JP4409065B2 - Control device for engine idle control valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an engine idle control valve control device that optimizes the opening of an idle control valve during traveling.
[0002]
[Prior art]
In general, in order to maintain the engine idle speed at an optimum state, an idle control valve is provided in a bypass passage that bypasses the throttle valve, and the amount of intake air of the engine is controlled by controlling the opening of the idle control valve. The technology to adjust is widely adopted. For example, as disclosed in Japanese Patent Application Laid-Open No. Hei 5-19532 filed by the present applicant, the opening degree of the idle control valve is obtained by correcting the basic characteristic value determined by the engine temperature typified by the cooling water temperature with various correction terms. Is set.
[0003]
[Problems to be solved by the invention]
However, the required torque during idling tends to increase due to an increase in the size of driving accessories, etc., but the required torque can be satisfied by increasing the capacity of the idle control valve and increasing the air volume of the bypass passage. In an AT vehicle with a torque converter, there is a problem that the opening of the idle control valve becomes too large during deceleration and the intake pipe negative pressure becomes insufficient.
[0004]
In other words, when the brake booster decelerates, the assist force by the brake booster decreases relatively, increasing the pedaling force of the brake pedal, reducing the engine braking effect, and torque shock when returning from a fuel cut during deceleration The problem arises that becomes large.
[0005]
The present invention has been made in view of the above circumstances, and provides an engine idle control valve control device that can optimize the opening of an idle control valve during traveling and ensure intake pipe negative pressure during deceleration. The purpose is that.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an invention according to claim 1 is a control device for an engine idle control valve in which a transmission is connected to an output shaft of an engine via a torque converter, and the input shaft of the transmission is rotated. The torque converter correction amount considering the engine load due to the stirring resistance of the torque converter Separately when the air conditioner is activated and when the air conditioner is stopped A torque converter correction amount setting means to be set and a control amount for the idle control valve are corrected in a direction to decrease the opening of the idle control valve using the torque converter correction amount, and the opening of the idle control valve is controlled. And opening degree control means.
[0007]
According to a second aspect of the present invention, in the first aspect of the invention, the torque converter correction amount setting means sets the torque converter correction amount to a value corresponding to no correction below the creep vehicle speed region, and exceeds the creep vehicle speed. In the region, the torque converter correction amount is increased in response to an increase in the input shaft rotational speed of the transmission, and in the region where the input shaft rotational speed of the transmission is equal to or higher than a set rotational speed, the torque converter correction amount is set to a constant value. It is characterized by converging.
[0008]
According to a third aspect of the present invention, in the first or second aspect of the present invention, the torque converter correction amount setting means limits the upper limit of the torque converter correction amount with a restriction value set based on a vehicle speed. Features.
[0009]
According to a fourth aspect of the invention, in the first or second aspect of the invention, the torque converter correction amount setting means restricts the torque converter correction amount to an upper limit with a restriction value set based on the engine temperature. It is characterized by.
[0010]
According to a fifth aspect of the present invention, in the first or second aspect of the invention, the torque converter correction amount setting means is configured to determine the torque converter correction amount based on a regulation value set based on a vehicle speed and an engine temperature. The upper limit is regulated by the smaller one of the set regulation values.
[0011]
The invention described in claim 6 is the invention according to any one of claims 1, 2, 3, 4 and 5, wherein the torque converter correction amount setting means is ,Up Regulations to limit upper limit of torque converter correction amount The value It is characterized in that it is set separately corresponding to when the air conditioner is activated and when the air conditioner is stopped.
[0012]
That is, according to the first aspect of the present invention, the torque converter correction amount in consideration of the engine load due to the stirring resistance of the torque converter is calculated based on the input shaft speed of the transmission. Separately when the air conditioner is activated and when the air conditioner is stopped By setting and correcting the control amount for the idle control valve in the direction of decreasing the opening amount of the idle control valve using this torque converter correction amount, the opening amount of the idle control valve at the time of traveling is optimized, and Ensure intake pipe negative pressure.
