JP2000080970A - Fluid injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a good flat fan-like spray pattern, to suppress the sticking of a deposit to an injection hole and to facilitate the manufacturing of an injection valve. SOLUTION: A fuel injection valve 1 used for a direct injection gasoline engine is provided with a guide 2 provided inside an injection valve body 10 to hold a valve element 3, an orifice member 4 disposed in the tip of the injection valve body 10 and having an injection hole 41 opened to be extended in the radial direction of the injection valve body 10, and a plurality of opposing fuel passage 24 formed to be communicated with the injection hole 41 via the valve element 3 between the injection valve body 10 and the guide 2 and to apply a distribution pressing force expanded in the diameter direction of the injection hole orthogonal to a valve element axial direction by clashing the flow of fuel flowing along the tip part of the valve element 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid injection valve for supplying a liquid fuel such as gasoline or the like as a spray.

[0002]

2. Description of the Related Art Conventionally, as a fluid injection valve, for example, a fuel injection valve (JP-A-3-78562, JP-A-9-158736).
As shown in FIG. 9, by forming a slit-shaped fuel injection hole O in the diameter direction at the small-diameter tip end portion T of the valve body B, the fuel spray pattern is made into a flat fan shape, and the whole spray comes into contact with air. It was easy to obtain a relatively homogeneous spray.

[0003]

In the above-mentioned conventional fuel injection valve, since both the spray angle and the injection amount are defined by the slit-shaped injection holes O, if one of them is adjusted, the other also changes accordingly. However, there is a problem that adjustment for satisfying both is difficult.

Further, in the above-mentioned conventional fuel injection valve, since the slit-shaped injection hole O is formed at the small-diameter tip end portion T of the valve body B, it is difficult to process the slit-shaped injection hole O, and the productivity is increased. In addition, the size of the slit-shaped injection hole O has a great influence on the spray shape, so that the required accuracy for processing is severe and there is a problem that it is not suitable for mass production.

Further, in the above conventional fuel injection valve, the fuel to be injected flows into the wide slit-shaped injection hole O after passing through the narrow space S. Since only the central portion flows, fuel stays at both ends in the longitudinal direction of the slit-shaped injection hole O,
This stagnant fuel becomes a deposit and accumulates in the injection hole O, and the deposited deposit changes the shape of the spray.

Accordingly, the present inventor has proposed an injection hole formed at the tip of the injection valve, a fluid supply passage provided inside the injection valve body and supplying fluid upstream of the injection hole, an upstream of the injection hole and a fluid supply passage. And a needle that opens and closes a communication passage between the injection passage and the needle, the cross-sectional area of the communication passage near one direction orthogonal to the axis of the injection valve is larger than the cross-sectional area of the communication passage in other regions. By reducing the size or by not providing the communication passage, the fuel flow from the communication passage is collided, and a flow force that spreads in a direction orthogonal to the collision site is given, and a fan-shaped fan is formed from the injection hole. Focusing on the technical idea of the present invention of spraying a fluid spray that spreads in form, as a result of further research and development, a good flat fan-shaped spray pattern was realized, and adhesion of deposits to the spray holes was suppressed, Injection valve The completed the present invention to achieve the object of facilitating.

[0007]

According to a first aspect of the present invention, there is provided a fluid injection valve provided at an injection hole formed at a tip of the injection valve and inside the injection valve main body. In a fluid injection valve provided with a fluid supply passage for supplying fluid upstream of the hole and a needle for opening and closing a communication passage between the upstream of the injection hole and the fluid supply passage, a fluid injection valve is provided near one direction substantially orthogonal to the axis of the injection valve. , The cross-sectional area of the communication passage is smaller than the cross-sectional area of the communication passage in another region, or the communication passage is not provided.

(Function of the Invention) The fluid injection valve of the present invention having the above-described structure collides the flow of the fluid from the communication passage, and imparts a flow force expanding in a direction orthogonal to the collision site, thereby providing This sprays a fluid spray that spreads in a fan shape from the injection hole.

