JP4782804B2 - Fuel injection valve - Google Patents

Description

  The present invention relates to a fuel injection valve including a nozzle plate in which an injection hole for injecting fuel is formed.

  Conventionally, various fuel injection valves have been proposed. Patent Document 1 discloses a fuel injection valve as an example.

The fuel injection valve disclosed in Patent Document 1 includes a valve seat, a valve body that can be attached to and detached from the valve seat, a drive unit that drives the valve body, and a nozzle plate that injects fuel. . In this fuel injection valve, when the valve body is opened by being driven by the drive unit, the fuel that has passed between the valve body and the valve seat is injected from the injection hole of the nozzle plate. Thus, in a fuel injection valve equipped with a nozzle plate, fuel can be injected in a predetermined direction through the injection holes of the nozzle plate.
JP 2004-3518 A

  In a fuel injection valve, atomization of fuel to be injected is required. One means for atomizing the fuel is to promote mixing of the fuel and air.

  However, in the conventional fuel injection valve, the fuel that has passed between the valve body and the valve seat flows on the nozzle plate toward the center of the nozzle plate and collides with the nozzle plate, and then flows into the injection hole. Therefore, the fuel is not strongly pressed against the peripheral surface of the injection hole, and therefore a sufficient fuel film is not formed on the peripheral surface of the injection hole, so that a sufficient contact area between the fuel and the air in the injection hole is obtained. However, there is a problem that mixing of the fuel and air is not easily promoted and atomization of the fuel is not promoted.

  Accordingly, an object of the present invention is to promote atomization of fuel to be injected in a fuel injection valve.

The present invention provides a valve seat member in which a valve seat is formed, a valve body that can be attached to and detached from the valve seat, a drive unit that drives the valve body, and a downstream side of the valve seat, And a nozzle plate formed with an injection hole for injecting fuel that has passed between the valve body, and a plate that is stacked on the valve seat side of the nozzle plate and communicates with the injection hole An intermediate plate is formed between the nozzle plate and the intermediate plate, and the intermediate plate has a communication hole for guiding the fuel that has passed between the valve seat and the valve body to the inter-plate flow channel. The nozzle plate has a first bulging portion that bulges in a spherical shape toward the side opposite to the valve body side, and the jet is injected into the first bulging portion. holes are formed, the injection hole is axial line of the valve seat While located at a position farther than the communication hole against inclined with respect to the axial line of the valve seat so as to approach the axial line of the valve seat in accordance toward the downstream portion from the upstream portion of the injection hole a fuel injection valve, characterized in that it is configured so that the fuel flowing through the said plate between channels on the circumferential surface of the inclined injection holes are injected after a collision.

  According to the present invention, the injection hole is located at a position farther from the communication hole than the axial center line of the valve seat, and the axial center line of the valve seat extends from the upstream portion to the downstream portion of the injection hole. By inclining with respect to the axial center line of the valve seat so as to approach, when the fuel that has passed through the communication hole is guided to the flow path between the plates, reaches the injection hole, and is injected from the injection hole, the fuel is injected. It is possible to strongly press against the peripheral surface of the injection hole, thereby forming a fuel film in a wide range along the peripheral surface of the injection hole, so that the mixing of fuel and air can be promoted in the injection hole. Therefore, atomization of the fuel to be injected can be promoted.

[First Embodiment]
A first embodiment of the present invention will be described with reference to FIGS. This embodiment is an application example to a fuel injection valve used in an internal combustion engine mounted on a vehicle such as a four-wheeled vehicle or a two-wheeled vehicle. In the following description, for the sake of convenience, the end of the fuel injector that injects fuel is the tip of the fuel injector, and the end of the fuel injector that is supplied with fuel from the fuel pipe is the fuel injector. This will be referred to as the base end portion (the base end portion in the axial direction). In the description, the term “axial direction” refers to the axial direction of the fuel injection valve. 1 is a cross-sectional view showing a fuel injection valve according to the present embodiment together with an internal combustion engine, FIG. 2 is a cross-sectional view (cross-sectional view along the axial direction) showing the fuel injection valve according to the present embodiment, and FIG. It is sectional drawing (sectional drawing along an axial direction) which shows the front-end | tip part of the fuel injection valve concerning this embodiment.

