JP2006170070A - Engine intake air control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce operation frequency of a TGV opening sensor and a TGV driving actuator, relatively substantialize improvement in durability, and obtain good drivability by reducing opening/closing frequency of the TGV in a region where idle control is continuously performed such as while traveling on a congested road or in parking. <P>SOLUTION: An auxiliary passage 13 and a main passage 14 are formed downstream of a throttle valve 9. The TGV 15 for opening/closing the main passage 14 is arranged upstream of both passages 13 and 14. An injector 16 is arranged upstream of the auxiliary passage 13. During idle operation after traveling at the vehicle speed S exceeding a set speed So, control to close the TGV 15 is permitted (S15). During idle operation from a traveling state where the vehicle speed S does not exceed the set speed So, control to close the TGV 15 is prohibited (S12). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an intake control device for an engine that reduces the operation frequency of an intake flow control valve and improves durability.

  Conventionally, an intake flow control valve is provided immediately upstream of the intake port, and by closing a part of the intake passage by this intake flow control valve, swirl flow into the combustion chamber is achieved by inertial supercharging of intake air flowing into the combustion chamber. Various intake devices that improve the combustion efficiency by generating a vortex flow such as a tumble flow or the like have been proposed.

  In an engine equipped with this type of intake device, when the engine operating state is low load operation including idle operation, closing the intake flow control valve increases the amount of intake air that is filled in the combustion chamber due to the inertia boost effect. be able to. However, when a large amount of intake air is required, such as high-load operation or high-speed operation, the charging efficiency can be increased by reducing the intake resistance when the intake flow control valve is opened.

  For example, in Patent Document 1 (Japanese Patent Application Laid-Open No. Hei 6-193456), a shutter valve is provided upstream of each of two intake ports provided in each cylinder, and the shutter valve on the primary side of the both shutter valves is provided. A notch is formed. During cold idle operation and low load, both shutter valves are fully closed and a notch formed in the primary side shutter valve is disposed on the lower side. Then, the intake air passes through a notch opened on the lower side of the shutter valve on the primary side, and a swirl is generated at that time. On the other hand, during warm idle operation and low load, a technique is disclosed in which a notch formed in the shutter valve on the primary side is opened upward and a tumble flow is generated in the intake air passing through the notch.

According to the technique disclosed in this document, in the cold state, a swirl flow causes a rich air-fuel mixture to be distributed around the periphery of the combustion chamber to cause afterburning with unburned gas. By activating the catalyst, the amount of HC emission can be reduced, and in the warm state, the turbulence of the air-fuel mixture can be increased by the tumble flow to ensure combustion stability.
JP-A-6-193456

  By the way, the intake flow control valve is controlled to open and close according to the operating state of the engine. If the intake flow control valve is frequently opened and closed, for example, the opening of the intake flow control valve is changed to a contact type opening sensor such as a potentiometer. Or when the number of endurance operations, which is the number of guaranteed operations of the motor that drives the intake flow control valve, is specified, for example, when the intake flow control valve is closed during idle operation As a result, the opening / closing operation frequency of the intake flow control valve increases, and the durability of the opening sensor and the motor decreases.

  On the other hand, control that always closes the intake flow control valve during idling operation, and idle control is performed intermittently during traffic jams and when entering the garage, so that the intake flow control valve opens and closes frequently. become. Since the combustion mode changes during the transition when the intake flow control valve opens and closes, if idle control is intermittently performed and the open / close operation frequency of the intake flow control valve increases, drivability is hindered and the driver is There is a problem that gives a sense of incongruity.

  In the technique disclosed in the above-described document, there is no distinction between idle operation and low load operation. For example, when normally closed control is performed during idle operation, idle operation may be performed during traffic jams or when entering a garage. Since it is performed intermittently, the shutter valve opens and closes frequently.

  As a result, the opening / closing operation frequency of the intake flow control valve is increased, and not only the durability is deteriorated, but also the drivability is deteriorated because the combustion mode changes in a transient time when the intake flow control valve is opened / closed. .

  In view of the above circumstances, the present invention can reduce the opening / closing operation frequency of the intake flow control valve even in an area where idle control is intermittently performed such as traffic congestion and garage entry, and is relatively durable. An object of the present invention is to provide an intake control device for an engine that can achieve improvement and obtain good drivability.

