JP4085877B2 - Fuel injection valve for internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fuel injection valve for an internal combustion engine, and more particularly to a fuel injection valve suitable for a direct injection spark ignition internal combustion engine.
[0002]
[Prior art]
An example of a fuel injection valve having a surface in the vicinity of the nozzle hole outlet is described in Patent Document 1. In this, an orifice plate provided so as to close the opening of the valve body is formed with a first injection hole and a second injection hole that extends further from the first injection hole to the tip side. The first nozzle hole outlet has a divergent surface over the entire circumferential direction. And thereby, the atomization of the atomized fuel is promoted, and the thickness of the orifice plate is ensured to increase its strength.
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-263205
[Problems to be solved by the invention]
By the way, in a direct-injection spark ignition internal combustion engine that switches between a stratified operation in which a locally rich mixture is formed in the vicinity of the spark plug and a homogeneous operation in which a homogeneous mixture is formed in the cylinder, the stratified operation and the homogeneous It is desirable to change the spray angle and spray direction so that an optimal mixture can be formed both in operation.
[0005]
For example, if the spray angle is set so that the spray reliably reaches the spark plug during the stratified operation in which fuel injection is performed in the latter half of the compression stroke in which the atmospheric pressure in the combustion chamber is high, the fuel is discharged during the intake stroke in which the atmospheric pressure in the combustion chamber is relatively low. This is because during the homogeneous operation in which injection is performed, there is a problem that the spray angle becomes too large and the spray collides with the wall surface, making it impossible to sufficiently homogenize the air-fuel mixture.
[0006]
Here, it is also conceivable to provide a surface in the vicinity of the nozzle hole outlet portion and thereby change the spray direction.
However, the conventional fuel injection valve is not provided with a surface for the purpose of changing the spray direction in the first place, and has a surface in the entire circumferential direction of the nozzle hole outlet. Cannot be controlled in the intended direction.
[0007]
An object of the present invention is to provide a fuel injection valve capable of controlling the direction of spraying with a relatively simple configuration, particularly a fuel injection valve suitable for a direct injection spark ignition internal combustion engine.
[0008]
[Means for Solving the Problems]
Therefore, the present invention includes a plurality of injection holes are arranged in a substantially circular, in the fuel injection valve of the supplied pressurized fuel to an internal combustion engine that directly injected into the cylinder from the plurality of injection holes, the plurality of injection provided upstream of the hole, a turning force applying member for applying a swirling force to the fuel injection, the plurality of provided for any of the injection holes of the injection hole, injection hole spray developed from start of injection when the spray angle at the outlet exceeds a predetermined value, and a guide surface for attracting the Coanda effect part of the circumferential direction of the entire spray from the plurality of injection holes, the guide surface, said plurality of injection It is arrange | positioned inside the line | wire which connects each center of a hole, and changes the spraying direction to the direction which squeezes seeing the said spraying whole, It is characterized by the above-mentioned.
[0009]
【The invention's effect】
According to the fuel injection valve for an internal combustion engine according to the present invention, when a spray that gradually grows from the start of injection grows to a certain large spray angle, a part of the entire spray from the plurality of nozzle holes in the circumferential direction is the Coanda effect. Ru is attracted to the guide surface by. Here, the guide surface is disposed on the inner side of a line connecting the centers of the nozzle holes of the plurality of nozzle holes, and is provided in any one of the plurality of nozzle holes with respect to the spray direction. Change the direction of the overall view. Thereby, the fuel injection with respect to a specific direction at the time of spray development can be restrict | limited.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, reference examples and embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a fuel injection valve according to a first reference example . Fig.1 (a) is a longitudinal cross-sectional view, FIG.1 (b) is the figure (A view of Fig.1 (a)) seen from the nozzle hole side. As shown in the figure, the fuel injection valve 1 includes a cylindrical valve body 2, a needle valve 3 provided so as to be movable in the axial direction within a hollow portion of the valve body 2, and an actuator 4 for moving the needle valve. And comprising.
[0011]
A nozzle hole 5 coaxial with the hollow portion is opened at the tip of the valve body 2, and an inner wall of the valve body 2 on the upstream side of the nozzle hole 5 has a mortar-shaped seat portion 6 centered on the nozzle hole 5. Form. Further, on the upstream side of the seat portion 6, a swirl tip (a turning force applying member) 7 that gives a turning force to the fuel flow is fixed.
