JPS6263153A - Idle controller for engine - Google Patents

Abstract

PURPOSE:To prevent the reduction of the idle number of revolution by detecting the operation of the outside leads, such as an oil pump for power steering and a compressor for cooler, in idling and prohibiting the operation of the outside loads for a prescribed time after the start of these loads. CONSTITUTION:An idle controller 1 controls the idle number of revolution by adjusting the quantity of the air which bypasses a throttle valve 5 and adjusting the injection quantity of the fuel from an injector 6. In other words, a linear actuator 9 for driving a bypass valve 8 for opening and closing a bypass air passage 7 and an injector 6 are controlled by an ECU 16. The ECU 16 increases the output according to the increase of the load which operates upon the crankshaft 11 of an engine 2, accompanied with the operation of a variety of outside loads 12-15, and the idle number of revolution is kept constant. In this case, if an air conditioner switch 18 is turned-On, the operation of a compressor 13 for cooler is prohibited for a prescribed time after the start of the operation of other outside loads.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an engine idle control device for controlling load fluctuations during idle.

(Prior art) Conventionally, when an external load is applied to the engine during idling operation, for example, due to the operation of a power steering oil pump, a cooler compressor, etc., the idling speed is used to prevent the idling speed from dropping. An idle control device is known in which a correction function operates to increase the intake air amount by a predetermined amount (for example, Japanese Patent Application Laid-Open No. 1983-1999)
59038).

However, even in the case where idle control is performed in accordance with the operation of an external load as described above, when the external load starts to operate, the idle rotation speed may drop slightly due to reasons such as an intake delay. A certain amount of time is required to recover from the depression.

However, if other external loads operate during this time,
If the load further increases, the drop in the idle speed will become steeper, causing the engine speed to become unstable and possibly causing the engine to stop.

(Object of the Invention) In view of the above-mentioned circumstances, an object of the present invention is to provide an engine idle control device that suppresses large idle speed fluctuations caused by overlapping external load operations during a short period of time during idle. That is.

(Structure of the Invention) The idle control device of the present invention detects the operation of an external load such as a power steering oil pump or a cooler compressor during idle, and prohibits the operation of other external loads for a predetermined period of time after the load is activated. The invention is characterized in that it is provided with a control means for controlling.

(Effects of the Invention) According to the present invention, by prohibiting the operation of other external loads for a predetermined period of time after one external load operates, the number of idle revolutions due to the operation of one external load is reduced. By activating the next external load after the slump has recovered, it is possible to suppress large fluctuations in idle rotation caused by overlapping external load operations within a short period of time, and ensure stability in idle operation. It is something.

(Example) Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 shows the overall schematic configuration.

The idle control device 1 adjusts the amount of bypass air that bypasses the throttle valve 5 installed in the intake passage 4 that supplies intake air to the combustion seedling 3 of the engine 2, and adjusts the fuel injection port from the injector 6. It controls the rotation speed.

That is, a bypass air passage 7 is provided that bypasses the throttle valve °5, a bypass valve 8 is provided that opens and closes this bypass air passage 7 to adjust the amount of pass bus air, and the opening degree of this bypass valve 8 is actuated by a linear actuator 9. do. Furthermore, the amount of fuel injected from the injector 6 installed in the intake passage 4 is adjusted to change the supplied air-fuel ratio.

The crankshaft 11 of the engine 1 has a power steering oil pump 12 and a cooler compressor 1 as external loads driven by its rotational force.
3. A power generation alternator 14, a torque converter 15, etc. are installed.

The amount of intake air and the injector 6 are adjusted by adjusting the opening of the bypass valve 8 as the linear actuator 9 operates.
The fuel supply port is controlled by the control unit 16.
This is done by control signals from. The control unit 16 receives a signal from the idle switch 17 to detect the idle operating state, a signal from the air conditioner switch 18 that instructs the user to operate the cooler, a signal indicating the operating state of the power steering oil pump 12, A signal indicating the power generation state of the alternator 14, a signal indicating the operating state of the torque converter 15, and the like are input, respectively. Furthermore, the operation (driving/stopping) of the cooler compressor 13 is controlled by this control unit 16.

That is, the control unit 16 controls the operating state of the power steering oil pump 12, the operating state of the torque converter 15, the power generation state of the alternator 14,
In response to a signal indicating the operating state of the cooler compressor 13 by operating the air conditioner switch 18, that is, in response to the operation of these external loads, the crankshaft 1 of the engine 1
The intake air volume and fuel supply port during idling are controlled in accordance with increases and decreases in the load acting on the engine, and by increasing the intake air volume and fuel supply volume when the external load increases, the output can be adjusted in response to the increase in load. The idle speed is controlled to increase and keep the idle speed constant. Roughly speaking, the control unit 16 operates the cooler compressor 13 when the air conditioner switch 18 is turned on. 13 is prohibited and controlled to operate after a predetermined period of time has elapsed.

