JP4345307B2 - Control device for internal combustion engine with variable compression ratio mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for an internal combustion engine in an internal combustion engine including a variable compression ratio mechanism that can change a compression ratio and a variable valve mechanism that can change the valve opening / closing timing of an intake valve.
[0002]
[Prior art]
A variable compression ratio mechanism that changes the compression ratio of an internal combustion engine in accordance with the operating state of the internal combustion engine has been proposed. In addition, a variable valve mechanism that mainly changes the opening / closing timing of the intake valve in accordance with the operating state of the internal combustion engine has been put into practical use. Furthermore, a supercharging mechanism for supplying compressed intake air into a cylinder of an internal combustion engine has been put into practical use.
[0003]
Also, in order to obtain high efficiency, low fuel consumption, and high output, the operating state of the internal combustion engine is divided into three regions, a low load region, a medium load region, and a high load region. A technique for controlling the operation of the variable valve mechanism and the supercharging mechanism has been proposed (for example, Patent Document 1). In addition to this, a technique for controlling the variable compression ratio mechanism and the supercharging mechanism according to the load of the internal combustion engine in order to suppress knocking exclusively has been proposed (for example, Patent Document 2).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 63-120820 [Patent Document 2]
Japanese Utility Model Publication No. 63-150048 gazette
[Problems to be solved by the invention]
However, depending on the above prior arts, there has been a problem that the fuel consumption rate is not sufficiently improved, and in particular, the fuel consumption rate in the middle load region is not sufficiently improved. In addition, there is a problem that the output torque reaches a peak in a high load region.
[0006]
The present invention has been made to solve the above-described problems, and an object of the present invention is to improve fuel efficiency in a medium load region in an internal combustion engine including a variable compression ratio mechanism, a variable valve mechanism, and a supercharging mechanism. . Another object of the present invention is to increase output torque in a high load region in an internal combustion engine including a variable compression ratio mechanism, a variable valve mechanism, and a supercharging mechanism.
[0007]
[Means for solving the problems and actions / effects]
In order to solve the above-described problems, a first aspect of the present invention provides a control device for an internal combustion engine having an intake valve that communicates or blocks the inside of the cylinder of the internal combustion engine and the atmosphere. A control apparatus for an internal combustion engine according to a first aspect of the present invention includes: a variable valve mechanism that changes a closing timing of the intake valve; a variable compression ratio mechanism that changes a mechanical compression ratio of the internal combustion engine; A supercharging mechanism for supplying compressed intake air into the cylinders of the internal combustion engine; required torque detection means for detecting a required torque for the internal combustion engine; and when the detected required torque is in a medium load region The closing timing of the intake valve is delayed by the variable valve mechanism, the mechanical compression ratio of the internal combustion engine is increased by the variable compression ratio mechanism, and the supercharging mechanism is operated to compress the cylinder into the cylinder of the internal combustion engine. And an operation control means for supplying the supplied intake air.
[0008]
According to the control apparatus for an internal combustion engine according to the first aspect of the present invention, when the required torque is in the middle load region, the valve closing timing of the intake valve is delayed by the variable valve mechanism, and the internal combustion engine by the variable compression ratio mechanism. In an internal combustion engine having a variable compression ratio mechanism, a variable valve mechanism, and a supercharging mechanism, since the mechanical compression ratio of the engine is increased and the supercharging mechanism is operated to supply the compressed intake air into the cylinder of the internal combustion engine. In addition, the fuel efficiency in the middle load region can be improved.
[0009]
The control apparatus for an internal combustion engine according to the first aspect of the present invention may further include a cooler for reducing the temperature of the compressed intake air introduced into the cylinder of the internal combustion engine from the supercharging mechanism. In such a case, since the temperature of the intake air can be kept low even after being compressed in the cylinder, it is possible to further prevent the occurrence of knocking when the supercharger is operated.
[0010]
In the control device for an internal combustion engine according to the first aspect of the present invention, in the intermediate load region, a torque that is approximately ½ of the maximum torque that is output from the internal combustion engine when the supercharging mechanism is operated is required as the required torque. It may be a load area.
