JP2002276505A - Fuel injection valve and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently manufacture an injection valve by molding a resin cover and a resin ring together on the outer peripheral side of a magnetic cylinder body. SOLUTION: A valve element storing part 2A, a core member inserting part 2B, a thin part 2C, and a fuel passage part 2D of the magnetic cylinder body 2 are integrally formed of metal pipes or the like. In manufacturing the injection valve, a valve seat member 5, a magnetic coil 12, a magnetic cover 13, a connecting core 15, and the like are firstly mounted to the magnetic cylinder body 2, the resin cover 16 and a protector 19 are injection molded and together mounted on the outer peripheral side of the magnetic cylinder body 2, and then a valve element 8, a core cylinder 9, an energizing spring 10, a spring bearing 11, a seal ring 18, and the like are mounted to the magnetic cylinder body 2. Thus, the injection molding of the resin cover 16 and the protector 19, the mounting to the magnetic cylinder body 2, and the like can be performed in one process, and thus the injection valve can be efficiently manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel injection valve suitably used for injecting fuel into, for example, an automobile engine or the like, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In general, for example, a fuel injection valve used in an automobile engine or the like has a valve casing formed as a magnetic cylinder made of a cylindrical magnetic metal material or the like. It is inserted as possible. During operation of the injection valve, when a valve element is opened by a magnetic field generated from an electromagnetic coil, fuel supplied to the magnetic cylinder is injected toward an intake pipe of an engine or the like (for example, see Japanese Patent Application Laid-Open 2001-27169, etc.).

In this type of fuel injection valve according to the prior art, a valve seat member is provided at a distal end side of a magnetic cylinder, a core member is fixed to a base end side of the magnetic cylinder, and these valve seat members and A valve body is arranged between the core member and the core member. The valve element is magnetically attracted by the core member when a magnetic field is generated from the electromagnetic coil, and is opened by separating from the valve seat member. Further, a resin cover is fixedly provided on the outer periphery of the base end side of the magnetic cylinder by, for example, injection molding or the like, and a connector for supplying power to the electromagnetic coil is provided on the resin cover.

[0004] The magnetic cylinder is fitted and attached to a boss or the like provided in an intake pipe of an engine, for example. For this reason, a seal member that seals between the boss portion of the intake pipe and the magnetic cylinder, and a protector that protects the seal member and the tip side of the magnetic cylinder are attached to the tip side of the magnetic cylinder. ing. In this case, the protector is formed in a cylindrical shape using, for example, a resin material or the like, and is fitted to the tip end side of the magnetic cylindrical body. Further, the protector holds the seal member at the tip end of the magnetic cylinder so as not to come off, thereby preventing the seal member from falling off from the tip end of the magnetic cylinder.

At the time of manufacturing the fuel injection valve configured as described above, first, a valve seat member, a valve body, a core member, an electromagnetic coil, and the like are attached to the magnetic cylinder, and a resin cover is provided by injection molding. Then, for example, a pressurizing jig or the like is inserted from the front end side of the magnetic cylinder to push the valve seat member and the valve body toward the back side, and a gap between the valve body and the core member (the valve body) (The lift amount) is adjusted to a predetermined size. Further, the protector is formed by resin molding in advance, and the protector and the seal member are attached to the distal end side of the magnetic cylinder to complete the injection valve.

[0006]

By the way, in the above-mentioned prior art, a protector formed in advance of resin is mounted on the tip end side of the magnetic cylinder. In this case, when manufacturing the injection valve, a jig or the like is inserted from the tip side of the magnetic cylinder to adjust the lift amount of the valve body, so that the lift amount is adjusted so that the protector does not hinder the adjustment work. The protector is attached after the adjustment.

