fuel injection valve

Abstract

In this fuel injection valve, a taper angle (θ) at which each outlet diameter (D) is made larger than each inlet diameter (d) is given to respective constituting fuel injection holes (51, 52, 53) of first and second fuel injection hole groups (50A, 50B) disposed on a single imaginary circle (C) set in an inner surface of a nozzle plate 10, and different swing angles (α, β, γ) are given between hole axis lines (51a, 52a, 53a) of the fuel injection holes (51, 52, 53) and a boundary surface (B) between the first and second fuel injection hole groups (50A, 50B) in a plan view of the nozzle plate (10), thereby forming recessed grooves (57a, 57b) opening toward the boundary surface (B) in first and second fuel spray forms (Fa, Fb) emitted from the first and second fuel injection hole groups (50A, 50B). Thus, when injection of fuel is targeted at valve parts of a pair of suction valves, the first and second fuel spray forms emitted from the first and second fuel injection hole groups can avoid contacting valve stems of both suction valves as much as possible.

Description

[Technical Field]

[0001] The present invention relates to a fuel injection valve used primarily in the fuel supply system of an engine, and more particularly to an improvement in a port injection type fuel injection valve, that is, a type that injects fuel into an intake port. [Background technology]

[0002] Conventionally, such a fuel injection valve has been known to comprise 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 where the valve hole opens, wherein two imaginary concentric circles, one large and one small, are set on the inner surface of the nozzle plate, with the axis of the valve hole as the center, and a boundary surface is set that includes the axis of the valve hole and divides the two imaginary concentric circles into one imaginary double semicircle and the other imaginary double semicircle, and a first group of fuel nozzle holes consisting of a plurality of fuel nozzle holes arranged on one imaginary double semicircle and a second group of fuel nozzle holes consisting of a plurality of fuel nozzle holes arranged on the other imaginary double semicircle, and wherein first and second fuel spray forms are emitted from the first and second groups of fuel nozzle holes in diagonally opposite directions 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. 2008-169766 Summary of the Invention [Problem to be solved by the invention]

[0004] In the fuel injection valve disclosed in Patent Document 1, the first and second fuel spray forms emitted from the first and second fuel nozzle groups each have a circular cross-sectional shape and fuel particles are distributed throughout the entire nozzle.

[0005] In a fuel injection valve that injects fuel downstream of an engine's intake port, if the fuel injection target point is set at the valve portion of a pair of intake valves due to the compactness of the engine, using a conventional fuel injection valve and directing the first and second fuel forms emitted from the first and second fuel nozzle groups toward the valve portion of the pair of intake valves, the first and second fuel spray forms will come into contact with the valve stems of the pair of intake valves, causing many fuel particles to adhere. Furthermore, if the opening angle between the first and second fuel spray forms is widened to avoid this, the first and second fuel spray forms will then come into contact with the port wall surface more frequently. This phenomenon not only hinders improvements in engine fuel efficiency but also causes an increase in PN (particulate matter count).

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a fuel injection valve that enables the first and second fuel nozzle groups to efficiently emit the first and second fuel spray forms toward both valve portions while avoiding contact with the valve rods of both intake valves as much as possible when the target point for fuel injection is the valve portions of a pair of intake valves. [Means for solving the problem]