[0011]
In the control apparatus for an internal combustion engine according to the first aspect of the present invention, the operation control means may be configured such that when the detected required torque is in a high load region where the load is larger than the medium load region, the variable operation is performed. The intake air compressed by the valve mechanism advances the closing timing of the intake valve, lowers the mechanical compression ratio of the internal combustion engine by the variable compression ratio mechanism, operates the supercharging mechanism, and is compressed into the cylinder of the internal combustion engine May be supplied.
[0012]
According to the control apparatus for an internal combustion engine according to the first aspect of the present invention, when the required torque is in the high load region where the load is larger than the medium load region, the valve closing timing of the intake valve is set by the variable valve mechanism. Since the mechanical compression ratio of the internal combustion engine is lowered by the variable compression ratio mechanism and the supercharging mechanism is operated to supply the compressed intake air into the cylinder of the internal combustion engine, the variable compression ratio mechanism, the variable valve mechanism and In an internal combustion engine having a supercharging mechanism, output torque can be increased in a high load region.
[0013]
A second aspect of the present invention provides a control device for an internal combustion engine. The control apparatus for an internal combustion engine according to the second aspect of the present invention includes a supercharging mechanism, a variable valve mechanism that changes at least the closing timing of the intake valve, and a variable that changes the mechanical compression ratio of the internal combustion engine. A compression ratio mechanism; requested torque detecting means for detecting a requested torque for the internal combustion engine; and when the detected requested torque is in a first load region, the variable valve mechanism closes the intake valve. The timing is retarded, the mechanical compression ratio of the internal combustion engine is increased by the variable compression ratio mechanism, supercharging by the supercharging mechanism is not performed, and the detected required torque is greater than that of the first load region. In the second large load region, the valve timing of the intake valve is retarded by the variable valve mechanism, and the mechanical compression ratio of the internal combustion engine is increased by the variable compression ratio mechanism. When supercharging by a mechanism is performed and the detected required torque is in a third load region larger than the second load region, the valve closing timing of the intake valve is advanced by the variable valve mechanism. And an operation control means for lowering the mechanical compression ratio of the internal combustion engine by the variable compression ratio mechanism and performing supercharging by the supercharging mechanism.
[0014]
According to the control apparatus for an internal combustion engine according to the second aspect of the present invention, when the required torque is in the middle load region, the valve closing timing of the intake valve is delayed by the variable valve mechanism, and the internal combustion engine by the variable compression ratio mechanism. When the mechanical compression ratio of the engine is increased, the supercharging mechanism is operated to supply the compressed intake air into the cylinder of the internal combustion engine, and the required torque is in a high load region where the load is larger than the medium load region Advances the closing timing of the intake valve by the variable valve mechanism, lowers the mechanical compression ratio of the internal combustion engine by the variable compression ratio mechanism, operates the supercharging mechanism, and compresses the intake air compressed into the cylinder of the internal combustion engine Supply. Therefore, in an internal combustion engine that includes a variable compression ratio mechanism, a variable valve mechanism, and a supercharging mechanism, it is possible to improve the fuel efficiency in the middle load region and increase the output torque in the high load region.
[0015]
In the control apparatus for an internal combustion engine according to the second aspect of the present invention, when the operation control means shifts from the second load region to the third load region, the actual compression ratio of the internal combustion engine is kept constant. The variable valve mechanism and the variable compression ratio mechanism may be controlled so as to maintain the same. Further, the operation control means advances the valve closing timing of the intake valve by the variable valve mechanism, and lowers the mechanical compression ratio of the internal combustion engine by the variable compression ratio mechanism, so that the actual operation of the internal combustion engine is reduced. The compression ratio may be kept constant. In such a case, the second load region is substantially expanded, and the fuel efficiency can be improved.
[0016]
According to a third aspect of the present invention, there is provided a control device for an internal combustion engine having an intake valve for communicating or blocking the inside of a cylinder of the internal combustion engine and the atmosphere. A control apparatus for an internal combustion engine according to a third aspect of the present invention includes: a variable valve mechanism that changes a closing timing of the intake valve; a variable compression ratio mechanism that changes a mechanical compression ratio of the internal combustion engine; A supercharging mechanism for supplying compressed intake air into the cylinder of the internal combustion engine; a cooler for lowering the temperature of the compressed intake air introduced into the cylinder of the internal combustion engine from the supercharging mechanism; Requested torque detecting means for detecting required torque for the internal combustion engine, and the detected required torque is required to be larger than about half of the maximum torque output from the internal combustion engine when the supercharging mechanism is operated. In the high load range, the valve timing of the intake valve is advanced by the variable valve mechanism, the mechanical compression ratio of the internal combustion engine is lowered by the variable compression ratio mechanism, and the supercharging mechanism is By moving, characterized in that it comprises a driving control means for supplying the intake air compressed into the cylinder of the internal combustion engine.
