JPS59226246A - Apparatus for controlling idling speed of engine - Google Patents

Abstract

PURPOSE:To prevent engine stall at the time when the engine operation is returned to idling operation, by providing a judging means which makes comparison between the rate of change in the opening of a throttle valve and the rate of change in the signal for controlling the opening of the throttle valve and judges that an engine is not in idling operation in case that the former is greater than the latter. CONSTITUTION:In a control apparatus for controlling the opening of a throttle valve at the time of idling operation of an engine according to the control value that is determined from the deviation between an aimed idling speed determined by a control means and the actual engine speed detected by an engine-speed detecting means, there is provided a judging means to which a throttle-valve opening signal given from an opening detecting means and a signal given from a signal detecting means for detecting the output signal of the control means are furnished. The judging means calculates the rate of change in the opening of a throttle valve and the rate of change in the control signal from the above two signals, comparison is made between the above two rates of change. In case the former is greater than the latter, judgement is made that the engine is not in idling operation. When the above judgement is made, supply of the control signal from the control means to the throttle valve is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an idle rotation control device for converging engine rotation speed to a target idle rotation speed during idle operation.

(Prior Art) In an automobile, it is known to perform idle rotation control in order to obtain stable idle rotation when the engine is in an idling state. This control detects the engine rotation speed, compares it with a preset target idle rotation speed, and adjusts the opening of the throttle valve to control the amount of intake air.The target rotation speed is 95 rotations. When the engine speed exceeds the idle speed, the intake air amount is decreased, and when the engine speed falls below the target idle speed, the intake air amount is increased. However, since the above device is related to control in the idling state, if this control is performed in the non-idling state, the control value will be small.
When the engine returns to idle, the throttle opening is suddenly reduced (9) The intake air volume is insufficient, causing problems such as engine stoppage. Therefore, in such an idle rotation control device, how to determine whether it is in an idling state or a non-idling state that has come out of an idling state is important in ensuring control reliability. .

No. 37-729230 discloses that a deviation between a target throttle opening signal determined according to the difference between a set engine rotation speed and an actual engine rotation speed and an actual throttle opening signal is detected, and this deviation is An idle rotation control device has been disclosed which determines that the engine is in an idling state when it is within a set value, and performs feedback control of the throttle valve opening, that is, the intake air, so that the deviation is eliminated. This device has the advantage of being compact because it detects the non-idling state in a rectangular manner. Therefore, there is a problem in that it is not possible to adequately respond to individual differences in engine characteristics, that is, variations. In this way, if it is possible to accurately detect the transition to the non-idling state, it is possible to use conventional devices that fix the control value at that time when the non-idling state occurs. , the fixed value becomes a small value. Then, when returning from deceleration to A/F, the control is not in time, resulting in a drop in rotational speed or engine stoppage.

(Object of the present invention) Therefore, the object of the present invention is to provide a device for solving the above-mentioned drawbacks, which quickly determines the idling state and the non-a/f-link state, and prevents problems such as engine stop when returning to idling. The objective is to provide a reliable idle rotation control device that will prevent this from occurring.

(Structure of the present invention) In order to achieve the above object+S, the present invention is structured as follows. That is, the present invention provides an engine having a control means for controlling the opening degree of a throttle valve during idling operation to fully adjust the intake air amount to the engine so as to control the engine speed to converge to a target idle speed. In the A/R rotation control device, a detection means detects the opening degree of the throttle valve, a signal detection means detects the opening degree control signal of the throttle valve of the control means, and a signal from the two detection means. and determining means for comparing the rate of change of the throttle valve opening and the rate of change of the throttle valve opening control signal, and determining that the non-idle operating state is present when the rate of change of the throttle valve opening is large. It is characterized by:

The configuration of the present invention will be explained with reference to FIG. The engine rotation speed is input to the control means, and the control means determines a control value according to the difference between the target idle rotation speed and the engine rotation speed, and outputs a control signal to the throttle valve. The determining means receives signals from the opening detection means for detecting the throttle opening and the signal detection means for detecting the signal from the control means, processes the throttle opening change rate and the control signal change rate, and compares the two. If the rate of change in throttle opening is large, it is determined that the vehicle is in a non-idling state. In other words, when there is a change in opening that exceeds the control command, it is determined that a non-A/F link state is present.

