JPS61247865A - Fuel injection type engine - Google Patents

Abstract

PURPOSE:To enhance the combustibility of an engine to aim at enhancing the fuel economy of the same having a fuel injection valve disposed in the merging section of two intake ports, by setting the bore diameter of one of two intake ports which is near to an ignition plug, to a large value. CONSTITUTION:Two intake ports 2, 3 parted by partition plate 13 and one exhaust port 4 are opened to an engine cylinder 1. A fuel injection valve 6 is disposed in the upstream side merging section of two intake ports 2, 3, having two jet ports directed to these two ports 2, 3. Further, ignition plug 7 is biased toward the intake-air port 2 side. In this arrangement, one of two jet ports of the fuel injection valve 6 having a larger bore diameter is directed to the intake port 2 near to the ignition plug 7 while another one having a smaller bore diameter is directed to the intake port 3. With this arrangement, a rich mixture may be created in the vicinity of the ignition plug 7, thereby it is possible to ensure a satisfactory ignition ability even if the air-fuel ratio is set to be leans as a whole.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application 1] The present invention relates to a fuel injection engine, and particularly to an engine in which two intake boats are merged on an upstream side and a fuel injection valve is provided at the merge portion.

[Prior Art 1] As mentioned above, a fuel injection engine in which two intake boats are joined upstream and a fuel shoulder injection valve is provided at the joining part is well known (for example, in the 1980- 1784
(See Publication No. 54).

As mentioned above, when two intake boats are provided, an advantage is obtained that the filling amount can be increased. However, when fuel is injected toward the two intake boats from the fuel injection valve located at the confluence, the injected mist fuel collides with the partition wall separating the two intake boats and collects in droplets. There is still room for improvement in the vaporization and atomization performance of the fuel, such as the flow flowing along the partition wall.

The present applicant has applied for patent application No. 59-77236 (Showa 5
(Application filed on April 17, 2009) discloses a fuel injection system in which a fuel injection valve having two nozzles is provided and the fuel injected from each nozzle is directed to each intake boat without colliding with the bulkheads of the two intake boats. The formula engine has already been proposed.

According to the prior invention of the present applicant, the vaporization and atomization characteristics of the injected fuel can be fundamentally improved.

However, in an engine equipped with such a fuel injection valve having two nozzles, it is desired to further improve combustibility and improve fuel efficiency.

[Objective of the Invention 1 The object of the present invention is to optimize the injection characteristics between the nozzles in relation to the installation position of the spark plug when two nozzles are provided in a fuel injection valve disposed at the confluence of two intake boats. The aim is to improve combustibility and, by extension, fuel efficiency.

[Configuration 1 of the Invention For this reason, the present invention sets the nozzle diameters of the two nozzles provided in the fuel injection valve disposed at the merging part where two intake boats are joined to be different in size, while the spark plug is The fuel injection valve is arranged so as to be biased toward one intake boat, and the fuel injection valve is arranged so that the nozzle with a large diameter is directed toward the intake boat near the ignition plug.

[Effect of the invention 1] According to the present invention, fuel can be injected directly to each intake boat, and the injected fuel can be concentrated around the spark plug to enrich the mixture. By improving the ignitability of air, it is possible to improve combustibility and fuel efficiency.

[Example 1 Examples of the present invention will be specifically described below.

As shown in FIG. 1 for one cylinder of the engine, the cylinder 1 has two intake boats 2.3 and one exhaust boat 4 opened therein. These two intake boats 2 and 3 are merged into one on the upstream side, and the merge part 5 has a fuel injection valve 6 having two injection ports.
is arranged so that it points toward the two intake bows) 2.3. Further, the spark plug 7 is arranged to be biased toward one side of the intake boat 2.

As shown in FIG. 2, the fuel injection valve 6 has two injection ports 9 and 10 formed at the tip of the nozzle tip 8. As shown in FIG.

The nozzle diameters of these two nozzle holes 9 and 10 are set to be different in size, and the nozzle nozzle 9 with a large nozzle diameter is directed toward the intake boat 2 near the ignition plug 7, while the nozzle nozzle 10 with a small nozzle diameter is directed to the intake boat 3 located away from the spark plug 7.

Although not specifically shown in the drawings, when the built-in electromagnetic coil is excited, this fuel injection valve 6 causes the needle valve 11 to move backward, and as the needle valve 11 moves back, each injection port 9
, 10 has a well-known structure in which fuel is injected from them.

Further, as shown in FIG. 3, the spout ports 9' and 10'' may be provided in a cap body 12 attached to the tip of the nozzle tip 8'.

As described above, when the fuel injection valve 6 having two nozzles is arranged, as exemplarily shown in FIG.
A large amount of fuel is supplied to the intake boat 2 near the spark plug 7 from the nozzle 9 with a large nozzle diameter, and a small amount of fuel is supplied from the nozzle 10 with a small nozzle diameter to the intake boat 3 far from the spark plug 7. This means that the fuel will be injected and supplied without colliding with the partition wall 13 that separates the parts 2 and 3.

As a result, the air-fuel mixture around the spark plug 7 becomes rich.
The air-fuel mixture around the spark plug 7 is ignited well by the spark ignition of the spark plug 7, and combustion proceeds throughout the combustion chamber with this rich air-fuel mixture as the nucleus.

The ratio of fuel supplied from the two nozzles 9.10 (9', 10'') is preferably set as follows, for example.

Now, in the 0□ feedback control region where the air-fuel mixture is controlled to the stoichiometric air-fuel ratio (A/F = 14.7), the air-fuel ratio near the spark plug 7 is set to approximately 13.0, and the air-fuel ratio on the other side of the intake boat 3 is set to approximately 13.0. It should be about 16.4.

In addition, in the area where 0□ feedback control is not performed,
The air-fuel ratio is set to 14.7 on the spark plug 7 side and 25.3 on the other side, and the entire engine can be operated at an air-fuel ratio of 20.

As described above, with the configuration of the present invention, a rich air-fuel mixture can be generated near the spark plug 7, so even if the overall air-fuel ratio is set lean, ignitability is ensured well and combustibility is inhibited. Of course, the air-fuel ratio setting examples shown in the above embodiments are merely examples, and the present invention is not limited thereto.

[Brief explanation of the drawing]

FIG. 1 is an explanatory sectional view of one cylinder of an engine according to the present invention, and FIGS. 2 and 3 are sectional views of the tip of a fuel injection valve, respectively. 2.3...Intake boat, 7...Spark plug,
6...Fuel injection valve, (9, 10), (9", 10')...Nozzle port.

Claims (1)

[Claims] (1) In a fuel injection engine in which two intake ports are joined on the upstream side and a fuel injection valve is provided at the joining part, the spark plug is placed biased toward one intake port, and the fuel injection valve A fuel injection type engine characterized in that two nozzles are provided for injecting fuel toward each port, and the diameter of the nozzle on the intake port side closer to the ignition plug is set larger than the diameter of the other nozzle.