JP5584797B1 - Valve timing control device for internal combustion engine - Google Patents

Abstract

A valve timing control device for an internal combustion engine capable of reliably releasing a lock pin of a lock mechanism in a lube timing changing mechanism in any case.
A lock pin and a lock hole are provided while applying a biasing force to rotate relative to a second rotating body by hydraulic oil supplied based on rotation of an output shaft of an internal combustion engine when unlocking by a lock mechanism. A valve timing control device for an internal combustion engine that releases the lock by applying an urging force by hydraulic oil to the lock pin engaged with the lock hole so as to release the engagement of the lock, and detects the lock by the lock mechanism In this case, the lock is released in a state where the output of the internal combustion engine is reduced and the hydraulic oil pressure is reduced.
[Selection] Figure 4

Description

  The present invention relates to a valve timing control device for controlling the opening / closing timing of at least one of an intake valve and an exhaust valve of an internal combustion engine.

  In an internal combustion engine mounted on a vehicle, in order to improve fuel consumption, output, and exhaust properties, at least one of an intake valve provided in the intake hole of the internal combustion engine and an exhaust valve provided in the exhaust hole There is provided a valve timing control device for controlling the opening / closing timing of the valve, so-called valve timing, in accordance with the operating state of the internal combustion engine. The valve timing control device includes a rotation phase changing mechanism that can change the relative rotation phase of the camshaft with respect to the output shaft of the internal combustion engine, and a lock mechanism that holds the relative rotation phase at a predetermined phase. A valve timing changing mechanism, and an oil control valve (hereinafter referred to as OCV) that controls hydraulic oil that drives the valve timing changing mechanism.

  The rotation phase changing mechanism in the valve timing changing mechanism includes an advance hydraulic chamber and a retard hydraulic chamber, and supplies hydraulic oil having hydraulic pressure generated by rotation of the internal combustion engine from the OCV to the advance hydraulic chamber or By supplying to the retarding hydraulic chamber, the relative rotational phase of the camshaft with respect to the output shaft of the internal combustion engine can be changed. In addition, the lock mechanism in the valve timing changing mechanism is difficult to hold the vane rotor of the rotational phase changing mechanism at a predetermined position because the hydraulic oil pressure is insufficient when starting the internal combustion engine. This is for locking the position of the rotor to a predetermined position at the time of starting, for example, the most advanced position.

  The lock mechanism described above includes a lock pin provided in a part of the vane in the rotation phase changing mechanism and a lock hole provided in a storage chamber for storing the vane rotor. The lock pin is separated from the vane by the biasing force of the spring. The vane rotor is configured to be locked at a predetermined position by protruding and engaging with the lock hole. On the other hand, when the operation of the internal combustion engine is started and the hydraulic pressure of the hydraulic oil exceeds a predetermined pressure, the lock pin is pushed back into the vane against the urging force of the spring by the hydraulic pressure, and the lock pin and the lock hole are engaged. Is released.

  According to the valve timing changing mechanism having such a lock mechanism, the rotation of the vane rotor can be restricted even when the hydraulic pressure of the hydraulic oil cannot be sufficiently ensured, such as when the internal combustion engine is started. It is possible to avoid an unstable operation of the control device. However, if a force that moves the vane to the retarded side acts before the lock is released due to some factor, the contact pressure at the contact portion between the lock pin and the lock hole increases, thereby fixing the lock pin to the lock hole. Therefore, there is a possibility that the operation of accommodating the lock pin in the vane during the unlocking operation is hindered.

  If the lock pin of the lock mechanism sticks to the lock hole in this way and the unlocking operation is obstructed, the phase change control cannot be started immediately and the valve timing cannot be changed. If the phase change control is started in a state where the locked state by the mechanism is not completely released and the hydraulic pressure of the hydraulic oil is increased, the lock pin may be damaged or deformed.

  Therefore, in the past, by changing the drive duty of the rotation phase change mechanism portion by OCV periodically with respect to the lock mechanism, the relative position of the lock hole and the lock pin is changed, and the lock pin and the lock hole are fixed and unlocked. A valve timing control device for an internal combustion engine in which the mechanism is unlocked has been proposed (for example, see Patent Document 1). Conventionally, the valve timing control of the internal combustion engine in which the driving duty by the OCV is controlled so that the unlocking operation is performed at the timing when the lock hole and the lock pin are not joined is adjusted by adjusting the control start timing of the unlocking operation. An apparatus has been proposed (see, for example, Patent Document 2).

JP 2009-133263 A Japanese Patent No. 4883244

  In the case of the conventional valve timing control device for an internal combustion engine described in Patent Document 1, the reverse torque due to the rotational inertia generated with respect to the cam rotation direction is the same as the rotation direction corresponding to the retard side of the vane. Therefore, even if the drive duty of the rotation phase changing mechanism is 0 [%], the lock pin is locked in the lock hole when the reverse torque due to the rotation inertia is large with respect to the advance oil pressure supplied to the advance hydraulic chamber. In contrast, a state where contact occurs on the retarded angle side occurs. For this reason, when the vane operates on the retard side when the drive duty is 100 [%], contact with the retard hole on the retard side further increases, and the lock cannot be released. was there.