[0017]
According to the control apparatus for an internal combustion engine according to the third aspect of the present invention, the detected required torque is greater than about half of the maximum torque output from the internal combustion engine when the supercharging mechanism is activated. When in the required high load region, the valve closing timing of the intake valve is advanced by the variable valve mechanism, the mechanical compression ratio of the internal combustion engine is lowered by the variable compression ratio mechanism, and the supercharging mechanism is operated to operate the internal combustion engine. Since the compressed intake air is supplied into the cylinder, the output torque can be increased in the high load region in the internal combustion engine including the variable compression ratio mechanism, the variable valve mechanism, and the supercharging mechanism.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a control device for an internal combustion engine according to the present invention will be described based on an embodiment with reference to the drawings.
[0019]
With reference to FIG. 1, a schematic configuration of the control apparatus for an internal combustion engine according to the present embodiment will be described. FIG. 1 is an explanatory diagram showing a schematic configuration of a control device for an internal combustion engine according to the present embodiment.
[0020]
The control apparatus for an internal combustion engine according to this embodiment includes an in-cylinder injection internal combustion engine, a control unit that controls the operation state of the internal combustion engine, and various sensors that detect the operation state of the internal combustion engine. The internal combustion engine 10 includes a cylinder block 12 having a plurality of cylinders 11 therein, a piston 13 reciprocating in the cylinder 11, a crankcase 14 disposed at the bottom of the cylinder block 12, and an upper portion of the cylinder block 12 (cylinder 11). A cylinder head 15 is provided.
[0021]
The internal combustion engine 10 in the present embodiment is provided with a variable compression ratio mechanism 20 that can arbitrarily set the mechanical compression ratio of the internal combustion engine 10 within a predetermined range. The variable compression ratio mechanism 20 changes the compression ratio by moving the cylinder block 12 with respect to the crankcase 14 in the movement direction of the piston 12 (the axial direction of the cylinder 11). Specifically, an eccentric cam (not shown) disposed on both sides in the longitudinal direction of the cylinder block 12 is driven by an actuator 21 (for example, a motor) provided on the cylinder block 12 side, and the cylinder block 12 is moved to the crankcase 14. Separate from or closely contact. The mechanical compression ratio is lowered by moving the cylinder block 12 away from the crankcase 14.
[0022]
The cylinder head 15 has an intake port 16 and an exhaust port 17 for each cylinder 11. Each intake port 16 is provided with an intake valve 161 that is driven by an intake side cam IC to open and close the intake port 16, and each exhaust port 17 is driven by an exhaust side cam EC to open and close the exhaust port 17. An exhaust valve 171 is disposed. In addition to this, a spark plug 31 for spark ignition is disposed in the cylinder head 15 at a position corresponding to each cylinder 11.
[0023]
In the intake side cam IC (intake side camshaft), the phase of the intake side camshaft with respect to the crankshaft is displaced, and the opening timing and closing timing of the intake valve 161 are delayed with respect to the normal timing (advance angle) ( A variable valve mechanism 25 (which retards) is provided. The variable valve mechanism 25 displaces the camshaft by an actuator 26 such as a motor or a hydraulic control valve. The variable valve mechanism 25 includes not only one that changes the valve timing but also one that changes the operating angle and the valve lift amount. In the present embodiment, any variable valve mechanism may be used as long as the closing timing of the intake valve 161 can be delayed. Further, the intake valve 161 may be directly driven by an actuator.
[0024]
Each intake port 16 is connected to a branch end of an intake pipe 18, and each exhaust port 17 is connected to a branch end of an exhaust pipe (exhaust manifold) 19. In the middle of the intake pipe 19, an intake control valve 30 for controlling the amount of intake air flowing into the combustion chamber is disposed.
