JP5708200B2 - Control device for variable valve mechanism - Google Patents

Description

  The present invention relates to a control device for a variable valve mechanism.

  2. Description of the Related Art A variable valve mechanism that makes variable valve characteristic values of engine valves such as intake valves and exhaust valves is known. Such a variable valve mechanism is driven by a control shaft, and the valve characteristic is appropriately changed by controlling the position of the control shaft so that the detection position of the control shaft matches the target position.

  Here, for example, if a temporary stop of energization occurs, such as a momentary interruption of energization to the control device, it becomes difficult to accurately detect the operation position of the control axis, and the detected position of the control axis and the actual position (actual And the valve characteristics cannot be changed appropriately.

  In view of this, the apparatus described in Patent Document 1 is provided with a control shaft whose movable limit position is set by a regulating member such as a stopper. Then, the control shaft is moved until it hits the regulating member, and the deviation between the detected position of the control shaft and the actual position is corrected using the detected position of the control shaft detected at that time.

  Further, in the apparatus described in the document 1, when the control shaft is moved until it hits the restricting member, the operation speed of the control shaft is decelerated so as to be equal to or lower than a predetermined value, and thereby the control shaft hits the restricting member. I try to reduce the impact.

JP 2008-215247 A

  In the conventional apparatus described above, the deviation between the detected position of the control shaft and the actual position cannot be corrected until the control shaft hits the restricting member. Therefore, when the actual position is shifted to the movable limit position side with respect to the detection position, the control shaft hits the restricting member before starting the deceleration of the operation speed as described above, and the control shaft hits the restricting member. There is a possibility that the impact of the can not be mitigated.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a control device for a variable valve mechanism that can more suitably suppress an impact when a control shaft hits a regulating member.

In the following, means for achieving the above object and its effects are described.
A control apparatus for a variable valve mechanism for solving the above problems includes a variable valve mechanism that varies a valve characteristic of an engine valve, a variable valve mechanism that drives the variable valve mechanism, and a movable limit position is set by a regulating member. A control shaft, a detecting means for detecting the operation position of the control shaft, and a deceleration that decelerates the operation speed so that the operation speed of the control shaft becomes a predetermined value or less when the control shaft is moved until it hits the restricting member Means for controlling the drive of the control shaft so that the detection position of the control shaft detected by the detection means coincides with the target position of the control shaft. when deenergization to the control device of the variable valve mechanism prior to moving the control shaft until it hits the member has occurred, moves the control shaft until it hits the regulating member Saishi and, as its gist in that it comprises a timing changing means for quickly than when the deceleration start timing of the operating speed by the speed reduction means the energization-stopping does not occur.

According to this configuration, when the control shaft is moved until it hits the restricting member, when the energization stop has occurred for the control device of the variable valve mechanism before the start of the movement, that is, the detection position and the actual position of the control shaft When there is a difference between the two, the start timing for decelerating the operation speed of the control axis is advanced. Therefore, it is possible to slow down the operation speed of the control shaft before it hits the restricting member, and it is possible to more suitably suppress the impact when the control shaft hits the restricting member.

In an example of the control device for the variable valve mechanism, the target position is set so as to be continuously displaced until the control shaft reaches the movable limit position, and the operation speed is reduced by the target position is intended to be started after reaching a predetermined deceleration start position, the timing changing means, correct the deceleration start position in a direction away from the movable limit position.

Further, in one example of a control device of the variable valve mechanism, the deceleration of the operating speed, the detection position is intended to be started after reaching a predetermined deceleration start position, the timing changing means starts the deceleration correct position in a direction away from the movable limit position.

According to these above-described configuration, when moving the control shaft until it hits the regulating member, when the energization stop has occurred with respect to its drive before detection means, than when the energization stop has not occurred, the The deceleration start position is corrected in a direction away from the movable limit position. Therefore, when the energization stop occurs, the operation speed deceleration start timing can be made earlier than when the energization stop does not occur.

Furthermore, in the example of the control device for the variable valve mechanism, the control unit includes an estimation unit that estimates a deviation amount between the actual position of the control shaft and the detection position that is generated while the energization is stopped. to set the shift amount as a correction value of the deceleration start position.

According to this configuration, an appropriate correction value can be set according to the amount of deviation between the actual position of the control axis and the detected position.
In an example of the control device for the variable valve mechanism, the estimating means calculates a deviation amount in unit time immediately after the energization stop based on the operation speed immediately before the occurrence of the energization stop, and the deviation amount in the unit time. And calculating the amount of deviation per unit time that decreases with the passage of time during the energization stop, and integrating the amount of deviation per unit time during the energization stop so that the control during the energization stop period is performed. It calculates the deviation between the detected position and the actual position of the axis.

