JP5258645B2 - Fuel injection valve - Google Patents

Description

  The present invention relates to a fuel injection valve that blows spray atomized by colliding fuel injected from a plurality of adjacent fuel injection holes to an intake port.

  Conventionally, various fuel injection valves have been proposed in which fuel sprayed from a plurality of adjacent fuel injection holes collides with each other and sprays atomized spray onto an intake port (see Patent Document 1).

  In the fuel injection valve 100 of the above publication, as shown in FIGS. 13 and 14, the tip portion 101a of the valve body 101 is formed in a conical shape, and two intake ports ( A plurality of sets of fuel injection holes 102 a, 102 b, 103 a, 103 b for ejecting fuel toward each other are provided. One adjacent fuel injection hole 102a, 102b and the other adjacent fuel injection hole 103a, 103b are formed symmetrically with respect to a center line L1 extending in the axial direction of FIG. Further, the center lines of one fuel injection hole 102 a and 102 b extend in a direction crossing each other below the valve body 101, and the center lines of the other fuel injection holes 103 a and 103 b are also mutually below the valve body 101. It extends in the crossing direction.

  In the above configuration, pressurized fuel flows into the valve body 101, fuel injected from one of the fuel injection holes 102a and 102b collides, and atomized spray 104 is sprayed to one intake port, and at the same time The fuel injected from the other fuel injection holes 103a and 103b collide with each other, and the atomized spray 105 is sprayed to the other intake port.

  As another conventional example, there is a fuel injection valve provided with a disk-shaped nozzle plate having a plurality of adjacent fuel injection holes at the tip of the valve body.

  In this conventional fuel injection valve 110, a disc-shaped nozzle plate 112 shown in FIG. 16 is provided at the tip of the valve body 111 shown in FIG. The disk-shaped nozzle plate 112 is provided with a plurality of sets of fuel injection holes 113a to 113f and 114a to 114f each having the same inner diameter. One fuel injection hole 113a to 113f and the other fuel injection hole 114a to 114f are arranged symmetrically with respect to the center line L1 in FIG. One set of adjacent fuel injection holes 113e and 113f in one of the fuel injection holes 113a to 113f is disposed near the center of the nozzle plate 112, and the other two sets of adjacent fuel injection holes 113a to 113d are respectively It is arranged on the outer diameter side slightly from the center. Similarly, one set of fuel injection holes 114e and 114f of the other fuel injection holes 114a to 114f is arranged near the center of the nozzle plate 112, and the other two sets of adjacent fuel injection holes 114a to 114d are Each is arranged slightly outside the center.

  Furthermore, the center lines of one set of adjacent fuel injection holes 113a and 113b extend in a direction intersecting with each other below the nozzle plate 112, and another set of adjacent fuel injection holes 113c and 113d and fuel injection holes 113e and 113f. The same applies to the fuel injection holes 114a and 114b, the fuel injection holes 114c and 114d, and the fuel injection holes 114e and 114f.

  In the above configuration, when pressurized fuel flows into the valve body 111, the fuel injected from one adjacent fuel injection hole 113a, 113b, fuel injection hole 113c, 113d, and fuel injection hole 113e, 113f, respectively. They collide and atomized sprays 115a, 115b, and 115c are sprayed on one intake port. At the same time, the fuels injected from the other adjacent fuel injection holes 113a and 113b, fuel injection holes 113c and 113d, and fuel injection holes 113e and 113f collide with each other, and the atomized sprays 116a, 116b, and 116c are injected into the other intake air. Sprayed on the port.

  As a result, as shown in FIG. 15A, when viewed from the front side of the fuel injection valve 110, one of the sprays 115a to 115c and the other spray 116a to 116c are separated into two hands, and these sprays 115a to 115c and A predetermined spray angle θ1 is formed between the sprays 116a to 116c. One spray 115a to 115c itself diffuses at a predetermined spray angle θ2, and similarly, the other spray 116a to 116c itself diffuses at a predetermined spray angle θ2. Further, as shown in FIG. 15B, the sprays 115a to 115c and the sprays 116a to 116c are diffused at a predetermined spray angle θ3 when viewed from the side of the fuel injection valve 110.

