JPH09158785A - Fuel feeder for gas fuel internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mix gas fuel with intake air in a sufficiently uniform state by providing a gas fuel jet means for jetting gas fuel in a plurality of jet directions, in an intake passage, and jetting a relatively large quantity of gas fuel in the jet direction, most influenced by intake dynamic pressure, out of a plurality of jet directions. SOLUTION: In an internal combustion engine 1, intake ports 3 join at a surge tank 4 and are connected to an air cleaner by an intake pipe 4. A fuel injection valve 7 for injecting gas fuel is disposed at each intake port 3, and an adaptor 8 is fitted to a nozzle hole of the injection valve 7. The adaptor 8 is formed of two kinds of porous members with almost the same pore diameter, and the porous member 8a with a large number of pores per unit area is used for the bottom face, while the porous member 8b with a small number of pores per unit area is used for the side face. Gas fuel is thereby dispersed to the whole fitting position cross section of the fuel injection valve 7 of the intake port 3 so as to realize excellent uniform mixing of gas fuel and intake air.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fuel supply system for a gas fuel internal combustion engine.

[0002]

2. Description of the Related Art Internal combustion engines that use gas fuel are known. In such an internal combustion engine, various measures have been taken to sufficiently mix gas fuel with intake air.
For example, Japanese Unexamined Patent Publication No. 6-80825 discloses a fuel supply device that injects gas fuel from a fuel injection valve arranged in an intake passage toward an upstream side of intake air. This fuel supply device intends to uniformly mix with the intake air by colliding the gas fuel injected from the fuel injection valve with the intake air.

Further, in Japanese Unexamined Patent Publication No. 60-93165, a gas supply pipe is arranged substantially in the center of an intake passage, and a plurality of injection holes formed in the gas supply pipe radially inject gas fuel to supply fuel. A device is disclosed. This fuel supply device is intended to be uniformly mixed with intake air by ejecting gas fuel in a plurality of directions in the intake passage.

[0004]

[Patent Document 1] Japanese Patent Application Laid-Open No. 6-80825
In the fuel supply device disclosed in the publication, near the position where the gas fuel collides with the intake air, sufficient mixing with the intake air is realized, but the gas fuel cannot be made uniform over the entire cross section of the intake passage. Further, in the fuel supply device disclosed in Japanese Patent Application Laid-Open No. 60-93165, the amount of gas fuel ejected from the plurality of nozzles in the direction facing the intake air is greatly affected by the dynamic pressure of the intake air. Therefore, the amount of gas fuel ejected from other nozzles becomes considerably smaller. As a result, the gas fuel cannot be uniformly supplied to the entire cross section of the intake passage, and the uniform mixing of the gas fuel is still insufficient.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a fuel supply system for a gas fuel internal combustion engine which can mix gas fuel with intake air sufficiently in the intake passage.

[0006]

According to a first aspect of the present invention, there is provided a fuel supply system for a gas-fueled internal combustion engine, comprising gas-fuel jetting means for jetting gas fuel in a plurality of jetting directions in an intake passage, It is characterized in that a larger amount of gas fuel is ejected in the ejection direction which is most affected by the intake dynamic pressure among the plurality of ejection directions as compared with the other ejection directions.

The fuel supply system for this gas-fueled internal combustion engine is
Of the multiple jetting directions of the gas fuel jetting means, in the jetting direction that is most affected by the intake dynamic pressure, a large amount of gas fuel is jetted compared to the other jetting directions. Even if the dynamic pressure of intake air acts on the gas fuel jetting means at the time of jetting the gas fuel, the amount of gas fuel in the jetting direction which is greatly affected does not greatly fall below the amount of gas fuel in the other jetting directions.

According to a second aspect of the present invention, there is provided a fuel supply system for a gas fuel internal combustion engine, comprising: a gas fuel jetting means for jetting gas fuel into an intake passage; and a gas fuel jetting means inside the intake passage. And a deflecting member which is disposed at a facing position and which gas fuel jetted by the gas fuel jetting means collides with and bounces back in multiple directions.

