Electromagnetic fuel injection valve

Abstract

In an electromagnetic fuel injection valve according to the present invention: an annular fuel collection chamber 49 is provided between a valve seat 8 and a valve hole 7, and a flat fuel diffusion chamber 50 to which an outlet of the valve hole 7 opens is provided between a valve seat member 3 and a nozzle plate 10 joined to a front end surface thereof; a plurality of fuel injection holes 17a, 17b opening to the fuel diffusion chamber 50 are provided in the nozzle plate 10, separated in the radial direction from the valve hole 7; the number of fuel injection holes 17a, 17b is greater than the number of fuel channels 37; and a plurality of fuel injection holes 17a, 17b not in phase with the fuel channels 37 are provided. Through this configuration, fuel injection performance of the plurality of fuel injection holes when the valve is open can be stabilized while eliminating the need for phase alignment between the plurality of fuel channels surrounding a spherical valve part and the plurality of fuel injection holes provided in the nozzle plate.

Description

[Technical Field]

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

[0002] Conventionally, such an electromagnetic fuel injection valve has been known to comprise a valve housing having at its front a valve seat member with a conical valve seat, a valve hole penetrating the center of the valve seat, and a plurality of fuel injection holes arranged around the central axis of the valve hole downstream of the valve hole, a valve body having at its front end a spherical valve portion that cooperates with the valve seat to open and close the valve hole, and an electromagnetic actuator that is disposed in the valve housing behind the valve seat member and that, when energized, causes the valve body to open, and the valve seat member is provided with a valve guide hole that is formed by alternatingly arranging a plurality of flat portions that guide the opening and closing movement of the spherical valve portion and a plurality of interior angular portions that surround the spherical valve portion and define a plurality of fuel passages that are connected to the valve seat in the circumferential direction of the valve seat member, as disclosed in Patent Document 1 below. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent No. 5939669 Summary of the Invention [Problem to be solved by the invention]

[0004] In the electromagnetic fuel injection valve disclosed in Patent Document 1, a cylindrical fuel merging chamber is connected to the outlet of the valve hole, and the bottom wall of this fuel merging chamber is drilled with fuel nozzle holes that surround the axis of the valve hole and are the same number and in phase as the multiple fuel passages, so that when the valve body is opened, the fuel that has flowed down the multiple fuel passages passes through the fuel merging chamber and is injected to the outside from the corresponding fuel nozzle holes.

[0005] In the above-mentioned system, although a fuel confluence chamber is connected to the outlet of the valve hole, the distance between the fuel passage and the fuel nozzle is relatively short, so in order to maintain constant fuel injection performance of each fuel nozzle, it is necessary to accurately position the same number of fuel nozzles in the same phase for multiple fuel passages.

[0006] However, in order to meet the above requirements, high precision in processing and assembly of the components is required, which is disadvantageous for mass production.

[0007] The present invention has been made in consideration of the above circumstances, and aims to provide an electromagnetic fuel injection valve that enables stabilization of the fuel injection performance of each fuel nozzle while eliminating the need to align the phases of the multiple fuel passages surrounding the spherical valve portion with the multiple fuel nozzles. [Means for solving the problem]

[0008] In order to achieve the above object, the present invention comprises a valve housing provided at the front with a conical valve seat, a valve hole penetrating the center of the valve seat, and a valve seat member having a plurality of fuel injection holes arranged around the axis of the valve hole on the downstream side of the valve hole, a valve body having a spherical valve portion at the front end portion which cooperates with the valve seat to open and close the valve hole, and an electromagnetic actuator provided in the valve housing behind the valve seat member and which, when energized, causes the valve body to open. The valve seat member is provided with a valve guide hole which guides the opening and closing operation of the spherical valve portion, and a valve seat member is provided between the valve guide hole and the spherical valve portion, surrounding the spherical valve portion. In an electromagnetic fuel injection valve in which a plurality of fuel passages connected to the valve seat are defined, a first feature is that an annular fuel collection chamber is provided between the valve seat and the valve hole, and a flat fuel diffusion chamber with a larger diameter than the valve hole, into which the outlet of the valve hole opens, is provided between the valve seat member and a nozzle plate joined to the front end surface of the valve seat member, and a plurality of fuel nozzle holes opening into the fuel diffusion chamber are provided in the nozzle plate radially spaced from the valve hole, the number of the plurality of fuel nozzle holes is greater than the number of the fuel passages, and the nozzle plate includes a plurality of fuel nozzle holes that are not in phase with the fuel passages.