  Further, in the case of the conventional valve timing control device for an internal combustion engine described in Patent Document 2, when the crank angle is a predetermined angle, the release of the lock pin is started. Due to variations in the accuracy of the crank angle sensor, variations in the actuator from when the drive duty is applied to the OCV until the hydraulic pressure is supplied, and variations in the flow resistance of the hydraulic oil passage itself, the predetermined crank angle is affected. There was a problem that it was difficult to match.

  The present invention has been made to solve the above-described problems in the valve timing control device of a conventional internal combustion engine. In any case, the lock pin of the lock mechanism in the valve timing changing mechanism can be released. It is another object of the present invention to provide a valve timing control device for an internal combustion engine that can be reliably performed.

The valve timing control device according to the present invention comprises:
A first rotating body connected to the output shaft of the internal combustion engine;
Connected to a camshaft that opens and closes an intake valve or an exhaust valve of the internal combustion engine, shares an axis with the first rotating body and is housed in the first rotating body, and is attached to the first rotating body. A second rotating body configured to be relatively rotatable around the axis,
A lock hole formed in one of the first rotating body and the second rotating body, and the other of the first rotating body and the second rotating body provided on the other of the axial center. A lock pin formed so as to be movable in the same direction as the extending direction, and the lock pin moves to the lock hole side and engages with the lock hole, whereby the second rotating member with respect to the first rotating body is engaged. and a lock mechanism capable of locking the rotation of the rotating body,
While releasing the lock by the lock mechanism, while applying a biasing force to rotate the second rotating body relative to the second rotating body by hydraulic oil supplied from an oil control valve based on rotation of the output shaft of the internal combustion engine, Applying a biasing force by the hydraulic oil to the lock pin engaged with the lock hole so as to release the engagement between the lock pin and the lock hole, to release the lock, and to A valve timing control device for an internal combustion engine configured to control valve timing for opening and closing the intake valve or the exhaust valve by rotating relative to a first rotating body ;
Oil control valve drive determining means for determining whether or not the operating state of the internal combustion engine is in a state of controlling the oil control valve to control the valve timing;
A lock release determination means for determining whether or not the lock is released based on an actual advance angle amount and a target advance angle amount of the intake valve or the exhaust valve;
With
When the oil control valve drive determining means determines that the valve timing is being controlled and the unlock determination means determines that the lock has not been released , the output of the internal combustion engine is reduced. In the state where the hydraulic pressure of the hydraulic oil is reduced, the lock is released.
It is characterized by this.

  According to the valve timing control apparatus for an internal combustion engine according to the present invention, when the lock by the lock mechanism is detected, the lock is released in a state where the output of the internal combustion engine is reduced to reduce the hydraulic oil pressure. Therefore, the reverse torque due to the rotational inertia of the second rotating body is reduced, and the contact pressure generated by the lock hole and the lock pin can be reduced, so that the lock pin of the lock mechanism can be reliably released in any case. Can be performed.

1 is a schematic diagram showing an overall configuration of an internal combustion engine control system using an internal combustion engine valve timing control apparatus according to Embodiment 1 of the present invention; FIG. It is sectional drawing which shows the internal structure of the valve timing change mechanism in the valve timing control apparatus of an internal combustion engine. It is a sectional side view which shows the internal structure of the lock mechanism of the valve timing change mechanism in the valve timing control apparatus of an internal combustion engine. 1 is a configuration diagram of an electronic control device in a valve timing control device for an internal combustion engine according to Embodiment 1 of the present invention; FIG. 3 is a flowchart showing a control operation of an OCV drive determination means in the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention. 3 is a flowchart illustrating a control operation of a lock release failure determination unit in the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention. 4 is a flowchart showing a control operation of OCV drive control means in the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention. 5 is a flowchart showing a control operation of retry control in the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention. 3 is a timing chart showing an operation based on a control flow in the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention.

  Hereinafter, a valve timing control apparatus for an internal combustion engine according to Embodiment 1 of the present invention will be described in detail with reference to the drawings. 1 is a schematic diagram showing an overall configuration of a control system for an internal combustion engine using a valve timing control device for an internal combustion engine according to Embodiment 1 of the present invention. In FIG. 1, an intake shaft 131 and an exhaust side camshaft 121 for opening and closing an intake valve 131 and an exhaust valve 132 are connected to an output shaft 120 of the internal combustion engine 101 via a timing chain (not shown).

