JPH03185213A - Fuel feeding device of stratified charge combustion internal combustion engine - Google Patents

Abstract

PURPOSE:To improve the fuel consumption and the exhaust gas purification efficiency in an engine which furnishes two suction ports to each cylinder and generates a barrel swirl to the mixture gas in a combustion chamber, by specifying the local equivalence ratio fed through one side suction port near an ignition plug. CONSTITUTION:In a four-cylinder engine 1 furnishing two suction ports 3 and 4 to each cylinder 2 respectively, the suction ports 3 and 4 are connected to the branch pipes 5a and 5b of a suction manifold 5, and arranged to blow the suction air to each combustion chamber 7 downward obliquely to the reciprocating direction of each piston 8. And the first and the second electromagnetic type fuel injection valves 91 and 92 are provided to each suction port 3 and 4, and an ignition plug 10 is provided to a cylinder head 2a near the opening end of the suction port 3. In this case, the fuel feeding by the fuel injection valves 91 and 92 is controlled to make the local equivalence ratio fed through the suction port 3 near the ignition plug 10 less than a limit value set depending on the smoke exhaust amount.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a stratified combustion internal combustion engine capable of generating barrel swirl (tumble flow) in the air-fuel mixture in a combustion chamber, and particularly to a stratified combustion internal combustion engine capable of generating a barrel swirl (tumble flow) in the air-fuel mixture in a combustion chamber. Regarding the supply device.

[Prior Art] Conventionally, a mixture with a rich air-fuel ratio and a lean mixture or air are supplied to the combustion chamber of a cylinder from at least two intake ports in a stratified (non-uniform) manner, resulting in lean combustion as a whole. Therefore, stratified combustion internal combustion engines have been proposed that aim to improve fuel efficiency, reduce CO emissions, and improve low knock performance.

In this type of cylinder, a stratified barrel swirl (tumble flow) is generated in the cylinder by the cylinder heated combined air flow supplied from the above two intake ports, and one of the intake ports located eccentrically from the center of the cylinder is generated. Inject fuel only into
By installing a spark plug on the intake port side where the fuel is injected at a position eccentric from the center of the cylinder, that is, in the area where the air-fuel ratio is rich, combustion is relatively stable compared to conventional engines even when the air-fuel ratio is lean. It is known that it can be obtained.

To explain this in more detail using FIGS. 28 and 29, the illustrated stratified combustion internal combustion engine is a four-cylinder gasoline engine 1, and each cylinder 2 has two independent intake ports 3. , 4 (intake valves not shown) are provided, thereby forming a two-intake valve engine.

Each intake port 3, 4 is connected to 7 of the intake manifold 5.
In addition to being connected to branch pipes 5a and 5b, the intake manifold 5 is also connected to an intake pipe (not shown) via a throttle valve 6 from a surge tank 5c.

Furthermore, the intake ports 3 and 4 have their planar projection axes X,
Y is arranged so that it is substantially perpendicular to the diameter of the cylinder along the centerline CL of the engine, and the intake air is blown into the combustion chamber 7 obliquely downward with respect to the reciprocating direction of the piston 8. It has become.

One intake port 3 is equipped with an electromagnetic fuel injection valve (
An ignition plug 10 facing the combustion chamber 7 is provided in the cylinder head 2a near the open end of the intake port 3 to which fuel is supplied to each cylinder 2.

To explain the operation of the stratified combustion internal combustion engine configured in this way, first, during the intake stroke of the engine 1, as the piston 8 descends, the air-fuel mixture and air flow through each intake port 3 and 4.
is drawn into the combustion chamber 7. At this time, one intake port (ignition plug side intake port) 3 near the spark plug 0
In this case, fuel is injected from the fuel injection valve 9 and a mixture of air and fuel is sucked into the combustion chamber 7, while only air is sucked from the other intake port (non-spark plug side intake port) 4. Ru.

Each of the intake ports 3 and 4 has its respective planar projection axis X,
Since Y is substantially perpendicular to the diameter of the cylinder and located at symmetrical positions, most of the air-fuel mixture and air taken into the combustion chamber 7 are separated into layers along the reciprocating direction of the piston 8. It flows as so-called barrel swirls C and D and turns. Here, C is the barrel swirl of the mixture, and D is the barrel swirl of the air.

In this way, the intake air taken into the combustion chamber 7 is compressed in the subsequent compression stroke, and then ignited by the ignition plug 10 installed near the open end of the intake port 3. Since the layers are swirling while being separated, the air-fuel mixture burns stably.

In other words, if the air-fuel mixture supplied from the intake port 3 to the combustion chamber 1 is set to have a rich air-fuel ratio, even if the air-fuel mixture together with the air supplied from the intake port 4 has a lean air-fuel ratio as a whole. This ensures stable combustion.

Such lean combustion has excellent anti-knock properties and contributes to improvements in fuel efficiency and CO emissions.

[Problems to be Solved by the Invention] However, in such a conventional N-burning internal combustion engine, during operating conditions that require an acceleration increase in fuel, outside of the lean feedback region such as during acceleration operation, the fuel is supplied to one side. Injecting only into the intake port may cause smoke.

By the way, the inventor of the present invention learned through experiments that one of the causes of smoke generation is that the equivalence ratio φ of the air-fuel mixture on the ignition side (that is, on the ignition plug side intake port side) is too rich. Ta.

That is, the relationship between the equivalence ratio φ (or air-fuel ratio) at the ignition plug side intake port 3 and the smoke emission amount is shown in FIG. 30, and from this FIG. It can be seen that the amount of smoke generation begins to increase when the value exceeds 1. Furthermore, when the equivalence ratio φ exceeds 2.9, the amount of smoke generated becomes visible to the naked eye.

Note that the equivalence ratio φ indicates how many times the amount of fuel is required at the stoichiometric air-fuel ratio, and has reciprocal information of the excess intake ratio λ. Therefore, the equivalence ratio φ at the stoichiometric air-fuel ratio is 1,
The richer the air-fuel ratio, the larger the value, and the leaner the air-fuel ratio, the smaller the value.

In addition, the air-fuel ratio and equivalence ratio of the injection port (ignition plug side intake port) in Fig. 30 above are (valve umbrella diameter), respectively.
It is calculated by finding the amount of intake air at the intake port from 2 x (valve lift) x (valve open period).

The present invention was created based on the inventor's knowledge as described above, and is designed to ensure that the local equivalence ratio supplied to the intake port on the spark plug side is less than or equal to the limit value set based on the smoke emission amount. An object of the present invention is to provide a fuel supply device for a stratified combustion internal combustion engine, which is capable of supplying fuel to a stratified combustion internal combustion engine.

[Means for solving the problem] For this reason, the fuel supply device for a stratified combustion internal combustion engine of the present invention (
Claim 1) is provided with at least two intake ports opening into the combustion chamber of the cylinder, and provided with a fuel supply means capable of supplying fuel to the intake port side according to the amount of intake air depending on the operating state, and An ignition plug is arranged at a position facing the combustion chamber that is biased from an intermediate position between the two intake ports toward one intake port, and the intake air drawn into the combustion chamber from each of the above intake ports during the engine intake stroke causes In a stratified combustion internal combustion engine configured to produce a tumble flow flowing in the direction of reciprocating movement of the piston, the local equivalence ratio in which the fuel supply means is supplied through one intake port near the ignition plug is equal to the smoke emission amount. It is characterized in that it is configured to supply fuel so that the fuel is below a limit value set based on.

