JP2001159324A - Intake air quantity control device for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform control of an intake air quantity by desired responsiveness. SOLUTION: In this device for controlling an intake air quantity through control of the closing timing of an intake valve, a demand air quantity TLGQH0 to be controlled with low response is discriminated from a demand air quantity to be controlled with high response. After delay treatment on the demand air quantity TLGQH0 is executed, the demand quantity is added to a demand air quantity on which the delay treatment is not applied and which is controlled with high response to calculate a final demand air quantity FQH0ST, and a closing timing IVC of the intake valve is calculated according to the demand air quantity FQH0ST.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for controlling the amount of intake air by controlling the closing timing of an intake valve (variable valve) of an engine capable of arbitrarily variably controlling valve timing such as an electromagnetic drive type.

[0002]

2. Description of the Related Art In a conventional general engine, the intake air amount is controlled by the opening degree of a throttle valve. However, in recent years, an intake / exhaust valve of an electromagnetic drive type is provided, and the intake air amount is mainly controlled by controlling the closing timing of the intake valve. Has been proposed (see Japanese Patent Application Laid-Open No. 10-37727).

In this type of intake air amount control, when the throttle valve is not provided, the intake pressure is maintained at substantially the atmospheric pressure, and when the throttle valve is used together, the intake pressure corresponding to the throttle valve opening degree is increased. By controlling the volume of cylinder intake air according to the effective intake stroke determined by the closing timing of the valve, control can be performed to obtain a target air amount (required intake air amount) according to the required torque, As a result, fuel efficiency can be improved by reducing pumping loss.

[0004]

When controlling the amount of intake air using a normal throttle valve, an intake manifold or an intake collector is provided downstream of the throttle valve. The amount of air in the cylinder changes with a delay corresponding to the time constant of the intake system volume downstream of the valve. However, in the case of controlling the intake air amount of the engine by controlling the intake valve timing, the intake system Since there is no delay due to the volume, the intake air amount shows high responsiveness. For this reason, the response of the torque change due to the rapid accelerator operation is increased, and as a result, the power train system is vibrated, and there is a possibility that the drivability, the sound vibration and the like may be deteriorated.

[0005] The applicant of the present invention forcibly delays the responsiveness of the valve timing control of the intake valve, thereby preventing a sudden torque fluctuation and preventing a torque step when switching the intake air amount control. Proposed to eliminate.

However, when the delay processing is performed on the entire required air amount, the control is performed with a low response even for a control that requires a high response, and it is possible to bend by the intake valve. High-response control could not be used, which was irrational.

The present invention has been made in view of such a conventional problem, and provides an intake air amount control device for an engine in which the intake air amount is controlled in accordance with a request for responsiveness. The purpose is to:

[0008]

According to the present invention, there is provided an apparatus for controlling an intake air amount of an engine by controlling a closing timing of an intake valve capable of variably controlling a valve timing. The required air amount of the engine is classified according to the response of the control, and the closing timing of the intake valve is controlled based on the required air amount that has been subjected to a delay process according to the response.

According to a second aspect of the present invention, there is provided an apparatus for controlling an intake air amount of an engine by controlling a closing timing of an intake valve capable of variably controlling a valve timing as shown in FIG. Responsiveness classification means for classifying the required air amount of the engine according to the responsiveness of the control, and delay processing means for performing a delay process according to the responsiveness on the required air amount separated by the responsiveness classification means. And a closing timing control means for controlling the closing timing of the intake valve based on the required air amount subjected to the delay processing by the delay processing means.

According to the first and second aspects of the present invention, the required air amount of the engine is separated for each required air amount in accordance with the responsiveness of the control. A delay process is appropriately performed in response thereto, and the closing timing of the intake valve is controlled with respect to the required air amount after performing the delay process,
The intake air amount is controlled.

In this manner, the intake air amount can be controlled with the response characteristic corresponding to the response requirement, and the shift control and the traction control can be performed with high driving feeling while maintaining good driving feeling. Responsive control can be performed.

Further, the invention according to claim 3 is characterized in that the delay processing is performed only for a required air amount to be controlled with low response.

The delay processing is performed only for the low response control amount of the required air amount, and the delay processing is not performed for the high response control amount, so that the intake air amount control can be performed with response characteristics according to the response requirement. Can be performed. Although it is possible to perform a delay process smaller than the low response control for the high response control, the process is simplified by performing the delay process only for the low response control. .

