JP2006283659A - Intake control device and its method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intake control device and its method, capable of forming a swirl in a combustion chamber in response to an operation state of a vehicle, in an engine for arranging an intake control valve for opening and closing in response to the opening-closing timing of an intake valve for increasing an intake quantity. <P>SOLUTION: This intake control device has the intake control valve 30 capable of opening and closing an intake passage 14 in response to the opening-closing timing of the intake valve 25, and operation state detecting means 34 to 36 and 40 for detecting the operation state of an engine 10; and also has a control device 21 having a request swirl ratio deriving part for deriving the request swirl ratio to be formed in a combustion chamber 12 in response to the operation state of the engine 10, an actual swirl deriving part for deriving the actual swirl ratio actually formed in the combustion chamber 12 on the basis of a detecting signal from the operation state detecting means 34 to 36 and 40, and an opening-closing timing setting part for setting the opening-closing timing of the intake control valve 30 so that the actual swirl ratio becomes equal to the request swirl ratio; and is controlled by the control device 21 so that the intake control valve 30 is opened and closed in the preset opening-closing timing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an intake control device provided with an intake control valve capable of opening and closing an intake passage according to the opening and closing timing of the intake valve, and a method thereof.

  Pulse supercharging incorporates an on-off valve that operates at a very high speed in the intake passage upstream of the intake valve, and opens the on-off valve later than this in synchronization with the opening timing of the intake valve. Supercharging is performed using the negative pressure generated in the intake passage and the combustion chamber on the downstream side of the on-off valve and the inertia of the intake air, and Patent Document 1 shows an example of the configuration of the on-off valve. Is disclosed.

  On the other hand, as a measure for purifying the exhaust gas, it is effective to form a swirl flow (swirl) in the intake air sucked into the combustion chamber and make the mixing with the fuel uniform. In an engine having two or more intake ports and intake valves, a helical intake port having a passage in which intake air forms a swirl flow in the same direction as the swirl direction of the intake swirl formed in the combustion chamber And a tangential intake port formed with a passage through which intake air flows along the tangential direction of the inner peripheral wall of the combustion chamber are used in appropriate combination so that a desired swirl ratio can be obtained.

  In order to purify the exhaust gas, it is common to adsorb particulate matter (PM) containing carbon or carbide contained in the exhaust gas to the catalyst. However, fuel is periodically supplied to the catalyst. Thus, PM is combusted so that the function of the catalyst does not deteriorate. In this case, what performs a post-injection process in which fuel is injected into the combustion chamber from the fuel injection valve facing the combustion chamber after the expansion stroke and supplied to the catalyst is known. In particular, in a compression ignition engine such as a diesel engine, in order to eliminate the clogging of the catalyst that cannot be prevented only by the post-injection process, a catalyst post-process for supplying a larger amount of fuel to the catalyst and regenerating it. That is, it is necessary to perform catalyst regeneration treatment.

JP 2000-248946 A Japanese Patent Publication No. 6-63453

  In the conventional pulse supercharging described above, the opening timing of the intake control valve is set so that the intake amount is always maximized, but the swirl ratio is more important than the intake amount depending on the driving state of the vehicle. There are also many.

  For example, in a region where the engine speed is low, there is sufficient time for mixing fuel and air supplied to the combustion chamber, so it is desirable to increase the swirl ratio to form a more uniform mixture. However, when pulse supercharging is performed in a region where the engine speed is low, the suction period is short, so that swirl formation is hindered and smoke may be generated. Such a problem is likely to occur particularly when the vehicle is accelerated in a region where the engine speed is low. Conversely, in a region where the engine speed is high, the time until fuel combustion is completed is relatively short. Therefore, if the swirl ratio increases, the fuel does not burn out and smoke is generated. Therefore, it is necessary to reduce the swirl ratio in a region where the engine speed is high.

  Such a problem also occurs when an exhaust gas recirculation (EGR) device is operated and a part of the exhaust gas is taken into the intake air. In other words, when part of the exhaust gas is taken into the intake air in the low load region of the engine to reduce the amount of nitrogen oxides in the exhaust gas, the formation of swirl is hindered by performing pulse supercharging, It becomes difficult to mix the exhaust gas uniformly, and the reduction effect of nitrogen oxides becomes low.

  On the other hand, in the post-injection process in which fuel is injected from the fuel injection valve after the expansion stroke of the engine and this is supplied to the catalyst, the fuel injection timing is the time when the pressure in the combustion chamber decreases, If sufficient swirl is not formed, bore flashing occurs in which the fuel does not vaporize but adheres to the inner wall of the combustion chamber and the like and peels off the lubricating oil film. In the worst case, engine burn-in occurs.

  Thus, when performing pulse supercharging, it is necessary to consider a swirl ratio according to the driving | running state of a vehicle.

  An object of the present invention is to provide an intake air in which a swirl according to the operating state of a vehicle can be formed in a combustion chamber in an engine provided with an intake control valve that opens and closes according to the opening and closing timing of the intake valve in order to increase the intake air amount. A control device and a method thereof are provided.

  According to a first aspect of the present invention, an intake control valve that is provided in an intake passage and can open and close the intake passage according to the opening and closing timing of the intake valve, an operating state detecting means that detects an operating state of the engine, and the operating state An intake control device comprising control means for controlling opening and closing of the intake control valve based on a detection signal from the detection means, wherein the control means is configured to detect the engine based on the detection signal from the operating state detection means. An operating state determining unit that determines whether or not the engine is in a predetermined operating state, and when the operating state determining unit determines that the engine is in a predetermined operating state, the engine is formed in the combustion chamber according to the operating state of the engine. A required swirl ratio deriving unit for deriving a required swirl ratio to be calculated, and a real swirl ratio deriving for deriving an actual swirl ratio that is actually formed in the combustion chamber based on a detection signal from the operating state detection means And opening / closing timing setting for setting the opening / closing timing of the intake control valve so that the actual swirl ratio derived by the actual swirl ratio deriving unit is equal to the required swirl ratio derived by the required swirl ratio deriving unit And the opening / closing of the intake control valve is controlled so as to be the opening / closing timing set by the opening / closing timing setting unit.

  In the present invention, based on the detection signal from the driving state detection means, the driving state determination unit determines whether or not the engine is in a predetermined driving state. Here, when the operating state determination unit determines that the engine is in a predetermined operating state, the required swirl ratio deriving unit derives a required swirl ratio to be formed in the combustion chamber according to the operating state of the engine, while The swirl ratio deriving unit derives the actual swirl ratio that is actually formed in the combustion chamber based on the detection signal from the operating state detecting means. Then, the opening / closing timing of the intake control valve is set by the opening / closing timing setting unit so that the actual swirl ratio derived by the actual swirl ratio deriving unit becomes equal to the required swirl ratio derived by the required swirl ratio deriving unit. Then, the opening and closing of the intake control valve is controlled by the control means so that the opening / closing timing set by the opening / closing timing setting unit is reached.

