fuel injection valve

Abstract

In this fuel injection valve, a single virtual circle (C) is set centered on an axis (Y) of a valve hole (7) on the inner surface of a nozzle plate (10), and a boundary surface (B) is set that passes through the axis (Y) and divides the single virtual circle (C) into one virtual half circle (Ca) and the other virtual half circle (Cb). A first fuel injection hole group (50A), which is formed by a plurality of fuel injection holes (51, 52, 53) that have inlets open in the one virtual half circle (Ca), and a second fuel injection hole group (50B), which is formed by a plurality of fuel injection holes that have inlets open in the other virtual half circle (Cb), are provided to the nozzle plate (10). Hole axes (51a, 52a, 53a) of all of the fuel injection holes are slanted so as to be further away from the axis (Y) while extending from the inlet side to an outlet side, and a taper angle (θ) that makes the outlet radius larger than the inlet radius, is applied to all of the fuel injection holes (51, 52, 53). Consequently, the formation of deposits on the nozzle plate can be prevented and a stable fuel injection performance of the fuel injection holes can be maintained.

Description

[Technical Field]

[0001] The present invention relates to a fuel injection valve that is primarily used in a fuel supply system of an engine. [Background technology]

[0002] Conventionally, such a fuel injection valve has been known to include a valve seat member having a conical valve seat and a valve hole passing through the center of the valve seat, a valve body that cooperates with the valve seat to open and close the valve hole, and a nozzle plate joined to the outer end surface of the valve seat member, with two imaginary concentric circles, one large and one small, centered on the axis of the valve hole, set on the inner surface of the nozzle plate facing the valve seat member, and a plurality of fuel nozzle holes respectively positioned on these two imaginary concentric circles drilled into the nozzle plate, with the fuel nozzle holes grouped into a first fuel nozzle hole group and a second fuel nozzle hole group by a boundary surface passing through the axis of the valve hole, and with different taper angles given to each fuel nozzle hole in each fuel nozzle hole group so that the first fuel nozzle hole group and the second fuel nozzle hole group inject fuel in diagonally opposite directions to each other across the boundary surface, as disclosed in Patent Document 1 below. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2006-283703 Summary of the Invention [Problem to be solved by the invention]

[0004] In the fuel injection valve disclosed in Patent Document 1, multiple fuel nozzle holes are arranged on two imaginary concentric circles, one large and one small, on the nozzle plate, which means that the fuel nozzle holes on the large-diameter imaginary circle and the fuel nozzle holes on the small-diameter imaginary circle are particularly close to each other, causing the injected fuel from these fuel nozzle holes to interfere with each other, making it easy for fuel to remain wet on the outer surface of the nozzle plate, which becomes a deposit and causes inconveniences such as narrowing the opening area of ​​the fuel nozzle holes and changing the fuel flow characteristics.

[0005] The present invention has been made in consideration of such circumstances, and aims to provide a fuel injection valve that can prevent deposits from accumulating on the outer surface of the nozzle plate and stabilize the fuel injection performance of each fuel nozzle in the first and second fuel nozzle groups. [Means for solving the problem]

[0006] In order to achieve the above object, the present invention provides a valve seat member having a conical valve seat and a valve hole penetrating the center of the valve seat, a valve body that cooperates with the valve seat to open and close the valve hole, and a nozzle plate joined to the outer end surface of the valve seat member, wherein a single imaginary circle is set on the inner surface of the nozzle plate facing the valve seat member, the center of which is the axis of the valve hole, and a boundary surface is set that passes through the axis of the valve hole and divides the single imaginary circle into one imaginary semicircle and the other imaginary semicircle, and the nozzle plate is provided with a first fuel nozzle group consisting of a plurality of fuel nozzle holes whose inlets open on one imaginary semicircle and a second fuel nozzle group consisting of a plurality of fuel nozzle holes whose inlets open on the other imaginary semicircle, and the hole axes of all the fuel nozzle holes are inclined so as to move away from the axis (Y) of the valve hole as they move from the inlet side to the outlet side, and all the fuel nozzle holes have outlet diameters that are larger than their inlet diameters. Identical Taper angle In addition, the single imaginary circle is set so that the outer diameter side portions of the ends of all the fuel injection holes at the outlet diameter projected onto the inner surface of the nozzle plate on the valve seat member side protrude outward from the inside of the valve hole. This is the first feature.

[0007] In addition to the first feature, the present invention has a second feature in that the taper angle is set to 10° to 17°.