  A valve timing changing mechanism 110 is provided at the tip of each camshaft 121, 122, and the timing chain is wound around a sprocket 21 described later of the valve timing changing mechanism 110. Thus, when the output shaft 120 rotates with the operation of the internal combustion engine 101, the driving force is transmitted to the valve timing changing mechanism 110 via the timing chain, and the camshaft 121 rotates together with the valve timing changing mechanism 110. The configuration of the valve timing changing mechanism 110 will be described later.

  The fuel injection device 109 is provided in the intake passage of the internal combustion engine 101, and injects fuel into the intake passage at a predetermined timing. The fuel injected into the intake passage is mixed with air to become an air-fuel mixture, and is taken into the cylinder of the internal combustion engine 101 when the intake valve 131 is opened. The spark plug 108 fixed to the cylinder head of the internal combustion engine 101 generates a spark discharge at a predetermined timing by the ignition energy supplied from the ignition device 107 and ignites the air-fuel mixture in the cylinder. The exhaust gas of the air-fuel mixture ignited and combusted in the cylinder is discharged from the inside of the cylinder to the exhaust passage together with the opening of the exhaust valve 132.

  The hydraulic pressure supply source 114 includes an oil pan 115 that stores hydraulic oil and an oil pump 116. The oil pump 116 is driven and rotated by the output shaft 120 of the internal combustion engine 101, sucks the hydraulic oil stored in the oil pan 115, and discharges it as hydraulic oil having a predetermined hydraulic pressure.

  The OCV 111 is supplied with hydraulic oil having a predetermined hydraulic pressure discharged from the oil pump 116 via a supply oil passage 119, and supplies the supplied hydraulic oil via the advance oil passage 112 to the valve timing changing mechanism 122 described above. The supply of hydraulic oil to the valve timing changing mechanism is controlled so as to be supplied to the advance chamber or to the retard chamber via the retard oil passage 113. The OCV 111 controls the hydraulic oil in the advance chamber or retard chamber of the valve timing changing mechanism 122 to return to the oil pan 115 through the return oil passage 118. These operations will be further described later.

  The fuel injection device 109 injects fuel at a predetermined timing based on a control signal from the electronic control device 117. The ignition device 107 operates so as to generate an ignition spark from the spark plug 108 at a predetermined timing based on a control signal from the electronic control device 117. The OCV 111 controls a solenoid valve that constitutes the OCV 111 based on a control signal from the electronic control unit 117, and controls supply and discharge of hydraulic oil to the valve timing changing mechanism 110 as described later.

  Next, the configuration and operation of the valve timing changing mechanism 110 will be described in detail. FIG. 2 is a cross-sectional view showing the internal structure of a valve timing changing mechanism in a valve timing control device for an internal combustion engine, in which (a) shows a state in which the vane rotor can rotate (pin lock released state); b) shows the locked state (pin lock state) of the vane rotor. As shown in FIGS. 2A and 2B, a cam housing 202 as a first rotating body of the valve timing changing mechanism 110 formed integrally with the cam sprocket 201 is connected to the camshaft 121. The vane rotor 203 as the second rotating body is accommodated rotatably. The cam housing 202 and the vane rotor 203 are provided so as to be relatively rotatable on the same axis.

  The vane rotor 203 is provided with three vanes 204 protruding radially from the center thereof, and the cam housing 202 is provided with three accommodating chambers 205 for accommodating these vanes 204 respectively. Thus, in a state where the vane rotor 203 is accommodated in the cam housing 202, the accommodating chamber 205 is partitioned into an advance hydraulic chamber 206 and a retard hydraulic chamber 207 by the vane 204. By adjusting the hydraulic pressure in the advance hydraulic chamber 206 and the retard hydraulic chamber 207 arranged so as to sandwich the vane 204 in this way, the vane 204 moves in the storage chamber 205 and the vane rotor 203 is moved into the housing. It is comprised so that it may rotate within 202.

  The hydraulic oil is supplied to the advance hydraulic chamber 206 and the retard hydraulic chamber 207 via the OCV 111 by a mechanical oil pump 116 connected to the output shaft 120 of the internal combustion engine 101 as shown in FIG. Is called. As described above, the advance oil passage 112 is connected to the advance hydraulic chamber 206 of the valve timing changing mechanism 110, and the retard oil passage 113 is connected to the retard hydraulic chamber 27, respectively. The advance oil passage 112 and the retard oil passage 113 are connected to the oil pump 116 via the OCV 111.

  The hydraulic oil pumped up from the oil pan 115 by the oil pump 116 is selectively supplied to the hydraulic chambers 206 and 207 through the OCV 111. Further, the hydraulic oil discharged from the hydraulic chambers 206 and 207 with the rotation of the rotor 203 is returned to the oil pan 115. A part of the hydraulic oil discharged from the oil pump 116 is supplied as lubricating oil to each part of the internal combustion engine through a lubricating oil passage (not shown), and supplied to the lubricating part of each part of the internal combustion engine, and then to the oil pan 115. Returned.

