JPH09100728A - Controller for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the exhaustion of NOx during acceleration. SOLUTION: During acceleration, the opening/closing timing of an air intake valve 9 is set to a propulsion angle side more than a normal opening/closing timing by a variable valve timing mechanism composed of a timing pulley assembly 23 and a step motor 24. Also, if an automatic transmission 44 is currently engaged in speed changing at this time, the ignition timing of an ignition plug 26 is controlled so as to reduce the output torque of an internal combustion engine 1. Thus, internal EGR is increased, the exhaustion of NOx is reduced and since the output torque of the internal combustion engine 1 is reduced, a shock caused by speed changing is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine having a variable valve timing mechanism capable of freely changing the opening / closing timing of an intake valve according to the operating state,
The present invention relates to a control device for an internal combustion engine, which is controlled in association with a shift state of a transmission connected to the internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, as a prior art document related to a control device for an internal combustion engine, one disclosed in Japanese Patent Laid-Open No. 4-303153 is known. This document discloses a technique in which a variable valve timing mechanism is used to retard the intake valve to reduce shift shock during acceleration.

[0003]

However, there is a problem that NOx (nitrogen oxide) emission increases during high load operation such as during sudden acceleration.

Therefore, the present invention has been made to solve such a problem, and provides a control device for an internal combustion engine capable of reducing NOx emission at the time of acceleration and reducing shift shock at that time. Is an issue.

[0005]

According to the control apparatus for an internal combustion engine of claim 1, the timing setting means advances the opening / closing timing of the intake valve during acceleration by using the variable valve timing mechanism than the normal opening / closing timing. Set on the side. In this way, during acceleration, the opening / closing timing of the intake valve is set to a more advanced side than usual and the internal EGR is increased, so NOx emissions can be reduced.

According to the control device for an internal combustion engine of claim 2,
The timing setting prohibiting means prohibits the opening / closing timing of the intake valve at the time of shifting of the transmission from being set to the retard side with respect to the opening / closing timing immediately before the start of shifting by using the variable valve timing mechanism. As described above, when shifting the transmission, it is prohibited to set the opening / closing timing of the intake valve to the retard side from immediately before the start of shifting, and the reduction of the internal EGR is suppressed, so that the emission of NOx can be reduced.

According to the control device for an internal combustion engine of claim 3,
The change using the variable valve timing mechanism of the opening and closing timing of the intake valve in order to reduce the output torque of the internal combustion engine at the time of gear shifting of the transmission by the timing change prohibiting means,
It is prohibited during sudden acceleration. As described above, the change of the opening / closing timing of the intake valve for reducing the output torque of the internal combustion engine using the variable valve timing mechanism in order to reduce the output torque of the internal combustion engine, that is, the change of the opening / closing timing of the intake valve to the retarded side is sudden. By prohibiting during acceleration, reduction of internal EGR can be suppressed and NOx emission can be reduced.

According to the control device for an internal combustion engine of claim 4,
The timing control means sets the opening / closing timing of the intake valve at the advance side using the variable valve timing mechanism at the time of acceleration and gear shift of the transmission, and the ignition means of the ignition means is set so that the output torque of the internal combustion engine is reduced. The ignition timing is controlled. As described above, by setting the opening / closing timing of the intake valve to the advanced side at the time of gear shifting of the transmission during acceleration, the internal EGR can be increased and NOx emission can be reduced, and the ignition timing control can be performed. The shift shock can be reduced by reducing the output torque of the internal combustion engine.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on specific embodiments.

FIG. 1 is a schematic diagram showing the overall configuration of an internal combustion engine control apparatus according to an embodiment of the present invention.

In FIG. 1, a piston 3 is vertically movable in a cylinder bore 2 of an internal combustion engine 1. The piston 3 is connected to a crankshaft (not shown) via a rod 4. These piston 3 and cylinder bore 2
A space surrounded by the cylinder head 5 and covering the upper part of the cylinder bore 2 is formed as a combustion chamber 6. An intake passage 7 as a mixture intake passage is provided on the upstream side of the combustion chamber 6, and an exhaust passage 8 as a combustion gas exhaust passage is provided on the downstream side of the combustion chamber 6 so as to communicate with each other. An intake valve 9 is attached to an intake port 7a of the intake passage 7 which opens to the combustion chamber 6, and an exhaust valve 10 is attached to an exhaust port 8a of the exhaust passage 8 which opens to the combustion chamber 6.

