JPS60173338A - Output controller of internal-combustion engine - Google Patents

Abstract

PURPOSE:To enlarge the margin to which control can be performed by controlling a supplementary air quantity control valve at the time of steady run other than idling so as to maintain the execution sectional area of a supplementary air passage to be a preset value. CONSTITUTION:A supplementary air quantity control valve is disposed in a supplementary air passage which bypasses a throttle valve. The means for detecting the state of steady run other than idling is provided and when the means detects that an engine state is of steady run other than idling, the means maintains the execution sectional area of the supplementary air passage to be a preset value. When output control is performed using the supplementary air control valve at the time of transient operation, ample margin to which the control can be performed can be provided with respect to any case where the output is increased or decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a device for controlling the output of an internal combustion engine, and more particularly to an improvement in an output control device using an auxiliary air amount control valve for controlling the idle speed.

BACKGROUND ART Conventionally, there is a device shown in FIG. 1 as a device for controlling the rotational speed of an internal combustion engine during idling.

In the figure, a throttle valve 2A is installed in the intake pipe 1 of the engine.
. A negative pressure controlled by a VCM valve (negative pressure control solenoid valve) 5, which will be described later, is introduced into a pressure working chamber 4b defined by a diaphragm 4a, and the AAC pulp 4 is connected to the diaphragm 4a according to the negative pressure. The idle speed is controlled by controlling the amount of auxiliary air flowing into the auxiliary air passage 3 by changing the opening degree of the valve body 4c.

The 70M valve 5 is a diaphragm type constant pressure valve that controls the manifold negative pressure downstream of the throttle valves 2A and 2B at a constant level, and two solenoid valves that control the negative pressure supplied to the AAC valve 4 and the EGR control valve (not shown). It's made up of a lot of things. That is, the diaphragm 5a
A manifold negative pressure is introduced into the negative pressure chamber 5b defined by The negative pressure chamber 5 is closed by closing the open end of the introduction pipe 5c.
The negative pressure inside b is maintained at the predetermined value. The atmospheric pressure chamber 5e communicates with the negative pressure chamber 5b via the orifice 5d and communicates with the intake pipe upstream of the throttle valves 2A and 2B via the atmospheric air introduction pipe 6, and the solenoid pulp 5f allows free control of communication and interruption. A negative pressure outlet 5g is connected to the pressure operating chamber 4b of the AAC valve 4.

By controlling the valve opening duty (t) of the solenoid pulp 5f according to the output from the control unit 7, the negative pressure led from the negative pressure chamber 5b of the V C, M valve 5 is introduced from the atmospheric pressure chamber 5e. The negative pressure introduced into the pressure operating chamber 4b of the AAC valve 4 is controlled by changing the rate of pressure reduction depending on the atmosphere.

By the way, in such an idle speed control device,
Conventionally, during idling operation, a target rotation speed is set in advance according to engine operating conditions such as cooling water temperature.On the other hand, a solenoid pulp is used to detect the actual engine rotation speed and bring this actual rotation speed closer to the target rotation speed. Feedback control is performed to control the duty ratio (A) of the pulse signal supplied to 5f.

On the other hand, during operation other than idling, a constant value is obtained by adding the set value of the duty ratio that depends on the engine speed to the duty ratio of the pulse signal supplied to the solenoid pulp 5f immediately before switching from the idling operation to another operating state. Oven loop control is performed using as the control value.

However, in such a control method during operation other than idling, torque fluctuations are suppressed by increasing or decreasing the engine output at the time of shift change of an automatic transmission, as shown in Japanese Patent Laid-Open No. 58-077138, for example. When attempting to accelerate or decelerate rapidly,
Even if you attempt to control the output by changing the opening degree of the AAC pulp, the opening degree of the AAC pulp immediately before the control is set according to the operating state at that time, so there is no margin for control and sufficient control cannot be performed. There were cases where there was none.

<Purpose of the Invention> The present invention has been made in view of the problems of the conventional art, and provides a method for controlling output to either increase or decrease using an auxiliary air flow control valve in a steady state of operation other than idling. However, it is an object of the present invention to provide an output control device for an internal combustion engine that can perform good control with sufficient margin.

