JP2008121531A - Fluid ejector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide stable spray atomization and stable jetting direction, by using "a fuel flow of large flow strength" heading a nozzle port inlet. <P>SOLUTION: In respective nozzle ports 7 formed in a nozzle port plate 3 of a fuel injection valve, a long wall 7a having the long wall surface length is arranged on the downstream side of "the fuel flow A of large flow strength" heading the nozzle port inlet, and a short wall 7b having the short wall surface length is arranged on the upstream side of "the fuel flow A of large flow strength" heading the nozzle port inlet. The side for strongly pressing fuel flowing in the nozzle ports 7 is arranged as the long wall 7a, and the fuel injection direction can be stabilized by lengthening a distance for restricting fuel. While, atomization of the fuel is improved and stabilized, by opening a repetitive flow of the fuel separating to the opposite side to the outside of the nozzle ports 7 by reflection by being strongly pressed to the long wall 7a without being straightened by a nozzle port wall, by arranging the opposite side of the side for strongly pressing the fuel in the nozzle ports 7 as the short wall 7b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fluid injection device having a structure for ejecting fluid from an injection hole, and more particularly to a technique suitably applied to a fuel injection valve provided with an injection hole plate.

(Conventional technology)
Background Art of the Invention A fuel injection valve will be described as an example.
A fuel injection valve mounted on an internal combustion engine (hereinafter referred to as an engine) is a device for supplying fuel directly or indirectly to a combustion chamber, and fuel injected from the fuel injection valve is collected in an intake pipe or a combustion chamber. Mixed with air to form a combustible mixture.
The mixed state of the injected fuel and air injected from the fuel injection valve affects the engine performance.
As a technique for improving the combustion state of a combustible air-fuel mixture, atomization of injected fuel is known. As a technique for atomizing the injected fuel, a technique for improving atomization of the injected fuel by arranging an injection hole plate provided with a plurality of injection holes at the tip of the fuel injection valve is known (for example, Patent Document 1). reference).

As means for improving atomization of the fuel injected from the nozzle hole, as shown in FIG. 8B, the wall length (the nozzle hole length of the nozzle hole channel) is L, and the nozzle hole diameter (the diameter of the nozzle hole). When D is D, a technique for reducing L / D as the ratio is known.
This will be described with reference to FIGS. 8A and 8B in the case where the nozzle hole diameter D is the same and only the wall length L is changed.

Regardless of the magnitude of L / D, the fuel flows from the nozzle hole inlet into the nozzle hole while containing high turbulent energy. The fuel that has flowed into the nozzle hole will be described separately on the upstream side and the downstream side of “fuel flow A having a high flow strength”.
One side of the nozzle hole wall (upstream side of the “high flow strength fuel flow A”: left side of FIG. 8) by the fuel flowing into the nozzle hole from the upstream side (left side of FIG. 8) of the “high flow strength fuel flow A” Then, separation of inflow fuel occurs.
On the other hand, fuel containing high turbulent energy is pressed against the other side of the nozzle hole wall (the downstream side of the “fuel flow A having a high flow strength”: the right side in FIG. 8). And it reflects in a nozzle hole wall and the separation (repetitive flow) to the opposite side generate | occur | produces. Thereafter, as the fuel flows downstream, the fuel is pressed at a high pressure and released in a spreading direction.

Here, as shown in FIG. 8 (a), when the wall length L is long (L / D is large), the fuel released in the middle of the nozzle hole (fuel imparted with diffusing force) The turbulent energy contained in the nozzle hole is attenuated, and the spread angle of the fuel is suppressed by the downstream nozzle wall. As a result, the area of contact with air is reduced after injection, and the particulate effect is reduced.
On the other hand, as shown in FIG. 8B, when the wall length L is short (when L / D is small), the rectifying effect by the nozzle holes can be suppressed, so that the turbulent energy contained at the time of injection of the nozzle holes is reduced. The fuel is used for fuel splitting (diffusion injection) without being attenuated, and the fuel split fuel is injected from the nozzle hole outlet without being rectified in the nozzle hole. That is, the spread angle of the injected fuel increases. As a result, the area of contact with air increases after injection, and the fine particle effect is enhanced.