Further, the fuel supply device (claim 2) for a stratified combustion internal combustion engine of the present invention is provided with at least two intake ports opening into the combustion chamber of the cylinder, and the amount of intake air to these two intake ports is adjusted according to the operating state. A fuel supply means capable of supplying fuel according to the engine intake stroke is provided, and an ignition plug is provided at a position facing the combustion chamber that is offset from an intermediate position between these two intake ports toward one of the intake ports, and In a stratified combustion internal combustion engine configured to generate a tumble flow flowing in the reciprocating direction of the piston by the intake air drawn into the combustion chamber from each of the above-mentioned intake ports, the fuel supply means is close to the spark plug. The amount of fuel supplied to one intake port is set to be greater than the amount of fuel supplied to the other intake port by the fuel supply means, and the local equivalence ratio supplied through the one intake port is set to be greater than the amount of fuel supplied to the other intake port by the fuel supply means, and the local equivalence ratio supplied through the one intake port The ratio of the amounts of fuel supplied from the fuel supply means to the two intake ports is set so as to be equal to or less than a limit value set based on the amount of fuel.

Furthermore, the fuel supply system for a stratified combustion internal combustion engine (Claim 3) of the present invention provides a fuel supply system for a stratified combustion internal combustion engine according to Claim 2, which provides a maximum total equivalence ratio necessary for output performance, and a fuel supply system for a stratified combustion internal combustion engine according to Claim 2 above. The fuel is supplied to the two intake ports at a ratio determined from the maximum allowable equivalence ratio of one intake port and the ratio of the amount of intake air flowing through each intake port.

Further, the fuel supply device (claim 4) for a stratified combustion internal combustion engine of the present invention is provided with at least two intake ports opening into the combustion chamber of the cylinder, and the amount of intake air to these two intake ports is adjusted according to the operating state. A fuel supply means capable of supplying fuel according to the engine intake stroke is provided, and an ignition plug is provided at a position facing the combustion chamber that is offset from an intermediate position between these two intake ports toward one of the intake ports, and In a stratified combustion internal combustion engine configured to generate a tumble flow flowing in the reciprocating direction of the piston by intake air drawn into the combustion chamber from each of the above intake ports, the intake air is supplied through one intake port near the ignition plug. control means is provided for controlling the amount of fuel supplied to the one intake port by the fuel supply means so that the local equivalence ratio obtained is equal to or less than a limit value set based on the smoke emission amount It is characterized by

Further, the fuel supply device for a stratified combustion internal combustion engine of the present invention (claim 5) is provided with two intake ports opening into the combustion chamber of the cylinder, and the amount of intake air to these two intake ports is adjusted according to the operating state. A fuel supply means capable of supplying the corresponding fuel is provided, and an ignition plug is provided at a position facing the combustion chamber that is offset from an intermediate position between these two intake ports toward one of the intake ports, and is provided with a fuel supply means capable of supplying fuel according to the engine intake stroke. In a stratified combustion internal combustion engine configured to generate a tumble flow flowing in the reciprocating direction of the piston by intake air drawn into the combustion chamber from each of the above intake ports, the intake air is supplied through one intake port near the ignition plug. control means is provided for controlling the amount of fuel supplied to the one intake port by the fuel supply means so that the local equivalence ratio obtained is equal to or less than a limit value set based on the smoke emission amount; If it becomes necessary to supply such a quantity of fuel to the combustion chamber that the local equivalence ratio supplied through the one intake port exceeds the limit value set based on the smoke emission amount, the other intake port It is characterized by the provision of auxiliary control means for replenishing the required amount of fuel through the port.

Further, the fuel supply device (claim 6) for a stratified combustion internal combustion engine of the present invention is provided with at least two intake ports opening into the combustion chamber of the cylinder, and the amount of intake air to these two intake ports is adjusted according to the operating state. A fuel supply means capable of supplying fuel according to the engine intake stroke is provided, and an ignition plug is provided at a position facing the combustion chamber that is offset from an intermediate position between these two intake ports toward one of the intake ports, and In a stratified combustion internal combustion engine configured to generate a tumble flow flowing in the reciprocating direction of the piston by intake air drawn into the combustion chamber from each of the above intake ports, the intake air is supplied through one intake port near the ignition plug. control means is provided for controlling the ratio of the amounts of fuel supplied to the two intake ports by the fuel supply means so that the local equivalence ratio obtained is less than or equal to a limit value set based on the smoke emission amount. It is characterized by

Further, in the fuel supply system for a stratified combustion internal combustion engine according to the present invention (claim 7), in the fuel supply system for a stratified combustion internal combustion engine according to claim 6, the local equivalence ratio supplied through the one intake port is If it is below the limit value set based on the smoke emission amount, the ratio of the amount of fuel supplied to the two intake ports is controlled to allow an increase or decrease in the amount of fuel supplied through the two intake ports. And the-
If it becomes necessary to supply such a quantity of fuel to the combustion chamber that the local equivalence ratio supplied through one intake port exceeds the above-mentioned limit value, the local equivalent ratio supplied through one intake port While supplying a fuel amount to the one intake port such that the ratio does not exceed the above limit value, calculate the ratio of the fuel amount supplied through the other intake port to the fuel amount supplied through the one intake port 1~. It is characterized in that the ratio of the amount of fuel supplied to the two intake ports is controlled so as to increase the amount of fuel supplied to the two intake ports.

[Function] In the above-described fuel supply system for a stratified combustion internal combustion engine of the present invention (claim 1), the local equivalence ratio supplied through one intake port near the ignition plug is set based on the smoke emission amount. Fuel is supplied from the fuel supply means so that the amount is below the limit value.

Further, in the fuel supply device for a stratified combustion internal combustion engine of the present invention (claim 2), more fuel is supplied from the fuel supply means to one intake port than to the other port, and through the one intake port. Fuel is supplied to the two intake ports at a ratio of fuel quantities such that the supplied local equivalence ratio is less than or equal to a limit value set based on the smoke emission amount.

At that time, fuel is supplied to the two intake ports at a ratio determined by the maximum total equivalence ratio required for output performance, the maximum allowable equivalence ratio of one intake port, and the ratio of the intake air amount flowing through each intake port. (Claim 3).

Further, in the fuel supply device for a stratified combustion internal combustion engine of the present invention (claim 4), the local equivalence ratio supplied through one intake port near the ignition plug is set by the control means based on the smoke emission amount. The amount of fuel supplied from the fuel supply means to one intake port is controlled so that the amount is equal to or less than the limit value.

Further, in the fuel supply system for a stratified combustion internal combustion engine according to the present invention (claim 5), the control means causes the local equivalence ratio supplied through one intake port to be equal to or less than a limit value set based on the smoke emission amount. The amount of fuel supplied from the fuel supply means to one intake port is controlled so that the local equivalence ratio supplied through one intake port is a limit value set based on the smoke emission amount. If it becomes necessary to supply a quantity of fuel to the combustion chamber that exceeds the quantity of fuel, the auxiliary control means replenishes the required quantity of fuel through the other intake port.

Further, in the fuel supply bag W for the stratified combustion internal combustion engine of the present invention (claim 6), the control means causes the local equivalence ratio supplied through one intake port to be equal to or less than a limit value set based on the smoke emission amount. The ratio of the amounts of fuel supplied from the fuel supply means to the two intake ports is controlled so that.

Furthermore, in the fuel supply bag M (claim 7) of the stratified combustion internal combustion engine of the present invention, when the control means controls the ratio of the amount of fuel supplied to the two intake ports, the fuel supply bag M is supplied through one intake port. If the local equivalence ratio determined is below a limit value set based on smoke emissions, then the fuel supplied to the two intake ports is adjusted to allow an increase or decrease in the amount of fuel supplied through the two intake ports. If it becomes necessary to control the fuel quantity ratio and supply a fuel quantity to the combustion chamber such that the local equivalence ratio supplied through one intake port exceeds the above limit value, The amount of fuel supplied through one intake port relative to the amount of fuel supplied through the other intake port, while supplying a quantity of fuel to one intake port such that the local equivalence ratio supplied does not exceed the above limit value. The ratio of fuel amounts supplied to the two intake ports is controlled so as to increase the ratio.