In that case, the control signal to the throttle valve is stopped.

(Effects of the Present Invention) According to the present invention, as described above, the non-idling state is determined by comparing the actually measured throttle opening change rate with the control signal change rate determined based on the difference between the target idling speed and the measured speed. This is done by comparing. This rate of change is independent of engine characteristics) and is therefore unaffected by individual product differences. Furthermore, since this determination process is not electrically performed, it is quick and accurate. Furthermore, since the idle can be returned to the idle state using a relatively large control value at the moment when the non-idling state is reached, problems such as engine stoppage do not occur when the engine returns to the idle state.

(Explanation of Examples) Embodiments of the present invention will be described below with reference to the drawings.

a) System configuration Referring to FIG. 2, the engine main body 10 is composed of a cylinder 14 in which all internal pistons 12 slide. a cylinder block 16 having a combustion chamber 1 attached to the upper part of the cylinder 14;
8? A cylinder head 20 is provided. An intake pipe 22 and an exhaust pipe 24 are connected to the cylinder head 20, respectively.

Further, in the cylinder head 20, a part of an intake passage 26 and a part of an exhaust passage 28, which communicate with the intake pipe 22 and the exhaust pipe 24, are formed. An intake valve 82 is provided at the mouth of the intake passage 26 to the combustion chamber 18, that is, at the intake port 80.
Exhaust valves 86 are assembled at the openings of the exhaust passages 28 into the combustion chamber 18, that is, at the exhaust ports 8. An air cleaner 88 is provided at the tip of the intake passage 26.

An air flow meter 40 for measuring air is provided on the downstream side thereof, and a throttle valve 42 is provided further downstream thereof. Intake port 80 of intake passage 26
A combustion injection nozzle 44 is arranged nearby. In the device of this example, when performing idle rotation control, the throttle valve 42
The actuator 46 is provided with an actuator 46 for adjusting the opening degree of the throttle valve 42, and this actuator 46 is adapted to adjust the throttle valve 42 to all target positions at once by manipulating the position of the idle stop lever for the throttle valve. ing. When not idling, the actuator 46 is inactive;
The stopper f is located away from the throttle valve 42. Further, the intake passage 26 is provided with a throttle valve opening 1i*nv50 for detecting the opening degree of the throttle valve 42.

To control the operation of the fuel injection nozzle 44 and the actuator 46, a control unit 52, preferably consisting of a microcomputer, is mounted. The device of this example is equipped with a rotation speed sensor 54 for detecting the engine rotation speed.
A signal from this sensor 54 is input to the control unit 52. Signals from the air flow meter 4o and the throttle opening sensor 50 are also input to the control unit 52. Further, a signal from a water temperature sensor 56 that detects the cooling water temperature is also input to the control unit 52. Zurani, control unit 5
2, an ON-OFF signal of various engine accessories such as a cooler, ie, an engine load 58, is input. The control unit 52 determines a control value, controls the solenoid of the actuator 46, outputs all signals, and performs duty ratio control.

b) Control Flow FIG. 3 shows a flowchart of the control program in this example.

In the first stage of this program, predetermined variables are initialized (S,), and the idle mode determination memory IDL, which indicates whether the system is in the idling state, is turned OFF [, that is, the mode is set to non-adol mode. The idle return throttle opening degree memory PIDL, which indicates the throttle opening degree at which the throttle opening is set and returns to the idling state, becomes a very large value (ω), and the control value memory D1 becomes 0, and the engine rotation speed at which the engine speed returns to the idling state is set to a very large value (ω). The idle return rotation speed memory RIDL shown is set to a predetermined value.

Note that R1oLl'i is initialized to a very large value (co) at the first step fS when this flow starts, but after that, a regular predetermined value is used. Next, throttle opening Pt and engine speed R
6 reading operation is performed (s2).

