for automatic transmission Switch 122, air conditioner system 124, vehicle speed sensor 126, power steering pressure switch 128, diagnostic switch terminal 130, test switch terminal 132, ignition switch 134, shift switch 136, starter switch 138, main fuse 140 and the battery 142 communicate with each other. There.
[0024]
Further, an ignition coil 148 of an ignition timing control system 146 attached to a spark plug 144 provided in the internal combustion engine 2 communicates with the control means 106.
[0025]
Furthermore, the control means 106 is in communication with an anti-lock brake stem 150 that prevents the wheels from locking when the vehicle is braked.
[0026]
Thereby, the control means 106 inputs various signals and stops the operation of at least one of the EGR system 100 and the first and second evaporation systems 64 and 66 when the antilock brake system 150 is operated. is there.
[0027]
Further, the control means 106 controls the operation of the idle speed control system 26 so that the air flow rate is increased and corrected at least initially when the anti-lock brake system 150 is operated.
[0028]
Further, the control means 106 controls the advance / retard of the ignition timing of the internal combustion engine 2, and operates the ignition timing control system 146 when the antilock brake system 150 is operated, as shown in FIG. Is controlled to a fixed value.
[0029]
Furthermore, the control means 106 controls the operation of the idle speed control system 26 according to the vehicle speed when the antilock brake system 150 is operated.
[0030]
The control means 106 controls the operation of the idle speed control system 26 so that the intake air flow rate is corrected to increase in accordance with the engine load.
[0031]
Next, the operation of the first embodiment will be described based on the flowchart of FIG. 1 and the time chart of FIG.
[0032]
When the program is started in the control means 106 (step 202), it is first determined whether or not the antilock brake system 150 is activated (ON) (step 204).
[0033]
If this step 204 is YES, in the first embodiment, the operations of the first and second evaporation systems 64 and 66 and the EGR system 100 are forcibly stopped (indicated by S in FIG. 2). The start signals of the first and second evaporation systems 64 and 66 and the EGR system 100 are not accepted (step 206). Thus, when the anti-lock brake system 150 is operated, the exhaust gas recirculation and the supply of the evaporated fuel (purge) are not performed.
[0034]
Then, as the ignition timing control of the internal combustion engine 2, the ignition timing is controlled to a fixed value (first plan) (step 208). This is because when the ignition timing is advanced, the engine speed increases, while when the ignition timing is retarded, the engine speed decreases, so that the change in the ignition timing becomes a fluctuation in the driving force of the internal combustion engine 2 as it is. Because.
[0035]
Next, as a first proposal of intake flow rate control, the idle speed control system 26 is operated so as to control the intake flow rate (ISCV) in accordance with the vehicle speed (step 210). This intake flow rate (ISCV) is set according to the vehicle speed, as shown in FIG.
[0036]
The intake air flow rate (ISCV) is corrected by the engine load as shown in FIG. 4 (step 212). This is because the engine brake increases its movement when the engine load is small. That is, as shown in FIG. 4, a correction coefficient (ISCRL) of the intake air flow rate when the antilock brake system 150 is operated is obtained according to the engine load, and the intake air flow rate = ISCV × (1 + ISCLL) is calculated.
[0037]
Then, as shown in FIG. 5, an initial intake flow rate correction coefficient (ISCi) is obtained according to the time from when the antilock brake system 150 is operated, and then the above-described intake flow rate is corrected by this correction coefficient (ISCi). (Step 214). That is, the intake air flow rate (ISCABS) is calculated by ISCABS = ISCV × (1 + ISCL) × ISCi. This is because, if the wheel is locked by the engine brake at the initial stage of the operation of the anti-lock brake system 150 or the like, no matter how the anti-lock brake control is performed thereafter, the side slip of the vehicle cannot be stopped. This is to increase the intake air flow rate so that the engine brake does not work reliably.
[0038]
Then, the intake air flow rate (ISCABC) is used to control the intake air flow rate to the internal combustion engine 2 (step 216), and the program is ended (step 218).
[0039]
On the other hand, if the anti-lock brake system 150 is not activated in step 204, the program is immediately ended (step 218).
[0040]
As a result, when the anti-lock brake system 150 is operated, the operation of the EGR system 100 and the first and second evaporation systems 64 and 66 are stopped, thereby suppressing the effectiveness of the engine brake and improving the control accuracy of the anti-lock brake control. Can be improved.
[0041]
Further, by suppressing the effectiveness of the engine brake, it is possible to prevent the vehicle from slipping or causing spin.
[0042]
7 to 9 show a second embodiment of the present invention.
[0043]
In the following embodiments, the same reference numerals are given to the portions that perform the functions of the first embodiment described above.
[0044]
The features of the second embodiment are as follows. That is, as a second proposal of the ignition timing control, as shown in FIG. 7, the ignition timing is set to a value higher than the idle ignition timing by a set time (t ₁ ) from when the antilock brake system 150 is operated. The value is fixed (step 302). Then, as shown in FIG. 9, after the set time (t ₁ ) has elapsed, the ignition timing is slowly shifted to the idle ignition timing or another fixed value over time (t ₂ ) (step 304).