JP-A-9-42118

  However, in the conventional fuel injection valve 110 having the nozzle plate 112, the spray angles θ1 to θ3 change as indicated by solid lines A, B, and C in FIG. 17 with respect to the fuel pressure (that is, the pressure applied to the fuel). To do. Further, the non-collision type spray angles θ1 to θ3 in which the fuels injected from the nozzle plate 112 do not collide with each other change as indicated by broken lines D, E, and F in FIG. Among these, the spray angles θ1 and θ2 when viewed from the front side of the fuel injection valve 110 are indicated by solid lines A and B in FIG. 17 as compared to the non-collision type indicated by broken lines D and E in FIG. The collision type is quite large, that is, the spray angles θ1 and θ2 are likely to change with respect to changes in fuel pressure. However, the spray angle θ3 when viewed from the side surface of the fuel injection valve 110 is not much different for both the non-collision type shown by the broken line F in FIG. 17 and the collision type shown by the solid line C in FIG. However, the sensitivity of the spray angle θ3 to the change in fuel pressure is low. Therefore, since it is relatively difficult to change the spray angle θ3 only by controlling the fuel pressure in the fuel injection valve 110, the adjustment of the spray pattern is limited, improving the exhaust emission of the internal combustion engine, In addition, there is a problem that it is difficult to improve horsepower and fuel efficiency. The other fuel injection valves 100 have the same problem.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to allow fuel to be injected in the atomized state and to adjust the spray pattern by changing the spray angle by controlling the fuel pressure. It is an object of the present invention to provide a fuel injection valve that can be used.

In order to achieve the above object, the present invention comprises a nozzle plate disposed at the tip of a valve casing, and a plurality of fuel injection holes including through holes penetrating the nozzle plate. A fuel injection valve in which the fuel injection holes are set so that fuels supplied and injected from the adjacent fuel injection holes collide with each other, comprising a plurality of sets of the adjacent fuel injection holes, An inner diameter of at least one fuel injection hole is the same as the inner diameter of the hole set disposed in the vicinity of the center of the nozzle plate, and the inner diameter of at least one of the hole sets disposed in the radial direction of the hole set disposed in the vicinity of the center of the nozzle plate. Is set to be larger than the inner diameters of the other fuel injection holes .

  According to the present invention, when fuel is injected through the fuel injection hole of the nozzle plate at the tip of the valve casing, the fuels injected from the adjacent fuel injection holes collide with each other, and atomized spray is sprayed on the intake port. It is done. At this time, the flow resistance of at least one fuel injection hole is smaller than the flow resistance of the other fuel injection holes, and the magnitude of the spray energy of the fuel injected from these fuel injection holes becomes unbalanced. When the fuel pressure is low and when the fuel pressure is high, the particle vector balance of the spray formed by the collision of the fuels changes, and the spray direction becomes variable. Thus, the fuel can be injected in the atomized state, and the spray pattern can be adjusted by changing the spray angle by controlling the fuel pressure.

1 is a cross-sectional view of a fuel injection valve according to a first embodiment of the present invention. It is the bottom view which showed 1st Embodiment of this invention and looked at the nozzle plate from the downward direction when fuel pressure is low. It is the bottom view which showed 1st Embodiment of this invention and looked at the nozzle plate from the downward direction when fuel pressure is high. It is the figure which showed 1st Embodiment of this invention and looked at the spray pattern from the side surface side of the fuel injection valve. It is the figure which showed 1st Embodiment of this invention and looked at the spray pattern from the front side of the fuel injection valve. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a first embodiment of the present invention, and is a diagram for explaining an operating state of an internal combustion engine and a spray angle of a fuel injection valve, in which (a) is a diagram showing a spray angle of a fuel injection valve in a cold start state; The figure which shows the spray angle of the fuel injection valve in a warm-air driving | running state, (c) is a figure which shows the spray angle of the fuel injection valve in a WOT (wide, open, throttle) state. It is the bottom view which showed another aspect of 1st Embodiment and looked at the nozzle plate from the downward direction when fuel pressure is low. It is the bottom view which showed another aspect of 1st Embodiment and looked at the nozzle plate from the downward direction when fuel pressure is high. It is sectional drawing which shows 2nd Embodiment of this invention and expands and shows the principal part of a nozzle plate. It is sectional drawing which shows the 1st modification of the nozzle plate concerning this invention. It is sectional drawing which shows the 2nd modification of the nozzle plate concerning this invention. It is sectional drawing which shows the 3rd modification of the nozzle plate concerning this invention. It is the figure which showed the 1st prior art example and looked at the valve body from the side surface side of the fuel injection valve. It is the figure which showed the 1st prior art example and looked at sectional drawing which follows the XII-XII line | wire of FIG. A 2nd prior art example is shown, (a) is the figure which looked at the fuel injection valve from the front side, (b) is the figure which looked at the fuel injection valve from the side. It is the bottom view which showed the 2nd prior art example and looked at the nozzle plate from the downward direction. It is a characteristic figure which shows the transition of the injection angle with respect to fuel pressure which shows a 2nd prior art example.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(First embodiment)
1 to 6 show a first embodiment of the present invention.

