JP2007211735A - Fuel injection valve and method for manufacturing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel injection valve capable of increasing liquid-tightness without deteriorating durability and reliability, and a method for manufacturing the same. <P>SOLUTION: In an injector 1 provided with a nozzle body 7 pressed in a tip of a body 3 and supplied with high pressure fuel to an inside thereof, a valve seat part 10 provided on a tip part of the nozzle body 7 and provided with an injection hole part 10a and a valve seat surface 10b, a valve element 9 provided in such a manner that the same can be seated on the valve seat surface 10b, and an orifice plate 11 having an orifice 11a formed with corresponding to the injection hole part 10b, and injecting high pressure fuel from the orifice 11a by separating a valve part 9b of the valve element 9 from the valve seat surface 10b, the valve seat part is formed out of amorphous alloy and the valve seat surface 10b is pressure-formed, the nozzle body is formed out of martensitic stainless steel and the valve seat part 10 is joined to the nozzle body 7 by plastic flow joining. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel injection valve that injects high-pressure fuel by opening a valve body with respect to a valve seat, and a method for manufacturing the same.

  The fuel injection valve is used in a fuel supply device for supplying fuel to an engine. A fuel supply device provided in an engine includes a fuel tank that stores fuel, a fuel pump that pumps fuel from the fuel tank, and a fuel line that sends high-pressure fuel discharged from the fuel pump to a delivery pipe disposed near the engine. I have. In order to inject and supply the high pressure fuel sent to the delivery pipe to each cylinder, a fuel injection valve (injector) is provided in the delivery pipe. The injector is required to improve liquid tightness when the valve is closed (a state in which the valve element is in contact with the valve seat). This is because if the liquid tightness is poor, a small amount of fuel is supplied even after the engine is stopped, so that a large amount of HC (hydrocarbon) is discharged when the engine is restarted.

  An example of such an injector is disclosed in Japanese Patent Application Laid-Open No. 2004-239245. The injector disclosed here includes an orifice at the tip, a nozzle body to which high-pressure fuel is supplied, a valve seat provided in the nozzle body corresponding to the orifice, and an interior of the nozzle body. The valve body is provided so as to be seated on the valve seat, and high-pressure fuel is injected from the orifice when the valve body is opened relative to the valve seat. In this injector, the nozzle body (including the valve seat) and the valve body are made of metal glass (amorphous alloy). Thereby, in this injector, the improvement of liquid-tightness, durability, and reliability is aimed at.

JP 2004-239245 A

  However, in the above-described injector, since the nozzle body (valve seat) and the valve body are made of an amorphous alloy (amorphous), the sliding portion of the valve body causes a contact portion between the nozzle body and the valve body. There was a problem of being easy to wear. If the contact portion between the nozzle body and the valve body is worn, the nozzle body cannot firmly guide the movement of the valve body in the axial direction, the valve body does not operate normally, and the fuel There is a risk of lowering the injection accuracy. Thus, the above-described injector has a problem that durability and reliability may be reduced.

  Accordingly, the present invention has been made to solve the above-described problems, and provides a fuel injection valve capable of improving liquid tightness without reducing durability and reliability, and a method for manufacturing the same. Is an issue.

  In order to solve the above problems, a fuel injection valve according to the present invention includes a nozzle body that is press-fitted into the front end of the body and is supplied with high-pressure fuel therein, and is provided at the front end of the nozzle body. A valve seat portion having a hole portion and a valve seat surface, a valve body provided to be seated on the valve seat surface of the valve seat portion inside the body, and an orifice corresponding to the injection hole portion are formed. A fuel injection valve that injects high-pressure fuel from the orifice by separating the valve body from the valve seat surface, the valve seat portion is formed of an amorphous alloy, and the nozzle body It is formed of hard stainless steel.

