JP2010223017A - Control device for variable valve timing mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inhibit the response speed of valve timing change by a variable-valve-timing mechanism from being different between banks in a V-type engine in which open actions of engine valves occur continuously in one bank. <P>SOLUTION: Operation quantity of the variable valve timing mechanism is corrected to an advancement side in a section where valve lift quantity of the engine valve increases and cam reaction force acts in a valve timing retardation direction, and operation quantity of the variable valve timing mechanism is corrected to a retardation side in a section where a valve lift quantity of the engine valve decreases and cam reaction force acts in a valve timing advancement direction. If a section where a valve lift quantity increases and a section where a valve lift quantity decreases overlap in different cylinders of the same bank, correction of the operation quantity is canceled. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a control device for a variable valve timing mechanism that makes a valve timing of an engine valve variable by making a relative rotational phase of a camshaft with respect to a crankshaft variable.

  Patent Document 1 discloses a direction in which the advance angle control is temporarily stopped and the cam reaction force does not prevent the advance angle when the cam reaction force accompanying the opening drive of the engine valve is generated in a direction that prevents the advance angle. A control device for a variable valve timing mechanism is disclosed that restarts the advance angle control when it becomes.

Japanese Patent Laying-Open No. 2005-075518

  By the way, in a V-type engine or a horizontally opposed engine having a variable valve timing mechanism in each bank, the opening operation of the engine valve whose valve timing is variable by the variable valve timing mechanism is not performed alternately in each bank. On the other hand, it may be performed continuously in the bank.

  As described above, when the opening drive is continuously performed in one bank, the opening operation is temporarily interrupted in the other bank, thereby the response speed of the valve timing change that is influenced by the cam reaction force. May become different between the two banks, and there may be a difference in valve timing between the two banks.

  The present invention has been made in view of the above problems, and in an engine in which the opening operation of the engine valve is continuously performed in one bank, the response speed of the valve timing change can be suppressed from being different between the banks. An object is to provide a control device.

  Therefore, in the present invention, the operation amount of the variable valve timing mechanism is corrected in the direction against the cam reaction force accompanying the opening operation of the engine valve.

  According to the above invention, since the response speed is suppressed from changing due to the influence of the cam reaction force, it is possible to suppress the response speed of the valve timing change from being different between banks.

1 is a system diagram of a V-type internal combustion engine in an embodiment of the present invention. It is a figure which shows the cylinder structure of each bank in embodiment of this invention. It is a perspective view which shows the variable lift mechanism in embodiment of this invention. It is sectional drawing of the variable lift mechanism in embodiment of this invention. It is sectional drawing which shows the variable valve timing mechanism in embodiment of this invention. It is sectional drawing which follows the AA line of FIG. 5, Comprising: It is a figure which shows a most retarded angle state. It is sectional drawing which follows the BB line of FIG. It is sectional drawing which follows the AA line of FIG. 5, Comprising: It is a figure which shows a most advanced angle state. It is a graph which shows the correlation with the magnetic flux density and magnetic field of a hysteresis material in the variable valve timing mechanism of embodiment of this invention. It is a partial expanded sectional view of FIG. It is the schematic diagram which developed the part of Drawing 10 in the shape of a straight line, and is a figure showing the flow of magnetic flux in the initial state (A) and when the hysteresis ring rotates (B). FIG. 5 is a diagram showing a change characteristic of a center phase of a valve lift amount, a valve operating angle, and a valve operating angle of an intake valve in the embodiment of the present invention. It is a flowchart which shows control of the variable valve timing mechanism in embodiment of this invention. It is a figure which shows the stroke order of each cylinder of the V type 8 cylinder engine in embodiment of this invention. It is a figure which shows the correlation with the lift state of the intake valve of each cylinder in embodiment of this invention, and the relative rotational phase of the camshaft in each bank. It is a figure which shows the change of the correction amount of the operation amount in case the intake stroke continues in one bank in embodiment of this invention. It is a figure which shows the change of the correction amount of the operation amount in the open period of the intake valve in embodiment of this invention.

Embodiments of the present invention will be described below.
FIG. 1 shows an internal combustion engine for a vehicle in the embodiment.
An internal combustion engine 101 shown in FIG. 1 is a V-type 8-cylinder engine including two banks (cylinder groups) 101a and 101b.

  In this V-type 8-cylinder engine, as shown in FIG. 2, the first bank 101a is composed of four cylinders of a first cylinder, a third cylinder, a fifth cylinder, and a seventh cylinder, and the second bank 101b is a second cylinder. , The fourth cylinder, the sixth cylinder, and the eighth cylinder, and the ignition is performed from the first cylinder → the eighth cylinder → the seventh cylinder → the third cylinder → the sixth cylinder → the fifth cylinder → the fourth cylinder → This is performed in the order of the second cylinder.

The internal combustion engine 101 is not limited to a V-type engine, and may be a horizontally opposed engine.
The combustion chamber 102 of each cylinder of the internal combustion engine 101 communicates with the atmosphere side via an intake duct 103, intake manifolds 104a and 104b, and an intake port 105.

  The intake port 102a of the combustion chamber 102 (cylinder) is opened and closed by an intake valve 106. When the intake valve 106 opens when the piston 107 descends, air is sucked into the combustion chamber 102.

  On the other hand, a fuel injection valve 108 is provided for each cylinder in each of the branch portions 140a and 140b of the intake manifolds 104a and 104b, which is an intake passage on the upstream side of the intake valve 106. Is injected into the combustion chamber 102 together with air.

The fuel injection valve 108 is arranged so that the spray is directed to the umbrella portion (intake port 102a) of the intake valve 106.
The fuel injection valve 108 may be an in-cylinder direct injection internal combustion engine that directly injects fuel into the combustion chamber 102.

  The fuel in the cylinder 102 is ignited and burned by spark ignition by the spark plug 109, and the explosive force generated thereby pushes down the piston 107, and the crankshaft 110 is rotationally driven by the push-down force.

  The exhaust port 102b of the combustion chamber 102 (cylinder) is opened and closed by an exhaust valve 111. When the exhaust valve 111 is opened when the piston 107 is raised, the exhaust gas in the combustion chamber 102 is discharged to the exhaust port 112. Is done.

  An intake camshaft 131 and an exhaust camshaft 132 to which the rotational driving force of the crankshaft 110 is transmitted are provided in each of the banks 101a and 101b, and the intake valve 106 and the exhaust valve 111 are respectively connected to the intake camshaft 131 and the exhaust cam. The shaft 132 is driven to open by rotating.