  In FIG. 1, a fuel injection valve 1 includes a valve casing 3 in which a fuel passage 2 is formed, valve means 4 for opening and closing the fuel passage 2, and the valve means 4 between an open position and a closed position. The electromagnetic actuator 5 to be moved by the motor and the connector 6 for energizing the electromagnetic actuator 5 are mainly constituted.

  The valve casing 3 includes a metal pipe (magnetic cylinder) 10 and a resin mold portion 12 arranged so as to cover the entire outer periphery of the upper half of the metal pipe 10. The metal pipe 10 has a cylindrical shape, and the inside thereof is formed as the fuel passage 2. A conductive rod 13 is embedded in the resin mold portion 12 of the valve casing 3.

  A delivery pipe (not shown) is connected to the upper end of the metal pipe 10 so that fuel pumped by a fuel pump (not shown) is supplied from above the fuel passage 2 via the delivery pipe. A filter 14 is disposed at the upper end in the metal pipe 10, and impurities in the fuel are trapped by the filter 14.

  The valve means 4 is fixed to a lower end portion in the metal pipe 10 and is movable in a valve body member 15 having a valve body hole 15a penetrating in the vertical direction and the valve body hole 15a of the valve seat member 15. It is comprised from the substantially spherical valve body 16 arrange | positioned in this. The diameter of the valve body hole 15a is set to be small in a step shape from the upper side to the lower side, and one of the step surfaces is formed as a seat surface 15c. An orifice having an injection port 15b is provided below the valve body hole 15a. A disc-shaped nozzle plate 17 shown in FIGS. 2 and 3 is fixed to the lower end of the valve seat member 15, and the injection port 15 b is opened in the intake pipe 7 described later via the nozzle plate 17. .

  The valve body 16 has a valve closing position (position in FIG. 1) in close contact with the seating surface 15 c of the valve seat member 15 by a driving force of the electromagnetic actuator 5, and a valve opening position spaced apart from the seating surface 15 c of the valve seat member 15. Moved between. That is, in the valve closing position of the valve means 4, the seat surface 15 c of the valve seat member 15 is closed by the valve body 16 and fuel is not injected from the injection port 15 b, and in the valve opening position of the valve means 4, the valve seat member 15 The valve body hole 15a is opened, and fuel is injected from the injection port 15b through the nozzle plate 17.

  The nozzle plate 17 is provided with a plurality of sets of adjacent injection hole groups 18 and 19. One injection hole group 18 is constituted by fuel injection holes 18a to 18f, and the other injection hole group 19 is constituted by fuel injection holes 19a to 19f. The injection hole groups 18 and 19 are arranged symmetrically with respect to the center line L1 in FIGS. Further, the fuel injection holes 18a, 18b, 18e and the fuel injection holes 18c, 18d, 18f constituting one injection hole group 18 are arranged symmetrically with respect to the center line L2 perpendicular to the center line L1. . Similarly, the fuel injection holes 19a, 19b, 19e and the fuel injection holes 19c, 19d, 19f constituting the other injection hole group 19 are arranged symmetrically with respect to the center line L2 perpendicular to the center line L1. Yes. Moreover, the injection hole groups 18 and 19 are divided into three hole groups, each having two holes as one group.

  For one injection hole group 18, the first hole group is composed of fuel injection holes 18 e and 18 f, and is arranged at a target position in the vicinity of the center of the nozzle plate 17 with the center line L 2 interposed therebetween. The fuel injection holes 18e and 18f are set to have the same diameter, and the angles of the fuel injection holes 18e and 18f are set so that the center lines of the fuel injection holes 18e and 18f intersect at the injection destination. ing.