However, when manufacturing the injection valve, the protector must be resin-molded in a process different from that of an assembly line or the like, and it is necessary to manually attach the protector to each magnetic cylinder. For this reason, in the related art, there is a problem that it takes time and effort to perform the resin molding and assembling, and it is difficult to efficiently manufacture the injection valve.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to reduce the number of parts when assembling an injection valve, improve workability at the time of assembling, and improve the injection valve. It is an object of the present invention to provide a fuel injection valve which can be manufactured efficiently and a method for manufacturing the same.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a magnetic cylinder formed of a magnetic material in a cylindrical shape, and an injection port provided at an axial front end of the magnetic cylinder. A valve seat member having an enclosed valve seat, a valve body displaceably provided in the magnetic cylinder and detachably seated on a valve seat of the valve seat member, and an axially intermediate portion of the magnetic cylinder. The present invention is applied to a fuel injection valve including an electromagnetic actuator that opens the valve body and a resin cover that covers an outer periphery on a base end side of the magnetic cylinder.

A feature of the structure adopted in the first aspect of the invention is that a resin ring is provided on the outer periphery of the tip end of the magnetic cylinder using the same resin material as the resin cover.

[0011] With this configuration, the resin cover and the resin ring can be formed together on the outer peripheral side of the magnetic cylinder by, for example, injection molding of a resin material. Can be performed in a single step. And
The resin ring can, for example, hold the sealing member or the like at the distal end side of the magnetic cylinder in a retaining state or protect the magnetic cylinder or the sealing member.

According to the second aspect of the present invention, the resin ring is folded back so as to cover the front end surface of the magnetic cylinder between the outer peripheral side and the inner peripheral side of the magnetic cylinder. Section is provided.

[0013] Thus, the tip end side of the magnetic cylinder can be covered by the folded portion of the resin ring, and this portion can be protected from collision with foreign matter.

According to the third aspect of the present invention, a connecting portion for connecting the resin cover and the resin ring is provided between the resin cover and the resin ring, and the resin cover, the resin ring, and the connecting portion are integrally formed by resin molding. And

Thus, the resin cover and the resin ring can be integrally connected by the connecting portion, and the strength of the resin ring fixed to the outer peripheral side of the magnetic cylinder can be further increased.

According to the fourth aspect of the present invention, the magnetic cylinder is formed on the outer peripheral side of the magnetic cylindrical body by a magnetic material and covers the electromagnetic actuator attached to the outer peripheral side of the magnetic cylindrical body from the radial outside. A cover is provided, and the magnetic cover is mounted by fitting a distal end portion located on the distal end side with respect to the electromagnetic actuator to an outer peripheral side of the magnetic cylinder, and the resin ring is at least a distal end portion of the magnetic cylinder and the magnetic cover. To cover the boundary position between

Thus, the magnetic cylinder and the magnetic cover are
The electromagnetic actuator can be accommodated between these by arranging them in a heavy cylindrical shape, and a magnetic path can be formed inside and outside the electromagnetic actuator. In addition, since the resin ring can cover at least the boundary position between the magnetic cylinder and the distal end portion of the magnetic cover, even if a step, unevenness, or the like is generated in this portion by a weld bead or the like, the magnetic ring is formed by the resin ring. The space between the body and the magnetic cover can be sealed against foreign substances such as dust and moisture.

According to the fifth aspect of the present invention, a seal for sealing between the magnetic cylinder and the mounting portion when the magnetic cylinder is mounted on an external mounting portion is provided on the outer circumference of the distal end side of the magnetic cylindrical body. A member is provided, and the resin ring is configured to hold the seal member at the tip end side of the magnetic cylinder in a retaining state.

Thus, the resin ring can hold the seal member attached to the outer periphery on the distal end side of the magnetic cylinder in a retaining state, and can prevent the seal member from falling off the magnetic cylinder.

According to the present invention, a connector having terminal pins connected to the electromagnetic actuator is formed integrally with the resin cover by resin molding.

Thus, the connector for supplying power to the electromagnetic actuator, the resin cover, and the resin ring can be integrally molded with the resin.

On the other hand, according to the manufacturing method of the present invention, the electromagnetic actuator and the valve seat member are assembled on the outer peripheral side of the magnetic cylinder, and the magnetic cylinder, the electromagnetic actuator and the valve seat member are assembled. A resin cover that covers the outer periphery on the base end side of the magnetic cylinder by injecting a resin material into the resin mold, and a resin ring positioned on the outer periphery on the distal end side of the magnetic cylinder. Is molded into a resin, and then a valve body is assembled in the magnetic cylinder.

