JPH07310628A - Fuel injection valve - Google Patents

Abstract

PURPOSE:To atomize injection fuel through utilization of resonance phenomenon by a method wherein fuels injected through a pair of injection nozzles are brought into collision with each other. CONSTITUTION:A large injection nozzle 2 having a high sectional area and a small injection nozzle 3 having a low sectional area are formed in the conical part 1b of a nozzle body 1 from the direction of diameter in such a state to be separated in the direction of the axis Ax of the nozzle body 1. Further, the injection axes X1 and X2 of the injection nozzles 2 and 3, respectively, cross each other at the point P of the outside of the nozzle body 1 and a ratio between the square roots of the sectional areas of the two injection nozzles 2 and 3 is set to a value in a range of 1.25-3.5. When a valve body 4 is opened, fuel in a fuel passage 1c is fed to the injection nozzles 2 and 3 and fuels having approximately the same grain size as each other are injected through the injection nozzles 2 and 3. The injection fuels are collided with each other at an intersection P and atomized through resonance phenomenon.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a fuel injection valve for injecting fuel into a cylinder of an internal combustion engine, for example.

[0002]

2. Description of the Related Art Generally, a fuel injection valve for injecting and supplying fuel to each cylinder of an internal combustion engine typified by an automobile engine,
A casing, a nozzle body having a nozzle hole attached to the tip side of the casing, a valve body such as a needle valve that is provided in the nozzle body so as to be displaceable in the axial direction, and opens and closes the nozzle hole, and the valve body. A valve spring for urging the valve toward the valve closing direction,
An electromagnetic actuator that opens the valve body against the spring force of the valve spring is provided, and fuel is injected and supplied according to an injection signal from the control unit.

As a fuel injection valve, there is known a sackhole type fuel injection valve having a sackhole type nozzle body for guiding fuel to an injection hole through a sackhole formed on the tip side. However, in this sackhole fuel injection valve, the fuel accumulated in the sackhole may flow into the combustion chamber due to thermal expansion after the valve is closed, and the amount of HC discharged may increase. For this reason, the suck-less fuel injection valve equipped with a suck-less nozzle body, in which the suck hole that serves as a fuel reservoir is eliminated or made as small as possible, and the inlet of the injection hole is directly opened and closed by the valve body, is also available. More suggested.

Therefore, based on FIG. 11 and FIG. 12, a fuel injection valve according to the prior art, for example, the actual opening sho 60-88.
This will be described with reference to Japanese Patent Publication No. 074, etc.

FIG. 11 is an enlarged cross-sectional view showing an essential part of a suckless fuel injection valve. At the front end side of a casing containing an electromagnetic actuator and the like, a fuel tank, a fuel pump and a pressure regulator (both are shown). The nozzle body 100, to which fuel is supplied via (not shown) or the like, is fixed. A needle valve 101 is provided in the nozzle body 100 so as to be slidable in the axial direction, and the needle valve 101 forms a pair of injection holes 102, 103 formed in the conical tip portion 100a of the nozzle body 100 with the same diameter. Are opened and closed at the same time.

Here, each of these injection holes 102 and 103 has two
The individual pieces make up one set, and as shown in the sectional view of FIG. 12, a total of four sets are provided at intervals of about 90 degrees. In addition, the injection axes of the injection holes 102 and 103 are different from each other in the nozzle body 100.
In order to intersect with the outer peripheral end side in the radial direction, the tip portion 1a of the nozzle body 100 is formed obliquely from the radial direction.

The suckless fuel injection valve according to the prior art is constructed in this way, and when the needle valve 101 is opened by an injection signal, approximately equal amounts of fuel are slanted downward from the injection holes 102 and 103, respectively. Is jetted. Then, the injected fuel collides with each other outside the nozzle body 100 to be atomized, and then flows into the combustion chamber along with the intake air flow.

[0008]

However, in the above-described fuel injection valve according to the prior art, although atomization can be achieved by colliding fuels with each other, the diameters of the injection holes 102 and 103 are simply set to be equal. However, the resonance phenomenon at the time of collision could not be effectively utilized, and the atomization performance was not sufficiently exhibited.