[0025]
In the middle of the intake pipe 18 and the exhaust pipe 19, a supercharger 28 that compresses the intake air by an exhaust gas flow that flows through the exhaust pipe 19 is provided. The supercharger 28 is provided with a wastegate valve 281 that can set the supercharging pressure to an arbitrary value. When the wastegate valve 281 is opened, the exhaust gas bypasses the exhaust side turbine of the supercharger 28 and is released into the atmosphere, so the supercharger 28 does not operate. An intercooler (cooler) for cooling the supercharged intake air is disposed in the intake pipe 18 on the downstream side of the supercharger 28. The supercharger 28 includes not only one that compresses intake air by an exhaust gas flow, but also one that is mechanically driven by power from a crankshaft to compress intake air.
[0026]
Each intake port 16 is provided with a fuel injection valve IJ. That is, the internal combustion engine 10 used in this embodiment is a port injection type internal combustion engine. Each fuel injection valve IJ is supplied with fuel via a fuel delivery pipe FD.
[0027]
The control unit 40 has a storage function for storing arithmetic processing functions, maps, programs, and the like. The control unit 40 is connected to various sensors such as an accelerator position sensor 50 for detecting the depression amount of the accelerator pedal, a vehicle speed sensor 51 for detecting the vehicle speed, and a crank position sensor 52 for detecting the engine speed. Signals from various sensors that detect the operating state are input. The control unit 40 is connected to the fuel injection valve IJ, the actuator 21 of the variable compression ratio mechanism 20, the actuator 26 of the variable valve mechanism 25, the waste gate valve 281, the intake control valve 30, and the spark plug 31. 161 valve opening / closing timing, mechanical compression ratio, supercharging on / off, fuel injection timing, ignition timing, intake air amount, and the like are appropriately controlled.
[0028]
An internal combustion engine operation control process executed by the internal combustion engine control apparatus according to the present embodiment will be described with reference to FIGS. FIG. 2 is a flowchart showing a processing routine executed in the operation control processing of the internal combustion engine in the present embodiment. FIG. 3 is an explanatory diagram showing an example of a map for determining the load region of the internal combustion engine 10 based on the required torque and the engine speed. FIG. 4 is an explanatory diagram showing control conditions for each load set according to the determined load region. FIG. 5 is an explanatory view showing a change in the closing timing of the intake valve. FIG. 6 is an explanatory diagram illustrating a characteristic line representing the relationship between the fuel consumption rate and the torque in the low / medium / high load region, explaining the advantages of the present embodiment over the conventional control. FIG. 7 is an explanatory diagram showing a comparison of the fuel efficiency and torque between the present embodiment and the conventional control particularly in the middle load region. FIG. 8 is an explanatory diagram schematically showing changes in the compression ratio, mechanical compression ratio, and actual compression ratio according to the intake valve timing at the time of transition from the middle load region to the high load region in the present embodiment. is there.
[0029]
The operation control process of the internal combustion engine will be described with reference to FIG. This processing routine is repeatedly executed at predetermined time intervals. The control unit 40 detects the required torque based on the depression amount of the accelerator pedal detected by the accelerator position sensor 50 (step S100), and sets the calculated required torque and the engine speed detected from the crank position sensor as parameters. Then, the load area is determined from the map shown in FIG. 3 (step S110).
[0030]
When the control unit 40 determines that the operating load of the internal combustion engine 10 is in the low load region, the control unit 40 sets the compression ratio, the intake valve closing timing, and the supercharging state to the low load region conditions shown in FIG. S120). That is, the mechanical compression ratio is set high, the closing timing of the intake valve is retarded as shown in FIG. 5, and supercharging is not performed. The control unit 40 transmits a drive signal to the actuator 21 to bring the cylinder block 12 and the crankcase 14 into close contact with each other to increase the mechanical compression ratio, and transmits a drive signal to the actuator 26 to transmit the intake valve. The valve closing timing is retarded from the normal timing, and a driving signal is transmitted to the waste gate valve 281 to open the waste gate valve 281 (step S130).