Thus, when the injection valve is manufactured, the electromagnetic actuator and the valve seat member can be assembled to the magnetic cylinder, and these assembled bodies can be arranged in the resin mold to inject the resin material. As a result, on the outer peripheral side of the magnetic cylinder, the resin cover and the resin ring can be molded and fixed almost simultaneously with the resin, and thereafter, the injection valve can be manufactured by assembling the valve body in the magnetic cylinder. it can.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a fuel injection valve according to an embodiment of the present invention and a method for manufacturing the same will be described in detail with reference to the accompanying drawings.

FIGS. 1 to 7 show a first embodiment of the present invention. In this embodiment, a fuel injection valve used for an automobile engine will be described as an example.

Reference numeral 1 denotes a valve casing which forms an outer shell of the fuel injection valve. The valve casing 1 includes a magnetic cylinder 2, a magnetic cover 13, and a resin cover 16 which will be described later.

Reference numeral 2 denotes a magnetic cylinder constituting a main body of the valve casing 1. The magnetic cylinder 2 is made of a metal pipe or the like formed of a magnetic metal material such as an electromagnetic stainless steel, for example. As shown in the figure, it is integrally formed in a stepped cylindrical shape.

The magnetic cylinder 2 is located at the distal end thereof and accommodates a valve body 8 to be described later displaceably.
A, provided adjacent to the base end side of the valve body housing portion 2A,
A core member insertion portion 2B into which a core tube 9 to be described later is inserted, an annular thin portion 2C provided over the entire circumference between the valve body housing portion 2A and the core member insertion portion 2B, Member insertion part 2B
A fuel passage portion 2D provided on the base end side of the core member insertion portion 2B as a cylindrical body having a diameter larger than that of the core member insertion portion 2B, and these are arranged substantially coaxially.

Further, the valve body accommodating portion 2A and the core member inserting portion 2
B is formed as cylindrical bodies having substantially the same diameter as each other as shown in FIG. 2, and the thin portion 2C is formed to be thinner than these portions by using means such as press working or grinding. The thin portion 2C is disposed so as to surround the gap S between the suction portion 8C of the valve body 8 and the core tube 9 from the radial outside, and at this position, the valve body housing portion 2A and the core member insertion portion 2B Is increased in the axial direction. On the other hand, a fuel passage 3 extending in the axial direction and a fuel filter 4 for filtering fuel supplied from the outside to the fuel passage 3 are provided in the fuel passage portion 2D.

Reference numeral 5 denotes a cylindrical valve seat member provided by being inserted into the inner periphery of the distal end side of the valve housing 2A of the magnetic cylindrical body 2. The valve seat member 5 has, as shown in FIG. An injection port 5A for injecting the fuel in the fuel passage 3 to the outside, and an annular valve seat 5B which is formed in a conical shape surrounding the injection port 5A and on which a valve portion 8B of a valve body 8 described later detaches and seats. Is provided.

The valve seat member 5 is inserted into the inner periphery of the distal end side of the valve housing 2A of the magnetic cylinder 2, and the outer periphery of the valve seat 5 is entirely formed around the valve housing 2A by an annular welded portion 6. Have been welded. In addition, a nozzle plate 7 having a plurality of nozzle holes 7A is fixed to the tip end surface of the valve seat member 5 at a position covering the injection ports 5A.

Numeral 8 designates a valve body which is displaceably accommodated in a valve body accommodating portion 2A of the magnetic cylinder 2, and which extends axially in the valve body accommodating portion 2A as shown in FIG. 8A cylindrical valve shaft
And a spherical valve body 8B fixed to the distal end side of the valve shaft 8A and detachably seated on the valve seat 5B of the valve seat member 5, and formed on the base end side of the valve shaft 8A using, for example, a magnetic metal material. And a cylindrical suction portion 8C slidably inserted into the valve body housing portion 2A.

When the valve 8 is closed, the valve portion 8 is closed.
B is caused by the spring force of the urging spring 10 described later.
At this time, the base end surface of the suction portion 8C and the core cylinder 9 are sandwiched by an axial gap S having a gap dimension previously adjusted as the lift amount of the valve body 8. Face to face.