Further, the invention according to claim 4 is characterized in that the required air amount to be controlled with low response includes a required air amount according to the accelerator operation amount by the driver.

According to the fourth aspect of the present invention, the response of torque change at the time of a sudden accelerator operation is reduced, so that the driving feeling equivalent to that of the throttle valve control can be obtained, and deterioration of noise and vibration can be prevented.

Further, the invention according to claim 5 is characterized in that the required air amount to be controlled with low response includes a correction amount for the cooling water temperature in the air amount for controlling the engine rotation speed at the time of idling. .

According to the fifth aspect of the present invention, since the correction for increasing the required air amount for increasing the rotation speed when the cooling water temperature is low does not require high-response control, a low-response control is not required. Classify as the required air volume to be controlled.

The invention according to claim 6 is characterized in that the required air amount to be controlled with a high response includes a correction amount at the time of shifting.

According to the sixth aspect of the invention, the torque down control for alleviating the shift shock at the time of shifting requires high-response control (a shift response cannot be exhibited if the response is low). The correction amount at the time of gear shifting is classified as a required air amount for controlling with high response.

The invention according to claim 7 is characterized in that the required air amount to be controlled with high response includes a traction control amount of the engine.

According to the seventh aspect of the present invention, the traction control of the engine requires high-responsive control for rapidly reducing the engine output. Therefore, the traction control is classified as the required air amount for controlling the responsiveness. I do.

In the invention according to claim 8, the volume flow ratio according to the required opening area of the idle rotation speed control is calculated as a value that is reduced at a high load with respect to a low load,
The required air amount is calculated using the volume flow ratio.

According to the eighth aspect of the present invention, as the total intake air amount increases as the load increases, the proportion of the air amount corresponding to the same opening area decreases. By calculating the volume flow ratio according to the above as a value that is reduced when the load is high and when the load is low, the required air amount can be calculated with high accuracy using the volume flow ratio.

According to a ninth aspect of the present invention, after calculating a volume flow ratio corresponding to the accelerator opening, a volume flow ratio corresponding to high response torque control is added, and the volume flow ratio is calculated from the added volume flow ratio. The opening area per unit flow rate is calculated by inverting the opening area per unit flow rate, and the opening area area per unit flow rate is calculated by adding the opening area area per unit flow rate for the low-response control of the idle rotation speed control. Further, a value obtained by subtracting a volume flow ratio for the total of the accelerator opening and the high response torque control from the volume flow ratio is calculated as a volume flow ratio for the low response control of the idling rotation speed control, and the volume flow ratio is calculated. The required air amount is calculated using a ratio.

According to the ninth aspect of the present invention, the volume flow ratio for the low response control of the idle speed control can be calculated with high accuracy. Can be calculated with high accuracy.

According to a tenth aspect of the present invention, the total volume flow rate for the low response control is obtained by adding the volume flow rate ratio corresponding to the accelerator opening and the volume flow rate ratio for the low response control of the idle speed control. A ratio is calculated, and the required air amount is calculated using the total volume flow ratio.

According to the tenth aspect, the required air amount can be calculated with high accuracy.

[0028]

Embodiments of the present invention will be described below. FIG. 2 is a system diagram of an engine including a variable valve control device according to an embodiment of the present invention.

The combustion chamber 3 defined by the piston 2 of each cylinder of the engine 1 is provided with an electromagnetically driven intake valve 5 and an exhaust valve 6 so as to surround the ignition plug 4. 7 is an intake passage, and 8 is an exhaust passage.

FIG. 3 shows the basic structure of an electromagnetic drive device for the intake valve 5 and the exhaust valve 6 (which constitutes a variable valve together with the intake and exhaust valves). A plate-shaped mover 2 is mounted on a valve shaft 21 of a valve body 20.
2 is attached, and the mover 22 is
It is urged by 3 and 24 to the neutral position. A valve opening electromagnetic coil 25 is disposed below the movable element 22, and a valve closing electromagnetic coil 26 is disposed above the movable element 22.

Before the engine 1 is started, the valve-opening electromagnetic coil 25 and the valve-closing electromagnetic coil 26 are alternately energized to resonate the mover 22, and when the amplitude becomes sufficiently large, one of the electromagnetic The mover 22 is suction-held by the coil.