(Problems of conventional technology)
However, in the technique of simply reducing L / D as in the prior art, the distance to restrict the fuel flow direction by the nozzle hole wall is shortened, so that the effect of atomization is enhanced, but the target injection direction (injection arrival) In other words, there is a possibility that the injection direction according to the designed injection angle cannot be obtained.
In this way, when the injection direction as designed is not obtained, the variation in the injection direction for each injection and the variation among individuals increase, and this causes a variation in the mixture distribution between cycles or cylinders when the engine is mounted. The engine performance may be impaired.

On the other hand, as another prior art, with respect to a fuel injection valve (swirl type fuel injection valve) provided with fuel swirling means, a notch (step) is provided in the fuel concentration portion at the nozzle hole outlet to shorten a part of the wall length L. In addition, a technique for improving the spread of spray (penetration) is known (see, for example, Patent Document 2).
However, in this other prior art, since a part of the nozzle hole is provided short in the fuel concentration part at the nozzle hole outlet, the distance for restraining the fuel flow direction is shortened, and the variation in the injection direction is increased. Is concerned.
JP-A-11-70347 JP 2004-353661 A

  The present invention has been made in view of the above problems, and its purpose is to make stable atomization of spray by utilizing the flow direction of `` fluid with high flow strength '' toward the fluid inlet of the nozzle hole, An object of the present invention is to provide a fluid ejection device capable of obtaining a stable ejection direction.

[Means of claim 1]
The wall length of the nozzle hole (wall wall length of the nozzle hole flow path from the nozzle hole inlet to the nozzle hole outlet) in the fluid ejecting apparatus employing the means of claim 1 is the “fluid with high flow strength” toward the nozzle hole inlet. The downstream side in the flow direction is provided longer than the upstream side in the flow direction of the “fluid with high flow strength” toward the nozzle hole inlet.
In this way, by providing a longer wall length on the side where the fluid is strongly pressed in the nozzle hole, the distance for restraining the fluid on the side where the fluid is strongly pressed can be increased, and the injection direction of the fluid injected from the nozzle hole can be changed. Can be stabilized.
In addition, by providing a short wall length opposite to the side on which the fluid is strongly pressed against the nozzle hole wall, the repeated flow of fuel that is strongly pressed against the nozzle hole wall and separates to the opposite side due to reflection is provided. Opens out of the nozzle hole without rectification. For this reason, atomization of the spray of the fluid injected from the nozzle hole can be stabilized.
That is, by adopting the means of claim 1, stable atomization of the spray and a stable injection direction can be obtained.

[Means of claim 2]
The means of claim 2 is obtained by applying the means of claim 1 to a fuel injection valve.
Thereby, the injection direction of the fuel injected from the nozzle hole can be stabilized, and atomization of the fuel injected from the nozzle hole can be stabilized.
In this way, since the fuel injection direction and atomization are stabilized, variation in the injection direction for each injection and variation between individuals can be suppressed, and the intended injection direction and atomization can be obtained, and the engine is mounted. There are no problems that sometimes impair engine performance.

[Means of claim 3]
In the fluid injection device (fuel injection valve) employing the means of claim 3, the flow direction of the “fuel flow with high flow strength” toward the nozzle hole inlet is from the outer periphery to the inner periphery when viewed from the drive shaft direction of the valve member. It's what you head for.

[Means of claim 4]
In the fluid injection device (fuel injection valve) employing the means of claim 4, the flow direction of the “fuel flow with high flow strength” toward the nozzle hole inlet is from the inner periphery to the outer periphery as viewed from the drive shaft direction of the valve member. It's what you head for.

