JPH06241096A - Idling speed control device - Google Patents

Abstract

PURPOSE:To provide an idling rotation control device which can enhance the drivability by preventing shock due to irregularity in the generated torque. CONSTITUTION:In an aux. air passage 2 bypassing the first intake throttle valve 1 which is interposed in an intake passage 16, the second intake throttle valve 3 opening and closing in the opposite phase to the first intake throttle valve 1 is interposed in coupling with the first intake throttle valve by a coupling mechanism 31. Because the second intake throttle valve 3 makes opening change in a certain phase difference without response delay to the opening change of the first intake throttle valve 1, shock due to irregularity of the generated torque can be prevented and the drivability be enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an idle speed control device, and more particularly to an idle speed control device for controlling an engine speed during idling of an internal combustion engine.

[0002]

2. Description of the Related Art In an internal combustion engine in which an idle speed control valve (ISCV) consisting of an idle control valve such as a solenoid valve is provided in an auxiliary air passage that bypasses an intake throttle valve such as a throttle valve in the intake passage, this ISCV is used.
The throttle valve is controlled by duty to control the amount of air flowing in the auxiliary air passage by bypassing the throttle valve so that the engine speed during idling matches the target speed.

When an external load is applied to the engine,
For example, when the air conditioner is turned on or the like, in order to prevent engine stall that is likely to occur due to a decrease in engine speed, the ISCV opening is increased and the intake air amount is increased to perform idle up.

[0004]

By the way, when the throttle valve opening exceeds a predetermined value, that is, when the engine is not in the idle operation state, the ISCV opening is controlled to be 0%. As described above, since the ISCV is composed of a duty-controlled solenoid valve,
As shown in (a), for example, a considerably long response delay time t ₁ occurs until the ISCV, which was at the opening α% during the idle operation, becomes 0%, that is, the fully closed state.

Therefore, the intake air amount changes from the intake air amount during idle operation indicated by the straight line A in FIG. 8B to the predetermined intake air amount during non-idle operation indicated by the straight line B in FIG. 8B. A delay time t ₁ similar to the above occurs even when the transition is made.

Then, within this delay time t ₁ ,
As is apparent from FIG. 8B, the intake air amount does not change linearly with the opening of the throttle valve, and therefore the generated torque does not change linearly with the opening of the throttle valve and becomes irregular. As a result, there is a problem that the driver feels a sense of discomfort due to a jerk. The present invention has been made in view of the above points, and improves the drivability by interposing a second intake valve that opens and closes in a phase opposite to the first intake valve in the auxiliary air ventilation path. It is an object of the present invention to provide an idle speed control device capable of achieving the above.

[0007]

FIG. 1 is a block diagram showing the principle of the present invention. As shown in the figure, the present invention relates to a first internal combustion engine.
In an idle speed control device in which an idle control valve 4 is provided in an auxiliary air passage 2 that bypasses the intake throttle valve 1 of
A second intake throttle valve 3 that is connected to the first intake throttle valve 1 and is interposed in the auxiliary air passage 2 and that opens and closes in a phase opposite to the opening and closing of the first intake throttle valve 1 is provided. It is characterized by that.

[0008]

When the vehicle is started after the predetermined warm-up control is completed, or when the predetermined warm-up control is stopped midway and the vehicle is started by performing the returning operation, the first intake throttle valve 1 interposed in the intake passage is The valve is opened to a predetermined opening degree from the fully closed state where the opening degree is 0%. In this case, the second intake throttle valve, which is connected to the first intake throttle valve in a predetermined reverse phase by the connecting means and is interposed in the auxiliary air passage that bypasses the first intake throttle valve, First
The opening degree of the intake throttle valve is changed with a predetermined reverse phase difference without a response to the opening degree change of the intake throttle valve, and the auxiliary air passage is shut off. Therefore,
Since the generated torque is not irregular, the shock due to the irregular torque can be prevented and the drivability is improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an idle speed control device for an internal combustion engine will be described below. FIG. 2 is a configuration diagram showing the configuration of the internal combustion engine and its peripheral devices according to the present embodiment. In FIG. 2, the same components as those in FIG. 1 are designated by the same reference numerals.

