JP2529082Y2 - Multi-hole injector - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a porous injector having injection holes directed toward a plurality of intake ports provided for each cylinder in a vehicle engine.

[0002]

2. Description of the Related Art As a prior art of this kind, for example, a two-hole injector disclosed in Japanese Utility Model Laid-Open Publication No. 61-57166 can be mentioned. In this configuration, assist air is supplied to the upstream side of the branch point between the two injection holes of the injector. For example, when air is supplied to the combustion chamber only from one intake port of each cylinder at the time of low-load operation of the engine, the assist air supplies fuel injected from an injection hole of an injector to the one intake port. It has the function of deflecting the light only toward.

[0003]

In the technique disclosed in the above publication, assist air is supplied upstream of the branch point between the two injection holes, that is, at a location where fuel has not yet been atomized. Therefore, although this assist air has the function of deflecting the injected fuel as described above, there remains a problem in realizing atomization of the fuel.

[0004] The technical problem of the present invention is to provide a porous injector which can effectively realize atomization of injected fuel.

[0005]

SUMMARY OF THE INVENTION The present invention is directed to a multi-hole engine having a plurality of injection ports, each of which is installed in an engine having a plurality of intake ports for each cylinder and directed toward each intake port of each cylinder. a formula injector, each injection hole is constituted by branching from one jet passage, respectively communicated with the air supply passage for supplying a Shisutoea to the respective injection holes of the downstream side from the branch point, moreover Make sure that the intersection angle between each injection hole and the air supply passage is set to a substantially right angle.
Features .

[0006]

According to the present invention, each jet hole is formed from one jet passage.
To the fuel that flows into the
The air is blown from almost right angles. For this reason,
Assist air is applied to the liquid film of fuel flowing through each injection hole.
The air stream violently collides to disperse this liquid film
And the atomization of the fuel is promoted. In addition, atomization of fuel
Is repelled by the liquid film of fuel flowing along the inner wall surface of the injection hole.
This liquid film is scattered by colliding the air flow of the strike air.
It is thought that
The force to disperse the liquid film is to apply airflow to this liquid film.
Largest fuel particle when impacted from right angle
The effect of conversion is also large.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. In the following embodiments, the present invention is applied to a two-hole injector used for a vehicle engine.
FIG. 3 is a sectional view showing a relevant portion of one cylinder 50 of the engine and the intake manifold 56, and FIG. 4 is a plan sectional view thereof. 3 and 4, the cylinder 50 has two intake ports 52 and one exhaust port 54. The intake air passage in the intake manifold 56 communicating with both intake ports 52 includes:
A well-known throttle valve 58 is incorporated so as to control opening and closing of the passage. A two-hole injector 10 for individually injecting fuel toward both intake ports 52 of the cylinder 50 is attached to a wall of the intake manifold 56.

FIG. 1 is a sectional view of the injector 10, and FIG. 2 is an enlarged sectional view of a part of FIG.
First, as apparent from FIG. 1, a solenoid coil 12, a hollow core 14, and an armature 24 are incorporated in a casing 11 of the injector 10. When the solenoid coil 12 is energized, a magnetic circuit is formed in the core 14, the armature 24 and a part of the casing 11. Due to the magnetic force at this time, the armature 24 slides upward by a predetermined stroke from the state shown in the drawing against the elastic force of the valve spring 28 together with the valve 26 described later. Further, inside the casing 11, below the armature 24 in the drawing,
A valve housing 16 is incorporated. The inside of the valve housing 16 is formed in a hollow concentric with the hollow portions of the core 14 and the armature 24. As shown in FIG. 2, a nozzle 18 communicating with the inside of the valve housing 16 is opened at the lower end of the valve housing 16, and a valve seat 17 is formed inside the nozzle 18.

Further, a hollow valve 26 is incorporated in the valve housing 16. The valve 26 is fixed to the armature 24 and is slidable with the armature 24 as described above. A ball 26a is fixed to the distal end (the lower end in the drawing) of the valve 26. The ball 26a is pressed against the valve seat 17 of the valve housing 16 by the elastic force of the valve spring 28 to close the nozzle 18. In FIG. 1, the core 14
A strainer 22 is attached to the inside of the upper end of the fuel injector, and a hollow portion between the strainer 22 and the nozzle 18 forms a fuel passage 20 of the injector 10.

An adapter 30 is fixed to the distal end (the lower end in the drawing) of the valve housing 16 by caulking the casing 11. A jet passage 32 communicating with the nozzle 18 of the valve housing 16 is formed inside the adapter 30. Further, two injection holes 36 which are continuous with the jet flow passage 32 and are branched by a splitter 34 are formed inside the adapter 30. These two injection holes 36 are respectively opened at the end face of the adapter 30. The openings of the two injection holes 36 are directed toward the two intake ports 52 of the cylinder 50 shown in FIGS. 3 and 4, respectively.