  In order to achieve the above object, the present invention provides an engine intake control apparatus in which an injector is disposed in an intake passage downstream of a throttle valve and an intake flow control valve is disposed between the throttle valve and the injector. Intake flow control valve control means for controlling the opening and closing of the intake flow control valve according to at least one experience state with respect to the intake air amount is provided.

  According to the present invention, since the opening / closing of the intake flow control valve is controlled based on at least one of the vehicle speed and the intake air amount, it is a region where idle control such as traffic congestion and garage entry is intermittently performed. However, it is possible to reduce the frequency of the intake flow control valve without frequently opening and closing it, to achieve a relatively improved durability, and to obtain good drivability.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an overall configuration diagram of the engine.

  Reference numeral 1 in FIG. 1 denotes an engine body, and a cylinder head 3 is provided on the upper portion of the engine body 1, and an intake port 4 communicating with a combustion chamber 1 a formed in the engine body 1 is connected to the cylinder head 3. An exhaust port 5 is provided. In addition, an intake valve 2a and an exhaust valve 2b that open and close the ports 4 and 5 are disposed in the ports 4 and 5, respectively.

  An intake passage 6 communicates with the intake port 4 via an intake manifold 7, and an air cleaner 8 is disposed upstream of the intake passage 6. A throttle valve 9 is disposed in the intake passage 6. On the other hand, a catalyst 11 is interposed in the middle of the exhaust passage 10 communicating with the exhaust port 5.

  The intake manifold 7 is provided with a partition wall 12 that vertically separates the interior thereof. The partition wall 12 divides the interior of the intake manifold 7 into a sub-passage 13 having a small passage area and a main passage 14 having a large passage area.

  Further, a tumble generation valve (TGV) 15 as an intake flow control valve capable of opening and closing the main passage 14 is disposed at the upstream end of the main passage 14. Further, an injector 16 is disposed upstream of the sub-passage 13 with the injection port directed toward the intake port 4.

  The engine body 1 is provided with a water temperature sensor 17 for detecting the cooling water temperature, which is representative of the engine temperature, and an intake air amount sensor 18 for detecting the intake air amount is provided immediately downstream of the air cleaner 8 in the intake passage 6. A throttle opening sensor 19 that detects the throttle opening is connected to the valve 9, and a TGV opening sensor 15 a that detects the operating state of the TGV 15 is connected to the TGV 15.

  The TGV opening degree sensor 15a is a normal contact type opening degree sensor using a potentiometer, for example, and detects the opening degree ratio Vtv of the TGV 15 based on the voltage change output from the TGV opening degree sensor 15a. That is, in the electronic control unit (ECU) 30 described later, when the output of the TGV opening sensor 15a is TGV opening rate Vtv = 0% when the TGV 15 is fully opened and Vtv = 100% when it is fully closed, the TGV opening rate Vtv When 0%, it is determined that the valve is fully open, when the TGV opening rate Vtv = 100%, it is determined that the valve is fully closed, and when 0% <TGV opening <100%, it is determined that there is a transition. In addition, you may comprise this TGV opening degree sensor 15a with a double switch, for example. In this case, one switch is set to be turned on when the TGV is fully closed, and the other switch is turned on when the TGV is fully opened. As a result, when one of the switches is turned on, it is detected whether the switch is fully closed or fully open.

  Reference numeral 30 denotes an electronic control unit (ECU). An input side of the ECU 30 includes a water temperature sensor 17 for detecting the cooling water temperature, an intake air amount sensor 18 for detecting an intake air mass flow rate downstream of the air cleaner 8, and a throttle valve 9. The throttle opening degree sensor 19 for detecting the throttle opening degree Vth, the engine speed sensor 21 for detecting the engine speed from the rotation speed of the crankshaft, and the accelerator opening degree Va from the amount of depression of an accelerator pedal (not shown) are detected. Sensors and switches for detecting the engine operating state such as the accelerator opening sensor 22 are connected. Various output actuators such as an injector driving actuator (not shown) for driving the injector 16 and a TGV driving actuator 15 b for driving the TGV 15 are connected to the output side of the ECU 30. In this embodiment, a driving motor that reciprocates in two directions (fully opened and fully closed) is used as the TGV driving actuator 15b. However, by selectively supplying the intake pipe negative pressure downstream of the throttle valve 9, A diaphragm actuator that opens and closes may be used.

