JP2013234598A - Fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain spray pattern collapse and spray characteristics irregularity when starting spraying and to restrain penetration decline of a spray fuel at the same time.SOLUTION: A fuel injection valve comprises a needle 30 stored inside a body 20 with a nozzle hole 24 formed. A sack chamber 23 is formed inside the body 20 for gathering a fuel distributed annularly in a fuel passage 21 between the needle 30 and the body 20 for guiding the same to a nozzle hole 24. A conical part 33 is formed in a part downstream of a sheet surface 32 of the needle 30 elongating in the needle axis direction while being tapered toward the sack chamber 23. A projection part 34 is formed further at the top end of the conical part 33 elongating in the needle axis direction in a shape with a smaller tapering degree.

Description

  The present invention relates to a fuel injection valve that injects fuel to be burned in an internal combustion engine.

  As shown in FIG. 10, the conventional fuel injection valve disclosed in Patent Document 1 and the like is configured by accommodating a needle 30x inside a body 20 in which an injection hole 24 is formed. When the seat surface 32 of the needle 30x is seated on the seating surface 22 formed inside the body 20, the annular fuel passage 21 formed between the needle 30x and the body 20 is blocked, Fuel injection is stopped (see FIG. 10A). When the seat surface 32 is separated from the seating surface 22, the fuel passage 21 is opened and fuel is injected from the injection hole 24 (see FIG. 10B).

  Further, a sac chamber 23 is formed inside the body 20, and the fuel distributed annularly in the fuel passage 21 is collected in the sac chamber 23 and then guided to the injection hole 24. Hereinafter, the technical significance of providing the sack chamber 23 will be described.

  Strictly speaking, when the needle 30x is separated from the seat surface 32, the needle 30x is seated in a tilted state, and therefore the annular fuel passage 21 is not simultaneously opened over the entire circumference. For this reason, if the sac chamber 23 is abolished by forming the injection holes 24L and 24R at the positions indicated by alternate long and short dash lines in the figure, the injection starts from the injection hole 24L located in the vicinity of the first opened portion. Thereafter, the injection is started from the other nozzle holes 24R. That is, the spray pattern injected from the fuel injection valve into the combustion chamber does not become a desired pattern at the start of injection. Moreover, since the spray characteristics (for example, injection length and injection width) of the fuel injected earlier and the spray characteristics of the fuel injected later are different, the combustion state is deteriorated.

  On the other hand, according to the configuration of FIG. 10 in which the injection hole 24 is formed at the solid line position in the drawing and the sac chamber 23 is provided, the fuel flowing out from the annular fuel passage 21 is injected into the sac chamber 23 after being collected. Since injection is performed from the holes 24, it is urged to start injection from the plurality of injection holes 24 at the same time. Therefore, it is possible to suppress the spray pattern from collapsing at the start of injection or the spray characteristics to vary between the nozzle holes.

JP-A-8-144895

  However, the inventors have found that the formation of the sac chamber 23 newly causes the following problems.

  That is, it is ideal that the fuel flowing from the fuel passage 21 into the sac chamber 23 flows into the nozzle hole 24 at the shortest distance as shown by an arrow F1 in FIG. A part of the fuel that flows into the nozzle hole 24 flows around the bottom surface 23a of the sac chamber 23 as shown by an arrow F2. Then, as shown by the arrow F3, a swirling flow is generated in the nozzle hole 24, and this causes a decrease in penetration force (penetration) of the injected fuel, leading to deterioration of exhaust emission such as smoke increase. I understood.

  The present invention has been made in view of the above problems, and its purpose is a fuel injection valve that achieves both suppression of spray pattern collapse and spray characteristic variation at the start of injection, and suppression of a decrease in penetrating force of the injected fuel. Is to provide.

  The invention for achieving the above object is characterized by the following points. That is, a body having an injection hole for injecting fuel to be burned by an internal combustion engine and a needle housed in the body are provided, and a seat surface of the needle is seated on a seating surface formed in the body. By blocking the annular fuel passage formed between the needle and the body, stopping fuel injection from the injection hole, and separating the seat surface from the seating surface, It is assumed that the fuel injection valve opens the fuel passage and injects fuel from the injection hole.

  And, a sac chamber located between the fuel passage and the nozzle hole and collecting fuel distributed annularly in the fuel passage and leading to the nozzle hole is formed inside the body, A conical portion extending in the axial direction while being tapered toward the sac chamber is formed in a portion of the needle downstream of the seat surface, and the degree of taper is formed at the tip of the conical portion. A protrusion extending in the axial direction is formed in a shape with a small (small taper angle).