[0007] 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 that is joined to the outer end surface of the valve seat member where the valve hole opens, and a single imaginary circle is set on the inner surface of the nozzle plate that faces the valve seat member and that is centered on the axis of the valve hole, and a boundary surface that includes the axis of the valve hole and divides the single imaginary circle into one imaginary semicircle and the other imaginary semicircle is set, and a first fuel nozzle group consisting of a plurality of fuel nozzle holes that open their inlets on one imaginary semicircle and a second fuel nozzle group consisting of a plurality of fuel nozzle holes that open their inlets on the other imaginary semicircle are provided on the nozzle plate, and Connecting the entrance center and the exit center The hole axis is inclined in a direction away from the axis of the valve hole as it moves from the inlet side to the outlet side, and the first and second fuel spray forms are emitted from the first and second fuel nozzle hole groups in diagonally opposite directions across the boundary surface. , i.e., towards the intake valve stem The fuel injection valve is configured to emit a fuel, and the plurality of fuel nozzle holes are given a taper angle in which the outlet diameter is larger than the inlet diameter, and the nozzle plate is projected onto A different deflection angle is given between the axis of each of the plurality of fuel injection holes and the boundary surface. Each of the fuel injection hole groups has at least a central fuel injection hole located in the center of the group, a pair of first outer fuel injection holes located on both sides of the central fuel injection hole, and a pair of second outer fuel injection holes located on both sides of the first outer fuel injection holes, and in a plan view of the nozzle plate, a central injection hole axis which is the hole axis of the central fuel injection hole intersects with the axis of the valve hole, while a first outer injection hole axis which is the hole axis of the first outer fuel injection hole and a second outer injection hole axis which is the hole axis of the second outer fuel injection hole intersect with the boundary surface at successive intervals from the axis of the valve hole, and when the deflection angles made by these central injection hole axis, first outer injection hole axis and second outer injection hole axis with respect to the boundary surface are α, β, γ, α>β>γ, and the positions where the axes at which each of the deflection angles is formed intersect with the boundary surface are arranged in the order of α, β, γ from the center of the imaginary circle, the first and second fuel spray forms toward the interface; , and surrounding the valve rod The first feature is that an open recessed groove is formed.

[0009] Furthermore, the present invention provides 1 of In addition to the above features, each fuel nozzle hole of the first and second fuel nozzle hole groups is formed so that the generatrix extension of the conical surface forming the valve seat passes through the inlet of the fuel nozzle hole and intersects with its inner peripheral surface. 2 The characteristics of this system are as follows: [Effects of the Invention]

[0010] According to the first feature of the present invention, grooves opening toward the boundary surface can be formed in the first and second fuel spray forms emitted from the first and second fuel nozzle hole groups in diagonally opposite directions across the boundary surface. Therefore, when such first and second fuel spray forms are directed toward the valve portions of a pair of intake valves, the grooves in the first and second fuel spray forms receive the valve rods of both intake valves, thereby minimizing contact of the first and second fuel spray forms with both valve rods, which can contribute to improving the fuel efficiency of the engine and reducing PN.

[0011] Also, The present invention 1 According to the feature, in each fuel injection hole group, in a plan view of the nozzle plate, the central hole axis intersects with the axis of the valve hole, while the first outer hole axis and the second outer hole axis are successively spaced apart from the axis of the valve hole and intersect with the boundary surface, and when the deflection angles that these central hole axis, first outer hole axis and second outer hole axis make with respect to the boundary surface are α, β, γ, α>β>γ and the positions at which the axis along which each of the swing angles is formed intersects with the boundary surface are in the order of α, β, γ from the center of the virtual circle. and As it happensBy setting the above, grooves opening toward the boundary surface can be accurately formed in the first and second fuel spray forms. Therefore, when the first and second fuel spray forms are directed toward the valve portions of a pair of intake valves, the grooves in the first and second fuel spray forms accurately receive the valve rods of both intake valves, effectively preventing the first and second fuel spray forms from contacting the pair of valve rods, further contributing to improved fuel economy and reduced PN. Furthermore, not only is interference between fuel injected from adjacent fuel nozzle holes in each fuel nozzle hole group prevented, but the opening angle between the hole axes of the second outer fuel nozzle holes in both fuel nozzle hole groups is sufficiently secured, preventing interference between fuel injected from both second outer fuel nozzle holes. This suppresses fuel wetting on the outer surface of the nozzle plate and contributes to preventing deposit accumulation.

