JPH0286920A - Intake air controller for internal combustion engine - Google Patents

Abstract

PURPOSE:To increase a counterflow checking effect as well as to make improvements in torque and fuel consumption by driving an intake control valve for its closing independently of rotation of an internal combustion engine according to timing for checking a counterflow of intake air being produced in the latter half of a valve opening period in an intake valve. CONSTITUTION:An intake control valve M4 is set up in an intake passage M3 being interconnected to a cylinder M2 of an internal combustion engine M1, and this intake control valve M4 is opened or closed by a driving means M5. On the other hand, timing for checking any counterflow of intake air being produced in the latter half of a valve opening period in an intake valve 8 should be set on the basis of rotational position data of the engine M1 detected by a rotational position detecting means M6 and speed data of the engine M1 detected by a speed detecting means M7. Then, according this timing, it is controlled by a driving control means M9 so as to have the intake control valve M4 closed by the driving means M5.

Description

Detailed Description of the Invention Object of the Invention [Industrial Field of Application] The present invention relates to an intake control valve that is arranged in each intake passage communicating with each cylinder separately from the intake valves of the cylinders of an internal combustion engine. The present invention relates to an air intake control device effective for opening and closing.

[Prior Art] Conventionally, it has been considered to prevent backflow of intake air in the intake passage of an internal combustion engine by providing an intake control valve as described above for each intake passage.

In other words, at the start of the intake stroke of an internal combustion engine, valve overlap causes burned gas in the cylinders and exhaust passages to flow back into the intake passage, reducing the intake air filling efficiency. Filling efficiency sometimes decreased due to backflow. Therefore, it has been considered to use an intake control valve to prevent the backflow of intake air and improve the filling efficiency of intake air, thereby increasing the torque of the internal combustion engine and improving fuel efficiency.

As a device for switching the opening and closing of the intake control valve, an internal combustion engine has been proposed (Japanese Patent Laid-Open No. 148932/1983) in which the intake control valve is opened and closed by a cam linked to the rotational movement of the internal combustion engine. This intake control valve is capable of shifting its opening/closing timing back and forth depending on the rotational speed of the internal combustion engine using an adjustment mechanism. This adjustment mechanism is provided for the following reasons.

That is, since the intake air backflow prevention timing depends on the reciprocating time of the advancing pressure wave at the speed of sound, when the valve is opened and closed in conjunction with the rotation of the internal combustion engine, the timing of closing the valve is delayed at low rotation speeds. This is to correct this delay and appropriately prevent backflow.

[Problems to be Solved by the Invention] However, even if the valve closing timing can be corrected mechanically, in a configuration that is linked to the rotational movement of the internal combustion engine, changes in the opening area of the intake control valve also affect the rotational behavior of the internal combustion engine. This problem has not been solved yet.

Next, this inconvenience will be explained. FIG. 15 shows an intake control valve for each cylinder and an opening/closing timing chart of the intake valve in conjunction with a four-cylinder internal combustion engine.

Here, the solid line represents the change in the opening area of the intake control valve Cv when the internal combustion engine is running at high speeds, and the dotted line represents the change in the opening area of the intake control valve Cv when the internal combustion engine is running at low speeds.
The one-dot chain line represents the change in the opening area of the intake valve Iv.

In the high speed range of the internal combustion engine, the closing timing of the intake valve Iv is optimally matched, so the intake control valve Cv only needs to be opened and closed so as not to restrict the intake air. Therefore, Cvl
As shown in FIG. 2, the intake control valve Cv and the intake valve Iv have almost the same pattern of opening area change. In other words, there is no problem with the backflow of intake air. Furthermore, since the patterns match, there is no problem with the intake throttle of the intake control valve Cv.

However, in the low rotation range, although the timing of the reverse flow itself does not change, the movement of the intake valve Iv of the internal combustion engine slows down and is delayed to some extent. Therefore, as shown by Cv2, the backflow cannot be prevented unless the pattern of the intake control valve Cv is shifted to the advance side compared to the pattern of the intake valve Iv. Therefore, an adjustment mechanism works to shift the opening area pattern of the intake control valve Cv toward the advance side. As a result, even if the internal combustion engine rotates at a low speed, the intake control valve Cv can be fully closed at the timing immediately before the intake air on the cylinder side is discharged due to backflow, thereby preventing a decrease in filling efficiency.

