JPH07167004A - Fuel injection valve - Google Patents

Abstract

PURPOSE:To facilitate the constitution of a dynamic damper, reduce fuel consumption, and optimize an air-fuel ratio by fixing a needle valve with armature via an elastic body when fuel is injected by applying a current to a coil to separate the needle valve from a seat section. CONSTITUTION:When electromagnetic force is produced by applying a current to the coil 19a of a solenoid 19, an armature 10 is attracted to a core 20 against a compression coil spring 24. A fuel injection valve 1 is opened by separating the poppet section 9s of a needle valve body 9 from a seat member 6 in accordance with abutting of the right end section of the armature 10 against the core 20, and fuel is then injected. In this case, an elastic body 15 is filled in both a cavity provided in the needle valve body 9 and a second cavity provided in the armature 10 while being communicated with the aforesaid cavity. By this constitution, both the weight of the armature 10 and the elastic body 15 function as a dynamic damper when a needle valve 8 is closed, so that collision energy when the needle valve 8 is opened/closed is thereby absorbed.

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, and more particularly to a fuel injection valve configured to inject fuel by separating a needle valve from a seat portion by an electromagnetic force of a coil wound around a core.

[0002]

2. Description of the Related Art For example, in an automobile engine, an electromagnetic fuel injection valve is used to inject fuel by separating a needle valve from a seat portion by an electromagnetic force of a coil in order to reduce fuel consumption and optimize an air-fuel ratio. Has been. As an example of this type of fuel injection valve, for example, Japanese Patent Laid-Open Publication No. 2-501804.
The one disclosed in Japanese Patent Publication (the title of the invention, "Dynamic Energy Absorber") is conventionally known.

The dynamic energy absorber of this publication is provided with a damper having an elastomer exterior and a weight attached to the outer surface of the exterior around the mover, and the energy generated by the collision between the mover and the stopper means. Is configured to be consumed by the damper.

[0004]

However, according to the above-described device, the exterior of the elastomer and the weight attached to the outer surface of the exterior are required as new components, which increases the weight and cost of the device. There was a problem.

The present invention has been made in view of the above points, and the needle valve and the armature are fixed via the elastic body, so that the dynamic damper can be configured without requiring new components. The purpose is to do.

[0006]

[Means for Solving the Problems] The above problems can be solved by the following constitution.

That is, a core formed by winding a coil, a seat portion having a hole, a needle valve which is arranged between the core and the seat portion, and includes a needle valve body and a substantially cylindrical armature, A biasing means for biasing the needle valve toward the seat portion is provided, and an electromagnetic force is generated by the coil, so that the needle valve is separated from the seat portion against the biasing force of the biasing means and the fuel is discharged from the hole. In a fuel injection valve for injecting fuel, a needle valve and an armature are fixed by an elastic body.

[0008]

According to the above construction of the present invention in which the needle valve and the armature are fixed via the elastic body, since the elastic body acts as a damper material, when the needle valve collides with the seat portion (needle valve closing At the time), the dynamic damper is constructed by the weight of the armature and the elastic body. Further, when the needle valve collides with the core (when the needle valve is open), the weight of the needle valve body and the elastic body act so as to constitute a dynamic damper.

[0009]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a diagram showing an embodiment of the present invention.

In FIG. 1, a fuel injection valve 1 is an electromagnetic fuel injection valve and is inserted into a mounting hole 2a. The mounting hole 2a is formed in the intake pipe line 2 that communicates with a combustion chamber of an internal combustion engine (not shown).

On the left side of FIG. 1, a nozzle 3 is provided at the tip of the fuel injection valve 1. The left end of the nozzle 3 faces the inside of the intake conduit 2, and the right end of the nozzle 3 is connected to a left end opening of a cylindrical case 4. That is, the flange portion 3a protruding to the outer periphery of the right end of the nozzle 3 is fixed by, for example, caulking while being inserted into the opening of the left end of the case 4.