The present invention has been made in view of the above problems of the prior art, and its main purpose is to enhance the atomization performance of fuel by utilizing the resonance phenomenon. Another object of the present invention is to further improve the fuel atomization performance by making the injection pressure uniform and making the particle sizes of the injected fuel substantially equal.

[0010]

Therefore, a fuel injection valve according to the present invention is provided with a nozzle main body having an injection hole radially provided on a tip side, and movably in the axial direction in the nozzle main body. In a fuel injection valve including a valve body that opens and closes the injection hole, a pair of injection holes having different injection hole diameters are axially separated from each other on the tip side of the nozzle body, and the injection is performed from each of the injection holes. The injection axes of the respective injection holes are crossed outside the nozzle body so that the fuels collide with each other.

According to another aspect of the fuel injection valve of the present invention, the nozzle body is provided with a nozzle hole on the tip end side in the radial direction, and the nozzle body is axially movable so as to open and close the nozzle hole. In a fuel injection valve having a valve body, a pair of injection holes having different injection hole diameters are axially separated from each other on the tip side of the nozzle body, and the square root ratio of the cross-sectional area of each injection hole is 1.
It is set so as to fall within the range of 25 to 3.5, and the injection axis of each injection hole is crossed outside the nozzle body so that the fuel injected from each injection hole collides with each other. There is.

Further, in the fuel injection valve of the third aspect, the nozzle body is provided with the nozzle hole on the tip side in the radial direction, and the nozzle body is provided movably in the axial direction to open and close the nozzle hole. In a fuel injection valve including a valve body, a pair of large and small injection holes are provided at the tip end side of the nozzle body so as to be axially spaced so that the larger injection hole is located on the upstream side, and It is characterized in that the injection axes of the respective injection holes intersect outside the nozzle body so that the fuel injected from the holes collides with each other.

On the other hand, in the fuel injection valve of the fourth aspect, the nozzle body is provided with the nozzle hole on the tip side in the radial direction, and the nozzle body is provided movably in the axial direction to open and close the nozzle hole. In a fuel injection valve including a valve body, a pair of large and small injection holes are provided at the tip end side of the nozzle body so as to be axially spaced so that the larger injection hole is located on the upstream side. The square root ratio of the cross-sectional area of the holes is set in the range of 1.25 to 3.5, and the injection axis of each injection hole is set so that the fuel injected from each injection nozzle collides with each other. It is characterized by crossing outside.

[0014]

When the valve body is opened, fuel is injected from a pair of injection holes having different injection hole diameters, and these fuels collide with each other outside the nozzle body to be atomized.

In particular, the square root ratio of the cross-sectional area of each injection hole is 1.2.
When the range is set to 5 to 3.5, the resonance phenomenon at the time of fuel collision can be utilized while ensuring the fuel collision area, so that effective atomization can be performed.

If a pair of large and small injection holes are provided axially spaced so that the one with the larger injection hole diameter is located on the upstream side, the pressure difference applied to the inlet of each injection hole can be made smaller. It is possible to obtain a strong resonance phenomenon by making the particle diameters of the fuel injected from the injection holes approximately the same.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described in detail below with reference to FIGS. 1 to 10 by taking as an example the case where the invention is applied to a suckless fuel injection valve.

First, FIGS. 1 to 4 relate to a first embodiment of the present invention, and FIG. 1 is an enlarged sectional view showing a main part of a fuel injection valve, in which a nozzle body 1 is an electromagnetic actuator. It is fixed to the front end side of the built-in casing by fixing means such as caulking, and is attached so as to face the inside of the combustion chamber (neither is shown).