Outside air is introduced into the intake passage 7 through an air cleaner (not shown). An injector 11 is provided in the intake passage 7 near the intake port 7a, and a predetermined amount of fuel is injected into the intake passage 7 at a predetermined timing. As is well known, the injector 11 is supplied with fuel at a predetermined pressure from a fuel tank (not shown) by the operation of a fuel pump. Then, the mixture of fuel and intake air injected into the intake passage 7 is introduced into the combustion chamber 6 through the intake port 7a when the intake valve 9 is opened. Combustion and expansion of the air-fuel mixture introduced into the combustion chamber 6 gives a driving force to the internal combustion engine 1 via the piston 3 and the crankshaft. Further, the combustion gas burned in the combustion chamber 6 is discharged to the outside from the exhaust port 8a through the exhaust passage 8 when the exhaust valve 10 is opened.

In the middle of the intake passage 7, the accelerator pedal 1
A throttle valve 13 that is opened / closed in association with the stepping-in operation 2 is provided. By opening / closing the throttle valve 13, the amount of intake air to the intake passage 7 is adjusted. In the vicinity of the throttle valve 13, a throttle opening sensor 1 for detecting the throttle opening TA is provided.
4 are provided. A surge tank 15 that smoothes the pulsation of intake air is provided downstream of the throttle valve 13. An air flow meter 16 that detects the intake air amount Q is provided upstream of the throttle valve 13.

Next, the valve mechanism will be described.

As shown in FIG. 1, the intake valve 9 and the exhaust valve 10 have stems 9a and 10a extending upward, respectively.
The valve springs 17, 18 and the valve lifters 19, 20 are attached to the upper portions of the stems 9a, 10a, respectively. In each valve lifter 19 and 20,
The cams 21a and 22a are provided so as to engage with each other. These cams 21a and 22a are the cylinder head 5
Are formed on the intake-side camshaft 21 and the exhaust-side camshaft 22 which are supported by the respective cylinders. Then, the intake valve 9 and the exhaust valve 10
Is urged upward by the urging force of the valve springs 17 and 18 and in the direction of closing the intake port 7a and the exhaust port 8a. In this biased state, each stem 9
The upper ends of a and 10a are always in contact with the cams 21a and 22a via the valve lifters 19 and 20.

In this embodiment, the timing pulley assembly 23 forming the variable valve timing mechanism and the step motor 2 are provided at the tip of the intake-side camshaft 21.
4 are provided. On the other hand, only the timing pulley 25 is provided at the tip of the camshaft 22 on the exhaust side. These timing pulley assembly 2
3 and the timing pulley 25 are connected to the crankshaft via a timing belt (not shown).

Therefore, when the internal combustion engine 1 is operating, power is transmitted from the crankshaft to the timing pulley assembly 23 and the timing pulley 25 via the timing belt, the camshafts 21 and 22 are rotated, and the profiles of the cams 21a and 22a are changed. Accordingly, the valve lifters 19 and 20 are pressed against the urging forces of the valve springs 17 and 18, so that the intake valve 9 and the exhaust valve 10 move downward and the intake port 7a and the exhaust port 8a are opened. As is well known, the basic opening / closing timing of the intake valve 9 and the exhaust valve 10 is the rotation of the crankshaft (two rotations), that is, the 4th of the piston 3.
One process (intake stroke, compression stroke, expansion stroke, exhaust stroke)
It is set in advance corresponding to the vertical movement associated with. here,
The intake port 7 is moved by the downward movement of the piston 3 during the intake stroke.
When a (the intake valve 9) is opened, the air-fuel mixture is sucked into the combustion chamber 6. Further, combustion gas is discharged from the combustion chamber 6 to the exhaust passage 8 when the exhaust port 8a (exhaust valve 10) is opened by the upward movement of the piston 3 accompanying the exhaust stroke.

The timing pulley assembly 23 on the intake side is drive-controlled so as to change the basic opening / closing timing of the intake valve 9 according to the operating state at that time, and the camshaft 21 and eventually the valve lifter of each cam 21a. The rotation phase with respect to 19 is changed appropriately. That is, the intake side timing pulley assembly 23 is drive-controlled to change the intake timing of the air-fuel mixture into the combustion chamber 6.