  Here, the exhaust valve 111 is driven to open at a constant maximum valve lift amount, valve operating angle, and valve timing by a cam 132a provided integrally with the exhaust camshaft 132.

  On the other hand, variable valve timing mechanisms 133a and 133b for continuously changing the relative rotational phase of the intake camshaft 131 with respect to the crankshaft 110 are provided on the intake camshafts 131 of the banks 101a and 101b, respectively. By making the relative rotational phase of the intake camshaft 131 variable by the timing mechanisms 133a and 133b, the center phase of the valve operating angle of the intake valve 106 changes continuously.

  In addition, the valve operating angle of the intake valve 106 is set to a valve lift amount (maximum) between the intake camshaft 131 and a swing cam 4 (described later) that contacts the valve lifter 106a of the intake valve 106 to drive the intake valve 106 open. A variable lift mechanism 134a, 134b is provided for each bank 101a, 101b for continuously changing the valve lift amount).

  The valve operating angle indicates the size of the opening period of the intake valve 106 as a crank angle, and the valve lift amount that the variable lift mechanisms 134a and 134b make variable is the opening degree of the intake valve 106. The maximum valve lift during the period.

  The exhaust port 112 is connected to the branch portions of the exhaust manifolds 113a and 113b, and the collective portions of the exhaust manifolds 113a and 113b are joined together and connected to the exhaust duct 114.

The exhaust duct 114 is provided with a catalytic converter 115 containing a catalytic device such as a three-way catalyst for purifying exhaust.
The intake duct 103 is provided with an electronic control throttle 116.

  Fuel injection by the fuel injection valve 108, ignition by the spark plug 109, opening characteristics (lift characteristics) of the intake valve 106 by the variable valve timing mechanisms 133a and 133b and variable lift mechanisms 134a and 134b, and throttle opening in the electronic control throttle 116 The degree is controlled by an ECM (Engine Control Module) 121.

  The ECM 121 includes a microcomputer, inputs signals from various sensors, performs arithmetic processing on the input signals according to a program stored in advance, calculates various operation amounts (control signals), The operation amount (control signal) is output.

  Examples of the various sensors include an accelerator opening sensor 122 that detects an accelerator opening ACC, a water temperature sensor 123 that detects a cooling water temperature TW (engine temperature) of the internal combustion engine 101, and a traveling speed of a vehicle on which the internal combustion engine 101 is mounted ( Vehicle speed) A vehicle speed sensor 124 for detecting VSP, a crank angle sensor 125 for outputting a unit crank angle signal POS for each rotation of the crankshaft 110 by a unit angle and a reference crank angle signal REF for each reference crank angle position. The air-fuel ratio sensors 126a and 126b, which are respectively disposed in the collection portions of the exhaust manifolds 113a and 113b of the bank and detect the air-fuel ratio AF of each bank based on the oxygen concentration in the exhaust, respectively, Detecting airflow sensor 127 and opening degree of electronic control throttle 116 A throttle opening sensor 128 for detecting the VO, such as pressure sensor 129 is provided for detecting the pressure (intake pipe pressure) PB within the intake passage of the electronic control throttle 116 downstream.

  The ECM 121 controls the engine rotation speed NE calculated based on the intake air flow rate QA detected by the air flow sensor 127 and the output signal from the crank angle sensor 125 in the control of fuel injection by the fuel injection valve 108. From these, the basic fuel injection pulse width TP is calculated.

  Further, the basic fuel injection pulse width TP is set so that the actual air / fuel ratio detected from the correction coefficient corresponding to the coolant temperature TW and the outputs of the air / fuel ratio sensors 126a and 126b approaches the target air / fuel ratio. The final fuel injection pulse width TI is calculated by correcting with a fuel ratio feedback correction coefficient or the like.

Then, the injection pulse signal having the fuel injection pulse width TI is individually output to the fuel injection valve 108 of each cylinder in synchronization with the intake stroke of each cylinder.
The fuel injection valve 108 opens for a time corresponding to the fuel injection pulse width TI, and injects an amount of fuel proportional to the valve opening time.

Each ignition plug 109 is directly attached with an ignition module 138 that incorporates an ignition coil and a power transistor that controls energization of the ignition coil.
The ECM 121 calculates ignition timing based on engine operating conditions (for example, engine load and engine speed NE), and starts energization of the ignition coil from the ignition time and energization time for obtaining ignition energy. The timing and energization cut-off timing are determined, the on / off of the power transistor is controlled by an ignition control signal corresponding to the energization start timing and energization cut-off timing, and spark ignition at the ignition timing is executed.

  Further, in the control of the variable valve timing mechanisms 133a and 133b and the variable lift mechanisms 134a and 134b, the target center phase (target valve timing) and the target valve lift amount are determined from the engine operating conditions (for example, target torque and engine speed NE). An operation amount is calculated and output so that the actual center phase / actual valve lift amount approaches the target.

  Further, in the control of the throttle opening TVO in the electronic control throttle 116, the target negative pressure is calculated from the engine operating conditions (for example, engine load and engine speed NE), and the actual intake pipe pressure detected by the pressure sensor 129 is calculated. The operation amount is calculated and output so that PB approaches the target negative pressure.

FIG. 3 is a perspective view showing the structure of the variable lift mechanisms 134a and 134b.
Above the intake valve 106, an intake camshaft 131 that is rotationally driven by the crankshaft 110 is supported by a cylinder head (not shown) so as to be rotatable along the cylinder row direction of each bank.

On the intake camshaft 131, a swing cam 4 that contacts the valve lifter 106a of the intake valve 106 and opens the intake valve 106 is externally fitted so as to be relatively rotatable.
The variable lift mechanisms 134 a and 134 b are provided between the intake camshaft 131 and the swing cam 4.

The variable valve timing mechanisms 133 a and 133 b are disposed at one end of the intake camshaft 131.
As shown in FIGS. 3 and 4, the variable lift mechanisms 134 a and 134 b include a circular drive cam 11 that is eccentrically fixed to the intake camshaft 131 and a ring that is externally fitted to the drive cam 11 so as to be relatively rotatable. Link 12, a control shaft 13 extending substantially parallel to the intake camshaft 131 in the direction of the cylinder row, a circular control cam 14 eccentrically fixed to the control shaft 13, and a relative rotation with respect to the control cam 14. The rocker arm 15 has one end connected to the tip of the ring-shaped link 12 and a rod-shaped link 16 connected to the other end of the rocker arm 15 and the swing cam 4. .