[0008] Furthermore, in addition to the first or second feature, the present invention has a third feature in that each of the fuel nozzle groups has at least a central fuel nozzle located in the center of the group, a pair of first outer fuel nozzles located on either side of the central fuel nozzle, and a pair of second outer fuel nozzles located on either side of the first outer fuel nozzle, and in a plan view of the nozzle plate, the hole axis of the central fuel nozzle intersects the axis of the valve hole, while the hole axes of the first and second outer fuel nozzles are sequentially spaced apart from the axis of the valve hole and intersect with the boundary surface, and when the deflection angles formed by the hole axis of the central fuel nozzle, the hole axis of the first outer fuel nozzle, and the hole axis of the second outer fuel nozzle relative to the boundary surface in the plan view are α, β, and γ, respectively, α>β>γ. [Effects of the Invention]

[0009] According to a first aspect of the present invention, a single imaginary circle is defined on the inner surface of the nozzle plate, with the axis of the valve hole as its center, and a boundary plane is defined that passes through the axis of the valve hole and divides the single imaginary circle into one imaginary semicircle and the other imaginary semicircle, and a first fuel nozzle hole group consisting of a plurality of fuel nozzle holes whose inlets open on one imaginary semicircle and a second fuel nozzle hole group consisting of a plurality of fuel nozzle holes whose inlets open on the other imaginary semicircle are provided on the nozzle plate.With this simple configuration, fuel spray forms can be emitted from the first and second fuel nozzle hole groups in diagonally opposite directions across the boundary plane.Furthermore, mutual interference of fuel injected from all of the fuel nozzle holes can be avoided, fuel wetting on the outer surface of the nozzle plate can be suppressed, and deposit accumulation can be prevented, thereby preventing a reduction in the opening area of ​​the fuel nozzle holes due to deposits and stabilizing fuel injection characteristics.

[0010] According to a second feature of the present invention, by setting the taper angle of all fuel nozzles in the first and second fuel nozzle groups to 10° to 17°, the gas-liquid balance at the outlet of each fuel nozzle can be optimized, thereby achieving good atomization of the injected fuel, and at the same time, fuel wetting on the outer surface of the nozzle plate can be suppressed, effectively preventing the accumulation of deposits.

[0011] According to a third feature of the present invention, when the deflection angles formed by the hole axis of the central fuel nozzle hole, the hole axis of the first outer fuel nozzle hole, and the hole axis of the second outer fuel nozzle hole with respect to the boundary surface in a plan view of the nozzle plate are α, β, and γ, respectively, by setting α>β>γ, not only is it possible to reliably prevent interference between fuel injected from adjacent fuel nozzle holes in each fuel nozzle hole group, but also to ensure a sufficiently large opening angle between the hole axes of the second outer fuel nozzle holes in both fuel nozzle hole groups, thereby preventing interference between fuel injected from both second outer fuel nozzle holes. This effectively suppresses fuel wetting on the outer surface of the nozzle plate, contributing to the prevention of deposit buildup. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a vertical cross-sectional view showing a fuel injection valve according to the present invention in a state where it is attached to an engine. [Figure 2] FIG. 2 is an enlarged view of a portion 2 in FIG. [Figure 3] FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. [Figure 4] FIG. 4 is an enlarged plan view of the nozzle plate as viewed from its inner surface side. [Figure 5] FIG. 5 is a front view showing the fuel injection state of the first and second fuel nozzle hole groups. [Figure 6] FIG. 6 is a graph showing the relationship between the taper angle of the fuel nozzle hole and the particle size of the injected fuel based on test results. [Figure 7] FIG. 7 is a graph showing the relationship between the taper angle of the fuel nozzle hole and the fuel wetted area on the outer surface of the nozzle plate based on test results. [Explanation of symbols]

[0013] I...Fuel injection valve B...Boundary surface C: Virtual circle Ca...One virtual semicircle Cb: The other imaginary semicircle d: Inlet diameter of fuel nozzle D: Fuel nozzle outlet diameter Y: Axis of the valve hole θ: Taper angle of fuel nozzle 3. Valve seat member 7. Valve hole 8. Valve seat 9a...Plane part 10 Nozzle plate 13. Valve body 50A: First fuel nozzle group 50B...Second fuel nozzle group 51... Fuel nozzle hole (center fuel nozzle hole) 51a: Hole axis of central fuel nozzle (central hole axis) 52... Fuel nozzle hole (first outer fuel nozzle hole) 52a... Hole axis of the first outer fuel injection hole (first outer hole axis) 53... Fuel nozzle hole (second outer fuel nozzle hole) 53a... Hole axis of the second outer fuel nozzle hole (second outer hole axis) DETAILED DESCRIPTION OF THE INVENTION

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electromagnetic fuel injection valve I according to the present invention will be described below with reference to the accompanying drawings. In the electromagnetic fuel injection valve I according to the present invention, the fuel injection side is defined as the front, and the fuel inlet side is defined as the rear.