<Summary of the Invention> Therefore, as shown in FIG. 2, the present invention provides an auxiliary air amount control valve in an auxiliary air passage that bypasses a throttle valve, and controls the opening degree of the auxiliary air amount control valve. In an output control device for an internal combustion engine that adjusts engine output by controlling the amount of auxiliary air, there is provided a means for detecting a steady state of operation other than idling, and a means for detecting a steady state of operation other than idling detected by the detection means. The structure includes means for controlling the auxiliary air amount control valve in such a manner that the effective cross-sectional area of the auxiliary air passage is maintained at a predetermined value.

<Example> The present invention will be described in detail below. FIG. 3 shows the configuration of one embodiment, and components other than the internal configuration of the control unit 11 are designated by the same reference numerals as those of the conventional example shown in FIG. 1, and the explanation thereof will be omitted. Also, a crank angle sensor 12 for detecting rotation speed, a water temperature sensor 13 for detecting cooling water temperature, a throttle valve switch 14 for detecting fully closed throttle valve, an air conditioner switch 15, a vehicle speed sensor for detecting vehicle speed, and a transmission neutral. Signals and the like from the neutral relay switch 16 for position detection are input to the control unit 11.

Control unit 11 consists of a microcomputer, etc., and determines the engine operating state according to signals from the various sensors, and under predetermined idle operating conditions, sets the actual rotation speed according to water temperature, etc., as in the past. The opening degree of the AAC valve 4 is controlled by feedback control of the valve opening duty of the solenoid pulp 5f of the VCM valve 5 so as to match the target rotation speed. However, when a steady operating state other than idle is detected, the solenoid pulp 5f The opening duty of the AAC valve 4 is controlled to 50% to maintain the opening degree of the AAC valve 4 at the fully open position. That is, the effective cross-sectional area of the auxiliary air passage is controlled to a predetermined value (50% in this case). Further, during acceleration/deceleration operation from the steady operating state, the valve opening duty to the solenoid pulp 5f is increased or decreased from 50% in the steady operating state to increase or decrease the AAC pulp opening.

Next, the above control by the control unit 11 is carried out in a fourth manner.
The explanation will be given according to the flowchart shown in the figure.

At S1, it is determined whether or not it is a steady operating state other than idle, and if YES, the process advances to S2 and the valve opening (ISOON) duty of the solenoid pulp 5f is set to 50%.

The determination of a predetermined operating state other than the idle state is performed, for example, in the fifth
It is done as shown in the figure. That is, in sia it is determined whether the idle contact of the throttle valve switch is OFF or not, and in S1b it is determined whether the vehicle speed is 8 km/h or more, and when both of these determinations are YES, the It is determined that the engine is in a steady idle operating state.

Then, in S11, a pulse with the valve opening duty of 50% is output to the solenoid pulp 5f, whereby the negative pressure in the pressure operating chamber 4b of the AAC valve 4 becomes the center value of the control range, and the opening duty with respect to the valve body 4 becomes The degree is controlled to approximately A, which is fully open.

If the determination in Sl is NO, the process proceeds to S3, where a target rotation speed for performing idle rotation speed control is set.

The target rotation speed in this case is set mainly based on the cooling water temperature. Next, proceed to S4, and based on the cooling water temperature
While calculating the basic value l5OTW of ON duty,
After calculating the correction value 15CAT% depending on whether or not the air conditioner is used, the gear position of the autotransmission, the correction value 15CA8 after starting, etc., the process proceeds to S5.

S5 detects the battery voltage, and if the voltage is low,
The target rotation speed set in S3 is corrected to increase and the process proceeds to S6.

In S6, it is determined whether or not to perform feedback control of the 15OQN duty based on the actual measured value of the engine speed. For example, if the idle contact of the throttle valve switch 14 is ON and the gear position of the transmission is neutral, or if the vehicle speed is 8 Km/h or less, and the actual rotation speed and target Feedback control is performed in a so-called idling state, such as when the difference from the rotational speed is greater than a predetermined value.

When the determination in S6 is YES, the actual rotation speed is compared with the target rotation speed in S7, and l5OO is set so as to approach the target rotation speed.
A feedback correction value l5OFB for increasing/decreasing the N duty ratio is calculated, and the process proceeds to S8.

In S8, each value obtained in S4 l5OTW, ISC person T, l5
Add the l5CFB obtained in CA8 and S7 to get the final l
After the 5OON duty, a pulse having the 15CoN duty is outputted to the solenoid pulp 5f at the Sll, and the opening degree of the AAC pulp 4 is feedback-controlled.