  As shown in FIG. 1, the fuel injection valve 1 has a base end connected to the fuel pipe 103 via a connection pipe 101, and a tip end inserted into the insertion port 105 a of the internal combustion engine 105. Here, in the present embodiment, the insertion port 105 a is formed in the intake pipe 105 b of the internal combustion engine 105. The fuel injected from the fuel injection valve 1 is supplied into the cylinder 105e of the engine block 105d opened by opening the intake valve 105c.

  As shown in FIG. 2, the fuel injection valve 1 includes a substantially cylindrical metal cylinder 5 having a flow path 3 formed therein, and a flow path 3 provided inside the tip of the cylinder 5. The valve part 7 which opens and closes and the drive part 9 which drives this valve part 7 are provided.

  The cylindrical body 5 is formed as a relatively thin metal pipe having a step, for example, by subjecting a metal material such as magnetic stainless steel to press working such as deep drawing. The cylindrical body 5 is formed with a large diameter portion 5a on the base end side and a small diameter portion 5b having a smaller diameter than the large diameter portion 5a on the distal end side. The proximal end portion of the cylindrical body 5 is inserted into the connecting pipe 101, and the outer peripheral surface of the proximal end portion of the cylindrical body 5 closes the gap between the cylindrical body 5 and the connecting pipe 101, and is liquid-tight and airtight between them. An O-ring 11 that secures the above is extrapolated. The cylinder 5 is supplied with fuel that is pumped from a fuel pump (not shown) and flows through the fuel pipe 103 via the connection pipe 101, and the supplied fuel flows along the flow path 3. The cylinder 5 flows from the proximal end portion toward the distal end portion.

  A fuel filter 13 for filtering fuel is attached to the base end portion of the cylindrical body 5. The fuel filter 13 includes a cylindrical metal core 13a press-fitted into the large-diameter portion 5a of the cylinder 5, and a metal core 13a using a resin material softer than the cylinder 5, such as nylon or fluororesin. An integrally formed frame 13b and a mesh-like filter body 13c attached to the frame 13b and filtering fuel are provided.

  The valve portion 7 is disposed inside the distal end portion of the tubular body 5 and is made of a metal valve seat member 15 fixed to the tubular body 5, a metallic valve body 17 disposed inside the tubular body 5, It has.

  The valve seat member 15 is formed in a cylindrical shape, and a valve element hole 15a is formed in the axial direction. The valve element 17 is accommodated in the valve element hole 15a so as to be movable in the axial direction. An annular valve seat 15b is formed on the inner peripheral surface of the valve element hole 15a. Specifically, the inner diameter of the valve body hole 15a is formed to be small in a step shape from the base end to the tip, and one of the step surfaces is formed as a valve seat 15b. The valve seat member 15 is fixed to the cylindrical body 5 by all-around laser welding from the outside of the cylindrical body 5. This welding location is indicated by reference numeral 19 in the figure.

  An injection member 21 that closes the valve element hole 15 a is fixed to the tip of the valve seat member 15. As shown in FIG. 3, the injection member 21 is formed with an injection hole 21a as an orifice. The injection hole 21a opens into the intake pipe 105b of the internal combustion engine 105, and a valve seat 15b and a valve body are formed. The fuel that has passed between the two is injected. The injection member 21 is fixed to the valve seat member 15 by annular laser welding surrounding the injection hole 21a. This welding location is indicated by reference numeral 23 in FIG.

  As shown in FIGS. 2 and 3, the valve body 17 is formed in a spherical shape and can be attached to and detached from the valve seat 15 b. The valve body 17 is seated on the valve seat 15b of the valve seat member 15 by the driving force of the drive unit 9 (position shown in FIG. 3), and is opened from the valve seat 15b of the valve seat member 15 (see FIG. 3). 7 position) is reciprocated in the axial direction.