The fuel supply system for this gas-fueled internal combustion engine is
The gas fuel jetted into the intake passage by the gas fuel jetting means collides with the deflecting member across the intake passage and bounces in multiple directions.

According to a third aspect of the present invention, there is provided a fuel supply system for a gas fuel internal combustion engine, comprising: a gas fuel jetting means for jetting gas fuel into an intake passage so as to have a velocity component opposed to an intake air flow; A deflecting member for deflecting a part of the gas fuel ejected by the gas fuel ejecting means in multiple directions immediately after ejection.

Further, in this fuel supply device for a gas-fueled internal combustion engine, the gas fuel is injected by the gas fuel injection means so as to have a velocity component facing the intake flow, and a part of the gas fuel is increased by the deflecting member immediately after the injection. Deflected in the direction.

[0012]

1 is a schematic sectional view of a gas-fueled internal combustion engine equipped with a fuel supply system according to a first embodiment. In the figure, 1 is an internal combustion engine that uses a gas fuel such as LPG. In the combustion chamber 1a of this internal combustion engine 1,
The exhaust port 2 is connected via the exhaust valve 1b, and the intake port 3 is connected via the intake valve 1c. The intake ports 3 of the respective cylinders merge in the surge tank 4 and are connected to an air cleaner (not shown) by a single intake pipe 6 in which a throttle valve 5 is arranged.

A fuel injection valve 7 for injecting gas fuel is arranged in each intake port 3. The fuel injection valve 7 itself injects the gas fuel in the axial direction thereof, and the injected fuel gas of the fuel injection valve 7 has a relatively large velocity component facing the intake air flow. The mounting angle θ is set.

As shown in FIG. 2, a cylindrical cap-shaped adapter 8 surrounding the injection port 7a of the fuel injection valve 7 is attached to the tip of the fuel injection valve 7. The adapter 8 is
It is formed by two kinds of porous members having substantially the same pore diameter. The bottom surface 8 of the adapter 8 facing the injection port 7a
The first porous member having a large number of holes per unit area is used for a, and the second porous member having a small number of holes per unit area is used for the side surface 8b of the adapter 8.

According to the fuel supply device thus constructed, the gas fuel injected from the fuel injection valve 7 is passed through the bottom surface 8a of the adapter 8 in the axial direction F1 of the fuel injection valve 7,
Via the side surface 8b, the plurality of radial directions F2 to Fn perpendicular to this direction F1 are advanced. At this time, there is an intake flow, and the largest intake dynamic pressure acts on the bottom surface 8a of the adapter 8, but the first porous member forming the bottom surface 8a has the side surface 8a.
Since the number of holes per unit area is larger than that of the second porous member forming b, the flow rate of the gas fuel ejected in the axial direction F1 is the same as that of the gas fuel ejected in the other directions F2 to Fn. The gas fuel does not fall below the range, and the gas fuel can be dispersed over the entire cross section of the mounting position of the fuel injection valve 7 of the intake port 3, and good uniform mixing of the gas fuel and the intake air can be realized.

FIG. 3 is a schematic sectional view of a gas fuel internal combustion engine to which the fuel supply system of the second embodiment is attached. Only the differences from the first embodiment will be described below. In the figure, the intake port 3 ′ is curved at the mounting position of the fuel injection valve 7. A deflecting protrusion 9 is formed on this curved portion of the intake port 3 ′ on the side facing the injection port 7 a of the fuel injection valve 7. This deflecting protrusion 9
As shown in FIG. 4, has a substantially semicircular cross-sectional shape in the direction perpendicular to the axis of the intake port 3 '.

