JPH0996265A - Bottom feed type solenoid fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the handling of a filter excellent in its mountability by eliminating generation of a burr in a fuel injection valve, when the filter is mounted. SOLUTION: Under a housing H, a valve chamber 20E is drilled in a vertical direction, a fuel hole 20J is opened toward the valve chamber 20E from the outside of the housing H. A valve rod 13 is movably arranged in the valve housing 20E, a valve part 14, opening/closing a seat 8C of a valve seat 8 connected to the valve chamber 20E, is arranged in a lower end of the valve rod 13, and a movable core 15 is arranged in an upper end of the valve rod 13. A tubular filter 30, filtering foreign matter in fuel toward the valve seat 8C from the fuel hole 20J, is arranged in the valve chamber 20E.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic fuel injection valve for use in an electronic fuel injection device, which controls fuel pressurized by a fuel pump and supplies the fuel to an internal combustion engine. A bottom feed type electromagnetic fuel injection valve in which fuel is supplied into a valve chamber from a fuel hole on the lower outside of a housing constituting a fuel injection valve, and the fuel is injected from the valve hole through a valve seat of a valve seat. The present invention relates to a filter for removing foreign matters contained in fuel flowing toward a valve seat in a feed type electromagnetic fuel injection valve.

[0002]

2. Description of the Related Art A bottom feed type electromagnetic fuel injection valve having a conventional filter is disclosed in, for example, Japanese Patent Laid-Open No. 57-2886.
No. 1 publication, etc., of which a representative column will be specifically described with reference to FIG. The housing H is composed of an upper housing 1 and a lower housing 2. The upper housing 1 is closed at the top by the upper bottom portion 1A,
The lower end 1C opens through the locking step 1B. A pipe 1D is integrally formed at the center of the upper bottom portion 1A. The pipe 1D extends at least downward in the upper housing 1, and a lower end 1E of the pipe 1D is at least the same as the locking step portion 1B. Reach the height position. In addition, 1F is a terminal insertion hole provided penetrating the upper bottom part 1A, and two holes are provided on the side of the pipe 1D. In addition, a hole 1G is formed in the pipe 1D so as to pass through the pipe 1D in the vertical direction.
From the upper opening of D to the downward direction, the spring adjusting member 3
Is inserted.

The lower housing 2 has a movable core working chamber 2B formed at an upper end 2A thereof so as to open upward.
A valve seat insertion hole 2D is opened downward at the lower end 2C thereof, and the movable core working chamber 2B and the valve seat insertion hole 2D are communicated by a valve chamber 2E formed vertically. . A first locking step 2F facing upward is formed on the lower bottom of the movable core working chamber 2B, and a second locking step 2G facing downward is formed on the upper bottom of the valve seat insertion hole 2D. To be done. Then, a plurality of fuel holes 2H are formed through the lower outside of the lower housing 2 toward the inside of the valve chamber 2E.

Reference numeral 4 denotes a coil bobbin having a coil 5 wound around its outer circumference. A terminal 4B on one side and a terminal 4C on the other side are arranged so as to project upward in the upper collar 4A, and the one side is provided. The winding start wire of the coil is connected to the terminal 4B, and the winding end wire of the coil is connected to the terminal 4C on the other side. The coil bobbin 4 is arranged inside the upper housing 1 on the outer periphery of the pipe 1D, and at this time, the terminal 4B on one side and the terminal 4C on the other side respectively penetrate the terminal insertion holes 1F and are located above the upper housing 1. It projects upward from the bottom portion 1A. 6 is terminal 4B on one side and terminal 4 on the other side
This is a cover member for preventing the O-ring 7 disposed between C and each terminal insertion hole 1F from coming out of the terminal insertion hole 1F.

