JPH08254121A - Spark ignition type internal combustion engine - Google Patents

Abstract

PURPOSE: To improve deterioration in the performance of ignition and improve the limit of knocking by supplying only a flamable mixture gas without recirculated exhaust gas mixed therein to the region around an ignition plug, though the exhaust gas cleaned by a three-dimensional catalyser is returned to an inlet pipe. CONSTITUTION: A mixture gas for example with an air exess ratio λ:1.0 is provided by a mixer 1 installed in an inlet port, so that the mixture gas is mixed with recirculated gas from an EGR pipe 4 branched off from an exhaust tube 3 on the way of introducing the mixture gas to an engine. A part of the exhaust gas not subjected to recirculating is cleaned by a three-dimensional catalyser 5. The concentration of the mixture gas is controlled according to a feedback from an oxigen sensor 10. Further, a part of the mixture gas without the recirculating gas mixed therein is picked out from a branch 7 which is located upstream than a junction 6 and down stream than the mixer 1, then the picked up gas is conducted near an ignition plug, allowing the mixture gas without EGR gas mixed therein and with the air exess ratio λ=l.0 to be ignited at the period of the ignition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spark ignition internal combustion engine which purifies exhaust gas by equipping the exhaust system with a three-way catalyst and keeping the ratio of air and fuel constant. The present invention relates to a configuration in which the air is recirculated to the intake side for combustion.

[0002]

2. Description of the Related Art Conventionally, in an internal combustion engine, control points by control means of two systems are automatically compared, and when these control points have a difference of a reference value or more set in advance, it is judged as abnormal. The technique of providing the means is known. For example, it is as in the technique described in JP-A-6-330791.

Further, the conventional three-way catalyst engine has the following problems. First, the heat load is high. Second
In addition, since the knocking is easy, the compression ratio cannot be increased and the thermal efficiency is poor. Third, the output is low due to knocking. There were problems such as. And, in order to solve the above-mentioned trouble, the lean burn method was adopted, but in the lean burn method, there were the following problems. First
, There is a limit to the NO _x reduction. Secondly, THC and CO are generated. Thirdly, the cost increases if an oxidation catalyst is provided to remove THC and CO. There was a problem such as.

[0004]

SUMMARY OF THE INVENTION The present invention overcomes the disadvantages of the prior art. According to the first aspect of the present invention, high output, high efficiency and high compression ratio characteristics of a lean burn engine are obtained while maintaining the purifying property of the three-way catalyst, that is, in a state where the residual O ₂ in the exhaust gas is zero. Therefore, a large amount of recirculated exhaust gas (EGR) (O ₂ is zero) is used to dilute the intake air-fuel mixture having an excess air ratio of 1.0. However, in this case, the mixed gas of the recirculated exhaust gas has a poor ignition performance and does not ignite with a normal ignition device, so only in the vicinity thereof,
Separately, a gas mixture containing no recirculated exhaust gas is supplied. By this operation, the limit of knocking by EGR is improved, the NO _X concentration by the recirculated exhaust gas is lowered, and the three-way catalyst can be made smaller.

According to a second aspect of the present invention, there is provided a three-way catalyst in the exhaust system, and a constant ratio of air to fuel is used to purify NO _X , CO and THC in the exhaust gas. in the engine, by incorporating recirculated exhaust gas, in a configuration for reducing the concentration of nO _X in the exhaust gas, as in claim 1, only the periphery of the spark plug 11, the air-fuel mixture is not mixed in the recirculated exhaust gas separately However, since the ignition stability changes sensitively, there is a problem that a stable ignition state cannot be obtained. In the present invention, the main combustion chamber, which is provided in the cylinder head or on the top surface of the piston, is provided with a sub-chamber having a volume isolated from the main combustion chamber so that the air-fuel mixture in which the recirculated exhaust gas is not mixed does not diffuse to the surroundings. A stable ignition state is obtained by supplying a gas mixture containing no recirculated exhaust gas only to the volume.

According to the third aspect of the present invention, the air-fuel mixture in which the recirculated exhaust gas is not mixed is further pressurized in the combustion chamber 13 to a pressure higher than the compression pressure, and the ignition plug is activated at a timing near the compression top dead center. It is to be injected near 11 to obtain stable ignition performance. As a result, the air-fuel mixture, which is supplied from the branch point 7 downstream of the mixer 1 to the combustion chamber 13 and does not contain the recirculated exhaust gas, diffuses inside the combustion chamber 13 to exert a predetermined effect. It solves the problem of not being performed.