  The second hole set is composed of fuel injection holes 18a and 18b, and is arranged on the radially outer side of the nozzle plate 17 with respect to the first hole set. Further, the inner diameter of the outer fuel injection hole 18a in the direction along the center line L2 is set larger than the inner diameter of the inner fuel injection hole 18b, and each center line of the fuel injection holes 18a, 18b The angles of the fuel injection holes 18a and 18b are set so as to intersect.

  Similarly, the third hole set is composed of fuel injection holes 18c and 18d, and is arranged on the outer side in the radial direction of the nozzle plate 17 than the first hole set. Further, the inner diameter of the outer fuel injection hole 18d in the direction along the center line L2 is set larger than the inner diameter of the inner fuel injection hole 18c, and each center line of the fuel injection holes 18c, 18d The angles of the fuel injection holes 18a and 18b are set so as to intersect. Further, the fuel injection hole 18c is disposed at a target position with the fuel injection hole 18b and the fuel injection hole 18d sandwiching the center line L2, and the fuel injection hole 18a with the center line L2 interposed therebetween.

  Similarly to the one injection hole group 18, the other injection hole group 19 is divided into three hole sets each including two holes, and is arranged symmetrically with respect to the center line L2. Are arranged symmetrically with respect to the injection hole group 18 and the center line L1.

  The electromagnetic actuator 5 includes a fixed iron core (core cylinder) 20 fixed inside the metal pipe 10, a movable iron core 21 movably disposed inside the metal pipe 10, and outer peripheral positions of the fixed iron core 20 and the movable iron core 21. The electromagnetic coil 22 built in the valve casing 3, the bobbin 23 for winding the electromagnetic coil 22 disposed on the inner peripheral side of the electromagnetic coil 22, and the outer peripheral side of the electromagnetic coil 22 to form a magnetic path And a yoke 24 as a magnetic path forming part.

  The fixed iron core 20 is formed with a shaft hole 20a that opens to the upper and lower surfaces. The movable iron core 21 is formed with a shaft hole 21a as a communication hole opened on the upper surface, and a horizontal hole 21b as a communication hole communicating with the shaft hole 21a and opened on the side peripheral surface. The movable iron core 21 is disposed close to the lower side of the fixed iron core 20, and an upper-side large-diameter portion 21c and a lower-side small-diameter portion 21d are integrally formed. The large diameter portion 21 c has an outer diameter that is slightly smaller than the inner diameter of the metal pipe 10, and moves while sliding on the inner wall of the metal pipe 10. The small diameter portion 21 d has an outer diameter sufficiently smaller than the inner diameter of the metal pipe 10, and the outer peripheral side faces the fuel passage 2. A lateral hole 21b is opened on the side periphery of the small diameter portion 21d facing the fuel passage 2, and this opening is an outlet of the communication hole. The lower end of the small diameter portion 21d is fixed to the valve body 16 by welding or the like. Accordingly, the valve body 16 is changed to the body together with the movable iron core 21, the position where the movable iron core 21 abuts against the fixed iron core 20 is the valve opening position, and the position where the valve body 16 abuts against the seat surface 15c (the position where the valve body 16 contacts) is closed. Is in position.

  The movement resistor 27 has a flat ring shape, and its inner peripheral side is fixed to the outer periphery of the small-diameter portion 21d by welding, press fitting, or the like, and its outer peripheral side is a free end. The fixed position of the moving resistor 27 is set closer to the valve body 16 than the position of the lateral hole 21b of the small diameter portion 21d.

  A spring receiving member 25 is fixed inside the fixed iron core 20, and an upper end of a compression coil spring (biasing means) 26 is brought into contact with the spring receiving member 25. The lower end of the compression coil spring 26 is in contact with the movable iron core 21, and the valve body 16 is biased toward the valve closing position by the spring force of the compression coil spring 26. When the electromagnetic coil 22 is energized, the movable iron core 21 is displaced upward by electromagnetic force, the valve body 16 is shifted to the valve open position, and when the energization to the electromagnetic coil 22 is finished, the movable iron core 21 is compressed coil spring. The spring force of 26 returns to the valve closing position.

  Further, between the fuel passages 2 where the electromagnetic actuator 5 is disposed, a through hole 25 a of the spring receiving member 25, a shaft hole 20 a of the fixed iron core 20, a shaft hole 21 a of the movable iron core 21, and a horizontal hole 21 b of the movable iron core 21. It is communicated. Accordingly, the fuel in the fuel passage 2 above the electromagnetic actuator 5 flows in the order of the through hole 25a of the spring receiving member 25, the shaft hole 20a of the fixed iron core 20, the shaft hole 21a of the movable iron core 21, and the horizontal hole 21b of the movable iron core 21. By being guided, it flows into the fuel passage 2 below the electromagnetic actuator 5.