A valve hole 8 has a lower end opening at the lower end.
A is a valve seat provided with a valve seat 8C connected to the upper end of the valve seat 8C and connected to a flow path 8B opened at the upper end.
It is inserted and fixed inside. That is, the second opening of the valve seat insertion hole 2D extends from the opening of the lower end 2C of the lower housing 2.
Toward the locking step 2G, the lower valve stem centering member 9,
The valve seat 8, the measuring plate 10, and the annular ring 11 are sequentially inserted, and then the lower end 2C of the lower housing 2 is swaged inward toward the lower end surface of the annular ring 11.

The lower valve rod centering member 9 has
A valve rod guide hole 9A is bored in the center thereof, a flow passage 9B is bored in the side thereof, and a metering hole 10A is bored in the center of the metering plate 10.

According to the above description, the metering hole 10A is provided in the valve chamber 2E of the lower housing 2 through the valve seat 8C and the flow path 8B of the valve seat 8 and the flow path 9B of the lower valve stem centering member 9.
Is contacted.

The first locking step 2F of the lower housing 2
An upper valve rod centering member 11 is disposed above the movable core working chamber 2B, and an upper portion of the upper valve rod centering member 11 is arranged on the press-fitting ring 1
It is press-fitted and fixed by 2. A valve rod guide hole 11A is formed at the center of the upper valve rod centering member 11, and a flow passage 11B is formed through the side of the valve rod guide hole 11A. According to the above, the movable core working chamber 2B and the valve chamber 2E are connected by the flow passage 11B of the upper valve stem centering member 11.

Reference numeral 13 denotes a valve stem which is disposed in the valve chamber 2E and extends in the vertical direction. The valve stem 13 includes a valve stem guide hole 9A of the lower valve stem centering member 9 and a valve stem guide hole 9A of the upper valve stem centering member 11. The centering is supported by the valve stem guide hole 11A so as to be vertically movable.

A valve portion 14 for opening and closing the valve seat 8C is formed at the lower end of the valve rod 13, and an umbrella-shaped movable core 15 facing at least the lower end 1E of the pipe 1D is attached to the upper end. The movable core 15 is in the movable core working chamber 2B.

The valve rod 13, the movable core 15, the valve portion 1
4. The upper part of the lower housing 2 provided with the valve seat 8 is inserted from the opening of the lower end 1C of the upper housing 1 toward the locking step 1B, and then the lower end 1C is inserted toward the lower housing 2. The upper housing 1 and the lower housing 2 were fixed to each other.

Reference numeral 16 denotes a spring contracted between the spring adjusting member 3 and the upper surface of the movable core 15.
When the coil 5 is energized in such a state, the movable core 15 is attracted toward the lower end 1E of the pipe 1D against the spring force of the spring 16, whereby the valve portion 14 opens the valve seat 8C.

Reference numeral 17 denotes a filter, which includes an upper annular frame 17A, a lower annular frame 17B, and an upper annular frame 17A.
And a lower annular frame body 17B, and is formed by a net 17C arranged in a cylindrical shape in the vertical direction. Then, the filter 17 is arranged by being press-fitted into the outer portion of the lower housing 2 where the fuel hole 2H is opened.

According to the above, the foreign matter is removed from the fuel passing through the filter 17 by the net 17C, and this fuel flows through the fuel hole 2H, the valve chamber 2E, the flow passage 9B of the lower valve rod centering member 9, and the valve seat 8. Injection is supplied to the intake pipe and the like through the passage 8B, the valve seat 8C opened by the valve portion 14, the valve hole 8A, and the measuring hole 10A.

[0015]