In FIG. 2, 5 is an engine body, 6 is a piston, and 7 is
Is a cylinder, 8 is a spark plug, 9 is an intake valve, 10
Is an exhaust valve, 11 is an exhaust manifold, 12 is an oxygen sensor for detecting the oxygen concentration in the exhaust gas, and 13 is a water temperature sensor for detecting the engine cooling water temperature.

In the intake system, in the figure, 14 is an air cleaner, 15 is an air flow meter for measuring the amount of intake air,
1 is a first throttle valve corresponding to the first intake throttle valve in FIG. 1 installed in the intake passage 16, 2 is an auxiliary air passage bypassing the throttle valve 1, and 3 is an auxiliary air passage 2. Corresponding to the second intake throttle valve in FIG.
Throttle valve, 31 is the first throttle valve 1
A connecting mechanism 4 for connecting the second throttle valve 3 and the second throttle valve 3 is interposed in the auxiliary air passage 2 on the downstream side of the second throttle valve 3, and a pulse with a predetermined duty ratio is instructed by the controller 20. An idle speed control valve (ISCV) 17 corresponding to the idle control valve of FIG. 1, whose opening is controlled by a signal, is a first
A throttle position sensor that outputs a signal corresponding to the opening of the throttle valve 1, 18 is an intake manifold,
Reference numeral 19 is a fuel injection valve, and 21 is an intake air temperature sensor for detecting the temperature of intake air.

Here, the first throttle valve 1,
The second throttle valve 3 and the connecting mechanism 31 will be described with reference to FIGS. 3 and 4.

As shown in FIG. 3, one end side (left side in the figure) of the rotary shaft 1a of the first throttle valve 1 inserted in the intake passage 16 is fixed to the fixing member 1 via a spring 1b.
It is fixed to c and is connected to an accelerator pedal 32 via an accelerator wire 31.

Further, one end side (the left side in the figure) of the rotary shaft 3a of the second throttle valve 3 interposed in the auxiliary air passage 2.
Is connected to the other end of the rotary shaft 1a of the first throttle valve 1 via a one-way clutch 33, and is fixed to a fixing member 3c via a spring 3b. The other end of the rotary shaft 3a is connected to an actuator 35 via a one-way clutch 34. This actuator 35 is
For example, when the idle speed control valve 4 fails in the fully opened state, it has a role of holding the second throttle valve 3 in the fully closed state.

The one-way clutches 33 and 34 constitute a connecting mechanism 31, and the second throttle valve 3 is connected to the first throttle valve 1 by the connecting mechanism 31, and the first throttle valve 3 is connected. It operates so that there is no response delay to the operation of 1.

The second throttle valve 3 has a predetermined antiphase with respect to the first throttle valve 1 on the rotary shaft 3a, for example, an antiphase of 90 ° as shown in FIG. 4A or FIG. 4B. As shown in FIG. 5, the rotary shaft 3a is mounted in the opposite phase of 45 °, and the rotary shaft 3a is arranged such that the axis of the rotary shaft 3a coincides with the axis of the rotary shaft 1a.

Therefore, the second throttle valve 3 has 90
When the first throttle valve 1 is fully opened, it is attached to the rotating shaft 3a in the opposite phase of 0 ° and is connected to the first throttle valve 1 through the connecting mechanism 31. 2), the second throttle valve 3 is fully closed, while the second throttle valve 3 is fully open when the first throttle valve 1 is fully closed.

When the second throttle valve 3 is in the fully closed state, as shown in FIG.
A slight gap ε is formed between the throttle valve 3 and the inner wall of the auxiliary air passage 2.

Further, the second throttle valve 3 is 45 °
4 (b) when the first throttle valve 1 is fully closed while being attached to the rotary shaft 3a in the opposite phase to the first throttle valve 1 through the connecting mechanism 31. ), The second throttle valve 3 has an opening of 50%, while the second throttle valve 3 is fully closed when the first throttle valve 1 has an opening of 50%.

When the second throttle valve 3 is fully closed, a slight gap ε is formed between the second throttle valve 3 and the inner wall of the auxiliary air passage 2 as described above. To be formed.