  The connector 6 includes a terminal portion 30 formed by one end side of the conductive rod 13 and a connector housing portion 31 integrally formed by the resin mold portion 12. The other end of the conductive rod 13 is connected to the electromagnetic coil 22 of the electromagnetic actuator 5 so that the electromagnetic coil 22 is energized from the connector 6.

  In addition, packings 32 and 33 are respectively fitted to the upper end side and the lower end side of the outer periphery of the valve casing 3. Packing 32 on the upper end side is for shielding connection of a delivery pipe (not shown), and packing 33 on the lower end side is for shielding connection of the fuel injection valve 1 to the intake pipe 7.

  Next, the operation of the fuel injection valve 1 will be described. The valve body 16 is located at the valve closing position, and the fuel passage 2 is filled with pressurized fuel. In this state, when the electromagnetic actuator 5 is energized, the valve body 16 changes from the valve closing position to the valve opening position, and the fuel in the fuel passage 2 passes through the fuel injection holes 18a to 18a of the nozzle plate 17 from the injection port 15b. It injects through 18f and 19a-19f. When energization of the electromagnetic actuator 5 is stopped, the valve body 16 is returned to the valve closing position and fuel injection is stopped. As described above, the energization / non-energization of the electromagnetic actuator 5 causes the fuel to be injected into the intake pipe at a predetermined timing and in a desired amount.

  As described above, when the fuel is injected through the fuel injection holes 18a to 18f of the nozzle plate 17, the fuel injection holes 18a and 18b, the fuel injection holes 18c and 18d, and the fuel injection hole 18e of the one injection hole group 18. , 18f collide with each other for each hole set, and atomized sprays 18g to 18i are sprayed on one intake port. At the same time, the fuel injected from the fuel injection holes 19a and 19b, the fuel injection holes 19c and 19d, and the fuel injection holes 19e and 19f of the other injection hole group 19 collide with each other, and atomized spray 19g. ˜19i is sprayed on the other intake port.

  As a result, as shown in FIG. 5, when viewed from the front side of the fuel injection valve 1, one of the sprays 18 g to 18 i and the other spray 19 g to 19 i are separated into two, and the sprays 18 g to 18 i and the spray 19 g to A predetermined spray angle θ1 is formed between 19i. One spray 18g-18i itself diffuses at a predetermined spray angle θ2, and similarly, the other spray 18g-18i itself diffuses at a predetermined spray angle θ2. Further, as shown in FIG. 4, when viewed from the side of the fuel injection valve 1, the sprays 18g to 18i and the sprays 19g to 19i diffuse at a predetermined spray angle θ3.

  At this time, among the pair of adjacent fuel injection holes 18a and 18b, the flow resistance of the fuel injection hole 18a having a large inner diameter is smaller than the flow resistance of the fuel injection hole 18b having a small inner diameter, and these fuel injection holes 18a. , 18b, and the amount of fuel injected from the fuel injection hole 18a is different depending on the injection direction of the fuel injection hole 18a. Therefore, when the fuel pressure is low and when the fuel pressure is high, the spray 18g formed when the fuels collide with each other. The spray direction depends on the flow rate of the fuel injection hole 18a, and the direction of the spray 18g is variable. The same applies to the other three sets of holes, the fuel injection holes 18c and 18d, the fuel injection holes 19a and 19b, and the fuel injection holes 19c and 19d.

  For example, by injecting fuel from the fuel injection valve 1 at a low fuel pressure, the directions of the sprays 18g and 18h on both sides are slightly separated from the intermediate spray 18i and the flow of the sprays 18g to 18i as shown in FIG. Since the speed is low and the air resistance is relatively small, the sprays 18g to 18i themselves diffuse, so the spray angle θ3 increases. Similarly, the spray angle θ3 of the other sprays 19g to 19i also increases.

  On the other hand, by injecting fuel from the fuel injection valve 1 at a high fuel pressure, the directions of the sprays 18g and 18h on both sides approach the intermediate spray 18i and the flow of the sprays 18g to 18i as shown in FIG. Since the speed increases and the air resistance increases, the degree to which the sprays 18g to 18i themselves diffuse each decreases, so the spray angle θ3 of the sprays 18g to 18i and the sprays 19g to 19i decreases.