Further, a concave portion 3b is provided at the right end of the nozzle 3, and a pair of injection ports 3c and 3d are formed in a V shape at the left end of the nozzle 3. These injection ports 3c and 3d
Communicates with the recess 3b inside the nozzle 3 and serves as a fuel passage for injecting fuel pressurized by a pump into the intake pipe line 2 as described later.

The O-ring 5 is fitted in the groove 3e provided on the outer periphery of the nozzle 3 and seals between the mounting hole 2a and the nozzle 3.

The seat member 6 communicates with the projection 6a fitted into the recess 3b of the nozzle 3, the seat 6c communicating with the injection ports 3c and 3d of the nozzle 3 through the hole 6b, and the seat 6c. And a passage 6d bored in the axial direction of the needle valve body 9. An O-ring 7 is fitted in the groove 6e provided on the outer periphery of the sheet member 6. The O-ring 7 seals between the inner wall of the case 4 and the sheet member 6.

The needle valve 8 comprises a needle valve body 9 and an armature 10 having a substantially cylindrical shape, and an elastic body 15 made of a polymer material.
It is connected by. The needle valve element 9 has a conical poppet portion 9a at the left end. The needle valve body 9 is slidably inserted into the passage 6d of the seat member 6. Inside the needle valve body 9, a hollow closing hole 11 extending in the axial direction is formed.

Here, FIG. 2 is a sectional view taken along the line AA in FIG.

The armature 10 is also slidable in the case 4. On the armature 10 side inside the needle valve body 9, a communication hole 12 that is orthogonal to the hollow blocking hole 11 and communicates is formed. Furthermore, the communication hole 12 and the armature 10
An annular recess portion 13 that communicates in the radial direction of the is formed. The hollow block hole 11, the communication hole 12, and the recess 13 make the first
Constitutes the cavity.

On the other hand, on the needle valve body 9 side of the armature 10, an annular recess portion 14 (second cavity) facing the recess portion 13 and communicating therewith is formed. A minute gap δ is provided between the needle valve body 9 and the armature 10 at the portion where the recess 13 and the recess 14 face each other.

The needle valve body 9 with the gap δ maintained
The armature 10 and the armature 10 are set in an injection molding machine, and the elastic body 1 is inserted into the hollow closing hole 11, the communication hole 12, and the recess portions 13 and 14.
5 are infused. At this time, the dimension is such that the elastic body does not protrude from the void δ due to the injection pressure.

The hollow closing hole 11, the communicating hole 12, and the inner walls of the recesses 13 and 14 are respectively V-shaped as shown in the drawing.
The letter-shaped recess 16 is formed obliquely. This recess 16
By providing as many as possible, the fixing strength can be increased. If the fixing strength is not considered so much, the recess 16 need not be provided.

By the way, the front shape of the armature 10 (the shape of the armature as viewed from the tip of the needle valve in the state of FIG. 1) is as shown in FIG. That is, the arc-shaped fuel passages 17a and 1 are provided at four locations on the outer peripheral portion.
7b, 17c and 17d are provided. 18a and 18b and 18c and 18d are communication grooves provided at the ends.

Returning to FIG. 1, the armature 1 will be described.
Communication grooves 18a and 18c, which communicate with the fuel passages 17a and 17c in the radial direction, are formed at the right end portion of 0,
The fuel passage 17a and the communication groove 18a are connected to each other by the fuel passage 17c.
And the communication groove 18c communicate with each other to form a fuel passage.

The solenoid 19 has a coil 19a wound in an annular shape and is housed in the case 4. A cylindrical core 20 is inserted into the through hole 19b of the solenoid 19. An adjusting rod 22 is screwed into and fixed to the inner hollow portion 21 of the core 20. The adjust rod 22 is formed in a cylindrical shape, and a passage 22a for allowing fuel to pass from the right direction penetrates through the inside thereof.

An O-ring 23 is fitted between the left end of the coil 19a, the outer peripheral portion of the left side of the core 20 and the groove 4a of the case 4. The O-ring 23 is formed on the inner wall of the case 4 and the core 20.
Seal between and.

