JPH0658192A - Intake air control device for internal combustion engine - Google Patents

Abstract

PURPOSE:To save the power consumption while worsening or intake air characteristics is prevented from occurring by effecting control of energization to a rotary solenoid actuator, by which an intake air control valve is opened and closed, so that, in an engine where an intake air valve is closed, an energizing amount is decreased. CONSTITUTION:In a four-cylinder engine 1 wherein an intake air valve 9 and an exhaust gas valve 11 are arranged to each cylinder 7, a throttle valve 13 is arranged to an intake air system 1a and an intake air control valve 19 is arranged to each of intake air ports 17 branched from the intake air system 1a. The intake air control valve 19 is held at a neutral position, where an intake air passage is brought into a half-opened state, during non-energization and driven for opening and closing in a direction corresponding to an energizing direction during energization by means of a rotary solenoid (R/S) actuator 21. In this case, in an engine wherein an influence is not exercised on intake air characteristics and an intake air valve 9 is closed, an amount of energization to the R/S actuator 21 is decreased to save a power.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake control device for an internal combustion engine, which controls an intake air amount by opening / closing an intake control valve provided in an intake passage of the internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Unexamined Patent Publication No. 63-6513.
As disclosed in Japanese Patent Publication No. 8, an intake control valve is provided in an intake passage of an internal combustion engine, and opening / closing control of the intake control valve is performed.
There is known an intake control device capable of controlling the intake air amount for each cylinder separately from a throttle valve provided in an internal combustion engine.

Further, in this type of intake control device, the intake passage of the internal combustion engine can be opened and closed by the intake control valve at a desired timing. Therefore, the opening / closing timing of the intake control valve must be controlled according to the rotational speed and load of the internal combustion engine. This prevents backflow of intake air that occurs during the intake stroke in the low speed range of the internal combustion engine to improve torque, or improves fuel efficiency by reducing pumping loss during partial load of the internal combustion engine. Is also proposed.

Further, in the intake control device of this type, as an actuator for opening and closing the intake control valve, the intake control valve is held in a neutral position where the intake passage is half-opened when not energized, and when it is energized, its energizing current and its current direction. It is also proposed to use a 90 ° swing type rotary solenoid actuator (hereinafter, also simply referred to as R / S actuator) that drives the intake control valve from the neutral position to the opening direction or the closing direction of the intake passage in accordance with the above. (Japanese Patent Application No. 3-52
721).

When an R / S actuator that holds the intake control valve in the neutral position when de-energized is used as the actuator that opens and closes the intake control valve as described above, the R / S actuator may malfunction or the like. Even if the R / S actuator cannot be energized, the internal combustion engine can be operated without closing the intake passage, so safety can be ensured, and by switching the energizing direction, Since the opening / closing direction of the intake control valve can be switched, the intake control valve can be driven at high speed from the fully open position to the fully closed position, or from the fully closed position to the fully open position.

[0006]

However, in the case of performing the intake control valve by using the R / S actuator as described above, even if the opening / closing control of the intake control valve is not executed (that is, the intake control valve is fully opened). To hold in position)
However, it is necessary to always energize the R / S actuator. Therefore, when the R / S actuator is used to open and close the intake control valve, there is a problem that the power consumption increases.

The present invention has been made in view of these problems, and in the intake control device for controlling the intake air amount by using the R / S actuator as described above, the R characteristic can be improved without deteriorating the intake characteristic of the internal combustion engine. The purpose is to reduce the power consumption of the / S actuator.

[0008]

The invention according to claim 1 made in order to achieve the above object is, as illustrated in FIG. 1, an intake control valve provided in an intake passage of an internal combustion engine,
When not energized, the intake control valve is held in a neutral position where the intake passage is half-opened, and when energized, a rotary solenoid actuator that opens and closes the intake control valve in a direction corresponding to the energizing direction according to the energizing current, and the internal combustion engine. The intake control valve is opened and closed in synchronization with the opening and closing of an intake valve of the internal combustion engine that is opened and closed in synchronization with the crank angle of the engine, and the opening and closing timing of the intake control valve is set to the operating state of the internal combustion engine. In an intake control device for an internal combustion engine, comprising: an intake control unit that adjusts in accordance with the above, an energization control that controls energization to the rotary solenoid actuator in response to an opening / closing command from the intake control unit to open / close the intake control valve. An energization control means for reducing the amount of energization to the rotary solenoid actuator while the intake valve is closed. It is characterized in that it comprises.

As shown in FIG. 1, the invention described in claim 2 is an internal combustion engine equipped with an intake control valve, a rotary solenoid actuator, and intake control means, as in the case of the invention described in claim 1. In the intake control device, the energization control means for controlling the energization of the rotary solenoid actuator according to an opening / closing command from the intake control means to open / close the intake control valve, in a range in which a required intake characteristic is obtained. It is characterized by further comprising energization control means for energizing the rotary solenoid actuator with an energizing current set to be low.

[0010]

In the intake control device according to the first aspect of the present invention configured as described above, the energization of the rotary solenoid actuator is controlled in accordance with the opening / closing command from the intake control means to operate the intake control valve. The energization control means that opens and closes reduces the amount of power to the rotary solenoid actuator that opens and closes the intake control valve while the intake valve of the internal combustion engine that is driven to open and close in synchronization with the crank angle of the internal combustion engine is closed.