[0013]
In this case, the invention according to claim 2 is that, if the vehicle speed is below the creep vehicle speed range, the torque converter correction amount is a value corresponding to no correction, and the intake pipe negative pressure is insufficient when the throttle valve is fully closed when the vehicle is stopped or in the creep running state. In the region where the effects of the intake pipe negative pressure shortage can be ignored, the torque converter correction amount is increased as the input shaft speed of the transmission increases in the region where the creep vehicle speed is exceeded. In a region where the input shaft rotational speed is higher than the set rotational speed and the engine is relatively high and the intake pipe negative pressure does not change so much, the torque converter correction amount is converged to a constant value to improve controllability. improves.
[0014]
According to a third aspect of the present invention, the torque converter correction amount is subjected to upper limit regulation with a regulation value set based on the vehicle speed, thereby preventing overcorrection in a range where the reduction ratio is larger than the normal shift range.
[0015]
The invention according to claim 4 prevents the overcorrection of the control amount of the idle control valve based on the engine temperature by restricting the torque converter correction amount to the upper limit with a restriction value set based on the engine temperature.
[0016]
According to the fifth aspect of the present invention, the torque converter correction amount is more restricted by restricting the torque converter correction amount to the upper limit with the smaller one of the restriction value set based on the vehicle speed and the restriction value set based on the engine temperature. By restricting the upper limit with a strict value, it is possible to reliably prevent overcorrection of the control amount of the idle control valve.
[0017]
The invention according to claim 6 The Regulations for limiting the converter's correction amount to the upper limit The value In addition, by setting separately corresponding to when the air conditioner is activated and when the air conditioner is stopped, it is possible to make an appropriate correction according to the difference in engine load between when the air conditioner is activated and when the air conditioner is stopped.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. 1 to 7 relate to an embodiment of the present invention, FIG. 1 is a schematic diagram of an engine and a drive system, FIG. 2 is a circuit configuration diagram of an electronic control system, FIG. 3 is a flowchart of an ISC control routine, and FIG. FIG. 5 is a flowchart of an AT vehicle torque converter correction amount setting routine, FIG. 6 is an explanatory diagram showing a change in torque converter stirring resistance, and FIG. 7 is a change in intake pipe negative pressure due to a decrease in ISC flow rate. It is explanatory drawing which shows.
[0019]
In FIG. 1, reference numeral 1 denotes an engine (in FIG. 1, an in-line four-cylinder natural intake type engine), and an intake manifold 3 communicates with each intake port 2 a formed in a cylinder head 2 of the engine 1. . An intake pipe 5 is communicated with the intake manifold 3 via an air chamber 4 in which intake passages of the respective cylinders gather, and an air cleaner 6 is attached to the intake air intake side of the intake pipe 5. The air chamber 4 communicates with a brake booster 8 having a master cylinder 7, and a brake pedal 9 is connected to the brake booster 8.
[0020]
In addition, a throttle valve 10 is interposed in the intake pipe 5, and the amount of bypass air flowing through the bypass passage 11 is adjusted to the bypass passage 11 that communicates the upstream side and the downstream side of the throttle valve 10 at the time of idling. Thus, an idle control valve (ISC valve) 12 for controlling the idle speed is interposed. In this embodiment, the ISC valve 12 is a linear solenoid valve, and the valve opening degree is adjusted according to a duty signal from an engine control electronic control device 50 (see FIG. 2) described later.
[0021]
In addition, an injector 13 is exposed immediately upstream of each intake port 2a of each cylinder of the intake manifold 3, and an ignition plug 14 is provided for each cylinder of the cylinder head 2 to expose the discharge electrode portion to the combustion chamber. Yes. An ignition coil 15 incorporating an igniter 16 is connected to the spark plug 14.
[0022]
Further, a catalytic converter 18 is interposed at a joining portion of the exhaust manifold 17 communicating with each exhaust port 2 b of the cylinder head 2 and communicated with the exhaust pipe 19. A sub-muffler 20 is disposed in the middle of the exhaust pipe 19, and a muffler 21 is disposed on the end side.
