KR20020031119A - Inducing self-ignition device and its method for spark ignition in an internal combustion engine - Google Patents

Abstract

PURPOSE: An auto-ignition inducing apparatus of a spark ignition engine and a method thereof are provided to reduce fuel consumption and pollution, and to improve efficiency by burning mixed air drastically with supplying combustion gas ignited in an auxiliary chamber to a main chamber and with guiding auto-ignition of mixed air. CONSTITUTION: A combustion chamber of a spark ignition engine is composed of a valve, a cylinder block, a piston and a cylinder head(4). A cap(8) having plural communication holes(6) and an auxiliary chamber(7) is combined with the cylinder head to place an electrode of an ignition plug(5) in the auxiliary chamber, and the combustion chamber is divided into the auxiliary chamber and a main chamber. Mixed air in the auxiliary chamber is ignited with spark discharge, and combustion gas is supplied to the main chamber. Combustion time is reduced with igniting mixed air simultaneously at multiple points in the main chamber. Fuel consumption and harmful gas are reduced, and thermal efficiency is increased.

Description

Inducing self-ignition device and its method for spark ignition in an internal combustion engine}

The present invention relates to an apparatus and a method for inducing self-ignition of a mixer supplied to a combustion chamber in a spark ignition engine, which is a kind of an internal combustion engine, and more particularly, a combustion gas ignited by a spark plug in a poor part of a combustion chamber to a main chamber. The present invention relates to a self-ignition induction apparatus and a method of a spark ignition engine that can induce self-ignition of a mixer supplied to a main chamber and rapidly burn a mixer having a low equivalent ratio to obtain fuel savings, high thermal efficiency, and low pollution.

The conventional spark ignition engine is a spark plug which supplies ignition energy to the mixer to realize combustion. A flame nucleus is formed around the spark plug, and a hot reaction surface is formed in which the flame nucleus is the flame surface. As it propagates, the combustion of the mixer is terminated through sequential combustion. In such a spark ignition engine, it is desirable to perform combustion as fast as possible near the top dead center in order to increase the thermal efficiency, and the improper ignition timing causes problems such as a decrease in output, waste of fuel, and an increase in harmful emissions due to incomplete combustion. have. Therefore, realization of high power and complete combustion is required as fast combustion as possible near top dead center.

In addition, in order to prevent fossil energy depletion and air pollution, regulations on fuel efficiency and emission gas of automobiles are gradually being tightened. Therefore, in order to develop high efficiency and low pollution engines in accordance with the current trend, a number of technologies have been developed in related fields. As a result, lean burn engines, GDI engines, and premixed compression engines are typical.

The lean burn engine was developed by applying a method of burning a thinner mixer compared to the existing engine. The lean burn engine is known to increase HC, reduce NOx and CO, and obtain high efficiency. The GDI engine is fueled according to load in order to obtain high efficiency and low pollution. In order to change the injection timing and to stratify the mixer, the flow chamber is improved. However, the above-described lean combustion engine is a combustion system that secures its shortcomings as it causes problems such as misfire in lean region, wide air-fuel ratio control, and smoke generation at high load. It is progressing recently.

Combustion of the premixed compression ignition engine is a combustion method that combines the type of supplying a premixer of a gasoline engine and the combustion method through self-ignition of fuel in a diesel engine, taking advantage of a gasoline engine and a diesel engine, thereby achieving high efficiency and low pollution. It is attracting attention as a next-generation engine that expects simultaneous realization, and is equipped with PREDIC (FREmixed-charge Diesel Ignited Combustion), HCDC (Homogeneous Charge Diesel Ignited Combustion), PCCI (Premixed-charge combustion Ignition), HCCI (Homogeneous Charge Compression Ignition), and ATAC (ATAC) Active Thermo Atmosphere Combustion).

Among the engines, HCCI (Homogeneous Charge Compression Ignition) is a four-stroke SI engine that realizes uniform self-ignition at high compression ratio and high temperature premixer, unlike conventional spark ignition method, and throttling at low load Because it can be operated without the fuel economy, it provides the same fuel economy as diesel engine, and it can operate at full load with uniform air supply in the same engine, so it can get higher specific power than the gasoline engine. Compared with conventional engines, the emissions are very low.

Active Thermo Atmosphere Combustion (ATAC) has applied this technology to engines for small generators. Recently, a number of new studies on ATAC have been introduced. Most studies show that high efficiency and high output can be achieved by rapid combustion due to the relatively low level of hazardous emission characteristics and multi-point self-ignition, such as the conventional lean burn engine, due to the combustion of the lean mixture, but the target is limited to the two-stroke engine. In addition, a very high amount of residual gas is required for a wide range of operation and ignition stability, and a small amount of residual gas is required for application to a four-stroke engine.