[Example] An example of the present invention will be described below with reference to one drawing.
1 to 4 show a fuel supply system for a stratified combustion internal combustion engine as a first embodiment of the present invention. The figure is a schematic plan view showing the overall configuration of a stratified combustion internal combustion engine having this device, FIG. 3 is a partial schematic plan view of a stratified combustion internal combustion engine having this device, and FIG. 4 is a control block diagram thereof. 5 to 12 show a fuel supply system for a stratified combustion internal combustion engine as a second embodiment of the present invention.
The figure is a perspective view of a combustion chamber in a stratified combustion internal combustion engine having this device, FIG. 6 is a schematic plan view showing the overall configuration of a stratified combustion internal combustion engine having this device, and FIG. 7 is a stratified combustion engine having this device. A partial schematic plan view of the internal combustion engine, FIG. 8 is its control block diagram, FIG. 9(a) is a plan view of the fuel injection valve, and FIG. 9(b) is the ub arrow in FIG. 9(a). View, 10th
The figures are schematic diagrams for explaining the procedure for calculating the nozzle diameter of the fuel injection valve, Figures 11 and 12 show modified examples of the fuel injection valve, and Figure 11 explains the arrangement of the fuel injection nozzle. FIG. 12 is a cross-sectional view of FIG. 11 as seen from the Kari-Kari arrow, and FIGS. 13 to 19 show a fuel supply system for a stratified combustion internal combustion engine as a third embodiment of the present invention. Fig. 13 is a transparent perspective view of a combustion chamber in a stratified combustion internal combustion engine having this device, Fig. 14 is a schematic plan view showing the overall configuration of a stratified combustion internal combustion engine having this device, and Fig. 15 has this device. A partial schematic plan view of a stratified combustion internal combustion engine, FIG. 16 is a plan view of a fuel injection valve, FIG. 17 is a view taken from the X■ arrow in FIG. 16, and FIG. 18 is a fuel injection port arrangement of a fuel injection valve. FIG. 19 is a schematic plan view showing an example in which fuel injection valves are arranged in a stratified combustion internal combustion engine in which spark plugs are arranged differently in adjacent cylinders; 20th-2nd
FIG. 5 shows a fuel supply device for a stratified combustion internal combustion engine as a fourth embodiment of the present invention, FIG. 20 is a transparent perspective view of a combustion chamber in a stratified combustion internal combustion engine having this device, and FIG. A schematic plan view showing the overall configuration of a stratified combustion internal combustion engine having this device, FIG. 22 is a plan view of a fuel injection valve, and FIG.
The figure is a view in the direction of the XXM arrow in FIG. 22, FIG. 24 is a view showing a modification of the fuel injection port arrangement of the fuel injection valve corresponding to FIG. 23, and FIG. 25 is a view in the direction of the XXV arrow in FIG. FIG. 26 is a schematic diagram for explaining the state of fuel injection as seen from the direction; FIG. 26 is a schematic plan view showing an example in which fuel injection valves are arranged in a stratified combustion internal combustion engine in which spark plugs are arranged differently in adjacent cylinders; FIG. figure(
a) and FIG. 27(b) are X X in FIG. 26, respectively.
FIG. 1 is a schematic diagram for explaining the state of fuel injection as seen from the direction of arrow Vlla and the direction of arrow xxvmb;
In Figures 28 and 27, the same reference numerals as in Figures 28 and 29 indicate substantially similar parts.

First, a first embodiment will be described using FIGS. 1 to 4. The stratified combustion internal combustion engine (engine) according to the first embodiment also has a four-cylinder gasoline engine 1, as shown in FIG.
Each cylinder 2 is provided with two independent intake ports 3 and 4 (intake valves not shown) having the same diameter, thereby forming a two-intake valve engine.

The intake ports 3 and 4 are connected to branch pipes 5a and 5b of an intake manifold 5, and the intake manifold 5 is connected to an intake pipe (not shown) via a throttle valve 6 from a surge tank 5c.

Furthermore, the intake ports 3 and 4 have their planar projection axes X,
Y is arranged so that it is substantially perpendicular to the diameter of the cylinder along the centerline CL of the engine, and the intake air is blown into the combustion chamber 7 obliquely downward with respect to the reciprocating direction of the piston 8. It has become.

Then, as shown in Figure 1.2.3, each intake port 3
.
An ignition plug 1° facing the combustion chamber 7 is provided in the cylinder head 2a near the open end.

Note that in the same operating state, one intake port 3 (hereinafter referred to as "one") closer to the ignition plug 1o from the fuel injection valve 91 is located.

The amount of fuel supplied from the fuel injection valve 92 to the other intake port 4 (sometimes referred to as "ignition plug side intake port 3") is
(hereinafter sometimes referred to as "non-spark plug side intake port 4").

That is, the spark plug side intake port 3 is configured as a rich side port, and the non-spark plug side intake port 4 is configured as a lean side port.

With this configuration, first, during the intake stroke of the engine 1, as the piston 8 descends, the mixture is sucked from the spark plug side intake port 3, and at the same time, air (or mixture) is sucked from the non-spark plug side port 4. and guided to the combustion chamber 7, respectively. At this time, fuel is injected from the fuel injection valve 91 into the spark plug side intake port 3 and a mixture of air and fuel is sucked into the combustion chamber 7, while the non-spark plug side intake port 4
Air only or fuel injection valve 92 as required
The mixture with the fuel injected further (hereinafter, this mixture will be referred to as a "lean mixture" as needed) is drawn in.

Each of the intake ports 3 and 4 has its respective planar projection axis X,
Since Y is substantially perpendicular to the diameter of the cylinder and located at symmetrical positions, most of the air-fuel mixture and air taken into the combustion chamber 7 are separated into layers along the reciprocating direction of the piston 8. The liquid flows in the form of so-called barrel swirls C and D (see Figure 1). Here, C is the barrel swirl of the mixture, and D is the barrel swirl of air or lean mixture.

In this way, the intake air taken into the combustion chamber 7 is compressed in the subsequent compression stroke, and then ignited by the ignition plug 10 installed near the open end of the intake port 3. (or lean mixture) swirls while separated, and the mixture burns stably.

In other words, if the air-fuel mixture supplied from the intake port 3 to the combustion chamber 1 is set to have a rich air-fuel ratio, the air-fuel mixture, together with the air (or lean mixture) supplied from the intake port 4, will have a lean air-fuel ratio as a whole. Even if the mixture is mixed, combustion will occur stably.

Such lean combustion has excellent anti-knock properties and contributes to improving fuel efficiency and CO emissions.

By the way, each fuel injection valve 9↓, 92 is subjected to electronic fuel control so that it can inject the amount of fuel according to the operating state of the engine, but for this purpose, as shown in FIG. Sensor 21. Engine load sensor 22. Engine temperature sensor 23. An acceleration sensor 24 is provided, as well as an electronic control unit (ECU) 25 that receives detection signals from these sensors 21 to 24 and controls the amount of fuel injected from each fuel injection valve 91,92.

Here, the engine speed sensor 21 detects the engine speed, and the engine load sensor 22 detects the engine load. As the engine load sensor 22, for example, an air flow sensor or a throttle sensor is used. .

Further, the engine temperature sensor 23 is for detecting engine temperature such as cooling water temperature, and the acceleration sensor 24 is for detecting an acceleration state, for example, a sensor for detecting a change in throttle opening is used.

As mentioned above, the present inventor discovered that if the equivalence ratio φ of the air-fuel mixture on the ignition side (that is, on the ignition plug side intake port 3 side) is too rich,
Through experiments, we learned that this is one of the causes of smoke generation. That is, through experiments, it was found that the relationship between the equivalence ratio φ (or air-fuel ratio) at the spark plug side intake port 3 and the smoke emission amount is as shown in Fig. 30. It was found that the amount of smoke generated begins to increase when the ratio φ exceeds 2.1, and furthermore, it was found that when the equivalence ratio φ exceeds 2.9, the amount of smoke generated becomes visible to the naked eye. It is.

