JPS5847250Y2 - Diesel engine fuel injection valve device - Google Patents

Description

[Detailed description of the invention] This invention relates to a fuel injection valve device in the combustion chamber of a direct injection diesel engine. Conventionally, the fuel injection valve in the combustion chamber of a direct injection diesel engine has a cylindrical nozzle body at the lower end. Then, the fuel was injected from this nozzle.

In such a case, ignition occurs near the nozzle hole of the nozzle body,
This increases the temperature near the nozzle hole, promotes evaporation of the subsequent fuel spray, reduces the penetration rate, reduces the proportion of fuel that reaches the peripheral wall of the combustion chamber, and worsens the mixing condition of fuel and air. It is difficult to achieve complete combustion, which causes a reduction in output or the generation of smoke.

This phenomenon is particularly noticeable when the injection timing is delayed.

In view of these circumstances, the second plan is to maintain an appropriate reach so that the spray injected from the nozzle hole of the fuel injection valve does not ignite near the nozzle hole, and to distribute the spray as uniformly as possible throughout the combustion chamber. In the combustion chamber of a direct injection diesel engine, a plurality of protective cylinders extending in radial directions are connected to the lower end of the cylindrical mounting part, and the axis of the protective cylinders is aligned with the cylinder head. This is a fuel injection valve device for a diesel engine, characterized in that an ignition control body is attached to the tip of the nozzle, the ignition control body being aligned with the nozzle hole axis of the nozzle of the fuel injection valve added to the inner surface of the fuel injection valve.

An embodiment of the present device will be described with reference to FIGS. 1 and 2. In the combustion chamber 5 of a direct injection diesel engine, which is formed by the inner surface 2 of the cylinder head 1 and the recess 4 formed in the top of the piston 3, An ignition control body 8 is attached to the tip of a nozzle 7 of a fuel injection valve 6 attached to an inner surface 2 of a cylinder head 1.

This ignition control body 8 has a plurality of protective cylinder parts 12, 12.12.
2, a covering part 13 having a cover part 13 having a
．． The base of the upper half 12a of 12, 12.12 is integral with the cylindrical attachment part 11, and the base of the lower half 12b is integral with the chevron-shaped enlarged part 14 formed in the center of the bottom surface, and each protective cylinder 12
When viewed from the bottom surface, they extend in a radial direction from a cross shape centering on the chevron-shaped enlarged portion 14, and have the same protruding length.

In addition, the inner peripheral surface 12c of the protective cylinder part 12 is expanded in diameter toward the discharge end, and the inner peripheral axis is aligned with the nozzle hole 15 of the nozzle 7.
The axis 16 coincides with the inner peripheral axis of the nozzle 7, and the dish-shaped inner surface 17 of the chevron-shaped enlarged portion 14 is formed so as to maintain an interval along the surface of the front end 7a of the nozzle 7.

In this case, the protrusion length of the protective cylinder part 12, that is, the distance between the center 01 of the front end 7a of the nozzle 7 and the tip end surface 12d of the protective cylinder part 12 on the axis 16 is Ll, and the axis 16 and the piston 3 The distance between the intersection C of the four faces of the recess and the center O1 is L2
In this case, the distance L1 is selected so that Ll/L2 has an optimal value in consideration of the shape of the combustion chamber, the fuel injection state, etc.

Since the present device is configured as described above, the fuel injected from the nozzle hole 15 of the nozzle 1 of the fuel injection valve 6 passes into the combustion chamber 5 through the protective cylinder part 12 communicating with the nozzle hole 15, Ignition occurs at an ignition point A slightly separated from the tip surface 12d of the 12.

In this way, the atomized fuel passes through the protective tube 12 corresponding to each nozzle hole 15 and is released into the combustion chamber 5 and ignites, so that it ignites near the nozzle hole so that it can be ignited in a conventional fuel injection valve. The atomized fuel and air are well mixed by the vortex port in the combustion chamber 5, and the combustion is as uniform as possible within the combustion chamber 5. be able to.

FIG. 3 shows a modification of the ignition control body 8, in which the ignition control body 18 has window holes 20 penetrating through both side walls of the protective cylinder portion 19, and the bottom wall of the bulge portion 21. Opening 22 in the center
It is designed to prevent the vortex effect from diminishing due to the protective cylinder part 19, and the window hole 20 has a secondary turbulence effect.

The ignition control body 8 of the embodiment shown in FIGS. 1 and 2, and the ignition control body 8 shown in FIG. 3! F) A comparative experiment was conducted using the ignition control body 18 as an example, and the smoke state associated with Ll/L2 was as shown in the diagram of FIG.

This project prevents ignition in the vicinity of the fuel injector in the combustion chamber of a direct injection diesel engine, prevents a drop in penetration due to evaporation of the spray, and increases the reach of the spray without causing cracks, thereby increasing the reach of the entire combustion chamber. Since fuel and air are well mixed and combusted over a period of time, the engine's output performance and smoke performance can be improved, and other practical effects are outstanding.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the main part showing an embodiment of the proposed device, Fig. 2 is a bottom view of the part corresponding to the line ■-■ in Fig. 1, and Fig. 3 is a half-part vertical sectional view showing the main part of another embodiment. FIG. 4 is a comparison diagram of the two embodiments. 1...Cylinder head, 2...Inner surface,
3...Piston, 4...Recess, 5...
... Confucian fire chamber, 6... Confucian fire injection valve, 1...
・Nozzle, 8...Ignition control body, 11...
・Cylindrical hooked part, 12... Protective cylinder part, 13...
... Cover, 14... Yamagata Ampulla, 15...
...Nozzle hole, 16...Axis, A...Blow point, mouth...
...A whirlpool.

Claims (1)

[Scope of utility model registration request] In the combustion chamber of a direct injection diesel engine, a plurality of protective cylindrical parts extending in radial directions are installed in series at the lower end of the cylindrical mounting part,
A fuel injection valve for a diesel engine, characterized in that an ignition control body is attached to the tip of the nozzle, the axis of the protective cylinder portion being aligned with the axis of the nozzle of the nozzle of the fuel injection valve attached to the inner surface of the cylinder head. Device.