The control shaft 13 is rotationally driven via a link mechanism 18 by an electric motor 17 as an actuator.
As the electric motor 17, a DC motor or a brushless motor is used, but a hydraulic actuator can also be used as an actuator.

  The link mechanism 18 is provided integrally with the control shaft 13 and is provided integrally with a male screw 18a formed on the output shaft 17a of the motor 17, a female screw screwed into the male screw 18a, and the control shaft 13. Comprises a link arm 18c rotatably connected to the mover 18b.

  When the output shaft 17a of the motor 17 rotates, the mover 18b that is prevented from rotating translates in the axial direction of the output shaft 17a, and the link arm 18c is controlled in accordance with the translation of the mover 18b. By swinging about the shaft 13, the control shaft 13 integrated with the link arm 18c rotates.

  With the above configuration, when the intake camshaft 131 rotates in conjunction with the crankshaft 110, the ring-shaped link 12 moves substantially in translation through the drive cam 11, and the rocker arm 15 swings around the axis of the control cam 14. Then, the swing cam 4 swings through the rod-shaped link 16 and the intake valve 106 is driven to open.

  Further, by driving and controlling the motor 17 to change the rotation angle of the control shaft 13, the axial center position of the control cam 14 serving as the rocking center of the rocker arm 15 changes and the posture of the rocking cam 4 changes. .

As a result, the central phase of the valve operating angle of the intake valve 106 remains substantially constant, and the valve operating angle of the intake valve 106 changes continuously with the valve lift amount.
The movable angle range of the control shaft 13 is limited by a stopper (not shown), and one end of the movable angle range is a position where the valve lift amount is maximum, and the other end is the valve lift amount. When the control shaft 13 is rotated from one end of the movable angle range toward the other end, the valve lift amount gradually decreases, and conversely, from the other end of the movable angle range toward the one end. When the control shaft 13 is rotated, the valve lift is gradually increased.

  The ECM 121 detects the actual angle θ of the control shaft 13 with the angle sensor 135, and sets the operation amount of the motor 17 so that the actual angle θ approaches the target angle of the control shaft 13 corresponding to the target valve lift amount. Feedback control.

The variable lift mechanisms 134a and 134b may be configured so that the central phase of the valve operating angle changes simultaneously with the valve operating angle and the valve lift amount continuously changing.
The variable lift mechanisms 134a and 134b may be mechanisms that change the valve operating angle of the intake valve 106 (engine valve) together with the valve lift amount in accordance with the axial displacement of the control shaft.

5 to 8 show the structures of the variable valve timing mechanisms 133a and 133b.
As shown in FIGS. 5 to 8, the variable valve timing mechanisms 133 a and 133 b are assembled to the intake camshaft 131 and the front end portion of the intake camshaft 131 so as to be relatively rotatable as required. A drive ring 303 (drive rotator, second rotator) having a timing sprocket 302 linked to the crankshaft 110 via an outer periphery (not shown), and a front side of the drive ring 303 and the intake camshaft 131 ( 5 is arranged on the left side in FIG. 5, and an assembly angle operation mechanism 304 (assembly angle change mechanism) for operating the assembly angles of both 303 and 301, and further on the front side of the assembly angle operation mechanism 304. The operating force applying means 305 for driving the mechanism 304 and the cylinder head (not shown) of the internal combustion engine 101 and the front surface of the head cover are attached. Figure outside the cover covering the front and periphery region of assembling angle operating mechanism 304 and the operation force imparting unit 305 is provided with a.

  The drive ring 303 is formed in a short cylindrical shape having a step-like insertion hole 306, and the insertion hole 306 portion is connected to a front end portion of the intake camshaft 131. The first rotating body) is rotatably assembled.

  Then, on the front surface of the drive ring 303, in other words, on the surface opposite to the intake camshaft 131, as shown in FIG. 6, there are three radial grooves 308 (radial guides) having parallel side walls facing each other. ) Are formed along the radial direction of the drive ring 303.

  Further, as shown in FIG. 5, the driven shaft member 307 has a diameter-enlarged portion formed on the base-side outer periphery that abuts against the front end portion of the intake camshaft 131, and an outer peripheral surface on the front side of the enlarged-diameter portion. The three levers 309 projecting radially are integrally formed, and are coupled to the intake camshaft 131 by bolts 310 penetrating the shaft core portion.

  The base end of each link 311 is pivotally connected to each lever 309 by a pin 312, and a columnar protrusion 313 slidably engaged with each radial groove 308 is integrally formed at the tip of each link 311. Is formed.

  Since each link 311 is connected to the driven shaft member 307 via the pin 312 in a state where the protruding portion 313 is engaged with the corresponding radial groove 308, the distal end side of the link 311 receives an external force and receives the radial groove. When displaced along 308, the drive ring 303 and the driven shaft member 307 are relatively rotated by the action of the link 311 by a direction and an angle corresponding to the displacement of the protrusion 313.

  In addition, a housing hole 314 that opens to the front side in the axial direction is formed at the tip of each link 311, and the housing hole 314 has a spherical protrusion 316 a that engages with a spiral groove 315 (spiral guide) described later. An engagement pin 316 (rolling member) and a coil spring 317 that biases the engagement pin 316 forward (spiral groove 315 side) are accommodated.

  On the other hand, an intermediate rotating body 318 having a disk-like flange wall 318 a is rotatably supported via a bearing 331 in front of the protruding position of the lever 309 of the driven shaft member 307.

  The aforementioned spiral groove 315 having a semicircular cross section is formed on the rear surface side of the flange wall 318a of the intermediate rotating body 318, and the engagement pin 316 at the tip of each link 311 can freely roll in the spiral groove 315. Is engaged with the guide.

The spiral of the spiral groove 315 is formed so as to gradually reduce the diameter along the rotation direction of the drive ring 303.
Accordingly, in the state where the engagement pin 316 at the tip of each link 311 is engaged with the spiral groove 315, when the intermediate rotating body 318 rotates relative to the drive ring 303 in the phase lagging direction, the tip of the link 311 is in the radial direction. While being guided by the groove 308, it is guided in the spiral shape of the spiral groove 315 and moves radially inward, and conversely, when the intermediate rotating body 318 is relatively displaced in the phase advance direction, it moves radially outward.

  The assembly angle operation mechanism 304 includes the radial groove 308, the link 311, the protrusion 313, the engagement pin 316, the lever 309, the intermediate rotating body 318, the spiral groove 315, and the like of the drive ring 303 described above. .