Based on the inventor's knowledge, in this embodiment, the local (local) equivalence ratio φ supplied to the intake port 3 on the side of the ignition plug 10 is set to a limit value ( In this example, the amount of fuel injected from the fuel injection valve 91 is controlled so that the amount of fuel is 2.9 (preferably 2.1) or less.

Therefore, the E CU 25 uses the local equivalence ratio φ supplied through the ignition plug side intake port 3 in almost the entire operating range (however, special conditions such as warm-up operation may be excluded).
It has the function of a control means for controlling the amount of fuel supplied to the intake port 3 by the fuel injection valves 91 and 92 so that the amount of fuel is equal to or less than the above-mentioned limit value set based on the smoke emission amount.

In addition, in order to secure engine output during acceleration, etc., it becomes necessary to supply an amount of fuel to the combustion chamber 7 such that the local equivalence ratio φ supplied through the intake port 3 exceeds the above-mentioned limit value. In consideration of the case, the ECU 25 of this embodiment is configured such that if it becomes necessary to supply the amount of fuel to the combustion chamber 7 such that the local equivalence ratio φ supplied through the intake port 3 exceeds the above-mentioned limit value, , a fuel injection valve 9 to replenish the required amount of fuel through the other intake port 4.
It also has the function of an auxiliary control means for controlling the amount of fuel injected from 2.

As a result, while the local equivalence ratio φ supplied through the ignition plug side intake port 3 is suppressed to below the above-mentioned limit value set based on the smoke emission amount, the overall fuel amount exceeds the above-mentioned limit value. It can be supplied to the combustion chamber 7. As a result, under any operating condition, sufficient acceleration and the like can be performed while the amount of smoke emissions is sufficiently suppressed. In other words, in this embodiment, while achieving lean burn through barrel strategy in all operating ranges, it is possible to sufficiently suppress smoke emissions that may occur outside the lean combustion range.

In addition, under special conditions such as warm-up operation, the fuel injection valve 91.9 is operated so that the local equivalence ratio φ supplied through the ignition plug side intake port 3 is below the above-mentioned limit value.
In some cases, the fuel amount control for No. 2 may be canceled.

In addition, the ECU 25 controls each fuel injection valve 91,92 so as to achieve the required air-fuel ratio by supplying fuel according to the amount of intake air according to the operating state of the engine, which has been conventionally done. Needless to say, it has control means (so-called air-fuel ratio control means).

Further, fuel is always injected from each fuel injection valve 91, 92, but the local equivalence ratio φ supplied through the spark plug side intake bows 1 to 3 is set based on the smoke emission amount. The ratio F, :F, of the amount of fuel supplied to each intake port 3, 4 by each fuel injection valve 91, 92 may be controlled so that it is below a limit value.

In this case, the fuel is supplied to the respective intake ports 3 and 4 by the respective fuel injection valves 91 and 92 so that the local equivalence ratio φ supplied to the ECU 25 through the ignition plug side intake port 3 is equal to or less than the above-mentioned limit value. Ratio of fuel amount F□:F
It has the function of a control means for controlling 2.

Here, a method of determining the ratio F:F2 of the amount of fuel such that the local equivalence ratio φ supplied through the ignition plug side intake port 3 is equal to or less than the above-mentioned limit value will be explained.

First, since the smoke emission amount shown in Figure 30 differs depending on the engine model, we obtained the data shown in Figure 30 through an actual machine test, and based on the data obtained, we determined that the allowable maximum equivalent of injection port 1- (ignition plug side intake port 3) After determining the ratio φwax, the above ratio is obtained using the following formula.

Now, the total maximum equivalence ratio per cylinder φ7max (constant), the maximum allowable equivalence ratio φl1 of the injection port (ignition plug side suction port 3) determined from the data obtained from the actual machine test
lax (constant), air iA flowing through each intake port 3, 4
1. A, [A1 is for the intake port (rich port) 3 on the spark plug side, lA2 is for the intake port (lean port) 4 on the non-spark plug side], the amount of fuel injected into each intake port 3, 4 F1. F2 [F□ is the intake port on the spark plug side (
F2 is that of the intake port (lean port) 4 on the non-ignition plug side], the equivalence ratio φL of the intake port 4 on the lean side, the allowable maximum equivalence ratio φmax, and each intake port 3, The following equation is calculated as the total fuel amount FT determined from the air amount A□ flowing through 4 and A2.

F2=FT-F□...(1) A1:F, (14,7/+may)"(2) A2=F2
(14,7/sL)...(3) From equations (1) and (3), A2=(FT-F)(14,7/lt)...(4)(
From equations 2) and (4), F, (14,7hamax)”(Ax/Az)(Fr-
Fx) (14,7/φL)・(5) Also, (14,7/φrmax)=(Ax+Az)/(Fx+
Fz)=(Fl(14,7han+ax)+(F7-F□
)(14,7/suL))/(F,+(FT-Fl))・
・(6) Substitute equation (6) into equation (5), (14,7/φ7max)=(F, (14,7/φw)
ax)+(A, /AX)F, (14,7hamax))
/Fr...(7) From equation (7), F□=(1s+ax/17max)[F7/(14(A
, /A, )) (8) From equations (8) and (1), Fz:Fr(1-a)...(9) Here, direct = (φmax/hmax) [1/(1+ (A
x/Ax))].

From the above equations (8) and (9), Fl: F, = ++: 1-ku = ($max/◆Tmax) [1/(1+(A2/A,
))]:1-($max/ψrmax)[1/(1+(
A2/A,))]" (10) As described above, the maximum total equivalence ratio φ7fflaX necessary for output performance, the maximum allowable equivalence ratio φwax of the spark plug side intake port 3, and the intake flowing through each intake port 3 and 4. The fuel injection amount ratio F1:F2 to each intake port 3.4 can be determined from the air amount ratio (A2/A).

The ECU 25 controls the ratio of fuel injected from each fuel injection valve 91, 92 to each intake port 3, 4 to the above ratio F1:F.

In this way, even at the maximum injection amount, the local equivalence ratio φ supplied through the rich side port 3 will be equal to or less than the above-mentioned limit value, so that the occurrence of smoke can be reliably suppressed.

Furthermore, by supplying fuel only from the spark plug side intake port 3 and supplying only air from the non-spark plug side intake port 4, good anti-knock properties can be obtained without complete stratification, and fuel efficiency and CO It has been confirmed that sufficient effects can be obtained in improving emissions.

Also, as mentioned above, the ECU 25 may control the ratio of fuel injected from each fuel injection valve 91, 92 to each intake port 3, 4 so that it always becomes the constant ratio F□:F2. If the local equivalence ratio φ supplied through one intake port 3 is less than or equal to the above-mentioned limit value set based on the smoke emission amount, then the two intake ports 3,
4 to allow for an increase or decrease in the amount of fuel supplied through
Controls the ratio of the amounts of fuel supplied to the two intake ports 3 and 4, and supplies the amount of fuel to the combustion chamber 7 such that the local equivalence ratio φ supplied through one intake port 3 exceeds the above limit value. If the need arises, the spark plug side intake air is supplied to the spark plug side intake port 3 while supplying an amount of fuel such that the local equivalence ratio supplied through the spark plug side intake port 3 does not exceed the above limit value. The ratio of the amount of fuel supplied to the two intake ports 3 and 4 is controlled so as to increase the ratio of the amount of fuel supplied through the non-spark plug side intake port 4 to the amount of fuel supplied through the port 3. You can.

Note that the fuel injection valve 92 is not provided, and only the fuel injection valve 91 is provided in the ignition plug side intake port 3, so that the fuel injection valve 92 is not provided, and only the fuel injection valve 91 is provided in the ignition plug side intake port 3, and in almost the entire operating range (however, special conditions such as warm-up operation may be excluded). The fuel injection valve 9
1 may be used to control the amount of fuel supplied to the intake port 3.