In this fuel injection valve, when the valve element is separated (opened) from the valve seat surface, the high-pressure fuel supplied to the inside of the nozzle body is injected from the orifice through the injection hole portion.
And in this fuel injection valve, the valve seat part is formed with the amorphous alloy. Here, the amorphous alloy is a metal including a stable amorphous material such as oxide glass, and easily deforms (plastic flow) at a high temperature. The deformation characteristics of such an amorphous alloy are excellent in mechanical strength because there is no specific sliding surface present in the crystal alloy because the atomic arrangement is random. The material properties of the amorphous alloy are relatively high tensile strength and relatively low Young's modulus. As for the corrosion resistance of the amorphous alloy, since the structure and composition are homogeneous, the passive film formed on the surface is uniform and there is no grain boundary, so the corrosion resistance is excellent. And by performing an oxidation process, a zirconia film | membrane is formed in the surface and abrasion resistance improves. The high density of the amorphous alloy is high because the shape of the mold is transferred (reproduced) to the casting with high accuracy according to the dimensions of the mold. In this way, the shape of the mold is transferred (reproduced) to the casting with high accuracy because the amorphous alloy has a supercooled liquid region, so there is no need to consider solidification shrinkage. This is because the surface of the mold is reproduced with high accuracy.

  Therefore, by forming the valve seat portion from an amorphous alloy, the dimensional accuracy of the valve seat is increased, and post-processing is not required. Further, since the Young's modulus of the amorphous alloy is relatively low, the adhesion between the valve seat and the valve body is improved, so that the liquid tightness is improved. Further, the mechanical strength of the valve seat portion is improved, and the corrosion resistance is also improved by the passive film having a uniform surface. Furthermore, it is advantageous in terms of cost compared to the case where the entire nozzle body is formed of an amorphous alloy.

In this fuel injection valve, the nozzle body is made of hard stainless steel. Since hard stainless steel has high wear resistance, it is possible to prevent wear at the contact portion between the nozzle body and the valve body, which is generated when the valve body slides. Here, the nozzle body guides the movement of the valve body in the axial direction. And since the contact part of a nozzle body and a valve body does not wear, the exact operation | movement of a valve body can be ensured, and the injection precision of a fuel is not reduced.
Thus, according to the fuel injection valve of the present invention, liquid tightness can be improved without reducing durability and reliability.

  Further, since the valve seat portion is formed of an amorphous alloy and the nozzle body is formed of hard stainless steel in this way, an orifice plate having an orifice formed corresponding to the nozzle hole portion is attached to the nozzle body. It can be easily welded and fixed to the tip. That is, the orifice plate can be welded and fixed to the nozzle body better than in the case where the entire nozzle body is made of an amorphous alloy as in the conventional fuel injection valve. Further, since the orifice plate can be satisfactorily fixed to the nozzle body by welding, the liquid tightness of the portion can also be improved.

  In the fuel injection valve according to the present invention, it is preferable that a valve seat surface with which the valve body abuts is pressed to form the valve seat portion.

  As described above, in the amorphous alloy, the shape of the mold is transferred (reproduced) to the casting with high accuracy according to the dimensions of the mold, but the viscous flow in the supercooled liquid region of the amorphous alloy By using the pressure molding, the shape accuracy and surface roughness of the valve seat surface can be further improved. Therefore, when the valve seat surface is pressed, the liquid tightness between the valve seat and the valve body can be further enhanced.

  In the fuel injection valve according to the present invention, it is preferable that the valve seat portion is plastically flow-coupled to the nozzle body.

  Since the amorphous alloy has poor weldability, liquid-tightness is deteriorated when the valve seat is welded to the nozzle body. For this reason, the valve seat portion can be liquid-tightly coupled to the nozzle body by plastic flow coupling of the valve seat portion to the nozzle body.

  In the fuel injection valve according to the present invention, it is preferable that at least one circumferential groove is formed in the nozzle body on a coupling surface with the valve seat portion.