  In the assembly angle operation mechanism 304, when a relative rotation operation force with respect to the intake camshaft 131 is input from the operation force applying means 305 to the intermediate rotating body 318, the operation force is applied to the spiral groove 315 and the engagement pin 316. The distal end of the link 311 is displaced in the radial direction through the engaging portion, and at this time, relative rotational force is transmitted to the drive link 303 and the driven shaft member 307 by the action of the link 311 and the lever 309.

  On the other hand, the operating force applying means 305 brakes the mainspring 319 for biasing the intermediate rotator 318 in the rotation direction of the drive ring 303 and the intermediate spring 318 for biasing in the direction opposite to the rotation direction of the drive ring 303. And a hysteresis brake 320 as a mechanism, and by appropriately controlling the braking force of the hysteresis brake 320 according to the operating state of the internal combustion engine 101, the intermediate rotating body 318 is rotated relative to the drive ring 303. Alternatively, the rotational position of both of them is maintained.

  The mainspring spring 319 has an outer peripheral end coupled to a cylindrical member 321 integrally attached to the drive ring 303, while an inner peripheral end is coupled to a cylindrical base of the intermediate rotating body 318. It is arranged in the space on the front side of the flange wall 318a of the intermediate rotating body 318.

  On the other hand, the hysteresis brake 320 is controlled in rotation by a bottomed cylindrical hysteresis ring 323 attached to the front end portion of the intermediate rotating body 318 via a retainer plate 322 and a cover (not shown) which is a non-rotating member. An electromagnetic coil 324 (actuator) as a magnetic field control means attached to the coil 101, and a coil yoke 325 which is a magnetic induction member for guiding the magnetism of the electromagnetic coil 324. The ECM 121 is controlled accordingly.

  As shown in FIG. 9, the hysteresis ring 323 is formed of a hysteresis material (semi-hard material) having a characteristic (magnetic hysteresis characteristic) in which the magnetic flux force changes with a phase lag with respect to a change in an external magnetic field. The side cylindrical wall 323a is subjected to a braking action by the coil yoke 325.

  The entire coil yoke 325 is formed in a substantially cylindrical shape so as to surround the electromagnetic coil 324, and the inner peripheral surface thereof is rotatably supported by the tip end portion of the driven shaft member 307 via the bearing 328.

  A pair of circumferential facing surfaces 326 and 327 are formed on the rear surface side (intermediate rotating body 318 side) of the coil yoke 325 so that the magnetic input / output portions face each other with a cylindrical gap.

  Further, as shown in FIG. 7, a plurality of concavities and convexities are continuously formed along the circumferential direction on both opposing surfaces 326 and 327 of the coil yoke 325, and the convex portions 326a and 327a of these concavities and convexities are formed as magnetic poles (Magnetic field generator).

  And the convex part 326a of one opposing surface 326 and the convex part 327a of the other opposing surface 327 are alternately arrange | positioned in the circumferential direction, and the convex parts 326a and 327a which the opposing surfaces 326 and 327 mutually adjoin are circumferential. It is off.

  Accordingly, a magnetic field having a direction inclined in the circumferential direction as shown in FIG. 10 is generated between the convex portions 326a and 327a adjacent to each other on the opposing surfaces 326 and 327 by the excitation of the electromagnetic coil 24.

A cylindrical wall 323a of the hysteresis ring 323 is interposed in a non-contact state in the gap between the opposing surfaces 326 and 327.
Here, the operating principle of the hysteresis brake 320 will be described with reference to FIG.

  11A shows a state in which a magnetic field is first applied to the hysteresis ring 323 (hysteresis material), and FIG. 11B shows a state in which the hysteresis ring 323 is displaced (rotated) from the state (A). Indicates the state.

  11A, the direction of the magnetic field between the opposing surfaces 326 and 327 of the coil yoke 325, in other words, the magnetic field from the convex portion 327a of the opposing surface 27 toward the convex portion 327a of the other opposing surface 326. A magnetic flux flows in the hysteresis ring 323 along the direction.

  From this state, when the hysteresis ring 323 is moved by receiving the external force F as shown in FIG. 11B, the hysteresis ring 323 is displaced in the external magnetic field. At this time, the magnetic flux inside the hysteresis ring 323 is The direction of the magnetic flux inside the hysteresis ring 323 has a phase delay, and the direction of the magnetic field between the opposing surfaces 326 and 327 is shifted (inclined).

  Accordingly, the flow of magnetic flux (magnetic lines) entering the hysteresis ring 323 from the convex portion 327a of the opposing surface 327 and the flow of magnetic flux (magnetic lines) from the hysteresis ring 323 toward the convex portion 326a of the other opposing surface 326 are distorted. An attractive force that corrects the distortion of the magnetic flux acts between the opposing surfaces 326 and 327 and the hysteresis ring 323, and the attractive force acts as a drag force F ′ that brakes the hysteresis ring 323.

  As described above, when the hysteresis ring 323 is displaced in the magnetic field between the opposing surfaces 326 and 327, the hysteresis brake 320 generates a braking force due to the deviation of the direction of the magnetic flux inside the hysteresis ring 323 and the direction of the magnetic field. To do.

  The braking force of the hysteresis brake 320 is the strength of the magnetic field, that is, the exciting current of the electromagnetic coil 324, regardless of the rotational speed of the hysteresis ring 323, that is, the relative speed between the opposing surfaces 326 and 327 and the hysteresis ring 323. It is a constant value that is approximately proportional to the size.

  The variable valve timing mechanisms 133a and 133b are configured as described above. When the excitation of the electromagnetic coil 324 of the hysteresis brake 320 is turned off, the intermediate rotating body 318 is moved to the drive ring 303 by the urging force of the mainspring spring 319. As shown in FIG. 6, the pin 316 is regulated at a position where it abuts against the outer peripheral end surface 315a of the spiral groove 315, and this position is controlled by the variable valve timing mechanisms 133a and 133b. This is the most retarded position of the relative rotational phase that can be changed.

  When the excitation of the electromagnetic coil 324 is turned on from this state, a braking force against the force of the mainspring spring 319 is applied to the intermediate rotating body 318, and the intermediate rotating body 318 rotates in the reverse direction with respect to the drive ring 303, As a result, the engaging pin 316 at the tip of the link 311 is guided into the spiral groove 315, whereby the tip of the link 311 is displaced along the radial groove 308, and the drive ring 303 and the driven shaft member 307 are acted upon by the link 11. The assembly angle is changed to the advance side.