  In short, in the above invention, a conical portion that is tapered toward the sac chamber is formed at the tip portion of the needle, and the tip portion of the cone portion has a shape with a reduced degree of taper (small taper angle). A protrusion is formed. Therefore, the fuel flowing into the sac chamber along the wall surface of the conical portion from the fuel passage is bent into a flow toward the nozzle hole by the wall surface of the protruding portion having a reduced taper degree (FIGS. 2 and 7 to FIG. 9 (see arrows F4, F5, F6, and F7). Therefore, the flow which goes to the bottom face of the sac chamber and then toward the nozzle hole is suppressed, and as a result, the swirl flow generated in the nozzle hole can be reduced. Therefore, it is possible to suppress a decrease in the penetration force of the injected fuel due to the formation of the sac chamber.

  Further, since the sac chamber is formed, the fuel distributed annularly in the fuel passage collects in the sac chamber and then flows into the nozzle hole. Therefore, it is promoted that injection is simultaneously started from a plurality of nozzle holes. Therefore, it is possible to suppress the spray pattern from collapsing at the start of injection or the spray characteristics to vary between the nozzle holes.

  As described above, according to the present invention, by forming the sack chamber, it is possible to suppress the spray pattern collapse and the spray characteristic variation at the start of injection, and also to suppress the decrease in the penetration force of the injected fuel by forming the protrusion. it can.

1 is a layout diagram of an engine on which a fuel injection valve according to a first embodiment of the present invention is mounted. Sectional drawing of the fuel injection valve concerning 1st Embodiment. The test result which shows the time change of the spray length of the fuel injected from a fuel injection valve. The test result which shows the relationship between the distance from the inlet of a nozzle hole to a needle, and spray length. The test result which shows the time change of the spray width of the fuel injected from a fuel injection valve. The test result which shows the relationship between the distance from the inlet of a nozzle hole to a needle, and the spray width. Sectional drawing of the fuel injection valve concerning 2nd Embodiment of this invention. Sectional drawing of the fuel injection valve concerning 3rd Embodiment of this invention. Sectional drawing of the fuel injection valve concerning 4th Embodiment of this invention. Sectional drawing explaining the structure of the conventional fuel injection valve.

  Hereinafter, embodiments in which a fuel injection valve according to the present invention is applied to an internal combustion engine mounted on a vehicle will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are denoted by the same reference numerals in the drawings, and the description of the same reference numerals is used.

(First embodiment)
The internal combustion engine 10 shown in FIG. 1 is a compression ignition type, and a fuel injection valve 12 is mounted at a position where fuel is directly injected into the combustion chamber 11. The fuel injected from the fuel injection valve 12 is high-pressure (for example, several hundred MPa) fuel pumped from the fuel pump 14 and accumulated in the common rail 13.

  FIG. 2 is a cross-sectional view showing a tip portion of the fuel injection valve 12. The fuel injection valve 12 includes a body 20 having a plurality of injection holes 24 and a needle 30 accommodated in the body 20. It is prepared for. A tip portion of the body 20 where the injection hole 24 is formed is disposed so as to be exposed to the combustion chamber 11, and the fuel injected from the injection hole 24 burns in the combustion chamber 11.

  The operation of an electric actuator (for example, an electromagnetic coil or a piezoelectric element) mounted on the fuel injection valve 12 is controlled by the electronic control unit (ECU 15) shown in FIG. When the valve is opened, fuel is injected from the nozzle hole 24. On the other hand, when the needle 30 is lifted down in the body 20 and the valve is closed, fuel injection from the nozzle hole 24 is stopped.

  More specifically, the body 20 is formed in a cylindrical shape, and the needle 30 is formed in a columnar shape extending in the vertical direction (axial direction) in FIG. When the needle 30 is lifted down in the axial direction as shown in FIG. 2A, the seat surface 32 formed on the outer peripheral surface of the needle 30 is seated on the seating surface 22 formed on the inner peripheral surface of the body 20. . As a result, the annular fuel passage 21 formed between the needle 30 and the body 20 is blocked, and fuel injection from the injection hole 24 is stopped. On the other hand, when the needle 30 is lifted up in the axial direction as shown in FIG. 2B, the seat surface 32 is separated from the seating surface 22, whereby the fuel passage 21 is opened and fuel is injected from the injection hole 24. .