[0012]
The needle valve 3 is always urged downward as seen in the figure by a spring (not shown), for example, and closes the nozzle hole 5 by the tip portion of the needle valve 3 being seated on the seat portion 6. The actuator 4 moves the needle valve 3 upward as seen in the figure against the urging force of the spring, so that the tip portion thereof is separated from the seat portion 6 to open the injection hole 5.
[0013]
Further, a guide member 8 is fixed at the tip of the valve body 2 so as to form an inclined surface (guide surface) 8 a with respect to a part of the outlet of the injection hole 5. The guide surface 8a formed by the guide member 8 has an angle slightly larger than the angle formed by the outer periphery when the fuel spray is sufficiently grown with respect to the central axis of the nozzle hole 5, that is, It is formed to have a slightly larger spread than the spread of the grown spray.
[0014]
Here, before fuel injection, the needle valve 3 is seated on the seat portion 6 (the injection hole 5 is closed), and is supplied from a fuel pump (not shown) or the like via the fuel supply passage 9. The high-pressure fuel is held upstream of the seat portion 6.
[0015]
When the needle valve 3 is raised, the injection hole 5 is opened, and the high-pressure fuel starts to be injected from the injection hole 5 through the seat portion 6. At this time, a swirl force is applied to the fuel (flow) by the swirl tip 7 (swirl groove) as a flow field, so that the spray angle gradually increases with the passage of time from the start of injection at the outlet of the nozzle hole 5. The spray grows in the direction of increasing.
[0016]
When the spray grows and the spray angle increases to some extent, the spray is partially drawn in the circumferential direction by the Coanda effect and flows along the guide surface 9a. As a result, the spray direction partially changes and the spray angle increases only in the portion where the guide surface 9a (guide member 9) exists.
[0017]
2 and 3 show the results of calculation of the state of fuel injection from the fuel injection valve 1 by simulation.
FIG. 2 (a) shows a state in which the spray angle is still small during the development of the spray. The swirling flow of fuel develops with the passage of time from the start of injection, and the spray angle gradually widens with the development of this swirling flow. In addition, Fig.3 (a) has shown the state (spray cross section) which looked at the spray in the AA cross section of Fig.2 (a).
[0018]
FIG. 2B shows a state after the spray development in which the spray angle is increased (becomes a predetermined value or more). When a spray angle increases after a certain time has elapsed from the start of injection (when the spray angle becomes greater than or equal to a predetermined angle), the spray on the right side in the figure, that is, the spray on the guide member 8 side is suddenly caused by the Coanda effect (the guide surface 8a). ) And flows along the guide surface 8a. As a result, the spray angle of a part in the circumferential direction changes (becomes larger).
[0019]
FIG. 3 (b) shows a state (spray cross section) in which the spray is seen on the BB cross section of FIG. 2 (b). Compared with FIG. In a situation where the part flows along the guide surface 8a, it can be seen that not only the cross-sectional shape of the spray changes, but also the spray has a break.
[0020]
In addition, the occurrence of a break in the spray in this way is characterized particularly in a state where the atmospheric pressure (back pressure) in the combustion chamber is high. That is, in a state where the atmospheric pressure is high, the spray tends to squeeze normally. However, in the spray where the cut is generated as described above, the air flows into the spray from the cut, so the spray is squeezed. The phenomenon, that is, the phenomenon that the spray angle becomes small does not appear.
[0021]
For this reason, for example, even when applied to the case where fuel is injected in the latter half of the compression stroke where the atmospheric pressure is relatively high, such as a direct-injection spark ignition internal combustion engine, the spray is squeezed under the influence of the atmospheric pressure. Therefore, the combustible air-fuel mixture can be stably formed near the spark plug.
[0022]
According to the fuel injection valve 1 according to the present reference example , the angle between the central axis of the nozzle hole 5 and the guide surface 8a is larger than the angle between the central axis of the nozzle hole 5 and the outer peripheral side of the grown spray. Therefore, when the spray angle is increased to some extent, a part of the circumferential direction is attracted to the guide surface 8a by the Coanda effect, and can be partially changed to a larger spray angle. Thereby, while being able to change the direction of spraying partially, the cut | interruption arises in spraying and the squeezing of spraying can be prevented.
[0023]
In addition, since the swirl tip 7 as a turning force imparting member is provided, the spray gradually grows with the passage of time from the injection and the spray angle increases. For this reason, as will be described later, by appropriately adjusting the time from the injection, the spray direction of the spray is partially injected using the Coanda effect only when necessary, and the Coanda effect is not used. It is also possible to do.