Thereafter, when the valve is opened from the valve closed state, the energization of the upper valve closing electromagnetic coil 26 holding the movable element 22 is stopped, and then the movable element 2 is biased by the spring 23.
The valve body 20 is lifted and opened by energizing the valve opening electromagnetic coil 25 and attracting the mover 22 from a position sufficiently approaching the lower valve opening electromagnetic coil 25 to move the valve element 20 downward. Let it go.

On the other hand, when the valve is opened and closed, the mover 2
After stopping the energization of the lower valve-opening electromagnetic coil 25 that is adsorbing 2, the movable element 22 is moved upward by the urging force of the spring 24, and is sufficiently close to the upper valve-closing electromagnetic coil 26. From there, the valve closing electromagnetic coil 26 is energized,
By adsorbing the mover 22, the valve body 20 is seated on the seat and closed.

Returning to FIG. 2, an air flow meter 14 for detecting the amount of intake air and a throttle valve 15 for electronically controlling the opening degree are provided in the intake passage 7, and an electromagnetic type is provided at an intake port for each cylinder. Fuel injection valve 9 is provided.

Here, the operations of the intake valve 5, the exhaust valve 6, the throttle valve 15, the fuel injection valve 9 and the spark plug 4 are controlled by a control unit 10, which is synchronized with the engine rotation. A crank angle sensor 11 that outputs a crank angle signal and thereby detects an engine rotation speed, and an accelerator pedal sensor 1 that detects an accelerator opening (depression amount of an accelerator pedal)
2. Signals are input from a water temperature sensor 16 that detects the temperature of the cooling water of the engine.

Then, the intake air amount is controlled by controlling the closing timing of the intake valve 5 so as to obtain the target torque based on the operating conditions of the engine such as the accelerator opening and the engine speed.

Here, in controlling the amount of intake air,
The closing timing (IVC) of the intake valve 5 is controlled with respect to the required air amount that has been appropriately delayed according to the responsiveness. less than,
The IVC control according to the present invention will be described. FIG.
FIG. 5 is a control block diagram of a main routine and a subroutine, and FIGS. 6 and 7 are flowcharts of the same.

In FIG. 6, in step 1, the intake air amount corresponding to the air amount to be controlled with low response, specifically, the correction amount at the time of low water temperature, out of the required air amount in idle speed control (ISC). The required opening area A of the system is calculated.

In step 2, a required opening area B corresponding to a required air amount according to the accelerator opening is calculated as an air amount controlled with low response. In step 3, the required opening area A and the required opening area B are added as the required opening area corresponding to the total air amount controlled with the low response.

In step 4, the required opening area (A + B) corresponding to the added low response control is sequentially divided by the displacement (total stroke volume) and the engine speed Ne to obtain an opening area per unit volume flow rate. The corresponding value GADNVL is calculated.

In step 5, the volume flow ratio QH0STL for the low response control is calculated by GADNVL based on the preset characteristics shown in the figure. In step 6, a required opening area C corresponding to the total required air amount in the ISC is calculated.

In step 7, the required opening area (B + C) is calculated by adding the opening area B corresponding to the accelerator opening and the opening area C corresponding to the total required air amount of the ISC. In step 8, the required opening area (B + C) is sequentially divided by the displacement (total stroke volume) and the engine speed Ne to calculate a value TGADNV1 corresponding to the opening area per unit volume flow rate.

In step 9, the volume flow ratio TQH0ST1 corresponding to the TGADNV1 is calculated based on preset characteristics shown in the figure. In step 10, the required torque (negative torque) at the time of torque control requiring high response, for example, at the time of shifting or traction control, is converted into a volume flow ratio TQH0ST2 by multiplying by a coefficient.

In step 11, the total flow rate TQH0ST of the engine is calculated by adding the volume flow ratio TQH0ST1 calculated in step 9 and the volume flow ratio TQH0ST2 calculated in step 10.

In step 12, based on the total required air amount TQH0ST calculated in step 11 and the volume flow ratio QH0STL for low response control calculated in step 5, the volume flow ratio IHGQHR for high response control is calculated.
Is calculated as in the following equation.