[0015] 1, an intake pipe 40 of an engine E is provided with a mounting hole 41 that opens into an intake port 42, and an electromagnetic fuel injection valve I that can inject fuel into the intake port 42 is mounted in this mounting hole 41. At this time, a cushion member 43 is interposed between the fuel injection valve I and the intake pipe 40.

[0016] The valve housing 2 of the fuel injection valve I is composed of a cylindrical valve seat member 3, a magnetic cylinder 4 which is fitted onto the outer peripheral surface of the rear end of the valve seat member 3 and welded liquid-tight, a non-magnetic cylinder 6 which is abutted against the rear end of the magnetic cylinder 4 and welded liquid-tight, a hollow cylindrical fixed core 5 whose small-diameter front end 5a is fitted onto the inner peripheral surface of the non-magnetic cylinder 6 and welded liquid-tight, and a fuel inlet tube 26 which is fitted onto the outer peripheral surface of the rear end of the fixed core 5 and welded liquid-tight.

[0017] As shown in Figure 2, the valve seat member 3 has a conical valve seat 8, a valve hole 7 that passes through the center of the valve seat 8, a valve guide hole 9 that connects to the large diameter part of the valve seat 8, and a tapered hole 16 that connects to the rear end of the valve guide hole 9.

[0018] Referring again to Figure 1, a portion is left at the front end of the non-magnetic cylinder 6 that does not engage with the fixed core 5, and a hollow cylindrical movable core 12 is fitted from that portion to the magnetic cylinder 4, facing the front end face of the fixed core 5, and a valve body 13 is connected to this movable core 12.

[0019] The valve element 13 is composed of a spherical valve portion 14 that can slide in the valve guide hole 9 to open and close the valve hole 7 in cooperation with the valve seat 8, and a valve rod 15 that is connected to the spherical valve portion 14 by welding its front end, and the rear end of the valve rod 15 is connected to the inner peripheral surface of the movable core 12 by press-fitting and welding. Therefore, the valve element 13 can move up and down within the valve housing together with the movable core 12. The tip of the spherical valve portion 14 is formed into a flat portion 14a (see Figure 2) so that it does not protrude from the outer end surface of the valve seat member 3.

[0020] The valve rod 15 is made of a pipe material with a slot 15a, and its interior communicates with the hollow portion of the movable core 12, and the inside and outside of the valve rod 15 communicate with each other via the slot 15a.

[0021] A retainer 20 made of slotted pipe material is press-fitted and fixed to the middle of the hollow portion of the fixed core 5, and its front end becomes a first spring seat 21. Meanwhile, the rear end of the valve rod 15 ends partway through the hollow portion of the movable core 12, and its rear end becomes a second spring seat 22. A valve spring 23 is compressed between the first and second spring seats 21, 22, and the set load of this valve spring 23 urges the movable core 12 in a direction away from the fixed core 5, i.e., in the valve closing direction of the valve body 13. The set load of this valve spring 23 is adjusted by the depth to which the retainer 23 is press-fitted into the fixed core 5.

[0022] A ring-shaped stopper member 35 made of a non-magnetic material is embedded in the inner peripheral surface of the movable core 12, protruding slightly from the rear end face. This stopper member 35 abuts against the fixed core 5 when the fixed core 5 is attracted to the movable core 12, maintaining a certain gap between the two cores 5 and 12, and contributes to eliminating residual magnetism between the two cores 5 and 12 when the attractive force is released.

[0023] A coil assembly 28 is fitted onto the outer periphery of the valve housing 2 in correspondence with both cores 5, 12. This coil assembly 28 extends from the rear end of the magnetic cylinder 4 to the fixed core 5 and is made of a synthetic resin bobbin 29 fitted onto the outer periphery of these, and a coil 30 is wound around it, and a terminal support arm 29a is formed integrally with the rear end of the bobbin 29 to support the base end of a power supply terminal 33 protruding to one side thereof, and an end of the coil 30 is connected to the power supply terminal 33. A yoke 31 is disposed on the outer periphery of the coil assembly 28. As described above, the fixed core 5, movable core 12, valve spring 23 and coil assembly 28 constitute an electromagnetic actuator 11 that opens the valve element 13 when current is applied to the coil 30 of the coil assembly 28.