By forming such a circumferential groove in the nozzle body, the amorphous alloy forming the valve seat portion is plastically flowed to fill the circumferential groove, and the nozzle body and the valve seat portion are liquid-tightly connected. can do.
Here, if the volume of the plastic seat in the valve seat portion and the volume of the circumferential groove are the same, theoretically, it is sufficient to provide one circumferential groove. However, in practice, the plastic flow amount of the amorphous alloy in the valve seat varies depending on product errors, manufacturing conditions, and the like. Preferably, two or more circumferential grooves are formed in the nozzle body. Is good.

  In the fuel injection valve according to the present invention, it is desirable that a circumferential punch mark is formed on the outer peripheral portion of the distal end surface of the valve seat portion.

  By forming such punch marks, the outer peripheral portion of the tip surface of the valve seat portion is pressed to cause the amorphous alloy to plastically flow. That is, the amorphous alloy can be plastically flowed by pressing the portion closest to the circumferential groove on the distal end surface of the valve seat portion. As a result, the circumferential groove can be reliably filled with the amorphous alloy, and the plastic flow coupling of the valve seat portion to the nozzle body can be performed while ensuring high liquid tightness.

  Furthermore, in the fuel injection valve according to the present invention, it is desirable that a part of the outer periphery of the nozzle body is formed of an amorphous alloy in a circumferential shape.

  Since a part of the outer periphery of the nozzle body (that is, the press-fitted portion with respect to the body) is formed of an amorphous alloy in a circumferential shape, liquid-tightness can be improved between the body and the nozzle body. It is.

  Here, the fuel injection valve manufacturing method described above includes a nozzle body that is press-fitted into the tip of the body and is supplied with high-pressure fuel therein, and is provided at the tip of the nozzle body. A valve seat provided inside the body so as to be seated on a valve seat surface of the valve seat, and an orifice plate in which an orifice is formed corresponding to the injection hole. In the method of manufacturing a fuel injection valve in which high pressure fuel is injected from the orifice by separating the valve body from the valve seat surface, the valve seat portion is molded from an amorphous alloy by a die casting method, A step of disposing a valve seat molded by a mold casting method in the nozzle body from a direction opposite to the position of the valve body, and a valve seat surface of the valve seat molded by the mold casting method. The step of press-molding with a pressing member Characterized in that it comprises a step of plastic flow coupling the valve seat portion which is molded by a die casting method to the nozzle body by plastic flow coupling fixture, a.

  With such a manufacturing method, it is possible to manufacture a fuel injection valve capable of improving liquid tightness without deteriorating the durability and reliability described above.

In the method for manufacturing a fuel injection valve according to the present invention, it is desirable to simultaneously perform the pressure molding of the valve seat portion molded by the die casting method and the plastic flow coupling to the nozzle body.
Specifically, the pressing member may be pressed against the valve seat surface and the plastic flow coupling jig (punch) may be pressed against the opposite surface of the valve seat surface. Thereby, the pressure molding of the valve seat surface in the valve seat portion and the plastic flow coupling of the valve seat portion to the nozzle body can be performed simultaneously. Therefore, even if only the valve seat portion is formed of an amorphous alloy and joined to the nozzle body, the production efficiency is not lowered.

  According to the fuel injection valve of the present invention, as described above, liquid tightness can be improved without reducing durability and reliability. In addition, according to the method for manufacturing a fuel injection valve according to the present invention, a fuel injection valve capable of improving liquid tightness without reducing production efficiency and without reducing durability and reliability is manufactured. Can do.

  Hereinafter, a most preferred embodiment in which the fuel injection valve of the present invention is embodied will be described in detail with reference to the drawings. In the present embodiment, an injector used in a fuel supply device for supplying fuel to an automobile engine is exemplified as the fuel injection valve of the present invention.