However, although this is sufficient for the full closing timing of the intake control valve Cv to prevent backflow, in the section Ta, the opening area of the intake control valve Cv is smaller than that of the intake valve Iv, and conversely, the intake air to the cylinder side is This resulted in the inconvenience of aperture. As a result, the benefits of improved torque and fuel efficiency due to reverse flow prevention were halved.

Such inconveniences were unavoidable as long as an interlocking mechanism with an internal combustion engine was used.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an intake control device that is capable of closing a valve at a suitable timing to prevent backflow, and that does not disturb the intake itself. With the goal.

[Means for Solving the Problems] In order to achieve the above object, the present invention has adopted the configuration shown below as a means for solving the above problems.

That is, the gist of the present invention, as illustrated in the first diagram, includes: an intake control valve M4 which is disposed in an intake passage M33 communicating with the cylinders M2j of the internal combustion engine M1 and is capable of opening and closing the intake passage M3; A driving means M5 for opening and closing the intake control valve M4 independently of the rotation of the internal combustion engine M1, a rotational position detection means M6 for the internal combustion engine M1, and a rotational speed detection means M for the internal combustion engine M1.
7, rotational position data of the internal combustion engine M1 detected by the rotational position detection means M6, and rotational speed detection means M7.
Based on the rotational speed data of the internal combustion engine M1 detected at tZ, a timing is set to prevent the backflow of intake air that occurs in the latter half of the opening period of the intake valve M8, and at this timing,
The present invention is directed to an intake control device for an internal combustion engine, which has a drive control means M9 for driving the intake control valve M4 to be closed by the drive means M5.

[Operation] Since the drive means M5 of the present invention is independent of the rotation of the internal combustion engine M1 and is not interlocked with it, the drive control means M9 restricts the closing drive of the intake control valve M4 to the rotational speed of the internal combustion engine. It can be executed at any time. Therefore, naturally, based on the rotational position and rotational speed of the internal combustion engine M1, the intake valve M
By determining the timing at which backflow occurs in the second half of the valve opening period in step 8 and driving the valve to close accordingly, it is possible to close the valve at a timing that prevents backflow.

Furthermore, the closing speed of the intake control valve M4 can be arbitrarily set in response to the change in the frontage area when the intake valve M8 is closed, and can be particularly controlled at a high speed, and can also be controlled discontinuously.

That is, it is also possible to stop the valve in the valve open state or the valve closed state until it is necessary to drive it again. Therefore, when the timing for backflow prevention is reached, the intake control valve M4, which is in the open state, can be abruptly closed, so that the intake control valve M4 can be abruptly closed even when the internal combustion engine M1 is running at low speeds, and the intake throttle and The intake control valve M4 can be driven to prevent this from happening.

[Embodiment] Next, a preferred embodiment of the present invention will be described in detail based on the drawings. FIG. 2 shows a system configuration of an internal combustion engine equipped with an intake control device according to a first embodiment of the present invention.

As shown in the figure, this system mainly includes a four-cylinder internal combustion engine 1, an intake control unit 3 installed in an intake system 1atZ of this internal combustion engine 1, and an electronic control unit (hereinafter simply referred to as ECU) that controls these. ) Consists of 4. This intake control section 3. Electronic control device 4. A crank angle sensor and a rotational speed sensor, which will be described later, correspond to the intake control device.

The internal combustion engine 1 has four cylinders 5. 6. 7. 8, and each cylinder 5 to 8 has an intake valve 9, 10, 11, 12 which is opened and closed in conjunction with the rotation of the internal combustion engine 1 by a high-speed compatible cam.
are provided, and exhaust valves 13, 14, 15, 16 are also provided. Branched within the intake system la and connected to each cylinder 5 to 8
Intake control valves 21, 22, 23, and 24 are provided in the intake boats 17.1B and 19.20, respectively, which communicate with the intake boats 17.1B and 19.20. They are connected and driven to open and close by an actuator 27. Here, the intake control valves 21 to 24 are driven to open and close by the actuator control of the ECU 4, independently of the opening and closing of the intake valves 9 to 12, as described below.