In order to ignite the air-fuel mixture introduced into the combustion chamber 6, the spark plug 2 is attached to the cylinder head 5 at the center of the cylinder.
6 is fixed, and this discharge part 26a is arranged in the combustion chamber 6. This spark plug 26 is the distributor 2
It is driven based on the ignition signal distributed in 7. The high voltage output from the igniter 28 is distributed from the distributor 27 to the spark plug 26 in synchronization with the crank angle of the internal combustion engine 1. Also, the distributor 2
Reference numeral 7 denotes a rotor 2 which is rotated in association with the rotation of the internal combustion engine 1.
7a is provided, and a rotation angle sensor 29 that detects the engine speed NE from the rotation of the rotor 27a is provided.
In addition, the internal combustion engine 1 is provided with a water temperature sensor 30 that detects the cooling water temperature THW.

Next, the structure of the variable valve timing mechanism will be described in detail with reference to FIG.

In FIG. 2, the intake-side camshaft 21 that drives the intake valve 9 has a cam journal 21b.
Is rotatably supported by the cylinder head 5. A timing pulley assembly 23 is provided at the tip of the cam shaft 21. The timing pulley assembly 23 includes a pulley body 32 having a plurality of outer teeth 31 on the outer circumference, an inner cap 33 and a cylindrical gear 34 assembled to the pulley body 32. That is, the pulley body 32 has a boss 32a and a circumferential wall 32b near the center thereof, and a circumferential groove 32c is provided between the boss 32a and the circumferential wall 32b. Helical teeth 32d are formed on the inner circumference of the circumferential wall 32b. The pulley body 32 is mounted on the cam shaft 21 by its boss 32a so as to be relatively rotatable.

On the other hand, the inner cap 33 has a large cylinder portion 33a and a small cylinder portion 33b extending to the opposite side, and the large cylinder portion 33a.
Helical teeth 33c are formed on the outer periphery of the. The large cap portion 33a of the inner cap 33 is fitted so as to cover the boss 32a, and is assembled so as to be rotatable relative to the pulley body 32. Further, the inner cap 33 is attached to the tip of the cam shaft 21 by the bolt 35 and the knock pin
It is integrally and rotatably fixed by 6. Furthermore,
The cylindrical gear 34 is formed of an outer peripheral wall 34a and an inner peripheral wall 34b, and a hole 34c is formed in the bottom wall thereof. Helical teeth 34d and 34e are formed on the inner and outer circumferences of the inner peripheral wall 34b, and a circumferential groove 34f is formed between the outer peripheral wall 34a and the inner peripheral wall 34b. The inner peripheral wall 34b and the circumferential groove 34f of the cylindrical gear 34 are assembled to the circumferential wall 32b and the circumferential groove 32c of the pulley main body 32 in an uneven relationship.

In this assembled state, each helical tooth 3
2d, 33c, 34d, and 34e are meshed with each other, and due to the meshing relationship, the cylindrical gear 34 is rotatable relative to the cam shaft 21 by moving in the axial direction. Further, the timing pulley assembly 23 is connected to the crankshaft via a timing belt (not shown) that is attached to the outer teeth 31 of the pulley body 32.

Therefore, the pulley main body 32 connected to the cylindrical gear 34 and the inner cap 33 are integrally rotated by the drive transmission from the crankshaft to the timing pulley assembly 23, and further, the inner cap 33 is further rotated by the bolt 35 and the knock pin 36. The cam shaft 21 connected to the cap 33 is integrally driven to rotate. The step motor 24 is attached to the internal combustion engine 1 by a bracket (not shown). The step motor 24 has a cylindrical gear 34.
Is moved in the axial direction, and a worm gear 37 having a cylindrical shape and teeth 37a on the outer periphery is attached to the output shaft thereof.
The worm gear 37 is a small cylinder portion 33b of the inner cap 33.
It is fitted so as to be rotatable relative to, and is arranged so as to penetrate through the hole 34c of the cylindrical gear 34. On the other hand, around the hole 34c of the cylindrical gear 34, a ring gear 38 having teeth 38a on its inner circumference is relatively rotatably assembled by a ball bearing 39. The ring gear 38 is meshed with the outer circumference of the worm gear 37, and due to the meshing relationship, the ring gear 38 is movable in the axial direction by rotation.

Therefore, when the timing pulley assembly 23 and the cam shaft 21 are integrally rotated, the step motor 24 is driven and the worm gear 3 is driven.
When 7 rotates by a predetermined amount, the ring gear 38 moves in the axial direction while rotating on the worm gear 37. Along with this, the cylindrical gear 34 is moved in the same axial direction, relative rotation occurs between the pulley body 32 and the cam shaft 21, and the cam shaft 21 is twisted. As described above, in the variable valve timing mechanism of the present embodiment, the position of the cylindrical gear 34 in the axial direction is changed by driving and controlling the step motor 24, and as a result, the camshaft 21 is twisted. . Then, by imparting a twist to the camshaft 21, the intake valve 9
The opening / closing timing of is changed from the basic opening / closing timing.

