JPH08312490A - Electromagnetic type fuel injection valve - Google Patents

Abstract

PURPOSE: To reduce pulsation pressure which is generated when the electromagnetic type fuel injection valve is in operation, and also reduce noises of a vehicle which are caused by pulsation pressure. CONSTITUTION: A fuel strainer 4 is disposed at the upstream side of a fuel passage 3A for a fixed core 3 disposed in the longitudinal direction of the electromagnetic type fuel injection valve J, and a measuring injection hole 12C which feeds fuel while injecting it toward an engine, is opened at the lower end of the electromagnetic type fuel injection valve J. An area ratio A/B between the effective area A of a fuel passage 3A in the fixed core 3 and the effective area B of the measuring injection hole 12C shall be in a range of 4<=A/B<=20.

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 used in a fuel injection device, which injects fuel based on an injection signal from an ECU. The electric signal is converted into the fuel flow rate and the fuel is atomized and injected toward the engine.

[0002]

2. Description of the Related Art A conventional electromagnetic fuel injection valve J is shown in FIG. Reference numeral 1 denotes a cylindrical housing having a bottom portion 1A in the vicinity of a lower portion thereof, and an electromagnetic solenoid storage hole 1B is formed so as to extend upward from the bottom portion 1A through a locking step portion 1C, and the bottom portion 1A forms a valve. The sheet storage hole 1D is formed so as to open downward. In addition, a through hole 1E which allows the movement of a plunger described later is formed through the bottom portion 1A. Reference numeral 2 denotes a disc-shaped upper magnetic pole piece arranged on the locking step portion 1C of the housing 1, and a fixed core 3 protruding upward and downward at the center of the upper magnetic pole piece 2.
Is erected. A fuel passage 3A is formed through the fixed core 3 so as to extend along the longitudinal axis of the housing 1. That is, the upper end of the fuel flow path 3A is opened at the upper end of the fixed core 3 projecting upward, and the lower end of the fuel flow path 3A is opened at the lower end of the fixed core 3 projecting downward. The projecting fixed core 3 projects into the electromagnetic solenoid housing hole 1B of the housing 1. A fuel strainer 4 equipped with a filter member 4A such as a mesh or filter paper is installed upstream of the fuel flow passage 3A, and a flow passage 5A penetrates inside the fuel flow passage 3A downstream from the fuel strainer 4. The pipe-shaped inner collar 5 perforated is press-fitted. The bottom portion 1A of the housing 1 described above forms the lower magnetic pole piece 6, and the upper magnetic pole piece 2 and the lower magnetic pole piece 6 are magnetically coupled to the housing 1. Reference numeral 7 denotes an electromagnetic solenoid in which a coil 9 is wound around an outer circumference of a coil bobbin 8. The electromagnetic solenoid 7 projects into an electromagnetic solenoid housing hole 1B of the housing 1, an upper magnetic pole piece 2, a lower magnetic pole piece 6 and downward. It is housed and arranged in a housing space 10 formed by the outer periphery of the fixed core 3. The coil 9 is electrically connected to the terminal 11, and the terminal 11
Protrudes outward through the upper pole piece 2. A valve seat 12A is formed at the lower end of the needle 12, and a needle valve guide hole 12B is opened upward from the valve seat 12A and a metering injection hole 12C is opened downward from the valve seat 12A. The valve seat 12 is a perforated valve seat, and the valve seat 12 is arranged in the valve seat housing hole 1D of the housing 1 so as to be in contact with the lower portion of the lower magnetic pole piece 6 (bottom 1A) via a stopper 13. Reference numeral 14 is a needle valve movably arranged in the needle valve guide hole 12B of the valve seat 12, and a valve portion 14A for opening and closing the valve seat 12A is provided near the lower end of the needle valve, and further below the valve portion 14A. A pintle portion 14B is formed toward the inside of the metering injection hole 12C. On the other hand, a plunger 15 facing the lower end surface of the fixed core 3 is arranged above the needle valve 14. A plunger spring 16 is contracted between the lower end of the inner collar 5 and the plunger 15.
By adjusting the press-fitting depth of the inner collar 5,
Plunger 15 with plunger spring 16
The elastic pressing force on the (needle valve 14) is adjusted.
The locking flange portion 14C provided on the needle valve 14 is arranged with a predetermined gap in the axial direction with respect to the stopper 13, and the valve portion 14A of the needle valve 14 has the valve seat 1
The moving distance in the direction away from the second valve seat 12A is restricted to a predetermined distance.

