JPH03281978A - Electromagnetic fuel injection valve - Google Patents

Abstract

PURPOSE:To minimize the particle size of atomized fuel by feeding air out of air feed passages provided for the specified positions of an adapter onto fuel injected out of a valve port in a state that the turbulence of fuel injected out of the valve port is restrained. CONSTITUTION:An electromagnetic fuel injection valve 5 which opens/closes its fuel injection valve port 10 formed on a valve main body 9 by means of the reciprocal movement of a bar shaped movable valve 8 caused by both of the energizing force of a spring 6 and the attractive force of an electromagnetic coil 7, is mounted onto an inlet air duct while fuel injection is directed to an inlet air port, and both of its valve seat 11 ranged to the valve port 10 and the tip end section of the movable valve 8 are formed into a conical shape. And an adapter 12 formed with a cylindrical hole 13 which restrains fuel injected out of the valve port 10 from being spreaded, is mounted onto the end face of the valve main body 9, and the adapter 12 is formed with a plurality of air feed passages 14. In this case, the direction of each air passage 14 is fairly shifted from the axial center of the guide hole 13 so as to be off-set by (e) so that an unequality of e<(A+d)/2 is satisfied where (d) represents the diameter of the valve port 10, and A represents the diameter of each air passage 14.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improved atomization structure for an electromagnetic fuel injection valve that injects and supplies fuel to an automobile engine.

(Prior Art) Conventionally, as shown in FIG.
The movable valve 105 that opens and closes the valve hole 103 by contacting the valve seat 104 connected to the valve hole 103 formed in the valve body 102 of the valve body 102 is suitable for boat fishing, as it can easily obtain hardness and high accuracy. It is made into a spherical shape.

(Problem to be Solved by the Invention) In this case, although the electromagnetic fuel injection valve 101 has excellent opening/closing accuracy and durability, turbulent parts are likely to occur in the jet flow, and the fuel scattered due to the turbulence is The guide hole 107 of the adapter 106 attached to the tip, in this case,
It adheres to the inside of the guide hole 107 formed in the adapter 106 in order to restrict the spread of the fuel injected from the valve hole 103.
This attached fuel accumulates and falls from the end of the guide hole 107, causing fuel dripping, which worsens the exhaust gas and causes instability in engine rotation.

Therefore, an object of the present invention is to obtain stable atomized fuel by blowing air onto the fuel injected from the valve hole while preventing disturbance of the fuel injected from the valve hole, and to improve the atomization of this fuel. It is an object of the present invention to provide an electromagnetic fuel injection valve that can more significantly improve and stabilize engine operating characteristics.

(Means for Solving the Problems) That is, the present invention provides an electromagnetic type that opens and closes a fuel injection valve hole formed in a valve body by reciprocating a rod-shaped movable valve due to the urging force of a spring and the attractive force of an electromagnetic coil. In the fuel injection valve, the valve seat connected to the valve hole and the movable valve tip that abuts the valve seat are both formed into a conical shape, and the valve seat and the movable valve are connected to each other by a ring with a large diameter part of the double chain cone. Further, an adapter having a guide hole formed in the tip of the valve body for regulating the spread of fuel injected from the valve hole is attached to the tip of the valve body, and a guide hole is formed in the adapter so as to intersect with the guide hole. an air supply passage for supplying air for promoting atomization of the injected fuel to the guide hole, and an axial extension of the air supply passage is slightly shifted from the axis of the guide hole to supply the air. The passage has an offset amount e, and the offset amount e, the diameter d of the valve hole, and the diameter A of the air supply passage
It is located in the electromagnetic fuel injection valve set to.

(Function) In the electromagnetic fuel injection valve configured as described above, when the electromagnetic coil is excited, the movable valve moves by suction against the spring biasing force, the movable valve separates from the valve seat, and the valve opens. Fuel is injected from the hole, but the fuel is rectified on the conical surface formed by the valve seat connected to the valve hole and the tip of the movable valve, and is injected from the valve hole to the guide hole of the adapter in an undisturbed state. In other words, the fuel is injected in a constant attitude without changing even when the fuel pressure fluctuates or the flow rate changes.