That is, while the intake valve is closed, opening and closing the intake control valve provided in the upstream intake passage does not affect the intake characteristics of the internal combustion engine. While the intake valve is closed, the amount of electricity supplied to the rotary solenoid actuator that opens and closes the intake control valve is reduced.

Therefore, according to the intake control device of the first aspect, the intake characteristic of the internal combustion engine is not deteriorated,
Power consumption of the rotary solenoid actuator can be reduced. Further, in the intake control device according to the second aspect, the energization control means energizes the rotary solenoid actuator with the energization current that is set low within the range in which the required intake characteristic is obtained.

That is, in the device for opening and closing the intake control valve using the rotary solenoid actuator as in the present invention, a general internal combustion engine that does not include the intake control valve unless the intake air amount is controlled by the intake control valve. In order to secure an intake passage similar to the above, the intake control means energizes the rotary solenoid actuator to fully open the intake passage.At this time, for example, when the internal combustion engine is operating under a low load, the internal combustion engine receives a large amount of intake air. In an operating state that does not require air, even if the intake passage is narrowed by moving the intake control valve from the fully open position to the neutral position side, the intake characteristics may not be affected.

Further, when the intake passage is closed to control the intake air amount, the intake control means energizes the rotary solenoid actuator in the direction opposite to the direction in which the intake control valve is opened to fully close the intake control valve. However, even in this case, the intake characteristic may not be affected even if the intake control valve is moved from the fully closed position to the neutral position side depending on the operating state of the internal combustion engine, the structure of the intake control valve, and the like. is there.

Therefore, in the present invention, when the required intake characteristic is obtained even if the intake control valve is moved to the neutral position side, the energization current of the rotary solenoid actuator is set to be low within the range, and the intake control is performed. By moving the valve toward the neutral position, the power consumption of the rotary solenoid actuator is reduced.

Therefore, according to the intake control device of the second aspect, like the intake control device of the first aspect, the power consumption of the rotary solenoid actuator is reduced without deteriorating the intake characteristic of the internal combustion engine. can do.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows the system configuration of an engine equipped with the intake control device of this embodiment. As shown in FIG. 2, the system configuration of the engine is a four-cylinder engine 1, an intake control unit 3 provided in an intake system 1a of the engine 1, and an electronic control unit (hereinafter referred to as ECU) 5 for controlling these. Etc.

The engine 1 has four cylinders 7.
Each cylinder 7 is provided with an intake valve (the above-mentioned intake valve) 9 which is opened and closed by a high speed compatible cam, and an exhaust valve 11, and an intake system 1a of the engine 1 is provided with a throttle valve 13 as a pressure adjusting valve. It is set up. Then, the throttle valve 13 changes the throttle opening degree by controlling the drive of the throttle actuator 15. An exhaust pipe 1b is connected to each exhaust valve 11.

Each intake port 17 branched from the intake system 1a communicates with each cylinder 7, and an intake control valve 19 is provided inside each intake port 17. Each intake control valve 19 independently controls the opening degree of the intake port 17 for each cylinder by controlling the drive of the R / S actuator 21. Further, in the downstream portion 17a of the intake port 17 from the intake control valve 19,
An injector 23 for injecting fuel is provided.

In the engine 1, each cylinder 7 is used as a detector.
Crank angle sensor 25 that outputs a pulse signal when the piston is positioned at the top dead center (TDC), a rotation speed sensor 27 that outputs a pulse signal at each predetermined crank angle, and a sensor that detects torque or combustion for each cylinder. 29 (for example, an in-cylinder pressure sensor, a torque sensor, a knock sensor), a sensor 31 (for example, an intake pipe internal pressure sensor) that detects an air amount for each cylinder, a load detection unit 33 (for example, an accelerator sensor) that detects a load state, noise or vibration. Various sensors such as a noise / vibration detecting means 35 for detecting the noise and an emission detecting means 37 for detecting the emission state are provided.

Further, the engine 1 has an injector 23
Injection control means 3 for controlling the injection amount and injection timing by
9, ignition timing control means 41 for controlling ignition timing, supercharging means 43 for supercharging intake air, learning control means 45 for performing learning control according to operating conditions, intake air heating means 47 for heating intake air, Various control means such as a cooling water temperature adjusting means 49 for adjusting the temperature of the cooling water are provided.

The ECU 5 includes a CPU 5a, a ROM 5b and an R
It is configured as an arithmetic logic circuit centering on AM5c,
It is connected to the input / output unit 5e via the common bus 5d and performs input / output with the outside. Detection signals from the sensors 25 to 37 and signals from the control means 41 to 49 are input to the CPU 5a from the input / output unit 5e. The CPU 5a uses a rotary solenoid actuator (R) of the throttle actuator 15 and the intake control valve 19 via the input / output unit 5e.
/ S actuator) 21, the supercharging means 43, and the intake air heating means 47. Further, the ECU 5 detects the opening / closing period of the intake valve 9 of each cylinder 7 based on the signals from the crank angle sensor 25 and the rotation speed sensor 27.

