JPH08270468A - Valve timing control device for internal combustion engine - Google Patents

Abstract

PURPOSE: To eliminate the influence of dispersion of an actual displacement angle, to improve control accuracy, and to suppress mislearning at the time of learning the dispersion of the actual displacement angle. CONSTITUTION: An ECU 70 computes an actual displacement angle VTB on the basis of a displacement timing signal inputted from a cam angle sensor 44, and a cam angle signal (reference timing signal) first inputted from a crank angle sensor 40 after the input of the displacement timing signal. The ECU 70 also stores the deviation of each actual displacement angle VTB to the successively averaged actual displacement angle VTBA, obtained by successively averaging the actual displacement angles VTB, as a learning actual displacement angle GVTB, and computes a calibrated actual displacement angle VT by calibrating each actual displacement angle VTB using the learning actual displacement angle GVTB. In addition, whether an intake side camshaft 23 is in course of displacement is judged by each actual displacement angle VTB, and in the case of the camshaft 23 being judged to be in course of displacement, the storage of the learning actual displacement angle GVTB is inhibited.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve timing control device for an internal combustion engine which changes valve timing by displacing a displacement angle of a camshaft with respect to a crankshaft in accordance with an operating state, and more specifically, a crankshaft. The present invention relates to a valve timing control device for an internal combustion engine, which can accurately calculate the displacement angle of the camshaft with respect to.

[0002]

2. Description of the Related Art Conventionally, a valve timing control device for changing the valve opening timing (valve timing) of at least one of an intake valve and an exhaust valve has been put into practical use according to the operating state of an engine. According to this valve timing control device, the period in which the intake valve and the exhaust valve are opened simultaneously (valve overlap period) can be set to an arbitrary period, so that the combustion efficiency in the combustion chamber can be improved.

Japanese Unexamined Patent Publication No. 59-105911 discloses a valve timing control device for changing the valve timing by displacing the rotational phase (displacement angle) of the camshaft with respect to the crankshaft. In such a valve timing device, a crank angle signal generated each time the crankshaft makes one rotation and a cam angle signal generated each time the camshaft makes one rotation are detected, and an actual rotation phase is detected based on the detected both angle signals. (Actual displacement angle) is calculated.

Here, each angle signal is detected by a magnetic rotor and an electromagnetic pickup which form an angle sensor. That is, a plurality of equiangular teeth formed on the outer circumference of the magnetic rotor connected to each shaft generate pulse signals by passing in front of the electromagnetic pickup,
It is detected as an angle signal. Then, feedback control is performed to converge the calculated actual displacement angle to the target rotation phase (target displacement angle) determined based on the operating state of the engine.

Therefore, when the camshaft is displaced with respect to the crankshaft, the valve opening timing of the intake valve or the exhaust valve driven by the camshaft is changed, and the valve overlap period suitable for the operating condition of the engine. Can be realized.

[0006]

However, the magnetic rotors forming the angle sensor have tolerances, and the magnetic rotors are formed not only between different magnetic rotors but also around the same magnetic rotor. The intervals between the plurality of equiangular teeth are not necessarily equiangular, and there is a problem in that the generated angle signals vary. In addition, there is a problem that an error occurs when the electromagnetic pickup is attached, and thus the generated angle signal varies.

Therefore, the actual displacement angle calculated based on the angle signal also changes, and the convergence is determined by whether or not the absolute value of the difference between the actual displacement angle and the target displacement angle is less than or equal to the threshold value. In this case, there is a problem that it is difficult to judge the convergence unless a large value is used as the threshold value. In addition, since it is difficult to determine the convergence and the feedback control is continuously executed, the number of times of operation of the oil control valve increases, and there is a problem that reliability decreases.

On the other hand, if a large value is used as the threshold value, the convergence judgment can be made easily, but it is not possible to accurately realize the optimum valve timing for the operating state of the engine, and the EGR amount in the combustion chamber varies. However, there is a problem that the engine output characteristic is deteriorated and the emission varies.

As a means for improving the deterioration of the control accuracy due to the variation of the angle signal, the learning control for storing the variation of the angle signal and calibrating the angle signal detected next time by using the stored variation of the angle signal is performed. It is possible to carry out. However, in the valve timing control device, the valve timing is changed by rotating the camshaft relative to the crankshaft. Therefore, the timing of generating the angle signal is also changed during the displacement of the camshaft. It is shifted one after another. Therefore, if the learning control is simply executed, there arises a problem that the variation during the displacement of the camshaft (while the valve timing is being changed) is erroneously learned as the steady variation.

Therefore, it is conceivable to prohibit the learning control while the valve timing control device is under displacement control. Then, in determining whether or not the camshaft is displaced, conventionally, the determination has been performed based on a successive average value of the cam angle signals of several times (for example, three cam angle signals).

However, in such a case, for example, when the judgment is made by the successive average value of the three cam angle signals, in order to eliminate the influence of the cam angle signal generated by the previous rotation of the cam shaft, at least 6 times are required. It is necessary to detect the cam angle signal of. Further, since the successive average value is affected by the immediately preceding cam angle signal, it cannot be said that it accurately represents the displacement of the camshaft. Therefore, there is a problem that the displacement of the camshaft cannot be quickly and accurately determined.

The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to eliminate the influence of variations in the actual displacement angle and improve the control accuracy in a valve timing control device. . Further, it is intended to suppress erroneous learning when learning the variation of the actual displacement angle.

[0013]