  Therefore, an injector according to an embodiment will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing a schematic configuration of an injector according to an embodiment. FIG. 2 is an enlarged cross-sectional view of the vicinity of the nozzle portion in the injector shown in FIG. FIG. 3 is a cross-sectional view showing a schematic configuration of the tip portion of the nozzle body in a state where the valve seat portion is not attached. FIG. 4 is a cross-sectional view illustrating a schematic configuration of a tip portion of the nozzle body in a state where the valve seat portion is mounted. FIG. 5 is a cross-sectional view of the orifice plate. FIG. 6 is a plan view of the orifice plate.

  As shown in FIG. 1, the injector 1 is provided with a body 3 provided inside the housing 2, an adjustment pipe 4 provided inside the body 3, and substantially at the center between the housing 2 and the body 3. A solenoid 5, a nozzle body 7 press-fitted inside the tip of the body 3, a valve body 9, and an orifice plate 11 provided at the tip of the nozzle body 7 are provided. In this embodiment, the nozzle body 7 and the orifice plate 11 assembled to each other constitute an injection nozzle.

The base end portion of the body 3 is a pipe connector 12 connected to a delivery pipe (not shown). An O-ring 13 is attached around the pipe connector 12. A strainer 14 for removing foreign substances is provided inside the pipe connector 12.
A wiring connector 15 is integrally formed in the housing 2. The wiring connector 15 is provided with a terminal 16. The solenoid 5 includes a coil 17 and a bobbin 18. The coil 17 is connected to the terminal 16.

  On the other hand, the nozzle body 7 press-fitted inside the tip of the body 3 has a cup shape. The nozzle body 7 is made of martensitic stainless steel. A circumferential amorphous alloy portion 7 b is formed on a part of the outer periphery of the nozzle body 7. In the present embodiment, “Zr—Al—Ni—Cu alloy”) is used as the material of the amorphous alloy portion 7b. By providing such an amorphous alloy portion 7 b, liquid tightness between the body 3 and the nozzle body 7 can be enhanced when the nozzle body 7 is press-fitted into the tip of the body 3.

  Then, as shown in FIG. 2, a valve seat portion 10 made of an amorphous alloy is coupled to the inside of the tip of the nozzle body 7. The nozzle body 7 and the valve seat portion 10 are connected by plastic flow bonding (metal flow). Therefore, as shown in FIG. 3, two metal flow circumferential grooves 7a are formed in the joint portion of the nozzle body 7. The nozzle body 7 and the valve seat portion 10 can be coupled by plastically flowing a part of the valve seat portion 10 in these circumferential grooves 7a. In addition, the method to couple | bond both by metal flow is mentioned later.

As shown in FIG. 4, the nozzle seat 7 coupled to the inside of the nozzle body 7 is formed with an injection hole 10a and a valve seat surface 10b. In this embodiment, “Zr—Al—Ni—Cu alloy”, which is relatively easy to make an alloy, is used as the material of the valve seat portion 10. Such a valve seat portion 10 is molded by precision casting, and then the valve seat surface 10b is press-molded so that the valve seat surface 10b has the same cross-sectional shape as the valve body 9 (a shape that follows the valve body 9). It is molded into. Further, a circumferential punch mark 10 c is formed on the outer peripheral portion of the tip of the valve seat portion 10.
In addition, the press molding method of the valve seat surface 10b will be described later together with the metal flow method.

  An orifice plate 11 is fixed to the tip of the nozzle body 10 by welding. As shown in FIG. 5, the orifice plate 11 has a flat cup shape, and a plurality of orifices 11a as fuel outlets are formed at the center thereof. The plurality of orifices 11a are formed with a predetermined angle with respect to the central axis O. The inclination of the orifice 11a gives an inclination in the fuel injection direction. In addition, the plurality of orifices 11a are distributed as shown in FIG. Thereby, the atomization and atomization of the injected fuel are achieved.