  The OCV 111 includes a solenoid valve that is driven based on an electrical drive signal, and is provided separately for each valve timing changing mechanism 110 on the intake side and the exhaust side. The OCV 111 switches the connection mode of the respective oil passages 112 and 113 according to the duty of the drive signal. Specifically, the path to the advance oil path 113 and the retard oil path 112 is switched according to the duty of the drive signal, and the switching is performed at 50 [%] as a boundary.

  That is, when the duty of the drive signal is smaller than 50%, the hydraulic oil pumped up by the oil pump 116 is supplied to the advance hydraulic chamber 206 through the supply oil passage 119 and the advance oil passage 112. The hydraulic oil in the retarding hydraulic chamber 207 is returned to the oil pan 115 through the retarding oil passage 113 and the reflux oil passage 118. When the hydraulic pressure in the advance hydraulic chamber 206 is increased in this way, the rotor 203 rotates in the housing 202 clockwise in FIG. Along with this, the camshaft 121 rotates to the advance side, and the relative rotation phase of the camshaft 121 with respect to the output shaft 120 is displaced in a direction to advance the valve timing.

  On the other hand, when the duty of the drive signal is larger than 50%, the hydraulic oil pumped up by the oil pump 116 is supplied to the retarding hydraulic chamber 27 through the supply oil passage 119 and the retarding oil passage 113. The hydraulic oil in the advance hydraulic chamber 26 is returned to the oil pan 115 through the advance oil passage 112 and the reflux oil passage 118. When the hydraulic pressure in the retarding hydraulic chamber 207 increases in this way, the rotor 203 rotates counterclockwise in FIG. 2, that is, toward the retarded side indicated by the dashed arrow C in the housing 202. As a result, the camshaft 121 rotates to the retard side, and the relative rotation phase of the camshaft 121 with respect to the output shaft 120 is displaced in a direction that retards the valve timing.

  When the duty of the drive signal is set to 50 [%], the supply and discharge of the hydraulic oil in the hydraulic chambers 206 and 207 is stopped. The rotation of the rotor 203 is restricted, and the valve timing is maintained at that timing.

  The change of the valve timing by the valve timing changing mechanism 110 described above is performed by an electronic control unit 117 that controls the internal combustion engine 101 in an integrated manner. The electronic control unit 117 detects the rotation angle CA of the output shaft 120 of the internal combustion engine 101 and the crank angle sensor 102 that detects the rotation speed NE of the internal combustion engine, which is the rotation speed of the output shaft 120, and the rotation angle CAMA of the camshaft 121. Various sensors such as a cam position sensor 103 for detecting the internal combustion engine coolant temperature THW, an accelerator position sensor 106 for detecting an accelerator operation amount APS by the driver, and the like are connected. The electronic control device 117 captures signals output from these various sensors, executes various arithmetic processes, and based on the results, the ignition device 107, the fuel injection device 109, and other parts of the internal combustion engine provided in the internal combustion engine. Control.

  Specifically, the current relative rotational phase in the valve timing changing mechanism 110 is calculated based on the rotational angle CA of the output shaft 120 and the rotational angle CAMA of the camshaft 121. Then, the target phase is calculated based on the internal combustion engine speed NE so that the optimum valve timing is obtained, and the duty of the drive signal output to the OCV 111 is set so that the actual relative rotational phase matches this target phase. By controlling the OCV 111 by setting the duty in this way, the amount of hydraulic fluid supplied to the advance hydraulic chamber 206 and the retard hydraulic chamber 207 is adjusted, and the relative rotational phase of the output shaft 120 and the camshaft 121 is adjusted. By executing phase change control that changes the valve timing, the valve timing is changed to an appropriate timing according to the engine operating state.

  By the way, in the hydraulic drive type valve timing changing mechanism 110 as described above, the hydraulic pressure in each of the hydraulic chambers 206 and 207 is low when the hydraulic pressure supplied from the oil pump 116 to each of the hydraulic chambers 206 and 207 is small. Is insufficient, it is difficult to hold the rotor 203 in a predetermined phase, and the valve timing becomes unstable. Therefore, in the valve timing changing mechanism 110 according to the first embodiment, a lock mechanism 300 that holds the rotor 203 in a predetermined phase by mechanical engagement is provided, and each hydraulic chamber 206 is provided as when the internal combustion engine is started. , 207, the rotor 203 is held in a predetermined phase by the lock mechanism 300 when the hydraulic pressure is small. In the valve timing changing mechanism 110 according to the first embodiment, the lock mechanism 300 holds the rotor 203 at the most advanced angle phase at which the valve timing is most advanced.