  Then, when the exciting current of the electromagnetic coil 324 is increased to increase the braking force, the engaging pin 316 finally hits the inner peripheral side end face 315b of the spiral groove 315 as shown in FIG. This position is regulated by the position, and this position becomes the most advanced position of the relative rotation phase that can be changed on the mechanism of the variable valve timing mechanisms 133a and 133b.

  When the exciting current of the electromagnetic coil 324 is reduced from this state and the braking force is reduced, the intermediate rotating body 318 is rotated back in the forward direction by the urging force of the mainspring spring 319 and is linked by the induction of the engaging pin 316 by the spiral groove 315. 311 swings in the opposite direction, and the assembly angle of the drive ring 303 and the driven shaft member 307 is changed to the retard side.

  Thus, the relative rotational phase of the intake camshaft 131 (the center phase of the valve operating angle of the intake valve 105) with respect to the crankshaft 110 that is varied by the variable valve timing mechanisms 133a and 133b controls the excitation current value of the electromagnetic coil 324. Thus, the phase is arbitrarily changed by controlling the braking force of the hysteresis brake 320, and the phase can be maintained by the balance between the force of the mainspring spring 319 and the braking force of the hysteresis brake 320.

  Further, in the variable valve timing mechanisms 133a and 133b of the present embodiment, the lock pin 351 supported on the drive ring 303 side is fitted into the pin hole 352 provided in the intermediate rotating body 318 in which the spiral groove 315 is formed. As a result, the relative rotation of the intermediate rotator 318 with respect to the drive ring 303 is limited, and the position of the engagement pin 316 in the radial groove 308 is fixed, so that the lock pin 351 and the pin hole 352 are fitted. A lock mechanism is provided for locking to an intermediate phase determined by the position.

The intermediate phase is a relative rotational phase required at the time of starting on the advance side of the most retarded position.
The lock pin 351 is urged in a direction protruding toward the intermediate rotating body 318 by a spring force, and by an electromagnetic actuator 353 controlled by the ECM 121 (or a hydraulic actuator whose supply hydraulic pressure is controlled by an electromagnetic valve), It is pulled back toward the drive ring 303 against the spring force.

  The ECM 121 sets an operation amount (on-duty ratio) for controlling energization of the electromagnetic coil 324 of the hysteresis brake 320 to a feed forward amount based on the target center phase and a deviation (control error) between the target center phase and the actual center phase. ) And the feedback amount based on).

  The actual center phase is detected by measuring the angle from the reference angle position of the crankshaft 110 detected by the crank angle sensor 125 to the reference angle position of the intake camshaft 131 detected by the intake cam sensor 136. .

  As the variable valve timing mechanisms 133a and 133b, various known variable valve timing mechanisms can be employed. For example, as disclosed in Japanese Patent Laid-Open No. 2001-050063, a retarded-side hydraulic chamber is sandwiched between vanes. A variable valve timing mechanism that changes the relative rotation phase by controlling the hydraulic pressure in each hydraulic chamber by forming an advance side hydraulic chamber, and a mechanism that rotates the intake camshaft relative to the crankshaft using a gear In addition, a mechanism using an electric motor such as a DC motor or a brushless motor may be used as the actuator.

FIG. 12 shows changes in the opening characteristics of the intake valve 106 due to the variable valve timing mechanisms 133a and 133b and the variable lift mechanisms 134a and 134b.
As shown in FIG. 12, when the variable lift mechanisms 134a and 134b are operated, the valve operation of the intake valve 106 is maintained while the central phase of the valve operation angle of the intake valve 106 remains substantially constant, as shown by arrows (A). Both the angle and the valve lift vary continuously.

  On the other hand, when the variable valve timing mechanisms 133a and 133b are operated, the central phase of the valve operating angle of the intake valve 106 is maintained while the valve operating angle and the valve lift amount of the intake valve 106 remain constant, as shown by arrows (b). Changes.

Next, the control of the variable valve timing mechanisms 133a and 133b performed by the ECM 121 will be described in detail according to the flowchart of FIG.
The routine shown in the flowchart of FIG. 13 is executed for controlling the variable valve timing mechanism 133a in the first bank, and at the same time, is executed for controlling the variable valve timing mechanism 133b in the second bank. An operation amount for controlling the timing mechanism 133a and an operation amount for controlling the variable valve timing mechanism 133b are individually calculated.

  In the flowchart of FIG. 13, first, in step S501, it is determined whether or not an ignition switch 139, which is a main switch for operating / stopping the internal combustion engine 101, is in an ON state.

If the ignition switch 139 is OFF, the process proceeds to step S502, where it is determined whether the internal combustion engine 101 is stopped.
When the ignition switch is switched from the ON state to the OFF state and the operation of the internal combustion engine 101 is stopped, the process proceeds to step S503, and the crank angle when the internal combustion engine 101 is stopped in preparation for the restart of the internal combustion engine 101, Information such as the cylinder in which the next intake valve 105 is opened (the result of the last cylinder discrimination) is stored.

By storing the information, the start of fuel injection at the time of restart can be accelerated, and startability is improved.
In the next step S504, the value of the relative rotational phase of the intake camshaft 131 that is variable by the variable valve timing mechanisms 133a and 133b is stored when the engine is stopped.

  Here, if the lock mechanism is locked to the intermediate phase, the relative rotation phase stored in step S504 is the intermediate phase locked by the lock mechanism. If the lock mechanism fails to lock, the mainspring spring 319 is used. Since the intermediate rotator 318 rotates to the maximum in the engine rotation direction with respect to the drive ring 303 by the urging force, the most retarded angle position of the relative rotation phase is stored in step S504.

  On the other hand, if it is determined in step S501 that the ignition switch is in the ON state, the process proceeds to step S505, where it is determined whether the internal combustion engine 101 is rotating based on the signal of the crank angle sensor 125, and the internal combustion engine is determined. If 101 is rotating, the process proceeds to step S506.

On the other hand, when the internal combustion engine 101 is not rotating, the operation amount is not output to the variable valve timing mechanism 133 by ending this routine as it is.
That is, the drive of the variable valve timing mechanism 133 (the electromagnetic coil 324) is started after the start of the rotation of the internal combustion engine 101, whereby the drive control is started in a state where the relative rotation phase does not change. Thus, a high current is prevented from flowing through the electromagnetic coil 324.

In step S506, it is determined whether or not the first cylinder is determined.
The cylinder discrimination is a process of identifying a cylinder located at a reference piston position (for example, a reference crank angle position before top dead center), which is detected based on an output signal CAM from the intake cam sensor 136, and In step S503, the final result immediately before the engine stop of the cylinder discrimination is stored.