  In the present embodiment, the nozzle body 7 is made of martensitic stainless steel, and the orifice plate 11 is made of austenitic stainless steel. For this reason, welding fixation of the nozzle body 7 and the orifice plate 11 can be performed favorably, and the liquid-tightness between the nozzle body 7 and the orifice plate 11 can be improved.

Returning to FIG. 1, the valve body 9 includes a shaft portion 9a, a spherical valve portion 9b provided at the distal end of the shaft portion 9a, and an armature portion 9c provided at the proximal end of the shaft portion 9a. The shaft portion 9a and the armature portion 9c of the valve body 9 are integrally formed of a magnetic material such as “Permalloy, electromagnetic stainless steel”. The valve portion 9b is made of martensitic stainless steel, and is integrally formed with the shaft portion 9a by welding or the like. The valve portion 9 b of the valve body 9 is arranged in alignment with the valve seat surface 10 b of the valve seat portion 10. Further, the armature portion 9 c of the valve body 9 is disposed adjacent to the solenoid 5. Since the armature portion 9c is formed of a magnetic material, the armature portion 9c is attracted by the magnetic force of the solenoid 5. In addition, the part located between the solenoid 5 and the armature part 9c is carburized and made non-magnetic.
A spring 21 is provided between the adjustment pipe 4 and the armature portion 9c. The spring 21 urges the valve body 9 in a direction in which the valve portion 9 b of the valve body 9 is brought into contact with the valve seat surface 10 b of the valve seat portion 10. For this reason, when the solenoid 5 is not energized, the valve portion 9 b of the valve body 9 is in contact with the valve seat surface 10 b of the valve seat portion 10.

  Next, a method for manufacturing the injector 1 will be described with reference to FIGS. FIG. 7 is an explanatory view showing a state before the valve seat is mounted on the nozzle body. FIG. 8 is an explanatory view for explaining a method of pressing the valve seat surface and a metal flow coupling of the valve seat portion to the nozzle body. Here, the manufacturing process similar to the conventional one is omitted, and only the characteristic process (manufacturing process of the nozzle portion) in the present invention is described.

First, as shown in FIG. 7, the valve seat portion 10 formed by precision casting moves from the direction opposite to the arrangement position of the valve body portion 9 b (upward in FIG. 7) to the inside of the tip of the nozzle body 7. Installed. At this time, the valve seat 10 remains in the state shown in FIG. That is, the amorphous alloy of the valve seat portion 10 is not plastically flowed.
When the valve seat portion 10 is mounted inside the tip end of the nozzle body 7, the pressing member 30 is pressed against the valve seat surface 10 b of the valve body portion 10 as shown in FIG. 8. The contact surface of the pressing member 30 with respect to the valve seat surface 10b has a highly accurate conical shape.

  Thereafter, in a state where the pressing member 30 is pressed against the valve seat surface 10b of the valve body portion 10, the metal flow punch 31 is pressed against the valve seat portion 10 from the opposite side of the valve seat surface 10b. The diameter of the tip of the metal flow punch 31 is substantially the same as the diameter of the valve seat 10. An annular convex portion 31 a is formed on the outer periphery of the front end surface of the metal flow punch 31. Then, the valve seat 10 is pressed from both sides by the pressing member 30 and the metal flow punch 31 in a state where the annular convex portion 31 a is in contact with the outer peripheral portion of the valve seat 10.

As a result, the valve seat surface 10b is press-molded, and a part of the valve seat portion 10 is plastically flowed into the circumferential groove 7a of the nozzle body 7 so that the valve seat portion 10 is coupled to the nozzle body 7 by metal flow. As a result, the valve seat 10 is deformed as shown in FIG. 4, a circumferential punch mark 10 c is formed on the outer periphery of the tip of the valve seat 10, and the valve seat 10 is located inside the tip of the nozzle body 7. Combined.
Thus, by performing the metal flow so that the circumferential punch mark 10c is formed on the outer peripheral portion of the tip of the valve seat portion 10, the portion closest to the circumferential groove 7a on the distal end surface of the valve seat portion 10 Can be made to plastically flow a part of the valve seat portion 10. Thereby, a part of valve seat part 10 can be reliably filled in the circumferential groove 7a. Therefore, the valve seat 10 can be coupled to the inside of the tip of the nozzle body 7 while ensuring high liquid tightness.