[0031]
As a result, the pumping loss is reduced by the late closing of the intake valve 161, and the mechanical compression ratio is set high, so that it is possible to achieve a reduction in fuel consumption (reduction in fuel consumption) as shown in FIG.
[0032]
When the control unit 40 determines that the operating load of the internal combustion engine 10 is in the medium load region, the control unit 40 sets the compression ratio, the intake valve closing timing, and the supercharging state to the medium load region conditions shown in FIG. S140). That is, the mechanical compression ratio is set high, the closing timing of the intake valve is retarded as shown in FIG. 5, and supercharging is executed. The control unit 40 transmits a drive signal to the actuator 21 to bring the cylinder block 12 and the crankcase 14 into close contact with each other to increase the mechanical compression ratio, and transmits a drive signal to the actuator 26 to transmit the intake valve. The valve closing timing is retarded from the normal timing, a drive signal is transmitted to the waste gate valve 281 to close the waste gate valve 281 (step S150).
[0033]
In the control apparatus for an internal combustion engine according to the present embodiment, the mechanical compression ratio is set high in the medium load region, the intake valve 161 is closed late, and supercharging is performed (this embodiment: L1 in FIG. 6). Compared to the case where the compression ratio is set low, the intake valve 161 is closed early (normal timing), and supercharging is not executed (conventional control: L2 in FIG. 6), the fuel consumption rate is lowered (lower fuel consumption). You can plan. Note that the medium load region refers to, for example, a load region having a torque of about ½ of the maximum torque that the internal combustion engine 10 can output when the supercharger 28 is operated.
[0034]
That is, according to the present embodiment, since the degree of expansion is increased by setting the mechanical compression ratio high, the pressure obtained by the combustion of the air-fuel mixture is efficiently transmitted to the piston (reduction of combustion pressure loss). ), Fuel efficiency can be improved as compared with the case where the mechanical compression ratio is low. Further, since the intake air amount is reduced by the slow closing of the intake valve 161 as compared with the case where the intake valve 161 is closed at a normal timing (advance), the intake valve 161 is delayed as indicated by a black dot on the characteristic line L1 in FIG. Although only the angular torque can be output, the advance torque (L2 in FIG. 7) when the valve closing timing of the intake valve 161 is advanced by compensating for the reduced intake air amount by supercharging (L2 in FIG. 7). A torque similar to that of the middle black dot) can be obtained.
[0035]
In general, when the mechanical compression ratio is high, the occurrence of knocking due to supercharging becomes a problem. In this embodiment, the closing timing of the intake valve 161 is delayed by delaying the closing timing of the intake valve 161. Decrease the compression ratio (compression ratio until the piston 13 reaches the compression top dead center after the intake valve 161 is closed) determined by the timing, lower the actual compression ratio and increase the temperature of the mixture (intake) due to compression And the intake air compressed by the supercharger 28 is cooled by the intercooler 29. As a result, the rise of the mixture temperature before ignition is suppressed and knocking can be suppressed. The actual compression ratio means an actual compression ratio in the cylinder 11 determined by the closing timing of the intake valve 161 and the mechanical compression ratio.
[0036]
Therefore, the same torque as that obtained by the conventional control can be obtained with lower fuel consumption.
[0037]
When the control unit 40 determines that the operating load of the internal combustion engine 10 is in the high load region, the control unit 40 sets the compression ratio, the intake valve closing timing, and the supercharging state to the high load region conditions shown in FIG. S160). That is, the mechanical compression ratio is set low, the intake valve closing timing is advanced as shown in FIG. 5, and supercharging is executed. The control unit 40 transmits a drive signal to the actuator 21 to separate the cylinder block 12 and the crankcase 14 to lower the mechanical compression ratio, and transmits a drive signal to the actuator 26 to control the intake valve. The valve closing timing is changed to the advance timing that is the normal timing, a drive signal is transmitted to the waste gate valve 281 and the waste gate valve 281 is closed (step S170).
[0038]
When switching from the medium load region to the high load region, the control unit 40 switches the valve closing timing of the intake valve 161 (from retard to advance) and switches the mechanical compression ratio of the internal combustion engine 10 (from high to low). (Compression ratio) is executed at the same time, and the actual compression ratio at the time of transition from the medium load region to the high load region is kept constant as shown in FIG.