  A sac chamber 23 is formed in the body 20 at the downstream side of the fuel passage 21 to collect fuel distributed annularly in the fuel passage 21 and guide it to the nozzle holes 24. The sac chamber 23 has a hemispherical shape, and a plurality of nozzle holes 24 are formed at an equal pitch in a portion of the body 20 where the sac chamber 23 is formed.

  The needle 30 has a main body portion 31 that forms a fuel passage 21 with the body 20. On the downstream side of the main body 31, a portion forming the sheet surface 32 is continuous. Further, a conical portion 33 is connected to the downstream side of the seat surface 32, and a protruding portion 34 is connected to the downstream side of the conical portion 33.

  The portion of the needle 30 that forms the seat surface 32 and the conical portion 33 have a conical shape that tapers toward the downstream side. Hereinafter, the apex angle of the cone, that is, the taper angle is referred to as a taper angle, and the taper angle is defined to be smaller as the taper angle is smaller. The taper angle of the conical portion 33 is set larger than the taper angle of the seat surface 32. Since the projecting portion 34 has a cylindrical shape, it is a shape that is neither tapered nor tapered, but it can be said that the degree of tapering is smaller than that of the conical portion 33.

  2A in which the needle 30 is seated on the seating surface 22, the boundary between the seat surface 32 and the conical portion 33 (the upper end of the conical portion 33) is located upstream of the sac chamber 23. Here, the technical significance of such positional relationship will be described below.

  Since the needle 30 repeatedly collides with the seating surface 22 of the body 20, the seating surface 22 is slightly deformed into a concave shape. Then, the downstream portion of the seating surface 22 of the body 20 is deformed into a convex shape by the amount of deformation (see the dotted line 20a in FIG. 2B). For this reason, when the upper end of the conical portion 33 is positioned downstream of the downstream portion 20 a, the seat surface 32 is seated on the convex portion 20 a and is not seated on the seating surface 22. Then, the sealing performance between the needle 30 and the body 20 is deteriorated, and there is a problem that the fuel passage 21 cannot be completely blocked.

  In this embodiment in view of this point, since the upper end of the conical portion 33 having a large taper angle is configured to be located upstream of the sack chamber 23 when seated, the seat surface 32 is formed on the convex portion 20a. You can avoid sitting. Therefore, the problem that the fuel passage 21 cannot be completely blocked can be solved.

  The boundary between the conical portion 33 and the protruding portion 34 (the lower end of the conical portion 33) in both the state of FIG. 2B in which the needle 30 is separated from the seating surface 22 and lifted to the maximum extent and the seating state. ) Is located in the sack chamber 23. Further, the tip of the protrusion 34, that is, the lower end 30 b of the needle 30 is located closer to the bottom surface 23 a of the suck chamber 23 than the center line C of the injection hole 24 in the maximum lift-up state. Further, the boundary between the conical portion 33 and the protruding portion 34 is located on the opposite side of the bottom surface 23a with respect to the center line C of the nozzle hole 24 in the maximum lift-up state, and on the bottom surface 23a side with respect to the center line C in the seated state. Located in.

  As described above, according to the present embodiment, the protruding portion 34 having a columnar shape (a shape with a reduced degree of taper) is provided at the tip of the tapered cone portion 33. Therefore, the fuel that has flowed into the sac chamber 23 along the wall surface of the conical portion 33 from the fuel passage 21 is bent toward the inlet of the injection hole 24 by the outer peripheral wall surface of the projecting portion 34 (arrow in FIG. 2B). See F4). Therefore, the flow (refer to the arrow F2 in FIG. 10B) that goes around the bottom surface 23a of the sac chamber 23 and then toward the inlet of the nozzle hole 24 is suppressed, and as a result, the swirl flow generated in the nozzle hole 24 ( The arrow F3 in FIG. 10B can be reduced. Therefore, the pressure loss in the injection hole 24 is reduced, the penetration force of the injected fuel is improved, and the exhaust emission such as the reduction of smoke contained in the exhaust can be improved.

  In particular, since the penetration force at the beginning of injection can be improved, the effect of improving the combustion state when injecting a small amount of fuel that is closed immediately after the start of injection (for example, in the case of pilot injection) is exhibited. Therefore, improvement of exhaust emission is promoted.