  FIG. 3 is a side sectional view showing an internal structure of a lock mechanism of a valve timing changing mechanism in a valve timing control device for an internal combustion engine, where (a) is a pin lock state and (b) is a pin The unlocked state, (c) is the OCV drive duty 0 [%] (operating oil is supplied to the advance chamber) and [advance oil pressure> inverse inertia torque], and (d) is the OCV drive. In the state when duty is 0 [%] (operating oil is supplied to the advance chamber) and [advance hydraulic pressure <inertial reverse torque], (e), the OCV drive duty changes from 0 to 100 [%] (slow The state when the hydraulic oil is supplied to the corner chamber is shown.

  As shown in FIGS. 2 and 3, the lock mechanism 300 is provided in a lock hole 303 formed in one of the three storage chambers 205 and a reciprocating motion so as to protrude and retract from the vane 204. It includes a lock pin 301 that can be inserted into the lock hole 303.

  The lock pin 301 is always urged by the spring 302 in a direction protruding from the vane 24. An unlocking oil passage 304 is formed at the bottom of the lock hole 303 so as to communicate with the retarding hydraulic chamber 207 and to apply the hydraulic pressure of the hydraulic oil in the retarding hydraulic chamber 207 to the tip of the lock pin 301. . Accordingly, when the internal combustion engine is stopped when the oil pump 116 is not driven and the hydraulic pressure in the retarding hydraulic chamber 207 is lowered, the lock pin 301 protrudes from the vane 204 by the action of the urging force by the spring 302 and engages with the lock hole 303. Then, the movement of the rotor 203 is restricted ((a) of FIG. 3).

  On the other hand, when the operation of the internal combustion engine is started and the hydraulic pressure in the retarding hydraulic chamber 207 becomes a predetermined pressure or higher, the lock pin 31 is pushed back against the urging force of the spring 302 by the hydraulic pressure. The engagement between 301 and the lock hole 303 is released ((b) of FIG. 3).

  According to the valve timing changing mechanism 110 having the lock mechanism 300 configured as described above, the lock pin 301 can be used even when the hydraulic pressure in each of the hydraulic chambers 206 and 207 cannot be sufficiently ensured, such as when the internal combustion engine is started. Thus, the rotation of the rotor 203 can be restricted by the mechanical engagement, and the valve timing can be prevented from becoming unstable.

  By the way, when the valve timing changing mechanism 110 starts to operate, it is necessary to start the control after releasing the lock state. In order to release the locked state, as described above, the hydraulic pressure is supplied to the unlocking oil passage 304 and the lock pin 301 needs to be pushed back against the urging force of the spring 302.

  Here, if a force that moves the vane 204 to the retarded side acts before the lock is released due to some factor, the contact pressure at the engagement portion of the lock mechanism 300, that is, the contact portion between the lock pin 301 and the lock hole 303. As a result, the lock pin 301 is in a fixed state, and there is a possibility that the operation of accommodating the lock pin 301 in the vane 204 may be hindered.

  When the lock mechanism 300 is fixed in this manner and the unlocking operation of the locked state is hindered, the phase change control can be started immediately and the valve timing cannot be changed. In addition, if the phase change control is started in a state where the lock state by the lock mechanism 300 is not completely released and the hydraulic pressure in the retarding hydraulic chamber 207 is increased, the lock pin 301 is damaged or deformed. There is also a risk of

  Therefore, as in the conventional technique described in Patent Document 1 described above, the OCV drive duty is periodically changed with respect to the lock mechanism 300, thereby changing the relative positions of the lock hole 303 and the lock pin 301, As a result, the mechanism for releasing the lock in the expectation that the joined state is released, or the control start timing is adjusted as in the conventional technique described in Patent Document 2, and the lock hole 303 and the lock pin 301 are A technique has been proposed in which the OCV drive duty is controlled at a timing other than the joined state to start unlocking.

  However, in the case of the conventional valve timing control device for an internal combustion engine described in Patent Document 1, the reverse torque due to the rotation inertia generated with respect to the cam rotation direction is the same as the rotation direction corresponding to the retard side of the vane. Therefore, even if the drive duty of the OCV 111 is 0 [%], when the reverse torque due to the rotation inertia is small with respect to the advance oil pressure supplied to the advance hydraulic chamber, the lock pin 301 is in relation to the lock hole 303. Then, a state of causing contact on the retarded angle side occurs ((c) in FIG. 3). For this reason, when the vane operates on the retard side when the drive duty is 100 [%], contact with the retard hole on the retard side further increases, and the lock cannot be released. was there. Further, when the OCV 11 has a drive duty of 0 [%] and the reverse torque due to the rotational inertia is larger than the advance hydraulic pressure supplied to the advance hydraulic chamber, the lock pin 301 advances relative to the lock hole 303. A state of causing contact on the corner side occurs ((d) in FIG. 3).