In this way, fuel is injected into the guide hole in a constant position, and air is blown from the side onto this atomized fuel in a constant position.
Atomization of the injected fuel is further promoted in a stable state, and
This atomized atomized fuel is produced by slightly shifting the axial extension line position of the air supply passage from the axis of the guide hole to give the air supply passage an offset amount e;
Since the settings are as described above, the atomization of the sprayed fuel is further promoted, and the actual measurement results show that the diameter of the sprayed particles of the sprayed fuel can be minimized as shown in FIG. 1O.

(Effects of the Invention) As a result, the present invention supplies stable atomized fuel to the engine while preventing disturbance of the fuel injected from the valve hole, purifies and stabilizes exhaust gas, and By effectively preventing engine rotation instability caused by supply irregularities and by minimizing the atomized particle size of the atomized fuel injected from the guide hole, combustion efficiency is improved.
This has the effect of further improving the operating characteristics of the engine.

(Embodiment) Next, the configuration of an embodiment of the present invention will be described with reference to FIGS. 1 to 15.

As shown in FIGS. 1 and 2, cylinder 2 of engine I
At a position corresponding to each cylinder 2 separate intake pipe 4 of the fuel delivery pipe 3 arranged in the arrangement direction, an electromagnetic fuel injection valve 5, in this case, a rod-shaped fuel injection valve 5 due to the urging force of the spring 6 and the attraction force of the electromagnetic coil 7 is installed. An electromagnetic fuel injection valve 5 that opens and closes a fuel injection valve hole 10 formed in a valve body 9 by reciprocating motion of a movable valve 8 is installed with its fuel injection direction facing the intake port, and is inserted into the valve hole 10. Continuous valve seat 1
1 and the tip of the movable valve 8 that contacts the valve seat 11 are the third
As shown in the figure, the valve seat 11 and the movable valve 8 are formed in a conical shape, and the valve seat 11 and the movable valve 8 are brought into contact with each other in a ring shape in a substantially line contact state at the large diameter part of the cone, and the fuel delivery pipe 3 The attached electromagnetic fuel injection valve 5 has an adapter 12 formed on the end face of the valve body 9, in this case a cylindrical guide hole 13 for regulating the spread of fuel injected from the valve hole IO at the tip of the valve body 9. It is attached to the separate intake pipe 4 of each cylinder 2 via an adapter 12, and the adapter 12 has an air supply for supplying air for promoting atomization of the injected fuel to the guide hole 13, crossing the guide hole 13, for example, orthogonally to the guide hole 13. One passage 14 is formed around the guide hole 13 as shown in FIG. 4, or a plurality of passages 14 are formed at arbitrary intervals around the guide hole 13 as shown in FIG. 15 is chamfered as shown in FIG. 6 and rounded as shown in FIG. 7 to prevent adhering fuel from accumulating and dripping or dripping, and the guide hole 13 has a cylindrical shape as well as a shape that widens at the end as shown in FIG. 8. Guide hole 1
It can be of any shape such as 6.

In this case, the direction of the air supply passage 14 formed in the guide hole 13, 16 is slightly shifted from the axis of the guide hole 13, J6 to have an offset amount e to further promote atomization of the sprayed fuel. and the diameter of the valve hole lO is d,
When the air supply passage 14 is
It becomes the smallest as shown in diagram O.

Next, the operation of this embodiment will be explained.

In the electromagnetic fuel injection valve 5 configured as described above, when the electromagnetic coil 7 is excited, the movable valve 8 is attracted and moved against the biasing force of the spring 6, and the movable valve 8 is separated from the valve seat 11, and the valve is closed. opens, and fuel flows out from the valve hole 10.
As shown in Figure 1, the fuel is injected without turbulence, that is, the fuel flows from the valve hole 10 to the adapter in a rectified form on the conical surface formed by the valve seat 11 connected to the valve hole 1o and the tip of the movable valve 8. 12 guide holes 13 in an undisturbed state, for example,
The fuel is injected in a constant position, regardless of fluctuations in fuel pressure or flow rate.