[0024] A synthetic resin coating layer 27 is injection molded to cover the outer surfaces of the magnetic cylinder 4 and the fuel inlet tube 26 and to embed the coil assembly 28. At this time, a coupler 34 that houses and holds a power supply terminal 33 and protrudes from one side of the coil assembly 28 is molded integrally with the coating layer 27.

[0025] A fuel filter 36 is attached to the inlet of the fuel inlet pipe 26. A fuel supply cap 46 is fitted onto the outer periphery of the upper end of the fuel inlet pipe 26 via a seal member 47. This supply fuel cap 46 is one of a plurality of fuel supply caps branched off from a fuel rail 45 connected to the discharge port of a fuel pump (not shown).

[0026] Next, the structure of the valve seat member 3 will be described with reference to FIGS.

[0027] The valve guide hole 9 provided in the valve seat member 3 has a cross-sectional shape of a regular polygon (a regular hexagon in the illustrated example) and is formed so as to extend rearward from the large diameter portion of the conical valve seat 8 along the axis Y of the valve hole 7 (which is also the axis of the valve housing 2). That is, in this illustrated example, the valve guide hole 9 is made up of six flat portions 9a and six interior corners 9b of the same width, which are alternately arranged to surround the axis Y of the valve hole 7, and the six flat portions 9a serve as guide portions that guide the lifting and lowering of the spherical valve portion 14, i.e., the opening and closing operation. In addition, a plurality of fuel passages 37 that are connected to the valve seat 8 are defined between the six interior corners 9b and the spherical valve portion 14.

[0028] In the above, the hollow portions of the fuel inlet tube 26, fixed core 5, valve rod 15 and valve housing 2, as well as the slots 15a of the valve rod 15 and the multiple fuel passages 37 around the spherical valve portion 14, form a series of fuel flow paths 39 from the inlet of the fuel inlet tube 26 to the valve seat 8.

[0029] A nozzle plate 10 made of a steel plate is welded liquid-tightly to the front end surface of the valve seat member 3 where the outlet of the valve hole 7 opens, that is, the outer end surface.

[0030] 4, a single imaginary circle C is set on the inner surface of this nozzle plate 10 in a circular region surrounded by the outlet of the valve hole 7, with the axis Y of the valve hole 7 as its center. In addition, a boundary surface B is set that passes through the axis Y of the valve hole 7 and divides the imaginary circle C into one imaginary semicircle Ca and the other imaginary semicircle Cb, and a first fuel nozzle hole group 50A consisting of a plurality of fuel nozzle holes whose inlets open on one imaginary semicircle Ca and a second fuel nozzle hole group 50B consisting of a plurality of fuel nozzle holes whose inlets open on the other imaginary semicircle Cb are drilled in the nozzle plate 10.

[0031] These first and second fuel nozzle groups 50A, 50B each have at least a central fuel nozzle 51 located in the center of the group, a pair of first outer fuel nozzle holes 52 located on either side of this central fuel nozzle hole 51, and a pair of second outer fuel nozzle holes 53 located on either side of these first outer fuel nozzle holes 52.

[0032] The enlarged view in Figure 2 shows the central fuel nozzle hole 51 of the first fuel nozzle hole group 50A, which represents all of the fuel nozzle holes in the first and second fuel nozzle hole groups 50A, 50B. The hole axes 51a, 52a, 53a of all of the fuel nozzle holes 51, 52, 53 are inclined away from the axis Y of the valve hole 7 as they move from the inlet side to the outlet side, and all of the fuel nozzle holes 51, 52, 53 are given a taper angle θ such that the outlet diameter D is larger than the inlet diameter d.

[0033] Referring again to FIG. 4, the first and second fuel nozzle hole groups 50A, 50B have a symmetrical configuration, so only the first fuel nozzle hole group 50A will be described, and a description of the second fuel nozzle hole group 50B will be omitted.