In order to achieve the above object, a valve timing control device for an internal combustion engine according to the invention of claim 1 is rotationally driven in synchronization with a crankshaft M2 of an internal combustion engine M1 which rotates. The intake side camshaft M3 and the exhaust side camshaft M4 are driven at predetermined timings in synchronization with the rotations of the camshafts M3 and M4, and the intake passage M6 and the exhaust passage M7 that communicate with the combustion chamber M5 are opened and closed. Intake valve M8 and exhaust valve M9, operating state detecting means M10 for detecting the operating state of the internal combustion engine M1, and a reference for generating a reference timing signal for each predetermined crank angle with the rotation of the crankshaft M2. Timing signal generating means M11 and the intake side camshaft with respect to the crankshaft M2 3 or the exhaust camshaft M4
A variable valve timing mechanism M12 for changing the valve timing of at least one of the intake valve M8 and the exhaust valve M9 by displacing at least one of the displacement angles, and the operating state detecting means M.
10, a target displacement angle determining means M13 for determining a target displacement angle of the camshaft on the side where the variable valve timing mechanism M12 is disposed, and the variable valve timing mechanism M12 according to the operating state of the internal combustion engine M1. Based on the displacement timing signal generating means M14 for generating a displacement timing signal at least once every one rotation of the camshaft on the installation side and the displacement timing signal and the reference timing signal, the variable with respect to the crankshaft M2. The actual displacement angle calculating means M15 for calculating the actual displacement angle of the camshaft on the side where the valve timing mechanism M12 is disposed, and the actual displacement angle is sequentially averaged every predetermined number of times to calculate the average displacement angle. A bias that stores the deviation of the actual displacement angle from the sequential average displacement angle. Using the storage means M16 and the deviation stored in the deviation storage means M16, the calibration means M17 for calibrating the actual displacement angle calculated by the actual displacement angle calculation means M15, and the calibration means M17 A valve timing control means M18 for controlling the variable valve timing mechanism M12 so as to converge the actual displacement angle to the target displacement angle is provided as a configuration.

A valve timing control device for an internal combustion engine according to a second aspect of the present invention is the valve timing control device for an internal combustion engine according to the first aspect, wherein the valve timing is changed by the variable valve timing mechanism M12. If it is determined that the valve timing is being changed,
A memory prohibiting means M19 for prohibiting the deviation memory means M16 from storing the deviation of the actual displacement angle with respect to the successive average displacement angle is provided as a configuration.

Further, a valve timing control device for an internal combustion engine according to a third aspect of the present invention is the valve timing control device for an internal combustion engine according to the second aspect, wherein the storage prohibiting means M19 is the displacement timing signal generating means. M
Based on the actual displacement angle corresponding to the same displacement timing signal generated by 14, the variable valve timing mechanism M12 determines whether or not the valve timing is being changed.

[0016]

In the valve timing control device for an internal combustion engine according to the present invention having the above-mentioned structure, the internal combustion engine M
When 1 is started, the crankshaft M2 starts rotating motion. Then, the rotational movement of the crankshaft M2 is
It is transmitted to the intake side camshaft M3 and the exhaust side camshaft M4, and both camshafts M3 and M4 are rotationally driven in synchronization with the rotation of the crankshaft M2. Further, the intake valve M8 and the exhaust valve M9 are both camshafts M
3 and M4 are driven at a predetermined timing in synchronism with the rotations of M3 and M4, and an intake passage M6 and an exhaust passage M, which communicate with the combustion chamber M5.
Open and close 7.

The operating state detecting means M10 detects the operating state of the internal combustion engine M1, and the target displacement angle determining means M1.
Reference numeral 3 denotes the camshaft M on the side where the variable valve timing mechanism M12 is arranged, according to the operating state of the internal combustion engine M1 detected by the operating state detecting means M10.
3. Determine the target displacement angle of M4. Further, the reference timing signal generating means M11 generates a reference timing signal for each predetermined crank angle with the rotation of the crankshaft M2.

The variable valve timing mechanism M12 displaces the displacement angle of at least one of the intake side camshaft M3 and the exhaust side camshaft M4 with respect to the crankshaft M2, and thereby at least one of the intake valve M8 and the exhaust valve M9. Timing is changed.

The displacement timing signal generating means M14 generates a displacement timing signal at least once every one rotation of the camshafts M3 and M4 on the side where the variable valve timing mechanism M12 is arranged. Then, the actual displacement angle calculating means M15 is a variable valve for the crankshaft M2, based on the reference timing signal generated by the reference timing signal generating means M11 and the displacement timing signal generated by the displacement timing signal generating means M14. The actual displacement angle of the camshaft on the side where the timing mechanism M12 is arranged is calculated.

The deviation storage means M16 calculates a sequential average displacement angle by sequentially averaging the actual displacement angles calculated by the actual displacement angle calculation means M15 every predetermined number of times, and calculates each actual average displacement angle with respect to each actual displacement angle. The deviation of the displacement angle is stored for each corresponding actual displacement angle. Further, the calibrating means M17 uses the deviations corresponding to the respective actual displacement angles stored by the deviation storing means M16 to calculate the actual displacement angle calculating means M.
Each actual displacement angle calculated by 15 is calibrated.

The valve timing control means M18
Is the actual displacement angle formed by the calibration means M17,
The variable valve timing mechanism M12 is controlled so as to converge to the target displacement angle.

Further, in the valve timing control device for the internal combustion engine according to the second aspect of the invention, the memory prohibiting means M1 is used.
Reference numeral 9 determines whether or not the variable valve timing mechanism M12 is controlled by the valve timing control means M18 and the valve timing is being changed. When it is determined that the valve timing is being changed, the storage of each actual displacement angle with respect to the successive average displacement angle executed by the deviation storage unit M16 is prohibited.

Further, in the valve timing control device for the internal combustion engine according to the third aspect of the invention, the memory inhibiting means M is provided.
The variable valve timing mechanism M12 is controlled by the valve timing control means M18 based on the actual displacement angle corresponding to the same displacement timing signal generated by the displacement timing signal generation means M14, and the valve timing is changed. It is determined whether it is in the middle.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a valve timing control device for an internal combustion engine will be described below with reference to the drawings.

First, the configuration of the valve timing control device VC for an internal combustion engine according to this embodiment will be described with reference to FIGS. 2 and 3. FIG. 2 is a schematic configuration diagram showing a gasoline engine system to which this embodiment is applied.

An engine 10 as an internal combustion engine includes a cylinder block 11 having a plurality of cylinders formed therein, a cylinder head 12 connected to an upper portion of the cylinder block 11, and a vertical reciprocating movement in each cylinder of the cylinder block 11. And a piston 13 that operates. A crankshaft 14 is connected to the lower end of the piston 13, and the crankshaft 14 is rotated by vertically moving the piston 13.

In the vicinity of the crankshaft 14,
A crank angle sensor 40 is provided, and the crank angle sensor 40 includes a magnetic rotor 40a connected to the crankshaft 14 and an electromagnetic pickup 40b. Here, equiangular teeth are formed on the outer circumference of the rotor 40a, and for example, in the present embodiment, a pulse shape is formed at intervals of 30 ° CA each time the equiangular teeth of the rotor 40a pass in front of the electromagnetic pickup 40b. A crank angle signal is generated.