The nozzle body 1 has a tubular portion 1a fixed to the tip side of the casing, and a conical portion 1b integrally formed on the tip side of the tubular portion 1a. Fuel tanks (not shown) via supply pipes, etc.
A fuel flow path 1c that is continuous with

Further, in the conical portion 1b of the nozzle body 1,
A pair of large and small injection holes 2, which communicate with the fuel flow path 1c.
3 are formed in the radial direction so as to be separated from each other in the axis Ax direction.
More specifically, as shown in FIG. 2, the injection hole 2 having a larger cross-sectional area (hereinafter referred to as “large injection hole 2”) is located on the upstream side and obliquely below the nozzle body 1 from the radial direction. Has been drilled towards. On the other hand, the injection hole 3 having a smaller cross-sectional area (hereinafter referred to as "small injection hole 3") is located downstream of the large injection hole 2 and is bored in the nozzle body 1 from the radial direction to the obliquely lower side. ing.

Here, the injection axis X ₁ of the large injection hole 2 is inclined by a predetermined angle θ _{1 in the} fuel inflow direction with respect to the axis Ax. On the other hand, the injection axis X ₂ of the small injection hole 3 is also inclined with respect to the axis Ax in the fuel inflow direction by a predetermined angle θ ₂ .
Then, these two axes X ₁ and X ₂ are located at the point P outside the nozzle body 1.
By intersecting with each other, the fuel injected from the respective injection holes 2 and 3 collides with each other. It should be noted that the injection holes 2 and 3 are provided so that the ejected liquids collide with each other even when the ejection axis lines X ₁ and X ₂ do not intersect at a point P on the same plane and there is an axial distance between them. Is also possible.

The ratio α (α = (S ₁ ) ^1/2 of the square root of the cross-sectional area S ₁ of the large injection hole 2 to the square root of the cross-sectional area S ₂ of the small injection hole 3
/ (S ₂ ) ^1/2 ) is 1.25 to 3.
It is set in advance to be a value within the range of 5. The square roots of these cross-sectional areas S ₁ and S ₂ are positive values because the negative sign is unsuitable.

A valve body 4 for opening and closing the injection holes 2 and 3 is provided in the nozzle body 1 so as to be movable in the direction of the axis Ax. The valve body 4 includes a long rod-shaped valve shaft 4a inserted into the nozzle body 1, a conical valve portion 4b integrally formed at the tip end side of the valve shaft 4a, and the valve portion 4b. And a seat portion 4c which is integrally formed with the nozzle body 1 and contacts the conical portion 1b of the nozzle body 1 to perform sealing. And
In each of the injection holes 2 and 3, the seat portion 4c of the valve body 4 is the nozzle body 1
It is provided on the downstream side of the position where it makes contact with the inner surface of the conical portion 1c for sealing and thereby constitutes a suckless fuel injection valve as a whole.

Next, in making the present invention, the relationship between the ratio of the square roots of the cross-sectional areas S ₁ and S ₂ of the respective injection holes 2 and 3 (hereinafter referred to as “aperture ratio α”) and resonance, which is uniquely found, The above will be described with reference to FIG.

That is, FIG. 3 is a characteristic diagram showing the correlation between the aperture ratio α and resonance which is a non-linear pull-in phenomenon.
It was found that changing the aperture ratio α in the range of 1 to 5 causes a non-linear change in the resonance strength generated at the time of collision.

Specifically, the strength of resonance due to collision decreases when the aperture ratio α becomes larger than "1", but when it reaches about "1.25", it is equivalent to that when α is "1". of until the value M ₁ to recover, and aperture ratio α is about "1.5" takes a maximum value M _2. Then, as the aperture ratio α is further increased, the resonance strength gradually decreases, and when it reaches “3.5”, the resonance strength becomes M ₁ again.

Therefore, the aperture ratio α is "1.25 to 3.5".
When the range is set to, at least resonance equal to or higher than that of the conventional technique can be obtained. On the other hand, the aperture ratio α is "4.4"
Even in the above cases, it has been found that the strength of resonance exceeds M ₁ .

However, if the aperture ratio α is made too large, the ratio of the fuel collision area decreases, and as a result the amount of atomized fuel decreases. That is, FIG. 4 is a characteristic diagram showing the relationship between the caliber ratio α independently found and the collision area of each fuel, and when the caliber ratio α is increased from “1”, the fuel The ratio of the collision area is a quadratic curve,
It decreases exponentially.