The internal combustion engine 1 includes, as a detector, a crank angle sensor 29a that outputs a pulse signal when the piston (not shown) of each cylinder 5 to 8 is located at top dead center (TDC), and a crank angle sensor 29a that outputs a pulse signal at every predetermined crank angle. It includes a rotation speed sensor (also serving as a rotation angle sensor) 29b that outputs an output, and a knock sensor 29c that detects the occurrence of knocking in the internal combustion engine 1.

The signals from each of the sensors are manually input to the ECU 4, and the ECO 2 controls the intake control valves 21 to 24 using this manual data and other necessary data.

The ECU 4 is configured as a logic operation circuit mainly including a CPU 4a, a ROM 4b, and a RAM 4C, and is connected to a human output section 4e via a common bus 4d to perform human output with the outside. Detection signals from each of the sensors 29a to 29c are manually input to the CPU 4a from the human output section 4e. On the other hand, the CPU 4a outputs a control signal to the actuator 27 via the human output section 4e.

Next, an example of the intake control valve 21 and the actuator 27 will be described below.

As shown in FIG. 3, the intake control valves 21 to 24 are installed in the intake boats 17 to 20 perpendicularly to the flow direction of the intake air of the intake boats 17 to 20, and are partially cut out with a semicircular cross section. (1) A bearing 33 that pivotally supports the drive shaft 25; and (2) A bolt 37. A device consisting of disc-shaped movable plates 41.42, 43.44 that are rotatable about the shaft 25. The movable plates 41, 43, 44. 4. 2
The cylinders are arranged with a phase shift of 90' in the order of the cylinders.

That is, the movable plates 41 and 44 are arranged with their plate surfaces parallel to each other,
The movable plates 42 and 43 are arranged so that their surfaces are parallel to each other, and the movable plates 41 and 44 and the movable plates 42 and 43 are arranged at right angles.

As shown in FIG. 5, which is an enlarged sectional view taken along the line A-A in FIG. 3, a spherical recess 47 having a diameter larger than the inner diameter is provided in each of the intake boats 17 to 2o. Movable plate 41
44 are rotatably arranged in this spherical recess 47 portion. Therefore, the diameter of the spherical recess 47 is the same as that of the movable plates 41 to 44.
The diameter is slightly larger (for example, several U to several hundred microns larger) than the diameter of.

On the other hand, the actuator 27 is formed as a modification of a so-called PM type stepping motor, as shown in FIG. 4, which is an enlarged sectional view taken along the line B-B in FIG. The inner wall of the casing 27a has a permanent magnet 27b connected to the drive shaft 25, and a permanent magnet 27C fixed around the shaft 27b and magnetized into two poles. Four-pole coils 51, 52, 53, and 54 are arranged to surround the permanent magnet 27c. Specifically, the -phase coils 51 and 52 are aligned in the flow direction of the intake air of the intake boat 17, and the other phase coils 53 and 54 are aligned with the coils 51 and 54 of the other phases.
The magnets 52 are arranged in a direction perpendicular to the arrangement direction of the magnets 52, and surround the permanent magnets 27a. The coils 51 to 54 have a monofilar structure in which a single enameled wire is wound around bobbins 51a, 52a, 53a, and 54a fixed to the inner wall of the casing 27a with bolts 57 or the like.

The control system of the actuator 27 configured in this way is
The circuit diagram shown in the figure is shown below. As shown in the figure, resistors R1, R2, R3, R4 and capacitors CI, C2, C3, C4 are attached to the coils 51 to 54, respectively, and the circuit with the power source E is connected by the ECU 4. Coils 51 and 52 of one phase and coils 53 of the other phase are opposed to each other.
54 to switch the excitation positions of the coils 51 to 54. In this way, the movable plate 4
1 to 44 can be swung by 90 degrees. Further, by changing the circuit of the control system, it is possible to rotate the same shape at a step angle of 90°.

The relationship between the operations of the intake control valves 21 to 24 and the actuator 27 configured as described above will be explained below using a -phase excitation unipolar drive system.