  The intake control device according to the first aspect of the present invention further includes an intake pressure sensor for detecting an intake pressure in an intake passage between the intake valve and the intake control valve, and the control means detects a detection signal from the intake pressure sensor. Based on the above, the initial intake amount deriving unit for deriving the intake amount filled in the intake passage between the intake valve and the intake control valve in the closed state, and the opening / closing timing setting of the intake control valve by the opening / closing timing setting unit Is an opening / closing frequency determination unit that determines whether or not the intake control valve has been opened or closed for the second time or later, and the opening / closing timing setting of the intake control valve is determined by the intake control valve. When the opening / closing control of the engine is determined to be the second or later time, the opening / closing timing of the intake control valve set by the opening / closing timing setting unit is set according to the intake amount derived by the initial intake amount deriving unit. And an open / close timing correction unit for correction. It may be.

  The predetermined operating state is an engine acceleration state, an EGR operation state, a post-injection process for burning PM adhering to the catalyst, or a catalyst regeneration process for supplying fuel during regeneration of the catalyst in the compression ignition engine. It's okay.

  The intake control device according to the first aspect of the present invention further includes an actual air amount deriving unit for deriving an air amount actually introduced into the combustion chamber, and the control unit is introduced into the combustion chamber according to a predetermined operating state. A required air amount deriving unit for deriving a minimum air amount to be obtained, and when the engine is in a predetermined operating state, the control means derives the required air amount from the actual air amount deriving means; The amount of air flowing into the combustion chamber may be controlled so as to be the required amount of air derived by the section. When the predetermined operation state is the EGR operation state, the control means communicates with the intake passage between the intake control valve and the intake valve and controls the EGR control provided in the EGR passage that guides a part of the exhaust gas into the intake passage. By controlling the opening and closing of the valve, the amount of air flowing into the combustion chamber can be controlled.

  The control means further includes a minimum swirl ratio deriving unit for deriving a minimum swirl ratio at which the air-fuel mixture can normally burn in the combustion chamber based on a detection signal from the operation state detecting means, When the operating state determination unit determines that the engine is not in a predetermined operating state, the actual swirl ratio derived by the actual swirl ratio deriving unit is equal to the minimum swirl ratio derived by the minimum swirl ratio deriving unit The opening / closing timing of the intake control valve may be set.

  According to a second aspect of the present invention, a plurality of intake valves for opening and closing a plurality of intake ports respectively communicating with one combustion chamber and a ratio of intake air flowing through the plurality of intake ports are formed in the combustion chamber. A swirl control valve that can change the swirl ratio of the intake air, an intake control valve that is provided in the intake passage upstream of the swirl control valve and that can open and close the intake passage according to the opening and closing timing of the intake valve, and the engine An intake control device comprising: an operation state detection unit that detects an operation state; and a control unit that controls opening and closing of the swirl control valve and the intake control valve based on a detection signal from the operation state detection unit. The control means includes a required swirl ratio deriving unit for deriving a required swirl ratio to be formed in the combustion chamber based on a detection signal from the operating condition detecting means, and the operating condition The actual swirl ratio deriving unit for deriving the swirl ratio of the intake air actually formed in the combustion chamber based on the detection signal from the output means, and the actual swirl ratio derived by the actual swirl ratio deriving unit is the required swirl ratio. An opening setting unit for setting the opening of the swirl control valve so as to be equal to the required swirl ratio derived by the deriving unit, and an opening timing of the intake control valve for obtaining the maximum intake amount And a valve opening timing setting section to be set.

  In the present invention, the required swirl ratio deriving unit derives the required swirl ratio to be formed in the combustion chamber based on the detection signal from the operating state detecting means, while the actual swirl ratio deriving unit is actually formed in the combustion chamber. The intake air swirl ratio is derived. The opening setting unit sets the opening of the swirl control valve so that the actual swirl ratio derived by the actual swirl ratio deriving unit is equal to the required swirl ratio derived by the required swirl ratio deriving unit. On the other hand, the valve opening timing of the intake control valve is set by the valve opening timing setting section so that the maximum intake amount can be obtained. The control means controls the operation of the swirl control valve so that the opening of the swirl control valve becomes the opening set by the opening setting unit, while the valve opening timing set by the valve opening timing setting unit The opening timing of the intake control valve is controlled so that

  According to a third aspect of the present invention, there is provided an intake control valve for an engine provided with an intake control valve capable of opening and closing an intake passage in accordance with the opening and closing timing of the intake valve, the step of detecting the operating state of the engine, A step for determining whether the engine operating state is in a predetermined operating state, and a request to be formed in the combustion chamber according to the engine operating state when it is determined that the engine is in the predetermined operating state A step of deriving a swirl ratio, a step of deriving an actual swirl ratio that is actually formed in the combustion chamber in accordance with the detected operating state of the engine, and a derived actual swirl ratio equal to the derived required swirl ratio And a step of setting the opening / closing timing of the intake control valve and a step of controlling the opening / closing of the intake control valve so as to be the set opening / closing timing. It is intended to.

  In the intake control method according to the third aspect of the present invention, the step of detecting the intake pressure in the intake passage, and the intake passage between the intake valve and the intake control valve in the closed state based on the detected intake pressure A step of deriving an intake air amount to be filled in, a step of determining whether or not the setting of the opening / closing timing of the intake control valve is the second or later time after starting the opening / closing control of the intake control valve, A step of correcting the set opening / closing timing of the intake control valve according to the derived intake air amount when it is determined that the setting of the opening / closing timing of the valve is the second or later time after starting the opening / closing control of the intake control valve; Can further be included.

  According to the intake control apparatus of the first aspect of the present invention, the control means determines whether or not the engine is in a predetermined operation state based on the detection signal from the operation state detection means, and this operation When the state determination unit determines that the engine is in a predetermined operating state, a required swirl ratio deriving unit that derives a required swirl ratio to be formed in the combustion chamber according to the predetermined operating state, and an operating state detection The actual swirl ratio deriving unit for deriving the swirl ratio of the intake air actually formed in the combustion chamber based on the detection signal from the means, and the actual swirl ratio derived by the actual swirl ratio deriving unit is the required swirl ratio deriving unit And an opening / closing timing setting section for setting the opening / closing timing of the intake control valve so as to be equal to the required swirl ratio derived in step S1, and the intake air is set so as to be the opening / closing timing set by the opening / closing timing setting section. Since the opening and closing of the control valve is controlled, an appropriate swirl according to the driving state of the vehicle can be formed in the combustion chamber in combination with the increase of the intake air amount by the intake control valve, and the occurrence of smoke etc. It can be prevented in advance.

