JP2002235570A - Combustion device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accelerate combustion of fuel within a combustion chamber of an internal combustion engine over the entire of a fuel combustion process. SOLUTION: This device is provided with a high pressure gas injecting device 10 for injecting high pressure gas in the combustion chamber 7 of the internal combustion engine. Even before air/fuel mixture is ignited within the combustion chamber 7, high pressure gas is injected in the combustion chamber 7 by the high pressure injecting device 10 in the latter half of an engine compression stroke or in the first half of an engine expansion stroke.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a combustion device for an internal combustion engine.

[0002]

2. Description of the Related Art It is known that in a compression ignition type internal combustion engine, the amount of nitrogen oxides generated in a combustion chamber can be reduced by lowering the combustion temperature of fuel in the combustion chamber. As a method for achieving the above, there is a method of delaying the timing of injecting fuel into the combustion chamber. However, if the fuel injection timing is delayed, the fuel becomes difficult to burn, and black smoke is generated.

To solve such a problem, Japanese Patent Laid-Open No.
According to Japanese Patent No. 32014, high-pressure gas in a combustion chamber is accumulated in an accumulator in an engine compression stroke, and the high-pressure gas accumulated in the accumulator is injected into a combustion chamber in an engine expansion stroke, so that the high-pressure gas in the late stage of the combustion process of fuel is It promotes fuel combustion. That is, if high-pressure gas is injected into the combustion chamber at a later stage of the fuel combustion process, turbulence is formed in the gas in the combustion chamber, so that combustion of the fuel can be promoted.

[0004]

However, in the above publication, the combustion of fuel in the first half of the fuel combustion process is not promoted, and the effect of promoting fuel combustion according to the above publication is insufficient. Further, in order to achieve an object other than the purpose of reducing the amount of nitrogen oxides generated in the combustion chamber, it may be required to promote the combustion of fuel in the combustion chamber of the internal combustion engine. In light of these circumstances,
It is an object of the present invention to promote the combustion of fuel in the combustion chamber of an internal combustion engine throughout the fuel combustion process.

[0005]

According to a first aspect of the present invention, there is provided a combustion apparatus for an internal combustion engine having a high pressure gas injection device for injecting high pressure gas into a combustion chamber of the internal combustion engine. High-pressure gas is injected into the combustion chamber by the high-pressure gas injection device before the air-fuel mixture is ignited and in the latter half of the engine compression stroke or the first half of the engine expansion stroke. According to this, turbulence is formed in the air-fuel mixture before the air-fuel mixture in the combustion chamber is ignited.

According to a second aspect of the present invention, the high pressure gas in the combustion chamber is introduced into the high pressure gas injection device during the engine expansion stroke after the air-fuel mixture in the combustion chamber is ignited in the first aspect of the invention, and is held. The high-pressure gas is injected into the combustion chamber by the high-pressure gas injection device. In a third aspect, in the first aspect, whether or not high-pressure gas is injected by the high-pressure gas injection device is determined based on an engine speed and an engine load.

According to a fourth aspect of the present invention, when the engine load is reduced in the first aspect, the timing of injecting the high-pressure gas by the high-pressure gas injection device is delayed. In the fifth invention, 1
In the second invention, the high-pressure gas injection device further includes pressure detection means for detecting the pressure of the high-pressure gas held by the high-pressure gas injection device, and when the pressure detected by the pressure detection device decreases, the high-pressure gas injection device injects the high-pressure gas. Advance the timing to do it.

In a sixth aspect of the present invention, when the pressure detected by the pressure detecting means in the fifth aspect of the present invention decreases, the timing of igniting the air-fuel mixture in the combustion chamber is advanced. According to a seventh aspect, in the third aspect, a knock sensor for detecting knocking occurring in the combustion chamber is provided, and two learning values are calculated by two different learning processes executed using outputs of the knock sensor. When the high-pressure gas is injected by the high-pressure gas injector, the timing for igniting the air-fuel mixture in the combustion chamber is determined using one of the learning values, and when the high-pressure gas is not injected by the high-pressure gas injector, the other is used. Is used to determine the timing of igniting the air-fuel mixture in the combustion chamber.

According to an eighth aspect of the present invention, in the second aspect, the timing or the period for introducing high-pressure gas in the combustion chamber to the high-pressure gas injection device is calculated according to the operating state of the internal combustion engine. In a ninth aspect, in the eighth aspect, an engine speed and an engine load are used as the operating state of the internal combustion engine,
The timing or period for introducing high-pressure gas in the combustion chamber to the high-pressure gas injection device is calculated in accordance with the engine speed and the engine load, and the calculated timing or period is used to ignite the air-fuel mixture in the combustion chamber. The correction is made according to the timing of the operation.

[0010] In a tenth aspect based on the second aspect, there is provided a temperature detecting means for detecting the temperature of the internal combustion engine,
When the temperature detected by the temperature detecting means is lower than a predetermined temperature, the introduction of the high-pressure gas in the combustion chamber to the high-pressure gas injection device is prohibited and the injection of the high-pressure gas by the high-pressure gas injection device is prohibited. I do. According to an eleventh aspect, in the tenth aspect, there is provided a pressure detecting means for detecting a pressure of the high-pressure gas held by the high-pressure gas injector, and after the high-pressure gas is injected by the high-pressure gas injector, If the pressure detecting means detects a pressure higher than a predetermined pressure while prohibiting the introduction of high-pressure gas into the high-pressure gas injection device, it is determined that there is an abnormality in the high-pressure gas injection device.

In a twelfth aspect, in the second aspect, introduction of the high-pressure gas in the combustion chamber to the high-pressure gas injection device at the time of starting the internal combustion engine is prohibited and injection of the high-pressure gas by the high-pressure gas injection device is prohibited. According to a thirteenth aspect, in the twelfth aspect, there is provided a pressure detecting means for detecting the pressure of the high-pressure gas held by the high-pressure gas injection device, and the high-pressure gas in the high-pressure gas injection device is stopped when the operation of the internal combustion engine is stopped. When the pressure detecting means detects a pressure higher than a predetermined pressure while prohibiting the introduction of the high-pressure gas into the high-pressure gas injection device when the internal combustion engine is started, the high pressure is detected. It is determined that there is an abnormality in the gas injection device.

According to a fourteenth aspect, in the second aspect, there is provided a pressure detecting means for detecting the pressure of the high-pressure gas held by the high-pressure gas injector, and the high-pressure gas in the combustion chamber is introduced into the high-pressure gas injector. After that, if the pressure detecting means detects a pressure lower than a predetermined pressure before the high-pressure gas injection device injects the high-pressure gas, it is determined that the high-pressure gas injection device has an abnormality.

According to a fifteenth aspect, in the second aspect, a pressure detecting means for detecting a pressure of the high-pressure gas held by the high-pressure gas injection device is provided, and the high-pressure gas in the combustion chamber is introduced into the high-pressure gas injection device. If the pressure detecting means detects a pressure lower than a predetermined pressure during the operation, it is determined that the high-pressure gas injection device is abnormal. 16
According to a second aspect of the present invention, in the second aspect of the present invention, the high-pressure gas injection device further includes pressure detection means for detecting the pressure of the high-pressure gas held by the high-pressure gas injection device, and after the high-pressure gas injection device has injected the high-pressure gas, If the pressure detection means detects a pressure higher than a predetermined pressure before introducing the high-pressure gas into the high-pressure gas injection device, it is determined that the high-pressure gas injection device is abnormal. In any one of the thirteenth to sixteenth inventions, the internal combustion engine has a plurality of combustion chambers, and the high-pressure gas injection device has a high-pressure gas holding chamber for holding high-pressure gas in common with these combustion chambers, The pressure detecting means detects the pressure in the high-pressure gas holding chamber.

In the eighteenth invention, 11 or 13 to 1
In any one of the sixth inventions, the high-pressure gas injection device has a control valve that can be opened to inject high-pressure gas therefrom and to introduce high-pressure gas therein, and the high-pressure gas injection device has an abnormality. Is determined, the control valve is repeatedly opened and closed a plurality of times per engine cycle.

[0015]

Embodiments of the present invention will now be described with reference to the drawings. In FIG. 1, 1 is a cylinder head of an internal combustion engine, 2 is a cylinder block, 3 is an intake valve, 4 is an intake port, 5 is an exhaust valve, and 6 is an exhaust port. A combustion chamber 7 is formed by the cylinder head 1 and the cylinder block 2. A piston 8 is accommodated in the combustion chamber 7. Further, an ignition plug 9 projecting into the combustion chamber 7 is attached to the cylinder head 1.

Further, a high-pressure gas injection device 10 is attached to the cylinder head 1. The high-pressure gas injection device 10 has an electromagnetic valve 11 and a pressure accumulation chamber 12. The front end 13 of the solenoid valve 11 projects into the combustion chamber 7 and the rear end 14 thereof
2 is connected. The solenoid valve 11 is attached to the cylinder head 1 on the side where the intake valve 3 is arranged. According to this, since the time during which the electromagnetic valve 11 is exposed to the exhaust gas is shortened, it is possible to prevent the electromagnetic valve 11 from being thermally degraded due to the heat of the exhaust gas. When the solenoid valve 11 is opened, the pressure accumulating chamber 12 is opened.
Is communicated with the combustion chamber 7. Therefore, the solenoid valve 11
Functions as a control valve capable of controlling the state of communication between the pressure accumulating chamber 12 and the combustion chamber 7.

The pressure accumulating chamber 12 can hold a high-pressure gas at a pressure equal to or higher than the maximum pressure in the engine compression stroke. Therefore, the pressure accumulating chamber 12 functions as a high-pressure gas holding chamber.
The pressure accumulating chamber 12 is provided with a pressure sensor 15 as pressure detecting means for detecting the pressure of the gas held in the accumulating chamber 12. The pressure sensor 15 is connected to the electronic control device 16, and the output of the pressure sensor 15 is sent to the electronic control device 16. The electromagnetic valve 11 is also connected to the electronic control valve 16, and the opening and closing valve operation of the electromagnetic valve 11 is controlled by the electronic control device 16.

Further, a knock sensor 17 for detecting knocking generated in the combustion chamber 7 is attached to the cylinder block 2. Knock sensor 17 is connected to electronic control device 16, and the output of knock sensor 17 is sent to electronic control device 16. Furthermore, cylinder block 2
Has a cooling water passage 1 for flowing cooling water for cooling the internal combustion engine.
9 is formed. A temperature sensor 18 is disposed in the cooling water passage 19 as temperature detecting means for detecting the temperature of the cooling water. The temperature sensor 18 is connected to the electronic control device 16, and the output of the temperature sensor 18 is sent to the electronic control device 16. In this embodiment, the temperature of the internal combustion engine is estimated from the temperature of the cooling water detected by the temperature sensor 18.

In the internal combustion engine of the present embodiment, fuel is injected into intake air from a fuel injection valve (not shown) disposed in an engine intake passage connected to the intake port 4, and the fuel is mixed with air. Air (hereinafter simply referred to as an air-fuel mixture) is drawn into the combustion chamber 7 during the engine intake stroke. This air-fuel mixture is compressed in the engine compression stroke, and is ignited by the spark plug 9 near the top dead center of the engine compression. Then, the air-fuel mixture starts burning around the spark plug 9, and the combustion flame spreads to the surroundings.

Here, generally, the shorter the time from the start of combustion of the air-fuel mixture to the end of combustion, the higher the engine thermal efficiency. In order to shorten the combustion time of the air-fuel mixture in order to improve the engine heat efficiency, a turbulence is formed in the air-fuel mixture in the combustion chamber, and the turbulence may be maintained until the combustion of the air-fuel mixture is completed. Therefore, in this embodiment, as shown in FIG. 2, the solenoid valve 11 is opened during the engine expansion stroke after the mixture is ignited, and the high-pressure gas in the combustion chamber 7 is introduced into the pressure accumulation chamber 12 of the high-pressure gas injection device 10. (Time t1 in FIG. 2), and in the next engine cycle, the high-pressure gas is injected into the combustion chamber 7 by the high-pressure gas injection device 10 before the air-fuel mixture ignition and in the latter half of the engine compression stroke or the first half of the engine expansion stroke. Time t2 in FIG. 2). Thereby, turbulence is formed in the air-fuel mixture. In this embodiment, the time between the timing of injecting the high-pressure gas and the timing of igniting the air-fuel mixture is made as short as possible in order to maintain the turbulence thus formed as long as possible.

However, in order to form turbulence in the air-fuel mixture, and to maintain the turbulence, the timing of introducing the high-pressure gas, the timing of injecting the high-pressure gas, and the timing of igniting the air-fuel mixture are appropriately determined according to the operating state of the internal combustion engine. , Need to set. Also, depending on the operating state of the internal combustion engine, it is necessary to prohibit the introduction of the high-pressure gas into the high-pressure gas injection device 10 and the injection of the high-pressure gas into the combustion chamber 7 itself.

Based on these circumstances, the introduction of the high-pressure gas into the high-pressure gas injection device 10, the injection of the high-pressure gas into the combustion chamber 7, and the ignition of the air-fuel mixture in the present embodiment will be described in detail below. First, introduction of the high-pressure gas to the high-pressure gas injection device 10 in the present embodiment will be described. When introducing the high-pressure gas into the high-pressure gas injection device 10, the pressure in the combustion chamber 7 should be considered as the operating state of the internal combustion engine. That is, the high-pressure gas introduced and held in the high-pressure gas injection device 10 is injected into the combustion chamber 7 in the next engine cycle. Therefore, unless the pressure of the high-pressure gas held by the high-pressure gas injection device 10 is at least higher than the pressure in the combustion chamber 7 when the high-pressure gas is injected into the combustion chamber 7, the high-pressure gas will not enter the combustion chamber 7. Not injected.

In order to form strong turbulence in the air-fuel mixture, it is preferable that the pressure in the accumulator 12 be higher than the pressure in the combustion chamber 7 when the high-pressure gas is injected into the combustion chamber 7. Therefore, when the pressure in the combustion chamber 7 becomes the highest in the engine expansion stroke, the solenoid valve 11 of the high-pressure gas injection device 10 is opened, and the high-pressure gas in the combustion chamber 7 is introduced into the accumulator 12 and held. In the next engine cycle, high-pressure gas can be strongly injected from the high-pressure gas injection device 10.

Therefore, in this embodiment, the crank angle at which the pressure in the combustion chamber 7 (hereinafter, simply referred to as the in-cylinder pressure) becomes the maximum pressure during the combustion of the air-fuel mixture (hereinafter, the maximum pressure crank angle).
To open the solenoid valve 11 to hold the high-pressure gas in the accumulator 12. Specifically, in the present embodiment, as shown in FIG. 3, the maximum pressure crank angle is stored in the form of a map as a function of the engine speed Ne and the engine load L, and the engine speed Ne is stored using the map. The maximum pressure crank angle is calculated based on the engine load L, and the timing at which the solenoid valve 11 is opened to introduce the high pressure gas in the combustion chamber 7 into the accumulator chamber 12 (that is, the crank angle). And

According to the map shown in FIG. 3, in the engine operating region where the engine load L is smaller than the line A, the solenoid valve 11 is not opened during the combustion of the air-fuel mixture. It is forbidden. This is for the following reason. That is, if a turbulence is formed in the air-fuel mixture, the engine thermal efficiency increases at this point, but on the other hand, the high-pressure gas is taken out of the combustion chamber during combustion of the air-fuel mixture, so that the engine thermal efficiency decreases at this point. That is, unless the increase in the engine thermal efficiency due to the formation of the turbulence exceeds the decrease in the engine thermal efficiency due to the removal of the high-pressure gas, the overall engine thermal efficiency will decrease. Particularly, in a low load region, since the in-cylinder pressure is low, the removal of the high-pressure gas may lower the engine thermal efficiency. Further, in the low load region, the fuel in the air-fuel mixture is easily burned completely because the amount of fuel in the air-fuel mixture is small, and knocking is less likely to occur due to low in-cylinder pressure during fuel combustion. Under these circumstances, it is not necessary to form turbulence in the air-fuel mixture in the low load region. Therefore, in the engine operation region where the engine load L is smaller than the line A in the map of FIG.
The introduction of high-pressure gas into the air is prohibited.

According to the map of FIG. 3, in the engine operating region where the engine load L is larger than the line A and smaller than the line B, the crank angle is 15 ° after the top dead center of the engine compression.
(Hereinafter referred to as ATDC 15 °.) At a time, the solenoid valve 11 is opened, and high-pressure gas is introduced into the accumulator 12. That is, the maximum pressure crank angle is related to the engine speed Ne and the engine load L, and generally, the maximum pressure crank angle is the engine speed in the engine operation region where the engine load is medium and in the engine operation region where the engine load is small. ATDC regardless of number
It is around 15 °. Therefore, in the engine operating region where the engine load L is larger than the line A and smaller than the line B in the map of FIG.
The electromagnetic valve 11 is opened at the angle of °.

Further, according to the map shown in FIG. 3, in the engine operating region where the engine load L is larger than the line B, as the engine speed Ne decreases, the solenoid valve 11 is opened at a crank angle slower than ATDC 15 °, and As the engine load L decreases, the solenoid valve 11 opens at a crank angle slower than ATDC 15 °, and high-pressure gas is introduced into the accumulator 12.

That is, as will be described in detail later, the timing of igniting the air-fuel mixture is advanced as the engine speed is increased, and is delayed as the engine load is increased. In the engine operating region where the engine load is small, the maximum pressure crank angle is ATDC1.
It is around 5 °. In the engine operating region where the engine load is large, the mixture ignition timing tends to be delayed in order to avoid the occurrence of knocking in the combustion chamber.Therefore, the maximum pressure crank angle decreases as the engine speed decreases and as the engine load increases. Slows from 15 ° ATDC. That is, the introduction timing of the high-pressure gas is corrected according to the ignition timing of the air-fuel mixture.

For this reason, in the map of FIG. 3, in the engine operating region where the engine load L is larger than the line B, as the engine speed Ne decreases and the engine load L decreases, the electromagnetic force is reduced at a crank angle slower than ATDC 15 °. The valve 11 is opened. In the above-described embodiment, the opening timing of the solenoid valve is controlled so as to open the solenoid valve at the maximum pressure crank angle, but the timing at which the solenoid valve starts to open or the timing at which the solenoid valve closes is controlled. That is, the length of the opening period of the solenoid valve may be controlled to ensure that the solenoid valve is opened at the maximum pressure crank angle.

Next, the injection of the high-pressure gas into the combustion chamber 7 will be described. In the present embodiment, the base injection timing is calculated based on the engine speed and the engine load, and the base injection timing is corrected by an injection timing correction coefficient calculated based on the pressure in the accumulator, and finally the injection timing is calculated. obtain. When the high-pressure gas is injected from the electromagnetic valve 11 into the combustion chamber 7, as the pressure in the accumulator 12 becomes higher than the in-cylinder pressure, stronger turbulence is formed in the air-fuel mixture. Since the in-cylinder pressure becomes higher as it approaches the top dead center of the engine compression, the higher the pressure of the high-pressure gas injected at the earlier timing in the engine compression stroke and the later the high-pressure gas is injected at the later timing in the engine expansion stroke, The pressure difference between the pressure and the in-cylinder pressure is large, so that strong turbulence can be formed in the mixture.

However, when the high pressure gas is injected at an early timing in the engine compression stroke, the time period from when the high pressure gas is injected to when the mixture is ignited becomes longer, so that the turbulence in the mixture is attenuated during this time. Therefore, the turbulence in the air-fuel mixture after the ignition of the air-fuel mixture is small, and the effect of promoting the combustion of the air-fuel mixture due to the turbulence is reduced. In other words, in order to maintain the strongest possible turbulence even during combustion of the mixture, it is preferable that the injection timing of the high-pressure gas is closer to the ignition timing of the mixture.

In the engine expansion stroke before the mixture is ignited, the in-cylinder pressure decreases as the distance from the top dead center of the engine decreases. Therefore, the injection timing of the high-pressure gas is preferably closer to the ignition timing of the mixture. Therefore, in this embodiment, FIG.
The base injection timing for calculating the timing for injecting the high-pressure gas is stored in the form of a map as a function of the engine speed Ne and the engine load L as shown in FIG. The base injection timing for calculating the timing (i.e., the crank angle) for opening the solenoid valve 11 for injecting the high-pressure gas into the combustion chamber 7 is calculated based on the engine speed Ne and the engine load L.

According to the map of FIG. 4, in the engine operating region where the engine load L is smaller than the line C, the solenoid valve 11 is not opened before the mixture ignition and in the latter half of the engine compression stroke or the first half of the engine expansion stroke. Therefore, injection of the high-pressure gas into the combustion chamber 7 is prohibited. This is because, as described above, particularly in a low load region, it is not necessary to form turbulence in the air-fuel mixture, and the heat efficiency of the engine may be rather lowered.

According to the map of FIG. 4, in the engine operating region where the engine load L is larger than the line C, the base injection timing becomes earlier as the engine speed Ne becomes larger, and the base injection timing becomes earlier as the engine load L becomes larger. Become. This is for the following reason. That is, as the engine load increases, the amount of air (ie, the air-fuel mixture) sucked into the combustion chamber tends to increase, so that the in-cylinder pressure during the engine compression stroke increases. Therefore, the injection timing of the high-pressure gas needs to be advanced as the engine load increases. On the other hand, as the engine speed increases, the time required to advance by the unit crank angle decreases. Therefore, as the engine speed increases, even if the high-pressure gas injection timing is advanced, the turbulence until the mixture is ignited is less attenuated. For this reason, in the map of FIG. 4, in the engine operating region where the engine load L is larger than the line C, the base injection timing becomes earlier as the engine speed increases, and the base injection timing becomes earlier as the engine load increases.

The line C in FIG. 4 is located on the higher load side than the line A in FIG. Thereby, the high-pressure gas is supplied to the combustion chamber 7.
When high pressure gas is to be injected, the high pressure gas is always introduced into the accumulator 12 in the previous engine cycle. By the way, the pressure in the pressure accumulating chamber 12 at the time of high-pressure gas injection is not always constant, and differs for each immediately preceding engine cycle. Therefore, in order to form the most preferable turbulence in the air-fuel mixture, it is necessary to correct the base injection timing calculated from the map of FIG.

Therefore, in this embodiment, the injection timing correction coefficient Kinj is calculated based on the pressure Pc in the accumulator 12 according to the relationship shown in FIG. 5, and the injection base timing calculated from the map of FIG. to correct. In FIG. 5, when the pressure Pc in the accumulator 12 is higher than a predetermined pressure Pcth, the pressure P in the accumulator 12 is increased.
The injection timing correction coefficient Kinj takes a value that delays the base injection timing as c increases.

This is for the following reason. That is, as the pressure in the pressure accumulating chamber 12 is higher, a strong turbulence can be formed in the air-fuel mixture even when the in-cylinder pressure when the solenoid valve 11 is opened to inject the high-pressure gas is relatively high. Therefore, if the base injection timing calculated from the map of FIG. 4 is corrected to be delayed as the pressure in the accumulator 12 becomes higher, the time from the injection of the high-pressure gas to the ignition of the mixture becomes shorter, and the mixture is formed in the mixture. The turbulence attenuation is reduced, and the combustion of the air-fuel mixture is promoted.

On the other hand, the lower the pressure in the pressure accumulating chamber 12, the harder it is to form a strong turbulence in the air-fuel mixture. Accordingly, if the pressure in the accumulator 12 is corrected so as to advance the base injection timing calculated from the map of FIG. 4, it becomes easier to form a strong turbulence in the air-fuel mixture. For these reasons, FIG.
In the map, the injection timing correction coefficient Kinj takes a value that delays the base injection timing as the pressure Pc in the pressure accumulation chamber 12 increases.

According to the map of FIG. 5, when the pressure Pc in the pressure accumulating chamber 12 is lower than the predetermined pressure Pcth, the injection timing correction coefficient Kinj is not calculated and the command to prohibit the opening of the solenoid valve 11 is issued. Be emitted. This is for the following reason. That is, when the pressure in the pressure accumulating chamber 12 is low enough to inject the high-pressure gas into the combustion chamber 7, even if the solenoid valve 11 is opened to inject the high-pressure gas into the combustion chamber 7, on the contrary, The gas in the combustion chamber 7 flows into the accumulator 12, which lowers the in-cylinder pressure, which may hinder the combustion of the air-fuel mixture. Therefore, when the pressure in the accumulator 12 is relatively low, it is better not to open the solenoid valve 11 in order to inject high-pressure gas into the combustion chamber 7 from the viewpoint of promoting the combustion of the air-fuel mixture. For this reason, in the map of FIG. 5, when the pressure Pc in the pressure accumulation chamber 12 is lower than the predetermined pressure Pcth, the solenoid valve 11 is not opened.

When the injection timing of the high-pressure gas is calculated from the maps shown in FIGS. 4 and 5, when the injection timing is in the engine expansion stroke, the injection timing is corrected so as to be immediately before the ignition timing of the air-fuel mixture. According to this, since the in-cylinder pressure when the high-pressure gas is injected is further lower, stronger turbulence can be formed in the air-fuel mixture.

In this embodiment, if the mixture is turbulent in the engine operating region where the engine speed is large and the engine load is large, the engine heat efficiency is improved and the temperature of the exhaust gas is lowered. If the temperature of the exhaust gas is high, the components of the internal combustion engine may be thermally degraded due to the heat of the exhaust gas. To reduce the temperature of the exhaust gas to prevent this thermal degradation, for example, increase the fuel injection amount Then, there is a method of utilizing the heat of vaporization of the fuel, but this degrades the fuel efficiency. However, according to the present embodiment, since the temperature of the exhaust gas is lowered by promoting the combustion of the fuel, the fuel efficiency is not deteriorated.

Finally, the ignition of the air-fuel mixture will be described. In this embodiment, first, the base ignition timing is calculated based on whether or not the engine is being started and the engine temperature. Next, the base ignition timing is determined by a main correction coefficient obtained from the relationship between the engine speed and the engine load, a sub correction coefficient obtained from the injection timing of the high-pressure gas, and a learning correction coefficient (learning value obtained from the output of the knock sensor 17). ) To calculate the ignition timing. Hereinafter, the main correction coefficient, the sub correction coefficient, and the learning correction coefficient will be described in order.

In this embodiment, as shown in FIG. 6, the main correction coefficient is stored in the form of a map as a function of the engine speed Ne and the engine load L, and the main correction coefficient is calculated using the map. I do. When the base ignition timing is corrected using the main correction coefficient calculated from the map of FIG. 6, the base ignition timing is corrected so that the base ignition timing is advanced as the engine speed Ne increases, and the base ignition timing is delayed as the engine load L increases. Is corrected as follows.

The reason why the main correction coefficient is set as shown in the map of FIG. 6 according to the engine speed and the engine load is as follows. That is, as the engine speed increases, the time required to advance by the unit crank angle decreases, so that unless the air-fuel mixture is ignited at an early timing, the combustion of the air-fuel mixture will not end within the engine expansion stroke. Therefore, the ignition timing of the air-fuel mixture should be advanced as the engine speed increases. Further, since the combustion speed of the air-fuel mixture increases as the engine load increases, even if the air-fuel mixture is ignited at a later timing, the combustion of the air-fuel mixture ends within the engine expansion stroke. For these reasons, the main correction coefficients are as shown in the map shown in FIG.

Next, the sub correction coefficient will be described. As described above, if the time between the injection of the high-pressure gas and the ignition of the air-fuel mixture is long, the turbulence formed in the air-fuel mixture is attenuated, and the effect of promoting the combustion of the air-fuel mixture due to the turbulence is reduced. Therefore, the earlier the injection timing, the earlier the ignition timing should be. In consideration of this, in the present embodiment, as shown in FIG. 7, the sub correction coefficient is stored in the form of a map as a function of the injection timing, and the sub correction coefficient is calculated using the map. When the base ignition timing is corrected using the sub-correction coefficient calculated from the map of FIG. 7, the base ignition timing is corrected so that the earlier the injection timing, the earlier the base ignition timing.

Next, the learning correction coefficient will be described. Generally, it is better to advance the ignition timing in order to increase the engine thermal efficiency as much as possible. However, if the ignition timing is advanced, knocking occurs in the combustion chamber.
That is, it is preferable to actually advance the ignition timing within a range where knocking does not actually occur. Therefore, in this embodiment, the learning correction coefficient is calculated according to the flowchart shown in FIG. 8, and the base ignition timing is corrected based on this. According to the flowchart of FIG. 8, it is determined whether or not knocking is detected by the knock sensor 17 in step 100. When it is determined in step 100 that knocking has been detected, the routine proceeds to step 101, where the learning correction coefficient is corrected by a constant value so that the ignition timing is delayed. On the other hand, when it is determined in step 100 that knocking has not been detected, the routine proceeds to step 102, where the learning correction coefficient is corrected by a certain value so that the ignition timing is advanced.

By the way, the combustion rate of the air-fuel mixture is greatly different between the case where high-pressure gas is injected and the case where no high-pressure gas is injected. Therefore, in this embodiment, an engine operation region where high-pressure gas is injected (hereinafter, referred to as a high-pressure gas injection region) and an engine operation region where high-pressure gas is not injected (hereinafter, referred to as a non-high-pressure gas injection region). FIG. 8 is executed separately from the above, whereby two different learning correction coefficients are calculated from two different learning processes, and the ignition timing in the high pressure gas injection region is calculated in the high pressure gas injection region. The learning correction coefficient is used to calculate the ignition timing in the non-high-pressure gas injection region using the learning correction coefficient calculated in the non-high-pressure gas injection region. According to this, it is possible to reliably prevent knocking from occurring in the combustion chamber.

In the above embodiment, when the temperature of the internal combustion engine is low, the combustion itself of the air-fuel mixture is not stable, so that the air-fuel ratio of the air-fuel mixture is made richer than the stoichiometric air-fuel ratio. Further, even when the temperature of the internal combustion engine is high, even when the internal combustion engine is started, the combustion itself of the air-fuel mixture is not stable, so that the air-fuel ratio of the air-fuel mixture is made richer than the stoichiometric air-fuel ratio. For this reason, when the engine temperature is low or when the engine is started, the fuel in the air-fuel mixture is not easily vaporized, and soot is easily generated. At this time, if the solenoid valve 11 is opened, fuel or soot that has not been vaporized may clog the solenoid valve 11 and cause the solenoid valve 11 to break down.

Therefore, in the present embodiment, the opening of the solenoid valve 11 is prohibited when the engine is at low temperature and when the engine is started, that is, the introduction of high-pressure gas into the accumulator 12 is prohibited, and the high-pressure gas is also released from the combustion chamber. Injecting into 7 is prohibited. Also, during an engine transient operation in which the engine load gradually increases, even if the pressure in the accumulator chamber 12 is relatively high, the pressure in the accumulator chamber 12 is higher than the in-cylinder pressure when the high-pressure gas is injected into the combustion chamber 7. May also be low. Therefore, in the present embodiment, the injection of the high-pressure gas into the combustion chamber 7 is prohibited during the engine transient operation in which the engine load becomes larger than a predetermined increase rate.

The present invention is also applicable to an internal combustion engine in which fuel is directly injected into a combustion chamber. In the case of this type of internal combustion engine, when the fuel is present only in the vicinity of the spark plug so that the engine can be operated with a very large air-fuel ratio, the high pressure is used so that the fuel does not leave the vicinity of the spark plug. It is preferable to inject the gas into the combustion chamber from the viewpoint of promoting the combustion of the fuel.

The present invention can be applied to an internal combustion engine in which exhaust gas is circulated in a combustion chamber. In this case, it is preferable from the viewpoint of promoting combustion that high-pressure gas be injected into the combustion chamber in engine operation in which a large amount of exhaust gas is circulated. By the way, since the solenoid valve 11 of this embodiment injects high-pressure gas directly into the combustion chamber 7, its tip 13 is exposed to the gas in the combustion chamber 7. Therefore, the solenoid valve 1
There is a possibility that a valve opening failure in which the valve 1 remains closed without opening the valve or a valve opening failure in which the valve 1 remains open without closing the valve.

Therefore, in the present embodiment, the presence or absence of a failure (abnormality) of the solenoid valve 11 is diagnosed by using a plurality of methods described below in combination. Hereinafter, the failure diagnosis method according to the present embodiment will be described with reference to FIGS. 9 to 12. FIGS. 9 and 10 show a pressure storage chamber that is individually independent for each combustion chamber in an internal combustion engine having a plurality of combustion chambers. FIG. 11 is a diagram showing a pressure change in one accumulator chamber on a time axis in the case where
FIG. 12 is a diagram showing, on a time axis, a pressure change in one common accumulator when the internal combustion engine having a plurality of combustion chambers has one common accumulator for these combustion chambers. .

First, a first failure diagnosis method according to this embodiment will be described with reference to FIG. FIG. 9A shows the pressure change in the pressure accumulating chamber 12 when the solenoid valve 11 fails to open while the introduction and injection of the high-pressure gas are prohibited immediately after the injection of the high-pressure gas, that is, at the time ta indicated by the arrow. Is shown. If the solenoid valve 11 is normal when the introduction and injection of the high-pressure gas are prohibited immediately after the injection of the high-pressure gas, FIG.
, The pressure in the accumulator 12 should not change at all during the period from the engine compression stroke to the engine expansion stroke.

However, if the solenoid valve 11 fails to open during a time ta indicated by an arrow in FIG. 9A, that is, while the introduction and injection of the high-pressure gas is prohibited immediately after the injection of the high-pressure gas, the solenoid valve is opened during the period Pa. Since the valve 11 remains open, the gas in the combustion chamber 7 flows into the accumulator 12, and thus the pressure in the accumulator 12 greatly changes during the period Pa as shown by the solid line.

Therefore, in the first failure diagnosis method of this embodiment, the pressure in the accumulator 12 is determined in advance while the introduction and injection of the high-pressure gas are prohibited immediately after the injection of the high-pressure gas by utilizing this phenomenon. When the pressure becomes higher than the predetermined pressure, it is diagnosed that the solenoid valve 11 has a valve opening failure. Then, in an internal combustion engine having a plurality of combustion chambers and a plurality of solenoid valves respectively corresponding to the plurality of combustion chambers, but having a single accumulator, introducing high-pressure gas into all the accumulators immediately after injection of the high-pressure gas into any one of the combustion chambers. If one of the solenoid valves fails to open while the injection of the high-pressure gas into all the combustion chambers is prohibited, the period Pa, ie, the valve opening failure, also occurs as shown in FIG. During the period from the engine compression stroke to the engine expansion stroke in the combustion chamber corresponding to the solenoid valve, the pressure in the accumulator 12 changes as shown by the solid line.

Therefore, also in this case, the solenoid valve is opened when the pressure in the accumulator chamber 12 becomes higher than a predetermined pressure while the introduction and injection of the high-pressure gas are prohibited immediately after the injection of the high-pressure gas. It can be diagnosed that a failure has occurred. According to the first failure diagnosis, when the operation of the engine is stopped before the introduction of the high-pressure gas into the accumulator after the injection of the high-pressure gas, the introduction and injection of the high-pressure gas are prohibited when the engine is started. It is also possible to diagnose a solenoid valve opening failure that has occurred in between.

Next, a second failure diagnosis method according to the present embodiment will be described with reference to FIG. FIG. 9B shows the pressure change in the pressure accumulating chamber 12 at the time tb indicated by the arrow, that is, after the high-pressure gas injection and immediately before the introduction of the high-pressure gas, when the solenoid valve 11 fails to open. . Solenoid valve 1
1 is normal, after time tb in FIG.
The pressure in 2 should change as indicated by the dashed line.

However, if the solenoid valve 11 fails to open at time tb, the solenoid valve 11 remains open even during the period Pb in which the high-pressure gas should be held in the accumulator chamber 12, so that the pressure in the accumulator chamber 12 decreases during the period Pb. At Pb, it is much lower than the desired pressure. Therefore, in the second failure diagnosis method of the present embodiment, when the pressure in the accumulator 12 is lower than a predetermined pressure during a period from the introduction of the high-pressure gas to the time before the next injection of the high-pressure gas, the solenoid valve 11 fails to open. Diagnose that you are.

According to the second failure diagnosis, it is possible to diagnose a valve opening failure of the solenoid valve 11 from the introduction of the high-pressure gas to the next injection of the high-pressure gas. That is, as shown in FIG. 9C, for example, at time tc, that is, when the solenoid valve 11 fails to open immediately after introduction of the high-pressure gas, the pressure in the accumulator 12 decreases, and the pressure in the accumulator 12 decreases during the period Pc. There is ever. Therefore, according to the second failure diagnosis, a valve opening failure of the solenoid valve 11 from the introduction of the high-pressure gas to the next high-pressure gas injection can be diagnosed.

In an internal combustion engine having a plurality of combustion chambers and a plurality of solenoid valves corresponding to the respective combustion chambers but one pressure accumulating chamber, one of the solenoid valves introduces high-pressure gas immediately after injection from the solenoid valve. Before (for example, time t in FIG. 11B)
b), and when one of the solenoid valves is introduced after the introduction of the high-pressure gas through the solenoid valve and before the injection of the high-pressure gas through the next another solenoid valve (for example, at time t in FIG. 11C).
Similarly, when the valve opening failure occurs before c), the periods Pb, Pb,
Pc, that is, the pressure in the accumulator 12 from after the introduction of the high-pressure gas to before the next injection of the high-pressure gas is low as indicated by the solid line.

Therefore, also in this case, it can be diagnosed that the solenoid valve has failed to open when the pressure in the accumulator chamber 12 is low after the introduction of the high-pressure gas and before the next high-pressure gas injection, that is, during the periods Pb and Pc. it can. Next, a third failure diagnosis method according to the present embodiment will be described with reference to FIG. In the internal combustion engine of the present embodiment, when the operation of the engine is stopped, the solenoid valve 11 is always opened to discharge the high-pressure gas in the accumulator 12 to the outside, that is, into the combustion chamber 7. In this case, the operation of the internal combustion engine is resumed, the high-pressure gas is introduced into the accumulator 12, and when the electromagnetic valve 11 is opened and closed to inject the high-pressure gas into the combustion chamber 7, the electromagnetic valve 11 is normal. If there is, as shown by the chain line in FIG.
The pressure in 2 should change.

However, if the solenoid valve 11 has failed to close by the time ta indicated by the arrow in FIG. 10A, the pressure in the accumulator 12 changes as indicated by the solid line. That is, the pressure in the accumulator 12 remains low. Therefore, the third embodiment
In the first failure diagnosis method, when the high-pressure gas is introduced into the accumulator 12 after the engine is started and the high-pressure gas is to be injected into the combustion chamber 7, the pressure in the accumulator 12 is lower than a predetermined pressure. In this case, it is diagnosed that the solenoid valve 11 has a valve closing failure.

Next, a fourth failure diagnosis method according to the present embodiment will be described with reference to FIG. FIG. 10B shows the pressure change in the pressure accumulating chamber 12 at the time tb indicated by the arrow, that is, when the solenoid valve 11 fails to close immediately after the injection of the high-pressure gas and immediately before the introduction of the high-pressure gas. Solenoid valve 1
If 1 is normal, the pressure in the pressure accumulating chamber 12 changes as shown by a dashed line in a period Pb shown in FIG. 10B, that is, in a period from after the introduction of the high-pressure gas to before the next high-pressure gas injection.

However, if the solenoid valve 11 fails to close at time tb, the solenoid valve 11 does not open when the high-pressure gas is introduced immediately after that, so that the pressure in the pressure accumulating chamber 12 does not change at all during the period Pb as shown by the solid line. It remains unchanged and remains low. Therefore, in the fourth failure diagnosis method according to the present embodiment, when the pressure in the accumulator 12 is lower than a predetermined pressure during a period from the introduction of the high-pressure gas to before the injection of the high-pressure gas, the solenoid valve 11 fails to close. Diagnose that there is.

Then, in an internal combustion engine having a plurality of combustion chambers and a plurality of solenoid valves corresponding to the respective combustion chambers, but one of the pressure accumulating chambers, one of the solenoid valves 11 is supplied with the high pressure gas immediately after the high pressure gas injection. 12B, the period from the introduction of the high-pressure gas through one of the solenoid valves to the injection of the high-pressure gas through the next another electromagnetic valve, as shown in FIG. Accumulator chamber 12 during the period
The pressure within remains unchanged at all, as indicated by the solid line.

Therefore, also in this case, it can be diagnosed that the solenoid valve 11 has failed to close due to the low pressure in the accumulator 12 during the period from the introduction of the high-pressure gas to the injection of the high-pressure gas, ie, during the period Pb. . Next, a fifth failure diagnosis method according to the present embodiment will be described with reference to FIG. FIG. 10C shows the pressure change in the pressure accumulating chamber 12 at the time tc indicated by the arrow, that is, when the solenoid valve 11 fails to close immediately after the introduction of the high-pressure gas.

If the solenoid valve 11 is normal, the pressure in the accumulator 12 during the period Pc shown in FIG. 10C, that is, during the period from the injection of the high-pressure gas to the introduction of the next high-pressure gas, is indicated by a chain line. Change. However, if the solenoid valve 11 fails to close at time tc, the solenoid valve 1 will not be operated during the next high-pressure gas injection.
1 does not open, and the pressure in the accumulator
At c, it remains high without any change as shown by the solid line.

Therefore, in the fifth failure diagnosis method of the present embodiment, when the pressure in the accumulator 12 is higher than a predetermined pressure in a period from after injection of the high-pressure gas to before introduction of the next high-pressure gas, the solenoid valve 11 is activated. Diagnose a valve closing failure. Then, in an internal combustion engine having a plurality of combustion chambers and a plurality of solenoid valves corresponding to the respective combustion chambers, but having one accumulator chamber, one solenoid valve 11 is used before the high-pressure gas is injected from the solenoid valve 11 (for example, FIG. Similarly, when a valve closing failure occurs at time tc) in the period Pc) as shown in FIG.
c, that is, during the period from after the injection of the high-pressure gas to before the introduction of the next high-pressure gas, the pressure in the accumulator 12 remains high without any change as shown by the solid line.

Therefore, in this case as well, from the time after the injection of the high-pressure gas to the time immediately after the introduction of the high-pressure gas, that is, the period Pc
In this case, it can be diagnosed that the solenoid valve 11 has failed to close due to the high pressure in the accumulator chamber 12. FIG. 12A shows a state in which the introduction and injection of high-pressure gas are prohibited when the engine is started in an internal combustion engine having a plurality of combustion chambers and a plurality of solenoid valves respectively corresponding to the plurality of combustion chambers, but having a single accumulator chamber. The pressure change in the accumulator 12 when one of the solenoid valves fails to close is shown.

As shown in FIG. 12 (A), if the solenoid valve 11 is normal during the period Pa, that is, the period from the injection of the high-pressure gas to the introduction of the high-pressure gas immediately thereafter, the pressure in the accumulator 12 is indicated by a chain line. Should change to However, if one of the solenoid valves 11 fails to close while the introduction and injection of the high-pressure gas is prohibited at the time of engine start, the pressure in the accumulator 12 does not change at all during the period Pa as shown by the solid line. There is ever.

Therefore, also in this case, the period from the injection of the high-pressure gas to the introduction of the high-pressure gas immediately thereafter, that is, the period Pa
In this case, it can be diagnosed that the solenoid valve 11 has failed to close when the pressure in the pressure accumulating chamber 12 is higher than a predetermined pressure. In the above-described embodiment, when it is determined that the solenoid valve is malfunctioning, the electromagnetic valve may be turned on a plurality of times during one engine cycle, for example, between the engine intake stroke and the engine expansion stroke, preferably during the engine exhaust stroke. Repeat the opening and closing of the valve. According to this, when fuel or soot adheres to the solenoid valve, the fuel or soot is detached from the solenoid valve when the solenoid valve has failed, and the malfunction of the solenoid valve can be eliminated. Further, in the above-described embodiment, when it is diagnosed that the solenoid valve is out of order, display means for displaying this may be provided.

In the above-described embodiment, the solenoid valve is employed as a control valve for controlling the communication between the pressure accumulating chamber and the combustion chamber. It is also possible to employ a control valve that is opened in the latter half of the engine compression stroke or the first half of the engine expansion stroke and is opened during the engine expansion stroke after the mixture is ignited. Of course, in this case, a means is provided for interrupting the operation of the cam with the control valve so that the introduction and injection of the high-pressure gas can be prohibited.

[0073]

According to the present invention, since the air-fuel mixture in the combustion chamber is disturbed before being ignited, the air-fuel mixture is disturbed from the time the air-fuel mixture is ignited. Burning is promoted. That is, the combustion of fuel in the combustion chamber of the internal combustion engine is promoted throughout the fuel combustion process.

[Brief description of the drawings]

FIG. 1 is a diagram showing an internal combustion engine provided with a high-pressure gas injection device of the present invention.

FIG. 2 (A) is the pressure in the combustion chamber, (B) is the engine stroke, In is the intake stroke, Co is the compression stroke, Po is the expansion stroke, Ex is the exhaust stroke, and (C) is the pressure in the pressure accumulation chamber. Is shown.

FIG. 3 is a diagram showing a map used for calculating a high-pressure gas introduction timing.

FIG. 4 is a diagram showing a map used for calculating a base injection timing.

FIG. 5 is a diagram showing a map for calculating an injection timing correction coefficient.

FIG. 6 is a diagram showing a map for calculating a main correction coefficient.

FIG. 7 is a diagram showing a map for calculating a sub correction coefficient.

FIG. 8 is a diagram showing a flowchart for calculating a learning correction coefficient.

FIG. 9 is a diagram for explaining valve opening failure diagnosis.

FIG. 10 is a diagram for explaining valve closing failure diagnosis.

FIG. 11 is a diagram for explaining valve opening failure diagnosis.

FIG. 12 is a diagram for explaining valve closing failure diagnosis.

[Explanation of symbols]

 7: Combustion chamber 10: High-pressure gas injection device 11: Solenoid valve 12: Accumulation chamber 15: Pressure sensor 17: Knock sensor

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 43/00 301 F02D 43/00 301J 301B 45/00 340 45/00 340A 345 345Z 364 364Q 368 368D F02P 5 / 15 F02P 5/15 B F term (reference) 3G022 AA00 CA00 DA01 EA07 FA05 FA06 FA07 GA00 GA05 GA13 3G084 AA05 BA15 BA17 CA01 CA03 CA04 DA10 DA27 DA33 EA11 EB08 EB17 FA00 FA18 FA25 FA33 3G092 AA05 BB06 DF06 DE03S06 EA04 EA08 EA14 EC05 EC09 FA17 FB03 FB06 GA01 GA05 GA06 HA11Z HB03Z HC05Z HE01Z HE08Z 3G301 HA01 HA22 JA25 JB02 JB08 KA01 KA08 KA09 KA28 LA00 LB02 LB06 LC01 MA19 NA08 NC02 ND22 NE11 PE08 P08Z

Claims (18)

[Claims] 1. A combustion apparatus for an internal combustion engine having a high-pressure gas injection device for injecting high-pressure gas into a combustion chamber of the internal combustion engine, before the air-fuel mixture in the combustion chamber is ignited and the engine compression stroke A combustion device for an internal combustion engine in which high-pressure gas is injected into a combustion chamber by the high-pressure gas injection device in the second half or the first half of the engine expansion stroke. 2. The high-pressure gas in the combustion chamber is introduced into a high-pressure gas injection device during an engine expansion stroke after the air-fuel mixture in the combustion chamber is ignited, and the held high-pressure gas is introduced into the high-pressure gas injection device. The combustion device for an internal combustion engine according to claim 1, wherein the fuel is injected into the combustion chamber by the following. 3. The combustion device for an internal combustion engine according to claim 1, wherein whether or not high-pressure gas is injected by said high-pressure gas injection device is determined based on an engine speed and an engine load. 4. The combustion device for an internal combustion engine according to claim 1, wherein the timing of injecting the high pressure gas by the high pressure gas injection device is delayed when the engine load decreases. 5. A high-pressure gas injection device comprising a pressure detection means for detecting a pressure of the high-pressure gas held by the high-pressure gas injection device, and when the pressure detected by the pressure detection means decreases, the high-pressure gas injection device detects the high-pressure gas. 2. The combustion device for an internal combustion engine according to claim 1, wherein the injection timing is advanced. 6. The combustion device for an internal combustion engine according to claim 5, wherein the timing of igniting the air-fuel mixture in the combustion chamber is advanced when the pressure detected by the pressure detection means decreases. 7. A high-pressure gas injection device comprising: a knock sensor for detecting knocking occurring in a combustion chamber; two learning values calculated by two different learning processes executed using outputs of the knock sensor; When high pressure gas is being injected, the timing for igniting the air-fuel mixture in the combustion chamber is determined using one learning value, and when the high pressure gas is not injected by the high pressure gas injection device, the other learning value is used. 4. The combustion device for an internal combustion engine according to claim 3, wherein the timing for igniting the air-fuel mixture in the combustion chamber is determined. 8. The combustion device for an internal combustion engine according to claim 2, wherein a timing or a period for introducing the high-pressure gas in the combustion chamber to the high-pressure gas injection device is calculated according to an operation state of the internal combustion engine. 9. A timing or a period during which high-pressure gas in a combustion chamber is introduced into a high-pressure gas injection device according to the engine speed and the engine load, using the engine speed and the engine load as the operating state of the internal combustion engine. 9. The combustion device for an internal combustion engine according to claim 8, wherein the calculated timing or period is corrected according to the timing of igniting the air-fuel mixture in the combustion chamber. 10. A high pressure gas in a combustion chamber is supplied to a high pressure gas injection device when a temperature detected by the temperature detection device is lower than a predetermined temperature. 3. The combustion device for an internal combustion engine according to claim 2, wherein the introduction of the high-pressure gas is prohibited while the introduction of the high-pressure gas is prohibited by the high-pressure gas injection device. 11. A pressure detecting means for detecting a pressure of a high-pressure gas held by the high-pressure gas injection device,
If the pressure detecting means detects a pressure higher than a predetermined pressure while prohibiting the introduction of the high-pressure gas into the high-pressure gas injection device after the high-pressure gas injection device has injected the high-pressure gas, the high-pressure gas injection is performed. The combustion device for an internal combustion engine according to claim 10, wherein it is determined that the device has an abnormality. 12. The method according to claim 2, wherein when the internal combustion engine is started, introduction of the high-pressure gas in the combustion chamber to the high-pressure gas injection device is prohibited, and injection of the high-pressure gas by the high-pressure gas injection device is prohibited. Combustion device for internal combustion engines. 13. A pressure detecting means for detecting the pressure of the high-pressure gas held by the high-pressure gas injection device,
The high-pressure gas in the high-pressure gas injection device is released to the outside when the operation of the internal combustion engine is stopped, and the pressure detection means is provided while prohibiting the introduction of the high-pressure gas into the high-pressure gas injection device when the internal combustion engine is started. 13. The combustion device for an internal combustion engine according to claim 12, wherein when a pressure higher than a predetermined pressure is detected, it is determined that the high-pressure gas injection device is abnormal. 14. A pressure detecting means for detecting the pressure of the high-pressure gas held by the high-pressure gas injection device,
After the high-pressure gas in the combustion chamber is introduced into the high-pressure gas injection device and before the high-pressure gas injection device injects the high-pressure gas, when the pressure detecting means detects a pressure lower than a predetermined pressure, the high-pressure gas injection is performed. 3. The combustion device for an internal combustion engine according to claim 2, wherein it is determined that the device is abnormal. 15. A pressure detecting means for detecting the pressure of the high-pressure gas held by the high-pressure gas injection device,
3. The method according to claim 2, wherein when the pressure detecting means detects a pressure lower than a predetermined pressure while introducing the high-pressure gas in the combustion chamber into the high-pressure gas injection device, it is determined that the high-pressure gas injection device is abnormal. A combustion device for an internal combustion engine according to claim 1. 16. A pressure detecting means for detecting the pressure of the high-pressure gas held by the high-pressure gas injection device,
After the high-pressure gas is injected by the high-pressure gas injection device and before the high-pressure gas in the combustion chamber is introduced into the high-pressure gas injection device, when the pressure detecting means detects a pressure higher than a predetermined pressure, the high-pressure gas injection is performed. 3. The combustion device for an internal combustion engine according to claim 2, wherein it is determined that the device is abnormal. 17. The internal combustion engine has a plurality of combustion chambers, the high-pressure gas injection device has a common high-pressure gas holding chamber for holding high-pressure gas in these combustion chambers, and the pressure detecting means includes A pressure sensor for detecting a pressure in the high-pressure gas holding chamber,
Or a combustion device for an internal combustion engine according to any one of 13 to 16. 18. The high-pressure gas injection device has a control valve that can be opened to inject high-pressure gas therefrom and introduce high-pressure gas into the high-pressure gas injection device, and it is determined that the high-pressure gas injection device is abnormal. 2. The control valve according to claim 1, wherein the control valve is repeatedly opened and closed a plurality of times per one engine cycle.
17. The combustion device for an internal combustion engine according to any one of 1 to 13 to 16.