JPH0361646A - Engine speed controller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine rotation speed control device, and particularly to a device that detects an idle state from a throttle opening value and performs idle control.

[Conventional technology]

Conventional engine speed control devices determine the idle state when the vehicle is stopped and the idle switch is on (the throttle valve is closed), and perform closed loop control, and when the vehicle is running or the idle switch is off. When the engine is in a non-idling state, it is determined that the engine is in a non-idling state, and open-loop control is performed to control the engine speed by controlling the amount of air supplied to the engine.

The above-described oven loop control is to maintain a constant opening degree of an air control valve provided in a bypass conduit that bypasses the throttle valve of the engine.

The closed-loop control described above determines the target rotation speed and basic air amount based on the operating state of the engine, such as whether an electric load is applied, whether the automatic transmission is in the neutral range or drive range, and the engine cooling water temperature. A feedback correction amount that eliminates the deviation between the target rotation speed and the actual rotation speed is determined by learning, and the opening degree of the air control valve is controlled using the sum of the basic air amount and the feedback correction amount as the control amount. It is.

Note that since the amount of fuel supplied to the engine is determined according to the amount of air supplied, the actual rotation speed can be controlled by controlling the amount of air supplied.

[Problem to be solved by the invention]

The conventional engine speed control device is as described above.
Actually, in order to use an inexpensive idle switch built into the throttle opening sensor, the relationship between the actual throttle opening value θ and the actual rotational speed Ne is shown in Figure 4, which shows the true value when the throttle valve is fully closed. When the idle opening value of is θIIIL, the idle switch is turned on when θIIIL≦θ≦θIDL+β, the idle state is determined, and closed loop control is performed.

Therefore, even when the accelerator pedal is depressed slightly and the throttle valve is slightly open, the actual throttle opening value θ may be close to θIDL+β and the idle switch may be on. If closed-loop control is performed in this state, the closed-loop control limit will be exceeded, the actual rotational speed will greatly exceed the target rotational speed, and the air control valve will be almost fully closed. After that, when the driver takes his foot off the accelerator pedal, the throttle valve is fully closed, but since the air control valve is closed too much, the actual rotation speed decreases due to closed-loop control, which opens the air control valve to a certain degree. The responsiveness that opens up will be faster. As a result, there have been problems such as the actual rotation speed being significantly lower than the target rotation speed, the vibration of the vehicle body caused by this decrease, and in the worst case, the engine stalling.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to prevent an unnecessary drop in the actual rotational speed even if the throttle valve opening changes within the throttle opening range in the idling state. The purpose is to obtain an engine speed control device.

[Means to solve the problem]

The engine speed control device of the present invention includes means for detecting an idle state and a control means for performing idle control, wherein the detecting means detects when the throttle valve is within a predetermined opening range from fully closed. The idle state is detected by detecting that the switch means is in a predetermined state and the throttle valve is in a predetermined opening range narrower than the predetermined opening range.

[For production]

In the engine rotation speed control device of the present invention, since the throttle opening range in which the detection means detects the idle state is within the idle control range, even if the opening range changes, the actual rotation speed is changed to the target rotation speed. can be converged with good responsiveness.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a configuration diagram showing an engine rotation speed control device etc. according to an embodiment of the present invention. In the same figure, ■ is an engine installed in, for example, a car, which inhales main air through an air cleaner 2, an intake pipe 3, and an intake branch pipe 4, and the fuel is a single electromagnetic fuel installed in the intake pipe 3. It is injected and supplied from the injection valve 5.

This amount of fuel is determined by a fuel control system (not shown), for example, based on an output signal of a pressure sensor 6 that detects the pressure inside the intake pipe 3 in absolute pressure.

7 is a throttle valve that adjusts the main intake air amount of the engine l by arbitrary operation of the accelerator pedal (not shown) by the driver; 8 is a throttle opening sensor that detects the opening of the throttle valve 7; 9 is a throttle valve This is an idle switch that detects when throttle valve 7 is almost closed.If the idle opening value when throttle valve 7 is fully closed is θIDL, it turns on when the actual throttle opening value θ is less than or equal to θIOL+β, where β is a positive value. .

10 is a bypass conduit provided to bypass the throttle valve 7 on the downstream side of the electromagnetic fuel injection valve 5, and 11 is an air control valve provided between the bypass conduits 10. One end of the bypass conduit 10 is connected to an air inlet provided between the electromagnetic fuel injection valve 5 and the throttle valve 7, and
The other end of the bypass conduit 10 is connected to an air outlet provided downstream of the throttle valve 7.

