JPH1130134A - Controller of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller of an internal combustion engine, capable of preventing the increase of fluctuation of the intake valve opening and closing timing as well as providing compatibility of the decrease of vibration in starting of the internal combustion engine and the improvement of output in the cooling period after completion of starting of the engine. SOLUTION: A valve timing adjusting mechanism 17 for adjusting the opening and closing timing of an intake valve 28 is provided on an engine 11. The valve closing timing of the intake valve 28 is made into the most delay state by the mechanism 17 in starting of the engine 11. Since the compression ratio of air in a combustion chamber 25 is decreased in this state, pressure in the combustion chamber 25 in the compression stroke is restrained, and vibration of the engine 11 is decreased. The valve closing timing of the intake valve 28 is made into the most advance state by the mechanism 17 in the cooling period after completion of starting of the engine 11. Since the compression ratio of air in the combustion chamber 25 is increased in this state, pressure in the combustion engine 25 in the compression stroke is increased, and output of the engine 11 is raised.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an internal combustion engine that controls the opening and closing timing of an intake valve at the start of an internal combustion engine and during a cold period after the start of the engine.

[0002]

2. Description of the Related Art Generally, in an internal combustion engine such as an on-vehicle engine, a piston is reciprocated by combustion of a mixed gas sucked into a combustion chamber through an intake passage, and a driving force is obtained by reciprocation of the piston and combustion is performed. The latter mixed gas is discharged to an exhaust passage as exhaust gas. In such an internal combustion engine, the combustion chamber is communicated with the intake and exhaust passages by opening and closing the intake and exhaust valves so that the mixed gas is sucked into the combustion chamber and the exhaust gas is discharged.

[0003] These intake and exhaust valves are opened and closed by rotation of intake and exhaust shafts connected via a belt or the like to a crankshaft, which is an output shaft of the internal combustion engine.
When the mixed gas is sucked into the combustion chamber, the exhaust valve closes and the intake valve opens, and when the exhaust gas is discharged from the combustion chamber, the intake valve closes and the exhaust valve opens.

[0004] Further, in the internal combustion engine configured as described above, the purpose is to improve the output and reduce the emission.
The opening and closing timings of the intake valve and the exhaust valve are appropriately changed. As a device for changing the opening / closing timing of the intake valve and the exhaust valve in this manner, for example, a valve timing control device described in Japanese Patent Application Laid-Open No. 6-346768 is known.

The apparatus includes a driving member that moves so as to change the relative rotation phase of an intake camshaft with respect to a crankshaft, hydraulic chambers provided on both sides in the moving direction of the driving member, And a hydraulic control mechanism for supplying the pressure. Then, the oil is appropriately supplied to and discharged from the hydraulic chamber by the hydraulic control mechanism, and the drive member is moved by the oil pressure of the oil, whereby the relative rotational phase of the intake camshaft with respect to the crankshaft is changed. Thus, by changing the relative rotation phase of the intake camshaft with respect to the crankshaft, the opening / closing timing of the intake valve is changed.

The change of the opening / closing timing of the intake valve is performed, for example, when the opening / closing timing of the intake valve is delayed when the internal combustion engine is running at a low speed, or when the opening / closing timing of the intake valve is advanced when the internal combustion engine is at a high speed.
This is to stabilize the rotation by shortening the valve overlap when the internal combustion engine is running at a low speed, and to increase the intake efficiency of the engine by speeding up the opening of the intake valve when the internal combustion engine is running at a high speed.

[0007]

By the way, when the internal combustion engine is started, that is, from when the crankshaft is started to rotate by a starter motor or the like until the engine starts to operate, the compression is performed to improve the riding comfort of the automobile. Preferably, the pressure in the combustion chamber during the stroke is kept low to reduce vibration of the engine. Therefore, conventionally, at the start of the internal combustion engine, the opening and closing timing of the intake valve is delayed by the valve timing control device, so that the compression ratio of air in the combustion chamber is reduced to reduce the pressure in the combustion chamber during the compression stroke.

However, in this case, even when the internal combustion engine starts operating and the start of the engine is completed, the opening / closing timing of the intake valve is kept delayed, and the air compression ratio in the combustion chamber is kept low. Therefore, the engine output decreases during the cold period immediately after the start of the operation of the engine.

In the cold period of the internal combustion engine,
It is conceivable to improve the output of the internal combustion engine by performing feedback control of the intake valve opening / closing timing, which is performed after the engine warms up. In this feedback control, the hydraulic control mechanism is controlled so that the opening / closing timing of the intake valve coincides with the target opening / closing timing obtained based on the operating state of the engine.

However, during the cold period of the internal combustion engine,
As the time elapses from the start of the operation of the engine, the temperature of the oil for driving the driving member gradually increases, and the viscosity of the oil gradually changes due to the temperature rise. for that reason,
In order to make the opening / closing timing of the intake valve coincide with the target opening / closing timing, it is necessary to variably set the correction amount at the time of executing the feedback control according to the oil temperature rise, but the work involved in the variable setting cannot be ignored. Has become.

If the correction amount is not variably set, a response delay or too fast response to a change in the opening / closing timing of the intake valve with respect to the supply / discharge of oil by the hydraulic control mechanism occurs during the feedback control. I do. As a result, the opening / closing timing of the intake valve does not coincide with the target opening / closing timing, and frequently fluctuates within a predetermined range, so that drivability is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object thereof is to achieve both a reduction in vibration at the start of an internal combustion engine and an improvement in output during a cold period after the start of the engine. It is another object of the present invention to provide a control device for an internal combustion engine that can prevent an increase in fluctuation of the opening / closing timing of an intake valve.

[0013]

According to the first aspect of the present invention, there is provided a valve timing adjusting mechanism for adjusting the opening / closing timing of an intake valve provided in an internal combustion engine, and a driving state of the internal combustion engine. Operating state detecting means for detecting the engine operating state, control means for controlling the drive of the valve timing adjustment mechanism in accordance with the detected engine operating state, based on the detected engine operating state, when the engine is started, the intake valve A correction means is provided for delaying the opening / closing timing and for advancing the opening / closing timing of the intake valve for a predetermined period after the completion of the engine start.

According to this configuration, when the internal combustion engine is started, the opening / closing timing of the intake valve is retarded, so that the pressure in the combustion chamber during the compression stroke of the engine drops. Also,
During a predetermined period after the start of the internal combustion engine, the opening / closing timing of the intake valve is advanced in angle, so that the compression ratio of the air in the combustion chamber of the engine is increased. By correcting the opening / closing timing of the intake valve in this way, it is possible to achieve both a reduction in vibration at the time of starting the internal combustion engine and an improvement in output during a predetermined period after the start of the engine.

According to a second aspect of the present invention, in the control device for an internal combustion engine according to the first aspect, when the advance of the opening / closing timing of the intake valve is corrected by the correcting means, the ignition timing of the engine is retarded. Timing correction means is further provided.