The electromagnetic fuel injection valve J is incorporated in a fuel injection device as shown in FIG. The electromagnetic fuel injection valve J is mounted on the fuel distribution pipe C, and at this time, the metering injection hole 12C of the electromagnetic fuel injection valve J is connected to the engine D by each intake pipe E.
It is oriented toward the inside. The fuel in the fuel tank F is sucked and discharged by the fuel pump G, and the fuel pressurized by the fuel pump G is supplied into the fuel distribution pipe C through the main filter H and the pulsation damper K. . The fuel supplied into the fuel distribution pipe C is injected into the intake pipe E from the electromagnetic fuel injection valve J based on the injection signal from the ECU, while the remaining fuel in the fuel distribution pipe C is pressure regulator. It is recirculated into the fuel tank F via L.

[0004]

The conventional electromagnetic fuel injection valve as described above has the following problems. When the electromagnetic fuel injection valve J operates in response to the injection signal from the ECU in synchronization with the operation of the engine, the needle valve 14 of the electromagnetic fuel injection valve J
14A of the valve seat intermittently opens and closes the valve seat 12A of the valve seat 12. According to this, in the electromagnetic fuel injection valve J, from the valve seat 12A to the upstream side of the fuel flow path 3A. Pulsating pressure is generated toward. Then, the pulsating pressure of the fuel is transmitted from the fuel distribution pipe C to the vehicle pipe upstream of the fuel distribution pipe C including the pulsation damper K and the main filter H. Although the pulsation pressure is attenuated by the pulsation damper K, the pulsation pressure when the pulsation damper K is not sufficiently attenuated reaches the vehicle pipe or the main filter H further upstream of the pulsation damper K. According to the above, the pulsating radiation sound due to the pulsating pressure is generated in the vehicle piping and the main filter H, and it may be difficult to effectively reduce the noise in the vehicle.

Further, in recent years, the electromagnetic fuel injection valve is required to be miniaturized in order to improve the degree of freedom of mounting on the engine or to reduce the manufacturing cost. By reducing the size of the electromagnetic fuel injection valve, the volume of the fuel flow path formed inside the electromagnetic fuel injection valve is inevitably reduced. Reduction of the pulsating pressure generated in the valve by the damper effect of the fuel in the fuel flow path is hindered. According to the above, it is difficult to reduce noise in the vehicle,
This causes an obstacle in downsizing the electromagnetic fuel injection valve.

The electromagnetic fuel injection valve according to the present invention has been made in view of the above problems, and the pulsating pressure generated in the electromagnetic fuel injection valve during operation of the electromagnetic fuel injection valve is
The main purpose is to reduce the noise inside the electromagnetic fuel injection valve, thereby reducing the noise caused by the pulsating pressure.

[0007]

According to the electromagnetic fuel injection valve of the present invention, in order to achieve the above object, a cylindrical housing in which an upper magnetic pole piece and a lower magnetic pole piece are magnetically coupled and arranged. And at least from the upper pole piece to the lower pole piece,
A fuel flow passage is formed inside the housing and extends along the longitudinal axis of the housing. A fuel strainer is arranged upstream of the fuel flow passage and a fuel flow passage is provided downstream of the fuel strainer. A fixed core in which a pipe-shaped inner collar is provided with a passage penetrating therethrough; it is arranged so as to face the lower magnetic pole piece, and the valve seat and the valve seat are connected and open toward the upper end A valve seat having a needle valve guide hole and a metering injection hole that is connected to the valve seat toward the lower end and opens; a valve seat movably arranged in the needle valve guide hole and facing the fixed core at its upper end A needle valve having a valve section for controlling the opening and closing of a valve seat, and a lower end of which is disposed in a housing space formed by an upper magnetic pole piece, a lower magnetic pole piece, and an inner circumference of the housing. In a fixed core formed downstream of a fuel strainer, in an electromagnetic fuel injection valve including a magnetic solenoid and a plunger spring having a lower end locked to a plunger and an upper end locked to a lower end of an inner collar. The first characteristic is that the area ratio A / B of the effective area A of the fuel flow path of A and the effective area B of the metering injection hole is 4 ≦ A / B ≦ 20.