[0034] In the first fuel injection hole group 50A, the hole axis of the central fuel injection hole 51 will be referred to as the central hole axis 51a, the hole axis of the first outer fuel injection hole 52 as the first outer hole axis 52a, and the hole axis of the second outer fuel injection hole 53 as the second outer hole axis 53a. In a plan view of the central hole axis 51a, the first outer fuel injection hole 52, and the second outer hole axis 53a seen from the inner surface side of the nozzle plate 10, the central hole axis 51a intersects with the axis Y of the valve hole 7, while the first and second outer hole axes 52a, 53a are successively spaced apart from the axis Y of the valve hole 7 and intersect with the boundary plane B, and when the deflection angles that the central hole axis 51a, the first outer hole axis 52a, and the second outer hole axis 53a respectively make with respect to the boundary plane B are defined as α, β, and γ, respectively, α>β>γ. In this way, all the fuel nozzle holes 51, 52, 53 are formed.

[0035] Next, the operation of this embodiment will be described.

[0036] When the coil 30 is in an unenergized state, the movable core 12 and the valve element 13 are pressed forward by the set load of the valve spring 22, causing the spherical valve portion 14 to seat on the valve seat 8. Therefore, fuel pumped from a fuel pump (not shown) through a fuel line to the fuel inlet tube 26 fills the series of fuel flow paths 39 and waits there.

[0037] When the coil 30 is energized, the magnetic flux emitted by the coil 30 passes through the fixed core 5, the coil housing 31, the magnetic cylinder 4, and the movable core 12 in sequence, and the magnetic force causes the movable core 12, together with the valve body 13, to be attracted to the fixed core 5 against the set load of the valve spring 22, causing the spherical valve portion 14 of the valve body 13 to separate from the valve seat 8. As a result, the fuel that flows down the multiple fuel passages 37 around the spherical valve portion 14 in the fuel flow path 39 passes through the valve seat 8 and the valve hole 7, and is then injected toward the intake port 42 from all of the fuel nozzle holes 51, 52, 53 of the first and second fuel nozzle hole groups 50A, 50B of the nozzle plate 10.

[0038] Incidentally, a single imaginary circle C set on the inner surface of the nozzle plate 10 is equally divided by a boundary surface B into one imaginary semicircle Ca and the other imaginary semicircle Cb, and the inlets of the fuel nozzle holes 51, 52, 53 of the first fuel nozzle hole group 50A are opened on one imaginary semicircle Ca, and the inlets of the fuel nozzle holes 51, 52, 53 of the second fuel nozzle hole group 50B are opened on the other imaginary semicircle Cb, and the hole axes 51a, 52a, 53a of all the fuel nozzle holes 51, 52, 53 are inclined away from the axis Y as they move from the inlet side to the outlet side. In this simple configuration, the first and second fuel nozzle hole groups 50A, 50B can inject fuel in two diagonal directions that move away from each other in opposite directions on either side of the boundary surface B, as shown in Figure 5, to form inverted V-shaped fuel spray forms F1, F2.

[0039] Moreover, because the fuel nozzle holes 51, 52, 53 of the first and second fuel nozzle hole groups 50A, 50B are all arranged on a single imaginary circle C, a sufficient distance between the fuel nozzle holes 51, 52, 53 can be ensured, and interference between the fuel injected from adjacent fuel nozzle holes 51, 52, 53 can be avoided. This reduces wetting of the outer surface of the nozzle plate 10 due to interference between the injected fuels, and prevents the accumulation of deposits. This prevents the opening area of ​​the fuel nozzle holes from being reduced due to deposits, stabilizing the fuel injection characteristics.

[0040] Furthermore, in each fuel nozzle group 50A, 50B, all of the fuel nozzles 51, 52, 53 are given a taper angle θ such that the outlet diameter D is larger than the inlet diameter d, thereby enabling atomization of the fuel injected from the fuel nozzles 51, 52, 53 of each fuel nozzle group 50A, 50B.

[0041] In particular, by setting the taper angle θ of all fuel nozzle holes 51, 52, 53 of each fuel nozzle hole group 50A, 50B to 10° to 17°, it is possible to optimize the gas-liquid balance at the outlet of each fuel nozzle hole 51, 52, 53, thereby improving atomization of injected fuel. At the same time, it is possible to suppress fuel wetting on the outer surface of nozzle plate 10, thereby preventing deposits from accumulating on the outer surface of nozzle plate 10 and avoiding a reduction in the outlet opening area of ​​fuel nozzle holes 51, 52, 53 due to deposits, thereby stabilizing the fuel injection characteristics of fuel nozzle holes 51, 52, 53.

[0042] According to the test results, as shown in Figure 6, when the taper angle of each fuel nozzle hole 51, 52, 53 is set to less than 10°, the inside of the fuel nozzle holes 51, 52, 53 is mostly occupied by a liquid phase, which prevents the atomization of the injected fuel and makes it impossible to obtain a good fuel spray form.