According to this configuration, when the opening / closing timing of the intake valve is advanced in a predetermined period after the start of the internal combustion engine, knocking caused by an increase in the compression ratio of the air in the combustion chamber is delayed by the ignition timing. The corners can prevent this.

According to a third aspect of the present invention, in the control apparatus for an internal combustion engine according to the second aspect, the control apparatus further comprises an opening / closing timing detecting means for detecting an opening / closing timing of the intake valve, and the ignition timing correcting means comprises The correction amount is determined based on the opening / closing timing of the intake valve detected by the opening / closing timing detecting means.

According to this configuration, when the opening / closing timing of the intake valve is advanced, the ignition timing retard correction amount is determined based on the opening / closing timing. Therefore, during a predetermined period after the start of the internal combustion engine, knocking based on the advance correction of the opening / closing timing of the intake valve can be suitably prevented, and the output of the engine can be suitably maintained.

According to a fourth aspect of the present invention, there is provided a valve timing adjusting mechanism which is hydraulically driven to adjust an opening / closing timing of an intake valve provided in an internal combustion engine, an opening / closing timing detecting means for detecting the opening / closing timing of the intake valve,
Operating state detecting means for detecting an operating state of the internal combustion engine; and feedback of driving of the valve timing adjusting mechanism so that the detected opening / closing timing of the intake valve approaches a target opening / closing timing obtained based on the detected engine operating state. Based on the feedback control means for controlling the engine and the detected engine operating state, the opening / closing timing of the intake valve is retarded at the time of engine start, and the feedback control is inhibited during the cold period after the engine start is completed. Correction means for advancing the opening / closing timing of the valve. According to this configuration, in the cold period after the start of the internal combustion engine, when the temperature of the oil for driving the valve timing adjustment mechanism gradually increases and the viscosity of the oil changes, the oil viscosity changes. The feedback control that causes the feedback control amount to be inappropriate due to the above is not performed. Therefore, it is possible to prevent a response delay or a premature response from being caused when the opening / closing timing of the intake valve is changed due to the inappropriate feedback control amount, and to suppress an increase in the fluctuation of the intake valve opening / closing timing based on the response delay or the premature response. Will be able to

According to a fifth aspect of the present invention, in the control apparatus for an internal combustion engine according to the fourth aspect, when the advance of the opening / closing timing of the intake valve is corrected by the correction means, the ignition timing of the engine is corrected by the retard. Timing correction means is further provided.

According to this structure, when the opening / closing timing of the intake valve is advanced in the cold period after the start of the internal combustion engine, knocking caused by an increase in the compression ratio of the air in the combustion chamber is reduced by the ignition timing. It can be prevented by retarding.

According to a sixth aspect of the present invention, in the control apparatus for an internal combustion engine according to the fifth aspect, the ignition timing correction means detects the amount of retard correction by the open / close timing detection means and controls the opening and closing of the intake valve. It was decided based on the timing.

With this configuration, when the opening / closing timing of the intake valve is advanced, the ignition timing retard correction amount is determined based on the opening / closing timing. Therefore, during the cold period after the start of the internal combustion engine, knocking based on the advance correction of the opening / closing timing of the intake valve can be suitably prevented, and the output of the engine can be suitably maintained.

According to a seventh aspect of the present invention, in the control apparatus for an internal combustion engine according to any one of the first to sixth aspects, the correction means performs correction of the opening / closing timing of the intake valve by correcting the delay of the intake valve. The opening / closing timing is corrected to the most retarded timing.

According to this configuration, by setting the opening / closing timing of the intake valve to the most retarded timing, the pressure in the combustion chamber at the time of starting the internal combustion engine can be kept extremely low, and the vibration of the engine can be reduced appropriately. become.

According to an eighth aspect of the present invention, in the control apparatus for an internal combustion engine according to any one of the first to seventh aspects, the correction means corrects the advance of the opening / closing timing of the intake valve. The opening and closing timing is corrected to the most advanced timing.

According to this configuration, in the cold period after the start of the internal combustion engine, it is only necessary to control the valve timing adjusting mechanism so that the opening and closing timing of the intake valve becomes the most advanced timing. Therefore, the control load when performing the advance correction of the intake valve is reduced as compared with the case where the open / close timing of the intake valve is controlled closer to the target open / close timing.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which the present invention is applied to an engine mounted on a so-called hybrid vehicle, which runs by two types of motors, an engine and an electric motor, will be described below with reference to FIGS. . In addition, as an engine for such a hybrid vehicle, a so-called Atkinson cycle engine having higher thermal efficiency than a normal Otto cycle engine is employed. The Atkinson cycle engine delays the closing timing of the intake valve compared to the Otto cycle engine, thereby increasing the expansion ratio without excessively increasing the compression ratio, and efficiently increasing the combustion energy of the mixed gas to the engine output. It is an engine that converts it.

FIGS. 1 and 2 are a side view and a plan view of the engine 11, respectively. Engine 11
Includes a cylinder block 13, a cylinder head 14, and an oil pan 53. The cylinder block 13 has a cylinder head 14 attached to its upper end and an oil pan 53 attached to its lower end.

A crankshaft 12 is rotatably supported below the engine 11. A pulley 12a is attached to the crankshaft 12. An intake camshaft 15 and an exhaust camshaft 16 extending parallel to the crankshaft 12 are rotatably supported on the cylinder head 14. A plurality of intake cams 20 are attached to the intake camshaft 15, and a plurality of exhaust cams 22 are attached to the exhaust camshaft 16. Further, a valve timing adjusting mechanism (VVT) having a pulley 17a at an end of the intake camshaft 15 is provided.
A mechanism 17 is attached, and a pulley 16 a is attached to an end of the exhaust camshaft 16.

The pulley 17a on the intake camshaft 15 side and the pulley 16a on the exhaust camshaft 16 are connected to the pulley 1 of the crankshaft 12 via a timing belt 18.
2a. When the crankshaft 12 rotates by driving the engine 11, the rotation is transmitted to the intake and exhaust camshafts 15 and 16 via the timing belt 18.

A signal rotor 54 is attached to the crankshaft 12. A plurality of protrusions 54 a are formed on the outer peripheral surface of the signal rotor 54 by the crankshaft 12.
Are provided at equal angles about the axis of. Also,
On the side of the signal rotor 54, the protrusion 5 of the rotor 54 is provided.
A crank position sensor 55 that detects 4a and outputs a detection signal is provided. Then, the crankshaft 12 rotates, and each projection 54a of the signal rotor 54 is rotated.
Sequentially pass through the side of the crank position sensor 55, the sensor 55 outputs pulse-like detection signals corresponding to the respective projections 54a.