Next, the intake control valve 19 and the R / S actuator 21 will be described with reference to FIGS. 3 is a sectional view showing the structure of the intake control valve 19 and the R / S actuator 21, FIG. 4 is a sectional view taken along line 4-4 in FIG. 3, and FIG. 5 is an explanatory view showing the operation of the intake control valve 19. is there.
As shown in FIG. 3, the intake control valve 19 includes a butterfly-type circular valve plate 50 provided inside the intake port 17.
The circular valve plate 50 is rotatably supported by a support shaft 51, and swings around the support shaft 51 in a non-contact manner with a very narrow clearance with respect to the wall surface of the intake port 17 (see FIG. 5). It should be noted that one end of the support shaft 51 is supported by the intake port 17 by a bearing 53, and the other end of the support shaft 51 is R / S.
It is connected to the actuator 21.

The R / S actuator 21 includes a support shaft 57,
Magnet member 59, electromagnetic coils 61, 63, permanent magnet 65,
67 and the like. The support shaft 57 is rotatably supported in the casing 55, and supports the support shaft 51 of the intake control valve 19.
Connected to. A magnet member 59 is fitted on the outer periphery of the support shaft 57. Magnetic poles having different polarities are formed on the magnet member 59 symmetrically with respect to the circumferential direction. A pair of electromagnetic coils 61, 63
Are provided on the inner wall of the casing 55 with the magnet members 59 facing each other. Further, the pair of permanent magnets 65, 67 are provided on the inner wall of the casing 55 so as to face each other with the magnet member 59 in between and to be orthogonal to the pair of electromagnetic coils 61, 63.

Next, the control circuit for the electromagnetic coils 61 and 63 will be described. As shown in FIG. 6, the control circuit has four FETs.
This circuit includes a known chopper drive circuit including 70A, 70B, 70C, 70D (transistors may be used), a DC power supply 71, and the like. A driver (not shown) for this control circuit is provided on the ECU 5 side. The electromagnetic coils 61, 63
Has one end connected in series. The other end of the electromagnetic coil 61 is F
It is connected between the ET 70A and the FET 70B, and the other end of the electromagnetic coil 63 is connected between the FET 70C and the FET 70D.

The intake control valve 19 controlled by the above control circuit basically operates as follows. The timing chart of FIG. 7 shows the relationship between the input signal of the driver, the source voltage of the FETs 70A to 70D, and the drive voltage. When an “H” signal with a high voltage level is input to the driver, the driver
The source voltage of the ET 70B, 70C is set to the low level "L" level, the source voltage of the FET 70A is set to the high voltage level "H" level, and the source voltage of the FET 70D is set between the "H" and "L" levels. The control for switching by the PWM control is executed. Therefore, a positive drive voltage is applied, and a current having a magnitude determined by the duty ratio {= T3 / (T2 + T3)} flows from the point a to the point b in FIG. 63 generates a magnetic force according to the magnitude of the current. And the electromagnetic coil 6
Magnetic poles formed by 1, 63 and permanent magnets 65, 67
The magnet member 59 swings to a position determined by the magnetic poles formed by. As a result, the support shaft 57 integrated with the magnet member 59 swings, and the circular valve plate 50 swings toward the fully open position shown by the chain double-dashed line in FIG. Swing amount (open stable position) is Du
It is changed by changing the ty ratio.

Further, the driver has a low voltage level "L".
When a signal is input, the driver is FET 70A, 70D
Is set to the “L” level, the source voltage of the FET 70C is set to the “H” level, and the source voltage of the FET 70B is switched between the “H” and “L” levels by PWM control. Therefore, a negative drive voltage is applied, and a current having a magnitude determined by the duty ratio {= T6 / (T5 + T6)} flows from the point b to the side a in FIG. Rocks in the direction. As a result, the circular valve plate 50 swings toward the fully closed position shown by the chain double-dashed line in FIG. The swing amount (closed stable position) is changed by changing the Duty ratio.

Further, when the power supply to the electromagnetic coils 61, 63 is cut off, the magnet member 59 is held only by the magnetic poles of the permanent magnets 65, 67. Therefore, the circular valve plate 50 swings to the neutral position (half-open position) as shown by the solid line in FIG. The neutral position is a stable position of the rotor magnet and control by the cogging torque (detent torque) when the R / S actuator 21 is not energized.

Therefore, in the above configuration, the stable open position of the intake control valve 19 is determined by the period T2 and the period T3, and when the period T3 is long, the fully open state is established and the period T3.
As is shortened, it stabilizes at the position close to the half open state. Then, when no power is supplied, that is, when the period T3 = 0, the neutral position, that is, the half open state is set. Intake control valve 19
When is set to the open position between the neutral position and the fully closed position, the ratio of the periods T5 and T6 is changed. The longer the period T6, the more stable the position is when it approaches the fully closed state. By changing the duty ratio in this way, the intake control valve 19 can be set to an arbitrary opening.

Note that the rising characteristics of the intake control valve 19 are determined during the periods T1 and T4. 7 is a signal input to the driver from the CPU 5a in order to select the swing direction of the circular valve plate 50 from the open side and the closed side. Also, each of the above periods T1 to T6 for controlling the switching of No. 2 and controlling the swing amount from the neutral position of the circular valve plate 50 is determined by a control signal (not shown) input from the CPU 5a to the driver.