When power is supplied to an electromagnetic coil 12, which will be described later, when a magnetic field H is formed by the electromagnetic coil 12,
The suction portion 8C of the valve element 8 is magnetically attracted by the core tube 9. As a result, the valve element 8 is displaced in the axial direction by the dimension of the gap S against the spring force of the biasing spring 10, and opens in the direction of arrow A in FIG.

Reference numeral 9 denotes a core tube formed of, for example, a magnetic metal material and the like. The core tube 9 is inserted into the core member insertion portion 2B of the magnetic cylinder 2 in the axial direction with the base end surface of the suction portion 8C. Gap S
And is fitted to the core member insertion portion 2B at a position facing the suction portion 8C of the valve body 8.

Reference numeral 10 denotes an urging spring provided in the magnetic cylinder 2, and the urging spring 10 is connected to a cylindrical spring receiver 11 fixed to the inner peripheral side of the core cylinder 9 by press-fitting or the like. The valve body 8 is disposed in a compressed state between the valve body 8 and constantly biases the valve body 8 in the valve closing direction.

Reference numeral 12 denotes an electromagnetic coil serving as an electromagnetic actuator which is provided on the outer peripheral side of the core member insertion portion 2B of the magnetic cylinder 2, and the electromagnetic coil 12 is provided between the magnetic cylinder 2 and the magnetic cover 13. It is housed in between. The electromagnetic coil 12 generates a magnetic field H by being supplied with power using a connector 17 described later, and opens the valve body 8 against the spring force of the biasing spring 10.

Numeral 13 denotes a magnetic cover formed in a stepped cylindrical shape with a magnetic metal material or the like.
As shown in FIGS. 2 and 3, a small-diameter cylindrical portion 13A fitted to the outer peripheral side of the valve body accommodating portion 2A of the magnetic cylindrical body 2 at a position on the distal end side with respect to the electromagnetic coil 12, and the small-diameter cylindrical portion 13A An annular flange portion 13B which is bent in an L-shaped cross section from the base end side and protrudes radially outward; and a small-diameter cylindrical portion 13A on the outer peripheral side of the flange portion 13B.
And a large-diameter cylindrical portion 13C that is integrally formed as a larger-diameter cylindrical body and covers the electromagnetic coil 12 from the outside in the radial direction.

The small-diameter cylindrical portion 13A has its distal end 13A1 welded to the outer peripheral surface of the valve housing 2A at the position of the annular welded portion 14. Further, a connection core 15 formed in a substantially C-shape from, for example, a magnetic metal material is inserted into the outer peripheral side of the core member insertion portion 2 </ b> B of the magnetic cylinder 2. A magnetic path is formed on the outer peripheral side of the electromagnetic coil 12 in cooperation with the magnetic cover 13 while magnetically connecting between the large-diameter cylindrical portion 13C and the core member insertion portion 2B of the magnetic cylindrical body 2. I have.

Thus, when the electromagnetic coil 12 is operated, the valve housing 2A of the magnetic cylinder 2 and the core member insertion portion 2
B, a magnetic field H is formed along a closed magnetic path constituted by the suction portion 8C of the valve body 8, the core cylinder 9, the magnetic cover 13, and the connecting core 15. At this time, the valve housing 2 of the magnetic cylinder 2
A and the core member insertion portion 2B are almost magnetically shielded by the thin portion 2C, so that the magnetic field H passes through the gap S between the suction portion 8C of the valve body 8 and the core cylinder 9. Become
The valve element 8 is adsorbed on the core tube 9.

Reference numeral 16 denotes a resin cover that covers the outer periphery of the magnetic cylinder 2 and the base end side of the magnetic cover 13 from the radial outside, and the resin cover 16 is formed by injection molding a resin material, for example, as shown in FIG. It is fixed to the cylinder 2 and the magnetic cover 13. Also, the resin cover 16 has the electromagnetic coil 1
2 having terminal pin 17A for supplying power to connector 2
7 are integrally molded with resin.