  The drive unit 9 is an electromagnetic actuator, and specifically drives the valve body 17 in the valve unit 7. As shown in FIG. 2, the drive unit 9 is disposed inside the cylinder 5 and fixed to the cylinder 5 (core cylinder) 25, and inside the cylinder 5 on the distal end side of the fixed core 25. A movable iron core (anchor) 27 that is arranged and movable in the axial direction, an electromagnetic coil 29 extrapolated to the cylindrical body 5 at a position outside the fixed iron core 25 and the movable iron core 27, and an inner peripheral side of the electromagnetic coil 29 A bobbin 31 arranged and a yoke 33 arranged on the outer peripheral side of the electromagnetic coil 29 are provided. The fixed iron core 25, the movable iron core 27, the electromagnetic coil, and the yoke 33 form a closed magnetic path.

  The fixed iron core 25 is formed in a cylindrical shape extending in the axial direction by a magnetic metal material. The fixed iron core 25 is press-fitted into the small-diameter portion 5b of the cylindrical body 5. The front end surface of the fixed iron core 25 has a relatively small gap δ in the base end surface of the movable iron core 27 when the fuel injection valve 1 is closed. Face each other. An adjuster cylinder 35 extending in the axial direction is fitted into the fixed iron core 25, and the fuel that has flowed into the fixed iron core 25 flows out of the fixed iron core 25 via the inside of the adjuster cylinder 35. It has become. That is, the fixed iron core 25 and the adjuster cylinder 35 form a part of the flow path 3.

  The movable iron core 27 is formed in a stepped cylindrical shape extending in the axial direction by a magnetic metal material, and has a large-diameter portion 27a facing the fixed iron core 25 and a large-diameter portion 27a having a smaller diameter than the large-diameter portion 27a. A small-diameter portion 27b that protrudes from the end portion of the fuel injection valve 1 toward the tip end side of the fuel injection valve 1. The valve body 17 is fixed to the front end portion of the movable iron core 27 by welding. With this structure, the valve body 17 moves integrally with the movable iron core 27. A concave portion 27c that opens toward the fixed iron core 25 is formed in the large diameter portion 27a of the movable iron core 27, and an opening portion 27d that communicates with the concave portion 27c is formed in the side surface in the small diameter portion 27b. A back pressure chamber 37 is formed between the outer peripheral surface of the small diameter portion 27 b of the movable iron core 27 and the inner peripheral surface of the cylindrical body 5. In the movable iron core 27 having such a structure, the fuel that has flowed into the recess 27c from the fixed iron core 25 flows out from the opening 27d into the back pressure chamber 37. That is, the movable iron core 27 forms a part of the flow path 3.

  A coil spring 39 as an urging member is interposed in a compressed state between the movable iron core 27 and the fixed iron core 25. The coil spring 39 is inserted into the recess 27c of the movable core 27, and one end (base end) thereof is in contact with the tip end surface of the adjuster cylinder 35, while the other end (tip end) is the recess 27c. It is in contact with the bottom surface. This coil spring 39 urges the movable iron core 27 and the valve body 17 in the valve closing direction of the valve body 17 and seats the valve body 17 on the valve seat 15b.

  The yoke 33 is formed in a stepped cylindrical shape, and has a large-diameter portion 33a that covers the outer periphery of the electromagnetic coil 29 and a smaller diameter than the large-diameter portion 33a, and the fuel injection valve 1 from the end of the large-diameter portion 33a. A small-diameter portion 33b that protrudes toward the distal end side. The yoke 33 has a small diameter portion 33b pressed into the small diameter portion 5b of the cylindrical body 5 and is fixed thereto.

  The bobbin 31 is formed in a cylindrical shape by a resin material and is extrapolated to the cylindrical body 5. The electromagnetic coil 29 is externally inserted into the cylindrical body with the electromagnetic coil 29 wound around the bobbin 31. The electromagnetic coil 29 is supplied with electric power from an external power source (not shown) via a pin 43 and a conductive path 45 provided on the connector 41.