The air control valve 11 has an opening degree that corresponds to, for example, the duty ratio of the applied drive signal! A burst Yanai is used to control the flow cross-sectional area of the bypass conduit lO in proportion to its duty ratio.

The ignition device of the engine 1 is connected to an ignition control system that forms an ignition signal from operating state parameters of the engine 1, and an igniter 13 and an ignition coil that control on/off the primary current of the ignition coil 12 according to this ignition signal. 12,
It consists of a distributor (not shown), a spark plug (not shown), and the like.

Reference numeral 14 represents the temperature of the engine 1, for example, a cooling water temperature sensor that detects the cooling water temperature; 15, an electric load switch for turning on the load of auxiliary equipment such as an air conditioner; and 16, a torque converter signal for the automatic transmission. A signal line 17 is a vehicle speed sensor that outputs a pulse signal with a frequency proportional to the rotational speed of the axle and detects the vehicle speed. 18 is an exhaust pipe of engine l, and 19 is a catalyst, in which the air-fuel mixture combusted by engine l is purified as exhaust gas and discharged to the outside.

Reference numeral 20 denotes an electronic control unit that is operated by being supplied with power from a battery 21 via a key switch 22, and includes an idle switch 9, a throttle opening sensor 8, and a vehicle speed sensor 17.
The ignition signal on the primary side of the ignition coil 12 is determined according to the result of this determination based on the output signal from the ignition coil 12.
Signal from cooling water temperature sensor 14, electrical load switch 15
The air control valve 11 is driven and controlled based on the signal from the signal line 16 to determine the control amount during closed loop control of the air control valve 11 or to determine the control amount during open loop control.

Next, the electronic control unit 20 will be explained with reference to FIG. 100 is a microcomputer, a CP that calculates the control amount of idle rotation, etc. according to a predetermined program.
U200, a free running counter 201 for measuring the rotation period of the engine 1, a timer 202 for measuring the duty ratio of the drive signal applied to the air control valve 11;
An A/D converter 203 that converts analog input signals into digital signals, an input port 204 that inputs digital signals as they are, a RAM 205 that serves as a work memory, and a ROM that stores programs such as the flow shown in Figure 3.
206, output port 207 for outputting a drive signal;
It is composed of a common bus 208 and the like. 101 is the first
A human interface circuit shapes the waveform of the primary side ignition signal of the ignition coil 12 and outputs it to the micro combinator 100 as an interrupt signal. When this interrupt signal is generated, the CPU 200 reads the value of the counter 201, calculates the cycle of the engine rotation speed from the difference from the previous value, and stores it in the RAM 201.
Store in 5. [02 is a second human power interface circuit, which removes noise components from the output signals of the throttle opening sensor 8 and the cooling water temperature sensor 14, and outputs them to the A/D converter 203. Reference numeral 103 denotes a third human power interface circuit, which outputs the on signal of the idle switch 9, the on signal of the electric load switch 15, the neutral safety signal from the signal line 16, and the pulse from the vehicle speed sensor 17 to a predetermined level to the input port 204. do.

104 is an output interface circuit, and output port 207
The drive signal from the air control valve 11 is amplified and outputted to the air control valve 11. A first power supply circuit 105 converts the voltage of the battery 21 into a constant voltage and supplies it to the microcomputer 100 when the key switch 22 is turned on.

A second power supply circuit 106 supplies power from the battery 21 to the RAM 203 regardless of whether the key switch 22 is on or off, making the RAM 205 nonvolatile.

Next, the operation of this embodiment will be explained with reference mainly to FIG. 3 among FIGS. 1 to 3. First, in step S1, it is determined whether a pulse is generated from the vehicle speed sensor 17, that is, whether the vehicle is stopped. If the vehicle is stopped, the process proceeds to step S2, where it is determined whether the idle switch 9 is on, that is, whether the throttle valve 7 is almost closed.

If it is on, the process advances to step S3, where the actual throttle opening value θ of the throttle valve 7 is read from the throttle opening sensor 8 via the second manual ink face circuit 102 and the A/D converter 203. It is determined whether the actual throttle opening value θ is the minimum value θ5hin, and the minimum value θmi is determined.
If not, the process proceeds to step S6, and if the minimum value θsin, the process proceeds to step S5, where this actual throttle opening value θ is set as the idle opening value θIII when the throttle valve 7 is fully closed.
θIDL, that is, the minimum value θwin is updated, and the process proceeds to step S6.

In step S6, it is determined whether the actual throttle opening value θ is less than or equal to the throttle opening value for idle determination oIDL+α (where 1α is the throttle opening correction value for idle determination, and 0<α<β holds). do.