According to the fuel supply device thus constructed, the gas fuel injected from the fuel injection valve 7 collides with the deflecting protrusion 9 and is deflected in multiple directions and bounces back, as shown in FIG. , Distributed throughout the curved section of the intake port 3 ',
Good uniform mixing with the intake air can be achieved. In particular, in the curved portion of the intake port 3 ', the intake air becomes a turbulent flow, so that this uniform mixing can be further improved.

FIG. 5 is a schematic sectional view of the tip of the fuel injection valve 7 corresponding to FIG. 2 showing the fuel supply system of the third embodiment. A deflection plate member 10 is attached to the tip of the fuel injection valve 7. The deflecting plate member 10 has a relatively large hole 10 at a position facing the injection port 7a of the fuel injection valve 7.
a, and the edge of the hole 10a is smoothly raised over the entire circumference. The fuel injection valve 7 to which such a deflecting plate member 10 is attached is the same as in the first embodiment.
Placed in

According to the fuel supply device thus constructed, the gas fuel injected from the fuel injection valve 7 passes through the hole 10a of the deflection plate member 10 as it is, as shown in FIG. That advances in the axial direction F1 of the injection valve 7,
The deflecting plate member 10 collides with the deflecting plate member 10 and travels in a plurality of radial directions F2 to Fn which are perpendicular to the direction F1. The largest intake dynamic pressure acts on the hole 10a of the deflecting plate member 10. However, since the hole 10a is formed relatively large, the flow rate of the gas fuel ejected in the axial direction F1 is different from that of the other. It does not fall below the flow rate of the gas fuel ejected in the directions F2 to Fn, and as in the first embodiment, good uniform mixing of the gas fuel and intake air can be realized.

FIG. 6 is a schematic sectional view of a gas fuel internal combustion engine to which the fuel supply system of the fourth embodiment is attached. FIG. 7 is an enlarged cross-sectional view near the tip of the fuel injection valve of FIG. Only the differences from the first embodiment will be described below. The fuel injection valve 7'in the present embodiment has a relatively long neck portion, and an injection port 7a 'is formed at the tip thereof so that the gas fuel is injected from the vicinity of the central axis of the intake port. An adapter 8'is attached so as to surround the injection port 7a 'of the fuel injection valve 7'. The adapter 8'has a cylindrical cap shape similar to that of the adapter 8 of the first embodiment. In this adapter 8 ',
The same first porous member having many holes per unit area is used for the bottom surface 8a 'of the adapter 8 facing the nozzle hole 7a', and the side surface 8b 'of the adapter 8 has the number of holes per unit area. A third porous member whose gradual change is used is used. Side surface 8b 'formed by this third porous member
Has a larger number of holes per unit area in the portion located on the intake upstream side.

According to the fuel supply device thus configured, the gas fuel injected from the fuel injection valve 7'is passed through the bottom surface 8a 'of the adapter 8'to the axial direction F1 of the fuel injection valve 7', Through the side surface 8b ′, the plurality of radial directions F2 to Fn perpendicular to this direction F1 proceed. At this time, there is an intake flow, and the largest intake dynamic pressure acts on the bottom surface 8a 'of the adapter 8'. However, the first porous member forming this bottom surface 8a 'has the third porous surface forming the side surface 8b'. Since the number of holes per unit area is larger than that of the quality member, the axial direction F
The flow rate of the gas fuel ejected in 1 does not fall below the flow rate of the gas fuel ejected in the other directions F2 to Fn. In addition, the side surface 8b ′ has a large number of holes per unit area because the third porous member increases the number of holes per unit area in a portion located on the intake upstream side, that is, a portion on which a large intake dynamic pressure acts. It is possible to inject the gas fuel with substantially the same flow rate in the plural directions F2 to Fn. Thereby,
It is possible to disperse the gas fuel over the entire cross section of the mounting position of the fuel injection valve 7'of the intake port 3, and it is possible to achieve good uniform mixing of the gas fuel and the intake air.

