JP4536342B2 - Control device for internal combustion engine with variable compression ratio mechanism - Google Patents

Description

  The present invention relates to a technique for controlling engine torque in relation to a compression ratio in an internal combustion engine having a variable compression ratio mechanism with a variable compression ratio.

In an internal combustion engine, the higher the compression ratio, the better the fuel consumption rate, but knocking tends to occur during high-load operation. Therefore, in an engine with a variable compression ratio, there is a technique for improving the fuel consumption rate without causing knocking by setting a high compression ratio during low load operation and a low compression ratio during high load operation. This is shown as a basic method (see Patent Document 1).
Japanese Patent Application No. 2002-140874

In addition, if the compression ratio is lowered, the exhaust temperature increases as the exhaust heat increases due to a decrease in thermal efficiency, so when trying to increase the catalyst temperature for catalyst activation, the compression ratio is lowered and the time until activation is reduced. There has also been proposed a technique for controlling the compression ratio so as to be different from the basic technique depending on the situation, such as shortening.
However, if the load is low and the compression ratio is increased when the catalyst activation is promoted in order to improve the fuel consumption rate, the engine torque is reduced accordingly, so for the driver, The torque generated with respect to the accelerator opening will be reduced, and the user will feel uncomfortable. Further, for example, when accelerating from a constant vehicle speed, when the compression ratio is lowered as described above, it is assumed that the accelerator is depressed more than usual in order to compensate for the small generated torque. In this case, there is a possibility that a shift shock due to a downshift that does not normally occur may occur. Thus, in the situation where the driver needs to have a low compression ratio in an unexpected state, there is a problem that the drivability deteriorates.

  The present invention has been made paying attention to such a conventional problem, and provides a control device for an internal combustion engine with a variable compression ratio mechanism that can ensure good operability while controlling the compression ratio according to demand. The purpose is to provide.

For this reason, the present invention
Control of the internal combustion engine that controls the engine torque by operating the torque operating means based on the target operation amount, and variably controls the compression ratio by driving the variable compression ratio mechanism that makes the compression ratio variable based on the target compression ratio A first target compression ratio based on a basic engine operating state including an accelerator opening, and a second target based on conditions other than the basic engine operating state with respect to the variable compression ratio mechanism. From the compression ratio , while setting the final target compression ratio based on conditions other than the basic engine operating state ,
And the engine torque in the first target engine load and the first target compression ratio that is set based on the basic engine operating conditions including the accelerator opening, calculated by correcting the first target engine load The second target engine load is calculated so that the second target engine load and the engine torque at the second target compression ratio are the same, and the engine torque in the same basic engine operating state is The final target operation amount of the torque operating means is set based on the second target engine load so as to be constant regardless of the final target compression ratio .

In this way, if the target compression ratio changes or is corrected according to a specific engine operating state such as a change in basic engine operating state (rotation speed, load) or catalyst inactivity, the compression ratio will change. The engine torque changes accordingly, but the target operating amount of the torque operating means is set based on the engine operating state and the final target compression ratio of the variable compression ratio mechanism, so that this compression ratio change can be reduced. The target operation amount can be set so as to eliminate the corresponding torque change. As a result, the relationship between the amount of operation by the driver (accelerator opening) and the engine torque can be maintained in a desired relationship regardless of the change in the compression ratio, so that a good operation can be performed while controlling the compression ratio according to the demand. Sex can be secured.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is an overall view of an engine (internal combustion engine) including a multi-link type piston-crank mechanism that also serves as a variable compression ratio mechanism.
The crankshaft 31 includes a plurality of journal portions 32, a crankpin portion 33, and a counterweight portion 31a. The journal portion 32 is rotatably supported by a main bearing of a cylinder block (not shown) serving as an engine body. . The crankpin portion 33 is eccentric from the journal portion 32 by a predetermined amount, and a lower link 34 serving as a second link is rotatably connected thereto.