  The operation position of the control shaft while power is stopped is displaced by the inertia of the operation so far. The magnitude of the inertia acting on the control shaft during the energization stop can be grasped from the operation speed of the control shaft immediately before the energization stop occurs. In view of this, in this configuration, the amount of deviation generated during the energization stop is estimated from the operation speed of the control shaft immediately before the energization stop occurs. Therefore, according to the above configuration, it is possible to more accurately estimate the deviation amount during the energization stop in consideration of inertia.

The schematic diagram which shows the whole structure about one Embodiment of the control apparatus of the variable valve mechanism of this invention. The schematic diagram which shows the whole structure of the valve operating system of the internal combustion engine to which the embodiment is applied. The perspective sectional view of the variable valve mechanism provided in the internal combustion engine to which the embodiment is applied. The timing chart which shows the position change of a control axis when an energization stop occurs. 6 is a flowchart showing a procedure of a shift amount calculation process in the embodiment. The flowchart which shows the procedure of the speed limit process in the embodiment. The timing chart which shows the effect | action of the speed limiting process in the embodiment.

Hereinafter, an embodiment in which a control device for a variable valve mechanism according to the present invention is embodied will be described with reference to FIGS.
As shown in FIG. 1, the control device in the present embodiment drives a variable valve mechanism 1 that varies the maximum lift amount and the valve opening period, which are valve characteristics of the intake valve, and the variable valve mechanism 1. And an engine control unit 4 as a command unit that controls the entire engine including the variable valve mechanism 1.

  The drive mechanism 2 includes an electric motor 200 as a power source, a control shaft 3 that operates the variable valve mechanism 1, and a conversion mechanism 201 that converts the rotational motion of the motor 200 into linear motion of the control shaft 3. Yes. The drive mechanism 2 also includes a drive control unit (hereinafter sometimes referred to as “EDU”) 203 for performing drive control of the motor 200. The EDU 203 includes a rotation amount sensor 202 that detects the rotation amount of the motor 200, and the operation position (detection position S) in the axial direction of the control shaft 3 is based on the rotation amount detected by the rotation amount sensor 202. Calculated. The rotation amount sensor 202 and the EDU 203 that calculates the detection position S based on the rotation amount detected by the rotation amount sensor 202 constitute the detection means.

  Further, the EDU 203 includes a CPU 203a that performs each arithmetic processing related to the control of the drive mechanism 2, a ROM 203b that stores a control program and initial position data, and a RAM 203c that stores a detection result of the rotation amount sensor 202 and the like. Yes. The EDU 203 is powered by a vehicle battery (not shown). The operating position of the control shaft 3 is controlled by the EDU 203 so that the detection position S of the control shaft 3 and the target position P coincide with each other.

  Further, the operating position of the control shaft 3 is changed within a preset range, and the movable limit position is defined by a stopper as a restricting member that restricts the movement of the control shaft 3.

  On the other hand, the engine control unit (hereinafter may be referred to as “ECU”) 4 includes a CPU 4a that performs each arithmetic processing related to the control of the internal combustion engine, and a ROM 4b that stores a control program and data. . The ECU 4 also includes a RAM 4c that temporarily stores and holds the results calculated by the CPU 4a, reading values of each sensor, and values received from the EDU 203, and a timer 4d that indicates the startup time of the ECU 4. Various sensors (not shown) are connected to the ECU 4, and the control shaft 3 for obtaining the target value of the valve characteristic of the intake valve 10 and the target value of the valve characteristic in accordance with the operating state and the driver's command. A target value (target position P) of the operating position is calculated. In the present embodiment, the ECU 4 is configured to serve as the estimation means.

  The ECU 4 and the EDU 203 are electrically connected by a bus type communication network (hereinafter also referred to as “CAN”) 13 as a communication line. The CAN 13 transmits / receives a target position P, a detection position S, an estimated value (shift amount Z) of an operation position at the time of return of energization stop, which will be described later, and the like between the ECU 4 and the EDU 203.

Next, the configuration of the variable valve mechanism controlled by the control device will be described with reference to FIGS.
As shown in FIG. 2, the variable valve mechanism 1 is arranged between a cam 6 provided on the camshaft 5 and an intake valve 10. The variable valve mechanism 1 is swingably installed on a rocker shaft 7 disposed parallel to the camshaft 5 and includes an input arm 100 and an output arm 101.

