JPH05180049A - Fuel supply device in four-valve type internal combustion engine - Google Patents

Abstract

PURPOSE:To attain sure ignition and combustion of an intake mixture and cleaning of exhaust gas, in a 4-valve type internal combustion engine formed by a providing two intake valves and two exhaust valves relating to a single combustion chamber. CONSTITUTION:The inside of a combustion chamber 5 is divided into the first combustion chamber 5a of containing one intake valve 11 and one exhaust valve 13 and the second combustion chamber 5b of containing the other intake valve 12 and the other exhaust valve 14, with a spark plug 22 bordering. Fuel injection by the first fuel injection valve 23 relating to the first combustion chamber 5a and fuel injection by the second fuel injection valve 24 relating to the second combustion chamber 5b are alternately performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is of a so-called four-valve type in which two intake valves and two exhaust valves are provided for one combustion chamber provided with an ignition means such as a spark plug at a substantially center thereof. The present invention relates to a fuel supply device for sucking fuel into a combustion chamber of an internal combustion engine.

[0002]

2. Description of the Related Art In a four-valve internal combustion engine of this kind, one combustion chamber having an ignition plug is provided with two intake ports each having an intake valve and an exhaust port also having an exhaust valve. A first chamber including one intake port and one exhaust port with the ignition plug as a boundary, and a second chamber including the other intake port and the other exhaust port, while being disposed in a facing portion. The prior art is disclosed in Japanese Patent Publication No. 49-23848 and Japanese Utility Model Publication No. 57-2262.
No. 8 publication and the like.

[0003]

The four-valve internal combustion engine according to this prior art is configured as described above, so that the intake air-fuel mixture sucked from the two intake ports has a longitudinal loop. Although a vortex flow (tumble flow) is applied to promote the ignition and combustion of the intake air-fuel mixture, the air-fuel mixture having substantially the same air-fuel ratio is sucked from both the intake ports. If the air-fuel ratio of the intake air-fuel mixture is set to lean, not only will ignition and combustion of the intake air-fuel mixture become unstable, but drivability will be reduced, and unburned components such as hydrocarbons in the exhaust gas will increase. When the air-fuel ratio of the intake air-fuel mixture is set to be rich, the ignition / combustibility of the intake air-fuel mixture can be improved, but the combustion temperature rises and the amount of nitrogen oxides in the exhaust gas increases. There has been a problem to say.

The present invention solves the above problems by utilizing the characteristics of the four-valve internal combustion engine described above to perform stratified intake of a lean air-fuel mixture and a rich air-fuel mixture. This is a technical issue.

[0005]

In order to achieve this technical object, a first aspect of the present invention is directed to one combustion chamber provided with an ignition means such as a spark plug, and two intake ports each provided with an intake valve.
Similarly, two exhaust ports each provided with an exhaust valve are arranged at opposite positions, and the combustion chamber includes one intake port with the ignition means as a boundary and one exhaust port facing the intake port. In a four-valve internal combustion engine including one combustion chamber and a second combustion chamber including the other intake port and the other exhaust port facing the other intake port, a first fuel injection valve for the first combustion chamber, A fuel injection valve for the second combustion chamber, and fuel injection by the first fuel injection valve;
The fuel injection by the second fuel injection valve is alternately performed.

A second aspect of the present invention is such that one combustion chamber provided with ignition means such as a spark plug, two intake ports each provided with an intake valve, and two exhaust ports also provided with each exhaust valve. On the other hand, while the combustion chamber,
A first combustion chamber that includes one intake port and one exhaust port that faces the intake port, and a second combustion chamber that includes the other intake port and the other exhaust port that faces the intake port. A four-valve internal combustion engine comprising: a first fuel injection valve for the first combustion chamber and a fuel injection valve for the second combustion chamber, and a fuel injection amount by the first fuel injection valve; The fuel injection amount by the fuel injection valve is configured to be alternately increased and decreased.

[0007]

[Operation] In this type of four-valve internal combustion engine, during the intake stroke due to the downward movement of the piston, each exhaust gas is introduced into each of the air-fuel mixtures flowing into the first combustion chamber and the second combustion chamber from both intake ports. A longitudinal vortex flow (tumble flow) can be applied in the longitudinal direction toward the port, and the intake air-fuel mixture of the two vortex flows (tumble flow) is mutually compressed in the compression stroke accompanying the upward movement of the piston. Compressed while mixing.