The oil passage 4 is provided inside the camshaft 21.
0 and 41 are formed, and lubricating oil is supplied to the inside of the timing pulley assembly 23 through the oil passages 40 and 41. As shown in FIG. 1, the throttle opening sensor 14, the air flow meter 16, the rotation angle sensor 29, the water temperature sensor 30, and the like are connected to an internal combustion engine ECU (Electronic Controller).
control unit (electronic control unit) 42 is electrically connected to the input side. The injector 11, the igniter 28, the step motor 24, etc. are electrically connected to the output side of the internal combustion engine ECU 42. The internal combustion engine ECU 42 includes a CPU as a well-known central processing unit,
It is configured as a logical operation circuit including a ROM storing a control program and a RAM storing various data.

In such an electrical structure, the internal combustion engine ECU 42 includes the air flow meter 16 and the sensors 1.
The detected values of 4, 29, 30 and the like are read, and the step motor 24 is appropriately drive-controlled so as to control the opening / closing timing of the intake valve 9 in accordance with the operating state of the internal combustion engine 1. Also,
The internal combustion engine ECU 42 appropriately controls the drive of the injector 11 so as to control the fuel injection amount into the intake passage 7 and the timing thereof according to the operating state of the internal combustion engine 1. Similarly, the internal combustion engine ECU 42 controls the ignition timing of the ignition plug 26 according to the operating state of the internal combustion engine 1.
The igniter 28 is controlled appropriately.

As described above, the internal combustion engine ECU 42 executes valve timing control, fuel injection control and ignition timing control. In addition to this, in the present embodiment, ECT (Electronic Controlled Transmission) is performed. Machine) ECU 43 is provided. That is, the internal combustion engine 1 is connected to an overdrive four-speed automatic transmission 44 with a direct coupling clutch for switching the speed change state. Then, the ECT ECU 43 executes the direct coupling clutch control and the shift control in the automatic transmission 44. Therefore, a shift position sensor 45, which is provided in the gear shift mechanism of the automatic transmission 44 and detects the shift position Psift, is electrically connected to the input side of the ECT ECU 43. An actuator (not shown) incorporated in the automatic transmission 44 is electrically connected to the output side of the ECT ECU 43. Further, data signals are exchanged between the ECT ECU 43 and the internal combustion engine ECU 42. Then, the ECT ECU 43 is the internal combustion engine ECU 4
2 to the air flow meter 16 and each sensor 14, 29,
When you read the data signal such as the detection value of 30 or the calculation result,
The automatic transmission 44 is appropriately controlled according to the shifting conditions at each time.

The ECU 43 for the ECT, like the ECU 42 for the internal combustion engine, has a C functioning as a well-known central processing unit.
It is configured as a logical operation circuit including a PU, a ROM storing a control program, and a RAM storing various data.

Next, a control procedure of the internal combustion engine 1 with a variable valve timing mechanism configured as described above will be described. In this embodiment, the ignition timing control of the spark plug 26 and the valve timing control of the intake valve 9 are executed in order to reduce the shift shock of the automatic transmission 44.

First, the shift determination and the ignition timing retard amount SAsift calculation executed by the ECT ECU 43 used in the internal combustion engine control apparatus of the present embodiment will be described. FIG. 3 is a flow chart showing a processing procedure therefor, and this routine is executed at regular intervals of 180 ° CA in crank angle.

First, in step S101, the throttle opening TA is read based on the detection value of the throttle opening sensor 14. Next, the process proceeds to step S102, and it is determined whether or not the throttle valve 13 is in the idle state in which it is fully closed based on the throttle opening TA read in step S101. When the determination condition of step S102 is satisfied and the vehicle is in the idle state, the process proceeds to step S103,
The valve timing advance amount θsift for controlling the valve timing of the intake valve 9 is set to “0”, and this routine ends.

On the other hand, when the determination condition of step S102 is not satisfied and the vehicle is not in the idle state but in the traveling state, the process proceeds to step S104, the shift position Psift is read based on the detection value of the shift position sensor 45, and the value is read this time. The current shift position PsiftN in the control cycle is. Next, the process proceeds to step S105, and the current shift position PsiftN
It is determined whether and the previous shift position PsiftO are equal.
When the determination condition of step S105 is satisfied, the automatic transmission 44 has not been shifted, so this routine ends. On the other hand, when the determination condition of step S105 is not satisfied, the automatic transmission 44 is being shifted, so the routine proceeds to step S106, where the current shift position PsiftN is larger than the previous shift position PsiftO, that is, whether the shift is up. To be judged.