It is an object of the present invention to reduce fuel consumption, reduce harmful emissions and increase thermal efficiency, through combustion, which avoids the conventional combustion method of propagating the flame surface and reaches the self-ignition conditions of the mixer much earlier, The magnetism of internal combustion engines simultaneously ignites the mixer in the main chamber to reduce the time loss of flame propagation combustion, enabling rapid combustion, and allowing the combustion of mixers with a sparse equivalence ratio compared to the conventional combustion methods of flame ignition engines. The present invention provides an ignition induction device and a method thereof.

1 is a detailed view of the present invention

Figure 2 is an intake stroke state diagram in the engine using the present invention

Figure 3 is a state of compression stroke in the engine using the present invention

Figure 4 is an exploded stroke state diagram in the engine using the present invention

5 is a combustion pressure change diagram when the equivalent ratio 1.0 of the engine using the present invention

6 is a combustion pressure change diagram when the equivalent ratio of the engine 0.8 using the present invention

<Explanation of symbols for the main parts of the drawings>

1: valve 2: cylinder block 3: piston

4: cylinder head 5: spark plug 6: contact hole

7: insolvent 8: cap 9: main chamber

Hereinafter, the configuration and operation of the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, the combustion chamber is composed of a valve (1), a cylinder block (2), a piston (3), and a cylinder head (4), and a mixer is ignited by an ignition plug (5) installed in the cylinder head (4). A flame ignition engine in which a flame nucleus is formed around (5) and a flame plane, which is a high-temperature reaction surface on which a flame nucleus is developed, propagates by magnetic force and is sequentially burned to terminate combustion of a mixer in a combustion chamber. The cylinder head 4 is provided with a fastening means such that a downwardly convex hemispherical cap 8 with a ball 6 formed therein and an insulator 7 formed therein is positioned so that the electrode of the spark plug 5 is located in the center of the insulator 7. It is fastened to the conventional combustion chamber is characterized in that it is divided into a compartment (7) and the main chamber (9).

According to the present invention, the mixture of fuel and air formed in the main chamber 9 flows into the sub chamber 7 through the contact hole 6 during the compression stroke, and when the spark ignition occurs at the end of the compression stroke, the sub chamber 7 Of the main chamber (9) is combusted and ejected into the main chamber (9).

The present invention is characterized in that the structure of the failure chamber 7 does not have a separate fuel supply device, so that a conventional engine can be easily modified and used, and the volume of the failure chamber 7 and the number and height of the contact holes 6 are different. The ratio of diameter to diameter is an important dimension that greatly affects the combustion of the mixer and changes with the volume of the engine and main chamber 9.

In the combustion process of a conventional spark ignition engine, a flame nucleus is formed around an electrode by a spark discharge, and the flame nucleus develops into a flame surface, and the flame surface is a continuous and sequential exothermic chemical reaction in the surrounding mixer. It propagates to the end of the combustion chamber and combustion ends.

Compared to the above, in the present invention, when combustion occurs in the subsidiary chamber 7 by spark ignition at the end of the compression stroke, the combustion gas in the subsidiary chamber 7 is ejected to the main chamber 9 through the contact hole 6 at a sudden pressure rise. And a chemical method is actively used for combustion of the main chamber (9) mixer. At this time, the combustion products are ejected from the subsidiary chamber 7 to a large area of the main chamber 9 and cause combustion by self-ignition of the main chamber 9 mixer through chemical reaction with the mixer existing in the main chamber 9. .

The combustion method according to the present invention shortens the combustion time compared to the conventional method. That is, time loss of the internal combustion engine can be reduced by achieving rapid combustion. Theoretically, the shorter the time from the start of combustion to the end, the higher the efficiency of the engine. Therefore, the present invention achieves a high efficiency engine because it achieves rapid combustion as compared to a conventional engine. In addition, when the rapid combustion is achieved, knocking of the gasoline fuel can be prevented, so that the compression ratio of the internal combustion engine can be increased to operate. Theoretically, an increase in compression ratio leads to an increase in thermal efficiency, which is another reason for producing an engine of high efficiency with the present invention.

The combustion through the present invention, unlike the conventional spark ignition engine, is a combustion method of self-igniting the mixer of the main chamber 9, so that the range of the flammability limit of the mixer can be extended. In the conventional combustion method, combustion is mainly achieved by using the stratified technique to expand the flammable range or by improving the flow in the combustion chamber to induce a rich mixer near the spark plug 5, but this is difficult to control the mixer, Risks are reported. However, the present invention uses a self-ignition combustion method in a spark ignition engine, so that even if the air-fuel ratio is lean, sufficiently controlled combustion is possible. And it is not necessary to use a method of increasing the concentration of the mixer on the spark plug 5 side like the stratified supercharge engine. If a homogeneous mixer is made in the main chamber 9 and only ignition occurs in the sub chamber 7, self ignition occurs in the main chamber 9, so that combustion is achieved even in a lean air-fuel ratio. As a result, even if a small amount of fuel is supplied, combustion can be made rapidly, resulting in an engine of high efficiency and low pollution.