  Hereinafter, based on the test results conducted by the present inventors, the effect of improving the penetration force described above will be described.

  The horizontal axis in FIG. 3 indicates the elapsed time, the vertical axis indicates the spray length from the outlet of the nozzle hole 24, and the spray length increases after the injection is started. In addition, the horizontal axis in FIG. 5 indicates elapsed time, the vertical axis indicates the maximum spray width, and the spray width increases after the injection is started. 3 and FIG. 5 are the test results in the case of the conventional structure shown in FIG. 10, the alternate long and short dash line is in the case of the present embodiment, and the dotted line is the test result in the case of the second embodiment to be described later. This test result shows that according to the present embodiment having the protrusion 34, the spray length is longer and the spray width is smaller than the conventional structure not having the protrusion 34. Means improved penetration.

  3 and FIG. 5 correspond to the maximum spray length and the maximum spray width at the time of pilot injection, and the spray length and the spray width at time t1 and t2 are shown in FIG. 4 and FIG. 4 and 6, the horizontal axis represents the sack diameter ratio described later, and the vertical axis represents the spray length from the outlet of the nozzle hole 24. The “sack diameter ratio” is a ratio of a distance L1 (see FIG. 2A) from the needle 30 to the nozzle hole 24 inlet with respect to the diameter D of the sack chamber 23 (see FIG. 2B). The “distance L1” is a distance from the nozzle hole inlet 24 to the needle surface 30a on the center line C of the nozzle hole 24 in the seated state. In the present embodiment, the position where the center line C intersects the needle surface 30a is the conical portion 33.

  In FIG. 4 and FIG. 6, the triangle mark indicates the test result in the case of the conventional structure, the circle mark indicates the test result in the case of the present embodiment, and the square mark indicates the test result in the case of the second embodiment. The distance Lx is shorter than the distance Lx (see FIG. 10A), and the distance L2 in the second embodiment is shorter than the distance L1 in the present embodiment. The sack diameter ratio of the present embodiment is 35%, which is smaller than the sack diameter ratio of 39% of the conventional structure, and the sac diameter ratio of the second embodiment (about 21%) is greater than the sack diameter ratio of the present embodiment. Is also small.

  Therefore, the test results in FIG. 4 and FIG. 6 indicate that the spray length is increased and the spray width is reduced by shortening the distance from the nozzle hole inlet to the needle surface to reduce the sack diameter ratio. Yes. Specifically, in the pilot injection region, this embodiment shows that the spray length is 18% longer and the spray width is 10% shorter than the conventional structure. This means improved penetration.

  Further, the test results of FIGS. 4 and 6 show that the inclination of the spray length and the spray width with respect to the sac diameter ratio changes greatly with the sack diameter ratio of 35% as a boundary, and when the sack diameter ratio becomes larger than 35%, the spray length increases. It shows that the spray width becomes shorter and the spray width becomes larger. Therefore, it is desirable to configure the sack diameter ratio to be 35% or less from the viewpoint of improving penetration.

  Next, the effect by providing the sack chamber 23 will be described. The fuel distributed annularly in the fuel passage 21 gathers in the sac chamber 23 and is then distributed to the plurality of nozzle holes 24. Therefore, it is promoted that the injection is simultaneously started from the plurality of nozzle holes 24. Therefore, it is possible to suppress the spray pattern from collapsing at the start of injection or the spray characteristics to vary between the nozzle holes 24.

  As described above, according to the present embodiment, by forming the sack chamber 23, it is possible to suppress the spray pattern collapse and the spray characteristic variation at the start of injection, and by forming the protrusion 34, the penetration power of the injected fuel can be suppressed. The decrease can be suppressed. Further, in the present embodiment, since the protruding portion 34 is formed in a columnar shape, the processing of the protruding portion 34 is simplified as compared with the case where the protruding portion 35 is formed in a conical shape as shown in FIG.

(Second Embodiment)
In the needle 30 according to the first embodiment, the protruding portion 34 is formed in a cylindrical shape. On the other hand, in the needle 30A of the present embodiment shown in FIG. 7, the protruding portion 35 is formed in a conical shape extending from the tip of the conical portion 32 while tapering in the axial direction of the needle 30A. The taper angle of the conical portion 33 is set larger than the taper angle of the seat surface 32, and the taper angle of the protruding portion 35 is set smaller than the taper angle of the conical portion 33 (the degree of taper is small). The tip of the cone is formed on a flat surface perpendicular to the axial direction.