In the intake control device of the present embodiment constructed as described above, under the operation of the CPU 5a, a full-open control for controlling the intake control valve 19 to the fully open state is performed at the time of starting the engine 1 or at a high rotation speed. During other operations, the opening / closing control for opening / closing the intake control valve 19 for each cylinder 7 is executed in synchronization with the rotation of the engine 1 (specifically, the opening / closing state of the intake valve 9 of each cylinder 7). It

That is, first, each cylinder 7
1. The intake valve 9 of the engine 1 is optimally opened and closed without generating pumping loss or backflow of intake air.
Since it is not necessary to perform the opening / closing control of the intake control valve 19 at the time of high rotation of the engine and at the time of high load, and it is necessary to secure the startability of the engine 1 at the time of starting the engine 1, the intake control valve 19 is always fully opened. Full open control is performed to control the position to secure the intake passage.

On the other hand, at the time of partial load of the engine 1 in which the amount of depression of the accelerator pedal is between the minimum and the maximum, the intake port is operated by interlocking the throttle valve with the accelerator pedal, as in an engine without the intake control valve 19. 17
When the engine is fully opened, the intake port 17 becomes a negative pressure, pumping loss occurs, and fuel consumption deteriorates. Therefore, when the engine 1 is partially loaded, the throttle valve 13 is fully opened from the depression amount of the accelerator pedal. The opening and closing control is performed so that the intake control valve 19 is closed earlier than the intake valve 9 is closed during the opening period of the intake valve 9. In other words, the occurrence of pumping loss is suppressed by controlling the intake air amount according to the intake time instead of controlling the intake pressure by the throttle valve 13 such as in an engine not equipped with the intake control valve 19.

When the engine speed is low and the closing timing of the intake control valve 19 shifts in the advance direction, the intake control valve 1
After closing 9, the intake air may be adiabatically expanded to lower the intake air temperature and deteriorate combustion. Therefore, at the time of partial load and low engine speed, in order to reduce the adiabatic expansion section of intake air, the intake control valve 19 is controlled from the fully open position to the closed side so that the intake control valve 19 is at the fully open position. The closing timing of the intake control valve 19 is delayed as compared with the case where the intake control valve 19 is controlled to.

That is, when the engine 1 is partially loaded, the throttle valve 13 is fully opened to suck air into the cylinder at a high intake pressure, so that pumping loss can be prevented and the intake control valve 19 can be opened. When the intake control valve 19 is closed from the fully open position and the closing timing of the intake control valve 19 is delayed compared to when the intake control valve 19 is fully opened, the intake air amount is secured and the intake air is adiabatically expanded. Suppress it.

Further, when the intake control valve 19 is set to the opening closer to the closed side than the full opening, the opening is not fixed, but a predetermined opening determined from the required intake air amount and the required valve closing timing. It is also possible to obtain the optimum valve closing timing at which a high engine torque can be obtained. As a result, the closing timing of the intake control valve 19 can be delayed as compared with the case where the intake control valve 19 is driven only by full opening and full closing.
Combustion deterioration can be prevented, and the intake control valve 19 can be closed at a desired valve closing timing, and a high engine torque can be obtained.

When performing the opening / closing control of the intake control valve 19, the CPU 5a sets the PWM signal periods T2 and T3 for determining the opening / closing timing of the intake control valve 19 and the opening degree when the intake control valve 19 is opened. , And is calculated by using a map that stores the rotational speed and load of the engine 1 stored in advance in the ROM 5b as parameters.

Regarding the opening / closing control of the intake control valve 19, the applicant of the present application previously filed Japanese Patent Application No. 3-5272.
No. 1 and Japanese Patent Application No. 3-54890 are described in detail, so further explanation is omitted here. As described above, in the intake control device of the present embodiment, the fully open control and the open / close control of the intake control valve 19 are executed according to the rotation speed and the load of the engine 1. In this case, the opening degree of the intake control valve 19 is changed. If the drive condition of the R / S actuator 21 (that is, the above-described periods T2 and T3) that determines the R / S actuator 21 is set uniformly using the map or the like, R / S may be changed depending on the operating state of the engine 1.
The battery power used to energize the S actuator 21 may be uselessly consumed.

That is, for example, in the low engine speed range of the engine 1, since the intake air amount is small, the engine 1 is required even if the opening degree during the period when the intake control valve 19 is open is slightly closed from the fully open position to the neutral position side. Can supply a large amount of intake air. Further, even when the engine 1 is rotating at high speed, there is a region where the intake air amount required for the engine 1 can be supplied even if the intake control valve 19 is slightly closed from the fully open position to the neutral position side. This also applies to the opening / closing control when the engine 1 is partially loaded. Therefore, if the periods T2 and T3, which are drive conditions that determine the opening degree of the intake control valve 19 when the valve is opened, are uniformly set only by the rotation speed and load of the engine 1, the R / S actuator 21 is driven. Power may be wasted.

Therefore, in the present embodiment, the driving condition setting process for setting the above-mentioned periods T1 to T6, which is the driving condition of the R / S actuator 21, is executed as shown in FIG. The energizing current of the R / S actuator 21 is minimized within a range that does not affect the power consumption of the R / S actuator 21. The drive condition setting process will be described below.

