JPS59101532A - Three valve type internal-combustion engine - Google Patents

Abstract

PURPOSE:To produce swirls in an air-fuel mixture and to promote uniformization in the air-fuel ratio as well as to accelerate the starting of combustion and to aim at a reduction in fuel consumption, by installing a swirl guide projectingly between two suction valve ports in the ceiling surface of a combustion chamber. CONSTITUTION:In a suction stroke, first a first suction valve 18 opens, then an air-fuel mixture entered into a combustion chamber 6 causes swirls in an arrow direction by a guide surface 8a of a swirl guide 8. Next, a second suction valve 182 opens, while the air-fuel mixture flowing into the combustion chamber 6 also causes swirls in the same arrow direction after being guided by a guide surface 8b of the swirl guide surface 8 and a side face 11b of a squish part 11 and builds up the swirl while joining the flowing mixture from a suction valve port 9, in advance, thus the air-fuel ratio of the mixture is uniformized. An ignition point by a flame shot up from each of torch nozzles 12 and 12 is in close vicinity to a nearby point (a) of the first suction valve 181. Therefore, the air-fuel mixture ignited in the combustion chamber 6 is immediately carried to the vicinity of an exhaust valve 19, which comes into a state of being high temperature affected by exhaust heat already, by swirls in the same direction so that the starting of combustion is accelerated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a three-valve internal combustion engine having two intake valve ports and one exhaust valve port opening into a combustion chamber.

In this type of internal combustion engine, it is generally possible to obtain a sufficiently large overall effective area of the intake valve port on the ceiling surface of the narrow combustion chamber, so that the filling dynamic strain can be reduced.
Since the area of each intake valve port is relatively small, the diameter of the intake valve that opens and closes it is reduced to reduce its inertial weight, and the valley intake valve follows the valve mechanism during high-speed engine operation. There is a certain point where the performance can be improved and excellent high-speed output performance can be achieved.

In the present invention, when such an engine is applied to a torch-ignited internal combustion engine equipped with a torch nozzle, a swirl guide is provided on the ceiling of the combustion chamber so as to intervene between two intake valves, thereby improving the mixing efficiency. This creates a swirl when air flows into the combustion chamber, thereby equalizing the air-fuel ratio of the air-fuel mixture and promoting the start-up of combustion, thereby promoting the above-mentioned advantages and reducing fuel consumption. The purpose is to

Hereinafter, one embodiment of the present invention will be explained with reference to the drawings.
Ru. The illustrated internal combustion engine I or 1 is a cross-flow type 4-stroke gasoline engine, and the engine body E includes a cylinder block 1 and a cylinder head 2 which is superimposed and bonded to two surfaces of the cylinder block 1 through a gasket 3. A piston 5 is slidably fitted into a cylinder 4 formed in the cylinder block 1. A combustion chamber 6 is recessed in the bottom surface of the cylinder head 2 at a portion facing the top surface of the piston 5. It consists of two ceiling slopes 71.7□.

One ceiling slope Fill 7 + has a pair of jq,
y',' 1, second intake valve o! 3. ,! 112?(y
The other ceiling slope 72 is opened in parallel along the plan LvC.
One exhaust valve port 10 is opened facing the first intake valve port 91 and facing the first intake valve port 91 . Further, a portion of this ceiling slope 7□ that mainly faces the second intake valve port 92,
In the illustrated example, the bottom [lI
A squish portion 11 is formed with a squish surface 11a at the same height as the bottom surface of the cylinder head 2, and a pair of torch nozzles 12 are provided on a side surface 11h of this cedar horn portion 11.
゜12 is the first intake valve port 9. It is opened by turning the finger.

At least one group of the side surface 11b is the second intake valve port 9.
□0 It is formed along the periphery.

Furthermore, a swirl guide 8 is provided on one side of the ceiling 71 so as to protrude from the periphery of the combustion chamber 60 so as to intervene between the intake valve ports 91 and 92. This swirl guide 8 is formed into a 1st guide 'ITTI 8 a with the 1[11+ plane along the periphery of the first intake valve port 91 standing upright like a cliff, and the swirl guide 8a is formed along the periphery of the second intake valve port 92. The second guide surface 8b is formed with a relatively gently inclined surface, and the bottom surface is formed as a squish surface 8C having the same height as the bottom surface of the cylinder head 2.

The cylinder head 2 has an intake boat 13 and an exhaust boat 1.
4 is formed, and the intake boat 13 has a first . The second branch bow 1'13.1' is divided into 132, and the first branch bow 1'13. It is connected to the second intake valve port 91-92, and its outer end is opened to one side of the cylinder head 2, and the opening is connected to the intake pipe 15 connected to the fuel supply device, for example, the carburetor C'.
are concatenated. By branching the intake boat 13 within the cylinder head 2 in this manner, the structure of the intake pipe 150 passage can be simplified. On the other hand, the exhaust boat 14 has an inner end connected to the exhaust valve port 10, an outer end connected to the other side surface of the cylinder head 2, and an exhaust pipe (not shown) connected to the opening.