  An initial intake amount deriving unit for deriving an intake amount filled in an intake passage between the intake valve and the intake control valve in a closed state based on a detection signal from the intake pressure sensor; An opening / closing number determination unit for determining whether or not the setting of the opening / closing timing of the intake control valve by the setting unit is the second or subsequent time after the start of the opening / closing control of the intake control valve, and the intake control at the opening / closing number determination unit If it is determined that the opening / closing timing of the valve is set to be the second or later time after starting the opening / closing control of the intake control valve, the opening / closing timing of the intake control valve set by the opening / closing timing setting unit is derived. And an opening / closing timing correction unit that corrects the intake amount derived in accordance with the intake amount derived from the intake portion, expecting the intake amount to be filled in the intake passage between the intake valve and the intake control valve in the closed state When opening and closing the intake control valve set in the opening / closing timing setting section More precisely can be corrected, whereby it is possible to form an accurate swirl the combustion chamber, it is possible to more reliably prevent well as smoke generation.

  The control means further includes a required air amount deriving unit for deriving a minimum air amount to be introduced into the combustion chamber in accordance with a predetermined operating state, and in the predetermined operating state of the engine, the control means When controlling the amount of air flowing into the combustion chamber so that the amount of air derived by the air amount deriving means becomes the required amount of air derived by the required amount of air deriving unit, the predetermined operating state is particularly the EGR operating state. The control means controls the opening and closing of the EGR control valve provided in the EGR passage that communicates with the intake passage between the intake control valves and guides a part of the exhaust gas into the intake passage. Thus, when the amount of air flowing into the combustion chamber is controlled, an appropriate EGR amount corresponding to the driving state of the vehicle can be maintained, and the exhaust gas can be cleaned without difficulty.

  The control means further has a minimum swirl ratio deriving unit for deriving a minimum swirl ratio at which the air-fuel mixture can normally burn in the combustion chamber based on the detection signal from the operating state detecting unit, and the engine in the operating state determining unit Is determined so that the actual swirl ratio derived by the actual swirl ratio deriving unit is equal to the minimum swirl ratio derived by the minimum swirl ratio deriving unit. When the opening / closing timing of the control valve is set, it is possible to form a minimum swirl required in accordance with the driving state of the vehicle in the combustion chamber, and it is possible to reliably prevent the occurrence of smoke.

  According to the intake control device of the second aspect of the present invention, the control means derives a required swirl ratio deriving unit that derives a required swirl ratio to be formed in the combustion chamber based on a detection signal from the operating state detecting means; Based on the detection signal from the operating state detection means, the actual swirl ratio deriving unit for deriving the swirl ratio of the intake air actually formed in the combustion chamber, and the actual swirl ratio derived by the actual swirl ratio deriving unit is the required swirl Set the opening setting part to set the opening of the swirl control valve to be equal to the required swirl ratio derived by the ratio deriving part, and the opening timing of the intake control valve to obtain the maximum intake amount Since the control device has the valve opening timing setting section that performs this, a swirl according to the operating state of the vehicle can be formed in the combustion chamber in a state where the intake air amount is maximized by the intake control valve.

  According to the intake control method of the third aspect of the present invention, the operating state of the engine is detected, it is determined whether or not the detected operating state of the engine is in a predetermined operating state, and the engine is brought into a predetermined operating state. If it is determined that there is, the required swirl ratio to be formed in the combustion chamber according to the engine operating state is derived, and the actual swirl ratio actually formed in the combustion chamber according to the detected engine operating state is derived. The intake control valve is set to open and close so that the actual swirl ratio is equal to the required swirl ratio, so that the opening and closing of the intake control valve is controlled. An appropriate swirl according to the operating state can be formed in the combustion chamber, and the occurrence of smoke can be prevented in advance.

  An embodiment in which the intake control device according to the present invention is applied to a diesel engine that is a compression ignition engine will be described in detail with reference to FIGS. 1 to 10, but the present invention is not limited to such an embodiment. All changes and modifications that fall within the inventive concept described in the claims are possible, and can of course be applied to any other technique belonging to the spirit of the present invention.

  The concept of the engine system in this embodiment is shown in FIG. 1, the schematic structure of the intake port portion is shown in FIG. 2, and the control block in this engine system is shown in FIG. The engine 10 according to the present embodiment is of a type that spontaneously ignites by directly injecting light oil, which is fuel, into the combustion chamber 12 in a compressed state from the fuel injection valve 11. An exhaust gas recirculation (EGR) device 15 that guides a part of the exhaust gas flowing in the intake passage 14 is incorporated. The EGR device 15 has an EGR pipe defining an EGR passage 18 having one end communicating with an exhaust passage 13 defined by an exhaust pipe 16 and the other end communicating with an intake passage 14 defined by an intake pipe 17. 19 and an EGR control valve 20 provided in the EGR pipe 19 for controlling the flow rate of exhaust gas flowing in the EGR passage 18. The opening degree of the EGR control valve 20 is controlled by the control device 21 according to the driving state of the vehicle when the vehicle on which the engine 10 is mounted is in a preset EGR driving region, and otherwise the basic operation is performed. The EGR passage 18 is kept closed so as to close the EGR passage 18.

  An intake valve 25 and an exhaust port 23 for opening and closing the intake port 22 are provided in a cylinder head 24 formed with intake ports 22H and 22T (hereinafter may be simply referred to as 22) and exhaust ports 23 respectively facing the combustion chamber 12. A valve operating mechanism (not shown) including an exhaust valve 26 that opens and closes the intake valve 25 and the fuel injection valve 11 that faces the center of the upper end of the combustion chamber 12 so as to be sandwiched between the intake valve 25 and the exhaust valve 26 are incorporated. In this embodiment, the intake port 22 is a helical intake having a passage that forms a swirl flow of the intake air in the same direction as the swirl direction of the intake swirl formed in the combustion chamber 12 (right rotation direction in FIG. 2). Each combustion chamber 12 has a port 22 </ b> H and a tangential intake port 22 </ b> T that forms a passage through which intake air flows along the tangential direction of the inner peripheral wall of the combustion chamber 12. It is also possible to configure these with only the helical intake port 22H or only the tangential intake port 22T as required. The valve mechanism in the present embodiment is such that the opening and closing timings of the intake valve 25 and the exhaust valve 26 are always fixed regardless of the operating state of the engine 10. The opening / closing timing of the valve 25 and the exhaust valve 26 may be changed.