When the condition for determination in step S106 is satisfied and upshift is being performed, the engine speed NE changes from a high state to a low state, and as a result, the output torque of the internal combustion engine 1 decreases greatly, so that the automatic shift It is necessary to increase the correction amount for reducing the shift shock in the machine 44, and the process proceeds to step S107. In step S107, the ignition timing retard amount SAsiftα is calculated based on the throttle opening TA read in step S101. This ignition timing retard amount SAsiftα [°] is calculated based on a table preset with the throttle opening TA [%] as a parameter, as shown in FIG. 4. In the table of FIG. 4, the ignition timing retard amount SAsiftα is set only in a region where the throttle opening TA is large, that is, a region where the load of the internal combustion engine 1 is large.

On the other hand, when the determination condition of step S106 is not satisfied and the engine is downshifting, the engine speed NE changes from a low state to a high state, so that the output torque change of the internal combustion engine 1 is small and the automatic transmission 44 Since the correction amount for reducing the shift shock in step S3 can be small, the process proceeds to step S108. In step S108, the throttle opening TA read in step S101
Based on the above, the ignition timing retard amount SAsiftβ is calculated. The ignition timing retard amount SAsift β [°] is calculated based on a table preset with the throttle opening TA [%] as a parameter, as shown in FIG. FIG.
In the table of FIG. 4, only the region where the throttle opening TA is large, that is, the region where the load of the internal combustion engine 1 is large,
The ignition timing retarding amount SAsiftβ is set to be smaller than the ignition timing retarding amount SAsiftα in the table.

Step S107 or step S108
After the processing of step S109, the current shift position PsiftN is set to the previous shift position PsiftO, and this routine ends. In this way, the determination of the shift position Psift of the automatic transmission 44 and the calculation of the ignition timing retardation amount SAsift according to the load of the internal combustion engine 1 are executed.

Next, the ignition timing control of the spark plug 26 executed by the internal combustion engine ECU 42 used in the internal combustion engine control apparatus of the present embodiment will be described. FIG.
Is a flowchart showing a processing procedure therefor,
This routine is executed at regular intervals every 180 ° CA in crank angle.

First, in step S201, the intake air amount QA, the engine speed NE, and the cooling water temperature THW are read based on the detection values of the air flow meter 16, the rotation angle sensor 29, and the water temperature sensor 30, respectively. Next, step S20
2, the intake air amount QA read in step S201 is divided by the engine speed NE to calculate the unit intake air amount Ga which is the intake air amount per one rotation. Next, the process proceeds to step S203, and the basic ignition timing SABase is calculated from the engine speed NE read in step S201 and the unit intake air amount Ga calculated in step S202. This basic ignition timing SABase [°] is calculated based on a table preset with the engine speed NE [rpm] and the unit intake air amount Ga as parameters, as shown in FIG. 7.

Next, in step S204, the ignition timing water temperature correction amount SATWH is calculated from the cooling water temperature THW read in step S201. This ignition timing water temperature correction amount SATWH [°] is, as shown in FIG. 8, the cooling water temperature TH.
It is calculated based on a preset table using W [° C.] as a parameter. Next, the routine proceeds to step S205, where the ignition timing retard amount SAsift calculated by the ECT ECU 43 is read. The ignition timing retard amount SAsift is either the ignition timing retard amount SAsiftα or the ignition timing retard amount SAsiftβ.

Next, in step S206, the basic ignition timing SABase calculated in step S203 and the ignition timing water temperature correction amount SATHW calculated in step S204 are added, and the ignition timing retard amount SAsift is further subtracted. The result is calculated as the ignition timing SA. Next, step S
Then, the routine proceeds to 207, where the ignition timing SA calculated in step S206 is output, the spark plug 26 is controlled, and this routine is ended. In this way, when the ignition timing control of the spark plug 26 is executed and the automatic transmission 44 is shifted,
The ignition timing SA is retarded by the ignition timing retard amount SAsift.

Next, the valve timing control of the intake valve 9 executed by the internal combustion engine ECU 42 used in the internal combustion engine control apparatus of the present embodiment will be described. FIG. 9 is a flowchart showing a processing procedure therefor, and this routine is executed at a regular interrupt every 180 ° CA of the crank angle.