  On the other hand, as described above, in the conventional valve timing control device for an internal combustion engine described in Patent Document 2, release of the lock pin is started when the crank angle is a predetermined angle. In adjusting to the angle, the fluctuation of the accuracy of the crank angle sensor, the fluctuation of the actuator from when the drive duty is applied to the OCV until the hydraulic pressure is supplied, and further the fluctuation of the flow resistance of the hydraulic oil passage itself are affected. There was a problem that it was difficult to adjust to a predetermined crank angle.

  The valve timing control apparatus for an internal combustion engine according to Embodiment 1 of the present invention has been made to solve the conventional problems as described above. Hereinafter, a valve timing control apparatus for an internal combustion engine according to Embodiment 1 of the present invention will be described in detail. In the valve timing control apparatus for an internal combustion engine according to the first embodiment, the internal combustion engine 101 is controlled before the hydraulic oil pressure is controlled in the rotational direction of the rotor 23 when the lock pin 301 is in the fixed state. By stopping the ignition device 107 and causing misfire, the output torque of the internal combustion engine 101 is temporarily reduced, so that the contact pressure between the lock pin 301 and the inner wall of the lock hole 303 is reduced, and the lock is released. It is.

FIG. 4 is a configuration diagram of an electronic control device in the valve timing control device for an internal combustion engine according to the first embodiment of the present invention. In FIG. 4, the electronic control unit 117 includes a rotational speed measuring unit 501, an actual advance amount measuring unit 502, an OCV drive determining unit 503, an unlocking failure determining unit 504 as an unlocking determining unit, and an OCV. Drive control means 505 and ignition control means 506 are provided. As described above, the electronic control unit 117 includes the crank angle sensor 102 that detects the rotation angle CA of the output shaft 120 of the internal combustion engine 101, the cam position sensor 103 that detects the cam position, the water temperature sensor 104, and the accelerator position sensor. Various sensors such as 106 are connected, signals output from these various sensors are captured, various arithmetic processes are executed, and based on the results, an ignition device 107, an OCV 111, a fuel injection device 109 provided in the internal combustion engine 101, In addition, each part of the internal combustion engine is controlled.

  The rotation number counting means 501 detects the reference crank angle based on the output signal from the crank angle sensor 102, measures the interval (cycle) of the output signal of the crank angle sensor, and calculates the interval of the internal combustion engine 101 from the reciprocal of the cycle. Count the number of revolutions. The actual advance amount measuring means 502 measures the current actual phase angle from the input timing of the output of the cam angle sensor 103 on the basis of the input timing of the output signal of the crank angle sensor 102, and sets a preset valve timing changing mechanism. The current actual advance angle amount is calculated from the deviation between the phase angle 110 during non-operation and the actual phase angle.

  The OCV drive determining unit 503 determines whether or not the valve timing control is in a state for executing. FIG. 5 is a flowchart showing the control operation of the OCV drive determination means in the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention. In FIG. 5, in step S 501, the engine rotational speed from the rotational speed measuring means 501, the water temperature from the water temperature sensor 104, and the accelerator position from the accelerator position sensor 106 are read. In step S502, it is determined whether the driving condition of the OCV 111 is satisfied.

The driving condition of the OCV 111 is to satisfy all of the following.
-Number of revolutions of internal combustion engine 101> predetermined number of revolutions ThNE
・ Water temperature of the internal combustion engine> predetermined water temperature ThTHW
Accelerator opening> Predetermined accelerator opening ThAPS
It is.

  As a result of the determination in step S502, if it is determined that the driving condition for the OCV 111 is satisfied (Y), it is determined that a sufficient environment for driving the OCV 111 is prepared, and an OCV driving determination flag is set in step S503. Set and finish the process. Note that the above-described determination values for the driving conditions of the OCV 111 are values set in advance for operating the valve timing mechanism and are experimentally adapted, but from the warm-up state of the internal combustion engine 101, Usually, conditions assuming traveling are set. For example, a predetermined rotation speed ThNE = 1000 [rpm], a predetermined water temperature ThTHW = 40 [deg. CA], a predetermined accelerator opening ThAPS = 0 [%].

  On the other hand, if the result of determination in step S502 is that the drive condition of the OCV 111 is not satisfied (N), the OCV drive determination flag is reset in step S504.

  Next, the unlocking failure determination unit 504 performs the unlocking failure determination. FIG. 6 is a flowchart showing the control operation of the unlocking failure determination means in the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention. In FIG. 6, in step S601, the actual advance amount is read from the actual advance amount measuring means 502. Next, the process proceeds to step S602, and it is identified whether or not the unlocking in the valve timing changing mechanism 110 is not performed. That is, it is determined whether the OCV drive determination flag is set and the unlocking failure condition is satisfied.

The unlocking failure conditions are as follows.
・ | Target advance amount−Actual advance amount |> α and Target advance amount> β
In this case, specifically, α = 5 [deg. CA], β = 10 [deg. CA].
The target advance amount is a value set in advance and is defined as a rotation speed table.