Reference numeral 18 denotes a seal member such as an O-ring mounted on the outer periphery of the distal end side of the magnetic cylinder 2. The seal member 18 is attached to a mounting portion (not shown) such as a boss provided in an intake pipe of the engine. When the distal end side of the magnetic cylinder 2 is fitted to the magnetic cylinder 2, the space between the mounting portion and the magnetic cylinder 2 is sealed. And the sealing member 18 is used for the magnetic cover 1.
3 is disposed on the outer peripheral side of the small-diameter cylindrical portion 13A,
It is held in a retaining state between B and a protector 19 described later.

Reference numeral 19 denotes a protector as a resin ring fixedly provided on the outer periphery of the distal end side of the magnetic cylinder 2. The protector 19 is injection molded together with the resin cover 16 in an injection molding step shown in FIG. As a result, it is formed in an annular shape using the same resin material as the resin cover 16. As shown in FIG. 4, the protector 19 has an annular fixing portion 19A fixed on the inner peripheral side between the magnetic cylinder 2 and the magnetic cover 13, and an outer circumferential side of the fixing portion 19A. And a flange-shaped convex portion 19B that is positioned and protrudes radially outward from the inner diameter of the seal member 18.

Here, a part of the fixing portion 19A is fixed over the entire circumference at a boundary position (near the welded portion 14) between the distal end portion 13A1 of the magnetic cover 13 and the outer peripheral surface of the magnetic cylinder 2. It covers this boundary position. Thereby, even if there is a step, unevenness, or the like at the boundary between the magnetic cylinder 2 and the magnetic cover 13 due to a bead or the like of the welded portion 14, the protector 19 seals the gap over the entire circumference,
This prevents dust, moisture and the like in the intake air from entering the steps, irregularities, and the like between the magnetic cylinder 2 and the magnetic cover 13.

The protector 19 has a flange-like projection 19B.
The seal member 18 is held at the distal end side of the magnetic cylinder 2 in a retaining state by using the seal member 18 and is sealed against foreign substances such as dust flowing together with intake air in the intake pipe of the engine.
And the tip of the magnetic cylindrical body 2 and the like are protected.

The fuel injection valve according to the present embodiment has the above-described configuration, and its operation will now be described.

First, when the injection valve operates, the connector 17
When power is supplied to the electromagnetic coil 12 from, a magnetic field H is formed as shown in FIG. At this time, the valve housing 2 of the magnetic cylinder 2
A and the core member insertion portion 2B are almost magnetically shielded by the thin portion 2C.
It passes between C and the core tube 9.

As a result, the valve element 8 is magnetically attracted by the core cylinder 9 and is displaced in the direction of arrow A against the urging spring 10, so that the valve portion 8B is connected to the valve seat of the valve seat member 5. Open the valve away from 5B. Thereby, the fuel supplied into the fuel passage 3 is injected from the injection port 5A toward the intake pipe of the engine or the like.

Next, a method of manufacturing the fuel injection valve according to the present embodiment will be described with reference to FIGS.

First, in the first component assembling step shown in FIG. 5, the electromagnetic coil 12, the magnetic cover 13 and the connecting core 15 are inserted and fitted on the outer peripheral side of the magnetic cylinder 2, so that the distal end portion 13A1 of the magnetic cover 13 is The outer peripheral surface of the magnetic cylinder 2 is welded by the welded portion 14. Further, the valve seat member 5 is welded to the inner periphery of the distal end side of the magnetic cylinder 2, and an assembled body 21 composed of the magnetic cylinder 2, the valve seat member 5, the electromagnetic coil 12, the magnetic cover 13, the connection core 15, and the like. To form

Next, in the injection molding step shown in FIG. 6, the assembled body 21 is placed in a resin mold 22 and a resin material is injected into the resin mold 22. Here, the resin mold 22 has a concave portion 22A corresponding to the shape of the resin cover 16 and the protector 19,
22B are formed in advance. Thereby, the magnetic cylinder 2
The resin cover 16 and the protector 19 can be almost simultaneously injection-molded and fixed to the outer peripheral side of.