When the coils 51 and 52 are switched to the excited position by the ECU 4, magnetic flux flows from the coil 51 to the coil 52 (or from the coil 52 to the coil 51), and the permanent magnet 2
7c swings in a predetermined direction determined by its magnetic pole (FIG. 6, arrow C or D direction), and at this time, the permanent magnet 27c
Movable plates 41-- connected via drive shafts 27b and 25 to
44 is also the same Ml, Otsu swings. After that, the permanent magnet 27c stops swinging in the stable direction determined by the coil 51.52, and the movable plate 41.44 is oriented in the direction of the intake flow of the intake boat 17.20, and the intake boat 17.20 is opened. be done.

At this time, the movable plate 42.43 is
The intake boats 18.
19 will be closed.

On the other hand, when the coils 53 and 54 are switched to the excited position by the ECU 4, magnetic flux flows from the coil 53 to the coil 54 (or from the coil 54 to the coil 531), and the permanent magnet 27c moves in a predetermined direction (sixth direction) determined by its magnetic pole. figure,
At this time, the movable plates 41 to 44 connected to the permanent magnet 27c also swing at the same time. Thereafter, the permanent magnet 27c stops swinging in the stable direction determined by the coils 53 and 54, and the movable plate 42. 43 is oriented in the air-fuel mixture flow direction of the intake bow) 18.19, and the intake bow) 18.19 is opened. At this time, the movable plate 4
1.44 are oriented at right angles to the intake flow direction of the intake boats 17, 20, and the intake boats 17.20 are closed.

Next, the intake control process executed by the ECU 4 will be explained based on the flowchart of FIG. 7. This intake control process is
It is repeatedly executed after the ECU 4 is started.

First, the current rotational speed Ne of the internal combustion engine 1 is detected (
Step 100). A closing crank angle CLA for closing each intake control valve 21 to 24 is determined from this rotational speed Ne (step 11o). This crank angle CLA
is set so that when the crank angle reaches this angle, the drive current is allowed to flow, and the timing when the intake control valves 21 to 24 are fully closed corresponds to the timing for backflow prevention.

The closing crank angle CLA is measured in advance according to the rotational speed Ne through experiments, and the rotational speed Ne and the closing crank angle CLA are made into a table or map. Based on the table, the closing crank angle CLA is calculated from the rotational speed Ne. You may also ask for An example is shown in Table 1.

Table 1 WOT: Represents the throttle valve fully open state.

The numbers represent crank angles.

Also, since the closing crank angle CLA is proportional to the rotational speed Ne, the closing crank angle CLA at a certain rotational speed Ne is determined at one point, and the closing crank angle CLA corresponding to the rotational speed Ne is calculated every time step 110 is executed. May be used.

Next, the closing crank angle CL obtained in this way
A is stored and saved at a predetermined address in RAM 4c (
Step 120).

Using the closing crank angle CLA stored in this predetermined location, the closing control process shown in the flowchart of FIG. 8 is executed. This process is repeatedly executed at sufficiently short intervals.

First, it is determined whether the crank angle CA detected by the rotational speed sensor 29b has reached the closing crank angle CLA stored in step 120 (step 15).
0).

When the closing crank angle CLA is reached, the actuator 27
A drive current is output to (step 160). That is, the coil of the actuator 27 is excited so that the intake control valves 21 to 24 of the corresponding cylinder are closed. Of course, since all the intake control valves 21 to 24 are linked, the valves other than those to be closed also swing.

Since the internal combustion engine 1 of this embodiment has four cylinders, the closing crank angle CLA is 4 cylinders in one cycle (0° to 720°).
There are two.

This state is shown in the timing chart of FIG.

This timing chart is based on the case where the internal combustion engine 1 is at high rotation speed, for example, 6000 r, p, m. The straight line (solid line) covers the change in the opening area of the intake control valves 21 to 24,
The curve (solid line) represents the change in the opening area of the intake valves 9 to 12, and the curve (-dot chain line) represents the change in the opening area of the exhaust valves 13 to 16.

The closing crank angle CLA corresponds to a1 to a4 in the figure, but is slightly faster. The reason for this is that there is a delay in starting the intake control valves 21 to 24 with respect to the drive current. Therefore, at this crank angle, the drive current to the actuator 27 is switched and output, and the intake control valves 21 to 2 are output each time.
All the movable plates 41 to 44 of No. 4 swing 90 degrees. angle b
1 to b4, the intake control valves 21 to 24 are completely closed. At maximum rotation, the drive current is actually output to the actuator 27 one after another without any break, resulting in continuous oscillation.