The drive condition setting process shown in FIG.
In a, it is a process executed as an interrupt process at every predetermined time. When the process is started, first in step 110,
The current rotational speed NE of the engine 1 obtained based on the detection signal from the rotational speed sensor 27 is read, and in the following step 120, whether the rotational speed of the engine 1 is within a predetermined range NE ± α for a predetermined time or more. By determining whether or not the engine 1 is rotating at a constant speed, it is determined.

If it is determined in step 120 that the engine 1 is not rotating at a constant speed, step 13
After shifting to 0, the periods T1 to T6 which are the driving conditions of the intake control valve 19 are read from the preset map based on the operating state of the engine 1, that is, the rotation speed and the load, and in the following step 140, The driver is instructed to read the periods T1 to T6, and the process is once ended.

If the intake control valve 19 is being fully opened, it is not necessary to close the intake control valve 19. Therefore, in step 130, the driving conditions for this, that is, the periods T4 to T6 are not read. By the processing of step 140, the driver is not instructed to perform the periods T4 to T6.

On the other hand, if it is determined in step 120 that the engine 1 is rotating at a constant speed, the process proceeds to step 150, and the rotation speed NE read in step 110 is stored as the reference rotation speed NE1. And the following step 1
At 60, the periods T2 and T3, which are drive conditions that determine the opening degree when the intake control valve 19 is opened, are changed to the neutral position side (that is, the close side) of the intake control valve 19. That is, the intake control valve 1
The open stable position of 9 is determined by the period T2 and the period T3, and the opening becomes larger as the period T3 is longer. Therefore, in this step 160, the period T3 is set to the minimum variable unit T
The duty ratio when the intake control valve 19 is opened is reduced by shortening the period T2 by the minimum variable unit T0 to reduce the energizing current of the R / S actuator 21,
As a result, power consumption is reduced. The minimum variable unit T0 is a minimum unit in which the periods T2 and T3 can be changed. For example, when the periods T2 and T3 can be changed in units of 1 μsec., T0 = 1 μsec.

Next, in the following step 170, the driver is instructed of the changed driving conditions, and in the following step 180, the same as in the above step 110,
The current rotational speed NE of the engine 1 is read. Then, in the following step 190, the read latest rotation speed NE is a value obtained by subtracting the rotation fluctuation allowable rotation speed β from the reference rotation speed NE1 set in step 150 (NE
It is judged whether or not it is less than 1−β), and NE ≧ (NE1−
If β), go to step 160 again and execute R / S
The drive duty ratio of the actuator 21 is further reduced. As a result, the intake control valve 19 is gradually closed.

On the other hand, in step 190, NE <(NE
1-β), the intake characteristic of the engine 1 is judged to be affected by the reduction of the drive duty ratio of the R / S actuator 21, and the process proceeds to step 200. In order not to affect the intake characteristic, the period T3 is extended by the minimum variable unit T0 and the period T2 is increased.
Is shortened by the minimum variable unit T0, thereby slightly increasing the duty ratio when the intake control valve 19 is opened. Then, in the following step 210, the driver is instructed of the changed driving condition, and the process is once ended. As a result, when the intake control valve 19 is driven in the opening direction from the neutral position, the intake control valve 19 is controlled to the most closed position within a range that does not affect the intake characteristic of the engine 1.

During the periods T2 and T3 set in step 200, the RAM is operated by the learning control means 45.
5c, the operating state of the engine 1 becomes the same as the present operating state, and at the time of the next control, step 130
Then, the periods T2 and T3 written in the RAM 5c are read. That is, in the present embodiment, the power consumption after updating the periods T2 and T3 can be further reduced by learning the periods T2 and T3 after the reduction of the drive duty ratio.

Further, the above steps 160 to 19
When the period T2 and T3 are updated by a series of processes of 0, the engine 1 such as the accelerator pedal depression amount is updated.
When the operating state of No. 1 changes, it is necessary to reset the control condition of the intake control valve 19 according to the operating state. Therefore, the drive condition setting process is temporarily ended by an interrupt process (not shown), and then the step The process starts from 110.

As described above, in the intake control device of the present embodiment, as shown in FIG. 9, the rotational speed of the engine 1 stabilizes at a predetermined rotational speed (time t1), and that fact is detected (time point). t2) and thereafter, by gradually decreasing the period T3 that determines the drive duty ratio of the R / S actuator 21 when the intake control valve 19 is opened, and gradually increasing the period T2, the drive duty ratio is increased. Gradually reduce the intake control valve 19 to the neutral position side,
When the rotation speed of the engine 1 is reduced by this, the fact is detected (time point t3), and the period T3 and the period T2 are corrected in the reverse direction by the minimum variable unit T0.
The drive duty ratio of the / S actuator 21 is increased by the minimum variable unit (time point t4) to prevent the rotation speed of the engine 1 from decreasing. The operation of updating the drive duty ratio is executed for each operating condition of the engine 1, and for each operating condition, within a range that does not affect the rotation of the engine 1 (in other words, the intake characteristic of the engine 1 is affected. The minimum drive duty ratio is set within a range not given. In FIG. 9, the above-described operation is shown in four patterns for each rotation speed.

