JPS63243430A - Idling speed controlling method for engine - Google Patents

Abstract

PURPOSE:To perform idling at time of restarting stably, by connecting an auxiliary passage with an on-off valve to the downstream side of a throttle valve, while opening this on-off valve as long as the specified time at the restarting when an engine is almost in the warm-up state, and making an air-fuel mixture feedable out of the auxiliary passage. CONSTITUTION:A solenoid-driven on-off valve 4 is installed in an auxiliary passage 3 bypassing the throttle valve 2 set up in a suction passage 1 for a carburetor or a gas mixer. And, at an electronic controller 5 inputting each output signal of a throttle switch 6, an engine temperature sensor 7 and an ignition switch 8, the on-off valve 4 is controlled so as to open it as long as the setting time at a timer 9 when the ignition switch 8 is selected from a starting position to an ignition position in the state that an engine is almost warmed up and the throttle valve 2 is placed in an idle position. By this constitution, an air-fuel mixture is fed to the engine from the auxiliary passage 3 whereby the engine speed is maintained at higher speed as long as the setting time.

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Application Field The idle speed control method according to the present invention is mainly used in controlling an automobile engine.

BACKGROUND OF THE INVENTION It is well known to increase the amount of fuel used to facilitate starting and idling when the engine is cold. In addition, in order to increase the engine rotational speed when an inspiratory load is applied during idling, it is also possible to introduce an air-fuel mixture downstream of the throttle valve. -87320, Utility Model Publication No. 62-2284, etc. (This is a known technique.

The problem that the invention aims to solve is that when the engine is cold, it is possible to increase the amount of fuel to make the engine stably idle at a specified rotational speed, but 2. For example, it is possible to increase the amount of fuel when the engine is cold. If the engine is restarted when it is almost warmed up after being left unattended, the idle rotation speed may be lower than the specified rotation speed and the engine may become unstable.

This phenomenon does not occur with injection systems that add engine temperature to the fuel flow rate correction element, but it does occur with suction systems that supply fuel under negative pressure, such as liquid fuel vaporizers and gaseous fuel mixers. This occurs when a fuel increase mechanism such as a carburetor's automatic choke device does not operate even though a slight increase in fuel is required.

SUMMARY OF THE INVENTION Therefore, the present invention provides a method that allows a stable idle link to be performed while leaving the throttle valve at the idle position when restarting an engine that is substantially warmed up.

The present invention connects an auxiliary passage having an on-off valve to the downstream side of the throttle valve in the intake path of the carburetor or mixer, and turns on the ignition switch when the engine is almost warmed up and the throttle valve is in the idle position. As a means to solve the above problem, the opening/closing valve is opened for a preset time to supply the air-fuel mixture through the auxiliary passage when the engine is moved from the starting position to the ignition position.

Operation: Start the engine and once it has warmed up completely or almost completely, stop the engine.

When the ignition switch is operated to restart the engine when it is almost warmed up before returning to the cold state and the throttle valve is in the idle position, and the engine is switched from the starting position to the ignition position, the mixture is mixed from the auxiliary passage. Air is supplied to increase the idle rotation speed.

According to the present invention, the air-fuel mixture is supplied from the auxiliary passage in conjunction with engine ignition even if the cold engine fuel increase mechanism does not operate in a temperature range where a slight increase in fuel is required, and the idle link at the time of restart is maintained. It is something that can be done in a stable manner. In addition, the auxiliary passage can be used to control the idle rotation speed when an electric load is applied, and W? It can be implemented with a simple mechanism.

Embodiment An embodiment of the present invention will be explained based on the layout diagram shown in FIG.

An electromagnetically driven on-off valve 4 is provided in an auxiliary passage 3 that bypasses a throttle valve 2 installed in an intake passage 1 of a liquid fuel vaporizer or gaseous fuel mixer. Furthermore, when electrical loads such as automobile headlights and air conditioning equipment, and drive loads such as power steering pumps are applied, electrical signals that detect the operation of these equipment are input to the electronic control device 5, and these Based on the 1-air signal, a drive signal is sent to the on-off valve 4 to open it during idle link.

A position sensor (throttle switch) 6 of the throttle valve 2 detects idle and off-idle, and an engine temperature sensor 7 detects the temperature of the engine coolant, and these electrical signals are input to the electronic control device 5. Ru.

Next, turn the ignition switch 8 to the starting position +i! ST,
Each ignition position IC is a starter motor.

It is connected to the timer 9 separately from the ignition coil, and the on-off valve 4
A two-position sensor 6 and an electronic control device 5 are connected to a timer 9.

Based on the electrical signal from the temperature sensor 7, an electronic control system detects temperature changes that require a slight increase in fuel during idling, that is, temperatures below approximately 50 degrees Celsius, in which the fuel increase mechanism does not operate when the engine is cold. When the device 5 makes a determination, it sends a signal to the timer 9. Also. The position switch 6 sends a signal to the timer 9 when the throttle valve 2 is in the idle position, thereby enabling the timer 9. When the ignition switch 8 is turned to the starting position (ST), the engine starts cranking and at the same time starter relay direct pressure is generated as shown in FIG. 2, and this is sent to the timer 9. When the starter switch 8 is placed in the ignition position IG, the starter relay heart pressure disappears, so the timer 9 operates for a preset time from when this disappears, and the battery 10
ignition switch 8. The timer 9 is sent to the ``'C on-off valve 4.

The on-off valve 4 is opened by the driving flow ii supplied for a set time like the second NB, and supplies the air-fuel mixture to the downstream side of the throttle valve 2.

Therefore, the engine rotational speed is maintained at a high rotational speed for a set period of time as shown in FIG. 2C.

Incidentally, the auxiliary passage 3 may be provided only for implementing the present invention, and in this case, the timer 9 is provided with the function of determining the engine temperature.

[Brief explanation of drawings]

FIG. 1 is a layout diagram of an embodiment of the present invention, and FIG. 2 is a diagram illustrating control of idle rotation speed. l...--Intake path, 2... Throttle valve, 3...
...Auxiliary passage, 4...Opening/closing valve, 5...
...Electronic control device. 6...Position sensor, 7...Temperature sensor, 8...Ignition switch, 9...
...Timer.

Claims (1)

[Claims] An auxiliary passage having an on-off valve is connected to the downstream side of the throttle valve in the intake path of the carburetor or mixer, and when the engine is almost warmed up and the throttle valve is in the idle position. A method for controlling an idle speed of an engine, characterized in that when an ignition switch is turned from a starting position to an ignition position, the opening/closing valve is opened for a preset time to supply an air-fuel mixture through the auxiliary passage.