  If the first cylinder discrimination is not made, the process proceeds to step S507, and the cylinder in which the next intake valve 105 opened in step S503 is opened (the result of the last cylinder discrimination) is read. It is possible to determine whether is driven open.

  In step S508, an operation amount of the variable valve timing mechanisms 133a and 133b, that is, an energization control duty (operation amount) of the electromagnetic coil 324 of the hysteresis brake 320 is calculated.

  Specifically, as described above, the added value of the feed forward amount based on the target center phase and the feedback amount based on the deviation (control error) between the target center phase and the actual center phase is set as the control duty (operation Set as quantity).

  The calculation for the feedback based on the deviation (control error) is performed by, for example, a proportional operation, an integral operation, and a differential operation, but may be feedback control using a sliding mode.

  When the variable valve timing mechanisms 133a and 133b are of a hydraulic vane type, for example, the calculation for the feed forward is omitted, and the feedback is set as the duty (operation amount) as it is.

Here, it is assumed that the energization control duty (operation amount) increases the excitation current as the duty ratio increases and the relative rotation phase is advanced.
In step S509, by detecting the crank angle, together with the result of the cylinder discrimination, the cylinder that is in the intake stroke and the crank angle position during the intake stroke (open period of the intake valve 106) are determined.

In step S510 and subsequent steps (correction means), processing for correcting the operation amount calculated in step S508 in a direction against the cam reaction force is performed.
That is, while the intake valve 106 is lifted from the fully closed state to the maximum lift amount by the rotation of the intake camshaft 131, the lift amount is controlled against the urging force of the valve spring that urges the intake valve 106 in the fully closed direction. Therefore, the cam reaction force acts in a direction that retards the intake camshaft 131.

  Further, while the intake valve 106 subtracts the lift from the maximum lift amount and fully closes, the urging force of the valve spring acts in a direction that promotes the rotation of the intake camshaft 131, so that the intake camshaft 131 is advanced. The cam reaction force in the direction to be applied acts on the intake camshaft 131.

  When the cam reaction force acts on the intake camshaft 131, for example, in a transient state in which the relative rotational phase of the intake camshaft 131 is changed in the advance direction, the intake valve 106 is lifted from the fully closed state to the maximum lift amount. During this time, the advance angle change is hindered, and the response to the advance angle change is delayed. On the contrary, while the intake valve 106 subtracts the lift from the maximum lift amount until it is fully closed, the advance angle change is promoted. , The response of advance change becomes faster.

  Therefore, in step S510 and subsequent steps, in the generation region of the cam reaction force acting in the retarding direction, the operation amount is corrected to be increased to increase the excitation current (in other words, the driving force in the advancement direction) of the electromagnetic coil 324, On the other hand, in the region where the cam reaction force acting in the advance direction is generated, conversely, the manipulated variable is decreased and the excitation current of the electromagnetic coil 324 (in other words, the drive force in the advance direction) is reduced. The influence of the cam reaction force is suppressed, and the relative rotational phase of the intake camshaft 131 (the center phase of the intake valve 106) is stably changed toward the target.

  First, in step S510, the opening period of the intake valve 106 overlaps between different cylinders in the same bank, and there is a cam reaction force generation region acting in the retard direction and a cam reaction force generation region acting in the advance direction. It is determined whether or not it corresponds to the overlapping state.

  For example, in the first bank, in the angle range where the lift amount of the intake valve 106 of the third cylinder increases and changes, the lift amount of the intake valve 106 of the seventh cylinder in which the intake stroke is started immediately before that decreases. It is also an angular range.

  In the engine 101 of this embodiment, ignition is performed in the order of the first cylinder → the eighth cylinder → the seventh cylinder → the third cylinder → the sixth cylinder → the fifth cylinder → the fourth cylinder → the second cylinder. Correspondingly, as shown in FIGS. 14 and 15, the intake stroke of each cylinder is as follows: first cylinder → 8th cylinder → 7th cylinder → 3rd cylinder → 6th cylinder → 5th cylinder → 4th cylinder → 4th cylinder It is performed in the order of two cylinders, and the intake stroke of each cylinder is performed with a phase difference of 90 deg in crank angle.

  Therefore, as shown in FIG. 15, in the first bank, the intake stroke of the third cylinder follows the intake stroke of the seventh cylinder, the opening period of the intake valve 106 of the seventh cylinder, and the intake of the third cylinder The opening period of the valve 106 partially overlaps, and in the second bank, the intake stroke of the second cylinder follows the intake stroke of the fourth cylinder, the opening period of the intake valve 106 of the fourth cylinder, and the second cylinder The opening period of the intake valve 106 partially overlaps.

  More specifically, a period in which the valve lift amount of the intake valve 106 of the seventh cylinder is decreasing and a period in which the valve lift amount of the intake valve 106 of the third cylinder is increasing overlap, The period during which the valve lift amount of the intake valve 106 is decreasing overlaps with the period during which the valve lift amount of the intake valve 106 of the second cylinder is increasing.

  Here, since the intake valve 106 of the seventh cylinder and the intake valve 106 of the third cylinder are driven to open by the intake camshaft 131 on the same first bank side, the intake valve 106 of the seventh cylinder reduces the lift amount. In some cases, the lift operation generates a cam reaction force in a direction to advance the intake camshaft 131 on the first bank side, but at the same time, the intake valve 106 of the third cylinder increases the lift amount. In such a case, the lift operation generates a cam reaction force in a direction that reversely retards the intake camshaft 131 on the first bank side.

  Therefore, if the period during which the valve lift amount of the intake valve 106 of the seventh cylinder is decreasing overlaps with the period during which the valve lift amount of the intake valve 106 of the third cylinder is increasing, during this overlap period, the advance When the cam reaction force in the angular direction and the cam reaction force in the retard direction are canceled out, the cam reaction force that actually acts on the intake camshaft 131 is negligibly small, and the intake valve 106 is not opening. Therefore, it is not necessary to correct the operation amount to counter the cam reaction force.

  Also in the fourth cylinder and the second cylinder in the second bank, a period in which the valve lift amount of the intake valve 106 of the fourth cylinder is decreasing, and a period in which the valve lift amount of the intake valve 106 of the second cylinder is increasing. During the overlap period, the cam reaction force in the advance angle direction and the cam reaction force in the retard angle direction cancel each other, and the cam reaction force actually acting on the intake camshaft 131 causes the intake valve 106 to open. This is equivalent to the case where there is no operation, and the correction of the operation amount for resisting the cam reaction force is unnecessary.