The invention of claim 4 improves on the point that the invention of claim 3 copes with a load change by adjusting the pressure of the air-fuel mixture by means of the regulator 16, and improves the opening / closing timing of the supply valve 17 or the opening area of the valve. , Or both are controlled to respond to changes in the operating condition of the engine.

According to a fifth aspect of the invention, the timing sensor 30 is provided.
Is provided with a mechanism for directly supplying an air-fuel mixture containing no recirculated exhaust gas into the combustion chamber 13 at a certain timing, and a concave portion 25 is formed in the combustion chamber 13 as a supply place for supplying the recirculated exhaust gas. It is configured to prevent diffusion of air-fuel mixture that does not mix.

[0009]

Means for Solving the Problems Next, means for solving the problems will be described. In claim 1, a three-way catalyst is arranged in the exhaust pipe, and the three-way catalyst purifies exhaust gas,
In a spark ignition internal combustion engine equipped with a recirculation exhaust gas pipe that recirculates purified exhaust gas to an intake pipe, a combustible mixture containing no recirculation exhaust gas is supplied only around the spark plug. It was done.

According to a second aspect of the present invention, a spark is provided in which a three-way catalyst is arranged in the exhaust pipe, exhaust gas is purified by the three-way catalyst, and a recirculation exhaust gas pipe for returning the purified exhaust gas to the intake pipe is provided. In an ignition internal combustion engine, a combustible air-fuel mixture containing no recirculated exhaust gas is provided only around the spark plug, and the air-fuel mixture not mixed with the recirculated exhaust gas is separated from the combustion chamber. It was supplied indoors.

According to a third aspect of the present invention, there is provided a three-way catalyst in the exhaust pipe, the exhaust gas is purified by the three-way catalyst, and the recirculation exhaust gas pipe for returning the purified exhaust gas to the intake pipe is provided. In an ignition type internal combustion engine, a combustible air-fuel mixture containing no recirculated exhaust gas is provided only around the spark plug, and the air-fuel mixture containing no recirculated exhaust gas is higher than the cylinder compression pressure. The pressure is increased to supply the pressure around the spark plug.

According to a fourth aspect of the present invention, there is provided a three-way catalyst in the exhaust pipe, the exhaust gas is purified by the three-way catalyst, and a recirculation exhaust gas pipe for returning the purified exhaust gas to the intake pipe is provided. In an ignition type internal combustion engine, a combustible air-fuel mixture containing no recirculated exhaust gas is provided only around the spark plug, and the air-fuel mixture containing no recirculated exhaust gas is compressed by the cylinder compression pressure. By increasing the pressure to a high pressure and maintaining the pressure constant, control the injection timing and the lift of the supply valve, and mix according to the engine operating conditions, such as load, rotation speed, fuel type (city gas, propane). Air injection is performed.

According to a fifth aspect of the present invention, there is provided a three-way catalyst in the exhaust pipe, the exhaust gas is purified by the three-way catalyst, and a recirculation exhaust gas pipe for returning the purified exhaust gas to the intake pipe is provided. In an ignition-type internal combustion engine, a combustible mixture containing no recirculated exhaust gas is supplied only to the periphery of a spark plug, and a recess is provided in the cylinder head as the supply location, and ignition is performed in the recess. It has a plug and a supply valve.

[0014]

According to the first aspect of the present invention, the disadvantage that the ignition performance is deteriorated by the fuel mixed with the recirculated exhaust gas is supplied only to the periphery of the spark plug 11 with the mixture gas containing no recirculated exhaust gas. I was able to eliminate it. This improves the knocking limit, reduces NO _X ,
A spark ignition type internal combustion engine with a small three-way catalyst could be constructed.

According to the invention of claim 2, the spark plug 11
As compared with the case of claim 1, in which a gas mixture containing no recirculated exhaust gas is supplied to the periphery of the fuel cell, diffusion of the gas mixture containing no recirculated exhaust gas is prevented, so that the supply amount of the gas mixture is reduced. It needs less. Also, it is not easily affected by load and rotation fluctuation. It can also be implemented by modifying the existing lean burn engine.

According to the third aspect of the present invention, the air-fuel mixture which does not contain the recirculated exhaust gas is prevented from diffusing, and the air-fuel mixture which is likely to be ignited directly in the combustion chamber 13 is as close as possible to the ignition timing. By injecting, it is possible to obtain reliable and stable ignition performance. Further, since the injection amount of the air-fuel mixture in which the recirculated exhaust gas is not mixed can be small, the NO _x concentration itself can be further lowered.