The adapter 30 is provided with air supply passages 38 for supplying assist air, which penetrate from the outer peripheral surface to the two injection holes 36. That is, these two air supply paths 38 communicate with the two injection holes 36 on the downstream side of the branch point of the splitter 34. Moreover, the intersection angle θ between the two injection holes 36 and the air supply passage 38 is set to a right angle (90 °) (see FIG. 2). An air adapter 40 is attached to the outer periphery of the distal end portion (the lower end portion in the drawing) of the injector 10 including the adapter 30 and a part of the casing 11. The air adapter 40 is formed in a cylindrical shape, and is airtightly assembled to the casing 11 and the adapter 30 with air seals 42 and 44 interposed therebetween. Thus, an airtight space 46 communicating with the air supply passages 38 is formed inside the air adapter 40. The air adapter 40 is provided with a pipe-shaped connection port 48 which communicates with an internal space 46 and extends outward. As shown in FIG. 3, the connection port 48 communicates with the upstream side of the throttle valve 58 in the intake manifold 56 by an air pipe 60.

In the injector 10 having the above-described structure, the valve 26 is operated in the upward direction in FIGS. 1 and 2 by the action of the magnetic force generated by the energization of the solenoid coil 12, and the nozzle 18 is opened as described above. .
Therefore, the fuel supplied to the fuel passage 20 is ejected from the nozzle 18 into the jet passage 32, and collides with the slope 35 of the splitter 34, which is a branch point of the two injection holes 36, and is atomized. At the same time, the air is supplied into the two injection holes 36 through the air supply passage 38 due to the pressure difference between the two and the injection manifold 36. That is, after the fuel collides with the slope 35 of the splitter 34 and is atomized, assist air is supplied into both the injection holes 36. Thereby, the fuel is effectively atomized and injected from both the injection holes 36 toward both the intake ports 52 of the cylinder 50 as shown in FIGS. 3 and 4.

In an experimental example in which 145 cc of fuel was jetted from the nozzle 18 at a rate of 145 cc / min, atomization of the fuel having a particle size of about 50 μ was realized by supplying assist air to each of the two injection holes 36. .

Further, since the intersection angle θ between the injection holes 36 and the air supply passage 38 is set to 90 °, the assist air is supplied to the liquid film of the fuel flowing through each injection hole 36.
The air flow collides vigorously to disperse the liquid film, thereby promoting the atomization of the fuel. This is clear from the experimental results based on the relationship between the intersection angle θ and the particle size of the fuel shown in FIG. This experiment was performed when the assist air differential pressure was 200 mmHg and 500 mmHg. In any case, the particle diameter of the fuel is smallest when the intersection angle θ is 90 °, and about 100 μm when the pressure difference is 200 mmHg.
And a particle diameter of about 25 μm when the differential pressure is 500 mmHg. The differential pressure of the assist air is a difference between the air pressure supplied from the air supply passage 38 and the air pressure (atmospheric pressure) upstream of the throttle valve 58 in the intake manifold 56. And differential pressure 200mmHg
Is a state where the vehicle is traveling at a substantially constant speed, and the differential pressure is 500
mmHg is an idling state. Note that the flow through each injection hole 36
Assist air is blown at right angles to the fuel
Fuel is likely to flow backward due to the
The hole 36 does not flow all the way through the hole.
Each air supply passage 38 for cyst air is provided by an ejection port of the ejection hole 36.
Is located far enough from
Even if a slight backflow of fuel occurs due to air blowing,
There is no risk of adversely affecting the performance as an injector.
No. In addition, the intersection angle θ is manufactured with the aim of 90 °.
However, there is a variation of about ± 5 ° due to manufacturing errors.
Is inevitable. That is, the intersection angle θ = 90 °
What is a practical
Pointing to the corner. And within this range of error,
When the difference angle θ is set to exactly 90 °, the fuel
Almost the same value as the particle size value is obtained.

Although the embodiment of the present invention has been described with reference to the drawings, the present invention is not limited to this embodiment but includes various embodiments. For example, the assist air guided from the intake manifold 56 to the air supply passage 38 may be replaced with compressed air using a compressor or the like. Further, the number of intake ports 52 of each cylinder 50 and the number of injection holes 36 of the injector 10 may be three or more.

[0016]

[Effects of the Invention] The present invention is based on the fact that each jet hole is
Assist air is almost directly
Fuel that flows through each injection hole because it is blown from the corner
Air flow of assist air vigorously collides with the liquid film of
This liquid film is scattered, and the atomization of fuel is promoted.
You.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an injector used in a vehicle engine.

FIG. 2 is an enlarged sectional view of a part of FIG.

FIG. 3 is a cross-sectional view showing a relevant portion of one cylinder of an engine and an intake manifold.

FIG. 4 is a plan view of FIG. 3;

FIG. 5 is a characteristic diagram showing an experimental result based on a relationship between an intersection angle θ and a particle diameter of a fuel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Injector 32 Jet flow path 36 Injection hole 38 Air supply path 50 Cylinder 52 Intake port θ Crossing angle

Claims (1)

(57) [Scope of request for utility model registration] 1. A multi-hole injector provided in an engine having a plurality of intake ports for each cylinder and having a plurality of injection holes directed toward the respective intake ports for each cylinder, injection hole is constituted by branching from one jet passage, respectively communicated with the air supply passage a cis <br/> Toea for supplying to the respective injection holes of the downstream side from the branch point, yet each injection hole Characterized in that the crossing angle between the air injector and the air supply passage is set substantially at right angles.