Therefore, as described above, the first fuel injection valve for the first combustion chamber and the fuel injection valve for the second combustion chamber are provided, and the fuel injection by the first fuel injection valve and the second fuel injection valve are performed. By alternately performing the fuel injection by the fuel injection valve, when the fuel is injected and supplied by the first fuel injection valve, the air-fuel ratio of the intake air-fuel mixture on the first combustion chamber side becomes rich. , The air-fuel ratio of the intake air-fuel mixture on the second combustion chamber side becomes lean, and when the fuel is injected and supplied by the second fuel injection valve, the air-fuel ratio of the intake air-fuel mixture on the second combustion chamber side becomes rich. On the other hand, since the air-fuel ratio of the intake air-fuel mixture on the first combustion chamber side becomes lean, the air-fuel ratio of the intake air-fuel mixture on the first combustion chamber side and the air-fuel ratio of the intake air-fuel mixture on the second combustion chamber side become And can be a rich lean alternately, it is possible to achieve a stratified charge.

Further, in the stratified intake air, the fuel injection amount by the first fuel injection valve and the fuel injection amount by the second fuel injection valve are alternately increased and decreased as described in "Claim 2". It can also be achieved by configuring. By the way, in the case of performing stratified intake, it is necessary that only the intake air-fuel mixture on one combustion chamber side of the first and second combustion chambers has a rich air-fuel ratio at all times on the other combustion chamber side with respect to the inner wall surface thereof. Adhesion of carbon etc. will increase.

On the other hand, in the case of the present invention, combustion at a high temperature due to a rich air-fuel ratio is alternately performed in both the first combustion chamber and the second combustion chamber, so that it is similar to the inner wall surface of the combustion chamber or the like. Adhesion of carbon or the like can be reliably reduced.

[0011]

Therefore, according to the present invention, the so-called stratified intake can simultaneously achieve reliable ignition / combustibility of the intake air-fuel mixture and clean exhaust gas, and the inner wall surface of the combustion chamber or the like. It has the effect of reliably reducing the adhesion of carbon and the like to the.

In particular, in the case of the construction as in "Claim 2", in addition to the above-mentioned effects, the fuel is constantly supplied from both combustion injection valves, so that carbon is supplied to both fuel injection valves. This has the effect of reliably reducing the adherence of the like.

[0013]

Embodiments of the present invention will now be described with reference to the drawings. In the drawing, reference numeral 1 denotes a cylinder block having a cylinder bore 2, reference numeral 3 denotes a cylinder head fastened to the upper surface of the cylinder block 1, and a reciprocating piston 4 is provided in the cylinder bore 2 of the cylinder block 1. And the cylinder head 3 is inserted.
A combustion chamber 5 is formed on the lower surface of the recess.

Reference numerals 6 and 7 denote two intake ports that open to the combustion chamber 5, and reference numerals 8 and 9 similarly denote the combustion chamber 5.
And two exhaust ports 8 and 9 are shown in FIG. 2, and these intake ports 6 and 7 and exhaust ports 8 and 9 pass through substantially the center of the combustion chamber 5 and the crankshaft ( (Not shown), with the longitudinal center line 10 extending substantially parallel to the left and right sides being sandwiched, the left and right regions are distributed and arranged.
Further, intake valves 11 and 12 are provided at the openings of the intake ports 6 and 7 into the combustion chamber 5, and exhaust valves 13 and 14 are provided at the openings of the exhaust ports 8 and 9 into the combustion chamber 5. Are provided respectively. Further, intake pipes 15 and 16 for guiding air from an air cleaner (not shown) to the intake ports 6 and 7 are connected to the openings of the intake ports 6 and 7 to the side surface 3a of the cylinder head 3. Has been done.

On the other hand, inside the combustion chamber 5,
A raised portion 17 that divides the inside into a first combustion chamber 5a in which one intake port 6 and one exhaust port 8 open and a second combustion chamber 5b in which the other intake port 7 and the other exhaust port 9 open While the raised portion 17 is integrally formed so as to extend in a direction substantially perpendicular to the longitudinal centerline 10, the combustion chamber 5 is formed on the lower surface of the cylinder head 3 at both end portions of the raised portion 17. The squish areas 18 and 19 projecting inward are provided, and the left and right side surfaces of the raised portion 17 and the side surfaces of the squish areas 18 and 19 are formed into inclined surfaces 20 and 21. Further, in the cylinder head 3, the spark plug 22 is seen so that the electrode portion 22a of the spark plug 22 can be seen in both the first combustion chamber 5a and the second combustion chamber 5b at the location of the raised portion 17. Screw on.

The intake pipe 1 to the first combustion chamber 5a
5, the first fuel injection valve 23 is configured to inject and supply fuel during the intake stroke, and the intake pipe 16 to the second combustion chamber 5b is configured to inject and supply fuel during the intake stroke. A second fuel injection valve 24 is provided to inject and supply fuel only from the first fuel injection valve 23 during the first intake stroke, and to inject fuel only from the second fuel injection valve 24 during the next intake stroke. As described above, the fuel injection by the first fuel injection valve 23 and the fuel injection by the second fuel injection valve 24 are alternately performed.