That is, the fluid injection valve of the present invention suppresses the inflow of fluid to the upstream of the injection hole by increasing the resistance of the fluid passage in the direction in which the fluid spray is desired to be flattened or by not providing the fluid passage itself. Thereby, the fluid inflow in the direction in which the fluid spray is desired to be flattened is suppressed and extremely eliminated. Then, this direction is the direction in which the fluid flowing from the fluid passage has the smallest resistance, and flows positively in this direction, so that sufficient fluid is supplied in the flat direction.

[0010]

According to the fluid injection valve of the present invention having the above-described effect, a fluid spray which spreads in a fan-like form from the above-mentioned injection hole is realized, and a good flat fan-like spray pattern is realized.
This has the effect of suppressing deposition of deposits on the injection holes and facilitating the manufacture of the injection valve.

According to another invention (a second invention according to claim 2), in the fluid injection valve according to the first invention, as shown in FIG. 1, the communication passage is formed in one direction orthogonal to an axis of the injection valve. It is characterized by being provided only on the vicinity.

Another invention (third invention according to claim 3) is the injection valve according to the first invention, wherein the injection valve shown in FIGS.
As shown in (1), the communication path is not provided only in the vicinity of one direction orthogonal to the axis of the injection valve.

According to a fourth aspect of the present invention, there is provided an injection valve according to any one of the first to third aspects, wherein the injection hole has a flat cross-sectional slit shape, and The slit-shaped longitudinal direction is positioned substantially parallel to one direction orthogonal to the axis of the injection valve having a small cross-sectional area or having no communication passage.

The fluid injection valves of the second to fourth inventions have substantially the same functions and effects as the fluid injection valve of the first invention.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the drawings.

(Embodiment) A fuel injection valve as a fluid injection valve according to this embodiment is a fuel injection valve 1 for use in a direct injection gasoline engine, and as shown in FIGS. A guide 2 provided in the interior of the injection valve 10 for holding the valve body 3 and an orifice member provided at the tip of the injection valve main body 10 and having an injection hole 41 formed in the injection valve main body 10 and extending in the radial direction; 4, the injection hole 41 between the injection valve body 10 and the guide 2 via the valve body 3.
A plurality of opposing members that are formed so as to communicate with each other and that impinge a flow of fuel flowing along the distal end portion of the valve body 3 to impart a flow force that expands in the diameter direction of the injection hole orthogonal to the valve body axis direction. And a fuel passage 24.

The fuel injection valve according to the present embodiment is provided in an internal combustion engine of a type in which liquid fuel such as gasoline is directly injected into a cylinder constituting a combustion chamber.

As shown in FIG. 4, the fuel injection valve 1 is constituted by an injection valve body 10 having a hollow cylindrical body, and a conical surface is formed on an inner wall of a lower end portion constituting a front end portion of the injection valve body 1. 11 is formed, and a circular opening 12 is formed in the center of the lower end.

As shown in FIGS. 4 to 7, the guide 2 has an outer diameter outer wall 21 inserted and fitted into the inner wall 13 of the injection valve main body 10, and the valve element is reciprocally movable. Is formed by a hollow cylindrical body 20 having an inner peripheral wall 22 interposed therebetween, and a conical surface 23 in contact with the conical surface 11 of the injection valve body 10 is formed at a lower end.

As shown in FIG. 5, the outer peripheral wall 21 of the guide 2 is formed with an arcuate shape on both sides to form the injection valve main body 1.
Two vertical fuel passages 25 are formed between the inner peripheral wall 13 and the inner peripheral wall 13, and two fuel passages 24 are formed in a straight line facing the conical surface 23 in communication with the vertical fuel passage 25. ing.

The valve body 3 is reciprocally inserted into the inner peripheral wall 22 of the guide 2 and has a tip with a different angle.
Needle 3 with tip 31 having three conical surfaces
0.

That is, the tip portion 31 of the needle 30
Are arranged in a line in a straight line,
Of the fuel passages 2
The distal end portion 31 of the needle 30 is disposed so as to be located on the extension line of the conical surface 23 in the inclined direction.