  At the upstream end side of the intake pipe 17 which is connected to the cylinder head 24 so as to communicate with the intake port 22 and defines the intake passage 14 together with the intake port 22, dust contained in the atmosphere is removed to remove the intake passage 14. An air cleaner 27 is provided for guiding the air. The other end of the EGR pipe 19 described above is connected to a portion of the intake pipe 17 between the intake valve 25 and a surge tank 28 formed in the middle of the intake pipe 17. An intake control valve 30 that can open and close the intake passage 14 by an actuator 29 at a predetermined timing according to the opening and closing timing of the intake valve 25 is incorporated in the middle of the intake pipe 17.

  In the present embodiment, the portion of the intake pipe 17 from the surge tank 28 to the cylinder head 24 defines two intake passages 14 so as to communicate with the helical intake port 22H and the tangential intake port 22T, respectively. is doing. That is, the intake control valve 30 is provided independently for each of the helical intake port 22H and the tangential intake port 22T, and these intake ports 22 can be individually opened and closed. The intake control valve 30 and its actuator 29 have extremely high control responsiveness so that the intake control valve 30 opens and closes accurately at a desired timing according to the opening and closing timing of the intake valve 25.

  In the present embodiment, the intake control valve 30 is based on the operating state of the vehicle and takes into account the swirl formed in the combustion chamber 12, for example, in the low-rotation high-load operation region of the engine 10 than the opening timing of the intake valve 25. The control device 21 opens slowly and closes in accordance with the closing timing of the intake valve 25, but basically remains in a fully open state regardless of the opening / closing operation of the intake valve 25 in other operating regions. The opening / closing state is controlled by the actuator 29 based on the command from As a result, in the low-rotation and high-load operation region of the engine 10, the air in the intake passage 14 located upstream of the intake control valve 30 in the combustion chamber 12 that is in a negative pressure state until the middle of the intake stroke of the engine 10. Can flow at once, and a large amount of air can be filled into the combustion chamber 12 by a kind of inertial supercharging effect. In other words, in the supercharging using the intake control valve 30, actual supercharging is performed immediately after the start of control using the inertia of the intake air and the negative pressure generated downstream of the intake control valve 30. The Rukoto. Therefore, the control response is superior to that of the turbo supercharging system, and so-called acceleration delay of the vehicle can be eliminated. The basic technology related to the intake control valve 30 is described in detail in "Impulses for Greater Driving Fun" which was announced on September 9 by Siemens VDO Automotive AG at the 2003 Frankfurt Motor Show. .

  The fuel injection valve 11 in the present embodiment is a single injection type that injects light oil as fuel into the combustion chamber 12 only in the vicinity of the compression top dead center of the piston 31. In addition to fuel injection in this compression stroke, In order to form a more uniform air-fuel mixture, it is also possible to employ a multi-injection type that injects before the intake control valve 30 is opened in the intake stroke.

  In the middle of the exhaust pipe 16 connected to the cylinder head 24 so as to communicate with the inside of the combustion chamber 12 and defining the exhaust passage 13 together with the exhaust port 23, harmful substances generated by combustion of the air-fuel mixture in the combustion chamber 12 A catalyst 32 for detoxifying is incorporated. As this catalyst 32, not only a general oxidation catalyst in a diesel engine but also a DPF (Diesel Particulate-NOx Reduction System) or DPF (Diesel Particulate Filter) used for DPR (Diesel Particulate-NOx Reduction System) or the like may be adopted. Is possible. Therefore, DPR or DPNR can be incorporated in place of the catalyst 32. Note that one end of the EGR pipe 19 described above is connected to the exhaust pipe 16 on the upstream side of the catalyst 32.

  Accordingly, the intake gas supplied from the intake pipe 17 into the combustion chamber 12 through the air cleaner 27 together with the exhaust gas recirculated into the intake pipe 17 through the EGR pipe 19 is injected from the fuel injection valve 11 into the combustion chamber 12. An air-fuel mixture is formed with the fuel to be combusted, and is spontaneously ignited and combusted in the vicinity of the compression top dead center of the piston 31, and the exhaust gas generated thereby is exhausted from the exhaust pipe 16 to the atmosphere through the catalyst 32. In this case, the combustion temperature of the air-fuel mixture decreases due to the CO2 in the intake air supplied by the operation of the EGR device 15, so that the generation of nitrogen oxides due to the combustion of the air-fuel mixture is suppressed.

  In the present embodiment, the controller 21 grasps the operating state of the engine 10 and the vehicle on which the engine 10 is mounted, and the control device 21 determines the fuel injection amount and injection timing from the fuel injection valve 11, the opening degree of the EGR control valve 20, and In order to control the operation of the intake control valve 30, various sensors as described below are provided. That is, the accelerator opening sensor 34 that detects the amount of depression of the accelerator pedal 33 operated by the driver and outputs the detected amount to the control device 21, and the vehicle speed that detects the traveling speed of the vehicle and outputs this to the control device 21. And a sensor 35. An intake pressure sensor 36 that detects the intake pressure in the intake passage 14 and outputs it to the control device 21 is attached in the middle of the intake passage 14 between the intake valve 25 and the intake control valve 30. Yes. The intake pressure sensor 36 functions as part of the actual air amount deriving means of the present invention for deriving the actual air amount introduced into the combustion chamber 12. The attachment position of the intake pressure sensor 36 with respect to the intake pipe 17 may be any position downstream of the attachment position of the intake control valve 30, and is not limited to the position shown in FIG. Further, the cylinder block 37 in which the piston 31 reciprocates is detected by detecting the rotational phase of the crankshaft 39 to which the piston 31 is connected via the connecting rod 38, that is, the crank angle and outputting it to the control device 21. A sensor 40 is attached, which is also used as an engine speed sensor in the present embodiment.

  Based on the detection signals from these sensors 34 to 36, 40, etc., the control device 21 controls the fuel injection valve 11, the EGR control valve 20, and the intake air control so that the engine 10 can be smoothly operated according to a preset program. The operation of the valve 30 and the like is controlled.