[0039]
In the control apparatus for an internal combustion engine according to the present embodiment, the mechanical compression ratio is set low in the high load region, the intake valve 161 is quickly closed, and supercharging is performed (this embodiment: L1 in FIG. 6). When the compression ratio is set low, the intake valve 161 is closed slowly (normal timing), and supercharging is performed (conventional control: L2 in FIG. 6), the fuel efficiency is lowered (lower fuel consumption). A larger torque can be obtained.
[0040]
That is, in the conventional control, since the closing timing of the intake valve 161 is retarded, further output torque is obtained by the supercharger from the retarded time torque indicated by a black dot on L3 in FIG. 7 (L3 in FIG. 7). Therefore, the reachable output torque was small. On the other hand, in this embodiment, as shown by the characteristic line L4 in FIG. 7, the closing timing of the intake valve 161 is advanced (normal timing). Torque (medium black point on the characteristic line L4) can be obtained, and a larger torque can be obtained by using the supercharger.
[0041]
When the execution of the condition according to the load condition is completed, the control unit 40 executes the operation control of the internal combustion engine 10 under the executed condition (Step S180), and ends this processing routine. Specifically, the valve opening angle control, the fuel injection timing control, and the ignition timing control of the intake valve 30 are executed according to the operating state (load) of the internal combustion engine 10.
[0042]
As described above, according to the control apparatus for an internal combustion engine according to the present embodiment, the mechanical compression ratio is set high in the middle load region, the intake valve 161 is closed slowly, and supercharging is executed. In comparison, the fuel efficiency in the middle load region can be improved. Further, in the high load region, the mechanical compression ratio is set low, the intake valve 161 is quickly closed, and supercharging is executed. Therefore, the output torque can be increased at a fuel consumption rate equivalent to that of the conventional control.
[0043]
In addition, according to the control apparatus for an internal combustion engine according to the present embodiment, the actual compression ratio at the time of transition from the medium load region to the high load region is kept constant, so that it is possible to expand the substantially medium load region, and the compression The fuel consumption resulting from the ratio can be improved.
[0044]
Other examples:
In the above embodiment, the variable compression ratio mechanism 20 has been described by taking the cylinder expansion / contraction type in which the cylinder block 12 moves with respect to the crankcase 14 as an example, but in addition, for example, a joint portion is provided in the middle of the piston connecting rod. An intermediate folding connecting rod type that changes the top dead center position of the piston may be used. That is, if it is a variable compression mechanism provided with a mechanism capable of changing the mechanical compression ratio (geometric compression ratio) of the internal combustion engine 10, the fuel efficiency in the medium load region is combined with the variable valve mechanism 25 and the supercharger 28 according to the above embodiment. Effects such as improved performance and increased output torque in a high load region can be obtained.
[0045]
As described above, the control apparatus for an internal combustion engine according to the present invention has been described based on some examples. However, the above-described embodiments of the present invention are for facilitating the understanding of the present invention. It is not limited. The present invention can be changed and improved without departing from the spirit and scope of the claims, and it is needless to say that the present invention includes equivalents thereof.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a schematic configuration of a control device for an internal combustion engine according to an embodiment.
FIG. 2 is a flowchart showing a processing routine executed in an operation control process of the internal combustion engine in the present embodiment.
FIG. 3 is an explanatory diagram showing an example of a map for determining a load region of the internal combustion engine 10 based on a required torque and an engine speed.
FIG. 4 is an explanatory diagram showing load-specific control conditions set in accordance with a determined load region.
FIG. 5 is an explanatory diagram showing a change in the closing timing of the intake valve.
FIG. 6 is an explanatory diagram showing a characteristic line representing a relationship between a fuel consumption rate and a torque in a low / medium / high load region, explaining advantages of the present embodiment over conventional control.
FIG. 7 is an explanatory diagram showing a comparison between fuel efficiency and torque between the present embodiment and conventional control, particularly in a middle load region.
