JPH06317231A - Electromagnetic fuel injection valve and fuel injection device - Google Patents

Abstract

(57) [Summary] [Object] To provide an electromagnetic fuel injection valve having a relatively simple structure and capable of sufficiently atomizing fuel. [Structure] Gas supply port 10 is provided in a fuel passage from fuel supply port 1.
A gas passage is provided so that bubbles are mixed in the fuel injected from the fuel injection hole 9. This bubble
When the fuel is injected from the fuel injection hole 9 into the intake pipe, it expands and bursts, sufficiently atomizing the fuel. [Effect] The fuel can be effectively atomized with a simple structure, and the combustion state of the engine can be sufficiently improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic fuel injection valve and a fuel injection device installed in an intake passage of an internal combustion engine for injecting fuel into intake air to obtain an air-fuel mixture. The present invention relates to an electromagnetic fuel injection valve and a fuel injection device suitable for an engine.

[0002]

2. Description of the Related Art In order to obtain a good air-fuel mixture and improve a combustion state in an engine of an intake pipe fuel injection system, it is a condition that the injected fuel is sufficiently atomized. Therefore, various proposals have hitherto been made on a method of atomizing the injected fuel by using a gas, for example, Japanese Patent Laid-Open No.
Japanese Patent No. 159453 discloses a technique in which air is collided with fuel injected from a nozzle to atomize the fuel.

On the other hand, although nothing is disclosed about atomization of the fuel injected into the intake pipe, the technique of injecting the fuel into the combustion chamber of the engine by air is disclosed in, for example, Japanese Patent Publication No. Sho 63-63. -500319.

[0004]

The above-mentioned prior art can sufficiently achieve atomization of fuel, but it cannot be said that sufficient consideration is given to the point of suppressing the complication of the structure. Since the structure of the portion where the gas collides with the fuel is complicated and precision is required, there is a problem that the cost increases. An object of the present invention is to provide a fuel injection valve and a fuel injection device capable of sufficiently obtaining atomization of fuel with a relatively simple structure.

[0005]

SUMMARY OF THE INVENTION The above object is to provide a gas supply passage upstream of an injection amount measuring mechanism including at least one of a valve device and a fuel injection hole, and when the valve is opened, a fuel mixed with gas is mixed. Are supplied to the fuel injection holes.

[0006]

When the fuel injection valve is opened, the fuel flows toward the fuel injection hole. At this time, the gas supply passage works so that the gas is mixed with the fuel. The gas mixed with the fuel exists in the fuel as small bubbles due to the pressure of the fuel, but since the pressure drop of the fuel is relatively small on the upstream side of the valve device, the bubbles present in the fuel are , Still small. The pressure of the fuel drops between the valve device and the fuel injection hole, and the bubbles existing in the fuel at this time increase as the pressure of the fuel decreases. Then, when the fuel is injected from the fuel injection hole, the pressure of the fuel is greatly reduced, and as a result, the size of the bubble is maximized, and then the bubble is ruptured and mixed with the air in the intake pipe to which the fuel is injected.

In this process, the fuel is made into a thin film according to the expansion of the bubbles, and thereafter, the kinetic energy when the bubbles burst is received, so that the fuel is sufficiently atomized.

Therefore, atomization of the injected fuel can be effectively obtained with a relatively simple structure in which the gas supply passage is provided on the upstream side of the injection amount measuring mechanism.

[0009]

The present invention will now be described in detail with reference to the illustrated embodiments. FIG. 1 is a first embodiment of an electromagnetic fuel injection valve according to the present invention, in which the entire fuel injection valve is represented by A. In the drawing, 1 is a supply port, and fuel is from a fuel supply passage to this supply port 1. It is supplied to the inside of the injection valve through the nozzle and always reaches the nozzle portion 2.

A valve body 3 is provided inside the nozzle portion 2, and a valve body tip portion 4 which is the tip thereof is normally pressed by a spring 5 against a valve seat 6 to close the valve. However, when the drive signal is supplied to the solenoid 7, the iron core inside is excited, so that the plunger connected to the valve body 3 is attracted and the valve body 3 separates from the valve seat 6. The fuel is injected from the fuel injection hole 9.