The lower link 34 has a substantially T-shape, and the crank pin portion 33 is fitted in a substantially central connecting hole that can be divided from a main body 34a and a cap 34b.
The upper link 35 serving as the first link has a lower end side rotatably connected to one end of the lower link 34 by a connecting pin 36, and an upper end side rotatably connected to a piston 38 by a piston pin 37. The piston 38 receives combustion pressure and reciprocates in the cylinder 39 of the cylinder block.

Above the cylinder 39, there are an intake valve 43 that opens and closes the intake port 44 in synchronization with the rotation of the crankshaft 31, and an exhaust valve 45 that opens and closes the exhaust port 46 in synchronization with the rotation of the crankshaft 31. Has been placed.
The control link 40 serving as the third link is pivotally connected at its upper end side to the other end of the lower link 34 by a connecting pin 41, and its lower end side can be pivoted to an appropriate position of the engine body, for example, a cylinder block via the control shaft 42. It is connected to. Specifically, the control shaft 42 is supported by the engine body so as to rotate about the small diameter portion 42b, and the lower end portion of the control link 40 is rotatable on the large diameter portion 42a that is eccentric to the small diameter portion 42b. Is fitted.

  The rotation position of the small diameter portion 42 b is controlled by a compression ratio control actuator 43. When the small-diameter portion 42b rotates, the axial center position of the large-diameter portion 42a that is eccentric with respect to the small-diameter portion 42b, in particular, the relative position with respect to the engine body changes. Thereby, the rocking | fluctuation support position of the lower end of the control link 40 changes. When the swing support position of the control link 40 changes, the stroke of the piston 38 changes, and the position of the piston 38 at the piston top dead center (TDC) moves up and down (that is, the y coordinate in FIG. 1 increases). Thereby, the engine compression ratio can be changed. The compression ratio control actuator 43 can hold the small-diameter portion 42b at an arbitrary rotation position against a reaction force applied from the control link 40. As the compression ratio control actuator 43, a hydraulic vane actuator is used.

  2 to 4 show a hydraulic system for controlling the compression ratio control actuator 43. In the figure, a compression ratio control actuator 43 includes a drive shaft 43b connected to the small-diameter portion 42b in a housing 43a and a vane that is fixed to the drive shaft 43b and divides the inside of the housing 43a into an A chamber and a B chamber whose volume is variable. 43c is stored in a freely rotating manner. On the other hand, the discharge port of the oil pump 102 driven by the electric motor 101 is connected to the check valve 103, the on-off valve 104, and the port c of the direction switching valve 105, and the port d of the direction switching valve 105 is connected to the low-pressure side oil. Connected to pan 106. The ports e and f of the direction switching valve 105 are connected to the ports a and b of the compression ratio control actuator 43, respectively. An accumulator 107 is connected to an oil passage that branches from between the check valve 103 and the on-off valve 104, and an oil passage that branches from between the on-off valve 104 and the direction switching valve 105 is connected to the engine oil gallery. .

  In the state shown in FIG. 2, the on-off valve 104 is opened and the direction switching valve 105 is controlled to the left end in the figure, and the high-pressure oil discharged from the oil pump 102 is connected to the ports c and e of the on-off valve 104 and the direction switching valve 105. The oil is supplied from the port a of the compression ratio control actuator 43 to the A chamber, and the oil in the B chamber is returned from the port b to the oil pan 106 through the ports f and d of the direction switching valve 105. As a result, the volume of the chamber A increases, and the small diameter portion 42b rotates clockwise in the drawing together with the vane 43c, and the swing support position of the control link 40 is changed to be controlled to a low compression ratio.

  On the other hand, when the direction switching valve 105 is controlled to be switched to the right end in the figure as shown in FIG. 3 from the above state, the high-pressure oil is transferred from the port b to the compression ratio control actuator 43 via the ports c and f of the on-off valve 104. The oil in the chamber A is returned to the oil pan 106 from the port a through the ports e and d of the direction switching valve 105. As a result, the volume of the B chamber increases, and the small diameter portion 42b rotates counterclockwise in the drawing together with the vane 43c, and the swing support position of the control link 40 changes to be controlled to a high compression ratio. In the case of holding on the high compression ratio side, as shown in FIG. 4, the direction switching valve 105 is moved to the center of the figure and the on-off valve 104 is closed.