One projection 34 is provided on the outer peripheral surface of the intake camshaft 15. A cam position sensor 36 that detects the protrusion 34 and outputs a detection signal is provided on a side of the intake camshaft 15. Then, when the intake camshaft 15 rotates and the protrusion 34 passes by the cam position sensor 36 at a predetermined cycle, a detection signal corresponding to the protrusion 34 is output from the sensor 36 at a predetermined cycle. Become like

On the other hand, as shown in FIG. 3, the cylinder block 13 is provided with a water temperature sensor 13a for detecting a cooling water temperature of the engine 11, and a piston 23 which can reciprocate in the block 13. . The piston 23 is connected to the crankshaft 12 via a connecting rod 24, and the connecting rod 24 converts the reciprocating movement of the piston 23 into rotation of the crankshaft 12. Also,
A combustion chamber 25 is provided between the head of the piston 23 and the cylinder head 14. An intake port 26 and an exhaust port 27 provided in the cylinder head 14 communicate with the combustion chamber 25.

The intake port 26 and the exhaust port 27 include:
An intake valve 28 and an exhaust valve 29 are provided, respectively. Then, the intake valve 28 is driven to open and close by the rotation of the intake camshaft 15 to communicate and shut off the intake port 26 and the combustion chamber 25. The exhaust valve 29 is
The exhaust port 27 is driven to open and close by the rotation of the exhaust camshaft 16 so that the exhaust port 27 communicates with the combustion chamber 25. Further, an intake pipe 30 and an exhaust pipe 31 are connected to the intake port 26 and the exhaust port 27, respectively. This intake pipe 30
The inside and the inside of the intake port 26 form an intake passage 32,
An exhaust passage 33 is formed in the exhaust pipe 31 and the exhaust port 27.

A throttle valve 3 for adjusting the amount of air taken into the combustion chamber 25 is provided upstream of the intake pipe 30.
5 are provided. The opening of the throttle valve 35 is adjusted based on the amount of depression of an accelerator pedal (not shown) provided in the cabin of the automobile, and the amount of air taken into the combustion chamber 25 is adjusted by adjusting the opening of the valve 35. Be adjusted. Further, the intake pipe 30 is provided with an intake pressure sensor 37 for detecting a pressure in the intake passage 32 located downstream of the throttle valve 35. Further, a fuel injection valve 38 for injecting fuel into the combustion chamber 25 is provided downstream of the intake pipe 30. When air is drawn into the combustion chamber 25 through the intake passage 32, the fuel injection valve 38 injects fuel toward the combustion chamber 25 to form a mixed gas composed of fuel and air.

On the other hand, the combustion chamber 2
An ignition plug 39a for igniting the mixed gas filled in the fuel cell 5 is provided. This spark plug 39
a is a distributor 3 provided in the engine 11
9 is connected to the igniter module 40. The igniter module 40 includes an ignition coil 40a connected to the distributor 39 and a battery (not shown) of the vehicle, and an igniter 40b for adjusting the ignition timing of the ignition plug 30a.

The igniter 40b applies a high voltage output from the battery to the ignition plug 39a via the distributor 39. The ignition timing of the ignition plug 39a is determined based on the output timing of the high voltage from the battery adjusted by the igniter 40b. When the mixed gas filled in the combustion chamber 25 is ignited by the ignition plug 39a,
The mixed gas burns, and the engine 11 obtains the driving force. Further, the mixed gas burned in the combustion chamber 25 is sent to the exhaust passage 33 as exhaust gas.

Next, the valve timing adjusting mechanism 17
Will be described. As shown in FIG. 4, the intake camshaft 1 provided with the valve timing adjustment mechanism 17 is provided.
5 has its journal 15a rotatably supported by a bearing 14a of the cylinder head 14. The tip (left end in FIG. 4) of the intake camshaft 15 is
It passes through the center of the pulley 17a. The pulley 17a is rotatable with respect to the intake camshaft 15. A rotating member 41 is fixed to a tip end surface of the intake camshaft 15 by bolts 42, and the rotating member 4
Numeral 1 is adapted to rotate integrally with the intake camshaft 15 about the axis L of the shaft.

On the other hand, a housing 43 provided so as to cover the rotating member 41 is in contact with the tip side surface of the pulley 17a. The housing 43 includes a ring cover 44 provided so as to surround the outer periphery of the rotating member 41, and a closing plate 4 provided so as to close a distal end opening of the ring cover 44.
And 5. The pulley 17a, the ring cover 44, and the closing plate 45 are connected by bolts 46 so as to be integrally rotatable about the axis L of the intake camshaft 15.

The intake camshaft 15 is provided with an advance control oil passage 47 and a retard control oil passage 48 for supplying and discharging oil to and from the valve timing adjusting mechanism 17. The advance control oil passage 47 and the retard control oil passage 48 extend to the inside of the rotating member 41 and
4 is connected to an oil control valve (OCV) 49 through the inside of the bearing portion 14a. Also, OCV4
A supply passage 50 and a discharge passage 51 are connected to 9. The supply passage 50 is connected to an oil pan 53 provided below the engine 11 via an oil pump 52 driven by the rotation of the crankshaft 12, and the discharge passage 51 is directly connected to the oil pan 53. I have.

The OCV 49 has a casing 56, and the casing 56 has first and second supply / discharge ports 57, 58.
, First and second discharge ports 59 and 60, and a supply port 61. The first supply / discharge port 57
A retard control oil passage 48 communicates with the second supply / drain port 58.
Is connected to an advance control oil passage 47. Further, the supply passage 61 communicates with the supply port 61, and the discharge ports 59 and 6.
A discharge passage 51 communicates with 0. Further, a spool 63 having four valve portions 64 and urged in opposite directions by a coil spring 62 and an electromagnetic solenoid 65 is provided in the casing 56.

When the electromagnetic solenoid 65 is in the demagnetized state, the spool 63 is disposed at one end (the right side in FIG. 4) of the casing 56 by the urging force of the coil spring 62, and the first supply / discharge port 57 and the first Discharge port 59
And the second supply / discharge port 58 communicates with the supply port 61. In this state, the oil in the oil pan 53 is sent out by the oil pump 52 to the advance control oil passage 47 via the supply passage 50 and the OCV 49, and the oil in the retard control oil passage 48 is discharged to the OCV 49 and the discharge passage. 51
Through the oil pan 53.

When the electromagnetic solenoid 65 is excited, the spool 63 is disposed on the other end (left side in FIG. 4) of the casing 56 against the urging force of the coil spring 62, and the second supply / discharge port 58 is the second discharge port 60
The first supply / discharge port 57 communicates with the supply port 61. In this state, the oil in the oil pan 53 is sent out by the oil pump 52 to the retard control oil passage 48 through the supply passage 50 and the OCV 49, and the oil in the advance control oil passage 47 is removed from the OCV 49 and the discharge passage. The oil is returned to the oil pan 53 via the oil pan 51.