Next, in the ignition system, 2 in FIG.
Reference numeral 3 denotes an igniter that outputs a high voltage required for ignition from the secondary side of the ignition coil, 24 denotes a distributor that supplies a high voltage generated by the igniter 23 to the ignition plugs 8 of each cylinder, which is interlocked with a crankshaft (not shown), and 25. Is a rotation angle sensor that outputs a pulse signal 24 times per revolution of the distributor 24 (two revolutions of the crankshaft), and 26 is a cylinder discrimination sensor that outputs a pulse signal once per revolution of the distributor 24. The control device 20 is composed of a micro controller, and inputs signals from various sensors and performs predetermined arithmetic / control based on these input signals to output predetermined signals to various actuators.

Next, FIG. 5 shows specific components of the controller 20.

A central processing unit (CPU) 40 inputs and calculates data output from each sensor in accordance with a control program, and also performs processing for controlling various actuators such as the fuel injection valve 19, ISCV 4, igniter 23 and the like. It has become. Read-only memory (R
The OM) 41 is a storage device for storing data such as the control program and operation map, and the random access memory (RAM) 42 temporarily reads and writes data output from each sensor and data necessary for operation control. The backup random access memory (backup RAM) 43 is a storage device that backs up data and the like necessary for driving the engine by a battery power source even when an ignition switch (not shown) is turned off.

The input section 44 also shapes the output signals of the sensors such as the oxygen sensor 12 and the intake air temperature sensor 21 by a waveform shaping circuit (not shown) and selectively outputs the signals to the CPU 40 by a multiplexer (not shown). ing. In the input unit 44, if the output signal from each sensor is an analog signal, this is converted into a digital signal by an A / D converter. The input / output unit 45 is the rotation angle sensor 2
5. The output signal of the cylinder discrimination sensor 26 or the like is shaped by the waveform shaping circuit, and this signal is RAM-transmitted through the input port.
42 and so on. Further, the input / output unit 45 drives the fuel injection valve 19, the igniter 23, the ISCV 4 and the like at a predetermined timing by a drive circuit driven via the output port according to a command from the CPU 40. The bus line 46 is the CP
The U40, the ROM 41, and other elements and the input section 44 and the input / output section 45 are connected to send various data.

The control device 20 calculates the fuel injection amount and the like according to the operating conditions based on the detection data input from each sensor, and at the time of idling, the valve opening to be output to the ISCV 4 according to the operating state. By calculating the pulse duty ratio and outputting this calculation signal to the ISCV 4, the idle speed is controlled to the target speed.

Next, the operation of the above embodiment will be described.
For example, when the second throttle valve 3 is attached to the first throttle valve 1 in the opposite phase of α °, the idle operation state, that is, when the opening of the first throttle valve 1 is 0%, the first throttle valve 3 is opened. When the valve 1 is in the fully closed state, the ISCV 4 is in the fully open state at an opening of 100%, and the second throttle valve 3 is in the open state at an opening corresponding to the antiphase difference α °.

Therefore, a predetermined amount of intake air flows into the intake manifold 18 via the auxiliary air passage 2, the second throttle valve 3, the ISCV 4, etc., and the controller 20
Predetermined warm-up control is performed by.

On the other hand, when the vehicle is started after the completion of the predetermined warm-up control or when the predetermined warm-up control is stopped midway and the vehicle is started by performing the return operation, the first line A in FIG. The throttle valve 1 is opened from a fully closed state with an opening of 0% at a predetermined opening corresponding to the depression amount of the accelerator pedal 32.

In this case, since the second throttle valve 3 is connected to the first throttle valve 1 by the connecting mechanism 31, the second throttle valve 3 operates without a response delay with respect to the operation of the first throttle valve 1. As indicated by a straight line B in 6, the first throttle valve 1 is in the opposite phase to the first throttle valve 1 until the opening T% corresponding to the opposite phase difference α °, that is, the first throttle valve 1 is opened. When the throttle valve 1 operates in the direction of increasing the opening, the second throttle valve 3 operates in the direction of decreasing the opening. Then, when the first throttle valve 1 becomes the opening degree T% corresponding to the anti-phase difference α ° from the opening degree 0%, the second throttle valve is fully closed, and thereafter the first throttle valve 1 The second throttle valve 3 is maintained in the fully closed state even when is greater than the opening T%. Therefore, when the vehicle starts after the predetermined warm-up control is completed, or when the predetermined warm-up control is stopped midway and the vehicle is started by performing the return operation, the reverse phase difference is, for example, 45 °, and As shown by the straight line A, when the opening degree of the first throttle valve 1 increases from 0% to 50%, for example, the opening degree of the second throttle valve 3 corresponding to the phase difference of 45 ° without a response delay from this increase. 0% opening from T _B
And the auxiliary air passage 2 is cut off. As a result, the intake air amount shifts from the intake air amount during the idle operation indicated by the straight line A in FIG. 7B to the predetermined intake air amount during the idle operation state indicated by the straight line B in FIG. 7B. The time t ₂ required for this is extremely short as compared with the considerably long response time t ₂ (see FIG. 8) already described in the “Prior Art” section. The time axis (horizontal axis) in FIGS. 7 and 8 is represented by the same scale.