  The ECU 30 executes fuel injection control, TGV control, and the like based on signals from sensors and switches that detect the engine operating state.

  In the TGV control, when the engine operation state is low / medium load operation, a close signal is output to the TGV drive actuator 15b. Then, the TGV 15 is closed to close the main passage 14. As a result, the intake air passes through the side of the auxiliary passage 13 with the increased flow velocity, and generates a tumble flow in the combustion chamber 1a. In the combustion chamber 1a, the gas flow is enhanced by the tumble flow, the combustion speed is accelerated, and high charging efficiency can be obtained by inertia supercharging.

  On the other hand, when the engine operation state is high rotation or high load operation, an open signal is output to the TGV driving actuator 15b. Then, the TGV 15 is opened, and the intake air passes through both the main passage 14 and the sub-passage 13 and flows to the combustion chamber 1a. When the TGV 15 is opened, the intake resistance by the TGV 15 is reduced and the generation of the tumble flow is suppressed, so the amount of intake air flowing into the combustion chamber 1a is increased and the engine output is improved.

  Thus, when the main passage 14 is opened and closed by the TGV 15, the passage area of the intake manifold 7 changes, and the air flow rate and the inflow route into the combustion chamber 1a change. As a result, the state of the intake air flowing into the combustion chamber 1a changes and the combustion mode changes.

  By the way, when a contact-type opening sensor is employed as the TGV opening sensor 15a, the contact-type opening sensor defines the number of durable operations for guaranteeing operation. Similarly, the TGV driving actuator 15b also defines the number of durable operations for guaranteeing the operation. Therefore, the durability of the TGV opening sensor 15a and the TGV driving actuator 15b can be improved by reducing the operating frequency of the TGV 15.

  Further, when the main passage 14 is opened and closed by the TGV 15, the state of the intake air flowing into the combustion chamber 1a changes and the combustion mode changes. Therefore, if the opening and closing of the TGV 15 is frequently repeated, drivability is hindered. .

  In the TGV control executed by the ECU 30, the opening / closing operation frequency of the TGV 15 during idle operation is reduced, so that the durability of the TGV opening sensor 15a and the TGV driving actuator 15b is relatively improved, and the combustion mode We try to improve drivability by reducing changes.

  Hereinafter, the opening degree control of the TGV 15 executed by the ECU 30 will be described based on the flowcharts shown in FIGS.

  When an ignition switch (not shown) is turned on, first, a start time TGV control routine shown in FIG. 3 is executed. In this routine, a close signal is output to the TGV driving actuator 15b in step S1. Then, the TGV driving actuator 15b drives the TGV 15 and closes the main passage 14 (state shown in FIGS. 1 and 2).

  Subsequently, it progresses to step S2 and it is investigated whether the engine started. Whether or not the engine has started is determined based on whether or not the engine speed Ne detected by the engine speed sensor 21 has reached a preset spontaneous speed (for example, 600 rpm), or after the starter switch is turned on, Judgment is made based on whether or not it is turned off.

  If the engine has not yet been started, the system waits until the engine starts. On the other hand, when it is determined that the engine has started, the process proceeds to step S3. When the engine is started, the intake air introduced into the intake passage 6 from the air cleaner 8 side passes through the sub passage 13 side, is supplied to the combustion chamber 1a in a state where the flow velocity is increased, and generates a tumble flow in the combustion chamber 1a. In the combustion chamber 1a, the gas flow is strengthened by the tumble flow and the combustion speed is promoted, so that good startability can be obtained.

  In step S3, the timer is turned on. Thereafter, in step S4, the process waits until the elapsed time T counted by the timer reaches the TGV closing time set value Ts. When T> Ts is reached, the process proceeds to step S5. In step S5, the elapsed time T counted by the timer is cleared (T ← 0). After that, in step S6, the start time TGV closing control end flag FS is set (FS ← 1), and the routine is ended. Note that the initial value of the start time TGV closing control end flag FS is 0, and once set after the engine is started, the state of FS = 1 is maintained until the engine is stopped. The value of the start time TGV close control end flag FS is read in an idle time TGV close control limit routine of FIG.