[0023]
On the other hand, a transmission 24 is connected to the crankshaft 1a of the engine 1 through a torque converter (torque converter) 23 having a lockup clutch 22 for engaging the impeller and the turbine. In this embodiment, the transmission 24 includes a primary pulley 26 that is connected to the torque converter 23 via a forward / reverse switching mechanism 25 including various hydraulic clutches, hydraulic brakes, and planetary gears. A continuously variable transmission including a secondary pulley 28 connected via a drive belt 27. A differential mechanism 30 is connected to an output shaft of the secondary pulley 28 via a reduction gear train 29, and is driven by the differential mechanism 30. Drive wheels 32 are provided continuously through a shaft 31.
[0024]
Next, various sensors for detecting the driving state will be described. As sensors mounted on the engine 1 side, the throttle valve 35 of the intake pipe 5 includes a throttle opening sensor 35a for detecting the throttle opening and an idle switch 35b that is turned on when the throttle valve is fully closed. Are connected. The air chamber 4 is provided with an intake pipe pressure sensor 36 for detecting the intake pipe pressure downstream of the throttle valve 10 with an absolute pressure.
[0025]
A knock sensor 37 is attached to the cylinder block 1 b of the engine 1, and a cooling water temperature sensor 38 is exposed to the cooling water passage 2 c provided in the cylinder head 2. A cam angle sensor 40 for detecting a crank angle and determining a cylinder is opposed to a signal rotor 39 connected to the cam shaft 2d of the cylinder head 2. Further, an O 2 sensor 41 is disposed immediately upstream of the catalytic converter 18.
[0026]
On the other hand, as the sensors mounted on the continuously variable transmission 24 side, a primary pulley rotational speed sensor 42 for detecting the transmission input shaft rotational speed is paired with the primary pulley 26. Further, the secondary pulley 28 is provided with a secondary pulley rotation speed sensor 43 for detecting the transmission output shaft rotation speed.
[0027]
Next, the configuration of the electronic control system that controls the engine and the drive system will be described with reference to FIG. First, an engine control electronic control unit (ECU) 50 includes a CPU 51, a ROM 52, a RAM 53, a backup RAM 54, a serial interface (SCI) 55, a counter / timer group 56, and an I / O interface 57 that are connected to each other via a bus line. Peripheral circuits such as a constant voltage circuit 58 for supplying a stabilized power supply to each part, a drive circuit 59 connected to the I / O interface 57, and an A / D converter 60 are built in, mainly including a connected microcomputer. ing.
[0028]
The counter / timer group 56 includes a free run counter, various counters such as a cylinder discrimination sensor signal (cylinder discrimination pulse) input counter, a fuel injection timer, an ignition timer, and a periodic interrupt for generating a periodic interrupt. Timers, timers for measuring input intervals of crank angle sensor signals (crank pulses), timers for measuring the elapsed time after engine startup, timers for measuring the time elapsed after startup, and watchdog timers for monitoring system abnormalities, etc. In addition, various software counters and timers are used.
[0029]
The constant voltage circuit 58 is connected to the battery 62 via a first relay contact of a power supply relay 61 having two relay contacts. In the power supply relay 61, one end of the relay coil is grounded, and the other end of the relay coil is connected to the drive circuit 59. A power line for supplying power from the battery 62 to each actuator is connected to the second relay contact of the power relay 61.
[0030]
In addition, one end of an ignition switch 63 is connected to the battery 62, and the other end of the ignition switch 63 is connected to an input port of the I / O interface 57. The constant voltage circuit 58 is directly connected to the battery 62. When the ignition switch 63 is detected to be ON and the contact of the power relay 61 is closed, the constant voltage circuit 58 supplies power to each part in the ECU 50, while the ignition switch 63 is turned on. Regardless of whether 63 is ON or OFF, the backup RAM 54 is always supplied with backup power.
[0031]
Further, an idle switch 35b, a knock sensor 37, a cam angle sensor 40, an air conditioner switch 44, a vehicle speed sensor 45, and the like are connected to an input port of the I / O interface 57, and further via an A / D converter 60, A throttle opening sensor 35a, an intake pipe pressure sensor 36, a cooling water temperature sensor 38, an O2 sensor 41, etc. are connected and a battery voltage VB is inputted and monitored. Further, the ISC valve 12, the injector 13, and the relay coil of the power supply relay 61 are connected to the output port of the I / O interface 57 via the drive circuit 59 and the igniter 16 is connected.