Further, by measuring the number of crank angle signals generated from the crank angle sensor 40 after the reference position signal is generated by the cylinder discrimination sensor 42, which will be described later, the ECU
At 70 (described later), the rotational speed of the crankshaft 14 (engine speed NE) is calculated.

The space defined by the inner walls of the cylinder blocks 11 and the cylinder head 12 and the top of the piston 13 defines a combustion chamber 1 for burning the air-fuel mixture.
5, a spark plug 16 for igniting the air-fuel mixture is provided at the top of the cylinder head 12 so as to project into the combustion chamber 15. Also, the cylinder head 1
The distributor 18 is disposed in the vicinity of the second exhaust camshaft 33, and the distributor 18 has a cylinder discrimination sensor for detecting a reference position signal generated at a predetermined rate as the exhaust camshaft 33 rotates. 42 are provided. The reference position signal is used for detecting the reference position of the crankshaft 14 and determining the cylinder.

Each spark plug 16 is connected to a distributor 18 via a plug cord or the like (not shown), and the high voltage output from the igniter 19 based on an ignition signal from the ECU 70 (described later) is The distributor 18 distributes the spark plugs 16 in synchronization with the crank angle.

The cylinder block 11 is also provided with a water temperature sensor 43 for detecting the temperature (cooling water temperature) THW of the cooling water flowing through the cooling water passage. The cylinder head 12 has an intake port 22 and an exhaust port 32, the intake passage 20 is connected to the intake port 22, and the exhaust passage 30 is connected to the exhaust port 32. An intake valve 21 is provided in the intake port 22 of the cylinder head 12, and an exhaust valve 31 is provided in the exhaust port 32.

Above the intake valve 21, an intake side camshaft 2 for driving the intake valve 21 to open and close.
3 is disposed, and an exhaust side cam shaft 33 for driving the exhaust valve 31 to open and close is disposed above the exhaust valve 31. An intake side timing pulley 27 and an exhaust side timing pulley 34 are attached to one end of each camshaft 23, 33.
7, 34 are connected to the crankshaft 14 via a timing belt 35.

Therefore, when the engine 10 is operating, the camshaft 2 is driven from the crankshaft 14 via the timing belt 35 and the timing pulleys 27 and 34.
The rotation driving force is transmitted to the camshafts 3 and 33, and each camshaft 2
The intake valve 21 and the exhaust valve 31 are opened / closed by rotating 3, 33. Each of these valves 21,
31 is the rotation of the crankshaft 14 and the piston 13
In synchronism with the vertical movement of the intake stroke, that is, the intake stroke, the compression stroke,
The engine 10 is driven at a predetermined opening / closing timing in synchronization with a series of four strokes in the engine 10 including an explosion / expansion stroke and an exhaust stroke.

Further, a cam angle sensor 44 is arranged near the intake side cam shaft 23. The cam angle sensor 44 is connected to the intake side cam shaft 23 by a magnetic rotor 44a and an electromagnetic pickup 44b. It consists of and. A plurality of teeth are formed on the outer circumference of the magnetic rotor 44a at equal angles, for example, at 120 ° CA in this embodiment. Then, for example, the compression T of the predetermined cylinder
Before DC, a pulsed cam angle signal (displacement timing signal) associated with the rotation of the intake camshaft 23 is detected between BTDC 90 ° and 30 °.

An air cleaner 24 is connected to the air intake side of the intake passage 20, and a throttle valve 26 that is opened / closed in conjunction with an accelerator pedal (not shown) is disposed in the middle of the intake passage 20. ing. Then, the intake air amount is adjusted by opening and closing the accelerator pedal.

A throttle sensor 4 for detecting the throttle opening TA is provided near the throttle valve 26.
5 are provided. Further, a surge tank 2 for suppressing intake pulsation is provided downstream of the throttle valve 26.
5 is formed. And, in the surge tank 25,
An intake pressure sensor 46 that detects the intake pressure in the surge tank 25 is provided. An injector 17 for supplying fuel to the combustion chamber 15 is arranged near the intake port 22 of each cylinder. Each injector 17 is an electromagnetic valve that is opened by energization, and each injector 17 is supplied with fuel that is pressure-fed from a fuel pump (not shown).

Therefore, when the engine 10 is operating,
The air filtered by the air cleaner 24 is taken into the intake passage 20, and at the same time as the intake of the air, fuel is injected from each injector 17 toward the intake port 22. As a result, the air-fuel mixture is generated in the intake port 22, and the air-fuel mixture is sucked into the combustion chamber 15 with the opening of the intake valve 21 that is opened in the intake stroke.

A catalytic converter 36 containing a three-way catalyst for purifying exhaust gas is arranged in the exhaust passage 30. An oxygen sensor 47 for detecting the oxygen concentration in the exhaust gas is arranged in the exhaust passage 30.

In the gasoline engine system of this embodiment, the variable valve timing mechanism 50 (hereinafter referred to as "VV") driven by hydraulic pressure is used to change the opening / closing timing of the intake valve 21 to change the valve overlap amount.
"T". ) Are arranged. This VVT50 is
Crankshaft 14 (intake side timing pulley 27)
Is a mechanism for continuously changing the valve timing of the intake valve 21 by changing the displacement angle of the intake side camshaft 23 with respect to the rotation of.

The system configuration of the VVT 50 will be described with reference to FIG. Here, FIG. 2 shows VVT5.
4 is an explanatory view showing a cross section near the intake side camshaft 23 in which 0 is arranged, and the entire control system of the VVT 50. FIG.

The control system of VVT50 is VVT5.
0, an oil control valve 80 (hereinafter referred to as “OCV”) that applies a driving force to the VVT 50, a cam angle sensor 44 that detects a cam angle signal, and a cam angle sensor 44.
An ECU 70 that drives and controls the OCV 80 based on input signals from various sensors such as

The VVT 50 is arranged between the intake side camshaft 23 and the intake side timing pulley 27,
The intake camshaft 23 is rotatably supported between the cylinder head 12 and the bearing cap 51. An intake side timing pulley 27 is rotatably mounted near the front end of the intake side camshaft 23, and an inner cap 52 has a hollow bolt 53 and a pin 54 at the front end of the intake side camshaft 23. It is attached so that it can rotate integrally.

A housing 56 having a cap 55 is attached to the intake side timing pulley 27 by a bolt 57 and a pin 58 so that the housing 56 can rotate integrally with the intake side timing pulley 27. The entire cap 52 is covered. Further, on the outer circumference of the intake side timing pulley 27, a large number of external teeth 27a for hanging the timing belt 35 are formed.