[0012] The present invention 2 According to the feature of (1), each fuel nozzle hole of the first and second fuel nozzle hole groups is formed so that the generatrix extension of the conical surface forming the valve seat passes through the inlet of the fuel nozzle hole and intersects with its inner peripheral surface, so that when the fuel passes through the valve hole and flows into the inlet of each fuel nozzle hole, it collides with the inner peripheral surface of the nozzle hole with force, promoting atomization, and is then injected from the outlet. As a result, a fuel spray form with good fuel atomization can be emitted from each fuel nozzle hole, which can further contribute to improving the fuel efficiency of the engine and reducing PN. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a cross-sectional view of a main part of an engine equipped with a fuel injection valve according to the present invention, showing a state in which the fuel injection valve emits a fuel spray form. [Figure 2] FIG. 2 is a vertical cross section taken along line 2-2 in FIG. [Figure 3] FIG. 3 is an enlarged vertical cross-sectional view of the fuel injection valve in FIG. [Figure 4] FIG. 4 is an enlarged view of part 4 in FIG. [Figure 5] FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. [Figure 6]FIG. 6 is an enlarged plan view of the nozzle plate as seen from the inner surface side. [Explanation of symbols]

[0014] 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 Fa····First fuel spray form Fb...Second fuel spray form θ: Taper angle of fuel nozzle Y: Axis of valve hole 7 α: Deflection angle of central hole axis β: Deflection angle of the first outer hole axis γ: Deflection angle of the second outer hole axis 2. Valve housing 3. Valve seat member 7. Valve hole 8. Valve seat 10 Nozzle plate 13. Valve body 14. Spherical valve section 50A: First fuel nozzle group 50B...Second fuel nozzle group 51... Fuel nozzle hole (center fuel nozzle hole) 52...Fuel nozzle hole (first outer fuel nozzle hole) 53...Fuel passage (second outer fuel injection hole) 51a...Central hole axis 52a...First outer hole axis 53a...Second outer hole axis 57a···First fuel spray groove 57b: Second fuel spray groove DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electromagnetic fuel injection valve I according to an embodiment of 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 side, and the fuel inlet side is defined as the rear side.

[0016] 1, the cylinder head 40 of the engine E is formed with an intake port 42 and a pair of intake valve holes 54a, 54b formed at the downstream end of the intake port 42 and opening into the combustion chamber. A pair of intake valves 55, 56 that open and close the intake valve holes 54a, 54b are slidably supported in the cylinder head 40. The intake valves 55, 56 each consist of an umbrella-shaped valve portion 55a, 56a and a rod-shaped valve rod 55b, 56b. An electromagnetic fuel injection valve I is mounted in the mounting hole 41 of the cylinder head 40 via a seal / cushion ring 43. The fuel injection valve I is positioned so that a boundary plane B (described below) including its axis Y passes through the midpoint between the pair of intake valves 55, 56. The fuel injection valve I is configured to emit first and second fuel spray forms Fa, Fb toward the pair of valve portions 55a, 56a across the boundary surface B.

[0017] As shown in Figures 3 and 4, 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.

[0018] The valve seat member 3 has a valve seat 8 formed with a conical surface with a central angle φ, a valve hole 7 passing through the center of the valve seat 8, a valve guide hole 9 connected to the large diameter portion of the valve seat 8, and a tapered hole 16 connected to the rear end of the valve guide hole 9.

[0019] 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.

[0020] This valve element 13 is composed of a spherical valve portion 14 that can slide in the valve guide hole 9 so as to open and close the valve hole 7 in cooperation with the valve seat 8, and a valve rod 15 whose front end is welded to the spherical valve portion 14, and the rear end of this valve rod 15 is press-fitted into the inner peripheral surface of the movable core 12 and welded to it. Therefore, the valve element 13 can move up and down within the valve housing together with the movable core 12.

[0021] 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.

[0022] 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.

[0023] 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 constant gap between the two cores 5 and 12.

[0024] 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.

[0025] 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.

[0026] 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).

[0027] 4 and 5, the valve guide hole 9 provided in the valve seat member 3 has a regular polygonal cross section (a regular hexagonal cross section in the illustrated example) and is formed 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 fuel injection valve I). That is, the valve guide hole 9 in the illustrated example is composed 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 (i.e., the axis 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. Furthermore, 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] 6, a single imaginary circle C is set on the inner surface of the nozzle plate 10 facing the outer end surface of the valve seat member 3 in a circular region surrounded by the outlet of the valve hole 7, the single imaginary circle C being centered on the axis Y of the valve hole 7. Furthermore, a boundary surface B is set that divides this single imaginary circle C into one imaginary semicircle Ca and the other imaginary semicircle Cb, and a first fuel injection hole group 50A consisting of a plurality of fuel injection holes 51, 52, 53 whose inlets open on one imaginary semicircle Ca, and a second fuel injection hole group 50B consisting of a plurality of fuel injection holes 51, 52, 53 whose inlets open on the other imaginary semicircle Cb are drilled in the nozzle plate 10.