[0009] In addition to the first feature, the present invention has a second feature in that the valve guide hole is forged to have a cross-sectional polygonal shape with 4 to 6 interior corners, and the fuel passage is defined between the interior corners and the spherical valve portion.

[0010] Furthermore, in addition to the first or second feature, the present invention has a third feature in that the plurality of fuel nozzle holes are arranged on an imaginary circle centered on the valve hole axis, and these fuel nozzle holes are grouped into a first fuel nozzle hole group consisting of a plurality of fuel nozzle holes arranged on one semicircle of the imaginary circle divided by a bisector, and a second fuel nozzle hole group consisting of a plurality of fuel nozzle holes arranged on the other semicircle of the imaginary circle, the hole axis of each fuel nozzle hole is inclined so as to move away from the valve hole axis toward the downstream side, and in each fuel nozzle hole group, the outer fuel nozzle holes farther from the center of the group are formed with a smaller diameter than the central fuel nozzle holes closer to the center of the group, and the deflection angle of the outer fuel nozzle holes with respect to the bisector is set larger than the pitch angle between the fuel nozzle holes. [Effects of the Invention]

[0011] According to a first feature of the present invention, when the valve body opens, the fuel that flows down the multiple fuel passages passes through the valve seat, joins in the annular fuel collection chamber, passes through the valve hole, and is then radially diffused in the fuel diffusion chamber before being injected to the outside from the multiple fuel nozzle holes. Because the path from the fuel passages to the fuel nozzle holes is sufficiently long, the fuel that flows down the multiple fuel passages is sufficiently mixed before reaching the fuel nozzle holes, eliminating streamlines. Furthermore, by having more fuel nozzle holes than fuel passages and including multiple fuel nozzle holes that are not in phase with the fuel passages, the fuel injection state from each fuel nozzle hole can be stabilized without the need for phasing between the fuel passages and the fuel nozzle holes, and the spray form formed by the injected fuel can be stabilized.

[0012] According to the second feature of the present invention, the valve guide hole is forged to have a cross-sectional polygonal shape with 4 to 6 interior corners, so that multiple fuel passages surrounding the spherical valve portion can be easily formed together with the valve seat member valve without performing special cutting processing on the spherical valve portion and the valve guide hole, thereby contributing to reducing manufacturing costs.

[0013] According to a third feature of the present invention, a plurality of fuel nozzle holes are grouped into a first fuel nozzle hole group consisting of a plurality of fuel nozzle holes arranged on one semicircle of an imaginary circle divided by a bisector, and a second fuel nozzle hole group consisting of a plurality of fuel nozzle holes arranged on the other semicircle of the imaginary circle, the hole axis of each fuel nozzle hole is inclined so as to move away from the valve hole axis toward the downstream side, and in each fuel nozzle hole group, the outer fuel nozzle holes are formed with a smaller diameter than the central fuel nozzle hole, and the deflection angle of the outer fuel nozzle holes with respect to the bisector is set larger than the pitch angle between the fuel nozzle holes.As a result, the collective spray form emitted from each fuel nozzle hole group is formed to gather at the center of the form, and the first collective spray form emitted from the first fuel nozzle hole group and the second collective spray form emitted from the second fuel nozzle hole group can be directed in two directions forming an inverted V shape. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a vertical cross-sectional view showing an embodiment of an electromagnetic fuel injection valve for an engine according to the present invention. [Figure 2] FIG. 2 is an enlarged view of the portion indicated by arrow 2 in FIG. 1 (an enlarged cross-sectional view taken along line 2-2 in FIG. 3). [Figure 3] FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line 4-4 in FIG. [Figure 5] FIG. 5 is a side view of the collected spray foam as seen from the direction of arrow 5 in FIG. [Figure 6] FIG. 6 is a front view of the collected spray foam as seen from the direction of arrow 6 in FIG. [Explanation of symbols]

[0015] I...Fuel injection valve Aa: Axis of the central fuel nozzle Ab: Outer fuel nozzle hole axis C: Virtual circle Ca...One semicircle Cb...the other semicircle L...Bisector O...Group center Y: Valve hole axis 2. Valve housing 3. Valve seat member 7. Valve hole 8. Valve seat 9. Valve guide hole 9a...Plane part 9b...Inner corner 10 Nozzle plate 11. Fuel nozzle 13. Valve body 14. Spherical valve section 17A...1st fuel nozzle group 17B...Second fuel nozzle group 17a...Fuel nozzle hole (center fuel nozzle hole) 17b...Fuel nozzle hole (outer fuel nozzle hole) 37...Fuel passage 49...Fuel assembly room 50 Fuel diffusion chamber DETAILED DESCRIPTION OF THE INVENTION

[0016] 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.