Further, when the voltage application to the electromagnetic solenoid 65 is duty-controlled and the spool 63 is positioned in the middle of the casing 56, the first and second supply / discharge ports 57,5 are provided.
8 is closed, and the movement of oil through the supply / discharge ports 57, 58 is prohibited.

Next, the detailed structure of the rotating member 41 and the housing 43 in the valve timing adjusting mechanism 17 is shown in FIG.
This will be described with reference to FIG. As shown in FIG.
3, three projecting portions 66 protruding toward the axis L of the intake camshaft 15 are formed on the inner peripheral surface 44a of the ring cover 44 at equal intervals in the circumferential direction of the housing 43. A groove 67 is provided between the overhangs 66.
Are formed at equal intervals in the circumferential direction of the housing 43.
On the outer peripheral surface of the rotating member 41, three vanes 68 projecting outward so as to be inserted into the respective groove portions 67 are provided at equal intervals in the circumferential direction of the rotating member 41. The inside of each groove 67 into which each vane 68 is inserted is partitioned into an advance side hydraulic chamber 69 and a retard side hydraulic chamber 70 by the vane 68. The advance hydraulic chamber 69 and the retard hydraulic chamber 70
Are located so as to sandwich the vane 68 from both sides in the circumferential direction of the rotating member 41. The advance control oil passage 47 and the retard control oil passage 48 communicate with the advance hydraulic pressure chamber 69 and the retard hydraulic pressure chamber 70, respectively.

In the valve timing adjusting mechanism 17, when the electromagnetic solenoid 65 of the OCV 49 is demagnetized, oil is supplied from the advance control oil passage 47 to the advance hydraulic chamber 69, and the retard hydraulic oil 69 is supplied. Oil is discharged from the chamber 70 via the retard control oil passage 48. As a result, when each vane 68 moves in the direction of arrow A, the rotating member 41 rotates rightward in the drawing, and the relative rotation phase of the intake camshaft 15 with respect to the pulley 17a is changed. Incidentally, in the valve timing adjusting mechanism 17, the pulley 17 a (housing 43) is based on the rotation of the crankshaft 12 transmitted via the timing belt 18.
The intake camshaft 15 rotates rightward in the figure. Therefore, in this case, the intake camshaft 15 advances with respect to the crankshaft 12, and as a result, the opening / closing timing of the intake valve 28 also advances.

When the electromagnetic solenoid 65 of the OCV 49 is excited, the retard control oil passage 48
And the oil is discharged from the advance-side hydraulic chamber 69 via the advance-side control oil passage 47. As a result, when each vane 68 moves in the direction opposite to the arrow A, the rotating member 41 rotates leftward in the same direction, and the pulley 17a
Is changed in the opposite direction to the above. Valve timing adjustment mechanism 17
In this case, in this case, the intake camshaft 15 is retarded with respect to the crankshaft 12, and as a result, the opening / closing timing of the intake valve 28 is also retarded.

Further, the duty of the voltage application to the electromagnetic solenoid 65 in the OCV 49 is controlled, and the first and second voltages are controlled.
When the supply / discharge ports 57 and 58 are closed, oil circulation through the advance control oil passage 47 and the retard control oil passage 48 is prohibited. As a result, at least one of the advance side hydraulic chamber 69 and the retard side hydraulic chamber 70 is filled with oil, and the relative rotational phase of the intake camshaft 15 with respect to the pulley 17a is fixed. In this case, since the relative rotation phase of the intake camshaft 15 with respect to the crankshaft 12 is fixed, the opening / closing timing of the intake valve 28 is also fixed.

The change of the opening / closing timing of the intake valve 28 described above is, for example, to delay the opening / closing timing of the intake valve 28 when the engine 11 is running at a low speed, or to advance the opening / closing timing of the intake valve 28 when the engine 11 is running at a high speed. This is done when squaring. This is to stabilize the rotation by shortening the valve overlap when the engine 11 is running at a low speed, and to increase the intake efficiency of the engine 11 by speeding up the opening of the intake valve 28 when the engine is running at a high speed.

Here, the manner in which the valve timing adjusting mechanism 17 changes the opening and closing timing of the intake valve 28 and the manner in which the pressure in the combustion chamber 25 changes when the opening and closing timing changes will be described with reference to FIGS. 7 and 8. . FIG.
FIG. 8 shows the crank angle when the intake valve 28 opens and closes, and FIG. 8 is a graph showing the change of the pressure in the combustion chamber 25 with respect to the change of the crank angle.

Normally, the opening / closing timing of the intake valve 28 is adjusted by the valve timing adjusting mechanism 17 so as to be in the state shown in FIG. in this case,
Intake valve 28 has crank angle before top dead center (BTDC)
The valve opens when the angle reaches 6 °, and closes when the crank angle reaches 90 ° after the bottom dead center (ABDC). That is, while the crank angle is between 6 ° before top dead center and 90 ° after bottom dead center, the intake valve 28 is kept open. When the crankshaft 12 is rotated while the opening / closing timing of the intake valve 28 is adjusted as described above, the pressure in the combustion chamber 25 changes as shown by a solid line in FIG. The pressure in the combustion chamber 25 gradually increases as the crank angle approaches the top dead center, and gradually decreases after the crank angle passes the top dead center.

When the opening / closing timing of the intake valve 28 is set to the most advanced timing by the valve timing adjusting mechanism 17, the intake valve 28 has a crank angle of 16 degrees before the top dead center as shown in FIG. When the crank angle reaches 80 ° after the bottom dead center, the valve closes. That is, the intake valve 28 is kept open during a period in which the crank angle is between 16 ° before the top dead center and 80 ° after the bottom dead center. When the opening / closing timing of the intake valve 28 is adjusted in this manner, the crankshaft 1
When 2 is rotated, the pressure in the combustion chamber 25 changes as shown by a broken line in FIG. The pressure indicated by the broken line shows the same transition tendency as that indicated by the solid line, but the maximum value is larger than that indicated by the solid line. This is because the compression ratio of the air in the combustion chamber 25 becomes larger than the normal time when the closing timing of the intake valve 28 is advanced more than the normal time.

Further, when the opening / closing timing of the intake valve 28 is set to the most retarded timing by the valve timing 17, the intake valve 28 is moved to a position where the crank angle becomes 24 ° after the top dead center as shown in FIG. When it becomes
The valve closes when the crank angle reaches 120 ° after the bottom dead center. That is, the crank angle changes from 24 ° after top dead center to 1 after bottom dead center.
During the period of 20 °, the intake valve is kept open. When the crankshaft 12 is rotated while the opening / closing timing of the intake valve 28 is adjusted as described above, the pressure in the combustion chamber 25 changes as shown by a dashed line in FIG. The pressure indicated by the one-dot chain line has the same transition tendency as that indicated by the solid line, but the maximum value is smaller than that indicated by the solid line. This is because if the closing timing of the intake valve 28 is retarded from the normal time, the air compression ratio in the combustion chamber 25 becomes smaller than the normal time.

