JPH03217639A - Auxiliary air controller of fuel injection valve - Google Patents

Abstract

PURPOSE:To solve abnormality early and prevent the increase of harmful components in exhaust gas by opening or closing a sub intake passage forcibly at the time of a particular operating condition, and generating a signal of abnormality based on the detection value of a detection means at the time of changing over an opening or closing condition. CONSTITUTION:To promote the atomization of fuel from fuel injection valves 5 during warming-up operation, a sub intake passage 6 is opened by energizing a solenoid valve 9 when engine cooling water temperature is less than approx. 40 deg.C, so that auxiliary air is supplied to the periphery of the nozzles of the respective fuel injection valves 5. When engine cooling water temperature is over approx. 80 deg.C, a neutral and idling conditions are kept and engine speed is stable, auxiliary air is supplied by opening a sub intake passage 6 for prescribed seconds, the engine speed increases. At this time, for example, when one of branch passages 6a is clogged, auxiliary air is not supplied, so the increase in engine speed is restrained. It is thus possible to generate a signal of abnormality when maximum engine speed in prescribed seconds for which the sub intake passage 6 is opened is less than a preset one.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an auxiliary air control device for a fuel injection valve that promotes atomization of fuel by supplying auxiliary air around the nozzle of the fuel injection valve. .

[Prior Art] Generally, when an engine is not warmed up, the atomization of fuel from the fuel injection valve is insufficient, resulting in poor ignitability of the air-fuel mixture in the combustion chamber. For this reason, for example, Japanese Patent Application Laid-Open No. 57-176339 discloses a technique for improving ignition performance by supplying auxiliary air around the nozzle of a fuel injection valve to promote atomization of the fuel. .

In addition to the main intake passage that supplies combustion air to the internal combustion engine, there is also a sub-intake passage that bypasses the throttle valve in the main intake passage and supplies auxiliary air around the nozzle of the fuel injector. The engine is equipped with an on-off valve that opens and closes the intake passage, and supplies auxiliary air around the nozzle of the fuel injection valve depending on the operating state of the engine.

In addition, by promoting fuel atomization and atomization, harmful components (HC, Co
etc.) can be reduced.

[Problems to be Solved by the Invention] In reality, in the case of a multi-cylinder internal combustion engine, a fuel injection valve is installed in each cylinder, so the auxiliary intake passage is connected to each fuel injection valve from downstream of the on-off valve. It is branched and piped.

Therefore, for example, if the branch passage becomes clogged or has a hole in it and air stops flowing, not only will the promotion of fuel atomization be inhibited, but one harmful component in the exhaust gas will increase. become.

However, in the past, no device has been invented to detect abnormalities such as blockage or holes in the branch passage.

The present invention has been made based on the above-mentioned circumstances, and its purpose is to provide an auxiliary air control device for a fuel injection valve that can detect abnormalities such as blockages and holes in branch passages. be.

[Means for Solving the Problems] In order to achieve the above object, the present invention employs the following technical means.

a main intake passage that communicates with a combustion chamber of an internal combustion engine and is provided with a throttle valve therein; a fuel injection valve provided in the main intake passage downstream of the throttle valve; and a fuel injection valve that bypasses the throttle valve. a sub-intake passage for supplying auxiliary air around a nozzle of a fuel injection valve; an opening/closing means interposed in the sub-intake passage for opening and closing the sub-intake passage; and a detection unit for detecting an operating state of the internal combustion engine. control means for controlling the opening and closing of the opening and closing means in accordance with a detected value of the detection means; and a control means for forcibly switching between opening and closing operation of the opening and closing means when the internal combustion engine is in a specific operating state. The apparatus includes a switching means, and an abnormality signal generating means for determining an abnormality based on a detection value of the detection means when the switching means is activated and generating an abnormality signal.

[Operation] The present invention having the above configuration opens and closes the auxiliary intake passage by forcibly opening and closing the opening and closing means when the internal combustion engine is in a specific operating state. At this time, it is determined whether or not an abnormality has occurred in the device based on the magnitude of the detection value of the detection means when the opening/closing means is switched between the opening operation and the closing operation. In case of abnormality,
Performs control in the event of an abnormality based on the abnormality signal.

[Effects of the Invention] According to the present invention having the above-described effects, when the internal combustion engine is in a specific operating state, an abnormality in the device is determined based on the detected value of the detection means accompanying the opening/closing operation of the opening/closing means, and an abnormality signal is output. can occur.

