JPH10288114A - Electromagnetic fuel injection valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To distribute the fuel to each cylinder uniformly as much as possible and lessen a change in the injection quantity of the fuel due to a change in the intaking negative pressure, which is caused by a change of the engine speed. SOLUTION: A nozzle is punched out from the fuel inlet side so as to restrain the dispersion of the flow quantity (of the fuel) at each jet orifice 5, thereby equalizing the fuel distribution among respective cylinders. In addition, a relational expression N<=0.32X<2> +2.28X (where N denotes a ratio of the volume between a seat part 8a of a nozzle 4 and the jet orifice 5 to the total area of a plurality of jet orifices 5, while X denotes an opening period of a movable valve 3) should be satisfied in order to restrain a change in the injection quantity of the fuel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electromagnetic fuel injection valve.

[0002]

2. Description of the Related Art As a conventional fuel injection method for a multi-cylinder internal combustion engine, there has been a fuel injection valve for each cylinder or a carburetor. The use of an injection valve attached to the apparatus increases the cost of the entire apparatus. In addition, the latter has a problem that it is difficult to uniformly distribute fuel to each intake pipe depending on the shape of the intake pipe and the operating state of the internal combustion engine because the fuel is sprayed at the gathering portion of the intake pipe.

In order to cope with this problem, it is conceivable to inject fuel into a plurality of cylinders with one injection valve whose injection direction is determined corresponding to an intake branch pipe as described in Japanese Patent Publication No. 53-25889. Was done. However, in the fuel injection device configured as described above, there is a problem that fuel cannot be supplied to each cylinder due to an influence of a mounting position of a fuel injection valve, a flow direction of air, a relationship with a fuel injection timing, and the like.

In such a configuration, the pressure of the supplied fuel needs to be more strictly controlled. However, when the negative pressure for controlling the pressure regulator is guided through a long pipe, the pressure loss in the pipe causes a pressure loss. The control negative pressure changes to prevent accurate fuel injection. For this reason, this tube must be as short as possible.

[0005] Therefore, in a fuel injection device of a multi-cylinder internal combustion engine that supplies fuel to a plurality of cylinders with one fuel injection valve, a method and a configuration have been made so that fuel can be distributed to each cylinder as evenly as possible. .

The throttle valve device is attached to the entrance of the collect chamber, and the injection valve is integrally attached to the branch of the intake manifold formed at the exit of the collect chamber. In addition, a mounting seat for mounting an injection valve is formed at a start end position of the branch pipe of the collect chamber, and the injection valve mounted thereon is configured to supply fuel tangentially to a curved portion of the branch pipe. The fuel pressure regulator was integrated with the injection chamber together with the injection valve, and the control pressure of the pressure regulator was taken out of the collection chamber. It was thought to be fixed when the injection valve was installed in the collect chamber.

[0007]

However, if the amount of fuel sprayed by the fuel injector toward each cylinder cannot be made uniform, there is a problem that fuel cannot be evenly distributed to each cylinder. Also, there is a problem that the amount of fuel injection changes due to a change in the suction negative pressure in response to a change in the engine speed, and computer control cannot be performed.

It is an object of the present invention to provide a fuel injection system for a multi-cylinder internal combustion engine that supplies fuel to a plurality of cylinders with one fuel injection valve so that fuel can be distributed to each cylinder as evenly as possible. It is an object of the present invention to provide a fuel injection valve and a method for manufacturing the same, in which the fuel injection amount is less changed due to a change in the suction negative pressure with respect to a change in the rotational speed.

[0009]

In order to achieve the above-mentioned object, according to the present invention, an injection port of a fuel injection valve is punched from a fuel inlet side, a shear surface is formed on a fuel inlet side, and a fracture surface is formed on a fuel outlet side. .

The ratio N (volume between the nozzle seat portion and the orifice / total area of the plurality of injection ports) of the volume between the nozzle seat portion and the orifice and the total area of the plurality of injection ports and the movable valve The relationship of the valve opening time X is N ≦ 0.32X ² +2.78
X.

According to the present invention having the above-described structure, the fuel spray to a plurality of cylinders by one fuel injection valve becomes uniform, the variation in the air / fuel ratio in each cylinder is reduced, and the engine has Drivability is improved.

By determining the ratio of the volume between the seat portion of the nozzle and the orifice and the total area of the plurality of injection ports, the change in the fuel injection amount due to the influence of the suction negative pressure accompanying the change in the engine speed is reduced, and the correction is made. The volume is reduced and computer control becomes possible.

[0013]

FIG. 1 is a partial sectional view of a fuel injection valve 1. FIG.

FIG. 2 shows a state in which the fuel injection valve 1 is attached to the intake pipe 6.