According to the invention of claim 4, it occurs when the regulator 16 is controlled in the case of the invention of claim 3,
It was possible to improve the durability of the regulator 16 and the response delay when the load fluctuates by adjusting the timing of the supply valve 17 and the open area.

According to the invention of claim 5, in the compression stroke, the fuel is directly injected into the combustion chamber 13. However, depending on the shape of the combustion chamber 13, a strong flow phenomenon occurs near the top dead center of the compression, and The air-fuel mixture that does not mix the circulating exhaust gas is diffused. Therefore, in the present invention, the recess 25 is formed so as not to be easily affected by the flow phenomenon in the combustion chamber 13.

[0019]

EXAMPLE FIG. 1 is an intake / exhaust system diagram of a three-way catalyst system with an EGR pipe, FIG. 2 is a diagram showing improvement of knocking limit by mixing recirculated exhaust gas, and FIG. 3 is a diagram showing recirculated exhaust gas. FIG. 4 is a drawing showing the NO _X reduction effect by mixing, FIG. 4 is a drawing showing the relationship between the three-way catalyst capacity and the NO _X purification rate, and FIG. 5 is only the periphery of the spark plug without the inclusion of recirculated exhaust gas. FIG. 4 is a side sectional view showing an intake stroke of a combustion chamber configured to retain combustible air-fuel mixture and ensure ignition stability.

FIG. 6 is a side sectional view showing the exhaust stroke,
FIG. 7 is an intake / exhaust system diagram showing a configuration in which a compressor 14 applies pressure to the combustion chamber 13 to supply a mixture that does not mix the recirculated exhaust gas, and FIG. 8 mixes the recirculated exhaust gas compressed by the compressor 14. 10 is an intake / exhaust system diagram showing a configuration in which an unmixed air-fuel mixture is supplied via a regulator 16 and a supply valve 17, FIG. 9 is a diagram showing a correlation between a load and a pressure of the air-fuel mixture in which recirculated exhaust gas is not mixed, FIG. Is a drawing showing the timing of the piston and the opening / closing timing of the supply valve 17, and FIG. 11 is an intake / exhaust system diagram showing a configuration in which the supply timing of the air-fuel mixture that does not mix the recirculated exhaust gas is controlled by the opening / closing timing of the supply valve 17. .

FIG. 12 is a diagram showing control for changing the crank angle and the opening / closing timing of the supply valve 17, FIG. 13 is a diagram showing control for changing the correlation between the crank angle and the lift of the supply valve 17, and FIG. 14 is a cylinder. FIG. 17 is a side sectional view showing an intake stroke of a configuration in which a recess 25 is provided in the head, FIG. 15 is a side sectional view of the same compression stroke, and FIG. 16 is a side sectional view showing a configuration in which a trapezoidal recess 26 is provided in the cylinder head.
18 is a drawing showing a comparison between a recess 26 having a trapezoidal cross section and a recess 25 having a cylindrical shape, FIG. 18 is a drawing comparing the misfired state of the flame kernel in the recess 25, and FIG. 19 is a heat insulating layer 28 covering the inside of the recess 25. It is drawing which shows the state which was done.

In FIG. 1, a mixer 1 provided at an intake port creates a mixture with an excess air ratio λ = 1.0, and while the mixture is introduced into an engine, recirculated exhaust gas branched from an exhaust pipe 3. The recirculated gas from the tubes, the EGR tube 4, is mixed and directed to the engine. The portion of the exhaust gas that has not been recirculated passes through the exhaust pipe 3 and is purified by the three-way catalyst 5.

The concentration of the intake air-fuel mixture is controlled by the feedback from the oxygen sensor 10 as in the conventional three-way catalyst engine, and is maintained appropriately. Further, a part of the air-fuel mixture in which the recirculated exhaust gas is not mixed is withdrawn from the branch point 7 of the EGR pipe 4 and the intake pipe 2 upstream of the confluence 6 and the downstream of the mixer 1, and this is removed at a certain timing inside the cylinder. Is guided to the vicinity of the spark plug, and at the ignition timing, the air-fuel mixture having the excess air ratio λ = 1 in which the EGR gas is not mixed near the plug is ignited.

It has been considered that the engine equipped with the EGR pipe 4 has a large system and a high cost. However, the NO _X concentration can be reduced except for the poor ignition performance, and the engine can be knocked in the same manner as the lean burn engine. It has the advantage that the limit can be raised. Therefore, if the ignitability can be improved, an internal combustion engine with high output, low NO _x concentration and high efficiency can be obtained. In FIG. 2, the correlation of the load% that causes knocking with a change in the amount of recirculated exhaust gas is illustrated. Since the load% that causes knocking increases as the amount of recirculated exhaust gas increases, it is shown that the occurrence rate of knocking can be reduced.