  The control device 21 in the present embodiment includes a fuel injection amount setting unit 41 that sets the fuel injection amount from the fuel injection valve 11 based on the driving state of the vehicle, and the fuel set by the fuel injection amount setting unit 41. An injection timing setting unit 42 that sets the fuel injection timing corresponding to the injection amount, an operation state determination unit 43 that determines whether or not the vehicle is in a predetermined operation state, and the operation state determination unit 43 that uses the engine 10 Is determined to be in a predetermined operating state, a required swirl ratio deriving unit 44 for deriving a required swirl ratio to be formed in the combustion chamber 12 according to the operating state of the engine 10, and the operating state of the vehicle Based on the actual swirl ratio deriving unit 45 for deriving the actual swirl ratio actually formed in the combustion chamber 12 based on this, the actual swirl ratio derived by the actual swirl ratio deriving unit 45 is supplied to the required swirl ratio deriving unit 44. Based on the detection signal from the open / close timing setting unit 46 for setting the open / close timing of the intake control valve 30 and the intake pressure sensor 36 so as to be equal to the derived required swirl ratio, the intake valve 25 in the closed state and the intake valve The setting of the opening / closing timing of the intake control valve 30 by the opening / closing timing setting unit 46 by the initial intake amount derivation unit 47 for deriving the intake amount filled in the intake passage 14 between the intake valve 14 and the control valve 30 An open / close count determination unit 48 that determines whether or not the second or subsequent time has elapsed since the start of the open / close control, and the open / close count determination unit 48 sets the open / close timing of the intake control valve 30. When it is determined that it is the second or later time after the control is started, the opening / closing timing of the intake control valve 30 set by the opening / closing timing setting unit 46 is determined according to the intake air amount derived by the initial intake air amount deriving unit 47. To compensate for opening and closing 49, an actual air amount deriving unit 50 for deriving the actual air amount introduced into the combustion chamber 12 based on the detection signal from the intake pressure sensor 36, and the combustion chamber 12 according to a predetermined operating state. A required air amount deriving unit 51 for deriving a minimum air amount to be introduced, and a minimum swirl ratio deriving unit 52 for deriving a minimum swirl ratio at which the air-fuel mixture can normally burn in the combustion chamber 12 are provided. .

  The fuel injection amount setting unit 41 in the present embodiment has a map (not shown) relating to the fuel injection amount that is set in advance according to the accelerator opening, the vehicle speed, and the like, and from the accelerator opening sensor 34 and the vehicle speed sensor 35. Based on the detection signal, the driving torque of the engine 10, that is, the fuel injection amount from the fuel injection valve 11 is read from this map, and this is output to the injection timing setting unit 42. As is well known, since the fuel injection amount is synonymous with the engine load, the engine load may be calculated instead of setting the fuel injection amount.

  The injection timing setting unit 42 sets the injection timing so that the fuel injection set by the fuel injection amount setting unit 41 is completed by the vicinity of the compression top dead center of the piston 31.

  The driving state determination unit 43 calculates the engine speed calculated based on the detection signal from the crank angle sensor 40, and the driving torque of the engine 10 calculated from the fuel injection amount set by the fuel injection amount setting unit 41. Based on the above, it is determined whether or not the engine 10 is in a predetermined operation state, that is, in the EGR operation region as shown in the map of FIG. 4 in the present embodiment, and the determination result is obtained as the required swirl ratio deriving unit 44 and the actual swirl ratio. Output to the deriving unit 45 and the lowest swirl ratio deriving unit 52, respectively.

  The required swirl ratio deriving unit 44 in the present embodiment has a map as shown in FIG. 5 in which the engine speed, the accelerator opening, and the required swirl ratio are associated with each other, and is based on a detection signal from the crank angle sensor 40. The required swirl ratio corresponding to the calculated engine speed and the accelerator opening detected by the accelerator opening sensor 34 is read from the map of FIG. 5 and is output to the opening / closing timing setting unit 46.

  The actual swirl ratio deriving unit 45 in the present embodiment has a map as shown in FIG. 6 in which the engine speed, the accelerator opening, and the actual swirl ratio are associated with each other, and based on the detection signal from the crank angle sensor 40. The actual swirl ratio actually formed in the combustion chamber 12 is read from the map shown in FIG. 6 from the calculated engine speed and the detection signal from the accelerator opening sensor 34, and this is output to the opening / closing timing setting unit 46. To do.

  The opening / closing timing setting unit 46 derives the minimum swirl ratio when the actual swirl ratio derived by the actual swirl ratio deriving unit 45 is determined when the driving state determination unit 43 determines that the vehicle is not in the predetermined driving state, that is, the EGR driving range. The opening / closing timing of the intake control valve 30 is set so as to be equal to the minimum swirl ratio derived by the section 52, and this is output to the opening / closing timing correction section 49.

  Here, FIG. 8 shows the relationship between the lift amount of the intake valve 25 at the helical intake port 22H, the corresponding air flow rate and the swirl formed in the combustion chamber 12, and a similar relationship at the tangential intake port 22T. As shown in FIG. In the figure, the air flow rate indicated by a solid line increases as the intake valve 25 opens, and tends to be constant over a certain degree of opening. On the other hand, the swirl ratio indicated by the broken line is greatly different between the helical intake port 22H and the tangential intake port 22T. In the helical intake port 22H, the swirl ratio is in the initial stage of opening of the intake valve 25 and thereafter twice. It can be understood that the swirl ratio suddenly increases in the middle of the opening of the intake valve 25 at the tangential intake port 22T. Therefore, when a large swirl ratio is taken into account with the intake air amount at the helical intake port 22H, the opening period of the intake control valve 30 is set to, for example, the region ZH in FIG. A stronger swirl can be formed. However, in the tangential intake port 22T, in order to obtain a large swirl ratio, it is understood that the valve opening period of the intake control valve 30 may be set in a region where the lift amount of the intake valve 25 is large. In other words, when the valve opening period of the intake control valve 30 is set in the region ZT in FIG. 9, the swirl ratio can be kept small while ensuring the intake amount.

  Information on the intake air amount filled in the intake passage 14 between the intake valve 25 and the intake control valve 30 in the closed state, which is derived by the initial intake air amount deriving unit 47, is output to the opening / closing timing correction unit 49. The Similarly, the determination result in the open / close count determination unit 48 is also output to the open / close timing correction unit 49. The information from the initial intake air amount deriving unit 47 brings about a result that the actual swirl ratio becomes larger.

  The required air amount deriving unit 51 in the present embodiment has a map (not shown) related to the fuel injection amount set in advance according to the engine speed, the accelerator opening, the vehicle speed, etc., and the vehicle is in the EGR operation region. In some cases, the minimum amount of air required to completely burn the fuel injection amount set by the fuel injection amount setting unit 41 is read from a map (not shown).

