JPH08170570A - Electromagnetic fuel injection valve - Google Patents

Abstract

PURPOSE: To improve the high temperature restarting performance by efficiently replacing vapor in the periphery of the point of a valve with fuel. CONSTITUTION: An electromagnetic fuel injection valve comprises a valve 9 having a valve element part 90 at the point thereof, and a valve seat 8 which has a hollow hole 82 for guiding the valve 9 to be slid in the axial direction and has a jet hole 80 at the tip, which is opened and closed by the valve element part 90, wherein a space part formed between the valve seat 8 and the valve 9 is taken as a fuel passage part 16a. The valve 9 is provided with slide parts 92, 96 having circular outer peripheral surfaces 92a, 96a, which are adapted to slide on the inner peripheral surface of the hollow hole 82 of the valve seat 8. The inner peripheral surface of the hollow hole 82 of the valve seat 8 is provided with plural passage grooves 83 disposed in the circumferential direction extending in the axial direction, and one of the passage grooves is taken as the passage groove 83 positioned on the top when the injection valve is installed in an engine.

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 mainly used in an electronically controlled fuel injection device for a vehicle engine.

[0002]

2. Description of the Related Art A conventional example of an electromagnetic fuel injection valve is shown in FIG.
~ Will be described with reference to FIG. First, an outline of the electromagnetic fuel injection valve will be described based on the cross-sectional view of FIG. The body 1 is made of metal, for example, SUS having magnetism, the hollow portion of the body 1 is made of a magnetic material, and the flange 2a is provided on the outer periphery of the central portion.
The hollow core 2 having the is attached from the rear of the body 1 (right side of FIG. 5). The outer periphery of the first half of the core 2 is made of an electrically insulating material such as synthetic resin and has a coil 5
A bobbin 4 formed by winding a plurality of layers is arranged.

On the outer periphery of the core 2, a power receiving connector 7 into which a terminal 6 electrically connected to the coil 5 is inserted is resin-molded. The connector 7 is resin-molded with, for example, a polyamide resin so as to cover the joint between the body 1 and the core 2. A power feeding connector (not shown) of the electronic control unit is connected to the connector 7, and the coil 5 is energized and deenergized by receiving an input from the electronic control unit.

Inside the front part of the body 1 (left part in FIG. 5), a valve seat 8 having an injection hole 80 is provided.
It is incorporated with. A valve 9 is slidably installed in the hollow portion of the valve seat 8 in the axial direction. A stopper plate 11 that restricts the retracted position of the valve 9 is inserted into the body 1 prior to the valve seat 8. An armature 13 made of a magnetic material is fixed to the rear end of the valve 9. The armature 13 receives a suction force from the core 2 when the coil 5 is energized.

A pipe 14 is press-fitted and fixed in the core 2. A valve spring 15 is incorporated between the pipe 14 and the valve 9. Valve 9
The elasticity of the valve spring 15 always keeps the injection hole 80 of the valve seat 8 closed. In addition,
A fuel passage 16 is formed between the rear end of the core 2 (the right end in FIG. 5) and the injection hole 80 of the valve seat 8. The fuel passage 16 is formed in the rear end of the core 2 corresponding to the inlet of the fuel passage 16. Is equipped with a strainer 17. Also core 2
The rear end portion of the grommet 18 serves as a cushion between the connector 7 and a delivery pipe (not shown).
Is fitted. As is well known, the fuel injection valve is installed with an electric power receiving connector 7 facing upward and an adapter 10 facing obliquely downward with respect to an engine (not shown). When installed on the engine, a white arrow UP in FIG.
The direction indicated by is the heaven direction.

The operation of the thus constructed electromagnetic fuel injection valve will be briefly described. The fuel supplied under a predetermined pressure from a fuel tank (not shown) is filtered by the strainer 17 and then filtered. It reaches the inside of the valve seat 8 through the fuel passage 16. However,
Since the valve 9 is held in a state where the injection hole 80 of the valve seat 8 is closed by the elasticity of the valve spring 15, fuel injection from this injection port 9 does not occur.