The intake side cam shaft 23 and the intake side timing pulley 27 are connected by a housing 56 and a ring gear 59 interposed between the inner cap 52. The ring gear 59 has a substantially annular shape and is housed in the space S surrounded by the intake side timing pulley 27, the housing 56, and the inner cap 52 so as to be reciprocally movable in the axial direction of the intake side camshaft 23. . Further, a large number of teeth 59 are provided on the inner and outer circumferences of the ring gear 59.
a and 59b are formed.

Correspondingly, a large number of teeth 52a are formed on the outer circumference of the inner cap 52 and the inner circumference of the housing 56.
56b is formed. These teeth 59a, 59b,
Both 52a and 56b are helical teeth whose tooth lines intersect the axis of the intake camshaft 23 at a predetermined angle. That is, the tooth 52a and the tooth 59a mesh with each other, and the tooth 56b and the tooth 59b mesh with each other to form a helical spline.

Due to these meshing, the rotation of the intake side timing pulley 27 is transmitted to the intake side camshaft 23 via the housing 56 and the inner cap 52. Also, each tooth 59a, 59b, 52a, 56
Since b is a helical tooth, when the ring gear 59 moves in the axial direction of the intake side camshaft 23, a twisting force is applied to the inner cap 52 and the housing 56, and the intake side camshaft 23 is attached to the intake side timing pulley 27. Move relative to.

In the space S, in order to move the ring gear 59 in the axial direction, a first hydraulic chamber 60 is provided at the tip end side of the ring gear 59, and a second hydraulic chamber 61 is provided at the base end side of the ring gear 59.
have. The bearing cap 51 has a first hydraulic pressure supply hole 51a and a second hydraulic pressure supply hole 51b. In addition, inside the intake side camshaft 23, the first
A first hydraulic pressure supply passage 62 that communicates the hydraulic pressure supply hole 51a and the first hydraulic pressure chamber 60, and a second hydraulic pressure supply passage 63 that communicates the second hydraulic pressure supply hole 51b and the second hydraulic pressure chamber 61 are formed. .

Then, the lubricating oil sucked up from the oil pan 65 by the hydraulic pump 64 is supplied to the respective hydraulic pressure supply holes 51a and 51b through the oil filter 66 with a predetermined pressure. In addition, each hydraulic pressure supply path 60, 6
In order to selectively supply the hydraulic pressure to the hydraulic pressure chambers 60 and 61 via the OCV 1, the OCV 8 is provided in the hydraulic pressure supply holes 51a and 51b.
0 is connected.

The OCV 80 is a 4-port directional control valve in which a plunger 83 driven by an electromagnetic actuator 81 and a coil spring 82 reciprocates a spool 84 in the axial direction to switch the flow direction of the lubricating oil. Then, the electromagnetic actuator 81
However, the opening degree is adjusted by the duty control, and the magnitude of the hydraulic pressure supplied to each hydraulic chamber 60, 61 is adjusted.

The OCV 80 casing 85 has a tank port 85t, an A port 85a, a B port 85b, and a reservoir port 85r. The tank port 85t is connected to the oil pan 65 via the hydraulic pump 64, and the A port 85a is connected to the first hydraulic pressure supply hole 5.
1a and B port 85b are connected to the second hydraulic pressure supply hole 51b. Further, the reservoir port 85r communicates with the oil pan 65.

The spool 84 is a cylindrical valve body, and
It has four lands 84a for sealing the flow of the lubricating oil between the two ports, and a passage 84b and a passage 84c for communicating the two ports and allowing the flow of the lubricating oil.

In the VVT 50 having these structures, O
When the CV 80 is drive-controlled and the spool 84 is moved to the left in the drawing, the passage 84b is in the tank port 85.
t and the A port 85a are communicated with each other, and the first hydraulic pressure supply hole 51a
Is supplied with lubricating oil. Then, the first hydraulic pressure supply hole 51a
The lubricating oil supplied to is supplied to the first hydraulic chamber 60 via the first hydraulic supply passage 62, and hydraulic pressure is applied to the tip side of the ring gear 59.

At the same time, the passage 84c connects the B port 85b and the reservoir port 85r, and the lubricating oil in the second hydraulic chamber 61 is supplied with the second hydraulic pressure supply passage 63, the second hydraulic pressure supply hole 51b, and the OCV 80. The oil is discharged to the oil pan 65 via the B port 85b and the reservoir port 85r.

Therefore, the ring gear 59 is moved while rotating to the base end side (right side in the drawing) by the hydraulic pressure applied to the tip end side, and the intake side cam shaft 23 is twisted via the inner cap 52. . As a result, the rotational phase (displacement angle) of the intake-side camshaft 23 relative to the intake-side timing pulley 27 (crankshaft 14) is changed (displaced), and the intake-side camshaft 23 changes from the most retarded angle displacement angle to the most advanced angle displacement angle. The intake valve 21
The valve opening timing of is advanced.

The intake valve 21 whose valve opening timing is advanced in this way is opened while the exhaust valve 31 is open, so that the intake valve 21 and the exhaust valve 31 are simultaneously opened. The lap period is extended. The movement of the ring gear 59 toward the base end side is restricted by the ring gear 59 contacting the intake side timing pulley 27, and when the ring gear 59 stops contacting the intake side timing pulley 27, the intake valve 21 moves. The valve opening timing is the earliest.

On the other hand, when the OCV 80 is drive-controlled and the spool 84 is moved to the right in the drawing, the passage 84
b connects the tank port 85t and the B port 85b,
Lubricating oil is supplied to the second hydraulic pressure supply hole 51b. And
The lubricating oil supplied to the second hydraulic pressure supply hole 51b is supplied to the second hydraulic pressure chamber 61 via the second hydraulic pressure supply passage 63, and hydraulic pressure is applied to the base end side of the ring gear 59.

At the same time, the passage 84c connects the A port 85a and the reservoir port 85r with each other, and the lubricating oil in the first hydraulic chamber 60 contains the first hydraulic pressure supply passage 62, the first hydraulic pressure supply hole 51a, and the OCV 80. The oil is discharged to the oil pan 65 via the A port 85a and the reservoir port 85r.