[0017] 1, a mounting hole 41 that opens into a combustion chamber 42 is provided in a cylinder head 40 of an engine E, and an electromagnetic fuel injection valve I that can inject fuel into the combustion chamber 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 cylinder head 40.

[0018] 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.

[0019] The valve seat member 3 is provided with a conical valve seat 8 , a valve hole 7 penetrating the center of the valve seat 8 , and a valve guide hole 9 communicating with the large diameter portion of the valve seat 8 .

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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 upper 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 fitting depth of the retainer 23 into the fixed core 5.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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).

[0028] Next, the structure of the valve seat member 3 will be described in detail with reference to FIGS.

[0029] The valve guide hole 9 provided in the valve seat member 3 has a cross-sectional regular polygonal shape (a regular hexagonal shape in the illustrated example) with four to six interior corners 9b, and is formed so as to extend rearward from the large-diameter portion of the conical valve seat 8 along the valve hole axis Y (which is also the axis of the valve housing 2). That is, the valve guide hole 9 in the illustrated example is composed of six flat surfaces 9a and six interior corners 9b of the same width, alternately arranged to surround the valve hole axis Y, and the six flat surfaces 9a serve as guide surfaces that guide the lifting and lowering of the spherical valve portion 14, i.e., the opening and closing operations. In addition, a plurality of fuel passages 37 connected to the valve seat 8 are defined between the six interior corners 9b and the spherical valve portion 14. Note that, to ensure that the spherical valve portion 14 is properly seated on the conical valve seat 8 when the valve disc 13 is closed, minute gaps are provided between the spherical valve portion 14 and each flat surface 9a.

[0030] The valve seat member 3 is provided with an annular fuel collecting chamber 49 that connects the valve seat 8 and the valve hole 7. The bottom surface of the fuel collecting chamber 49 is formed by a concave curved surface 49a.

[0031] Furthermore, the valve seat member 3 is provided with a guide hole 16 that extends in a tapered shape from the rear edge of the valve guide hole 9 toward the rear thereof. This guide hole 16 has the function of guiding the spherical valve portion 14 into the valve guide hole 9 when the fuel injection valve I is assembled.

[0032] The valve guide hole 9, the valve seat 8, the concave curved surface 49a and the guide hole 16 are formed when the valve seat member 3 is forged.

[0033] 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.

[0034] A nozzle plate 10 made of steel plate is liquid-tightly welded to the front end surface of the valve seat member 3, and a flat fuel diffusion chamber 50 with a diameter significantly larger than that of the valve hole 7 is provided between this nozzle plate 10 and the valve seat member 3. In the illustrated example, this fuel diffusion chamber 50 is configured by a shallow circular recess 50a formed in the front end surface of the valve seat member 3 being covered by the nozzle plate 10.

[0035] The inner peripheral surface of the valve hole 7 is a convex curved surface 7 a that smoothly continues to the bottom surface of the fuel collection chamber 35 and the ceiling surface of the fuel diffusion chamber 50 .

[0036] As shown in Figures 2 and 4, the nozzle plate 10 is provided with a plurality of fuel nozzle holes 17a, 17b which are larger in diameter than the valve hole 7, are arranged on an imaginary circle C concentric therewith, and open into the fuel diffusion chamber 50.

[0037] The number of the plurality of fuel nozzle holes 17a, 17b is greater than the number of the plurality of fuel passages 37, and includes a plurality of fuel nozzle holes 17a, 17b that are not in phase with the fuel passages 37. In the illustrated example, there are six fuel passages 37 and eight fuel nozzle holes 17a, 17b, and all of these eight fuel nozzle holes 17a, 17b are out of phase with the six fuel passages 37.

[0038] Furthermore, the imaginary circle C is divided into one semicircle Ca and the other semicircle Cb by an arbitrary bisector L, and half of all fuel nozzle holes 17a, 17b, i.e., four fuel nozzle holes 17a, 17b, are arranged on one semicircle Ca and the other semicircle Cb. The four fuel nozzle holes 17a, 17b on one semicircle Ca form a first fuel nozzle hole group 17A, and the four fuel nozzle holes 17a, 17b on the other semicircle Cb form a second fuel nozzle hole group 17B. In these first and second fuel nozzle hole groups 17A, 17B, the fuel nozzle holes 17a closest to the group center O (i.e., the center of each semicircle Ca, Cb) are called central fuel nozzle holes 17a, and the fuel nozzle holes 17b farthest from the group center O are called outer fuel nozzle holes 17b.