This will be described with reference to FIGS. The main body of the fuel injection valve 1 enters a pressure regulator 2 from a fuel hose (not shown) through a fuel hose, and the fuel is regulated and enters the fuel injection valve 1. The fuel entering the injection valve is moved by an electromagnetic force into a movable valve 3 and A plurality of injection ports 5 provided in the nozzle 4
(5a, 5b, 5c). The injected fuel is distributed to the opening 7 of the intake pipe 6 leading to each cylinder.

FIG. 3 is a sectional view of the nozzle 4 of the fuel injection valve 1 shown in FIG.

FIG. 4 is an enlarged sectional view of the nozzle 4 shown in FIG.

This will be described with reference to FIGS. The injection port 5 provided in the nozzle 4 punches the inner surface 8 forming the injection port 5 formed by cold forging from the fuel inlet side,
The entrance side has a shear surface 5d, and the exit side has a fracture surface 5e.
And the entrance side of the injection port 5 becomes a sharp edge 5f without sagging. Therefore, since the orifice of the sharp edge 5f is measured, the flow rate can be measured well.
Eliminates variations in flow rate.

Further, the injection port 5 having a certain angle θ with respect to the axis of the nozzle 4 facilitates injection into the plurality of openings 7 of the intake pipe 6.

FIG. 5 shows a case where the inner surface 8 forming the injection port 5 of the nozzle 4 has a spherical surface. By making the inner surface 8 a spherical surface, the fuel flowing along the inner surface 8 is not disturbed than the cylindrical one and goes to the injection port 5, so that the flow rate of the fuel exiting from the injection port 5 is stabilized. In addition, since the axis of the injection port is arranged radially from the center of the spherical surface, the punch becomes 90 ° with respect to the tangential direction of the spherical surface when performing the punching process, which facilitates the punching.

FIG. 6 shows a punching die structure of the injection port 5.
The punching of the injection port 5 is performed by guiding the outside of the nozzle 4 with a guide 10, and a die 12 is arranged on the lower surface of the nozzle 4.
Since the sheet portion 8a and the ejection port 5 are integrated, the nozzle 4
The punch 9 entering inside is fixed by the punch holder 11, and punching is performed at a stroke of the angle θ. In order to punch the nozzle 4 from the fuel inlet side, the injection port 5
It is desirably 90 °.

In the case of punching a plurality of injection ports provided at a certain angle with respect to the axis of the electromagnetic fuel injection valve, one of the injection ports is punched and then the other injection port is punched. At the time of ejection, the position of the nozzle is changed, and the other ejection port is punched with the same punch, so that variation in the flow rate of each ejection port can be suppressed.

In this embodiment, in order to make the fuel distributed to the opening 7 uniform, the diameter of the plurality of injection ports 5 provided in the nozzle 4 of the fuel injection valve 1 is the same. In addition, since the punching process is used, the diameter of the injection port 5 is changed by changing the punch diameter, so that the flow rate of fuel distributed to each cylinder can be adjusted and the overall flow rate injected from the plurality of injection ports 5 can be adjusted. Easy to do.

FIG. 7 shows the variation in flow rate when the injection port 5 is punched from the fuel inlet side and when the injection port 5 is punched from the fuel outlet side.

When the injection port 5 is punched from the fuel inlet side, the inlet side of the injection port 5 has a sharp edge 5f without sagging. Therefore, since the orifice of the sharp edge 5f is measured, the flow rate is improved, and the variation of the flow rate is reduced as compared with the case where the fuel is punched from the fuel outlet side.

FIG. 8 shows the ratio N of the volume 13 between the sheet portion 8 of the nozzle 4 and the ejection port 5 to the total area of the plurality of ejection ports 5 (the volume of the volume between the sheet portion 8 of the nozzle 4 and the ejection port 5 / the plurality of ejection ports 5). Injection port 5
Of the movable valve 3 and the valve opening time X of the movable valve 3 are shown.

When the total area of the plurality of injection ports 5 and the opening time of the movable valve 3 are kept constant and the volume 13 between the seat portion 8 of the nozzle 4 and the injection ports 5 is changed, suction from the intake pipe 6 A change in the negative pressure (0 to 600 mmHg) causes a change in the fuel injection amount from the injector 1.

When the total opening area of the plurality of injection ports 5 and the volume 13 between the seat portion 8 of the nozzle 4 and the injection ports 5 are fixed and the opening time X of the movable valve 3 is changed, suction from the intake pipe 6 is performed. A change in the negative pressure (0 to 600 mmHg) causes a change in the fuel injection amount from the injector 1.