In this way, the fuel from the valve hole lO flows into the guide hole 13 in the 11th direction.
As shown in the figure, the atomized fuel is injected in a nearly constant attitude, and the atomized fuel in this constant injection attitude is either air from the bypass passage 18 that has bypassed the intake passage 17 or air from the lateral air supply passage 14.
Since the injected fuel is sprayed from
As shown in FIG. 9, by slightly offsetting the orientation of each air supply passage 14 from the axis of the guide hole 13 to have an offset amount e, atomization of the atomized fuel is further promoted, and as a result, Atomized fuel that is more atomized than the atomized fuel injected from the valve hole 10 is stably supplied to the engine 1, improving the combustion efficiency of the engine-supplied fuel and preventing deterioration of exhaust gas. At the same time, destabilization of engine rotation due to irregular fuel supply is also effectively prevented.

Next, in FIGS. 12 and 13, an air supply passage 19 is formed obliquely in the adapter 12 instead of the air supply passage 14 of the above embodiment, and air is supplied toward the downstream of the guide hole 13. Compared to the fuel injection state in which it was relatively difficult to spread when no air was supplied, the fuel injection state when air was supplied was improved as shown in Fig. 13, and the spray angle θ of the atomized fuel was improved.
can be set to, for example, 60° or less, and in this case, the diameter of the groove guide hole 13 shown in FIG. The spray angle θ of the atomized fuel can be changed as shown in FIG. 14 by adjusting the angle.

Next, FIG. 15 shows each air supply passage 14.1 of the above embodiment.
For example, the vertical cross-sectional shape of the air supply passage 20 corresponding to 9 is widened toward the downstream, and the air supply passage 17
The air supplied to the air supply passage 20 through the bypass passage 18 is heated by the heater 21 installed in the bypass passage 18 so that the high-temperature air spreads over the sprayed fuel in the guide hole 13 and is supplied. As a result, air is blown while efficiently heating the entire sprayed fuel within the narrow guide hole 13, which atomizes the sprayed fuel and further promotes atomization, improving combustion efficiency and reducing engine exhaust gas. More reliably prevent gas deterioration, and
It is also possible to more reliably prevent engine rotation from becoming unstable due to irregular fuel supply.

Note that the air supply to the guide holes 13.16 shown in FIGS. 1 to 13 can be all heated air shown in FIG. The air supply passage 14.1 formed in the adapter 12 has been experimentally tested.
There is data that indicates that atomization is further promoted when there is a plurality of 9.20s rather than one, and there are also The effects of each of the above embodiments can be made even more noticeable by applying surface treatment such as Teflon coating or mirror finishing to reduce the surface tension and prevent fuel from adhering and to make the flow of the atomized fuel smooth. can do.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the entire embodiment of the present invention, FIG. 2 is an enlarged view of the main part of FIG. 1, FIG. 3 is an explanatory diagram of the valve seat 11 portion, and FIGS. 4 and 5. Figures 8, 12, and 15 are detailed views of the main parts of the fuel injection part, Figures 6 and 7 are enlarged views of the end face of the adapter 12, and Figure 9 is an offset e.
FIG. 10 is a characteristic diagram showing fuel spray particle size data corresponding to off-cella) e, FIG. 11 and FIG. 13 are explanatory diagrams showing the fuel injection state, FIG. 14 is a characteristic diagram showing the fuel injection angle data,
FIG. 16 is an explanatory diagram of a conventional embodiment. 5: Electromagnetic fuel injection valve 6: Cylinder 7: Electromagnetic coil 8: Movable valve 9: Valve body 10: Valve hole 11: Valve seat 12: Adapter 13.16 2 guide holes 14.19.20: Air supply passage

Claims (1)

[Scope of Claims] An electromagnetic fuel injection valve that opens and closes a fuel injection valve hole formed in a valve body by reciprocating a rod-shaped movable valve due to the biasing force of a spring and the attractive force of an electromagnetic coil. The continuous valve seat and the movable valve tip that abuts the valve seat are both formed into a conical shape, and the valve seat and the movable valve are brought into contact with each other in a ring shape in a line contact state at the large diameter part of the cone, Furthermore, an adapter having a guide hole formed therein for regulating the spread of the fuel injected from the valve hole is attached to the tip of the valve body, and the adapter is provided with a guide hole that intersects with the guide hole to atomize the injected fuel into the guide hole. An air supply passage for supplying promoting air is formed, and the axial extension line position of the air supply passage is slightly shifted from the axis of the guide hole so that the air supply passage has an offset amount e. An electromagnetic fuel injection valve characterized in that a relationship between an offset amount e, a diameter d of the valve hole, and a diameter A of the air supply passage is set as e<(A+d)/2.