  Therefore, whether the cam reaction force in the advance direction and the cam reaction force in the retard direction are offset is determined based on whether the intake valve 106 is closed at the closing timing IVC and the opening timing IVO in the cylinder where the intake stroke continues. Judging from.

  Specifically, the crank angle position advanced by half the valve operating angle from the central phase of the valve operating angle at that time is the opening timing IVO of the intake valve 106, and is delayed by half the valve operating angle. It can be determined whether or not the angled crank angle position is the closing timing IVC of the intake valve 106 and whether or not the intake stroke of the cylinder in which the intake stroke is continuous is based on the result of cylinder discrimination.

  The opening timing of the intake valve 106 in the cylinder that will be in the intake stroke later in the two cylinders (seventh and third cylinders in the first bank, and fourth and second cylinders in the second bank) in which the intake stroke continues. From the IVO until the closing timing IVO of the intake valve 106 in the cylinder that is first in the intake stroke, the angle at which the generation region of the cam reaction force acting in the retard direction and the generation region of the cam reaction force acting in the advance direction overlap Detect as an interval.

  If it is determined in step S510 that the current angular position corresponds to an angular region in which the cam reaction force in the advance angle direction and the cam reaction force in the retard angle direction cancel each other, steps S511 to S51 are performed. By bypassing S515 and proceeding to step S516, the operation amount calculated in step S508 is directly output to the drive circuit of the electromagnetic coil 324 without correction.

Therefore, as shown in FIG. 16, in the overlap period, the correction amount is set to zero, and the correction of the operation amount for resisting the cam reaction force is cancelled.
On the other hand, if it is determined in step S510 that the current angular position does not fall within the angular range where the cam reaction force in the advance angle direction and the cam reaction force in the retard angle direction cancel each other, the process proceeds to step S511. .

  In step S511, the angular range in which the cam reaction force acts in the direction that retards the intake camshaft 131, in other words, the angular range in which the lift amount of the intake valve 106 increases and changes in any of the cylinders in the same bank. Determine if it exists.

The angle region in which the lift amount increases and changes is from the opening timing IVO of the intake valve 106 to the timing MLT at which the maximum lift amount is reached, and is the maximum lift amount at the center of the valve opening period.
However, since the determination in step S510 is passed, even in an angular region where the cam reaction force acts in the retarding direction in a certain cylinder, the cam reaction force acts in the advance direction in other cylinders. If there is, it is excluded.

  If it is determined in step S511 that the cam reaction force is in an angle range that acts in the direction of retarding the intake camshaft 131, the process proceeds to step S512, and the force acting in the direction of advancement against the cam reaction force. In order to increase the operation amount, an increase correction amount for increasing the excitation current of the electromagnetic coil 324 (in other words, the driving force in the advance direction) is set.

  When the variable valve timing mechanisms 133a and 133 are hydraulic vane type, in step 512, the hydraulic pressure in the advance side hydraulic chamber is increased, and the operation amount is corrected so that the vane is driven toward the advance side.

Here, the increase correction amount can be given as a constant value in an angle region where the lift amount increases and changes.
Further, the cam reaction force acting in the retarding direction increases with the increase in the lift amount from the start of opening of the intake valve 106 to a maximum value, and decreases as it approaches the peak of the cam peak (maximum lift amount). Therefore, as shown in FIGS. 16 and 17, the increase correction amount can be changed so as to correspond to the change in the magnitude of the cam reaction force.

  That is, the increase correction amount whose initial value is zero is gradually increased from the opening timing IVO of the intake valve 106 according to the crank angle rotation, and is intermediate between the opening timing IVO and the timing MLT (center phase position) at which the maximum lift amount is reached. The maximum correction amount is gradually decreased and then the increase correction amount is gradually decreased as the maximum lift amount timing MLT is approached, and the increase correction amount is returned to zero at the maximum lift amount timing MLT.

  In the present embodiment, the maximum valve lift amount is changed by the variable lift mechanisms 134a and 134b. The larger the maximum valve lift amount, the larger the force acting in the direction of retarding the intake camshaft 131. The larger the maximum valve lift amount that can be changed by the lift mechanisms 134a and 134b, the larger the increase correction amount (which increases the operation amount to be increased) can be set.

  If it is determined in step S511 that the cam reaction force is not in an angular range in which the intake camshaft 131 is retarded, the process proceeds to step S513 and the cam reaction force is advanced in the direction in which the intake camshaft 131 is advanced. It is determined whether or not the angle range in which the valve operates, in other words, the angle range in which the lift amount of the intake valve 106 is decreasing in any of the cylinders in the same bank.

  The angle range in which the lift amount decreases is from the timing MLT when the valve lift amount of the intake valve 106 becomes the maximum lift amount to the closing timing IVC of the intake valve 106, and becomes the maximum lift amount at the center of the valve opening period. And

  However, since the determination in step S510 has been passed, even if the cam reaction force acts in the advance direction in a certain cylinder, the cam reaction force acts in the retard direction in another cylinder. If there is, it is excluded.

  If it is determined in step S513 that the cam reaction force is in an angle range that acts in the direction in which the intake camshaft 131 is advanced, the process proceeds to step S514, and the operation amount decrease correction is performed so as to weaken the force acting in the advance direction Then, a decrease correction amount for reducing the excitation current of the electromagnetic coil 324 (in other words, the driving force in the advance direction) is set.

In other words, by reducing the exciting current of the electromagnetic coil 324, it is driven in the retard direction by the urging force of the mainspring spring 319, and resists the cam reaction force acting in the advance direction.
In the case where the variable valve timing mechanisms 133a and 133 are of the hydraulic vane type, in step 514, the operation amount is corrected so that the oil pressure in the retard side hydraulic chamber is increased and the vane is driven toward the retard side.

Here, the decrease correction amount can be given as a constant value in an angle region where the lift amount decreases and changes.
Further, the cam reaction force acting in the advance direction increases from the state of the maximum lift amount as the lift amount decreases and then decreases as it approaches the fully closed state, so as shown in FIGS. 16 and 17, The reduction correction amount can be changed to correspond to the change in the magnitude of the cam reaction force.

  That is, the absolute value of the decrease correction amount whose initial value is zero is gradually increased according to the crank angle rotation from the timing MLT (center phase position) at which the maximum lift amount is reached, and the timing MLT and the closing timing IVC at which the maximum lift amount is reached. The absolute value of the decrease correction amount is gradually decreased as the timing approaches the closing timing IVC, and the decrease correction amount is returned to zero at the closing timing IVC.