  Here, two circumferential grooves 7 a are formed in the joint portion of the nozzle body 7. For this reason, even if the plastic flow amount of the amorphous alloy in the valve seat portion 10 varies due to product errors, manufacturing conditions, etc., the variation is absorbed by one circumferential groove 7a (one far from the punch mark 10c). At the same time, the whole of the other circumferential groove 7a (the one closer to the punch mark 10c) can be filled with an amorphous alloy. As a result, the valve seat 10 can be coupled to the inside of the tip of the nozzle body 7 with high liquid-tightness regardless of product errors and manufacturing conditions.

  In addition, the portion of the valve seat 10 that contacts the valve seat surface 10b is press-molded by the pressing member 30 formed in a highly accurate conical shape. Due to the viscous flow of the crystalline alloy, the shape accuracy and surface roughness of the valve seat surface 10b can be further improved. Accordingly, the liquid tightness between the valve seat surface 10b and the valve portion 9b can be further enhanced.

  Next, the operation of the injector 1 having the above configuration will be described. When the solenoid 5 is energized in the injector 1, an attractive force due to the magnetic force of the solenoid 5 acts on the armature portion 9 c of the valve body 9. Due to this suction force, the valve element 9 moves against the spring 21, and the valve portion 9b opens away from the valve seat surface 10b. As a result, the fuel supplied from the pipe connector 12 to the inside of the body 3 is injected through the injection hole portion 10 a of the valve seat portion 10 and each orifice 11 a of the orifice plate 11.

  On the other hand, when the energization to the solenoid 5 is stopped, the attractive force of the solenoid 5 with respect to the armature portion 9c disappears. If it does so, the valve body 9 will be moved by the urging | biasing force of the spring 21, and the valve part 9b will closely_contact | adhere to the valve seat surface 10b, and will close. As a result, fuel injection from the injection hole 10a and each orifice 11a is stopped.

  Since the nozzle body 7 is made of martensitic stainless steel having excellent wear resistance, the contact (sliding) portion between the nozzle body 7 and the valve portion 9b generated by the movement of the valve body 9 is used. Wear can be prevented. Thereby, since the internal peripheral surface of the nozzle body 7 can always guide the valve part 9b, the exact operation | movement of the valve body 9 can be ensured. As a result, the reliability of the injector 1 can be improved without deteriorating the fuel injection accuracy in the injector 1.

As described above, according to the injector 1 according to the present embodiment, since the valve seat portion 10 is formed of an amorphous alloy and the valve seat surface 10b is press-molded, the shape accuracy of the valve seat surface 10b. And surface roughness can be improved. Accordingly, the liquid tightness between the valve seat surface 10b and the valve portion 9b can be enhanced. Moreover, according to the injector 1 which concerns on this Embodiment, since the nozzle body 7 is formed with martensitic stainless steel, the contact with the nozzle body 7 and valve part 9b which generate | occur | produces when the valve body 9 moves. Wear at the (sliding) portion can be prevented. Therefore, the reliability and durability of the injector 1 can be improved without reducing the fuel injection accuracy in the injector 1.
Thus, according to the injector 1 which concerns on this Embodiment, liquid-tightness can be improved, without reducing durability and reliability.

  It should be noted that the above-described embodiment is merely an example and does not limit the present invention in any way, and various improvements and modifications can be made without departing from the scope of the invention. For example, the injector 1 in the above-described embodiment has the valve body 9 including the spherical valve portion 9b, but an injector having a valve body portion having a shape other than this (for example, a needle-shaped valve body) The present invention can also be applied to a device having a part.