[0043] Furthermore, as shown in Figure 7, if the taper angle of each fuel nozzle hole 51, 52, 53 is set to more than 17°, the area wetted by the injected fuel on the outer surface of the nozzle plate 10 will exceed the limit value for deposit formation, making it easier for deposits to accumulate.

[0044] Furthermore, in each of the first and second fuel nozzle hole groups 50A, 50B, in a plan view of the nozzle plate 10, the central hole axis 51a intersects with the axis Y of the valve hole 7, while the first and second outer hole axes 52a, 53a are successively spaced away from the axis Y and intersect with the boundary surface B, and when the deflection angles that the central hole axis 51a, the first outer hole axis 52a and the second outer hole axis 53a make with respect to the boundary surface B are α, β and γ, respectively, by setting α>β>γ, not only can interference between the fuels injected from adjacent fuel nozzle holes 51, 52 and 53 in each fuel nozzle hole group 50A, 50B be effectively prevented, but also the opening angle δ between the hole axes 53a, 53a of the second outer fuel nozzle holes 53, 53 of both fuel nozzle hole groups 50A, 50B can be kept sufficiently large, thereby effectively preventing interference between the fuels injected from both second outer fuel nozzle holes 53, 53. As a result, the occurrence of fuel wetting on the outer surface of the nozzle plate 10 can be effectively suppressed, and the accumulation of deposits can be more reliably prevented.

[0045] The present invention is not limited to the above-described embodiment, and various design modifications are possible within the scope of the gist of the present invention.

Claims

1. The valve comprises a valve seat member (3) having a conical valve seat (8) and a valve hole (7) penetrating the center of the valve seat (8), a valve body (13) that cooperates with the valve seat (8) to open and close the valve hole (7), and a nozzle plate (10) that is joined to the outer end surface of the valve seat member (3), A single imaginary circle (C) is set on the inner surface of the nozzle plate (10) on the valve seat member (3) side, the single imaginary circle (C) being centered on the axis (Y) of the valve hole (7), and a boundary surface (B) is set that passes through the axis (Y) of the valve hole (7) and divides the single imaginary circle (C) into one imaginary semicircle (Ca) and the other imaginary semicircle (Cb), a first fuel nozzle hole group (50A) consisting of a plurality of fuel nozzle holes (51, 52, 53) whose inlets open on the one imaginary semicircle (Ca), and a second fuel nozzle hole group (50B) consisting of a plurality of fuel nozzle holes (51, 52, 53) whose inlets open on the other imaginary semicircle (Cb), are provided on the nozzle plate (10); The hole axes (51 a, 52 a, 53 a) of all the fuel nozzle holes (51, 52, 53) are inclined so as to move away from the axis (Y) of the valve hole (7) as they move from the inlet side to the outlet side, and all the fuel nozzle holes (51, 52, 53) are given the same taper angle (θ) such that the outlet diameter (D) is larger than the inlet diameter (d), the single imaginary circle (C) is set so that outer diameter portions of the ends of all the fuel nozzle holes (51, 52, 53) at the outlet diameter (D) projected onto the inner surface of the nozzle plate (10) on the valve seat member (3) side protrude outward beyond the interior of the valve hole (7).

2. 2. The fuel injection valve according to claim 1, wherein the taper angle (θ) is set to 10° to 17°.

3. Each of the fuel nozzle hole groups (50A, 50B) has at least a central fuel nozzle hole (51) located in the center of the group, a pair of first outer fuel nozzle holes (52) located on both sides of the central fuel nozzle hole (51), and a pair of second outer fuel nozzle holes (53) located on both sides of the first outer fuel nozzle holes (52), In a plan view of the nozzle plate (10), a hole axis (51 a) of the central fuel nozzle (51) intersects with an axis (Y) of the valve hole (7), while hole axes (52 a, 53 a) of the first and second outer fuel nozzle holes (52, 53) are sequentially spaced apart from the axis (Y) of the valve hole (7) and intersect with the boundary surface (B), 3. The fuel injection valve according to claim 1, wherein when the deflection angles formed by the hole axis (51 a) of the central fuel nozzle (51), the hole axis (52 a) of the first outer fuel nozzle (52), and the hole axis (53 a) of the second outer fuel nozzle (53) with respect to the boundary surface (B) in the plan view are defined as α, β, and γ, respectively, α > β > γ.

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