[0025] In Figure 3, the magnitude of the recirculated exhaust gas quantity, indicates the magnitude of the NO _X, the mixing ratio of the recirculated exhaust gas is large, it can be understood that the NO _X is reduced.
However, if the mixing ratio of the recirculated exhaust gas is increased, the ignition rate becomes worse. In FIG. 4, the relationship between the three-way catalyst capacity and the NO _X purification rate is shown. Regulation target value of the NO _X in order is constant, NO emitted from the engine
_{If X} itself becomes low, the target value can be sufficiently achieved even if the purification rate becomes low. That is, it is possible to reduce the cost by reducing the size of the three-way catalyst.

5 and 6 show the intake stroke and the compression stroke in the state where the air-fuel mixture which does not mix the recirculated exhaust gas is supplied around the spark plug 11. When the supply valve 17 is opened / closed to suck the air-fuel mixture which does not mix the recirculated exhaust gas at the time of intake, and the air-fuel mixture which does not mix the recirculated exhaust gas is positioned around the ignition plug 11, ignition is performed in the compression stroke. Around the plug 11, a large amount of air-fuel mixture does not mix the recirculated exhaust gas, and the ignition plug 11 can improve ignition accuracy.

Next, referring to FIG. 7, the invention of claim 2 will be described. Regarding the structure of the basic spark ignition internal combustion engine,
It is the same as the configuration of FIG. 1 showing the configuration of claim 1. According to the second aspect of the present invention, as shown in FIG. 7, the air-fuel mixture which does not contain the recirculated exhaust gas introduced directly into the combustion chamber 13 from the branch point 7 downstream of the mixer 1 is In the case of the invention, it is supplied to the sub chamber 12 provided above the combustion chamber 13. The method of supplying the air-fuel mixture from the branch point 7 downstream of the mixer 1 to the auxiliary chamber 12 is the combustion chamber 1
There are both a case where it is naturally supplied in the intake stroke as in the case of directly supplying it to the compressor No. 3 and a case where the compressor 14 is provided and the compressor 14 is supplied to the compression stroke of the combustion chamber 13 through the accumulator 15. The more stable combustion can be achieved by supplying the fuel in the compression stroke via 14 and the accumulator 15.

Next, referring to FIG. 8, the invention of claim 3 will be described. The overall configuration is the same as that of the first aspect of the invention shown in FIG. 1, but the excess air ratio λ = 1.0 branched from the branch point 7 in the downstream of the mixer 1 and free of recirculated exhaust gas.
The air-fuel mixture is compressed by the compressor 14 until the pressure becomes higher than the compression pressure in the combustion chamber 13, and is stored in the accumulator 15. From this accumulator 15, let the supply valve 17 pass, and at the timing shown in FIG.
The air-fuel mixture is injected into the combustion chamber 13. Further, as shown in FIG. 9, the regulator 16 supplies pressure according to the load so that the injection amount can be adjusted by the rotation speed load. As the load, signals from the load detector 18 provided in the intake manifold, the timing sensor 30 provided in the crankshaft portion, and the oxygen sensor 10 are transmitted to the controller 20. The result of this determination is made by the recirculation exhaust gas control valve 21, the regulator 16 and the air-fuel ratio control valve 22.

Also in the invention of claim 5, the basic intake and exhaust systems are the same. Then, as shown in FIGS. 14 and 15, a recess 25 is provided. In the intake stroke, a mixture that does not mix the recirculated exhaust gas is separately supplied into the recess 25. During the intake stroke, the air-fuel mixture that does not mix the recirculated exhaust gas is filled to the extent that the recess 25 is filled. In the compression stroke shown in FIG. 15, the air-fuel mixture in which the recirculated exhaust gas is mixed enters the combustion chamber 13, and the air-fuel mixture in which the recirculated exhaust gas is not mixed is compressed to a volume corresponding to the compression ratio. Spark plug 11
By setting the size of the concave portion 25 so that the position of is located within the volume after compression, a stable ignition state can be obtained. If the high-pressure air-fuel mixture is directly charged in the compression stroke, it is possible to ignite more reliably.