In the above-described second embodiment, the deflecting protrusion 9 is provided on the curved portion of the intake port 3 ', and the turbulent flow of intake air generated here is used for mixing gas fuel and intake air. However, even for laminar intake air, the deflecting protrusion 9
In order to relatively uniformly mix the gas fuel deflected and rebounded in a plurality of directions by the above, it is possible to provide the deflection protrusion 9 in the straight portion of the intake port 3 '. Further, the deflecting protrusion 9 may be one that deflects the gas fuel that collides with it in multiple directions and bounces it back, and as described above, has a substantially semicircular cross-sectional shape in the direction perpendicular to the axis of the intake port 3 '. The shape is not limited to that described above, and may be a polygonal pyramid such as a quadrangular pyramid or a hexagonal pyramid in consideration of the collision direction of the gas fuel.

In the fourth embodiment described above, the intake dynamic pressure hardly acts on the portion of the side surface of the adapter 8'which is located on the most intake downstream side even if the intake amount increases. Therefore, due to the change in the intake air amount, not only the intake dynamic pressure acting on each part of the adapter 8 ', but also the size ratio, changes. Further, the larger the mounting angle θ of the fuel injection valve 7 ′, the greater the intake dynamic pressure acting on the bottom surface 8a ′ of the adapter 8 ′ even with the same intake amount. As a result, the flow rate of the gas fuel ejected from the adapter 8 ′ in the respective directions F1, F2 to Fn cannot be always equalized for each intake air amount, and the adapter 8 ′ for the most frequent intake air amount. The number of holes per unit area of each porous member forming the adapter 8 ′ is selected in consideration of the mounting angle θ of the fuel injection valve 7 ′ so that the flow rates of the gas fuel ejected from the respective parts become equal. .

In addition, the intake amount used when selecting the number of holes per unit area of each porous member may be the maximum intake amount of the internal combustion engine. In this case, with a normal intake air amount, the flow rate of the jetted gas fuel increases as the portion of the adapter 8'on which a large intake dynamic pressure acts. That is, the flow rate of the gas fuel ejected from each part of the adapter 8 ′ increases as the velocity component facing the intake flow increases.

When the adapter 8'is configured as described above, particularly in the axial direction F1 of the fuel injection valve 7'and in the direction F2 perpendicular to this axial direction F1 and on the central longitudinal section of the intake port 3, a large amount of gas fuel is produced. Erupted into. This large amount of gas fuel collides with the intake flow and is dispersed. Further, the gas fuel is also ejected from the adapter 8 ′ in a plurality of radial directions perpendicular to the axial direction F1, and the gas fuel is also provided to a portion where the gas fuel dispersed due to the collision with the intake air does not reach. Therefore, even in this case, the fuel injection valve 7 of the intake port 3
It is possible to disperse the gas fuel over the entire cross section of the mounting position, and it is possible to achieve good uniform mixing of the gas fuel and the intake air.

In the first embodiment, the number of holes per unit area of the second porous member forming the side surface of the adapter 8 is the same, but the number of holes per unit area of the first porous member forming the bottom surface is the same. The above ideas can be applied in relation to. Further, in the third embodiment, when determining the diameter of the hole 9a in the deflecting plate member 9 and the shape such as a ridge around the hole 9a, the flow rate of the gas fuel advancing in the axial direction F1 of the fuel injection valve 7 and The relationship is considered with respect to the flow rate of the gas fuel which is perpendicular to the direction F1 and progresses in a plurality of radial directions F2 to Fn, and the above-described idea can be applied to this relationship. In the first and fourth embodiments, the adapter 8,
Each of the porous members forming 8'has the same pore diameter and changes the flow rate of the gas fuel ejected in each direction by the number of pores per unit area, but of course, the porous members having different pore diameters. It is also possible to change the flow rate using.