[0039] 2, all fuel nozzle holes 17a, 17b are formed with their respective hole axes Aa, Ab inclined downstream in a direction away from valve hole axis Y. In this case, as in the illustrated example, it is desirable to set the inclination angle θ2 of the hole axis Ab of outer fuel nozzle hole 17a larger than the inclination angle θ1 of the hole axis Aa of central fuel nozzle hole 17a.

[0040] Furthermore, the diameter d of the outer fuel nozzle hole 17b is set smaller than the diameter D of the central fuel nozzle hole 17a.

[0041] Furthermore, as shown in FIG. 4, in the first and second fuel nozzle hole groups 17A, 17B, the deflection angle β of the outer fuel nozzle holes 17b with respect to the bisector L is set to be larger than the pitch angle α between the fuel nozzle holes 17a, 17b.

[0042] Next, the operation of this embodiment will be described.

[0043] 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.

[0044] When the coil 30 is energized, a magnetic flux generated by the coil 30 passes sequentially through the fixed core 5, the coil housing 31, the magnetic cylinder 4, and the movable core 12, and the magnetic force attracts the movable core 12 together with the valve element 13 to the fixed core 5 against the set load of the valve spring 22, causing the spherical valve portion 14 of the valve element 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 the valve seat 8, joins together in the annular fuel collection chamber 49, passes through the valve hole 7, and is then injected to the outside from the multiple fuel nozzle holes 17a, 17b while diffusing radially in the fuel diffusion chamber 50. In this way, because the path from each fuel passage 37 to the fuel nozzle holes 17a, 17b is sufficiently long, the fuel that flows down the multiple fuel passages 37 is sufficiently mixed before reaching the fuel nozzle holes 17a, 17b, causing the flow lines to disappear. Furthermore, by having more fuel nozzle holes 17a, 17b than fuel passages 37 and including multiple fuel nozzle holes 17a, 17b that are not in phase with fuel passage 37, it is possible to stabilize the fuel injection state from each fuel nozzle hole 17a, 17b and stabilize the spray forms fa, fb while eliminating the need to align the phase between fuel passage 37 and fuel nozzle holes 17a, 17b. This contributes to improved fuel efficiency and output performance of the engine and also contributes to improved mass productivity by eliminating the need for high processing precision and assembly precision for the components.

[0045] Furthermore, since the valve guide hole 9 is forged together with the valve seat member 3 so as to have a regular polygonal cross section with 4 to 6 interior corners 9b, it is possible to easily form multiple fuel passages 37 in the valve seat member 3 without performing special cutting processing on the spherical valve portion 14 and the valve guide hole 9, which contributes to reducing manufacturing costs.

[0046] Furthermore, the multiple fuel nozzle holes 17a, 17b are grouped into a first fuel nozzle hole group 17A consisting of the multiple fuel nozzle holes 17a, 17b arranged on one semicircle Ca of the imaginary circle C, and a second fuel nozzle hole group 17B consisting of the multiple fuel nozzle holes 17a, 17b arranged on the other semicircle Cb of the imaginary circle C. In the first and second fuel nozzle hole groups 17A, 17B, the outer fuel nozzle holes 17b are formed with a smaller diameter than the central fuel nozzle holes 17a, and the deflection angle β of the outer fuel nozzle holes 17b with respect to the bisector L is set to be larger than the pitch angle α between the fuel nozzle holes 17a, 17b. As a result, the first and second fuel nozzle hole groups 17A, 17B are each concentrated toward the center O of their respective groups, and the first and second concentrated spray forms F1, F2 emitted from the first and second fuel nozzle hole groups 17A, 17B are each concentrated at the center of each form, as shown in FIG. 5. That is, the relatively narrow spray forms fb (see Figure 2) emitted from the small diameter outer fuel nozzle holes 17b on either side of the large diameter central fuel nozzle hole 17a act to suppress the spread of the relatively wide spray form fa (see Figure 2), so that the first and second collected spray forms F1, F2 gather at the center of each form, as shown in Figure 5.