Next, a second embodiment will be described using FIGS. 5 to 12. The stratified combustion internal combustion engine (engine) according to the second embodiment is also a four-cylinder gasoline engine 1, as shown in FIG. The ends merge into a branch pipe 5a of the intake manifold 5.
(In other words, these intake ports 1 to 3 and 4 are not independent ports like the intake ports 3 and 4 in the first embodiment described above.)
are provided, and furthermore, these two intake ports 3,
4 are arranged so that the planar projection axes of these intake ports 3 and 4 are both orthogonal to the diameter of the cylinder 2. Note that illustration of the intake valve provided at each intake port is omitted.

Thereby, a tumble flow that flows in the reciprocating direction of the piston 8 can be generated by the intake air sucked into the combustion chamber 7 from each intake port 3.4 during the engine intake stroke.

In addition, two lines of fuel can be supplied to the two intake ports 3 and 4 according to the amount of intake air corresponding to the operating condition (see Fig. 9).
A multi-spray type fuel injection valve (fuel supply means) 93 as shown in a) and (b) is provided, and the combustion is biased from an intermediate position between these two intake ports 3° 4 to one intake port 3 side. An ignition plug 10 is disposed at a position facing the chamber 7, and the above-mentioned fuel injection valve 93 is shown in FIG.
It has an external shape as shown in a), and is arranged so that its tip faces near the branching part P of the intake ports 3 and 4 (see Figures 5 to 7), and furthermore, as shown in Figure 9 ( As shown in b), it is equipped with two large and small fuel injection ports 931, 932 (these fuel injection ports 931, 932 are circular), and the fuel from the fuel injection port 931 having a large injection port area is The fuel is injected into the intake port 3 on the spark plug side, and fuel from the other fuel injection port 932 having a small nozzle area is injected into the intake port 4 on the non-spark plug side.

As a result, the amounts of fuel injected into the two intake ports 3 and 4 through these fuel injection ports 931 and 932 are set to be different. That is, the amount of fuel injected into the spark plug side intake port 3 is greater than the amount of fuel injected into the other intake ports 4.

In this case, fuel is supplied from the fuel injection valve 93 to the two intake ports 3 and 4 so that the local equivalence ratio φ supplied through the intake port 3 is equal to or less than the above-mentioned limit value set based on the amount of smoke discharged. The fuel quantity ratio is set, and in this case, the maximum total equivalence ratio φ7max required for output performance and the maximum allowable equivalence ratio φm of the intake port 3
ax and the ratio of the amount of intake air flowing through each intake port 3 and 4 (
Fuel is supplied to the two intake ports 3 and 4 at a constant ratio F1:F, which is determined from A2/A (for this ratio, see equation (10) above).

By the way, as mentioned above, a constant ratio (
In order to supply fuel with Fl:F2), the ratio of each fuel injection diameter is set as follows.

First, the following formula holds.

trl”/F□=zr2”/F2” (11) Here, r
l is the radius of the fuel injection port 931, F2 is the fuel injection port 932
is the radius of

Transforming this equation (11), rt"(Fx/F2)""rz"(tz) Therefore, r,:r2=(F,/F2)"":1=(a/(1-a
))””:1...(13) Here, g=0max/
17max) [1/(1+(A-/Ax)).

That is, the ratio (rx:
rz) is set as shown in equation (13) above.

As can be seen from equation (13), the ratio (rt:rz) of the fuel injection port diameter of the fuel injection valve 93 is determined by the maximum total equivalence ratio φ7maN required for output performance and the maximum allowable value of one intake port 3. It is determined from the equivalence ratio φff1ax and the ratio (A2/A1) of the amount of intake air flowing through each intake port 3, 4. Furthermore, as can be seen from Fig. 10, φT
maK is the sum of φwax and φL.

In this way, the ratio of the fuel injection diameter of the fuel injection valve 93 is set to r□:
By setting F2 (constant), the local equivalence ratio φ supplied through the intake port 3 can always be kept below the above-mentioned limit value set based on the smoke emission amount.

Therefore, the fuel injection valve 9 as shown in this second embodiment
3, while still using one fuel injector for each cylinder as before.

Moreover, in the entire operating range without using complicated moving mechanisms,
It is possible to achieve lean burn through barrel stratify, which reduces fuel consumption and CO emissions, and also sufficiently reduces smoke emissions that may occur under operating conditions that do not use lean combustion (such as sudden acceleration). This can be suppressed to

In addition, by using the multi-spray fuel injection valve 93 having large and small fuel injection ports 931 and 932 to perform constant face port injection with one fuel injection valve for each cylinder, it is possible to perform continuous face port injection using one fuel injection valve for each cylinder. A separate intake system for the burn engine (see Figures 28 and 29) can be dispensed with. The reason why an independent intake system can be made unnecessary is as follows. In other words, in the past, the aim was to achieve complete stratification in the lean combustion range, so each intake port was made into an independent intake system in order to avoid fuel flowing into the non-ignition side port 4 due to intake air blowback, etc. However, subsequent research This is because the sufficient effects of stratified combustion could be obtained even if complete stratification was not achieved.

In addition, as shown in Figure 11.12, there are a total of three fuel injection ports located at each vertex of the triangle (numerals 941, 9).
42,943) and three fuel injection ports 941~
Fuel from two fuel injection ports 941 and 942 among the three fuel injection ports 941 and 943 is injected into the spark plug side intake port 3, and fuel from one fuel injection port 943 among the three fuel injection ports 941 to 943 is injected to the other fuel injection port 943. The attachment position of the fuel injection valve 94 to the intake system is set so that the fuel injection valve 94 is injected into the intake port 4, and the fuel injection valve 94 is injected from two fuel injection ports 941 and 94.2 among these three fuel injection ports 941 to 943. The above two fuel injection ports 941 and 942 may be formed so that the fuel is merged after injection and is injected into the spark plug side intake port 3.

In this case, it goes without saying that the ratio between the total amount of fuel from the two fuel injection ports 941 and 942 and the amount of fuel from the remaining one fuel injection port 943 is set to F2 as described above. Nor.

By doing so, in addition to obtaining almost the same effects or advantages as using the above-mentioned fuel injection valve 93,
Since the fuel is merged after the fuel is injected, the atomization of the spray can be achieved, which has the advantage of improving combustion performance.

Note that the fuel injection valves 93, 94 are connected to the engine rotation speed sensor 21.94, as shown in FIG. Engine load sensor 2
2. Engine temperature sensor 23. An ECU 25' receives a detection signal from the acceleration sensor 24 and controls the amount of fuel injected from the fuel injection valves 93 and 94 [This ECU 25' is supplied with fuel according to the amount of intake air depending on the operating state of the engine. The fuel injector 93 is controlled by means (so-called air-fuel ratio control means) so as to achieve the required air-fuel ratio, and thereby the fuel is injected according to the operating state of the engine. Electronic fuel supply control is now performed, but the details of this electronic control will be omitted since it is the same as before.

Next, a third embodiment will be described using FIGS. 13 to 19.

Stratified combustion internal combustion engine (engine) according to this third embodiment
Also, as shown in Fig. 14, a four-cylinder gasoline engine 1
As in the second embodiment, each cylinder 2 has an intake port 3.4 (intake valves not shown) of equal diameter whose base ends meet and are connected to a branch pipe 5a of the intake manifold 5. Furthermore, these two intake ports 3 and 4 are arranged so that the planar projection axes of these intake ports 3 and 4 are both substantially perpendicular to the diameter of the cylinder 2.

Thereby, a tumble flow that flows in the reciprocating direction of the piston 8 can be generated by the intake air sucked into the combustion chamber 7 from each intake port 3.4 during the engine intake stroke.