  As a result of the determination in step S602, if it is determined that the OCV drive determination flag is set and the unlocking failure condition is satisfied (Y), the process proceeds to step S603, where the release failure flag is set, and the process is performed. finish. On the other hand, if the result of determination in step S602 is negative (N), the release failure flag is reset in step S604, and the process ends.

  Next, the OCV drive control unit 505 changes the driving method of the OCV 111 according to the above-described unlocking state determined by the unlocking failure determination unit 504. FIG. 7 is a flowchart showing the control operation of the OCV drive control means in the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention. In FIG. 7, in step S701, it is determined whether or not the OCV drive determination flag is set. If it is set (Y), the process proceeds to step S702, and whether or not the release failure flag is set. Determine. As a result of the determination, if the release failure flag is set (Y), retry control is performed in step S70S. Details of the retry control in step S703 will be described later.

  As a result of the determination in step S701, if the OCV drive determination flag is not set (N), the process proceeds to step S704, where the OCV drive duty is set to 0 [%], and the process proceeds to step S705, where the drive duty is 0 [ %] OCV drive signal is output to the OCV 111, and the process is terminated.

  On the other hand, if the release failure flag is not set as a result of the determination in step S702 (N), that is, if the OCV drive determination flag is established and the lock state is not established, the routine proceeds to step S706 as a normal control and is retried. The middle flag is reset, and then the misfire instruction flag is reset in step S707. The misfire instruction flag will be described later. Next, proceeding to step S708, the OCV drive duty is calculated using PID control using the deviation between the target advance angle amount and the actual advance angle amount so as to follow the actual advance angle to the target advance angle, and step S705. Then, the OCV drive signal having the calculated drive duty is output to the OCV 111, and the process is terminated.

  Next, as a result of the determination in step S702, it is determined that the release failure flag is set (Y), that is, it is determined that the lock state is set, and the process proceeds to step S703 to shift to the execution of retry control. explain. FIG. 8 is a flowchart showing the control operation of the retry control in the valve timing control apparatus for the internal combustion engine according to the first embodiment of the present invention.

  In FIG. 8, in step S801, it is determined whether or not the retry flag is reset. If the retry flag is reset, the retry control condition is satisfied (Y), and the process proceeds to step S802. The drive duty is once set to 0 [%]. Next, in step S803, a misfire instruction flag is set in order to reduce the torque of the internal combustion engine 101, and an ignition cut is performed. In step S804, a retry flag is set, and the process ends.

  On the other hand, if the retry flag is not reset as a result of the determination in step S801 (N), the process proceeds to step S805 to determine whether the OCV drive duty 0 [%] in the retry control is continued. That is, in step S805, it is determined whether or not the state where the OCV drive duty is 0 [%] continues for a predetermined time or more. If it continues (Y), the process proceeds to step S806, where the OCV drive duty is normally controlled. Is set to 100%, and the misfire state is canceled and the process is terminated.

  Here, the predetermined time used for the determination in step S805 is such that the OCV drive duty 0 [%] state continues and the hydraulic oil pressure is sufficiently reduced, and the actuator is caused by torque reduction due to misfire of the internal combustion engine 101. This is a time corresponding to a state where the torque is reduced, and is a preset value.

  The execution time of the retry control shown in FIG. 8 is defined as the time for which the torque reduction due to misfire of the internal combustion engine 101 is reflected, for example, two revolutions of the internal combustion engine 101.

  The series of processes related to the retry control for unlocking the valve timing changing mechanism 110 described above is repeatedly executed by the electronic control unit 117 during the operation of the internal combustion engine 101.

  Next, the operation of the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention will be described with reference to a timing chart. FIG. 9 is a timing chart showing the operation based on the control flow in the valve timing control apparatus for an internal combustion engine according to the first embodiment of the present invention, where (a) is a release failure flag and (b) is being retried. (C) is a misfire instruction flag, (d) is a cam torque, (e) is an OCV drive duty, (f) is a retarded hydraulic pressure, (g) is a lock pin locked state, and (h) is an actual advance amount. , Respectively.

  In FIG. 9, the release failure flag of (a) is a variable in the electronic control unit 117 calculated by the lock release failure determination means 504, and indicates that the lock release failure is determined in the set state. The retry flag in (b) is a variable in the electronic control unit 117 calculated by the OCV drive control means 503, and indicates that retry control is being performed in the set state. The misfire instruction flag in (c) is a variable in the electronic control unit 117 calculated by the OCV drive control means 505, and indicates that the misfire is instructed to the ignition control means 506 in the set state, thereby causing a misfire. The cam torque in (d) indicates the force actually acting on the vane rotor 203. The OCV drive DUTY of (e) is calculated by the OCV drive control means 505, and indicates the DUTY value of the PWM signal output from the electronic control unit 117 to the OCV 111. The retarded hydraulic pressure (f) indicates a pressure generated by supplying oil from the OCV 111 to the retarded oil chamber. The lock state (g) indicates the state of the lock mechanism in the valve timing changing mechanism 110. The actual advance amount (h) is a variable in the electronic control unit 117 calculated by the actual advance amount measuring means 502.