Adjusting rod 22 and armature 10
A compression coil spring 24, which is an urging means, is arranged between and to urge the needle valve 8 toward the seat portion 6c. As a result, the poppet portion 9a of the needle valve body 9 comes into contact with the seat portion 6c of the seat member 6, so that the hole 6b is closed and the fuel injection valve 1 is closed. At this time, the fuel injection to the intake pipe line 2 is stopped.

When the coil 19a is energized to generate an electromagnetic force, the armature 10 is attracted to the core 20 against the biasing force of the compression coil spring 24 to the left. Therefore, as shown in the drawing, the right end portion of the armature 10 abuts on the core 20, while the poppet portion 9a of the needle valve body 9 is separated from the seat portion 6c of the seat member 6 by a predetermined distance, whereby the hole 6b is opened. The injection valve 1 is opened.
At this time, fuel is injected into the intake pipe line 2.

That is, the fuel is supplied from a fuel pump (not shown) to a filter (not shown), the flow path 22a and the communication groove 18a.
And 18c, passages 17a and 17c, passage 6d, hole 6
It is injected into the intake pipe line 2 through b, the injection ports 3c and 3d.

By the way, during the valve opening operation, the right end portion of the armature 10 collides with the core 20, and during the valve closing operation, the poppet portion 9a of the needle valve body 9 contacts the seat portion 6c of the seat member 6. collide.

However, the elastic body 15 is provided in the first cavity provided in the needle valve body 9 and the second cavity provided in the armature 10 in communication with the first cavity.
And the needle valve body 9 and the armature 10 are connected to each other, the elastic body 15 acts as a damper material.

Therefore, the needle valve 8 is installed in the seat portion 6c.
When the armature 10 of the needle valve 8 collides with the core 20 (when the needle valve 8 is opened), the dynamic damper is constituted by the weight of the armature 10 and the elastic body 15. ), The dynamic damper is constituted by the weight of the needle valve body 9 and the elastic body 15. Therefore, the collision energy at the time of opening and closing the needle valve 8 is transmitted to the elastic body 15 as vibrations, which becomes thermal energy to collide. Can absorb energy. Therefore, it is possible to perform a reliable opening / closing operation without bouncing the needle valve at the time of a collision at the time of opening / closing, and to reduce fuel consumption and optimize the air-fuel ratio.

Further, since the first cavity and the second cavity are filled with the elastic body 15 made of a lightweight polymer material, the weight of the device can be reduced as compared with the case of using the metal material. Furthermore, a passage 1 is provided on the outer periphery of the armature 10.
Since 7a to 17d are provided, there is no problem in fuel injection due to residual burr, unlike when a hollow portion is provided inside and used as a passage.

[0032]

As described above, according to the present invention, since the needle valve and the armature are fixed via the elastic body, the weight of the needle valve body, the weight of the armature and the elastic body are used when the needle valve is opened and closed. Since a dynamic damper that acts in both directions of opening and closing the needle valve is configured, it can absorb the collision energy when the needle valve is opened and closed, and can be reliably opened and closed without the needle valve bouncing during a collision, which reduces fuel consumption and emptying. It has the feature that the fuel ratio can be optimized.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view of an essential part of an embodiment of the present invention.

FIG. 3 is a front view of a main part of an embodiment of the present invention.

[Explanation of symbols]

 6c Seat part 6b Hole 8 Needle valve 9 Needle valve body 10 Armature 15 Elastic body 19a Coil 20 Core 24 Compression coil spring 11 Hollow obstruction hole 12 Communication hole 13,14 Recess part

Claims (1)

[Claims] 1. A needle valve comprising a core formed by winding a coil, a seat portion having a hole, a needle valve body disposed between the core portion and the seat portion, and a substantially cylindrical armature. And an urging means for urging the needle valve toward the seat portion, and the electromagnetic force is generated by the coil to resist the urging force of the urging means from the seat portion. A fuel injection valve which separates valves and injects fuel from the hole, wherein the needle valve and the armature are fixed via an elastic body.