In addition to the first feature of the present invention, an orifice is formed in the flow passage of the inner collar, and the area ratio A of the effective area A of the orifice and the effective area B of the metering injection hole is A.
The second feature is that / B is set to 4 ≦ A / B ≦ 20.

In addition to the first feature, the present invention provides a tubular collar portion integrally with the fuel strainer on the downstream side of the filter member of the fuel strainer, and uses the tubular collar portion and the fuel flow passage. A third characteristic is that the area ratio A / B between the formed effective area A and the effective area B of the metering injection hole is 4 ≦ A / B ≦ 20.

Further, in addition to the first feature described above, the present invention provides
On the downstream side of the filter member of the fuel strainer, a protrusion that enters into the flow passage of the inner collar is integrally formed with the fuel strainer, and an effective area A formed by the protrusion and the flow passage of the inner collar is measured. Effective area of injection hole B
The fourth characteristic is that the area ratio A / B of and is set to 4 ≦ A / B ≦ 20.

According to the first feature of the electromagnetic fuel injection valve of the present invention, the pulsating pressure generated in the valve portion of the valve seat and flowing into the upstream fuel flow path in the electromagnetic fuel injection valve is fixed core. Since it is throttled by the fuel flow path inside, the pulsating pressure from the electromagnetic fuel injection valve to the outside is greatly reduced, and moreover, it is possible to satisfy the supply of the fully opened flow rate of the electromagnetic fuel injection valve.

According to the second feature of the electromagnetic fuel injection valve of the present invention, since the orifice is formed in the inner collar passage to narrow the fuel passage, the pulsating pressure is reduced by the orifice, and It is not necessary to prepare a new member in order to obtain the throttle of the fuel flow path, and the mounting can be performed simultaneously with the press-fitting of the inner collar. Thus, the above effect can be achieved without increasing the manufacturing cost.

Further, according to the third feature of the electromagnetic fuel injection valve of the present invention, the pulsating pressure is reduced by this throttle because the throttle of the fuel flow passage is formed by the tubular collar portion formed integrally with the fuel strainer. Therefore, the manufacturing cost can be further reduced.

Further, according to the fourth feature of the electromagnetic fuel injection valve of the present invention, the pulsation is formed because the projection of the fuel strainer and the inner collar passage form the throttle of the fuel passage. The pressure is reduced by this diaphragm, and the same effect as the third feature can be achieved.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the electromagnetic fuel injection valve of the present invention will be described below with reference to FIG. It should be noted that the same reference numerals are used for the same structural parts as in FIG. 7, and the description thereof will be omitted.
Comparing FIG. 7 and FIG. 1, the inner colors are different. The inner collar 20 has a pipe shape in which the flow passage 20A penetrates in the longitudinal axis direction, and an orifice 20B is formed at the upper end of the flow passage 20A. This orifice 20B
Are formed at the same time when, for example, lathe processing of the inner collar 20 is performed. The inner collar 20 is inserted into a large-diameter fuel passage 3A opening at the upper end of the fixed core 3 and then press-fitted into a small-diameter fuel passage 3A continuous with the large-diameter fuel passage 3A, and the press-fitting depth is adjusted to adjust the plunger depth. The elastic pressing force of the plunger spring 16 for pressing 15 is adjusted. Then, after adjusting the elastic pressing force of the plunger spring 16 by the inner collar 20, the fuel strainer 4 is press-fitted into the fuel passage 3A having a diameter larger than the upper opening of the fuel passage 3A.

The effective opening area A of the orifice 20B is set as follows. That is, B is the metering injection hole 1
2C is the effective area, and B in this example is the measuring injection hole 1
Since the pintle portion 14B of the needle valve 14 is inserted into 2C, the area of the annular gap formed by the metering injection hole 12C and the pintle portion 14B corresponds to the effective area B of the metering injection hole 12C. Then, the area ratio A / B between the effective area A of the orifice 20B and the measuring injection hole 12C is set to 4 ≦ A / B ≦
Set to 20.