First, in step S301, the throttle opening TA and the engine speed NE are read based on the detection values of the throttle opening sensor 14 and the rotation angle sensor 29, respectively. Next, the process proceeds to step S302, and step S3
The throttle opening TA and engine speed N read in 01
The basic valve timing amount θBase is calculated from E. As shown in FIG. 10, the basic valve timing amount θBase [°] is equal to the throttle opening TA [%] and the engine speed N.
It is calculated based on a preset table using E [rpm] as a parameter.

Next, the routine proceeds to step S303, where the previous smoothed value TASM and the present throttle opening TA are smoothed by the following equation (1), and the current smoothed value TASM is calculated.

[0044]

## EQU1 ## TASM = (31 * TASM + TA) / 32 (1) Next, the process proceeds to step S304, and the throttle opening TA
The difference between the smoothed value TASM and the smoothed value TASM is multiplied by a constant K to calculate the valve timing advance amount θAcc by the following equation (2).

[0045]

[Equation 2] θAcc = K * (TA-TASM) (2) This valve timing advance amount θAcc [°] is the throttle opening TA as shown in the time chart in FIG.
[%] Is smoothed by the smoothed value TASM [%], and a smooth transition occurs.

Next, the routine proceeds to step S305, where the basic valve timing amount θBase calculated at step S302.
Is added to the valve timing advance amount θAcc calculated in step S304, and the valve timing θ is calculated by the following equation (3).

[0047]

## EQU3 ## θ = θBase + θAcc (3) Next, the process proceeds to step S306 and the ECT ECU 43
It is determined by the signal from the automatic transmission 44 during the shift (during the shift period). When the determination condition of step S306 is satisfied, the process proceeds to step S307,
This valve timing θ is the previous valve timing θ
It is determined whether it is older than or equal to old. When the determination condition of step S307 is not satisfied, the process proceeds to step S308, and the previous valve timing θold is set as the valve timing θ.

Since the determination condition of step S306 is not satisfied,
When the automatic transmission 44 is not shifting, or when the determination condition of step S307 is satisfied and the current valve timing θ is equal to or greater than the previous valve timing θold, or after the processing of step S308, step S30 is performed.
9, the variable valve timing mechanism is driven by outputting the valve timing θ, that is, the step motor 24 is controlled, and this routine is ended.

As described above, the valve timing control of the intake valve 9 is executed. Even when the shift position Psift of the automatic transmission 44 changes, the valve timing control is executed so as to advance the valve timing θ by the valve timing advance amount θAcc during acceleration.

As described above, during acceleration, the internal EGR of the internal combustion engine 1 increases and NOx can be reduced by controlling the valve timing to the advance side. Even when accelerating and shifting the automatic transmission, the valve timing is set to be smaller than that during steady operation by setting the smoothing rate of the throttle opening smoothing value TASM and the constant K in the present embodiment to appropriate values. It can be set to the advance side. Further, since the automatic transmission 44 executes the ignition retard when shifting, it is possible to reduce the shift shock and further reduce NOx.

As described above, the control device for an internal combustion engine of the present embodiment has an intake valve 9 for opening and closing the intake passage 7 leading to the combustion chamber 6 of the internal combustion engine 1, and a timing at which the opening / closing timing of the intake valve 9 can be freely changed. Achieved by a variable valve timing mechanism including a pulley assembly 23 and a step motor 24, and an internal combustion engine ECU 42 that sets the opening / closing timing of the intake valve 9 during acceleration to a more advanced side than the normal opening / closing timing by the variable valve timing mechanism. And a timing setting means.

Therefore, in the internal combustion engine ECU 42 as the timing setting means, the opening / closing timing of the intake valve 9 at the time of acceleration is variable. The timing pulley assembly 23 and the step motor 2 as the variable valve timing mechanism.
4 is used to set the advance angle side of the normal opening / closing timing. As a result, during acceleration, the opening / closing timing of the intake valve 9 is set to a more advanced side than usual and the internal EGR is increased, so that NOx emissions are reduced.

Further, the control device for an internal combustion engine according to the present embodiment is provided with an intake valve 9 for opening and closing an intake passage 7 leading to a combustion chamber 6 of the internal combustion engine 1, and an automatic valve which is connected to the internal combustion engine 1 and switches its speed change state. Timing pulley assembly 2 that can freely change the opening / closing timing of the transmission 44 and the intake valve 9
3 and the stepping motor 24, and the opening / closing timing of the intake valve 9 at the time of shifting of the automatic transmission 44 is set to a retard side with respect to the opening / closing timing immediately before the start of shifting by the variable valve timing mechanism. The timing setting prohibition means achieved by the prohibiting internal combustion engine ECU 42 is provided.