In addition, a multi-spray fuel injection valve (fuel injection valve) as shown in Fig. 16.17 can supply a total of three lines of fuel to these two intake ports 3 and 4 according to the amount of intake air depending on the operating condition. A spark plug 10 is provided at a position facing the combustion chamber 7 which is offset from the intermediate position between these two intake ports 3.4 toward one intake port 3.
However, the above fuel injection valve 95 is the 16th
It has an external shape as shown in the figure, and is arranged so that its tip faces near the branch P of the intake ports 3 and 4 (
(see Figures 13 to 15), and further as shown in Figure 17,
Three fuel injection ports 951, 95 with equal nozzle area
2,953 (all of these fuel injection ports 951 to 953 are circular) are arranged on a straight line.

Then, fuel from two fuel injection ports 951 and 952 among these three fuel injection ports 951 to 953 is injected to the spark plug side intake port 3, and fuel from the remaining one fuel injection port 953 is injected to the other fuel injection port 951. In order to inject fuel into the intake port 4, the fuel injection valve 95 is installed at an angle θ relative to the direction toward the branch point P of the intake ports 3 and 4 (see FIGS. 13 to 15).

As a result, the two fuel injection ports 951 of the fuel injection valve 95
, 952 is injected into the intake port 3 on the spark plug side, and fuel from the remaining one fuel injection port 953 is injected into the intake port 4 on the non-spark plug side. As a result, the amount of fuel injected into the spark plug side intake port 3 becomes larger than the amount of fuel injected into the non-spark plug side intake port 4.

In this case, normally the maximum total equivalence ratio φ7max required for output performance, the allowable maximum equivalence ratio φmax of the spark plug side intake port 3, and the ratio of the amount of intake air flowing through each intake port 3 and 4 (A2/A□ ) has the required relationship, so the local equivalence ratio φ supplied through the intake port 3
Fuel can be supplied from the fuel injection valve 95 to the two intake ports 3 and 4 such that the amount of fuel is equal to or less than the above-mentioned limit value set based on the amount of smoke discharged.

Further, as shown in FIG. 18, the nozzle area of the fuel nozzle 952' arranged in the middle among the three fuel nozzles 951, 952', 953 arranged linearly is the nozzle area of the other fuel nozzles 951, 952', 953. If the nozzle area is made different from the nozzle area of 953 (larger in this example), the maximum total equivalence ratio φ7max required for output performance, the allowable maximum equivalence ratio φwax of the ignition plug side intake port 3, and each intake port 3 , 4 (A2/A): F2 [For this ratio, refer to equation (10) above], the fuel is supplied to the two intake ports 3 and 4. The supply can be adjusted accordingly.

In addition, in addition to the case in which the nozzle area of the fuel injection port 952' arranged in the middle among the three fuel injection ports 951 to 953 is configured to be different from the nozzle area of the other fuel injection ports 951 and 953, The nozzle area of one of the fuel injection ports disposed at both ends of the ports 95 to 953 may be configured to be different from the nozzle area of the other fuel injection ports, and the three fuel injection ports 951 to The nozzle areas of the 953 may be configured to be different from each other.

In this way, fuel can be supplied to the two intake ports 3 and 4 at exactly the above-mentioned constant ratio F1:F2, so that the local equivalent amount supplied through the spark plug side intake port 3 is effectively reduced. The ratio φ can always be kept below the above limit value.

Therefore, the fuel injection valve 9 as shown in this third embodiment
By using No. 5, the same effects and advantages as those of the second embodiment described above can be obtained.

In other words, while using one fuel injector for each cylinder as before, without the use of complex moving mechanisms, lean burn is achieved through barrel stratification in the entire operating range, resulting in improved fuel efficiency and CO emissions. In addition to reducing the amount of fuel, it is also possible to reduce the
It is also possible to sufficiently suppress smoke emissions that may occur during sudden acceleration (such as sudden acceleration).

In addition, by using the three-line multi-spray fuel injection valve 95 to constantly perform both port injection with one fuel injection valve for each cylinder, an independent intake system for a conventional lean-burn engine using barrel swirl can be used. can be made unnecessary.

Note that, like the fuel injection valves 93 and 94 according to the second embodiment described above, this fuel injection valve 95 is also connected to the engine rotation speed sensor 21. Engine load sensor 22° engine temperature sensor 23. ECU 25' which receives a detection signal from acceleration sensor 24 and controls the amount of fuel injected from fuel injection valve 95;
Needless to say, it is controlled by (see Fig. 8).

By the way, if the fuel injection valve 95 according to the third embodiment shown in FIGS. 16 and 17 is used, it can also be applied to an engine (stratified combustion internal combustion engine) in which the shapes of adjacent cylinders 2 are bilaterally symmetrical, as shown in FIG. 19. By changing the mounting angle of the fuel injection valve 95 to be symmetrical, the fuel injection valve 95 can be easily mounted. That is, one fuel injection valve 95 is installed by swinging it to the right by 0, and the other fuel injection valve 95 is installed by swinging it by 0 to the right.

Next, a fourth embodiment will be described using FIGS. 20 to 27.

Stratified combustion internal combustion engine (engine) according to this fourth embodiment
Also, as shown in Fig. 21, a four-cylinder gasoline engine 1
Similarly to the second and third embodiments, each cylinder 2 has intake ports 1 to 3 and 4 of equal diameter (intake valves are not shown) whose base ends meet and are connected to a branch pipe 5a of an intake manifold 5. ) are provided, and these two intake ports 3 and 4 are
These intake ports 3 and 4 are arranged so that their planar projection axes are substantially orthogonal to the diameter of the cylinder 2.

Thereby, a tumble flow that flows in the reciprocating direction of the piston 8 can be generated by the intake air sucked into the combustion chamber 7 from each intake port 3.4 during the engine intake stroke.

In addition, a multi-spray fuel injection valve (fuel injection valve) as shown in Fig. 22 and 23 can supply a total of three lines of fuel to these two intake ports 3 and 4 according to the amount of intake air depending on the operating condition. A spark plug 10 is provided at a position facing the combustion chamber 7 which is biased toward one intake port 3 from an intermediate position between these two intake ports 3.4.
However, the above fuel injection valve 96 is the 22nd
It has an external shape as shown in the figure, and is arranged so that its tip faces near the branching part P of the intake ports 3 and 4 (
(see Figure 20.21), and further as shown in Figure 23,
Three fuel injection ports 961, 96 with equal nozzle area
2,963 (all of these fuel injection ports 961 to 963 are circular) are arranged to be located at each vertex of the triangle.

Then, fuel from two fuel injection ports 961 and 962 among these three fuel injection ports 961 to 963 is injected to the spark plug side intake port 3, and fuel from the remaining t fuel injection ports 963 is injected to the other fuel injection port 961. The fuel injection valve 96 is mounted at a position rotated by η around its central axis from its normal position so that fuel is injected into the intake port 4 (see FIG. 23).

As a result, as shown in FIG. 25, fuel from the two fuel injection ports 961 and 962 of the fuel injection valve 96 is injected into the spark plug side intake port 3, and fuel is injected from the remaining one fuel injection port 963. is injected into the intake port 4 on the non-spark plug side. As a result, the amount of fuel injected into the spark plug side intake port 3 becomes larger than the amount of fuel injected into the non-spark plug side intake ports 1 to 4.

In this case as well, normally the highest total equivalence ratio φ7+118X required for output performance, spark plug side intake port 3
Since the allowable maximum equivalence ratio φmax of Fuel can be supplied from the fuel injection valve 96 to the two intake ports 3 and 4 so that the amount is equal to or less than a limit value set based on the exhaust amount.

Further, as shown in FIG. 24, the nozzle area of one fuel nozzle 962' of the three fuel nozzles 961, 962', and 963 arranged at each vertex of the triangle is the area of the other fuel nozzle 961. , 963 (larger in this example), the maximum total equivalence ratio φ7max required for output performance, the maximum allowable equivalence ratio φwax of the spark plug side intake port 3, and each intake port. A fixed ratio F1:F2 determined from the ratio of the amount of intake air flowing through ports 3 and 4 (A2/A) [For this ratio, refer to equation (10) above. The supply can be adjusted accordingly.