Next, a lock mechanism 71 provided in the valve timing adjusting mechanism 17 for fixing the opening / closing timing of the intake valve 28 to the most retarded state will be described with reference to FIG.

The lock mechanism 71 includes a lock pin 72 and a coil spring 73 provided on the rotating member 41 of the valve timing adjusting mechanism 17, and a pin hydraulic chamber 74 recessed in the closing plate 45 of the mechanism 17. Have been. The lock pin 72 and the coil spring 73 are
It is inserted into a receiving hole 75 formed in the rotating member 41. The accommodation hole 75 is open on the closing plate 45 side and extends in the same direction as the axis L of the intake camshaft 15. The lock pin 72 moves in the direction of the axis L and comes out of the opening of the housing hole 75.

On the other hand, the pin hydraulic chamber 74 communicates with the advance hydraulic chamber 69 of the valve timing adjusting mechanism 17 via an oil passage (not shown). In addition, the pin hydraulic chamber 74 is located in the closing plate 45 at a position corresponding to the position of the lock pin 72 when the opening / closing timing of the intake valve 28 is the most retarded timing. Therefore, the intake valve 28
When the rotating member 41 is rotated so that the opening / closing timing of the intake valve 28 becomes the most retarded timing, the opening / closing timing of the intake valve 28 becomes the most retarded timing when the lock pin 72 is positioned corresponding to the pin hydraulic chamber 74. Become.

When the opening / closing timing of the intake valve 29 reaches the most retarded timing, the lock pin 72 is opened by the urging force of the coil spring 62 between the bottom of the receiving hole 75 and the pin 72. And is inserted into the pin hydraulic chamber 74. In this state, the rotating member 41 is fixed by the lock pin 72 inserted into the pin hydraulic chamber 74, and the opening / closing timing of the intake valve 28 is also fixed at the most retarded timing.

When oil is supplied to the advance hydraulic chamber 69 to advance the opening / closing timing of the intake valve 28, a part of the oil is supplied from the advance hydraulic chamber 69 to the pin through the oil passage. It flows into the hydraulic chamber 74. This pin hydraulic chamber 74
When the oil flows into the lock pin 72, the oil pressure of the oil acts on the front end face (the left end face in FIG. 4) of the lock pin 72.
Moves against the urging force of the coil spring 73. Then, when the lock pin 72 moves and is pulled out of the pin hydraulic chamber 74, the fixing of the rotating member 41 is released, and the rotating member 41 can be turned.

Next, the electrical configuration of the control device according to this embodiment will be described with reference to FIG. This control device includes an electronic control unit (hereinafter referred to as “ECU”) for controlling the operating state of the engine 11, such as ignition timing control, fuel injection timing control, fuel injection amount control, and idle speed control.
92 are provided. This ECU 92 has a ROM 93, a C
It is configured as a logical operation circuit including a PU 94, a RAM 95, a backup RAM 96, and the like.

Here, the ROM 62 is a memory for storing various control programs and maps referred to when the various control programs are executed.
The arithmetic processing is executed based on various control programs and maps stored in M93. Also, the RAM 95 stores the CPU 9
4 is a memory for temporarily storing the calculation results in step 4, data input from each sensor, and the like.
Is a nonvolatile memory for storing data to be stored when the engine 11 is stopped. And ROM93, CPU
The RAM 94, the RAM 95, and the backup RAM 96 are connected to each other via a bus 97, and are also connected to an external input circuit 98 and an external output circuit 99.

The external input circuit 98 includes a water temperature sensor 13
b, the intake pressure sensor 37, the cam position sensor 36, and the crank position sensor 55 are connected. On the other hand, the igniter 40b and the OC
V49 is connected.

Next, an outline of an opening / closing timing (valve closing timing) control mode and an ignition timing control mode of the intake valve 28 executed through the ECU 92 having the above configuration will be described with reference to a time chart of FIG.

When the engine 11 is started, that is, from when the crankshaft 12 is rotated by the starter motor or the like until the engine 11 starts operating, the closing timing of the intake valve 28 is in the most retarded state (120 ° after the bottom dead center). CA), and is kept at its most retarded state. In this state, the compression ratio of air in the combustion chamber 25 is reduced, so that the pressure in the combustion chamber 25 during the compression stroke is suppressed lower than usual, and the pressure reduction reduces the engine 11.
Vibration generated at the time of starting is reduced.

After the start of the engine 11 is completed,
The closing timing of the intake valve 28 is in the most advanced state (80% after bottom dead center).
(° CA), the advance angle is gradually corrected, and thereafter, the most advanced state is maintained. As described above, by advancing the closing timing of the intake valve 28, the compression ratio of the air in the combustion chamber 25 is increased, and the pressure in the combustion chamber 25 during the compression stroke is higher than normal, so that the engine 11 Immediately after the start of the operation, the output during the cold period is improved.

When the valve closing timing of the intake valve 28 is gradually advanced, the ignition timing is gradually corrected. When the valve closing timing of the intake valve 28 reaches the most advanced state, the ignition timing becomes the most retarded state. By correcting the ignition timing in this way, the intake valve 2
If the pressure in the combustion chamber 25 is excessively increased based on the valve closing timing advance of No. 8, knocking caused by the pressure increase is prevented.

Thereafter, when the cooling water temperature of the engine 11 rises to 10 ° C. or more, the actual opening / closing timing of the intake valve 28 is feedback-controlled so as to approach the target opening / closing timing obtained based on the operating state of the engine 11. Therefore, the closing timing of the intake valve 28 is
It is no longer maintained in the most advanced state. Further, the ignition timing is returned from the retarded state to the original state.

Next, the intake valve 28 of this embodiment
Will be described with reference to FIG.
FIG. 11 is a flowchart showing a processing routine for controlling the opening / closing timing. This processing routine is executed by the ECU 92 at predetermined time intervals by interruption.

In the processing routine, the ECU 92 determines whether or not the engine 11 is in the start mode as the processing of step S101. That is, the engine speed obtained based on the detection signal from the crank position sensor 55 is a value when the crankshaft 12 is rotated by a starter motor or the like (for example, 300 to 500 rpm).
If m), it is determined in step S101 that the engine is in the start mode, and the process proceeds to step S102.

The ECU 92 holds the electromagnetic solenoid 65 of the OCV 49 in the excited state so that the opening and closing timing of the intake valve 28 is corrected to the most retarded timing as the process of step S102. When the opening / closing timing of the intake valve 28 reaches the most retarded timing, the rotation member 40 of the valve timing adjustment mechanism 17 is fixed by the lock mechanism 71 so as not to rotate. By fixing the rotating member 40, the opening / closing timing of the intake valve 28 is fixed at the most retarded timing.