  Further, in the maximum lift-up state shown in FIG. 7B, the boundary between the conical portion 33 and the projecting portion 35 (the lower end of the conical portion 33) is located upstream of the sack chamber 23. On the other hand, in the sitting state shown in FIG. 7A, the boundary between the conical portion 33 and the protruding portion 35 is located in the sack chamber 23. Further, the tip of the protruding portion 35, that is, the lower end 30 b of the needle 30 </ b> A is located closer to the bottom surface 23 a of the sack chamber 23 than the center line C of the nozzle hole 24 in the maximum lift-up state. The boundary between the conical portion 33 and the protruding portion 34 is located on the opposite side of the bottom surface 23a with respect to the center line C of the nozzle hole 24 in both the maximum lift-up state and the seated state.

  As described above, according to the present embodiment, the conical protrusion 35 with a reduced degree of taper is provided at the tip of the tapered conical portion 33. Therefore, the fuel that has flowed into the sac chamber 23 along the wall surface of the conical portion 33 from the fuel passage 21 is bent toward the inlet of the injection hole 24 by the outer peripheral wall surface of the projecting portion 35 (arrow in FIG. 7B). See F5). Therefore, the flow which goes around to the bottom face 23a of the sac chamber 23 and goes to the inlet of the injection hole 24 is suppressed, and as a result, the swirl flow generated in the injection hole 24 can be reduced. Therefore, the pressure loss in the injection hole 24 is reduced, and the penetration force of the injected fuel can be improved.

  Here, in 1st Embodiment which made the protrusion part 34 the cylinder shape, if the cylinder diameter of the protrusion part 34 is enlarged, since the distance L1 will become short, penetration force improvement can be gasified. However, if the cylinder diameter is excessively large, the corner of the needle lower end 30b comes into contact with the sack chamber bottom surface 23a in the seated state, so there is a limit to increasing the cylinder diameter. On the other hand, in the present embodiment in which the projecting portion 35 has a conical shape, the limit of increasing the conical diameter of the projecting portion 35 to shorten the distance L2 is loose compared to the case of the cylindrical shape. Is advantageous.

  Therefore, in the present embodiment in which the projecting portion 35 has a conical shape, the cone diameter of the projecting portion 35 can be increased to promote the distance L2, and the reduction of the sack diameter ratio can be promoted. As can be seen from the above, the penetration force can be improved as compared with the first embodiment.

(Third embodiment)
In the needle 30B of the present embodiment shown in FIG. 8, a columnar protruding portion 36 similar to the protruding portion 34 according to the first embodiment is formed, and the tip of the protruding portion 36 is tapered toward the needle axis direction while being tapered. An extending flare portion 36a is formed. In other words, it can be said that the taper angle of the flare portion 36a is negative. The flare portion 36a may have a conical shape in which the ridge line of the outer peripheral surface extends in a straight line, or may have a shape in which the outer peripheral surface is curved toward the injection hole inlet as shown in FIG.

  According to the present embodiment, a conical protrusion 36 with a reduced degree of taper is provided at the tip of the tapered cone 33, and a flare 36 a that is tapered is formed at the tip of the protrusion 36. Yes. Therefore, the fuel that has flowed into the sac chamber 23 along the wall surface of the conical portion 33 from the fuel passage 21 is bent toward the nozzle hole inlet along the outer peripheral wall surface of the projecting portion 36, and then injected by the flare portion 36 a. It is bent toward the hole inlet (see arrow F6 in FIG. 8B). Therefore, the flow which goes around to the bottom face 23a of the sac chamber 23 and goes to the inlet of the injection hole 24 is suppressed, and as a result, the swirl flow generated in the injection hole 24 can be reduced. Therefore, the pressure loss in the injection hole 24 is reduced, and the penetration force of the injected fuel can be improved.

(Fourth embodiment)
In each of the above embodiments, the taper angle of the conical portion 33 formed on the downstream side of the seat surface 32 is made larger than the taper angle of the seat surface 32. In contrast, in the needle 30 </ b> C of the present embodiment shown in FIG. 9, the taper angle of the conical portion 33 is the same as the taper angle of the seat surface 32. That is, the conical portion 33 is formed by extending the seat surface 32 to the downstream side. And the protrusion part 34 is formed in the front-end | tip of the cone part 33. As shown in FIG.