Embodiments in an actual engine of the present invention are shown in FIGS. That is, FIG. 2 shows a state in which the mixer is formed in the main chamber 9 at the suction stroke, and FIG. 3 shows the combustion gas generated by the spark ignition at the end of the compression stroke from the sub-room 7 to the main chamber 9. The ejected form is shown, and FIG. 4 shows the form in which the mixer of the main chamber 9 is simultaneously ignited by the injected ejected combustion gas.

In addition, experimental results confirming the characteristics of combustion according to the present invention using a static combustion modeled after the spark ignition engine are shown in Figs. 5 to 6, which compare the present invention with the conventional properties according to the equivalent ratio. .

The size of the auxiliary chamber 7 used in the experiment was 2cc in volume, 2mm in thickness, 11 contact holes 6, the diameter of the contact hole 6 was 1.5mm, and the volume of the main chamber 9 was 400cc. to be. The direction of the contact hole 6 from the subsidiary chamber 7 to the main chamber 9 is formed at equal intervals with an angle of about 60 degrees with respect to the central axis. The spark plug 5 is used in a typical automobile engine, and the shape of the failure chamber 7 and the positional relationship between the failure chamber 7 and the spark plug 5 are shown in FIG. 1.

FIG. 5, which is a result of the above experiment, shows a change in combustion pressure according to the elapsed time after the spark discharge compared with that according to the present invention and that according to the conventional method, and the experimental condition is n-heptane, equivalent ratio 1.0 , Temperature and pressure are 403K and 0.5MPa. The combustion pressure was measured using a Kiesler pressure transducer and a signal amplifier. Here, the equivalence ratio is a dimensionless number used in combustion engineering and is a measure of the degree of fuel contained in the fuel + air mixer. In general, when the equivalent ratio is 1 or more and below, the expressions of fuel rich and fuel lean are used respectively, and the lean burn engine is mainly used to represent an engine capable of running in a lean state of fuel.

According to the results shown in FIG. 5, the method according to the present invention showed a shorter ignition delay time, a rapid pressure increase rate, and a higher peak pressure than the conventional method.

Figure 6 is equivalent to 0.8, the rest of the conditions are the same as the experimental conditions of Figure 5, the results of the present invention compared to the conventional method is shorter ignition delay time, pressure rise rate is sharp, the maximum pressure is more high.

5 to 6, the characteristic pressure diagram of the present invention as shown in the results of FIGS. 5 to 6 is a combustion of only the spark plug 5, which is a conventional combustion method, compared with the sequential combustion of the mixer. Combustion according to the invention is the result of the combustion gas induced in the jet chamber 7 causing simultaneous multi-point self ignition of the main chamber 9 mixer.

Therefore, the use of the present invention can shorten the ignition delay, sharpen the combustion, and obtain more stable combustion at a lean equivalent ratio, thereby enabling a high efficiency and low pollution engine.

As described above, the present invention ignites the mixer in the subsidiary chamber 7 by spark discharge, supplies its combustion gas to the main chamber 9, and simultaneously ignites the mixer in the main chamber 9, so that the time of the conventional flame propagation type combustion has. It has the effect of reducing the loss and enabling rapid combustion, the effect of combustion of the mixer with a thinner equivalent ratio, the effect of saving fuel, reducing harmful emissions and increasing the thermal efficiency, thereby enabling high efficiency and low pollution engines. There is.

Claims (4)

In a spark ignition engine comprising a combustion chamber composed of a valve (1), a cylinder block (2), a piston (3), and a cylinder head (4), a plurality of communication holes (6) are formed and a cap (7) is formed therein. (8) is fastened to the cylinder head (4) so that the electrode of the spark plug (5) is located inside the sub chamber (7) so that the combustion chamber is divided into the sub chamber (7) and the main chamber (9). Self-ignition induction device of the engine. The device of claim 1, wherein the cap (8) is formed in a hemispherical shape convex downward. The spark ignition engine according to claim 1, characterized in that the contact hole (6) is formed at equal intervals with a specific angle such that the direction from the subsidiary chamber (7) to the main chamber (9) is lowered outward with respect to the central axis. Self-ignition induction device. The mixer is ignited by the spark plug 5 installed in the cylinder head 4, and a flame nucleus is generated around the spark plug 5, and the flame plane, which is a high-temperature reaction surface on which the flame nucleus is developed, is propagated by magnetic force and is sequentially In the spark ignition engine in which the combustion of the mixer in the combustion chamber is terminated through combustion, the mixer introduced into the subsidiary chamber 7 is ignited and burned by the spark plug 5 at the end of the compression stroke, and the ignition and burned combustion product is supplied to the main chamber 9. And a combustion product ejected into the main chamber (9) causes combustion by self-ignition in the main chamber (9) mixer through chemical reaction with the mixer present in the main chamber (9). Induction method of self ignition.