  The minimum swirl ratio deriving unit 52 has a map as shown in FIG. 7 in which the engine speed, the fuel equivalent ratio (reciprocal of the air-fuel ratio), and the minimum swirl ratio are associated with each other. FIG. 7 shows the minimum swirl ratio corresponding to the engine speed calculated based on the fuel injection amount set by the fuel injection amount setting unit 41 and the fuel equivalent ratio calculated from the detection signal from the intake pressure sensor 36. From the map, and outputs this to the opening / closing timing setting unit 46.

  The control device 21 performs intake air via the actuator 29 so that the opening / closing timing set by the opening / closing timing setting unit 46 or the opening / closing timing corrected by the opening / closing timing correction unit 49 according to the driving state of the vehicle. The opening and closing of the control valve 30 is controlled. However, the closing timing for opening and closing the intake control valve 30 is basically set to be the same as or slightly later than the closing timing of the intake valve 25. Further, when the engine 10 is in a predetermined operating state, the control device 21 is configured so that the air amount derived by the actual air amount deriving unit 50 becomes the required air amount derived by the required air amount deriving unit 51. The amount of air flowing into the combustion chamber 12 is controlled. In the present embodiment, when the vehicle is in an EGR operation state, the control device 21 communicates with the intake passage 14 between the intake valve 25 and the intake control valve 30 to guide part of the exhaust gas into the intake passage 14. The amount of air flowing into the combustion chamber 12 is controlled by controlling the opening and closing of the EGR control valve 20 provided at 18. When a throttle valve is provided in the intake passage 14 upstream of the intake control valve 30, the actual air amount is adjusted by adjusting the opening of the throttle valve instead of the EGR control valve 20 described above. It is also possible.

  The procedure of the intake control according to the present invention will be described with reference to the flowchart shown in FIG. 10. First, in step S11, it is determined whether or not the vehicle is in an acceleration state. Here, the vehicle is not in an acceleration state. If it is determined that the intake air flow is not necessary, the control flow is terminated.

  If it is determined in step S11 that the vehicle is in an accelerating state, the actual swirl ratio and actual air amount at this time are derived in step S12, and in step S13, the intake control valve for one cylinder is derived. It is determined whether or not the opening / closing control 30 is the second or later. Since it is not so at the beginning, it transfers to the step of S14 and it is determined whether a vehicle exists in an EGR driving | running | working area | region. Further, when it is determined in step S13 that the opening / closing control of the intake control valve 30 is performed for the second or later time for one cylinder, the process proceeds to step S15 to calculate the initial intake air amount, and then to step S14. Transition.

  If it is determined in step S14 that the vehicle is in the EGR driving range, the process proceeds to step S16 to derive a required swirl ratio. In step S17, whether the required swirl ratio is the same as the actual swirl ratio. Determine whether or not.

  If it is determined in step S17 that the required swirl ratio is the same as the actual swirl ratio, the flow proceeds to step S18 to derive the required air amount, and is this required air amount the same as the actual air amount? It is determined whether or not in step S19. Here, when it is determined that the required air amount is the same as the actual air amount, there is no need to perform further intake air control, so this control flow is terminated.

  If it is determined in step S19 that the required air amount is not the same as the actual air amount, the process proceeds to step S20 to open / close the EGR control valve 20 so that the actual air amount becomes the same as the required air amount. And the amount of exhaust gas introduced into the intake passage 14 is changed.

  On the other hand, if it is determined in step S14 that the vehicle is not in the EGR operation region, the process proceeds to step S21 to derive a minimum swirl ratio, and whether or not this is the same as the actual swirl ratio is determined in step S22. judge. Here, when it is determined that the actual swirl ratio and the minimum swirl ratio are the same, it is not necessary to perform further intake control, and thus this control flow is terminated.

  If it is determined in step S22 that the actual swirl ratio is not the same as the minimum swirl ratio, the intake control valve is adjusted according to the lift amount of the intake valve 25 so that the actual swirl ratio becomes the same as the minimum swirl ratio. After the opening / closing timing of 30 is set in the step of S23, the process proceeds to the step of S24, and it is determined again whether or not the opening / closing control of the intake control valve 30 for the one cylinder is the second or later. Since this is not the case at first, the routine proceeds to step S25, and the intake control valve 30 is opened and closed at the opening / closing timing set in step S23. Thereby, a large amount of intake air can be introduced into the combustion chamber 12 while ensuring a minimum swirl according to the acceleration of the vehicle.

  On the other hand, if it is determined in step S24 that the opening / closing control of the intake control valve 30 for the one cylinder is the second or later, the process proceeds to step S26 and the intake valve 25 derived in step S19 is changed. In consideration of the initial intake air amount filled in the intake passage 14 between the intake control valve 30 and the opening / closing timing is corrected, the process proceeds to step S25, and the opening corrected in step S26 is performed. The intake control valve 30 is opened and closed at the valve timing. As a result, the actual swirl ratio can be detected more accurately, and the control reliability during acceleration of the vehicle can be improved.

  Further, when it is determined in step S17 that the actual swirl ratio is not the same as the required swirl ratio, the intake control valve is adjusted according to the lift amount of the intake valve 25 so that the actual swirl ratio becomes the required swirl ratio. The opening / closing timing of 30 is set in step S27, and the process proceeds to step S24 to determine again whether or not the opening / closing control of the intake control valve 30 is performed for the second or later time for one cylinder. Since this is not the case at first, the routine proceeds to step S25, and the intake control valve 30 is opened and closed at the opening / closing timing set in step S27. Thereby, a large amount of intake air can be introduced into the combustion chamber 12 while ensuring a swirl according to the EGR operation.

  On the other hand, if it is determined in step S24 that the opening / closing control of the intake control valve 30 for the one cylinder is the second or later, the process proceeds to step S26 and the intake valve 25 derived in step S19 is changed. In consideration of the initial intake air amount filled in the intake passage 14 with the intake control valve 30, the opening / closing timing set in the step S27 is corrected, and then the process proceeds to the step S25. The intake control valve 30 is opened and closed at the valve opening timing corrected in the step. As a result, the actual swirl ratio can be detected more accurately, and the control reliability during EGR operation can be improved.