[0024]
Here, the effect when the fuel injection valve 1 is applied to a direct injection spark ignition internal combustion engine will be described. FIG. 4 is a system configuration diagram of a direct injection spark ignition internal combustion engine.
In this engine, an ignition plug 15 is disposed above a combustion chamber 14 formed by a cylinder head 11, a cylinder block 12, and a piston 13, and the fuel injection valve 1 has a guide hole and its injection hole 5 faces obliquely downward. It is provided on the cylinder wall (combustion chamber lateral direction) on the intake port side so that the member 8 (guide surface 8a) is arranged in the direction toward the spark plug 15.
[0025]
The control unit (C / U) 16 receives detection signals from various sensors such as an air flow meter 17, a throttle opening sensor 18, a crank angle sensor 19, and the like. Whether a homogeneous operation for forming a homogeneous air-fuel mixture is performed or a stratified operation for locally forming a rich air-fuel mixture in the vicinity of the spark plug 15 is determined, and a drive signal is output to the fuel injection valve 1. The fuel injection valve 1 and the control unit 16 constitute a fuel injection device.
[0026]
When the conventional fuel injection valve is used, if the fuel injection is performed in a state where the atmospheric pressure in the latter half of the compression stroke is high as in the stratified operation, the spray angle becomes small (spray is deflated), and the spark plug 15 There is a risk of not going. On the other hand, if the spray angle is set large so that the spray reaches the spark plug 15 even in a state where the atmospheric pressure is high in consideration of this, this time, in the homogeneous operation in which fuel injection is performed during the intake stroke, the spray angle Becomes too large and the spray collides with the wall surface.
[0027]
On the other hand, by using the fuel injection valve 1 and arranging the guide surface 8a toward the spark plug 15 as shown in FIG. 4, a part of the circumferential direction of the spray is caused by the Coanda effect. Is directed to the spark plug 15 side, and air can be prevented from flowing into the inside from the breaks generated in the spray to reduce the spray (the spray angle becomes small), so the spark plug 15 can be made without increasing the spray angle setting. An air-fuel mixture can be formed stably in the vicinity.
[0028]
Next, a fuel injection valve according to a second reference example will be described.
In FIG. 4, the fuel injection valve is arranged on the side of the combustion chamber. However, the fuel injection valve according to the second reference example is a so-called direct-up type in which the fuel injection valve is arranged in the upper part of the combustion chamber. This is particularly effective when applied to a direct injection spark ignition internal combustion engine.
[0029]
FIG. 5A is a longitudinal sectional view of the fuel injection valve 10 according to the second reference example , and FIG. 5B is a view as seen from the injection hole side (view B in FIG. 5A). The fuel injection valve 10 according to this reference example differs from the first embodiment (FIG. 1) in that a plurality of discontinuous guide surfaces 8a (guide members 8) are provided in the circumferential direction of the injection hole 5. To do. Since other configurations are the same as those of the first embodiment, description thereof is omitted.
[0030]
6A shows a state when the spray from the fuel injection valve 10 has grown (a state after the development of the spray), and FIG. 6B shows a cross section taken along the line CC in FIG. 6A. The state which looked at the spray from the fuel injection valve 10 side (spray cross section) is shown.
[0031]
In this reference example , when a plurality of guide surfaces 8a are provided, only the spray corresponding to the plurality of guide surfaces 8a is attracted to the guide surface 8a by the Coanda effect (spray angle increases). Then, when the cross section of this spray is seen, since the spray is cut like the first reference example (see FIG. 6 (b)), the fuel injection valve 10 allows the fuel in a state where the atmospheric pressure is high. Even if the injection is performed, it is possible to prevent the spray from being deflated.
[0032]
As described above, according to the fuel injection valve 10 according to this reference example , by appropriately providing the plurality of guide surfaces 8a on the circumference of the injection hole 5, it is possible to widen an arbitrary portion of the spray and thereby more since many breaks occurs, it is possible to more reliably prevent the spray collapses like.
[0033]
Furthermore, a fuel injection valve according to a third reference example will be described.
FIG. 7A is a longitudinal sectional view of the fuel injection valve 20 according to the third reference example , and FIG. 7B is a view (viewed as C in FIG. 7A) viewed from the injection hole side. This fuel injection valve 20 is of a type in which fuel is injected from a so-called hole nozzle. Compared to the first and second embodiments (FIGS. 1 and 5), the number of injection holes 5 is not one, The difference is that a plurality of fine nozzle holes 51 are arranged in a circle. Since other configurations are the same as those of the first and second reference examples , description thereof is omitted.