Specifically, when the aperture ratio α is “1.25”, the collision area ratio is β ₁ , and when α is increased to “3.5”, the collision area ratio becomes a small value β ₂ . To take. further,
When the aperture ratio α is increased above this, the ratio of the collision area becomes extremely small, so the area ratio of the part that does not collide increases and one spray penetrates the other spray, causing substantial atomization. There is no state.

Therefore, even if the aperture ratio α is set to "3.5" or more, the ratio of the fuel collision area is significantly reduced.
Atomization performance cannot be improved. Therefore, in the present invention, in consideration of both the strength of resonance and the ratio of the collision area, the aperture ratio α
Is limited to the range of “1.25 to 3.5”.

Next, the operation of the fuel injection valve according to this embodiment will be described.

First, when the valve element 4 is moved upward by an injection signal from a control unit (not shown), the seat portion 4c is separated from the conical portion 1b, and the fuel in the fuel passage 1c is injected into the injection holes 2 and 3 respectively. Flows toward. Then, this fuel is injected into the combustion chamber from the injection holes 2 and 3 along the injection axis lines X ₁ and X ₂ , respectively, and collides from the diagonal direction at the intersection P to be atomized.

Here, in the present embodiment, the large injection hole 2 having a large cross-sectional area S ₁ is vertically spaced apart from the small injection hole 3 having a small cross-sectional area S ₂ in the axial direction Ax so as to be located upstream. Because of the arrangement, the fuel can first flow into the large injection hole 2 having a large cross-sectional area S ₁ , and then the fuel can flow into the small injection hole 3 having a small cross-sectional area S ₂ , whereby each injection hole 2, 3 It is possible to make the particle diameters of the injected fuels respectively injected from the respective components substantially the same and obtain a strong resonance effect.

That is, by providing the large injection hole 2 on the upstream side of the small injection hole 3, the pressure (injection pressure) P ₁ acting on the large injection hole 2
Although the pressure P ₂ acting on the small injection hole 3 is slightly lower than that of the small injection hole 3, since the cross-sectional area S _{2 of the} small injection hole 3 itself is small, the flow velocity of the fuel injected from both injection holes 2 and 3 is substantially the same. It will be about the same.
Since the particle size of the injected fuel is a function of the flow rate, if the flow rates of the injection holes 2 and 3 are substantially the same, the particle sizes of the respective injected fuels are also substantially the same. Therefore, fuels having substantially the same particle diameter can be made to collide with each other, so that the above-described resonance phenomenon can be used more effectively and atomization can be achieved.

On the other hand, if on the contrary, if provided small nozzle hole 3 on the upstream side of the large injection hole 2, the pressure P ₁ applied to large large injection hole 2 of the sectional area S ₁ is lowered, The flow velocity of the fuel injected from the large injection hole 2 decreases, and the particle size of the injected fuel increases. On the other hand, since the pressure P ₂ acting on the side of the small injection hole 3 having a small cross-sectional area S ₂ increases, the flow velocity increases and the particle size of the injected fuel decreases. Therefore, in this case, a relatively large difference occurs in the particle size (mass) of the fuel injected from the injection holes 2 and 3, and the spray having a large particle size penetrates the spray having a small particle size. The resonance phenomenon cannot be used effectively.

According to the present embodiment configured as described above,
The following effects are achieved.

First, a pair of injection holes 2 and 3 having different injection hole diameters.
The provided nozzle body 1 and axially spaced injection axis X ₁ of the injection holes 2,3, X ₂ points of the external nozzle body 1 P
Since the fuel is injected from the injection holes 2 and 3 to collide with each other, a resonance phenomenon can be obtained, and atomization of the injected fuel can be achieved by utilizing this resonance phenomenon. As a result, it is possible to prevent the injected fuel from colliding with and adhere to the wall surface of the combustion chamber, and it is possible to greatly reduce the amount of HC discharged. Further, the temperature of the combustion chamber can be effectively lowered by vaporizing the atomized fuel.