  In the embodiment described above, the case where the predetermined operation state in the present invention is the EGR operation state has been described. However, the fuel post-injection process and the catalyst regeneration process for the catalyst 32 may be cited as the predetermined operation state of the engine 10. it can. That is, if it is determined in step S14 in the flowchart shown in FIG. 10 whether the vehicle is in the post-injection process or the catalyst is being regenerated, and it is determined that the vehicle is in the post-injection process or the catalyst is being regenerated, A required swirl ratio corresponding to each of the post-injection process or the catalyst regeneration process is derived in step S16, and it is determined in step S17 whether or not this is the same as the actual swirl ratio. By setting the opening / closing timing of the intake control valve 30 in step S27 so as to be the same, a required swirl corresponding to the post-injection process or the catalyst regeneration process can be similarly formed in the combustion chamber 12. In this case, the control device 21 includes a post-injection process setting unit 53 and a catalyst regeneration process setting unit 54, and the post-injection process is performed according to the control program set in the post-injection process setting unit 53 and the catalyst regeneration process setting unit 54. The catalyst regeneration process is performed, and information regarding this is output to the operation state determination unit 43.

  Further, in the above-described embodiment, the case where the present invention is applied to the compression ignition engine has been described. However, the direct injection type spark ignition engine using an ignition plug using gasoline, alcohol, LPG (liquefied natural gas) or the like as fuel is described. Is also effective, and the same effect as in the case of the diesel engine described above can be obtained. Further, in the above-described embodiment, the intake control valve 30 is opened and closed to control the swirl ratio. However, the maximum intake amount can be obtained with respect to the combustion chamber 12 when the intake control valve 30 is opened and closed. A swirl control valve that can control the swirl ratio formed in the combustion chamber 12 while being set to the opening / closing timing is incorporated on the upstream side thereof, and the state of the intake air flowing through the intake port 22 is changed to thereby change the swirl control valve. It is also possible to independently control the swirl ratio using.

  FIG. 11 shows an engine system of another embodiment in which such an intake control device according to the present invention is applied to a gasoline engine that is a spark ignition engine, and FIG. 12 shows a control block related to the intake control. Elements having the same function are denoted by the same reference numerals, and redundant description is omitted. That is, the engine 10 according to the present embodiment is of a type in which gasoline, which is fuel, is directly injected into the combustion chamber 12 from the fuel injection valve 11 and ignited by the spark plug 55. However, alcohol or LPG (liquefied natural gas) is used. Etc. can be used as fuel.

  A cylinder head 24 formed with an intake port 22 and an exhaust port 23 respectively facing the combustion chamber 12 includes a valve operating mechanism including an intake valve 25 for opening and closing the intake port 22 and an exhaust valve 26 for opening and closing the exhaust port 23, and a combustion The ignition plug 55 for igniting the air-fuel mixture in the chamber 12 is incorporated, and an ignition coil 56 for generating a spark is mounted on the ignition plug 55. Note that the engine 10 in this embodiment is of a one-valve type, each having an intake valve 25 and an exhaust valve 26.

  A swirl control valve 57 for changing the swirl ratio of the intake air flowing into the combustion chamber 12 from the intake port 22 is provided at the upstream end of the intake port 22, that is, the downstream end of the intake pipe 17. Is connected to a swirl actuator 58 for driving the vehicle based on a command from the control device 21 in a pattern set in advance according to the driving situation of the vehicle.

  In addition, a throttle valve 60 whose opening degree is adjusted by a throttle actuator 59 is incorporated in the portion of the intake pipe 17 between the air cleaner 27 and the surge tank 28 based on the depression amount of the accelerator pedal 33 operated by the driver. It is. In this embodiment, the depression operation of the accelerator pedal 33 and the opening / closing operation of the throttle valve 60 can be separated and electrically controlled. However, the accelerator pedal 33 and the throttle valve 60 are mechanically connected. It may be.

  In the present embodiment, the control device 21 opens the swirl control valve 57 so that the actual swirl ratio derived by the actual swirl ratio deriving unit 45 becomes equal to the required swirl ratio derived by the required swirl ratio deriving unit 44. An opening setting unit 61 that sets the degree of opening, and a valve opening timing setting unit 62 that sets the valve opening timing of the intake control valve 30 so that the maximum intake amount can be obtained for the combustion chamber 12.

  The opening setting unit 61 in the present embodiment has a map as shown in FIG. 13 in which the lift amount of the intake valve 25 is associated with the swirl formed in the combustion chamber 12, and this map is shown in FIG. A state in which the control valve 57 is opened is indicated by a solid line, and a state in which the swirl control valve 57 is closed is indicated by a broken line. The open state of the swirl control valve 57 is controlled via the swirl actuator 58 so as to obtain a desired swirl.

  In the above-described embodiment, the case where the present invention is applied to a direct-injection type gasoline engine has been described. However, the present invention is also effective for a compression ignition engine such as a diesel engine that does not use a spark plug 55, and is similar to the case of a gasoline engine. Effects can be obtained.

It is a conceptual diagram of the engine system in one Embodiment which applied this invention to the diesel engine. It is a conceptual diagram of the part of the intake port in the embodiment shown in FIG. FIG. 2 is a control block diagram in the embodiment shown in FIG. 1. It is a map showing the relationship between an engine speed, a drive torque, and an EGR driving | operation area | region. It is a contour-line map of the request | requirement swirl ratio linked | related with the engine speed and the throttle opening. It is a contour map of the actual swirl ratio linked | related with the engine speed and the throttle opening. It is a contour map of the lowest swirl ratio linked | related with engine speed and fuel equivalent ratio. 3 is a graph showing a relationship between a valve lift amount, a swirl ratio, and an air flow rate at the helical intake port shown in FIG. 2. It is a graph showing the relationship between the valve lift amount in the tangential intake port shown in FIG. 2, a swirl ratio, and an air flow rate. It is a flowchart showing the intake control procedure in embodiment shown in FIG. It is a conceptual diagram of the engine system in other embodiment which applied this invention to the gasoline engine. FIG. 12 is a control block diagram in the embodiment shown in FIG. 11. It is a graph showing the relationship between the valve lift amount and swirl ratio in the embodiment shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Engine 11 Fuel injection valve 12 Combustion chamber 13 Exhaust passage 14 Intake passage 15 Exhaust gas recirculation (EGR) device 16 Exhaust pipe 17 Intake pipe 18 EGR passage 19 EGR pipe 20 EGR control valve 21 Control apparatus 22, 22H, 22T Intake port 23 Exhaust port 24 Cylinder head 25 Intake valve 26 Exhaust valve 27 Air cleaner 28 Surge tank 29 Actuator 30 Intake control valve 31 Piston 32 Catalyst 33 Accelerator pedal 34 Accelerator opening sensor 35 Vehicle speed sensor 36 Intake pressure sensor 37 Cylinder block 38 Connecting rod 39 Crankshaft 40 Crank Angle Sensor 41 Fuel Injection Amount Setting Unit 42 Injection Timing Setting Unit 43 Operating State Determination Unit 44 Required Swirl Ratio Deriving Unit 45 Actual Swirl Ratio Deriving Unit 46 Opening / Closing Timing Setting Unit 47 Initial Intake Amount Deriving Unit 48 Determination unit 49 Opening / closing timing correction unit 50 Actual air amount deriving unit 51 Required air amount deriving unit 52 Minimum swirl ratio deriving unit 53 Post-injection process setting unit 54 Catalyst regeneration process setting unit 55 Spark plug 56 Ignition coil 57 Swirl control valve 58 Swirl actuator 59 Throttle actuator 60 Throttle valve 61 Opening setting unit 62 Valve opening timing setting unit