  Returning to FIG. 1, this engine includes a turbocharger 51 as a supercharger. The turbocharger 51 has a configuration in which a turbine 52 located in an exhaust passage 54 and a compressor 53 located in an intake passage 55 are coaxially arranged. In order to control the supercharging pressure in accordance with operating conditions, An exhaust bypass valve 56 for bypassing a part of the exhaust from the upstream side of the turbine 52 is provided. An exhaust purification catalyst 50 such as a three-way catalyst is interposed in the exhaust passage 54 downstream of the turbine 52.

The intake passage 55 downstream of the compressor 53 is provided with a throttle valve 57 as torque operating means for variably controlling the intake fresh air amount, and the throttle valve 57 is driven by a throttle actuator 58 such as a step motor.
Further, an EGR passage 59 branched from the engine main body of the exhaust passage 54 and the turbine 52 and connected to the intake passage 55 downstream of the throttle valve 57, and an EGR valve 60 interposed in the EGR passage 59 are provided. It has been.

The EGR valve 60 is, for example, an electronically controlled type using a step motor, and controls the amount of exhaust gas recirculated to the intake side according to the opening, that is, the EGR amount sucked into the engine body.
As sensors for detecting the engine operating state, an accelerator opening sensor 61 that detects an accelerator opening operated by a driver, a rotation speed sensor 62 that detects an engine rotation speed, and an overpressure that detects a boost pressure upstream of the throttle valve 57. A supply pressure sensor 63, a compression ratio sensor 64 for detecting the actual compression ratio, a water temperature sensor 65 for detecting the engine coolant temperature, and a knocking sensor 66 for detecting knocking are provided. The detection signals from these sensors are the engine control unit. (ECU) 67.

In the engine having such a configuration, the ECU 67 controls the compression ratio by the variable compression ratio mechanism and the throttle valve 57 according to the actual compression ratio controlled by the variable compression ratio mechanism, together with various engine controls (fuel injection control, ignition control, etc.). The opening degree control is executed as follows.
The whole throttle valve control in the first embodiment will be described according to the flowchart of FIG. 8 with reference to the block diagram of FIG.

In step 1, the target compression ratio of the variable compression ratio mechanism is set.
In step 2, the variable compression ratio mechanism is driven so as to achieve the set target compression ratio.
In step 3, the target throttle opening is set based on the engine operating state (accelerator opening and engine speed) and the target compression ratio.
In step 4, the throttle valve 57, which is torque operating means, is operated according to the target throttle opening.

Next, details of setting the target compression ratio in step 2 will be described according to the flowchart of FIG. 9 with reference to the block diagram of FIG.
In step 11, a target compression ratio A for activating the exhaust purification catalyst 50 is set. The target compression ratio A may be simply set to the minimum compression ratio, but may be set to a smaller value as the catalyst temperature detected by the temperature sensor or estimated from the water temperature or the like is lower.

In step 12, the minimum compression ratio is set as the target compression ratio B corresponding to the time when the driving force of the variable compression ratio mechanism is insufficient. As the compression ratio increases, the reaction force to the variable compression ratio mechanism increases and the required driving force increases, so that when the driving force is insufficient, the minimum compression ratio is stabilized.
In step 13, the basic value of the target compression ratio C according to the normal operation state is set with reference to the map shown in FIG. 11 based on the accelerator opening and the engine speed as the engine operation state. Specifically, as the required engine load corresponding to the accelerator opening increases, the tendency of knocking to increase increases, so the compression ratio is reduced to suppress knocking. Set to.