Then, a determination is made as to whether the current mode is idle mode or non-idle mode (S,). Since the mode judgment memory IDL is set to OFF at the time of starting,
As the next process, a determination is made as to whether the conditions for returning to the idle mode are satisfied (S4, S5).

That is, it is determined whether the rotational speed R0 is less than or equal to the return rotational speed RIDL (S4) and whether the throttle opening Pt is less than or equal to the return throttle opening PIOL (S5). If the corner return condition is satisfied, please write a judgment memo! JIDL is set to ON, and other conditions are set (S8). That is, POFIDL
(throttle valve opening change value that is the standard for determining non-idling) is O, Dll (previous feedback control value Dt based on the difference between the actual engine speed and the target idle speed) ) to 0,
Same (P, sets the previous value Pt-1 to 0.

Next, the rotational speed difference △R between the target idle rotational speed R and the rotational speed Rt, the throttle opening P when executing this Grodarum last time, -1 and the throttle opening P when executing this time
, that is, the opening change △P is calculated (S,)
. Next, a determination is made whether to transition to non-idle mode (S,.).

This judgment is a function of the rotational speed difference △R, and is determined by the rate of change of the control value O5, where Dt2 and △R(1 are constants).
S1o). That is, the determination is made by comparing the magnitude of the change rate of the control signal and the actually measured throttle opening degree change rate. If the actual throttle opening change ΔP is large as shown in FIG. 3, it is considered that the throttle valve 4z is artificially opened, and therefore the mode shifts to the non-idle mode. However, the reference value P corresponds to the rate of change of the control signal. If FIDL is large or significant, it is considered to be in an eye P ring state, and in that case, the control value O0 is calculated and a new reference value P is calculated. , 1. L is calculated (Sl,). Then, the output value O"Dt +Dbase of the control signal is calculated (S7). The control value DbaGe is the target rotation speed R
This is a basic control value determined based on 0. Next, write failure processing for a predetermined variable is performed (S12), and a timer sets a predetermined time interval, for example, a2! m5ec
Time management is performed to execute Glodarum at intervals (S, , ). Note that if it is determined in steps S4 and S that all of the idle return conditions are not satisfied, 0 is set in the control value (S6). Also, step S. If the state shifts to non-idle based on the judgment, the judgment memo IJIDL is set to OFF, and the throttle opening P, -1 at the time of non-idle judgment is used as the return throttle opening P (S, 4). ).

Through the above processing, it is possible to quickly and accurately determine when to transition to non-idle mode.

[Brief explanation of the drawing]

Fig. 1 is a diagram corresponding to claims of the present invention, Fig. 2 is a system configuration diagram of an apparatus according to the present invention, Fig. 3 is a flowchart according to an embodiment of the present invention, and Fig. 1I is a relation between throttle rotation and time. This is a graph showing everything. Explanation of symbols 1O...Engine body, 12...Piston, 14...
°. cylinder, 26...intake passage, 28...exhaust passage,
88...Air cleaner, 40...Air flow make! 2. Throttle valve, 44 Fuel injection nozzle, 4.6 Actuator valve, 50 Throttle valve opening i sensor, 52 Control unit, 54...
・Rotation speed sensor, 56...Water temperature sensor. %Fi - Skewer Toyo Kogyo Co., Ltd. Figure 1 Figure 2 I: 18

Claims (1)

[Claims] An engine idle rotation control device having a control means for controlling the total intake air amount to the engine by controlling the opening degree of a throttle valve during idle operation so as to control the engine rotation speed so that it converges at a target idle operation, a detection means for detecting the opening degree of the throttle valve; a signal detection means for detecting the throttle valve opening control signal of the control means; and a change in the throttle valve opening degree by processing the signals from the two detection means. The idling speed of the engine is determined by comparing the rate of change of the control signal of the throttle valve and the rate of change of the throttle valve opening and determining that the rate of change of the throttle valve opening is large and the engine is in a non-idling operating state. Control device.