  In the drive unit 9 having such a configuration, when the electromagnetic coil 29 is not energized, the state in which the valve element 17 is seated on the valve seat 15b is maintained by the biasing force of the coil spring 39 (valve closed state). In this case, a gap δ is formed between the fixed iron core 25 and the movable iron core 27 in the axial direction. On the other hand, when the electromagnetic coil 29 is energized, a closed magnetic path is formed by the electromagnetic coil 29, the fixed iron core 25, the movable iron core 27, and the yoke 33, whereby a magnetic force in the direction toward the fixed iron core 25 acts on the movable iron core 27. . Due to this magnetic force, the movable iron core 27 is attracted to the fixed iron core 25 against the urging force of the coil spring 39, and the valve seat member 15 that moves together with the movable iron core 27 separates from the valve seat 15b (valve open state). ).

  An O-ring 46 is externally inserted into the small-diameter portion 33 b of the yoke 33 of the drive unit 9, and this O-ring 46 is formed between the inner peripheral surface of the insertion port 105 a of the internal combustion engine 105 and the outer peripheral surface of the yoke 33. Close the gap to ensure liquid and air tightness between them.

  Further, the fuel injection valve 1 includes a cover 47 that covers an intermediate portion of the cylinder 5 and a protector 49 that covers the tip of the cylinder 5. The cover 47 is made of, for example, resin, and is formed by injection molding in a state where the yoke 33, the electromagnetic coil 29, and the like are assembled on the outer peripheral side of the cylindrical body 5. The cover 47 is integrally formed with the connector 41, and a conductive path 45 is formed in the cover 47. The protector 49 is formed in a cylindrical shape and is sheathed at the distal end portion of the cylindrical body 5 to protect the distal end portion of the cylindrical body 5.

  In the fuel injection valve 1 having such a configuration, when the electromagnetic coil 29 is energized and the valve body 17 is separated and opened, the fuel supplied into the cylinder 5 flows down the flow path 3. That is, the fuel is filtered by the fuel filter 13 and then flows into the back pressure chamber 37 via the fixed iron core 25 and the movable iron core 27, and the valve body 17 and the valve seat member 15 are opened from the back pressure chamber 37. It passes through the gap formed between the valve seat 15b and is injected from the injection hole 21a of the injection member 21 (see FIG. 7).

  Next, the injection member 21 will be described in detail with reference to FIGS. Here, FIG. 4 is a bottom view showing the nozzle plate according to the present embodiment, FIG. 5 shows an intermediate plate according to the present embodiment, (a) is a bottom view, and (b) is a view of (a). FIG. 6 is a bottom view showing the nozzle plate in the fuel injection state according to the present embodiment, and FIG. 7 is a front view of the fuel injection valve in the fuel injection state according to the present embodiment. FIG. 8 is a cross-sectional view (cross-sectional view along the axial direction) showing the fuel injection state injection member according to the present embodiment. 2, 3, and 7, a cross section taken along line BB in FIG. 4 is applied to the nozzle plate 53, and the nozzle plate 53 in FIG. A cross section along line C is applied. Moreover, the dashed-dotted line in FIG.6, FIG.7 and FIG.8 has shown schematically the fuel injected from the injection hole 21a.

  As shown in FIG. 3, the injection member 21 has a double plate structure in which an intermediate plate 51 and a nozzle plate 53 are laminated in the axial direction. The intermediate plate 51 and the nozzle plate 53 are disposed on the downstream side of the valve seat 15b. Specifically, the intermediate plate 51 is joined to the distal end surface (the lower end surface in FIG. 3) of the valve seat member 15, and the nozzle plate 53 is joined to the distal end surface (the lower end surface in FIG. 3) of the intermediate plate 51. Has been. These joints are made by welding the welded portion 23 described above. The intermediate plate 51 and the nozzle plate 53 are formed of a metal such as stainless steel.