[0034]
In the fuel injection valve 20, the guide surface 8a is not provided in each of the injection holes 51, but any one of the plurality of fine injection holes 51 is targeted, and spraying from the target injection hole 51a is performed. On the other hand, the Coanda effect is used. And as shown in FIG.7 (b), the guide surface 8a forms a surface with respect to the target nozzle hole 51a in the position outside the line (circle) passing through the center of each nozzle hole 51. Is provided.
[0035]
That is, in this fuel injection valve 20, the spray angle of a part of the entire spray changes depending on whether or not the spray from the target nozzle hole 51a among the plurality of nozzle holes 51 is attracted to the guide surface 8a by the Coanda effect. It is characterized by doing. Note that the target nozzle hole 51a is not limited to one, and may be a plurality. Further, the guide surface 8a has an angle slightly larger than the spray angle when the spray injected from the target injection hole 51a is sufficiently grown, like the fuel injection valve 1 according to the first embodiment. Is formed.
[0036]
8 and 9 show the state of spray from the fuel injection valve 20.
FIG. 8 shows a state during spray development where the spray angle is still small. In this case, the Coanda effect does not yet appear, and the spray is not attracted to the guide surface 8a (not along the guide surface 8a). Therefore, when the spray is viewed from the fuel injection valve 20 side in the DD section, the spray from the target nozzle hole 51a is the same as that from the other nozzle holes 51 (see FIG. 8B).
[0037]
FIG. 9 shows a state after spray development in which the spray angle is increased. In this case, the spray from the nozzle hole 51a is attracted to the guide surface 8a by the Coanda effect (becomes along the guide surface 8a). Accordingly, when the spray is viewed from the fuel injection valve 20 side in the EE cross section, the spray direction from the nozzle hole 51a is changed, and when viewed as the entire spray, a partial spray angle in the circumferential direction is increased. (See FIG. 9B).
[0038]
According to the fuel injection valve 20 according to this reference example , in the fuel injection valve having a plurality of injection holes, a line connecting the center of each injection hole 51 to any one of the plurality of fine injection holes 51 By disposing the guide surface 8a on the outer side, the spray direction from the target nozzle hole 51a can be changed to the direction in which the spray spreads using the Coanda effect. Therefore, if the target nozzle hole 51a is arranged on the spark plug side, the spray can be directed to the spark plug without changing the setting of the spray angle.
[0039]
Next, a description will be given of a fuel injection valve according to implementation embodiments of the present invention.
10 (a) is a longitudinal sectional view of a fuel injection valve 30 according to the implementation embodiments of the present invention, in FIG. 10 (b) drawing as seen from the nozzle hole side (D plan view in FIG. 10 (a)) is there. This fuel injection valve 30 is also of the type in which fuel is injected from a plurality of hole nozzles, as in the third reference example (FIG. 7), but it is not possible to spread a part of the spray using the Coanda effect. The difference is that the spread of a part of the spray is reduced.
[0040]
In the fuel injection valve 30, a guide surface 8a is formed inside a circle passing through the center of each injection hole 51 with respect to the target injection hole 51a with respect to the fuel injection valve 20 according to the third reference example. Is different. It should be noted that there may be a plurality of target nozzle holes 51a, and the guide surface 8a forms a surface that is slightly larger than the spray angle when the spray sprayed from the target nozzle holes 51a has grown sufficiently. This is the same as in the case of the fuel injection valve 20 of the third reference example .
[0041]
11 and 12 show the state of spray from the fuel injection valve 30. FIG.
FIG. 11 shows a state in which the spray angle is still small during the development of the spray. In this case, the Coanda effect does not yet appear, and the spray is not attracted to the guide surface 8a. Therefore, when the spray is viewed from the fuel injection valve 30 side in the FF cross section, the spray from the target nozzle hole 51a is the same as that from the other nozzle holes 51 (see FIG. 11B).
[0042]
FIG. 12 shows a state after spray development in which the spray angle is increased. In this case, the spray from the target nozzle hole 51a is attracted to the guide surface 8a by the Coanda effect. Therefore, when the spray is viewed from the GG cross section from the fuel injection valve 30 side, the spray direction from the nozzle hole 51a is changed, and when viewed as the entire spray, the spray angle of a part of the circumferential direction becomes small. (See FIG. 12B).