1st. The second intake valve port 91,92 and the exhaust valve port 10 are
=il, second intake valve 18□, which is slidably supported on the cylinder head 2 via valve guides 161, 162゜17
, 182 and exhaust valve 19, and these valves 18, . 18□, 1
The valve train M for opening and closing 9 is in the cylinder head 2.
placed on top of the

The valve mechanism M includes valve springs 201.2 connected to the valves is, is2.19, respectively, and biasing the valves in the closing direction.
o□, 21, and the valves 181, 182゜19, m=note--22+, 22□, 23-τ in conjunction with each other. , 182.19 for each valve spring 2L
, 20□, 21, and a common camshaft 24 which can open against the elastic force of the valves 1B, , 182, by this valve operating mechanism Ai.

19 is given opening/closing timing as shown in FIG.

That is, the opening timing of the other second intake valve 182 is delayed with respect to the opening timing of the first intake valve 18° facing the exhaust valve 19, and the closing timing of both intake valves 1B, 182 is delayed. Let's match. In this way, the swirl of the air-fuel mixture that occurs during the intake stroke is strengthened, and each intake valve 09. ,9□
Therefore, the pulsating effect of the intake air acting on the combustion chamber 6 is not interfered with and reduced.

In addition, the exhaust valve 19 and the X, V, and second intake valves 18. .

182, there is a predetermined non-polymerization period 1 between each opening/closing timing.
．． , 12 are provided. In this way, exhaust gas backflow during low-speed operation can be minimized while scavenging can be effectively performed using exhaust inertia during high-speed operation, leading to improved performance in terms of both fuel efficiency and output.

Furthermore, both intake valves 18. , 182 are made substantially parallel to each other, thereby increasing the opening lift amount of the second intake valve 182 to the first intake valve 18 . It is smaller than that of . In relation to this, valve G″ of the second intake valve 182 with a small valve opening lift amount
:L 20. The spring force of the valve spring 201 is set to be weaker than that of the other valve spring 201. In this way, the valve opening torque of the camshaft 24 is reduced by the amount that the spring force of the valve spring 202 is weakened, and the internal loss of power is reduced.

A sub-combustion chamber 26 is formed in the cylinder head 2 above the squish portion 11 and is connected to the torch nozzle 12.12, and an electrode of a spark plug 25 screwed onto the cylinder head 2 faces the chamber 26.

Further, a sub-intake valve port 27 is opened on the upper surface of the chamber 26, and a sub-intake valve 29 for opening and closing the valve port 27 is provided. The auxiliary intake valve port 27 is communicated with an auxiliary fuel supply device, for example, an auxiliary carburetor AC via an auxiliary intake boat 30 provided in the cylinder head 2.

The auxiliary carburetor AC generates an air-fuel mixture whose fuel concentration is adjusted to be relatively favorable in terms of specific yield, while the carburetor C generates an air-fuel mixture whose fuel concentration is adjusted to be relatively lean. .

Next, let us explain the operation of this embodiment. When the engine is operated, during the intake stroke, a rich mixture generated by the auxiliary carburetor AC is sucked into the auxiliary combustion chamber 26, and a lean mixture is sucked into the combustion chamber 6. At this time, first the first intake valve 181 opens, so the first intake valve port 9. The air-fuel mixture that has flowed into the combustion chamber 6 from the /it old 1 intake valve port 9. is the ceiling slope 7. The r
Create a swirl in the direction of the arrow in figure i. Then the second intake valve 1
82 opens, the air-fuel mixture flowing from the second intake valve port 92 into the combustion chamber 6 is guided to the second guide surface 8b of the swirl guide 80 and the squish portion 110 11b, and similarly moves in the direction of the arrow in FIG. This causes a swirl and strengthens the swirl as it merges with the air-fuel mixture that previously flowed in from the first intake valve port 91. As a result, the air-fuel ratio of the air-fuel mixture in the combustion chamber 6 is made uniform.

When the ignition plug 25 ignites at the end of the compression stroke of the engine -11i', <, the rich air-fuel mixture in the auxiliary combustion chamber 26 ignites and becomes a flame, which is ejected from the torch nozzle 12.12 into the combustion chamber 6.
Inject it inside and burn the lean mixture.

By the way, in the case of such a torch ignition type engine, the main ignition point in the combustion chamber 6 caused by the flame from the torch nozzle 12.12 is located at a certain distance away from the torch nozzle 12.12), and in the case of the present invention, 1 intake valve 18. This corresponds to the neighborhood α of . Therefore, the lean air-fuel mixture ignited in the combustion chamber 6 is immediately carried by the swirl in the above direction to the vicinity of the exhaust valve 190, which is already in a high temperature state due to the influence of exhaust heat, so that the start of combustion is promoted. Ru.