If it is below, the opening degree of the air control valve 11 is controlled within the limit of closed loop control, that is, the air control valve 11 is not nearly fully closed, so in step S7, a well-known closed loop control is performed using the actual rotation speed Ne. During this closed loop control, the actual rotational speed Ne obtained from each signal of the cooling water temperature sensor 14, the electric load switch 15, the signal line 16, and the period of the ignition signal from the ignition coil 12 is used.

On the other hand, if it is determined in step S1 that the vehicle speed sensor 17 is generating a pulse and the vehicle is not stopped, step S2
If it is determined that the idle switch 9 is off in step S6, the actual throttle opening value θ is larger than the idle determination throttle opening value θIDL+α, that is, exceeds the closed loop control limit, and the air control valve 11 is turned off. If either of the cases is determined to be almost fully closed, the process advances to step S8. In step S8, well-known oven loop control is performed to control the air control valve 11 to a predetermined opening degree.

After the processing in step S7 or step 8, the process returns, and after returning, the process returns to step Sl to repeat the above operation.

FIG. 4 is a diagram showing changes in the actual rotational speed Ne (vertical axis) and the idle switch 9 with respect to the actual throttle opening value θ (horizontal axis). When the actual throttle opening value θ is equal to the true idle opening value θIDL when the throttle valve 7 is fully closed, the actual rotational speed Ne becomes Ne1, for example, 800 rp-, and the actual throttle opening value θ is the limit for turning on the idle switch 90. When θ1゜L+β, the actual rotational speed Ne is Nag, for example 1200
rpm, 0 in this example, θ, 1≦θ≦θl1lL+
The closed-loop control is performed by determining that the vehicle is in an idling state when α and the vehicle is determined to be stopped, and the closed-loop control is effective within this throttle opening value range.

Note that in the above embodiment, the second tiff1 circuit 106
is not particularly necessary, and the RAM 205 may be a volatile memory.

FIG. 5 shows the flow of idle opening determination processing according to another embodiment of the present invention. This flow diagram is the third
The processes of steps 53 to S5 in the figure are executed separately from the idle rotation speed control process. In FIG. 5, the same processing as in FIG. 3 is given the same symbol. In addition, the idle rotation speed control process is the same as in FIG. 3, by removing steps 33 to S5 and connecting the affirmative determination in step S2 and step S6. The idle rotation speed control process is performed after the process shown in FIG. 5 is executed, but its explanation will be omitted. In FIG. 5, first in step SIO it is determined whether or not the idle switch 9 is on, and if it is on, steps S3 to S4 or step 5
The process moves to steps 3 to s5, and if it is not on but off, the process returns. If it is determined in step S4 that θ is not θsin, or after the processing in step S5, the process returns. Note that the processing in steps 53 to S5 has already been explained with reference to FIG. 3, so the explanation thereof will be omitted. After returning, the idle speed control process is executed, and then the process returns to step 310 to repeat the above operation. In this second embodiment, θ detected in step S3 in FIG. 5 is used in step s6, but In FIG. 3, step S3 may be connected to step S6 without being removed.

In this case, the processing method shown in FIG. 5 is the same as in the above embodiment.

〔Effect of the invention〕

As described above, according to the present invention, the opening range of the throttle valve in the idling state is configured to be within the range in which closed loop 1 control is effective. It has the effect of preventing

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a schematic structure of an engine speed control device according to an embodiment of the present invention, FIG. 2 is a block diagram showing the structure of an electronic control unit etc. shown in FIG. 1, and FIG.
The figure is a flowchart showing the main part of the operation according to one embodiment of the present invention, FIG. 4 is an explanatory diagram showing the relationship between the throttle opening value and the actual rotation speed, etc., and FIG. 5 is another embodiment of the present invention. FIG. 3 is a flow diagram of idle opening degree determination processing according to an example. In the figure, 1...engine, 3...intake pipe, 7...throttle valve, 8...throttle opening sensor, 9...
Idle switch, 10... Bypass conduit, 11...
- Air control valve, 12... Ignition coil, 13... Igniter, 17... Vehicle speed sensor, 20... Electronic control unit. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] A switch means is in a predetermined state when the throttle valve is in a predetermined opening range from fully closed, and detecting means detects an idle state from engine operating conditions including an output signal of the switch means; In the engine rotation speed control device, the detection means is configured to control the throttle valve from fully closed to the predetermined opening. An engine rotation speed control device, characterized in that the idle state is detected by detecting that the opening is within a predetermined opening range.