Next, the configuration shown in FIGS. 16 and 17 will be described. In this structure, a trapezoidal recess 26 having a trapezoidal cross section is provided in the combustion chamber 13 as a supply place of the air-fuel mixture that does not mix the recirculated exhaust gas. It has a trapezoidal shape. The spark plug 11 and the supply valve 17 are arranged at the deepest part of the trapezoidal recess 26.

With this structure, the cross-section trapezoidal recess 26 has a smaller cross-sectional area as it goes deeper, which increases the degree of freedom in arranging the spark plug 11 and the supply valve 17 and reduces the volume of the recess. That is, low NO _x has become possible. That is, as shown in FIG. 17, the compression ratio is 8
In the case of, the height is compressed to only half, so
The degree of freedom in mounting the spark plug 11 and the supply valve 17 is great. When the compression ratio is 8 in the case of the cylindrical recess 25 as in the other configuration, the height becomes 1/8, so that it is difficult to attach the spark plug 11 and the supply valve 17 to each other. Further, the volume of the entire concave portion is only one third, NO _X is reduced, and the supply amount of the air-fuel mixture that does not mix the recirculated exhaust gas is small, so that the apparatus can be downsized. .

The configuration shown in FIGS. 18 and 19 will be described. In this configuration, the wall surfaces of the recessed portion 25 and the trapezoidal recessed portion 26 are covered with a heat insulating material so as to be in a heat insulating state to reduce heat loss and ensure ignition stability. This configuration does not reduce the heat loss by heat insulation and improve the thermal efficiency, but as shown in FIG. 18, prevents the flame kernel configured only for ignition from being cooled and misfiring. That is the purpose. Accordingly, in the lean-burn or partial stratification, and stable ignition, a further dilution by recirculated exhaust gas amount increases, it is of low NO _X can be achieved.

[0033]

As described above, according to the first aspect of the present invention, there is a drawback that the ignition performance is deteriorated with the fuel mixed with the recirculated exhaust gas. It was possible to solve it by supplying it. As a result, the knocking limit was improved, NO _x was reduced, and a spark ignition internal combustion engine with a small three-way catalyst could be constructed.

Since it is configured as in claim 2, as compared with the case of claim 1 in which a mixture gas containing no recirculation exhaust gas is supplied to the periphery of the spark plug 11, a mixture mixture containing no recirculation exhaust gas is provided. Since the diffusion of air is prevented, the supply amount of air-fuel mixture can be small. Also, it is not easily affected by load and rotation fluctuation. It can also be implemented by modifying the existing lean burn engine.

Since the air-fuel mixture according to the third aspect is configured to prevent diffusion of the air-fuel mixture containing no recirculated exhaust gas, the air-fuel mixture which is likely to be ignited directly in the combustion chamber 13 at a time as close as possible to the ignition timing. By injecting, it is possible to obtain reliable and stable ignition performance. Since The injection amount of the contaminating non-air mixture in the recirculation exhaust gas requires less, it is is able to further reduce the NO _X concentration itself.

According to the fourth aspect of the invention, the low durability of the regulator 16 and the response delay when the load fluctuates, which occur when the regulator 16 is controlled in the case of the third aspect of the invention, are supplied. This could be improved by adjusting the timing of the valve 17 and the open area.

According to the fifth aspect of the present invention, in the compression stroke, the fuel is directly injected into the combustion chamber 13. However, depending on the shape of the combustion chamber 13, a strong flow phenomenon occurs near the top dead center of the compression, The air-fuel mixture that does not mix the recirculated exhaust gas is diffused. Therefore, in the present invention, the recess 2 is formed so as not to be affected by the flow phenomenon in the combustion chamber 13.
5 is configured.

[Brief description of drawings]

FIG. 1 is an intake / exhaust system diagram of a three-way catalyst system with an EGR pipe.

FIG. 2 is a drawing showing improvement of knock limit by mixing recirculated exhaust gas.

FIG. 3 is a drawing showing the effect of reducing NO _x by mixing recirculated exhaust gas.

FIG. 4 is a drawing showing the relationship between the three-way catalyst capacity and the NO _x purification rate.

FIG. 5 is a side cross-sectional view showing an intake stroke of a combustion chamber having a structure in which a combustible gas mixture containing no recirculated exhaust gas is retained only around a spark plug to secure ignition stability.

FIG. 6 is a side sectional view showing the same exhaust stroke.

FIG. 7 is an intake / exhaust system diagram showing a configuration in which pressure is applied to the inside of a combustion chamber 13 by a compressor 14 and an air-fuel mixture that does not mix recirculated exhaust gas is supplied.