When the coil 5 is energized by the input of an electric signal from the electronic control unit, the armature 13 retracts together with the valve 9 by the attraction force of the core 2 as described above. As a result, the valve 9 opens the injection hole 80 of the valve seat 8, and the fuel is injected from there.
Then, when the electric signal to the coil 5 is turned off and the attraction force of the core 2 acting on the armature 13 is released, the elasticity of the valve spring 15 holds the valve 9 again in the state where the injection hole 80 is closed, The fuel injection from this injection port 9 is stopped.

Next, the fuel passage portion (denoted by reference numeral 16a) formed between the valve seat 8 and the valve 9 in the fuel passage 16 will be described in detail with reference to FIGS. 6 and 7. 6 is an enlarged sectional view of a main part, FIG. 7 is a sectional view of the fuel passage portion 16a in each part of FIG. 6, (a) is a sectional view taken along the line AA of FIG. 6, and (b) is a sectional view taken along the line BB. Sectional drawing, (c) the same CC line sectional view, (d) the same DD line sectional view, (e)
Is a sectional view taken along the line EE, and (f) is a sectional view taken along the line FF.
(G) is the same GG line sectional view. The valve 9 has a tapered valve element 90 at its tip, a tip shaft portion 91 continuous with the valve element portion 90, and a slide portion 92 continuous with the tip shaft portion 91 and increasing the shaft diameter. And a passage opening 93 formed by cutting the outer peripheral portion of the slide portion 92 into a width of four faces and opening the slide portion 92 in the axial direction. Further, the valve 9 has a small-diameter shaft portion 94 continuous with the slide portion 92 and a small-diameter shaft portion 9 thereof.
Passage opening 9 similar to the slide portion 92 continuous to 4
5, a slide portion 96, a flange portion 97 that is continuous with the slide portion 96 and has a large shaft diameter, a small diameter shaft portion 98 that is continuous with the flange portion 97, and a mounting portion that is continuous with the small diameter shaft portion 98. 99 is provided.

The cylindrical armature 13 is fitted in the mounting portion 99, and two fuel passages are formed between the mounting portion 99 and the armature 13.
Further, the flange portion 97 is located on the front side of the stopper plate 11, and the contact with the stopper plate 11 limits the retracted position when the valve 9 moves forward and backward in the axial direction. The stopper plate 11 has a substantially C-ring shape, and its inner diameter is the flange portion 97 of the valve 9.
It is larger than the shaft diameter of the small diameter shaft portion 98 between the mounting portion 99 and the mounting portion 99, and smaller than the outer diameter of the flange portion 97. Further, the opening 12 of the stopper plate 11 functions as a fuel passage as well as a passage when the small diameter shaft portion 98 of the valve 9 is assembled. Further, in FIG. 7 (g), among the double circles of two large and small two-dot chain lines, the inner circle shows the outer diameter of the flange portion 97, and the outer circle shows the inner diameter of the large diameter hole portion 82a described later,
The overlapping portion between the double circle and the opening portion 12 (the hatched portion of the chain double-dashed line) indicates a fuel passage that is always in communication regardless of whether the valve 9 is open or closed.

The valve seat 8 has a hollow hole 82 for slidingly guiding the outer peripheral surfaces of the slide portions 92 and 96 of the valve 9, and a valve portion 90 which is continuous with the tip of the hollow hole 82 and which is separated from the valve portion 90. A tapered seat hole 81 and a small diameter injection hole 80 of the seat hole 81 are provided. In addition, the flange portion 9 of the valve 9 is provided at the rear end of the hollow hole 82.
A large-diameter hole portion 82a that allows the movement of 7 is formed.
As an electromagnetic fuel injection valve of the type described above, there is, for example, Japanese Patent Publication No. 1-41828.