Next, in the second component assembling step shown in FIG. 7, the valve body 8, the core cylinder 9, the urging spring 10, the spring support 11, etc. are inserted from the base end side of the magnetic cylinder 2, and these are inserted. Are disposed at predetermined positions in the magnetic cylinder 2. At this time, for example, the suction portion 8C of the valve body 8 and the core
By changing the size of the gap S between the
Is adjusted to a predetermined size. Further, the seal member 18 and the like are assembled to the magnetic cylinder 2 to complete the injection valve.

Thus, according to the present embodiment, the protector 19 is provided on the outer periphery of the distal end side of the magnetic cylinder 2 using the same resin material as the resin cover 16. Resin cover 1 including connector 17
6 and the protector 19 can be injection-molded together, and the protector 19 can be securely fixed to the outer peripheral side of the magnetic cylinder 2. When the injector is used, the protector 1
9, the seal member 18 can be stably held in the retaining state, and the seal member 18 and the distal end side of the magnetic cylinder 2 can be protected.

In this case, in the injection molding step, the resin molding of the resin cover 16 and the protector 19 and the attachment to the magnetic cylinder 2 can be easily performed in one step.
Therefore, it is not necessary to form the protector 19 as a single part by resin molding or to assemble the protector 19 into the magnetic cylinder 2 by manual work or the like. And the production can be performed efficiently.

The fixing portion 19A of the protector 19 is
Since the boundary position between the magnetic cylinder 2 and the distal end portion 13A1 of the magnetic cover 13 is fixed so as to cover the entire circumference, it is assumed that the boundary between the magnetic cylinder 2 and the magnetic cover 13 is temporarily formed by a bead of the welded portion 14 or the like. Even if there are steps, irregularities, etc., the protector 19 can reliably seal the gap between the magnetic cylinder 2 and the magnetic cover 13. This can prevent foreign matters such as dust and moisture contained in the intake air of the engine from entering between the magnetic cylinder 2 and the magnetic cover 13, thereby improving the durability and reliability.

Also, since the magnetic cylinder 2 is formed integrally with a metal pipe or the like and the thin portion 2C is provided in the middle thereof,
At the time of manufacturing the injection valve, the magnetic cylinder 2 provided with the magnetically interrupted portion can be easily formed simply by performing general-purpose machining such as press working and cutting work on a metal pipe or the like. The total number of parts can be reduced and the structure can be simplified.

Next, FIG. 8 shows a second embodiment according to the present invention. The feature of this embodiment is that a resin ring is provided with a folded portion. Note that, in the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

Reference numeral 31 denotes a protector as a resin ring applied to the fuel injection valve of the present embodiment.
1 is formed in an annular shape using the same resin material as the resin cover 16 by being injection-molded together with the resin cover 16 in an injection molding step, substantially in the same manner as in the first embodiment. It is fixed to the outer periphery of the tip side of the body 2.

However, the protector 31 is annularly fixed to the outer peripheral surface of the magnetic cylindrical body 2, the distal end surface of the magnetic cover 13 and the outer peripheral surface of the welded portion 14 at the inner peripheral side. Portion 31A, a flange-shaped convex portion 31B which is located on the outer peripheral side of the fixing portion 31A and protrudes in the radial direction, and extends between the outer peripheral side and the inner peripheral side of the magnetic cylindrical body 2. An annular folded portion 31 </ b> C that is folded in a substantially U-shape so as to cover the distal end surface and protects the distal end surface of the magnetic cylinder 2.

Thus, also in the present embodiment configured as described above, it is possible to obtain substantially the same operation and effect as in the first embodiment. In the present embodiment, in particular, the protector 31 has a folded portion 31C that covers the front end surface of the magnetic cylinder 2.
Is provided, the protector 31 can protect the distal end side of the magnetic cylindrical body 2 from collision with foreign matter and the like, and the durability can be improved.

Next, FIG. 9 shows a third embodiment according to the present invention. The feature of this embodiment is that the resin cover and the resin ring are integrally molded with resin. Note that, in the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

Reference numeral 41 denotes a protector as a resin ring applied to the fuel injection valve of the present embodiment.
1 is formed in an annular shape using the same resin material as the resin cover 16 by being injection-molded together with the resin cover 16 in an injection molding step, similarly to the first embodiment. 41A and a flange-shaped convex portion 41B.