  As shown in FIGS. 3 and 4, the nozzle plate 53 is formed in a disc shape, and the outer periphery is in contact with the inner periphery of the cylindrical body 5. The nozzle plate 53 includes an annular first flat plate portion 53a and a first bulging portion 53b that is located at the center of the nozzle plate 53 and that is continuous with the inner periphery of the second flat plate portion 51a. Is formed. The first bulging portion 53b is curved and bulged in a spherical shape toward the side opposite to the valve body 17 side. A plurality of injection holes 21a are formed in the first bulging portion 53b.

  As shown in FIGS. 3 and 5, the intermediate plate 51 is formed in a disc shape, and the outer periphery thereof is in contact with the inner periphery of the cylindrical body 5. The intermediate plate 51 is laminated on the valve seat 15b side of the nozzle plate 53 to form an inter-plate channel 55 between the nozzle plate 53, and this inter-plate channel 55 communicates with the injection hole 21a. ing. The intermediate plate 51 includes a substantially annular second flat plate portion 51a, and a second bulging portion 51b that is located at the center of the intermediate plate 51 and that is connected to the inner periphery of the second flat plate portion 51a. Is formed. The second bulging portion 51b is curved in a spherical shape toward the side opposite to the valve body 17 side, and bulges and faces the first bulging portion 53b. An inter-plate channel 55 is formed between the second bulging portion 51b and the first bulging portion 53b. A communication hole 51 c is formed in the second bulging portion 51 b, and the communication hole 51 c guides fuel that has passed between the valve seat 15 b and the valve body 17 to the inter-plate channel 55. In the present embodiment, only one communication hole 51c is formed in the central portion of the second bulging portion 51b along the axis a of the valve seat 15b, and the axis of the communication hole 51c is This coincides with the axis a of the valve seat 15b.

  The positional relationship between the injection hole 21a and the communication hole 51c will be described. As shown in FIG. 3, the injection hole 21a is positioned farther from the communication hole 51c with respect to the axial center line a of the valve seat 15b, and the valve is located in the direction from the upstream portion to the downstream portion of the injection hole 21a. It inclines with respect to the axial center line a of the said valve seat 15b so that the axial center line a of the seat 15b may be approached. That is, if the angle between the axis b of the injection hole 21a and the axis a of the valve seat 15b is θ, 0 ° <θ <90 °. Here, as described above, since the axial center line of the communication hole 51c coincides with the axial center line a of the valve seat 15b, the injection hole 21a is directed from the upstream portion to the downstream portion of the injection hole 21a. It inclines with respect to the axial center line of the communication hole 51c so that the axial center line of the communication hole 51c may be approached.

  Further, as shown in FIG. 4, four injection holes 21 a are provided in the present embodiment, and two injection holes 21 a are provided in line symmetry with respect to the axial center line of the nozzle plate 53. As shown in FIG. 6, the two injection holes 21a in the set are arranged so as to inject fuel in the same direction. Moreover, the injection hole 21a is arrange | positioned so that the fuel injected from different groups may not interfere.

  In the injection member 21 having such a configuration, as shown in FIGS. 7 and 8, the fuel that passes between the valve seat 15 b and the valve body 17 and flows out from the valve body hole 15 a of the valve seat member 15 is transferred to the intermediate plate. It passes through the communication hole 51c of the 51 and flows into the inter-plate flow path 55. Thereafter, the fuel that has flowed into the inter-plate flow path 55 is guided to the inter-plate flow path 55, reaches the injection holes 21a while spreading in a circular shape, and is injected from the injection holes.