[Means of claim 5]
A fluid injection device (fuel injection valve) employing the means of claim 5 is provided.
The wall length of the long wall provided with a long wall length of the nozzle hole channel is L1,
The wall length of the short wall provided with a short wall length of the nozzle hole channel is L2,
If the diameter of the nozzle hole is D,
1.5 ≦ L1 / D
0.5 ≦ L2 / D ≦ 1.3
Is satisfied.
By providing in this way, the injection direction of the fuel injected from the nozzle hole can be stabilized, and atomization of the fuel injected from the nozzle hole can be stabilized.
This stabilizes the fuel injection direction and atomization as described in the above-mentioned “Means of Claim 2”. Therefore, variation in the injection direction for each injection and variation between individuals are suppressed, and as intended. The injection direction and atomization can be obtained, and there is no problem that impairs engine performance when the engine is mounted.

[Means of claim 6]
A fluid injection device (fuel injection valve) employing the means of claim 6 is provided.
The circumferential direction range of the long wall provided with a long wall surface length of the nozzle hole channel is R1,
If the circular arc center in the circumferential direction of the circumferential range R1 of the long wall is R1x,
The arcuate center R1x of the long wall is provided at a predetermined angle with respect to the forward direction of the “fuel flow with high flow strength” toward the nozzle hole inlet.
By providing in this way, the injection direction of the fuel injected from the nozzle hole can be shifted with respect to the forward direction of the “fuel flow with high flow strength”. That is, by controlling the range in which the long wall is provided, the injection direction of the fuel injected from the injection hole can be controlled.

[Means of Claim 7]
A fluid injection device (fuel injection valve) employing the means of claim 7 is provided.
The circumferential direction range of the long wall provided with a long wall surface length of the nozzle hole channel is R1,
If the circumferential direction range of the short wall with a short wall surface length of the nozzle hole channel is R2,
When the injection direction of the nozzle hole is larger than 90 ° with respect to the forward direction of the flow of the “fuel flow with high flow strength” toward the nozzle hole inlet,
R1> R2 is satisfied,
When the injection direction of the injection hole is smaller than 90 ° with respect to the forward direction of the flow of the “fuel flow with high flow strength” toward the injection hole inlet,
R1 <R2 is satisfied.
By providing in this way, the range in which the fluid is strongly pressed in the nozzle hole can be a long wall, and the range on the side where the fuel is pressed against the long wall and separated from the opposite side can be a short wall.

In the best mode 1, the present invention is applied to a fuel injection valve.
The fuel injection valve
(A) a valve body having a substantially cylindrical shape having an annular valve seat on an inner peripheral surface forming a fuel passage;
(B) A valve provided in the valve body so as to be displaceable in the axial direction, and closes the fuel passage in the valve body by sitting on the valve seat and opens the fuel passage in the valve body by separating from the valve seat. A member,
(C) an injection hole plate (an example of an injection hole forming member) provided downstream of the valve seat and formed with injection holes for injecting fuel (an example of fluid) supplied from the fuel passage by separating the valve member; Is provided.

In this fuel injection valve, the fuel injection direction of the injection hole (the central axis of the injection hole) intersects the flow direction of the “fuel flow with high flow strength” toward the injection hole inlet along the upstream surface of the injection hole plate. Is.
The wall length of the nozzle hole channel from the nozzle hole inlet to the nozzle hole outlet is such that the downstream side in the flow direction of the “fuel flow with high flow strength” toward the nozzle hole inlet is “high flow strength” toward the nozzle hole inlet. It is provided longer than the upstream side of the “fuel flow”. That is, the nozzle wall on the downstream side of the “fuel flow with high flow strength” toward the nozzle hole inlet is a long wall provided in the axial direction, and the jet on the upstream side of the “fuel flow with high flow strength” toward the nozzle hole inlet. The hole wall is a short wall provided short in the axial direction.

A first embodiment in which the present invention is applied to a fuel injection valve (injector) will be described with reference to FIGS.
For example, the fuel injection valve may inject fuel directly into the combustion chamber of the engine, or may inject fuel into an intake pipe that supplies combustion air to the combustion chamber of the engine.
The basic structure of this fuel injection valve is well known, and includes a valve body 1, a needle 2, and an injection hole plate 3 as shown in FIG.
In the following description, the fuel injection side of the fuel injection valve is described as the lower side and the opposite side as the upper side for the description of the embodiment, but this is not related to the actual mounting direction on the engine.