However, the protector 41 and the resin cover 16
A stepped cylindrical connecting portion 42 for integrally connecting them is provided, and the seal member 18 is mounted in an annular concave groove 43 provided on the outer peripheral side of the connecting portion 42. I have. In the injection molding step, the resin cover 16, the protector 41, and the connecting portion 42 are simultaneously injection-molded in an integrated state.

Thus, also in the present embodiment having such a configuration, it is possible to obtain substantially the same operation and effect as in the first embodiment. In particular, in the present embodiment, since the connecting portion 42 is provided between the resin cover 16 and the protector 41, the resin cover 16, the protector 41, and the connecting portion 42 can be integrally formed of a resin material. Can be fixed to the outer peripheral side of the magnetic cylindrical body 2 in a state where the magnetic cylindrical body 2 is connected to the resin cover 16, and the strength thereof can be further increased to improve the reliability.

In the above embodiment, after the valve seat member 5 is mounted on the magnetic cylinder 2 in the first component mounting process, the injection molding process and the second component mounting process are performed. But
The present invention is not limited to this. For example, the valve seat member 5 is not attached to the magnetic cylinder 2 in the first component assembling step, and the valve seat member 5 is attached to the magnetic cylinder 2 in the second component assembling step. It may be configured to be press-fitted into the inner circumference of the distal end and inserted.

[0066]

As described in detail above, according to the first aspect of the present invention, the resin ring is provided on the outer periphery of the tip end of the magnetic cylinder using the same resin material as the resin cover.
When manufacturing the injection valve, for example, a resin cover and a resin ring can be injection-molded together, and a resin ring for preventing, protecting, etc. various components can be securely fixed to the outer peripheral side of the magnetic cylinder. In addition, since resin molding of the resin cover and resin ring and assembly to the magnetic cylinder can be easily performed in one process, the number of parts required for assembling the injection valve can be reduced, and workability during assembly is improved. And at the same time, it can be manufactured efficiently.

According to the second aspect of the present invention, the resin ring is provided with a folded portion for covering the distal end surface of the magnetic cylinder. Can be protected from collision with the like, and the durability can be improved.

According to the third aspect of the present invention, the resin cover and the resin ring are integrally formed of resin by the connecting portion. , And its strength can be further increased to improve reliability.

Further, according to the fourth aspect of the present invention, the resin ring is configured to cover at least the boundary position between the magnetic cylinder and the front end portion of the magnetic cover. Even when there are minute steps, irregularities, or the like in the position, the boundary position can be reliably sealed by the resin ring, and the durability and reliability can be improved.

According to the fifth aspect of the present invention, the resin ring has a structure in which the sealing member is held at the distal end of the magnetic cylinder in a retaining state. Can be held in a retaining state, and it is possible to prevent the seal member from falling off the magnetic cylinder.

According to the sixth aspect of the present invention, the connector having the terminal pins connected to the electromagnetic actuator is integrally molded with the resin cover, so that the connector of the injection valve, the resin cover and the resin ring are formed. Can be efficiently molded in one step.

On the other hand, according to the manufacturing method of the present invention, the electromagnetic actuator and the valve seat member are assembled on the outer peripheral side of the magnetic cylinder, and these assembled bodies are arranged in the resin mold to form the resin material. The resin cover and the resin ring are molded by injecting the resin, and then the valve body is assembled in the magnetic cylinder. For example, the shape of the resin mold for the resin cover used in the prior art is slightly changed. With only this, the resin cover and the resin ring can be resin-molded in one step and easily assembled to the magnetic cylinder, and the injection valve can be manufactured efficiently.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a fuel injection valve according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged cross-sectional view showing a tip end side of a fuel injection valve.

FIG. 3 is an enlarged cross-sectional view of the fuel injection valve as viewed from a direction indicated by arrows III-III in FIG. 1;

FIG. 4 is an enlarged sectional view of a main part showing a protector and the like provided on the distal end side of a magnetic cylinder.

FIG. 5 is a longitudinal sectional view showing a state in which a valve seat member, an electromagnetic coil, a magnetic cover, a connecting core, and the like are assembled to the magnetic cylinder in a first component assembling step.