FIG. 8 is an explanatory diagram schematically showing changes in compression ratio, mechanical compression ratio, and actual compression ratio according to the intake valve timing at the time of transition from the middle load region to the high load region in the present embodiment. It is.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine 11 ... Cylinder 12 ... Cylinder block 13 ... Piston 14 ... Crankcase 15 ... Cylinder head 16 ... Intake port 161 ... Intake valve 17 ... Exhaust port 171 ... Exhaust valve 18 ... Intake pipe 19 ... Exhaust pipe 20 ... Variable compression Ratio mechanism 21 ... Actuator 25 ... Variable valve mechanism 26 ... Actuator 28 ... Supercharger 281 ... Wastegate valve 29 ... Intercooler 30 ... Intake control valve 31 ... Booster pump 32 ... Spark plug 40 ... Control unit 50 ... Accelerator opening sensor 51 ... Speed sensor 52 ... Crank position sensor IC ... Intake side cam EC ... Exhaust side cam IJ ... Fuel injection valve (injector)
FD ... Fuel delivery pipe

Claims (5)

A control device for an internal combustion engine having an intake valve for communicating or blocking the inside of a cylinder of the internal combustion engine and the atmosphere,
A variable valve mechanism for changing the closing timing of the intake valve;
A variable compression ratio mechanism for changing the mechanical compression ratio of the internal combustion engine;
A supercharging mechanism for supplying compressed intake air into the cylinder of the internal combustion engine;
A required torque detecting means for detecting a required torque for the internal combustion engine;
When the detected required torque is in an intermediate load region, the variable valve mechanism delays the closing timing of the intake valve, the variable compression ratio mechanism increases the mechanical compression ratio of the internal combustion engine, When the supercharging mechanism is operated to supply compressed intake air into the cylinder of the internal combustion engine and the detected required torque is in a high load region where the load is larger than the medium load region, the allowable The intake valve compressed by the variable valve mechanism advances the closing timing of the intake valve, lowers the mechanical compression ratio of the internal combustion engine by the variable compression ratio mechanism, and activates the supercharging mechanism to be compressed into the cylinder of the internal combustion engine. to supply the air, when moving to the front Symbol high load region from the medium load region, and controls the variable valve mechanism and the variable compression ratio mechanism to keep the actual compression ratio of the internal combustion engine constant luck Operation control apparatus for an internal combustion engine and a control unit. The control apparatus for an internal combustion engine according to claim 1 further includes:
A control apparatus for an internal combustion engine, comprising a cooler for reducing the temperature of compressed intake air introduced into the cylinder of the internal combustion engine from the supercharging mechanism.   3. The control device for an internal combustion engine according to claim 1, wherein in the intermediate load region, a torque that is approximately ½ of a maximum torque output by the internal combustion engine when the supercharging mechanism is operated is required as a required torque. The control apparatus of the internal combustion engine which is a load area | region to be performed. A control device for an internal combustion engine,
A supercharging mechanism;
A variable valve mechanism that changes at least the closing timing of the intake valve; and
A variable compression ratio mechanism for changing the mechanical compression ratio of the internal combustion engine;
A required torque detecting means for detecting a required torque for the internal combustion engine;
When the detected required torque is in a low load region, the valve closing timing of the intake valve is retarded by the variable valve mechanism, and the mechanical compression ratio of the internal combustion engine is adjusted by the variable compression ratio mechanism. And when the detected required torque is in a medium load region that is larger than the low load region, the valve timing of the intake valve is closed by the variable valve mechanism. Is retarded, the mechanical compression ratio of the internal combustion engine is increased by the variable compression ratio mechanism, the supercharging is performed by the supercharging mechanism, and the detected required torque is set to a high load region larger than the medium load region. In some cases, the valve timing of the intake valve is advanced by the variable valve mechanism, the mechanical compression ratio is lowered to the internal combustion engine by the variable compression ratio mechanism, and supercharging is performed by the supercharging mechanism. in front Control of the internal combustion engine comprising the variable valve mechanism and the operation control means for controlling the variable compression ratio mechanism so as to keep the actual compression ratio of the internal combustion engine constant when shifting from the middle load region to the high load region apparatus. The control apparatus for an internal combustion engine according to claim 4,
The operation control means advances the valve closing timing of the intake valve by the variable valve mechanism, and lowers the mechanical compression ratio of the internal combustion engine by the variable compression ratio mechanism, thereby reducing the actual compression ratio of the internal combustion engine. A control device for an internal combustion engine that keeps constant.

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