  The input arm 100 includes a roller 102 that contacts the cam 6 and a protrusion 103. A spring 104 is in contact with the protrusion 103, and the roller 102 is urged against the cam 6 by the restoring force of the spring 104.

  When the cam 6 pushes down the input arm 100 through the roller 102 due to the rotation of the camshaft 5, the variable valve mechanism 1 swings and the output arm 101 pushes down the roller rocker arm 9. The roller rocker arm 9 is installed so as to be swingable by the roller 11, and the roller rocker arm 9 pushes down the intake valve 10 against the valve spring 12 by swinging of the roller rocker arm.

  The internal structure of the variable valve mechanism 1 is shown in FIG. As shown in FIG. 3, an internal gear is provided inside the input arm 100 and the output arm 101, and a substantially cylindrical slider gear 106 is disposed so as to mesh with the internal gear. The slider gear 106 is movable integrally with the control shaft 3 in the axial direction. An input gear 107 having a helical spline at the center in the longitudinal direction is formed on the outer periphery of the slider gear 106, and an output gear 108 having a helical spline is formed on both sides in the longitudinal direction. In the helical splines of the input gear 107 and the output gear 108, the inclination directions of the tooth traces are reversed.

  In such a variable valve mechanism 1, when the control shaft 3 moves in the axial direction, the input arm 100 and the output arm 101 rotate in the reverse direction in accordance with the helical spline teeth. Therefore, the relative position of the input arm 100 and the output arm 101 changes. Specifically, when the control shaft 3 is moved in the H direction of the arrow shown in FIG. 3, the relative positions change so as to be separated from each other, and the maximum lift amount and the valve opening period of the intake valve 10 are increased. Note that the movement of the control shaft 3 in the direction of the arrow H can be moved to the movable limit position defined by the stopper provided in the direction of the arrow H, and the movement in the direction in which the maximum lift amount and the valve opening period are increased. The limit position is hereinafter referred to as Hi end.

  When the control shaft 3 is moved in the L direction indicated by the arrow, the relative positions change so as to approach each other, and the maximum lift amount and the valve opening period of the intake valve 10 are reduced. The movement of the control shaft 3 in the direction of the arrow L can be moved to a movable limit position defined by a stopper provided in the direction of the arrow L, and the movement in the direction in which the maximum lift amount and the valve opening period are reduced. The limit position is hereinafter referred to as Lo end.

Incidentally, in the present embodiment, as the control shaft 3 moves in the direction in which the maximum lift amount and the valve opening period of the intake valve 10 increase, the value of the detection position S changes to a larger value.
In this way, the variable valve mechanism 1 makes the maximum lift amount and the valve opening period of the intake valve 10 variable by changing the relative positions of the input arm 100 and the output arm 101. Since the output arm 101 is biased upward in FIG. 2 by the valve spring 12, the control shaft 3 is biased in the L direction of the arrow. As a result, the maximum lift amount and the valve opening period are not inadvertently increased.

  For such a variable valve mechanism 1, the ECU 4 calculates the target value so as to obtain an optimum valve characteristic in response to the driving state of the vehicle and the command from the driver, and the EDU 203 that receives this calculates the target value. By issuing an operation command to the mechanism 2, its valve characteristics are changed.

  By the way, if a temporary stop of energization such as a momentary interruption of energization occurs in the EDU 203 of the drive mechanism 2, it becomes difficult to accurately detect the operation position of the control shaft 3, and the detection position S of the control shaft 3 is detected. And the actual position R (actual operating position) is displaced, and the valve characteristics cannot be changed appropriately. That is, when the energization is stopped, the operation position of the control shaft 3 cannot be detected, but the control shaft 3 moves to some extent due to inertia even during the energization stop. Therefore, even if the detection position immediately before the energization stop is used as the detection position at the time of energization return at the time of the energization return, the change in position of the control shaft 3 moved by inertia during the energization stop is not taken into account. There is a deviation from the position R (actual operating position).

  Therefore, in the drive mechanism 2, the control shaft 3 is moved until it hits the stopper, that is, the control shaft 3 is moved to the movable limit position. The deviation between the detected position S and the actual position R is corrected using the detected position S of the control shaft 3 detected when the movable limit position is reached. Such deviation correction is performed by moving the control shaft 3 to the Hi end or to the Lo end.