The valve body 1 is fixed to a lower portion of an injector housing (hereinafter referred to as a housing) attached to an engine cylinder head or an intake pipe.
The housing has a substantially cylindrical shape, a fuel inlet is provided on the upper side, and fuel pressurized and pressurized from the outside is supplied into the housing through the fuel inlet.
The valve body 1 has a substantially cylindrical shape, and a fuel passage 4 through which fuel supplied into the housing is guided is formed on the inner periphery of the valve body 1.
An annular valve seat 5 on which the needle 2 is seated is formed on the inner peripheral surface of the valve body 1 that forms the fuel passage 4. The valve seat 5 is formed by a valve seat conical surface having a shape obtained by reducing the diameter of the lower portion of the valve body 1 in a tapered shape.

The needle 2 has a substantially rod shape and is provided so as to be displaceable in the axial direction in the housing (including the valve body 1).
The fuel injection valve incorporates drive means for drivingly displacing the needle 2 in the axial direction (vertical direction) within the housing. This driving means may be of a type in which the needle 2 is directly driven in the axial direction by an electric actuator (electromagnetic actuator, piezo actuator, etc.), and the hydraulic pressure for driving the needle 2 in the axial direction is an electric valve (electromagnetic valve, piezo). It may be a hydraulic drive type controlled by an actuator valve or the like.

  A lower portion of the needle 2 has a cylindrical shape, and a contact portion 6 is provided at the lower end of the needle 2 so as to be seated on the valve seat 5 of the valve body 1 and close the fuel passage 4 in the valve body 1. The abutting portion 6 is provided by a boundary portion between a cylindrical surface below the needle 2 and a needle conical surface provided at the lower end of the needle 2. The cone angle of the needle cone surface is larger than the cone angle of the valve seat cone surface described above. The lower end of the needle conical surface, that is, the lower end of the needle 2 is provided flat, and is provided so that the lower end of the needle 2 does not contact the nozzle hole plate 3 while the needle 2 is seated on the valve seat 5. .

The nozzle hole plate 3 is provided downstream of the valve seat 5 and is fixed in close contact with the lower end surface of the valve body 1 by a fixing technique such as welding or a retaining nut.
The nozzle hole plate 3 is formed with a plurality of nozzle holes 7 that communicate the upper surface (the surface communicating with the valve body 1) and the lower surface (the outside).
The position where the nozzle hole 7 is formed will be described.
The injection hole 7 of the first embodiment is provided with an injection hole inlet on the inner side of a portion x where the inner peripheral diameter is the smallest at the lower end of the valve body 1.

For this reason, when the needle 2 is separated from the valve seat 5, the flow direction of the fuel that passes between the valve seat 5 and the contact portion 6 and flows into the nozzle hole plate 3 is as shown in FIG. As viewed from the direction of the drive shaft 2, the outer periphery is directed to the inner periphery. That is, when the needle 2 is separated, the fuel is supplied from the outer periphery toward the inner periphery between the lower end of the needle 2 and the upper surface of the nozzle hole plate 3.
As a result, as shown in FIG. 1, a “fuel flow having a high flow strength” is generated on the upper surface of the nozzle hole plate 3 (corresponding to the upstream surface of the nozzle hole forming member). In the following, “a fuel flow having a high flow strength” is indicated by A, and “a fuel flow having a low flow strength” is indicated by B.

  The injection hole 7 is formed so as to penetrate the injection hole plate 3 in the vertical direction. (Axial direction of the nozzle hole forming hole) is provided to intersect. Specifically, in FIG. 2, as an example of the description, the injection direction of the injection hole 7 (the axial direction of the injection hole forming hole with respect to the upper surface of the injection hole plate 3) is directed toward the injection hole inlet. In the example shown in Example 5 (see FIG. 7) described later, the injection direction of the injection hole 7 is not limited. .

