JPS59226249A - Apparatus for controlling idling speed of engine - Google Patents

Abstract

PURPOSE:To enable to control the idling speed appropriately according to the temperature of cooling water, by effecting estimated correction of load according to the types of load and the temperature of cooling water at the time, and correcting a correction value according to the change in the engine speed at the time when estimated correction of load is executed. CONSTITUTION:A control valve is disposed in a by-pass passage by-passing a throttle valve in an intake passage, and the control valve is so controlled by a feedback control means that the engine speed detected by an engine-speed sensor is converged to an aimed idling speed. A control apparatus of this invention comprises further a memory means which stores a correction value for correcting a feedback control value by an amount corresponding to the level of load in the manner of relating to the temperature of cooling water when output signal of a load detecting means for detecting operation of external loads such as a cooler is given to the memory means. Further, the control apparatus of this invention comprises a correction-value correcting means which increases the above correction value by a prescribed amount when the external load are operated and the engine speed is lowered resultantly and decreases the correction value by a prescribed amount when the engine speed is raised extraordinarily.

Description

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

(Prior Art) In an automobile, it is known that idle rotation control is performed in order to obtain stable idle rotation when the engine is in an idle state. This control detects the engine speed, compares it with a preset target idle speed, and performs feedback control of the intake air amount. When the engine speed exceeds the target idle speed 'f, the intake air When the engine speed decreases and the engine speed falls below the target idle speed, the intake air St? controlled to increase.

On the other hand, when an external load of the engine such as a cooler is activated, the temporary rotation that occurs is controlled according to the load value when the external load is activated in order to prevent the rotation from dropping and to converge to the target idle operation as quickly as possible. It is known to perform so-called expected correction to increase the IF. The purpose of the estimated correction is to quickly obtain stable idle rotation in response to changes in external load as described above, so it is desirable that the correction value of the estimated correction be an appropriate value.

The applicant is Tokugansho! f;7-/3g In No. 296,
Considering that the appropriate correction value will change due to differences in the characteristics of each manufactured engine, changes in characteristics over time, etc.,
An idle rotation control device is disclosed in which a correction value is replaced with an optimum correction value at the time when stable idle rotation is obtained. However, since the appropriate correction value differs depending on the engine temperature, that is, during warm-up operation and during normal operation, it is not possible to perform sufficient control simply by considering differences in engine characteristics.

(Object of the present invention) Therefore, an object of the present invention is to perform the estimated correction for the external load corresponding to the state of the engine temperature by changing the correction value of the estimated correction in accordance with the state of the engine cooling water temperature. The object of the present invention is to provide an idle rotation control device that can perform highly reliable and stable control.

(Configuration of the present invention) The above object of the present invention can be achieved by the following configuration. That is, the present invention includes a water temperature detection means for detecting the engine cooling water temperature, a rotation speed detection means for detecting the engine rotation speed, a control valve for controlling the intake air amount e flt, and a control valve that controls the engine rotation speed and the target idle rotation speed. Feedback control means determines a control value so that the rotation speed converges to the target idle rotation speed, and outputs a full control signal to the control valve, and when an external engine load such as a cooler operates, storage means for storing a correction value for correcting the control value by a predetermined amount in accordance with the engine cooling water temperature; load detection means for detecting the entire operation of the external load; and a drop in rotational speed when the external load is activated. The present invention is characterized in that it includes a correction value modifying means that increases the correction value by a predetermined amount when this occurs, and decreases the correction value by a predetermined amount when an increase in rotational speed occurs.

The configuration of the present invention will be explained with full reference to FIG.

The feedback control means determines a control value based on a preset target idle rotation speed and a rotation speed signal from a rotation speed sensor, and outputs a control signal to the control valve. The storage means stores correction values corresponding to the type of external load and the cooling water temperature as a MAP. When the cargo pick-up is activated, it is detected by the load detection means, and the load correction value corresponding to the cooling water temperature at that time detected by the water temperature detection means is read out from the storage means, and the load is detected by the load detection means. It is added to the control value of the control means and input to the control valve as a control signal. That is, estimated correction is performed. At this time, the correction value modification means increases the correction value by a predetermined amount if there is a drop in the rotation speed, and decreases the correction value by a predetermined amount if the rotation speed increases. This corrected correction value is replaced with a corresponding water temperature correction value in the storage means.