According to the above embodiment, the first throttle valve 1 provided in the intake passage 16 and the second throttle valve 3 provided in the auxiliary air passage 2 are connected in opposite phases to open and close. Therefore, even if the ISCV 4 has a considerably long response delay time, the second throttle valve 3 can close the auxiliary air passage 2 in a very short time.

Therefore, the first throttle valve 1 is operated from the idle operation state, that is, the state in which the auxiliary air passage 2 is in conduction.
When shutting off the auxiliary air passage 2 according to the opening degree of
It is possible to prevent a shock due to irregularity of generated torque, and as a result, it is possible to improve drivability.

Further, the second throttle valve 3 has an opening of 0.
When the valve is fully closed at%, a slight gap ε is formed between the second throttle valve 3 and the inner wall of the auxiliary air passage 2. The idle speed control valve 4 is formed by forming this gap portion ε.
When the second throttle valve 3 is fully closed, the intake air flows into the intake manifold 18 side through the interval portion ε when the valve fails in the full open state. Therefore, it is possible to prevent the engine speed from decreasing. Therefore, engine stall can be prevented.

In the above, the second throttle valve 3
Is not limited to the case where the auxiliary air passage 2 is provided on the upstream side of the ISCV 4 as in the above-described embodiment.
It may be provided on the downstream side of the SCV 4.

Further, the idle speed control valve 4 is not limited to a valve whose opening degree is controlled to be turned on / off by a pulse signal with a predetermined duty ratio, but is, for example, a solenoid valve having different responsiveness. May be.

The connecting mechanism 31 is not limited to the one-way clutches 33 and 34, but may be a gear or the like.

[0036]

According to the present invention, the second intake throttle valve, which is connected to the first intake throttle valve interposed in the intake passage and is opened / closed in a phase opposite to that of the first intake throttle valve, is provided. Is interposed in the auxiliary air passage that bypasses the first intake throttle valve, so that the opening degree of the second intake throttle valve is reversed without a response delay in response to the opening degree variation of the first intake throttle valve. Since the opening degree fluctuates to a predetermined opening degree, it is possible to prevent a shock due to the irregularity of the generated torque, and thus to improve drivability.

[Brief description of drawings]

FIG. 1 is a principle configuration diagram of the present invention.

FIG. 2 is a configuration diagram showing a configuration of an internal combustion engine and its peripheral devices according to an embodiment of the present invention.

FIG. 3 is a view showing a connection mechanism of an example of a first throttle valve and a second throttle valve.

FIG. 4 is an explanatory diagram for explaining phase states of a first throttle valve and a second throttle valve.

FIG. 5 is a diagram showing a specific configuration of a control device.

FIG. 6 is a diagram showing a relationship between a depression amount of an accelerator pedal and an opening degree of a first throttle valve and an opening degree of a second throttle valve.

FIG. 7 is a diagram showing changes in opening and intake air amount of each of a first throttle valve and a second throttle valve.

FIG. 8 is a diagram for solving a conventional problem.

[Explanation of symbols]

 1 First intake throttle valve (first throttle valve) 2 Auxiliary air passage 3 Second intake throttle valve (second throttle valve) 4 Idle control valve (ISCV) 5 Engine body 16 Intake passage 18 Intake manifold 20 Control Device 31 Connection mechanism

Claims (1)

[Claims] 1. An idle speed control device in which an idle control valve is provided in an auxiliary air passage that bypasses a first intake throttle valve of an internal combustion engine, wherein the auxiliary air passage is connected to the first intake throttle valve. An idle speed control device, characterized in that a second intake throttle valve, which is provided inside and is opened and closed in a phase opposite to that of the opening and closing of the first intake throttle valve, is provided.