[0011]

According to the conventional electromagnetic fuel injection valve, in the slide portions 92 and 96 of the valve 9, as shown in FIGS. The outer peripheral surface of 96 is slid and guided by the inner peripheral surface of the hollow hole 82 of the valve seat 8, while the fuel passage is formed by the passage opening portions 93 and 95 provided intermittently in the circumferential direction of the slide portions 92 and 96. ing.

However, since the valve 9 is inserted into the hollow hole 82 of the valve seat 8 without being aligned in the axial direction, either of the passage openings 93, 9 is formed.
5 is not always located in the upper direction when installed in the engine, and any passage opening 9 is not installed when assembled.
Even if 3, 95 are inserted so as to be positioned in the top direction, the opening / closing operation causes a slight rotation in the axial direction, and the passage openings 93, 95 are not maintained in the top direction (FIGS. 6 and 7).
(See (d) and (f)). Therefore, even if the vapor generated around the tip portion of the valve 9 tries to float along the ceiling portion of the inner peripheral surface of the valve seat 8, the slide portions 92, 9
4 (mainly the slide portion 92 on the front side), and even if the fuel tries to drop toward the valve tip end due to the floating of the vapor, the slide portions 92, 94
Will be blocked by. Then, since the vapor and the fuel are not efficiently replaced around the tip of the valve 9, the vapor easily collects around the tip of the valve 9, and the restartability is poor due to vapor lock under bad conditions such as high temperature. Is expected to be caused.

The technical problem to be solved by the present invention is as follows.
An object of the present invention is to provide an electromagnetic fuel injection valve capable of improving the high temperature restartability by efficiently replacing the vapor around the tip of the valve with fuel.

[0014]

In order to solve the above-mentioned problems, the invention according to claim 1 has a valve having a valve element at its tip and a hollow hole for slidingly guiding the valve in the axial direction and at its tip. A valve seat having an injection hole that is opened and closed by the valve element, and an electromagnetic fuel injection valve having a space formed between the valve seat and the valve as a fuel passage part, wherein the valve has a valve seat A slide portion having a circular outer peripheral surface that slides on the inner peripheral surface of the hollow hole is provided, and a plurality of passage grooves extending in the axial direction are provided in the inner peripheral surface of the hollow hole of the valve seat in the circumferential direction. It is an electromagnetic fuel injection valve, one of which has a passage groove located in the top direction when the injection valve is installed in the engine. Claim 2
The invention of claim 1 provides a plurality of openings in the circumferential direction of the stopper plate that regulates the retracted position of the valve, and one of the openings is an opening that is located in the top direction when the injection valve is installed in the engine. It is the electromagnetic fuel injection valve according to 1.

[0015]

According to the electromagnetic fuel injection valve of the invention of claim 1,
When the injection valve is installed in the engine, one passage groove of the valve seat is located in the top direction, and the other passage grooves are located in the ground direction. Therefore, the vapor generated around the tip of the valve can be quickly floated along the passage groove located in the top direction of the valve seat, and along with the vaporization, the fuel can be quickly moved from the other passage grooves toward the tip of the valve. The vapor around the tip of the valve can be efficiently replaced with fuel. According to the electromagnetic fuel injection valve of the second aspect of the invention, one opening of the stopper plate is located in the top direction, and the other openings are located in the ground direction rather than that. Therefore, even in the stopper plate, the vapor is effectively floated and the fuel is dropped, so that the vapor-fuel replacement efficiency is further improved.

[0016]

EXAMPLES Examples will be described with reference to FIGS. 1 and 2. Since this example is a modification of a part of the conventional example, the modified part will be described in detail, and the same parts as those of the conventional example will be designated by the same reference numerals in the drawings and duplicate description will be omitted.
1 is an enlarged cross-sectional view of an essential part of the electromagnetic fuel injection valve, and FIG. 2 is FIG.
6A is a cross-sectional view of the fuel passage portion 16a in each part of FIG. 6, FIG. 6A is a cross-sectional view taken along the line AA of FIG. 6, and FIG.
(C) is the same CC sectional view, (d) is the same DD sectional view, (e) is the same EE sectional view, (f) is the same FF sectional view, (g) ) Is a sectional view taken along line GG. In the valve 9, the slide portions 92, 96 are formed into a disc shape whose outer peripheral portions are not cut off, so that the passage opening portions 93, 96
95 is abolished, and it is a slide portion having circular outer peripheral surfaces 92a and 96a (see FIGS. 2D and 2F).