When the engine is operated, the fuel pressurized by the fuel pump G is supplied into the fuel distribution pipe C via the main filter H and the pulsation damper K. The fuel in C is supplied into the electromagnetic fuel injection valve J. In the electromagnetic fuel injection valve J, the fuel flows into the upstream of the fuel flow path 3A through the fuel strainer 4, and the fuel flows from the orifice 20B of the inner collar 20 to the flow path 20A of the inner collar 20.
Downstream of the fuel flow path 3A-gap on the outer circumference of the plunger 15-
It reaches the valve seat 12A of the valve seat 12 through the gap between the needle valve guide hole 12B and the needle valve 14. And
The electromagnetic fuel injection valve J is connected to the ECU in synchronization with the operation of the engine.
The valve portion 14A of the needle valve 14 of the electromagnetic fuel injection valve J intermittently opens / closes the valve seat 12A of the valve seat 12 when operated by the injection signal from the metering injection hole 12C. Fuel corresponding to the injection signal is injected toward the intake pipe E, and pulsating pressure is generated from the valve seat 12A toward the upstream side. The pulsating pressure is transmitted toward the upstream side, which is opposite to the flow of the fuel in the electromagnetic fuel injection valve, and the pulsating pressure is passed from the flow passage 20A of the inner collar 20 to the orifice of the inner collar 20. When it reaches 20B, the flow path 20A becomes an orifice 20B.
Since the passage area is narrowed by, the pulsating pressure is largely attenuated by the orifice 20B.

Pulsating pressure in the fuel passage 3A upstream of the office 20B when the area ratio A / B between the effective area A of the orifice 20B of the inner collar 20 and the effective area B of the metering injection hole 12C is changed. FIG. 2 shows the test results of the relationship with the swing width ΔP of the. According to this, the area ratio A
It was found that when / B is 20 or less, the pulsation pressure can be effectively attenuated, and when the area ratio A / B exceeds 20, the pulsation pressure attenuation effect is reduced. On the other hand, the area ratio A / B
It is possible to effectively obtain the pulsating pressure damping effect even when the value is 4 or less, but when the orifice passage diameters are varied during the manufacture of the orifice 20B, there is a risk that the full-open flow rate will vary. Therefore, the area ratio A / B is preferably 4 or more.

Thus, the pulsating pressure generated in the electromagnetic fuel injection valve is formed in the inner collar 5 by the office 2
It was able to be greatly attenuated by 0B. From the electromagnetic fuel injection valve J to the fuel distribution pipe C and the pulsation damper K,
No large pulsating pressure is transmitted to the vehicle piping including the main filter H. According to the above, the following special effects are exhibited. (1) Since the generation of pulsating radiation sound due to the pulsating pressure can be greatly reduced in the vehicle piping and the main filter H, the noise in the vehicle can be effectively reduced. (2) The pulsation pressure can be greatly reduced by the orifice 20B even when the pulsation suppression effect due to the fuel damper effect is reduced by reducing the volume of the fuel flow path of the electromagnetic fuel injection valve. It is possible to provide an electromagnetic fuel injection valve having a small size and a small size. (3) Since the pulsating pressure from the electromagnetic fuel injection valve to the fuel distribution pipe C and the vehicle pipe upstream thereof can be greatly attenuated, the pulsation damper K can be eliminated. (4) Since it is only necessary to provide the orifice 20B in the flow passage 20A of the inner collar 20, it is not necessary to prepare a new member, and the orifice 20B may be additionally processed when the conventional inner collar 20 is manufactured. Furthermore, since the conventional press-fitting operation of the inner collar 20 can be used, the manufacturing cost of the electromagnetic fuel injection valve hardly increases. (5) The outer shape of the inner collar 20 can be the same as or substantially the same as the inner collar used in the conventional electromagnetic fuel injection valve. Therefore, the outer shape of the electromagnetic fuel injection valve is the conventional one. It is not different from and has compatibility.

Next, a second embodiment of the electromagnetic fuel injection valve of the present invention will be described with reference to FIG. It should be noted that the same reference numerals are used for the same structural parts as in FIG. 7, and the description thereof will be omitted. The fuel strainer is different between FIG. 3 and FIG. 7. That is, the fuel strainer 30 includes a tubular portion 30B having a bottom portion 30A, an enlarged mounting flange portion 30C formed above the tubular portion 30B, and a bottom portion 30 of the tubular portion 30B.
The flow path 3 that opens from A to the upper mounting collar portion 30C
0D, a plurality of communication holes 30E penetrating from the flow path 30D toward the outer periphery of the tubular portion 30B, and the communication holes 30.
And a mesh as the filtering member 31 which is disposed so as to cover E. Further, the outer periphery of the lower portion including the bottom portion 30A of the tubular portion 30B is formed as a reduced diameter portion 30F having a diameter smaller than the outer diameter of the tubular portion 30B. A part of the communication hole 30E covered by the filtering member 31 is the reduced diameter portion 3
Open at 0F. The structure of the fuel strainer 30 described above has the same shape as that of the fuel strainer 4 shown in FIG. 1, but the fuel strainer 30 in the electromagnetic fuel injection valve according to the present invention has the following configuration.