  In the first embodiment, the fuel can be injected in the atomized state, and the fuel pressure is increased / decreased according to the operation state of the internal combustion engine, so that the fuel injection valve 1 is viewed from the side surface side. The spray pattern can be adjusted by changing the spray angle θ3 of the sprays 18g to 18i and the spray angle θ3 of the sprays 19g to 19i.

  For example, at the time of cold start, by injecting fuel at a low fuel pressure, the spray angle θ3 of the sprays 18g to 18i and the sprays 19g to 19i is increased as shown in FIG. The surface area of 19g to 19i can be increased, and the vaporization of the wall flow in the intake pipe 7 can be promoted.

  Next, during the warm-up operation, the fuel is injected at a medium fuel pressure, so that the spray angles θ3 of the sprays 18g to 18i and the sprays 19g to 19i are narrowed and become high as shown in FIG. 6 (b). By spraying sprays 18g to 18i and sprays 19g to 19i intensively toward the intake valve 8, heat is received from the intake valve 8 and the vaporization of the wall flow in the intake pipe 7 is promoted.

  Next, during WTO operation, by injecting fuel at a high fuel pressure, as shown in FIG. 6C, the spray angles θ3 of the sprays 18g to 18i and the sprays 19g to 19i are further narrowed. The air can be cooled by supplying fuel into the intake pipe 7 without adhering to the wall around the intake pipe 7.

  Therefore, the pattern of the sprays 18g to 18i and the sprays 19g to 19i can be adjusted by increasing / decreasing the fuel pressure according to the operating state of the internal combustion engine, so that the exhaust emission of the internal combustion engine can be improved, and the horsepower and fuel efficiency can be improved. Can be improved.

  In the present embodiment, the hole set is constituted by two fuel injection holes, but the hole set is constituted by three or more fuel injection holes, and the flow resistance of one of the three fuel injection holes is reduced. Even if it is set to a small value or a different flow path resistance is set for each of the three fuel injection holes, the same effect can be obtained.

  As another aspect of the first embodiment, there is a nozzle plate 17 'shown in FIGS. The nozzle plate 17 ′ is provided with a plurality of sets of adjacent injection hole groups 18 ′ and 19 ′ as in the first embodiment.

  For one injection hole group 18 ', the first hole set and the fuel injection holes 18e' and 18f 'are configured in the same manner as the first hole set in the first embodiment.

  The second hole set, the fuel injection holes 18a 'and 18b', has an inner diameter of the outer fuel injection hole 18a 'in the direction along the center line L2 with respect to the second hole set of the first embodiment. The difference is that it is set smaller than the inner diameter of the fuel injection hole 18b '. Similarly, the third hole set, the fuel injection holes 18c 'and 18d', has an inner diameter of the fuel injection hole 18d 'on the outer side in the direction along the center line L2 with respect to the third hole set of the first embodiment. The difference is that it is set smaller than the inner diameter of the inner fuel injection hole 18c '.

  The other injection hole group 19 'is divided into three sets of holes, one set of two holes, as in the case of the one injection hole group 19'. The first hole set, the fuel injection hole 19e ' , 19f 'are configured in the same manner as the first hole set of the first embodiment, the second hole set, fuel injection holes 19a', 19b ', the third hole set, fuel injection hole 19c. ′, 19d ′ is a fuel in which the inner diameter of the outer fuel injection hole 19a ′ in the direction along the center line L2 is the inner side of the second hole set and the third hole set in the first embodiment. It differs from the first embodiment in that it is set smaller than the inner diameter of the injection hole 19b '.

  When the fuel pressure is low, contrary to the first embodiment, the inner diameter of the outer fuel injection hole 19a 'in the direction along the center line L2 is set smaller than the inner diameter of the inner fuel injection hole 19b'. When the fuel pressure is high, the spray angle θ3 can be reduced.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

  In FIG. 9, the second embodiment is different from the first embodiment only in the configuration of the nozzle plate 40. In the nozzle plate 40 of the second embodiment, one adjacent fuel injection hole 41 is gradually reduced in diameter from the upstream side toward the downstream side, and the inner diameter of the other fuel injection hole 42 is set to be constant. At the same time, the inner diameter is set to be equal to the downstream inner diameter of one fuel injection hole 41. Since the configuration other than the nozzle plate 40 is the same as that of the first embodiment, the same components as those of the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted.