  Further, when the drive mechanism 2 moves the control shaft 3 to the movable limit position, when the control shaft 3 reaches the deceleration start position G set before the movable limit position, the operation speed ( = Operation speed of the motor 200) is decelerated so as to be equal to or less than a predetermined value, thereby reducing the impact when the control shaft 3 hits the stopper.

  Here, as described above, the deviation between the detected position S and the actual position R of the control shaft 3 cannot be corrected until the control shaft 3 hits the stopper. Therefore, as shown in FIG. 4, when the actual position R is shifted to the movable limit position side by the shift amount Z with respect to the detection position S, the timing at which the operation speed starts to be reduced (time t2). Since the control shaft 3 hits the stopper before (time t1), there is a possibility that the impact when the control shaft 3 hits the stopper cannot be sufficiently mitigated.

Therefore, in the present embodiment, the deviation amount Z during energization stop is estimated through the following processing, and the deceleration start position G is corrected using the estimated deviation amount Z.
First, the calculation process of the deviation amount Z will be described with reference to FIG. This process is repeatedly executed by the ECU 4 at predetermined intervals. This calculation process constitutes the estimation means.

  When this process is started, it is first determined whether or not an energization stop has occurred (S100). Here, when mutual communication between the ECU 4 and the EDU 203 via the CAN is interrupted, it is determined that the energization stop has occurred (S100: YES), and the operation speed V of the control shaft 3 immediately before the occurrence of the energization stop is determined. Based on this, the shift amount Z is calculated (S110).

  In step S110, the displacement amount Z is calculated as follows. The magnitude of the shift amount Z during the energization stop is affected by the magnitude of inertia acting on the control shaft 3 during the energization stop, the energization stop time, and the like.

  The magnitude of the inertia acting on the control shaft 3 while the energization is stopped can be estimated from the operating speed V of the control shaft 3 immediately before the energization is stopped. Therefore, the estimated value of the inertia is obtained so that the magnitude of the inertia acting on the control shaft 3 immediately after the energization stops increases as the operation speed V of the control shaft 3 immediately before the energization stops increases. Then, from this estimated value of inertia, the shift amount of the operation position in the unit time immediately after the energization is stopped is calculated as an initial value D.

  Further, the amount of deviation per unit time due to inertia decreases with the passage of time due to deceleration due to friction or the like. Therefore, by multiplying the initial value D by a coefficient that gradually decreases from the value “1” toward the time “0” as time elapses, the amount of deviation per unit time at a predetermined time during energization stop is calculated. Then, by integrating the deviation amount per unit time during the energization stop, an estimated value of the deviation amount Z in the entire energization stop period is calculated.

When the calculation of the deviation amount Z is completed in this way, the present process is temporarily terminated. The calculated deviation amount Z is stored and held in the RAM 4c.
Next, with reference to FIG. 6, a speed limiting process for reducing the operating speed of the control shaft 3 when the control shaft 3 is moved to the Hi end will be described. This process is executed by the EDU 203 when the control shaft 3 is moved to the Hi end.

  When this process is started, first, the deceleration start position G is corrected (S200). Here, the deceleration start position G is corrected from the initial value by subtracting the correction value A from the preset initial setting value GS of the deceleration start position. Further, the deviation amount Z stored and held in the RAM 4c is set as the correction value A. Accordingly, when there is no deviation amount Z between the detection position S and the actual position R of the control shaft 3, the initial set value GS is set as the deceleration start position G, and in this case, the deceleration start position is substantially set. Is not corrected. On the other hand, when the deviation amount Z occurs, the deceleration start position G is corrected in a direction away from the movable movement limit position (that is, the Hi end) by the deviation amount Z with respect to the initial set value GS.

  Next, it is determined whether or not the target position P of the control shaft 3 has exceeded the deceleration start position G calculated in step S200 (S210). When the target position P has not reached the deceleration start position G (S210), the present process is temporarily terminated without changing the changing speed of the target position P.

  On the other hand, when the target position P exceeds the deceleration start position G (S210: YES), the speed limit is started to limit the operation speed of the control shaft 3 (S220), and this process is temporarily ended. Is done. In step S <b> 220, the change speed of the target position P after the target position P reaches the deceleration start position G is lower than the change speed before the target position P reaches the deceleration start position G. As a result, after the target position P reaches the deceleration start position G, the operating speed of the control shaft 3 is decelerated as compared to before reaching the deceleration start position G, and this causes an impact when the control shaft 3 hits the stopper. Alleviated. The process of step S200 constitutes the timing changing means, and the process of step S220 constitutes the deceleration means.