Further, if the determination in S6 is NO, it means either acceleration operation or deceleration operation, and after making this determination, the correction value l5CRT for acceleration/deceleration is set. Specifically l5O)IT
is a positive value when accelerating and a negative value when decelerating. And S10
Proceed to the previous ISCO and set the l5CON duty value to
It is updated as a value obtained by adding the above-mentioned 15CRT to the N duty, and in step 811, a pulse having a 15CON duty is output to the solenoid pulp 5f.

In this case, at the time of starting, acceleration correction is performed on the value calculated in S8 as in the conventional case, but other than that, acceleration/deceleration is performed from a steady operating state other than idling, and in this case,
l5OON duty value 50 fixed in S2
Since acceleration/deceleration correction is performed by increasing or decreasing the duty using % as the initial value, it is possible to have sufficient margin in the control amount for increasing or decreasing the duty for both acceleration and deceleration, ensuring good acceleration and deceleration performance at all times. It is possible.

Incidentally, the acceleration correction other than the start in S9 may be performed, for example, in the case of temporarily accelerating during a downshift operation of the transmission to smooth the engagement of the clutch, as shown in the above-mentioned Japanese Patent Application Laid-Open No. 58-77138. etc.

FIG. 6 shows a second embodiment, and is a flowchart in which the l5OON duty is not immediately set to 50% after transition to a steady operating state other than idling, but is gradually set to 50%.

The control during other operations is the same as that shown in FIG. 4 from 83 to Sll, so the explanation will be omitted.

In the figure, the ISC'ON duty is 50 in S21.
Determine whether it is less than %, and if YES, proceed to S22
Proceed to and increase the l5CON duty by 1. Then, in 823, it is determined whether the value of l5CON duty is 50%, and if YES, the process advances to S24 and l5OON
After fixing the duty at 50, it is output to the solenoid valve 5f at 828, and if NO, the value added at S22 is output as is at ts28.

On the other hand, if the determination in 821 is No, in S25, l5O
The ON duty is decreased by one factor, and in S26 it is determined whether the l5OON duty is 49% or not. If YES, the l5CON duty is fixed at 50 factors and output in S28, and if NO, in S25. The calculated value is output as 328.

If the 15OON duty is gradually changed to 50 in this way, the change in the opening degree of the AAC valve will be gradual when transitioning to steady operation other than idling, and the shock caused by the output change can be alleviated.

In addition to the negative pressure control type shown in the embodiment, the auxiliary air flow control valve may also be used by sending pulse signals to the valve opening coil and valve closing coil in an inverted state, and adjusting the duty ratio of the pulse signal. It goes without saying that the present invention can also be applied to a device in which the opening degree or the duty ratio of the valve opening time is adjusted in accordance with the above, thereby controlling the effective cross-sectional area of the auxiliary air passage to a predetermined value.

<Effects of the Invention> As explained above, according to the present invention, in a steady state of operation other than idling, the auxiliary air amount control valve is controlled to maintain the effective cross-sectional area of the auxiliary air passage at a predetermined value. Therefore, when performing output control using the auxiliary air flow control valve during transient operation, there is sufficient control margin for both increases and decreases in output, thereby ensuring good output control at all times. This gives you the advantage of being able to.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a conventional idle speed control device, FIG. 2 is a block diagram showing the structure of the present invention, FIG. 3 is a block diagram showing a first embodiment of the present invention, and FIG. This figure is a flowchart of the same embodiment as above, FIG. 5 is a flowchart showing a specific example of a part of the judgment conditions of the above flowchart, and FIG. 6 is a flowchart of a second embodiment of the present invention. 1...1lti path 2A, 2B...throttle valve 3...auxiliary air passage 4...AAC valve 5.
・・70M pulp 11・・Control unit
12...Crank angle sensor 13...Water temperature sensor
14...Throttle valve switch 15...Air conditioner switch 16...Neutral relay switch Patent applicant Fujio Sasashima, patent attorney representing Nissan Motor Co., Ltd.

Claims (1)

[Claims] An output of an internal combustion engine that is equipped with an auxiliary air amount control valve in an auxiliary air passage that bypasses a throttle valve, and adjusts the engine output by controlling the amount of auxiliary air by controlling the opening degree of the auxiliary air amount control valve. The control device includes means for detecting a steady operating state other than idling, and controlling an auxiliary air amount control valve in a steady operating state other than idling detected by the detecting means, and controlling an effective cross-sectional area of the auxiliary air passage. 1. An output control device for an internal combustion engine, comprising means for controlling the output to maintain the output at a predetermined value.