Therefore, in the internal combustion engine ECU 42 as the timing setting prohibiting means, the opening / closing timing of the intake valve 9 at the time of shifting the automatic transmission 44 is variable. The timing pulley assembly 23 as the variable valve timing mechanism.
Also, it is prohibited to use the step motor 24 to set the delay side of the opening / closing timing immediately before the start of gear shifting.
As a result, when the automatic transmission 44 shifts, the intake valve 9
It is prohibited to set the opening / closing timing of the valve to the retard side from immediately before the start of the shift, and the decrease of the internal EGR is suppressed, so that the emission of NOx is reduced. The control device for an internal combustion engine according to the present embodiment includes an intake valve 9 that opens and closes an intake passage 7 that communicates with a combustion chamber 6 of the internal combustion engine 1, and an automatic transmission 44 that is connected to the internal combustion engine 1 and switches its shift state. And a variable valve timing mechanism including a timing pulley assembly 23 and a step motor 24 capable of changing the opening / closing timing of the intake valve 9, and the intake valve 9 for reducing the output torque of the internal combustion engine 1 during a shift of the automatic transmission 44. E for internal combustion engine for prohibiting change of opening / closing timing of the engine by the variable valve timing mechanism during sudden acceleration
The timing change prohibition means achieved by the CU 42 is provided.

Therefore, the timing pulley as a variable valve timing mechanism of the opening / closing timing of the intake valve 9 for reducing the output torque of the internal combustion engine 1 at the time of shifting the automatic transmission 44 by the internal combustion engine ECU 42 as the timing change prohibiting means. Changes using the assembly 23 and the step motor 24 are prohibited during sudden acceleration.
As a result, the opening / closing timing of the intake valve 9 for reducing the output torque of the internal combustion engine 1 when the automatic transmission 44 shifts is changed using the variable valve timing mechanism, that is, the opening / closing timing of the intake valve 9 is retarded. By prohibiting the change of NOx at the time of sudden acceleration, the decrease of the internal EGR is suppressed, so that the emission of NOx is decreased.

Further, the control device for an internal combustion engine according to the present embodiment is provided with an intake valve 9 for opening and closing an intake passage 7 leading to the combustion chamber 6 of the internal combustion engine 1, and an air-fuel mixture sucked into the combustion chamber 6 through the intake passage 7. An ignition means including an ignition plug 26 for igniting the vehicle, an automatic transmission 44 that is connected to the internal combustion engine 1 to switch the speed change state, a timing pulley assembly 23 and a step motor 24 that can change the opening / closing timing of the intake valve 9. The variable valve timing mechanism and the opening / closing timing of the intake valve 9 during shifting of the automatic transmission 44 during acceleration are set to the advanced side by the variable valve timing mechanism, and the output torque of the internal combustion engine 1 is reduced. And a timing control means that is achieved by the internal combustion engine ECU 42 that controls the ignition timing of the ignition means. It is.

Accordingly, the timing of opening and closing the intake valve 9 at the time of acceleration by the internal combustion engine ECU 42 as the timing control means and at the time of shifting of the automatic transmission 44 uses the timing pulley assembly 23 and the step motor 24 as the variable valve timing mechanism. The ignition timing of the spark plug 26 is controlled so that the output torque of the internal combustion engine 1 is reduced. As a result, the opening / closing timing of the intake valve 9 is set to the advance side when the automatic transmission 44 shifts during acceleration.
In addition to increasing the internal EGR and reducing NOx emissions, the output shock of the internal combustion engine 1 is reduced by controlling the ignition timing, so that shift shock is reduced.

In the above embodiment, the internal combustion engine 1 connected to the automatic transmission 44 is embodied. However, the present invention is not limited to this and is not limited to this.
It may be embodied in an internal combustion engine connected to a manual transmission.

In the above embodiment, the ignition plug is used as the ignition means, but the present invention is not limited to this.

In the above embodiment, the valve timing advance amount θAcc, the ignition timing retard amount SAsift, etc. are calculated based on the throttle opening TA which is the detected value of the throttle opening sensor 14. If you do
The present invention is not limited to this, and an accelerator opening sensor is provided instead of the throttle opening sensor 14, and the valve timing advance amount θAcc, the ignition timing retard amount SAsift, etc. are determined based on the detected accelerator opening. It may be calculated.