The nozzle hole 7 is a hole that connects the upper surface and the lower surface of the nozzle hole plate 3, and the nozzle hole channel that extends from the nozzle hole inlet (upper opening of the nozzle hole 7) to the nozzle hole outlet (lower opening of the nozzle hole 7). It is formed.
The length of the nozzle hole channel in the nozzle hole axis direction is referred to as the wall length.
The wall length is such that, on the upper surface of the nozzle hole plate 3, the downstream side (the right side of FIG. 1) of the “high flow strength fuel flow A” heading toward the nozzle hole inlet is the “high flow strength fuel stream” heading toward the nozzle hole inlet. A] is longer than the upstream side (the left side in FIG. 1).
That is, the nozzle hole wall on the downstream side (in this embodiment, the side close to the central axis of the fuel injection valve: the inner peripheral side of the nozzle hole plate 3) toward the nozzle hole inlet is axially directed. And a long wall 7a provided long on the upstream side of the "fuel flow A with high flow strength" toward the nozzle hole inlet (in this embodiment, the side different from the central axis of the fuel injection valve: the outer peripheral side of the nozzle hole plate 3). The nozzle hole wall is a short wall 7b that is short in the axial direction.

As shown in FIG. 2, the long wall 7 a and the short wall 7 b are formed by changing the thickness of the nozzle hole plate 3 on the lower surface side. Specifically, the plurality of injection holes 7 in this embodiment are formed in a ring shape around the center of the injection hole plate 3 (the central axis of the fuel injection valve) at a predetermined interval. The above-described long wall 7a and short wall 7b are formed in each nozzle hole 7 by providing a thickness of 3 with the inner peripheral side being thicker with each nozzle hole outlet as a boundary.
In addition, the length change of the long wall 7a and the short wall 7b at the nozzle hole exit may be provided with a step as shown in FIG. 2 (a) or continuously as shown in FIG. 2 (b). It may change to.

As shown in the prior art, when the wall length is L and the nozzle hole diameter is D, atomization of the injected fuel can be improved by reducing L / D, and the injection direction can be stabilized by increasing L / D. Can be improved. The graph of FIG. 3 shows the relationship between L / D and the injection particle size and the relationship between L / D and stabilization of the injection direction in the fuel injection valve.
As shown in FIG.
In the range of 0.5 ≦ L / D ≦ 1.3, atomization of the injected fuel can be expected,
Stabilization of the injected fuel can be expected in the range of 1.5 ≦ L / D.

Therefore, the long wall 7a and the short wall 7b in this embodiment are provided in the following relationship.
The wall surface length of the long wall 7a provided with a long wall surface length of the nozzle hole channel is L1,
The wall length of the short wall 7b provided with a short wall surface length of the nozzle hole channel is L2,
When the diameter of the nozzle hole 7 is D,
1.5 ≦ L1 / D
0.5 ≦ L2 / D ≦ 1.3
Is satisfied.

As described above, each nozzle hole 7 of the fuel injection valve of the first embodiment is provided with the long wall 7a having a long wall surface on the downstream side of the “fuel flow A having a large flow strength” toward the nozzle hole inlet. A short wall 7b having a short wall surface length is provided on the upstream side of the “fuel flow A having a high flow strength” toward the front.
In this way, by providing the long wall 7a on the side on which the fuel flowing into the injection hole 7 is strongly pressed, the fuel strongly pressed against the long wall 7a can be restrained for a long distance, and the fluid injected from the injection hole 7 The injection direction can be stabilized. That is, a stable injection direction can be obtained by the long wall 7a to which the fuel is strongly pressed.

  On the other hand, the side opposite to the side where the fuel is strongly pressed in the nozzle hole 7 is provided as a short wall 7b, so that the nozzle wall rectifies the repetitive flow of fuel which is strongly pressed against the long wall 7a and separates to the opposite side by reflection. Without opening to the outside of the nozzle hole 7. That is, the fuel reflected by the long wall 7a is released to the outside without being interrupted by the short wall 7b, and the atomization of fuel injected from the short wall 7b side is improved and stabilized.

Thus, the fuel injection valve of Example 1 can obtain the atomization of the stable spray and the stable injection direction by applying the present invention.
And by stabilizing the fuel injection direction and atomization, it is possible to suppress the variation in the injection direction for each injection and the variation between individuals, and to obtain the injection direction and atomization as intended. There are no problems that impair engine performance.