[0032]
On the other hand, the electronic control unit 70 (TCU 70) for transmission control is configured with a microcomputer as the center, like the ECU 50 for engine control. The TCU 70 receives signals from a throttle opening sensor 35 a and a coolant temperature sensor 38 shared with the ECU 50, a rotation speed signal from the primary pulley rotation speed sensor 42, and a rotation speed from the secondary pulley rotation speed sensor 43. A signal, a signal indicating an operation position of a not-shown select mechanism section from the inhibitor switch 46, a brake signal from the brake switch 47, and the like are input and connected to each other via the engine control ECU 50 and the SCI 55 so that data can be exchanged. . In the present embodiment, in addition to the normal drive range (D range), a sport range (Ds range) suitable for sports driving is provided as a shift position, which has a larger reduction ratio than the D range. .
[0033]
The transmission control TCU 70 processes detection signals from sensors and switches in accordance with a control program stored in an internal memory, and controls line pressure and pilot pressure to each mechanism of the torque converter 23 and transmission 24. In addition to controlling the engagement / slip / release of the lock-up clutch 22 and the shift control of the transmission 24 via a hydraulic control unit 24a in which various control valves are integrally formed. At the same time, the shift position, the control data of the lockup clutch 22 and the like are transmitted to the engine control ECU 50.
[0034]
On the other hand, in the engine control ECU 50, the CPU 51 processes the detection signals from the sensors and switches, the battery voltage and the like input via the I / O interface 57 in accordance with the control program stored in the ROM 52, The shift position, lockup clutch 22 control data, etc. are received from the transmission control TCU 70 via the SCI 55, and these received data, various data stored in the RAM 53, and various learning value data stored in the backup RAM 54. Based on the fixed data stored in the ROM 52, the fuel injection amount, the ignition timing, the duty ratio of the control drive signal for the ISC valve 12, etc. are calculated, and the fuel injection control including air-fuel ratio control, ignition timing control, idle rotation Engine control such as number control (ISC control) is performed.
[0035]
In this case, in the ISC control, in order to cope with an increase in engine load due to driving of various auxiliary machines, a large capacity ISC valve 12 is used to increase the amount of air in the bypass passage 11 to satisfy the required torque. However, with conventional control, in an AT vehicle equipped with a torque converter, the opening of the ISC valve 12 becomes too large during deceleration and the intake pipe negative pressure becomes insufficient. As a result, a phenomenon occurs in which the assist force of the brake booster 8 is relatively reduced during deceleration, the pedaling force of the brake pedal 9 is increased, and the effect of engine braking is reduced, and when the fuel cut during deceleration is restored. The problem arises that the torque shock increases.
[0036]
In order to cope with this, the ECU 50 sets a torque converter correction amount (AT vehicle torque converter correction amount ITC described later) in consideration of the engine load due to the stirring resistance of the torque converter 23 based on the input shaft speed of the transmission 24. The torque converter correction amount is used to correct the control amount for the ISC valve 12 in the direction of decreasing the opening degree of the ISC valve 12, thereby preventing the opening degree of the ISC valve 12 from becoming excessively large during deceleration. Ensure tube negative pressure.
[0037]
That is, the ECU 50 realizes functions as a torque converter correction amount setting unit and an opening degree control unit according to the present invention. Hereinafter, processing related to ISC control executed by the ECU 50 will be described with reference to the flowcharts shown in FIGS. 3 and 5.