That is, at the lower end of the reduced diameter portion 30F, a reduced diameter portion 30 is provided with a tubular collar portion 30G having a diameter larger than that of the reduced diameter portion 30F and smaller than that of the tubular portion 30B.
Provided integrally with F in series. The diameter of the tubular collar portion 30G will be specifically described later. The tubular collar portion 30G is integrally molded when the fuel strainer 30 is molded with a synthetic resin material. In other words, this tubular collar portion 30G is located on the downstream side of the filtering member 31. This fuel strainer 30 is best understood by referring to FIG.

And, this fuel strainer 30
Is a fuel passage 3 that opens at the upper end of the fixed core 3 after adjusting and press-fitting the inner collar 5 that locks one end of the plunger spring 16 into the fuel passage 3A of the fixed core 3.
Pressed into A. According to the above, the annular gap 32 is formed by the tubular collar portion 30G of the fuel strainer 30 and the fuel flow passage 3A, and the annular gap 32 forms the fuel flow passage. The effective area A is set as follows. That is, B is the effective area of the metering injection hole 12C as described above, and the effective area A of the annular gap 32 is the effective area A of the annular gap 32 and the measuring injection hole 12C.
The area ratio A / B with C is set to 4 ≦ A / B ≦ 20.

When the engine is operated, the fuel pressurized by the fuel pump G is supplied into the fuel distribution pipe C through the main filter H and the pulsation damper K. The fuel in C is supplied into the electromagnetic fuel injection valve J. In the electromagnetic fuel injection valve J, the passage 30D of the fuel strainer 30-the communication hole 30E provided with the filtering member 31-the annular passage formed by the reduced diameter portion 30F and the fuel passage 3A-the cylinder The fuel flows into the upstream of the fuel passage 3A through the annular gap 32 formed by the flange portion 30G and the fuel passage 3A, and the fuel further passes through the passage 20A of the inner collar 20−the fuel passage 3A. Downstream-a gap on the outer periphery of the plunger 15-a gap between the needle valve guide hole 12B and the needle valve 14 to reach the valve seat 12A of the valve seat 12. Then, when the electromagnetic fuel injection valve J operates in response to the injection signal from the ECU in synchronization with the operation of the engine, pulsating pressure is generated from the valve seat 12A toward the upstream side. This pulsating pressure is transmitted toward the upstream side, which is opposite to the flow of the fuel in the electromagnetic fuel injection valve, and this pulsating pressure is transmitted to the fuel strainer 3
When it reaches the annular gap 32 as a fuel flow passage formed by the cylindrical flange portion 30G of 0 and the fuel flow passage 3A, the effective area of this annular gap 32 is specified as in the first embodiment. Since the area ratio (4 ≦ A / B ≦ 20) is set, the pulsating pressure is largely damped by the annular gap 32.

Thus, the same effects as those of the first embodiment can be obtained, and in the implementation thereof, the tubular flange portion 30G is simply provided at the lower end of the conventional fuel strainer.
Can be provided, so that it can be implemented very easily.

Next, a third embodiment of the electromagnetic fuel injection valve of the present invention will be described with reference to FIG. It should be noted that the same reference numerals are used for the same structural parts as in FIG. 7, and the description thereof will be omitted. The fuel strainer differs between FIG. 5 and FIG. 7. That is, the fuel strainer 40 includes a tubular portion 40B having a bottom portion 40A, an enlarged mounting collar portion 40C formed above the tubular portion 40B, and a bottom portion 40 of the tubular portion 40B.
Flow path 4 opening from A toward the upper mounting collar portion 40C
0D, a plurality of communication holes 40E penetrating from the flow channel 40D toward the outer periphery of the tubular portion 40B, and the communication holes 40.
And a mesh serving as a filtering member 41 arranged so as to cover E. Further, the outer periphery of the lower portion including the bottom portion 40A of the tubular portion 40B is formed as a reduced diameter portion 40F having a diameter smaller than the outer diameter of the tubular portion 40B. A part of the communication hole 40E covered by the filter member 41 opens in the reduced diameter portion 40F. The structure of the fuel strainer 40 described above has the same shape as that of the fuel strainer 4 shown in FIG. 1, but the fuel strainer 40 in the electromagnetic fuel injection valve according to the present invention has the following configuration.