Since the four intake control valves 21 to 24 swing together, for example, when the intake control valve 21 of the first cylinder 5 starts to close from al, the intake control valve 22 of the second cylinder 6 and the third cylinder 7
．． 23 begins to open, and the intake control valve 24 of the fourth cylinder 8 begins to close. Since the second and fourth cylinders 6 and 8 are not in the intake stroke, the swinging of the intake control valves 22 and 24 does not affect the intake, but since the intake starts for the third cylinder, the opening and closing operation of the intake control valve 23 is affect. However, since the movable plate 43 of the intake control valve 23 is attached at right angles to the movable plate 41 of the intake control valve 21, the movable plate 43 of the intake control valve 23 is driven open at the same time as the closing operation of the intake valve 11, and there is no possibility of an intake mark.

Next, we will discuss how to improve torque.

The negative pressure wave generated by the opening operation of the intake valves 9 to 12 is transmitted to the intake system 1.
a, returns to the cylinder as a positive pressure wave from a volume system such as a surge tank, and attempts to trace back through the intake system 1a again. By shutting out this positive pressure wave when it exits from the cylinders 5 to 8 to the intake system 1a, the charging efficiency is improved. Therefore, the intake control valves 21 to 24 are set at the timing at which the positive pressure wave returns to the cylinders 5 to 8 and is confined within the cylinder.

Next, in FIG. 10, the internal combustion engine 1 rotates at low speed (for example, 300
0 r, p, m,) is shown. The horizontal axis is the crank angle CA, but in order to match the time scale with that in FIG. 9, the horizontal axis as the crank angle is enlarged from FIG.

In this case, the intake control valve 21 for preventing backflow of intake air
The temporal closing timing of ~24 is affected by the speed of sound, so it usually does not change much. However, since the rotational speed of the internal combustion engine 1 decreases, the closing crank angle CLA (jl to j4) of each cylinder 9 to 12 becomes advanced compared to that at high rotation.

Further, since the swinging speed of the intake control valves 21 to 24 is the same as at high rotation (that is, the driving current is the same), the intake control valves 21 to 24 have a stop period (kl to 112.
2~h3. k3~h4. ) exists. Therefore, the timing chart has a trapezoidal shape.

Here, a comparison will be made with the prior art shown in FIG.

First, both the full open crank angle at high revolutions (bl to b4) and the full open crank angle at low revolutions (jl to j4) are
Fully closed crank angle X at high rotation of the conventional technology shown in Figure 5
1. This is the same setting as the fully open crank angle y1 at low rotation.

However, in the configuration of this embodiment, the intake control valves 21 to 24 are independent of and not linked to the rotation of the internal combustion engine 1, so even if the opening area of the intake valves 9 to 120 changes gradually over time at low rotations, Since the intake control valves 21 to 24 are controlled to swing at a speed that does not change more closely than the actuator 27, the steepness remains unchanged.

Therefore, as shown in FIG. 10, the degree of marking on the intake valves 9 to 12 is very small and does not pose an obstacle to intake. This improves torque and saves fuel.

Of course, the swing speed of the intake control valves 21 to 24 can be adjusted by adjusting the amount of current to the actuator 27, but in this embodiment, the swing speed of the intake control valves 21 to 24 can be adjusted by adjusting the amount of current supplied to the actuator 27.
As shown in the figure, the drive current is set so that there is no period when the intake control valves 21 to 24 are stopped. In this way, it is independent of 10 revolutions of the internal combustion engine, so by selecting the current based on the graph in Figure 11, the intake air does not become throttled and can easily be fully closed at the timing of blocking backflow. The moving speed can be set.

Further, in this embodiment, since one actuator 27 drives all the intake control valves 21 to 24, control and configuration are simplified, leading to cost reduction.

In the above embodiment, there is one actuator 27, but each cylinder 5 to 8N is provided with an actuator 27 so that each intake control valve 21 to 24 can be operated without being restricted by the driving of other intake control valves 21 to 24. , may be driven. That is, the intake control valve 2
The opening times 1 to 24 can be set at any timing before the intake stroke. In the above embodiment, the opening timing coincides with the closing timing of the other intake control valves 21 to 24, so the opening timing cannot be freely selected.