When the opening / closing timing of the intake valve 28 is corrected to the most retarded timing, the closing timing of the intake valve 28 is retarded more than usual, so that the combustion chamber 25
The compression ratio of the air inside becomes smaller. As a result, the pressure in the combustion chamber 25 during the compression stroke is suppressed lower than usual, and the pressure reduction reduces the vibration generated when the engine 11 starts. After the processing of step S102 as described above is performed, the ECU 92 temporarily ends the processing routine.

On the other hand, if it is determined in step S101 that the engine is not in the start mode, that is, if the engine speed is not the value (300 to 500 rpm) when the crankshaft 12 is rotated by the starter motor or the like, the process proceeds to step S101. Proceed to S103. The ECU 92 determines in step S10
In the process of 3, it is determined whether or not the cooling water temperature of the engine 11 is, for example, 10 ° C. or higher based on the detection signal from the water temperature sensor 13b. If the cooling water temperature is lower than 10 ° C., it is determined that the engine 11 is in the cold period immediately after the start is completed, and the process proceeds to step S104.

As the process of step S104, the ECU 92 demagnetizes the electromagnetic solenoid 65 of the OCV 49 and corrects the opening / closing timing of the intake valve 28 to the most advanced timing. The electromagnetic solenoid 6 of the OCV 49
By keeping 5 in the demagnetized state, the opening / closing timing of the intake valve 28 becomes the most advanced timing and is held at the most advanced timing. And the intake valve 28
When the opening / closing timing of the valve becomes the most advanced timing, the closing timing of the valve 28 is advanced more than usual, so that the combustion chamber 2
5, the compression ratio of the air is increased. As a result, the pressure in the combustion chamber 25 during the compression stroke is higher than usual, and the increase in the pressure improves the output during the cold period immediately after the start of the operation of the engine 11. After the processing of step S104 as described above is executed, the ECU 92 once ends the processing routine.

In step 103, the engine 11
If it is determined that the engine is not in the cold state immediately after the start is completed, that is, if the coolant temperature of the engine 11 is equal to or higher than 10 ° C., the process proceeds to step S105. The ECU 92 performs the process of step S105 so that the actual opening / closing timing of the intake valve 28 approaches the target opening / closing timing calculated based on the engine load and the engine speed.
The feedback control is performed on V49.

The actual opening / closing timing of the intake valve 28 is obtained based on detection signals from the cam position sensor 36 and the crank position sensor 55. Further, the engine load and the engine speed are obtained based on detection signals from the intake pressure sensor 37 and the crank position sensor 55, respectively. When calculating the target opening / closing timing, a well-known map obtained in advance by experiment and stored in the ROM 93 is referred to. After the processing of step S105 as described above is performed, the ECU 92 temporarily ends the processing routine.

Next, the procedure for retarding the ignition timing in this embodiment will be described with reference to FIG. This FIG.
It is a flowchart which shows the processing routine for the said ignition timing retard control. This processing routine is executed by the ECU 92 at an angle interruption every predetermined crank angle.

In the same processing routine, the ECU 92 determines that the cam position sensor 3
6 and a detection signal from the crank position sensor 55, it is determined whether or not the opening / closing timing of the intake valve 28 has been advanced to the most advanced timing. If the opening / closing timing of the intake valve 28 has not been advanced to the most advanced timing, the ECU 92 once ends this processing routine. When the opening / closing timing of the intake valve 28 has been advanced to the most advanced timing, the process proceeds to step S202.

In the process of step S202, EC
U92 is a value obtained by adding an ignition timing correction amount AVVT calculated based on the closing timing of the intake valve 28 (opening and closing timing of the intake valve 28) to the basic ignition timing ABSE calculated from the engine load, the engine speed, and the like. The final ignition timing AOP is set, and then the processing routine is temporarily terminated. When calculating the basic ignition timing ABSE, a known map obtained in advance by experiment and stored in the ROM 93 is referred to. When calculating the ignition timing correction amount AVVT, a map shown in FIG. 10A obtained in advance by experiment and stored in the ROM 93 is referred to.

As is apparent from this map, the calculated ignition timing correction amount AVVT becomes “0” when the closing timing of the intake valve 28 is more retarded than 90 ° after the bottom dead center. Further, the closing timing of the intake valve 28 is 90 ° after the bottom dead center.
The ignition timing correction amount AVVT calculated above has a transition tendency that increases as the valve closing timing of the intake valve 28 shifts to the advanced side.

Accordingly, the final ignition timing AOP calculated in the process of step S202 changes as indicated by the solid line in the graph of FIG. 10B with respect to the change of the closing timing of the intake valve 28. That is, the final ignition timing AOP is constant with respect to a change in the closing timing of the intake valve 28 when the closing timing of the intake valve 28 is more advanced than 90 ° after the bottom dead center. When it is between 90 ° and 80 ° later, it gradually shifts to the retard side with the advance of the valve closing timing.

The ECU 92 adjusts the actual ignition timing by controlling the output timing of the high voltage to the ignition plug 39a adjusted by the igniter 40b based on the final ignition timing AOP calculated in step S202. By such ignition timing adjustment, in the cold period immediately after the start of the engine 11, the ignition timing gradually shifts to the retard side as the opening / closing timing of the intake valve 28 shifts to the most advanced timing. become.

Accordingly, during the cold period immediately after the start of the engine 11 is completed, the occurrence of knocking due to the excessive increase in the pressure in the combustion chamber 25 based on the advance timing of the closing timing of the intake valve 28 is determined by the ignition timing. Prevention can be suitably prevented by retard correction. Further, since the ignition timing correction amount AVVT increases as the valve closing timing of the intake valve 28 advances, the valve closing timing advance amount of the intake valve 28 is relatively small, and the pressure in the combustion chamber 25 becomes excessive. If the ignition timing does not increase, the ignition timing is excessively corrected for the retard and the engine 11
Can be prevented from being lowered.

According to the present embodiment in which the processing described in detail above is performed, the following effects can be obtained. When the engine 11 is started, the closing timing of the intake valve 28 is retarded to the most retarded state (120 ° CA after bottom dead center), and the air compression ratio in the combustion chamber 25 becomes a very small value. . Therefore, the pressure in the combustion chamber 25 can be kept extremely low when the engine 11 starts, and the vibration of the engine 11 at the time of starting can be suitably reduced.

A hybrid vehicle on which the engine 11 is mounted runs while switching between the engine 11 and the electric motor, so that the engine 11 is frequently started and stopped. Therefore, when the engine 11 starts, the intake valve 2
By retarding the valve closing timing of 8 to reduce vibration,
Riding comfort is more suitably improved than in the case of a normal automobile.

During the cold period after the start of the engine 11, the valve closing timing of the intake valve 28 is advanced and the compression ratio of air in the combustion chamber 25 is increased. for that reason,
During the cold engine period after the start is completed, the pressure in the combustion chamber 25 during the compression stroke is increased, and the output of the engine 11 is improved. Therefore, in the present embodiment, it is possible to achieve both a reduction in vibration at the time of starting and an improvement in output during a cold period after the start is completed.