(Effects of the present invention) As described above, in the present invention, the estimated load correction is performed based on the load a.
Since it is carried out in accordance with Class I and the engine cooling water temperature at that time, it is possible to make the appropriate table estimate correction according to changes in operating conditions, and the correction value can be corrected depending on the change in rotation speed at the time of estimate correction. As a result, appropriate values are maintained according to individual differences in engine characteristics and changes over time.
Therefore, stable idle rotation control can be performed at all times.

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

21) System Configuration Referring to FIG. 2, the engine body 10 includes a cylinder block 16 having 14 cylinder pipes in which a piston 12 slides, and a combustion chamber 1 attached to the upper part of the cylinder 14.
8 and a cylinder head 20 forming a cylinder head 8. An intake pipe 22 and an exhaust pipe z4 are connected to the cylinder head 20, respectively.

Further, the cylinder head 20 is formed with a negative portion of an intake passage 26 and a part of an exhaust passage 28 that communicate with the intake pipe 22 and exhaust pipe 24 . An intake valve 82 is located at the opening of the intake passage 26 to the combustion chamber 18, that is, the intake portion 80.
Exhaust valves 36 are connected to the openings of the exhaust passages 28 to the combustion chamber 18, that is, exhaust ports 84, respectively. An air cleaner 88 is provided at the tip of the intake passage 26.

An air flow meter 40 for measuring the total amount of 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. Also,
The intake passage 26 is provided with a pinot gas passage 46 that bypasses the throttle valve 41;
A proportional solenoid valve 48 is installed to adjust the rush air ffi'ff flowing therethrough. Furthermore, in the intake passage 26,
A throttle valve strength sensor 50 that detects the opening degree of the throttle valve 42 is provided.

In order to control the fuel injection nozzle 44 and the proportional solenoid valve 48, a control unit 52, preferably composed of a microcomputer, is installed.

The device in this example is a rotation speed sensor v5 that detects the engine rotation speed.
The signal from the sensor 54 is input to the control unit 52. Signals from the air flow meter 40 and throttle opening sensor 5 ('' are also input to the control unit 52. In addition, signals from a water temperature sensor 56 that detects the cooling water temperature are also input to the control unit 52.Furthermore, the control unit 52 receives an ON-OFF signal from various engine-equipped products such as a cooler, that is, an engine load 58.

b) Control Flow In controlling the above system, a main program and an interrupt processing program are used in this example.

A flowchart of the main program is shown in Figure 3. The main log 2 detects whether or not external loads on the engine such as coolers, power steering, frost, sudden loads, etc. are operating or stopping, and when a load is stolen, it detects the operation or stoppage of each load. Depending on the engine coolant temperature at that time, a load correction value stored in advance as a MAP is selected and estimated correction is performed. When the external load is operating, when the load is not operating, the load correction value is added to the basic control value determined according to the difference between the rotation speed and the target idle rotation speed, and the value is proportional to the control signal. lunoid valve 48 to control the suction nitrogen atmosphere. In the main program, each variable, memory, etc. are first initialized (S
,). Next, the water temperature detected by the water temperature sensor 56 is A/
D conversion is performed (S2). Since the appropriate load correction value varies depending on the engine temperature, in this example, each appropriate load correction value is included as a MAP for the engine cooling water temperature, which has a close relationship with the engine temperature. Therefore, in order to read out the load correction value for that water temperature, it is necessary to perform A/D variation of the water temperature. Next, the operating state of each external load is detected, and when the load is operating, a prospective correction is performed for each type of load and the engine cooling water temperature at that time (S6, S4,
S5, S6, S7, S8, S9.510). In this example, the determination of whether the external load is operating is to determine whether the cooler is operating (S5), whether the gear is idling in the drive shift position or idling in the neutral position (S5), and whether the cooler is operating (S5). - It is determined whether the tearing device is operating (S,) and whether other electrical loads are operating (S,).