Further, in the valve seat 8, the hollow hole 8
The inner peripheral surface of 2 has a proper number extending in its axial direction, in this example 4
Book passage grooves 83 are formed at equal intervals in the circumferential direction. One of these passage grooves 83 is located in the top direction (see arrow UP in FIG. 1) when the injection valve is installed in the engine. Passage groove 83
Can be easily formed, for example, by cold forging.

As shown in FIGS. 1 and 2 (g), the stopper plate 11 is formed with a U-groove opening 12a at a position symmetrical to the opening 12 so that the U-shaped opening 12a extends in the circumferential direction. A plurality of openings are provided. One of the openings 12, 12a is located in the top direction (the direction of arrow UP in FIG. 1) when the injection valve is installed in the engine. In FIG. 2 (g), the overlapped portion between the large and small two-dot chain line double circles and the openings 12 and 12b (hatched portion of the two-dot chain line) always communicates with the fuel regardless of whether the valve 9 is opened or closed. Shows the passage.

The valve seat 8 and the stopper plate 11 are connected to the body 1 when the power receiving connector 7 is oriented in the upward direction when the injection valve is installed in an engine, for example. It is assembled so that one passage groove 83 and the opening 12a are located on seven sides. For example, the position of the valve seat 8 and the stopper plate 11 is indexed by the image processing device, and the automatic assembling device performs a predetermined assembling process based on the indexed position, so that the valve seat 8 and the stopper plate 11 are attached to the body 1. It can be assembled in a state where 11 is aligned.

According to the electromagnetic fuel injection valve, when the injection valve is installed in the engine, one passage groove 83 of the valve seat 8 is located in the top direction and the other passage grooves 83 are located in the ground direction. To do. Therefore, the vapor generated around the tip end portion of the valve 9 can be quickly floated along the passage groove 83 located in the top direction of the valve seat 8, and along with the vaporization, fuel is flown from the other passage groove 83 toward the valve tip end portion. The vapor around the tip portion of the valve 9 can be efficiently replaced with the fuel, because the vapor can be quickly lowered toward the. Therefore, the vapor lock can be prevented or reduced, and the high temperature restartability can be improved.

Further, one opening 12a of the stopper plate 11 is located in the top direction, and the other openings 12 are located in the ground direction more than that. Therefore, the vaporization of the vapor and the descent of the fuel are also effectively performed in the stopper plate 11, so that the efficiency of replacing the vapor with the fuel is further improved, which is effective in preventing or reducing the vapor lock.
Since the stopper plate 9 has been conventionally inserted into the body 1 without being aligned in the axial direction, the opening 12 is rarely positioned in the upward direction when installed on the engine, and may prevent the vaporization of the vapor. In addition, even if the openings 12 are located in the upper direction when the engine is installed and the vapor can float, there is no opening for allowing the fuel to drop, so the replacement efficiency of the vapor and the fuel is ultimately high. However, according to this example, such a defect is improved.

As shown in the front view of FIG. 3, the stopper plate 11 has a plurality of U-groove-shaped openings 12a (two are shown in the drawing), and together with the openings 12, X is formed in the circumferential direction. A plurality of them may be provided at equal intervals in the circumferential direction. Also in this case, one of the three openings 12 and 12a is attached to the body 1 so that the opening is located in the top direction when the injection valve is installed in the engine. In addition, the U-shaped opening 1
It is also conceivable to form the opening 12b shown in the explanatory view of FIG. 4 instead of 2a. That is, this opening 12b
Is formed in a notched shape on the inner peripheral portion of the front surface (the surface on the valve seat side) of the stopper plate 11 as shown in the sectional view in FIG. 4A, and is shown in the front view in FIG. 4B. One may be provided at a position symmetrical with the opening 12 as described above, or a plurality (two in the figure) may be provided as shown in the front view in FIG. It should be noted that the flow of fuel is indicated by arrows in FIG.