As a result, as shown in FIG. 10, each cylinder # 1
~ Even when the intake control valve 19 of # 4 is controlled to be fully opened at all times, and as shown in FIG. 11, when the intake valve 9 of each cylinder # 1 to # 4 is opened, the intake control valve 19 is opened. A diagram in which the opening degree of the intake control valve 19 is set in accordance with the operating state of the engine 1 by a preset map as shown by the solid line in the drawing even during the opening / closing control of the intake control valve 19 for early closing Compared to the opening indicated by the dotted line in
It will be controlled to the closing side within a range that does not affect the intake characteristic of the engine 1.

Therefore, according to the intake control device of this embodiment,
R / S without affecting the intake characteristics of the engine 1.
The drive duty ratio of the actuator 21 can be reduced to suppress the energization current, and the R / S
The power consumption of the actuator 21 can be reduced.

Here, in the above embodiment, the intake control valve 19
R / S by controlling the opening when the valve is opened
Although the one that reduces the power consumption of the actuator 21 has been described, when the intake control valve 19 is fully closed during the opening / closing control of the intake control valve 19, the opening degree is controlled to the neutral position side. The power consumption of the / S actuator 21 can be further reduced.

That is, as shown in FIG. 5, the intake control valve 19 ensures that the intake port 17 can be closed even when the circular valve plate 50 overshoots when the valve is closed.
Since the overshoot allowable region is set, if the overshoot of the circular valve plate 50 can be suppressed by the driving condition of the R / S actuator 21 when the intake control valve 19 is closed, etc. The intake port 17 can be closed without controlling the fully closed position. In this case, the period T5 when the intake control valve 19 is fully closed is made large and the period T6 is made small.
The drive duty ratio of the R / S actuator 21 can be made smaller than usual to further reduce the power consumption.

In this way, the swing angle at the time of opening / closing control of the intake control valve 19 is reduced from the total opening / closing angle of 90 ° shown in FIG. 5 by 1 ° on the open side and the closed side by 2 ° in total. In such a case, the effect of reducing the power consumption of the R / S actuator 21 was obtained by experiments. From the experimental results, as shown in Table 1, the power consumption of the R / S actuator 21 decreases as the swing angle of the intake control valve 19 decreases and the drive duty ratio of the R / S actuator 21 decreases. It can be seen that the power consumption can be reduced.

[0055]

[Table 1]

Further, in the above embodiment, R / R is controlled by so-called feedback control, in which the opening degree of the intake control valve 19 is controlled to the closing side while confirming that the rotation speed of the engine 1 is stable. Although the power consumption of the S actuator 21 is configured to be reduced, for example, a valve opening degree that is the smallest within a range that does not affect the intake characteristic of the engine 1 is set in advance by an experiment, and the actual control is performed as follows. The full open control and the open / close control of the intake control valve 19 may be executed based on the experimental data. When performing feedback control as in the above embodiment, the torque of the engine 1 is detected instead of the rotation speed of the engine 1,
A change in the intake characteristic of the engine 1 may be detected from the detected change in the engine torque.

Next, in the above embodiment, the intake control valve 1
Drive duty of R / S actuator 21 when valve 9 is opened
By reducing the ratio, the R / S actuator 21
However, the intake characteristic of the engine 1 is determined by the open / close state of the intake control valve 19 when the intake valve 9 is opened, and how the intake control valve 19 is changed when the intake valve 9 is closed. Since desired intake characteristics can be obtained even with control, by changing the energized state of the R / S actuator 21 in the direction of reducing the power consumption when the intake valve 9 is closed, the R / S is reduced.
It is also possible to reduce the power consumption of the actuator 21.

Hereinafter, by changing the energization state of the R / S actuator 21 when the intake valve 9 is closed, the power consumption thereof is reduced by specific examples (1) to
(5) will be described. (1) When the intake control valve 19 is fully opened, the intake control valve 19 may be controlled to the fully open position when the intake valve 9 is opened.

Therefore, when the intake control valve 19 is fully opened, as shown in FIG. 12, from the time t01 at which the intake valve 9 starts opening to the time t02 at which the intake valve 9 becomes fully closed, the intake control valve 19 is opened. The intake control valve 19 is controlled to the neutral position (half-open position) by stopping the energization of the R / S actuator 21 when the intake valve 9 is closed within a range in which the intake valve 9 can be controlled to be fully opened.

As a result, as compared with the case where the intake control valve 19 is controlled to the fully open state as shown by the dotted line in FIG.
It is possible to reduce the power consumption of the R / S actuator 21 by the amount indicated by the diagonal lines in FIG. (2) When controlling the opening and closing of the intake control valve 19, the intake control valve 19 can be controlled to a desired opening when the intake valve 9 is opened, and the intake control valve 19 is closed before a predetermined crank angle at which the intake valve 9 is closed. It is sufficient that the intake control valve 19 can be kept closed until the intake valve 9 is closed.

Therefore, during the opening / closing control of the intake control valve 19, as shown in FIG. 13, from the time t11 when the intake valve 9 starts to open to the time t12 when the intake valve 9 becomes fully closed, The intake control valve 19 is controlled to the neutral position (half-open position) by stopping the energization of the R / S actuator 21 when the intake valve 9 is closed within a range in which the intake valve 19 can be controlled to a desired opening degree.