[0031] The first and second fuel nozzle hole groups 50A, 50B each have 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 either side of the central fuel nozzle hole 51, and a pair of second outer fuel nozzle holes 53 located on either side of the first outer fuel nozzle holes 52.

[0032] The enlarged partial view in Figure 4 shows the central fuel nozzle hole 51 of the first fuel nozzle hole group 50A, representing all of the fuel nozzle holes in the first and second fuel nozzle hole groups 50A, 50B. As is clear from this, 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. 6, 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] First, in the first fuel nozzle hole group 50A, the hole axis of the central fuel nozzle hole 51 will be referred to as the central hole axis 51a, the hole axis of the first outer fuel nozzle hole 52 will be referred to as the first outer hole axis 52a, and the hole axis of the second outer fuel nozzle hole 53 will be referred to as the second outer hole axis 53a.

[0035] In a plan view seen from the inner surface side of the nozzle plate 10, the central hole axis 51a is perpendicular to the axis Y of the valve hole 7, while the first outer hole axis 52a is spaced apart from the axis Y of the valve hole 7 and intersects with the boundary surface B, and the second outer hole axis 53a is further spaced apart from the axis Y of the valve hole 7 and intersects with the boundary surface B. 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, it is set that α>β>γ. All of the fuel injection holes 51, 52 and 53 are drilled in the nozzle plate 10 so as to satisfy these conditions.

[0036] Next, the operation of this embodiment will be described.

[0037] 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.

[0038] 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 that order, 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 lift off from the valve seat 8 and open the valve hole 7.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 from the fuel injection holes 51, 52, 53 of the first and second fuel injection hole groups 50A, 50B of the nozzle plate 10 toward the valve portions 55a, 56a of the pair of intake valves 55, 56.

[0039] The first and second fuel nozzle hole groups 50A and 50B are each composed of a plurality of fuel nozzle holes 51, 52, and 53 that open their inlets on one imaginary semicircle Ca and the other imaginary semicircle Cb set on the inner surface of the nozzle plate 10, and in each of the fuel nozzle hole groups 50A and 50B, all of the fuel nozzle holes 51, 52, and 53 are given a taper angle θ in which the outlet diameter D is larger than the inlet diameter d. By tilting the three hole axes 51a, 52a, 53a away from the axis Y of the valve hole 7 as they move from the inlet side to the outlet side, the first fuel nozzle hole group 50A and the second fuel nozzle hole group 50B can inject fuel in two directions diagonally opposite to each other across the boundary surface B, that is, toward the valve portions 55a, 56a of a pair of intake valves 55, 56, as shown in Figure 1, thereby forming first and second fuel spray forms Fa, Fb.

[0040] In particular, each of the fuel nozzle holes 51, 52, and 53 of the first and second fuel nozzle hole groups 50A and 50B is formed so that an extension line 8a of the generatrix of the conical surface forming the valve seat 8 passes through the inlet of each of the fuel nozzle holes 51, 52, and 53 and intersects with the inner peripheral surface thereof, so that when the fuel passes through the valve hole 7 and flows into the inlet of each of the fuel nozzle holes 51, 52, and 53, it collides with the inner peripheral surface of each of the fuel nozzle holes 51, 52, and 53 with great force, promoting atomization, and is injected from the outlet of each of the fuel nozzle holes 51, 52, and 53. As a result, the first and second fuel nozzle holes 51, 52, and 53 can emit first and second fuel spray forms Fa and Fb with excellent fuel atomization, as shown in FIG. 1, which can contribute to improving the fuel economy of the engine and reducing PN.