Secondly, since the square root ratio α of the cross-sectional areas S ₁ and S ₂ of the injection holes 2 and 3 is set in the range of 1.25 to 3.5,
As described above, the resonance phenomenon can be utilized while ensuring the fuel collision area, and atomization can be effectively performed.

Thirdly, since the large injection hole 2 having a large cross-sectional area S ₁ is located upstream of the small injection hole 3 having a small cross-sectional area S ₂ , the fuel injected from each injection hole 2, 3 is The particle sizes can be made to be approximately the same, a stronger resonance effect can be obtained, and the atomization performance can be greatly improved.

Fourthly, the present embodiment is applied to a suckless fuel injection valve in which the injection holes 2 and 3 are directly opened / closed by the valve body 4 and the fuel is injected without passing through the suck hole.
The volume of the fuel pool is small. Therefore, the above-described reduction of HC by improving the atomization performance of fuel and the reduction of HC due to the suckless fuel injection valve exert a synergistic effect, so that the amount of HC emission can be suppressed more effectively. You can

Next, the second aspect of the present invention will be described with reference to FIGS. 5 and 6.
An example will be described. In each of the following embodiments, the same components as those in the above-described first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The nozzle body 11 according to the present embodiment has a tubular portion 11a, similar to the nozzle body 1 described in the first embodiment.
The first embodiment is configured by including a conical portion 11b and a fuel flow passage 11c, but two pairs of injection holes, which will be described later, are provided so as to face each other in the radial direction. Is different from.

That is, in the conical portion 11b of the nozzle body 11, the first set of injection holes consisting of the large injection holes 12a having a large cross-sectional area and the small injection holes 13a having a small cross-sectional area, and other large cross-sectional areas. A large injection hole 12b and a second injection hole set including a small injection hole 13b having a small cross-sectional area are provided so as to face each other in the diameter direction of the nozzle body 11. Here, one large injection hole 12a and a small injection hole 13a, and the other large injection hole 12b and a small injection hole 13b have a square root ratio of their cross-sectional areas of 1. as described in the first embodiment. It is set so as to be in the range of 25 to 3.5.

In this embodiment, each large injection hole 12a, 1
2b and the cross-sectional area of each small injection hole 13a, 13b,
The cross-sectional area S ₁ of the large injection hole 2 described in the first embodiment,
Since it is set equal to S ₂ , the value of the aperture ratio α in each injection hole set is the same. However, the present invention is not limited to this, and one aperture ratio α and the other aperture ratio α may be formed differently in consideration of, for example, the shape of the combustion chamber.

The injection axis X ₁ of each large injection hole 12a, 12b is inclined at the same predetermined angle θ ₁ with respect to the axis Ax, while the injection axis X _{2 of} each small injection hole 13a, 13b is also the axis Ax. Since both are inclined at the same predetermined angle θ ₂ , the intersections Pa and Pb where the fuel collides are located on the same plane.

In this embodiment having such a structure, when fuel is injected from each of the injection holes 12a, 12b, 13a, 13b, these injected fuels mutually cross at the intersection points Pa, Pb outside the nozzle body 11. They collide and are atomized by the resonance phenomenon. Therefore, also in this embodiment, the same effect as that of the first embodiment can be obtained.

Although it has been described that the nozzle hole groups face each other in the diametrical direction, the invention is not limited to this. For example, as in the first modification shown in FIG. Two
The injection hole sets 12b and 13b may be arranged so as to be offset by 90 degrees in the circumferential direction. The separation angle θh between the injection hole groups can take various values depending on the shape of the combustion chamber and the like.

Further, as in the second modification shown in FIG.
You may provide three or more sets of one injection hole. That is, FIG.
Is the first set of nozzle holes 12a, 13a and the second set of nozzle holes 12
It shows a case where a total of four injection hole sets b, 13b, the third injection hole sets 12c, 13c, and the fourth injection hole sets 12d, 13d are arranged 90 degrees apart from each other in the circumferential direction. The aperture ratio α in each of the injection hole sets is in the range of 1.25 to 3.5, as in the above-described embodiments, and the aperture ratio α of all the injection hole sets is the same. However, the aperture ratio α may be individually set for each injection hole set.