The conventional bottom feed type electromagnetic fuel injection valve has the following problems. (1) The filter is a lower housing by inserting an inner portion of either one of the upper annular frame body or the lower annular frame body, or both inner side portions of both frame bodies into an outer portion of the lower housing with a fitting margin. Fixedly attached to the outer side of the. Therefore, in order to form the fitting margin, the inner diameter of the inner portion of the annular frame body needs to be formed to be smaller than the outer diameter of the lower housing corresponding to the fitting margin. According to the above,
The outer diameter of the lower housing and the inner diameter of the annular frame need to be accurately formed. Generally, the annular frame of the filter is manufactured by injection molding a synthetic resin material to integrally form a net. However, in order to accurately obtain the accuracy of the inner diameter, its manufacture is extremely difficult. (2) Since the inner portion of the annular frame is fitted to the outer portion of the lower housing with a fitting margin as described above, burrs are generated in this fitting portion, and when the burrs fall off, the fuel hole and the valve chamber There is a risk that the valve may reach the valve seat via the valve and obstruct the obstruction of the valve portion to the valve seat. (3) The filter is arranged on the outer side of the lower housing, and the net is exposed to the outside. According to the above description, the net may be damaged when handling the fuel injection valve, and it is necessary to carefully manage and assemble the fuel injection valve, resulting in poor work efficiency.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and provides a stable valve-closing state without burrs when a filter is mounted, excellent filter mountability, and extremely easy handling. It is a main object to provide a bottom feed type electromagnetic fuel injection valve.

[0017]

According to the bottom feed type electromagnetic fuel injection valve of the present invention, in order to achieve the above-mentioned object, a valve chamber is formed below the housing in the vertical direction and at the same time. A valve rod is movably arranged in the valve chamber, and a valve portion for opening and closing a valve seat of a valve seat formed continuously with the valve chamber is provided at a lower end of the valve rod, and an upper end of the valve rod is provided. A bottom feed type electromagnetic fuel injection valve having a movable core facing at least a lower end of a pipe protruding into the housing space and having a fuel hole opened from the outside of the housing toward the valve chamber, The first feature is that a filter for filtering the fuel flowing from the fuel hole toward the valve seat of the valve seat is arranged in the valve chamber.

According to the bottom feed type electromagnetic fuel injection valve of the present invention, in addition to the first feature, the filter includes an upper annular frame, a lower annular frame, and an upper annular frame. And a tubular mesh disposed between the lower annular frame and the lower annular frame, the filter being formed in the valve chamber, and the lower surface of the lower annular frame is disposed on the valve seat side in the valve chamber. The second feature is that the upper surface of the upper annular frame is disposed in contact with the upper valve stem centering member fixedly disposed near the upper portion in the valve chamber. I do.

[0019]

According to the first feature, since the filter is arranged in the valve chamber, no burr is generated when the filter is attached, and the mesh of the filter is not directly exposed to the outside. It has excellent blockability and can improve its handling and workability. In addition, since the filter is arranged inside the housing, the shape below the fuel injection valve can be particularly reduced.

According to the second feature, the filter is located in the valve chamber, and the annular frame formed in the vertical direction is sandwiched and fixed by the reduction step portion and the upper valve stem centering member. Is not generated, the dimensional accuracy of the filter can be further reduced, and the filter can be manufactured very easily.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the bottom feed type electromagnetic fuel injection valve according to the present invention will be described with reference to FIG. Note that the same components as those in FIG. 3 are denoted by the same reference numerals, and description thereof is omitted. The lower housing 20 is provided with a movable core working chamber 20B in which the movable core 15 can move in the vertical direction and is opened at the upper end 20A so as to open upward.
A valve seat insertion hole 20D is formed at 0C so as to open downward, and the movable core working chamber 20B and the valve seat insertion hole 20D are formed in the valve chamber 2 formed vertically.
Notified by OE. A first locking step 20F facing upward is formed at the lower bottom of the movable core working chamber 20B, and a second locking step 20G facing upward near the lower part of the valve chamber 20E.
Is formed, and a third locking step 20H facing downward is formed at the upper bottom of the valve seat insertion hole 20D. On the other hand, the valve chamber 2
A plurality of fuel holes 20J penetrate and penetrate into 0E. (The second locking step 20G is a reduction step formed on the valve seat 8 side in the valve chamber 20E.)