[0027]

As described above, according to the fuel supply device for a gas fuel internal combustion engine of the present invention as set forth in claim 1, the gas fuel jetting means jets the gas fuel in a plurality of jetting directions in the intake passage. Of these multiple jetting directions, a larger amount of gas fuel is jetted in the jetting direction that is most affected by the intake dynamic pressure than in the other jetting directions. Even if the intake dynamic pressure acts on the gas fuel jetting means at the time of jetting the gas fuel, the amount of gas fuel in the jetting direction which is greatly affected does not greatly fall below the amount of gas fuel in the other jetting directions. It is possible to disperse the gas fuel in the entire vicinity of the cross section perpendicular to the axis of the intake passage arranged, and it is possible to mix the gas fuel and the intake air in a good and uniform manner.

According to the fuel supply device for a gas fuel internal combustion engine according to the present invention, the gas fuel jetting means for jetting the gas fuel into the intake passage and the gas fuel jetting means in the intake passage are provided. The gas fuel jetted by the gas fuel jetting means into the intake passage is provided with a deflecting member which is arranged at a facing position and collides with the gas fuel jetted by the gas fuel jetting means and bounces back in multiple directions. It collides with the deflecting member across the passage, bounces back in multiple directions, and the gas fuel can be dispersed in the entire vicinity of the cross section perpendicular to the axis of the intake passage in which the gas fuel jetting means is arranged. Good uniform mixing can be achieved.

According to the fuel supply device for a gas fuel internal combustion engine of the present invention as defined in claim 3, the gas fuel jetting means for jetting the gas fuel into the intake passage so as to have a velocity component opposed to the intake flow. And a deflecting member that deflects a part of the gas fuel ejected by the gas fuel ejection means in multiple directions immediately after ejection, so that the gas fuel ejection means has a velocity component facing the intake flow The fuel is injected, and a part of the fuel is deflected in multiple directions immediately after being ejected by the deflecting member, so that the gas fuel can be dispersed in the entire vicinity of the cross section perpendicular to the axis of the intake passage in which the gas fuel ejecting means is arranged, The gas fuel and the intake air can be mixed satisfactorily and uniformly.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a gas fuel internal combustion engine to which a fuel supply device according to a first embodiment is attached.

FIG. 2 is a cross-sectional view in the vicinity of a tip portion of the fuel injection valve of FIG.

FIG. 3 is a schematic cross-sectional view of a gas-fueled internal combustion engine to which the fuel supply device of the second embodiment is attached.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is a sectional view in the vicinity of a tip portion of a fuel injection valve of a fuel supply device according to a third embodiment.

FIG. 6 is a schematic cross-sectional view of a gas fuel internal combustion engine to which a fuel supply device of a fourth embodiment is attached.

7 is a cross-sectional view in the vicinity of the tip of the fuel injection valve of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Gas fuel internal combustion engine 3, 3 '... Intake port 7, 7' ... Fuel injection valve 8, 8 '... Adapter 9 ... Deflection protrusion 10 ... Deflection plate member

Claims (3)

[Claims] 1. A gas fuel jetting means for jetting a gas fuel in a plurality of jetting directions in an intake passage, wherein the jetting direction which is most affected by the intake dynamic pressure among the plurality of jetting directions is A fuel supply device for a gas-fueled internal combustion engine, characterized in that a large amount of gas fuel is ejected as compared with the ejection direction of. 2. A gas fuel jetting means for jetting a gas fuel into the intake passage and a gas fuel jetted by the gas fuel jetting means arranged at a position facing the gas fuel jetting means in the intake passage collide with each other. And a deflecting member that rebounds in multiple directions, and a fuel supply device for a gas fuel internal combustion engine. 3. A gas fuel jetting means for jetting a gas fuel into an intake passage so as to have a velocity component opposed to an intake air flow, and a portion of the gas fuel jetted by the gas fuel jetting means is immediately after being jetted. And a deflecting member that deflects in a direction, and a fuel supply device for a gas fuel internal combustion engine.