[0047] Furthermore, in the first and second fuel nozzle hole groups 17A, 17B, the hole axes Aa, Ab of all fuel nozzle holes 17a, 17b are inclined downstream away from their respective valve hole axes Y, so that, as shown in Figure 6, the first collective spray form F1 emitted from the first fuel nozzle hole group 17A and the second collective spray form F2 emitted from the second fuel nozzle hole group 17B are directed in two directions forming a symmetrical inverted V shape.

[0048] In this case, in each fuel nozzle hole group 17A, 17B, setting the inclination angle β of the hole axis Ab of the outer fuel nozzle hole 17a larger than the inclination angle α of the hole axis Aa of the central fuel nozzle hole 17a is effective in more effectively suppressing the spread of the spray form fa emitted from the central fuel nozzle hole 17a by the spray form fb emitted from the outer fuel nozzle hole 17b.

[0049] As a result, the first and second collective spray forms F1, F2 can be accurately supplied toward a pair of branch ports that form the downstream portion of the engine's intake port, thereby minimizing fuel adhesion to the walls of each branch port, thereby contributing to improved fuel efficiency and output performance of the engine.

[0050] 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.

[0051] For example, the valve guide hole 9 can be formed cylindrically, and multiple flat surfaces can be formed on the circumferential surface of the spherical valve portion 14, so that the flat surfaces and the inner circumferential surface of the valve guide hole define multiple fuel passages 37 surrounding the spherical valve portion 14.

Claims

1. The valve housing (2) has a valve seat member (3) at its front end, the valve seat member (3) having a conical valve seat (8) and a valve hole (7) penetrating the center of the valve seat (8); a nozzle plate (10) joined to the end of the valve seat (8) and having a plurality of fuel nozzle holes (17a, 17b); a valve body (13) having a spherical valve portion (14) at its front end for opening and closing the valve hole (7) in cooperation with the valve seat (8); and an electromagnetic actuator (11) for applying an opening action to the valve body (13) when energized. The valve seat member (3) has a fuel passage (37) and a guide for guiding the opening and closing action of the valve body (13). an annular fuel collection chamber (49) provided between the valve seat (8) and the valve hole (7), the fuel collection chamber (49) having an inner surface (9a) and the valve guide hole (9); and a flat fuel diffusion chamber (50) having a diameter larger than the valve hole (7), the fuel diffusion chamber having an outlet of the valve hole (7) opening between the valve seat member (3) and the nozzle plate (10) joined to the front end surface of the valve seat member (3), the fuel injection holes (17a, 17b) opening into the fuel diffusion chamber (50) being arranged in the nozzle plate (10) at a radial distance from the valve hole (7), the fuel passage (37) is defined in plurality in the valve guide hole (9) so as to surround the spherical valve portion (14) and be connected to the valve seat (8), the number of the fuel nozzle holes (17a, 17b) is greater than the number of the fuel passages (37), and the plurality of fuel nozzle holes (17a, 17b) are not in phase with the fuel passages (37); The plurality of fuel nozzle holes (17a, 17b) are arranged on an imaginary circle (C) centered on the valve hole axis (Y), and the fuel nozzle holes (17a, 17b) are grouped into a first fuel nozzle hole group (17A) consisting of the plurality of fuel nozzle holes (17a, 17b) arranged on one semicircle (Ca) of the imaginary circle (C) divided by a bisector (L), and a second fuel nozzle hole group (17B) consisting of the plurality of fuel nozzle holes (17a, 17b) arranged on the other semicircle (Cb) of the imaginary circle (C), and each fuel nozzle hole (17 the hole axes (Aa, Ab) of the outer fuel injection holes (17a, 17b) are inclined so as to move away from the valve hole axis (Y) downstream thereof, the outer fuel injection holes (17b) farther from the group center (O) of each fuel injection hole group (17A, 17B) are formed to have a smaller diameter than the central fuel injection holes (17a) that are closer to the group center (O), and the deflection angle (β) of the outer fuel injection holes (17b) with respect to the bisector (L) is set to be larger than the pitch angle (α) between the fuel injection holes (17a, 17b).

2. 2. The electromagnetic fuel injection valve according to claim 1, The valve guide hole (9) is forged to have a cross-sectional polygonal shape with four to six sides, the cross-sectional shape being composed of the guide surface portion (9a) and the inner corner portion (9b), 10. An electromagnetic fuel injection valve, comprising: a fuel passage defined by the guide surface portion (9a) and the inner angle portion (9b).

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