  On the other hand, when the engine is started, a TGV closing permission determination routine shown in FIG. 4 is executed every set calculation cycle. In this routine, first, in step S11, it is checked whether or not the TGV 15 is in a transition state in which it shifts from the closed state to the open state. Whether or not the operation of the TGV 15 is in a transitional state in which the operation shifts from the closed state to the open state is determined based on the output of the TGV opening sensor 15a. That is, when the TGV opening rate Vtv detected by the TGV opening sensor 15a is 0% when fully opened and 100% when fully closed, the TGV opening rate Vtv detected by the output value from the TGV opening sensor 15a is 100%. When changing from 0% to 0%, it is determined that the transition is from the closed to the open direction.

  If it is determined that the TGV 15 is in a transitional state in which the TGV 15 changes from the closed direction to the open direction, the process proceeds to step S12, the TGV close control permission flag FTGV is cleared (FTGV ← 0: TGV close control prohibited), and the routine is exited.

  On the other hand, if the TGV 15 is in either the open state or the closed state, the process proceeds to step S13 to check whether the TGV 15 is in the open state. Whether or not the TGV 15 is in an open state is determined based on, for example, the TGV opening rate Vtv calculated from the output value of the TGV opening sensor 15a. When the TGV opening rate Vtv = 0%, it is determined that the TGV 15 is fully open. When it is 100%, it is determined to be fully closed.

  When it is determined that the TGV 15 is fully open and the process proceeds to step S14, it is checked whether the vehicle speed S is equal to or higher than a set speed So (for example, about 20 to 30 Km / h). If the speed is equal to or higher than the set speed So (S ≧ So), Proceeding to step S15, the TGV closing control permission flag FTGV is set (FTGV ← 1: TGV closing control permission), and the routine is exited.

  In the TGV closing permission determination routine according to the present embodiment, when the vehicle speed S experiences the set speed So or higher when the TGV 15 is in the fully opened state, the TGV closing control permission flag FTGV is set to permit the TGV closing control. However, instead of the vehicle speed S, the intake air amount Q is set as a permission condition, and when the intake air amount Q has experienced a set air amount Qo or more, the TGV close control permission flag FTGV is set to permit the TGV close control. Anyway. Alternatively, the TGV closing control may be permitted when both the vehicle speed S and the intake air amount Q are equal to or higher than the set values So and Qo. In this case, it may be determined whether to permit the TGV closing control based on the intake pipe pressure downstream of the throttle valve 9 instead of the intake air amount Q.

  On the other hand, after the engine is started, the idle time TGV closing control restriction routine shown in FIG. 5 is also executed at every predetermined calculation cycle. In this routine, first, in step S21, the value of the start time TGV close control end flag FS is referred to, and it is checked whether or not FS = 1, that is, whether or not the close control of the TGV 15 is ended at the time of engine start. If the closing control of the TGV15 with FS = 0 has not ended, the routine jumps to step S26, the idle TGV closing control permission flag FTGVid is cleared (FTGVid ← 0: closing control prohibited during idling), and the routine is exited. Further, when the closing control of the TGV 15 with FS = 1 is finished, the process proceeds to step S22.

  When proceeding to step S22, it is checked whether or not the warm-up operation has been completed based on the coolant temperature detected by the water temperature sensor 17. If the warm-up operation has not been completed, the process jumps to step S26 to determine that the warm-up has been completed. At this time, the process may proceed to step S22.

  In step S22, the accelerator opening degree Va detected by the accelerator opening sensor 22 is compared with the set opening degree Vao. The accelerator opening rate Va is set to 0% when the accelerator pedal is released and 100% when the pedal is fully depressed. The set opening rate Vao is set to the accelerator opening rate Va when there is traffic jam or garage entry. It is set to an upper limit value (for example, Vao = about 15-20%) when the pedal is in a low opening rate region operated with a slight depression (Va≈about 1-15%).

  When Va> Vao, it is determined that the accelerator opening rate Va is out of the low opening rate region, jumping to step S26, and clearing the idle TGV closing control permission flag FTGVid (FTGVid ← 0). ) Exit the routine. On the other hand, when the accelerator opening degree Va of Va ≦ Vao is in the low opening degree region, the process proceeds to step S23.

  In step S23, the engine speed Ne is compared with the set speed Neo. The set rotational speed Neo is set to an upper limit value when the engine rotational speed Ne is in the low rotational speed region. When Ne> Neo, it is determined that the engine speed Ne is out of the low speed range, the process jumps to step S26, and the idle time TGV closing control permission flag FTGVid is cleared (FTGVid ← 0). Exit the routine. On the other hand, when it is determined that the engine speed Ne of Ne ≦ Neo is in the low speed region, the process proceeds to step S24.