When the volume 13 between the seat portion 8 of the nozzle 4 and the injection port 5 and the opening time X of the movable valve 3 are kept constant and the total area of the plurality of injection ports 5 is changed, suction from the intake pipe 6 A change in the negative pressure (0 to 600 mmHg) causes a change in the fuel injection amount from the injector 1.

For this reason, the volume 13 between the seat portion 8 of the nozzle 4 and the injection port 5, the total area of the plurality of injection ports 5, and the movable valve 3
There is a correlation between three of the valve opening times.

The change in the injection amount from the injector 1 with respect to the change in the suction negative pressure (0 to 600 mmHg) is about 10%.
Otherwise, the computer program for driving the injectors becomes complicated and very difficult to control.

Therefore, in order to suppress the change rate of the injection amount of the injector 1 (the change amount is within about 10%), the nozzle 4
The relational expression N ≦ 0.32 between the volume 13 between the seat portion 8 and the injection port 5, the total area of the plurality of injection ports 5, and the opening time of the movable valve 3.
X ² + 2.78X must be satisfied.

[0033]

According to the present invention, even though fuel is injected into a plurality of cylinders by one injection valve, the distribution among the cylinders can be made uniform, and the fuel is injected by a change in the suction negative pressure. It is possible to provide a low-cost fuel injection device with improved operability of the engine while suppressing the change in the amount to within about 10%.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing one embodiment of an injection valve of the present invention.

FIG. 2 is an explanatory diagram showing one embodiment of a fuel injection system configuration using the solenoid valve of the present invention.

FIG. 3 is an explanatory view showing an example of a nozzle portion of the injection valve of the present invention.

FIG. 4 is a partial sectional view showing an example of a nozzle portion of the injection valve of the present invention.

FIG. 5 is a partial sectional view showing an example of a nozzle portion of the injection valve of the present invention.

FIG. 6 is a partial sectional view of a punching die structure of an injection port of a nozzle portion of the injection valve of the present invention.

FIG. 7 is a characteristic diagram of a method of punching an injection valve and a flow rate according to the present invention.

FIG. 8 is a characteristic diagram of a ratio N between the volume between the nozzle seat portion and the orifice of the injection valve of the present invention, the total area of a plurality of injection ports, and the valve opening time of the movable valve.

[Explanation of symbols]

1 ... Injector, 2 ... Pressure regulator, 3 ...
Movable valve, 4 ... nozzle, 5 ... injection port.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenichi Gunji 2477 Takaba, Hitachinaka City, Ibaraki Prefecture Within Hitachi Car Engineering Co., Ltd.

Claims (5)

[Claims] 1. A single injector injects a plurality of cylinders of an engine into a plurality of engine cylinders.
In the electromagnetic fuel injection valve made of parts, the injection port of the electromagnetic fuel injection valve is punched from the fuel inlet side of the seat portion of the nozzle, the inlet side is a shear surface, and the fuel outlet side is a broken surface. An electromagnetic fuel injection valve which is perpendicular to an inner surface forming a downstream of a seat portion of the nozzle. 2. A single injector injects a plurality of cylinders of an engine into a plurality of engine cylinders.
The injection port of the electromagnetic fuel injection valve made of parts is punched out from the fuel inlet side of the seat portion of the nozzle, the inlet side is a shear surface, and the fuel outlet side is a broken surface. An electromagnetic fuel injection valve, wherein an inner surface forming a mouth is spherical. 3. A single injector injects a plurality of cylinders of an engine into a plurality of engine cylinders.
The injection port of the electromagnetic fuel injection valve composed of parts is punched from the fuel inlet side of the seat portion of the nozzle, the inlet side is a shear surface, and the fuel outlet side is a broken surface. On the other hand, an electromagnetic fuel injection valve having a 90 ° nozzle inner surface. 4. A single injector injects a plurality of cylinders of an engine into a plurality of engine cylinders.
The injection port of the electromagnetic fuel injection valve composed of parts is punched from the fuel inlet side of the seat portion of the nozzle, the inlet side is a shear surface, and the fuel outlet side is a fractured surface. When punching a plurality of injection ports whose shaft is provided at a certain angle with respect to the axis of the electromagnetic fuel injection valve, when punching one, and then punching the other injection port,
An electromagnetic fuel injection valve characterized by changing the position of a nozzle and punching the other injection port with the same punch. 5. The nozzle according to claim 1, wherein the ratio between the volume between the seat portion of the nozzle and the orifice and the total area of the plurality of injection ports is N. The relationship between the volume between the orifices / the total area of the plurality of injection ports) and the opening time X of the movable valve is N ≦ 0.32X ² +2.78.
X: an electromagnetic fuel injection valve.