[0038]
FIG. 3 is an ISC control routine that is executed every predetermined time (for example, every 10 msec) after system initialization. First, in step S101, a control amount QISC for the ISC valve 12 is set. The control amount QISC includes various well-known correction terms, for example, a water temperature correction amount ITW as a basic opening based on the engine temperature, a post-startup correction amount IAS for a first idle at the time of engine cold start, a target rotation speed and an actual rotation Feedback correction amount IFB based on the deviation from the number, learning correction amount ILRN by learning, load correction amount ILD for correcting the influence of load by auxiliary equipment such as an air conditioner, D for securing stoppage resistance and engine stall resistance The range correction amount IND and the idle-up correction amount IUP for coping with the increase in the required torque when the throttle valve 10 is fully closed are added terms, and the value obtained by adding these various correction terms increases the transmission input shaft speed. Subtract the AT car torque converter correction amount ITC that increases accordingly (QISC ← ITW + IAS + IFB + ILRN + ILD) IND + IUP-ITC). In step S102, the control amount QISC is set and the routine is exited. That is, as shown in FIG. 4, load correction and travel correction by various auxiliary machines are added as addition terms to the basic opening based on the engine temperature, and the AT vehicle is increased as the primary pulley rotation speed (transmission input shaft rotation speed) increases. By reducing the opening of the ISC valve 12 with the torque converter correction amount, the opening of the ISC valve 12 is prevented from becoming too large during deceleration, and the intake pipe negative pressure during deceleration is ensured.
[0039]
Next, the AT vehicle torque converter correction amount setting routine of FIG. 5 for setting the above AT vehicle torque converter correction amount ITC will be described. This routine is executed every predetermined time (for example, every 10 msec). First, in step S201, it is checked whether or not the current shift position is neutral based on the signal from the inhibitor switch 46.
[0040]
When the shift position is neutral, the routine proceeds from step S201 to step S202, the AT vehicle torque converter correction amount ITC is cleared to 0 (ITC ← 0), the routine is exited, and when the shift position is not neutral, step S201 is executed. From step S203, the air conditioner switch 44 checks whether the air conditioner is OFF. As a result, when the air conditioner is OFF, processing for setting the AT vehicle torque converter correction amount ITC corresponding to the air conditioner OFF (when the air conditioner is stopped) is performed after step S204. When the air conditioner is ON, the air conditioner ON ( A process for setting the AT vehicle torque converter correction amount ITC corresponding to the operation of the air conditioner is performed.
[0041]
That is, when the air conditioner is ON, in order to compensate for the engine load accompanying the operation of the air conditioner compressor, the opening amount of the ISC valve 12 is increased by the load correction amount ILD to increase the amount of bypass air, and the throttle valve 10 is fully closed including when the vehicle is running. A correction is made to increase the engine speed at the time. For this reason, if the AT vehicle torque converter correction amount ITC for reducing the bypass air amount for the purpose of securing the intake pipe negative pressure is set on the basis of the air conditioner OFF state, when the air conditioner is ON, the decrease in the engine speed is excessive. Thus, the engine load accompanying the air-conditioner compressor drive cannot be compensated, and the driving feeling may be deteriorated. Therefore, by setting the AT vehicle torque converter correction amount ITC separately for when the air conditioner is on and when the air conditioner is off, the intake pipe negative pressure is accurately secured regardless of whether the air conditioner is on or off, and engine stall is prevented. In addition, drivability is improved by eliminating the difference in driving feeling between when the air conditioner is on and when the air conditioner is off.
[0042]
First, the AT vehicle torque converter correction amount ITC setting process when the air conditioner is OFF after step S204 will be described. In step S204, the table TITCOF is referenced with interpolation calculation using the primary pulley rotation speed ZMBMWNPF as a parameter, and the AT vehicle torque converter correction amount ITC is set. In the table TITCOF, an appropriate correction amount obtained as a parameter using the primary pulley rotation speed ZMBMWNPF as a parameter when the air conditioner is turned off is stored as a table value ITCOF in advance by simulation or experiment. A correction amount ITC is set.
[0043]
That is, the engine load due to the stirring resistance of the torque converter 23 is the speed ratio of the input / output shaft rotational speed of the torque converter 23 (torque converter output shaft rotational speed / torque converter input) when the throttle valve 10 is fully closed during vehicle travel. It is inversely proportional to the shaft rotational speed = transmission input shaft rotational speed / engine rotational speed (see FIG. 6). Therefore, it is conceivable to set the AT vehicle torque converter correction amount ITC using the speed ratio as a parameter. However, when the torque converter 23 is locked up by the lock-up clutch 22, the speed ratio is uniquely 1.0, and the AT The vehicle torque converter correction amount ITC cannot be set appropriately. Therefore, the transmission input shaft rotation speed, that is, the primary pulley rotation speed ZMBMWNPF, which is the speed ratio parameter, is adopted as a parameter for setting the AT vehicle torque converter correction amount ITC, and the AT vehicle torque converter correction amount ITC is set appropriately.