  FIG. 7 shows the action obtained by executing the speed limiting process when the control shaft 3 is moved to the movable limit position on the Hi end side. Incidentally, as shown in FIG. 7, even when the actual position R of the control shaft 3 and the detection position S are deviated, the operation position of the control shaft 3 is controlled so that the detection position S and the target position P coincide with each other. Therefore, even when the shift amount Z is generated, the detection position S and the target position P substantially coincide with each other.

  As shown in FIG. 7, when the shift amount Z is generated, the deceleration start position G is corrected by the shift amount Z in the direction away from the movable limit position. Therefore, when the control shaft 3 is moved until it hits the stopper, the EDU 203 is deenergized before the movement starts, and a deviation occurs between the detection position S and the actual position R of the control shaft 3. Sometimes the following effects are obtained. That is, the start timing for decelerating the operation speed of the control shaft 3 is earlier than when the deceleration start position G is not corrected (time t1). Therefore, even when the actual position R and the detection position S of the control shaft 3 are shifted, the operation speed of the control shaft 3 can be reduced before the control shaft 3 hits the stopper. Therefore, the impact when the control shaft 3 hits the stopper can be suppressed more appropriately.

As described above, according to the present embodiment, the following effects can be obtained.
(1) When energization stop has occurred to the EDU 203 before moving the control shaft 3 until it hits the stopper, when the control shaft 3 is moved until it hits the stopper, the deceleration start timing of the operation speed of the control shaft 3 is It is set to be faster than when no energization is stopped. Therefore, it is possible to slow down the operating speed of the control shaft 3 before the control shaft 3 hits the stopper, and it is possible to more suitably suppress the impact when the control shaft 3 hits the stopper.
(2) When energization is stopped for the EDU 203, the deceleration start position G is corrected in a direction away from the movable limit position. Accordingly, when the energization stop has occurred, the deceleration start timing of the operation speed of the control shaft 3 can be made earlier than when the energization stop has not occurred.
(3) Since the deviation amount Z between the actual position R of the control shaft 3 and the detection position S generated during the energization stop is estimated, this deviation amount Z is set as the correction value A for the deceleration start position G. Thus, an appropriate correction value A can be set in accordance with the amount of deviation Z between the actual position R and the detection position S of the control shaft 3.
(4) The deviation amount Z is calculated based on the operating speed V of the control shaft 3 immediately before the energization stop occurs. Accordingly, it is possible to more accurately estimate the deviation amount Z during the energization stop in consideration of the inertia applied to the control shaft 3 during the energization stop.

In addition, the said embodiment can also be changed and implemented as follows.
As described above, even when the actual position R and the detection position S of the control shaft 3 are deviated, the detection position S and the target position P substantially coincide with each other. Accordingly, in step S210 shown in FIG. 6, it is determined whether or not the target position P exceeds the deceleration start position G, but it is determined whether or not the detection position S exceeds the deceleration start position G. You may do it. That is, the deceleration of the operating speed of the control shaft 3 may be started after the detection position S reaches the deceleration start position G. Even in this case, if the deceleration start position G is corrected in a direction away from the movable limit position, the timing at which the detection position S reaches the deceleration start position G is advanced. Therefore, when the energization stop occurs, the energization stop occurs. It is possible to make the operation speed deceleration start timing earlier than when the operation is not performed.

  Although the deviation amount Z is set as it is as the correction value A of the deceleration start position G, a value obtained by multiplying the deviation amount Z by a correction coefficient may be set as the correction value A. Further, a value other than the deviation amount Z, for example, a fixed value set appropriately may be set as the correction value A. That is, the correction value A may be a value that corrects the deceleration start position in a direction away from the movable limit position so that the deceleration start timing of the operation speed of the control shaft 3 is advanced.

  In FIG. 7, the case where the control shaft 3 is moved to the Hi end is illustrated. In addition, the speed limiting process may be performed when the control shaft 3 is moved to the Lo end. In this case, the initial setting value of the deceleration start position as described above is also provided in the vicinity of the Lo end, and in step S200, the correction value A is set in a direction in which the initial setting value set in the vicinity of Lo is away from the Lo end. Make corrections by minutes.

  The variable valve mechanism 1 is a mechanism that changes the maximum lift amount VL and the valve opening period of the intake valve 10 by driving the control shaft 3 in the axial direction. However, the valve characteristic is changed in another manner. It may be a mechanism. For example, a mechanism that changes the valve characteristic of the intake valve 10 by rotating the control shaft may be used.