A second embodiment will be described with reference to FIG. In the following examples, the same reference numerals as those in the above examples indicate the same functional objects.
As shown in FIG. 4B, the fuel injection valve shown in the second embodiment has a flow direction of the “fuel flow A having a high flow strength” toward the nozzle hole inlet from the outer periphery, as in the first embodiment. It goes to the lap.

In the second embodiment, as shown in FIG. 4A, the circumferential center R1x of the long wall 7a is shifted from the forward direction (0 °) of the flow of “fuel flow A having a high flow strength”. .
Explaining this in words,
The circumferential range of the long wall 7a is R1,
When the circumferential center (circumferential arc center) of the circumferential range R1 of the long wall 7a is R1x, the forward direction (0 °) of the flow of “fuel flow A with high flow strength” toward the nozzle hole inlet Thus, the arc center R1x of the long wall 7a is shifted by a predetermined angle.

  As shown in the second embodiment, the circumferential direction center R1x of the long wall 7a is shifted from the forward direction of the flow of the “high flow strength fuel flow A”, whereby the injection direction of the fuel injected from the injection hole 7 is changed. , “The fuel flow A having a high flow strength” can be shifted with respect to the forward direction of the flow. That is, by controlling the range in which the long wall 7a is provided, the injection direction of the fuel injected from the injection hole 7 can be controlled, and the mixing property of air and atomized fuel can be improved.

A third embodiment will be described with reference to FIG.
In the first and second embodiments, the flow direction of the “fuel flow A having a high flow strength” toward the nozzle hole inlet is directed from the outer periphery toward the inner periphery.
On the other hand, in the third embodiment, the flow direction of the “fuel flow A having a high flow strength” toward the nozzle hole inlet is directed from the inner periphery to the outer periphery.

  As shown in FIG. 5, in the fuel injection valve of the third embodiment, the injection hole inlet is provided outside the portion x where the inner peripheral diameter is minimum at the lower end of the valve body 1. A configuration is adopted in which the fuel supplied to the upper surface of the nozzle hole plate 3 is guided to the outer peripheral nozzle hole inlet by the recess 3a formed on the upper surface of the nozzle hole. For this reason, the flow direction of the “fuel flow A having high flow strength” toward the nozzle hole inlet is from the inner periphery to the outer periphery.

Therefore, in the third embodiment, the long wall 7 a of the injection hole 7 is provided on the outer peripheral side of the injection hole plate 3, and the short wall 7 b of the injection hole 7 is provided on the inner peripheral side of the injection hole plate 3.
In addition, the length change of the long wall 7a and the short wall 7b at the nozzle hole exit may be provided with a step as shown in FIG. 5 (a) or continuously as shown in FIG. 5 (b). It may change to.
Thus, even when the flow direction of the “fuel flow A with high flow strength” toward the nozzle hole inlet is from the inner periphery to the outer periphery, the configuration of the third embodiment is adopted to Similar effects can be obtained.

A fourth embodiment will be described with reference to FIG.
As shown in FIG. 6B, in the fuel injection valve shown in the fourth embodiment, the flow direction of the “fuel flow A having a high flow strength” toward the nozzle hole inlet is from the inner periphery as in the third embodiment. It goes to the outer periphery.

In the fourth embodiment, as shown in FIG. 6A, the circumferential center R1x of the long wall 7a is shifted from the forward direction (0 °) of the flow of the “high flow strength fuel flow A”. .
Explaining this in words,
The circumferential range of the long wall 7a is R1,
When the circumferential center (circumferential arc center) of the circumferential range R1 of the long wall 7a is R1x, the forward direction (0 °) of the flow of “fuel flow A with high flow strength” toward the nozzle hole inlet Thus, the center R1x in the circumferential direction of the long wall 7a is shifted by a predetermined angle.