[0044]
In this case, below the creep vehicle speed range (for example, ZMBMWNPF ≦ 400 rpm), ITC = 0 and no correction by the AT vehicle torque converter correction amount ITC is set. That is, the creep vehicle speed range or lower is when the vehicle is stopped or creeping, and the influence of the intake pipe negative pressure deficiency or intake pipe negative pressure deficiency when the throttle valve 10 is fully closed can be ignored. The vehicle torque converter correction amount ITC is not corrected.
[0045]
Further, in the region exceeding the creep vehicle speed, the AT vehicle torque converter correction amount ITC is gradually increased as the primary pulley rotational speed ZMBMWNPF increases, and the primary pulley rotational speed ZMBMWNPF is equal to or higher than a predetermined rotational speed (for example, 1600 rpm). In the region, the AT vehicle torque converter ITC is converged to a constant value. That is, in the region where the primary pulley rotation speed ZMBMWNPF is equal to or higher than the predetermined rotation speed, the engine rotation speed is relatively high, and therefore the intake pipe negative pressure does not change much even if the AT vehicle torque converter correction amount ITC is increased. Therefore, until the primary pulley rotation speed ZMBMWNPF reaches the predetermined rotation speed in the region exceeding the creep vehicle speed, the AT vehicle torque converter correction amount ITC is gradually increased, and the primary pulley rotation speed ZMBMWNPF is increased in the region in which the primary pulley rotation speed ZMBMWNPF is equal to or higher than the predetermined rotation speed. By converging the vehicle torque converter correction amount ITC to a constant value, the connection from the creep vehicle speed range is made smooth, the intake pipe negative pressure is ensured, and the AT vehicle torque converter correction amount ITC is prevented from changing suddenly, thereby improving the controllability and the driver. To improve the performance.
[0046]
Next, proceeding to step S205, the table TITCGDV is referred to with interpolation calculation using the vehicle speed ZMBSWNV as a parameter, and a vehicle speed correction upper limit regulation value ITCGDV for regulating the AT vehicle torque converter correction amount ITC according to the vehicle speed is set. That is, in the present embodiment, in addition to the normal D range, a Ds range having a larger reduction ratio is provided. In this Ds range, transmission input is compared with the normal D range at the same vehicle speed. The primary pulley rotation speed ZMBMWNPF, which is the shaft rotation speed, increases, and the AT vehicle torque converter correction amount ITC given as a negative term when setting the control amount QISC of the ISC valve 12 increases. Therefore, in the Ds range, the opening degree of the ISC valve 12 is relatively decreased as compared with the D range, and the engine speed decreases rapidly when decelerating by the brake, and engine stall may occur due to a decrease in the engine speed. Therefore, the AT vehicle torque converter correction amount ITC set with the primary pulley rotation speed ZMBMWNPF as a parameter is regulated by the vehicle speed correction upper limit regulation value ITCGDV set with the vehicle speed ZMBSWNV as a parameter, thereby preventing overcorrection in the Ds range. To prevent engine stalls. In this case, since the appropriate upper limit restriction value differs between when the air conditioner is ON and when the air conditioner is OFF, the table TITCGGDV includes an appropriate restriction obtained in advance by using a simulation or an experiment as a parameter for the vehicle speed ZMBSWNV corresponding to when the air conditioner is OFF A value is stored.