Therefore, the ring gear 59 is moved while being rotated to the front end side (the left side in the drawing) by the hydraulic pressure applied to the base end side, and the intake camshaft 23 is twisted in the opposite direction via the inner cap 52. Granted. As a result,
Intake side timing pulley 27 (crankshaft 14)
The rotational phase (displacement angle) of the intake-side camshaft 23 relative to is changed (displaced), the intake-side camshaft 23 is displaced from the most advanced displacement angle toward the most retarded displacement angle, and the opening timing of the intake valve 21 is changed. Is delayed.

By retarding the valve opening timing of the intake valve 21 in this manner, the valve overlap period in which the intake valve 21 and the exhaust valve 31 are simultaneously opened is reduced or eliminated. The movement of the ring gear 59 toward the tip side is restricted by the ring gear 59 coming into contact with the housing 56, and when the ring gear 59 comes into contact with the housing 56 and stops, the opening timing of the intake valve 21 becomes the latest. .

The valve timing of the intake valve 21 changed by the VVT 50 is the cam angle signal (displacement timing signal) output from the cam angle sensor 44 and the crank angle signal (reference timing signal) output from the crank angle sensor 40. ) And.

That is, for example, after the cam angle signal (displacement timing signal) is input to the ECU 70, the crank angle signal input first is recognized as the reference timing signal, and the reference timing is input after the displacement timing signal is input. The time required until a signal is input is measured using the engine speed NE. Then, the actual displacement angle VTB of the intake side camshaft 23 with respect to the crankshaft 14 is calculated by converting the time into a displacement angle using the relationship between the known time and the crank angle. Here, in this embodiment, the displacement timing signal is 12
Since it is detected every 0 ° CA, the intake side camshaft 23
The actual displacement angle VTB is calculated three times every one rotation of.

Next, the control system of the valve timing control device VC for an internal combustion engine according to this embodiment will be described with reference to the control block diagram shown in FIG. The control system of the valve timing control device VC of the internal combustion engine includes an electronic control unit 7
It is configured with 0 (hereinafter referred to as "ECU") as a core. Then, the ECU 70 controls the valve timing control means, the deviation storage means, the calibration means, the actual displacement angle calculation means,
Target displacement angle determination means, memory prohibition means, etc. are realized.

The ECU 70 stores various deviations, various control programs such as a learning control processing for executing a configuration based on the deviations, a valve timing control processing program including a learning control prohibition processing, and the intake side camshaft 23 corresponding to various conditions.
It has a ROM 71 storing a map for calculating the target displacement angle VTT. Further, the ECU 70 controls the RO
A CPU 72 that executes arithmetic processing based on a control program stored in M71, a RAM that temporarily stores the arithmetic result in the CPU 72, data input from each sensor, and the like.
73, a backup RAM 74 for holding various data such as deviations stored in the RAM 73 by the learning control process when the power supply is stopped.

The CPU 72, ROM 71, RAM
73 and the backup RAM 74 are the bidirectional bus 75.
And an input interface 76 and an output interface 77.

The input interface 76 includes a crank angle sensor 40, a cylinder discrimination sensor 42, a water temperature sensor 43,
A cam angle sensor 44, a throttle sensor 45, an intake pressure sensor 46, an oxygen sensor 47, etc. are connected. When the signal output from each sensor is an analog signal, it is output to the bidirectional bus 75 after being converted into a digital signal by an A / D converter (not shown).

External circuits such as the injector 17, the igniter 19, and the OCV 80 are connected to the output interface 77, and these external circuits are the CPU 72.
The operation is controlled based on the calculation result of the control program executed in.

Next, a valve timing control processing program in the valve timing control device VC for an internal combustion engine according to this embodiment having the above-mentioned structure will be described with reference to the flowchart shown in FIG.

Here, the valve timing control processing program learns the variation of each tooth of the rotor 44a forming the cam angle sensor 44, and does not perform the learning when the intake side camshaft 23 is being displaced. It is a program. In addition, "S" in the flow chart of each program indicates each step.

At S10, the engine speed NE and the intake pressure sensor 46 calculated by the ECU 70 based on the output signals from the crank angle sensor 40 and the cylinder discrimination sensor 42.
Based on the intake pressure PM detected by
The target displacement angle VTT is calculated from the map stored in. Next, in S20, the actual displacement angle VTB indicating the actual displacement angle of the intake side camshaft 23 with respect to the crankshaft 14 is calculated based on the reference timing signal (crank angle signal) and the displacement timing signal (cam angle signal). It

Here, a method of calculating the actual displacement angle VTB will be described with reference to FIG. FIG. 6 is a time chart showing the generation timing of the reference timing signal and the displacement timing signal. Further, the rotor 44a that constitutes the cam angle sensor 44 has three teeth formed for each 120 ° CA, and the first pulse signal, the second pulse signal, and the third pulse signal corresponding to each tooth. Occurs and is detected. Further, the crank angle signal that is first detected and input to the ECU 70 after the detected pulse signals are input to the ECU 70 becomes the reference timing signal.

First, after the displacement timing signal detected by the cam angle sensor 44 is input to the ECU 70, the crank angle signal (reference timing signal) first detected by the crank angle sensor 40 is input to the ECU 70. The signal interval (pulse signal interval) is measured as time using the engine speed NE. Next, by using the known relationship between the crank angle and the time (engine speed NE), the measured time is converted into the actual displacement angle VTB which is the cam angle with respect to the crank angle.

By the way, the rotors 44a, 40a forming the cam angle sensor 44 and the crank angle sensor 40 have a component tolerance, and the intervals of the equiangular teeth are not always equal. Further, a mounting error occurs when mounting both electromagnetic pickups 44b and 40b. Therefore, even when the intake-side camshaft 23 is rotating at a constant speed, the displacement timing signal should be generated (first pulse signal, second pulse signal, third pulse signal) at different times for each tooth. Therefore, the calculated actual displacement angle VTB also has variations as shown in FIG. Here, FIG. 7 shows the phase difference of the displacement timing signal with respect to the reference timing signal (actual displacement angle V
(TB) is a time chart schematically showing TB), and it is assumed that the reference timing signal always generates a constant value in order to simplify the explanation.

At S30, the calculated actual displacement angle V
The successive average actual displacement angle VTBA shown by the broken line in FIG. 7 is calculated by sequentially averaging TB for every three pulse signals of the corresponding displacement timing signal. This successive average actual displacement angle VTBA is an average value calculated based on the actual displacement angles VTB corresponding to the new three pulse signals each time a new displacement timing signal is generated, and the two previous actual displacement angles VTB. Therefore, it does not fluctuate significantly. Therefore, the intake side camshaft 2
It is suitable as a reference value for judging the qualitative displacement state of No. 3.