Furthermore, although the actuator 27 is provided at the end on the first cylinder 5 side, it may also be provided between two cylinders, such as between the second cylinder 6 and the third cylinder 7. Furthermore, if necessary, the intake control valve 2
A plurality of actuators may be provided on one drive shaft 25 in order to improve the rocking torque of the shafts 1 to 24.

FIGS. 16(A) to 16(C) show configuration examples in which the actuator is provided between the second cylinder 6 and the third cylinder 7! This is shown. 16th
Figure (A) is a plan view showing the intake control valve and actuator 27-1, (B) is a partially cutaway front view thereof, and (C) is a front view with housing 38-1 removed.

Here, intake control valve 21-1.22-1.23-L 2
4-1 movable plate 41-1.42-1, 431.44-1
is assembled to the drive shaft 25-1 with bolts 37-1 and 39-1. A permanent magnet 2 is located in the center of the drive shaft 25-1.
7 cm1 is fixed, and the drive shaft 25-1 also has bearings 33-1. 33-2. Bearing 33
-1 is fitted and fixed in the cap 34-1.

The other configurations within the actuator 27-1 are the same, so the explanation will be omitted. Actuator 27-1 itself is Pol)
It is fixed to the housing 38-1 at 36-1.

Bush 35-1 fixes bearing 33-2.

In such a configuration, the loads on both sides of the actuator 27-1 are balanced, so that the various parts of the actuator 27-1 are not unevenly worn, and the life of the actuator 27-1 is extended.

The movable plates 41-1 to 44-1 and the housing 3B-1 may be of either a non-contact type or a contact type, as shown in FIG.

In the actuator 27, 27-1, a one-phase excitation driving method is shown, but a two-phase excitation bipolar driving method may be used. The drive control in this case is shown in Table 2, and the state of the actuator 27 is shown in FIG.

It is shown in FIG. A 1-2 phase excitation bipolar drive that can be stopped at the same time is also shown. However, FIG. 17(D) is an explanatory diagram showing that the allowable bound width of the movable plates 41 to 44 when fully closed is in the range of 40 degrees.

In addition, in the case of the two-phase excitation bipolar drive and the one-two phase excitation bipolar drive, the phase of the permanent magnet 27c in the configuration of the actuator 27 is set to have a difference of 45 degrees compared to the one-phase excitation unipolar drive. There is.

According to the 1-2 phase excitation bipolar drive shown in Table 2, 1
Compared to phase excitation unipolar drive or two phase excitation bipolar drive, intermediate stop is possible, and the intake control valves 21 to 24
can be stopped in a half-open state. Such a function enables step-like control as shown in FIG. 12 or FIG. 14, which will be described later.

Furthermore, although the actuator 27 is of a swinging type, it does not have to have the configuration as in the above embodiment. The linear actuator 27 using a stack may be used to drive the intake control valves 21 to 24 by replacing the linear movement with a swinging or rotational movement using a rack and pinion mechanism. In this case, since the piezo stack has higher responsiveness, extremely steep opening/closing valve operations can be realized.

In the above embodiment, the swinging speed of the intake control valves 21 to 24 was always driven at a constant speed, but the swinging speed may be changed depending on the situation. For example, as shown in FIG. 12, control may be performed so that there is a stop period (Tb) in the middle of the closing or opening operation.

This stop period (Tb) is adjusted so that, for example, when the rotational speed of the internal combustion engine 1 suddenly changes when the intake control valves 21 to 24 are driven, this stop period (Tb) is adjusted to ensure accurate fully closing timing. It can be used for control such as For example, the actuator 27 is a 4-phase 8-pole actuator configured to be able to stop even at an intermediate valve opening position, and after once stopping at the intermediate position in one control as shown in FIG. ) can be accurately fully closed at a desired position by the process shown in FIG. 8 based on the newly stored CLA value.

In addition, as shown in Fig. 13, the valve closing speed is determined by the internal combustion engine 1.
It may be changed arbitrarily depending on the situation.

For example, when the occurrence of knock is detected from the knock sensor 29c, the intake control valve 2 of the cylinder in which the knock occurs
It is also possible to increase the closing speed of valves 1 to 24 to fully close them earlier (tn) than normal (to), lower the temperature inside the cylinder due to adiabatic expansion of the intake air in the cylinder, and suppress knocking. be.