[0047]
In the subsequent step S206, the table TITCGDW is referred to with interpolation calculation using the cooling water temperature TW as a parameter, and a water temperature correction upper limit regulation value ITCGGDW for regulating the AT vehicle torque converter correction amount ITC according to the engine temperature is set. As is well known, the lower the engine temperature, that is, the engine cooling water temperature, the greater the engine friction due to the influence of the viscosity of the engine oil, etc. Accordingly, the lower the cooling water temperature, the lower the basic characteristic value. The water temperature correction amount ITW is set to increase, the opening of the ISC valve 12 is increased, the amount of bypass air is increased, and the decrease in the idling speed is compensated. Accordingly, the water temperature correction upper limit ITCGGDW based on the cooling water temperature is set in order to regulate the correction amount that is reduced by the AT vehicle torque converter correction amount ITC from the control amount QISC based on the water temperature correction amount ITW. Even in this case, since the appropriate upper limit restriction value is different between when the air conditioner is on and when the air conditioner is off, the table TITCGDW previously obtained the cooling water temperature TW as a parameter corresponding to when the air conditioner is turned off by simulation or experiment. Appropriate regulation values are stored.
[0048]
On the other hand, in the processing after step S207 when the air conditioner is ON, in step S207, the table TITCOFAC is referred to with interpolation calculation using the primary pulley rotation speed ZMBMWNPF as a parameter, and the AT vehicle torque converter correction amount ITC is set. In the table TITCOFAC, an appropriate correction amount obtained by using the primary pulley rotation speed ZMBMWNPF as a parameter corresponding to when the air conditioner is turned on in advance by simulation or experiment is stored as the table value ITCOFAC. It is a characteristic that takes into account the increase in engine load due to the air conditioner being turned on with respect to TITCOF.
[0049]
Next, the process proceeds to step S208, where the vehicle speed ZMBSWNV is used as a parameter and the table TITCGGDVA is referenced with interpolation calculation to set the vehicle speed correction upper limit regulation value ITCGGDV. The table TITCGGDVA stores in advance appropriate regulation values obtained by using the vehicle speed ZMBSWNV as a parameter corresponding to when the air conditioner is turned on by simulation or experiment, and the table TITCGGDV is turned on by turning the air conditioner on. It is a characteristic that takes into account the increase in engine load.
[0050]
In subsequent step S209, the table TITCGDWA is referred to with interpolation calculation using the cooling water temperature TW as a parameter, and the water temperature correction upper limit regulation value ITCGGDW is set. The table TITCGDWA stores in advance appropriate regulation values obtained by using the cooling water temperature TW as a parameter corresponding to when the air conditioner is turned on by simulation or experiment. In this case, in the present embodiment, the engine 1 is a naturally aspirated engine, and has a high engine stall resistance due to a difference in water temperature. Therefore, regardless of the difference in cooling water temperature TW and the difference in ON / OFF of the air conditioner, It is possible to set the correction upper limit ITCGGDW with a unique value. However, the characteristics of the engine differ depending on the engine type and the like. In particular, in the engine with a supercharger, the difference in the cooling water temperature TW and the difference in ON / OFF of the air conditioner affect the severeness when idling. , OFF, it is desirable to individually set the water temperature correction upper limit regulation value ITCGGDW.
[0051]
As described above, after setting the AT vehicle torque converter correction amount ITC, the vehicle speed correction upper limit restriction value ITCGGDV, and the water temperature correction upper limit restriction value ITCGGDW, the process proceeds from step S206 or step S209 to step S210 and the subsequent steps, and the vehicle speed correction upper limit restriction value ITCGGDV and the water temperature correction upper limit are set. The upper limit of the AT vehicle torque converter correction amount ITC is performed with the lower value of the regulation value ITCGGDW as the upper limit value. That is, in step S210, the vehicle speed correction upper limit regulation value ITCGDV is compared with the water temperature correction upper limit regulation value ITCGGDW. If ITCGGDV ≦ ITCGGDW, the vehicle speed correction upper limit regulation value ITCGDV is set as the upper limit value ITCGD in step S211 (ITCGD ← ITCGGDV). In step S213, if ITCGGDV> ITCGGDW, in step S212, the water temperature correction upper limit regulation value ITCGGDW is set to the upper limit value ITCGD (ITCGD ← ITCGGDW), and the process proceeds to step S213.