It is sectional drawing which shows schematic structure of the injector which concerns on embodiment. It is an expanded sectional view near the nozzle part in the injector shown in FIG. It is sectional drawing which shows schematic structure of the front-end | tip part of a nozzle body in the state in which a valve seat part is not mounted | worn. It is sectional drawing which shows schematic structure of the front-end | tip part of the nozzle body in the state in which the valve seat part was mounted | worn. It is sectional drawing of an orifice plate. It is a top view of an orifice plate. It is explanatory drawing which shows the state before mounting | wearing with a valve seat part in a nozzle body. It is explanatory drawing for demonstrating the pressure-molding of a valve seat surface, and the method of metal-flow joining a valve seat part to a nozzle body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Injector 2 Housing 3 Body 5 Solenoid 7 Nozzle body 7a Circumferential groove 7b Amorphous alloy part 9 Valve body 10 Valve seat part 10a Injection hole part 10b Valve seat surface 10c Punch mark 11 Orifice plate 11a Orifice 12 Piping connector 21 Spring 30 Press member 31 Metal flow punch 31a Annular convex part

Claims (9)

A nozzle body that is press-fitted into the tip of the body and is supplied with high-pressure fuel; a valve seat that is provided at the tip of the nozzle body and includes a nozzle hole part and a valve seat surface; A valve body provided so as to be seated on a valve seat surface of the valve seat portion; and an orifice plate in which an orifice is formed corresponding to the nozzle hole portion, and the valve body is separated from the valve seat surface. In the fuel injection valve for injecting high-pressure fuel from the orifice by
The fuel injection valve, wherein the valve seat portion is made of an amorphous alloy, and the nozzle body is made of hard stainless steel. The fuel injection valve according to claim 1, wherein
The fuel injection valve according to claim 1, wherein a valve seat surface with which the valve element abuts is pressed. The fuel injection valve according to claim 1 or 2,
The fuel injection valve, wherein the valve seat portion is plastically flow-coupled to the nozzle body. The fuel injection valve according to claim 3, wherein
The fuel injection valve according to claim 1, wherein at least one circumferential groove is formed in a coupling surface with the valve seat portion in the nozzle body. In the fuel injection valve according to claim 3 or claim 4,
A fuel injection valve characterized in that a circumferential punch mark is formed on an outer peripheral portion of a tip surface of the valve seat portion. The fuel injection valve according to any one of claims 1 to 5,
The fuel injection valve, wherein the orifice plate is fixed to a tip portion of the nozzle body by welding. The fuel injection valve according to any one of claims 1 to 6,
A part of the outer periphery of the nozzle body is formed of an amorphous alloy in a circumferential shape. A nozzle body that is press-fitted into the tip of the body and is supplied with high-pressure fuel; a valve seat that is provided at the tip of the nozzle body and includes a nozzle hole part and a valve seat surface; A valve body provided so as to be seated on a valve seat surface of the valve seat portion; and an orifice plate in which an orifice is formed corresponding to the nozzle hole portion, and the valve body is separated from the valve seat surface. In the method of manufacturing a fuel injection valve for injecting high-pressure fuel from the orifice by
Molding the valve seat from an amorphous alloy by a mold casting method;
A step of disposing a valve seat molded by a die casting method in the nozzle body from a direction opposite to the disposition position of the valve body;
A step of pressing and molding the valve seat surface of the valve seat portion molded by the die casting method with a pressing member;
A step of plastic flow coupling the valve seat molded by the die casting method to the nozzle body by a plastic flow coupling jig;
A fuel injection valve manufacturing method comprising: In the manufacturing method of the fuel injection valve according to claim 8,
A method of manufacturing a fuel injection valve, comprising simultaneously performing pressure molding of a valve seat surface in a valve seat portion molded by a die casting method and plastic flow coupling to the nozzle body.

Images