At S40, the change of the actual displacement angle VTB corresponding to the displacement timing signal sequentially detected by the cam angle sensor 44 is performed to determine whether or not the VVT 50 (the intake side camshaft 23) is being displaced. Judgment based on. Specifically, the absolute value of the difference between the previous actual displacement angle VTBO calculated this time and the actual displacement angle VTB calculated this time is a predetermined value a.
It is judged whether or not it is the following, and it is not judged depending on the successive average actual displacement angle VTBA in which the change is realized slowly. Therefore, when the pulse signal of 1 fluctuates greatly,
It is possible to quickly determine whether or not the intake side camshaft 23 is being displaced, without being affected by fluctuations in other pulse signals.

This state will be described with reference to FIGS. 10 and 11. FIG. 10 is a time chart showing the actual displacement of the intake side camshaft 23, and the vertical axis shows the actual displacement angle of the intake side camshaft 23 with respect to the crankshaft 14. In addition, FIG.
The state of displacement of the displacement angle of the intake side camshaft 23 shown in FIG. 4 is shown as the state of change of the actual displacement angle VTB calculated when detected by the cam angle sensor 44 and the crank angle sensor 40. The broken line shown in FIG. 11 is
The transition of the successive average actual displacement angle VTBA calculated based on the actual displacement angles VTB corresponding to the three pulse signals is shown.

As described above, the successive average actual displacement angle VTB
Since A is affected by the two actual displacement angles VTB calculated immediately before, even if one actual displacement angle VTB changes, the degree of change is small. Therefore, if it is attempted to determine whether or not the intake side camshaft 23 is being displaced by such a change, the predetermined value a must be reduced, and the displacement determination becomes strict. As a result, even though the intake camshaft 23 is not displaced, it is determined that the camshaft 23 is displaced, and the learning control process cannot be effectively executed. For this reason, the predetermined value “a” has to be set to a large value, and the displacement determination becomes uncomfortable. Further, since the successive average value of the three actual displacement angles VTB is used, the displacement cannot be determined until at least six actual displacement angles VTB have been calculated, and the displacement determination timing is delayed. .

On the other hand, when the actual displacement angle VTB corresponding to the displacement timing signal generated by the same tooth successively detected by the cam angle sensor 44 is used, the change in the actual displacement angle VTB is directly detected, and The displacement can be determined after calculating the three actual displacement angles VTB.
Further, since the judgment is made based on the actual displacement angle VTB corresponding to the displacement timing signal generated by the same tooth, it is not necessary to consider variations in the machining accuracy of the teeth in the rotor 44a, the mounting error of the cam angle sensor 44, etc., and the predetermined value a Can be made smaller and the judgment accuracy can be improved.

When it is determined that the absolute value of the difference between the old actual displacement angle VTBO and the actual displacement angle VTB calculated this time is equal to or less than the predetermined value a (S40: YES), the successive average actual displacement angle VTBA is calculated. The deviation of the actual displacement angle VTB with respect to is stored in the RAM 73 as the learned actual displacement angle GVTB. At this time, the learned actual displacement angle GVTB stored in the RAM 73 is calculated and stored for each actual displacement angle VTB calculated corresponding to the first to third pulse signals.

The state will be described with reference to FIG. FIG. 8 is an explanatory diagram showing the learned actual displacement angle GVTB corresponding to each actual displacement angle VTB when the successive average actual displacement angle VTBA is set to the reference value (0). As shown in the figure, a first pulse signal, a second pulse signal, generated every time the intake camshaft 23 makes one rotation, and
The learned actual displacement angle GVTB for each actual displacement angle VTB calculated corresponding to the third pulse signal is stored.

For example, the learned actual displacement angle GVTB with respect to the actual displacement angle VTB corresponding to the first pulse signal takes a negative value, and the actual displacement angle VT corresponding to the third pulse signal.
The learning actual displacement angle GVTB with respect to B has a positive value. The learned actual displacement angle GVTB for the actual displacement angle VTB corresponding to the first pulse signal calculated and stored previously is the learned actual displacement angle GVTB for the actual displacement angle VTB corresponding to the first pulse signal calculated this time. Is updated by storing.

On the other hand, when it is judged that the absolute value of the difference between the old actual displacement angle VTBO and the actual displacement angle VTB calculated this time is larger than the predetermined value a (S40: NO), it is calculated this time. The actual displacement angle VTB is replaced with the old actual displacement angle VTBO
(S60). That is, the actual displacement angle V
This is because the amount of displacement of TB is large, and therefore it is necessary to update the old actual displacement angle VTBO, which serves as a reference value when the degree of displacement of the intake camshaft 23 is determined next time in S40. Further, the intake side camshaft 23 does not store the deviation of the actual displacement angle VTB with respect to the sequential average actual displacement angle VTBA as the learned actual displacement angle GVTB in the RAM 73, and erroneous learning is avoided.

In subsequent S70, the actual displacement angle VTB is set to S5.
The calibration actual displacement angle VT is calculated by calibrating using the learned actual displacement angle GVTB calculated and stored at 0. This calibration is also executed for each actual displacement angle VTB calculated corresponding to each pulse signal.

Each actual displacement angle VTB is equal to each learned actual displacement angle G
The state of calibration by VTB will be described with reference to FIG. Here, FIG. 9 shows each learning actual displacement angle GVTB.
It is explanatory drawing which shows typically each actual displacement angle VTB after the calibration process by, ie, the calibration actual displacement angle VT. Note that the reference timing signal always generates a constant value in order to simplify the description as in FIG. 7.

As shown in the figure, the calibration actual displacement angle VT coincides with the successive average actual displacement angle VTBA, and the variation of the actual displacement angle VTB seen before the calibration is eliminated. As a result, the judgment value b used in the next step S80 can be made a small value.

In S80, it is determined whether the absolute value of the difference between the target displacement angle VTT and the calibration actual displacement angle VT is less than or equal to the determination value b. That is, it is determined whether or not the intake camshaft 23 has reached the target displacement angle. Then, the target displacement angle VTT and the calibration actual displacement angle VT
When it is determined that the absolute value of the difference between and is less than or equal to the determination value b (S80: YES), the process proceeds to S90.
In S90, the displacement angle in VVT 50, that is,
A holding control process for holding the displacement angle of the intake camshaft 23 at the current displacement angle is executed.