The orifice member 4 is shown in FIGS.
As shown in FIG. 2, the fuel injection valve body 10 is formed of a disk-shaped member attached to the lower end of the injection valve body 10, and the two fuel passages 24 are formed in a straight line on the conical surface 23 of the guide 2.
A slit-shaped injection hole 41 whose longitudinal direction is perpendicular to the slit is formed.

The slit-shaped injection hole 41 is set to be smaller than the diameter of the circular opening 12 formed at the center of the lower end of the injection valve main body 10 and the tip of the valve body 3 is formed. A space 5 having a predetermined cross-sectional area and volume is formed between the portion 31 and the orifice member 4.

The cross-sectional area of the space 5 and the cross-sectional area of the circular opening 12 formed at the center of the lower end of the injection valve main body 1 are set to be sufficiently larger than the opening area of the slit-shaped injection hole 41 of the orifice member 4. Since the fuel from the fuel passage 24 is most narrowed in the slit-shaped injection holes 41, the fuel is configured to pass uniformly in the longitudinal direction of the slit-shaped injection holes 41. .

In the fuel injection valve of the present embodiment having the above-described structure, fuel is supplied from the upper portion of the injection valve and the fuel injection valve is formed between the guide 2 as a flow path guide and the injection valve body 10. It is guided along the vertical fuel passage 25 to the tip of the injection valve.

That is, as shown in FIG. 5, the outer peripheral walls 21 on both sides in the left-right direction of the flow path guide 2 are cut in an arc shape, and the fuel guide is formed by a flat surface on both sides from the center of the two cut surfaces. A passage 24 is formed.

As shown in FIG. 4, the flow guide 2 is inserted into the distal end of the injection valve body 10, and the conical surface 23 at the lower end of the flow guide 2 and the conical surface 11 inside the distal end of the injection valve. Are in close contact with each other, so that the fuel guided to the tip of the injection valve body 10
4 and is introduced into the space 5 inside the tip of the injector.

Since the fuel passages 24 are formed in a straight line so as to face each other, the fuel flowing out of the fuel passages 24 flows along the tip of the valve body 3 and collides with the fuel. Along the outer peripheral wall of the tapered distal end portion 31 of the body 3, it branches and spreads left and right and downward, and spreads in the longitudinal direction of the injection hole 41 orthogonal to the valve body axial direction formed in the orifice member 4.

In the injection valve according to the present embodiment, the injection hole 4
Since 1 is a slit-shaped elongated hole, the colliding fuel liquid spreads in the longitudinal direction of the injection hole 7 and is sprayed as a fan-shaped spray.

In the fuel injection valve of the present embodiment having the above-described action, the flow of the fuel flowing along the outer peripheral wall of the tapered distal end portion 31 of the valve body 3 is collided by the plurality of opposed fuel passages 24, and the orifice By applying a flow force expanding in the diameter direction of the injection hole orthogonal to the axial direction of the valve body formed in the member, the fuel spray is sprayed from the injection hole into a fan-like form. This has the effect of realizing a pattern.

That is, the fuel passage 24 allows the fuel to flow as two flows opposing each other along the conical surface of the needle 30 having the conical tip portion 31. An orifice member 4 as a thin plate orifice member attached to the tip of a body as the injection valve body 10, which is formed so as to collide near the vertex of the conical surface and slides with the needle 30, is elongated in the center. Since the injection hole 41 of the hole is open,
Since the fuel is spread in a fan shape, a good flat fan-shaped spray pattern is realized.

Further, the fuel injection valve of this embodiment allows the fuel to pass uniformly in the longitudinal direction of the slit-shaped injection hole 41 in order to realize a good flat fan-shaped spray pattern. In addition to suppressing the adhesion of deposits, fuel stagnates at both ends in the longitudinal direction of the slit as in the past, and the accumulated fuel becomes a deposit and accumulates in the injection hole. This has the effect of eliminating the problem that changes occur.