  Also in this embodiment, the fuel that has flowed into the sac chamber 23 from the fuel passage 21 along the wall surface of the conical portion 33 is bent toward the inlet of the injection hole 24 by the outer peripheral wall surface of the protrusion 34 (FIG. 9B). ) See arrow F7 in the middle). Therefore, the flow which goes around to the bottom face 23a of the sac chamber 23 and goes to the inlet of the injection hole 24 is suppressed, and as a result, the swirl flow generated in the injection hole 24 can be reduced. Therefore, the pressure loss in the injection hole 24 is reduced, and the penetration force of the injected fuel can be improved.

(Other embodiments)
The present invention is not limited to the description of the above embodiment, and may be modified as follows. Moreover, you may make it combine the characteristic structure of each embodiment arbitrarily, respectively.

  -Although the cone part 33 of each said embodiment is a shape where an outer peripheral surface extends on a straight line, the shape curved along the flow F4-F7 which goes to the nozzle hole 24 may be sufficient.

  -In the said 3rd Embodiment, although the flare part 36a is formed in the column-shaped protrusion part 36, you may form the flare part 36a in the cone-shaped protrusion part 35 shown in FIG.

  In each of the above embodiments, the lower end 30b of the needle 30 is configured to be positioned closer to the bottom surface 23a of the sac chamber 23 than the center line C of the nozzle hole 24 in the maximum lift-up state. On the other hand, you may comprise so that a part of lower end 30b of the needle 30 may be located in the other side of the bottom face 23a with respect to the centerline C in the maximum lift up state.

  -In the said 1st Embodiment, you may comprise so that the boundary position of the cone part 33 and the protrusion part 34 may be located in the upstream of the sack chamber 23 in a seating state. Moreover, in the said 2nd Embodiment, you may comprise so that the boundary position of the cone part 33 and the protrusion part 35 may be located in the suck | suck chamber 23 in a seating state.

  In each of the above embodiments, the protrusions 34, 35, 36 are formed in a cylindrical or conical shape, and the taper angle is set to zero or plus, but the protrusions are tapered so that the taper angle becomes negative. You may make it the shape. In other words, the projecting portion 36 may be eliminated in the third embodiment, the flare portion 36a may be formed at the lower end of the conical portion 33, and the flare portion 36a may function as the projecting portion.

  DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 21 ... Fuel passage, 22 ... Seating surface, 23 ... Suck chamber, 24 ... Injection hole, 30, 30A, 30B, 30C ... Needle, 32 ... Seat surface, 33 ... Conical part, 34, 35, 36 ... protruding part.

Claims (6)

A body (20) in which an injection hole (24) for injecting fuel to be burned in the internal combustion engine (10) is formed, and needles (30, 30A, 30B, 30C) housed in the body;
By seating the seat surface (32) of the needle on the seating surface (22) formed inside the body, the annular fuel passage (21) formed between the needle and the body is blocked. , Stop fuel injection from the nozzle hole,
In the fuel injection valve that opens the fuel passage by ejecting the seat from the seating surface and injects fuel from the injection hole,
A suck chamber (23) located between the fuel passage and the nozzle hole and collecting fuel distributed annularly in the fuel passage and leading to the nozzle hole is formed in the body. ,
A conical portion (33) extending in the axial direction of the needle while being tapered toward the sac chamber is formed in a portion of the needle downstream of the seat surface,
A fuel injection valve characterized in that a protruding portion (34, 35, 36) extending in the axial direction is formed at the tip of the conical portion in a shape with a reduced degree of taper.   The tip (30b) of the protruding portion is located on the bottom side of the sac chamber with respect to the center line (C) of the nozzle hole in a state where the needle is lifted up to the maximum. The fuel injection valve described in 1.   The distance (L1, L2) from the inlet of the nozzle hole to the needle in a state where the needle is seated is configured to be 35% or less of the diameter of the sac chamber. Item 3. The fuel injection valve according to Item 1 or 2.   The fuel injection valve according to any one of claims 1 to 3, wherein the projecting portion (35) has a conical shape extending from the tip of the conical portion while being tapered in the axial direction.   The fuel injection valve according to any one of claims 1 to 3, wherein the projecting portion (34) has a cylindrical shape extending from the tip of the conical portion without tapering in the axial direction.   The fuel injection according to any one of claims 1 to 3, wherein a flare portion (36a) extending in the axial direction while being tapered is formed at a tip of the protruding portion (36). valve.

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