A filter 30 arranged in the valve chamber 20E
Is formed by: Referring to FIG. 2,
30A is an annular upper frame, and 30B is an annular lower frame. Then, the upper annular frame 30
A and the lower annular frame body 30B are connected by a column 30C, and the inside of the upper annular frame body 30A and the lower annular frame body 30B.
A cylindrical net 30D in the up-down direction is attached to the inside of the. The filter 30 is manufactured by injection-molding a synthetic resin material. At this time, the net 30D is integrally molded at the same time. The outer diameters of the upper and lower annular frames 30A, 30B and the support 30C are preferably smaller than the inner diameter of the valve chamber 20E. Furthermore, the upper surface 30 of the upper annular frame 30A
E On the lower surface 30F of the upper and lower annular frame bodies 30B, annular projecting ribs R protruding from those surfaces are provided.

The following components are assembled to the lower housing 20 as follows. From the lower end 20C of the lower housing 20 to the third locking step 20H in the valve seat insertion hole 20D, the lower valve stem centering member 9, the valve seat 8, the measuring plate 10, and the annular ring 11 are sequentially inserted, Next, the lower end 20 </ b> C of the lower housing 20 is swaged inward toward the annular ring 11. According to the above, the lower valve stem centering member 9, the valve seat 8, the weighing plate 10, and the annular ring 11 are fixedly arranged in the valve seat insertion hole 20D and on the third locking step 20H. The upstream of the flow path 8B of the valve seat 8 is connected to the valve chamber 20E via the flow path 9B of the lower valve stem centering member 9.

Next, the filter 30 is inserted into the valve chamber 20E through the movable core working chamber 20B opened at the upper end 20A of the lower housing 20. According to this, the annular protruding rib R of the lower annular frame body 30B of the filter 30 abuts on the second locking step portion 20G. Next, the upper valve stem centering member 11 is placed on the first locking step 20F of the movable core working chamber 20B.
And press-fit ring 12 is press-fitted into reduced movable core working chamber 20B on its upper surface. According to the above, the lower surface 30F of the lower annular frame 30B of the filter 30
Of the upper annular frame 30A abuts on the lower surface of the upper valve stem centering member 11, and in such a state, the filter 30 is in the valve chamber. Fixed within 20E. And
A valve rod 13 having a movable core 15 and a valve portion 14 is inserted and arranged in a valve rod guide hole 11A of an upper valve rod centering member 11 and a valve rod guide hole 9A of a lower valve rod centering member 9. According to this, the valve portion 14 is connected to the flow path 8 of the valve seat 8.
B, the movable core 1 is disposed so as to face the valve seat 8C.
5 is housed and arranged in the movable core working chamber 20B,
3 is movably centered and arranged.

The upper end 20A of the lower housing 20 is inserted from the lower end 1C toward the locking step 1B of the upper housing 1 in the same manner as in the prior art, and then the lower end 1A.
C is caulked inward toward the lower housing 20, and the assembly of the bottom feed type electromagnetic fuel injection valve is completed. In FIG. 1, a fuel distribution pipe M to which the bottom-feed electromagnetic fuel injection valve is mounted is indicated by a dashed line.

The high-pressure fuel pumped from a fuel pump (not shown) passes through a fuel passage M1 in the fuel distribution pipe M through a fuel hole 20J formed in the lower housing 20 of the bottom feed type electromagnetic fuel injection valve. It is supplied to the inside of the valve chamber 20E.
In the valve chamber 20E, the annular protruding rib R of the upper annular frame 30A of the filter 30 is
1, the annular projecting rib R of the lower annular frame 30B
Is in contact with the second locking step 20G (in other words, the reduction step), the fuel supplied into the valve chamber 20E through the fuel hole 20J is restricted only through the net 30D of the filter 30. This flows into the inside of the room 20E,
When the fuel passes through D, foreign substances contained in the fuel are removed. Therefore, the fuel supplied to the valve seat 8C of the valve seat 8 is only clean fuel that does not contain foreign matter, so that the valve portion 8C can maintain the accurate closing of the valve seat 8C. A bottom-feed electromagnetic fuel injection valve with excellent controllability can be provided. The valve rod 13 and the valve portion 14 may be separate bodies.