[0043]
According to the fuel injection valve 30 according to this embodiment, in the fuel injection valve having a plurality of injection holes, the line connecting the center of each injection hole 51 to any one of the plurality of fine injection holes 51 by arranging the guide surface 8a on the inner side, it is possible to change the spray direction from the nozzle hole 51a of interest by utilizing the Coanda effect to spray deflated direction. This makes it possible to limit fuel injection in a specific direction.
[0044]
So far, it has been described that the spray angle (spray direction) is partially changed using the Coanda effect by providing the guide surface 8a at the outlet of the nozzle hole (5, 51). When (1, 10, 20, 30) is applied to a direct-injection spark ignition internal combustion engine, use / non-use of this Coanda effect, that is, a part of the circumferential direction of the spray is guided by the Coanda effect 8a. It is also effective to switch between the case of being along the line and the case of not being along the line depending on the operation state.
[0045]
For example, in a direct-injection spark-ignition internal combustion engine in which the fuel injection valve is disposed in the combustion chamber lateral direction, the fuel injection valve 1 according to the first reference example (with the guide surface 8a facing the spark plug 15) ( 1) is provided. During the stratification operation, as shown in FIG. 13A, by causing a part of the spray to follow the guide surface 8a by the Coanda effect, the spray is guided to the spark plug 15 side, and the spark plug 15 A compact mixture is formed in the vicinity.
[0046]
On the other hand, at the time of homogeneous operation, as shown in FIG. 13B, the spray hits the spark plug 15 directly by preventing a part of the spray from being along the guide surface 8a (not using the Coanda effect). In this way, a homogeneous air-fuel mixture is formed throughout the combustion chamber 14.
The same applies to the case where the fuel injection valve 20 according to the third reference example is used.
[0047]
Further, in the direct-type direct injection spark ignition internal combustion engine, the fuel injection valve 10 (FIG. 5) according to the second reference example is provided. In the stratified operation, as shown in FIG. 14A, a part of the spray is not allowed to follow the guide surface 8a (the Coanda effect is not used), so that the spray angle (θ1) is relatively small. The stratified mixture is formed in the vicinity of the spark plug 15 while promoting atomization using the piston bowl 13a on the upper surface of the piston 13 while avoiding the spray directly hitting the spark plug 15.
[0048]
On the other hand, at the time of homogeneous operation, as shown in FIG. 14B, a spray angle (θ2) is increased and atomization is further promoted by causing a part of the spray to follow the guide surface 8a by the Coanda effect. To form a homogeneous mixture in the combustion chamber 14. Incidentally, sprayed by the third but Ru similarly Der case of using the fuel injection valve 20 according to the reference example, in the case of using the fuel injection valve 30 according to the above you facilities embodiment, utilizing the Coanda effect Will reduce the angle. [0049]
The use / non-use of the Coanda effect, that is, switching between the case where a part of the circumferential direction of the spray is along the guide surface 8a and the case where it is not along, can be performed, for example, as follows. is there.
(1) As described above, a so-called spiral injection valve that generates a swirling flow in fuel grows with the passage of time from injection and gradually increases the spray angle. For this reason, use / non-use of the Coanda effect can be switched by appropriately adjusting the time from injection. For example, when the Coanda effect is not used, fuel injection is repeated by repeating injection (ie, repeating a short injection period) before the Coanda effect occurs and the injection is stopped before the Coanda effect occurs. When using the Coanda effect, a long injection period during which the spray grows may be used.
(2) Further, since the swirl injection valve has a characteristic that the spray angle becomes large when the fuel injection pressure is high and the spray angle becomes small when the fuel injection pressure is low, the fuel injection pressure is used when the Coanda effect is used. When the coanda effect is not used, the fuel injection pressure may be lowered.
(3) Since the spray is affected by the back pressure (atmospheric pressure in the combustion chamber), the use / non-use of the Coanda effect can be switched by controlling the back pressure. For example, in general, the lower the back pressure, the larger the spray angle, so when using the Coanda effect, fuel injection is performed near the bottom dead center, and when not using the Coanda effect, the state is close to top dead center In this case, the fuel injection may be performed. The back pressure may be increased by increasing the closing time of the intake valve and decreasing the back pressure by delaying the closing time of the intake valve.
(4) Further, when a two-fluid injection valve capable of injecting fuel and air is used as the fuel injection valve, the spray angle can be adjusted by the mass ratio of the fuel to the injected air, so the Coanda effect is used. In such a case, the fuel mass ratio may be increased, and when the Coanda effect is not used, the fuel mass ratio may be decreased.