As a result, the power consumption of the R / S actuator 21 can be reduced by the amount shown by the diagonal lines in FIG. 13, as compared with the case where the intake control valve 19 is simply opened and closed as shown by the dotted line in FIG. It will be possible. (3) For the same reason as (2) above, the intake control valve 19
During the opening / closing control of the intake valve 9, as shown in FIG. 14, the intake valve 9 starts from time t21 when the intake valve 9 starts opening.
Until the time t22 when the intake valve 9 is fully closed, the drive duty ratio of the R / S actuator 21 when the intake valve 9 is closed is reduced within a range in which the intake control valve 19 can be controlled to a desired opening degree. To reduce.

As a result, when the intake valve 9 is fully closed, the intake control valve 19 is controlled to a predetermined opening between fully closed and half open, and the intake control valve 19 is simply opened as shown by the dotted line in FIG. It is possible to reduce the power consumption of the R / S actuator 21 as much as the shaded area in FIG.

(4) The R / S actuator 21 of this embodiment can switch the open / close state of the intake control valve 19 by switching the energization direction of the electromagnetic coils 61, 63. As shown by the solid line, the rise of the current is delayed due to the characteristic of the inductance, and the current is not stabilized until a predetermined time ΔT has elapsed from the times t31 and t32 when the energizing direction was switched. On the other hand, when the intake control valve 19 is held at a constant opening,
As shown by the dotted line in FIG. 5, such rising delay of the current does not occur, so that the power consumption increases by the amount shown by the diagonal line in FIG.

Therefore, as for the power consumption of the R / S actuator 21, the larger the number of times the R / S actuator 21 is switched in the energizing direction per unit time, in other words, the larger the number of times the intake control valve 19 is opened / closed per unit time. The smaller it gets. Therefore, when the intake control valve 19 is fully opened, as shown in FIG.
As shown in, the time t42 at which the intake valve 9 is fully closed from the time t41 at which the intake valve 9 starts to open.
Until then, the energization direction of the R / S actuator 21 when the intake valve 9 is closed is repeatedly switched within the range in which the intake control valve 19 can be controlled to be fully opened, and the intake control valve 19 is opened and closed.

As a result, the power consumption can be reduced by the amount of the delay in the rising of the current generated when the energizing direction of the R / S actuator 21 is switched. In this case,
Since the intake control valve 19 is repeatedly opened and closed when the intake valve 9 is closed, the circular valve plate 50 of the intake control valve 19 is
It is also possible to prevent deposits and the like from adhering to.

(5) For the same reason as the above (4), during the opening / closing control of the intake control valve 19, as shown in FIG. 17, the intake valve 9 is in the fully closed state from the time t51 when the intake valve 9 starts opening. Until time t52, the intake control valve 19 is opened and closed by repeatedly switching the energization direction of the R / S actuator 21 when the intake valve 9 is closed within a range in which the intake control valve 19 can be controlled to a desired opening degree.

As a result, similarly to the above (4), the power consumption can be reduced by the amount of the delay in the rising of the current generated when the energization direction of the R / S actuator 21 is switched, and the circular valve of the intake control valve 19 can be reduced. It is also possible to prevent deposits and the like from adhering to the plate 50.

Next, as described in (4) and (5) above, when the intake valve 9 is closed, the R / S actuator 21
The control in the case of switching the energization direction of and opening and closing the intake control valve 19 will be described in more detail. The current waveform shown in FIG. 15 is an experiment in which the intake control valve 19 is switched from fully closed to fully open and fully open to fully closed at times t31 and t32 while the engine 1 is operating at 1200 rpm. As a result, in this case, the time ΔT until the rise delay of the current is stabilized was about 20 msec. This time △
T is determined by the electromagnetic coils 61 and 63 and the power supply voltage, and is not related to the rotation speed of the engine 1.

Therefore, in this case, fully open (or fully closed)
Regardless of the rotation speed of the engine 1, the time required to stabilize the intake control valve 19 in the state once in the fully closed (or fully open) state and again in the fully open (or fully closed) state is 4
It becomes 0 msec. (= 2 × 20 msec.). However, as is clear from FIG. 15, the energization current of the R / S actuator 21 has a rise delay of 10 msec. And is almost a value close to the fully-open or fully-closed holding current. There is no problem even if the minimum holding time is set to 10 msec. (Even if it is 10 msec. Or less, there is a sufficient power consumption reduction effect).

Based on the above, when the rotational speed of the engine 1 is 1000 rpm and 3000 rpm, the energizing direction of the R / S actuator 21 is switched,
The power consumption was measured. The results are shown in Table 2. In Table 2, the valve opening rate represents the ratio of the opening command time per cycle {= fully opening command time / (fully opening command time + fully closing command time)}.

[0072]

[Table 2]

From the above measurement results, it was found that the power consumption of the R / S actuator 21 can be reduced by providing a valve closing period of 10% at 1000 rpm and 20% at 3000 rpm for 30 w at full opening. . Then R /
When the energization direction of the S actuator 21 is switched to reduce power consumption, the minimum holding time when switching the energization direction is constant regardless of the rotation speed of the engine 1.
When actually performing control, the number of times of switching in the valve closing period of intake valve 9 is set from this minimum holding time as follows.