[0052]
In step S213, the AT vehicle torque converter correction amount ITC and the upper limit value ITCGD are compared. If ITC ≦ ITCGD, the routine is exited as it is. If ITC> ITCGD, in step S214, the AT vehicle torque converter correction amount ITC is limited to the upper limit value ITCGD to limit the upper limit (ITC ← ITCGD). Exit. In other words, by adopting the stricter one of the vehicle speed correction upper limit regulation value ITCGDV and the water temperature correction upper limit regulation value ITCGGDW, it is possible to reliably prevent overcorrection due to the AT vehicle torque converter correction amount ITC, and to eliminate the engine stall and To further improve the performance.
[0053]
FIG. 7 shows an example of the result of the reduction correction for the control amount of the ISC valve 12 by the AT vehicle torque converter correction amount ITC when the air conditioner is activated. By adopting the correction, as shown by the broken line, the intake pipe negative pressure in the low to medium vehicle speed range is optimized to obtain an appropriate engine braking feeling at the time of deceleration, and sufficient brake booster 8 assists during braking. You can gain power. Further, since the intake air amount of the engine during deceleration can be reduced to an appropriate value, the amount of torque generated when returning from the fuel cut can be suppressed, and the shock at the time of fuel recovery can be reduced.
[0054]
【The invention's effect】
As described above, according to the present invention, the opening of the idle control valve at the time of traveling can be optimized to ensure the intake pipe negative pressure at the time of deceleration, obtaining an appropriate engine brake feeling at the time of deceleration, Sufficient brake assist force can be obtained during braking. Further, since the intake air amount of the engine during deceleration can be reduced to an appropriate value, the amount of torque generated when returning from the fuel cut can be suppressed, and the shock at the time of fuel recovery can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of an engine and a drive system.
FIG. 2 is a circuit configuration diagram of an electronic control system.
FIG. 3 is a flowchart of an ISC control routine.
FIG. 4 is an explanatory diagram of a control amount for an ISC control valve.
FIG. 5 is a flowchart of an AT vehicle torque converter correction amount setting routine;
FIG. 6 is an explanatory diagram showing a change in torque converter stirring resistance
FIG. 7 is an explanatory diagram showing a change in intake pipe negative pressure due to ISC flow reduction.
[Explanation of symbols]
1 engine
12 Idle control valve
23 Torque converter
24 Transmission
50 Electronic control device (torque converter correction amount setting means, opening degree control means)
Control amount for QISC idle control valve
ITC AT car torque converter correction amount (torque converter correction amount)

Claims (6)

A control device for an engine idle control valve in which a transmission is connected to an output shaft of an engine via a torque converter,
Torque converter correction that sets the torque converter correction amount considering the engine load due to the stirring resistance of the torque converter separately according to the air conditioner operating and when the air conditioner is stopped based on the input shaft speed of the transmission A quantity setting means;
Opening degree control means for correcting the control amount for the idle control valve in a direction to decrease the opening degree of the idle control valve by using the torque converter correction amount, and controlling the opening degree of the idle control valve; A control device for an idle control valve of an engine. The torque converter correction amount setting means includes:
Below the creep vehicle speed range, the torque converter correction amount is a value corresponding to no correction,
In the region exceeding the creep vehicle speed, the torque converter correction amount is increased in accordance with the increase in the input shaft speed of the transmission,
2. The engine idle control valve control device according to claim 1, wherein the torque converter correction amount is converged to a constant value in a region where the input shaft rotational speed of the transmission is equal to or higher than a set rotational speed. The torque converter correction amount setting means includes:
3. The engine idle control valve control device according to claim 1, wherein the torque converter correction amount is subjected to upper limit regulation with a regulation value set based on a vehicle speed. The torque converter correction amount setting means includes:
3. The engine idle control valve control device according to claim 1, wherein the torque converter correction amount is subjected to upper limit regulation with a regulation value set based on engine temperature. The torque converter correction amount setting means includes:
The upper limit of the torque converter correction amount is regulated by a smaller regulation value of a regulation value set based on the vehicle speed and a regulation value set based on the engine temperature. The engine idle control valve control device described. The torque converter correction amount setting means includes:
Claim the regulation value to the upper limit restricting the upper Symbol torque converter correction amount, characterized in that separately set corresponding to the time of air conditioning Desho when donor operation and air Desho toner stops 1,2,3,4,5 The engine idle control valve control device according to any one of the above.

Images