  As shown in the fourth embodiment, the center R1x in the circumferential direction of the long wall 7a is shifted from the forward direction of the flow of “fuel flow A with high flow strength”, thereby providing “fuel flow with high flow strength toward the nozzle hole inlet”. Even if the flow direction of “A” is from the inner periphery to the outer periphery, the same effect as in the second embodiment can be obtained by adopting the configuration of the fourth embodiment.

A fifth embodiment will be described with reference to FIG.
In each of the above-described embodiments, as shown in FIG. 7A, the injection direction of the injection hole 7 (the axial direction of the injection hole forming hole with respect to the upper surface of the injection hole plate 3) moves toward the injection hole inlet. An example is shown in which a larger fuel flow A ”is provided than 90 ° with respect to the forward direction (0 °).
However, as shown in FIG. 7B, the injection direction of the injection hole 7 is such that the injection direction of the injection hole 7 is in the forward direction (0 °) of the “fuel flow A with high flow strength” toward the injection hole inlet. In contrast, as shown in FIG. 7C, the injection direction of the injection hole 7 is the forward direction of the “fuel flow A having a high flow strength” toward the injection hole inlet (0 °). ) May be provided smaller than 90 °.

Then, as shown in FIG. 7A, when the injection direction of the nozzle hole 7 is larger than 90 ° with respect to the forward direction (0 °) of the “fuel flow A with high flow strength”, FIG. ), The circumferential range R1 of the long wall 7a is longer than the circumferential range R2 of the short wall 7b (R1> R2).
Further, as shown in FIG. 7B, when the injection direction of the nozzle hole 7 is approximately 90 ° with respect to the forward direction (0 °) of “the fuel flow A having a high flow strength”, FIG. ), The circumferential range R1 of the long wall 7a and the circumferential range R2 of the short wall 7b are provided approximately the same (R1≈R2).
Further, as shown in FIG. 7C, when the injection direction of the nozzle hole 7 is smaller than 90 ° with respect to the forward direction (0 °) of the “fuel flow A having a high flow strength”, FIG. ), The circumferential range R1 of the long wall 7a is shorter than the circumferential range R2 of the short wall 7b (R1 <R2).

  By providing in this way, the range in which the fluid is strongly pressed in the nozzle hole 7 can be the long wall 7a, and the range on the side where the fuel is pressed against the long wall 7a and away from the opposite side can be the short wall 7b. Regardless of the injection direction of the injection hole 7, the long wall 7a and the short wall 7b can provide stable atomization of the spray and a stable injection direction.

[Modification]
In the above-described embodiment, an example in which the present invention is applied to a fuel injection valve (for example, a fuel injection valve mounted on a gasoline engine) provided with an injection hole plate 3 has been described, but a valve body 1 in which a valve seat 5 is formed. You may apply this invention to the fuel injection valve (for example, fuel injection valve mounted in a diesel engine) in which the nozzle hole 7 is directly formed in (nozzle body).

  In the above embodiment, the example in which the present invention is applied to the fuel injection valve has been shown. However, the present invention can obtain a stable atomization of the spray fluid and a stable injection direction regardless of the fuel. The present invention may be applied to another injection device (for example, an injection nozzle that injects a vapor deposition material onto a workpiece) that is a technique that can be used and is different from a fuel injection valve.

It is sectional drawing which shows the nozzle hole formed in the nozzle hole plate (Example 1). It is principal part sectional drawing which shows the fuel-injection part of a fuel injection valve (Example 1). It is a graph which shows the relationship between L / D and the injection particle size, and the relationship between L / D and stabilization of an injection direction (Example 1). It is explanatory drawing which shows the relationship between the fuel flow seen from the drive direction of the needle, and a nozzle hole, and principal part sectional drawing which shows the fuel-injection part of a fuel injection valve (Example 2). (Example 3) which is principal part sectional drawing which shows the fuel-injection part of a fuel injection valve. (Example 4) which is explanatory drawing which shows the relationship between the fuel flow seen from the drive direction of a needle, and a nozzle hole, and the principal part which shows the fuel-injection part of a fuel-injection valve. It is explanatory drawing which shows the relationship between the injection direction of a nozzle hole, and the range of a long wall and a short wall (Example 5). It is sectional drawing which shows the nozzle hole formed in the nozzle hole plate (conventional example).