First, when the minimum holding time is 10 msec.
To open and close the intake control valve 19 once, 20 msec. (=
2 × 10 msec.) Is required. Considering the rotation speed of the engine 1 and the time of one cycle, one cycle = 7
20 ° C. A, the intake valve 9 opening period is 25
If the temperature is 0 ° C, the closing period of the intake valve 9 is 4
70 ° C. A (= 720-250), and it becomes a problem how many msec. Of 470 ° C. A at each rotation speed.

How many msec. Of 720 ° C. A is 120,000 (msec ..), where X is the rotation speed of the engine 1.
rpm) /Xr.pm, T = (120,000 / X) × (470/720) when the time of 470 ° C. A at the rotation speed X is Tmsec.

Therefore, based on the above calculation result Tmsec., When the intake valve 9 is closed (at 470 ° C. A),
If the number of times of 20 msec. Is obtained, the number of times the R / S actuator 21 is switched in the energization direction can be set. For example, when the rotation speed of the engine 1 is 1200 rpm, 720 ° C.A is 100 msec. And 470 ° C.A is 47 msec. Therefore, the opening / closing operation is performed twice while the intake valve 9 is closed. You can do it.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a configuration of the present invention.

FIG. 2 is a block diagram showing an entire system of an engine to which an intake control device according to an embodiment of the present invention is applied.

FIG. 3 is a cross-sectional view showing structures of an intake control valve and an R / S actuator.

FIG. 4 is a sectional view taken along line 4-4 of FIG.

FIG. 5 is an explanatory diagram illustrating an opening / closing operation of an intake control valve.

FIG. 6 is a circuit diagram showing a control circuit of an R / S actuator.

FIG. 7 is a timing chart showing the relationship between the input signal of the control circuit of the R / S actuator and the drive voltage.

FIG. 8 is a flowchart showing a drive condition setting process executed by a CPU in the ECU.

FIG. 9 is a time chart showing changes in the drive duty ratio and the intake control valve opening of the R / S actuator controlled by the drive condition setting process.

FIG. 10 is an explanatory diagram showing a control state of an intake control valve by a drive condition setting process executed during full closing control.

FIG. 11 is an explanatory diagram showing a control state of an intake control valve by a drive condition setting process executed during opening / closing control.

FIG. 12 is an explanatory diagram showing the control state of the intake control valve when the energization of the R / S actuator is stopped during full-open control as another embodiment.

FIG. 13 is an explanatory diagram showing a control state of the intake control valve when the energization of the R / S actuator is stopped during the opening / closing control as another embodiment.

FIG. 14 is an explanatory diagram showing a control state of the intake control valve when the drive duty ratio of the R / S actuator is reduced during opening / closing control as another embodiment.

FIG. 15 is an explanatory diagram showing a change in an energized current when the energizing direction of the R / S actuator is switched.

FIG. 16 is an explanatory diagram showing a control state of the intake control valve when the energization direction of the R / S actuator is switched during full-open control as another embodiment.

FIG. 17 is an explanatory diagram showing a control state of the intake control valve when the energization direction of the R / S actuator is switched during opening / closing control as another embodiment.

[Explanation of symbols]

1 ... Engine 3 ... Intake control unit 5 ... ECU 5
a ... CPU 5b ... ROM 5c ... RAM 7 ... Cylinder 9 ... Intake valve 13 ... Throttle valve 15 ... Throttle actuator 17 ... Intake port 19 ... Intake control valve 21 ... R /
S actuator

Claims (2)

[Claims] 1. An intake control valve provided in an intake passage of an internal combustion engine and, when not energized, holding the intake control valve in a neutral position where the intake passage is half-opened, and when energized, in an energizing direction according to an energizing current. A rotary solenoid actuator that opens and closes the intake control valve in a corresponding direction, and opens and closes the intake control valve in synchronization with the opening and closing of the intake valve of the internal combustion engine that is driven to open and close in synchronization with the crank angle of the internal combustion engine. An intake control device for an internal combustion engine, comprising: an intake control means that is driven and that adjusts the opening / closing timing of the intake control valve according to the operating state of the internal combustion engine, in accordance with an opening / closing command from the intake control means. An energization control unit that controls energization of the rotary solenoid actuator to open and close the intake control valve, wherein the low voltage is applied during a period in which the intake valve is closed. Intake air control system for an internal combustion engine, characterized in that it comprises a current control means for reducing the energization amount of the re solenoid actuator. 2. An intake control valve provided in an intake passage of an internal combustion engine and, when de-energized, the intake control valve is held in a neutral position where the intake passage is half-opened. A rotary solenoid actuator that opens and closes the intake control valve in a corresponding direction, and opens and closes the intake control valve in synchronization with the opening and closing of the intake valve of the internal combustion engine that is driven to open and close in synchronization with the crank angle of the internal combustion engine. An intake control device for an internal combustion engine, comprising: an intake control means that is driven and that adjusts the opening / closing timing of the intake control valve according to the operating state of the internal combustion engine, in accordance with an opening / closing command from the intake control means. An energization control unit that controls energization to the rotary solenoid actuator to open and close the intake control valve, and is set to a low value within a range where required intake characteristics are obtained. Intake air control system for an internal combustion engine, characterized in that the energizing current comprises current control means for energizing the said rotary solenoid actuator.