[0050]
According to the above (1) to (4), use / non-use of the Coanda effect can be switched relatively easily without complicating the structure of the injection valve itself. In this way, the spray directly hits the spark plug 15 by switching the use / non-use of the Coanda effect and changing the partial spread of the spray (that is, spray angle, spray direction) according to the operating state. Although atomization can be promoted while avoiding this, there is also an effect that deposits near the nozzle hole 5 (or nozzle hole 51) can be treated.
[0051]
That is, conventionally, it was difficult to clean except the inside of the nozzle hole, but the flow field at the nozzle hole outlet changes by switching the use / non-use of the Coanda effect. Deposits can be removed by fuel.
[0052]
Therefore, as described above, the deposit at the nozzle hole outlet can be removed simultaneously by switching the use / non-use of the Coanda effect according to the operating state.
[Brief description of the drawings]
FIG. 1 is a view showing a fuel injection valve according to a first reference example .
FIG. 2 is a diagram showing the results of numerical calculation of the state of spray from a fuel injection valve according to a first reference example .
FIG. 3 is a view showing a result of a numerical calculation of a cross section of spray from a fuel injection valve according to a first reference example .
FIG. 4 is a diagram illustrating a case where the fuel injection valve according to the first reference example is applied to a direct injection spark ignition internal combustion engine.
FIG. 5 is a view showing a fuel injection valve according to a second reference example .
FIG. 6 is a view showing a state of spray from a fuel injection valve according to a second reference example .
FIG. 7 is a view showing a fuel injection valve according to a third reference example .
FIG. 8 is a view showing a state of spray from a fuel injection valve according to a third reference example (during spray development).
FIG. 9 is a diagram showing a state of spray from a fuel injection valve according to a third reference example (after spray development).
10 is a diagram showing a fuel injection valve according to implementation embodiments of the present invention.
11 is a diagram showing the spray from the fuel injection valve according to implementation embodiments state (during spray development).
12 is a diagram showing a state (after spraying development) of the spray from the fuel injection valve according to implementation embodiments.
13 is a diagram showing a fuel injection valve disposed in the combustion chamber laterally straight eruption flowers ignition type internal combustion engine.
[14] The fuel injection valve disposed in the combustion chamber top, illustrates a so-called directly above type linear eruption flowers ignition type internal combustion engine.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,10,20,30 ... Fuel injection valve, 2 ... Valve body, 3 ... Needle valve, 4 ... Actuator, 5,51 ... Injection hole, 6 ... Seat part, 7 ... Swirl tip, 8 ... Guide member, 8a ... Guide surface, 13 ... piston, 14 ... combustion chamber, 15 ... spark plug

Claims (6)

In a fuel injection valve of an internal combustion engine that has a plurality of injection holes arranged in a substantially circular shape and directly injects supplied pressurized fuel into a cylinder ,
A turning force applying member provided on the upstream side of the plurality of nozzle holes, for applying a turning force to the fuel to be injected;
When the provided for a plurality of any of the injection holes of the injection hole, the spray angle in DI hole outlet spray is developed from start of injection becomes equal to or greater than a predetermined value, the entire spray from the plurality of injection holes And a guide surface that draws a part of the circumferential direction by the Coanda effect ,
The fuel injection of the internal combustion engine, wherein the guide surface is disposed inside a line connecting the centers of the nozzle holes of the plurality of nozzle holes, and changes the spray direction to a direction of squeezing as viewed in the entire spray. valve. Depending on the operating conditions of the engine, when the circumferential direction part of the entire spray is along the guide surface by the Coanda effect, and when the circumferential direction part of the entire spray is not along the guide surface, 2. The fuel injection valve for an internal combustion engine according to claim 1, wherein: 3. The fuel injection is performed by repeating a short injection period in a case where a part of the entire spray in the circumferential direction is not along the guide surface and is along the guide surface. The fuel injection valve of the internal combustion engine described. If not along a part of the circumferential direction of the entire spray to said guide surface, with respect to the case be along the guide surface, according to claim 2 or claims, characterized in that by lowering the injection pressure the fuel is injected Item 6. A fuel injection valve for an internal combustion engine according to Item 3 . If not along a part of the circumferential direction of the entire spray to said guide surface, with respect to the case be along the guide surface, claims 2 to, characterized in that the fuel is injected at a high condition the combustion chamber pressure 5. A fuel injection valve for an internal combustion engine according to any one of 4 above. When a portion of the entire spray is not along the guide surface, fuel is injected near the top dead center, and when it is along the guide surface, fuel is injected near the bottom dead center. The fuel injection valve for an internal combustion engine according to claim 5 .

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