[0041] Furthermore, in the first and second fuel injection 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 outer hole axis 52a and the second outer hole axis 53a are successively spaced away from the axis Y of the valve hole 7 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 respectively make with respect to the boundary surface B are defined as α, β and γ, by setting α>β>γ, the first and second fuel spray forms Fa, Fb will have a V-shaped or U-shaped cross-sectional shape having grooves 57a, 57b that open toward the boundary surface B, as shown in Figure 2. Therefore, the first and second fuel spray forms Fa, Fb directed toward the valve portions 55a, 56a of the pair of intake valves 55, 56 receive the valve rods 55b, 56b of both intake valves 55, 56 in their recessed grooves 57a, 57b, thereby avoiding contact of the first and second fuel spray forms Fa, Fb with the valve rods 55b, 56b as much as possible and minimizing fuel adhesion to the valve rods 55b, 56b, further contributing to improving the fuel efficiency of the engine and reducing PN.

[0042] Furthermore, all of the fuel nozzle holes 51, 52, 53 of the first and second fuel nozzle hole groups 50A, 50B are arranged on a single imaginary circle C set on the inner surface of the nozzle plate 10, so that a sufficient distance between the fuel nozzle holes 51, 52, 53 can be ensured to avoid interference between the fuel injected from adjacent fuel nozzle holes 51, 52, 53. Also, by sufficiently ensuring the opening angle δ between the second outer hole axes 53a of the two fuel nozzle hole groups 50A, 50B, interference between the fuel injected from both second outer fuel nozzle holes 53 can be effectively prevented. As a result, fuel wetting on the outer surface of the nozzle plate 10 due to interference between the injected fuels can be suppressed, and deposit accumulation can be prevented.

[0043] 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 seat member (3) has a conical valve seat (8) and a valve hole (7) that penetrates 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) where the valve hole (7) opens. A single imaginary circle (C) is set on the inner surface of the nozzle plate (10) that faces the valve seat member (3) and that is centered on the axis (Y) of the valve hole (7), and a boundary surface (B) that includes 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), and the nozzle plate (10) is composed of a plurality of fuel nozzles (51, 52, 53) that open their inlets on one imaginary semicircle (Ca). a first fuel injection hole group (50A) having an inlet opening on the other imaginary semicircle (Cb) and a second fuel injection hole group (50B) having a plurality of fuel injection holes (51, 52, 53) whose inlets open on the other imaginary semicircle (Cb), and hole axes (51a, 52a, 53a) connecting the inlet centers and outlet centers of the plurality of fuel injection holes (51, 52, 53) are inclined in a direction away from the axis (Y) of the valve hole (7) as they move from the inlet side to the outlet side, so that first and second fuel spray forms (Fa, Fb) are emitted from the first and second fuel injection hole groups (50A, 50B) in diagonally opposite directions across the boundary surface (B), i.e., toward valve rods (55b, 56b) of intake valves (55, 56), The plurality of 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), and different deflection angles (α, β, γ) are provided between the hole axes (51 a, 52 a, 53 a) of the plurality of fuel injection holes (51, 52, 53) projected in a plan view of the nozzle plate (10) and the boundary surface (B); 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 central hole axis (51a) which is the hole axis of the central fuel injection hole (51) intersects with an axis (Y) of the valve hole (7), a first outer hole axis (52a) which is the hole axis of the first outer fuel nozzle hole (52) and a second outer hole axis (53a) which is the hole axis of the second outer fuel nozzle hole (53) are sequentially spaced apart from the axis (Y) of the valve hole (7) and intersect with the boundary surface (B); When the swing angles formed by the central hole axis (51 a), the first outer hole axis (52 a), and the second outer hole axis (53 a) with respect to the boundary surface (B) are α, β, and γ, α>β>γ, and the positions where the axes forming each of the swing angles intersect with the boundary surface (B) are arranged in the order of α, β, and γ from the center of the virtual circle (C), The first and second fuel spray forms (Fa, Fb) are formed with recessed grooves (57a, 57b) that open toward the boundary surface (B) and surround the valve rods (55b, 56b). A fuel injection valve.

2. 2. The fuel injection valve according to claim 1, wherein each of the fuel nozzle holes (51, 52, 53) of the first and second fuel nozzle hole groups (50A, 50B) is formed so that an extension line (8a) of a generatrix of a conical surface forming the valve seat (8) passes through an inlet of the fuel nozzle hole (51, 52, 53) and intersects with an inner peripheral surface thereof.

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