Figure 2 shows the basic operation, where (A) shows the fluctuation in the engine speed (idle speed), (B) shows the change in the intake air amount, and (
C) shows changes in the fuel injection amount. first,
At point a in the idling state, the power steering oil pump 12 operates to increase the load, increasing the intake air and fuel injection m, but there is a time delay until the engine output actually increases. Therefore, the engine speed decreases. When the air conditioner switch 18 is turned on at point b in the process of decreasing the engine speed, if the cooler compressor 13 is activated immediately, the engine speed will further decrease as shown by the broken line due to the increased load. I end up. However, the control unit 16 prohibits the operation of the compressor 13 for a predetermined time T after the operation a of the power steering oil pump 12, and by the time T elapses, the intake air amount and the fuel injection amount have increased and the engine The rotation speed will recover. Then, as the predetermined time T elapses, the compressor 13 is operated at the 0 point, and the intake air amount and fuel injection m are increased accordingly,
The engine speed decreases at the beginning of the operation of the compressor 13, but quickly recovers and further increases at -, and is controlled to a high idle speed in order to increase the cooling capacity of the cooler.

The operation of the control unit 16 will be explained based on the flowchart shown in FIG. This flowchart shows only the main parts. In step S1, it is determined whether the idle operation is in progress based on the operation of the idle switch 17, and if YES in the idle state, in step S2, whether or not an external load other than the cooler compressor 13, such as the power steering oil pump 12, etc. is in an operating state. Determine whether or not.

When the external load is ON and is in operation, in order to check whether the load is in the state immediately after activation, it is determined in step 83' whether there has been an increase in the external load other than the cooler compressor 13', and the load is When the result is YES, a timer t for prohibiting the operation of the compressor 13 is set to a predetermined time T.

When the timer t is set, the next step S3
The determination becomes No, and the process proceeds to step S5, where it is determined whether or not the timer t has reached O.

If the timer t has not reached 0 (No), step S7
After decrementing the timer t, step S8
The permission flag F is reset to O.

On the other hand, the timer t becomes O and the determination in step S5 is Y.
When it becomes ES, the permission flag F is set to 1 in step S6. Further, when the operating state is other than idle and the determination in step S1 is No, or when the load other than the cooler compressor 13 is OFF in step S2,
The permission flag F is similarly set to 1 in step S9.

When the permission flag F is reset to O, even if the air conditioner switch 18 is turned on, the compressor 1
This prohibits the driving of 3.

That is, step S10 is the previous air conditioner switch 1.
8, and when it is OFF, the current state of the air conditioner switch 18 is determined in step 813. When the air conditioner switch 18 is turned on for the first time, the process proceeds to step 814 based on the ON determination in step 813.
Here, it is determined whether the permission flag F is set to 1 or not. When the timer t is decrementing and the permission flag F is reset to 0, the process waits until the determination in step 314 becomes YES. When the predetermined time fllT set in the timer t has elapsed and the timer t becomes O and the permission flag F is set to 1, the step S14
If the determination is YES, the compressor 13 is driven in step S15, and in response to this cooler operation, predictive control is performed to increase the intake air amount, and fuel correction is performed to increase the fuel injection amount.

Also, if the previous air conditioner switch 18 was ON, step 8
10 to step S11, the current state of the air conditioner switch 18 is determined, and the current state of the air conditioner switch 18 is determined.
is turned OFF, the compressor 13 is turned off in step 812.
In addition to stopping the drive of the engine, a prospective correction is performed to reduce the amount of intake air.

On the other hand, when the previous air conditioner switch 18 was ON and the current air conditioner switch 18 is also ON, and when the previous air conditioner switch 18 was OFF and the current air conditioner switch 18 is also OFF, that is, the state of the air conditioner switch 18 changes. When the Ill III state is not changed, the Ill III state is maintained unchanged.

According to the above embodiment, the cooler compressor 1
3, even if the air conditioner switch 18 is operated, it is not driven for a predetermined period of time due to the operation of other external loads, thereby preventing the drop in idle rotation speed as shown by the broken line in Fig. 2 and stabilizing it. It is possible to maintain idle operation.

In the above embodiment, the cooler compressor 13 is an example of the external load whose operation is prohibited, but the operation of other external loads that have little effect even if the operation timing is slightly shifted may be similarly prohibited. Good too.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the overall configuration of an engine equipped with an idle control device according to an embodiment of the present invention. FIG. 3 is a characteristic diagram showing changes in the number of revolutions, and FIG. 3 is a flowchart diagram for explaining the operation of the control unit. 1... Idle control device 2... Engine 4... Intake passage 5...
Throttle valve 7...Bypass air passage 8...
... Bypass valve 9 ... Linear actuator 12 ... Power steering oil pump 1
3... Cooler compressor 14...
・Alternator 15...Torque converter 16...Control unit 17...
・Idle switch 18... Air conditioner switch Figure 2

Claims (1)

[Claims] (1) In an engine idle control device that increases the amount of intake air at idle by a predetermined amount when an external load is applied during idle due to the operation of a power steering oil pump, a cooler compressor, etc. 1. An engine idle control device comprising control means for detecting the operation of the load and prohibiting the operation of other external loads for a predetermined period of time after the load is activated.