The correction of the advance timing of the closing timing of the intake valve 28 during the cold period is merely performed so that the closing timing is the most advanced. Therefore, it is possible to reduce the control load when performing the advance correction, as compared with the case where the advance control of the valve closing timing of the intake valve 28 is performed by performing the feedback control.

In general, during the cold period after the start of the engine 11, the temperature of the oil for driving the valve timing adjusting mechanism 17 gradually rises, and the oil viscosity changes due to the temperature change. Become like When the feedback control for the closing timing of the intake valve 28 is executed in such a situation where the oil viscosity change occurs, the control amount becomes an inappropriate value due to the oil viscosity change, and a response delay occurs when the closing timing of the intake valve 28 is changed. And response too early. However, in this embodiment, during the cold period of the engine 11, the valve closing timing of the intake valve 28 is advanced without being subjected to feedback control. It is possible to suppress an increase in valve timing fluctuation.

When the engine 11 is started, the intake valve 28
When the valve closing timing is corrected to the most retarded state, the closing timing of the intake valve 28 is fixed by the lock mechanism 71 provided in the valve timing adjusting mechanism 17. Therefore, the closing timing of the intake valve 28 is accurately maintained in the most retarded state, and the pressure in the combustion chamber 25 during the compression stroke can be accurately maintained in an extremely low state.

In the cold period immediately after the start of the engine 11, the ignition timing is retarded in accordance with the advance of the valve closing timing of the intake valve 28, so that the valve closing timing of the intake valve 28 is advanced. Based on this, it is possible to prevent occurrence of knocking due to excessive increase in the pressure in the combustion chamber 25.

The correction amount of the ignition timing retard correction increases as the valve closing timing of the intake valve 28 advances.
Therefore, when the valve closing timing advance amount of the intake valve 28 is relatively small and the pressure in the combustion chamber 25 does not increase excessively, the ignition timing is too retarded and the output of the engine 11 is reduced. Can be prevented. Therefore, during the cold period after the start of the engine 11 is completed, knocking based on the advance timing of the closing timing of the intake valve 28 can be suitably prevented, and the output of the engine 11 can be suitably maintained.

The present embodiment can be modified, for example, as follows. In the present embodiment, the ignition timing retard correction amount is increased as the valve closing timing of the intake valve 28 advances, but the ignition timing retard correction may be performed by a fixed amount. In this case, since it is not necessary to detect the closing timing of the intake valve 28 and calculate the ignition timing correction amount AVVT based on the advance amount of the valve closing timing, the control burden when performing the ignition timing retard correction is reduced. Can be reduced.

When the closing timing of the intake valve 28 is advanced during the cold period after the start of the engine 11 is completed, it is not always necessary to retard the ignition timing. In this case, engine 1
The control load on the ECU 92 can be reduced because the ignition timing does not need to be retarded during one cold period.

In the lock mechanism 71 of the present embodiment, the lock pin 72 is provided on the rotating member 41 and the pin hydraulic chamber 74 is provided on the closing plate 45, but the present invention is not limited to this.
That is, the lock pin 72 may be provided on the closing plate 45 and the pin hydraulic chamber 74 may be provided on the rotating member 41, and the positional relationship between the two may be reversed from that of the embodiment.

In the present embodiment, only the lock mechanism 71 for fixing the valve closing timing of the intake valve 28 to the most retarded state is illustrated. However, another lock mechanism for fixing the valve closing timing to the most advanced state is provided. It may be provided. In this case, when the closing timing of the intake valve 28 is set to the most advanced state during the cold period after the start of the engine 11 is completed, the closing timing of the intake valve 28 is set to the most advanced state by the lock mechanism. Will be retained. Therefore, during the cold period after the start of the engine 11, the compression ratio of the air in the combustion chamber 25 is accurately maintained at a high level, and the pressure in the combustion chamber 25 during the compression stroke is accurately and extremely high. Can be held.

The lock mechanism 71 may be omitted, and the configuration of the valve timing adjusting mechanism 17 may be simplified. In the present embodiment, in the cold period after the start of the engine 11, the valve closing timing of the intake valve 28 is advanced until the valve is advanced to the most advanced state, but it is not always necessary to make the most advanced state.

In the present embodiment, when the engine 11 is started, the valve closing timing of the intake valve 28 is retarded until it reaches the most retarded state. However, it is not always necessary to make it the most retarded state. In the present embodiment, the vane-type valve timing adjusting mechanism 17 is illustrated, but other types of valve timing adjusting mechanisms may be used instead. For example, by moving the ring gear in the axial direction of the intake camshaft 15, the intake camshaft 1 with respect to the crankshaft 12 is moved.
5, a valve timing adjustment mechanism of a type that changes the relative rotation phase may be employed. An intake cam whose cam profile continuously changes in the direction of the axis L of the intake camshaft 15 is provided.
A valve timing adjustment mechanism of a type that changes the opening / closing timing of the intake valve 28 by moving the intake valve 28 in the direction of the axis L may be adopted. In this case, depending on the cam profile setting of the intake cam, only the valve closing timing can be changed without changing the valve opening timing of the intake valve 28. Even when this type of valve timing adjustment mechanism is employed, the same effects as in the above embodiment can be obtained. In this type of valve timing adjusting mechanism, driving by a step motor or the like can be adopted instead of employing hydraulic driving.

The present invention may be applied to a diesel engine instead of a gasoline engine. In the present embodiment, the present invention is applied to the engine 11 of the Atkinson cycle mounted on the hybrid vehicle. However, the present invention may be applied to the engine of the Otto cycle mounted on a normal vehicle instead. In this case, the opening / closing timing of the intake valve 28 is entirely shifted to the advanced side as compared with the case of the present embodiment.

Next, technical ideas other than the claims that can be grasped from the above embodiments are described below together with their effects. 9. The control device for an internal combustion engine according to claim 7, wherein the valve timing adjusting mechanism opens and closes the intake valve when the intake valve is corrected to at least one of a most advanced timing and a most retarded timing. A control device for an internal combustion engine having timing fixing means for fixing timing.

According to this configuration, when the opening and closing timing of the intake valve is fixed to the most retarded timing by the timing fixing means at the time of starting the internal combustion engine, the pressure in the combustion chamber in the compression stroke of the engine is accurately kept at an extremely low state. Will be able to Further, when the intake valve opening / closing timing is fixed to the most advanced timing by the timing fixing means after the start of the internal combustion engine, the pressure in the combustion chamber can be accurately maintained at a high level.