Further, in the above-mentioned embodiment, the present invention is carried out only during the rapid acceleration in which the NOx emission amount becomes large. However, the present invention is not limited to this, and during the normal acceleration, The valve timing may be retarded at the time of gear shifting of the transmission to reduce gear shift shock. Also, the variable valve timing mechanism may be embodied as a hydraulic drive type or an ON / OFF type.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an overall configuration of a control device for an internal combustion engine according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a variable valve timing mechanism in a control device for an internal combustion engine according to an embodiment of the present invention.

FIG. 3 is a flowchart showing a processing procedure of gear shift determination and ignition timing retard angle amount calculation in the ECT ECU used in the internal combustion engine control apparatus according to the embodiment of the present invention.

FIG. 4 is a table for obtaining an ignition timing retard amount SAsiftα with the throttle opening TA in FIG. 3 as a parameter.

5 is a table for obtaining an ignition timing retard amount SAsiftβ using the throttle opening TA as a parameter in FIG. 3;

FIG. 6 is a flowchart showing a processing procedure of ignition timing control in the internal combustion engine ECU used in the internal combustion engine control apparatus according to the embodiment of the present invention.

FIG. 7 is a table for obtaining a basic ignition timing SABase using the engine speed NE and the unit intake air amount Ga in FIG. 6 as parameters.

FIG. 8 is a table for obtaining an ignition timing water temperature correction amount SATWW using the cooling water temperature THW in FIG. 6 as a parameter.

FIG. 9 is a flowchart showing a processing procedure of valve timing control in the internal combustion engine ECU used in the internal combustion engine control apparatus according to the embodiment of the present invention.

FIG. 10 is a table for obtaining the basic valve timing amount θBase using the throttle opening TA and the engine speed NE in FIG. 9 as parameters.

FIG. 11 is a time chart showing a transition of the valve timing advance amount θAcc in FIG. 9.

[Explanation of symbols]

 1 Internal Combustion Engine 6 Combustion Chamber 7 Intake Passage 9 Intake Valve 23 Timing Pulley Assembly 24 Step Motor 26 Spark Plug 42 Internal Combustion Engine ECU (Electronic Control Unit) 43 ECT ECU

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location F02D 41/04 320 F02D 41/04 320 43/00 ZAB 43/00 ZAB 301 301B 301Z 45/00 ZAB 45/00 ZAB 312 312E 312M F02M 25/07 ZAB F02M 25/07 ZABA F02P 5/15 ZAB F02P 5/15 ZABF

Claims (4)

[Claims] 1. An intake valve that opens and closes an intake passage that communicates with a combustion chamber of an internal combustion engine, a variable valve timing mechanism that can change the opening and closing timing of the intake valve, and an opening and closing timing of the intake valve during acceleration. A control device for an internal combustion engine, comprising: a timing setting unit that sets a timing mechanism to an advance side with respect to a normal opening / closing timing. 2. An intake valve that opens and closes an intake passage that communicates with a combustion chamber of an internal combustion engine, a transmission that is connected to the internal combustion engine and switches its shift state, and a variable valve timing that is capable of changing the opening and closing timing of the intake valve. A mechanism and a timing setting prohibiting means for prohibiting the variable valve timing mechanism from setting the opening / closing timing of the intake valve at the time of shifting of the transmission to the retard side of the opening / closing timing immediately before the start of shifting. A control device for an internal combustion engine, comprising: 3. An intake valve that opens and closes an intake passage that communicates with a combustion chamber of an internal combustion engine, a transmission that is connected to the internal combustion engine and switches its shift state, and a variable valve timing that is capable of changing the opening / closing timing of the intake valve. A mechanism and a timing change prohibiting means for prohibiting a change in the opening / closing timing of the intake valve by the variable valve timing mechanism for reducing the output torque of the internal combustion engine during a shift of the transmission during a sudden acceleration. A control device for an internal combustion engine, which is characterized in that: 4. An intake valve for opening and closing an intake passage communicating with a combustion chamber of an internal combustion engine, an ignition means for igniting a mixture gas sucked into the combustion chamber through the intake passage, and a speed change gear connected to the internal combustion engine. A transmission that switches the state, a variable valve timing mechanism that can freely change the opening / closing timing of the intake valve, and an opening / closing timing of the intake valve during gear shifting of the transmission during acceleration to the advance side by the variable valve timing mechanism. And a timing control means for controlling the ignition timing of the ignition means so as to reduce the output torque of the internal combustion engine.