IHGQHR = (TQH0ST-QH0S
TL) / TQH0ST In step 13, the volume flow ratio T for the total required air amount
QH0ST and volume flow ratio IHGQ for high response control
Based on the HR, a response delay process is performed on the low response control amount to calculate a required air amount by final intake valve closing timing (IVC) control, and an IVC corresponding to the required air amount is set. Perform IVC control. When the control using the throttle valve is also used (control for maintaining a predetermined intake pressure), the opening of the throttle valve is controlled based on the volume flow ratio TQH0ST for the total required air amount and the engine speed Ne. Is done.

FIG. 7 shows a flowchart of a subroutine in step 13. In step 21, I
The total required air amount TQH0SH of the VC control is calculated. This is because if the intake pressure is equal to the atmospheric pressure and the IVC control is performed without using the control by the throttle valve, the total required air amount TQH
0SH is the total required air amount TQH0S calculated in FIG.
T may be used, but when maintaining a predetermined intake pressure (negative pressure) together with throttle valve control, correction is made according to the intake pressure (when the negative pressure is large, the volume intake air amount Is required to be corrected by increasing the required air amount).

In step 22, the required air amount TLGQH0 for the low response control is calculated using the total required air amount TQH0SH for the IVC control and the volume flow ratio ratio IHGQHR for the high response control calculated in FIG. It is calculated by:

TLGQH0 = TQH0SH × (1−IHGQHR) In step 23, the required air amount TL for the low response control is calculated.
GQH0 is subjected to delay processing. For example, a weighted average calculation process is performed using the weight FLOAD referred to from the map based on the engine operating state (the rotation speed Ne and the load, etc.) according to the following equation to calculate the correction value FQH0LG.

FQH0LG = TLGQH0 × FLOAD
+ FQHOLD × (1−FLOAD) where FQHOLD is the previous calculated value of FQH0LG.

In step 24, the required air amount IHGQHB for the high response control is calculated by multiplying the total required air amount TQH0SH by the volume flow ratio ratio IHGQHR for the high response control as in the following equation.

IHGQHB = TQH0SH × IHGQHR In step 25, the required air amount IHGQHB for the high response control and the required air amount FQH0LG for the low response control that has been subjected to the delay processing are added as shown in the following equation. The total required air amount TQH0SH of the final IVC control is calculated.

TQH0SH = IHGQHB + FQH0LG In step 26, the target closing timing (IVC) of the intake valve according to the required air amount TQH0SH is set.

Thus, the electromagnetic drive device
The intake valve is controlled to close at the target closing timing.
With this configuration, the delay correction process is performed only for the required air amount for which the low response control corresponding to the accelerator opening and the ISC water temperature correction is preferable, and the ISC control and the high response torque control other than those described above are supported. Since the delay correction processing is not performed for the required air amount for which the high response control is preferable, the intake air amount control can be performed with the response characteristic according to the response request as shown in FIG. High-response control can be performed for speed change control, traction control, and the like, while ensuring excellent driving feeling.

In the above calculation, as shown in FIG. 9, the volume flow ratio TQH0 corresponding to the high response torque control is used.
ST2 is a constant value commensurate with the required torque irrespective of the change in load, whereas the volume flow ratio according to the required opening area of the ISC control decreases at high load compared to low load. That is, as the total intake air amount increases with an increase in load, the proportion of the air amount corresponding to the same opening area decreases.

Although the calculation becomes complicated, the volume flow ratio according to the required opening area of the ISC control can be calculated with higher accuracy in accordance with the change in the load. First, after calculating the volume flow ratio according to the accelerator opening, the volume flow ratio TQH0ST2 corresponding to the high response torque control is added, and the opening area per unit flow corresponding to the added volume flow ratio is inversely converted from the added volume flow ratio. The volume flow ratio is calculated with respect to the total opening area per unit flow obtained by adding the opening area per unit flow for the low response control of the ISC. A value obtained by subtracting the volume flow ratio for the total of the accelerator opening and the high response torque control from the volume flow ratio is calculated as the volume flow ratio for the low response control of the ISC. Then, the total volume flow ratio for the low response control is calculated by adding the volume flow ratio according to the accelerator opening and the volume flow ratio for the low response control of the ISC. The following is the same as in the above embodiment.

Although the amount of calculation increases as compared with the above-described embodiment, an appropriate delay process smaller than that of the low response control may be applied to the required air amount corresponding to the high response control. It is also possible to finely classify the required air amount according to the responsiveness, and to perform a delay process corresponding to each responsiveness.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration and functions of the present invention.