[0100]

According to the first aspect of the present invention, when the internal combustion engine is started, the opening / closing timing of the intake valve is retarded, so that the pressure in the combustion chamber during the compression stroke decreases.
During a predetermined period after the completion of the start of the engine, the opening / closing timing of the intake valve is advanced and the compression ratio of the air in the combustion chamber is increased. Therefore, it is possible to achieve both the reduction of the vibration at the time of starting the internal combustion engine and the improvement of the output for a predetermined period after the start of the engine.

According to the second aspect of the present invention, when the opening / closing timing of the intake valve is advanced in a predetermined period after the start of the internal combustion engine, knocking caused by an increase in the compression ratio of the air in the combustion chamber is prevented. This can be prevented by retarding the ignition timing.

According to the third aspect of the invention, when the opening / closing timing of the intake valve is advanced, the ignition timing retard correction amount is determined based on the opening / closing timing. Therefore, during a predetermined period after the start of the internal combustion engine, knocking based on the advance correction of the opening / closing timing of the intake valve can be suitably prevented, and the output of the engine can be suitably maintained.

According to the present invention, during the cold period after the start of the internal combustion engine is completed, the feedback control is not performed so that the opening / closing timing of the intake valve becomes the target opening / closing timing. Therefore, when the temperature of the oil for driving the valve timing adjustment mechanism gradually rises during the cold period of the engine and its viscosity changes, it is possible to prevent the feedback control amount from becoming inappropriate due to the change in the oil viscosity. Is done. And as a result, it is possible to prevent a response delay or a too fast response from occurring when the opening / closing timing of the intake valve is changed due to an inappropriate feedback control amount.
It is possible to suppress an increase in fluctuation of the intake valve opening / closing timing based on these.

According to the fifth aspect of the present invention, when the opening / closing timing of the intake valve is advanced in the cold period after the start of the internal combustion engine, the knocking caused by the increase in the compression ratio of the air in the combustion chamber is performed. Can be prevented by retarding the ignition timing.

According to the present invention, when the opening / closing timing of the intake valve is advanced, the ignition timing retard correction amount is determined based on the opening / closing timing. Therefore, during the cold period after the start of the internal combustion engine, knocking based on the advance correction of the opening / closing timing of the intake valve can be suitably prevented, and the output of the engine can be suitably maintained.

According to the seventh aspect of the invention, the opening and closing timing of the intake valve is set to the most retarded timing, so that the pressure in the combustion chamber at the time of starting the internal combustion engine is extremely low, and the vibration of the engine is suitably reduced. be able to.

According to the eighth aspect of the invention, in the cold period after the start of the internal combustion engine, it is only necessary to control the valve timing adjusting mechanism so that the opening / closing timing of the intake valve becomes the most advanced timing. Therefore, the control load when performing the advance correction of the intake valve is reduced as compared with the case where the open / close timing of the intake valve is controlled closer to the target open / close timing.

[Brief description of the drawings]

FIG. 1 is a front view showing an entire engine to which a control device according to an embodiment is applied.

FIG. 2 is a plan view showing a cylinder head of the engine.

FIG. 3 is a sectional view showing the internal structure of the engine.

FIG. 4 is a cross-sectional view showing a valve timing adjusting mechanism and an oil supply / discharge structure for the mechanism.

FIG. 5 is a sectional view showing the internal structure of the valve timing adjustment mechanism.

FIG. 6 is a block diagram showing an electrical configuration of the control device.

FIG. 7 is a timing chart showing the opening / closing timing of an intake valve.

FIG. 8 is a graph showing the pressure in the combustion chamber when the engine is started.

FIG. 9 is a time chart showing a valve closing timing control mode and an ignition timing control mode of the intake valve according to the embodiment.

FIG. 10 is a map referred to when calculating the ignition timing correction amount, and a graph showing the relationship between the closing timing of the intake valve and the final ignition timing.

FIG. 11 is a flowchart showing a procedure for controlling the opening / closing timing of the intake valve according to the embodiment;

FIG. 12 is a flowchart showing an ignition timing control procedure in the embodiment.

[Explanation of symbols]

11 engine, 13b water temperature sensor, 17 valve timing adjustment mechanism, 28 intake valve, 36 cam position sensor, 37 intake pressure sensor, 39a ignition plug, 40 igniter module, 40a ignition coil, 40b Igniter, 49: oil control valve (OCV), 55: crank position sensor, 92: electronic control unit (ECU).

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F02D 43/00 301 F02D 43/00 301B F02P 5/15 F02P 5/15 B

Claims (8)

[Claims] A valve timing adjusting mechanism for adjusting an opening / closing timing of an intake valve provided in the internal combustion engine; an operating state detecting means for detecting a handing state of the internal combustion engine; Control means for controlling the driving of the valve timing adjusting mechanism; and, based on the detected engine operating state, the opening / closing timing of the intake valve is retarded at the time of engine start, and the intake valve is controlled for a predetermined period after the engine start is completed. A control unit for advancing the opening / closing timing of the internal combustion engine. 2. The control device for an internal combustion engine according to claim 1, further comprising: an ignition timing correction means for delaying the ignition timing of the engine when the advancement of the opening / closing timing of the intake valve is corrected by the correction means. A control device for an internal combustion engine, comprising: 3. The control device for an internal combustion engine according to claim 2, further comprising opening / closing timing detecting means for detecting opening / closing timing of said intake valve, wherein said ignition timing correcting means determines the retardation correction amount by said opening / closing timing. A control device for an internal combustion engine, which is determined based on the opening / closing timing of the intake valve detected by a detecting means. 4. A valve timing adjusting mechanism which is hydraulically driven to adjust the opening / closing timing of an intake valve provided in the internal combustion engine; an opening / closing timing detecting means for detecting the opening / closing timing of the intake valve; Operating state detecting means for detecting, and feedback control means for performing feedback control on driving of the valve timing adjusting mechanism so that the detected opening / closing timing of the intake valve approaches a target opening / closing timing obtained based on the detected engine operating state. Based on the detected engine operation state, the opening / closing timing of the intake valve is retarded when the engine is started, and the feedback control is inhibited during the cold period after the completion of the engine start to advance the opening / closing timing of the intake valve. An internal combustion engine comprising: a correction unit configured to correct an angle. The control device. 5. The control apparatus for an internal combustion engine according to claim 4, further comprising: an ignition timing correction means for correcting the ignition timing of the engine by retarding when the correction means advances the opening / closing timing of the intake valve. A control device for an internal combustion engine, comprising: 6. A control device for an internal combustion engine according to claim 5, wherein said ignition timing correction means determines the retard correction amount based on the opening / closing timing of said intake valve detected by said opening / closing timing detecting means. 7. The internal combustion engine according to claim 1, wherein the correction means corrects the opening / closing timing of the intake valve to the most retarded timing when correcting the opening / closing timing of the intake valve. Control device. 8. The internal combustion engine according to claim 1, wherein the correction means corrects the opening / closing timing of the intake valve to the most advanced timing when correcting the advance timing of the opening / closing timing of the intake valve. Control device.