[0045]
Alternatively, as a third proposal of the ignition timing control, as shown in FIG. 8, the partial ignition timing is used as the ignition timing for the set time (t ₁ ) from the time of operation of the antilock brake system 150 (step 402), and As described above, after the set time (t ₁ ) has elapsed, the ignition timing is slowly shifted to the idle ignition timing or other fixed value over time (t ₂ ) (step 404).
[0046]
According to the configuration of the second embodiment, the same effect as that of the first embodiment described above can be obtained, and the ignition brake can be effectively controlled in the initial stage of the antilock brake system 150 by finely controlling the ignition timing. Can be suppressed.
[0047]
10 and 11 show a third embodiment of the present invention.
[0048]
The features of the third embodiment are as follows. That is, as a second proposal of intake flow rate control, as shown in FIG. 10, an intake flow rate (ISCNE) corresponding to the engine speed is obtained from the map of FIG. 11 (step 502), and this intake flow rate (ISCNE) is calculated. It is corrected with the engine load (ISCNEX (1 + ISCRL)) (step 504), and then the intake air flow rate is corrected with the correction coefficient (ISCi) from when the antilock brake system 150 is operated (step 506). That is, the intake air flow rate (ISCABC) is calculated by ISCABS = ISCNE × (1 + ISCRL) × ISCi.
[0049]
According to the configuration of the third embodiment, the same effect as that of the first embodiment can be obtained, and the intake air flow rate can be controlled even at the engine speed to effectively suppress the effect of the engine brake.
[0050]
In the present invention, the internal combustion engine 2 can be controlled by combining the first to third proposals for ignition timing control and the first and second proposals for intake flow rate control, respectively, as desired.
[0051]
【The invention's effect】
According to the present invention as apparent from the detailed description above, in the vehicle having an antilock braking system to stop the operation of at least one system of the EGR system and the evaporative system during operation of anti-lock braking system, also The ignition timing of the internal combustion engine is advanced / retarded, and when the antilock brake system is activated, the ignition timing of the internal combustion engine is controlled to a fixed value, thereby suppressing the effectiveness of the engine brake and antilock brake control. In addition to improving the control accuracy of the vehicle, it is possible to prevent the vehicle from slipping or spinning.
[Brief description of the drawings]
FIG. 1 is a flowchart of control of an internal combustion engine in a first embodiment.
FIG. 2 is a time chart of control of the internal combustion engine in the first embodiment.
FIG. 3 is a diagram for setting an intake air flow rate when the anti-lock brake system is operated according to the vehicle speed.
FIG. 4 is a diagram for setting a correction coefficient for the intake air flow rate when the antilock brake system is operated according to the engine load.
FIG. 5 is a diagram for setting a correction coefficient for an initial intake air flow rate when the antilock brake system is activated according to time.
FIG. 6 is a system configuration diagram of a control device for an internal combustion engine.
FIG. 7 is a flowchart for fixing an ignition timing to a value higher than an idle ignition timing (another fixed value) in the second embodiment.
FIG. 8 is a flowchart using a partial ignition timing as an ignition timing in the second embodiment.
FIG. 9 is a time chart of control of the internal combustion engine in the second embodiment.
FIG. 10 is a flowchart for controlling the intake air flow rate according to the engine speed in the third embodiment.
FIG. 11 is a diagram for setting the intake air flow rate according to the engine speed in the third embodiment.
[Explanation of symbols]
2 Internal combustion engine 26 Idle rotation speed control system 64 First evaporation system 66 Second evaporation system 100 EGR system 106 Control means 146 Ignition timing control system 150 Anti-lock brake system

Claims (3)

An anti-lock brake system that prevents the wheels from locking during braking, an EGR system that recirculates part of the exhaust gas of the internal combustion engine to the intake system, and the amount of evaporated fuel to the intake system according to the operating state of the internal combustion engine the control apparatus for an internal combustion engine for a vehicle and a evaporation system for controlling is provided with control means for stopping the operation of at least one system with the anti-lock braking system wherein the EGR system and the evaporative system during operation of the The control means controls the ignition timing of the internal combustion engine to advance or retard, and controls the ignition timing of the internal combustion engine to a fixed value when the antilock brake system is operated . Control device. The control means sets the ignition timing of the internal combustion engine to an advance side with respect to the idle ignition timing for a set time during the operation of the anti-lock brake system , and then returns to the idle ignition timing. The control device for an internal combustion engine for a vehicle according to claim 1 . The control means uses a partial ignition timing as the ignition timing of the internal combustion engine for a set time during the operation of the antilock brake system , and then returns the ignition timing of the internal combustion engine to an idle ignition timing. The control device for an internal combustion engine for a vehicle according to claim 1 .

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