Therefore, abnormalities in the device can be resolved at an early stage, and an increase in harmful components in the exhaust gas can be prevented.

[Example] Next, an auxiliary air control device for a fuel injection valve according to the present invention will be explained based on an example shown in the drawings.

FIG. 1 is a schematic overall view of an auxiliary air control device for a fuel injection valve.

Fuel injection valve auxiliary air control device (hereinafter referred to as this device)
Reference numeral 1 denotes a main intake passage 4 for supplying combustion air to a combustion chamber 3 of an engine (internal combustion engine of the present invention) 2, and a fuel injection valve 5 disposed in the main intake passage 4 near the combustion chamber 3. and a sub-intake passage 6 for supplying auxiliary air around the nozzle. The auxiliary intake passage 96 is provided to the main intake passage 4 so as to bypass the throttle valve 7 disposed within the main intake passage 4 .

In the sub-intake passage 6, in order to open and close the sub-intake passage 6,
An electromagnetic valve (opening/closing means of the present invention) 9 whose energization is controlled via a control circuit (control means of the present invention) 8 is interposed. Note that the solenoid valve 9 opens when energized and closes when energization is stopped.

The auxiliary intake passage 6 supplies auxiliary air to each fuel injection valve 5 arranged according to the number of air intakes in the engine 2.
The piping is branched downstream from the solenoid valve 9.

The control circuit 8 includes a water temperature sensor 10 that detects the engine cooling water temperature, and an engine rotation sensor 1 that detects the engine rotation speed.
1, and an air flow meter 12 that detects the amount of intake air.
It is provided with various detection means for detecting the operating state of the engine 2, such as the above, and controls the energization of the electromagnetic valve 9 according to the detection values of the respective detection means.

Note that the energization control of the solenoid valve 9 during warm-up of the engine 2 is performed based on the engine cooling water temperature. For example, when the detected value by the water temperature sensor 10 is less than 40°C, the electromagnetic valve 9 is energized, and when the value is 40°C or higher, the energization is stopped.

In the control circuit 8 of this embodiment, a program is especially set for determining an abnormality when the branch passage 6a of the sub-intake passage 6 is clogged.

If the control circuit 8 determines that there is an abnormality, an alarm lamp (not shown) provided on the instrument panel of the driver's seat (not shown) can be turned on to notify the user of this fact.

The operation of the control circuit 8 for determining abnormality will be explained below based on the flowchart shown in FIG.

First, in step S1, it is determined whether the detected value by the water temperature sensor 10 is 80° C. or higher.

If the determination result in step S1 is YES, it is determined in step S2 whether the transmission (not shown) is in neutral. If the determination result in step S2 is YES, it is determined in step S3 whether or not the vehicle is in an idle link state. If the determination result in step S3 is YES, in step S4, the engine speed N
Determine whether e is stable. If the determination result in step S4 is YES, in step S5, the solenoid valve 9
The current is forcibly energized for a predetermined period of time (for example, 5 seconds) (switching means), and the process proceeds to step S6.

It should be noted that if the determination results in step S1, step S2, step S3, and step S4 are each NO, the program is ended immediately.

In step S6, it is determined whether the maximum engine rotational speed 1118XNe during a predetermined second when the electromagnetic valve 9 is energized is smaller than a preset value U.

If the determination result in step S6 is YES, in step S7 it is determined that there is an abnormality and the alarm lamp is energized (abnormality signal generating means). Furthermore, if the determination result in step S6 is No, it is determined to be normal and the program is terminated.

Next, the operation of this embodiment will be explained.

During warm-up of the engine 2, in order to promote the atomization of the fuel from the fuel injection valve 5 and improve the ignitability of the air-fuel mixture in the combustion chamber 3, if the engine cooling water temperature is less than 40'C, The electromagnetic valve 9 is energized to open the auxiliary intake passage 6, and auxiliary air is supplied around the nozzle of each fuel injection valve 5.

In the control circuit 8, in order to detect an abnormality when the branch passage 6a of the auxiliary intake passage 6 is clogged, the following operations are performed after the warm-up operation is completed (normally in the region where the solenoid valve 9 is closed). .