  Also in the second embodiment, the flow resistance of one fuel injection hole 41 is smaller than the flow resistance of the other fuel injection hole 42, so the injection amount of fuel injected from these fuel injection holes 41, 42 is small. Differently, the injection flow depends on the injection direction of the fuel injection hole 41. Therefore, when the fuel pressure is low and high, the spray direction of the spray formed when the fuel collides with each other is the flow rate of the fuel injection hole 41. The spray direction is variable. Therefore, as in the first embodiment, the fuel can be injected in the atomized state, and the fuel pressure is increased / decreased according to the operating state of the internal combustion engine, as viewed from the side of the fuel injection valve. The spray pattern can be adjusted by changing the spray angle θ3 of the spray in the state.

  The present invention can be embodied in another embodiment as follows. In the following other embodiments, the same operations and effects as those of the above embodiment can be obtained.

  In the first embodiment, a pair of adjacent fuel injection holes 18a and 18b have different inner diameters, and another set of fuel injection holes 18c and 18d, fuel injection holes 19a and 19b, and fuel injection holes 19c and 19d are also included. In the second embodiment, one adjacent fuel injection hole 41 is reduced in diameter from the upstream side toward the downstream side, and the inner diameter of the other fuel injection hole 42 is set to be constant. In addition, the configuration is set to be equal to the inner diameter of the downstream side of the one fuel injection hole 41.

(First modification)
On the other hand, as another configuration for realizing different flow path resistances, as shown in FIG. 10, the configuration in which the upstream end side of one adjacent fuel injection hole 51 is expanded in a mortar shape may be used. This flow path resistance can be made smaller than the flow path resistance of the other fuel injection hole 52. And since the magnitude of the spray energy of the injected fuel becomes unbalanced, the fuel can be injected in the atomized state, and the fuel pressure can be increased or decreased depending on the operating state of the internal combustion engine. The spray pattern can be adjusted by changing the spray angle θ3 of the spray viewed from the side of the injection valve.

(Second modification)
Further, even if the mortar shape of the fuel injection hole 51 in the first modification is such that the upstream end of one adjacent fuel injection hole 61 is chamfered as shown in FIG. Is less than the flow resistance of the other fuel injection hole 62, and a sufficient effect is obtained.

(Third Modification)
Furthermore, as another configuration for realizing different flow path resistances, as shown in FIG. 12, one fuel injection hole 72 adjacent to the thin plate portion 71 of the nozzle plate 70 is provided, and the other fuel injection is made to the thick plate portion 73. A hole 74 may be provided. In this case, the hole length of one fuel injection hole 72 is shorter than the hole length of the other fuel injection hole 74, and the flow resistance of one fuel injection hole 72 is changed to the flow resistance of the other fuel injection hole 74. It can be made smaller. As a result, the magnitude of the spray energy of the fuel injected from the fuel injection holes 72 and 74 becomes unbalanced, so that the fuel is formed by colliding with each other when the fuel pressure is low and high. The spray particle vector balance changes and the spray direction is variable.

DESCRIPTION OF SYMBOLS 1 Fuel injection valve 2 Fuel passage 3 Valve casing 5 Electromagnetic actuator 16 Valve body 17 Nozzle plate 18a-18f Fuel injection hole 18g-18i Spray 19a-19f Fuel injection hole 19g-19i Spray 40 Nozzle plate 41, 42 Fuel injection hole 51, 52 Fuel injection holes 61, 62 Fuel injection holes 70 Nozzle plate 71 Thin plate portion 72 Fuel injection holes 73 Thick plate portion 74 Fuel injection holes

Claims (1)

A nozzle plate disposed at the tip of the valve casing;
A plurality of fuel injection holes comprising through holes penetrating the nozzle plate;
A fuel injection valve in which the fuel injection hole is set so that fuels supplied into the valve casing and injected from the adjacent fuel injection holes collide with each other;
A plurality of sets of adjacent fuel injection holes are provided,
The inner diameter of the hole set arranged near the center of the nozzle plate is the same,
Among the hole sets arranged radially outside the hole set arranged near the center of the nozzle plate, the inner diameter of at least one fuel injection hole is set larger than the inner diameters of the other fuel injection holes. Fuel injection valve.

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