  In step S24, the intake air amount Q is compared with the set air amount Qa. The set air amount Qa is set to an upper limit value when the intake air amount Q is in the air amount region during low load operation. When Q> Qa, it is determined that the intake air amount Q is out of the air amount region during low load operation, jumps to step S26, and clears the idle TGV close control permission flag FTGVid (FTGVid). ← 0), exit the routine. On the other hand, when it is determined that the intake air amount Q of Q ≦ Qa is in the air amount region during the low load operation, the process proceeds to step S25.

  Then, in steps S22 to S24, it is determined that Va ≦ Vao, Ne ≦ Neo, and Q ≦ Qa. When the process proceeds to step S25, the value of the TGV closing control permission flag FTGV is referred to. The TGV closing control permission flag FTGV is cleared in step S12 of the TGV closing permission determination routine shown in FIG. 4 and set in step S15.

  That is, it is cleared when the opening rate Vtv of the TGV 15 is in a transitional state changing from the closed direction to the open direction (FTGV ← 0), the TGV opening rate Vtv is fully open, and the vehicle speed S is equal to or higher than the set speed. Set when experiencing (FTGV ← 0). When the TGV opening rate Vtv indicates fully closed or the vehicle speed S is less than the set speed So, the value of the previously set TGV close control permission flag FTGV is maintained.

  Then, when FTGV = 1, it is determined that TGV closing control is permitted, the process proceeds to step S27, an idle time TGV closing control permission flag FTGVid is set (FTGVid ← 1: idling time closing control permission), and routine Exit. If FTGV = 0, it is determined that TGV closing control is prohibited, and the process branches to step S26, the idle time TGV closing control permission flag FTGVid is cleared (FTGVid ← 0), and the routine is exited.

  The value of the idle TGV closing control permission flag FTGVid is read in the idle TGV control routine shown in FIG. This routine is executed every set calculation cycle. First, in step S31, the throttle opening rate Vth of the throttle valve 9 detected by the throttle opening sensor 19 is read. In step S32, the engine opening rate Vth is determined based on the throttle opening rate Vth. It is checked whether or not the operation state is an idle operation state. If the operation state is an idle operation state, the process proceeds to step S33.

  Further, when in the non-idle operation state, the process branches to step S34, executes the TGV normal control process, and exits the routine. The TGV normal control process is a region excluding a high load or high rotation region, and when parameters indicating the engine operating state such as the engine speed Ne, the engine load, and the throttle opening rate Vth are equal to or less than a set value, the TGV drive actuator 15b Is output to close the TGV 15. On the other hand, when these parameters indicating the engine operating state are equal to or greater than the set value, an opening signal is output to the TGV driving actuator 15b to open the TGV 15. When the TGV 15 is closed, the intake air passes through the sub-passage 13 side, is supplied to the combustion chamber 1a in a state where the flow velocity is increased, and a tumble flow is generated in the combustion chamber 1a.

  If it is determined that the engine is in the idle operation state and the process proceeds to step S33, the value of the idle TGV closing control permission flag FTGVid is referred to. When the idle TGV closing control with FTGVid = 1 is permitted, the process proceeds to step S35, and a closing signal is output to the TGV driving actuator 15b to exit the routine. On the other hand, when the idle TGV closing control of FTGVid = 0 is prohibited, the process branches to step S36, and an open signal is output to the TGV driving actuator 15b to exit the routine.

  As a result, even in the idling state, when the idle time TGV closing control permission flag FTGVid is cleared (FTGVid = 0), the TGV 15 does not close, so that, for example, the accelerator pedal is slightly depressed and the accelerator pedal is released. In an operation region such as a traffic jam or a garage where the vehicle travels repeatedly, the opening and closing of the TGV 15 is not frequently repeated, and therefore the combustion mode does not change and good drivability can be obtained. Further, since the frequency of opening and closing the TGV 15 is reduced, the durability of the TGV opening sensor 15a and the TGV driving actuator 15b can be improved.