Explanation of symbols

1 Valve body 2 Needle (Valve member)
3 injection hole plate (hole formation member)
4 Fuel passage 5 Valve seat 7 Injection hole 7a Long wall 7b Short wall A Fuel flow with high flow strength (flow of fluid with high flow strength toward the injection hole inlet)
B Fuel flow with low flow strength (flow of fluid with low flow strength toward the nozzle hole inlet)
D Diameter of the nozzle hole L1 Wall length L2 of the long wall Wall length R1 of the short wall R1 circumferential range of the long wall R1x Center of the long wall in the circumferential direction (arc center)
R2 Short wall circumferential range

Claims (7)

An injection hole forming member formed with an injection hole for injecting fluid;
In the fluid ejecting apparatus formed by intersecting the flow direction of the fluid having a large flow strength toward the fluid inlet of the nozzle hole along the upstream surface of the nozzle hole forming member and the fluid jet direction of the nozzle hole,
The wall length of the nozzle passage from the fluid inlet to the fluid outlet of the nozzle hole is
A fluid ejecting apparatus, wherein a downstream side in a flow direction of a fluid having a high flow strength toward the fluid inlet is provided longer than an upstream side in a flow direction of the fluid having a high flow strength toward the fluid inlet. The fluid ejection device according to claim 1,
This fluid injection device is applied to a fuel injection valve that injects fuel,
This fuel injection valve
(A) a valve body having an annular valve seat on an inner peripheral surface forming a fuel passage;
(B) It is provided in the valve body so as to be displaceable in the axial direction, and the fuel passage is closed in the valve body by being seated on the valve seat, and in the valve body by being separated from the valve seat. A valve member for opening the fuel passage;
(C) An injection nozzle that corresponds to the injection hole forming member and that is provided downstream of the valve seat and in which the injection hole for injecting fuel supplied from the fuel passage by the seating of the valve member is formed. A hole plate,
A fluid ejecting apparatus comprising: The fluid ejection device according to claim 2,
The fluid ejecting apparatus according to claim 1, wherein the flow direction of the fuel flow having a high flow strength toward the fluid inlet of the nozzle hole is directed from the outer periphery to the inner periphery as viewed from the drive shaft direction of the valve member. The fluid ejection device according to claim 2,
A fluid ejecting apparatus, wherein a flow direction of a fuel flow having a high flow strength toward a fluid inlet of the nozzle hole is directed from an inner periphery to an outer periphery as viewed from a drive shaft direction of the valve member. In the fluid ejection device according to any one of claims 2 to 4,
The wall length of the long wall provided with a long wall length of the nozzle hole channel is L1,
The wall length of a short wall provided with a short wall length of the nozzle hole channel is L2,
If the diameter of the nozzle hole is D,
1.5 ≦ L1 / D
0.5 ≦ L2 / D ≦ 1.3
A fluid ejecting apparatus characterized by satisfying In the fluid ejection device according to any one of claims 2 to 5,
The circumferential direction range of the long wall provided with a long wall surface length of the nozzle hole channel is R1,
When the arc center in the circumferential direction of the circumferential range R1 of the long wall is R1x,
The long wall circular arc center R1x is provided at a predetermined angle with respect to a forward direction of a fuel flow having a high flow strength toward the fluid inlet of the nozzle hole. In the fluid ejection device according to any one of claims 2 to 6,
The circumferential direction range of the long wall provided with a long wall surface length of the nozzle hole channel is R1,
If the circumferential direction range of the short wall provided with a short wall surface length of the nozzle hole channel is R2,
When the injection direction of the nozzle hole is larger than 90 ° with respect to the forward direction of the fuel flow having a high flow intensity toward the fluid inlet of the nozzle hole,
R1> R2 is satisfied,
When the injection direction of the nozzle hole is smaller than 90 ° with respect to the forward direction of the flow of fuel flow having a high flow strength toward the fluid inlet of the nozzle hole,
A fluid ejecting apparatus satisfying R1 <R2.

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