Next, a third embodiment of the present invention will be described with reference to FIGS. The feature of this embodiment is that a nozzle hole set consisting of a large nozzle hole and a small nozzle hole is attached to the axis A of the nozzle body 21.
It is located at two points in the x direction.

The nozzle body 21 according to this embodiment also includes the tubular portion 2.
1a, the conical portion 21b, and the fuel flow passage 21c, and is different from the nozzle body 1 described in the first embodiment in the arrangement of the injection holes described later.

That is, in this embodiment, the downstream injection hole group and the upstream injection hole group are provided in the conical portion 21b of the nozzle body 21 so as to be separated from each other in the axis Ax direction. Each of these injection hole groups is composed of four injection hole groups arranged 90 degrees apart in the circumferential direction of the nozzle body 21.

Specifically, as shown in FIG. 10, the downstream injection hole group includes a first injection hole group consisting of a large injection hole 22a and a small injection hole 23a, and a large injection hole 22b and a small injection hole 23b. And a third injection hole set including a large injection hole 22c and a small injection hole 23c, and a fourth injection hole set including a large injection hole 22d and a small injection hole 23d. There is.

Similarly, the upstream injection hole group includes the large injection holes 3
A first injection hole group consisting of 2a and a small injection hole 33b, and a large injection hole 3
2b and small injection hole 33b 2nd injection hole group, large injection hole 3
2 c and a small injection hole 33 c, a third injection hole set, and a large injection hole 3
2d and a fourth injection hole group consisting of small injection holes 33d, and each injection hole group of each upstream injection hole group corresponds to the upstream side of each injection hole group of the downstream injection hole group. Is provided.
It should be noted that the positions of the respective injection hole sets of the upstream injection hole group may be rotated from the state shown in FIG. 10 to give a circumferential deviation from the positions of the injection hole sets of the downstream injection hole group. Further, the separation angle θh between the injection hole sets is not limited to 90 degrees, and various values can be adopted.

The aperture ratio α in each nozzle hole set is
It is set in the range of 1.25 to 3.5. Further, in the present embodiment, the injection axis lines X ₁ and X ₂ of each injection hole group of the downstream injection hole group are formed.
A plane where the lower intersection P _L formed by intersecting
A plane upstream injection port group of the injection holes of sets of injection axes X _3, X ₄ is positioned in the upper intersection P _H be formed by crossing the axis Ax
The injection axis lines X ₁ , X ₂ , X ₃ , X ₄ are spaced apart from each other in the direction.
The angle with respect to the axis line Ax is set. As a result, concentric spray can be performed in the combustion chamber. It should be noted that the injection axis lines X ₁ , X ₂ , and X ₂ are arranged so that the intersections P _L and P _H are located on the same plane.
X _3, the angle relative to the axis Ax of X ₄ may be set.

Thus, in this embodiment having such a configuration, the same effect as that of the first embodiment described above can be obtained. In addition to this, in this embodiment, two injection hole groups, each consisting of a plurality of injection hole groups, are vertically arranged with a space in the axial line Ax direction, so that an optimum spray pattern according to the shape of the combustion chamber and the like can be easily achieved. Can be formed.

In the present embodiment, the case where each injection hole group is composed of four injection hole groups has been illustrated, but the present invention is not limited to this, and each injection hole group includes one to three injection hole groups. Or may be composed of 5 or more sets of injection holes. Further, the downstream injection hole groups may be configured with four injection hole groups, the upstream injection hole groups may be configured with three injection hole groups, and so on.

Further, in each of the above-mentioned embodiments, the case of using it for the suckless fuel injection valve has been described as an example, but the present invention is not limited to this, and can be easily applied to a suck hole type fuel injection valve. You can

[0058]

As described in detail above, according to the fuel injection valve of the present invention, a pair of injection holes having different injection hole diameters are provided axially separated from each other, and the injection axis of each injection hole is outside the nozzle body. Since it is configured to intersect with each other, the fuel can be atomized by utilizing the resonance phenomenon at the time of fuel collision. As a result, the amount of HC discharged can be suppressed, and the temperature of the combustion chamber can be effectively lowered.