In step 14, the combustion chamber wall temperature is detected. This can be detected with high accuracy if a wall temperature sensor is provided in the vicinity of the combustion chamber, but may be simply estimated based on the engine water temperature detected by the water temperature sensor 65.
In step 15, a wall temperature correction coefficient for correcting the target compression ratio C is set based on the combustion chamber temperature with reference to the map shown in FIG. Specifically, since the tendency of knocking increases as the combustion chamber temperature increases, the wall temperature correction coefficient is set to a small value so as to reduce the compression ratio in order to suppress knocking.

Instead of correcting with the wall temperature of the combustion chamber, a configuration in which the intake air temperature is detected and an intake air temperature correction coefficient is set may be corrected. Also in this case, as the intake air temperature becomes higher, the tendency of knocking to increase increases. Therefore, the intake air temperature correction coefficient is set to a small value so as to reduce the compression ratio in order to suppress knocking.
In step 16, the steady reached intake air amount is calculated with reference to the map shown in FIG. 13 based on the accelerator opening and the engine speed. Here, the steady reached intake air amount is an intake air amount sucked into the cylinder in a steady state determined by the current operation state (accelerator opening degree and engine speed).

In step 17, the intake air amount correction coefficient is set by dividing the calculated steady intake air amount by the actual intake air amount detected by the air flow meter 2. That is, since the delay of the actual intake air amount is large with respect to the change in the supercharging pressure by the turbocharger 51, the basic value of the target compression ratio C set corresponding to the steady state is corrected according to the delay of the actual intake air amount. Therefore, the intake air amount correction coefficient is set.
In step 18, the target compression ratio C is calculated by multiplying the basic value of the target compression ratio C by the wall temperature correction coefficient and the intake air amount correction coefficient.

In step 19, the target compression ratio selected from the target compression ratios A, B, and C set as described above according to the following conditions (see FIG. 14) is set as the final target compression ratio. That is,
When the catalyst temperature is lower than the catalyst activation temperature and the drive hydraulic pressure of the variable compression ratio mechanism is equal to or higher than a predetermined hydraulic pressure (condition 1), the target compression ratio A is selected.

When the compression ratio drive oil pressure is less than the predetermined oil pressure (condition 2), the target compression ratio B is selected.
When both conditions 1 and 2 are not satisfied (condition 3), that is, when the drive hydraulic pressure of the variable compression ratio mechanism is equal to or higher than a predetermined hydraulic pressure and the catalyst temperature is equal to or higher than the catalyst activation temperature, the target compression ratio C is selected.
Next, details of the target throttle opening setting in step 3 of FIG. 8 will be described according to the flowchart of FIG. 10 with reference to the block diagram of FIG.

In step 21, the first target intake air amount ratio is set with reference to the map shown in FIG. 15 based on the engine speed and the accelerator opening. Here, the intake air amount ratio is a ratio of the actual intake air amount to the intake air amount (standard state) with the throttle fully opened as a parameter of the intake air amount. The first target intake air amount ratio is a value calculated using the compression ratio as a predetermined constant.
In step 22, based on the target compression ratio set as described above, an intake air amount correction value is calculated with reference to the map shown in FIG. This intake air ratio correction value is obtained by changing the intake air ratio to the engine torque that changes depending on the difference between the target compression ratio and the predetermined constant in the first target intake air ratio calculated with the compression ratio as a predetermined constant as described above. It is a value set to maintain the same value by correcting.

In step 23, the intake air ratio correction value is added to the first target intake air ratio to obtain a second target intake air ratio.
In step 24, based on the second target intake air amount ratio, a target throttle opening is set with reference to the map of FIG.
As described above, in this embodiment, the basic value of the target operation amount corresponding to the engine operating state (accelerator opening degree and engine speed) is set in accordance with the target compression ratio of the variable compression ratio mechanism with respect to the throttle valve that is the torque operation means. Therefore, even if the compression ratio changes, the torque can be kept constant, and good driving performance can be achieved while controlling the compression ratio as required. Can be secured.