That is, the cross-sectional area of the space 5 and the cross-sectional area of the circular opening 12 formed at the center of the lower end of the injection valve body 1 are sufficiently larger than the opening area of the slit-shaped injection hole 41 of the orifice member 4. Since the fuel injection from the fuel passage 24 is most narrowed in the slit-shaped injection holes 41, the fuel uniformly passes in the longitudinal direction of the slit-shaped injection holes 41. It suppresses the adhesion of the deposit to the holes, and suppresses the change in the shape of the spray due to the deposited deposit.

Further, in the fuel injection valve of the present embodiment, since the injection hole is a slit-shaped elongated hole having a simple shape, there is an effect that the processing is easier than a conventional slit nozzle. .

In the fuel injection valve of the present embodiment, the injection hole can be manufactured by a thin plate orifice member 4 separate from the nozzle and then welded to the nozzle tip by laser welding or the like. It has the effect of being high.

Further, in the fuel injection valve of the present embodiment, the fuel from the opposed fuel passage 24 collides with the flow of the fuel flowing along the outer peripheral wall of the tapered distal end portion 31 of the valve body 3, and the fuel is injected into the injection hole. The fuel is uniformly spread in the longitudinal direction and is introduced into the injection hole 41. Since the fuel uniformly passes through the entire injection hole of the injection hole 41, there is no stagnation portion of the fuel. It works.

The above-described embodiments are exemplifications for explanation, and the present invention is not limited to these embodiments. Those skilled in the art will recognize from the claims, the detailed description of the invention, and the drawings. Modifications and additions are possible without departing from the technical idea of the present invention.

In the above-described embodiment, an example has been described in which the injection holes are slit-shaped elongated holes in order to realize a good flat fan-shaped spray pattern. However, the present invention is not limited thereto. However, if the hole is an elliptical hole or a substantially circular hole having a predetermined diameter, the spread angle is slightly reduced, but a mode of forming a fan-shaped spray can be adopted.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a communication path of a fluid injection valve of the present invention.

FIG. 2 is a schematic view showing a communication passage of a fluid injection valve according to another invention.

FIG. 3 is a perspective view showing a communication path of a fluid injection valve according to another invention.

FIG. 4 is a partial longitudinal sectional view taken along line IV-IV in FIG. 8, showing a tip of the fuel injection valve of the embodiment of the present invention.

FIG. 5 is a bottom view showing a guide of the fuel injection valve of the embodiment.

FIG. 6 is a longitudinal sectional view showing a guide according to the embodiment.

FIG. 7 is a longitudinal sectional view taken along line VII-VII in FIG.

FIG. 8 is a bottom view showing the orifice member of the present embodiment.

FIG. 9 is a partial longitudinal sectional view showing a tip portion of a conventional fuel injection valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel injection valve 2 Guide 3 Valve body 4 Orifice member 10 Injection valve main body 24 Fuel passage 41 Injection hole

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroaki Takeda 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (4)

[Claims] An injection hole formed at a tip of an injection valve, a fluid supply passage provided inside the injection valve body and supplying fluid upstream of the injection hole, and a fluid supply passage between the upstream of the injection hole and the fluid supply passage. In a fluid injection valve including a needle that opens and closes a communication passage, whether a cross-sectional area of the communication passage near one direction substantially orthogonal to an axis of the injection valve is smaller than a cross-sectional area of the communication passage in another region. And a fluid injection valve, wherein no communication passage is provided. 2. The fluid injection valve according to claim 1, wherein
A fluid injection valve, wherein the communication passage is provided only in the vicinity of one direction orthogonal to the axis of the injection valve. 3. The fluid injection valve according to claim 1, wherein
A fluid injection valve, wherein a communication passage is not provided only in the vicinity of one direction orthogonal to the axis of the injection valve. 4. The fluid injection valve according to claim 1, wherein the injection hole has a flat cross-sectional slit shape, and the cross-sectional area of the communication passage is small, or the axis of the injection valve is not provided with the communication passage. A fluid injection valve characterized in that a longitudinal direction of a slit shape is positioned substantially parallel to a direction orthogonal to the first direction.