  In FIG. 9, first, at the timing of time t1, the lock release failure determination means 504 determines that the release failure is based on the deviation between the actual advance amount and the target advance amount, and the release failure flag is set. Set (1). Along with this, the retry flag is set in the OCV drive control means 503 (2). At the same time, with the setting of the retry flag (2), a misfire instruction flag is set (3) to instruct a misfire. Then, the OCV drive duty is set to 0 [%] (4).

  Thereafter, after a time that is set in advance by the OCV drive control means 505 assuming that the advance hydraulic pressure becomes zero at the timing of time t2 (time from time t1 to time t2), the OCV drive duty is increased. Is set to 100 [%]. After that, when the locked state is released along with the increase of the retarded hydraulic pressure at the timing of time t3 (6), the actual advance angle amount is increased, and the unlocking failure determination means 504 makes the release failure at the timing of time t4. The flag is reset (7). At the same time, the retry flag is reset by the OCV drive control means 505 (8), the misfire instruction flag is reset (9), and ignition is started. Also, the normal control of the OCV drive duty is restored (10).

  As described above, driving in a state where the lock pin 301 is joined to the lock hole 303 is avoided, so that it is possible to avoid a state in which the lock pin 301 is poorly released.

  The means for reducing the torque of the internal combustion engine 101 may be performed by fuel cut in addition to the above-described ignition cut. Further, intermittent cutting of the cylinder may be used as means for reducing the output torque of the internal combustion engine 101.

  In the present invention, the embodiments can be appropriately modified or omitted within the scope of the invention.

101 internal combustion engine, 102 crank angle sensor, 103 cam angle sensor,
104 water temperature sensor, 105 accelerator pedal, 106 accelerator position sensor,
107 ignition device, 108 spark plug, 109 fuel injection device,
110 valve timing changing mechanism, 111 oil control valve, 112 advance oil passage, 113 retard oil passage, 114 oil pressure reduction, 115 oil pan,
116 oil pump, 117 electronic control unit, 118 reflux oil passage,
119 supply oil passage, 120 output shaft, 121 camshaft,
201 cam sprocket, 202 cam housing, 203 vane rotor, 205 storage chamber, 206 advance hydraulic chamber, 207 retard oil passage, 300 lock mechanism,
301 lock pin, 302 spring, 303 lock hole,
304 oil passage for unlocking, 501 rotation speed measuring device, 502 actual advance angle measuring device,
503 OCV drive determination means, 504 unlock release failure determination means, 505 OCV drive control means, 506 ignition control means

Claims (3)

A first rotating body connected to the output shaft of the internal combustion engine;
Connected to a camshaft that opens and closes an intake valve or an exhaust valve of the internal combustion engine, shares an axis with the first rotating body and is housed in the first rotating body, and is attached to the first rotating body. A second rotating body configured to be relatively rotatable around the axis,
A lock hole formed in one of the first rotating body and the second rotating body, and the other of the first rotating body and the second rotating body provided on the other of the axial center. A lock pin formed so as to be movable in the same direction as the extending direction, and the lock pin moves to the lock hole side and engages with the lock hole, whereby the second rotating member with respect to the first rotating body is engaged. and a lock mechanism capable of locking the rotation of the rotating body,
While releasing the lock by the lock mechanism, while applying a biasing force to rotate the second rotating body relative to the second rotating body by hydraulic oil supplied from an oil control valve based on rotation of the output shaft of the internal combustion engine, Applying a biasing force by the hydraulic oil to the lock pin engaged with the lock hole so as to release the engagement between the lock pin and the lock hole, to release the lock, and to A valve timing control device for an internal combustion engine configured to control valve timing for opening and closing the intake valve or the exhaust valve by rotating relative to a first rotating body ;
Oil control valve drive determining means for determining whether or not the operating state of the internal combustion engine is in a state of controlling the oil control valve to control the valve timing;
A lock release determination means for determining whether or not the lock is released based on an actual advance angle amount and a target advance angle amount of the intake valve or the exhaust valve;
With
When the oil control valve drive determining means determines that the valve timing is being controlled and the unlock determination means determines that the lock has not been released , the output of the internal combustion engine is reduced. In the state where the hydraulic pressure of the hydraulic oil is reduced, the lock is released.
A valve timing control device for an internal combustion engine characterized by the above. The reduction of the output of the internal combustion engine is performed by setting the internal combustion engine to a misfire state.
The valve timing control apparatus for an internal combustion engine according to claim 1, wherein The reduction in the output of the internal combustion engine is performed by stopping the supply of fuel to the internal combustion engine.
The valve timing control apparatus for an internal combustion engine according to claim 1, wherein

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