[0023]

According to the electromagnetic fuel injection valve of the first aspect of the present invention, by providing a plurality of passage grooves on the inner peripheral surface of the hollow hole of the valve seat, the vapor around the tip of the valve can be efficiently used as fuel. It can be replaced well, and therefore vapor lock can be prevented or reduced, and improvement in high temperature restartability can be realized. Further, unlike the conventional case where a passage opening as a fuel passage is provided on the valve side, a passage groove as a fuel passage is provided on the valve seat side fixed to the injection valve body side, so that the passage groove to the engine is provided. Since it can be always positioned in the top direction at the time of installation and its position does not change even after assembly, the above effect can be reliably and permanently obtained. According to the electromagnetic fuel injection valve of the invention of claim 2, since the stopper plate is also provided with a plurality of openings, the efficiency of vapor and fuel replacement is further improved, which is effective in preventing or reducing vapor lock. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a main part of an embodiment.

FIG. 2 is a cross-sectional view showing a fuel passage portion in each portion of FIG.

FIG. 3 is a front view showing another example of a stopper plate.

FIG. 4 is an explanatory view showing another example of the stopper plate.

FIG. 5 is a cross-sectional view showing an electromagnetic fuel injection valve.

FIG. 6 is a sectional view showing a main part of a conventional example.

7 is a sectional view showing a fuel passage portion in each portion of FIG.

[Explanation of Codes] 9 Valve 90 Valve part 92, 96 Slide part 92a, 96a Circular outer peripheral surface 8 Valve seat 80 Injection hole 82 Hollow hole 83 Passage groove 11 Stopper plate 12, 12a, 12b Opening part 16a Fuel passage part

[Procedure amendment]

[Submission date] January 12, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0005

[Correction method] Change

[Correction content]

A pipe 14 is inserted in the core 2 ,
It is fixed by caulking the core 2 . A valve spring 15 is incorporated between the pipe 14 and the valve 9. Due to the elasticity of the valve spring 15, the valve 9 is always held in a state where the injection hole 80 of the valve seat 8 is closed. A fuel passage 16 is formed between the rear end of the core 2 (right end in FIG. 5) and the injection hole 80 of the valve seat 8, and the rear end of the core 2 corresponding to the inlet of the fuel passage 16 is formed. A strainer 17 is incorporated in the section. At the rear end of the core 2,
A grommet 18 having a cushioning function is fitted between the connector 7 and a delivery pipe (not shown). The fuel injection valve should be installed in the engine in a certain direction.
Is installed, and its direction differs from engine to engine, but is generally
As is well known, the power receiving connector 7 is installed upward and the adapter 10 is installed obliquely downward with respect to an engine (not shown).
The direction indicated by the white arrow UP is the upward direction.

Claims (2)

[Claims] 1. A valve seat having a valve portion at a tip portion thereof, and a valve seat having a hollow hole for slidingly guiding the valve in the axial direction and having at its tip end an injection hole opened and closed by the valve portion. In an electromagnetic fuel injection valve in which a fuel passage is a space formed between a valve seat and a valve, the valve has a circular outer peripheral surface that slides on an inner peripheral surface of a hollow hole of the valve seat. And a plurality of passage grooves extending in the axial direction are provided in the inner peripheral surface of the hollow hole of the valve seat in the circumferential direction, and one of them is provided in the upward direction when the injection valve is installed in the engine. An electromagnetic fuel injection valve characterized by having a groove. 2. The stopper plate for restricting the retreat position of the valve is provided with a plurality of openings in its circumferential direction, and one of the openings is an opening located in the top direction when the injection valve is installed in the engine. The electromagnetic fuel injection valve according to claim 1, wherein: