JPH03189327A - Intake air quantity controller for engine - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a fuel injection device for an engine, and more specifically, to a fuel injection device for an engine that sufficiently removes harmful components from exhaust gas in a low-load operating region. The present invention relates to a fuel injection device for an engine that is capable of improving fuel efficiency in a medium load operating range, and that is also capable of obtaining high output in a high load operating range.

Prior Art An intake air amount control device for an engine includes an intake air restricting means such as a throttle valve, and is configured to control the amount of intake air to linearly increase in response to an increase in engine load. Volume control devices are known.

Problems to be Solved by the Invention However, when simply controlling the intake air amount so that it increases linearly in response to an increase in engine load, in the low-load operating region, the exhaust gas temperature However, the exhaust gas purification catalyst may not be heated to a temperature higher than its activation temperature, and harmful components in the exhaust gas may not be sufficiently removed. There were cases in which efficiency could not be sufficiently increased and fuel efficiency could not be sufficiently improved.

OBJECTS OF THE INVENTION The present invention provides an intake air amount control device for an engine equipped with an intake throttle means, which is capable of sufficiently removing harmful components in exhaust gas in a low-load operating range, and is capable of sufficiently removing harmful components in exhaust gas in a medium-load operating range. The object of the present invention is to provide an engine intake air amount control device that can sufficiently improve fuel efficiency.

SUMMARY OF THE INVENTION An object of the present invention is to reduce the amount of intake air in a low load operating range so that the mixture concentration near the ignition means reaches a high concentration close to the rich limit where ignition is possible, and to In the operating region, by providing a control means for controlling the intake air throttling means to increase the amount of intake air so that the concentration of the mixture near the ignition means is as low as near the lean limit where ignition is possible. achieved.

Effects of the Invention According to the present invention, in a low-load operating region, the amount of intake air is reduced so that the mixture concentration near the ignition means becomes high enough to be close to the rich limit that allows ignition. raising the temperature of the exhaust gas, thereby heating the exhaust gas purifying catalyst above its activation temperature;
Therefore, it is possible to sufficiently remove harmful components in the exhaust gas, and in the medium-load operating range, the amount of intake air can be reduced to a level where the mixture concentration near the ignition means is close to the lean limit where ignition is possible. Since the fuel consumption is increased so that the combustion efficiency is improved, it becomes possible to sufficiently improve fuel efficiency.

EXAMPLES Hereinafter, examples of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is a schematic vertical sectional view of a combustion injection device for an engine according to an embodiment of the present invention.

In FIG. 1, a rotor 4 rotatable around an eccentric shaft 3 is provided in a rotor housing 2 having a trochoid inner wall surface l, and three rotors are provided between the rotor housing 2 and the trochoid inner wall surface l. A working chamber 5.5.5 is formed.

An intake port 6 is open in the rotor housing 2, an intake passage 7 is connected to the intake port 6, a throttle valve 8 is provided in the intake passage 7, and an air cleaner is provided on the upstream side of the intake passage 7. 9 is provided.

Further, a trailing-side fuel injection nozzle 10 for injecting fuel in a horizontal direction is provided in the working chamber 5, and a trailing-side fuel injection nozzle 10 is provided so as to face the nozzle tip of the trailing-side fuel injection nozzle IO. A trailing side spark plug If is provided to ignite the fuel injected from the nozzle IO.

Further, on the leading side of the trailing side fuel injection nozzle 10 and the trailing side spark plug 11, a leading side fuel injection nozzle 12 that injects fuel in a nearly horizontal direction is provided in the working chamber 5. A leading-side spark plug 13 is provided opposite the tip of the injection nozzle 12 to ignite the fuel injected from the leading-side fuel injection nozzle I2.

A first fuel injection pump 14 and a second fuel injection pump 15 are connected to the trailing side fuel injection nozzle IO and the leading side fuel injection nozzle 12, respectively, and further, a trailing side spark plug II and a leading side spark plug I3 are connected. are electrically connected to the first igniter coil 16 and the second igniter coil 17, respectively.

Further, an exhaust boat 20 is opened in the rotor housing 2, and an exhaust gas purification device 2 is provided in the exhaust boat 20.
1 is connected to the exhaust passage 22.

The first fuel injection pump 14 also receives a load detection signal from an engine load detection means (not shown), an engine rotation speed detection signal from an engine rotation speed detection means, a misfire detection signal from a misfire detection means such as a G sensor, etc. and the second
A control unit 30 is provided which outputs a fuel injection signal to the fuel injection pump 15, an ignition signal to the first igniter coil 16 and the second igniter coil 17, and a throttle valve opening control signal to the throttle valve opening control means 23. It is being

FIG. 2 is a graph showing the relationship between the amount of fuel injected from the trailing side fuel injection nozzle lO and the leading side fuel injection nozzle 12 and the engine load. The amount of fuel injected per unit time from lO and the leading side fuel injection nozzle 12 is controlled to be constant, respectively, and FIG. Nozzle 1
2 shows the relationship between the injection time of fuel injected from No. 2 and the engine load. In Fig. 2, the shaded area is
The areas in which the injection time of the fuel injected from the leading-side fuel injection nozzle 12 is shown in matte finish indicate the injection time of the fuel injected from the trailing-side fuel injection nozzle 10, respectively.

As shown in FIG. 2, in the low-load operating range, fuel is mostly injected into the working chamber 5 from the leading-side fuel injection nozzle 12, and as the engine load increases, the leading-side fuel injection nozzle 12 The injection time of the fuel injected from the leading side fuel injection nozzle 12 gradually increases, and when the medium load operation region is reached, the injection time of the fuel injected from the leading side fuel injection nozzle 12 becomes constant, while the trailing side fuel injection nozzle lO Fuel will be injected from. The injection time of the fuel injected from the trailing side fuel injection nozzle 10 is also controlled to increase as the engine load increases.

FIG. 3 is a graph showing the relationship between the intake air amount Q and the engine load, and the line X indicates the intake air amount Q at which the mixture concentration near the leading side spark plug 13 reaches the rich limit. Y indicates the intake air amount Q at which the mixture concentration near the trailing side spark plug 11 and the leading side spark plug 13 reaches the lean limit, and
A line Z indicates the intake air amount Q when the throttle valve 8 is fully open. As shown in FIG. 3, the intake air amount Q is controlled according to the low-load operation region α, medium-load operation region β, and high-load operation region γ shown in FIG.

In this example, the rich limit and lean limit are
Based on a misfire detection signal from a misfire detection means such as a G sensor, the warm-up state of the engine, the trailing side fuel injection nozzle 10, and the leading side fuel injection nozzle 12 are determined respectively.
, the trailing side spark plug 11 and the leading side spark plug 13 can be changed by the control unit 30 according to changes over time.

As shown in FIG. 3, in the low-load operating region α, the control unit 30 outputs a throttle valve opening signal to the throttle valve opening control means 23, and the intake air amount Q is indicated by the line X. The opening degree of the throttle valve 8 is controlled so that the mixture concentration near the leading side spark plug 13 reaches the rich limit, and a combustion injection signal is sent to the second combustion injection pump 15 and a combustion injection signal is sent to the second igniter coil 17. An ignition signal is output, and fuel is injected into the working chamber 5 only from the leading-side fuel injection nozzle 12 according to the engine load, as shown in FIG. 2, and ignited by the leading-side spark plug 11. Therefore, combustion with a high degree of stratification can be realized, and the mixture concentration can be increased to the limit where ignition is possible, so the exhaust gas temperature can be made sufficiently high, and the exhaust gas can cause the exhaust gas provided in the exhaust passage 22 to The exhaust gas purifying catalyst in the gas purifying device 21 is heated to a temperature higher than its activation temperature, making it possible to sufficiently remove harmful components from the exhaust gas.

Further, in the medium load operating region β, the control unit 30 outputs a throttle valve opening signal to the throttle valve opening control means 23, so that the intake air amount Q is
The opening degree of the throttle valve 8 is controlled so that the mixture concentration near the trailing side ignition plug 1I and the leading side ignition plug 13 is at the lean limit, and the first combustion injection pump 14 and the second combustion A combustion injection signal is outputted to the injection pump 15, and an ignition signal is outputted to the first igniter coil 16 and the second igniter coil 17, respectively, as shown in FIG.
Depending on the engine load, fuel is delivered to the trailing side combustion injection nozzle 10 and the leading side combustion injection nozzle 12.
The fuel is injected into the working chamber 5 from the trailing side spark plug 1.
1 and the leading side spark plug 13. Therefore, the concentration of the air-fuel mixture is reduced to the limit where it can be ignited, thereby improving combustion efficiency and significantly improving fuel efficiency.

Furthermore, in the high load operating region γ, the control unit 30 causes the throttle valve opening control means 23 to
A throttle valve opening control signal is output to control the throttle valve 8 to be fully open, and a combustion injection signal is output to the first combustion injection pump 14 and the second combustion injection pump 15, respectively, and the first igniter coil is output. 16
and the second igniter coil 17 respectively, and as shown in FIG. 5 and ignited by the trailing side spark plug 11 and the leading side spark plug 13. therefore,
It becomes possible to obtain the desired output in a high-load operation region where high output is required.

According to this embodiment, in the low-load operating region α, the intake air amount is controlled so that the air-fuel mixture reaches the rich limit concentration at which it can be ignited. Therefore, the exhaust gas purification device 21 can sufficiently remove harmful components from the exhaust gas, and in the medium load operation region β. , so that the air-fuel mixture reaches the lean limit concentration that can be ignited.
Since the amount of intake air is controlled, combustion can be achieved with a sufficient amount of intake air, and combustion efficiency is greatly improved, making it possible to significantly improve fuel efficiency. Furthermore, in the high-load operating region γ where high output is required, the throttle valve 8 is controlled to be fully open and sufficient fuel is supplied into the working chamber, making it possible to obtain the desired high output. It becomes possible.

The present invention is not limited to the above embodiments (various changes are possible within the scope of the invention described in the claims, and these are also included within the scope of the present invention). Needless to say.

For example, in the embodiment, the trailing side fuel injection nozzle IO and the trailing side spark plug 11
A leading-side fuel injection nozzle 12 and a leading-side spark plug I3 are provided to provide a low-load operation range α.
In the above, combustion is injected only from the leading side combustion injection nozzle 12, and in medium to high load operating ranges, combustion is injected from the leading side combustion injection nozzle 12 and the trailing side combustion injection nozzle 10. Of course, the present invention can be applied to a direct fuel injection type rotary piston engine having only one fuel injection nozzle and one spark plug, and is not necessarily limited to a fuel direct injection type.

Furthermore, the present invention can also be applied to reciprocating engines rather than rotary piston engines.

Effects of the Invention According to the present invention, in an engine intake air amount control device equipped with an intake air throttle means, in a low load operating region,
It is possible to provide an engine intake air amount control device that can sufficiently remove harmful components from exhaust gas and can sufficiently improve fuel efficiency in a medium-load operating range.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical sectional view of a combustion injection device for an engine according to an embodiment of the present invention. FIG. 2 is a graph showing the relationship between the amount of fuel injected from the trailing side fuel injection nozzle and the leading side fuel injection nozzle and the engine load. FIG. 3 is a graph showing the relationship between intake air amount Q and engine load, and FIG. 4 is a graph showing the engine operating range in which intake air amount control is switched. l... Inner wall surface of rotor housing, 2... Rotor housing, 3... Eccentric shaft, 4... Rotor 5... Working chamber, 6... Intake port, 7... Intake passage, 8... Throttle valve, 9... Air cleaner, IO... Trailing side fuel injection nozzle, 11...
Trailing side spark plug, 12... Leading side fuel injection nozzle, 13... Leading side spark plug, 14... First fuel injection pump, 15... Second fuel injection pump, 16... Third 1 igniter coil, 17... second igniter coil, 20... exhaust port 21... exhaust gas purification device, 22... exhaust passage, 23... throttle valve opening control means, 30...
control unit. Figure 2 Engine load Figure 3 Engine load Figure 4 Engine speed

Claims (1)

[Claims] In an engine intake air amount control device equipped with an intake throttle means, in a low-load operating range, the intake air amount is reduced so that the mixture concentration near the ignition means reaches a high concentration close to the rich limit where ignition is possible. At the same time, in a medium load operating region, the intake air throttle means is controlled to increase the amount of intake air so that the mixture concentration near the ignition means becomes a low concentration near the lean limit where ignition is possible. An intake air amount control device for an engine, characterized in that it is provided with a control means.