  Here, in the present embodiment, the injection hole 21a is located at a position farther from the communication hole 51c with respect to the axial center line a of the valve seat 15b, and is directed from the upstream portion to the downstream portion of the injection hole 21a. It inclines with respect to the axial center line a of the said valve seat 15b so that the axial center line a of the valve seat 15b may be approached. Therefore, when the fuel is guided from the inter-plate flow path 55 to the inside of the injection hole 21a, as shown in FIG. 8, the fuel flow is bent at an acute angle and the fuel is strongly pressed against the peripheral surface 21b of the injection hole 21a. it can. As a result, a thin fuel film can be formed in a wide range along the peripheral surface of the injection hole 21a. Therefore, the contact area between the fuel and the air in the injection hole 21a is increased to mix the fuel and air. Therefore, atomization of the fuel to be injected can be promoted. In FIG. 8, for convenience of explanation, each part is exaggerated.

  Further, in the present embodiment, the nozzle plate 53 has the first bulging portion 53b, while the intermediate plate 51 has the second bulging portion 51b, and the first bulging portion 53b and the second bulging portion 53b. Since the inter-plate flow path 55 is formed between the bulging portion 51 b, the fuel can be guided along the surface of the nozzle plate 53 in the inter-plate flow path 55. As a result, compared to the case where the intermediate plate is a flat plate, when the fuel is guided from the inter-plate flow path 55 to the inside of the injection hole 21a, the flow of the fuel can be made an acute angle, and the fuel can be surrounded by the peripheral surface of the injection hole 21a. Can be pressed more strongly.

  Further, in this manner, the nozzle plate 53 has the first bulging portion 53b, while the intermediate plate 51 has the second bulging portion 51b, and the first bulging portion 53b and the second bulging portion. Since the inter-plate channel 55 is formed between the first and second plates 51b, the thickness of the inter-plate channel 55 (the distance between the first bulging portion 53b and the second bulging portion 51b) is substantially constant. Thus, the fuel flow rate in the inter-plate flow path 55 can be kept substantially constant. As a result, the fuel can be reliably and strongly pressed against the peripheral surface of the injection hole 21a.

  In the present embodiment, the nozzle plate 53 has the first bulging portion 53b, while the intermediate plate 51 has the second bulging portion 51b having a shape along the first bulging portion 53b. Therefore, compared with the case where both the nozzle plate and the intermediate plate are flat plates, for example, the strength of the nozzle plate 53 and the intermediate plate 51 is increased, and the reliability of the fuel injection valve 1 can be improved.

  In the present embodiment, a plurality of (two in the present embodiment) injection holes 21a are provided as a set, and the injection holes 21a are arranged so that fuel injected from different sets does not interfere with each other. Therefore, it can suppress that the fuel after atomizing by the injection hole 21a interferes and fuel particles increase.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 9 is a cross-sectional view (cross-sectional view along the axial direction) showing the tip of the fuel injection valve according to the present embodiment. In addition, the fuel injection valve 201 concerning this embodiment is provided with the component similar to the fuel injection valve 1 concerning 1st Embodiment. Therefore, the same components are denoted by common reference numerals, and redundant description is omitted.

  In the present embodiment, the injection member 221 of the fuel injection valve 201 is different from that of the first embodiment, and other configurations are the same as those of the first embodiment.

  The injection member 221 of this embodiment has a double plate structure in which an intermediate plate 251 and a nozzle plate 53 are stacked. The shape of the intermediate plate 251 is different from that of the first embodiment, and the nozzle plate 53 is the first plate. This is the same as the embodiment.

  The intermediate plate 251 is formed in a flat plate shape, and one communication hole 51 c is formed at the center of the intermediate plate 251. The axial center line of the communication hole 51c coincides with the axial center line a of the valve seat 15b. And the injection hole 21a of the nozzle plate 53 is located in the position far from the communication hole 51c with respect to the axial center line a of the valve seat 15b.

  In the fuel injection valve 201 of the present embodiment having the above-described configuration, as in the first embodiment, when the fuel is guided from the inter-plate flow path 255 to the inside of the injection hole 21a, the first bulge is generated in the nozzle plate 53. Since there is the portion 53b, the fuel flow can be bent at an acute angle and the fuel can be strongly pressed against the peripheral surface of the injection hole 21a. As a result, a thin fuel film can be formed in a wide range along the peripheral surface of the injection hole 21a. Therefore, the contact area between the fuel and the air in the injection hole 21a is increased to mix the fuel and air. Therefore, atomization of the fuel to be injected can be promoted.