When the engine cooling water temperature is 80° C. or higher, the engine is in a neutral and idling state, and the engine speed Ne is stable, the electromagnetic valve 9 is energized for a predetermined second. As a result, the sub-intake passage 6 is opened, and the branch passage 6
Since auxiliary air is supplied around the nozzle of each fuel injection valve 5 via a, the engine speed Ne increases.

At this time, for example, if one of the branch passages 6a is clogged, auxiliary air will no longer be supplied to that extent, so that an increase in the engine speed Ne can be suppressed.

Therefore, if the maximum engine speed maxNe during the predetermined second during which the auxiliary intake passage 6 is opened is equal to or higher than the preset value α, it is determined that there is no abnormality and the warning lamp does not illuminate. However, the maximum engine speed n+ax
When Ne is less than the set value α, it is determined that an abnormality due to clogging has occurred in the branch passage 6a as described above, an abnormality signal is generated, and the alarm lamp is energized.

In this way, if it is determined that an abnormality has occurred in the device 1, it is possible to generate an abnormality signal and turn on the alarm lamp to notify the user of this fact, so that the abnormality in the device 1 can be detected early. can be solved. As a result, an increase in harmful components in the exhaust gas can be prevented.

In addition to turning on the alarm lamp, from next time onwards, when energizing the solenoid valve 9, the throttle valve 7 will also be turned on at the same time.
Deterioration of the exhaust gas components may be prevented by driving the engine a little more or by feeding auxiliary air from another bypass passage (not shown).

In the above embodiment, in order to promote atomization of fuel from the fuel injection valve 5 during warm-up of the engine 2, the solenoid valve 9 is energized when the engine cooling water temperature is less than 40°C. However, it is not necessary to limit the temperature to 40°C. Alternatively, the electromagnetic valve 9 may be energized at all times, and only when an abnormality is detected, the energization to the electromagnetic valve 9 may be stopped for a predetermined period of time. At this time, the difference between the engine rotation speed when the solenoid valve 9 is energized and the engine rotation speed when the energization is stopped is determined, and when the value is less than a set value, it is determined that there is an abnormality.

In addition, although it was determined that an abnormality occurred when the maximum engine speed maxN e was less than the set value α, as described above, the difference between the engine speed when the solenoid valve 9 is energized and the engine speed when the solenoid valve 9 is not energized is calculated. , it may be determined that there is an abnormality when the value is less than a set value.

The operation of the control circuit 8 when detecting an abnormality causes the cooling water temperature to rise to 8.
Although the determination was made as to whether the temperature was 0° C. or higher, this was done in consideration of the influence of the air valve provided to bypass the throttle valve 7, and it is not necessarily necessary to limit the temperature to 80° C.

When detecting an abnormality caused by the control circuit 8, the engine rotation sensor 11 that detects the engine rotation speed is shown as the detection means of the present invention to be compared with the set value α. Engine 2 such as torque
The operating state of the controller may be detected and compared with the set value.

Instead of a warning lamp, a buzzer may sound or text or pictures may be displayed to notify the user of an abnormality.

[Brief explanation of drawings]

1 and 2 show an embodiment of the present invention,
Figure 1 is an overall schematic diagram of the auxiliary air control device for the fuel injection valve.
FIG. 2 is a flowchart showing the operation of the control circuit. In the figure: 1... Fuel injection valve auxiliary air control device 2... Engine (internal combustion engine) 3... Combustion chamber 4... Main intake passage 5... Fuel injection valve 6... Sub-intake passage 7...Throttle valve 8...Control circuit (control means) 9...Solenoid valve (opening/closing means)

Claims (1)

[Scope of Claims] 1) (a) A main intake passage that communicates with the combustion chamber of the internal combustion engine and is provided with a throttle valve therein; (b) A main intake passage that is provided in the main intake passage downstream of the throttle valve. a fuel injection valve; (c) a sub-intake passage for supplying auxiliary air around the nozzle of the fuel injection valve, bypassing the throttle valve; and (d) a sub-intake passage interposed in the sub-intake passage; an opening/closing means for opening and closing the auxiliary intake passage; (e) a control means comprising a detection means for detecting the operating state of the internal combustion engine, and controlling opening/closing of the opening/closing means according to a detected value of the detection means; (f) ) a switching means for forcibly switching between an opening operation and a closing operation of the opening/closing means when the internal combustion engine is in a specific operating state; An auxiliary air control device for a fuel injection valve, comprising an abnormality signal generation means for determining the abnormality signal and generating an abnormality signal.