At this time, the moving distance of the valve body 3 is determined by the contact of the valve body side positioning member 11 with the fixed side positioning member 12. On the other hand, 10 is a gas supply port of the gas supply passage, and a predetermined gas such as air is constantly supplied from the gas supply source at a predetermined pressure. Therefore, the gas is supplied to the inside of the injection valve through the supply port 1. The fuel is mixed with gas.

FIG. 3 shows an embodiment of an electromagnetic fuel injection system for an internal combustion engine using the electromagnetic fuel injection valve A according to the present invention shown in FIG. 1. This fuel injection valve A is an intake valve of the engine 13. It is attached to the intake pipe 17 toward 14, and is controlled by the control unit 22. The fuel is pressurized from the fuel tank 20 by the fuel pump 21 and is supplied to the fuel supply port 1 of the fuel injection valve A, while the gas mixed with the fuel is supplied from the pressure supply source 25 to the auxiliary flow meter 24. It is supplied to the gas supply port 10 of the fuel injection valve A through the air damper 26.

The intake air supplied to the engine 13 is adjusted by the throttle 19 and measured by the main flow meter 23.
When the gas supplied to the fuel injection valve A is air, the sum of the air amount measured by the auxiliary flow meter 24 and the air amount measured by the main flow meter 23 is the intake air amount supplied to the engine 13. Become. The pressure of the gas supplied from the pressure supply source 25 to the fuel injection valve A is controlled so as to be higher than the pressure of the fuel when mixed with the fuel when the fuel is injected, but the fuel is injected. When not performed, the pressures of the gas and the fuel are controlled to be equal so that backflow does not occur in either the gas or the fuel.

Next, the operation of this embodiment will be described. Now, from the control unit 22 to the fuel injection valve A
When the drive signal is supplied to the valve body 3, the valve body 3 separates from the valve seat 6, so that fuel is injected from the fuel injection hole 9. At this time, the gas supplied from the gas supply port 10 is mixed with the fuel, and the mixed gas exists in the fuel as sufficiently small bubbles due to the pressure of the fuel.

Further, on the upstream side of the valve seat 6, even if the valve device is opened, the pressure drop of the fuel is relatively small, so that the bubbles existing in the fuel remain small. As the fuel is injected, the pressure of the fuel drops from the valve seat 6 to the fuel injection hole 9. At this time, the size of the bubbles existing in the fuel decreases the pressure of the fuel. Grows according to.

Then, when the fuel is injected from the fuel injection hole 9, at this time, the pressure of the fuel suddenly drops, and as a result, the size of the bubble reaches the maximum value as shown in FIG.
Eventually, it bursts like a soap bubble and mixes with the air in the intake pipe 17 where the fuel is injected.

In this process, the fuel is first made into a thin film as the bubbles expand and expand, and then the bubbles are blown away by the kinetic energy when the bubbles burst and mix with the air in the intake pipe 17, and they are atomized. It

Therefore, according to this embodiment, the fuel is made into extremely fine particles at the time of injection, so that sufficient atomization can be easily and surely obtained, and combustion of the engine can be performed. The condition can be greatly improved.

Next, another embodiment of the present invention will be described. FIG. 4 shows a second embodiment of the present invention.
Is a fuel swirling member (swirler), which is provided in the vicinity of the valve body tip portion 4, and accordingly, the valve seat 6 of the valve body tip portion 4 is provided.
The shape of the portion in contact with is spherical, and other configurations are the same as those of the embodiment of FIG.

According to the embodiment of FIG. 4, during fuel injection,
Similar to the embodiment shown in FIG. 1, fine particles of fuel can be obtained by mixing gas with fuel, and as shown in FIG.
Since the fuel swirling member 8 imparts a fuel atomization effect by imparting a swirling force to the fuel spray injected from the fuel injection holes 9, atomization is further promoted and a better combustion state can be obtained. .

Next, FIG. 6 shows a third embodiment of the present invention.
In the figure, 27 is a venturi portion, and other configurations are the same as those of the embodiment of FIG. The venturi portion 27 is
It is formed in a portion of a passage for supplying fuel from the fuel supply port 1 into the fuel injection valve A, where a gas supply passage from the gas supply port 10 joins.

Since the venturi portion 27 is provided, the pressure of the gas supplied to the gas supply port 10 is equal to the pressure of the fuel supplied to the fuel supply port 1 in this embodiment. Controlled.