In addition, the nozzle area of the fuel nozzle 961 or 962 among the three fuel nozzles 961 to 963 may be configured to be different from the nozzle area of the other fuel nozzles. The nozzle areas may be configured to be different from each other.

In this way, fuel can be supplied to the two intake ports 3 and 4 at exactly the above-mentioned constant ratio F:F2, so that the local equivalence ratio φ supplied through the intake port 3 is effectively can always be kept below the above limit value.

Therefore, the fuel injection valve 9 as shown in this fourth embodiment
6, the same effects and advantages as those of the above-mentioned 2.3 embodiment can be obtained.

In other words, while using one fuel injector for each cylinder as in the past, and without using a complicated moving mechanism, lean burn is achieved through barrel stratification in the entire operating range, resulting in improved fuel efficiency and C○. Not only can emissions be reduced, but also under operating conditions that do not use lean combustion (
It is also possible to sufficiently suppress smoke emissions that may occur during sudden acceleration (such as sudden acceleration).

In addition, by using this three-line multi-spray fuel injection valve 96 and performing constant face port injection with one fuel injection valve for each cylinder, an independent intake system for a conventional lean-burn engine using barrel swirl can be used. can be made unnecessary.

Note that this fuel injection valve 96 is also connected to the engine rotation speed sensor 21, similar to the fuel injection valves 93, 94; Engine load sensor 22. Engine temperature sensor 23. EC that controls the amount of fuel injected from the fuel injection valve 93 in response to a detection signal from the acceleration sensor 24;
Needless to say, it is controlled by U25' (see FIG. 8).

By the way, even when the fuel injection valve 96 according to the fourth embodiment shown in FIGS. 22 to 24 is used, it will not work in an engine (stratified combustion internal combustion engine) in which the shapes of adjacent cylinders 2 are bilaterally symmetrical as shown in FIG. 26. The fuel injection valve 96 can also be easily installed by changing the installation rotation angle of the fuel injection valve 96 to be symmetrical. That is, one fuel injection valve 96 is installed after being rotated by η to the right from its normal position, and the other fuel injection valve 96 is installed after being rotated from its normal position by η to the left [23rd degree]. 24,. 27
See Figures (a) and (b)].

As a result, for adjacent cylinders, in one cylinder,
The fuel from the two fuel injection valves 96 [1961 and 962 is injected into the spark plug side intake port 3, and the fuel from the remaining one fuel injection port 963 is injected into the non-spark plug side intake port 4. [
Referring to FIG. 27(a), in the other cylinder, fuel from the two fuel injection ports 962 and 963 of the fuel injection valve 96 is injected into the spark plug side intake port 3, and the remaining one fuel injection port 961 can be injected into the intake port 4 on the non-spark plug side [27th
See figure (b).

Although each of the above embodiments describes a stratified combustion internal combustion engine with two intake ports, the same applies to a spark ignition multi-valve type stratified combustion internal combustion engine with three or more intake ports. I can do it.

In addition, in the above-mentioned second to fourth embodiments, explanations have been given of those having two or three fuel injection ports, but the present invention can be similarly applied to those having four or more fuel injection ports. can.

[Effects of the Invention] As detailed above, according to the fuel supply system for a stratified combustion internal combustion engine of the present invention, in a stratified combustion internal combustion engine, the local equivalence ratio supplied through one intake port near the ignition plug is The fuel supply means is configured to supply fuel so that the amount is below a limit value set based on the smoke emission amount (Claim 1), or the fuel supply means is configured to supply fuel to one intake port near the ignition plug. quantity is set to be greater than the quantity of fuel supplied to the other intake port, and such that the local equivalence ratio supplied through one intake port is less than or equal to a limit value set based on the smoke emission quantity. The ratio of the amount of fuel supplied from the fuel supply means to the two intake ports (for example, as described in claim 3, the maximum total equivalence ratio necessary for output performance, the maximum allowable equivalence ratio of one intake port, and each (Claim 2) The local equivalence ratio supplied through one intake port near the ignition plug is set based on the amount of smoke discharged. A control means is provided for controlling the amount of fuel supplied to one intake port by the fuel supply means so that the amount of fuel is below a limit value (Claim 4), and the local equivalence ratio supplied through one intake port is smoked. When it becomes necessary to supply the combustion chamber with an amount of fuel that exceeds the limit value set based on the exhaust amount, the control means provides an auxiliary control means for replenishing the necessary amount of fuel through the other intake port. In addition to (
Claim 5) The fuel is supplied to the two intake ports by the fuel supply means such that the local equivalence ratio supplied through the one intake port near the spark plug is less than or equal to a limit value set based on the smoke emission amount. control means for controlling the ratio of the amount of fuel (for example, as described in claim 7, if the local equivalence ratio supplied through one intake port is less than a limit value set based on the smoke emission amount,
The ratio of the amount of fuel supplied to the two intake ports is controlled to allow an increase or decrease in the amount of fuel supplied through the two intake ports, and the local equivalence ratio supplied through one intake port is set to the above limit. If it becomes necessary to supply a quantity of fuel to the combustion chamber that exceeds the limit value, the quantity of fuel supplied through one intake port is such that the local equivalence ratio supplied through one intake port does not exceed the limit value indicated in 2. The ratio of the amount of fuel supplied to the two intake ports, while supplying the two intake ports, so as to increase the ratio of the amount of fuel supplied through one intake port to the amount of fuel supplied through the other intake port. (Claim 6), it is possible to achieve lean burn by barrel stratify, reduce fuel consumption and CO emissions, and reduce CO emissions outside the lean combustion range. This has the advantage of sufficiently suppressing smoke emissions that may otherwise occur.

[Brief explanation of drawings]