  In the present embodiment, the maximum valve lift amount is changed by the variable lift mechanisms 134a and 134b. The larger the maximum valve lift amount, the larger the force acting in the direction in which the intake camshaft 131 is advanced. The larger the maximum valve lift amount that can be changed by the lift mechanisms 134a and 134b, the larger the reduction correction amount (which increases the operation amount to reduce the operation amount) can be set.

  As described above, the correction of the operation amount is canceled in the overlap period. However, as shown in FIG. 16, in the lift increase section before the overlap period, the operation amount is corrected in the advance direction. An increase correction amount is set, and in the lift decrease section immediately after the overlap period, a decrease correction amount for correcting the operation amount in the retard direction is set.

When the correction amount is set in step S512 or step S514, the process proceeds to step S515, and the operation amount calculated in step S508 is corrected and set with the correction amount.
Specifically, when the increase correction amount is set, the duty (excitation current) is increased by the increase correction amount, and when the decrease correction amount is set, the duty (by the decrease correction amount is set). Decrease the excitation current.

  On the other hand, if it is determined in step S513 that the cam reaction force is not in an angular range in which the intake camshaft 131 is advanced, that is, it is not the open period of the intake valve 106 in any cylinder in the same bank. In this case, by bypassing Steps S512, S514, and S515 and proceeding to Step S516, the operation amount correction is canceled and the operation amount calculated in Step S508 is output.

In step S516, the excitation current of the electromagnetic coil 324 is controlled based on the operation amount (duty) determined by the above processing.
As described above, if the operation amount of the variable valve timing mechanisms 133a and 133b is corrected so as to resist the cam reaction force, the relative rotation phase of the intake camshaft 131 is advanced or retarded by the action of the cam reaction force. Fluctuation in the direction is suppressed.

  In the V-type 8-cylinder engine of the present embodiment, as described above, cylinders that alternately perform the intake stroke between the banks do not occur, but the intake stroke continuously occurs in one bank as shown in FIG. In some cases, while the intake stroke is continuously performed in one bank, the opening of the intake valve 106 is not performed in the other bank.

  Therefore, as indicated by a solid line in FIG. 15, the response speed of the relative rotational phase differs between the two banks, and the relative rotational phase between the two banks, that is, the central phase of the valve operating angle of the intake valve 106 (valve (Timing) becomes different, and torque variation and combustion variation occur between banks.

  However, in this embodiment, by correcting the operation amount in the direction against the cam reaction force, the influence of the cam reaction force is suppressed, and the change characteristic indicated by the solid line in FIG. 15 approaches the change characteristic indicated by the dotted line. Even if the intake stroke is continuously performed in one bank, it is possible to suppress the difference in response speed of the relative rotational phase between the banks, and the center phase of the valve operating angle of the intake valve 106 is different between both banks. This can be suppressed.

  Therefore, it is possible to suppress torque variation and combustion variation between banks in a transient state in which the relative rotation phase of the intake camshaft 131 is changed, and it is possible to improve drivability in the transient state.

  In the above embodiment, the operation amount is always corrected for the opening operation of the intake valve. However, the operation amount is corrected in the direction against the cam reaction force only at the time of transition in which the relative rotation phase is changed. Can do.

  Also, the cam reaction force that is actually generated is expressed as the absolute value of the increase correction amount that corrects the operation amount when the lift amount increases and the absolute value of the decrease correction amount that corrects the operation amount when the lift amount decreases. Corresponding to the difference, the same lift amount can be made different.

  Further, it is possible to detect a change in the relative rotational phase when the operation amount is corrected, correct the correction amount based on the detection result, store the correction result, and perform learning used for the subsequent correction. .

  In this embodiment, the camshaft whose relative rotational phase is changed by the variable valve timing mechanism is the intake camshaft. However, the camshaft is a mechanism for changing the relative rotational phase of the exhaust camshaft, and the valve operation of the exhaust valve. A configuration in which the center phase of the corner is variable may be employed.

  In addition, the camshaft relative rotational phase fluctuations affected by the cam reaction force increase as the engine rotates at low speeds, so the correction must be canceled in the high speed range where the relative rotational phase fluctuations are within the allowable range. Can do.

Here, technical ideas other than the claims that can be grasped from the above embodiment will be described together with effects.
(A) In the control apparatus for a variable valve timing mechanism according to claim 2,
A control apparatus for a variable valve timing mechanism, wherein the correction means cancels correction in a region where an increase change section of a valve lift amount and a decrease change section of a valve lift amount overlap in the same bank.

According to the above invention, in the section where the cam reaction force acting in the advance direction and the cam reaction force acting in the retard direction cancel each other, unnecessary correction is not made, and the relative rotational phase of the camshaft is corrected. Can be suppressed.
(B) In the control device for a variable valve timing mechanism according to claim 3,
A control device for a variable valve timing mechanism, wherein the correction means corrects the operation amount more as the maximum valve lift amount that is variable by the variable lift mechanism is larger.

  According to the above invention, when the maximum valve lift amount is large and the cam reaction force is large, the correction amount can be increased to resist the actually generated cam reaction force.

  DESCRIPTION OF SYMBOLS 101 ... Internal combustion engine, 106 ... Intake valve, 110 ... Crankshaft, 111 ... Exhaust valve, 121 ... ECM (engine control module), 125 ... Crank angle sensor, 131 ... Intake camshaft, 133a, 133b ... Variable valve timing Mechanism, 134a, 134b ... Variable lift mechanism, 135 ... Angle sensor, 136 ... Cam sensor

Claims (3)

The engine is provided with each bank of the internal combustion engine having two banks, and the opening order of the engine valves between the cylinders continues in one bank, and the relative rotational phase of the camshaft with respect to the crankshaft is variable. A control device for a variable valve timing mechanism that makes the valve timing of a valve variable,
A control apparatus for a variable valve timing mechanism, comprising: a correction unit that corrects an operation amount of the variable valve timing mechanism in a direction against a cam reaction force accompanying an opening operation of the engine valve.   The correction means corrects the operation amount in a direction in which the relative rotation phase is advanced in an increasing change section of the valve lift amount during the engine valve open period, and the valve lift during the engine valve open period. 2. The control device for a variable valve timing mechanism according to claim 1, wherein the manipulated variable is corrected in a direction in which the relative rotational phase is retarded in the variable change section. The internal combustion engine includes a variable lift mechanism that makes the maximum valve lift amount of the engine valve variable,
The control device for a variable valve timing mechanism according to claim 1 or 2, wherein the correction means changes the correction amount of the operation amount in accordance with a maximum valve lift amount that is variable by the variable lift mechanism.

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