Next, the operation of this embodiment will be described. When fuel is injected, the fuel flows through the venturi portion 27. As a result, the fuel pressure in the venturi portion 27 is higher than the fuel supply pressure. descend. On the other hand, since the gas supply pressure is controlled to be equal to the fuel supply pressure, the fuel pressure of the venturi portion 27 becomes lower than the gas supply pressure, and as a result, when the fuel is injected, the gas is It is sucked into the fuel of the venturi section 27,
Since it will be mixed with the fuel stream and the pressure of the gas and the fuel will be equal when the fuel is not injected, no backflow will occur in either the gas or the fuel.

Therefore, according to the embodiment shown in FIG.
In addition to obtaining the same fuel atomization as in the above embodiment, the venturi portion 27 is provided in the passage portion from the gas supply port 10 to control the fuel supply pressure and the gas supply pressure without impairing the atomization of the fuel. Can be simplified.

In the embodiment of FIG. 6, the venturi portion 27 is provided in the embodiment having the fuel swirl member 8 of FIG. 4, but the fuel swirl member is not provided as in the embodiment of FIG. A venturi portion may be provided in the electromagnetic fuel injection valve.

By the way, in the above-mentioned embodiments, air has been described as an example of the predetermined gas to be mixed with the fuel. However, the present invention is not limited to air, and any gas such as, for example, blow-by gas of an engine may be used. Needless to say, it can be implemented by using.

[0027]

According to the present invention, with a relatively simple structure,
The fuel injected from the fuel injection holes can be effectively atomized, and the combustion state of the engine can be greatly improved at low cost.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of an electromagnetic fuel injection valve according to the present invention.

FIG. 2 is an enlarged view of a nozzle portion for explaining a fuel atomization operation according to the first embodiment of the present invention.

FIG. 3 is a configuration diagram showing an embodiment of a fuel injection device using a fuel injection valve according to the present invention.

FIG. 4 is a longitudinal sectional view showing a second embodiment of the fuel injection valve according to the present invention.

FIG. 5 is an enlarged view of a nozzle portion for explaining the fuel atomization operation according to the second embodiment of the present invention.

FIG. 6 is a longitudinal sectional view showing a third embodiment of the fuel injection valve according to the present invention.

[Explanation of symbols]

 1 Fuel Supply Port 2 Nozzle Part 3 Valve Body 4 Valve Body Tip Part 5 Spring 6 Valve Seat 7 Solenoid 8 Fuel Swirling Member 9 Fuel Injection Hole 10 Gas Supply Port 11 Valve Body Side Positioning Member 12 Fixed Side Positioning Member 13 Engine 14 Intake Valve 15 Exhaust valve 16 Combustion chamber 17 Intake pipe 18 Exhaust pipe 19 Throttle 20 Fuel tank 21 Fuel pump 22 Control unit 23 Main flow meter 24 Sub flow meter 25 Pressure supply source 26 Air damper 27 Venturi part

Front Page Continuation (72) Inventor Atsushi Sekine 2477 Kashima Yatsu Kashima Yatsu, Katsuta City, Ibaraki Prefecture 3 Hitachi Automotive Engineering Co., Ltd.

Claims (5)

[Claims] 1. An electromagnetic fuel injection valve of a system in which an injection amount of fuel pressurized and injected from a fuel injection hole is controlled by opening / closing time of an electromagnetically driven valve device, and at least one of the valve device and the fuel injection hole. An electromagnetic fuel injection valve, characterized in that a gas supply passage is provided on the upstream side of the injection amount measuring mechanism consisting of, and the fuel mixed with the gas is supplied to the fuel injection hole. 2. The electromagnetic fuel injection valve according to claim 1, wherein the gas supplied from the gas supply passage and mixed with the fuel is air. 3. The electromagnetic fuel injection valve according to claim 1 or 2, characterized in that a fuel swirl member for imparting swirl force to the supplied fuel is provided upstream of the valve device. 4. The electromagnetic fuel injection valve according to claim 1 or 2, wherein the shape of the fuel passage at the portion where the gas supply passage merges with the fuel passage is formed into a venturi shape. . 5. A fuel injection device for an internal combustion engine, characterized in that fuel injection is performed using any one of the electromagnetic fuel injection valves according to the inventions of claims 1 to 4.