[0027]

According to the bottom feed type electromagnetic fuel injection valve of the present invention, the filter 30 has the valve chamber 20.
The upper surface 30E of the upper annular frame body 30A, which is disposed in E
Since the lower surface 30F of the lower annular frame 30B and the lower locking frame portion 20B are planarly pressed and sandwiched by the second locking step portion 20G and the upper valve stem centering member 11, there is no burr when the filter 30 is inserted into the valve chamber 20E. Does not occur. According to the above, clean fuel can be always supplied toward the valve seat 8C, and the valve portion 14 can be satisfactorily kept closed by the valve portion 14.

The height of the filter 30 (corresponding to the height from the upper surface 30E of the upper annular frame 30A to the lower surface of the lower annular frame 30B) is determined by the second locking step 20G and the first locking step. Part 2
The filter 30 can be more easily manufactured since it is sufficient if the depth is larger than the depth of 0F. That is, the filter 30
The variation in height only changes the pressing load of the upper valve stem centering member 11, and does not generate burrs.
Further, when the filter 30 is formed of a synthetic resin material, when the filter 30 is pressed in the vertical direction, the filter 30 bends in the height direction of the filter 30, and
The variation of the height of 0 can be easily absorbed.

Further, since the filter 30 is disposed in the valve chamber 20E, the net 30D is not directly exposed to the outside, so that the handling and management of the bottom feed type electromagnetic fuel injection valve becomes extremely easy. This is particularly effective when the fuel injection valve is mounted on the fuel distribution pipe M.

Furthermore, the filter 30 is disposed vertically in the valve chamber 20E on the outer periphery of the valve rod 13 so that the valve chamber 20E can be effectively used. In particular, the diameter of the lower part of the lower housing 20 is reduced. The diameter can be reduced. Further, the net 30D of the filter 30 can be arranged in a relatively long direction in the vertical direction, which allows a large filtering area of the net 30D to maintain good filtering performance for a long period of time.

When the filter 30 is mounted in the valve chamber 20E, there is no direct contact with the net 30D, so that the net 30D does not peel or break.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a bottom feed type electromagnetic fuel injection valve according to the present invention.

FIG. 2 is a perspective view of the filter in FIG.

FIG. 3 is a longitudinal sectional view showing a conventional bottom feed type electromagnetic fuel injection valve.

[Explanation of symbols]

 H Housing 1 Upper housing 8 Valve seat 8C Valve seat 9 Lower valve stem centering member 10 Pipe 11 Upper valve stem centering member 13 Valve stem 14 Valve portion 15 Movable core 20 Lower housing 20E Valve chamber 20F First locking step 20G Second locking step 20J Fuel hole 30 Filter 30A Upper annular frame 30B Lower annular frame 30D Net

Claims (2)

[Claims] 1. A valve chamber is formed below the housing in the vertical direction, a valve rod is movably disposed in the valve chamber, and the lower end of the valve rod is connected to the valve chamber. A valve seat for opening and closing the valve seat of the valve seat, and a movable core facing the lower end of the pipe protruding into the housing space at least at the upper end of the valve rod. In a bottom feed type electromagnetic fuel injection valve in which a fuel hole is opened toward the bottom, a filter for filtering the fuel flowing from the fuel hole toward the valve seat of the valve seat is arranged in the valve chamber. Bottom feed type electromagnetic fuel injection valve. 2. The filter, comprising: an upper annular frame;
A filter formed by a lower annular frame and a tubular net disposed between the upper annular frame and the lower annular frame and arranged in the vertical direction, and a filter arranged in the valve chamber has a lower annular frame. The lower surface of the frame is disposed in contact with a reduction step formed on the valve seat side in the valve chamber, and the upper surface of the upper annular frame is disposed in contact with the upper valve stem centering member fixedly disposed near the upper portion in the valve chamber. The bottom feed type electromagnetic fuel injection valve according to claim 1, wherein the fuel injection valve is arranged in contact with the bottom feed type.