In the present embodiment, the first target intake air ratio is set as the first target engine load based on the engine operating state, and the first intake air ratio is set according to the target compression ratio of the variable compression ratio mechanism. The second target intake air amount ratio is corrected and the second target intake air amount ratio is calculated, and the final target operation amount of the torque operating means is set based on the second target intake air amount ratio.
That is, it is possible to directly correct the throttle opening to correct the throttle opening (target operation amount) with respect to the target compression ratio, but the opening to be corrected also varies depending on the state of the differential pressure across the throttle. This complicates the computation. On the other hand, if the throttle opening is corrected through correction of the intake air amount ratio, which is the engine load, as in the present embodiment, correction according to demand can be performed with high accuracy and simple calculation.

Next, a second embodiment will be described. First, the whole aspect of the throttle valve control in the second embodiment will be described according to the flowchart of FIG. 21 with reference to the block diagram of FIG.
In step 51, the first target compression ratio of the variable compression ratio mechanism is set with reference to the map of FIG. 11 based on the accelerator opening and the engine speed. This first target compression ratio is the same as the basic value of the target compression ratio C set in step 21 of the first embodiment.

In step 52, the first target compression ratio is corrected to set a second target compression ratio.
In step 53, the variable compression ratio mechanism is driven so as to achieve the second target compression ratio.
In step 54, a second target compression ratio is subtracted from the first target compression ratio to calculate a target compression ratio difference value.

In step 55, a target throttle opening is set based on the engine operating state (accelerator opening and engine speed) and the target compression ratio difference value.
In step 56, the throttle valve 57, which is torque operating means, is operated according to the target throttle opening.
Next, details of the second target compression ratio setting in step 52 will be described according to the flowchart of FIG. 22 with reference to the block diagram of FIG.

In steps 61 and 62, the target compression ratio A for catalyst activation and the target compression ratio B for reducing the driving force of the variable compression ratio mechanism are set as in steps 11 and 12 of FIG. 9 of the first embodiment.
Steps 63 to 67 are similar to steps 14 to 18 in FIG. 9. Combustion chamber wall temperature detection, wall temperature correction coefficient setting, intake air amount detection, steady reached intake air amount calculation, intake air amount ratio correction coefficient Set up.

In step 68, the target compression ratio C is calculated by multiplying the first target compression ratio by the wall temperature correction coefficient. In step 69, the target compression ratios A, B, and C are selected in the same manner as in step 20 of FIG. Then, the final target compression ratio is set.
Next, details of the target throttle opening setting in step 55 of FIG. 21 will be described according to the flowchart of FIG. 23 with reference to the block diagram of FIG.

In step 71, the first target intake air ratio is set with reference to the map shown in FIG. 24 based on the engine speed and the accelerator opening. Here, in FIG. 15 in the first embodiment, the compression ratio is set as a predetermined constant, that is, the first target intake air amount ratio is set without considering the change in the compression ratio, but in FIG. 24, the engine speed and the accelerator opening are set. The first target intake air amount ratio is set in consideration of the first target compression ratio (= the basic value of the target compression ratio C in the first embodiment) set accordingly. That is, as shown in FIG. 11, when the accelerator opening is small and the engine speed is high, the first target compression ratio is set to a large value, so that the engine torque generated for the same intake amount ratio Becomes larger. Therefore, in contrast to FIG. 15, in FIG. 24, when the accelerator opening is small and when the engine speed is high, the intake amount ratio is corrected and set to be small so that the same torque can be obtained.

  In step 72, based on the target compression ratio difference value calculated by subtracting the second target compression ratio from the first target compression ratio, the target intake air amount ratio correction value is referred to with reference to the map shown in FIG. Is calculated. Specifically, the compression ratio decreases as the second target compression ratio set as the final target compression ratio is smaller than the first target compression ratio, that is, as the target compression ratio difference value increases with a positive value. In order to compensate for the torque drop associated with this, the intake air amount correction amount is set to be increased by a positive value.