In the case of this embodiment, the first fuel injection valve 23 and the second fuel injection valve 24 inject fuel from the fuel injection valves 23, 24 with arrows 23a, 23b and 24a, 24b. As shown in (2), it is mainly configured to be performed in two directions, that is, a direction toward the spark plug 22 and a direction away from the spark plug 22.
Further, exhaust gas recirculation passages 25 and 26 are connected to the intake pipes 15 and 16, respectively.

In this structure, in the intake stroke due to the downward movement of the piston 4, each exhaust port is provided to each of the air-fuel mixtures flowing from the intake ports 6 and 7 into the first combustion chamber 5a and the second combustion chamber 5b. As shown by the arrow A in FIG. 1, it is possible to apply a longitudinal loop-shaped vortex flow (tumble flow) toward 8 and 9. Then, the intake air-fuel mixture of the two loop vortex flows (tumble flow) is simultaneously compressed in the compression stroke accompanying the upward movement of the piston 4.

Therefore, as described above, the first fuel injection valve 23 for the first combustion chamber 5a and the second combustion chamber 5
By providing a fuel injection valve 24 for b, the fuel injection by the first fuel injection valve 23 and the fuel injection by the second fuel injection valve 24 are alternately performed,
When fuel is injected and supplied by the first fuel injection valve 23, the air-fuel ratio of the intake air-fuel mixture on the side of the first combustion chamber 5a becomes rich, while the air-fuel ratio of the intake air-fuel mixture on the side of the second combustion chamber 5b becomes lean. When the fuel is injected and supplied by the second fuel injection valve 24, the air-fuel ratio of the intake air-fuel mixture on the second combustion chamber 5b side becomes rich, while the intake-air mixture on the first combustion chamber 5a side becomes rich. Therefore, the air-fuel ratio of the intake air-fuel mixture on the side of the first combustion chamber 5a and the air-fuel ratio of the intake air-fuel mixture on the side of the second combustion chamber 5b can be alternately made rich and lean. It is possible to achieve stratified intake.

In the above-described embodiment, the case where the stratified intake is achieved by alternately arranging the fuel injection by the first fuel injection valve 23 and the fuel injection by the second fuel injection valve 24 has been shown. In this stratified intake, the fuel injection amount from the first fuel injection valve 23 is increased and the fuel injection amount from the second fuel injection valve 24 is decreased during the first intake stroke,
In the next intake stroke, the fuel injection amount from the second fuel injection valve 24 is increased while the fuel injection amount from the first fuel injection valve 23 is decreased. This can also be achieved by alternately increasing and decreasing the fuel injection amount of the second fuel injection valve 24.

The two fuel injection valves 23 and 24 may be provided directly to the first combustion chamber 5a and the second combustion chamber 5b, and instead of the spark plug 22 in the above embodiment. For example, as described in Japanese Utility Model Publication No. 54-19441 and Japanese Utility Model Publication No. 54-38401, the sub chamber cup surrounding the ignition plug is provided with a plurality of ejection holes. It goes without saying that other ignition means may be applied.

[Brief description of drawings]

1 is a vertical sectional front view showing an embodiment of the present invention, which is indicated by I in FIG.
FIG. 3 is a sectional view taken along line I.

FIG. 2 is a bottom view taken along the line II-II in FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

[Explanation of symbols]

 1 Cylinder Block 2 Cylinder Bore 3 Cylinder Head 4 Piston 5 Combustion Chamber 5a First Combustion Chamber 5b Second Combustion Chamber 6,7 Intake Port 8,9 Exhaust Port 11,12 Intake Valve 13,14 Exhaust Valve 15,16 Intake Pipe 17 Raised Part 22 Spark plug 23 First fuel injection valve 24 Second fuel injection valve

Claims (2)

[Claims] 1. A combustion chamber provided with ignition means such as a spark plug, and two intake ports each provided with an intake valve, and two exhaust ports also provided with respective exhaust valves are provided at positions facing each other. On the other hand, a first combustion chamber including one intake port and one exhaust port facing the intake port, and the other intake port and the other exhaust port opposite to the intake chamber A four-valve internal combustion engine including a second combustion chamber including a first combustion chamber
A fuel injection valve and a fuel injection valve for the second combustion chamber are provided, and the fuel injection by the first fuel injection valve and the second fuel injection valve are performed.
A fuel supply device for a four-valve internal combustion engine, characterized in that the fuel injection is performed alternately by the fuel injection valve. 2. A combustion chamber provided with ignition means such as a spark plug, and two intake ports each provided with an intake valve, and two exhaust ports also provided with respective exhaust valves are provided at positions facing each other. On the other hand, a first combustion chamber including one intake port and one exhaust port facing the intake port, and the other intake port and the other exhaust port opposite to the intake chamber A four-valve internal combustion engine including a second combustion chamber including a first combustion chamber
A fuel injection valve and a fuel injection valve for the second combustion chamber are provided, and the fuel injection amount by the first fuel injection valve and the fuel injection amount by the second fuel injection valve are alternately increased and decreased. A fuel supply device for a four-valve internal combustion engine characterized by the above.