The interrupt processing program interrupts the main program at a predetermined timing and changes the expected correction value ft according to the rotation speed fluctuation situation when the load is operating, and also changes the expected correction value ft according to the difference between the rotation speed and the target idle rotation speed. Accordingly, the timing for output processing to the proportional solenoid valve 48 is determined by the signal from the rotation sensor, and the cycle of the output from the rotation sensor is measured (SS,). Next, the number of revolutions is calculated based on this period (S S2). Next, for load operation, for example, for cooler operation, a map of load correction values for cooling water temperature is stored in memory for each load, as shown in FIG. The value for the water temperature during operation is read and the estimated correction is performed in the main program, so it is determined whether the drop in rotation speed due to this estimated correction exceeds the predetermined If, and if it exceeds the estimated correction value of the cooler. Pwc is a predetermined value Δ
Increased by Pwc (SS, ss8, ss4.5s
5). Furthermore, if the expected correction by the main program causes upward blowing and is greater than a predetermined amount, the estimated cooler correction value Pwc is reduced by a predetermined value ΔPwc (SS3, SS,', ss6, SS, ). next,
When there is a change in the correction value Pwc, the M shown in FIG.
AP exchange takes place (ss8, ss, ).

That is, the above-mentioned changed correction value is newly stored in correspondence with the cooling water temperature when the cooler is in operation. In addition, Steve SS4
The operations from to Stella 7aSS are performed in the same way for external loads other than the cooler. When the external load does not operate, the steps from step S54 to step SS are performed.

The following operations are performed without mutual intervention. That is, it is determined whether the rotational speed is within the dead zone region where the food pack cannot be controlled (SS,), and if it is within the dead zone region, the feedback control is stopped by 1q and is not switched to the oven control (SS). SS,,). If it is outside the dead band region, that is, ΔN>, it is compared with the target engine speed, and the feed/pull control car is operated according to the difference (SS, 2, ss, 3). .5s1
4). If the rotational speed is higher than the target rotational speed, the control value will be decreased to lower the rotational speed.If the rotational speed is lower than the target rotational speed, the rotational speed will be lowered. A υ3buf process is performed to raise the temperature. Therefore, the load correction value σ) MAPt is always changed to an appropriate value in accordance with the engine cooling water temperature, thereby ensuring reliable eye I.
S rotation control can be performed.

[Brief explanation of drawings]

Figure i/ is a diagram corresponding to the claims of the present invention, Figure 2 and Figure 2 are system configuration diagrams of the device according to the present invention, Figures 3 and 3 are flowcharts of embodiments of the invention, and Figure S is a load correction value. This is an example of MAPO. Explanation of symbols 10...Engine body, 12...Piston, 14.
...Cylinder, 26...Intake passage, 28...Exhaust passage, 88...Air cleaner, 41O...Air flow meter, 42...Throttle valve, 441...Fuel injection nozzle, 4.8. ...Proportional solenoid valve, 50...
Throttle valve opening sensor, 52...control unit, 5
ヰ...Rotation speed sensor, 56...Water groove sensor. Patent applicant: Toyo Kogyo Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] A water temperature detection means detects the engine cooling water temperature, a rotation speed detection means detects the engine rotation speed, a control valve controls the intake air amount, and the engine rotation speed is compared with the target idle rotation speed to determine the target rotation speed. Feedback control means that determines a control value so as to converge to the idle speed and outputs a control signal to the control valve, and controls a predetermined amount according to the size of an external engine load such as a cooler when it is activated. storage means for storing a correction value corresponding to the engine cooling water temperature; load detection means for detecting operation of the external load; and storage means for storing a correction value corresponding to the engine cooling water temperature; An idle rotation control device for an engine, comprising a correction value correcting means for increasing the correction value by a predetermined amount and decreasing the correction value by a predetermined amount when a speed increase occurs.