In step 73, the intake air ratio correction value is added to the first target intake air ratio to obtain a second target intake air ratio.
In step 74, the target throttle opening is set with reference to the map of FIG. 17 based on the second target intake air ratio.
As described above, in the present embodiment, the first target compression ratio set based on the basic engine operation state (accelerator opening degree, engine speed) is set as the catalyst active state, the drive torque of the variable compression ratio mechanism, the combustion wall. While performing the compression ratio control with the second target compression ratio corrected and set in accordance with conditions other than the basic engine operating state such as the temperature and intake air temperature as the final target compression ratio, the torque operating means For a certain throttle valve, the basic value of the target manipulated variable according to the basic engine operating state and the corresponding first target compression ratio is set to the difference between the first target compression ratio and the second target compression ratio. Accordingly, correction is performed, and a final target operation amount is set and operated.

Thereby, the target operation amount is corrected according to the correction of the target compression ratio, the engine torque can be maintained constant, and good drivability can be ensured while controlling to the compression ratio according to the request. .
Further, a first intake air amount ratio is set as a first target engine load based on the engine operating state, and according to a difference between the first target compression ratio and the second target compression ratio of the variable compression ratio mechanism. The first intake amount ratio is corrected to set the second intake amount ratio, and the final target operation amount of the throttle valve is set based on the second intake amount ratio. As in the first embodiment, the throttle opening is corrected through correction of the intake air amount ratio, which is the engine load, based on the target compression ratio difference value. Therefore, the calculation is simple and can be performed with high accuracy as required.

In the above embodiments, the hydraulic compression type mechanism is shown as the variable compression ratio mechanism. However, the variable compression ratio mechanism can be applied to an electric type. Of course, when the driving force is reduced, the power is reduced (when the battery voltage is reduced). The target compression ratio B may be set.
In the above embodiment, the intake air amount ratio is set as the engine load set as the first and second target engine loads. However, in addition to this, the engine torque, the intake air amount, the fuel injection amount, and the like may be set.

  In addition to the throttle valve, the torque operation means may be a means for operating the fuel injection amount.

The system block diagram of the engine provided with the control apparatus which concerns on this invention. The figure which shows operation | movement when operating to a low compression ratio by the variable compression ratio mechanism of an apparatus same as the above. The figure which similarly shows the operation | movement when operating to a high compression ratio. The figure which similarly shows operation | movement when maintaining a high compression ratio. The control block diagram of 1st Embodiment. The block diagram of target compression ratio setting similarly. The block diagram of target throttle opening similarly. The flowchart of the main routine of control similarly. The flowchart of a target compression ratio setting similarly. The flowchart of target throttle opening setting similarly. Similarly, a characteristic map for obtaining the target compression ratio from the accelerator opening and the engine speed. Similarly, a characteristic map for finding the wall temperature correction coefficient from the combustion chamber wall temperature. Similarly, a characteristic map for obtaining the steady-state intake air amount from the accelerator opening and the engine speed. Similarly, a characteristic map for selecting a target compression ratio from the driving force of the variable compression ratio mechanism and the catalyst temperature. Similarly, a characteristic map for setting the first target intake air amount ratio from the accelerator opening and the engine speed. Similarly, a characteristic map for setting the target intake air amount ratio correction amount from the target compression ratio. Similarly, a characteristic map for setting the second target intake air amount ratio from the accelerator opening and the engine speed. The control block diagram of 2nd Embodiment. The block diagram of target compression ratio setting similarly. The block diagram of target throttle opening similarly. The flowchart of the main routine of control similarly. The flowchart of a target compression ratio setting similarly. The flowchart of target throttle opening setting similarly. Similarly, a characteristic map for obtaining the target compression ratio from the accelerator opening and the engine speed. Similarly, a characteristic map for calculating a target intake air ratio correction amount from a target compression ratio difference value.