  In the above embodiment, the variable valve mechanism 1 is provided for the intake valve 10. In addition, even when the variable valve mechanism 1 is provided for the exhaust valve, the present invention can be similarly applied.

  The variable valve mechanism 1 in the above embodiment is a mechanism that makes both the maximum lift amount and the valve opening period of the engine valve variable. However, the present invention can change only the maximum lift amount or only the valve opening period. The same can be applied to the variable valve mechanism.

  DESCRIPTION OF SYMBOLS 1 ... Variable valve mechanism, 2 ... Drive mechanism, 3 ... Control shaft, 4 ... Engine control unit (ECU), 4a ... ECU CPU, 4b ... ECU ROM, 4c ... ECU RAM, 4d ... Timer, 5 ... Camshaft, 6 ... Cam, 7 ... Rocker shaft, 8 ..., 9 ... Roller rocker arm, 10 ... Intake valve, 11 ... Roller of roller rocker arm, 12 ... Valve spring, 13 ... CAN, 100 ... Input arm, 101 ... Output arm, 102 ... Input arm roller, 103 ... Protrusion, 104 ... Spring, 106 ... Slider gear, 107 ... Input gear, 108 ... Output gear, 200 ... Motor, 201 ... Conversion mechanism, 203 ... Drive control unit (EDU) , 203a ... CPU of EDU, 203b ... ROM of EDU, 203c ... RAM of EDU, 202 ... Rotation amount sensor

Claims (2)

A variable valve mechanism that varies a valve characteristic of the engine valve, a control shaft that drives the variable valve mechanism and has a movable limit position set by a restricting member, and a detection unit that detects an operation position of the control shaft; And a decelerating means for decelerating the operation speed of the control shaft so that the operation speed of the control shaft is less than or equal to a predetermined value when the control shaft is moved until it hits the restricting member, and the control shaft detected by the detection means In the control device for the variable valve mechanism that controls the drive of the control shaft so that the detection position matches the target position of the control shaft,
When energization is stopped for the control device of the variable valve mechanism before moving the control shaft until it hits the restricting member, when the control shaft is moved until it hits the restricting member, Timing change means for making the operation speed deceleration start timing faster than when the energization stop has not occurred ,
An estimation means for estimating an amount of deviation between the actual position of the control axis and the detection position generated during the energization stop;
The estimation means calculates a deviation amount in unit time immediately after the energization stop based on the operation speed immediately before the occurrence of the energization stop, and with the passage of time during the energization stop based on the deviation amount in the unit time. The amount of deviation between the actual position of the control shaft and the detected position during the energization stop period is calculated by calculating the amount of deviation per unit time that decreases and integrating the amount of deviation per unit time during the energization stop. To calculate
The target position is set so as to be continuously displaced until the control shaft reaches the movable limit position, and the deceleration of the operation speed starts after the target position reaches a predetermined deceleration start position. Is,
The timing changing means sets the deviation amount as a correction value of the deceleration start position, and corrects the deceleration start position in a direction away from the movable limit position based on the correction value. Control device for the mechanism. A variable valve mechanism that varies a valve characteristic of the engine valve, a control shaft that drives the variable valve mechanism and has a movable limit position set by a restricting member, and a detection unit that detects an operation position of the control shaft; And a decelerating means for decelerating the operation speed of the control shaft so that the operation speed of the control shaft is less than or equal to a predetermined value when the control shaft is moved until it hits the restricting member, and the control shaft detected by the detection means In the control device for the variable valve mechanism that controls the drive of the control shaft so that the detection position matches the target position of the control shaft,
When energization is stopped for the control device of the variable valve mechanism before moving the control shaft until it hits the restricting member, when the control shaft is moved until it hits the restricting member, Timing change means for making the operation speed deceleration start timing faster than when the energization stop has not occurred ,
An estimation means for estimating an amount of deviation between the actual position of the control axis and the detection position generated during the energization stop;
The estimation means calculates a deviation amount in unit time immediately after the energization stop based on the operation speed immediately before the occurrence of the energization stop, and with the passage of time during the energization stop based on the deviation amount in the unit time. The amount of deviation between the actual position of the control shaft and the detected position during the energization stop period is calculated by calculating the amount of deviation per unit time that decreases and integrating the amount of deviation per unit time during the energization stop. To calculate
The deceleration of the operation speed is started after the detection position reaches a predetermined deceleration start position,
The timing changing means sets the deviation amount as a correction value of the deceleration start position, and corrects the deceleration start position in a direction away from the movable limit position based on the correction value. Control device for the mechanism.

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