  In the present embodiment, since the intermediate plate 251 is flat, the intermediate plate 251 can be manufactured relatively easily.

  The present invention is not limited to the above-described embodiments, and various other embodiments can be adopted without departing from the gist of the present invention. For example, both the nozzle plate and the intermediate plate of the injection member may be flat plates. In this case, a plate-to-plate channel may be formed by interposing a member between the nozzle plate and the intermediate plate to separate the nozzle plate and the intermediate plate.

  In the first embodiment, the thickness of the flow path between the plates is uniform. However, the thickness of the flow path is not uniform within the range in which the fuel is strongly pressed against the injection hole (for example, on the outer periphery of the intermediate plate). The thickness may gradually decrease toward the surface).

  Furthermore, a plurality of injection holes for the intermediate plate may be formed.

It is sectional drawing which shows the fuel injection valve concerning the 1st Embodiment of this invention with an internal combustion engine. It is sectional drawing (sectional drawing along an axial direction) which shows the fuel injection valve concerning the 1st Embodiment of this invention. It is sectional drawing (sectional drawing along an axial direction) which shows the front-end | tip part of the fuel injection valve concerning the 1st Embodiment of this invention. It is a bottom view which shows the nozzle plate concerning the 1st Embodiment of this invention. The intermediate | middle plate concerning the 1st Embodiment of this invention is shown, (a) is a bottom view, (b) is sectional drawing along the AA of (a). It is a bottom view which shows the nozzle plate of the fuel-injection state concerning the 1st Embodiment of this invention. It is sectional drawing (sectional drawing along an axial direction) which shows the front-end | tip part of the fuel injection valve of the fuel-injection state concerning the 1st Embodiment of this invention. It is sectional drawing (sectional drawing along an axial direction) which shows the injection member of the fuel-injection state concerning the 1st Embodiment of this invention. It is sectional drawing (sectional drawing along an axial direction) which shows the front-end | tip part of the fuel injection valve concerning the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,201 Fuel injection valve 9 Drive part 15 Valve seat member 15b Valve seat 17 Valve body 21a Injection hole 51,251 Intermediate | middle plate 51b 2nd bulging part 51c Communication hole 53 Nozzle plate 53b 1st bulging part 55,255 Flow path between plates a Shaft center line of valve seat

Claims (3)

A valve seat member formed with a valve seat;
A valve body that can be attached to and detached from the valve seat;
A drive unit for driving the valve body;
A nozzle plate that is disposed on the downstream side of the valve seat and has an injection hole for injecting fuel that has passed between the valve seat and the valve body;
In a fuel injection valve comprising:
An intermediate plate that is stacked on the valve seat side of the nozzle plate and forms a flow path between the plates communicating with the injection hole between the nozzle plate,
The intermediate plate is formed with a communication hole that guides the fuel that has passed between the valve seat and the valve body to the flow path between the plates,
The nozzle plate has a first bulging portion that bulges in a spherical shape toward the side opposite to the valve body side, and the injection hole is formed in the first bulging portion. ,
The injection hole is located farther than the communication hole with respect to the axial center line of the valve seat, and approaches the axial center line of the valve seat from the upstream portion to the downstream portion of the injection hole. The fuel injection is characterized in that it is inclined with respect to the axis of the valve seat and is injected after the fuel flowing through the flow path between the plates collides with the peripheral surface of the inclined injection hole. valve. The intermediate plate has a second bulging portion that bulges toward the opposite side of the valve body side and faces the first bulging portion and faces the second bulging portion, and communicates with the second bulging portion. A hole is formed,
The inter-plate flow path is formed between the first bulging portion and the second bulging portion, and the thickness of the inter-plate flow path is substantially constant. The fuel injection valve according to 1. The fuel injection valve according to claim 1, wherein the intermediate plate has a flat plate shape.

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