  Next, an example of TGV control executed by the ECU 30 will be described using the time chart shown in FIG. When the ignition switch is turned on, the TGV 15 is closed. Thereafter, when the engine is started, the timer starts measuring the elapsed time T (t0), and the valve closing state of the TGV 15 is maintained until the elapsed time T reaches the TGV closing time set value Ts (t1). Thereafter, the opening / closing control of the TGV 15 is performed based on parameters indicating the engine operation state such as the coolant temperature, the engine speed Ne, the engine load, the accelerator opening rate Va, and the throttle opening rate Vth. In the figure, the elapsed times t1 to t2 indicate the idle operation state in which the accelerator pedal is released, and the TGV 15 is maintained in the closed state.

  Thereafter, when the vehicle is started with the accelerator pedal depressed, the TGV 15 is opened when the operating conditions such as the accelerator opening rate Va at that time become equal to or higher than a set value (t2). When the vehicle speed S exceeds the set speed So (t3), the TGV closing control permission flag FTGV is set, and the TGV closing control is permitted.

  Thereafter, when the vehicle decelerates and stops, the operating conditions such as the accelerator opening rate Va at that time become equal to or less than the set value, and the TGV 15 is closed (t4). On the other hand, since the TGV 15 shifts from the open state to the closed state at this time, the value of the TGV close control permission flag FTGV is kept at FTGV = 1.

  Then, when the accelerator pedal is depressed and the vehicle restarts, the TGV 15 opens when the operating conditions such as the accelerator opening rate Va at that time become equal to or higher than a set value (t5). At the same time, since the TGV 15 has changed from closed to open, the TGV close control permission flag FTGV is cleared and the TGV close control is prohibited.

  When the vehicle speed S after the start shifts to the idle operation from the state below the set speed So as shown in the elapsed times t5 to t6, that is, for example, a state where the accelerator pedal is stepped on, for example, in a traffic jam or in a garage, In the driving region in which the vehicle travels repeatedly in the open state, the vehicle speed S shifts to idle operation in a state where the vehicle speed S does not exceed the set speed So, so that the close control of the TGV 15 is prohibited. As a result, since the idle TGV closing control permission flag FTGVid is cleared, the TGV 15 is not closed, and the combustion mode does not change in the operation region in which the idle operation is repeated intermittently, and good drivability can be obtained. it can.

Overall configuration diagram of the engine 1 is an enlarged view of the main part of FIG. Flowchart showing start-up TGV control routine Flowchart showing TGV closing permission determination routine Flowchart showing idle time TGV closing control limiting routine Flowchart showing idle time TGV control routine Time chart showing TGV control

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Engine main body 1, 4 ... Intake port, 6 ... Intake passage, 9 ... Throttle valve, 13 ... Sub passage, 14 ... Main passage, 15 ... TGV, 15a ... TGV opening sensor, 15b ... Actuator for TGV drive, 16 DESCRIPTION OF SYMBOLS ... Injector, 19 ... Throttle opening sensor, 21 ... Engine speed sensor, 22 ... Accelerator opening sensor, 30 ... Electronic control unit, FS ... Close control end flag, FTGV ... TGV close control permission flag, FTGVid ... TGV at idling Close control permission flag, Ne ... engine speed, Neo ... set speed, Q ... intake air amount, Qa, Qo ... set air amount, S ... vehicle speed, So ... set speed, Ts ... close time set value, Va ... accelerator Opening rate, Vao ... set opening rate, Vth ... throttle opening rate, Vtv ... TGV opening rate

Agent Patent Attorney Susumu Ito

Claims (3)

In an engine intake control device in which an injector is disposed in an intake passage downstream of a throttle valve, and an intake flow control valve is disposed between the throttle valve and the injector,
An intake air control apparatus for an engine, comprising an intake air flow control valve control means for controlling opening and closing of the intake air flow control valve in accordance with at least one of the vehicle speed and the intake air amount. The intake flow control valve control means includes
2. The engine intake control device according to claim 1, wherein opening and closing of the intake flow control valve is controlled according to at least one of the vehicle speed and the intake air amount when the intake flow control valve is opened. The intake flow control valve control means includes
When at least one of the vehicle speed and the intake air amount when the intake flow control valve is opened exceeds a set value, the closing operation of the intake flow control valve is permitted,
2. The closing operation of the intake flow control valve is prohibited when at least one of the vehicle speed and the intake air amount when the intake flow control valve is opened does not experience a set value or more. 2. An intake control device for an engine according to 2.

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