Similarly, as shown in Figure 14, the intermediate stop period (tb)
may be deleted depending on driving conditions such as knocking.

Further, as shown in the first part, the full opening timing may be controlled depending on the load (in this case, the intake pressure). For example, if the opening degree of the accelerator pedal or throttle valve decreases at medium to low loads, by advancing the timing of full opening, the accelerator depression will be reduced and the intake pressure will be relatively large even at partial loads, resulting in pump loss. This will further contribute to improving torque and fuel efficiency.

Effects of the Invention As detailed above, the intake control device for an internal combustion engine according to the present invention has the following effects.

■Since it operates independently of the rotation of the internal combustion engine, it is not a device that can prevent backflow at a suitable timing, and even if the valve is opened or closed in excess, it will not cause intake air blemishes. Therefore, the backflow prevention effect becomes even more effective, further contributing to improvements in torque and fuel efficiency.

■Since it is not a mechanical adjustment mechanism that transmits and adjusts the rotation of the internal combustion engine as in conventional models, the device has high durability and the intake control valve operates quickly, improving its responsiveness and follow-up. The control accuracy is also high.

[Brief explanation of the drawing]

FIG. 1 is a basic illustration of the present invention, FIG. 2 is a system configuration diagram of an internal combustion engine equipped with an intake control device, FIG. 3 is a longitudinal sectional view showing an intake control valve and an actuator, and FIG. 3 is a sectional view taken along the line BB, FIG. 5 is a sectional view taken along the line AA in FIG. 3, and FIG. 6 is a circuit diagram showing the control system of the actuator.
Figures 7 and 8 are flowcharts showing the control executed by the electronic control unit, Figure 9 is a timing chart showing the state of control when the internal combustion engine is running at high speeds, and Figure 10 is a flowchart showing the control when the internal combustion engine is running at low speeds. 11 is a timing chart showing the state of control; FIG. 11 is a graph showing the relationship between drive current and swing speed of the intake control valve; FIGS. 12 to 14 are timing charts showing other control examples; FIG. The figure shows a timing chart showing the conventional control. Figure 16 (A) is a plan view showing the intake control valve and actuator 27-1,
) is a partially cutaway front view, and (C) is the housing 38-1.
17(A) to (D) are explanatory views of the swinging state of the movable plate, and FIGS. 18(A) to (E) are explanatory views of the coil excitation state of the actuator and the state of the permanent magnet. It is. 1... Internal combustion engine 3... Intake control section 4.
...Electronic control device 5, 6. 7. 8...Cylinder 9.10, 11.12...Intake valve 17.1B, 19. ．． 20...Intake boat 2L 2
2,23,24.21-1.22-1゜23-1.24
-1...Intake control valve 25.25-1...Drive shaft 27.27-1...Actuator 29a...Crank angle sensor 29b...Rotation speed sensor (also serves as rotation angle sensor)
Agent: Patent attorney Tsutomu Sadatsu (and 2 others) Figure 5

Claims (1)

[Scope of Claims] 1. An intake control valve that is disposed in an intake passage communicating with a cylinder of an internal combustion engine and that can open and close the intake passage, and a drive that opens and closes this intake control valve independently of the rotation of the internal combustion engine. means for detecting a rotational position of the internal combustion engine; rotational speed detection means for the internal combustion engine; rotational position data of the internal combustion engine detected by the rotational position detection means; and internal combustion engine rotational position data detected by the rotational speed detection means. a drive control means that sets a timing to prevent backflow of intake air that occurs in the latter half of the opening period of the intake valve based on the rotational speed data of the engine, and causes the drive means to drive the intake control valve to close at this timing; An intake control device for an internal combustion engine, comprising: . 2. The internal combustion engine has a plurality of cylinders, and the drive shaft of the intake control valves arranged corresponding to each cylinder is formed integrally so that all the intake control valves are always driven at the same time, and the drive means 2. The intake control device for an internal combustion engine according to claim 1, comprising an electromagnetic actuator, and capable of driving the intake control valve at a sufficient valve closing speed even when the internal combustion engine is at a maximum rotational speed.