In addition, during the compression stroke of the engine, the squish surface 1.1 d of the squish portion 11 and the squish surface 8C of the swirl guide 8 cooperate with the upper surface of the piston 5 to give squish to the air-fuel mixture in the combustion chamber 6. This makes it possible to increase the compression ratio and strengthen the flow of the air-fuel mixture.

As described above, according to the present invention, the ceiling surface of the combustion chamber is constituted by two ceiling slopes descending from a ridgeline in the approximately central portion toward both sides, and one ceiling slope has a first slope. A pair of first intake valves are opened and closed by a second intake valve. The second intake valve opening is parallel to the above-mentioned support.
On the other ceiling slope, an exhaust valve opening is opened at a position opposite to the first intake valve opening and is opened and closed by an air valve, and an exhaust valve opening is opened at a position opposite to the first intake valve opening. Since the torch nozzle is placed at the same position, the torch nozzle can be placed in a wide area, and the three valves do not interfere with the torch nozzle.
The V-hole can be freely arranged to obtain the desired performance, and it is easy to arrange several torch nozzles as in the above embodiment.

Further, on the one ceiling slope, there is a periphery of the combustion chamber which is inferior to the first ceiling slope.
．． Intervention 1 - A swirl guide extending in a protruding manner is provided between the second intake valve ports, and the swirl guide causes the UIL mixture from each intake valve port to flow from the intake valve port to the exhaust valve port. The opening direction of the torch nozzle was selected so that the main ignition point of the air-fuel mixture was formed in front of the exhaust valve port in the swirl direction, so that the air-fuel mixture In addition to achieving uniformity, the fuel is forced to pass around the high temperature exhaust valve immediately after ignition, which accelerates the start of combustion.
As a result, the combustion time is shortened, the -T combustion performance is improved, and the overall combustion is significantly improved, resulting in reduction in fuel consumption and improvement in output performance.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a bottom view of a cylinder head, FIG. FIG. 1 is a vertical cross-sectional view of an internal combustion engine taken along the lines 1--2 and 2-2, respectively, and is a diagram showing the opening/closing timing of the intake and exhaust valves of this engine. AC...auxiliary carburetor, C...carburizer, E...engine body, 7I4...valve mechanism, α...ignition point, L...
Ridge line 2... cylinder head, 4... cylinder, 5...
... Piston, 6... Combustion chamber, 7... Ceiling surface, 71
, 7□...Ceiling slope, 8...Swirl guide, 8α
...First guide surface, 8b...Second guide surface, 91-
92...1st. 2nd intake valve port, 10...exhaust valve port,
12... Torch nozzle, 181.18°... 1st.
2nd intake valve, 19...exhaust valve, Fig. 3, Fig. 2, Fig. 4, procedural amendment, ka) April 1980-51'' 1. Indication of the case 1982 Patent Application No. 209934, Title of the invention: 3-valve internal combustion engine; Relationship to the amended case Patent applicant name (532) Honda Motor Co., Ltd., representative
Person 〒105 Telephone Tokyo 434-4151' -) Date of amendment order

Claims (1)

[Scope of Claims] (1) The ceiling surface of the combustion chamber is composed of two ceiling slopes descending from a ridgeline in the approximately central part toward both sides, and one ceiling slope is provided with valves that are opened and closed by first and second intake valves. A pair of 41 + 2nd
Intake valve ports are opened in parallel along the ridge line, and one exhaust valve port is opened on the other ceiling slope at a position opposite to the first intake valve port and is opened and closed by an exhaust valve. 2
A torch nozzle is disposed at a position opposite to the intake valve port, and one side of the one ceiling is located closer to the first side than the periphery of the combustion chamber. A swirl guide extending so as to intervene between the second intake valve ports is provided, and a side surface of the swirl guide along the periphery of the first intake valve port allows the air mixture flowing from the first intake valve port to flow into the second intake valve port.
It is formed on the first guide surface that stands up in a precipitous manner to prevent the air from flowing toward the intake valve port 1Itil, and is also formed on the dotted surface along the periphery of the second intake valve port of this swirl guide. A three-valve internal combustion engine, wherein the opening direction of the torch nozzle is selected so that the main ignition point of the air-fuel mixture is formed in front of the exhaust valve port in the swirl direction of the air-fuel mixture generated in the air-fuel mixture. (2. In the item described in claim (1),
In the three-valve internal combustion engine, the opening direction of the torch nozzle is selected to face the first intake valve port. (3) Permissible percentage In what is stated in claim (1),
The torch nozzle is a three-valve type internal structure in which the other ceiling is opened at a side surface of a sales squish portion that protrudes from one side, and at least a portion of the side surface of the squish portion is formed along the periphery of the second intake valve port. Numbness. (4) In what is stated in claim (1),
A three-valve internal combustion engine, wherein the opening timing of the second intake valve is delayed from the opening timing of the first intake valve.