That is, a protrusion 40G along the longitudinal axis direction of the fuel strainer 40 is integrally formed by projecting downward from the center of the bottom portion 40A. The protrusion 40G flows through the inner collar 5. It is arranged to enter the road 5A. The diameter of the protrusion 40G will be specifically described later. The protrusion 40G is integrally formed when the fuel strainer 40 is formed of a synthetic resin material. In other words, the protrusion 40G is located downstream of the filtering member 41. The fuel strainer 40 having the protrusion 40G is well understood by referring to FIG.

And this fuel strainer 40
Is a fuel passage 3 that opens at the upper end of the fixed core 3 after adjusting and press-fitting the inner collar 5 that locks one end of the plunger spring 16 into the fuel passage 3A of the fixed core 3.
Pressed into A. According to the above, the projection 40G of the fuel strainer 30 enters the flow passage 5A of the inner collar 5 to form the annular gap 42 by the projection 40G and the flow passage 5A of the inner collar 5. The annular gap 42 forms a fuel flow path, and the effective area A of the fuel flow path is set as follows. That is, B is the effective area of the metering injection hole 12C as described above, and the effective area A of the annular gap 42 is the effective area A of the annular gap 42 and the area ratio A / B of the measuring injection hole 12C being 4 ≤A
Set / B ≦ 20.

When the engine is operated, the fuel pressurized by the fuel pump G is supplied into the fuel distribution pipe C via the main filter H and the pulsation damper K. The fuel in C is supplied into the electromagnetic fuel injection valve J. In the electromagnetic fuel injection valve J, the passage 40D of the fuel strainer 30-the communication hole 40E provided with the filter member 41-the reduced diameter portion 40F and the annular passage formed by the fuel passage 3A Fuel flow path 3
The fuel flows into the upstream of A, and this fuel further includes an annular gap 42 formed by the protrusion 40G of the fuel strainer 40 and the flow passage 5A of the inner collar 5, the flow passage 20A of the inner collar 20, the fuel flow passage 3A. Downstream-gap around the outer periphery of the plunger 15-via the gap between the needle valve guide hole 12B and the needle valve 14, the valve seat 12 of the valve seat 12
Reach A.

When the electromagnetic fuel injection valve J operates in response to the injection signal from the ECU in synchronization with the operation of the engine, pulsating pressure is generated from the valve seat 12A toward the upstream side.
The pulsating pressure is transmitted toward the upstream side, which is opposite to the flow of the fuel in the electromagnetic fuel injection valve, and the pulsating pressure is applied to the protrusion 40 of the fuel strainer 40.
When reaching the annular gap 42 as a fuel flow passage formed by G and the flow passage 5A of the inner collar 5, the effective area of this annular gap 42 is set to the specified area ratio (the same as in the first embodiment). Since 4 ≦ A / B ≦ 20), the pulsating pressure is largely damped by the annular gap 42. Thus, the same effects as those of the first embodiment can be obtained, and the implementation thereof is extremely easy because the projection 40G is simply provided at the lower end of the conventional fuel strainer.

In the above embodiment, the inner collar 20 is the portion where the flow passage that determines the effective area A of the fuel flow passage 3A is narrowed.
Orifice 20B and fuel strainer 30
The tubular flange 30G and the projection 40G of the fuel strainer 40 are formed. However, as long as it is in the fuel flow passage 3A of the fixed core 3, the portion for narrowing the flow passage may be arranged anywhere. Further, although the needle valve of this embodiment has a pintle portion at its lower end, the pintle portion is not always necessary. or,
A ball valve may be used instead of the needle valve.

[0031]