The holding control process will be briefly described. When the VVT 50 is displaced to the target displacement angle VTT, the duty ratio DV output to the OCV 80
T is switched from the duty ratio DVT that displaces the VVT 50 to the holding duty ratio DVTH that stops the displacement of the VVT 50 and holds the displacement angle. This holding duty ratio DVTH is the same as the spool 84 of the OCV 80.
Is predetermined as the duty ratio DVT corresponding to the position where the A port 85a and the B port 85b are closed, and is updated by learning to remove errors due to component tolerances, aging deterioration, and the like.

In this way, when the holding duty ratio DVTH is output to the OCV 80, the spool 84 of the OCV 80 is output.
Is duty-driven at a position to close the A port 85a and the B port 85b. As a result, the displacement angle of the VVT 50 is held at the displacement angle immediately before the holding control is started, that is, the target displacement angle VTT, without being displaced on the advance side or the retard side.

On the other hand, when it is determined that the absolute value of the difference between the target displacement angle VTT and the calibration actual displacement angle VT is larger than the determination value b (S80: NO), the step proceeds to S100. In S100, a feedback control process for displacing the displacement angle of the intake camshaft 23 to a target displacement angle is executed. That is, the control for displacing the intake camshaft 23 toward the target displacement angle VTT is executed by moving the spool 84 of the OCV 80 to the advance side or the retard side.

As described above in detail based on the embodiment,
The valve timing control device VC for the internal combustion engine according to the above-described embodiment includes the sequential average value of the three actual displacement angles VTB (sequential average actual displacement angle VTBA) corresponding to the first to third pulse signals detected by the cam angle sensor 44. ) With respect to each actual displacement angle VTB. In addition, based on each stored deviation, the corresponding actual displacement angle V
A configuration is provided in which TB is calibrated by the learned actual displacement angle GVTB.

Therefore, the VVT 50 can be controlled accurately without being affected by the mounting error of the cam angle sensor 44 or the like and the tolerance of the teeth formed on the rotor 44a or the like. As a result, it is possible to suppress variations in output characteristics and variations in emissions due to variations in the EGR amount inside the combustion chamber 15. Further, since the variation of the displacement timing signal detected by the cam angle sensor 44 is eliminated, the deviation does not always occur with respect to the target displacement angle VTT. Therefore, the OCV 80 is not always drive-controlled, and the durability and reliability of the OCV 80 can be improved.

Further, VVT50 (intake side camshaft 2
While 3) is displaced, the learning control prohibiting process for prohibiting the learning control process is executed. Therefore, it is possible to prevent erroneous learning without learning the displacement of the actual displacement angle VTB that appears during the transitional period when the intake side camshaft 23 is displaced, as the variation of the actual displacement angle VTB.

That is, the VVT 50 is a mechanism for changing the opening timing of the intake valve 21 by displacing the displacement angle (relative angle) of the intake side camshaft 23 with respect to the crankshaft 14. Therefore, if the variation of the actual displacement angle VTB is learned during the transition period when the intake camshaft 23 is displaced, the variation of the actual displacement angle VTB due to the displacement may be erroneously learned as a steady variation. .

Further, in determining whether or not the intake side camshaft 23 is in a transitional period in which the camshaft 23 is displaced, the cam angle sensor 44 sequentially detects the value without using the successive average actual displacement angle VTBA used in the learning control process. The configuration is such that the determination is made based on the displacement of the actual displacement angle VTB corresponding to the pulse signal. Therefore, as compared with the case where it is determined whether the intake side camshaft 23 is in the transitional period based on the successive average actual displacement angle VTBA, it is possible to quickly determine whether or not it is in the transitional period.

That is, the successive average actual displacement angle VTBA
Can be obtained, for example, by calculating the average of three actual displacement angles VTB that are sequentially calculated, as shown in the above embodiment. Therefore, the successive average actual displacement angle VTBA obtained each time has the influence of the immediately preceding two actual displacement angles VTB calculated based on the displacement timing signal generated with the rotation of the intake side camshaft 23 as shown in FIG. Will receive. As a result, the actual displacement angle VTB must be calculated 6 times in order to reflect only the rotation of the intake side camshaft 23 this time on the sequential average actual displacement angle VTBA, and the actual displacement angle VTB of the sequentially calculated actual displacement angle VTB must be calculated. It cannot fully reflect the changes.

On the other hand, the actual displacement angle V corresponding to the displacement timing signal generated by the same tooth of the rotor 44a
When judging the transitional period based on the change in TB, it is not necessary to consider the influence of other teeth, so the actual displacement angle VTB
Should be calculated four times. In this way, the transition period can be determined without being affected by other teeth, so that the state of changes in the actual displacement angle VTB that is sequentially calculated can be sufficiently reflected, and the determination accuracy can be improved. Along with being able to make decisions, it is possible to make decisions quickly.

The present invention can be variously modified and improved without departing from the spirit thereof. For example, in the above embodiment, the rotor having the three teeth is used as the rotor 44a that constitutes the cam angle sensor 44, but a rotor having another number of teeth may be used. Also,
In such a case, the sequential average actual displacement angle VTBA is calculated by the number of pulse signals according to the number of teeth formed on the rotor. In either case, crankshaft 1
This is because there is no change in that the displacement angle of the intake camshaft 23 with respect to 4 can be calculated.

In the above embodiment, the displacement timing signal is detected by the cam angle sensor 44 and the reference position signal is detected by the cylinder discrimination sensor 42. However, the cam angle sensor 44 and the cylinder discrimination sensor 42 are also used. It may be configured. In such a case, the number of sensor parts can be reduced.

As the VVT 50, a mechanism for changing the valve timing of the intake valve 21 by displacing the displacement angle of the intake side camshaft 23 with respect to the crankshaft 14 by hydraulic pressure is used. However, the crankshaft 1 can be driven by other driving means such as a step motor.
The displacement angle of the intake side camshaft 23 with respect to 4 may be displaced. That is, in the case of the VVT 50 configured to displace the displacement angle of the intake camshaft 23 with respect to the crankshaft 14, the actual displacement angle VTB is calculated based on the reference timing signal and the displacement timing signal, so the actual displacement angle VTB varies. This can occur.

In the above embodiment, the valve timing of the intake valve 21 is variably controlled to change the valve overlap period. However, the valve overlap period may be changed by variably controlling the valve timing of the exhaust valve 31 or by variably controlling the valve timing of the intake valve 21 and the exhaust valve 31.