Explanation of symbols

31 crankshaft 34 lower link 35 upper link 38 piston 40 control link 42 control shaft 43 compression ratio control actuator 57 throttle valve 58 throttle actuator 61 accelerator opening sensor 62 rotation speed sensor 64 compression ratio sensor 65 water temperature sensor 66 knocking sensor 67 ECU

Claims (10)

Control of the internal combustion engine that controls the engine torque by operating the torque operating means based on the target operation amount, and variably controls the compression ratio by driving the variable compression ratio mechanism that makes the compression ratio variable based on the target compression ratio A first target compression ratio based on a basic engine operating state including an accelerator opening, and a second target based on conditions other than the basic engine operating state with respect to the variable compression ratio mechanism. From the compression ratio , while setting the final target compression ratio based on conditions other than the basic engine operating state ,
And the engine torque in the first target engine load and the first target compression ratio that is set based on the basic engine operating conditions including the accelerator opening, calculated by correcting the first target engine load The second target engine load is calculated so that the second target engine load and the engine torque at the second target compression ratio are the same, and the engine torque in the same basic engine operating state is An internal combustion engine with a variable compression ratio mechanism, wherein a final target operation amount of the torque operating means is set based on the second target engine load so as to be constant regardless of a final target compression ratio Control device.   The first target engine load is set correspondingly when the basic engine operating state and the compression ratio of the variable compression ratio mechanism are predetermined constants, and the second target engine load is the final target engine load. 2. The control apparatus for an internal combustion engine according to claim 1, wherein the second target engine load is calculated by correcting the first target engine load in accordance with a difference between a target compression ratio and the predetermined constant.   The first target engine load is set based on the basic engine operating state and a first target compression ratio of the variable compression ratio mechanism, and the second target engine load is a first target compression ratio. 2. The control apparatus for an internal combustion engine with a variable compression ratio mechanism according to claim 1, wherein the first target engine load is corrected and calculated according to a difference between the first target engine compression ratio and the final target compression ratio.   The final target compression ratio of the variable compression ratio mechanism is set including a correction according to the temperature of the exhaust purification catalyst interposed in the engine exhaust system. The control device for an internal combustion engine with a variable compression ratio mechanism according to any one of the above.   5. The final target compression ratio of the variable compression ratio mechanism is set to include correction according to at least one of the intake air temperature and the combustion chamber wall temperature. 6. A control device for an internal combustion engine with a variable compression ratio mechanism according to claim 1.   The final target compression ratio of the variable compression ratio mechanism is set including correction according to a decrease in driving force of the variable compression ratio mechanism. The control apparatus of the internal combustion engine with a variable compression ratio mechanism described in 1.   The drive force reduction of the variable compression ratio mechanism is a decrease in the hydraulic pressure when the drive source is a hydraulic pressure, and a decrease in the power when the drive source is an electric power. Control device for internal combustion engine with variable compression ratio mechanism.   When the driving force of the variable compression ratio mechanism is reduced, the target compression ratio corrected according to the reduction of the driving force is set as the final target compression ratio, and when the driving force is satisfied, the engine exhaust When the temperature of the exhaust purification catalyst interposed in the system is lower than the activation temperature, the target compression ratio corrected to promote the activation of the catalyst is set as the final target compression ratio, and the catalyst temperature is activated. The target compression ratio corrected according to at least one of the intake air temperature and the combustion chamber wall temperature when the temperature is equal to or higher than the control temperature is set as a final target compression ratio. A control device for an internal combustion engine with a variable compression ratio mechanism according to claim 1.   The engine load set by the first target engine load and the second target engine load is the engine torque, the intake air amount, the ratio of the intake air amount when the throttle valve provided in the intake system is fully opened to the intake air amount, fuel injection The control device for an internal combustion engine with a variable compression ratio mechanism according to any one of claims 1 to 8, wherein the control device is an amount.   The control of an internal combustion engine with a variable compression ratio mechanism according to any one of claims 1 to 9, wherein the torque operating means is means for operating either an intake air amount or a fuel injection amount. apparatus.

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