As described above, according to the first feature of the electromagnetic fuel injection valve of the present invention, the effective area A of the fuel flow passage in the fixed core formed on the downstream side of the fuel strainer.
And the area ratio A / B of the effective area B of the measuring injection hole is 4 ≦
Since A / B ≦ 20, the pulsation generated in the electromagnetic fuel injection valve can be greatly reduced, so that the noise generation in the vehicle can be effectively reduced and the electromagnetic fuel injection valve can be downsized. Also in, it is possible to suppress the generation of noise. Further, it is possible to eliminate the pulsation damper arranged in the vehicle piping. According to the second, third and fourth characteristics of the electromagnetic fuel injection valve according to the present invention, the orifice is formed in the flow passage of the inner collar, or the tubular collar portion is provided integrally with the fuel strainer. The effective area A of the fuel passage in the fixed core formed on the downstream side of the fuel strainer and the effective area B of the metering injection hole, Area ratio A / B of 4 ≦ A / B
It is possible to satisfy ≦ 20. According to this, in addition to the above effects, it is not necessary to prepare a special new member,
Further, since no special new assembling work is required, the manufacturing cost is not increased. Further, the fact that the outer shape of the electromagnetic fuel injection valve does not change at all has compatibility with the conventional electromagnetic fuel injection valve.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of an electromagnetic fuel injection valve according to the present invention.

FIG. 2 is a diagram showing a test result of an area ratio A / B between an effective area A of a fuel flow path of a fixed core and an effective area B of a metering injection hole, and a fluctuation width of pulsating pressure.

FIG. 3 is a vertical sectional view showing another embodiment of the electromagnetic fuel injection valve according to the present invention.

FIG. 4 is an enlarged view of a main part of area X in FIG.

FIG. 5 is a vertical sectional view showing still another embodiment of the electromagnetic fuel injection valve according to the present invention.

6 is an enlarged view of a main part of area Y in FIG.

FIG. 7 is a vertical cross-sectional view showing a conventional electromagnetic fuel injection valve.

FIG. 8 is a fuel system diagram showing a state where a fuel injection valve is attached to a fuel injection device of an engine.

[Explanation of Codes] 3 Fixed Core 3A Fuel Flow of Fixed Core 4,30,40 Fuel Strainer 5,20 Inner Collar 5A, 20A Inner Collar Flow Channel 12C Measuring Injection Hole 30G Cylindrical Collar 31,41 Filtering Member 40G Protrusion

Claims (4)

[Claims] 1. A tubular housing in which an upper magnetic pole piece and a lower magnetic pole piece are magnetically coupled and arranged; at least from the upper magnetic pole piece to the lower magnetic pole piece, projecting into the housing, and internally housing A fuel passage is provided along the longitudinal axis direction, a fuel strainer is arranged upstream of the fuel passage, and a pipe is formed through the fuel passage downstream of the fuel strainer. -Shaped inner collar is arranged; a fixed core, which is arranged so as to face the lower magnetic pole piece, a valve seat, a needle valve guide hole which is continuously formed from the valve seat toward the upper end, and opens, and a lower end from the valve seat. A valve seat provided with a metering injection hole that is continuously provided toward the opening; and a plunger that is movably arranged in the needle valve guide hole and that has a plunger facing the fixed core at its upper end and has a lower end at its lower end. Open and close the valve seat A needle valve having a valve portion for controlling; an electromagnetic solenoid disposed in a housing space formed by an upper magnetic pole piece, a lower magnetic pole piece, and an inner circumference of the housing; a lower end locked to a plunger; and an upper end. In an electromagnetic fuel injection valve including a plunger spring locked to the lower end of the inner collar, an effective area A of the fuel flow passage 3A in the fixed core 3 formed on the downstream side of the fuel strainer 4, An electromagnetic fuel injection valve characterized in that the area ratio A / B of the effective area B of the injection hole 12C is 4 ≦ A / B ≦ 20. 2. An orifice 20B is formed in the flow passage 20A of the inner collar, and the area ratio A / B of the effective area A of the orifice 20B and the effective area B of the metering injection hole 12C.
2. 4 ≦ A / B ≦ 20 is set.
The electromagnetic fuel injection valve described. 3. A tubular flange portion 30G is provided integrally with the fuel strainer 30 on the downstream side of the filter member 31 of the fuel strainer, and the tubular flange portion 30G and the fuel passage 3A are provided.
2. The electromagnetic fuel according to claim 1, wherein the area ratio A / B between the effective area A formed by and the effective area B of the metering injection hole 12C is 4 ≦ A / B ≦ 20. Injection valve. 4. A projection 40G that enters into the flow path 5A of the inner collar 5 is formed integrally with the fuel strainer 40 on the downstream side of the filter member 41 of the fuel strainer, and the projection 40G and the inner collar 5 are formed. Effective area A formed by the flow path 5A and the effective area B of the metering injection hole
2. The electromagnetic fuel injection valve according to claim 1, wherein the area ratio A / B of and is set to 4 ≦ A / B ≦ 20.