1 to 4 show a fuel supply system for a stratified combustion internal combustion engine as a first embodiment of the present invention. The figure is a schematic plan view showing the overall configuration of a stratified combustion internal combustion engine having this device, FIG. 3 is a partial schematic plan view of a stratified combustion internal combustion engine having this device, and FIG. 4 is a control block diagram thereof. 5 to 12 show a fuel supply system for a stratified combustion internal combustion engine as a second embodiment of the present invention.
The figure is a perspective view of a combustion chamber in a stratified combustion internal combustion engine having this device, FIG. 6 is a schematic plan view showing the overall configuration of a stratified combustion internal combustion engine having this device, and FIG. 7 is a stratified combustion engine having this device. A partial schematic plan view of the internal combustion engine, FIG. 8 is a control block diagram thereof, FIG. 9(a) is a plan view of the fuel injection valve, and FIG. 9(b) is a partial schematic plan view of the internal combustion engine. Arrow view, 10th
The figures are schematic diagrams for explaining the procedure for calculating the nozzle diameter of the fuel injection valve, Figures 11 and 12 show modified examples of the fuel injection valve, and Figure 11 explains the arrangement of the fuel injection nozzle. Fig. 12 is a cross-sectional view of Fig. 1 in the curvature direction, and Figs. 13 to 19 show a fuel supply system for a stratified combustion internal combustion engine as a third embodiment of the present invention. , FIG. 13 is a transparent perspective view of a combustion chamber in a stratified combustion internal combustion engine having this device, FIG. 14 is a schematic plan view showing the overall configuration of a stratified combustion internal combustion engine having this device, and FIG. 15 is a perspective view of a combustion chamber in a stratified combustion internal combustion engine having this device. FIG. 16 is a plan view of a fuel injection valve, FIG. 17 is a view taken in the direction of the X arrow in FIG. 16, and FIG. 18 is a fuel injection port of the fuel injection valve. 19 is a diagram showing a modification of the arrangement in correspondence with FIG. 17, and FIG. 19 is a schematic plan view showing an example in which fuel injection valves are arranged in a stratified combustion internal combustion engine with different spark plug arrangements in adjacent cylinders. , No. 20-2
5 shows a fuel supply device for a stratified combustion internal combustion engine as a fourth embodiment of the present invention, FIG. 20 is a transparent perspective view of a combustion chamber in a stratified combustion internal combustion engine having this device, and FIG.
The figure is a schematic plan view showing the overall configuration of a stratified combustion internal combustion engine having this device, FIG. 22 is a plan view of a fuel injection valve, and FIG.
24 is a view showing a modification of the fuel injection port arrangement of the fuel injection valve corresponding to FIG. 23, and FIG. 25 is a view taken along the XXv arrow in FIG. 20. FIG. 26 is a schematic diagram for explaining the state of fuel injection as seen from the visual direction, and FIG. Figure 27 (
a) and FIG. 27(b) are X X in FIG. 26, respectively.
FIG. 28 is a schematic diagram for explaining the state of fuel injection as seen from the direction of the arrow VI[a and the direction of the xxvub arrow;
．． Figure 29 shows a conventional stratified combustion internal combustion engine.
Figure 8 is a schematic plan view showing its overall configuration, Figure 29 is a perspective view of its combustion chamber, and Figure 30 shows the relationship between the equivalence ratio (air-fuel ratio) of the ignition plug side intake port and the amount of smoke discharged. This is a graph for explaining. 1- Engine, 2... Cylinder, 2a... Cylinder head, 3...- Spark plug side intake port (one intake port) 4...- Non-spark plug side intake port (other intake port)
, 5--Intake manifold, 5a, 5b... Branch pipe, 5C-- Surge tank, 6- Throttle valve, 7
・～・Combustion chamber, 8...-piston, 9-fuel injection valve, 1
0...Spark plug, 2 Ni-engine speed sensor, 22
--Engine load sensor, 23--Engine temperature sensor, 24-Acceleration sensor, 25--ECU having the functions of control means and auxiliary control means, 25'--ECU
, 91-96-Fuel injection valve (fuel supply means), 931.
932,941~943,951~953°952',
961~963,962'---Fuel injection port, X, Y・
- plane projection axis of the intake port;

Claims (7)

[Claims] (1) Provided with at least two intake ports opening into the combustion chamber of the cylinder, provided with a fuel supply means capable of supplying fuel to the intake port side according to the amount of intake air depending on the operating condition, and An ignition plug is disposed at a position facing the combustion chamber that is biased from the intermediate position of the port toward one intake port, and the piston is reciprocated by the intake air sucked into the combustion chamber from each intake port during the engine intake stroke. In a stratified combustion internal combustion engine configured to produce a tumble flow flowing in the direction of movement, the fuel supply means is configured to provide a fuel supply means with a local equivalence ratio supplied through one intake port near the spark plug based on smoke emissions. 1. A fuel supply device for a stratified combustion internal combustion engine, characterized in that the fuel supply device is configured to supply fuel so that the fuel is at or below a set limit value. (2) Provided with at least two intake ports opening into the combustion chamber of the cylinder, and provided with fuel supply means capable of supplying fuel to both of these two intake ports in accordance with the amount of intake air depending on the operating state, and An ignition plug is arranged at a position facing the combustion chamber that is biased from an intermediate position between the two intake ports to one intake port side, and during the engine intake stroke, the intake air drawn into the combustion chamber from each intake port causes the piston In a stratified combustion internal combustion engine configured to generate a tumble flow flowing in the reciprocating direction of The fuel supply is set to be greater than the amount of fuel supplied to the port, and such that the local equivalence ratio supplied through the one intake port is less than or equal to a limit value set based on smoke emissions. A fuel supply device for a stratified combustion internal combustion engine, characterized in that a ratio of fuel amounts supplied from the means to the two intake ports is set. (3) Fuel flows to the two intake ports at a ratio determined by the maximum total equivalence ratio required for output performance, the maximum allowable equivalence ratio for one of the intake ports, and the ratio of the amount of intake air flowing through each intake port. 3. The fuel supply system for a stratified combustion internal combustion engine according to claim 2, wherein the fuel supply system is supplied with fuel for a stratified combustion internal combustion engine. (4) Provided with at least two intake ports opening into the combustion chamber of the cylinder, and provided with fuel supply means capable of supplying fuel to both of these two intake ports in accordance with the amount of intake air depending on the operating state, and An ignition plug is arranged at a position facing the combustion chamber that is biased from an intermediate position between the two intake ports to one intake port side, and during the engine intake stroke, the intake air drawn into the combustion chamber from each intake port causes the piston In a stratified combustion internal combustion engine configured to produce a tumble flow flowing in the reciprocating direction of the spark plug, the local equivalence ratio supplied through one intake port near the spark plug is set based on smoke emissions. 1. A fuel supply device for a stratified combustion internal combustion engine, characterized in that a control means is provided for controlling an amount of fuel supplied to the one intake port by the fuel supply means so that the amount of fuel supplied to the one intake port is equal to or less than the amount of fuel supplied to the one intake port by the fuel supply means. (5) Provided with two intake ports opening into the combustion chamber of the cylinder, and provided with a fuel supply means capable of supplying fuel to both of these two intake ports according to the amount of intake air depending on the operating state,
In addition, an ignition plug is disposed at a position facing the combustion chamber that is offset from an intermediate position between these two intake ports toward one intake port, so that the spark plug is sucked into the combustion chamber from each of the intake ports during the engine intake stroke. In a stratified combustion internal combustion engine configured to cause intake air to produce a tumble flow in the direction of reciprocating piston movement, the local equivalence ratio supplied through one intake port near the spark plug is based on the smoke emission amount. A control means is provided for controlling the amount of fuel supplied to the one intake port by the fuel supply means so that the amount of fuel is less than or equal to a set limit value, and a local equivalence ratio supplied through the one intake port is provided. If it becomes necessary to supply the combustion chamber with an amount of fuel that exceeds a limit value set based on smoke emissions, an auxiliary control means is provided to replenish the required amount of fuel through the other intake port. A fuel supply device for a stratified combustion internal combustion engine, characterized in that: (6) Provided with at least two intake ports opening into the combustion chamber of the cylinder, and provided with fuel supply means capable of supplying fuel to both of these two intake ports in accordance with the amount of intake air depending on the operating state, and An ignition plug is arranged at a position facing the combustion chamber that is biased from an intermediate position between the two intake ports to one intake port side, and during the engine intake stroke, the intake air drawn into the combustion chamber from each intake port causes the piston In a stratified combustion internal combustion engine configured to produce a tumble flow flowing in the reciprocating direction of the spark plug, the local equivalence ratio supplied through one intake port near the spark plug is set based on smoke emissions. 1. A fuel supply system for a stratified combustion internal combustion engine, characterized in that a control means is provided for controlling the ratio of the amount of fuel supplied to the two intake ports by the fuel supply means so that the ratio of the amount of fuel supplied to the two intake ports is equal to or less than a value equal to or less than the amount of fuel supplied to the two intake ports by the fuel supply means. (7) If the local equivalence ratio supplied through one of the intake ports is less than the limit value set based on the smoke emission amount, an increase or decrease in the amount of fuel supplied through the two intake ports is allowed. Then, the ratio of the amounts of fuel supplied to the two intake ports should be controlled, and the amount of fuel should be supplied to the combustion chamber such that the local equivalence ratio supplied through the one intake port exceeds the above-mentioned limit value. If the need arises, supply through said one intake port while supplying to said one intake port an amount of fuel such that the local equivalence ratio supplied through said one intake port does not exceed the above-mentioned limit value. In order to increase the ratio of the amount of fuel supplied through the other intake port to the amount of fuel supplied through the other intake port,
7. The fuel supply system for a stratified combustion internal combustion engine according to claim 6, wherein the ratio of fuel amounts supplied to the two intake ports is controlled.