FIG. 8 shows a regulator 16 and a supply valve 1 for the air-fuel mixture that is compressed by the compressor 14 and does not contain the recirculated exhaust gas.
7 is an intake / exhaust system diagram showing a configuration for supplying via 7;

FIG. 9 is a drawing showing the correlation between the load and the pressure of the air-fuel mixture in which recirculated exhaust gas is not mixed.

FIG. 10 is a drawing showing the timing of the piston and the timing of opening and closing the supply valve 17.

FIG. 11 is an intake / exhaust system diagram showing a configuration in which the supply timing of the air-fuel mixture that does not mix the recirculated exhaust gas is controlled by the opening / closing timing of the supply valve 17.

FIG. 12 is a view showing control for changing the crank angle and the opening / closing timing of the supply valve 17.

FIG. 13 is a diagram showing control for changing the correlation between the crank angle and the lift of the supply valve 17;

FIG. 14 is a side sectional view showing an intake stroke of a configuration in which a recess 25 is provided in a cylinder head.

FIG. 15 is a side sectional view of the compression stroke.

FIG. 16 is a side sectional view showing a configuration in which a trapezoidal sectional recess 26 is provided in the cylinder head.

FIG. 17 is a drawing showing a comparison between a recessed portion having a trapezoidal cross section and a recessed portion 25 having a tubular shape.

FIG. 18 is a drawing for comparing the state of misfire of the flame kernel in the recess 25.

FIG. 19 is a view showing a state in which a heat insulating layer 28 covers the inside of a recess 25.

[Explanation of symbols]

 1 Mixer 4 EGR pipe 6 Confluence point 7 Branch point of the downstream of mixer 1 Spark plug 13 Combustion chamber 14 Compressor 15 Accumulator 16 Regulator 17 Supply valve

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location F02M 25/07 570 F02M 25/07 570P 580 580B

Claims (5)

[Claims] 1. A spark ignition system in which a three-way catalyst is arranged in an exhaust pipe, exhaust gas is purified by the three-way catalyst, and a recirculation exhaust gas pipe is provided for returning exhaust gas before or after purification to an intake pipe. A spark ignition type internal combustion engine, characterized in that a combustible mixture containing no recirculated exhaust gas is supplied only to the periphery of the spark plug in the internal combustion engine. 2. A spark ignition system in which a three-way catalyst is arranged in an exhaust pipe, exhaust gas is purified by the three-way catalyst, and a recirculation exhaust gas pipe is provided for returning exhaust gas before or after purification to an intake pipe. In an internal combustion engine, a combustible air-fuel mixture containing no recirculated exhaust gas is supplied only to the vicinity of a spark plug, and the air-fuel mixture containing no recirculated exhaust gas is separated from a combustion chamber. A spark ignition type internal combustion engine characterized by being supplied to. 3. A spark ignition system in which a three-way catalyst is arranged in an exhaust pipe, exhaust gas is purified by the three-way catalyst, and a recirculation exhaust gas pipe is provided for returning exhaust gas before or after purification to an intake pipe. In the internal combustion engine, a combustible air-fuel mixture containing no recirculated exhaust gas is supplied only to the vicinity of the spark plug, and the air-fuel mixture containing no recirculated exhaust gas is higher than the compression pressure in the cylinder. A spark ignition internal combustion engine, characterized in that it is configured to boost the pressure and supply it to the periphery of an ignition plug. 4. A spark ignition system in which a three-way catalyst is arranged in an exhaust pipe, exhaust gas is purified by the three-way catalyst, and a recirculation exhaust gas pipe is provided for returning exhaust gas before or after purification to an intake pipe. In an internal combustion engine, a combustible mixture containing no recirculated exhaust gas is supplied only around the spark plug, and the mixture containing no recirculated exhaust gas is higher than the cylinder compression pressure. A spark ignition internal combustion engine characterized in that the injection timing and the lift of a supply valve are controlled to perform mixture injection according to the operating condition of the engine by increasing the pressure and maintaining the pressure constant. 5. A spark ignition system in which a three-way catalyst is disposed in an exhaust pipe, exhaust gas is purified by the three-way catalyst, and a recirculation exhaust gas pipe is provided for returning exhaust gas before or after purification to an intake pipe. In a type internal combustion engine, a combustible mixture containing no recirculated exhaust gas is supplied only to the periphery of a spark plug, and a recess is provided in the cylinder head as the supply location, and a spark plug is provided in the recess. A spark ignition type internal combustion engine characterized in that a supply valve and a supply valve are arranged.