FIG. 2 is a system diagram of an engine including a variable valve control device according to an embodiment of the present invention.

FIG. 3 is a basic structural diagram of an electromagnetic drive device of an intake / exhaust valve.

FIG. 4 is a control block diagram of a main routine according to the embodiment.

FIG. 5 is a control block diagram of a subroutine according to the embodiment.

FIG. 6 is a flowchart of a main routine according to the embodiment.

FIG. 7 is a flowchart of a subroutine according to the embodiment.

FIG. 8 is a diagram showing response characteristics in the embodiment.

FIG. 9 is a diagram showing a ratio of each required air amount to a volume flow ratio under low load and high load in the embodiment.

[Explanation of symbols]

 Reference Signs List 1 engine 5 intake valve 9 fuel injection valve 10 control unit 11 crank angle sensor 12 accelerator pedal sensor 16 water temperature sensor

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) F02D 41/16 F02D 41/16 PF term (Reference) 3G092 AA11 AB02 BA01 BA03 DA07 DC01 EA16 FA03 GA04 GA12 GB09 HA01X HA06X HA11X HA13X HE01X HE06X 3G093 BA03 BA15 CA04 CB06 CB08 DA01 DA05 DA06 DA09 EA15 FB04 3G301 HA19 JA03 KA07 KA12 KB10 LA07 LC01 NE21 PE01A PE03A PE06A PE08A PE10A PF03A

Claims (10)

[Claims] An apparatus for controlling an intake air amount of an engine by controlling a closing timing of an intake valve capable of arbitrarily variably controlling a valve timing, wherein a required air amount of the engine is separated according to control responsiveness. An intake air amount control device for an engine, wherein the closing timing of the intake valve is controlled based on a required air amount subjected to a delay process according to the response. 2. An apparatus for controlling an intake air amount of an engine by controlling a closing timing of an intake valve capable of arbitrarily variably controlling a valve timing, wherein a required air amount of the engine is separated according to control responsiveness. Responsive classification means, delay processing means for performing delay processing according to responsiveness to the air amount separated by the responsive classification means, and the required air amount subjected to delay processing by the delay processing means And a closing timing control means for controlling a closing timing of the intake valve on the basis of the closing timing. 3. The intake air amount control device for an engine according to claim 1, wherein the delay processing is performed only for a required air amount to be controlled with low response. 4. The engine according to claim 1, wherein the required air amount to be controlled with low response includes a required air amount according to an accelerator operation amount by a driver. Intake air amount control device. 5. The required air amount to be controlled with low response includes a correction amount for the cooling water temperature in the air amount for controlling the engine rotation speed at the time of idling. An intake air amount control device for an engine according to any one of the preceding claims. 6. A demanded air amount to be controlled with high response includes a correction amount at the time of gear shifting.
An intake air amount control device for an engine according to any one of the above. 7. The engine intake air amount control apparatus according to claim 1, wherein the required air amount to be controlled with high response includes a traction control amount of the engine. 8. A volume flow ratio according to a required opening area of the idle rotation speed control is calculated as a value reduced at a high load compared to a low load, and the required air amount is calculated using the volume flow ratio. 8. The method according to claim 1, wherein the calculation is performed.
An intake air amount control device for an engine according to any one of the above. 9. A volume flow ratio corresponding to an accelerator opening is calculated, a volume flow ratio corresponding to high response torque control is added, and an opening area per unit flow corresponding to the added volume flow ratio is inverted. The volume flow ratio is calculated for the total opening area per unit flow obtained by adding the opening area per unit flow for the low response control of the idle rotation speed control, and further calculating the volume flow ratio from this volume flow ratio. A value obtained by subtracting the volume flow ratio for the total of the accelerator opening and the high response torque control is calculated as the volume flow ratio for the low response control of the idle speed control, and the required air flow rate is calculated using the volume flow ratio. The intake air amount control device for an engine according to any one of claims 1 to 8, which calculates 10. A total volume flow ratio for low response control is calculated by adding a volume flow ratio according to an accelerator opening and a volume flow ratio for low response control of idle speed control, and The engine intake air amount control device according to any one of claims 1 to 9, wherein the required air amount is calculated using a flow rate ratio.