In any case, the valve overlap period may be changed so that the desired engine characteristics can be obtained without change. The technical ideas other than the claims that can be understood from the above embodiments will be described below along with their effects.

(1) In the valve timing control device for an internal combustion engine according to any one of claims 1 to 3, the actual displacement angle calculation means includes the displacement timing signal and the reference timing signal. A valve timing control device for an internal combustion engine, wherein an actual displacement angle is calculated by converting an interval time of occurrence of the above into a rotation angle of a crankshaft.

With such a structure, the variable valve timing mechanism can be controlled based on the rotation angle of the crankshaft, which serves as the reference of the control timing in the internal combustion engine.

[0103]

As described above, according to the valve timing control device for an internal combustion engine according to the invention described in claim 1,
A configuration is provided in which the deviation of the actual displacement angle from the sequential average actual displacement angle is stored, and the variation of the actual displacement angle is learned by calibrating the actual displacement angle based on the stored deviation.

Therefore, it is possible to eliminate the influence of the variation of the actual displacement angle, and accordingly, the control accuracy of the variable valve timing mechanism can be improved. As a result, variations in the internal EGR amount in the combustion chamber are suppressed, desired output characteristics are obtained, and variations in emissions can be suppressed.

According to the valve timing control device for an internal combustion engine according to the second aspect of the present invention, the deviation of the actual displacement angle from the sequential average actual displacement angle is stored while the valve timing is being changed. It has a configuration that prohibits it.

Therefore, the variation of the actual displacement angle due to the change of the valve timing is not erroneously learned as the steady variation of the actual displacement angle. Further, according to the valve timing control device for an internal combustion engine according to the third aspect of the present invention, it is possible to quickly and accurately determine whether or not the valve timing is being changed. Learning can be suppressed.

[Brief description of drawings]

FIG. 1 is a conceptual configuration diagram showing a basic conceptual configuration of a valve timing control device for an internal combustion engine according to the present invention.

FIG. 2 is a system configuration diagram showing a schematic configuration of a gasoline engine system to which the present invention is applied.

FIG. 3 is a schematic configuration diagram of a variable valve timing mechanism system.

FIG. 4 is a control block diagram of a valve timing control device for an internal combustion engine.

FIG. 5 is a flowchart of a valve timing control processing program.

FIG. 6 is a time chart showing generation timings of a reference timing signal and a displacement timing signal.

FIG. 7 is a time chart schematically showing changes in the actual displacement angle VTB calculated based on the displacement timing signal and the reference timing signal.

FIG. 8 is a time chart schematically showing the deviation of the actual displacement angle VTB from the sequential average actual displacement angle VTBA.

FIG. 9: Learning actual displacement angle VTB Actual displacement angle GVTB
5 is a time chart schematically showing a change in the calibration actual displacement angle VT obtained by performing the calibration process by.

FIG. 10 is a time chart showing the actual displacement of the intake camshaft.

11 is an actual displacement angle VTB calculated based on a displacement timing signal and a reference timing signal corresponding to FIG.
Is a time chart that schematically shows changes in the.

[Explanation of symbols]

10 ... Engine, 14 ... Crankshaft, 15 ... Combustion chamber, 20 ... Intake passage, 21 ... Intake valve, 23 ... Intake side camshaft, 40 ... Crank angle sensor, 40a ... Rotor, 40b ... Pickup, 44 ... Cam angle sensor , 44
a ... Rotor, 44b ... Pickup, 46 ... Intake pressure sensor, 50 ... VVT, 70 ... ECU, 71 ... ROM, 7
3 ... RAM, M2 ... crankshaft, M3 ... intake side camshaft, M11 ... reference timing signal generating means, M
12 ... Variable valve timing mechanism, M14 ... displacement timing signal generating means, M15 ... deviation storage means, M16 ... calibration means, M18 ... valve timing control means, M19 ...
Deviation memory prohibition means, VC ... Valve timing control device for internal combustion engine.

Claims (3)

[Claims] 1. An intake-side camshaft and an exhaust-side camshaft which are rotationally driven in synchronization with a crankshaft of a rotating internal combustion engine, and are driven at predetermined timings in synchronization with rotations of the both camshafts. An intake valve and an exhaust valve that open and close an intake passage and an exhaust passage that communicate with the combustion chamber, operating state detection means for detecting the operating state of the internal combustion engine, and at predetermined crank angles with rotation of the crankshaft. A reference timing signal generating means for generating a reference timing signal; and a displacement angle of at least one of the intake side camshaft and the exhaust side camshaft with respect to the crankshaft, thereby displacing the intake valve or the exhaust valve. A variable bar that changes the timing of at least one valve. And a target displacement angle determining means for determining a target displacement angle of the camshaft on the side where the variable valve timing mechanism is disposed, according to an operating state of the internal combustion engine detected by the operating state detecting means, Based on the displacement timing signal and the reference timing signal, the displacement timing signal generating means generates a displacement timing signal at least once every one rotation of the camshaft on the side where the variable valve timing mechanism is installed, and the crankshaft. And an actual displacement angle calculating means for calculating an actual displacement angle of the camshaft on the side where the variable valve timing mechanism is disposed, and a sequential average displacement angle is calculated by sequentially averaging the actual displacement angle every predetermined number of times. A deviation record that stores the deviation of the actual displacement angle from the sequential average displacement angle. Means for calibrating the actual displacement angle calculated by the actual displacement angle calculating means using the deviation stored in the deviation storage means, and the actual displacement angle calibrated by the calibrating means, A valve timing control device for an internal combustion engine, comprising valve timing control means for controlling the variable valve timing mechanism so as to converge to a target displacement angle. 2. The valve timing control device for an internal combustion engine according to claim 1, wherein it is judged whether or not the valve timing is being changed by the variable valve timing mechanism, and the valve timing is changed. When it is determined that it is in the middle, a valve timing control of an internal combustion engine is provided, which is provided with a memory prohibiting unit that prohibits the deviation storing unit from storing the deviation of the actual displacement angle with respect to the successive average displacement angle. apparatus. 3. The valve timing control device for an internal combustion engine according to claim 2, wherein the memory prohibiting means is based on the actual displacement angle corresponding to the same displacement timing signal generated by the displacement timing signal generating means, A valve timing control device for an internal combustion engine, comprising: determining whether or not the valve timing is being changed by a variable valve timing mechanism.