FIG. 6 is a longitudinal sectional view showing a state in which a magnetic cylinder or the like is arranged in a resin mold by an injection molding step and a resin cover and a protector are injection-molded.

FIG. 7 is a longitudinal sectional view showing a state in which a valve body, a core cylinder, an urging spring, a spring receiver, and the like are assembled to a magnetic cylinder body in a second component assembling step.

FIG. 8 is an enlarged sectional view of a main part of a protector and the like of a fuel injection valve according to a second embodiment of the present invention, as viewed from the same position as in FIG.

FIG. 9 is a partially enlarged sectional view of the distal end side of a fuel injection valve according to a third embodiment of the present invention, viewed from the same position as in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve casing 2 Magnetic cylinder 2A Valve body accommodating part 2B Core member insertion part 2C Thin part 5 Valve seat member 7 Nozzle plate 8 Valve body 9 Core cylinder 10 Urging spring 12 Electromagnetic coil (electromagnetic actuator) 13 Magnetic cover 13A1 Tip Part 14 Welded part 15 Connection core 16 Resin cover 17 Connector 17A Terminal pin 18 Seal member 19, 31, 41 Protector (resin ring) 19A, 31A, 41A Fixing part 19B, 31B, 41B Flange-shaped convex part 31C Folding part 42 Connecting part

Claims (7)

[Claims] 1. A magnetic cylinder body formed of a magnetic material in a cylindrical shape, a valve seat member provided on an axially distal end side of the magnetic cylinder body and having a valve seat surrounding an injection port, and the magnetic cylinder A valve body displaceably provided in the body and detachably seated on a valve seat of the valve seat member; an electromagnetic actuator provided at an axially intermediate portion of the magnetic cylinder to open the valve body; A fuel injection valve comprising a resin cover covering an outer periphery on a base end side, wherein a resin ring is provided on an outer periphery on a distal end side of the magnetic cylinder using the same resin material as the resin cover. Fuel injection valve. 2. The resin ring is provided with a folded portion that is folded between an outer peripheral side and an inner peripheral side of the magnetic cylinder so as to cover a front end surface of the magnetic cylinder. 2. The fuel injection valve according to 1. 3. A connecting portion for connecting between the resin cover and the resin ring is provided between the resin cover and the resin ring.
3. The fuel injection valve according to claim 1, wherein the resin ring and the connecting portion are integrally formed by resin molding. 4. A magnetic cover which is formed in a cylindrical shape from a magnetic material and which covers an electromagnetic actuator attached to the outer peripheral side of the magnetic cylindrical body from a radially outer side is provided on an outer peripheral side of the magnetic cylindrical body. Is configured such that a distal end portion located closer to the distal end side than the electromagnetic actuator is fitted and attached to the outer peripheral side of the magnetic cylinder, and the resin ring covers at least a boundary position between the magnetic cylinder and the distal end portion of the magnetic cover. The fuel injection valve according to claim 1, 2 or 3, wherein: 5. A sealing member for sealing between the magnetic cylinder and the mounting portion when the magnetic cylinder is mounted on an external mounting portion is provided on the outer periphery of the distal end side of the magnetic cylinder, and the resin ring is provided. 5. The fuel injection valve according to claim 1, wherein the seal member is configured to hold the seal member at a tip end side of the magnetic cylinder in a retaining state. 6. The fuel injection valve according to claim 1, wherein a connector having a terminal pin connected to the electromagnetic actuator is formed integrally with the resin cover by resin molding. 7. An electromagnetic actuator and a valve seat member are mounted on an outer peripheral side of a magnetic cylinder, and an assembly of the magnetic cylinder, the electromagnetic actuator and the valve seat member is disposed in a resin mold. A resin cover that covers the outer periphery on the base end side of the magnetic cylinder and a resin ring located on the outer periphery on the distal end side of the magnetic cylinder are resin-molded by injecting a resin material into the resin material, and thereafter, the inside of the magnetic cylinder is formed. A method for manufacturing a fuel injection valve having a structure in which a valve body is assembled.