Claims (8)

An intake control valve provided in the intake passage and capable of opening and closing the intake passage according to the opening and closing timing of the intake valve;
An operating state detecting means for detecting the operating state of the engine;
An intake control device comprising: control means for controlling opening and closing of the intake control valve based on a detection signal from the operating state detection means, wherein the control means includes:
An operation state determination unit for determining whether the engine is in a predetermined operation state based on a detection signal from the operation state detection unit;
A request swirl ratio deriving unit for deriving a required swirl ratio to be formed in the combustion chamber according to the operation state of the engine when the operation state determining unit determines that the engine is in a predetermined operation state;
An actual swirl ratio deriving unit for deriving an actual swirl ratio that is actually formed in the combustion chamber based on a detection signal from the operating state detection means;
An opening / closing timing setting unit for setting the opening / closing timing of the intake control valve so that the actual swirl ratio derived by the actual swirl ratio deriving unit is equal to the required swirl ratio derived by the required swirl ratio deriving unit; The intake control device is characterized in that the opening and closing of the intake control valve is controlled so as to be the opening / closing timing set by the opening / closing timing setting unit. An intake pressure sensor for detecting intake pressure in the intake passage,
The control means derives an intake air amount deriving unit for deriving an intake air amount filled in an intake passage between the intake valve and the intake control valve that are in a closed state based on a detection signal from the intake pressure sensor. When,
An opening / closing frequency determination unit that determines whether or not the setting of the opening / closing timing of the intake control valve by the opening / closing timing setting unit is the second or later time after starting the opening / closing control of the intake control valve;
When it is determined by the opening / closing frequency determination unit that the setting of the opening / closing timing of the intake control valve is the second or later time after starting the opening / closing control of the intake control valve, it is set by the opening / closing timing setting unit. The intake control device according to claim 1, further comprising: an open / close timing correction unit that corrects the open / close timing of the intake control valve in accordance with the intake air amount derived by the initial intake air amount deriving unit. An actual air amount deriving means for deriving an actual air amount introduced into the combustion chamber;
The control means further includes a required air amount deriving unit for deriving a minimum air amount to be introduced into the combustion chamber according to a predetermined operation state,
When the engine is in a predetermined operating state, the control means is arranged in the combustion chamber so that the air amount derived by the actual air amount deriving unit becomes the required air amount derived by the required air amount deriving unit. The intake air control device according to claim 1 or 2, wherein the intake air amount is controlled.   The predetermined operation state is an EGR operation state, and the control means is provided in an EGR passage that communicates with an intake passage between the intake control valve and the intake valve and guides a part of the exhaust gas into the intake passage. The intake air control apparatus according to claim 3, wherein the amount of air flowing into the combustion chamber is controlled by controlling opening and closing of the EGR control valve. The control unit further includes a minimum swirl ratio deriving unit that derives a minimum swirl ratio at which the air-fuel mixture can normally burn in the combustion chamber based on a detection signal from the operating state detection unit,
The opening / closing timing setting unit determines that the actual swirl ratio derived by the actual swirl ratio deriving unit is the minimum swirl ratio deriving unit when the operation state determining unit determines that the engine is not in a predetermined operation state. The intake control device according to any one of claims 1 to 4, wherein the opening / closing timing of the intake control valve is set so as to be equal to the lowest swirl ratio derived in this manner. A plurality of intake valves for opening and closing a plurality of intake ports respectively communicating with one combustion chamber, and a ratio of intake air flowing through the plurality of intake ports can be changed to change a swirl ratio of intake air formed in the combustion chamber A swirl control valve, an intake control valve that is provided in the intake passage upstream of the swirl control valve and that can open and close the intake passage according to the opening and closing timing of the intake valve, and an operating state detection means that detects the operating state of the engine And an intake control device comprising control means for controlling opening and closing of the swirl control valve and the intake control valve based on a detection signal from the operating state detection means, wherein the control means includes:
A required swirl ratio deriving unit for deriving a required swirl ratio to be formed in the combustion chamber based on a detection signal from the operating state detecting means;
An actual swirl ratio deriving unit for deriving a swirl ratio of intake air actually formed in the combustion chamber based on a detection signal from the operating state detecting means;
An opening setting unit for setting the opening of the swirl control valve so that the actual swirl ratio derived by the actual swirl ratio deriving unit is equal to the required swirl ratio derived by the requested swirl ratio deriving unit; ,
And a valve opening timing setting section for setting a valve opening timing of the intake control valve so as to obtain a maximum intake amount. An intake control method for an engine provided with an intake control valve capable of opening and closing an intake passage according to the opening and closing timing of the intake valve,
Detecting the operating state of the engine;
Determining whether the detected engine operating state is in a predetermined operating state;
Deriving a required swirl ratio to be formed in the combustion chamber according to the operating state of the engine when it is determined that the engine is in a predetermined operating state;
Deriving an actual swirl ratio that is actually formed in the combustion chamber according to the detected operating state of the engine;
Setting the opening / closing timing of the intake control valve so that the derived actual swirl ratio is equal to the derived required swirl ratio;
And a step of controlling the opening and closing of the intake control valve so as to reach a set opening and closing timing. Detecting the intake pressure in the intake passage;
Deriving an intake air amount to be filled in an intake passage between the intake valve and the intake control valve that are in a closed state based on the detected intake pressure;
Determining whether or not the setting of the opening / closing timing of the intake control valve is a second or later time after starting the opening / closing control of the intake control valve;
When it is determined that the setting of the opening / closing timing of the intake control valve is the second or later time after starting the opening / closing control of the intake control valve, the set opening / closing timing of the intake control valve is set to the derived intake air amount. The intake control method according to claim 7, further comprising a step of correcting in response.

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