The square root ratio of the cross-sectional area of each injection hole is 1.2.
Since the range is set to 5 to 3.5, a strong resonance effect can be obtained while ensuring the fuel collision area, and fuel atomization can be performed more effectively.

Further, since a pair of large and small injection holes are provided axially separated so that the injection hole with the larger cross-sectional area is located on the upstream side, the particle size of the fuel injected from each injection hole is increased. Can be made substantially equal, and the stronger resonance effect can be utilized to effectively atomize the fuel.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of a fuel injection valve according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1 with the valve body removed.

FIG. 3 is a characteristic diagram showing the relationship between the aperture ratio and the strength of resonance.

FIG. 4 is a characteristic diagram showing a relationship between a diameter ratio and a ratio of a fuel collision area.

FIG. 5 is a sectional view showing a main part of a fuel injection valve according to a second embodiment of the present invention.

6 is a cross-sectional view taken along line VI-VI in FIG. 5 with the valve body removed.

FIG. 7 is a diagram showing a first modification of the second embodiment.
Sectional drawing similar to.

FIG. 8 is a diagram showing a second modification of the second embodiment.
Sectional drawing similar to.

FIG. 9 is a sectional view showing a main part of a fuel injection valve according to a third embodiment of the present invention.

10 is a cross-sectional view taken along the line XX in FIG. 9 with the valve body removed.

FIG. 11 is a sectional view showing a main part of a suckless fuel injection valve according to a conventional technique.

12 is a cross-sectional view taken along the line AA in FIG.

[Explanation of symbols]

 1, 11 and 21 ... Nozzle body 2, 12a-d, 22a-d, 32a-d ... Large injection hole 3, 13a-d, 23a-d, 33a-d ... Small injection hole 4 ... Valve body

Claims (4)

[Claims] 1. A fuel injection valve provided with a nozzle body having a nozzle hole radially provided on a tip side thereof, and a valve body movably provided in the nozzle body in an axial direction to open and close the nozzle hole. A pair of injection holes having different injection hole diameters are axially separated from each other on the tip side of the nozzle body, and the injection axes of the injection holes are arranged so that the fuel injected from the injection holes collides with each other. A fuel injection valve in which the nozzles are crossed outside the nozzle body. 2. A fuel injection valve including a nozzle body having a nozzle hole radially provided on a tip side thereof, and a valve body movably provided in the nozzle body in an axial direction to open and close the nozzle hole. In the above, the tip side of the nozzle body is provided with a pair of injection holes having different injection hole diameters axially separated from each other, and the square root ratio of the cross-sectional area of each injection hole is in the range of 1.25 to 3.5. And the injection axes of the respective injection holes intersect outside the nozzle body so that the fuel injected from the respective injection holes collides with each other. 3. A fuel injection valve including a nozzle body having a nozzle hole radially provided on a tip side thereof, and a valve body movably provided in the nozzle body in an axial direction to open and close the nozzle hole. In the nozzle body, a pair of large and small injection holes are provided axially separated from each other so that the larger injection hole is located on the upstream side, and the fuel injected from the injection holes collides with each other. As described above, the fuel injection valve is characterized in that the injection axis lines of the respective injection holes intersect outside the nozzle body. 4. A fuel injection valve including a nozzle body having a nozzle hole radially provided on a tip side thereof, and a valve body movably provided in the nozzle body in an axial direction to open and close the nozzle hole. At the tip side of the nozzle body, a pair of large and small injection holes are provided axially spaced so that the larger injection hole is located on the upstream side, and the square root ratio of the cross-sectional area of each injection hole is 1 25-3.5
The fuel injection valve is characterized in that the injection axes of the injection holes intersect outside the nozzle body so that the fuel injected from the injection holes collides with each other.